Ion-molecule reactions of 2-methoxyethanol with some amines, carboxylic acids and amino acids under chemical ionization conditions

2-Methoxyethanol chemical ionization of amines, carboxylic acids and amino acids has been found to produce numerous adduct ions. The most intense adduct ions for amines are [M + H](+) and [M + 77](+), for carboxylic acids [M + 27](+), [M + 59](+) and [M + 77](+), and for amino acids [M + H](+), [M + 13](+), [M + 27](+) and [M + 77](+). Either the adduct ion [M + H](+) or [M + 77](+) was the most abundant ion found for amino acids. The proton affinities of amino acids are noticed to control the formation of the [M + H](+) and [M + 77](+) ions. The relative abundance of [M + 13](+) and [M + 27](+) ions varied for different amino acids being most intense for phenylalanine and aspartic acid. Copyright 1999 John Wiley & Sons, Ltd.     

Status of electroweak phase transition and baryogenesis

I review recent progress on the electroweak phase transition and baryogenesis, focusing on the minimal supersymmetric Standard Model as the source of new physics.     

An overlapping additive Schwarz preconditioner for the Laplace-Beltrami equation using spherical splines

We present an overlapping domain decomposition technique for solving the Laplace?CBeltrami equation on the sphere with spherical splines. We prove that the condition number of the additive Schwarz operator is bounded by $O\left(H^2/h^2\right)$ , where H and h are the sizes of the coarse and fine meshes, respectively. In the case that the degree of the splines is even, a better bound $O\left(\max_{1\leq k \leq J}\left(1+H_k/\delta_k\right)\right)$ is proved. Here J is the number of subdomains, H _k is the size of the kth subdomain, and ?? _k is the size of the overlap of the kth subdomain. The method is illustrated by numerical experiments on large point sets taken from magsat satellite data.     

连续波锁模P_r~（3＋）：YLF激光器

本文报导了采用氩离子激光器来泵浦Ｒｒ￣（３＋）：ＹＬＦ晶体，应用声光调制器实现了主动锁模；同时应用振动─高反射平面镜也实现了被动锁模，两种锁模均得到了ｐｓ光脉冲。据作者了解这是这种晶体材料的第一次锁模运转。     

Halfway house variational continuum distorted wave theory: high energy cross sections in the distorted wave perturbation approximation

The total cross section for charge transfer at high but non-relativistic energy is investigated within a new time-independent wave version of the halfway-house phase integral variational continuum distorted wave formalism, using simple first order perturbation theory. Following Crothers, Dubé and Brown this theory satisfies all known short and long range Coulomb boundary conditions which is essential if intermediate elastic divergences are to be avoided. The discussion is specialised to the particular case ofls →ls capture. Numerical results for this amplitude are obtained by a double numerical integration. Wave results derived for the capture process $$P^{Z_P^ + } + (T^{Z_T^ + } + e^ - ) \to (P^{Z_P^ + } + e^ - ) + T^{Z_T^ + } $$ in the caseZ _T = 1 =Z _P are compared with various theoretical impact parameter models and experimental data. Representative distributions of the total cross sections are presented as a function of the impact energy.     

Contribution of oligosaccharides to protection of the H,K-ATPase beta-subunit against trypsinolysis

The proton-pumping H+,K+-adenosinetriphosphatase (H,K-ATPase), responsible for acid secretion by the gastric parietal cell, faces a harshly acidic environment, with some pepsin from neighboring chief cells, at its luminal surface. Its large catalytic alpha-subunit is mostly oriented cytoplasmically. The smaller beta-subunit (HKbeta), is mainly extracellular, with one transmembrane domain and a small cytoplasmic domain. Seven N-linked oligosaccharides in the extracellular domain of HKbeta are thought to contribute to protection of the H,K-ATPase, since previous work has shown that their complete removal, by peptide N-glycosidase F (PNGase F), greatly increased susceptibility of HKbeta to proteolysis. The possibility of graded protection by different numbers of oligosaccharides was investigated here with the use of mutant HKbeta cDNA, having various N-glycosylation sites mutated (Asn to Gln), transfected into HEK-293 cells. Membrane preparations, two days after transfection, were solubilized in 1% Triton X-100 and subjected to trypsinolysis (pH 8, 37 degrees C, trypsin:protein 1:10-1:25). Relative amounts of HKbeta remaining after 20 min trypsin were determined, after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and probing of Western blots with an antibody to the HKbeta extracellular domain, by chemiluminescent development of blots and densitometry of resulting films. Maturely glycosylated HKbeta was made significantly more susceptible to trypsin than wild type when at least five oligosaccharides were deleted, while the high-mannose form (pre-beta), from the endoplasmic reticulum, became significantly more susceptible than wild-type pre-beta with removal of only two or more oligosaccharides. For each mutant, and wild type, pre-beta was consistently more susceptible than the mature form. While the number, and kind, of oligosaccharides seem to affect protection for HKbeta against trypsinolysis, other aspects of protein maturation, including proper folding of peptide domains and possible subtle alterations of conformation during Golgi processing, are also likely to contribute to this protection.