Synthetic Studies With Pinus Elliottiis' Rosin Derivatives. Oxidation Of Maleopimaric Anhydride Methyl Ester And Trimethyl Fumaropimarate

Ozonolysis of maleopimaric anhydride methyl ester in the presence of tetracyanoethylene led to an epoxide and an ozonide. Ozonolysis of the trimethyl fumaropimarate, followed by treatment with Me2S, led to an epoxide, a diene, a keto-acid and an allylic oxidation product. Some of the compounds obtained were active against Staphylococcus aureus, Bacillus subtilis and Micrococcus luteus.1115963Seebacher, W., Hüfner, A., Haslingeer, E., Weis, R., (1995) Monatsh. Chem., 129, p. 697. , and references cited thereinKsabati, M.B., Schimtz, F.J., (1987) J. Org. Chem., 52, p. 3766Miyamoto, T., Sakamoto, K., Arao, K., Komori, T., Higuchi, R., Sasaki, T., (1996) Tetrahedron, 52, p. 8187Zalkow, L.H., Ford, R.A., Kutney, J.P., (1962) J. Org. Chem., 27, p. 3535Zalkow, L.H., Brannon, D.R., (1964) J. Org. Chem., 29, p. 1296Zalkow, L.H., Girotra, N.N., (1963) J. Org. Chem., 28, p. 2033Zalkow, L.H., Kulkarni, M.V., Girotra, N.N., (1965) J. Org. Chem., 30, p. 1679Halbrook, N.J., Lawrence, R.V., Dressler, R.L., Blackstone, R.C., Herz, W., (1964) J. Org. Chem., 29, p. 1017Santos, C., Rosso, C.R.S., Imamura, P., (1999) M. Synth. Commun., 29, p. 1903Bailey, P.S., (1978) Ozonization in Organic Chemistry, 1. , Academic Press, New YorkHerz, W., Blackstone, R.C., (1969) Atmos Environ, 34, p. 1257Atmos Environ, p. 135Masaki, Y., Miura, T., Ochiai, M., (1996) Bull. Chem. Soc. Jpn., 69, p. 195. , and references cited thereinThe ozonide could be stored in a freezer without decomposition at -5°C for few weeksShiojima, K., Masuda, K., Ageta, K., (1990) Chem. Pharm. Bull., 38, p. 79Li, T., Yang, Y., Li, Y., (1993) J. Chem. Res. (S), p. 30Carlsen, P.H.J., Katsuki, T., Martin, V.S., Sharpless, K.B., (1981) J. Org. Chem., 46, p. 3936Funk, R.L., Abelman, M.M., (1986) J. Org. Chem., 51, p. 3247For convenience, the numbering of carbons for 14 was used the same given for 3Sam, D.J., Simmons, H.F., (1972) J. Am. Chem. Soc., 94, p. 4024Ferreira, J.T.B., Cruz, W.O., Vieira, P.C., Yonashiro, M., (1987) J. Org. Chem., 52, p. 3698Mitra, R.B., Muljiani, Z., Deshmukh, A.R.A., (1982) S. Synth. Commun., 12, p. 1063Aristoff, P.A., Johnson, P.D., Harrison, A.W., (1985) J. Am. Chem. Soc., 107, p. 7961Homans, A.L., Fuchs, A., (1970) J. Chromatogr., 75, p. 327Hamburger, M.O., Cordell, G.A., (1987) J. Nat. Prod., 50, p. 19Bruch, M.K., (1991) Methods of Testing Antiseptics: Antimicrobials Used Topically in Humans and Procedures for Hand Scrubs, in Disinfection, Sterilization and Preservation, 4th. Ed., , Lea & Febinger, PhiladelphiaHalbrook, N.J., Lawrence, R.V., (1958) J. Am. Chem. Soc., 80, p. 36

Linear response conductance and magneto-resistance of ferromagnetic single-electron transistors

