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Sample records for marko kaasik tnu

  1. Strong molecular traffic control effect in TNU-9 zeolite channel topology.

    PubMed

    Chatterjee, Sakuntala; Harish, Ramanna; Schütz, Gunter M

    2011-12-29

    Reactivity enhancement in a catalytic zeolite grain through molecular traffic control (MTC) rests on the basic notion that the reactant and product molecules prefer to diffuse along different channels inside the grain and therefore do not mutually hinder their transport in and out of the grain. We investigate the conditions of reactivity enhancement in the presence of MTC for a realistic channel topology that describes the pore structure of a TNU-9 zeolite. We compare the output current of an MTC system with a reference system, which does not show any channel selectivity. For a wide range of reaction rates and for different grain sizes, we find that there is a very significant enhancement of reactivity for the MTC system. This effect remains strong as the grain size increases. The mechanism behind reactivity enhancement is argued to be generic rather than being confined to the particular structure of TNU-9.

  2. Study of the effects of solar activities on the ionosphere as observed by VLF signals recorded at TNU station, Vietnam

    NASA Astrophysics Data System (ADS)

    Tan, L. M.

    2015-12-01

    A SuperSID monitor installed at Tay Nguyen University (TNU), Vietnam is used to detect the temporal variations of Very Low Frequency (VLF) signals during 2013 and 2014 to understand the responses of the ionosphere to sunset/sunrise transitions and solar flares. Two VLF station signals are tracked, JJI/22.2 kHz in Japan and NWC/19.8 kHz in Australia. Results show that the effects of sunrise, sunset and solar flares on the NWC signal are more significantly different than those on the JJI signal. Sunset and sunrise spikes only occur on the JJI-TNU path because of longitudinal differences between the receiver and transmitter. Two sunset dips and three sunrise dips appear on the NWC signal during summer season. During intense solar flares, the dips occur after the maximum disturbance of the VLF signals for the North-South path. The appearance of these dips is explained by modal interference patterns. Observing temporal variations of sunrise and sunset dips or spikes of VLF signals during different seasons enhances the understanding of the behavior of the ionosphere.

  3. Kosta Marko Cepenkov "healer of the poor", "poor man's doctor" from Prilep. A contribution to the history of folk medicine in Macedonia.

    PubMed

    Polenakovic, M

    2007-12-01

    This contribution is about Kosta Marko Cepenkov, a medicater from 19th century from Prilep. The data about the treatment of diseases have been collected from the Authobiography of his son, Marko Cepenkov, the famous collector of Macedonian folk literature. The Autobiography was published in 1958 in Slavistics journal Macedonian Language in Skopje (Year IX, Vol. 1-2, 109-145). PMID:18356792

  4. Current Level and Correlates of Traditional Cooking Energy Sources Utilization in Urban Settings in the Context of Climate Change and Health, Northwest Ethiopia: A Case of Debre Markos Town

    PubMed Central

    Geremew, Kumlachew; Gedefaw, Molla; Dagnew, Zewdu; Jara, Dube

    2014-01-01

    Background. Traditional biomass has been the major source of cooking energy for major segment of Ethiopian population for thousands of years. Cognizant of this energy poverty, the Government of Ethiopia has been spending huge sum of money to increase hydroelectric power generating stations. Objective. To assess current levels and correlates of traditional cooking energy sources utilization. Methods. A community based cross-sectional study was conducted employing both quantitative and qualitative approaches on systematically selected 423 households for quantitative and purposively selected 20 people for qualitative parts. SPSS version 16 for windows was used to analyze the quantitative data. Logistic regression was fitted to assess possible associations and its strength was measured using odds ratio at 95% CI. Qualitative data were analyzed thematically. Result. The study indicated that 95% of households still use traditional biomass for cooking. Those who were less knowledgeable about negative health and environmental effects of traditional cooking energy sources were seven and six times more likely to utilize them compared with those who were knowledgeable (AOR (95% CI) = 7.56 (1.635, 34.926), AOR (95% CI) = 6.68 (1.80, 24.385), resp.). The most outstanding finding of this study was that people use traditional energy for cooking mainly due to lack of the knowledge and their beliefs about food prepared using traditional energy. That means “…people still believe that food cooked with charcoal is believed to taste delicious than cooked with other means.”  Conclusion. The majority of households use traditional biomass for cooking due to lack of knowledge and belief. Therefore, mechanisms should be designed to promote electric energy and to teach the public about health effects of traditional cooking energy source. PMID:24895591

  5. Postnatal Care Service Utilization and Associated Factors among Women Who Gave Birth in the Last 12 Months prior to the Study in Debre Markos Town, Northwestern Ethiopia: A Community-Based Cross-Sectional Study.

    PubMed

    Limenih, Miteku Andualem; Endale, Zerfu Mulaw; Dachew, Berihun Assefa

    2016-01-01

    Improving maternal and newborn health through proper postnatal care services under the care of skilled health personnel is the key strategy to reduce maternal and neonatal mortality. However, there were limited evidences on utilization of postnatal care services in Ethiopia. A community based cross-sectional study was conducted in Debremarkos town, Northwest Ethiopia. Cluster sampling technique was used to select 588 study participants. Bivariate and multivariable logistic regression model was fitted to identify factors associated with postnatal care utilization. Odds ratio with 95% confidence interval was computed to determine the level of significance. Postnatal care service utilization was found to be 33.5%. Awareness about maternal complication (AOR: 2.72, 95% CI (1.71, 4.34)), place of delivery of last child (AOR: 1.68, 95% CI: (1.01, 2.79)), outcome of birth (AOR: 2.71, 95% CI (1.19, 6.19)), delivery by cesarean section (AOR: 4.82, 95% CI (1.86, 12.54)), and delivery complication that occurred during birth (AOR: 2.58, 95% CI (1.56, 4.28)) were factors associated with postnatal care service utilization. Postnatal care service utilization was found to be low. Increasing awareness about postnatal care, preventing maternal and neonatal complication, and scheduling mothers based on the national postnatal care follow-up protocol would increase postnatal care service utilization. PMID:27433481

  6. Postnatal Care Service Utilization and Associated Factors among Women Who Gave Birth in the Last 12 Months prior to the Study in Debre Markos Town, Northwestern Ethiopia: A Community-Based Cross-Sectional Study.

