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Drug-Eluting Stents For Coronary Artery Disease: A Review, David Martin, Fergal Boyle 2010 Technological University Dublin

Drug-Eluting Stents For Coronary Artery Disease: A Review, David Martin, Fergal Boyle

Articles

Over the past decade the introduction of drug-eluting stents (DESs) has revolutionised the treatment of coronary artery disease. However, in recent years concern has arisen over the long-term safety and efficacy of DESs due to the occurrence of late adverse clinical events such as stent thrombosis. With this concern in mind, research and development is currently centred on increasing the long-term safety and efficacy of DESs. The aim of this paper is to provide a thorough review of currently approved and promising investigational DESs. With dozens of companies involved in the development of new and innovative anti-restenotic agents, polymeric coatings ...


Quantification Of Vascular Parametric Indices Using Dynamic Contrast-Enhanced Magnetic Resonance Imaging, Areen Khaled Al.bashir 2010 Wayne State University

Quantification Of Vascular Parametric Indices Using Dynamic Contrast-Enhanced Magnetic Resonance Imaging, Areen Khaled Al.Bashir

Wayne State University Dissertations

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a non-invasive method used to evaluate the biological activity in early clinical trials of novel drugs targeting the tumor vasculature using gadolinium-DTPA (Gd) as a contrast agent. However, it has some limitations, such as reproducibility, data acquisition times, the presence of noise, extracting contrast concentration, estimating T1 relaxation and estimating pharmacokinetic parameters.

In this work, a new approach to used fixed T1(0) which provides more reproducible DCE results has been introduced. Using this new algorithm to quantify the vascular changes in DCE-MRI, a pre-clinical renal cell carcinoma (RCC) tumor model was used ...


Dna Linking Number Change Induced By Sequence-Specific Dna-Binding Proteins, Bo Chen, Yazhong Xiao, Chang Liu, Chen-zhong Li, Fenfei Leng 2010 Department of Chemistry and Biochemistry, Florida International University

Dna Linking Number Change Induced By Sequence-Specific Dna-Binding Proteins, Bo Chen, Yazhong Xiao, Chang Liu, Chen-Zhong Li, Fenfei Leng

Department of Chemistry and Biochemistry

Sequence-specific DNA-binding proteins play a key role in many fundamental biological processes, such as transcription, DNA replication and recombination. Very often, these DNA-binding proteins introduce structural changes to the target DNA-binding sites including DNA bending, twisting or untwisting and wrapping, which in many cases induce a linking number change (ΔLk) to the DNA-binding site. Due to the lack of a feasible approach, ΔLk induced by sequence-specific DNA-binding proteins has not been fully explored. In this paper we successfully constructed a series of DNA plasmids that carry many tandem copies of a DNA-binding site for one sequence-specific DNA-binding protein ...


Catalytic Strategies Of Glycoside Hydrolases, Luis Petersen 2010 Iowa State University

Catalytic Strategies Of Glycoside Hydrolases, Luis Petersen

Graduate Theses and Dissertations

Glycoside hydrolases (GHs) are enzymes that catalyze the hydrolysis of the glycosidic bond between two carbohydrate residues or a carbohydrate unit linked to a non-carbohydrate aglycon unit. Despite years of research dedicated to GHs, there are still several mechanistic details, relevant for individual GH enzymes, that remain to be investigated. In this work, a computational analysis of the detailed mechanism of several GHs is presented. QM/MM metadynamics simulations of two glycoside hydrolases, GH8 endoglucanase and GH43 β-xylosidase, give insight into the enzymatic deconstruction of the plant cell wall, and the detailed reaction mechanism of both enzymes. In addition, an ...


Protein And Oil Recoveries From Enzyme-Assisted Aqueous Extraction Of Soybeans And Sunflower Seed, Kerry Alan Campbell 2010 Iowa State University

Protein And Oil Recoveries From Enzyme-Assisted Aqueous Extraction Of Soybeans And Sunflower Seed, Kerry Alan Campbell

Graduate Theses and Dissertations

Aqueous extraction processing (AEP) of soybeans has the potential to achieve oil extraction yields comparable to hexane extraction without the environmental or safety concerns associated with hexane. The economic viability of this novel process depends upon maximizing the yield of free oil as well the development of a cost effective, high yielding method of recovering protein values in the aqueous by-product.

