bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermosensitive diblock copolymers with designed molecular weight distribution: Synthesis by continuous living cationic polymerization and micellization behavior
Authors: Seno Ken‐Ichi , Kanaoka Shokyoku , Aoshima Sadahito 
Published: February 2008

AbstractThe synthesis of diblock copolymers with designed molecular weight distributions (MWDs) was successfully demonstrated in a continuous living cationic polymerization system using simple equipment. The control of MWDs was achieved by gradually feeding a polymerization reaction mixture into a terminating agent. As thermosensitive diblock copolymers, poly(vinyl ethers) containing a thermosensitive segment with oxyethylene side chains and a hydrophilic segment were prepared. The polymerization was carried out in a gas‐tight microsyringe, and the polymerization mixture was added continuously into methanol during the second‐stage polymerization. The self‐association behavior of the resulting diblock copolymers was evaluated by dynamic light scattering in water. MWD‐designed polymers with thermosensitive segments that varied continuously in length and hydrophilic segments of nearly uniform lengths formed micelles with a broad size distribution. Conversely, polymers with nearly uniform thermosensitive segments and hydrophilic segments of different lengths formed micelles with a narrow size distribution, as observed with conventional narrow MWD diblock copolymers. Thus, the MWD of the thermosensitive segment proved a decisive factor in achieving fine control of self‐association. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2212–2221, 2008
Pd(0)‐catalyzed polycondensation of methyl propargyl carbonate and bisphenols under stoichiometrically imbalanced conditions
Authors: Takemura Tomonori , Sugie Koji , Nishino Hiroshi , Kawabata Satoshi , Koizumi Toshio 
Published: February 2008

AbstractWe found that a novel Pd(0)‐catalyzed polycondensation of methyl propargyl carbonate (1) and bisphenol analogs 4 such as 4,4′‐dihydroxydiphenyl ether (4b) proceeded successfully and gave polyethers 5 having exomethylene groups. The polycondensation was affected by the kind of bisphenol analogs used. The molar ratio of 1 and 4 also affected the polymerization behavior. Polyethers 5 with higher molecular weights were obtained by polymerization with 0.5 equiv of 4 toward 1. The use of 1 equiv of 4 gave poor results. When 4,4′‐dihydroxybenzophenone (4d) was employed as a nucleophile, benzenesulfonamide (13) was needed as an additive for obtaining the corresponding polyether with higher molecular weight. The Pd(0)‐catalyzed condensation of 1 and p‐hydroxyacetophenone was conducted as a model reaction. The desired compound and three by‐products were produced. Two of the by‐products were formed by reaction of 1 and methanol liberated from 1. The other one appeared to be formed via hydrogenolysis. The formation of the by‐products suggested that some terminal reactions took place in the polycondensation of 1 and 4. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2250–2261, 2008
Power‐law scaling of structured poly(p‐xylylene) films deposited by oblique angle
Authors: Cetinkaya Murat , Malvadkar Niranjan , Demirel Melik C. 
Published: February 2008

AbstractThis study describes the evolution and growth of structured polymers by oblique angle deposition of poly(p‐xylylene) (PPX) derivatives. The deposition of structured PPX polymers have been demonstrated recently, but the mechanism of growth has not been studied. Here, we provide experimental evidence for the growth of structured PPX polymers by an atomic force microscope, electron microscope, and a profilometer. Individual columns expand with respect to their heights according to a power‐law, d = chp, where d is the column diameter, c and p are constants, and h is the height of a column. Values of p for structured poly(chloro‐p‐xylylene), poly(trifloroacetly‐p‐xylylene‐co‐p‐xylylene), and poly(bromo‐p‐xylylene) films are estimated as 0.11 ± 0.01, 0.15 ± 0.01, and 0.18 ± 0.01, respectively. This result is different from the traditional oblique angle deposition processes of nonpolymeric materials where the surface diffusion is low. Further analysis with two‐dimensional power spectral density (PSD) method showed that the ordering of columns is quasi‐periodic. Additionally, the X‐ray and transmission electron microscope characterization of the columns revealed that the columns are semicrystalline. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 640–648, 2008
Low‐temperature growth of high quality AlN films on carbon face 6H‐SiC
Authors: Kim Myunghee , Ohta Jitsuo , Kobayashi Atsushi , Fujioka Hiroshi , Oshima Masaharu 
Published: February 2008