    PubMed

    Limenih, Miteku Andualem; Endale, Zerfu Mulaw; Dachew, Berihun Assefa

    2016-01-01

    Improving maternal and newborn health through proper postnatal care services under the care of skilled health personnel is the key strategy to reduce maternal and neonatal mortality. However, there were limited evidences on utilization of postnatal care services in Ethiopia. A community based cross-sectional study was conducted in Debremarkos town, Northwest Ethiopia. Cluster sampling technique was used to select 588 study participants. Bivariate and multivariable logistic regression model was fitted to identify factors associated with postnatal care utilization. Odds ratio with 95% confidence interval was computed to determine the level of significance. Postnatal care service utilization was found to be 33.5%. Awareness about maternal complication (AOR: 2.72, 95% CI (1.71, 4.34)), place of delivery of last child (AOR: 1.68, 95% CI: (1.01, 2.79)), outcome of birth (AOR: 2.71, 95% CI (1.19, 6.19)), delivery by cesarean section (AOR: 4.82, 95% CI (1.86, 12.54)), and delivery complication that occurred during birth (AOR: 2.58, 95% CI (1.56, 4.28)) were factors associated with postnatal care service utilization. Postnatal care service utilization was found to be low. Increasing awareness about postnatal care, preventing maternal and neonatal complication, and scheduling mothers based on the national postnatal care follow-up protocol would increase postnatal care service utilization.

  7. Regional study of the Archean to Proterozoic crust at the Sudbury Neutrino Observatory (SNO+), Ontario: Predicting the geoneutrino flux

    NASA Astrophysics Data System (ADS)

    Huang, Yu; Strati, Virginia; Mantovani, Fabio; Shirey, Steven B.; McDonough, William F.

    2014-10-01

    SNO+ detector that is currently under construction in Ontario, Canada, will be a new kiloton-scale liquid scintillation detector with the capability of recording geoneutrino events that can be used to constrain the strength of the Earth's radiogenic power, and in turn, to test compositional models of the bulk silicate Earth (BSE). We constructed a detailed 3-D model of the regional crust centered at SNO+ from compiled geological, geophysical, and geochemical information. Crustal cross sections obtained from refraction and reflection seismic surveys were used to characterize the crust and assign uncertainties to its structure. The average Moho depth in the study area is 42.3 ± 2.6 km. The upper crust was divided into seven dominant lithologic units on the basis of regional geology. The abundances of U and Th and their uncertainties in each upper crustal lithologic unit were determined from analyses of representative outcrop samples. The average chemical compositions of the middle and lower crust beneath the SNO+ region were determined by coupling local seismic velocity profiles with a global compilation of the chemical compositions of amphibolite and granulite facies rocks. Monte Carlo simulations were used to predict the geoneutrino signal originating from the regional crust at SNO+ and to track asymmetrical uncertainties of U and Th abundances. The total regional crust contribution of the geoneutrino signal at SNO+ is predicted to be 15.6-3.4+5.3 TNU (a Terrestrial Neutrino Unit is one geoneutrino event per 1032 target protons per year), with the Huronian Supergroup near SNO+ dominantly contributing 7.3-3.0+5.0 TNU to this total. Future systematically sampling of this regional unit and denser seismic surveys will better model its composition and structure, and thus reduce the uncertainty on geoneutrino signal at SNO+. The bulk crustal geoneutrino signal at SNO+ is estimated to be 30.7-4.2+6.0 TNU, which is lower than that predicted in a global-scale reference

  8. Ordered Silicon Vacancies in the Framework Structure of the Zeolite Catalyst SSZ-74

    SciTech Connect

    Baerlocher,C.; Xie, D.; McCusker, L.; Hwang, S.; Chan, I.; Ong, K.; Burton, A.; Zones, S.

    2008-01-01

    Physico-chemical characterization of the high-silica zeolite catalyst SSZ-74 (ref. 1) suggested that it, like the related materials TNU-9 (ref. 2) and IM-5 (ref. 3), has a multidimensional 10-ring channel system4. Such pore systems are ideal for many petrochemical applications, and indeed SSZ-74 has been shown to be a good catalyst for a wide variety of reactions1. The elucidation of its framework structure, however, proved to be difficult. Comparable problems were encountered with TNU-9 and IM-5, which were synthesized with related structure-directing agents. Their framework structures, which are the two most complex ones known, both have 24 Si atoms in the asymmetric unit, and were finally solved by combining high-resolution powder diffraction data with information derived from high-resolution electron microscopy images5, 6. Therefore, a similar approach, using the powder charge-flipping algorithm7 to combine the two types of data and molecular modelling to help to locate the structure-directing agent, was applied to SSZ-74. This procedure eventually revealed a most unusual 23-Si-atom framework structure (|(C16H34N2)4|[Si92square4O184(OH)8]) with ordered Si vacancies.

  9. User's Guide and Metadata to Coastal Biodiversity Risk Analysis Tool (CBRAT): Framework for the Systemization of Life History and Biogeographic Information

    EPA Science Inventory

    ABSTRACTUser’s Guide & Metadata to Coastal Biodiversity Risk Analysis Tool (CBRAT): Framework for the Systemization of Life History and Biogeographic Information(EPA/601/B-15/001, 2015, 123 pages)Henry Lee II, U.S. EPA, Western Ecology DivisionKatharine Marko, U.S. EPA,...

  10. Spring Research Festival Features Visit from FCPS Superintendent | Poster

    Cancer.gov

    One of the highlights of the 19th annual Spring Research Festival (SRF), held May 4–7, was a visit from Terry Alban, Ph.D., superintendent of Frederick County Public Schools (FCPS), and Mike Markoe, deputy superintendent, FCPS. They toured the event on May 7, talking to researchers and students about their posters. “Dr. Alban was very interested in hearing what the Werner H. Kirsten students were presenting at their posters,” said Andrea Frydl, public affairs specialist, Office of Scientific Operations, NCI at Frederick. “Many WHK students are also FCPS students, some of whom Dr. Alban and Dr. Markoe knew personally.” Alban tweeted (@FCPSMDSuper) photos and information about four of the students whose posters she visited during the tour.

