Science.gov

Sample records for 4-6 times higher

  1. 15 CFR 4.6 - Time limits and expedited processing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... GOVERNMENT INFORMATION Freedom of Information Act § 4.6 Time limits and expedited processing. (a) In general... true and correct to the best of that person's knowledge and belief, explaining in detail the basis...

  2. Higher Education for Our Time

    ERIC Educational Resources Information Center

    Burnett, Dana D.; Collins, Natalia D.

    2010-01-01

    Public higher education is currently experiencing a decline in financial support from state governments, an acceleration of enrollment growth, and a shift from a transformational to a transactional student relationship. Private institutions are also struggling with increasing operational costs, and decreases in revenue from endowments and…

  3. Part Time Study in Higher Education.

    ERIC Educational Resources Information Center

    Neville, Colin

    This document, which is intended for adults considering enrolling in part-time study in higher education, examines the objectives and experiences of adults who have pursued part-time study in higher education in the United Kingdom. The following reasons why adults return to higher education are discussed: personal development; self-fulfillment;…

  4. 2,4,6-Trichlorophenol

    Integrated Risk Information System (IRIS)

    2,4,6 - Trichlorophenol ; CASRN 88 - 06 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcino

  5. Higher Education: A Time for Triage?

    NASA Astrophysics Data System (ADS)

    Lagowski, J. J.

    1995-10-01

    Higher education faces unprecedented challenges. The confluence of changing economic and demographic tends; new patterns of federal and state spending; more explicit expectations by students and their families for affordable, accessible education; and heightened scrutiny by those who claim a legitimate interest in higher education is inescapably altering the environment in which this system operates. Higher education will never again be as it was before. Further, many believe that tinkering around the margins is no longer an adequate response to the new demands. Fundamental change is deemed necessary to meet the challenge of this melange of pressures. A number of commentators have observed that political and corporate America have responded to their challenges by instituting a fundamental restructuring of those institutions. The medical community is also in the midst of a similar basic restructuring of the health care delivery system in this country. Now its education's turn. People are questioning the historically expressed mission of higher education. They make the claim that we cost too much, spend carelessly, teach poorly, plan myopically, and when questioned, act defensively. Educational administrators, from department chairs up, are confronted with the task of simultaneously reforming and cutting back. They have no choice. They must establish politically sophisticated priority settings and effect a hard-nosed reallocation of resources in a social environment where competing public needs have equivalent--or stronger--emotional pulls. Triage in a medical context involves confronting an emergency in which the demand for attention far outstrips available assistance by establishing a sequence of care in which one key individual orchestrates the application of harsh priorities which have been designed to maximize the number of survivors. In recent years, the decisions that have been made in some centers of higher education bear a striking similarity. The literature

  6. Representing 30 Years of Higher Education Change: UK Universities and the "Times Higher"

    ERIC Educational Resources Information Center

    Gewirtz, Sharon; Cribb, Alan

    2013-01-01

    This paper argues that the "Times Higher" provides a powerful tool for understanding the changing character of UK higher education (HE) and can usefully be seen as representative, and in some ways constitutive, of that changing character. Drawing on an analysis of a sample of stories from the "Times Higher," it documents the…

  7. Just in Time Research: Data Breaches in Higher Education

    ERIC Educational Resources Information Center

    Grama, Joanna

    2014-01-01

    This "Just in Time" research is in response to recent discussions on the EDUCAUSE Higher Education Information Security Council (HEISC) discussion list about data breaches in higher education. Using data from the Privacy Rights Clearinghouse, this research analyzes data breaches attributed to higher education. The results from this…

  8. Part-Time Higher Education: Employer Engagement under Threat?

    ERIC Educational Resources Information Center

    Mason, Geoff

    2014-01-01

    Employer support for employees who are studying part-time for higher education qualifications constitutes a form of indirect employer engagement with higher education institutions that has contributed strongly to the development of work-related skills and knowledge over the years. However, this form of employer engagement with higher education…

  9. The Times Higher Education Ranking Product: Visualising Excellence through Media

    ERIC Educational Resources Information Center

    Stack, Michelle L.

    2013-01-01

    This paper will examine the Times Higher Education's (THE) World University Rankings as a corporate media product. A number of empirical studies have critiqued the methodology of the THE, yet individuals, Higher Education Institutions (HEIs) and governments continue to use them for decision-making. This paper analyses the influence of…

  10. Higher Education in Recessionary Times: A UK Colloquium

    ERIC Educational Resources Information Center

    Evans, Mary

    2010-01-01

    This article talks about a meeting on "Higher Education in Recessionary Times" on March 24, 2010, which was hosted by the Society for Higher Education Research Policy Network. Although the meeting did take place in the context of an expected General Election, and on budget day, there was a general sense on the day that whoever won the…

  11. Real-Time N2O Gas Detection System for Agricultural Production Using a 4.6-μm-Band Laser Source Based on a Periodically Poled LiNbO3 Ridge Waveguide

    PubMed Central

    Tokura, Akio; Asobe, Masaki; Enbutsu, Koji; Yoshihara, Toshihiro; Hashida, Shin-nosuke; Takenouchi, Hirokazu

    2013-01-01

    This article describes a gas monitoring system for detecting nitrous oxide (N2O) gas using a compact mid-infrared laser source based on difference-frequency generation in a quasi-phase-matched LiNbO3 waveguide. We obtained a stable output power of 0.62 mW from a 4.6-μm-band continuous-wave laser source operating at room temperature. This laser source enabled us to detect atmospheric N2O gas at a concentration as low as 35 parts per billion. Using this laser source, we constructed a new real-time in-situ monitoring system for detecting N2O gas emitted from potted plants. A few weeks of monitoring with the developed detection system revealed a strong relationship between nitrogen fertilization and N2O emission. This system is promising for the in-situ long-term monitoring of N2O in agricultural production, and it is also applicable to the detection of other greenhouse gases. PMID:23921829

  12. Adopting Consumer Time: Potential Issues for Higher Education

    ERIC Educational Resources Information Center

    Gibbs, Paul

    2009-01-01

    Time and temporality have received little attention in the consumerism, marketing or, until recently, higher education literature. This paper attempts to compare the notions of timing implicit in education as "paideia" (transitional personal growth) with that implicit in consumerism and the marketing practices which foster it. This…

  13. Quantum Theory of Antisymmetric Higher Rank Tensor Gauge Field in Higher Dimensional Space-Time

    NASA Astrophysics Data System (ADS)

    Kimura, T.

    1981-01-01

    In a higher dimensional space-time, the Lagrangian formalism and the canonical operator formalism of covariant quantization of the antisymmetric tensor gauge field of higher rank are formulated consistently by introducing BRS transformation and Lagrangian multiplier fields From the effective Lagrangian, the numbers of the physical components and the effective ghosts are counted correctly without referring to a special reference frame. The confinement of unphysical components is assured from the viewpoint of the ``quartet mechanism'' of Kugo and Ojima.

  14. Does the Timing of Tracking Affect Higher Education Completion?

    ERIC Educational Resources Information Center

    van Elk, Roel; van der Steeg, Marc; Webbink, Dinand

    2011-01-01

    This paper investigates the effect of the timing of tracking on completion of higher education by exploiting unique variation from the Dutch education system. At the age of 12 Dutch students can enrol in tracked schools or in comprehensive schools. The comprehensive schools postpone enrolment into tracked classes by one or two years. OLS- and…

  15. Naked singularities in higher dimensional Vaidya space-times

    SciTech Connect

    Ghosh, S. G.; Dadhich, Naresh

    2001-08-15

    We investigate the end state of the gravitational collapse of a null fluid in higher-dimensional space-times. Both naked singularities and black holes are shown to be developing as the final outcome of the collapse. The naked singularity spectrum in a collapsing Vaidya region (4D) gets covered with the increase in dimensions and hence higher dimensions favor a black hole in comparison to a naked singularity. The cosmic censorship conjecture will be fully respected for a space of infinite dimension.

  16. Wormhole in higher-dimensional space-time

    NASA Astrophysics Data System (ADS)

    Shinkai, Hisa-aki; Torii, Takashi

    2015-04-01

    We introduce our recent studies on wormhole, especially its stability aspect in higher-dimensional space-time both in general relativity and in Gauss-Bonnet gravity. We derived the Ellis-type wormhole solution in n-dimensional general relativity, and found existence of an unstable mode in its linear perturbation analysis. We also evolved it numerically in dualnullcoordinate system, and confirmed its instability. The wormhole throat will change into black hole horizons for the input of the (relatively) positive energy, while it will change into inflationary expansion for the (relatively) negative energy input. If we add Gauss-Bonnet terms (higher curvature correction terms in gravity), then wormhole tends to expand (or change to black hole) if the coupling constant α is positive (negative), and such bifurcation of the throat horizon is observed earlier in higher dimension.

  17. Efficient multiple time-stepping algorithms of higher order

    NASA Astrophysics Data System (ADS)

    Demirel, Abdullah; Niegemann, Jens; Busch, Kurt; Hochbruck, Marlis

    2015-03-01

    Multiple time-stepping (MTS) algorithms allow to efficiently integrate large systems of ordinary differential equations, where a few stiff terms restrict the timestep of an otherwise non-stiff system. In this work, we discuss a flexible class of MTS techniques, based on multistep methods. Our approach contains several popular methods as special cases and it allows for the easy construction of novel and efficient higher-order MTS schemes. In addition, we demonstrate how to adapt the stability contour of the non-stiff time-integration to the physical system at hand. This allows significantly larger timesteps when compared to previously known multistep MTS approaches. As an example, we derive novel predictor-corrector (PCMTS) schemes specifically optimized for the time-integration of damped wave equations on locally refined meshes. In a set of numerical experiments, we demonstrate the performance of our scheme on discontinuous Galerkin time-domain (DGTD) simulations of Maxwell's equations.

  18. Programming real-time executives in higher order language

    NASA Technical Reports Server (NTRS)

    Foudriat, E. C.

    1982-01-01

    Methods by which real-time executive programs can be implemented in a higher order language are discussed, using HAL/S and Path Pascal languages as program examples. Techniques are presented by which noncyclic tasks can readily be incorporated into the executive system. Situations are shown where the executive system can fail to meet its task scheduling and yet be able to recover either by rephasing the clock or stacking the information for later processing. The concept of deadline processing is shown to enable more effective mixing of time and information synchronized systems.

  19. A higher-order Robert-Asselin type time filter

    NASA Astrophysics Data System (ADS)

    Li, Yong; Trenchea, Catalin

    2014-02-01

    The Robert-Asselin (RA) time filter combined with leapfrog scheme is widely used in numerical models of weather and climate. It successfully suppresses the spurious computational mode associated with the leapfrog method, but it also weakly dampens the physical mode and degrades the numerical accuracy. The Robert-Asselin-Williams (RAW) time filter is a modification of the RA filter that reduces the undesired numerical damping of RA filter and increases the accuracy. We propose a higher-order Robert-Asselin (hoRA) type time filter which effectively suppresses the computational modes and achieves third-order accuracy with the same storage requirement as RAW filter. Like RA and RAW filters, the hoRA filter is non-intrusive, and so it would be easily implementable. The leapfrog scheme with hoRA filter is almost as accurate, stable and efficient as the intrusive third-order Adams-Bashforth (AB3) method.

  20. Higher order time integration methods for two-phase flow

    NASA Astrophysics Data System (ADS)

    Kees, Christopher E.; Miller, Cass T.

    Time integration methods that adapt in both the order of approximation and time step have been shown to provide efficient solutions to Richards' equation. In this work, we extend the same method of lines approach to solve a set of two-phase flow formulations and address some mass conservation issues from the previous work. We analyze these formulations and the nonlinear systems that result from applying the integration methods, placing particular emphasis on their index, range of applicability, and mass conservation characteristics. We conduct numerical experiments to study the behavior of the numerical models for three test problems. We demonstrate that higher order integration in time is more efficient than standard low-order methods for a variety of practical grids and integration tolerances, that the adaptive scheme successfully varies the step size in response to changing conditions, and that mass balance can be maintained efficiently using variable-order integration and an appropriately chosen numerical model formulation.

  1. Full-Time Students? Term-Time Employment among Higher Education Students in Ireland

    ERIC Educational Resources Information Center

    Darmody, Merike; Smyth, Emer

    2008-01-01

    A good deal of research has focused on part-time employment among full-time students in higher education. However, little attention has been paid to the way in which these patterns may reflect societally specific processes rather than universal trends. This paper examines ways in which the higher education system itself can influence variation in…

  2. Too much noise in the Times Higher Education rankings.

    PubMed

    Bookstein, Fred L; Seidler, Horst; Fieder, Martin; Winckler, Georg

    2010-10-01

    Several individual indicators from the Times Higher Education Survey (THES) data base-the overall score, the reported staff-to-student ratio, and the peer ratings-demonstrate unacceptably high fluctuation from year to year. The inappropriateness of the summary tabulations for assessing the majority of the "top 200" universities would be apparent purely for reason of this obvious statistical instability regardless of other grounds of criticism. There are far too many anomalies in the change scores of the various indices for them to be of use in the course of university management.

  3. 43 CFR 3802.4-6 - Inspection.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MINING CLAIMS UNDER THE GENERAL MINING LAWS Exploration and Mining, Wilderness Review Program § 3802.4-6 Inspection. The authorized officer shall...

  4. 4-6 Computer Awareness. Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education, Winnipeg. Computer Services Branch.

    This guide was developed to assist teachers in achieving goals related to the development of computer awareness in students in grades 4-6 in the Canadian province of Manitoba. An overview of the program describes a set of basic concepts, skills, and attitudes relating to computer technology, and provides information on activities that can be used…

  5. A Dogrib History. Grade 4-6.

    ERIC Educational Resources Information Center

    Fraser, Tara

    A publication on the history and traditional lifestyle of the Dogrib Tribe of Canada's Northwest Territories is intended for use in grades 4-6. The text is illustrated with numerous drawings. Sections describe the caribou, spruce tree, muskox, fox, ducks and geese and their usefulness to Dogrib people. Activities covered are trading at the trading…

  6. 2,3,4,6-Tetrachlorophenol

    Integrated Risk Information System (IRIS)

    2,3,4,6 - Tetrachlorophenol ; CASRN 58 - 90 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncar

  7. Career Education: Grades 4-6.

    ERIC Educational Resources Information Center

    Cortland-Madison Board of Cooperative Educational Services, Cortland, NY.

    The third of a series of nine career education guides includes four social studies units for grades 4-6. Part one, famous Americans from Plymouth Rock to Tranquility Base, includes goals, objectives, skills to be taught or reviewed, lists of famous Americans in the fields of science and medicine, inventions, sports, religion, politics, literature,…

  8. 2,4,6-Trinitrotoluene (TNT)

    Integrated Risk Information System (IRIS)

    2,4,6 - Trinitrotoluene ( TNT ) ; CASRN 118 - 96 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for N

  9. Improved Continuous-Time Higher Harmonic Control Using Hinfinity Methods

    NASA Astrophysics Data System (ADS)

    Fan, Frank H.

    The helicopter is a versatile aircraft that can take-off and land vertically, hover efficiently, and maneuver in confined space. This versatility is enabled by the main rotor, which also causes undesired harmonic vibration during operation. This unwanted vibration has a negative impact on the practicality of the helicopter and also increases its operational cost. Passive control techniques have been applied to helicopter vibration suppression, but these methods are generally heavy and are not robust to changes in operating conditions. Feedback control offers the advantages of robustness and potentially higher performance over passive control techniques, and amongst the various feedback schemes, Shaw's higher harmonic control algorithm has been shown to be an effective method for attenuating harmonic disturbance in helicopters. In this thesis, the higher harmonic disturbance algorithm is further developed to achieve improved performance. One goal in this thesis is to determine the importance of periodicity in the helicopter rotor dynamics for control synthesis. Based on the analysis of wind tunnel data and simulation results, we conclude the helicopter rotor can be modeled reasonably well as linear and time-invariant for control design purposes. Modeling the helicopter rotor as linear time-invariant allows us to apply linear control theory concepts to the higher harmonic control problem. Another goal in this thesis is to find the limits of performance in harmonic disturbance rejection. To achieve this goal, we first define the metrics to measure the performance of the controller in terms of response speed and robustness to changes in the plant dynamics. The performance metrics are incorporated into an Hinfinity control problem. For a given plant, the resulting Hinfinity controller achieves the maximum performance, thus allowing us to identify the performance limitation in harmonic disturbance rejection. However, the Hinfinity controllers are of high order, and may

  10. Pulse transmission transmitter including a higher order time derivate filter

    DOEpatents

    Dress, Jr., William B.; Smith, Stephen F.

    2003-09-23

    Systems and methods for pulse-transmission low-power communication modes are disclosed. A pulse transmission transmitter includes: a clock; a pseudorandom polynomial generator coupled to the clock, the pseudorandom polynomial generator having a polynomial load input; an exclusive-OR gate coupled to the pseudorandom polynomial generator, the exclusive-OR gate having a serial data input; a programmable delay circuit coupled to both the clock and the exclusive-OR gate; a pulse generator coupled to the programmable delay circuit; and a higher order time derivative filter coupled to the pulse generator. The systems and methods significantly reduce lower-frequency emissions from pulse transmission spread-spectrum communication modes, which reduces potentially harmful interference to existing radio frequency services and users and also simultaneously permit transmission of multiple data bits by utilizing specific pulse shapes.

  11. Polymer quantization, stability and higher-order time derivative terms

    NASA Astrophysics Data System (ADS)

    Cumsille, Patricio; Reyes, Carlos M.; Ossandon, Sebastian; Reyes, Camilo

    2016-03-01

    The possibility that fundamental discreteness implicit in a quantum gravity theory may act as a natural regulator for ultraviolet singularities arising in quantum field theory has been intensively studied. Here, along the same expectations, we investigate whether a nonstandard representation called polymer representation can smooth away the large amount of negative energy that afflicts the Hamiltonians of higher-order time derivative theories, rendering the theory unstable when interactions come into play. We focus on the fourth-order Pais-Uhlenbeck model which can be reexpressed as the sum of two decoupled harmonic oscillators one producing positive energy and the other negative energy. As expected, the Schrödinger quantization of such model leads to the stability problem or to negative norm states called ghosts. Within the framework of polymer quantization we show the existence of new regions where the Hamiltonian can be defined well bounded from below.

  12. Measuring Stratigraphic Congruence Across Trees, Higher Taxa, and Time

    PubMed Central

    O'Connor, Anne; Wills, Matthew A.

    2016-01-01

    The congruence between the order of cladistic branching and the first appearance dates of fossil lineages can be quantified using a variety of indices. Good matching is a prerequisite for the accurate time calibration of trees, while the distribution of congruence indices across large samples of cladograms has underpinned claims about temporal and taxonomic patterns of completeness in the fossil record. The most widely used stratigraphic congruence indices are the stratigraphic consistency index (SCI), the modified Manhattan stratigraphic measure (MSM*), and the gap excess ratio (GER) (plus its derivatives; the topological GER and the modified GER). Many factors are believed to variously bias these indices, with several empirical and simulation studies addressing some subset of the putative interactions. This study combines both approaches to quantify the effects (on all five indices) of eight variables reasoned to constrain the distribution of possible values (the number of taxa, tree balance, tree resolution, range of first occurrence (FO) dates, center of gravity of FO dates, the variability of FO dates, percentage of extant taxa, and percentage of taxa with no fossil record). Our empirical data set comprised 647 published animal and plant cladograms spanning the entire Phanerozoic, and for these data we also modeled the effects of mean age of FOs (as a proxy for clade age), the taxonomic rank of the clade, and the higher taxonomic group to which it belonged. The center of gravity of FO dates had not been investigated hitherto, and this was found to correlate most strongly with some measures of stratigraphic congruence in our empirical study (top-heavy clades had better congruence). The modified GER was the index least susceptible to bias. We found significant differences across higher taxa for all indices; arthropods had lower congruence and tetrapods higher congruence. Stratigraphic congruence—however measured—also varied throughout the Phanerozoic

  13. Measuring Stratigraphic Congruence Across Trees, Higher Taxa, and Time.

    PubMed

    O'Connor, Anne; Wills, Matthew A

    2016-09-01

    The congruence between the order of cladistic branching and the first appearance dates of fossil lineages can be quantified using a variety of indices. Good matching is a prerequisite for the accurate time calibration of trees, while the distribution of congruence indices across large samples of cladograms has underpinned claims about temporal and taxonomic patterns of completeness in the fossil record. The most widely used stratigraphic congruence indices are the stratigraphic consistency index (SCI), the modified Manhattan stratigraphic measure (MSM*), and the gap excess ratio (GER) (plus its derivatives; the topological GER and the modified GER). Many factors are believed to variously bias these indices, with several empirical and simulation studies addressing some subset of the putative interactions. This study combines both approaches to quantify the effects (on all five indices) of eight variables reasoned to constrain the distribution of possible values (the number of taxa, tree balance, tree resolution, range of first occurrence (FO) dates, center of gravity of FO dates, the variability of FO dates, percentage of extant taxa, and percentage of taxa with no fossil record). Our empirical data set comprised 647 published animal and plant cladograms spanning the entire Phanerozoic, and for these data we also modeled the effects of mean age of FOs (as a proxy for clade age), the taxonomic rank of the clade, and the higher taxonomic group to which it belonged. The center of gravity of FO dates had not been investigated hitherto, and this was found to correlate most strongly with some measures of stratigraphic congruence in our empirical study (top-heavy clades had better congruence). The modified GER was the index least susceptible to bias. We found significant differences across higher taxa for all indices; arthropods had lower congruence and tetrapods higher congruence. Stratigraphic congruence-however measured-also varied throughout the Phanerozoic, reflecting

  14. Time-resolved spectral imaging: better photon economy, higher accuracy

    NASA Astrophysics Data System (ADS)

    Fereidouni, Farzad; Reitsma, Keimpe; Blab, Gerhard A.; Gerritsen, Hans C.

    2015-03-01

    Lifetime and spectral imaging are complementary techniques that offer a non-invasive solution for monitoring metabolic processes, identifying biochemical compounds, and characterizing their interactions in biological tissues, among other tasks. Newly developed instruments that perform time-resolved spectral imaging can provide even more information and reach higher sensitivity than either modality alone. Here we report a multispectral lifetime imaging system based on a field-programmable gate array (FPGA), capable of operating at high photon count rates (12 MHz) per spectral detection channel, and with time resolution of 200 ps. We performed error analyses to investigate the effect of gate width and spectral-channel width on the accuracy of estimated lifetimes and spectral widths. Temporal and spectral phasors were used for analysis of recorded data, and we demonstrated blind un-mixing of the fluorescent components using information from both modalities. Fractional intensities, spectra, and decay curves of components were extracted without need for prior information. We further tested this approach with fluorescently doubly-labeled DNA, and demonstrated its suitability for accurately estimating FRET efficiency in the presence of either non-interacting or interacting donor molecules.

  15. Advancing Knowledge in Higher Education: Universities in Turbulent Times

    ERIC Educational Resources Information Center

    Fitzgerald, Tanya, Ed.

    2014-01-01

    Over the last three decades, higher education institutions have experienced massive changes. In particular, institutions of higher education have been positioned as a means to contribute to the knowledge economy and gain a level of competitive advantage in the global marketplace. "Advancing Knowledge in Higher Education: Universities in…

  16. Alfvén wave in higher dimensional space time

    SciTech Connect

    Panigrahi, D.; Das, Ajanta; Chatterjee, S. E-mail: ajanta.das@heritageit.edu

    2009-09-01

    Following the wellknown spacetime decomposition technique as applied to (d+1) dimensions we write down the equations of magnetohydrodynamics (MHD) in a spatially flat generalised FRW universe. Assuming an equation of state for the background cosmic fluid we find solutions in turn for acoustic waves and also for Alfven waves in a warm (cold) magnetised plasma. Interestingly the different plasma modes closely resemble the flat space counterparts except that here the field variables all redshift with their time due to the expansion of the background. It is observed that in the ultrarelativistic limit the field parameters all scale as the free photon. The situation changes in the prerelativistic limit where the frequencies change in a bizarre fashion depending on initial conditions. It is observed that for a fixed magnetic field in a particular medium the Alfven wave velocity decreases with the number of dimensions, being the maximum in the usual 4D. Further for a fixed dimension the velocity attenuation is more significant in dust compared to the radiation era. We also find that in an expanding background the Alfven wave propagation is possible only in the high frequency range, determined by the strength of the external magnetic field, the mass density of the medium and also the dimensions of the spacetime. Further it is found that with expansion the cosmic magnetic field decays more sharply in higher dimensional cosmology, which is in line with observational demand.

  17. Ecuador's Higher Education System in Times of Change

    ERIC Educational Resources Information Center

    Van Hoof, Hubert B.; Estrella, Mateo; Eljuri, Marie-Isabel; León, Leonardo Torres

    2013-01-01

    Ecuador's higher education system is undergoing dramatic changes. The National Constitution of 2008 and the Higher Education Law of 2010 have changed the way Ecuador's universities are funded, administered, and accredited. The importance of research was elevated and drastic changes were made to the academic qualifications and employment conditions…

  18. Time Management and Academic Achievement of Higher Secondary Students

    ERIC Educational Resources Information Center

    Cyril, A. Vences

    2015-01-01

    The only thing, which can't be changed by man, is time. One cannot get back time lost or gone Nothing can be substituted for time. Time management is actually self management. The skills that people need to manage others are the same skills that are required to manage themselves. The purpose of the present study was to explore the relation between…

  19. Restyling the Humanities Curriculum of Higher Education for Posthuman Times

    ERIC Educational Resources Information Center

    Siddiqui, Jamila R.

    2016-01-01

    The future viability of the humanities in higher education has been broadly debated. Yet, most of these debates are missing an important consideration. The humanities' object of study is the human, an object that some would argue has been replaced in our onto-epistemological systems by the posthuman. In her 2013 book, "The Posthuman,"…

  20. Rebooting Irish Higher Education: Policy Challenges for Challenging Times

    ERIC Educational Resources Information Center

    Hazelkorn, Ellen

    2014-01-01

    The 2008 global financial crisis cast a long shadow over Ireland's higher education and research system. The IMF said Ireland experienced an "unprecedented economic correction", while Ireland's National Economic and Social Development Office said Ireland was beset by five different crises: a banking crisis, a fiscal crisis, an economic…

  1. Higher Education in Times of Financial Distress: The Minnesota Experience

    ERIC Educational Resources Information Center

    Severns, Roger

    2012-01-01

    Like many states, Minnesota has incurred large budget deficits during the past two years. Those deficits have, in turn, led to changes in a number of areas of state government, particularly higher education. Faculty have incurred pay freezes and layoffs, programs have closed, and tuition increased. Campuses within the MnSCU system have been…

  2. Time Management in Higher Education Administration: A Case Study.

    ERIC Educational Resources Information Center

    Lewis, Darrell R.; Dahl, Tor

    How do departmental chairpersons and deans in a major university setting manage their time? What are the major administrative activities and functions associated with such responsibilities? What relationships do these have with an ability to delegate, to control one's time for planning and self-initiated activities, or personal sense of…

  3. Time-resolved in situ detection of CO in a shock tube using cavity-enhanced absorption spectroscopy with a quantum-cascade laser near 4.6 µm.

    PubMed

    Sun, Kai; Wang, Shengkai; Sur, Ritobrata; Chao, Xing; Jeffries, Jay B; Hanson, Ronald K

    2014-10-06

    Cavity-enhanced absorption spectroscopy (CEAS) using a mid-infrared DFB quantum-cascade laser is reported for sensitive time-resolved (10 μs) in situ CO measurements in a shock tube. Off-axis alignment and fast scanning of the laser wavelength were used to minimize coupling noise in a low-finesse cavity. An absorption gain factor of 91 was demonstrated, which enabled sub-ppm detection sensitivity for gas temperatures of 1000-2100K in a 15 cm diameter shock tube. This substantial improvement in detection sensitivity compared to conventional single-pass absorption measurements, shows great potential for the study of reaction pathways of high-temperature combustion kinetics mechanisms in shock tubes.

  4. Time Management in Higher Education Administration: A Case Study

    ERIC Educational Resources Information Center

    Lewis, Darrell R.; Dahl, Tor

    1976-01-01

    Drawing on data from a staff development project for administrators in a college at a major American university, it was determined that there is considerable commonality across individuals and that it is possible to deal with such issues as time management, job stress, and enjoyment on an organizational level. (Editor/JT)

  5. 15 CFR 4.6 - Time limits and expedited processing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... component using multitrack processing may provide requesters in its slower track(s) with an opportunity to limit the scope of their requests in order to qualify for faster processing. A component doing so...

  6. 10 CFR 4.6 - Maintenance of records.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Maintenance of records. 4.6 Section 4.6 Energy NUCLEAR REGULATORY COMMISSION NONDISCRIMINATION IN FEDERALLY ASSISTED PROGRAMS OR ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE FROM THE COMMISSION General Provisions § 4.6 Maintenance of records. Each...

  7. 16 CFR 4.6 - Cooperation with other agencies.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Cooperation with other agencies. 4.6 Section 4.6 Commercial Practices FEDERAL TRADE COMMISSION ORGANIZATION, PROCEDURES AND RULES OF PRACTICE MISCELLANEOUS RULES § 4.6 Cooperation with other agencies. It is the policy of the Commission to cooperate...

  8. 16 CFR 4.6 - Cooperation with other agencies.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Cooperation with other agencies. 4.6 Section 4.6 Commercial Practices FEDERAL TRADE COMMISSION ORGANIZATION, PROCEDURES AND RULES OF PRACTICE MISCELLANEOUS RULES § 4.6 Cooperation with other agencies. It is the policy of the Commission to cooperate...

  9. 16 CFR 4.6 - Cooperation with other agencies.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Cooperation with other agencies. 4.6 Section 4.6 Commercial Practices FEDERAL TRADE COMMISSION ORGANIZATION, PROCEDURES AND RULES OF PRACTICE MISCELLANEOUS RULES § 4.6 Cooperation with other agencies. It is the policy of the Commission to cooperate...

  10. 16 CFR 4.6 - Cooperation with other agencies.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Cooperation with other agencies. 4.6 Section 4.6 Commercial Practices FEDERAL TRADE COMMISSION ORGANIZATION, PROCEDURES AND RULES OF PRACTICE MISCELLANEOUS RULES § 4.6 Cooperation with other agencies. It is the policy of the Commission to cooperate...

  11. 16 CFR 4.6 - Cooperation with other agencies.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Cooperation with other agencies. 4.6 Section 4.6 Commercial Practices FEDERAL TRADE COMMISSION ORGANIZATION, PROCEDURES AND RULES OF PRACTICE MISCELLANEOUS RULES § 4.6 Cooperation with other agencies. It is the policy of the Commission to cooperate...

  12. State Spending on Higher Education: Testing the Balance Wheel over Time

    ERIC Educational Resources Information Center

    Delaney, Jennifer A.; Doyle, William R.

    2011-01-01

    This article considers the role of higher education in state budgets. It empirically models and tests the balance wheel hypothesis in a robust framework. The balance wheel model posits that in good economic times, higher education is an attractive area for states to fund and tends to be funded at a higher rate than other state budget categories.…

  13. Part-Time Higher Education in English Colleges: Adult Identities in Diminishing Spaces

    ERIC Educational Resources Information Center

    Esmond, Bill

    2015-01-01

    Adult participation in higher education has frequently entailed mature students studying part time in lower-ranked institutions. In England, higher education policies have increasingly emphasised higher education provision in vocational further education colleges, settings which have extensive adult traditions but which mainly teach…

  14. Changing Times of Feminism and Higher Education: From Community to Employability

    ERIC Educational Resources Information Center

    Moss, Dorothy; Richter, Ingrid

    2011-01-01

    This article discusses the creation of space and time for feminist approaches in higher education in the context of shifting community and employment relations and the restructuring of higher education space-time. It draws on the reflections of three feminist academics concerning aspects of their work biographies in two very different higher…

  15. Time as the Fourth Dimension in the Globalization of Higher Education

    ERIC Educational Resources Information Center

    Walker, Judith

    2009-01-01

    This paper calls for an analysis of time to be integrated into the theories on the globalization of higher education. Specifically, the author argues that academic capitalism, fuelled by globalization, has led to changes in the university visible in time/space compression, time acceleration, the reification of time and our internalization of the…

  16. Time-delay at higher genus in high-energy open string scattering*

    NASA Astrophysics Data System (ADS)

    Kuroki, T.; Rey, S.-J.

    2001-02-01

    We explore some aspects of causal time-delay in open string scattering studied recently by Seiberg, Susskind and Toumbas. By examining high-energy scattering amplitudes at higher order in perturbation theory, we argue that causal time-delay at /Gth order is /1/(G+1) times smaller than the time-delay at tree level. We propose a space-time interpretation of the result by utilizing the picture of the high-energy open string scattering put forward by Gross and Mañes. We argue that the phenomenon of reduced time-delay is attributed to the universal feature of the space-time string trajectory in high-energy scattering that string shape at higher order remains the same as that at tree level but overall scale is reduced. We also discuss implications to the space-time uncertainty principle and make brief comments on causal time-delay behavior in space/time noncommutative field theory.

  17. Biodegradation of 2,4,6-trichlorophenol in a packed-bed biofilm reactor equipped with an internal net draft tube riser for aeration and liquid circulation.

    PubMed

    Jesús, A Gómez-De; Romano-Baez, F J; Leyva-Amezcua, L; Juárez-Ramírez, C; Ruiz-Ordaz, N; Galíndez-Mayer, J

    2009-01-30

    For the aerobic biodegradation of the fungicide and defoliant 2,4,6-trichlorophenol (2,4,6-TCP), a bench-scale packed-bed bioreactor equipped with a net draft tube riser for liquid circulation and oxygenation (PB-ALR) was constructed. To obtain a high packed-bed volume relative to the whole bioreactor volume, a high A(D)/A(R) ratio was used. Reactor's downcomer was packed with a porous support of volcanic stone fragments. PB-ALR hydrodynamics and oxygen mass transfer behavior was evaluated and compared to the observed behavior of the unpacked reactor operating as an internal airlift reactor (ALR). Overall gas holdup values epsilon(G), and zonal oxygen mass transfer coefficients determined at various airflow rates in the PB-ALR, were higher than those obtained with the ALR. When comparing mixing time values obtained in both cases, a slight increment in mixing time was observed when reactor was operated as a PB-ALR. By using a mixed microbial community, the biofilm reactor was used to evaluate the aerobic biodegradation of 2,4,6-TCP. Three bacterial strains identified as Burkholderia sp., Burkholderia kururiensis and Stenotrophomonas sp. constituted the microbial consortium able to cometabolically degrade the 2,4,6-TCP, using phenol as primary substrate. This consortium removed 100% of phenol and near 99% of 2,4,6-TCP. Mineralization and dehalogenation of 2,4,6-TCP was evidenced by high COD removal efficiencies ( approximately 95%), and by the stoichiometric release of chloride ions from the halogenated compound ( approximately 80%). Finally, it was observed that the microbial consortium was also capable to metabolize 2,4,6-TCP without phenol as primary substrate, with high removal efficiencies (near 100% for 2,4,6-TCP, 92% for COD and 88% for chloride ions).

  18. Pulse transmission receiver with higher-order time derivative pulse correlator

    DOEpatents

    Dress, Jr., William B.; Smith, Stephen F.

    2003-09-16

    Systems and methods for pulse-transmission low-power communication modes are disclosed. A pulse transmission receiver includes: a higher-order time derivative pulse correlator; a demodulation decoder coupled to the higher-order time derivative pulse correlator; a clock coupled to the demodulation decoder; and a pseudorandom polynomial generator coupled to both the higher-order time derivative pulse correlator and the clock. The systems and methods significantly reduce lower-frequency emissions from pulse transmission spread-spectrum communication modes, which reduces potentially harmful interference to existing radio frequency services and users and also simultaneously permit transmission of multiple data bits by utilizing specific pulse shapes.

  19. Part-Time Faculty in Colleges and Universities. 1981 Current Issues in Higher Education, No. 4.

    ERIC Educational Resources Information Center

    American Association for Higher Education, Washington, DC.

    Characteristics of part-time faculty, the legal position of part-time faculty, faculty development for part-timers, and other concerns are addressed in four papers. Thomas A. Emmet mentions the activities of some higher education associations with regard to the part-time employment issue and identifies 10 considerations for practices for these…

  20. Higher Education Students in Part-Time Work in a Chinese City

    ERIC Educational Resources Information Center

    Morrison, Keith

    2009-01-01

    This article discusses students taking part-time work whilst studying higher education (HE). It suggests that cross-national trends can be observed in the purposes, types, benefits, negative aspects and outcomes of part-time work by HE students. The paper reviews literature on HE students working part-time in the UK and the US, and UNESCO studies…

  1. A PI 4. 6 peroxidase that specifically crosslinks extensin precursors

    SciTech Connect

    Upham, B.L; Alizadeh, H.; Ryan, K.J.; Lamport, D.T.A. )

    1991-05-01

    The primary cell wall is a microcomposite of cellulose, pectin, hemicellulose and protein. The warp-weft model of the primary cell wall hypothesize that extensin monomers are intermolecularly crosslinked orthogonal to the cellulose microfibril thus mechanically coupling the major load-bearing polymer: cellulose. Media of tomato cell cultures contains heat labile, peroxide dependent crosslinking activity, as determined by the rate of decrease in monomer concentration analyzed via Superose-6. Isoelectric focusing of tomato cell culture media indicated crosslinking was predominantly in the acidic peroxidase fraction (pI4.6). This peroxidase was partially purified by ultracentrifugation, DEAE-Trisacryl and HPLC-DEAE chromatography techniques resulting in a 90 fold purification and 45% yield. A second acidic peroxidase eluted from the HPLC-DEAE column had 25% of the crosslinking activity of the pI 4.6 peroxidase. Purified basic peroxidase had only 0.7% of the activity of the pI 4.6 peroxidase. The specific activity of the pI 4.6 peroxidase was 5,473 mg extensin crosslinked/min/mg peroxidase. The pI 4.6 peroxidase crosslinked the following extensins: tomato I and II, carrot, Ginkgo II and did not crosslink Ginkgo I, Douglas Fir, Maize, Asparagus I and II, and sugarbeet extensins as well as bovine serum albumin. Comparison of motifs common to extensins that are crosslinked by the pI 4.6 peroxidase may help identify the crosslink domain(s) of extension.

  2. Risk of Birth Defects 20 Times Higher for Zika Moms: CDC

    MedlinePlus

    ... Birth Defects 20 Times Higher for Zika Moms: CDC Finding highlights importance of preventing infection during pregnancy, ... officer in the birth defects branch of the CDC, noted that in this report the investigators only ...

  3. Role of UV photolysis in accelerating the biodegradation of 2,4,6-TCP.

    PubMed

    Wang, Wenbing; Kirumba, George; Zhang, Yongming; Wu, Yanqing; Rittmann, Bruce E

    2015-09-18

    2,4,6-TCP, a kind of chlorinated aromatic and aliphatic compound, is difficult to be biodegraded by ordinary microorganisms. UV photolysis and biodegradation of 2,4,6-TCP by Bacillus amyloliquefaciens intimate coupling is a potential means to accelerate its biotransformation. The initial steps of 2,4,6-TCP biodegradation involve mono-oxygenation reactions that have molecular oxygen and an intracellular electron carrier as cosubstrates. It was demonstrated that B. amyloliquefaciens has the 2,4,6-TCP monooxygenase gene tcpA which could encode 2,4,6-TCP monooxygenase (TCP-MO). TCP-MO would catalytically decompose 2,4,6-TCP into 2,6-DCHQ. We employed an internal loop photolytic biofilm reactor for 2,4,6-TCP degradation. Sequentially coupled photolysis and biodegradation experimental results suggested that 2,4,6-TCP removal rate in P + B (TCP(UV) + phenol) protocol was higher by 77 and 103 % when compared to B (TCP + phenol) and B (TCP-only) protocols respectively. The corresponding loss rate coefficient (k) values were 0.069, 0.039, 0.034 mg/L·min(-1) respectively. This is because UV photolysis converted 2,4,6-TCP into its intermediates: 2,4-dichlorophenol (2,4-DCP), 4-monochlorophenol (4-MCP), phenol, 2,6-dichloro-p-hydroquinone (2,6-DCHQ), with all displaying less inhibition to bacterial action. In addition, phenol was the crucial UV-photolysis product from 2,4,6-TCP, its catabolic oxidation generating internal electron carriers that may accelerate the initial steps of 2,4,6-TCP biodegradation. Intimately coupled photolysis and biodegradation experimental results suggested that 2,4,6-TCP removal rate in P&B (TCP + phenol) protocol was higher by 166 and 681 % when compared to P&B (TCP-only) and P + B protocols respectively. The corresponding loss rate coefficient (k) values were 0.539, 0.203, 0.069 mg/L·min(-1) respectively. It provided sufficient evidence to demonstrate that intimately coupled photolysis and biodegradation accelerated 2,4,6-TCP

  4. Time Work by Overworked Professionals: Strategies in Response to the Stress of Higher Status

    PubMed Central

    Moen, Phyllis; Lam, Jack; Ammons, Samantha; Kelly, Erin L.

    2013-01-01

    How are professionals responding to the time strains brought on by the stress of their higher status jobs? Qualitative data from professionals reveal (a) general acceptance of the emerging temporal organization of professional work, including rising time demands and blurred boundaries around work/ nonwork times and places, and (b) time work as strategic responses to work intensification, overloads, and boundarylessness. We detected four time-work strategies: prioritizing time, scaling back obligations, blocking out time, and time shifting of obligations. These strategies are often more work-friendly than family-friendly, but “blocking out time” and “time shifting” suggest promising avenues for work-time policy and practice. PMID:24039337

  5. Concentrations of Polybrominated Diphenyl Ethers (PBDEs) and 2,4,6-Tribromophenol in Human Placental Tissues

    PubMed Central

    Leonetti, Christopher; Butt, Craig M.; Hoffman, Kate; Miranda, Marie Lynn; Stapleton, Heather M.

    2015-01-01

    Legacy environmental contaminants such as polybrominated diphenyl ethers (PBDEs) are widely detected in human tissues. However, few studies have measured PBDEs in placental tissues, and there are no reported measurements of 2,4,6-tribromophenol (2,4,6-TBP) in placental tissues. Measurements of these contaminants are important for understanding potential fetal exposures, as these compounds have been shown to alter thyroid hormone regulation in vitro and in vivo. In this study, we measured a suite of PBDEs and 2,4,6-TBP in 102 human placental tissues collected between 2010–2011 in Durham County, North Carolina, USA. The most abundant PBDE congener detected was BDE-47, with a mean concentration of 5.09 ng/g lipid (range: 0.12–141 ng/g lipid; detection frequency 91%); however, 2,4,6-TBP was ubiquitously detected and present at higher concentrations with a mean concentration of 15.4 ng/g lipid (range:1.31–316 ng/g lipid; detection frequency 100%). BDE-209 was also detected in more than 50% of the samples, and was significantly associated with 2,4,6-TBP in placental tissues, suggesting they may have a similar source, or that 2,4,6-TBP may be a degradation product of BDE-209. Interestingly, BDE-209 and 2,4,6-TBP were negatively associated with age (rs=−0.16; p=0.10 and rs=−0.17; p=0.08, respectively). The results of this work indicate that PBDEs and 2,4,6-TBP bioaccumulate in human placenta tissue and likely contribute to prenatal exposures to these environmental contaminants. Future studies are needed to determine if these joint exposures are associated with any adverse health measures in infants and children. PMID:26700418

  6. Part-time Faculty Job Satisfaction in Higher Education: A Literature Review

    ERIC Educational Resources Information Center

    Howell, Scott L.; Hoyt, Jeff

    2007-01-01

    The purpose of this literature review was to inform researchers of those predictive factors of job satisfaction previously identified for part-time faculty in higher education. They used the information gathered to help develop a survey instrument that was administered to 700 part-time faculty at their own institution. The results of the study,…

  7. Preparation and Support for Part-Time Teachers in Higher Education: Case Studies of Departmental Practice.

    ERIC Educational Resources Information Center

    Forster, Fred, Comp.; Thompson, Sheila, Comp.

    This publication presents 14 departmental case studies of the preparation and support provided to part-time teachers in Scottish institutions of higher education. The case studies are grouped in four sections according to the category of part-time staff involved: practicing professionals (professional teaching assistants, lawyers, artists, and…

  8. The Supply of Part-Time Higher Education in the UK. Research Report

    ERIC Educational Resources Information Center

    Callender, Claire; Birkbeck, Anne Jamieson; Mason, Geoff

    2010-01-01

    This report explores the supply of part-time higher education in the UK, with particular consideration to the study of part-time undergraduate provision in England. It is the final publication in the series of reports on individual student markets that were commissioned by Universities UK following the publication of the reports on the Future size…

  9. Insulin-like growth factor binding proteins 4-6.

    PubMed

    Bach, Leon A

    2015-10-01

    Insulin-like growth factor binding proteins (IGFBPs) 4-6 have important roles as modulators of IGF actions. IGFBP-4 and IGFBP-6 predominantly inhibit IGF actions, whereas IGFBP-5 may enhance these actions under some circumstances. IGFBP-6 is unique among the IGFBPs for its marked IGF-II binding preference. IGFBPs 4-6 are found in the circulation as binary complexes with IGFs that can enter tissues. Additionally, about half of the circulating IGFBP-5 is found in ternary complexes with IGFs and an acid labile subunit; this high molecular complex cannot leave the circulation and acts as an IGF reservoir. IGFBPs 4-6 also have IGF-independent actions. These IGFBPs are regulated in a cell-specific manner and their dysregulation may play a role in a range of diseases including cancer. However, there is no clear clinical indication for measuring serum levels of these IGFBPs at present.

  10. Creating Sacred Places for Children in Grades 4-6.

    ERIC Educational Resources Information Center

    Fox, Sandra J.

    This guide attempts to help teachers of American Indian children in grades 4-6 provide a culturally relevant education that takes place in the regular classroom, includes content related to Indian students' lives, makes students proud, expands to other experiences, and enhances learning. Creating sacred places means responding appropriately to…

  11. Learn about Seabirds. Teaching Packet, Grades 4-6.

    ERIC Educational Resources Information Center

    Fish and Wildlife Service (Dept. of Interior), Anchorage, AK.

    This teaching packet is designed to teach Alaskan students in grades 4-6 about Alaska's seabird populations, the worldwide significance of seabirds, and the environmental conditions to which seabirds are sensitive. The packet includes a curriculum guide (containing a teacher's background story and 12 teaching activities), a separately published…

  12. First CDK 4/6 Inhibitor Heads to Market.

    PubMed

    2015-04-01

    The FDA granted accelerated approval to palbociclib for the treatment of estrogen receptor-positive, HER2-negative metastatic breast cancer in postmenopausal women who have not yet received endocrine-based therapy. Palbociclib is the first cell cycle-targeting CDK 4/6 inhibitor to reach the market.

  13. 2,4,6-TRINITROTOLUENE TRANSFORMATION IN PLANTED, SOIL COLUMNS

    EPA Science Inventory

    2,4,6-Trinitrotoluene (TNT), has been used extensively by the United States military to manufacture explosive devices. Since the conclusion of World War 11, many of these military installations have also been involved in the disposal of surplus and outdated explosives. Both the c...

  14. 4,6-Dinitro-o-cyclohexyl phenol

    Integrated Risk Information System (IRIS)

    4,6 - Dinitro - o - cyclohexyl phenol ; CASRN 131 - 89 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments

  15. Health Promotion Activity Book for Grades 4-6.

    ERIC Educational Resources Information Center

    Ohio State Dept. of Health, Columbus.

    This book of activities is designed to supplement health lessons for students in grades 4-6. Some of the activities are quite simple and require very little instruction and direction, while others are more difficult and require careful explanation prior to completion. The level of difficulty of the activities is varied in order to create both…

  16. Council Minutes, February 4-6, 2011: Santa Monica, California

    ERIC Educational Resources Information Center

    Educational Researcher, 2011

    2011-01-01

    This article presents minutes of the American Educational Research Association's meetings held in Santa Monica, California, on February 4-6, 2011. President Kris D. Gutierrez led a discussion of the meeting dates for the summer Executive Board and Council meetings. It was agreed that members of Council will be polled to determine the best dates…

  17. Higher order finite-time consensus protocol for heterogeneous multi-agent systems

    NASA Astrophysics Data System (ADS)

    Zhou, Yingjiang; Yu, Xinghuo; Sun, Changyin; Yu, Wenwu

    2015-02-01

    This paper studies the higher order finite-time consensus protocol for heterogeneous multi-agent systems (HMASs). By adding a power integrator method and using heterogeneous domination method, two kinds of consensus protocols are proposed with state feedback and output feedback, respectively. First, for the leaderless and leader-follower HMASs, the continuous finite-time consensus protocols are proposed. Then, by designing a finite-time observer, the output-feedback finite-time consensus protocol is developed. Finally, simulations are performed to illustrate the effectiveness of the theoretical results.

  18. Finite time control for MIMO nonlinear system based on higher-order sliding mode.

    PubMed

    Liu, Xiangjie; Han, Yaozhen

    2014-11-01

    Considering a class of MIMO uncertain nonlinear system, a novel finite time stable control algorithm is proposed based on higher-order sliding mode concept. The higher-order sliding mode control problem of MIMO nonlinear system is firstly transformed into finite time stability problem of multivariable system. Then continuous control law, which can guarantee finite time stabilization of nominal integral chain system, is employed. The second-order sliding mode is used to overcome the system uncertainties. High frequency chattering phenomenon of sliding mode is greatly weakened, and the arbitrarily fast convergence is reached. The finite time stability is proved based on the quadratic form Lyapunov function. Examples concerning the triple integral chain system with uncertainty and the hovercraft trajectory tracking are simulated respectively to verify the effectiveness and the robustness of the proposed algorithm.

  19. Higher-Order, Space-Time Adaptive Finite Volume Methods: Algorithms, Analysis and Applications

    SciTech Connect

    Minion, Michael

    2014-04-29

    The four main goals outlined in the proposal for this project were: 1. Investigate the use of higher-order (in space and time) finite-volume methods for fluid flow problems. 2. Explore the embedding of iterative temporal methods within traditional block-structured AMR algorithms. 3. Develop parallel in time methods for ODEs and PDEs. 4. Work collaboratively with the Center for Computational Sciences and Engineering (CCSE) at Lawrence Berkeley National Lab towards incorporating new algorithms within existing DOE application codes.

  20. An efficient higher-order PML in WLP-FDTD method for time reversed wave simulation

    NASA Astrophysics Data System (ADS)

    Wei, Xiao-Kun; Shao, Wei; Ou, Haiyan; Wang, Bing-Zhong

    2016-09-01

    Derived from a stretched coordinate formulation, a higher-order complex frequency shifted (CFS) perfectly matched layer (PML) is proposed for the unconditionally stable finite-difference time-domain (FDTD) method based on weighted Laguerre polynomials (WLPs). The higher-order PML is implemented with an auxiliary differential equation (ADE) approach. In order to further improve absorbing performance, the parameter values of stretching functions in the higher-order PML are optimized by the multi-objective genetic algorithm (MOGA). The optimal solutions can be chosen from the Pareto front for trading-off between two independent objectives. It is shown in a numerical test that the higher-order PML is efficient in terms of attenuating propagating waves and reducing late time reflections. Moreover, the higher-order PML can be placed very close to the wall when analyzing the channel characteristics of time reversal (TR) waves in a multipath indoor environment. Numerical examples of TR wave propagation demonstrate the availability of the proposed method.

  1. Institutional View of Part-Time Faculty Management in Higher Education Institutes in China

    ERIC Educational Resources Information Center

    Li, Zhifeng; Jiang, Xiulan; Li, Hongbo

    2007-01-01

    Part-time faculty has become an important labor force in Chinese colleges and universities. The number of them has risen rapidly and its structure varies in different types of higher education institutes (HEIs), which results from integration of the social motivation and the inner motivation of schools' reform. From the institutional point of…

  2. Curriculum Characteristics of Time-Compressed Course in a U.S. Higher Education Institution

    ERIC Educational Resources Information Center

    Hyun, Eunsook; Kretovics, Mark; Crowe, Alicia

    2006-01-01

    The study explored characteristics of the curriculum practice of higher education faculty in the context of time-compressed (e.g., 5-6 weeks) courses as compared with regular term (15-16 weeks) courses. The researchers used open-ended questions on a web-based survey at a large doctoral-extensive university in a Midwestern state in the United…

  3. "Times Higher Education" 100 under 50 Ranking: Old Wine in a New Bottle?

    ERIC Educational Resources Information Center

    Soh, Kaycheng

    2013-01-01

    "Times Higher Education" 100 under 50 ranking is a new twist to the university ranking. It focuses on universities that have a history of 50 years or less with the purpose of offsetting the advantage of prestige of the older ones. This article re-analysed the data publicly available and looked into relevant conceptual and statistical issues. The…

  4. What Determines Employment of Part-Time Faculty in Higher Education Institutions?

    ERIC Educational Resources Information Center

    Liu, Xiangmin; Zhang, Liang

    2007-01-01

    This study uses a cross-section national sample of four-year colleges and universities in the United States to examine the variation of part-time faculty employment. Results of this study suggest that higher educational institutions actively design and adopt contingent work arrangements to save on labor costs and to manage their resource…

  5. Analyzing the Anglo-American Hegemony in the "Times Higher Education" Rankings

    ERIC Educational Resources Information Center

    Kaba, Amadu Jacky

    2012-01-01

    This study analyzes the 2009 "Times Higher Education"-QS top 200 universities in the world. Based on this analysis the study claims that the THS reflects the phenomenon of Anglo American hegemony. The United States with 54 universities and the United Kingdom with 29 dominated the THS. In addition, six out of every ten universities on the…

  6. Inequalities in Entry to Higher Education: A Comparison over Time between Scotland and England and Wales

    ERIC Educational Resources Information Center

    Iannelli, Cristina

    2007-01-01

    This paper uses data from the Scottish School Leavers Surveys and the England and Wales Youth Cohort Study to analyse changes over time in gender and social class inequalities in the opportunities of young people to participate in higher education (HE) in Scotland, England and Wales. The results show that in Great Britain, in the period from the…

  7. Laser photo-oxidative degradation of 4,6-dimethyldibenzothiophene.

    PubMed

    Gondal, M A; Masoudi, H M; Pola, J

    2008-04-01

    Degradation of 4,6-dimethyldibenzothiophene (DMDBT), persistent sulfur contaminant in fuel oils has been achieved in non-polar phase by laser-irradiating DMDBT alone and in the presence of hydrogen peroxide and molecular oxygen. The most efficient degradation in the presence of molecular oxygen is judged to be the first example of self-sensitized photo-oxygenation of thiophenes, in which DMDBT sequentially acts as 1O2 sensitizer and reactant.

  8. Inositol 1,3,4,6-tetrakisphosphate mobilizes calcium in Xenopus oocytes with high potency.

    PubMed Central

    Ivorra, I; Gigg, R; Irvine, R F; Parker, I

    1991-01-01

    Injection of Ins(1,3,4,6)P4 into Xenopus oocytes evoked Ca2(+)-dependent membrane currents with a potency 5-10 times less than Ins(1,4,5)P3, whereas Ins(1,3,4)P3 and Ins(1,3,4,5,6)P5 were almost ineffective. Responses to Ins(1,3,4,6)P4 arose through liberation of intracellular Ca2+ and through entry of extracellular Ca2+. These results, together with the observation that Ins(1,3,4,6)P4 facilitated responses to Ins(1,4,5)P3, suggests that both of these compounds may act on the same intracellular receptors. PMID:1991032

  9. American Higher Education in 1975 and 1976: The Academy's Response to Continuing Kondratieff Recession as Reported in "The Times Higher Education Supplement" (London).

    ERIC Educational Resources Information Center

    Hawley, John B.; And Others

    Articles on American higher education that appeared in 1975 and 1976 in "The Times Higher Education Supplement" (London) are analyzed in connection with two statements about American society and its economy. These statements are Joseph A. Schumpeter's 1939 analysis of business cycles, and James B. Shuman's and Davis Rosenau's 1972…

  10. Calculating Higher-Order Moments of Phylogenetic Stochastic Mapping Summaries in Linear Time.

    PubMed

    Dhar, Amrit; Minin, Vladimir N

    2017-02-08

    Stochastic mapping is a simulation-based method for probabilistically mapping substitution histories onto phylogenies according to continuous-time Markov models of evolution. This technique can be used to infer properties of the evolutionary process on the phylogeny and, unlike parsimony-based mapping, conditions on the observed data to randomly draw substitution mappings that do not necessarily require the minimum number of events on a tree. Most stochastic mapping applications simulate substitution mappings only to estimate the mean and/or variance of two commonly used mapping summaries: the number of particular types of substitutions (labeled substitution counts) and the time spent in a particular group of states (labeled dwelling times) on the tree. Fast, simulation-free algorithms for calculating the mean of stochastic mapping summaries exist. Importantly, these algorithms scale linearly in the number of tips/leaves of the phylogenetic tree. However, to our knowledge, no such algorithm exists for calculating higher-order moments of stochastic mapping summaries. We present one such simulation-free dynamic programming algorithm that calculates prior and posterior mapping variances and scales linearly in the number of phylogeny tips. Our procedure suggests a general framework that can be used to efficiently compute higher-order moments of stochastic mapping summaries without simulations. We demonstrate the usefulness of our algorithm by extending previously developed statistical tests for rate variation across sites and for detecting evolutionarily conserved regions in genomic sequences.

  11. Time-domain multimode dispersion measurement in a higher-order-mode fiber.

    PubMed

    Cheng, Ji; Pedersen, Martin E V; Wang, Ke; Xu, Chris; Grüner-Nielsen, Lars; Jakobsen, Dan

    2012-02-01

    We present a new multimode dispersion measurement technique based on the time-of-flight method. The modal delay and group velocity dispersion of all excited modes in a few-mode fiber can be measured simultaneously by a tunable pulsed laser and a high speed sampling oscilloscope. A newly designed higher-order-mode fiber with large anomalous dispersion in the LP(02) mode has been characterized using this method, and experimental results are in good agreement with the designed dispersion values. The demonstrated technique is significantly simpler to implement than the existing frequency-domain or interferometry-based methods.

  12. Maxwell times in higher-order generalized hydrodynamics: Classical fluids, and carriers and phonons in semiconductors.

    PubMed

    Rodrigues, Clóves G; Silva, Carlos A B; Ramos, José G; Luzzi, Roberto

    2017-02-01

    A family of what can be so-called Maxwell times which arises in the context of higher-order generalized hydrodynamics (HOGH; also called mesoscopic hydrothermodynamics) is evidenced. This is done in the framework of a HOGH built within a statistical formalism in terms of a nonequilibrium statistical ensemble formalism. It consists in a description in terms of the densities of particles and energy and their fluxes of all orders, with the motion described by a set of coupled nonlinear integro-differential equations involving them. These Maxwell times have a fundamental role in determining the type of hydrodynamic motion that the system would display in the given conditions and constraints. They determine a Maxwell viscous force not present in the usual hydrodynamic equations, for example, in Navier-Stokes equation.

  13. Maxwell times in higher-order generalized hydrodynamics: Classical fluids, and carriers and phonons in semiconductors

    NASA Astrophysics Data System (ADS)

    Rodrigues, Clóves G.; Silva, Carlos A. B.; Ramos, José G.; Luzzi, Roberto

    2017-02-01

    A family of what can be so-called Maxwell times which arises in the context of higher-order generalized hydrodynamics (HOGH; also called mesoscopic hydrothermodynamics) is evidenced. This is done in the framework of a HOGH built within a statistical formalism in terms of a nonequilibrium statistical ensemble formalism. It consists in a description in terms of the densities of particles and energy and their fluxes of all orders, with the motion described by a set of coupled nonlinear integro-differential equations involving them. These Maxwell times have a fundamental role in determining the type of hydrodynamic motion that the system would display in the given conditions and constraints. They determine a Maxwell viscous force not present in the usual hydrodynamic equations, for example, in Navier-Stokes equation.

  14. Aerobic biotransformation and mineralization of 2,4,6-trinitrotoluene

    SciTech Connect

    Bae, B.H.; Autenrieth, R.L.; Bonner, J.S.

    1995-12-31

    Respirometric mineralization studies of 2,4,6-trinitrotoluene (TNT) were conducted with microorganisms isolated from a site contaminated with munitions waste in Illinois. Nine aerobic bacterial species were isolated under a carbon- and nitrogen-limited condition and tentatively identified as: one Pseudomonas species; one Enterobacter species; and seven Alcaligenes species. Experiments were performed using each of the nine organisms individually and with a consortium of all nine bacterial species. The aerobic microorganisms were cultured in a sterile nutrient solution with glucose and 20 mg/L TNT. Mineralization was determined using uniformly ring-labeled {sup 14}C-TNT in a respirometer that trapped the evolved CO{sub 2}. Biodegradation behavior was characterized based on oxygen consumption, distribution of {sup 14}C activity, and high-performance liquid chromatography (HPLC) analysis of TNT and its transformation products.

  15. Time-Domain Analysis of Higher Order Mode Properties in an Open Cavity Retaining Axial Symmetry

    NASA Astrophysics Data System (ADS)

    Lin, S. Y.; Lin, M. C.