In order to direct strategies for yield improvement, mechanisms of AEP were studied by microscopic observation of extracted residual solids coupled with yield measurements and mathematical modeling. The nature of the oil-confining matrix varied depending on physical treatment of ...


Testing An Exergame For Effectiveness And Attractiveness, Jeffrey Ronald Sinclair, Philip Hingston, Martin Masek, Kazunori Nosaka 2010 Edith Cowan University

Testing An Exergame For Effectiveness And Attractiveness, Jeffrey Ronald Sinclair, Philip Hingston, Martin Masek, Kazunori Nosaka

ECU Publications Pre. 2011

In this paper, we report on an experimental study in which we investigated the use of feedback mechanisms in exergames. We based the study around the Dual Flow model for exergame design, using biophysical feedback to control exercise intensity, and player performance feedback to control gameplay challenge. We found good success in controlling exercise intensity to achieve an effective workout, while controlling gameplay challenge to improve enjoyment and attractiveness was problematic. We offer some possible reasons for this, suggesting the need for further investigation.


Development Of A Sorbent For Carbon Dioxide, Dursun Can Ozcan 2010 Iowa State University

Development Of A Sorbent For Carbon Dioxide, Dursun Can Ozcan

Graduate Theses and Dissertations

The reversible absorption of CO2 by CaO at high temperature is a promising method for capturing and removing CO2 from a hot gas stream. The main challenge facing the use of this method is the deterioration of CO2 absorption capacity when the method is applied over a large number of CO2 absorption/desorption cycles. Although various techniques have been proposed for improving the cyclic stability and performance of calcium based sorbents, a cost effective method is still needed for industrial applications. Therefore, two promising methods for improving the cyclic stability were selected for further investigation. One method is to optimize ...


Structures, Kinetics, And Modeling Of Glycoside Hydrolase Family 44 Endoglucanases From Clostridium Acetobutylicum And Ruminococcus Flavefaciens Fd-1, Christopher Donald Warner 2010 Iowa State University

Structures, Kinetics, And Modeling Of Glycoside Hydrolase Family 44 Endoglucanases From Clostridium Acetobutylicum And Ruminococcus Flavefaciens Fd-1, Christopher Donald Warner

Graduate Theses and Dissertations

Glycoside hydrolases (GH) are enzymes that hydrolyze glycosidic bonds between carbohydrates. Family 44 contains endo- and xylo- glucanases capable of hydrolyzing cellulose and hemicelluose. Two members produced by Clostridium acetobutylicum and Ruminococcus flavefaciens FD-1 are the subjects of characterization work in this dissertation.

The EG from Clostridium acetobutylicum was characterized both structurally and kinetically. Crystallization and x-ray diffraction to 2.2-y resolution revealed a TIM barrel-like structure with additional ψ-loop and β-sandwich folds. The EG hydrolyzes cellotetraose and larger cellooligosaccharides, as well as carboxymethylcellulose and xylan at approximately the same rates. It converts lichenan to oligosaccharides of intermediate size and ...


A Comrehensive Model Study For Flash Nanoprecipitation: Computational Fluid Dynamics, Micro- Particle Image Velocimetry, And Population Balance Modeling, Janine Chungyin Cheng 2010 Iowa State University

A Comrehensive Model Study For Flash Nanoprecipitation: Computational Fluid Dynamics, Micro- Particle Image Velocimetry, And Population Balance Modeling, Janine Chungyin Cheng

Graduate Theses and Dissertations

A model study has been conducted for Flash Nanoprecipitation(FNP)) - a novel approach to produce functional nanoparticles. A mixing study has been conducted in a custom-designed microscale multi-inlet vortex reactor (MIVR) and a scalar mixing model was validated against experimental data. A microPIV experiment was conducted to further validate the turbulent model. A population balance equation (PBE) has been proposed to model the FNP process. It was furthermore, integrated into a computational fluid dynamics (CFD) simulation of to yield conditions comparable to the real experimental settings. In coping with the complicated aggregation model in the CFD code, a new numerical ...


