bluuebunny/crossref_metadata_2025_split huggingface dataset:
Organic solvent dispersion of poly(3,4‐ethylenedioxythiophene) with the use of polymeric ionic liquid
Authors: Kim Tae Young , Lee Tae Hee , Kim Jong Eun , Kasi Rajeswari M. , Sung Chong S. P. , Suh Kwang S. 
Published: September 2008

AbstractA nonaqueous dispersion of poly(3,4‐ethylenedioxythiophene) (PEDOT) was prepared with the use of polymeric ionic liquid (PIL) as a polymerization template and phase transfer medium. A detailed investigation was performed to understand the role of PIL in the course of polymerization and phase transfer reaction. On the basis of our findings from X‐ray photoelectric spectroscopy (XPS), we propose a mechanism by which the PIL leads to the nanostructured PEDOT colloids in various organic solvents and thus facilitating smoother surface morphologies of the PEDOT‐PIL films. In addition, the enhancement of charge transport was observed for PEDOT‐PIL complex when compared with PEDOT without PIL. Raman spectroscopy indicates that there is a reduced interaction between the charge carriers on the PEDOT and the counter ions bound to PIL, thus promoting charge carrier hopping rates. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6872–6879, 2008
Synthesis and characterization of nanomagnetite thermosets based on benzoxazines
Authors: Kiskan Baris , Demirel A. Levent , Kamer Orhan , Yagci Yusuf 
Published: September 2008

AbstractNanomagnetite thermosets were obtained by thermally activated ring opening copolymerization of benzoxazine groups coated on the surface of the nanomagnetite with bare benzoxazine. For this purpose, carboxylic acid containing 1,3‐benzoxazine was synthesized and covalently bonded on magnetite nanoparticles by postcoating method. The average size of benzoxazine coated nanoparticles was 40–100 nm as determined by Dynamic Light Scattering (DLS), Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM) measurements. The crystal structure of benzoxazine coated nanoparticles was shown to be magnetite by X‐ray diffraction (XRD) analysis. Thermally activated curing behavior of nanomagnetite‐benzoxazines has also been studied by differential scanning calorimetry (DSC). Magnetic and thermal properties of the cured samples were investigated. It was shown that the precursor nanomagnetite benzoxazine and cured samples exhibited typical ferromagnetic character with low coercivities between 1.5 and 2.5 Oe. The cured samples showed high thermal stability. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6780–6788, 2008
Environmental context, managerial cognition, and strategic action: an integrated view
Authors: Nadkarni Sucheta , Barr Pamela S. 
Published: September 2008

AbstractThis study addresses an apparent disconnect between two views of strategic action: the ‘economic view,’ which contends that industry structure is the primary influence on strategic action, and the ‘cognitive view,’ which suggests that managerial cognition drives strategic action. We argue that this disconnect has created artificial boundaries between the two perspectives and has limited our ability to develop holistic explanations of strategic action. In response, we develop an integrated model that answers two questions: 1) Does industry context affect managerial cognition? 2) Does managerial cognition mediate the relationship between industry context and strategic responses to environmental changes? To examine these questions, we study the relationship between industry velocity, the structure of top management's cognitive representation of the environment, and the speed of response to environmental events. We find that industry velocity influences the structure of cognitive representations, which in turn influence the speed of response to environmental events. These results support our contention that both industry and cognition variables are critical in developing explanations of strategic actions. These results have implications for our understanding of the development of top managers' beliefs, the relationship between beliefs and action, and the nature of the complex relationship between industry context, managerial cognition, and strategic action. Copyright © 2008 John Wiley & Sons, Ltd.
Envy, comparison costs, and the economic theory of the firm
Authors: Nickerson Jack A. , Zenger Todd R. 
Published: September 2008