AbstractIn the reciprocal space map of Fig. 4 in Kim et al. [phys. stat. sol. (RRL) 2, No. 1, 13–15 (2008)] the labelling of the horizontal axis was incorrect. The corrected figure is presented here. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spatial and temporal aspects of agricultural sustainability in the semi‐arid tropics: a case study in Mbeere district, Eastern Kenya
Authors: Onduru Davies D , Du Preez Chris C 
Published: February 2008

AbstractA study was conducted in the semi‐arid Mbeere district, Eastern Kenya, to determine spatial and temporal variability of crop yields and climatic factors and their impacts on sustainability of semi‐arid agriculture. Spatial aspects were assessed by conducting a survey of on‐farm crop yields and using a computer model (QUEFTS) to predict maize yields from soil chemical indices. Temporal aspects were studied using time‐series data (rainfall, temperature and crop yields). The study did not find a significant correlation between farmers' actual yields and QUEFTS predictions, and soil nutrients were thus not the only factors influencing maize yields in the study area. Other yield‐reducing factors (climate and management) not accounted for in the QUEFTS model played a role. Grain yields of staple food crops were highly variable, fluctuating in time and space, and suboptimal. Particular aspects of rainfall (e.g. the short rains, for cowpeas and beans) were more important than mean annual rainfall in determining crop yields, and factors other than rainfall and soil fertility apparently played a role. The observed low grain yields, large yield gaps and high rainfall variability challenge the sustainability of these farming systems. Copyright © 2008 John Wiley & Sons, Ltd
Imaging of Primary and Metastatic Pancreatic Cancer Using a Fluorophore‐Conjugated Anti‐CA19‐9 Antibody for Surgical Navigation
Authors: McElroy Michele , Kaushal Sharmeela , Luiken George A. , Talamini Mark A. , Moossa A. R. , Hoffman Robert M. , Bouvet Michael 
Published: February 2008

AbstractBackgroundDespite recent surgical advances, pancreatic cancer remains the fourth leading cause of cancer‐related death in the United States. This is due to inaccurate staging and difficulty in achieving negative margins at the time of pancreaticoduodenectomy. CA19‐9 is a carbohydrate tumor‐associated antigen found in up to 94% of pancreatic adenocarcinomas. In this study we investigate the use of a fluorophore‐labeled anti‐CA19‐9 monoclonal antibody to improve intraoperative visualization of both primary and metastatic tumors in a mouse model of pancreatic cancer.MethodsA monoclonal antibody specific for CA19‐9 was conjugated to a green fluorophore and delivered to tumor‐bearing mice as a single intravenous (IV) dose. Intravital fluorescence imaging was used to localize tumor implants 24 h after antibody administration.ResultsUsing fluorescence imaging, the primary tumor was clearly visible at laparotomy, as were small metastatic implants within the liver and spleen and on the peritoneum. These tumor implants, which were nearly impossible to see using standard bright‐field imaging, demonstrated clear fluorescence under LED light excitation. The fluorescence signal within the tumor tissue was maintained for over 3 weeks after a single administration of the labeled antibody. Histologic evaluation of tissue from animals treated with the conjugated anti‐CA19‐9 antibody likewise revealed strong staining of the tumor cells with minimal background staining of the peritumoral stroma.ConclusionsFluorophore‐labeled anti‐CA19‐9 offers a novel intraoperative imaging technique for enhanced visualization of primary and metastatic tumors in pancreatic cancer when CA19‐9 expression is present and may improve intraoperative staging and efficacy of resection.
Papillary Microcarcinoma
Authors: Noguchi Shiro , Yamashita Hiroto , Uchino Shinya , Watanabe Shin 
Published: February 2008

AbstractBackgroundPapillary microcarcinoma (PMC) is increasing in incidence because of diagnosis by ultrasound‐guided fine‐needle aspiration cytology.MethodsBetween January 1966 and December 1995, we treated 6019 patients with papillary cancer; among them, 2070 patients with PMC were studied.ResultsPMC is essentially very similar to papillary cancer that is 11 mm or larger and has a very good prognosis. Smaller tumors and younger patients have a better prognosis. Among PMC, larger tumors (6–10 mm) recur in 14% at 35 years compared with 3.3% in patients with smaller tumors. Patients older than 55 years have recurrence in 40% at 30 years, with a worse prognosis than younger patients who have a recurrence rate of less than 10%. Extracapsular invasion by the primary tumor also has a higher recurrence rate. The majority of recurrences are in the neck. Therefore, annual ultrasound of the neck is effective for recurrence surveillance.ConclusionPapillary microcarcinoma is similar to larger papillary carcinomas with tumor characteristics and age‐based recurrence rate that extends for many years, justifying long surveillance after surgery.
Endoscopic Evaluation of Reflux Esophagitis After Proximal Gastrectomy: Comparison Between Esophagogastric Anastomosis and Jejunal Interposition
Authors: Tokunaga Masanori , Ohyama Shigekazu , Hiki Naoki , Hoshino Etsuo , Nunobe Souya , Fukunaga Tetsu , Seto Yasuyuki , Yamaguchi Toshiharu 
Published: February 2008

