On non-linear periodic differential equations and associated point mappings. Application to stability problems

In this paper a method is given allowing the determination of the lower degree terms of a point mapping (i.e. recurrent relationship) associated to a non-linear differential equation with time periodic coefficients. This permits the study of some resonance phenomena. An example of application is given.     

Binding energy of finite nuclei in Jastrow-Factor-Cluster method with applications in helium

A general expression for the binding energy of finite nuclei in the Jastrow-Factor-Cluster method is developed upto the three-body cluster term with centre of mass correction. It is applied in massA=3 and 4 with the standard Chakkalakal function and the average Pauli condition. Compared to the previous work of Afnan (1969) better saturation properties are obtained for two- and three-body truncation. Convergence is also better.     

Multi-residue analytical methods using LC-tandem MS for the determination of pharmaceuticals in environmental and wastewater samples: a review

Multi-residue analytical methodologies are becoming the preferred and required tools against single group analysis, as they provide wider knowledge about the occurrence of pharmaceuticals in the environment necessary for further study of their removal, partition and ultimate fate. However, simultaneous analysis of compounds from different groups with quite different physico-chemical characteristics requires a compromise in the selection of experimental conditions, which in some cases are not the best conditions for all the analytes studied. In this article, an overview of analytical methodologies focusing on the simultaneous determination of acidic, neutral and basic compounds belonging to different therapeutical classes is presented. The state-of-the-art of LC-MS/MS for multi-class analysis is reviewed, highlighting the specific requirements for such analysis.     

Bifunctional Calix[4]arene Sensor for Pb(II) and Cr2O7 2− Ions

A readily available chromionophore 5,11,17,23-tetra-tert-butyl-25,27-bis(hydrazidecarbonylmethoxy)-26,28-dihydroxycalix[4]arene (HCC4) was employed as a chromogenic sensing probe selective for Pb(II) and Cr₂O₇ ^2? ions among a series of various ions such as Li(I), Na(I), K(I), Rb(I), Ba(II), Sr(II), Al(III), Cd(II), Co(II), Cu(II), Hg(II), Ni(II), Pb(II) and Zn(II) as well as Cr₂O₇ ^2?, CH₃CO₂ ^?, Br^?, Cl^?, F^?, I^?, ClO₄ ^? and NO₃ ^? that have been examined by UV-visible and fluorescence spectroscopic techniques. The HCC4 in DCM-MeCN system forms 2:1 (ligand-metal) complex with Pb(II). It also shows 2:1 stoichiometry with Cr₂O₇ ^2?. The complexation phenomenon has been confirmed by FTIR spectroscopy that favors the selective nature of HCC4 with Pb(II) and Cr₂O₇ ^2?. Thermal gravimetric analysis (TGA) also supports its utility in drastic conditions.     

Effects of various drugs on alcohol-induced oxidative stress in the liver

The major aim of this work was to investigate how alcohol-induced oxidative stress in combined chemotherapy changes the metabolic function of the liver in experimental animals. This research was conducted to establish how bromocriptine, haloperidol and azithromycin, applied to the experimental model, affected the antioxidative status of the liver. The following parameters were determined: reduced glutathione, activities of glutathione peroxidase, glutathione reductase, peroxidase, catalase, xanthine oxidase and lipid peroxidation intensity. Alanine transaminase was measured in serum. Alcohol stress (AO group) reduced glutathione and the activity of xanthine oxidase and glutathione peroxidase, but increased catalase and alanine transaminase activity. The best protective effect was achieved with the bromocriptine (AB1 group), while other groups had similar effects on the studied parameters.