992 resultados para 107-656A


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The material presented in this paper summarizes the progress that has been made in the analysis, design, and testing of concrete structures. The material is summarized in the following documents: 1. Part I - Containment Design Criteria and Loading Combinations - J.D. Stevenson (Stevenson and Associates, Cleveland, Ohio, USA) 2. Part II - Reinforced and Prestressed Concrete Behavior - J. Eibl and M. Curbach (Karlsruhe University, Karlsruhe, Germany) 3. Part III - Concrete Containment Analysis, Design and Related Testing - T.E. Johnson and M.A. Daye (Bechtel Power Corporation, Gaithersburg, Maryland USA) 4. Part IV - Impact and Impulse Loading and Response Prediction - J.D. Riera (School of Engineering - UFRGS, Porto Alegre, RS, Brazil) 5. Part V - Metal Containments and Liner Plate Systems - N.J. Krutzik (Siemens AG, Offenbach Am Main, Germany) 6. Part VI - Prestressed Reactor Vessel Design, Testing and Analysis - J. Nemet (Austrian Research Center, Seibersdorf, Austria) and K.T.S. Iyengar (Indian Institute of Science, Bangalore, India).

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In Taita Hills, south-eastern Kenya, remnants of indigenous mountain rainforests play a crucial role as water towers and socio-cultural sites. They are pressurized due to poverty, shortage of cultivable land and the fading of traditional knowledge. This study examines the traditional ecological knowledge of Taitas and the ways it may be applied within transforming natural resource management regimes. I have analyzed some justifications for and hindrances to ethnodevelopment and participatory forest management in light of recently renewed Kenyan forest policies. Mixed methods were applied by combining an ethnographic approach with participatory GIS. I learned about traditionally protected forests and their ecological and cultural status through a seek out the expert method and with remote sensing data and tools. My informants were: 107 household interviewees, 257 focus group participants, 73 key informants and 87 common informants in participatory mapping. Religious leaders and state officials shared their knowledge for this study. I have gained a better understanding of the traditionally protected forests and sites through examining their ecological characteristics and relation to social dynamics, by evaluating their strengths and hindrances as sites for conservation of cultural and biological diversity. My results show that, these sites are important components of a complex socio-ecological system, which has symbolical status and sacred and mystical elements within it, that contributes to the connectivity of remnant forests in the agroforestry dominated landscape. Altogether, 255 plant species and 220 uses were recognized by the tradition experts, whereas 161 species with 108 beneficial uses were listed by farmers. Out of the traditionally protected forests studied 47 % were on private land and 23% on community land, leaving 9% within state forest reserves. A paradigm shift in conservation is needed; the conservation area approach is not functional for private lands or areas trusted upon communities. The role of traditionally protected forests in community-based forest management is, however, paradoxal, since communal approaches suggests equal participation of people, whereas management of these sites has traditionally been the duty of solely accredited experts in the village. As modernization has gathered pace such experts have become fewer. Sacredness clearly contributes but, it does not equal conservation. Various social, political and economic arrangements further affect the integrity of traditionally protected forests and sites, control of witchcraft being one of them. My results suggest that the Taita have a rich traditional ecological knowledge base, which should be more determinately integrated into the natural resource management planning processes.

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A protein which binds specifically to [3H]-zeatin has been isolated from cucumber cotyledons by chromatographic techniques. Its binding to [3H]-zeatin was inhibited remarkably by the addition of non-radioactive cytokinins and the order of inhibition was zeatin > -zeatin riboside > N6-(Delta2-isopentenyl)adenine > N6-(Delta2-isopentenyl)adenosine > N6-benzyl-adenosine > kinetin riboside. This protein behaved as a soluble protein with an apparent molecular size of 43,000 daltons on gel filtration through calibrated Sephadex G-100 column. The dissociation constant, Kd, of the protein-zeatin complex was about 4 × 10–7 M.

