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Sample records for additional relevant studies

  1. Time-resolved XAFS spectroscopic studies of B-H and N-H oxidative addition to transition metal catalysts relevant to hydrogen storage

    SciTech Connect

    Bitterwolf, Thomas E.

    2014-12-09

    Successful catalytic dehydrogenation of aminoborane, H3NBH3, prompted questions as to the potential role of N-H oxidative addition in the mechanisms of these processes. N-H oxidative addition reactions are rare, and in all cases appear to involve initial dative bonding to the metal by the amine lone pairs followed by transfer of a proton to the basic metal. Aminoborane and its trimethylborane derivative block this mechanism and, in principle, should permit authentic N-H oxidative attrition to occur. Extensive experimental work failed to confirm this hypothesis. In all cases either B-H complexation or oxidative addition of solvent C-H bonds dominate the chemistry.

  2. The Personal Relevance of the Social Studies.

    ERIC Educational Resources Information Center

    VanSickle, Ronald L.

    1990-01-01

    Conceptualizes a personal-relevance framework derived from Ronald L. VanSickle's five areas of life integrated with four general motivating goals from Abraham Maslow's hierarchy of needs and Richard and Patricia Schmuck's social motivation theory. Illustrates ways to apply the personal relevance framework to make social studies more relevant to…

  3. Assessing the relevance of ecotoxicological studies for regulatory decision making.

    PubMed

    Rudén, Christina; Adams, Julie; Ågerstrand, Marlene; Brock, Theo Cm; Poulsen, Veronique; Schlekat, Christian E; Wheeler, James R; Henry, Tala R

    2016-09-07

    Regulatory policies in many parts of the world recognize either the utility of or the mandate that all available studies be considered in environmental or ecological hazard and risk assessment (ERA) of chemicals, including studies from the peer-reviewed literature. Consequently, a vast array of different studies and data types need to be considered. The first steps in the evaluation process involve determining whether the study is relevant to the ERA and sufficiently reliable. Relevance evaluation is typically performed using existing guidance but involves application of "expert judgment" by risk assessors. In the present paper, we review published guidance for relevance evaluation and, on the basis of the practical experience within the group of authors, we identify additional aspects and further develop already proposed aspects that should be considered when conducting a relevance assessment for ecotoxicological studies. From a regulatory point of view, the overarching key aspect of relevance concerns the ability to directly or indirectly use the study in ERA with the purpose of addressing specific protection goals and ultimately regulatory decision making. Because ERA schemes are based on the appropriate linking of exposure and effect estimates, important features of ecotoxicological studies relate to exposure relevance and biological relevance. Exposure relevance addresses the representativeness of the test substance, environmental exposure media, and exposure regime. Biological relevance deals with the environmental significance of the test organism and the endpoints selected, the ecological realism of the test conditions simulated in the study, as well as a mechanistic link of treatment-related effects for endpoints to the protection goal identified in the ERA. In addition, uncertainties associated with relevance should be considered in the assessment. A systematic and transparent assessment of relevance is needed for regulatory decision making. The relevance

  4. Responses of biological and chemical components in North East Atlantic coastal water to experimental nitrogen and phosphorus addition--a full scale ecosystem study and its relevance for management.

    PubMed

    Olsen, Yngvar; Reinertsen, Helge; Sommer, Ulrich; Vadstein, Olav

    2014-03-01

    The objective of this study was to quantify chemical and biological responses to an experimentally increased nutrient input to an open coastal planktonic ecosystem and to contribute to a scientific concept and credible indicators for managing nutrient supply to coastal waters. Data were derived in a 5 year fertilisation experiment of a tidal driven coastal lagoon at the outer coast off Central Norway (63°36' N, 9°33' E), with a surface area of 275.000 m(2), volume of 5.5 mill m(3), mean depth of 22 m and a water exchange rate of 0.19 day(-1). The lagoon was fertilised in the summer season 1998 and 1999, while summer seasons 1996-97 and 2000 and inflowing water were used as unfertilised references. Most measured chemical and biological variables showed linear responses with an increasing loading rate of inorganic N and P (LN and LP, respectively). PON, POP and POC (< 200 μm) responded significantly (P<0.05) as did chlorophyll a and phytoplankton C. DIN and DIP remained, however, constant and independent of LN and LP, respectively (P>0.05) as did heterotrophic biomass (P>0.05). We evaluate the response variables assuming a stepwise incorporation process of nutrients in the planktonic ecosystem and how that will interact with biological response times and water dilution rates. We suggest that PON is a credible indicator of both chemical and ecological states of the planktonic ecosystem and that natural background and upper critical concentrations are 46 and 88 mg PON m(-3), respectively. The study was supported by data from mesocosms. We discuss the scientific relevance of our suggestions, how results can be extrapolated to a broader geographical scale, and we propose a science-based concept for the management of nutrient emission to open coastal waters.

  5. Carryover negligibility and relevance in bioequivalence studies.

    PubMed

    Ocaña, Jordi; Sanchez O, Maria P; Carrasco, Josep L

    2015-01-01

    The carryover effect is a recurring issue in the pharmaceutical field. It may strongly influence the final outcome of an average bioequivalence study. Testing a null hypothesis of zero carryover is useless: not rejecting it does not guarantee the non-existence of carryover, and rejecting it is not informative of the true degree of carryover and its influence on the validity of the final outcome of the bioequivalence study. We propose a more consistent approach: even if some carryover is present, is it enough to seriously distort the study conclusions or is it negligible? This is the central aim of this paper, which focuses on average bioequivalence studies based on 2 × 2 crossover designs and on the main problem associated with carryover: type I error inflation. We propose an equivalence testing approach to these questions and suggest reasonable negligibility or relevance limits for carryover. Finally, we illustrate this approach on some real datasets.

  6. Additional Sawmill Electrical Energy Study.

    SciTech Connect

    Carroll, Hatch & Associates.

    1987-02-01

    This study was undertaken to investigate the potential for reducing use of electrical energy at lumber dry kilns by reducing fan speeds part way through the lumber drying process. It included three tasks: to quantify energy savings at a typical mill through field tests; to investigate the level of electric energy use at a representative sample of other mills and thereby to estimate the transferability of the conservation to the region; and to prepare a guidebook to present the technology to mill operators, and to allow them to estimate the economic value of adopting the technique at their facilities. This document reports on the first two tasks.

  7. Group theories: relevance to group safety studies.

    PubMed

    Benevento, A L

    1998-01-01

    Promoting safety in the workplace has been attempted in a variety of ways. Increasingly, industries are using groups such as safety teams and quality circles to promote worker safety. Group influences on individual behavior and attitudes have long been studied in the social psychology literature, but the theories have not been commonly found outside the psychology arena. This paper describes the group theories of group polarization, risky shift, social loafing, groupthink and team think and attempts to apply these theories to existing studies that examine work group influences on safety. Interesting parallels were found but only one study examined group influences as their primary focus of research. Since groups are increasingly used for safety promotion, future research on safety that studies group influences with respect to current group theories is recommended.

  8. ICRF antenna modifications and additions for TFTR: Relevance to BPX/ITER projections

    SciTech Connect

    Hosea, J.; Phillips, C.K.; Raftopoulos, S.; Stevens, J.; Wilson, J.R. . Plasma Physics Lab.); Bigelow, T.; Goulding, R.; Hoffman, D. )

    1991-01-01

    The TFTR Bay L and M antennas have been modified to improve their power handling capability. In particular, the Bay L antenna, which exhibited a lower than expected loading resistance, now has a configuration similar to that of Bay M -- slotted walls and septum -- and together with Bay M is expected to support 7 MW operations. The in situ loading enhancement achieved for the Modified Bay L design will serve to quantify models for the coupling effects of slots. Also, comparisons with Bay M loading performance will elucidate wave spectrum and antenna location (relative to in-vessel structures) effects. Two new antennas, with single/double row shields slanted at 6{degree} (along B) are to be added in the near future to augment the power capability to {approximately}12.5 MW. The relevance of the four antenna array features to quantifying BPX/ITER antenna characteristic projections for heating and current drive is discussed. 8 refs., 5 figs.

  9. An ERP Study on Self-Relevant Object Recognition

    ERIC Educational Resources Information Center

    Miyakoshi, Makoto; Nomura, Michio; Ohira, Hideki

    2007-01-01

    We performed an event-related potential study to investigate the self-relevance effect in object recognition. Three stimulus categories were prepared: SELF (participant's own objects), FAMILIAR (disposable and public objects, defined as objects with less-self-relevant familiarity), and UNFAMILIAR (others' objects). The participants' task was to…

  10. Effects of additives on surfactant phase behavior relevant to bacteriorhodopsin crystallization

    PubMed Central

    Berger, Bryan W.; Gendron, Colleen M.; Lenhoff, Abraham M.; Kaler, Eric W.

    2006-01-01

    The interactions leading to crystallization of the integral membrane protein bacteriorhodopsin solubilized in n-octyl-β-D-glucoside were investigated. Osmotic second virial coefficients (B22) were measured by self-interaction chromatography using a wide range of additives and precipitants, including polyethylene glycol (PEG) and heptane-1,2,3-triol (HT). In all cases, attractive protein–detergent complex (PDC) interactions were observed near the surfactant cloud point temperature, and there is a correlation between the surfactant cloud point temperatures and PDC B22 values. Light scattering, isothermal titration calorimetry, and tensiometry reveal that although the underlying reasons for the patterns of interaction may be different for various combinations of precipitants and additives, surfactant phase behavior plays an important role in promoting crystallization. In most cases, solution conditions that led to crystallization fell within a similar range of slightly negative B22 values, suggesting that weakly attractive interactions are important as they are for soluble proteins. However, the sensitivity of the cloud point temperatures and resultant coexistence curves varied significantly as a function of precipitant type, which suggests that different types of forces are involved in driving phase separation depending on the precipitant used. PMID:17088325

  11. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  12. The Study of Aggressive Pornography: The Vicissitudes of Relevance.

    ERIC Educational Resources Information Center

    Brannigan, Augustine; Goldenberg, Sheldon

    1987-01-01

    Reviews experimental studies of behavioral consequences of exposure to violent or aggressive pornography and evaluates the validity and relevance as support for censoring pornography in the aftermath of the Meese Commission. Finds research deficient in several areas, such as design, theoretical models, and interpretation, thus offering no…

  13. Additional EIPC Study Analysis. Final Report

    SciTech Connect

    Hadley, Stanton W; Gotham, Douglas J.; Luciani, Ralph L.

    2014-12-01

    Between 2010 and 2012 the Eastern Interconnection Planning Collaborative (EIPC) conducted a major long-term resource and transmission study of the Eastern Interconnection (EI). With guidance from a Stakeholder Steering Committee (SSC) that included representatives from the Eastern Interconnection States Planning Council (EISPC) among others, the project was conducted in two phases. Phase 1 involved a long-term capacity expansion analysis that involved creation of eight major futures plus 72 sensitivities. Three scenarios were selected for more extensive transmission- focused evaluation in Phase 2. Five power flow analyses, nine production cost model runs (including six sensitivities), and three capital cost estimations were developed during this second phase. The results from Phase 1 and 2 provided a wealth of data that could be examined further to address energy-related questions. A list of 14 topics was developed for further analysis. This paper brings together the earlier interim reports of the first 13 topics plus one additional topic into a single final report.

  14. The relevance of analogue studies for understanding obsessions and compulsions.

    PubMed

    Abramowitz, Jonathan S; Fabricant, Laura E; Taylor, Steven; Deacon, Brett J; McKay, Dean; Storch, Eric A

    2014-04-01

    Analogue samples are often used to study obsessive-compulsive (OC) symptoms and related phenomena. This approach is based on the hypothesis that results derived from such samples are relevant to understanding OC symptoms in individuals with a diagnosis of obsessive-compulsive disorder (OCD). Two decades ago, Gibbs (1996) reviewed the available literature and found initial support for this hypothesis. Since then there have been many important advances addressing this issue. The purpose of the present review was to synthesize various lines of research examining the assumptions of using analogue samples to draw inferences about people with OCD. We reviewed research on the prevalence of OC symptoms in non-clinical populations, the dimensional (vs. categorical) nature of these symptoms, phenomenology, etiology, and studies on developmental and maintenance factors in clinical and analogue samples. We also considered the relevance of analogue samples in OCD treatment research. The available evidence suggests research with analogue samples is highly relevant for understanding OC symptoms. Guidelines for the appropriate use of analogue designs and samples are suggested.

  15. Ecologic studies of rodent reservoirs: their relevance for human health.

    PubMed Central

    Mills, J. N.; Childs, J. E.

    1998-01-01

    Within the past few years, the number of "new" human diseases associated with small-mammal reservoirs has increased dramatically, stimulating renewed interest in reservoir ecology research. A consistent, integrative approach to such research allows direct comparisons between studies, contributes to the efficient use of resources and data, and increases investigator safety. We outline steps directed toward understanding vertebrate host ecology as it relates to human disease and illustrate the relevance of each step by using examples from studies of hosts associated with rodent-borne hemorrhagic fever viruses. PMID:9866729

  16. A Study of Adaptive Relevance Feedback - UIUC TREC-2008 Relevance Feedback Experiments

    DTIC Science & Technology

    2008-11-01

    1− β)αf + βαd where if αd < αf , β = 1; otherwise β = 0. 5. EXPERIMENT RESULTS 5.1 Data Preprocessing We employ the Lemur toolkit (version 4.5) and... Lemur toolkit, we adopt the KL-Divergence retrieval model with mixture model feedback to do relevance feed- back experiments (related parameters are

  17. Experimental studies of reactions relevant for γ-process nucleosynthesis

    SciTech Connect

    Scholz, P.; Endres, J.; Hennig, A.; Mayer, J.; Netterdon, L.; Zilges, A.; Sauerwein, A.

    2014-05-09

    We report on our recent experimental studies of reactions relevant for the γ process nucleosynthesis. Applying the activation method using the Cologne Clover Counting Setup total cross sections of the reactions {sup 168}Yb(α,γ), {sup 168}Yb(α,n), and {sup 187}Re(α,n) could be obtained. Furthermore, the reaction {sup 89}Y(p,γ) was investigated via the in-beam technique with HPGe detectors at the high-efficiency g-ray spectrometer HORUS in Cologne in order to determine partial and total cross sections.

  18. It's All About You: an ERP study of emotion and self-relevance in discourse.

    PubMed

    Fields, Eric C; Kuperberg, Gina R

    2012-08-01

    Accurately communicating self-relevant and emotional information is a vital function of language, but we have little idea about how these factors impact normal discourse comprehension. In an event-related potential (ERP) study, we fully crossed self-relevance and emotion in a discourse context. Two-sentence social vignettes were presented either in the third or the second person (previous work has shown that this influences the perspective from which mental models are built). ERPs were time-locked to a critical word toward the end of the second sentence which was pleasant, neutral, or unpleasant (e.g., A man knocks on Sandra's/your hotel room door. She/You see(s) that he has agift/tray/gunin his hand.). We saw modulation of early components (P1, N1, and P2) by self-relevance, suggesting that a self-relevant context can lead to top-down attentional effects during early stages of visual processing. Unpleasant words evoked a larger late positivity than pleasant words, which evoked a larger positivity than neutral words, indicating that, regardless of self-relevance, emotional words are assessed as motivationally significant, triggering additional or deeper processing at post-lexical stages. Finally, self-relevance and emotion interacted on the late positivity: a larger late positivity was evoked by neutral words in self-relevant, but not in non-self-relevant, contexts. This may reflect prolonged attempts to disambiguate the emotional valence of ambiguous stimuli that are relevant to the self. More broadly, our findings suggest that the assessment of emotion and self-relevance are not independent, but rather that they interactively influence one another during word-by-word language comprehension.

  19. Dose Addition Models Based on Biologically Relevant Reductions in Fetal Testosterone Accurately Predict Postnatal Reproductive Tract Alterations by a Phthalate Mixture in Rats

    PubMed Central

    Howdeshell, Kembra L.; Rider, Cynthia V.; Wilson, Vickie S.; Furr, Johnathan R.; Lambright, Christy R.; Gray, L. Earl

    2015-01-01

    Challenges in cumulative risk assessment of anti-androgenic phthalate mixtures include a lack of data on all the individual phthalates and difficulty determining the biological relevance of reduction in fetal testosterone (T) on postnatal development. The objectives of the current study were 2-fold: (1) to test whether a mixture model of dose addition based on the fetal T production data of individual phthalates would predict the effects of a 5 phthalate mixture on androgen-sensitive postnatal male reproductive tract development, and (2) to determine the biological relevance of the reductions in fetal T to induce abnormal postnatal reproductive tract development using data from the mixture study. We administered a dose range of the mixture (60, 40, 20, 10, and 5% of the top dose used in the previous fetal T production study consisting of 300 mg/kg per chemical of benzyl butyl (BBP), di(n)butyl (DBP), diethyl hexyl phthalate (DEHP), di-isobutyl phthalate (DiBP), and 100 mg dipentyl (DPP) phthalate/kg; the individual phthalates were present in equipotent doses based on their ability to reduce fetal T production) via gavage to Sprague Dawley rat dams on GD8-postnatal day 3. We compared observed mixture responses to predictions of dose addition based on the previously published potencies of the individual phthalates to reduce fetal T production relative to a reference chemical and published postnatal data for the reference chemical (called DAref). In addition, we predicted DA (called DAall) and response addition (RA) based on logistic regression analysis of all 5 individual phthalates when complete data were available. DA ref and DA all accurately predicted the observed mixture effect for 11 of 14 endpoints. Furthermore, reproductive tract malformations were seen in 17–100% of F1 males when fetal T production was reduced by about 25–72%, respectively. PMID:26350170

  20. Structure Property Studies for Additively Manufactured Parts

    SciTech Connect

    Milenski, Helen M; Schmalzer, Andrew Michael; Kelly, Daniel

    2015-08-17

    Since the invention of modern Additive Manufacturing (AM) processes engineers and designers have worked hard to capitalize on the unique building capabilities that AM allows. By being able to customize the interior fill of parts it is now possible to design components with a controlled density and customized internal structure. The creation of new polymers and polymer composites allow for even greater control over the mechanical properties of AM parts. One of the key reasons to explore AM, is to bring about a new paradigm in part design, where materials can be strategically optimized in a way that conventional subtractive methods cannot achieve. The two processes investigated in my research were the Fused Deposition Modeling (FDM) process and the Direct Ink Write (DIW) process. The objectives of the research were to determine the impact of in-fill density and morphology on the mechanical properties of FDM parts, and to determine if DIW printed samples could be produced where the filament diameter was varied while the overall density remained constant.

  1. DNA binding studies of tartrazine food additive.

    PubMed

    Kashanian, Soheila; Zeidali, Sahar Heidary

    2011-07-01

    The interaction of native calf thymus DNA with tartrazine in 10 mM Tris-HCl aqueous solution at neutral pH 7.4 was investigated. Tartrazine is a nitrous derivative and may cause allergic reactions, with a potential of toxicological risk. Also, tartrazine induces oxidative stress and DNA damage. Its DNA binding properties were studied by UV-vis and circular dichroism spectra, competitive binding with Hoechst 33258, and viscosity measurements. Tartrazine molecules bind to DNA via groove mode as illustrated by hyperchromism in the UV absorption band of tartrazine, decrease in Hoechst-DNA solution fluorescence, unchanged viscosity of DNA, and conformational changes such as conversion from B-like to C-like in the circular dichroism spectra of DNA. The binding constants (K(b)) of DNA with tartrazine were calculated at different temperatures. Enthalpy and entropy changes were calculated to be +37 and +213 kJ mol(-1), respectively, according to the Van't Hoff equation, which indicated that the reaction is predominantly entropically driven. Also, tartrazine does not cleave plasmid DNA. Tartrazine interacts with calf thymus DNA via a groove interaction mode with an intrinsic binding constant of 3.75 × 10(4) M(-1).

  2. The relevance of phylogeny to studies of global change.

    PubMed

    Edwards, Erika J; Still, Christopher J; Donoghue, Michael J

    2007-05-01

    Phylogenetic thinking has infiltrated many areas of biological research, but has had little impact on studies of global ecology or climate change. Here, we illustrate how phylogenetic information can be relevant to understanding vegetation-atmosphere dynamics at ecosystem or global scales by re-analyzing a data set of carbonic anhydrase (CA) activity in leaves that was used to estimate terrestrial gross primary productivity. The original calculations relied on what appeared to be low CA activity exclusively in C4 grasses, but our analyses indicate that such activity might instead characterize the PACCAD grass lineage, which includes many widespread C3 species. We outline how phylogenetics can guide better taxon sampling of key physiological traits, and discuss how the emerging field of phyloinformatics presents a promising new framework for scaling from organism physiology to global processes.

  3. Performance of a mixed filter to identify relevant studies for mixed studies reviews

    PubMed Central

    El Sherif, Reem; Pluye, Pierre; Gore, Genevieve; Granikov, Vera; Hong, Quan Nha

    2016-01-01

    Objective Mixed studies reviews include empirical studies with diverse designs. Given that identifying relevant studies for such reviews is time consuming, a mixed filter was developed. Methods The filter was used for six journals from three disciplines. For each journal, database records were coded “empirical” (relevant) when they mentioned a research question or objective, data collection, analysis, and results. We measured precision (proportion of retrieved documents being relevant), sensitivity (proportion of relevant documents retrieved), and specificity (proportion of nonrelevant documents not retrieved). Results Records were coded with and without the filter, and descriptive statistics were performed, suggesting the mixed filter has high sensitivity. PMID:26807052

  4. TESTING FOR ADDITIVITY IN THE LOW DOSE REGION OF AN ENVIRONMENTALLY RELEVANT MIXTURE OF 18 OLYHALOGENATED AROMATIC HYDROCARBONS.

    EPA Science Inventory

    A common default assumption in risk assessment of chemical mixtures is that the chemicals combine additively in the low dose region. Under additivity, with information from single chemical dose-response data, the risk associated with the mixture can be estimated. The objective ...

  5. Pair Comparison Study of the Relevance of Nine Basic Science Courses

    ERIC Educational Resources Information Center

    Spilman, Edra L.; Spilman, Helen W.

    1975-01-01

    Reports a survey study in which basic science courses were rated according to relevance. Notes approaches for making the anatomy disciplines more relevant because results showed them of lowest relevancy compared with physiology, pathology, and pharmacology which were rated of highest relevance and with biochemistry and microbiology which fell…

  6. Discovering ecologically relevant knowledge from published studies through geosemantic searching

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It is easier to search the globe for research on genes of a local plant or animal than to find local field research on that plant’s ecology. While internet applications can find the closest coffee shop, it is difficult to find where the nearest relevant research was conducted. As a result, ecologi...

  7. Theoretical and experimental studies relevant to interpretation of auroral emissions

    NASA Technical Reports Server (NTRS)

    Keffer, Charles E.

    1994-01-01

    This report describes the accomplishments of a program designed to develop the tools necessary to interpret auroral emissions measured from a space-based platform. The research was divided into two major areas. The first area was a laboratory study designed to improve our understanding of the space vehicle external environment and how it will affect the space-based measurement of auroral emissions. Facilities have been setup and measurements taken to simulate the gas phase environment around a space vehicle; the radiation environment encountered by an orbiting vehicle that passes through the Earth's radiation belts; and the thermal environment of a vehicle in Earth orbit. The second major area of study was a modeling program to develop the capability of using auroral images at various wavelengths to infer the total energy influx and characteristic energy of the incident auroral particles. An ab initio auroral calculation has been added to the extant ionospheric/thermospheric global modeling capabilities within our group. Once the addition of the code was complete, the combined model was used to compare the relative intensities and behavior of various emission sources (dayglow, aurora, etc.). Attached papers included are: 'Laboratory Facility for Simulation of Vehicle-Environment Interactions'; 'Workshop on the Induced Environment of Space Station Freedom'; 'Radiation Damage Effects in Far Ultraviolet Filters and Substrates'; 'Radiation Damage Effects in Far Ultraviolet Filters, Thin Films, and Substrates'; 'Use of FUV Auroral Emissions as Diagnostic Indicators'; and 'Determination of Ionospheric Conductivities from FUV Auroral Emissions'.

  8. Theoretical and experimental studies relevant to interpretation of auroral emissions

    NASA Technical Reports Server (NTRS)

    Keffer, Charles E.

    1991-01-01

    The accomplishments achieved over the past year are detailed with emphasis on the interpretation or auroral emissions and studies of potential spacecraft-induced contamination effects. Accordingly, the research was divided into two tasks. The first task is designed to add to the understanding of space vehicle induced external contamination. An experimental facility for simulation of the external environment for a spacecraft in low earth orbit was developed. The facility was used to make laboratory measurements of important phenomena required for improving the understanding of the space vehicle induced external environment and its effect on measurement of auroral emissions from space-based platforms. A workshop was sponsored to provide a forum for presentation of the latest research by nationally recognized experts on space vehicle contamination and to discuss the impact of this research on future missions involving space-based platforms. The second task is to add an ab initio auroral calculation to the extant ionospheric/thermospheric global modeling capabilities. Once the addition of the code was complete, the combined model was to be used to compare the relative intensities and behavior of various emission sources (dayglow, aurora, etc.). Such studies are essential to an understanding of the types of vacuum ultraviolet (VUV) auroral images which are expected to be available within two years with the successful deployment of the Ultraviolet Imager (UVI) on the ISTP POLAR spacecraft. In anticipation of this, the second task includes support for meetings of the science working group for the UVI to discuss operational and data analysis needs. Taken together, the proposed tasks outline a course of study designed to make significant contributions to the field of space-based auroral imaging.

  9. Laboratory studies of heterogeneous processes relevant to Mars

    NASA Astrophysics Data System (ADS)

    Gough, Raina V.

    Heterogeneous (gas-surface) processes may play an important role in both the atmospheric and surface chemistry of Mars. Atmospheric species may be affected by the chemistry and physical properties of the planetary surface and the surface material may be affected by the components and properties of the atmosphere. In this thesis, several laboratory studies are described which experimentally investigate two types of atmosphere-surface systems likely to exist on Mars. First, experiments were performed to better understand the spatial and temporal variability of atmospheric methane (CH4) on Mars. Reported CH4 plumes in the atmosphere of Mars are difficult to explain using known chemical or physical processes. The observations imply a strong, present-day source and also a rapid yet unknown CH4 sink. We have investigated the potential role of mineral dust in CH4 variability. First, using a Knudsen cell capable of simulating Martian temperature and pressure conditions, we have studied the adsorption of CH4 to a Martian mineral analog as a function of temperature. An uptake coefficient was determined and then applied to the Martian surface-atmosphere system. Our results suggest that adsorption to soil grains could possibly affect the CH4 mixing ratio on a seasonal time scale especially at mid-latitude regions. Additionally, chemical oxidation of CH4 by oxidants thought to exist in the Martian regolith was studied. The Viking mission in the 1970's found Martian soil was able to oxidize complex organic compounds to CO 2. The identity of the oxidant is unknown, but has been proposed to be either hydrogen peroxide or perchlorate salts. We used a gas chromatograph to determine if simulated Mars soil containing these oxidants was able to oxidize CH4 to CO2. However, no CH4 was oxidized within the detection limit of the instrument and only an upper limit reaction coefficient could be reported. Even these upper limit values suggest CH 4 could not be removed from the Martian

  10. Relevant and Irrelevant Fear in Flooding - A Crossover Study of Phobic Patients - Republished Article.

    PubMed

    Watson, J P; Marks, I M

    2016-09-01

    This study investigated the role of relevant vs irrelevant fear cues in the flooding of phobic patients. Six specific phobics and 10 agoraphobics were treated in a balanced crossover design. Eight patients had eight sessions of imaginal flooding concerned with their phobias followed by eight imaginal sessions concerned with situations which are normally frightening to anybody. Another eight patients had the same two treatments in the reverse order. The combined effects of both treatments after 16 sessions resulted in significant improvement on clinical, attitudinal, and heart-rate measures. Improvement was maintained at six months follow-up. Eight sessions by each treatment alone also produced significant improvement on clinical and attitudinal measures. Irrelevant fear also produced significant improvement in heart-rate and skin-conductance measures. The two treatments did not differ significantly from each other in their effects, except that irrelevant fear produced significantly more improvement than did relevant flooding in subjective anxiety during phobic imagery. The two treatments had significantly different prognostic correlates. Heightened physiological activity at the start of treatment predicted a good outcome to relevant flooding but not to irrelevant fear. High subjective anxiety during imagery before treatment predicted poor outcome to irrelevant fear. High anxiety during treatment sessions predicted good outcome to irrelevant fear, but did not correlate with outcome to relevant flooding. The experience of relevant and irrelevant fear in fantasy reduced phobic anxiety and avoidance to a similar extent, but appeared to do so through different mechanisms. These mechanisms need not be mutually exclusive and might be additive.

  11. Self-relevant beauty evaluation: Evidence from an event-related potentials study.

    PubMed

    Kong, Fanchang; Zhang, Yan; Tian, Yuan; Fan, Cuiying; Zhou, Zongkui

    2015-03-01

    This study examines the electrophysiological correlates of beauty evaluation when participants performed the self-reference task. About 13 (7 men, 6 women) undergraduates participated in the experiment using event-related potentials. Results showed that the response to self-relevant information was faster compared to other-relevant information and no significant differences for self-relevant relative to mother-relevant information were observed. Both physical and interior beauty words for self-relevant information showed an enhanced late positive component as compared to other-relevant information. Physical beauty for self-relevant information yielded a larger late positive component in contrast to mother-relevant information but not for interior beauty. This study indicates that beauty is specific to the person who judges it though an individual and one's mother may hold similar views of interior beauty.

  12. Spectroscopic Studies of Molecular Systems relevant in Astrobiology

    NASA Astrophysics Data System (ADS)

    Fornaro, Teresa

    2016-01-01

    . The reliability of such theoretical results has been validated with respect to experiments, by performing infrared measurements of uracil in the solid state through the Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) technique. The good performance in predicting the experimental shifts of the vibrational frequencies of uracil due to the intermolecular hydrogen bonds in the solid state with respect to uracil isolated in Argon matrix, has allowed also to provide some new assignments of the experimental spectrum of uracil in the solid state. Finally, the study of molecule-mineral interactions has been addressed, investigating experimentally the thermodynamics of the adsorption process of nucleic acid components on brucite, a serpentinite-hosted hydrothermal mineral, through determination of the equilibrium adsorption isotherms. Additionally, surface complexation studies have been carried out to get the stoichiometry of surface reactions and the associated electrical work. Such surface complexation modeling has provided reasonable inferences for the possible surface complexes, determining the number of inner/outer-sphere linkages for the adsorbates and the number of surface sites involved in the reaction stoichiometry. However, to distinguish the specific functional groups which constitute the points of attachment to the surface, further quantum mechanical simulations on the energetics of these complexes and spectroscopic characterizations are in progress.

  13. Laboratory Studies of Ammonia Ices Relevant to the Jovian Atmosphere

    NASA Astrophysics Data System (ADS)

    Meharchand, R. T.; Boulter, J. E.; Baer, C. E.; Kalogerakis, K. S.

    2004-12-01

    Ammonia ice condensation and cloud formation microphysics are topics of relevance for understanding the atmospheres of the giant planets. Ammonia ices are also considered important components of the icy satellites found in the outer solar system, and are thought to play an important role in their geological activity. Although observational evidence and thermochemical models suggest ammonia clouds in the Jovian atmosphere should be ubiquitous, less than only 1% of Jupiter's atmosphere appears covered by spectrally identifiable ammonia clouds, with a clear preference in turbulent regions.1,2 The paradox of the rather scarce spectroscopic signatures of ammonia clouds and their appearance in turbulent regions suggests that the nascent ammonia clouds may undergo processing that modifies their spectroscopic properties. No relevant laboratory experimental results are available to resolve this problem. Two possible sources of processing that have been suggested in the literature include photochemical solid-state modification (''tanning'') and coating of ammonia particles by other substances present in the stratospheric haze.2,3 We are performing laboratory investigations with the objective to provide information on the photophysical and chemical processes that control the optical properties of the Jovian ammonia clouds. In the experiments, thin ice films of ammonia are coated with organic molecules, such as saturated and aromatic hydrocarbons, and characterized by infrared spectroscopy. Preliminary results indicate suppression of the ammonia absorption feature at 2.7 μ m by a thin layer of hydrocarbons. The implications for the spectral signatures of ammonia clouds in the atmospheres of Jupiter and Saturn will be discussed. Funding from the NSF Planetary Astronomy Program under grant AST-0206270 is gratefully acknowledged. The participation of Rhiannon Meharchand and Christina Baer was made possible by the NSF Research Experiences for Undergraduates Program under grant

  14. In support of descriptive studies; relevance to translational research

    PubMed Central

    Marincola, Francesco M

    2007-01-01

    The contemporary scientific establishment equates hypothesis testing to good science. This stance bypasses the preliminary need to identify a worthwhile hypothesis through rigorous observation of natural processes. If alleviation of human suffering is claimed as the goal of a scientific undertaking, it would be unfair to test a hypothesis whose relevance to human disease has not been satisfactorily proven. Here, we argue that descriptive investigations based on direct human observation should be highly valued and regarded essential for the selection of worthwhile hypotheses while the pursuit of costly scientific investigations without such evidence is a desecration of the cause upon which biomedical research is grounded. There are good things so in the tide pools and interesting thoughts to be generated from the seeing. Every new eye applied to the peephole which looks out at the world may fish in some new beauty and some new pattern, and the world of the human mind must be enriched by such fishing. John Steinbeck – Foreword to the Third Edition of Ed Ricketts' "Tides". PMID:17474987

  15. Exploring Young People's Perceptions Relevant to Counselling: A Qualitative Study.

    ERIC Educational Resources Information Center

    Le Surf, Anne; Lynch, Gordon

    1999-01-01

    Presents findings from a qualitative study exploring young people's perceptions about the provision of a youth-counseling service. Study reveals factors that hinder willingness to seek counseling and factors that encourage young people to make use of counseling. (Author/GCP)

  16. Study on thermal effects & sulfurized additives, in lubricating greases

    NASA Astrophysics Data System (ADS)

    Shah, Ami Atul

    Lithium Base grease constitutes about 50% of market. The greases are developed to be able to work in multiple working conditions and have longer working life. Greases with extreme pressure additives and anti-wear additives have been developed as a solution to many of the applications. These developed greases are tested under ASTM D2266 testing conditions to meet the requirements. The actual working conditions, although, differ than the real testing conditions. The loading, speed and temperature conditions can be more harsh, or fluctuating in nature. The cyclic nature of the parameters cannot be directly related to the test performance. For this purpose studies on the performance under spectrum loading, variable speed and fluctuating temperature must be performed. This study includes tests to understand the effect of thermal variation on some of the most commonly used grease additives that perform well under ASTM D2266 testing conditions. The studied additives include most widely used industrial extreme pressure additive MoS2. Performance of ZDDP which is trying to replace MoS2 in its industrial applications has also been studied. The tests cover study of extreme pressure, anti-wear and friction modifier additives to get a general idea on the effects of thermal variation in three areas. Sulphur is the most common extreme pressure additive. Sulphur based MoS 2 is extensively used grease additive. Study to understand the tribological performance of this additive through wear testing and SEM/EDX studies has been done. This performance is also studied for other metallic sulfides like WS2 and sulphur based organic compound. The aim is to study the importance of the type of bond that sulphur shares in its additive's structure on its performance. The MoS2 film formation is found to be on the basis of the FeS formation on the substrate and protection through sacrificial monolayer deposition of the MoS2 sheared structure. The free Mo then tends to oxidise. An attempt to

  17. Systematically Assessing the Situational Relevance of Electronic Knowledge Resources: A Mixed Methods Study

    PubMed Central

    Pluye, Pierre; Grad, Roland M.; Mysore, Naveen; Knaapen, Loes; Johnson-Lafleur, Janique; Dawes, Martin

    2007-01-01

    Electronic Knowledge Resources (EKRs) are increasingly used by physicians, but their situational relevance has not been systematically examined. Objective Systematically scrutinize the situational relevance of EKR-derived information items in and outside clinical settings. Background Physicians use EKRs to accomplish four cognitive objectives (C1-4), and three organizational objectives (O1-3): (C1) Answer questions/solve problems/support decision-making in a clinical context; (C2) fulfill educational-research objectives; (C3) search for personal interest or curiosity; (C4) overcome limits of human memory; (O1) share information with patients, families, or caregivers; (O2) exchange information with other health professionals; (O3) plan-manage-monitor tasks with other health professionals. Methods Longitudinal mixed methods multiple case study: Cases were 17 residents’ critical searches for information, using a commercial EKR, during a 2-month block of family practice. Usage data were automatically recorded. Each “opened” item of information was linked to an impact assessment questionnaire, and 1,981 evaluations of items were documented. Interviews with residents were guided by log files, which tracked use and impact of EKR-derived information items. Thematic analysis identified 156 critical searches linked to 877 information items. For each case, qualitative data were assigned to one of the seven proposed objectives. Results Residents achieved their search objectives in 85.9% of cases (situational relevance). Additional sources of information were sought in 52.6% of cases. Results support the seven proposed objectives, levels of comparative relevance (less, equally, more), and levels of stimulation of learning and knowledge (individual, organizational). Conclusion Our method of systematic assessment may contribute to user-based evaluation of EKRs. PMID:17600105

  18. Using guinea pigs in studies relevant to asthma and COPD

    PubMed Central

    Canning, Brendan J.; Chou, Yangling

    2010-01-01

    The guinea pig has been the most commonly used small animal species in preclinical studies related to asthma and COPD. The primary advantages of the guinea pig are the similar potencies and efficacies of agonists and antagonists in human and guinea pig airways and the many similarities in physiological processes, especially airway autonomic control and the response to allergen. The primary disadvantages to using guinea pigs are the lack of transgenic methods, limited numbers of guinea pig strains for comparative studies and a prominent axon reflex that is unlikely to be present in human airways. These attributes and various models developed in guinea pigs are discussed. PMID:18462968

  19. Laboratory studies of actinide partitioning relevant to 244Pu chronometry

    NASA Technical Reports Server (NTRS)

    Benjamin, T.; Heuser, W. R.; Burnett, D. S.

    1978-01-01

    Actinide partitioning and light lanthanide fractionation have been studied to gain an understanding of Pu chemistry under meteoritic and lunar conditions. The goal of the study was to identify conditions and samples from which chronological information can be retrieved. The laboratory investigations involved particle track radiography of the crystal/liquid partitioning of Th, U and Pu among diopsidic clinopyroxene, whitlockite and liquid. It is found that trivalent Pu plays an important role in partitioning for lunar and most meteoritic conditions. The use of Pu/Nd for relative age assessments is supported to some extent by the investigations; samples with unfractionated U, Th and Nd abundances (relative to average solar system values) may be suitable for Pu chronometry.

  20. Particle adhesion studies relevant to chemical mechanical polishing.

    PubMed

    Lu, Zhenyu; Ryde, Niels P; Babu, S V; Matijević, Egon

    2005-10-25

    This study describes particle adhesion experiments carried out to elucidate interactions between particles in slurries used for polishing of wafers and disks. For this purpose the packed column technique was employed, which simulated chemical mechanical polishing of copper with silica and alumina, as well as of silicic oxide with ceria. The model systems consisted of uniform copper and glass beads as collectors, representing the wafers, and colloidal dispersions of silica, alumia, and silica coated with nanosize ceria, all of well-defined properties that are used as abrasives. It was shown that a strong correlation exists between deposition and detachment results of the adhesion studies and the polish rates measured using actual substrates with the same or similar slurries.

  1. Surface studies relevant to silicon carbide chemical vapor deposition

    NASA Technical Reports Server (NTRS)

    Stinespring, C. D.; Wormhoudt, J. C.

    1989-01-01

    Reactions of C2H4, C3H8, and CH4 on the Si(111) surface and C2H4 on the Si(100) surface were investigated for surface temperatures in the range of 1062-1495 K. Results led to the identification of the reaction products, a characterization of the solid-state transport process, a determination of the nucleation mechanism and growth kinetics, and an assessment of orientation effects. Based on these results and on the modeling studies of Stinespring and Wormhoudt (1988) on the associated gas phase chemistry, a physical model for the two-step beta-SiC CVD process is proposed.

  2. Theoretical study of some experimentally relevant states of dysprosium

    SciTech Connect

    Dzuba, V. A.; Flambaum, V. V.

    2010-05-15

    Configuration interaction method is used to calculate transition amplitudes and other properties of the low states of dysprosium which are used in cooling and in the study of the time variation of the fine structure constant and violation of fundamental symmetries. The branching ratio for the cooling state to decay to states other than ground states is found to be smaller than 10{sup -4}. The matrix element of the weak interaction between degenerate states at E=19797.96 cm{sup -1} is about 4 Hz which is consistent with the experimental limit |H{sub W}|=|2.3{+-}2.9(stat.){+-}0.7(syst.)| Hz [A. T. Nguyen, D. Budker, D. DeMille, and M. Zolotorev, Phys. Rev. A 56, 3453 (1997)] and points to feasibility of its experimental measurement. Applications include the search for physics beyond the standard model using the parity nonconservation (PNC) isotopic chain approach.

  3. Laboratory Studies on Silicates Relevant for the Physics of TNOs

    NASA Astrophysics Data System (ADS)

    Brucato, John Robert; Strazzulla, Giovanni; Baratta, Giuseppe; Mennella, Vito; Colangeli, Luigi

    2003-06-01

    Silicates are one of the principal components present in Solar System objects. Silicates evolve in space modifying their physical properties according to the astronomical environments they go through. To characterise the nature of TNOs in the framework of the formation and evolution of the Solar System, experiments on structural transitions of silicates have been performed in the laboratory to simulate some of the processing suffered by the dust. The infrared spectral properties of possible silicate candidates thought to be present in TNOs have been studied. The results of thermal annealing of amorphous silicates and amorphisation of crystalline forsterite (pure-Mg olivine) by ion irradiation are presented. The observable properties of TNOs surfaces are inferred.

  4. Extracellular Vesicles: Composition, Biological Relevance, and Methods of Study

    PubMed Central

    Zaborowski, MikoŁaj P.; Balaj, Leonora; Breakefield, Xandra O.; Lai, Charles P.

    2015-01-01

    The release of extracellular vesicles (EVs), including exosomes and microvesicles, is a phenomenon shared by many cell types as a means of communicating with other cells and also potentially removing cell contents. The cargo of EVs includes the proteins, lipids, nucleic acids, and membrane receptors of the cells from which they originate. EVs released into the extracellular space can enter body fluids and potentially reach distant tissues. Once taken up by neighboring and/or distal cells, EVs can transfer functional cargo that may alter the status of recipient cells, thereby contributing to both physiological and pathological processes. In this article, we will focus on EV composition, mechanisms of uptake, and their biological effects on recipient cells. We will also discuss established and recently developed methods used to study EVs, including isolation, quantification, labeling and imaging protocols, as well as RNA analysis. PMID:26955082

  5. Surface Propensity of Atmospherically Relevant Amino Acids Studied by XPS.

    PubMed

    Mocellin, Alexandra; Gomes, Anderson Herbert de Abreu; Araújo, Oscar Cardoso; de Brito, Arnaldo Naves; Bjorneholm, Olle

    2017-03-30

    Amino acids constitute an important fraction of the water-soluble organic nitrogen (WSON) compounds in aerosols and are involved in many processes in the atmosphere. In this work, we applied XPS to study aqueous solutions of four amino acids: glycine, alanine, valine and methionine, in their zwitterionic forms. We found that amino acids with hydrophilic side chains and smaller size, GLY and ALA, tend to stay in the bulk of the liquid, while the hydrophobic and bigger amino acids, VAL and MET, are found to concentrate more on the surface. We found experimental evidences that the amino acids have preferential orientation relative to the surface, with the hydrophobic side chain being closer to the surface than the hydrophilic carboxylate group. The observed amino acid surface propensity has implications in atmospheric science as the surface interaction play a central role in cloud droplet formation, and they should be considered in climate models.

  6. Morphological study of fossa ovalis and its clinical relevance

    PubMed Central

    Joshi, S.D.; Chawre, H.K.; Joshi, S.S.

    2016-01-01

    Aims Patent foramen ovale (PFO) has been implicated in the etiology of a number of different pathologies, including cryptogenic stroke, decompression sickness in divers, etc. It can act as a channel for paradoxical embolism. PFO is not an uncommon condition, with a probe-patency in 15–35% population. The fossa ovalis (FOv) varies in size and shape from heart to heart; the prominence of annulus FOv also varies. The entire FOv may be redundant and aneurysmal. The anatomico-functional characterization of interatrial septum seems to be of paramount importance for both atrial septal defect (ASD) and PFO, not only for the device selection, but also for the evaluation of the outcome of this procedure. Method This study was conducted in 50 apparently normal hearts available in Department of Anatomy. After opening the right atrium, the shape of FOv was observed. The size was measured with the digital vernier caliper; the prominence and extent of limbus, and the redundancy or otherwise of FOv were noted; probe patency was confirmed. Results In the majority, FOv was oval (82%); average transverse diameter was 14.53 mm and vertical 12.60 mm. In 90%, the rim of the annulus was raised; in 20%, a recess was found deep to the margin of the annulus; and 18% showed probe patency. Conclusion As no study of this nature has been carried out in the Indian population, this provides pertinent information on the morphology of FOv, which may be useful for device selection in treating ASD and PFO. PMID:27133322

  7. Studies on Ammonia Spectral Signatures Relevant to Jupiter's Clouds

    NASA Astrophysics Data System (ADS)

    Oza, A. U.; Marschall, J.; Wong, M. H.; Kalogerakis, K. S.

    2006-12-01

    Observational evidence and thermochemical models indicate an abundance of ammonia ice clouds in Jupiter's atmosphere. However, spectrally identifiable ammonia ice clouds are found covering less than 1% of Jupiter's atmosphere, notably in turbulent areas [1,2]. Current literature suggests two possible explanations: coating by a hydrocarbon haze and/or photochemical processing ("tanning")[2,3]. We are pursuing a research program investigating the above hypotheses. In the experiments, thin films of ammonia ices are deposited in a cryogenic apparatus, coated with hydrocarbons, and characterized by infrared spectroscopy. The ice films can be irradiated by ultraviolet light to study their photochemistry. The spectroscopic measurements aim to identify the processes that control the optical properties of the ice mixtures and quantify their dependence on the identity of the coating, the temperature, and the ice composition. We have observed a consistent suppression of the ammonia absorption feature at 3 μm with coverage by thin layers of hydrocarbons. Modeling calculations of the multi-layer thin films assist in the interpretation of the experimental results and reveal the role of optical interference in masking the aforementioned ammonia spectral feature. The implications of these results for Jupiter's atmosphere will be discussed. Funding from the NSF Planetary Astronomy Program under grant AST-0206270 and from the NASA Outer Planets Research Program under grant NNG06GF37G is gratefully acknowledged. The participation of Anand Oza (Princeton University) was made possible by the NSF Research Experiences for Undergraduates Program under grant PHY-0353745. 1. S. K. Atreya, A.-S. Wong, K. H. Baines, M. H. Wong, T. C. Owen, Planet. Space Science 53, 498 (2005). 2. K. H. Baines, R. W. Carlson, and L. W. Kamp, Icarus 159, 74 (2002). 3. A.-S. Wong, Y. L. Yung, and A. J. Friedson, Geophys. Res. Lett. 30, 1447 (2003).

  8. Studies on Ammonia Spectral Signatures Relevant to Jupiter's Clouds

    NASA Astrophysics Data System (ADS)

    Kalogerakis, Konstantinos S.; Oza, A. U.; Marschall, J.; Wong, M. H.

    2006-09-01

    Observational evidence and thermochemical models indicate an abundance of ammonia ice clouds in Jupiter's atmosphere. However, spectrally identifiable ammonia ice clouds are found covering less than 1% of Jupiter's atmosphere, notably in turbulent areas [1,2]. Current literature suggests two possible explanations: coating by a hydrocarbon haze and/or photochemical processing ("tanning") [2,3]. We are pursuing a research program investigating the above hypotheses. In the experiments, thin films of ammonia ices are deposited in a cryogenic apparatus, coated with hydrocarbons, and characterized by infrared spectroscopy. The ice films can be irradiated by ultraviolet light to study their photochemistry. The spectroscopic measurements aim to identify the processes that control the optical properties of the ice mixtures and quantify their dependence on the identity of the coating, the temperature, and the ice composition. We have observed a consistent suppression of the ammonia absorption feature at 3 μm with coverage by thin layers of hydrocarbons. Modeling calculations of the multi-layer thin films assist in the interpretation of the experimental results and reveal the role of optical interference in masking the aforementioned ammonia spectral feature. The implications of these results for Jupiter's atmosphere will be discussed. Funding from the NSF Planetary Astronomy Program under grant AST-0206270 and from the NASA Outer Planets Research Program under grant NNG06GF37G is gratefully acknowledged. The participation of Anand Oza (Princeton University) was made possible by the NSF Research Experiences for Undergraduates Program under grant PHY-0353745. 1. S. K. Atreya, A.-S. Wong, K. H. Baines, M. H. Wong, T. C. Owen, Planet. Space Science 53, 498 (2005). 2. K. H. Baines, R. W. Carlson, and L. W. Kamp, Icarus 159, 74 (2002). 3. A.-S. Wong, Y. L. Yung, and A. J. Friedson, Geophys. Res. Lett. 30, 1447 (2003).

  9. Studies relevant to the design of reliable automotive electronics

    NASA Astrophysics Data System (ADS)

    Zeng, Hua

    This dissertation describes three independent studies related to the design of reliable automotive electronics. The topics covered are: the estimation of the radiated emissions from power bus structures, EM propagation of tire pressure monitoring systems (TPMS), and examinations of corrosion-induced faults in a connector. The first chapter describes a method for estimating the maximum possible radiated emissions from a printed circuit board power bus. An analysis based on a lossy cavity model is performed to determine the maximum possible radiated field corresponding to a given power bus noise voltage. A closed-form expression relating the maximum power bus noise voltage to the radiation peaks is then derived. This expression is solved in reverse to determine the minimum power bus voltage necessary to generate a radiated field and can be applied to measured values of power bus noise voltage to determine whether radiation directly from the power bus is potentially the emissions source. The second chapter identifies transmission parameters from a rotating tire and the vehicle body's effect on tire sensor transmission and propagation; relates these effects to receiver antenna packaging requirements; and then, based on these results, proposes the antenna design of employing car body as a part. In the new proposed TPMS design, a 20mm x 5mm loop antenna with a 40mm x 10mm slot beneath it is added to capture the surface currents of the car body and block the current path to increase the current density around the loop antenna. The simulation results show that this design exhibits a propagation factor 150 times larger than the traditional design. The third chapter investigates the effects of different contaminants (salt, oil, grease) on the shunt resistance between pins of a cable connector. The test results show that salt-induced corrosion and moisture may cause intermittent shunting resistances capable of affecting the normal operation of automotive systems. One

  10. Determining scanned body part from DICOM study description for relevant prior study matching.

    PubMed

    Mabotuwana, Thusitha; Qian, Yuechen

    2013-01-01

    The typical radiology reporting workflow involves the radiologist first looking at one or more relevant prior studies before interpreting the current study. To improve workflow efficiency, PACS systems can display relevant prior imaging studies, typically based on a study's anatomy as indicated in the Body Part Examined field of the DICOM header. The content of the Body Part Examined field can be very generic. For instance, an imaging study to exclude pancreatitis and another one to exclude renal stones will both have "abdomen" in their body part field, making it difficult to differentiate them. To improve prior study matching and support better study filtering, in this paper, we present a rule-based approach to determine specific body parts contained in the free-text DICOM Study Description field. Algorithms were trained using a production dataset of 1200 randomly selected unique study descriptions and validated against a test dataset of 404 study descriptions. Our validation resulted in 99.94% accuracy. The proposed technique suggests that a rule-based approach can be used for domain specific body part extraction from DICOM headers.

  11. Lexical Studies of Filipino Person Descriptors: Adding Personality-Relevant Social and Physical Attributes

    PubMed Central

    Imperio, Shellah Myra; Church, A. Timothy; Katigbak, Marcia S.; Reyes, Jose Alberto S.

    2009-01-01

    Lexical studies have focused on traits. In the Filipino language, we investigated whether additional dimensions can be identified when personality-relevant terms for social roles, statuses, and effects, plus physical attributes, are included. Filipino students (N = 496) rated themselves on 268 such terms, plus 253 markers of trait and evaluative dimensions. We identified 10 dimensions of social and physical attributes—Prominence, Uselessness, Attractiveness, Respectability, Uniqueness, Destructiveness, Presentableness, Strength, Dangerousness, and Charisma. Most of these dimensions did not correspond in a one-to-one manner to Filipino or alternative trait models (Big Five, HEXACO, ML7). However, considerable redundancy was observed between the social and physical attribute dimensions and trait and evaluative dimensions. Thus, social and physical attributes communicate information about personality traits, and vice-versa. PMID:19779603

  12. Lexical Studies of Filipino Person Descriptors: Adding Personality-Relevant Social and Physical Attributes.

    PubMed

    Imperio, Shellah Myra; Church, A Timothy; Katigbak, Marcia S; Reyes, Jose Alberto S

    2008-06-01

    Lexical studies have focused on traits. In the Filipino language, we investigated whether additional dimensions can be identified when personality-relevant terms for social roles, statuses, and effects, plus physical attributes, are included. Filipino students (N = 496) rated themselves on 268 such terms, plus 253 markers of trait and evaluative dimensions. We identified 10 dimensions of social and physical attributes-Prominence, Uselessness, Attractiveness, Respectability, Uniqueness, Destructiveness, Presentableness, Strength, Dangerousness, and Charisma. Most of these dimensions did not correspond in a one-to-one manner to Filipino or alternative trait models (Big Five, HEXACO, ML7). However, considerable redundancy was observed between the social and physical attribute dimensions and trait and evaluative dimensions. Thus, social and physical attributes communicate information about personality traits, and vice-versa.

  13. Teaching Social Studies for Newcomer English Language Learners: Toward Culturally Relevant Pedagogy

    ERIC Educational Resources Information Center

    Choi, Yoonjung

    2013-01-01

    Through this case study the author explores how an exemplary teacher utilized social studies curriculum and pedagogy to engage English language learners (ELLs) in learning in a culturally relevant and meaningful way and discusses practical implications for teaching and learning.

  14. Relevance Judging, Evaluation, and Decision Making in Virtual Libraries: A Descriptive Study.

    ERIC Educational Resources Information Center

    Fitzgerald, Mary Ann; Galloway, Chad

    2001-01-01

    Describes a study that investigated the cognitive processes undergraduates used to select information while using a virtual library, GALILEO (Georgia Library Learning Online). Discusses higher order thinking processes, relevance judging, evaluation (critical thinking), decision making, reasoning involving documents, relevance-related reasoning,…

  15. Ki-67 in endometrial cancer: scoring optimization and prognostic relevance for window studies

    PubMed Central

    Kitson, Sarah; Sivalingam, Vanitha N; Bolton, James; McVey, Rhona; Nickkho-Amiry, Mashid; Powell, Melanie E; Leary, Alexandra; Nijman, Hans W; Nout, Remi A; Bosse, Tjalling; Renehan, Andrew G; Kitchener, Henry C; Edmondson, Richard J; Crosbie, Emma J

    2017-01-01

    Ki-67, a marker of cellular proliferation, is increasingly being used in pre-surgical window studies in endometrial cancer as a primary outcome measure. Unlike in breast cancer, however, there are no guidelines standardizing its measurement and its clinical relevance as a response biomarker is undetermined. It is, therefore, imperative that Ki-67 scoring protocols are optimized and its association with patient survival rigorously evaluated, in order to be able to clinically interpret the results of these studies. Using the International Ki-67 in Breast Cancer Working Group guidelines as a basis, whole slide, hot spot and invasive edge scoring protocols were evaluated using endometrial biopsies and hysterectomy specimens from 179 women. Whole sections and tissue microarrays, manual and semi-automated scoring using Definiens Developer software were additionally compared. Ki-67 scores were related to clinicopathological variables and cancer-specific survival in uni- and multivariate analysis. Against criteria of time efficiency, intra- and inter-observer variability and consistency, semi-automated hot spot scoring was the preferred method. Ki-67 scores positively correlated with grade, stage and depth of myometrial invasion (P-values all <0.03). By univariate analysis, higher Ki-67 scores were associated with a significant reduction in cancer-specific survival (P≤0.05); however, this effect was substantially attenuated in the multivariate model. In conclusion, hot spot scoring of whole sections using Definiens is an optimal method to quantify Ki-67 in endometrial cancer window study specimens. Measured this way, it is a clinically relevant marker, though further work is required to determine whether reductions in Ki-67 in neoadjuvant intervention studies translate into improved patient outcome. PMID:27910946

  16. Ki-67 in endometrial cancer: scoring optimization and prognostic relevance for window studies.

    PubMed

    Kitson, Sarah; Sivalingam, Vanitha N; Bolton, James; McVey, Rhona; Nickkho-Amiry, Mashid; Powell, Melanie E; Leary, Alexandra; Nijman, Hans W; Nout, Remi A; Bosse, Tjalling; Renehan, Andrew G; Kitchener, Henry C; Edmondson, Richard J; Crosbie, Emma J

    2017-03-01

    Ki-67, a marker of cellular proliferation, is increasingly being used in pre-surgical window studies in endometrial cancer as a primary outcome measure. Unlike in breast cancer, however, there are no guidelines standardizing its measurement and its clinical relevance as a response biomarker is undetermined. It is, therefore, imperative that Ki-67 scoring protocols are optimized and its association with patient survival rigorously evaluated, in order to be able to clinically interpret the results of these studies. Using the International Ki-67 in Breast Cancer Working Group guidelines as a basis, whole slide, hot spot and invasive edge scoring protocols were evaluated using endometrial biopsies and hysterectomy specimens from 179 women. Whole sections and tissue microarrays, manual and semi-automated scoring using Definiens Developer software were additionally compared. Ki-67 scores were related to clinicopathological variables and cancer-specific survival in uni- and multivariate analysis. Against criteria of time efficiency, intra- and inter-observer variability and consistency, semi-automated hot spot scoring was the preferred method. Ki-67 scores positively correlated with grade, stage and depth of myometrial invasion (P-values all <0.03). By univariate analysis, higher Ki-67 scores were associated with a significant reduction in cancer-specific survival (P≤0.05); however, this effect was substantially attenuated in the multivariate model. In conclusion, hot spot scoring of whole sections using Definiens is an optimal method to quantify Ki-67 in endometrial cancer window study specimens. Measured this way, it is a clinically relevant marker, though further work is required to determine whether reductions in Ki-67 in neoadjuvant intervention studies translate into improved patient outcome.

  17. Benchmark Study of Industrial Needs for Additive Manufacturing in Finland

    NASA Astrophysics Data System (ADS)

    Lindqvist, Markku; Piili, Heidi; Salminen, Antti

    Additive manufacturing (AM) is a modern way to produce parts for industrial use. Even though the technical knowledge and research of AM processes are strong in Finland, there are only few industrial applications. Aim of this study is to collect practical knowledge of companies who are interested in industrial use of AM, especially in South-Eastern Finland. Goal of this study is also to investigate demands and requirements of applications for industrial use of AM in this area of Finland. It was concluded, that two of the reasons prohibiting wider industrial use of AM in Finland, are wrong expectations against this technology as well as lack of basic knowledge of possibilities of the technology. Especially, it was noticed that strong 3D-hype is even causing misunderstandings. Nevertheless, the high-level industrial know-how in the area, built around Finnish lumber industry is a strong foundation for the additive manufacturing technology.

  18. Electrostatic Levitation for Studies of Additive Manufactured Materials

    NASA Technical Reports Server (NTRS)

    SanSoucie, Michael P.; Rogers, Jan R.; Tramel, Terri

    2014-01-01

    The electrostatic levitation (ESL) laboratory at NASA's Marshall Space Flight Center is a unique facility for investigators studying high temperature materials. The laboratory boasts two levitators in which samples can be levitated, heated, melted, undercooled, and resolidified. Electrostatic levitation minimizes gravitational effects and allows materials to be studied without contact with a container or instrumentation. The lab also has a high temperature emissivity measurement system, which provides normal spectral and normal total emissivity measurements at use temperature. The ESL lab has been instrumental in many pioneering materials investigations of thermophysical properties, e.g., creep measurements, solidification, triggered nucleation, and emissivity at high temperatures. Research in the ESL lab has already led to the development of advanced high temperature materials for aerospace applications, coatings for rocket nozzles, improved medical and industrial optics, metallic glasses, ablatives for reentry vehicles, and materials with memory. Modeling of additive manufacturing materials processing is necessary for the study of their resulting materials properties. In addition, the modeling of the selective laser melting processes and its materials property predictions are also underway. Unfortunately, there is very little data for the properties of these materials, especially of the materials in the liquid state. Some method to measure thermophysical properties of additive manufacturing materials is necessary. The ESL lab is ideal for these studies. The lab can provide surface tension and viscosity of molten materials, density measurements, emissivity measurements, and even creep strength measurements. The ESL lab can also determine melting temperature, surface temperatures, and phase transition temperatures of additive manufactured materials. This presentation will provide background on the ESL lab and its capabilities, provide an approach to using the ESL

  19. Recommended Protocol for Round Robin Studies in Additive Manufacturing.

    PubMed

    Moylan, Shawn; Brown, Christopher U; Slotwinski, John

    2016-03-01

    One way to improve confidence and encourage proliferation of additive manufacturing (AM) technologies and parts is by generating more high quality data describing the performance of AM processes and parts. Many in the AM community see round robin studies as a way to generate large data sets while distributing the cost among the participants, thereby reducing the cost to individual users. The National Institute of Standards and Technology (NIST) has conducted and participated in several of these AM round robin studies. While the results of these studies are interesting and informative, many of the lessons learned in conducting these studies concern the logistics and methods of the study and unique issues presented by AM. Existing standards for conducting interlaboratory studies of measurement methods, along with NIST's experience, form the basis for recommended protocols for conducting AM round robin studies. The role of round robin studies in AM qualification, some of the limitations of round robin studies, and the potential benefit of less formal collaborative experiments where multiple factors, AM machine being only one, are varied simultaneously are also discussed.

  20. Recommended Protocol for Round Robin Studies in Additive Manufacturing

    PubMed Central

    Moylan, Shawn; Brown, Christopher U.; Slotwinski, John

    2016-01-01

    One way to improve confidence and encourage proliferation of additive manufacturing (AM) technologies and parts is by generating more high quality data describing the performance of AM processes and parts. Many in the AM community see round robin studies as a way to generate large data sets while distributing the cost among the participants, thereby reducing the cost to individual users. The National Institute of Standards and Technology (NIST) has conducted and participated in several of these AM round robin studies. While the results of these studies are interesting and informative, many of the lessons learned in conducting these studies concern the logistics and methods of the study and unique issues presented by AM. Existing standards for conducting interlaboratory studies of measurement methods, along with NIST’s experience, form the basis for recommended protocols for conducting AM round robin studies. The role of round robin studies in AM qualification, some of the limitations of round robin studies, and the potential benefit of less formal collaborative experiments where multiple factors, AM machine being only one, are varied simultaneously are also discussed. PMID:27274602

  1. Role of quantity of additional food to predators as a control in predator-prey systems with relevance to pest management and biological conservation.

    PubMed

    Srinivasu, P D N; Prasad, B S R V

    2011-10-01

    Necessity to understand the role of additional food as a tool in biological control programs is being increasingly felt, particularly due to its eco-friendly nature. A thorough mathematical analysis in this direction revealed the vital role of quality and quantity of the additional food in the controllability of the predator-prey systems. In this article controllability of the additional food--provided predator-prey system is studied from perspectives of pest eradication and biological conservation. Time optimal paths have been constructed to drive the state of the system to a desired terminal state by choosing quantity of the additional food as control variable. The theory developed in this article has been illustrated by solving problems related to pest eradication and biological conservation.

  2. Laboratory studies on N(2D) reactions of relevance to the chemistry of planetary atmospheres

    NASA Astrophysics Data System (ADS)

    Balucani, N.; Casavecchia, P.

    Molecular nitrogen is a very stable molecule, practically inert from a chemical point of view. For a nitrogen chemistry to occur in the planetary atmospheres which contain N2 , it is necessary to transform it into an active form, such as atoms or ions. As far as the production of atomic nitrogen in the upper atmospheres of planets (like Mars) or moons (like Titan) is concerned, several processes - as N2 dissociation induced by electron impact, EUV photolysis (λ <80 nm) and dissociative photoionization, or galactic cosmic ray absorption and N+ dissociative recombination all 2 lead to atomic nitrogen, notably in the ground, 4 S3/2 , and first electronically excited, 2 D3/2,5/2 , states with comparable yields. The radiative lifetimes of the metastable states 2 D3/2 and 2 D5/2 are quite long (12.3 and 48 hours, respectively), because the transition from a doublet to a quartet state is strongly forbidden. In addition, the physical quenching of N(2 D) is often a slow process and in some important cases the main fate of N(2 D) is chemical reaction with other constituents of the planetary atmospheres. The production of N atoms in the 2 D state is an important fact, because N(4 S) atoms exhibit very low reactivity with closed-shell molecules and the probability of collision with an open-shell radical is small. Unfortunately laboratory experiments on the gas-phase reactions of N(2 D) have been lacking until recently, because of serious experimental difficulties in studying these reactive systems. Accurate kinetic data on the reactions of N(2 D) with the some molecules of relevance to the chemistry of planetary atmospheres have finally become available in the late 90's, but a better knowledge of the reactive behavior requires a dynamical investigation of N(2 D) reactions. The capability of generating intense continuous beams of N(2 D) achieved in our laboratory some years ago has opened up the possibility of studying the reactive scattering of this species under single

  3. A Study of Novice Science Teachers' Conceptualizations of Culturally Relevant Pedagogy

    NASA Astrophysics Data System (ADS)

    Redman, Elizabeth Horst

    This qualitative study examined new science teachers' conceptualization of culturally relevant pedagogy (CRP). The study followed six novice science teachers from their preservice teaching placements into their first jobs as instructors of record, observing in their classrooms and interviewing them about their use of CRP. The study sought to understand (1) how the participating teachers conceptualize CRP in science, and (2) what challenges the teachers faced in trying to implement CRP. Findings suggest that the teachers conceptualized CRP in ways that were consistent with Enyedy, Danish and Fields' (2011) interpretations of relevance: relevance of authentic purpose, relevance of content and/or context, and relevance of practices. The teachers, however, translated those interpretations of relevance into their conceptualizations and classroom practice in a variety of ways. While they encountered difficulties in conceptualizing and practicing CRP, they also made productive moves in their practice and evidenced positive elements in their conceptualizations of CRP. In order to address the challenges these teachers faced in implementing CRP, I suggest an approach to teacher preparation in CRP that builds upon the understandings and productive moves the teachers evidenced in this study.

  4. Genotoxicity studies of the food additive ester gum.

    PubMed

    Mukherjee, A; Agarwal, K; Chakrabarti, J

    1992-07-01

    Ester gum (EG) is used in citrus oil-based beverage flavourings as a weighting or colouring agent. In the present study, concentrations of 50, 100 and 150 mg/kg body weight were administered orally to male Swiss albino mice, and sister chromatid exchange and chromosomal aberration were used as the cytogenetic endpoints to determine the genotoxic and clastogenic potential of the food additive. Although EG was weakly clastogenic and could induce a marginal increase in sister chromatid exchange frequencies, it was not a potential health hazard at the doses tested.

  5. Study of the interaction between indole-based compounds and biologically relevant G-quadruplexes.

    PubMed

    Carvalho, Josué; Nottelet, Pierre; Mergny, Jean-Louis; Queiroz, João A; Salgado, Gilmar F; Cruz, Carla

    2017-04-01

    G-quadruplexes (G4s) are high-order secondary structures that modulate several key cell processes such as telomere function, gene expression and DNA replication. In the past years G4s have emerged as promising targets for drug development due to the discovery of small molecules which bind and stabilize these structures. In this work, we report the synthesis of indole-based compounds and the study of their interaction with the biological relevant G4s c-MYC and human telomeric repeat 22AG using several biophysical techniques. The ligands are G4 specific and they can discriminate different G4 structures namely parallel and hybrid-1 topologies. The NMR study of interaction between the most promising indole-derivative (compound 3) and c-MYC quadruplex suggests that the ligand binds on the external tetrads with additional actions in the loops/grooves in a 2:1 ratio. The molecular docking calculations of compound 3 to c-MYC quadruplex corroborates with the (1)H and NOESY NMR studies. Overall, the results suggest that indole-based ligands are promising candidates for future lead optimizations in drug development.

  6. Transversal Traits in Science Education Research Relevant for Teaching and Research: A Meta-Interpretative Study

    ERIC Educational Resources Information Center

    Lopes, J. Bernardino; Silva, Antonio Alberto; Cravino, Jose P.; Costa, Nilza; Marques, Luis; Campos, Carlos

    2008-01-01

    This study is a meta-interpretative analysis that focuses on research conducted and published by other researchers. Concepts central to this study include global practical relevance, curriculum design, and formative situation. We analyzed 35 studies selected from 374 published studies in the years 2000 and 2001 in three journals referenced in the…

  7. Making intelligent systems team players: Additional case studies

    NASA Technical Reports Server (NTRS)

    Malin, Jane T.; Schreckenghost, Debra L.; Rhoads, Ron W.

    1993-01-01

    Observations from a case study of intelligent systems are reported as part of a multi-year interdisciplinary effort to provide guidance and assistance for designers of intelligent systems and their user interfaces. A series of studies were conducted to investigate issues in designing intelligent fault management systems in aerospace applications for effective human-computer interaction. The results of the initial study are documented in two NASA technical memoranda: TM 104738 Making Intelligent Systems Team Players: Case Studies and Design Issues, Volumes 1 and 2; and TM 104751, Making Intelligent Systems Team Players: Overview for Designers. The objective of this additional study was to broaden the investigation of human-computer interaction design issues beyond the focus on monitoring and fault detection in the initial study. The results of this second study are documented which is intended as a supplement to the original design guidance documents. These results should be of interest to designers of intelligent systems for use in real-time operations, and to researchers in the areas of human-computer interaction and artificial intelligence.

  8. Cytotoxicity of Au, ZnO and SiO₂ NPs using in vitro assays with mussel hemocytes and gill cells: Relevance of size, shape and additives.

    PubMed

    Katsumiti, Alberto; Arostegui, Inmaculada; Oron, Miriam; Gilliland, Douglas; Valsami-Jones, Eugenia; Cajaraville, Miren P

    2016-01-01

    Metal-bearing nanoparticles (NPs) possess unique physico-chemical characteristics that make them useful for an increasing number of industrial products and applications, but could also confer them a higher toxicity due to their higher reactivity compared to bulk forms of the same materials. There is a considerable interest in the use of in vitro techniques in environmentally relevant species, such as marine mussels, to evaluate NPs toxicity. In the present work, mussel hemocytes and gill cells were used to assess the potential toxic effects of Au, ZnO and SiO2 NPs with different sizes and shapes in parallel with their respective ionic and bulk forms and additives used in the NPs preparations. Cytotoxicity (neutral red and MTT assays) was screened at a wide range of concentrations, and LC50 values were calculated. Uptake of fluorescently labeled SIO2 NPs of 27 nm by hemocytes was also investigated. Au, ZnO and SiO2 NPs were less toxic than the corresponding ionic forms but more toxic than the bulk forms. ZnO NPs were the most toxic NPs tested which could be related with their capacity to release free ions. SiO2 NPs were not taken up by hemocytes and were not toxic to either hemocytes or gill cells. Size-dependent toxicity was found for Au NPs. Shape influenced the cytotoxicity of ZnO NPs. Finally, the presence of the additives Na-citrate and Ecodis P90 contributed to the toxicity of Au and ZnO NPs, respectively. As a general conclusion, solubility appears to play a key role in NPs toxicity to mussel cells.

  9. Additive Manufacturing Materials Study for Gaseous Radiation Detection

    SciTech Connect

    Steer, C.A.; Durose, A.; Boakes, J.

    2015-07-01

    Additive manufacturing (AM) techniques may lead to improvements in many areas of radiation detector construction; notably the rapid manufacturing time allows for a reduced time between prototype iterations. The additive nature of the technique results in a granular microstructure which may be permeable to ingress by atmospheric gases and make it unsuitable for gaseous radiation detector development. In this study we consider the application of AM to the construction of enclosures and frames for wire-based gaseous radiation tracking detectors. We have focussed on oxygen impurity ingress as a measure of the permeability of the enclosure, and the gas charging and discharging curves of several simplistic enclosure shapes are reported. A prototype wire-frame is also presented to examine structural strength and positional accuracy of an AM produced frame. We lastly discuss the implications of this study for AM based radiation detection technology as a diagnostic tool for incident response scenarios, such as the interrogation of a suspect radiation-emitting package. (authors)

  10. RAMSEYS DRAFT WILDERNESS STUDY AREA AND ADDITION, VIRGINIA.

    USGS Publications Warehouse

    Lesure, Frank G.; Mory, Peter C.

