Engineering Commons^™

Improved Formulation Of A Recombinant Ricin A-Chain Vaccine Iincreases Its Stability And Effective Antigenicity, John H. Carra, Robert W. Wannemacher, Ralph F. Tammariello, Changhong Y. Lindsey, Richard E. Dinterman, Rowena D. Schokman, Leonard A. Smith

United States Army: Publications

Ricin is a potent toxin associated with bioterrorism for which no vaccine or specific countermeasures are currently available. A stable, non-toxic and immunogenic recombinant ricin A-chain vaccine (RTA 1-33/44-198) has been developed by protein engineering. We identified optimal formulation conditions for this vaccine under which it remained stable and potent in storage for up to 18 months, and resisted multiple rounds of freeze–thawing without stabilizing co-solvents. Reformulation from phosphate buffer to succinate buffer increased adherence of the protein to aluminum hydroxide adjuvant from 15 to 91%, with a concomitant increase of nearly threefold in effective antigenicity in a mouse model. …

A Refined Pharmacophore Identifies Potent 4-Amino-7-Chloroquinoline-Based Inhibitors Of The Botulinum Neurotoxin Serotype A Metalloprotease, James C. Burnett, Dejan Opsenica, Kamaraj Sriraghavan, Rekha G. Panchal, Gordon Ruthel, Ann R. Hermone, Tam L. Nguyen, Tara A. Kenny, Douglas J. Lane, Connor F. Mcgrath, James J. Schmidt, Jonathan L. Vennerstrom, Rick Gussio, Bogdan A. Solaja, Sina Bavari

United States Army: Publications

We previously identified structurally diverse small molecule (non-peptidic) inhibitors (SMNPIs) of the botulinum neurotoxin serotype A (BoNT/A) light chain (LC). Of these, several (including antimalarial drugs) contained a 4-amino-7-chloroquinoline (ACQ) substructure and a separate positive ionizable amine component. The same antimalarials have also been found to interfere with BoNT/A translocation into neurons, via pH elevation of the toxin-mediated endosome. Thus, this structural class of small molecules may serve as dual-function BoNT/A inhibitors. In this study, we used a refined pharmacophore for BoNT/A LC inhibition to identify four new, potent inhibitors of this structural class (IC50’s ranged from 3.2 to 17 …

Phase I Dose Escalation Safety And Immunogenicity Trial Of Plasmodium Falciparum Apical Membrane Protein (Ama-1) Fmp2.1, Adjuvanted With As02a, In Malaria-Naive Adults At The Walter Reed Army Institute Of Research, Mark E. Polhemus, Alan J. Magill, James F. Cummings, Kent E. Kester, Chris F. Ockenhouse, David E. Lanar, Sheetij Dutta, Arnoldo Barbosa, Lorraine Soisson, Carter L. Diggs, Sally A. Robinson, John D. Haynes, V. Ann Stewart, Lisa A. Ware, Clara Brando, Urszula Krzych, Robert A. Bowden, Joe D. Cohen, Marie-Claude Dubois, Opokua Ofori-Anyinam, Els De-Kock, W. Ripley Ballou, D. Gray Heppner Jr.

United States Army: Publications

We report the first safety and immunogenicity trial of the Plasmodium falciparum vaccine candidate FMP2.1/AS02A, a recombinant E. coli-expressed protein based upon the apical membrane antigen-1 (AMA-1) of the 3D7 clone formulated with the AS02A adjuvant. We conducted an open-label, staggered-start, dose-escalating Phase I trial in 23 malaria-naıve volunteers who received 8, 20 or 40 _g of FMP2.1 in a fixed volume of 0.5mL of AS02A on a 0, 1, and 2 month schedule. Nineteen of 23 volunteers received all three scheduled immunizations. The most frequent solicited local and systemic adverse events associated with immunization were injection site pain (68%) …

An In Vitro Comparative Study On The Reactivation Of Nerve Agent-Inhibited Guinea Pig And Human Acetylcholinesterases By Oximes, Chunyuan Luo, Min Tong, Nageswararao Chilukuri, Karen Brecht, Donald M. Maxwell, Ashima Saxena

