bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of the distributed activation energy model to biomass and biomass constituents devolatilization
Authors: Navarro María V. , Murillo Ramón , Mastral Ana M. , Puy Neus , Bartroli Jordi
Published: July 2009

In this study, an investigation about the thermal behavior of four different woods was carried out. The distributed activation energy model was applied to study the effect of heating rate on the reaction of single solids. Results obtained were used in the curve prediction of fraction of mass remaining and rate of mass loss vs. temperature at more realistic heating rates. The possible calculation of biomass samples behavior in pyrolysis conditions as the summation of their constituents, lignin, cellulose, and hemi‐cellulose is also explored. All the samples show a weak interaction between the constituents which produce slight differences between experimental and calculated behavior. However, differences between experimental and calculated data lower than 2% offer a robust test of the applicability of the model on kinetic studies of a wide range of biomass samples, heating rates, data input format and equipment layout. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Resolution of structure characteristics of AE signals in multiphase flow system—From data to information
Authors: He Yi‐Jun , Wang Jing‐Dai , Cao Yi‐Jia , Yang Yong‐Rong
Published: July 2009

This investigation was performed to study the underlying structure characteristics of acoustic emission (AE) signals, which could be helpful not only to understand a relatively complete picture of hydrodynamics in multiphase flow systems, but also to extract the most useful information from the original signals with respect to a particular measurement requirement. However, due to AE signals are made up of emission from many acoustic sources at different scales, the resolution of AE signals is often very complicated and appears to be relatively poorly researched. In this study, the structure characteristics of AE signals measured both in gas–solid fluidized bed and liquid–solid stirred tank were researched in detail by resorting to wavelet transform and rescaled range analysis. A general criterion was proposed to resolve AE signals into three physical‐related characteristic scales, i.e., microscale, mesoscale, and macroscale. Multiscale resolution of AE signals implied that AE signals in microscale represented totally the dynamics of solid phase and could be applied to measure particle‐related properties. Furthermore, based on the structure characteristics of AE signals, useful features related to particles motion were extracted to establish two new prediction models, one for on‐line measurements of particle size distribution (PSD) and average particle size in gas–solid fluidized bed and the other for on‐line measurement of the suspension height in liquid–solid stirred tank. The prediction results indicated that (1) measurements of PSD and average particle size using AE method showed a fairly good agreement with that using sieve method both for laboratory scale and plant scale fluidized beds, and (2) measurements of the suspension height using AE method showed a fairly good agreement with that using visual method. The results thus validated that the extracted features based on analyses of structure characteristics of AE signals were very useful for establishing effective on‐line measurement models with respect to some particular applications. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Pre‐Columbian population dynamics in coastal southern Peru: A diachronic investigation of mtDNA patterns in the Palpa region by ancient DNA analysis
Authors: Fehren‐Schmitz Lars , Reindel Markus , Cagigao Elsa Tomasto , Hummel Susanne , Herrmann Bernd
Published: July 2009

Alternative models have been proposed to explain the formation and decline of the south Peruvian Nasca culture, ranging from migration or invasion to autochthonous development and ecological crisis. To reveal to what extent population dynamic processes accounted for cultural development in the Nasca mainland, or were influenced by them, we analyzed ancient mitochondrial DNA of 218 individuals, originating from chronologically successive archaeological sites in the Palpa region, the Paracas Peninsula, and the Andean highlands in southern Peru. The sampling strategy allowed a diachronic analysis in a time frame from approximately 800 BC to 800 AD. Mitochondrial coding region polymorphisms were successfully analyzed and replicated for 130 individuals and control region sequences (np 16021–16408) for 104 individuals to determine Native American mitochondrial DNA haplogroups and haplotypes. The results were compared with ancient and contemporary Peruvian populations to reveal genetic relations of the archaeological samples. Frequency data and statistics show clear proximity of the Nasca populations to the populations of the preceding Paracas culture from Palpa and the Peninsula, and suggest, along with archaeological data, that the Nasca culture developed autochthonously in the Rio Grande drainage. Furthermore, the influence of changes in socioeconomic complexity in the Palpa area on the genetic diversity of the local population could be observed. In all, a strong genetic affinity between pre‐Columbian coastal populations from southern Peru could be determined, together with a significant differentiation from ancient highland and all present‐day Peruvian reference populations, best shown in the differential distribution of mitochondrial haplogroups. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.
Development of low‐biofouling polypropylene feedspacers for reverse osmosis
Authors: Hausman Richard , Gullinkala Tilak , Escobar Isabel C.
Published: July 2009

