bluuebunny/crossref_metadata_2025 huggingface dataset:
Characteristics of malfunctioning channels in pediatric cochlear implants
Authors: Lin Jerry W. , Mody Avni , Tonini Ross , Emery Claudia , Haymond Jody , Vrabec Jeffrey T. , Oghalai John S.
Published: November 2009

Objectives/Hypothesis:

To examine the characteristics of pediatric cochlear implant channel malfunction preceding device failure.

Study Design:

Retrospective review.

Methods:

All pediatric patients who underwent cochlear implantation at a tertiary academic medical center were reviewed regarding device type, reason for replacement, time to replacement, and timing and pattern of channel faults in failed versus nonfailed devices.

Results:

Between 1993 and 2008, 264 pediatric cochlear implantations were performed. With an average 894‐day follow‐up, the replacement rate was 9.5% (25/264). Reasons for replacement were device failure (6.4%), medical/surgical failure (2.3%), and obsolescence (0.8%). Replacement rates were comparable among Advanced Bionics (13.3%), Cochlear Corporation (6.3%), and MED‐EL (10.3%) devices. Fifty‐two cochlear implants developed at least one channel fault, and 13 eventually progressed to failure requiring replacement. MED‐EL devices comprised 12 of these 13 failures. At the 12‐month follow‐up interval, one, three, and five channel faults predicted 40%, 75%, and 100% probabilities of eventual electrode failure, respectively. Channels destined to fail demonstrated small, yet statistically significant, impedance elevations 12 months before failure and large elevations 3 months before failure.

Conclusions:

Replacement of cochlear implants in pediatric patients is common and is due to device malfunction about one half of the time. Earlier initial channel fault, earlier subsequent channel faults, adjacent channel faults, and a greater total number of channel faults were associated with the need for replacement surgery. Elevations in a channel's impedance should raise the concern for an impending failure. These predictors can help the cochlear implant team when considering surgery to replace the device. Laryngoscope, 2010
Ergonomic analysis of microlaryngoscopy
Authors: Statham Melissa McCarty , Sukits Alison L. , Redfern Mark S. , Smith Libby J. , Sok John C. , Rosen Clark A.
Published: November 2009

Objectives/Hypothesis:

To apply ergonomic principles in analysis of three different operative positions used in laryngeal microsurgery.

Study Design:

Prospective case‐control study.

Methods:

Laryngologists were studied in three different microlaryngeal operative positions: a supported position in a chair with articulated arm supports, a supported position with arms resting on a Mayo stand, and a position with arms unsupported. Operative positions were uniformly photographed in three dimensions. Full body postural data was collected and analyzed using the validated Rapid Upper Limb Assessment (RULA) tool to calculate a risk score indicative of potential musculoskeletal misuse in each position. Joint forces were calculated for the neck and shoulder, and compression forces were calculated for the L5/S1 disc space.

Results:

Higher‐risk postures were obtained with unfavorably adjusted eyepieces and lack of any arm support during microlaryngeal surgery. Support with a Mayo stand led to more neck flexion and strain. Using a chair with articulated arm supports leads to decreased neck strain, less shoulder torque, and decreased compressive forces on the L5/S1 disc space. Ideal postures during microlaryngoscopy place the surgeon with arms and feet supported, with shoulders in an unraised, neutral anatomic position, upper arms neutrally positioned 20° to 45° from torso, lower arms neutrally positioned 60° to 100° from torso, and wrists extended or flexed <15°.

Conclusions:

RULA and biomechanical analyses have identified lower‐risk surgeon positioning to be utilized during microlaryngeal surgery. Avoiding the identified high‐risk operative postures and repetitive stress injury may lead to reduced occupationally related musculoskeletal pain and may improve microsurgical motor control. Laryngoscope, 2010
Effect of cochleostomy size on perilymph fistula control
Authors: Robey Ashley B. , Craig Catherine A. , Lyden Elizabeth R. , Lusk Rodney P.
Published: November 2009

Objectives/Hypothesis:

Although the overall incidence of perilymphatic gushers is approximately 1%, patients with inner ear anomalies are at an increased risk for development of perilymphatic gushers. As cochlear implantation becomes more common in patients with inner ear anomalies (e.g., Mondini defect or common cavity defect), the ability to successfully seal such leaks becomes of paramount importance to reduce the risk of subsequent meningitis.

Methods:

A 1.0‐mm and a 1.5‐mm cochleostomy were placed superior to the round window in two respective temporal bones. Cochlear implant electrodes (Cochlear [Lane Cove NSW, Australia], Med‐El [Insbruck, Austria] and Advanced Bionics [Valencia, CA]) were placed in the cochleostomy and sealed with porcine periosteum. A fixed amount of pressure was applied to the inner ear, and the presence or absence of a leak was recorded for 10 different packings of each cochleostomy diameter at 0, 10, 15, 20, and 30 cm H2O.

Results:

For the Cochlear, Med‐El, and Advanced Bionics electrode, no statistically significant difference was noted between the 1.0‐mm and the 1.5‐mm cochleostomy at 0, 10, 15, and 20 cm H2O. At 30 cm H2O, no leaks were noted with the 1.5‐mm cochleostomy for any brand. For the 1.0‐mm cochleostomy at 30 cm H2O, 6/10 of the Cochlear trials leaked (P = .004), 2/10 of the Med‐El trials leaked (P = .24), and 5/10 of the Advanced Bionics trials leaked (P = .03).