Acid Catalyzed Carbohydrate Degradation And Dehydration, Basak Cinlar 2010 Iowa State University

Acid Catalyzed Carbohydrate Degradation And Dehydration, Basak Cinlar

Graduate Theses and Dissertations

Facile commercial production of versatile polyfunctional compounds from biomass constitutes a great challenge for establishing a sustainable chemical industry. One such example is the production of furfural and hydroxymethyl furfural via dehydration of pentoses and hexoses. Identified as primary building blocks in polymer industry, their massive production is highly desired, yet suffers from several problems, such as feedstock availability, low product yields due to excessive side reactions and lack of an industrially feasible heterogeneous catalyst.

Organic acid functional groups incorporated onto mesoporous silica offer well defined catalytic sites beside their unique textural properties and therefore could be considered as promising ...


Cytocompatible Cross-Linking Of Electrospun Zein Fibers For The Development Of Water-Stable Tissue Engineering Scaffolds, Quiran Jiang, Narendra Reddy, Yiqi Yang 2010 University of Nebraska–Lincoln

Cytocompatible Cross-Linking Of Electrospun Zein Fibers For The Development Of Water-Stable Tissue Engineering Scaffolds, Quiran Jiang, Narendra Reddy, Yiqi Yang

Biological Systems Engineering: Papers and Publications

This paper reports a new method of cross-linking electrospun zein fibers using citric acid as a non-toxic cross-linker to enhance the water stability and cytocompatibility of zein fibers for tissue engineering and other medical applications. The electrospun structure has many advantages over other types of structures and protein-based biomaterials possess unique properties preferred for tissue engineering and other medical applications. However, ultrafine fiber matrices developed from proteins have poor mechanical properties and morphological stability in the aqueous environments required for medical applications. Efforts have been made to improve the water stability of electrospun protein scaffolds using cross-linking and other approaches ...


Testing Fuel Efficiency Of A Tractor With A Continuously Variable Transmission, Bart A. Coffman, Michael F. Kocher, Viacheslav I. Adamchuk, Roger M. Hoy, Erin E. Blankenship 2010 University of Nebraska-Lincoln

Testing Fuel Efficiency Of A Tractor With A Continuously Variable Transmission, Bart A. Coffman, Michael F. Kocher, Viacheslav I. Adamchuk, Roger M. Hoy, Erin E. Blankenship

Biological Systems Engineering: Papers and Publications

A John Deere 8530 IVT tractor (Waterloo, Iowa) with a continuously variable transmission (CVT) that could be operated in automatic (CVT) or manual (fixed gear ratio) mode was tested for fuel consumption at a setpoint travel speed of 9 km·h‐1 with 17 different drawbar loads. Linear regression analysis results showed that with the throttle set to maximum in both transmission modes, operating the tractor with the transmission in the automatic mode was more fuel efficient than operating with the transmission in the manual mode when the drawbar power was approximately 78%, or less, of maximum power. When load ...


Integration Mechanisms For Heading Perception, Elif M. Sikoglu, Finnegan J. Calabro, Scott A. Beardsley, Lucia M. Vaina 2010 Boston University

Integration Mechanisms For Heading Perception, Elif M. Sikoglu, Finnegan J. Calabro, Scott A. Beardsley, Lucia M. Vaina

Biomedical Engineering Faculty Research and Publications

Previous studies of heading perception suggest that human observers employ spatiotemporal pooling to accommodate noise in optic flow stimuli. Here, we investigated how spatial and temporal integration mechanisms are used for judgments of heading through a psychophysical experiment involving three different types of noise. Furthermore, we developed two ideal observer models to study the components of the spatial information used by observers when performing the heading task. In the psychophysical experiment, we applied three types of direction noise to optic flow stimuli to differentiate the involvement of spatial and temporal integration mechanisms. The results indicate that temporal integration mechanisms play ...


