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Full-Text Articles in Physical Sciences and Mathematics

A Convenient And Efficient Synthesis Of (S)-Lysine And (S)-Arginine Homologues Via Olefin Cross-Metathesis, Timothy P. Boyle, John B. Bremner, Jonathan A. Coates, Paul A. Keller, Stephen G. Pyne Aug 2010

A Convenient And Efficient Synthesis Of (S)-Lysine And (S)-Arginine Homologues Via Olefin Cross-Metathesis, Timothy P. Boyle, John B. Bremner, Jonathan A. Coates, Paul A. Keller, Stephen G. Pyne

Paul Keller

A convenient five step synthesis of (S)-homolysine, incorporating a key olefin cross-metathesis step in the chain extension methodology, has been developed, together with a six step related synthesis of a new homologue of arginine, (S)-bishomoarginine.


Antimalarial Activity Of 2,4-Diaminopyrimidines, J. Morgan, R. Haritakul, Paul A. Keller Aug 2010

Antimalarial Activity Of 2,4-Diaminopyrimidines, J. Morgan, R. Haritakul, Paul A. Keller

Paul Keller

A series of 2,4- and 4,6-diaminopyrimidines were prepared and evaluated for their in vitro antimalarial activity. Of the 12 compounds tested 7 showed reasonable activity with 1 having a sub-micromolar IC50.


Aryl Nitro Reduction With Iron Powder Or Stannous Chloride Under Ultrasonic Irradiation, A. B. Gamble, James A. Garner, Christopher Gordon, S. M. J. O'Conner, Paul A. Keller Aug 2010

Aryl Nitro Reduction With Iron Powder Or Stannous Chloride Under Ultrasonic Irradiation, A. B. Gamble, James A. Garner, Christopher Gordon, S. M. J. O'Conner, Paul A. Keller

Paul Keller

The selective reduction of aryl nitro compounds in the presence of sensitive functionalities, including halide, carbonyl, nitrile and ester substituents under ultrasonic irradiation at 35 kHz is reported in yields of 39-98%. Iron powder proved superior to stannous chloride with high tolerance of sensitive functional groups and high yields of the desired aryl amines in relatively short reaction times. Simple experimental procedure and purification also make the iron reduction of aryl nitro compounds advantageous over other methods of reduction.


Control Of Hiv Through The Inhibition Of Hiv-1 Integrase: A Medicinal Chemistry Perspective, Christopher Gordon, R. Griffith, Paul A. Keller Aug 2010

Control Of Hiv Through The Inhibition Of Hiv-1 Integrase: A Medicinal Chemistry Perspective, Christopher Gordon, R. Griffith, Paul A. Keller

Paul Keller

This article reviews the current status of classes of HIV-1 integrase enzyme inhibitors. These classes include peptide-based inhibitors, natural products, polyhydroxylated aromatics, diketo acids, naphthyridines, and sulfonated compounds including sulfonic acids. Discussions of structure activity relationships are presented and include the current overview of the structure-based model, suitable for the further design and development. To date, the advances in the medicinal chemistry of HIV-1 integrase inhibitors have relied mostly on ligand-based designs leading to most displaying similar binding interactions within the active site or at the dimer interface. This paves the way for single enzyme mutations rendering entire compound classes …


The Prevention Of Preterm Labour – Corticotropin Releasing Hormone Type 1 Receptors As A Target For Drug Design And Development, Paul A. Keller, K. Kirkwood, J. Morgan, S. Westcott, A. Mccluskey Aug 2010

The Prevention Of Preterm Labour – Corticotropin Releasing Hormone Type 1 Receptors As A Target For Drug Design And Development, Paul A. Keller, K. Kirkwood, J. Morgan, S. Westcott, A. Mccluskey

Paul Keller

The role of the corticotropin releasing hormone in the onset of labour and the subsequent medicinal chemistry implications of CRH antagonists for the prevention of premature birth, and identification of the CRH type 1 receptor as the target for this drug design, are reviewed here.


