996 resultados para C template metaprogramming
Resumo:
Attempts have been made to understand the nature and significance of hydrogen bonds of the type X-H-C (X = 0, N) . These unusual interactions have been discussed recently. Crystallographic studies on 17a-ethynylandrosta- 2,4-dieno[2,3-d]dihydroxazol1-7 8-01 (donazole) provide direct evidence of such an 0-H.0-C interaction. Ab initio computations, IR spectroscopy, and database studies show that these hydrogen bonds, while uncommon, are energetically and structurally significant.
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Sika- ja siipikarjatilojen määrä Suomessa on vähentynyt koko EU-jäsenyyden ajan tuotannon keskittyessä yhä suurempiin yksiköihin. Tuotantomäärät ovat kasvaneet, mutta viljelijöiden tulotaso on alentunut, joten maatalouden ulkopuoliset ammatit houkuttelevat luopumaan eläinten pidosta tai maataloudesta kokonaan. Sika- ja siipikarjatalouden rakennemuutoksen taloudellisena kannustimena otettiin vuonna 2009 käyttöön sika- ja siipikarjatalouden rakennemuutoskorvaus, jota maksetaan kompensaationa sika- ja siipikarjataloudesta luopuville viljelijöille. Tämän työn tarkastelukohteena on rakennemuutoskorvaus C-tukialueella, jossa yksinään on lähes yhtä paljon sika- ja siipikarjatiloja kuin A- ja B-alueilla yhteensä. Tutkimuksen tavoitteena on selvittää, millaiset sika- ja siipikarjatilat sekä koko C-alueella että C-alueen eri osissa ovat hakeneet rakennemuutoskorvausta ja miten tilat ovat alueellisesti sijoittuneet. Maatalouden rakennepolitiikalla pyritään vaikuttamaan maatalouden yhteiskunnalliseen rakenteeseen. Rakennepoliittisilla toimilla pyritään vähentämään viljelijöiden ja tilojen määrää, jolloin maataloustulo jakaantuu pienemmälle viljelijämäärälle taaten heille suuremmat tulot. Maatalouden rakennemuutosta tapahtuu, kun maatalouden rakenteessa tapahtuu tietyllä aikavälillä muutos. Rakennemuutoksessa ja -kehityksessä on alueellisia eroja. Aluetaloustiede pyrkii selittämään, mistä alueelliset erot johtuvat ja miksi alueet erilaistuvat. Suomessa eri maakunnilla on eroja ja omia alueellisia ominaispiirteitään, joilla on suuri merkitys alueen työllisyyteen ja väestön sijoittumiseen alueella. Eri maakunnissa työllisyystilanne on vaihteleva, mutta joka maakunnassa on kuitenkin työvoimapulaa useissa sellaisissa ammateissa, joihin eläinten tai tilan pidon lopettavien viljelijöiden olisi mahdollista työllistyä. Sika- ja siipikarjatalouden rakennemuutoskorvaus on kansallinen kotieläintuki, jota maksetaan tilakohtaisen viitemäärän perusteella tiloille, jotka ovat juuri lopettaneet sika- ja siipikarjatuotantonsa tai aikovat sen lopettaa. Korvausta on voitu maksaa tukiehdot täyttävälle tuenhakijalle joko vuosina 2009–2010 tai vuosina 2010–2011 ja sen maksimimäärä on tilaa kohden enintään 20000 euroa vuodessa. Kahden korvausvuoden jälkeen tilan viitemäärä lakkautetaan ja sen jälkeen tilalle ei enää makseta sika- ja siipikarjatalouden tukia. Tilan on kuitenkin edelleen mahdollista jatkaa sika- ja siipikarjatuotantoaan markkinaehtoisena. Tutkimuksen aineisto on 389 tilan tiedot sisältävä Tiken raportti tukityypin 1612 (sika- ja siipikarjatalouden rakennemuutoskorvaus, pohjoinen) tukihakutiedoista vuodelta 2010. Tutkimusote oli kvantitatiivinen ja koska havaintoaineisto kattaa kaikki C-alueen korvauksenhakijat, tehtiin tutkimus kokonaistutkimuksena. Tutkimustulosten mukaan 63 % korvausta hakeneista tiloista sijoittuu C1-alueelle ja 54 % Etelä-Pohjanmaalle ja Pohjanmaalle. Kuntatasolla eniten rakennemuutoskorvaustiloja oli Närpiössä. C-alueella tuenhakijat olivat iältään 20–71-vuotiaita. Hakijoista 62 % harjoitti päätuotantosuuntanaan viljanviljelyä ja peltoalaa kaikilla hakijoilla oli hallinnassaan lähes 16000 ha. Rakennemuutoskorvausta maksettiin C-alueella yhteensä yli 2,3 miljoonaa euroa. Kun rakennemuutoskorvauksen viitemäärät kahden korvausvuoden jälkeen lakkautetaan, poistuu tuo-tannosta yli 9600 ey. Sekä C-alueella että kaikki ELY-keskukset huomioiden oli korvauksenhakijoita kaikkia ikäluokkia tarkasteltaessa eniten 50–59-vuotiaissa. Eniten hakijoita oli viitemääräluokassa 10,01–20 ey ja viljelyalaluokassa 25,01–40 ha, vähiten luokissa 40,01–50 ey ja 50,01 ey tai enemmän sekä 150,01 ha tai enemmän. Yleisin maksuluokka oli 3000,01–4500 euroa, harvinaisin 15000,01–20000 euroa. Rakennemuutoskorvauksella saavutettuja hyötyjä ja kustannuksia on toistaiseksi vaikea määritellä, koska vuoden 2011 maksatus on vielä kesken.