AbstractAn economic theory of the firm must explain both when firms supplant markets and when markets supplant firms. While theories of when markets fail are well developed, the extant literature provides a less than adequate explanation of why and when hierarchies fail and of actions managers take to mitigate such failure. In this article, we seek to develop a more complete theory of the firm by theorizing about the causes and consequences of organizational failure. Our theory focuses on the concept of social comparison costs that arise through social comparison processes and envy. While transaction costs in the market provide an impetus to move activities inside the boundaries of the firm, we argue that envy and resulting social comparison costs motivate moving activities outside the boundary of the firm. More specifically, our theory provides an explanation for ‘managerial’ diseconomies of both scale and scope—arguments that are independent from traditional measurement, rent seeking, and competency arguments—that provides new insights into the theory of the firm. In our theory, hierarchies fail as they expand in scale because social comparison costs imposed on firms escalate and hinder the capacity of managers to optimally structure incentives and production. Further, hierarchy fails as a firm expands in scope for the simple reason that the costs of differentially structuring compensation within the firm to match the increasing diversity of activities also rises with increasing scope. In addition, we explore how social comparison costs influence the design of the firm through selection of production technologies and compensation structures within the firm. Copyright © 2008 John Wiley & Sons, Ltd.
Bigger and safer: the diffusion of competitive advantage
Authors: Greve Henrich R. 
Published: September 2008

AbstractResearch on the diffusion of technologies that give competitive advantage is needed to understand the role of technology in competition. Predictions on which firms first obtain useful technologies are made by cluster theory, which holds that the diffusion is geographically bounded, and network theory, which holds that adoption is more rapid in central network positions. These predictions can be evaluated using data on the diffusion of supplier innovations that give competitive advantage to firms in the buyer industry. Here, the diffusion of new ship types is studied using the heterogeneous diffusion model and data on shipping firm‐shipbuilder networks, showing that valuable innovations remain rare because they are not adopted by distant firms in geographical and network space. The strong influence of geographically dispersed interfirm networks on technology diffusion justifies a greater role of interorganizational networks in the theory of competitive advantage. Copyright © 2008 John Wiley & Sons, Ltd.
Why firms make unilateral investments specific to other firms: the case of OEM suppliers
Authors: Kang Min‐Ping , Mahoney Joseph T. , Tan Danchi 
Published: September 2008

AbstractThis study examines why and under what conditions firms will make unilateral relationship‐specific investments to their transaction partners. We propose that firms are more likely to make such investments when the investment yields positive economic spillover values for other transactions with the same exchange partners as well as for third‐party transactions. We also model two types of positive inter‐project spillover effects that a transaction may generate: knowledge spillovers and reputation spillovers. We find empirical support for our developed theory in the context of Taiwanese suppliers of original equipment manufacturers. Copyright © 2008 John Wiley & Sons, Ltd.
Reliability of three‐dimensional sonographic measurements in early pregnancy using virtual reality
Authors: Verwoerd‐Dikkeboom C. M. , Koning A. H. J. , Hop W. C. , Rousian M. , Van Der Spek P. J. , Exalto N. , Steegers E. A. P. 
Published: September 2008

AbstractObjectiveTo establish the reliability of three‐dimensional (3D) ultrasound measurements in early pregnancy using a virtual reality system (the Barco I‐Space).MethodsThe study included 28 pregnancies with gestational ages ranging from 6 to 14 (median, 10) weeks. 3D volumes were acquired and offline measurements were made, where possible, of the yolk sac diameter, crown–rump length, biparietal diameter, head circumference and abdominal circumference, using specialized 3D imaging software (4DView). The datasets were then transferred to the Barco I‐Space, a virtual reality system that allows the observer to perceive depth and interact with volume‐rendered (ultrasound) data. The 3D rendered volumes were measured using a virtual pointer, controlled by a wireless joystick. For intraobserver variability, 3D and virtual reality volumes were measured twice by one operator. For interobserver variability, another operator performed the same measurements once. All measurements were repeated three times and their mean values were used for comparisons.ResultsAll intraclass correlation coefficients (ICCs) comparing 4DView measurements with I‐Space measurements were > 0.97. Intra‐ and interobserver ICCs for the 4DView measurements were > 0.96 and for the I‐Space ones were > 0.98, representing good agreement.ConclusionsThe application of virtual reality is a novel method of visualizing 3D ultrasound data and perception of the depth in the I‐Space offers possibilities for measuring non‐planar structures. We have demonstrated that early pregnancy measurements in the I‐Space are reliable. New areas of embryonic and fetal biometry can now be explored using this technique, which we tentatively name ‘virtual embryoscopy’. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Prenatal prediction of survival in isolated diaphragmatic hernia using observed to expected total fetal lung volume determined by magnetic resonance imaging based on either gestational age or fetal body volume
Authors: Cannie M. , Jani J. , Meersschaert J. , Allegaert K. , Done' E. , Marchal G. , Deprest J. , Dymarkowski S. 
Published: September 2008