    1984-01-01

    Mineral-resource surveys of the Ramseys Draft Wilderness Study Area and adjoining roadless area addition in George Washington National Forest in the western valley and ridge province, Augusta and Highland Counties, Virginia, were done. The surveys outlined three small areas containing anomalous amounts of copper, lead, and zinc related to stratabound red-bed copper mineralization, but these occurrences are not large and are not considered as having mineral-resource potential. The area contains abundant sandstone suitable for construction materials and shale suitable for making brick, tile, and other low-grade ceramic products, but these commodities occur in abundance outside the wilderness study area. Structural conditions are probably favorable for the accumulation of natural gas, but exploratory drilling has not been done sufficiently near the area to evaluate the gas potential.

  11. Growth and photoluminescence study of several single crystal segments relevant to monolithic semiconductor cascade solar cells

    NASA Astrophysics Data System (ADS)

    Sillmon, Roger S.; Schreiner, Anton F.; Timmons, Michael

    1983-09-01

    Several representative single crystal stacked layers of III-V compound and alloy semiconductors were grown which are spatial regions relevant to a monolithic cascade solar cell, including the substrate, n-GaAs(Si), which was pre-growth heat treated in H 2(g) prior to its use. These structures were then studied by cryogenic laser excited photoluminescence (PL), and the substrate portion was explored in a depth profiling mode. Within the forbidden band gap region up to seven recombinations were observed and identified for undoped GaAs layers or the GaAs(Si) substrate, and several other PL recombinations were observed for undoped Al xGa 1- xAs and Al yGa 1- ySb zAs 1- z layers. In addition to the valence and conduction bands, these optical bands are also associa ted with the presence of C Ga, Si Ga, Si As, Cu Ga, V As, V Ga and vacancy-impurity complexes involving several of these defect types even in the absence of intentional doping. The findings also relate to problems of self-compensation and type inversion, so that the need for growth modifications is indicated.

  12. Using Relevance Prompts: An Exploratory Study to Promote Eighth Graders' Comprehension and Retelling of Narrative Text

    ERIC Educational Resources Information Center

    Fogarty, Melissa S.; Davis, John L.; Anderson, Leah L.; Myint, Ahmarlay

    2017-01-01

    This exploratory study investigated the effects of modifying eighth grade students' purposes for reading through a prompt designed to increase engagement with the text. The current study was conducted using a randomized between-subjects design, with a relevance prompt as the between-subjects factor and reader proficiency as a covariate. A sample…

  13. Total Absorption Study of Beta Decays Relevant for Nuclear Applications and Nuclear Structure

    SciTech Connect

    Algora, A.; Valencia, E.; Taín, J.L.; Jordan, M.D.; Agramunt, J.; Rubio, B.; Estevez, E.; Molina, F.; Montaner, A.; Guadilla, V.; Fallot, M.; Porta, A.; Zakari-Issoufou, A.-A.; Bui, V.M.; and others

    2014-06-15

    An overview is given of our activities related to the study of the beta decay of neutron rich nuclei relevant for nuclear applications. Recent results of the study of the beta decay of {sup 87,88}Br using a new segmented total absorption spectrometer are presented. The measurements were performed at the IGISOL facility using trap-assisted total absorption spectroscopy.

  14. Total Absorption Study of Beta Decays Relevant for Nuclear Applications and Nuclear Structure

    SciTech Connect

    Algora, A.; Valencia, E.; Tain, J. L.; Jordan, M. D.; Agramunt, J.; Rubio, B.; Estevez, E.; Molina, F.; Montaner, A.; Guadilla, V.; Fallot, M.; Podolyak, Zs.; Regan, P. H.; Gelletly, W.; Bowry, M.; Mason, P.; Farrelly, G. F.; Rissanen, J.; Eronen, T.; Moore, I.; Penttila, H.; Aysto, J.; Eloma, V.; Hakala, J.; Jokinen, A.; Kolkinen, V.; Reponen, M.; Sonnenschein, V.; Cano-Ott, D.; Martinez, T.; Mendoza, E.; Garcia, A. R.; Gomez-Hornillos, M. B.; Gorlychev, V.; Caballero-Folch, R.; Kondev, F. G.; Sonzogni, A. A.

    2014-06-01

    We present an overview of our activities related to the study of the beta decay of neutron rich nuclei relevant for nuclear applications. Recent results of the study of the beta decay of Br using a new segmented total absorption spectrometer are presented. Our measurements were performed at the IGISOL facility using trap-assisted total absorption spectroscopy.

  15. The Golden Retriever Lifetime Study: establishing an observational cohort study with translational relevance for human health

    PubMed Central

    Guy, Michael K.; Page, Rodney L.; Jensen, Wayne A.; Olson, Patricia N.; Haworth, J. David; Searfoss, Erin E.; Brown, Diane E.

    2015-01-01

    The Golden Retriever Lifetime Study (GRLS) is the first prospective longitudinal study attempted in veterinary medicine to identify the major dietary, genetic and environmental risk factors for cancer and other important diseases in dogs. The GRLS is an observational study that will follow a cohort of 3000 purebred Golden Retrievers throughout their lives via annual online questionnaires from the dog owner and annual physical examinations and collection of biological samples by the primary care veterinarian. The field of comparative medicine investigating naturally occurring disorders in pets is specifically relevant to the many diseases that have a genetic basis for disease in both animals and humans, including cancer, blindness, metabolic and behavioural disorders and some neurodegenerative disorders. The opportunity for the GRLS to provide high-quality data for translational comparative medical initiatives in several disease categories is great. In particular, the opportunity to develop a lifetime dataset of lifestyle and activity, environmental exposure and diet history combined with simultaneous annual biological sample sets and detailed health outcomes will provide disease incidence data for this cohort of geographically dispersed dogs and associations with a wide variety of potential risk factors. The GRLS will provide a lifetime historical context, repeated biological sample sets and outcomes necessary to interrogate complex associations between genes and environmental influences and cancer. PMID:26056371

  16. Deliberate practice theory: perceived relevance, effort, and inherent enjoyment of music practice: study II.

    PubMed

    Hyllegard, Randy; Bories, Tamara L

    2009-10-01

    This study, based on the theory of deliberate practice, examined the practice relevance, effort, and inherent enjoyment aspects of the theory. 25 college undergraduates practiced playing a melody on an electronic keyboard for three 20-min. practice sessions. Following each session, the perceived relevance of the practice for improving performance of the melody, the effort needed to learn the melody, and the inherent enjoyment of the practice were each rated on 10-point scales. Findings were consistent with theory and similar to previous studies also involving music practice and other tasks.

  17. Experimental Study of Additives on Viscosity biodiesel at Low Temperature

    NASA Astrophysics Data System (ADS)

    Fajar, Berkah; Sukarno

    2015-09-01

    An experimental investigation was performed to find out the viscosity of additive and biodiesel fuel mixture in the temperature range from 283 K to 318 K. Solutions to reduce the viscosity of biodiesel is to add the biodiesel with some additive. The viscosity was measured using a Brookfield Rheometer DV-II. The additives were the generic additive (Diethyl Ether/DDE) and the commercial additive Viscoplex 10-330 CFI. Each biodiesel blends had a concentration of the mixture: 0.0; 0.25; 0.5; 0.75; 1.0; and 1.25% vol. Temperature of biodiesel was controlled from 40°C to 0°C. The viscosity of biodiesel and additive mixture at a constant temperature can be approximated by a polynomial equation and at a constant concentration by exponential equation. The optimum mixture is at 0.75% for diethyl ether and 0.5% for viscoplex.

  18. Additive Manufacturing in Production: A Study Case Applying Technical Requirements

    NASA Astrophysics Data System (ADS)

    Ituarte, Iñigo Flores; Coatanea, Eric; Salmi, Mika; Tuomi, Jukka; Partanen, Jouni

    Additive manufacturing (AM) is expanding the manufacturing capabilities. However, quality of AM produced parts is dependent on a number of machine, geometry and process parameters. The variability of these parameters affects the manufacturing drastically and therefore standardized processes and harmonized methodologies need to be developed to characterize the technology for end use applications and enable the technology for manufacturing. This research proposes a composite methodology integrating Taguchi Design of Experiments, multi-objective optimization and statistical process control, to optimize the manufacturing process and fulfil multiple requirements imposed to an arbitrary geometry. The proposed methodology aims to characterize AM technology depending upon manufacturing process variables as well as to perform a comparative assessment of three AM technologies (Selective Laser Sintering, Laser Stereolithography and Polyjet). Results indicate that only one machine, laser-based Stereolithography, was feasible to fulfil simultaneously macro and micro level geometrical requirements but mechanical properties were not at required level. Future research will study a single AM system at the time to characterize AM machine technical capabilities and stimulate pre-normative initiatives of the technology for end use applications.

  19. Relevance Revisited: Curriculum Development in the Humanities. No. III: Humanists and Policy Studies.

    ERIC Educational Resources Information Center

    French, Roderick S., Ed.

    Papers presented at a March 1977 workshop that examined issues raised by the participation of academic humanists and other humanistically oriented academics in policy research and teaching are provided. Section I contains three background papers: "The Humanist, Technology, and Policy Studies," by Joseph W. Slade; "The Relevance of…

  20. Principal Documents Issued by the Ministry of Education and Relevant Departments Concerning Study-Abroad Work

    ERIC Educational Resources Information Center

    Chinese Education and Society, 2005

    2005-01-01

    In the past twenty-five years, the Ministry of Education of the Republic of China and relevant departments have formulated a total of more than 400 documents with regard to the selection and sending of personnel for studies abroad, management abroad, work after returning to China, serving the country, convenience in entering and exiting China's…

  1. Contact allergy to colophony. Clinical and experimental studies with emphasis on clinical relevance.

    PubMed

    Färm, G

    1998-01-01

    Colophony--also called rosin--is a material obtained from coniferous trees. It is used widely in many products, particularly because of its good tackifying properties. Colophony is also used in paper sizing to increase water resistance. Colophony may cause contact allergy, and around 5% of Swedish dermatitis patients show allergic reactions to colophony at patch testing. There are many case reports of colophony in different products causing contact dermatitis. Often, however, the clinical relevance of a positive patch-test reaction to colophony is difficult to evaluate. The principal aims of the present thesis were to study the prevalence of contact allergy to colophony and of skin disease in individuals with an occupational exposure to colophony; to study the prognosis of dermatitis in colophony-sensitive subjects, and to investigate the outcome of repeated open applications of colophony, thereby trying to elucidate the clinical relevance of contact allergy to colophony. Employees of a tall-oil rosin (colophony) factory (n = 180), and of an opera company where colophony was used in dancers' rosin, mascara and wig glues (n = 132), were interviewed, examined and patch tested. 3.9% and 2% of these two groups respectively had a positive patch test to colophony. More than every fourth participant showed some kind of skin disease, but only few cases were related to work. Eighty-three patients with previously diagnosed contact allergy to colophony were followed-up 72% showed a positive patch-test reaction to colophony at re-testing. Around one third had hand eczema. There was no significant correlation between colophony exposure and current hand eczema. Adhesive bandages containing colophony and zinc oxide (ZnO), colophony and mixes of colophony and ZnO, were tested in 7 colophony-sensitive subjects to see whether addition of zinc oxide inhibited elicitation of allergic dermatitis to colophony, which has been proposed. No difference in reactivity between colophony and

  2. Dose addition models based on biologically-relevant reductions in fetal testosterone accurately predict postnatal reproductive tract alterations by a phthalate mixture in rats

    EPA Science Inventory

    Challenges in cumulative risk assessment of anti-androgenic phthalate mixtures include a lack of data on all the individual phthalates and difficulty determining the biological relevance of reduction in fetal testosterone (T) on postnatal development. The objectives of the curren...

  3. A solution study of silica condensation and speciation with relevance to in vitro investigations of biosilicification.

    PubMed

    Belton, David J; Deschaume, Olivier; Patwardhan, Siddharth V; Perry, Carole C

    2010-08-12

    Requiring mild synthesis conditions and possessing a high level of organization and functionality, biosilicas constitute a source of wonder and inspiration for both materials scientists and biologists. In order to understand how such biomaterials are formed and to apply this knowledge to the generation of novel bioinspired materials, a detailed study of the materials, as formed under biologically relevant conditions, is required. In this contribution, data from a detailed study of silica speciation and condensation using a model bioinspired silica precursor (silicon catechol complex, SCC) is presented. The silicon complex quickly and controllably dissociates under neutral pH conditions to well-defined, metastable solutions of orthosilicic acid. The formation of silicomolybdous (blue) complexes was used to monitor and study different stages of silicic acid condensation. In parallel, the rates of silicomolybdic (yellow) complex formation, with mathematical modeling of the species present, was used to follow the solution speciation of polysilicic acids. The results obtained from the two assays correlate well. Monomeric silicic acid, trimeric silicic acids, and different classes of oligomeric polysilicic acids and silica nuclei can be identified and their periods of stability during the early stages of silica condensation measured. For experiments performed at a range of temperatures (273-323 K), an activation energy of 77 kJ.mol(-1) was obtained for the formation of trimers. The activation energies for the forward and reverse condensation reactions for addition of monomers to polysilicic acids (273-293 +/- 1 K) were 55.0 and 58.6 kJ.mol(-1), respectively. For temperatures above 293 K, these energies were reduced to 6.1 and 7.3 kJ.mol(-1), indicating a probable change in the prevailing condensation mechanism. The impact of pH on the rates of condensation were measured. There was a direct correlation between the apparent third-order rate constant for trimer formation

  4. Studies of the surface reactivity of metal oxyhydroxides and sulfides with relevance to environmental chemistry

    NASA Astrophysics Data System (ADS)

    Pierre-Louis, Andro-Marc

    With the benefits of an ever increasing advance of industrialization around the globe come formidable environmental problems. Three environmental problems that have relevance to the research described in this thesis are the 1) buildup of atmospheric CO2 gas through the burning of fossil fuels, 2) eutrophication of aquatic systems, and 3) the acidification of environments from acid mine drainage (AMD) resulting from coal-mining activities. In particular research is presented in this thesis that investigated the surface chemistry of CO2 and phosphate (PO43-) on a suite of environmentally relevant iron oxyhydroxide materials and the chemistry of phospholipid molecules on environmentally relevant iron sulfide surfaces to suppress AMD. To develop a microscopic understanding of the surface chemistry of the different systems, an array of experimental and computational techniques were used in the research. Techniques included X-ray photoelectron spectroscopy, atomic adsorption, X-ray diffraction, scanning transmission microscopy with electron dispersive X-ray spectroscopy (STEM/EDS), ion chromatography (IC), and attenuated total reflectance Fourier transform Infrared (ATR-FTIR). Results from the latter technique were interpreted with the aid of density function theory (DFT) calculations. Iron oxyhydroxides, which consisted of ferrihydrite (FeOOH), goethite (α-FeOOH), ferrimagnetic ferrihydrite (FerriFh), and aluminum-doped iron oxyhydroxide (content from 0-100 mol%) were synthesized and studied before and after exposure to gaseous CO2, CO32-, and PO43- species. FeOOH and mixed Al/Fe oxyhydroxide surfaces showed high affinities for the formation of carbonate and bicarbonate species upon exposure to gaseous CO2. Within the Al/Fe oxyhydroxide circumstance, a low Al level of incorporation in the iron oxyhydroxide structure caused a slight increase in surface area and increase in the amount of oxyanion (e.g., CO32- or PO43-) adsorption up to an Al level of 30 mol%. Significant

  5. Impact analysis studies of clinical prediction rules relevant to primary care: a systematic review

    PubMed Central

    Wallace, Emma; Uijen, Maike J M; Clyne, Barbara; Zarabzadeh, Atieh; Keogh, Claire; Galvin, Rose; Smith, Susan M; Fahey, Tom

    2016-01-01

    Objectives Following appropriate validation, clinical prediction rules (CPRs) should undergo impact analysis to evaluate their effect on patient care. The aim of this systematic review is to narratively review and critically appraise CPR impact analysis studies relevant to primary care. Setting Primary care. Participants Adults and children. Intervention Studies that implemented the CPR compared to usual care were included. Study design Randomised controlled trial (RCT), controlled before–after, and interrupted time series. Primary outcome Physician behaviour and/or patient outcomes. Results A total of 18 studies, incorporating 14 unique CPRs, were included. The main study design was RCT (n=13). Overall, 10 studies reported an improvement in primary outcome with CPR implementation. Of 6 musculoskeletal studies, 5 were effective in altering targeted physician behaviour in ordering imaging for patients presenting with ankle, knee and neck musculoskeletal injuries. Of 6 cardiovascular studies, 4 implemented cardiovascular risk scores, and 3 reported no impact on physician behaviour outcomes, such as prescribing and referral, or patient outcomes, such as reduction in serum lipid levels. 2 studies examined CPRs in decision-making for patients presenting with chest pain and reduced inappropriate admissions. Of 5 respiratory studies, 2 were effective in reducing antibiotic prescribing for sore throat following CPR implementation. Overall, study methodological quality was often unclear due to incomplete reporting. Conclusions Despite increasing interest in developing and validating CPRs relevant to primary care, relatively few have gone through impact analysis. To date, research has focused on a small number of CPRs across few clinical domains only. PMID:27008685

  6. Study of photoacoustic measurement of bone health based on clinically relevant models

    NASA Astrophysics Data System (ADS)

    Feng, Ting; Kozloff, Ken; Cao, Meng; Cheng, Qian; Yuan, Jie; Wang, Xueding

    2016-02-01

    Photoacoustic (PA) technique involving both ultrasound and light has been explored for potential application in the assessment of bone health. The optical and ultrasound penetration in bone have been studied. The feasibility of conducting 3D PA imaging of bone, and performing quantitative evaluation of bone microstructures by using photoacoustic spectrum analysis (PASA) has also been investigated. The findings from the experiments demonstrate that PA measurement could offer information of bone mineral density and bone microstructure, both relevant to bone health.

  7. Additive empirical parametrization and microscopic study of deuteron breakup

    NASA Astrophysics Data System (ADS)

    Avrigeanu, M.; Avrigeanu, V.

    2017-02-01

    Comparative assessment of the total breakup proton-emission cross sections measured for 56 MeV deuteron interaction with target nuclei from 12C to 209Bi, with an empirical parametrization and recently calculated microscopic neutron-removal cross sections was done at the same time with similar data measured at 15, 25.5, 70, and 80 MeV. Comparable mass dependencies of the elastic-breakup (EB) cross sections provided by the empirical parametrization and the microscopic results have been also found at the deuteron energy of 56 MeV, while the assessment of absolute-values variance up to a factor of two was not possible because of the lack of EB measurements at energies higher than 25.5 MeV. While the similarities represent an additional validation of the microscopic calculations, the cross-section difference should be considered within the objectives of further measurements.

  8. NMR relaxometry study of plaster mortar with polymer additives

    SciTech Connect

    Jumate, E.; Manea, D.; Moldovan, D.; Fechete, R.

    2013-11-13

    The cement mixed with water forms a plastic paste or slurry which stiffness in time and finally hardens into a resistant stone. The addition of sand aggregates, polymers (Walocel) and/or calcium carbonate will modify dramatically the final mortar mechanic and thermal properties. The hydration processes can be observed using the 1D NMR measurements of transverse T{sub 2} relaxation times distributions analysed by a Laplace inversion algorithm. These distributions were obtained for mortar pasta measured at 2 hours after preparation then at 3, 7 and 28 days after preparation. Multiple components are identified in the T{sub 2} distributions. These can be associated with the proton bounded chemical or physical to the mortar minerals characterized by a short T{sub 2} relaxation time and to water protons in pores with three different pore sizes as observed from SEM images. The evaporation process is faster in the first hours after preparation, while the mortar hydration (bonding of water molecules to mortar minerals) can be still observed after days or months from preparation. Finally, the mechanic resistance was correlated with the transverse T{sub 2} relaxation rates corresponding to the bound water.

  9. The relevance of using 3D cell cultures, in addition to 2D monolayer cultures, when evaluating breast cancer drug sensitivity and resistance

    PubMed Central

    Breslin, Susan; O'Driscoll, Lorraine

    2016-01-01

    Solid tumours naturally grow in 3D wherein the spatial arrangement of cells affects how they interact with each other. This suggests that 3D cell culture may mimic the natural in vivo setting better than traditional monolayer (2D) cell culture, where cells are grown attached to plastic. Here, using HER2-positive breast cancer cell lines as models (BT474, HCC1954, EFM192A), the effects of culturing cells in 3D using the poly-HEMA method compared to 2D cultures were assessed in terms of cellular viability, response/resistance to anti-cancer drugs, protein expression and enzyme activity. Scanning electron microscopy showed the morphology of cells in 3D to be substantially different to those cultured in 2D. Cell viability in 3D cells was substantially lower than that of cells in 2D cultures, while 3D cultures were more resistant to the effects of HER-targeted (neratinib) and classical chemotherapy (docetaxel) drugs. Expression of proteins involved in cell survival, transporters associated with drug resistance and drug targets were increased in 3D cultures. Finally, activity of drug metabolising enzyme CYP3A4 was substantially increased in 3D compared to 2D cultures. Together this data indicates that the biological information represented by 3D and 2D cell cultures is substantially different i.e. 3D cell cultures demonstrate higher innate resistance to anti-cancer drugs compared to 2D cultures, which may be facilitated by the altered receptor proteins, drug transporters and metabolising enzyme activity. This highlights the importance of considering 3D in addition to 2D culture methods in pre-clinical studies of both newer targeted and more traditional anti-cancer drugs. PMID:27304190

  10. The relevance of using 3D cell cultures, in addition to 2D monolayer cultures, when evaluating breast cancer drug sensitivity and resistance.

    PubMed

    Breslin, Susan; O'Driscoll, Lorraine

    2016-07-19

    Solid tumours naturally grow in 3D wherein the spatial arrangement of cells affects how they interact with each other. This suggests that 3D cell culture may mimic the natural in vivo setting better than traditional monolayer (2D) cell culture, where cells are grown attached to plastic. Here, using HER2-positive breast cancer cell lines as models (BT474, HCC1954, EFM192A), the effects of culturing cells in 3D using the poly-HEMA method compared to 2D cultures were assessed in terms of cellular viability, response/resistance to anti-cancer drugs, protein expression and enzyme activity. Scanning electron microscopy showed the morphology of cells in 3D to be substantially different to those cultured in 2D. Cell viability in 3D cells was substantially lower than that of cells in 2D cultures, while 3D cultures were more resistant to the effects of HER-targeted (neratinib) and classical chemotherapy (docetaxel) drugs. Expression of proteins involved in cell survival, transporters associated with drug resistance and drug targets were increased in 3D cultures. Finally, activity of drug metabolising enzyme CYP3A4 was substantially increased in 3D compared to 2D cultures. Together this data indicates that the biological information represented by 3D and 2D cell cultures is substantially different i.e. 3D cell cultures demonstrate higher innate resistance to anti-cancer drugs compared to 2D cultures, which may be facilitated by the altered receptor proteins, drug transporters and metabolising enzyme activity. This highlights the importance of considering 3D in addition to 2D culture methods in pre-clinical studies of both newer targeted and more traditional anti-cancer drugs.

  11. TDS exposure project: relevance of the total diet study approach for different groups of substances.

    PubMed

    Vin, Karine; Papadopoulos, Alexandra; Cubadda, Francesco; Aureli, Federica; Oktay Basegmez, Hatice Imge; D'Amato, Marilena; De Coster, Sam; D'Evoli, Laura; López Esteban, María Teresa; Jurkovic, Martina; Lucarini, Massimo; Ozer, Hayrettin; Fernández San Juan, Pedro Mario; Sioen, Isabelle; Sokolic, Darja; Turrini, Aida; Sirot, Véronique

    2014-11-01

    A method to validate the relevance of the Total Diet Study (TDS) approach for different types of substances is described. As a first step, a list of >2800 chemicals classified into eight main groups of relevance for food safety (natural components, environmental contaminants, substances intentionally added to foods, residues, naturally occurring contaminants, process contaminants, contaminants from packaging and food contact materials, other substances) has been established. The appropriateness of the TDS approach for the different substance groups has then been considered with regard to the three essential principles of a TDS: representativeness of the whole diet, pooling of foods and food analyzed as consumed. Four criteria were considered for that purpose (i) the substance has to be present in a significant part of the diet or predominantly present in specific food groups, (ii) a robust analytical method has to be available to determine it in potential contributors to the dietary exposure of the population, and (iii) the dilution impact of pooling and (iv) the impact of everyday food preparation methods on the concentration of the substance are assessed. For most of the substances the TDS approach appeared to be relevant and any precautions to be taken are outlined.

  12. The effects of study-task relevance on perceptual repetition priming

    NASA Technical Reports Server (NTRS)

    Holbrook, Jon B.; Bost, Preston R.; Cave, Carolyn Backer

    2003-01-01

    Repetition priming is easily elicited in many traditional paradigms, and the possibility that perceptual priming may be other than an automatic consequence of perception has received little consideration. This issue is explored in two experiments. In Experiment 1, participants named the target from a four-item category search study task more quickly than the nontarget study items at a later naming test. Experiment 2 extended this finding to conditions in which stimuli were individually presented at study. In three different study tasks, stimuli relevant to study-task completion elicited priming on a later test, but stimuli presented outside the context of a task did not. In both experiments, recognition was above chance for nonrelevant stimuli, suggesting that participants explicitly remembered stimuli that did not elicit priming. Results suggest that priming is sensitive to study-task demands and may reflect a more adaptive and flexible mechanism for modification of perceptual processing than previously appreciated.

  13. Additional EIPC Study Analysis: Interim Report on High Priority Topics

    SciTech Connect

    Hadley, Stanton W

    2013-11-01

    Between 2010 and 2012 the Eastern Interconnection Planning Collaborative (EIPC) conducted a major long-term resource and transmission study of the Eastern Interconnection (EI). With guidance from a Stakeholder Steering Committee (SSC) that included representatives from the Eastern Interconnection States Planning Council (EISPC) among others, the project was conducted in two phases. Phase 1 involved a long-term capacity expansion analysis that involved creation of eight major futures plus 72 sensitivities. Three scenarios were selected for more extensive transmission- focused evaluation in Phase 2. Five power flow analyses, nine production cost model runs (including six sensitivities), and three capital cost estimations were developed during this second phase. The results from Phase 1 and 2 provided a wealth of data that could be examined further to address energy-related questions. A list of 13 topics was developed for further analysis; this paper discusses the first five.

  14. Additional studies for the spectrophotometric measurement of iodine in water

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Previous work in iodine spectroscopy is briefly reviewed. Continued studies of the direct spectrophotometric determination of aqueous iodine complexed with potassium iodide show that free iodine is optimally determined at the isosbestic point for these solutions. The effects on iodine determinations of turbidity and chemical substances (in trace amounts) is discussed and illustrated. At the levels tested, iodine measurements are not significantly altered by such substances. A preliminary design for an on-line, automated iodine monitor with eventual capability of operating also as a controller was analyzed and developed in detail with respect single beam colorimeter operating at two wavelengths (using a rotating filter wheel). A flow-through sample cell allows the instrument to operate continuously, except for momentary stop flow when measurements are made. The timed automatic cycling of the system may be interrupted whenever desired, for manual operation. An analog output signal permits controlling an iodine generator.

  15. Food additives and Hymenolepis nana infection: an experimental study.

    PubMed

    El-Nouby, Kholoud A; Hamouda, Hala E; Abd El Azeem, Mona A; El-Ebiary, Ahmad A

    2009-12-01

    The effect of sodium benzoate (SB) on the pathogenesis of Hymenolepis nana (H. nana) and its neurological manifestations was studied in the present work. One hundred and thirty five mice were classified into three groups. GI: received SB alone. GII: received SB before & after infection with H. nana and GIII: infected with H. nana. All groups were subjected to parasitological, histopathological, immunohistochemical and biochemical assays. The results revealed a significant decrease in IL-4 serum level with a significant increase in gamma amino butyric acid (GABA) and decrease in zinc brain levels in GI, while GII showed non significant increase in IL-4 level that resulted in a highly significant increase in the mean number of cysticercoids and adult worms with delayed expulsion as compared to GIII. This was reflected on histopathological and immunohistochemical changes in the brain. Also, there was a highly significant increase in GABA and decrease in zinc brain levels in GII to the degree that induced behavioral changes. This emphasizes the possible synergistic effect of SB on the neurological manifestations of H. nana and could, in part, explain the increased incidence of behavioral changes in children exposed to high doses of SB and unfortunately have H. nana infection.

  16. Experimental Studies of Hydrogenation and Other Reactions on Surfaces Under Astrophysically Relevant Conditions

    NASA Technical Reports Server (NTRS)

    Vidali, Gianfranco

    1998-01-01

    The goal of our project is to study hydrogen recombination reactions on solid surfaces under conditions that are relevant in astrophysics. Laboratory experiments were conducted using low-flux, cold atomic H and D beams impinging on a sample kept under ultra high vacuum conditions. Realistic analogues of interstellar dust grains were used. Our results show that current models for hydrogen recombination reactions have to be modified to take into account the role of activated diffusion of H on surfaces even at low temperature.

  17. Laboratory studies of chemical and photochemical processes relevant to stratospheric ozone

    NASA Technical Reports Server (NTRS)

    Zahniser, Mark S.; Nelson, David D.; Worsnop, Douglas R.; Kolb, Charles E.

    1994-01-01

    The purpose of this project is to reduce the uncertainty in several key gas-phase kinetic processes which impact our understanding of stratospheric ozone. The main emphasis of this work is on measuring rate coefficients and product channels for reactions of HO(sub x) and NO(sub x) species in the temperature range 200 K to 240 K relevant to the lower stratosphere. Other areas of study have included infrared spectroscopic studies of the HO2 radical, measurements of OH radical reactions with alternative fluorocarbons, and determination of the vapor pressures of nitric acid hydrates under stratospheric conditions. The results of these studies will improve models of stratospheric ozone chemistry and predictions of perturbations due to human influences. In this annual report, we focus on our recent accomplishments in the quantitative spectroscopy of the HO2 radical. This report details the measurements of the broadening coefficients for the v(sub 2) vibrational band. Further measurements of the vapor pressures of nitric acid hydrates relevant to the polar stratospheric cloud formation indicate the importance of metastable crystalline phases of H2SO4, HNO3, and H2O. Large particles produced from these metastable phases may provide a removal mechanism for HNO3 in the polar stratosphere.

  18. Power to detect clinically relevant carry-over in a series of cross-over studies.

    PubMed

    Putt, Mary E

    2006-08-15

    The potential for carry-over effects is an important consideration in the design of any cross-over study, and can cause an investigator to abandon the design altogether. In cross-over studies, carry-over is the lingering effect of a treatment into the subsequent period. Carry-over effects are differences in the extent of the carry-over between the treatments under consideration. It is well known that the test for carry-over effects in individual studies has low power. Empirical evidence of carry-over effects, or the absence of carry-over effects, could be useful for investigators considering the design. Here we develop methods for expressing the power to detect carry-over as a function of the power to detect a clinically relevant treatment effect. Our results suggest that for two-treatment, two-period cross-over studies the power to detect clinically relevant carry-over effects is often less than 15 per cent, and the number of studies needed to differentiate this effect from the type I error rate of 10 per cent is prohibitive. For the three-treatment three-period cross-over design, the power to detect carry-over effects was larger than for the two-period study, but still approached the type I error rate in a number of cases. Unequivocal conclusions about the absence of carry-over effects based on collections of hypothesis tests appear unlikely. Similar findings are presented for bioequivalence studies. For bioequivalence studies, small carry-over effects (e.g. 12.5 per cent of the treatment effect) can seriously inflate the type I error rate, particularly when the power to detect equivalence is high.

  19. Isoflurane and desflurane at clinically relevant concentrations induce amyloid {beta}-peptide oligomerization: An NMR study

    SciTech Connect

    Mandal, Pravat K Fodale, Vincenzo

    2009-02-13

    Current understanding on Alzheimer's disease (AD) reveals that soluble amyloid {beta}-peptide (A{beta}) oligomeric formation plays an important role in AD pathophysiology. A potential role for several inhaled anesthetics in promoting A{beta} oligomer formation has been suggested. Using a nuclear magnetic resonance (NMR) study, we previously demonstrated that at a high concentration (higher than clinically relevant concentrations), the inhaled anesthetics halothane and isoflurane, interact with specific amino acid residues (G29, A30, and I31) and induce A{beta} oligomerization. The present study confirms this is true at a clinically relevant concentration. Isoflurane and desflurane induce A{beta} oligomerization by inducing chemical shift changes of the critical amino acid residues (G29, A30, and I31), reinforcing the evidence that perturbation of these three crucial residues indeed plays an important role in oligomerization. These findings support the emerging hypothesis that several commonly used inhaled anesthetics could be involved in neurodegeneration, as well as risk factor for accelerating the onset of AD.

  20. Unmanned Aircraft Systems for Studying Spatial Abundance of Ungulates: Relevance to Spatial Epidemiology

    PubMed Central

    Barasona, José A.; Mulero-Pázmány, Margarita; Acevedo, Pelayo; Negro, Juan J.; Torres, María J.; Gortázar, Christian; Vicente, Joaquín

    2014-01-01

    Complex ecological and epidemiological systems require multidisciplinary and innovative research. Low cost unmanned aircraft systems (UAS) can provide information on the spatial pattern of hosts’ distribution and abundance, which is crucial as regards modelling the determinants of disease transmission and persistence on a fine spatial scale. In this context we have studied the spatial epidemiology of tuberculosis (TB) in the ungulate community of Doñana National Park (South-western Spain) by modelling species host (red deer, fallow deer and cattle) abundance at fine spatial scale. The use of UAS high-resolution images has allowed us to collect data to model the environmental determinants of host abundance, and in a further step to evaluate their relationships with the spatial risk of TB throughout the ungulate community. We discuss the ecological, epidemiological and logistic conditions under which UAS may contribute to study the wildlife/livestock sanitary interface, where the spatial aggregation of hosts becomes crucial. These findings are relevant for planning and implementing research, fundamentally when managing disease in multi-host systems, and focusing on risky areas. Therefore, managers should prioritize the implementation of control strategies to reduce disease of conservation, economic and social relevance. PMID:25551673

  1. Study on the relevance of some of the description methods for plateau-honed surfaces

    NASA Astrophysics Data System (ADS)

    Yousfi, M.; Mezghani, S.; Demirci, I.; El Mansori, M.

    2014-01-01

    Much work has been undertaken in recent years into the determination of a complete parametric description of plateau-honed surfaces with the intention of making a link between the process conditions, the surface topography and the required functional performances. Different advanced techniques (plateau/valleys decomposition using the normalized Abbott-Firestone curve or morphological operators, multiscale decomposition using continuous wavelets transform, etc) were proposed and applied in different studies. This paper re-examines the current state of developments and addresses a discussion on the relevance of the different proposed parameters and characterization methods for plateau-honed surfaces by considering the control loop manufacturing-characterization-function. The relevance of appropriate characterization is demonstrated through two experimental studies. They consider the effect of the most plateau honing process variables (the abrasive grit size and abrasive indentation velocity in finish-honing and the plateau-honing stage duration and pressure) on cylinder liner surface textures and hydrodynamic friction of the ring-pack system.

  2. Laboratory Studies of Chemical and Photochemical Processes Relevant to Stratospheric Ozone

    NASA Technical Reports Server (NTRS)

    Zahniser, Mark S.; Nelson, David D.; Worsnop, Douglas R.; Kolb, Charles E.

    1996-01-01

    The purpose of this project is to reduce the uncertainty in several key gas-phase kinetic processes which impact our understanding of stratospheric ozone. The main emphasis of this work is on measuring rate coefficients and product channels for reactions of HOx and NOx species in the temperature range 200 K to 240 K relevant to the lower stratosphere. Other areas of study have included infrared spectroscopic studies of the HO radical, measurements of OH radical reactions with alternative fluorocarbons, and determination of the vapor pressures of nitric acid hydrates under stratospheric conditions. The results of these studies will improve models of stratospheric ozone chemistry and predictions of perturbations due to human influences.

  3. Chip-off-the-old-rock: the study of reservoir-relevant geological processes with real-rock micromodels.

    PubMed

    Song, Wen; de Haas, Thomas W; Fadaei, Hossein; Sinton, David

    2014-11-21

    We present a real-rock micromodel approach whereby microfluidic channels are fabricated in a naturally occurring mineral substrate. The method is applied to quantify calcite dissolution which is relevant to oil/gas recovery, CO2 sequestration, and wastewater disposal in carbonate formations - ubiquitous worldwide. The key advantage of this method is the inclusion of both the relevant substrate chemistry (not possible with conventional microfluidics) and real-time pore-scale resolution (not possible with core samples). Here, microchannels are etched into a natural calcite crystal and sealed with a glass slide. The approach is applied to study acidified brine flow through a single channel and a two-dimensional micromodel. The single-channel case conforms roughly to a 1-D analytical description, with crystal orientation influencing the local dissolution rate an additional 25%. The two-dimensional experiments show highly flow-directed dissolution and associated positive feedback wherein acid preferentially invades high conductivity flow paths, resulting in higher dissolution rates ('wormholing'). These experiments demonstrate and validate the approach of microfabricating fluid structures within natural minerals for transport and geochemical studies. More broadly, real-rock microfluidics open the door to a vast array of lab-on-a-chip opportunities in geology, reservoir engineering, and earth sciences.

  4. Effects of salt or cosolvent addition on solubility of a hydrophobic solute in water: Relevance to those on thermal stability of a protein

    NASA Astrophysics Data System (ADS)

    Murakami, Shota; Hayashi, Tomohiko; Kinoshita, Masahiro

    2017-02-01

    The solubility of a nonpolar solute in water is changed upon addition of a salt or cosolvent. Hereafter, "solvent" is formed by water molecules for pure water, by water molecules, cations, and anions for water-salt solution, and by water and cosolvent molecules for water-cosolvent solution. Decrease and increase in the solubility, respectively, are ascribed to enhancement and reduction of the hydrophobic effect. Plenty of experimental data are available for the change in solubility of argon or methane arising from the addition. We show that the integral equation theory combined with a rigid-body model, in which the solute and solvent particles are modeled as hard spheres with different diameters, can reproduce the data for the following items: salting out by an alkali halide and salting in by tetramethylammonium bromide, increase in solubility by a monohydric alcohol, and decrease in solubility by sucrose or urea. The orders of cation or anion species in terms of the power of decreasing the solubility can also be reproduced for alkali halides. With the rigid-body model, the analyses are focused on the roles of entropy originating from the translational displacement of solvent particles. It is argued by decomposing the solvation entropy of a nonpolar solute into physically insightful constituents that the solvent crowding in the bulk is a pivotal factor of the hydrophobic effect: When the solvent crowding in the bulk becomes more serious, the effect is strengthened, and when it becomes less serious, the effect is weakened. It is experimentally known that the thermal stability of a protein is also influenced by the salt or cosolvent addition. The additions which decrease and increase the solubility of a nonpolar solute, respectively, usually enhance and lower the thermal stability. This suggests that the enhanced or reduced hydrophobic effect is also a principal factor governing the stability change. However, urea decreases the solubility but lowers the stability

  5. Lab-on-a-brane: A novel physiologically relevant planar arterial model to study transendothelial transport

    NASA Astrophysics Data System (ADS)

    Budhwani, Karim Ismail

    The tremendous quality of life impact notwithstanding, cardiovascular diseases and Cancer add up to over US$ 700bn each year in financial costs alone. Aging and population growth are expected to further expand the problem space while drug research and development remain expensive. However, preclinical costs can be substantially mitigated by substituting animal models with in vitro devices that accurately model human cardiovascular transport. Here we present a novel physiologically relevant lab-on-a-brane that simulates in vivo pressure, flow, strain, and shear waveforms associated with normal and pathological conditions in large and small blood vessels for studying molecular transport across the endothelial monolayer. The device builds upon previously demonstrated integrated microfluidic loop design by: (a) introducing nanoscale pores in the substrate membrane to enable transmembrane molecular transport, (b) transforming the substrate membrane into a nanofibrous matrix for 3D smooth muscle cell (SMC) tissue culture, (c) integrating electrospinning fabrication methods, (d) engineering an invertible sandwich cell culture device architecture, and (e) devising a healthy co-culture mechanism for human arterial endothelial cell (HAEC) monolayer and multiple layers of human smooth muscle cells (HSMC) to accurately mimic arterial anatomy. Structural and mechanical characterization was conducted using confocal microscopy, SEM, stress/strain analysis, and infrared spectroscopy. Transport was characterized using FITC-Dextran hydraulic permeability protocol. Structure and transport characterization successfully demonstrate device viability as a physiologically relevant arterial mimic for testing transendothelial transport. Thus, our lab-on-a-brane provides a highly effective and efficient, yet considerably inexpensive, physiologically relevant alternative for pharmacokinetic evaluation; possibly reducing animals used in pre-clinical testing, clinical trials cost from false

  6. Using music to study the evolution of cognitive mechanisms relevant to language.

    PubMed

    Patel, Aniruddh D

    2017-02-01

    This article argues that music can be used in cross-species research to study the evolution of cognitive mechanisms relevant to spoken language. This is because music and language share certain cognitive processing mechanisms and because music offers specific advantages for cross-species research. Music has relatively simple building blocks (tones without semantic properties), yet these building blocks are combined into rich hierarchical structures that engage complex cognitive processing. I illustrate this point with regard to the processing of musical harmonic structure. Because the processing of musical harmonic structure has been shown to interact with linguistic syntactic processing in humans, it is of interest to know if other species can acquire implicit knowledge of harmonic structure through extended exposure to music during development (vs. through explicit training). I suggest that domestic dogs would be a good species to study in addressing this question.

  7. Thinking outside the (Voice) Box: A Case Study of Students' Perceptions of the Relevance of Anatomy to Speech Pathology

    ERIC Educational Resources Information Center

    Weir, Kristy A.

    2008-01-01

    Speech pathology students readily identify the importance of a sound understanding of anatomical structures central to their intended profession. In contrast, they often do not recognize the relevance of a broader understanding of structure and function. This study aimed to explore students' perceptions of the relevance of anatomy to speech…

  8. The Complexities of Culturally Relevant Pedagogy: A Case Study of Two Secondary Mathematics Teachers and Their ESOL Students

    ERIC Educational Resources Information Center

    Leonard, Jacqueline; Napp, Carolina; Adeleke, Shade

    2009-01-01

    Culturally relevant pedagogy is not well understood as an instructional strategy in the mathematics classroom. This study reveals the challenges two teachers faced when they implemented a pilot project with ninth and tenth grade ESOL students. The task they envisioned as culturally relevant did not capture their ESOL student's interests; rather,…

  9. Photoactivated disinfection of Streptococcus intermedius through dentin disc at clinically relevant intervals: an in vitro study.

    PubMed

    Bonstein, Tammy; Mikulski, Lynn M; Bush, Mary A; Bush, Peter J

    2010-10-01

    In this present study we have tested the impact of porfimer sodium (Photofrin, AXCAN PHARMA Inc., Quebec, Canada) photoactivated disinfection (PD) on cells of Streptococcus intermedius in suspension. In order to provide basic data to support future clinical studies of PD in dentistry the study used exposure to Quartz-tungsten-halogen (QTH) dental curing light for clinically relevant time periods to activate Photofrin and measured its effectiveness under a variety of conditions including activation through dentin hard tissue. S. intermedius was grown in planktonic suspension for 48h. Nine groups were formed: three control groups (1-3) and six experimental groups (4-9). Groups 4-6 tested the use of Photofrin treatment combined with QTH light at various intervals of irradiation (5, 15 and 60s). Groups 7-9 were similar to groups 4-6 with the exception that irradiation commenced through a dentin disc. Following treatment, bacteria were plated. Colony counts were measured following 72h incubation at 37 degrees C. Statistical analysis was carried out by one-way ANOVA at a 95% confidence level. A significant reduction in S. intermedius colony counts was observed for all experimental groups and one control group. The reduction in numbers of colonies in the experimental groups varied from 79.28 to 99.40% with an average of 94.61%. Reduction in viable bacterial cells indicated a strong relationship between power density and irradiation interval. When curing light energy density was lower due to the irradiation through the 1mm dentin disc, prolonged irradiation interval enhanced bacterial kill. In conclusion, where direct irradiation is not possible for PD treatment, irradiation through dentin may still be done successfully within a clinically relevant interval.

  10. Archives, accessibility, and advocacy: a case study of strategies for creating and maintaining relevance

    PubMed Central

    Welch, Jennifer M; Hoffius, Susan D; Fox, E. Brooke

    2011-01-01

    Question/Objective: How can a special collection maintain or increase its profile in its parent institution, when that parent institution emphasizes scientific and clinical learning? Setting/Context: The Waring Historical Library, Medical University of South Carolina (MUSC), preserves and promotes the history of health sciences at MUSC and in South Carolina. As a state entity, MUSC has suffered significant budget cuts for the past several years. In this climate, the Waring had to find ways to maintain relevance in the MUSC community. Methods: The Waring partnered with the MUSC College of Nursing to explore new ways to build institutional allies. By combining traditional archival administration with innovative uses of digital collections aimed at institutional promotion and outreach, the Waring's digital library became an advocacy tool that led to the Waring's enhanced value to its parent institution. Outcomes: The Waring Library is a resource for MUSC development and alumni relations. Tangible outcomes include additional funding from grants, increased staff, no loss of institutional funding, increased access to collections, increased accessions, cultivation of institutional allies for long-term support of the Waring, and development of a template for future partnerships. PMID:21243056

  11. New developments in measurements technology relevant to the studies of deep geological repositories in bedded salt

    SciTech Connect

    Mao, N.; Ramirez, A.L.

    1980-10-22

    This report presents new developments in measurement technology relevant to the studies of deep geological repositories for nuclear waste disposal during all phases of development, i.e., site selection, site characterization, construction, operation, and decommission. Emphasis has been placed on geophysics and geotechnics with special attention to those techniques applicable to bedded salt. The techniques are grouped into sections as follows: tectonic environment, state of stress, subsurface structures, fractures, stress changes, deformation, thermal properties, fluid transport properties, and other approaches. Several areas that merit further research and developments are identified. These areas are: in situ thermal measurement techniques, fracture detection and characterization, in situ stress measurements, and creep behavior. The available instrumentations should generally be improved to have better resolution and accuracy, enhanced instrument survivability, and reliability for extended time periods in a hostile environment.

  12. The Importance of Physiologically Relevant Cell Lines for Studying Virus–Host Interactions

    PubMed Central

    Hare, David; Collins, Susan; Cuddington, Breanne; Mossman, Karen

    2016-01-01

    Viruses interact intimately with the host cell at nearly every stage of replication, and the cell model that is chosen to study virus infection is critically important. Although primary cells reflect the phenotype of healthy cells in vivo better than cell lines, their limited lifespan makes experimental manipulation challenging. However, many tumor-derived and artificially immortalized cell lines have defects in induction of interferon-stimulated genes and other antiviral defenses. These defects can affect virus replication, especially when cells are infected at lower, more physiologically relevant, multiplicities of infection. Understanding the selective pressures and mechanisms underlying the loss of innate signaling pathways is helpful to choose immortalized cell lines without impaired antiviral defense. We describe the trials and tribulations we encountered while searching for an immortalized cell line with intact innate signaling, and how directed immortalization of primary cells avoids many of the pitfalls of spontaneous immortalization. PMID:27809273

  13. Laboratory Studies of Chemical and Photochemical Processes Relevant to Stratospheric Ozone

    NASA Technical Reports Server (NTRS)

    Villalta, Peter W.; Zahniser, Mark S.; Nelson, David D.; Kolb, Charles E.

    1997-01-01

    The purpose of this project is to reduce the uncertainty in several key gas-phase kinetic processes which impact our understanding of stratospheric ozone. The main emphasis of this work is on measuring rate coefficients and product channels for reactions of HO(x) and NO(x) species in the temperature range 200 K to 240 K relevant to the lower stratosphere. The results of these studies will improve models of stratospheric ozone chemistry and predictions of perturbations due to human influences. The second year's effort has focussed the design and construction of the proposed high pressure flow reactor on three separate areas: (1) the construction of the high pressure flow reactor; (2) characterization of the turbulent flow profile; and (3) demonstration of the instrument by measuring HO2 + NO2 and HO2 + NO reaction rate coefficients.

  14. Breast Cancer Education for Navajo Women: a Pilot Study Evaluating a Culturally Relevant Video

    PubMed Central

    Teufel-Shone, Nicolette I.; Baldwin, Julie A.; Sandoval, Nellie; Robinson, Frances

    2010-01-01

    This pilot study evaluated a culturally specific video designed to teach Navajo women about breast cancer treatment options. Fourteen Navajo women diagnosed with breast cancer and 26 healthcare providers participated in a mixed-method evaluation that documented their perceptions immediately and 6 months after viewing the video. After initial viewing, women reported reduced anxiety about treatment and interest in support groups. Six months later, women said the video prompted them to seek more information from printed sources and their provider. Younger Navajo women who were 44 to 51 years old were more likely to attend support groups than women who were 55–67 years. Providers corroborated the positive effects of the video. The providers believed the video encouraged patients to seek information about breast cancer and to ask questions about treatment plans and side effects. A culturally relevant video for Navajo women can be an effective teaching tool and can enhance patient–provider communication. PMID:20111913

  15. Density functional theory study of the effects of alloying additions on sulfur adsorption on nickel surfaces

    NASA Astrophysics Data System (ADS)

    Malyi, Oleksandr I.; Chen, Zhong; Kulish, Vadym V.; Bai, Kewu; Wu, Ping

    2013-01-01

    Reactions of hydrogen sulfide (H2S) with Nickel/Ytrria-doped zirconia (Ni/YDZ) anode materials might cause degradation of the performance of solid oxide fuel cells when S containing fuels are used. In this paper, we employ density functional theory to investigate S adsorption on metal (M)-doped and undoped Ni(0 0 1) and Ni(1 1 1) surfaces. Based on the performed calculations, we analyze the effects of 12 alloying additions (Ag, Au, Al, Bi, Cd, Co, Cu, Fe, Sn, Sb, V, and Zn) on the temperature of transition between clean (S atoms do not adsorb on the surfaces) and contaminated (S atoms can adsorb on the surfaces spontaneously) M-doped Ni surfaces for different concentrations of H2S in the fuel. Predicted results are consistent with many experimental studies relevant to S poisoning of both Ni/YDZ and M-doped Ni/YDZ anode materials. This study is important to understand S poisoning phenomena and to develop new S tolerant anode materials.

  16. Guidance on assessing the methodological and reporting quality of toxicologically relevant studies: A scoping review.

    PubMed

    Samuel, Gbeminiyi O; Hoffmann, Sebastian; Wright, Robert A; Lalu, Manoj Mathew; Patlewicz, Grace; Becker, Richard A; DeGeorge, George L; Fergusson, Dean; Hartung, Thomas; Lewis, R Jeffrey; Stephens, Martin L

    2016-01-01

    Assessments of methodological and reporting quality are critical to adequately judging the credibility of a study's conclusions and to gauging its potential reproducibility. To aid those seeking to assess the methodological or reporting quality of studies relevant to toxicology, we conducted a scoping review of the available guidance with respect to four types of studies: in vivo and in vitro, (quantitative) structure-activity relationships ([Q]SARs), physico-chemical, and human observational studies. Our aims were to identify the available guidance in this diverse literature, briefly summarize each document, and distill the common elements of these documents for each study type. In general, we found considerable guidance for in vivo and human studies, but only one paper addressed in vitro studies exclusively. The guidance for (Q)SAR studies and physico-chemical studies was scant but authoritative. There was substantial overlap across guidance documents in the proposed criteria for both methodological and reporting quality. Some guidance documents address toxicology research directly, whereas others address preclinical research generally or clinical research and therefore may not be fully applicable to the toxicology context without some translation. Another challenge is the degree to which assessments of methodological quality in toxicology should focus on risk of bias - as in clinical medicine and healthcare - or be broadened to include other quality measures, such as confirming the identity of test substances prior to exposure. Our review is intended primarily for those in toxicology and risk assessment seeking an entry point into the extensive and diverse literature on methodological and reporting quality applicable to their work.

  17. SMART-1 highlights and relevant studies on early bombardment and geological processes on rocky planets

    NASA Astrophysics Data System (ADS)

    Foing, B. H.; Racca, G. D.; Josset, J. L.; Koschny, D.; Frew, D.; Almeida, M.; Zender, J.; Heather, D.; Peters, S.; Marini, A.; Stagnaro, L.; Beauvivre, S.; Grande, M.; Kellett, B.; Huovelin, J.; Nathues, A.; Mall, U.; Ehrenfreund, P.; McCannon, P.

    2008-08-01

    We present results from SMART-1 science and technology payload, in the context of the Nobel symposium on 'Physics of Planetary Systems'. SMART-1 is Europe' first lunar mission (Foing et al 2000 LPSC XXXI Abstract #1677 (CDROM); Foing et al 2001 Earth, Moon Planets 85 86 523 31 Marini et al 2002 Adv. Space Res. 30 1895 900 Racca et al 2001 Earth Moon Planets 85 86 379 95, Racca et al 2002 Planet Space Sci. 50 1323 37) demonstrating technologies for future science and exploration missions, and providing advances in our understanding of lunar origin and evolution, and general planetary questions. The mission also contributes a step in developing an international program of lunar exploration. The spacecraft, launched on 27 September 2003 as an Ariane 5 Auxiliary passenger to geostationary transfer orbit (GTO), performed a 14-month long cruise using a tiny thrust of electric propulsion alone, reached lunar capture in November 2004, and lunar science orbit in March 2005. SMART-1 carried 7 hardware experiments (Foing et al 2003 Adv. Space Res. 31 2323, Foing et al 2005 LPI/LPSC XXXVI 2404 (CDROM)) performing 10 investigations, including 3 remote-sensing instruments, used during the cruise, the mission' nominal six-months and one-year extension in lunar science orbit. Three remote sensing instruments, D-CIXS, SIR and AMIE, have returned data that are relevant to a broad range of lunar studies. The mission provided regional and global x-ray measurements of the Moon, global high-spectral resolution NIR spectrometry, high spatial resolution colour imaging of selected regions. The South Pole-Aitken Basin (SPA) and other impact basins have been prime targets for studies using the SMART-1 suite of instruments. Combined, these should aid a large number of science studies, from bulk crustal composition and theories of lunar origin/evolution, the global and local crustal composition, to the search for cold traps at the lunar poles and the mapping of potential lunar resources. We

  18. A Pilot Study of Ion - Molecule Reactions at Temperatures Relevant to the Atmosphere of Titan

    NASA Astrophysics Data System (ADS)

    Zymak, Illia; Žabka, Ján; Polášek, Miroslav; Španěl, Patrik; Smith, David

    2016-11-01

    Reliable theoretical models of the chemical kinetics of the ionosphere of Saturn's moon, Titan, is highly dependent on the precision of the rates of the reactions of ambient ions with hydrocarbon molecules at relevant temperatures. A Variable Temperature Selected Ions Flow Tube technique, which has been developed primarily to study these reactions at temperatures within the range of 200-330 K, is briefly described. The flow tube temperature regulation system and the thermalisation of ions are also discussed. Preliminary studies of two reactions have been carried out to check the reliability and efficacy of kinetics measurements: (i) Rate constants of the reaction of CH3 + ions with molecular oxygen were measured at different temperatures, which indicate values in agreement with previous ion cyclotron resonance measurements ostensibly made at 300 K. (ii) Formation of CH3 + ions in the reaction of N2 + ions with CH4 molecules were studied at temperatures within the range 240-310 K which showed a small but statistically significant decrease of the ratio of product CH3 + ions to reactant N2 + ions with reaction temperature.

  19. A Pilot Study of Ion - Molecule Reactions at Temperatures Relevant to the Atmosphere of Titan.

    PubMed

    Zymak, Illia; Žabka, Ján; Polášek, Miroslav; Španěl, Patrik; Smith, David

    2016-11-01

    Reliable theoretical models of the chemical kinetics of the ionosphere of Saturn's moon, Titan, is highly dependent on the precision of the rates of the reactions of ambient ions with hydrocarbon molecules at relevant temperatures. A Variable Temperature Selected Ions Flow Tube technique, which has been developed primarily to study these reactions at temperatures within the range of 200-330 K, is briefly described. The flow tube temperature regulation system and the thermalisation of ions are also discussed. Preliminary studies of two reactions have been carried out to check the reliability and efficacy of kinetics measurements: (i) Rate constants of the reaction of CH3(+) ions with molecular oxygen were measured at different temperatures, which indicate values in agreement with previous ion cyclotron resonance measurements ostensibly made at 300 K. (ii) Formation of CH3(+) ions in the reaction of N2(+) ions with CH4 molecules were studied at temperatures within the range 240-310 K which showed a small but statistically significant decrease of the ratio of product CH3(+) ions to reactant N2(+) ions with reaction temperature.

  20. Thinking outside the (voice) box: a case study of students' perceptions of the relevance of anatomy to speech pathology.

    PubMed

    Weir, Kristy A

    2008-01-01

    Speech pathology students readily identify the importance of a sound understanding of anatomical structures central to their intended profession. In contrast, they often do not recognize the relevance of a broader understanding of structure and function. This study aimed to explore students' perceptions of the relevance of anatomy to speech pathology. The effect of two learning activities on students' perceptions was also evaluated. First, a written assignment required students to illustrate the relevance of anatomy to speech pathology by using an example selected from one of the four alternative structures. The second approach was the introduction of brief "scenarios" with directed questions into the practical class. The effects of these activities were assessed via two surveys designed to evaluate students' perceptions of the relevance of anatomy before and during the course experience. A focus group was conducted to clarify and extend discussion of issues arising from the survey data. The results showed that the students perceived some course material as irrelevant to speech pathology. The importance of relevance to the students' "state" motivation was well supported by the data. Although the students believed that the learning activities helped their understanding of the relevance of anatomy, some structures were considered less relevant at the end of the course. It is likely that the perceived amount of content and surface approach to learning may have prevented students from "thinking outside the box" regarding which anatomical structures are relevant to the profession.

  1. A preliminary assessment of geologic framework and sediment thickness studies relevant to prospective US submission on extended continental shelf

    USGS Publications Warehouse

    Hutchinson, Deborah R.; Childs, Jonathan R.; Hammar-Klose, Erika; Dadisman, Shawn; Edgar, N. Terrence; Barth, Ginger A.

    2004-01-01

    Under the provisions of Articles 76 and 77 of the United Nations Convention on the Law of the Sea (UNCLOS), coastal States have sovereign rights over the continental shelf territory beyond 200-nautical mile (nm) from the baseline from which the territorial sea is measured if certain conditions are met regarding the geologic and physiographic character of the legal continental shelf as defined in those articles. These claims to an extended continental shelf must be supported by relevant bathymetric, geophysical and geological data according to guidelines established by the Commission on the Limits of the Continental Shelf (CLCS, 1999). In anticipation of the United States becoming party to UNCLOS, Congress in 2001 directed the Joint Hydrographic Center/Center for Coastal and Ocean Mapping at the University of New Hampshire to conduct a study to evaluate data relevant to establishing the outer limit of the juridical continental shelf beyond 200 nm and to recommend what additional data might be needed to substantiate such an outer limit (Mayer and others, 2002). The resulting report produced an impressive and sophisticated GIS database of data sources. Because of the short time allowed to complete the report, all seismic reflection data were classified together; the authors therefore recommended that USGS perform additional analysis on seismic and related data holdings. The results of this additional analysis are the substance of this report, including the status of geologic framework, sediment isopach research, and resource potential in the eight regions1 identified by Mayer and others (2002) where analysis of seismic data might be crucial for establishing an outer limit . Seismic reflection and refraction data are essential in determining sediment thickness, one of the criteria used in establishing the outer limits of the juridical continental shelf. Accordingly, the initial task has been to inventory public-domain seismic data sources, primarily those regionally

  2. Identifying stakeholder-relevant climate change impacts: a case study in the Yakima River Basin, Washington, USA

    USGS Publications Warehouse

    Jenni, K.; Graves, D.; Hardiman, Jill M.; Hatten, James R.; Mastin, Mark C.; Mesa, Matthew G.; Montag, J.; Nieman, Timothy; Voss, Frank D.; Maule, Alec G.

    2014-01-01

    Designing climate-related research so that study results will be useful to natural resource managers is a unique challenge. While decision makers increasingly recognize the need to consider climate change in their resource management plans, and climate scientists recognize the importance of providing locally-relevant climate data and projections, there often remains a gap between management needs and the information that is available or is being collected. We used decision analysis concepts to bring decision-maker and stakeholder perspectives into the applied research planning process. In 2009 we initiated a series of studies on the impacts of climate change in the Yakima River Basin (YRB) with a four-day stakeholder workshop, bringing together managers, stakeholders, and scientists to develop an integrated conceptual model of climate change and climate change impacts in the YRB. The conceptual model development highlighted areas of uncertainty that limit the understanding of the potential impacts of climate change and decision alternatives by those who will be most directly affected by those changes, and pointed to areas where additional study and engagement of stakeholders would be beneficial. The workshop and resulting conceptual model highlighted the importance of numerous different outcomes to stakeholders in the basin, including social and economic outcomes that go beyond the physical and biological outcomes typically reported in climate impacts studies. Subsequent studies addressed several of those areas of uncertainty, including changes in water temperatures, habitat quality, and bioenergetics of salmonid populations.

  3. Attentional demand and processing of relevant visual information during simulated driving: a MEG study.

    PubMed

    Fort, Alexandra; Martin, Robert; Jacquet-Andrieu, Armelle; Combe-Pangaud, Chantal; Foliot, Gérald; Daligault, Sébastien; Delpuech, Claude

    2010-12-02

    It is a well-known fact that attention is crucial for driving a car. This innovative study aims to assess the impact of attentional workload modulation on cerebral activity during a simulated driving task using magnetoencephalography (MEG). A car simulator equipped with a steering wheel, turn indicators, an accelerator and a brake pedal has been specifically designed to be used with MEG. Attentional demand has been modulated using a radio broadcast. During half of the driving scenarios, subjects could ignore the broadcast (simple task, ST) and during the other half, they had to actively listen to it in order to answer 3 questions (dual task, DT). Evoked magnetic responses were computed in both conditions separately for two visual stimuli of interest: traffic lights (from green to amber) and direction signs (arrows to the right or to the left) shown on boards. The cortical sources of these activities have been estimated using a minimum-norm current estimates modeling technique. Results show the activation of a large distributed network similar in ST and DT and similar for both the traffic lights and the direction signs. This network mainly involves sensory visual areas as well as parietal and frontal regions known to play a role in selective attention and motor areas. The increase of attentional demand affects the neuronal processing of relevant visual information for driving, as early as the perceptual stage. By demonstrating the feasibility of recording MEG activity during an interactive simulated driving task, this study opens new possibilities for investigating issues regarding drivers' activity.

  4. The bile duct ligated rat: A relevant model to study muscle mass loss in cirrhosis.

    PubMed

    Bosoi, Cristina R; Oliveira, Mariana M; Ochoa-Sanchez, Rafael; Tremblay, Mélanie; Ten Have, Gabriella A; Deutz, Nicolaas E; Rose, Christopher F; Bemeur, Chantal

    2017-04-01

    Muscle mass loss and hepatic encephalopathy (complex neuropsychiatric disorder) are serious complications of chronic liver disease (cirrhosis) which impact negatively on clinical outcome and quality of life and increase mortality. Liver disease leads to hyperammonemia and ammonia toxicity is believed to play a major role in the pathogenesis of hepatic encephalopathy. However, the effects of ammonia are not brain-specific and therefore may also affect other organs and tissues including muscle. The precise pathophysiological mechanisms underlying muscle wasting in chronic liver disease remains to be elucidated. In the present study, we characterized body composition as well as muscle protein synthesis in cirrhotic rats with hepatic encephalopathy using the 6-week bile duct ligation (BDL) model which recapitulates the main features of cirrhosis. Compared to sham-operated control animals, BDL rats display significant decreased gain in body weight, altered body composition, decreased gastrocnemius muscle mass and circumference as well as altered muscle morphology. Muscle protein synthesis was also significantly reduced in BDL rats compared to control animals. These findings demonstrate that the 6-week BDL experimental rat is a relevant model to study liver disease-induced muscle mass loss.

  5. Relevance of aquatic environments for hominins: a case study from Trinil (Java, Indonesia).

    PubMed

    Joordens, J C A; Wesselingh, F P; de Vos, J; Vonhof, H B; Kroon, D

    2009-12-01

    Knowledge about dietary niche is key to understanding hominin evolution, since diet influences body proportions, brain size, cognition, and habitat preference. In this study we provide ecological context for the current debate on modernity (or not) of aquatic resource exploitation by hominins. We use the Homo erectus site of Trinil as a case study to investigate how research questions on possible dietary relevance of aquatic environments can be addressed. Faunal and geochemical analysis of aquatic fossils from Trinil Hauptknochenschicht (HK) fauna demonstrate that Trinil at approximately 1.5Ma contained near-coastal rivers, lakes, swamp forests, lagoons, and marshes with minor marine influence, laterally grading into grasslands. Trinil HK environments yielded at least eleven edible mollusc species and four edible fish species that could be procured with no or minimal technology. We demonstrate that, from an ecological point of view, the default assumption should be that omnivorous hominins in coastal habitats with catchable aquatic fauna could have consumed aquatic resources. The hypothesis of aquatic exploitation can be tested with taphonomic analysis of aquatic fossils associated with hominin fossils. We show that midden-like characteristics of large bivalve shell assemblages containing Pseudodon and Elongaria from Trinil HK indicate deliberate collection by a selective agent, possibly hominin.

  6. Selected, annotated bibliography of studies relevant to the isolation of nuclear wastes. [705 references

    SciTech Connect

    Hyder, L.K.; Fore, C.S.; Vaughan, N.D.; Faust, R.A.

    1980-09-01

    This annotated bibliography of 705 references represents the first in a series to be published by the Ecological Sciences Information Center containing scientific, technical, economic, and regulatory information relevant to nuclear waste isolation. Most references discuss deep geologic disposal, with fewer studies of deep seabed disposal; space disposal is also included. The publication covers both domestic and foreign literature for the period 1954 to 1980. Major chapters selected are Chemical and Physical Aspects; Container Design and Performance; Disposal Site; Envirnmental Transport; General Studies and Reviews; Geology, Hydrology and Site Resources; Regulatory and Economic Aspects; Repository Design and Engineering; Transportation Technology; Waste Production; and Waste Treatment. Specialized data fields have been incorporated to improve the ease and accuracy of locating pertinent references. Specific radionuclides for which data are presented are listed in the Measured Radionuclides field, and specific parameters which affect the migration of these radionuclides are presented in the Measured Parameters field. The references within each chapter are arranged alphabetically by leading author, corporate affiliation, or title of the document. When the author is not given, the corporate affiliation appears first. If these two levels of authorship are not given, the title of the document is used as the identifying level. Indexes are provided for author(s), keywords, subject category, title, geographic location, measured parameters, measured radionuclides, and publication description.

  7. A Study of Ablation-Flowfield Coupling Relevant to the Orion Heatshield

    NASA Technical Reports Server (NTRS)

    Johnston, Christopher O.; Gnoffo, Peter A.; Mazaheri, Alireza

    2009-01-01

    The coupled interaction between an ablating surface and the surrounding aerothermal environment is studied. An equilibrium ablation model is coupled to the LAURA flowfield solver, which allows the char ablation rate (m-dot(sub c)) to be computed as part of the flowfield solution. The wall temperature (T(sub w)) and pyrolysis ablation rate (m-dot(sub g)) may be specified by the user, obtained from the steady-state ablation approximation, or computed from a a material response code. A 32 species thermochemical nonequilibrium flowfield model is applied, which permits the treatment of C, H, O, N, and Si containing species. Coupled ablation cases relevant to the Orion heatshield are studied. These consist of diffusion-limited oxidation cases with Avcoat as the ablation material. The m-dot(sub c) values predicted from the developed coupled ablation analysis were compared with those obtained from a typical uncoupled ablation analysis. The coupled results were found to be as much as 50% greater than the uncoupled values. This is shown to be a result of the cumulative effect of the two fundamental approximations inherent in the uncoupled analysis.

  8. Laboratory Studies of Phosphine Chemistry Relevant to the Jovian and Saturnian Atmospheres

    NASA Astrophysics Data System (ADS)

    Liu, Yingdi; Matsiev, Daniel; Robertson, Robert; White, Jason

    2016-10-01

    The photochemistry of phosphine (PH3) in the tropospheres of Saturn and Jupiter is initiated by ultraviolet (UV) radiation and then follows a cascade of chemical reactions that result in P-H hydrides as well as the condensed chromophore red phosphorus (P4). A key intermediate in this pathway is diphosphine (P2H4). The rate constants for the photodissociation of phosphine into initial phosphino radicals and consequently into formation of diphosphine are currently unavailable, limiting their applicability to observational measurements. The condensation of diphosphine to ice in the cold tropospheres is also poorly understood due to the difficulties in synthesizing, handling, and analyzing the compound.Our presentation will describe two experiments at SRI International to produce rate constants for the photochemistry initiated by UV light interacting with phosphine and diphosphine and properties related to the condensed phases of these species. One study seeks to produce property values for application in photochemical and cloud/haze models. Specifically, we extend the measured vapor pressure curve for diphosphine to temperatures relevant to temperatures of Saturn and Jupiter. A sophisticated vapor pressure cell has been constructed and tested and is coupled to a Fourier transform infrared (FTIR) and mass spectrometer for high-fidelity species diagnostics. A companion study investigates phosphine photochemistry to measure the rate constants of key intermediate species related to the loss of PH3 and the formation of P2H4. The experiments employ laser photolysis at 193 nm followed by time-resolved mid-IR laser-based species detection of reactants, and the products provide basic chemical kinetic data useful for interpreting phosphine photochemistry in planetary atmospheres.These two studies are intended to supply basic physical measurements to aid in the interpretation of outer planet atmospheric observations. For both studies, we will present our latest laboratory

  9. Laboratory Studies of Ethane Ice Relevant to Outer Solar System Surfaces

    NASA Astrophysics Data System (ADS)

    Moore, Marla H.; Hudson, R. L.; Raines, L.

    2009-09-01

    Oort Cloud comets, as well as TNOs Makemake (2005 FY9), Quaoar, and Pluto, are known to contain ethane. However, even though this molecule is found on several outer Solar System objects relatively little information is available about its amorphous and crystalline phases. In new experiments, we have prepared ethane ices at temperatures applicable to the outer Solar System, and have heated and ion-irradiated these ices to study phase changes and ethane's radiation chemistry using mid-IR spectroscopy (2.2 - 16.6 microns). Included in our work is the meta-stable phase that exists at 35 - 55 K. These results, including newly obtained optical constants, are relevant to ground-based observational campaigns, the New Horizons mission, and supporting laboratory work. An improved understanding of solid-phase ethane may contribute to future searches for this and other hydrocarbons in the outer Solar System. This work was funded by NASA's Planetary Geology and Geophysics, Planetary Atmospheres, and Outer Planets programs. LR was supported by a summer research internship at the NASA Astrobiology Institute's Goddard Center for Astrobiology.

  10. Suicide in the Greek penal system and the problem of various limitations in relevant studies.

    PubMed

    Themeli, Olga

    2006-01-01

    Suicides in prison are not merely self-destructive acts or a "cry for help." They reflect the inherent need for freedom and the repercussions of imprisonment. SPACE statistics on suicides in prison reveal a rate above 10 per 10,000 in 10 European countries, 4 of which have a rate above 20. Greek data do not appear in all SPACE statistics. This fact has stimulated the present paper. Unpublished data obtained from the Greek Ministry of Justice reveal that Greece belongs to the group of countries with a rate below 10 in 1995 (the year of SPACE statistics). However, the suicide rates fluctuated widely in Greece from a low rate of 3.2 per 10,000 prisoners (convicted, on remand, or hospitalized) in 1982 to the incredibly high rate of nearly 40 in the year 1979 (11 suicides, 10 of which occurred in prison hospitals). A review of the literature indicates that various limitations mentioned in relevant studies lie in the unreliability of data (doubts about the validity of official statistics, missing data in archives, missing files on the victims, suicide in juvenile institutions not always recorded separately, etc.). The research emphasizes the importance of improving suicide statistics (recording, clearing up the incidents of deaths that are recorded without specification of cause, etc.) in order to plan and enforce suicide prevention and intervention strategies that seem to "work" in a particular milieu and are not debatable (e.g., the use of "suicide proof" cells).

