bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation using an HER‐2/neu transgenic mouse model of a newly developed MR contrast agent with the effect of an antitumor drug
Authors: Sonoda Akinaga , Nitta Norihisa , Ohta Shinich , Nitta‐Seko Ayumi , Murata Satoshi , Jo Jun‐ichiro , Tabata Yasuhiko , Takahashi Masashi , Tani Toru , Murata Kiyoshi
Published: September 2009

Purpose

To assess whether Gd‐DTPA‐Gel‐Cis, a conjugate of gadolinium (Gd), cis diamminedichloroplatinum (Cis), diethylenetriaminepentaacetic acid (DTPA)‐dianhydride, and bovine gelatin (Gel) can be used as an intravascular contrast agent at MRI and as an antitumor cell proliferation agent in vitro.

Materials and Methods

We injected Gd‐DTPA‐Gel‐Cis (200 mg/mL) into the caudal vein of female HER‐2/neu transgenic mice with spontaneous mammary tumors. The tumor signal intensity was measured with a 0.3 Tesla MRI scanner. HER‐2/neu‐expressing NT cells were treated with Gd‐DTPA‐Gel‐Cis (5 μM cisplatin, 200 mg/mL Gel), Cis alone (5 μM cisplatin), or Gel alone (200 mg/mL gelatin). Differences of P < 0.05 were considered to be statistically significant.

Results

On T1‐weighted MRI scans of mice injected with Gd‐DTPA‐Gel‐Cis we observed a 23% increase in signal intensity. The survival rates of cells exposed to Gd‐DTPA‐Gel‐Cis or Cis were 70.9% and 58.3%, respectively, of the survival rates observed after treatment with Gel alone. Gd‐DTPA‐Gel‐Cis showed significant toxicity (P < 0.05).

Conclusion

Gd‐DTPA‐Gel‐Cis shows promise for use as an MRI contrast medium and as an antitumor agent. J. Magn. Reson. Imaging 2009;30:907–910. © 2009 Wiley‐Liss, Inc.
Effects of diffusion time on short‐range hyperpolarized 3He diffusivity measurements in emphysema
Authors: Gierada David S. , Woods Jason C. , Bierhals Andrew J. , Bartel Seth T. , Ritter Jon H. , Choong Cliff K. , Das Nitin A. , Hong Cheng , Pilgram Thomas K. , Chang Yulin V. , Jacob Richard E. , Hogg James C. , Battafarano Richard J. , Cooper Joel D. , Meyers Bryan F. , Patterson G. Alexander , Yablonskiy Dmitriy A. , Conradi Mark S.
Published: September 2009

Purpose

To characterize the effect of diffusion time on short‐range hyperpolarized 3He magnetic resonance imaging (MRI) diffusion measurements across a wide range of emphysema severity.

Materials and Methods

3He diffusion MRI was performed on 19 lungs or lobes resected from 18 subjects with varying degrees of emphysema using three diffusion times (1.6 msec, 5 msec, and 10 msec) at constant b value. Emphysema severity was quantified as the mean apparent diffusion coefficient (ADC) and as the percentage of pixels with ADC higher than multiple thresholds from 0.30–0.55 cm2/sec (ADC index). Quantitative histology (mean linear intercept) was obtained in 10 of the lung specimens from 10 of the subjects.

Results

The mean ADCs with diffusion times of 1.6, 5.0, and 10.0 msec were 0.46, 0.40, and 0.37 cm2/sec, respectively (P < 0.0001, analysis of variance [ANOVA]). There was no relationship between the ADC magnitude and the effect of diffusion time on ADC values. The mean linear intercept correlated with ADC (r = 0.91–0.94, P < 0.001) and ADC index (r = 0.78–0.92, P < 0.01) at all diffusion times.

Conclusion

Decreases in ADC with longer diffusion time were unrelated to emphysema severity. The strong correlations between the ADC at all diffusion times tested and quantitative histology demonstrate that ADC is a robust measure of emphysema. J. Magn. Reson. Imaging 2009;30:801–808. © 2009 Wiley‐Liss, Inc.
Algorithm‐based method for detection of blood vessels in breast MRI for development of computer‐aided diagnosis
Authors: Lin Muqing , Chen Jeon‐Hor , Nie Ke , Chang Daniel , Nalcioglu Orhan , Su Min‐Ying
Published: September 2009

Purpose

To develop a computer‐based algorithm for detecting blood vessels that appear in breast dynamic contrast‐enhanced (DCE) magnetic resonance imaging (MRI), and to evaluate the improvement in reducing the number of vascular pixels that are labeled by computer‐aided diagnosis (CAD) systems as being suspicious of malignancy.

Materials and Methods

The analysis was performed in 34 cases. The algorithm applied a filter bank based on wavelet transform and the Hessian matrix to detect linear structures as blood vessels on a two‐dimensional maximum intensity projection (MIP). The vessels running perpendicular to the MIP plane were then detected based on the connectivity of enhanced pixels above a threshold. The nonvessel enhancements were determined and excluded based on their morphological properties, including those showing scattered small segment enhancements or nodular or planar clusters. The detected vessels were first converted to a vasculature skeleton by thinning and subsequently compared to the vascular track manually drawn by a radiologist.

Results

When evaluating the performance of the algorithm in identifying vascular tissue, the correct‐detection rate refers to pixels identified by both the algorithm and radiologist, while the incorrect‐detection rate refers to pixels identified by only the algorithm, and the missed‐detection rate refers to pixels identified only by the radiologist. From 34 analyzed cases the median correct‐detection rate was 85.6% (mean 84.9% ± 7.8%), the incorrect‐detection rate was 13.1% (mean 15.1% ± 7.8%), and the missed‐detection rate was 19.2% (mean 21.3% ± 12.8%). When detected vessels were excluded in the hot‐spot color‐coding of the CAD system, they could reduce the labeling of vascular vessels in 2.6%–68.6% of hot‐spot pixels (mean 16.6% ± 15.9%).