Resumo:
Ab initio computations Predict a minimum for a carbon-carbon quadruple bond in C2. While the computed C-C separation, 1.128 angstrom, fits Pauling's bond order-bond length relationship well, this result is an artifact of the restricted Hartree Fock theory.
Resumo:
(I)Lantadene-B: C35H52O5,M r =552.80, MonoclinicC2,a=25.65(1),b=6.819(9),c=18.75(1) Å,beta=100.61(9),V=3223(5) Å3,Z=4,D x =1.14 g cm–3 CuKagr (lambda=1.5418A),mgr=5.5 cm–1,F(000)=1208,R=0.118,wR=0.132 for 1527 observed reflections withF o ge2sgr(F o ). (II)Lantadene-C: C35H54O5·CH3OH,Mr=586.85, Monoclinic,P21,a=9.822(3),b=10.909(3),c=16.120(8)Å,beta=99.82(4),V=1702(1)Å3,Z=2,D x =1.145 g cm–3, MoKagr (lambda=0.7107Å), mgr=0.708 cm–1 F(000)=644,R=0.098, wR=0.094 for 1073 observed reflections. The rings A, B, C, D, and E aretrans, trans, trans, cis fused and are in chair, chair, sofa, half-chair, chair conformations, respectively, in both the structures. In the unit cell the molecules are stabilized by O-HctdotO hydrogen bonds in both the structures, however an additional C-HctdotO interaction is observed in the case of Lantadene-C.
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The current standard of care for hepatitis C virus (HCV) infection - combination therapy with pegylated interferon and ribavirin - elicits sustained responses in only similar to 50% of the patients treated. No alternatives exist for patients who do not respond to combination therapy. Addition of ribavirin substantially improves response rates to interferon and lowers relapse rates following the cessation of therapy, suggesting that increasing ribavirin exposure may further improve treatment response. A key limitation, however, is the toxic side-effect of ribavirin, hemolytic anemia, which often necessitates a reduction of ribavirin dosage and compromises treatment response. Maximizing treatment response thus requires striking a balance between the antiviral and hemolytic activities of ribavirin. Current models of viral kinetics describe the enhancement of treatment response due to ribavirin. Ribavirin-induced anemia, however, remains poorly understood and precludes rational optimization of combination therapy. Here, we develop a new mathematical model of the population dynamics of erythrocytes that quantitatively describes ribavirin-induced anemia in HCV patients. Based on the assumption that ribavirin accumulation decreases erythrocyte lifespan in a dose-dependent manner, model predictions capture several independent experimental observations of the accumulation of ribavirin in erythrocytes and the resulting decline of hemoglobin in HCV patients undergoing combination therapy, estimate the reduced erythrocyte lifespan during therapy, and describe inter-patient variations in the severity of ribavirin-induced anemia. Further, model predictions estimate the threshold ribavirin exposure beyond which anemia becomes intolerable and suggest guidelines for the usage of growth hormones, such as erythropoietin, that stimulate erythrocyte production and avert the reduction of ribavirin dosage, thereby improving treatment response. Our model thus facilitates, in conjunction with models of viral kinetics, the rational identification of treatment protocols that maximize treatment response while curtailing side effects.