Conclusions:

The 1.5‐mm cochleostomies are associated with a decreased risk of perilymphatic fistula as compared to 1.0‐mm cochleostomies at 30 cm H2O; this likely represents a phenomenon of packing adequacy. Laryngoscope, 2010
Targeted imaging modality selection for bacterial biofilms in chronic rhinosinusitis
Authors: Foreman Andrew , Singhal Deepti , Psaltis Alkis J. , Wormald Peter‐John
Published: November 2009

Objectives/Hypothesis:

Biofilms are increasingly recognized as having an etiological role in chronic rhinosinusitis (CRS). Research into biofilms in CRS currently relies on microscopic imaging techniques, none of which are universally accepted. This study compares LIVE/DEAD BacLight (Invitrogen Corp., Carlsbad, CA) staining and fluorescence in situ hybridization (FISH), both utilizing the confocal scanning laser microscope (CSLM) for biofilm determination and characterization in CRS patients.

Study Design:

Prospective study.

Methods:

Twenty CRS patients undergoing endoscopic sinus surgery were recruited for the study. Sinus mucosal tissue harvested at the time of surgery underwent both the BacLight/CSLM and FISH/CSLM protocols for biofilm determination and characterization.

Results:

Combining the results of both protocols, 18/20 (90%) patients had bacterial biofilms demonstrable on at least one modality. The high biofilm detection rate combining the two techniques suggests the prevalence of biofilms in CRS may be greater than previously reported. The protocols had equivalent results in 15/20 patients. Using the differences observed in the remaining five patients, we can highlight the most appropriate use for each technique.

Conclusions:

BacLight/CSLM and FISH/CSLM are complementary techniques for biofilm determination and characterization. Both protocols are suited to different research areas and the selection of technique used should be based on the specific objectives of the research protocol. In this way we can utilize the advantages of each technique to facilitate effective research. Laryngoscope, 2010
Language performance in children with cochlear implants and additional disabilities
Authors: Meinzen‐Derr Jareen , Wiley Susan , Grether Sandra , Choo Daniel I.
Published: November 2009

Objectives/Hypothesis:

Quantify post‐cochlear implant (CI) language among children with disabilities and determine the role of nonverbal cognitive quotients (NVCQ) in predicting language.

Study Design:

Small cohort study in pediatric tertiary care center.

Methods:

Children (n = 20) with CIs and developmental disabilities were enrolled. Receptive and expressive language was reported as language quotients (LQs). Pre‐ and post‐CI LQs were compared using the signed‐rank test. Multiple regression models analyzed language while controlling for possible confounders.

Results:

Five subjects had symptomatic cytomegalovirus, and four subjects had CHARGE syndrome with hearing loss etiology. Seventy‐five percent had cognitive deficits, and 55% had motor delays. Median age of CI was 24 months; median CI duration was 27.7 months. The range of NVCQs for the study cohort was 27 to 115. Fifteen subjects had NVCQs <80. Age at implantation, income, and number of siblings were not correlated with language. Although children had significant increases in language age pre‐ to post‐CI, median LQs did not significantly change after implantation. NVCQ, age at hearing loss diagnosis, implant duration, and number of different therapies attended were significant in models. NVCQ contributed the most unique variance (67%; P = .0003). Pre‐CI language performance did not predict post‐CI performance.

Conclusions:

This study is the first step in addressing the effects of CIs on language among children with disabilities. Progress in language skills occurred for all participants, although rates of progress were slow and highly variable. NVCQ was the strongest predictor of language, although cognition is not always sufficient for good language development. Adapting therapeutic strategies may be essential to impact greater language progress in these complex children. Laryngoscope, 2010
Characterization of binding affinities in a chromatographic system by suspended state HR/MAS NMR spectroscopy
Authors: Friebolin Volker , Marten Silvia , Albert Klaus
Published: November 2009

In the current work a racemate of (R)‐ and (S)‐benzylmandelate was separated with a stereoselective polysaccharide‐based chiral stationary phase by HPLC. To elucidate the occurring chiral molecular recognition processes in the heterogeneous system used, NMR spectroscopy was chosen under high resolution/magic angle spinning (HR/MAS) NMR conditions in the suspended state. Therefore, and as a proof of concept, a combination of several NMR methods such as spin–lattice relaxation time (T1) measurements (T1), the saturation transfer difference, and the 2D experiment of the transferred nuclear overhauser enhancement spectroscopy technique were applied. With HR/MAS NMR it is feasible to combine NMR and chromatography to achieve further insights into the separation process. Copyright © 2009 John Wiley & Sons, Ltd.
Real‐time MR thermometry for monitoring HIFU ablations of the liver
Authors: Holbrook Andrew B. , Santos Juan M. , Kaye Elena , Rieke Viola , Pauly Kim Butts
Published: November 2009

