U.S.-Japan Cooperative Science: Spin Fluid Flow Dynamics in Polarized Superfluid

Award Number: 234032

Program(s): EAST ASIA AND PACIFIC PROGRAM

Start Date: 4/15/2003

Principal Investigator: Kojima, Haruo

Co-PI Name(s):

PI Email Address: kojima@physics.rutgers.edu

Abstract: 0234032

Kojima

This award supports a three-year collaborative research project between Professor Haruo Kojima at Rutgers University in New Brunswick and Professor Hidehiko Ishimoto at the Institute of Solid State Physics (ISSP) of the University of Tokyo in Japan. They will be undertaking research on spin fluid flow dynamics in polarized superfluid. A novel mechanical spin density detector technique has been developed for probing the nature of spin transport and relaxation effects. The technique will be applied to study the unusual spin transport and diffusion across two material states with different magnetic properties of their model system. Earlier experiments and analysis indicated that the presence of "interface" between the magnetic superfluid and either another superfluid or normal fluid exhibits very different mechanisms of spin relaxation. It is proposed to provide a direct test on the importance of the interface by measuring the spin relaxation in an arrangement which eliminates the interface altogether. The new spin filter experiment will increase spin polarization to much greater degree than possible in the past. A fluid state with large non-equilibrium polarization will be created and its dynamics will be studied.

The project brings together the efforts of two laboratories that have complementary expertise and research capabilities. The U.S. researchers provide expertise in the spin fluid flow dynamics experiments and the Japanese researchers provide expertise in ultra low temperature with a high magnetic field. Studies on spin dependent transport are important in advancing towards spintronics devices. The studies also have advantages in simpler structures because of the ease of changing material conditions and longer time scale involved. This would also contribute towards a better understanding of spintronics. The project advances international human resources through the participation of a number of graduate students who will gain experience in the state of art technology in ultra low temperature physics and materials physics. Through the exchange of ideas and technology, this project will broaden our base of basic knowledge and promote international understanding and cooperation. Results of the research will be disseminated at scientific meetings and in scientific journals.

U.S.-Japan Cooperative Science: Spin Fluid Flow Dynamics in Polarized Superfluid

Award Number: 234032

Program(s): EAST ASIA AND PACIFIC PROGRAM

Start Date: 4/15/2003

Principal Investigator: Kojima, Haruo

Co-PI Name(s):

PI Email Address: kojima@physics.rutgers.edu

Abstract: 0234032

Kojima

This award supports a three-year collaborative research project between Professor Haruo Kojima at Rutgers University in New Brunswick and Professor Hidehiko Ishimoto at the Institute of Solid State Physics (ISSP) of the University of Tokyo in Japan. They will be undertaking research on spin fluid flow dynamics in polarized superfluid. A novel mechanical spin density detector technique has been developed for probing the nature of spin transport and relaxation effects. The technique will be applied to study the unusual spin transport and diffusion across two material states with different magnetic properties of their model system. Earlier experiments and analysis indicated that the presence of "interface" between the magnetic superfluid and either another superfluid or normal fluid exhibits very different mechanisms of spin relaxation. It is proposed to provide a direct test on the importance of the interface by measuring the spin relaxation in an arrangement which eliminates the interface altogether. The new spin filter experiment will increase spin polarization to much greater degree than possible in the past. A fluid state with large non-equilibrium polarization will be created and its dynamics will be studied.

The project brings together the efforts of two laboratories that have complementary expertise and research capabilities. The U.S. researchers provide expertise in the spin fluid flow dynamics experiments and the Japanese researchers provide expertise in ultra low temperature with a high magnetic field. Studies on spin dependent transport are important in advancing towards spintronics devices. The studies also have advantages in simpler structures because of the ease of changing material conditions and longer time scale involved. This would also contribute towards a better understanding of spintronics. The project advances international human resources through the participation of a number of graduate students who will gain experience in the state of art technology in ultra low temperature physics and materials physics. Through the exchange of ideas and technology, this project will broaden our base of basic knowledge and promote international understanding and cooperation. Results of the research will be disseminated at scientific meetings and in scientific journals.

