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Not All Traces On The Circle Come From Functions Of Least Gradient In The Disk, Gregory S. Spradlin, Alexandru Tamasan Jan 2014

Not All Traces On The Circle Come From Functions Of Least Gradient In The Disk, Gregory S. Spradlin, Alexandru Tamasan

Faculty Bibliography 2010s

We provide an example of an L-1 function on the unit circle that cannot be the trace of a function of bounded variation of least gradient in the unit disk.


Linear Quadratic Stochastic Differential Games- Open-Loop And Closed-Loop Saddle Points, Jingrui Sun, Jiongmin Yong Jan 2014

Linear Quadratic Stochastic Differential Games- Open-Loop And Closed-Loop Saddle Points, Jingrui Sun, Jiongmin Yong

Faculty Bibliography 2010s

In this paper, we consider a linear quadratic stochastic two-person zero-sum differential game. The controls for both players are allowed to appear in both drift and diffusion of the state equation. The weighting matrices in the performance functional are not assumed to be definite/nonsingular. The existence of an open-loop saddle point is characterized by the existence of an adapted solution to a linear forward-backward stochastic differential equation with constraints, together with a convexity-concavity condition, and the existence of a closed-loop saddle point is characterized by the existence of a regular solution to a Riccati differential equation. It turns out that …


Micro-Raman Spectroscopy Of Carbonaceous Chondrite Meteorites, Asmail Habach Jan 2014

Micro-Raman Spectroscopy Of Carbonaceous Chondrite Meteorites, Asmail Habach

HIM 1990-2015

Analyzing the constituents of meteorites has played an important role in forming the contemporary theories of solar system evolution, planets formation, and stellar evolution. Meteorites are often a complex mixture of common rock forming silicates, such as olivines and pyroxenes, with a range of exotic species including hydrated silicates, and in some cases organic compounds. We used Micro-Raman spectroscopy to analyze the compositions of three carbonaceous chondrites: NWA852, Murchison and Allende. Raman spectra were measured using laser sources with different excitation wavelengths: HeNe 633 nm and Nd:YAG 532 nm. We were able to detect 9 minerals in NWA852, 3 minerals …


The Effect Of Weight And Size On Mental Rotation, Luke Furtak Jan 2014

The Effect Of Weight And Size On Mental Rotation, Luke Furtak

HIM 1990-2015

Shepard and Metzler (1971) argued that mental rotation is analogous to the real world in that people imagine the rotation of an object as if it were being physically rotated. This study tested this assertion by exposing participants to physical shapes that increased in size and weight. Participants interacted with blocks designed after Shepard and Metzler mental rotation size that differed in size and weight then performed subsequent mental rotation. We found no difference in reaction time but found that increased size reduced accuracy. We discuss the implications of this study as they pertain to embodied cognition.


Pre-Service Teachers' Perceptions Of Promoting Teacher Autonomy Through The Use Of Lesson Study, Rachel Leon Jan 2014

Pre-Service Teachers' Perceptions Of Promoting Teacher Autonomy Through The Use Of Lesson Study, Rachel Leon

HIM 1990-2015

The intent of thesis is to explore pre-service teachers' perceptions of using a form of professional development to promote teacher autonomy. Current evidence shows that autonomy is a recurring element desired by American teachers in their profession. However, research advocates for teachers who are initiating and carrying out research in their schools (as a form of professional development) to have the potential to promote autonomy. For American teachers to gain a sense of autonomy in their profession there needs to be a change in the way professional development is directed. One form of professional development that promotes teachers as researchers …


Dissipative Solitons Of Self-Induced Transparency, G. T. Adamashvili, D. J. Kaup, A. Knorr Jan 2014

Dissipative Solitons Of Self-Induced Transparency, G. T. Adamashvili, D. J. Kaup, A. Knorr