A high‐resolution and high‐speed pulse sequence is presented for monitoring high‐intensity focused ultrasound ablations in the liver in the presence of motion. The sequence utilizes polynomial‐order phase saturation bands to perform outer volume suppression, followed by spatial‐spectral excitation and three readout segmented echo‐planar imaging interleaves. Images are processed with referenceless thermometry to create temperature‐rise images every frame. The sequence and reconstruction were implemented in RTHawk and used to image stationary and moving sonications in a polyacrylamide gel phantom (62.4 acoustic W, 50 sec, 550 kHz). Temperature‐rise images were compared between moving and stationary experiments. Heating spots and corresponding temperature‐rise plots matched very well. The stationary sonication had a temperature standard deviation of 0.15° C compared to values of 0.28° C and 0.43° C measured for two manually moved sonications at different velocities. Moving the phantom (while not heating) with respect to the transducer did not cause false temperature rises, despite susceptibility changes. The system was tested on nonheated livers of five normal volunteers. The mean temperature rise was − 0.05° C, with a standard deviation of 1.48° C. This standard deviation is acceptable for monitoring high‐intensity focused ultrasound ablations, suggesting real‐time imaging of moving high‐intensity focused ultrasound sonications can be clinically possible. Magn Reson Med, 2010. © 2009 Wiley‐Liss, Inc.
Longitudinal MRI and MRSI characterization of the quinolinic acid rat model for excitotoxicity: peculiar apparent diffusion coefficients and recovery of N‐acetyl aspartate levels
Authors: Shemesh Noam , Sadan Ofer , Melamed Eldad , Offen Daniel , Cohen Yoram
Published: November 2009

Quinolinic acid (QA) induced striatal lesion is an important model for excitotoxicity that is also used for efficacy studies. To date, the morphological and spectroscopic indices of this model have not been studied longitudinally by MRI; therefore the objectives of this study were aimed at following the lesion progression and changes in N‐acetyl aspartate (NAA) as viewed by MRI and MRSI, respectively, in‐vivo over a period of 49 days. We found that the affected areas exhibited both high and low apparent diffusion coefficients (ADC) even 49 days post QA injection in three of the six tested animals. MRI‐guided histological analysis correlated areas characterized by high ADCs on day 49 with cellular loss, while areas characterized by lower ADCs were correlated with macrophage infiltration (CD68 positive stain). Our MRSI study revealed an initial reduction of NAA levels in the lesioned striatum, which significantly recovered with time, although not to control levels. Total‐striatum normalized NAA levels recovered from 0.67 ± 0.15 (of the contralateral row) on day 1 to 0.90 ± 0.12 on day 49. Our findings suggest that NAA should be considered as a marker for neuronal dysfunction, in addition to neuronal viability. Some behavioral indices could be correlated to permanent neuronal damage while others demonstrated a spontaneous recovery parallel to the NAA recovery. Our findings may have implications in efficacy‐oriented studies performed on the QA model. Copyright © 2009 John Wiley & Sons, Ltd.
Do some enterprise zones create jobs?
Authors: Kolko Jed , Neumark David
Published: November 2009

We study how the employment effects of enterprise zones vary with their location, implementation, and administration, based on evidence from California. We use new establishment‐level data and geographic mapping methods, coupled with a survey of enterprise zone administrators. Overall, the evidence indicates that enterprise zones do not increase employment. However, the evidence also suggests that the enterprise zone program has a more favorable effect on employment in zones that have a lower share of manufacturing and in zones where managers report doing more marketing and outreach activities. On the other hand, devoting more effort to helping firms get hiring tax credits reduces or eliminates any positive employment effects, which may be attributable to idiosyncrasies of California's enterprise zone program during the period we study. © 2010 by the Association for Public Policy Analysis and Management.
Spillover effects of inclusion of classmates with emotional problems on test scores in early elementary school
Authors: Fletcher Jason
Published: November 2009

Over the last decade, the federal government has directed schools to provide educational instruction for students with special needs in general education settings to the extent possible. While there is mixed evidence on the effects of these inclusion policies on the students with special needs, research examining potential spillovers of inclusion on non‐disabled classmates has been scarce. There is particularly little research on the effects of inclusion policies on classmates during early elementary grades. This paper begins to fill in this gap by using a nationally representative, longitudinal survey of kindergartners. Cross‐sectional results suggest that having a classmate with an emotional problem decreases reading and math scores at the end of kindergarten and first grade by over 10 percent of a standard deviation, which is one‐third to one‐half of the minority test score gap. To control for nonrandom sorting of students to schools, as well as students to classrooms, this paper uses school‐level and then student‐level fixed effects. Results from the preferred empirical models suggest a decrease of approximately 5 percent of a standard deviation in math and reading scores, though the reading results are less robust. The results also indicate moderate racial and gender differences in the effects. © 2010 by the Association for Public Policy Analysis and Management.
The impact of the Texas top ten percent law on college enrollment: A regression discontinuity approach
Authors: Niu Sunny Xinchun , Tienda Marta
Published: November 2009

We use regression discontinuity methods on a representative survey of Texas high school seniors to discern the impact on flagship‐enrollment behavior of the Texas top 10 percent law, which guarantees admission to any Texas public university to students who graduate in the top decile of their class. By comparing students at and immediately below the cut‐point for automatic admission, we find that the top 10 percent law affects flagship enrollment of Hispanic students eligible for the admission guarantee, as well as rank‐eligible graduates from high schools where minority students predominate and from high schools with the state average share of economically disadvantaged students. Our findings are robust to various model specifications and different bandwidth choices using local linear estimation. © 2010 by the Association for Public Policy Analysis and Management.
Does inconvenience explain low take‐up? Evidence from unemployment insurance
Authors: Ebenstein Avraham , Stange Kevin
Published: November 2009

