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A molecular dynamics investigation of guanine quadruple helices based on classical force fields is done by studying the dependence of the helical conformation on different compositional factors like lengths of the G4 wire, the incorporation into the helix channel of alkali ions of various species and in varying amount. The empirical outcomes indicate that monovalent alkali cations help the stability of the quadruplex arrangement against disruption on the few nanoseconds time scale in the order of increasing van der Waals radius.

First-principle study of the electronic and conduction properties of infinite G4 wires was reported, which showed that the pi-pi coupling among stacked planar tetrads is insufficient to induce the formation of dispersive bands in the wires. These results concluded that G4 wires were viable as DNA based conductors for nanoscale molecular electronics.

NMR spectroscopic studies of the effect of substitution of L-nucleotides for D-nucleotides in the duplex d(G-C-G-(L)T-G-C-G).d(C-G-C-A-C-G-C) and subsequent studies on the solution structure show that the structure exhibits a reaction between the aromatic rings of the (L)T4.A11 and G3.C12 base pairs. This interaction explains the unique thermodynamic properties of the duplex. The structure shows a similarity with that of B-DNA with all sugar adopting an S-type pucker.

The effect of seasonal changes in soil conditions on pressure-driven soil-gas entry rates and the consistent underpredictions of these rates were investigated. The westernmost of two basement structures located in the Santa Cruz Mountains, California were subjected to controlled artificial depressurization. Seasonal changes in soil moisture and permeability did not cause measurable changes in soil-gas and radon transport.

A quantitative study using several selfcomplementary oligonucleotides containing 5'-TA and 5'-AT residues and various flanking sequences was performed to determine the effect of DNA sequences on furocoumarin derivatives' photoreaction. Rate constants for the photobinding process for each fragment were examined based on the thermodynamic constant for the noncovalent binding between each psoralen to each DNA sequence. DNA sequence was found to influence the degree of photoreaction. Type 5'-(GTAC)n sequences was found to be particularly reactive to all furocoumarins, while 5'-TATA displayed lower photobinding rates using monofunctional psoralens.

The article explains the ab initio optical absorption spectra of various size-expanded xDNA base assemblies. The optical response is found to get highly affected by the modifications of the frontier electron orbitals.

A study on electronic structure of periodic quadruple helix guanine wire with mimic G4-DNA molecules as a function of the stacking distance between consecutive planes by means of first density functional theory calculations was conducted. The findings indicated that efficient band conduction for both holes and electrons could be supported by such wire for stacking distance below 2.6 Angstrom, which implies a huge axial deformation with respect to double and quadruple helices in solutions and in crystals.

This paper describes an analysis of historical surface wind data for the small country of Eritrea, in northeastern Africa. Winds in this region are directed by summer and winter monsoons in addition to diurnal land - sea effects. An analysis of national Eritrean and historical Italian wind records indicated marginal wind resources in the central highlands near the Eritrean capital of Asmera. An analysis of wind speed records recorded at two sites in the southern port city of Aseb indicate mean annual 10-m wind speeds of 9.5 m [s.sup.-1] at the windier site. Surface wind speed records for the Red Sea suggest that similar potential may be found along the lower 200 km of the Eritrean coastline. Based on these findings, wind-generated electricity in this region should be substantially cheaper than the current supply generated from imported diesel.