On the momentum correlations in the fragmentation of <Superscript>197</Superscript>Au + <Superscript>197</Superscript>Au reactions

We aim to present the formation of fragments using static as well as momentum-dependent interactions and larger nucleonic cross-sections. We shall also examine, in detail, the role of momentum correlations in these situations which are close to the fire-ball as well as to the spectator matter decay. The role of momentum correlations will be studied by imposing an additional cut in the momentum space. A clear need of a momentum cut is demonstrated in both fire-ball as well as spectator matter physics. The momentum-dependent interactions and larger cross-sections play a drastic role in peripheral reactions, whereas the role of momentum cut remains the same in these situations.     

Search for lepton flavor violation in K+ decays into a charged pion and two leptons

A search for lepton flavor violating decays, K+ --> mu+ mu+ pi-, K+ --> e+ e+ pi-, K+ --> pi+ e+ mu-, K+ --> mu+ e+ pi-, and pi0 --> e+ mu-, was performed using the data collected in Experiment E865 at the Brookhaven Alternating Gradient Synchrotron. No signal was found in any of the decay modes. At the 90% confidence level, the branching ratios are less than 3.0x10(-9), 6.4x10(-10), 5. 2x10(-10), 5.0x10(-10), and 3.4x10(-9), respectively.     

Assignment of the Phosphorus,Proton and Carbon-NMR Spectra of [(Tetrahydro-2-hydroxy-5,5-dimethyl-4H-1,4,2-oxazaphosphorin-4-yl)methyl] phosphonic acid P-Oxide

The ¹H and ¹³C nmr signals of the methylene groups directly linked to the phosphorus atoms, namely P(2)-C(3)H₂ and P(8)-C(7)H₂ in 1a were assigned with the help of hetronuclear decoupling experiments and HETCOR spectrum.     

Palladium-catalyzed multicomponent coupling of alkynes, imines, and acid chlorides: a direct and modular approach to pyrrole synthesis

A new palladium-catalyzed method to prepare pyrroles directly from three basic building blocks-imines, alkynes, and acid chlorides-is described. This approach provides a straightforward method both to prepare pyrroles in one step and to diversify their structure by simple variation of any of the three starting materials. Mechanistic studies suggest that this process occurs via a complex series of eight individual steps, and this is discussed.     

Development of a laser-induced cell lysis system

A novel cell lysis system was developed that is based on laser-induced disruption of bacterial and yeast cells. It will find application as a rapid, efficient and clean sample preparation step in bioanalytical detection systems. Using E. coli as our model analyte, we optimized cell lysis with respect to optimal laser wavelength, lowest energy input requirements, RNA release from the cells, and potential protein damage. The optimized system was finally applied to the lysis of four additional microorganisms. All experiments were carried out with about 2000 cells per sample or less. Initially, lysis was determined by the detection of cell survival after laser treatment using standard microbiological techniques, (i.e., cells were grown on nutrient agar plates). Then, actual release of mRNA from the cells was proven. Wavelengths investigated ranged from 500 nm to 1550 nm. An average power of 100 mW for the lasers was shown to be sufficient to obtain cell lysis at wavelengths above 1000 nm, with optimal wavelengths between 1250 nm and 1550 nm. Since water absorbs energy at those wavelengths, it is assumed that laser exposure results in an instantaneous increase of the cell temperature, which causes rupture of the cell membrane. Second, damage to protein solutions treated under optimized laser-lysis conditions was also studied. Using a pure solution of horseradish peroxidase as a model protein, no loss in enzyme activity was observed. Thus, it was concluded that damage to intracellular proteins is unlikely. Third, RNA release was tested using an E. coli specific RNA biosensor. Release of RNA was not detected from untreated cells, but laser-treated E. coli cells displayed significant RNA release due to laser-induced cell lysis. Finally, lysis of M. luteus, B. subtilis, B. cereus, and S. cerevisiae were investigated under optimized conditions. In all cases, laser-induced lysis of the cells was confirmed by determination of cell survival. Hence, laser-induced cell lysis is an efficient procedure that can be used for sample preparation, without damage to macromolecules, in bioanalytical detection systems for microorganisms. Miniaturized lasers and miniaturized cell-lysis chambers will create a simple, field-usable cell lysis system and allow the application of laser-induced cell lysis in micro Total Analysis Systems.     

Contemporary review of techniques for the solution of nonlinear Burgers equation

In the present paper, a comprehensive review of the different techniques used for solving the Burgers equation has been presented along with the recent progress going in finding its solution. The main objective of this paper is not only to present a proper assessment of the previous work but also to provide readers with all fruitful existing information that can help in numerical solution of the Burgers equation, which is otherwise difficult to solve under certain assumptions. Comments are supplied with each reference cited, in order to briefly summarize the objectives of the specific analysis and the important results therein. In addition, a brief discussion of a contribution by the authors in this field has also been presented at the end.