Photomosaics: Lincoln

Jigsaw puzzle entitled œLincoln. One of œPhotomosaics series by Robert Silvers. Incorporates thousands of miniature19th century photographs to form a computer-generated bust portrait of Abraham Lincoln. Finished size of assembled puzzle is 28 1/2 X 20 1/4 . Issued ca. 1998 by Buffalo Games. In sealed, decorative box. [See also #4841; poster depicting identical image - fc 1/18/98]. artwork by Robert Silvers (American, 1968-present?), produced by Buffalo Games Inc (American, 1986-present) with the copyright held by Runaway Technology Inc. (American, 1996-present)https://scholarsjunction.msstate.edu/fvw-artifacts/4701/thumbnail.jp

Collisional depolarization of state selected (J,M J ) BaO A 1Σ+ measured by optical–optical double resonance

The optical–optical double resonance (OODR) technique is used to investigate the change in magnetic quantum number (M) a state selected molecule undergoes on collision with other molecules. A first linearly polarized dye laser prepares A  1Σ+BaO(v = 1) in the J = 1, M = 0 sublevel. The extent of collisional transfer to other M sublevels of both J = 1 and J = 2 is then probed by a second polarized dye laser which induces fluorescence from the C  1Σ+ state. Elastic collisions (ΔJ = 0) between BaO (A  1Σ+) and CO2 are observed to change M from 0 to ±1 leaving J unchanged. The total elasticM‐changing cross section is σΔM CO2 = 8.4±2.4 Å2. Inelastic collisions (ΔJ = +1’ which transfer molecules to j = 2 also cause M changes. with both Ar and CO2 as collision partners. M, the s p a c e‐f i x e d projection of J, is found to be neither conserved nor randomized. Quantum atom–diatom collision models with quantization axis along the relative velocity vector are considered. Transition amplitudes in this system are evaluated using the l‐dominant and CS approximations

3D MAS NMR Experiment Utilizing Through-Space

We demonstrate a novel 3D NNC magic angle spinning NMR experiment that generates ¹⁵N–¹⁵N internuclear contacts in protein systems using an optimized ¹⁵N–¹⁵N proton assisted recoupling (PAR) mixing period and a ¹³C dimension for improved resolution. The optimized PAR condition permits the acquisition of high signal-to-noise 3D data that enables backbone chemical shift assignments using a strategy that is complementary to current schemes. The spectra can also provide distance constraints. The utility of the experiment is demonstrated on an M₀Aβ₁₋₄₂ fibril sample that yields high-quality data that is readily assigned and interpreted. The 3D NNC experiment therefore provides a powerful platform for solid-state protein studies and is broadly applicable to a variety of systems and experimental conditions.National Institute of Biomedical Imaging and Bioengineering (U.S.) (Grant EB-001960)National Institute of Biomedical Imaging and Bioengineering (U.S.) (Grant EB-002026

Photomosaics : putting pictures in their place

Thesis (M.S.)--Massachusetts Institute of Technology, Program in Media Arts & Sciences, 1996.Includes bibliographical references (p. 91-92).by Robert S. Silvers.M.S

High Resolution Structural Characterization of Aβ₄₂ Amyloid Fibrils by Magic Angle Spinning NMR

National Institute of Biomedical Imaging and Bioengineering (U.S.) (EB-003151)National Institute of Biomedical Imaging and Bioengineering (U.S.) (EB-001960)National Institute of Biomedical Imaging and Bioengineering (U.S.) (EB-002026