The current through ferromagnetic single-electron transistors (SET's) is considered. Using path integrals the linear response conductance is formulated as a function of the tunnel conductance vs. quantum conductance and the temperature vs. Coulomb charging energy. The magneto-resistance of ferromagnet-normal metal-ferromagnet (F-N-F) SET's is almost independent of the Coulomb charging energy and is only reduced when the transport dwell time is longer than the spin-flip relaxation time. In all-ferromagnetic (F-F-F) SET's with negligible spin-flip relaxation time the magneto-resistance is calculated analytically at high temperatures and numerically at low temperatures. The F-F-F magneto-resistance is enhanced by higher order tunneling processes at low temperatures in the 'off' state when the induced charges vanishes. In contrast, in the 'on' state near resonance the magneto-resistance ratio is a non-monotonic function of the inverse temperature.Comment: 10 pages, 6 figures. accepted for publication in Phys. Rev.

Effect of a Domain Wall on the Conductance Quantization in a Ferromagnetic Nanowire

The effect of the domain wall (DW) on the conductance in a ballistic ferromagnetic nanowire (FMNW) is revisited by exploiting a specific perturbation theory which is effective for a thin DW; the thinness is often the case in currently interested conductance measurements on FMNWs. Including the Hund coupling between carrier spins and local spins in a DW, the conductance of a FMNW in the presence of a very thin DW is calculated within the Landauer-B\"{u}ttiker formalism. It is revealed that the conductance plateaus are modified significantly, and the switching of the quantization unit from $e^2/h$ to ``about $2e^2/h$'' is produced in a FMNW by the introduction of a thin DW. This accounts well for recent observations in a FMNW.Comment: 5 pages, 2 figures, Corrected typos and added reference

Ballistic versus diffusive magnetoresistance of a magnetic point contact

The quasiclassical theory of a nanosize point contacts (PC) between two ferromagnets is developed. The maximum available magnetoresistance values in PC are calculated for ballistic versus diffusive transport through the area of a contact. In the ballistic regime the magnetoresistance in excess of few hundreds percents is obtained for the iron-group ferromagnets. The necessary conditions for realization of so large magnetoresistance in PC, and the experimental results by Garcia et al are discussedComment: 4 pages, TEX, 1 Figur

Electronic transport through domain walls in ferromagnetic nanowires: Co-existence of adiabatic and non-adiabatic spin dynamics

We study the effect of a domain wall on the electronic transport in ferromagnetic quantum wires. Due to the transverse confinement, conduction channels arise. In the presence of a domain wall, spin up and spin down electrons in these channels become coupled. For very short domain walls or at high longitudinal kinetic energy, this coupling is weak, leads to very few spin flips, and a perturbative treatment is possible. For very long domain wall structures, the spin follows adiabatically the local magnetization orientation, suppressing the effect of the domain wall on the total transmission, but reversing the spin of the electrons. In the intermediate regime, we numerically investigate the spin-dependent transport behavior for different shapes of the domain wall. We find that the knowledge of the precise shape of the domain wall is not crucial for determining the qualitative behavior. For parameters appropriate for experiments, electrons with low longitudinal energy are transmitted adiabatically while the electrons at high longitudinal energy are essentially unaffected by the domain wall. Taking this co-existence of different regimes into account is important for the understanding of recent experiments.Comment: 10 pages, 6 figure

Reflection of electrons from a domain wall in magnetic nanojunctions

Electronic transport through thin and laterally constrained domain walls in ferromagnetic nanojunctions is analyzed theoretically. The description is formulated in the basis of scattering states. The resistance of the domain wall is calculated in the regime of strong electron reflection from the wall. It is shown that the corresponding magnetoresistance can be large, which is in a qualitative agreement with recent experimental observations. We also calculate the spin current flowing through the wall and the spin polarization of electron gas due to reflections from the domain wall.Comment: 7 pages, 4 figure

Current Fluctuations of the One Dimensional Symmetric Simple Exclusion Process with Step Initial Condition