Faculty Bibliography 2010s

A theory of dispersive soliton of the self-induced transparency in a medium consisting of atoms or semiconductor quantum dots of two types is considered. A two-component medium is modeled by a set of two-level atoms of two types embedded into a conductive host material. These types of atoms correspond to passive atoms (attenuator atoms) and active atoms (amplifier atoms) with inverse population of the energetic levels. The complete solution is given of the Maxwell-Bloch equations for ensembles of two-type atoms with different parameters and different initial conditions by inverse scattering transform. The solutions of the Maxwell-Bloch equations for many-component atomic …


Spectral Analysis Of The Truncated Hilbert Transform With Overlap, Reema Al-Aifari, Alexander Katsevich Jan 2014

Spectral Analysis Of The Truncated Hilbert Transform With Overlap, Reema Al-Aifari, Alexander Katsevich

Faculty Bibliography 2010s

We study a restriction of the Hilbert transform as an operator H-T from L-2(a(2), a(4)) to L-2(a(1), a(3)) for real numbers a(1) < a(2) < a(3) < a(4). The operator H-T arises in tomographic reconstruction from limited data, more precisely in the method of differentiated back-projection. There, the reconstruction requires recovering a family of one-dimensional functions f supported on compact intervals [a(2), a(4)] from its Hilbert transform measured on intervals [a(1), a(3)] that migH(T) only overlap, but not cover [a(2), a(4)]. We show that the inversion of H-T is ill-posed, which is why we investigate the spectral properties of H-T. We relate the operator H-T to a self-adjoint two-interval Sturm-Liouville problem, for which we prove that the spectrum is discrete. The Sturm-Liouville operator is found to commute with H-T, which then implies that the spectrum of (HTHT)-H-* is discrete. Furthermore, we express the singular value decomposition of H-T in terms of the solutions to the Sturm-Liouville problem. The singular values of H-T accumulate at both 0 and 1, implying that H-T is not a compact operator. We conclude by illustrating the properties obtained for H-T numerically.


A Non-Mle Approach For Satellite Scatterometer Wind Vector Retrievals In Tropical Cyclones, Suleiman Alsweiss, Rafik Hanna, Peth Laupattarakasem, W. Linwood Jones, Christopher C. Hennon, Ruiyao Chen Jan 2014

A Non-Mle Approach For Satellite Scatterometer Wind Vector Retrievals In Tropical Cyclones, Suleiman Alsweiss, Rafik Hanna, Peth Laupattarakasem, W. Linwood Jones, Christopher C. Hennon, Ruiyao Chen

Faculty Bibliography 2010s

Satellite microwave scatterometers are the principal source of global synoptic-scale ocean vector wind (OVW) measurements for a number of scientific and operational oceanic wind applications. However, for extreme wind events such as tropical cyclones, their performance is significantly degraded. This paper presents a novel OVW retrieval algorithm for tropical cyclones which improves the accuracy of scatterometer based ocean surface winds when compared to low-flying aircraft with in-situ and remotely sensed observations. Unlike the traditional maximum likelihood estimation (MLE) wind vector retrieval technique, this new approach sequentially estimates scalar wind directions and wind speeds. A detailed description of the algorithm is …


A One-Parameter Budyko Model For Water Balance Captures Emergent Behavior In Darwinian Hydrologic Models, Dingbao Wang, Yin Tang Jan 2014

A One-Parameter Budyko Model For Water Balance Captures Emergent Behavior In Darwinian Hydrologic Models, Dingbao Wang, Yin Tang

Faculty Bibliography 2010s

Hydrologic models can be categorized as being either Newtonian or Darwinian in nature. The Newtonian approach requires a thorough understanding of the individual physical processes acting in a watershed in order to build a detailed hydrologic model based on the conservation equations. The Darwinian approach seeks to explain the behavior of a hydrologic system as a whole by identifying simple and robust temporal or spatial patterns that capture the relevant processes. Darwinian-based hydrologic models include the Soil Conservation Service (SCS) curve number model, the "abcd" model, and the Budyko-type models. However, these models were developed based on widely differing principles …


