Physical Sciences and Mathematics | Open Access Articles

Biological, Clinical, And Forensic Analysis Using Comprehensive Two-Dimensional Gas Chromatography, Nicholas Snow

Nicholas A Snow

No abstract provided.

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Humancentric Applications Of Rfid Chips, S. Derrick, K. Michael, H. Tootell

Dr Holly Tootell

No abstract provided.

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Topic And Role Discovery In Social Networks With Experiments On Enron And Academic Email, Andrew Mccallum, Xuerui Wang, Andrés Corrada-Emmanuel

Andrés Corrada-Emmanuel

Previous work in social network analysis (SNA) has modeled the existence of links from one entity to another, but not the attributes such as language content or topics on those links. We present the Author-Recipient-Topic (ART) model for social network analysis, which learns topic distributions based on the direction-sensitive messages sent between entities. The model builds on Latent Dirichlet Allocation (LDA) and the Author-Topic (AT) model, adding the key attribute that distribution over topics is conditioned distinctly on both the sender and recipient---steering the discovery of topics according to the relationships between people. We give results on both the Enron …

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On The Time-Resolved Optogalvanic Spectra Of Neon And Krypton, Naveed Piracha, K. Nesbett, S. Moten, P. Moeller

Naveed K. Piracha

In this work time resolved optogalvanic signals associated with transitions excited from the first metastable state of neon and krypton have been studied. These gases have similar energy state configurations and it is of significant interest to study their time resolved optogalvanic waveforms resulting from transitions belonging to the states of same quantum numbers. The experimentally observed optogalvanic signals recorded for different discharge currents have been fitted to a theoretical model to obtain parameters that determine amplitudes, instrumental time constants and decay rates of the 1s levels.

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Services Computing, Liang-Jie Zhang, Jia Zhang, Hong Cai

Jia Zhang

This book bridges the gap between Business and IT services. It describes research results in Web services and service-oriented architecture (SOA); business consulting methodology and utilities; and business process modeling, transformation, integration, and management. Major solution architectures, technologies and research methods are discussed in the lifecycle of services innovation research, including business componentization; services modeling, creation, realization, annotation, deployment, discovery, composition and delivery; service-to-service collaboration; and services monitoring, optimization, and management. The book provides readers with new research and solution methods to enable IT services and computing technology to better create and manage business services, which is the goal of …

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Plio-Quaternary Exhumation History Of The Central Nepalese Himalaya: 2. Thermo-Kinematic Model Of Thermochronometer Age Prediction Model, David Whipp Jr, Todd Ehlers, Ann Blythe, Katharine Huntington, Kip Hodges, Douglas Burbank

Ann Blythe

[1] In the Himalaya and other active convergent orogens, linear relationships between thermochronometer sample age and elevation are often used to estimate long-term exhumation rates. In these regions, high-relief topography and nonvertical exhumation pathways may invalidate such one-dimensional (1-D) interpretations and lead to significant errors. To quantify these errors, we integrate apatite fission track (AFT) ages from the central Himalaya with a 3-D coupled thermokinematic model, from which sample cooling ages are predicted using a cooling-rate-dependent algorithm. By changing the slip partitioning between faults near the Main Central thrust and the Main Frontal thrust system at the Himalayan range front, …

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Supporting Ad-Hoc Resource Sharing On The Web: A Peer-To-Peer Approach To Hypermedia Link Services, Jing Zhou, Wendy Hall, David De Roure, Vijay Dialani

Vijay Dialani

The key element to support ad-hoc resource sharing on the Web is to discover resources of interest. The hypermedia paradigm provides a way of overlaying a set of resources with additional information in the form of links to help people ﬁnd other resources. However, existing hypermedia approaches primarily develop mechanisms to enable resource sharing in a fairly static, centralized way. Recent developments in distributed computing, on the other hand, introduced peer-to-peer (P2P) computing that is notable for employing distributed resources to perform a critical function in a more dynamic and ad-hoc scenario. We investigate the feasibility and potential beneﬁts of …

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Arrays Of Interacting Nanostructures: Ferromagnetic And Superconducting Cases, Andrei Ursache

Andrei E. Ursache

No abstract provided.

