Stevens Institute of Technology

About: Stevens Institute of Technology is a education organization based out in Hoboken, New Jersey, United States. It is known for research contribution in the topics: Cognitive radio & Wireless network. The organization has 5440 authors who have published 12684 publications receiving 296875 citations. The organization is also known as: Stevens & Stevens Tech.

Estimation of the parameters of Herschel-Bulkley fluid under wall slip using a combination of capillary and squeeze flow viscometers

Abstract: The determination of the parameters of viscoplastic fluids subject to wall slip is a special challenge and accurate results are generally obtained only when a number of viscometers are utilized concomitantly. Here the characterization of the parameters of the Herschel-Bulkley fluid and its non-linear wall slip behavior is formulated as an inverse problem which utilizes the data emanating from capillary and squeeze flow rheometers. A finite element method of the squeeze flow problem is employed in conjunction with the analytical solution of the capillary data collected following Mooney’s procedure, which uses dies with differing surface to volume ratios. The uniqueness of the solution is recognized as a major problem which limits the accuracy of the solution, suggesting that the search methodology should be carefully selected.

Engineering of Vascular Grafts With Genetically Modified Bone Marrow Mesenchymal Stem Cells on Poly (Propylene Carbonate) Graft

Abstract: Bone marrow mesenchymal stem cells (MSCs) have demonstrated their pluripotency to differentiate into different cell lineages and may be an alternative cell source for vascular tissue engineering. The objective of this study is to create small diameter vessels by seeding and culture of genetically modified MSCs onto a synthetic polymer scaffold produced by an electrospinning technique. A tubular scaffold (2 mm in diameter) with a microstructure of nonwoven fibers was produced by electrospinning of poly (propylene carbonate) (PPC). Rat MSCs obtained from bone marrow were expanded in culture and modified with vasculoprotective gene endothelial nitric oxide synthase (eNOS) or marker gene green fluorescent protein (GFP). These MSCs were seeded onto the electrospun fibrous grafts (internal diameter = 2 mm), and cultured in 5% CO(2) at 37 degrees C. The growth of MSCs in the scaffold was analyzed with scanning electron microscopy (SEM) and hematoxylin and eosin (H&E) staining. The gene transfer and transgenic gene expression were examined with fluorescence-activated cell sorting (FACS), immunochemical staining, reverse transcriptase-polymerase chain reaction (RT-PCR), and western blot. The production of nitric oxide (NO) by the engineered vessels was measured with an NO detection kit. Our data showed that the seeded cells integrated with the microfibers of the scaffold to form a three-dimensional cellular network, indicating a favorable interaction between this synthetic PPC scaffold with MSCs. High transduction efficiency was obtained with the use of concentrated retrovirus in the gene transfection of MSCs. The eNOS gene transcripts and protein were detected in the grafts seeded with eNOS-modified MSCs by RT-PCR and immunochemical staining. The amount of NO produced by grafts seeded with eNOS-modified MSCs was comparable to that produced by native blood vessels, and it was significantly higher than that in the grafts seeded with nonmodified MSCs. In summary, the vascular graft produced by culture of eNOS gene-modified MSCs onto the electrospun tubular scaffolds shows promising results in terms of function. The use of MSCs and therapeutic genes in tissue engineering of blood vessels could be helpful in improving vessel regeneration and patency.

Principles of Laser Spectroscopy and Quantum Optics

Abstract: Preface xv Chapter 1: Preliminaries 1 Chapter 2: Two-Level Quantum Systems 17 Chapter 3: Density Matrix for a Single Atom 56 Chapter 4: Applications of the Density Matrix Formalism 83 Chapter 5: Density Matrix Equations: Atomic Center-of-Mass Motion, Elementary Atom Optics, and Laser Cooling 99 Chapter 6: Maxwell-Bloch Equations 120 Chapter 7: Two-Level Atoms in Two or More Fields: Introduction to Saturation Spectroscopy 136 Chapter 8: Three-Level Atoms: Applications to Nonlinear Spectroscopy-Open Quantum Systems 159 Chapter 9: Three-Level Atoms: Dark States, Adiabatic Following, and Slow Light 184 Chapter 10: Coherent Transients 206 Chapter 11: Atom Optics and Atom Interferometry 242 Chapter 12: The Quantized, Free Radiation Field 280 Chapter 13: Coherence Properties of the Electric Field 312 Chapter 14: Photon Counting and Interferometry 339 Chapter 15: Atom-Quantized Field Interactions 358 Chapter 17: Optical Pumping and Optical Lattices 402 Chapter 18: Sub-Doppler Laser Cooling 422 Chapter 19: Operator Approach to Atom-Field Interactions: Source-Field Equation 453 Chapter 20: Light Scattering 474 Chapter 21: Entanglement and Spin Squeezing 492 References 506 Bibliography 507 Index 509