Microbial fouling, or biofouling, is the accumulation of microorganisms onto material surfaces. The goal of this project was to develop low‐biofouling polypropylene (PP) films through the functionalization of PP by a spacer arm with metal chelating ligands charged with copper ions. Virgin and modified PP films were put in contact with 3.0 ×105
Escherichia coli cells/mL solutions for periods of time varying from 24 to 168 h. Fourier transform infrared spectroscopy (FTIR) and x‐ray energy dispersive spectroscopy (EDS) were used to verify the functionalization reactions and monitor copper leaching. Direct counts of cells stained with dsDNA showed, invariably, that the microbial attachment to the modified PP films was an order of magnitune lower than on the virgin PP. Further, over a period of time of 2 weeks, no significant amounts of copper leached from the low‐biofouling PP films. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Highly concentrated cationic flocculants based on 80/20 wt % [2‐(acryloyloxy)ethyl]trimethylammonium chloride/acrylamide in an inverse microemulsion: Influence of the copolymerization variables on the flocculation performance
Authors: Ochoa‐Gómez José R. , Nieto‐Mestre J. , Escudero‐Sanz Francisco J. , Sasia P. M. , Río F. , Torrecilla‐Soria J. , Katime Issa A.
Published: July 2009

The influence of the total comonomer concentration (TCC; 30–42 wt %), emulsifier concentration (EC; 7.3–23 wt %), hydrophilic–lipophilic balance (HLB; 9–9.9), crosslinking agent (N,N′‐methylene bisacrylamide) concentration (CAC; 0–122.8 ppm with respect to TCC), and isopropyl alcohol (chain‐transfer agent) concentration (IPC; 0–1.5 wt % with respect to TCC) on the flocculation performance (FP) of 80/20 wt % acrylamide (AM)/[2‐(acryloyloxy)ethyl]trimethylammonium chloride (ADQUAT) copolymers obtained by semicontinuous inverse microemulsion copolymerization was studied with capillary suction time testing for FP assessment on anaerobic digested sludges. FP increased as TCC decreased, was nearly unaffected by EC, was maximum with an HLB of 9.5, decreased strongly with CAC, and showed a peak value with an IPC of 1 wt %. At a very high TCC, copolymer growth in a highly collapsed state resulted in greatly structured, high weight‐average molar mass flocculants with decreased swelling capacities (SCs), which did not favor bridging flocculation, and in increased shielding of their positive charges, which did not favor charge neutralization flocculation. However, industrially needed latices with both high TCC and good FP could be obtained by the addition of isopropyl alcohol, which, below a concentration of 1 wt %, improved FP by decreasing the weight‐average molar mass and thereby enhancing SC while maintaining long enough chains to be effective for bridging flocculation. On the basis of the results, new star‐shaped ADQUAT/AM copolymers are envisioned as flocculants with superior FP. A synthetic route is proposed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Perfume‐containing polyurea microcapsules with undetectable levels of free isocyanates
Authors: Jacquemond Marlène , Jeckelmann Nicolas , Ouali Lahoussine , Haefliger Olivier P.
Published: July 2009

Core‐shell polyurea microcapsules with a 40% fragrance load were prepared by interfacial polymerization of guanidine and a technical polyisocyanate prepolymer containing mainly the biuret trimer derived from hexamethylene di‐isocyanate (HDI). Residual free polyisocyanates were still present at a level slightly above 100 mg NCO functional group per kg as determined by liquid chromatography hyphenated with tandem mass spectrometry of HDI and of its biuret trimer. This level was decreased by a factor of about 10 when the polymerization process was allowed to proceed for a longer time and by a factor of about 500 when guanidine or NaOH were added to the microcapsule suspension to act as scavengers. In these cases, polyisocyanate conversion was observed to proceed for about one month when the microcapsules were stored at room temperature before reaching a plateau at a level below 1 mg NCO/kg. Overall, ammonia was the most efficient polyisocyanate scavenger as no residual HDI biuret trimer and only less than 2 μg NCO/kg as HDI were detected at the end of the process, a level which had dropped below the limit of detection of 0.25 μg NCO/kg after about 40 days of aging at room temperature. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Poly(hydroxybutyrate‐co‐hydroxyvalerate)/titanium dioxide nanocomposites: A degradation study
Authors: Buzarovska Aleksandra , Grozdanov Anita , Avella M. , Gentile G. , Errico M.
Published: July 2009

Nanocomposites, based on a poly(hydroxybutyrate‐co‐hydroxyvalerate) (PHBV) matrix and titanium dioxide (TiO2) nanoparticles and fabricated with a solvent‐casting technique, were characterized with differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and Fourier transform infrared spectroscopy. The content of TiO2 nanoparticles varied between 0.5 and 10 wt %. Degradation studies, including hydrolytic degradation in a strong base medium (1N NaOH) and degradation under ultraviolet light at 365 nm, were performed. It was confirmed that the inorganic filler had no great influence on thermal properties such as the melting and crystallization temperatures. Improved degradation temperatures were also confirmed with the increase in the filler content. Degradation observations confirmed significant increases in hydrolytic erosion with the filler content increasing in comparison with the degradation of a pure PHBV film. Also, the photocatalytic activity of the inorganic filler TiO2 in all investigated composites [irradiated at λ = 365 nm and immersed in a liquid medium (H2O)] was evaluated. The degraded samples were analyzed with Fourier transform infrared spectroscopy, which confirmed their increased crystallinity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effects of the molecular weight of poly(ether imide) on the viscoelastic phase separation of poly(ether imide)/epoxy blends
Authors: Gan Wenjun , Xiong Wei , Yu Yingfeng , Li Shanjun
Published: July 2009