  11. Food additive carrageenan: Part II: A critical review of carrageenan in vivo safety studies.

    PubMed

    Weiner, Myra L

    2014-03-01

    Carrageenan (CGN) is a seaweed-derived high molecular weight (Mw) hydrocolloid, primarily used as a stabilizer and thickener in food. The safety of CGN regarding its use in food is reviewed. Based on experimental studies in animals, ingested CGN is excreted quantitatively in the feces. Studies have shown that CGN is not significantly degraded by low gastric pH or microflora in the gastrointestinal (GI) tract. Due to its Mw, structure and its stability when bound to protein, CGN is not significantly absorbed or metabolized. CGN also does not significantly affect the absorption of nutrients. Subchronic and chronic feeding studies in rodents indicate that CGN at doses up to 5% in the diet does not induce any toxicological effects other than soft stools or diarrhea, which are a common effect for non-digestible high molecular weight compounds. Review of several studies from numerous species indicates that food grade CGN does not produce intestinal ulceration at doses up to 5% in the diet. Effects of CGN on the immune system following parenteral administration are well known, but not relevant to food additive uses. The majority of the studies evaluating the immunotoxicity potential were conducted with CGN administered in drinking water or by oral gavage where CGN exists in a random, open structured molecular conformation, particularly the lambda form; hence, it has more exposure to the intestinal mucosa than when bound to protein in food. Based on the many animal subchronic and chronic toxicity studies, CGN has not been found to affect the immune system, as judged by lack of effects on organ histopathology, clinical chemistry, hematology, normal health, and the lack of target organ toxicities. In these studies, animals consumed CGN at orders of magnitude above levels of CGN in the human diet: ≥1000 mg/kg/d in animals compared to 18-40 mg/kg/d estimated in the human diet. Dietary CGN has been shown to lack carcinogenic, tumor promoter, genotoxic, developmental, and

  12. Perceptions of the relevance of mathematics and science: An Australian study

    NASA Astrophysics Data System (ADS)

    Jones, Jennifer; Young, Deidra J.

    1995-03-01

    This study examined students from schools mostly in Sydney and Wollongong (New South Wales, Australia). While the private girls' school used in this survey has had a very good record of girls staying on in physics, some of the public schools surveyed have had very low retention rates (and not only in the science and mathematics areas). This paper attempts to describe student differences in perceptions and attitudes and how these are related to gender and type of school. Additionally, students' perceived reasons for not performing well in mathematics and science were investigated.

  13. Social Studies Pedagogy for Latino/a Newcomer Youth: Toward a Theory of Culturally and Linguistically Relevant Citizenship Education

    ERIC Educational Resources Information Center

    Jaffee, Ashley Taylor

    2016-01-01

    This study examines how teachers in 4 urban newcomer high schools conceptualized and implemented social studies education for Latino/a newcomer youth through an emerging framework of culturally and linguistically relevant citizenship education. Through a multi-site, collective case study design, the perspectives and decision making of social…

  14. Relevancy 101

    NASA Technical Reports Server (NTRS)

    Lynnes, Chris; Newman, Doug

    2016-01-01

    Where we present an overview on why relevancy is a problem, how important it is and how we can improve it. The topic of relevancy is becoming increasingly important in earth data discovery as our audience is tuned to the accuracy of standard search engines like Google.

  15. Remote-Raman spectroscopic study of minerals under supercritical CO2 relevant to Venus exploration.

    PubMed

    Sharma, Shiv K; Misra, Anupam K; Clegg, Samuel M; Barefield, James E; Wiens, Roger C; Acosta, Tayro E; Bates, David E

    2011-10-01

    The authors have utilized a recently developed compact Raman spectrometer equipped with an 85 mm focal length (f/1.8) Nikon camera lens and a custom mini-ICCD detector at the University of Hawaii for measuring remote Raman spectra of minerals under supercritical CO(2) (Venus chamber, ∼102 atm pressure and 423 K) excited with a pulsed 532 nm laser beam of 6 mJ/pulse and 10 Hz. These experiments demonstrate that by focusing a frequency-doubled 532 nm Nd:YAG pulsed laser beam with a 10× beam expander to a 1mm spot on minerals located at 2m inside a Venus chamber, it is possible to measure the remote Raman spectra of anhydrous sulfates, carbonates, and silicate minerals relevant to Venus exploration during daytime or nighttime with 10s integration time. The remote Raman spectra of gypsum, anhydrite, barite, dolomite and siderite contain fingerprint Raman lines along with the Fermi resonance doublet of CO(2). Raman spectra of gypsum revealed dehydration of the mineral with time under supercritical CO(2) at 423 K. Fingerprint Raman lines of olivine, diopside, wollastonite and α-quartz can easily be identified in the spectra of these respective minerals under supercritical CO(2). The results of the present study show that time-resolved remote Raman spectroscopy with a compact Raman spectrometer of moderate resolution equipped with a gated intensified CCD detector and low power laser source could be a potential tool for exploring Venus surface mineralogy both during daytime and nighttime from a lander.

  16. Ecological relevance of biomarkers in monitoring studies of macro-invertebrates and fish in Mediterranean rivers.

    PubMed

    Colin, Nicole; Porte, Cinta; Fernandes, Denise; Barata, Carlos; Padrós, Francesc; Carrassón, Maite; Monroy, Mario; Cano-Rocabayera, Oriol; de Sostoa, Adolfo; Piña, Benjamín; Maceda-Veiga, Alberto

    2016-01-01

    Mediterranean rivers are probably one of the most singular and endangered ecosystems worldwide due to the presence of many endemic species and a long history of anthropogenic impacts. Besides a conservation value per se, biodiversity is related to the services that ecosystems provide to society and the ability of these to cope with stressors, including climate change. Using macro-invertebrates and fish as sentinel organisms, this overview presents a synthesis of the state of the art in the application of biomarkers (stress and enzymatic responses, endocrine disruptors, trophic tracers, energy and bile metabolites, genotoxic indicators, histopathological and behavioural alterations, and genetic and cutting edge omic markers) to determine the causes and effects of anthropogenic stressors on the biodiversity of European Mediterranean rivers. We also discuss how a careful selection of sentinel species according to their ecological traits and the food-web structure of Mediterranean rivers could increase the ecological relevance of biomarker responses. Further, we provide suggestions to better harmonise ecological realism with experimental design in biomarker studies, including statistical analyses, which may also deliver a more comprehensible message to managers and policy makers. By keeping on the safe side the health status of populations of multiple-species in a community, we advocate to increase the resilience of fluvial ecosystems to face present and forecasted stressors. In conclusion, this review provides evidence that multi-biomarker approaches detect early signs of impairment in populations, and supports their incorporation in the standardised procedures of the Water Frame Work Directive to better appraise the status of European water bodies.

  17. Study of wood plastic composite in the presence of nitrogen containing additives

    NASA Astrophysics Data System (ADS)

    Ali, K. M. Idriss; Khan, Mubarak A.; Husain, M. M.

    1994-10-01

    Effect of nitrogen-containing additives in the study of wood plastic composites of MMA with simul and mango wood of Bangladesh has been investigated. Nine different additives were used and the additives containing carboamide group induce the highest tensile strength to the composite.

  18. Student perception of relevance of biology content to everyday life: A study in higher education biology courses

    NASA Astrophysics Data System (ADS)

    Himschoot, Agnes Rose

    The purpose of this mixed method case study was to examine the effects of methods of instruction on students' perception of relevance in higher education non-biology majors' courses. Nearly ninety percent of all students in a liberal arts college are required to take a general biology course. It is proposed that for many of those students, this is the last science course they will take for life. General biology courses are suspected of discouraging student interest in biology with large enrollment, didactic instruction, covering a huge amount of content in one semester, and are charged with promoting student disengagement with biology by the end of the course. Previous research has been aimed at increasing student motivation and interest in biology as measured by surveys and test results. Various methods of instruction have been tested and show evidence of improved learning gains. This study focused on students' perception of relevance of biology content to everyday life and the methods of instruction that increase it. A quantitative survey was administered to assess perception of relevance pre and post instruction over three topics typically taught in a general biology course. A second quantitative survey of student experiences during instruction was administered to identify methods of instruction used in the course lecture and lab. While perception of relevance dropped in the study, qualitative focus groups provided insight into the surprising results by identifying topics that are more relevant than the ones chosen for the study, conveying the affects of the instructor's personal and instructional skills on student engagement, explanation of how active engagement during instruction promotes understanding of relevance, the roll of laboratory in promoting students' understanding of relevance as well as identifying external factors that affect student engagement. The study also investigated the extent to which gender affected changes in students' perception of

  19. A Film Evaluation Checklist to Describe Instructionally Relevant Film Characteristics: A Rater Reliability Study.

    ERIC Educational Resources Information Center

    Burke, Nancy E.; And Others

    A Film Evaluation Checklist, developed at the National Technical Institute for the Deaf, describes instructionally relevant film characteristics. The instrument is organized in terms of structural characteristics of the medium, modes of concept emphasis using film techniques, and organization of instructional material. Raters independently rated…

  20. Perceptions on Social Networking: A Study on Their Operational Relevance for the Navy

    DTIC Science & Technology

    2010-03-01

    in a shared network. VIRT would essentially isolate the “ wheat from the chaff” and present the warfighter with only the relevant tactical...Socialnomics: How social media transforms the way we live and do Business. Hoboken, NJ: Wiley. Rust , S. M. (2006). Collaborative network evolution

  1. Systematically Identifying Relevant Research: Case Study on Child Protection Social Workers' Resilience

    ERIC Educational Resources Information Center

    McFadden, Paula; Taylor, Brian J.; Campbell, Anne; McQuilkin, Janice

    2012-01-01

    Context: The development of a consolidated knowledge base for social work requires rigorous approaches to identifying relevant research. Method: The quality of 10 databases and a web search engine were appraised by systematically searching for research articles on resilience and burnout in child protection social workers. Results: Applied Social…

  2. Theoretical studies of oxides relevant to the combustion of fossil fuels

    NASA Astrophysics Data System (ADS)

    Hicks, Jason Michael

    Anthropogenic pollution has greatly increased since the industrial revolution and continues to increase as more of the world becomes dependent upon fossil fuels for important applications like transportation and power production. In a general case, whenever a fossil fuel is consumed, a primary product of a complete combustion reaction is carbon dioxide. In a more specific case, the collection, processing and combustion of coal for power production are one of the primary ways by which trace elements, such as arsenic and selenium, are released into the environment. All of these pollutants are known to have harmful effects, whether on the environment, human health or power production itself. Because of this there has been an increasing interest in studies related to combating these pollutants. Concerning CO2 emissions, recently there has been a significant amount of work related to CO2 capture. A promising method involves the encapsulation of CO2 into isoreticular metal-organic frameworks (IRMOFs). The effectiveness of IMROFs greatly depends on the choice of both metal and organic parts. Molecular simulations have been used in the past to aid in the design and characterization of new MOFs, in particular by generating an adsorption isotherm. However, these traditional simulation methods have several drawbacks. The method used in this thesis, namely expanded Wang-Landau, not only overcomes these drawbacks but provides access to all the thermodynamic properties relevant to the adsorption process through a solution thermodynamics approach. This is greatly beneficial, since an excellent way to characterize the performance of various MOFs is by comparing their desorption free energy, i.e., the energy it takes to regenerate a saturated MOF to prepare it for the next adsorption cycle. Expanded WL was used in the study of CO 2 adsorption into IRMOF-1, 8 and 10 at eight temperatures, spanning both the subcritical and supercritical regimes and the following were obtained

  3. FMRI study relevant to the Mozart effect: brain areas involved in spatial-temporal reasoning.

    PubMed

    Bodner, M; Muftuler, L T; Nalcioglu, O; Shaw, G L

    2001-10-01

    Behavioral studies, motivated by columnar cortical model predictions, have given evidence for music causally enhancing spatial-temporal reasoning. A wide range of behavioral experiments showed that listening to a Mozart Sonata (K.448) gave subsequent enhancements. An EEG coherence study gave evidence for a carryover from that Mozart Sonata listening condition to the subsequent spatial-temporal task in specific cortical regions. Here we present fMRI studies comparing cortical blood flow activation by the Mozart Sonata vs. other music. In addition to expected temporal cortex activation, we report dramatic statistically significant differences in activation by the Mozart Sonata (in comparison to Beethoven's Fur Elise and 1930s piano music) in dorsolateral pre-frontal cortex, occipital cortex and cerebellum, all expected to be important for spatial-temporal reasoning. It would be of great interest to explicitly test this expectation. We propose an fMRI study comparing (subject by subject) brain areas activated in music listening conditions and in spatial-temporal tasks.

  4. An integrated proteomic and metabolomic study on the chronic effects of mercury in Suaeda salsa under an environmentally relevant salinity.

    PubMed

    Liu, Xiaoli; Wu, Huifeng; Ji, Chenglong; Wei, Lei; Zhao, Jianmin; Yu, Junbao

    2013-01-01

    As an environmental contaminant, mercury is of great concern due to its high risk to environmental and human health. The halophyte Suaeda salsa is the dominant plant in the intertidal zones of the Yellow River Delta (YRD) where has been contaminated by mercury in some places. This study aimed at evaluating the chronic effects of mercury (Hg(2+), 20 µg L(-1)) and the influence of an environmentally relevant salinity (NaCl, 500 mM) on mercury-induced effects in S. salsa. A total of 43 protein spots with significant changes were identified in response to Hg(2+), salinity and combined Hg(2+) and salinity. These proteins can be categorized into diverse functional classes, related to metabolic processes, photosynthesis, stress response, protein fate, energy metabolism, signaling pathways and immunosuppression. Metabolic responses demonstrated that Hg(2+) could disturb protein and energy metabolisms in S. salsa co-exposed with or without salinity. In addition, both antagonistic and synergistic effects between Hg(2+) and salinity were confirmed by differential levels of proteins (magnesium-chelatase and ribulose-l,5-bisphosphate carboxylase/oxygenase) and metabolites (valine, malonate, asparagine, glycine, fructose and glucose) in S. salsa. These findings suggest that a combination of proteomics and metabolomics can provide insightful information of environmental contaminant-induced effects in plants at molecular levels.

  5. An Integrated Proteomic and Metabolomic Study on the Chronic Effects of Mercury in Suaeda salsa under an Environmentally Relevant Salinity

    PubMed Central

    Liu, Xiaoli; Wu, Huifeng; Ji, Chenglong; Wei, Lei; Zhao, Jianmin; Yu, Junbao

    2013-01-01

    As an environmental contaminant, mercury is of great concern due to its high risk to environmental and human health. The halophyte Suaeda salsa is the dominant plant in the intertidal zones of the Yellow River Delta (YRD) where has been contaminated by mercury in some places. This study aimed at evaluating the chronic effects of mercury (Hg2+, 20 µg L−1) and the influence of an environmentally relevant salinity (NaCl, 500 mM) on mercury-induced effects in S. salsa. A total of 43 protein spots with significant changes were identified in response to Hg2+, salinity and combined Hg2+ and salinity. These proteins can be categorized into diverse functional classes, related to metabolic processes, photosynthesis, stress response, protein fate, energy metabolism, signaling pathways and immunosuppression. Metabolic responses demonstrated that Hg2+ could disturb protein and energy metabolisms in S. salsa co-exposed with or without salinity. In addition, both antagonistic and synergistic effects between Hg2+ and salinity were confirmed by differential levels of proteins (magnesium-chelatase and ribulose-l,5-bisphosphate carboxylase/oxygenase) and metabolites (valine, malonate, asparagine, glycine, fructose and glucose) in S. salsa. These findings suggest that a combination of proteomics and metabolomics can provide insightful information of environmental contaminant-induced effects in plants at molecular levels. PMID:23696864

  6. Earthdata Search: The Relevance of Relevance

    NASA Technical Reports Server (NTRS)

    Quinn, Patrick

    2016-01-01

    Through recent usability studies, the issue of relevance became increasingly clear in the Earthdata Search Client. After all, if a user can't find the data they are looking for, nothing else we do matters. This presentation walks through usability testing findings and recent relevance improvements made to the Earthdata Search Client.

  7. Kone Ja Keele Uurimine Ning Emakeele Didaktika (Relevance of Linguistic and Psycholinguistic Studies to Mother Tongue Instruction).

    ERIC Educational Resources Information Center

    Karlep, Karl

    This article looks at the relevance of linguistic and psycholinguistic studies to mother tongue instruction. Particularly, the semantically-oriented research of higher level units of language and speech, is considered. As some Estonian studies imply, there are indications that the application of psycholinguistic research in teaching practices…

  8. Relevance of Bt toxin interaction studies for environmental risk assessment of genetically modified crops.

    PubMed

    De Schrijver, Adinda; De Clercq, Patrick; de Maagd, Ruud A; van Frankenhuyzen, Kees

    2015-12-01

    In recent years, different Bacillus thuringiensis (Bt) toxin-encoding genes have been combined or 'stacked' in genetically modified (GM) crops. Synergism between Bt proteins may occur and thereby increase the impact of the stacked GM event on nontarget invertebrates compared to plants expressing a single Bt gene. On the basis of bioassay data available for Bt toxins alone or in combination, we argue that the current knowledge of Bt protein interactions is of limited relevance in environmental risk assessment (ERA).

  9. Epidemiological and histopathological study of relevance of Guizhou Maotai liquor and liver diseases

    PubMed Central

    Wu, Jun; Cheng, Ming-Liang; Zhang, Guo-Hao; Zhai, Rong-Wei; Huang, Neng-Hui; Li, Cheng-Xiu; Luo, Tian-Yong; Lu, Shuang; Yu, Zhi-Qin; Yao, Yu-Mei; Zhang, Ying-Ying; Ren, Lan-Zhen; Ye, Lan; Li, Ling; Zhang, Hui-Na

    2002-01-01

    AIM: To explore the relevance of Maotai liquor and liver diseases. METHODS: Epidemiological study was conducted on groups of subjects, each consisting of 3 subjects from the Maotai liquor group consisting of 99 individuals and one from the non-alcoholic control group consisting of 33 individuals. Liver biopsy was performed on 23 volunteers from Guizhou Maotai Distillery who had a constant and long history of drinking Maotai liquor. Experimental histopathological study was conducted as follows: sixty male Wistar rats were divided into 3 groups randomly and fed with Maotai liquor, ordinary white wine, and physiological saline respectively for a period of 8 and 12 weeks. The rats were sacrificed in batches, then serum ALT, AST, TBil, and AKP were measured. Rat livers were harvested to measure the liver indexes, GSH, and MDA. Histopathological examinations were also performed. Another eighty mice were randomly divided into 4 groups and fed with Maotai (at different dosages of 10 mL·kg-1 and 20 mL·kg-1), ethanol, and physiological saline. The animals were sacrificed after 4 weeks and serum ALT was determined. Then the livers were harvested and liver indexes and MDA were measured. RESULTS: The incidence rate of hepatic symptoms, splenomegaly, liver function impairment, reversal of Albumin/Globulin and increased diameter of portal veins in the Maotai liquor group were 1.0% (1/99), 1.0% (1/99), 1.0% (1/99), 1.0% (1/99), 0 (0/99) and 0 (0/99), 0 (0/99), 0 (0/99), 0 (0/99), 0 (0/99), respectively. There was no significant difference between the Maotai group and the non-alcoholic control group (P > 0.05). Various degree of fatty infiltration of hepatocytes was found in the 23 volunteers receiving liver biopsy, but there was no obvious hepatic fibrosis or cirrhosis. A comparison was made between the Maotai liquor group and the ordinary white wine group. It was found that hepatic MDA in rats and mice were 0.33 ± 0.10 and 0.49 ± 0.23 respectively in Maotai group and 0.61

  10. Relevance of the 1-year dog study in assessing human health risks for registration of pesticides. An update to include pesticides registered in Japan.

    PubMed

    Kobel, Werner; Fegert, Ivana; Billington, Richard; Lewis, Richard; Bentley, Karin; Langrand-Lerche, Carole; Botham, Phil; Sato, Masako; Debruyne, Eric; Strupp, Christian; van Ravenzwaay, Bennard

    2014-11-01

    Over 400 active pesticides are registered in Japan (FAMIC 2013). The results of dog toxicity studies (usually, the 1-year study) were used by the Japanese regulatory authorities to establish the acceptable daily intake (ADI) for 45 pesticide active ingredients (about 9%). A retrospective review of ADIs established in Japan with dog studies as pivotal data for their derivation was performed: the ADIs were reassessed under the assumption that the 1-year dog study would not be available and an alternate ADI was derived based on the remaining toxicology database. In 35 of the 45 cases (77.8%) the ADI resulting from the absence of the 1-year dog study was no greater than twice the Japanese ADI, a difference considered not to be of biological significance. In 6 cases (13%) the resulting ADI was 2-5 times higher, which is considered of questionable biological relevance. On further evaluation of the database, three of these six cases were assessed as to clarify that there is no clear difference and for the other three additional studies to clarify that uncertain findings would have been required. In 3 of the 45 cases (7%) there may be a real difference within the ADI ratio of 2-5. Only in 1 case (2.2%) ADI was five times higher than that has been set. Accordingly, the absence of a 1-year dog study does not appear to influence the ADI derivation in a relevant manner in more than 98% of cases. For the four compounds with a real difference in ADI, consumer exposure would still be well below the alternative ADI. Therefore, a strong case can be made that the standard mandatory requirement to conduct a 1-year dog study, in addition to the 3-month study, is not justified and of no additional value in protecting human health. In addition, a substantial reduction in test animals could be achieved.

  11. Prognostic relevance of DHAP dose-density in relapsed Hodgkin lymphoma: an analysis of the German Hodgkin-Study Group.

    PubMed

    Sasse, Stephanie; Alram, Magdalena; Müller, Horst; Smardová, Lenka; Metzner, Bernd; Doehner, Hartmut; Fischer, Thomas; Niederwieser, Dietger W; Schmitz, Norbert; Schäfer-Eckart, Kerstin; Raemaekers, John M M; Schmalz, Oliver; Tresckow, Bastian V; Engert, Andreas; Borchmann, Peter

    2016-05-01

    Only 50% of patients with relapsed Hodgkin lymphoma (HL) can be cured with intensive induction chemotherapy, followed by high-dose chemotherapy (HDCT) and autologous stem cell transplant (ASCT). Based on the results of the HDR2 trial two courses of DHAP and subsequent HDCT/ASCT are the current standard of care in relapsed HL. In order to assess the prognostic relevance of DHAP dose density, we performed a retrospective multivariate analysis of the HDR2 trial (N=266). In addition to four risk factors (early or multiple relapse, stage IV disease or anemia at relapse, and grade IV hematotoxicity during the first cycle of DHAP) a delayed start of the second cycle of DHAP>day 22 predicted a significantly poorer progression-free survival (PFS, p=0.0356) and overall survival (OS, p=0.0025). In conclusion, our analysis strongly suggests that dose density of DHAP has a relevant impact on the outcome of relapsed HL patients.

  12. Relevance of lipopolysaccharide levels in HIV-associated neurocognitive impairment: the Neuradapt study.

    PubMed

    Vassallo, Matteo; Dunais, Brigitte; Durant, Jacques; Carsenti-Dellamonica, Helene; Harvey-Langton, Alexandra; Cottalorda, Jacqueline; Ticchioni, Michel; Laffon, Muriel; Lebrun-Frenay, Christine; Dellamonica, Pierre; Pradier, Christian

    2013-08-01

    Contributory factors to HIV-associated neurocognitive disorders (HAND) have been shown to include age, co-morbid infections, medication toxicity, virological, genetic and vascular mechanisms, as well as microbial translocation of lipopolysaccharide (LPS), which is suspected to trigger monocyte activation and increase trafficking of infected cells into the brain. In this study, our aim was to assess the degree of neurocognitive impairment in a group of randomly selected HIV-infected patients and investigate potential risk factors, including LPS plasma levels. Furthermore, we evaluated the relevance of LPS as a potential marker for screening patients with mild neurocognitive impairment. LPS plasma levels were compared among patients with HAND and those with no HAND. As LPS has also been shown to be elevated in hepatitis C co-infection, the analysis was stratified according to the presence or not of hepatitis C virus (HCV) co-infection. Differences between groups were evaluated using chi-square tests and Kruskal-Wallis non-parametric tests. Stepwise logistic regression was performed to identify independent risk factors for HAND in the subgroups of HCV-positive and negative patients. A p value <0.05 was considered significant. Analyses were conducted using SPSS® software. From December 2007 to July 2009, 179 patients were tested (mean age 44, 73 % male, 87 % on treatment, 30 % HCV co-infected, median CD4 504/ml and 67 % with viral load below 40 copies/ml). HAND was identified in 40/179 patients (22 %), the majority displaying asymptomatic neurocognitive impairment or mild neurocognitive disorder. Univariate analysis showed that age, illicit drug use, hepatitis C co-infection, prior AIDS-defining events, CD4/CD8 ratio and LPS plasma levels were significantly associated with HAND. The median LPS level was 98.2 pg/ml in the non-HAND group versus 116.1 pg/ml in the HAND group (p < 0.014). No differences were found in LPS values between subgroups of impairment. There was a

  13. The Effects of Topic Familiarity, Author Expertise, and Content Relevance on Norwegian Students' Document Selection: A Mixed Methods Study

    ERIC Educational Resources Information Center

    McCrudden, Matthew T.; Stenseth, Tonje; Bråten, Ivar; Strømsø, Helge I.

    2016-01-01

    This mixed methods study investigated the extent to which author expertise and content relevance were salient to secondary Norwegian students (N = 153) when they selected documents that pertained to more familiar and less familiar topics. Quantitative results indicated that author expertise was more salient for the less familiar topic (nuclear…

  14. Perspectives of Employees with Intellectual Disabilities on Themes Relevant to Their Job Satisfaction. An Explorative Study Using Photovoice

    ERIC Educational Resources Information Center

    Akkerman, Alma; Janssen, Cees G. C.; Kef, Sabina; Meininger, Herman P.

    2014-01-01

    Background: This study explored the perspectives of people with intellectual disabilities on themes relevant to their job satisfaction in integrated and sheltered employment. Method: The photovoice method was used. Nine participants with moderate to mild intellectual disabilities, working in integrated and sheltered employment, took pictures of…

  15. Exploring the Relevance of the Personal and Social Responsibility Model in Adapted Physical Activity: A Collective Case Study

    ERIC Educational Resources Information Center

    Wright, Paul M.; White, Katherine; Gaebler-Spira, Deborah

    2004-01-01

    The purpose of this study was to examine the application of the Personal and Social Responsibility Model (PSRM) in an adapted physical activity program. Although the PSRM was developed for use with underserved youth, scholars in the field of adapted physical activity have noted its potential relevance for children with disabilities. Using a…

  16. Using Relevant Video Clips from Popular Media to Enhance Learning in Large Introductory Psychology Classes: A Pilot Study

    ERIC Educational Resources Information Center

    Rowland-Bryant, Emily; Skinner, Amy L.; Dixon, Lee; Skinner, Christopher H.; Saudargas, Richard

    2011-01-01

    The purpose of this study was to enhance students' learning by supplementing a multimedia lesson with interesting and relevant video clips (VCs). Undergraduate students watched a target material PowerPoint (tmPP) presentation with voice-over lecture covering the Big Five trait theory of personality. Students were randomly assigned to one of four…

  17. Beyond Freedom of Speech and the Public Interest: The Relevance of Critical Legal Studies to Communications Policy.

    ERIC Educational Resources Information Center

    Streeter, Thomas

    1990-01-01

    Explores the implications of critical legal studies (CLS)--a new current in contemporary legal theory--for general discussions of freedom of speech and public interest. Applies CLS concepts to the conflict between broadcasters' and citizens' free speech rights as expressed in the contemporary Fairness Doctrine. Explores CLS's relevance to several…

  18. Student Perception of Relevance of Biology Content to Everyday Life: A Study in Higher Education Biology Courses

    ERIC Educational Resources Information Center

    Himschoot, Agnes Rose

    2012-01-01

    The purpose of this mixed method case study was to examine the effects of methods of instruction on students' perception of relevance in higher education non-biology majors' courses. Nearly ninety percent of all students in a liberal arts college are required to take a general biology course. It is proposed that for many of those students, this is…

  19. The 'species complex' issue in clinically relevant fungi: A case study in Scedosporium apiospermum.

    PubMed

    Chen, Min; Zeng, Jingsi; De Hoog, G Sybren; Stielow, Benjamin; Gerrits Van Den Ende, A H G; Liao, Wanqing; Lackner, Michaela

    2016-02-01

    The genus Scedosporium currently comprises six species, Scedosporium apiospermum, Scedosporium boydii, Pseudallescheria angusta, Scedosporium minutisporum, Scedosporium dehoogii, and Scedosporium aurantiacum, most of which can be distinguished with the primary fungal DNA barcode, the ITS1/2 region of the rDNA gene cluster. In the present study, four additional genetic loci were explored from a phylogenetic point of view enabling a barcoding approach based on K2P pairwise distances to resolve the taxa Scedosporium. We included partial γ-actin (ACT), β-tubulin (BT2), elongation factor 1α (TEF1), and the small ribosomal protein 60S L10 (L1) (RP60S). Phylogenetic inference of each marker individually showed that four out of six species within Scedosporium can be distinguished unambiguously, while strains of S. apiospermum, S. boydii, and P. angusta showed occasional recombination, and accordingly, no genealogical concordance between markers was obtainable. We defined S. apiospermum, S. boydii, and P. angusta as the 'S. apiospermum species complex' since observed differences were not consistent between lineages, and no clinical differences are known between entities within the complex. While BT2 revealed the best performance among the genetic loci tested at the lineage level, barcoding of the ITS region is sufficient for distinction of all entities in Scedosporium at the species or 'complex' level.

  20. The Relevance of Maternal Socioeconomic Characteristics for Low Birth Weight – a Case-Control Study

    PubMed Central

    Altenhöner, T.; Köhler, M.; Philippi, M.

    2016-01-01

    Introduction: The number of children born underweight (low birth weight, LBW) is increasing despite extensive prevention and screening programmes. The cost is high for the health system, and affected children are burdened with health predictors that can affect them negatively throughout their lives. This study investigates to what extent socioeconomic factors, in addition to known medical causes and the health behaviour of pregnant women, influence LBW. Materials and Methods: In this case-control study 131 mothers of singletons with a birth weight ≤ 2500 g (cases) and 323 mothers of normal birth weight babies (controls) were interviewed with respect to socioeconomic status, health behaviour and stress in the workplace. Medical data were collected by specialist staff using a questionnaire. Results: Independent of medical diagnosis and health behaviour, women with lower level education (OR [95 % CI] = 2.24 [1.12; 4.51]) and those who were not working (OR [95 % CI] = 1.82 [1.10; 3.00]) were more likely to have an LBW baby. No effect was shown for immigrant background (OR [95 % CI] = 1.14 [0.59; 2.21]) or stress in the workplace (OR [95 % CI] = 1.17 [0.90; 1.51]). Discussion and Conclusion: These results show that the association between social and health inequalities starts from before birth. In order to reduce the rising number of babies born underweight, socioeconomic determinants in the care and supervision of pregnant women should systematically receive more attention to enable appropriate early preventive strategies to be implemented. PMID:27065486

  1. Study of hot electron spatial energy deposition in spherical targets relevant to shock ignition

    NASA Astrophysics Data System (ADS)

    Zhang, Shu; Wei, M. S.; Krauland, C.; Reynolds, H.; Hoppe, M.; Peebles, J.; Beg, F. N.; Theobald, W.; Borwick, E.; Li, J.; Ren, C.; Stoeckl, C.; Seka, W.; Betti, R.; Campbell, M.

    2016-10-01

    Understanding hot electron generation and coupling is important for the high-intensity shock ignition (SI) inertial confinement fusion concept. Recent hard x-ray experimental data from a SI-relevant platform on OMEGA-60 suggest that <100 keV hot electrons may augment shock pressure by depositing their energy in the solid density region behind the ablation front. These results deduced from simulation are convincing support for electron assisted SI. To further investigate beneficial hot electron characteristics from both high intensity UV and IR lasers in this relevant regime, we performed a joint OMEGA-60/OMEGA EP experiment in the spherical geometry. 60 UV laser beams (18 kJ, 1.8 ns, up to 1015 W/cm2) irradiated a low-density Cu foam ball target with a CH ablator followed by a single IR short pulse laser (2.6 kJ, 100 ps, 1017 W/cm2) at various delays. The electron spatial energy deposition was diagnosed via imaging Cu K α emission with a spherical crystal imager; total K α photon yield and bremsstrahlung radiation were also measured to infer electron spectra. Experimental results are compared with radiation hydrodynamic modeling and will be presented at the meeting. Work supported by the U.S. DOE under contracts DE-NA0002730 (NLUF) and DE-SC0014666.

  2. Animal models of Parkinson's disease: limits and relevance to neuroprotection studies.

    PubMed

    Bezard, Erwan; Yue, Zhenyu; Kirik, Deniz; Spillantini, Maria Grazia

    2013-01-01

    Over the last two decades, significant strides has been made toward acquiring a better knowledge of both the etiology and pathogenesis of Parkinson's disease (PD). Experimental models are of paramount importance to obtain greater insights into the pathogenesis of the disease. Thus far, neurotoxin-based animal models have been the most popular tools employed to produce selective neuronal death in both in vitro and in vivo systems. These models have been commonly referred to as the pathogenic models. The current trend in modeling PD revolves around what can be called the disease gene-based models or etiologic models. The value of utilizing multiple models with a different mechanism of insult rests on the premise that dopamine-producing neurons die by stereotyped cascades that can be activated by a range of insults, from neurotoxins to downregulation and overexpression of disease-related genes. In this position article, we present the relevance of both pathogenic and etiologic models as well as the concept of clinically relevant designs that, we argue, should be utilized in the preclinical development phase of new neuroprotective therapies before embarking into clinical trials.

  3. Clinically relevant depression in old age: An international study with populations from Canada, Latin America and Eastern Europe.

    PubMed

    Ylli, Alban; Miszkurka, Malgorzata; Phillips, Susan P; Guralnik, Jack; Deshpande, Nandini; Zunzunegui, Maria Victoria

    2016-07-30

    Our aim is to assess cross-national variations in prevalence of clinically relevant depression and to examine the relationships of social and health factors with depression in five diverse populations of older adults, from Canada, Brazil, Colombia and Albania. We used the data from the International Mobility in Aging Study. Clinically relevant depression was defined as a score of ≥16 on the Center for Epidemiologic Study Depression Scale (CES-D). Poisson regressions with robust covariance correction were used to estimate prevalence ratios associated with potential risk factors. Prevalence of clinically relevant depression across research sites varied widely, being consistently higher in women than in men. It was lowest in men from Brazil (6.3%) and highest in women from Albania (46.6%). Low education and insufficient income, living alone, multiple chronic conditions, and poor physical performance were all significantly associated with depression prevalence. Poor physical performance was more strongly associated with depression in men than in women. Similar factors are associated with clinically relevant depression among men and women and across research sites. The large variation in depression prevalence population rates is unexplained by the classical individual factors considered in the study suggesting the impact of country characteristics on depression among older populations.

  4. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Engineering and cost studies-addition of generation... TO ELECTRIC LOANS AND GUARANTEES Construction Work Plans and Related Studies § 1710.253 Engineering... engineering and cost studies as specified by RUS. The studies shall cover a period from the beginning of...

  5. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 11 2011-01-01 2011-01-01 false Engineering and cost studies-addition of generation... TO ELECTRIC LOANS AND GUARANTEES Construction Work Plans and Related Studies § 1710.253 Engineering... engineering and cost studies as specified by RUS. The studies shall cover a period from the beginning of...

  6. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 11 2013-01-01 2013-01-01 false Engineering and cost studies-addition of generation... TO ELECTRIC LOANS AND GUARANTEES Construction Work Plans and Related Studies § 1710.253 Engineering... engineering and cost studies as specified by RUS. The studies shall cover a period from the beginning of...

  7. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 11 2014-01-01 2014-01-01 false Engineering and cost studies-addition of generation... TO ELECTRIC LOANS AND GUARANTEES Construction Work Plans and Related Studies § 1710.253 Engineering... engineering and cost studies as specified by RUS. The studies shall cover a period from the beginning of...

  8. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 11 2012-01-01 2012-01-01 false Engineering and cost studies-addition of generation... TO ELECTRIC LOANS AND GUARANTEES Construction Work Plans and Related Studies § 1710.253 Engineering... engineering and cost studies as specified by RUS. The studies shall cover a period from the beginning of...

  9. Part-whole bias in intertemporal choice: An empirical study of additive assumption

    NASA Astrophysics Data System (ADS)

    Lu, Yang; Wu, Dongmei; Zhuang, Xintian

    2016-12-01

    Additive assumption means the overall value of multiple-dated outcomes is based on a simple aggregation of the values of each individual outcome. This assumption is generally accepted in the field of intertemporal choices. However, recent studies show additive assumption is questionable. In this paper, we experimentally tested the additive property of multiple-dated monetary rewards. Our results show: (1) additive assumption does not hold regardless of gain or loss; (2) the sum of subjective values of individual rewards is consistently larger than the valuation placed on the same rewards as a whole. This finding suggests that part-whole bias exists in the context of valuation of intertemporal monetary rewards.

  10. Cross-Cultural Studies of Personality Traits and their Relevance to Psychiatry

    PubMed Central

    Terracciano, Antonio; McCrae, Robert R.

    2009-01-01

    Aims This article provides a brief review of recent cross-cultural research on personality traits at both individual and culture levels, highlighting the relevance of recent findings for psychiatry. Method In most cultures around the world, personality traits can be clearly summarized by the five broad dimensions of the Five-Factor Model (FFM), which makes it feasible to compare cultures on personality and psychopathology. Results Maturational patterns and sex differences in personality traits generally show cultural invariance, which generates the hypothesis that age of onset, clinical evolution, and sex differences in the prevalence of psychiatric disorders might follow similar universal patterns. The average personality profiles from 51 cultures show meaningful geographical distributions and associations with culture-level variables, but are clearly unrelated to national character stereotypes. Conclusions Aggregate personality scores can potentially be related to epidemiological data on psychiatric disorders, and dimensional personality models have implications for psychiatric diagnosis and treatment around the world. PMID:17128620

  11. Study of Aerothermodynamic Modeling Issues Relevant to High-Speed Sample Return Vehicles

    NASA Technical Reports Server (NTRS)

    Johnston, Christopher O.

    2014-01-01

    This paper examines the application of state-of-the-art coupled ablation and radiation simulations to highspeed sample return vehicles, such as those returning from Mars or an asteroid. A defining characteristic of these entries is that the surface recession rates and temperatures are driven by nonequilibrium convective and radiative heating through a boundary layer with significant surface blowing and ablation products. Measurements relevant to validating the simulation of these phenomena are reviewed and the Stardust entry is identified as providing the best relevant measurements. A coupled ablation and radiation flowfield analysis is presented that implements a finite-rate surface chemistry model. Comparisons between this finite-rate model and a equilibrium ablation model show that, while good agreement is seen for diffusion-limited oxidation cases, the finite-rate model predicts up to 50% lower char rates than the equilibrium model at sublimation conditions. Both the equilibrium and finite rate models predict significant negative mass flux at the surface due to sublimation of atomic carbon. A sensitivity analysis to flowfield and surface chemistry rates show that, for a sample return capsule at 10, 12, and 14 km/s, the sublimation rates for C and C3 provide the largest changes to the convective flux, radiative flux, and char rate. A parametric uncertainty analysis of the radiative heating due to radiation modeling parameters indicates uncertainties ranging from 27% at 10 km/s to 36% at 14 km/s. Applying the developed coupled analysis to the Stardust entry results in temperatures within 10% of those inferred from observations, and final recession values within 20% of measurements, which improves upon the 60% over-prediction at the stagnation point obtained through an uncoupled analysis. Emission from CN Violet is shown to be over-predicted by nearly and order-of-magnitude, which is consistent with the results of previous independent analyses. Finally, the

  12. Development of a novel, physiologically relevant cytotoxicity model: Application to the study of chemotherapeutic damage to mesenchymal stromal cells

    SciTech Connect

    May, Jennifer E. Morse, H. Ruth Xu, Jinsheng Donaldson, Craig

    2012-09-15

    There is an increasing need for development of physiologically relevant in-vitro models for testing toxicity, however determining toxic effects of agents which undergo extensive hepatic metabolism can be particularly challenging. If a source of such metabolic enzymes is inadequate within a model system, toxicity from prodrugs may be grossly underestimated. Conversely, the vast majority of agents are detoxified by the liver, consequently toxicity from such agents may be overestimated. In this study we describe the development of a novel in-vitro model, which could be adapted for any toxicology setting. The model utilises HepG2 liver spheroids as a source of metabolic enzymes, which have been shown to more closely resemble human liver than traditional monolayer cultures. A co-culture model has been developed enabling the effect of any metabolised agent on another cell type to be assessed. This has been optimised to enable the study of damaging effects of chemotherapy on mesenchymal stem cells (MSC), the supportive stem cells of the bone marrow. Several optimisation steps were undertaken, including determining optimal culture conditions, confirmation of hepatic P450 enzyme activity and ensuring physiologically relevant doses of chemotherapeutic agents were appropriate for use within the model. The developed model was subsequently validated using several chemotherapeutic agents, both prodrugs and active drugs, with resulting MSC damage closely resembling effects seen in patients following chemotherapy. Minimal modifications would enable this novel co-culture model to be utilised as a general toxicity model, contributing to the drive to reduce animal safety testing and enabling physiologically relevant in-vitro study. -- Highlights: ► An in vitro model was developed for study of drugs requiring hepatic metabolism ► HepG2 spheroids were utilised as a physiologically relevant source of liver enzymes ► The model was optimised to enable study of chemotherapeutic

  13. A relevant study on characteristic parameters of coal combustion and boiler structure

    SciTech Connect

    Zhang, Z.; Zhao, L.; Wun, Y.; Lu, F.

    1997-12-31

    This paper analyzes over 40 power plant coal-fired utility boilers with capacities of more than 200MW and 300MW for its coal particle combustion characteristics, boiler structural parameters and actual condition of boiler performance. Two kinds of parameters of coal particle combustion characteristic and boiler structure are given. They are pulverized coal air jets ignition stability index (Mw), coal-ash slagging index (Mz), coal burn-out index (Mj) as well as boiler structural stability index (Lw), boiler structural slagging index (Lz), boiler structural burn-out index (Lj). The relevant relations between them of Mw-Lw, Mz-Lz and Mj-Lj are set up by interpolation function. This paper also describes a boiler design predicting expert system, with which the design parameters of power plant coal-fired utility boilers with large capacity may be calculated based on coal characteristics parameters and the boiler`s performance be predicted to guarantee power plant coal-fired utility boilers` stable combustion, less slagging and higher combustion efficiency. According to its application to an actual power plant coal-fired utility boiler, the result of prediction is accurate and reliable.

  14. Laboratory Studies of Chemical and Photochemical Processes Relevant to Stratospheric Ozone

    NASA Technical Reports Server (NTRS)

    Villalta, P. W.; Zahniser, M. S.; Nelson, D. D.; Kolb, C. E.

    1998-01-01

    This is the final report for this project. Its purpose is to reduce the uncertainty in rate coefficients for key gas-phase kinetic processes which impact our understanding of stratospheric ozone. The main emphasis of this work is on measuring the rate coefficients for the reactions of HO2 + O3, and HO2 + NO2 in the temperature range (200-240 K) relevant to the lower stratosphere. In order to accomplish this, a high pressure turbulent flow tube reactor was built and its flow characteristics were quantified. The instrument was coupled with tunable diode laser spectroscopy for HO2 detection. Room temperature measurements of the HO2 + NO2 rate coefficients over the pressure range of 50-300 torr agree well with previous measurements. Preliminary measurements of the HO2 + O, rate coefficients at 50 - 300 Torr over the temperature range of 208-294 K agree with the NASA evaluation from 294-225 K but deviate significantly (50 % higher) at approximately 210 K.

  15. Palaeobotanical studies from tropical Africa: relevance to the evolution of forest, woodland and savannah biomes.

    PubMed Central

    Jacobs, Bonnie F

    2004-01-01

    Fossil plants provide data on climate, community composition and structure, all of which are relevant to the definition and recognition of biomes. Macrofossils reflect local vegetation, whereas pollen assemblages sample a larger area. The earliest solid evidence for angiosperm tropical rainforest in Africa is based primarily on Late Eocene to Late Oligocene (ca. 39-26 Myr ago) pollen assemblages from Cameroon, which are rich in forest families. Plant macrofossil assemblages from elsewhere in interior Africa for this time interval are rare, but new work at Chilga in the northwestern Ethiopian Highlands documents forest communities at 28 Myr ago. Initial results indicate botanical affinities with lowland West African forest. The earliest known woodland community in tropical Africa is dated at 46 Myr ago in northern Tanzania, as documented by leaves and fruits from lake deposits. The community around the lake was dominated by caesalpinioid legumes, but included Acacia, for which this, to my knowledge, is the earliest record. This community is structurally similar to modern miombo, although it is different at the generic level. The grass-dominated savannah biome began to expand in the Middle Miocene (16 Myr ago), and became widespread in the Late Miocene (ca. 8 Myr ago), as documented by pollen and carbon isotopes from both West and East Africa. PMID:15519973

  16. Studies on oxidants and antioxidants with a brief glance at their relevance to the immune system.

    PubMed

    Amir Aslani, Banafsheh; Ghobadi, Sirous

    2016-02-01

    Free radical generation occurs continuously within cells as a consequence of common metabolic processes. However, in high concentrations, whether from endogenous or exogenous sources, free radicals can lead to oxidative stress; a harmful process that cause serious damages to all biomolecules in our body hence impairs cell functions and even results in cell death and diseased states. Oxidative injuries accumulate over time and participate in cancer development, cardiovascular and neurodegenerative disorders as well as aging. Nature has bestowed the human body with a complex web of antioxidant defense system including enzymatic antioxidants like glutathione peroxidase and glutathione reductase, catalase and superoxide dismutase as well as non-enzymatic antioxidants such as thiol antioxidants, melatonin, coenzyme Q, and metal chelating proteins, which are efficient enough to fight against excessive free radicals. Also, nutrient antioxidants such as vitamin C, vitamin E, carotenoids, polyphenols, and trace elements are known to have high antioxidant potency to assist in minimizing harmful effects of reactive species. The immune system is also extremely vulnerable to oxidant and antioxidant balance as uncontrolled free radical production can impair its function and defense mechanism. The present paper reviews the ways by which free radicals form in the body and promote tissue damage, as well as the role of the antioxidants defense mechanisms. Finally, we will have a brief glance at oxidants and antioxidants relevance to the immune system.

  17. Palaeobotanical studies from tropical Africa: relevance to the evolution of forest, woodland and savannah biomes.

    PubMed

    Jacobs, Bonnie F

    2004-10-29

    Fossil plants provide data on climate, community composition and structure, all of which are relevant to the definition and recognition of biomes. Macrofossils reflect local vegetation, whereas pollen assemblages sample a larger area. The earliest solid evidence for angiosperm tropical rainforest in Africa is based primarily on Late Eocene to Late Oligocene (ca. 39-26 Myr ago) pollen assemblages from Cameroon, which are rich in forest families. Plant macrofossil assemblages from elsewhere in interior Africa for this time interval are rare, but new work at Chilga in the northwestern Ethiopian Highlands documents forest communities at 28 Myr ago. Initial results indicate botanical affinities with lowland West African forest. The earliest known woodland community in tropical Africa is dated at 46 Myr ago in northern Tanzania, as documented by leaves and fruits from lake deposits. The community around the lake was dominated by caesalpinioid legumes, but included Acacia, for which this, to my knowledge, is the earliest record. This community is structurally similar to modern miombo, although it is different at the generic level. The grass-dominated savannah biome began to expand in the Middle Miocene (16 Myr ago), and became widespread in the Late Miocene (ca. 8 Myr ago), as documented by pollen and carbon isotopes from both West and East Africa.

  18. Perceptions of document relevance

    PubMed Central

    Bruza, Peter; Chang, Vivien

    2014-01-01

    This article presents a study of how humans perceive and judge the relevance of documents. Humans are adept at making reasonably robust and quick decisions about what information is relevant to them, despite the ever increasing complexity and volume of their surrounding information environment. The literature on document relevance has identified various dimensions of relevance (e.g., topicality, novelty, etc.), however little is understood about how these dimensions may interact. We performed a crowdsourced study of how human subjects judge two relevance dimensions in relation to document snippets retrieved from an internet search engine. The order of the judgment was controlled. For those judgments exhibiting an order effect, a q–test was performed to determine whether the order effects can be explained by a quantum decision model based on incompatible decision perspectives. Some evidence of incompatibility was found which suggests incompatible decision perspectives is appropriate for explaining interacting dimensions of relevance in such instances. PMID:25071622

  19. Assessment of potential advantages of relevant ions for particle therapy: A model based study

    SciTech Connect

    Grün, Rebecca; Friedrich, Thomas; Krämer, Michael; Scholz, Michael; Zink, Klemens; Durante, Marco; Engenhart-Cabillic, Rita

    2015-02-15

    Purpose: Different ion types offer different physical and biological advantages for therapeutic applications. The purpose of this work is to assess the advantages of the most commonly used ions in particle therapy, i.e., carbon ({sup 12}C), helium ({sup 4}He), and protons ({sup 1}H) for different treatment scenarios. Methods: A treatment planning analysis based on idealized target geometries was performed using the treatment planning software TRiP98. For the prediction of the relative biological effectiveness (RBE) that is required for biological optimization in treatment planning the local effect model (LEM IV) was used. To compare the three ion types, the peak-to-entrance ratio (PER) was determined for the physical dose (PER{sub PHY} {sub S}), the RBE (PER{sub RBE}), and the RBE-weighted dose (PER{sub BIO}) resulting for different dose-levels, field configurations, and tissue types. Further, the dose contribution to artificial organs at risk (OAR) was assessed and a comparison of the dose distribution for the different ion types was performed for a patient with chordoma of the skull base. Results: The study showed that the advantages of the ions depend on the physical and biological properties and the interplay of both. In the case of protons, the consideration of a variable RBE instead of the clinically applied generic RBE of 1.1 indicates an advantage in terms of an increased PER{sub RBE} for the analyzed configurations. Due to the fact that protons show a somewhat better PER{sub PHY} {sub S} compared to helium and carbon ions whereas helium shows a higher PER{sub RBE} compared to protons, both protons and helium ions show a similar RBE-weighted dose distribution. Carbon ions show the largest variation of the PER{sub RBE} with tissue type and a benefit for radioresistant tumor types due to their higher LET. Furthermore, in the case of a two-field irradiation, an additional gain in terms of PER{sub BIO} is observed when using an orthogonal field configuration

  20. Nanoparticle dispersion in environmentally relevant culture media: a TiO2 case study and considerations for a general approach

    NASA Astrophysics Data System (ADS)

    Horst, Allison M.; Ji, Zhaoxia; Holden, Patricia A.

    2012-08-01

    Nanoparticle exposure in toxicity studies requires that nanoparticles are bioavailable by remaining highly dispersed in culture media. However, reported dispersion approaches are variable, mostly study-specific, and not transferable owing to their empirical basis. Furthermore, many published approaches employ proteinaceous dispersants in rich laboratory media, both of which represent end members in environmental scenarios. Here, a systematic approach was developed to disperse initially agglomerated TiO2 nanoparticles (Aeroxide® TiO2 P25, Evonik, NJ; primary particle size range 6.4-73.8 nm) in oligotrophic culture medium for environmentally relevant bacterial toxicity studies. Based on understanding particle-particle interactions in aqueous media and maintaining environmental relevance, the approach involves (1) quantifying the relationship between pH and zeta potential to determine the point of zero charge of select nanoparticles in water; (2) nominating, then testing and selecting, environmentally relevant stabilizing agents; and (3) dispersing via "condition and capture" whereby stock dry powder nanoparticles are sonicated in pre-conditioned (with base, or acid, plus stabilizing agent) water, then diluted into culture media. The "condition and capture" principle is transferable to other nanoparticle and media chemistries: simultaneously, mechanically and electrostatically, nanoparticles can be dispersed with surrounding stabilizers that coat and sterically hinder reagglomeration in the culture medium.

  1. Evaluating Drugs and Food Additives for Public Use: A Case Studies Approach.

    ERIC Educational Resources Information Center

    Merritt, Sheridan V.

    1980-01-01

    Described is a case study used in an introductory college biology course that provides a basis for generating debate on an issue concerning the regulation of controversial food additives and prescription drugs. The case study contained within this article deals with drug screening, specifically with information related to thalidomide. (CS)

  2. Experimental Study of Water Cluster Molecules with Relevance to Mesospheric Clouds

    NASA Astrophysics Data System (ADS)

    Robertson, Scott; Sternovsky, Zoltan; Horanyi, Mihaly

    2000-10-01

    We have begun an experimental investigation of the properties of the water cluster molecules responsible for clouds occurring in the polar mesopause. These clusters disturb the charge balance in the ionosphere by attaching electrons which then creates localized reductions in the electron density. A supersonic nozzle sprays a mixture of water vapor and argon into vacuum and the expansion leads to condensation of clusters with 4 to 11 water molecules. Initial measurements are of the collision cross section of these molecules with neutral gas. The cross sections have a minimum at six waters consistent with the tighter molecular arrangement predicted for this cluster number. Additional measurements are underway for charging processes.

  3. Combining experimental and computational studies to understand and predict reactivities of relevance to homogeneous catalysis.

    PubMed

    Tsang, Althea S-K; Sanhueza, Italo A; Schoenebeck, Franziska

    2014-12-08

    This article showcases three major uses of computational chemistry in reactivity studies: the application after, in combination with, and before experiment. Following a brief introduction of suitable computational tools, challenges and opportunities in the implementation of computational chemistry in reactivity studies are discussed, exemplified with selected case studies from our and other laboratories.

  4. [TG-FTIR study on pyrolysis of wheat-straw with abundant CaO additives].

    PubMed

    Han, Long; Wang, Qin-Hui; Yang, Yu-Kun; Yu, Chun-Jiang; Fang, Meng-Xiang; Luo, Zhong-Yang

    2011-04-01

    Biomass pyrolysis in presence of abundant CaO additives is a fundamental process prior to CaO sorption enhanced gasification in biomass-based zero emission system. In the present study, thermogravimetric Fourier transform infrared (TG-FTIR) analysis was adopted to examine the effects of CaO additives on the mass loss process and volatiles evolution of wheat-straw pyrolysis. Observations from TG and FTIR analyses simultaneously demonstrated a two-stage process for CaO catalyzed wheat-straw pyrolysis, different from the single stage process for pure wheat-straw pyrolysis. CaO additives could not only absorb the released CO2 but also reduce the yields of tar species such as toluene, phenol, and formic acid in the first stage, resulting in decreased mass loss and maximum mass loss rate in this stage with an increase in CaO addition. The second stage was attributed to the CaCO3 decomposition and the mass loss and maximum mass loss rate increased with increasing amount of CaO additives. The results of the present study demonstrated the great potential of CaO additives to capture CO2 and reduce tars yields in biomass-based zero emission system. The gasification temperature in the system should be lowered down to avoid CaCO3 decomposition.

  5. Study raises questions about measurement of 'additionality,'or maintaining domestic health spending amid foreign donations.

    PubMed

    Garg, Charu C; Evans, David B; Dmytraczenko, Tania; Izazola-Licea, José-Antonio; Tangcharoensathien, Viroj; Ejeder, Tessa Tan-Torres

    2012-02-01

    Donor nations and philanthropic organizations increasingly require that funds provided for a specific health priority such as HIV should supplement domestic spending on that priority-a concept known as "additionality." We investigated the "additionality" concept using data from Honduras, Rwanda, and Thailand, and we found that the three countries increased funding for HIV in response to increased donor funding. In contrast, the study revealed that donors, faced with increased Global Fund resources for HIV in certain countries, tended to decrease their funding for HIV or shift funds for use in non-HIV health areas. More broadly, we found many problems in the measurement and interpretation of additionality. These findings suggest that it would be preferable for donors and countries to agree on how best to use available domestic and external funds to improve population health, and to develop better means of tracking outcomes, than to try to develop more sophisticated methods to track additionality.

  6. Integrating experimental (in vitro and in vivo) neurotoxicity studies of low-dose thimerosal relevant to vaccines.

    PubMed

    Dórea, José G

    2011-06-01

    There is a need to interpret neurotoxic studies to help deal with uncertainties surrounding pregnant mothers, newborns and young children who must receive repeated doses of Thimerosal-containing vaccines (TCVs). This review integrates information derived from emerging experimental studies (in vitro and in vivo) of low-dose Thimerosal (sodium ethyl mercury thiosalicylate). Major databases (PubMed and Web-of-science) were searched for in vitro and in vivo experimental studies that addressed the effects of low-dose Thimerosal (or ethylmercury) on neural tissues and animal behaviour. Information extracted from studies indicates that: (a) activity of low doses of Thimerosal against isolated human and animal brain cells was found in all studies and is consistent with Hg neurotoxicity; (b) the neurotoxic effect of ethylmercury has not been studied with co-occurring adjuvant-Al in TCVs; (c) animal studies have shown that exposure to Thimerosal-Hg can lead to accumulation of inorganic Hg in brain, and that (d) doses relevant to TCV exposure possess the potential to affect human neuro-development. Thimerosal at concentrations relevant for infants' exposure (in vaccines) is toxic to cultured human-brain cells and to laboratory animals. The persisting use of TCV (in developing countries) is counterintuitive to global efforts to lower Hg exposure and to ban Hg in medical products; its continued use in TCV requires evaluation of a sufficiently nontoxic level of ethylmercury compatible with repeated exposure (co-occurring with adjuvant-Al) during early life.

  7. Reasserting the Relevance of the Social Studies: An Emerging Model for Collaborative Cross-State Research

    ERIC Educational Resources Information Center

    Passe, Jeff; Patterson, Nancy

    2011-01-01

    There is a timely movement afoot to secure the rightful place of social studies as a core part of curriculum at a time when it is increasingly compromised across the nation. The authors present a model that accepts the call to consider the enterprise of social studies research and broaden it to address the needs of the day. They offer a brief…

  8. Relevance Revisited: Curriculum Development in the Humanities. No. IV: Local Studies and Experiential Learning.

    ERIC Educational Resources Information Center

    Mondale, Clarence C., Ed.

    Papers presented at an April 1977 workshop assessing the growing interest in making local materials the subject of study in the humanities are provided. Section I contains three background papers: "The Local-Global Studies Paradox," by John Badgley; "Community History: The Roots of the Problem," by D'Ann Campbell; and "An…

  9. Linguistically-Relevant Diachronic Study of Cultural Values in Early British Advertising Discourse

    ERIC Educational Resources Information Center

    Kochetova, Larisa A.

    2016-01-01

    Drawing on linguistic data retrieved from early advertisements published in British newspapers between 1788 and 1900, the study seeks to map out a set of values and account for linguistic means used to codify them in the diachronic perspective. For the purposes of the study, the corpus of advertisements from random issues of British newspapers…

  10. Reports on Swedish Projects Relevant to the Study of Impromptu Speech: Talsyntax.

    ERIC Educational Resources Information Center

    Loman, Bengt

    The project Talsyntax (Syntax of Spoken Swedish), part of a large-scale study of modern Swedish language usage, examined the general characteristics and peculiarities of spoken Swedish. Three important aspects of the study are data collection, methodological results, and empirical results. The data collection effort has produced an archive of…

  11. [Bootstrap method-based estimation on the confidence interval for additive interaction in cohort studies].

    PubMed

    Pan, Jin-ren; Chen, Kun

    2010-07-01

    Interaction assessment is an important step in epidemiological analysis. When etiological study is carried out, the logarithmic models such as logistic model or Cox proportional hazard model are commonly used to estimate the independent effects of the risk factors. However, estimating interaction between risk factors by the regression coefficient of the product term is on multiplicative scale, and for public-health purposes, it is supposed to be on additive scale or departure from additivity. This paper illustrates with a example of cohort study by fitting Cox proportional hazard model to estimate three measures for additive interaction which presented by Rothman. Adopting the S-Plus application with a built-in Bootstrap function, it is convenient to estimate the confidence interval for additive interaction. Furthermore, this method can avoid the exaggerated estimation by using ORs in a cohort study to gain better precision. When using the complex combination models between additive interaction and multiplicative interaction, it is reasonable to choose the former one when the result is inconsistent.

  12. Uncovering study abroad: foreignness and its relevance to nurse education and cultural competence.

    PubMed

    Greatrex-White, Sheila

    2008-07-01

    This paper reports some of the findings from a hermeneutic phenomenological research project designed to uncover the nature of the phenomenon 'study abroad' in the context of Nursing Higher Education in the United Kingdom. The research question asked was 'How is study abroad manifest in the experience of nursing students?' Informed by the philosophy of Martin Heidegger, the analysis of 26 study abroad students' diary accounts uncovered six general structures, or ways for study abroad to be, namely; leaving behind, escape, foreigner, self-discovery, learning and risk. The focus here is on the general structure 'foreigner' and the far-reaching implications this can have in terms of understanding how study abroad comes to be. The relationship between study abroad, positive disturbance and the development of students who are able to recognise diversity across different cultures is discussed. It is suggested that if one of the major aims of nurse higher education is the development of culturally competent practitioners, study abroad is deserving of far greater attention than is currently the case.

  13. Relevant Studies for NERC’s Analysis of EPA's Clean Power Plan 111 (d) Compliance

    SciTech Connect

    Ahlstrom, Mark; Smith, Charlie; Piwko, Dick; Lew, Debra; Bloom, Aaron; Mai, Trieu; Clark, Kara; Milligan, Michael

    2015-06-12

    The purpose of this paper is to describe multiple studies of wind and solar integration that have found CO2 reductions of approximately 30%. These studies can be viewed in several ways, including as viable paths to compliance with the EPA rule, alternative ''bookend cases'' to compare to compliance based largely on natural gas, or something in between. The studies in this paper represent a body of work that can help inform the public discussion surrounding the cost and reliability impacts of complying with the proposed EPA CPP.

  14. [The Philosophical Relevance of the Study of Schizophrenia. Methodological and Conceptual Issues].

    PubMed

    López-Silva, Pablo

    2014-01-01

    The study of mental illness involves profound methodological and philosophical debates. This article explores the disciplinary complementarity, particularly, between philosophy of mind, phenomenology, and empirical studies in psychiatry and psychopathology in the context of the understanding of schizophrenia. After clarifying the possible role of these disciplines, it is explored the way in which a certain symptom of schizophrenia (thought insertion) challenges the current phenomenological approach to the relationship between consciousness and self-awareness. Finally, it is concluded that philosophy of mind, phenomenology, and empirical studies in psychiatry and psychopathology should, necessarily, regulate their progress jointly in order to reach plausible conclusions about what we call 'schizophrenia'.

  15. Components of plastic: experimental studies in animals and relevance for human health

    PubMed Central

    Talsness, Chris E.; Andrade, Anderson J. M.; Kuriyama, Sergio N.; Taylor, Julia A.; vom Saal, Frederick S.

    2009-01-01

    Components used in plastics, such as phthalates, bisphenol A (BPA), polybrominated diphenyl ethers (PBDE) and tetrabromobisphenol A (TBBPA), are detected in humans. In addition to their utility in plastics, an inadvertent characteristic of these chemicals is the ability to alter the endocrine system. Phthalates function as anti-androgens while the main action attributed to BPA is oestrogen-like activity. PBDE and TBBPA have been shown to disrupt thyroid hormone homeostasis while PBDEs also exhibit anti-androgen action. Experimental investigations in animals indicate a wide variety of effects associated with exposure to these compounds, causing concern regarding potential risk to human health. For example, the spectrum of effects following perinatal exposure of male rats to phthalates has remarkable similarities to the testicular dysgenesis syndrome in humans. Concentrations of BPA in the foetal mouse within the range of unconjugated BPA levels observed in human foetal blood have produced effects in animal experiments. Finally, thyroid hormones are essential for normal neurological development and reproductive function. Human body burdens of these chemicals are detected with high prevalence, and concentrations in young children, a group particularly sensitive to exogenous insults, are typically higher, indicating the need to decrease exposure to these compounds. PMID:19528057

  16. Comparative study of electrolyte additives using electrochemical impedance spectroscopy on symmetric cells

    NASA Astrophysics Data System (ADS)

    Petibon, R.; Sinha, N. N.; Burns, J. C.; Aiken, C. P.; Ye, Hui; VanElzen, Collette M.; Jain, Gaurav; Trussler, S.; Dahn, J. R.

    2014-04-01

    The effect of various electrolyte additives and additive combinations added to a 1 M LiPF6 EC:EMC electrolyte on the positive and negative electrodes surface of 1 year old wound LiCoO2/graphite cells and Li[Ni0.4Mn0.4Co0.2])O2/graphite cells was studied using electrochemical impedance spectroscopy (EIS) on symmetric cells. The additives tested were: vinylene carbonate (VC), trimethoxyboroxine (TMOBX), fluoroethylene carbonate (FEC), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and H2O alone or in combination. In general, compared to control electrolyte, the additives tested reduced the impedance of the positive electrode and increased the impedance of the negative electrode with the exception of LiTFSI in Li[Ni0.4Mn0.4Co0.2]O2/graphite wound cells. Higher charge voltage led to higher positive electrode impedance, with the exception of 2%VC + 2% FEC, and 2% LiTFSI. In some cases, some additives when mixed with another controlled the formation of the SEI at one electrode, and shared the formation of the SEI at one electrode when mixed with a different additive.

  17. [Relevance of animal models in the study of human pathologies: a mouse model of Down syndrome].

    PubMed

    Morice, Elise

    2010-01-01

    Animal models provide a simplified representation of biological systems impossible to study directly in the human being. Regarding genetic pathologies, mouse models are the most studied since they enable to reproduce in animals the mutation of the gene or genes responsible for the disease and to study the phenotypic consequences. Down syndrome is a genetic disorder arising from the presence of a third copy of the human chromosome 21 (Hsa21) and is characterized by different degrees of phenotypic alterations including morphological, cardiac, muscular, cerebral, motor and intellectual changes. This high phenotypic heterogeneity involves genetic and environmental effects, which are impossible to dissect out in human beings. Various models in mice have been developed in order to identify the genetic and neurobiological mechanisms responsible for Down syndrome. The Tc1 mouse is the most complete genetic animal model currently available to study Down syndrome, since it carries an almost complete Hsa 21. The behavioural and electrophysiological studies of this model reveal a great similarity between the animal phenotype and the Down syndrome symptomatology, consequently this model represents a powerful genetic tool with a potential to unravel the mechanisms underlying the deficiencies array characteristic of this human condition. In the long term, Tc1 mice will contribute to the development and the screening of new therapeutics, with the goal of improving all the impairments reported in Down syndrome.

  18. Generating Scenarios of Addition and Subtraction: A Study of Japanese University Students

    ERIC Educational Resources Information Center

    Kinda, Shigehiro

    2013-01-01

    Students are presented with problems involving three scenario types of addition and subtraction in elementary mathematics: one dynamic ("Change") and two static ("Combine, Compare"). Previous studies have indicated that the dynamic type is easier for school children, whereas the static types are more difficult and comprehended only gradually…

  19. Performance on Addition and Subtraction Problems: Results from Individual Interviews - Sandy Bay Study.

    ERIC Educational Resources Information Center

    Romberg, Thomas A.; And Others

    The purpose of this study was to relate children's cognitive processing capabilities and their grade level to their performance and to the strategies they used when working addition and subtraction problems. From two sets of data which assessed memory capacity and cognitive processing capacities, six groups of children with different cognitive…

  20. Using E-Learning to Enhance the Learning of Additional Languages--A Pilot Comparative Study

    ERIC Educational Resources Information Center

    Hilton, Gillian L. S.

    2013-01-01

    This paper is concerned with a small pilot study to ascertain the use of, and changes in the use of e-learning to promote the learning of foreign and additional languages in a variety of countries in Europe. It was undertaken by individual researchers in an attempt to examine how the drive towards the teaching of new languages, encouraged by the…

  1. Industry research on the use and effects of levulinic acid: a case study in cigarette additives.

    PubMed

    Keithly, Lois; Ferris Wayne, Geoffrey; Cullen, Doris M; Connolly, Gregory N

    2005-10-01

    Public health officials and tobacco researchers have raised concerns about the possible contributions of additives to the toxicity of cigarettes. However, little attention has been given to the process whereby additives promote initiation and addiction. Levulinic acid is a known cigarette additive. Review of internal tobacco industry documents indicates that levulinic acid was used to increase nicotine yields while enhancing perceptions of smoothness and mildness. Levulinic acid reduces the pH of cigarette smoke and desensitizes the upper respiratory tract, increasing the potential for cigarette smoke to be inhaled deeper into the lungs. Levulinic acid also may enhance the binding of nicotine to neurons that ordinarily would be unresponsive to nicotine. These findings held particular interest in the internal development of ultralight and so-called reduced-exposure cigarette prototypes. Industry studies found significantly increased peak plasma nicotine levels in smokers of ultralight cigarettes following addition of levulinic acid. Further, internal studies observed changes in mainstream and sidestream smoke composition that may present increased health risks. The use of levulinic acid illustrates the need for regulatory authority over tobacco products as well as better understanding of the role of additives in cigarettes and other tobacco products.

  2. Proposal for defining the relevance of drug accumulation derived from single dose study data for modified release dosage forms.

    PubMed

    Scheerans, Christian; Heinig, Roland; Mueck, Wolfgang

    2015-03-01

    Recently, the European Medicines Agency (EMA) published the new draft guideline on the pharmacokinetic and clinical evaluation of modified release (MR) formulations. The draft guideline contains the new requirement of performing multiple dose (MD) bioequivalence studies, in the case when the MR formulation is expected to show 'relevant' drug accumulation at steady state (SS). This new requirement reveals three fundamental issues, which are discussed in the current work: first, measurement for the extent of drug accumulation (MEDA) predicted from single dose (SD) study data; second, its relationship with the percentage residual area under the plasma concentration-time curve (AUC) outside the dosing interval (τ) after SD administration, %AUC(τ-∞)SD ; and third, the rationale for a threshold of %AUC(τ-∞)SD that predicts 'relevant' drug accumulation at SS. This work revealed that the accumulation ratio RA,AUC , derived from the ratio of the time-averaged plasma concentrations during τ at SS and after SD administration, respectively, is the 'preferred' MEDA for MR formulations. A causal relationship was derived between %AUC(τ-∞)SD and RA,AUC , which is valid for any drug (product) that shows (dose- and time-) linear pharmacokinetics regardless of the shape of the plasma concentration-time curve. Considering AUC thresholds from other guidelines together with the causal relationship between %AUC(τ-∞)SD and RA,AUC indicates that values of %AUC(τ-∞)SD ≤ 20%, resulting in RA,AUC ≤ 1.25, can be considered as leading to non-relevant drug accumulation. Hence, the authors suggest that 20% for %AUC(τ-∞)SD is a reasonable threshold and selection criterion between SD or MD study designs for bioequivalence studies of new MR formulations.

  3. Mahatma Gandhi and Character Education in Non-Violence: Its Relevance in Religious Studies Today

    ERIC Educational Resources Information Center

    Damm, Alex

    2011-01-01

    This essay presents educational principles of Mahatma Gandhi, specifically principles of character education, as a model for strengthening non-violence in students. Its major concern is to show that Gandhi's ideal of non-violent character education is important for university teaching in disciplines including religious studies, and that Gandhi…

  4. Culturally Relevant Pedagogy and Behaviors: A Study of Faculty Beliefs at Six Christian Postsecondary Institutions

    ERIC Educational Resources Information Center

    Taylor, Deborah L.

    2013-01-01

    This study explored the perspectives of faculty at six evangelical Christian universities concerning cultural diversity and how theological beliefs might impact faculty members' commitment to a culturally competent pedagogy. A mixed methods design employing both quantitative (survey) and qualitative (interviews) was utilized for data collection.…

  5. Study of {sup 24}Mg resonances relevant for carbon burning nucleosynthesis

    SciTech Connect

    Tokić, V.; Soić, N.; Blagus, S.; Fazinić, S.; Jelavić-Malenica, D.; Miljanić, D.; Prepolec, L.; Skukan, N.; Szilner, S.; Uroić, M.; Milin, M.; Di Pietro, A.; Figuera, P.; Fisichella, M.; Lattuada, M.; Scuderi, V.; Strano, E.; Torresi, D.; Freer, M.; Ziman, V.; and others

    2014-05-09

    We have studied decays of resonances in {sup 24}Mg at excitation energies above the {sup 12}C+{sup 12}C decay threshold, using {sup 12}C({sup 16}O,α){sup 24}Mg* reaction. This experiment has been performed at INFNLNS, using Tandem accelerator beam of 16O at E = 94 MeV. Some preliminary results are presented.

