bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancement of hydroxyapatite‐mediated three‐dimensional‐like proliferation of mouse fibroblasts by heat treatment: Effects of heat shock‐induced p38 MAPK pathway
Authors: Hiragami Fukumi , Akiyama Junichi , Koike Yoshihisa , Kano Yoshio
Published: July 2005

Regulation of the biocompatibility of compositional hydroxyapatite (HA) with cells is affected by various environmental factors. The aim of this study was to determine whether the p38 mitogen‐activated protein kinase (MAPK) pathway has a key role in enhancement of HA‐mediated three‐dimensional (3D)‐like proliferation of mouse fibroblasts after heat treatment. C3H10T1/2 mouse fibroblasts were cultured with HA granules for 10 weeks after heat treatment at 44°C for 5, 10, 20, and 30 min. The mean rate of formation of 3D‐like proliferation patterns by cells heat treated for 20 min was only 2.1‐fold higher than that by untreated cells, but the mean rates of formation of 3D‐like proliferation patterns by cells heat treated for 5 and 10 min were significantly higher (3.7‐ and 3.3‐fold higher, respectively) than that by untreated cells (p < 0.01). Western blot analysis demonstrated that phosphorylation of p38 MAPK was markedly increased by heat treatment at 44°C for 5 and 10 min. In addition, the activation of heat shock‐induced p38 MAPK was markedly reduced by treatment at 44°C for 30 min. We concluded that 3D‐like proliferation of heat‐treated cells was induced by activation of p38 MAPK. The results of this study should be useful for further studies aimed at elucidation of regulation of the biocompatibility of compositional HA with cells. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
A new GROMOS force field for hexopyranose‐based carbohydrates
Authors: Lins Roberto D. , Hünenberger Philippe H.
Published: July 2005

A new parameter set (referred to as 45A4) is developed for the explicit‐solvent simulation of hexopyranose‐based carbohydrates. This set is compatible with the most recent version of the GROMOS force field for proteins, nucleic acids, and lipids, and the SPC water model. The parametrization procedure relies on: (1) reassigning the atomic partial charges based on a fit to the quantum‐mechanical electrostatic potential around a trisaccharide; (2) refining the torsional potential parameters associated with the rotations of the hydroxymethyl, hydroxyl, and anomeric alkoxy groups by fitting to corresponding quantum‐mechanical profiles for hexopyranosides; (3) adapting the torsional potential parameters determining the ring conformation so as to stabilize the (experimentally predominant) 4C1 chair conformation. The other (van der Waals and nontorsional covalent) parameters and the rules for third and excluded neighbors are taken directly from the most recent version of the GROMOS force field (except for one additional exclusion). The new set is general enough to define parameters for any (unbranched) hexopyranose‐based mono‐, di‐, oligo‐ or polysaccharide. In the present article, this force field is validated for a limited set of monosaccharides (α‐ and β‐D‐glucose, α‐ and β‐D‐galactose) and disaccharides (trehalose, maltose, and cellobiose) in solution, by comparing the results of simulations to available experimental data. More extensive validation will be the scope of a forthcoming article. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 1400–1412, 2005
Increased serum levels of endostatin in patients with idiopathic pulmonary fibrosis
Authors: Sumi Masaaki , Satoh Hiroaki , Kagohashi Katsunori , Ishikawa Hiroichi , Sekizawa Kiyohisa
Published: July 2005