The phase separation of diglycidyl ether of bisphenol A/methyl tetrahydrophthalic anhydride blends modified with three poly(ether imide)s (PEIs) of different molecular weights was investigated with scanning electron microscopy (SEM) and time‐resolved light scattering (TRLS). The morphologies observed by SEM for the three blends were all close to a cocontinuous structure with different periodic distances. The results of TRLS indicated that the phase separation for the PEI‐modified epoxy blends took place according to the spinodal decomposition mechanism and the onset time of phase separation, with the periodicity of the phase structure depending on the PEI molecular weight and cure temperature. The time‐dependent peak scattering vector was simulated with a Maxwell‐type viscoelastic relaxation equation, indicating that the coarsening process of epoxy droplets was mainly controlled by the viscoelastic flow. Relaxation times obtained at different temperatures for the three blends could be described by the Williams–Landel–Ferry equation. The effects of the PEI molecular weight on the processes of viscoelastic phase separation were investigated, and the observed trends could be explained qualitatively through thermodynamic analysis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
An interactive method for teaching anatomy of the human eye for medical students in ophthalmology clinical rotations
Authors: Kivell Tracy L. , Doyle Sara K. , Madden Richard H. , Mitchell Terry L. , Sims Ershela L.
Published: July 2009

Much research has shown the benefits of additional anatomical learning and dissection beyond the first year of medical school human gross anatomy, all the way through postgraduate medical training. We have developed an interactive method for teaching eye and orbit anatomy to medical students in their ophthalmology rotation at Duke University School of Medicine. We provide review lectures on the detailed anatomy of the adult human eye and orbit as well as the developmental anatomy of the eye. These lectures are followed by a demonstration of the anatomy of the orbit using conventional frontal and superior exposures on a prosected human cadaver. The anatomy is projected onto a large LCD screen using a mounted overhead camera. Following a brief lecture on clinically relevant anatomy, each student then dissects a fresh porcine (pig) eye under low magnification using a dissecting microscope. These dissections serve to identify structures extrinsic to the eyeball, including extraocular muscle attachments, small vessels, optic nerve stalk, and fascial sheath of the eyeball (Tenon's fascia). Dissection then shifts to the internal anatomy of the eyeball. The size and anatomy of the porcine eye is comparable with that of the human and the dissection provides students with a valuable hands‐on learning opportunity that is otherwise not available in embalmed human cadavers. Students and clinical faculty feedback reveal high levels of satisfaction with the presentation of anatomy and its scheduling early during the ophthalmology clerkship. Anat Sci Educ 2:173–178, 2009. © 2009 American Association of Anatomists.
Undergraduate virology exercises demonstrate conventional and real‐time PCR using commercially available HIV primers and noninfectious target
Authors: Sulzinski Michael A. , Wasilewski Melissa A. , Farrell James C. , Glick David L.
Published: July 2009

It is an extraordinary challenge to offer an undergraduate laboratory course in virology that teaches hands‐on, relevant molecular biology techniques using nonpathogenic models of human virus detection. To our knowledge, there exists no inexpensive kits or reagent sets that are appropriate for demonstrating real‐time PCR (RT‐PCR) in an undergraduate laboratory course in virology. Here we describe simple procedures for student exercises that demonstrate the PCR detection of an HIV target nucleic acid. Our procedures combine a commercially available kit for conventional PCR with a modification for RT‐PCR using the same reagents in the kit, making it possible for an instructor with access to a LightCycler® instrument to implement a relevant student exercise on RT‐PCR detection of HIV nucleic acid targets. This combination of techniques is useful for demonstrating and comparing conventional PCR amplification and detection with agarose gel electrophoresis, with real‐time PCR over a series of three laboratory periods. The series of laboratory periods also is used to provide the foundation for teaching the concept of PCR primer design, optimization of PCR detection systems, and introduction to nucleic acid queries using NCBI‐BLAST to find and identify primers, amplicons, and other potential amplification targets within the HIV viral genome. The techniques were successfully implemented at the Biology 364 undergraduate virology course at the University of Scranton during the Fall 2008 semester. The techniques are particularly targeted to students who intend to pursue either postgraduate technical employment or graduate studies in the molecular life sciences.
A simple test tube‐based ELISA experiment for the high‐school classroom
Authors: Brokaw Ann , Cobb Brian A.
Published: July 2009

Immunology is gaining prominence both in the media as well as on the Advanced Placement (AP) exam in Biology. One of the challenges of teaching modern biological topics such as immunology and biochemistry in the high‐school setting is the increased reliance on expensive technology in the research world. To begin to bridge this widening gap, we devised an experiment using a novel macroscale enzyme‐linked immunosorbent assay that is suitable for AP‐level high‐school biology classrooms as well as entry‐level collegiate laboratories. This novel method does not require a plate reader for data analysis, but instead relies on more common and inexpensive equipment such as a clinical test tube centrifuge and a simple test tube spectrophotometer. The experimental plan focuses on students measuring antibody concentrations in “unknown” samples and includes the collection and analysis of a standard curve using reagents prepared by the instructor. Students will be introduced to enzyme action, quantitative laboratory technique, antibodies, and the immune system, with the overall goal being to explore and highlight the inherent connections within the fields of biochemistry and immunology.
A single nutrient feed supports both chemically defined NS0 and CHO fed‐batch processes: Improved productivity and lactate metabolism
Authors: Ma Ningning , Ellet JoAnn , Okediadi Centy , Hermes Paul , McCormick Ellen , Casnocha Susan
Published: July 2009