  6. Moodle as a Data Portal in a Study of Cultural Relevance in K-2 Mathematics

    ERIC Educational Resources Information Center

    Marshall, Patricia L.

    2013-01-01

    This article describes a multiyear research project involving practicing K-2 teachers and the incorporation of Moodle as a qualitative data portal. Utilizing a case study of two participants, findings from the Moodle-facilitated data point known as "e-forum" are used to examine whether the community-building goal of the research was…

  7. Case Studies of Leading Edge Small Urban High Schools. Relevance Strategic Designs: 6. Perspectives Charter School

    ERIC Educational Resources Information Center

    Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

    2008-01-01

    This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

  8. Culturally Relevant, Purpose-Driven Learning & Teaching in a Middle School Social Studies Classroom

    ERIC Educational Resources Information Center

    Milner, H. Richard, IV

    2014-01-01

    In an era of student testing by any means necessary, it has become increasingly rare to locate teachers who are committed to teaching students to improve society because they are instead under immense pressure to raise test scores (Darling-Hammond, 2010; Ladson-Billings, 2006). Ms. Shaw, the social studies teacher discussed in this article, is…

  9. Influencing Tomorrow: A Study of Emerging Influence Techniques and Their Relevance to United States Information Operations

    DTIC Science & Technology

    2015-06-12

    offers insights into an international network that has preserved a holistic identity, while simultaneously franchising globally. The Islamic State...preserved a holistic identity, while simultaneously franchising globally. The Islamic State of Iraq and the Levant is the second study and an

  10. Diving physiology of seabirds and marine mammals: Relevance, challenges and some solutions for field studies.

    PubMed

    Andrews, Russel D; Enstipp, Manfred R

    2016-12-01

    To fully understand how diving seabirds and marine mammals balance the potentially conflicting demands of holding their breath while living their lives underwater (and maintaining physiological homeostasis during exercise, feeding, growth, and reproduction), physiological studies must be conducted with animals in their natural environments. The purpose of this article is to review the importance of making physiological measurements on diving animals in field settings, while acknowledging the challenges and highlighting some solutions. The most extreme divers are great candidates for study, especially in a comparative and mechanistic context. However, physiological data are also required of a wide range of species for problems relating to other disciplines, in particular ecology and conservation biology. Physiological data help with understanding and predicting the outcomes of environmental change, and the direct impacts of anthropogenic activities. Methodological approaches that have facilitated the development of field-based diving physiology include the isolated diving hole protocol and the translocation paradigm, and while there are many techniques for remote observation, animal-borne biotelemetry, or "biologging", has been critical. We discuss issues related to the attachment of instruments, the retrieval of data and sensing of physiological variables, while also considering negative impacts of tagging. This is illustrated with examples from a variety of species, and an in-depth look at one of the best studied and most extreme divers, the emperor penguin (Aptenodytes forsteri). With a variety of approaches and high demand for data on the physiology of diving seabirds and marine mammals, the future of field studies is bright.

  11. Anti-Aß immunotherapy in Alzheimer's disease; relevance of transgenic mouse studies to clinical trials

    PubMed Central

    Wilcock, Donna M.; Colton, Carol A.

    2009-01-01

    Therapeutic approaches to the treatment of Alzheimer's disease are focused primarily on the Aß peptide which aggregates to form amyloid deposits in the brain. The amyloid hypothesis states that amyloid is the precipitating factor that results in the other pathologies of Alzheimer's, namely neurofibrillary tangles and neurodegeneration, as well as the clinical dementia. One such therapy that has attracted significant attention is anti-Aß immunotherapy. First described in 1999, immunotherapy uses anti-Aß antibodies to lower brain amyloid levels. Active immunization, in which Aß is combined with an adjuvant to stimulate an immune response producing antibodies and passive immunization, in which antibodies are directly injected, were shown to lower brain amyloid levels and improve cognition in multiple transgenic mouse models. Mechanisms of action were studied in these mice and revealed a complex set of mechanisms that depended on the type of antibody used. When active immunization advanced to clinical trials a subset of patients developed meningoencephalitis; an event not predicted in mouse studies. However, it was suspected that a T-cell response due to the type of adjuvant used was the cause of the meningoencephalitis and studies in mice indicated alternative methods of vaccination. Passive immunization has also advanced to phase III clinical trials on the basis of successful transgenic mouse studies. Reports from the active immunization clinical trial indicated that, indeed, amyloid levels in brain were reduced. While APP transgenic mouse models are useful in studying amyloid pathology these mice do not generate significant tau pathology or neuron loss. Continued development of new mouse models that do generate all of these pathologies will be critical in more accurately testing therapeutics and predicting the clinical outcome of such therapeutics. PMID:19096156

  12. Anatomically ordered tapping interferes more with one-digit addition than two-digit addition: a dual-task fMRI study.

    PubMed

    Soylu, Firat; Newman, Sharlene D

    2016-02-01

    Fingers are used as canonical representations for numbers across cultures. In previous imaging studies, it was shown that arithmetic processing activates neural resources that are known to participate in finger movements. Additionally, in one dual-task study, it was shown that anatomically ordered finger tapping disrupts addition and subtraction more than multiplication, possibly due to a long-lasting effect of early finger counting experiences on the neural correlates and organization of addition and subtraction processes. How arithmetic task difficulty and tapping complexity affect the concurrent performance is still unclear. If early finger counting experiences have bearing on the neural correlates of arithmetic in adults, then one would expect anatomically and non-anatomically ordered tapping to have different interference effects, given that finger counting is usually anatomically ordered. To unravel these issues, we studied how (1) arithmetic task difficulty and (2) the complexity of the finger tapping sequence (anatomical vs. non-anatomical ordering) affect concurrent performance and use of key neural circuits using a mixed block/event-related dual-task fMRI design with adult participants. The results suggest that complexity of the tapping sequence modulates interference on addition, and that one-digit addition (fact retrieval), compared to two-digit addition (calculation), is more affected from anatomically ordered tapping. The region-of-interest analysis showed higher left angular gyrus BOLD response for one-digit compared to two-digit addition, and in no-tapping conditions than dual tapping conditions. The results support a specific association between addition fact retrieval and anatomically ordered finger movements in adults, possibly due to finger counting strategies that deploy anatomically ordered finger movements early in the development.

  13. Endpoint measures in the mdx mouse relevant for muscular dystrophy pre-clinical studies

    PubMed Central

    Kobayashi, Yvonne M.; Rader, Erik P.; Crawford, Robert W.; Campbell, Kevin P.

    2011-01-01

    Loss of mobility influences the quality of life for patients with neuromuscular diseases. Common measures of mobility and chronic muscle damage are the six-minute walk test and serum creatine kinase. Despite extensive pre-clinical studies of therapeutic approaches, characterization of these measures is incomplete. To address this, a six-minute ambulation assay, serum creatine kinase, and myoglobinuria were investigated for the mdx mouse, a dystrophinopathy mouse model commonly used in pre-clinical studies. Mdx mice ambulated shorter distances than normal controls, a disparity accentuated after mild exercise. An asymmetric pathophysiology in mdx mice was unmasked with exercise, and peak measurements of serum creatine kinase and myoglobinuria were identified. Our data highlights the necessity to consider asymmetric pathology and timing of biomarkers when testing potential therapies for muscular dystrophy. PMID:22154712

  14. Astronomical relevance of materials from Earth and space: A laboratory study

    NASA Astrophysics Data System (ADS)

    Rauf, Kani Mustafa

    The present study used scanning and transmission electron microscopy, energy dispersive analysis of X-rays (EDAX) and spectroscopy (FTIR, UV-Visible and fluorescence) to examine terrestrial materials of possible astronomical significance (Oedogonium sp., Enteromopha intestinalis, Pelvetia canaliculata, Fucus vesiculosus, Bacillus cereus, Staphyllococcus aureus, poppy seed, chlorophylls 'a' and 'b', Panicum maximum, anthracite, bituminous coal, naphthalene), the Tagish lake and Carancas meteorites, a Kerala red rain sample and stratospheric air particles collected at altitudes of 38-41 km. The study was designed to determine if any of the terrestrial samples could be proposed as an effective model for the interpretation of astronomical spectroscopic observations. The study also set out to search for evidence to shed light on the origin of these meteorites, red rain and stratospheric air particles. The spectra of all the terrestrial samples (including the meteorites) exhibited absorptions in the Mid-IR region, similar to astronomical features displayed by a variety of galactic sources. Algae (Odeogonium sp.) in particular produced the largest number of absorption peaks, most of which matched those of the astronomical emission spectra of PPNe and also the UIBs. Based on these observations, algae could be defended as a biological model for the interpretation of UIBs and PPNe, and a potential candidate for interstellar material. Coal and semi anthracite, that can be regarded as steps in the degradation of biomaterial, preserve the UIB-PPNe spectral features to varying degrees. The results are consistent with the panspermia theory of Hoyle and Wickramasinghe. UV-Visible studies were also conducted on all these materials. The main absorption feature was one close to 217.5 nm (2175 A). The normalized (averaged) spectrum of the whole sequence of biological materials and their degradation products absorption feature at 217.5 nm (2175 A) further support the contention that

  15. Matrix-Isolation Spectroscopy and Computational Studies of Reactive Organic Molecules of Relevance to Interstellar Space

    NASA Astrophysics Data System (ADS)

    Kopff, Laura A.; Kreifels, Terese A.; Schaffer, Christopher J.; Haenni, Benjamin C.; Esselman, Brian J.; McMahon, Robert J.

    2011-10-01

    Matrix isolation, the process of trapping a molecule in an inert gas at low temperature, provides a means for studying highly reactive intermediates, such as carbenes or radicals. Reactive species can be characterized by IR, UV-vis and/or EPR spectroscopy. Comparison of experimental and computed spectral data, as well as chemical reactivity, is used for structural assignment. Highly-unsaturated carbon chains are well known compounds in the interstellar medium (ISM). Detection of these molecules relies mostly on radioastronomy, making the detection of the linear HC2nH series difficult. The electronic structure changes from even carbon chain lengths (HC2nH) to odd chain lengths (HC2n+1H), changing from closed shell to open shell species. The odd series further alternate from a diradical character (HC3H) to a localized carbene (HC5H). This poster will present the synthesis and spectroscopy of the HC3H and HC7H species and derivatives. The study of arylcarbenes is vital to understanding the chemistry of carbon-rich environments, such as discharges, interstellar clouds, and circumstellar envelopes. The identification of small, sulfur containing molecules, and the identification of aromatics in the ISM make future thiophene and benzothiophene detections a real possibility. Studies on 2- and 3- diazomethyl substituted benzothiophenes are underway to assess their photochemical reactivity and potential for forming benzothiophene carbenes. Macrocylic polyynes are proposed to be involved in carbon condensation via the ring coalescence and annealing model to produce graphitic sheets or fullerenes. To simplify a complex system we are computationally studying the series of ethynyl-substituted cyclobutadienes and their possible involvement in the build-up of larger carbon containing molecules in the ISM.

  16. Scale-up considerations relevant to experimental studies of nuclear waste-package behavior

    SciTech Connect

    Coles, D.G.; Peters, R.D.

    1986-04-01

    Results from a study that investigated whether testing large-scale nuclear waste-package assemblages was technically warranted are reported. It was recognized that the majority of the investigations for predicting waste-package performance to date have relied primarily on laboratory-scale experimentation. However, methods for the successful extrapolation of the results from such experiments, both geometrically and over time, to actual repository conditions have not been well defined. Because a well-developed scaling technology exists in the chemical-engineering discipline, it was presupposed that much of this technology could be applicable to the prediction of waste-package performance. A review of existing literature documented numerous examples where a consideration of scaling technology was important. It was concluded that much of the existing scale-up technology is applicable to the prediction of waste-package performance for both size and time extrapolations and that conducting scale-up studies may be technically merited. However, the applicability for investigating the complex chemical interactions needs further development. It was recognized that the complexity of the system, and the long time periods involved, renders a completely theoretical approach to performance prediction almost hopeless. However, a theoretical and experimental study was defined for investigating heat and fluid flow. It was concluded that conducting scale-up modeling and experimentation for waste-package performance predictions is possible using existing technology. A sequential series of scaling studies, both theoretical and experimental, will be required to formulate size and time extrapolations of waste-package performance.

  17. Field studies of wildlife at Rocky Mountain Arsenal (RMA): Relevance to risk assessment

    SciTech Connect

    Nisbet, I.C.T.; Swain, W.R.; Star, I.

    1994-12-31

    Field studies of wildlife at contaminated sites can provide information about past and present effects, but are limited in spatial and temporal resolution. They cannot be used to predict future risks without utilizing risk assessment methodologies, including exposure-response relationships. RMA is unusual among Superfund sites in that its large size permits the existence of diverse wildlife populations in peripheral areas, despite high levels of contamination in central areas. Risk assessments conducted at RMA predict steep gradients in severity of effects from high in the central areas to low in peripheral areas. The population effects of such gradients will vary among species, depending on their exposure ranges and dispersal behavior. Effects on survival or reproduction in core areas may be partly or wholly offset by immigration from peripheral or offsite areas. Most field studies of wildlife populations at RMA have been conducted at scales inappropriate for ecological risk characterization, and have not been integrated with information on patterns of contamination or exposure. Hence, they do not provide much useful information to complement or modify the results of risk assessments. More focused field studies are needed to provide useful information on wildlife effects before and after remediation.

  18. Setup of a Biomedical Facility to Study Physiologically Relevant Flow-Structure Interactions

    NASA Astrophysics Data System (ADS)

    Mehdi, Faraz; Sheng, Jian

    2013-11-01

    The design and implementation of a closed loop biomedical facility to study arterial flows is presented. The facility has a test section of 25 inches, and is capable of generating both steady and pulsatile flows via a centrifugal and a dual piston pump respectively. The Reynolds and Womersley numbers occurring in major blood vessels can be matched. The working fluid is a solution of NaI that allows refractive index matching with both rigid glass and compliant polymer models to facilitate tomographic PIV and holographic PIV. The combination of these two techniques allows us to study both large scale flow features as well as flows very close to the wall. The polymer models can be made with different modulus of elasticity and can be pre-stressed using a 5-axis stage. Radially asymmetric patches can also be pre-fabricated and incorporated in the tube during the manufacturing process to simulate plaque formation in arteries. These tubes are doped with tracer particles allowing for the measurement of wall deformation. Preliminary flow data over rigid and compliant walls is presented. One of the aims of this study is to characterize the changes in flow as the compliancy of blood vessels change due to age or disease, and explore the fluid interactions with an evolving surface boundary.

  19. Relevance of behavioral and social models to the study of consumer energy decision making and behavior

    SciTech Connect

    Burns, B.A.

    1980-11-01

    This report reviews social and behavioral science models and techniques for their possible use in understanding and predicting consumer energy decision making and behaviors. A number of models and techniques have been developed that address different aspects of the decision process, use different theoretical bases and approaches, and have been aimed at different audiences. Three major areas of discussion were selected: (1) models of adaptation to social change, (2) decision making and choice, and (3) diffusion of innovation. Within these three areas, the contributions of psychologists, sociologists, economists, marketing researchers, and others were reviewed. Five primary components of the models were identified and compared. The components are: (1) situational characteristics, (2) product characteristics, (3) individual characteristics, (4) social influences, and (5) the interaction or decision rules. The explicit use of behavioral and social science models in energy decision-making and behavior studies has been limited. Examples are given of a small number of energy studies which applied and tested existing models in studying the adoption of energy conservation behaviors and technologies, and solar technology.

  20. Oxidative addition of methane and benzene C--H bonds to rhodium center: A DFT study

    NASA Astrophysics Data System (ADS)

    Bi, Siwei; Zhang, Zhenwei; Zhu, Shufen

    2006-11-01

    A density functional theory study on mechanisms of the oxidative addition of methane and benzene C-H bonds to the rhodium center containing Cp and PMe 3 ligands has been performed. Our calculated results confirm that the C-H bond cleavage from a sigma complex to a hydride alkyl complex is the rate-determining step. Compared with the case of methane C-H bond, the oxidative addition of benzene C-H bond is more favorable kinetically and thermodynamically. Stronger backdonation from metal center to the σ ∗ antibonding orbital of benzene C-H bond is responsible for the observations.

  1. Inverse Kinematics Studies of Intermediate-Energy Reactions Relevant for SEE and Medical Problems

    SciTech Connect

    Aichelin, J.; Bargholtz, Ch.; Geren, L.; Tegner, P.-E.; Zartova, I.; Blomgren, J.; Olsson, N.; Budzanowski, A.; Czech, B.; Skwirczynska, I.; Chubarov, M.; Lozhkin, O.; Murin, Yu.; Pljuschev, V.; Zubkov, M.; Ekstroem, C.; Kolozhvari, A.; Persson, H.; Westerberg, L.; Jakobsson, B.

    2005-05-24

    The lack of systematic experimental checks on the intermediate-energy nuclear model simulations of heavily ionizing recoils from nucleon-nucleus collisions -- critical inputs for the Single Event Effect analysis of microelectronics and dosimetry calculations including high-LET components in the cancer tumor radiation therapy -- has been a primary motivation for a new experiment planned at the CELSIUS nuclear storage ring of The Svedberg Laboratory, Uppsala, Sweden. Details of the experiment and the first results from a feasibility study are presented here.

  2. Neutron scattering studies of industry-relevant materials : connecting microscopic behavior to applied properties.

    SciTech Connect

    Loong, C.-K.

    1999-01-04

    Certain systems of oxides, nitrides and carbides have been recognized as the basic components of advanced materials for applications as engineering and electronic ceramics, catalysts, sensors, etc. under extreme environments. An understanding of the basic atomic and electronic properties of these systems will benefit enormously the industrial development, of new materials featuring tailored properties. We present an overview of neutron-scattering studies of the crystal phases, microstructure, phonon and magnetic excitations of key materials including rare-earth phosphates, phosphate glasses, nanostructured metal oxides, as well as silicon nitride and silicon carbide ceramics. A close collaboration among neutron-scattering experimentation, molecular-dynamics simulation and material synthesis is emphasized.

  3. Laboratory kinetic studies of OH and CO2 relevant to upper atmospheric radiation balance

    NASA Technical Reports Server (NTRS)

    Nelson, David D.; Zahniser, Mark S.; Kolb, Charles E.

    1994-01-01

    During the first year of this program, we have made considerable progress toward the measurement of the dipole moments of vibrationally excited OH radicals. Our primary accomplishments have been 1) the modification of the original slit jet spectrometer for the study of radical species and 2) the observation of infrared chemiluminescence from the vibrationally excited OH radicals formed in the H + ozone reaction in the supersonic jet. We are optimistic that we will soon observe OH* laser induced fluorescence in the jet. Modulation of this fluorescence with microwave radiation in an applied electric field will be the final step required for the precise determination of the vibrational dependence of the OH dipole moment.

  4. Establishment of HK-2 Cells as a Relevant Model to Study Tenofovir-Induced Cytotoxicity

    PubMed Central

    Murphy, Rachel A.; Stafford, Reagan M.; Petrasovits, Brooke A.; Boone, Megann A.; Valentovic, Monica A.

    2017-01-01

    Tenofovir (TFV) is an antiviral drug approved for treating Human Immunodeficiency Virus (HIV) and Hepatitis B. TFV is administered orally as the prodrug tenofovir disoproxil fumarate (TDF) which then is deesterified to the active drug TFV. TFV induces nephrotoxicity characterized by renal failure and Fanconi Syndrome. The mechanism of this toxicity remains unknown due to limited experimental models. This study investigated the cellular mechanism of cytotoxicity using a human renal proximal tubular epithelial cell line (HK-2). HK-2 cells were grown for 48 h followed by 24 to 72 h exposure to 0–28.8 μM TFV or vehicle, phosphate buffered saline (PBS). MTT (MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) and Trypan blue indicated that TFV diminished cell viability at 24–72 h. TFV decreased ATP levels at 72 h when compared to vehicle, reflecting mitochondrial dysfunction. TFV increased the oxidative stress biomarkers of protein carbonylation and 4-hydroxynonenol (4-HNE) adduct formation. Tumor necrosis factor alpha (TNFα) was released into the media following exposure to 14.5 and 28.8 μM TFV. Caspase 3 and 9 cleavage was induced by TFV compared to vehicle at 72 h. These studies show that HK-2 cells are a sensitive model for TFV cytotoxicity and suggest that mitochondrial stress and apoptosis occur in HK-2 cells treated with TFV. PMID:28257038

  5. The utilization of physisorption analyzer for studying the hygroscopic properties of atmospheric relevant particles.

    PubMed

    Ma, Qingxin; Liu, Yongchun; He, Hong

    2010-04-01

    The hygroscopic behavior of atmospheric aerosols has a significant effect on the global climate change. In this study, a physisorption analyzer was used to measure the water adsorption capacity of Al(2)O(3), NaCl, NH(4)NO(3), and (NH(4))(2)SO(4) particles at 273.6 K. Qualitative and quantitative information about water adsorption on these particles was obtained with changing the temperature and/or relative humidity (RH). Uptake of water on Al(2)O(3) showed a type-II BET adsorption isotherm with the monolayer formed at approximately 18% relative humidity (RH). The hygroscopic properties of NaCl, (NH(4))(2)SO(4), and NH(4)NO(3), including the deliquescence relative humidities (DRH), the temperature dependence of the DRH for NH(4)NO(3), and the growth factors of NaCl and (NH(4))(2)SO(4) were determined. All these results were in good agreement with the results obtained by other methods and/or theoretical prediction with a deviation less than 2%. For NaCl, the water adsorption amount increase rate exhibits three stages (<30% RH, approximately 30%-65% RH, and >65% RH) in the predeliquescence process and monolayer thin film water was formed at about 30% RH. It demonstrated that this instrument was practicable for studying the hygroscopic behavior of both soluble and insoluble but wettable atmospheric nonviolate aerosol particles.

  6. Establishment of HK-2 Cells as a Relevant Model to Study Tenofovir-Induced Cytotoxicity.

    PubMed

    Murphy, Rachel A; Stafford, Reagan M; Petrasovits, Brooke A; Boone, Megann A; Valentovic, Monica A

    2017-03-01

    Tenofovir (TFV) is an antiviral drug approved for treating Human Immunodeficiency Virus (HIV) and Hepatitis B. TFV is administered orally as the prodrug tenofovir disoproxil fumarate (TDF) which then is deesterified to the active drug TFV. TFV induces nephrotoxicity characterized by renal failure and Fanconi Syndrome. The mechanism of this toxicity remains unknown due to limited experimental models. This study investigated the cellular mechanism of cytotoxicity using a human renal proximal tubular epithelial cell line (HK-2). HK-2 cells were grown for 48 h followed by 24 to 72 h exposure to 0-28.8 μM TFV or vehicle, phosphate buffered saline (PBS). MTT (MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) and Trypan blue indicated that TFV diminished cell viability at 24-72 h. TFV decreased ATP levels at 72 h when compared to vehicle, reflecting mitochondrial dysfunction. TFV increased the oxidative stress biomarkers of protein carbonylation and 4-hydroxynonenol (4-HNE) adduct formation. Tumor necrosis factor alpha (TNFα) was released into the media following exposure to 14.5 and 28.8 μM TFV. Caspase 3 and 9 cleavage was induced by TFV compared to vehicle at 72 h. These studies show that HK-2 cells are a sensitive model for TFV cytotoxicity and suggest that mitochondrial stress and apoptosis occur in HK-2 cells treated with TFV.

  7. Computational Study of Collisions Between O(3P) and NO(2Pi) at Temperatures Relevant to the Hypersonic Flight Regime

    DTIC Science & Technology

    2014-10-29

    LIST DTIC/OCP 8725 John J. Kingman Rd, Suite 0944 Ft Belvoir, VA 22060-6218 1 cy AFRL /RVIL Kirtland AFB, NM 87117-5776 2 cys Official Record... AFRL -RV-PS- AFRL -RV-PS- TR-2015-0072 TR-2015-0072 COMPUTATIONAL STUDY OF COLLISIONS BETWEEN O(3P) AND NO(2Π) AT TEMPERATURES RELEVANT TO THE...UNLIMITED. AIR FORCE RESEARCH LABORATORY Space Vehicles Directorate 3550 Aberdeen Ave SE AIR FORCE MATERIEL COMMAND KIRTLAND AIR FORCE BASE, NM

  8. A synchrotron study of microstructure gradient in laser additively formed epitaxial Ni-based superalloy

    PubMed Central

    Xue, Jiawei; Zhang, Anfeng; Li, Yao; Qian, Dan; Wan, Jingchun; Qi, Baolu; Tamura, Nobumichi; Song, Zhongxiao; Chen, Kai

    2015-01-01

    Laser additive forming is considered to be one of the promising techniques to repair single crystal Ni-based superalloy parts to extend their life and reduce the cost. Preservation of the single crystalline nature and prevention of thermal mechanical failure are two of the most essential issues for the application of this technique. Here we employ synchrotron X-ray microdiffraction to evaluate the quality in terms of crystal orientation and defect distribution of a Ni-based superalloy DZ125L directly formed by a laser additive process rooted from a single crystalline substrate of the same material. We show that a disorientation gradient caused by a high density of geometrically necessary dislocations and resultant subgrains exists in the interfacial region between the epitaxial and stray grains. This creates a potential relationship of stray grain formation and defect accumulation. The observation offers new directions on the study of performance control and reliability of the laser additive manufactured superalloys. PMID:26446425

  9. A synchrotron study of microstructure gradient in laser additively formed epitaxial Ni-based superalloy

    SciTech Connect

    Xue, Jiawei; Zhang, Anfeng; Li, Yao; Qian, Dan; Wan, Jingchun; Qi, Baolu; Tamura, Nobumichi; Song, Zhongxiao; Chen, Kai

    2015-10-08

    Laser additive forming is considered to be one of the promising techniques to repair single crystal Ni-based superalloy parts to extend their life and reduce the cost. Preservation of the single crystalline nature and prevention of thermal mechanical failure are two of the most essential issues for the application of this technique. Here we employ synchrotron X-ray microdiffraction to evaluate the quality in terms of crystal orientation and defect distribution of a Ni-based superalloy DZ125L directly formed by a laser additive process rooted from a single crystalline substrate of the same material. We show that a disorientation gradient caused by a high density of geometrically necessary dislocations and resultant subgrains exists in the interfacial region between the epitaxial and stray grains. This creates a potential relationship of stray grain formation and defect accumulation. In conclusion, the observation offers new directions on the study of performance control and reliability of the laser additive manufactured superalloys.

  10. Fundamental Studies of Charge Migration and Delocalization Relevant to Solar Energy Conversion

    SciTech Connect

    Michael J. Therien

    2012-06-01

    This program aimed to understand the molecular-level principles by which complex chemical systems carry out photochemical charge separation, transport, and storage, and how these insights could impact the design of practical solar energy conversion and storage devices. Towards these goals, this program focused on: (1) carrying out fundamental mechanistic and transient dynamical studies of proton-coupled electron-transfer (PCET) reactions; (2) characterizing and interrogating via electron paramagnetic resonance (EPR) spectroscopic methods novel conjugated materials that feature large charge delocalization lengths; and (3) exploring excitation delocalization and migration, as well as polaron transport properties of meso-scale assemblies that are capable of segregating light-harvesting antennae, nanoscale wire-like conduction elements, and distinct oxidizing and reducing environments.

  11. Dynamical Studies of Chemical Reactions Relevant to the Local Atmosphere of the Orbiting Space Shuttle.

    DTIC Science & Technology

    1998-02-01

    Cartechini, P. Casavecchia, E.H. van Kleef, G.G. Volpi, F.J. Aoiz , L. Banares, D.W. Schwenke, T.C. Allison, S.L. Mielke, and D.G. Truhlar Dynamics of...F.J. Aoiz , L. Banares, D.W. Schwenke, T.C. Allison, S.L. Mielke, and D.G. Truhlar The dynamics of the reaction CI + H 2 (D2 ) -> HCI(DCl) + H(D): A...respect to the previous study by P. Casavecchia, R.J. Buss, S.J. Sibener, and Y.T. Lee, J. Chem. Phys. 1980). 2. A.J. Alexander, F.J. Aoiz , M. Brouard

  12. Relevance of aerosol size spectrum analysis as support to qualitative source apportionment studies.

    PubMed

    Manigrasso, M; Febo, A; Guglielmi, F; Ciambottini, V; Avino, P

    2012-11-01

    This work presents a diagnostic methodology in support to source apportionment studies to identify remote and local pollution sources. It is based on the temporal analysis of both PM size distributions and PM size fraction correlation along with natural radioactivity measurements as index of Planetary Boundary Layer dynamic. A correlation drop is indicative of changing aerosol sources. When this observation is coupled with decreasing level of natural radioactivity and increasing aerosol concentration, be it coarse or fine, it is indicative of the inflow of remote polluted air masses. The methodology defines in which size range operates the contribution of remote pollution sources. It was applied to two PM10 pollution episodes: the first involved the advection of coarse PM, the second entailed the inflow of two air masses, one transporting coarse dust and the other fine PM. Dust models and backward trajectories analysis confirmed such results, indicating the air mass provenience.

  13. Laboratory verification of submicron magnetite production in pseudotachylytes: relevance for paleointensity studies

    NASA Astrophysics Data System (ADS)

    Nakamura, Norihiro; Hirose, Takehiro; Borradaile, Graham J.

    2002-07-01

    Pseudotachylytes generally possess stable remanent magnetizations but the processes by which pseudotachylytes are magnetized remain poorly understood. Magnetic hysteresis and scanning electron microscope studies reveal that experimental frictional melting of granites produces dispersed submicron inclusions of weakly interacting pseudo-single-domain (PSD) magnetite, in artificial pseudotachylyte. The magnetite inclusions are absent in the undeformed granite protolith and result from oxidation of Fe in melt-susceptible mafic minerals during the melt-quenched event. The pseudotachylytes acquired a stable thermal remanence in fine-grained PSD magnetites during the rapid cooling of the melt, implying that fine-grained magnetite has the potential for paleointensity determinations of contemporaneous magnetic fields with co-seismic faulting in granitoids.

  14. Cancer Cytokines and the Relevance of 3D Cultures for Studying those Implicated in Human Cancers.

    PubMed

    Maddaly, Ravi; Subramaniyan, Aishwarya; Balasubramanian, Harini

    2017-03-06

    Cancers are complex conditions and involving several factors for oncogenesis and progression. Of the various factors influencing the physiology of cancers, cytokines are known to play significant roles as mediators of functions. Intricate cytokine networks have been identified in cancers and interest in cytokines associated with cancers has been gaining ground. Of late, some of these cytokines are even identified as potential targets for cancer therapy apart from a few others such as IL-6 being identified as markers for disease prognosis. Of the major contributors to cancer research, cancer cell lines occupy the top slot as the most widely used material in vitro. In vitro cell cultures have seen significant evolution by the introduction of 3 dimensional (3D) culture systems. 3D cell cultures are now widely accepted as excellent material for cancer research which surpasses the traditional monolayer cultures. Cancer research has benefitted from 3D cell cultures for understanding the various hallmarks of cancers. However, the potential of these culture systems are still unexploited for cancer cytokine research compared to the other aspects of cancers such as gene expression changes, drug-induced toxicity, morphology, angiogenesis and invasion. Considering the importance of cancer cytokines, 3D cell cultures can be better utilized in understanding their roles and functions. Some of the possibilities where 3D cell cultures can contribute to cancer cytokine research arise from the distinct morphology of the tumor spheroids, the extracellular matrix (ECM), and the spontaneous occurrence of nutrient and oxygen gradients. Also, the 3D culture models enable one to co-culture different types of cells as a simulation of in vivo conditions, enhancing their utility to study cancer cytokines. We review here the cancer associated cytokines the contributions of 3D cancer cell cultures for studying cancer cytokines. This article is protected by copyright. All rights reserved.

  15. Fine particles and coarse particles: concentration relationships relevant to epidemiologic studies.

    PubMed

    Wilson, W E; Suh, H H

    1997-12-01

    Fine particles and coarse particles are defined in terms of the modal structure of particle size distributions typically observed in the atmosphere. Differences between the various modes are discussed. The fractions of fine and coarse particles collected in specific size ranges, such as total suspended particulate matter (TSP), PM10, PM2.5, and PM(10-2.5), are shown. Correlations of 24-h concentrations of PM2.5, PM10, and PM(10-2.5) at the same site show that, in Philadelphia and St. Louis, PM2.5 is highly correlated with PM10 but poorly correlated with PM (10-2.5). Among sites distributed across these urban areas, the site-to-site correlations of 24-h PM concentrations are high for PM2.5 but not for PM(10-2.5). This indicates that a PM measurement at a central monitor can serve as a better indicator of the community-wide concentration of fine particles than of coarse particles. The fraction of ambient outdoor particles found suspended indoors is greater for fine particles than for coarse particles because of the difference in indoor lifetimes. Consideration of these relationships leads to the hypothesis that the statistical associations found between daily PM indicators and health outcomes may be the result of variations in the fine particle component of the atmospheric aerosol, not of variations in the coarse component. As a result, epidemiologic studies using PM10 or TSP may provide more useful information on the acute health effects of fine particles than coarse particles. Fine and coarse particles are separate classes of pollutants and should be measured separately in research and epidemiologic studies. PM2.5 and PM(10-2.5) are indicators or surrogates, but not measurements, of fine and coarse particles.

  16. Studies of levels of biogenic amines in meat samples in relation to the content of additives.

    PubMed

    Jastrzębska, Aneta; Kowalska, Sylwia; Szłyk, Edward

    2016-01-01

    The impact of meat additives on the concentration of biogenic amines and the quality of meat was studied. Fresh white and red meat samples were fortified with the following food additives: citric and lactic acids, disodium diphosphate, sodium nitrite, sodium metabisulphite, potassium sorbate, sodium chloride, ascorbic acid, α-tocopherol, propyl 3,4,5-trihydroxybenzoate (propyl gallate) and butylated hydroxyanisole. The content of spermine, spermidine, putrescine, cadaverine, histamine, tyramine, tryptamine and 2-phenylethylamine was determined by capillary isotachophoretic methods in meat samples (fresh and fortified) during four days of storage at 4°C. The results were applied to estimate the impact of the tested additives on the formation of biogenic amines in white and red meat. For all tested meats, sodium nitrite, sodium chloride and disodium diphosphate showed the best inhibition. However, cadaverine and putrescine were characterised by the biggest changes in concentration during the storage time of all the additives. Based on the presented data for the content of biogenic amines in meat samples analysed as a function of storage time and additives, we suggest that cadaverine and putrescine have a significant impact on meat quality.

  17. Summary of Previous Chamber or Controlled Anthrax Studies and Recommendations for Possible Additional Studies

    SciTech Connect

    Piepel, Gregory F.; Amidan, Brett G.; Morrow, Jayne B.

    2010-12-29

    This report and an associated Excel file(a) summarizes the investigations and results of previous chamber and controlled studies(b) to characterize the performance of methods for collecting, storing and/or transporting, extracting, and analyzing samples from surfaces contaminated by Bacillus anthracis (BA) or related simulants. This report and the Excel are the joint work of the Pacific Northwest National Laboratory (PNNL) and the National Institute of Standards and Technology (NIST) for the Department of Homeland Security, Science and Technology Directorate. The report was originally released as PNNL-SA-69338, Rev. 0 in November 2009 with limited distribution, but was subsequently cleared for release with unlimited distribution in this Rev. 1. Only minor changes were made to Rev. 0 to yield Rev. 1. A more substantial update (including summarizing data from other studies and more condensed summary tables of data) is underway

  18. Studies of biominerals relevant to the search for life on Mars.

    PubMed

    Blanco, Armando; D'Elia, Marcella; Licchelli, Domenico; Orofino, Vincenzo; Fonti, Sergio

    2006-12-01

    The evidence of the water erosion on Mars is particularly interesting since present climatic conditions are such that liquid water cannot exist at the surface. But, if water was present on the planet in the past, there may have been life, too. Since the discovery of carbonates on Mars also may have very important implications on the possibility that life developed there, we are studying minerals that can have biotic or abiotic origin: calcite (CaCO(3)) and aragonite, a metastable state of calcite.We have analysed biomineral aragonite, in the form of recent sea shells, as well as crystals of mineral aragonite. Infrared spectroscopy in the 2-25 mum wavelength range reveals that, after thermal processing, the biotic samples have a different spectral behaviour from the abiotic ones. As a result, it is possible to distinguish abiotic mineral aragonite from aragonite of recent biological origin.Obviously, if life existed in the past on the Red Planet, we could expect to find "ancient" biotic carbonates, which should therefore be investigated, in order to search for a way of discriminating them from abiotic minerals. For this reason, at the beginning we have considered samples of crushed fossil shells of aragonite composition. Afterwards, in order to take into account that fossilization processes almost always produce a transformation of metastable form (aragonite) into more stable form (calcite), we also studied samples of mineral calcite and different types of fossils completely transformed into calcite. All these biotic fossil samples show the same spectral behaviour as the fresh biotic material after thermal annealing at 485 degrees C. Instead, the calcite behaves like abiotic aragonite.Furthermore, it is known that seashells and other biominerals are formed through an intimate association of inorganic materials with organic macromolecules. The macromolecules control the nucleation, structure, morphology, crystal orientation and spatial confinement of the inorganic

  19. Studies of Biominerals Relevant to the Search for Life on Mars

    NASA Astrophysics Data System (ADS)

    Blanco, Armando; D'Elia, Marcella; Licchelli, Domenico; Orofino, Vincenzo; Fonti, Sergio

    2006-12-01

    The evidence of the water erosion on Mars is particularly interesting since present climatic conditions are such that liquid water cannot exist at the surface. But, if water was present on the planet in the past, there may have been life, too. Since the discovery of carbonates on Mars also may have very important implications on the possibility that life developed there, we are studying minerals that can have biotic or abiotic origin: calcite (CaCO3) and aragonite, a metastable state of calcite. We have analysed biomineral aragonite, in the form of recent sea shells, as well as crystals of mineral aragonite. Infrared spectroscopy in the 2 25 μm wavelength range reveals that, after thermal processing, the biotic samples have a different spectral behaviour from the abiotic ones. As a result, it is possible to distinguish abiotic mineral aragonite from aragonite of recent biological origin. Obviously, if life existed in the past on the Red Planet, we could expect to find “ancient” biotic carbonates, which should therefore be investigated, in order to search for a way of discriminating them from abiotic minerals. For this reason, at the beginning we have considered samples of crushed fossil shells of aragonite composition. Afterwards, in order to take into account that fossilization processes almost always produce a transformation of metastable form (aragonite) into more stable form (calcite), we also studied samples of mineral calcite and different types of fossils completely transformed into calcite. All these biotic fossil samples show the same spectral behaviour as the fresh biotic material after thermal annealing at 485°C. Instead, the calcite behaves like abiotic aragonite. Furthermore, it is known that seashells and other biominerals are formed through an intimate association of inorganic materials with organic macromolecules. The macromolecules control the nucleation, structure, morphology, crystal orientation and spatial confinement of the inorganic

  20. Enhanced Field Emission Studies on Niobium Surfaces Relevant to High Field Superconducting Radio-Frequency Devices

    SciTech Connect

    Wang, Tong

    2002-09-18

    Enhanced field emission (EFE) presents the main impediment to higher acceleration gradients in superconducting niobium (Nb) radiofrequency cavities for particle accelerators. The strength, number and sources of EFE sites strongly depend on surface preparation and handling. The main objective of this thesis project is to systematically investigate the sources of EFE from Nb, to evaluate the best available surface preparation techniques with respect to resulting field emission, and to establish an optimized process to minimize or eliminate EFE. To achieve these goals, a scanning field emission microscope (SFEM) was designed and built as an extension to an existing commercial scanning electron microscope (SEM). In the SFEM chamber of ultra high vacuum, a sample is moved laterally in a raster pattern under a high voltage anode tip for EFE detection and localization. The sample is then transferred under vacuum to the SEM chamber equipped with an energy-dispersive x-ray spectrometer for individual emitting site characterization. Compared to other systems built for similar purposes, this apparatus has low cost and maintenance, high operational flexibility, considerably bigger scan area, as well as reliable performance. EFE sources from planar Nb have been studied after various surface preparation, including chemical etching and electropolishing, combined with ultrasonic or high-pressure water rinse. Emitters have been identified, analyzed and the preparation process has been examined and improved based on EFE results. As a result, field-emission-free or near field-emission-free surfaces at ~140 MV/m have been consistently achieved with the above techniques. Characterization on the remaining emitters leads to the conclusion that no evidence of intrinsic emitters, i.e., no fundamental electric field limit induced by EFE, has been observed up to ~140 MV/m. Chemically etched and electropolished Nb are compared and no significant difference is observed up to ~140 MV/m. To

  1. Sand as a relevant fraction in geochemical studies in intertidal environments.

    PubMed

    Otero, X L; Huerta-Díaz, M A; De La Peña, S; Ferreira, T O

    2013-10-01

    Soil and sediment samples from several intertidal environment exposed to different types of contamination were studied to investigate the importance of grain size in relation to the capacity of the substrates to retain trace metals. The unfractionated samples (referred to as bulk samples) were separated into the following grain/size fractions: fine-coarse sand (2-0.100 mm), very fine sand (0.100-0.050 mm), silt (0.050-0.002 mm), and clay (0.002 mm). The sample into its fractions was carried out was in a glove box under high-purity N2 atmosphere in order to minimize any alterations to the samples. The bulk samples were characterized in terms of physicochemical properties such as pH, redox potential, and grain size. The total organic carbon (TOC), total sulfur (S), iron (Fe) pyrite, Fe, and manganese (Mn), and trace metals lead (Pb), mercury (Hg), chromium (Cr), and nickel (Ni) were analyzed in the bulk samples and in each fraction. The sand fractions were also examined by scanning electron microscopy (SEM). Comparisons of the above parameters were made between fractions and between each fraction and the corresponding bulk sample. The fine-coarse sand fraction contained high levels of the primary elements of the geochemical processes that occur in marine sedimentary environments such as TOC, total Fe, Mn, and S. The net concentrations of these four elements were higher in the fine-coarse sand fraction than in the very fine sand fraction and were similar to the net concentrations in the silt and clay fractions. Detailed SEM analysis of the sand coarse fraction revealed the presence of Fe and aluminum oxyhydroxide coatings in the oxic layers, whereas the framboidal pyrites and coatings observed in the anoxic layers were Fe sulfides. The presence of the various coatings explains why the trace metal concentrations in the sand fine-coarse fraction were similar to those in the clay fraction and higher than those in the very fine sand fraction. The present results

  2. Plans for Studies of (alpha,n) Reactions Relevant to Astrophysics via Inverse Reactions

    NASA Astrophysics Data System (ADS)

    Shima, T.; Nagai, Y.; Kii, T.; Kikuchi, T.; Baba, T.; Kobayashi, T.; Okazaki, F.

    1996-08-01

    (alpha,n) reactions in the keV energy region play important roles in astrophysical nucleosynthesis. In the primordial nucleosynthesis, it has been pointed out that a fluctuation of the baryon density distribution could be formed if the QCD phase transition from quark-gluon plasma to hadron gas occurred by first order. In that case the space was separated into the high density proton-rich zones and the low density neutron-rich ones, and in the neutron-rich zones nucleosynthesis could proceed beyond the mass gap at A = 8 via the reaction chains such as H-1(n,gamma)H-2(n,gamma)H-3(d,n)He-4(t,gamma)Li-7(n,gamma)Li-8(alpha,n)B- 11(n,ga mma)B-12(e(sup-)nu)C-12(n,gamma)C-13(n,gamma)C-14(n,gamma)C-15 ......, and so on. In the above nuclear reactions, the Li-8(alpha,n)B reaction plays quite a crucial role, because it can break through the mass gap at A = 8. (alpha,n) reactions of some light nuclei are also important as neutron sources for slow neutron capture process (s-process) of nucleosynthesis in stars. In low-mass and intermediate-mass (M < 10 Solar Mass) stars, neutrons are supposed to be supplied mainly by the C-13(alpha,n)O-16 reaction. On the other hand, the Ne-22(alpha,n)Mg-25 reaction is a candidate of the neutron source in massive stars with M > or = 10 Solar Mass. The contribution of the O-18(alpha,n)Ne-21 reaction to s-process in massive stars is still unknown. Since the temperatures of the above astrophysical sites correspond to the energy range of between a few ten and a few hundred keV, accurate data of the (alpha,n) reaction cross sections in the energy range are required for investigating nucleosynthesis. In order to measure these cross sections, not only direct (alpha,n) reactions but also inverse (n,alpha) reactions can be studied. In the following we would like to show experimental designs for studying several (alpha,n) reactions of astrophysical importance.

  3. Searching for a relevant definition of sarcopenia: results from the cross-sectional EPIDOS study

    PubMed Central

    Dupuy, Charlotte; Lauwers-Cances, Valérie; Guyonnet, Sophie; Gentil, Catherine; Abellan Van Kan, Gabor; Beauchet, Olivier; Schott, Anne-Marie; Vellas, Bruno; Rolland, Yves

    2015-01-01

    Background The diversity of definitions proposed for sarcopenia has been rarely tested in the same population, and so far, their clinical utilities for predicting physical difficulties could not be clearly understood. Our objective is to report the prevalence of sarcopenia and the characteristics of sarcopenic community-dwelling older women according to the different definitions of sarcopenia currently proposed. We also assessed these definitions for their incremental predictive value over currently standard predictors for some self-reported difficulties in physical function and knee extension strength. Methods Cross-sectional analysis included data from 3025 non-disabled women aged 75 years or older without previous history of hip fracture from the inclusion visit of the EPIDémiologie de l'OStéoporose study. A total body composition evaluation was available for 2725 women. Sarcopenia was defined using six different definitions of sarcopenia based on different muscle mass, gait speed, and grip strength cut-offs. Self-reported difficulties in physical function and knee extension strength were collected. Logistic regression and multiple linear regression models were built for each physical dysfunction, and the predictive capacity of sarcopenia (one model for each definition) was studied using the C-statistic, the net reclassification index, or adjusted R2. Results The estimated prevalence of sarcopenia ranged from 3.3–20.0%. Only 85 participants (3.1%) were identified having sarcopenia according to all definitions. All definitions were, to some degree, associated with self-reported difficulties in physical function and knee extension strength, but none improved the predictive ability of the self-reported difficulties in physical function. Conversely, all definitions accounted for a small but significant amount of explained variation for predicting knee extension strength. Conclusions Prevalence of sarcopenia varies widely depending on the definition adopted

  4. Climate-relevant properties of diesel particulate emissions: results from a piggyback study in Bangkok, Thailand.

    PubMed

    Subramanian, R; Winijkul, Ekbordin; Bond, Tami C; Thiansathit, Worrarat; Oanh, Nguyen Thi Kim; Paw-armart, Ittipol; Duleep, K G

    2009-06-01

    A "piggyback" approach is used to characterize aerosol emissions to obtain input for large-scale models of atmospheric transport. Particulate and gaseous emissions from diesel trucks, light-duty vehicles, and buses were measured by the Bangkok Pollution Control Department as part of the Developing Integrated Emissions Strategies for Existing Land Transport (DIESEL) project. We added filter-based measurements of carbonaceous composition, particulate light absorption, and water uptake. For 88 "normal" diesel vehicles (PM emission rate < 4.7 g/kg), our best estimate of the average PM2.5 emission rate is 2.2 +/- 0.5 g/kg, whereas for 15 high emitters, it is 8.4 +/- 1.9 g/kg. The effect of Euro standards on PM emission rates was apparent for heavy-duty vehicles, but not for light-duty vehicles. Carbonaceous composition appears relatively consistent, with particulate (artifact-corrected) OC at 17 +/- 1% and EC at 40 +/- 8% of PM for 103 pickups, vans, heavy-duty trucks and buses. The median absorption cross-section for EC is 10.5 m2/g at 532 nm. The history of average emission rate and chemical composition during the project suggests that about 25 vehicles can provide a regional PM emission rate for normal vehicles. Other studies such as remote sensing measurements will be required to estimate the important contribution of high-emitting vehicles.

  5. Clinical proteomic biomarkers: relevant issues on study design & technical considerations in biomarker development

    PubMed Central

    2014-01-01

    Biomarker research is continuously expanding in the field of clinical proteomics. A combination of different proteomic–based methodologies can be applied depending on the specific clinical context of use. Moreover, current advancements in proteomic analytical platforms are leading to an expansion of biomarker candidates that can be identified. Specifically, mass spectrometric techniques could provide highly valuable tools for biomarker research. Ideally, these advances could provide with biomarkers that are clinically applicable for disease diagnosis and/ or prognosis. Unfortunately, in general the biomarker candidates fail to be implemented in clinical decision making. To improve on this current situation, a well-defined study design has to be established driven by a clear clinical need, while several checkpoints between the different phases of discovery, verification and validation have to be passed in order to increase the probability of establishing valid biomarkers. In this review, we summarize the technical proteomic platforms that are available along the different stages in the biomarker discovery pipeline, exemplified by clinical applications in the field of bladder cancer biomarker research. PMID:24679154

  6. Studying counterstreaming high velocity plasma flows relevant to astrophysical collisionless shock

    NASA Astrophysics Data System (ADS)

    Ross, James Steven; Amendt, Peter; Divol, Laurent; Pollock, Brad; Remington, Bruce; Ryutov, Dmitri; rozmus, Wojciech; Turnbull, David; Froula, Dustin; morita, taichi; Sakawa, Youichi; Takabe, Hideke; Drake, R. Paul; Kuranz, Carolyn C.; Gregori, Gianluca; Meinecke, Jena; Koenig, Michel; Spitkovsky, Anatoly; Park, Hye-Sook

    2015-08-01

    In a broad range of low-density astrophysical plasmas the flow has a high Mach number, making the ion-ion collisional mean free path very large compared to the scale lengths of various observed astrophysical shocks. These shocks are believed to be “collisionless,” driven by plasma instabilities and self-generated magnetic fields. A series of experiments at the NIF and Omega laser facilities is underway to study the formation of collisionless shocks under scaled laboratory conditions, using high velocity counterstreaming and interpenetrating plasma flows. Double CH2, and CH/CD planar foils have been irradiated with a laser intensity of ~1016 W/cm2. The laser-ablated plasma between the two foils was characterized using a suite of diagnostics, including Thomson scattering and x-ray radiography. On the Omega laser facility clear interpenetration and instability growth are observed, although our experimental conditions reached only ~50 ion skin depths (c/wpi) and were insufficient to fully form a collisionless shock. Initial NIF experimental results using 50x more laser energy than the Omega experiments will be presented.

  7. Clinical proteomic biomarkers: relevant issues on study design & technical considerations in biomarker development.

    PubMed

    Frantzi, Maria; Bhat, Akshay; Latosinska, Agnieszka

    2014-03-29

    Biomarker research is continuously expanding in the field of clinical proteomics. A combination of different proteomic-based methodologies can be applied depending on the specific clinical context of use. Moreover, current advancements in proteomic analytical platforms are leading to an expansion of biomarker candidates that can be identified. Specifically, mass spectrometric techniques could provide highly valuable tools for biomarker research. Ideally, these advances could provide with biomarkers that are clinically applicable for disease diagnosis and/ or prognosis. Unfortunately, in general the biomarker candidates fail to be implemented in clinical decision making. To improve on this current situation, a well-defined study design has to be established driven by a clear clinical need, while several checkpoints between the different phases of discovery, verification and validation have to be passed in order to increase the probability of establishing valid biomarkers. In this review, we summarize the technical proteomic platforms that are available along the different stages in the biomarker discovery pipeline, exemplified by clinical applications in the field of bladder cancer biomarker research.

  8. [Study of "The Sūitra of the tranquilization of hemorrhoids" and other relevant material].

    PubMed

    Yamanaka, Yukio; Yamashita, Tsutomu; Akahane, Ritsu; Muroya, Yasutaka

    2011-09-01

    The present paper focuses primarily on a philological and historical study of the Arśapraśamanisūtra ("The Sütra of the tranquilization of hemorrhoids"). This Sūtra is one of the Buddhist scriptures that are characterized by the magico-religious treatment of various diseases, especially by means of "healing spells" (skt. dhāranī or mantra), as shown by the preliminary survey in our previous paper "The Tradition of healing with magical spells as seen in Buddhist texts", Journal of the Japan Society of Medical History 55/1 (2009), 77-96. The original text of the Arśapraśamanisūtra, most probably written in Sanskrit, is lost whereas its Chinese and Tibetan translations have survived. After an introductory summary, we provide critically edited texts of the Tibetan and Chinese translations accompanied by their Japanese translations with critical notes and annotations. In particular, the Tibetan translation presented here has been critically edited for the first time on the basis of collation of the five editions of the Tibetan Buddhist Canon. In our next paper we will analyze the descriptions of hemorrhoids as found in the Sūtra in comparison with those illustrated in classical Ayurveda literature. And we will also offer further observations about the methods and principles for the treatment and healing of hemorrhoid that are attested in Buddhist scriptures.

  9. Theoretical study of the formation of naphthalene from the radical/π-bond addition between single-ring aromatic hydrocarbons.

    PubMed

    Comandini, Andrea; Brezinsky, Kenneth

    2011-06-09

    The experimental investigations performed in the 1960s on the o-benzyne + benzene reaction as well as the more recent studies on reactions involving π-electrons highlight the importance of π-bonding for different combustion processes related to PAH's and soot formation. In the present investigation radical/π-bond addition reactions between single-ring aromatic compounds have been proposed and computationally investigated as possible pathways for the formation of two-ring fused compounds, such as naphthalene, which serve as precursors to soot formation. The computationally generated optimized structures for the stationary points were obtained with uB3LYP/6-311+G(d,p) calculations, while the energies of the optimized complexes were refined using the uCCSD(T) method and the cc-pVDZ basis set. The computations have addressed the relevance of a number of radical/π-bond addition reactions including the singlet benzene + o-benzyne reaction, which leads to formation of naphthalene and acetylene through fragmentation of the benzobicyclo[2,2,2]octatriene intermediate. For this reaction, the high-pressure limit rate constants for the individual elementary reactions involved in the overall process were evaluated using transition state theory analysis. Other radical/π-bond addition reactions studied were between benzene and triplet o-benzyne, between benzene and phenyl radical, and between phenyl radicals, for all of which potential energy surfaces were produced. On the basis of the results of these reaction studies, it was found necessary to propose and subsequently confirm additional, alternative pathways for the formation of the types of PAH compounds found in combustion systems. The potential energy surface for one reaction in particular, the phenyl + phenyl addition, is shown to contain a low-energy channel leading to formation of naphthalene that is energetically comparable to the other examined conventional pathways leading to formation of biphenyl compounds. This

  10. Studies on in situ particulate reinforced tin-silver composite solders relevant to thermomechanical fatigue issues

    NASA Astrophysics Data System (ADS)

    Choi, Sunglak

    2001-07-01

    Global pressure based on environmental and health concerns regarding the use of Pb-bearing solder has forced the electronics industry to develop Pb-free alternative solders. Eutectic Sn-Ag solder has received much attention as a potential Pb-free candidate to replace Sn-Pb solder. Since introduction of surface mount technology, packaging density increased and the electronic devices became smaller. As a result, solders in electronic modules are forced to function as a mechanical connection as well as electrical contact. Solders are also exposed to very harsh service conditions such as automotive under-the-hood and aerospace applications. Solder joints experience thermomechanical fatigue, i.e. interaction of fatigue and creep, during thermal cycling due to temperature fluctuation in service conditions. Microstructural study on thermomechanical fatigue of the actual eutectic Sn-Ag and Sn-4Ag-0.5Cu solder joints was performed to better understand deformation and damage accumulation occurring during service. Incorporation of reinforcements has been pursued to improve the mechanical and particularly thermomechanical behavior of solders, and their service temperature capability. In-situ Sn-Ag composite solders were developed by incorporating Cu 6Sn5, Ni3Sn4, and FeSn2 particulate reinforcements in the eutectic Sn-Ag solder in an effort to enhance thermomechanical fatigue resistance. In-situ composite solders were investigated on the growth of interfacial intermetallic layer between solder and Cu substrate growth and creep properties. Solder joints exhibited significant deformation and damage on free surface and interior regions during thermomechanical fatigue. Cracks initiated on the free surface of the solder joints and propagated toward interior regions near the substrate of the solder joint. Crack grew along Sn grain boundaries by grain boundary sliding. There was significant residual stress within the solder joint causing more damage. Presence of small amount of Cu

  11. Spectroscopic Studies of the H_3^+ + H_2 Reaction at Astrophysically Relevant Temperatures

    NASA Astrophysics Data System (ADS)

    Tom, Brian A.; McGuire, Brett A.; Moore, Lauren E.; Wood, Thomas J.; McCall, Benjamin J.

    2009-06-01

    H_3^+ is the key precursor to ion chemistry in the interstellar medium. It has been employed as an astrophysical probe of conditions of temperature and density due to its ubiquity in a variety of environments. The distribution of ortho- and para- spin modifications of H_3^+ is particularly interesting in this regard. Consequently, it is important to understand the pathways through which changes to the H_3^+ spin distribution can occur. One possible pathway is the H_3^+ + H_2 → H_2 + H_3^+ reaction, which proceeds by proton hop and proton exchange and is governed by the conservation of nuclear spin. Cordonnier et al. studies this reaction at high temperature in a pulsed hollow cathode cell, but to facilitate the understanding of astronomical observations, we need lower temperature measurements. Recently, we have constructed a liquid nitrogen-cooled hollow cathode discharge source and coupled it with multipass absorption spectroscopy to measure the ortho:para ratio of H_3^+ in plasmas at a variety of para-H_2 enrichment levels at ˜160 K. Previously, we have reported experimental measurements of the branching ratio between proton hop and exchange in a hydrogenic plasma at ˜80 K. Together, these experiments have allowed us to explore the temperature dependence of this branching ratio and provide valuable information for the interpretation of astronomical observations. [1] M. Cordonnier et al., J Chem Phys, 113, 3181 (2000) [2] B. A. Tom, M. B. Wiczer, A. A. Mills, K. N. Crabtree, and B. J. McCall, ``Observation of nuclear spin selection rules in supersonically expanding plasmas containing H_3^+,'' 63rd International Symposium on Molecular Spectroscopy (2008).

  12. Low-temperature Kinetic Studies of OH Radical Reactions Relevant to Planetary Atmospheres

    NASA Astrophysics Data System (ADS)

    Townsend, T. M.; Antiñolo, M.; Ballesteros, B.; Jimenez, E.; Canosa, A.

    2011-05-01

    In the solar system, the temperature (T) of the atmosphere of giant planets or their satellites is only several tens of Kelvin (K). The temperature of the tropopause of Titan (satellite of Saturn) and the surface of Mars is 70 K and 210 K, respectively. In the Earth's atmosphere, T decreases from 298 K (surface) to 210 K close to the T-inversion region (tropopause). The principal oxidants in the Earth's lower atmosphere are ozone, the hydroxyl (OH) radical and hydrogen peroxide. A number of critical atmospheric chemical problems depend on the Earth's oxidising capacity, which is essentially the global burden of these oxidants. In the interstellar clouds and circumstellar envelopes, OH radicals have also been detected. As the chemistry of atmospheres is highly influenced by temperature, the knowledge of the T-dependence of the rate coefficients for OH-reactions (k) is the key to understanding the underlying molecular mechanisms. In general, these reactions take place on a short temporal scale. Therefore, a detection technique with high temporal resolution is required. Measurements of k at low temperatures can be achieved by maintaining a thermalised environment using either cryogenic cooling (T>200 K) or supersonic gas expansion with a Laval nozzle (several tens of K). The pulsed laser photolysis technique coupled with laser induced fluorescence detection has been widely used in our laboratory to determine the rate coefficients of OH-reactions with different volatile organic compounds, such as alcohols (1), saturated and unsaturated aliphatic aldehydes (2), linear ketones (3), as a function of temperature (260 350 K). An experimental system based on the CRESU (Cinetique de Reaction en Ecoulement Supersonique Uniforme or Reaction Kinetics in a Uniform Supersonic Flow) technique is currently under construction. This technique will allow the performance of kinetic studies of OH-reactions of astrophysical interest at temperatures lower than 200 K.

  13. Laboratory Kinetic Studies of OH and CO2 Relevant to Upper Atmospheric Radiation Balance

    NASA Technical Reports Server (NTRS)

    Nelson, David D.; Villalta, Peter; Zahniser, Mark S.; Kolb, Charles E.

    1997-01-01

    The purpose of this project was to quantify the rates of two processes which are crucial to our understanding of radiative energy balance in the upper atmosphere. The first process is radiative emission from vibrationally hot OH radicals following the H + O3 reaction in the upper mesosphere. The importance of this process depends strongly on the OH radiative emission coefficients. Our goal was to measure the OH permanent dipole moment in excited vibrational states and to use these measurements to construct an improved OH dipole moment function and improved radiative emission coefficients. Significant progress was made on these experiments including the construction of a supersonic jet source for vibrationally excited OH radicals. Unfortunately, our efforts to transport the OH radicals into a second lower pressure vacuum chamber were not successful, and we were unable to make improved dipole moment measurements for OH. The second key kinetic process which we attempted to quantify during this project is the rate of relaxation of bend-excited CO2 by oxygen atoms. Since excitation of the bending vibrational mode of CO2 is the major cooling mechanism in the upper mesosphere/lower thermosphere, the cooling rate of this region depends crucially on the rate of energy transfer out of this state. It is believed that the most efficient transfer mechanism is via atomic oxygen but the rate for this process has not been directly measured in the laboratory at appropriate temperatures and even the room temperature rate remains controversial. We attempted to directly measure the relaxation rate Of CO2 (010) by oxygen atoms using the discharge flow technique. This experiment was set up at Aerodyne Research. Again, significant progress was achieved in this experiment. A hot CO2 source was set up, bend excited CO2 was detected and the rate of relaxation of bend excited CO2 by He atoms was measured. Unfortunately, the project ran out of time before the oxygen atom kinetic studies could

  14. Relevance of multiple spatial scales in habitat models: A case study with amphibians and grasshoppers

    NASA Astrophysics Data System (ADS)

    Altmoos, Michael; Henle, Klaus

    2010-11-01

    Habitat models for animal species are important tools in conservation planning. We assessed the need to consider several scales in a case study for three amphibian and two grasshopper species in the post-mining landscapes near Leipzig (Germany). The two species groups were selected because habitat analyses for grasshoppers are usually conducted on one scale only whereas amphibians are thought to depend on more than one spatial scale. First, we analysed how the preference to single habitat variables changed across nested scales. Most environmental variables were only significant for a habitat model on one or two scales, with the smallest scale being particularly important. On larger scales, other variables became significant, which cannot be recognized on lower scales. Similar preferences across scales occurred in only 13 out of 79 cases and in 3 out of 79 cases the preference and avoidance for the same variable were even reversed among scales. Second, we developed habitat models by using a logistic regression on every scale and for all combinations of scales and analysed how the quality of habitat models changed with the scales considered. To achieve a sufficient accuracy of the habitat models with a minimum number of variables, at least two scales were required for all species except for Bufo viridis, for which a single scale, the microscale, was sufficient. Only for the European tree frog ( Hyla arborea), at least three scales were required. The results indicate that the quality of habitat models increases with the number of surveyed variables and with the number of scales, but costs increase too. Searching for simplifications in multi-scaled habitat models, we suggest that 2 or 3 scales should be a suitable trade-off, when attempting to define a suitable microscale.

  15. Geotechnical studies relevant to the containment of underground nuclear explosions at the Nevada Test Site

    SciTech Connect

    Heuze, F.E.

    1982-05-01

    The Department of Energy and the Department of Defense are actively pursuing a program of nuclear weapons testing by underground explosions at the Nevada Test Site (NTS). Over the past 11 years, scores of tests have been conducted and the safety record is very good. In the short run, emphasis is put on preventing the release of radioactive materials into the atmosphere. In the long run, the subsidence and collapse of the ground above the nuclear cavities also are matters of interest. Currently, estimation of containment is based mostly on empiricism derived from extensive experience and on a combination of physical/mechanical testing and numerical modeling. When measured directly, the mechanical material properties are obtained from short-term laboratory tests on small, conventional samples. This practice does not determine the large effects of scale and time on measured stiffnesses and strengths of geological materials. Because of the limited data base of properties and in situ conditions, the input to otherwise fairly sophisticated computer programs is subject to several simplifying assumptions; some of them can have a nonconservative impact on the calculated results. As for the long-term, subsidence and collapse phenomena simply have not been studied to any significant degree. This report examines the geomechanical aspects of procedures currently used to estimate containment of undergroung explosions at NTS. Based on this examination, it is concluded that state-of-the-art geological engineering practice in the areas of field testing, large scale laboratory measurements, and numerical modeling can be drawn upon to complement the current approach.

  16. An In Vitro Spinal Cord–Hindlimb Preparation for Studying Behaviorally Relevant Rat Locomotor Function

    PubMed Central

    Hayes, Heather Brant; Chang, Young-Hui; Hochman, Shawn

    2009-01-01

    Although the spinal cord contains the pattern-generating circuitry for producing locomotion, sensory feedback reinforces and refines the spatiotemporal features of motor output to match environmental demands. In vitro preparations, such as the isolated rodent spinal cord, offer many advantages for investigating locomotor circuitry, but they lack the natural afferent feedback provided by ongoing locomotor movements. We developed a novel preparation consisting of an isolated in vitro neonatal rat spinal cord oriented dorsal-up with intact hindlimbs free to step on a custom-built treadmill. This preparation combines the neural accessibility of in vitro preparations with the modulatory influence of sensory feedback from physiological hindlimb movement. Locomotion induced by N-methyl d-aspartate and serotonin showed kinematics similar to that of normal adult rat locomotion. Changing orientation and ground interaction (dorsal-up locomotion vs ventral-up air-stepping) resulted in significant kinematic and electromyographic changes that were comparable to those reported under similar mechanical conditions in vivo. We then used two mechanosensory perturbations to demonstrate the influence of sensory feedback on in vitro motor output patterns. First, swing assistive forces induced more regular, robust muscle activation patterns. Second, altering treadmill speed induced corresponding changes in stride frequency, confirming that changes in sensory feedback can alter stride timing in vitro. In summary, intact hindlimbs in vitro can generate behaviorally appropriate locomotor kinematics and responses to sensory perturbations. Future studies combining the neural and chemical accessibility of the in vitro spinal cord with the influence of behaviorally appropriate hindlimb movements will provide further insight into the operation of spinal motor pattern-generating circuits. PMID:19073815

  17. In silico study of amyloid beta-protein folding relevant to Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Lam Ng, Alfonso Ramon

    Amyloid beta-protein (Abeta) folding is the initial step in the formation of the early toxic Abeta assemblies that are critically linked to Alzheimer's disease (AD). Abeta exists in two main alloforms, Abeta40 and Abeta42, composed of 40 and 42 residues, respectively. Abeta42 aggregates faster, forms more toxic assemblies, and is linked more strongly to AD. Two amino acids of Abeta42, I41 and A42, profoundly affect the behavior of Abeta40 and Abeta42. To examine why this happens, I study Abeta40 and Abeta42 folding using discrete molecular dynamics and a four-bead protein model with backbone hydrogen bonding and residue-specific effective hydropathic and electrostatic interactions. In particular, I explore a range of values of the hydropathic (EHP) and electrostatic (ECH) potential energies. For each peptide, I create a hundred different initial conformations for each set of parameters (EHP,E CH). I investigate the Abeta40 and Abeta42 monomer folding in a wide temperature range and quantify the folded structures by calculating the secondary structure propensities and the intramolecular contact maps. For each set of parameters (EHP,ECH), I calculate an average beta-strand secondary structure propensity in the Abeta40 and Abeta42 monomers as a function of temperature. I compare these simulated results with experimental circular dichroism measurements and estimate the model physiological temperature and the model parameters (E HP,ECH) that best fit the experimental conditions. The results show that in the temperature range [278K,350K], the average beta-strand in Abeta42 is larger than that of Abeta40, which is in agreement with experiments. The model predicts that the average beta-strand propensity should decrease for T>350K. At low temperatures, both Abeta40 and Abeta42 adopt a predominantly collapsed-coil conformation with small amounts of an beta-helical secondary structure (<1%). At high temperatures, beta-strand rich structures are more prominent (19%). Also, the

  18. Relevant prognostic factors in gastric cancer: ten-year results of the German Gastric Cancer Study.

    PubMed Central

    Siewert, J R; Böttcher, K; Stein, H J; Roder, J D

    1998-01-01

    OBJECTIVE: In 1986 a prospective multicenter observation trial in patients with resected gastric cancer was initiated in Germany. An analysis of prognostic factors based on the 10-year survival data is now presented. PATIENTS AND METHODS: A total of 1654 patients treated for gastric cancer between 1986 and 1989 at 19 centers in Germany and Austria were included. The resected specimen were evaluated histopathologically according to a standardized protocol. The extent of lymphadenectomy was classified after surgery based on the number of removed lymph nodes on histopathologic assessment (25 or fewer removed nodes, D1 or standard lymphadenectomy; >25 removed nodes, D2 or extended lymphadenectomy). Endpoint of the study was death. Follow-up is complete for 97% of the included patients (median follow-up of the surviving patients is 8.4 years). Prognostic factors were assessed by multivariate analysis. RESULTS: A complete macroscopic and microscopic tumor resection (R0 resection according to the UICC 1997) could be achieved in 1182 of the 1654 patients (71.5%). The calculated 10-year survival rate in the entire patient population was 26.3% +/- 4.7%; it was 36.1% +/- 1.6% after an R0 resection. In the total patient population there was an independent prognostic effect of the ratio between invaded and removed lymph nodes, the residual tumor (R) category, the pT category, the presence of postsurgical complications, and the presence of distant metastases. Multivariate analysis in the subgroup of patients who had a UICC R0 resection confirmed the nodal status, the pT category, and the presence of postsurgical complications as the major independent prognostic factors. The extent of lymph node dissection had a significant and independent effect on the 10-year survival rate in patients with stage II tumors. This effect was present in the subgroups with (pT2N1) and without (pT3N0) lymph node metastases on standard histopathologic assessment. The beneficial effect of extended

  19. Using epidemiology to regulate food additives: saccharin case-control studies.

    PubMed

    Cordle, F; Miller, S A

    1984-01-01

    The increasing use of nonnutritive sweeteners and the widely publicized 1969 ban on cyclamate led to additional investigations in rodents of the carcinogenic potential of saccharin. Preliminary results of a long-term feeding study indicated formation of bladder tumors in rodents, and collective experimental evidence has demonstrated that high doses of the synthetic sweetener saccharin can cause bladder cancer in rodents. Based on the results of that and other rodent studies indicating an increased risk of bladder cancer associated with saccharin, the Commissioner of the Food and Drug Administration announced the agency's intention to propose a ban on saccharin. This intention was made known in April 1977 under the Delaney Clause of the Food, Drug, and Cosmetic Act. The clause essentially states that no additive shall be deemed safe if it is found to induce cancer in man or animals, or if it is found, after tests appropriate for the evaluation of the safety of food additives, to induce cancer in man or animals. Also in 1977, a group of epidemiologists began to assess the available epidemiologic information to determine the potential human risk. This report describes the assessment of several human epidemiologic studies available then and the results of more recent epidemiologic studies.

  20. A kinetic study of struvite precipitation recycling technology with NaOH/Mg(OH)2 addition.

    PubMed

    Yu, Rongtai; Ren, Hongqiang; Wang, Yanru; Ding, Lili; Geng, Jingji; Xu, Ke; Zhang, Yan

    2013-09-01

    Struvite precipitation recycling technology is received wide attention in removal ammonium and phosphate out of wastewater. While past study focused on process efficiency, and less on kinetics. The kinetic study is essential for the design and optimization in the application of struvite precipitation recycling technology. The kinetics of struvite with NaOH/Mg(OH)2 addition were studied by thermogravimetry analysis with three rates (5, 10, 20 °C/min), using Friedman method and Ozawa-Flynn-Wall method, respectively. Degradation process of struvite with NaOH/Mg(OH)2 addition was three steps. The stripping of ammonia from struvite was mainly occurred at the first step. In the first step, the activation energy was about 70 kJ/mol, which has gradually declined as the reaction progress. By model fitting studies, the proper mechanism function for struvite decomposition process with NaOH/Mg(OH)2 addition was revealed. The mechanism function was f(α)=α(α)-(1-α)(n), a Prout-Tompkins nth order (Bna) model.

  1. Accelerator-Based Studies of Heavy Ion Interactions Relevant to Space Biomedicine

    NASA Technical Reports Server (NTRS)

    Miller, J.; Heilbronn, L.; Zeitlin, C.