A New Methodology For The Simulation Of Flexible Protein – Ligand Interactions, James A. Garner, John Deadman, David I. Rhodes, Renate Griffith, Paul A. Keller Aug 2010

A New Methodology For The Simulation Of Flexible Protein – Ligand Interactions, James A. Garner, John Deadman, David I. Rhodes, Renate Griffith, Paul A. Keller

Paul Keller

A methodology has been developed for the simulation of induced fit between a ligand and its target protein. It utilizes constrained molecular dynamics where atoms determined to be immobile from difference distance matrix studies are fixed. Application of this methodology to HIV-1 reverse transcriptase (RT) as the example target protein has demonstrated its robustness. Short simulation times are sufficient to achieve good refinement of docking poses resulting from exchange of structurally dissimilar inhibitors between crystal structures.


Corticotropin Releasing Hormone - A Gpcr Drug Target, C. Hemley, A. Mccluskey, Paul A. Keller Aug 2010

Corticotropin Releasing Hormone - A Gpcr Drug Target, C. Hemley, A. Mccluskey, Paul A. Keller

Paul Keller

Corticotrophin Releasing Hormone (CRH) is a primary hormone in the fight or flight response targeting a membrane bound G-protein coupled receptor (GPCR). Many people worldwide stand to benefit by the development of CRH agonists and antagonists for the treatment of anxiety and depression, with additional therapeutic targets including Alzheimer’s, pain and the prevention of premature birth: so why the delay in development? In this review, we will discuss not only CRH, related proteins, receptors and ligands, but some of the obstacles that have arisen, as well as strategies being pursued to overcome these problems in the pursuit of this GPCR …


Combining Structure-Based Drug Design And Pharmacophores, Renate Griffith, T. T. T. Luu, James A. Garner, Paul A. Keller Aug 2010

Combining Structure-Based Drug Design And Pharmacophores, Renate Griffith, T. T. T. Luu, James A. Garner, Paul A. Keller

Paul Keller

Development towards integrated computer-aided drug design methodologies is presented by utilising crystal structure complexes to produce structure-based pharmacophores. These novel pharmacophores represent the ligand features that are involved in interactions with the target protein, as well as the space around the ligand occupied by the protein. The protein-ligand complexes can also yield information about all interactions that ligands could potentially form with the binding site, as well as about the size of the binding cavity. Together, these describe a 'superligand', which can also be viewed as a pharmacophore. Various types of novel pharmacophores are discussed and compared, using HIV-1 Reverse …


2,4,6-Triphenyl­Aniline, Onome Ugono, Stephanie Cowin, Alicia M. Beatty Jul 2010

2,4,6-Triphenyl­Aniline, Onome Ugono, Stephanie Cowin, Alicia M. Beatty

Alicia Beatty

Individual mol­ecules of the title compound, C24H19N, do not participate in hydrogen-bonding inter­actions due to the steric bulk of the phenyl rings ortho to the amine. The dihedral angles between the central ring and the pendant rings are 68.26 (10), 55.28 (10) and 30.61 (11)°.


Is The Curvature Of The Flagellum Involved In The Apparent Cooperativity Of The Dynein Arms Along The "9+2" Axoneme?, Christian Cibert, Andrei Ludu Jun 2010

Is The Curvature Of The Flagellum Involved In The Apparent Cooperativity Of The Dynein Arms Along The "9+2" Axoneme?, Christian Cibert, Andrei Ludu

Andrei Ludu

In a recent study [Cibert, 2008. Journal of Theoretical Biology, 253, 74-89], by assuming that the walls of microtubules are involved in cyclic compression/dilation equilibriums as a consequence of their cyclic curvature of the axoneme, it was proposed that local adjustments of spatial frequencies of both dynein arms and beta-tubulin monomers facing series create propagation of joint probability waves of interaction (JPI) between these two necessary partners. Modeling the occurrence of these interactions along the entire length of an axoneme between each outer doublet pair (without programming any cooperative dialog between the molecular complexes) and the cyclic attachment of two …


Land From The Sea: The Mangrove Afforestation Program Of Bangladesh, Peter Saenger, N A. Siddiqi May 2010

