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A New Nonlinear Analytical Model For Canopy Flow Over A Forested Hill, Weiguo Wang, Chuixiang Yi Aug 2012

A New Nonlinear Analytical Model For Canopy Flow Over A Forested Hill, Weiguo Wang, Chuixiang Yi

Publications and Research

A new nonlinear analytical model for canopy flow over gentle hills is presented. This model is established based on the assumption that three major forces (pressure gradient, Reynolds stress gradient, and nonlinear canopy drag) within canopy are in balance for gentle hills under neutral conditions. The momentum governing equation is closed by the velocity-squared law. This new model has many advantages over the model developed by Finnigan and Belcher (2004, hereafter referred to as FB04) in predicting canopy wind velocity profiles in forested hills in that: (1) this model predictions are more realistic because the surface drag can be taken …


An Integrated Vendor-Buyer Cooperative Inventory Model For Items With Imperfect Quality And Shortage Backordering, Jia-Tzer Hsu, Lie-Fern Hsu Jul 2012

An Integrated Vendor-Buyer Cooperative Inventory Model For Items With Imperfect Quality And Shortage Backordering, Jia-Tzer Hsu, Lie-Fern Hsu

Publications and Research

We develop a model to determine an integrated vendor-buyer inventory policy for items with imperfect quality and planned back orders. The production process is imperfect and produces a certain number of defective items with a known probability density function. The vendor delivers the items to the buyer in small lots of equally sized shipments. Upon receipt of the items, the buyer will conduct a 100% inspection. Since each lot contains a variable number of defective items, shortages may occur at the buyer. We assume that shortages are permitted and are completely back ordered. The objective is to minimize the total …


Detecting The Immune System Response Of A 500 Year-Old Inca Mummy, Angelique Corthals, Antonius Koller, Dwight W. Martin, Robert Rieger, Emily I. Chen, Mario Bernaski, Gabriella Recagno, Liliana M. Dávalos Jul 2012

Detecting The Immune System Response Of A 500 Year-Old Inca Mummy, Angelique Corthals, Antonius Koller, Dwight W. Martin, Robert Rieger, Emily I. Chen, Mario Bernaski, Gabriella Recagno, Liliana M. Dávalos

Publications and Research

Disease detection in historical samples currently relies on DNA extraction and amplification, or immunoassays. These techniques only establish pathogen presence rather than active disease. We report the first use of shotgun proteomics to detect the protein expression profile of buccal swabs and cloth samples from two 500-year-old Andean mummies. The profile of one of the mummies is consistent with immune system response to severe pulmonary bacterial infection at the time of death. Presence of a probably pathogenic Mycobacterium sp. in one buccal swab was confirmed by DNA amplification, sequencing, and phylogenetic analyses. Our study provides positive evidence of active pathogenic …


Inhibition Of Pokeweed Antiviral Protein (Pap) By Turnip Mosaic Virus Genome-Linked Protein (Vpg), Artem V. Domashevskiy, Hiroshi Miyoshi, Dixie J. Goss Jul 2012

Inhibition Of Pokeweed Antiviral Protein (Pap) By Turnip Mosaic Virus Genome-Linked Protein (Vpg), Artem V. Domashevskiy, Hiroshi Miyoshi, Dixie J. Goss

Publications and Research

Pokeweed antiviral protein (PAP) from Phytolacca americana is a ribosome-inactivating protein (RIP) and an RNA N-glycosidase that removes specific purine residues from the sarcin/ricin loop of large rRNA, arresting protein synthesis at the translocation step. PAP is also a cap-binding protein and is a potent antiviral agent against many plant, animal, and human viruses. To elucidate the mechanism of RNA depurination, and to understand how PAP recognizes and targets various RNAs, the interactions between PAP and turnip mosaic virus genomelinked protein (VPg) were investigated. VPg can function as a cap analog in cap-independent translation and potentially target PAP to uncapped …


Potential Significance Of Photoexcited No2 On Global Air Quality With The Nmmb/Bsc Chemical Transport Model, O. Jorba, D. Dabdub, Christopher S. Blaszczak-Boxe, C. Pérez, Z. Janjic, J. M. Baldasano, M. Spada, A. Badia, M. Gonçalves Jul 2012

Potential Significance Of Photoexcited No2 On Global Air Quality With The Nmmb/Bsc Chemical Transport Model, O. Jorba, D. Dabdub, Christopher S. Blaszczak-Boxe, C. Pérez, Z. Janjic, J. M. Baldasano, M. Spada, A. Badia, M. Gonçalves