Conclusion

The computer algorithm‐based method can detect most large vessels and provide an effective means in reducing the labeling of vascular pixels as suspicious on a DCE‐MRI CAD system. This algorithm may improve the workflow of radiologists using CAD for image display, but will be particularly useful for development of automated CAD that gives diagnostic impression. J. Magn. Reson. Imaging 2009;30:817–824. © 2009 Wiley‐Liss, Inc.
Improved correlation to quantitative DCE‐MRI pharmacokinetic parameters using a modified initial area under the uptake curve (mIAUC) approach
Authors: Cheng Hai‐Ling Margaret
Published: September 2009

Purpose

To propose a modified initial area under the uptake curve (mIAUC) dynamic contrast‐enhanced (DCE)‐MRI approach to achieve better distinction of underlying physiology.

Materials and Methods

The mIAUC is formulated on common characteristics of tissue contrast uptake curves observed over a wide range of physiological conditions. The new metrics, IAUCKtrans and IAUCve, are related to the transfer constant (Ktrans) and interstitial volume (ve), respectively. Tissue uptake curves were simulated over a range of physiological values and analyzed using the proposed mIAUC, conventional IAUC, and Tofts' pharmacokinetic model.

Results

IAUCKtrans and IAUCve are highly correlated to the true Ktrans and ve (ρ = 0.97 and 0.95, respectively), approaching the performance of Tofts' model based on a 1.5‐s sampled arterial input function (AIF) (ρ = 0.98 and 0.98) under noise conditions typical in DCE‐MRI experiments. Lower correlations were obtained with conventional IAUC60 and IAUC120 (ρ = 0.82 and 0.61) and Tofts' parameters fitted using a biexponential AIF (ρ = 0.81 and 0.90).

Conclusion

The proposed mIAUC approach retains advantages associated with nonmodel based methods (robust to noise and model fit failure, obviates need for an AIF) while providing better distinction of underlying physiological parameters. It can be a valuable alternative to pharmacokinetic modelling in the analysis of DCE‐MRI data. J. Magn. Reson. Imaging 2009;30:864–872. © 2009 Wiley‐Liss, Inc.
First‐pass and steady‐state magnetic resonance angiography of the thoracic vasculature using gadofosveset trisodium
Authors: Naehle Claas P. , Müller Andreas , Willinek Winfried A. , Meyer Carsten , Hestermann Tobias , Gieseke Juergen , Schild Hans , Thomas Daniel
Published: September 2009

Purpose

To compare a high‐resolution, ECG‐gated, motion‐compensated, steady‐state magnetic resonance angiography (SS‐MRA) of the thoracic vasculature to standard first‐pass MRA (FP‐MRA) using a blood‐pool contrast agent (gadofosveset trisodium).

Materials and Methods

In all, 25 patients ≥18 years with congenital or acquired disease of the thoracic vasculature, who underwent both FP‐MRA and SS‐MRA, were retrospectively identified. Diameters of left superior pulmonary vein (LSPV), left pulmonary artery (LPA), and aortic arch (AA) were measured. Image quality for LSPV, LPA, AA, coronary ostia, and coronary sinus were assessed. Vessel sharpness of LPA and LSPV and contrast ratio (CR) of LSPV, LPA, and AA were calculated.

Results

SS‐MRA yielded significantly higher image quality for all vessels, and significantly higher vessel sharpness for LSPV and LPA compared to the FP‐MRA. SS‐MRA revealed lower intra‐ and interobserver variability for vessel diameters compared with the FP‐MRA. The FP‐MRA showed higher CR compared to the SS‐MRA.

Conclusion

Motion‐compensated high‐resolution SS‐MRA of the thoracic vasculature using gadofosveset trisodium offers superior image quality compared to standard FP‐MRA. Although SS‐MRA delivers no dynamic information it may prove specifically helpful as an add‐on to FP‐MRA for imaging of small vascular structures. J. Magn. Reson. Imaging 2009;30:809–816. © 2009 Wiley‐Liss, Inc.
Contrast‐enhanced myocardial T1‐weighted scout (Look–Locker) imaging for the detection of myocardial damages in hypertrophic cardiomyopathy
Authors: Amano Yasuo , Takayama Morimasa , Kumita Shinichiro
Published: September 2009

Purpose

To assess the myocardial damage in hypertrophic cardiomyopathy (HCM) using contrast‐enhanced myocardial T1‐weighted scout (Look–Locker) magnetic resonance imaging (MRI).

Materials and Methods

Twenty‐three patients with HCM and seven comparative patients without known HCM serving as controls underwent cine, contrast‐enhanced myocardial T1‐weighted scout and delayed‐enhancement MRI using a 1.5T unit. Intervals of null points between myocardium and blood were compared among hyperenhancing and nullified myocardium of HCM and the normal myocardium. The relationship between these myocardial patterns and global cardiac functions was analyzed in HCM.

Results

The hyperenhancing myocardium, dense myocardial fibrosis in HCM had null points significantly shorter than blood, normal myocardium, and nullified myocardium of HCM (P < 0.0001). The number of hyperenhancing myocardial segments correlated with the ejection fraction (P = 0.045). The nullified myocardium of HCM showed shorter intervals of the null points between myocardium and blood than did the normal myocardium, indicating the dispersed myocardial fibrosis (P = 0.0032). The interval of null points between the nullified myocardium and blood showed a significant correlation with the increase in myocardial mass in HCM (P = 0.034).