    2016-10-01

    Theoretical and computational research to accurately and efficiently determine higher order mode properties of an axially symmetrical open cavity has been pursued. Open cavities have been widely employed in gyrotrons for the generation of high-power millimeter, submillimeter, and THz waves. A standing wave forms in the main body of the cavity, and the open end allows the extraction of power generated by the electron beam wave interaction. On the other hand, microresonators, such as microspheres that have small effective volume of their whispering gallery modes (WGMs), high quality factors, and quasi insensitivity to conducting material boundaries can also be considered as open cavities since the WGMs are natural electromagnetic eigenmodes that are activated by external coherent signals. For these cavities, axial symmetry is usually retained. The CAVITY program developed by Professor K. R. Chu using Fortran allows the users to accurately and efficiently determine the resonant frequency, the quality factor, and the field profile for the TE modes of an open cavity. In this work, an extension of the CAVITY program using Mathematica, CAVITY-M, to perform time-domain analysis of higher order modes in open cavities retaining axial symmetry for wider applications such as those mentioned above has been carried out. The new CAVITY-M program developed using Mathematica is able to effectively analyze the higher order mode characteristics of a general open cavity with an axial symmetry, in addition to the traditional modes in a gyrotron cavity.

  16. Higher Order Time Integration Schemes for the Unsteady Navier-Stokes Equations on Unstructured Meshes

    NASA Technical Reports Server (NTRS)

    Jothiprasad, Giridhar; Mavriplis, Dimitri J.; Caughey, David A.; Bushnell, Dennis M. (Technical Monitor)

    2002-01-01

    The efficiency gains obtained using higher-order implicit Runge-Kutta schemes as compared with the second-order accurate backward difference schemes for the unsteady Navier-Stokes equations are investigated. Three different algorithms for solving the nonlinear system of equations arising at each timestep are presented. The first algorithm (NMG) is a pseudo-time-stepping scheme which employs a non-linear full approximation storage (FAS) agglomeration multigrid method to accelerate convergence. The other two algorithms are based on Inexact Newton's methods. The linear system arising at each Newton step is solved using iterative/Krylov techniques and left preconditioning is used to accelerate convergence of the linear solvers. One of the methods (LMG) uses Richardson's iterative scheme for solving the linear system at each Newton step while the other (PGMRES) uses the Generalized Minimal Residual method. Results demonstrating the relative superiority of these Newton's methods based schemes are presented. Efficiency gains as high as 10 are obtained by combining the higher-order time integration schemes with the more efficient nonlinear solvers.

  17. Time-dependent treatment of electron-hydrogen scattering for higher angular momenta (L>0)

    NASA Astrophysics Data System (ADS)

    Odero, D. O.; Peacher, J. L.; Schultz, D. R.; Madison, D. H.

    2001-02-01

    The time-dependent approach to electron-atom scattering is emerging as an alternative to more conventional methods of treating atomic collisions. Solving the time-dependent Schrödinger equation directly has several very attractive features including a completely nonperturbative solution, dense representation of the nonphysical positive energy states, circumvention of the need to explicitly impose boundary conditions for ionization, and the convenience of being able to ``watch'' the electronic probability density evolve though the collision. Two principal approaches have so far been applied to treat electron-atom scattering, namely, the time-dependent close couping (TDCC) method and what we refer to as the time-dependent Hylleraas (TDH) method. The TDCC method solves coupled equations with two variables within a truncated infinite sum over individual angular momenta for each total angular momentum L of the system. In contrast, the TDH method avoids an infinite summation over the angular momenta of the individual electrons at the expense of solving a coupled equation with three variables for each L. The TDH method has previously been used for L=0 only. An important question, therefore, concerns whether the TDH method would represent a numerical advantage over the TDCC method for higher L values. This issue is investigated in this paper.

  18. Higher Order Time Integration Schemes for the Unsteady Navier-Stokes Equations on Unstructured Meshes

    NASA Technical Reports Server (NTRS)

    Jothiprasad, Giridhar; Mavriplis, Dimitri J.; Caughey, David A.

    2002-01-01

    The rapid increase in available computational power over the last decade has enabled higher resolution flow simulations and more widespread use of unstructured grid methods for complex geometries. While much of this effort has been focused on steady-state calculations in the aerodynamics community, the need to accurately predict off-design conditions, which may involve substantial amounts of flow separation, points to the need to efficiently simulate unsteady flow fields. Accurate unsteady flow simulations can easily require several orders of magnitude more computational effort than a corresponding steady-state simulation. For this reason, techniques for improving the efficiency of unsteady flow simulations are required in order to make such calculations feasible in the foreseeable future. The purpose of this work is to investigate possible reductions in computer time due to the choice of an efficient time-integration scheme from a series of schemes differing in the order of time-accuracy, and by the use of more efficient techniques to solve the nonlinear equations which arise while using implicit time-integration schemes. This investigation is carried out in the context of a two-dimensional unstructured mesh laminar Navier-Stokes solver.

  19. Cork Taint of Wines: Role of the Filamentous Fungi Isolated from Cork in the Formation of 2,4,6-Trichloroanisole by O Methylation of 2,4,6-Trichlorophenol

    PubMed Central

    Álvarez-Rodríguez, María Luisa; López-Ocaña, Laura; López-Coronado, José Miguel; Rodríguez, Enrique; Martínez, María Jesús; Larriba, Germán; Coque, Juan-José R.

    2002-01-01

    Cork taint is a musty or moldy off-odor in wine mainly caused by 2,4,6-trichloroanisole (2,4,6-TCA). We examined the role of 14 fungal strains isolated from cork samples in the production of 2,4,6-TCA by O methylation of 2,4,6-trichlorophenol (2,4,6-TCP). The fungal strains isolated belong to the genera Penicillium (four isolates); Trichoderma (two isolates); and Acremonium, Chrysonilia, Cladosporium, Fusarium, Mortierella, Mucor, Paecilomyces, and Verticillium (one isolate each). Eleven of these strains could produce 2,4,6-TCA when they were grown directly on cork in the presence of 2,4,6-TCP. The highest levels of bioconversion were carried out by the Trichoderma and Fusarium strains. One strain of Trichoderma longibrachiatum could also efficiently produce 2,4,6-TCA in liquid medium. However, no detectable levels of 2,4,6-TCA production by this strain could be detected on cork when putative precursors other than 2,4,6-TCP, including several anisoles, dichlorophenols, trichlorophenols, or other highly chlorinated compounds, were tested. Time course expression studies with liquid cultures showed that the formation of 2,4,6-TCA was not affected by a high concentration of glucose (2% or 111 mM) or by ammonium salts at concentrations up to 60 mM. In T. longibrachiatum the O methylation of 2,4,6-TCP was catalyzed by a mycelium-associated S-adenosyl-l-methionine (SAM)-dependent methyltransferase that was strongly induced by 2,4,6-TCP. The reaction was inhibited by S-adenosyl-l-homocysteine, an inhibitor of SAM-dependent methylation, suggesting that SAM is the natural methyl donor. These findings increase our understanding of the mechanism underlying the origin of 2,4,6-TCA on cork, which is poorly understood despite its great economic importance for the wine industry, and they could also help us improve our knowledge about the biodegradation and detoxification processes associated with chlorinated phenols. PMID:12450804

  20. Pulse transmission receiver with higher-order time derivative pulse generator

    DOEpatents

    Dress, Jr., William B.; Smith, Stephen F.

    2003-08-12

    Systems and methods for pulse-transmission low-power communication modes are disclosed. A pulse transmission receiver includes: a front-end amplification/processing circuit; a synchronization circuit coupled to the front-end amplification/processing circuit; a clock coupled to the synchronization circuit; a trigger signal generator coupled to the clock; and at least one higher-order time derivative pulse generator coupled to the trigger signal generator. The systems and methods significantly reduce lower-frequency emissions from pulse transmission spread-spectrum communication modes, which reduces potentially harmful interference to existing radio frequency services and users and also simultaneously permit transmission of multiple data bits by utilizing specific pulse shapes.

  1. Fission Multiplicity Detection with Temporal Gamma-Neutron Discrimination from Higher-Order Time Correlation Statistics

    SciTech Connect

    Oberer, Richard B.

    2002-10-01

    The current practice of nondestructive assay (NDA) of fissile materials using neutrons is dominated by the 3He detector. This has been the case since the mid 1980s when Fission Multiplicity Detection (FMD) was replaced with thermal well counters and neutron multiplicity counting (NMC). The thermal well counters detect neutrons by neutron capture in the 3He detector subsequent to moderation. The process of detection requires from 30 to 60 μs. As will be explained in Section 3.3 the rate of detecting correlated neutrons (signal) from the same fission are independent of this time but the rate of accidental correlations (noise) are proportional to this time. The well counters are at a distinct disadvantage when there is a large source of uncorrelated neutrons present from (α, n) reactions for example. Plastic scintillating detectors, as were used in FMD, require only about 20 ns to detect neutrons from fission. One thousandth as many accidental coincidences are therefore accumulated. The major problem with the use of fast-plastic scintillation detectors, however, is that both neutrons and gamma rays are detected. The pulses from the two are indistinguishable in these detectors. For this thesis, a new technique was developed to use higher-order time correlation statistics to distinguish combinations of neutron and gamma ray detections in fast-plastic scintillation detectors. A system of analysis to describe these correlations was developed based on simple physical principles. Other sources of correlations from non-fission events are identified and integrated into the analysis developed for fission events. A number of ratios and metric are identified to determine physical properties of the source from the correlations. It is possible to determine both the quantity being measured and detection efficiency from these ratios from a single measurement without a separate calibration. To account for detector dead-time, an alternative analytical technique

  2. A novel fast gas chromatography method for higher time resolution measurements of speciated monoterpenes in air

    NASA Astrophysics Data System (ADS)

    Jones, C. E.; Kato, S.; Nakashima, Y.; Kajii, Y.

    2014-05-01

    Biogenic emissions supply the largest fraction of non-methane volatile organic compounds (VOC) from the biosphere to the atmospheric boundary layer, and typically comprise a complex mixture of reactive terpenes. Due to this chemical complexity, achieving comprehensive measurements of biogenic VOC (BVOC) in air within a satisfactory time resolution is analytically challenging. To address this, we have developed a novel, fully automated Fast Gas Chromatography (Fast-GC) based technique to provide higher time resolution monitoring of monoterpenes (and selected other C9-C15 terpenes) during plant emission studies and in ambient air. To our knowledge, this is the first study to apply a Fast-GC based separation technique to achieve quantification of terpenes in ambient air. Three chromatography methods have been developed for atmospheric terpene analysis under different sampling scenarios. Each method facilitates chromatographic separation of selected BVOC within a significantly reduced analysis time compared to conventional GC methods, whilst maintaining the ability to quantify individual monoterpene structural isomers. Using this approach, the C9-C15 BVOC composition of single plant emissions may be characterised within a 14.5 min analysis time. Moreover, in-situ quantification of 12 monoterpenes in unpolluted ambient air may be achieved within an 11.7 min chromatographic separation time (increasing to 19.7 min when simultaneous quantification of multiple oxygenated C9-C10 terpenoids is required, and/or when concentrations of anthropogenic VOC are significant). These analysis times potentially allow for a twofold to fivefold increase in measurement frequency compared to conventional GC methods. Here we outline the technical details and analytical capability of this chromatographic approach, and present the first in-situ Fast-GC observations of 6 monoterpenes and the oxygenated BVOC (OBVOC) linalool in ambient air. During this field deployment within a suburban forest

  3. Higher-order time integration of Coulomb collisions in a plasma using Langevin equations

    DOE PAGES

    Dimits, A. M.; Cohen, B. I.; Caflisch, R. E.; ...

    2013-02-08

    The extension of Langevin-equation Monte-Carlo algorithms for Coulomb collisions from the conventional Euler-Maruyama time integration to the next higher order of accuracy, the Milstein scheme, has been developed, implemented, and tested. This extension proceeds via a formulation of the angular scattering directly as stochastic differential equations in the two fixed-frame spherical-coordinate velocity variables. Results from the numerical implementation show the expected improvement [O(Δt) vs. O(Δt1/2)] in the strong convergence rate both for the speed |v| and angular components of the scattering. An important result is that this improved convergence is achieved for the angular component of the scattering if andmore » only if the “area-integral” terms in the Milstein scheme are included. The resulting Milstein scheme is of value as a step towards algorithms with both improved accuracy and efficiency. These include both algorithms with improved convergence in the averages (weak convergence) and multi-time-level schemes. The latter have been shown to give a greatly reduced cost for a given overall error level when compared with conventional Monte-Carlo schemes, and their performance is improved considerably when the Milstein algorithm is used for the underlying time advance versus the Euler-Maruyama algorithm. A new method for sampling the area integrals is given which is a simplification of an earlier direct method and which retains high accuracy. Lastly, this method, while being useful in its own right because of its relative simplicity, is also expected to considerably reduce the computational requirements for the direct conditional sampling of the area integrals that is needed for adaptive strong integration.« less

  4. Higher-order time integration of Coulomb collisions in a plasma using Langevin equations

    SciTech Connect

    Dimits, A. M.; Cohen, B. I.; Caflisch, R. E.; Rosin, M. S.; Ricketson, L. F.

    2013-02-08

    The extension of Langevin-equation Monte-Carlo algorithms for Coulomb collisions from the conventional Euler-Maruyama time integration to the next higher order of accuracy, the Milstein scheme, has been developed, implemented, and tested. This extension proceeds via a formulation of the angular scattering directly as stochastic differential equations in the two fixed-frame spherical-coordinate velocity variables. Results from the numerical implementation show the expected improvement [O(Δt) vs. O(Δt1/2)] in the strong convergence rate both for the speed |v| and angular components of the scattering. An important result is that this improved convergence is achieved for the angular component of the scattering if and only if the “area-integral” terms in the Milstein scheme are included. The resulting Milstein scheme is of value as a step towards algorithms with both improved accuracy and efficiency. These include both algorithms with improved convergence in the averages (weak convergence) and multi-time-level schemes. The latter have been shown to give a greatly reduced cost for a given overall error level when compared with conventional Monte-Carlo schemes, and their performance is improved considerably when the Milstein algorithm is used for the underlying time advance versus the Euler-Maruyama algorithm. A new method for sampling the area integrals is given which is a simplification of an earlier direct method and which retains high accuracy. Lastly, this method, while being useful in its own right because of its relative simplicity, is also expected to considerably reduce the computational requirements for the direct conditional sampling of the area integrals that is needed for adaptive strong integration.

  5. Occurrence of earthy and musty odor compounds (geosmin, 2-methylisoborneol and 2,4,6-trichloroanisole) in biologically treated wastewater.

    PubMed

    Urase, T; Sasaki, Y

    2013-01-01

    The concentrations of earthy and musty odor compounds (2-methylisoborneol (2-MIB), geosmin and 2,4,6-trichloroanisole (TCA)) in treated wastewater were measured. Concentrations of 2,4,6-TCA (4.3-37.7 ng/L) and geosmin (3.7-42.2 ng/L) higher than their odor thresholds were detected for effluents from large-scale treatment plants. The effluent from a small-scale wastewater plant treating toilet and kitchen wastewater contained the target earthy and musty odor compounds below the odor thresholds. The ozonation applied as an advanced wastewater treatment process was considerably more effective for the removal of 2,4,6-TCA than for the removal of 2-MIB and geosmin. The measured concentrations of 2,4,6-TCA in river environments without the influence of large-scale wastewater effluents were less than the odor threshold.

  6. Structural study of 2,4,6-triisopropylbenzenesulfonyl chloride

    SciTech Connect

    Laba, V. I. Sviridova, A. V.; Nesterov, V. N.

    2009-01-15

    The structure of 2,4,6-triisopropylbenzenesulfonyl chloride (TPSCl) (I) was studied by X-ray diffraction. Compound I is a highly selective condensing agent first suggested by Khorana for the formation of the C3'-C5' interribonucleotide linkage in the oligo- and polyribonucleotide synthesis. I crystals are orthorhombic. At -120 deg. C, the unit-cell parameters are a = 14.184(4) A, b = 11.344(5) A, c = 19.883(6) A, V = 3199(2) A{sup 3}, d{sub calc} = 1.257 g/cm{sup 3}, Z = 8, sp. gr. Pbca. Molecule I adopts a strongly flattened boat conformation with the carbon atoms C-SO{sub 2}Cl (C{sub 1}) and C-i-Pr (C4) of the benzene ring deviating from the bottom of the boat by 0.065(1) and 0.032(1) A, respectively. Molecule I is sterically overcrowded, resulting in an increase in the bond lengths and bond-angle distortions in the fragment containing the SO{sub 2}Cl group and two ortho-i-Pr groups. Nonbonded contacts that are present in the molecule can be considered weak intramolecular hydrogen bonds (for example, the (CH{sub 3}){sub 2}C-H-O=S bond). There is no rotation of the SO{sub 2}Cl, ortho-i-Pr, and CH{sub 3} groups. The above-mentioned facts are, apparently, responsible for the specific selectivity of TPSCl. New readily available sterically hindered arenesulfonyl chlorides were designed.

  7. Renewing Quality Assurance at a Time of Turbulence: An Attempt to Reenergise Quality in Australian Higher Education

    ERIC Educational Resources Information Center

    Shah, Mahsood; Nair, Chenicheri Sid

    2011-01-01

    The renewal of quality assurance in Australian higher education comes at a time when the higher education sectors in Australia and around the world are experiencing a number of key challenges. These include: ongoing decline in public funding of universities; the massification of higher education and demand for it during global recession;…

  8. a Computational Tddft Study on Intramolecular Charge Transfer in Di-Tert and 2,4,6-TRICYANOANILINES.

    NASA Astrophysics Data System (ADS)

    Fujiwara, Takashige; Zgierski, Marek Z.

    2014-06-01

    We have carried out TDDFT computational studies on the low-lying excited states of di-tert-butylaminobenzonitrile and 2,4,6-tricyanoaniline compounds that exhibit unusual photophysical behaviors associated with the intramolecular charge transfer (ICT). For both 3- and 4-di-tert-butylamino)benzonitriles (m-DTBABN and p-DTBABN, respectively) show the ICT formation, and p-DTBABN appears to be the only meta-substituted aminobenzonitrile that exhibits the ICT formation. The TDDFT calculations indicate evidence that the ultrafast ICT formation in p-DTBABN and m-DTBABN is due to the sequential state switches: ππ*(La)→ πσ*→ ICT in the presence of conical intersections among the three closely-lying excited-states. On the other hand, 2,4,6-tricyanoaniline does not show clear evidence for the LE (locally excited) state → ICT state formation from steady-state fluorescence studies, despite the greater electron acceptor strength of tricycanobenzene as compared to monocyanobenzene, which is part of a 4-(dimethylamino)benzonitrile (p-DMABN) compound. However, it is predicted that 2,4,6-tricyano-N,N-dimethylaniline (TCDMA), but not 2,4,6-tricyanoaniline (TCA), possesses two ICT states, which show the ICT-characterized quinoidal structures and lie below the initially photo-excited S1(ππ*) state. The CC2 calculations further predict two conformers as labeled with quinoidal (ICT--Q) and anti-quinoidal (ICT--AQ) structures are rapidly interconnecting with each other. The lower energy ICT--Q structure tends to be populated from the unstable ICT--AQ structure, which is responsible for the observed time-resolved fluorescence as well as the excited-state absorption from the mixed S1(ππ*)/ICT state of TCDMA. In both cases for TCDMA and TCA, the πσ* state locates significantly higher in energy than the S1(ππ*) state (and the ICT state for TCA), thus precluding the πσ*→ ICT formation, which is believed to occur in a p-DMABN in polar environments.

  9. Decreased transpiration in poplar trees exposed to 2,4,6-trinitrotoluene

    SciTech Connect

    Thompson, P.L.; Ramer, L.A.; Guffey, A.P.; Schnoor, J.L.

    1998-01-01

    The improper handling of the toxic compound 2,4,6-trinitrotoluene (TNT) has led to the contamination of soil and groundwater, and the uptake of TNT by a variety of plants has been established. This article discusses the effects of various concentrations of the explosive 2,4,6-trinitrotoluene (TNT) on the transpiration of hybrid poplar trees growing in hydroponic media. Transpiration was measured daily by gravimetric means. The rapid removal of TNT from hydroponic solutions was a result of plant uptake and required a daily dosage of TNT to ensure a relatively constant exposure over time. Transpiration decreased with increasing TNT concentrations {ge}5 mg/L. Decreases in transpiration were accompanied by leaf chlorosis and abscission. A comparison between a laboratory study and a pilot-scale experiment showed good scale-up potential.

  10. Bouncebacks in Higher Education Funding: Patterns in Length of Time to Recovery following Cuts in State Appropriations. WISCAPE Policy Brief

    ERIC Educational Resources Information Center

    Doyle, William R.; Delaney, Jennifer A.

    2011-01-01

    State appropriations for higher education are highly cyclical, with downturns in funding during difficult financial times followed by increases in funding when state finances improve. This policy brief shares recent research about whether the duration of recoveries from cuts in appropriations for higher education has changed over time and which…

  11. Biological Degradation of 2,4,6-Trinitrotoluene

    PubMed Central

    Esteve-Núñez, Abraham; Caballero, Antonio; Ramos, Juan L.

    2001-01-01

    Nitroaromatic compounds are xenobiotics that have found multiple applications in the synthesis of foams, pharmaceuticals, pesticides, and explosives. These compounds are toxic and recalcitrant and are degraded relatively slowly in the environment by microorganisms. 2,4,6-Trinitrotoluene (TNT) is the most widely used nitroaromatic compound. Certain strains of Pseudomonas and fungi can use TNT as a nitrogen source through the removal of nitrogen as nitrite from TNT under aerobic conditions and the further reduction of the released nitrite to ammonium, which is incorporated into carbon skeletons. Phanerochaete chrysosporium and other fungi mineralize TNT under ligninolytic conditions by converting it into reduced TNT intermediates, which are excreted to the external milieu, where they are substrates for ligninolytic enzymes. Most if not all aerobic microorganisms reduce TNT to the corresponding amino derivatives via the formation of nitroso and hydroxylamine intermediates. Condensation of the latter compounds yields highly recalcitrant azoxytetranitrotoluenes. Anaerobic microorganisms can also degrade TNT through different pathways. One pathway, found in Desulfovibrio and Clostridium, involves reduction of TNT to triaminotoluene; subsequent steps are still not known. Some Clostridium species may reduce TNT to hydroxylaminodinitrotoluenes, which are then further metabolized. Another pathway has been described in Pseudomonas sp. strain JLR11 and involves nitrite release and further reduction to ammonium, with almost 85% of the N-TNT incorporated as organic N in the cells. It was recently reported that in this strain TNT can serve as a final electron acceptor in respiratory chains and that the reduction of TNT is coupled to ATP synthesis. In this review we also discuss a number of biotechnological applications of bacteria and fungi, including slurry reactors, composting, and land farming, to remove TNT from polluted soils. These treatments have been designed to achieve

  12. Photoluminescence properties of a novel red emitting Ba10F2(PO4)6:Eu3+ phosphor

    NASA Astrophysics Data System (ADS)

    Peng, You-shun; Shi, Wei-wei; Han, Cong-lin; Kang, Yan-yan; Wang, Yan-su; Zhang, Zhi-wei

    2015-06-01

    A novel red-emitting phosphor Ba10F2(PO4)6:Eu3+ is synthesized by a high-temperature solid-state reaction. X-ray powder diffraction (XRD) analysis confirms the phase formation of Ba10F2(PO4)6:Eu3+ materials. The photoluminescence excitation (PLE) and emission (PL) spectra, the concentration dependence of the emission intensity, decay curves and Commission International de I'Eclairage (CIE) of the phosphors are investigated. It is observed that Ba10F2(PO4)6:Eu3+ phosphors exhibit two dominating bands situated at 591 and 616 nm, originating from the 5D0 → 7F1 and 5D0 → 7F2 transition of the Eu3+ ion, respectively. The decay time is also determined for various concentrations of Eu3+ in Ba10F2(PO4)6:Eu3+. Crystal lattice, PL spectra and decay time analysis indicate there exist two isolated Eu3+ crystallography sites in Ba10F2(PO4)6. The calculated color coordinates lie in the red region. Therefore, Ba10F2(PO4)6:Eu3+ phosphors may be good candidates for red components in near-UV (NUV) white LEDs.

  13. Reflections on the Field of Higher Education: Time, Space and Sub-Fields

    ERIC Educational Resources Information Center

    Yokoyama, Keiko

    2016-01-01

    The objective of this study is to define the field of higher education and clarify its identity. It examines three analytical dimensions which, it proposes, shape the field: knowledge, approach and community. It argues that contextual knowledge around the issue of higher education has defined the field but has not determined techniques that are…

  14. The Changing Faces of Corruption in Georgian Higher Education: Access through Times and Tests

    ERIC Educational Resources Information Center

    Orkodashvili, Mariam

    2012-01-01

    This article presents a comparative-historical analysis of access to higher education in Georgia. It describes the workings of corrupt channels during the Soviet and early post-Soviet periods and the role of standardized tests in fighting corruption in higher education admission processes after introduction of the Unified National Entrance…

  15. Department Chairs' Perceptions of Part-Time Faculty Status in Maryland Public and Private Higher Education Institutions

    ERIC Educational Resources Information Center

    Moorehead, Daniel L.

    2011-01-01

    The growing use of part-time, non-tenure track faculty in higher education has become a nationwide phenomenon. The college-teaching part-time instructor is one who is working for low pay, has little job security, and has few benefits. College part-time instructors' employment is in a contingent state. They do not have the job protection provided…

  16. Young Adults with Head Trauma May Have Higher Risk of Jail Time

    MedlinePlus

    ... THURSDAY, Dec. 8, 2016 (HealthDay News) -- A traumatic brain injury may be linked to a young adult's higher ... These findings contribute to emerging research suggesting traumatic brain injury is an important risk factor for involvement with ...

  17. Part-Time Students and Part-Time Study in Higher Education in the UK: Strand 1--A Quantitative Data Analysis of 2003/04 HESA Data

    ERIC Educational Resources Information Center

    Ramsden, Brian

    2006-01-01

    This is a report of the Strand 1 element of the Universities UK project to examine part-time students and part-time study within the United Kingdom. The aim of Strand 1 of this project is to set out, as far as possible, factual information about students studying part-time and following programmes of study leading to higher education…

  18. Monoclinic structure of hydroxylpyromorphite Pb10(PO4)6(OH)2 - hydroxylmimetite Pb10(AsO4)6(OH)2 solid solution series

    NASA Astrophysics Data System (ADS)

    Giera, Alicja; Manecki, Maciej; Borkiewicz, Olaf; Zelek, Sylwia; Rakovan, John; Bajda, Tomasz; Marchlewski, Tomasz

    2016-04-01

    Seven samples of hydroxyl analogues of pyromorphite-mimetite solid solutions series were synthesized from aqueous solutions at 80° C in a computer-controlled chemistate: 200 mL aqueous solutions of 0.05M Pb(NO3)2 and 0.03M KH2AsO4 and/or KH2PO4 were dosed with a 0.25 mL/min rate to a glass beaker, which initially contained 100 mL of distilled water. Constant pH of 8 was maintained using 2M KOH. The syntheses yielded homogeneous fine-grained white precipitates composition of which was close to theoretical Pb10[(PO4)6-x(AsO4)x](OH)2, where x = 0, 1, 2, 3, 4, 5, 6. High-resolution powder X-ray diffraction data were obtained in transmission geometry at the beamline 11-BM at the Advanced Photon Source (Argonne National Laboratory in Illinois, USA). The structure Rietveld refinements based on starting parameters of either hexagonal hydroxylpyromorphite or monoclinic mimetite-M were performed using GSAS+EXPGUI software. Apatite usually crystallizes in the hexagonal crystal system with the space group P63/m. For the first time, however, the lowering of the hexagonal to monoclinic crystal symmetry was observed in the hydroxyl variety of pyromorphite-mimetite solid solution series. This is indicated by better fitting of the modeled monoclinic structure to the experimental data. The same is not the case for analogous calcium hydroxylapatite series Ca5(PO4)3OH - Ca5(AsO4)3OH (Lee et al. 2009). Systematical linear increase of unit cell parameters is observed with As substitution from a=9.88, b=19.75, and c=7.43 for Pb10(PO4)6(OH)2 to a=10.23, b=20.32, and c=7.51 for Pb10(AsO4)6(OH)2. A strong pseudohexagonal character (γ ≈ 120° and b ≈ 2a) of the analyzed monoclinic phases was established. This work is partially funded by AGH research grant no 11.11.140.319 and partially by Polish NCN grant No 2011/01/M/ST10/06999. Lee Y.J., Stephens P.W., Tang Y., Li W., Philips B.L., Parise J.B., Reeder R.J., 2009. Arsenate substitution in hydroxylapatite: Structural characterization

  19. Mechanism of bioactivation and covalent binding of 2,4,6-trinitrotoluene.

    PubMed

    Leung, K H; Yao, M; Stearns, R; Chiu, S H

    1995-06-30

    Studies were undertaken to investigate the mechanism of bioactivation and covalent binding of TNT. Incubation of [14C]TNT with rat liver microsomes in the presence of an NADPH generating system resulted in metabolism and covalent binding to microsomal proteins. Time-dependence studies showed that TNT was rapidly reduced to yield 4-hydroxylamino-2,6-dinitrotoluene (4HA), 4-amino-2,6-dinitrotoluene (4A) and 2-amino-4,6-dinitrotoluene (2A) as intermediates which were further metabolized to form 2,4-diamino-6-nitrotoluene (2,4DA) and 2,6-diamino-4-nitrotoluene (2,6DA). In contrast to the rapid disappearance of TNT, formation of covalent protein adducts increased with time, suggesting that the reactive intermediate was likely to be formed not directly from TNT but from proximal intermediates such as 4HA. The hypothesis that 4HA was more readily converted to the reactive intermediate than TNT was further supported by the increased levels of covalent adduct formation when [14C]4HA was incubated directly with liver microsomes. Covalent binding of TNT and 4HA was dependent on oxygen concentration. Higher levels of covalent adducts were formed when TNT was incubated aerobically (up to 50% oxygen concentration) than under anaerobic conditions. Covalent binding of [14C]4HA also increased with increasing oxygen concentrations. These results suggest that the reactive intermediate is likely to be an oxidized metabolite of 4HA, e.g. 4-nitroso-2,6-dinitrotoluene. Compounds containing a free sulfhydryl group (cysteine, N-acetylcysteine, GSH or 3,4-dichlorobenzenethiol) decreased the amount of covalent binding to various degrees, suggesting the involvement of the sulfhydryl group in adduct formation with TNT following bioactivation. Metabolic activation of TNT by liver microsomes required NADPH but not NADH as the cofactor. Incubation of [14C]TNT with purified rat liver NADPH cytochrome P450 reductase under either aerobic or anaerobic conditions yielded exclusively 4HA. In contrast

  20. The Impact of Part-Time Faculty on Student Retention: A Case Study in Higher Education

    ERIC Educational Resources Information Center

    Smith, Curtis V.

    2010-01-01

    There has been considerable debate in community colleges over the last forty years regarding the impact of increased use of part-time faculty (PTF) on student learning. It has been argued that part-time faculty fail to provide the same level of teaching quality as full-time faculty (FTF). The purpose of this study was to determine the impact of…

  1. ZnO Catalyzed Efficient Synthesis of Some New 2-Substituted-4,6-diarylpyrimidines

    PubMed Central

    Ameta, K. L.; Kumar, Biresh; Rathore, Nitu S.

    2012-01-01

    A simple and efficient protocol is developed for the synthesis of 2-substituted-4,6-diarylpyrimidines from one-pot three-component reaction of 4′-hydroxy-3′,5′-dinitro substituted chalcones, S-benzylthiouronium chloride (SBT), and heterocyclic secondary amines (morpholine/pyrrolidine/piperidine) in the presence of 15 mol% of ZnO as a heterogeneous catalyst. The present methodology offers several advantages such as being a simple procedure as well as providing excellent yields, and short reaction time. The catalyst is inexpensive, stable, and can be easily recycled and reused for several cycles with consistent activity. PMID:24052838

  2. Optical properties of the (3.4.6.4) hexagonal Archimedean photonic crystal

    NASA Astrophysics Data System (ADS)

    Jovanović, Djordje; Gajić, Radoš

    2011-01-01

    We theoretically investigated the optical properties of the lesser known (3.4.6.4) Archimedean photonic crystal. The structure is two dimensional and made of dielectric GaAs rods in air. The calculations of the band structures, equifrequency contours, and simulations of the wave propagation through the structure were performed by the plane wave expansion and finite-difference time-domain methods. With analysis of the gap map and equifrequency contours we obtained frequency ranges for best performance for wave guiding. For those frequency ranges, we designed a new type of waveguide for possible applications in integrated optics. In addition, negative refraction was exhibited by the structure.

  3. Biotransformation of 2,4,6-trinitrotoluene in Anabaena sp. cultures

    SciTech Connect

    Pavlostathis, S.G.; Jackson, G.H.

    1999-03-01

    The transformation of 2,4,6-trinitrotoluene (TNT) was investigated in cultures of the cyanobacterium Anabaena sp. by conducting a series of batch assays. 2,4,6-Trinitrotoluene was added to Anabaena sp. cultures in single and consecutive additions, at various initial concentrations, to determine its transformation kinetics, to identify products formed, to evaluate potential toxicity, and to determine the effect of light deprivation on the TNT transformation process. 2,4,6-Trinitrotoluene disappearance occurred only in the presence of Anabaena sp. cultures maintained under a normal 16-h photoperiod. Toxicity leading to culture chlorosis and death was observed in batch systems with an initial TNT concentration greater than 10 mg/L. A low rate and extent of TNT disappearance was observed in light-deprived cultures, which were inhibited even at low TNT concentrations. At pH values between 7.5 and 8.5, azoxy-tetranitrotoluene isomers were detected in both the culture medium and solvent extracts of biomass and accounted for only 20 and 4.4% of the initially added TNT moles, respectively. At a culture pH range between 5.6 and 5.9, achieved by aeration with a 5% CO{sub 2}/air mixture, hydroxylaminodinitrotoluene equimolar to the TNT addition was produced and then depleted from the culture medium with prolonged incubation. Although TNT reduction in Anabaena sp. cultures occurred, yielding low levels of azoxy-tetranitrotoluene isomers or hydroxylaminodinitrotoluene, uptake and other transformation reactions of TNT and/or its transformation products by Anabaena sp. may have taken place. Based on a less than 15% observed increase of biomass concentration over the relatively short incubation periods and by considering the mean biomass concentration constant, the TNT disappearance rate followed pseudo-first-order kinetics. The biomass carbon-normalized TNT disappearance rates in Anabaena sp. cultures were about three orders of magnitude higher than previously reported TNT

  4. Integrating Health and Sustainability: The Higher Education Sector as a Timely Catalyst

    ERIC Educational Resources Information Center

    Orme, J.; Dooris, M.

    2010-01-01

    Higher education is an influential sector with enormous potential to impact positively on health and sustainability. The purpose of this paper was to explore its emergent role as a key setting for promoting health and sustainability and for addressing their challenges in an integrated and coherent way. Acknowledging both the relative narrowness of…

  5. Rural Education: A Field of Study Whose Time Has Come in Higher Education.

    ERIC Educational Resources Information Center

    Warner, Richard W., Jr.; Kale, Karen E.

    Although professional educators and public school decision makers have attempted to respond to increased educational demands and a broader spectrum of students, the education of rural youth is a neglected area both in higher education and in educational legislation. The record indicates that policy decisions and the resulting legislation have…

  6. The Effective Academic: A Handbook for Enhanced Academic Practice. The Times Higher Education Supplement.

    ERIC Educational Resources Information Center

    Ketteridge, Steve, Ed.; Marshall, Stephanie, Ed.; Fry, Heather, Ed.

    This handbook provides guidance about controlling and directing an academic career by suggesting systematic approaches to key areas of responsibility and activity. It explores management and leadership in higher education, developing and promoting research and teaching, and coping with the changing university environment. The chapters of part 1,…

  7. Challenges to Christian Higher Education at a Time of Increasing Emphasis on Research

    ERIC Educational Resources Information Center

    Hemmings, Brian; Hill, Doug

    2014-01-01

    In Australia, both Christian and non-Christian higher education institutions (HEIs) have experienced a rapidly changing external environment that is becoming more performance-driven, particularly in relation to faculty research. Academics working in Australian Christian HEIs often feel pressure to keep pace with their counterparts in non-Christian…

  8. Higher Education in a Dangerous Time: Will Technology Really Improve the University?

    ERIC Educational Resources Information Center

    Mahoney, John

    1998-01-01

    States that cost-control and efficiency initiatives will continue to be directed at higher education. Suggests that rather than focusing on technology it might be wiser to focus on attaining the highest standards in teaching, innovative learning opportunities, academic advising, and student-development services throughout the nation's colleges and…

  9. The Challenge and Promise of Catholic Higher Education for Our Time

    ERIC Educational Resources Information Center

    Jenkins, John I.

    2015-01-01

    Catholic colleges and universities face significant challenges in the present context of American higher education. Yet, there are opportunities to be found in the midst of this crisis when one carefully examines the intersections between the Catholic mission and objectives of an institution and current culture and academia. A return to the…

  10. Time-harmonic elasticity with controllability and higher-order discretization methods

    NASA Astrophysics Data System (ADS)

    Mönkölä, Sanna; Heikkola, Erkki; Pennanen, Anssi; Rossi, Tuomo

    2008-05-01

    The time-harmonic solution of the linear elastic wave equation is needed for a variety of applications. The typical procedure for solving the time-harmonic elastic wave equation leads to difficulties solving large-scale indefinite linear systems. To avoid these difficulties, we consider the original time dependent equation with a method based on an exact controllability formulation. The main idea of this approach is to find initial conditions such that after one time-period, the solution and its time derivative coincide with the initial conditions. The wave equation is discretized in the space domain with spectral elements. The degrees of freedom associated with the basis functions are situated at the Gauss-Lobatto quadrature points of the elements, and the Gauss-Lobatto quadrature rule is used so that the mass matrix becomes diagonal. This method is combined with the second-order central finite difference or the fourth-order Runge-Kutta time discretization. As a consequence of these choices, only matrix-vector products are needed in time dependent simulation. This makes the controllability method computationally efficient.

  11. Integrating health and sustainability: the higher education sector as a timely catalyst.

    PubMed

    Orme, J; Dooris, M

    2010-06-01

    Higher education is an influential sector with enormous potential to impact positively on health and sustainability. The purpose of this paper was to explore its emergent role as a key setting for promoting health and sustainability and for addressing their challenges in an integrated and coherent way. Acknowledging both the relative narrowness of the environmental focus that has to date characterized and driven universities' work in relation to sustainability and the demonstrable value of adopting a whole-system approach, this paper will explore the concept of 'Healthy Universities' as a means of furthering debate and facilitating synergy between public health, sustainable development and climate change. Higher education represents one large-scale sector with a unique combination of roles that can be harnessed to focus and mobilize its education, knowledge exchange, research, corporate responsibility and future shaping agendas to achieve significant impacts in this area. It is the growing commitment to embedding health and well-being within the mainstream business of higher education coupled with the expectation that universities will act sustainably in all that they do that provides the perfect springboard to influence a process of 'co-ordinated action' to address climate change and impact positively on the integrated health and sustainability agenda.

  12. Higher Dimensional Clayton–Oakes Models for Multivariate Failure Time Data

    PubMed Central

    Prentice, R. L.

    2016-01-01

    Summary The Clayton–Oakes bivariate failure time model is extended to dimensions m > 2 in a manner that allows unspecified marginal survivor functions for all dimensions less than m. Special cases that allow unspecified marginal survivor functions of dimension q with q < m, while making some provisions for dependencies of dimension greater than q, are also described. PMID:27738350

  13. Transformation or Decline? Using Tough Times to Create Higher-Performing Schools

    ERIC Educational Resources Information Center

    Miles, Karen Hawley

    2011-01-01

    Instead of doing less with less during these fiscally challenging times, school districts can seize the moment to usher in school transformation that will leave the schools, families, and communities better off. They could follow the lead of districts such as Baltimore City, Syracuse, and Charlotte-Mecklenburg to think outside traditional cost…

  14. Spanish Zimbardo Time Perspective Inventory Construction and Validity among Higher Education Students

    ERIC Educational Resources Information Center

    Usart, Mireia; Romero, Margarida

    2014-01-01

    Introduction: The study of "Time Orientation" (TO) has been focused on how to measure this construct and its effects on human behavior. Defined as a fundamental psychological variable, TO is multidimensional, sensible to cultural differences and age. Although its relation to learning, it deserves further study in the different Higher…

  15. Higher Prevalence of Left-Handedness in Twins? Not After Controlling Birth Time Confounders.

    PubMed

    Heikkilä, Kauko; Vuoksimaa, Eero; Saari-Kemppainen, Aulikki; Kaprio, Jaakko; Rose, Richard J; Haukka, Jari; Pitkäniemi, Janne; Iivanainen, Matti

    2015-10-01

    Pregnancy- and birth-related factors may have an effect on handedness. Compared with singletons, twins have a lower birth weight, shorter gestational age, and are at higher risk for birth complications. We tested whether the prevalence of left-handedness is higher among twins than singletons, and if so, whether that difference is fully explained by pregnancy and birth-related differences between twins and singletons. We analyzed Finnish population-based datasets; included were 8,786 twins and 5,892 singletons with information on birth weight (n = 12,381), Apgar scores (n = 11,129), and gestational age (n = 11,811). Two twin cohorts were involved: FinnTwin12 included twins born during 1983-1987, and FinnTwin16 included twins born during 1974-1979. We had two comparison groups of singletons: 4,101 individuals born during 1986-1988 and enrolled in the Helsinki Ultrasound Trial, and 1,791 individuals who were partners of FinnTwin16 twins. We used logistic regression models with writing hand as the outcome for comparison and evaluating effects of covariates. Left-handedness was more common in twins (9.67%) than in singletons (8.27%; p = .004). However, Apgar scores were associated with handedness, and after controlling for covariates, we found no difference in the prevalence of left-handedness between twins and singletons. Increased left-handedness among twins, often reported by others, was evident in our data, but only among our older twin cohorts, and that association disappeared after removing effects of perinatal covariates.

  16. Tensor-product preconditioners for higher-order space-time discontinuous Galerkin methods

    NASA Astrophysics Data System (ADS)

    Diosady, Laslo T.; Murman, Scott M.

    2017-02-01

    A space-time discontinuous-Galerkin spectral-element discretization is presented for direct numerical simulation of the compressible Navier-Stokes equations. An efficient solution technique based on a matrix-free Newton-Krylov method is developed in order to overcome the stiffness associated with high solution order. The use of tensor-product basis functions is key to maintaining efficiency at high-order. Efficient preconditioning methods are presented which can take advantage of the tensor-product formulation. A diagonalized Alternating-Direction-Implicit (ADI) scheme is extended to the space-time discontinuous Galerkin discretization. A new preconditioner for the compressible Euler/Navier-Stokes equations based on the fast-diagonalization method is also presented. Numerical results demonstrate the effectiveness of these preconditioners for the direct numerical simulation of subsonic turbulent flows.

  17. Higher-order hybrid implicit/explicit FDTD time-stepping

    NASA Astrophysics Data System (ADS)

    Tierens, W.

    2016-12-01

    Both partially implicit FDTD methods, and symplectic FDTD methods of high temporal accuracy (3rd or 4th order), are well documented in the literature. In this paper we combine them: we construct a conservative FDTD method which is fourth order accurate in time and is partially implicit. We show that the stability condition for this method depends exclusively on the explicit part, which makes it suitable for use in e.g. modelling wave propagation in plasmas.

  18. Visual detection of 2,4,6-trinitrotolune by molecularly imprinted colloidal array photonic crystal.

    PubMed

    Lu, Wei; Asher, Sanford A; Meng, Zihui; Yan, Zequn; Xue, Min; Qiu, Lili; Yi, Da

    2016-10-05

    We developed a photonic crystal (PhC) sensor for the quantification of 2,4,6-trinitrotoluene (TNT) in solution. Monodisperse (210nm in diameter) molecularly imprinted colloidal particles (MICs) for TNT were prepared by the emulsion polymerization of methyl methacrylate and acrylamide in the presence of TNT as a template. The MICs were then self-assembled into close-packed opal PhC films. The adsorption capacity of the MICs for TNT was 64mg TNT/g. The diffraction from the PhC depended on the TNT concentration in a methanol/water (3/2, v/v) potassium dihydrogen phosphate buffer solution (pH=7.0, 30mM). The limit of detection (LOD) of the sensor was 1.03μg. The color of the molecularly imprinted colloidal array (MICA) changed from green to red with an 84nm diffraction red shift when the TNT concentration increased to 20mM. The sensor response time was 3min. The PhC sensor was selective for TNT compared to similar compounds such as 2,4,6-trinitrophenol, 2,4-dinitrotoluene, 2,6-dinitrotoluene, 2-nitromesitylene, 4-nitrotoluene, 2-nitrotoluene, 1,3-dinitrobenzene, methylbenzene, 4-nitrophenol, 2-nitroaniline, 3-aminophenol and 3-nitroaniline. The sensor showed high stability with little response change after three years storage. This sensor technology might be useful for the visual determination of TNT.

  19. BIOTRANSFORMATION OF 2,4,6-TRINITROTOLUENE IN A CONTINUOUS-FLOW ANABAENA SP. SYSTEM. (R825513C013)

    EPA Science Inventory

    Reductive transformation of 2,4,6-trinitrotoluene (TNT) was observed in a continuous-flow system of Anabaena sp. operated for 33 d with a 5.7 d hydraulic retention time and a range of influent TNT concentrations of 1–58 mg/l. The TNT removal effici...

  20. Higher-Pressure Ion Funnel Trap Interface for Orthogonal Time-of-Flight Mass Spectrometry

    PubMed Central

    Ibrahim, Yehia; Belov, Mikhail E.; Tolmachev, Aleksey V.; Prior, David C.; Smith, Richard D.

    2008-01-01

    A combined electrodynamic ion funnel and ion trap coupled to an orthogonal acceleration (oa)-time-of-flight mass spectrometer (oa-TOF MS) was developed and characterized. The ion trap was incorporated through the use of added terminal electrodynamic ion funnel electrodes enabling control over the axial DC gradient in the trap section. The ion trap operates efficiently at a pressure of 1 Torr, and measurements indicate a maximum charge capacity of ~3×107 charges. An order of magnitude increase in sensitivity was observed in the analysis of low concentration peptides mixtures with oa-TOF MS in the trapping mode as compared to the continuous regime. A signal increase in the trapping mode was accompanied by reduction in the background chemical noise, due to more efficient desolvation of e.g., solvent related clusters. Controlling the ion trap ejection time was found to result in efficient removal of singly charged species and improving signal-to-noise ratio (S/N) for the multiply charged analytes. PMID:17850113

  1. Modern U-Pb chronometry of meteorites: advancing to higher time resolution reveals new problems

    USGS Publications Warehouse

    Amelin, Y.; Connelly, J.; Zartman, R.E.; Chen, J.-H.; Gopel, C.; Neymark, L.A.

    2009-01-01

    In this paper, we evaluate the factors that influence the accuracy of lead (Pb)-isotopic ages of meteorites, and may possibly be responsible for inconsistencies between Pb-isotopic and extinct nuclide timescales of the early Solar System: instrumental mass fractionation and other possible analytical sources of error, presence of more than one component of non-radiogenic Pb, migration of ancient radiogenic Pb by diffusion and other mechanisms, possible heterogeneity of the isotopic composition of uranium (U), uncertainties in the decay constants of uranium isotopes, possible presence of "freshly synthesized" actinides with short half-life (e.g. 234U) in the early Solar System, possible initial disequilibrium in the uranium decay chains, and potential fractionation of radiogenic Pb isotopes and U isotopes caused by alpha-recoil and subsequent laboratory treatment. We review the use of 232Th/238U values to assist in making accurate interpretations of the U-Pb ages of meteorite components. We discuss recently published U-Pb dates of calcium-aluminum-rich inclusions (CAIs), and their apparent disagreement with the extinct nuclide dates, in the context of capability and common pitfalls in modern meteorite chronology. Finally, we discuss the requirements of meteorites that are intended to be used as the reference points in building a consistent time scale of the early Solar System, based on the combined use of the U-Pb system and extinct nuclide chronometers.

  2. A generative spike train model with time-structured higher order correlations.

    PubMed

    Trousdale, James; Hu, Yu; Shea-Brown, Eric; Josić, Krešimir

    2013-01-01

    Emerging technologies are revealing the spiking activity in ever larger neural ensembles. Frequently, this spiking is far from independent, with correlations in the spike times of different cells. Understanding how such correlations impact the dynamics and function of neural ensembles remains an important open problem. Here we describe a new, generative model for correlated spike trains that can exhibit many of the features observed in data. Extending prior work in mathematical finance, this generalized thinning and shift (GTaS) model creates marginally Poisson spike trains with diverse temporal correlation structures. We give several examples which highlight the model's flexibility and utility. For instance, we use it to examine how a neural network responds to highly structured patterns of inputs. We then show that the GTaS model is analytically tractable, and derive cumulant densities of all orders in terms of model parameters. The GTaS framework can therefore be an important tool in the experimental and theoretical exploration of neural dynamics.

  3. Accuracy of rate coding: When shorter time window and higher spontaneous activity help

    NASA Astrophysics Data System (ADS)

    Levakova, Marie; Tamborrino, Massimiliano; Kostal, Lubomir; Lansky, Petr

    2017-02-01

    It is widely accepted that neuronal firing rates contain a significant amount of information about the stimulus intensity. Nevertheless, theoretical studies on the coding accuracy inferred from the exact spike counting distributions are rare. We present an analysis based on the number of observed spikes assuming the stochastic perfect integrate-and-fire model with a change point, representing the stimulus onset, for which we calculate the corresponding Fisher information to investigate the accuracy of rate coding. We analyze the effect of changing the duration of the time window and the influence of several parameters of the model, in particular the level of the presynaptic spontaneous activity and the level of random fluctuation of the membrane potential, which can be interpreted as noise of the system. The results show that the Fisher information is nonmonotonic with respect to the length of the observation period. This counterintuitive result is caused by the discrete nature of the count of spikes. We observe also that the signal can be enhanced by noise, since the Fisher information is nonmonotonic with respect to the level of spontaneous activity and, in some cases, also with respect to the level of fluctuation of the membrane potential.

  4. A generative spike train model with time-structured higher order correlations

    PubMed Central

    Trousdale, James; Hu, Yu; Shea-Brown, Eric; Josić, Krešimir

    2013-01-01

    Emerging technologies are revealing the spiking activity in ever larger neural ensembles. Frequently, this spiking is far from independent, with correlations in the spike times of different cells. Understanding how such correlations impact the dynamics and function of neural ensembles remains an important open problem. Here we describe a new, generative model for correlated spike trains that can exhibit many of the features observed in data. Extending prior work in mathematical finance, this generalized thinning and shift (GTaS) model creates marginally Poisson spike trains with diverse temporal correlation structures. We give several examples which highlight the model's flexibility and utility. For instance, we use it to examine how a neural network responds to highly structured patterns of inputs. We then show that the GTaS model is analytically tractable, and derive cumulant densities of all orders in terms of model parameters. The GTaS framework can therefore be an important tool in the experimental and theoretical exploration of neural dynamics. PMID:23908626

  5. Space and time diversity in indoor wireless optical links achieving higher data rate

    NASA Astrophysics Data System (ADS)

    Alqudah, Yazan A.

    2013-02-01

    Multispot diffusing configuration (MSDC) in optical wireless links provide uniform optical power needed for multiaccess and spatial dependence that can be used to allow space diversity techniques over the link. The spatial channels are furnished in MSDC through utilizing multibeam transmitter that produces spatially confined diffusing spots, and a multibranch receiver with small enough branch field-of-view (FOV) to restrict the number of diffusing spots within its FOV. Here, we study different encoding techniques that use space and time diversity to reduce the bit error rate. An improved technique, constellation rotation, is proposed for pulse amplitude modulated (PAM) to increase the Euclidian distance between signal points, and thus reduce bit error. Our study shows that when a cap is placed on the amount of power allocated per channel, the performance of the improved 4-PAM using three spatial channels and soft binary decision provide the optimal performance. When the power allocated per user is restricted, the best performance is obtained through soft binary decision and by using symbols identified by their level and spatial channel to carry 2 bits per signal level-channel.

  6. Impact of the Headscarf Ban Policy on the Identity Development of Part-Time Unveilers in Turkish Higher Education

    ERIC Educational Resources Information Center

    Seggie, Fatma Nevra; Austin, Ann E.

    2010-01-01

    This qualitative study examines the impact of the Turkish higher education headscarf ban policy on the plural self-identities (i.e., as Turkish citizens, as Muslims, and as females) of part-time unveilers, female students who cover their hair in their private life but who remove the headscarf (or conceal it to appear unveiled) while at a Turkish…

  7. Utilizing Social Networks in Times of Crisis: Understanding, Exploring and Analyzing Critical Incident Management at Institutions of Higher Education

    ERIC Educational Resources Information Center

    Asselin, Martha Jo

    2012-01-01

    With the rising number of major crises on college campuses today (Security on Campus Inc., 2009), institutions of higher education can benefit from understanding of how social networks may be used in times of emergency. What is currently known about the usage of social networks is not integral to the current practices of crisis management that are…

  8. The Transition from Higher Education to Employment in Europe: The Analysis of the Time to Obtain the First Job

    ERIC Educational Resources Information Center

    Salas-Velasco, Manuel

    2007-01-01

    This paper investigates the determinants of the transition from higher education to work across Europe using various specifications of duration models and a one-time multi-country survey of university graduates from nine European countries. Results point to differences between the North and South of Europe in the difficulty of getting a first job.…

  9. Cooperative Weblog Learning in Higher Education: Its Facilitating Effects on Social Interaction, Time Lag, and Cognitive Load

    ERIC Educational Resources Information Center

    Huang, Tien-Chi; Huang, Yueh-Min; Yu, Fu-Yun

    2011-01-01

    This paper examines the effects of using weblog technologies to support cooperative learning in higher education. The study focused on the effects of features embedded in weblogs on social interactions, time lags, and cognitive loads. A quasi-experimental control-group research design was adopted. The participants were 115 undergraduates who were…

  10. Assessment of a 2,4,6-trinitrotoluene-contaminated site using Aporrectodea rosea and Eisenia andrei in mesocosms.

    PubMed

    Robidoux, P Y; Svendsen, C; Sarrazin, M; Thiboutot, S; Ampleman, G; Hawari, J; Weeks, J M; Sunahara, G I

    2005-01-01

    Polynitro-organic compounds such as 2,4,6-trinitrotoluene (TNT) can be released into the environment from production and processing facilities and military firing ranges as well as through field use and disposal practices. Based on laboratory toxicity data, TNT has lethal (at >/=260 mg TNT/kg dry soil) and sublethal effects (at >/=59 mg TNT/kg dry soil) to the earthworm. However, field studies are needed to relate exposure of organisms to explosives in mixed-contaminated soil under field conditions and to define effects-based ecotoxicologic benchmarks for TNT-contaminated soil. In the present study, the lethal and sublethal effects of a 10-day in situ exposure at a TNT-contaminated field site using mesh-bag mesocosms were assessed. In addition to the survival end point, the biomarkers of earthworm exposure and effect-including tissue residues, lysosomal neutral red retention time (NRRT), and total immune activity (TIA)-were measured. Concentrations of TNT in soil mesocosms ranged from 25 to 17,063 mg/kg. Experiments indicated a trend toward decreasing survival of caged Aporrectodea rosea and Eisenia andrei as the concentration of TNT and total nitroaromatic compounds increased. E. andrei tolerated higher concentrations of TNT (up to 4050 mg/kg dry soil) in mesocosms than did indigenous earthworms, who survived only at 4,6-dinitrotoluene and 4-amino-2,6-dinitrotoluene were not correlated with TNT soil concentrations. In addition, higher tissue concentrations of TNT metabolites were observed at concentrations ranging from 116 to 130 mg TNT/kg soil. The results showed that earthworm

  11. Adsorption of 4,6-dimethyldibenzothiophene and collidine over MoO3/γ-Al2O3 catalysts with different pore structures.

    PubMed

    Zhang, Di; Xue, Lijun; Xu, Yongqiang; Song, Lijuan; Liu, Xinmei

    2017-05-01

    Mesoporous γ-Al2O3 supports with different pore structures were prepared by the cation-anion double hydrolysis method. Based on these samples, MoO3/γ-Al2O3 catalysts were made via impregnation. The adsorptions of 4,6-dimethyldibenzothiophene (4,6-DMDBT) and collidine over the supports and catalysts were studied by FT-IR. The supports or catalysts with larger pores can adsorb more 4,6-DMDBT. The methyl groups on adsorbate molecules are very close to the sulfur atom, resulting in apparent steric hindrance. Increasing the pore size can promote the interaction between the adsorbates and supports or catalysts, enhancing the CC bond and weakening the CS bond of 4,6-DMDBT. 4,6-DMDBT molecules were coordinated with the unsaturated Mo atoms over the catalysts to form π-complexation adsorption. There was much difference between thiophene and 4,6-DMDBT adsorption. The adsorption of collidine over the catalysts also illustrated that there existed steric hindrance. Significantly, the catalyst with hierarchical mesopores was beneficial for the adsorbates with larger molecular dynamics diameter. Compared with the pore size, the specific surface area was not the key factor to affect the adsorptions of 4,6-DMDBT and collidine. The hydrodesulfurization reaction of 4,6-DMDBT illustrated that the catalysts with larger pore size or hierarchical pore structure presented higher desulfurization efficiency (above than 80%).

  12. 3D Visualization of Developmental Toxicity of 2,4,6-Trinitrotoluene in Zebrafish Embryogenesis Using Light-Sheet Microscopy

    PubMed Central

    Eum, Juneyong; Kwak, Jina; Kim, Hee Joung; Ki, Seoyoung; Lee, Kooyeon; Raslan, Ahmed A.; Park, Ok Kyu; Chowdhury, Md Ashraf Uddin; Her, Song; Kee, Yun; Kwon, Seung-Hae; Hwang, Byung Joon

    2016-01-01

    Environmental contamination by trinitrotoluene is of global concern due to its widespread use in military ordnance and commercial explosives. Despite known long-term persistence in groundwater and soil, the toxicological profile of trinitrotoluene and other explosive wastes have not been systematically measured using in vivo biological assays. Zebrafish embryos are ideal model vertebrates for high-throughput toxicity screening and live in vivo imaging due to their small size and transparency during embryogenesis. Here, we used Single Plane Illumination Microscopy (SPIM)/light sheet microscopy to assess the developmental toxicity of explosive-contaminated water in zebrafish embryos and report 2,4,6-trinitrotoluene-associated developmental abnormalities, including defects in heart formation and circulation, in 3D. Levels of apoptotic cell death were higher in the actively developing tissues of trinitrotoluene-treated embryos than controls. Live 3D imaging of heart tube development at cellular resolution by light-sheet microscopy revealed trinitrotoluene-associated cardiac toxicity, including hypoplastic heart chamber formation and cardiac looping defects, while the real time PCR (polymerase chain reaction) quantitatively measured the molecular changes in the heart and blood development supporting the developmental defects at the molecular level. Identification of cellular toxicity in zebrafish using the state-of-the-art 3D imaging system could form the basis of a sensitive biosensor for environmental contaminants and be further valued by combining it with molecular analysis. PMID:27869673

  13. Meeting Materials for the December 4-6, 2013 Scientific Advisory Panel

    EPA Pesticide Factsheets

    Meeting Materials for the December 4-6, 2013 Scientific Advisory Panel on Scientific Uncertainties Associated with Corn Rootworm Resistance Monitoring for Bt Corn Plant Incorporated Protectants (PIPs)

  14. Do CDK4/6 inhibitors have potential as targeted therapeutics for squamous cell cancers?

    PubMed

    Kalu, Nene N; Johnson, Faye M

    2017-02-01

    Introduction Dysregulation of cell cycle progression has an established link to neoplasia and cancer progression. Components of the cyclin D-CDK4/6-INK4-Rb pathway are frequently altered in squamous cell carcinomas (SCCs) by diverse mechanisms, including viral oncogene-induced degradation, mutation, deletion, and amplification. Activation of the CDK4/6 pathway may predict response to CDK4/6 inhibitors and provide clinical biomarkers. Recently, the CDK4/6 inhibitor palbociclib showed clinical efficacy in combination with cetuximab in HNSCC patients. Areas covered This review focuses on the current research on the use of CDK4/6 inhibitors, comprising preclinical animal studies through phase II clinical trials across all SCCs. Expert opinion CDK4/6 inhibitors have a proven clinical benefit in breast cancer, but data on SCCs are sparse. Although frequent dysregulation of the cyclin D-CDK4/6-INK4-Rb pathway in SCCs suggests that targeting CDK4/6 may hold promise for improved clinical outcomes, single-agent activity has been modest in preclinical studies and absent in clinical studies. Combinations with immunotherapy or inhibitors of the PI3 K/mTOR or EGFR pathway may be effective. Given that SCCs caused by human papillomavirus have high levels of p16 and low levels of Rb, the CDK4/6 inhibitors are predicted to be ineffective in these cancers.