Publications and Research

Atmospheric chemists have recently focused on the relevance of the NO2* + H2O → OH + HONO reaction to local air quality. This chemistry has been considered not relevant for the troposphere from known reaction rates until nowadays. New experiments suggested a rate constant of 1.7 × 10−13 cm3 molecule−1 s−1, which is an order of magnitude faster than the previously estimated upper limit of 1.2 × 10−14 cm3 molecule−1 s−1, determined by Crowley and Carl (1997). Using the new global model, NMMB/BSC Chemical Transport Model (NMMB/BSC-CTM), simulations are presented that assess the potential significance of this chemistry on global …


Halogen Activation Via Interactions With Environmental Ice And Snow In The Polar Lower Troposphere And Other Regions, J. P. D. Abbatt, J. L. Thomas, K. Abrahamsson, Chris Boxe, A. Granfors, A. E. Jones, M. D. King, A. Saiz-Lopez, P. B. Shepson, J. Sodeau, D. W. Toohey, C. Toubin, R. Von Glasow, S. N. Wren, X. Yang Jul 2012

Halogen Activation Via Interactions With Environmental Ice And Snow In The Polar Lower Troposphere And Other Regions, J. P. D. Abbatt, J. L. Thomas, K. Abrahamsson, Chris Boxe, A. Granfors, A. E. Jones, M. D. King, A. Saiz-Lopez, P. B. Shepson, J. Sodeau, D. W. Toohey, C. Toubin, R. Von Glasow, S. N. Wren, X. Yang

Publications and Research

The role of ice in the formation of chemically active halogens in the environment requires a full understanding because of its role in atmospheric chemistry, including controlling the regional atmospheric oxidizing capacity in specific situations. In particular, ice and snow are important for facilitating multiphase oxidative chemistry and as media upon which marine algae live. This paper reviews the nature of environmental ice substrates that participate in halogen chemistry, describes the reactions that occur on such substrates, presents the field evidence for ice-mediated halogen activation, summarizes our best understanding of ice-halogen activation mechanisms, and describes the current state of modeling …


Temporal Changes In Collagen Cross-Links In Spontaneous Articular Cartilage Repair, Masahiko Terajima, Sheela Damle, Madhuri Penmatsa, Paul West, Mathias Bostrom, Chisa Hidaka, Mitsuo Yamauchi, Nancy Pleshko Jul 2012

Temporal Changes In Collagen Cross-Links In Spontaneous Articular Cartilage Repair, Masahiko Terajima, Sheela Damle, Madhuri Penmatsa, Paul West, Mathias Bostrom, Chisa Hidaka, Mitsuo Yamauchi, Nancy Pleshko

Publications and Research

Objective: Little is known about how the biochemical properties of collagen change during tissue regeneration following cartilage damage. In the current study, temporal changes in cartilage repair tissue biochemistry were assessed in a rabbit osteochondral defect. Design: Bilateral full-thickness 3-mm osteochondral trochlear groove defects were created in 54 adult male skeletally mature New Zealand white rabbits, and tissue repair was monitored over 16 weeks. Collagen content, cross-links, lysyl hydroxylation, gene expression, histological grading, and Fourier transform infrared analyses were performed at 2, 4, 6, 8, 12, and 16 weeks. Results: Defect fill occurred at ~4 weeks postinjury; however, histological grading …


Optimal Control Of Katabatic Flows Within Canopies, Hongbin Chen, Chuixiang Yi Jul 2012

Optimal Control Of Katabatic Flows Within Canopies, Hongbin Chen, Chuixiang Yi

Publications and Research

What slope angle favours the development of katabatic flow is still an open question. Some studies have clarified that katabatic winds are stronger on steep slopes, while others have demonstrated that katabatic winds are stronger on gentle slopes. Here, we explore the control mechanisms of katabatic flow using a simplified theoretical model in an attempt to clarify the causes of the paradoxical findings. Our results indicate that optimal conditions for katabatic flows within canopies are synergistically controlled by terrain angle, canopy structure and thermal condition through a simple equation:

LcVT-2 sin3 α = b,

where …


Taking Responsibility: The Multiple And Shifting Positions Of Social Justice Educators, Debbie Sonu, Rachel Oppenheim, Shira Epstein, Ruchi Agarwal Jun 2012

Taking Responsibility: The Multiple And Shifting Positions Of Social Justice Educators, Debbie Sonu, Rachel Oppenheim, Shira Epstein, Ruchi Agarwal

