bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of CEOs on firm performance
Authors: Mackey Alison 
Published: October 2008

AbstractThe extent to which CEOs influence firm performance is fundamental to scholarly understanding of how organizations work; yet, this linkage is poorly understood. Previous empirical efforts to examine the link between CEOs and firm performance using variance decomposition, while provocative, nevertheless suffer from methodological problems that systematically understate the relative impact of CEOs on firm performance compared to industry and firm effects. This study addresses these methodological problems and reexamines the percentage of the variance in firm performance explained by heterogeneity in CEOs. The results of this study suggest that in certain settings the ‘CEO effect’ on corporate‐parent performance is substantially more important than that of industry and firm effects, but only moderately more important than industry and firm effects on business‐segment performance. Copyright © 2008 John Wiley & Sons, Ltd.
How true is a ‘true’ midsagittal section?
Authors: Wah Y. M. I. , Chan L. W. D. , Leung T. Y. , Fung T. Y. , Lau T. K. 
Published: October 2008

AbstractObjectivesTo study the deviation of presumed midsagittal sections of the fetal head from the true image plane, to compare whether certification (by The Fetal Medicine Foundation (FMF), UK) has an effect on the degree of this deviation, and to investigate the impact of imperfect midsagittal sections on nuchal translucency thickness (NT) measurement.MethodsEight sonographers, four of them FMF‐certified (Group A) and the other four not (Group B), were asked to obtain image sections which they believed to represent true midsagittal sections of the fetal head and neck in five patients each. Three‐dimensional volume datasets were acquired for subsequent analysis. The angle between the falx cerebri and the vertical axis was measured and the effect of this angle on NT measurement was assessed.ResultsThe mean angle of deviation was significantly lower among those who were FMF‐certified (5.7° vs. 14.7°, P < 0.001). The 1.8% underestimation of NT by Group A was not statistically significant (P = 0.76), while in Group B the NT could not be measured when the angle of deviation was 14.7°.ConclusionsFMF‐certified operators obtain a better midsagittal section compared with non‐certified operators. The minor deviation from the true midsagittal section by certified operators has no significant effect on the value of NT measurement. This study could provide a model for operator training and auditing. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Validation of the fetal myocardial performance index in the second and third trimesters of gestation
Authors: Van Mieghem T. , Gucciardo L. , Lewi P. , Lewi L. , Van Schoubroeck D. , Devlieger R. , De Catte L. , Verhaeghe J. , Deprest J. 
Published: October 2008

AbstractObjectivesTo test the validity of the myocardial performance index (MPI) and its components against the more conventional methods of fetal cardiac function assessment: the ejection fraction (EF) for systolic function and the E/A index (ratio of transmitral flow during early (E) ventricular filling to flow during atrial (A) contraction) for diastolic function, both in a normal population and in a population at risk for cardiac failure because of volume overload (recipient fetuses in cases of twin–twin transfusion syndrome (TTTS)).MethodsThe MPI was measured prospectively in addition to more commonly used indices of systolic (EF) and diastolic (E/A index) cardiac function in 117 healthy fetuses (gestational age range, 20–36 weeks) and in 14 fetuses suspected of cardiac failure because of the presence of TTTS. Nomograms were constructed for all variables, and correlations between the MPI, EF and E/A index were assessed. The time taken to obtain the measurements as well as the interobserver and intraobserver variability were determined for the MPI and EF.ResultsIn healthy fetuses, the MPI and EF were independent of gestational age, whereas the E/A index and isovolumetric relaxation time (IRT) increased with gestational age. The MPI correlated inversely with the EF (P < 0.001). The IRT showed a trend towards an inverse correlation with the E/A index (P = 0.10). The mean ± SD time needed to measure the MPI and EF was 140 ± 65 s and 185 ± 187 s, respectively (P = 0.43). Interobserver and intraobserver intraclass correlation coefficients for the MPI were 0.98 (95% CI, 0.85–0.99) and 0.82 (95% CI, 0.14–0.95), respectively; those for the EF were 0.58 (95% CI, − 0.16 to 0.85) and 0.51 (95% CI, − 0.46 to 0.83), respectively; and those for the E/A index were 0.97 (95% CI, 0.88–0.99) and 0.91 (95% CI, 0.66–0.98), respectively. All variables, except ejection time, were significantly different between normal fetuses and those with TTTS.ConclusionsThe MPI is an indicator of the systolic component of fetal left ventricular function that can be easily acquired and reproduced. The MPI is strongly correlated with the EF but shows less interobserver and intraobserver variability. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Use of N‐(N′‐arylamino)maleimides to improve the thermal properties of poly(vinyl chloride) through chemical modification and graft copolymerization
Authors: Abdel‐Naby Abir S. , Al‐Dossary Abeer O. 
Published: October 2008