  11. This Car Seems to Be Alive--Perspectives on the Documentary, "Plan F"

    ERIC Educational Resources Information Center

    Quinlan, Margaret M.; Smith, J. Webster; Hayward, Casey

    2009-01-01

    Ed Marko redefines what it means to be not only an auto mechanic but also a person who is blind. At the age of 20 years, he lost his sight from a degenerative disease called infantile glaucoma. However, he has surpassed what we traditionally think of as the capabilities of blind people. Now in his late 60s, he was once a rehabilitation counsellor,…

  12. Left-handed materials and negative refraction: Transfer matrix and FDTD calculations

    NASA Astrophysics Data System (ADS)

    Soukoulis, Costas M.

    2004-03-01

    We will present transfer matrix calculations of metallic wires, split ring resonators (SRR) and left-handed materials (LHM). Our results [1] show that the transfer matrix method can capture all the details characteristics of the metamaterials. In particular the dependence of the resonance frequency and its width on the structural parameters of the SRR and the size of the unit cell is studied. Also the dependence of the imaginary part of effective permittivity of arrays of metallic wires is studied in detail. It is found [2,3] that the imaginary part of effective permittivity has small values even for wires as small as 20 micron in diameter. The transfer matrix is very useful in calculating both the amplitude and the phase of the transmission and reflection coefficient. These numerical data was used [4] in the determination of the effective parameters of the metamaterials. It was indeed found that the refractive index was unambiguously negative in the frequency region where both ɛ and μ were negative. Finally, we will show that SRR have a strong electric response, equivalent to that of cut wires [5], which dominates the response of LHM. A new criterion is introduced to clearly identify if an experimental expression peak is left- or right handed. Finite difference time domain (FDTD) simulations will be presented for the transmission of the EM wave through the interface of the positive and negative refraction index. It is found [6] that the wave is trapped temporarily at the interface and after a long time the wave front moves eventually in the direction of negative refraction. The differences between negative refraction in photonic crystals and left-handed materials will be also discussed. Work supported by US-DOE, DARPA, NSF and EU (DALHM project). References: [1] P. Markos and C. M. Soukoulis, Phys. Rev. B 65, 033401 (2002); Phys. Rev. E 65, 036622 (2002). [2] P. Markos, I. Rousochatzakis and C. M. Soukoulis, Phys. Rev. B 66, 045601 (2002). [3] P. Markos and C. M

  13. Comment II on ``Resonant and antiresonant frequency dependence of the effective parameters of metamaterials''

    NASA Astrophysics Data System (ADS)

    Efros, A. L.

    2004-10-01

    In a recent paper,

    Koshny, Markos, Smith, and Soukoulis [Phys. Rev E 68, 065602 (2003)]
    report that their computations show that the product of imaginary parts of electric permittivity and magnetic permeability in a passive media is negative. They also criticize a well-known theorem that both imaginary parts are positive as a result of the second law of thermodynamics. I argue that this criticism has no ground and that computational evidence may result from inadequate introduction of the very concept of ɛ (ω) and μ (ω) in a photonic crystal.

  14. Using an effective dimensionality to map the force-extension relation for a semi-flexible polymer in a nanoslit

    NASA Astrophysics Data System (ADS)

    de Haan, Hendrick

    2015-03-01

    The force-extension relation for a semi-flexible polymer is well described by the Marko-Siggia equation in both two and three dimensions. However, while of interest for experimental systems such as DNA in nanopits, the behaviour between these limiting dimensionalities is less understood. I will present results from simulations of a polymer subject to a stretching force F confined in nanoslits of varying heights h. Going from the 3D case to the 2D case, both the coefficients of the equation and the relevant persistence length are shown to change. This observation leads to the definition of an effective dimensionality, deff, to characterize the system. At low F, using deff in a generalized form of the Marko-Siggia relation provides good agreement with the simulation curves. However, at high F, deff drifts back towards d = 3 . 0 . The reason behind this F dependence is discussed. Semi-empirical forms for strong and weak confinement regimes will be presented and shown to give good agreement across all slit heights and stretching forces. deff is thus dependent on h and F and provides a cohesive physical picture for all regimes.

  15. Expected geoneutrino signal at JUNO

    NASA Astrophysics Data System (ADS)

    Strati, Virginia; Baldoncini, Marica; Callegari, Ivan; Mantovani, Fabio; McDonough, William F.; Ricci, Barbara; Xhixha, Gerti

    2015-12-01

    Constraints on the Earth's composition and on its radiogenic energy budget come from the detection of geoneutrinos. The Kamioka Liquid scintillator Antineutrino Detector (KamLAND) and Borexino experiments recently reported the geoneutrino flux, which reflects the amount and distribution of U and Th inside the Earth. The Jiangmen Underground Neutrino Observatory (JUNO) neutrino experiment, designed as a 20 kton liquid scintillator detector, will be built in an underground laboratory in South China about 53 km from the Yangjiang and Taishan nuclear power plants, each one having a planned thermal power of approximately 18 GW. Given the large detector mass and the intense reactor antineutrino flux, JUNO aims not only to collect high statistics antineutrino signals from reactors but also to address the challenge of discriminating the geoneutrino signal from the reactor background. The predicted geoneutrino signal at JUNO is terrestrial neutrino unit (TNU), based on the existing reference Earth model, with the dominant source of uncertainty coming from the modeling of the compositional variability in the local upper crust that surrounds (out to approximately 500 km) the detector. A special focus is dedicated to the 6° × 4° local crust surrounding the detector which is estimated to contribute for the 44% of the signal. On the basis of a worldwide reference model for reactor antineutrinos, the ratio between reactor antineutrino and geoneutrino signals in the geoneutrino energy window is estimated to be 0.7 considering reactors operating in year 2013 and reaches a value of 8.9 by adding the contribution of the future nuclear power plants. In order to extract useful information about the mantle's composition, a refinement of the abundance and distribution of U and Th in the local crust is required, with particular attention to the geochemical characterization of the accessible upper crust where 47% of the expected geoneutrino signal originates and this region contributes