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The expression of cytochrome P-450 (b+e) and glutathione transferase (Ya+Yc) genes has been studied as a function of development in rat liver. The levels of cytochrome P-450 (b+e) mRNAs and their transcription rates are too low for detection in the 19-day old fetal liver before or after phenobarbitone treatment. However, glutathione transferase (Ya+Yc) mRNAs can be detected in the fetal liver as well as their induction after phenobarbitone treatment can be demonstrated. These mRNAs contents as well as their inducibility with phenobarbitone are lower in maternal liver than that of adult nonpregnant female rat liver. Steroid hormone administration to immature rats blocks substantially the phenobarbitone mediated induction of the two mRNA families as well as their transcription. It is suggested that steroid hormones constitute one of the factors responsible for the repression of the cytochrome P-450 (b+e) and glutathione transferase (Ya+Yc) genes in fetal liver.

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A method for mass production of rosewood (Dalbergia latifolia Roxb.) trees through leaf disc organogenesis was developed and standardized. Compact callus was initiated from mature leaf discs on Murashige and Skoog (MS) basal medium supplemented with 1.0 mg 1?1 2,4-dichlorophenoxy acetic acid (2,4-D), 5.0 mg 1?1 ?-naphthaleneacetic acid (NAA), 1.0 mg 1?1 6-benzylaminopurine (BAP) and 10% coconut water (CW). High frequency (15�20 shoots/g callus) regeneration of shoot bud differentiation was obtained on MS (3/4 reduced major elements) or Woody Plant Medium (WPM) or modified Woody Plant Medium (mWPM) supplemented with BAP (5.0 mg 1?1) and NAA (0.5 mg 1?1). Leaf abscission and shoot tip necrosis was controlled using mWPM. About 90% of the excised shoots were rooted in the mWPM supplemented with 2.0 mg 1?1 ?-indolebutyric acid (IBA) and 1.0 mg 1?1 caffeic acid. The in vitro-raised rooted plantlets were hardened for successful transplantation to soil. The transplanted plants were exposed to various humidity conditions and 80% transplant success was achieved. The in vitro-raised leaf-regenerated plants grew normally and vigorously in soil.

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The granular flow down an inclined plane is simulated using the discrete element (DE) technique to examine the extent to which the dynamics of an unconfined dense granular flow can be well described by a hard particle model First, we examine the average coordination number for the particles in the flow down an inclined plane using the DE technique using the linear contact model with and without friction, and the Hertzian contact model with friction The simulations show that the average coordination number decreases below 1 for values of the spring stiffness corresponding to real materials, such as sand and glass, even when the angle of inclination is only 10 larger than the angle of repose Additional measures of correlations in the system, such as the fraction of particles with multibody contact, the force ratio (average ratio of the magnitudes of the largest and the second largest force on a particle), and the angle between the two largest forces on the particle, show no evidence of force chains or other correlated motions in the system An analysis of the bond-orientational order parameter indicates that the flow is in the random state, as in event-driven (ED) simulations V Kumaran, J Fluid Mech 632, 107 (2009), J Fluid Mech 632, 145 (2009)] The results of the two simulation techniques for the Bagnold coefficients (ratio of stress and square of the strain rate) and the granular temperature (mean square of the fluctuating velocity) are compared with the theory V Kumaran, J Fluid Mech 632, 107 (2009), J Fluid Mech 632, 145 (2009)] and are found to be in quantitative agreement In addition, we also conduct a comparison of the collision frequency and the distribution of the precollisional relative velocities of particles in contact The strong correlation effects exhibited by these two quantities in event-driven simulations V Kumaran, J Fluid Mech 632, 145 (2009)] are also found in the DE simulations (C) 2010 American Institute of Physics doi 10 1063/1 3504660]