  15. Comparison of Physical Examination and Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography 4-6 Months After Radiotherapy to Assess Residual Head-and-Neck Cancer

    SciTech Connect

    Zundel, M. Tracy; Michel, Michelle A.; Schultz, Christopher J.; Maheshwari, Mohit; Wong, Stuart J.; Campbell, Bruce H.; Massey, Becky L.; Blumin, Joel; Wilson, J. Frank; Wang, Dian

    2011-12-01

    Purpose: To retrospectively compare fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) and physical examination 4-6 months after radiotherapy for assessing residual head-and-neck cancer (HNC). Methods and Materials: From July 2002 through March 2006, 52 HNC patients underwent definitive radiotherapy or chemoradiotherapy. Categoric assessments of residual tumor by PET/CT and physical examination 4-6 months after therapy were correlated and compared with clinical outcomes. Pretreatment data, including tumor stage and primary site standardized uptake value, were also gathered retrospectively and correlated with clinical outcomes. Median follow-up time was 58 months. Results: Twenty-one patients had either locoregionally 'positive' (17 of 21) or 'equivocal' (4 of 21) PET/CT scans, whereas 31 patients had locoregionally negative scans. Four patients failed treatment and had biopsy-confirmed residual or recurrent local disease. All patients, including patients with locally suspicious scans or examinations who refused biopsies, were followed clinically for a minimum of 29 months after therapy, with no other cases of treatment failure detected during this time. No patient had residual nodal disease after therapy. Sensitivities of PET/CT vs. physical examination for early detection of treatment failure were 100% vs. 50%, whereas the specificities of the two modalities were 64.6% vs. 89.6%, respectively. Higher initial T stage and American Joint Commission on Cancer stage correlated with increased incidence of positive/equivocal PET/CT results and treatment failure. Maximal standardized uptake value was not predictive of any clinical outcome. Conclusions: A negative result on PET/CT obtained 4-6 months after radiotherapy is highly sensitive and correlates with successful locoregional control. Patients with negative scans may reasonably be spared invasive diagnostic procedures, such as biopsy and neck dissection, unless recurrent disease is suspected

  16. State-space analysis of time-varying higher-order spike correlation for multiple neural spike train data.

    PubMed

    Shimazaki, Hideaki; Amari, Shun-Ichi; Brown, Emery N; Grün, Sonja

    2012-01-01

    Precise spike coordination between the spiking activities of multiple neurons is suggested as an indication of coordinated network activity in active cell assemblies. Spike correlation analysis aims to identify such cooperative network activity by detecting excess spike synchrony in simultaneously recorded multiple neural spike sequences. Cooperative activity is expected to organize dynamically during behavior and cognition; therefore currently available analysis techniques must be extended to enable the estimation of multiple time-varying spike interactions between neurons simultaneously. In particular, new methods must take advantage of the simultaneous observations of multiple neurons by addressing their higher-order dependencies, which cannot be revealed by pairwise analyses alone. In this paper, we develop a method for estimating time-varying spike interactions by means of a state-space analysis. Discretized parallel spike sequences are modeled as multi-variate binary processes using a log-linear model that provides a well-defined measure of higher-order spike correlation in an information geometry framework. We construct a recursive Bayesian filter/smoother for the extraction of spike interaction parameters. This method can simultaneously estimate the dynamic pairwise spike interactions of multiple single neurons, thereby extending the Ising/spin-glass model analysis of multiple neural spike train data to a nonstationary analysis. Furthermore, the method can estimate dynamic higher-order spike interactions. To validate the inclusion of the higher-order terms in the model, we construct an approximation method to assess the goodness-of-fit to spike data. In addition, we formulate a test method for the presence of higher-order spike correlation even in nonstationary spike data, e.g., data from awake behaving animals. The utility of the proposed methods is tested using simulated spike data with known underlying correlation dynamics. Finally, we apply the methods

  17. DNA replication timing and higher-order nuclear organization determine single-nucleotide substitution patterns in cancer genomes.

    PubMed

    Liu, Lin; De, Subhajyoti; Michor, Franziska

    2013-01-01

    Single-nucleotide substitutions are a defining characteristic of cancer genomes. Many single-nucleotide substitutions in cancer genomes arise because of errors in DNA replication, which is spatio-temporally stratified. Here we propose that DNA replication patterns help shape the mutational landscapes of normal and cancer genomes. Using data on five fully sequenced cancer types and two personal genomes, we determined that the frequency of intergenic single-nucleotide substitution is significantly higher in late DNA replication timing regions, even after controlling for a number of genomic features. Furthermore, some substitution signatures are more frequent in certain DNA replication timing zones. Finally, integrating data on higher-order nuclear organization, we found that genomic regions in close spatial proximity to late-replicating domains display similar mutation spectra as the late-replicating regions themselves. These data suggest that DNA replication timing together with higher-order genomic organization contribute to the patterns of single-nucleotide substitution in normal and cancer genomes.

  18. 45 CFR 4.6 - Materials related to petitions under the National Vaccine Injury Compensation Program.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Vaccine Injury Compensation Program. 4.6 Section 4.6 Public Welfare DEPARTMENT OF HEALTH AND HUMAN... Vaccine Injury Compensation Program. Notwithstanding the provisions of §§ 4.1, 4.2, and 4.3, service of..., shall be served upon the Director, Division of Vaccine Injury Compensation, Office of Special...

  19. 45 CFR 4.6 - Materials related to petitions under the National Vaccine Injury Compensation Program.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Vaccine Injury Compensation Program. 4.6 Section 4.6 Public Welfare Department of Health and Human... Vaccine Injury Compensation Program. Notwithstanding the provisions of §§ 4.1, 4.2, and 4.3, service of..., shall be served upon the Director, Division of Vaccine Injury Compensation, Office of Special...

  20. 45 CFR 4.6 - Materials related to petitions under the National Vaccine Injury Compensation Program.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Vaccine Injury Compensation Program. 4.6 Section 4.6 Public Welfare DEPARTMENT OF HEALTH AND HUMAN... Vaccine Injury Compensation Program. Notwithstanding the provisions of §§ 4.1, 4.2, and 4.3, service of..., shall be served upon the Director, Division of Vaccine Injury Compensation, Office of Special...

  1. 45 CFR 4.6 - Materials related to petitions under the National Vaccine Injury Compensation Program.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Vaccine Injury Compensation Program. 4.6 Section 4.6 Public Welfare DEPARTMENT OF HEALTH AND HUMAN... Vaccine Injury Compensation Program. Notwithstanding the provisions of §§ 4.1, 4.2, and 4.3, service of..., shall be served upon the Director, Division of Vaccine Injury Compensation, Office of Special...

  2. 45 CFR 4.6 - Materials related to petitions under the National Vaccine Injury Compensation Program.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Vaccine Injury Compensation Program. 4.6 Section 4.6 Public Welfare DEPARTMENT OF HEALTH AND HUMAN... Vaccine Injury Compensation Program. Notwithstanding the provisions of §§ 4.1, 4.2, and 4.3, service of..., shall be served upon the Director, Division of Vaccine Injury Compensation, Office of Special...

  3. 43 CFR 1610.4-6 - Estimation of effects of alternatives.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Estimation of effects of alternatives. 1610.4-6 Section 1610.4-6 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR GENERAL MANAGEMENT (1000) PLANNING,...

  4. Function of the Golgi-located phosphate transporter PHT4;6 is critical for senescence-associated processes in Arabidopsis

    PubMed Central

    Hassler, Sebastian; Jung, Benjamin; Lemke, Lilia; Novák, Ondřej; Strnad, Miroslav; Martinoia, Enrico; Neuhaus, H. Ekkehard

    2016-01-01

    The phosphate transporter PHT4;6 locates to the trans-Golgi compartment, and its impaired activity causes altered intracellular phosphate compartmentation, leading to low cytosolic Pi levels, a blockage of Golgi-related processes such as protein glycosylation and hemicellulose biosynthesis, and a dwarf phenotype. However, it was unclear whether altered Pi homeostasis in pht4;6 mutants causes further cellular problems, typically associated with limited phosphate availability. Here we report that pht4;6 mutants exhibit a markedly increased disposition to induce dark-induced senescence. In control experiments, in which pht4;6 mutants and wild-type plants developed similarly, we confirmed that accelerated dark-induced senescence in mutants is not a ‘pleiotropic’ process associated with the dwarf phenotype. In fact, accelerated dark-induced senescence in pht4;6 mutants correlates strongly with increased levels of toxic NH4 + and higher sensitivity to ammonium, which probably contribute to the inability of pht4;6 mutants to recover from dark treatment. Experiments with modified levels of either salicylic acid (SA) or trans-zeatin (tZ) demonstrate that altered concentrations of these compounds in pht4;6 plants act as major cellular mediators for dark-induced senescence. This conclusion gained further support from the notion that the expression of the pht4;6 gene is, in contrast to genes coding for major phosphate importers, substantially induced by tZ. Taken together, our findings point to a critical function of PHT4;6 to control cellular phosphate levels, in particular the cytosolic Pi availability, required to energize plant primary metabolism for proper plant development. Phosphate and its allocation mediated by PHT4;6 is critical to prevent onset of dark-induced senescence. PMID:27325894

  5. [Characteristics and mechanism of 2,4,6-TCP degradation by the "Fe0/enriched-bacteria" system].

    PubMed

    Dai, You-zhi; Guo, Li-li; Shi, Lei; Liu, Zhi-yong; Gao, Bao-chai

    2012-08-01

    The synergistic mechanism of 2, 4, 6-trichlorophenol (TCP) degradation using a combination of Fe0 and anaerobic dechlorinating bacteria with batch processing was investigated. Experimental results showed that under the conditions of pH 7.0, Fe0 5 g x L(-1) and 2,4,6-TCP 30 mg x L(-1), the growth and interface enrichment of enriched-bacteria could be promoted by Fe0, the cell mass (expressed by D600) of Fe0/enriched-bacteria was about 1.7 times as high as that of the individual predominant groups of dechlorinating bacteria. After 96 h reaction, large amount of bacteria attached to the iron surface, with short rod or coccus-like morphology. The pH value of the system was maintained at 7.8, which could be beneficial to the reductive dechlorination reaction and the growth of the enriched-bacteria. The major pathway of 2,4,6-TCP degradation in the Fe0/enriched-bacteria system was 2,4,6-TCP to 2,4-DCP and then to 4-CP.

  6. Is the general conclusion justified that higher applicable field strength results in shorter analysis time with organic solvents in CE?

    PubMed

    Téllez, Adolfo; Kenndler, Ernst

    2009-11-01

    In this paper, a widespread opinion in CE with organic solvents for the background electrolyte is critically questioned, namely that in general a shorter analysis time can be achieved due to the higher field strength applicable compared with aqueous electrolyte systems. This view, common in the literature, is based on the supposition that the conductance in organic solvents is lower than in water. Indeed in many organic solvents with higher viscosity than water lower ion mobility is observed, and higher fields can be applied in these cases. However, in this paper the problem is sharper defined and treated two-fold: (i) in all solvents conditions are such that either the same electric power is generated, or (ii) the same temperature increase is taken into account. It was shown that for the same electric power the field strength in the organic solvent can be changed to a less extent than the ionic mobility changes. As a result, the migration velocity of the analytes is lower and the analysis time is longer in most organic solvents compared with water; acetonitrile (MeCN) is an exception (in this solvent the mobilities are higher than in water). The more stringent treatment of the problem takes an equal temperature increase due to Joule heating into account rather than equal electric power. The temperature increase in the capillary depends on the thermal conductivity of the solvent, which is only about one-third of that of water for organic liquids. The consequence is that in none of the organic solvent systems a shorter analysis time can be achieved compared with water (given that the experimental conditions are comparable, e.g. zero EOF). The theoretical predictions were confirmed by measurements with water, methanol, propylenecarbonate, and MeCN as solvents.

  7. A High-Order, Linear Time-Invariant Model for Application to Higher Harmonic Control and Flight Control System Interaction

    NASA Technical Reports Server (NTRS)

    Cheng, Rendy P.; Tischler, Mark B.; Celi, Roberto

    2006-01-01

    This research describes a new methodology for the extraction of a high-order, linear time invariant model, which allows the periodicity of the helicopter response to be accurately captured. This model provides the needed level of dynamic fidelity to permit an analysis and optimization of the AFCS and HHC algorithms. The key results of this study indicate that the closed-loop HHC system has little influence on the AFCS or on the vehicle handling qualities, which indicates that the AFCS does not need modification to work with the HHC system. However, the results show that the vibration response to maneuvers must be considered during the HHC design process, and this leads to much higher required HHC loop crossover frequencies. This research also demonstrates that the transient vibration responses during maneuvers can be reduced by optimizing the closed-loop higher harmonic control algorithm using conventional control system analyses.

  8. Induction of apoptosis of 2,4',6-trihydroxybenzophenone in HT-29 colon carcinoma cell line.

    PubMed

    Lay, Ma Ma; Karsani, Saiful Anuar; Malek, Sri Nurestri Abd

    2014-01-01

    2,4',6-Trihydroxy-4-methoxybenzophenone was isolated from the ethyl acetate fraction of Phaleria macrocarpa (Scheff.) Boerl. fruits. It was found to inhibit cell proliferation in HT-29 human colon carcinoma cell line but caused little damage to WRL-68 normal human liver and MRC-5 normal human fibroblast lung cell lines. The compound was found to sharply affect the viability of HT-29 cells in a dose- and time-dependent manner. HT-29 cells treated with the compound showed morphological changes under microscopic examination such as cell shrinkage, membrane blebbing, DNA fragmentation, and the occurrence of apoptotic nuclei. The percentage of early apoptotic, late apoptotic, and dead or necrotic cells was determined by flow cytometry using annexin V-FTIC/PI staining. In addition, flow cytometry showed that, when the HT-29 cells were treated with 115 µM of the compound, it resulted in G0/G1 phase arrest in a time-dependent manner. Western blot revealed an upregulation of PUMA, Bak, Bcl-2, and Mcl-1 proteins suggesting that the compound induced apoptosis in HT-29 cells by regulating these proteins.

  9. Penta- and 2,4,6-tri-chlorophenol biodegradation during municipal solid waste anaerobic digestion.

    PubMed

    Limam, Intissar; Limam, Rim Driss; Mezni, Mohamed; Guenne, Angéline; Madigou, Céline; Driss, Mohamed Ridha; Bouchez, Théodore; Mazeas, Laurent

    2016-08-01

    In this study isotopic tracing using (13)C labelled pentachlorophenol (PCP) and 2,4,6-trichlorophenol (2,4,6-TCP) is proposed as a tool to distinguish the loss of PCP and 2,4,6-TCP due to biodegradation from other physical processes. This isotopic approach was applied to accurately assess in situ PCP and 2,4,6-TCP degradation under methanogenic conditions in several microcosms made up of household waste. These microcosms were incubated in anaerobic conditions at 35°C (mesophilic) and 55°C (thermophilic) without agitation. The volume of biogas produced (CH4 and CO2), was followed for a period of 130 days. At this stage of stable methanogenesis, (13)C6-PCP and (13)C6-2,4,6-TCP were introduced anaerobically in microcosms and its monitoring at mesophilic and thermophilic conditions was performed in parallel by gas chromatography mass spectrometry (GC-MS) and gas chromatography isotope-ratio mass spectrometry (GC-IRMS). This study proved the almost total dechlorination of bioavailable PCP and 2,4,6-TCP into 4-CP at 35°C. Nevertheless, high rate adsorption in particular materials of the two compounds was observed. Furthermore, Carbon-13 Nuclear Magnetic Resonance ((13)C-NMR) Spectroscopy analysis of (13)C labelled 2,4,6-TCP mesophilic incubations showed the partial mineralization of 4-CP at 35°C to acetate and then to HCO(3-). Consequently, NMR results confirm the biogas isotopic results indicating the mineralization of (13)C labelled 2,4,6-TCP into (13)C (CH4 and CO2). Concerning (13)C labelled PCP mesophilic incubations, the isotopic composition of the biogas still natural until the day 262. In contrast, no dechlorination was observed at 55°C. Thus PCP and 2,4,6-TCP were persistent in thermophilic conditions.

  10. Age of Complementary Foods Introduction and Risk of Anemia in Children Aged 4-6 years: A Prospective Birth Cohort in China.

    PubMed

    Wang, Fenglei; Liu, Huijuan; Wan, Yi; Li, Jing; Chen, Yu; Zheng, Jusheng; Huang, Tao; Li, Duo

    2017-03-23

    Age of complementary foods introduction is associated with childhood anemia, but the ideal age for the introduction of complementary foods to infants is a continuing topic of debate. We examined the longitudinal association between complementary foods introduction age and risk of anemia in 18,446 children from the Jiaxing Birth Cohort, who had detailed complementary feeding records at 3 and 6 months of age and had hemoglobin concentrations measured at 4-6 years. Early introduction of complementary foods at 3-6 months of age was significantly associated with a higher risk of anemia (odds ratio = 1.14; 95% confidence interval: 1.01-1.28) and a lower hemoglobin concentration of -0.84 g/L (95% confidence interval: -1.33 to -0.35) in children aged 4-6 years, compared with those fed complementary foods starting at 6 months of age. When it comes to the specific type of complementary foods, early introduction of all plant-based foods was associated with increased anemia risks and lower hemoglobin concentrations, while early introduction of most animal-based foods was not. These findings may be informative regarding the appropriate time to introduce complementary foods in infants.

  11. Less Time to Study, Less Well Prepared for Work, yet Satisfied with Higher Education: A UK Perspective on Links between Higher Education and the Labour Market

    ERIC Educational Resources Information Center

    Little, Brenda; Arthur, Lore

    2010-01-01

    This paper explores graduates' views on the relationship between higher education and employment. It draws on a major European study involving graduates five years after graduation and highlights similarities and differences between UK graduates' experiences and their European counterparts. Specifically, we address questions raised in the study…

  12. State-Space Analysis of Time-Varying Higher-Order Spike Correlation for Multiple Neural Spike Train Data

    PubMed Central

    Shimazaki, Hideaki; Amari, Shun-ichi; Brown, Emery N.; Grün, Sonja

    2012-01-01

    Precise spike coordination between the spiking activities of multiple neurons is suggested as an indication of coordinated network activity in active cell assemblies. Spike correlation analysis aims to identify such cooperative network activity by detecting excess spike synchrony in simultaneously recorded multiple neural spike sequences. Cooperative activity is expected to organize dynamically during behavior and cognition; therefore currently available analysis techniques must be extended to enable the estimation of multiple time-varying spike interactions between neurons simultaneously. In particular, new methods must take advantage of the simultaneous observations of multiple neurons by addressing their higher-order dependencies, which cannot be revealed by pairwise analyses alone. In this paper, we develop a method for estimating time-varying spike interactions by means of a state-space analysis. Discretized parallel spike sequences are modeled as multi-variate binary processes using a log-linear model that provides a well-defined measure of higher-order spike correlation in an information geometry framework. We construct a recursive Bayesian filter/smoother for the extraction of spike interaction parameters. This method can simultaneously estimate the dynamic pairwise spike interactions of multiple single neurons, thereby extending the Ising/spin-glass model analysis of multiple neural spike train data to a nonstationary analysis. Furthermore, the method can estimate dynamic higher-order spike interactions. To validate the inclusion of the higher-order terms in the model, we construct an approximation method to assess the goodness-of-fit to spike data. In addition, we formulate a test method for the presence of higher-order spike correlation even in nonstationary spike data, e.g., data from awake behaving animals. The utility of the proposed methods is tested using simulated spike data with known underlying correlation dynamics. Finally, we apply the methods

  13. Immobilization of chloroperoxidase on mesoporous materials for the oxidation of 4,6-dimethyldibenzothiophene, a recalcitrant organic sulfur compound present in petroleum fractions.

    PubMed

    Terrés, Eduardo; Montiel, Mayra; Le Borgne, Sylvie; Torres, Eduardo

    2008-01-01

    The catalytic potential of chloroperoxidase (CPO) immobilized on mesoporous materials was evaluated for the oxidation of 4,6-dimethyldibenzothiophene in water/acetonitrile mixtures. Two different types of materials were used for the immobilization: a metal containing Al-MCM-41 material with a pore size of 26 A and SBA-16 materials with three different pore sizes: 40, 90 and 117 A. The SBA-16 40 A did not retain any CPO. The nature and the pore size of the material affected the catalytic activity of the enzyme as well as its stability. Compared to the free enzyme, the thermal stability of CPO at 45 degrees C was two and three times higher than when immobilized on Al-MCM-41 and SBA-16 90 A, respectively.

  14. Graphene-based electrochemical sensor for detection of 2,4,6-trinitrotoluene (TNT) in seawater: the comparison of single-, few-, and multilayer graphene nanoribbons and graphite microparticles.

    PubMed

    Goh, Madeline Shuhua; Pumera, Martin

    2011-01-01

    The detection of explosives in seawater is of great interest. We compared response single-, few-, and multilayer graphene nanoribbons and graphite microparticle-based electrodes toward the electrochemical reduction of 2,4,6-trinitrotoluene (TNT). We optimized parameters such as accumulation time, accumulation potential, and pH. We found that few-layer graphene exhibits about 20% enhanced signal for TNT after accumulation when compared to multilayer graphene nanoribbons. However, graphite microparticle-modified electrode provides higher sensitivity, and there was no significant difference in the performance of single-, few-, and multilayer graphene nanoribbons and graphite microparticles for the electrochemical detection of TNT. We established the limit of detection of TNT in untreated seawater at 1 μg/mL.

  15. Higher level phylogeny and the first divergence time estimation of Heteroptera (Insecta: Hemiptera) based on multiple genes.

    PubMed

    Li, Min; Tian, Ying; Zhao, Ying; Bu, Wenjun

    2012-01-01

    Heteroptera, or true bugs, are the largest, morphologically diverse and economically important group of insects with incomplete metamorphosis. However, the phylogenetic relationships within Heteroptera are still in dispute and most of the previous studies were based on morphological characters or with single gene (partial or whole 18S rDNA). Besides, so far, divergence time estimates for Heteroptera totally rely on the fossil record, while no studies have been performed on molecular divergence rates. Here, for the first time, we used maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference (BI) with multiple genes (18S rDNA, 28S rDNA, 16S rDNA and COI) to estimate phylogenetic relationships among the infraorders, and meanwhile, the Penalized Likelihood (r8s) and Bayesian (BEAST) molecular dating methods were employed to estimate divergence time of higher taxa of this suborder. Major results of the present study included: Nepomorpha was placed as the most basal clade in all six trees (MP trees, ML trees and Bayesian trees of nuclear gene data and four-gene combined data, respectively) with full support values. The sister-group relationship of Cimicomorpha and Pentatomomorpha was also strongly supported. Nepomorpha originated in early Triassic and the other six infraorders originated in a very short period of time in middle Triassic. Cimicomorpha and Pentatomomorpha underwent a radiation at family level in Cretaceous, paralleling the proliferation of the flowering plants. Our results indicated that the higher-group radiations within hemimetabolous Heteroptera were simultaneously with those of holometabolous Coleoptera and Diptera which took place in the Triassic. While the aquatic habitat was colonized by Nepomorpha already in the Triassic, the Gerromorpha independently adapted to the semi-aquatic habitat in the Early Jurassic.

  16. CDK4/6-dependent activation of DUB3 regulates cancer metastasis through SNAIL1.

    PubMed

    Liu, Tongzheng; Yu, Jia; Deng, Min; Yin, Yujiao; Zhang, Haoxing; Luo, Kuntian; Qin, Bo; Li, Yunhui; Wu, Chenming; Ren, Tao; Han, Yang; Yin, Peng; Kim, JungJin; Lee, SeungBaek; Lin, Jing; Zhang, Lizhi; Zhang, Jun; Nowsheen, Somaira; Wang, Liewei; Boughey, Judy; Goetz, Matthew P; Yuan, Jian; Lou, Zhenkun

    2017-01-09

    Tumour metastasis, the spread of cancer cells from the original tumour site followed by growth of secondary tumours at distant organs, is the primary cause of cancer-related deaths and remains poorly understood. Here we demonstrate that inhibition of CDK4/6 blocks breast tumour metastasis in the triple-negative breast cancer model, without affecting tumour growth. Mechanistically, we identify a deubiquitinase, DUB3, as a target of CDK4/6; CDK4/6-mediated activation of DUB3 is essential to deubiquitinate and stabilize SNAIL1, a key factor promoting epithelial-mesenchymal transition and breast cancer metastasis. Overall, our study establishes the CDK4/6-DUB3 axis as an important regulatory mechanism of breast cancer metastasis and provides a rationale for potential therapeutic interventions in the treatment of breast cancer metastasis.

  17. CDK4/6-dependent activation of DUB3 regulates cancer metastasis through SNAIL1

    PubMed Central

    Liu, Tongzheng; Yu, Jia; Deng, Min; Yin, Yujiao; Zhang, Haoxing; Luo, Kuntian; Qin, Bo; Li, Yunhui; Wu, Chenming; Ren, Tao; Han, Yang; Yin, Peng; Kim, JungJin; Lee, SeungBaek; Lin, Jing; Zhang, Lizhi; Zhang, Jun; Nowsheen, Somaira; Wang, Liewei; Boughey, Judy; Goetz, Matthew P.; Yuan, Jian; Lou, Zhenkun

    2017-01-01

    Tumour metastasis, the spread of cancer cells from the original tumour site followed by growth of secondary tumours at distant organs, is the primary cause of cancer-related deaths and remains poorly understood. Here we demonstrate that inhibition of CDK4/6 blocks breast tumour metastasis in the triple-negative breast cancer model, without affecting tumour growth. Mechanistically, we identify a deubiquitinase, DUB3, as a target of CDK4/6; CDK4/6-mediated activation of DUB3 is essential to deubiquitinate and stabilize SNAIL1, a key factor promoting epithelial–mesenchymal transition and breast cancer metastasis. Overall, our study establishes the CDK4/6–DUB3 axis as an important regulatory mechanism of breast cancer metastasis and provides a rationale for potential therapeutic interventions in the treatment of breast cancer metastasis. PMID:28067227

  18. COMPARISON OF BIOMARKERS IN WORKERS EXPOSED TO 2,4,6-TRINITROTOLUENE

    EPA Science Inventory

    2,4,6-Trinitrotoluene (TNT) is an important occupational and environmental pollutant. In TNT-exposed humans, the notable toxic manifestations have included aplastic anemia, toxic hepatitis, cataracts, hepatomegaly, and liver cancer. Therefore, we developed methods to biomonitor w...

  19. Seminar on the Associated Schools: N'Djamena, Chad, 4-6 May 1982.

    ERIC Educational Resources Information Center

    International Understanding at School, 1982

    1982-01-01

    Recommendations of a seminar held in N'Djamena, Chad, from May 4-6, 1982, to support the activities of the Associated Schools project intended to promote international understanding and peace are described. (RM)

  20. Role of higher excited electronic states on high harmonic generation in H2(+)--a time-independent Hermitian Floquet approach.

    PubMed

    Sarkar, Chitrakshya; Bhattacharyya, S S; Saha, Samir

    2011-01-14

    We have theoretically studied the role of high-lying molecular electronic states on the high harmonic generation (HHG) in H(2)(+) within the framework of a time-independent Hermitian nonperturbative three-dimensional Floquet technique for continuous wave monochromatic lasers of intensities of 2.59 × 10(13), 4.0 × 10(13), and 5.6 × 10(13) W∕cm(2), and wavelengths of 1064, 532, and 355 nm. To evaluate the HHG spectra, the resonance Floquet quasienergy and the Fourier components of the Floquet state corresponding to the initial vibrational-rotational level v = 0, J = 0 have been computed by solving the time-independent close-coupled Schrödinger equation following the Floquet method. The calculations include seven molecular electronic states in the basis set expansion of the Floquet state. The electronic states considered, apart from the two lowest 1sσ(g) and 2pσ(u) states, are 2pπ(u), 2sσ(g), 3pσ(u), 3dσ(g), and 4fσ(u). All the concerned higher excited molecular electronic states asymptotically degenerate into the atomic state H(2 l) with l = 0, 1. The computations reveal signature of significant oscillations in the HHG spectra due to the interference effect of the higher molecular electronic states for all the considered laser intensities and wavelengths. We have attempted to explain, without invoking any ionization, the dynamics of HHG in H(2)(+) within the framework of electronic transitions due to the electric dipole moments and the nuclear motions on the field coupled ground, the first and the higher excited electronic states of this one-electron molecular ion.

  1. Synthesis of Heteroaryl Sulfonamides from Organozinc Reagents and 2,4,6-Trichlorophenyl Chlorosulfate.

    PubMed

    Colombe, James R; DeBergh, J Robb; Buchwald, Stephen L

    2015-06-19

    A method for the preparation of aryl and heteroaryl sulfonamides using 2,4,6-trichlorophenyl chlorosulfate (TCPC) is described. The reaction of 2-pyridylzinc reagents with TCPC resulted in 2,4,6-trichlorophenyl (TCP) pyridine-2-sulfonates, and the parent pyridine-2-sulfonate was shown to react with amines. Less electron-rich aryl- and heteroarylzinc reagents reacted with TCPC to afford sulfonyl chlorides that were converted in situ to sulfonamides.

  2. Error Correcting 4/6 Modulation Codes for Holographic Data Storage

    NASA Astrophysics Data System (ADS)

    Kim, Jinyoung; Wee, Jae-Kyung; Lee, Jaejin

    2010-08-01

    We introduce error correcting 4/6 modulation codes for holographic data storage. Above all, the merit of the proposed modulation codes is that their trellis structure allows error correcting capability. The proposed codes also do not have any fatal (i.e., isolated pixels) two-dimensional intersymbol interference (2D ISI) patterns. The decoding scheme uses the Viterbi algorithm. As a result, the proposed codes have better performance than the conventional 6/8 and 4/6 modulation codes overall.

  3. Spiro[2.4]hepta-4,6-dienes: synthesis and application in organic synthesis

    NASA Astrophysics Data System (ADS)

    Menchikov, L. G.; Nefedov, O. M.

    2016-03-01

    This review integrates and describes systematically the data in the field of spiro[2.4]hepta-4,6-dienes published in the past 15 years. The changes in the development of studies that took place during this period are noted. The methods for the synthesis, the reactivity details and key chemical transformations of spiro[2.4]hepta-4,6-dienes are considered, with the emphasis on applications of these compounds in organic synthesis. The bibliography includes 207 references.

  4. Blind deconvolution of the seismic source time function based on higher order statistics of regional coda waves

    NASA Astrophysics Data System (ADS)

    Sèbe, Olivier; Guilbert, Jocelyn; Bard, Pierre-Yves

    2010-05-01

    Recovering the source time function (STF) of a seismic event provides essential information on the nature and physical mechanisms of the source. Nevertheless, the broad-band estimation of STF is often a difficult task particularly at regional distance where the unknown high heterogeneity of the crustal limits wave inversion to the low frequency content of the source. On the other hand, the widely used empirical Green's function (EGF) suffers from certain limitations towards the selection of valuable empirical green function, especially for small events. Several studies have proved the usefulness of the S coda wave for source parameter estimation such as its moment or its power spectrum. Unfortunately, as these methods are based on second order statistics (power spectrum), the phase of the source spectrum is lost as well as the event STF. In this study, we have developed an original method to recover STF based on the higher order statistic (HOS) blind deconvolution of the S wave coda excitation. Under the assumption that the coda excitation time series is a non-Gaussian independent and identically distributed random signal, this higher order spectral approach provides the amplitude and especially the phase of source spectrum, allowing thus the complete estimation of the seismic STF. We propose a two step algorithm to recover the seismic STF: first, the diffuse coda wave field is whitened to remove the non-stationary attenuation effect; second the STF of the event is estimated from the HOS of the whitened coda excitation such as its bicorrelation and tricorrelation. This algorithm has been tested on regional records of the Rambervillers, 22/02/2003, Ml=5.4 earthquake, located in North-east of France. As the convergence rate of the higher order statistic is slower than second order one, their estimation requires rather long time series and high signal to noise ratio. In order to improve the signal to noise ratio for HOS estimation, a multi-stations stacking procedure

  5. Final contamination assessment report, site 4-6, motor pool area. Version 3. 1. 19

    SciTech Connect

    Not Available

    1988-07-01

    This final report documents the phase I contamination survey of site 4-6, a vehicle maintenance area. A total of 36 borings, 1 soil grab sample, and 3 water samples yielded 169 samples. These samples were analyzed for volatile and semivolatile organics and metals. The following analytes were detected within or above their respective indicator ranges: C6H6, CHCl3, 11DClE, ETC6H6, CH2Cl2, TClEE, MEC6H5, 111TCE, TRClE, XYLEN, ALDRN, DBCP, CD, Cr, Cu, Pb, Zn, As, and Hg. Because the phase I survey has defined the general extent of potential contamination, no phase II program is planned at this time. However, ground water monitoring and the drilling of a limited number of borings near the fuel storage tanks are recommended. The volume of potentially contaminated material presented is estimated at 180,000 cubic yards. Appendices include chemical names, phase I chemical data, and comments and responses.

  6. Anaerobic transformation of 2,4,6-TNT by bovine ruminal microbes.

    PubMed

    Fleischmann, Thomas J; Walker, Karen C; Spain, Jim C; Hughes, Joseph B; Morrie Craig, A

    2004-02-20

    Degradation of TNT by bovine rumen fluid, a novel source of anaerobic microbes, was investigated. Whole rumen fluid contents were spiked with TNT and incubated for a 24h time period. Supernatant samples taken at 0, 1, 2, 4, and 24h were analyzed by reverse-phase HPLC with diode array detection. Within 1h, TNT was not detectable and reduction products of TNT including 2-hydroxyl-amino-4,6-dinitrotoluene, 4-hydroxylamino-2,6-dinitrotoluene, and 4-amino-2,6-dinitrotoluene were present with smaller amounts of diamino-nitrotoluenes. Within 2h, only the diamino and dihydroxyamino-nitrotoluene products remained. After 4h, 2,4-diamino-6-nitrotoluene and 2,4-dihydroxyamino-6-nitrotoluene were the only known molecular species left. At 24h known UV absorbing metabolites were no longer detected, suggesting further transformation such as complete reduction to triaminotoluene or destruction of the aromatic ring of TNT may have occurred. TNT was not transformed at 24h in autoclaved and buffered controls. This study presents the first direct evidence of biodegradation of TNT by ruminal microbes.

  7. Portable 4.6 Micrometers Laser Absorption Spectrometer for Carbon Monoxide Monitoring and Fire Detection

    NASA Technical Reports Server (NTRS)

    Briggs, Ryan M.; Frez, Clifford; Forouhar, Siamak; May, Randy D.; Ruff, Gary A.

    2013-01-01

    The air quality aboard manned spacecraft must be continuously monitored to ensure crew safety and identify equipment malfunctions. In particular, accurate real-time monitoring of carbon monoxide (CO) levels helps to prevent chronic exposure and can also provide early detection of combustion-related hazards. For long-duration missions, environmental monitoring grows in importance, but the mass and volume of monitoring instruments must be minimized. Furthermore, environmental analysis beyond low-Earth orbit must be performed in-situ, as sample return becomes impractical. Due to their small size, low power draw, and performance reliability, semiconductor-laser-based absorption spectrometers are viable candidates for this purpose. To reduce instrument form factor and complexity, the emission wavelength of the laser source should coincide with strong fundamental absorption lines of the target gases, which occur in the 3 to 5 micrometers wavelength range for most combustion products of interest, thereby reducing the absorption path length required for low-level concentration measurements. To address the needs of current and future NASA missions, we have developed a prototype absorption spectrometer using a semiconductor quantum cascade laser source operating near 4.6 micrometers that can be used to detect low concentrations of CO with a compact single-pass absorption cell. In this study, we present the design of the prototype instrument and report on measurements of CO emissions from the combustion of a variety of aerospace plastics.

  8. Chronic toxicity of 2,4,6-trinitrotoluene to a marine polychaete and an estuarine amphipod

    SciTech Connect

    Green, A.; Moore, D.; Farrar, D.

    1999-08-01

    The chronic toxicity of sediment-associated 2,4,6-trinitrotoluene (TNT) to the marine polychaete Neanthes arenaceodentata and the estuarine amphipod Leptocheirus plumulosus was evaluated. Test organisms were exposed to sediments spiked with radiolabeled TNT for 28 d, after which time the endpoints of mortality, growth, and reproduction (L. plumulosus only) were assayed and compared against the TNT tissue concentrations as well as the TNT sediment concentrations. Survival was significantly reduced at a tissue concentration of 61 {micro}g TNT/g wet wt tissue in N. arenaceodentata and L. plumulosus with enhancement (significant for N. arenaceodentata) occurring at the lower TNT concentrations. Growth was significantly reduced at the highest TNT exposure of 10.0 {micro}g TNT/g wet wt tissue in L. plumulosus. Reproduction was significantly reduced at a tissue concentration of 6.3 {micro}g TNT/g wet wt tissue in L. plumulosus. The results of this study demonstrate that both N. arenaceodentata and L. plumulosus are sensitive to the presence of sediment-associated TNT and that more information is needed about the toxicity of TNT to benthic fauna to facilitate risk assessment and management of TNT-contaminated sites.

  9. Collisional Destruction of FeC n - (n = 1 to 4, 6) Anions of Astrophysical Relevance

    NASA Astrophysics Data System (ADS)

    Nrisimhamurty, M.; Mane, R. G.; Chacko, Roby; Gupta, A. K.; Deshmukh, P. C.; Aravind, G.

    2016-12-01

    The stability of FeC- against dissociation in an astrophysical environment was probed by the collisional excitation of FeC-. Two anion resonances yielding Fe- and C- fragments were observed and studied through measurement of the kinetic energy released during fragmentation. The yield of Fe- was found to be nearly 5.5 times more than that of C- indicating the C- fragment to be in the loosely bound (2D) state. The possibility of avoided crossing leading to the observed fragment ion yield is also discussed. The dissociation of {{FeC}}n- (n = 2 to 4, 6) cluster anions predominantly resulted in the cleavage of Fe-C bond yielding only {{{C}}}n- fragments with similar energy release. The yield of {{{C}}}n- is discussed in the light of the observed abundances of HC n in IRC+10216. The importance of rotational transitions pertaining to both the ground and excited-electronic states of these cluster anions is discussed.

  10. Introducing conjoint analysis method into delayed lotteries studies: its validity and time stability are higher than in adjusting

    PubMed Central

    Białek, Michał; Markiewicz, Łukasz; Sawicki, Przemysław

    2015-01-01

    The delayed lotteries are much more common in everyday life than are pure lotteries. Usually, we need to wait to find out the outcome of the risky decision (e.g., investing in a stock market, engaging in a relationship). However, most research has studied the time discounting and probability discounting in isolation using the methodologies designed specifically to track changes in one parameter. Most commonly used method is adjusting, but its reported validity and time stability in research on discounting are suboptimal. The goal of this study was to introduce the novel method for analyzing delayed lotteries—conjoint analysis—which hypothetically is more suitable for analyzing individual preferences in this area. A set of two studies compared the conjoint analysis with adjusting. The results suggest that individual parameters of discounting strength estimated with conjoint have higher predictive value (Study 1 and 2), and they are more stable over time (Study 2) compared to adjusting. We discuss these findings, despite the exploratory character of reported studies, by suggesting that future research on delayed lotteries should be cross-validated using both methods. PMID:25674069

  11. Enhancement of microbial 2,4,6-trinitrotoluene transformation with increased toxicity by exogenous nutrient amendment.

    PubMed

    Liang, Shih-Hsiung; Hsu, Duen-Wei; Lin, Chia-Ying; Kao, Chih-Ming; Huang, Da-Ji; Chien, Chih-Ching; Chen, Ssu-Ching; Tsai, Isheng Jason; Chen, Chien-Cheng

    2017-04-01

    In this study, the bacterial strain Citrobacter youngae strain E4 was isolated from 2,4,6-trinitrotoluene (TNT)-contaminated soil and used to assess the capacity of TNT transformation with/without exogenous nutrient amendments. C. youngae E4 poorly degraded TNT without an exogenous amino nitrogen source, whereas the addition of an amino nitrogen source considerably increased the efficacy of TNT transformation in a dose-dependent manner. The enhanced TNT transformation of C. youngae E4 was mediated by increased cell growth and up-regulation of TNT nitroreductases, including NemA, NfsA and NfsB. This result indicates that the increase in TNT transformation by C. youngae E4 via nitrogen nutrient stimulation is a cometabolism process. Consistently, TNT transformation was effectively enhanced when C. youngae E4 was subjected to a TNT-contaminated soil slurry in the presence of an exogenous amino nitrogen amendment. Thus, effective enhancement of TNT transformation via the coordinated inoculation of the nutrient-responsive C. youngae E4 and an exogenous nitrogen amendment might be applicable for the remediation of TNT-contaminated soil. Although the TNT transformation was significantly enhanced by C. youngae E4 in concert with biostimulation, the 96-h LC50 value of the TNT transformation product mixture on the aquatic invertebrate Tigriopus japonicas was higher than the LC50 value of TNT alone. Our results suggest that exogenous nutrient amendment can enhance microbial TNT transformation; however, additional detoxification processes may be needed due to the increased toxicity after reduced TNT transformation.

  12. Computer-mediated communication and time pressure induce higher cardiovascular responses in the preparatory and execution phases of cooperative tasks.

    PubMed

    Costa Ferrer, Raquel; Serrano Rosa, Miguel Ángel; Zornoza Abad, Ana; Salvador Fernández-Montejo, Alicia

    2010-11-01

    The cardiovascular (CV) response to social challenge and stress is associated with the etiology of cardiovascular diseases. New ways of communication, time pressure and different types of information are common in our society. In this study, the cardiovascular response to two different tasks (open vs. closed information) was examined employing different communication channels (computer-mediated vs. face-to-face) and with different pace control (self vs. external). Our results indicate that there was a higher CV response in the computer-mediated condition, on the closed information task and in the externally paced condition. These role of these factors should be considered when studying the consequences of social stress and their underlying mechanisms.

  13. Pattern formations in miscellaneous mixtures of Bose-Einstein condensates and the higher-dimensional time-gated Manakov system

    SciTech Connect

    Kuetche, Victor K.; Bouetou, Thomas B.; Kofane, Timoleon C.; Moubissi, Alain B.; Porsezian, K.

    2010-11-15

    In this article, we investigate the structure and dynamics of miscellaneous mixtures of Bose-Einstein condensates confined within a time-independent anisotropic parabolic trap potential. In the zero-temperature mean-field approximation leading to coupled Gross-Pitaevskii equations for the macroscopic wave functions of the condensates, we show that these equations can be mapped onto the higher-dimensional time-gated Manakov system up to a first-order of accuracy. Paying particular attention to two-species mixtures and looking forward deriving a panel of miscellaneous excitations to the above equations, we analyze the singularity structure of the system by means of Weiss et al.'s [J. Weiss, M. Tabor, and G. Carnevale, J. Math. Phys. 24, 522 (1983); 25, 13 (1984).] methodology and provide its general Lax representation. As a result, we unearth a typical spectrum of localized and periodic coherent patterns while depicting elastic and nonelastic interactions among such structures alongside the splitting and resonance phenomena occurring during their motion.

  14. Energy-momentum conserving higher-order time integration of nonlinear dynamics of finite elastic fiber-reinforced continua

    NASA Astrophysics Data System (ADS)

    Erler, Norbert; Groß, Michael

    2015-05-01

    Since many years the relevance of fibre-reinforced polymers is steadily increasing in fields of engineering, especially in aircraft and automotive industry. Due to the high strength in fibre direction, but the possibility of lightweight construction, these composites replace more and more traditional materials as metals. Fibre-reinforced polymers are often manufactured from glass or carbon fibres as attachment parts or from steel or nylon cord as force transmission parts. Attachment parts are mostly subjected to small strains, but force transmission parts usually suffer large deformations in at least one direction. Here, a geometrically nonlinear formulation is necessary. Typical examples are helicopter rotor blades, where the fibres have the function to stabilize the structure in order to counteract large centrifugal forces. For long-run analyses of rotor blade deformations, we have to apply numerically stable time integrators for anisotropic materials. This paper presents higher-order accurate and numerically stable time stepping schemes for nonlinear elastic fibre-reinforced continua with anisotropic stress behaviour.

  15. Vicarious nucleophilic substitution to prepare 1,3-diamino-2,4,6-trinitrobenzene or 1,3,5-triamino-2,4,6-trinitrobenzene

    DOEpatents

    Mitchell, Alexander R.; Pagoria, Philip F.; Schmidt, Robert D.

    1996-01-01

    The present invention relates to a process to produce 1,3-diamino-2,4,6-trinitrobenzene (DATB) or 1,3,5-triamino-2,4,6,-trinitrobenzene (TATB) by: (a) reacting at ambient pressure and a temperature of between about 0.degree. and 50.degree. C. for between about 0.1 and 24 hr, a trinitroaromatic compound of structure V: ##STR1## wherein X, Y, and Z are each independently selected from --H, or --NH.sub.2, with the proviso that at least 1 or 2 of X, Y, and Z are hydrogen, with an amount effective to produce DATB or TATB of 1,1,1-trialkylhydrazinium halide wherein alkyl is selected from methyl, ethyl, propyl or butyl and halide is selected from chloride, bromide or iodide. in the presence of a strong base selected from sodium butoxide, potassium butoxide, potassium propoxide, sodium propoxide, sodium ethoxide, potassium ethoxide, sodium methoxide, potassium methoxide, and combinations thereof; in a solvent selected from the group consisting of methanol, ethanol, propanol, butanol, dimethylsulphoxide, N-methylpyrrolidone, hexamethylphosphoramide, dimethylformide, dimethylacetamide and mixtures thereof, provided that when alcohols are present primarily DATB and picramide is formed; and (b) isolating the DATB or TATB produced. DATB and TATB are useful specialty explosives. TATB is also used for the preparation of benzenehexamine, a starting material for the synthesis of novel materials (optical imaging devices, liquid crystals, ferromagnetic compounds).

  16. Vicarious nucleophilic substitution to prepare 1,3-diamino-2,4,6-trinitrobenzene or 1,3,5-triamino-2,4,6-trinitrobenzene

    DOEpatents

    Mitchell, A.R.; Pagoria, P.F.; Schmidt, R.D.

    1996-10-29

    The present invention relates to a process to produce 1,3-diamino-2,4,6-trinitrobenzene (DATB) or 1,3,5-triamino-2,4,6,trinitrobenzene (TATB) by: (a) reacting at ambient pressure and a temperature of between about 0 and 50 C for between about 0.1 and 24 hr, a trinitroaromatic compound of the structure shown within where X, Y, and Z are each independently selected from --H, or --NH{sub 2}, with the proviso that at least 1 or 2 of X, Y, and Z are hydrogen, with an amount effective to produce DATB or TATB, or 1,1,1-trialkylhydrazinium halide wherein alkyl is selected from methyl, ethyl, propyl or butyl and halide is selected from chloride, bromide or iodide, in the presence of a strong base selected from sodium butoxide, potassium butoxide, potassium propoxide, sodium propoxide, sodium ethoxide, potassium ethoxide, sodium methoxide, potassium methoxide, and combinations thereof; in a solvent selected from the group consisting of methanol, ethanol, propanol, butanol, dimethylsulfoxide, N-methylpyrrolidone, hexamethylphosphoramide, dimethylformide, dimethylacetamide and mixtures thereof, provided that when alcohols are present primarily DATB and picramide is formed; and (b) isolating the DATB or TATB produced. DATB and TATB are useful specialty explosives. TATB is also used for the preparation of benzenehexamine, a starting material for the synthesis of novel materials (optical imaging devices, liquid crystals, ferromagnetic compounds).

  17. Anaerobic degradation of 2,4,6-trinitrotoluene in granular activated carbon fluidized bed and batch reactors.

    PubMed

    Moteleb, M A; Suidan, M T; Kim, J; Davel, J L; Adrian, N R

    2001-01-01

    In this study, an anaerobic fluidized bed reactor (AFBR) was used to treat a synthetically produced pink water waste stream containing trinitrotoluene (TNT). The synthesized waste consisted of 95 mg/l-TNT, the main contaminant in pink water, which was to be co-metabolized with 560-mg/l ethanol. Granular activated carbon was used as the attachment medium for biological growth. TNT was reduced to a variety of compounds, mainly 2,4,6-triaminotoluene (2,4,6-TAT), 2,4-diamino-6-nitrotoluene (2,4-DA-6-NT), 2,6-diamino-4-nitrotoluene (2,6-DA-4-NT), 2-amino-4,6-dinitrotoluene (2-A-4,6-DNT), and 4-amino-2,6-dinitrotoluene (4-A-2,6-DNT). These conversions resulted through the oxidation of ethanol to carbon dioxide under anoxic conditions, or reduction to methane under methanogenic conditions. The anaerobic reactor was charged with 1.0 kg of 16 x 20 U.S. Mesh Granular Activated Carbon (GAC) and was pre-loaded with 200 g of TNT prior to the addition of the mixed seed culture. During the first three weeks of operation, ethanol was completely degraded and no methane was produced. Effluent inorganic carbon revealed stoichiometric conversion of the feed ethanol to dissolved inorganic carbon with accumulation of carbon dioxide in the headspace of the reactor. GAC extraction showed incremental reduction of the nitro groups to amino groups, with 2,4,6-TAT as the final product. After three weeks, the oxygen from the nitro groups was depleted and methane production commenced. The reproducibility of this phenomenon was confirmed by repeating the experiment in the same manner using an identical AFBR. Furthermore, serum bottle tests were conducted using TNT loading ratios of 0.2, 0.4, 0.8, 1.0 g-TNT/g-GAC as well as experiments in the absence of GAC. Similar behavior to that of the columns was observed, with degradation rates varying according to the particular condition. GAC greatly enhanced the degradation rates and the higher TNT loading resulted in slower degradation rates of ethanol.

  18. Real-time evaluation of individual cow milk for higher cheese-milk quality with increased cheese yield.

    PubMed

    Katz, G; Merin, U; Bezman, D; Lavie, S; Lemberskiy-Kuzin, L; Leitner, G

    2016-06-01

    Cheese was produced in a series of experiments from milk separated in real time during milking by using the Afilab MCS milk classification service (Afikim, Israel), which is installed on the milk line in every stall and sorts milk in real time into 2 target tanks: the A tank for cheese production (CM) and the B tank for fluid milk products (FM). The cheese milk was prepared in varying ratios ranging from ~10:90 to ~90:10 CM:FM by using this system. Cheese was made with corrected protein-to-fat ratio and without it, as well as from milk stored at 4°C for 1, 2, 3, 4, and 8d before production. Cheese weight at 24h increased along the separation cutoff level with no difference in moisture, and dry matter increased. The data compiled allowed a theoretical calculation of cheese yield and comparing it to the original van Slyke equation. Whenever the value of Afi-Cf, which is the optical measure of curd firmness obtained by the Afilab instrument, was used, a better predicted level of cheese yield was obtained. In addition, 27 bulk milk tanks with milk separated at a 50:50 CM:FM ratio resulted in cheese with a significantly higher fat and protein, dry matter, and weight at 24h. Moreover, solids incorporated from the milk into the cheese were significantly higher in cheeses made of milk from A tanks. The influence of storage of milk up to 8d before cheese making was tested. Gross milk composition did not change and no differences were found in cheese moisture, but dry matter and protein incorporated in the cheese dropped significantly along the storage time. These findings confirm that milk stored for several days before processing is prone to physico-chemical deterioration processes, which result in loss of milk constituents to the whey and therefore reduced product yield. The study demonstrates that introducing the unknown parameters for calculating the predicted cheese yield, such as the empiric measured Afi-Cf properties, are more accurate and the increase in cheese

  19. A novel Fast Gas Chromatography based technique for higher time resolution measurements of speciated monoterpenes in air

    NASA Astrophysics Data System (ADS)

    Jones, C. E.; Kato, S.; Nakashima, Y.; Kajii, Y.

    2013-12-01

    Biogenic emissions supply the largest fraction of non-methane volatile organic compounds (VOC) from the biosphere to the atmospheric boundary layer, and typically comprise a complex mixture of reactive terpenes. Due to this chemical complexity, achieving comprehensive measurements of biogenic VOC (BVOC) in air within a satisfactory time resolution is analytically challenging. To address this, we have developed a novel, fully automated Fast Gas Chromatography (Fast-GC) based technique to provide higher time resolution monitoring of monoterpenes (and selected other C9-C15 terpenes) during plant emission studies and in ambient air. To our knowledge, this is the first study to apply a Fast-GC based separation technique to achieve quantification of terpenes in air. Three chromatography methods have been developed for atmospheric terpene analysis under different sampling scenarios. Each method facilitates chromatographic separation of selected BVOC within a significantly reduced analysis time compared to conventional GC methods, whilst maintaining the ability to quantify individual monoterpene structural isomers. Using this approach, the C10-C15 BVOC composition of single plant emissions may be characterised within a ~ 14 min analysis time. Moreover, in situ quantification of 12 monoterpenes in unpolluted ambient air may be achieved within an ~ 11 min chromatographic separation time (increasing to ~ 19 min when simultaneous quantification of multiple oxygenated C9-C10 terpenoids is required, and/or when concentrations of anthropogenic VOC are significant). This corresponds to a two- to fivefold increase in measurement frequency compared to conventional GC methods. Here we outline the technical details and analytical capability of this chromatographic approach, and present the first in situ Fast-GC observations of 6 monoterpenes and the oxygenated BVOC linalool in ambient air. During this field deployment within a suburban forest ~ 30 km west of central Tokyo, Japan, the

  20. Preclinical Therapeutic Synergy of MEK1/2 and CDK4/6 Inhibition in Neuroblastoma.

    PubMed

    Hart, Lori S; Rader, JulieAnn; Raman, Pichai; Batra, Vandana; Russell, Mike R; Tsang, Matthew; Gagliardi, Maria; Chen, Lucy; Martinez, Daniel; Li, Yimei; Wood, Andrew; Kim, Sunkyu; Parasuraman, Sudha; Delach, Scott; Cole, Kristina A; Krupa, Shiva; Boehm, Markus; Peters, Malte; Caponigro, Giordano; Maris, John M

    2017-04-01

    Purpose: Neuroblastoma is treated with aggressive multimodal therapy, yet more than 50% of patients experience relapse. We recently showed that relapsed neuroblastomas frequently harbor mutations leading to hyperactivated ERK signaling and sensitivity to MEK inhibition therapy. Here we sought to define a synergistic therapeutic partner to potentiate MEK inhibition.Experimental Design: We first surveyed 22 genetically annotated human neuroblastoma-derived cell lines (from 20 unique patients) for sensitivity to the MEK inhibitor binimetinib. After noting an inverse correlation with sensitivity to ribociclib (CDK4/6 inhibitor), we studied the combinatorial effect of these two agents using proliferation assays, cell-cycle analysis, Ki67 immunostaining, time-lapse microscopy, and xenograft studies.Results: Sensitivity to binimetinib and ribociclib was inversely related (r = -0.58, P = 0.009). MYCN amplification status and expression were associated with ribociclib sensitivity and binimetinib resistance, whereas increased MAPK signaling was the main determinant of binimetinib sensitivity and ribociclib resistance. Treatment with both compounds resulted in synergistic or additive cellular growth inhibition in all lines tested and significant inhibition of tumor growth in three of four xenograft models of neuroblastoma. The augmented growth inhibition was attributed to diminished cell-cycle progression that was reversible upon removal of drugs.Conclusions: Here we demonstrate that combined binimetinib and ribociclib treatment shows therapeutic synergy across a broad panel of high-risk neuroblastoma preclinical models. These data support testing this combination therapy in relapsed high-risk neuroblastoma patients, with focus on cases with hyperactivated RAS-MAPK signaling. Clin Cancer Res; 23(7); 1785-96. ©2016 AACR.

  1. Characterization of the IEC 61000-4-6 Electromagnetic Clamp for Conducted-Immunity Testing

    NASA Astrophysics Data System (ADS)

    Grassi, F.; Pignari, S. A.; Spadacini, G.; Toscani, N.; Pelissou, P.

    2016-05-01

    A multiconductor transmission line model (MTL) is used to investigate the operation of the IEC 61000-4-6 electromagnetic (EM) clamp in a conducted-immunity test setup for aerospace applications. Aspects of interest include the performance of such a coupling device at very high frequencies (up to 1 GHz), and for extreme values of the common-mode impedance of equipment (short circuits, open circuits). The MTL model is finally exploited to predict the frequency response of coupling and decoupling factors defined in the IEC 61000-4-6 standard.

  2. 2,3,4,6-Tetrachlorophenyl esters as antiseptics for fibrous materials

    SciTech Connect

    Stepanenko, N.I.; Ryakhovskaya, A.I.; Romanenko, O.A.; Garifullina, K.R.

    1983-09-10

    Wastes containing tri- and tetrachlorobenzenes are obtained during production of di- and trichlorobenzenes. One way of utilizing these wastes is conversion into di- and trichlorophenols by saponification. Chlorination of a mixture of di- and trichlorophenols converts it into 2,3,4,6-tetrachlorophenol with high yields (95-96 wt. %). The uses of tetrachlorophenol are limited by its strong specific odor and volatility. The possibility of obtaining esters of 2,3,4,6-tetrachlorophenol and saturated aliphatic C/sub 2/-C/sub 12/ monocarboxylic acids, which have good antiseptic properties in relation to fibrous materials are described.

  3. Assessments of higher-order ionospheric effects on GPS coordinate time series: A case study of CMONOC with longer time series

    NASA Astrophysics Data System (ADS)

    Jiang, Weiping; Deng, Liansheng; Zhou, Xiaohui; Ma, Yifang

    2014-05-01

    Higher-order ionospheric (HIO) corrections are proposed to become a standard part for precise GPS data analysis. For this study, we deeply investigate the impacts of the HIO corrections on the coordinate time series by implementing re-processing of the GPS data from Crustal Movement Observation Network of China (CMONOC). Nearly 13 year data are used in our three processing runs: (a) run NO, without HOI corrections, (b) run IG, both second- and third-order corrections are modeled using the International Geomagnetic Reference Field 11 (IGRF11) to model the magnetic field, (c) run ID, the same with IG but dipole magnetic model are applied. Both spectral analysis and noise analysis are adopted to investigate these effects. Results show that for CMONOC stations, HIO corrections are found to have brought an overall improvement. After the corrections are applied, the noise amplitudes decrease, with the white noise amplitudes showing a more remarkable variation. Low-latitude sites are more affected. For different coordinate components, the impacts vary. The results of an analysis of stacked periodograms show that there is a good match between the seasonal amplitudes and the HOI corrections, and the observed variations in the coordinate time series are related to HOI effects. HOI delays partially explain the seasonal amplitudes in the coordinate time series, especially for the U component. The annual amplitudes for all components are decreased for over one-half of the selected CMONOC sites. Additionally, the semi-annual amplitudes for the sites are much more strongly affected by the corrections. However, when diplole model is used, the results are not as optimistic as IGRF model. Analysis of dipole model indicate that HIO delay lead to the increase of noise amplitudes, and that HIO delays with dipole model can generate false periodic signals. When dipole model are used in modeling HIO terms, larger residual and noise are brought in rather than the effective improvements.

  4. Study of Interpolated Timing Recovery Phase-Locked Loop with Linearly Constrained Adaptive Prefilter for Higher-Density Optical Disc

    NASA Astrophysics Data System (ADS)

    Kajiwara, Yoshiyuki; Shiraishi, Junya; Kobayashi, Shoei; Yamagami, Tamotsu

    2009-03-01

    A digital phase-locked loop (PLL) with a linearly constrained adaptive filter (LCAF) has been studied for higher-linear-density optical discs. LCAF has been implemented before an interpolated timing recovery (ITR) PLL unit in order to improve the quality of phase error calculation by using an adaptively equalized partial response (PR) signal. Coefficient update of an asynchronous sampled adaptive FIR filter with a least-mean-square (LMS) algorithm has been constrained by a projection matrix in order to suppress the phase shift of the tap coefficients of the adaptive filter. We have developed projection matrices that are suitable for Blu-ray disc (BD) drive systems by numerical simulation. Results have shown the properties of the projection matrices. Then, we have designed the read channel system of the ITR PLL with an LCAF model on the FPGA board for experiments. Results have shown that the LCAF improves the tilt margins of 30 gigabytes (GB) recordable BD (BD-R) and 33 GB BD read-only memory (BD-ROM) with a sufficient LMS adaptation stability.

  5. SAGE ANALYSIS OF TRANSCRIPTOME RESPONSES IN ARABIDOPSIS ROOTS EXPOSED TO 2,4,6-TRINITROTOLUENE

    EPA Science Inventory

    Serial Analysis of Gene Expression (SAGE) was used to profile transcript levels in Arabidopsis thaliana roots and assess their responses to 2,4,6-trinitrotoluene (TNT) exposure. SAGE libraries representing control and TNT-exposed seedling root transcripts were constructed, and ea...

  6. Study of Vermont: A Curriculum Designed for Grades 4-6.

    ERIC Educational Resources Information Center

    Dubuque, Martha L.

    Designed for use in grades 4-6, this guide consists of four basic units related to the study of Vermont: Indian Civilization, Vermont History, Geography and Economics, and Cities and Towns. Each unit lists key concepts, content objectives, skills objectives, and related objectives. Next, specialized vocabulary as well as common, essential…

  7. Travel On! Mini-Units and Learning Activities on Transportation for Grades 4-6.

    ERIC Educational Resources Information Center

    Lawson, Jane; And Others

    One of a series of eleven curriculum manuals which cover the four transportation topics of public transportation, transportation and the environment, transportation safety, and bicycles for elementary, secondary, and adult levels, this manual for grades 4-6 covers all four topics. Materials in four chapters comprising fourteen mini-units cover…

  8. The Uncomplicated Elementary Career Education System for the "Real" Classroom. Career Capers for 4-6.

    ERIC Educational Resources Information Center

    Illinois State Office of Education, Springfield. Div. of Adult Vocational and Technical Education.