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Dialogue Television: The Climate Engineers, James Fleming

James R. Fleming

The problem of global warming is getting massive public attention. This comes forty years after the first major government report outlining the problem. But there is considerable disagreement over what steps should be taken to mitigate the problem and some scientist fear that politicians are not displaying sufficient urgency. James Fleming describes the technological quick fixes proposed by some scientists and the problems they might create.

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Simulation And Analysis Of Ultrafast Laser Pulse Induced Plasma Generation In Dielectric Materials, Jeremy Gulley, Sebastian Winkler, William Dennis

Jeremy R. Gulley

Recent experiments on optical damage by ultrashort laser pulses have demonstrated that the temporal pulseshape can dramatically influence plasma generation in fused silica and sapphire. In this work a modified 3+1D nonlinear Schroedinger equation for the pulse propagation coupled to a rate equation for the plasma density in the dielectric material is used to simulate pulse propagation and plasma formation in a range of dielectric materials. We use these simulations to analyze the influence of pulse-width, pulse-shape and beam geometry on the formation of the electron plasma and hence damage in the bulk material. In particular, when possible, we simulate …

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Strategies For Research About Design: A Multidisciplinary Graduate Workshop, Mary Shaw, Susan Finger, Mark Gross, James Herbsleb

Mary Shaw

We are developing a graduate curriculum and summer workshop on design research intended to prepare graduate students to do research about the nature of design or research about a class of designs, including concepts, models, and methods for that class. We expect our workshop to advance the science of design of softwareintensive systems by creating a open community of design researchers, both in software design and in related disciplines, who are knowledgeable about design and design research methods and who are interested in advancing the field. The curriculum will create a common basis for discussion and identify core material to …

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Modification Of A Capillary For Electrophoresis By Electrostatic Self-Assembly Of An Enzyme For Selective Determination Of The Enzyme Substrate, Stephanie Hooper, Mark Anderson

Mark R. Anderson

The integration of a separation capillary for capillary electrophoresis (CE) with an on-column enzyme reaction for selective determination of the enzyme substrate is described. Enzyme immobilization is achieved by electrostatic assembly of poly(diallydimethylammonium chloride) (PDDA) followed by adsorption of a mixture of the negatively charged enzyme glucose oxidase (GOx) and anionic poly(styrenesulfonate) (PSS). The reaction of glucose with the GOx produces hydrogen peroxide which migrates the length of the capillary and is detected amperometrically at the capillary outlet. The enzyme reaction occurs during a capillary separation, allowing selective determination of the substrate in complex samples without the need for pre- …

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Review Of Kitchen Chemistry., Chrystal Bruce

Chrystal D. Bruce

This book contains many modules emphasizing truly important concepts in chemistry: intermolecular forces, structure, reactivity, solubility. The experiments offered exemplify the recurring phrase, “familiar chemistry in an unfamiliar place.”

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Bonebeds: Genesis, Analysis, And Paleobiological Significance, Raymond Rogers, Daivd Eberth, Anthony Fiorillo

Raymond Rogers

No abstract provided.

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The Diachroneity Of Alluvial-Fan Lithostratigraphy?: A Test Case From Southeastern Ebro Basin Magnetostratigraphy, Nicholas Swanson-Hysell, David Barbeau

David L Barbeau Jr

Alluvial-fan strata contain valuable proxy data for kinematic, climatic and sediment-flux phenomena associated with high-relief source regions. Proper application of this data is dependent upon acquisition of accurate high-resolution chronostratigraphic data, best achieved through magnetostratigraphy. Collection of magnetostratigraphic and other proxy data from composite alluvial-fan sections assumes the chronostratigraphic significance of lithostratigraphy. We present the first test of this assumption with new magnetostratigraphy collected from Paleogene rocks of the southeastern Ebro basin. We report five new magnetostratigraphic sections that collectively sample 850 m of alluvial-fan and associated fluvial strata. One-hundred meters of lithostratigraphic overlap between these sections reveals equivalent magnetic …