Land From The Sea: The Mangrove Afforestation Program Of Bangladesh, Peter Saenger, N A. Siddiqi

Emeritus Professor Peter Saenger

The coastal areas of Bangladesh have a high cyclone frequency. The protection from cyclone damage afforded by the natural mangrove forests of the Sundarbans, led the Forest Department in 1966 to initiate a mangrove afforestation programme. These initial plantings proved highly successful in protecting and stabilizing coastal areas, and led to a large-scale mangrove afforestation initiative. To date, approximately 120 000 ha of mangroves have been planted. Nursery and planting techniques have been developed for the major species, while additional species are still being investigated. As a result of the extensive monospecific plantations, however, outbreaks of two major insect pest …


Do We Teach Disciplines Or Do We Teach Students?—What Difference Does It Make?, Marshall W. Gregory Apr 2010

Do We Teach Disciplines Or Do We Teach Students?—What Difference Does It Make?, Marshall W. Gregory

Marshall W. Gregory

The single most difficult notion for graduate students and new professors to grasp about teaching--and, indeed, many experienced teachers never grasp this point either--is that successful teaching to undergraduates has little to do with the degree of one's mastery of disciplinary knowledge.


Capturing Genetic Variation During Ecological Restorations: An Example From Kankakee Sands In Indiana, Rebecca W. Dolan, Deborah L. Marr, Andrew Schnabel Apr 2010

Capturing Genetic Variation During Ecological Restorations: An Example From Kankakee Sands In Indiana, Rebecca W. Dolan, Deborah L. Marr, Andrew Schnabel

Rebecca W. Dolan

Genetic variation in populations, both natural and restored, is usually considered crucial for response to short term environmental stresses and for long term evolutionary change. To have the best chance of successful long-term survival, restored populations should reflect the extant variation found in remnants, but restored sites may suffer from genetic bottlenecks as a result of founder effects. Kankakee Sands is a large-scale restoration being conducted by The Nature Conservancy (TNC) in northwestern Indiana. Our goal was to test for loss of genetic variation in restored plant populations by comparing them with TNC’s seed source nursery and with local remnant …


Capturing Genetic Variation During Ecological Restorations: An Example From Kankakee Sands In Indiana, Rebecca W. Dolan, Deborah L. Marr, Andrew Schnabel Apr 2010

Capturing Genetic Variation During Ecological Restorations: An Example From Kankakee Sands In Indiana, Rebecca W. Dolan, Deborah L. Marr, Andrew Schnabel

Rebecca W. Dolan

Genetic variation in populations, both natural and restored, is usually considered crucial for response to short term environmental stresses and for long term evolutionary change. To have the best chance of successful long-term survival, restored populations should reflect the extant variation found in remnants, but restored sites may suffer from genetic bottlenecks as a result of founder effects. Kankakee Sands is a large-scale restoration being conducted by The Nature Conservancy (TNC) in northwestern Indiana. Our goal was to test for loss of genetic variation in restored plant populations by comparing them with TNC’s seed source nursery and with local remnant …


Ecological Niche Modeling And Local Knowledge Predict New Populations Of Gymnocladus Assamicus A Critically Endangered Tree Species, Shaily Menon, Baharul I. Choudhury, M. Latif Khan, A. Townsend Peterson Apr 2010

Ecological Niche Modeling And Local Knowledge Predict New Populations Of Gymnocladus Assamicus A Critically Endangered Tree Species, Shaily Menon, Baharul I. Choudhury, M. Latif Khan, A. Townsend Peterson

Shaily Menon

Gymnocladus assamicus is a critically endangered tree species endemic to northeastern India. Local inhabitants traditionally used this species for a variety of purposes. However, rapid population declines led to the species being considered extinct, until fieldwork in 2004 to 2007 identified 14 discrete populations of 1 to 7 trees each. To overcome constraints on field surveys imposed by the region’s remoteness and rugged terrain, we targeted areas of further field inventories by estimating the potential distribution of the species. Ecological niche modeling enabled us to identify 26 sites which the model predicted to be highly suitable for the species’ occurrence. …


