GE Global Research Center Research Articles

Clearance of Gadolinium from the Brain with No Pathologic Effect after Repeated Administration of Gadodiamide in Healthy Rats: An Analytical and Histologic Study.

Purpose To measure the levels of gadolinium present in the rat brain 1 and 20 weeks after dosing with contrast agent and to determine if there are any histopathologic sequelae. Materials and Methods The study was approved by the GE Global Research Center Institutional Animal Care and Use Committee. Absolute gadolinium levels were quantified in the blood and brains of rats 1 week after dosing and 20 weeks after dosing with up to 20 repeat doses of gadodiamide (cumulative dose, 12 mmol per kilogram of body weight) by using inductively coupled plasma-mass spectrometry. Treatment groups (n = 6 rats per group) included low-dosage and high-dosage gadodiamide and osmolality-matched saline controls. Brain sections were submitted (blinded) for standard toxicology assessment per Registry of Industrial Toxicology Animal data guidelines. Analysis of variance and Mann-Whitney U tests with post hoc correction were used to assess differences in absolute gadolinium levels and percentage of injected dose, respectively. Results Dose-dependent low levels of gadolinium were detected in the brain, a mean ± standard deviation of 2.49 nmol per gram of brain tissue ± 0.30 or 0.00019% of the injected dose 1 week after dosing. This diminished by approximately 50% (to 1.38 nmol per gram of brain tissue ± 0.10 or 0.00011% of the injected dose) 20 weeks after dosing. As a percentage of injected dose, the levels of gadolinium measured were comparable between different doses, indicating that mechanisms of uptake and elimination were not saturated at the tested doses. There were no histopathologic findings associated with the levels of gadolinium measured. Conclusion Low levels of gadolinium are present in the brain after repeat dosing with gadodiamide, which is partially cleared over 20 weeks with no detectable neurotoxicity.

Quantified pH detection with hyperpolarized 13C-Bicarbonate

Event Abstract Back to Event Quantified pH detection with hyperpolarized 13C-Bicarbonate Johannes Scholz1, 2*, Martin A. Janich2, Angela M. Otto1, Franz Schilling1, Axel Haase1 and Marion I. Menzel2 1 Technische Universität München, Physics, Germany 2 GE Global Research Center, Germany Background and aim. pH plays a crucial role in several diseases, such as cancer, hypoxia, inflammation etc., and it is therefore desirable to detect pH in vivo. Ideally, the detection should be noninvasive and spatially localized. Despite the medical impact, a clinical tool for pH mapping is not yet available. Different approaches in pH detection were made in NMR e.g. with 31P and CEST.[1] A promising candidate to achieve pH mapping in vivo is 13C metabolic magnetic resonance (13CMMR). This technique enhances the signal of 13C-labeled bicarbonate using dissolution dynamic nuclear polarization (DNP) and then probes the pH by measuring the ratio of 13C bicarbonate and 113CO2 [2]. Methods. Hyperpolarization is achieved using dissolution DNP Hypersense polarizer. The MR acquisition is performed on pH phantoms and mammary carcinoma cell spheroids (MCF-7) using a 3T MR system (GE Signa HDx) and a 14T Bruker spectrometer. Relaxation time analysis was additionally performed with a 1T Bruker Minispec mq40 NMR analyzer. Results. In vitro tests using hyperpolarized sodium bicarbonate and phosphate buffers and pH-phantoms showed good correlation between the derived pH value and the reference pH (+/- 0.03) obtained with a pH electrode. An analysis of the signal dynamics revealed that the correct bicarbonate to CO2 signal ratio is established after 40 seconds without adding carbonic anhydrases. In tumor cell systems (MCF-7 spheroids), T1 times of bicarbonate and CO2 were determined for different field strengths (1T, 3T, 14T) and different pH values in the biological range (6-8). Comparison of the values achieved with and without tumor spheroids show the impact of the spheroids on the hyperpolarized signal. Acknowledgements This research was partly funded by BMBF grant 01EZ1114A.