Endostatin is an angiogenesis inhibitor that is an endogenously produced proteolytic fragment of type XVIII collagen. Serum levels of endostatin have been studied extensively in patients with malignant diseases. Recently, elevated serum endostatin levels were observed in patients with systemic sclerosis accompanying pulmonary fibrosis. To determine whether elevated serum endostatin can be observed in patients with idiopathic pulmonary fibrosis (IPF), we measured serum levels of endostatin in 69 patients with benign respiratory disease using an ELISA kit. The median of the serum endostatin levels in these patients was 50.8 pg/mL. Seven of 11 patients (63.6%) with collagen disease‐associated pulmonary fibrosis (CDPF), and 19 of 24 patients (79.2%) with IPF had higher serum endostatin levels than the median level of the 69 patients. There was no statistical difference in serum endostatin levels between the patients with IPF and those with CDPF (P=0.7898). Serum endostatin levels in 24 patients with IPF were significantly higher than those in 34 patients with respiratory diseases other than IPF and CDPF (P=0.0001). Elevated serum levels of endostatin were observed in patients with IPF. Although the mechanisms are unclear, elevated serum levels of endostatin may be related to the fibrosing process in the lung. J. Clin. Lab. Anal. 19:146–149, 2005. © 2005 Wiley‐Liss, Inc.
Will a Marshall Plan for Africa make poverty history?
Authors: Lockwood Matthew
Published: July 2005

A large increase in aid for Africa is a priority for both UK government and non‐governmental organizations (NGOs) in 2005. Despite a history of aid dependence and low growth, there is evidence that aid has a positive effect in Africa. But more aid alone will not produce rapid growth and poverty reduction. Africa's governance record is very poor and attempts at governance reform have largely failed without commitment from leaders. Equally, the policy conditionality debate shows that domestic political considerations have driven the shaping of economic policy, more than donor pressures. The clientelist account of African politics provides a coherent explanation for poor governance, partial and gradual policy change, and also the failure of governance reforms. It also points to a different policy agenda for aid. Copyright © 2005 John Wiley & Sons, Ltd.
Development assistance and development finance: evidence and global policy agendas
Authors: Addison Tony , Mavrotas George , McGillivray Mark
Published: July 2005

Understanding the development effects of official aid is crucial to building a better bridge between research and policy. This paper reviews the current evidence regarding the impact of aid on growth and poverty reduction, and develops a new narrative. In the light of this narrative, the paper then examines aid trends, focusing on the regions of sub‐Saharan Africa and the Pacific. The paper then turns to recent discussion of new and innovative sources of development finance and considers how research has influenced the policy debate through a recent World Institute for Development Economics Research (UNU–WIDER) study for the United Nations (UN) General Assembly. The paper concludes that aid broadly works, that poverty would be higher in the absence of aid, and that the shortfall in aid during the 1990s has, by implication, made it more difficult to meet the Millennium Development Goals (MDGs). Hence, a considerable catch‐up in aid and other development finance flows is now necessary if poverty is to be substantially reduced by 2015. Copyright © 2005 John Wiley & Sons, Ltd.
Efficacy and safety of repeated perioperative doses of recombinant factor VIIa in liver transplantation
Authors: Lodge Peter J. A. , Jonas Sven , Jones Robert M. , Olausson Michael , Mir-Pallardo José , Soefelt Soeren , Garcia-Valdecasas Juan Carlos , McAlister Vivian , Mirza Darius F.
Published: July 2005

Patients undergoing orthotopic liver transplantation (OLT) have excessive blood loss during surgery that requires blood transfusions, leading to increased postoperative morbidity and mortality. We studied the efficacy and safety of activated recombinant factor VII (rFVIIa) in reducing transfusion requirements in OLT. This multicenter, randomized, double-blind, placebo-controlled trial enrolled patients undergoing OLT because of cirrhosis (Child-Turcotte-Pugh class B or C). Patients received a repeated intravenous bolus regimen of rFVIIa 60 or 120 μg/kg or placebo. The primary efficacy endpoint was the total number of red blood cell (RBC) units transfused during the perioperative period. A total of 182 patients were analyzed for efficacy and 183 for safety. No significant effect of rFVIIa was observed on the number of RBC units transfused or intraoperative blood loss compared with the placebo group. A significantly higher number of patients in the rFVIIa study groups avoided RBC transfusion. Administration of rFVIIa but not placebo restored the preoperative prolonged prothrombin time to normal value during surgery. Patients receiving rFVIIa and placebo did not experience a significant difference in rate of thromboembolic events. Additionally, there was no statistically significant effect of rFVIIa treatment on hospitalization rate, total surgery time, and the proportion of patients undergoing retransplantation. In conclusion, use of rFVIIa during OLT significantly reduced the number of patients requiring RBC transfusion. There was no increase in thromboembolic events with rFVIIa administration compared with placebo. (Liver Transpl 2005;11:973–979.)
Stabilization of Enzyme by Exclusive Volume Effect in Hydrophobically Controlled Polymer Microcapsules
Authors: Kim Jin‐Woong , Jung Mi‐Ok , Kim Yong‐Jin , Ryu Jee‐Hyun , Kim Junoh , Chang Ih‐Seop , Lee Ok‐Sub , Suh Kyung‐Do
Published: July 2005