Publications and Research

In this article, we present a qualitative multi-case study of three beginning elementary teachers working in New York City and describe the distinct ways in which each articulates her responsibility to teach a social justice-oriented education. We employ positioning theory to examine how teachers narrate their relationship to the concept of social justice and how this relates to the ways in which they identify themselves and others as capable and qualified to engage in such work. We find that responsibility to teach for social justice is often delegated based on a perception of experiences with injustice and wonder how this …


A Novel Approach In Teaching Stem Subjects Through Cross-Departmental Collaboration In Capstone Courses, Iem Heng, Andy S. Zhang, Farrukh Zia Jun 2012

A Novel Approach In Teaching Stem Subjects Through Cross-Departmental Collaboration In Capstone Courses, Iem Heng, Andy S. Zhang, Farrukh Zia

Publications and Research

In today’s higher education, use of state of the art technology in the classroom and laboratory plays a vital role in hands-on cross-disciplinary activities and demonstration for students to learn the interconnection of STEM (Science, Technology, Engineering and Mathematics) concepts. To implement these activities, the capstone courses present an ideal opportunity for cross-departmental collaboration. The hands-on robotic design project is introduced in the capstone courses to teach interconnected STEM concepts. This type of project, which has proven very effective in engaging students, is used in many areas of technical courses as hands-on activities and demonstration and, in addition, lab work. …


Utilizing Project-Based Multidisciplinary Design Activities To Enhance Stem Education, Andy S. Zhang, Farrukh Zia, Iem Heng, Sidi Berri Jun 2012

Utilizing Project-Based Multidisciplinary Design Activities To Enhance Stem Education, Andy S. Zhang, Farrukh Zia, Iem Heng, Sidi Berri

Publications and Research

This paper discusses the use of project-based interdisciplinary design activities to enhance the STEM education in City Tech’s School of Technology and Design. STEM education has been a key in producing qualified individuals to work in today’s fast paced, highly competitive companies. Unfortunately, the supply of qualified workforce has been reduced due to the steady drop of enrollment of college and high school students in STEM related fields for the past twenty years. To tackle the dwindling enrollment of STEM students and low quality of STEM graduates, in a report submitted to Congress in 2007, the National Science Board suggested …


A Conative Educational Model For An Intervention Program In Obese Youth, Jérémy Vanhelst, Laurent Béghin, Paul Stephen Fardy, Gilles Bui-Xuan, Jacques Mikulovic Jun 2012

A Conative Educational Model For An Intervention Program In Obese Youth, Jérémy Vanhelst, Laurent Béghin, Paul Stephen Fardy, Gilles Bui-Xuan, Jacques Mikulovic

Publications and Research

Background Obesity in children has increased in recent years throughout the world and is associated with adverse health consequences. Early interventions, including appropriate pedagogy strategies, are important for a successful intervention program. The aim of this study was to assess changes in body mass index, the ability to perform sport activities, behavior in the classroom and academic performance following one year of a health-wellness intervention program in obese youth. Methods The CEMHaVi program included 37 obese children (19 girls and 18 boys). Participants received an intervention program consisting of physical activity and health education. Assessment included body mass index, academic …


Fundamental Limits On Wavelength, Efficiency And Yield Of The Charge Separation Triad, Alexander Punnoose, Liza Mcconnell, Wei Liu, Andrew C. Mutter, Ronald Koder Jun 2012

Fundamental Limits On Wavelength, Efficiency And Yield Of The Charge Separation Triad, Alexander Punnoose, Liza Mcconnell, Wei Liu, Andrew C. Mutter, Ronald Koder

Publications and Research

In an attempt to optimize a high yield, high efficiency artificial photosynthetic protein we have discovered unique energy and spatial architecture limits which apply to all light-activated photosynthetic systems. We have generated an analytical solution for the time behavior of the core three cofactor charge separation element in photosynthesis, the photosynthetic cofactor triad, and explored the functional consequences of its makeup including its architecture, the reduction potentials of its components, and the absorption energy of the light absorbing primary-donor cofactor. Our primary findings are two: First, that a high efficiency, high yield triad will have an absorption frequency more than …