The Postoperative Morbidity Index: A Quantitative Weighing Of Postoperative Complications Applied To Urological Procedures, Jonathan Beilan, Ruth Strakosha, Diego Aguilar Palacios, Charles J. Rosser Jan 2014

The Postoperative Morbidity Index: A Quantitative Weighing Of Postoperative Complications Applied To Urological Procedures, Jonathan Beilan, Ruth Strakosha, Diego Aguilar Palacios, Charles J. Rosser

Faculty Bibliography 2010s

Background: The reporting of post-operative complications in the urological field is lacking of a uniform quantitative measure to assess severity, which is essential in the analysis of surgical outcomes. The purpose of this study was to evaluate the feasibility of estimating quantitative severity weighing of post-operative complications after common urologic procedures. Methods: Using a large healthcare system's quality database, complications were identified in eleven common urologic procedures (e.g., insertion or replacement of inflatable penile prosthesis, nephroureterectomy, partial nephrectomy, percutaneous nephrostomy tube placement, radical cystectomy, radical prostatectomy, renal/ureteral/bladder extracorporeal shockwave lithotripsy (ESWL), transurethral destruction of bladder lesion, transurethral prostatectomy, transurethral removal …


An Efficient Collocation Method For A Class Of Boundary Value Problems Arising In Mathematical Physics And Geometry, A. H. Bhrawy, A. S. Alofi, R. A. Van Gorder Jan 2014

An Efficient Collocation Method For A Class Of Boundary Value Problems Arising In Mathematical Physics And Geometry, A. H. Bhrawy, A. S. Alofi, R. A. Van Gorder

Faculty Bibliography 2010s

We present a numerical method for a class of boundary value problems on the unit interval which feature a type of powerlaw nonlinearity. In order to numerically solve this type of nonlinear boundary value problems, we construct a kind of spectral collocation method. The spatial approximation is based on shifted Jacobi polynomials J(n)((alpha,beta))(r) with alpha,beta epsilon (-1, infinity), r epsilon (0,1) and n the polynomial degree. The shifted Jacobi-Gauss points are used as collocation nodes for the spectral method. After deriving the method for a rather general class of equations, we apply it to several specific examples. One natural example …


Numerical Investigation Of Stability Of Breather-Type Solutions Of The Nonlinear Schrodinger Equation, A. Calini, C. M. Schober Jan 2014

Numerical Investigation Of Stability Of Breather-Type Solutions Of The Nonlinear Schrodinger Equation, A. Calini, C. M. Schober

Faculty Bibliography 2010s

In this article we conduct a broad numerical investigation of stability of breather-type solutions of the nonlinear Schrodinger (NLS) equation, a widely used model of rogue wave generation and dynamics in deep water. NLS breathers rising over an unstable background state are frequently used to model rogue waves. However, the issue of whether these solutions are robust with respect to the kind of random perturbations occurring in physical settings and laboratory experiments has just recently begun to be addressed. Numerical experiments for spatially periodic breathers with one or two modes involving large ensembles of perturbed initial data for six typical …


Jacobi Rational-Gauss Collocation Method For Lane-Emden Equations Of Astrophysical Significance, Eid H. Doha, Ali H. Bhrawy, Ramy M. Hafez, Robert A. Van Gorder Jan 2014

Jacobi Rational-Gauss Collocation Method For Lane-Emden Equations Of Astrophysical Significance, Eid H. Doha, Ali H. Bhrawy, Ramy M. Hafez, Robert A. Van Gorder

Faculty Bibliography 2010s

In this paper, a new spectral collocation method is applied to solve Lane-Emden equations on a semi-infinite domain. The method allows us to overcome difficulty in both the nonlinearity and the singularity inherent in such problems. This Jacobi rational-Gauss method, based on Jacobi rational functions and Gauss quadrature integration, is implemented for the nonlinear Lane-Emden equation. Once we have developed the method, numerical results are provided to demonstrate the method. Physically interesting examples include Lane-Emden equations of both first and second kind. In the examples given, by selecting relatively few Jacobi rational-Gauss collocation points, we are able to get very …