Conclusion

Contrast‐enhanced myocardial T1‐weighted scout imaging has the potential for showing dispersed myocardial damage leading to increased myocardial mass in HCM, while the dense myocardial fibrosis correlated with reduced ejection fraction. J. Magn. Reson. Imaging 2009;30:778–784. © 2009 Wiley‐Liss, Inc.
Initial feasibility of a multi‐station high resolution three‐dimensional dark blood angiography protocol for the assessment of peripheral arterial disease
Authors: Mihai Georgeta , Chung Yiu‐Cho , Kariisa Mbabazi , Raman Subha V. , Simonetti Orlando P. , Rajagopalan Sanjay
Published: September 2009

Purpose

To evaluate the feasibility of a multi‐station three dimensional (3D) T1‐weighted turbo spin echo (TSE) dark‐blood Sampling Perfection with Application optimized Contrasts using different flip angle Evolution sequence (T1w‐SPACE), to assess aorta, iliac, and superficial femoral (SFA) arteries (inflow vessels) by comparing it with a multi‐station contrast enhanced MR angiography (CE‐MRA) with identical resolution.

Materials and Methods

A total of 6 volunteers and 14 peripheral arterial disease (PAD) patients were included in the study. Abdominal and thigh T1w‐SPACE and lower leg time‐resolved MRA (TR‐MRA) with low dose contrast were followed by 3‐station CE‐MRA. Quantitative measurements of lumen area at 17 locations from T1w‐SPACE and CE‐MRA were obtained. Additionally, vessel wall areas at the same locations were obtained from the T1w‐SPACE images.

Results

Quantitative comparison of lumen areas with T1w‐SPACE and CE‐MRA revealed strong correlation between the two techniques and strong inter‐observer agreement for each of the two imaging methods (r > 0.9; P < 0.001). Localized vessel wall area measurements obtained in PAD patients were significantly greater compared with those obtained in normal volunteers (mean difference 43.75 ± 12.46 mm2; P < 0.001). Stenosis severity obtained from T1w‐SPACE localized measurements showed significant arterial area stenosis in PAD patients.

Conclusion

T1w‐SPACE imaging of inflow vessels is feasible, and in addition to CE‐MRA has the ability to assess atherosclerotic plaque and vascular remodeling. J. Magn. Reson. Imaging 2009;30:785–793. © 2009 Wiley‐Liss, Inc.
Atypical imaging appearance of toxoplasmosis in an HIV patient as a butterfly lesion
Authors: Chaudhari Vinika V. , Yim Catherine M. , Hathout Heba , Lai Andrew , Donovan Suzanne M.
Published: September 2009

In acquired immunodeficiency syndrome (AIDS) patients, differentiating toxoplasmosis and primary central nervous system (CNS) lymphoma remains a clinical and radiographic dilemma. The presence of butterfly lesions crossing the corpus callosum is customarily used to exclude the possibility of toxoplasmosis. We present an AIDS patient who had Epstein‐Barr virus (EBV) polymerase chain reaction (PCR) ‐positive cerebrospinal fluid studies with a butterfly toxoplasmosis lesion confirmed by multiple methods signifying the importance of including toxoplasmosis in the differential diagnosis of butterfly lesions. J. Magn. Reson. Imaging 2009;30:873–875. © 2009 Wiley‐Liss, Inc.
Use of a novel ionic liquid matrix for MALDI‐MS analysis of glycopeptides and glycans out of total tryptic digests
Authors: Ullmer Roman , Rizzi Andreas M.
Published: September 2009

In this study, we investigated a novel ionic liquid matrix (ILM), namely, the 1,1,3,3‐tetramethylguanidinium salt of 2,4,6‐trihydroxyacetophenone (THAP). This matrix[1,1,3,3‐tetramethylguanidinium 2,4,6‐trihydroxyacetophenone (GTHAP)] turned out to be well suited for the matrix‐assisted laser desorption/ionization mass spectrometric analysis of glycopeptides and glycans, and overcame the well‐known ionization suppression of carbohydrate structures in the presence of peptides. The matrix was evaluated by two different series of experiments, in each case in comparison with the crystalline THAP matrix. In the first set of experiments, mass spectra were taken from unseparated tryptic digests of three glycoproteins taken as model compounds. Even glycopeptides containing short peptide backbones and large carbohydrate moieties gave high signal intensities when using the ILM though they did not appear in the THAP spectra. In the second set of experiments, the total tryptic digests were treated with endoglycosidase PNGase F to cleave off the N‐linked glycans. When using the GTHAP matrix, it was possible to detect the glycans with high intensities in the presence of the tryptic peptides, whereas glycan ionization was completely suppressed when measured with the solid matrix THAP. The extent of metastable decay of glycopeptides was reduced when using the ILM. Altogether, GTHAP proved as a useful ILM particularly being superior to solid matrices in the context of glycosylation analysis. Copyright © 2009 John Wiley & Sons, Ltd.
Improved identification of hordeins by cysteine alkylation with 2‐bromoethylamine, SDS‐PAGE and subsequent in‐gel tryptic digestion
Authors: Řehulková Helena , Marchetti‐Deschmann Martina , Pittenauer Ernst , Allmaier Günter , Řehulka Pavel
Published: September 2009