Comparative Genetics Of Seven Plants Endemic To Florida’S Lake Wales Ridge, Eric S. Menges, Rebecca W. Dolan, Rebecca Yahr, Doria R. Gordan Apr 2010

Comparative Genetics Of Seven Plants Endemic To Florida’S Lake Wales Ridge, Eric S. Menges, Rebecca W. Dolan, Rebecca Yahr, Doria R. Gordan

Rebecca W. Dolan

Here we submit that mathematical tools used in population viability analysis can be used in conjunction with floristic and faunistic surveys to predict changes in biogeographic range. We illustrate our point by summarizing the results of a demographic study of Lobelia boykinii. In this study we used deterministic and stochastic matrix models to estimate the growth rate and to predict the time to extinction for three populations growing in the Carolina bays. The stochastic model better discriminated among the fates of the three populations. It predicted extinction for two populations in the next 25 years but no extinction of the …


Was Jesus Illegitimate? The Evidence Of His Social Interactions, James F. Mcgrath Apr 2010

Was Jesus Illegitimate? The Evidence Of His Social Interactions, James F. Mcgrath

James F. McGrath

This article examines the social status of the historical Jesus in relation to recent studies that place Jesus into the social category of an illegitimate child. After surveying the evidence with respect to the situation of such individuals in first century Mediterranean and Jewish society, we shall proceed to examine whether Jesus' implied social status (as evidenced by accounts of his adult social interactions) coheres with what one would expect in the case of someone who bore the stigma of that status. Our study suggests that the scandal caused by Jesus' association with the marginalized clearly implies that he did …


Was Jesus Illegitimate? The Evidence Of His Social Interactions, James F. Mcgrath Apr 2010

Was Jesus Illegitimate? The Evidence Of His Social Interactions, James F. Mcgrath

James F. McGrath

This article examines the social status of the historical Jesus in relation to recent studies that place Jesus into the social category of an illegitimate child. After surveying the evidence with respect to the situation of such individuals in first century Mediterranean and Jewish society, we shall proceed to examine whether Jesus' implied social status (as evidenced by accounts of his adult social interactions) coheres with what one would expect in the case of someone who bore the stigma of that status. Our study suggests that the scandal caused by Jesus' association with the marginalized clearly implies that he did …


The Clute Holotypes And The Herbarium Of Willard Nelson Clute In The Friesner Herbarium Of Butler University, Rebecca W. Dolan Apr 2010

The Clute Holotypes And The Herbarium Of Willard Nelson Clute In The Friesner Herbarium Of Butler University, Rebecca W. Dolan

Rebecca W. Dolan

The herbarium of Willard Nelson Clute is housed in the Friesner Herbarium (BUT). Clute, co-founder of the American Fern Society, was a staff member at Butler University in the 1920's and 30's. His collection of ferns and fern allies from the tum of the century is significant for its selected regional coverage and for type specimens of taxa described by Clute and other fern specialists of the day.


Rethinking Mechanistic Explanation, Stuart Glennan Apr 2010

Rethinking Mechanistic Explanation, Stuart Glennan

Stuart Glennan

Philosophers of science typically associate the causal-mechanical view of scientific explanation with the work of Railton and Salmon. In this paper I shall argue that the defects of this view arise from an inadequate analysis of the concept of mechanism. I contrast Salmon's account of mechanisms in terms of the causal nexus with my own account of mechanisms, in which mechanisms are viewed as complex systems. After describing these two concepts of mechanism, I show how the complex-systems approach avoids certain objections to Salmon's account of causal-mechanical explanation. I conclude by discussing how mechanistic explanations can provide understanding by unification.