    1999-01-01

    Alternating Gradient Synchrotron at Brookhaven National Laboratory (BNL AGS) and the Heavy Ion Medical Accelerator (HIMAC) in Chiba, Japan. Until fairly recently most of these experiments were done to investigate fundamental problems in nuclear physics, but with the increasing interest in heavy charged particles on the part of the space flight, radiobiology and radiotherapy communities, an increasing number of experiments are being directed at these areas. Some of these measurements are discussed in references therein. Over the past several years, our group has taken cross section and fluence data at the AGS and HIMAC for several incident beams with nuclear charge, Z, between 6 and 26 at energies between 290 and 1050 MeV/nucleon. Iron (Z = 26) has been studied most extensively, since it is the heaviest ion present in significant numbers in the GCR. Targets have included tissue-equivalent and proposed shielding materials, as well as a variety of elemental targets for cross section measurements. Most of the data were taken along the beam axis, but measurements have been made off-axis, as well. Here we present selected data and briefly discuss some implications for spacecraft and planetary habitat design.

  2. Synthesis and thermal studies of boron-containing heterosiloxanes, and their relevance to ceramic formation

    NASA Astrophysics Data System (ADS)

    Behebehani, Haider S. J.

    -heptasiloxane-l,6,7-triol, [(c-C6H11)7Si7O9(OH)3], were prepared by controlled hydrolysis of cyclohexyltrichlorosilane. The triol was used to synthesise a boron containing silsesquioxane, [(c-C6H1])7Si7O12B]2, by reaction with BI3. Thermolysis of c-Cy6Si6O9 up to 1700C under an inert atmosphere forms crystalline silica, whereas under similar conditions (Ph2SiO)n (where n = 3 or 4) volatilises. For comparative purposes a phenylmethylsilane-dimethylsilane copolymer was thermolysed under similar conditions in order to prepare silicon carbide from an oxygen free polymeric source. Compound 3, Ph2(HO)SiOSi(Ph2)OSi(OH)Ph2, compound 6, c-Cy6Si6O9, compound 16, PhB(Ph3SiO)2 and compound 19 Me2Si(PhBNH)2NH, were all characterised for the first time by single crystal x-ray diffraction studies, and their main structural features were discussed in relation to their chemical reactivity.

  3. Study of asphalt/asphaltene precipitation during addition of solvents to West Sak crude

    SciTech Connect

    Jiang, J.C.; Patil, S.L.; Kamath, V.A. )

    1990-07-01

    In this study, experimental data on the amount of asphalt and asphaltene precipitation due to addition of solvents to West Sak crude were gathered. The first set of tests were conducted for two types of West Sak stock tank oils. Solvents used include: ethane, carbon dioxide, propane, n-butane, n-pentane, n-heptane, Prudhoe Bay natural gas (PBG) and natural gas liquids (NGL). Effect of solvent to oil dilution ratio on the amount of precipitation was studied. Alteration of crude oil composition due to asphalt precipitation was measured using gas-liquid chromatography. A second set of experiments were conducted to measure asphaltene precipitation due to addition of CO{sub 2} to live (recombined) West Sak crude.

  4. Study on Co-doped ZnO comparatively by first-principles calculations and relevant experiments

    NASA Astrophysics Data System (ADS)

    Su, Y. L.; Zhang, Q. Y.; Zhou, N.; Ma, C. Y.; Liu, X. Z.; Zhao, J. J.

    2017-01-01

    Co-doped ZnO was studied using first-principles methods with comparison to experimental results taken from epitaxial Zn1-xCoxO (x 0.05) films. Density of Co2+ ions was determined using absorption spectra for the first time, and then a definite correlation between metallic Co clusters and the magnetism of the ZnCoO films was proved and the average number of Co atoms in the metallic Co clusters was estimated to be less than 200 using a superparamagnetic model. First-principles calculations of ZnCoO alloys and the relevant problems were discussed by comparing the electronic structures with absorption spectra and the results calculated by Tanabe-Sugano theory. U correction was proved to be necessary for calculating the band-gap energy of ZnCoO alloys, but other optical properties related to Co2+ ions are incorrect and the conclusion for magnetic properties is ambiguous due to uncertainty of the calculated highly localized states, which are in pressing for solution in study of material properties relevant to electronic structure.

  5. A simple, inexpensive, and field-relevant microcosm tidal simulator for use in marsh macrophyte studies1

    PubMed Central

    MacTavish, Rachel M.; Cohen, Risa A.

    2014-01-01

    • Premise of the study: A microcosm unit with tidal simulation was developed to address the challenge of maintaining ecologically relevant tidal regimes while performing controlled greenhouse experiments on smooth cordgrass, Spartina alterniflora. • Methods and Results: We designed a simple, inexpensive, easily replicated microcosm unit with tidal simulation and tested whether S. alterniflora growth in microcosms with tidal simulation was similar to that of tidally influenced plants in the field on Sapelo Island, Georgia. After three months of exposure to either natural or simulated tidal treatment, plants in microcosms receiving tidal simulation had similar stem density, height, and above- and belowground biomass to plants in field plots. • Conclusions: The tidal simulator developed may provide an inexpensive, effective method for conducting studies on S. alterniflora and other tidally influenced plants in controlled settings to be used not only to complement field studies, but also in locations without coastal access. PMID:25383265

  6. Additive effects of neurofeedback on the treatment of ADHD: A randomized controlled study.

    PubMed

    Lee, Eun-Jeong; Jung, Chul-Ho

    2017-02-01

    Neurofeedback (NF) has been identified as a "possibly efficacious" treatment in current evidence-based reviews; therefore, more research is needed to determine its effects. The current study examined the potential additive effect of NF for children diagnosed with ADHD beginning a medication trial first. Thirty-six children (6-12 years) with a DSM-IV-TR diagnosis of ADHD were randomly assigned to an NF with medication (NF condition) or a medication only condition. Children in the NF group attended 20 twice-weekly sessions. Outcome measures included individual cognitive performance scores (ADS, K-WISC-III), ADHD rating scores completed by their parents (ARS, CRS) and brainwave indices of left and right hemispheres before and after NF treatment. Significant additive treatment effect in any of the symptom variables was found and a reduction of theta waves in both the right and left hemispheres was recorded in NF condition participants. However our randomized controlled study could not demonstrate superior effects of combined NF on intelligent functioning compared to the medication treatment only. This study suggested any possible evidence of positive and additive treatment effects of NF on brainwaves and ADHD symptomatology.

  7. TEM and HRTEM studies of ball milled 6061 aluminium alloy powder with Zr addition.

    PubMed

    Lityńska-Dobrzyńska, L; Dutkiewicz, J; Maziarz, W; Rogal, Ł

    2010-03-01

    The effect of mechanical alloying on the microstructure of atomized 6061 aluminium alloy powder and 6061 powder with a zirconium addition was studied in the work. The atomized 6061 aluminium alloy powder and 6061 powder with addition of 2 wt.% Zr were milled in a planetary ball mill and investigated using X-ray diffraction measurements, conventional and high-resolution electron microscopy (TEM/HRTEM) and high-angle annular dark field scanning transmission electron microscopy combined with energy dispersive X-ray microanalysis. An increase of stresses was observed in milled powders after the refinement of crystallites beyond 100 nm. In the powder with zirconium addition, some part of the Zr atoms diffused in aluminium forming a solid solution containing up to 0.5 wt.% Zr. The remaining was found to form Zr-rich particles containing up to 88 wt.% Zr and were identified as face centred cubic (fcc) phase with lattice constant a= 0.48 nm. That fcc phase partially transformed into the L1(2) ordered phase. Eighty-hour milling brought an increase of microhardness (measured with Vickers method) from about 50 HV (168 MPa) for the initial 6061 powder to about 170 HV (552 MPa). The addition of zirconium had no influence on the microhardness.

  8. Hallux valgus: comparative study between two surgical techniques of proximal addition osteotomy

    PubMed Central

    Lara, Luiz Carlos Ribeiro; de Araujo, Bruno Vierno; Franco, Nelson; Hita, Roberto Minoru

    2012-01-01

    OBJECTIVE: To clinically and radiographically compare the results of treatment of hallux valgus, by two addition osteotomy techniques: one using resected exostosis, and the other using a plate fixation for addition wedge. METHODS: We evaluated 24 feet of 19 patients, mean age 51.3 years, affected by hallux valgus, with a mean follow-up of 50.1 months. 13 feet underwent addition osteotomy with resected exostosis (AORE) and 11 patients (11 feet) underwent addition osteotomy with plate (AOP). The AOFAS score, intermetatarsal 1 and 2 angles, and hallux valgus angle were evaluated before and after surgery. RESULTS: In the AORE technique, the mean preoperative AOFAS was 46.6, with IMA 14o and HVA 32o, while in the postoperative AOFAS it was 81.3, with IMA 9o and HVA 25o, and 92.3% satisfactory results. In the AOP technique, the mean preoperative AOFAS was 42.1, with IMA 15o and HVA 29o while in the postoperative AOFAS it was 77.4, with IMA 11o and HVA 23o and 81.8% of satisfactory results. CONCLUSIONS: Both techniques proved to be effective in the treatment of hallux valgus, both clinically and radiografically, with no statistical difference between them. Level of evidence III, Retrospective comparative study. PMID:24453631

  9. Clinical Relevance of Nontuberculous Mycobacteria Isolated from Sputum in a Gold Mining Workforce in South Africa: An Observational, Clinical Study

    PubMed Central

    van Halsema, Clare L.; Chihota, Violet N.; Gey van Pittius, Nicolaas C.; Fielding, Katherine L.; Lewis, James J.; van Helden, Paul D.; Churchyard, Gavin J.; Grant, Alison D.

    2015-01-01

    Background. The clinical relevance of nontuberculous mycobacteria (NTM), detected by liquid more than solid culture in sputum specimens from a South African mining workforce, is uncertain. We aimed to describe the current spectrum and relevance of NTM in this population. Methods. An observational study including individuals with sputum NTM isolates, recruited at workforce tuberculosis screening and routine clinics. Symptom questionnaires were administered at the time of sputum collection and clinical records and chest radiographs reviewed retrospectively. Results. Of 232 individuals included (228 (98%) male, median age 44 years), M. gordonae (60 individuals), M. kansasii (50), and M. avium complex (MAC: 38) were the commonest species. Of 38 MAC isolates, only 2 (5.3%) were from smear-positive sputum specimens and 30/38 grew in liquid but not solid culture. MAC was especially prevalent among symptomatic, HIV-positive individuals. HIV prevalence was high: 57/74 (77%) among those tested. No differences were found in probability of death or medical separation by NTM species. Conclusions. M. gordonae, M. kansasii, and MAC were the commonest NTM among miners with suspected tuberculosis, with most MAC from smear-negative specimens in liquid culture only. HIV testing and identification of key pathogenic NTM in this setting are essential to ensure optimal treatment. PMID:26180817

  10. Studies of nuclear reactions relevant to stellar or Big-Bang Nucleosynthesis using ICF plasmas at OMEGA

    NASA Astrophysics Data System (ADS)

    Zylstra, Alex; Herrmann, Hans; Kim, Yongho; Hale, Gerry; Paris, Mark; McEvoy, Aaron; Gatu Johnson, Maria; Frenje, Johan; Li, Chikang; Seguin, Fredrick; Sio, Hong; Petrasso, Richard; McNabb, Dennis; Sayre, Dan; Pino, Jesse; Brune, Carl; Bacher, Andy; Forrest, Chad; Glebov, Vladimir; Stoeckl, Christian; Janezic, Roger; Sangster, Craig

    2015-10-01

    The 3He+3He, T+3He, and p + D reactions directly relevant to Stellar or Big-Bang Nucleosynthesis (BBN) have been studied at the OMEGA laser facility using high-temperature low-density `exploding pusher' implosions. The advantage of using these plasmas is that they better mimic astrophysical systems than cold-target accelerator experiments. Measured proton spectra from the 3He3He reaction are used to constrain nuclear R-matrix modeling. The resulting T+3He gamma-ray data rule out an anomalously-high 6Li production during the Big Bang as an explanation to the high observed values in metal poor first generation stars. The proton spectrum from the T+3He reaction is also being used to constrain the R-matrix model. Recent experiments have probed the p + D reaction for the first time in a plasma; this reaction is relevant to energy production in protostars, brown dwarfs and at higher CM energies to BBN. This work was partially supported by the US DOE, NLUF, LLE, and GA.

  11. Studies of nuclear reactions relevant to stellar or Big-Bang Nucleosynthesis using ICF plasmas at OMEGA

    NASA Astrophysics Data System (ADS)

    Zylstra, Alex; Herrmann, Hans; Kim, Yongho; Hale, Gerry; Paris, Mark; McEvoy, Aaron; Gatu Johnson, Maria; Frenje, Johan; Li, Chikang; Seguin, Fredrick; Sio, Hong; Petrasso, Richard; McNabb, Dennis; Sayre, Dan; Pino, Jesse; Brune, Carl; Bacher, Andy; Forrest, Chad; Glebov, Vladimir; Stoeckl, Christian; Janezic, Roger; Sangster, Craig

    2015-11-01

    The 3He+3He, T+3He, and p +D reactions directly relevant to Stellar or Big-Bang Nucleosynthesis (BBN) have been studied at the OMEGA laser facility using high-temperature low-density `exploding pusher' implosions. The advantage of using these plasmas is that they better mimic astrophysical systems than cold-target accelerator experiments. Measured proton spectra from the 3He3He reaction are used to constrain nuclear R-matrix modeling. The resulting T+3He gamma-ray data rule out an anomalously-high 6Li production during the Big Bang as an explanation to the high observed values in metal poor first generation stars. The proton spectrum from the T+3He reaction is also being used to constrain the R-matrix model. Recent experiments have probed the p +D reaction for the first time in a plasma; this reaction is relevant to energy production in protostars, brown dwarfs and at higher CM energies to BBN. This work was partially supported by the US DOE, NLUF, LLE, and GA.

  12. Effect of Exogenous Phytase Addition on Soil Phosphatase Activities: a Fluorescence Spectroscopy Study.

    PubMed

    Yang, Xiao-zhu; Chen, Zhen-hua; Zhang, Yu-lan; Chen, Li-jun

    2015-05-01

    The utilization of organic phosphorus (P) has directly or indirectly improved after exogenous phytase was added to soil. However, the mechanism by which exogenous phytase affected the soil phosphatases (phosphomonoesterase and phosphodiesterase) activities was not clear. The present work was aimed to study red soil, brown soil and cinnamon soil phosphomonoesterase (acid and alkaline) (AcP and AlP) and phosphodiesterase (PD) activities responding to the addition of exogenous phytase (1 g phytase/50 g air dry soil sample) based on the measurements performed via a fluorescence detection method combined with 96 microplates using a TECAN Infinite 200 Multi-Mode Microplate Reader. The results indicated that the acid phosphomonoesterase activity was significantly enhanced in red soil (p≤0. 01), while it was significantly reduced in cinnamon soil; alkaline phosphomonoesterase activity was significantly enhanced in cinnamon soil (p≤ 0. 01), while it was significantly reduced in red soil; phosphodiesterase activity was increased in three soils but it was significantly increased in brown soil (p≤0. 01) after the addition of exogenous phytase. The activities still remained strong after eight days in different soils, which indicated that exogenous phytase addition could be enhance soil phosphatases activities effectively. This effect was not only related to soil properties, such as pH and phosphorus forms, but might also be related to the excreted enzyme amount of the stimulating microorganism. Using fluorescence spectroscopy to study exogenous phytase addition influence on soil phosphatase activities was the first time at home and abroad. Compared with the conventional spectrophotometric method, the fluorescence microplate method is an accurate, fast and simple to use method to determine the relationships among the soil phosphatases activities.

  13. Theoretical study of the hydroxyl radical addition to uracil and photochemistry of the formed U6OH• adduct.

    PubMed

    Francés-Monerris, Antonio; Merchán, Manuela; Roca-Sanjuán, Daniel

    2014-03-20

    Hydroxyl radical ((•)OH) is produced in biological systems by external or endogenous agents. It can damage DNA/RNA by attacking pyrimidine nucleobases through the addition to the C5═C6 double bond. The adduct resulting from the attachment at the C5 position prevails in the experimental measurements, although the reasons for this preference remain unclear. The first aim of this work is therefore to shed light on the comprehension of this important process. Thus, the thermal (•)OH addition to the C5═C6 double bond of uracil has been studied theoretically by using DFT, MP2, and the multiconfigurational CASPT2//CASSCF methodologies. The in-vacuo results obtained with the latter protocol plus the analysis of solvent effects support the experimental observation. A significant lower barrier height is predicted for the C5 pathway with respect to that of the C6 route. In contrast to the C5 adduct, the C6 adduct is able to absorb visible light. Hence, the second aim of the work is to study the photochemistry of this species using the CASPT2//CASSCF methodology within the framework of the photochemical reaction path approach (PRPA). The nonradiative decay to the ground state of this compound has been characterized. A photoreactive character is predicted for the C6 adduct in the excited states according to the presence of excited-state minima along the main decay channel. Finally, a new mechanism of photodissociation has been explored, which implies the photoinduced regeneration of the canonical nucleobase by irradiating with visible light, being therefore relevant in RNA protection against damage by reactive oxygen species.

  14. A synchrotron study of microstructure gradient in laser additively formed epitaxial Ni-based superalloy

    DOE PAGES

    Xue, Jiawei; Zhang, Anfeng; Li, Yao; ...

    2015-10-08

    Laser additive forming is considered to be one of the promising techniques to repair single crystal Ni-based superalloy parts to extend their life and reduce the cost. Preservation of the single crystalline nature and prevention of thermal mechanical failure are two of the most essential issues for the application of this technique. Here we employ synchrotron X-ray microdiffraction to evaluate the quality in terms of crystal orientation and defect distribution of a Ni-based superalloy DZ125L directly formed by a laser additive process rooted from a single crystalline substrate of the same material. We show that a disorientation gradient caused bymore » a high density of geometrically necessary dislocations and resultant subgrains exists in the interfacial region between the epitaxial and stray grains. This creates a potential relationship of stray grain formation and defect accumulation. In conclusion, the observation offers new directions on the study of performance control and reliability of the laser additive manufactured superalloys.« less

  15. Couples Counseling in Alzheimer’s Disease: Additional Clinical Findings from a Novel Intervention Study

    PubMed Central

    AUCLAIR, URSULA; EPSTEIN, CYNTHIA; MITTELMAN, MARY

    2009-01-01

    This article describes the clinical findings of a study designed to assess the benefit of counseling for couples, one of whom is in the early stage of Alzheimer’s disease (AD). We previously reported our findings based on the first 12 couples that enrolled in the study. Based on the treatment of 30 additional couples, we have refined our treatment strategy to include concepts of Gestalt Therapy and Transactional Analysis and identified prevalent issues of concern to this cohort. The study design has remained as described in the earlier article (Epstein et al., 2006), and has proven to be appropriate to meet the goals of this intervention as indicated by our clinical experience and feedback from the participating couples. Case vignettes demonstrate how to conduct the sessions so that the experience of each member of the dyad is validated, while acknowledging the differential impact of the disease on them. PMID:19865591

  16. Multicentre study highlighting clinical relevance of new high-throughput methodologies in molecular epidemiology of Pneumocystis jirovecii pneumonia.

    PubMed

    Esteves, F; de Sousa, B; Calderón, E J; Huang, L; Badura, R; Maltez, F; Bassat, Q; de Armas, Y; Antunes, F; Matos, O

    2016-06-01

    Pneumocystis jirovecii causes severe interstitial pneumonia (PcP) in immunosuppressed patients. This multicentre study assessed the distribution frequencies of epidemiologically relevant genetic markers of P. jirovecii in different geographic populations from Portugal, the USA, Spain, Cuba and Mozambique, and the relationship between the molecular data and the geographical and clinical information, based on a multifactorial approach. The high-throughput typing strategy for P. jirovecii characterization consisted of DNA pooling using quantitative real-time PCR followed by multiplex-PCR/single base extension. The frequencies of relevant P. jirovecii single nucleotide polymorphisms (mt85, SOD110, SOD215, DHFR312, DHPS165 and DHPS171) encoded at four loci were estimated in ten DNA pooled samples representing a total of 182 individual samples. Putative multilocus genotypes of P. jirovecii were shown to be clustered due to geographic differences but were also dependent on clinical characteristics of the populations studied. The haplotype DHFR312T/SOD110C/SOD215T was associated with severe AIDS-related PcP and high P. jirovecii burdens. The frequencies of this genetic variant of P. jirovecii were significantly higher in patients with AIDS-related PcP from Portugal and the USA than in the colonized patients from Portugal, and Spain, and children infected with P. jirovecii from Cuba or Mozambique, highlighting the importance of this haplotype, apparently associated with the severity of the disease and specific clinical groups. Patients from the USA and Mozambique showed higher rates of DHPS mutants, which may suggest the circulation of P. jirovecii organisms potentially related with trimethoprim-sulfamethoxazole resistance in those geographical regions. This report assessed the worldwide distribution of P. jirovecii haplotypes and their epidemiological impact in distinct geographic and clinical populations.

  17. Rapporteur report: cellular, animal and epidemiological studies of the effects of static magnetic fields relevant to human health.

    PubMed

    Leszczynski, Dariusz

    2005-01-01

    Three talks were presented in the session on "Cellular, Animal and Epidemiological Studies of the Effects of Static Magnetic Fields Relevant to Human Health". The first talk presented the in vitro effects of static magnetic fields on cell cultures. The second talk presented the in vivo evidence obtained from animal studies. The final, third talk, presented the evidence obtained from epidemiological studies. The overall conclusion of the three presentations and the following general discussion was that the scientific evidence available to date is weak and contains large gaps in knowledge either due to the poor quality of published studies or because of the lack of published research on certain health-related topics. It was emphasized that the rapid development of new technological applications of static magnetic fields (e.g. magnetic levitation trains or magnetic resonance imaging-MRI) results in the human population at large, in certain occupations, and in a selected population of clinical patients being exposed to ever increasing static magnetic field strengths. It is of concern that the knowledge presently available concerning the health effects of these strong static magnetic fields is lagging a long way behind technological development. In conclusion, it was suggested that there is an urgent need to perform new studies in all research areas (in vitro, in vivo and epidemiology) in order to fill the present gaps in knowledge and provide assurance that this technology will not cause any unwanted and unexpected health side effects.

  18. A water soluble additive to suppress respirable dust from concrete-cutting chainsaws: a case study.

    PubMed

    Summers, Michael P; Parmigiani, John P

    2015-01-01

    Respirable dust is of particular concern in the construction industry because it contains crystalline silica. Respirable forms of silica are a severe health threat because they heighten the risk of numerous respirable diseases. Concrete cutting, a common work practice in the construction industry, is a major contributor to dust generation. No studies have been found that focus on the dust suppression of concrete-cutting chainsaws, presumably because, during normal operation water is supplied continuously and copiously to the dust generation points. However, there is a desire to better understand dust creation at low water flow rates. In this case study, a water-soluble surfactant additive was used in the chainsaw's water supply. Cutting was performed on a free-standing concrete wall in a covered outdoor lab with a hand-held, gas-powered, concrete-cutting chainsaw. Air was sampled at the operator's lapel, and around the concrete wall to simulate nearby personnel. Two additive concentrations were tested (2.0% and 0.2%), across a range of fluid flow rates (0.38-3.8 Lpm [0.1-1.0 gpm] at 0.38 Lpm [0.1 gpm] increments). Results indicate that when a lower concentration of additive is used exposure levels increase. However, all exposure levels, once adjusted for 3 hours of continuous cutting in an 8-hour work shift, are below the Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) of 5 mg/m(3). Estimates were made using trend lines to predict the fluid flow rates that would cause respirable dust exposure to exceed both the OSHA PEL and the American Conference of Governmental Industrial Hygienists (ACGIH®) threshold limit value (TLV).

  19. Establishing a Clinically Relevant Large Animal Model Platform for TBI Therapy Development: Using Cyclosporin A as a Case Study

    PubMed Central

    Margulies, Susan S.; Kilbaugh, Todd; Sullivan, Sarah; Smith, Colin; Propert, Kathleen; Byro, Melissa; Saliga, Kristen; Costine, Beth A.; Duhaime, Ann-Christine

    2015-01-01

    We have developed the first immature large animal translational treatment trial of a pharmacologic intervention for traumatic brain injury (TBI) in children. The preclinical trial design includes multiple doses of the intervention in two different injury types (focal and diffuse) to bracket the range seen in clinical injury and uses two post-TBI delays to drug administration. Cyclosporin A (CsA) was used as a case study in our first implementation of the platform because of its success in multiple preclinical adult rodent TBI models and its current use in children for other indications. Tier 1 of the therapy development platform assessed the short-term treatment efficacy after 24 h of agent administration. Positive responses to treatment were compared with injured controls using an objective effect threshold established prior to the study. Effective CsA doses were identified to study in Tier 2. In the Tier 2 paradigm, agent is administered in a porcine intensive care unit utilizing neurological monitoring and clinically relevant management strategies, and intervention efficacy is defined as improvement in longer term behavioral endpoints above untreated injured animals. In summary, this innovative large animal preclinical study design can be applied to future evaluations of other agents that promote recovery or repair after TBI. PMID:25904045

  20. Functionalization of manganite nanoparticles and their interaction with biologically relevant small ligands: picosecond time-resolved FRET studies.

    PubMed

    Giri, Anupam; Makhal, Abhinandan; Ghosh, Barnali; Raychaudhuri, A K; Pal, Samir Kumar

    2010-12-01

    We report molecular functionalization of the promising manganite nanoparticles La0.67Sr0.33MnO3 (LSMO) for their solubilization in aqueous environments. The functionalization of individual NPs with the biocompatible citrate ligand, as confirmed by Fourier transform infrared (FTIR) spectroscopy, reveals that citrates are covalently attached to the surface of the NPs. UV-VIS spectroscopic studies on the citrate functionalized NPs reveals an optical band in the visible region. Uniform size selectivity (2.6 nm) of the functionalization process is confirmed from high resolution transmission electron microscope (HRTEM). In the present study we have used the optical band of the functionalized NPs to monitor their interaction with other biologically important ligands. Förster resonance energy transfer (FRET) of a covalently attached probe 4-nitrophenylanthranilate (NPA) with the capped NPs confirm the attachment of the NPA ligands to the surface functional group (-OH) of the citrate ligand. The FRET of a DNA base mimic, 2-aminopurine (2AP), with the NPs confirms the surface adsorption of 2AP. Our study may find relevance in the study of the interaction of individual manganite NPs with drug/ligand molecules.

  1. Establishing a Clinically Relevant Large Animal Model Platform for TBI Therapy Development: Using Cyclosporin A as a Case Study.

    PubMed

    Margulies, Susan S; Kilbaugh, Todd; Sullivan, Sarah; Smith, Colin; Propert, Kathleen; Byro, Melissa; Saliga, Kristen; Costine, Beth A; Duhaime, Ann-Christine

    2015-05-01

    We have developed the first immature large animal translational treatment trial of a pharmacologic intervention for traumatic brain injury (TBI) in children. The preclinical trial design includes multiple doses of the intervention in two different injury types (focal and diffuse) to bracket the range seen in clinical injury and uses two post-TBI delays to drug administration. Cyclosporin A (CsA) was used as a case study in our first implementation of the platform because of its success in multiple preclinical adult rodent TBI models and its current use in children for other indications. Tier 1 of the therapy development platform assessed the short-term treatment efficacy after 24 h of agent administration. Positive responses to treatment were compared with injured controls using an objective effect threshold established prior to the study. Effective CsA doses were identified to study in Tier 2. In the Tier 2 paradigm, agent is administered in a porcine intensive care unit utilizing neurological monitoring and clinically relevant management strategies, and intervention efficacy is defined as improvement in longer term behavioral endpoints above untreated injured animals. In summary, this innovative large animal preclinical study design can be applied to future evaluations of other agents that promote recovery or repair after TBI.

  2. Development of an inertial confinement fusion platform to study charged-particle-producing nuclear reactions relevant to nuclear astrophysics

    DOE PAGES

    Gatu Johnson, M.; Zylstra, A. B.; Bacher, A.; ...

    2017-03-28

    Here, this paper describes the development of a platform to study astrophysically relevant nuclear reactions using inertial-confinement fusion implosions on the OMEGA and National Ignition Facility laser facilities, with a particular focus on optimizing the implosions to study charged-particle- producing reactions. Primary requirements on the platform are high yield, for high statistics in the fusion product measurements, combined with low areal density, to allow the charged fusion products to escape. This is optimally achieved with direct-drive exploding pusher implosions using thin-glass-shell capsules. Mitigation strategies to eliminate a possible target sheath potential which would accelerate the emitted ions are discussed. Themore » potential impact of kinetic effects on the implosions is also considered. The platform is initially employed to study the complementary T(t,2n)α, T(3He,np)α and 3He(3He,2p)α reactions. Proof-of-principle results from the first experiments demonstrating the ability to accurately measure the energy and yields of charged particles are presented. Lessons learned from these experiments will be used in studies of other reactions. Ultimately, the goals are to explore thermonuclear reaction rates and fundamental nuclear physics in stellarlike plasma environments, and to push this new frontier of nuclear astrophysics into unique regimes not reachable through existing platforms, with thermal ion velocity distributions, plasma screening, and low reactant energies.« less

  3. Prazosin addition to fluvoxamine: A preclinical study and open clinical trial in OCD.

    PubMed

    Feenstra, Matthijs G P; Klompmakers, André; Figee, Martijn; Fluitman, Sjoerd; Vulink, Nienke; Westenberg, Herman G M; Denys, Damiaan

    2016-02-01

    The efficacy of selective serotonin reuptake inhibitors (SRIs) in psychiatric disorders may be "augmented" through the addition of atypical antipsychotic drugs. A synergistic increase in dopamine (DA) release in the prefrontal cortex has been suggested to underlie this augmentation effect, though the mechanism of action is not clear yet. We used in vivo microdialysis in rats to study DA release following the administration of combinations of fluvoxamine (10 mg/kg) and quetiapine (10 mg/kg) with various monoamine-related drugs. The results confirmed that the selective 5-HT1A antagonist WAY-100635 (0.05 mg/kg) partially blocked the fluvoxamine-quetiapine synergistic effect (maximum DA increase dropped from 325% to 214%). A novel finding is that the α1-adrenergic blocker prazosin (1 mg/kg), combined with fluvoxamine, partially mimicked the effect of augmentation (maximum DA increase 205%; area-under-the-curve 163%). As this suggested that prazosin augmentation might be tested in a clinical study, we performed an open clinical trial of prazosin 20 mg addition to SRI in therapy-resistant patients with obsessive-compulsive disorder applying for neurosurgery. A small, non-significant reduction in Yale Brown Obsessive Compulsive Scale (Y-BOCS) scores was observed in 10 patients and one patient was classified as a responder with a reduction in Y-BOCS scores of more than 25%. We suggest that future clinical studies augmenting SRIs with an α1-adrenergic blocker in less treatment resistant cases should be considered. The clinical trial "Prazosin in combination with a serotonin reuptake inhibitor for patients with Obsessive Compulsive disorder: an open label study" was registered at 24/05/2011 under trial number ISRCTN61562706: http://www.controlled-trials.com/ISRCTN61562706.

  4. In-vivo longitudinal MRI study: an assessment of melanoma brain metastases in a clinically relevant mouse model.

    PubMed

    Henry, Mariama N; Chen, Yuhua; McFadden, Catherine D; Simedrea, Felicia C; Foster, Paula J

    2015-04-01

    Brain metastases are an important clinical problem. Few animal models exist for melanoma brain metastases; many of which are not clinically relevant. Longitudinal MRI was implemented to examine the development of tumors in a clinically relevant mouse model of melanoma brain metastases. Fifty thousand human metastatic melanoma (A2058) cells were injected intracardially into nude mice. Three Tesla MRI was performed using a custom-built gradient insert coil and a mouse solenoid head coil. Imaging was performed on consecutive days at four time points. Tumor burden and volumes of metastases were measured from balanced steady-state free precession image data. Metastases with a disrupted blood-tumor barrier were identified from T1-weighted spin echo images acquired after administration of gadopentetic acid (Gd-DTPA). Metastases permeable to Gd-DTPA showed signal enhancement. The number of enhancing metastases was determined by comparing balanced steady-state free precession images with T1-weighted spin echo images. After the final imaging session, ex-vivo permeability and histological analyses were carried out. Imaging showed that both enhancing and nonenhancing brain metastases coexist in the brain, and that most metastases switched from the nonenhancing to the enhancing phenotype. Small numbers of brain metastases were enhancing when first detected by MRI and remained enhancing, whereas other metastases remained nonenhancing to Gd-DTPA throughout the experiment. No clear relationship existed between the permeability of brain metastases and size, brain location and age. Longitudinal in-vivo MRI is key to studying the complex and dynamic processes of metastasis and changes in the blood-tumor barrier permeability, which may lead to a better understanding of the variable responses of brain metastases to treatments.

  5. Culturally Relevant Teaching: Hip-Hop Pedagogy in Urban Schools. Counterpoints: Studies in the Postmodern Theory of Education. Volume 396

    ERIC Educational Resources Information Center

    Prier, Darius D.

    2012-01-01

    "Culturally Relevant Teaching" centers hip-hop culture as a culturally relevant form of critical pedagogy in urban pre-service teacher education programs. In this important book, Darius D. Prier explores how hip-hop artists construct a sense of democratic education and pedagogy with transformative possibilities in their schools and communities. In…

  6. Local versus Global Information Relevance in Website Use: A Case Study with the Information Literacy Portal AlfinEEES

    ERIC Educational Resources Information Center

    Marco, Francisco Javier Garcia; Pinto, Maria

    2010-01-01

    Introduction: A model to explore the relations among local and global relevance-based information behaviour is proposed that is based on objective and subjective measures of the relevance of the Website contents. Method: Global interest for the Website was researched using data on visits, while local use was explored with two surveys on the…

  7. A combined toxicity study of zinc oxide nanoparticles and vitamin C in food additives

    NASA Astrophysics Data System (ADS)

    Wang, Yanli; Yuan, Lulu; Yao, Chenjie; Ding, Lin; Li, Chenchen; Fang, Jie; Sui, Keke; Liu, Yuanfang; Wu, Minghong

    2014-11-01

    At present, safety evaluation standards for nanofood additives are made based on the toxic effects of a single additive. Since the size, surface properties and chemical nature influence the toxicity of nanomaterials, the toxicity may have dramatically changed when nanomaterials are used as food additives in a complex system. Herein, we investigated the combined toxicity of zinc oxide nanoparticles (ZnO NPs) and vitamin C (Vc, ascorbic acid). The results showed that Vc increased the cytotoxicity significantly compared with that of the ZnO only NPs. When the cells were exposed to ZnO NPs at a concentration less than 15 mg L-1, or to Vc at a concentration less than 300 mg L-1, there was no significant cytotoxicity, both in the case of gastric epithelial cell line (GES-1) and neural stem cells (NSCs). However, when 15 mg L-1 of ZnO NPs and 300 mg L-1 of Vc were introduced to cells together, the cell viability decreased sharply indicating significant cytotoxicity. Moreover, the significant increase in toxicity was also shown in the in vivo experiments. The dose of the ZnO NPs and Vc used in the in vivo study was calculated according to the state of food and nutrition enhancer standard. After repeated oral exposure to ZnO NPs plus Vc, the injury of the liver and kidneys in mice has been indicated by the change of these indices. These findings demonstrate that the synergistic toxicity presented in a complex system is essential for the toxicological evaluation and safety assessment of nanofood.At present, safety evaluation standards for nanofood additives are made based on the toxic effects of a single additive. Since the size, surface properties and chemical nature influence the toxicity of nanomaterials, the toxicity may have dramatically changed when nanomaterials are used as food additives in a complex system. Herein, we investigated the combined toxicity of zinc oxide nanoparticles (ZnO NPs) and vitamin C (Vc, ascorbic acid). The results showed that Vc increased the

  8. Rate Constants of Hydroperoxyl Radical Addition to Cyclic Nitrones: A DFT Study

    PubMed Central

    Villamena, Frederick A.; Merle, John K.; Hadad, Christopher M.; Zweier*, Jay L.

    2008-01-01

    Nitrones are potential synthetic antioxidants against the reduction of radical-mediated oxidative damage in cells, and as analytical reagent for the identification of HO2• and other such transient species. In this work, the PCM/B3LYP/6−31+G(d,p)//B3LYP/6−31G(d) and PCM/mPW1K/6−31+G(d,p) density functional theory (DFT) methods were employed to predict the reactivity of HO2• with various functionalized nitrones as spin traps. The calculated second-order rate constants and free energies of reaction at both levels of theory were in the range of 100−103 M−1 s−1 and 1 to −12 kcal mol−1, respectively, and the rate constants for some nitrones are on the same order of magnitude as those observed experimentally. The trend in HO2• reactivity to nitrones could not be explained solely on the basis of the relationship of the theoretical positive charge densities on the nitronyl-C, with their respective ionization potentials, electron affinities, rate constants, or free energies of reaction. However, various modes of intramolecular H-bonding interaction were observed at the transition state (TS) structures of HO2• addition to nitrones. The presence of intramolecular H-bonding interactions in the transition states were predicted and may play a significant role towards a facile addition of HO2• to nitrones. In general, HO2• addition to ethoxycarbonyl- and spirolactam- substituted nitrones, as well as those nitrones without electron-withdrawing substituents, such as 5,5-dimethyl-pyrroline N-oxide (DMPO) and 5-spirocyclopentyl-pyrroline N-oxide (CPPO), are most preferred compared to the methylcarbamoyl-substituted nitrones. This study suggests that the use of specific spin traps for efficient trapping of HO2• could pave the way toward improved radical detection and antioxidant protection. PMID:17845014

  9. A combined toxicity study of zinc oxide nanoparticles and vitamin C in food additives.

    PubMed

    Wang, Yanli; Yuan, Lulu; Yao, Chenjie; Ding, Lin; Li, Chenchen; Fang, Jie; Sui, Keke; Liu, Yuanfang; Wu, Minghong

    2014-12-21

    At present, safety evaluation standards for nanofood additives are made based on the toxic effects of a single additive. Since the size, surface properties and chemical nature influence the toxicity of nanomaterials, the toxicity may have dramatically changed when nanomaterials are used as food additives in a complex system. Herein, we investigated the combined toxicity of zinc oxide nanoparticles (ZnO NPs) and vitamin C (Vc, ascorbic acid). The results showed that Vc increased the cytotoxicity significantly compared with that of the ZnO only NPs. When the cells were exposed to ZnO NPs at a concentration less than 15 mg L(-1), or to Vc at a concentration less than 300 mg L(-1), there was no significant cytotoxicity, both in the case of gastric epithelial cell line (GES-1) and neural stem cells (NSCs). However, when 15 mg L(-1) of ZnO NPs and 300 mg L(-1) of Vc were introduced to cells together, the cell viability decreased sharply indicating significant cytotoxicity. Moreover, the significant increase in toxicity was also shown in the in vivo experiments. The dose of the ZnO NPs and Vc used in the in vivo study was calculated according to the state of food and nutrition enhancer standard. After repeated oral exposure to ZnO NPs plus Vc, the injury of the liver and kidneys in mice has been indicated by the change of these indices. These findings demonstrate that the synergistic toxicity presented in a complex system is essential for the toxicological evaluation and safety assessment of nanofood.

  10. A study of pyrazines in cigarettes and how additives might be used to enhance tobacco addiction

    PubMed Central

    Alpert, Hillel R; Agaku, Israel T; Connolly, Gregory N

    2016-01-01

    Background Nicotine is known as the drug that is responsible for the addicted behaviour of tobacco users, but it has poor reinforcing effects when administered alone. Tobacco product design features enhance abuse liability by (A) optimising the dynamic delivery of nicotine to central nervous system receptors, and affecting smokers’ withdrawal symptoms, mood and behaviour; and (B) effecting conditioned learning, through sensory cues, including aroma, touch and visual stimulation, to create perceptions of pending nicotine reward. This study examines the use of additives called ‘pyrazines’, which may enhance abuse potential, their introduction in ‘lights’ and subsequently in the highly market successful Marlboro Lights (Gold) cigarettes and eventually many major brands. Methods We conducted internal tobacco industry research using online databases in conjunction with published scientific literature research, based on an iterative feedback process. Results Tobacco manufacturers developed the use of a range of compounds, including pyrazines, in order to enhance ‘light’ cigarette products’ acceptance and sales. Pyrazines with chemosensory and pharmacological effects were incorporated in the first ‘full-flavour, low-tar’ product achieving high market success. Such additives may enhance dependence by helping to optimise nicotine delivery and dosing and through cueing and learned behaviour. Conclusions Cigarette additives and ingredients with chemosensory effects that promote addiction by acting synergistically with nicotine, increasing product appeal, easing smoking initiation, discouraging cessation or promoting relapse should be regulated by the US Food and Drug Administration. Current models of tobacco abuse liability could be revised to include more explicit roles with regard to non-nicotine constituents that enhance abuse potential. PMID:26063608

  11. Impact of contacting study authors to obtain additional data for systematic reviews: diagnostic accuracy studies for hepatic fibrosis

    PubMed Central

    2014-01-01

    Background Seventeen of 172 included studies in a recent systematic review of blood tests for hepatic fibrosis or cirrhosis reported diagnostic accuracy results discordant from 2 × 2 tables, and 60 studies reported inadequate data to construct 2 × 2 tables. This study explores the yield of contacting authors of diagnostic accuracy studies and impact on the systematic review findings. Methods Sixty-six corresponding authors were sent letters requesting additional information or clarification of data from 77 studies. Data received from the authors were synthesized with data included in the previous review, and diagnostic accuracy sensitivities, specificities, and positive and likelihood ratios were recalculated. Results Of the 66 authors, 68% were successfully contacted and 42% provided additional data for 29 out of 77 studies (38%). All authors who provided data at all did so by the third emailed request (ten authors provided data after one request). Authors of more recent studies were more likely to be located and provide data compared to authors of older studies. The effects of requests for additional data on the conclusions regarding the utility of blood tests to identify patients with clinically significant fibrosis or cirrhosis were generally small for ten out of 12 tests. Additional data resulted in reclassification (using median likelihood ratio estimates) from less useful to moderately useful or vice versa for the remaining two blood tests and enabled the calculation of an estimate for a third blood test for which previously the data had been insufficient to do so. We did not identify a clear pattern for the directional impact of additional data on estimates of diagnostic accuracy. Conclusions We successfully contacted and received results from 42% of authors who provided data for 38% of included studies. Contacting authors of studies evaluating the diagnostic accuracy of serum biomarkers for hepatic fibrosis and cirrhosis in hepatitis C patients

  12. A Mechanistic Study of Halogen Addition and Photoelimination from π-Conjugated Tellurophenes.

    PubMed

    Carrera, Elisa I; Lanterna, Anabel E; Lough, Alan J; Scaiano, Juan C; Seferos, Dwight S

    2016-03-02

    The ability to drive reactivity using visible light is of importance for many disciplines of chemistry and has significant implications for sustainable chemistry. Identifying photochemically active compounds and understanding photochemical mechanisms is important for the development of useful materials for synthesis and catalysis. Here we report a series of photoactive diphenyltellurophene compounds bearing electron-withdrawing and electron-donating substituents synthesized by alkyne coupling/ring closing or palladium-catalyzed ipso-arylation chemistry. The redox chemistry of these compounds was studied with respect to oxidative addition and photoelimination of bromine, which is of importance for energy storage reactions involving X2. The oxidative addition reaction mechanism was studied using density functional theory, the results of which support a three-step mechanism involving the formation of an initial η(1) association complex, a monobrominated intermediate, and finally the dibrominated product. All of the tellurophene derivatives undergo photoreduction using 430, 447, or 617 nm light depending on the absorption properties of the compound. Compounds bearing electron-withdrawing substituents have the highest photochemical quantum efficiencies in the presence of an alkene trap, with efficiencies of up to 42.4% for a pentafluorophenyl-functionalized tellurophene. The photoelimination reaction was studied in detail through bromine trapping experiments and laser flash photolysis, and a mechanism is proposed. The photoreaction, which occurs by release of bromine radicals, is competitive with intersystem crossing to the triplet state of the brominated species, as evidenced by the formation of singlet oxygen. These findings should be useful for the design of new photochemically active compounds supported by main-group elements.

  13. Hydrogen atom addition to the surface of graphene nanoflakes: A density functional theory study

    NASA Astrophysics Data System (ADS)

    Tachikawa, Hiroto

    2017-02-01

    Polycyclic aromatic hydrocarbons (PAHs) provide a 2-dimensional (2D) reaction surface in 3-dimensional (3D) interstellar space and have been utilized as a model of graphene surfaces. In the present study, the reaction of PAHs with atomic hydrogen was investigated by means of density functional theory (DFT) to systematically elucidate the binding nature of atomic hydrogen to graphene nanoflakes. PAHs with n = 4-37 were chosen, where n indicates the number of benzene rings. Activation energies of hydrogen addition to the graphene surface were calculated to be 5.2-7.0 kcal/mol at the CAM-B3LYP/6-311G(d,p) level, which is almost constant for all PAHs. The binding energies of hydrogen atom were slightly dependent on the size (n): 14.8-28.5 kcal/mol. The absorption spectra showed that a long tail is generated at the low-energy region after hydrogen addition to the graphene surface. The electronic states of hydrogenated graphenes were discussed on the basis of theoretical results.

  14. Resources allocation in healthcare for cancer: a case study using generalised additive mixed models.

    PubMed

    Musio, Monica; Sauleau, Erik A; Augustin, Nicole H

    2012-11-01

    Our aim is to develop a method for helping resources re-allocation in healthcare linked to cancer, in order to replan the allocation of providers. Ageing of the population has a considerable impact on the use of health resources because aged people require more specialised medical care due notably to cancer. We propose a method useful to monitor changes of cancer incidence in space and time taking into account two age categories, according to healthcar general organisation. We use generalised additive mixed models with a Poisson response, according to the methodology presented in Wood, Generalised additive models: an introduction with R. Chapman and Hall/CRC, 2006. Besides one-dimensional smooth functions accounting for non-linear effects of covariates, the space-time interaction can be modelled using scale invariant smoothers. Incidence data collected by a general cancer registry between 1992 and 2007 in a specific area of France is studied. Our best model exhibits a strong increase of the incidence of cancer along time and an obvious spatial pattern for people more than 70 years with a higher incidence in the central band of the region. This is a strong argument for re-allocating resources for old people cancer care in this sub-region.

  15. Covalent binding of aniline to humic substances. 2. 15N NMR studies of nucleophilic addition reactions

    USGS Publications Warehouse

    Thorn, K.A.; Pettigrew, P.J.; Goldenberg, W.S.; Weber, E.J.

    1996-01-01

    Aromatic amines are known to undergo covalent binding with humic substances in the environment. Although previous studies have examined reaction conditions and proposed mechanisms, there has been no direct spectroscopic evidence for the covalent binding of the amines to the functional groups in humic substances. In order to further elucidate the reaction mechanisms, the Suwannee River and IHSS soil fulvic and humic acids were reacted with 15N-labeled aniline at pH 6 and analyzed using 15N NMR spectrometry. Aniline underwent nucleophilic addition reactions with the quinone and other carbonyl groups in the samples and became incorporated in the form of anilinohydroquinone, anilinoquinone, anilide, imine, and heterocyclic nitrogen, the latter comprising 50% or more of the bound amine. The anilide and anilinohydroquinone nitrogens were determined to be susceptible to chemical exchange by ammonia. In the case of Suwannee River fulvic acid, reaction under anoxic conditions and pretreatment with sodium borohydride or hydroxylamine prior to reaction under oxic conditions resulted in a decrease in the proportion of anilinohydroquinone nitrogen incorporated. The relative decrease in the incorporation of anilinohydroquinone nitrogen with respect to anilinoquinone nitrogen under anoxic conditions suggested that inter- or intramolecular redox reactions accompanied the nucleophilic addition reactions.

  16. Toxicogenomics concepts and applications to study hepatic effects of food additives and chemicals

    SciTech Connect

    Stierum, Rob . E-mail: stierum@voeding.tno.nl; Heijne, Wilbert; Kienhuis, Anne; Ommen, Ben van; Groten, John

    2005-09-01

    Transcriptomics, proteomics and metabolomics are genomics technologies with great potential in toxicological sciences. Toxicogenomics involves the integration of conventional toxicological examinations with gene, protein or metabolite expression profiles. An overview together with selected examples of the possibilities of genomics in toxicology is given. The expectations raised by toxicogenomics are earlier and more sensitive detection of toxicity. Furthermore, toxicogenomics will provide a better understanding of the mechanism of toxicity and may facilitate the prediction of toxicity of unknown compounds. Mechanism-based markers of toxicity can be discovered and improved interspecies and in vitro-in vivo extrapolations will drive model developments in toxicology. Toxicological assessment of chemical mixtures will benefit from the new molecular biological tools. In our laboratory, toxicogenomics is predominantly applied for elucidation of mechanisms of action and discovery of novel pathway-supported mechanism-based markers of liver toxicity. In addition, we aim to integrate transcriptome, proteome and metabolome data, supported by bioinformatics to develop a systems biology approach for toxicology. Transcriptomics and proteomics studies on bromobenzene-mediated hepatotoxicity in the rat are discussed. Finally, an example is shown in which gene expression profiling together with conventional biochemistry led to the discovery of novel markers for the hepatic effects of the food additives butylated hydroxytoluene, curcumin, propyl gallate and thiabendazole.

  17. Study on Friction and Wear Properties of Silver Matrix Brush Material with Different Additives

    NASA Astrophysics Data System (ADS)

    Chen, Xiaoli; Wang, Wenfang; Hong, Yu; Wu, Yucheng

    2013-07-01

    Friction and wear processes of AgCuX (G, CF and AlN) composites-CuAgV alloy friction pair and effects of different additive content in silver based composite on friction and wear behavior are studied in this paper. The microstructure of the brush wear surface is observed by SEM. The results show that when graphite content is up to 9 wt.%, Ag-Cu-CF-G composite exhibits the best wear properties; when the content of aluminum nitride is up to 0.5 wt.%, Ag-Cu-AlN-G composites has the most comprehensive performance. The wear loss of both composites arises with the increase of both pressure and speed, but when speed reaches a critical value, the increased amplitude of wear loss tends to be steady.

  18. Ribotyping as an additional molecular marker for studying Neisseria meningitidis serogroup B epidemic strains.

    PubMed Central

    Tondella, M L; Sacchi, C T; Neves, B C

    1994-01-01

    The molecular method of ribotyping was used as an additional epidemiological marker to study the epidemic strains of Neisseria meningitidis serogroup B, referred to as the ET-5 complex, responsible for the epidemic which occurred in greater São Paulo, Brazil. Ribotyping analysis of these strains showed only a single rRNA gene restriction pattern (Rb1), obtained with ClaI restriction enzyme. This method, as well as multilocus enzyme electrophoresis, provided useful information about the clonal characteristics of the N. meningitidis serogroup B strains isolated during this epidemic. The N. meningitidis serogroup B isolates obtained from epidemics which occurred in Norway, Chile, and Cuba also demonstrated the same pattern (Rb1). Ribotyping was a procedure which could be applied to a large number of isolates and was felt to be appropriate for routine use in laboratories, especially because of the convenience of using nonradioactive probes. Images PMID:7852566

  19. Spectroscopic studies of nucleic acid additions during seed-mediated growth of gold nanoparticles

    PubMed Central

    Tapp, Maeling; Sullivan, Rick; Dennis, Patrick; Naik, Rajesh R.

    2015-01-01

    The effect of adding nucleic acids to gold seeds during the growth stage of either nanospheres or nanorods was investigated using UV-Vis spectroscopy to reveal any oligonucleotide base or structure-specific effects on nanoparticle growth kinetics or plasmonic signatures. Spectral data indicate that the presence of DNA duplexes during seed ageing drastically accelerated nanosphere growth while the addition of single-stranded polyadenine at any point during seed ageing induces nanosphere aggregation. For seeds added to a gold nanorod growth solution, single-stranded polythymine induces a modest blue-shift in the longitudinal peak wavelength. Moreover, a particular sequence comprised of 50% thymine bases was found to induce a faster, more dramatic blue-shift in the longitudinal peak wavelength compared to any of the homopolymer incubation cases. Monomeric forms of the nucleic acids, however, do not yield discernable spectral differences in any of the gold suspensions studied. PMID:25960601

  20. Modular system for studying tonal sound excitation in resonators with heat addition and mean flow.

    PubMed

    Matveev, Konstantin I; Hernandez, Rafael

    2012-03-01

    An educational experimental system has been developed for studying tonal sound generation in acoustic resonators. Tones are excited by either heat addition or vortex shedding in the presence of mean flow. The system construction is straightforward and inexpensive. Several test arrangements and experimental data are described in this paper. The experimental setups include a modified Rijke tube, a standing-wave thermoacoustic engine, a baffled tube with mean flow, and an acoustic energy harvester with a piezoelement. Simplified mathematical models for interpreting data are discussed, and references are provided to literature with more advanced analyses. The developed system can assist both graduate and undergraduate students in understanding acoustic instabilities via conducting and analyzing interesting experiments.

  1. Genetic Assessment of Additional Endophenotypes from the Consortium on the Genetics of Schizophrenia Family Study

    PubMed Central

    Greenwood, Tiffany A.; Lazzeroni, Laura C.; Calkins, Monica E.; Freedman, Robert; Green, Michael F.; Gur, Raquel E.; Gur, Ruben C.; Light, Gregory A.; Nuechterlein, Keith H.; Olincy, Ann; Radant, Allen D.; Seidman, Larry J.; Siever, Larry J.; Silverman, Jeremy M.; Stone, William S.; Sugar, Catherine A.; Swerdlow, Neal R.; Tsuang, Debby W.; Tsuang, Ming T.; Turetsky, Bruce I.; Braff, David L.

    2015-01-01

    The Consortium on the Genetics of Schizophrenia Family Study (COGS-1) has previously reported our efforts to characterize the genetic architecture of 12 primary endophenotypes for schizophrenia. We now report the characterization of 13 additional measures derived from the same endophenotype test paradigms in the COGS-1 families. Nine of the measures were found to discriminate between schizophrenia patients and controls, were significantly heritable (31 to 62%), and were sufficiently independent of previously assessed endophenotypes, demonstrating utility as additional endophenotypes. Genotyping via a custom array of 1536 SNPs from 94 candidate genes identified associations for CTNNA2, ERBB4, GRID1, GRID2, GRIK3, GRIK4, GRIN2B, NOS1AP, NRG1, and RELN across multiple endophenotypes. An experiment-wide p value of 0.003 suggested that the associations across all SNPs and endophenotypes collectively exceeded chance. Linkage analyses performed using a genome-wide SNP array further identified significant or suggestive linkage for six of the candidate endophenotypes, with several genes of interest located beneath the linkage peaks (e.g., CSMD1, DISC1, DLGAP2, GRIK2, GRIN3A, and SLC6A3). While the partial convergence of the association and linkage likely reflects differences in density of gene coverage provided by the distinct genotyping platforms, it is also likely an indication of the differential contribution of rare and common variants for some genes and methodological differences in detection ability. Still, many of the genes implicated by COGS through endophenotypes have been identified by independent studies of common, rare, and de novo variation in schizophrenia, all converging on a functional genetic network related to glutamatergic neurotransmission that warrants further investigation. PMID:26597662

  2. Mössbauer spectroscopy: an excellent additional tool for the study of magnetic soils and sediments

    NASA Astrophysics Data System (ADS)

    Vandenberghe, R. E.; Hus, J. J.; de Grave, E.

    2009-04-01

    Since the discovery a half century ago of the resonant gamma absorption, known as the Mössbauer effect, the derived spectroscopic method (MS) has proven to be a very suitable tool for the characterization of soil and rock minerals. From the conventional absorption spectra of iron containing compounds, so-called hyperfine parameters are derived which are more or less typical for each kind of mineral. So, MS has a certain analytical power for the characterization of iron-bearing minerals. This is especially true for magnetic minerals for which the spectrum contains an additional hyperfine parameter. Moreover, MS also allows retrieving information about the magnetic structure and behavior. Because the relative area of the spectra is to some extent proportional to the amount of iron atoms in their environment, MS yields not only quantitative information about the various minerals present but also about the iron in the different crystallographic sites. The power of MS as an excellent additional tool for the study of magnetic soils and sediments could be well demonstrated in the joint research with Jozef Hus (CPG-IRM, Dourbes). In our common work, the emphasis went mainly to the study of Chinese loess and soils. Using MS on magnetically separated samples the various magnetic species in a loess and its associated soil were for the first time discerned in a direct way. Further, magnetically enriched samples of four different loess/paleosol couplets from a loess sequence in Huangling have been systematically investigated by MS. From the obtained qualitative and quantitative information the neoformation of magnetite/maghemite in the soils, responsible for the increased observed remanence and susceptibility, could be evidenced.

  3. Spin-probe ESR and molecular modeling studies on calcium carbonate dispersions in overbased detergent additives.

    PubMed

    Montanari, Luciano; Frigerio, Francesco

    2010-08-15

    Oil-soluble calcium carbonate colloids are used as detergent additives in lubricating oils. They are colloidal dispersions of calcium carbonate particles stabilized by different surfactants; in this study alkyl-aryl-sulfonates and sulfurized alkyl-phenates, widely used in the synthesis of these additives, are considered. The physical properties of surfactant layers surrounding the surfaces of calcium carbonate particles were analyzed by using some nitroxide spin-probes (stable free radicals) and observing the corresponding ESR spectra. The spin-probe molecules contain polar groups which tend to tether them to the carbonate particle polar surface. They can reach these surfaces only if the surfactant layers are not very compact, hence the relative amounts of spin-probe molecules accessing carbonate surfaces are an index of the compactness of surfactant core. ESR signals of spin-probe molecules dissolved in oil or "locked" near the carbonate surfaces are different because of the different molecular mobility. Through deconvolution of the ESR spectra, the fraction of spin-probes penetrating surfactant shells have been calculated, and differences were observed according to the surfactant molecular structures. Moreover, by using specially labeled spin-probes based on stearic acids, functionalized at different separations from the carboxylic acid group, it was possible to interrogate the molecular physical behavior of surfactant shells at different distances from carbonate surfaces. Molecular modeling was applied to generate some three-dimensional micellar models of the colloidal stabilizations of the stabilized carbonate particles with different molecular structures of the surfactant. The diffusion of spin-probe molecules into the surfactant shells were studied by applying a starting force to push the molecules towards the carbonate surfaces and then observing the ensuing behavior. The simulations are in accordance with the ESR data and show that the geometrical

  4. Parametric Study of Urban-Like Topographic Statistical Moments Relevant to a Priori Modelling of Bulk Aerodynamic Parameters

    NASA Astrophysics Data System (ADS)

    Zhu, Xiaowei; Iungo, G. Valerio; Leonardi, Stefano; Anderson, William

    2017-02-01

    For a horizontally homogeneous, neutrally stratified atmospheric boundary layer (ABL), aerodynamic roughness length, z_0, is the effective elevation at which the streamwise component of mean velocity is zero. A priori prediction of z_0 based on topographic attributes remains an open line of inquiry in planetary boundary-layer research. Urban topographies - the topic of this study - exhibit spatial heterogeneities associated with variability of building height, width, and proximity with adjacent buildings; such variability renders a priori, prognostic z_0 models appealing. Here, large-eddy simulation (LES) has been used in an extensive parametric study to characterize the ABL response (and z_0) to a range of synthetic, urban-like topographies wherein statistical moments of the topography have been systematically varied. Using LES results, we determined the hierarchical influence of topographic moments relevant to setting z_0. We demonstrate that standard deviation and skewness are important, while kurtosis is negligible. This finding is reconciled with a model recently proposed by Flack and Schultz (J Fluids Eng 132:041203-1-041203-10, 2010), who demonstrate that z_0 can be modelled with standard deviation and skewness, and two empirical coefficients (one for each moment). We find that the empirical coefficient related to skewness is not constant, but exhibits a dependence on standard deviation over certain ranges. For idealized, quasi-uniform cubic topographies and for complex, fully random urban-like topographies, we demonstrate strong performance of the generalized Flack and Schultz model against contemporary roughness correlations.

  5. In vitro studies of eggplant (Solanum melongena) phenolics as inhibitors of key enzymes relevant for type 2 diabetes and hypertension.

    PubMed

    Kwon, Y-I; Apostolidis, E; Shetty, K

    2008-05-01

    National Diabetes Education Program of NIH, Mayo Clinic and American Diabetes Association recommend eggplant-based diet as a choice for management of type 2 diabetes. The rationale for this suggestion is the high fiber and low soluble carbohydrate content of eggplant. We propose that a more physiologically relevant explanation lies in the phenolic-linked antioxidant activity and alpha-glucosidase inhibitory potential of eggplant which could reduce hyperglycemia-induced pathogenesis. Results from this study indicate that phenolic-enriched extracts of eggplant with moderate free radical scavenging-linked antioxidant activity had high alpha-glucosidase inhibitory activity and in specific cases moderate to high angiotensin I-converting enzyme (ACE) inhibitory activity. Inhibition of these enzymes provide a strong biochemical basis for management of type 2 diabetes by controlling glucose absorption and reducing associated hypertension, respectively. This phenolic antioxidant-enriched dietary strategy also has the potential to reduce hyperglycemia-induced pathogenesis linked to cellular oxidation stress. These results provide strong rationale for further animal and clinical studies.

  6. Surface Enhanced Raman Spectroscopy on Carbonate Fluids at High Pressures: A New Technique to Study Fluid Species Under Geologically Relevant Conditions

    NASA Astrophysics Data System (ADS)

    Chopelas, A.; Black, J. R.; Kavner, A.; Manning, C. E.

    2010-12-01

    concentrations with standard Raman techniques but with at least an order of magnitude enhancement. Our experiments suggest that SERS in conjunction with the hydrothermal diamond anvil cell is a promising technique to study not only oxidized carbon but also a variety of species such as sulfates, nitrates, or silicates in aqueous solutions at Earth-relevant conditions. In addition, it has promise as a method to examine species adsorbed specifically on mineral surfaces, and to ascertain the influence of pressure and temperature on the chemical behavior of species at fluid/mineral interfaces.

  7. Passive seismic monitoring of natural and induced earthquakes: case studies, future directions and socio-economic relevance

    USGS Publications Warehouse

    Bohnhoff, Marco; Dresen, Georg; Ellsworth, William L.; Ito, Hisao; Cloetingh, Sierd; Negendank, Jörg

    2010-01-01

    An important discovery in crustal mechanics has been that the Earth’s crust is commonly stressed close to failure, even in tectonically quiet areas. As a result, small natural or man-made perturbations to the local stress field may trigger earthquakes. To understand these processes, Passive Seismic Monitoring (PSM) with seismometer arrays is a widely used technique that has been successfully applied to study seismicity at different magnitude levels ranging from acoustic emissions generated in the laboratory under controlled conditions, to seismicity induced by hydraulic stimulations in geological reservoirs, and up to great earthquakes occurring along plate boundaries. In all these environments the appropriate deployment of seismic sensors, i.e., directly on the rock sample, at the earth’s surface or in boreholes close to the seismic sources allows for the detection and location of brittle failure processes at sufficiently low magnitude-detection threshold and with adequate spatial resolution for further analysis. One principal aim is to develop an improved understanding of the physical processes occurring at the seismic source and their relationship to the host geologic environment. In this paper we review selected case studies and future directions of PSM efforts across a wide range of scales and environments. These include induced failure within small rock samples, hydrocarbon reservoirs, and natural seismicity at convergent and transform plate boundaries. Each example represents a milestone with regard to bridging the gap between laboratory-scale experiments under controlled boundary conditions and large-scale field studies. The common motivation for all studies is to refine the understanding of how earthquakes nucleate, how they proceed and how they interact in space and time. This is of special relevance at the larger end of the magnitude scale, i.e., for large devastating earthquakes due to their severe socio-economic impact.

  8. Impact of micropollutants on the life-history traits of the mosquito Aedes aegypti: On the relevance of transgenerational studies.

    PubMed

    Prud'homme, Sophie M; Chaumot, Arnaud; Cassar, Eva; David, Jean-Philippe; Reynaud, Stéphane

    2017-01-01

    Hazard assessment of chemical contaminants often relies on short term or partial life-cycle ecotoxicological tests, while the impact of low dose throughout the entire life cycle of species across multiple generations has been neglected. This study aimed at identifying the individual and population-level consequences of chronic water contamination by environmental concentrations of three organic micropollutants, ibuprofen, bisphenol A and benzo[a]pyrene, on Aedes aegypti mosquito populations in experimental conditions. Life-history assays spanning the full life-cycle of exposed individuals and their progeny associated with population dynamics modelling evidenced life-history traits alterations in unexposed progenies of individuals chronically exposed to 1 μg/L ibuprofen or 0.6 μg/L benzo[a]pyrene. The progeny of individuals exposed to ibuprofen showed an accelerated development while the progeny of individuals exposed to benzo[a]pyrene showed a developmental acceleration associated with an increase in mortality rate during development. These life-history changes due to pollutants exposure resulted in relatively shallow increase of Ae. aegypti asymptotic population growth rate. Multigenerational exposure for six generations revealed an evolution of population response to ibuprofen and benzo[a]pyrene across generations, leading to a loss of previously identified transgenerational effects and to the emergence of a tolerance to the bioinsecticide Bacillus turingiensis israelensis (Bti). This study shed light on the short and long term impact of environmentally relevant doses of ibuprofen and benzo[a]pyrene on Ae. aegypti life-history traits and insecticide tolerance, raising unprecedented perspectives about the influence of surface water pollution on vector-control strategies. Overall, our approach highlights the importance of considering the entire life cycle of organisms, and the necessity to assess the transgenerational effects of pollutants in ecotoxicological

  9. The impact of bismuth addition to sequential treatment on Helicobacter pylori eradication: A pilot study.

    PubMed

    Basyigit, Sebahat; Kefeli, Ayse; Sapmaz, Ferdane; Yeniova, Abdullah Ozgür; Asilturk, Zeliha; Hokkaomeroglu, Murat; Uzman, Metin; Nazligul, Yasar

    2015-10-25

    The success of the current anti-Helicobacter pylori (H. pylori) treatment protocols is reported to decrease by years, and research is needed to strengthen the H. pylori eradication treatment. Sequential treatment (ST), one of the treatment modalities for H. pylori eradication, includes amoxicillin 1 gr b.i.d and proton pump inhibitor b.i.d for first 5 days and then includes clarithromycin 500 mg b.i.d, metronidazole 500 mg b.i.d and a proton pump inhibitor b.i.d for remaining 5 days. In this study, we investigated efficacy and tolerability of bismuth addition in to ST. We included patients that underwent upper gastrointestinal endoscopy in which H. pylori infection was diagnosed by histological examination of antral and corporal gastric mucosa biopsy. Participants were randomly administered ST or bismuth containing ST (BST) protocols for the first-line H. pylori eradication therapy. Participants have been tested by urea breath test for eradication success 6 weeks after the completion of treatment. One hundred and fifty patients (93 female, 57 male) were enrolled. There were no significant differences in eradication rates for both intention to treat population (70.2%, 95% confidence interval [CI]: 66.3-74.1% vs. 71.8%, 95% CI: 61.8-81.7%, for ST and BST, respectively, p>0.05) and per protocol population (74.6%, 95% CI: 63.2-85.8% vs. 73.7%, 95% CI: 63.9-83.5% for ST and BST, respectively, p>0.05). Despite the undeniable effect of bismuth, there may be several possible reasons of unsatisfactory eradication success. Drug administration time, coadministration of other drugs, possible H. pylori resistance to bismuth may affect the eradication success. The addition of bismuth subcitrate to ST regimen does not provide significant increase in eradication rates.

  10. Experimental Study of Disruption of Columnar Grains During Rapid Solidification in Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Manogharan, Guha; Yelamanchi, Bharat; Aman, Ronald; Mahbooba, Zaynab

    2016-03-01

    Over the years, many studies have been conducted to study and analyze the grain structures of metal alloys during additive manufacturing to improve mechanical properties. In particular, columnar grains are observed predominantly during rapid solidification of molten metal. This leads to lower mechanical properties and requires expensive secondary heat-treatment processes. This study is aimed at disrupting the formation of columnar grain growth during rapid solidification using ultrasonic vibration and analyzes the effects on grain structure and mechanical properties. A gas-metal arc welder mounted on a Rep-Rap-based low-cost metal 3 Dimension printer was used to deposit ER70S-6 mild steel layers on a plate. A contact-type ultrasonic transducer with a control system to vary the frequency and power of the vibration was used. The effects of ultrasonic vibration were determined from the statistical analysis of microstructure and micro-indentation techniques on the deposited layer and heat-affected zone. It was found that both frequency and interaction between frequency and power had significant impact on the refinement of average grain size up to 10.64% and increased the number of grains by approximately 41.78%. Analysis of micro-indentation tests showed that there was an increase of approximately 14.30% in micro-hardness due to the applied frequency during rapid solidification. A pole diagram shows that application of vibration causes randomization of grain orientation. Along with the results from this study, further efforts in modeling and experimentation of multi-directional vibrations would lead to a better understanding of disrupting columnar grains in applications that use mechanical vibrations, such as welding, directed energy deposition, brazing, etc.

  11. Percutaneous Dorsal Instrumentation of Vertebral Burst Fractures: Value of Additional Percutaneous Intravertebral Reposition—Cadaver Study

    PubMed Central

    Krüger, Antonio; Schmuck, Maya; Noriega, David C.; Ruchholtz, Steffen; Baroud, Gamal; Oberkircher, Ludwig

    2015-01-01

    Purpose. The treatment of vertebral burst fractures is still controversial. The aim of the study is to evaluate the purpose of additional percutaneous intravertebral reduction when combined with dorsal instrumentation. Methods. In this biomechanical cadaver study twenty-eight spine segments (T11-L3) were used (male donors, mean age 64.9 ± 6.5 years). Burst fractures of L1 were generated using a standardised protocol. After fracture all spines were allocated to four similar groups and randomised according to surgical techniques (posterior instrumentation; posterior instrumentation + intravertebral reduction device + cement augmentation; posterior instrumentation + intravertebral reduction device without cement; and intravertebral reduction device + cement augmentation). After treatment, 100000 cycles (100–600 N, 3 Hz) were applied using a servohydraulic loading frame. Results. Overall anatomical restoration was better in all groups where the intravertebral reduction device was used (p < 0.05). In particular, it was possible to restore central endplates (p > 0.05). All techniques decreased narrowing of the spinal canal. After loading, clearance could be maintained in all groups fitted with the intravertebral reduction device. Narrowing increased in the group treated with dorsal instrumentation. Conclusions. For height and anatomical restoration, the combination of an intravertebral reduction device with dorsal instrumentation showed significantly better results than sole dorsal instrumentation. PMID:26137481

  12. Evaluating the addition of positive reinforcement for learning a frightening task: a pilot study with horses.

    PubMed

    Heleski, Camie; Bauson, Laura; Bello, Nora

    2008-01-01

    Horse training often relies upon negative reinforcement (NR). This study tested the hypothesis that adding positive reinforcement (PR) to NR would enhance learning in horses (n = 34) being taught to walk over a tarp (novel/typically frightening task). Subjects were Arabians, and the same person handled all of them. This person handled half "traditionally" (NR only)--that is, halter/lead were pulled; when horse stepped forward, pressure was released; process repeated until criterion met (horse crossed the tarp with little/no obvious anxiety). The same person handled the other half traditionally--but with addition of PR < food + verbal praise > (NR + PR). Subjects "failed" the task if they refused to walk onto the tarp after 10 min. Nine horses failed; 6 of 9 failures were from NR only--no significant difference detected (p = .41). The study detected no difference in time to first crossing of the tarp (p = .30) or total time to achieve calmness criterion (p = .67). Overall, adding PR did not significantly enhance learning this task. However, there were practical implications--adding PR made the task safer/less fatiguing for the handler.

  13. Synthesis, Characterization, Molecular Modeling, and DNA Interaction Studies of Copper Complex Containing Food Additive Carmoisine Dye.