For the symmetric simple exclusion process on an infinite line, we calculate exactly the fluctuations of the integrated current $Q_t$ during time $t$ through the origin when, in the initial condition, the sites are occupied with density $\rho_a$ on the negative axis and with density $\rho_b$ on the positive axis. All the cumulants of $Q_t$ grow like $\sqrt{t}$. In the range where $Q_t \sim \sqrt{t}$, the decay $\exp [-Q_t^3/t]$ of the distribution of $Q_t$ is non-Gaussian. Our results are obtained using the Bethe ansatz and several identities recently derived by Tracy and Widom for exclusion processes on the infinite line.Comment: 2 figure

Fertility, Living Arrangements, Care and Mobility

There are four main interconnecting themes around which the contributions in this book are based. This introductory chapter aims to establish the broad context for the chapters that follow by discussing each of the themes. It does so by setting these themes within the overarching demographic challenge of the twenty-first century – demographic ageing. Each chapter is introduced in the context of the specific theme to which it primarily relates and there is a summary of the data sets used by the contributors to illustrate the wide range of cross-sectional and longitudinal data analysed

Genomic analysis of diet composition finds novel loci and associations with health and lifestyle

We conducted genome-wide association studies (GWAS) of relative intake from the macronutrients fat, protein, carbohydrates, and sugar in over 235,000 individuals of European ancestries. We identified 21 unique, approximately independent lead SNPs. Fourteen lead SNPs are uniquely associated with one macronutrient at genome-wide significance (P < 5 × 10−8), while five of the 21 lead SNPs reach suggestive significance (P < 1 × 10−5) for at least one other macronutrient. While the phenotypes are genetically correlated, each phenotype carries a partially unique genetic architecture. Relative protein intake exhibits the strongest relationships with poor health, including positive genetic associations with obesity, type 2 diabetes, and heart disease (rg ≈ 0.15–0.5). In contrast, relative carbohydrate and sugar intake have negative genetic correlations with waist circumference, waist-hip ratio, and neighborhood deprivation (|rg| ≈ 0.1–0.3) and positive genetic correlations with physical activity (rg ≈ 0.1 and 0.2). Relative fat intake has no consistent pattern of genetic correlations with poor health but has a negative genetic correlation with educational attainment (rg ≈−0.1). Although our analyses do not allow us to draw causal conclusions, we find no evidence of negative health consequences associated with relative carbohydrate, sugar, or fat intake. However, our results are consistent with the hypothesis that relative protein intake plays a role in the etiology of metabolic dysfunction

Genomic analysis of diet composition finds novel loci and associations with health and lifestyle

We conducted genome-wide association studies (GWAS) of relative intake from the macronutrients fat, protein, carbohydrates, and sugar in over 235,000 individuals of European ancestries. We identified 21 unique, approximately independent lead SNPs. Fourteen lead SNPs are uniquely associated with one macronutrient at genome-wide significance (P < 5 x 10(-8)), while five of the 21 lead SNPs reach suggestive significance (P < 1 x 10(-5)) for at least one other macronutrient. While the phenotypes are genetically correlated, each phenotype carries a partially unique genetic architecture. Relative protein intake exhibits the strongest relationships with poor health, including positive genetic associations with obesity, type 2 diabetes, and heart disease (r(g) approximate to 0.15-0.5). In contrast, relative carbohydrate and sugar intake have negative genetic correlations with waist circumference, waist-hip ratio, and neighborhood deprivation (|r(g)| approximate to 0.1-0.3) and positive genetic correlations with physical activity (r(g) approximate to 0.1 and 0.2). Relative fat intake has no consistent pattern of genetic correlations with poor health but has a negative genetic correlation with educational attainment (r(g) approximate to-0.1). Although our analyses do not allow us to draw causal conclusions, we find no evidence of negative health consequences associated with relative carbohydrate, sugar, or fat intake. However, our results are consistent with the hypothesis that relative protein intake plays a role in the etiology of metabolic dysfunction.Public Health and primary carePrevention, Population and Disease management (PrePoD