Proteomic‐based description of varieties of barley (Hordeum vulgare L.) is a very important task especially in the food and brewing industry. This study is focused on major storage proteins in barley—hordeins—as a group of proteins soluble in alcohol/water mixtures that shows up significant changes in proteomic profiles for different varieties of barley. Unusual amino acid composition of hordeins with low numbers of lysine and arginine in combination with high content of proline and glutamine complicates their identification in a common proteomic workflow, because tryptic digestion produces just a few peptides amenable for successful mass spectrometric analysis. To increase the number of cleavage sites, in this work, cysteines in hordeins were chemically modified with 2‐bromoethylamine (BEA) for their conversion into aminoethylcysteines. These mimic lysine residues and are recognized by trypsin as potentional cleavage sites (if not followed by a proline residue) on the C‐terminal side of the modified cysteine. Small extent of side reactions (towards histidine, N‐terminus of the peptide, methionine, and also here the newly discovered reaction towards aminoethylcysteine) during modification with BEA could be observed after a longer period of reaction but this did not hinder the analysis when optimal conditions were used. Application of trypsin for in‐gel digestion of hordeins, previously modified chemically with BEA, provided a higher number of short peptides and their subsequent mass spectrometric analysis resulted in an improved identification of hordeins. This approach can also be used for the analysis of other similar protein groups (e.g. gliadins in wheat) or other cysteines containing proteins having a low number of lysine and arginine residues in their primary structure. Copyright © 2009 John Wiley & Sons, Ltd.
Light beats the spread: “non‐diffracting” beams
Authors: Mazilu M. , Stevenson D.James , Gunn‐Moore F. , Dholakia K.
Published: September 2009

“Non‐diffracting” beams do not spread as they propagate. This property is useful in many areas. Here, the theory, generation, properties, and applications of various “non‐diffracting” beams, including the Bessel beam, Mathieu beam, and Airy beam is reviewed. Applications include imaging, micromanipulation, nonlinear optics, and optical transfection.
The progress towards terahertz quantum cascade lasers on silicon substrates
Authors: Paul D.J.
Published: September 2009

A review is presented of work over the last 10 years which has been aimed at trying to produce a Si‐based THz quantum cascade laser. Potential THz applications and present THz sources will be briefly discussed before the materials issues with the Si/SiGe system is discussed. Waveguide designs and waveguide losses will be presented. Experimental measurements of the non‐radiative lifetimes for intersubband transitions in Si1‐xGexquantum wells will be presented along with theory explaining the important scattering mechanisms which determine the lifetimes. Examples of p‐type Si/SiGe quantum cascade designs with the experimental electroluminescence will be reviewed and examples of n‐type Si‐based designs will be presented. In the conclusion designs and structures will be discussed with the greatest potential to achieve an electrically pumped Si‐based THz laser.
Bacterially induced degradation of aqueous solutions of poly(l‐lysine)‐graft‐poly(ethylene glycol) and poly(l‐lysine)‐graft‐dextran: consequences for their lubrication properties
Authors: Argibay Nicolas , Perrino Chiara , Rimann Markus , Lee Seunghwan , Spencer Nicholas D.
Published: September 2009

Experimental data are presented comparing the degradation in the lubrication behaviour of aqueous solutions of the brush copolymers poly(l‐lysine)‐graft‐poly(ethylene glycol) (PLL‐g‐PEG) and poly(l‐lysine)‐graft‐dextran (PLL‐g‐dex) when aged after exposure to bacterial contamination. While PLL‐g‐PEG solutions appear to be relatively unaffected by bacteria after a storage period of as much as 8 weeks, PLL‐g‐dex solutions exposed to bacteria during preparation lead to as much as a twofold increase in friction coefficient, when used as a lubricant in tribological tests, over an 8 week period when compared to reference data from freshly prepared and tested samples. Solutions prepared under sterile conditions and aged for up to 8 weeks do not appear to be degraded. Further experiments implementing the anti‐bacterial agent sodium azide effectively prevented bacterial colonization and degradation in lubrication behaviour. Copyright © 2009 John Wiley & Sons, Ltd.
The value of assessing weights in multi‐criteria portfolio decision analysis
Authors: Keisler Jeffrey M.
Published: September 2009

Analytic efforts in support of portfolio decisions can be applied with varying levels of intensity. To gain insight about how to match the effort to the situation, we simulate a portfolio of potential projects and compare portfolio performance under a range of analytic strategies. Each project is scored with respect to several attributes in a linear additive value model. Projects are ranked in order of value per unit cost and funded until the budget is exhausted. Assuming these weights and scores are correct, and the funding decisions made this way are optimal, this process is a gold standard against which to compare other decision processes. In particular, a baseline process would fund projects essentially at random, and we may estimate the value added by various decision processes above this worst case as a percentage of the increase arising from the optimal process. We consider several stylized decision rules and combinations of them: using equal weights, picking one attribute at random, assessing weights from a single randomly selected stakeholder. Simulation results are then used to identify which conditions tend to make which types of analytic strategies valuable, and to identify useful hybrid strategies. Copyright © 2009 John Wiley & Sons, Ltd.
On the use of importance information in MCDA problems with criteria measured on the first ordered metric scale
Authors: Podinovski Vladislav V.
Published: September 2009

This paper presents theoretical foundations for the description of preferences in multiple criteria decision analysis models using quantitative estimates of the relative importance of criteria. It is assumed that not only the values of criteria but also the differences of such values are ordered according to the preference of the decision maker. Simple decision rules that define the preference and indifference relations induced by the information about the quantitative importance of such criteria are developed. Copyright © 2009 John Wiley & Sons, Ltd.
Treatment of Primary Vertebral Tumors
Authors: Singh Harshpal , Meyer Scott A. , Jenkins Arthur L.
Published: September 2009

Advances in the treatment of disease and detection through advanced imaging have led to an increase in the discovery of vertebral tumors. Although the majority of symptomatic spinal lesions are metastatic in origin, a significant number of them arise primarily in the spine. These lesions encompass a wide variety of tumor types classified by their cell of origin: bony tumors, cartilaginous tumors, vascular tumors, plasma cell dyscrasias, and tumors that arise from embryonic rests. Further classification of these tumors into malignant or benign subtypes is based on their clinical progression, histopathological evidence of invasiveness, and response to therapy. We provide a brief overview and description of primary tumors as well as treatment paradigms for the individual tumor types. Mt Sinai J Med 76:499–504, 2009. © 2009 Mount Sinai School of Medicine
The Plague of Athens: Epidemiology and Paleopathology
Authors: Littman Robert J.
Published: September 2009