    PubMed

    Shahabadi, Nahid; Akbari, Alireza; Jamshidbeigi, Mina; Khodarahmi, Reza

    2016-06-02

    A copper complex of carmoisine dye; [Cu(carmoisine)2(H2O)2]; was synthesized and characterized by using physico-chemical and spectroscopic methods. The binding of this complex with calf thymus (ct) DNA was investigated by circular dichroism, absorption studies, emission spectroscopy, and viscosity measurements. UV-vis results confirmed that the Cu complex interacted with DNA to form a ground-state complex and the observed binding constant (2× 10(4) M(-1)) is more in keeping with the groove bindings with DNA. Furthermore, the viscosity measurement result showed that the addition of complex causes no significant change on DNA viscosity and it indicated that the intercalation mode is ruled out. The thermodynamic parameters are calculated by van't Hoff equation, which demonstrated that hydrogen bonds and van der Waals interactions played major roles in the reaction. The results of circular dichroism (CD) suggested that the complex can change the conformation of DNA from B-like form toward A-like conformation. The cytotoxicity studies of the carmoisine dye and its copper complex indicated that both of them had anticancer effects on HT-29 (colon cancer) cell line and they may be new candidates for treatment of the colon cancer.

  14. An fMRI study of magnitude comparison and exact addition in children.

    PubMed

    Meintjes, Ernesta M; Jacobson, Sandra W; Molteno, Christopher D; Gatenby, J Christopher; Warton, Christopher; Cannistraci, Christopher J; Gore, John C; Jacobson, Joseph L

    2010-04-01

    By contrast to the adult literature, in which a consistent parietofrontal network for number processing has been identified, the data from studies of number processing in children have been less consistent, probably due to differences in study design and control conditions. Number processing was examined using functional magnetic resonance imaging in 18 right-handed children (8-12 years) from the Cape Coloured community in Cape Town, South Africa, using Proximity Judgment and Exact Addition (EA) tasks. The findings were consistent with the hypothesis that, as in adults, the anterior horizontal intraparietal sulcus (HIPS) plays a major role in the representation and manipulation of quantity in children. The posterior medial frontal cortex, believed to be involved in performance monitoring in more complex arithmetic manipulations in adults, was extensively activated even for relatively simple symbolic number processing in the children. Other areas activated to a greater degree in the children included the left precentral sulcus, which may mediate number knowledge and, for EA, the head of the caudate nucleus, which is part of a fronto-subcortical circuit involved in the behavioral execution of sequences. Two regions that have been linked to number processing in adults - the angular gyrus and posterior superior parietal lobule - were not activated in the children. The data are consistent with the inference that although the functional specialization of the anterior HIPS may increase as symbolic number processing becomes increasingly automatic, this region and other elements of the parietofrontal network identified in adults are already reliably and robustly activated by middle childhood.

  15. Neural network modelling and dynamical system theory: are they relevant to study the governing dynamics of association football players?

    PubMed

    Dutt-Mazumder, Aviroop; Button, Chris; Robins, Anthony; Bartlett, Roger

    2011-12-01

    Recent studies have explored the organization of player movements in team sports using a range of statistical tools. However, the factors that best explain the performance of association football teams remain elusive. Arguably, this is due to the high-dimensional behavioural outputs that illustrate the complex, evolving configurations typical of team games. According to dynamical system analysts, movement patterns in team sports exhibit nonlinear self-organizing features. Nonlinear processing tools (i.e. Artificial Neural Networks; ANNs) are becoming increasingly popular to investigate the coordination of participants in sports competitions. ANNs are well suited to describing high-dimensional data sets with nonlinear attributes, however, limited information concerning the processes required to apply ANNs exists. This review investigates the relative value of various ANN learning approaches used in sports performance analysis of team sports focusing on potential applications for association football. Sixty-two research sources were summarized and reviewed from electronic literature search engines such as SPORTDiscus, Google Scholar, IEEE Xplore, Scirus, ScienceDirect and Elsevier. Typical ANN learning algorithms can be adapted to perform pattern recognition and pattern classification. Particularly, dimensionality reduction by a Kohonen feature map (KFM) can compress chaotic high-dimensional datasets into low-dimensional relevant information. Such information would be useful for developing effective training drills that should enhance self-organizing coordination among players. We conclude that ANN-based qualitative analysis is a promising approach to understand the dynamical attributes of association football players.

  16. The relevance to humans of animal models for inhalation studies of cancer in the nose and upper airways.

    PubMed

    DeSesso, J M

    1993-09-01

    While nasal cancer is relatively rare among the general population, workers in the nickel refining, leather manufacturing, and furniture building industries exhibit increased incidences of nasal cancer. To investigate the causes of nasal cancer and to design ameliorative strategies, an appropriate animal model for the human upper respiratory regions is required. The present report describes, compares, and assesses the anatomy and physiology of the nasal passages and upper airways of humans, rats, and monkeys for the purpose of determining a relevant animal model in which to investigate potential causes of nasal cancer. Based on the mode of breathing, overall geometry of the nasal passages, relative nasal surface areas, proportions of nasal surfaces lined by various epithelia, mucociliary clearance patterns, and inspiratory airflow routes, the rat, which is very different from humans, is a poor model. In contrast, the monkey exhibits many similarities to humans. Although the monkey does differ from humans in that it exhibits a more rapid respiratory rate, smaller minute and tidal volumes, larger medial turbinate, and a vestibular wing that creates an anterior vortex during inspiration, it offers a more appropriate model for studying the toxic effects of inhaled substances on the nasal passages and extrapolating the findings to humans.

  17. Divergent neuroactive steroid responses to stress and ethanol in rat and mouse strains: Relevance for human studies

    PubMed Central

    Porcu, Patrizia; Morrow, A. Leslie

    2014-01-01

    Rationale Neuroactive steroids are endogenous or synthetic steroids that rapidly alter neuronal excitability via membrane receptors, primarily GABAA receptors. Neuroactive steroids regulate many physiological processes including hypothalamic-pituitary-adrenal (HPA) axis function, ovarian cycle, pregnancy, aging, and reward. Moreover, alterations in neuroactive steroid synthesis are implicated in several neuropsychiatric disorders. Objectives This review will summarize the pharmacological properties and physiological regulation of neuroactive steroids, with a particular focus on divergent neuroactive steroid responses to stress and ethanol in rats, mice and humans. Results GABAergic neuroactive steroids exert a homeostatic regulation of the HPA axis in rats and humans, whereby the increase in neuroactive steroid levels following acute stress counteracts HPA axis hyperactivity and restores homeostasis. In contrast, in C57BL/6J mice, acute stress decreases neurosteroidogenesis and neuroactive steroids exert paradoxical excitatory effects upon the HPA axis. Rats, mice and humans also differ in the neuroactive steroid responses to ethanol. Genetic variation in neurosteroidogenesis may explain the different neuroactive steroid responses to stress or ethanol. Conclusions Rats and mouse strains show divergent effects of stress and ethanol on neuroactive steroids in both plasma and brain. The study of genetic variation in the various processes that determine neuroactive steroids levels as well as their effects on cell signaling may underlie these differences and may play a relevant role for the potential therapeutic benefits of neuroactive steroids. PMID:24770626

  18. The organotypic multicellular spheroid is a relevant three-dimensional model to study adenovirus replication and penetration in human tumors in vitro.

    PubMed

    Grill, Jacques; Lamfers, Martine L M; van Beusechem, Victor W; Dirven, Clemens M; Pherai, D Shareen; Kater, Mathijs; Van der Valk, Paul; Vogels, Ronald; Vandertop, W Peter; Pinedo, Herbert M; Curiel, David T; Gerritsen, Winald R

    2002-11-01

    The use of adenoviruses for gene transfer and as oncolytic agents is currently receiving widespread attention. As specific constraints to adenovirus distribution and spread cannot be studied in cell cultures, there is a need for an in vitro three-dimensional (3D) model mimicking the in vivo biology of tumors. We studied the interactions between tumor and adenoviruses using multicellular spheroids grown from primary brain tumor material. Using beta-galactosidase and luciferase reporter genes expressed by replication-defective adenoviruses, we showed that infection was restricted to the first layer of cells. Using a replication-competent adenovirus expressing the luciferase gene, we showed that transgene expression in the spheroid was considerably enhanced and that viral spreading deep into the 3D structure took place. In addition, a tetrazolium salt-based metabolic assay could be used to compare the oncolytic activity of different concentrations of replication-competent adenoviruses. We can conclude that organotypic spheroids offer a versatile in vitro system for studying distribution, spread, and oncolysis by adenoviruses in a clinically relevant model.

  19. Theoretical study of ignition reactions of linear symmetrical monoethers as potential diesel fuel additives: DFT calculations

    NASA Astrophysics Data System (ADS)

    Marrouni, Karim El; Abou-Rachid, Hakima; Kaliaguine, Serge

    This work investigates the chemical reactivity of four linear symmetrical monoethers with molecular oxygen. Such oxygenated compounds may be considered as potential diesel fuel additives in order to reduce the ignition delay in diesel fuel engines. For this purpose, a kinetic study is proposed to clarify the relation between the molecular structure of the fuel molecule and its ignition properties. To this end, DFT calculations were performed for these reactions using B3LYP/6-311G(d,p) and BH&HLYP/6-311G(d,p) to determine structures, energies, and vibrational frequencies of stationary points as well as activated complexes involved in each gas-phase combustion initiation reaction of the monoethers CH3OCH3, C2H5OC2H5, C3H7OC3H7, or C4H9OC4H9 with molecular oxygen. This theoretical kinetic study was carried out using electronic structure results and the transition state theory, to assess the rate constants for all studied combustion reactions. As it has been shown in our previous work [Abou-Rachid et al., J Mol Struct (Theochem) 2003, 621, 293], the cetane number (CN) of a pure organic molecule depends on the initiation rate of its homogeneous gas-phase reaction with molecular oxygen. Indeed, the calculated initiation rate constants of the H-abstraction process of linear monoethers with O2 show a very good correlation with experimental CN data of these pure compounds at T D 1,000 K. This temperature is representative of the operating conditions of a diesel fuel engine.0

  20. Experimental study of enhanced heat transfer by addition of CuO nanoparticle

    NASA Astrophysics Data System (ADS)

    Jesumathy, Stella; Udayakumar, M.; Suresh, S.

    2012-06-01

    An energy storage system has been designed to study the thermal characteristics of paraffin wax with an embedded nano size copper oxide (CuO) particle. This paper presents studies conducted on phase transition times, heat fraction as well as heat transfer characteristics of paraffin wax as phase change material (PCM) embedded with CuO nanoparticles. 40 nm mean size CuO particles of 2, 5 and 10% by weight were dispersed in PCM for this study. Experiments were performed on a heat exchanger with 1.5-10 l/min of heat transfer fluid (HTF) flow. Time-based variations of the temperature distributions are revealed from the results of observations of melting and solidification curves. The results strongly suggested that the thermal conductivity enhances 6, 6.7 and 7.8% in liquid state and in dynamic viscosity it enhances by 5, 14 and 30% with increasing mass fraction of the CNEPs. The thermal conductivity ratio of the composites can be augmented by a factor up to 1.3. The heat transfer coefficient during solidification increased about 78% for the maximum flow rate. The analysis of experimental results reveals that the addition of copper oxide nanoparticles to the paraffin wax enhances both the conduction and natural convection very effectively in composites and in paraffin wax. The paraffin wax-based composites have great potential for energy storage applications like industrial waste heat recovery, solar thermal applications and solar based dynamic space power generation with optimal fraction of copper oxide nanoparticles.

  1. The Relevance of Literature.

    ERIC Educational Resources Information Center

    Dunham, L. L.

    1971-01-01

    The "legacy" of the humanities is discussed in terms of relevance, involvement, and other philosophical considerations. Reasons for studying foreign literature in language classes are developed in the article. Comment is also made on attitudes and ideas culled from the writings of Clifton Fadiman, Jean Paul Sartre, and James Baldwin. (RL)

  2. Is Information Still Relevant?

    ERIC Educational Resources Information Center

    Ma, Lia

    2013-01-01

    Introduction: The term "information" in information science does not share the characteristics of those of a nomenclature: it does not bear a generally accepted definition and it does not serve as the bases and assumptions for research studies. As the data deluge has arrived, is the concept of information still relevant for information…

  3. Beyond the Call of Duty: A Qualitative Study of Teachers' Additional Responsibilities Related to Sexuality Education

    ERIC Educational Resources Information Center

    Eisenberg, Marla E.; Madsen, Nikki; Oliphant, Jennifer A.; Resnick, Michael

    2011-01-01

    Seven focus groups were conducted with sexuality educators in Minnesota to explore ways that teaching sexuality education differs from teaching other health education content and to determine if additional supports or resources are needed for sexuality educators. Teachers described many specific additional responsibilities or concerns related to…

  4. Additional Language Teaching within the International Baccalaureate Primary Years Programme: A Comparative Study

    ERIC Educational Resources Information Center

    Lebreton, Marlène

    2014-01-01

    The International Baccalaureate Primary Years Programme supports the learning of languages and cultures, but the role of the additional language within this programme is often unclear. There remains a great variability in schools regarding the frequency of lessons and the way that the additional language is taught within the Primary Years…

  5. On the Physical Relevance of the Study of gamma* gamma -> pi pi at small t and large Q2

    SciTech Connect

    Lansberg, J.P.; Pire, B.; Szymanowski, L.; /Warsaw, Inst. Nucl. Studies

    2010-08-26

    We discuss the relevance of a dedicated measurement of exclusive production of a pair of neutral pions in a hard {gamma}*{gamma} scattering at small momentum transfer. In this case, the virtuality of one photon provides us with a hard scale in the process, enabling us to perform a QCD calculation of this reaction rate using the concept of Transition Distribution Amplitudes (TDA). Those are related by sum rules to the pion axial form factor F{sub A}{sup {pi}} and, as a direct consequence, a cross-section measurement of this process at intense beam electron-positron colliders such as CLEO, KEK-B and PEP-II, or Super-B would provide us with a unique measurement of the neutral pion axial form factor F{sub A}{sup {pi}0} at small scale. We believe that our models for the photon to meson transition distribution amplitudes are sufficiently constrained to give reasonable orders of magnitude for the estimated cross sections. Cross sections are large enough for quantitative studies to be performed at high luminosity e{sup +}e{sup -} colliders. After verifying the scaling and the {phi} independence of the cross section, one should be able to measure these new hadronic matrix elements, and thus open a new gate to the understanding of the hadronic structure. In particular, we argued here that the study of {gamma}*{gamma} {yields} {pi}{sup 0}{pi}{sup 0} in the TDA regime could provide with a unique experimental measurement of the {pi}{sup 0} axial form factor.

  6. Relevance of TNBS-Colitis in Rats: A Methodological Study with Endoscopic, Histologic and Transcriptomic Characterization and Correlation to IBD

    PubMed Central

    Brenna, Øystein; Furnes, Marianne W.; Drozdov, Ignat; van Beelen Granlund, Atle; Flatberg, Arnar; Sandvik, Arne K.; Zwiggelaar, Rosalie T. M.; Mårvik, Ronald; Nordrum, Ivar S.; Kidd, Mark; Gustafsson, Björn I.

    2013-01-01

    Background Rectal instillation of trinitrobenzene sulphonic acid (TNBS) in ethanol is an established model for inflammatory bowel disease (IBD). We aimed to 1) set up a TNBS-colitis protocol resulting in an endoscopic and histologic picture resembling IBD, 2) study the correlation between endoscopic, histologic and gene expression alterations at different time points after colitis induction, and 3) compare rat and human IBD mucosal transcriptomic data to evaluate whether TNBS-colitis is an appropriate model of IBD. Methodology/Principal Findings Five female Sprague Daley rats received TNBS diluted in 50% ethanol (18 mg/0.6 ml) rectally. The rats underwent colonoscopy with biopsy at different time points. RNA was extracted from rat biopsies and microarray was performed. PCR and in situ hybridization (ISH) were done for validation of microarray results. Rat microarray profiles were compared to human IBD expression profiles (25 ulcerative colitis Endoscopic score demonstrated mild to moderate colitis after three and seven days, but declined after twelve days. Histologic changes corresponded with the endoscopic appearance. Over-represented Gene Ontology Biological Processes included: Cell Adhesion, Immune Response, Lipid Metabolic Process, and Tissue Regeneration. IL-1α, IL-1β, TLR2, TLR4, PRNP were all significantly up-regulated, while PPARγ was significantly down-regulated. Among genes with highest fold change (FC) were SPINK4, LBP, ADA, RETNLB and IL-1α. The highest concordance in differential expression between TNBS and IBD transcriptomes was three days after colitis induction. ISH and PCR results corresponded with the microarray data. The most concordantly expressed biologically relevant pathways included TNF signaling, Cell junction organization, and Interleukin-1 processing. Conclusions/Significance Endoscopy with biopsies in TNBS-colitis is useful to follow temporal changes of inflammation visually and histologically, and to acquire tissue for gene

  7. Single and combined toxicity of pharmaceuticals at environmentally relevant concentrations in Daphnia magna--a multigenerational study.

    PubMed

    Dietrich, Sabine; Ploessl, Florian; Bracher, Franz; Laforsch, Christian

    2010-03-01

    Pharmaceuticals are continuously discharged into the environment, resulting in the chronic exposure of aquatic organisms to these compounds. In this multigenerational study, we examined the influence of four pharmaceuticals (carbamazepine (CBZ), diclofenac (DIC), 17alpha-ethinylestradiol (EE2) and metoprolol (MET)) as single substances and as a drug mixture at environmentally relevant concentrations on life-history and morphological parameters over six generations of the cladoceran Daphnia magna. Detectable effects of the used pharmaceuticals occured in the first observed generation, followed by an acclimation period and a recurrence of drug effects in later generations: daphnids exposed to MET were affected by the pharmaceutical, resulting in a decreased body length at first reproduction in the generations F0, F3 and F4 and in a reduced number of offspring in the generations F0 and F4. Similar effects were observed in daphnids exposed to EE2. DIC delayed age at first reproduction in the F0 and F2 generations and increased the body length of neonates in the generations F1 and F5. Daphnids exposed to CBZ showed a delay in the age at first reproduction for the F0 generation only. The drug mixture reduced the age at first reproduction of daphnids in the F0 and F2 generation and increased the body length at first reproduction in the generations F0 and F3. Neither the single drugs nor the pharmaceutical mixture influenced the successive generations of D. magna in a steady way. Thus, multigenerational studies are necessary to prevent insufficient assessments on the impact of pharmaceuticals in aquatic ecosystems.

  8. Meiofaunal and bacterial community response to diesel additions in a microcosm study.

    PubMed

    Lindgren, J Fredrik; Hassellöv, Ida-Maja; Dahllöf, Ingela

    2012-03-01

    Effects of low PAH-containing diesel were studied in a 60-day microcosm experiment at PAH concentrations 130, 1300 and 13,000μg/kg sediment. Nutrient fluxes, potential nitrification and meiofaunal community composition were analysed at three time points. Changed ∑NOx-fluxes indicated reduced sediment nitrification in Medium and High with time, in agreement with lowered potential nitrification rates in all treatments. Reduction in silicate and phosphate fluxes over time suggested severe effects on activity of meiofauna. Reduced activity increased the anoxic sediment layer, which could have contributed to the changed ∑NOx-fluxes. There were significant differences in meiofaunal community composition after 30 and 60days in Medium and High. Changes were due to increasing numbers of harpacticoids and the foraminiferan group Rotaliina, as well as decreasing numbers of Nematodes and the foraminiferan group Reophax. In spite of the low PAH-level, small additions of this diesel can still have pronounced effects on meiofaunal and bacterial communities.

  9. Experimental study of combustion characteristics of nanoscale metal and metal oxide additives in biofuel (ethanol)

    PubMed Central

    2011-01-01

    An experimental investigation of the combustion behavior of nano-aluminum (n-Al) and nano-aluminum oxide (n-Al2O3) particles stably suspended in biofuel (ethanol) as a secondary energy carrier was conducted. The heat of combustion (HoC) was studied using a modified static bomb calorimeter system. Combustion element composition and surface morphology were evaluated using a SEM/EDS system. N-Al and n-Al2O3 particles of 50- and 36-nm diameters, respectively, were utilized in this investigation. Combustion experiments were performed with volume fractions of 1, 3, 5, 7, and 10% for n-Al, and 0.5, 1, 3, and 5% for n-Al2O3. The results indicate that the amount of heat released from ethanol combustion increases almost linearly with n-Al concentration. N-Al volume fractions of 1 and 3% did not show enhancement in the average volumetric HoC, but higher volume fractions of 5, 7, and 10% increased the volumetric HoC by 5.82, 8.65, and 15.31%, respectively. N-Al2O3 and heavily passivated n-Al additives did not participate in combustion reactively, and there was no contribution from Al2O3 to the HoC in the tests. A combustion model that utilized Chemical Equilibrium with Applications was conducted as well and was shown to be in good agreement with the experimental results. PMID:21711760

  10. A theoretical study of wave dispersion and thermal conduction for HMX/additive interfaces

    NASA Astrophysics Data System (ADS)

    Long, Yao; Chen, Jun

    2014-04-01

    The wave dispersion rule for non-uniform material is useful for ultrasonic inspection and engine life prediction, and also is key in achieving an understanding of the energy dissipation and thermal conduction properties of solid material. On the basis of linear response theory and molecular dynamics, we derive a set of formulas for calculating the wave dispersion rate of interface systems, and study four kinds of interfaces inside plastic bonded explosives: HMX/{HMX, TATB, F2312, F2313}. (HMX: octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine; TATB: 1,3,5-triamino-2,4,6-trinitrobenzene; F2312, F2313: fluoropolymers). The wave dispersion rate is obtained over a wide frequency range from kHz to PHz. We find that at low frequency, the rate is proportional to the square of the frequency, and at high frequency, the rate couples with the molecular vibration modes at the interface. By using the results, the thermal conductivities of HMX/additive interfaces are derived, and a physical model is built for describing the total thermal conductivity of mixture explosives, including HMX multi-particle systems and {TATB, F2312, F2313}-coated HMX.

  11. Tackling missing data in community health studies using additive LS-SVM classifier.

    PubMed

    Wang, Guanjin; Deng, Zhaohong; Choi, Kup-Sze

    2016-12-01

    Missing data is a common issue in community health and epidemiological studies. Direct removal of samples with missing data can lead to reduced sample size and information bias, which deteriorates the significance of the results. While data imputation methods are available to deal with missing data, they are limited in performance and could introduce noises into the dataset. Instead of data imputation, a novel method based on additive least square support vector machine (LS-SVM) is proposed in this paper for predictive modeling when the input features of the model contain missing data. The method also determines simultaneously the influence of the features with missing values on the classification accuracy using the fast leave-one-out cross-validation strategy. The performance of the method is evaluated by applying it to predict the quality of life (QOL) of elderly people using health data collected in the community. The dataset involves demographics, socioeconomic status, health history and the outcomes of health assessments of 444 community-dwelling elderly people, with 5% to 60% of data missing in some of the input features. The QOL is measured using a standard questionnaire of the World Health Organization. Results show that the proposed method outperforms four conventional methods for handling missing data - case deletion, feature deletion, mean imputation and K-nearest neighbor imputation, with the average QOL prediction accuracy reaching 0.7418. It is potentially a promising technique for tackling missing data in community health research and other applications.

  12. Interaction of fluorescence dyes with 5-fluorouracil: A photoinduced electron transfer study in bulk and biologically relevant water

    NASA Astrophysics Data System (ADS)

    Kuchlyan, Jagannath; Banik, Debasis; Kundu, Niloy; Roy, Arpita; Sarkar, Nilmoni

    2014-10-01

    The interactions of widely used chemotherapeutic drug, 5-fluorouracil (5FU) with coumarin dyes have been investigated for the first time using steady-state and time-resolved fluorescence spectroscopic measurements. The fluorescence quenching along with the decrease in lifetimes of excited state of coumarin derivatives with gradual addition of 5FU is explained by photoinduced electron transfer (PET) mechanism. Our studies were performed in bulk water and confined water of AOT (aerosol OT) reverse micelle to investigate the effect of confinement on PET dynamics. The feasibility of PET reaction for coumarin-5FU systems is investigated calculating the standard free energy changes using the Rehm-Weller equation.

  13. Photodegradation behaviour of sethoxydim and its comercial formulation Poast(®) under environmentally-relevant conditions in aqueous media. Study of photoproducts and their toxicity.

    PubMed

    Sevilla-Morán, Beatriz; Calvo, Luisa; López-Goti, Carmen; Alonso-Prados, José L; Sandín-España, Pilar

    2017-02-01

    Photolysis is an important route for the abiotic degradation of many pesticides. However, the knowledge of the photolytic behaviour of these compounds and their commercial formulations under environmentally-relevant conditions are limited. The present study investigated the importance of photochemical processes on the persistence and fate of the herbicide sethoxydim and its commercial formulation Poast(®) in aqueous media. Moreover, the effect of important natural water substances (nitrate, calcium, and ferric ions) on the photolysis of the herbicide was also studied. The results showed that additives existing in the commercial formulation Poast(®) accelerated the rate of photolysis of sethoxydim by a factor of 3. On the contrary, the presence of nitrate and calcium ions had no effect on the photodegradation rate while ferric ions resulted in an important decrease in the half-life of sethoxydim possibly due to the formation of a complex. Different transformation products were identified in the course of sethoxydim irradiation and the effect of experimental conditions on their concentrations was investigated. Finally, Microtox(®) test revealed that aqueous solutions of sethoxydim photoproducts increased the toxicity to the bacteria Vibrio fischeri.

  14. Culturally relevant treatment services for perinatal depression in socio-economically disadvantaged women: The design of the MOMCare study*

    PubMed Central

    Grote, Nancy K.; Katon, Wayne J.; Lohr, Mary Jane; Carson, Kathy; Curran, Mary; Galvin, Erin; Russo, Joan E.; Gregory, Marilyn

    2014-01-01

    Background Depression during pregnancy has been demonstrated to be predictive of low birthweight, prematurity, and postpartum depression. These adverse outcomes potentially have lasting effects on maternal and child well-being. Socio-economically disadvantaged women are twice as likely as middle-class women to meet diagnostic criteria for antenatal major depression (MDD), but have proven difficult to engage and retain in treatment. Collaborative care treatment models for depression have not been evaluated for racially/ethnically diverse, pregnant women on Medicaid receiving care in a public health system. This paper describes the design, methodology, culturally relevant enhancements, and implementation of a randomized controlled trial of depression care management compared to public health Maternity Support Services(MSS). Methods Pregnant, public health patients, ≥18 years with a likely diagnosis of MDD or dysthymia, measured respectively by the Patient Health Questionnaire-9(PHQ-9) or the Mini-International Neuropsychiatric Interview(MINI), were randomized to the intervention or to public health MSS. The primary outcome was reduction in depression severity from baseline during pregnancy to 18-months post-baseline(one-year postpartum). Baseline Results 168 women with likely MDD (96.4%) and/or dysthymia (24.4%) were randomized. Average age was 27.6 years and gestational age was 22.4 weeks; 58.3% racial/ethnic minority; 71.4% unmarried; 22% no high school degree/GED; 65.3% unemployed; 42.1% making ≤$10,000 annually; 80.4% having recurrent depression; 64.6% PTSD, and 72% an unplanned pregnancy. Conclusions A collaborative care team, including a psychiatrist, psychologist, project manager, and 3 social workers, met weekly, collaborated with the patients' obstetrics providers, and monitored depression severity using an electronic tracking system. Potential sustainability of the intervention within a public health system requires further study. PMID:25016216

  15. Does Addition of Propolis to Glass Ionomer Cement Alter its Physicomechanical Properties? An In Vitro Study.

    PubMed

    Subramaniam, P; Girish Babu, K L; Neeraja, G; Pillai, S

    Propolis is a natural resinous substance produced by honey bees. The antimicrobial effects of glass ionomer cement have been shown to improve with the addition of propolis; however its effect on the physicomechanical properties of the cement is not known.

  16. Comparative Studies of Cathodically-Promoted and Base-Catalyzed Michael Addition Reactions of Levoglucosenone.

    PubMed

    Samet, Alexander V.; Niyazymbetov, Murat E.; Semenov, Victor V.; Laikhter, Andrei L.; Evans, Dennis H.

    1996-12-13

    Regioselective Michael addition of nitro and heterocyclic compounds to levoglucosenone, 1, is effectively catalyzed by amines and also by cathodic electrolysis. In comparison to the base-catalyzed reaction, it was found that under electrochemical conditions the reaction proceeds under milder conditions and with higher yields. Cathodically-initiated Michael addition of thiols to levoglucosenone using small currents produces the previously unknown threo addition product in several instances. The normal erythro isomer, identified as the kinetic product, tends to be formed when large currents are used. In contrast, slow, low current electrolyses promote equilibration of the two forms so that erythro can be converted to threo by the retro reaction and readdition. Addition of 2-naphthalenethiol to (R)-(+)-apoverbenone is also reported.

  17. Study of metal whiskers growth and mitigation technique using additive manufacturing

    NASA Astrophysics Data System (ADS)

    Gullapalli, Vikranth

    For years, the alloy of choice for electroplating electronic components has been tin-lead (Sn-Pb) alloy. However, the legislation established in Europe on July 1, 2006, required significant lead (Pb) content reductions from electronic hardware due to its toxic nature. A popular alternative for coating electronic components is pure tin (Sn). However, pure tin has the tendency to spontaneously grow electrically conductive Sn whisker during storage. Sn whisker is usually a pure single crystal tin with filament or hair-like structures grown directly from the electroplated surfaces. Sn whisker is highly conductive, and can cause short circuits in electronic components, which is a very significant reliability problem. The damages caused by Sn whisker growth are reported in very critical applications such as aircraft, spacecraft, satellites, and military weapons systems. They are also naturally very strong and are believed to grow from compressive stresses developed in the Sn coating during deposition or over time. The new directive, even though environmentally friendly, has placed all lead-free electronic devices at risk because of whisker growth in pure tin. Additionally, interest has occurred about studying the nature of other metal whiskers such as zinc (Zn) whiskers and comparing their behavior to that of Sn whiskers. Zn whiskers can be found in flooring of data centers which can get inside electronic systems during equipment reorganization and movement and can also cause systems failure. Even though the topic of metal whiskers as reliability failure has been around for several decades to date, there is no successful method that can eliminate their growth. This thesis will give further insights towards the nature and behavior of Sn and Zn whiskers growth, and recommend a novel manufacturing technique that has potential to mitigate metal whiskers growth and extend life of many electronic devices.

  18. Chemostat Studies of TCE-Dehalogenating Anaerobic Consortia under Excess and Limited Electron Donor Addition

    NASA Astrophysics Data System (ADS)

    Semprini, L.; Azizian, M.; Green, J.; Mayer-Blackwell, K.; Spormann, A. M.

    2015-12-01

    Two cultures - the Victoria Strain (VS) and the Evanite Strain (EV), enriched with the organohalide respiring bacteria Dehalococcoides mccartyi - were grown in chemostats for more than 4 years at a mean cell residence time of 50 days. The slow doubling rate represents growth likely experienced in the subsurface. The chemostats were fed formate as an electron donor and trichloroethene (TCE) as the terminal electron acceptor. Under excess formate conditions, stable operation was observed with respect to TCE transformation, steady-state hydrogen (H2) concentrations (40 nM), and the structure of the dehalogenating community. Both cultures completely transformed TCE to ethene, with minor amounts of vinyl chloride (VC) observed, along with acetate formation. When formate was limited, TCE was transformed incompletely to ethene (40-60%) and VC (60- 40%), and H2 concentrations ranged from 1 to 3 nM. The acetate concentration dropped below detection. Batch kinetic studies of TCE transformation with chemostat harvested cells found transformation rates of c-DCE and VC were greatly reduced when the cells were grown with limited formate. Upon increasing formate addition to the chemostats, from limited to excess, essentially complete transformation of TCE to ethene was achieved. The increase in formate was associated with an increase in H2 concentration and the production of acetate. Results of batch kinetic tests showed increases in transformation rates for TCE and c-DCE by factors of 3.5 and 2.5, respectively, while VC rates increased by factors of 33 to 500, over a six month period. Molecular analysis of chemostat samples is being performed to quantify the changes in copy numbers of reductase genes and to determine whether shifts in the strains of Dehalococcoides mccartyi where responsible for the observed rate increases. The results demonstrate the importance of electron donor supply for successful in-situ remediation.

  19. Breast size, thoracic kyphosis & thoracic spine pain - association & relevance of bra fitting in post-menopausal women: a correlational study

    PubMed Central

    2013-01-01

    Background Menopause would seem to exist as a period of accelerated changes for women and their upper torso mechanics. Whether these anthropometric changes reflect changes in pain states remains unclear. Plausible mechanisms of pain exist for the independent and combined effect of increasing breast size and thoracic kyphosis. Bra fit has the potential to change when the anthropometric measures (chest circumference and bust circumference) used to determine bra size change, such as postmenopausally. Identifying an association between breast size, thoracic kyphosis and thoracic spine pain in postmenopausal women and identifying the relevance of bra fit to this association may be of importance to the future management and education of post-menopausal women presenting clinically with thoracic spine pain. Methods A cross-sectional study design. Fifty-one postmenopausal bra-wearing women were recruited. Measures included breast size (Triumph International), thoracic kyphosis (flexible curve), bra fitted (Y/N) and pain (Short Form McGill Pain Questionnaire) and tenderness on palpation (posteroanterior pressure testing). These measures were collected in one session at a physiotherapy clinic. Results The majority of the women in this study were overweight or obese and wearing an incorrect sized bra. Pain was significantly related to breast size, body weight and BMI at mid thoracic levels (T7-8). In contrast self-reported thoracic pain was not correlated with age or index of kyphosis (thoracic kyphosis). Women with thoracic pain were no more likely to have their bra professionally fitted whereas women with a higher BMI and larger breasts were more likely to have their bra professionally fitted. Conclusion The findings of this study show that larger breasts and increased BMI are associated with thoracic pain in postmenopausal women. This is unrelated to thoracic kyphosis. Increasing breast size and how a bra is worn may have biomechanical implications for the loaded thoracic

  20. No relevant cardiac, pharmacokinetic or safety interactions between roflumilast and inhaled formoterol in healthy subjects: an open-label, randomised, actively controlled study

    PubMed Central

    2011-01-01

    Background Roflumilast is an oral, selective phosphodiesterase 4 inhibitor with anti-inflammatory effects in chronic obstructive pulmonary disease (COPD). The addition of roflumilast to long-acting bronchodilators improves lung function in patients with moderate-to-severe COPD. The present study investigated drug-drug interaction effects between inhaled formoterol and oral roflumilast. Methods This was a single-centre (investigational clinic), open, randomised, multiple-dose, parallel-group study. In Regimen A, healthy men were treated with roflumilast (500 μg tablet once daily; Day 2-18) and concomitant formoterol (24 μg twice daily; Day 12-18). In Regimen B, healthy men were treated with formoterol (24 μg twice daily; Day 2-18) and concomitant roflumilast (500 μg once daily; Day 9-18). Steady-state plasma pharmacokinetics of roflumilast, roflumilast N-oxide and/or formoterol (Cmax and AUC0-τ) as well as pharmacodynamics - blood pressure, transthoracic impedance cardiography (ZCG), 12-lead digital electrocardiography, peripheral blood eosinophils, and serum glucose and potassium concentrations - were evaluated through Day 1 (baseline), Day 8 (Regimen B: formoterol alone) or Day 11 (Regimen A: roflumilast alone), and Day 18 (Regimen A and B: roflumilast plus formoterol). Blood and urine samples were taken for safety assessment at screening, pharmacokinetic profiling days and Day 19. Adverse events were monitored throughout the study. Results Of the 27 subjects enrolled, 24 were evaluable (12 in each regimen). No relevant pharmacokinetic interactions occurred. Neither roflumilast nor formoterol were associated with significant changes in cardiovascular parameters as measured by ZCG, and these parameters were not affected during concomitant administration. Formoterol was associated with a slight increase in heart rate and a corresponding shortening of the QT interval, without changes in the heart rate-corrected QTc interval. There were small effects on the other

  1. 78 FR 68461 - Guidance for Industry: Studies To Evaluate the Utility of Anti-Salmonella Chemical Food Additives...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-14

    ... Anti- Salmonella Chemical Food Additives in Feeds; Request for Comments AGENCY: Food and Drug... revising the guidance entitled ``Guidance for Industry: Studies to Evaluate the Utility of Anti-Salmonella... Guidance for Industry: Studies to Evaluate the Utility of Anti-Salmonella Chemical Food Additives in...

  2. The Superior-Subordinate Relationship: A Preliminary Study of Downward Task-Relevant Confidential Information Disclosure in the Public Sector.

    ERIC Educational Resources Information Center

    Wanguri, Deloris McGee

    A questionnaire was administered to 94 first- and middle-level managers from 19 different state agencies in Texas in an effort to analyze conditions under which managers were most likely to disclose task-relevant confidential information to their subordinates. The open-ended items on the questionnaire investigated the types of confidential…

  3. Social Studies: Application Units. Course II, Teachers. Computer-Oriented Curriculum. REACT (Relevant Educational Applications of Computer Technology).

    ERIC Educational Resources Information Center

    Tecnica Education Corp., San Carlos, CA.

    This book is one of a series in Course II of the Relevant Educational Applications of Computer Technology (REACT) Project. It is designed to point out to teachers two of the major applications of computers in the social sciences: simulation and data analysis. The first section contains a variety of simulation units organized under the following…

  4. JournalMap: Discovering location-relevant knowledge from published studies for sustainable land use, preventing degradation, and restoring landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Finding relevant knowledge and information to prevent land degradation and support restoration has historically involved researchers working from their own knowledge, querying people they know, and tediously searching topical literature reviews.To address this need we created JournalMap (http://www....

  5. On Relevance Weight Estimation and Query Expansion.

    ERIC Educational Resources Information Center

    Robertson, S. E.

    1986-01-01

    A Bayesian argument is used to suggest modifications to the Robertson and Jones relevance weighting formula to accommodate the addition to the query of terms taken from the relevant documents identified during the search. (Author)

  6. Can ligand addition to soil enhance Cd phytoextraction? A mechanistic model study.

    PubMed

    Lin, Zhongbing; Schneider, André; Nguyen, Christophe; Sterckeman, Thibault

    2014-11-01

    Phytoextraction is a potential method for cleaning Cd-polluted soils. Ligand addition to soil is expected to enhance Cd phytoextraction. However, experimental results show that this addition has contradictory effects on plant Cd uptake. A mechanistic model simulating the reaction kinetics (adsorption on solid phase, complexation in solution), transport (convection, diffusion) and root absorption (symplastic, apoplastic) of Cd and its complexes in soil was developed. This was used to calculate plant Cd uptake with and without ligand addition in a great number of combinations of soil, ligand and plant characteristics, varying the parameters within defined domains. Ligand addition generally strongly reduced hydrated Cd (Cd(2+)) concentration in soil solution through Cd complexation. Dissociation of Cd complex ([Formula: see text]) could not compensate for this reduction, which greatly lowered Cd(2+) symplastic uptake by roots. The apoplastic uptake of [Formula: see text] was not sufficient to compensate for the decrease in symplastic uptake. This explained why in the majority of the cases, ligand addition resulted in the reduction of the simulated Cd phytoextraction. A few results showed an enhanced phytoextraction in very particular conditions (strong plant transpiration with high apoplastic Cd uptake capacity), but this enhancement was very limited, making chelant-enhanced phytoextraction poorly efficient for Cd.

  7. Case study: weight of evidence evaluation of the human health relevance of thiamethoxam-related mouse liver tumors.

    PubMed

    Pastoor, Timothy; Rose, Patrick; Lloyd, Sara; Peffer, Richard; Green, Trevor

    2005-07-01

    Thiamethoxam (CGA293343; 3-(2-chloro-thiazol-5-ylmethyl)-5-methyl-[1,3,5]oxadiazinan-4-ylidene-N-nitroamine) was shown to increase the incidence of mouse liver tumors in an 18-month study; however, thiamethoxam was not hepatocarcinogenic in rats. Thiamethoxam is not genotoxic, and, given the late life generation of mouse liver tumors, suggests a time-related progression of key hepatic events that leads to the tumors. These key events were identified in a series of studies of up to 50 weeks that showed the time-dependent evolution of relatively mild liver dysfunction within 10 weeks of dosing, followed by frank signs of hepatotoxicity after 20 weeks, leading to cellular attrition and regenerative hyperplasia. A metabolite, CGA330050, was identified as generating the mild hepatic toxicity, and another metabolite, CGA265307, exacerbated the initial toxicity by inhibiting inducible nitric oxide synthase. This combination of metabolite-generated hepatotoxicity and increase in cell replication rates is postulated as the mode of action for thiamethoxam-related mouse liver tumors. The relevance of these mouse-specific tumors to human health was assessed by using the framework and decision logic developed by ILSI-RSI. The postulated mode of action was tested against the Hill criteria and found to fulfill the comprehensive requirements of strength, consistency, specificity, temporality, dose-response, and the collective criteria of being a plausible mode of action that fits with known and similar modes of action. Whereas the postulated mode of action could theoretically operate in human liver, quantitation of the key metabolites in vivo and in vitro showed that mice, but not rats or humans, generate sufficient amounts of these metabolites to initiate the hepatic toxicity and consequent tumors. Indeed, rats fed 3000 ppm thiamethoxam for a lifetime did not develop hepatotoxicity or tumors. In conclusion, the coherence and extent of the database clearly demonstrates the mode of

  8. Combined NMR and quantum chemical studies on the interaction between trehalose and dienes relevant to the antioxidant function of trehalose.

    PubMed

    Oku, Kazuyuki; Kurose, Mayumi; Kubota, Michio; Fukuda, Shigeharu; Kurimoto, Masashi; Tujisaka, Yoshio; Okabe, Atsutoshi; Sakurai, Minoru

    2005-02-24

    In a previous study (Oku, K.; Watanabe, H.; Kubota, M.; Fukuda, S.; Kurimoto, M.; Tujisaka, Y.; Komori, M.; Inoue, Y.; Sakurai, M. J. Am. Chem. Soc. 2003, 125, 12739), we investigated the mechanism of the antioxidant function of trehalose against unsaturated fatty acids (UFAs) and revealed that the key factor relevant to the function is the formation of OH...pi and CH...O hydrogen bonds between trehalose and the cis double bonds of the UFA. Here, we investigate whether such intriguing interactions also occur between this sugar and cis double bonds in other unsaturated compounds. For this purpose, we selected various diene compounds (1,3-butadiene, 1,3-pentadiene, 1,4-pentadiene, and 2,5-heptadiene) as interaction partners. All NMR experiments performed, including 1H-1H NOESY measurements, indicated that trehalose selectively interacts with the cis-olefin proton pair in the above diene with a 1:1 stoichiometry, and the C-3 (C-3') and C-6' (C-6) sites of the sugar are responsible for the interaction. Similar interactions were not observed for the mixtures of the diene and other saccharides (neotrehalose, kojibiose, nigerose, maltose, isomaltose, sucrose, maltitol, and sorbitol). Quantum chemical calculations revealed that the OH-3 and OH-6 groups bind to the olefin double bonds of the diene through OH...pi and CH...O types of hydrogen bonds, respectively, and the stabilization energy of the resulting complex is 5-6 kcal mol(-1). These results strongly support the above NMR results. Finally, the activation energies were calculated for the hydrogen abstraction reactions from the activated methylene group of heptadiene. In particular, when the reaction was initiated by a methyl radical, the activation energy was only 10 kcal mol(-1) for the free heptadiene, but on complexation with trehalose it drastically increased to ca. 40 kcal mol(-1). This indicates that trehalose has a significant depression effect on the oxidation of the diene compounds. These results strongly

  9. Mechanical characterization of filler sandcretes with rice husk ash additions. Study applied to Senegal

    SciTech Connect

    Cisse, I.K.; Laquerbe, M.

    2000-01-01

    To capitalize on the local materials of Senegal (agricultural and industrial wastes, residual fines from crushing process, sands from dunes, etc.), rise husk ash and residues of industrial and agricultural wastes have been used as additions in sandcretes. The mechanical resistance of sandcrete blocks obtained when unground ash (and notably the ground ash) is added reveals that there is an increase in performance over the classic mortar blocks. In addition, the use of unground rice husk ash enables production of a lightweight sandcrete with insulating properties, at a reduced cost. The ash pozzolanic reactivity explains the high strengths obtained.

  10. Computational study of the rate constants and free energies of intramolecular radical addition to substituted anilines

    PubMed Central

    Seddiqzai, Meriam; Dahmen, Tobias; Sure, Rebecca

    2013-01-01

    Summary The intramolecular radical addition to aniline derivatives was investigated by DFT calculations. The computational methods were benchmarked by comparing the calculated values of the rate constant for the 5-exo cyclization of the hexenyl radical with the experimental values. The dispersion-corrected PW6B95-D3 functional provided very good results with deviations for the free activation barrier compared to the experimental values of only about 0.5 kcal mol−1 and was therefore employed in further calculations. Corrections for intramolecular London dispersion and solvation effects in the quantum chemical treatment are essential to obtain consistent and accurate theoretical data. For the investigated radical addition reaction it turned out that the polarity of the molecules is important and that a combination of electrophilic radicals with preferably nucleophilic arenes results in the highest rate constants. This is opposite to the Minisci reaction where the radical acts as nucleophile and the arene as electrophile. The substitution at the N-atom of the aniline is crucial. Methyl substitution leads to slower addition than phenyl substitution. Carbamates as substituents are suitable only when the radical center is not too electrophilic. No correlations between free reaction barriers and energies (ΔG ‡ and ΔG R) are found. Addition reactions leading to indanes or dihydrobenzofurans are too slow to be useful synthetically. PMID:24062821

  11. Studies on the Food Additive Propyl Gallate: Synthesis, Structural Characterization, and Evaluation of the Antioxidant Activity

    ERIC Educational Resources Information Center

    Garrido, Jorge; Garrido, E. Manuela; Borges, Fernanda

    2012-01-01

    Antioxidants are additives largely used in industry for delaying, retarding, or preventing the development of oxidative deterioration. Propyl gallate (E310) is a phenolic antioxidant extensively used in the food, cosmetics, and pharmaceutical industries. A series of lab experiments have been developed to teach students about the importance and…

  12. Generation of a large volume of clinically relevant nanometre-sized ultra-high-molecular-weight polyethylene wear particles for cell culture studies.

    PubMed

    Liu, Aiqin; Ingham, Eileen; Fisher, John; Tipper, Joanne L

    2014-04-01

    It has recently been shown that the wear of ultra-high-molecular-weight polyethylene in hip and knee prostheses leads to the generation of nanometre-sized particles, in addition to micron-sized particles. The biological activity of nanometre-sized ultra-high-molecular-weight polyethylene wear particles has not, however, previously been studied due to difficulties in generating sufficient volumes of nanometre-sized ultra-high-molecular-weight polyethylene wear particles suitable for cell culture studies. In this study, wear simulation methods were investigated to generate a large volume of endotoxin-free clinically relevant nanometre-sized ultra-high-molecular-weight polyethylene wear particles. Both single-station and six-station multidirectional pin-on-plate wear simulators were used to generate ultra-high-molecular-weight polyethylene wear particles under sterile and non-sterile conditions. Microbial contamination and endotoxin levels in the lubricants were determined. The results indicated that microbial contamination was absent and endotoxin levels were low and within acceptable limits for the pharmaceutical industry, when a six-station pin-on-plate wear simulator was used to generate ultra-high-molecular-weight polyethylene wear particles in a non-sterile environment. Different pore-sized polycarbonate filters were investigated to isolate nanometre-sized ultra-high-molecular-weight polyethylene wear particles from the wear test lubricants. The use of the filter sequence of 10, 1, 0.1, 0.1 and 0.015 µm pore sizes allowed successful isolation of ultra-high-molecular-weight polyethylene wear particles with a size range of < 100 nm, which was suitable for cell culture studies.

  13. Bioaccessibility, bioavailability and toxicity of commercially relevant iron- and chromium-based particles: in vitro studies with an inhalation perspective

    PubMed Central

    2010-01-01

    Background Production of ferrochromium alloys (FeCr), master alloys for stainless steel manufacture, involves casting and crushing processes where particles inevitably become airborne and potentially inhaled. The aim of this study was to assess potential health hazards induced by inhalation of different well-characterized iron- and chromium-based particles, i.e. ferrochromium (FeCr), ferrosiliconchromium (FeSiCr), stainless steel (316L), iron (Fe), chromium (Cr), and chromium(III)oxide (Cr2O3), in different size fractions using in vitro methods. This was done by assessing the extent and speciation of released metals in synthetic biological medium and by analyzing particle reactivity and toxicity towards cultured human lung cells (A549). Results The amount of released metals normalized to the particle surface area increased with decreasing particle size for all alloy particles, whereas the opposite situation was valid for particles of the pure metals. These effects were evident in artificial lysosomal fluid (ALF) of pH 4.5 containing complexing agents, but not in neutral or weakly alkaline biological media. Chromium, iron and nickel were released to very low extent from all alloy particles, and from particles of Cr due to the presence of a Cr(III)-rich protective surface oxide. Released elements were neither proportional to the bulk nor to the surface composition after the investigated 168 hours of exposure. Due to a surface oxide with less protective properties, significantly more iron was released from pure iron particles compared with the alloys. Cr was predominantly released as Cr(III) from all particles investigated and was strongly complexed by organic species of ALF. Cr2O3 particles showed hemolytic activity, but none of the alloy particles did. Fine-sized particles of stainless steel caused however DNA damage, measured with the comet assay after 4 h exposure. None of the particles revealed any significant cytotoxicity in terms of cell death after 24 h

  14. In situ and ex situ studies of materials with relevance to electrochemical energy storage and energy generation

    NASA Astrophysics Data System (ADS)

    Luo, Yu

    Surface analytical techniques have been employed for the preparation and characterization of modified surfaces of relevance to electrochemical energy storage and generation in ultrahigh vacuum environments. Complementary in situ spectroscopic studies were also performed using Raman microscopy for monitoring static and dynamic aspects of Li intercalation and deintercalation into transition metal oxides and graphitic materials. The most important conclusions emerging from this investigation can be summarized as follows: (i) Ruthenium-modified Pt(100) surfaces of very high purity and controlled stoichiometry were prepared in ultrahigh vacuum (UHV) by irradiating Ru3(CO)12 films condensed on cold Pt substrates at 150 K with X-rays, and subsequent annealing at ca. 620 K. Exposure of non-annealed Ru(thetaRu ≥0.22)/Pt(100) to large exposures of CO at ca. 200 K, yielded smaller theta CO, and temperature programmed desorption peaks ca. 50 K lower than those observed for bare Pt(100). (ii) Raman spectra of isolated single particles of technical grade LiMn2O4 embedded in Au foils were recorded in situ in 1M LiPF6 in EC/DMC solutions in real time during a voltammetric scan using a Raman microscope. Similar experiments involving single KS-44 carbon particles (8--50 mum in diameter) embedded into thermally annealed Ni foils in 1M LiClO4, ethylene carbonate (EC) diethyl carbonate (DEC) solutions allowed the average concentration of Li+ within the volume of the particle probed by the laser beam following application of a potential step to be monitored spectroscopically in real time. Analysis of these transient data yielded deintercalation time constants for Li+ for dilute stage 1 phase consistent with reported values of Li+ diffusion coefficients within graphitic materials. A new Raman band ascribed to bounding graphite layers was found upon continuous cycling of single KS-44 particles deep into the Li+-intercalation region. This feature was attributed to chemical modifications

  15. Environmentally relevant microorganisms.

    PubMed

    Watanabe, K; Baker, P W

    2000-01-01

    The development of molecular microbial ecology in the 1990s has allowed scientists to realize that microbial populations in the natural environment are much more diverse than microorganisms so far isolated in the laboratory. This finding has exerted a significant impact on environmental biotechnology, since knowledge in this field has been largely dependent on studies with pollutant-degrading bacteria isolated by conventional culture methods. Researchers have thus started to use molecular ecological methods to analyze microbial populations relevant to pollutant degradation in the environment (called environmentally relevant microorganisms, ERMs), although further effort is needed to gain practical benefits from these studies. This review highlights the utility and limitations of molecular ecological methods for understanding and advancing environmental biotechnology processes. The importance of the combined use of molecular ecological and physiological methods for identifying ERMs is stressed.

  16. A Military Relevant Model of Closed Concussive Head Injury: Longitudinal Studies Characterizing and Validating Single and Repetitive mTBI

    DTIC Science & Technology

    2015-10-01

    may serve as indicators of mild traumatic brain injury (mTBI). This injury model represents a mild clinically relevant injury. Briefly, PCI injury...consciousness after concussion. These findings suggest that brain cathepsin B has a role in multiple TBI models and is linked to neurological deficits...Mountney A, Deng-Bryant Y, Schmid K, Shear D, Tortella F (2014) The WRAIR projectile concussive impact model of mild traumatic brain injury: re- design

  17. Study of Monotonic Properties' Relevance for Estimation of Cyclic Yield Stress and Ramberg-Osgood Parameters of Steels

    NASA Astrophysics Data System (ADS)

    Marohnić, Tea; Basan, Robert

    2016-11-01

    Most of existing methods for estimation of cyclic stress-strain parameters have been developed for steels in general with no regard to the peculiarities of individual steel subgroups. Also, proposed models were commonly developed and evaluated without systematically determining if, and to what extent, individual monotonic properties contribute to their accuracy. In this work, a thorough statistical analysis of experimental datasets of 116 different steels obtained from literature was performed in order to determine which monotonic properties might be relevant for the estimation of cyclic yield stress and cyclic Ramberg-Osgood parameters of unalloyed, low-alloy and high-alloy steels. Only certain monotonic properties used in existing methods were found to be suitable for estimation purposes, while for a number of monotonic properties used in those references no such conclusion can be given. Furthermore, obtained results indicate that steels should not be treated as a single group since different sets of monotonic properties proved to be relevant for unalloyed, low- and high-alloy steel subgroups. Provided list of specific monotonic properties relevant for estimation of individual cyclic parameters of particular steel subgroups can be used for improving the accuracy of existing or development of new estimation methods.

  18. A laboratory study of the perceived benefit of additional noise attenuation by houses

    NASA Technical Reports Server (NTRS)

    Flindell, I. H.

    1983-01-01

    Two Experiments were conducted to investigate the perceived benefit of additional house attenuation against aircraft flyover noise. First, subjects made annoyance judgments in a simulated living room while an operative window with real and dummy storm windows was manipulated in full view of those subjects. Second, subjects made annoyance judgments in an anechoic audiometric test chamber of frequency shaped noise signals having spectra closely matched to those of the aircraft flyover noises reproduced in the first experiment. These stimuli represented the aircraft flyover noises in levels and spectra but without the situational and visual cues present in the simulated living room. Perceptual constancy theory implies that annoyance tends to remain constant despite reductions in noise level caused by additional attenuation of which the subjects are fully aware. This theory was supported when account was taken for a reported annoyance overestimation for certain spectra and for a simulated condition cue overreaction.

  19. A Search for Additional Planets in the Exoplanetary Systems Studied by the NASA EPOXI Mission

    NASA Astrophysics Data System (ADS)

    Ballard, Sarah; Christiansen, J. L.; Charbonneau, D.; Holman, M. J.; Deming, D.; Wellnitz, D. D.; A'Hearn, M. F.; EPOXI Team

    2010-01-01

    The EPOCh (Extrasolar Planet Observation and Characterization) component of the NASA EPOXI mission used the HRI camera aboard the Deep Impact spacecraft to observe transiting exoplanet systems from January through August 2008. The majority of these targets were each observed nearly continuously for several weeks at a time. We searched these high-precision time series for additional planets in these systems, which could be revealed either directly through their photometric transits, or indirectly through the variations these second planets induce on the times of transit of the previously known planet. We present upper limits on putative additional planets in six of the systems observed by EPOXI: HAT-P-4, TrES-3, GJ 436, TrES-2, WASP-3, and HAT-P-7.

  20. Thiopeptin, a New Feed-Additive Antibiotic: Biological Studies and Field Trials

    PubMed Central

    Mine, K.; Miyairi, N.; Takano, N.; Mori, S.; Watanabe, N.

    1972-01-01

    Thiopeptin is a new antibiotic, produced by Streptomyces tateyamensis and developed solely for animal use as a feed additive. The antibiotic content in animal tissue and feed was assayed in terms of the antimicrobial activity against Mycoplasma laidlawii A. This antibiotic was found to be relatively nontoxic in rats and mice. In chickens, this antibiotic is excreted into feces within 48 hr of administration and is not absorbed in tissue. It is well tolerated in both broilers and swine and is highly stable in animal feed. Thiopeptin-supplemented feed contributes to the improvement of weight gain, feed efficiency in chickens and swine, and the egg performance in layers. Thus, thiopeptin, when used as a feed additive, is quite suitable for supplementing animal nutrition. PMID:4680812

  1. Structural changes in gluten protein structure after addition of emulsifier. A Raman spectroscopy study

    NASA Astrophysics Data System (ADS)

    Ferrer, Evelina G.; Gómez, Analía V.; Añón, María C.; Puppo, María C.

    2011-06-01

    Food protein product, gluten protein, was chemically modified by varying levels of sodium stearoyl lactylate (SSL); and the extent of modifications (secondary and tertiary structures) of this protein was analyzed by using Raman spectroscopy. Analysis of the Amide I band showed an increase in its intensity mainly after the addition of the 0.25% of SSL to wheat flour to produced modified gluten protein, pointing the formation of a more ordered structure. Side chain vibrations also confirmed the observed changes.

  2. A Delphi Study of Additive Manufacturing Applicability for United States Air Force Civil Engineer Contingency Operations

    DTIC Science & Technology

    2015-03-26

    This simple process is the basis for most consumer-grade desktop AM machines, commonly known as 3D printers (Pham & Gault, 1998:1270). Material...as a single purchase to decrease initial capital costs. Once the 3D printers are purchased and delivered, the selected bases can begin training...for several Questions if you would liKe to explain or elaborate on your answers. Additional information •out 3D printers and UTCs is provided as an

  3. Magnetic Force Microscopy Study of Zr2Co11 -Based Nanocrystalline Materials: Effect of Mo Addition

    DOE PAGES

    Yue, Lanping; Jin, Yunlong; Zhang, Wenyong; ...

    2015-01-01

    Tmore » he addition of Molybdenum was used to modify the nanostructure and enhance coercivity of rare-earth-free Zr2Co11-based nanocrystalline permanent magnets. he effect of Mo addition on magnetic domain structures of melt spun nanocrystalline Zr16Co84-xMox(x=0, 0.5, 1, 1.5, and 2.0) ribbons has been investigated. It was found that magnetic properties and local domain structures are strongly influenced by Mo doping. he coercivity of the samples increases with the increase in Mo content (x≤1.5). he maximum energy product(BH)maxincreases with increasingxfrom 0.5 MGOe forx=0to a maximum value of 4.2 MGOe forx=1.5. he smallest domain size with a relatively short magnetic correlation length of 128 nm and largest root-mean-square phase shiftΦrmsvalue of 0.66° are observed for thex=1.5. he optimal Mo addition promotes magnetic domain structure refinement and thus leads to a significant increase in coercivity and energy product in this sample.« less

  4. Load bearing and stiffness tailored NiTi implants produced by additive manufacturing: a simulation study

    NASA Astrophysics Data System (ADS)

    Rahmanian, Rasool; Shayesteh Moghaddam, Narges; Haberland, Christoph; Dean, David; Miller, Michael; Elahinia, Mohammad

    2014-03-01

    Common metals for stable long-term implants (e.g. stainless steel, Titanium and Titanium alloys) are much stiffer than spongy cancellous and even stiffer than cortical bone. When bone and implant are loaded this stiffness mismatch results in stress shielding and as a consequence, degradation of surrounding bony structure can lead to disassociation of the implant. Due to its lower stiffness and high reversible deformability, which is associated with the superelastic behavior, NiTi is an attractive biomaterial for load bearing implants. However, the stiffness of austenitic Nitinol is closer to that of bone but still too high. Additive manufacturing provides, in addition to the fabrication of patient specific implants, the ability to solve the stiffness mismatch by adding engineered porosity to the implant. This in turn allows for the design of different stiffness profiles in one implant tailored to the physiological load conditions. This work covers a fundamental approach to bring this vision to reality. At first modeling of the mechanical behavior of different scaffold designs are presented as a proof of concept of stiffness tailoring. Based on these results different Nitinol scaffolds can be produced by additive manufacturing.

  5. Study of the structure of steel 12Kh12M1BFP modified with additions of fullerenes and carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Glebov, V. A.; Bakulina, A. S.; Efremov, I. V.; Shchetinin, I. V.; Yagodkin, Yu. D.; Glezer, A. M.; Rashkovskii, A. Yu.; Vainshtein, D. L.

    2010-12-01

    X-ray structural analysis, scanning electron microscopy, x-ray photoelectron spectroscopy, atomic force microscopy are used to study the structure of compacted specimens of steel 12Kh12M1BFP, modified with additions of fullerenes and carbon nanotubes. The effect of additions on the microhardness of compacted specimens is established.

  6. OH-radical specific addition to the antioxidant glutathione S-atom at the air-water interface - Relevance to the redox balance of the lung epithelial lining fluid and the causality of adverse health effects induced by air pollution

    NASA Astrophysics Data System (ADS)

    Colussi, A. J.; Enami, S.; Hoffmann, M. R.

    2015-12-01

    Inhalation of oxidant pollutants upsets the redox balance (RB) of the lung epithelial lining fluid (ELF) by triggering the formation of reactive OH-radicals therein. RB is deemed to be controlled by the equilibrium between the most abundant ELF protective antioxidant glutathione (GSH) and its putative disulfide GSSG oxidation product. The actual species produced from the oxidation of GSH initiated by ·OH in ELF interfacial layers exposed to air, i.e., under realistic ELF conditions, however, were never identified. Here we report the online electrospray mass spectrometric detection of sulfenate (GSO-), sulfinate (GSO2-) and sulfonate (GSO3-) on the surface of aqueous GSH solutions collided with ·OH(g). We show that these products arise from ·OH specific additions to S-atoms, rather than via H-abstraction from GS-H. The remarkable specificity of ·OH in interfacial water vis-a-vis its lack of selectivity in bulk water implicates an unprecedented steering process during ·OH-GSH encounters at water interfaces. A non-specific systemic immune response to inhaled oxidants should be expected if they were initially converted into a common ·OH intermediate on the ELF (e.g., via fast Fenton chemistry) and oxidative stress signaled by the [GSH]/[GSOH] ratio.

  7. Laboratory studies of humidity-driven phase transitions of perchlorate/chloride mixtures: Relevance to aqueous phases on Mars

    NASA Astrophysics Data System (ADS)

    Gough, R. V.; Tolbert, M. A.

    2012-12-01

    Perchlorate salts, known to exist on Mars, can readily absorb water vapor and deliquesce into aqueous solution. We have previously studied pure perchlorate and found that the deliquescence relative humidity (DRH) is <60% regardless of cation, hydration state or temperature (223 to 273 K). We have also shown that efflorescence (recrystallization) of perchlorate solutions is kinetically hindered, allowing supersaturation to occur at RH values below the DRH. In addition to perchlorate, Phoenix instruments found chloride, sulfate, carbonate, magnesium, sodium, potassium and calcium in the Martian regolith. The vertical and spatial distributions of these ions are unknown, but all were present in a single 1 g sample. It is therefore likely that these ions coexist with perchlorate. Many salts likely present in the regolith are less deliquescent than perchlorates, and it is important to understand how these additional species will affect perchlorate deliquescence. Here we study deliquescence (solid to aqueous transition) and efflorescence (aqueous to solid transition) of 3 perchlorate/chloride systems: KClO4/KCl at 253 K and NaClO4/NaCl and Mg(ClO4)2/MgCl2 at 243 and 253 K. A Raman microscope and environmental cell were used to monitor phase transitions of internally mixed perchlorate/chloride particles. The eutonic RH, where an aqueous phase first forms, is 30% RH for Mg(ClO4)2/MgCl2, 38% RH for NaClO4/NaCl and 82% RH for KClO4/KCl mixtures regardless of initial composition. We observed complete deliquescence of all salt mixtures at RH values below the DRH of the least deliquescent pure salt. When humidity is lowered, efflorescence of all solutions occurred below the DRH suggesting supersaturated solutions can exist. The low eutonic RH values of the sodium and magnesium perchlorate/chloride mixtures are significant for Mars, as these humidities can be reached at the Martian surface. It is likely that some salts in the regolith may exist as stable or metastable solutions

  8. Strategic Petroleum Reserve (SPR) additional geologic site characterization studies, Bryan Mound Salt Dome, Texas

    SciTech Connect

    Neal, J.T.; Magorian, T.R.; Ahmad, S.

    1994-11-01

    This report revises the original report that was published in 1980. Some of the topics covered in the earlier report were provisional and it is now practicable to reexamine them using new or revised geotechnical data and that obtained from SPR cavern operations, which involves 16 new caverns. Revised structure maps and sections show interpretative differences as compared with the 1980 report and more definition in the dome shape and caprock structural contours, especially a major southeast-northwest trending anomalous zone. The original interpretation was of westward tilt of the dome, this revision shows a tilt to the southeast, consistent with other gravity and seismic data. This interpretation refines the evaluation of additional cavern space, by adding more salt buffer and allowing several more caverns. Additional storage space is constrained on this nearly full dome because of low-lying peripheral wetlands, but 60 MMBBL or more of additional volume could be gained in six or more new caverns. Subsidence values at Bryan Mound are among the lowest in the SPR system, averaging about 11 mm/yr (0.4 in/yr), but measurement and interpretation issues persist, as observed values are about the same as survey measurement accuracy. Periodic flooding is a continuing threat because of the coastal proximity and because peripheral portions of the site are at elevations less than 15 ft. This threat may increase slightly as future subsidence lowers the surface, but the amount is apt to be small. Caprock integrity may be affected by structural features, especially the faulting associated with anomalous zones. Injection wells have not been used extensively at Bryan Mound, but could be a practicable solution to future brine disposal needs. Environmental issues center on the areas of low elevation that are below 15 feet above mean sea level: the coastal proximity and lowland environment combined with the potential for flooding create conditions that require continuing surveillance.

  9. Analysis of Pipeline Steel Corrosion Data From NBS (NIST) Studies Conducted Between 1922-1940 and Relevance to Pipeline Management.

    PubMed

    Ricker, Richard E

    2010-01-01

    commercially available software packages for statistical analysis. The emphasis was on identifying trends in the data that could be later exploited in the development of an empirical model for predicting the range of expected corrosion behavior for any given set of soil chemistry and conditions. A large number of issues were identified with this corrosion dataset, but given the limited knowledge of corrosion and statistical analysis at the time the study was conducted, these shortcomings are not surprising and many of these were recognized by the investigators before the study was concluded. However, it is important to keep in mind that complete soil data is provided for less than half of the sites in this study. In agreement with the initial study, it was concluded that any differences in the corrosion behavior of the alloys could not be resolved due to the scatter in the results from the environmental factors and no significant difference could be determined between alloys. Linear regression and curve fitting of the corrosion damage measurements against the measured soil composition and properties found some weak trends. These trends improved with multiple regression, and empirical equations representing the performance of the samples in the tests were developed with uncertainty estimates. The uncertainties in these empirical models for the corrosion data were large, and extrapolation beyond the parameter space or exposure times of these experiments will create additional uncertainties. It is concluded that equations for the estimation of corrosion damage distributions and rates can be developed from these data, but these models will always have relatively large uncertainties that will limit their utility. These uncertainties result from the scatter in the measurements due to annual, seasonal, and sample position dependent variations at the burial sites. The data indicate that more complete datasets with soil property measurements reflecting the properties of the soil and

  10. Levinson's Dream Theory and Its Relevance in an Academic Executive Mentoring Program: An Exploratory Study of Executive Mentors' Practice and Individuation

    ERIC Educational Resources Information Center

    Scherer, Douglas Martin

    2010-01-01

    The purpose of this study was to explore the relevance that executive mentors' Dream journeys had for their mentoring practices. Dream journeys are the visions of where young adults see themselves in the future, and how they integrate themselves into the adult world over time. It was anticipated that a better understanding of executive mentors'…

  11. A Review of Concepts from Policy Studies Relevant to the Analysis of EFA in Developing Countries. Create Pathways to Access. Research Monograph No. 11

    ERIC Educational Resources Information Center

    Lall, Marie

    2007-01-01

    This paper aims to give an introduction to the central concepts and the literature of Policy Studies in education. The first part of the paper addresses the questions of what policy is. How is it made and why is it relevant? It looks in particular at the role of the state and the Policy cycle framework which is an analytical tool that helps to…

  12. An Evaluation Study of the Young Empowered Sisters (YES!) Program: Promoting Cultural Assets among African American Adolescent Girls through a Culturally Relevant School-Based Intervention

    ERIC Educational Resources Information Center

    Thomas, Oseela; Davidson, William; McAdoo, Harriette

    2008-01-01

    The present study examines the effects of a culturally relevant school-based intervention in promoting cultural assets (i.e., ethnic identity, collectivist orientation, racism awareness, and liberatory youth activism) among a group of African American adolescent girls. The overall goal of the intervention was to promote cultural factors that can…

  13. Toxicity of CeO₂ nanoparticles on a freshwater experimental trophic chain: A study in environmentally relevant conditions through the use of mesocosms.

    PubMed

    Bour, Agathe; Mouchet, Florence; Cadarsi, Stéphanie; Silvestre, Jérôme; Verneuil, Laurent; Baqué, David; Chauvet, Eric; Bonzom, Jean-Marc; Pagnout, Christophe; Clivot, Hugues; Fourquaux, Isabelle; Tella, Marie; Auffan, Mélanie; Gauthier, Laury; Pinelli, Eric

    2016-01-01

    The toxicity of CeO2 NPs on an experimental freshwater ecosystem was studied in mesocosm, with a focus being placed on the higher trophic level, i.e. the carnivorous amphibian species Pleurodeles waltl. The system comprised species at three trophic levels: (i) bacteria, fungi and diatoms, (ii) Chironomus riparius larvae as primary consumers and (iii) Pleurodeles larvae as secondary consumers. NP contamination consisted of repeated additions of CeO2 NPs over 4 weeks, to obtain a final concentration of 1 mg/L. NPs were found to settle and accumulate in the sediment. No effects were observed on litter decomposition or associated fungal biomass. Changes in bacterial communities were observed from the third week of NP contamination. Morphological changes in CeO2 NPs were observed at the end of the experiment. No toxicity was recorded in chironomids, despite substantial NP accumulation (265.8 ± 14.1 mg Ce/kg). Mortality (35.3 ± 6.8%) and a mean Ce concentration of 13.5 ± 3.9 mg/kg were reported for Pleurodeles. Parallel experiments were performed on Pleurodeles to determine toxicity pathways: no toxicity was observed by direct or dietary exposures, although Ce concentrations almost reached 100 mg/kg. In view of these results, various toxicity mechanisms are proposed and discussed. The toxicity observed on Pleurodeles in mesocosm may be indirect, due to microorganism's interaction with CeO2 NPs, or NP dissolution could have occurred in mesocosm due to the structural complexity of the biological environment, resulting in toxicity to Pleurodeles. This study strongly supports the importance of ecotoxicological assessment of NPs under environmentally relevant conditions, using complex biological systems.

  14. A Review of Approaches to the Study of Turbulence Modification by Means of Non-Newtonian Additives

    DTIC Science & Technology

    1987-12-10

    interesting class of polymers for drag reduction studies. These polymers ( xanthomonas campestris , guar gum) were found to show long term stability...and their superiority to "typical" drag reducing polymers like polyethylene oxide, was evident. His degradation studies showed that the xanthomonas ... campestris is a better and more durable additive than guar gum. One of the most important biological additives is the DNA. It is actually a random

  15. A comparative quantitative proteomic study identifies new proteins relevant for sulfur oxidation in the purple sulfur bacterium Allochromatium vinosum.

    PubMed

    Weissgerber, Thomas; Sylvester, Marc; Kröninger, Lena; Dahl, Christiane

    2014-04-01

    In the present study, we compared the proteome response of Allochromatium vinosum when growing photoautotrophically in the presence of sulfide, thiosulfate, and elemental sulfur with the proteome response when the organism was growing photoheterotrophically on malate. Applying tandem mass tag analysis as well as two-dimensional (2D) PAGE, we detected 1,955 of the 3,302 predicted proteins by identification of at least two peptides (59.2%) and quantified 1,848 of the identified proteins. Altered relative protein amounts (≥1.5-fold) were observed for 385 proteins, corresponding to 20.8% of the quantified A. vinosum proteome. A significant number of the proteins exhibiting strongly enhanced relative protein levels in the presence of reduced sulfur compounds are well documented essential players during oxidative sulfur metabolism, e.g., the dissimilatory sulfite reductase DsrAB. Changes in protein levels generally matched those observed for the respective relative mRNA levels in a previous study and allowed identification of new genes/proteins participating in oxidative sulfur metabolism. One gene cluster (hyd; Alvin_2036-Alvin_2040) and one hypothetical protein (Alvin_2107) exhibiting strong responses on both the transcriptome and proteome levels were chosen for gene inactivation and phenotypic analyses of the respective mutant strains, which verified the importance of the so-called Isp hydrogenase supercomplex for efficient oxidation of sulfide and a crucial role of Alvin_2107 for the oxidation of sulfur stored in sulfur globules to sulfite. In addition, we analyzed the sulfur globule proteome and identified a new sulfur globule protein (SgpD; Alvin_2515).