A chemically defined nutrient feed (CDF) coupled with basal medium preloading was developed to replace a hydrolysate‐containing feed (HCF) for a fed‐batch NS0 process. The CDF not only enabled a completely chemically defined process but also increased recombinant monoclonal antibody titer by 115%. Subsequent tests of CDF in a CHO process indicated that it could also replace the hydrolysate‐containing nutrient feed in this expression system as well as providing an 80% increase in product titer. In both CDF NS0 and CHO processes, the peak lactate concentrations were lower and, more interestingly, lactate metabolism shifted markedly from net production to net consumption when cells transitioned from exponential to stationary growth phase. Subsequent investigations of the lactate metabolic shift in the CHO CDF process were carried out to identify the cause(s) of the metabolic shift. These investigations revealed several metabolic features of the CHO cell line that we studied. First, glucose consumption and lactate consumption are strictly complementary to each other. The combined cell specific glucose and lactate consumption rate was a constant across exponential and stationary growth phases. Second, Lactate dehydrogenase (LDH) activity fluctuated during the fed‐batch process. LDH activity was at the lowest when lactate concentration started to decrease. Third, a steep cross plasma membrane glucose gradient exists. Intracellular glucose concentration was more than two orders of magnitude lower than that in the medium. Fourth, a large quantity of citrate was diverted out of mitochondria to the medium, suggesting a partially truncated tricarboxylic acid (TCA) cycle in CHO cells. Finally, other intermediates in or linked to the glycolytic pathway and the TCA cycle, which include alanine, citrate, isocitrate, and succinate, demonstrated a metabolic shift similar to that of lactate. Interestingly, all these metabolites are either in or linked to the pathway downstream of pyruvate, but upstream of fumarate in glucose metabolism. Although the specific mechanisms for the metabolic shift of lactate and other metabolites remain to be elucidated, the increased understanding of the metabolism of CHO cultures could lead to future improvements in medium and process development. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Development of a high throughput protein a well‐plate purification method for monoclonal antibodies
Authors: Hopp Jennifer , Pritchett Ross , Darlucio Maria , Ma Junfen , Chou Judy H.
Published: July 2009

We have developed a new high throughput method for the purification of monoclonal antibodies from harvested cell culture fluid for analytical characterization. This method uses Protein A resin in a 96 well‐plate format with protein loading sufficient to perform multiple analyses per well. Resin and buffer conditions were optimized to obtain aggregate and charge variant comparability with three preparative Protein A purified monoclonal antibodies. We are able to successfully demonstrate comparability for aggregate within 0.25% based upon size‐exclusion chromatography. Acidic species were found to be within 2% from the preparative purified control based upon cation‐exchange chromatography, 5% based upon capillary zone electrophoresis, and 3% based upon imaged capillary isoelectric focusing. Glycan distribution was analyzed and was within 1% of the preparative purified controls. A tryptic digest was performed and all peaks in the preparative purified control were found in the first elution from the well‐plate format. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Parallel gene cloning and protein production in multiple expression systems
Authors: Wang Hui‐Min , Shih Yan‐Ping , Hu Su‐Ming , Lo Wen‐Tsung , Lin Hui‐Min , Ding Shih‐Shiu , Liao Hsin‐Chi , Liang Po‐Huang
Published: July 2009

To quickly find an optimal expression system for recombinant protein production, a set of vectors with the same restriction sites were constructed for parallel cloning of a target gene and recombinant protein production in prokaryotic and eukaryotic expression systems, simultaneously. These vectors include nucleotide sequences encoding protein tags and protease recognition sites for tag removal, followed by the cloning sites 5′‐EcoRI/3′‐XhoI identical in these vectors for ligating with the sticky‐end PCR product of a target gene. Our vectors allow parallel gene cloning and protein production in multiple expression systems with minimal cloning effort. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
A radiologic and histologic study of the os peroneum: Prevalence, morphology, and relationship to degenerative joint disease of the foot and ankle in a cadaveric sample
Authors: Muehleman C. , Williams J. , Bareither M.L.
Published: July 2009