AbstractBackgroundAlthough proximal gastrectomy has been performed more as a function‐preserving surgery, reflux esophagitis can occur postoperatively, resulting in poor postoperative quality of life. To date, only a few reports have compared the methods of reconstruction performed after proximal gastrectomy, and the method most likely to prevent postoperative reflux esophagitis remains undetermined.MethodsA retrospective review of 76 patients who underwent proximal gastrectomy with jejunal interposition (JI) or esophagogastrostomy (EG) at the Cancer Institute Hospital between April 1996 and August 2005 was performed. Preoperative characteristics, operative findings, and postoperative gastrointestinal fiberoscopy findings were reviewed and compared between JI and EG patients. Furthermore, we investigated the relationship between the length of interposed segment and operative and postoperative findings.ResultsThe frequency of grade C or D reflux esophagitis was lower in the JI group than in the EG group (p = 0.001), although the former required a longer operation time (256.5 ± 10.2 min) than the latter (195.8 ± 8.2 min; p < 0.001). Other characteristics and postoperative clinical course did not differ between the groups. In the JI group, interposed segments 10 cm or shorter were advantageous in evaluating the remnant stomach when compared with interposed segments longer than 10 cm. No relationship was observed between the length of the interposed segment and clinical findings, except operation time.ConclusionJejunal interposition helps prevent reflux esophagitis after proximal gastrectomy. The optimal length of the interposed segment is undetermined; however, a length of 10 cm or shorter is preferred for endoscopic evaluation of the remnant stomach.
Is a T‐tube Necessary after Common Bile Duct Exploration?
Authors: Ahmed Irfan , Pradhan Charita , Beckingham Ian J. , Brooks Adam J. , Rowlands Brian J. , Lobo Dileep N. 
Published: February 2008

AbstractBackgroundT‐tube drainage used to be standard practice after surgical choledocholithotomy, but there is now a tendency in some centers to close the common bile duct (CBD) primarily. This study was designed to review the complications associated with T‐tube drainage after CBD exploration and to determine whether primary closure of the bile duct reduces postoperative morbidity.MethodsA retrospective audit was performed on patients undergoing CBD exploration between July 1997 and March 2007, who were identified from the theatre database of one teaching hospital. Intraoperative findings and postoperative complications were recorded from the clinical notes.ResultsDuring the study period, 158 patients (97 women; median age 65 (range, 25–90) years) underwent CBD exploration. A T‐tube was inserted in 91 patients (group I) and the CBD was closed primarily in 67 (group II). One or more biliary complications occurred in 26 patients (16.5%): 20 (22.0%) in group I and 6 (8.9%) in group II (p = 0.03). In group I, 15 had a biliary leak (3 needed reoperation), 2 had accidental slippage of the tube, 2 an entrapped T‐tube, and 1 a retained stone. In group II, six patients had biliary leakage, two of whom were re‐explored. Six patients in group I also had peritubal infection, necessitating the use of antibiotics. There were three deaths: two in group I (1 T–tube‐related) and 1 in group II (p = 1, not significant).ConclusionThere is a lower biliary complication rate associated with primary closure of the CBD than after T‐tube drainage.
Effects of acorn abundance on density dependence in a Japanese wood mouse (Apodemus speciosus) population
Authors: Saitoh Takashi , Vik Jon Olav , Stenseth Nils Chr. , Takanishi Toshikazu , Hayakashi Shintaro , Ishida Nobuo , Ohmori Masaaki , Morita Toshio , Uemura Shigeru , Kadomatsu Masahiko , Osawa Jun , Maekawa Koji 
Published: February 2008