Application inconvenience is one popular explanation for why many individuals do not receive the social benefits for which they are eligible. Applications take time and some individuals may decide that the financial benefits do not outweigh these time costs. This paper investigates this explanation using cross‐state variation in administrative changes that made applying for unemployment insurance (UI) benefits substantially more convenient over the past decade. We find that the introduction of phone‐ and Internet‐based claiming did not have an appreciable impact on overall UI take‐up, nor did it lead to a shift toward recipients that are higher income or likely to be receiving the maximum benefit amount. These findings are inconsistent with a time‐ and transaction‐cost explanation for low take‐up, since remote UI claiming is less time intensive. This suggests that reducing application barriers alone may not be an effective tool for increasing program participation. © 2010 by the Association for Public Policy Analysis and Management.
Information disclosure policy: Do state data processing efforts help more than the information disclosure itself?
Authors: Bae Hyunhoe , Wilcoxen Peter , Popp David
Published: November 2009

The Toxics Release Inventory (TRI) was expected to reduce health risks stemming from emissions of hazardous chemicals by increasing public pressure on polluters. However, raw TRI data fails to transmit accurate information fitted to the public's interest. TRI is a massive and complex data set that, in its raw form, provides information on the pounds of toxics released, rather than the risks these releases pose to human health, which is the true quantity of interest. Consequently, raw TRI data needs to be refined and interpreted in terms of health risks by its users, which requires analytical sophistication and substantial data processing. State governments have attempted to increase of the usefulness of the TRI to the general public via two types of policies: (1) selection and dissemination of raw TRI data for plants within the state, and (2) data processing activities producing more refined reports and further data analysis. This study assesses the effectiveness of those two policies, asking how much each contributes to the intended policy outcome of reducing health risks. Our results show that state‐level data dissemination efforts lowered the total number of pounds of chemicals released, but had little effect on health risks. State‐level data processing efforts, in contrast, did lead to significant reductions in health risks. We conclude that simple dissemination of the data was ineffective (and even counterproductive in some instances), and that the states' data processing efforts have played a critical role in achieving the TRI's intended policy goal by providing better information to end users. © 2010 by the Association for Public Policy Analysis and Management.
Incentives and their dynamics in public sector performance management systems
Authors: Heinrich Carolyn J. , Marschke Gerald
Published: November 2009

We use the principal‐agent model as a focal theoretical frame for synthesizing what we know, both theoretically and empirically, about the design and dynamics of the implementation of performance management systems in the public sector. In this context, we review the growing body of evidence about how performance measurement and incentive systems function in practice and how individuals and organizations respond and adapt to them over time, drawing primarily on examples from performance measurement systems in public education and social welfare programs. We also describe a dynamic framework for performance measurement systems that takes into account strategic behavior of individuals over time, learning about production functions and individual responses, accountability pressures, and the use of information about the relationship of measured performance to value added. Implications are discussed and recommendations derived for improving public sector performance measurement systems. © 2010 by the Association for Public Policy Analysis and Management.
A study on the micro‐injection molding of multi‐cavity ultra‐thin parts
Authors: Yang S.‐Y. , Nian S.‐C. , Huang S.‐T. , Weng Y.‐J.
Published: November 2009

In this study, we report the micro‐injection molding of ultra‐thin parts (100, 250, and 500 µm). The results show that the flow resistance increases as the cavity becomes thinner. The melt front is not symmetric when filling a four‐cavity ultra‐thin part and filling the eight‐cavity mold under a low temperature. If we increase the mold temperature or cavity thickness, the melt front becomes symmetric. Finally, we construct the operation windows of molding for three kinds of plastics (PS, PMMA, PC) and provide a molding range based on mold temperature and injections speed. Meanwhile, the relationship between the thickness and the operation windows are also investigated. The thinner the cavity is, the smaller the operation window is. We need to increase the injection speed significantly for molding the ultra‐thin parts with micro‐features on both surfaces which are 60 µm in thickness. Furthermore, we succeed in molding 30 µm ultra‐thin parts in this experiment. Copyright © 2009 John Wiley & Sons, Ltd.
The morphology and structure of PS‐b‐P4VP block copolymer films by solvent annealing: effect of the solvent parameter
Authors: O'Driscoll Sheena , Demirel G , Farrell Richard A. , Fitzgerald Thomas G. , O'Mahony Colm , Holmes Justin D. , Morris Michael A.
Published: November 2009