Exceptional Points And Lasing Self-Termination In Photonic Molecules, R. El-Ganainy, M. Khajavikhan, Li Ge Jan 2014

Exceptional Points And Lasing Self-Termination In Photonic Molecules, R. El-Ganainy, M. Khajavikhan, Li Ge

Faculty Bibliography 2010s

We investigate the rich physics of photonic molecule lasers using a non-Hermitian dimer model. We show that several interesting features, predicted recently using a rigorous steady-state ab initio laser theory (SALT), can be captured by this toy model. In particular, we demonstrate the central role played by exceptional points (EPs) in both pump-selective lasing and laser self-termination phenomena. Due to its transparent mathematical structure, our model provides a lucid understanding for how different physical parameters (optical loss, modal coupling between microcavities, and pump profiles) affect the lasing action. Interestingly, our analysis also confirms that, for frequency mismatched cavities, operation in …


High-Performance Near-Infrared Imaging For Breast Cancer Detection, Yasser H. El-Sharkway, Ashraf F. El-Sherif Jan 2014

High-Performance Near-Infrared Imaging For Breast Cancer Detection, Yasser H. El-Sharkway, Ashraf F. El-Sherif

Faculty Bibliography 2010s

We present a method for the noninvasive determination of the size, position, and optical properties of tumors in the human breast. The tumor is first detected by photothermal imaging. It is then sized, located, and optically characterized using designed digital image processing and edge-detection pattern recognition. The method assumes that the tumor is spherical and inhomogeneous and embedded in an otherwise homogeneous tissue. Heat energy is deposited in the tissue by absorption of near-infrared (NIR) Nd:YAG laser radiation, and its subsequent conversion to heat via vibrational relaxation causes a rise in temperature of the tissue. The tumor absorbs and scatters …


Probealign: Incorporating High-Throughput Sequencing-Based Structure Probing Information Into Ncrna Homology Search, Ping Ge, Cuncong Zhong, Shaojie Zhang Jan 2014

Probealign: Incorporating High-Throughput Sequencing-Based Structure Probing Information Into Ncrna Homology Search, Ping Ge, Cuncong Zhong, Shaojie Zhang

Faculty Bibliography 2010s

Background: Recent advances in RNA structure probing technologies, including the ones based on high-throughput sequencing, have improved the accuracy of thermodynamic folding with quantitative nucleotide-resolution structural information. Results: In this paper, we present a novel approach, ProbeAlign, to incorporate the reactivities from high-throughput RNA structure probing into ncRNA homology search for functional annotation. To reduce the overhead of structure alignment on large-scale data, the specific pairing patterns in the query sequences are ignored. On the other hand, the partial structural information of the target sequences embedded in probing data is retrieved to guide the alignment. Thus the structure alignment problem …


Intravitreal Aflibercept Outcomes In Patients With Persistent Macular Exudate Previously Treated With Bevacizumab And/Or Ranibizumab For Neovascular Age-Related Macular Degeneration, David R. Griffin, Preston P. Richmond, John C. Olson Jan 2014

Intravitreal Aflibercept Outcomes In Patients With Persistent Macular Exudate Previously Treated With Bevacizumab And/Or Ranibizumab For Neovascular Age-Related Macular Degeneration, David R. Griffin, Preston P. Richmond, John C. Olson

Faculty Bibliography 2010s

Purpose. To assess whether intravitreal aflibercept (2.0mg) can effectively reduce persistent macular exudate and enhance visual acuity in ranibizumab (0.5mg) and/or bevacizumab (1.25 mg) treatment resistant patients with neovascular age-related macular degeneration. Methods. This retrospective study included 47 treatment resistant eyes from 47 patients switched to intravitreal aflibercept injections after receiving a minimum of 3 injections with either ranibizumab or bevacizumab. Snellen visual acuity and optical coherence tomography were assessed just prior to the first injection (baseline) and prior to the fourth injection (final). Additionally, anatomical regions of persistent macular exudate were tracked to determine if these areas yielded varying …