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The t(14;18) translocation in follicular lymphoma is one of the most common chromosomal translocations. Most breaks on chromosome 18 are located at the 3'-UTR of the BCL2 gene and are mainly clustered in the major breakpoint region (MBR). Recently, we found that the BCL2 MBR has a non-B DNA character in genomic DNA. Here, we show that single-stranded DNA modeled from the template strand of the BCL2 MBR, forms secondary structures that migrate faster on native PAGE in the presence of potassium, due to the formation of intramolecular G-quadruplexes. Circular dichroism shows evidence for a parallel orientation for G-quadruplex structures in the template strand of the BCL2 MBR. Mutagenesis and the DMS modification assay confirm the presence of three guanine tetrads in the structure. 1H nuclear magnetic resonance studies further confirm the formation of an intramolecular G-quadruplex and a representative model has been built based on all of the experimental evidence. We also provide data consistent with the possible formation of a G-quadruplex structure at the BCL2 MBR within mammalian cells. In summary, these important features could contribute to the single-stranded character at the BCL2 MBR, thereby contributing to chromosomal fragility.
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By using the lower bound limit analysis in conjunction with finite elements and linear programming, the bearing capacity factors due to cohesion, surcharge and unit weight, respectively, have been computed for a circular footing with different values of phi. The recent axisymmetric formulation proposed by the authors under phi = 0 condition, which is based on the concept that the magnitude of the hoop stress (sigma(theta)) remains closer to the least compressive normal stress (sigma(3)), is extended for a general c-phi soil. The computational results are found to compare quite well with the available numerical results from literature. It is expected that the study will be useful for solving various axisymmetric geotechnical stability problems. Copyright (C) 2010 John Wiley & Sons, Ltd.
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MnO/C composite coatings were grown by the metalorganic chemical vapor deposition process on ceramic alumina in argon ambient. Characterization by various techniques confirms that these coatings are homogeneous composites comprising nanometer-sized MnO particles embedded in a matrix of nanometer-sized graphite. Components of the MnO/C composite coating crystalline disordered, but are electrically quite conductive. Resistance vs. temperature measurements show that coating resistance increases exponentially from a few hundred ohms at room temperature to a few megaohms at 30 K. Logarithmic plots of reduced activation energy vs. temperature show that the coating material undergoes a metal-insulator transition. The reduced activation energy exponent for the film under zero magnetic field was 2.1, which is unusually high, implying that conduction is suppressed at much faster rate than the Mott or the Efros-Shklovskii hopping mechanism. Magnetoconductance us. magnetic field plots obtained at various temperatures show a high magnetoconductance (similar to 28.8%) at 100 K, which is unusually large for a disordered system, wherein magnetoresistance is attributed typically to weak localization. A plausible explanation for the unusual behavior observed in the carbonaceous disordered composite material is proposed. (C) 2010 Elsevier Ltd. All rights reserved.
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An in vitro transcription system from Candida utilis is described. The template used is a hybrid plasmid containing Saccharomyces cerevisiae CYC1 promoter linked to a synthetic 377-bp G-minus casette (1). In vitro transcriptions are carried out in the presence of RNase. T1. Under these conditions only the transcripts that are resistant to RNase T1 accumulate. Using this protocol, it has been shown that in the absence of cytosolic factors RNA polymerase II (pol II) from C. utilis initiated RNA synthesis randomly. But both C. utilis and S. cerevisiae cell-free extracts could direct pol II from C. utilis to initiate transcription accurately. Results also indicated that the general transcription factors are functionally interchangeable between S. cerevisiae and C. utilis
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We present a first-principles theory of the equilibrium b.c.c.-f.c.c. interface at coexistence using the density functional method. We assume that the interfacial region has local body-centred tetragonal (b.c.t.) symmetry and predict typical interfacial widths to be of order 2 to 3 lattice spacings with typical energies close to 0.05 J/m2. These quantities are in good agreement with laboratory measurements on coherent interfaces.