Summary: This communication describes an enzyme stabilization method that allows the use of enzymes irrespective of environmental factors, especially heat, while maintaining their activity for a long time. We have designed enzyme microcapsules that consist of papain enzyme cores, poly(propylene glycol) interlayers, and poly(ε‐caprolactone) walls. By confocal laser scanning microscopy measurements and the thermal stability of papain‐loaded microcapsules, it is demonstrated that the papain is surrounded by a hydrophobic polyol layer and stabilized by the exclusive volume effect. In our study, improved thermal stability can be obtained by using more hydrophobic long‐chained polyols, which is understood to be attributed to the effective formation of a hydrophobic polyol layer between the papain and the polymer wall by means of conformational anchoring in the interface.

(A) A CLSM image of a PCL microcapsule containing FITC‐labeled papain and RBITC‐labeled PPG at the same time. (B) A scheme of the role of hydrophobic polyols in the interface of enzyme and polymer.

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(A) A CLSM image of a PCL microcapsule containing FITC‐labeled papain and RBITC‐labeled PPG at the same time. (B) A scheme of the role of hydrophobic polyols in the interface of enzyme and polymer.
Tailoring of Three‐Phase Crystalline Systems in Isotactic Poly(propylene)
Authors: Obadal Martin , Čermák Roman , Stoklasa Karel
Published: July 2005

Summary: A novel method for the tailoring of unique three‐phase crystalline systems in isotactic poly(propylene) has been proven. It is based on a synergistic application of a specific β‐nucleating agent and high pressure during crystallization. The formation of a γ phase was supported by elevated pressure and high temperature during crystallization; under these conditions the growth of both β and α phases was significantly suppressed. Nevertheless, during the course of crystallization at lower pressure and/or lower temperatures, strong β‐nucleation efficiency favored the formation of a β phase.

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Effects of N‐acetylcysteine on glutathione oxidation and fatigue during handgrip exercise
Authors: Matuszczak Yves , Farid Mehran , Jones Jeffrey , Lansdowne Samme , Smith Melissa A. , Taylor Addison A. , Reid Michael B.
Published: July 2005

Fatigue of hand and forearm muscle groups can limit task performance by astronauts wearing space suits. Countermeasures to delay fatigue would therefore be useful to the space program. N‐acetylcysteine (NAC) has been shown to inhibit fatigue during other tasks so we tested its effects during handgrip exercise. Volunteers practiced isometric handgrip maneuvers until performance was reproducible over three successive sessions (baseline). Performance then was retested after ingesting NAC (150 mg.kg−1) or saline. Drug administration increased NAC and cysteine blood levels (P < 0.001). Performance of sustained maximal efforts was unaffected. During repetitive submaximal efforts, NAC delayed fatigue (130% baseline) and inhibited glutathione oxidation. Saline did not alter glutathione status or performance of sustained maneuvers; repetitive task performance was increased by 15% (P < 0.05), a placebo effect. These data indicate that NAC supports glutathione homeostasis in exercising humans and may delay muscle fatigue during repetitive handgrip exercise. Our findings support oxidative stress as a causal factor in human muscle fatigue and argue for larger translational studies to define NAC effects on human performance. Muscle Nerve, 2005
Pulmonary function tests and blood gases in worsening myasthenia gravis
Authors: Thieben Mark J. , Blacker David J. , Liu Peter Y. , Harper C. Michel , Wijdicks Eelco F. M.
Published: July 2005