The Effect Of Abductor Muscle And Anterior-Posterior Hip Contact Load Simulation On The In-Vitro Primary Stability Of A Cementless Hip Stem, Youngbae Park, Carolyne Albert, Yong-San Yoon, Göran Fernlund, Hanspeter Frei, Thomas R. Oxland 2010 Korean Advanced Institute of Science and Technology

The Effect Of Abductor Muscle And Anterior-Posterior Hip Contact Load Simulation On The In-Vitro Primary Stability Of A Cementless Hip Stem, Youngbae Park, Carolyne Albert, Yong-San Yoon, Göran Fernlund, Hanspeter Frei, Thomas R. Oxland

Biomedical Engineering Faculty Research and Publications

Background

In-vitro mechanical tests are commonly performed to assess pre-clinically the effect of implant design on the stability of hip endoprostheses. There is no standard protocol for these tests, and the forces applied vary between studies. This study examines the effect of the abductor force with and without application of the anterior-posterior hip contact force in the in-vitro assessment of cementless hip implant stability.

Methods

Cementless stems (VerSys Fiber Metal) were implanted in twelve composite femurs which were divided into two groups: group 1 (N = 6) was loaded with the hip contact force only, whereas group 2 (N = 6) was ...


Net Radiation Dynamics: Performance Of 20 Daily Net Radiation Models As Related To Model Structure And Intricacy In Two Climates, Suat Irmak, Denis Mutiibwa, José O. Payero 2010 University of Nebraska-Lincoln

Net Radiation Dynamics: Performance Of 20 Daily Net Radiation Models As Related To Model Structure And Intricacy In Two Climates, Suat Irmak, Denis Mutiibwa, José O. Payero

Biological Systems Engineering: Papers and Publications

We compared daily net radiation (Rn) estimates from 19 methods with the ASCE‐EWRI Rn estimates in two climates: Clay Center, Nebraska (sub‐humid) and Davis, California (semi‐arid) for the calendar year. The performances of all 20 methods, including the ASCE‐EWRI Rn method, were then evaluated against Rn data measured over a non‐stressed maize canopy during two growing seasons in 2005 and 2006 at Clay Center. Methods differ in terms of inputs, structure, and equation intricacy. Most methods differ in estimating the cloudiness factor, emissivity (α), and calculating net longwave radiation (Rnl ...


Sodium Hydroxide Pretreatment And Enzymatic Hydrolysis Of Coastal Bermuda Grass, Ziyu Wang, Deepak R. Keshwani, Arthur P. Redding, Jay J. Cheng 2010 North Carolina State University

Sodium Hydroxide Pretreatment And Enzymatic Hydrolysis Of Coastal Bermuda Grass, Ziyu Wang, Deepak R. Keshwani, Arthur P. Redding, Jay J. Cheng

Biological Systems Engineering: Papers and Publications

Coastal Bermuda grass was pretreated with NaOH at concentrations from 0.5% to 3% (w/v) for a residence time from 15 to 90 min at 121 °C. The pretreatments were evaluated based on total lignin removal and production of total reducing sugars, glucose and xylose from enzymatic hydrolysis of the pretreated biomass. Up to 86% lignin removal was observed. The optimal NaOH pretreatment conditions at 121 °C for total reducing sugars production as well as glucose and xylose yields are 15 min and 0.75% NaOH. Under these optimal pretreatment conditions, total reducing sugars yield was about 71% of ...