The present study investigated the prevalence of an os peroneum (OP, a sesamoid bone) in a cadaveric sample and its relationship to the shape of the cuboid tuberosity, and cartilage degeneration at the cuboid tuberosity and in regional joints within the foot (first metatarsophalangeal and calcaneocuboid) and ankle. The fibularis longus tendon of 33 embalmed human cadavers (mean age 81 years) were obtained from the anatomy laboratory. Nineteen of 64 tendons (30%) displayed an OP both radiographically and histologically. The os peronei ranged in size from small spicules to prominent masses: mean area 2.48 mm2 (left) and 2.70 mm2 (right). Histologically, the os peronei were cancellous bone, the largest occupying most of the tendon at the point of contact with the cuboid tuberosity. Fibrocartilage was present at their borders, merging with dense regular fibrous tissue and peritenon. The talocrural, calcaneocuboid, and first metatarsophalangeal joints were examined for cartilage integrity and osteophytes based on an earlier suggestion that there may be an association between degenerative joint disease and endochondral bone formation. There was no statistical correlation between presence of an OP with any of the following parameters: age, gender, body size, cartilage degeneration, or osteophytes within any of the joints examined. Therefore, the presence of an OP does not appear to be associated with increased endochondral ossification or degenerative joint disease. This study does not preclude the possibility that sesamoid bone formation may be associated with biomechanical functions within the foot; thus, future studies may be warranted. Clin. Anat. 22:747–754, 2009. © 2009 Wiley‐Liss, Inc.
Novel insights into the elastic and muscular components of the human trachea
Authors: Kamel Kirollos Salah , Beckert Lutz E. , Stringer Mark D.
Published: July 2009

Despite its probable importance in health and disease, the elastic tissue in the trachea has rarely been investigated. In addition, various aspects of the trachealis muscle are controversial. The aim of this study was to clarify this clinically relevant anatomy. Ten cadaveric tracheobronchial specimens (age range 68–101 years; seven males; no major airway pathology) were qualitatively investigated by microdissection. Serial histologic sections from multiple sites in three specimens were analyzed after staining for elastin. Findings were correlated with observations from video tracheobronchoscopies. An extensive and prominent meshwork of elastic tissue was found within the trachea and bronchi. Elastic fibers were predominantly longitudinal and aggregated into discrete bundles within the membranous wall of the trachea and main bronchi; a discrete fibroelastic membrane bridging the membranous wall of the trachea; and vertical laminae connecting the ends of successive cartilages. The longitudinal elastic bundles continued into the segmental bronchi, becoming thinner and more circumferentially distributed. Trachealis consisted of a transverse layer of smooth muscle deep to the fibroelastic membrane of the membranous wall of the trachea, together with scattered longitudinal muscle bundles, mostly embedded within the fibroelastic membrane in the distal half of the trachea. In conclusion, there is an extensive but relatively neglected elastic framework within the tracheobronchial tree. This is likely to have major clinical relevance to the pathophysiology of respiratory disease and ageing. The trachealis muscle is more complex than previously stated. Clin. Anat. 22:689–697, 2009. © 2009 Wiley‐Liss, Inc.
Psychopathy and offence severity in sexually aggressive and violent youth
Authors: Fougere Amber , Potter Susan , Boutilier Joan
Published: July 2009

Background A large proportion of violent crimes are committed by youths. Youths with psychopathic traits may have a higher risk for recidivism and violence.

Aims/hypotheses Our aim was to compare sexually aggressive with violent young men on offence severity and psychopathy. Three hypotheses were proposed: first, young men with previous offences would display a progressive increase in seriousness of offence during their criminal career; secondly, the sexually aggressive and violent young men would not differ in scores on the Hare Psychopathy Checklist: Youth Version (PCL:YV); but, thirdly, PCL:YV scores would be positively correlated with the severity of the index crime, as measured by the Cormier–Lang System for Quantifying Criminal History.

Methods Information was collected from the files of 40 young men in conflict with the law, and the PCL:Youth Version (YV) rated from this by trained raters.

Results The offences of these young men became more serious over time, but we found no association between PCL:YV scores and offence type or seriousness.

Conclusions and implications This exploratory research suggests the importance of understanding the progression in offending careers, but a limited role for the PCL:YV in doing so. Given the small sample size, however, and the limit on access to information about details of age, the findings need replication. Copyright © 2009 John Wiley & Sons, Ltd.
First experience With the biostar‐device for various applications in pediatric patients With congenital heart disease
Authors: Hoehn Rene , Hesse Carola , Ince Hüseyin , Peuster Matthias
Published: July 2009

Background: Interventional closure of atrial septal defects (ASD) and surgical tunnel fenestrations in Fontan patients has become the procedure of choice for many years. Recently, the BioSTAR Occluder, a modification of the Starflex device with a resorbable matrix has become available. Patients: Ten Biostar devices were implanted in nine children with interatrial septal defects, one within a fontan baffle, eight with secundum atrial septal defects. The age of the patients ranged from 11 months to 17 years, the body weight ranged from 12.9–78 kg. Results: 10 BioSTAR devices were implanted in nine patients. In one patient, two BioSTAR devices were used to occlude multiple defects within the oval fossa. All defects were successfully and uneventfully occluded. Mean procedure time was 56 (range 28–125). Mean fluoroscopy time was 4.8 (range 1.1 to 13.0) min. None of the nine patients showed residual shunts after device implantation. After 30 days no shunt was seen in the control transthoracic echocardiography. No adverse effects like allergic reactions, tachyarrhythmia or thrombembolic events occurred in any of the patients. Conclusion: The BioSTAR closure device is a safe and effective device for the closure of a variety of interatrial shunts in children including multifenestrated interatrial defects and fontan fenestrations, however, possible long term consequences (e.g., fractures, recurrent shunts after scaffold degradation) remain to be studied. © 2009 Wiley‐Liss, Inc.
Microvascular obstruction after percutaneous coronary intervention
Authors: Lee Chi‐Hang , Tse Hung‐Fat
Published: July 2009