The aim of this study was to determine whether pulmonary function tests have a role in predicting the need for ventilation support in myasthenia gravis. Medical records were reviewed for 42 patients with severe myasthenia gravis who required 55 admissions to the intensive care unit. Patients with a vital capacity of more than 20 ml/kg, a maximal expiratory pressure more than 40 cm H2O, or a maximal inspiratory pressure more negative than −40 cm H2O are unlikely to require mechanical ventilation. A decline of 30% or more in maximal inspiratory pressure predicted a group at higher risk of requiring mechanical or noninvasive ventilation. Hypercapnia was frequent and was more common in patients who required mechanical ventilation. Worsening of these pulmonary function and blood gas values in patients with myasthenia gravis may guide decisions about intubation and ventilatory support. Muscle Nerve, 2005
Desmoglein 2 is expressed abnormally rather than mutated in familial and sporadic gastric cancer
Authors: Biedermann Karin , Vogelsang Holger , Becker Ingrid , Plaschke Susanne , Siewert Jörg Rüdiger , Höfler Heinz , Keller Gisela
Published: July 2005

Alterations of the cell adhesion molecule E‐cadherin have been demonstrated in sporadic and hereditary gastric carcinomas. A cell adhesion molecule with functional similarity to E‐cadherin is desmoglein 2 (Dsg2), a major component of the desmosomes. In this study, we investigated whether alterations of Dsg2 are involved in gastric carcinogenesis and whether germline mutations contribute to a genetic predisposition in familial gastric cancer patients with no germline mutations in the E‐cadherin gene. Seventy‐five formalin‐fixed, paraffin‐embedded tissues from 37 familial and 38 sporadic gastric carcinomas were analysed for Dsg2 expression by immunohistochemistry. DNA from 31 familial gastric cancer patients was analysed for germline mutations and five sporadic tumours were analysed for somatic mutations by DHPLC. Of the 75 tumours, 25 (33%) demonstrated abnormal (reduced and/or non‐membrane‐associated) Dsg2 expression. There was a trend towards more frequent abnormal expression in diffuse type (42%) than in intestinal type tumours (18%) (p = 0.066). One germline missense variant leading to a non‐conservative amino acid change (c. 2810 C > A, Thr 937 Asn) was found in a familial gastric cancer patient with a diffuse type tumour. No somatic mutations were identified. The observed abnormal expression of Dsg2 protein suggests that this molecule is involved in the carcinogenesis of a subset of gastric carcinomas, in particular of the diffuse type. Somatic mutations in the gene do not seem to be a very frequent inactivation event and the finding of no clear pathogenic germline mutation rules out Dsg2 as a major gastric cancer predisposition gene. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Co‐expression of c‐kit and stem cell factor in primary and metastatic nasopharyngeal carcinomas and nasopharyngeal epithelium
Authors: Sheu Lai‐Fa , Lee Wen‐Cheng , Lee Herng‐Sheng , Kao Woei‐Yau , Chen Ann
Published: July 2005