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Chess, Chance And Conspiracy, Mark Segal

Mark R Segal

Chess and chance are seemingly strange bedfellows. Luck and/or randomness have no apparent role in move selection when the game is played at the highest levels. However, when competition is at the ultimate level, that of the World Chess Championship (WCC), chess and conspiracy are not strange bedfellows, there being a long and colorful history of accusations levied between participants. One such accusation, frequently repeated, was that all the games in the 1985 WCC (Karpov vs Kasparov) were fixed and prearranged move by move. That this claim was advanced by a former World Champion, Bobby Fischer, argues that it ought …

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Self-Heating In Compost Piles Due To Biological Effects, Tim Marchant

Tim Marchant

The increase in temperature in compost piles/landfill sites due to micro-organisms undergoing exothermic reactions is modelled. A simplified model is considered in which only biological self-heating is present. The heat release rate due to biological activity is modelled by a function which is a monotonic increasing function of temperature over the range 0⩽T⩽a, whilst for T⩾a it is a monotone decreasing function of temperature. This functional dependence represents the fact that micro-organisms die or become dormant at high temperatures. The bifurcation behaviour is investigated for 1-d slab and 2-d rectangular slab geometries. In both cases there are two generic steady-state …

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The Extracellular Chaperone Clusterin Influences Amyloid Formation And Toxicity By Interacting With Pre-Fibrillar Structures, Justin Yerbury, Stephen Poon, Sarah Meehan, Brianna Thompson, Janet Kumita, Christopher Dobson, Mark Wilson

Mark R Wilson

Clusterin is an extracellular chaperone present in all disease-associated extracellular amyloid deposits, however, its roles in amyloid formation and protein deposition in vivo are poorly understood. The current study initially aimed to characterise the effects of clusterin on amyloid formation in vitro by a panel of eight protein substrates. Two of the substrates (Alzheimer's beta peptide and a PI3-SH3 domain) were then used in further experiments to examine the effects of clusterin on amyloid cytotoxicity and to probe the mechanism of clusterin action. We show that clusterin exerts potent effects on amyloid formation, the nature and extent of which vary …

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The Extracellular Chaperone Clusterin Potently Inhibits Human Lysozyme Amyloid Formation By Interacting With Prefibrillar Species, Mark Wilson, Justin Yerbury, Stephen Poon, Christopher Dobson, C V Robinson, Elise Stewart, Janet Kumita, Mireille Dumoulin, Gemma Caddy, Christine Hagan

Mark R Wilson

We have studied the effects of the extracellular molecular chaperone, clusterin, on the in vitro aggregation of mutational variants of human lysozyme, including one associated with familial amyloid disease. The aggregation of the amyloidogenic variant I56T is inhibited significantly at clusterin-to-lysozyme ratios as low as 1:80 (i.e. one clusterin molecule per 80 lysozyme molecules). Experiments indicate that under the conditions where inhibition of aggregation occurs, clusterin does not bind detectably to the native or fibrillar states, or to the monomeric transient intermediate known to be a key species in the aggregation reaction. Rather, it seems to interact with oligomeric species …

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Solitary Wave Interaction For A Higher-Order Nonlinear Schrodinger Equation, Tim Marchant

Tim Marchant

Solitary wave interaction for a higher-order version of the nonlinear Schrödinger (NLS) equation is examined. An asymptotic transformation is used to transform a higher-order NLS equation to a higher-order member of the NLS integrable hierarchy, if an algebraic relationship between the higher-order coefficients is satisfied. The transformation is used to derive the higher-order one- and two-soliton solutions; in general, the N-soliton solution can be derived. It is shown that the higher-order collision is asymptotically elastic and analytical expressions are found for the higher-order phase and coordinate shifts. Numerical simulations of the interaction of two higher-order solitary waves are also performed. …