In 430 BC, a plague struck the city of Athens, which was then under siege by Sparta during the Peloponnesian War (431‐404 BC). In the next 3 years, most of the population was infected, and perhaps as many as 75,000 to 100,000 people, 25% of the city's population, died. The Athenian general and historian Thucydides left an eye‐witness account of this plague and a detailed description to allow future generations to identify the disease should it break out again. Because of the importance of Thucydides and Athens in Western history and culture, the Plague of Athens has taken a prominent position in the history of the West for the past 2500 years. Despite Thucydides' careful description, in the past 100 years, scholars and physicians have disagreed about the identification of the disease. Based on clinical symptoms, 2 diagnoses have dominated the modern literature on the Athenian plague: smallpox and typhus. New methodologies, including forensic anthropology, demography, epidemiology, and paleopathogy, including DNA analysis, have shed new light on the problem. Mathematical modeling has allowed the examination of the infection and attack rates and the determination of how long it takes a disease to spread in a city and how long it remains endemic. The highly contagious epidemic exhibited a pustular rash, high fever, and diarrhea. Originating in Ethiopia, it spread throughout the Mediterranean. It spared no segment of the population, including the statesman Pericles. The epidemic broke in early May 430 BC, with another wave in the summer of 428 BC and in the winter of 427‐426 BC, and lasted 4.5 to 5 years. Thucydides portrays a virgin soil epidemic with a high attack rate and an unvarying course in persons of different ages, sexes, and nationalities.

The epidemiological analysis excludes common source diseases and most respiratory diseases. The plague can be limited to either a reservoir diseases (zoonotic or vector‐borne) or one of the respiratory diseases associated with an unusual means of persistence, either environmental/fomite persistence or adaptation to indolent transmission among dispersed rural populations. The first category includes typhus, arboviral diseases, and plague, and the second category includes smallpox. Both measles and explosive streptococcal disease appear to be much less likely candidates.

In 2001, a mass grave was discovered that belonged to the plague years. Ancient microbial typhoid (Salmonella enterica serovar Typhi) DNA was extracted from 3 skeletons. Because typhoid was endemic in the Greek world, it is not the likely cause of this sudden epidemic. Mt Sinai J Med 76:456–467, 2009. © 2009 Mount Sinai School of Medicine
The assignment of storage locations to containers for a container stack
Authors: Wan Yat‐wah , Liu Jiyin , Tsai Pei‐Chun
Published: September 2009

Assigning storage locations to incoming or reshuffled containers is a fundamental problem essential to the operations efficiency of container terminals. The problem is notoriously hard for its combinatorial and dynamic nature. In this article, we minimize the number of reshuffles in assigning storage locations for incoming and reshuffled export containers. For the static problem to empty a given stack without any new container arrival, the optimum reshuffle sequence is identified by an integer program (IP). The integer program captures the evolution of stack configurations as a function of decisions and is of interest by itself. Heuristics based on the integer program are then derived. Their competitiveness in accuracy and time are established by extensive numerical runs comparing them with existing heuristics in literature and in practice as well as with extensions of the existing heuristics. Variants of the IP‐based heuristics are then applied to the dynamic problem with continual retrievals and arrivals of containers. Again, numerical runs confirm that the IP‐based heuristic is competitive. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009
Strategic group membership and nonprofit organization performance
Authors: Marlin Dan , Ritchie William J. , Geiger Scott W.
Published: September 2009

This study analyzed the resource characteristics of a sample of university foundations and identified five distinct strategic groups. We found significant performance differences among them. Specifically, the group that focused most heavily on fundraising activities had the highest financial performance. Also performing well was the group with the highest ratio of contributions to total revenues combined with the highest level of slack. The research and managerial implications of this study's findings are discussed.
Patterns of governance structures in trade associations and unions
Authors: Schnurbein Georg von
Published: September 2009

Most research on the governance of nonprofit organizations concentrates on welfare‐oriented organizations and disregards other types of nonprofits. This article examines the governance structures of trade associations and unions as a special type of nonprofit organization. Analysis is based on a qualitative case study survey of thirty Swiss trade associations. The results distinguish four categories of governance: satellite governance, delegate governance, executive governance, and inner‐circle governance.
Modeling the phase behavior in binary mixtures involving blowing agents and thermoplastic resins
Authors: Arce Pedro F. , Aznar Martín
Published: September 2009

The thermophysical properties of mixtures of thermoplastic resins and blowing agents, together with the knowledge of the solubilities of these components, are the basis for the manufacturing of plastic foams. In this work, the solubilities of blowing agents trichlorofluoromethane, dichlorodifluoromethane, chlorodifluoromehane, and 1,2‐dichloro‐1,1,2,2‐tetrafluoroethane in thermoplastic resins poly(styrene), high density poly(ethylene), low density poly(ethylene), poly(propylene), poly(vinyl chloride), poly(carbonate) and poly(propylene oxide) were modeled by using the Perturbed Chain‐Statistical Associating Fluid Theory (PC‐SAFT) and the Sánchez‐Lacombe equations of state (EoS), fitting a single temperature‐dependent binary interaction parameter. PC‐SAFT is a theoretically based equation of state with three pure component parameters that describe efficiently the thermodynamics of complex systems. Earlier works with this EoS have already predicted the phase coexistence properties of various refrigerants and higher order alkane series compounds, along with their mixtures. The pure component parameters for the blowing agents were obtained by regression of vapor pressure and liquid density data, while the pure component parameters for the thermoplastic resins were obtained by regression of pure liquid PVT data. The parameter estimation was performed by using a modified maximum likelihood method. The solubility results obtained with both EoS have been compared; the results from PC‐SAFT showed a higher accuracy in terms of solubility pressure deviations. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Cure advancement of urethane networks using a sigmoidal chemorheological model
Authors: Teyssandier F. , Love B.J.
Published: September 2009