AbstractObjectivesTo compare the predictive value of the prenatal observed to expected (o/e) lung volume as measured by fetal magnetic resonance imaging (MRI), based on an algorithm using either the gestational age or fetal body volume (FBV), for neonatal survival of fetuses with isolated congenital diaphragmatic hernia (CDH).MethodsWe included 53 fetuses with a prenatal diagnosis of isolated CDH, 26 without and 27 with prenatal tracheal occlusion, who were assessed by fetal MRI, liveborn after 32 weeks, and in whom follow‐up until discharge from the neonatal care unit was available. Measurements of lung volumes were expressed as a percentage of the appropriate mean (o/e total fetal lung volume (TFLV) × 100) either for gestational age or for FBV. Measurements of FBV were expressed as a percentage of the appropriate mean (o/e FBV × 100) for gestation. Fetuses with prenatal intervention were all assessed ≥ 24 h after balloon removal. Regression analysis was used to examine the effect on postnatal survival of either o/e TFLV based on gestational age or based on FBV, gestation at delivery, side of CDH, intrathoracic position of the liver and prenatal intervention. Receiver–operating characteristics (ROC) curves were constructed for the prediction of survival by o/e TFLV based on gestational age and o/e TFLV based on FBV, for all fetuses, as well as for those with o/e FBV between 90 and 110% and those with values beyond that range. A power calculation for the number of fetuses needed to show a difference between the ROC curves was performed.ResultsRegression analysis demonstrated that o/e TFLV based on gestational age and on FBV were the only independent predictors of postnatal survival. The area under the ROC curve for prediction of postnatal survival from the o/e TFLV based on gestational age was 0.811, and for that based on FBV it was 0.868 (P < 0.001 for both). For fetuses with o/e FBV between 90 and 110%, and those with values < 90% and > 110%, the area for measurements based on gestational age was 0.895 and 0.733, respectively; when based on FBV it was 0.906 and 0.833 (P < 0.01 for all). A minimum of 273 patients would be needed to provide a probability of 90% of detecting a difference between the areas under both ROC curves.ConclusionsIn fetuses with isolated CDH, lung volume as measured by fetal MRI was significantly correlated with survival. Prediction tended to be better by o/e TFLV based on FBV rather than gestational age. The difference in the prediction of survival between o/e TFLV based on FBV or gestational age was dependent on fetal biometry. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Mitigation of colluding route falsification attacks by insider nodes in mobilead hocnetworks
Authors: Su Xu , Boppana Rajendra V. 
Published: September 2008

AbstractColluding malicious insider nodes with no special hardware capability can use packet encapsulation and tunneling to create bogus shortcuts (in‐band wormholes) in routing paths and influence data traffic to flow through them. This is a particularly hard attack using which even a handful of malicious nodes can conduct data traffic analysis of packets or disrupt connections by dropping packets when needed. Simulation analysis shows that a disproportionately large amount of traffic goes through routes with wormholes even when a secure routing protocol (SRP) such as Ariadne is used. To mitigate such attacks and augment existing on demand SRPs, distributed packet filtering techniques based on statistical profiling of control packet propagation speeds are proposed. These techniques do not require network‐wide synchronized clocks or new packet transmissions and need only simple computations by the sources or the destinations of the connections. The proposed packet filters together with Ariadne are implemented in the Glomosim simulator and their effectiveness is evaluated. The simulation results indicate that the proposed packet filters can reduce the in‐band wormhole creation and their usage by a factor of 2‐‐10. Also, the false alarm rates of the proposed techniques are very low and have little impact on normal network throughput, making them practical for mobilead hocnetworks. Copyright © 2008 John Wiley & Sons, Ltd.
Perineural Invasion Is a Prognostic Factor in Intrahepatic Cholangiocarcinoma
Authors: Shirai Kazuhisa , Ebata Tomoki , Oda Koji , Nishio Hideki , Nagasaka Tetsuro , Nimura Yuji , Nagino Masato 
Published: September 2008