Supersymmetric Mode Converters, Matthias Heinrich, Mohammad-Ali Miri, Simon Stützer, Ramy El-Ganainy, Stefan Nolte, Alexander Szameit, Demetrios N. Christodoulides Jan 2014

Supersymmetric Mode Converters, Matthias Heinrich, Mohammad-Ali Miri, Simon Stützer, Ramy El-Ganainy, Stefan Nolte, Alexander Szameit, Demetrios N. Christodoulides

Faculty Bibliography 2010s

Originally developed in the context of quantum field theory, the concept of supersymmetry can be used to systematically design a new class of optical structures. In this work, we demonstrate how key features arising from optical supersymmetry can be exploited to control the flow of light for mode-division multiplexing applications. Superpartner configurations are experimentally realized in coupled optical networks, and the corresponding light dynamics in such systems are directly observed. We show that supersymmetry can be judiciously used to remove the fundamental mode of a multimode optical structure while establishing global phase-matching conditions for the remaining set of modes. Along …


Beta-Alanine Supplementation Improves Tactical Performance But Not Cognitive Function In Combat Soldiers, Jay R. Hoffman, Geva Landau, Jeffrey R. Stout, Matan Dabora, Daniel S. Moran, Nurit Sharvit, Mattan W. Hoffman, Yuval Ben Moshe, William P. Mccormack, Gil Hirschhorn, Ishay Ostfeld Jan 2014

Beta-Alanine Supplementation Improves Tactical Performance But Not Cognitive Function In Combat Soldiers, Jay R. Hoffman, Geva Landau, Jeffrey R. Stout, Matan Dabora, Daniel S. Moran, Nurit Sharvit, Mattan W. Hoffman, Yuval Ben Moshe, William P. Mccormack, Gil Hirschhorn, Ishay Ostfeld

Faculty Bibliography 2010s

Background: There are no known studies that have examined beta-alanine supplementation in military personnel. Considering the physiological and potential neurological effects that have been reported during sustained military operations, it appears that beta-alanine supplementation may have a potential benefit in maintaining physical and cognitive performance during high-intensity military activity under stressful conditions. The purpose of this study was to examine the effect of 28 days of beta-alanine ingestion in military personnel while fatigued on physical and cognitive performance. Methods: Twenty soldiers (20.1 +/- 0.9 years) from an elite combat unit were randomly assigned to either a beta-alanine ( BA) or …


Exact And Approximate Solutions For Nonlinear Pdes, Baojian Hong, Dianchen Lu, Chaudry Masood Khalique, Alvaro H. Salas, Robert A. Van Gorder Jan 2014

Exact And Approximate Solutions For Nonlinear Pdes, Baojian Hong, Dianchen Lu, Chaudry Masood Khalique, Alvaro H. Salas, Robert A. Van Gorder

Faculty Bibliography 2010s

No abstract provided.


Mediators Of Monocyte Migration In Response To Recovery Modalities Following Resistance Exercise, Adam R. Jajtner, Maren S. Fragala, Jeremy R. Townsend, Adam M. Gonzalez, Adam J. Wells, David H. Fukuda, Jeffrey R. Stout, Jay R. Hoffman Jan 2014

Mediators Of Monocyte Migration In Response To Recovery Modalities Following Resistance Exercise, Adam R. Jajtner, Maren S. Fragala, Jeremy R. Townsend, Adam M. Gonzalez, Adam J. Wells, David H. Fukuda, Jeffrey R. Stout, Jay R. Hoffman

