PASADENA Hyperpolarization of Succinic Acid for MRI and NMR Spectroscopy

We use the PASADENA (parahydrogen and synthesis allow dramatically enhanced nuclear alignment) method to achieve ^(13)C polarization of ∼20% in seconds in 1-^(13)C-succinic-d_2 acid. The high-field ^(13)C multiplets are observed as a function of pH, and the line broadening of C1 is pronounced in the region of the pK values. The ^2J_(CH), ^3J_(CH), and ^3J_(HH) couplings needed for spin order transfer vary with pH and are best resolved at low pH leading to our use of pH ∼3 for both the molecular addition of parahydrogen to 1-^(13)C-fumaric acid-d_2 and the subsequent transfer of spin order from the nascent protons to C1 of the succinic acid product. The methods described here may generalize to hyperpolarization of other carboxylic acids. The C1 spin−lattice relaxation time at neutral pH and 4.7 T is measured as 27 s in H_2O and 56 s in D_2O. Together with known rates of succinate uptake in kidneys, this allows an estimate of the prospects for the molecular spectroscopy of metabolism

VETA-1 x ray detection system

The alignment and X-ray imaging performance of the Advanced X-ray Astrophysics Facility (AXAF) Verification Engineering Test Article-I (VETA-I) was measured by the VETA-I X-Ray Detection System (VXDS). The VXDS was based on the X-ray detection system utilized in the AXAF Technology Mirror Assembly (TMA) program, upgraded to meet the more stringent requirements of the VETA-I test program. The VXDS includes two types of X-ray detectors: (1) a High Resolution Imager (HRI) which provides X-ray imaging capabilities, and (2) sealed and flow proportional counters which, in conjunction with apertures of various types and precision translation stages, provide the most accurate measurement of VETA-I performance. Herein we give an overview of the VXDS hardware including X-ray detectors, translation stages, apertures, proportional counters and flow counter gas supply system and associated electronics. We also describe the installation of the VXDS into the Marshall Space Flight Center (MSFC) X-Ray Calibration Facility (XRCF). We discuss in detail the design and performance of those elements of the VXDS which have not been discussed elsewhere; translation systems, flow counter gas supply system, apertures and thermal monitoring system

Resistance to autosomal dominant Alzheimer's disease in an APOE3 Christchurch homozygote: a case report.

We identified a PSEN1 (presenilin 1) mutation carrier from the world's largest autosomal dominant Alzheimer's disease kindred, who did not develop mild cognitive impairment until her seventies, three decades after the expected age of clinical onset. The individual had two copies of the APOE3 Christchurch (R136S) mutation, unusually high brain amyloid levels and limited tau and neurodegenerative measurements. Our findings have implications for the role of APOE in the pathogenesis, treatment and prevention of Alzheimer's disease

Electron Identification with a Prototype of the Transition Radiation Tracker for the ATLAS experiment

A prototype of the Transition Radiation Tracker (TRT) for the ATLAS detector at the LHC has been built and tested. The TRT is an array of straw tubes which integrate tracking and electron identification by transition radiation into one device. Results of experimental measurements and of comparisons with Monte Carlo simulations are presented for the electron identification performance as a function of various detector parameters. Under optimal operating conditions, a rejection against pions of a factor 100 was achieved with 90\% electron efficiency

Continuous immobilized yeast reactor system for complete beer fermentation using spent grains and corncobs as carrier materials

Despite extensive research carried out in the last few decades, continuous beer fermentation has not yet managed to outperform the traditional batch technology. An industrial breakthrough in favour of continuous brewing using immobilized yeast could be expected only on achievement of the following process characteristics: simple design, low investment costs, flexible operation, effective process control and good product quality. The application of cheap carrier materials of by-product origin could significantly lower the investment costs of continuous fermentation systems. This work deals with a complete continuous beer fermentation system consisting of a main fermentation reactor (gas-lift) and a maturation reactor (packedbed) containing yeast immobilized on spent grains and corncobs, respectively. The suitability of cheap carrier materials for long-term continuous brewing was proved. It was found that by fine tuning of process parameters (residence time, aeration) it was possible to adjust the flavour profile of the final product. Consumers considered the continuously fermented beer to be of a regular quality. Analytical and sensorial profiles of both continuously and batch fermented beers were compared.(Fundação de Amparo a Pesquisa do Estado de São Paulo, Brazil (FAPESPFundação para a Ciência e a Tecnologia (FC

Particle identification performance of a straw transition radiation tracker prototype

A 864 channel prototype of an integrated straw tracker and transition radiation detector for tracking and electron identification has been tested with and without magnetic field at the CERN SPS. The rejection against hadrons and converted photons has been measured and the dependence of the rejection power on detector parameters has been investigated. Tracking and hadron rejection were also studied in a high multiplicity environment. The results are compared with Monte-Carlo simulations. Wherever possible, conclusions are drawn concerning the performance of a full-scale detector at the future Large Hadron Collider