19F-labeling of the adenine H2-site to study large RNAs by NMR spectroscopy

In comparison to proteins and protein complexes, the size of RNA amenable to NMR studies is limited despite the development of new isotopic labeling strategies including deuteration and ligation of differentially labeled RNAs. Due to the restricted chemical shift dispersion in only four different nucleotides spectral resolution remains limited in larger RNAs. Labeling RNAs with the NMR-active nucleus [superscript 19]F has previously been introduced for small RNAs up to 40 nucleotides (nt). In the presented work, we study the natural occurring RNA aptamer domain of the guanine-sensing riboswitch comprising 73 nucleotides from Bacillus subtilis. The work includes protocols for improved in vitro transcription of 2-fluoroadenosine-5′-triphosphat (2F-ATP) using the mutant P266L of the T7 RNA polymerase. Our NMR analysis shows that the secondary and tertiary structure of the riboswitch is fully maintained and that the specific binding of the cognate ligand hypoxanthine is not impaired by the introduction of the [superscript 19]F isotope. The thermal stability of the [superscript 19]F-labeled riboswitch is not altered compared to the unmodified sequence, but local base pair stabilities, as measured by hydrogen exchange experiments, are modulated. The characteristic change in the chemical shift of the imino resonances detected in a 1H,15N-HSQC allow the identification of Watson–Crick base paired uridine signals and the [superscript 19]F resonances can be used as reporters for tertiary and secondary structure transitions, confirming the potential of [superscript 19]F-labeling even for sizeable RNAs in the range of 70 nucleotides.Deutsche Forschungsgemeinschaft (collaborative research center: SFB902

Lipid bilayer-bound conformation of an integral membrane beta barrel protein by multidimensional MAS NMR

The human voltage dependent anion channel 1 (VDAC) is a 32 kDa β-barrel integral membrane protein that controls the transport of ions across the outer mitochondrial membrane. Despite the determination of VDAC solution and diffraction structures, a structural basis for the mechanism of its function is not yet fully understood. Biophysical studies suggest VDAC requires a lipid bilayer to achieve full function, motivating the need for atomic resolution structural information of VDAC in a membrane environment. Here we report an essential step toward that goal: extensive assignments of backbone and side chain resonances for VDAC in DMPC lipid bilayers via magic angle spinning nuclear magnetic resonance (MAS NMR). VDAC reconstituted into DMPC lipid bilayers spontaneously forms two-dimensional lipid crystals, showing remarkable spectral resolution (0.5–0.3 ppm for [superscript 13]C line widths and <0.5 ppm [superscript 15]N line widths at 750 MHz). In addition to the benefits of working in a lipid bilayer, several distinct advantages are observed with the lipid crystalline preparation. First, the strong signals and sharp line widths facilitated extensive NMR resonance assignments for an integral membrane β-barrel protein in lipid bilayers by MAS NMR. Second, a large number of residues in loop regions were readily observed and assigned, which can be challenging in detergent-solubilized membrane proteins where loop regions are often not detected due to line broadening from conformational exchange. Third, complete backbone and side chain chemical shift assignments could be obtained for the first 25 residues, which comprise the functionally important N-terminus. The reported assignments allow us to compare predicted torsion angles for VDAC prepared in DMPC 2D lipid crystals, DMPC liposomes, and LDAO-solubilized samples to address the possible effects of the membrane mimetic environment on the conformation of the protein. Concluding, we discuss the strengths and weaknesses of the reported assignment approach and the great potential for even more complete assignment studies and de novo structure determination via [superscript 1]H detected MAS NMR.National Institutes of Health (U.S.) (Grant EB001960)National Institutes of Health (U.S.) (Grant EB002026

Esophageal Perforation Due to a Calcium Supplement Tablet

Pill-induced esophagitis due to calcium supplements is extremely uncommon. We present a 60-year-old female patient with pill-induced esophageal perforation complicated by mediastinal abscess and esophago-pleural fistula following ingestion of a single over-the-counter “bone supplement” tablet containing mainly calcium

The 25th Anniversary of the Baby Doe Rules: Perspectives from the Fields of Law, Health Care, Ethics, and Disability Policy

A highly publicized and controversial case involving the withholding of medical treatment from a “Baby Doe” with Down syndrome gave rise in 1984 to the federal law known as the Baby Doe Rules, which went into effect the following year. The law conditions the grant of federal funds for any state’s child protective services program on the state’s assurance that it can respond to reports of medical neglect, which may include the withholding of medical treatment from disabled infants with life-threatening conditions. Leading scholars and practitioners from the fields of health care, law, ethics, and disability policy who are experts in the field of neonatal medicine and decision-making involving very premature and other medically at-risk infants gathered to provide thoughtful commentary and debate on the occasion of the 25th Anniversary of the Baby Doe Rules. The Georgia State University Law Review will publish a symposium volume on the topic in Fall 2009