    Prepared by classroom teachers for the infusion of career education into existing curriculum, this notebook of student and teacher activities is designed for use with the monthly Factivities for grades 4-6 (CE 023 596). Each activity corresponds to one of the nine monthly topics: "me, myself, and I"; exploring the telephone book; transportation;…

  9. SOIL REDUCES 2,4,6-TRINITROTOLUENE BIOAVAILABILITY AND GENOTOXICITY IN VIVO

    EPA Science Inventory

    Soil Reduces 2,4,6- Trinitrotoluene Bioavailability and Genotoxicity In Vivo

    As chemicals age in soil, irreversible binding of chemical contaminants to organic components in the soil may occur, impacting the amount of chemical that is biologically available upon exp...

  10. The Navajo Way of Life: A Resource Unit with Activities for Grades 4-6.

    ERIC Educational Resources Information Center

    Cordova, Dahlia

    A resource unit on the Navajo way of life, for grades 4-6, contains sections on Navajo history, art, and crafts, homes, music, poetry and games; Navajo and Pueblo cookery (including recipes); traditional Navajo dress, ceremony and legends; and successful Navajos, past and present. Sections include text, vocabulary words, drawings, maps, and…

  11. Preparation of 1,3,5-triamo-2,4,6-trinitrobenzene of submicron particle size

    DOEpatents

    Rigdon, Lester P.; Moody, Gordon L.; McGuire, Raymond R.

    2001-05-01

    A method is disclosed for the preparation of very small particle size, relatively pure 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). Particles of TATB prepared according to the disclosed method are of submicron size and have a surface area in the range from about 3.8 to 27 square meters per gram.

  12. Polarization observables in the elastic scattering of protons from {sup 4,6,8}He

    SciTech Connect

    Crespo, R.; Moro, A. M.

    2007-11-15

    We have calculated the p-{sup 4,6,8}He elastic scattering differential cross section and polarizations at 297 MeV using the Multiple Scattering expansion of the Optical potential (MSO) reaction scattering framework. The role of the core and valence neutrons contribution to the interaction in the description of the elastic scattering observables is analyzed.

  13. The Greatest Educational Change America Has Ever Seen, 2002: Lesson Plans for Grades 4-6.

    ERIC Educational Resources Information Center

    United States Mint (Dept. of Treasury), Washington, DC.

    This teacher's guide on the 50 state quarters emitted by the United States Mint includes 6 "teacher-friendly" lesson plans that fit easily into the curriculum for grades 4-6; reproducible student worksheets that coincide with each lesson; "fun" state facts and information on the new quarter designs; and USA map template with…

  14. The Greatest Educational Change America Has Ever Seen, 2001: Lesson Plans for Grades 4-6.

    ERIC Educational Resources Information Center

    United States Mint (Dept. of Treasury), Washington, DC.

    This teacher's guide on the 50 state quarters produced by the United States Mint includes six lesson plans that fit easily into the social studies curriculum for grades 4-6. The lesson plans include reproducible student work pages that coincide with each lesson; state facts and information about the 2001 state quarter designs (New York, North…

  15. The Greatest Educational Change America Has Ever Seen. [Teaching Guide]. Grades 4-6.

    ERIC Educational Resources Information Center

    United States Mint (Dept. of Treasury), Washington, DC.

    This teaching guide for grades 4-6 focuses on the 1999-2000 United States Mint 50 State Quarters Program, which includes new quarter designs for the following states: Delaware, Pennsylvania, New Jersey, Georgia, Connecticut, Massachusetts, Maryland, South Carolina, New Hampshire, and Virginia. The guide includes six lesson plans that fit easily…

  16. TOXICITY OF TETRYL (N-METHYL-N,2,4,6-TETRANITROANILINE) IN F344 RATS

    EPA Science Inventory

    The toxicity of tetryl (N-methyl-N,2,4,6-tetranitroaniline) in male and female F344 rats was evaluated after adminstration in the diet for 14 or 90 days. The 14-day study diet concentrations used were 0, 500, 1250, 2000, 2500, and 5000 ppm; the 90-day study diet concentrations we...

  17. 43 CFR 1610.4-6 - Estimation of effects of alternatives.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR GENERAL MANAGEMENT (1000) PLANNING, PROGRAMMING, BUDGETING Resource Management Planning § 1610.4-6 Estimation of effects of alternatives. The Field Manager... effects shall be guided by the planning criteria and procedures implementing the National...

  18. 43 CFR 3862.4-6 - Payment of purchase price and statement of charges and fees.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MINERAL PATENT APPLICATIONS Lode Mining Claim Patent Applications § 3862.4-6 Payment of purchase price and statement of... publication and surveys, together with all fees and money paid the authorized officer of the proper...

  19. 43 CFR 3862.4-6 - Payment of purchase price and statement of charges and fees.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MINERAL PATENT APPLICATIONS Lode Mining Claim Patent Applications § 3862.4-6 Payment of purchase price and statement of... publication and surveys, together with all fees and money paid the authorized officer of the proper...

  20. 43 CFR 3862.4-6 - Payment of purchase price and statement of charges and fees.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MINERAL PATENT APPLICATIONS Lode Mining Claim Patent Applications § 3862.4-6 Payment of purchase price and statement of... publication and surveys, together with all fees and money paid the authorized officer of the proper...

  1. 43 CFR 3862.4-6 - Payment of purchase price and statement of charges and fees.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MINERAL PATENT APPLICATIONS Lode Mining Claim Patent Applications § 3862.4-6 Payment of purchase price and statement of... publication and surveys, together with all fees and money paid the authorized officer of the proper...

  2. Mineralization of 2,4,6-Trinitrotoleune (TNT) in Coastal Waters and Sediments

    DTIC Science & Technology

    2006-08-21

    sp. and Staphylococcus sp. (Kalafut et al. 1998), actinomycetes (Pasti- Grigsby et al. 1996), Enterobacter cloacae (French et al. 1998), Klebsiella sp...Pasti-Grigsby, MB, Lewis, TA, Crawford, DL, Crawford, RL (1996). Transformation of 2,4,6- Trinitrotoluene (TNT) by Actinomycetes isolated from TNT

  3. Teaching Writing in Grades 4-6 in Urban Schools in the Greater China Region

    ERIC Educational Resources Information Center

    Hsiang, Tien Ping; Graham, Steve

    2016-01-01

    A random sample of 1102 grade 4-6 Chinese language arts teachers in Beijing, Macao, and Taipei City were surveyed about their instructional writing practices. Seventy-eight percent (n = 857) of the teachers completed the survey. Teachers were generally positive about the usefulness of their college teacher preparation program. They slightly agreed…

  4. Teaching New Literacies in Grades 4-6: Resources for 21st-Century Classrooms

    ERIC Educational Resources Information Center

    Moss, Barbara, Ed.; Lapp, Diane, Ed.

    2009-01-01

    Upper-elementary students encounter a sometimes dizzying array of traditional and nontraditional texts both in and outside of the classroom. This practical handbook helps teachers in grades 4-6 harness the instructional potential of fiction, poetry, and plays; informational texts; graphic novels; digital storytelling; Web-based and multimodal…

  5. Living in Water. An Aquatic Science Curriculum for Grades 4-6. Second Edition.

    ERIC Educational Resources Information Center

    National Aquarium in Baltimore, MD. Dept. of Education.

    This document is a scientific study of water, aquatic environments and the plants and animals that live in water. It was written for grades 4-6 but many activities may also be of interest for use with older students. This curriculum covers both marine and freshwater habitats. Each of five sections addresses a question about water which is then…

  6. Federal Aviation Administration Aviation Education Teacher's Guide, [Grades] 4-6.

    ERIC Educational Resources Information Center

    Federal Aviation Administration (DOT), Washington, DC.

    This guide is one in a series of four resource guides specifically designed for those interested in aviation education. Activities and lessons that can be used in a variety of content areas and grade levels are featured. Grades 4-6 are the focus of this guide, which is organized under the broad topics of properties of air, lighter than air flight,…

  7. PCE/K-10 Activities for Career Education, Grades 4-6.

    ERIC Educational Resources Information Center

    Portland Public Schools, OR. Area II Office.

    The Portland (Oregon) Public School Project Career Education (PCE) Activities for grades 4-6 is based on the city's overall Area 2 program goals for career education which proposed that children completing school should have sufficient knowledge and competencies to enter into a field of employment or an advanced training program in that field.…

  8. Explorations in Backyard Biology: Drawing on Nature in the Classroom, Grades 4-6.

    ERIC Educational Resources Information Center

    Raham, R. Gary

    This book is designed to guide students grades 4-6 in exploring new worlds of adventure in the life sciences. Students read short features on creatures as near as their own backyards, are invited to expand their interest with classroom and field activities, and are shown how to use drawing and writing skills to record their experiences in a…

  9. The Synthesis of 4,6,8-Trimethylazulene: An Organic Laboratory Experiment.

    ERIC Educational Resources Information Center

    Garst, Michael E.; And Others

    1983-01-01

    A two-stage synthesis of 4,6,8-trimethylazulene was developed for use in the undergraduate experiment, highlighting concepts not usually covered in the laboratory. The experiment requires purification procedures of chromatography and of sublimation and illustrates concepts of aromaticity, molecular orbital theory, and carbodium ion reactivity. (JN)

  10. BIOTRANSFORMATION OF 2,4,6-TRINITROTOLUENE (TNT) BY A PLANT-ASSOCIATED FUNGUS FUSARIUM OXYSPORUM

    EPA Science Inventory

    The capability of a plant-associated fungus, Fusarium oxyvorum, to transform TNT in liquid cultures was investigated. TNT was transformed into 2-amino-4, 6-dinitrotoluene (2-A-DNT), 4-amino-2, 6-dinitrotoluene (4-A- DNT), and 2, 4-diamino-6-nitrotoluene (2, 4-DAT) via 2- and 4-hy...

  11. Texas School Survey of Substance Use among Students: Grades 4-6, 1998.

    ERIC Educational Resources Information Center

    Wallisch, Lynn S.; Liu, Liang Y.

    This booklet reports on the results of the 1998 Texas School Survey of Substance Use among Students: Grades 4-6. The statewide school survey monitors trends in substance use among public school students, identifies emerging problem areas, and serves as a basis of comparison for local school surveys which are conducted annually by various school…

  12. Planet Patrol. An Environmental Unit on Solid Waste Solutions for Grades 4-6.

    ERIC Educational Resources Information Center

    Procter and Gamble Educational Services, Cincinnati, OH.

    This classroom unit was developed for use in grades 4-6 to help teach the concept of solid waste management. The teacher's guide provides an overview of the issue of solid waste disposal, a description of government, industry, and consumer roles in resolving the solid waste issue, and four lessons involving sanitary landfills, the reduction of…

  13. 42 CFR 4.6 - Reference, bibliographic, reproduction, and consultation services.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Reference, bibliographic, reproduction, and... SERVICES GENERAL PROVISIONS NATIONAL LIBRARY OF MEDICINE § 4.6 Reference, bibliographic, reproduction, and... request, reference, bibliographic, reproduction, and consultation services. Priority will be given...

  14. 42 CFR 4.6 - Reference, bibliographic, reproduction, and consultation services.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Reference, bibliographic, reproduction, and... SERVICES GENERAL PROVISIONS NATIONAL LIBRARY OF MEDICINE § 4.6 Reference, bibliographic, reproduction, and... request, reference, bibliographic, reproduction, and consultation services. Priority will be given...

  15. 42 CFR 4.6 - Reference, bibliographic, reproduction, and consultation services.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Reference, bibliographic, reproduction, and... SERVICES GENERAL PROVISIONS NATIONAL LIBRARY OF MEDICINE § 4.6 Reference, bibliographic, reproduction, and... request, reference, bibliographic, reproduction, and consultation services. Priority will be given...

  16. 42 CFR 4.6 - Reference, bibliographic, reproduction, and consultation services.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Reference, bibliographic, reproduction, and... SERVICES GENERAL PROVISIONS NATIONAL LIBRARY OF MEDICINE § 4.6 Reference, bibliographic, reproduction, and... request, reference, bibliographic, reproduction, and consultation services. Priority will be given...

  17. 42 CFR 4.6 - Reference, bibliographic, reproduction, and consultation services.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Reference, bibliographic, reproduction, and... SERVICES GENERAL PROVISIONS NATIONAL LIBRARY OF MEDICINE § 4.6 Reference, bibliographic, reproduction, and... request, reference, bibliographic, reproduction, and consultation services. Priority will be given...

  18. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene of submicron particle size

    DOEpatents

    Rigdon, Lester P.; Moody, Gordon L.; McGuire, Raymond R.

    2001-01-01

    A method is disclosed for the preparation of very small particle size, relatively pure 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). Particles of TATB prepared according to the disclosed method are of submicron size and have a surface area in the range from about 3.8 to 27 square meters per gram.

  19. A Curriculum in Written Composition, 4-6: A Guide for Teaching.

    ERIC Educational Resources Information Center

    Georgia Univ., Athens. English Curriculum Study Center.

    This guide for teaching composition in grades 4-6 (1) objectives for a curriculum in written composition, (2) sequence charts which relate subject content for each grade to basic understandings about composition, (3) illustrative learning experiences, and (4) units for teaching specific skills. The units for each grade are "Structuring a…

  20. 43 CFR 2650.4-6 - National wildlife refuge system lands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false National wildlife refuge system lands... SELECTIONS Alaska Native Selections: Generally § 2650.4-6 National wildlife refuge system lands. (a) Every conveyance which includes lands within the national wildlife refuge system shall, as to such lands,...

  1. 43 CFR 2650.4-6 - National wildlife refuge system lands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false National wildlife refuge system lands... SELECTIONS Alaska Native Selections: Generally § 2650.4-6 National wildlife refuge system lands. (a) Every conveyance which includes lands within the national wildlife refuge system shall, as to such lands,...

  2. 43 CFR 2650.4-6 - National wildlife refuge system lands.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false National wildlife refuge system lands... SELECTIONS Alaska Native Selections: Generally § 2650.4-6 National wildlife refuge system lands. (a) Every conveyance which includes lands within the national wildlife refuge system shall, as to such lands,...

  3. 43 CFR 2650.4-6 - National wildlife refuge system lands.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false National wildlife refuge system lands... SELECTIONS Alaska Native Selections: Generally § 2650.4-6 National wildlife refuge system lands. (a) Every conveyance which includes lands within the national wildlife refuge system shall, as to such lands,...

  4. Toxics in My Home? You Bet! Curriculum on Household Toxics for Grades 4-6.

    ERIC Educational Resources Information Center

    Purin, Gina; And Others

    This curriculum consists of a one-week course of study designed to introduce students in grades 4-6 to (or increase their awareness of) toxic substances commonly found in the home. It includes an introduction/conceptual framework, four lessons, a unit evaluation, and appendices. Each lesson consists of a statement of purpose, objectives,…

  5. Convenient large-scale synthesis of D-glucaro-1,4:6,3-dilactone.

    PubMed

    Gehret, Troy C; Frobese, A Stephen; Zerbe, James S; Chenault, H Keith

    2009-11-06

    Calcium D-glucarate was converted into D-glucaro-1,4:6,3-dilactone on 32-g, 1-kg, and 22-kg scale, using azeotropic distillation with methyl isobutyl ketone to drive the dehydration. The crystalline product was > or = 99.5% pure by GC and NMR, and overall yield was as high as 72%.

  6. Higher Urinary Lignan Concentrations in Women but Not Men Are Positively Associated with Shorter Time to Pregnancy1234

    PubMed Central

    Mumford, Sunni L.; Sundaram, Rajeshwari; Schisterman, Enrique F.; Sweeney, Anne M.; Barr, Dana Boyd; Rybak, Michael E.; Maisog, Jose M.; Parker, Daniel L.; Pfeiffer, Christine M.; Louis, Germaine M. Buck

    2014-01-01

    Phytoestrogens have been associated with subtle hormonal changes, although effects on fecundity are unknown. Our objective was to evaluate the association between male and female urinary phytoestrogen (isoflavone and lignan) concentrations and time to pregnancy (TTP) in a population-based cohort of 501 couples desiring pregnancy and discontinuing contraception. Couples were followed for 12 mo or until pregnancy. Fecundability ORs (FORs) and 95% CIs were estimated after adjusting for age, body mass index, race, site, creatinine, supplement use, and physical activity in relation to female, male, and joint couple concentrations. Models included the phytoestrogen of interest and the sum of the remaining individual phytoestrogens. FORs <1 denote a longer TTP and FORs >1 a shorter TTP. Urinary lignan concentrations were higher, on average, among female partners of couples who became pregnant during the study compared with women who did not become pregnant (median enterodiol: 118 vs. 80 nmol/L; P < 0.10; median enterolactone: 990 vs. 412 nmol/L; P < 0.05) and were associated with significantly shorter TTP in models based on both individual and couples’ concentrations (couples' models: enterodiol FOR, 1.13; 95% CI: 1.02, 1.26; enterolactone FOR, 1.11; 95% CI: 1.01, 1.21). Male lignan concentrations were not associated with TTP, nor were isoflavone concentrations. Sensitivity analyses showed that associations observed are unlikely to be explained by potential unmeasured confounding by lifestyle or other nutrients. Our results suggest that female urinary lignan concentrations at levels characteristic of the U.S. population are associated with a shorter TTP among couples who are attempting to conceive, highlighting the importance of dietary influences on fecundity. PMID:24401816

  7. Higher Education in Russia: Traditions and Modern Times (Report at the Seventh Congress of the Russian Union of Rectors)

    ERIC Educational Resources Information Center

    Sadovnichii, V.

    2004-01-01

    This article represents a speech delivered by the author at the Seventh Congress of the Russian Union of Rectors. In his address, the author describes the current higher educational trend in Russia. He explains how higher education's orientation toward the state, its openness to all social classes, and its fundamental character are the principles…

  8. Preparation of oil palm empty fruit bunch-based activated carbon for removal of 2,4,6-trichlorophenol: optimization using response surface methodology.

    PubMed

    Hameed, B H; Tan, I A W; Ahmad, A L

    2009-05-30

    The effects of three preparation variables: CO(2) activation temperature, CO(2) activation time and KOH:char impregnation ratio (IR) on the 2,4,6-trichlorophenol (2,4,6-TCP) uptake and carbon yield of the activated carbon prepared from oil palm empty fruit bunch (EFB) were investigated. Based on the central composite design, two quadratic models were developed to correlate the three preparation variables to the two responses. The activated carbon preparation conditions were optimized using response surface methodology by maximizing both the 2,4,6-TCP uptake and activated carbon yield within the ranges studied. The optimum conditions for preparing activated carbon from EFB for adsorption of 2,4,6-TCP were found as follows: CO(2) activation temperature of 814 degrees C, CO(2) activation time of 1.9h and IR of 2.8, which resulted in 168.89 mg/g of 2,4,6-TCP uptake and 17.96% of activated carbon yield. The experimental results obtained agreed satisfactorily with the model predictions. The activated carbon prepared under optimum conditions was mesoporous with BET surface area of 1141 m(2)/g, total pore volume of 0.6 cm(3)/g and average pore diameter of 2.5 nm. The surface morphology and functional groups of the activated carbon were respectively determined from the scanning electron microscopy and Fourier transform infrared analysis.

  9. SiH and the unidentified 4.6 micron feature

    NASA Technical Reports Server (NTRS)

    Nuth, Joseph A.; Moore, Marla H.

    1988-01-01

    Results from experimental studies of the irradiation of SiH4-H2O and Fe(CO)5-SiH4-H2O ice mixtures at 15 K using 1 MeV protons have revealed the synthesis of a very stable infrared spectral feature at 4.6 microns which is characteristic of the SiH functional group. This feature persists through warmup of the ice, exposure to air at 300 K, and vacuum annealing to at least 400 K. Because of the high cosmic abundance of both silicon and hydrogen and the unexpected stability of the SiH feature in our experiments, it is suggested that SiH might be responsible for the 4.6 micron absorption feature observed in W33A.

  10. CDK4/6 inhibitors in HER2-positive breast cancer.

    PubMed

    Corona, Silvia Paola; Ravelli, Andrea; Cretella, Daniele; Cappelletti, Maria Rosa; Zanotti, Laura; Dester, Martina; Gobbi, Angela; Petronini, Pier Giorgio; Generali, Daniele

    2017-04-01

    Notwithstanding the continuous progress made in cancer treatment in the last 20 years, and the availability of new targeted therapies, metastatic Breast Cancer (BC) is still incurable. Targeting the cell cycle machinery has emerged as an attractive strategy to tackle cancer progression, showing very promising results in the preclinical and clinical settings. The first selective inhibitors of CDK4/6 received breakthrough status and FDA approval in combination with letrozole (February 2015) and fulvestrant (February 2016) as first-line therapy in ER-positive advanced and metastatic BC. Considering the success of this family of compounds in hormone-positive BC, new possible applications are being investigated in other molecular subtypes. This review summarizes the latest findings on the use of CDK4/6 inhibitors in HER2 positive BC.

  11. Antibacterial activity of 2-(2',4'-dibromophenoxy)-4,6-dibromophenol from Dysidea granulosa.

    PubMed

    Shridhar, Divya M P; Mahajan, Girish B; Kamat, Vijayendra P; Naik, Chandrakant G; Parab, Rajashri R; Thakur, Nidhi R; Mishra, Prabhu D

    2009-09-22

    2-(2',4'-Dibromophenoxy)-4,6-dibromophenol isolated from the marine sponge Dysidea granulosa (Bergquist) collected off the coast of Lakshadweep islands, Indian Ocean, exhibited potent and broad spectrum in-vitro antibacterial activity, especially against methicillin resistant Staphylococcus aureus (MRSA), methicillin sensitive Staphylococcus aureus (MSSA), vancomycin resistant Enterococci (VRE), vancomycin sensitive Enterococci (VSE) and Bacillus spp. Minimal inhibitory concentration (MIC) was evaluated against 57 clinical and standard strains of Gram positive and Gram negative bacteria. The observed MIC range was 0.117-2.5 microg/mL against all the Gram positive bacteria and 0.5-2 microg/mL against Gram negative bacteria. The in-vitro antibacterial activity observed was better than that of the standard antibiotic linezolid, a marketed anti-MRSA drug. The results establish 2-(2',4'-dibromophenoxy)-4,6-dibromophenol, as a potential lead molecule for anti-MRSA and anti-VRE drug development.

  12. A large-scale evaluation of the KiVa antibullying program: grades 4-6.

    PubMed

    Kärnä, Antti; Voeten, Marinus; Little, Todd D; Poskiparta, Elisa; Kaljonen, Anne; Salmivalli, Christina

    2011-01-01

    This study demonstrates the effectiveness of the KiVa antibullying program using a large sample of 8,237 youth from Grades 4-6 (10-12 years). Altogether, 78 schools were randomly assigned to intervention (39 schools, 4,207 students) and control conditions (39 schools, 4,030 students). Multilevel regression analyses revealed that after 9 months of implementation, the intervention had consistent beneficial effects on 7 of the 11 dependent variables, including self- and peer-reported victimization and self-reported bullying. The results indicate that the KiVa program is effective in reducing school bullying and victimization in Grades 4-6. Despite some evidence against school-based interventions, the results suggest that well-conceived school-based programs can reduce victimization.

  13. Proton Relaxation in 1, 3, 5-Triamino-2, 4, 6-Trinitrobenzene (TATB).

    DTIC Science & Technology

    1980-06-16

    AD-AO? 209 NAVAL RESEARCH LAB WASHINGTON DC F/G 7/4 PROTON RELAXATION IN 1. 3, 5-TRIAMINO-2, 4. 6-TRINITROBENZENE C-ETC(Ul~JUN A0 A N GARROWAY , H A...TATB) 1 April - 31 September 1979 S. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(a) S. CONTRACT OR GRANT NUMBER(@) A.N. Garroway and H.A. Resing DE-AP-03

  14. Spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB

    DOEpatents

    Harris, Betty W.

    1986-01-01

    A simple, sensitive and specific spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB, is described. Upon the application of the composition of matter of the present invention to samples containing in excess of 0.1 mg of this explosive, a bright orange color results. Interfering species such as TNT and Tetryl can be removed by first treating the sample with a solvent which does not dissolve much of the TATB, but readily dissolves these explosives.

  15. Spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB

    DOEpatents

    Harris, B.W.

    1984-11-29

    A simple, sensitive and specific spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB, is described. Upon the application of the composition of matter of the subject invention to samples containing in excess of 0.1 mg of this explosive, a bright orange color results. Interfering species such as TNT and Tetryl can be removed by first treating the sample with a solvent which does not dissolve the TATB, but readily dissolves these interfering explosives.

  16. Temperature dependent structural, vibrational and magnetic properties of K3Gd5(PO4)6.

    PubMed

    Bevara, Samatha; Achary, S Nagabhusan; Mishra, Karuna Kara; Ravindran, T R; Sinha, Anil K; Sastry, P U; Tyagi, Avesh Kumar

    2017-02-22

    Herein we report the evolution of the crystal structure of K3Gd5(PO4)6 in the temperature range from 20 K to 1073 K, as observed from variable temperature X-ray diffraction and Raman spectroscopic studies. K3Gd5(PO4)6 has an open tunnel containing a three dimensional structure built by [Gd5(PO4)6](3-) ions which in turn are formed of PO4 tetrahedra and GdOn (n = 8 and 9) polyhedra. The empty tunnels in the structure are occupied by K(+) ions and maintain charge neutrality in the lattice. Evolution of unit cell parameters with temperature shows a systematic increase with temperature. The average axial thermal expansion coefficients between 20 K and 1073 K are: αa = 10.6 × 10(-6) K(-1), αb = 5.5 × 10(-6) K(-1) and αc = 16.4 × 10(-6) K(-1). The evolution of distortion indices of the various coordination polyhedra with temperature indicates a gradual decrease with increasing temperature, while those of Gd2O9 and K2O8 polyhedra show opposite trends. The overall anisotropy of the lattice thermal expansion is found to be controlled largely by the effect of temperature on GdOn polyhedra and their linkages. Temperature dependent Raman spectroscopic studies indicated that the intensities and wavenumbers of most of the Raman modes decrease continuously with increasing temperature. Anharmonic analyses of Raman modes indicated that the lattice, rigid translation and librational modes have larger contributions towards thermal expansion of K3Gd5(PO4)6 compared to high frequency internal modes. The temperature and field dependent magnetic measurements indicated no long range ordering down to 2 K and the observed effective magnetic moment per Gd(3+) ion and the Weiss constant are 7.91 μB and 0.38 K, respectively.

  17. Photoluminescent and magnetic properties of lanthanide containing apatites: NaxLn10-x(SiO4)6O2-yFy, CaxLn10-x(SiO4)6O2-yFy (Ln = Eu, Gd, and Sm), Gd9.34(SiO4)6O2, and K1.32Pr8.68(SiO4)6O1.36F0.64.

    PubMed

    Latshaw, Allison M; Hughey, Kendall D; Smith, Mark D; Yeon, Jeongho; Zur Loye, Hans-Conrad

    2015-02-02

    Single crystals of NaEu(9)(SiO(4))(6)O(2), Na(1.5)Eu(8.5)(SiO(4))(6)OF, Na(1.64)Gd(8.36)(SiO(4))(6)O(0.72)F(1.28), Gd(9.34)(SiO(4))(6)O(2), Ca(2.6)Eu(7.4)(SiO(4))(6)O(1.4)F(0.6), Ca(4.02)Sm(5.98)(SiO(4))(6)F(2), and K(1.32)Pr(8.68)(SiO(4))(6)O(1.36)F(0.64) and powders of NaEu(9)(SiO(4))(6)O(2), Na(1.5)Eu(8.5)(SiO(4))(6)OF, Eu(9.34)(SiO(4))(6)O(2), and Gd(9.34)(SiO(4))(6)O(2) were synthesized via flux growth in selected alkali-fluoride melts. All of the compounds adopt the apatite structure with space group P6(3)/m. Luminescence and magnetic data were collected on NaEu(9)(SiO(4))(6)O(2), Na(1.5)Eu(8.5)(SiO(4))(6)OF, Eu(9.34)(SiO(4))(6)O(2), and Gd(9.34)(SiO(4))(6)O(2). Luminescent data indicate that changing the cations and anions that surround the lanthanide site does not change the luminescent properties, making apatites versatile structures for optical materials.

  18. New double molybdate Na9Fe(MoO4)6: Synthesis, structure, properties

    NASA Astrophysics Data System (ADS)

    Savina, Aleksandra A.; Solodovnikov, Sergey F.; Basovich, Olga M.; Solodovnikova, Zoya A.; Belov, Dmitry A.; Pokholok, Konstantin V.; Gudkova, Irina A.; Stefanovich, Sergey Yu.; Lazoryak, Bogdan I.; Khaikina, Elena G.

    2013-09-01

    A new double molybdate Na9Fe(MoO4)6 was synthesized using solid state reactions and studied with X-ray powder diffraction, second harmonic generation (SHG) technique, differential scanning calorimetry, X-ray fluorescence analysis, Mössbauer and dielectric impedance spectroscopy. Single crystals of Na9Fe(MoO4)6 were obtained and its structure was solved (the space group R3¯, a=14.8264(2), c=19.2402(3) Å, V=3662.79(9) Å3, Z=6, R=0.0132). The structure is related to that of sodium ion conductor II-Na3Fe2(AsO4)3. The basic structure units are polyhedral clusters composed of central FeО6 octahedron sharing edges with three Na(1)О6 octahedra. The clusters share common vertices with bridging МоО4 tetrahedra to form an open 3D framework where the cavities are occupied by Na(2) and Na(3) atoms. The compound melts incongruently at 904.7±0.2 K. Arrhenius type temperature dependence of electric conductivity σ has been registered in solid state (σ=6.8×10-2 S сm-1 at 800 K), thus allowing considering Na9Fe(MoO4)6 as a new sodium ion conductor.

  19. Inhibition of CDK4/6 protects against radiation-induced intestinal injury in mice

    PubMed Central

    Wei, Liang; Leibowitz, Brian J.; Wang, Xinwei; Epperly, Michael; Greenberger, Joel; Zhang, Lin

    2016-01-01

    Radiotherapy causes dose-limiting toxicity and long-term complications in rapidly renewing tissues, including the gastrointestinal tract. Currently, there is no FDA-approved agent for the prevention or treatment of radiation-induced intestinal injury. In this study, we have shown that PD 0332991 (PD), an FDA-approved selective inhibitor of cyclin-dependent kinase 4/6 (CDK4/6), prevents radiation-induced lethal intestinal injury in mice. Treating mice with PD or a structurally distinct CDK4/6 inhibitor prior to radiation blocked proliferation and crypt apoptosis and improved crypt regeneration. PD treatment also enhanced LGR5+ stem cell survival and regeneration after radiation. PD was an on-target inhibitor of RB phosphorylation and blocked G1/S transition in the intestinal crypts. PD treatment strongly but reversibly inhibited radiation-induced p53 activation, which blocked p53-upregulated modulator of apoptosis–dependent (PUMA-dependent) apoptosis without affecting p21-dependent suppression of DNA damage accumulation, with a repair bias toward nonhomologous end joining. Further, deletion of PUMA synergized with PD treatment for even greater intestinal radioprotection. Our results demonstrate that the cell cycle critically regulates the DNA damage response and survival of intestinal stem cells and support the concept that pharmacological quiescence is a potentially highly effective and selective strategy for intestinal radioprotection. PMID:27701148

  20. 2,4,6-Trichloroanisole is a potent suppressor of olfactory signal transduction

    PubMed Central

    Takeuchi, Hiroko; Kato, Hiroyuki; Kurahashi, Takashi

    2013-01-01

    We investigated the sensitivity of single olfactory receptor cells to 2,4,6-trichloroanisole (TCA), a compound known for causing cork taint in wines. Such off-flavors have been thought to originate from unpleasant odor qualities evoked by contaminants. However, we here show that TCA attenuates olfactory transduction by suppressing cyclic nucleotide-gated channels, without evoking odorant responses. Surprisingly, suppression was observed even at extremely low (i.e., attomolar) TCA concentrations. The high sensitivity to TCA was associated with temporal integration of the suppression effect. We confirmed that potent suppression by TCA and similar compounds was correlated with their lipophilicity, as quantified by the partition coefficient at octanol/water boundary (pH 7.4), suggesting that channel suppression is mediated by a partitioning of TCA into the lipid bilayer of plasma membranes. The rank order of suppression matched human recognition of off-flavors: TCA equivalent to 2,4,6-tribromoanisole, which is much greater than 2,4,6-trichlorophenol. Furthermore, TCA was detected in a wide variety of foods and beverages surveyed for odor losses. Our findings demonstrate a potential molecular mechanism for the reduction of flavor. PMID:24043819

  1. Educational Family Background and the Realisation of Educational Career Intentions: Participation of German Upper Secondary Graduates in Higher Education over Time

    ERIC Educational Resources Information Center

    Weiss, Felix; Steininger, Hanna-Marei

    2013-01-01

    In this article, we evaluate the impact of social origin on the realisation of educational intentions at the time of becoming eligible for higher education in Germany. In general, we find high persistence of intentions and actual attendance of higher education. However, effects of parental education on the changes of educational intentions…

  2. Salaries, Tenure, and Fringe Benefits of Full-Time Instructional Faculty. Higher Education General Information Survey (HEGIS) [machine-readable data file].

    ERIC Educational Resources Information Center

    VSE Corp., Alexandria, VA.

    The "Faculty Salary Survey" machine-readable data file (MRDF) is one component of the Higher Education General Information Survey (HEGIS). It contains data about salaries, tenure, and fringe benefits for full-time instructional faculty from over 3,000 institutions of higher education located in the United States and its outlying areas.…

  3. Supercritical fluid extraction of 2,4,6-trinitrotoluene and 1,3,5-trinitrobenzene from soil

    SciTech Connect

    Wujcik, C.E.; Seiber, J.N.

    1996-07-01

    Optimization of a methanol-modified supercritical fluid extraction (SFE) technique using carbon dioxide has resulted in the effective recovery of 2,4,6-trinitrotoluene (TNT) and 1,3,5-trinitrobenzene (TNB) from spiked and native soils. Several parameters, including modifier concentration, temperature, density, and static and dynamic extraction time were varied independently to determine the effect of each on analyte recovery. The optimal SFE conditions are: 5% methanol, 150{degree}C, 7500 PSI, 5 minutes static extraction and 15 minutes dynamic extraction. Samples were analyzed by gas chromatography using electron-capture detection (ECD). SFE quantitatively recovered both TNT and TNB from the soil matrix in considerably less time than conventional Soxhlet extraction with ethyl acetate and sonication with acetonitrile. 12 refs., 4 figs., 5 tabs.

  4. Oxidative degradation of 2,4-xylidine by photosensitization with 2,4,6-triphenylpyrylium: homogeneous and heterogeneous catalysis.

    PubMed

    Amat, Ana M; Arques, Antonio; Bossmann, Stefan H; Braun, André M; Göb, Sabine; Miranda, Miguel A; Oliveros, Esther

    2004-12-01

    The possibility of using zeolites containing the 2,4,6-triphenylpyrylium cation as photocatalysts for the degradation of pollutants has been tested on aqueous xylidine (2,4-dimethylaniline) solutions as models for contaminated wastewaters. The influence of the photocatalyst and substrate concentrations on xylidine oxidation has been investigated in homogeneous solution, by performing a series of experiments chosen according to the experimental design methodology (Doehlert uniform array). The empirical models and the corresponding response surfaces obtained from data analysis have been used for simulating and predicting degradation efficiency. The results have shown that conversion increases with increasing amounts of photocatalyst and decreasing concentration of the model pollutant. The fluorescence of 2,4,6-triphenylpyrylium was quenched by xylidine with a rate constant k(q) of 3.1x10(9)M(-1)s(-1). This result suggests a direct electron transfer between the excited pyrylium salt and xylidine. Because of the limited stability of the photocatalyst in homogeneous media, a pyrylium containing Y-zeolite has been tested for the photocatalytic oxidation of xylidine under heterogeneous conditions. The results suggest that the supported catalyst has a much improved stability and that xylidine oxidation rates remain nearly constant during the whole reaction time. An additional advantage of the pyrylium containing zeolite photocatalyst is that it can be recycled and used for further experiments.

  5. Broadband Yellowish-Green Emitting Ba4Gd3Na3(PO4)6F2:Eu(2+) Phosphor: Structure Refinement, Energy Transfer, and Thermal Stability.

    PubMed

    Fu, Xiaopeng; Lü, Wei; Jiao, Mengmeng; You, Hongpeng

    2016-06-20

    A series of Ba4Gd3Na3(PO4)6F2:Eu(2+) phosphors with a broad emitting band have been synthesized by a traditional solid state reaction. The crystal structural and photoluminescence properties of Ba4Gd3Na3(PO4)6F2:Eu(2+) are investigated. The different crystallographic sites of Eu(2+) in Ba4Gd3Na3(PO4)6F2:Eu(2+) phosphors have been verified by means of their photoluminescence (PL) properties and decay times. Energy transfer between Eu(2+) ions, analyzed by excitation, emission, and PL decay behavior, has been indicated to be a dipole-dipole mechanism. Moreover, the luminescence quantum yield as well as the thermal stability of the Ba4Gd3Na3(PO4)6F2:Eu(2+) phosphor have been investigated systematically. The as-prepared Ba4Gd3Na3(PO4)6F2:Eu(2+) phosphor can act as a promising candidate for n-UV convertible white LEDs.

  6. A Call to Action on New England's Innovation Economy: Will Business and Higher Education Answer This Time?

    ERIC Educational Resources Information Center

    Guenther, William

    2003-01-01

    Mass Insight Corp, a public policy and communications firm that organizes public-private initiatives to support economic growth in Massachusetts, recently issued a new report, titled "An Economy at Risk," making the case for a Massachusetts economic development strategy organized around higher education and science and technology.…

  7. Australian Higher Education Leaders in Times of Change: The Role of Pro Vice-Chancellor and Deputy Vice-Chancellor

    ERIC Educational Resources Information Center

    Scott, Geoff; Bell, Sharon; Coates, Hamish; Grebennikov, Leonid

    2010-01-01

    This paper discusses responses provided by 31 Pro Vice-Chancellors (PVCs) and Deputy Vice-Chancellors (DVCs) who were part of a larger study of more than 500 higher education leaders in roles ranging from DVC to head of programme in 20 Australian universities. Using both quantitative and qualitative data the paper gives an insider's perspective on…

  8. A Lesson of Lost Political Capital in Public Higher Education: Leadership Challenges in a Time of Needed Organizational Change

    ERIC Educational Resources Information Center

    Hilton, Mark; Jacobson, Rod

    2012-01-01

    All higher education institutions are struggling with a rapidly changing market and financial landscape. Here is a management-centered analysis of what happened when a college president, recognizing the need to make a radical adaptation to those changes, tried moving a campus community to a new organizational model, without collegial consensus,…

  9. Breaking the Mold: New Approaches for Higher Education in Tough Economic Times. Complete to Compete Briefing Paper

    ERIC Educational Resources Information Center

    Carey, Kevin

    2011-01-01

    Human capital is the key to economic development. Without highly-skilled workers, states and territories cannot attract the productive businesses they need. That makes higher education a key element of any governor's growth strategy. But many public colleges and universities are struggling to produce more graduates. Overall graduation rates often…

  10. Funding System of Full-Time Higher Education and Technical Efficiency: Case of the University of Ljubljana

    ERIC Educational Resources Information Center

    Tajnikar, Maks; Debevec, Jasmina

    2008-01-01

    The present paper tackles the issue of the higher education funding system in Slovenia. Its main attribute is that institutions are classified into study groups according to their fields of education, and funds granted by the state are based on their weights or study group factors (SGF). Analysis conducted using data envelopment analysis tested…

  11. Applying the Modality Principle to Real-Time Feedback and the Acquisition of Higher-Order Cognitive Skills

    ERIC Educational Resources Information Center

    Fiorella, Logan; Vogel-Walcutt, Jennifer J.; Schatz, Sae

    2012-01-01

    Effectively presenting complex material is a crucial component of instructional design within simulation-based training (SBT) environments. One approach to facilitate the acquisition of higher-order knowledge is to embed instructional strategies within the systems themselves. Currently, however, there are few established guidelines to inform…

  12. Unprecedented Times in the Professionalisation and State Regulation of Counselling and Psychotherapy: The Role of the Higher Education Institute

    ERIC Educational Resources Information Center

    Murphy, David

    2011-01-01

    This article considers a number of issues facing those involved in counselling and psychotherapy training within United Kingdom Higher Education Institutes. It is proposed that the increasing professionalisation of counselling and psychotherapy has significant implications for lecturers and trainers. The article will explore the tension between…

  13. Quality after the Cuts? Higher Education Practitioners' Accounts of Systemic Challenges to Teaching Quality in Times of "Austerity"

    ERIC Educational Resources Information Center

    Feigenbaum, Anna; Iqani, Mehita

    2015-01-01

    What are the ramifications of current changes in the higher education landscape in the UK for the ways in which teaching staff perceive their teaching practices? What impact are funding cuts, increases in student fees and the concomitant increased workloads having on faculty morale? How might this influence "quality cultures" in teaching…

  14. Universities' Autonomy in Times of Changing Higher Education Governance: A Study of the Swiss Academic Labour Market

    ERIC Educational Resources Information Center

    Baschung, Lukas; Goastellec, Gaele; Leresche, Jean-Philippe

    2011-01-01

    Although eternally debated, the issue of autonomy in higher education is rarely analysed in its complexity. To address this issue, this article uses an analytical matrix which combines the distinction between substantive and procedural autonomy and the distinction between HEI governing bodies, academic professions and individual academics. This…

  15. Just-in-Time Research: A Call to Arms for Research into Mobile Technologies in Higher Education

    ERIC Educational Resources Information Center

    Byrne-Davis, Lucie; Dexter, Hilary; Hart, Jo; Cappelli, Tim; Byrne, Ged; Sampson, Ian; Mooney, Jane; Lumsden, Colin

    2015-01-01

    Mobile technologies are becoming commonplace in society and in education. In higher education, it is crucial to understand the impact of constant access to information on the development of the knowledge and competence of the learner. This study reports on a series of four surveys completed by UK-based medical students (n = 443) who received…

  16. Residence and Migration of First-Time Freshmen Enrolled in Higher Education Institutions: Fall 1994. E.D. TABS.

    ERIC Educational Resources Information Center

    Barbett, Samuel

    This report presents 23 tables of data on residence and migration of first-time freshmen based on the 1994 "Fall Enrollment" survey, part of the Integrated Postsecondary Education Data System. The survey counted 2.14 million first-time freshmen. More than 366,000 (17 percent) migrated between states. The percent of freshmen who left…

  17. Examining the Potential Impact of Full Tuition Fees on Mature Part-Time Students in English Higher Education

    ERIC Educational Resources Information Center

    Shaw, Angela

    2014-01-01

    This paper examines current part-time mature learners' views on the potential impact upon future students as full fees are introduced from 2012. It investigates the problems which part-time mature learners may face with the advent of student loans and subsequent debt, given that they are usually combining complex lives with their studies, with…

  18. CDK4/6 inhibition induces epithelial cell cycle arrest and ameliorates acute kidney injury

    PubMed Central

    DiRocco, Derek P.; Bisi, John; Roberts, Patrick; Strum, Jay; Wong, Kwok-Kin; Sharpless, Norman

    2013-01-01

    Acute kidney injury (AKI) is common and urgently requires new preventative therapies. Expression of a cyclin-dependent kinase (CDK) inhibitor transgene protects against AKI, suggesting that manipulating the tubular epithelial cell cycle may be a viable therapeutic strategy. Broad spectrum small molecule CDK inhibitors are protective in some kidney injury models, but these have toxicities and epithelial proliferation is eventually required for renal repair. Here, we tested a well-tolerated, novel and specific small molecule inhibitor of CDK4 and CDK6, PD 0332991, to investigate the effects of transient cell cycle inhibition on epithelial survival in vitro and kidney injury in vivo. We report that CDK4/6 inhibition induced G0/G1 cycle arrest in cultured human renal proximal tubule cells (hRPTC) at baseline and after injury. Induction of transient G0/G1 cycle arrest through CDK4/6 inhibition protected hRPTC from DNA damage and caspase 3/7 activation following exposure to the nephrotoxins cisplatin, etoposide, and antimycin A. In vivo, mice treated with PD 0332991 before ischemia-reperfusion injury (IRI) exhibited dramatically reduced epithelial progression through S phase 24 h after IRI. Despite reduced epithelial proliferation, PD 0332991 ameliorated kidney injury as reflected by improved serum creatinine and blood urea nitrogen levels 24 h after injury. Inflammatory markers and macrophage infiltration were significantly decreased in injured kidneys 3 days following IRI. These results indicate that induction of proximal tubule cell cycle arrest with specific CDK4/6 inhibitors, or “pharmacological quiescence,” represents a novel strategy to prevent AKI. PMID:24338822

  19. Reduction of the explosive 2,4,6-trinitrotoluene by enzymes from aquatic sediments

    SciTech Connect

    Beelen, P. van; Burris, D.R.

    1995-12-01

    Enzymes were extracted from aquatic sediments. Some of these enzymes reduced 2,4,6-trinitrotoluene (TNT) with nicotinamide adenosine dinucleotide phosphate (NADPH) as an electron donor under aerobic conditions. The origin of these enzymes was not clear as the enzymes were extracted from a sediment containing plant roots and microorganisms. Aquatic plants were determined to e a source of TNT-reducing enzymes. Chemical reduction was not a rate-limiting process in the assays as the enzymatic activity was inhibited by heating or the addition of proteases. Enzymatic activity in the extracts was further characterized. Partial purifications of enzymes from the sediment extracts shows that several proteins capable of reducing NT with NADPH were present. The enzymes did not require flavins and preferred NADPH over NADH as the electron donor. The pH optimum for the stability of the enzymes was near neutral, and the temperature optimum was in the 37 to 45 C range. Addition of dithiothreitol improved the stability of the enzymes. The enzymes reduced 2,4,6-trinitrotoluene to 2-amino-4,6-dinitrotoluene, 4-amino-2,6-dinitrotoluene, 2,4-diamino-6-nitrotoluene, and 2,6-diamino-4-nitrotoluene under aerobic conditions with NADPH. When used as a starting substrate, the aminodinitrotoluenes were not reduced by the enzymes. It might be possible that the hydroxylaminodinitrotoluenes are reduced to di[hydroxylamine]nitrotoluenes prior to the formation of the diaminonitrotoluenes. Sediments from 11 surface water bodies were examined for the presence of TNT-reducing enzymes, and 10 were found to have activity. These enzymes appear to be ubiquitous and are present in both freshwater and saltwater sediments. Reduction of TNT by sediment enzymes can be a significant environmental fate process for TNT in aquatic systems.

  20. Maintaining Quality in Troubled Times. Pacific Rim Association for Higher Education Annual Conference (2nd, Seattle, Washington, October 13-14, 1981).

    ERIC Educational Resources Information Center

    Pacific Rim Association for Higher Education.

    Proceedings of the Pacific Rim Association for Higher Education 1981 conference are summarized. Authors and the summarized papers are as follows: "Maintaining Quality in Troubled Times: The University Perspective" (George M. Beckmann); "Maintaining Quality in Troubled Times: The Community College Perspective" (Don A. Morgan);…

  1. The Hidden Benefits of Part-Time Higher Education Study to Working Practices: Is There a Case for Making Them More Visible?

    ERIC Educational Resources Information Center

    Callender, Claire; Little, Brenda

    2015-01-01

    Within the UK, part-time study is now seen as important in meeting wider government objectives for higher education (HE) and for sustainable economic growth through skills development. Yet, measures to capture the impact of HE may not be wholly appropriate to part-time study. In particular, the continuing focus on tangible, economic measures may…

  2. An optimization-based approach for solving a time-harmonic multiphysical wave problem with higher-order schemes

    NASA Astrophysics Data System (ADS)

    Mönkölä, Sanna

    2013-06-01

    This study considers developing numerical solution techniques for the computer simulations of time-harmonic fluid-structure interaction between acoustic and elastic waves. The focus is on the efficiency of an iterative solution method based on a controllability approach and spectral elements. We concentrate on the model, in which the acoustic waves in the fluid domain are modeled by using the velocity potential and the elastic waves in the structure domain are modeled by using displacement. Traditionally, the complex-valued time-harmonic equations are used for solving the time-harmonic problems. Instead of that, we focus on finding periodic solutions without solving the time-harmonic problems directly. The time-dependent equations can be simulated with respect to time until a time-harmonic solution is reached, but the approach suffers from poor convergence. To overcome this challenge, we follow the approach first suggested and developed for the acoustic wave equations by Bristeau, Glowinski, and Périaux. Thus, we accelerate the convergence rate by employing a controllability method. The problem is formulated as a least-squares optimization problem, which is solved with the conjugate gradient (CG) algorithm. Computation of the gradient of the functional is done directly for the discretized problem. A graph-based multigrid method is used for preconditioning the CG algorithm.

  3. Synthesis and crystal structure of a dinuclear yttrium(III)- (lanthanide(III)-) copper(II) complex with an unusual 2-methyl-2,4,6-tris(trifluoromethyl)-1,3-dioxane-4,6-diolato ligand

    SciTech Connect

    Wang, S.; Pang, Z.; Smith, K.D.L. )

    1993-11-10

    A dinuclear Ln[sup III]-Cu[sup II] complex with an unusual 2-methyl-2,4,6-tris(trifluoromethyl)-1,3-dioxane-4,6-diolato ligand has been synthesized and characterized structurally. The 1,3-dioxane-4,6-diolato ligand is the product of cycloaddition of 1,1,1-trifluoro-2,2-propanediol to a hexafluoroacetylacetonato ligand promoted by the metal complex.

  4. (Z)-Ethyl 3-(2,4,6-trimethyl­anilino)but-2-enoate

    PubMed Central

    Amézquita-Valencia, Manuel; Hernández-Ortega, Simón; Suárez-Ortiz, G. Alejandra; Toscano, Rubén Alfredo; Cabrera, Armando

    2009-01-01

    The title compound, C15H21NO2, was obtained by the reaction of acetoacetate with 2,4,6-trimethyl­aniline using Mexican bentonitic clay as a catalyst. It crystallizes in the enamine form. The β-enamino ester residue is almost perpendicular to the aromatic ring [dihedral angle = 88.10 (6)°]. The mol­ecular conformation is stabilized by a strong intra­molecular N—H⋯O hydrogen bond. In addition, the N—H group forms a weak inter­molecular N—H⋯O hydrogen bond linking the mol­ecules into centrosymmetric dimers. PMID:21578324

  5. Microbial Transformation of 2,4,6-Trinitrotoluene in Aerobic Soil Columns

    PubMed Central

    Bruns-Nagel, D.; Breitung, J.; von Low, E.; Steinbach, K.; Gorontzy, T.; Kahl, M.; Blotevogel, K.; Gemsa, D.

    1996-01-01

    2,4,6-Trinitrotoluene (TNT)-contaminated soil material of a former TNT production plant was percolated aerobically in soil columns. Nineteen days of percolation with a potassium phosphate buffer supplemented with glucose or glucose plus ammonium sulfate caused an over 90% decline in the amount of extractable nitroaromatics in soils containing 70 to 2,100 mg of TNT per kg (dry weight). In the percolation solution, a complete elimination of TNT was achieved. Mutagenicity and soil toxicity were significantly reduced by the percolation process. 4-N-Acetylamino-2-amino-6-nitrotoluene was generated in soil and percolation fluid as a labile TNT metabolite. PMID:16535369

  6. Mechanistic insights into the stepwise Diels-Alder reaction of 4,6-dinitrobenzofuroxan.

    PubMed

    Linder, Mats; Johansson, Adam Johannes; Brinck, Tore

    2012-01-06

    The stepwise Diels-Alder reaction between 1-trimethylsiloxy-1,3-butadiene and 4,6-dinitrobenzofuroxan is explored using state-of-the-art computational methods. The results support a stepwise mechanism via a persistent intermediate, however, not the one previously reported (Lakhdar et al., Chem. Eur. J.2007, 16, 5681) but a heterocyclic adduct. The novel DFT functional M062X and the SCS-MP2 method were essential to reproduce a reasonable potential energy surface for this challenging system.

  7. n-Propyl 2,3,4,6-tetra-O-acetyl-β-d-glucopyran-oside.

    PubMed

    Mönch, Bettina; Emmerling, Franziska; Kraus, Werner; Becker, Roland; Nehls, Irene

    2013-02-01

    THE TITLE COMPOUND [SYSTEMATIC NAME: (2R,3R,4S,5R,6R)-2-(acet-oxy-meth-yl)-6-propoxytetra-hydro-2H-pyran-3,4,5-triyl triacetate], C(17)H(26)O(10), was formed by a Koenigs-Knorr reaction of 2,3,4,6-tetra-O-acetyl-α-d-glucopyranosyl bromide and n-propanol. The central ring adopts a chair conformation. The crystal does not contain any significant inter-actions such as hydrogen bonds.

  8. Synthesis, loading control and applications of 2,4,6-triphenylpyrilium as a solar photocatalyst

    NASA Astrophysics Data System (ADS)

    Vercher Perez, Rosa

    2005-07-01

    The technologies or processes of oxidation outpost that uses like energy the solar radiation for the degradation of polluting agents, suppose a novel alternative with important economic and environmental advantages. A proof of it has been the spectacular development which they have been these applications at world-wide level in the last years old, as well as the interest that the subject in international the scientific community has provoked. 2,4,6-trifenilpirilio by its singularity in this field has been chosen for this thesis the cation. It has been left from a study about the fotocatalitica activity of this cation, from the salt of hidrogenosulfato 2,4,6-trifenilpirilio and of the salt of tetrafluorborato 2,4,6-trifenilpirilio, when they act in homogenous phase on polluting agents, derivatives of dissolved fenolicos compounds in residual coming from the industry. In the first stage of the study I confirm the degradativo power of this cation but nevertheless a series of disadvantages in homogena phase was detected, had to the chemical characteristics of this organic species: hidrolitica opening of the ring and impossibility of reusability. With the purpose of correcting these problems it has been investigated and developed different methods from synthesis, in which this cation is supported in inorganic materials, concretely: silica gel, zeolites and sepiolitas. It has been come to the study, of individual form, the parameters that influence of significant form in the yield of the different processes and also has been verified the fotocatalitica activity of the new synthesized materials. In the developed methods it has been managed to totally control the amount of cation supported in the chosen materials and of this form to be able to know the effectiveness his activity like fotocatalizador in heterogenous phase. It is possible to emphasize, that the proposed procedures of synthesis, are quite simple and fast in his execution. The made studies have been carried

  9. UV photolysis for enhanced phenol biodegradation in the presence of 2,4,6-trichlorophenol (TCP).

    PubMed

    Song, Jiaxiu; Wang, Wenbing; Li, Rongjie; Zhu, Jun; Zhang, Yongming; Liu, Rui; Rittmann, Bruce E

    2016-02-01

    A bacterial strain isolated from activated sludge and identified as Bacillus amyloliquefaciens could biodegrade phenol, but 2,4,6-trichlorophenol (TCP) inhibited phenol biodegradation and biomass growth. UV photolysis converted TCP into dichlorocatechol, monochlorophenol, and dichlorophenol, and this relieved inhibition by TCP. Phenol-removal and biomass-growth rates were significantly accelerated after UV photolysis: the monod maximum specific growth rate (μ(max)) increased by 9% after TCP photolysis, and the half-maximum-rate concentration (K(S)) decreased by 36%. Thus, the major benefit of UV photolysis in this case was to transform TCP into a set of much-less-inhibitory products.

  10. Tangent Adjoint Methods In a Higher-Order Space-Time Discontinuous-Galerkin Solver For Turbulent Flows

    NASA Technical Reports Server (NTRS)

    Diosady, Laslo; Murman, Scott; Blonigan, Patrick; Garai, Anirban

    2017-01-01

    Presented space-time adjoint solver for turbulent compressible flows. Confirmed failure of traditional sensitivity methods for chaotic flows. Assessed rate of exponential growth of adjoint for practical 3D turbulent simulation. Demonstrated failure of short-window sensitivity approximations.

  11. Smartphone-based portable biosensing system using impedance measurement with printed electrodes for 2,4,6-trinitrotoluene (TNT) detection.

    PubMed

    Zhang, Diming; Jiang, Jing; Chen, Junye; Zhang, Qian; Lu, Yanli; Yao, Yao; Li, Shuang; Logan Liu, Gang; Liu, Qingjun

    2015-08-15

    Rapid, sensitive, selective and portable detection of 2,4,6-trinitrotoluene (TNT) is in high demand for public safety and environmental monitoring. In this study, we reported a smartphone-based system using impedance monitoring for TNT detection. The screen-printed electrodes modified with TNT-specific peptides were used as disposable a biosensor to produce impedance responses to TNT. The responses could be monitored by a hand-held device and send out to smartphone through Bluetooth. Then, the smartphone was used to display TNT responses in real time and report concentration finally. In the measurement, the system was demonstrated to detect TNT at concentration as low as 10(-6) M and distinguish TNT versus different chemicals in high specificity. Thus, the smartphone-based biosensing platform provided a convenient and efficient approach to design portable instruments for chemical detections such as TNT recognition.

  12. The fluorophore 4',6-diamidino-2-phenylindole (DAPI) induces DNA folding in long double-stranded DNA.

    PubMed

    Beccia, Maria Rosa; Biver, Tarita; Pardini, Alberto; Spinelli, Jacopo; Secco, Fernando; Venturini, Marcella; Busto Vázquez, Natalia; Lopez Cornejo, Maria Pilar; Martin Herrera, Victoria Isabel; Prado Gotor, Rafael

    2012-08-01

    DAPI (4',6-diamidino-2-phenylindole) is a widely used fluorescent dye, whose complicated binding features to DNAs and RNAs have been the object of debates and are still not fully understood. In this study, different approaches were employed, including binding equilibrium measurements (spectrofluorometry), melting experiments (spectrophotometry), viscometric measurements, circular dichroism, and T-jump kinetic analyses; all data concur in shedding light on the complex mechanistic aspects of the binding mode of DAPI to natural DNA. Conditions are found that induce the mode of the DAPI/DNA interaction to change from groove binding to intercalation. Moreover, it is observed, for the first time, that DAPI is able to induce the formation of a rather compact polymer-dye adduct under particular conditions. The results suggest that this form is a folded or coiled DNA structure stabilized by DAPI dye bridges.

  13. Proton radii of {sup 4,6,8}He isotopes from high-precision nucleon-nucleon interactions

    SciTech Connect

    Caurier, E.; Navratil, P.

    2006-02-15

    Recently, precision laser spectroscopy on {sup 6}He atoms determined accurately the isotope shift between {sup 4}He and {sup 6}He and, consequently, the charge radius of {sup 6}He. A similar experiment for {sup 8}He is under way. We have performed large-scale ab initio calculations for {sup 4,6,8}He isotopes using high-precision nucleon-nucleon (NN) interactions within the no-core shell model (NCSM) approach. With the CD-Bonn 2000 NN potential we found point-proton root-mean-square (rms) radii of {sup 4}He and {sup 6}He 1.45(1) fm and 1.89(4), respectively, in agreement with experiment and predict the {sup 8}He point-proton rms radius to be 1.88(6) fm. At the same time, our calculations show that the recently developed nonlocal INOY NN potential gives binding energies closer to experiment, but underestimates the charge radii.

  14. Concentrations of organochlorine pesticides and 2,4,6-trichloroanisole in cork bark.

    PubMed

    Olivella, M Àngels; Caixach, Josep; Planas, Carles; Oliveras, Anna; Jové, Patrícia

    2012-02-01

    Organochlorine pesticides are persistent lipophilic organic pollutants and tend to accumulate in growing plants. During growth, cork is in contact with the open air for long periods (9-12 years). Owing to the previous widespread use of organochlorine pesticides and their high persistence in the environment, there is a risk that residues of such pesticides may be present in cork. In this study, the concentrations of 14 organochlorine pesticides-all of which are indicators of environmental pollution-were analyzed in cork bark samples from three regions in Spain and one in Portugal. In addition, the concentrations of 2,4,6-trichlorophenol (TCP) and 2,4,6-trichloroanisole (TCA) were also analyzed. Our results show only very low concentrations of lindane, γ-HCH (<2.6 ng g(-1)) and its byproducts α-HCH (<3.5 ng g(-1)) and β-HCH (<0.6 ng g(-1)). Among the DDT and its metabolites, only two were found: p,p'-DDT was found in a cork sample from Extremadura (0.1 ng g(-1)) and p,p'-DDE was present at a maximum concentration of 2.9 ng g(-1) in a cork sample from Castile-La Mancha. However, all concentrations were well below the legal limit established by Regulation (EC) No. 396/2005 (10 ng g(-1) in foodstuffs). We can conclude, therefore, that the cork samples we studied complied with food safety standards.

  15. 2,4,6-Trinitrotoluene reduction by carbon monoxide dehydrogenase from Clostridium thermoaceticum

    SciTech Connect

    Huang, S.; Lindahl, P.A.; Wang, C.; Bennett, G.N.; Rudolph, F.B.; Hughes, J.B.