  16. Water quality and pollution status of Chambal river in National Chambal Sanctuary, Madhya Pradesh.

    PubMed

    Saksena, D N; Garg, R K; Rao, R J

    2008-09-01

    The physico-chemical characteristics of Chambal river water in National Chambal sanctuary (Madhya Pradesh) have been studied. The stretch of Chambal river contained in the National Chambal sanctuary (located at 25 degrees 23'-26 degrees 52'N, 76 degrees 28'-79 degrees 15'E) is extending up to 600 km downstream from Kota (Rajasthan) to the confluence of the Chambal with Yamuna river (Etawah). The river flow in Madhya Pradesh spans up to approximately 400 km. Three sampling stations viz., Station A--near Palighat, district Sheopurkalan, Station B--near Rajghat, district Morena and Station C--near Baraighat, district Bhind were established for the collection of water samples during April, 2003 to March, 2004. The water quality parameters namely transparency (12.12-110 cm), colour (transparent-very turbid), turbidity (1-178 TNU), electrical conductivity (145.60-884 microS cm(-1)), total dissolved solids (260-500 mgl(-1)), pH (7.60-9.33), dissolved oxygen (4.86-14.59 mgl(-1)), free carbon dioxide (0-16.5 mgl(-1)), total alkalinity (70-290 mgl(-1)), total hardness (42-140 mgl(-1)), chloride (15.62-80.94 mgl(-1)), nitrate (0.008-0.025 mgl(-1)), nitrite (0.002-0.022 mgl(-1)), sulphate (3.50-45 mgl(-1)), phosphate (0.004-0.050 mgl(-1)), silicate (2.80-13.80 mgl(-1)), biochemical oxygen demand (0.60-5.67 mgl(-1)), chemical oxygen demand (2.40-26.80 mgl(-1)), ammonia (nil-0.56 mgl(-1)), sodium (14.30-54.40 mgl(-1)) and potassium (2.10 mgl(-1)-6.30 mgl(-1)) reflects on the pristine nature of the river in National Chambal sanctuary. On the basis of various parameters studied, Chambal river in this stretch can be placed under the category of oligosaprobic. The water quality analysis, indicated that the riverwater in the sanctuary area is pollution free and can serve as a good habitat for many aquatic animals including endangered species. PMID:19295068

  17. Water quality and pollution status of Chambal river in National Chambal Sanctuary, Madhya Pradesh.

    PubMed

    Saksena, D N; Garg, R K; Rao, R J

    2008-09-01

    The physico-chemical characteristics of Chambal river water in National Chambal sanctuary (Madhya Pradesh) have been studied. The stretch of Chambal river contained in the National Chambal sanctuary (located at 25 degrees 23'-26 degrees 52'N, 76 degrees 28'-79 degrees 15'E) is extending up to 600 km downstream from Kota (Rajasthan) to the confluence of the Chambal with Yamuna river (Etawah). The river flow in Madhya Pradesh spans up to approximately 400 km. Three sampling stations viz., Station A--near Palighat, district Sheopurkalan, Station B--near Rajghat, district Morena and Station C--near Baraighat, district Bhind were established for the collection of water samples during April, 2003 to March, 2004. The water quality parameters namely transparency (12.12-110 cm), colour (transparent-very turbid), turbidity (1-178 TNU), electrical conductivity (145.60-884 microS cm(-1)), total dissolved solids (260-500 mgl(-1)), pH (7.60-9.33), dissolved oxygen (4.86-14.59 mgl(-1)), free carbon dioxide (0-16.5 mgl(-1)), total alkalinity (70-290 mgl(-1)), total hardness (42-140 mgl(-1)), chloride (15.62-80.94 mgl(-1)), nitrate (0.008-0.025 mgl(-1)), nitrite (0.002-0.022 mgl(-1)), sulphate (3.50-45 mgl(-1)), phosphate (0.004-0.050 mgl(-1)), silicate (2.80-13.80 mgl(-1)), biochemical oxygen demand (0.60-5.67 mgl(-1)), chemical oxygen demand (2.40-26.80 mgl(-1)), ammonia (nil-0.56 mgl(-1)), sodium (14.30-54.40 mgl(-1)) and potassium (2.10 mgl(-1)-6.30 mgl(-1)) reflects on the pristine nature of the river in National Chambal sanctuary. On the basis of various parameters studied, Chambal river in this stretch can be placed under the category of oligosaprobic. The water quality analysis, indicated that the riverwater in the sanctuary area is pollution free and can serve as a good habitat for many aquatic animals including endangered species.

  18. Polymer extension under flow: A path integral evaluation of the free energy change using the Jarzynski relation

    NASA Astrophysics Data System (ADS)

    Ghosal, Aishani; Cherayil, Binny J.

    2016-06-01

    The Jarzynski relation (and its variants) has provided a route to the experimental evaluation of equilibrium free energy changes based on measurements conducted under arbitrary non-equilibrium conditions. Schroeder and co-workers [Soft Matter 10, 2178 (2014) and J. Chem. Phys. 141, 174903 (2014)] have recently exploited this fact to determine the elastic properties of model DNA from simulations and experiments of chain extension under elongational flow, bypassing the need to make these measurements mechanically using sophisticated optical trapping techniques. In this paper, motivated by these observations, we investigate chain elasticity analytically, using the Jarzynski relation and a finitely extensible nonlinear elastic-type Rouse model within a path integral formalism to calculate (essentially exactly) both the flow-induced free energy change between chain conformations of definite average end-to-end distance, as well as the force-extension curve that follows from it. This curve, based on a new analytic expression, matches the trends in the corresponding curve obtained from a model of chain stretching developed by Marko and Siggia [Macromolecules 28, 8759 (1995)], which itself is in very satisfactory agreement with the numerical and experimental data from the work of Schroeder et al.