United States Army: Publications

The reactivation of nerve agent-inhibited acetylcholinesterase (AChE) by oxime is the most important step in the treatment of nerve agent poisoning. Since the evaluation of nerve agent antidotes cannot be conducted in humans, results from animal experiments are extrapolated to humans. Guinea pig is one of the animal models that is frequently used for conducting nerve agent antidote evaluations. Several investigations have demonstrated that the efficacy of an oxime primarily depends on its ability to reactivate nerve agent-inhibited AChE. If the in Vitro oxime reactivation of nerve agent-inhibited animal AChE is similar to that of human AChE, it is likely …

United States Air Force Posture Statement 2007, U.S. Air Force

United States Air Force: Publications

Our 2007 Posture Statement articulates the major elements required to fulfill our mission. It reaffirms our commitment to focus our energies on the Global War on Terror; to develop and care for our Airmen and their families; and to recapitalize and modernize our aging aircraft, spacecraft and equipment.

The Complete Management Of Extremity Vascular Injury In A Local Population: A Wartime Report From The 332nd Expeditionary Medical Group/Air Force Theater Hospital, Balad Air Base, Iraq, Michael A. Peck, W. Darrin Clouse, Mitchell W. Cox, Andrew N. Bowser, Jonathan L. Eliason, Donald H. Jenkins, David L. Smith, Todd E. Rasmussen

United States Air Force: Publications

Background: Although the management of vascular injury in coalition forces during Operation Iraqi Freedom has been described, there are no reports on the in-theater treatment of wartime vascular injury in the local population. This study reports the complete management of extremity vascular injury in a local wartime population and illustrates the unique aspects of this cohort and management strategy.

Methods: From September 1, 2004, to August 31, 2006, all vascular injuries treated at the Air Force Theater Hospital (AFTH) in Balad, Iraq, were registered. Those in non-coalition troops were identified and retrospectively reviewed.

Results: During the study …

Impact Of Phlebotomine Sand Flies On U.S. Military Operations At Tallil Air Base, Iraq: 3. Evaluation Of Surveillance Devices For The Collection Of Adult Sand Flies, Douglas A. Burkett, Ronald Knight, James A. Dennett, Van Sherwood, Edgar Rowton, Russell E. Coleman

United States Air Force: Publications

We evaluated the effectiveness of commercially available light traps and sticky traps baited with chemical light sticks for the collection of phlebotomine sand flies. Evaluations were conducted at Tallil Air Base, Iraq, in 2003. In an initial study, a Centers for Disease Control and Prevention (CDC)-style trap with UV bulb collected significantly more sand flies than did an up-draft CDC trap, a standard down-draft CDC trap (STD-CDC), or a sticky strap with a green chemical light stick. In a subsequent study, we found that the addition of chemical light sticks to sticky traps resulted in a significant increase in the …

Improved Hole-Injection Contact For Top-Emitting Polymeric Diodes, Juo-Hao Li, Jinsong Huang, Yang Yang

Department of Mechanical and Materials Engineering: Faculty Publications

In this letter, an efficient hole-injection contact was achieved for the top-emitting polymeric light-emitting diodes (PLEDs). The anode has a structure of metal/molybdenum oxide/ poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS). It has been found that hole injection was significantly improved by inserting a thin layer of MoO₃ between aluminum and PEDOT:PSS. An ultraviolet photoelectron spectroscopy (UPS) was used to investigate the change of work function, and photovoltaic measurement confirmed that the improved hole injection is due to the reduction of barrier height, resulted from the addition of transition metal oxide. PEDOT:PSS layer was found necessary in anode structure to further enhance the …

A Novel Processing Route For The Production Of Nanoparticulate Zinc Oxide, Declan Mccormack, Grainne Duffy, Suresh Pillai

Articles

Zinc oxide nanoparticles have been processed from a novel isophthalate
precursor. In contrast to those processed from an oxalate precursor, this
material exhibits three-dimensional, non-directional aggregation behaviour.
Such non-directional aggregation of uniaxial crystallites may allow for the
production of structures with a higher proportion of catalytically active
surfaces than can be prepared through conventional sol–gel methods. XRD,
FTIR, TEM and SEM were used to characterize the synthesized materials.
Zinc oxide particles synthesized by using isophthalic acid
(C6H4-1,3-(COOH)2) are found to be slightly smaller than the previously
reported materials prepared through chelation with oxalic acid
(H2C2O2·2H2O).