    2000-03-01

    Purified CO dehydrogenase (CODH) from Clostridium thermoaceticum catalyzed the transformation of 2,4,6-trinitrotoluene (TNT). The intermediates and reduced products of TNT transformation were separated and appear to be identical to the compounds formed by C. acetobutylicum, namely, 2-hydroxylamino-4,6-dinitrotoluene (2 HA46DNT), 4-hydroxylamino-2,6-dinitrotoluene (4HA26DNT), 2,4-dihydroxylamino-6-nitrotoluene (24DHANT), and the Bamberger rearrangement product of 2,4-dihydroxylamino-6-nitrotoluene. In the presence of saturating CO, CODH catalyzed the conversion of TNT to two monohydroxylamino derivatives (2HA46DNT and 4HA26DNT), with 4HA26DNT as the dominant isomer. These derivatives were then converted to 24DHANT, which slowly converted to the Bamberger rearrangement product. Apparent K{sub m} and k{sub cat} values of TNT reduction were 165 {+-} 43 {micro}M for TNT and 400 {+-} 94 s{sup {minus}1}, respectively. Cyanide, an inhibitor for the CO/CO{sub 2} oxidation/reduction activity of CODH, inhibited the TNT degradation activity of CODH.

  16. 2,4,6-trinitrotoluene reduction by carbon monoxide dehydrogenase from Clostridium thermoaceticum.

    PubMed

    Huang, S; Lindahl, P A; Wang, C; Bennett, G N; Rudolph, F B; Hughes, J B

    2000-04-01

    Purified CO dehydrogenase (CODH) from Clostridium thermoaceticum catalyzed the transformation of 2,4,6-trinitrotoluene (TNT). The intermediates and reduced products of TNT transformation were separated and appear to be identical to the compounds formed by C. acetobutylicum, namely, 2-hydroxylamino-4,6-dinitrotoluene (2HA46DNT), 4-hydroxylamino-2,6-dinitrotoluene (4HA26DNT), 2, 4-dihydroxylamino-6-nitrotoluene (24DHANT), and the Bamberger rearrangement product of 2,4-dihydroxylamino-6-nitrotoluene. In the presence of saturating CO, CODH catalyzed the conversion of TNT to two monohydroxylamino derivatives (2HA46DNT and 4HA26DNT), with 4HA26DNT as the dominant isomer. These derivatives were then converted to 24DHANT, which slowly converted to the Bamberger rearrangement product. Apparent K(m) and k(cat) values of TNT reduction were 165 +/- 43 microM for TNT and 400 +/- 94 s(-1), respectively. Cyanide, an inhibitor for the CO/CO(2) oxidation/reduction activity of CODH, inhibited the TNT degradation activity of CODH.

  17. Chemically catalyzed uptake of 2,4,6-trinitrotoluene by Vetiveria zizanioides.

    PubMed

    Makris, Konstantinos C; Shakya, Kabindra M; Datta, Rupali; Sarkar, Dibyendu; Pachanoor, Devanand

    2007-07-01

    The efficiency of vetiver grass (Vetiveria zizanioides) in removing 2,4,6-trinitrotoluene (TNT) from aqueous media was explored in the presence of a common agrochemical, urea, used as a chaotropic agent. Chaotropic agents disrupt water structure, increasing solubilization of hydrophobic compounds (TNT), thus, enhancing plant TNT uptake. The primary objectives of this study were to: (i) characterize TNT absorption by vetiver in hydroponic media, and (ii) determine the effect of urea on chemically catalyzing TNT uptake by vetiver grass in hydroponic media. Results showed that vetiver exhibited a high TNT uptake capacity (1.026 mgg(-1)), but kinetics were slow. Uptake was considerably enhanced in the presence of urea, which significantly (p<0.001) increased the 2nd-order reaction rate constant over that of the untreated (no urea) control. Three major TNT metabolites were detected in the roots, but not in the shoot, namely 1,3,5-trinitrobenzene, 4-amino 2,6-dinitrotoluene, and 2-amino 4,6-dinitrotoluene, indicating TNT degradation by vetiver grass.

  18. Conjugated microporous polymers-based fluorescein for fluorescence detection of 2,4,6-trinitrophenol.

    PubMed

    Geng, Tong-Mou; Ye, Sai-Nan; Wang, Yu; Zhu, Hai; Wang, Xie; Liu, Xue

    2017-04-01

    2,4,6-Trinitrophenol (TNP, also called picric acid, PA) pose a large threat to environmental health, public safety and military security. Conjugated microporous polymers are emerging new fluorescence sensing materials for TNP. In this paper, we report the synthesis of two fluorescein containing conjugated microporous polymers (DTF and TTF) through the palladium catalyzed Sonogashira-Hagihara polycondensation reactions of tetraiodofluorescein sodium salt (TIFA) with 1,4-diethynylbenzene (DEB) or 1,3,5-triethynylbenzene (TEB). DTF and TTF are porous with the BET surface areas of 705 and 712m(2)g(-1) and exhibit high chemical and thermal stabilities. The formation of conjugated polymers with the incorporation of ethynyl groups leads to the fluorescent properties. The fluorescence quenching behaviors of DTF by nitroaromatic analytes in THF suspension are investigated. It is found that the fluorescence of DTF can be effectively quenched by 2,4,6-trinitrophenol over 2-nitrophenol (NP), 4-nitrotoluene (NT), nitrobenzene (NB), phenol (PhOH), p-dichlorobenzene (DClB) and 2,4-dinitrotoluene (DNT) with an SV constant of 2.08×10(3)Lmol(-1) and a detection limit of 7.22×10(-7)molL(-1) (0.165mgL(-1)). In short, the DTF may be a new kind of fluorescence sensing material for detecting TNP.

  19. Dosimetric shield evaluation with tungsten sheet in 4, 6, and 9MeV electron beams.

    PubMed

    Fujimoto, Takahiro; Monzen, Hajime; Nakata, Manabu; Okada, Takashi; Yano, Shinsuke; Takakura, Toru; Kuwahara, Junichi; Sasaki, Makoto; Higashimura, Kyoji; Hiraoka, Masahiro

    2014-11-01

    In electron radiotherapy, shielding material is required to attenuate beam and scatter. A newly introduced shielding material, tungsten functional paper (TFP), has been anticipated to become a very useful device that is lead-free, light, flexible, and easily processed, containing very fine tungsten powder at as much as 80% by weight. The purpose of this study was to investigate the dosimetric changes due to TFP shielding for electron beams. TFP (thickness 0-15mm) was placed on water or a water-equivalent phantom. Percentage depth ionization and transmission were measured for 4, 6, and 9MeV electron beams. Off-center ratio was also measured using film dosimetry at depth of dose maximum under similar conditions. Then, beam profiles and transmission with two shielding materials, TFP and lead, were evaluated. Reductions of 95% by using TFP at 0.5cm depth occurred at 4, 9, and 15mm with 4, 6, and 9MeV electron beams, respectively. It is found that the dose tend to increase at the field edge shaped with TFP, which might be influenced by the thickness. TFP has several unique features and is very promising as a useful tool for radiation protection for electron beams, among others.

  20. Growth and characterization of a new nonlinear optical organic crystal: 2,4,6-Trimethylacetanilide

    NASA Astrophysics Data System (ADS)

    Upadhyaya, V.; Prabhu, Sharada G.

    2015-09-01

    A new nonlinear optical organic material, 2,4,6-trimethylacetanilide (246TMAA), also known as N-[2,4,6- trimethylphenyl]acetamide, has been synthesized and grown as a single crystal by the slow evaporation technique by organic solvents. The grown crystals have been characterized by morphology study. The crystals are prismatic. Surface examination shows granular dendritic pattern in optical micrograph. The Scanning Electron Micrograph shows the layered growth of the crystal. The Differential Scanning Calorimeter plot shows no phase change until melting point (219°C). The density of the crystals is 1.1g/cc and the crystals are soft. The crystals are transparent in the visible region and in the ultra-violet region till 280 nm. 246TMAA crystallizes with 2 molecules in a monoclinic unit cell in the noncentrosymmetric point group m, space group Pn. Refractive indices of this optically biaxial crystal along the three crystallophysical axes have been measured at 633 nm. The optical second harmonic generation efficiency of the crystal at 1064 nm is about half that of the urea crystal, measured by powder method using Nd:YAG laser. The results show that the 246TMAA crystal can efficiently be used for up-conversion of infrared radiation into visible green light. The powder X-ray diffraction spectrum of the crystal has been obtained.

  1. Flexible Pedagogies: Part-Time Learners and Learning in Higher Education. Flexible Pedagogies: Preparing for the Future Series

    ERIC Educational Resources Information Center

    McLinden, Michael

    2013-01-01

    This publication focuses on national and international policy initiatives to develop a better understanding of part-time learners and the types of flexibility that may enhance their study especially pedagogically. As part of our five-strand research project "Flexible Pedagogies: preparing for the future" it: (1) highlights the challenges…

  2. Recruitment and Retention of Full-Time Engineering Faculty, Fall 1980. Higher Education Panel Report Number 52.

    ERIC Educational Resources Information Center

    Atelsek, Frank J.; Gomberg, Irene L.

    The extent of faculty vacancies in colleges of engineering, the effects of such vacancies upon research and instructional programs, and the nature of the competition between academia and industry in hiring engineering faculty were surveyed. The focus is on permanent full-time faculty positions in the following major engineering fields:…

  3. Pulling Structured Inequality into Higher Education: The Impact of Part-Time Working on English University Students

    ERIC Educational Resources Information Center

    Humphrey, Robin

    2006-01-01

    This paper explores the social and academic effects of term-time working on undergraduate students at an English university. Data initially collected via a survey of student social relationships were enhanced by the inclusion of end-of-year academic performance. Various inferential statistical techniques were used to identify these effects. Path…

  4. Does a Higher Incidence of Break Times in Primary Schools Result in Children Being More Physically Active?

    ERIC Educational Resources Information Center

    Kobel, Susanne; Kettner, Sarah; Erkelenz, Nanette; Kesztyüs, Dorothea; Steinacker, Jürgen M.

    2015-01-01

    Background: Regular physical activity (PA) has multiple benefits to health; however, the majority of schoolchildren do not reach PA guidelines of 60 minutes of moderate to vigorous PA (MVPA) daily. During the school day, break times are often the only opportunity for children to be physically active. This study investigated PA levels during school…

  5. The Economic Domino Effect: A Phenomenological Study Exploring Community College Faculty's Lived Experiences during Financial Hard Times in Higher Education

    ERIC Educational Resources Information Center

    Taylor, Tridai A.

    2014-01-01

    This qualitative study explored the lived experiences of eight full-time community college faculty members who taught during the economic crisis of 2008. The study was guided by the central research question, "How do community college faculty members describe their lived experiences regarding the recent economic crisis of 2008 and its impact…

  6. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene from 3,5-dichloranisole

    DOEpatents

    Ott, Donald G.; Benziger, Theodore M.

    1990-01-01

    Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) from 3,5-dichloroanisole. Nitration of 3,5-dichloroanisole under relatively mild conditions gave 3,5-dichloro-2,4,6-trinitroanisole in high yield and purity. Ammonolysis of this latter compound gave the desired TATB. Another route to TATB was through the treatment of the 3,5-dichloro-2,4,6-trinitroanisole with thionyl chloride and dimethylformamide to yield 1,3,5-trichloro-2,4,6-trinitrobenzene. Ammonolysis of this product produced TATB.

  7. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene from 3,5-dichloroanisole

    DOEpatents

    Ott, Donald G.; Benziger, Theodore M.

    1991-01-01

    Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) from 3,5-dichloroanisole. Nitration of 3,5-dichloroanisole under relatively mild conditions gave 3,5-dichloro-2,4,6-trinitroanisole in high yield and purity. Ammonolysis of this latter compound gave the desired TATB. Another route to TATB was through the treatment of the 3,5-dichloro-2,4,6-trinitroanisole with thionyl chloride and dimethylformamide to yield 1,3,5-trichloro-2,4,6-trinitrobenzene. Ammonolysis of this product produced TATB.

  8. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene from 3,5-dichloroanisole

    DOEpatents

    Ott, D.G.; Benziger, T.M.

    1991-03-05

    Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) from 3,5-dichloroanisole is described. Nitration of 3,5-dichloroanisole under relatively mild conditions gave 3,5-dichloro-2,4,6-trinitroanisole in high yield and purity. Ammonolysis of this latter compound gave the desired TATB. Another route to TATB was through the treatment of the 3,5-dichloro-2,4,6-trinitroanisole with thionyl chloride and dimethylformamide to yield 1,3,5-trichloro-2,4,6-trinitrobenzene. Ammonolysis of this product produced TATB. 8 figures.

  9. A new approach to measure single-event related brain activity using real-time fMRI: feasibility of sensory, motor, and higher cognitive tasks.

    PubMed

    Posse, S; Binkofski, F; Schneider, F; Gembris, D; Frings, W; Habel, U; Salloum, J B; Mathiak, K; Wiese, S; Kiselev, V; Graf, T; Elghahwagi, B; Grosse-Ruyken, M L; Eickermann, T

    2001-01-01

    Real-time fMRI is a rapidly emerging methodology that enables monitoring changes in brain activity during an ongoing experiment. In this article we demonstrate the feasibility of performing single-event sensory, motor, and higher cognitive tasks in real-time on a clinical whole-body scanner. This approach requires sensitivity optimized fMRI methods: Using statistical parametric mapping we quantified the spatial extent of BOLD contrast signal changes as a function of voxel size and demonstrate that sacrificing spatial resolution and readout bandwidth improves the detection of signal changes in real time. Further increases in BOLD contrast sensitivity were obtained by using real-time multi-echo EPI. Real-time image analysis was performed using our previously described Functional Imaging in REal time (FIRE) software package, which features real-time motion compensation, sliding window correlation analysis, and automatic reference vector optimization. This new fMRI methodology was validated using single-block design paradigms of standard visual, motor, and auditory tasks. Further, we demonstrate the sensitivity of this method for online detection of higher cognitive functions during a language task using single-block design paradigms. Finally, we used single-event fMRI to characterize the variability of the hemodynamic impulse response in primary and supplementary motor cortex in consecutive trials using single movements. Real-time fMRI can improve reliability of clinical and research studies and offers new opportunities for studying higher cognitive functions.

  10. Summary of External Peer Review and Public Comments and Disposition for 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8,-hexamethylcyclopenta[γ]-2-benzopyran (HHCB)

    EPA Pesticide Factsheets

    This document summarizes the public and external peer review comments that the EPA’s Office of Pollution Prevention and Toxics (OPPT) received for the draft work plan risk assessment for 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethylcyclopenta--2-benzopyran

  11. A Versatile Synthesis of 1,3,5-Triamino-2,4,6-Trinitrobenzene (TATB)

    SciTech Connect

    Mitchell, A R; Pagoria, P F; Schmidt, R D; Coburn, M D; Lee, G S; Hsu, P C

    2006-04-06

    A safe and versatile synthesis of high-purity 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) based on vicarious nucleophilic substitution (VNS) chemistry has now been achieved. The starting material can be selected from a variety of inexpensive nitroarenes obtained from commercial suppliers (4-nitroaniline, picric acid) or U.S. stockpiles (ammonium picrate, TNT). The use of picric acid and ammonium picrate (Explosive D) is preferred as both compounds are directly converted to picramide in the presence of ammonium salts (diammonium hydrogen phosphate, ammonium carbamate) in sulfolane at elevated temperature. The picramide resulting from this process is directly converted to TATB using an optimized VNS reaction employing inexpensive hydroxylamine as the nucleophilic aminating reagent. A crucial element in our synthesis is a novel and efficient purification of TATB.

  12. Reduction of 2,4,6-trinitrotoluene by Clostridium acetobutylicum through hydroxylamino-nitrotoluene intermediates

    SciTech Connect

    Hughes, J.B.; Wang, C.Y.; Bhadra, R.; Richardson, A.; Bennett, G.N.; Rudolph, F.B.

    1998-03-01

    Studies were conducted to isolate and identify intermediates of 2,4,6-trinitrotoluene (TNT) transformation by Clostridium acetobutylicum and to quantify their concentrations in active whole cell cultures. Only two intermediates of TNT reduction were detected in cell cultures and were identified as 4-hydroxylamino-2,6-dinitrotoluene and 2,4-dihydroxylamino-6-nitrotoluene. Structures were confirmed with {sup 1}H-NMR, {sup 13}C-NMR, and desorption chemical ionization mass spectroscopy. When cells were suspended in a non-growth saline medium, both hydroxylamine forms accumulated. In media capable of supporting cell growth, the 2,4-dihydroxylamino-6-nitrotoluene accumulated with concentrations of 4-hydroxylamino-2,6-dinitrotoluene remaining near detection limits. Studies using purified 2,4-dihydroxylamino-6-nitrotoluene confirmed that its biotransformation rate in active cultures greatly exceeded abiotic decomposition in aqueous medium.

  13. 2-Amino-4,6-dimethyl­pyridinium chloride dihydrate

    PubMed Central

    Al-Dajani, Mohammad T. M.; Talaat, Jamal; Salhin, Abdusalam; Hemamalini, Madhukar; Fun, Hoong-Kun

    2011-01-01

    In the title hydrated mol­ecular salt, C7H11N2 +·Cl−·2H2O, the pyridine N atom of the 2-amino-4,6-dimethyl­pyridine mol­ecule is protonated. The cation is essentially planar, with a maximum deviation of 0.006 (2) Å. In the crystal, the components are linked by N—H⋯O, N—H⋯Cl and O—H⋯Cl hydrogen bonds, thereby forming sheets lying parallel to (100). The crystal structure is further stabilized by aromatic π–π stacking inter­actions between the pyridinium rings [centroid–centroid distance = 3.4789 (9) Å]. PMID:22058738

  14. Phonological development in 4-6-year-old moderately hearing impaired children.

    PubMed

    Huttunen, K H

    2001-01-01

    The acquisition of clear phonological rules is of utmost importance for a child when he/she is learning to decode and convey meanings using spoken language. Fifteen Finnish-speaking children, five normally hearing (NH) 3-year-olds and 10 moderately hearing impaired (HId) 4-6-year-olds were studied here. Speech samples consisting of 62 words were collected from each child during a picture naming task. Frequent phonetic (articulation) errors together with normal (but delayed) and deviant phonological processes of HId children were found in this study. The frequency and quality of the processes seemed to be related more to the grade of HI than, for example, the age of the child. Implications for speech therapy are briefly discussed.

  15. The 21st LH Gray Conference (June 4-6, 2008)

    SciTech Connect

    C. M. L. West; Martin, C. J.; Sutton, D. G.; Wright, E. G.

    2009-01-12

    The 21st LH Gray Conference, organised by the LH Gray Trust with the Society for Radiological Protection, brought together international experts in radiobiology, epidemiology and risk assessment, and scientists involved in diagnostic and therapeutic radiation exposure. The meeting - held in Edinburgh, Scotland 4-6 June 2008 - aimed to raise awareness, educate and share knowledge of important issues in radiation protection. A distinguished group of speakers discussed topics which included: non-targeted effects of radiation, exposure to high natural background radiation, non-cancer effects in Japanese bomb survivors, lessons learnt from Chernobyl, radiation in the workplace, biokinetic modelling, uncertainties in risk estimation, issues in diagnostic medical exposures, lessons leant from the polonium-210 incidence and how the radiobiology-radiation oncology community is needed to help society prepare for potential future acts of radiation terrorism. The conference highlighted the importance, relevance and topicality of radiobiology today.

  16. High uptake of 2,4,6-trinitrotoluene by vetiver grass--potential for phytoremediation?

    PubMed

    Makris, Konstantinos C; Shakya, Kabindra M; Datta, Rupali; Sarkar, Dibyendu; Pachanoor, Devanand

    2007-03-01

    2,4,6-Trinitrotoluene (TNT) is a potent mutagen, and a Group C human carcinogen that has been widely used to produce munitions and explosives. Vast areas that have been previously used as ranges, munition burning, and open detonation sites are heavily contaminated with TNT. Conventional remediation activities in such sites are expensive and damaging to the ecosystem. Phytoremediation offers a cost-effective, environment-friendly solution, utilizing plants to extract TNT from contaminated soil. We investigated the potential use of vetiver grass (Vetiveria zizanioides) to effectively remove TNT from contaminated solutions. Vetiver grass plants were grown in hydroponic systems containing 40 mg TNTL(-1) for 8d. Aqueous concentrations of TNT reached the method detection limit ( approximately 1 microg L(-1)) within the 8-d period, demonstrating high affinity of vetiver for TNT, without any visible toxic effects. Results from this preliminary hydroponic study are encouraging, but in need of verification using TNT-contaminated soils.

  17. A unique macrolactam derivative via a [4+6]-cycloaddition from Streptomyces niveus.

    PubMed

    Li, Liya; Cai, Yaping; Jiang, Yi; Liu, Jiang; Ma, Jian; Yuan, Chunhui; Mu, Yu; Han, Li; Huang, Xueshi

    2016-03-15

    One new macrolactam derivative, nivelactam (1) and one new polyenoic acid derivative, niveamide (2), along with two other known 20-atom macrolactams (3 and 4) were isolated from the fermentation broth of Streptomyces niveus, which obtained from the forest soil in northeastern China. The structures of 1 and 2 were elucidated on the basis of HRESIMS, IR, and NMR spectroscopic data analyses. Compound 1 was proposed as an intramolecular [4+6]-cycloaddition product of 3 by S. niveus, and displayed moderate cytotoxic activity against a panel of human tumor cell lines in vitro, with IC50 values ranging from 3.76 ± 0.58 to 15.02 ± 2.81 μM.

  18. Adsorption of 2,4,6-trinitrotoluene on carboxylated porous polystyrene microspheres

    NASA Astrophysics Data System (ADS)

    Ye, Zhengfang; Meng, Qingqiang; Lu, Shengtao

    2012-02-01

    Large-pore-size (150 nm) polystyrene (PSt) microspheres were carboxylated with phthalic anhydride (PA) through Friedel-Crafts acetylation to study the adsorption of 2,4,6-trinitrotoluene (TNT) on this material from aqueous solution. The scanning electron microscope (SEM) images and mercury porosimetry measurements (MPM) of the microspheres showed that the pore structure was unchanged during the reaction. High adsorption capacity (11.2 mg g-1 of suction-dried adsorbent) and adsorption rate (33.9 mg g-1 h-1) for TNT were observed during the study. As shown by the adsorption isotherm, the adsorption of TNT on PA-PSt can be described by the Freundlich adsorption equation, indicating heterogeneous adsorption process. On-column adsorption of TNT on PA-PSt and elution indicated that TNT can be completely removed from aqueous solution and condensed into acetone.

  19. Biosynthesis of the 1,3,4,6-hexanetetracarboxylic acid subunit of methanofuran

    SciTech Connect

    White, R.H.

    1987-06-02

    /sup 2/H- and /sup 13/C-labeled precursors were used to establish the pathway for the biosynthesis of the 1,3,4,6-hexanetetracarboxylic acid (TCA) component of methanofuran, which is found in some methanogenic bacteria. The extent and position of incorporation of label into TCA were measured from the mass spectrum of the tetramethyl ester of TCA that was prepared from methanofuran present in cells grown in the presence of labeled acetate. (2,2,2-/sup 2/H/sub 3/)Acetate was found to incorporate deuterium into two separate sites of the TCA molecule, with one on each side of the symmetrical molecule. One site was found to be labeled 37% with deuterium, the same as for the glutamic acid present in the cells; the other site was labeled 77% with deuterium, the same as for the malonate-derived compounds in the cells. An analog of TCA, 1-hydroxy-1,3,4,6-hexanetetracarboxylic acid, found in methanofuran isolated from Methanobrevibacter smithii, was found to incorporate /sup 13/C/sub 2/ units from (1,2-/sup 13/C/sub 2/)acetate into three positions of the molecule. One of the acetate /sup 13/C/sub 2/ units was incorporated into the non-hydroxyl-containing side of the molecule (carbons 4, 5, and 6 and the C-6 carboxylic acid group), and two acetate units were incorporated into the hydroxyl-containing side of the molecule (carbons 1, 2, and 3 and the C-1 carboxylic acid group). On the basis of this and additional information, it is concluded that TCA is biosynthesized by the condensation of ..cap alpha..-ketoglutaric acid with malonic acid to form 1,1,2,4-butanetetracarboxylic acid, which is further condensed with a second molecule of malonate, in a series of reactions analogous to those observed during fatty acid biosynthesis, to form TCA.

  20. Development of a microwave assisted extraction method for the analysis of 2,4,6-trichloroanisole in cork stoppers by SIDA-SBSE-GC-MS.

    PubMed

    Vestner, Jochen; Fritsch, Stefanie; Rauhut, Doris

    2010-02-15

    The aim of this research work was focused on the replacement of the time-consuming soaking of cork stoppers which is mainly used as screening method for cork lots in connection with sensory analysis and/or analytical methods to detect releasable 2,4,6-trichloroanisole (TCA) of natural cork stoppers. Releasable TCA from whole cork stoppers was analysed with the application of a microwave assisted extraction method (MAE) in combination with stir bar sorptive extraction (SBSE). The soaking of corks (SOAK) was used as a reference method to optimise MAE parameters. Cork lots of different quality and TCA contamination levels were used to adapt MAE. Pre-tests indicated that an MAE at 40 degrees C for 120 min with 90 min of cooling time are suitable conditions to avoid an over-extraction of TCA of low and medium tainted cork stoppers in comparison to SOAK. These MAE parameters allow the measuring of almost the same amounts of releasable TCA as with the application of the soaking procedure in the relevant range (<25 ng L(-1) releasable TCA from one cork) to evaluate the TCA level of cork stoppers. Stable isotope dilution assay (SIDA) was applied to optimise quantification of the released TCA with deuterium-labelled TCA (TCA-d(5)) using a time-saving GC-MS technique in single ion monitoring (SIM) mode. The developed MAE method allows the measuring of releasable TCA from the whole cork stopper under improved conditions and in connection with a low use of solvent and a higher sample throughput.

  1. SEDIMENT-MEDIATED REDUCTION OF 2,4,6-TRINITROTOLUENE AND FATE OF THE RESULTING AROMATIC (POLY)AMINES

    EPA Science Inventory

    2,4,6-Trinitrotoluene is a major surface and subsurface contaminant found at numerous munitions production and storage facilities. The reductive transformation of 2,4,6-trinitrotoluene (TNT) to aromatic (poly)amines and the consequent fate of these products were studied in anaer...

  2. Thermal processing of acidified foods with pH 4.1 to pH 4.6

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Shelf-stable acidified foods with a pH at or below 4.6 must be processed to achieve a 5-log reduction for vegetative bacterial pathogens. Published research does not exist to adequately support the Food and Drug Administration process filings for products with pH 4.1–4.6 or to define critical limits...

  3. 17 CFR 4.6 - Exclusion for certain otherwise regulated persons from the definition of the term “commodity...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 17 Commodity and Securities Exchanges 1 2013-04-01 2013-04-01 false Exclusion for certain otherwise regulated persons from the definition of the term âcommodity trading advisor.â 4.6 Section 4.6 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION COMMODITY POOL OPERATORS...

  4. 17 CFR 4.6 - Exclusion for certain otherwise regulated persons from the definition of the term “commodity...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 1 2014-04-01 2014-04-01 false Exclusion for certain otherwise regulated persons from the definition of the term âcommodity trading advisor.â 4.6 Section 4.6 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION COMMODITY POOL OPERATORS AND COMMODITY TRADING ADVISORS General...

  5. 17 CFR 4.6 - Exclusion for certain otherwise regulated persons from the definition of the term “commodity...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 17 Commodity and Securities Exchanges 1 2012-04-01 2012-04-01 false Exclusion for certain otherwise regulated persons from the definition of the term âcommodity trading advisor.â 4.6 Section 4.6 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION COMMODITY POOL OPERATORS AND COMMODITY TRADING ADVISORS General...

  6. Design of a novel Cu₂O/TiO₂/carbon aerogel electrode and its efficient electrosorption-assisted visible light photocatalytic degradation of 2,4,6-trichlorophenol.

    PubMed

    Wang, Yabo; Zhang, Ya-Nan; Zhao, Guohua; Tian, Hongyi; Shi, Huijie; Zhou, Tianchen

    2012-08-01

    Cu(2)O/TiO(2) heterojunction photocatalyst is built on carbon aerogel (CA) substrate with good adsorption properties by sol impregnation and seed-mediated synthesis approach. The Cu(2)O/TiO(2)/CA electrode has excellent electrosorptive and high efficient photocatalytic properties. Its morphology and surface chemical composition are characterized with SEM, TEM, X-ray diffraction (XRD) and Raman spectra. The UV-vis diffuse reflectance spectra show that the optical absorption edge for Cu(2)O/TiO(2)/CA appears at 636 nm. Under visible-light (λ > 420 nm) irradiation, the photocurrent density increment on Cu(2)O/TiO(2)/CA is 60 times of that on Cu(2)O/TiO(2)/FTO. The electrochemical characteristic is investigated with electrochemical impedance spectrum (EIS). The Cu(2)O/TiO(2)/CA electrode is further applied in the electrosorptive photodegradation of the 2,4,6-trichlorophenol (2,4,6-TCP) wastewater. The result shows that the removal ratio of 2,4,6-TCP in 5.5 h on Cu(2)O/TiO(2)/CA is 96.3% and the TOC removal is 91.3%. The intermediates generated in the degradation process are analyzed by GC-MS and HPLC. The possible mechanism of visible light photocatalytic degradation of 2,4,6-TCP on Cu(2)O/TiO(2)/CA is also studied.

  7. Late time acceleration of the 3-space in a higher dimensional steady state universe in dilaton gravity

    SciTech Connect

    Akarsu, Özgür; Dereli, Tekin E-mail: tdereli@ku.edu.tr

    2013-02-01

    We present cosmological solutions for (1+3+n)-dimensional steady state universe in dilaton gravity with an arbitrary dilaton coupling constant w and exponential dilaton self-interaction potentials in the string frame. We focus particularly on the class in which the 3-space expands with a time varying deceleration parameter. We discuss the number of the internal dimensions and the value of the dilaton coupling constant to determine the cases that are consistent with the observed universe and the primordial nucleosynthesis. The 3-space starts with a decelerated expansion rate and evolves into accelerated expansion phase subject to the values of w and n, but ends with a Big Rip in all cases. We discuss the cosmological evolution in further detail for the cases w = 1 and w = ½ that permit exact solutions. We also comment on how the universe would be conceived by an observer in four dimensions who is unaware of the internal dimensions and thinks that the conventional general relativity is valid at cosmological scales.

  8. Building on Strengths in a Time of Retrenchment: Developing an M.Ed. in Higher Education--Student Affairs Emphasis to Train Christian Practitioners

    ERIC Educational Resources Information Center

    Morris, Jason; Haseltine, Jeffrey; Williams, Carol

    2007-01-01

    To gain approval of a new master's degree in difficult financial times, the authors applied strategies that are applicable at other institutions. Using existing internal resources to build on the university's mission was key in developing a new M.Ed. in Higher Education--Student Affairs Emphasis at Abilene Christian University. Creativity and…

  9. Soft-Decision Viterbi Decoding Scheme and a New Reliability Metric for 4/6 Modulation Code in Holographic Data Storage

    NASA Astrophysics Data System (ADS)

    Kim, Yongok; Kong, Gyuyeol; Choi, Sooyong

    2012-08-01

    A soft-decision Viterbi decoding for a 4/6 modulation code is proposed in a holographic data storage system. Since the previous proposed soft-decision Viterbi decoding does not support a higher rate modulation codes than 1/2 rate modulation codes, we propose a new reliability metric to support the 4/6 modulation code. The reliability metric is used to calculate the branch metric on the trellis. For a better coding gain, we find a symbol mapping method for the modulation code which provides a large free distance on the trellis to have the enhanced error correcting capability. Simulation results show that the proposed scheme has about 2 dB coding gains than the conventional soft-decision Viterbi decoding scheme.

  10. Fate of 3-tert-Butyl-4-hydroxyanisole, 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8- hexamethylcyclopenta(g)-2-benzopyrane and chlorpyrifos in a Conventional Wastewater Treatement Plant

    NASA Astrophysics Data System (ADS)

    Thomas, S. M.; Bodour, A.; Inniss, E. C.; Murray, K. E.

    2007-12-01

    Emerging contaminants (ECs) are a major concern in the environment, particularly those found in waters. Wastewater treatment plants (WWTPs) play a key role in reducing the concentrations in the environment because compounds may be transformed under either aerobic or anaerobic conditions or may sorb to wastewater sludges and therefore be removed from waters. If these ECs are not contained or treated then effluent discharged from the WWTP and to a receiving stream may contain hazardous levels of these contaminants. Reported here is a study of the fate of three emerging contaminants (ECs): 3-tert-Butyl-4-hydroxyanisole (BHA), 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta(g)-2-benzopyrane (HHCB) and chlorpyrifos. Experiments were conducted on a laboratory scale by emulating conditions of a conventional WWTP in San Antonio, TX. The goal of the research was to determine general characteristics for both sorption (to wastewater sludges) and degradation. The sorption experiments were performed by exposing the sludge to a variety of initial concentration of ECs for 24 hours. After exposure these three ECs were extracted and analyzed using gas chromatography followed by flame ionization detector (GC/FID). Sorption experiments indicated that HHCB and chlorpyrifos are more hydrophobic than BHA and, therefore, would be mostly contained in the sludges. The degradation rates for these ECs were also considered for both aerobic and anaerobic conditions using different bench-scale reactor setups for 21 days. The differences between the reactor setups included volume of reactor, amount of sludge, mode of supply of nutrients and acclimatization of sludge to the ECs. One sludge was first acclimated to EC concentrations and then used in the experiment. The acclimated reactor had reaction rate constants approximately double that of the non-acclimated sludge reactor setups and followed first order reaction kinetics. Aerobic degradation occurred more readily for all three compounds

  11. Spectrophotometric determination of 4,6-dinitro-o-cresol (DNOC) in soil and lemon juice.

    PubMed

    Uzer, A; Ercag, E; Parlar, H; Apak, R; Filik, H

    2006-10-27

    Although the use of once widely applied selective herbicide, 4,6-dinitro-o-cresol (DNOC), was cancelled by US-EPA in 1987, it is still found in soil and water due to its slow degradation in the environment. Since solid phase extraction-spectrophotometry combinations are much simpler and cheaper than chromatography/MS based methods and most routine laboratories lack such sophisticated instrumentation, it is desirable to establish novel sensitive, well-established, and field-applicable spectrophotometric methods for the rapid assay of DNOC in water and soil. For this purpose, two distinct spectrophotometric methods utilizing the periodate and copper(II)-neocuproine (Nc) reagents have been developed following Zn/HCl reduction of the pesticide in a microwave oven for 15s, and validated for DNOC determination at mg L(-1) level. The LOD values were 1.6 and 0.2 mg L(-1) for periodate and Cu(II)-Nc methods, respectively. Statistical comparison of the developed methods was made with the aid of high performance liquid chromatography (HPLC) equipped with a C18 (5 microm), 250 mm x 4.6 mm ID reversed phase column in conjunction with a UV (264 nm) detector, and a methanol (HPLC grade) +0.1% glacial acetic acid mixture mobile phase. Both spectrophotometric methods were directly applicable to soil since they were not interfered with common soil cations and anions, together with some pesticides. These methods were applied to real samples such as synthetically contaminated montmorillonite and lemon juice, and overall recovery efficiencies at the order of 95% or greater were achieved in the devised adsorption/elution procedures. An 8-hydroxyquinoline (oxine)-impregnated XAD copolymer resin stabilized with Fe(III) salt was used to preconcentrate DNOC at a concentration factor of 20 from lemon juice contaminated with 1 mg L(-1) DNOC, and the analyte retained at pH 2.5 was eluted with 0.025 M methanolic NaOH. Both the devised spectrophotometric methods and the proposed preconcentration

  12. Using a time-domain higher-order boundary element method to simulate wave and current diffraction from a 3-D body

    NASA Astrophysics Data System (ADS)

    Liu, Zhen; Teng, Bin; Ning, De-Zhi; Sun, Liang

    2010-06-01

    To study wave-current actions on 3-D bodies a time-domain numerical model was established using a higher-order boundary element method (HOBEM). By assuming small flow velocities, the velocity potential could be expressed for linear and higher order components by perturbation expansion. A 4th-order Runge-Kutta method was applied for time marching. An artificial damping layer was adopted at the outer zone of the free surface mesh to dissipate scattering waves. Validation of the numerical method was carried out on run-up, wave exciting forces, and mean drift forces for wave-currents acting on a bottom-mounted vertical cylinder. The results were in close agreement with the results of a frequency-domain method and a published time-domain method. The model was then applied to compute wave-current forces and run-up on a Seastar mini tension-leg platform.

  13. Pichia pastoris secretes recombinant proteins less efficiently than Chinese hamster ovary cells but allows higher space-time yields for less complex proteins.

    PubMed

    Maccani, Andreas; Landes, Nils; Stadlmayr, Gerhard; Maresch, Daniel; Leitner, Christian; Maurer, Michael; Gasser, Brigitte; Ernst, Wolfgang; Kunert, Renate; Mattanovich, Diethard

    2014-04-01

    Chinese hamster ovary (CHO) cells are currently the workhorse of the biopharmaceutical industry. However, yeasts such as Pichia pastoris are about to enter this field. To compare their capability for recombinant protein secretion, P. pastoris strains and CHO cell lines producing human serum albumin (HSA) and the 3D6 single chain Fv-Fc anti-HIV-1 antibody (3D6scFv-Fc) were cultivated in comparable fed batch processes. In P. pastoris, the mean biomass-specific secretion rate (qp ) was 40-fold lower for 3D6scFv-Fc compared to HSA. On the contrary, qp was similar for both proteins in CHO cells. When comparing both organisms, the mean qp of the CHO cell lines was 1011-fold higher for 3D6scFv-Fc and 26-fold higher for HSA. Due to the low qp of the 3D6scFv-Fc producing strain, the space-time yield (STY) was 9.6-fold lower for P. pastoris. In contrast, the STY of the HSA producer was 9.2-fold higher compared to CHO cells because of the shorter process time and higher biomass density. The results indicate that the protein secretion machinery of P. pastoris is much less efficient and the secretion rate strongly depends on the complexity of the recombinant protein. However, process efficiency of the yeast system allows higher STYs for less complex proteins.

  14. Expression of an (Engineered) 4,6-α-Glucanotransferase in Potato Results in Changes in Starch Characteristics

    PubMed Central

    Xu, Xuan; Dechesne, Annemarie; Visser, Richard G. F.; Trindade, Luisa M.

    2016-01-01

    Starch structure strongly influences starch physicochemical properties, determining the end uses of starch in various applications. To produce starches with novel structure and exploit the mechanism of starch granule formation, an (engineered) 4, 6-α-glucanotransferase (GTFB) from Lactobacillus reuteri 121 was introduced into two potato genetic backgrounds: amylose-containing line Kardal and amylose-free mutant amf. The resulting starches showed severe changes in granule morphology regardless of genetic backgrounds. Modified starches from amf background exhibited a significant increase in granule size and starch phosphate content relative to the control, while starches from Kardal background displayed a higher digestibility, but did not show changes in granule size and phosphate content. Transcriptome analysis revealed the existence of a mechanism to restore the regular packing of double helices in starch granules, which possibly resulted in the removal of novel glucose chains potentially introduced by the (engineered) GTFB. This amendment mechanics would also explain the difficulties to detect alterations in starch fine structure in the transgenic lines. PMID:27911907

  15. Hydrogen bonding and molecular rearrangement in 1,3,5-triamino-2,4,6-trinitrobenzene under compression.

    PubMed

    Ojeda, Oscar U; Çağın, Tahir

    2011-10-27

    We studied the structural behavior and properties of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) under hydrostatic compression using atomistic and electronic (ab initio) level computations. We observed a marked change in the intermolecular hydrogen-bonding network upon compression of the crystal without change in crystal symmetry. The changes in molecular arrangement are found to have a profound impact on various observable properties: energetic, vibrational spectra, structural, and elastic properties. From the analysis of vibrational modes, we observed that the changes are mainly due to the nitro and amino groups. An increase in the number of hydrogen bonding interactions along the c-axis of the crystals results in providing the extra stabilization energy. In addition to analyze the isolated molecule and dimer, this molecular rearrangement is systematically studied and characterized in the condensed phase. From higher-level ab initio calculations, the potential energy surface of the dimer indicates the presence of a region with two local minima within 3.42 kcal/mol difference in energy. Since this behavior is not associated with a change of symmetry of the crystal unit cell, the possible coexistence of two molecular arrangements might lead to the loss of a definitive inversion center for bulk. The calculated elastic constants of the crystal dramatically reveal the changes via large increases in certain components. Implications on the observed pressure-induced rearrangement behavior on the mechanical, optical, and thermodynamic properties of TATB are further discussed, and correlations with experimental spectroscopic data are provided.

  16. The role of nutrients in the biodegradation of 2,4,6-trinitrotoluene in liquid and soil.

    PubMed

    Muter, Olga; Potapova, Katrina; Limane, Baiba; Sproge, Kristine; Jakobsone, Ida; Cepurnieks, Guntis; Bartkevics, Vadims

    2012-05-15

    The widely used explosive 2,4,6-trinitrotoluene (TNT) has residues that are potentially explosive, toxic, and mutagenic. TNT and other explosives can be degraded by microorganisms; however, biostimulation is needed for process efficiency. To investigate the effectiveness of using biostimulation to degrade TNT, we added varying concentrations of a nutrient amendment consisting of inorganic salts, plant extracts, and molasses to soil and liquid media. For the inoculum we used a consortium of bacteria AM 06 that had exhibited the ability to degrade TNT and which had been previously isolated from explosives-contaminated soils. Phylogenetically, the clones clustered into seven different genera: Klebsiella, Raoultella, Serratia, Stenotrophomonas, Pseudoxanthomonas, Achromobacter and Pseudomonas. The addition of AM 06 consortium to a liquid environment along with 100% nutrient amendment decreased the amount of TNT (and its degradation products) by up to 90% after 14 days incubation. At the total amount of TNT was less than 100 mg/l, the concentration of TNT did not influence the amount of sugar consumed by the bacteria consortium. In soil media, the TNT degradation process was dependent on the concentration of nutrient amendment added. At higher initial concentrations of TNT (500 mg/kg), bioaugmentation (i.e., addition of bacteria inoculum) had a demonstrated effect, especially when nutrient concentrations of 50% and 100% were added to the soil. Findings of this study could further the understanding of the TNT biodegradation processes in water and soil and provide for optimization of the technological conditions for bioremediation.

  17. Sensitivity of KRAS-Mutant Colorectal Cancers to Combination Therapy that Co-Targets MEK and CDK4/6

    PubMed Central

    Ziemke, Elizabeth K.; Dosch, Joseph S.; Maust, Joel D.; Shettigar, Amrith; Sen, Ananda; Welling, Theodore H.; Hardiman, Karin M.; Sebolt-Leopold, Judith S.

    2015-01-01

    Purpose The emerging need for rational combination treatment approaches led us to test the concept that co-targeting MEK and CDK4/6 would prove efficacious in KRAS mutant (KRASmt) colorectal cancers, where upregulated CDK4 and hyperphosphorylated retinoblastoma (RB) typify the vast majority of tumors. Experimental Design Initial testing was carried out in the HCT-116 tumor model, which is known to harbor a KRAS mutation. Efficacy studies were then performed with five RB+ patient-derived colorectal xenograft models, genomically diverse with respect to KRAS, BRAF, and PIK3CA mutational status. Tolerance, efficacy, and pharmacodynamic evaluation of target modulation were evaluated in response to daily dosing with either agent alone or concurrent co-administration. Results Synergy was observed in vitro when HCT-116 cells were treated over a broad range of doses of trametinib and palbociclib. Subsequent in vivo evaluation of this model showed a higher degree of antitumor activity resulting from the combination compared to that achievable with single agent treatment. Testing of colorectal patient-derived xenograft (PDX) models further showed that combination of trametinib and palbociclib was well tolerated and resulted in objective responses in all KRASmt models tested. Stasis was observed in a KRAS/BRAF wild type and a BRAFmt model. Conclusions Combination of trametinib and palbociclib was well tolerated and highly efficacious in all three KRAS mutant CRC PDX models tested. Promising preclinical activity seen here supports clinical evaluation of this treatment approach to improve therapeutic outcome for metastatic colorectal cancer patients. PMID:26369631

  18. Initial reductive reactions in aerobic microbial metabolism of 2,4,6-trinitrotoluene.

    PubMed

    Vorbeck, C; Lenke, H; Fischer, P; Spain, J C; Knackmuss, H J

    1998-01-01

    Because of its high electron deficiency, initial microbial transformations of 2,4,6-trinitrotoluene (TNT) are characterized by reductive rather than oxidation reactions. The reduction of the nitro groups seems to be the dominating mechanism, whereas hydrogenation of the aromatic ring, as described for picric acid, appears to be of minor importance. Thus, two bacterial strains enriched with TNT as a sole source of nitrogen under aerobic conditions, a gram-negative strain called TNT-8 and a gram-positive strain called TNT-32, carried out nitro-group reduction. In contrast, both a picric acid-utilizing Rhodococcus erythropolis strain, HL PM-1, and a 4-nitrotoluene-utilizing Mycobacterium sp. strain, HL 4-NT-1, possessed reductive enzyme systems, which catalyze ring hydrogenation, i.e., the addition of a hydride ion to the aromatic ring of TNT. The hydride-Meisenheimer complex thus formed (H-TNT) was further converted to a yellow metabolite, which by electrospray mass and nuclear magnetic resonance spectral analyses was established as the protonated dihydride-Meisenheimer complex of TNT (2H-TNT). Formation of hydride complexes could not be identified with the TNT-enriched strains TNT-8 and TNT-32, or with Pseudomonas sp. clone A (2NT), for which such a mechanism has been proposed. Correspondingly, reductive denitration of TNT did not occur.

  19. 2,4,6-trichlorophenol (TCP) photobiodegradation and its effect on community structure.

    PubMed

    Zhang, Yongming; Pu, Xuejing; Fang, Miaomiao; Zhu, Jun; Chen, Lujun; Rittmann, Bruce E

    2012-07-01

    The mechanisms occurring in a photolytic circulating-bed biofilm reactor (PCBBR) treating 2,4,6-trichlorophenol (TCP) were investigated using batch experiments following three protocols: photodegradation alone (P), biodegradation alone (B), and intimately coupled photodegradation and biodegradation (P&B). Initially, the ceramic particles used as biofilm carriers rapidly adsorbed TCP, particularly in the B experiments. During the first 10 min, the TCP removal rate for P&B was equal to the sum of the rates for P and B, and P&B continued to have the greatest TCP removal, with the TCP concentration approaching zero only in the P&B experiments. When phenol, an easily biodegradable compound, was added along with TCP in order to promote TCP mineralization by means of secondary utilization, P&B was superior to P and B in terms of mineralization of TCP, giving 95% removal of chemical oxygen demand (COD). The microbial communities, examined by clone libraries, changed dramatically during the P&B experiments. Whereas Burkholderia xenovorans, a known degrader of chlorinated aromatics, was the dominant strain in the TCP-acclimated inoculum, it was replaced in the P&B biofilm by strains noted for biofilm formation and biodegrading non-chlorinated aromatics.

  20. Initial Reductive Reactions in Aerobic Microbial Metabolism of 2,4,6-Trinitrotoluene

    PubMed Central

    Vorbeck, Claudia; Lenke, Hiltrud; Fischer, Peter; Spain, Jim C.; Knackmuss, Hans-Joachim

    1998-01-01

    Because of its high electron deficiency, initial microbial transformations of 2,4,6-trinitrotoluene (TNT) are characterized by reductive rather than oxidation reactions. The reduction of the nitro groups seems to be the dominating mechanism, whereas hydrogenation of the aromatic ring, as described for picric acid, appears to be of minor importance. Thus, two bacterial strains enriched with TNT as a sole source of nitrogen under aerobic conditions, a gram-negative strain called TNT-8 and a gram-positive strain called TNT-32, carried out nitro-group reduction. In contrast, both a picric acid-utilizing Rhodococcus erythropolis strain, HL PM-1, and a 4-nitrotoluene-utilizing Mycobacterium sp. strain, HL 4-NT-1, possessed reductive enzyme systems, which catalyze ring hydrogenation, i.e., the addition of a hydride ion to the aromatic ring of TNT. The hydride-Meisenheimer complex thus formed (H−-TNT) was further converted to a yellow metabolite, which by electrospray mass and nuclear magnetic resonance spectral analyses was established as the protonated dihydride-Meisenheimer complex of TNT (2H−-TNT). Formation of hydride complexes could not be identified with the TNT-enriched strains TNT-8 and TNT-32, or with Pseudomonas sp. clone A (2NT−), for which such a mechanism has been proposed. Correspondingly, reductive denitration of TNT did not occur. PMID:16349484

  1. Construction of a Pseudomonas hybrid strain that mineralizes 2,4,6-trinitrotoluene.

    PubMed Central

    Duque, E; Haidour, A; Godoy, F; Ramos, J L

    1993-01-01

    A bacterium, Pseudomonas sp. strain C1S1, able to grow on 2,4,6-trinitrotoluene (TNT), 2,4- and 2,6-dinitrotoluene, and 2-nitrotoluene as N sources, was isolated. The bacterium grew at 30 degrees C with fructose as a C source and accumulated nitrite. Through batch culture enrichment, we isolated a derivative strain, called Pseudomonas sp. clone A, which grew faster on TNT and did not accumulate nitrite in the culture medium. Use of TNT by these two strains as an N source involved the successive removal of nitro groups to yield 2,4- and 2,6-dinitrotoluene, 2-nitrotoluene, and toluene. Transfer of the Pseudomonas putida TOL plasmid pWW0-Km to Pseudomonas sp. clone A allowed the transconjugant bacteria to grow on TNT as the sole C and N source. All bacteria in this study, in addition to removing nitro groups from TNT, reduced nitro groups on the aromatic ring via hydroxylamine to amino derivatives. Azoxy dimers probably resulting from the condensation of partially reduced TNT derivatives were also found. PMID:8468288

  2. Transformation of 2,4,6-trinitrotoluene by the aquatic plant Myriophyllum spicatum

    SciTech Connect

    Pavlostathis, S.G.; Comstock, K.K.; Jacobson, M.E.; Saunders, F.M.

    1998-11-01

    The ability of the aquatic plant Eurasian Watermilfoil (Myriophyllum spicatum) to transform 2,4,6-trinitrotoluene (TNT) was investigated in a series of batch assays. The TNT was added to plant cultures in single and multiple consecutive additions, at various initial concentrations, to determine its transformation kinetics, identify products formed, evaluate phytotoxic effects, and to determine the effect of light deprivation on the TNT transformation process. Rapid disappearance of TNT from the plant culture media was observed. The TNT disappearance rate was a function of both plant and TNT concentration (i.e., followed mixed, second-order kinetics). The TNT transformation occurred only in the presence of plants and was inhibited by the addition of sodium azide. Phytotoxicity leading to plant chlorosis was observed in batch plant cultures with an initial TNT concentration above 5.9 {micro}M. Reductive transformation of TNT to aminodinitrotoluenes and lower levels of hydroxylaminodinitrotoluene and diaminonitrotoluenes detected in the plant culture media accounted for less than 10 to 20% of the total TNT mass added. Extraction of plant material at the end of batch incubations when all TNT was depleted from the media yielded low levels of TNT and aminodinitrotoluenes and accounted for only 3.4% of the initially added TNT mass. Light deprivation decreased both the rate and extent of the reductive transformation of TNT.

  3. Treatment of 2,4,6-trinitrotoluene (TNT) red water by vacuum distillation.

    PubMed

    Zhao, Quanlin; Ye, Zhengfang; Zhang, Mohe

    2010-08-01

    2,4,6-Trinitrotoluene (TNT) red water from Chinese explosive industry was treated by vacuum distillation. The water quality before and after distillation was evaluated using high performance liquid chromatograph, UV-vis spectroscopy, Gas Chromatography/Mass Spectroscopy (GC/MS) and other physical and chemical analyses. The acute toxicity of TNT red water and its distillate was evaluated by determining the luminescence inhibition of Vibrio qinghaiensis sp. Nov. The results showed that the parameters except pH of the distillate met the criterion specified by the Chinese discharge standard for water pollutants from ordnance industry. Distillation removed chemical oxygen demand almost completely and the chrominance was reduced from 100,000 degrees to 17 degrees . The concentrations of 2,4-dinitrotoluene-3-sulfonate and 2,4-dinitrotoluene-5-sulfonate decreased from 20 x 10(3) and 31 x 10(3)mg L(-1) to 1.3 and 1.8 mg L(-1), respectively. GC/MS results showed that most of the organic components of TNT red water can be removed by distillation. The acute toxicity of water sample after distillation reduced 96%, compared with that of unprocessed TNT red water.

  4. Prevalence of Sleep Disorders Among Children 4 - 6 Years Old in Tehran Province, Iran

    PubMed Central

    Ozgoli, Giti; Sheikhan, Zohre; Soleimani, Farin; Nasiri, Malihe; Amiri, Saba

    2016-01-01

    Background Sleep patterns may change over a person’s lifetime; however, the quantity and quality of sleep always depend on individual factors such as age, sex, and psychological and environmental factors. In children, sleep is as important as development. Quantitative sleep problems related to sleep onset and qualitative sleep disorders such as frequent awakenings may lead to insufficient sleep. Objectives This study aimed to assess the prevalence of sleep disorders among children 4 - 6 years old attending the health centers of Shahid Beheshti University of Medical Sciences, Tehran, Iran, in 2013. Patients and Methods This was a cross-sectional study on 400 children selected using a multistage sampling method. Data were collected by interviews. The questionnaire included two sections: a demographic section with questions about the demographic characteristics of the children and parents and a children’s sleep habit questionnaire (CSHQ). Data were analyzed by SPSS 16 and different statistical tests were used (P < 0.05). Results The mean age of the children was 64.27 ± 9.3 months. The prevalence of sleep disorders was 36.25%. Sleep disorders were significantly associated with age, height, body mass index, residence of children, father’s occupation, mother’s diseases, father’s drug abuse, and parents’ marital status (P < 0.05). Conclusions Sleep disorders in children threaten growth and development, and are dangerous for their health. Sleep disorders should be considered in the differential diagnosis of children’s learning and behavioral problems. PMID:27651942

  5. SAGE Analysis of Transcriptome Responses in Arabidopsis Roots Exposed to 2,4,6-Trinitrotoluene1

    PubMed Central

    Ekman, Drew R.; Lorenz, W. Walter; Przybyla, Alan E.; Wolfe, N. Lee; Dean, Jeffrey F.D.

    2003-01-01

    Serial analysis of gene expression was used to profile transcript levels in Arabidopsis roots and assess their responses to 2,4,6-trinitrotoluene (TNT) exposure. SAGE libraries representing control and TNT-exposed seedling root transcripts were constructed, and each was sequenced to a depth of roughly 32,000 tags. More than 19,000 unique tags were identified overall. The second most highly induced tag (27-fold increase) represented a glutathione S-transferase. Cytochrome P450 enzymes, as well as an ABC transporter and a probable nitroreductase, were highly induced by TNT exposure. Analyses also revealed an oxidative stress response upon TNT exposure. Although some increases were anticipated in light of current models for xenobiotic metabolism in plants, evidence for unsuspected conjugation pathways was also noted. Identifying transcriptome-level responses to TNT exposure will better define the metabolic pathways plants use to detoxify this xenobiotic compound, which should help improve phytoremediation strategies directed at TNT and other nitroaromatic compounds. PMID:14551330

  6. Structural diversity in binuclear complexes of alkaline earth metal ions with 4,6-diacetylresorcinol

    NASA Astrophysics Data System (ADS)

    Shebl, Magdy; Khalil, Saied M. E.; Taha, A.; Mahdi, M. A. N.

    2012-11-01

    A new series of binuclear and mixed-ligand complexes with the general formula: [M 2(LO)yClz]; where M = Mg(II), Ca(II), Sr(II) and Ba(II); H2L = 4,6-diacetylresorcinol, the secondary ligand L' = acetylacetone (acac), 8-hydroxyquinoline (8-HQ) or 2,2'-bipyridyl (Bipy), n = 0-2, m = 1, 2, x = 0, 1, 2, 4, y = 0, 2, 4, 5 and z = 0-2; have been synthesized. They have been characterized by the analytical and spectral methods (IR, 1H NMR and mass) as well as TGA and molar conductivity measurements. The spectroscopic and conductance data suggested that the H2L ligand behaves as a neutral, monobasic or dibasic tetradentate ligand, depending on the basicity of the secondary ligand, through the two phenolic and two carbonyl groups. Binuclear octahedral geometry has been assigned to all of the prepared complexes in various molar ratios 2:2; 2:2:2; 1:2:1 and 1:2:4 (L:M:L'). Molecular orbital calculations were performed for the ligands and their complexes using Hyperchem 7.52 program on the bases of PM3 level and the results were correlated with the experimental data. The ligand and some of its alkaline metal(II) complexes showed antibacterial activity towards some of Gram-positive and Gram-negative bacteria, yeast (Candida albicans) and fungus (Aspergillus fumigatus).

  7. 2,4,6-trinitrotoluene transformation by a tropical marine yeast, Yarrowia lipolytica NCIM 3589.

    PubMed

    Jain, M R; Zinjarde, S S; Deobagkar, D D; Deobagkar, D N

    2004-11-01

    Yarrowia lipolytica NCIM 3589, a tropical marine degrader of hydrocarbons and triglycerides transformed 2,4,6-trinitrotoluene (TNT) very efficiently. Though this yeast could not utilize TNT as the sole carbon or nitrogen source, it was capable of reducing the nitro groups in TNT to aminodinitrotoluene (ADNT). In a complete medium containing glucose and ammonium sulphate as the available carbon and nitrogen sources respectively, the culture was able to completely transform 1 mM (227 ppm) of TNT under such conditions. A dual pathway was found to be functional, one of which resulted in the formation of the hydride-Meisenheimer complex (H(-)TNT) as a transiently accumulating metabolite that was subsequently denitrated to 2,4-dinitrotoluene (2,4-DNT), whereas the other pathway resulted in the formation of amino derivatives. The presence of increasing amounts of reducing equivalents in the form of glucose promoted better growth and the nitroreductases of this yeast to reduce the aromatic ring to 2,4-DNT although, the reduction of the nitro groups to amino groups was the major functional pathway. The ability of this tropical marine yeast to transform TNT into products such as 2,4-DNT which in turn could be metabolized by other microbes has implications in the use of this yeast for bioremediation of TNT polluted marine environments.

  8. Germination and seedling development of switchgrass and smooth bromegrass exposed to 2,4,6-trinitrotoluene.

    PubMed

    Peterson, M M; Horst, G L; Shea, P J; Comfort, S D

    1998-01-01

    It is estimated that explosives contaminate approximately 0.82 million cubic metres of soil at former military installations throughout the US; major contaminants often include 2,4,6-trinitrotoluene (TNT) and its degradation products. At some sites, phytoremediation may be a viable option to incineration or other costly remediation treatments. Grasses may be particularly suited for remediation because of their growth habit and adaptability to a wide range of soil and climate conditions. We characterized the effects of TNT on germination and early seedling development of switchgrass and smooth bromegrass to evaluate their potential use on contaminated sites. Switchgrass and smooth bromegrass seeds were germinated in nutrient-free agar containing 0 to 60 mg TNT litre(-1). Smooth bromegrass germination decreased as TNT concentration increased, while switchgrass germination was unaffected by TNT. Concentrations up to 15 mg TNT litre(-1) did not affect switchgrass root growth rate, but bromegrass root growth was reduced at TNT concentrations above 7.5 mg litre(-1). At 7.5 mg TNT litre(-1), however, shoot growth rate was reduced in both species. Examination at 20-fold magnification revealed switchgrass radicles were unaffected by TNT, while smooth bromegrass radicles appeared slightly swollen. Results indicate switchgrass is more tolerant of TNT than smooth bromegrass, but the establishment of both species may be limited to soil containing less than 50 mg kg(-1) of extractable TNT.

  9. Studies in iridoid synthesis. Chemoselective transformations of cis-1,2,4,6-tetrahydrophthalic anhydride.

    PubMed

    Stevens, Anne T; Bull, James R; Chibale, Kelly

    2008-02-07

    In the course of synthetic studies towards the development of diastereoselective routes to secoiridoid aglycones, cis-1,2,4,6-tetrahydrophthalic anhydride was transformed into the corresponding lactone cis-3a,4,7,7a-tetrahydro-3H-isobenzofuran-1-one, which served as a key precursor for a variety of chemoselective synthetic manipulations. Unsuccessful formylation of an ester intermediate resulted in a (E/Z) mixture of vinyl alcohols which were protected as acetates and as a single p-methoxybenzyl (PMB) ether (E) isomer. Dihydroxylation of the cyclohexene motif using OsO(4) led to the unexpected deprotection of the PMB ether. On the other hand, successful formylation of a suitably silyl protected lactonised intermediate was achieved using tert-butoxybis(dimethylamino)methane, or Bredereck's reagent. Tetrabutylammonium fluoride (TBAF) deprotection of a methoxyethoxymethyl (MEM)-ether intermediate serendipitously afforded an approximately 1 : 1 mixture of pyrano-pyranones, which are products of a seldom encountered intramolecular Michael addition, using an oxygen donor, to the terminus of an alpha,beta-unsaturated system, followed by beta-elimination of the MEM moiety.