CAREER: Molecular Systems Bioengineering

Award Number: 238617

Program(s): BIOTECHNOLOGY

Start Date: 4/1/2003

Principal Investigator: Roth, Charles

Co-PI Name(s):

PI Email Address: cmroth@rci.rutgers.edu

Abstract: The overall objective of the proposed research is to develop tools of Molecular Systems Bioengineering (MSB) and apply them to understand and control gene regulatory events involved in hepatocyte (primary liver cell) differentiation. In the first stage of the project, individual binding sites on the albumin gene promoter will be assessed for liver-enriched transcription factor binding affinity and their ability to effect transcription of the albumin gene. In particular, context-dependent effects such as cooperativity and competition among binding sites will be evaluated quantitatively. Second, a molecular systems model will be developed to describe the gene network of regulatory interactions among liver-enriched transcription factor genes and corresponding proteins. Information on cooperativity and competition will be obtained from the experiments in the first stage, and the effect of genetic perturbations will be simulated. In the third stage, perturbations predicted to be fruitful will be effected using antisense oligonucleotides. Genes predicted to be most inhibitory to albumin transcription will be inhibited and the effects evaluated at the level of the gene target, albumin production and complementary hepatocyte differentiated functions. Concurrently, initiatives will be undertaken to create an educational path in Molecular Systems Bioengineering at Rutgers University. An undergraduate track in MSB will be developed in the Department of Biomedical Engineering, and interactive tutorials will be developed in the undergraduate core classes, which will be refined for use as translational materials in introducing high school student and Rutgers freshmen to opportunities in MSB.

New Developments in Longitudinal and Heterogeneous Data Analysis with Applications to the Social and Behavioral Sciences

Award Number: 241859

Program(s): METHOD, MEASURE and STATS, STATISTICS

Start Date: 4/1/2003

Principal Investigator: Xie, Minge

Co-PI Name(s):

PI Email Address: mxie@stat.rutgers.edu

Abstract: This research will develop new statistical methodologies and models for the analysis of categorical response data that occur frequently in the social and behavioral sciences. The main objective is to address some statistical issues that are related to the analysis of complex longitudinal and heterogeneous data when standard models such as the generalized linear models are inadequate. The research will explore several distinct modeling issues including, among others, parametric transformations of independent variables (covariates), the development of growth curve models for large-scale longitudinal social study data, and adapting heteroscedasticity in generalized linear models with non-parametrically scaled link functions. New methods and algorithms in estimations and inferences will be developed, including: 1) developing a general computing method for estimating transformation and regression parameters in covariate transformation models; 2) providing a stochastic-approximation-based computing algorithm for general mixed-effects models; and 3) developing efficient estimating equations for models with non-parametrically scaled link functions. The research also will develop large-sample-based supporting theories for the proposed methodologies. The research topics originally stemmed from some specific consulting projects in the social and behavioral sciences, but the methodologies to be developed are very general, with potential applications to many complex data analysis problems.

Molecular, Cluster, and Solid State Lanthanide Compounds With Electropositive Ligands

Award Number: 303075

Program(s): PHYSICAL INORGANIC

Start Date: 4/1/2003

Principal Investigator: Brennan, John

Co-PI Name(s):

PI Email Address: bren@rutchem.rutgers.edu

Abstract: This award by the Inorganic, Bioinorganic and Organometallic Chemistry program supports research by Dr. John G. Brennan, Department of Chemistry, Rutgers University to undertake a comprehensive investigation into the synthesis and characterization of lanthanide (Ln) molecules, clusters, and solid-state materials with direct bonds to the more electropositive chalcogens ( E = S, Se, Te). Relationships between the physical properties of molecules, clusters, and solids will be determined, with an emphasis placed on understanding how properties evolve as a function of system dimensionality. Synthetic methods leading to facile interconversion of molecular, cluster, and solid-state materials will be developed. These compounds are of interest as chemical reagents because the Ln-Te(R) bond is so readily disrupted. A second area to be developed is the synthesis of Ln compounds with particularly useful selenium-containing leaving groups, which also impart toluene solubility that is useful in cluster chemistry. Finally, volatile Ln compounds with selenium ligands are also targeted. These studies are designed to provide an understanding of how the chemical and physical properties of Ln compounds evolve as a function of particle size.

This multidisciplinary project will provide undergraduate and graduate students with a broad exposure to materials synthesis and characterization techniques and requires students to consider both practical and intellectual contributions to experimental design. This research impacts on organic chemistry by providing a totally new class of potential Lewis acid catalysts, reducing agents, or polymerization initiators. The proposed compounds are also useful sources for doping Ln ions into chalcogenido semiconductors or glasses, which have important implications in the manufacture of flat panel displays and optical fibers. The chemistry can also be developed as a low temperature (and thus low cost) approach to environmentally acceptable red-orange pigments that reduce the demand for Cd/Hg based materials.