Successful revascularization of the epicardial coronary artery can be achieved in over 90% of percutaneous coronary intervention (PCI) procedures. However, postprocedural microvascular obstruction, despite the presence of normal epicardial flow, remains an important limitation which substantially reduces the beneficial effects of PCI. In this review article, a number of different methods available to diagnose microvascular obstruction after PCI are outlined. We also discussed the various pharmacological and mechanical strategies to reduce the occurrence of microvascular obstruction. In this regard, pretreatment with antiplatelet therapy remains crucial. In urgent PCI for acute myocardial infarction, available data suggest that manual thrombus aspiration device is beneficial in reducing the occurrence of procedure‐related microvascular obstruction and possibly improve long‐term clinical outcomes.© 2009 Wiley‐Liss, Inc.
Autothermal Reforming of Methane in a Reverse‐Flow Reactor
Authors: Liu T. , Temur H. , Veser G.
Published: July 2009

Autothermal methane reforming (ATR) is an alternative to steam reforming for synthesis gas and hydrogen production. It meets the intensive energy demand of methane reforming by combining exothermic oxidation and endothermic steam reforming. However, ATR runs into autothermal limitations if the water‐to‐oxygen feed ratio is increased to optimize hydrogen production. We have previously shown that regenerative heat integration in a reverse‐flow reactor (RFR) can overcome autothermal limitations in syngas production via catalytic partial oxidation of methane. Here, we extend our studies onto ATR in a RFR. Our results show that regenerative heat integration strongly increases the range of autothermal operation for ATR towards higher H2O:CH4 feed ratios. RFR operation allows for improved syngas yields and much higher H2/CO ratios in the product stream. Improvements are most pronounced for high flow rates, which makes ATR‐RFR particularly well suited to compact reactors for small‐scale and decentralized processes.
Multicomponent Mass Transfer Model for Supercritical Extraction: Application to Isopropyl Alcohol Production
Authors: Pfeuffer B. , Kunz U. , Hoffmann U. , Turek T.
Published: July 2009

A multicomponent mass transfer model based on the generalized Maxwell‐Stefan equations (GMS) for an extraction process with supercritical fluids is presented. The solution is obtained from the differential film model equations rather than from an explicit expression for the fluxes. The approach presented here also provides concentration profiles along the diffusion path length, which allow rigorous consideration of the dependence of mass transfer coefficients and thermodynamic factors on concentration, if desired. The volume translated Peng‐Robinson equation of state is used along with a gE mixing rule (gE – molar excess Gibbs free energy) in order to account for strongly nonideal thermodynamics that necessarily arise in unstable liquid mixtures. The results show strong diffusional coupling effects for the system under consideration, propene (1)‐isopropyl alcohol (2)‐water (3). Finally, we demonstrate how diffusional coupling may provide options for process intensification.
Study of stability and thermodynamic properties for polychlorinated dihydrophezines by density functional theory
Authors: Liu Hong X. , Yang Guo Y. , Wang Zun Y. , Wang Lian S.
Published: July 2009

The thermodynamic properties of 76 polychlorinated dihydrophezines (PCDPs) in the gaseous state at 298.15 K and 101.325 kPa, have been calculated using the density functional theory (the BHANDHLYP/6‐31G*) with Gaussian 03 program. Based on these data, the isodesmic reactions were designed to calculate the standard formation heat (ΔfHθ), standard Gibbs free energy of formation (ΔfGθ) of PCDPs in the gaseous state. The relations of these thermodynamic parameters with the number and position of chlorine substituents (NPCS) were discussed, and it was found that there exist good correlation between thermodynamic parameters, including heat capacity at constant volume $(C_{\rm v}^\theta )$, entropy (Sθ), enthalpy (Hθ), free energy (Gθ), ΔfHθ, ΔfGθ, and NPCS. The relative stability order of PCDP congeners was theoretically proposed based on the relative magnitude of their ΔfGθ. In addition, the values of molar heat capacity at constant pressure (Cp,m) for PCDP congeners have been calculated.
Removal of Brill Red 5B from an aqueous solution using Cicca acida biomass
Authors: Karthik V. , Velan M. , Kumar M. Dharmendira , Renganathan S.
Published: July 2009

The biosorption of Brill Red 5B from an aqueous solution, using Cicca acida plant's leaves was investigated in a batch system with the influence of pH (1–6), temperature (25–35°C) and initial dye concentration (10–100 mg/L). Maximum biosorption was observed at initial pH of 2.0, temperature of 30°C and at the initial dye concentration of 100 mg/L. Batch biosorption kinetic was studied using the pseudo first and pseudo‐second‐order rate equations. From the result, it was observed that pseudo‐second‐order rate expression fitted the experimental data well when compared to pseudo first order kinetic model. The intra‐particle diffusion coefficient (Ki) and effective diffusion coefficient (Di) values obtained for the sorption of Brill Red 5B using C. acida plant's leaves were found to be increased with increase in initial dye concentration.
Optimization of acrylonitrile removal by activated carbon‐granular using response surface methodology
Authors: Kumar Arvind , Prasad B. , Mishra I. M.
Published: July 2009