Crossing Over…Markov Meets Mendel, Saad Mneimneh May 2012

Crossing Over…Markov Meets Mendel, Saad Mneimneh

Publications and Research

Chromosomal crossover is a biological mechanism to combine parental traits. It is perhaps the first mechanism ever taught in any introductory biology class. The formulation of crossover, and resulting recombination, came about 100 years after Mendel's famous experiments. To a great extent, this formulation is consistent with the basic genetic findings of Mendel. More importantly, it provides a mathematical insight for his two laws (and corrects them). From a mathematical perspective, and while it retains similarities, genetic recombination guarantees diversity so that we do not rapidly converge to the same being. It is this diversity that made the study of …


Hohenberg-Kohn And Percus-Levy-Lieb Proofs Of Density-Functional Theory, Viraht Sahni, Xiao-Yin Pan May 2012

Hohenberg-Kohn And Percus-Levy-Lieb Proofs Of Density-Functional Theory, Viraht Sahni, Xiao-Yin Pan

Publications and Research

The premise of density-functional theory is that knowledge of the ground-state density uniquely determines the Hamiltonian, and thereby, via solution of the corresponding time-independent Schrodinger equation, all the properties of the system. The density therefore constitutes a basic variable of quantum mechanics. There are at present two paths from the density to the Hamiltonian: the Hohenberg and Kohn proof of the bijectivity between the external potential and the basic variable, and the Percus, Levy, and Lieb constrained-search proof. We argue the Hohenberg- and Kohn-type proof to be the more fundamental, and that this is the case in general when both …


Cost Effective Malaria Risk Control Using Remote Sensing And Environmental Data, Md Zahidur Rahman, Leonid Roytman, Abdel Hamid Kadik May 2012

Cost Effective Malaria Risk Control Using Remote Sensing And Environmental Data, Md Zahidur Rahman, Leonid Roytman, Abdel Hamid Kadik

Publications and Research

Malaria transmission in many part of the world specifically in Bangladesh and southern African countries is unstable and epidemic. An estimate of over a million cases is reported annually. Malaria is heterogeneous, potentially due to variations in ecological settings, socio-economic status, land cover, and agricultural practices. Malaria control only relies on treatment and supply of bed networks. Drug resistance to these diseases is widespread. Vector control is minimal. Malaria control in those countries faces many formidable challenges such as inadequate accessibility to effective treatment, lack of trained manpower, inaccessibility of endemic areas, poverty, lack of education, poor health infrastructure and …


Twenty Years After: Armenian Research Libraries Today, D. Aram Donabedian, John Carey, Arshak Balayan May 2012

Twenty Years After: Armenian Research Libraries Today, D. Aram Donabedian, John Carey, Arshak Balayan

Publications and Research

Since achieving statehood in 1991, Armenia has faced major economic and political obstacles which have significantly affected the nation’s research libraries. This research paper will quantitatively and qualitatively examine the challenges facing Armenian research libraries just over twenty years after the collapse of the Soviet Union. Specifically, the authors analyze their interviews with five library administrators at five major institutions, respectively. These include Yerevan State University Library, the National Library of Armenia, the Fundamental Scientific Library of the National Academy of Sciences of Armenia, the Republican Scientific-Medical Library of Armenia, and the Papazian Library of the American University of Armenia. …


Pointcut Rejuvenation: Recovering Pointcut Expressions In Evolving Aspect-Oriented Software, Raffi Khatchadourian, Phil Greenwood, Awais Rashid, Harry Xu May 2012

Pointcut Rejuvenation: Recovering Pointcut Expressions In Evolving Aspect-Oriented Software, Raffi Khatchadourian, Phil Greenwood, Awais Rashid, Harry Xu

Publications and Research

Pointcut fragility is a well-documented problem in Aspect-Oriented Programming; changes to the base code can lead to join points incorrectly falling in or out of the scope of pointcuts. In this paper, we present an automated approach that limits fragility problems by providing mechanical assistance in pointcut maintenance. The approach is based on harnessing arbitrarily deep structural commonalities between program elements corresponding to join points selected by a pointcut. The extracted patterns are then applied to later versions to offer suggestions of new join points that may require inclusion. To illustrate that the motivation behind our proposal is well founded, …


Validation Of Noaa-Interactive Multisensor Snow And Ice Mapping System (Ims) By Comparison With Ground-Based Measurements Over Continental United States, Christine Chen, Tarendra Lakhankar, Peter Romanov, Sean Helfrich, Al Powell, Reza Khanbilvardi Apr 2012

Validation Of Noaa-Interactive Multisensor Snow And Ice Mapping System (Ims) By Comparison With Ground-Based Measurements Over Continental United States, Christine Chen, Tarendra Lakhankar, Peter Romanov, Sean Helfrich, Al Powell, Reza Khanbilvardi