  19. Microelasticity of Single Mitotic Chromosomes

    NASA Astrophysics Data System (ADS)

    Poirier, Michael; Eroglu, Sertac; Chatenay, Didier; Marko, John F.; Hirano, Tatsuya

    2000-03-01

    The force-extension behavior of mitotic chromosomes from the newt TVI tumor cell line was studied using micropipette manipulation and force measuring techniques. Reversible, linear elastic response was observed for extensions up to 5 times the native length; the force required to double chromosome length was 1 nanonewton (nN). For further elongations, the linear response teminates at a force plateau of 15 nN and at an extension of 20x. Beyond this extension, the chromosome breaks at elongations between 20x and 70x. These results will be compared to the similar behavior of mitotic chromosomes from explanted newt cells (Poirier, Eroglu, Chatenay and Marko, Mol. Biol. Cell, in press). Also, the effect of biochemical modifications on the elasticity was studied. Ethidium Bromide, which binds to DNA, induces up to a 10 times increase in the Young's modulus. Anti-XCAP-E, which binds to a putative chromosome folding protein, induces up to a 2 times increase in the Young's modulus. Preliminary results on the dynamical relaxation of chromosomes will also be presented. Support of this research through a Biomedical Engineering Research Grant from The Whitaker Foundation is gratefully acknowledged.

  20. Polymer extension under flow: A path integral evaluation of the free energy change using the Jarzynski relation.

    PubMed

    Ghosal, Aishani; Cherayil, Binny J

    2016-06-01

    The Jarzynski relation (and its variants) has provided a route to the experimental evaluation of equilibrium free energy changes based on measurements conducted under arbitrary non-equilibrium conditions. Schroeder and co-workers [Soft Matter 10, 2178 (2014) and J. Chem. Phys. 141, 174903 (2014)] have recently exploited this fact to determine the elastic properties of model DNA from simulations and experiments of chain extension under elongational flow, bypassing the need to make these measurements mechanically using sophisticated optical trapping techniques. In this paper, motivated by these observations, we investigate chain elasticity analytically, using the Jarzynski relation and a finitely extensible nonlinear elastic-type Rouse model within a path integral formalism to calculate (essentially exactly) both the flow-induced free energy change between chain conformations of definite average end-to-end distance, as well as the force-extension curve that follows from it. This curve, based on a new analytic expression, matches the trends in the corresponding curve obtained from a model of chain stretching developed by Marko and Siggia [Macromolecules 28, 8759 (1995)], which itself is in very satisfactory agreement with the numerical and experimental data from the work of Schroeder et al. PMID:27276965

  1. Advanced powder metallurgy aluminum alloys via rapid solidification technology, phase 2

    NASA Technical Reports Server (NTRS)

    Ray, Ranjan; Jha, Sunil C.

    1987-01-01

    Marko's rapid solidification technology was applied to processing high strength aluminum alloys. Four classes of alloys, namely, Al-Li based (class 1), 2124 type (class 2), high temperature Al-Fe-Mo (class 3), and PM X7091 type (class 4) alloy, were produced as melt-spun ribbons. The ribbons were pulverized, cold compacted, hot-degassed, and consolidated through single or double stage extrusion. The mechanical properties of all four classes of alloys were measured at room and elevated temperatures and their microstructures were investigated optically and through electron microscopy. The microstructure of class 1 Al-Li-Mg alloy was predominantly unrecrystallized due to Zr addition. Yield strengths to the order of 50 Ksi were obtained, but tensile elongation in most cases remained below 2 percent. The class 2 alloys were modified composition of 2124 aluminum alloy, through addition of 0.6 weight percent Zr and 1 weight percent Ni. Nickel addition gave rise to a fine dispersion of intermetallic particles resisting coarsening during elevated temperature exposure. The class 2 alloy showed good combination of tensile strength and ductility and retained high strength after 1000 hour exposure at 177 C. The class 3 Al-Fe-Mo alloy showed high strength and good ductility both at room and high temperatures. The yield and tensile strength of class 4 alloy exceeded those of the commercial 7075 aluminum alloy.

  2. Theory for the hydrodynamic and electrophoretic stretch of tethered B-DNA.

    PubMed Central

    Stigter, D; Bustamante, C

    1998-01-01

    We have developed a theory for the extension and force of B-DNA tethered at a fixed point in a uniform hydrodynamic flow or in a uniform applied electric field. The chain tethered in an electric field is considered to be subject to free electrophoresis compensated by free sedimentation in the opposite direction. This allows the use of results of free electrophoresis for including the effects of small ions. The force on the chain is derived for a sequence of ellipsoidal segments, each twice the persistence length of the wormlike chain. Hydrodynamic interaction between these segments is based on the long-range limit of flow around the prolate ellipsoids, as derived from equivalent Stokes spheres. The chain extension is derived by applying the entropic elasticity relation of Marko and Siggia (1995 Macromolecules. 28:8759-8770) to each segment for polymer chains under constant tension. We justify this procedure by comparing with extension results based on the Boltzmann averaged orientation of straight, freely jointed segments. Predicted results agree well with recent extension-flow experiments by Perkins et al., 1995. Science. 258:83-87, and with electrophoretic stretch experiments by Smith and Bendich (1990 Biopolymers. 29:1167-1173) on fluorescently stained B-DNA. We find that the equivalence of hydrodynamic and electrophoretic stretch, proposed by Long et al. (1996 Phys. Rev. Lett. 76:3858-3861; 1996 Biopolymers 39:755-759), is valid only for very small chain deformations, but not in general. PMID:9726922

  3. Lost in the Dark: A proto-history of dark matter

    NASA Astrophysics Data System (ADS)

    Trimble, Virginia L.; History 1

    2016-01-01

    Einasto, Kaasik, and Saar (published in Nature, in case you are thinking of more Meddelande). I feel enormous respect and affection for Vera Rubin and Fritz Zwicky, but the published papers as are they are.

  4. Rate of recovery of Mycobacterium tuberculosis from frozen acid-fast-bacillus smear-positive sputum samples subjected to long-term storage in Northwest Ethiopia.