Ferroelectric Properties Of Langmuir-Blodgett Copolymer Films At The Nanoscale, A. Tolstousov, R. V. Gaynutdinov, R. Tadros-Morgane, Herbert Kliem, Stephen Ducharme, Vladimir M. Fridkin

Stephen Ducharme Publications

Langmuir-Blodgett (LB) films are well known structures prepared as a result of successive transfer of monolayers (ML) from the gas-liquid interface onto solid substrates. One impressive possibility of LB method is the opportunity to vary the thickness of the film to an accuracy of one transfer, which could coincide with one ML. The ferroelectric properties of a copolymer of vinylidene fluoride and trifluorethylene P[VDF-TrFE] prepared by LB deposition are investigated in the region of a few monolayers.

Oxygenated Interface On Biomass Burn Tar Balls Determined By Single Particle Scanning Transmission X-Ray Microscopy, Alexei V. Tivanski, Rebecca J. Hopkins, Tolek Tyliszczak, Mary K. Gilles

United States Department of Energy: Publications

Carbonaceous particles originating from biomass burning can account for a large fraction of organic aerosols in a local environment. Presently, their composition, physical and chemical properties, as well as their environmental effects are largely unknown. Tar balls, a distinct type of highly spherical carbonaceous biomass burn particles, have been observed in a number of field campaigns. The Yosemite Aerosol Characterization Study that took place in summer 2002 occurred during an active fire season in the western United States; tar balls collected during this field campaign are described in this article. Scanning transmission X-ray microscopy and near-edge X-ray absorption fine structure …

Controlled Covalent Functionalization Of Multiwalled Carbon Nanotubes Using [4 + 2] Cycloaddition Of Benzocyclobutenes, Georgios Sakellariou, Haining Ji, Jimmy W. Mays, Nikos Hadjichristidis, Durairaj Baskaran

United States Department of Energy: Publications

Surface modification of carbon nanotubes (CNTs) through covalent functionalization is vital for the development of high-performance composite materials, chemosensors, nanoelectronics, photovoltaic devices, as well as for a range of biomedical applications. Several methods have been developed to functionalize CNTs. The introduction of acid groups by acid digestion disrupts the structural integrity of CNTs. Apart from shortening the tubes, oxidatively generated acid groups are inhomogenously located at the tips of broken CNTs and, hence, functionalization using acid groups as precursors does not give a statistical distribution of functional groups throughout the surface of the CNTs.

Controlled Covalent Functionalization Of Multiwalled Carbon Nanotubes Using [4 + 2] Cycloaddition Of Benzocyclobutenes, Georgios Sakellariou, Haining Ji, Jimmy W. Mays, Nikos Hadjichristidis, Durairaj Baskaran

United States Department of Energy: Publications

Surface modification of carbon nanotubes (CNTs) through covalent functionalization is vital for the development of high-performance composite materials, chemosensors, nanoelectronics, photovoltaic devices, as well as for a range of biomedical applications. Several methods have been developed to functionalize CNTs. The introduction of acid groups by acid digestion disrupts the structural integrity of CNTs. Apart from shortening the tubes, oxidatively generated acid groups are inhomogenously located at the tips of broken CNTs and, hence, functionalization using acid groups as precursors does not give a statistical distribution of functional groups throughout the surface of the CNTs.

Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry Characterization Of Primary Amine End-Functionalized Polystyrene And Poly(Methyl Methacrylate) Synthesized By Living Anionic Polymerization Techniques, Haining Ji, Georgios Sakellariou, Jimmy W. Mays

United States Department of Energy: Publications

The reaction of living anionic polymers with 2,2,5,5-tetramethyl-1-(3-bromopropyl)-1-aza-2,5- disilacyclopentane (1) was investigated using coupled thin layer chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Structures of byproducts as well as the major product were determined. The anionic initiator having a protected primary amine functional group, 2,2,5,5-tetramethyl- 1-(3-lithiopropyl)-1-aza-2,5-disilacyclopentane (2), was synthesized using all-glass high-vacuum techniques, which allows the long-term stability of this initiator to be maintained. The use of 2 in the preparation of well-defined aliphatic primary amine R-end-functionalized polystyrene and poly(methyl methacrylate) was investigated. Primary amino R-end-functionalized poly(methyl methacrylate) can be obtained near-quantitatively by reacting 2 with 1,1-diphenylethylene in tetrahydrofuran …