AbstractWe analysed the effects of Quercus crispula acorn abundance on the density dependence of the large Japanese wood mouse Apodemus speciosus using time series data (1992–2007). The data were obtained in a forest in northern Hokkaido, Japan, by live‐trapping rodents and directly counting acorns on the ground. Acorn abundance in one year clearly influenced the abundance of wood mice in the following year in all models examined based on the Gompertz and Ricker model; in addition, the abundance of wood mice had effects on the population. Acorn abundance influenced the strength of density dependence (intraspecific competition) of the wood mouse population. When the abundance of acorns was high, density dependence was relaxed, and as a result the equilibrium density at which the population growth rate decreased to zero became higher. Those effects of acorn abundance were regarded as a nonlinear perturbation effect (sensu Royama 1992). The nonlinearity of density dependence was also detected; higher densities had stronger effects on population growth rates.
Neurogenic hip dislocation in cerebral palsy: Quality of life and results after hip reconstruction
Authors: Krebs Alexander , Strobl Walter M. , Grill Franz 
Published: February 2008

Background At birth, no difference exists between the hips of children with spastic cerebral palsy and the hips of other children. The typical pathologic deformities of the hips in children with spastic cerebral palsy develop as the child gets older. One of our goals was to evaluate the change in quality of life of children with cerebral palsy after hip reconstruction. For classification of the children's condition, we assessed sitting and standing abilities and used the Gross Motor Function Classification System. To evaluate the effect of hip dislocation on the spine, we assessed symmetry while the patient was lying down, sitting, and standing. Methods The results of surgical reconstruction of hip joints in 54 patients with severe cerebral palsy who had 66 severely subluxated or dislocated hip joints were retrospectively analyzed. The study was based on a research questionnaire with a mean follow-up of 4 years 10 months. The purpose of the questionnaire was to evaluate the pain, functional abilities, symmetry, and independence of the patients by using the modified Barthel index. Results Pain was fully relieved in 62 and was eased in 35% of preoperatively painful hips. The functional abilities of sitting and standing were not influenced statistically significantly by the operation. An improvement in sitting symmetry was observed in 40% and improvement in lying symmetry was observed in 32% of the patients. The mean center-edge angle improved from −24.9° ± 39° (mean ± standard deviation) to 25.9° ± 14°. The acetabular index improved from 30.2° ± 8° to 17.1° ± 7°. Conclusions The independence of the patients, based on the modified Barthel index, did not change significantly after surgery. Most improvements in quality of life were observed in those patients who had pain in the hip before the operation as a result of reduction of pain and improved mobility of the hip.
Impact of different bone marrow cell preparations on left ventricular remodelling after experimental myocardial infarction
Authors: Frantz Stefan , Vallabhapurapu Duttu , Tillmanns Jochen , Brousos Nikos , Wagner Helga , Henig Kristina , Ertl Georg , Müller Albrecht M. , Bauersachs Johann 
Published: February 2008

AbstractObjective:Bone marrow (BM)‐derived haematopoietic stem cells have been proposed as a potential cell source to functionally engraft the myocardium and to improve cardiac function after myocardial infarction (MI). However, experimental and clinical data are inconsistent. Since the specific characteristics of different BM cell subsets could influence their therapeutic potential we determined the effect of different BM cell populations on left ventricular remodelling after MI.Methods and results:MI was induced in female mice by coronary artery ligation. Surviving mice were randomised to receive either: total BM, mature Lin+ or primitive Lin− cells from male mice, or saline, via intracardiac injection. Injected cells were detected in the infarct and border zone by PCR for Y‐chromosomal sequences. Serial transthoracic echocardiography was performed 1, 21, and 42 days after MI. Over a period of 6 weeks, mortality was not different between the groups. After MI, animals exhibited left ventricular dilatation, as expected. Left ventricular remodelling was not influenced by Lin+ or Lin− BM cells but was partially improved by unfractionated BM cell injection. Paracrine secretion of cytokines (e.g. IL‐6, GM‐CSF) was differentially regulated in supernatants of cultured BM cells.Summary:Treatment with unfractionated BM cells, but not Lin+, or Lin− cells partially improved cardiac remodelling and function after MI. This may be mediated by paracrine effects.
Dimensional representations of DSM-IV cluster B personality disorders in a population-based sample of Norwegian twins: a multivariate study
Authors: Torgersen S. , Czajkowski N. , Jacobson K. , Reichborn-Kjennerud T. , Røysamb E. , Neale M. C. , Kendler K. S. 
Published: February 2008