    PubMed

    Tessema, Belay; Beer, Joerg; Emmrich, Frank; Sack, Ulrich; Rodloff, Arne C

    2011-07-01

    Tuberculosis is a major public health problem in Ethiopia. The diagnosis and treatment of drug-resistant tuberculosis remain a challenge in the country. This study aimed to assess whether single morning sputum samples could be stored at -20 °C for extended periods of time at remote settings and then transported and successfully cultured for Mycobacterium tuberculosis. Single morning sputum samples were collected from all smear-positive tuberculosis patients diagnosed at Gondar Hospital, Gondar Health Center, Metemma Hospital, Bahir Dar Hospital, and Debre Markos Hospital in Northwest Ethiopia between March and July 2009. Specimens were stored at the study sites and sent to the mycobacteriology laboratory at the University Hospital, Leipzig, Germany, where specimens were processed and inoculated into the BacT/Alert 3D system and Lowenstein-Jensen and Gottsacker media. Ice packs were added in the package of the specimens during transport. A total of 319 patients were enrolled in this study. The median specimen storage time was 132 days (range, 16 to 180 days). Of all specimens, 283 (88.7%) were culture positive by any of the three culturing systems. M. tuberculosis isolates from four contaminated specimens in all culturing systems were successfully isolated on Middlebrook 7H10 agar; thereby, the recovery rate increased to 287 (90.0%). The length of time of sputum storage had no significant effect on the rate of recovery of M. tuberculosis in all culturing systems. In conclusion, single morning sputum specimens collected at remote settings stored at -20 °C for long periods of time without the addition of preservatives can yield a high recovery rate. These findings suggest a simple and cost-effective alternative method of sputum storage for epidemiological and drug resistance studies in low-resource countries. PMID:21562105

  5. Prediction of sea ice thickness cluster in the Northern Hemisphere

    NASA Astrophysics Data System (ADS)

    Fuckar, Neven-Stjepan; Guemas, Virginie; Johnson, Nathaniel; Doblas-Reyes, Francisco

    2016-04-01

    Sea ice thickness (SIT) has a potential to contain substantial climate memory and predictability in the northern hemisphere (NH) sea ice system. We use 5-member NH SIT, reconstructed with an ocean-sea-ice general circulation model (NEMOv3.3 with LIM2) with a simple data assimilation routine, to determine NH SIT modes of variability disentangled from the long-term climate change. Specifically, we apply the K-means cluster analysis - one of nonhierarchical clustering methods that partition data into modes or clusters based on their distances in the physical - to determine optimal number of NH SIT clusters (K=3) and their historical variability. To examine prediction skill of NH SIT clusters in EC-Earth2.3, a state-of-the-art coupled climate forecast system, we use 5-member ocean and sea ice initial conditions (IC) from the same ocean-sea-ice historical reconstruction and atmospheric IC from ERA-Interim reanalysis. We focus on May 1st and Nov 1st start dates from 1979 to 2010. Common skill metrics of probability forecast, such as rank probability skill core and ROC (relative operating characteristics - hit rate versus false alarm rate) and reliability diagrams show that our dynamical model predominately perform better than the 1st order Marko chain forecast (that beats climatological forecast) over the first forecast year. On average May 1st start dates initially have lower skill than Nov 1st start dates, but their skill is degraded at slower rate than skill of forecast started on Nov 1st.

  6. Rate of Recovery of Mycobacterium tuberculosis from Frozen Acid-Fast-Bacillus Smear-Positive Sputum Samples Subjected to Long-Term Storage in Northwest Ethiopia ▿

    PubMed Central

    Tessema, Belay; Beer, Joerg; Emmrich, Frank; Sack, Ulrich; Rodloff, Arne C.

    2011-01-01

    Tuberculosis is a major public health problem in Ethiopia. The diagnosis and treatment of drug-resistant tuberculosis remain a challenge in the country. This study aimed to assess whether single morning sputum samples could be stored at −20°C for extended periods of time at remote settings and then transported and successfully cultured for Mycobacterium tuberculosis. Single morning sputum samples were collected from all smear-positive tuberculosis patients diagnosed at Gondar Hospital, Gondar Health Center, Metemma Hospital, Bahir Dar Hospital, and Debre Markos Hospital in Northwest Ethiopia between March and July 2009. Specimens were stored at the study sites and sent to the mycobacteriology laboratory at the University Hospital, Leipzig, Germany, where specimens were processed and inoculated into the BacT/Alert 3D system and Lowenstein-Jensen and Gottsacker media. Ice packs were added in the package of the specimens during transport. A total of 319 patients were enrolled in this study. The median specimen storage time was 132 days (range, 16 to 180 days). Of all specimens, 283 (88.7%) were culture positive by any of the three culturing systems. M. tuberculosis isolates from four contaminated specimens in all culturing systems were successfully isolated on Middlebrook 7H10 agar; thereby, the recovery rate increased to 287 (90.0%). The length of time of sputum storage had no significant effect on the rate of recovery of M. tuberculosis in all culturing systems. In conclusion, single morning sputum specimens collected at remote settings stored at −20°C for long periods of time without the addition of preservatives can yield a high recovery rate. These findings suggest a simple and cost-effective alternative method of sputum storage for epidemiological and drug resistance studies in low-resource countries. PMID:21562105

  7. Network model of human language

    NASA Astrophysics Data System (ADS)

    Markošová, Mária

    2008-01-01

    The phenomenon of human language is widely studied from various points of view. It is interesting not only for social scientists, antropologists or philosophers, but also for those, interested in the network dynamics. In several recent papers word web, or language as a graph has been investigated [R.F. Cancho, R. Solé, The small world of human language, Proc. R. Soc. London B 268 (2001) 2261-2265; A.E. Motter, P.S. de Moura, Lai Ying-Cheng, P. Dasgupta, Topology of the conceptual network of language, Phys. Rev. E 65 (2002) R 065102; M. Steyvers, J.B. Tenenbaum, The large-scale structure of semantic networks: Statistical analysis and a model of semantic growth, Cogn. Sci. 29 (2005) 41-78]. In this paper I revise recent studies of syntactical word web [R.F. Cancho, R. Solé, The small world of human language, Proc. R. Soc. London B 268 (2001) 2261-2265; S.N. Dorogovtsev, J.F.F. Mendes, Language as an evolving word web, Proc. R. Soc. London B 268 (2001) 2603-2606]. I present a model of growing network in which such processes as node addition, edge rewiring and new link creation are taken into account. I argue, that this model is a satisfactory minimal model explaining measured data [R.F. Cancho, R. Solé, The small world of human language, Proc. R. Soc. London B 268 (2001) 2261-2265; M. Markošová, P. Náther, Language as a graph, in: V. Kvasnička, P. Trebatický, J. Pospíchal (Eds.), Mind, Intelligence and Life, Kelemen, STU Bratislava, 2007, pp. 298-307 (in Slovak)].

