Genetic diversity and haplotype structure of 21 Y‐STRs,including nine noncore loci,in South Tunisian Population: Forensic relevance

Y chromosome STRs (Y‐STRs) are being used frequently in forensic laboratories. Previous studies of Y‐STR polymorphisms in different groups of the Tunisian population identified low levels of diversity and discrimination capacity (DC) using various commercial marker sets. This definitely limits the use of such systems for Y‐STRs genotyping in Tunisia. In our investigation on South Tunisia, 200 unrelated males were typed for the 12 conventional Y‐STRs included in the PowerPlex® Y System. Additional set of nine noncore Y‐STRs including DYS446, DYS456, DYS458, DYS388, DYS444, DYS445, DYS449, DYS710, and DYS464 markers were genotyped and evaluated for their potential in improving DC. Allele frequency, gene diversity, haplotype diversity (HD), and DC calculation revealed that DYS464 was the most diverse marker followed by DYS710 and DYS449 markers. The standard panel of 12 Y‐STRs (DC = 80.5%) and the nine markers were combined to obtain DC of 99%. Among the 198 different haplotypes observed, 196 haplotypes were unique (HD = 99.999). Out of the nine noncore set, six Y‐STRs (DYS458, DYS456, DYS449, DYS710, DYS444, and DYS464) had the greatest impact on enhancing DC. Our data provided putative Y‐STRs combination to be used for genetic and forensic applications.     

Substituent Effect on the Electronic Structure of Sulfines: Molecular Orbital Treatment

The electronic structure and ground state properties of the gaseous sulfine H₂CSO and some of its derivatives were studied at the RHF, MP2, and B3LYP levels. The calculations showed that the Z-isomer is more stable than the E-one and their difference in energy depends on their level of calculation, basis set, and substituent. The factors affecting the isomer stability are the electrostatic interactions, the steric factor, and π-electrons delocalization. The substituent has little effect on the geometry of the CSO moiety but greatly affects its charge distribution and polarizability. The ΔE value of the E- to Z-isomerization process via rotation of the S═O bond was calculated. The substituent has an appreciable effect on both the geometry and energy barrier of isomerization depending on its electronegativity, electrostatic attraction, and effect on π-delocalization over the molecule.     

Efficient oxidation of alcohols with tert-butyl hydroperoxide catalyzed by Mo(CO)6 supported on multiwall carbon nanotubes

Efficient oxidation of alcohols with tert-butyl hydroperoxide catalyzed by Mo(CO)₆ supported on multiwall carbon nanotubes modified with 4-aminopyridine is reported. The effect of various parameters such as catalyst amount, solvent and oxidant was studied. The catalyst, [Mo(CO)₅@APy-MWCNT], showed high activity not only in the oxidation of benzylic and linear alcohols but also in the oxidation of secondary alcohols. The catalyst can be reused several times without significant loss of its activity.     

Spectrophotometric Study of Complexation of Tri-Aza Dibenzosulfide and Dibenzosulfoxide Macrocyclic Compounds with Heavy Metal Ions

The complexation reactions between 7,10,13-triaza-1-thia-4,16-dioxa-20,24-dimethyl-2,3;17,18-dibenzo-cyclooctadecane-6,14-dione ( TTD ) and 7,10,13-triaza-1-sulfoxo-4,16-dioxa-20,24-dimethyl-2,3;17,18-dibenzo-cyclooctadecane-6,14-dione ( TSD ) macrocycles with Ag⁺, Cd²⁺, Cu²⁺, Pb²⁺, Sr²⁺, Tl⁺, and Zn²⁺ ions have been studied in ethanol and methanol solutions at 25°C. The complexes formed between macrocycles ( TTD ) and ( TSD ) with these metals cations had a stiochiometry of 1:1 and 1:2, respectively. The stability constants of the resulting complexes were determined and found to decrease in the order Cu²⁺ > Zn²⁺ > Ag⁺ > Tl⁺ > Cd²⁺ > Pb²⁺ > Sr²⁺ with macrocycle ( TTD ) and Tl⁺ > Zn²⁺ > Cd²⁺ > Pb²⁺ > Cu²⁺ > Ag⁺ > Sr²⁺ with macrocycle ( TSD ).     

Computational estimates of the gas-phase basicities,proton affinities and ionization potentials of the six isomers of dihydroxybenzoic acid

The gas-phase basicities (GBs), gas-phase proton affinities (PAs) and ionization potentials (IPs) of all six isomers of dihydroxybenzoic acid have been calculated using density functional theory at the B3LYP/6-311++G(2df,p)//B3LYP/6-31+G** level. A detailed conformational analysis of each isomer was performed, and the calculated thermodynamic properties were Boltzmann averaged over all conformations. Respectively, the GBs and the gas-phase PAs vary from 803.8 and 832.5?kJ?mol^?1 for the least basic species (3,5-DHB) to 830.1 and 861.4?kJ?mol^?1 for the most basic isomer (2,4-DHB). The reported GBs and gas-phase PAs of 2,3-DHB and 2,4-DHB, are in excellent agreement with previous experimental measurements. Agreement for the 2,5-DHB and 3,4-DHB isomers are not as good, but still close to or within the experimental error estimates. The calculated values for the GB and gas-phase PA of 2,6-DHB and especially 3,5-DHB are significantly outside the experimental error brackets. Repeating these calculations on the lowest energy conformation of each isomer at the MP2/6-311++G(2df,p)//MP2/6-31+G** level yielded significantly worse results. Our results indicate that protonation in all isomers takes place on the carboxylic sites. The vertical IPs vary from 8.14 eV for 2,5-DHB to 8.56 eV for 2,4-DHB.     