Publications and Research

In this study, daily maps of snow cover distribution and sea ice extent produced by NOAA’s interactive multisensor snow and ice mapping system (IMS) were validated using in situ snow depth data from observing stations obtained from NOAA’s National Climatic Data Center (NCDC) for calendar years 2006 to 2010. IMS provides daily maps of snow and sea ice extent within the Northern Hemisphere using data from combination of geostationary and polar orbiting satellites in visible, infrared and microwave spectrums. Statistical correspondence between the IMS and in situ point measurements has been evaluated assuming that ground measurements are discrete and continuously …


Faculty As Undergraduate Research Mentors For Students Of Color: Taking Into Account The Costs, Joni Schwartz Apr 2012

Faculty As Undergraduate Research Mentors For Students Of Color: Taking Into Account The Costs, Joni Schwartz

Publications and Research

This article is based on the findings of a 2-year study that examined the nature of effective faculty/student undergraduate research (UR) science, technology, engineering, and mathematics (STEM) relationships. The study site was a large urban public college where three fourths of all incoming freshmen receive need-based aid; and although not a historically Black college or university (HBCU), 85% are students of color. The college offers 2- and 4-year STEM degree programs. Utilizing cultural historical activity theory (CHAT) as both a theoretical and methodological framework, this phenomenological study employed semistructured interviews, written surveys, and member checking to understand four paired faculty/student …


The Mathematics Portfolio: An Alternative Tool To Evaluate Students’ Progress, Marla A. Sole Apr 2012

The Mathematics Portfolio: An Alternative Tool To Evaluate Students’ Progress, Marla A. Sole

Publications and Research

This article describes the need for more thorough and varied forms of assessment to evaluate students’ level of understanding in mathematics. Portfolios are one type of assessment tool that, when added to a teacher’s repertoire can improve students’ comprehension and retention and enable students to monitor their own progress and to take more responsibility for their own learning. Portfolio assignments can also help students and teachers to detect and remedy weaknesses and misunderstandings and can increase students’ self-confidence in mathematics. This article discusses what a portfolio is, gives an example of a unit portfolio used in an undergraduate Finite Mathematics …


Estimation Of Phosphorus Bioavailability In The Water Column Of The Bronx River, New York, Jingyu Wang, Hari K. Pant Apr 2012

Estimation Of Phosphorus Bioavailability In The Water Column Of The Bronx River, New York, Jingyu Wang, Hari K. Pant

Publications and Research

Phosphorus (P) is a primary limiting nutrient in rivers and streams, and excessive P results in eutrophication of freshwater systems, in turn, excessive algal growth/toxic algal blooms, oxygen depletion, and water quality degradation. This study analyzed P pool, and hydrolysis of organic P (OP) by native phosphatases (NPase) in the water samples collected in the Bronx River. The soluble reactive P (SRP) of most of the sites’ water collected in 2006 and 2007 were higher (average 67 µg·L–1 and 68 µg·L–1, respectively) than the US Environmental Protection Agency’s (EPA) standard of 15 µg·L–1. The SRP% (SRP/TP%) average was 27% in …


Empirical Mapping Of Suitability To Dengue Fever In Mexico Using Species Distribution Modeling, Elia Machado Apr 2012

Empirical Mapping Of Suitability To Dengue Fever In Mexico Using Species Distribution Modeling, Elia Machado

Publications and Research

Dengue is considered the most important vector borne virus disease worldwide placing some 2.5 billion people at risk globally. Despite the public health concern about dengue fever, spatially explicit suitability assessments for this disease are limited due to data restrictions and the challenges posed by the complexity of the interactions among its risk factors, which involve social, economic and ecological processes.

This paper demonstrates an empirical approach to identify suitable areas for dengue fever using species distribution modeling, and evaluates the relative contribution of climatic and socio-economic factors as dengue fever suitability determinants. Several models showing the potential distribution of …


Introducing Aerospace Engineering To High And Middle Schools, Sean Pratt, Yapah Berry, Olivia Reed, Gaffar Gailani Apr 2012

Introducing Aerospace Engineering To High And Middle Schools, Sean Pratt, Yapah Berry, Olivia Reed, Gaffar Gailani

Publications and Research

No abstract provided.