  8. Toward efficient fiber-based quantum interface (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Soshenko, Vladimir; Vorobyov, Vadim V.; Bolshedvorsky, Stepan; Lebedev, Nikolay; Akimov, Alexey V.; Sorokin, Vadim; Smolyaninov, Andrey

    2016-04-01

    , vol. 528, no. 1, p. 1-45, 2013. [2] A.V. Akimov, A. Mukherjee, C.L. Yu, D.E. Chang, A.S. Zibrov, P.R. Hemmer, H. Park and M.D. Lukin, "Generation of single optical plasmons in metallic nanowires coupled to quantum dots," Nature, vol. 450, p. 402-406, 2007. [3] Michael J. Burek , Yiwen Chu, Madelaine S.Z. Liddy, Parth Patel, Jake Rochman , Srujan Meesala, Wooyoung Hong, Qimin Quan, Mikhail D. Lukin and Marko Loncar High quality-factor optical nanocavities in bulk single-crystal diamond, Nature communications 6718 (2014) [4] Tim Schroder, Andreas W. Schell, Gunter Kewes, Thomas Aichele, and Oliver Benson Fiber-Integrated Diamond-Based Single Photon Source, Nano Lett. 2011, 11, 198-202 [5]Lars Liebermeister, et. al. "Tapered fiber coupling of single photons emitted by a deterministically positioned single nitrogen vacancy center", Appl. Phys. Lett. 104, 031101 (2014)

  9. Catalytic Deprotection of Acetals In Strongly Basic Solution Usinga Self-Assembled Supramolecular 'Nanozyme'

    SciTech Connect

    Pluth, Michael D.; Bergman, Robert G.; Raymond, Kenneth N.

    2007-07-26

    Acetals are among the most commonly used protecting groups for aldehydes and ketones in organic synthesis due to their ease of installation and resistance to cleavage in neutral or basic solution.[1] The common methods for hydrolyzing acetals almost always involve the use of either Broensted acid or Lewis acid catalysts.[2] Usually aqueous acids or organic solutions acidified with organic or inorganic acids have been used for reconversion of the acetal functionality to the corresponding carbonyl group; however, recently a number of reports have documented a variety of strategies for acetal cleavage under mild conditions. These include the use of Lewis acids such as bismuth(III)[3] or cerium(IV),[4, 5] functionalized silica gel, such as silica sulfuric acid[6] or silica-supported pyridinium p-toluene sulfonate,[7] or the use of silicon-based reagents such as TESOTf-2,6-Lutidine.[8] Despite these mild reagents, all of the above conditions require either added acid or overall acidic media. Marko and co-workers recently reported the first example of acetal deprotection under mildly basic conditions using catalytic cerium ammonium nitrate at pH 8 in a water-acetonitrile solution.[5] Also recently, Rao and co-workers described a purely aqueous system at neutral pH for the deprotection of acetals using {beta}-cyclodextrin as the catalyst.[9] Herein, we report the hydrolysis of acetals in strongly basic aqueous solution using a self-assembled supramolecular host as the catalyst. During the last decade, we have used metal-ligand interactions for the formation of well-defined supramolecular assemblies with the stoichiometry M{sub 4}L{sub 6}6 (M = Ga{sup III} (1 refers to K{sub 12}[Ga{sub 4}L{sub 6}]), Al{sup III}, In{sup III}, Fe{sup III}, Ti{sup IV}, or Ge{sup IV}, L = N,N{prime}-bis(2,3-dihydroxybenzoyl)-1,5-diaminonaphthalene) (Figure 1).[10] The metal ions occupy the vertices of the tetrahedron and the bisbidentate catecholamide ligands span the edges. The strong

  10. PREFACE: The Universe under the Microscope: Astrophysics at High Angular Resolution

    NASA Astrophysics Data System (ADS)

    Schödel, Rainer

    2009-01-01

    Köln, Köln, Germany Eduardo Ros Max-Planck-Institut für extraterrestrische Physik, Bonn, Germany Scientific organizing committee Dennis Downes Institut de Radio Astronomie Millimétrique, France Wolfgang Duschl University of Kiel, Germany Andrea Ghez University of California, Los Angeles, USA Vladimir Karas Academy of Sciences, Czech Republic Andreas Eckart University of Cologne, Germany Sera Marko University of Amsterdam, The Netherlands Susanne Pfalzner University of Cologne, Germany Sebastian Rabien Max-Planck-Institute for Extraterrestrial Physics, Germany Daniel Rouan Observatoire de Paris-Meudon, France Eduardo Ros Max-Planck-Institute for Radio Astronomy, Germany Rainer Schödel Instituto de Astrofísica de Andalucía -CSIC, Spain Zhiqiang Shen Shanghai Astronomical Observatory, China Anton Zensus Max-Planck-Institute for Radio Astronomy, Germany Local organizing committee Sebastian Fischer University of Cologne, Germany Devaky Kunneriath University of Cologne, Germany Leo Meyer University of Cologne, Germany Koraljka Muzic University of Cologne, Germany Rainer Schödel University of Cologne, Germany/IAA -CSIC, Spain Christian Straubmeier University of Cologne, Germany Mohammad Zamaninasab University of Cologne, Germany