  10. Sonochemical synthesis of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB)

    SciTech Connect

    Lee, Kien-Yin

    1996-05-01

    The synthesis of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) from trichlorotrinitrobenzene (TCTNB) in toluene and ammonium hydroxide solution under the influence of ultrasonic waves was investigated. When the two-phase reaction mixture was irradiated with high intensity ultrasound at ambient temperature, fine-particle TATB (FP-TATB) was produced. This sonochemically produced TATB powder is lemon color in appearance and was analyzed to have the same explosive properties as reported in the literature. That is, it is insensitive to impact stimuli, and thermally stable. The median particle diameter of FP-TATB was calculated to be around 14 {mu}m, and the powder can be pressed to a density of 1.82 g/cm{sup 3} without a binder. The amination process is simple and requires neither the monitoring of the ammonia gas pressure nor the controlling of the reaction temperature during amination reaction, and we anticipate no problem in large scale production of FP-TATB.

  11. Biodegradation of 2,4,6-trichlorophenol and associated hydraulic conductivity reduction in sand-bed columns.

    PubMed

    Antizar-Ladislao, Blanca; Galil, Noah I

    2006-06-01

    The aim of this research was to investigate the long-term hydraulic conductivity changes in sand-bed columns exposed to 2,4,6-trichlorophenol (TCP). Continuous flow laboratory studies were conducted using sand-bed columns (15 cm i.d.; 200 cm length) at 20+/-1 degrees C during 365 d. The influence of (i) initial loads of 2,4,6-TCP (15, 30, 45 and 60 mg kg(-1) of 2,4,6-TCP), and (ii) recirculating water velocity (0.09, 0.56 and 1.18 cm min(-1)) on the biodegradation of 2,4,6-TCP and hydraulic conductivity changes in the sand-bed columns were investigated. The experimental results indicated that biodegradation of 2,4,6-TCP followed pseudo-first-order kinetics in the range of k(1)=0.01-1.64 d(-1), and it was influenced by initial load (p<0.01) and recirculating water velocity (p<0.01). Indigenous microbial biomass growth and changes resulted in a spatial (180 cm) and temporal (365 d) reduction of hydraulic conductivity in the sand-bed columns by up to two orders of magnitude during biodegradation of 2,4,6-TCP. The fastest hydraulic conductivity reductions were observed in the sand-bed column operated at the highest recirculating water velocity and highest cumulative load of 2,4,6-TCP following 365 d of continuous treatment (p<0.05).

  12. A previously unexposed forest soil microbial community degrades high levels of the pollutant 2,4,6-trichlorophenol.

    PubMed

    Sánchez, M A; Vásquez, M; González, B

    2004-12-01

    2,4,6-trichlorophenol (2,4,6-TCP) is a hazardous pollutant that is efficiently degraded by some aerobic soil bacterial isolates under laboratory conditions. The degradation of this pollutant in soils and its effect on the soil microbial community are poorly understood. We report here the ability of a previously unexposed forest soil microbiota to degrade high levels of 2,4,6-TCP and describe the changes in the soil microbial community found by terminal restriction fragment length polymorphism (T-RFLP) analysis. After 30 days of incubation, about 50% degradation of this pollutant was observed in soils amended with 50 to 5,000 ppm of 2,4,6-TCP. The T-RFLP analysis showed that the soil bacterial community was essentially unchanged after exposure to up to 500 ppm of 2,4,6-TCP. However, a significant decrease in richness was found with 2,000 and 5,000 ppm of 2,4,6-TCP, even though the removal of this pollutant remained high. The introduction of Ralstonia eutropha JMP134 or R. eutropha MS1, two efficient 2,4,6-TCP degraders, to this soil did not improve degradation of this pollutant, supporting the significant bioremediation potential of this previously unexposed, endogenous forest soil microbial community.

  13. Degradation of 2,4,6-trichlorophenol by bacteria isolated from secondary sludge of a pulp and paper mill.

    PubMed

    Karn, Santosh Kr; Reddy, M Sudhakara

    2012-01-01

    Bacterial strains capable of degrading trichlorophenol (2,4,6-TCP) were isolated from the secondary sludge of a pulp and paper mill and were characterized. These isolates were identified as Planococcus rifietoensis (CL4) and Bacillus pumilus (CL5), based on their 16S rRNA sequence analysis. These isolates were able to grow and utilize 2,4,6-TCP as their source of carbon as well as energy. HPLC analysis and stoichometric release of chloride in the medium confirmed the degradation ability of these isolates. Removal efficiency of 2,4,6-TCP by these isolates was discovered to be high. They were able to remove 90% of 2,4,6-TCP when grown at a concentration of 600 mg L(-1). Inoculation of these bacteria completely removed 2,4,6-TCP within 2 weeks from the sludge of the pulp and paper mill when supplemented at the rate of 100 mg L(-1). Absorbable Organic Halogen (AOX) and Extractable Organic Halogen (EOX) were significantly reduced by 63% and 70% respectively from the sludge due to inoculation of these bacteria. These isolates have high potential to remove 2,4,6-TCP and may be used for removal of 2,4,6-TCP from pulp paper mill waste.

  14. Decomposition of some polynitro arenes initiated by heat and shock Part I. 2,4,6-Trinitrotoluene.

    PubMed

    Varga, Róbert; Zeman, Svatopluk

    2006-05-20

    Samples of 2,4,6-trinitrotoluene (TNT) exposed to heat or to shock and residues after their detonation have been analyzed chromatographically (LC-UV and LC/MS). It was found that the main identified decomposition intermediates are identical in all the three cases. 4,6-Dinitro-2,1-benzoisoxazole and 2,4,6-trinitrobenzaldehyde are the most reactive from them. It has been stated that the chemical micro-mechanism of the primary fragmentations of shock-exposed TNT molecules and/or its detonation transformation should be the same as in the case of its low-temperature thermal decomposition.

  15. On the variation of magnetic susceptibility of a molecular crystal with temperature: The 2,4,6-triphenylverdazyl system

    NASA Astrophysics Data System (ADS)

    Datta, Sambhu N.; Navada, Geetha K.

    2004-02-01

    Magnetic susceptibilities of spin-1/2 systems of orthorhombic and higher crystal symmetries have been numerically investigated while taking possible anisotropy in the coupling constants along different crystal axes into account. The work relies on the magnon-based theory of ferromagnetic (FM) and antiferromagnetic (AFM) crystal systems of types FFF, AFF, AAF, and AAA [J. Chem. Phys. 111, 9009 (1999)]. The AAF crystal, in particular, shows interesting changes in the temperature dependence of magnetic susceptibility when the ferromagnetic exchange coupling constant is varied. We especially show that the susceptibility anomalies of molecular crystals fit naturally within the framework of the extended magnon-theoretical formalism, and do not necessarily imply a FM→AFM or a reverse phase transition. A real system, molecular crystal of 2,4,6-triphenylverdazyl (2,4,6-TPV), has been investigated here. It was previously interpreted as an AAF system from observed susceptibility data [Tomiyoshi et al., Phys. Rev. B 49, 16031 (1994)]. The trend of the temperature dependence of magnetic susceptibility studied in the present work also indicates that the crystal belongs to the AAF category with a less prominent FM exchange coupling constant. To reinforce our conclusions, we have adopted a two-pronged strategy. First, the geometry of the 2,4,6-TPV monomer has been optimized here by ab initio unrestricted Hartree-Fock (UHF) calculations using the STO-3G basis set. The optimized geometry is almost planar. A subsequent calculation has been carried out with the phenyl rings twisted out of the plane of the nitrogen atoms. The STO-3G optimized geometry, and the same geometry except for the twisted phenyl rings, have been used to perform ab initio coupled-cluster (UCCSD-T) calculations with the same basis, and UHF as well as density-functional (UB3LYP) calculations using the 6-31G basis set. The calculated data can easily rationalize the twists while the species remains in crystal. The

  16. Synchrotron-based X-ray diffraction of the lead apatites series Pb10(PO4)6Cl2-Pb10(AsO4)6Cl2

    NASA Astrophysics Data System (ADS)

    Borkiewicz, O.; Flis, J.; Strycharczyk, M.; Manecki, M.; Bajda, T.

    2009-04-01

    Pyromorphite Pb10(PO4)6Cl2 and mimetite Pb10(AsO4)6Cl2, members of the apatite group minerals, have recently gained considerable attention as a metal sequestration agents in water treatment and contaminated soil remediation. The unique crystal structure and chemistry of those minerals allows for numerous substitutions of both metal cations and anionic complexes. The vast majority of studies conducted to date, however focused on the cationic substitutions in these minerals. Little is known about the response of the structure to anionic substitutions, which may also influence properties, stability and environmental behaviour of studied apatites. Natural pyromorphite and mimetite often exhibit certain degree of anionic substitutions, which suggests relative stability of their solid solutions in natural environment. From diffraction studies on mimetie-pyromorphite series synthesized at 60-80° C it has been found that the solid solution between these two end members is complete. The temperature of the synthesis however, renders the obtained data inapplicable to near-Earth surface environments. Furthermore, published X-ray data is not supported by the chemical analysis of precipitated solids. In order to supplement existing data, a number of compounds covering a wide range of compositions between mimetite-pyromorphite end members were synthesized by drop-wise mixing of the respective chemical reagents at room temperature. Products were characterized by SEM coupled with EDS as well as synchrotron-based X-ray diffraction. Diffraction experiments were carried on the dedicated high-resolution high-throughput powder diffractometer at Sector 11-BM B of the Advanced Photon Source, Argonne National Laboratory, USA. Analyses were performed at room temperature using monochromatic radiation of the wavelength of 0.42 Å. Intensities of the diffracted X-rays were collected on a 12-element Analyzer/Detector System offering supreme resolution and greatly reduced data collecting time

  17. Nutritional status survey of children with autism and typically developing children aged 4-6 years in Heilongjiang Province, China.

    PubMed

    Sun, Caihong; Xia, Wei; Zhao, Yan; Li, Nannan; Zhao, Dong; Wu, Lijie

    2013-01-01

    Autism is a neurodevelopmental disability that may affect nutritional management of children with autism. This study aimed to compare the nutritional status of children with autism with that of typically developing children (aged 4-6 years) in China. Nutritional status was assessed by means of nutritional data, anthropometric data, biochemical assessment, physical examination for nutrient deficiencies and providing a questionnaire to parents. A total of fifty-three children with autism and fifty-three typically developing children were enrolled in this study. The parents were asked to complete the questionnaire regarding the eating behaviour and gastrointestinal symptoms of their children. They were also asked to provide a 3 d food diary. Children with autism exhibited several abnormalities in terms of eating behaviour and gastrointestinal symptoms. The levels of vitamins A and B6, Zn and Ca intakes were <80 % of the dietary reference intakes in both groups. In addition, the proportions of vitamin C and Ca intake deficiencies in the autism group were significantly higher than those in the control group. Serum Zn level was less than the normal reference range in both the groups. Serum Ca, vitamin A and folate levels in children with autism were significantly lower when compared with children without autism. According to the anthropometric data, the mean BMI, weight-for-height Z-score (Z WH) and BMI for age Z-score (Z BMIA) of children with autism were significantly higher than those of the typically developing children. Thus, nutritional inadequacies were observed in children with autism and typically developing children in China, which were, however, more pronounced among children with autism.

  18. Transformation of 2,4,6-Trinitrotoluene by Pseudomonas pseudoalcaligenes JS52.

    PubMed

    Fiorella, P D; Spain, J C

    1997-05-01

    Pseudomonas pseudoalcaligenes JS52 grows on nitrobenzene via partial reduction of the nitro group and enzymatic rearrangement of the resultant hydroxylamine. Cells and cell extracts of nitrobenzene-grown JS52 catalyzed the transient formation of 4-hydroxylamino-2,6-dinitrotoluene (4HADNT), 4-amino-2,6-dinitrotoluene (4ADNT), and four previously unidentified metabolites from 2,4,6-trinitrotoluene (TNT). Two of the novel metabolites were identified by liquid chromatography/mass spectrometry and (sup1)H-nuclear magnetic resonance spectroscopy as 2,4-dihydroxylamino-6-nitrotoluene (DHANT) and 2-hydroxylamino-4-amino-6-nitrotoluene (2HA4ANT). A polar yellow metabolite also accumulated during transformation of TNT by cells and cell extracts. Under anaerobic conditions, extracts of strain JS52 did not catalyze the production of the yellow metabolite or release nitrite from TNT; moreover, DHANT and 2HA4ANT accumulated under anaerobic conditions, which indicated that their further metabolism was oxygen dependent. Small amounts of nitrite were released during transformation of TNT by strain JS52. Sustained transformation of TNT by cells required nitrobenzene, which indicated that TNT transformation does not provide energy. Transformation of TNT catalyzed by enzymes in cell extracts required NADPH. Transformation experiments with (sup14)C-TNT indicated that TNT was not mineralized; however, carbon derived from TNT became associated with cells. Nitrobenzene nitroreductase purified from strain JS52 transformed TNT to DHANT via 4HADNT, which indicated that the nitroreductase could catalyze the first two steps in the transformation of TNT. The unusual ability of the nitrobenzene nitroreductase to catalyze the stoichiometric reduction of aromatic nitro compounds to the corresponding hydroxylamine provides the basis for the novel pathway for metabolism of TNT.

  19. Transformation of 2,4,6-Trinitrotoluene by Pseudomonas pseudoalcaligenes JS52

    PubMed Central

    Fiorella, P. D.; Spain, J. C.

    1997-01-01

    Pseudomonas pseudoalcaligenes JS52 grows on nitrobenzene via partial reduction of the nitro group and enzymatic rearrangement of the resultant hydroxylamine. Cells and cell extracts of nitrobenzene-grown JS52 catalyzed the transient formation of 4-hydroxylamino-2,6-dinitrotoluene (4HADNT), 4-amino-2,6-dinitrotoluene (4ADNT), and four previously unidentified metabolites from 2,4,6-trinitrotoluene (TNT). Two of the novel metabolites were identified by liquid chromatography/mass spectrometry and (sup1)H-nuclear magnetic resonance spectroscopy as 2,4-dihydroxylamino-6-nitrotoluene (DHANT) and 2-hydroxylamino-4-amino-6-nitrotoluene (2HA4ANT). A polar yellow metabolite also accumulated during transformation of TNT by cells and cell extracts. Under anaerobic conditions, extracts of strain JS52 did not catalyze the production of the yellow metabolite or release nitrite from TNT; moreover, DHANT and 2HA4ANT accumulated under anaerobic conditions, which indicated that their further metabolism was oxygen dependent. Small amounts of nitrite were released during transformation of TNT by strain JS52. Sustained transformation of TNT by cells required nitrobenzene, which indicated that TNT transformation does not provide energy. Transformation of TNT catalyzed by enzymes in cell extracts required NADPH. Transformation experiments with (sup14)C-TNT indicated that TNT was not mineralized; however, carbon derived from TNT became associated with cells. Nitrobenzene nitroreductase purified from strain JS52 transformed TNT to DHANT via 4HADNT, which indicated that the nitroreductase could catalyze the first two steps in the transformation of TNT. The unusual ability of the nitrobenzene nitroreductase to catalyze the stoichiometric reduction of aromatic nitro compounds to the corresponding hydroxylamine provides the basis for the novel pathway for metabolism of TNT. PMID:16535610

  20. 4',6-diamidino-2-phenylindole (DAPI) interacts with rare structures of GC polymers.

    PubMed

    Barcellona, M L; Chen, Y; Müller, J D; Gratton, E

    2001-01-01

    The binding of 4',6-diamidino-2-phenylindole (DAPI) to double-stranded GC polymers either in the alternating or in homopolymer sequence was investigated using fluorescence techniques. We employed fluctuation correlation spectroscopy, which measures the diffusion coefficient of fluorescent particles, to demonstrate that the fluorescence was originating from relatively slowly diffusing entities. These entities display a very large heterogeneity of diffusing coefficients, indicating that molecular aggregation is extensive in our samples. We used frequency domain fluorometry to characterize the fluorescence lifetime of the species, while varying the GC polymer-dye coverage systematically. At very low coverage we observed a relatively bright fluorescent component with a lifetime value of approximately 4 ns. The stoichiometry of binding of this bright species was such that it can only arise from rare molecular structures, either unusual loops or large molecular aggregates. The amount and characteristics of this bright fluorescent component were different between the homo and the alternating polymer, indicating that the difference in sequence of the two polymers is responsible for the different aggregates which are then detected in the fluorescence experiment. At large GC polymer coverage we observed a relatively wide distribution of fluorescent species with short lifetime values, in the range between 0.12 and 0.2 ns. Given the stoichiometry of binding of this fluorescent component, we concluded that it could arise either from intercalative and/or non-specific binding to the DNA double-stranded molecules. We comment on the origin of the rare but brightly fluorescent binding sites and discuss the potential to detect such unusual DNA structures.

  1. Hydrogen-bonded supramolecular motifs in 2-amino-4,6-dimethoxypyrimidinium 4-hydroxybenzoate monohydrate, 2-amino-4,6-dimethoxypyrimidinium 6-carboxypyridine-2-carboxylate monohydrate and 2-amino-4,6-dimethoxypyrimidinium hydrogen (2R,3R)-tartrate 2-amino-4,6-dimethoxypyrimidine.

    PubMed

    Thanigaimani, Kaliyaperumal; Muthiah, Packianathan Thomas; Lynch, Daniel E

    2007-05-01

    In the crystal structures of the title compounds, C(6)H(10)N(3)O(2)+.C(7)H(5)O(3)-.H2O, (I), C(6)H(10)N(3)O(2)+.C(7)H(4)NO(4)-.H2O, (II), and C(6)H(10)N(3)O(2)+.C(4)H(5)O(6)-.C(6)H(9)N(3)O(2), (III), the 2-amino-4,6-dimethoxypyrimidinium cation [abbreviated as (MeO)2-Hampy+] interacts with the carboxylate group of the corresponding anion through a pair of nearly parallel N-H...O hydrogen bonds to form R(2)(2)(8) ring motifs. In (I), the (MeO)2-Hampy+ cation is centrosymmetrically paired through a pair of N-H...N hydrogen bonds involving the 2-amino group and a ring N atom forming an R(2)(2)(8) motif. In (II), inversion-related R(2)(2)(8) motifs (amino-pyrimidine-carboxylate motifs) are further bridged by N-H...O hydrogen bonds on either side forming a DDAA array of quadruple hydrogen bonds. This array is extended further on either side by O(water)-H...O(methoxy) hydrogen bonds, resulting in an array of six hydrogen bonds (ADDAAD). The water molecule plays a pivotal role, and five hydrogen-bonded fused rings are formed around the water molecule. In (III), the carboxy group of the tartrate anion interacts with the ring N atom and 2-amino group of the neutral (MeO)2-ampy molecule through N-H...O and O-H...N hydrogen bonds. There is also an intramolecular O-H...O hydrogen bond in the tartrate anion. In all three crystal structures, C-H...O hydrogen bonds are observed.

  2. Dual Role of Endogenous Serotonin in 2,4,6-Trinitrobenzene Sulfonic Acid-Induced Colitis

    PubMed Central

    Rapalli, Alberto; Bertoni, Simona; Arcaro, Valentina; Saccani, Francesca; Grandi, Andrea; Vivo, Valentina; Cantoni, Anna M.; Barocelli, Elisabetta

    2016-01-01

    Background and Aims: Changes in gut serotonin (5-HT) content have been described in Inflammatory Bowel Disease (IBD) and in different experimental models of colitis: the critical role of this monoamine in the pathogenesis of chronic gastrointestinal inflammation is gradually emerging. Aim of the present study was to evaluate the contribution of endogenous 5-HT through the activation of its specific receptor subtypes to the local and systemic inflammatory responses in an experimental model of IBD. Materials and Methods: Colitis was induced by intrarectal 2,4,6-TriNitroBenzene Sulfonic acid in mice subacutely treated with selective antagonists of 5-HT1A (WAY100135), 5-HT2A (Ketanserin), 5-HT3 (Ondansetron), 5-HT4 (GR125487), 5-HT7 (SB269970) receptors and with 5-HT1A agonist 8-Hydroxy-2-(di-n-propylamino)tetralin. Results: Blockade of 5-HT1A receptors worsened TNBS-induced local and systemic neutrophil recruitment while 5-HT1A agonist delayed and mitigated the severity of colitis, counteracting the increase in colonic 5-HT content. On the contrary, blockade of 5-HT2A receptors improved global health conditions, reduced colonic morphological alterations, down-regulated neutrophil recruitment, inflammatory cytokines levels and colonic apoptosis. Antagonism of 5-HT3, 5-HT4, and 5-HT7 receptor sites did not remarkably affect the progression and outcome of the pathology or only slightly improved it. Conclusion: The prevailing deleterious contribution given by endogenous 5-HT to inflammation in TNBS-induced colitis is seemingly mediated by 5-HT2A and, to a lesser extent, by 5-HT4 receptors and coexists with the weak beneficial effect elicited by 5-HT1A stimulation. These findings suggest how only a selective interference with 5-HT pro-inflammatory actions may represent an additional potential therapeutic option for intestinal inflammatory disorders. PMID:27047383

  3. Measurements of coronal Faraday rotation at 4.6 R {sub ☉}

    SciTech Connect

    Kooi, Jason E.; Fischer, Patrick D.; Buffo, Jacob J.; Spangler, Steven R.

    2014-03-20

    Many competing models for the coronal heating and acceleration mechanisms of the high-speed solar wind depend on the solar magnetic field and plasma structure in the corona within heliocentric distances of 5 R {sub ☉}. We report on sensitive Very Large Array (VLA) full-polarization observations made in 2011 August, at 5.0 and 6.1 GHz (each with a bandwidth of 128 MHz) of the radio galaxy 3C 228 through the solar corona at heliocentric distances of 4.6-5.0 R {sub ☉}. Observations at 5.0 GHz permit measurements deeper in the corona than previous VLA observations at 1.4 and 1.7 GHz. These Faraday rotation observations provide unique information on the magnetic field in this region of the corona. The measured Faraday rotation on this day was lower than our a priori expectations, but we have successfully modeled the measurement in terms of observed properties of the corona on the day of observation. Our data on 3C 228 provide two lines of sight (separated by 46'', 33,000 km in the corona). We detected three periods during which there appeared to be a difference in the Faraday rotation measure between these two closely spaced lines of sight. These measurements (termed differential Faraday rotation) yield an estimate of 2.6-4.1 GA for coronal currents. Our data also allow us to impose upper limits on rotation measure fluctuations caused by coronal waves; the observed upper limits were 3.3 and 6.4 rad m{sup –2} along the two lines of sight. The implications of these results for Joule heating and wave heating are briefly discussed.

  4. Bioremediation of 2,4,6-trinitrotoluene by bacterial nitroreductase expressing transgenic aspen.

    PubMed

    Van Dillewijn, Pieter; Couselo, José L; Corredoira, Elena; Delgado, Antonio; Wittich, Rolf-Michael; Ballester, Antonio; Ramos, Juan L

    2008-10-01

    Trees belonging to the genus Populus are often used for phytoremediation due to their deep root formation, fast growth and high transpiration rates. Here, we study the capacity of transgenic hybrid aspen (Populus tremula x tremuloides var. Etropole) which expresses the bacterial nitroreductase gene, pnrA, to tolerate and take-up greater amounts of the toxic and recalcitrant explosive, 2,4,6-trinitrotoluene (TNT) from contaminated waters and soil. Transgenic aspen tolerate up to 57 mg TNT/L in hydroponic media and more than 1000 mg TNT/ kg soil, whereas the parental aspen could not endure in hydroponic culture with more than 11 mg TNT/L or soil with more than 500 mg TNT/kg. Likewise, the phytotoxicological limit for transgenic plants to a constant concentration of TNT was 20 mg TNT/L while wild-type plants only tolerated 10 mg TNT/L. Transgenic plants also showed improved uptake of TNT over wild-type plants when the original TNT concentration was above 35 mg TNT/L in liquid media or 750 mg TNT/kg in soil. Assays with 13C-labeled TNT show rapid adsorption of TNT to the root surface followed by a slower entrance rate into the plant. Most of the 13C-carbon from the labeled TNT taken up bythe plant (> 95%) remains in the root with little translocation to the stem. Altogether, transgenic aspen expressing pnrA are highly interesting for phytoremediation applications on contaminated soil and underground aquifers.

  5. Identification of urinary metabolites of 2,4,6-trinitrotoluene in rats by liquid chromatography-mass spectometry.

    PubMed

    Yinon, J; Hwang, D G

    1985-08-01

    Metabolites of 2,4,6-trinitrotoluene (TNT) were found in the urine of rats fed with TNT. The urine extracts were analysed by liquid chromatography-mass spectrometry (LC-MS). Metabolites found included TNT itself as well as 2-amino-4,6-dinitrotoluene, 4-amino-2,6-dinitrotoluene and 2,4-diamino-6-nitrotoluene, indicating that reduction processes are responsible for the formation of these metabolites.

  6. Preparation and properties of piperidine salts of 6-hydroxy-4,6-diaryl-5-ethoxycarbonyl-3-cyanopiperidine-2-thiones

    SciTech Connect

    Krauze, A.A.; Liepin'sh, E.E.; Pelcher, Yu.E.; Kalme, Z.A.; Dubur, G.Ya.

    1987-07-01

    Alkylation of piperidine salts of 6-hydroxy-4,6-diaryl-5-ethoxycarbonyl-3-cyanopiperidine-2(1H)-thiones yielded 6-hydroxy-2-alkylthio-4,6-diaryl-5-ethoxycarbonyl-1-3-cyano-3,4,5,6-tetrahydropyridines which were dehydrogenated with the formation of 2-methylthio-1,4- and 4,5-dihydropyridines. The oxidation of the compounds prepared has been studied.

  7. Preliminary kinetics and metabolism of 2,4,6-trinitrotoluene and its reduced metabolites in an aquatic oligochaete.

    PubMed

    Conder, Jason M; Point, Thomas W La; Bowen, Alethea T

    2004-08-25

    We examined the toxicokinetics and metabolism of 2,4,6-trinitirotoluene (TNT) and four of its major reduced metabolites (2-amino-4,6-dinitrotoluene (2ADNT), 4-amino-2,6-dinitrotoluene (4ADNT), and 2,4-diamino-6-nitrotoluene (2,4DANT)) in the freshwater, aquatic oligochaete Tubifex tubifex exposed to spiked, reconstituted water. In uptake experiments with each compound, steady state concentrations were reached within 1h, and all absorbed compounds were completely eliminated in 0-3 h. The appearance of 2ADNT and 4ADNT (from metabolism of absorbed TNT) was five times slower, reaching 95% of steady state in 14.2-16.1h. Approximately, 82% of absorbed TNT was metabolized to ADNTs; metabolism to 4ADNT was favored over 2ADNT by a factor of 3. No further metabolism of ADNTs to DANTs was detected. After a loss of 29-50% of metabolically-generated ADNTs during the first hour of the TNT depuration experiment, Tubifex ADNT concentrations remained constant throughout the 53h depuration period. This suggests differences between the toxicokinetics of absorbed ADNTs and the toxicokinetics of metabolically-generated ADNTs. Experiments using radiolabeled (14C) TNT revealed that only 15-47% of 14C-TNT equivalents were identified as TNT, 2ADNT, or 4ADNT, indicating significant metabolism and/or binding to biomolecules. Of unidentified 14C-TNT equivalents, 28-38% remained unextractable. Both unextractable and extractable unidentified substances increased throughout the 54 h 14C-TNT uptake experiment. The unidentified portions of the radiolabel were not eliminated during a 53-h depuration experiment. Bioconcentration factors (BCFs) for HPLC-detectable compounds were found to be linearly related to log K(OW) (r2 = 0.9963). BCFs for 2ADNT, 4ADNT, and 2,4DANT were 10.22, 12.41, and 2.75, respectively. The BCF for TNT was 12.25, based on a molar sum of total TNT and its metabolites (SigmaTNT + 2ADNT + 4ADNT), and 2.53 based on TNT only. Compound hydrophobicity predicted the toxicokinetics

  8. Identification and modulatory activity assessment of 2-hydroxy-3,4,6-trimethoxyacetophenone isolated from croton anisodontus müll. Arg.(euphorbiaceae).

    PubMed

    Oliveira, Maria T A; Teixeira, Alexandre M R; Coutinho, Henrique D M; Menezes, Irwin R A; Sena, Diniz M; Santos, Hélcio S; de Mesquita, Bruna M; Albuquerque, Maria R J R; Bandeira, Paulo N; Braz-Filho, Raimundo

    2014-05-01

    The n-hexane extract of the stem bark of Croton anisodontus yielded 2-hydroxy-3,4,6-trimethoxyacetophenone, a well-known substance, but isolated from this species for the first time. The antimicrobial and modulatory activities of the compound towards Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans, C. krusei and C. tropicalis strains were assessed. Antibiotics such as amikacin, gentamicin and neomycin were used in a sub-inhibitory concentration. Significant activity was observed towards P. aeruginosa and S. aureus 358, with p < 0.001 in association with amikacin. The present results place C anisodontus as an alternative source of 2-hydroxy-3,4,6-trimethoxyacetophenone with antibacterial potential.

  9. Extraction-less, rapid assay for the direct detection of 2,4,6-trichloroanisole (TCA) in cork samples.

    PubMed

    Apostolou, Theofylaktos; Pascual, Nuria; Marco, M-Pilar; Moschos, Anastassios; Petropoulos, Anastassios; Kaltsas, Grigoris; Kintzios, Spyridon

    2014-07-01

    2,4,6-trichloroanisole (TCA), the cork taint molecule, has been the target of several analytical approaches over the few past years. In spite of the development of highly efficient and sensitive tools for its detection, ranging from advanced chromatography to biosensor-based techniques, a practical breakthrough for routine cork screening purposes has not yet been realized, in part due to the requirement of a lengthy extraction of TCA in organic solvents, mostly 12% ethanol and the high detectability required. In the present report, we present a modification of a previously reported biosensor system based on the measurement of the electric response of cultured fibroblast cells membrane-engineered with the pAb78 TCA-specific antibody. Samples were prepared by macerating cork tissue and mixing it directly with the cellular biorecognition elements, without any intervening extraction process. By using this novel approach, we were able to detect TCA in just five minutes at extremely low concentrations (down to 0.2 ppt). The novel biosensor offers a number of practical benefits, including a very considerable reduction in the total assay time by one day, and a full portability, enabling its direct employment for on-site, high throughput screening of cork in the field and production facilities, without requiring any type of supporting infrastructure.

  10. Construction of 2,4,6-Trinitrotoluene Biosensors with Novel Sensing Elements from Escherichia coli K-12 MG1655.

    PubMed

    Tan, Junjie; Kan, Naipeng; Wang, Wei; Ling, Jingyi; Qu, Guolong; Jin, Jing; Shao, Yu; Liu, Gang; Chen, Huipeng

    2015-06-01

    Detection of 2,4,6-trinitrotoluene (TNT) has been extensively studied since it is a common explosive filling for landmines, posing significant threats to the environment and human safety. The rapid advances in synthetic biology give new hope to detect such toxic and hazardous compounds in a more sensitive and safe way. Biosensor construction anticipates finding sensing elements able to detect TNT. As TNT can induce some physiological responses in E. coli, it may be useful to define the sensing elements from E. coli to detect TNT. An E. coli MG1655 genomic promoter library containing nearly 5,400 elements was constructed. Five elements, yadG, yqgC, aspC, recE, and topA, displayed high sensing specificity to TNT and its indicator compounds 1,3-DNB and 2,4-DNT. Based on this, a whole cell biosensor was constructed using E. coli, in which green fluorescent protein was positioned downstream of the five sensing elements via genetic fusion. The threshold value, detection time, EC200 value, and other aspects of five sensing elements were determined and the minimum responding concentration to TNT was 4.75 mg/L. According to the synthetic biology, the five sensing elements enriched the reservoir of TNT-sensing elements, and provided a more applicable toolkit to be applied in genetic routes and live systems of biosensors in future.

  11. Structural Studies of FlaA1 from Helicobacter Pylori Reveal the Mechanism for Inverting 4,6-dehydratase Activity

    SciTech Connect

    Ishiyama,N.; Creuzenet, C.; Miller, W.; Demendi, M.; Anderson, E.; Harauz, G.; Lam, J.; Berghuis, A.

    2006-01-01

    FlaA1 from the human pathogen Helicobacter pylori is an enzyme involved in saccharide biosynthesis that has been shown to be essential for pathogenicity. Here we present five crystal structures of FlaA1 in the presence of substrate, inhibitors, and bound cofactor, with resolutions ranging from 2.8 to 1.9 {angstrom}. These structures reveal that the enzyme is a novel member of the short-chain dehydrogenase/reductase superfamily. Additional electron microscopy studies show the enzyme to possess a hexameric doughnut-shaped quaternary structure. NMR analyses of 'real time' enzyme-substrate reactions indicate that FlaA1 is a UDP-GlcNAc-inverting 4,6-dehydratase, suggesting that the enzyme catalyzes the first step in the biosynthetic pathway of a pseudaminic acid derivative, which is implicated in protein glycosylation. Guided by evidence from site-directed mutagenesis and computational simulations, a three-step reaction mechanism is proposed that involves Lys-133 functioning as both a catalytic acid and base.

  12. Disposition of 1,4,6,8-tetramethyl-furoquinolinone in normal and ascitic tumor bearing mice.

    PubMed

    Bevilacqua, Rita; Baccichetti, Francarosa; Gaion, Rosa Maria; Guiotto, Adriano

    2006-01-01

    1,4,6,8-Tetramethyl-2H-furo[2,3h]quinolin-2-one (FQ) belongs to a series of furocoumarin isosters, designed to obtain new drugs for photochemotherapy. The objective of this study was to characterize the disposition of orally administered 3H-FQ in normal and ascitic tumor bearing mice and to evaluate the influence of UVA irradiation in control mice. This compound was rapidly absorbed and its decay in serum was biphasic. Binding to serum proteins, which was maximum at 30 min (74 %), time-dependently declined. FQ was distributed to all the studied tissues, primarily to the liver and kidneys. The administered radioactivity was excreted mostly in the urine (43 %) and was associated with polar metabolites. The unchanged compound was not present to any detectable extent in the urine. Elimination in the faeces, that may include FQ not absorbed, was low (14 % of administered radioactivity), emphasizing the quantitatively efficient gastrointestinal absorption of the drug. UVA irradiation of FQ-treated mice for 2 h caused a significant increase in radioactivity measured in serum as well as in the liver. In mice bearing Ehrlich ascitic tumor, serum and tissue concentrations were lower than in control animals, possibly due to the larger volume of body fluids (10+/-4 ml of ascitic fluid) available for drug distribution.

  13. Adsorption of 2,4,6-trinitrotoluene and 4-amino-2,6-dinitrotoluene in two soil environments

    SciTech Connect

    Wood, A.J.; Tiller, C.L.

    1996-10-01

    Soil contamination by 2,4,6-trinitrotoluene (TNT) and its byproducts is common among Army Ammunition Plants (AAPs). The purpose of this research is to quantify the behavior of TNT in the Alabama AAP soil environment. Uncontaminated soil collected from two different depths at the site was used, one with relatively high organic content and one with low organic content. Adsorption kinetic tests for both TNT and a primary biotransformation byproduct 4-amino-2,6-dinitrotoluene (4A26DNT), alone and in combination, were performed and adsorption isotherms were developed. Results indicate a faster rate of adsorption for 4A26DNT than for TNT, as well as a larger extent of adsorption when the two compounds are both present. As expected, incubation time was shown to affect the extent of adsorption as well as the extractability and transformation of TNT. Large differences in kinetic patterns were obtained for each soil. Isotherm shape was similar for both soils, however extent of adsorption differed by several orders of magnitude.

  14. Expression of glutathione S-transferases in poplar trees (Populus trichocarpa) exposed to 2,4,6-trinitrotoluene (TNT).

    PubMed

    Brentner, Laura B; Mukherji, Sachiyo T; Merchie, Kate M; Yoon, Jong Moon; Schnoor, Jerald L; Van Aken, Benoit

    2008-10-01

    Twelve Populus genes were identified from Arabidopsis thaliana sequences previously shown to be induced by exposure to 2,4,6-trinitrotoluene (TNT). Using the resources of the Poplar Genome Project and National Center for Biotechnology Information databases, Populus conserved domains were identified and used to design gene specific primers. RNA extracted from root tissues of TNT-exposed hydroponic poplar plants was used to quantify the expression of genes by reverse-transcriptase real-time polymerase chain reaction. Cyclophilin and 18S ribosomal DNA genes were used as internal standards. Exposure to TNT resulted in a significant increase of gene expression of two glutathione S-transferases (GST), peaking at levels of 25.0 +/- 13.1 and 10 +/- 0.7 fold the expression level of non-exposed plants after 24 h for each of the GST genes, respectively. This paper demonstrates the use of functional genomics information from the model plant species, Arabidopsis, to identify genes which may be important in detoxification of TNT in the model phytoremediation species, Populus trichocarpa.

  15. Spectroscopic studies on ligand-enzyme interactions: complexation of alpha-chymotrypsin with 4',6-diamidino-2-phenylindole (DAPI).

    PubMed

    Banerjee, Debapriya; Srivastava, Sachin Kumar; Pal, Samir Kumar

    2008-02-14

    In the present study, the interaction of two structurally related proteolytic enzymes trypsin and alpha-chymotrypsin (CHT) with 4',6-Diamidino-2-phenylindole (DAPI) has been addressed. The binding of DAPI to CHT has been characterized by steady-state and picosecond time-resolved spectroscopic techniques. Enzymatic activity of CHT and simultaneous binding of the well-known inhibitor proflavin (PF) in the presence of DAPI clearly rule out the possibility of DAPI binding at the catalytic site of the enzyme. The spectral overlap between the emission of DAPI and absorption of PF offers the opportunity to explore the binding site of DAPI using Förster resonance energy transfer (FRET). FRET studies between DAPI and PF indicate that DAPI is bound to CHT with its transition dipole nearly perpendicular to that of PF. Competitive binding of DAPI with another fluorescent probe 2,6-p-toluidinonaphthalene sulfonate (TNS), having a well-defined binding site, indicates that DAPI and TNS bind at the same hydrophobic site of the enzyme CHT. The difference in the interactions of two well-studied, structurally similar enzymes with the same molecule may find its application in the design of specific substrate mimics or inhibitors of the enzymes.

  16. Analysis of 2,4,6-nonatrienal geometrical isomers from male flea beetles, Epitrix hirtipennis and E. fuscula.

    PubMed

    Zilkowski, Bruce W; Bartelt, Robert J; Vermillion, Karl

    2008-07-09

    Geometrical isomers of 2,4,6-nonatrienal have been reported from a variety of food- and insect-related sources. It was discovered recently that the eggplant flea beetle, Epitrix fuscula, uses the (2 E,4 E,6 Z) and (2 E,4 E,6 E) isomers as components of its male-produced aggregation pheromone. Here, we learned that the related species, E. hirtipennis, also emits a blend of 2,4,6-nonatrienals, including isomers not previously characterized. Patterns in emission and response suggest a pheromonal function. In an effort to acquire standards to aid in identification, we found that exposing (2 E,4 E,6 E)-2,4,6-nonatrienal (or other available 2,4,6-nonatrienals) to light readily generated a mixture of six geometrical isomers. Configurations of these were determined by NMR, and chromatographic properties (GC and HPLC) were documented. On the basis of chromatographic comparison to these standards, the most abundant, new compound from E. hirtipennis was concluded to be (2 E,4 Z,6 Z)-2,4,6-nonatrienal. Minor components from both E. hirtipennis and E. fuscula were also characterized. The analytical approach given here would also be of use in the food industry, where 2,4,6-nonatrienals are important as aroma compounds.

  17. Application of Novel Amino-Functionalized NZVI@SiO2 Nanoparticles to Enhance Anaerobic Granular Sludge Removal of 2,4,6-Trichlorophenol

    PubMed Central

    Guan, Zeyu; Wan, Jinquan; Ma, Yongwen; Wang, Yan; Shu, Yajie

    2015-01-01

    A novel amino-functionalized silica-coated nanoscale zerovalent iron (NZVI@SiO2-NH2) was successfully synthesized by using one-step liquid-phase method with the surface functionalization of nanoscale zerovalent iron (NZVI) to enhance degradation of chlorinated organic contaminants from anaerobic microbial system. NZVI@SiO2-NH2 nanoparticles were synthesized under optimal conditions with the uniform core-shell structure (80–100 nm), high loading of amino functionality (~0.9 wt%), and relatively large specific surface area (126.3 m2/g). The result demonstrated that well-dispersed NZVI@SiO2-NH2 nanoparticle with nFe0-core and amino-functional silicon shell can effectively remove 2,4,6-trichlorophenol (2,4,6-TCP) in the neutral condition, much higher than that of NZVI. Besides, the surface-modified nanoparticles (NZVI@SiO2-NH2) in anaerobic granule sludge system also showed a positive effect to promote anaerobic biodechlorination system. More than 94.6% of 2,4,6-TCP was removed from the combined NZVI@SiO2-NH2-anaerobic granular sludge system during the anaerobic dechlorination processes. Moreover, adding the appropriate concentration of NZVI@SiO2-NH2 in anaerobic granular sludge treatment system can decrease the toxicity of 2,4,6-TCP to anaerobic microorganisms and improved the cumulative amount of methane production and electron transport system activity. The results from this study clearly demonstrated that the NZVI@SiO2-NH2/anaerobic granular sludge system could become an effective and promising technology for the removal of chlorophenols in industrial wastewater. PMID:26060427

  18. Application of Novel Amino-Functionalized NZVI@SiO2 Nanoparticles to Enhance Anaerobic Granular Sludge Removal of 2,4,6-Trichlorophenol.

    PubMed

    Guan, Zeyu; Wan, Jinquan; Ma, Yongwen; Wang, Yan; Shu, Yajie

    2015-01-01

    A novel amino-functionalized silica-coated nanoscale zerovalent iron (NZVI@SiO2-NH2) was successfully synthesized by using one-step liquid-phase method with the surface functionalization of nanoscale zerovalent iron (NZVI) to enhance degradation of chlorinated organic contaminants from anaerobic microbial system. NZVI@SiO2-NH2 nanoparticles were synthesized under optimal conditions with the uniform core-shell structure (80-100 nm), high loading of amino functionality (~0.9 wt%), and relatively large specific surface area (126.3 m(2)/g). The result demonstrated that well-dispersed NZVI@SiO2-NH2 nanoparticle with nFe(0)-core and amino-functional silicon shell can effectively remove 2,4,6-trichlorophenol (2,4,6-TCP) in the neutral condition, much higher than that of NZVI. Besides, the surface-modified nanoparticles (NZVI@SiO2-NH2) in anaerobic granule sludge system also showed a positive effect to promote anaerobic biodechlorination system. More than 94.6% of 2,4,6-TCP was removed from the combined NZVI@SiO2-NH2-anaerobic granular sludge system during the anaerobic dechlorination processes. Moreover, adding the appropriate concentration of NZVI@SiO2-NH2 in anaerobic granular sludge treatment system can decrease the toxicity of 2,4,6-TCP to anaerobic microorganisms and improved the cumulative amount of methane production and electron transport system activity. The results from this study clearly demonstrated that the NZVI@SiO2-NH2/anaerobic granular sludge system could become an effective and promising technology for the removal of chlorophenols in industrial wastewater.

  19. Game Times and Higher Winning Percentages of West Coast Teams of the National Football League Correspond With Reduced Prevalence of Regular Season Injury.

    PubMed

    Brager, Allison J; Mistovich, Ronald J

    2017-02-01

    Brager, AJ and Mistovich, RJ. Game times and higher winning percentages of west coast teams of the National Football League correspond with reduced prevalence of regular season injury. J Strength Cond Res 31(2): 462-467, 2017-West coast teams of the National Football League are more statistically likely to win home night games against east coast opponents. The alignment of game times with daily rhythms of alertness is thought to contribute to this advantage. This study aims to determine whether rates of turnovers and injuries during the regular season, putative measures of mental and physical fatigue, impact winning percentages. Regular season schedules and rates of turnovers for each of the 32 teams were obtained from Pro-Football-Reference. We developed our own metric of injury risk for each position obtained from depth charts and regular season schedules. This metric compared cumulative weeks on injury reserve with cumulative time zone travel. West coast teams traveled 4 times as often as east coast teams. However, teams traveling eastward won twice as many games. There was no relationship between the extent and direction of travel and number of turnovers. Losing teams had more turnovers. The offensive and defensive lines in Central Time (CT) were placed on injury reserve 4 times as often as offensive and defensive lines in Pacific Time (PT). Injury prevalence in CT vs. PT was most prominent midseason. Plotting midseason game time relative to biological time revealed that PT teams play games closer to endogenous peaks in alertness, whereas CT teams play games closer to endogenous troughs in alertness. Overall, closer alignment of game time with the endogenous "alerting" signal may protect west coast teams from fatigue-related injuries and suggests for modified strength and conditioning programs.

  20. Large-Scale Synthesis of Crystalline 1,2,3,4,6,7-Hexa-O-acetyl-l-glycero-α-d-manno-heptopyranose

    PubMed Central

    Stanetty, Christian; Baxendale, Ian R

    2015-01-01

    The higher-carbon sugar l-glycero-d-manno-heptose is a major constituent of the inner core region of the lipopolysaccharide (LPS) of many Gram-negative bacteria. All preparative routes used to date require multiple steps, and scalability has been rarely addressed. Here a highly practical synthesis of crystalline 1,2,3,4,6,7-hexa-O-acetyl-l-glycero-α-d-manno-heptopyranose by a simple four-step sequence starting from l-lyxose is disclosed. Only two recrystallisations are required and the process was demonstrated on a >100 mmol scale, yielding 41 g of the target compound. PMID:26097405

  1. Chronic Kidney Disease Is Characterized by “Double Trouble” Higher Pulse Pressure plus Night-Time Systolic Blood Pressure and More Severe Cardiac Damage

    PubMed Central

    Fedecostante, Massimiliano; Spannella, Francesco; Cola, Giovanna; Espinosa, Emma; Dessì-Fulgheri, Paolo; Sarzani, Riccardo

    2014-01-01

    Background Hypertension plays a key role in chronic kidney disease (CKD), but CKD itself affects the blood pressure (BP) profile. The aim of this study was to assess the association of BP profile with CKD and the presence of cardiac organ damage. Methods We studied 1805 patients, referred to our Hypertension Centre, in whom ABPM, blood tests, and echocardiography were clinically indicated. The glomerular filtration rate was estimated (eGFR) using the MDRD equation and CKD was defined as eGFR<60 mL/min/1.73 m2. Cardiac organ damage was evaluated by echocardiography. Results Among patients with CKD there were higher systolic blood pressure (SBP) during the night-time, greater prevalence of non-dippers (OR: 1.8) and increased pulse pressure (PP) during 24-hour period, daytime and night-time (all p<0.001). Patients with CKD had a greater LVM/h2.7 index, and a higher prevalence of left ventricular hypertrophy and diastolic dysfunction (all p<0.001). Nocturnal SBP and PP correlated more strongly with cardiac organ damage (p<0.001). Patients with CKD had a greater Treatment Intensity Score (p<0.001) in the absence of a significantly greater BP control. Conclusions CKD patients have an altered night-time pressure profile and higher PP that translate into a more severe cardiac organ damage. In spite of a greater intensity of treatment in most patients with CKD, BP control was similar to patients without CKD. Our findings indicate the need of a better antihypertensive therapy in CKD, better selected drugs, dosages and posology to provide optimal coverage of 24 hours and night-time BP. PMID:24465931

  2. Younger age at initiation of the human papillomavirus (HPV) vaccination series is associated with higher rates of on-time completion.

    PubMed

    St Sauver, Jennifer L; Rutten, Lila J Finney; Ebbert, Jon O; Jacobson, Debra J; McGree, Michaela E; Jacobson, Robert M

    2016-08-01

    Vaccination rates for human papillomavirus (HPV) have remained disappointingly low. It is critical to identify methods to increase on-time vaccine series completion rates (before 13 or 15years). To determine whether younger age (9 to 10years of age) at HPV vaccine series initiation was associated with improved on-time completion rates compared to initiation at 11 to 12years, we examined the prevalence of on-time HPV vaccine series completion rates from August 2006 through December 2012 in a large, population-based cohort of children and adolescents (aged 9.5 to 27years) residing in Olmsted County, MN on December 31, 2012 (n=36,223). We compared age at vaccine initiation between individuals who successfully completed both 2 and 3 doses of the vaccination series on-time (before age 13.5 or 15.0years) using multivariate logistic regression. On-time completion of both 2 and 3 doses of the vaccine series by age 13.5 or 15.0years was significantly associated with initiation at 9 to 10years as compared to 11 to 12years after adjusting for sex, race, insurance status, frequent health care visits, and year of first vaccination (all p<.01). Interventions focused on beginning the vaccination series at 9 to 10years of age may result in higher rates of timely series completion.

  3. Dynamics of higher-order rational solitons for the nonlocal nonlinear Schrödinger equation with the self-induced parity-time-symmetric potential.

    PubMed

    Wen, Xiao-Yong; Yan, Zhenya; Yang, Yunqing

    2016-06-01

    The integrable nonlocal nonlinear Schrödinger equation with the self-induced parity-time-symmetric potential [M. J. Ablowitz and Z. H. Musslimani, Phys. Rev. Lett. 110, 064105 (2013)] is investigated, which is an integrable extension of the standard nonlinear Schrödinger equation. Its novel higher-order rational solitons are found using the nonlocal version of the generalized perturbation (1,N-1)-fold Darboux transformation. These rational solitons illustrate abundant wave structures for the distinct choices of parameters (e.g., the strong and weak interactions of bright and dark rational solitons). Moreover, we also explore the dynamical behaviors of these higher-order rational solitons with some small noises on the basis of numerical simulations.

  4. Structure and optical properties of KLa9(GeO4)6O2 and KLa8.37Eu0.63(GeO4)6O2

    NASA Astrophysics Data System (ADS)

    Lipina, Olga A.; Surat, Ludmila L.; Tyutyunnik, Alexander P.; Enyashin, Andrey N.; Chufarov, Alexander Yu.; Zubkov, Vladimir G.

    2017-01-01

    New KLa9(GeO4)6O2 and KLa8.37Eu0.63(GeO4)6O2 germanates with the apatite structure type (space group P63/m, Z = 1) have been synthesized by the sol-gel method using ethylenediaminetetraacetic acid as a precursor and characterized by powder X-ray diffraction, scanning electron microscopy and diffuse reflectance spectroscopy. Density functional theory calculations reveal that KLa9(GeO4)6O2 is a direct bandgap material, and near-UV excitation leads to the electronic transitions from the O2p- orbitals to the Lad- and K4s- states. Photoluminescence measurements of the Eu3+-doped sample indicate emission in the visible spectral range corresponding to the characteristic transitions from the excited 5D0 and 5D1 levels in europium ion.

  5. Organic-inorganic compounds with strong nonlinear optical properties based on 2,4,6-trimethylpyridinium and tetrahedral BF4- networks

    NASA Astrophysics Data System (ADS)

    Wojtaś, Maciej; Bil, Andrzej; Jakubas, Ryszard; Gągor, Anna; Pietraszko, Adam; Czupiński, Olaf; Tylczyński, Zbigniew; Isakov, Dmitry

    2011-04-01

    A different organic-inorganic crystal—[2,4,6-trimethylpyridinium][BF4]—of nonlinear optical properties at room temperature was synthesized and characterized. The compound is built up of the organic [2,4,6-trimethylpyridinium] cations incorporated into inorganic, tetrahedral BF4 anions. It crystallizes at room temperature in the polar space group Pmn21, and undergoes three first-order phase transitions at [cooling (heating)] 241 (245) K, 297 (328) K, and 389 (406) K. The lowest temperature ferroic phase transition (ferroelastic; mm2→m type) is related to the significant pyroelectric effect. The compound was studied by single-crystal x-ray diffraction at several temperatures, using thermal (differential scanning calorimetry and thermogravimetric analysis) methods and dielectric spectroscopy. The piezoelectric, pyroelectric, and second-harmonic generation (SHG) properties were determined. Density-functional theory calculations in two stable phases are given. The [2,4,6-trimethylpyridinium][BF4] crystal exhibits a SHG efficiency of 1.7 times that of KDP. The mechanism of structural phase transitions in the title compound is discussed.

  6. Structural properties, vibrational spectra and surface-enhanced Raman scattering of 2,4,6-trichloro- and tribromoanilines: A comparative study

    NASA Astrophysics Data System (ADS)

    Haruna, Kabiru; Saleh, Tawfik A.; Al Thagfi, Jameel; Al-Saadi, Abdulaziz A.

    2016-10-01

    A comparative electronic and spectroscopic analysis of 2,4,6-trichloroaniline (TCA) and 2,4,6-tribromoaniline (TBA) was carried out by theoretical and experimental techniques. The NH2 inversion barrier in TCA and TBA molecules was predicted to be three times less than that in aniline and 2,4,6-trifluoroaniline. The size of the halogen substituents in the ortho positions is shown by density functional theory to play an important role in determining the electronic and structural properties of the amino group in the investigated haloaniline derivatives. A thorough interpretation of the infrared and Raman spectra has been performed on the basis of the observed and calculated infrared and Raman spectra as well as calculated potential energy distribution values. In addition, the SERS spectra for both trihaloanilines were successfully collected up to a concentration of 10-6 M using aged hydroxylamine-reduced silver colloid as an active substrate for TCA and TBA. SERS intensities of several peaks were found to linearly change with concentration allowing quantitative analyses of TCA and TBA. A relatively stronger interaction in the case of TBA-silver colloids is predicted compared to the TCA analogue.

  7. Evolution of the Vertebrate Pax4/6 Class of Genes with Focus on Its Novel Member, the Pax10 Gene

    PubMed Central

    Feiner, Nathalie; Meyer, Axel; Kuraku, Shigehiro

    2014-01-01

    The members of the paired box (Pax) family regulate key developmental pathways in many metazoans as tissue-specific transcription factors. Vertebrate genomes typically possess nine Pax genes (Pax1–9), which are derived from four proto-Pax genes in the vertebrate ancestor that were later expanded through the so-called two-round (2R) whole-genome duplication. A recent study proposed that pax6a genes of a subset of teleost fishes (namely, acanthopterygians) are remnants of a paralog generated in the 2R genome duplication, to be renamed pax6.3, and reported one more group of vertebrate Pax genes (Pax6.2), most closely related to the Pax4/6 class. We propose to designate this new member Pax10 instead and reconstruct the evolutionary history of the Pax4/6/10 class with solid phylogenetic evidence. Our synteny analysis showed that Pax4, -6, and -10 originated in the 2R genome duplications early in vertebrate evolution. The phylogenetic analyses of relationships between teleost pax6a and other Pax4, -6, and -10 genes, however, do not support the proposed hypothesis of an ancient origin of the acanthopterygian pax6a genes in the 2R genome duplication. Instead, we confirmed the traditional scenario that the acanthopterygian pax6a is derived from the more recent teleost-specific genome duplication. Notably, Pax6 is present in all vertebrates surveyed to date, whereas Pax4 and -10 were lost multiple times in independent vertebrate lineages, likely because of their restricted expression patterns: Among Pax6-positive domains, Pax10 has retained expression in the adult retina alone, which we documented through in situ hybridization and quantitative reverse transcription polymerase chain reaction experiments on zebrafish, Xenopus, and anole lizard. PMID:24951566

  8. Rietveld refinement, electronic structure and ionic conductivity of Sr4La6(SiO4)6F2 and Sr4La6(SiO4)6O ceramics

    NASA Astrophysics Data System (ADS)

    Boughzala, Khaled; Debbichi, Mourad; Njema, Hela; Bouzouita, Khaled

    2016-07-01

    In this paper, we report the effect of the tunnel anions on the ionic conductivity of Strontium-Lanthanum silicate apatites. The Sr4La6(SiO4)6F2 and Sr4La6(SiO4)6O ceramics were prepared by the solid state reaction method. X-ray diffraction, NMR spectroscopy and Raman measurements were performed to investigate the crystal structure and vibrational active modes. Moreover, the electronic structures of the crystals were evaluated by the first-principles quantum mechanical calculation based on the density functional theory. Finally, the ionic conductivity was studied according to the complex impedance method.

  9. Proteoglycans contain a 4.6 A repeat in muscular dystrophy corneas: x-ray diffraction evidence.

    PubMed Central

    Quantock, A J; Klintworth, G K; Schanzlin, D J; Capel, M S; Lenz, M E; Thonar, E J

    1996-01-01

    Synchrotron x-ray diffraction patterns from macular corneal dystrophy (MCD) corneas contain an unusual reflection that arises because of an undefined ultrastructure with a periodic repeat in the region of 4.6 A. In this study, we compared with wide-angle x-ray diffraction patterns obtained from four normal human corneas and four MCD corneas. Moreover, portions of two of the MCD corneas were pretreated with a specific glycosidase to shed light on the origin of the 4.6 A reflection. None of the normal corneas produced an x-ray reflection in the region of 4.6 A, whereas all four of the MCD corneas did (MCD type I at 4.65 A and 4.63 A, MCD type II at 4.63 A and 4.67 A). This reflection was diminished after incubation of the MCD tissues with either chondroitinase ABC or N-glycanase. The findings indicate that glycosaminoglycans or proteoglycans contribute to the unusual MCD x-ray reflection and hence most likely contain a periodic 4.6 A ultrastructure. Furthermore, the results imply that periodic 4.6 A MCD ultrastructures reside in either intact, unsulfated lumican molecules and regions of the CS/DS-containing molecules or in a region of a hybrid macromolecular aggregate formed by the interaction of the two molecules. PMID:8785355

  10. Protected Graft Copolymer Excipient Leads to a Higher Acute Maximum Tolerated Dose and Extends Residence Time of Vasoactive Intestinal Peptide Significantly Better than Sterically Stabilized Micelles

    PubMed Central

    Reichstetter, Sandra; Castillo, Gerardo M.; Rubinstein, Israel; Nishimoto-Ashfield, Akiko; Lai, ManShun; Jones, Cynthia C.; Banjeree, Aryamitra; Lyubimov, Alex; Bloedow, Duane C.; Bogdanov, Alexei; Bolotin, Elijah M.

    2013-01-01

    Purpose To determine and compare pharmacokinetics and toxicity of two nanoformulations of Vasoactive Intestinal Peptide (VIP). Methods VIP was formulated using a micellar (Sterically Stabilized Micelles, SSM) and a polymer-based (Protected Graft Copolymer, PGC) nanocarrier at various loading percentages. VIP binding to the nanocarriers, pharmacokinetics, blood pressure, blood chemistry, and acute maximum tolerated dose (MTD) of the formulations after injection into BALB/c mice were determined. Results Both formulations significantly extend in vivo residence time compared to unformulated VIP. Formulation toxicity is dependent on loading percentage, showing major differences between the two carrier types. Both formulations increase in vivo potency of unformulated VIP and show acute MTDs at least 140 times lower than unformulated VIP, but still at least 100 times higher than the anticipated highest human dose, 1–5 μg/kg. These nanocarriers prevented a significant drop in arterial blood pressure compared to unformulated VIP. Conclusions While both carriers enhance in vivo residence time compared to unformulated VIP and reduce the drop in blood pressure immediately after injection, PGC is the excipient of choice to extend residence time and improve the safety of potent therapeutic peptides such as VIP. PMID:23224976

  11. Synthesis and microstructure of fluorapatite-type Ca10-2xSmxNax(PO4)6F2 solid solutions for immobilization of trivalent minor actinide

    NASA Astrophysics Data System (ADS)

    Huang, Yi; Zhang, Haibin; Zhou, Xiaosong; Peng, Shuming

    2017-03-01

    Ca10-2xSmxNax(PO4)6F2 (x = 0.8-1.2) solid solutions were successfully synthesized by the solid state reaction method using samarium (Sm) as the surrogate for trivalent minor actinide neptunium (Np). The influences of calcining temperature, holding time and Sm doping content on the phase composition and microstructure of Ca10-2xSmxNax(PO4)6F2 were investigated. The results indicated that the optimized calcining temperature and holding time for preparing Ca10-2xSmxNax(PO4)6F2 were 1000 °C and 2 h. Ca10-2xSmxNax(PO4)6F2 were confirmed to be the discontinuous solid solutions and solid solubility limit of Sm in the Ca10-2xSmxNax(PO4)6F2 was 1.2 formula units. The rod-like grains of Ca10-2xSmxNax(PO4)6F2 had typical hexagonal characteristics with a diameter of 3-5 μm and a length of 10-20 μm. No significant changes on the microstructures of Ca10-2xSmxNax(PO4)6F2 were observed with the increase of Sm doping content. The Ca, Sm, Na, P, O and F elements were nearly distributed uniformly in the Ca8Sm1Na1(PO4)6F2 solid solution.