Peridynamic States And Constitutive Modeling, S. A. Silling, M. Epton, O. Weckner, J. Xu, E. Askari

United States Department of Energy: Publications

A generalization of the original peridynamic framework for solid mechanics is proposed. This generalization permits the response of a material at a point to depend collectively on the deformation of all bonds connected to the point. This extends the types of material response that can be reproduced by peridynamic theory to include an explicit dependence on such collectively determined quantities as volume change or shear angle. To accomplish this generalization, a mathematical object called a deformation state is defined, a function that maps any bond onto its image under the deformation. A similar object called a force state is defined, …

Efficiency Of Gene Silencing In Arabidopsis: Direct Inverted Repeats Vs. Transitive Rnai Vectors, Sergei A. Filichkin, Stephen P. Difazio, Amy M. Brunner, John M. Davis, Zamin K. Yang, Udaya C. Kalluri, Renee S. Arias, Elizabeth Etherington, Gerald A. Tuskan, Steven H. Strauss

United States Department of Energy: Publications

We investigated the efficiency of RNA interference (RNAi) in Arabidopsis using transitive and homologous inverted repeat (hIR) vectors. hIR constructs carry self-complementary intron-spliced fragments of the target gene whereas transitive vectors have the target sequence fragment adjacent to an intron-spliced, inverted repeat of heterologous origin. Both transitive and hIR constructs facilitated specific and heritable silencing in the three genes studied (AP1 , ETTIN and TTG1 ). Both types of vectors produced a phenotypic series that phenocopied reduction of function mutants for the respective target gene. The hIR yielded up to fourfold higher proportions of events with strongly manifested reduction …

Phosphate Imposed Limitations On Biological Reduction And Alteration Of Ferrihydrite, Thomas Borch, Yoko Masue, Ravi K. Kukkadapu, Scott Fendorf

United States Department of Energy: Publications

Biogeochemical transformation (inclusive of dissolution) of iron (hydr)oxides resulting from dissimilatory reduction has a pronounced impact on the fate and transport of nutrients and contaminants in subsurface environments. Despite the reactivity noted for pristine (unreacted) minerals, iron (hydr)oxides within native environments will likely have a different reactivity owing in part to changes in surface composition. Accordingly, here we explore the impact of surface modifications induced by phosphate adsorption on ferrihydrite reduction by Shewanella putrefaciens under static and advective flow conditions. Alterations in surface reactivity induced by phosphate changes the extent, decreasing Fe(III) reduction nearly linearly with increasing P surface coverage, …

Reduction Of Pertechnetate [Tc(Vii)] By Aqueous Fe(Ii) And The Nature Of Solid Phase Redox Products, John M. Zachara, Steve M. Heald, Byong-Hun Jeon, Ravi K. Kukkadapu, Chongxuan Liu, James P. Mckinley, Alice C. Dohnalkova, Dean A. Moore

United States Department of Energy: Publications

The subsurface behaviour of ⁹⁹Tc, a contaminant resulting from nuclear fuels reprocessing, is dependent on its valence (e.g., IV or VII). Abiotic reduction of soluble Tc(VII) by Fe(II)_(aq) in pH 6–8 solutions was investigated under strictly anoxic conditions using an oxygen trap (<7.5 · 10^-9 atm O₂). The reduction kinetics were strongly pH dependent. Complete and rapid reduction of Tc(VII) to a precipitated Fe/Tc(IV) form was observed when 11 µmol/L of Tc(VII) was reacted with 0.4 mmol/L Fe(II) at pH 7.0 and 8.0, while no significant reduction was observed over 1 month at pH 6.0. Experiments conducted …

Biostimulation Of Iron Reduction And Subsequent Oxidation Of Sediment Containing Fe-Silicates And Fe-Oxides: Effect Of Redox Cycling On Fe(Iii) Bioreduction, John Komlos, Ravi K. Kukkadapu, John M. Zachara, Peter R. Jaffe