Faculty Bibliography 2010s

Mediators of monocyte migration, complement receptor-3 (CR3), and chemokine ligand-4 (CCL4) were measured in response to recovery modalities following resistance exercise. Thirty resistance-trained men (23.1 +/- 2.9 y; 175.2 +/- 7.1 cm; 82.1 +/- 8.4 kg) were given neuromuscular electric stimulation (NMES), cold water immersion (CWI), or control (CON) treatments immediately following resistance exercise. Blood samples were obtained preexercise (PRE), immediately (IP), 30 minutes (30 P), 24 hours (24 H), and 48 hours (48 H) after exercise for measurement of circulating CCL4 and CR3 expression on CD14+ monocytes, by assay and flow cytometry. Circulating CCL4 showed no consistent changes. Inferential …


The Heisenberg Relation - Mathematical Formulations, Richard V. Kadison, Zhe Liu Jan 2014

The Heisenberg Relation - Mathematical Formulations, Richard V. Kadison, Zhe Liu

Faculty Bibliography 2010s

We study some of the possibilities for formulating the Heisenberg relation of quantum mechanics in mathematical terms. In particular, we examine the framework discussed by Murray and von Neumann, the family (algebra) of operators affiliated with a finite factor (of infinite linear dimension).


A Note On Derivations Of Murray-Von Neumann Algebras, Richard V. Kadison, Zhe Liu Jan 2014

A Note On Derivations Of Murray-Von Neumann Algebras, Richard V. Kadison, Zhe Liu

Faculty Bibliography 2010s

A Murray-von Neumann algebra is the algebra of operators affiliated with a finite von Neumann algebra. In this article, we first present a brief introduction to the theory of derivations of operator algebras from both the physical and mathematical points of view. We then describe our recent work on derivations of Murray-von Neumann algebras. We show that the "extended derivations" of a Murray-von Neumann algebra, those that map the associated finite von Neumann algebra into itself, are inner. In particular, we prove that the only derivation that maps a Murray-von Neumann algebra associated with a factor of type II1 into …


Stretching And Compressing Of Short Laser Pulses By Chirped Volume Bragg Gratings: Analytic And Numerical Modeling, Sergiy Kaim, Sergiy Mokhov, Boris Y. Zeldovich, Leonid B. Glebov Jan 2014

Stretching And Compressing Of Short Laser Pulses By Chirped Volume Bragg Gratings: Analytic And Numerical Modeling, Sergiy Kaim, Sergiy Mokhov, Boris Y. Zeldovich, Leonid B. Glebov

Faculty Bibliography 2010s

The theory of stretching and compression of short light pulses by chirped volume Bragg gratings (CBGs) is reviewed based on spectral decomposition of short pulses and on wavelength-dependent coupled wave equations. Analytic theory of diffraction efficiency of CBG with constant chirp and approximate theory time-delay dispersion is presented. Comparison of approximate analytic results with exact numeric coupled-wave modeling shows excellent agreement for smooth heterogeneities of CBGs. (C) The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its …


Determination Of Critical Rest Interval Using Repeated Sprint Ability Testing, Michael La Monica Jan 2014

Determination Of Critical Rest Interval Using Repeated Sprint Ability Testing, Michael La Monica

Electronic Theses and Dissertations

The critical power (CP) concept has been used to determine the appropriate rest interval during intermittent exercise through the investigation of critical rest interval (CRI). Repeated sprint ability (RSA) testing has been developed to define the athlete’s ability to recover and maintain maximal effort during successive bouts. The CP model has been used to understand the physiological responses involved with intermittent exercise delineating between severe and heavy exercise intensity domains. The primary purpose of this study was to determine the CRI from the work-time relationship given by RSA testing using varying work to rest ratios. The secondary purpose was to …


Bio-Inspired Attitude Control Of Micro Air Vehicles Using Rich Information From Airflow Sensors, He Shen Jan 2014

Bio-Inspired Attitude Control Of Micro Air Vehicles Using Rich Information From Airflow Sensors, He Shen