AbstractBackgroundPerineural invasion is commonly observed in biliary tract cancer and is an independent prognostic factor. Since intrahepatic cholangiocarcinoma (ICC) develops from biliary epithelia in the liver, ICC may share the same characteristics in terms of the prognostic implications of perineural invasion. The aim of this study was to evaluate the clinical significance of perineural invasion in ICC.MethodsA total of 59 patients with ICC who underwent hepatectomy were retrospectively reviewed. The numbers of nerves with and without tumor involvement were counted. The perineural invasion index (PNI) was calculated as the number of involved nerves divided by the total number of nerves examined. Predictors for perineural invasion and prognostic factors were analyzed.ResultsPerineural invasion was observed in 47 of 59 (80%) patients, and the median PNI was 0.082. The macroscopic tumor appearance and tumor location were significantly associated with perineural invasion (p = 0.013 and 0.032, respectively). Univariate and multivariate analyses (excluding seven in‐hospital deaths) revealed that histologic grade, the presence of perineural invasion, nodal metastasis, and intrahepatic metastasis were independent prognostic factors. The survival rate of the patients with (n = 42) or without (n = 10) perineural invasion was 17 and 80% at 3 years; and 17 and 70% at 5 years, respectively (p = 0.001).ConclusionPerineural invasion is frequently found in patients with ICC and is an independent prognostic factor. ICC is an aggressive tumor similar to other biliary tract cancers. Because perineural invasion is a histologic marker of aggressiveness, it potentially has a role as a determinant of patient selection for adjuvant therapy.
The Use of Magnetic Anchors in the Bowel Lumen for Laparoscopic Anterior Resection of Rectosigmoid Colon in Pigs: with Video
Authors: Kume Makoto , Miyazawa Hideaki , Iwasaki Wataru , Abe Fukumitsu , Uchinami Hiroshi , Yamamoto Yuzo 
Published: September 2008

AbstractBackgroundThis article describes a new technique for retracting the rectum upward during laparoscopic surgery using the pulling force created between two magnets.MethodsA magnet and a colonoscope were inserted into the rectal cavity of a swine model, and a second magnet was placed on the abdominal wall creating a magnetic anchor or retraction that pulled the rectum upward. Subsequently, a laparoscopic anterior resection of the rectosigmoid colon was performed. The magnetic anchor transferred an electromagnetic force through the abdominal wall, creating effective organ retraction without the need of a trocar.ResultsSurgery without the use of trocars allows for increased flexibility in the angle, distance, and location of the retraction. Since retraction was achieved without a shaft device that can impede visibility within the abdominal cavity, the surgeons achieved excellent endoscopic views. Because the intraluminal magnetic anchor was placed directly on the inside wall of the target organ, tracking target organ movement closely with the movement of the extracorporeal control magnet was possible and synchronizing their movements was not difficult.ConclusionThe technique presented in this article might be less invasive and could provide more effective manageability for laparoscopic surgery.
Pheochromocytoma in MEN 2A Syndrome. Study of 54 Patients
Authors: Rodriguez Jose M. , Balsalobre Maria , Ponce Jose L. , Ríos Antonio , Torregrosa Nuria M. , Tebar Javier , Parrilla Pascual 
Published: September 2008

