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Bedside diagnosis of skin cancer remains a challenging task. The real-time non-invasive technology of optical coherence tomography (OCT) masters a high diagnostic accuracy in basal cell carcinoma (BCC) but a lower specificity in recognizing imitators and other carcinomas. We investigate the delicate signal of papillary dermis using an in-house developed ultrahigh resolution OCT (UHR-OCT) system with shadow compensation and a commercial multi-focus high resolution OCT (HR-OCT) system for clinical BCC imaging. We find that the HR-OCT system struggled to resolve the dark band signal of papillary dermis where the UHR-OCT located this in all cases and detected changes in signal width. UHR-OCT is able to monitor extension and position of papillary dermis suggesting a novel feature for delineating superficial BCCs in pursuit of a fast accurate diagnosis. Comprehensive studies involving more patients are imperative in order to corroborate results. This article is protected by copyright.

Bedside diagnosis of skin cancer remains a challenging task. The real-time noninvasive technology of optical coherence tomography (OCT) masters a high diagnostic accuracy in basal cell carcinoma (BCC) but a lower specificity in recognizing imitators and other carcinomas. We investigate the delicate signal of papillary dermis using an in-house developed ultrahigh resolution OCT (UHR-OCT) system with shadow compensation and a commercial multi-focus high resolution OCT (HR-OCT) system for clinical BCC imaging. We find that the HR-OCT system struggled to resolve the dark band signal of papillary dermis where the UHR-OCT located this in all cases and detected changes in signal width. UHR-OCT is able to monitor extension and position of papillary dermis suggesting a novel feature for delineating superficial BCCs in pursuit of a fast accurate diagnosis. Comprehensive studies involving more patients are imperative in order to corroborate results.

Myelin protein 2 (P2) is a peripheral membrane protein of the vertebrate nervous system myelin sheath, having possible roles in both lipid transport and 3D molecular organization of the multilayered myelin membrane. We extended our earlier crystallographic studies on human P2 and refined its crystal structure at an ultrahigh resolution of 0.72 Å in perdeuterated form and 0.86 Å in hydrogenated form. Characteristic differences in C–H…O hydrogen bond patterns were observed between extended β strands, kinked or ending strands, and helices. Often, side-chain C–H groups engage in hydrogen bonding with backbone carbonyl moieties. The data highlight several amino acid residues with unconventional conformations, including both bent aromatic rings and twisted guanidinium groups on arginine side chains, as well as non-planar peptide bonds. In two locations, such non-ideal conformations cluster, providing proof of local functional strain. Other ultrahigh-resolution protein structures similarly contain chemical groups, which break planarity rules. For example, in Src homology 3 (SH3) domains, a conserved bent aromatic residue is observed near the ligand binding site. Fatty acid binding protein (FABP) 3, belonging to the same family as P2, has several side chains and peptide bonds bent exactly as those in P2. We provide a high-resolution snapshot on non-ideal conformations of amino acid residues under local strain, possibly relevant to biological function. Geometric outliers observed in ultrahigh-resolution protein structures are real and likely relevant for ligand binding and conformational changes. Furthermore, the deuteration of protein and/or solvent are promising variables in protein crystal optimization.

We provide an unprecedented ultrahigh resolution picture of Earth’s gravity over all continents and numerous islands within ±60° latitude. This is achieved through augmentation of new satellite and terrestrial gravity with topography data and use of massive parallel computation techniques, delivering local detail at ~200 m spatial resolution. As such, our work is the first-of-its-kind to model gravity at unprecedented fine scales yet with near-global coverage. The new picture of Earth’s gravity encompasses a suite of gridded estimates of gravity accelerations, radial and horizontal field components, and quasi-geoid heights at over 3 billion points covering 80% of Earth’s land masses. We identify new candidate locations of extreme gravity signals, suggesting that the Committee on Data for Science and Technology standard for peak-to-peak variations in free-fall gravity is too low by about 40%. The new models are beneficial for a wide range of scientific and engineering applications and freely available to the public.

This program, entitled Advanced Technologies for Structural and Functional Optical Coherence Tomography, is a collaborative effort between investigators at the Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science and Research Laboratory of Electronics; Dr. David Boas, Associate Professor in Radiology, Harvard Medical School at the Massachusetts General Hospital, Martinos Center for Biomedical Imaging; and Dr. Jay Duker, Director, New England Eye Center, Professor and Chair of Ophthalmology, Tufts University School of Medicine. The objective of this program is to develop and apply advanced optical coherence tomography (OCT) technologies for ultrahigh resolution and functional imaging in biomedical applications., The original document contains color images.

The details of the fabrication and results of laboratory testing of the Ultra High Resolution Framing Camera containing onchip forward image motion compensation were presented to the SPIE at Airborne Reconaissance XXII in 1998. Three airborne flight tests of the Camera system have since been conducted with excellent results. This paper summarizes predicted performance for the Camera and presents some of the flight test imagery and data., The original document contains color images.

A framing camera incorporating an ultra high resolution CCD detector array comprised of 9,216 x 9,216 pixels is discussed. The detector array measures 8 x 8 centimeters and has been scaled to be fabricated in one piece on a 5inch diameter silicon wafer. Pixel size is 8.75 x 8.75 microns which gives 57 lp/mm resolution. The detector array features a two frame per second readout capability which allows collection of stereo imagery from very high V/H platforms. Image Motion Compensation is achieved by operating the frame readout clocks during the exposure interval in typical TDI fashion. The high geometric accuracy of pixel placement on the array yields a camera suitable for mapping, reconnaissance, space and astronomy applications. In this paper, measured detector array performance, detector array yield and overall camera performance are presented., Presented at the SPIE Conference on Airborne Reconnaissance (XXII), held in San Diego, CA on 21 July 1998. Pub. in the Proceedings of the SPIE Conference on Airborne Reconnaissance (XXII), v3431, Nov 1998. Editors: Wallace G. Fishell, Arthur A. Andraitis, Michael S. Fagan, Jerry D. Greer, and Mark C. Norton. The original document contains color images.

Research on this AASERT grant was focussed on the optical spectroscopy of trapped cold hydrogen for use as a spectroscopic tool and as a means of studying the gas. The grant supported research by two graduate students. During the grant an optical signal on the 1S - 2S transition in cold trapped hydrogen was observed, opening the way to a new form of ultra high resolution spectroscopy. The optical signal will also provide a valuable tool for manipulating a Bose condensate in hydrogen. The condensate can absorb two photons form a single running wave. The recoil is enough to sweep the atoms out of the trap, creating a new type of atom laser beam.