BackgroundThe personality disorders (PDs) in the ‘dramatic’ cluster B [antisocial (ASPD), histrionic (HPD), narcissistic (NPD) and borderline (BPD)] demonstrate co-morbidity. However, the degree to which genetic and/or environmental factors influence their co-occurrence is not known and, with the exception of ASPD, the relative impact of genetic and environmental risk factors on liability to the cluster B PDs has not been conclusively established.MethodPD traits were assessed in 1386 Norwegian twin pairs between the age of 19 and 35 years using the Structured Interview for DSM-IV Personality Disorders (SIDP-IV). Using the statistical package Mx, multivariate twin models were fitted to dimensional representations of the PDs.ResultsThe best-fitting model, which did not include sex or shared family environment effects, included common genetic and environmental factors influencing all four dramatic PD traits, and factors influencing only ASPD and BPD. Heritability was estimated at 38% for ASPD traits, 31% for HPD traits, 24% for NPD traits and 35% for BPD traits. BPD traits had the lowest and ASPD traits the highest disorder-specific genetic variance.ConclusionThe frequently observed co-morbidity between cluster B PDs results from both common genetic and environmental influences. Etiologically, cluster B has a ‘substructure’ in which ASPD and BPD are more closely related to each other than to the other cluster B disorders.
Strong Gravitational Lensing: Bright Galaxies & Lost Dark-Matter
Authors: Koopmans L. V. E. 
Published: February 2008

AbstractGravitational lensing and stellar dynamics provide two complementary methods to probe the smooth and clumpy stellar and dark-matter mass distribution in early-type galaxies, currently already over a range of two orders of magnitude in virial mass, more than ten orders of magnidude in dynamic mass range in each galaxy (i.e. from stars, CDM substructure to massive dark-matter halos), over 0–1 in redshift, and a range of 0–100 effective radii. This makes their unification a powerful new tool in the study of the formation, structure and evolution of these massive systems. I review recent results that we obtained, based on gravitational lens systems from the Sloan Lens ACS Survey (SLACS), and outline some ongoing and future work.
Scaling Relations of Dwarf Galaxies without Supernova-Driven Winds
Authors: Tassis K. , Kravtsov A. V. , Gnedin N. Y. 
Published: February 2008

AbstractNearby dwarf galaxies exhibit tight correlations between their global stellar and dynamical properties, such as circular velocity, mass-to-light ratio, stellar mass, surface brightness, and metallicity. Such correlations have often been attributed to gas or metal-rich outflows driven by supernova energy feedback to the interstellar medium. We use high-resolution cosmological simulations of high-redshift galaxies with and without energy feedback, as well as analytic modeling, to investigate whether the observed correlations can arise without supernova-driven outflows. We find that the simulated dwarf galaxies exhibit correlations similar to those observed as early as z ≈ 10 and the addition of realistic levels of supernova energy feedback has no appreciable effect on these correlations. We also show that the correlations can be well reproduced by our analytic model that accounts for gas inflow but without outflows, and star formation rate obeying the Kennicutt-Schmidt law with a critical density threshold. We argue that correlations in simulated galaxies arise due to the increasingly inefficient conversion of gas into stars in low-mass dwarf galaxies rather than supernova-driven outflows.
Dark-Matter Content of Early-Type Galaxies with Planetary Nebulae
Authors: Napolitano N. R. , Romanowsky A. J. , Coccato L. , Capaccioli M. , Douglas N. G. , Noordermeer E. , Merrifield M. R. , Kuijken K. , Arnaboldi M. , Gerhard O. , Freeman K. C. , De Lorenzi F. , Das P. 
Published: February 2008

AbstractWe examine the dark matter properties of nearby early-type galaxies using planetary nebulae (PNe) as mass probes. We have designed a specialised instrument, the Planetary Nebula Spectrograph (PN.S) operating at the William Herschel telescope, with the purpose of measuring PN velocities with best efficiency. The primary scientific objective of this custom-built instrument is the study of the PN kinematics in 12 ordinary round galaxies. Preliminary results showing a dearth of dark matter in ordinary galaxies (Romanowskyet al. 2003) are now confirmed by the first complete PN.S datasets. On the other hand early-type galaxies with a “regular” dark matter content are starting to be observed among the brighter PN.S target sample, thus confirming a correlation between the global dark-to-luminous mass virial ratio (fDM=MDMM*) and the galaxy luminosity and mass.