  12. Synthèse et étude structurale de Na9Cr(MoO4)6.

    PubMed

    Dridi, Wassim; Ennajeh, Ines; Zid, Mohamed Faouzi

    2015-05-01

    The title compound, nona-sodium chromium(III) hexa-kis[molybdate(VI)], Na9Cr(MoO4)6 was prepared by solid-state reactions. The basic structure units are isolated polyhedral clusters composed of a central CrO6 octa-hedron sharing vertices with six MoO4 tetrahedra to form an open framework in which the Na(+) cations are bound to the free vertices of the MoO4 tetra-hedra. The Cr(3+) cation has site symmetry of 32 (6a), one Na atom sits on a twofold axis (18e), and all other atoms are at general positions. The bond-valance-sum model confirms the expected values of ion charges. The title compound is isotypic with Na9Sc(MoO4)6 and Na9Fe(MoO4)6. It is compared and discussed with similar structures.

  13. MEISENHEIMER COMPLEX BETWEEN 2,4,6-TRINITROTOLUENE AND 3-AMINOPROPYLTRIETHOXYSILANE AND ITS USE FOR A PAPER-BASED SENSOR

    PubMed Central

    Hughes, Shantelle; Dasary, Samuel S. R.; Begum, Salma; Williams, Nya; Yu, Hongtao

    2015-01-01

    2,4,6-Trinitrotoluene (TNT) forms a red-colored Meisenheimer complex with 3-aminopropyltrenthoxysilane (APTES) both in solution and on solid phase. The TNT-APTES complex is unique since it forms yellow-colored complexes with 2,4,6-trinitrophenol and 4-nitrophenol, and no complex with 2,4-dinitrotoluene. The absorption spectrum of TNT-APTES has two absorption bands at 530 and 650 nm, while APTES complexes with 2,4,6-trinitrophenol and 4-nitrophenol have absorption maxima at around 420 nm, and no absorption change for 2,4-dinitrotoluene. The TNT-APTES complex facilitates the exchange of the TNT-CH3 proton/deuteron with solvent molecules. The red color of TNT-APTES is immediately visible at 1 µM of TNT. PMID:26380171

  14. Higher-Order Modes of Modulation Instability in Bose-Einstein Condensates with a Time-Dependent Three-Dimensional Parabolic Potential

    NASA Astrophysics Data System (ADS)

    Zong, Feng-De; Yan, Yu-Sheng; Shen, Sen-Ting

    2014-10-01

    By the similarity reduction and Darboux transformation, we derive higher-order modes of three-dimensional Bose-Einstein condensate modulation instability in the nonautonomous Gross-Pitaevskii equation and manipulate them by regulating the time-dependent potential and gain. Firstly, by the similarity reduction, the (3+1)-dimensional nonautonomous Gross-Pitaevskii equation reduces to a (1+1)-dimensional standard nonlinear Schrödinger equation with constant coefficients. Then, considering the Akhmediev breather solution as the first-order modulation instability solution of the higher-order modes of Bose-Einstein condensate modulation instability, we achieve the Nth-order (N = 2, 3, 4, and 5) modulation instability solutions by the Darboux transformation. Finally, we verify the stable higher-order modes of Bose-Einstein condensate modulation instability and manipulate them by direct numerical simulation. The obtained results may raise the possibility of related experiments and potential applications in Bose-Einstein condensates and other related fields.

  15. Derivation of predicted no effect concentrations (PNEC) for 2,4,6-trichlorophenol based on Chinese resident species.

    PubMed

    Jin, Xiaowei; Zha, Jinmiao; Xu, Yiping; Giesy, John P; Richardson, Kristine L; Wang, Zijian

    2012-01-01

    2,4,6-Trichlorophenol (2,4,6-TCP) is a common chemical intermediate and a by-product of water chlorination and combustion processes, and is a priority pollutant of the aquatic environment in many countries. Although information on the toxicity of 2,4,6-TCP is available, there is a lack of information on the predicted no-effect concentration (PNEC) of 2,4,6-TCP, mainly due to the shortage of chronic and site-specific toxicity data. In the present study, acute and sub-chronic toxicity of 2,4,6-TCP on six different resident Chinese aquatic species were determined. PNEC values were calculated and compared by use of two approaches: assessment factor (AF) and species sensitivity distribution (SSD). Values for acute toxicity ranged from 1.1 mg L(-1) (Plagiognathops microlepis) to 42 mg L(-1) (Corbicula fluminea) and the sub-chronic no observed effect concentrations (NOECs) ranged from 0.05 mg L(-1) (Mylopharyngodon piceus) to 2.0 mg L(-1) (C. fluminea). PNECs obtained by the assessment factor approach with acute (AF=1000, 0.001 mg L(-1)) or chronic (AF=10, 0.005 mg L(-1)) toxicity data were one order of magnitude less than those from SSD methods (0.057 mg L(-1)). PNEC values calculated using SSD methods with a 50% certainty for 2,4,6-TCP was less than those obtained by use of the USEPA recommend final chronic value (FCV) method (0.097 mg L(-1)) and the one obtained by use of the USEPA recommend acute-to-chronic (ACR) methods (0.073 mg L(-1)). PNECs derived using AF methods were more protective and conservative than that derived using SSD methods.

  16. Federal Emergency Management Information System (FEMIS) Bill of Materials (BOM) for FEMIS Version 1.4.6

    SciTech Connect

    Homer, B.J., Johnson, D.M.; Wood, B.M.; Stoops, L.R.; Fangman, P.M.; Johnson, R.L.; Loveall, R.M.; Millard, W.D.; Johnson, S.M.; Downing, T.R.

    1999-03-12

    This document describes the hardware and software required for the Federal Emergency Management Information System version 1.4.6 (FEMIS{copyright} v1.4.6). FEMIS is designed for a single Chemical Stockpile Emergency Preparedness Program (CSEPP) site that has multiple Emergency Operations Centers (EOCs). Each EOC has personal computers (PCs) that emergency planners and operations personnel use to do their jobs. These PCs are connected via a local area network (LAN) to servers that provide EOC-wide services. Each EOC is interconnected to other EOCS via a Wide Area Network (WAN).

  17. Bibliographie annotee 4-6--Francais langue seconde-immersion: Selection d'ouvrages de la litterature jeunesse. Supplement 2001 (Annotated Bibliography 4-6--French as a Second Language-Immersion: Selection of Works from Children's Literature. Supplement 2001).

    ERIC Educational Resources Information Center

    Alberta Learning, Edmonton. Direction de l'education francaise.

    The document comprises 42 inserts to be included in the List of Books (4-6) for French as a Second Language (Immersion)--a selection of works of youth literature--published by Alberta Learning in 2000. Thirty-seven of the items appeal to the world of imagination and esthetics, and five items are of an informative nature. An appendix, entitled "How…

  18. Gendered Patterns in High Achievement in Mathematics for Grades 4, 6, and 8

    ERIC Educational Resources Information Center

    Falvey, Laura J.

    2012-01-01

    The issue of underrepresentation of women in science, technology, engineering, and mathematics (STEM) careers is especially important to the future of the United States in current times when STEM careers play an increasingly important role in the global economy (Toulmin & Groome, 2007; United States Department of Labor, 2007). The pool of…

  19. The Greatest Educational Change America Has Ever Seen, 2003: Lesson Plans for Grades 4-6.

    ERIC Educational Resources Information Center

    United States Mint (Dept. of Treasury), Washington, DC.

    The United States Mint 50 State Quarters Program launched a 10-year initiative in 1999, commemorating each of the nation's states in the order they were admitted into the Union. Approximately every 10 weeks (5 times a year) through 2008, a new limited-edition quarter that displays an individual state's design is released into general circulation.…

  20. Shortened time interval between colorectal cancer diagnosis and risk testing for hereditary colorectal cancer is not related to higher psychological distress.

    PubMed

    Landsbergen, K M; Prins, J B; Brunner, H G; Hoogerbrugge, N

    2011-03-01

    Current diagnostic practices have shortened the interval between colorectal cancer (CRC) diagnosis and genetic analysis for Lynch syndrome by MSI-testing. We studied the relation of time between MSI-testing since CRC diagnosis (MSI-CRC interval) and psychological distress. We performed a cross-sectional study in 89 patients who had previously been treated for CRC. Data were collected during MSI-testing after genetic counseling. Psychological distress was measured with the IES, the SCL-90 and the POMS; social issues with the ISS, ISB and the ODHCF. The median time of MSI-CRC interval was 24 months (range 0-332), with 23% of the patients diagnosed less than 12 months and 42% more than 36 months prior to MSI-testing. In 34% of the patients cancer specific distress was high (IES scores >26). Mean psychopathology (SCL-90) scores were low, mean mood states (POMS) scores were moderate. Interval MSI-CRC was not related to psychological distress. High cancer specific distress was reported by 24% of patients diagnosed with CRC less than 12 months ago versus 39 and 35% by those diagnosed between 12 and 36 months and more than 36 months ago respectively. Distress was positively related to female gender (P = 0.04), religiousness (P = 0.01), low social support (P = 0.02) and difficulties with family communication (P < 0.001). Shortened time interval between CRC diagnosis and MSI-testing is not associated with higher psychological distress. Females, religious persons, those having low social support and those reporting difficulties communicating hereditary colorectal cancer with relatives are at higher risk for psychological distress.

  1. Access to 4,6-Diarylpicolinates via a Domino Reaction of Cyclic Sulfamidate Imines with Morita-Baylis-Hillman Acetates of Nitroolefins/Nitrodienes.

    PubMed

    Majee, Debashis; Biswas, Soumen; Mobin, Shaikh M; Samanta, Sampak

    2016-05-20

    An interesting domino reaction of 5-membered cyclic sulfamidate imines with a variety of Morita-Baylis-Hillman acetates of nitroolefins/nitrodienes in the presence of DABCO as an organic base at 55 °C is reported for the first time. This new synthetic strategy provides a series of pharmacologically interesting 4,6-diarylpicolinates in high to excellent yields and allows several compatible functionalities on aryl rings. Moreover, the biologically interesting imidazo[1,2-a]pyridine (alpidem derivative) has been prepared in high chemical yield through a unique procedure.

  2. Regioselective Iron-Catalyzed [2 + 2 + 2] Cycloaddition Reaction Forming 4,6-Disubstituted 2-Aminopyridines from Terminal Alkynes and Cyanamides.

    PubMed

    Spahn, Nathan A; Nguyen, Minh H; Renner, Jonas; Lane, Timothy K; Louie, Janis

    2017-01-06

    Iron complexes bound by redox-active pyridine dialdimine (PDAI) ligands catalyze the cycloaddition of two terminal alkynes and one cyanamide. The reaction is both chemo- and regioselective, as only 4,6-disubstituted 2-aminopyridine products are formed in moderate to high yields. Isolation of an iron azametallacycle (4) suggests that catalyst deactivation occurs with a large excess of cyanamide over longer reaction times. Fe-catalyzed cycloaddition allowed for a straightforward synthesis of a variety of aminopyridines, including known estrogen receptor ligands.

  3. Absorption, tissue distribution, and elimination of residues after 2,4,6-trinitro[14C]toluene administration to sheep

    Technology Transfer Automated Retrieval System (TEKTRAN)

    2,4,6-Trinitrotoluene (TNT) is a persistent contaminant present in high concentrations of some industrial and military sites. Traditional biological bioremediation techniques typically rely on the immobilization of TNT reduction products rather than on TNT mineralization. We hypothesized that sheep ...

  4. Small Schools Reading Curriculum, 4-6: Reading, Language Arts, Mathematics, Science, Social Studies. Scope, Objectives, Activities, Resources, Monitoring Procedures.

    ERIC Educational Resources Information Center

    Hartl, David, Ed.; And Others

    Designed to assist teachers in small schools with the improvement of curriculum and instruction and to help smaller districts which do not have curriculum personnel to comply with Washington's Student Learning Objectives (SLO) Law, this guide contains reading curriculum materials for grades 4-6. The objectives listed are correlated to the Goals…

  5. Tracks the Sand. Jockey's Ridge State Park: An Environmental Education Learning Experience Designed for Grades 4-6.

    ERIC Educational Resources Information Center

    Crutchfield, Fran

    This learning packet, one in a group of eight, was developed by the Jockey's Ridge State Park in North Carolina for Grades 4-6 to learn about animal adaptation and behavior in the dune environment. Loose-leaf pages are presented in 10 sections that contain: (1) introductions to the North Carolina State Park System, the Jockey Ridge State Park, the…

  6. pH-dependent aquatic criteria for 2,4-dichlorophenol, 2,4,6-trichlorophenol and pentachlorophenol.

    PubMed

    Xing, Liqun; Liu, Hongling; Giesy, John P; Yu, Hongxia

    2012-12-15

    Due to their agricultural as well as industrial uses, 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), and pentachlorophenol (PCP) are ubiquitous in the environment and recognized as priority pollutants in many countries. In this study, effects of pH on toxicity to the crustacean Daphnia magna and the alga Scenedesmus obliquus were investigated. Combined published toxicity data of the three chlorophenols along with; relationships between toxicity and pH reported here were used to establish pH-dependent water quality criteria (WQC). The WQC expressed as a function of pH, also considered intra-species variation and proportions of taxonomic groups. At pH 7.8, the recommended acute exposure water quality criteria (WQC) were 286.2 μg 2,4-DCP/l, 341.5 μg 2,4,6-TCP/l and 11.4 μg PCP/l. The recommended chronic exposure WQC were 16.3 μg 2,4-DCP/l, 54.6 μg 2,4,6-TCP/land 3.9 μg PCP/l.

  7. Seeing the "Harm" in "Harmed" and "Harmful": Morphological Processing by Children in Grades 4, 6, and 8

    ERIC Educational Resources Information Center

    Deacon, S. Helene; Campbell, Emily; Tamminga, Meredith; Kirby, John

    2010-01-01

    This study examined morphological processing of inflected and derived words by children in Grades 4, 6, and 8. Participants were shown root forms and inflected, derived, and orthographic control items (e.g., "harm", "harmed", "harmful", or "harmony"), followed by a fragment completion task (e.g., completing "h a_ _"). Participants were equally…

  8. Our Changing Land: Stone Mountain State Park. An Environmental Education Learning Experience Designed for Grades 4-6.

    ERIC Educational Resources Information Center

    Trivette, Larry

    Stone Mountain State Park's environmental education learning experience, Our Changing Land, introduces the student to the geology of the Blue Ridge Mountains, with emphasis on Stone Mountain, through a series of hands-on activities. The learning experience is designed for grades 4-6 and meets curriculum objectives of the standard course of study…

  9. The Effects of Psychomotor Skills Instruction on Attitude toward Singing and General Music among Students in Grades 4-6.

    ERIC Educational Resources Information Center

    Phillips, Kenneth H.; Aitchison, Randall E.

    1998-01-01

    Investigates the relationship of psychomotor skills instruction on student attitudes in grades 4-6 towards singing and general music instruction. Finds females have more positive attitudes, interest declines as grade-level increases, group vocal instruction may produce more positive attitudes, and a positive relationship between liking to sing in…

  10. Testing the Waters. Duke Power State Park: An Environmental Education Learning Experience Designed for Grades 4-6.

    ERIC Educational Resources Information Center

    Rhinehart, William C.; Beazley, Lea J.

    This learning packet, one in a group of eight, was developed by the Duke Power State Park in North Carolina for Grades 4-6 to learn to identify macroinvertebrates found in Lake Norman. Loose-leaf pages are presented in nine sections that contain: (1) introductions to the North Carolina State Park System, the Duke Power State Park, the park's…

  11. Design and Validation of a Photographic Expressive Persian Grammar Test for Children Aged 4-6 Years

    ERIC Educational Resources Information Center

    Haresabadi, Fatemeh; Ebadi, Abbas; Shirazi, Tahereh Sima; Dastjerdi Kazemi, Mehdi

    2016-01-01

    Syntax has a high importance among linguistic parameters, and syntax-related problems are the most common in language disorders. Therefore, the present study aimed to design a Photographic Expressive Persian Grammar Test for Iranian children in the age group of 4-6 years and to determine its validity and reliability. First, the target…

  12. 40 CFR 721.8965 - 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.8965 1H-Pyrole-2, 5-dione, 1-(2,4,6-tribromophenyl)-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as...

  13. Grade 4-6 Student Conceptions and Utilization of Informal and Formal Variable Representations across Mathematically Equivalent Tasks

    ERIC Educational Resources Information Center

    Switzer, Matt

    2011-01-01

    This study reports how 24 grade 4-6 students in one elementary and middle school interpreted formal and informal representations of variables. While interpretations for variables represented as letters (e.g., x and y) have been well established for students in algebra classes and beyond, little research into elementary school students'…

  14. Biosynthesis of gallotannins: formation of polygalloylglucoses by enzymatic acylation of 1,2,3,4,6-penta-O-galloylglucose.

    PubMed

    Hofmann, A S; Gross, G G

    1990-12-01

    Enzyme preparations from leaves of Rhus typhina L. (sumach) catalyzed the galloylation of 1,2,3,4,6-penta-O-galloyl-beta-D-glucopyranose in the presence of the acyl donor beta-glucogallin (1-O-galloyl-beta-D-glucopyranose), yielding a variety of oligomeric gallotannins (hexa- to nonagalloylglucoses) as reaction products.

  15. Leave It to Beaver. Merchants Millpond State Park: An Environmental Education Learning Experience Designed for Grades 4-6.

    ERIC Educational Resources Information Center

    Williams, Floyd K.

    This learning packet, one in a group of eight, was developed by the Merchants Millpond State Park in North Carolina to teach students in grades 4-6 about the habitat and lifestyle of the beaver. Loose-leaf pages are presented in nine sections that contain: (1) introductions to the North Carolina State Parks System, the Merchants Millpond State…

  16. Do Children See the "Danger" in "Dangerous"? Grade 4, 6, and 8 Children's Reading of Morphologically Complex Words

    ERIC Educational Resources Information Center

    Deacon, S. Helene; Whalen, Rachel; Kirby, John R.

    2011-01-01

    We examined whether Grade 4, 6, and 8 children access the base form when reading morphologically complex words. We asked children to read words varying systematically in the frequency of the surface and base forms and in the transparency of the base form. At all grade levels, children were faster at reading derived words with high rather than low…

  17. What Conceptions Have US Grade 4-6 Students' Generalized for Formal and Informal Common Representations of Unknown Addends?

    ERIC Educational Resources Information Center

    Switzer, J. Matt

    2016-01-01

    Research findings have established that students often struggle with mathematical symbols including common misconceptions for literal symbolic representations of variables but provide little evidence of when or how these misconceptions arise. This article reports findings from a study of grade 4-6 students' conception(s) for various…

  18. [2, 4, 6-Trichlorophenol Mineralization Promoted by Anaerobic Reductive Dechlorination of Acclimated Sludge and Extracellular Respiration Dechlorination Pathway].

    PubMed

    Song, Jia-xiu; Li, Ling; Sheng, Fan-fan; Guo, Cui-xiang; Zhang, Yong-ming; Li, Zu-yuan; Wang, Tian-li

    2015-10-01

    In anaerobic conditions, the acclimation of activated sludge was studied with sodium lactate as the electron donor and 2,4,6-trichlorophenol as the electron acceptor. Metabolic characteristics of dechlorination were the focus of this study. The result showed highly efficient dechlorination on 2, 4, 6-trichlorophenol that the conversion rate reached to 100% in 9 - 24 h when initial concentrations of sodium lactate and 2,4, 6-trichlorophenol were 20 mmol x L(-1) and 40 - 80 μmol x L(-1), respectively. The intermediate product 2,4-dichlorophenol was found in low concentration (< 4.22 μmol x L(-1)). And 4-chlorophenol and phenol were the main products. Ortho chlorophenol (2, 4, 6-trichlorophenol, 2, 4-dichlorophenol) can be converted rapidly by acclimated sludge, while the further conversion of 4-chlorophenol and phenol was limited. The residues of anaerobic metabolism were degraded by aerobic sludge, among which 4-chlorophenol (initial concentration of 33 mol x L(-1)) removal rate was up to 100% under aerobic conditions. The acclimated bacteria can rapidly transfer Fe(III) and humus (AQDS) into reductive Fe(II) and AQH2DS which indicated that the dissimilatory iron reducing bacteria was enriched in the acclimated sludge. The electron mediator [Fe(III) and AQDS] significantly accelerated the dechlorination rate. The acclimated sludge could perform extracellular respiration dechlorination with electron mediators.

  19. Strand I - Physical Health; Dental Health for Grades 4-6. Special Edition for Evaluation and Discussion.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Curriculum Development Center.

    This is a curriculum guide for teaching dental health for grades 4-6. Each topic area is outlined under the headings of: (1) reference; (2) major understandings and fundamental concepts; (3) suggested teaching aids and learning activities; and (4) supplementary information for teachers. Main topics include: (1) growth and development of teeth; (2)…

  20. Synthesis and photoluminescence of violet-blue phosphor Ba10(PO4)6F2: Eu2+

    NASA Astrophysics Data System (ADS)

    Huang, Yumei; Zhang, Xinguo; Pan, Jialiang

    2017-01-01

    A violet-blue phosphor of Ba10(PO4)6F2: Eu2+ was prepared by high-temperature solid state reaction. Luminescence, concentration quenching and thermal stability of Ba10(PO4)6F2: Eu2+ are systematically investigated. The phosphor exhibits a broadband UV absorption and a violet-blue emission peaking at 420 nm with corresponding CIE coordinates of (0.163, 0.024). It is found that Eu2+ ions occupy 9-coordinated Ba(1) and 7-coordinated Ba(2) site in Ba10(PO4)6F2, and therefore generate two emission sub-bands at 415 and 433 nm. The optimal concentration of Eu2+ is 5 mol% according to emission intensity and the quenching mechanism is verified to be a dipole-dipole interaction. Ba10(PO4)6F2: 0.05Eu2+ phosphor shows good thermal stability with 81% of room temperature intensity at 180 °C.

  1. Analysis of 2,4,6-nonatrienal geometrical isomers from male flea beetles, Epitrix hirtipennis and E. fuscula

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Geometrical isomers of 2,4,6-nonatrienal have been reported from a variety of food- and insect-related sources. It was discovered recently that the eggplant flea beetle, Epitrix fuscula, uses the (2E,4E,6Z) and (2E,4E,6E) isomers as components of its male-produced aggregation pheromone. Here, we l...

  2. Food recognition and willingness to try fruits and vegetables of rural children in grades 4-6

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to assess and compare food recognition, food experience, self-reported willingness to taste, and actual consumption of fruit and vegetable snacks during the school day. One hundred eighty-six children in grades 4-6 in a rural Mississippi elementary school were asked t...

  3. Aerospace Mechanisms Symposium (22nd) Held at Hampton, Virginia on 4-6 May 1988.

    DTIC Science & Technology

    1988-05-06

    base with redundant reading heads. The Mobile Transporter also has to detect which bay it is on at any time. Various methods of encoding truss... extend from the actuator. As the wax cools and solidifies, it contracts, allowing the rod to be pushed back into the actuator. These commercial...and 2b. This actuator will extend 7.5 cm against a resisting force of 120 N (27 Ibs) when heated from 35 0 C to 40 0 C. 14 Figure 2a: HOP Ac~utcr

  4. Maternal zinc status is associated with breast milk zinc concentration and zinc status in breastfed infants aged 4-6 months.

    PubMed

    Dumrongwongsiri, Oraporn; Suthutvoravut, Umaporn; Chatvutinun, Suthida; Phoonlabdacha, Phanphen; Sangcakul, Areeporn; Siripinyanond, Artitaya; Thiengmanee, Usana; Chongviriyaphan, Nalinee

    2015-01-01

    Breast milk provides adequate nutrients during the first 6 months of life. However, there are some reports of zinc deficiency in breastfed infants. This study was conducted to determine the prevalence of zinc deficiency in infants aged 4-6 months and the associated factors. Healthy infants aged 4-6 months and their mothers were enrolled. They were classified by feeding types as breastfed (BF), formula-fed (FF), and mixed groups (MF). Data collection included demographic data, perinatal data, given diets, and anthropometric measurement. Blood from infants and lactating mothers, and breast milk samples were collected to assess plasma and breast milk zinc concentrations. From 158 infants, the prevalence of zinc deficiency (plasma level below 10.7 mol/L) was 7.6%, and according to feeding groups 14.9%, 5.3%, and 2.9% in the BF, the FF, and the MF groups, respectively. Breastfed infants with zinc deficiency had significantly lower maternal zinc concentrations compared with those without zinc deficiency. There was a higher proportion of maternal zinc deficiency in zinc-deficient infants than those without zinc deficiency (66.7% vs 16.2%, p=0.02). There was a positive correlation between zinc concentrations in breast milk and plasma zinc concentrations of infants (r=0.62, p=0.01) and plasma zinc concentrations of lactating mothers (r=0.56, p=0.016). Using the regression analysis, infant zinc status was associated with maternal plasma zinc concentrations among breastfed infants. The results of this study suggest that breastfed infants aged 4-6 months may have a risk of zinc deficiency and that risk is associated with maternal zinc status and breast milk zinc concentrations.

  5. Higher-order split operator schemes for solving the Schrödinger equation in the time-dependent wave packet method: applications to triatomic reactive scattering calculations.

    PubMed

    Sun, Zhigang; Yang, Weitao; Zhang, Dong H

    2012-02-14

    The efficiency of the numerical propagators for solving the time-dependent Schrödinger equation in the wave packet approach to reactive scattering is of vital importance. In this Perspective, we first briefly review the propagators used in quantum reactive scattering calculations and their applications to triatomic reactions. Then we present a detailed comparison of about thirty higher-order split operator propagators for solving the Schrödinger equation with their applications to the wave packet evolution within a one-dimensional Morse potential, and the total reaction probability calculations for the H + HD, H + NH, H + O(2), and F + HD reactions. These four triatomic reactions have quite different dynamic characteristics and thus provide a comprehensive picture of the relative advantages of these higher-order propagation methods for describing reactive scattering dynamics. Our calculations reveal that the most often used second-order split operator method is typically more efficient for a direct reaction, particularly for those involving flat potential energy surfaces. However, the optimal higher-order split operator methods are more suitable for a reaction with resonances and intermediate complexes or a reaction experiencing potential energy surface with fluctuations of considerable amplitude. Three 4th-order and one 6th-order split operator methods, which are most efficient for solving reactive scattering in various conditions among the tested ones, are recommended for general applications. In addition, a brief discussion on the relative performance between the Chebyshev real wave packet method and the split operator method is given. The results in this Perspective are expected to stimulate more applications of (high-order) split operators to the quantum reactive scattering calculation and other related problems.

  6. Biochronometry; Proceedings of the Symposium, Friday Harbor, Wash., September 4-6, 1969.

    NASA Technical Reports Server (NTRS)

    Menaker, M.

    1971-01-01

    Topics discussed include circadian activity rhythms in birds and man, variation of circadian rhythms in monkeys, resetting of circadian eclosion rhythm in fruitflies, the effectiveness of mathematical models of circadian rhythms, the influence of ac electric fields on circadian rhythms in man, the relation between changes in the metabolic rate and circadian periodicity of the resistance of pocket mice to ionizing radiation, the relation between circadian organization and the photoperiodic time measurement in moths, the circadian rhythm of optic nerve potentials in the isolated eye of the sea hare, phasing of circadian temperature rhythms in the pocket mouse by specific spectral regions, the phase-shifting effect of light on circadian rhymicity in the fruifly, hormonal control of circadian rhythms in the fruitfly, metabolically controlled temperature compensation in the circadian rhythm of algae, and circadian rhythms in the chloroplasts of algae. Individual items are abstracted in this issue.

  7. Rapid restoration of methanogenesis in an acidified UASB reactor treating 2,4,6-trichlorophenol (TCP).

    PubMed

    Díaz-Báez, María Consuelo; Valderrama-Rincon, Juan Daniel

    2017-02-15

    Anaerobic bioreactors are often used for removal of xenobiotic and highly toxic pollutants from wastewater. Most of the time, the pollutant is so toxic that the stability of the reactor becomes compromised. It is well known that methanogens are one of the most sensitive organisms in the anaerobic consortia and hence the stability of the reactors is highly dependant on methanogenesis. Unfortunately few studies have focused on recovering the methanogenic activity once it has been inhibited by highly toxic pollutants. Here we establish a quick recovery strategy for neutralization of an acidified UASB reactor after failure by intoxication with an excess of TCP in the influent. Once the reactor returned to pH values compatible with methanogenesis, biogas production was re-started after one day and the system was re-acclimated to TCP. Successful removal of TCP from synthetic wastewater was shown for concentrations up to 70mg/L after restoration.

  8. Optical techniques for industrial inspection; Proceedings of the Meeting, Quebec, Canada, June 4-6, 1986

    SciTech Connect

    Cielo, P.G.

    1986-01-01

    Papers on optical inspection in industry; hot-slab surface inspection by the laser scanning method; surface inspection based on stochastic modeling; a semiconductor processing technique based on Faraday rotation measurements using a CO/sub 2/ laser; an intelligent vision controller for circuits card lead inspection; and noncontacting optical measurement and inspection systems are presented. Topics discussed include optical sensing techniques for three-dimensional machine vision; the performance analysis of a three-dimensional sensor based on time-of-flight measurements; triangulation with large dynamical range; and recognition for three-dimensional surface shape using multiple distance features. Consideration is given to Raman spectroscopy applied to polymer analysis; an optical approach to the measurement of the lignin content of kraft pulps and of delignification in kraft pulping; diagnostics from imaging inside gas turbine combustors; and environmental-noise analysis in active-vision systems for adaptive welding.

  9. U.S. - Russian Second Space Surveillance Workshop, 4-6 July 1996, Poznan, Poland,

    DTIC Science & Technology

    1996-08-01

    account gravitational field, third column indicates whether static or dynamic model of atmosphere is used, fourth column presents number of...operations CPU-time Precision static 1100 0.0003s 1.5(0.5)km A 6 x 2 model (2200) 0.0006s e < 0.05 F o.7 __ static 2800 0.0006s 0.2(0.1)km AP 8 x 8 model...6300) 0.0015s e < 0.05 F10.7 0.2(0.1)km NAP 8 x 8 dinamic 4200 0.001s e < 0.05, model (12000) 0.003s 3% atmospheric drag e < 0.1 N 6 x 2 dinamic I0c

  10. Adsorption of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) on a soil organic matter. A DFT M05 computational study.

    PubMed

    Sviatenko, Liudmyla K; Gorb, Leonid; Shukla, Manoj K; Seiter, Jennifer M; Leszczynska, Danuta; Leszczynski, Jerzy

    2016-04-01

    Adsorption of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) by soil organic matter considering the Leonardite Humic Acid (LHA) model at the M05/tzvp level of Density Functional Theory (DFT) applying cluster approximation has been investigated. Different orientations of CL-20 toward LHA surface were examined. It was found that deprotonation of LHA is required to obtain stable complexes with CL-20. Hydrogen bonds between CL-20 and deprotonated LHA were analyzed applying the atoms in molecules (AIM) theory. An attachment or removal of an electron with respect to the complex does not have significant effect on mutual orientation of the adsorbent in complexes. It was shown that adsorbed CL-20 does not undergo redox transformation and, therefore, adsorption on soil organic matter may be responsible for decrease of the degradation rate of CL-20 in soil.

  11. The behaviour of incompatible elements during hydrous melting of metasomatized peridotite at 4-6 GPa and 1000 °C-1200 °C

    NASA Astrophysics Data System (ADS)

    Kessel, R.; Fumagalli, P.; Pettke, T.

    2015-11-01

    Trace element behavior during hydrous melting of a metasomatized garnet-peridotite was examined at pressures of 4-6 GPa and temperatures of 1000 °C-1200 °C, conditions appropriate for fluid penetrating the mantle wedge atop the subducting slab. Experiments were performed in a rocking multi-anvil apparatus using a diamond-trap setup. The compositions of the fluid and melt phases were measured using the cryogenic LA-ICP-MS technique. The water-saturated solidus of the K-lherzolite composition is located between 900 °C and 1000 °C at 4 GPa and between 1000 °C and 1100 °C at 5 and 6 GPa. The partition coefficients between fluid or melt and clinopyroxene reveal an asymmetric MREE trough with a minimum at Dy. The clinopyroxene in equilibrium with aqueous fluids is characterized by DUfluid-cpx > DThfluid-cpx while DUmelt-cpx tends to be similar to DThmelt-cpx. The partition coefficients between fluid or melt and garnet reveal very strong light to heavy REE fractionation, DLa/DLu from 95 (hydrous melt) to 1600 (aqueous fluid). The LILE are highly incompatible with partition coefficients > 50. The behavior of HFSE are decoupled, with DZr,Hf close to 1 while DNb,Ta > 10. Garnet is characterized by DUmelt/fluid-garnet < DThmelt/fluid-garnet. A comparison of our experimental partitioning results for trivalent cations as well as the results from the literature and the calculations carried out using the lattice strain model adapted to the presence of water in the bulk system indicates that H2O in the fluid or melt phase has a prominent effect on trace element partitioning. Garnet in mantle rocks in equilibrium with an aqueous fluid is characterized by significantly higher Do(3 +) for REE in the X site of the garnet compared with the partitioning values of the optimal cation in garnet in equilibrium with hydrous melts. Our data show for the first time that the change in the nature of the mobile phase (fluid vs. melt) does affect the affinities of trace elements into the

  12. Kinome-wide RNA interference screen reveals a role for PDK1 in acquired resistance to CDK4/6 inhibition in ER-positive breast cancer.

    PubMed

    Jansen, Valerie M; Bhola, Neil E; Bauer, Joshua A; Formisano, Luigi; Lee, Kyung-Min; Hutchinson, Katherine E; Witkiewicz, Agnieszka K; Moore, Preston D; Estrada, Monica Valeria; Sanchez, Violeta; Ericsson, Paula G; Sanders, Melinda; Pohlmann, Paula R; Pishvaian, Michael J; Riddle, David A; Wei, Wenyi; Dugger, Teresa C; Knudsen, Erik; Arteaga, Carlos L

    2017-03-01

    To discover mechanisms of resistance to CDK4/6 inhibitors, we used a kinome-wide siRNA screen to identify kinases that, when downregulated, promote sensitivity to ribociclib. We identified 3-phosphoinositide dependent protein kinase 1 (PDK1) as the top siRNA that sensitized ER+ MCF-7 cells to ribociclib. Pharmacological inhibition of PDK1 with GSK2334470 in combination with ribociclib or palbociclib, synergistically inhibited proliferation and increased apoptosis in a panel of ER+ breast cancer cell lines. Ribociclib-resistant MCF-7, T47D and HCC1428 cells, selected after chronic drug exposure, displayed increased levels of PDK1, P-RSK2, P-AKT and P-S6 compared to parental drug-sensitive cells. Cell cycle analysis revealed that CDK4/6 inhibition failed to induce G1 arrest, a reduction in S phase, and senescence in ribociclib-resistant cells, suggesting an upregulation of S-phase cyclins/CDKs. The resistant cells exhibited significantly higher levels of P-CDK2, cyclin A, cyclin D1, cyclin E and S477/T479 P-AKT, a CDK2-dependent phosphorylation site within AKT required for full kinase activity and limited to the S-phase of the cell cycle. Treatment with GSK2334470 or the CDK2 inhibitor dinaciclib re-sensitized ribociclib-resistant cells to CDK4/6 inhibitors; however, ribociclib/GSK2334470 inhibited the ribociclib-resistant cells more potently than ribociclib/dinaciclib. Ribociclib/GSK2334470 but not ribociclib/dinaciclib completely abrogated P-Rb, P-S6, P-RSK2, P-CDK2, cyclin A, cyclin D1 and cyclin E expression. Further, ribociclib in combination with GSK2334470 or the PI3Kα inhibitor alpelisib induced regression of MCF-7 xenografts. Finally, primary ER+ tumors displayed increased PDK1, P-S6 and cyclin D1 levels after short treatment with palbociclib. These data support a role for PI3K/PDK1 in mediating acquired resistance to CDK4/6 inhibitors.

  13. Expression of a Drosophila glutathione transferase in Arabidopsis confers the ability to detoxify the environmental pollutant, and explosive, 2,4,6-trinitrotoluene.

    PubMed

    Tzafestas, Kyriakos; Razalan, Maria M; Gyulev, Ivan; Mazari, Aslam M A; Mannervik, Bengt; Rylott, Elizabeth L; Bruce, Neil C

    2017-04-01

    The explosive 2,4,6-trinitrotoluene (TNT) is a significant, global environmental pollutant that is both toxic and recalcitrant to degradation. Given the sheer scale and inaccessible nature of contaminated areas, phytoremediation may be a viable clean-up approach. Here, we have characterized a Drosophila melanogaster glutathione transferase (DmGSTE6) which has activity towards TNT. Recombinantly expressed, purified DmGSTE6 produces predominantly 2-glutathionyl-4,6-dinitrotoluene, and has a 2.5-fold higher Maximal Velocity (Vmax ), and five-fold lower Michaelis Constant (Km ) than previously characterized TNT-active Arabidopsis thaliana (Arabidopsis) GSTs. Expression of DmGSTE6 in Arabidopsis conferred enhanced resistance to TNT, and increased the ability to remove TNT from contaminated soil relative to wild-type plants. Arabidopsis lines overexpressing TNT-active GSTs AtGST-U24 and AtGST-U25 were compromised in biomass production when grown in the absence of TNT. This yield drag was not observed in the DmGSTE6-expressing Arabidopsis lines. We hypothesize that increased levels of endogenous TNT-active GSTs catalyse excessive glutathionylation of endogenous substrates, depleting glutathione pools, an activity that DmGST may lack. In conclusion, DmGSTE6 has activity towards TNT, producing a compound with potential for further biodegradation. Selecting or manipulating plants to confer DmGSTE6-like activity could contribute towards development of phytoremediation strategies to clean up TNT from polluted military sites.

  14. Uptake of 2,4,6-Trinitrotoluene (TNT) by Vetiver grass (Vetiviera ziznoides L.) -- Preliminary results from a hydroponic study

    NASA Astrophysics Data System (ADS)

    Shakya, K. M.; Sarkar, D.; Datta, R.; Makris, K.; Pachanoor, D.

    2006-05-01

    2,4,6-Trinitrotoluene(TNT) is a potent mutagen and a Group C human carcinogen that has been widely used to produce munitions and explosives. As a result, vast areas that have been previously used as military ranges, munition burning and open detonation sites have been heavily contaminated with TNT. Conventional remedial activities in such contaminated sites commonly rely on methods such as incineration, land filling and soil composting. Phytoremediation offers a cost-effective solution, utilizing plants to phytoextract TNT from the contaminated soil. We propose the use of vetiver grass (Vetiveria zizanoides) to remove TNT from such contaminated soils. Vetiver is a fast-growing and adaptive grass, enabling its use in TNT-contaminated sites in a wide variety of soil types and climate. We also hypothesized that TNT removal by vetiver grass will be enhanced by utilizing a chaotropic agent (urea) to alter rhizosphere/root hair chemical environment. The objectives of this preliminary hydroponic study were: i) to investigate the effectiveness of vetiver grass in removing TNT from solution, and ii) to evaluate the use of a common agrochemical (urea) in enhancing TNT removal by vetiver grass. Vetiver plants were grown in a hydroponic system with five different TNT concentrations (0, 5, 10, 25, and 50 mg TNT L-1) and three urea concentrations (0, 0.01 and 0.1%). A plant density of 10 g L-1 and three replicate vessels per treatment were used. Aliquots were collected at several time intervals up to 192 hour, and were analyzed for TNT with HPLC. Results showed that vetiver was able to remove TNT from hydroponic solutions. The overall magnitude and kinetics of TNT removal by vetiver grass was enhanced in the presence of urea. TNT removal kinetics depended on TNT and urea initial concentrations, suggestive of second-order kinetic reactions. Preliminary results are encouraging, but in need for verification using more detailed studies involving TNT-contaminated soils. Ongoing

  15. Cyclic voltammetry: a tool to quantify 2,4,6-trichloroanisole in aqueous samples from cork planks boiling industrial process.

    PubMed

    Peres, António M; Freitas, Patrícia; Dias, Luís G; Sousa, Mara E B C; Castro, Luís M; Veloso, Ana C A

    2013-12-15

    Chloroanisoles, namely 2,4,6-trichloroanisole, are pointed out as the primary responsible of the development of musty off-flavours in bottled wine, due to their migration from cork stoppers, which results in huge economical losses for wine industry. A prevention step is the detection of these compounds in cork planks before stoppers are produced. Mass spectrometry gas chromatography is the reference method used although it is far beyond economical possibilities of the majority of cork stoppers producers. In this work, a portable cyclic voltammetry approach was used to detect 2,4,6-trichloroanisole extracted from natural cork planks to the aqueous phase during the cork boiling industrial treatment process. Analyses were carried out under ambient conditions, in less than 15 min with a low use of solvent and without any sample pre-treatment. The proposed technique had detection (0.31±0.01 ng/L) and quantification (0.95±0.05 ng/L) limits lower than the human threshold detection level. For blank solutions, without 2,4,6-trichloroanisole addition, a concentration in the order of the quantification limit was estimated (1.0±0.2 ng/L), which confirms the satisfactory performance of the proposed methodology. For aqueous samples from the industrial cork planks boiling procedure, intra-day repeatabilities were lower than 3%, respectively. Also, 2,4,6-trichloroanisole contents in the aqueous samples determined by this novel approach were in good agreement with those obtained by GC-MS (correlation coefficient equal to 0.98), confirming the satisfactory accuracy of the proposed methodology. So, since this novel approach is a fast, low-cost, portable and user-friendly method, it can be an alternative and helpful tool for in-situ industrial applications, allowing accurate detection of releasable 2,4,6-trichloroanisole in an earlier phase of cork stoppers production, which may allow implementing more effective cork treatments to reduce or avoid future 2,4,6-trichloroanisole

  16. N-Acetylgalactosamine 4,6-O-sulfate residues mediate binding and activation of heparin cofactor II by porcine mucosal dermatan sulfate.

    PubMed

    Halldórsdóttir, Anna Margrét; Zhang, Lijuan; Tollefsen, Douglas M

    2006-08-01

    Dermatan sulfate (DS) accelerates the inhibition of thrombin by heparin cofactor II (HCII). A hexasaccharide consisting of three l-iduronic acid 2-O-sulfate (IdoA2SO3)-->N-acetyl-D-galactosamine 4-O-sulfate (GalNAc4SO3) subunits was previously isolated from porcine skin DS and shown to bind HCII with high affinity. DS from porcine intestinal mucosa has a much lower content of this disaccharide but activates HCII with potency similar to that of porcine skin DS. Therefore, we sought to characterize oligosaccharides from porcine mucosal DS that interact with HCII. DS was partially depolymerized with chondroitinase ABC, and oligosaccharides containing 2-12 monosaccharide units were isolated. The oligosaccharides were then fractionated by anion-exchange and affinity chromatography on HCII-Sepharose, and the disaccharide compositions of selected fractions were determined. We found that the smallest oligosaccharides able to bind HCII were hexasaccharides. Oligosaccharides 6-12 units long that lacked uronic acid (UA)2SO3 but contained one or two GalNAc4,6SO3 residues bound, and binding was proportional to both oligosaccharide size and number of GalNAc4,6SO3 residues. Intact DS and bound dodecasaccharides contained predominantly IdoA but little D-glucuronic acid. Decasaccharides and dodecasaccharides containing one or two GalNAc4,6SO3 residues stimulated thrombin inhibition by HCII and prolonged the clotting time of normal but not HCII-depleted human plasma. These data support the hypothesis that modification of IdoA-->GalNAc4SO3 subunits in the DS polymer by either 2-O-sulfation of IdoA or 6-O-sulfation of GalNAc can generate molecules with HCII-binding sites and anticoagulant activity.

  17. Design, synthesis, and evaluation of 4,6-diaminonicotinamide derivatives as novel and potent immunomodulators targeting JAK3.

    PubMed

    Nakajima, Yutaka; Aoyama, Naohiro; Takahashi, Fumie; Sasaki, Hiroshi; Hatanaka, Keiko; Moritomo, Ayako; Inami, Masamichi; Ito, Misato; Nakamura, Koji; Nakamori, Fumihiro; Inoue, Takayuki; Shirakami, Shohei

    2016-10-01

    In organ transplantation, T cell-mediated immune responses play a key role in the rejection of allografts. Janus kinase 3 (JAK3) is specifically expressed in hematopoietic cells and associated with regulation of T cell development via interleukin-2 signaling pathway. Here, we designed novel 4,6-diaminonicotinamide derivatives as immunomodulators targeting JAK3 for prevention of transplant rejection. Our optimization of C4- and C6-substituents and docking calculations to JAK3 protein confirmed that the 4,6-diaminonicotinamide scaffold resulted in potent inhibition of JAK3. We also investigated avoidance of human ether-a-go-go related gene (hERG) inhibitory activity. Selected compound 28 in combination with tacrolimus prevented allograft rejection in a rat heterotopic cardiac transplantation model.

  18. Detection of 2,4,6-Trinitrotoluene-Utilizing Anaerobic Bacteria by 15N and 13C Incorporation ▿

    PubMed Central

    Gallagher, Erin M.; Young, Lily Y.; McGuinness, Lora M.; Kerkhof, Lee J.

    2010-01-01

    2,4,6-Trinitrotoluene (15N or 13C labeled) was added to Norfolk Harbor sediments to test whether anaerobic bacteria use TNT for growth. Stable-isotope probing (SIP)-terminal restriction fragment length polymorphism (TRFLP) detected peaks in the [15N]TNT cultures (60, 163, and 168 bp). The 60-bp peak was also present in the [13C]TNT cultures and was related to Lysobacter taiwanensis. PMID:20081008

  19. Time Is Money...and the Enemy of College Completion: Transform American Higher Education to Boost Completion and Reduce Costs. Testimony before the United States House of Representatives Subcommittee on Higher Education and Workforce Training

    ERIC Educational Resources Information Center

    Jones, Stan

    2012-01-01

    This paper presents Stan Jones' testimony before the United States House of Representatives Subcommittee on Higher Education and Workforce Training. In his testimony, he talks about a new American majority of students that is emerging on campuses, especially at community colleges. These students must delicately balance long hours at jobs they must…

  20. High-spin intermediates of the photolysis of 2,4,6-triazido-3-chloro-5-fluoropyridine

    PubMed Central

    Korchagin, Denis V; Neuhaus, Patrik; Sander, Wolfram

    2013-01-01

    Summary In contrast to theoretical expectations, the photolysis of 2,4,6-triazido-3-chloro-5-fluoropyridine in argon at 5 K gives rise to EPR peaks of just two triplet mononitrenes, two quintet dinitrenes, and a septet trinitrene. EPR spectral simulations in combination with DFT calculations show that observable nitrenes can be assigned to triplet 2,4-diazido-3-chloro-5-fluoropyridyl-6-nitrene (D T = 1.026 cm−1, E T = 0), triplet 2,6-diazido-3-chloro-5-fluoropyridyl-4-nitrene (D T = 1.122 cm−1, E T = 0.0018 cm−1), quintet 4-azido-3-chloro-5-fluoropyridyl-2,6-dinitrene (D Q = 0.215 cm−1, E Q = 0.0545 cm−1), quintet 2-azido-3-chloro-5-fluoropyridyl-4,6-dinitrene (D Q = 0.209 cm−1, E Q = 0.039 cm−1) and septet 3-chloro-5-fluoropyridyl-2,4,6-trinitrene (D S = −0.1021 cm−1, E S = −0.0034 cm−1). Preferential photodissociation of the azido groups located in ortho-positions to the fluorine atom of pyridines is associated with strong π-conjugation of these groups with the pyridine ring. On photoexcitation, such azido groups are more efficiently involved in reorganization of the molecular electronic system and more easily adopt geometries of the locally excited predissociation states. PMID:23766785

  1. Assessment of Movement Skill Performance in Preschool Children: Convergent Validity Between MOT 4-6 and M-ABC

    PubMed Central

    Cools, Wouter; De Martelaer, Kristine; Vandaele, Bart; Samaey, Christiane; Andries, Caroline

    2010-01-01

    The purpose was to determine the level of agreement between the Motoriktest für Vier- bis Sechsjährige Kinder [MOT 4-6] and the Movement Assessment Battery for Children [M-ABC]. 48 preschool children participated in the study (Mean age = 5 years, 6 months, SD = 3 months). There was high classification agreement (90%) between both tests. A Kappa correlation coefficient (0.67) provided moderately strong support for convergent validity. Less agreement was shown in identification of motor difficulties (58%). This was reflected by lower correlation coefficients on the fine movement cluster and test item level. The MOT 4-6 showed values within the range of similar movement skill performance assessment protocols. Because of its specific focus it may be of meaningful value to assess movement skill competence in typically developing preschool children (ages 4 to 6). Key points The Motoriktest für Vier- bis Sechsjährige Kinder (MOT 4-6) showed values within the range of similar motor performance tests. Because of its specific focus it may be of great value to assess movement skill competence in typically developing preschool children (ages 4 to 6). Children’s movement skill competence can be expressed as a single composite score. The results from this study also support the use of composite scores that include functional categorization (e.g. locomotion, object control and stability). PMID:24149786

  2. Synthèse et étude structurale de Na9Cr(MoO4)6

    PubMed Central

    Dridi, Wassim; Ennajeh, Ines; Zid, Mohamed Faouzi

    2015-01-01

    The title compound, nona­sodium chromium(III) hexa­kis[molybdate(VI)], Na9Cr(MoO4)6 was prepared by solid-state reactions. The basic structure units are isolated polyhedral clusters composed of a central CrO6 octa­hedron sharing vertices with six MoO4 tetrahedra to form an open framework in which the Na+ cations are bound to the free vertices of the MoO4 tetra­hedra. The Cr3+ cation has site symmetry of 32 (6a), one Na atom sits on a twofold axis (18e), and all other atoms are at general positions. The bond-valance-sum model confirms the expected values of ion charges. The title compound is isotypic with Na9Sc(MoO4)6 and Na9Fe(MoO4)6. It is compared and discussed with similar structures. PMID:25995849

  3. Collective Bargaining in Higher Education: Leadership in Uncertain Times. Proceedings of the Annual Conference of the National Center for the Study of Collective Bargaining in Higher Education and the Professions (19th, New York, New York, March 1991).

    ERIC Educational Resources Information Center

    Gibbons, Joan A., Ed.; Johnson, Beth H., Ed.

    This proceedings document discusses academic leadership in uncertain times, the need for a cooperative model of collective bargaining to provide administration and faculty the flexibility required to respond to changing times, who should bargain for whom and for what, readiness of the next generation to lead, and retirement issues for college…

  4. Divided We Fail: Why It's Time for a Broader, More Inclusive Conversation on the Future of Higher Education. A Final Report on the 2013 National Issues Forums

    ERIC Educational Resources Information Center

    Johnson, Jean

    2014-01-01

    At state and institutional levels, leaders are discussing and enacting policy changes that could shape the future of higher education for decades-especially public higher education. But when citizens talk about the mission of higher education today, their conversations are different from those of policymakers. How do their values and concerns…

  5. Effect of Natural Aging and Cold Working on Microstructures and Mechanical Properties of Al-4.6Cu-0.5Mg-0.5Ag alloy

    NASA Astrophysics Data System (ADS)

    Chen, Yu-Te; Lee, Sheng-Long; Bor, Hui-Yun; Lin, Jing-Chie

    2013-06-01

    This research investigates the effects of natural aging and cold working prior to artificial aging on microstructures and mechanical properties of Al-4.6Cu-0.5Mg-0.5Ag alloy. Mechanical properties relative to microstructure variations were elucidated by the observations of the optical microscope (OM), differential scanning calorimeter (DSC), electrical conductivity meter (pct IACS), and transmission electron microscopy (TEM). The results showed that natural aging treatment has little noticeable benefit on the quantity of precipitation strengthening phases and mechanical properties, but it increases the precipitation strengthening rate at the initial stage of artificial aging. Cold working brings more lattice defects which suppress Al-Cu (GP zone) and Mg-Ag clustering, and therefore the precipitation of Ω phase decreases. Furthermore, more dislocations are formed, leading to precipitate the more heterogeneous nucleation of θ' phase. The above-mentioned precipitation phenomena and strain hardening effect are more obvious with higher degrees of cold working.

  6. Electron loss from 1.4-MeV/u U{sup 4,6,10+} ions colliding with Ne, N{sub 2}, and Ar targets

    SciTech Connect

    DuBois, R.D.; Santos, A.C.F.; Stoehlker, Th.; Bosch, F.; Braeuning-Demian, A.; Gumberidze, A.; Hagmann, S.; Kozhuharov, C.; Mann, R.; Muthig, A. Orsic; Spillmann, U.; Tachenov, S.; Bart, W.; Dahl, L.; Franzke, B.; Glatz, J.; Groening, L.; Richter, S.; Wilms, D.; Ullmann, K.

    2004-09-01

    Absolute, total, single- and multiple-electron-loss cross sections are measured for 1.4-MeV/u U{sup 4,6,10+} ions colliding with neon and argon atoms and nitrogen molecules. It is found that the cross sections all have the same dependence on the number of electrons lost and that multiplying the cross sections by the initial number of electrons in the 6s, 6p, and 5f shells yields good agreement between the different projectiles. By combining the present data with previous measurements made at the same velocity, it is shown that the scaled cross sections slowly decrease in magnitude for incoming charge states between 1 and 10, whereas the cross sections for higher-charge-state ions fall off much more rapidly.

  7. Proceedings of the Annual Precise Time and Time Interval (PTTI) Applications and Planning Meeting (22nd) Held in Vienna, Virginia on 4-6 Dec 1990

    DTIC Science & Technology

    1991-05-01

    smaller than 5 x 10-8 ’C. Materials such as Zerodur ,8 Cer-Vit, 9 and ULE10 are available that have comparable values of thermal coefficients11 but this...these proceedings. 8 Zerodur is a trademark of Schott Giasswork, Inc. 9 Cer-Vit is a trademark of Owens-Illinois, Inc. 42 10 ULE-is a trademark of Coming...are not as much as efficient in terms of signal to noise ratio. Moreover, a light signal can be relayed -back by a mirror or by a retroreflector

  8. [O II] emitters at z ˜ 4.6 in the GOODS field: a homogeneous measure of evolving star formation

    NASA Astrophysics Data System (ADS)

    Bayliss, K. D.; McMahon, R. G.; Venemans, B. P.; Banerji, M.; Lewis, J. R.

    2012-11-01

    We present the results of a high-redshift, z = 4.6, survey of [O II] λ3727 emission line galaxies in the GOODS-S field. The survey uses deep near-infrared data in the NB2090 (λc = 2.095 μm, Δ λ = 0.02 μm) and Ks (λc = 2.146 μm, Δ λ = 0.324 μm) filters taken with the European Southern Observatory instrument, HAWK-I. The images reach an emission line flux limit (5σ) of 3.16 × 10-18 erg s-1 cm -2. At z = 4.6, the survey probes a comoving volume of ˜6680 Mpc3. Three [O II] emission line candidates at z ˜ 4.6 are selected using the Lyman-break criteria. Photometric redshift analysis supports the conclusion that these are genuine [O II] emitters, ruling out a z < 3 solution entirely for one of the candidates. In the analysis presented in this paper, two scenarios are considered: first, all three candidates are genuine [O II] emitters and secondly, only the most likely candidate is a genuine [O II] emitter. We use the line fluxes of these objects to place confidence limits on the star formation rate density (SFRD) in bright (log(L[O ii ])>42.0) [O II] emission line galaxies. Assuming an observed [O II]/Hα line ratio of 0.45 and A(Hα) = 1.0 mag, we report an SFRD of ρdot*(log(L[O ii ])>42.0)=0.058 M yr -1 Mpc -3 in our objects. Using small number statistics, we then place a 50 per cent confidence interval on the global star formation rate of ρdot;*(log(L[O ii ])>42.0)=0.058±0.013 M yr -1 Mpc -3. By combining our results with those from low-z surveys, we compile the first homogeneous set of measurements of the SFRD in bright [O II] emitters from z = 0 to 4.6. From this, we conclude that there was an increase in the SFRD in the brightest [O II] emitters of at least a factor of 2 between z = 4.6 and 1.85.

  9. Photocatalytic oxidation of 2,4,6-trichlorophenol in water using a cocurrent downflow contactor reactor (CDCR).

    PubMed

    Ochuma, Idoko J; Fishwick, Robert P; Wood, Joseph; Winterbottom, J Mike

    2007-06-18

    The heterogeneous photocatalytic oxidation of aqueous solutions of 2,4,6-trichlorophenol (2,4,6-TCP) as a model pollutant in industrial wastewater has been carried out in a pilot scale cocurrent downflow contactor reactor (CDCR). The reactions were carried out in the presence of Ultra-Violet radiation, O(2) and TiO(2) photocatalyst (VP Aeroperl P25/20). The TiO(2) was characterized by Dynamic Vapour Sorption (DVS) technique giving specific surface area and surface energy of 46.06 m(2)g(-1) and 80.12 mJ m(-2), respectively. The CDC reactor was fitted with an internally and vertically mounted 1.0 kW or 2.0 kW UV lamp. The reactions were carried out at 50 degrees C and 1 bar, with the reactor being operated in closed loop recycle mode and suspended photocatalyst being re-circulated. The CDC reactor, a device of very high mass transfer efficiency giving unusually large gas hold-up of approximately 50%, was operated with oxygen mass transfer and dissolution in the zone above the UV lamp (high mass transfer zone) and along and around the UV lamp housing (reaction zone). Under optimized reaction conditions, 100% conversion of 2,4,6-TCP was achieved in 180 min using 15 dm(3) solutions with initial concentration of 120 mg dm(-3). A combination of TiO(2) photocatalyst, UV irradiation and oxidant was observed to give the most rapid photodegradation and photomineralization of the 2,4,6-TCP in comparison with irradiation only. Using the 1 kW or 2 kW UV lamps, conversion of 100 mg dm(-3) of 2,4,6-TCP after 30 min was 62.51% and 90.71%, respectively, with initial reaction rates of 1.33 x 10(-5) and 4.22 x 10(-5) mol min(-1), respectively, and rate constants 0.0046 and 0.29 min(-1), respectively.

  10. Vicarious nucleophilic substitution using 4-amino-1,2,4-triazole, hydroxylamine or O-alkylhydroxylamine to prepare 1,3-diamino-2,4,6-trinitrobenzene or 1,3,5-triamino-2,4,6-trinitrobenzene

    DOEpatents

    Mitchell, A.R.; Pagoria, P.F.; Schmidt, R.D.

    1997-05-27

    The present invention relates to a process to produce 1,3-diamino-2,4,6-trinitrobenzene (DATB) or 1,3,5-triamino-2,4,6,trinitrobenzene (TATB) by: (a) reacting at ambient pressure and a temperature of between about 0 and 50 C for between about 0.1 and 24 hr, a trinitroaromatic compound of the structure shown where X, Y, and Z are each independently selected from the group consisting of -H and -NH{sub 2}, with the proviso that at least 1 or 2 of X, Y, and Z are hydrogen; with an effective amount of 1-amino-1,2,4-triazole, hydroxylamine or O-alkylhydroxamine to produce DATB or TATB; in the presence of a strong base selected from sodium butoxide, potassium butoxide, potassium propoxide, sodium propoxide, sodium ethoxide, potassium ethoxide, sodium methoxide, potassium methoxide, and combinations thereof; in a solvent selected from the group consisting of methanol, ethanol, propanol, butanol, dimethylsulphoxide, N-methylpyrrolidone, hexamethylphosphoramide, dimethylformide, dimethylacetamide and mixtures thereof, provided that when alcohols are present or when hydroxylamine or its O-alkyl derivatives replace ATA primarily DATB is formed; and (b) isolating the DATB or TATB produced. DATB and TATB are important and useful specialty explosives and intermediates for other materials.

  11. Vicarious nucleophilic substitution using 4-amino-1,2,4-triazole, hydroxylamine or O-alkylhydroxylamine to prepare 1,3-diamino-2,4,6-trinitrobenzene or 1,3,5-triamino-2,4,6-trinitrobenzene

    DOEpatents

    Mitchell, Alexander R.; Pagoria, Philip F.; Schmidt, Robert D.

    1997-01-01

    The present invention relates to a process to produce 1,3-diamino-2,4,6-trinitrobenzene (DATB) or 1,3,5-triamino-2,4,6,-trinitrobenzene (TATB) by: (a) reacting at ambient pressure and a temperature of between about 0.degree. and 50.degree. C. for between about 0.1 and 24 hr, a trinitroaromatic compound of structure V: ##STR1## wherein X, Y, and Z are each independently selected from the group consisting of --H and --NH.sub.2, with the proviso that at least 1 or 2 of X, Y, and Z are hydrogen; with an effective amount of 1-amino-1,2,4-triazole, hydroxylamine or O-alkylhydroxamine to produce DATB or TATB; in the presence of a strong base selected from sodium butoxide, potassium butoxide, potassium propoxide, sodium propoxide, sodium ethoxide, potassium ethoxide, sodium methoxide, potassium methoxide, and combinations thereof; in a solvent selected from the group consisting of methanol, ethanol, propanol, butanol, dimethylsulphoxide, N-methylpyrrolidone, hexamethylphosphoramide, dimethylformide, dimethylacetamide and mixtures thereof, provided that when alcohols are present or when hydroxylamine or its O-alkyl derivatives replace ATA primarily DATB is formed; and (b) isolating the DATB or TATB produced. DATB and TATB are important and useful specialty explosives and intermediates for other materials.

  12. Glycosylamines of 4,6-O-butylidene-alpha-D-glucopyranose: synthesis and characterization of glycosylamines, and the crystal structure of 4,6-O-butylidene-N-(o-chlorophenyl)-beta-D-glucopyranosylamine.