  16. A pilot-scale study of selective desulfurization via urea addition in iron ore sintering

    NASA Astrophysics Data System (ADS)

    Long, Hong-ming; Wu, Xue-jian; Chun, Tie-jun; Di, Zhan-xia; Wang, Ping; Meng, Qing-min

    2016-11-01

    The iron ore sintering process is the main source of SO2 emissions in the iron and steel industry. In our previous research, we proposed a novel technology for reducing SO2 emissions in the flue gas in the iron ore sintering process by adding urea at a given distance from the sintering grate bar. In this paper, a pilot-scale experiment was carried out in a commercial sintering plant. The results showed that, compared to the SO2 concentration in flue gas without urea addition, the SO2 concentration decreased substantially from 694.2 to 108.0 mg/m3 when 0.10wt% urea was added. NH3 decomposed by urea reacted with SO2 to produce (NH4)2SO4, decreasing the SO2 concentration in the flue gas.

  17. THERMODYNAMIC STUDY OF THE NICKEL ADDITION IN ZINC HOT-DIP GALVANIZING BATHS

    SciTech Connect

    Pistofidis, N.; Vourlias, G.

    2010-01-21

    A usual practice during zinc hot-dip galvanizing is the addition of nickel in the liquid zinc which is used to inhibit the Sandelin effect. Its action is due to the fact that the zeta(zeta) phase of the Fe-Zn system is replaced by the TAU(tau) phase of the Fe-Zn-Ni system. In the present work an attempt is made to explain the formation of the TAU phase with thermodynamics. For this reason the Gibbs free energy changes for TAU and zeta phases were calculated. The excess free energy for the system was calculated with the Redlich-Kister polyonyme. From this calculation it was deduced that the Gibbs energy change for the tau phase is negative. As a result its formation is spontaneous.

  18. Additive Manufacturing of a Microbial Fuel Cell—A detailed study

    PubMed Central

    Calignano, Flaviana; Tommasi, Tonia; Manfredi, Diego; Chiolerio, Alessandro

    2015-01-01

    In contemporary society we observe an everlasting permeation of electron devices, smartphones, portable computing tools. The tiniest living organisms on Earth could become the key to address this challenge: energy generation by bacterial processes from renewable stocks/waste through devices such as microbial fuel cells (MFCs). However, the application of this solution was limited by a moderately low efficiency. We explored the limits, if any, of additive manufacturing (AM) technology to fabricate a fully AM-based powering device, exploiting low density, open porosities able to host the microbes, systems easy to fuel continuously and to run safely. We obtained an optimal energy recovery close to 3 kWh m−3 per day that can power sensors and low-power appliances, allowing data processing and transmission from remote/harsh environments. PMID:26611142

  19. Preliminary study of neutron absorption by concrete with boron carbide addition

    SciTech Connect

    Abdullah, Yusof Yusof, Mohd Reusmaazran; Zali, Nurazila Mat; Ahmad, Megat Harun Al Rashid Megat; Yazid, Hafizal; Ariffin, Fatin Nabilah Tajul; Ahmad, Sahrim; Hamid, Roszilah; Mohamed, Abdul Aziz

    2014-02-12

    Concrete has become a conventional material in construction of nuclear reactor due to its properties like safety and low cost. Boron carbide was added as additives in the concrete construction as it has a good neutron absorption property. The sample preparation for concrete was produced with different weight percent of boron carbide powder content. The neutron absorption rate of these samples was determined by using a fast neutron source of Americium-241/Be (Am-Be 241) and detection with a portable backscattering neutron detector. Concrete with 20 wt % of boron carbide shows the lowest count of neutron transmitted and this indicates the most neutrons have been absorbed by the concrete. Higher boron carbide content may affect the concrete strength and other properties.

  20. Additive Manufacturing of a Microbial Fuel Cell--A detailed study.

    PubMed

    Calignano, Flaviana; Tommasi, Tonia; Manfredi, Diego; Chiolerio, Alessandro

    2015-11-27

    In contemporary society we observe an everlasting permeation of electron devices, smartphones, portable computing tools. The tiniest living organisms on Earth could become the key to address this challenge: energy generation by bacterial processes from renewable stocks/waste through devices such as microbial fuel cells (MFCs). However, the application of this solution was limited by a moderately low efficiency. We explored the limits, if any, of additive manufacturing (AM) technology to fabricate a fully AM-based powering device, exploiting low density, open porosities able to host the microbes, systems easy to fuel continuously and to run safely. We obtained an optimal energy recovery close to 3 kWh m(-3) per day that can power sensors and low-power appliances, allowing data processing and transmission from remote/harsh environments.

  1. Additive Manufacturing of a Microbial Fuel Cell—A detailed study

    NASA Astrophysics Data System (ADS)

    Calignano, Flaviana; Tommasi, Tonia; Manfredi, Diego; Chiolerio, Alessandro

    2015-11-01

    In contemporary society we observe an everlasting permeation of electron devices, smartphones, portable computing tools. The tiniest living organisms on Earth could become the key to address this challenge: energy generation by bacterial processes from renewable stocks/waste through devices such as microbial fuel cells (MFCs). However, the application of this solution was limited by a moderately low efficiency. We explored the limits, if any, of additive manufacturing (AM) technology to fabricate a fully AM-based powering device, exploiting low density, open porosities able to host the microbes, systems easy to fuel continuously and to run safely. We obtained an optimal energy recovery close to 3 kWh m-3 per day that can power sensors and low-power appliances, allowing data processing and transmission from remote/harsh environments.

  2. Preliminary study of neutron absorption by concrete with boron carbide addition

    NASA Astrophysics Data System (ADS)

    Abdullah, Yusof; Ariffin, Fatin Nabilah Tajul; Hamid, Roszilah; Yusof, Mohd Reusmaazran; Zali, Nurazila Mat; Ahmad, Megat Harun Al Rashid Megat; Yazid, Hafizal; Ahmad, Sahrim; Mohamed, Abdul Aziz

    2014-02-01

    Concrete has become a conventional material in construction of nuclear reactor due to its properties like safety and low cost. Boron carbide was added as additives in the concrete construction as it has a good neutron absorption property. The sample preparation for concrete was produced with different weight percent of boron carbide powder content. The neutron absorption rate of these samples was determined by using a fast neutron source of Americium-241/Be (Am-Be 241) and detection with a portable backscattering neutron detector. Concrete with 20 wt % of boron carbide shows the lowest count of neutron transmitted and this indicates the most neutrons have been absorbed by the concrete. Higher boron carbide content may affect the concrete strength and other properties.

  3. Theoretical molecular descriptors relevant to the uptake of persistent organic pollutants from soil by zucchini. A QSAR study.

    PubMed

    Bordás, Barna; Bélai, Iván; Koomíves, Tamás

    2011-04-13

    The uptake of persistent organic pollutants (POPs) from soil by plants allows the development of phytoremediation protocols to rehabilitate contaminated areas. The use of diverse theoretical descriptors has been reported in the literature for developing quantitative structure-activity relationship (QSAR) models for predicting the bioconcentration factors (BCFs) of POPs in different plants. In this paper an evaluation is given on the molecular properties of POPs in terms of theoretical molecular descriptors that are relevant to the uptake and accumulation of these persistent pollutants from soil by two zucchini varieties. Statistically significant and predictive linear regression models have been developed for the BCF values of 20 polychlorinated dibenzo-p-dioxins/dibenzofurans and 14 polyhalogenated biphenyls in two zucchini varieties based on retrospective data. The relevant parameters have been selected from a set of 1660 DRAGON, 150 VolSurf, and 11 quantum chemical descriptors. The two most significant regression models, containing VolSurf, DRAGON GETAWAY, and quantum chemical descriptors, displayed the following statistical parameters: (eq 3) n = 27, R(2) = 0.940, q(2) = 0.922, SE = 0.155, F = 392.1; (eq 4) n = 27, R(2) = 0.921, q(2) = 0.898, SE = 0.161, F = 140.4. Predictive capabilities of the equations have been validated by using external validation sets. The QSAR models proposed might contribute to the development of viable soil remediation strategies.

  4. A comparative study of surface EMG classification by fuzzy relevance vector machine and fuzzy support vector machine.

    PubMed

    Xie, Hong-Bo; Huang, Hu; Wu, Jianhua; Liu, Lei

    2015-02-01

    We present a multiclass fuzzy relevance vector machine (FRVM) learning mechanism and evaluate its performance to classify multiple hand motions using surface electromyographic (sEMG) signals. The relevance vector machine (RVM) is a sparse Bayesian kernel method which avoids some limitations of the support vector machine (SVM). However, RVM still suffers the difficulty of possible unclassifiable regions in multiclass problems. We propose two fuzzy membership function-based FRVM algorithms to solve such problems, based on experiments conducted on seven healthy subjects and two amputees with six hand motions. Two feature sets, namely, AR model coefficients and room mean square value (AR-RMS), and wavelet transform (WT) features, are extracted from the recorded sEMG signals. Fuzzy support vector machine (FSVM) analysis was also conducted for wide comparison in terms of accuracy, sparsity, training and testing time, as well as the effect of training sample sizes. FRVM yielded comparable classification accuracy with dramatically fewer support vectors in comparison with FSVM. Furthermore, the processing delay of FRVM was much less than that of FSVM, whilst training time of FSVM much faster than FRVM. The results indicate that FRVM classifier trained using sufficient samples can achieve comparable generalization capability as FSVM with significant sparsity in multi-channel sEMG classification, which is more suitable for sEMG-based real-time control applications.

  5. Professional Competence Development of the Social Work Specialists in the Period of Study in the System of Additional Education

    ERIC Educational Resources Information Center

    Davletkaliev, Denis Kuanyshevich; Zueva, Natalia Konstantinovna; Lebedeva, Natalya Vasilevna; Mkrtumova, Irina Vladimirovna; Timofeeva, Olga

    2015-01-01

    The goal of this work is the study of psychological-pedagogical approaches to the understanding of the idea of professional competence of social work specialists as well as the role of study in the system of additional educations in professional-personal development of the listeners. In the process of study of this problem we define main…

  6. Spectroscopic Evidence for Covalent Binding of Sulfadiazine to Natural Soils via 1,4-nucleophilic addition (Michael Type Addition) studied by Spin Labeling ESR

    NASA Astrophysics Data System (ADS)

    Aleksandrova, Olga

    2015-04-01

    Among different classes of veterinary pharmaceuticals, Sulfadiazine (SDZ) is widely used in animal husbandry. Its residues were detected in different environmental compartments. However, soil is a hot spot for SDZ as it receives a large portion of excreted compounds through the application of manure during soil fertilization. Ample studies on the fate of SDZ in soils showed that a large portion forms nonextractable residues (NER) along with transformation products and a low mineralization (Mueller et al., 2013). A common observation was an initially fast formation of NER up to 10% of the applied amount promptly after the application of SDZ to soil, and this portion increased up to 50% within a few days (Mueller et al., 2013; Nowak et al., 2011). A common finding for SDZ, as for other sulfonamides, was biphasic kinetics of the formation of NER, which was attributed to the occurrence of two reaction processes: a rapid, often reversible process and a slower, irreversible process (Weber et al., 1996). A single-phase reaction process was also established under anaerobic treatment (Gulkowska et al., 2014). A major focus of this work is to elucidate a reaction mechanism of covalent binding of SDZ to soil that is currently required to estimate a risk of NER formed by SDZ in soils for human health. Taking into account a key role of the amine functional groups of SDZ on its reactivity in soil, nitroxide radicals with the sewed aromatic or aliphatic amines labeled soil samples and then, were investigated by means of ESR spectroscopy. 2,5,5-Trimethyl-2-(3-aminophenyl)pyrrolidin-1-yloxy and 4-amino-2,2,6,6-Tetramethylpiperidin-1-oxyl modeled decomposition products of SDZ with the aromatic and aliphatic amines, respectively. The application of the defined combination of both spin labels (SL) to different soils well simulated a change of a paramagnetic signal of soil organic radicals interacted with SDZ. After their application to soil, SL were found in soil sites characterized

  7. Using the Learning and Study Strategies Inventory Scores as Additional Predictors of Student Academic Performance.

    ERIC Educational Resources Information Center

    Rugsaken, Kris T.; Robertson, Jacqueline A.; Jones, James A.

    1998-01-01

    A study investigated the usefulness of the Learning and Study Strategies Inventory in predicting college students' academic performance, focusing on whether the scores enhance the accuracy of traditional predictors such as college entrance examinations and high school rank. Results indicate the scores produce a slight but not significant increase…

  8. Te Rita Papesch: Case Study of an Exemplary Learner of Maori as an Additional Language

    ERIC Educational Resources Information Center

    Ratima, Matiu Tai; Papesch, Te Rita

    2014-01-01

    This paper presents a case study of the life experiences of one exemplar adult second language Maori learner--Te Rita Papesch. Te Rita was one of 17 participants who were interviewed as a part of the first author's PhD study which sought to answer the question: what factors lead to the development of proficiency in te reo Maori amongst adult…

  9. Sensitization to Food Additives in Patients with Allergy: A Study Based on Skin Test and Open Oral Challenge.

    PubMed

    Moghtaderi, Mozhgan; Hejrati, Zinatosadat; Dehghani, Zahra; Dehghani, Faranak; Kolahi, Niloofar

    2016-06-01

    There has been a great increase in the consumption of various food additives in recent years. The purpose of this study was to identify the incidence of sensitization to food additives by using skin prick test in patients with allergy and to determine the concordance rate between positive skin tests and oral challenge in hypersensitivity to additives. This cross-sectional study included 125 (female 71, male 54) patients aged 2-76 years with allergy and 100 healthy individuals. Skin tests were performed in both patient and control groups with 25 fresh food additives. Among patients with allergy, 22.4% showed positive skin test at least to one of the applied materials. Skin test was negative to all tested food additives in control group. Oral food challenge was done in 28 patients with positive skin test, in whom 9 patients showed reaction to culprit (Concordance rate=32.1%). The present study suggested that about one-third of allergic patients with positive reaction to food additives showed positive oral challenge; it may be considered the potential utility of skin test to identify the role of food additives in patients with allergy.

  10. Exploratory studies of extended storage of apheresis platelets in a platelet additive solution (PAS).

    PubMed

    Slichter, Sherrill J; Corson, Jill; Jones, Mary Kay; Christoffel, Todd; Pellham, Esther; Bailey, S Lawrence; Bolgiano, Doug

    2014-01-09

    To evaluate the poststorage viability of apheresis platelets stored for up to 18 days in 80% platelet additive solution (PAS)/20% plasma, 117 healthy subjects donated platelets using the Haemonetics MCS+, COBE Spectra (Spectra), or Trima Accel (Trima) systems. Control platelets from the same subjects were compared with their stored test PAS platelets by radiolabeling their stored and control platelets with either (51)chromium or (111)indium. Trima platelets met Food and Drug Administration poststorage platelet viability criteria for only 7 days vs almost 13 days for Haemonetics platelets; ie, platelet recoveries after these storage times averaged 44 ± 3% vs 49 ± 3% and survivals were 5.4 ± 0.3 vs 4.6 ± 0.3 days, respectively. The differences in storage duration are likely related to both the collection system and the storage bag. The Spectra and Trima platelets were hyperconcentrated during collection, and PAS was added, whereas the Haemonetics platelets were elutriated with PAS, which may have resulted in less collection injury. When Spectra and Trima platelets were stored in Haemonetics' bags, poststorage viability was significantly improved. Platelet viability is better maintained in vitro than in vivo, allowing substantial increases in platelet storage times. However, implementation will require resolution of potential bacterial overgrowth during storage.

  11. Experimental study on agitated drying characteristics of sewage sludge under the effects of different additive agents.

    PubMed

    Deng, Wenyi; Su, Yaxin

    2014-07-01

    Drying experiments of dewatered sewage sludge (DSS) were conducted on a agitated paddle dryer, and the effects of additive agents, i.e., CaO, pulverized coal (PC), heavy oil (HO), and dried sludge ("DS" through back mixing) on the agitated drying characteristics of DSS were investigated. The results indicated that CaO can significantly increase the drying rate of DSS. The drying rate at CaO/DSS (mass ratio)=1/100 was 135% higher than that of CaO/DSS=0. Pulverized coal has no obvious effect on drying rate, but the increase of PC/DSS can promote breaking up of sludge lump. Heavy oil was found to be slightly effective in improving the drying rate of DSS in the examined experimental range of HO/DSS=0-1/20. It is also found that HO can reduce the torque of the dryer shaft, due to its lubrication effect. Back mixing of DS was found to be effective in alleviating the unfavorable effect of the lumpy phase by improving the mixing effect of the paddle dryer. There was a marked increase of drying rate with an increase of the DS/DSS in the experimental range of DS/DSS=0-1/3.

  12. Generalized linear and generalized additive models in studies of species distributions: Setting the scene

    USGS Publications Warehouse

    Guisan, A.; Edwards, T.C.; Hastie, T.

    2002-01-01

    An important statistical development of the last 30 years has been the advance in regression analysis provided by generalized linear models (GLMs) and generalized additive models (GAMs). Here we introduce a series of papers prepared within the framework of an international workshop entitled: Advances in GLMs/GAMs modeling: from species distribution to environmental management, held in Riederalp, Switzerland, 6-11 August 2001. We first discuss some general uses of statistical models in ecology, as well as provide a short review of several key examples of the use of GLMs and GAMs in ecological modeling efforts. We next present an overview of GLMs and GAMs, and discuss some of their related statistics used for predictor selection, model diagnostics, and evaluation. Included is a discussion of several new approaches applicable to GLMs and GAMs, such as ridge regression, an alternative to stepwise selection of predictors, and methods for the identification of interactions by a combined use of regression trees and several other approaches. We close with an overview of the papers and how we feel they advance our understanding of their application to ecological modeling. ?? 2002 Elsevier Science B.V. All rights reserved.

  13. Study on additional carrier sensing for IEEE 802.15.4 wireless sensor networks.

    PubMed

    Lee, Bih-Hwang; Lai, Ruei-Lung; Wu, Huai-Kuei; Wong, Chi-Ming

    2010-01-01

    Wireless sensor networks based on the IEEE 802.15.4 standard are able to achieve low-power transmissions in the guise of low-rate and short-distance wireless personal area networks (WPANs). The slotted carrier sense multiple access with collision avoidance (CSMA/CA) is used for contention mechanism. Sensor nodes perform a backoff process as soon as the clear channel assessment (CCA) detects a busy channel. In doing so they may neglect the implicit information of the failed CCA detection and further cause the redundant sensing. The blind backoff process in the slotted CSMA/CA will cause lower channel utilization. This paper proposes an additional carrier sensing (ACS) algorithm based on IEEE 802.15.4 to enhance the carrier sensing mechanism for the original slotted CSMA/CA. An analytical Markov chain model is developed to evaluate the performance of the ACS algorithm. Both analytical and simulation results show that the proposed algorithm performs better than IEEE 802.15.4, which in turn significantly improves throughput, average medium access control (MAC) delay and power consumption of CCA detection.

  14. Food additives

    PubMed Central

    Spencer, Michael

    1974-01-01

    Food additives are discussed from the food technology point of view. The reasons for their use are summarized: (1) to protect food from chemical and microbiological attack; (2) to even out seasonal supplies; (3) to improve their eating quality; (4) to improve their nutritional value. The various types of food additives are considered, e.g. colours, flavours, emulsifiers, bread and flour additives, preservatives, and nutritional additives. The paper concludes with consideration of those circumstances in which the use of additives is (a) justified and (b) unjustified. PMID:4467857

  15. Lesion removal and lesion addition algorithms in lung volumetric data sets for perception studies

    NASA Astrophysics Data System (ADS)

    Madsen, Mark T.; Berbaum, Kevin S.; Ellingson, Andrew; Thompson, Brad H.; Mullan, Brian F.

    2006-03-01

    Image perception studies of medical images provide important information about how radiologists interpret images and insights for reducing reading errors. In the past, perception studies have been difficult to perform using clinical imaging studies because of the problems associated with obtaining images demonstrating proven abnormalities and appropriate normal control images. We developed and evaluated interactive software that allows the seamless removal of abnormal areas from CT lung image sets. We have also developed interactive software for capturing lung lesions in a database where they can be added to lung CT studies. The efficacy of the software to remove abnormal areas of lung CT studies was evaluated psychophysically by having radiologists select the one altered image from a display of four. The software for adding lesions was evaluated by having radiologists classify displayed CT slices with lesions as real or artificial scaled to 3 levels of confidence. The results of these experiments demonstrated that the radiologist had difficulty in distinguishing the raw clinical images from those that had been altered. We conclude that this software can be used to create experimental normal control and "proven" lesion data sets for volumetric CT of the lung fields. We also note that this software can be easily adapted to work with other tissue besides lung and that it can be adapted to other digital imaging modalities.

  16. Comparative genomics study of polyhydroxyalkanoates (PHA) and ectoine relevant genes from Halomonas sp. TD01 revealed extensive horizontal gene transfer events and co-evolutionary relationships

    PubMed Central

    2011-01-01

    Background Halophilic bacteria have shown their significance in industrial production of polyhydroxyalkanoates (PHA) and are gaining more attention for genetic engineering modification. Yet, little information on the genomics and PHA related genes from halophilic bacteria have been disclosed so far. Results The draft genome of moderately halophilic bacterium, Halomonas sp. TD01, a strain of great potential for industrial production of short-chain-length polyhydroxyalkanoates (PHA), was analyzed through computational methods to reveal the osmoregulation mechanism and the evolutionary relationship of the enzymes relevant to PHA and ectoine syntheses. Genes involved in the metabolism of PHA and osmolytes were annotated and studied in silico. Although PHA synthase, depolymerase, regulator/repressor and phasin were all involved in PHA metabolic pathways, they demonstrated different horizontal gene transfer (HGT) events between the genomes of different strains. In contrast, co-occurrence of ectoine genes in the same genome was more frequently observed, and ectoine genes were more likely under coincidental horizontal gene transfer than PHA related genes. In addition, the adjacent organization of the homologues of PHA synthase phaC1 and PHA granule binding protein phaP was conserved in the strain TD01, which was also observed in some halophiles and non-halophiles exclusively from γ-proteobacteria. In contrast to haloarchaea, the proteome of Halomonas sp. TD01 did not show obvious inclination towards acidity relative to non-halophilic Escherichia coli MG1655, which signified that Halomonas sp. TD01 preferred the accumulation of organic osmolytes to ions in order to balance the intracellular osmotic pressure with the environment. Conclusions The accessibility of genome information would facilitate research on the genetic engineering of halophilic bacteria including Halomonas sp. TD01. PMID:22040376

  17. Quantum chemical study of relative reactivities of a series of amines and nitriles - Relevance to prebiotic chemistry

    NASA Technical Reports Server (NTRS)

    Loew, G. H.; Berkowitz, D.; Chang, S.

    1975-01-01

    Using the Iterative Extended Huckel Theory (IEHT) calculations of the electron distribution and orbital energies of a series of thirteen amines, nitriles and amino-nitriles relevant to prebiotic and cosmo-chemistry have been carried out. Ground state properties such as the energy and nature of the highest occupied (HOMO) and lowest empty (LEMO) molecular orbitals, net atomic charges and number of nonbonding electrons have been identified as criteria for correlating the relative nucleophilicity of amine and nitrile nitrogens and the electrophilicity of nitrile and other unsaturated carbon atoms. The results of such correlations can be partially verified by known chemical behavior of these compounds and are used to predict and understand their role in prebiotic organic synthesis.

  18. Additional Study of Water Droplet Median Volume Diameter (MVD) Effects on Ice Shapes

    NASA Technical Reports Server (NTRS)

    Tsao, Jen-Ching; Anderson, David N.

    2005-01-01

    This paper reports the result of an experimental study in the NASA Glenn Icing Research Tunnel (IRT) to evaluate how well the MVD-independent effect identified previously might apply to SLD conditions in rime icing situations. Models were NACA 0012 wing sections with chords of 53.3 and 91.4 cm. Tests were conducted with a nominal airspeed of 77 m/s (150 kt) and a number of MVD's ranging from 15 to 100 m with LWC of 0.5 to 1 g/cu m. In the present study, ice shapes recorded from past studies and recent results at SLD and Appendix-C conditions are reviewed to show that droplet diameter is not important to rime ice shape for MVD of 30 microns or larger, but for less than 30 m drop sizes a rime ice shape transition from convex to wedge to spearhead type ice shape is observed.

  19. Study on Type C Coal Fly ash as an Additive to Molding Sand for Steel Casting

    NASA Astrophysics Data System (ADS)

    Palaniappan, Jayanthi

    2017-04-01

    Study of physio-chemical properties studies such as granulometric analysis, moisture, X ray fluorescence etc. were performed with Type C coal—combustion fly ash to investigate their potential as a distinct option for molding sand in foundry, thereby reducing the dependency on latter. Technological properties study such as compressive strength, tensile strength, permeability and compaction of various compositions of fly ash molding sand (10, 20 and 30 % fly ash substitute to chemically bonded sand) were performed and compared with silica molding sand. Steel casting production using this fly ash molding sand was done and the casting surface finish and typical casting parameters were assessed. It was noted that a good quality steel casting could be produced using type C fly ash molding sand, which effectively replaced 20 % of traditional molding sand and binders thereby providing greater financial profits to the foundry and an effective way of fly ash utilization (waste management).

  20. Voice measures of workload in the advanced flight deck: Additional studies

    NASA Technical Reports Server (NTRS)

    Schneider, Sid J.; Alpert, Murray

    1989-01-01

    These studies investigated acoustical analysis of the voice as a measure of workload in individual operators. In the first study, voice samples were recorded from a single operator during high, medium, and low workload conditions. Mean amplitude, frequency, syllable duration, and emphasis all tended to increase as workload increased. In the second study, NASA test pilots performed a laboratory task, and used a flight simulator under differing work conditions. For two of the pilots, high workload in the simulator brought about greater amplitude, peak duration, and stress. In both the laboratory and simulator tasks, high workload tended to be associated with more statistically significant drop-offs in the acoustical measures than were lower workload levels. There was a great deal of intra-subject variability in the acoustical measures. The results suggested that in individual operators, increased workload might be revealed by high initial amplitude and frequency, followed by rapid drop-offs over time.

  1. Study on Type C Coal Fly ash as an Additive to Molding Sand for Steel Casting

    NASA Astrophysics Data System (ADS)

    Palaniappan, Jayanthi

    2016-05-01

    Study of physio-chemical properties studies such as granulometric analysis, moisture, X ray fluorescence etc. were performed with Type C coal—combustion fly ash to investigate their potential as a distinct option for molding sand in foundry, thereby reducing the dependency on latter. Technological properties study such as compressive strength, tensile strength, permeability and compaction of various compositions of fly ash molding sand (10, 20 and 30 % fly ash substitute to chemically bonded sand) were performed and compared with silica molding sand. Steel casting production using this fly ash molding sand was done and the casting surface finish and typical casting parameters were assessed. It was noted that a good quality steel casting could be produced using type C fly ash molding sand, which effectively replaced 20 % of traditional molding sand and binders thereby providing greater financial profits to the foundry and an effective way of fly ash utilization (waste management).

  2. Computational study of collisions between O(3P) and NO(2Π) at temperatures relevant to the hypersonic flight regime

    NASA Astrophysics Data System (ADS)

    Castro-Palacio, Juan Carlos; Nagy, Tibor; Bemish, Raymond J.; Meuwly, Markus

    2014-10-01

    Reactions involving N and O atoms dominate the energetics of the reactive air flow around spacecraft when reentering the atmosphere in the hypersonic flight regime. For this reason, the thermal rate coefficients for reactive processes involving O(3P) and NO(2Π) are relevant over a wide range of temperatures. For this purpose, a potential energy surface (PES) for the ground state of the NO2 molecule is constructed based on high-level ab initio calculations. These ab initio energies are represented using the reproducible kernel Hilbert space method and Legendre polynomials. The global PES of NO2 in the ground state is constructed by smoothly connecting the surfaces of the grids of various channels around the equilibrium NO2 geometry by a distance-dependent weighting function. The rate coefficients were calculated using Monte Carlo integration. The results indicate that at high temperatures only the lowest A-symmetry PES is relevant. At the highest temperatures investigated (20 000 K), the rate coefficient for the "O1O2+N" channel becomes comparable (to within a factor of around three) to the rate coefficient of the oxygen exchange reaction. A state resolved analysis shows that the smaller the vibrational quantum number of NO in the reactants, the higher the relative translational energy required to open it and conversely with higher vibrational quantum number, less translational energy is required. This is in accordance with Polanyi's rules. However, the oxygen exchange channel (NO2+O1) is accessible at any collision energy. Finally, this work introduces an efficient computational protocol for the investigation of three-atom collisions in general.

  3. Computational study of collisions between O(3P) and NO(2Π) at temperatures relevant to the hypersonic flight regime.

    PubMed

    Castro-Palacio, Juan Carlos; Nagy, Tibor; Bemish, Raymond J; Meuwly, Markus

    2014-10-28

    Reactions involving N and O atoms dominate the energetics of the reactive air flow around spacecraft when reentering the atmosphere in the hypersonic flight regime. For this reason, the thermal rate coefficients for reactive processes involving O((3)P) and NO((2)Π) are relevant over a wide range of temperatures. For this purpose, a potential energy surface (PES) for the ground state of the NO2 molecule is constructed based on high-level ab initio calculations. These ab initio energies are represented using the reproducible kernel Hilbert space method and Legendre polynomials. The global PES of NO2 in the ground state is constructed by smoothly connecting the surfaces of the grids of various channels around the equilibrium NO2 geometry by a distance-dependent weighting function. The rate coefficients were calculated using Monte Carlo integration. The results indicate that at high temperatures only the lowest A-symmetry PES is relevant. At the highest temperatures investigated (20,000 K), the rate coefficient for the "O1O2+N" channel becomes comparable (to within a factor of around three) to the rate coefficient of the oxygen exchange reaction. A state resolved analysis shows that the smaller the vibrational quantum number of NO in the reactants, the higher the relative translational energy required to open it and conversely with higher vibrational quantum number, less translational energy is required. This is in accordance with Polanyi's rules. However, the oxygen exchange channel (NO2+O1) is accessible at any collision energy. Finally, this work introduces an efficient computational protocol for the investigation of three-atom collisions in general.

  4. Theoretical studies of nonadiabatic and spin-forbidden processes: Investigations of the reactions and spectroscopy of radical species relevant to combustion reactions and diagnostics

    SciTech Connect

    Yarkony, D.R.

    1993-12-01

    This research program focusses on studies of spin-forbidden and electronically nonadiabatic processes involving radical species relevant to combustion reactions and combustion diagnostics. To study the electronic structure aspects of these processes a unique and powerful system of electronic structure programs, developed over the past nine years, the BROOKLYN codes, is employed. These programs enable the authors to address questions basic to the understanding of elementary combustion processes not tractable using more standard quantum chemistry codes.

  5. A Micro-Developmental Approach to Studying Young Children's Problem Solving Behavior in Addition

    ERIC Educational Resources Information Center

    Voutsina, Chronoula

    2012-01-01

    This paper presents a study that investigated the process of change in 5-6-year-old children's successful problem-solving approaches when tackling a multiple-step task in elementary arithmetic. Micro-developmental changes in children's successful problem-solving behavior were analyzed using Karmiloff-Smith's model of representational redescription…

  6. Genome-Wide Association Study of Intelligence: Additive Effects of Novel Brain Expressed Genes

    ERIC Educational Resources Information Center

    Loo, Sandra K.; Shtir, Corina; Doyle, Alysa E.; Mick, Eric; McGough, James J.; McCracken, James; Biederman, Joseph; Smalley, Susan L.; Cantor, Rita M.; Faraone, Stephen V.; Nelson, Stanley F.

    2012-01-01

    Objective: The purpose of the present study was to identify common genetic variants that are associated with human intelligence or general cognitive ability. Method: We performed a genome-wide association analysis with a dense set of 1 million single-nucleotide polymorphisms (SNPs) and quantitative intelligence scores within an ancestrally…

  7. A Study of the Effect of Additional Reading Assistance on Student Achievement

    ERIC Educational Resources Information Center

    Gillan-Sanderson, Nicole A.

    2012-01-01

    This study describes a procedure one school district used to increase students' reading abilities through reviewing data and adjusting the instruction to give students intensive services, as needed. This school worked in a problem-solving team approach to develop a comprehensive team that followed the progression of student achievement.…

  8. Nahuatl as a Classical, Foreign, and Additional Language: A Phenomenological Study

    ERIC Educational Resources Information Center

    De Felice, Dustin

    2012-01-01

    In this study, participants learning an endangered language variety shared their experiences, thoughts, and feelings about the often complex and diverse language-learning process. I used phenomenological interviews in order to learn more about these English or Spanish language speakers' journey with the Nahuatl language. From first encounter to…

  9. CNV-based genome wide association study reveals additional variants contributing to meat quality in swine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pork quality is important both to the meat processing industry and consumers’ purchasing attitudes. Copy number variation (CNV) is a burgeoning kind of variant that may influence meat quality. Herein, a genome-wide association study (GWAS) was performed between CNVs and meat quality traits in swine....

  10. A QUESTIONNAIRE TO ASSESS THE RELEVANCE AND CREDIBILITY OF OBSERVATIONAL STUDIES TO INFORM HEALTH CARE DECISION MAKING: AN ISPOR-AMCP-NPC GOOD PRACTICE TASK FORCE REPORT

    PubMed Central

    Berger, Marc L; Martin, Bradley C; Husereau, Don; Worley, Karen; Allen, Dan; Yang, Winnie; Mullins, C. Daniel; Kahler, Kristijan; Quon, Nicole C.; Devine, Scott; Graham, John; Cannon, Eric; Crown, William

    2014-01-01

    Evidence-based healthcare decisions are best informed by comparisons of all relevant interventions used to treat conditions in specific patient populations. Observational studies are being performed to help fill evidence gaps. However, widespread adoption of evidence from observational studies has been limited due to a variety of factors, including the lack of consensus regarding accepted principles for their evaluation and interpretation. Two Task Forces were formed to develop questionnaires to assist decision makers in evaluating observational studies, with one Task Force addressing retrospective research and the other prospective research. The intent was to promote a structured approach to reduce the potential for subjective interpretation of evidence and drive consistency in decision-making. Separately developed questionnaires were combined into a single questionnaire consisting of 33 items. These were divided into two domains: relevance and credibility. Relevance addresses the extent to which findings, if accurate, apply to the setting of interest to the decision maker. Credibility addresses the extent to which the study findings accurately answer the study question. The questionnaire provides a guide for assessing the degree of confidence that should be placed from observational studies and promotes awareness of the subtleties involved in evaluating those. PMID:24636373

  11. Thermal analysis studies of Ge additive of Se-Te glasses

    NASA Astrophysics Data System (ADS)

    Mohamed, M.; Abdel-Rahim, M. A.

    2016-04-01

    Ge x Se50Te50- x ( x = 5, 15, 20, 35 at.%) bulk glasses were synthesized by the melt quenching method. The amorphous nature of the investigated glasses was determined by X-ray diffraction. Results of differential scanning calorimetry (DSC) of the studied compositions under non-isothermal conditions were reported and discussed. The glass transition temperature ( T g), onset crystallization temperature ( T c), and crystallization peak temperature ( T p) were determined from DSC traces at different heating rates. It was found that the values of T g, T c, and T p rely on both composition and heating rate. A double crystallization stages were observed in the DSC results. Various kinetics parameters such as the glass transition energy ( E g), crystallization activation energy ( E c), and rate constant ( K p) were calculated. The glass-forming ability of the studied compositions was discussed as function of the determined kinetics parameters.

  12. Comparative study of glycine single crystals with additive of potassium nitrate in different concentration ratios

    NASA Astrophysics Data System (ADS)

    Gujarati, Vivek P.; Deshpande, M. P.; Patel, Kamakshi R.; Chaki, S. H.

    2016-05-01

    Semi-organic crystals of Glycine Potassium Nitrate (GPN) with potential applications in Non linear optics (NLO) were grown using slow evaporation technique. Glycine and Potassium Nitrate were taken in three different concentration ratios of 3:1, 2:1 and 1:1 respectively. We checked the solubility of the material in distilled water at different temperatures and could observe the growth of crystals in 7 weeks time. Purity of the grown crystals was confirmed by Energy Dispersive X-ray Analysis (EDAX) and CHN analysis. GSN Powder X-ray diffraction pattern was recorded to confirm the crystalline nature. To confirm the applications of grown crystals in opto-electronics field, UV-Vis-NIR study was carried out. Dielectric properties of the samples were studied in between the frequency range 1Hz to 100 KHz.

  13. Brief reconnaissance study for the addition of hydropower for Carr Fork Dam, Sassafras, Kentucky

    SciTech Connect

    Gebhard, T.G. Jr.

    1982-05-24

    The feasibility of retrofitting the Carr Fork Dam near Hazard, KY for power generation was examined. This dam has a developable head of 80 ft and was built in 1975 to provide flood protection. The study of environmental, institutional, safety, and economic factors showed that the total investment cost would be $909,600 and that hydroelectric power development at this site is not feasible unless a higher price could be obtained for the power sold. (LCL)

  14. Brief reconnaissance study for the addition of hydropower for Spray Dam, Eden, North Carolina

    SciTech Connect

    Gebhard, T.G. Jr.

    1981-01-30

    The feasibility of retrofitting the Spray Dam near Eden, North Carolina for power generation was examined. This dam has a developable head of 10 ft., was built in 1898 for hydroelectric power generation with one of 2 installed units currently operating. The study of environmental, institutional, safety and economic factors showed that hydroelectric power development at this site is possible and that the economics of retrofits will depend on whether existing equipment can be repaired or will have to be replaced. (LCL)

  15. Additional studies of sheep haemopexin: genetic control, frequencies and postnatal development.

    PubMed

    Stratil, A; Bobák, P; Margetín, M; Glasnák, V

    1989-01-01

    This study presents evidence that sheep haemopexin phenotypes are genetically controlled by three alleles, HpxA, HpxB1 and HpxB2, of a single autosomal locus. Frequencies of two alleles, HpxA and HpxB (HpxB encompasses two isoalleles, HpxB1 and HpxB2), were studied in eight sheep breeds in Czechoslovakia. The frequency of the HpxA allele was highest (ranging from 0.81 in Merino to 1.0 in East Friesian sheep). Qualitative and quantitative changes in haemopexin during postnatal development were studied by starch gel electrophoresis and rocket immunoelectrophoresis respectively. In electrophoresis, 1- or 2-day-old lambs had two very weak zones corresponding in mobility to two slower zones of adult animals. Later, the third more anodic zone appeared and gradually increased in intensity. In 1-month-old lambs the patterns were practically identical with those of adult animals. Using rocket immunoelectrophoresis, the level of haemopexin shortly after birth was practically zero. It rose sharply till the sixth day of life; then the level continued to rise slowly till about 1 month of age. The mean haemopexin level in adult sheep was 64.5 +/- 18.26 (SD) mg/100ml serum, ranging from 30.5 to 116.5 mg/100ml.

  16. A clinical comparative study of Cadiax Compact II and intraoral records using wax and addition silicone.

    PubMed

    Torabi, Kianoosh; Pour, Sasan Rasaei; Ahangari, Ahmad Hassan; Ghodsi, Safoura

    2014-01-01

    Evaluation of mandibular movements is necessary to form the occlusal anatomical contour, analyze the temporomandibular joint status, and evaluate the patient's occlusion. This clinical study was conducted to compare the mandibular recording device Cadiax Compact II with routine intraoral records for measuring condylar inclinations. The results showed that the differences between Cadiax and intraoral records were statistically significant for all measurements. Cadiax measurements had a stronger correlation with silicone records. The quantities of recorded Bennett angles were lower and the values of sagittal condylar inclination were higher with Cadiax than with routine intraoral records.

  17. [Anatomical and radiological studies on additional mandible teeth anesthesia considering innervation variability].

    PubMed

    Tarasenko, S V; Dydykin, S S; Kuzin, A V

    2013-01-01

    The paper presents studies on nutritional foramina of the mandible. Some nutritional foramina located in the frontal mandibular region on the lingual surface and containing significant blood vessels and nerves are found to be more typical for teeth-bearing mandible. In retromolar area in case of third molars presence intraosseous canals were revealed leading to inferior alveolar nerve canal. One should consider intraligamental and lingual anesthesia by lower incisors extraction. Intraosseous anesthesia and retromolar area infiltration significantly increase anesthesia efficiency by third molar extraction.

  18. Relevance of electronic health information to doctors in the developing world: results of the Ptolemy Project's Internet-based Health Information Study (IBHIS).

    PubMed

    Burton, Kirsteen R; Howard, Andrew; Beveridge, Massey

    2005-09-01

    The aim of this study was to determine the current usage, relevance, and preferences for electronic health information (EHI) in the participant surgeons' clinical, research, and teaching activities. The Internet-Based Health Information Survey (IBHIS) was conducted from August to December 2003. Thirty-seven doctors (primarily practicing in East Africa) participated, all of whom had been using the Ptolemy resources for at least 6 months. Survey questions concerned time spent reading medical literature, preferred information sources, preferred type of publication, relevance, preference for western versus local medical literature, and academic productivity. Among the 75 eligible participants, 37 (48%) responded. From these responses it was found that African surgeons with access to EHI read more than articles than they did before they had such access, and they find that the information obtained is highly relevant to their clinical, teaching, and research activities. They prefer electronic journals to textbooks and are more inclined to change their practice based on information found in western journals than local journals. Ptolemy resources helped the respondents who reported academic work write a total of 33 papers for presentation or publication. Overall, access to EHI enables doctors in Africa to read more, is relevant, and contributes directly to academic productivity; thus Western medical literature is useful in the developing world, and EHI delivery should continue to expand.

  19. Study on the interaction of the toxic food additive carmoisine with serum albumins: a microcalorimetric investigation.

    PubMed

    Basu, Anirban; Kumar, Gopinatha Suresh

    2014-05-30

    The interaction of the synthetic azo dye and food colorant carmoisine with human and bovine serum albumins was studied by microcalorimetric techniques. A complete thermodynamic profile of the interaction was obtained from isothermal titration calorimetry studies. The equilibrium constant of the complexation process was of the order of 10(6)M(-1) and the binding stoichiometry was found to be 1:1 with both the serum albumins. The binding was driven by negative standard molar enthalpy and positive standard molar entropy contributions. The binding affinity was lower at higher salt concentrations in both cases but the same was dominated by mostly non-electrostatic forces at all salt concentrations. The polyelectrolytic forces contributed only 5-8% of the total standard molar Gibbs energy change. The standard molar enthalpy change enhanced whereas the standard molar entropic contribution decreased with rise in temperature but they compensated each other to keep the standard molar Gibbs energy change almost invariant. The negative standard molar heat capacity values suggested the involvement of a significant hydrophobic contribution in the complexation process. Besides, enthalpy-entropy compensation phenomenon was also observed in both the systems. The thermal stability of the serum proteins was found to be remarkably enhanced on binding to carmoisine.

  20. Are gastric hyperplastic polyps an additional manifestation in celiac disease?: Results from a retrospective study.

    PubMed

    Dore, Maria Pina; Pes, Giovanni Mario; Rocchi, Chiara; Loria, Maria Francesca; Soro, Sara; Bassotti, Gabrio

    2017-02-01

    Gastric polyps are frequently reported in patients undergoing upper endoscopic procedures. In this retrospective study, the association between hyperplastic polyps and celiac disease in Northern Sardinia was estimated.Age, gender, body mass index, and medications taken in the 2 preceding months, including proton-pump inhibitors (PPIs), H2 receptor blockers (anti-H2), Helicobacter pylori status, endoscopic findings, and histology from charts of patients undergoing esophago-gastro-duodenoscopy were reviewed. Polyps were classified as hyperplastic, fundic gland, inflammatory, and adenomatous.3.7% (423/11379) patients had celiac disease. Prevalence of gastric polyps was 4.2% (3.8% among celiac vs 4.2% nonceliac patients). Inflammatory polyp was the most common histotype (55.8% and 56.2%) followed by fundic gland polyps (31.4% and 43.7%), hyperplastic (8.7% and 0%), and adenomas, in celiac and nonceliac patients, respectively. Fundic gland polyps were more common in PPI users (odds ratio: 4.06) than in nonusers (2.65, P = 0.001) among celiac and nonceliac patients. Age older than 50, female gender, esophago-gastro-duodenoscopy year, and PPI use were associated with the presence of polyps, whereas active H pylori infection was not.Gastric polyps were common in Sardinian patients undergoing esophago-gastro-duodenoscopy. However, the previously reported association between hyperplastic polyps and celiac disease was not confirmed in our study.

  1. [Chewing gum as an additional agent in maintaining oral hygiene versus smoking status--preliminary study].

    PubMed

    Nakonieczna-Rudnicka, Marta; Strycharz-Dudziak, Małgorzata; Bachanek, Teresa

    2012-01-01

    Nowadays chewing gum is widely used in different age groups, so complying with proper duration and frequency of chewing is an important factor influencing the state of masticatory system. The study involved 112 dental students of the Medical University of Lublin. Everyday use of chewing gum declared 47,32% of cases. Chewing time up to 10 minutes was stated in 23,08% of respondents, 11-20 minutes in 40,38% of interviewees. Among the examined students 17,3% smoked cigarettes. In smokers group 83,33% of questioned chewed the gum every day, while among non-smokers - 43,37%. Chewing time shorter than 10 minutes declared 22,22% of smokers and 23,26% of non-smokers, while chewing time between 11-20 minutes - 27,78% i 44,35% of smokers and non-smokers respectively. Obtained results indicate the need of carrying out further studies aimed at the nicotine influence on saliva parameters with respect to development of diseases of hard tooth tissues.

  2. Shelf life and quality study of minced tilapia with Nori and Hijiki seaweeds as natural additives.

    PubMed

    Ribeiro, Ingridy Simone; Shirahigue, Ligianne Din; Ferraz de Arruda Sucasas, Lia; Anbe, Lika; da Cruz, Pedro Gomes; Gallo, Cláudio Rosa; Carpes, Solange Teresinha; Marques, Marcos José; Oetterer, Marília

    2014-01-01

    The extraction of mechanically separated meat has emerged as an attractive process. However, it increases the incorporation of oxygen and, consequently, of flavors due to rancidity. Thus, preservatives must be added. The objective of this study was to evaluate the shelf life of minced tilapia to replace synthetic preservatives with Hijiki and Nori seaweeds extracts. The application of the extracts had no effect on the chemical composition of the minced tilapia. The seaweed extracts had inhibitory effect on total volatile base nitrogen. The minced tilapia complied with the microbiological standard set by Brazilin law. The panelists detected no differences in the rancid aroma and only minor differences were detected in the color of the products. It can be concluded that the minced tilapia with added seaweed extracts were within quality standards during frozen storage.

  3. Additional results for 'Sequential design approaches for bioequivalence studies with crossover designs'.

    PubMed

    Montague, Timothy H; Potvin, Diane; Diliberti, Charles E; Hauck, Walter W; Parr, Alan F; Schuirmann, Donald J

    2012-01-01

    In 2008, this group published a paper on approaches for two-stage crossover bioequivalence (BE) studies that allowed for the reestimation of the second-stage sample size based on the variance estimated from the first-stage results. The sequential methods considered used an assumed GMR of 0.95 as part of the method for determining power and sample size. This note adds results for an assumed GMR = 0.90. Two of the methods recommended for GMR = 0.95 in the earlier paper have some unacceptable increases in Type I error rate when the GMR is changed to 0.90. If a sponsor wants to assume 0.90 for the GMR, Method D is recommended. Copyright © 2011 John Wiley & Sons, Ltd.

  4. Shelf Life and Quality Study of Minced Tilapia with Nori and Hijiki Seaweeds as Natural Additives

    PubMed Central

    Ribeiro, Ingridy Simone; Shirahigue, Ligianne Din; Ferraz de Arruda Sucasas, Lia; Anbe, Lika; da Cruz, Pedro Gomes; Gallo, Cláudio Rosa; Carpes, Solange Teresinha; Marques, Marcos José; Oetterer, Marília

    2014-01-01

    The extraction of mechanically separated meat has emerged as an attractive process. However, it increases the incorporation of oxygen and, consequently, of flavors due to rancidity. Thus, preservatives must be added. The objective of this study was to evaluate the shelf life of minced tilapia to replace synthetic preservatives with Hijiki and Nori seaweeds extracts. The application of the extracts had no effect on the chemical composition of the minced tilapia. The seaweed extracts had inhibitory effect on total volatile base nitrogen. The minced tilapia complied with the microbiological standard set by Brazilin law. The panelists detected no differences in the rancid aroma and only minor differences were detected in the color of the products. It can be concluded that the minced tilapia with added seaweed extracts were within quality standards during frozen storage. PMID:25478593

  5. Biological effect of food additive titanium dioxide nanoparticles on intestine: an in vitro study.

    PubMed

    Song, Zheng-Mei; Chen, Ni; Liu, Jia-Hui; Tang, Huan; Deng, Xiaoyong; Xi, Wen-Song; Han, Kai; Cao, Aoneng; Liu, Yuanfang; Wang, Haifang

    2015-10-01

    Titanium dioxide nanoparticles (TiO2 NPs) are widely found in food-related consumer products. Understanding the effect of TiO2 NPs on the intestinal barrier and absorption is essential and vital for the safety assessment of orally administrated TiO2 NPs. In this study, the cytotoxicity and translocation of two native TiO2 NPs, and these two TiO2 NPs pretreated with the digestion simulation fluid or bovine serum albumin were investigated in undifferentiated Caco-2 cells, differentiated Caco-2 cells and Caco-2 monolayer. TiO2 NPs with a concentration less than 200 µg ml(-1) did not induce any toxicity in differentiated cells and Caco-2 monolayer after 24 h exposure. However, TiO2 NPs pretreated with digestion simulation fluids at 200 µg ml(-1) inhibited the growth of undifferentiated Caco-2 cells. Undifferentiated Caco-2 cells swallowed native TiO2 NPs easily, but not pretreated NPs, implying the protein coating on NPs impeded the cellular uptake. Compared with undifferentiated cells, differentiated ones possessed much lower uptake ability of these TiO2 NPs. Similarly, the traverse of TiO2 NPs through the Caco-2 monolayer was also negligible. Therefore, we infer the possibility of TiO2 NPs traversing through the intestine of animal or human after oral intake is quite low. This study provides valuable information for the risk assessment of TiO2 NPs in food.

  6. On the Relevance of Natural Stimuli for the Study of Brainstem Correlates: The Example of Consonance Perception

    PubMed Central

    Cousineau, Marion; Bidelman, Gavin M.; Peretz, Isabelle; Lehmann, Alexandre

    2015-01-01

    Some combinations of musical tones sound pleasing to Western listeners, and are termed consonant, while others sound discordant, and are termed dissonant. The perceptual phenomenon of consonance has been traced to the acoustic property of harmonicity. It has been repeatedly shown that neural correlates of consonance can be found as early as the auditory brainstem as reflected in the harmonicity of the scalp-recorded frequency-following response (FFR). “Neural Pitch Salience” (NPS) measured from FFRs—essentially a time-domain equivalent of the classic pattern recognition models of pitch—has been found to correlate with behavioral judgments of consonance for synthetic stimuli. Following the idea that the auditory system has evolved to process behaviorally relevant natural sounds, and in order to test the generalizability of this finding made with synthetic tones, we recorded FFRs for consonant and dissonant intervals composed of synthetic and natural stimuli. We found that NPS correlated with behavioral judgments of consonance and dissonance for synthetic but not for naturalistic sounds. These results suggest that while some form of harmonicity can be computed from the auditory brainstem response, the general percept of consonance and dissonance is not captured by this measure. It might either be represented in the brainstem in a different code (such as place code) or arise at higher levels of the auditory pathway. Our findings further illustrate the importance of using natural sounds, as a complementary tool to fully-controlled synthetic sounds, when probing auditory perception. PMID:26720000

  7. On the Relevance of Natural Stimuli for the Study of Brainstem Correlates: The Example of Consonance Perception.

    PubMed

    Cousineau, Marion; Bidelman, Gavin M; Peretz, Isabelle; Lehmann, Alexandre

    2015-01-01

    Some combinations of musical tones sound pleasing to Western listeners, and are termed consonant, while others sound discordant, and are termed dissonant. The perceptual phenomenon of consonance has been traced to the acoustic property of harmonicity. It has been repeatedly shown that neural correlates of consonance can be found as early as the auditory brainstem as reflected in the harmonicity of the scalp-recorded frequency-following response (FFR). "Neural Pitch Salience" (NPS) measured from FFRs-essentially a time-domain equivalent of the classic pattern recognition models of pitch-has been found to correlate with behavioral judgments of consonance for synthetic stimuli. Following the idea that the auditory system has evolved to process behaviorally relevant natural sounds, and in order to test the generalizability of this finding made with synthetic tones, we recorded FFRs for consonant and dissonant intervals composed of synthetic and natural stimuli. We found that NPS correlated with behavioral judgments of consonance and dissonance for synthetic but not for naturalistic sounds. These results suggest that while some form of harmonicity can be computed from the auditory brainstem response, the general percept of consonance and dissonance is not captured by this measure. It might either be represented in the brainstem in a different code (such as place code) or arise at higher levels of the auditory pathway. Our findings further illustrate the importance of using natural sounds, as a complementary tool to fully-controlled synthetic sounds, when probing auditory perception.

  8. Assessing the Relevance of in vitro Studies in Nanotoxicology by Examining Correlations between in vitro and in vivo Data

    PubMed Central

    Han, Xianglu; Corson, Nancy; Wade-Mercer, Pamela; Gelein, Robert; Jiang, Jingkun; Sahu, Manoranjan; Biswas, Pratim; Finkelstein, Jacob N.; Elder, Alison; Oberdörster, Günter

    2012-01-01

    There is an urgent need for in vitro screening assays to evaluate nanoparticle (NP) toxicity. However, the relevance of in vitro assays is still disputable. We administered doses of TiO2 NPs of different sizes to alveolar epithelial cells in vitro and the same NPs by intratracheal instillation in rats in vivo to examine the correlation between in vitro and in vivo responses. The correlations were based on toxicity rankings of NPs after adopting NP surface area as dose metric, and response per unit surface area as response metric. Sizes of the anatase TiO2 NPs ranged from 3 to 100 nm. A cell-free assay for measuring reactive oxygen species (ROS) was used, and lactate dehydrogenase (LDH) release, and protein oxidation induction were the in vitro cellular assays using a rat lung Type I epithelial cell line (R3/1) following 24 hr incubation. The in vivo endpoint was number of PMNs in bronchoalveolar lavage fluid (BALF) after exposure of rats to the NPs via intratracheal instillation. Slope analyses of the dose response curves shows that the in vivo and in vitro responses were well correlated. We conclude that using the approach of steepest slope analysis offers a superior method to correlate in vitro with in vivo results of NP toxicity and for ranking their toxic potency. PMID:22487507

  9. Relevant insight of surface characterization techniques to study covalent grafting of a biopolymer to titanium implant and its acidic resistance

    NASA Astrophysics Data System (ADS)

    D'Almeida, Mélanie; Amalric, Julien; Brunon, Céline; Grosgogeat, Brigitte; Toury, Bérangère

    2015-02-01

    Peri-implant bacterial infections are the main cause of complications in dentistry. Our group has previously proposed the attachment of chitosan on titanium implants via a covalent bond to improve its antibacterial properties while maintaining its biocompatibility. A better knowledge of the coating preparation process allows a better understanding of the bioactive coating in biological conditions. In this work, several relevant characterization techniques were used to assess an implant device during its production phase and its resistance in natural media at different pH. The titanium surface was functionalized with 3-aminopropyltriethoxysilane (APTES) followed by grafting of an organic coupling agent; succinic anhydride, able to form two covalent links, with the substrate through a Ti-O-Si bond and the biopolymer through a peptide bond. Each step of the coating synthesis as well as the presence confirmation of the biopolymer on titanium after saliva immersion was followed by FTIR-ATR, SEM, EDS, 3D profilometry, XPS and ToF-SIMS analyses. Results allowed to highlight the efficiency of each step of the process, and to propose a mechanism occurring during the chitosan coating degradation in saliva media at pH 5 and at pH 3.

  10. A comparative study of ideal kink stability in two reactor-relevant tokamak plasma configurations with negative and positive triangularity

    NASA Astrophysics Data System (ADS)

    Ren, Jing; Liu, Yueqiang; Liu, Yue; Medvedev, S. Yu; Wang, Zhirui; Xia, Guoliang

    2016-11-01

    The effects of an ideal/resistive conducting wall, the drift kinetic resonances, as well as the toroidal plasma flow, on the stability of the ideal external kink mode are numerically investigated for a reactor-relevant tokamak plasma with strongly negative triangularity (NTR) shaping. Comparison is made for a similar plasma equilibrium, but with positive triangularity (PTR). It is found that the ideal wall stabilization is less efficient for the kink stabilization in the NTR plasma due to a less ‘external’ eigenmode structure compared to the PTR plasma. The associated plasma displacement in the NTR plasma does not ‘balloon’ near the outboard mid-plane, as is normally the case for the pressure-driven kink-ballooning instability in PTR plasmas, but being more pronounced near the X-points. The toroidal flow plays a similar role for the kink stability for both NTR and PTR plasmas. The drift kinetic damping is less efficient for the ideal external kink mode in the NTR plasma, despite a somewhat larger fraction of the particle trapping near the plasma edge compared to the PTR equilibrium. However, the drift kinetic damping of the resistive wall mode (RWM) in the NTR plasma is generally as efficient as that of the PTR plasma, although the RWM window, in terms of the normalized pressure, is narrower for the NTR plasma.

  11. A digital process for additive manufacturing of occlusal splints: a clinical pilot study

    PubMed Central

    Salmi, Mika; Paloheimo, Kaija-Stiina; Tuomi, Jukka; Ingman, Tuula; Mäkitie, Antti

    2013-01-01

    The aim of this study was to develop and evaluate a digital process for manufacturing of occlusal splints. An alginate impression was taken from the upper and lower jaws of a patient with temporomandibular disorder owing to cross bite and wear of the teeth, and then digitized using a table laser scanner. The scanned model was repaired using the 3Data Expert software, and a splint was designed with the Viscam RP software. A splint was manufactured from a biocompatible liquid photopolymer by stereolithography. The system employed in the process was SLA 350. The splint was worn nightly for six months. The patient adapted to the splint well and found it comfortable to use. The splint relieved tension in the patient's bite muscles. No sign of tooth wear or significant splint wear was detected after six months of testing. Modern digital technology enables us to manufacture clinically functional occlusal splints, which might reduce costs, dental technician working time and chair-side time. Maximum-dimensional errors of approximately 1 mm were found at thin walls and sharp corners of the splint when compared with the digital model. PMID:23614943

  12. Relevance Is the Issue.

    ERIC Educational Resources Information Center

    Smeltzer, Larry

    1993-01-01

    Points out that good research must be applied, theoretical, rigorous, and relevant all at the same time. Argues for relevant research that develops and tests theoretical constructs that provide useful business knowledge. (SR)

  13. A Comparative Kirkwood-Buff Study of Aqueous Methanol Solutions Modeled by the CHARMM Additive and Drude Polarizable Force Fields

    PubMed Central

    Lin, Bin; He, Xibing; MacKerell, Alexander D.

    2013-01-01

    A comparative study on aqueous methanol solutions modeled by the CHARMM additive and Drude polarizable force fields was carried out by employing Kirkwood-Buff analysis. It was shown that both models reproduced the experimental Kirkwood-Buff integrals and excess coordination numbers adequately well over the entire concentration range. The Drude model showed significant improvement over the additive model in solution densities, partial molar volumes, excess molar volumes, concentration-dependent diffusion constants, and dielectric constants. However, the additive model performed somewhat better than the Drude model in reproducing the activity derivative, excess molar Gibbs energy and excess molar enthalpy of mixing. This is due to the additive achieving a better balance among solute-solute, solute-solvent, and solvent-solvent interactions, indicating the potential for improvements in the Drude polarizable alcohol model. PMID:23947568

  14. Blood pressure goal achievement with olmesartan medoxomil-based treatment: additional analysis of the OLMEBEST study

    PubMed Central

    Barrios, Vivencio; Escobar, Carlos; Calderon, Alberto; Böhm, Michael

    2009-01-01

    Aims Guidelines recommend blood pressure (BP) in hypertensive patients should be <140 systolic BP (SBP) and <90 diastolic BP (DBP) mmHg. This analysis assessed goal rate achievement in hypertensive patients receiving olmesartan-based treatment in the OLMEBEST study. Methods Patients with essential hypertension (DBP ≥ 90 mmHg and <110 mmHg) received open-label olmesartan medoxomil 20 mg/day (n = 2306). After 8 weeks, patients with DBP ≥ 90 mmHg (n = 627) were randomized to 4 weeks’ double-blind treatment with olmesartan 40 mg/day monotherapy or olmesartan 20 mg/day plus hydrochlorothiazide (HCTZ) 12.5 mg/day. For this analysis, the numbers and proportions of patients who achieved SBP < 140 mmHg and/or DBP < 90 mmHg at the end of the 4 weeks were calculated. Results In patients who achieved DBP normalization (<90 mmHg) at week 8 (n = 1546) and continued open-label olmesartan 20 mg/day, 66.7% achieved SBP/DBP < 140/90 mmHg at Week 12. In patients who did not achieve DBP normalization at Week 8, 26.8% of those randomized to olmesartan 40 mg/day and 42.5% of those randomized to olmesartan 20 mg/day plus HCTZ 12.5 mg/day achieved a SBP/DBP < 140/90 mmHg at Week 12. Conclusion Olmesartan 40 mg/day and olmesartan 20 mg/day plus HCTZ 12.5 mg/day allow substantial proportions of patients to achieve BP goals. PMID:19756164

  15. Additional erythrocytic and reticulocytic parameters helpful for diagnosis of hereditary spherocytosis: results of a multicentre study.

    PubMed

    Mullier, François; Lainey, Elodie; Fenneteau, Odile; Da Costa, Lydie; Schillinger, Françoise; Bailly, Nicolas; Cornet, Yvan; Chatelain, Christian; Dogne, Jean-Michel; Chatelain, Bernard

    2011-07-01

    Hereditary spherocytosis (HS) is characterised by weakened vertical linkages between the membrane skeleton and the red blood cell's lipid bilayer, leading to the release of microparticles. All the reference tests suffer from specific limitations. The aim of this study was to develop easy to use diagnostic tool for screening of hereditary spherocytosis based on routinely acquired haematological parameters like percentage of microcytes, percentage of hypochromic cells, reticulocyte counts, and percentage of immature reticulocytes. The levels of haemoglobin, mean cell volume, mean corpuscular haemoglobin concentration, reticulocytes (Ret), immature reticulocytes fraction (IRF), hypochromic erythrocytes (Hypo-He) and microcytic erythrocytes (MicroR) were determined on EDTA samples on Sysmex instruments from a cohort of 45 confirmed SH. The HS group was then compared with haemolytical disorders, microcytic anaemia, healthy individuals and routine samples (n = 1,488). HS is characterised by a high Ret count without an equally elevated IRF. All 45 HS have Ret >80,000/μl and Ret(10(9)/L)/IRF (%) greater than 7.7 (rule 1). Trait and mild HS had a Ret/IRF ratio greater than 19. Moderate and severe HS had increased MicroR and MicroR/Hypo-He (rule 2). Combination of both rules gave predictive positive value and negative predictive value of respectively 75% and 100% (n=1,488), which is much greater than single parameters or existing rules. This simple and fast diagnostic method could be used as an excellent screening tool for HS. It is also valid for mild HS, neonates and ABO incompatibilities and overcomes the lack of sensitivity of electrophoresis in ankyrin deficiencies.

  16. Outside enclosure and additional enrichment for dairy goats – a preliminary study

    PubMed Central

    2012-01-01

    Background Dairy goats are commonly housed at a space allowance of 0.7 – 0.8 m2/goat in commercial Norwegian goat herds, which is very low compared to regulations and recommendations in other European countries. One easy and cheap way to increase space allowance is to allow the animals’ access to outdoor area. The aim of this study was to investigate the effect of access to an outside enclosure and environmental enrichment for dairy goats kept in slatted floor pens with low space allowance on their activity pattern and social behaviour. Methods A group of 82 dairy goats on a commercial Norwegian dairy farm were kept inside during the winter period from October to April. In April the goats were given access to an outside enclosure for 8 hours per day. After having access to the enclosure for another for two days, enrichment (branches) was provided, and after 19 days the enrichment were removed. The goats were observed for 5 hours per day for the two last days before they got access to the outside enclosure, the two days in the enclosure, the two first and the two last days with enrichment and for the following two days without enrichment by two trained observers. Results When allowed access to the enclosure, the goats spent nearly 50% of the time outside, and later the time spent outside was reduced to less than 40% (P < 0.0001), but there was no clear effect of enrichment. All the goats appeared to have a regular use of the enclosure. Time spent resting decreased 59.2% to only 25.2% when the goats first got access to the enclosure, but then started to increase again (P < 0.0001). Initially time spent exploring and chewing the branches was 20%, but this was reduced to around 12% in the last part of the ENRICH period (P < 0.0001). Number of aggressive interactions tended to increase when the goats were allowed access to the outdoor enclosure whereas play behaviour was only observed in the outside enclosure (P < 0.05). Conclusions In conclusion

  17. Predictors of healthcare professionals’ attitudes towards family involvement in safety-relevant behaviours: a cross-sectional factorial survey study

    PubMed Central

    Davis, Rachel; Savvopoulou, M; Shergill, R; Shergill, S; Schwappach, D

    2014-01-01

    Objectives To investigate predictors of healthcare professionals’ (HCPs) attitudes towards family involvement in safety-relevant behaviours. Design A cross-sectional fractional factorial survey that assessed HCPs’ attitudes towards family involvement in two error scenarios relating to hand hygiene and medication safety. Each survey comprised two randomised vignettes that described the potential error, how the family member communicated with the HCP about the error and how the HCP responded to the family member’s question. Setting 5 teaching hospitals in London, the Midlands and York. HCPs were approached on a range of medical and surgical wards. Participants 160 HCPs (73 doctors; 87 nurses) aged between 21 and 65 years (mean 37) 102 were female. Outcome measures HCP approval of family member’s behaviour; HCP reaction to the family member; anticipated effects on the family member–HCP relationship; HCP support for being questioned about hand hygiene/medication; affective rating responses. Results HCPs supported family member's intervening (88%) but only 41% agreed this would have positive effects on the family member/HCP relationship. Across vignettes and error scenarios the strongest predictors of attitudes were how the HCP (in the scenario) responded to the family member and whether an error actually occurred. Doctors (vs nurses) provided systematically more positive affective ratings to the vignettes. Conclusions Important predictors of HCPs’ attitudes towards family members’ involvement in patient safety have been highlighted. In particular, a discouraging response from HCP’s decreased support for family members being involved and had strong perceived negative effects on the family member/HCP relationship. PMID:25186154

  18. [Observational studies in the era of evidence based medicine: short review on their relevance, taxonomy and designs].

    PubMed

    Fronteira, Ines

    2013-01-01

    In this review of the literature, we distinguish between experimental and observational studies, highlighting the importance that the later have gained in the era of evidence-based medicine. We further analyze the value of observational studies in light of experimental studies. We present a taxonomy for observational studies based on units of observation and measurement (cross-sectional or longitudinal). We distinguish between descriptive studies and analytical studies. Then, and given its specificity, we define and present a classification for ecological studies. We define and consider the advantages and disadvantages of cross-sectional, case control and cohort studies. We analyze the strength of the evidence given by each study design. We finished by examining what should guide the choice of a study design.

  19. Food additives

    MedlinePlus

    ... or natural. Natural food additives include: Herbs or spices to add flavor to foods Vinegar for pickling ... Certain colors improve the appearance of foods. Many spices, as well as natural and man-made flavors, ...

  20. STUDY OF THE EFFECT OF CHLORINE ADDITION ON MERCURY OXIDATION BY SCR CATALYST UNDER SIMULATED SUBBITUMINOUS COAL FLUE GAS

    EPA Science Inventory

    An entrained flow reactor is used to study the effect of addition of chlorine-containing species on the oxidation of elemental mercury (Hgo)by a selective catalytic reduction (SCR) catalyst in simulated subbituminous coal combustion flue gas. The combustion flue gas was doped wit...

  1. Effect of Additives on Green Sand Molding Properties using Design of Experiments and Taguchi's Quality Loss Function - An Experimental Study

    NASA Astrophysics Data System (ADS)

    Desai, Bhagyashree; Mokashi, Pavani; Anand, R. L.; Burli, S. B.; Khandal, S. V.

    2016-09-01

    The experimental study aims to underseek the effect of various additives on the green sand molding properties as a particular combination of additives could yield desired sand properties. The input parameters (factors) selected were water and powder (Fly ash, Coconut shell and Tamarind) in three levels. Experiments were planned using design of experiments (DOE). On the basis of plans, experiments were conducted to understand the behavior of sand mould properties such as compression strength, shear strength, permeability number with various additives. From the experimental results it could be concluded that the factors have significant effect on the sand properties as P-value found to be less than 0.05 for all the cases studied. The optimization based on quality loss function was also performed. The study revealed that the quality loss associated with the tamarind powder was lesser compared to other additives selected for the study. The optimization based on quality loss function and the parametric analysis using ANOVA suggested that the tamarind powder of 8 gm per Kg of molding sand and moisture content of 7% yield better properties to obtain sound castings.

  2. A Pilot Study to Examine the Effect of Additional Structured Outdoor Playtime on Preschoolers' Physical Activity Levels

    ERIC Educational Resources Information Center

    Alhassan, Sofiya; Nwaokelemeh, Ogechi; Lyden, Kate; Goldsby, TaShauna; Mendoza, Albert

    2013-01-01

    The impact of additional structured outdoor playtime on preschoolers'; physical activity (PA) level is unclear. The purpose of this pilot study was to explore the effects of increasing structured outdoor playtime on preschoolers'; PA levels. Eight full-day classrooms (n = 134 children) from two preschool programmes were randomised into a treatment…

  3. Identification of aspects of functioning, disability and health relevant to patients experiencing vertigo: a qualitative study using the international classification of functioning, disability and health

    PubMed Central

    2012-01-01

    Purpose Aims of this study were to identify aspects of functioning and health relevant to patients with vertigo expressed by ICF categories and to explore the potential of the ICF to describe the patient perspective in vertigo. Methods We conducted a series of qualitative semi-structured face-to-face interviews using a descriptive approach. Data was analyzed using the meaning condensation procedure and then linked to categories of the International Classification of Functioning, Disability and Health (ICF). Results From May to July 2010 12 interviews were carried out until saturation was reached. Four hundred and seventy-one single concepts were extracted which were linked to 142 different ICF categories. 40 of those belonged to the component body functions, 62 to the component activity and participation, and 40 to the component environmental factors. Besides the most prominent aspect “dizziness” most participants reported problems within “Emotional functions (b152), problems related to mobility and carrying out the daily routine. Almost all participants reported “Immediate family (e310)” as a relevant modifying environmental factor. Conclusions From the patients’ perspective, vertigo has impact on multifaceted aspects of functioning and disability, mainly body functions and activities and participation. Modifying contextual factors have to be taken into account to cover the complex interaction between the health condition of vertigo on the individuals’ daily life. The results of this study will contribute to developing standards for the measurement of functioning, disability and health relevant for patients suffering from vertigo. PMID:22738067

  4. Laboratory studies of the low-temperature deliquescence of calcium chloride salts: Relevance to aqueous solutions on Mars and in the Antarctic Dry Valleys

    NASA Astrophysics Data System (ADS)

    Gough, R. V.; Chevrier, V.; Tolbert, M. A.