A statistical Box–Behnken design of experiments was performed to evaluate the effects of individual operating variables and their interactions on the acrylonitrile (AN) removal of C0 = 100 mg/L as fixed input parameter. The variables examined in this study included activated carbon‐granular (AC) dosage, w, temperature, T, and time of contact, t. The significant variables and optimum conditions were identified (w = 4 g/L, T = 30°C, and t = 120 min with AN uptake of 23.97 mg/g of AC) from statistical analysis of the experimental results using response surface methodology (RSM).
Porous polymer monolith templated by small polymer molecules
Authors: Wu Zhiwang , Frederic Kyle J. , Talarico Mark , De Kee Daniel
Published: July 2009

Porous poly(ethylene glycol) diacrylate (PEGDA) monoliths have been prepared by UV‐initiated polymerization of PEGDA oligomer (Mn = 700 g/mol). In the mean time, the addition of hydrophobic poly(propylene oxide) (PPO, Mn = 725 g/mol) as porogen into an ethanol solution of PEGDA oligomer to form a homogenous mixture, causes a phase separation between PPO and PEGDA following removal of ethanol by UV heating. Porous PEGDA monolith was prepared by immediate heating at 300°C to remove PPO molecules from the as‐synthesized PEGDA/PPO hybrid. The micrometer pores of the PEGDA monolith have relatively concentrated pore size distribution according to the mercury intrusion porosimetry results and field emission scanning electron microscopy (FE‐SEM).
Confirmation of control valve stiction in interacting systems
Authors: Haoli Yu , Lakshminarayanan S. , Kariwala Vinay
Published: July 2009

Stiction in a control valve generates limit cycles which can propagate to the connecting units, resulting in plant‐wide oscillations and impacting the overall process performance. For stiction confirmation, Choudhury et al. [Choudhury et al., CJChE 2007;85:208–219] introduced the controller gain change method, which is based on the change in the oscillation frequency due to changes in the controller gain. In this paper, we show that this method can fail to accurately isolate and confirm the presence of the sticky valve in interacting multi‐input multi‐output systems. We propose a strategy based on the magnitude of relative change in oscillation frequency due to changes in controller gain to overcome the limitations of the existing method. The effectiveness of the proposed method is demonstrated using simulation studies.
Kinetic study of Fe removal from precipitated silica prepared from yellow phosphorus slag
Authors: Su Yi , Li Guo Bing , Xia Ju Pei
Published: July 2009

This purification process may be described by the unreacted shrink core model with solid resultant (inert material) and fixed particle size, which is carried out by the action of nitric acid solution on the precipitated silica obtained from yellow phosphorus slag which was leached with phosphoric acid. The study results indicate that the purification process is a chemical reaction controlling step and its apparent activation energy Ea is 30.354 kJ/mol, with reaction order 0.6746.
A longitudinal study of children's aggressive behaviours based on multivariate mixed models with incomplete data
Authors: Wu Lang , Liu Wei , Liu Juxin
Published: July 2009

The authors consider children's behavioural and emotional problems and their relationships with possible predictors. They propose a multivariate transitional mixed‐effects model for a longitudinal study and simultaneously address non‐ignorable missing data in responses and covariates, measurement errors in covariates, and multivariate modelling of the responses and covariate processes. A real dataset is analysed in details using the proposed method with some interesting results. The Canadian Journal of Statistics 37: 435–452; 2009 © 2009 Statistical Society of Canada
Large deviations of multiclass M/G/1 queues
Authors: Dabrowski André , Lee Jiyeon , McDonald David R.
Published: July 2009

Consider a multiclass M/G/1 queue where queued customers are served in their order of arrival at a rate which depends on the customer class. We model this system using a chain with states represented by a tree. Since the service time distribution depends on the customer class, the stationary distribution is not of product form so there is no simple expression for the stationary distribution. Nevertheless, we can find a harmonic function on this chain which provides information about the asymptotics of this stationary distribution. The associated h‐transformation produces a change of measure that increases the arrival rate of customers and decreases the departure rate thus making large deviations common. The Canadian Journal of Statistics 37: 327–346; 2009 © 2009 Statistical Society of Canada
A phase 2 study of yttrium‐90 ibritumomab tiuxetan (Zevalin) in patients with chronic lymphocytic leukemia
Authors: Jain Nitin , Wierda William , Ferrajoli Alessandra , Wong Franklin , Lerner Susan , Keating Michael , O'Brien Susan
Published: July 2009

BACKGROUND:

Radioimmunotherapy (RIT) with radio‐labeled monoclonal antibodies to CD20 produce a high response rate in patients with relapsed lymphoma. Use of this modality in patients with chronic lymphocytic leukemia (CLL) has been hampered by the extensive marrow involvement seen in patients with CLL, which would produce a high risk for marrow aplasia after treatment with RIT. Patients with lymphoma and marrow involvement have been treated with RIT if involved marrow was less than 25% of the total marrow. Thus, we adapted this approach as consolidation therapy in patients with CLL responding to chemoimmunotherapy.