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Well-Resolved Coherent Raman Spectra From Femtosecond Pulses, Sukhendu Nath, Diana Urbanek, Sean Kern, Mark Berg

Sean J. Kern

This paper demonstrates a method for measuring coherent anti-Stokes Raman spectra with a resolution limited only by the inherent linewidth of the sample, even when using pulses of a width (60 fs, 300 cm−1) that is between the widths needed for a pure frequency- or time-domain measurement. Data are collected as a function of both delay and frequency and used to recover a standard Raman spectrum. The resulting time/frequency detected experiment represents a bridge between standard time- and frequency-domain approaches to spectroscopy.

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Simultaneous Time And Frequency Detection In Femtosecond Coherent Raman Spectroscopy, Sukhendu Nath, Diana Urbanek, Sean Kern, Mark Berg

Sean J. Kern

The preceding paper showed that, in principle, a high-resolution coherent Raman spectrum can be recovered using femtosecond probe pulses by combined detection in both time and frequency. This measurement is possible even when the pulses are too broad in frequency for conventional frequency-domain spectroscopy and too broad in time for conventional time-domain spectroscopy. In this paper, the method is tested on experimental coherent anti-stokes Raman spectroscopy data from acetonitrile. Compared to theoretical models, experimental data are complicated by noise and incomplete knowledge of the pulse structure. Despite these complications, most of the information in the Raman spectrum is recovered from …

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Effects Of Glycosylation On The Structure And Function Of The Extracellular Chaperone Clusterin, Elise Stewart, Andrew Aquilina, Simon B Easterbrook-Smith, D Murphy-Durland, C Jacobsen, S Moestrup, Mark Wilson

Mark R Wilson

Clusterin is the first well characterized, constitutively secreted extracellular chaperone that binds to exposed regions of hydrophobicity on non-native proteins. It may help control the folding state of extracellular proteins by targeting them for receptor-mediated endocytosis and intracellular lysosomal degradation. A notable feature of secreted clusterin is its heavy glycosylation. Although carbohydrate comprises approximately 20−25% of the total mass of the mature molecule, its function is unknown. Results from the current study demonstrate that deglycosylation of human serum clusterin had little effect on its overall secondary structure content but produced a small increase in solvent-exposed hydrophobicity and enhanced the propensity …

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The Climate Engineers: Playing God To Save The Planet, James Fleming

James R. Fleming

As alarm over global warming spreads, a radical idea is gaining momentum. Forget cuts in greenhouse-gas emissions, some scientists argue. Find a technological fix. Bounce sunlight back into space by pumping reflective nanoparticles into the atmosphere. Launch mirrors into orbit around the earth. Create a “planetary thermostat.” But what sounds like science fiction is actually an old story. For more than a century, scientists, soldiers, and charlatans have hatched schemes to manipulate the weather and climate. Like them, today’s aspiring climate engineers wildly exaggerate what is possible, and they scarcely consider political, military, and ethical implications of attempting to manage …

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Synthesis Of Homoallyl Ethers Via Allylation Of Acetals And Aldehydes In Ionic Liquids, Ram Mohan, Peter Anzalone

Ram S. Mohan

The TMS triflate catalyzed allylation of acetals to yield homoallyl ethers proceeds smoothly at room temperature in ionic liquids. A one-pot method for the conversion of aldehydes to homoallyl ethers in an ionic liquid has also been developed. This methodology is attractive because it allows allylations to be carried out at room temperature. Ionic liquids offer a convenient replacement for CH₂Cl₂, the commonly used solvent for such reactions.

