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Full-Text Articles in Physical Sciences and Mathematics

Allometric Scaling And Resource Limitations Model Of Tree Heights: Part 1. Model Optimization And Testing Over Continental Usa, Yuli Shi, Sungho Choi, Xiliang Ni, Sangram Ganguly, Gong Zhang, Hieu V. Duong, Michael A. Lefsky, Marc Simard, Sassan S. Saatchi, Shihyan Lee, Wenge Ni-Meister, Shilong Piao, Chunxiang Cao, Ramakrishna R. Nemani, Ranga B. Myneni Jan 2013

Allometric Scaling And Resource Limitations Model Of Tree Heights: Part 1. Model Optimization And Testing Over Continental Usa, Yuli Shi, Sungho Choi, Xiliang Ni, Sangram Ganguly, Gong Zhang, Hieu V. Duong, Michael A. Lefsky, Marc Simard, Sassan S. Saatchi, Shihyan Lee, Wenge Ni-Meister, Shilong Piao, Chunxiang Cao, Ramakrishna R. Nemani, Ranga B. Myneni

Publications and Research

A methodology to generate spatially continuous fields of tree heights with an optimized Allometric Scaling and Resource Limitations (ASRL) model is reported in this first of a multi-part series of articles. Model optimization is performed with the Geoscience Laser Altimeter System (GLAS) waveform data. This methodology is demonstrated by mapping tree heights over forested lands in the continental USA (CONUS) at 1 km spatial resolution. The study area is divided into 841 eco-climatic zones based on three forest types, annual total precipitation classes (30 mm intervals) and annual average temperature classes (2 °C intervals). Three model parameters (area of single …


Entropy And The Complexity Of Graphs Revisited, Abbe Mowshowitz, Matthias Dehmer Mar 2012

Entropy And The Complexity Of Graphs Revisited, Abbe Mowshowitz, Matthias Dehmer

Publications and Research

This paper presents a taxonomy and overview of approaches to the measurement of graph and network complexity. The taxonomy distinguishes between deterministic (e.g., Kolmogorov complexity) and probabilistic approaches with a view to placing entropy-based probabilistic measurement in context. Entropy-based measurement is the main focus of the paper. Relationships between the different entropy functions used to measure complexity are examined; and intrinsic (e.g., classical measures) and extrinsic (e.g., Körner entropy) variants of entropy-based models are discussed in some detail.


Group 11 Metal Compounds With Tripodal Bis(Imidazole) Thioether Ligands. Applications As Catalysts In The Oxidation Of Alkenes And As Antimicrobial Agents, Fangwei Liu, Reema Anis, Eunmi Hwang, Rafael Ovalle, Armando Varela-Ramírez, Renato J. Aguilera, María Contel Aug 2011

Group 11 Metal Compounds With Tripodal Bis(Imidazole) Thioether Ligands. Applications As Catalysts In The Oxidation Of Alkenes And As Antimicrobial Agents, Fangwei Liu, Reema Anis, Eunmi Hwang, Rafael Ovalle, Armando Varela-Ramírez, Renato J. Aguilera, María Contel

Publications and Research

New group 11 metal complexes have been prepared using the previously described tripodal bis(imidazole) thioether ligand (N-methyl-4,5-diphenyl-2- imidazolyl)2C(OMe)C(CH3)2S(tert-Bu) ({BITOMe,StBu}, 2). The pincer ligand offers a N2S donor atom set that can be used to coordinate the group 11 metals in different oxidation states [AuI , AuIII, AgI , CuI and CuII]. Thus the new compounds [Au{BITOMe,StBu}Cl][AuCl4]2 (3), [Au{BITOMe,StBu}Cl] (4), [Ag{BITOMe,StBu}X] (X = OSO2CF3 - 5, PF6 - 6) and [Cu{BITOMe,StBu}Cl2] (7) have been synthesized from reaction of 2 with the appropriate metal precursors, and characterized in solution. While attempting characterization in the solid state of 3, single crystals of the …


Polycationic Glycosides, Robert Engel, Ishrat Ghani, Diego Montenegro, Marie Thomas, Barbara Klaritch-Vrana, Alejandra Castaño, Laura Friedman, Jay Leb, Leah Rothman, Heidi Lee, Craig Capodiferro, Daniel Ambinder, Eve Cere, Christopher Awad, Faiza Sheikh, Jaimelee Rizzo, Lisa-Marie Nisbett, Erika Testani, Karin Melkonian Feb 2011

Polycationic Glycosides, Robert Engel, Ishrat Ghani, Diego Montenegro, Marie Thomas, Barbara Klaritch-Vrana, Alejandra Castaño, Laura Friedman, Jay Leb, Leah Rothman, Heidi Lee, Craig Capodiferro, Daniel Ambinder, Eve Cere, Christopher Awad, Faiza Sheikh, Jaimelee Rizzo, Lisa-Marie Nisbett, Erika Testani, Karin Melkonian

Publications and Research

Cationic lipids have long been known to serve as antibacterial and antifungal agents. Prior efforts with attachment of cationic lipids to carbohydrate-based surfaces have suggested the possibility that carbohydrate-attached cationic lipids might serve as antibacterial and antifungal pharmaceutical agents. Toward the understanding of this possibility, we have synthesized several series of cationic lipids attached to a variety of glycosides with the intent of generating antimicrobial agents that would meet the requirement for serving as a pharmaceutical agent, specifically that the agent be effective at a very low concentration as well as being biodegradable within the organism being treated. The initial …