United States Department of Energy: Publications

Sediment containing a mixture of iron (Fe)-phases, including Fe-oxides (mostly Al-goethite) and Fe-silicates (illites and vermiculite) was bioreduced in a long-term flow through column experiment followed by re-oxidation with dissolved oxygen. The objective of this study was (a) to determine the nature of the re-oxidized Fe(III), and (b) to determine how redox cycling of Fe would affect subsequent Fe(III)-bioavailability. In addition, the effect of Mn on Fe(III) reduction was explored.⁵⁷Fe-Mössbauer spectroscopy measurements showed that biostimulation resulted in partial reduction (20%) of silicate Fe(III) to silicate Fe(II) while the reduction of goethite was negligible. Furthermore, the reduction of Fe …

Influence Of Calcium On Microbial Reduction Of Solid Phase Uranium(Vi), Chongxuan Liu, Byong-Hun Jeon, John M. Zachara, Zheming Wang

United States Department of Energy: Publications

The effect of calcium on the dissolution and microbial reduction of a representative solid phase uranyl [U(VI)], sodium boltwoodite (NaUO₂SiO₃OH •1.5H₂O), was investigated to evaluate the rate-limiting step of microbial reduction of the solid phase U(VI). Microbial reduction experiments were performed in a culture of a dissimilatory metal-reducing bacterium (DMRB), Shewanella oneidensis strain MR-1, in a bicarbonate medium with lactate as electron donor at pH 6.8 buffered with PIPES. Calcium increased the rate of Na-boltwoodite dissolution and U(VI) bioavailability by increasing its solubility through the formation of a ternary aqueous calcium-uranyl-carbonate species. The ternary …

Spectroscopic Evidence For Uranium Bearing Precipitates In Vadose Zone Sediments At The Hanford 300-Area Site, Yuji Arai, M. A. Marcus, N. Tamura, J. A. Davis, John M. Zachara

United States Department of Energy: Publications

Uranium (U) solid-state speciation in vadose zone sediments collected beneath the former North Process Pond (NPP) in the 300 Area of the Hanford site (Washington) was investigated using multi-scale techniques. In 30 day batch experiments, only a small fraction of total U (~7.4%) was released to artificial groundwater solutions equilibrated with1% pCO₂. Synchrotron-based micro-X-ray fluorescence spectroscopy analyses showed that U was distributed among at least two types of species: (i) U discrete grains associated with Cu and (ii) areas with intermediate U concentrations on grains and grain coatings. Metatorbernite (Cu[UO₂]₂[PO₄]₂•8H …

Cation Exchange Reactions Controlling Desorption Of 90sr2+ From Coarse-Grained Contaminated Sediments At The Hanford Site, Washington, James Mckinley, John M. Zachara, Steven Smith, Chongxuan Liu

United States Department of Energy: Publications

Nuclear waste that bore ⁹⁰Sr²⁺ was accidentally leaked into the vadose zone at the Hanford site, and was immobilized at relatively shallow depths in sediments containing little apparent clay or silt-sized components. Sr²⁺, ⁹⁰Sr²⁺, Mg2+, and Ca²⁺ was desorbed and total inorganic carbon concentration was monitored during the equilibration of this sediment with varying concentrations of Na⁺, Ca²⁺. A cation exchange model previously developed for similar sediments was applied to these results as a predictor of final solution compositions. The model included binary exchange reactions for the four …

Geochemical Processes Controlling Migration Of Tank Wastes In Hanford’S Vadose Zone, John M. Zachara, Jeff Serne, Mark Freshley, Fred Mann, Frank Anderson, Marcus Wood, Tom Jones, Dave Myers

United States Department of Energy: Publications

Nuclear wastes from Hanford’s processing for separation of plutonium are stored in massive, buried, single-shell tanks in 18 tank farms. These so-called tank wastes were initially thermally hot because of radioactive decay, and many exhibited extreme chemical character in terms of pH, salinity, and radionuclide concentration. At present, 67 of the 149 single shell tanks are suspected to have released over 1.9 million L of tank waste to the vadose zone, with most leak events occurring between 1950 and 1975. Boreholes have been placed through the largest vadose zone plumes to define the extent of contaminant migration and to develop …

Generation Of Electron Bunches At Low Repetition Rates Using A Beat-Frequency Technique, M. Poelker, J. Grames, J. Hansknecht, R. Kazimi, J. Musson