Archived measurements of urethane rheology undergoing crosslinking at 45, 55, and 65°C were reanalyzed by a sigmoidal mathematical model. The phenomenological sigmoidal model, with two kinetic parameters associated with cure advancement coupled with parameters for the initial viscosity and the terminal viscosity of the network, captures the nonlinearities in dynamic viscosity during polymerization and were similarly compared with a power law model. The interpretation of the gel time was determined using both models, with the sigmoidal model interpretation of the gel time being defined in terms of the other kinetic constants. The takeaway message is that there is very little difference in the quality of the fit between the power law model and the sigmoidal model and the experimental dynamic viscosity data. One would need a more comprehensive dataset to make a larger comparison as to which model actually represents viscosity more accurately. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Novel anionic polyaddition of 2‐trifluoromethylacrylate by double Michael reaction with ethyl cyanoacetate
Authors: Umino Youhei , Nozaki Hiroshi , Hamana Hiroshi , Narita Tadashi
Published: September 2009

Novel fluorinated polymer synthesis with anionic polyaddition by double Michael addition reaction of 2‐trifluoromethylacrylate derivatives with ethyl cyanoacetate (ECA) was proposed. Diaddition product of ECA with phenyl 2‐trifluoromethylacrylate was yielded in high yield by the catalysis of sodium ethoxide in tetrahydrofuran at 60 °C. Sodium hydroxide catalyzed double Michael addition reaction also produced diaddition product in high yield. Novel anionic polyaddition of 1,4‐phenylene bis(2‐trifluoromethylacrylate) [CH2C(CF3)COOC6H4OCOC(CF3)CH2] (PBFA) with ECA afforded the polymer of 1.2 × 104 as the highest molecular weight. The isolated polymer gave the polymer of 2.8 × 104 as a molecular weight by the reaction of the isolated polymer with PBFA in the presence of sodium ethoxide; which proved that the polymer end groups were mainly ECA moieties. The reaction mechanism that the proton abstraction from ECA followed by the addition of 2trifluoromethylacrylate was proposed. The reaction of acetylacetone with PBFA was also examined to give the polymer of 7.6 × 103 as the highest molecular weight catalyzed by sodium hydroxide at room temperature. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5698–5708, 2009
A non‐PFT (polymerization filling technique) approach to poly(ethylene‐co‐norbornene)/MWNTs nanocomposites by in situ copolymerization with scandium half‐sandwich catalyst
Authors: Ravasio Andrea , Boggioni Laura , Tritto Incoronata , D'arrigo Cristina , Perico Angelo , Hitzbleck Julia , Okuda Jun
Published: September 2009

The in situ synthesis of ethylene‐co‐norbornene copolymers/multi‐walled carbon nanotubes (MWNTs) nanocomposites was achieved by rare‐earth half‐sandwich scandium precursor [Sc(η5‐C5Me4SiMe3)(η1‐CH2SiMe3)2(THF)] (1) activated by [Ph3C][B(C6F5)4], through a non‐PFT (Polymerization Filling Technique) approach. MWNTs nanocomposites with low aluminum residue were obtained with excellent yields even though small amounts of triisobutylaluminium were needed as scavenger to prevent catalyst poisoning by MWNT impurities. MWNT bundles were disaggregated and highly coated with Poly(ethylene‐co‐norbornene) [P(E‐co‐N)] as revealed by transmission electron microscopy. Interestingly, P(E‐co‐N) copolymers showed Tg over 130 °C as well as norbornene content over 50 mol %; both values were higher than those obtained by the cationic active species in 1/[Ph3C][B(C6F5)4]. A series of copolymerization reactions by 1/[Ph3C][B(C6F5)4]/AliBu3 without MWNTs produced copolymers with the same unexpected features. The NMR analysis revealed the presence of rac‐ENNE and rac‐ENNNE sequences. Thus, AliBu3 changed the stereoirregular alternating copolymer microstructure produced by 1/[Ph3C][B(C6F5)4]. We conclude that AliBu3 is not only a scavenger for CNT impurities, but it reacts with the THF ligand to give coordinatively unsaturated active species. Finally, P(E‐co‐N)/MWNT masterbatches were mixed with commercial TOPAS to produce cyclic olefin copolymer nanocomposites with excellent dispersion of filler. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5709–5719, 2009
Influences of steric bulkiness in hydrotris(pyrazolyl)borate ligands on ethylene polymerization reaction
Authors: Nabika Masaaki , Kiuchi Seiki , Miyatake Tatsuya , Fujisawa Kiyoshi
Published: September 2009

Manganese(II) complex catalysts with hydrotris(pyrazolyl)borate ligands have been examined on their catalytic performance in ethylene polymerization and ethylene/1‐hexene copolymerization. The activities of [Mn(L6)(Cl)(NCMe)] (1) and [Mn(L10)(Cl)] (2) activated by Al(i‐Bu)3/[Ph3C][B(C6F5)4] for ethylene polymerization go up to 326 and 11 kg mol (cat−1) h−1, respectively, (L6− = hydrotris(3‐phenyl‐5‐methyl‐1‐pyrazolyl)borate anion, L10− = hydrotris(3‐adamantyl‐5‐isopropyl‐1‐pyrazolyl)borate anion). In particular, for ethylene/1‐hexene copolymerization, complex 1 gives high‐molecular‐weight poly(ethylene‐co‐1‐hexene)s with the highest Mw of 439,000 in manganese olefin polymerization catalyst systems. Moreover, the 1‐hexene incorporation by complex 1 seems more efficient than that by [Mn(L3)(Cl)] (4) (L3− = hydrotris(3‐tertiary butyl‐5‐isopropyl‐1‐pyrazolyl)borate anion). In this work, we demonstrated that the coordination geometry and coordination number are also important factors for ethylene polymerization reaction as well as steric hindrances and ligand frameworks in our manganese(II) catalysts. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5720–5727, 2009
Synthesis of polyester having pendent hydroxyl groups via regioselective dehydration polycondensations of dicarboxylic acids and diols by low temperature polycondensation
Authors: Shibata Yosuke , Takasu Akinori
Published: September 2009