METHODS:

Fourteen patients with relapsed CLL either in partial remission or in complete remission but with disease documented by flow cytometry were treated with 90Y ibritumomab tiuxetan.

RESULTS:

One patient responded and achieved a complete remission but with residual disease detected by flow cytometry. Of note was that grade 3 or 4 hematologic toxicity was seen in 12 of the 13 (92%) evaluable patients, with grade 3 or 4 thrombocytopenia noted in 11 (85%) of the patients. In addition, myelosuppression was prolonged with a median duration of grade 3 or 4 thrombocytopenia of 37 days. Five patients had persistent thrombocytopenia 3 months post‐therapy.

CONCLUSIONS:

Even in patients with CLL and limited marrow involvement, the use of RIT results in unacceptable hematologic toxicity. Cancer 2009. © 2009 American Cancer Society.
Comparison of hospitalization risk and associated costs among patients receiving sargramostim, filgrastim, and pegfilgrastim for chemotherapy‐Induced neutropenia
Authors: Heaney Mark L. , Toy Edmond L. , Vekeman Francis , Laliberté François , Dority Bree L. , Perlman Daniel , Barghout Victoria , Duh Mei Sheng
Published: July 2009

BACKGROUND:

Sargramostim is a granulocyte‐macrophage–colony‐stimulating factor (GM‐CSF). Unlike filgrastim and pegfilgrastim, which are granulocyte–colony‐stimulating factors (G‐CSFs), sargramostim activates a broader range of myeloid lineage‐derived cells. Therefore, GM‐CSF might reduce infection risk more than the G‐CSFs. This study compared real‐world infection‐related hospitalization rates and costs in patients using G/GM‐CSF for chemotherapy‐induced neutropenia.

METHODS:

This retrospective matched‐cohort study analyzed nationally representative health insurance claims in the United States from 2000 through 2007. The sample population included patients who received chemotherapy and G/GM‐CSF. G/GM‐CSF treatment episodes began with the first administration of G/GM‐CSF and ended when a subsequent administration was >28 days after a prior administration. Sargramostim patients were matched 1:1 with filgrastim and pegfilgrastim patients based on gender and birth year. Outcomes included infection‐related hospitalization rates and the associated costs. Hospitalization rates were analyzed using univariate and multivariate Poisson methods; covariates included myelosuppressive agents received, tumor type, anemia, and comorbidities.

RESULTS:

A total of 990 sargramostim‐filgrastim and 982 sargramostim‐pegfilgrastim matched pairs were analyzed. Cohorts were similar with regard to age, gender, and comorbid conditions. Several differences were observed with regard to tumor type, anemia, and chemotherapy, but no systematic trends were apparent. Sargramostim patients experienced a 56% lower risk of infection‐related hospitalizations compared with filgrastim and pegfilgrastim patients. Infection‐related hospitalization costs were 84% and 62% lower for sargramostim patients compared with patients treated with filgrastim and pegfilgrastim, respectively.

CONCLUSIONS:

Among patients with or at risk for chemotherapy‐induced neutropenia, these data indicated that use of sargramostim was associated with a reduced risk of infection‐related hospitalization and lower associated costs compared with filgrastim or pegfilgrastim. Cancer 2009. © 2009 American Cancer Society.
Randomized controlled trials of the efficacy of lung cancer screening by sputum cytology revisited
Authors: Doria‐Rose V. Paul , Marcus Pamela M. , Szabo Eva , Tockman Melvyn S. , Melamed Myron R. , Prorok Philip C.
Published: July 2009

BACKGROUND:

Two randomized controlled trials of lung cancer screening initiated in the 1970s, the Johns Hopkins Lung Project and the Memorial Sloan‐Kettering Lung Study, compared 1 arm that received annual chest X‐ray and 4‐monthly sputum cytology (dual‐screen) to a second arm that received annual chest X‐ray only. Previous publications from these trials reported similar lung cancer mortality between the 2 groups. However, these findings were based on incomplete follow‐up, and each trial on its own was underpowered to detect a modest mortality benefit.

METHODS:

The authors estimated the efficacy of lung cancer screening with sputum cytology in an intention‐to‐screen analysis of lung cancer mortality, using combined data from these trials (n = 20,426).

RESULTS:

Over ½ of squamous cell lung cancers diagnosed in the dual‐screen group were identified by cytology; these cancers tended to be more localized than squamous cancers diagnosed in the X‐ray only arm. After 9 years of follow‐up, lung cancer mortality was slightly lower in the dual‐screen than in the X‐ray only arm (rate ratio [RR], 0.88; 95% confidence interval [CI], 0.74‐1.05). Reductions were seen for squamous cell cancer deaths (RR, 0.79; 95% CI, 0.54‐1.14) and in the heaviest smokers (RR, 0.81; 95% CI, 0.67‐1.00). There were also fewer deaths from large cell carcinoma in the dual‐screen group, although the reason for this is unclear.

CONCLUSIONS:

These data are suggestive of a modest benefit of sputum cytology screening, although we cannot rule out chance as an explanation for these findings. Cancer 2009. © 2009 American Cancer Society.