Expression of c‐kit has been demonstrated in 33% of adult nasopharyngeal carcinomas (NPCs) and in 88% of paediatric NPCs. Patients with tumours expressing c‐kit tend to exhibit better survival, but a paracrine/autocrine function for the stem cell factor (SCF)/c‐kit system in nasopharyngeal carcinomas has not been reported. This study evaluated the expression of c‐kit and SCF by immunohistochemical staining of nasopharyngeal epithelium (NPE) and of primary and metastatic NPCs. In addition, c‐kit and SCF expression were studied in HONE‐1 NPC cells by immunoprecipitation and western blotting. Expression of c‐kit and SCF was detected in 75% and 57% of NPE, respectively, and there was 48% co‐expression. In primary NPCs, 86% expressed c‐kit, 69% had SCF expression, and there was 67% co‐expression. In metastatic NPCs, 76% expressed c‐kit, 72% expressed SCF and there was 68% co‐expression. Co‐expression of c‐kit and SCF with tyrosine autophosphorylation of p145c − kit was demonstrated in HONE‐1 NPC cells. In addition, the expression level of c‐kit and its autophosphorylation status was not obviously influenced by the transient co‐expression of Epstein–Barr nuclear antigen 1 (EBNA1) and latent membrane protein 1 (LMP1). Co‐expression of c‐kit and SCF is therefore commonly found in nasopharyngeal epithelium and NPCs, and in HONE‐1 NPC cells with autoactivation possibly independent of the co‐expression of EBNA1 and LMP1. All of these findings suggest that autoactivation of SCF/c‐kit signalling may be a potent regulator of the nasopharyngeal epithelial barrier and of immune function at the nasopharyngeal mucosa surface, and may contribute to the carcinogenesis and progression of NPC. Further molecular analysis is required to evaluate the possibility of treatment with tyrosine kinase inhibitors in NPC, analogous to the treatment of gastrointestinal stromal tumours with STI571. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
First‐trimester screening for Down syndrome with ductus venosus Doppler studies in addition to nuchal translucency and serum markers
Authors: Borrell Antoni , Gonce Anna , Martinez Josep M. , Borobio Virginia , Fortuny Albert , Coll Oriol , Cuckle Howard
Published: July 2005

Objective

To estimate the improvement in screening efficiency when fetal ductus venosus Doppler studies are added to existing first‐trimester Down syndrome screening protocols.

Methods

Statistical modelling was used with parameters derived from prospective ductus venosus studies and from the published literature. The pulsatility index for veins (PIV), was determined in the fetal ductus venosus for 3706 unaffected and 25 Down syndrome pregnancies at 10–14 weeks' gestation. Concurrent nuchal translucency measurement and maternal serum pregnancy associated plasma protein A and free‐β human chorionic gonadotrophin were also measured.

Results

The median PIV in Down syndrome was 1.70 times higher than in unaffected pregnancies (95% confidence interval 1.36–2.12). PIV levels followed an approximately log Gaussian distribution with log10 standard deviations of 0.193 and 0.076 in Down syndrome and unaffected pregnancies. There were no statistically significant correlations between PIV and the other markers. Modelling predicts that for a fixed 5% false‐positive rate, the addition of PIV to nuchal translucency alone will increase the detection rate from 76 to 85%, and combined with serum markers, from 88 to 92%. For a fixed 85% detection rate, the false‐positive rate reduced from 15 to 4.8% and from 3.2 to 1.2% respectively.

Conclusion

Ductus venosus Doppler studies can substantially improve Down syndrome screening efficiency. Copyright © 2005 John Wiley & Sons, Ltd.
Binary copolymerization with full depropagation: A study of methyl methacrylate/α‐methyl styrene copolymerization
Authors: Leamen M. J. , McManus N. T. , Penlidis A.
Published: July 2005

The kinetics of the copolymerization of α‐methyl styrene and methyl methacrylate (MMA) have been revisited for the bulk system. Reactivity ratios and other kinetic parameter estimates based upon a copolymerization model developed by Kruger et al. (Makromol Chemie 1987, 188, 2163–2175) have been determined for a range of temperatures (60–140 °C). An interesting phenomenon has been uncovered, which shows that there is a distinct difference in copolymer composition predicted by the model when compared with experimental data at feed ratios of MMA below a critical value. This deviation also appears to be influenced by the reaction temperature. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3868–3877, 2005
Synthesis of methyl methacrylate, styrene, and isobutylene multiblock copolymers using atom transfer and cationic polymerization
Authors: Toman Luděk , Janata Miroslav , Spěváček Jiří , Vlček Petr , Látalová Petra , Sikora Antonín , Masař Bohumil
Published: July 2005