In this article, we describe the one‐step synthesis of polyesters having pendent hydroxyl groups by Lewis acid‐catalyzed, regioselective, dehydration polycondensations of diols (glycerol and sorbitol) and dicarboxylic acids [tartaric acid (TA) and malic acid (MA)] containing pendent hydroxyl groups, using low temperature polycondensation technique. Direct polycondensations of TA or MA and 1,9‐nonanediol catalyzed by scandium trifluoromethanesulfonate [Sc(OTf)3] successfully yielded linear polyesters having hydroxyl functionality (Mn = ca. 1.0 × 104). To demonstrate the reactivity of the pendent hydroxyl group, a glycosidation was performed. Poly(nonamethylene L‐malate) showed significant higher biodegradability, compared with poly(nonamethylene L‐tartrate) or poly(nonamethylene succinate). Stable poly(nonamethylene L‐tartrate) emulsion could be prepared using poly(vinyl alcohol) as the surfactant, although emulsions consisting of poly(nonamethylene succinate) were unstable and phase‐separated within a few days. Furthermore, direct polycondensations of TA and diethylene glycol (DEG) or triethylene glycol (TEG) successfully produced water‐soluble polyesters having hydroxyl groups. This new polycondensation system may be extremely effective not only for advanced material design using functional monomers but also for effective utilization of biomass resources as chemical substances. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5747–5759, 2009
Fatty acid derived phosphorus‐containing polyesters via acyclic diene metathesis polymerization
Authors: De Espinosa Lucas Montero , Ronda Juan C. , Galià Marina , Cádiz Virginia , Meier Michael A.R.
Published: September 2009

The acyclic diene metathesis (ADMET) polymerization of a phosphorus‐containing α,ω‐diene prepared from a plant oil derived building block is reported. Different ruthenium based metathesis catalysts and conditions were tested to optimize the ADMET polymerization of this monomer. Undecylenyl undecenoate was used as fully renewable comonomer to obtain polyesters with different phosphorus contents and to increase the renewable content of the final polymers. Copolymerization caused marked variations in the molecular weights leading to polyesters from 6 to 38 KDa. The effect of the ADMET polymerization temperature in the thermal properties of the copolymers was studied and their thermal degradation and flame retardant properties were evaluated. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5760–5771, 2009
Enzymatic ring‐opening polymerization of ε‐caprolactone by Yarrowia lipolytica lipase in ionic liquids
Authors: Barrera‐Rivera Karla A. , Marcos‐Fernández Ángel , Vera‐Graziano Ricardo , Martínez‐Richa Antonio
Published: September 2009

Yarrowia lipolytica (YLL), Candida rugosa (CRL), and porcine pancreatic lipase (PPL) were employed successfully as catalysts in the enzymatic ring‐opening polymerization (ROP) of ε‐caprolactone in the presence of 1‐ethyl‐3‐methylimidazolium tetrafluoroborate ([EMIM][BF4]), 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([BMIM][BF4]), 1‐butylpyridinium tetrafluoroborate ([BuPy][BF4]), 1‐butylpyridinium trifluoroacetate ([BuPy][CF3COO]), 1‐ethyl‐3‐methylimidazolium nitrate ([EMIM][NO3]) ionic liquids. Poly(ε‐caprolactone)s (PCLs) with molecular weights (Mn) in the range of 300–9000 Da were obtained. 1H‐ and 13C‐NMR analyses on PCLs formed by YLL, CRL, and PPL showed asymmetric telechelic α‐hydroxy‐ω‐carboxylic acid end groups. Differences between CP‐MAS and MAS spectra are observed and discussed in terms of morphology. MALDI‐TOF spectra show the formation of at least seven species. Differential scanning calorimetry (DSC) and Wide Angle X‐Ray Scattering (WAXS) results demonstrate the high degree of crystallinity present in all the polyesters. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5792–5805, 2009
Porous polyurethanes synthesized within high internal phase emulsions
Authors: David Dganit , Silverstein Michael S.
Published: September 2009

PolyHIPE are highly porous, emulsion‐templated polymers typically synthesized via free‐radical polymerization within a water‐in‐oil (W/O) high internal phase emulsion (HIPE) whose dispersed, aqueous phase occupies more than 74% of the volume. The synthesis of a polyHIPE containing biodegradable polymers is not straightforward because the presence of both an organic phase and an aqueous phase within the HIPE limits the type of polymerization reactions that can be used. This article describes the synthesis of polyHIPE containing biodegradable poly(ε‐caprolactone) (PCL) groups through the step‐growth reaction of a diisocyanate with a flexible PCL triol to form a crosslinked polyurethane. The reaction of the diisocyanate with the water in the HIPE produced urea groups and large bubbles from the generation of CO2. The polymer walls between these bubbles consisted of a porous, emulsion‐templated structure. Polymerization with an excess of diisocyanate produced a significant enhancement in the amounts of urea and CO2. The reduction in the flexible PCL content and the enhancement in the rigid urea content produced an increase in wall modulus that was over 20‐fold. The ability to synthesize polyHIPE through such step‐growth reactions is an important advance in the adaptation of polyHIPE for such applications as tissue engineering. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5806–5814, 2009
Sulfonated poly(ether sulfone)s with binaphthyl units as proton exchange membranes for fuel cell application
Authors: Matsumoto Kazuya , Nakagawa Taijiro , Higashihara Tomoya , Ueda Mitsuru
Published: September 2009