Electronic Theses and Dissertations

Biological phenomena found in nature can be learned and customized to obtain innovative engineering solutions. In recent years, biologists found that birds and bats use their mechanoreceptors to sense the airflow information and use this information directly to achieve their agile flight performance. Inspired by this phenomenon, an attitude control system for micro air vehicles using rich amount of airflow sensor information is proposed, designed and tested. The dissertation discusses our research findings on this topic. First, we quantified the errors between the calculated and measured lift and moment profiles using a limited number of micro pressure sensors over a …


Self-Heating Control Of Edge Emitting And Vertical Cavity Surface Emitting Lasers, Yu Zhang Jan 2014

Self-Heating Control Of Edge Emitting And Vertical Cavity Surface Emitting Lasers, Yu Zhang

Electronic Theses and Dissertations

Self-heating leads to temperature rise of laser diode and limits the output power, efficiency and modulation bandwidth due to increased loss and decreased differential gain. The main heat sources in laser diode during continuous wave operation are Joule heating and free carrier absorption loss. To control device self-heating, the epi structure needs to be designed with low electrical resistance and low absorption loss, while the heat flux must spread out of the device efficiently. This dissertation presents the control of self-heating of both edge emitting laser diodes and vertical cavity surface emitting lasers (VCSELs). For the 980nm high power edge …


Particle Manipulation Via Optical Forces And Engineering Soft-Matter Systems With Tunable Nonlinearities., Shima Fardad Jan 2014

Particle Manipulation Via Optical Forces And Engineering Soft-Matter Systems With Tunable Nonlinearities., Shima Fardad

Electronic Theses and Dissertations

One of the most intriguing properties of light-matter interaction is the ability of an electromagnetic field to exert mechanical forces on polarizable objects. This phenomenon is a direct consequence of the fact that light carries momentum, which in turn can be transferred to matter. Mediated by scattering, this interaction usually manifests itself as a “pushing force” in the direction of beam propagation. However, it is possible to judiciously engineer these optical forces, either by tailoring particle polarizability, and/or by structuring the incident light field. As a simple example, a tightly focused laser beam demonstrates strong gradient forces, which may attract …


Frequency Selective Detection Of Infrared Radiation In Uncooled Optical Nano-Antenna Array, Sushrut Modak Jan 2014

Frequency Selective Detection Of Infrared Radiation In Uncooled Optical Nano-Antenna Array, Sushrut Modak

Electronic Theses and Dissertations

Mid-infrared (mid-IR) detection and imaging over atmospheric transparent 3-5 μm and 8-12 μm bands are increasingly becoming important for various space, defense and civilian applications. Various kinds of microbolometers offer uncooled detection of IR radiation. However, broadband absorption of microbolometers makes them less sensitive to spectrally resolved detection of infrared radiation and the fabrication is also very tedious involving multiple complex lithography steps. In this study, we designed an optical nano-antenna array based detector with narrow frequency band of operation. The structure consists of a two-element antenna array comprised of a perforated metallic hole array coupled with an underneath disk …


Fluorescence Off-On Sensors For F-, K+, Fe3+, And Ca2+ Ions, Binglin Sui Jan 2014

Fluorescence Off-On Sensors For F-, K+, Fe3+, And Ca2+ Ions, Binglin Sui

Electronic Theses and Dissertations

Fluorescence spectroscopy has been considered to be one of the most important research techniques in modern analytical chemistry, biochemistry, and biophysics. At present, fluorescence is a dominant methodology widely used in a great number of research domains, including biotechnology, medical diagnostics, genetic analysis, DNA sequencing, flow cytometry, and forensic analysis, to name just a few. In the past decade, with the rapid development of fluorescence microscopy, there has been a considerable growth in applying fluorescence technique to cellular imaging. The distinguished merits of fluorescence techniques, such as high sensitivity, non-invasiveness, low cytotoxicity, low cost, and convenience, make it a promising …