Genetic Variation In Past And Current Landscapes: Conservation Implications Based On Six Endemic Florida Scrub Plants, Eric S. Menges, Rebecca W. Dolan, Robert Pickert, Rebecca Yahr, Doria R. Gordon Mar 2010

Genetic Variation In Past And Current Landscapes: Conservation Implications Based On Six Endemic Florida Scrub Plants, Eric S. Menges, Rebecca W. Dolan, Robert Pickert, Rebecca Yahr, Doria R. Gordon

Rebecca W. Dolan

If genetic variation is often positively correlated with population sizes and the presence of nearby populations and suitable habitats, landscape proxies could inform conservation decisions without genetic analyses. For six Florida scrub endemic plants (Dicerandra frutescens, Eryngium cuneifolium, Hypericum cumulicola, Liatris ohlingerae, Nolina brittoniana, and Warea carteri), we relate two measures of genetic variation, expected heterozygosity and alleles per polymorphic locus (APL), to population size and landscape variables. Presettlement areas were estimated based on soil preferences and GIS soils maps. Four species showed no genetic patterns related to population or landscape factors. The other two species showed significant but inconsistent …


Antimicrobial And Antioxidant Activities Of Essential Oil And Methanol Extract Of Jasminum Sambac From Djibouti, Fatou Abdoul-Latif, Prosper Edou, François Eba, Nabil Mohamed, Adwa Ali, Samatar Djama, Louis-Clément Obame, Mamoudou Hama Dicko Mar 2010

Antimicrobial And Antioxidant Activities Of Essential Oil And Methanol Extract Of Jasminum Sambac From Djibouti, Fatou Abdoul-Latif, Prosper Edou, François Eba, Nabil Mohamed, Adwa Ali, Samatar Djama, Louis-Clément Obame, Mamoudou Hama Dicko

Pr. Mamoudou H. DICKO, PhD

The essential oil of jasminum sambac from Djibouti was subjected to screening for their possible antioxidant activity by two complementary test systems, namely DPPH free radical scavenging and beta-carotene-linoleic acid assays. Butylated hydroxytoluene (BHT) was used as positive control in both test systems. In the DPPH test system, the IC50 value of essential oil and methanol extract were respectively 7.43 and 2.30 μg/ml. In the beta-carotene-linoleic acid system, oxidation was effectively inhibited by Jasminum sambac, the RAA value of essential oil and methanol extract were respectively 96.6 and 93.9%. When compared to BHT, the essential oil and methanol extract had …


Targeting Prostate Cancer Cells In Vivo Using A Rapidly Internalizing Novel Human Single-Chain Antibody Fragment., Arun K. Iyer Feb 2010

Targeting Prostate Cancer Cells In Vivo Using A Rapidly Internalizing Novel Human Single-Chain Antibody Fragment., Arun K. Iyer

Arun Iyer

Human antibodies targeting prostate cancer cell surface epitopes may be useful for imaging and therapy. The objective of this study was to evaluate the tumor targeting of an internalizing human antibody fragment, a small-size platform, to provide high contrast in a mouse model of human prostate carcinoma. METHODS: A prostate tumor-targeting single-chain antibody fragment (scFv), UA20, along with a nonbinding control scFv, N3M2, were labeled with (99m)Tc and evaluated for binding and rapid internalization into human prostate tumor cells in vitro and tumor homing in vivo using xenograft models. For the in vitro studies, the labeled UA20 scFv was incubated …


Beethoven: Patriotism And Social Justice, Fathi Habashi Feb 2010

Beethoven: Patriotism And Social Justice, Fathi Habashi

Fathi Habashi

The great composer Ludwig van Beethoven was not only an exceptional musician but also a man of great ideals who expressed social justice in his music


Functional Generalized Linear Models With Images As Predictors, Philip T. Reiss, R. Todd Ogden Feb 2010

Functional Generalized Linear Models With Images As Predictors, Philip T. Reiss, R. Todd Ogden

Philip T. Reiss

Functional principal component regression (FPCR) is a promising new method for regressing scalar outcomes on functional predictors. In this paper we present a theoretical justification for the use of principal components in functional regression. FPCR is then extended in two directions: from linear to the generalized linear modeling, and from univariate signal predictors to high-resolution image predictors. We show how to implement the method efficiently by adapting generalized additive model technology to the functional regression context. A technique is proposed for estimating simultaneous confidence bands for the coefficient function; in the neuroimaging setting, this yields a novel means to identify …