Sulfonated poly(ether sulfone)s containing binaphthyl units (BNSHs) were successfully prepared for fuel cell application. BNSHs, which have very simple structures, were easily synthesized by postsulfonation of poly(1,1′‐dinaphthyl ether phenyl sulfone)s and gave tough, flexible, and transparent membranes by solvent casting. The BNSH membranes showed low water uptake compared to a typical sulfonated poly(ether ether sulfone) (BPSH‐40) membrane with a similar ion exchange capacity (IEC) value and water insolubility, even with a high IEC values of 3.19 mequiv/g because of their rigid and bulky structures. The BNSH‐100 membrane (IEC = 3.19 mequiv/g) exhibited excellent proton conductivity, which was comparable to or even higher than that of Nafion 117, over a range of 30–95% relative humidity (RH). The excellent proton conductivity, especially under low RH conditions, suggests that the BNSH‐100 membrane has excellent proton paths because of its high IEC value, and water insolubility due to the high hydrophobicity of the binaphthyl structure. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5827–5834, 2009
Association phenomena of the ferrocenylsiloxane polyamide in solution
Authors: Cazacu Maria , Racles Carmen , Airinei Anton , Alexandru Mihaela , Vlad Angelica
Published: September 2009

A ferrocenyl‐siloxane polyamide, poly{1,1′‐ferrocene‐diamide‐[1,3‐bis(propylene)tetramethyldisiloxane]}, FAS, prepared by polycondensation in solution (methylene chloride) of 1,1′‐di(chlorocarbonyl)ferrocene with 1,3‐bis(aminopropyl)tetramethyldisiloxane has been dissolved in various concentrations in the range 0–1.5 g/dL in dimethylformamide. The solutions were investigated by tensiometry, viscometry, and UV–vis spectrophotometry at different temperatures. The results suggested the association occurrence, depending on the two parameters (concentration and temperature). The aggregates formation and their sizes were emphasized by dynamic light scattering and scanning electron microscopy. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5845–5852, 2009
Preparation of three‐dimensional poly(dimethylsiloxane) (PDMS) with movable cross‐linking
Authors: Miki Kazuya , Inamoto Yasunari , Inoue Shuka , Uno Takahiro , Itoh Takahito , Kubo Masataka
Published: September 2009

A pentamethylcyclotrisiloxane moiety was introduced into cyclic polystyrene (cPSt) and cyclic PDMS (cPDMS) to obtain noncovalent cross‐linking agents, D3‐cPSt and D3‐cPDMS, respectively. Anionic ring‐opening polymerization of octamethylcyclotetrasiloxane (D4) in nitrobenzene was carried out in the presence of D3‐cPSt to obtain a cloudy white PDMS gel as a precipitation. On the other hand, bulk copolymerization of D3‐cPDMS with D4 proceeded in a homogeneous state to give a colorless transparent PDMS gel in high yield. The formation of mechanically linked PDMS with movable cross‐linking was indicated by control experiment. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5882–5890, 2009
Controlled preparation of poly(ethylene glycol) and poly(L‐lactide) block copolymers in the presence of a monomer activator
Authors: Hyo Lee Sang , Oh Jae Min , Son Jin Soo , Lee Jung Won , Kim Byung Soo , Khang Gilson , Han Dong Keun , Kim Jae Ho , Lee Hai Bang , Kim Moon Suk
Published: September 2009

Polymerization of L‐lactide (LA) was performed in the presence of trifluoromethanesulfonic acid (CF3SO3H) via an activated monomer mechanism to synthesize various block copolymers composed of polyethyleneglycol (PEG) and poly(L‐lactide) (PLLA). The PLLAs obtained had molecular weights close to theoretical values calculated from LA/PEG molar ratios and exhibited monomodal GPC curves. A 1H NMR spectroscopic study showed that the LA carbonyl carbon signal exhibited a change in chemical shift to lower field, caused by electron delocalization of the carbonyl carbon by CF3SO3H. We successfully prepared PEG and PLLA block copolymers using this activated monomer mechanism. We concluded that synthesis proceeded by LA ring‐opening polymerization caused by PEG in the presence of CF3SO3H to yield PEG and PLLA block copolymers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5917–5922, 2009
Evaluation of a Range of Surface Modifications for the Enhancement of Lateral Flow Assays on Cyclic Polyolefin Micropillar Devices
Authors: Dudek Magdalena M. , Gandhiraman R. P. , Volcke C. , Daniels Stephen , Killard Anthony J.
Published: September 2009

We report the evaluation of a range of surface modifications for the formation of a stable, uniform, hydrophilic surface on cyclic polyolefin‐based microfluidic devices. The surface modifications employed were oxygen plasma treatment alone, or in combination with polyelectrolyte (PE) modifications or chemical vapour deposition (CVD) of silicon dioxide as well as dextran modification. The surface modifications were characterised by atomic force microscopy (AFM), contact angle (CA) measurements and both quantitative and qualitative lateral flow measurements. It was demonstrated that the silicon dioxide and PE treatments produced the lowest CAs and therefore most hydrophilic surfaces, which was reflected in the improved lateral flow rates on this normally hydrophobic polymer. However, the non‐uniformity of the PE coating as well as its reduced reproducibility and stability over time in comparison to the silicon dioxide coating meant that the silicon dioxide was the favoured surface modification.

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