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Jeff White

Publications and source records attributed to Jeff White.

4 recordsLinked to original sources
PubMed2005

Terahertz wide aperture reflection tomography.

We describe a powerful imaging modality for terahertz (THz) radiation, THz wide aperture reflection tomography (WART). Edge maps of an object's cross section are reconstructed from a series of time-domain reflection measurements at different viewing angles. Each measurement corresponds to a parallel line projection of the object's cross section. The filtered backprojection algorithm is applied to recover the image from the projection data. To our knowledge, this is the first demonstration of a reflection computed tomography technique using electromagnetic waves. We demonstrate the capabilities of THz WART by imaging the cross sections of two test objects.

Journal Article↗
PubMed2004

Improved synthesis and deployment of (2S,3R)-2-(2Z,5Z-octadienyl)-3-nonyloxirane, a pheromone of the pink moth, Lymantria mathura.

We report two new syntheses of (2S,3R)-2-(2Z,5Z-octadienyl)-3-nonyloxirane, the main sex pheromone component of the pink moth, Lymantria mathura. The key step in the first route was the construction of (Z,Z)-1-bromo-1,4-heptadiene (6), which was coupled in the final step with 2-iodomethyl-3-nonyloxirane 4 via a Grignard reaction. The second approach employed alkylation of 1,4-heptadiynyllithium with epoxy triflates 7 in ether/hexane and provided the pheromone in >/=37% overall yield from alcohol 2. The 4:1 ratio of pheromone enantiomers, reportedly the most attractive to pink moth males, can be directly crafted from appropriately selected Sharpless asymmetric epoxidation conditions.

Animals↗
PubMedDate not supplied

A salutary tale of mistaken identity in testicular cancer.

This case report illustrates the importance of not relying on imaging alone. A 26-year-old patient underwent an orchidectomy for mature teratoma; however, as he had abdominal lymphadenopathy, he was treated with 2 cycles of chemotherapy followed by retroperitoneal lymph node dissection. The abdominal histology revealed mature teratoma and he remained on intense surveillance. Three years later, computerized tomography (CT) indicated he had lung lesions and left hilar lymphadenopathy and, despite normal tumor markers, he was thought to have relapsed. He was treated with 2 cycles of second-line chemotherapy but there was no change in the lung lesions. He underwent a CT-guided biopsy which diagnosed sarcoidosis. He was kept under observation by the respiratory physicians and remains well. Sarcoidosis is commonly associated with lymphoma among other malignancies. In the Mayo series, they concluded there was a strong association between sarcoidosis and teratoma but cautioned against a causal relationship as both diseases are rare and found in the same age group. This case report reminds us to always consider the differential diagnoses, particularly if the imaging does not fit the rest of the clinical picture, and when in doubt obtain histology prior to treatment.

Adult↗