    2013-12-01

    There is significant interest in the possible existence of liquid water on current Mars. This water would likely exist as a brine in order to be stable on Mars today. It has been proposed that soil salts could form aqueous solutions through either the melting of ice by low-eutectic salts, or by the deliquescence of hygroscopic salts present in the Martian soil. The focus thus far has largely been on perchlorate species, which can melt ice at temperatures as low as 206 K and can deliquesce at relative humidity values as low as 38% RH. A Mars-relevant salt that has been neglected thus far is calcium chloride (CaCl2). Calcium has been reported to be an abundant cation at the Phoenix landing site and Mars Science Laboratory instruments have recently identified calcium as well. Simulations suggest subsurface CaCl2 is an ideal candidate to produce brines with seasonality consistent with observed recurring slope lineae (RSL) (Chevrier et al., 2012). Finally, the only terrestrial site where RSL-like features have been observed (near Don Juan Pond in the Antarctic Dry Valleys) contains abundant CaCl2. These seasonal slope streaks are thought to form when CaCl2 in the soil deliquesces due to contact with atmospheric water vapor (Dickson et al., 2013). It is important to understand how this CaCl2 interacts with water vapor at low temperatures relevant to Mars and the Martian analog sites. Here we use a Raman microscope and environmental cell to monitor the low-temperature (223 - 273 K) deliquescence (solid to aqueous phase transition) and efflorescence (aqueous to solid phase transition) of three hydration states of CaCl2 (dihydrate, tetrahydrate, hexahydrate). We have found that the deliquescence relative humidity (DRH) increases with increasing hydration state, which is an expected result. Average DRH values over the temperature range studied are 20.0 × 2.6% RH for the dihydrate, 31.8 × 6.3% RH for the tetrahydrate and 60.7 × 1.6% RH for the hexahydrate. Once the aqueous

  5. Multi-spectroscopic and molecular modeling studies of bovine serum albumin interaction with sodium acetate food additive.

    PubMed

    Mohammadzadeh-Aghdash, Hossein; Ezzati Nazhad Dolatabadi, Jafar; Dehghan, Parvin; Panahi-Azar, Vahid; Barzegar, Abolfazl

    2017-08-01

    Sodium acetate (SA) has been used as a highly effective protectant in food industry and the possible effect of this additive on the binding to albumin should be taken into consideration. Therefore, for the first time, the mechanism of SA interaction with bovine serum albumin (BSA) has been investigated by multi-spectroscopic and molecular modeling methods under physiological conditions. Stern-Volmer fluorescence quenching analysis showed an increase in the fluorescence intensity of BSA upon increasing the amounts of SA. The high affinity of SA to BSA was demonstrated by a binding constant value (1.09×10(3) at 310°K). The thermodynamic parameters indicated that hydrophobic binding plays a main role in the binding of SA to Albumin. Furthermore, the results of UV-vis spectra confirmed the interaction of this additive to BSA. In addition, molecular modeling study demonstrated that A binding sites of BSA play the main role in the interaction with acetate.

  6. Relevance of Library Collections for Graduate Student Research: A Citation Analysis Study of Doctoral Dissertations at Notre Dame

    ERIC Educational Resources Information Center

    Kayongo, Jessica; Helm, Clarence

    2012-01-01

    This study focused on determining the extent to which collections of the Hesburgh Libraries of Notre Dame met the needs of graduate students. This study data (2005-2007) consisted of a citation analysis of 248 dissertations and focused on the following questions: What were the graduate students citing in their dissertations? Did the library own…

  7. Toward Assessing Internet Use in the Social Studies Classroom: Developing an Inventory Based on a Review of Relevant Literature

    ERIC Educational Resources Information Center

    Shiveley, James M.; VanFossen, Phillip J.

    2009-01-01

    Despite the widely-held acknowledgment of the great potential of the Internet for improving social studies instruction, the available research tells us that most social studies teachers who use the Internet in their classroom do so without changing much in their traditional approach to teaching. This article suggests using the NCSS Position…

  8. "It Just Takes so Much Time!" A Study of Teachers' Use of ICT to Convey Relevance of Mathematical Content

    ERIC Educational Resources Information Center

    Prieto-Rodriguez, Elena

    2016-01-01

    This paper reports on a component of a study which aims to determine how ICT, and in particular some of the technology funded as part of Australian government's DER (Digital Education Revolution) program, is used by teachers in the state of New South Wales. The study looks in particular at whether technology is used to incorporate real-world…

  9. A mechanistic study of manganese(iii) acetate-mediated phosphonyl group additions to [60]- and [70]-fullerenes: the oxidative-ion-transfer mechanism vs. free radical addition.

    PubMed

    Tumanskii, Boris L; Sabirov, Denis S; Lyakhovetsky, Yury I

    2016-11-14

    The phosphonylation of C60 with HP(O)(OAlk)2 and Mn(OAc)3·2H2O has been considered to occur via a free radical (FR) path involving intermediate radicals ˙P(O)(OAlk)2. The present study provides evidence in support of another mechanism for the reactions, oxidative-ion-transfer (OIT). The mechanism involves the change of an acetate group in Mn(OAc)3 for the phosphonate group and oxidation of C60 by the Mn(OAc)2P(O)(OAlk)2 formed to a pair: (C60˙(+), Mn(OAc)2P(O)(OAlk)2˙(-)) followed by the transfer of the phosphonate anion to give the monophposphonylfullerenyl radical. It undergoes reversible dimerization. The polyaddition occurs analogously. Moreover, the compounds Mn(OAc)2P(O)(OAlk)2 (Alk = Et and i-Pr) obtained make novel reagents for phosphonylation of fullerenes working by the OIT mechanism. The reactions of C60 in benzene with equimolar amounts of Mn(OAc)2P(O)(OPr-i)2 or Hg[P(O)(OPr-i)2]2 which is known as working by the FR mechanism since it produces radical ˙P(O)(OPr-i)2 under UV-irradiation, furnished the same radical ˙C60P(O)(OPr-i)2. However, at a 20-fold molar excess of the reagent toward C60, a single derivative C60[P(O)(OPr-i)2]4 and a mixture of derivatives bearing between two and eight phosphonyls were obtained in the former and latter cases, respectively. With C70, the change of the mechanism produced a change in the regioselectivity: 5 and 3 isomers of ˙C70P(O)(OPr-i)2 were obtained, respectively. DFT-calculations provided the hyperfine coupling (hfc) constants of the isomers and explained the regioselectivity change.

  10. Unravelling the impact of hydrocarbon structure on the fumarate addition mechanism--a gas-phase ab initio study.

    PubMed

    Bharadwaj, Vivek S; Vyas, Shubham; Villano, Stephanie M; Maupin, C Mark; Dean, Anthony M

    2015-02-14

    The fumarate addition reaction mechanism is central to the anaerobic biodegradation pathway of various hydrocarbons, both aromatic (e.g., toluene, ethyl benzene) and aliphatic (e.g., n-hexane, dodecane). Succinate synthase enzymes, which belong to the glycyl radical enzyme family, are the main facilitators of these biochemical reactions. The overall catalytic mechanism that converts hydrocarbons to a succinate molecule involves three steps: (1) initial H-abstraction from the hydrocarbon by the radical enzyme, (2) addition of the resulting hydrocarbon radical to fumarate, and (3) hydrogen abstraction by the addition product to regenerate the radical enzyme. Since the biodegradation of hydrocarbon fuels via the fumarate addition mechanism is linked to bio-corrosion, an improved understanding of this reaction is imperative to our efforts of predicting the susceptibility of proposed alternative fuels to biodegradation. An improved understanding of the fuel biodegradation process also has the potential to benefit bioremediation. In this study, we consider model aromatic (toluene) and aliphatic (butane) compounds to evaluate the impact of hydrocarbon structure on the energetics and kinetics of the fumarate addition mechanism by means of high level ab initio gas-phase calculations. We predict that the rate of toluene degradation is ∼100 times faster than butane at 298 K, and that the first abstraction step is kinetically significant for both hydrocarbons, which is consistent with deuterium isotope effect studies on toluene degradation. The detailed computations also show that the predicted stereo-chemical preference of the succinate products for both toluene and butane are due to the differences in the radical addition rate constants for the various isomers. The computational and kinetic modeling work presented here demonstrates the importance of considering pre-reaction and product complexes in order to accurately treat gas phase systems that involve intra and inter

  11. Enantioselective conjugate addition of nitro compounds to α,β-unsaturated ketones: an experimental and computational study.

    PubMed

    Manzano, Rubén; Andrés, José M; Álvarez, Rosana; Muruzábal, María D; de Lera, Ángel R; Pedrosa, Rafael

    2011-05-16

    A series of chiral thioureas derived from easily available diamines, prepared from α-amino acids, have been tested as catalysts in the enantioselective Michael additions of nitroalkanes to α,β-unsaturated ketones. The best results are obtained with the bifunctional catalyst prepared from L-valine. This thiourea promotes the reaction with high enantioselectivities and chemical yields for aryl/vinyl ketones, but the enantiomeric ratio for alkyl/vinyl derivatives is very modest. The addition of substituted nitromethanes led to the corresponding adducts with excellent enantioselectivity but very poor diastereoselectivity. Evidence for the isomerization of the addition products has been obtained from the reaction of chalcone with [D(3)]nitromethane, which shows that the final addition products epimerize under the reaction conditions. The epimerization explains the low diastereoselectivity observed in the formation of adducts with two adjacent tertiary stereocenters. Density functional studies of the transition structures corresponding to two alternative activation modes of the nitroalkanes and α,β-unsaturated ketones by the bifunctional organocatalyst have been carried out at the B3LYP/3-21G* level. The computations are consistent with a reaction model involving the Michael addition of the thiourea-activated nitronate to the ketone activated by the protonated amine of the organocatalyst. The enantioselectivities predicted by the computations are consistent with the experimental values obtained for aryl- and alkyl-substituted α,β-unsaturated ketones.

  12. Inelastic neutron scattering studies of Ge-76 and Se-76: relevance to neutrinoless double-beta decay

    SciTech Connect

    Crider, Ben; Peters, Erin; Ross, T.J.; McEllistrem, M; Prados-Estevez, F.; Allmond, James M; Vanhoy, J.R.; Yates, S.W.

    2015-01-01

    Inelastic neutron scattering measurements were performed at the University of Kentucky Accelerator Laboratory on enriched Ge-76 and Se-76 scattering samples. From measurements at incident neutron energies from 2.0 to 4.0 MeV, many new levels were identified and characterized in each nucleus; level lifetimes, transition probabilities, multipole mixing ratios, and other properties were determined. In addition, gamma-ray cross sections for the Ge-76(n,n'gamma) reaction were measured at neutron energies up to 5.0 MeV, with the goal of determining the cross sections of gamma rays in 2040-keV region, which corresponds to the region of interest in the neutrinoless double beta decay of Ge-76. Gamma rays from the three strongest branches from the 3952-keV level were observed, but the previously reported 2041-keV gamma ray was not. Population cross sections across the range of incident neutron energies were determined for the 3952-keV level, resulting in a cross section of similar to 0.1 mb for the 2041-keV branch using the previously determined branching ratios. Beyond this, the data from these experiments indicate that previously unreported gamma rays from levels in Ge-76 can be found in the 2039-keV region.

  13. A study of internal structure in components made by additive manufacturing process using 3 D X-ray tomography

    SciTech Connect

    Raguvarun, K. Balasubramaniam, Krishnan Rajagopal, Prabhu; Palanisamy, Suresh; Nagarajah, Romesh; Kapoor, Ajay; Hoye, Nicholas; Curiri, Dominic

    2015-03-31

    Additive manufacturing methods are gaining increasing popularity for rapidly and efficiently manufacturing parts and components in the industrial context, as well as for domestic applications. However, except when used for prototyping or rapid visualization of components, industries are concerned with the load carrying capacity and strength achievable by additive manufactured parts. In this paper, the wire-arc additive manufacturing (AM) process based on gas tungsten arc welding (GTAW) has been examined for the internal structure and constitution of components generated by the process. High-resolution 3D X-ray tomography is used to gain cut-views through wedge-shaped parts created using this GTAW additive manufacturing process with titanium alloy materials. In this work, two different control conditions for the GTAW process are considered. The studies reveal clusters of porosities, located in periodic spatial intervals along the sample cross-section. Such internal defects can have a detrimental effect on the strength of the resulting AM components, as shown in destructive testing studies. Closer examination of this phenomenon shows that defect clusters are preferentially located at GTAW traversal path intervals. These results highlight the strong need for enhanced control of process parameters in ensuring components with minimal defects and higher strength.

  14. Pharmacogenetic relevance of the CYP2C9*3 allele in a tenoxicam bioequivalence study performed on Spaniards.

    PubMed

    Peiró, A M; Novalbos, J; Zapater, P; Moreu, R; López-Rodríguez, R; Rodríguez, V; Abad-Santos, F; Horga, J F

    2009-01-01

    We performed a study to quantify CYP2C9 and CYP2C8 alleles influence on the variability observed in tenoxicam pharmacokinetic (PK) and implication in a bioequivalence study design performed on Spaniards. Eighteen healthy volunteers were included in an open, randomized, crossover, phase I bioequivalence study. Significant increases were found in CYP2C9*3 alleles vs. *1 and *2 in AUC(0-infinity) (median (min-max)): 256 (230-516) vs. 150 (100-268) and 169 (124-197) microg h/mL (p<0.01) and half-life time (t1/2) 102 (79-36) vs. 56 (45-94) and 64 (60-80)h (p<0.01). Non-significant differences were observed in C(max) 1.9 (1.8-2.9) vs. 2.4 (1.7-3.4), 2.5 (1.6-2.9) microg/mL or in according to CYP2C8 alleles presence. CYP2C9*3 allele is associated to a longer elimination time of tenoxicam. PK parameters calculated in bioequivalence studies (AUC(0-infinity), t1/2) may be influenced by the presence of CYP2C9*3 allele resulting in a high variability. Thus, bioequivalence studies of tenoxicam formulations should be designed considering genotype profile.

  15. Case Studies of Leading Edge Small Urban High Schools. Relevance Strategic Designs: 5. Life Academy of Health and Bioscience

    ERIC Educational Resources Information Center

    Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

    2008-01-01

    This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

  16. The Language Element in the Somerset Mode III Integrated European Studies Syllabus and Its Relevance to the Less Able Pupil

    ERIC Educational Resources Information Center

    King, Barrie

    1974-01-01

    The Somerset CSE Mode III integrated European Studies syllabus, which contains a French language course, is aimed at the lower and below CSE candidate. The second language element of the course is described and reasons for constructing such a course for less able students are discussed. (RM)

  17. Are Apprenticeships Still Relevant in the 21st Century? A Case Study of Changing Youth Training Arrangements in German Banks.

    ERIC Educational Resources Information Center

    Finegold, David; Wagner, Karin

    2002-01-01

    A case study of German banking apprentices found that, if employers are entirely motivated by the logic of consequences (recruitment cost savings, workplace flexibility), the system might be undermined by head hunting for apprentices trained by others. The logic of appropriateness fosters trust among employers and creates mechanisms to keep the…

  18. Feasibility of Providing Culturally Relevant, Brief Interpersonal Psychotherapy for Antenatal Depression in an Obstetrics Clinic: A Pilot Study

    ERIC Educational Resources Information Center

    Grote, Nancy K.; Bledsoe, Sarah E.; Swartz, Holly A.; Frank, Ellen

    2004-01-01

    Objective: To minimize barriers to care, ameliorate antenatal depression, and prevent postpartum depression, we conducted a pilot study to assess the feasibility of providing brief interpersonal psychotherapy (IPT-B) to depressed, pregnant patients on low incomes in an obstetrics and gynecological (OB/GYN) clinic. Method: Twelve pregnant,…

  19. A Policy-Relevant Instrumental Case Study of an Inclusive STEM-Focused High School: Manor New Tech High

    ERIC Educational Resources Information Center

    Lynch, Sharon J.; Spillane, Nancy; House, Ann; Peters-Burton, Erin; Behrend, Tara; Ross, Kathleen M.; Han, Edmund M.

    2017-01-01

    This instrumental case study of Manor New Tech High (MNTH) provides insight and understanding of a trend in U.S. education to create new STEM schools and increase the achievement of students underrepresented in STEM. MNTH was an inclusive, STEM-focused high school, in Manor, Texas. The creation of the school was stimulated by a statewide Texas…

  20. Thiamethoxam induced mouse liver tumors and their relevance to humans. Part 1: mode of action studies in the mouse.

    PubMed

    Green, Trevor; Toghill, Alison; Lee, Robert; Waechter, Felix; Weber, Edgar; Noakes, James

    2005-07-01

    Thiamethoxam, a neonicotinoid insecticide, which is not mutagenic either in vitro or in vivo, caused an increased incidence of liver tumors in mice when fed in the diet for 18 months at concentrations in the range 500 to 2500 ppm. A number of dietary studies of up to 50 weeks duration have been conducted in order to identify the mode of action for the development of the liver tumors seen at the end of the cancer bioassay. Both thiamethoxam and its major metabolites have been tested in these studies. Over the duration of a 50-week thiamethoxam dietary feeding study in mice, the earliest change, within one week, is a marked reduction (by up to 40%) in plasma cholesterol. This was followed 10 weeks later by evidence of liver toxicity including single cell necrosis and an increase in apoptosis. After 20 weeks there was a significant increase in hepatic cell replication rates. All of these changes persisted from the time they were first observed until the end of the study at 50 weeks. They occurred in a dose-dependent manner and were only observed at doses (500, 1250, 2500 ppm) where liver tumors were increased in the cancer bioassay. There was a clear no-effect level of 200 ppm. The changes seen in this study are consistent with the development of liver cancer in mice and form the basis of the mode of action. When the major metabolites of thiamethoxam, CGA322704, CGA265307, and CGA330050 were tested in dietary feeding studies of up to 20 weeks duration, only metabolite CGA330050 induced the same changes as those seen in the liver in the thiamethoxam feeding study. It was concluded that thiamethoxam is hepatotoxic and hepatocarcinogenic as a result of its metabolism to CGA330050. Metabolite CGA265307 was also shown to be an inhibitor of inducible nitric oxide synthase and to increase the hepatotoxicity of carbon tetrachloride. It is proposed that CGA265307, through its effects on nitric oxide synthase, exacerbates the toxicity of CGA330050 in thiamethoxam treated mice.

  1. Potlining Additives

    SciTech Connect

    Rudolf Keller

    2004-08-10

    In this project, a concept to improve the performance of aluminum production cells by introducing potlining additives was examined and tested. Boron oxide was added to cathode blocks, and titanium was dissolved in the metal pool; this resulted in the formation of titanium diboride and caused the molten aluminum to wet the carbonaceous cathode surface. Such wetting reportedly leads to operational improvements and extended cell life. In addition, boron oxide suppresses cyanide formation. This final report presents and discusses the results of this project. Substantial economic benefits for the practical implementation of the technology are projected, especially for modern cells with graphitized blocks. For example, with an energy savings of about 5% and an increase in pot life from 1500 to 2500 days, a cost savings of $ 0.023 per pound of aluminum produced is projected for a 200 kA pot.

  2. Phosphazene additives

    DOEpatents

    Harrup, Mason K; Rollins, Harry W

    2013-11-26

    An additive comprising a phosphazene compound that has at least two reactive functional groups and at least one capping functional group bonded to phosphorus atoms of the phosphazene compound. One of the at least two reactive functional groups is configured to react with cellulose and the other of the at least two reactive functional groups is configured to react with a resin, such as an amine resin of a polycarboxylic acid resin. The at least one capping functional group is selected from the group consisting of a short chain ether group, an alkoxy group, or an aryloxy group. Also disclosed are an additive-resin admixture, a method of treating a wood product, and a wood product.

  3. Statistical studies of Pc 3-5 pulsations and their relevance for possible source mechanisms of ULF waves

    NASA Technical Reports Server (NTRS)

    Anderson, Brian J.

    1993-01-01

    A number of statistical studies using spacecraft data have been made of ULF waves in the magnetosphere. These studies provide an overview of ULF pulsation activity for r = 5-15 R(E) and allow an assessment of likely source mechanisms. In this review pulsations are categorized into five general types: compressional Pc 5, poloidal Pc 4, toroidal harmonics, toroidal Pc 5 (fundamental mode), and incoherent noise. The occurrence distributions and/or distributions of wave power of the different types suggest that compressional Pc 5 and poloidal Pc 4 derive their energy locally, most likely from energetic protons. The toroidal pulsations, both harmonic and fundamental mode, appear to be driven by an energy source outside the magnetopause - directly upstream in the sheath and solar wind for harmonics and the flanks for fundamentals. Incoherent pulsations are a prominent pulsation type but from their occurrence distribution alone it is unclear what their dominant energy source may be.

  4. Unusual Application Of Ion Beam Analysis For The Study Of Surface Layers On Materials Relevant To Cultural Heritage

    SciTech Connect

    Mathis, F.; Salomon, J.; Aucouturier, M.; Trocellier, P.

    2006-12-01

    Recently a new thematic of research -- intentional patinas on antic copper-base objects -- lead the AGLAE (Accelerateur Grand Louvre pour l'Analyse Elementaire) team of the C2RMF (Centre de Recherche et de Restauration des Musees de France) to improve its methods of analyzing thin surface layers both in their elemental composition and in-depth elemental distribution. A new beam extraction set-up containing a particle detector has been developed in order to use a 6 MeV alpha beam both in PIXE and RBS mode and to monitor precisely the ion dose received by the sample. Both RBS and ionization cross sections were assessed in order to make sure that the analysis can be quantitative. This set up allows great progresses in the understanding of both nature and structure of this very particular oxide layer obtained in the antiquity by chemical treatment on copper alloys, containing gold and/or silver and presenting very interesting properties of color and stability.Besides the non destructive properties of the IBA in external beam mode, this method of analyzing allows the study of samples in interaction with its environment. This was used to study the high temperature oxidation of Cu-Sn alloys using a furnace developed in order to heat a sample and analyze it in RBS mode at the same time. This new way of studying the growth of oxide layers permits to understand the oxidation mechanism of this system and to propose an experimental model for the identification of oxide layers due to an exposition to a high temperature, model needed for a long time by curators in charge of the study and the conservation of archaeological bronzes.

  5. Male reproductive system parameters in a two-generation reproduction study of ammonium perfluorooctanoate in rats and human relevance.

    PubMed

    York, Raymond G; Kennedy, Gerald L; Olsen, Geary W; Butenhoff, John L

    2010-04-30

    Ammonium perfluorooctanoate (ammonium PFOA) is an industrial surfactant that has been used primarily as a processing aid in the manufacture of fluoropolymers. The environmental and metabolic stability of PFOA together with its presence in human blood and long elimination half-life have led to extensive toxicological studies in laboratory animals. Two recent publications based on observations from the Danish general population have reported: (1) a negative association between serum concentrations of PFOA in young adult males and their sperm counts and (2) a positive association among women with time to pregnancy. A two-generation reproduction study in rats was previously published (2004) in which no effects on functional reproduction were observed at doses up to 30mg ammonium PFOA/kg body weight. The article contained the simple statement: "In males, fertility was normal as were all sperm parameters". In order to place the recent human epidemiological data in perspective, herein we provide the detailed male reproductive parameters from that study, including sperm quality and testicular histopathology. Sperm parameters in rats from the two-generation study in all ammonium PFOA treatment groups were unaffected by treatment with ammonium PFOA. These observations reflected the normal fertility observations in these males. No evidence of altered testicular and sperm structure and function was observed in ammonium PFOA-treated rats whose mean group serum PFOA concentrations ranged up to approximately 50,000ng/mL. Given that median serum PFOA in the Danish cohorts was approximately 5ng/mL, it seems unlikely that concentrations observed in the general population, including those recently reported in Danish general population, could be associated causally with a real decrement in sperm number and quality.

  6. Characterization of a new chronic lymphocytic leukemia cell line for mechanistic in vitro and in vivo studies relevant to disease.

    PubMed

    Hertlein, Erin; Beckwith, Kyle A; Lozanski, Gerard; Chen, Timothy L; Towns, William H; Johnson, Amy J; Lehman, Amy; Ruppert, Amy S; Bolon, Brad; Andritsos, Leslie; Lozanski, Arletta; Rassenti, Laura; Zhao, Weiqiang; Jarvinen, Tiina M; Senter, Leigha; Croce, Carlo M; Symer, David E; de la Chapelle, Albert; Heerema, Nyla A; Byrd, John C

    2013-01-01

    Studies of chronic lymphocytic leukemia (CLL) have yielded substantial progress, however a lack of immortalized cell lines representative of the primary disease has hampered a full understanding of disease pathogenesis and development of new treatments. Here we describe a novel CLL cell line (OSU-CLL) generated by EBV transformation, which displays a similar cytogenetic and immunophenotype observed in the patient's CLL (CD5 positive with trisomy 12 and 19). A companion cell line was also generated from the same patient (OSU-NB). This cell line lacked typical CLL characteristics, and is likely derived from the patient's normal B cells. In vitro migration assays demonstrated that OSU-CLL exhibits migratory properties similar to primary CLL cells whereas OSU-NB has significantly reduced ability to migrate spontaneously or towards chemokine. Microarray analysis demonstrated distinct gene expression patterns in the two cell lines, including genes on chromosomes 12 and 19, which is consistent with the cytogenetic profile in this cell line. Finally, OSU-CLL was readily transplantable into NOG mice, producing uniform engraftment by three weeks with leukemic cells detectable in the peripheral blood spleen and bone marrow. These studies describe a new CLL cell line that extends currently available models to study gene function in this disease.

  7. Characterization of a New Chronic Lymphocytic Leukemia Cell Line for Mechanistic In Vitro and In Vivo Studies Relevant to Disease

    PubMed Central

    Hertlein, Erin; Beckwith, Kyle A.; Lozanski, Gerard; Chen, Timothy L.; Towns, William H.; Johnson, Amy J.; Lehman, Amy; Ruppert, Amy S.; Bolon, Brad; Andritsos, Leslie; Lozanski, Arletta; Rassenti, Laura; Zhao, Weiqiang; Jarvinen, Tiina M.; Senter, Leigha; Croce, Carlo M.; Symer, David E.; de la Chapelle, Albert; Heerema, Nyla A.; Byrd, John C.

    2013-01-01

    Studies of chronic lymphocytic leukemia (CLL) have yielded substantial progress, however a lack of immortalized cell lines representative of the primary disease has hampered a full understanding of disease pathogenesis and development of new treatments. Here we describe a novel CLL cell line (OSU-CLL) generated by EBV transformation, which displays a similar cytogenetic and immunophenotype observed in the patient’s CLL (CD5 positive with trisomy 12 and 19). A companion cell line was also generated from the same patient (OSU-NB). This cell line lacked typical CLL characteristics, and is likely derived from the patient’s normal B cells. In vitro migration assays demonstrated that OSU-CLL exhibits migratory properties similar to primary CLL cells whereas OSU-NB has significantly reduced ability to migrate spontaneously or towards chemokine. Microarray analysis demonstrated distinct gene expression patterns in the two cell lines, including genes on chromosomes 12 and 19, which is consistent with the cytogenetic profile in this cell line. Finally, OSU-CLL was readily transplantable into NOG mice, producing uniform engraftment by three weeks with leukemic cells detectable in the peripheral blood spleen and bone marrow. These studies describe a new CLL cell line that extends currently available models to study gene function in this disease. PMID:24130782

  8. Assessing environmental impacts of genetically modified plants on non-target organisms: The relevance of in planta studies.

    PubMed

    Arpaia, Salvatore; Birch, A Nicholas E; Kiss, Jozsef; van Loon, Joop J A; Messéan, Antoine; Nuti, Marco; Perry, Joe N; Sweet, Jeremy B; Tebbe, Christoph C

    2017-04-01

    In legal frameworks worldwide, genetically modified plants (GMPs) are subjected to pre-market environmental risk assessment (ERA) with the aim of identifying potential effects on the environment. In the European Union, the EFSA Guidance Document introduces the rationale that GMPs, as well as their newly produced metabolites, represent the potential stressor to be evaluated during ERA. As a consequence, during several phases of ERA for cultivation purposes, it is considered necessary to use whole plants or plant parts in experimental protocols. The importance of in planta studies as a strategy to address impacts of GMPs on non-target organisms is demonstrated, to evaluate both effects due to the intended modification in plant phenotype (e.g. expression of Cry proteins) and effects due to unintended modifications in plant phenotype resulting from the transformation process (e.g. due to somaclonal variations or pleiotropic effects). In planta tests are also necessary for GMPs in which newly expressed metabolites cannot easily be studied in vitro. This paper reviews the scientific literature supporting the choice of in planta studies as a fundamental tool in ERA of GMPs in cultivation dossiers; the evidence indicates they can realistically mimic the ecological relationships occurring in their receiving environments and provide important insights into the biology and sustainable management of GMPs.

  9. Stability of indomethacin with relevance to the release from amorphous solid dispersions studied with ATR-FTIR spectroscopic imaging.

    PubMed

    Ewing, Andrew V; Clarke, Graham S; Kazarian, Sergei G

    2014-08-18

    This work presents the use of attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and spectroscopic imaging to study the stability and dissolution behaviour of amorphous solid dispersions (ASDs). ASDs are employed to improve the bioavailability of drugs which are poorly soluble in aqueous solutions. Selecting the appropriate polymeric excipients for use in pharmaceutical tablets is crucial to control drug stability and subsequent release. In this study, indomethacin was used as a model poorly-aqueous soluble drug since the amorphous-form has improved dissolution properties over its crystalline forms. ASDs of indomethacin/polyethylene glycol (PEG) and indomethacin/hydroxypropyl methylcellulose (HPMC) in a 1:3 wt ratio were compared. Firstly, ATR-FTIR spectroscopy was employed to monitor the stability of indomethacin in the ASDs over 96 h. While the indomethacin/HPMC ASD showed the ability to maintain the amorphous indomethacin form for longer periods of time, ATR-FTIR spectra revealed that indomethacin in the drug/PEG ASD crystallised to the stable γ-form, via the α-form. Secondly, ATR-FTIR spectroscopic imaging was used to study the dissolution of ASD tablets in a phosphate buffer (pH 7.5). Crystallisation of amorphous indomethacin was characterised in the spectra collected during the dissolution of the indomethacin/PEG ASD which consequently hindered release into the surrounding solution. In contrast, release of amorphous indomethacin was more effective from HPMC.

  10. Stratigraphic and sedimetological study of relevant lahar deposits of La Lumbre ravine, Colima volcano (Mexico): preliminary results.

    NASA Astrophysics Data System (ADS)

    Sarocchi, D.; Rodriguez-Sedano, L. A.; Saucedo, R.; Capra, L.

    2009-04-01

    Volcán de Colima is the most active volcano of Mexico with more than fifty eruptions documented in the last four centuries. The great amount of pyroclastic material deposited in the volcano slopes represents a perfect source for an intense lahar activity. Despite the intense volcanic activity with production of explosive eruptions and pyroclastic flows, lahars are greatly the most dangerous phenomena at Volcán de Colima. Pyroclastic flows did not reach long distances, generally less than 5 km from the crater. In contrast, lahars travel long distances, up to 10 km, causing damage to infrastructure and being able to affect populated areas. For this reason in the last 100 years more than 350 people died for lahars in the Colima Volcanic Complex and only 8 lost their lives for pyroclastic flows in 1913 plinian eruption. "La Lumbre" ravine is a very important morphological feature in the western-southwestern sector of the volcano, there, it gathers the main drainage system and collects water from "El Playon", a wide intra-caldera basin delimited by the Volcán de Colima to the south and the "Paleofuego" caldera rim to the north. This ravine produced huge lahars such as the 1906 lahar which killed almost 325 people, or the lahars associated with the great 1913 eruption, other associated with de 1990-91 volcanic crisis, and is still very active, continuously remobilizing the 1998-99 pyroclastic flow deposits. In 2002 near the confluence between "La Lumbre" and "El Zarco" Ravine, a house was destroyed fortunately with no danger for people. In order to perform future accurate lahar numerical simulation and obtain reliable hazard study along this ravine, is very important to reconstruct the complex stratigraphy and understand which of such important deposits is related with the 1906, 1913 or 1991 eruptive crisis. For this reason we are performing a detailed stratigraphic study of the lahars sequence. We selected the best outcrops at different distances from the crater. In

  11. Nurses' decision-making in ethically relevant clinical situations using the example of breathlessness: study protocol of a reflexive grounded theory integrating Goffman's framework analysis

    PubMed Central

    Dunger, Christine; Schnell, Martin W; Bausewein, Claudia

    2017-01-01

    Introduction Decision-making (DM) in healthcare can be understood as an interactive process addressing decision makers' reasoning as well as their visible behaviour after the decision is made. Other key elements of DM are ethical aspects and the role as well as the treatment options of the examined professions. Nurses' DM to choose interventions in situations of severe breathlessness is such interactions. They are also ethically relevant regarding the vulnerability of affected patients and possible restrictions or treatment options. The study aims to explore which factors influence nurses' DM to use nursing interventions in situations where patients suffer from severe breathlessness. Methods and analysis Qualitative study including nurses in German hospital wards and hospices. A triangulation of different methods of data collection—participant observation and qualitative expert interviews—and analysis merge in a reflexive grounded theory approach which integrates Goffman's framework analysis. It allows an analysis of nurses' self-statements about DM, their behaviour in relevant clinical situations and its influences. Data collection and analysis will be examined simultaneously. Ethics and dissemination Informed consent will be gained from all participants and the institutional stakeholders. Ongoing consent has to be ensured since observations will take place in healthcare institutions and many patients will be highly vulnerable. The study has been evaluated and approved by the Witten/Herdecke University Ethics Committee, Witten, Germany. Results of the study will be published at congresses and in journal papers.

  12. Valerian: No Evidence for Clinically Relevant Interactions

    PubMed Central

    Nieber, Karen; Kraft, Karin

    2014-01-01

    In recent popular publications as well as in widely used information websites directed to cancer patients, valerian is claimed to have a potential of adverse interactions with anticancer drugs. This questions its use as a safe replacement for, for example, benzodiazepines. A review on the interaction potential of preparations from valerian root (Valeriana officinalis L. root) was therefore conducted. A data base search and search in a clinical drug interaction data base were conducted. Thereafter, a systematic assessment of publications was performed. Seven in vitro studies on six CYP 450 isoenzymes, on p-glycoprotein, and on two UGT isoenzymes were identified. However, the methodological assessment of these studies did not support their suitability for the prediction of clinically relevant interactions. In addition, clinical studies on various valerian preparations did not reveal any relevant interaction potential concerning CYP 1A2, 2D6, 2E1, and 3A4. Available animal and human pharmacodynamic studies did not verify any interaction potential. The interaction potential of valerian preparations therefore seems to be low and thereby without clinical relevance. We conclude that there is no specific evidence questioning their safety, also in cancer patients. PMID:25093031

  13. Microstructural Development and Technical Challenges in Laser Additive Manufacturing: Case Study with a 316L Industrial Part

    NASA Astrophysics Data System (ADS)

    Marya, Manuel; Singh, Virendra; Marya, Surendar; Hascoet, Jean Yves

    2015-08-01

    Additive manufacturing (AM) brings disruptive changes to the ways parts, and products are designed, fabricated, tested, qualified, inspected, marketed, and sold. These changes introduce novel technical challenges and concerns arising from the maturity and diversity of today's AM processes, feedstock materials, and process parameter interactions. AM bears a resemblance with laser and electron beam welding in the so-called conduction mode, which involves a multitude of dynamic physical events between the projected feedstock and a moving heat source that eventually influence AM part properties. For this paper, an air vent was selected for its thin-walled, hollow, and variable cross section, and limited size. The studied air vents, randomly selected from a qualification batch, were fabricated out of 316L stainless steel using a 4 kW fiber laser powder-fed AM system, referred to as construction laser additive direct (CLAD). These were systematically characterized by microhardness indentation, visual examination, optical and scanning electron microscopy, and electron-back-scattering diffraction in order to determine AM part suitability for service and also broadly discuss metallurgical phenomena. The paper then briefly expands the discussion to include additional engineering alloys and further analyze relationships between AM process parameters and AM part properties, consistently utilizing past experience with the same powder-fed CLAD 3D printer, the well-established science and technology of welding and joining, and recent publications on additive manufacturing.

  14. Identification of clusters of individuals relevant to temporomandibular disorders and other chronic pain conditions: the OPPERA study.

    PubMed

    Bair, Eric; Gaynor, Sheila; Slade, Gary D; Ohrbach, Richard; Fillingim, Roger B; Greenspan, Joel D; Dubner, Ronald; Smith, Shad B; Diatchenko, Luda; Maixner, William

    2016-06-01

    The classification of most chronic pain disorders gives emphasis to anatomical location of the pain to distinguish one disorder from the other (eg, back pain vs temporomandibular disorder [TMD]) or to define subtypes (eg, TMD myalgia vs arthralgia). However, anatomical criteria overlook etiology, potentially hampering treatment decisions. This study identified clusters of individuals using a comprehensive array of biopsychosocial measures. Data were collected from a case-control study of 1031 chronic TMD cases and 3247 TMD-free controls. Three subgroups were identified using supervised cluster analysis (referred to as the adaptive, pain-sensitive, and global symptoms clusters). Compared with the adaptive cluster, participants in the pain-sensitive cluster showed heightened sensitivity to experimental pain, and participants in the global symptoms cluster showed both greater pain sensitivity and greater psychological distress. Cluster membership was strongly associated with chronic TMD: 91.5% of TMD cases belonged to the pain-sensitive and global symptoms clusters, whereas 41.2% of controls belonged to the adaptive cluster. Temporomandibular disorder cases in the pain-sensitive and global symptoms clusters also showed greater pain intensity, jaw functional limitation, and more comorbid pain conditions. Similar results were obtained when the same methodology was applied to a smaller case-control study consisting of 199 chronic TMD cases and 201 TMD-free controls. During a median 3-year follow-up period of TMD-free individuals, participants in the global symptoms cluster had greater risk of developing first-onset TMD (hazard ratio = 2.8) compared with participants in the other 2 clusters. Cross-cohort predictive modeling was used to demonstrate the reliability of the clusters.

  15. Systemic markers of the redox balance and apolipoprotein E polymorphism in atherosclerosis: the relevance for an integrated study.

    PubMed

    Lopes, Paula A; Napoleão, Patrícia; Pinheiro, Teresa; Ceia, Fátima; Steghens, Jean-Paul; Pavão, M Leoner; Santos, M Cristina; Viegas-Crespo, Ana M

    2006-07-01

    Prospective studies have demonstrated that an imbalance between oxidative damage and antioxidative protection can play a role in the development and progression of atherosclerosis. Also, genotypes with the apolipoprotein E epsilon4 allele have been associated with an increase risk for this pathology. Based on this knowledge, the aim of this study was to evaluate indicators of the redox balance, trace elements, and apolipoprotein E allelic profile in subjects from the Lisbon population with clinically stable atherosclerosis, at risk for atherosclerotic events, and in healthy subjects for comparison. The activities of superoxide dismutase in erythrocytes and glutathione peroxidase in whole blood, plasma total thiols, and serum ceruloplasmin were kept unchanged among the three groups. Serum alpha- tocopherol was increased in atherosclerotic patients. Total malondialdehyde in serum and protein carbonyls in plasma, which are indicators of lipid and protein oxidative damage, respectively, reached their highest values in risk subjects. The concentrations of potassium and calcium, in plasma and in blood cells, were slightly elevated in patients and might reflect an electrolytic imbalance. Regarding the apolipoprotein E polymorphism, atherosclerotic patients had an increased incidence of the high-risk genotypes for atherogenesis (epsilon3/epsilon4 and epsilon4/epsilon4). A multivariate model applied to the general population using most of the parameters clearly separated the three groups at study (i.e., the healthy group from the steady-state group of risk disease and from the atherosclerotic one). As shown by us, the usefulness of biochemical and complementary genetic markers is warranted for a better knowledge on atherosclerosis molecular basis.

  16. Prevalence of Depression in Medical Students at the Lebanese University and Exploring its Correlation With Facebook Relevance: A Questionnaire Study

    PubMed Central

    Haddad, Ramzi S

    2016-01-01

    Background The prevalence of major depression is particularly high in medical students, affecting around one-third of this population. Moreover, online social media, in particular Facebook, is becoming an intrinsic part in the life of a growing proportion of individuals worldwide. Objective Our primary objective is to identify the prevalence of depression in medical students at the Lebanese University Faculty of Medicine, a unique state university in Lebanon, its correlation with the utilization of the interactive features of Facebook, and the way students may resort to these features. Methods Students of the Lebanese University Faculty of Medicine were assessed for (1) depression and (2) Facebook activity. To screen for major depression, we used the Patient Health Questionnaire-9 (PHQ-9) scale. To test for Facebook activity, we developed the Facebook Resorting Questionnaire (FbRQ), which measures the degree to which students resort to Facebook. Results A total of 365 out of 480 students (76.0%) participated in the survey. A total of 25 students were excluded, hence 340 students were included in the final analysis. Current depression was reported in 117 students out of 340 (34.4%) and t tests showed female predominance. Moreover, PHQ-9 score multiple regression analysis showed that feeling depressed is explained 63.5% of the time by specific independent variables studied from the PHQ-9 and the FbRQ. Depression varied significantly among the different academic years (P<.001) and it peaked in the third-year students. One-way analysis of variance (ANOVA) showed that depression and resorting to Facebook had a positive and significant relationship (P=.003) and the different FbRQ categories had significant differences in resorting-to-Facebook power. The like, add friend, and check-in features students used when resorting to Facebook were significantly associated with depression. Conclusions This study showed that depression was highly prevalent among students of the

  17. Case studies of geophysical search methods relevant to the continuation phase of an on-Site inspection

    SciTech Connect

    Sweeney, J J

    1999-04-20

    Part II of the Protocol of the Comprehensive Test Ban Treaty prescribes the use of geophysical methods such as active seismic surveys and electrical conductivity measurements to search for and locate underground anomalies, including cavities and rubble zones, during the continuation phase of an on-site inspection. In this paper the application of spontaneous potential, magnetotelluric, active seismic, and gas sampling studies at the US Nevada Test Site associated with underground nuclear explosions will be described and discussed in the context of on-site inspections. Spontaneous potential and E-field ratio telluric methods were found to be effective in some geologic settings but not in others. An example of gas sampling is shown for which radiogenic gas was detected several years after detonation. The case study of the application of active seismic methods illustrates limitations imposed by the use of relatively simple systems in the field. Detection of a deeply-buried cavity or rubble zone will be difficult; results from the application of only a single method will likely be ambiguous. Best results will come from the synthesis of results from a number of widely-varying methods.

  18. Assessment of quality and relevance of curricula development in health training institutions: a case study of Kenya.

    PubMed

    Mumbo, Hazel M; Kinaro, Joyce W

    2015-08-13

    The World Health Organization lists Kenya among African countries experiencing health workforce crisis catalysed through immigration, underproduction, inconsistent quality of production and unequal distribution. Strengthening health training institutions to increase production of high-quality health workers is acknowledged as a measure to mitigate the crisis.IntraHealth International's USAID-funded FUNZOKenya Project (2012-2017) undertook an assessment to identify the bottlenecks to increasing the number and quality of pre-service graduates in Kenya. The assessment, a cross-sectional descriptive study, collected data through structured respondent interviews among faculty, students in health training institutions, key informants and desk review. The assessment purposively selected 14 institutions from 18 institutions identified for initial collaboration with the project towards strengthening health workforce training. The statistical package for social sciences (SPSS) application helped analyse quantitative data and quotes used to illustrate perceptions on the quality of curricula.The findings revealed major gaps in quality and adequacy of curricula in the training institutions. A national standard framework to guide curricula review process is lacking. Further, curricula did not adequately prepare students for clinical placement, as most failed to directly respond to national health needs. The study recommended reviews of curricula to ensure their responsiveness to emerging issues in the health sector, the formation of curriculum committees to review curricula, development of official curricula review standards and an integrated mechanism to disseminate policies and guidelines.

  19. Network structures and their relevance to the policy cycle: a case study of The National Male Health Policy of Australia.

    PubMed

    Holden, Carol A; Lin, Vivian

    2012-01-01

    While focussing on influential actors within a policy network may provide insight into the shaping of policy, it fails to elucidate how the network itself may moderate the behaviours of actors when participating in the policy process. Applying Skok's (1995) structural-functional framework, this study explores whether network analysis provides an alternative analytical approach to explain how the broader structural features of the network may influence actors participating in different functional phases of the policy cycle. To illustrate the rationale for a network analysis approach to policy analysis, we introduce the 2010 Australian National Male Health Policy, as an illustrative case of a network of competing interests within the broader health policy domain. An analysis of the associated men's health network and the network structures that exist for different relational purposes identified a weak (low density) network, which lacked a hierarchical structure, and where levels of reciprocity between actors was low. Network characteristics changed depending on the relationship type between actors, highlighting the dynamic nature of networks and reflecting the different imperatives of the policy process. An understanding of network structures gained from the network analysis approach described in this study potentially provides policy-makers, and stakeholders, with an alternative tool to stakeholder analysis when considering engagement with the policy process.

  20. The Relevance of the Use of Radiographic Planning in Order to Avoid Complications in Mandibular Implantology: A Retrospective Study

    PubMed Central

    Sammartino, Gilberto; Prados-Frutos, Juan Carlos; Riccitiello, Francesco; Felice, Pietro; Cerone, Vincenzo; Gasparro, Roberta; Wang, Hom-Lay

    2016-01-01

    The aim of this retrospective radiological study was to evaluate the variability of the mandibular anatomy in the presence and absence of teeth and to consider how it could influence implant planning. 187 mandibular CT DentaScans were selected from our department archive according to the inclusion criteria. The axial height, vertical height, angulation of the bone crest, and the bone available for ideal implant placement were measured. The analysis of the data shows that the mandible contour presents a constant degree of angulation. The variation of angulation in the absence of teeth was statistically significant only in the region between the canine and the first premolar and in that between the second premolar and the first molar. The difference between the crest height and the available distance to place the implant was greater in the region of the second molar while in the other regions the implant planning was made complex by postextraction resorption. Alveolar bone resorption after tooth loss can be considered as a risk factor for lingual cortical perforation during the insertion of an implant. To avoid potential intra/postoperative complications, 3D radiographic examination is recommended in order to study the mandibular anatomy and identify the risk areas. PMID:27294136

  1. Mammography usage with relevant factors among women with mental disabilities in Taiwan: a nationwide population-based study.

    PubMed

    Yen, Suh-May; Kung, Pei-Tseng; Tsai, Wen-Chen

    2015-02-01

    Women with mental illness are at increased risk of developing and dying from breast cancer and are thus in urgent need of breast cancer preventive care. This study examined the use of screening mammography by Taiwanese women with mental disabilities and analyzed factors affecting this use. 17,243 Taiwanese women with mental disabilities aged 50-69 years were retrospectively included as study subjects. Linked patient data were obtained from three national databases in Taiwan (the 2008 database of physically and mentally disabled persons, the Health Promotion Administration's 2007-2008 mammography screening data, and claims data from the National Health Insurance Research Database). Besides descriptive statistics and bivariate analysis, logistic regression analysis was also performed to examine factors affecting screening mammography use. The 2007-2008 mammography screening rate for Taiwanese women with mental disabilities was 8.79% (n=1515). Variables that significantly influenced screening use were income, education, presence of catastrophic illness/injury, severity of mental disability, and usage of other preventive care services. Screening was positively correlated with income and education. Those with catastrophic illness/injury were more likely to be screened (odds ratio [OR], 1.40; 95% CI=1.15-1.72). Severity of disability was negatively correlated with screening, with very severe, severe, and moderate disability being associated with 0.34-0.69 times the odds of screening as mild disability. In Taiwan, women with mental disabilities receive far less mammography screening than women in general.

  2. Making Science Relevant

    ERIC Educational Resources Information Center

    Eick, Charles; Deutsch, Bill; Fuller, Jennifer; Scott, Fletcher

    2008-01-01

    Science teachers are always looking for ways to demonstrate the relevance of science to students. By connecting science learning to important societal issues, teachers can motivate students to both enjoy and engage in relevant science (Bennet, Lubben, and Hogarth 2007). To develop that connection, teachers can help students take an active role in…

  3. New concepts of science and medicine in science and technology studies and their relevance to science education.

    PubMed

    Wang, Hsiu-Yun; Stocker, Joel F; Fu, Daiwie

    2012-02-01

    Science education often adopts a narrow view of science that assumes the lay public is ignorant, which seemingly justifies a science education limited to a promotional narrative of progress in the form of scientific knowledge void of meaningful social context. We propose that to prepare students as future concerned citizens of a technoscientific society, science education should be informed by science, technology, and society (STS) perspectives. An STS-informed science education, in our view, will include the following curricular elements: science controversy education, gender issues, historical perspective, and a move away from a Eurocentric view by looking into the distinctive patterns of other regional (in this case of Taiwan, East Asian) approaches to science, technology, and medicine. This article outlines the significance of some major STS studies as a means of illustrating the ways in which STS perspectives can, if incorporated into science education, enhance our understanding of science and technology and their relationships with society.

  4. Genomics for public health improvement: relevant international ethical and policy issues around genome-wide association studies and biobanks.

    PubMed

    Pang, T

    2013-01-01

    Genome-wide association studies and biobanks are at the forefront of genomics research and possess unprecedented potential to improve public health. However, for public health genomics to ultimately fulfill its potential, technological and scientific advances alone are insufficient. Scientists, ethicists, policy makers, and regulators must work closely together with research participants and communities in order to craft an equitable and just ethical framework, and a sustainable environment for effective policies. Such a framework should be a 'hybrid' form which balances equity and solidarity with entrepreneurship and scientific advances. A good balance between research and policy on one hand, and privacy, protection and trust on the other is the key for public health improvement based on advances in genomics science.

  5. Study of resonant scattering of 21Na+p relevant to astrophysical 18Ne(α,p)21Na reaction

    NASA Astrophysics Data System (ADS)

    He, J. J.; Zhang, L. Y.; Xu, S. W.; Chen, S. Z.; Hu, J.; Ma, P.; Chen, R. F.; Yamaguchi, H.; Kubono, S.; Hashimoto, T.; Kahl, D.; Hayakawa, S.; Wakabayashi, Y.; Togano, Y.; Wang, H. W.; Tian, W. D.; Guo, B.; Teranishi, T.; Iwasa, N.; Yamada, T.; Komatsubara, T.

    2012-11-01

    Astrophysical 18Ne(α,p)21Na reaction is one of the most probable breakout routes, which lead to the rp-process from the hot-CNO cycle, converting the initial CNO elements into heavier elements in Type I x-ray bursters. Presently, there is no much experimental cross-section data reported at the energy of astrophysical interest, and resonant spectroscopic information in compound 22Mg is scarce as well. The experiment has been carried out by using the CNS radioactive ion beam separator (CRIB). Resonant properties in 22Mg have been studied via the resonant elastic scattering of 21Na+p, and cross section of the time-reversal reaction of 21Na(p,α)18Ne been measured simultaneously. A wide excitation energy region up to Ex ~ 9.5 MeV in 22Mg has been scanned with a thick-target method. Some preliminary results will be reported.

  6. Biological Effects of Clinically Relevant CoCr Nanoparticles in the Dura Mater: An Organ Culture Study

    PubMed Central

    Papageorgiou, Iraklis; Abberton, Thomas; Fuller, Martin; Tipper, Joanne L.; Fisher, John; Ingham, Eileen

    2014-01-01

    Medical interventions for the treatment of spinal disc degeneration include total disc replacement and fusion devices. There are, however, concerns regarding the generation of wear particles by these devices, the majority of which are in the nanometre sized range with the potential to cause adverse biological effects in the surrounding tissues. The aims of this study were to develop an organ culture model of the porcine dura mater and to investigate the biological effects of CoCr nanoparticles in this model. A range of histological techniques were used to analyse the structure of the tissue in the organ culture. The biological effects of the CoCr wear particles and the subsequent structural changes were assessed using tissue viability assays, cytokine assays, histology, immunohistochemistry, and TEM imaging. The physiological structure of the dura mater remained unchanged during the seven days of in vitro culture. There was no significant loss of cell viability. After exposure of the organ culture to CoCr nanoparticles, there was significant loosening of the epithelial layer, as well as the underlying collagen matrix. TEM imaging confirmed these structural alterations. These structural alterations were attributed to the production of MMP-1, -3, -9, -13, and TIMP-1. ELISA analysis revealed that there was significant release of cytokines including IL-8, IL-6, TNF-α, ECP and also the matrix protein, tenascin-C. This study suggested that CoCr nanoparticles did not cause cytotoxicity in the dura mater but they caused significant alterations to its structural integrity that could lead to significant secondary effects due to nanoparticle penetration, such as inflammation to the local neural tissue.

  7. St. Lawrence Seaway N.Y. Feasibility Study for Additional Locks and Other Navigation Improvements: Plan of Study. Revision.

    DTIC Science & Technology

    1979-11-01

    throughout has increased. The shift to larger vessels, laker and ocean, has been faster than the rate of growth in tonnage demand for carriage. Various studies...Conditions Navigation Season 15 April to 15 December (1) (Thousands of Short Tons) :Annual * : Rate of * * *: Growth Commodity :: 1980- Group :1980 1990...December (1) (Thousands of Short Tons) * . * *:Annual * * * *: Rate of *: Growth Commodity : *: 1980- Group :1980 :1990 :2000 :2010 :2020 :2030 : 2030

  8. A quantum chemical study of the mechanisms of olefin addition to group 9 transition metal dioxo compounds.

    PubMed

    Ahmed, Issahaku; Tia, Richard; Adei, Evans

    2016-01-01

    triplet PES than on the singlet PES for the formation of similar analogues. There are fewer competitive reaction pathways on the triplet surface than on the singlet PES. Also, cycloadditions that seem impossible on the singlet PES seem possible on the doublet and or triplet PESs, this is the case typically for the Rh and Co complexes, illustrating the importance of multiple spin states in organometallic reactions.Graphical AbstractTable of Contents Synopsis: A study of the mechanism of ethylene addition to MO2(CH2)(CH3)(M=Co,Rh,Ir) shows the reactions of the Co complex have lower activation barriers for the preferred [3+2] and [2+2] addition pathways and fewer side reactions than those of Rh and Ir. Reactions are more feasible and selective on the triplet PES than on the singlet PES. These illustrate the importance of multiple spin states in organometallic reactions and shows catalyst activity and selectivity decreases down the group.

  9. A fundamental study of the oxidation behavior of SI primary reference fuels with propionaldehyde and DTBP as an additive

    NASA Astrophysics Data System (ADS)

    Johnson, Rodney

    In an effort to combine the benefits of SI and CI engines, Homogeneous Charge Compression Ignition (HCCI) engines are being developed. HCCI combustion is achieved by controlling the temperature, pressure, and composition of the fuel and air mixture so that autoignition occurs in proper phasing with the piston motion. This control system is fundamentally more challenging than using a spark plug or fuel injector to determine ignition timing as in SI and CI engines, respectively. As a result, this is a technical barrier that must be overcome to make HCCI engines applicable to a wide range of vehicles and viable for high volume production. One way to tailor the autoignition timing is to use small amounts of ignition enhancing additives. In this study, the effect of the addition of DTBP and propionaldehyde on the autoignition behavior of SI primary reference fuels was investigated. The present work was conducted in a new research facility built around a single cylinder Cooperative Fuels Research (CFR) octane rating engine but modified to run in HCCI mode. It focused on the effect of select oxygenated hydrocarbons on hydrocarbon fuel oxidation, specifically, the primary reference fuels n-heptane and iso-octane. This work was conducted under HCCI operating conditions. Previously, the operating parameters for this engine were validated for stable combustion under a wide range of operating parameters such as engine speeds, equivalence ratios, compression ratios and inlet manifold temperature. The stable operating range under these conditions was recorded and used for the present study. The major focus of this study was to examine the effect of the addition of DTBP or propionaldehyde on the oxidation behavior of SI primary reference fuels. Under every test condition the addition of the additives DTBP and propionaldehyde caused a change in fuel oxidation. DTBP always promoted fuel oxidation while propionaldehyde promoted oxidation for lower octane number fuels and delayed

  10. A VUV photoionization study of the multichannel reaction of phenyl radicals with 1,3-butadiene under combustion relevant conditions.

    PubMed

    Golan, Amir; Ahmed, Musahid; Mebel, Alexander M; Kaiser, Ralf I

    2013-01-07

    We studied the reaction of phenyl radicals (C(6)H(5)) with 1,3-butadiene (H(2)CCHCHCH(2)) exploiting a high temperature chemical reactor under combustion-like conditions (300 Torr, 873 K). The reaction products were probed in a supersonic beam by utilizing VUV radiation from the Advanced Light Source and by recording the experimental PIE curves at mass-to-charge ratios of m/z = 130 (C(10)H(10)(+)), 116 (C(9)H(8)(+)), and 104 (C(8)H(8)(+)). Our data suggest that the atomic hydrogen (H), methyl (CH(3)), and vinyl (C(2)H(3)) losses are open with estimated branching ratios of about 86 ± 4%, 8 ± 2%, and 6 ± 2%, respectively. The isomer distributions were probed further by fitting the experimentally recorded PIE curves with a linear combination of the PIE curves of individual C(10)H(10), C(9)H(8), and C(8)H(8) isomers. These fits indicate the formation of three C(10)H(10) isomers (trans-1,3-butadienylbenzene, 1,4-dihydronaphthalene, 1-methylindene), three C(9)H(8) isomers (indene, phenylallene, 1-phenyl-1-methylacetylene), and a C(8)H(8) isomer (styrene). A comparison with results from recent crossed molecular beam studies of the 1,3-butadiene-phenyl radical reaction and electronic structure calculations suggests that trans-1,3-butadienylbenzene (130 amu), 1,4-dihydronaphthalene (130 amu), and styrene (104 amu) are reaction products formed as a consequence of a bimolecular reaction between the phenyl radical and 1,3-butadiene. 1-Methylindene (130 amu), indene (116 amu), phenylallene (116 amu), and 1-phenyl-1-methylacetylene (116 amu) are synthesized upon reaction of the phenyl radical with three C(4)H(6) isomers: 1,2-butadiene (H(2)CCCH(CH(3))), 1-butyne (HCCC(2)H(5)), and 2-butyne (CH(3)CCCH(3)); these C(4)H(6) isomers can be formed from 1,3-butadiene via hydrogen atom assisted isomerization reactions or via thermal rearrangements of 1,3-butadiene involving hydrogen shifts in the high temperature chemical reactor.

  11. Relevance of 123I-BMIPP delayed scintigraphic imaging for patients with angina pectoris – a pilot study

    PubMed Central

    Koyama, Kohei; Akashi, Yoshihiro J.; Kida, Keisuke; Suzuki, Kengo; Ishibashi, Yuki; Musha, Haruki; Banach, Maciej

    2011-01-01

    Introduction The study was designed to clarify the role of 123I-β-methyl-iodophenylpentadecanoic acid (123I-BMIPP) in the evaluation of myocardial fatty acid metabolism in patients with stable angina pectoris (AP) before and after percutaneous coronary intervention (PCI). Material and methods Ten controls (mean age: 70.4 ±10.5 years) and 12 patients with AP (mean age: 67.4 ±11.6 years) and single vessel coronary artery disease participated in the radionuclide cardiac study. Scintigraphic images were acquired at 30 min and at 4 h after 123I-BMIPP injection to determine early and delayed BMIPP uptake, respectively. The heart-to-mediastinum (H/M) ratio and the washout rate (WR) were calculated from the planar images. All patients underwent scintigraphy one day before PCI and again 1 month after successful PCI. Results No significant differences in the early or delayed H/M ratios were observed between the patients and the controls before PCI (early: 2.70 ±0.36 vs. 2.73 ±0.57; delayed: 2.26 ±0.33 vs. 2.40 ±0.43; p > 0.2 for both). The early and delayed H/M ratios remained unchanged with the comparison with before PCI (early: 2.72 ±0.27, delayed: 2.23 ±0.22; p > 0.2 for both). The global WR before PCI was significantly higher in the patients than in the control group (36.7 ±9.3%, vs. 28.1 ±8.2%, p = 0.02). However, the WR after PCI did not significantly differ between the patients and the controls (34.3 ±7.8% vs. 28.1 ±8.2%, p = 0.1). Conclusions These data may suggest that the WR of 123I-BMIPP determined from the planar images enhances the presence of myocardial ischaemia. PMID:22295024

  12. Chloride ligation in inorganic manganese model compounds relevant to Photosystem II studied using X-ray absorption spectroscopy

    PubMed Central

    Pizarro, Shelly A.; Visser, Hendrik; Cinco, Roehl M.; Robblee, John H.; Pal, Samudranil; Mukhopadhyay, Sumitra; Mok, Henry J.; Sauer, Kenneth; Wieghardt, Karl; Armstrong, William H.

    2014-01-01

    Chloride ions are essential for proper function of the photosynthetic oxygen-evolving complex (OEC) of Photosystem II (PS II). Although proposed to be directly ligated to the Mn cluster of the OEC, the specific structural and mechanistic roles of chloride remain unresolved. This study utilizes X-ray absorption spectroscopy (XAS) to characterize the Mn–Cl interaction in inorganic compounds that contain structural motifs similar to those proposed for the OEC. Three sets of model compounds are examined; they possess core structures MnIV3O4X (X = Cl, F, or OH) that contain a di-μ-oxo and two mono-μ-oxo bridges or MnIV2O2X (X = Cl, F, OH, OAc) that contain a di-μ-oxo bridge. Each set of compounds is examined for changes in the XAS spectra that are attributable to the replacement of a terminal OH or F ligand, or bridging OAc ligand, by a terminal Cl ligand. The X-ray absorption near edge structure (XANES) shows changes in the spectra on replacement of OH, OAc, or F by Cl ligands that are indicative of the overall charge of the metal atom and are consistent with the electronegativity of the ligand atom. Fourier transforms (FTs) of the extended X-ray absorption fine structure (EXAFS) spectra reveal a feature that is present only in compounds where chloride is directly ligated to Mn. These FT features were simulated using various calculated Mn–X interactions (X = O, N, Cl, F), and the best fits were found when a Mn–Cl interaction at a 2.2–2.3 Å bond distance was included. There are very few high-valent Mn halide complexes that have been synthesized, and it is important to make such a comparative study of the XANES and EXAFS spectra because they have the potential for providing information about the possible presence or absence of halide ligation to the Mn cluster in PS II. PMID:14758524

  13. Applicability of the DPPH assay for evaluating the antioxidant capacity of food additives - inter-laboratory evaluation study -.

    PubMed

    Shimamura, Tomoko; Sumikura, Yoshihiro; Yamazaki, Takeshi; Tada, Atsuko; Kashiwagi, Takehiro; Ishikawa, Hiroya; Matsui, Toshiro; Sugimoto, Naoki; Akiyama, Hiroshi; Ukeda, Hiroyuki

    2014-01-01

    An inter-laboratory evaluation study was conducted in order to evaluate the antioxidant capacity of food additives by using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Four antioxidants used as existing food additives (i.e., tea extract, grape seed extract, enju extract, and d-α-tocopherol) and 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox) were used as analytical samples, and 14 laboratories participated in this study. The repeatability relative standard deviation (RSD(r)) of the IC50 of Trolox, four antioxidants, and the Trolox equivalent antioxidant capacity (TEAC) were 1.8-2.2%, 2.2-2.9%, and 2.1-2.5%, respectively. Thus, the proposed DPPH assay showed good performance within the same laboratory. The reproducibility relative standard deviation (RSD(R)) of IC50 of Trolox, four antioxidants, and TEAC were 4.0-7.9%, 6.0-11%, and 3.7-9.3%, respectively. The RSD(R)/RSD(r) values of TEAC were lower than, or nearly equal to, those of IC50 of the four antioxidants, suggesting that the use of TEAC was effective for reducing the variance among the laboratories. These results showed that the proposed DPPH assay could be used as a standard method to evaluate the antioxidant capacity of food additives.

  14. The causal relevance of body mass index in different histological types of lung cancer: A Mendelian randomization study

    PubMed Central

    Carreras-Torres, Robert; Haycock, Philip C.; Relton, Caroline L.; Martin, Richard M.; Smith, George Davey; Kraft, Peter; Gao, Chi; Tworoger, Shelley; Le Marchand, Loïc; Wilkens, Lynne R.; Park, Sungshim L.; Haiman, Christopher; Field, John K.; Davies, Michael; Marcus, Michael; Liu, Geoffrey; Caporaso, Neil E.; Christiani, David C.; Wei, Yongyue; Chen, Chu; Doherty, Jennifer A.; Severi, Gianluca; Goodman, Gary E.; Hung, Rayjean J.; Amos, Christopher I.; McKay, James; Johansson, Mattias; Brennan, Paul

    2016-01-01

    Body mass index (BMI) is inversely associated with lung cancer risk in observational studies, even though it increases the risk of several other cancers, which could indicate confounding by tobacco smoking or reverse causality. We used the two-sample Mendelian randomization (MR) approach to circumvent these limitations of observational epidemiology by constructing a genetic instrument for BMI, based on results from the GIANT consortium, which was evaluated in relation to lung cancer risk using GWAS results on 16,572 lung cancer cases and 21,480 controls. Results were stratified by histological subtype, smoking status and sex. An increase of one standard deviation (SD) in BMI (4.65 Kg/m2) raised the risk for lung cancer overall (OR = 1.13; P = 0.10). This was driven by associations with squamous cell (SQ) carcinoma (OR = 1.45; P = 1.2 × 10−3) and small cell (SC) carcinoma (OR = 1.81; P = 0.01). An inverse trend was seen for adenocarcinoma (AD) (OR = 0.82; P = 0.06). In stratified analyses, a 1 SD increase in BMI was inversely associated with overall lung cancer in never smokers (OR = 0.50; P = 0.02). These results indicate that higher BMI may increase the risk of certain types of lung cancer, in particular SQ and SC carcinoma. PMID:27487993

  15. The study of plasma's modification effects in viscose used as an absorbent for wound-relevant fluids.

    PubMed

    Peršin, Zdenka; Devetak, Miha; Drevenšek-Olenik, Irena; Vesel, Alenka; Mozetič, Miran; Stana-Kleinschek, Karin

    2013-08-14

    Extreme non-equilibrium oxygen plasma was used for the deep functionalisation of viscose materials used for the healing of chronic wounds. Those thermal effects, which usually appear during plasma treatment due to the influence of charged particles, were avoided effectively by using electrode-less discharge at a very low power density of 25 W/l volume. A huge flux of neutrally reactive atoms at room temperature of 3x10(23)m(-2)s(-1), allowed for the effective diffusion of O-atoms into inter-fibril space and thus the activation of fibrils throughout the non-woven materials. Apart from the standard Wilhelmy balance and pedant drop method for determining the absorption dynamics on a macroscopic scale, optical polarisation microscopy was applied for studying the microscopic effects. The sorption characteristics were determined for saline solution, exudate, and blood and the results showed a dramatic improvement. Focusing on hydrophobic recovery prevention, the modified samples were stored for 10 days in air, nitrogen, and argon atmospheres. Some ageing effects occurred, whilst the absorption properties were independent of the storage atmosphere.

  16. Effect of environmentally-relevant concentrations of nonylphenol on sexual differentiation in zebrafish: a multi-generational study

    PubMed Central

    Sun, Dong; Chen, Qi; He, Ning; Diao, Pan-pan; Jia, Li-xing; Duan, Shun-shan

    2017-01-01

    Nonylphenol (NP) is a persistent environmental chemical that can disrupt the organism’s endocrine system, and is detected in the surface water and sea. In this study, we investigated whether NP can alter transcriptional expression of sexual differentiation-related genes. Three generations of zebrafish were exposed to 0, 2, 20 and 200 μg·L−1 of NP, and transcriptional expression of sexual differentiation genes were assessed in 10, 20 and 40 dpf in the F1 and F2 generations. Growth of zebrafish exposed to 200 μg·L−1 of NP was inhibited at 125 dpf in the F1 generation. 20 μg·L−1 of NP resulted in 80% females in the F1 generation, but had no effect on the F2 generation. In terms of the sexual differentiation genes, the transcriptional expression of cyp19a1a and esr1 genes were upregulated in 20 μg·L−1 of NP in the F1 generation. But expression of the sexual differentiation genes were not affected in the F2 generation. Overall, NP could affect sexual differentiation and gene transcriptional expression in the F1 generation. The tolerance of contaminant in the offsprings was improved at low concentration. PMID:28230098

  17. Human Processing of Behaviorally Relevant and Irrelevant Absence of Expected Rewards: A High-Resolution ERP Study

    PubMed Central

    Nahum, Louis; Gabriel, Damien; Schnider, Armin

    2011-01-01

    Acute lesions of the posterior medial orbitofrontal cortex (OFC) in humans may induce a state of reality confusion marked by confabulation, disorientation, and currently inappropriate actions. This clinical state is strongly associated with an inability to abandon previously valid anticipations, that is, extinction capacity. In healthy subjects, the filtering of memories according to their relation with ongoing reality is associated with activity in posterior medial OFC (area 13) and electrophysiologically expressed at 220–300 ms. These observations indicate that the human OFC also functions as a generic reality monitoring system. For this function, it is presumably more important for the OFC to evaluate the current behavioral appropriateness of anticipations rather than their hedonic value. In the present study, we put this hypothesis to the test. Participants performed a reversal learning task with intermittent absence of reward delivery. High-density evoked potential analysis showed that the omission of expected reward induced a specific electrocortical response in trials signaling the necessity to abandon the hitherto reward predicting choice, but not when omission of reward had no such connotation. This processing difference occurred at 200–300 ms. Source estimation using inverse solution analysis indicated that it emanated from the posterior medial OFC. We suggest that the human brain uses this signal from the OFC to keep thought and behavior in phase with reality. PMID:21298049

  18. Similarities and differences of copper and zinc cations binding to biologically relevant peptides studied by vibrational spectroscopies.

    PubMed

    Schirer, Alicia; El Khoury, Youssef; Faller, Peter; Hellwig, Petra

    2017-03-20

    GHK and DAHK are biological peptides that bind both copper and zinc cations. Here we used infrared and Raman spectroscopies to study the coordination modes of both copper and zinc ions, at pH 6.8 and 8.9, correlating the data with the crystal structures that are only available for the copper-bound form. We found that Cu(II) binds to deprotonated backbone (amidate), the N-terminus and N(π) of the histidine side chain, in both GHK and DAHK, at pH 6.8 and 8.9. The data for the coordination of zinc at pH 6.8 points to two conformers including both nitrogens of a histidine residue. At pH 8.9, vibrational spectra of the ZnGHK complexes show that equilibria between monomers, oligomers exist, where deprotonated histidine residues as well as deprotonated amide nitrogen are involved in the coordination. A common feature is found: zinc cations coordinate to N(τ) and/or N(π) of the His leading to the formation of GHK and DAHK multimers. In contrast, Cu(II) binds His via N(π) regardless of the peptide, in a pH-independent manner.

  19. Effect of environmentally-relevant concentrations of nonylphenol on sexual differentiation in zebrafish: a multi-generational study

    NASA Astrophysics Data System (ADS)

    Sun, Dong; Chen, Qi; He, Ning; Diao, Pan-Pan; Jia, Li-Xing; Duan, Shun-Shan

    2017-02-01

    Nonylphenol (NP) is a persistent environmental chemical that can disrupt the organism’s endocrine system, and is detected in the surface water and sea. In this study, we investigated whether NP can alter transcriptional expression of sexual differentiation-related genes. Three generations of zebrafish were exposed to 0, 2, 20 and 200 μg·L‑1 of NP, and transcriptional expression of sexual differentiation genes were assessed in 10, 20 and 40 dpf in the F1 and F2 generations. Growth of zebrafish exposed to 200 μg·L‑1 of NP was inhibited at 125 dpf in the F1 generation. 20 μg·L‑1 of NP resulted in 80% females in the F1 generation, but had no effect on the F2 generation. In terms of the sexual differentiation genes, the transcriptional expression of cyp19a1a and esr1 genes were upregulated in 20 μg·L‑1 of NP in the F1 generation. But expression of the sexual differentiation genes were not affected in the F2 generation. Overall, NP could affect sexual differentiation and gene transcriptional expression in the F1 generation. The tolerance of contaminant in the offsprings was improved at low concentration.

  20. Theoretical, spectroscopic, and mechanistic studies on transition-metal dinitrogen complexes: implications to reactivity and relevance to the nitrogenase problem.

    PubMed

    Studt, Felix; Tuczek, Felix

    2006-09-01

    Dinitrogen complexes of transition metals exhibit different binding geometries of N2 (end-on terminal, end-on bridging, side-on bridging, side-on end-on bridging), which are investigated by spectroscopy and DFT calculations, analyzing their electronic structure and reactivity. For comparison, a bis(mu-nitrido) complex, where the N--N bond has been split, has been studied as well. Most of these systems are highly covalent, and have strong metal-nitrogen bonds. In the present review, particular emphasis is put on a consideration of the activation of the coordinated dinitrogen ligand, making it susceptible to protonation, reactions with electrophiles or cleavage. In this context, theoretical, structural, and spectroscopic data giving informations on the amount of charge on the N2 unit are presented. The orbital interactions leading to a charge transfer from the metals to the dinitrogen ligand and the charge distribution within the coordinated N2 group are analyzed. Correlations between the binding mode and the observed reactivity of N2 are discussed.