Microsatellite analysis for determination of the mutagenicity of extremely low-frequency electromagnetic fields and ionising radiation in vitro.

Extremely low-frequency electromagnetic fields (ELF-EMF) have been reported to induce lesions in DNA and to enhance the mutagenicity of ionising radiation. However, the significance of these findings is uncertain because the determination of the carcinogenic potential of EMFs has largely been based on investigations of large chromosomal aberrations. Using a more sensitive method of detecting DNA damage involving microsatellite sequences, we observed that exposure of UVW human glioma cells to ELF-EMF alone at a field strength of 1 mT (50 Hz) for 12 h gave rise to 0.011 mutations/locus/cell. This was equivalent to a 3.75-fold increase in mutation induction compared with unexposed controls. Furthermore, ELF-EMF increased the mutagenic capacity of 0.3 and 3 Gy gamma-irradiation by factors of 2.6 and 2.75, respectively. These results suggest not only that ELF-EMF is mutagenic as a single agent but also that it can potentiate the mutagenicity of ionising radiation. Treatment with 0.3 Gy induced more than 10 times more mutations per unit dose than irradiation with 3 Gy, indicating hypermutability at low dose.

Listening to lanthanide complexes: Determination of the intrinsic luminescence quantum yield by nonradiative relaxation

The photophysical properties of lanthanide complexes have been studied extensively; however, fundamental parameters such as the intrinsic quantum yield as well as radiative and nonradiative decay rates are difficult or even impossible to measure experimentally. Herein, a photoacoustic (PA) method is proposed to determine the intrinsic quantum yield of lanthanide complexes with lifetimes in the order of milliseconds. This method is used to determine the intrinsic quantum yields for europium (III)-containing metallomesogens as well as terbium(III) complexes. The results show that the PA signal is sensitive to both the lifetime and the ratio of the fast-to-slow heat component of the samples. It is found that there is an efficient ligand sensitization and a moderate intrinsic quantum yield for the complexes. The intrinsic quantum yield of Eu3+ in the metallomesogens exhibits an obvious increase upon the isotropic liquid to smectic A transition. The proposed PA method is quite simple, and con contribute to a clearer understanding of the photophysical processes in luminescent lanthanide complexes.

Neoteric optical media for refractive index determination of gems and minerals

Refractive index determination of minerals and gems often requires their immersion in fluids with the same refractive index. However, these natural materials frequently have refractive indices above the ranges of common organic solvents. Most available high refractive index immersion materials are solid at room temperature, toxic, noxious, corrosive, carcinogenic, or any combination thereof. Since the physical properties of ionic liquids can be tuned by varying the cation and/or anion, we have developed immersion fluids for mineralogical studies which are relatively benign. We report here the syntheses of a range of ionic liquids ( many novel) based on the 1-alkyl-3-methylimidazolium cation, which all have refractive indices greater than 1.4, and can be used as immersion fluids for optical mineralogy studies. We further show that for a series of ionic liquids with the same anion, the refractive indices can be adjusted by systematic changes in the cation.

Evaluation of a Microfluidic Device for the Electrochemical Determination of Halide Content in Ionic Liquids

A microfluidic device designed for electrochemical studies on a microliter scale has been utilized for the examination of impurity levels in ionic liquids (ILs). Halide impurities are common following IL synthesis, and this study demonstrates the ability to quantify low concentrations of halide in a range of ILs to levels of similar to 5 ppm, even in ILs not currently measurable using other methods such as ion chromatography. To validate the mixer device, the electrochemistry of ferrocene was also examined and compared with spectroscopic and bulk electrochemistry measurements. An automated

Electrochemical Determination of Manganese Solubility in Mercury via Amalgamation and Stripping in the Room Temperature Ionic Liquid n-Hexyltriethylammonium Bis(trifluoromethanesulfonyl)imide, [N-6,N-2,N-2,N-2][NTf2]

The solubility of manganese in mercury was determined electrochemically via amalgamation and stripping in the room temperature ionic liquid n-hexyltriethylammonium bis(trifluoromethanesulfonyl)imide, [N-6,N-2,N-2,N-2][NTf2]. A hemispherical mercury electrode was made by electrodepositing mercury onto a planar platinum microelectrode. Cyclic voltammetry of Mn2+ in [N-6,N-2,N-2,N-2][NTf2] at the mercury microhemisphere electrode was investigated at temperatures of 298, 303 and 313 K. The solubility of Mn in Hg was determined on the basis of the charge under the reduction peak (Mn2+ --> Mn-0) and the corresponding reoxidation.

Nonisothermal moisture transport in hygroscopic building materials: modeling for the determination of moisture transport coefficients

A mathematical model for calculating the nonisothermal moisture transfer in building materials is presented in the article. The coupled heat and moisture transfer problem was modeled. Vapor content and temperature were chosen as principal driving potentials. The coupled equations were solved by an analytical method, which consists of applying the Laplace transform technique and the Transfer Function Method. A new experimental methodology for determining the temperature gradient coefficient for building materials was also proposed. Both the moisture diffusion coefficient and the temperature gradient coefficient for building material were experimentally evaluated. Using the measured moisture transport coefficients, the temperature and vapor content distribution inside building materials were predicted by the new model. The results were compared with experimental data. A good agreement was obtained.

Graphical determination of network limits for wind power integration

A graphical method is presented for determining the capability of individual system nodes to accommodate wind power generation. The method is based upon constructing a capability chart for each node at which a wind farm is to be connected. The capability chart defines the domain of allowable power injections at the candidate node, subject to constraints imposed by voltage limits, voltage stability and equipment capability limits being satisfied. The chart is first derived for a two-bus model, before being extended to a multi-node power system. The graphical method is employed to derive the chart for a two-node system, as well as its application to a multi-node power system, considering the IEEE 30-bus test system as a case study. Although the proposed method is derived with the intention of determining the wind farm capacity to be connected at a specific node, it can be used for the analysis of a PQ bus loading as well as generation.

Discovery of substituted maleimides as liver X receptor agonists and determination of a ligand-bound crystal structure

Substituted 3-(phenylamino)-1H-pyrrole-2,5-diones were identified from a high throughput screen as inducers of human ATP binding cassette transporter A1 expression. Mechanism of action studies led to the identification of GSK3987 (4) as an LXR ligand. 4 recruits the steroid receptor coactivator-1 to human LXR alpha and LXRP with EC(50)s of 40 nM, profiles as an LXR agonist in functional assays, and activates LXR though a mechanism that is similar to first generation LXR agonists.

A survey of sidedness in Northern Irish schoolchildren: The interaction of sex, age, and task

The study examined lateral preference in use of hands, feet, eyes, and ears in a group of nearly 5000 schoolchildren in Northern Ireland. Performance tests were carried out by student teachers during their school-based work in 2002 and data were submitted on-line. Six tasks were used-writing, throwing a ball, kicking a ball, hopping, listening to quiet sounds, and looking through a cardboard tube. There was right bias in every task but the extent of it differed between tasks. Males were generally less right biased than females, and younger children less than older ones; for hearing, the changes with age were markedly different in the two sexes, with females showing a strong increase in right bias but males showing none. These observational results do little to illuminate the reasons for the patterns observed.