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Cytochrome c, a "mobile electron carrier" of the mitochondrial respiratory chain, also occurs in detectable amounts in the cytosol, and can receive electrons from cytochromes present in endoplasmic reticulum and plasma membranes as well as from superoxide and ascorbate. The pigment was found to dissociate from mitochondrial membranes in liver and kidney when rats were subjected to heat exposure and starvation, respectively. Treating cytochrome c with hydroxylamine gives a partially deaminated product with altered redox properties; decreased stimulation of respiration by deficient mitochondria, increased reduction by superoxide, and complete loss of reducibility by plasma membranes. Mitochondria isolated from brown adipose tissue of cold-exposed rats are found to be sub-saturated with cytochrome c. The ability of cytochrome c to reactivate reduced ribonuclease is now reinterpreted as a molecular chaperone role for the hemoprotein.
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We review work initiated and inspired by Sudarshan in relativistic dynamics, beam optics, partial coherence theory, Wigner distribution methods, multimode quantum optical squeezing, and geometric phases. The 1963 No Interaction Theorem using Dirac's instant form and particle World Line Conditions is recalled. Later attempts to overcome this result exploiting constrained Hamiltonian theory, reformulation of the World Line Conditions and extending Dirac's formalism, are reviewed. Dirac's front form leads to a formulation of Fourier Optics for the Maxwell field, determining the actions of First Order Systems (corresponding to matrices of Sp(2,R) and Sp(4,R)) on polarization in a consistent manner. These groups also help characterize properties and propagation of partially coherent Gaussian Schell Model beams, leading to invariant quality parameters and the new Twist phase. The higher dimensional groups Sp(2n,R) appear in the theory of Wigner distributions and in quantum optics. Elegant criteria for a Gaussian phase space function to be a Wigner distribution, expressions for multimode uncertainty principles and squeezing are described. In geometric phase theory we highlight the use of invariance properties that lead to a kinematical formulation and the important role of Bargmann invariants. Special features of these phases arising from unitary Lie group representations, and a new formulation based on the idea of Null Phase Curves, are presented.
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Cylindrical specimens of textured commercial pure alpha-titanium plate, cut with the cylinder axis along the rolling direction for one set of experiments and in the long transverse direction for the other set, were compressed at strain rates in the range of 0.001 to 100 s-1 and temperatures in the range of 25-degrees-C to 400-degrees-C. At strain rates greater-than-or-equal-to 1 s-1, both sets of specimens exhibited adiabatic shear bands, but the intensity of shear bands was found to be higher in the rolling direction specimens than in the long transverse direction specimens. At strain rates -0.1 s-1, the material deformed in a microstructurally inhomogeneous fashion. For the rolling direction specimens, cracking was observed at 100-degrees-C and at strain rates -0.1 s-1. This is attributed to dynamic strain aging. Such cracking was not observed in the long transverse specimens. The differences in the intensity of adiabatic shear bands and that of dynamic strain aging between the two sets of test specimens are attributed to the strong crystallographic texture present in these plates.
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We re-examine holographic versions of the c-theorem and entanglement entropy in the context of higher curvature gravity and the AdS/CFT correspondence. We select the gravity theories by tuning the gravitational couplings to eliminate non-unitary operators in the boundary theory and demonstrate that all of these theories obey a holographic c-theorem. In cases where the dual CFT is even-dimensional, we show that the quantity that flow is the central charge associated with the A-type trace anomaly. Here, unlike in conventional holographic constructions with Einstein gravity, we are able to distinguish this quantity from other central charges or the leading coefficient in the entropy density of a thermal bath. In general, we are also able to identify this quantity with the coefficient of a universal contribution to the entanglement entropy in a particular construction. Our results suggest that these coefficients appearing in entanglement entropy play the role of central charges in odd-dimensional CFT's. We conjecture a new c-theorem on the space of odd-dimensional field theories, which extends Cardy's proposal for even dimensions. Beyond holography, we were able to show that for any even-dimensional CFT, the universal coefficient appearing the entanglement entropy which we calculate is precisely the A-type central charge.