The Mycobacterium Tuberculosis Drugome And Its Polypharmacological Implications, Sarah L. Kinnings, Li Xie, Kingston H. Fung, Richard M. Jackson, Lei Xie, Phillip E. Bourne Nov 2010

The Mycobacterium Tuberculosis Drugome And Its Polypharmacological Implications, Sarah L. Kinnings, Li Xie, Kingston H. Fung, Richard M. Jackson, Lei Xie, Phillip E. Bourne

Publications and Research

We report a computational approach that integrates structural bioinformatics, molecular modelling and systems biology to construct a drug-target network on a structural proteome-wide scale. The approach has been applied to the genome of Mycobacterium tuberculosis (M.tb), the causative agent of one of today’s most widely spread infectious diseases. The resulting drug-target interaction network for all structurally characterized approved drugs bound to putative M.tb receptors, we refer to as the ‘TB-drugome’. The TB-drugome reveals that approximately one-third of the drugs examined have the potential to be repositioned to treat tuberculosis and that many currently unexploited M.tb receptors may be chemically druggable …


Drug Off-Target Effects Predicted Using Structural Analysis In The Context Of A Metabolic Network Model, Roger L. Chang, Lei Xie, Philip E. Bourne, Bernhard O. Palsson Sep 2010

Drug Off-Target Effects Predicted Using Structural Analysis In The Context Of A Metabolic Network Model, Roger L. Chang, Lei Xie, Philip E. Bourne, Bernhard O. Palsson

Publications and Research

Recent advances in structural bioinformatics have enabled the prediction of protein-drug off-targets based on their ligand binding sites. Concurrent developments in systems biology allow for prediction of the functional effects of system perturbations using large-scale network models. Integration of these two capabilities provides a framework for evaluating metabolic drug response phenotypes in silico. This combined approach was applied to investigate the hypertensive side effect of the cholesteryl ester transfer protein inhibitor torcetrapib in the context of human renal function. A metabolic kidney model was generated in which to simulate drug treatment. Causal drug off-targets were predicted that have previously been …


A Multidimensional Strategy To Detect Polypharmacological Targets In The Absence Of Structural And Sequence Homology, Jacob D. Durrant, Rommie E. Amaro, Lei Xie, Michael D. Urbaniak, Michael A. J. Ferguson, Antti Haapalainen, Zhijun Chen, Anne Marie Di Guilmi, Frank Wunder, Philip E. Bourne, J. Andrew Mccammon Jan 2010

A Multidimensional Strategy To Detect Polypharmacological Targets In The Absence Of Structural And Sequence Homology, Jacob D. Durrant, Rommie E. Amaro, Lei Xie, Michael D. Urbaniak, Michael A. J. Ferguson, Antti Haapalainen, Zhijun Chen, Anne Marie Di Guilmi, Frank Wunder, Philip E. Bourne, J. Andrew Mccammon

Publications and Research

Conventional drug design embraces the ‘‘one gene, one drug, one disease’’ philosophy. Polypharmacology, which focuses on multi-target drugs, has emerged as a new paradigm in drug discovery. The rational design of drugs that act via polypharmacological mechanisms can produce compounds that exhibit increased therapeutic potency and against which resistance is less likely to develop. Additionally, identifying multiple protein targets is also critical for side-effect prediction. One third of potential therapeutic compounds fail in clinical trials or are later removed from the market due to unacceptable side effects often caused by off-target binding. In the current work, we introduce a multidimensional …


Correlating Molecular Phylogeny With Venom Apparatus Occurrence In Panamic Auger Snails (Terebridae), Mandë Holford, Nicolas Puillandre, Maria Vittoria Modica, Maren Watkins, Rachel Collin, Eldredge Bermingham, Baldomero M. Olivera Nov 2009

Correlating Molecular Phylogeny With Venom Apparatus Occurrence In Panamic Auger Snails (Terebridae), Mandë Holford, Nicolas Puillandre, Maria Vittoria Modica, Maren Watkins, Rachel Collin, Eldredge Bermingham, Baldomero M. Olivera

Publications and Research

Central to the discovery of neuroactive compounds produced by predatory marine snails of the superfamily Conoidea (cone snails, terebrids, and turrids) is identifying those species with a venom apparatus. Previous analyses of western Pacific terebrid specimens has shown that some Terebridae groups have secondarily lost their venom apparatus. In order to efficiently characterize terebrid toxins, it is essential to devise a key for identifying which species have a venom apparatus. The findings presented here integrate molecular phylogeny and the evolution of character traits to infer the presence or absence of the venom apparatus in the Terebridae. Using a combined dataset …


Strokes Of Existence: The Connection Of All Things, Mari Gorman Jan 2007

Strokes Of Existence: The Connection Of All Things, Mari Gorman

Graduate Student Publications and Research

Acted or real—and all life is real whether one is acting or not—the common denominator and consistent, ubiquitous reality of life and all behavior is that it manifests in the form of relationships on all scales. But what is a relationship? Until now, the answer to this question has not been sufficiently known. As a result of many years of empirical research that began with the aim of discovering what is going on in a gifted actor when s/he is playing a character that can be observed and experienced as a living, intuitive being, and based on the knowledge that …