  11. EDITORIAL: Focus on Cold and Ultracold Molecules FOCUS ON COLD AND ULTRACOLD MOLECULES

    NASA Astrophysics Data System (ADS)

    Carr, Lincoln D.; Ye, Jun

    2009-05-01

    öhlich, A Griesmaier, T Pfau, H Saito, Y Kawaguchi and M Ueda High-energy-resolution molecular beams for cold collision studies L P Parazzoli, N Fitch, D S Lobser and H J Lewandowski Collisional effects in the formation of cold guided beams of polar molecules M Motsch, C Sommer, M Zeppenfeld, L D van Buuren, P W H Pinkse and G Rempe Towards sympathetic cooling of large molecules: cold collisions between benzene and rare gas atoms P Barletta, J Tennyson and P F Barker Efficient formation of ground-state ultracold molecules via STIRAP from the continuum at a Feshbach resonance Elena Kuznetsova, Marko Gacesa, Philippe Pellegrini, Susanne F Yelin and Robin Côté Emergent timescales in entangled quantum dynamics of ultracold molecules in optical lattices M L Wall and L D Carr Rotational state resolved photodissociation spectroscopy of translationally and vibrationally cold MgH+ ions: toward rotational cooling of molecular ions K Højbjerre, A K Hansen, P S Skyt, P F Staanum and M Drewsen Collective transverse cavity cooling of a dense molecular beam Thomas Salzburger and Helmut Ritsch A Stark decelerator on a chip Samuel A Meek, Horst Conrad and Gerard Meijer Deceleration of molecules by dipole force potential: a numerical simulation Susumu Kuma and Takamasa Momose Ultracold molecules: vehicles to scalable quantum information processing Kathy-Anne Brickman Soderberg, Nathan Gemelke and Cheng Chin Magnetic field modification of ultracold molecule-molecule collisions T V Tscherbul, Yu V Suleimanov, V Aquilanti and R V Krems Spectroscopy of 39K85Rb triplet excited states using ultracold a 3Σ+ state molecules formed by photoassociation J T Kim, D Wang, E E Eyler, P L Gould and W C Stwalley Pumping vortex into a Bose-Einstein condensate of heteronuclear molecules Z F Xu, R Q Wang and L You Intense atomic and molecular beams via neon buffer-gas cooling David Patterson, Julia Rasmussen and John M Doyle Dynamical properties of dipolar Fermi gases T Sogo, L He, T Miyakawa, S Yi, H Lu

  12. Poster Session C

    PubMed Central

    2014-01-01

    , Cambridge, MA, USA; 3Howard Hughes Medical Institute Massachussets General Hospital, Boston, MA, USA A challenge to obtaining high quality organellar proteomes is the difficulty of purifying organelles to homogeneity without loss of crucial components. Furthermore, many subcellular regions of great importance cannot be purified at all, and hence their proteomes are not known. We present a live cell proximity-dependent enzymatic biotinylation strategy that bypasses the need for organellar purification and produces highly specific proteomic maps of multiple subcellular regions. The tagging enzyme is APEX2, an evolved variant of soybean ascorbate peroxidase that generates short-lived biotin-phenoxyl radicals for covalent tagging in vivo. We used this approach to generate proteomes of 137 and 637 proteins, respectively, for the outer mitochondrial membrane and endoplasmic reticulum membranes. Our list contains numerous novel proteins not previously associated with these cellular regions that potentially point to novel biological functions. C.8 Optimization of Glycopeptide Enrichment Using Lectin Weak Affinity Chromatography Jason Maynard, Krista Kaasik, A.L. Burlingame Department of Pharmaceutical Chemistry, School of, San Francisco, CA, USA O-linked N-acetylglucosamine (O-GlcNAc) modification of serine and threonine residues in cytosolic and nuclear proteins has been implicated in diverse molecular processes within the cell from regulation of the cell cycle to synaptic plasticity. Cellular levels of O-GlcNAc are sensitive to a number of nutrients including glucose and glutamine. Misregulation of O-GlcNAc has also been implicated in several human diseases, including diabetes, cardiac infarction, and neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. Although ubiquitous within the cell and discovered over thirty years ago, large-scale studies of O-GlcNAc have lagged far behind those of other post-translational modifications, including phosphorylation

  13. Poster Session B

    PubMed Central

    2014-01-01

    proteins which are fundamental regulators of PPARg and the fat cell commitment decision. B.6 Application of Quantitative and Functional Phosphoproteomics In Study of Ethylene Signaling Ning Li 1 1The Hong Kong University of Science and Technology, Hong Kong, China Ethylene is a major plant hormone that regulates a diverse aspect of plant growth and development. The regulatory roles of ethylene in plants include promotion of leaf and flower petal senescence, yellowing and abscission, as well as promotion of fruit abscission and ripening. This key hormone is also involved in regulation of a number of plant biotic and abiotic stress responses. A dramatic effect of ethylene on tropic response is the dual-and-opposing effect of ethylene on stem negative gravitropic response, in which short-term ethylene treatment (0.5 hour) appears to inhibit stem bending up following re-orientation of inflorescence of Arabidopsis. In contrast, a long-term treatment (12 hours) stimulates gravitropic response and promote stem curve up faster. This time-dependent and dose- independent dual-and-opposing effect of ethylene on stem gravitropism may involve multiple signaling pathways. Stable isotope metabolic labeling-based quantitative phosphoproteomics performed on ein2–5, ctr1–1 and rcn1–1 ethylene signaling mutants indeed confirmed the time-dependent protein phosphorylation changes and some of phosphorylation events are independent to ein2 loss-of- function gene in response to ethylene treatment. Functional studies on the phosphorylated transcription factor ERF110 isoform suggest that it is required for the control of flowering time via multiple ethylene signaling pathways. B.7 Intact N- and O-linked Glycopeptide Identification from HCD Data Using Byonic Katalin F. Medzihradszky1, Jason Maynard1, Krista Kaasik1, Marshall Bern2 1University of California, San Francisco, CA, USA; 2Protein Metrics, San Carlos, CA, USA The importance of high quality analysis of glycosylated proteins is steadily