From Art On The Wall To Something For All: How An Academic Library Turned Its Art Collection Into A Campus Attraction, Miriam B. Deutch, Jill Cirasella Apr 2012

From Art On The Wall To Something For All: How An Academic Library Turned Its Art Collection Into A Campus Attraction, Miriam B. Deutch, Jill Cirasella

Publications and Research

An important feature of the Brooklyn College Library is its art collection, the college’s only permanent art collection. In this article, we explain how the library came to have an art collection; how we supplemented the collection with museum-style wall labels, an online catalog, and an audio tour; and how we promoted the collection and sparked student creativity with an annual art contest. We pay particular attention to the decisions and details that might help other libraries working on similar projects.


1112+3548_Nir_Spex, J. Patience Apr 2012

1112+3548_Nir_Spex, J. Patience

Publications and Research

No abstract provided.


From Art On The Wall To Something For All: How An Academic Library Turned Its Art Collection Into A Campus Attraction, Jill Cirasella, Miriam Deutch Apr 2012

From Art On The Wall To Something For All: How An Academic Library Turned Its Art Collection Into A Campus Attraction, Jill Cirasella, Miriam Deutch

Publications and Research

An important feature of the Brooklyn College Library is its art collection, the college’s only permanent art collection. In this article, we explain how the library came to have an art collection; how we supplemented the collection with museum-style wall labels, an online catalog, and an audio tour; and how we promoted the collection and sparked student creativity with an annual art contest. We pay particular attention to the decisions and details that might help other libraries working on similar projects.


Correlated Components Of Ongoing Eeg Point To Emotionally Laden Attention – A Possible Marker Of Engagement?, Jacek P. Dmochowski, Paul Sajda, Joao Dias, Lucas C. Parra Mar 2012

Correlated Components Of Ongoing Eeg Point To Emotionally Laden Attention – A Possible Marker Of Engagement?, Jacek P. Dmochowski, Paul Sajda, Joao Dias, Lucas C. Parra

Publications and Research

Recent evidence from functional magnetic resonance imaging suggests that cortical hemodynamic responses coincide in different subjects experiencing a common naturalistic stimulus. Here we utilize neural responses in the electroencephalogram (EEG) evoked by multiple presentations of short film clips to index brain states marked by high levels of correlation within and across subjects. We formulate a novel signal decomposition method which extracts maximally correlated signal components from multiple EEG records. The resulting components capture correlations down to a one-second time resolution, thus revealing that peak correlations of neural activity across viewings can occur in remarkable correspondence with arousing moments of the …


Rational Design And Characterization Of D-Phe-Pro-D-Arg-Derived Direct Thrombin Inhibitors, Ana C. Figueiredo, Christina C. Clement, Sheuli Zakia, Julian Gingold, Manfred Philipp, Pedro J.B. Pereira Mar 2012

Rational Design And Characterization Of D-Phe-Pro-D-Arg-Derived Direct Thrombin Inhibitors, Ana C. Figueiredo, Christina C. Clement, Sheuli Zakia, Julian Gingold, Manfred Philipp, Pedro J.B. Pereira

Publications and Research

The tremendous social and economic impact of thrombotic disorders, together with the considerable risks associated to the currently available therapies, prompt for the development of more efficient and safer anticoagulants. Novel peptide-based thrombin inhibitors were identified using in silico structure-based design and further validated in vitro. The best candidate compounds contained both l- and d-amino acids, with the general sequence d-Phe(P3)-Pro(P2)-d-Arg(P1)-P1'-CONH2. The P1' position was scanned with l- and d-isomers of natural or unnatural amino acids, covering the major chemical classes. The most potent non-covalent and proteolysis-resistant inhibitors contain small hydrophobic or polar amino acids (Gly, Ala, Ser, Cys, Thr) …


Advances In Ultrafast Time Resolved Fluorescence Physics For Cancer Detection In Optical Biopsy, R. R. Alfano Mar 2012

Advances In Ultrafast Time Resolved Fluorescence Physics For Cancer Detection In Optical Biopsy, R. R. Alfano

Publications and Research

We discuss the use of time resolved fluorescence spectroscopy to extract fundamental kinetic information on molecular species in tissues. The temporal profiles reveal the lifetime and amplitudes associated with key active molecules distinguishing the local spectral environment of tissues. The femtosecond laser pulses at 310 nm excite the tissue. The emission profile at 340 nm from tryptophan is non-exponential due to the micro-environment. The slow and fast amplitudes and lifetimes of emission profiles reveal that cancer and normal states can be distinguished. Time resolved optical methods offer a new cancer diagnostic modality for the medical community.