ABCBA‐type pentablock copolymers of methyl methacrylate, styrene, and isobutylene (IB) were prepared by the cationic polymerization of IB in the presence of the α,ω‐dichloro‐PS‐b‐PMMA‐b‐PS triblock copolymer [where PS is polystyrene and PMMA is poly(methyl methacrylate)] as a macroinitiator in conjunction with diethylaluminum chloride (Et2AlCl) as a coinitiator. The macroinitiator was prepared by a two‐step copper‐based atom transfer radical polymerization (ATRP). The reaction temperature, −78 or −25 °C, significantly affected the IB content in the resulting copolymers; a higher content was obtained at −78 °C. The formation of the PIB‐b‐PS‐b‐PMMA‐b‐PS‐b‐PIB copolymers (where PIB is polyisobutylene), prepared at −25 (20.3 mol % IB) or −78 °C (61.3 mol % IB; rubbery material), with relatively narrow molecular weight distributions provided direct evidence of the presence of labile chlorine atoms at both ends of the macroinitiator capable of initiation of cationic polymerization of IB. One glass‐transition temperature (Tg), 104.5 °C, was observed for the aforementioned triblock copolymer, and the pentablock copolymer containing 61.3 mol % IB showed two well‐defined Tg's: −73.0 °C for PIB and 95.6 °C for the PS–PMMA blocks. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3823–3830, 2005
Electrosyntheses of high‐quality poly(5‐nitroindole) films in boron trifluoride diethyl etherate containing additional diethyl ether
Authors: Xu Jingkun , Zhou Weiqiang , Hou Jian , Pu Shouzhi , Yan Liushui , Wang Jingwu
Published: July 2005

High‐quality poly(5‐nitroindole) (PNP) films were synthesized electrochemically by the direct anodic oxidation of 5‐nitroindole in boron trifluoride diethyl etherate (BFEE) containing additional 10% diethyl ether (EE) (by volume). The addition of EE to BFEE could improve the solubility of the monomer. The oxidation potential onset of 5‐nitroindole in this medium was measured to be only 1.04 V versus a saturated calomel electrode (SCE), which was much lower than that determined in acetonitrile and 0.1 mol L−1 tetrabutylammonium tetrafluoroborate (1.53 V vs SCE). PNP films obtained from this medium showed good electrochemical behavior and good thermal stability with a conductivity of 10−2 S cm−1; this indicated that BFEE containing 10% EE was a suitable medium for the electrosyntheses of PNP films. Structural studies showed that the polymerization of the 5‐nitroindole ring occurred at the 2,3‐position. As‐formed PNP films were thoroughly soluble in the strong polar organic solvent dimethyl sulfoxide and partly soluble in tetrahydrofuran or acetone. Fluorescent spectral studies indicated that PNP was a good green‐light emitter, with excitation and emission wavelengths of 420 and 550 nm, respectively. To the best of our knowledge, this is the first time that nitro‐group‐substituted high‐quality conducting polymer films have been electrodeposited. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3986–3997, 2005
Crosslinked sulfonated polyimide networks as polymer electrolyte membranes in fuel cells
Authors: Sundar Saimani , Jang Wonbong , Lee Choonkeun , Shul Yonggun , Han Haksoo
Published: July 2005