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Lääkekustannukset kasvoivat 2000-luvulla useimmissa teollistuneissa maissa terveydenhuollon kokonaismenoja nopeammin. Lääkkeiden rahoituksesta vastaavat ovatkin etsineet keinoja kustannusten kasvun hillitsemiseksi. Uudet, vanhoja lääkkeitä kalliimmat lääkkeet ovat yksi syy kustannusten kasvuun. Tämän tutkimuksen tarkoitus oli selvittää uusien, avohoidossa käytettävien lääkkeiden käyttöönottoa, hintoja ja kustannuksia sekä analysoida lääkkeen erityiskorvattavuutta edeltävän peruskorvattavuusjakson ja korvauksen rajoittamisen vaikutuksia lääkkeiden kulutukseen ja hoitojen kohdentumiseen. Tutkimusten aineistoina käytettiin muun muassa Lääkelaitoksen ja Kelan tietokantoja ja lääkkeiden tukkumyyntitietoja. Lääkkeiden hintatiedot Euroopan maista kerättiin kyselyllä. Suomen markkinoille tuli vuosina 1996–2005 lähes 300 uutta lääkeainetta. Vuonna 2005 niiden osuus avohoidon lääkemyynnin arvosta oli 38 % ja kulutuksesta 19 %. Avohoidossa uutuuksia tuli erityisesti syöpien, infektioiden ja sydän- ja verisuonisairauksien hoitoon. Osa uutuuksista tarjosi merkittäviä uusia hoitomahdollisuuksia, osan lisähyöty oli vähäinen. Tiukan hintasääntelyn maissa uusien lääkkeiden tukkuhinnat olivat alhaisemmat kuin niissä maissa, joissa ei ollut suoraa sääntelyä. Maan asema tukkuhintojen vertailussa ei kuitenkaan määrittänyt sen asemaa vähittäismyyntihintaisessa vertailussa, sillä apteekkien kate ja verot vaihtelevat maittain. Suomessa uusien lääkkeiden tukkuhinnat olivat eurooppalaista keskitasoa, mutta verolliset vähittäismyyntihinnat keskitasoa korkeammat. Glaukooma-lääkkeillä erityiskorvattavuutta edeltävä peruskorvattavuusjakso hidasti uusien valmisteiden käyttöönottoa. Lääkkeiden tultua erityiskorvattaviksi niiden käyttäjämäärä ja kulutus kasvoivat. Kalleimpien statiinien korvauksen rajoittaminen niille potilaille, joille edullisemmat eivät sovi, lisäsi edullisten statiinien käyttöä. Rajoituksen jälkeen kalleimmat statiinit kanavoituivat sairaammille ja aiemmin muita statiineja käyttäneille. Toimenpiteiden pitkäaikaisvaikutuksista ja terveysvaikutuksista ei ole tietoa.

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Kinetic data on inhibition of protein synthesis in thymocyte by three abrins and ricin have been obtained. The intrinsic efficiencies of A chains of four toxins to inactivate ribosomes, as analyzed by k1-versus-concentration plots were abrin II, III > ricin > abrin I. The lag times were 90, 66, 75 and 105 min at a 0.0744 nM concentration of each of abrin I, II, III and ricin, respectively. To account for the observed differences in the dose-dependent lag time, functional and structural variables of toxins such as binding efficiency of B chains to receptors and low-pH-induced structural alterations have been analyzed. The association constants obtained by stopped flow studies showed that abrin-I (4.13 × 105 M−1 s−1) association with putative receptor (4-methylumbelliferyl-α-D-galactoside) is nearly two times more often than abrin III (2.6 × 105 M−1 s−1) at 20°C. Equillibrium binding constants of abrin I and II to thymocyte at 37°C were 2.26 × 107 M−1 and 2.8 × 107 M−1 respectively. pH-induced structural alterations as studied by a parallel enhancement in 8-anilino-L-naphthalene sulfonate fluorescence revealed a high degree of qualitative similarity. These results taken with a nearly identical concentration-independent lag time (minimum lag of 41–42 min) indicated that the binding efficiencies and internalization efficiencies of these toxins are the same and that the observed difference in the dose-dependent lag time is causally related to the proposed processing event. The rates of reduction of inter-subunit disulfide bond, an obligatory step in the intoxication process, have been measured and compared under a variety of conditions. Intersubunit disulfide reduction of abrin I is fourfold faster than that of abrin II at pH 7.2. The rate of disulfide reduction in abrin I could be decreased 1 I-fold by adding lactose, compared to that without lactose. The observed differences in the efficiencies of A chains, the dose-dependent lag period, the modulating effect of lactose on the rates of disulfide reduction and similarity in binding properties make the variants a valuable tool to probe the processing events in toxin transport in detail.