AbstractThe reaction of poly(vinyl chloride) (PVC) with N‐(N′‐arylamino)maleimide derivatives was studied. The thermal stability of the modified polymer was improved markedly when compared with that of the unmodified polymer. The stability improvement was attributed to the replacement of the labile chlorine atoms by more stable organic groups. The modified polymer also showed a lower extent of discoloration when compared with that of unmodified PVC. In order to introduce a polymeric stabilizer into PVC, the dienophilic monomer was chemically grafted onto the polymeric chains. The mechanism of the chemical modification as well as that of the graft copolymerization are discussed. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers.
Polymer plasticization using supercritical carbon dioxide
Authors: Kusmanto Febe , Billham Mark , Hornsby Peter 
Published: October 2008

AbstractThe plasticizing effect of supercritical CO2 (scCO2) during the extrusion of polymers was investigated. A modified extrusion system was used to demonstrate the viscosity‐reducing effect of scCO2 together with a capability to produce foam‐free extrudate with selected polymers, including poly(vinyl chloride). Samples of extrudate and materials prepared off‐line by using a pressure vessel were characterized by thermal, mechanical, and X‐ray techniques. After gas diffusion from the polymer, there was no long‐term effect on polymer structure and properties. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers.
Effects of alkaline and silane treatments on the water‐resistance properties of wood‐fiber‐reinforced recycled plastic composites
Authors: Cui Yi‐Hua , Lee Stephen , Tao Jie 
Published: October 2008

AbstractThe water‐resistance properties of wood‐fiber‐reinforced recycled plastic composites (WRPCs) prepared from postconsumer high‐density polyethylene (HDPE) and wood fibers from saw mills were studied. Three methods consisting of an alkaline method (AM), a silane method (SM), and a combination of the alkaline and silane methods (ASM) were used to modify the wood fibers. The effects of fiber/matrix mix ratio and surface treatment on the moisture content, thickness swelling, and flexural strength change of the WRPCs, before and after immersion in 60°C water for 8 weeks, were studied and analyzed. The flexural fractured surfaces of the WRPCs before and after immersion in hot water were examined, and the fracture mechanism of the WRPCs was discussed. The results showed that the different surface treatments of the wood fibers had significant effects on the moisture content, thickness swelling, and flexural strength of the WRPCs after a long immersion time in hot water. For WRPCs treated by ASM, the moisture content was the lowest, the thickness swelling was at a minimum, and the flexural strength was the highest. Higher water absorption of composites with fiber treated by the AM or SM methods, as compared to those treated by ASM, could be attributed to the incomplete adhesion and wettability between the wood fibers and the polymer matrix, which may have caused more gaps and flaws at the interface. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers.
Measuring a professional conservation education training program for zoos and wildlife parks in China
Authors: Askue Laurel , Heimlich Joe , Yu Jin Ping , Wang Xiaohong , Lakly Shelly 
Published: October 2008

AbstractDesigned and implemented in 2006, the Academy for Conservation Training (ACT) is a conservation education academy modeled after the Association for Zoos and Aquariums' (AZA) professional conservation education course. ACT incorporates conservation education best practices utilized by AZA‐accredited institutions to provide zoo and wildlife park professionals in China with the skills, knowledge, and tools needed to design, implement, and evaluate effective conservation education programs at their facilities. Initial findings indicate that the ACT model is an effective approach to connect these emerging educators with conservation education best practices. The strongest satisfaction responses in this study were in perceptions of the program preparing the individual for work and in personal development. In terms of the longitudinal survey conducted with ACT graduates after the training, the lowest scoring items were the opportunities to meet other zoo educators in China and the quantity of information provided. The most revealing trend in regards to preparedness in becoming zoo educators was that specific pedagogical skills were those where perceived gain was consistent and strong across all three academies. Zoo Biol 28:447–461, 2009. ©2008 Wiley‐Liss, Inc.
Tool support for learning Büchi automata and linear temporal logic
Authors: Tsay Yih-Kuen , Chen Yu-Fang , Tsai Ming-Hsien , Wu Kang-Nien , Chan Wen-Chin , Luo Chi-Jian , Chang Jinn-Shu 
Published: October 2008