Lamellae (symmetric) forming polystyrene‐b‐poly(4‐vinylpyridine) (PS‐b‐P4VP) block copolymers (BCPs) were used to produce nanostructured thin films by solvent (toluene) casting (spin‐coating) onto silicon substrates. As expected, strong micellization of PS‐P4VP in toluene results in poorly ordered hexagonally structures films. Following deposition the films were solvent annealed in various solvents and mixtures thereof. A range of both morphologies including micelle and microphase separated structures were observed. It was found that nanostructures typical of films of regular thickness (across the substrate) and demonstrating microphase separation occurred only for relatively few solvents and mixtures. The data demonstrate that simple models of solvent annealing based on swelling of the polymer promoting higher polymer chain mobility are not appropriate and more careful rationalization is required to understand these data. Analysis suggests that regular phase separated films can only be achieved when the copolymer Hildebrand solubility parameter is very similar to the value of the solvent. It is suggested that the solvent anneal method used is best considered as a liquid phase technique rather than a vapor phase method. The results show that solvent annealing methods can be a very powerful means to control structure and in some circumstances dominate other factors such as surface chemistry and surface energies. Copyright © 2009 John Wiley & Sons, Ltd.
Splenic marginal zone lymphoma: characterization of 7q deletion and its value in diagnosis
Authors: Watkins A James , Huang Yuanxue , Ye Hongtao , Chanudet Estelle , Johnson Nicola , Hamoudi Rifat , Liu Hongxiang , Dong Gehong , Attygalle Ayoma , McPhail Ellen D , Law Mark E , Isaacson Peter G , de Leval Laurence , Wotherspoon Andrew , Du Ming‐Qing
Published: November 2009

The diagnosis of splenic marginal zone lymphoma (SMZL) is frequently a challenge, due to its lack of specific histological features and immunophenotypic markers, and the existence of other poorly characterized splenic lymphomas defying classification. Moreover, the clinical outcome of SMZL is variable, with 30% of cases pursuing an aggressive clinical course, the prediction of which remains problematic. Thus, there is a real need for biomarkers in the diagnosis and prognostication of SMZL. To search for genetic markers, we comprehensively investigated the genomic profile, TP53 abnormalities, and immunoglobulin heavy gene (IGH) mutation in a large cohort of SMZLs. 1 Mb resolution array comparative genomic hybridization (aCGH) on 25 SMZLs identified 7q32 deletion (44%) as the most frequent copy number change, followed by gains of 3q (32%), 8q (20%), 9q34 (20%), 12q23–24 (8%), and chromosome 18 (12%), and losses of 6q (16%), 8p (12%), and 17p (8%). High‐resolution chromosome 7 tile‐path aCGH on 17 SMZLs with 7q32 deletion identified by 1 Mb aCGH or interphase FISH screening mapped the minimal common deletion to a 3 Mb region at 7q32.1–32.2. Although it is not yet possible to identify the genes targeted by the deletion, interphase FISH screening showed that the deletion was seen in SMZL (19/56 = 34%) and splenic B‐cell lymphoma/leukaemia unclassifiable (3/9 = 33%), but not in 39 cases of other splenic lymphomas including chronic lymphocytic leukaemia (n = 14), hairy cell leukaemia (4), mantle cell lymphoma (12), follicular lymphoma (6), and others. In SMZL, 7q32 deletion was inversely correlated with trisomy 18, but not associated with other copy number changes, TP53 abnormalities, or IGH mutation status. None of the genetic parameters examined showed significant and independent association with overall or event‐free survival. In conclusion, 7q32 deletion is a characteristic feature of SMZL, albeit seen in isolated cases of splenic B‐cell lymphoma/leukaemia unclassifiable, and its detection may help the differential diagnosis of splenic B‐cell lymphomas. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Selective blockade of endothelial NF‐κB pathway differentially affects systemic inflammation and multiple organ dysfunction and injury in septic mice
Authors: Xu Honglei , Ye Xiaobing , Steinberg Harry , Liu Shu Fang
Published: November 2009

Endothelium has long been considered both a source and a target of systemic inflammation. However, to what extent endothelial activation contributes to systemic inflammation remains unclear. This study addresses the relative contribution of endothelial activation to systemic inflammation and multiple organ dysfunction and injury (MOD/I) in anE. coliperitonitis model of sepsis. We prevented endothelial activation using transgenic (TG) mice that conditionally overexpress a mutant I‐κBα, a NF‐κB inhibitor, selectively on endothelium. TG mice and their transgene negative littermates (WT) were injected with saline orE. coli(108CFU per mouse). At 7 h afterE. coliinfection, markers of systemic inflammation, endothelial activation, and MOD/I were assessed. WT‐E. colimice showed significantly increased serum levels of TNF‐α, IL‐1β, IFN‐γ, IL‐6, KC, and MCP‐1; tissue levels of TNF‐α, IL‐6, KC, MCP‐1, ICAM‐1, and VCAM‐1; endothelial leakage index in heart, lungs, liver, and kidney; significantly increased serum levels of AST, ALT, BUN, and creatinine; and increased mortality. Blockade of NF‐κB‐mediated endothelial activation in TG mice had no effects on serum levels of TNF‐α, IL‐1β, IFN‐γ, IL‐6, KC, and MCP‐1 (markers of systemic inflammation), and tissue levels of TNF‐α, IL‐6, KC, and MCP‐1, but significantly reduced tissue levels of ICAM‐1 and VCAM‐1 (markers of endothelial inflammation and activation) in those four organs. TG‐E. colimice displayed reversed endothelial leakage index; reduced serum levels of AST, ALT, BUN, and creatinine; and improved survival. Our data demonstrate that endothelial NF‐κB‐driven inflammatory response contributes minimally to systemic inflammation, but plays a pivotal role in septic MOD/I, suggesting that endothelium is mainly a target rather than a source of systemic inflammation. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Differential expression of interleukin‐17 family cytokines in intact and complicated human atherosclerotic plaques
Authors: de Boer Onno J , van der Meer Jelger J , Teeling Peter , van der Loos Chris M , Idu Mirza M , van Maldegem Febe , Aten Jan , van der Wal Allard C
Published: November 2009