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NMR spectra of cis,cis-mucanonitrile oriented in a liquid crystal have been analysed using the connectivity information obtained from a modified Z-COSY experiment which provided crucial clues for the starting parameters for the iterative analysis. The proton spectra with and without C-13 satellites and the C-13 spectra have thus been interpreted. The indirect spin-spin couplings required for the analyses have been obtained from the corresponding isotropic spectra. The H-1-H-1 and C-13-H-1 dipolar couplings so obtained have been utilized to determine the relative internuclear distances. The results indicate that the molecule is planar. (C) 1994 Academic Press, Inc.

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Vaccines against Neisseria meningitidis group C are based on its alpha-2,9-linked polysialic acid capsular polysaccharide. This polysialic acid expressed on the surface of N. meningitidis and in the absence of specific antibody serves to evade host defense mechanisms. The polysialyltransferase (PST) that forms the group C polysialic acid (NmC PST) is located in the cytoplasmic membrane. Until recently, detailed characterization of bacterial polysialyltransferases has been hampered by a lack of availability of soluble enzyme preparations. We have constructed chimeras of the group C polysialyltransferase that catalyzes the formation alpha-2,9-polysialic acid as a soluble enzyme. We used site-directed mutagenesis to determine the region of the enzyme necessary for synthesis of the alpha-2,9 linkage. A chimera of NmB and NmC PSTs containing only amino acids 1 to 107 of the NmB polysialyltransferase catalyzed the synthesis of alpha-2,8-polysialic acid. The NmC polysialyltransferase requires an exogenous acceptor for catalytic activity. While it requires a minimum of a disialylated oligosaccharide to catalyze transfer, it can form high-molecular-weight alpha-2,9-polysialic acid in a nonprocessive fashion when initiated with an alpha-2,8-polysialic acid acceptor. De novo synthesis in vivo requires an endogenous acceptor. We attempted to reconstitute de novo activity of the soluble group C polysialyltransferase with membrane components. We found that an acapsular mutant with a defect in the polysialyltransferase produces outer membrane vesicles containing an acceptor for the alpha-2,9-polysialyltransferase. This acceptor is an amphipathic molecule and can be elongated to produce polysialic acid that is reactive with group C-specific antibody.

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The flow due to a finite disk rotating in an incompressible viscous fluid has been studied. A modified Newton-gradient finite difference scheme is used to obtain the solution of full Navier-Stokes equations numerically for different disk and cylinder sizes for a wide range of Reynolds numbers. The introduction of the aspect ratio and the disk-shroud gap, significantly alters the flow characteristics in the region under consideration, The frictional torque calculated from the flow data reveals that the contribution due to nonlinear terms is not negligible even at a low Reynolds number. For large Reynolds numbers, the flow structure reveals a strong boundary layer character.

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A binary aqueous suspension of large (L) and small (S) nearly-hard-sphere colloidal polystyrene spheres is shown to segregate spontaneously into L-rich and S-rich regions for suitable choices of volume fraction and size ratio. This is the first observation of such purely entropic phase separation of chemically identical species in which at least one component remains fluid. Simple theoretical arguments are presented to make this effect plausible.