Biomedical subjects

J O Jensen

Publications and source records attributed to J O Jensen.

4 recordsLinked to original sources

PubMed2002

Submillimeter-wave phonon modes in DNA macromolecules.

A detailed investigation of phonon modes in DNA macromolecules is presented. This work presents experimental evidence to confirm the presence of multiple dielectric resonances in the submillimeter-wave spectra (i.e., approximately 0.01-10 THz) obtained from DNA samples. These long-wave (i.e., approximately 1-30 cm(-1)) absorption features are shown to be intrinsic properties of the particular DNA sequence under study. Most importantly, a direct comparison of spectra between different DNA samples reveals a large number of modes and a reasonable level of sequence-specific uniqueness. This work establishes the initial foundation for the future use of submillimeter-wave spectroscopy in the identification and characterization of DNA macromolecules.

Biophysics↗

PubMed2001

Vibrational frequencies and structural determinations of 1,4-thioxane.

We present a detailed analysis of the structure and infrared spectra of 1,4-thioxane. The vibrational frequencies of the 1,4-thioxane molecule were analyzed using standard quantum chemical techniques. Frequencies were calculated at the MP2 and DFT levels of theory using the standard 6-31G* basis set. The structural transformation of the chemical agent bis (2-chloroethyl) sulfide (HD, mustard gas) and the related symmetry to a previously study compound(4) makes the symmetry of the 1,4-thioxane molecule an interesting candidate for study. The molecule exists normally in a Cs configuration similar to the chair form of cyclohexane. High-energy forms of 1,4-thioxane with C1 and C2 symmetry also exist.

Chromatography, Gas↗

PubMed1978

Alveolar osteitis (dry socket)--a review.

The literature on "dry socket" is reviewed. The diagnosis, incidence and predisposing factors are discussed in relation to its aetiology. Treatment regimes are outlined; in particular, the use of anti-fibrinolytic drugs.

Adult↗

PubMedDate not supplied

Millimeter wave-induced vibrational modes in DNA as a possible alternative to animal tests to probe for carcinogenic mutations.

Developing methods for alternative testing is increasingly important due to dwindling funding resources and increasing costs associated with animal testing and legislation. We propose to test the feasibility of a new and novel method for detecting DNA mutagenesis using millimeter wave spectroscopy. Although millimeter wave spectroscopy has been known since the 1950s, the cost was prohibitive and studies did not extend to large biological proteins such as DNA. Recent advances have made this technology feasible for developing laboratory and field equipment. We present preliminary findings for lesion-induced vibrational modes in DNA observed from 80 to 1000 gigahertz (GHz). These findings suggest that there are vibrational modes that can be used as identification resonances. These modes are associated with localized defects of the DNA polymers. They are unique for each defect/lesion, and should be easy to detect. We described a field-detecting detector based on the local modes.

Animal Testing Alternatives↗