Was Frozen Mammoth or Giant Ground Sloth Served for Dinner at The Explorers Club?

Accounts of woolly mammoths (Mammuthus primigenius) preserved so well in ice that their meat is still edible have a long history of intriguing the public and influencing paleontological thought on Quaternary extinctions and climate, with some scientists resorting to catastrophism to explain the instantaneous freezing necessary to preserve edible meat. Famously, members of The Explorers Club purportedly dined on frozen mammoth from Alaska, USA, in 1951. This event, well received by the press and general public, became an enduring legend for the Club and popularized the notorious annual tradition of serving rare and exotic food at Club dinners that continues to this day. The Yale Peabody Museum holds a sample of meat preserved from the 1951 meal, interestingly labeled as a South American giant ground sloth (Megatherium), not mammoth. We sequenced a fragment of the mitochondrial cytochrome-b gene and studied archival material to verify its identity, which if genuine, would extend the range of Megatherium over 600% and alter our views on ground sloth evolution. Our results indicate that the meat was not mammoth or Megatherium but green sea turtle (Chelonia mydas). The prehistoric dinner was likely an elaborate publicity stunt. Our study emphasizes the value of museums collecting and curating voucher specimens, particularly those used for evidence of extraordinary claims.

Clinical Implementation of a Proton Dose Verification System Utilizing a GPU Accelerated Monte Carlo Engine.

PURPOSE: To develop a clinical infrastructure that allows for routine Monte Carlo dose calculation verification of spot scanning proton treatment plans and includes a simple biological model to aid in normal tissue protection. MATERIALS AND METHODS: A graphical processing unit accelerated Monte Carlo dose engine was used as the calculation engine for dose verification on spot scanning proton plans. An infrastructure was built around this engine that allows for seamless exporting of treatment plans from the treatment planning system and importing of dose distribution from the Monte Carlo calculation via DICOM (digital imaging and communications in medicine). An easy-to-use Web-based interface was developed so that the application could be run from any computer. In addition to the standard relative biological effectiveness = 1.1 for proton therapy, a simple linear equation dependent on dose-weighted linear energy transfer was included. This was used to help detect possible high biological dose in critical structures. RESULTS: More than 270 patients were treated at our proton center in the first year of operation. Because most plans underwent multiple iterations before final approval, more than 1000 plans have been run through the system from multiple users with minimal downtime. The average time from plan export to importing of the Monte Carlo doses was less than 15 minutes. Treatment plans have been modified based on the nominal Monte Carlo dose or the biological dose. CONCLUSION: Monte Carlo dose calculation verification of spot scanning proton treatment plans is feasible in a clinical environment. The 3-dimensional dose verification, particularly near heterogeneities, has resulted in plan modifications. The biological dose data provides actionable feedback for end of range effects, especially in pediatric patients.

Trinuclear copper(I) complex containing 3,4,9,10,15,16-hexamethyl-1,6,7,12,13,18-hexaazatrinaphthylene: a structural, spectroscopic, and computational study.

The compound [(Cu(PPh(3))(2))(3)(HATNMe(6))](BF(4))(3) has been synthesized and characterized by X-ray crystallography, resonance Raman spectroscopy, and density functional theory (DFT) calculations. The X-ray structure of solvated [(Cu(PPh(3))(2))(3)(HATNMe(6))](BF(4))(3) [rhombohedral, R3, a = b = 21.6404(4) A, c = 53.188(3) A, alpha = beta = 90 degrees, gamma = 120 degrees] shows that the HATNMe(6) ligand is very slightly twisted. The electronic absorption spectrum of the complex in chloroform shows two bands in the visible region attributed to ligand-centered (LC) and metal-to-ligand charge-transfer (MLCT) transitions, respectively. Time-dependent DFT calculations show good agreement with experiment, with two MLCT and one LC transition predicted in the visible region (641, 540, and 500 nm). Resonance Raman spectra of the complex using discrete excitation energies between 647 and 406 nm showed a variation in enhancement patterns consistent with at least two distinct transitions. The absolute Raman cross sections have been evaluated and, through a wavepacket analysis, the amount of distortion along each vibrational mode across the Franck-Condon surface is established from the calculated dimensionless displacement (Delta) values as well as other electronic parameters. The pattern of Delta values shows good agreement with the observed calculated modes, with the MLCT transition, showing much larger Delta values for outer ring modes such as nu(93) and nu(205) than in the LC transition. This is consistent with the molecular orbitals involved in the two transitions; the donor orbitals for the LC transition have similar outer-ring bonding characteristics compared to the MLCT transition, which has no donor orbital bonding characteristics on the ligand because the donor molecular orbitals are dpi orbitals.

Vibrational spectroscopy and quantum chemical studies of 1,6,7,12,13,18-hexaazatrinaphthylene and related compounds.

The spectral properties of 1,6,7,12,13,18-hexaazatrinaphthylene (HATN) and a number of related compounds are modeled using density functional theory, B3LYP. The calculations predict the frequencies with mean absolute deviation of 6 cm(-1) and there is little improvement on going to basis sets larger than 6-31 G(d). The substituent effects on the observed spectra are modeled effectively in both frequency shifts and relative intensities. The electronic properties may be predicted using TD-DFT and these are in very good agreement, in terms of transition energies and intensities, with the experimental data.

Repeated injections of sulpiride into the medial prefrontal cortex induces sensitization to cocaine in rats.

RATIONALE: Recent studies have suggested that the medial prefrontal cortex (mPFC) plays an important role in the development of sensitization to cocaine. In particular, a recent report proposed that sensitization is associated with a decreased dopamine D(2) receptor function in the mPFC. The present study was designed to further examine the involvement of mPFC dopamine D(2) receptors in cocaine sensitization. OBJECTIVES: The experiments described below sought to determine the effects of acute or repeated intra-mPFC injections of the dopamine D(2) antagonist sulpiride on subsequent motor-stimulant and nucleus accumbens dopamine responses to cocaine. METHODS: Rats received bilateral cannulae implants above the ventral mPFC for microinjections and above the nucleus accumbens for in vivo microdialysis. Initial studies examined the effects of intra-mPFC sulpiride pretreatment on the acute motor-stimulant and nucleus accumbens dopamine responses to cocaine. Follow-up studies determined the effects of repeated intra-mPFC sulpiride injections on subsequent behavioral and nucleus accumbens dopamine responses to a cocaine challenge. RESULTS: Intra-mPFC sulpiride enhanced the cocaine-induced increases in motor activity and dopamine overflow in the nucleus accumbens. Repeated intra-mPFC sulpiride induced behavioral and neurochemical cross-sensitization to cocaine. CONCLUSIONS: The data support previous findings that sensitization is associated with a decrease in dopamine D(2) receptor function in the mPFC.