In addition to the classical TH1 and TH2 cytokines, members of the recently identified IL‐17 cytokine family play an important role in regulating cellular and humoral immune responses. At present nothing is known about the role of these cytokines in atherosclerosis. Expression of IL‐17A, ‐E and ‐F was investigated in atherosclerotic tissue by rtPCR and immunohistochemistry. IL‐17E and its receptor were further studied in cultured smooth muscle cells and endothelial cells, using rtPCR and western blot. rtPCR showed that IL‐17A, ‐E and ‐F were expressed in the majority of plaques under investigation. IL‐17A/F was expressed by mast cells in all stages of plaque development. IL‐17A/F+ neutrophils were always observed in complicated plaques, but hardly in intact lesions. IL‐17A/F+ Tcells (‘TH17’) were never observed. IL‐17E was expressed by smooth muscle cells and endothelial cells in both normal and atherosclerotic arteries, and in advanced plaques also extensively by mature B cells. Cultured smooth muscle cells and endothelial cells were found to express both IL‐17E and its functional receptor (IL‐17RB). The constitutive expression of IL‐17E by resident plaque cells, and the additional presence of IL‐17E+ B cells and IL‐17A/F+ neutrophils in advanced and complicated plaques indicates a complex contribution of IL‐17 family cytokines in human atherosclerosis, depending on the stage and activity of the disease. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Gestational age‐related reference values for amniotic fluid organic acids
Authors: Ottolenghi C. , Abermil N. , Lescoat A. , Aupetit J. , Beaugendre O. , Morichon‐Delvallez N. , Ricquier D. , Chadefaux‐Vekemans B. , Rabier D.
Published: November 2009

Background

Normative data for amniotic fluid (AF) levels of organic acids at different gestational ages are lacking. They can provide a useful framework to investigate the accuracy of prenatal diagnosis for organic acidemias.

Methods

We report on the concentration of 21 organic acids in AF obtained by gas chromatography/mass spectrometry between the 12th and 34th weeks of gestation from 92 pregnancies that were not at risk for organic acidurias.

Results

We infer normal reference values that can be compared with 134 pregnancies at risk for several metabolic conditions, that is, propionic acidemia, methylmalonic acidemia (methylmalonyl‐CoA mutase deficiency or defects in cobalamin metabolism), 4‐hydroxybutyric acidemia, glutaric acidemia and pyroglutamic acidemia.

Conclusion

Most of the metabolites tested did not show conspicuous variations across gestational ages in normal fetuses, with ranges that were consistently similar to available reference values from pooled samples in previous reports. With rare exceptions, knowledge of pathological versus normal values for relevant metabolites leads to clear‐cut differentiation of affected versus unaffected fetuses. Nevertheless, it is strongly recommended that mutational analysis and/or additional biochemical approaches complement organic acid analysis for an adequate diagnostic workup. Copyright © 2009 John Wiley & Sons, Ltd.
Structure, electrical and optical properties of (PVA/LiAsF6) polymer composite electrolyte films
Authors: Varishetty Madhu Mohan , Qiu Weiliang , Gao Yuan , Chen Wen
Published: November 2009

In this work, Li+ ion conducting polymer composite electrolyte films (PECs) were prepared based on poly (vinyl alcohol) (PVA), lithium hexafluoro arsenate (LiAsF6), and ceramic filler TiO2 using solution cast technique. The XRD and FTIR spectra were used to determine the complexation of the PVA polymer with LiAsF6 salt. The ionic conductivities of the (PVA + LiAsF6) and (PVA + LiAsF6 + TiO2) films have been determined by the A.C. impedance measurements in the temperature range 320–440 K. The maximum conductivity was found to be 5.10 × 10−4 S cm−1 for PVA:LiAsF6 (75:25) + 5 wt% TiO2 polymer composite film at 320 K. The calculation of Li+ ion transference number was carried out by the combination of A.C. impedance and D.C. polarization methods and is found to be 0.52 for PVA:LiAsF6 (75:25) + 5 wt% TiO2 film. Optical properties such as direct energy gap, indirect energy gap, and optical absorption edge values were investigated in pure PVA and salt complexed PVA films from their optical absorption spectra in the wavelength range of 200–600 nm. The absorption edge was found at 5.76 eV for undoped film, while it is observed at 4.87 and 4.70 eV for 20 and 25 wt% LiAsF6 doped films, respectively. The direct band gaps for these undoped and salt doped PVA films were found to be 5.40, 5.12, and 4.87 eV, respectively, whereas the indirect band gaps were determined as 4.75, 4.45, and 4.30 eV. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
On the physical behavior of isotactic polypropylene fibers extruded at different draw‐down ratios: II. Structure and properties
Authors: El‐Dessouky Hassan M. , Mahmoudi Mohammad R. , Lawrence Carl A. , Lewis Eric L.V. , Voice Alison M. , Ward Ian M.
Published: November 2009