AbstractWe introduce a graphical interactive tool, named GOAL, that can assist the user in understanding Büchi automata, linear temporal logic, and their relation. Büchi automata and linear temporal logic are closely related and have long served as fundamental building blocks of linear-time model checking. Understanding their relation is instrumental in discovering algorithmic solutions to model checking problems or simply in using those solutions, e.g., specifying a temporal property directly by an automaton rather than a temporal formula so that the property can be verified by an algorithm that operates on automata. One main function of the GOAL tool is translation of a temporal formula into an equivalent Büchi automaton that can be further manipulated visually. The user may edit the resulting automaton, attempting to optimize it, or simply run the automaton on some inputs to get a basic understanding of how it operates. GOAL includes a large number of translation algorithms, most of which support past temporal operators. With the option of viewing the intermediate steps of a translation, the user can quickly grasp how a translation algorithm works. The tool also provides various standard operations and tests on Büchi automata, in particular the equivalence test which is essential for checking if a hand-drawn automaton is correct in the sense that it is equivalent to some intended temporal formula or reference automaton. Several use cases are elaborated to show how these GOAL functions may be combined to facilitate the learning and teaching of Büchi automata and linear temporal logic.
Vortex analysis of the periodic Ginzburg–Landau model
Authors: Aydi Hassen , Sandier Etienne 
Published: October 2008

We study the vortices of energy minimizers in the London limit for the Ginzburg–Landau model with periodic boundary conditions. For applied fields well below the second critical field we are able to describe the location and number of vortices. Many of the results presented appeared in [H. Aydi, Doctoral Dissertation, Université Paris-XII, 2004], others are new.

Résumé
Nous étudions les tourbillons des minimiseurs de l'énergie de Ginzburg–Landau en supraconductivité dans la limite de London, et pour des conditions aux limites périodiques. Lorsque le champ magnétique appliqué est petit devant le second champ critique, nous décrivons le nombre et la localisation de ces tourbillons. Certains de ces résultats étaient présents dans [H. Aydi, Doctoral Dissertation, Université Paris-XII, 2004], d'autres sont nouveaux.
Singly periodic solutions of a semilinear equation
Authors: Allain Geneviève , Beaulieu Anne 
Published: October 2008

We consider the solutions of the equation

−ɛ^{2}\mathrm{\Delta }u + u−|u|^{p−1}u = 0

in

S^{1} \times \mathbb{R}

, where

ɛ

and

p

are positive real numbers,

p > 1

. We prove that the set of the positive bounded solutions even in

x_{1}

and

x_{2}

, decreasing for

x_{1}\in\, ]\!−\pi ,0[

and tending to

0

as

x_{2}

tends to

+∞

is the first branch of solutions constructed by bifurcation from the ground-state solution

(ɛ,w_{0}(\frac{x_{2}}{ɛ}))

. We prove that there exists a positive real number

ɛ_{ \star }

such that for every

ɛ\in ]0,ɛ_{ \star }]

there exists a finite number of solutions verifying the above properties and none such solution for

ɛ > ɛ_{ \star }

. The proves make use of compactness results and of the Leray–Schauder degree theory.

Résumé

Nous étudions l'équation

−ɛ^{2}\mathrm{\Delta }u + u−|u|^{p−1}u = 0

dans

S^{1} \times \mathbb{R}

, où

ɛ

et

p

sont des nombres réels strictement positifs,

p > 1

. Nous identifions l'ensemble des solutions

(ɛ,u)

où

u

est une fonction positive, paire en

x_{1}

et

x_{2}

, décroissante en

x_{1}

dans

[−\pi ,0]

et tendant vers

0

quand

x_{2}

tend vers

+∞

, comme la première branche de solutions issue d'une bifurcation à partir de l'état fondamental

(ɛ,w_{0}(\frac{x_{2}}{ɛ}))

. Nous prouvons qu'il existe un réel

ɛ_{ \star }

tel que pour tout

ɛ\in ]0,ɛ_{ \star }]

il y a un nombre fini de solutions vérifiant les propriétés énoncées ci-dessus, et aucune telle solution pour