United States Department of Energy: Publications

Even at a continuous wave facility such as CEBAF at Jefferson Lab, an electron beam with long time intervals (tens of ns) between individual bunches can be useful, for example, to isolate sources of background via time of flight detection or to measure the energy of neutral particles that cannot be separated with a magnetic field. This paper describes a demonstrated method to quickly and easily deliver bunches with repetition rates of 20 to 100 MHz corresponding to time intervals between 50 and 10 ns (respectively). This is accomplished by changing the ON/OFF frequency of the photogun drive laser by …

Small Wind Electric Systems: A Nebraska Consumer’S Guide

United States Department of Energy: Publications

Can I use wind energy to power my home? This question is being asked across the country as more people look for affordable and reliable sources of electricity. Small wind electric systems can make a significant contribution to our nation’s energy needs. Although wind turbines large enough to provide a significant portion of the electricity needed by the average U.S. home generally require one acre of property or more, approximately 21 million U.S. homes are built on one-acre and larger sites, and 24% of the U.S. population lives in rural areas.

A small wind electric system will work for you …

Valuing Water Quality Improvements In The United States Using Meta-Analysis: Is The Glass Half-Full Or Half-Empty For National Policy Analysis?, George Van Houtven, John Powers, Subhrendu K. Pattanayak

United States Environmental Protection Agency: Publications

The literature estimating the economic value for water quality changes has grown considerably over the last 30 years, resulting in an expanded pool of information potentially available to support national and regional policy analysis. Using 131 willingness to pay estimates from 18 studies that use a similar definition of water quality, we performed a meta-regression analysis and found mixed results. We find that WTP varies in systematic and expected ways with respect to factors such as the size of the water quality changes, average household income, and use/nonuse characteristics of respondents. As a whole, we conclude that our metaregression results …

Nebraska Summary: S589 Agco Rt165a, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Dynamic Impact Testing Of W152x13.4 (W6x9) Steel Posts On A 2:1 Slope, Gopi Dey, Ronald K. Faller, John A. Hascall, Robert W. Bielenberg, Karla A. Polivka, Kirk Molacek

Mid-America Transportation Center: Final Reports and Technical Briefs

Dynamic impact testing of W152x13.4 (W6x9) steel posts at various embedment depths has been detailed, and the results stated. A total of 17 bogie tests have been performed on a 2:1 slope, with post lengths varying from 1,829 mm (6 ft) through 2,743 mm (9 ft). A total of four bogie tests were performed on level terrain using 1,829-mm (6-ft) long steel posts at two different impact speeds. For each bogie test, raw acceleration data, obtained from accelerometers, was filtered and then force-displacement and energy-displacement graphs were plotted. From the energy-displacement graphs, the average post-soil forces were calculated for a …

Analysis And Prediction Of Effectiveness For Residential Hvac Ductwork, Jinson J. Erinjeri

Doctoral Dissertations

An analysis of residential HVAC ductwork has been performed. Ductwork in 55 homes in Northern Louisiana was tested to determine duct leakage by means of using various measurement techniques to determine the differences between the existing methods as well as the revised method developed in this project referred to as Generalized Subtraction Correction Algorithm (GSCA). A protocol to measure and estimate return leaks at operating pressure was developed. The weighted average return leakage for the homes sampled was determined to be 115 cfm at operating pressure whereas the weighted average duct leakage was determined to be 348 cfm at 25 …

Chitosan Paste From Crawfish Shells As A Synthetic Bone Graft Material: Preparation, Characterization And Animal Study, Jerome G. Saltarrelli Jr.

Doctoral Dissertations

Bone loss associated with musculoskeletal trauma or metabolic diseases often requires bone grafts. Autograft or allograft bones are limited in supply. Therefore, development of synthetic bone graft materials is an active area of research. For several years the biomaterials group at LSUHSC-Shreveport has been investigating the use of chitosan purified from crawfish shells using a process patented by my research advisor, Dr. Debi Mukherjee.

Chitin is a polysaccharide that exists in fungi, exoskeleton of insects and outer shell of crustaceans. It is biocompatible, osteoconductive, antimicrobial, biodegradable, non-toxic, haemostatic, fungicidal, and the second most abundant natural polysaccharide on earth. Removal of …