Microinterferometry (MIF), wide‐angle X‐ray scattering (WAXS), differential scanning calorimetry (DSC), and an Instron tensile tester (ITT) were used to determine the correlation between optical and structural properties of polypropylene (PP) fibers. For the purpose of the study a set of as‐spun isotactic PP fibers were extruded by melt spinning at different draw‐down ratios (DDR). The birefringence (Δn), degrees of orientation, degree of crystallinity (χ), Young's modulus (Ee), and tenacity (τ) were determined for PP fibers at the different DDR. An equiangular orientation of PP fibers at particular DDR was predicted experimentally, and the transverse modulus (Et) was estimated for the tested fibers. Empirical formulae were developed for correlating the fiber birefringence with some of the studied structural properties of PP fibers. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Effect of processing parameters, antistiction coatings, and polymer type when injection molding microfeatures
Authors: Yoon Sung‐Hwan , Cha Nam‐Goo , Lee Jun S. , Park Jin‐Goo , Carter David J. , Mead Joey L. , Barry Carol M.F.
Published: November 2009

Thermoplastic polyurethane (TPU) and silicon tooling with microscale features on its surface was employed to investigate the impact of three factors on the quality of injection molded microscale features: (1) optimized process parameters, (2) use of a more flexible thermoplastic material, and (3) used as an antistiction coating. The molded parts and tooling surface were characterized by atomic force, confocal, and scanning electron microscopy. Although both improved filling of the tooling trenches, higher mold temperatures significantly enhanced replication, but faster injection velocities contributed moderately to replication quality. With medium aspect ratio (2.3:1) trenches, the antistiction coating doubled depth ratios, enhanced the edge definition and flatness of the features, and significantly reduced tearing of the features during ejection. The flexibility of the TPU permitted easier part ejection and left less polymer residue on the tooling surface in comparison to polycarbonate and other thermoplastic polymers. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Influence of Ca[(Li1/3Nb2/3)0.8Ti0.2]O3‐δ filler on the microwave dielectric properties of polyethylene and polystyrene for microelectronic applications
Authors: George Sumesh , Deepu Vasudevan Nair , Mohanan Pezholil , Sebastian Mailadil Thomas
Published: November 2009

Ceramic reinforced polyethylene and polystyrene composites were prepared by melt mixing and hot molding techniques. Temperature stable low‐loss Ca[(Li1/3Nb2/3)0.8Ti0.2]O3‐δ (CLNT) ceramic was used as the filler to improve the dielectric properties of the polymers. The relative permittivity and dielectric loss in the microwave frequency range were increased with increase in the ceramic loading. As the filler content increased from 0 to 0.50 volume fraction, the relative permittivity increased from 2.3 to 9 and dielectric loss tangent from 0.0006 to 0.005 for polyethylene‐CLNT composite. In the case of polystyrene‐CLNT composite, the relative permittivity and dielectric loss tangent increased from 2.1 to 10.5 and 0.0005 to 0.0032 respectively with increase in filler content from 0 to 0.50 volume fractions. The thermal stability of the relative permittivity of polymer ceramic composites was also investigated. The experimentally observed relative permittivity was compared with theoretical models. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Terpolymerization kinetics of N,N‐dimethylaminoethyl methacrylate/alkyl methacrylate/styrene systems
Authors: Šoljić Ivana , Jukić Ante , Janović Zvonimir
Published: November 2009

Low conversion kinetics of terpolymerization of N,N‐dimethylaminoethyl methacrylate (DMAEM) and dodecyl methacrylate (DDMA) with methyl methacrylate (MMA) or styrene (ST) was investigated. Reactions were performed at 70°C, in toluene solutions, using peroxide initiator. The interdependence between terpolymer and monomer feed composition was successfully described by Alfrey‐Goldfinger equation and the unitary, binary, and ternary azeotropes were calculated. In MMA‐containing system, the wide pseudoazeotropic region with existence of true azeotropic point was observed and experimentally confirmed at the DMAEM:MMA:DDMA molar ratio of 56:41:3. In the ST‐containing system compositional heterogeneity was significant, more than 10 mol%. Required copolymerization reactivity ratios were determined by linear and nonlinear methods. The glass transition temperatures of synthesized terpolymers are found to be between those of the corresponding homopolymers and relative to their content. Increase in the MMA or ST contents and decrease in the DDMA content in terpolymers results in an increase in their glass transition temperatures. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Effects of coagulation bath temperature and polyvinylpyrrolidone content on flat sheet asymmetric polyethersulfone membranes
Authors: Amirilargani M. , Saljoughi E. , Mohammadi T. , Moghbeli M.R.
Published: November 2009

In this study, effects of coagulation bath temperature (CBT) and polyvinylpyrrolidone (PVP K15) concentration as a pore former hydrophilic additive on morphology and performance of asymmetric polyethersulfone (PES) membranes were investigated. The membranes were prepared from a PES/ethanol/NMP system via phase inversion induced by immersion precipitation in a water coagulation bath. The morphology of prepared membranes was studied by scanning electron microscopy (SEM), contact angle measurements, and mechanical property measurements. Permeation performance of the prepared membranes was studied by separation experiments using pure water and bovine serum albumin (BSA) solution as feed. The obtained results indicate that addition of PVP in the casting solution enhances pure water permeation flux and BSA solution permeation flux while reducing protein rejection. Increasing CBT results in macrovoid formation in the membrane structure and increases the membrane permeability and decreases the protein rejection. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Preparation and properties of HDPE/CaCO3/OMMT ternary nanocomposite
Authors: Dai Xin , Shang Qingkun , Jia Qiong , Li Shichun , Xiu Yanhua
Published: November 2009