ɛ > ɛ_{ \star }

. Les preuves utilisent des résultats de compacité et la théorie du degré de Leray–Schauder.
Color Doppler analysis of pelvic arteries following bilateral internal iliac artery ligation for severe postpartum hemorrhage
Authors: Yildirim Yusuf , Gultekin Emre , Kocyigit Ali , Yilmaz Cengiz , Ertopcu Kenan , Arioz Dagistan Tolga 
Published: October 2008

AbstractObjectiveTo compare Doppler blood flow characteristics of the uterine, arcuate, and ovarian arteries of women who underwent bilateral internal iliac artery ligation with those of controls.MethodsThirteen women who underwent bilateral internal iliac artery ligation for severe postpartum hemorrhage (PPH) were matched with 15 healthy women of reproductive age. Transvaginal color and pulsed (duplex) Doppler modes were used to visualize the pelvic arteries. The pulsatility index, the resistance index, the systolic/diastolic blood flow ratio, the peak systolic velocity, and the end‐diastolic velocity were measured.ResultsThe mean age was 26.1 ± 5.2 years in the study group and 27.0 ± 5.4 years in the control group. All participants had regular menstrual periods. There were no significant differences between the groups regarding each of the vascular indices for the uterine, arcuate, and ovarian arteries.ConclusionThese findings are consistent with published data demonstrating that pelvic circulation is not compromised after bilateral internal iliac artery ligation.
Gersonide, le pseudo-Tūsi, et le postulat des paralléles.
Authors: Lévy Tony 
Published: October 2008

Euclid's Elements were translated into Hebrew from Arabic in the 13th century; but precious few of the Arabic commentaries have come down to us in a Hebrew version (al-Fārābī, Ibn al-Hayṯam). Nonetheless, a study of several texts dealing with the Fifth Postulate (the Parallel Postulate) of Book I reveals that the Hebrew authors are greatly indebted to Arabic sources.We shall examine three attempted proofs of the Parallel Postulate. The two attempts by Moses ha-Levi of Seville (13th century) and Alfonso of Valladolid (14th century) are mathematically unconvincing. Nevertheless they are interesting historically: Moses ha-Levi exploits the movement of lines which are infinite in actu; and Alfonso, starting from a critique of Ibn al-Hayṯam and al-Nayrīzī, claims to innovate in the use of the method of superposition.In contrast, Gersonides' attempt (14th century) is a well-articulated series of premises and proofs, including several arguments which we have traced back to the Taḥrīr Uṣūl Uqlīdis of Pseudo-Ṭūsī. We feel it is important to emphasize this relationship, even though it is impossible to establish the route by which these arguments found their way to Gersonides.
Ibn Rušd et lesPremiers Analytiquesd'Aristote: Aaperçu sur un problème de syllogistique modale
Authors: Elamrani-Jamal Abdelali 
Published: October 2008

Ibn Rušd devoted a certain number of works to Aristotle'sPrior Analytics. In a series ofopusculeswritten over a period of twenty years and following upon hisMiddle Commentary on Aristotle's Prior Analytics, he faced a problem particular to the modal syllogism – that of the mood of the conclusion in mixed syllogisms.The problem can be stated as follows: At the beginning of thePrior Analytics, Aristotle established a formal deductive principle – that of universal attribution (Pr. An.I.1.24b26–30). Applied to the modal syllogism, this principle is inadequate as stated. It is too general to be applied in a univocal manner in all modal syllogisms. To preserve a sense of coherence in Aristotle's declarations, the commentators had to interpret it. Presenting the interpretations of the commentators, primarily al-Fārābī and Alexander, on the basis of al-Fārābī'sLarge Commentary on Aristotle's Prior Analytics, Averroes criticizes them. Applied according to Alexander's interpretation, the principle of universal attribution is valid only for modal syllogisms one of whose premises is necessary and the other assertoric; according to al-Fārābī's interpretation, it is verified only when the minor premise is possible. Averroes proposes two preliminary solutions. Either this formal deductive principle must be applied differently according to the modal differences of the minor premises in mixed syllogisms (first solution) or would be used in two ways, generally or in keeping with each mood (second solution). These solutions are not satisfactory, for they call into question the unity and universality of the principle of universal attribution as established by Aristotle. What is the utility, Averroes asks, of a principle which does not hold for all modalities or does not apply to all the premises when thePr. An.ought to furnish formal and universal principles of deduction? And why did Aristotle define the principle of universal attribution without distinguishing its application according to each of the three modal premises? Returning at the end of his career to a literal exegesis of Aristotle's propositions and without harkening back to the earlier solutions, he proposes a theory of making the terms modal (fourth solution) in order to save Aristotle's declarations with respect to the principle of universal attribution and the mood of the conclusion of mixed syllogisms (Pr. An.I. 9.30al5–20). Though formally inadequate, this solution, which had a continued history, proposes a new way of looking at the classification of modal propositions.
Risk of gynecologic cancers in Danish hereditary non‐polyposis colorectal cancer families
Authors: BOILESEN ASTRID ELISABETH BRUUN , BISGAARD MARIE LUISE , BERNSTEIN INGE 
Published: October 2008