AbstractBackgroundPheochromocytoma occurs in nearly 50% of MEN 2A (multiple endocrine neoplasia, type 2A) cases. Many issues related to this tumor are still the subject of debate: the diagnostic management in patients who have had positive genetic study results (RET mutation), variations related to mutation, the best surgical option, and the real relapse rate during long‐term follow‐up. The aim of this study is to present our experience with this unusual disease, looking for answers to some of these questions.Patients and methodsOf 169 patients belonging to 19 MEN 2A families, 54 (32%) presented with pheochromocytoma. The following variables have been studied: (1) clinical and diagnostic data [age, mutation, clinical features, results of catecholamines and catabolites in a 24‐h urine sample, computerized tomography (CT) scan and iodine‐131 meta‐iodobenzylguanidine (MIBG) scintigraphy results, and the means of diagnostic, clinical, or genetic screening]; (2) surgical treatment; and (3) follow‐up and recurrence. The mean follow‐up time was 92.5 months (range: 12–120 months).ResultsThe mean age of the 54 patients was 37.9 years (range: 14–71 years); 33 were women. Most (96.3%) mutations were found in exon 11. The most frequent mutations were Cys634Tyr (in 33 cases [61.1%]) and Cys634Arg (in 14 [25.9%]). The diagnosis of pheocromocytoma was made after the diagnosis of MTC in 26 cases (48.2%), simultaneously in 21 (38.9%), and prior in the 7 remaining cases (12.9%). At the time of diagnosis 28 patients (51.8%) were asymptomatic and 26 (48.2%) had clinical features related to pheochromocytoma. In 6 patients (11.1%), the values of catecholamines and catabolites in urine were normal. In the cases with high values, the most useful isolated determination was that of metanephrines (82%), followed by adrenaline (76%). The CT scan did not provide a correct diagnosis in 6 patients with bilateral lesions, and one patient with a bilateral tumor was not diagnosed by MIBG. The combination of CT scan and MIBG diagnosed 100% of cases. The pheochromocytoma was bilateral in 27 cases, with a total number of 81 pathological glands detected. A laparascopic approach was used in 30 cases and a laparotomy in 24. The mean tumor size was 4.5 cm (range: 1–18 cm). Five patients with unilateral resection relapsed (18.5%), and the mean relapse time was 43.2 months (range: 12–120 months). There was a greater frequency of pheochromocytoma in those subjects who had the Cys634Arg mutation (p < 0.03). In addition, the Cys634Arg mutation is more frequent in bilateral cases. There are no prognostic factors for recurrence.ConclusionsPheochromocytoma in MEN 2A is related to the type of mutation, which can be early onset and is frequently asymptomatic. Its diagnosis requires catecholamines determinations as well as a CT scan. Correct diagnosis of bilaterality is established by CT and MIBG. Laparoscopic adrenalectomy is the treatment of choice.
Incidence of Parathyroid Glands Located in Thymus in Patients with Renal Hyperparathyroidism
Authors: Uno Nobuaki , Tominaga Yoshihiro , Matsuoka Susumu , Tsuzuki Toyonori , Shimabukuro Shuichi , Sato Tetsuhiko , Goto Norihiko , Nagasaka Takaharu , Katayama Akio , Uchida Kazuharu 
Published: September 2008

AbstractBackgroundParathyroid glands are frequently located in thymus, and it is essential to resect thymic tissue from the neck incision, especially in surgery for renal hyperparathyroidism (HPT).MethodsIn this study, we evaluated the incidence, location, and type of intrathymic parathyroid glands in 902 patients who underwent initial parathyroidectomy (PTx) for advanced renal HPT in our department. Removal of the thymic tongues on both sides was routinely performed from the neck incision, and the thymic tissue was carefully examined both macroscopically and microscopically.ResultsOf the 902 patients in the study, 269 had only inferior parathyroid glands in the thymus, in 62 patients only supernumerary glands were found in the thymic tongue, and in 78 patients both inferior and supernumerary glands were present in thymic tissue. Therefore the incidence of patients with intrathymic glands was 45.3% (269 + 62 + 78 = 409/902). In 129 (92.1%) of 140 patients with supernumerary glands in the thymic tongue, these glands were detected only on histopathological examination, and about half of them were classified as the parathyromatosis type.ConclusionsIn the human, parathyroid glands might be located in the thymus in about 50%. If the inferior gland/glands cannot be found around the inferior pole of thyroid lobe, it is very important to search for glands in the thymic tongue. Moreover, to avoid missing supernumerary glands, removal of the thymic tongue on both sides is essential in surgery for renal HPT.