We present a facile route which combines the functionalization of a highly oriented pyrolytic graphite surface with an atomic layer deposition (ALD) process to allow for conformal Al2O3 layers. While the trimethylaluminum (TMA)∕H2O process caused selective deposition only along step edges, the TMA∕O3 process began to provide nucleation sites on the basal planes of the surface. O3 pretreatment, immediately followed by the ALD process with TMA∕O3 chemistry, formed Al2O3 layers without any preferential deposition at the step edges. This is attributed to functionalization of graphene by ozone treatment, imparting a hydrophilic character which is desirable for ALD deposition.

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We investigate Λ(1520, 3/2 − , D 03 ) photoproduction via the γN → KΛ * process. Using effective Lagrangians, we compute the total and differential cross sections. The dependence on the momentum transfer for the photoproduction at the tree-level is also examined. We find that the total cross sections for the proton target are well reproduced as compared with the experimental data. It turns out that the total cross sections for the neutron target are significantly smaller than those for the proton one. We also compare the present results with the γN →KΘ + reaction in order to extract information of Θ + . The role of K * -exchange in the production reaction is also discussed.Recent interest in excited baryons has been largely motivated by new experimental developments [1]: The observation of the exotic Θ + resonance of strangeness S = +1 has triggered diverse activities in both experimental and theoretical studies. The finding of the Θ + has renewed interest in baryon spectroscopy. For instance, properties of the Λ(1405) has been reanalyzed, based on the idea of chiral perturbation theory and of dynamical generation from (anti) kaon-nucleon scattering. A meson-baryon bound-state picture suggests another type of the multi-quark structure. A spin-3/2 − partner of this resonance, i.e. Λ(1520) (≡ Λ * ) whose mass is similar to that of Θ + but strangeness is opposite is yet another interesting resonance. It can be produced simultaneously in the Θ + photoproduction from the deuteron target. The LEPS collaboration is searching for the Θ + associated with the production of the Λ * in photoproduction off the deuteron [2]. Since the measurement of the Λ * can be performed much more reliably, the detailed understanding of the production mechanism of this resonance would be useful to extract information of the Θ + .As far as the experimental data of the Λ * production are concerned, there are experiments reported so far: Boyarski (photoproduction)et al. [3], the Daresbury group (photoproduction) [4], and the CLAS collaboration (electroproduction) [5]. However, these two production mechanisms showed rather different tendencies: While in Ref.[3] and in the Daresbury experiment K * -exchange is known to be dominant in the t-channel, the CLAS experiment indicates that pseudoscalar K-exchange governs the process. Moreover, the kinematical regions of these experiments are different, so that a mere comparison is not meaningful.In the present work, we investigate the photoproduction of the Λ * near the threshold. Based on the effective Lagrangian for meson-baryon vertices, we use the Born approximation. We introduce form factors at the vertices, which reflect the internal structure of hadrons but bring in model dependence. However, there is a caveat: Introducing the form factors violates the gauge invariance of the electromagnetic interaction, which causes the Ward-Takahashi identity to be broken. Thus, we have to take care of the form factors to restore the gauge invariance. Since there is no unique theoretical way to introduce the g...

The electromagnetic form factors of the SU(3) octet baryons are investigated in the semibosonized SU(3) Nambu-Jona-Lasinio model (chiral quark-soliton model). The rotational 1/N c and strange quark mass corrections in linear order are taken into account. The electromagnetic charge radii of the nucleon and magnetic moments are also evaluated. It turns out that the model is in *

Twist-3 distribution amplitudes of the pion and kaon are studied in this paper. We calculate the fist several moments for the twist-3 distribution amplitudes (φ π p,σ and φ K p,σ) of the pion and kaon by applying the QCD sum rules. Our results show that, (i) the first three moments of φ K p and the first two moments of φ π p and φ π,K σ of the pion and kaon can be obtained with 30% uncertainty; (ii) the fourth moment of the φ π p and the second moment of the φ K σ can be obtained when the uncertainty are relaxed to 35%; (iii) the fourth moment of the φ π σ can be obtained only when the uncertainty are relaxed to 40%; (iv) we have m p 0π = 1.10 ± 0.08 GeV and m p 0K = 1.25 ± 0.15 GeV after including the α s-corrections to the perturbative part. These moments will be helpful for constructing the twist-3 wave functions of the pion and kaon.

The NAD-dependent histone/protein deacetylase activity of Sir2 (silent information regulator 2) accounts for its diverse biological roles including gene silencing, DNA damage repair, cell cycle regulation, and life span extension. We provide crystallographic evidence that 2-O-acetyl ADP-ribose is the reaction product that is formed at the active site of Sir2 from the 2.6-Å co-crystal structure of 2-O-acetyl-ADP-ribose and Sir2 from Archaeoglobus fulgidus. In addition, we show that His-116 and Phe-159 play critical roles in the catalysis and substrate recognition. The conserved Ser-24 and Asp-101 contribute to the stability for NAD binding rather than being directly involved in the catalysis. The crystal structures of wild type and mutant derivatives of Sir2, in conjunction with biochemical analyses of the mutants, provide novel insights into the reaction mechanism of Sir2-mediated deacetylation.

Magnetic moments of baryons are studied within the chiral quark soliton model with special emphasis on the decuplet of baryons. The model is used to identify all symmetry breaking terms proportional to m s . Sum rules for the magnetic moments are derived. A "model-independent" analysis of the symmetry breaking terms is performed and finally model calculations are presented, which show the importance of the rotational 1/N c corrections for cranking of the soliton.

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