AbstractObjective. Women in hereditary non‐polyposis colorectal cancer (HNPCC) families have an elevated risk of endometrial and ovarian cancer. The risk in Lynch syndrome families with known mutations in mismatch repair genes (MMR genes) seems to be higher than in familial colorectal cancer (CRC) families. Data in the Danish HNPCC register on the frequency and lifetime risk of gynecologic cancers were analyzed and the actual surveillance strategy discussed in relation to the results. Design. Register‐based retrospective study. Method. A total of 1,780 at‐risk women were identified and epidemiological, clinical and MMR gene mutation data were retrieved. Results. In a total of 105 cases of endometrial cancer, there was no significant difference in MSH2, MSH6 and MLH1 mutation carrier frequency. Compared to the general population, mutation carriers had a 20 times increase in lifetime risk of endometrial cancer. Lifetime risk was elevated four times in familial CRC families. In these families, frequency was correlated to the pedigree phenotype, with significantly higher frequency demonstrated in Amsterdam II families compared to Amsterdam I families and families suspected of HNPCC. A total of 39 cases of ovarian cancer were identified with a lifetime risk of three to four times the general population. No significant correlation was found between the frequency of ovarian cancer and MMR gene mutation status in the families. Conclusion. The benefit of surveillance concerning gynecological cancers seems to be less well founded in familial CRC families than in Lynch syndrome families. Modifying the surveillance strategy may be relevant in the future, but before changing existing guidelines concerning surveillance, further research is recommended.
Hepatocellular enzyme glutathione S‐transferase alpha and intrahepatic cholestasis of pregnancy
Authors: JOUTSINIEMI TITTA , LEINO RIITTA , TIMONEN SUSANNA , PULKKI KARI , EKBLAD ULLA 
Published: October 2008

AbstractObjective. To evaluate and compare plasma glutathione S‐transferase alpha (GSTA) concentrations in the third trimester of pregnancy in patients with intrahepatic cholestasis of pregnancy (ICP) and in healthy pregnant women.Design. Non‐randomized clinical study.Setting.Maternity unit and Department of Clinical Chemistry, Turku University Central Hospital, Turku, Finland.Population. Twenty‐seven women with ICP and 49 healthy pregnant women.Methods. GSTA concentrations were assessed in plasma samples in the third trimester of pregnancy using an enzyme‐linked immunoassay (HEPKIT™ Alpha, Biotrin, Sinsheim‐Reihen, Germany).Main outcome measures. Plasma GSTA, serum alanine and bile acid concentrations were compared between study and control group. Correlation between plasma GSTA levels and serum alanine aminotransferase and bile acid levels in the ICP patients were tested by Spearman correlation coefficients. Main perinatal outcome was compared between the groups.Results. GSTA concentration in the control group was 1.62 μg/l (range: 0.25–6.1). In the ICP patients, the mean plasma GSTA concentration was 51.0 μg/l (range: 2.1–183.5), the mean serum alanine aminotransferase concentration was 145.70 U/l (range: 6–393) and the mean bile acid concentration was 19.2 μmol/l (range: 3–63). There was a statistically significant correlation in ICP patients between plasma GSTA concentration and serum alanine aminotransferase concentration (r= 0.694,p= 0.0001), but not with serum bile acid concentration. Nor was there any statistically significant correlation between gestational weeks and plasma GSTA concentration in the study group.Conclusion. Plasma GSTA measurements may provide a more sensitive and specific diagnostic tool for diagnosis of ICP than the evaluation of transaminases or bile acid concentrations alone. Further studies are needed to evaluate the role of GSTA in the follow‐up of patients with ICP and its prognostic value for threatening fetal distress in patients with ICP.