A series of binary composites based on HDPE (high density polyethylene) and nanoinorganic particles such as nano‐CaCO3 and OMMT (organic montmorillonite) were prepared. Their properties including tensile, impact strength, and some thermal properties were tested. The results showed that binary composite has partial improvement in mechanical properties compared with pure HDPE. A ternary composite nano‐CaCO3/OMMT/HDPE was prepared and characterized. It was found that the mechanical and thermodynamic properties of this ternary composite have been enhanced greatly compared with both pure HDPE and binary composites. The tensile strength, Young's modulus, flexural strength, elastic modulus, and impact strength of nano‐CaCO3/OMMT/HDPE were increased 124.6%, 302.7%, 73.86%, 58.97%, and 27.25%, respectively. The DMA test results showed that the mechanical properties of ternary composite were increased because of the limitation on the movement of HDPE due to inorganic particles. The synergistic effect introduced by nanoparticles may play an important role in all these processes. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Financial Incentives and Advanced Construction Procurement Systems
Authors: Rose Timothy M. , Manley Karen
Published: November 2009

Construction clients often use financial incentives to encourage stakeholder motivation and commitment to voluntary higher-order project goals. Despite the increased use of financial incentives, there is little literature addressing means of optimizing outcomes. Using a case-study methodology, the examination of a successful Australian construction project demonstrates the features of a positively geared procurement approach that promotes the effectiveness of financial incentives. The research results show that if the incentive system is perceived to be fair and is applied to reward exceptional performance, and not to manipulate, then contractors are more likely to be positively motivated.
Novel antimicrobial peptides identified from an endoparasitic wasp cDNA library
Authors: Shen Xiaojing , Ye Gongyin , Cheng Xiongying , Yu Chunyan , Yao Hongwei , Hu Cui
Published: November 2009

We screened an endoparasitic wasp (Pteromalus puparum) cDNA library for DNA sequences having antimicrobial activity using a vital dye exclusion assay. Two dozens of clones were isolated that inhibited the growth of host Escherichia coli cells due to expression of the cloned genes. Three peptides (PP13, PP102 and PP113) were synthesized chemically based on the amino acid sequences deduced from these clones and assayed for their antimicrobial activity. These peptides have net positive charges and are active against both Gram‐negative and ‐positive bacteria, but are not active against fungi tested. Their hemolytic activity on human red blood cells was measured, and no hemolytic activity was observed after 1‐h incubation at a concentration of 62.5 µM or below. A Blast search indicated that the three peptides have not been previously characterized as antimicrobial peptides (AMPs). Salt‐dependency studies revealed that the biocidal activity of these peptides against E. coli decreased with increasing concentration of NaCl. Transmission electron microscopic (TEM) examination of PP13‐treated E. coli cells showed extensive damage of cell membranes. The CD spectroscopy studies noted that the enhanced α‐helical characteristics of PP13 strongly contribute to its higher antimicrobial properties. These results demonstrate the feasibility to identify novel AMPs by screening the expressional cDNA library. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.
Azide reduction during peptide cleavage from solid support—the choice of thioscavenger?
Authors: Schneggenburger Philipp E. , Worbs Brigitte , Diederichsen Ulf
Published: November 2009

Peptide azides acquired growing impact because of application in bioconjugation via ‘click chemistry’ or Staudinger ligation. Furthermore, there are many methods established in organic synthesis addressing the reduction of azides to amines, but no observation of a reductive transformation of peptide azides during SPPS cleavage was yet reported. In the present study, the reduction of peptide azides during SPPS cleavage was investigated depending on the choice of thioscavenger, reacting as reductive species. First observed for short PNA/peptide conjugates the occurring extensive side reaction was also validated for one of the applied azide amino acid building blocks and was further investigated by applying different cleavage cocktails to a series of peptides varying in hydrophobicity and position of the azide moiety in the oligomer sequence. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.
COMU: A third generation of uronium‐type coupling reagents
Authors: El‐Faham Ayman , Albericio Fernando
Published: November 2009

COMU is a third generation of uronium‐type coupling reagent based on ethyl 2‐cyano‐2‐(hydroxyimino)acetate (Oxyma) as well as a morpholino carbon skeleton. The presence of the morpholino group has a marked influence on the solubility, stability and reactivity of the reagent. COMU performed extremely well in the presence of only 1 equiv. of base, thereby confirming the effect of the hydrogen bond acceptor in the reaction. The by‐products of COMU are water soluble and easily removed, making it an excellent choice of coupling reagent for solution‐phase peptide synthesis. Finally, COMU shows a less hazardous safety profile than benzotriazole‐based reagents, such as HATU and HBTU, which in addition exhibit unpredictable autocatalytic decompositions and therefore a higher risk of explosion. Furthermore, in contrast to benzotriazole‐based reagents, COMU is significantly less likely to cause allergic reaction. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.