Sulfonated polyimides with tertiary nitrogen in the polymer backbone were synthesized with 1,4,5,8‐naphthalenetetracarboxylic dianhydride, 4,4′‐diaminobiphenyl 2,2′‐disulfonic acid, 2‐bis[4‐(4‐aminophenoxy)phenyl]hexafluoropropane, and diaminoacrydine hemisulfate. They were crosslinked with a series of dibromo alkanes to improve the hydrolytic stability. The crosslinked sulfonated polyimide films were characterized for their thermal stability, ion‐exchange capacity (IEC), water uptake, hydrolytic stability, and proton conductivity. All the sulfonated polyimides had good thermal stability and exhibited a three‐step degradation pattern. With an increase in the alkyl chain length of the crosslinker, IEC decreased as 1.23 > 1.16 > 1.06 > 1.01, and the water uptake decreased as 7.29 > 6.70 > 6.55 > 5.63. The order of the proton conductivity of the crosslinked sulfonated polyimides at 90 °C was as follows: polyimide crosslinked with dibromo butane (0.070) > polyimide crosslinked with dibromo hexane (0.055) > polyimide crosslinked with dibromo decane (0.054). The crosslinked polyimides showed higher hydrolytic stability than the uncrosslinked polyimides. Between the crosslinked polyimides, the hydrolytic stability decreased with an increase in the alkyl chain length of the crosslinker. The crosslinked and uncrosslinked sulfonated polyimides exhibited almost the same proton conductivities. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2370–2379, 2005
New way of presenting the universal calibration of gel permeation chromatography to include macromolecules with very high segment density
Authors: Papanagopoulos Dimitrios
Published: July 2005

The universal calibration of gel permeation chromatography presents deviations when star‐shaped polymers are used, especially when they present high segment density. Polymers presenting high segment density also have higher values of Flory's parameter Φ than the corresponding flexible, linear polymers. This deviation disappears if we express the hydrodynamic volume of the polymers with the quantity [η]M/Φ (where [η] is the intrinsic viscosity and M is the molecular mass) instead of the commonly used quantity [η]M. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2388–2391, 2005
Quantum properties of complete solutions for a new noncentral ring‐shaped potential
Authors: Dong Shi‐Hai , Chen Chang‐Yuan , Lozada‐Cassou M.
Published: July 2005

We propose a new exactly solvable ring‐shaped potential V(r,θ) = −(α/r) + (σ/r2) + β cos2θ/(r2sin2θ). The exact bound‐state solutions are presented explicitly. The creation and annihilation operators are established directly from the normalized radial wave functions. We present two important recurrence relations among the diagonal matrix elements and obtain some explicit expressions of mean values of rk (8 ≥ k ≥ −11). The exact form of continuum states is also obtained analytically. Comments are made on the calculation formula of phase shifts and the analytical properties of the scattering amplitude. It is interesting to find that the exact form of continuum states will reduce to that of the bound states at the poles of the scattering amplitude. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
A bio‐inspired approach for regulating and measuring visco‐elastic properties of a robot arm
Authors: Zollo Loredana , Dipietro Laura , Siciliano Bruno , Guglielmelli Eugenio , Dario Paolo
Published: July 2005

This work focuses on interaction control of robot manipulators in unstructured environments, with special regard for situations of unpredictable contact/noncontact transitions. It is basically addressed to those environments where a high level of robot adaptability is required and no information on the geometry of the environment is available. By pointing out the main limitations of standard interaction control schemes in managing situations of contact/noncontact transitions, this paper proposes a new control solution that is inspired by the biological model of motor control in voluntary movements. It consists of a combination of a feedforward loop and a proportional‐derivative plus gravity compensation control in the feedback loop. The control law is named coactivation‐based compliance control in the joint space since a unique function, called coactivation function, is evaluated for regulating robot visco‐elasticity in an unpredictably variable environment. It resumes the mechanism of adjustable visco‐elastic properties acting on the agonist and antagonist muscles of a human arm. The work also proposes a methodology for evaluating performance of interaction control schemes that is based on stiffness graphical representation through ellipses. The method replicates the experimental setup used in neuroscience to measure stiffness in human limbs. It is regarded as a powerful tool for evaluating robot behavior over space and time, since it allows both a visual representation of stiffness variation during motion and a quantitative measure of robot performance. It is shown how the method can be used to evaluate a control scheme and how it can provide indications to improve a control law. In this paper, an application to the standard compliance control in the joint space and the coactivation‐based compliance control is presented. © 2005 Wiley Periodicals, Inc.
Collision‐free control of robotic manipulators in the task space
Authors: Galicki Mirosław
Published: July 2005