Computational study of matrix-peptide interactions in MALDI mass spectrometry: Interactions of 2,5- and 3,5-dihydroxybenzoic acid with the tripeptide valine-proline-leucine

The mechanism of matrix-to-analyte proton transfer in matrix-assisted laser desorption and ionization mass spectrometry (MALDI-MS) has been investigated computationally by modeling the matrix-analyte interaction of potential MALDI matrixes such as 2,5-dihydroxybenzoic acid (2,5-DHB) and 3,5-DHB with the tripeptide valine-proline-leucine (VPL). A combination of molecular dynamics/simulated annealing calculations followed by density functional theory geometry optimization using a reasonably large basis set has been done on a large number of clusters in an attempt to study the ionization energy of each matrix in the cluster environment and the intracluster proton transfer from the matrix to the tripeptide. The calculations show a substantial reduction in the IP for both matrixes in their cluster environments. In the 2,5-system, proton transfer can sometimes occur in the neutral clusters (preformed ions), whereas proton transfer in the cationic clusters, which is actually a double proton transfer, is spontaneous and exoergic. Even though it is more acidic from a thermodynamic perspective, the radical cation of 3,5-DHB is a less efficient proton donor to VPL. The thermodynamics of proton transfer in the cationic clusters is discussed in detail.     

Equilibrium conditions in laser-desorbed plumes: thermodynamic properties of alpha-cyano-4-hydroxycinnamic acid and protonation of amino acids

The equilibrium nature of a plume of laser desorbed material is explored through the application of a simple equilibrium model to the ion signals observed in 355 nm laser desorption/ionization mass spectra of mixtures of the MALDI matrix alpha-cyano-4-hydroxycinnamic acid (alphaCHCA) with the amino acids glycine, alanine, valine, isoleucine, and phenylalanine. In these studies it is found that there are systematic and predictable increases in the relative yield of protonated amino acid with increases in amino acid gas-phase basicity. In addition, the thermodynamic values extracted from the equilibrium plot are shown to be in good agreement with values obtained from computational investigation of plausible alphaCHCA proton donor species. These results are supportive of a picture wherein the laser-desorbed material is viewed as a dense plume in which facile charge transfer occurs leading, ultimately, to a thermodynamically equilibrated distribution of proton donor and proton acceptor species.     

Synthesis and characterizations of various polyvinyl pyrrolidon/hydroxyl ethyl methacrylate nanocomposite hydrogels as drug delivery systems

Using polymer hydrogels and nanocomposites hydrogels still promising materials for many applications. Polyvinyl pyrrolidone (PVP) has been used with various polymers synthetic and natural for different applications. In this study PVP and hydroxyl ethyl methacrylate (HEMA) copolymer hydrogels were prepared by the aid of gamma radiation and the PVP/HEMA nanocomposite hydrogels were obtained by in situ adsorption and reduction method of iron salts and silver nitrates (AgNO₃) to form PVP/HEMA-Fe₃O₄ and PVP/HEMA-Ag nanocomposites. The prepared hydrogels and the formed nanoparticles were studied by various techniques; FTIR, TEM, SEM and also the gel content and swelling behavior were evaluated. The prepared hydrogels and nanocomposites hydrogels were examined as drug delivery systems for Ciprofloxacin HCl as model drug. The PVP/HEMA-Fe₃O₄ nanocomposite gave the suitable load and release behavior towards Ciprofloxacin HCl.     

New Approaches for the Synthesis of Thiazoles and Their Fused Derivatives with Antimicrobial Activities

The 2‐ethoxy carbonyl methylene thiazol‐4‐one ( 3 ) reacts with acetophenone ( 4 ) to give the ethyl 2‐(4‐oxo‐4,5‐dihydro‐thiazol‐2‐yl)‐3‐phenyl‐2‐butenoate ( 5 ). The reactivity of the latter product towards aromatic aldehydes 6a‐d , cyanomethylene reagents 9a,b , aromatic aldehydes 13a‐d , phenylisothiocyanate ( 16 ), elemental sulfur and aromatic amines ( 20a‐c ) was studied to give arylidene, pyridine, thiophene and anilide derivatives. Some of the newly synthesized derivatives were used to synthesize fused derivatives. The antimicrobial activities of the newly synthesized products were tested in vitro for antimicrobial activity against two bacterial isolates, one saprophytic (Escherichia coli) and the other parasitic (Xanthomonas citri) and for antifungal activity against one saprophytic (Aspergillus fumigatus) and two phytopathogenics (Rhizoctonia solani and Fusarium oxysporum).