    PubMed

    Rajsekhar, Gudneppanavar; Rao, Chebrolu P; Saarenketo, Pauli K; Kolehmainen, Erkki; Rissanen, Kari

    2002-02-11

    A total of nine glycosylamines of 4,6-O-butylidene-alpha-D-glucopyranose were synthesized using primary amines having various groups in their ortho- or para-positions. Among these, six are monoglycosylamines, including one primary glycosylamine, and three are bis-glycosylamines. All these compounds were characterized by 1H, 1H-1H COSY, 1H-13C COSY and 13C NMR spectroscopy and FTIR spectra. The FAB mass spectra provided the molecular weights of the products by exhibiting the corresponding molecular ion peaks. The crystal structure of 4,6-O-butylidene-N-(o-chlorophenyl)-beta-D-glucopyranosylamine revealed the C-1 glycosylation, the beta-anomeric nature, and the 4C1 chair conformation of the saccharide unit in the product. In the lattice two types of dimers exist. While one type of dimer is formed through O-H...O type of interactions, the other type is formed via C-H...O type of interactions. In the direction of these C-H...O type of interactions, the dimeric units are connected to form a chain.

  13. Higher specificity of nucleic acid sequence-based amplification isothermal technology than of real-time PCR for quantification of HIV-1 RNA on dried blood spots.

    PubMed

    Mercier-Delarue, Severine; Vray, Muriel; Plantier, Jean Christophe; Maillard, Theodora; Adjout, Zidan; de Olivera, Fabienne; Schnepf, Nathalie; Maylin, Sarah; Simon, Francois; Delaugerre, Constance

    2014-01-01

    Dried blood spots (DBS) are widely proposed as a plasma surrogate for monitoring antiretroviral treatment efficacy based on the HIV-1 RNA level (viral load [VL]) in resource-limited settings. Interfering coamplification of cell-associated HIV-1 DNA during reverse transcription (RT)-PCR can be avoided by using nucleic acid sequence-based amplification (NASBA) technology, which is based on an RNA template and isothermic conditions. We analyzed VL values obtained with DBS and plasma samples by comparing isothermic NASBA (NucliSENS EasyQ HIV-1 V2.0; bioMérieux) with real-time RT-PCR (Cobas TaqMan HIV-1 V2.0; Roche). Samples from 197 HIV-1-infected patients were tested (non-B subtypes in 51% of the cases). Nucleic acid extractions were performed by use of NucliSENS EasyMAG (bioMérieux) and Cobas AmpliPrep (Roche) before the NASBA and RT-PCR quantifications, respectively. Both quantification assays have lower limits of detection of 20 (1.3) and 800 (2.9) log10 copies/ml (log) in plasma and DBS, respectively. The mean (DBS minus plasma) differences were -0.39 and -0.46 log, respectively, for RT-PCR and NASBA. RT-PCR on DBS identified virological failure in 122 of 126 patients (sensitivity, 97%) and viral suppression in 58 of 70 patients (specificity, 83%), yielding 12 false-positive results (median, 3.2 log). NASBA on DBS identified virological failure in 85 of 96 patients (sensitivity, 89%) and viral suppression in 95 of 97 patients (specificity, 98%) and yielded 2 false-positive results (3.0 log for both). Both technologies detected HIV-1 RNA in DBS at a threshold of 800 copies/ml. This higher specificity of NASBA technology could avoid overestimation of poor compliance or the emergence of resistance when monitoring antiretroviral efficacy with the DBS method.

  14. Synthesis, crystal structures and characterization of four coordination polymers based on 5-amino-2,4,6-triiodoisophthalic acid

    SciTech Connect

    Zhang Koulin; Chang Yan; Zhang Jingbo; Yuan Limin; Deng Ye; Diao Guowang; Ng, Seik Weng

    2011-05-15

    One homochiral 1D coordination polymer [Cu(ATIBDC)(2,2'-bipy)].3H{sub 2}O.CH{sub 3}OH (1) and three achiral 1D coordination polymers: [Cd(ATIBDC)(2,2'-bipy)(H{sub 2}O)].3H{sub 2}O (2), [Cd(ATIBDC)(phen)(H{sub 2}O)].4H{sub 2}O (3), and [Mn(ATIBDC)(phen){sub 2}].5H{sub 2}O (4) have been synthesized and characterized (H{sub 2}ATIBDC=5-amino-2,4,6-triiodoisophthalic acid, 2,2'-bipy=2,2'-bipyridine, and phen=1,10-phenanthroline). Extended high dimensional network architectures are further constructed with the help of weak secondary interactions, such as hydrogen bonding, aromatic stacking, and halogen bonding (C-I..{pi} and C-I...N/O). Complex 1 crystallizes in the monoclinic system with chiral space group P2(1) and exhibits a right-handed 2{sub 1} helical chain structure. The homochirality of 1 was confirmed by CD spectrum. Interestingly, two new configurations of decameric water cluster are found in 3 and 4. The acyclic tetrameric cluster (H{sub 2}O){sub 3}(CH{sub 3}OH) in 1 and (H{sub 2}O){sub 4} in 2 array into highly ordered helical infinite chains. Thermal stabilities of all the complexes have been studied. Solid state fluorescent properties of the Cd(II) complexes have been explored. -- Graphical abstract: The synthesis, crystal structures and characterization of one 1D homochiral coordination polymer and three achiral 1D coordination polymers with 5-amino-2,4,6-triiodoisophthalic acid (H{sub 2}ATIBDC) are reported. Display Omitted highlights: > Four 1D coordination polymers with 5-amino-2,4,6-triiodoisophthalate are reported. > The halogen bonds play important roles in the supramolecular assembly. > Solid state fluorescent properties of the Cd(II) complexes are explored.

  15. The role of bone morphogenetic proteins 2, 4, 6 and 7 during ovarian follicular development in sheep: contrast to rat.

    PubMed

    Juengel, Jennifer L; Reader, Karen L; Bibby, Adrian H; Lun, Stan; Ross, Ian; Haydon, Lisa J; McNatty, Kenneth P

    2006-03-01

    The intraovarian roles of BMP family members such as BMP2, 4, 6 and 7 are not well understood, particularly in species with low ovulation rates such as sheep. Therefore, the objectives of these experiments were to determine the expression patterns of mRNAs encoding BMP2, 4, 6 and 7 during ovarian follicular development in sheep, and to determine the effects of these growth factors on ovine granulosa cell functions in vitro. For comparative purposes, the effects of these BMPs were also determined in rat granulosa cells since these factors have been most widely studied in this poly-ovulatory species. As assessed by in situ hybridization, non-atretic ovine follicles expressed mRNA for BMP6 but not 2, 4 or 7. Furthermore, expression of BMP6 was limited to the oocyte of primordial as well as primary, pre-antral and antral follicles. Reverse transcription-PCR of granulosa cell mRNA detected low levels of all the BMPs in some pools of cells. BMP2, 4, 6 and 7 each inhibited progesterone production from ovine granulosa cells without affecting cellular proliferation/survival. Similarly, these BMPs inhibited progesterone production from rat granulosa cells. However, they also stimulated cellular proliferation/survival of the rat granulosa cells highlighting a species-specific difference for these growth factors. In conclusion, in sheep, BMP2, 4, 6 and 7 inhibit granulosa cell differentiation without affecting proliferation. However, as BMP2, 4 and 7 were not detectable by in situ hybridization in any cells of non-atretic ovarian follicles, it seems unlikely that these proteins would have an important intra-ovarian role in regulating follicular development in sheep. In contrast, localization of BMP6 mRNA in the oocyte suggests that this BMP family member may have a paracrine and/or autocrine role in regulating follicular growth in sheep, as has been shown for two other oocyte derived from members of the transforming growth factor superfamily, BMP15 and growth differentiation

  16. Extraction-spectrophotometric determination of boron with 4,6-Di-tert-butyl-3-methoxycatechol and ethyl violet.

    PubMed

    Oshima, M; Shibata, K; Gyouten, T; Motomizu, S; Tôei, K

    1988-05-01

    4,6-Di-tert-butyl-3-methoxycatechol (DBMC) has been developed as a new reagent for boron, the complex anion formed being extracted as an ion-associate with Ethyl Violet into toluene, and the absorbance measured at 610 nm. The calibration graph is linear up to 0.43 mug of boron, the molar absorptivity is 1.02 x 10(5) 1.mole(-1).cm(-1) and the relative standard deviation 1.2%. The method has been applied to the determination of boron in sea-water and river water with satisfactory results.

  17. Buckling tests of three 4.6 meter diameter aluminum honeycomb sandwich conical shells loaded under external pressure

    NASA Technical Reports Server (NTRS)

    Anderson, J. K.; Davis, R. C.

    1975-01-01

    Three aluminum honeycomb sandwich conical shells with a 120 apex angle and a 4.6-m (15.0-ft) base diameter were loaded to failure by a uniform external pressure. The cones differed from one another only in the thickness of their respective face sheets. Test specimen details, test procedure, and test results are discussed. Both buckling and prebuckling data are compared with appropriate theoretical predictions, and good agreement was obtained between test and theory. Extensive imperfection measurements were made and reported on the three cones in the as fabricated condition.

  18. Buckling tests of two 4.6-meter-diameter, magnesium ring-stiffened conical shells loaded under external pressure

    NASA Technical Reports Server (NTRS)

    Anderson, J. K.; DAVIS R. C.

    1973-01-01

    Two ring-stiffened magnesium conical shells with a 120 deg apex angle and a 4.6-meter diameter were loaded to failure by a uniform external pressure. The cones differed from one another only in the number of internal stiffening rings. Test specimen details, test procedure, and test results are discussed. Both buckling and prebuckling data are compared with appropriate theoretical predictions. Measured strains in skin and rings agreed well with theoretical predictions. Extensive imperfection measurements were made and reported on both cones in the as fabricated condition.

  19. High-power phase-locked quantum cascade laser array emitting at λ ˜ 4.6 μm

    NASA Astrophysics Data System (ADS)

    Yan, Fang-Liang; Zhang, Jin-Chuan; Jia, Zhi-Wei; Zhuo, Ning; Zhai, Shen-Qiang; Liu, Shu-Man; Liu, Feng-Qi; Wang, Zhan-Guo

    2016-03-01

    A phase-locked quantum cascade laser (QCL) array consisting of one hundred elements that were integrated in parallel was achieved at λ ˜ 4.6 μm. The proposed Fraunhofer's multiple slits diffraction model predicted and explained the far-field pattern of the phase-locked laser array. A single-lobed far-field pattern, attributed to the emission of an in-phase-like supermode, is obtained near the threshold (Ith). Even at 1.5 Ith, greater than 73.3% of the laser output power is concentrated in a low-divergence beam with an optical power of up to 40 W.

  20. Raman and infrared spectroscopic study of synthetic ungemachite, K3Na8Fe(SO4)6(NO3)2·6H2O

    NASA Astrophysics Data System (ADS)

    Vargas Jentzsch, Paul; Ciobotă, Valerian; Bolanz, Ralph Michael; Kampe, Bernd; Rösch, Petra; Majzlan, Juraj; Popp, Jürgen

    2012-08-01

    Iron is an important element usually found in atmospheric particulate matter, and its occurrence can be attributed to both natural and anthropogenic sources. It is an accepted fact that the atmospheric particles interact with water and other atmospheric components, therefore dissolution-crystallization processes can be expected. In this work, considering specially that low pH values are characteristic of aerosol solutions, we postulate that the rare mineral ungemachite, K3Na8Fe(SO4)6(NO3)2·6H2O can crystallize in atmosphere. The Raman and infrared spectra of synthetic ungemachite are presented and the band assignments are proposed and discussed. This is the first time that a synthetic method for ungemachite is reported.

  1. Hydration with mercuric acetate and the reduction with 9-BBN-H of 2-(1-alkenyl)-4,6-dimethyl-s-triazines.

    PubMed

    Nyquist, H LeRoy; Beeloo, Edward A; Hurlbut, Lydia S; Watson-Clark, Rachel; Harwell, David E

    2002-05-17

    Oxymercuration-demercuration of a double bond in conjugation with the 4,6-dimethyl-s-triazin-2-yl substituent as in alkenes 1a,b gave anti-Markovnikov regioselectivity, which is explained by the electron-withdrawing nature of the triazinyl substituent. However, hydroboration of the conjugated alkenes with 9-BBN-H gave the corresponding alkanes 5a-c under normal workup conditions with or without oxidation. With time and without workup the hydroboration of 1b gave spectral evidence for the formation of intermediates 9-13 resulting from the migration of the 9-BBN moiety from the alpha-carbon to a ring nitrogen with concurrent formation of an exocyclic double bond to an alpha-carbon of the ring. Hydrolysis of the intermediates gave 5a-c. A possible mechanism involving successive allylic rearrangements is presented.

  2. Decomposition of some polynitro arenes initiated by heat and shock Part II: Several N-(2,4,6-trinitrophenyl)-substituted amino derivatives.

    PubMed

    Varga, Róbert; Zeman, Svatopluk; Kouba, Martin

    2006-10-11

    Samples of 2,4,6-trinitroaniline (PAM), 2,4,6-trinitro-N-(2,4,6-trinitrophenyl)aniline (DPA), N,N'-bis(2,4,6-trinitrophenyl)-3,5-dinitropyridine-2,6-diamine (PYX) and N,N',N''-tris(2,4,6-trinitrophenyl)-1,3,5-triazine-2,4,6-triamine (TPM) were exposed to heat or to shock and then analysed chromatographically (LC-UV and LC/MS). It was found that the main identified decomposition products of these two incomplete initiations are identical for each of the compounds studied. It has been stated that the chemical micro-mechanism of the primary fragmentations of their low-temperature decomposition should be the same as in the case of their initiation by shock, including fragmentation during their detonation transformation.

  3. Sediment-mediated reduction of 2,4,6-trinitrotoluene and fate of the resulting aromatic (poly)amines

    SciTech Connect

    Elovitz, M.S. ); Weber, E.J. )

    1999-08-01

    2,4,6-Trinitrotoluene is a major surface and subsurface contaminant found at numerous munitions production and storage facilities. The reductive transformation of 2,4,6-trinitrotoluene (TNT) to aromatic (poly)amines and the consequent fate of these products were studied in anaerobic and aerobic sediment-water systems. Reduction of TNT was rapid under both anaerobic and aerobic conditions. Nitro-reduction was regioselective, leading to the preferential formation of 4-amino-2,6 dinitrotoluene (4-ADNT) and 2,4-diamino-6 nitrotoluene (2,4-DANT). Subsequent sorption of 2,4-DANT was rapid under aerobic conditions and resulted in nearly complete, irreversible retention by the sediment phase. Under anaerobic conditions, the rapidly formed 2,4-DANT displayed little affinity for the sediment phase. Instead, 2,4 DANT was further transformed to products that remained in the aqueous phase. Sorption studies in nontransforming sediments indicated increased irreversible sorption with replacement of nitro groups with amino groups. Covalent binding of the DANTs was partially inhibited under anoxic conditions, but sorption of TNT and the ADNTs was unaffected by changes in redox conditions.

  4. Electrochemical destruction of dinitrotoluene isomers and 2,4,6-trinitrotoluene in spent acid from toluene nitration process.

    PubMed

    Chen, Wen-Shing; Liang, Jing-Song

    2009-01-30

    Mineralization of dinitrotoluene (DNT) isomers and 2,4,6-trinitrotoluene (TNT) in spent acid was conducted by in situ electrogenerated hydrogen peroxide. The electrolytic experiments were carried out to elucidate the influence of various operating parameters on the performance of mineralization of total organic compounds (TOC) in spent acid, including electrode potential, reaction temperature, oxygen dosage and concentration of sulfuric acid. It is worth noting that organic compounds could be completely mineralized by hydrogen peroxide obtained from cathodic reduction of oxygen, which was mainly supplied by anodic oxidation of water. Based on the spectra identified by gas chromatograph/mass spectrometer (GC/MS), it is proposed that oxidative degradation of 2,4-DNT and/or 2,6-DNT, 2,4,6-TNT results in o-mononitrotoluene (MNT) and 1,3,5-trinitrobenzene, respectively. Due to the removal of TOC and some amount of water, the electrolytic method established is promising for industrial application to regeneration of spent acid from toluene nitration process.

  5. Antibacterial Activity of 2-(2′,4′-Dibromophenoxy)-4,6-dibromophenol from Dysidea granulosa

    PubMed Central

    Shridhar, Divya M. P.; Mahajan, Girish B.; Kamat, Vijayendra P.; Naik, Chandrakant G.; Parab, Rajashri R.; Thakur, Nidhi R.; Mishra, Prabhu D.

    2009-01-01

    2-(2′,4′-Dibromophenoxy)-4,6-dibromophenol isolated from the marine sponge Dysidea granulosa (Bergquist) collected off the coast of Lakshadweep islands, Indian Ocean, exhibited potent and broad spectrum in-vitro antibacterial activity, especially against methicillin resistant Staphylococcus aureus (MRSA), methicillin sensitive Staphylococcus aureus (MSSA), vancomycin resistant Enterococci (VRE), vancomycin sensitive Enterococci (VSE) and Bacillus spp. Minimal inhibitory concentration (MIC) was evaluated against 57 clinical and standard strains of Gram positive and Gram negative bacteria. The observed MIC range was 0.117–2.5 μg/mL against all the Gram positive bacteria and 0.5–2 μg/mL against Gram negative bacteria. The in-vitro antibacterial activity observed was better than that of the standard antibiotic linezolid, a marketed anti-MRSA drug. The results establish 2-(2′,4′-dibromophenoxy)-4,6-dibromophenol, as a potential lead molecule for anti-MRSA and anti-VRE drug development. PMID:19841726

  6. Identification of the pI 4.6 extensin peroxidase from Lycopersicon esculentum using proteomics and reverse-genomics.

    PubMed

    Dong, Wen; Kieliszewski, Marcia; Held, Michael A

    2015-04-01

    The regulation of plant cell growth and early defense response involves the insolubilization of hydroxyproline-rich glycoproteins (HRGPs), such as extensin, in the primary cell wall. In tomato (Lycopersicon esculentum), insolubilization occurs by the formation of tyrosyl-crosslinks catalyzed specifically by the pI 4.6 extensin peroxidase (EP). To date, neither the gene encoding EP nor the protein itself has been identified. Here, we have identified tomato EP candidates using both proteomic and bioinformatic approaches. Bioinformatic screening of the tomato genome yielded eight EP candidates, which contained a putative signal sequence and a predicted pI near 4.6. Biochemical fractionation of tomato culture media followed by proteomic detection further refined our list of EP candidates to three, with the lead candidate designated (CG5). To test for EP crosslinking activity, we cloned into a bacterial expression vector the CG5 open-reading frame from tomato cDNA. The CG5 was expressed in Escherichia coli, fractionated from inclusion bodies, and folded in vitro. The peroxidase activity of CG5 was assayed and quantified by ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)) assay. Subsequent extensin crosslinking assays showed that CG5 can covalently crosslink authentic tomato P1 extensin and P3-type extensin analogs in vitro supporting our hypothesis that CG5 encodes a tomato EP.

  7. CDK4/6 or MAPK blockade enhances efficacy of EGFR inhibition in oesophageal squamous cell carcinoma

    PubMed Central

    Zhou, Jin; Wu, Zhong; Wong, Gabrielle; Pectasides, Eirini; Nagaraja, Ankur; Stachler, Matthew; Zhang, Haikuo; Chen, Ting; Zhang, Haisheng; Liu, Jie Bin; Xu, Xinsen; Sicinska, Ewa; Sanchez-Vega, Francisco; Rustgi, Anil K.; Diehl, J. Alan; Wong, Kwok-Kin; Bass, Adam J.

    2017-01-01

    Oesophageal squamous cell carcinoma is a deadly disease where systemic therapy has relied upon empiric chemotherapy despite the presence of genomic alterations pointing to candidate therapeutic targets, including recurrent amplification of the gene encoding receptor tyrosine kinase epidermal growth factor receptor (EGFR). Here, we demonstrate that EGFR-targeting small-molecule inhibitors have efficacy in EGFR-amplified oesophageal squamous cell carcinoma (ESCC), but may become quickly ineffective. Resistance can occur following the emergence of epithelial–mesenchymal transition and by reactivation of the mitogen-activated protein kinase (MAPK) pathway following EGFR blockade. We demonstrate that blockade of this rebound activation with MEK (mitogen-activated protein kinase kinase) inhibition enhances EGFR inhibitor-induced apoptosis and cell cycle arrest, and delays resistance to EGFR monotherapy. Furthermore, genomic profiling shows that cell cycle regulators are altered in the majority of EGFR-amplified tumours and a combination of cyclin-dependent kinase 4/6 (CDK4/6) and EGFR inhibitors prevents the emergence of resistance in vitro and in vivo. These data suggest that upfront combination strategies targeting EGFR amplification, guided by adaptive pathway reactivation or by co-occurring genomic alterations, should be tested clinically. PMID:28059068

  8. Theoretical study of the structures and first hyperpolarizabilities of C60Cl n and Li@C60Cl n (n = 4, 6, 8, 10).

    PubMed

    Song, Yao-Dong; Wang, Liang; Wu, Li-Ming

    2016-06-01

    We recently reported (Song Y-D et al., 2016, J Mol Model 22:50) that doping with Li greatly affects the static first hyperpolarizability of C60Cl2. In this work, with a view to creating nonlinear optical materials with high thermodynamic stability and wide transparent regions, a series of Li@C60Cl n (n = 4, 6, 8, 10) were designed. The structures, electrostatic potentials, electronic structures, absorption spectra, and linear and nonlinear optical properties of C60Cl n and Li@C60Cl n were systematically investigated using density functional theory (DFT) methods. The results of our calculations indicated that the stability of these molecules decreases in the order Li@C60Cl10 > Li@C60Cl8 > Li@C60Cl6 > Li@C60Cl4. It is clear that the number of Cl atoms greatly influences the stability of Li@C60Cl n . Li@C60Cl n showed greater thermodynamic stability than Li@C60Cl2. We also investigated the first hyperpolarizabilities of Li@C60Cl n and found them to be 2973, 3640, 4307, and 2627 au for n = 4, 6, 8, and 10, respectively-higher than that of Li@C60Cl2. Finally, we noted that the transparent region could be modulated by increasing the number of Cl atoms: Li@C60Cl n possess wider transparent regions than that of Li@C60Cl2. We therefore believe that this study has highlighted an effective method for designing nonlinear optical materials with high thermodynamic stability and wide transparent regions.

  9. Higher Education.

    ERIC Educational Resources Information Center

    Hendrickson, Robert M.; Gregory, Dennis E.

    Decisions made by federal and state courts during 1983 concerning higher education are reported in this chapter. Issues of employment and the treatment of students underlay the bulk of the litigation. Specific topics addressed in these and other cases included federal authority to enforce regulations against age discrimination and to revoke an…

  10. Higher Education.

    ERIC Educational Resources Information Center

    Hendrickson, Robert M.

    Litigation in 1987 was very brisk with an increase in the number of higher education cases reviewed. Cases discussed in this chapter are organized under four major topics: (1) intergovernmental relations; (2) employees, involving discrimination claims, tenured and nontenured faculty, collective bargaining and denial of employee benefits; (3)…

  11. Higher Education.

    ERIC Educational Resources Information Center

    Hendrickson, Robert M.; Finnegan, Dorothy E.

    The higher education case law in 1988 is extensive. Cases discussed in this chapter are organized under five major topics: (1) intergovernmental relations; (2) employees, involving discrimination claims, tenured and nontenured faculty, collective bargaining, and denial of employee benefits; (3) students, involving admissions, financial aid, First…

  12. Higher Education.

    ERIC Educational Resources Information Center

    Knowles, Laurence W.; Wedlock, Eldon D., Jr.

    Courts have been consistently reluctant to interfere with governing boards' powers to control the administration of institutions of higher education. This deference seems to be based on the belief that board expertise makes it significantly more qualified than are the courts to make the necessary administrative decisions. Uncritical deference by…

  13. Poly[[penta­aqua­(μ4-pyridine-2,4,6-tri­carboxyl­ato)(μ3-pyridine-2,4,6-tri­carboxyl­ato)diterbium(III)] mono­hydrate

    PubMed Central

    Yu, Xiao-Ke; Zhu, Hong-Lin

    2012-01-01

    The three-dimensional title coordination polymer, {[Tb2(C8H2NO6)2(H2O)5]·H2O}n, was hydro­thermally synthesized by reacting the corresponding rare-earth salt with pyridine-2,4,6-tricarb­oxy­lic acid (H3ptc). There are two independent TbIII atoms in the structure, one of which is nine-coordinated, forming a monocapped NO8 square-anti­prism and the other is eight-coordinated exhibiting a 4,4-bicapped NO7 trigonal–prismatic environment. The complex units are inter­connected through the ptc3− anions acting in different coordination modes, resulting in a three-dimensional coordin­ation polymer. The crystal structure features extensive O—H⋯O hydrogen bonds. PMID:22904780

  14. Microwave-promoted and Lewis acid catalysed synthesis of steroidal A- and D-ring fused 4,6-diarylpyridines.

    PubMed

    Dutta, Mandakini; Saikia, Pallabi; Gogoi, Sanjib; Boruah, Romesh C

    2013-04-01

    The preparation of novel steroidal heterocycles containing 4,6-diaryl substituted pyridine moiety fused to the 2,3- and 16,17-positions of the steroid nucleus is described. The Michael reaction of steroidal ketones (1a, 1b and 1c) with in situ generated chalcones provided the intermediates 3,5-diaryl-1,5-dicarbonyl steroidal derivatives (4a-s). Subsequently, the intermediates 4a-s were converted to the pyridine derivatives (5a-s) by solid phase reaction with urea in presence of BF3.OEt2 as the catalyst under microwave irradiation. All the synthesized heterosteroids are new compounds and are currently being evaluated for their biological activities.

  15. L shell x ray production in high-Z elements using 4-6 MeV/u fluorine ions

    NASA Astrophysics Data System (ADS)

    Kumar, Sunil; Singh, Udai; Oswal, M.; Singh, G.; Singh, N.; Mehta, D.; Nandi, T.; Lapicki, G.

    2017-03-01

    L shell line and total x ray production cross sections in 78Pt, 79Au, 82Pb, 83Bi, 90Th, and 92U targets ionized by 4-6 MeV/u fluorine ions were measured. These cross sections are compared with available theories for L shell ionization using single- and multiple-hole fluorescence and the Coster-Kronig yields. The ECPSSR and the ECUSAR theories exhibit good agreement with the measured data, whereas, the FBA theory overestimates them by a factor of two. Although for the F ion charge states q = 6-8 the multiple-hole atomic parameters do not significantly differ from the single-hole values, after an account for the multiple-holes, our data are better in agreement with the ECUSAR than the ECPSSR theory.

  16. High-Pressure Far- and Mid-Infrared Study of 1,3,5-Triamino-2,4,6-trinitrobenzene

    SciTech Connect

    Pravica, M.; Yulga, B; Tkachev, S; Liu, Z

    2009-01-01

    Synchrotron infrared measurements of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) have been performed in the far-IR and mid-IR spectral regions up to {approx}30 and {approx}40 GPa, respectively. For the far-IR experiment, no pressurizing medium was used, whereas KBr was utilized as a pressurizing medium for the mid-IR experiment. For both experiments, pressure was cycled and IR spectra were recorded at various pressures to ascertain sample survival. In the high frequency region ({approx}3000 cm{sup -1}) of the mid-IR spectra, the peak frequencies of the NH{sub 2} symmetric and antisymmetric vibrational modes steadily decrease with increasing pressure, indicating strengthening of intermolecular hydrogen bonding with pressure. In both experiments, no apparent phase transition was observed to the highest pressures studied.

  17. Aerobic Degradation of 2,4,6-Trinitrotoluene by Enterobacter cloacae PB2 and by Pentaerythritol Tetranitrate Reductase

    PubMed Central

    French, Christopher E.; Nicklin, Stephen; Bruce, Neil C.

    1998-01-01

    Enterobacter cloacae PB2 was originally isolated on the basis of its ability to utilize nitrate esters, such as pentaerythritol tetranitrate (PETN) and glycerol trinitrate, as the sole nitrogen source for growth. The enzyme responsible is an NADPH-dependent reductase designated PETN reductase. E. cloacae PB2 was found to be capable of slow aerobic growth with 2,4,6-trinitrotoluene (TNT) as the sole nitrogen source. Dinitrotoluenes were not produced and could not be used as nitrogen sources. Purified PETN reductase was found to reduce TNT to its hydride-Meisenheimer complex, which was further reduced to the dihydride-Meisenheimer complex. Purified PETN reductase and recombinant Escherichia coli expressing PETN reductase were able to liberate nitrogen as nitrite from TNT. The ability to remove nitrogen from TNT suggests that PB2 or recombinant organisms expressing PETN reductase may be useful for bioremediation of TNT-contaminated soil and water. PMID:9687442

  18. Aerobic degradation of 2,4,6-trinitrotoluene by Enterobacter cloacae PB2 and by pentaerythritol tetranitrate reductase

    SciTech Connect

    French, C.E.; Bruce, N.C.; Nicklin, S.

    1998-08-01

    Enterobacter cloacae PB2 was originally isolated on the basis of its ability to utilize nitrate esters, such as pentaerythritol tetranitrate (PETN) and glycerol trinitrate, as the sole nitrogen source for growth. The enzyme responsible is an NADPH-dependent reductase designated PETN reductase. E. cloacae PB2 was found to be capable of slow aerobic growth with 2,4,6-trinitrotoluene (TNT) as the sole nitrogen source. Dinitrotoluenes were not produced and could not be used as nitrogen sources. Purified PETN reductase was found to reduce TNT to its hydride-Meisenheimer complex, which was further reduced to the dihydride-Meisenheimer complex. Purified PETN reductase and recombinant Escherichia coli expressing PETN reductase were able to liberate nitrogen as nitrite from TNT. The ability to remove nitrogen from TNT suggests that PB2 or recombinant organisms expressing PETN reductase may be useful for bioremediation of TNT-contaminated soil and water.

  19. Far infrared supplement. Third edition: Catalog of infrared observations (lambda greater than or equal to 4.6 micrometers)

    NASA Technical Reports Server (NTRS)

    Gezari, Daniel Y.; Schmitz, Marion; Pitts, Patricia S.; Mead, Jaylee M.

    1993-01-01

    The Far Infrared Supplement contains a subset of the data in the full Catalog of Infrared Observations (all observations at wavelengths greater than 4.6 microns). The Catalog of Infrared Observations (CIO), NASA RP-1294, is a compilation of infrared astronomical observational data obtained from an extensive literature search of scientific journals and major astronomical catalogs and surveys. The literature search is complete for years 1965 through 1990 in this third edition. The catalog contains about 210,000 observations of roughly 20,000 individual sources, and supporting appendices. The expanded third edition contains coded IRAS 4-band data for all CIO sources detected by IRAS. The appendices include an atlas of infrared source positions (also included in this volume), two bibliographies of catalog listings, and an atlas of infrared spectral ranges. The complete CIO database is available to qualified users in printed, microfiche, and magnetic tape formats.

  20. Photo-fragmentation cross-section of gaseous 2,4,6-trinitrotoluene at different ultraviolet wavelengths.

    PubMed

    Sharma, Ramesh C; Miller, Tracy S; Usachev, Alexander D; Singh, Jagdish P; Yueh, Fang-Yu; Monts, David L

    2009-04-01

    The photo-fragmentation cross-section of 2,4,6-trinitrotoluene (TNT) vapor at room temperature was determined at different ultraviolet wavelengths (254, 300, 340, and 400 nm) by measuring the concentration of NO molecule with cavity ring down spectroscopy and correcting for the photo-fragmentation cross-section of NO(2). Nitric oxide (NO) molecules are produced by the TNT photo-fragmentation processes via an intermediate production of NO(2). Our results reveal that the photo-fragmentation cross-section of TNT changes appreciably with change in wavelength with xenon arc lamp illumination, increasing with decreasing excitation wavelength. The maximum value of cross-section was observed at the shortest photo-fragmentation wavelength studied (254 nm), which is closest to the wavelength of an absorption peak of TNT near 220 nm.

  1. 2,4,6-Tris(2,2,2-trinitroethylamino)-1,3,5-triazine: Synthesis, Characterization, and Energetic Properties

    NASA Astrophysics Data System (ADS)

    Li, Shenghua; Zhang, Weiwei; Wang, Yuan; Zhao, Xiuxiu; Zhang, Lubo; Pang, Siping

    2014-05-01

    A simple and straightforward route for the synthesis of 2,4,6-tris(2,2,2-trinitroethylamino)-1,3,5-triazine (TTET) has been developed. The compound was fully characterized by multinuclear (1H, 13C) magnetic resonance and infrared (IR) spectroscopy, elemental analysis, electron ionization-mass spectrometry, and differential scanning calorimetry (DSC). TTET was found to have good physical properties, such as good thermal stability (Td = 186°C), reasonable impact sensitivity (21.5 J), and high density (1.88 g . cm-3). Additionally, the detonation properties of TTET obtained with the empirical Kamlet-Jacobs equations identify it as a competitively energetic compound, which in some cases is superior to 1,3,5-Trinitroperhydro-1,3,5-triazine.

  2. 1-(2,4,6-Trialkylphenyl)-1H-Phospholes with a Flattened P-Pyramid: Synthesis and Reactivity

    NASA Astrophysics Data System (ADS)

    Keglevich, György

    The 1H-phospholes with a 2,4,6-trialkylphenyl substituent on the phosphorus atom synthesized in our laboratories are of aromatic character due to their flattened P-pyramid. Hence, they may undergo aromatic electrophilic substitution, such as Friedel-Crafts acylations. The arylphospholes were functionalized via the regioselective reaction with phosphorus tribromide to give substituted phospholes that may be ligands in rhodium complexes used in hydro-formylations. Despite their aromaticity, the arylphospholes may be involved in Diels-Alder cycloaddition with dienophiles to provide 7-phosphanorbornene derivatives useful in fragmentation - related phosphorylations. At elevated temperature, the aryl-1H-phospholes were converted to the 2H-derivatives by a sigmatropic rearrangement to furnish, after trapping, 1-phosphanorbornadienes. The complexation and the oxidation reactions of the sterically hindered arylphospholes are also discussed.

  3. High resolution X-ray structure of dTDP-glucose 4,6-dehydratase from Streptomyces venezuelae.

    PubMed

    Allard, Simon T M; Cleland, W W; Holden, Hazel M

    2004-01-16

    Desosamine is a 3-(dimethylamino)-3,4,6-trideoxyhexose found in some macrolide antibiotics. In Streptomyces venezuelae, there are seven genes required for the biosynthesis of this unusual sugar. One of the genes, desIV, codes for a dTDP-glucose 4,6-dehydratase, which is referred to as DesIV. The reaction mechanisms for these types of dehydratases are quite complicated with proton abstraction from the sugar 4'-hydroxyl group and hydride transfer to NAD+, proton abstraction at C-5, and elimination of the hydroxyl group at C-6 of the sugar, and finally return of a proton to C-5 and a hydride from NADH to C-6. Here we describe the cloning, overexpression, and purification, and high resolution x-ray crystallographic analysis to 1.44 A of wild-type DesIV complexed with dTDP. Additionally, for this study, a double site-directed mutant protein (D128N/E129Q) was prepared, crystallized as a complex with NAD+ and the substrate dTDP-glucose and its structure determined to 1.35 A resolution. In DesIV, the phenolate group of Tyr(151) and O(gamma) of Thr(127) lie at 2.7 and 2.6 A, respectively from the 4'-hydroxyl group of the dTDP-glucose substrate. The side chain of Asp(128) is in the correct position to function as a general acid for proton donation to the 6'-hydroxyl group while the side chain of Glu(129) is ideally situated to serve as the general base for proton abstraction at C-5. This investigation provides further detailed information for understanding the exquisite chemistry that occurs in these remarkable enzymes.

  4. Pseudomonas aeruginosa strain MA01 aerobically metabolizes the aminodinitrotoluenes produced by 2,4,6-trinitrotoluene nitro group reduction.

    PubMed

    Alvarez, M A; Kitts, C L; Botsford, J L; Unkefer, P J

    1995-11-01

    Many microbes reduce the nitro substituents of 2,4,6-trinitrotoluene (TNT), producing aminodinitrotoluenes (ADNTs). These compounds are recalcitrant to further breakdown and are acutely toxic. In a search for organisms capable of metabolizing ADNTs, a bacterial strain was isolated for the ability to use 2-aminobenzoate (anthranilate) as sole C-source. This isolate, Pseudomonas aeruginosa MA01, metabolized TNT by first reducing one nitro group to form either 2-amino-4,6-dinitrotoluene (2ADNT) or 4-amino-2,6-dinitrotoluene (4ADNT). However, strain MA01 was distinct from other TNT-reducing organisms in that it transformed these compounds into highly polar metabolites through an O2-dependent process. Strain MA01 was able to cometabolize TNT, 2ADNT, and 4ADNT in the presence of a variety of carbon and energy sources. During aerobic cometabolism with succinate, 45% of uniformly ring-labeled [14C]TNT was transformed to highly polar compounds. Aerobic cometabolism of purified [14C]2ADNT and [14C]4ADNT with succinate as C-source produced similar amounts of these polar metabolites. During O2-limited cometabolism with succinate as C-source and nitrate as electron acceptor, less than 8% of the [14C]TNT was transformed to polar metabolites. Purified 2,6-diamino-4-nitrotoluene was not metabolized, and while 2,4-diamino-6-nitrotoluene was acetylated, the product (N-acetyl-2,4-diamino-6-nitrotoluene) was not further metabolized. Therefore, strain MA01 metabolized TNT by oxidation of the ADNTs and not by reduction the remaining nitro groups on the ADNTs.

  5. Characterization of partial anaerobic metabolic pathway for 2,4,6-trinitrotoluene degradation by a sulfate-reducing bacterial consortium.

    PubMed

    Boopathy, R; Manning, J F

    1996-12-01

    The anaerobic degradative pathway for metabolism of 2,4,6-trinitrotoluene (TNT) by a consortium of Desulfovibrio spp. isolated from a creek sediment was studied. This consortium has the metabolic capability to degrade TNT to fatty acids. The growth of the consortium and the metabolism of TNT were greatly enhanced in the presence of an additional carbon source like pyruvate. The optimal concentration of pyruvate for the maximum rate of TNT degradation was 15-20 mM. Various intermediates of TNT metabolism were identified. The first step in the pathway was reduction of TNT to 4-amino-2,6-dinitrotoluene and 2-amino-4,6-dinitrotoluene, which were further reduced to 2,4-diamino,6-nitrotoluene. The next intermediate to appear in the culture medium was nitrobenzoic acid, followed by cyclohexanone, 2-methyl pentanoic acid, butyric acid, and acetic acid. A study using radiolabeled TNT showed that no CO2 was produced from TNT during metabolism. The mass balance of the radiolabeled study showed that 49.6% of the TNT was converted to acetic acid, 28% was assimilated into biomass as trichloroacetic acid precipitable materials, and the rest was distributed as various TNT intermediates. Most Desulfovibrio spp. are incomplete oxidizers that are unable to carry out the terminal oxidation of organic substrates. The major end product of TNT metabolism was acetic acid. The bacteria grew on all the TNT intermediates tested as sole source of carbon, except on acetic acid, confirming that the Desulfovibrio spp. have the enzymes necessary for complete degradation of TNT to acetate.

  6. Transformation of 2,4,6-Trinitrotoluene by Purified Xenobiotic Reductase B from Pseudomonas fluorescens I-C

    PubMed Central

    Pak, Jeong W.; Knoke, Kyle L.; Noguera, Daniel R.; Fox, Brian G.; Chambliss, Glenn H.

    2000-01-01

    The enzymatic transformation of 2,4,6-trinitrotoluene (TNT) by purified XenB, an NADPH-dependent flavoprotein oxidoreductase from Pseudomonas fluorescens I-C, was evaluated by using natural abundance and [U-14C]TNT preparations. XenB catalyzed the reduction of TNT either by hydride addition to the aromatic ring or by nitro group reduction, with the accumulation of various tautomers of the protonated dihydride-Meisenheimer complex of TNT, 2-hydroxylamino-4,6-dinitrotoluene, and 4-hydroxylamino-2,6-dinitrotoluene. Subsequent reactions of these metabolites were nonenzymatic and resulted in predominant formation of at least three dimers with an anionic m/z of 376 as determined by negative-mode electrospray ionization mass spectrometry and the release of ∼0.5 mol of nitrite per mol of TNT consumed. The extents of the initial enzymatic reactions were similar in the presence and in the absence of O2, but the dimerization reaction and the release of nitrite were favored under aerobic conditions or under anaerobic conditions in the presence of NADP+. Reactions of chemically and enzymatically synthesized and high-pressure liquid chromatography-purified TNT metabolites showed that both a hydroxylamino-dinitrotoluene isomer and a tautomer of the protonated dihydride-Meisenheimer complex of TNT were required precursors for the dimerization and nitrite release reactions. The m/z 376 dimers also reacted with either dansyl chloride or N-1-naphthylethylenediamine HCl, providing evidence for an aryl amine functional group. In combination, the experimental results are consistent with assigning the chemical structures of the m/z 376 species to various isomers of amino-dimethyl-tetranitrobiphenyl. A mechanism for the formation of these proposed TNT metabolites is presented, and the potential enzymatic and environmental significance of their formation is discussed. PMID:11055918

  7. Isomorphous Substitution of Rare-Earth Elements in Lacunary Apatite Pb8Na2(PO4)6.

    PubMed

    Get'man, Evgeni I; Loboda, Stanislav N; Ignatov, Alexey V; Prisedsky, Vadim V; Abdul Jabar, Mohammed A B; Ardanova, Lyudmyla I

    2016-03-07

    The substitution of rare-earth elements (REEs) for Pb in the lacunary apatite Pb8Na2(PO4)6 with void structural channels was studied by means of powder X-ray diffraction (including the Rietveld refinement), scanning electron microscopy, energy-dispersive X-ray microanalysis, and IR spectroscopy and also measurements of the electrical conductivity. The substitution limits (xmax in Pb8-xLnxNa2(PO4)6Ox/2) at 800 °C were found to decrease with the atomic number of the REE from 1.40 for La to 0.12 for Yb with a rapid drop from light to heavy lanthanides (between Gd and Tb). The REE atoms substitute for Pb predominantly at Pb2 sites of the apatite structure according to the scheme 2Pb(2+) + □ → 2Ln(3+) + O(2-), where □ is a vacancy in the structural channel. The substitution in lacunary apatite produces quite different changes in the structural parameters compared with broadly studied alkaline-earth hydroxyapatites. In spite of the much lower ionic radii of REE than that of Pb(2+), the mean distances ⟨Pb1-O⟩ somewhat increase, whereas the distances ⟨Pb2-Pb2⟩ and ⟨Pb2-O4⟩ do not change considerably with the degree of substitution. This implies control of the substitution by not only spatial and charge accommodation of REE ions but also the availability of a stereochemically active 6s(2) electron pair on Pb(2+). The high-temperature electrical conductivity shows dependence on the degree of substitution with a minimum at x = 0.2 indicative of a possible change of the type of conductivity.

  8. DNA damage induced by 4,6,8,9-tetramethyl-2H-furo[2,3-h]quinolin-2-one, a new furocoumarin analog: photochemical mechanisms.

    PubMed

    Bordin, F; Baccichetti, F; Marzano, C; Carlassare, F; Miolo, G; Chilin, A; Guiotto, A

    2000-03-01

    Some photochemical and photobiological properties of 4,6,8,9-tetramethyl-2H-furo[2,3-h]quinolin-2-one (HFQ) were studied in comparison with its isomer 1,4,6,8-tetramethyl-2H-furo[2,3-h]quinolin-2-one (FQ) and 8-methoxypsoralen (8-MOP). The HFQ photobinds to DNA forming furan-side monoadducts (MAHFQ) that have molecular structure very similar to those of FQ (MAFQ). Unlike MA8-MOP and MAFQ, MAHFQ no longer photoreact. The HFQ, like FQ, produces moderate amounts of singlet oxygen but no superoxide anions. The HFQ and FQ induce numbers of DNA-protein cross-links (DPC), much more plentiful than those of 8-MOP (about two and seven times, respectively) but no interstrand cross-links. The mechanism of DPC formation was studied in vivo in mammalian cells by alkaline elution and in vitro using a new test mixing histones and DNA from calf thymus. The latter is a very useful technique for the double irradiation protocol. The DNA (or histones) are separately exposed to a first UVA dose in the presence of the sensitizer; then, after its unbound molecules have been removed, histones (or DNA) are added to assemble the chromatin-like complex that is irradiated again. According to in vitro and in vivo methods, DPC appear to be formed by FQ and 8-MOP by a biphotonic process that starts with monoadduct induction in DNA, followed by their conversion into DPC. In the resulting lesions, the sensitizer molecule forms a covalent bridge between the two macromolecules (DPC at length greater than zero). Instead, HFQ induces DPC by a monophotonic process; thus, HFQ is probably not a physical part of the bridge between DNA and proteins, which may be linked together directly, like DPC at zero length induced by UVC.

  9. DNA damage induced by 4,6,8,9-tetramethyl-2H-furo[2,3-h]quinolin-2-one, a new furocoumarin analog: biological consequences.

    PubMed

    Marzano, C; Baccichetti, F; Carlassare, F; Chilin, A; Lora, S; Bordin, F

    2000-03-01

    4,6,8,9-Tetramethyl-2H-furo[2,3-h]quinolin-2-one (HFQ) and its isomer FQ (1,4,6,8-tetramethyl-2H-furo[2,3-h]quinolin-2-one) showed very strong antiproliferative activity in mammalian cells, about two times greater than 8-methoxypsoralen (8-MOP). Both compounds induced DNA-protein cross-links (DPC) but not interstrand cross-links. The FQ generated DPC in a biphotonic process, yielding a new kind of diadduct, whereas HFQ induced DPC by a monophotonic one, probably without its physical participation in the covalent bridge. These lesions gave different toxic responses. Sensitization of FQ led to extensive DNA fragmentation and to a number of chromosomal aberrations. Conversely, HFQ seemed to be completely inactive and 8-MOP gave intermediate results. A strict relationship between DPC formation and induction of chromosomal aberrations was observed. The HFQ did not induce light skin erythemas, whereas FQ was more phototoxic than 8-MOP, thus suggesting that FQ lesions, DPC in particular, may be implicated in skin phototoxicity. Ehrlich ascites cells, a transplantable mouse tumor, inactivated by furoquinolinone sensitization and injected into healthy mice, protected them from a successive challenge by viable tumor cells. This response appeared to be based on an immune mechanism. Comparable amounts of base substitution revertants were scored when testing furoquinolinones and 8-MOP in bacteria but no DPC were detected. This suggests that classic mutagenesis tests on bacteria are insufficient to give adequate information on furocoumarin genotoxicity. Given its features, HFQ can be regarded as an interesting new agent for psoralen plus UVA photochemotherapy and photopheresis.

  10. Technology, Time and Transition in Higher Education--Two Different Realities of Everyday "Facebook" Use in the First Year of University in the UK

    ERIC Educational Resources Information Center

    Stirling, Eve

    2016-01-01

    Within the range of websites and apps that are part of first-year undergraduates' digital environments, the social network site "Facebook" is perhaps the most popular and prominent. As such, the ubiquitous nature of "Facebook" in the higher education landscape has drawn much attention from scholars. Drawing on data from a…

  11. Providing Higher Education in Post-Modern Times: What Do University Mission Statements Tell Us about What They Believe and Do?

    ERIC Educational Resources Information Center

    Ellis, Jennifer; Miller, Paul

    2014-01-01

    Higher education institutions (HEIs) are critical to the delivery of education for all in any nation state. What they believe and what they do are critical components to creating societal impact. But what they believe and do is not always clear. Using a derivative of SWIFT (Structured Word Identification and Frequency Totals), the authors examined…

  12. Assessing the Impact of a Statewide STEM Investment on K-12, Higher Education, and Business/Community STEM Awareness over Time

    ERIC Educational Resources Information Center

    Sondergeld, Toni A.; Johnson, Carla C.; Walten, Janet B.

    2016-01-01

    Despite monetary and educational investments in science, technology, engineering, and mathematics (STEM) being at record high levels, little attention has been devoted to generating a common understanding of STEM. In addition, working with business, K-12 schools, and/or institutions of higher education to establish a grassroots effort to help…

  13. Rb and FZR1/Cdh1 determine CDK4/6-cyclin D requirement in C. elegans and human cancer cells.

    PubMed

    The, Inge; Ruijtenberg, Suzan; Bouchet, Benjamin P; Cristobal, Alba; Prinsen, Martine B W; van Mourik, Tim; Koreth, John; Xu, Huihong; Heck, Albert J R; Akhmanova, Anna; Cuppen, Edwin; Boxem, Mike; Muñoz, Javier; van den Heuvel, Sander

    2015-01-06

    Cyclin-dependent kinases 4 and 6 (CDK4/6) in complex with D-type cyclins promote cell cycle entry. Most human cancers contain overactive CDK4/6-cyclin D, and CDK4/6-specific inhibitors are promising anti-cancer therapeutics. Here, we investigate the critical functions of CDK4/6-cyclin D kinases, starting from an unbiased screen in the nematode Caenorhabditis elegans. We found that simultaneous mutation of lin-35, a retinoblastoma (Rb)-related gene, and fzr-1, an orthologue to the APC/C co-activator Cdh1, completely eliminates the essential requirement of CDK4/6-cyclin D (CDK-4/CYD-1) in C. elegans. CDK-4/CYD-1 phosphorylates specific residues in the LIN-35 Rb spacer domain and FZR-1 amino terminus, resembling inactivating phosphorylations of the human proteins. In human breast cancer cells, simultaneous knockdown of Rb and FZR1 synergistically bypasses cell division arrest induced by the CDK4/6-specific inhibitor PD-0332991. Our data identify FZR1 as a candidate CDK4/6-cyclin D substrate and point to an APC/C(FZR1) activity as an important determinant in response to CDK4/6-inhibitors.

  14. Rb and FZR1/Cdh1 determine CDK4/6-cyclin D requirement in C. elegans and human cancer cells

    PubMed Central

    The, Inge; Ruijtenberg, Suzan; Bouchet, Benjamin P.; Cristobal, Alba; Prinsen, Martine B. W.; van Mourik, Tim; Koreth, John; Xu, Huihong; Heck, Albert J. R.; Akhmanova, Anna; Cuppen, Edwin; Boxem, Mike; Muñoz, Javier; van den Heuvel, Sander

    2015-01-01

    Cyclin-dependent kinases 4 and 6 (CDK4/6) in complex with D-type cyclins promote cell cycle entry. Most human cancers contain overactive CDK4/6-cyclin D, and CDK4/6-specific inhibitors are promising anti-cancer therapeutics. Here, we investigate the critical functions of CDK4/6-cyclin D kinases, starting from an unbiased screen in the nematode Caenorhabditis elegans. We found that simultaneous mutation of lin-35, a retinoblastoma (Rb)-related gene, and fzr-1, an orthologue to the APC/C co-activator Cdh1, completely eliminates the essential requirement of CDK4/6-cyclin D (CDK-4/CYD-1) in C. elegans. CDK-4/CYD-1 phosphorylates specific residues in the LIN-35 Rb spacer domain and FZR-1 amino terminus, resembling inactivating phosphorylations of the human proteins. In human breast cancer cells, simultaneous knockdown of Rb and FZR1 synergistically bypasses cell division arrest induced by the CDK4/6-specific inhibitor PD-0332991. Our data identify FZR1 as a candidate CDK4/6-cyclin D substrate and point to an APC/CFZR1 activity as an important determinant in response to CDK4/6-inhibitors. PMID:25562820

  15. (4E)-dehydrocitrals [(2E,4E)- and (2Z,4E )-3,7-dimethyl-2,4,6-octatrienals] from acarid mite Histiogaster sp. A096 (Acari: Acaridae).

    PubMed

    Hiraoka, H; Mori, N; Nishida, R; Kuwahara, Y

    2001-12-01

    A mixture of two monoterpenes was obtained as the opisthonotal gland secretion from unidentified Histiogaster sp. A096 (Acari: Acaridae), and their structures were elucidated to be (4E)-dehydrocitrals [(2E,4E)- and (2Z,4E)-3,7-dimethyl-2,4,6-octatrienals] by GC/MS, GC/FT-IR, UV and 1H-NMR spectra. Both isomers of (4E)-dehydrocitral prepared by syntheses in 4 steps from 3-methyl-2-butenal with 34.2% yields (based on the ylide) were separated by column chromatography into the (2E,4E)- and (2Z,4E)-3,7-dimethyl-2,4,6-octatrienal. Mass spectra together with GC retention times of the purified natural (4E)-dehydrocitrals were identical with those of synthetic (2E,4E)-3,7-dimethyl-2,4,6-octatrienal and (2Z,4E)-3,7-dimethyl-2,4,6-octatrienal. The geometry at the 2-C position of both synthetic (4E)-dehydrocitrals was confirmed by NOESY analyses. This is the first identification of (4E)-dehydrocitrals from the animal kingdom.

  16. Disposition of acetaminophen at 4, 6, and 8 g/day for 3 days in healthy young adults.

    PubMed

    Gelotte, C K; Auiler, J F; Lynch, J M; Temple, A R; Slattery, J T

    2007-06-01

    The objective of this study was to determine the disposition and tolerability of 1, 1.5, and 2 g acetaminophen every 6 h for 3 days. Group I healthy adults received acetaminophen (4 then 6 g/day) or placebo; Group II received acetaminophen (4 then 8 g/day) or placebo. Acetaminophen and metabolites were measured in plasma and urine. Hepatic aminotransferases were measured daily. At steady state, acetaminophen concentrations were surprisingly lower than predicted from single-dose data, although sulfate formation clearance (fCL) was lower as expected, indicating cofactor depletion with possible sulfotransferase saturation. In contrast, glucuronide fCL was unexpectedly higher, strongly suggesting glucuronosyltransferase induction. This is the first evidence that acetaminophen induces its own glucuronidation. No dose-dependent differences were detected in fCL of thiol metabolites formed via cytochrome P4502E1. Hepatic aminotransferases stayed within reference ranges, and the incidence and frequency of adverse events were similar for acetaminophen and placebo. Although dose-dependence of acetaminophen disposition was reported previously, this study shows a novel finding of time-dependent disposition during repeated dosing. Unexpected increases in glucuronide fCL more than offset decreases in sulfate fCL, thus increasing acetaminophen clearance overall. Thiol metabolite fCL remained constant up to 8 g/day. These findings have important implications in short-term (3 day) tolerability of supratherapeutic acetaminophen doses in healthy adults.

  17. First observations of histopathological effects of 2,4,6-trinitrotoluene (TNT) in gills of European eel Anguilla anguilla (Linnaeus, 1758): histopathological effects of 2,4,6-trinitrotoluene in gills of European eel.

    PubMed

    Sensini, Cristiana; Della Torre, Camilla; Corsi, Ilaria; Focardi, Silvano

    2008-12-01

    The aim of the present study was to investigate the effects on gill morphology of the explosive 2,4,6-trinitrotoluene (TNT) in a model fish, the European eel, Anguilla anguilla (Linnaeus, 1758) to assess potential detrimental effects in marine fish due to its presence in dumping areas. Juvenile specimens of A. anguilla were exposed in vivo for 6 and 24 h to 0.5, 1 and 2.5 mg/l nominal concentrations of TNT using dimethyl sulfoxide (0.1 per thousand) as solvent carrier. Histological analysis of gills indicated that TNT induced several structural lesions. After 6h of exposure at 0.5 and 1 mg/l TNT, oedema of some secondary lamellae was evident: this change at the highest dose of 2.5 mg/l led to epithelial lifting and detachment from the endothelium and rupture of the branchial membrane and vascular congestion. After 24 h at 0.5 mg/l, increased oedema in secondary lamellae, extensive epithelial detachment and vascular congestion and dilation of lamellar capillaries and pooling of blood at 1 mg/l were observed. At 2.5 mg/l, epithelial hyperplasia, fusion of adjacent lamellae, obliteration of interlamellar spaces by means of tight junctions were also observed. Moreover, chloride cells proliferated along secondary lamellae, and mucus hypersecretion was evident. The overall results clearly indicate that gills are sensitive targets of TNT.

  18. Matrix effects on the triplet state of the OLED emitter Ir(4,6-dFppy)2(pic) (FIrpic): investigations by high-resolution optical spectroscopy.

    PubMed

    Rausch, Andreas F; Thompson, Mark E; Yersin, Hartmut

    2009-03-02

    The sky-blue emitting compound Ir(4,6-dFppy)(2)(pic) (iridium(III)bis[2-(4',6'-difluorophenyl)pyridinato-N,C(2')]-picolinate), commonly referred to as FIrpic and representing a well-known emitter material for organic light emitting diodes (OLEDs), has been investigated in detail by optical spectroscopy. Studies at temperatures from T = 1.5 K to T = 300 K were carried out in CH(2)Cl(2) and tetrahydrofuran (THF). In CH(2)Cl(2), two discrete sites were observed at cryogenic temperatures and studied by site-selective, high-resolution spectroscopy. The investigations reveal that the molecules located at the two sites exhibit distinctly different photophysical properties. For example, the three substates I, II, and III of the emitting triplet state T(1) of the low-energy site A show a distinctly larger zero-field splitting (ZFS) and exhibit shorter individual decay times than observed for the high-energy site B. The vibrational satellite structures in the emission spectra of the substates I(A) and I(B) exhibit clear differences in the ranges of metal-ligand (M-L) vibrations. For the compound studied in a polycrystalline THF host, giving only strongly inhomogeneously broadened spectra, the ZFS parameters and substate decay times vary in a similar range as observed for the two discrete sites in the CH(2)Cl(2) matrix. Thus, the amount of ZFS, the emission decay times, and also the intensities of the M-L vibrational satellites are affected by the matrix cage, that is, the host environment of the emitting complex. These properties are discussed with respect to variations of spin-orbit coupling routes. In particular, changes of d-orbital admixtures, that is, differences of the metal-to-ligand charge transfer (MLCT) character in the emitting triplet, play an important role. The matrix effects are expected to be also of importance for FIrpic and other Ir(III) compounds when applied as emitters in amorphous OLED matrixes.

  19. The Use of Quantile Regression to Forecast Higher Than Expected Respiratory Deaths in a Daily Time Series: A Study of New York City Data 1987-2000

    PubMed Central

    Soyiri, Ireneous N.; Reidpath, Daniel D.

    2013-01-01

    Forecasting higher than expected numbers of health events provides potentially valuable insights in its own right, and may contribute to health services management and syndromic surveillance. This study investigates the use of quantile regression to predict higher than expected respiratory deaths. Data taken from 70,830 deaths occurring in New York were used. Temporal, weather and air quality measures were fitted using quantile regression at the 90th-percentile with half the data (in-sample). Four QR models were fitted: an unconditional model predicting the 90th-percentile of deaths (Model 1), a seasonal / temporal (Model 2), a seasonal, temporal plus lags of weather and air quality (Model 3), and a seasonal, temporal model with 7-day moving averages of weather and air quality. Models were cross-validated with the out of sample data. Performance was measured as proportionate reduction in weighted sum of absolute deviations by a conditional, over unconditional models; i.e., the coefficient of determination (R1). The coefficient of determination showed an improvement over the unconditional model between 0.16 and 0.19. The greatest improvement in predictive and forecasting accuracy of daily mortality was associated with the inclusion of seasonal and temporal predictors (Model 2). No gains were made in the predictive models with the addition of weather and air quality predictors (Models 3 and 4). However, forecasting models that included weather and air quality predictors performed slightly better than the seasonal and temporal model alone (i.e., Model 3 > Model 4 > Model 2) This study provided a new approach to predict higher than expected numbers of respiratory related-deaths. The approach, while promising, has limitations and should be treated at this stage as a proof of concept. PMID:24147122

  20. The use of quantile regression to forecast higher than expected respiratory deaths in a daily time series: a study of New York City data 1987-2000.

    PubMed

    Soyiri, Ireneous N; Reidpath, Daniel D

    2013-01-01

    Forecasting higher than expected numbers of health events provides potentially valuable insights in its own right, and may contribute to health services management and syndromic surveillance. This study investigates the use of quantile regression to predict higher than expected respiratory deaths. Data taken from 70,830 deaths occurring in New York were used. Temporal, weather and air quality measures were fitted using quantile regression at the 90th-percentile with half the data (in-sample). Four QR models were fitted: an unconditional model predicting the 90th-percentile of deaths (Model 1), a seasonal/temporal (Model 2), a seasonal, temporal plus lags of weather and air quality (Model 3), and a seasonal, temporal model with 7-day moving averages of weather and air quality. Models were cross-validated with the out of sample data. Performance was measured as proportionate reduction in weighted sum of absolute deviations by a conditional, over unconditional models; i.e., the coefficient of determination (R1). The coefficient of determination showed an improvement over the unconditional model between 0.16 and 0.19. The greatest improvement in predictive and forecasting accuracy of daily mortality was associated with the inclusion of seasonal and temporal predictors (Model 2). No gains were made in the predictive models with the addition of weather and air quality predictors (Models 3 and 4). However, forecasting models that included weather and air quality predictors performed slightly better than the seasonal and temporal model alone (i.e., Model 3 > Model 4 > Model 2) This study provided a new approach to predict higher than expected numbers of respiratory related-deaths. The approach, while promising, has limitations and should be treated at this stage as a proof of concept.