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Asymptotic Solitons On A Non-Zero Mean Level., Tim Marchant

Tim Marchant

The collision of solitary waves for a higher-order modified Korteweg-de Vries (mKdV) equation is examined. In particular, the collision between solitary waves with sech-type and algebraic (which only exist on a non-zero mean level) profiles is considered. An asymptotic transformation, valid if the higher-order coefficients satisfy a certain algebraic relationship, is used to transform the higher-order mKdV equation to an integrable member of the mKdV hierarchy. The transformation is used to show that the higher-order collision is asymptotically elastic and to derive the higher-order phase shifts. Numerical simulations of both elastic and inelastic collisions are performed. For the example covered …

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On The Size Of Succinct Indices, Alexander Golynski, Ankur Gupta, Roberto Grossi, Rajeev Raman, Satti Rao

Ankur Gupta

A succinct data structure occupies an amount of space that is close to the information-theoretic minimum plus an additional term. The latter is not necessarily a lower-order term and, in several cases, completely dominates the space occupancy both in theory and in practice. In this paper, we present several solutions to partially overcome this problem, introducing new techniques of independent interest that allow us to improve over previously known upper and lower bounds.

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Numerical Simulation Of Contaminant Flow In A Wool Scour Bowl., Tim Marchant

Tim Marchant

Wool scouring is the process of washing dirty wool after shearing. Our model numerically simulates contaminant movement in a wool scour bowl using the advection–dispersion equation. This is the first wool scour model to give time-dependent results and to model the transport of contaminants within a single scour bowl. Our aim is to gain a better understanding of the operating parameters that will produce efficient scouring. Investigating the effects of varying the parameters reveals simple, interesting relationships that give insight into the dynamics of a scour bowl.

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Software To Forecast The Global Burden Of Alzheimer's Disease, Ron Brookmeyer, Elizabeth Johnson, Kathryn Ziegler-Graham, H. Michael Arrighi

Ron Brookmeyer

Software was developed to forecast the global burden of Alzheimer’s disease and evaluate the potential impact of interventions that delay disease onset and progression. The output includes 50 year projections of Alzheimer's disease prevalence by stage of disease and region of the world. The methods are based on a stochastic multi-state model The software incorporates U.N. worldwide population forecasts and data from epidemiological studies on risks of Alzheimer’s disease. The user can also supply their own population projections, and modify input parameters for the model including the disease incidence rates, effects of interventions on disease onset and progression, and stages …

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Bayesian Predictive Information Criterion For The Evaluation Of Hierarchical Bayesian And Empirical Bayes Models, Tomohiro Ando

Tomohiro Ando

No abstract provided.

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Full-Text Articles in Physical Sciences and Mathematics

Biological, Clinical, And Forensic Analysis Using Comprehensive Two-Dimensional Gas Chromatography, Nicholas Snow

Nicholas A Snow

Humancentric Applications Of Rfid Chips, S. Derrick, K. Michael, H. Tootell

Dr Holly Tootell

Topic And Role Discovery In Social Networks With Experiments On Enron And Academic Email, Andrew Mccallum, Xuerui Wang, Andrés Corrada-Emmanuel

Andrés Corrada-Emmanuel

On The Time-Resolved Optogalvanic Spectra Of Neon And Krypton, Naveed Piracha, K. Nesbett, S. Moten, P. Moeller

Naveed K. Piracha

Services Computing, Liang-Jie Zhang, Jia Zhang, Hong Cai

Jia Zhang

Plio-Quaternary Exhumation History Of The Central Nepalese Himalaya: 2. Thermo-Kinematic Model Of Thermochronometer Age Prediction Model, David Whipp Jr, Todd Ehlers, Ann Blythe, Katharine Huntington, Kip Hodges, Douglas Burbank

Ann Blythe

Supporting Ad-Hoc Resource Sharing On The Web: A Peer-To-Peer Approach To Hypermedia Link Services, Jing Zhou, Wendy Hall, David De Roure, Vijay Dialani

Vijay Dialani

Arrays Of Interacting Nanostructures: Ferromagnetic And Superconducting Cases, Andrei Ursache