NAE Elects New Members In 2013

The National Academy of Engineering elected 69 members and 11 foreign associates last month. The academy now totals 2,250 U.S. members and 211 foreign associates. Individuals are elected to NAE on the basis of outstanding contributions to engineering research, practice, or education. Of the new members and foreign associates, 20 are scientists who work in chemistry-related areas or are members of the American Chemical Society. The chemistry-related new members are James M. Anderson, Case Western Reserve University, for researching interactions between tissue and biomaterials and developing medical devices; Peter L. Andresen, GE Global Research Center, for predicting and preventing stress corrosion cracking in nuclear materials; Lorenz T. Biegler, Car­ne­gie Mellon University, for contributing to large-scale nonlinear optimization theory and its application; Donna G. Blackmond, Scripps Research Institute, La Jolla, Calif., for studying catalytic organic reactions and chiral amplification; Dawn A. Bonnell, ...

Retiring Associate Editors

Retiring Associate Editors

Hierarchical spatiotemporal modeling for dynamic video trajectory analysis

Normalcy decision in video security involves highly uncertain phenomena due to its inherited insufficient knowledge, intrinsic ambiguity in human cognition, measurement error, etc. This paper presents a hierarchical spatiotemporal trajectory modeling for dynamic trajectory analysis using sparse trajectory data. The trajectory data is assumed to be given by people detection and tracking methods, which are also challenging issues due to occlusion, noise, illumination changes, etc. The proposed method partitions the trajectory feature space into the attributes of trajectory position, direction, and speed. Inherent uncertainty of video trajectory is tackled by employing the uncertainty propagation model of a trajectory segment and Markov random field in analyzing the uncertainty attributes of object movement direction and speed. The proposed method can be used in online learning for incremental adaptation as well as offline learning for optimality guarantee. The method was evaluated using both synthetic trajectories and video streams of multiple people movements acquired from multiple video cameras developed by GE Global Research Center and KAL beta sites. Extensive experiments were performed using video sequences in real world and synthesized trajectories, which achieved very encouraging results.

Understanding and controlling the effect of lossy raw data compression on CT images

The requirements for raw data transmission through a CT scanner slip ring, through the computation system, and for storage of raw CT data can be quite challenging as scanners continue to increase in speed and to collect more data per rotation. Although lossy compression greatly mitigates this problem, users must be cautious about how errors introduced manifest themselves in the reconstructed images. This paper describes two simple yet effective methods for controlling the effect of errors in raw data compression and describe the impact of each stage on the image errors. A CT system simulator (CATSIM, GE Global Research Center, Niskayuna, NY) was used to generate raw CT datasets that simulate different regions of human anatomy. The raw data are digitized by a 20-bit ADC and companded by a log compander. Lossy compression is performed by quantization and is followed by JPEG-LS (lossless), which takes advantage of the correlations between neighboring measurements in the sinogram. Error feedback, a previously proposed method that controls the spatial distribution of reconstructed image errors, and projection filtering, a newly proposed method that takes advantage of the filtered backprojection reconstruction process, are applied independently (and combined) to study their intended impact on the control and behavior of the additional noise due to the compression methods used. The log compander and the projection filtering method considerably reduce image error levels, while error feedback pushes image errors toward the periphery of the field of view. The results for the images are a compression ratio (CR) of 3 that keeps peak compression errors under 1 HU and a CR of 9 that increases image noise by only 1 HU in common CT applications. Lossy compression can substantially reduce raw CT data size at low computational cost. The proposed methods have the flexibility to operate at a wide range of compression ratios and produce predictable, object-independent, and often imperceptible image artifacts.

Researching for the future [manufacturing research

It may describe itself as a global infrastructure, finance and media company. but with interests from everyday light bulbs to fuel cell technology, and from carbon composites to cleaner, more efficient jet engines, General Electric Company (GE) knows that it can't succeed without also investing in research and development - including long- term research. The paper presents the efforts of GE's global research center which is committed not only for product lines' advanced technologies but also finding ways to alternative energy and environmental technologies.

Micro and Nano R&D Fab Performance and Productivity A Lean Six-Sigma Approach

A lean six-sigma approach was utilized to improve the performance of a multi-technology R&D cleanroom facility at GE's Global Research Center (GRC). The lean initiative prioritized 4 areas for improvement: 1) fab loading and lot priority, 2) documentation, 3) equipment and, 4) maintenance. A set of four metrics (throughput, uptime, process time, and lot queue time) for each piece of equipment was utilized to measure and drive cleanroom operational performance improvements. Subsequent activities relied on more sophisticated analysis of these metrics as a basis for prioritizing additional improvement tasks. Projects that improved the data management systems, and lot process documentation were also completed. After implementing the improvements that were uncovered from the lean six-sigma approach, lot cycle time improved more than 3x in the best cases, while a 50% average reduction in equipment queue time was achieved. The initiative resulted in a 16% increase in productivity while overall fab loading grew by 25%. The cleanroom achieved lower research and development costs while simultaneously increasing technology capacity, reducing lot cycle times, and maintaining process control.