Testing Of Rtk-Level Satellite-Based Tractor Auto-Guidance Using A Visual Sensor System, Dwight Easterly, Viacheslav I. Adamchuk, Roger M. Hoy, Michael F. Kocher 2010 University of Nebraska-Lincoln

Testing Of Rtk-Level Satellite-Based Tractor Auto-Guidance Using A Visual Sensor System, Dwight Easterly, Viacheslav I. Adamchuk, Roger M. Hoy, Michael F. Kocher

Biological Systems Engineering: Papers and Publications

The use of satellite-based positioning has advanced considerably in the world of agriculture, providing a range of technical solutions that include the automated steering of tractors and self-propelled machinery. With the development of auto-guidance systems comes the need to evaluate their performance. Given that current precision and accuracy claims are relatively small in magnitude, it is imperative there be a testing system capable of detecting errors with ten times greater accuracy-- possibly as little as a few millimeters. A visual sensor was adopted to achieve this level of measurement resolution. The sensor was used to determine the cross-track error estimates ...


Dual-Stage Sugar Substitution In Strawberries With A Stevia-Based Sweetener, Juan Garcia-Noguera, Curtis L. Weller, Francisca I. P. Oliveira, Sueli Rodrigues, Fabiano A. N. Fernandes 2010 University of Nebraska-Lincoln

Dual-Stage Sugar Substitution In Strawberries With A Stevia-Based Sweetener, Juan Garcia-Noguera, Curtis L. Weller, Francisca I. P. Oliveira, Sueli Rodrigues, Fabiano A. N. Fernandes

Biological Systems Engineering: Papers and Publications

The present study introduces and analyzes a new process denominated dual-stage sugar substitution (D3S). This process aims to induce sugar substitution in strawberries. In a first stage, high-calorie sugars (sucrose, fructose and glucose) are partially removed from the fruit samples and in a second stage, low-calorie sugar (stevioside and rebaudioside) is incorporated to the fruit to maintain its sweetness. The process was evaluated by studying the use of ultrasound application in one or both stages of the D3S process. Best performance of the process was obtained by subjecting the fruit samples to ultrasound in the sugar removal stage followed by ...


Ultrasound-Assisted Osmotic Dehydration Of Strawberries: Effect Of Pretreatment Time And Ultrasonic Frequency, Juan Garcia-Noguera, Francisca I. P. Oliveira, Maria Izabel Gallão, Curtis L. Weller, Sueli Rodrigues, Fabiano A. N. Fernandes 2010 University of Nebraska-Lincoln

Ultrasound-Assisted Osmotic Dehydration Of Strawberries: Effect Of Pretreatment Time And Ultrasonic Frequency, Juan Garcia-Noguera, Francisca I. P. Oliveira, Maria Izabel Gallão, Curtis L. Weller, Sueli Rodrigues, Fabiano A. N. Fernandes

Biological Systems Engineering: Papers and Publications

Pretreatment of fruits prior to drying has shown success in reducing drying time and costs. In this work, ultrasound-assisted osmotic dehydration has been implemented as a method to increase water diffusivity and reduce drying time in strawberries. Strawberry halves were immersed in distilled water and in two different concentrations of sucrose solutions while pretreatment time and ultrasonic frequency levels were varied to determine their effect on drying time, water loss, and soluble solids gain. A microscopic analysis was carried out to evaluate the formation of microchannels and other changes to the fruit tissue structure. Greater sucrose concentration used in ultrasound- ...


Microwave-Based Alkali Pretreatment Of Switchgrass And Coastal Bermudagrass For Bioethanol Production, Deepak R. Keshwani, Jay J. Cheng 2010 University of Nebraska-Lincoln

Microwave-Based Alkali Pretreatment Of Switchgrass And Coastal Bermudagrass For Bioethanol Production, Deepak R. Keshwani, Jay J. Cheng

Biological Systems Engineering: Papers and Publications

Switchgrass and coastal bermudagrass are promising lignocellulosic feedstocks for bioethanol production. However, pretreatment of lignocelluloses is required to improve production of fermentable sugars from enzymatic hydrolysis. Microwave- based alkali pretreatment of switchgrass and coastal bermudagrass was investigated in this study. Pretreatments were carried out by immersing the biomass in dilute alkali reagents and exposing the slurry to microwave radiation at 250 W for residence times ranging from 5 to 20 min. Simons’ stain method was used to quantify changes in biomass porosity as a result of the pretreatment. Pretreatments were evaluated based on yields of total reducing sugars, glucose, and ...


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