Andrei E. Ursache

Dialogue Television: The Climate Engineers, James Fleming

James R. Fleming

Simulation And Analysis Of Ultrafast Laser Pulse Induced Plasma Generation In Dielectric Materials, Jeremy Gulley, Sebastian Winkler, William Dennis

Jeremy R. Gulley

Strategies For Research About Design: A Multidisciplinary Graduate Workshop, Mary Shaw, Susan Finger, Mark Gross, James Herbsleb

Mary Shaw

Modification Of A Capillary For Electrophoresis By Electrostatic Self-Assembly Of An Enzyme For Selective Determination Of The Enzyme Substrate, Stephanie Hooper, Mark Anderson

Mark R. Anderson

Review Of Kitchen Chemistry., Chrystal Bruce

Chrystal D. Bruce

Bonebeds: Genesis, Analysis, And Paleobiological Significance, Raymond Rogers, Daivd Eberth, Anthony Fiorillo

Raymond Rogers

The Diachroneity Of Alluvial-Fan Lithostratigraphy?: A Test Case From Southeastern Ebro Basin Magnetostratigraphy, Nicholas Swanson-Hysell, David Barbeau

David L Barbeau Jr

Chess, Chance And Conspiracy, Mark Segal

Mark R Segal

Self-Heating In Compost Piles Due To Biological Effects, Tim Marchant

Tim Marchant

The Extracellular Chaperone Clusterin Influences Amyloid Formation And Toxicity By Interacting With Pre-Fibrillar Structures, Justin Yerbury, Stephen Poon, Sarah Meehan, Brianna Thompson, Janet Kumita, Christopher Dobson, Mark Wilson

Mark R Wilson

The Extracellular Chaperone Clusterin Potently Inhibits Human Lysozyme Amyloid Formation By Interacting With Prefibrillar Species, Mark Wilson, Justin Yerbury, Stephen Poon, Christopher Dobson, C V Robinson, Elise Stewart, Janet Kumita, Mireille Dumoulin, Gemma Caddy, Christine Hagan

Mark R Wilson

Solitary Wave Interaction For A Higher-Order Nonlinear Schrodinger Equation, Tim Marchant

Tim Marchant

Well-Resolved Coherent Raman Spectra From Femtosecond Pulses, Sukhendu Nath, Diana Urbanek, Sean Kern, Mark Berg

Sean J. Kern

Simultaneous Time And Frequency Detection In Femtosecond Coherent Raman Spectroscopy, Sukhendu Nath, Diana Urbanek, Sean Kern, Mark Berg

Sean J. Kern

Effects Of Glycosylation On The Structure And Function Of The Extracellular Chaperone Clusterin, Elise Stewart, Andrew Aquilina, Simon B Easterbrook-Smith, D Murphy-Durland, C Jacobsen, S Moestrup, Mark Wilson

Mark R Wilson

The Climate Engineers: Playing God To Save The Planet, James Fleming

James R. Fleming

Synthesis Of Homoallyl Ethers Via Allylation Of Acetals And Aldehydes In Ionic Liquids, Ram Mohan, Peter Anzalone

Ram S. Mohan

Asymptotic Solitons On A Non-Zero Mean Level., Tim Marchant

Tim Marchant

On The Size Of Succinct Indices, Alexander Golynski, Ankur Gupta, Roberto Grossi, Rajeev Raman, Satti Rao

Ankur Gupta

Numerical Simulation Of Contaminant Flow In A Wool Scour Bowl., Tim Marchant

Tim Marchant

Software To Forecast The Global Burden Of Alzheimer's Disease, Ron Brookmeyer, Elizabeth Johnson, Kathryn Ziegler-Graham, H. Michael Arrighi

Ron Brookmeyer

Bayesian Predictive Information Criterion For The Evaluation Of Hierarchical Bayesian And Empirical Bayes Models, Tomohiro Ando

Tomohiro Ando