Using Electronic Surveys in Organizational/Employee Communication Research: A Study at GE's Global Research Center

This study explores methodological issues that communication scholars and practitioners face when administering electronic surveys within for-profit organizations. In 2000, the researchers conducted a series of three cross-sectional studies within General Electric's (GE) Global Research Center. The Center is located in Niskayuna, NY. An equivalent version of a communication survey was administered electronically to a random stratified sample of GE employees three times that year. Each employee sample was subject to a different survey intervention: no intervention, follow-up reminder email only, and leader pre-announcement email plus a follow-up reminder. The researchers also recorded how long it took respondents to return their surveys. The highest response rate (41%) occurred in the third intervention. Across the three administrations, 465 GE employees completed the surveys; 98% of respondents returned their surveys electronically rather than printing out their responses and sending them to the researcher by postal mail. The article concludes with implications and suggestions for those who administer electronic surveys within organizations.

Quench Test of HTS Coils for Generator Application at GE

When a synchronous generator connected to the power grid experiences a fault, it is required to stay on line, ride through the fault, and be able to carry full rated field current when the fault is cleared. The peak current during these events could be 2 times higher than the normal operating current. This may cause an HTS rotor coil to go into normal state and generate Joule heating. If the fault event is short enough and the heat dumped can be carried away by the cooling system, the coil may recover to the superconducting state at the end of the fault. Otherwise, the coil may thermally run away, or dasiaquenchpsila. To investigate the quench behavior of the HTS rotor coil of the 100 MVA generator at GE Global Research Center, a 1.5 MVA prototype coil was developed and tested to quench under different conditions. The experiment design, set up, tests and test results are presented in this paper.

Development of a Large Bore Long Pulse Magnet at GE Global Research Center

A 3.5 Tesla pulsed magnet with a 1.35 meter bore wound with copper strips has been developed, successfully tested and used at GE Global Research. The magnet has energy of 14 MJ at the peak field. The magnet is composed of 4 pancake coils in series pre-cooled with liquid Nitrogen and powered by a 750 V, 8000 A power supply. This paper describes the design of the magnet, power supply, control circuit and the test results of the system

GE's Energy Rentals Business Automates Its Credit Assessment Process

GE Energy Rentals, a business unit of General Electric Power Systems (GEPS), uses an automated Web-based application to assess customers' credit worthiness. GE's Global Research Center developed the system using quantitative business modeling and decision-support-system design. The system uses a model for credit decisions that captures the thought process expert credit analysts use to assign credit lines to customers. In addition, the system provides users with the analytics and reasons underlying credit decisions. It has enhanced productivity and efficiency by speeding up credit approvals. In addition, by providing a standard platform for credit approvals, it ensures consistency in the process of assessing and approving credit. The system has decreased costs by eliminating a credit-analyst position despite growth in the business and has also saved over 60 percent of the costs per credit decision. We are adapting this approach for other GEPS business units.

D024 X-ray Diffraction and More at GE Global Research Center - Invited

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Combining Medical Informatics and Bioinformatics toward Tools for Personalized Medicine

Key bioinformatics and medical informatics research areas need to be identified to advance knowledge and understanding of disease risk factors and molecular disease pathology in the 21 st century toward new diagnoses, prognoses, and treatments. Three high-impact informatics areas are identified: predictive medicine (to identify significant correlations within clinical data using statistical and artificial intelligence methods), along with pathway informatics and cellular simulations (that combine biological knowledge with advanced informatics to elucidate molecular disease pathology). Initial predictive models have been developed for a pilot study in Huntington's disease. An initial bioinformatics platform has been developed for the reconstruction and analysis of pathways, and work has begun on pathway simulation. A bioinformatics research program has been established at GE Global Research Center as an important technology toward next generation medical diagnostics. We anticipate that 21 st century medical research will be a combination of informatics tools with traditional biology wet lab research, and that this will translate to increased use of informatics techniques in the clinic.