Photosynthesis In Silico: A Multimedia Cd-Rom Combining Animations, Simulations And Self-Paced Modules For Photosynthesis Education At All Tertiary Levels, Sharon A. Robinson, W. A. Russell, G. M.A. Netherwood Jan 2010

Photosynthesis In Silico: A Multimedia Cd-Rom Combining Animations, Simulations And Self-Paced Modules For Photosynthesis Education At All Tertiary Levels, Sharon A. Robinson, W. A. Russell, G. M.A. Netherwood

Sharon Robinson

Photosynthesis is a vital component of any undergraduate biology course. Despite its central importance in providing biochemical energy, fixed carbon and oxygen for all life on Earth, it remains an area which students find uninteresting and difficult to comprehend. This difficulty is compounded by problems with laboratory equipment for practical classes, which tends to be either expensive and complex, or simple and unreliable, making it extremely difficult to provide effective, hands-on teaching of photosynthesis to the large class sizes in undergraduate biology courses. A set of interactive, multimedia modules have been combined on a CD-ROM, which provides a new approach …


Cortical Underconnectivity Coupled With Preserved Visuospatial Cognition In Autism: Evidence From An Fmri Study Of An Embedded Figures Task, Saudamini Damarla, Timothy A. Keller, Rajesh K. Kana, Vladimir L. Cherkassky, Diane L. Williams, Nancy J. Minshew, Marcel Adam Just Dec 2009

Cortical Underconnectivity Coupled With Preserved Visuospatial Cognition In Autism: Evidence From An Fmri Study Of An Embedded Figures Task, Saudamini Damarla, Timothy A. Keller, Rajesh K. Kana, Vladimir L. Cherkassky, Diane L. Williams, Nancy J. Minshew, Marcel Adam Just

Marcel Adam Just

No abstract provided.


Biomechanical Analysis Of Gait Adaptation In The Nematode Caenorhabditis Elegans, Christopher Fang-Yen, M Wyart, J Xie, R Kawai, S Chen, T Kodger, Q Wen, A D T Samuel Dec 2009

Biomechanical Analysis Of Gait Adaptation In The Nematode Caenorhabditis Elegans, Christopher Fang-Yen, M Wyart, J Xie, R Kawai, S Chen, T Kodger, Q Wen, A D T Samuel

Christopher Fang-Yen

No abstract provided.


Knoor: Knowledge Repository Open Network., S M. Shafi, Nadim Akhtar Khan, Rosy Jan Dec 2009

Knoor: Knowledge Repository Open Network., S M. Shafi, Nadim Akhtar Khan, Rosy Jan

NADIM AKHTAR KHAN

The paper discusses KNoor (Knowledge Repository Open Network) which aims at harvesting and aggregating the scholarly products emanating from research and scientific institutions of Jammu & Kashmir. The paper highlights genesis, significance, cooperation and various modules of access etc with screen shots as a unique cooperative, multilingual repository of research papers, ETDs and conference proceedings of three premier institutes of valley (University of Kashmir, Sher-e-Kashmir Institute of Medical sciences, Sher-e-Kashmir University of Agricultural Sciences) in the first phase. It also discusses challenges and lessons learnt in the process with a view to help other institutions to advance the mission of …


Semiparametric Analysis Of Recurrent Events: Artificial Censoring, Truncation, Pairwise Estimation And Inference, Debashis Ghosh Dec 2009

Semiparametric Analysis Of Recurrent Events: Artificial Censoring, Truncation, Pairwise Estimation And Inference, Debashis Ghosh

Debashis Ghosh

The analysis of recurrent failure time data from longitudinal studies can be complicated by the presence of dependent censoring. There has been a substantive literature that has developed based on an artificial censoring device. We explore in this article the connection between this class of methods with truncated data structures. In addition, a new procedure is developed for estimation and inference in a joint model for recurrent events and dependent censoring. Estimation proceeds using a mixed U-statistic based estimating function approach. New resampling-based methods for variance estimation and model checking are also described. The methods are illustrated by application to …