This paper addresses the problem of position control of robotic manipulators in the task space with obstacles. A computationally simple class of task space regulators consisting of a transpose Jacobian controller plus an integral term including the task error and the gradient of a penalty function generated by obstacles is proposed. The Lyapunov stability theory is used to derive the control scheme. Through the use of the exterior penalty function approach, collision avoidance of the robot with obstacles is ensured. The performance of the proposed control strategy is illustrated through computer simulations for a direct‐drive arm of a SCARA type manipulator operating in both an obstacle‐free task space and a task space including obstacles. © 2005 Wiley Periodicals, Inc.
Molecular characterization of the 3‐phosphoglycerate kinase gene (PGK1) from the methylotrophic yeast Pichia pastoris
Authors: de Almeida João Ricardo Moreira , de Moraes Lídia Maria Pepe , Torres Fernando Araripe Gonçalves
Published: July 2005

We report the cloning of the 3‐phosphoglycerate kinase gene (PGK1) from the methylotrophic yeast Pichia pastoris by a PCR approach. The coding sequence of the PGK1 gene comprises 1251 bp with the potential to encode a polypeptide of 416 amino acid residues, which shows high identity to homologous proteins from other yeasts. The promoter region of this gene (PPGK1) contains regulatory cis‐elements found in other PGK1 genes, such as TATA box, CT‐rich block and a heat shock element. In the 3′ downstream region we identified a tripartite element 5′‐TAG–TAGT–TTT‐3′, which is supposed to be important for transcription termination. As in other yeasts, the PGK1 gene from P. pastoris is present as a single‐copy gene. Northern blot analysis revealed that the gene is transcribed as a 1.5 kb mRNA; when cells are grown on glucose the levels of this mRNA are increased two‐fold in comparison to cells grown on glycerol. The transcriptional regulation of this gene by the carbon source was further confirmed when the α‐amylase gene from Bacillus subtilis was placed under the control of PPGK1: higher levels of expression were obtained when cells were grown on glucose as compared to glycerol and methanol. Preliminary results related to the strength of PPGK1 show that it represents a potential alternative to constitutive heterologous expression in P. pastoris. The sequence of the gene has been deposited in GenBank under Accession No. AY288296. Copyright © 2005 John Wiley & Sons, Ltd.
Integrating internal and external dispersal in metacommunity assembly: preliminary theoretical analyses
Authors: Fukami Tadashi
Published: July 2005

Internal dispersal, which occurs among local communities within a metacommunity, and external dispersal, which supplies immigrants from outside the metacommunity, can both have a major impact on species diversity. However, few studies have considered the two simultaneously. Here I report preliminary computer‐simulation results to suggest that internal and external dispersal can interact to influence species richness. Specifically, the results show that internal dispersal did not affect species richness under frequent external dispersal, whereas it enhanced richness in local communities while decreasing richness in metacommunities under infrequent external dispersal. Conversely, external dispersal influenced species richness in local communities more greatly in the absence of internal dispersal than in its presence, while external dispersal did not affect richness in metacommunities regardless of internal dispersal. Furthermore, internal and external dispersal interactively determined the importance of community assembly history in generating and maintaining variation in local community structure. Overall, these results suggest that the two dispersal types can reciprocally provide the context in which each affects species diversity and therefore that their effects cannot be understood in isolation of the other.
Blastocladiella emersonii expresses a centrin similar to Chlamydomonas reinhardtii isoform not found in late‐diverging fungi
Authors: Ribichich Karina Fabiana , Gomes Suely Lopes
Published: July 2005

Centrins are members of the calcium‐binding EF‐hand protein superfamily which can be divided into two subfamilies, probably associated with different functions: one related to Chlamydomonas reinhardtii centrin, CrCenp, and the other, represented by Saccharomyces cerevisiae isoform, ScCdc31p. ESTs encoding the two isoforms (BeCen1 and BeCen3) from the chytridiomycete Blastocladiella emersonii were isolated, and expression of the CrCenp‐type centrin, BeCen1, was analyzed throughout the fungus life cycle. Becen1 mRNA levels increase transiently during sporulation and protein levels present a similar pattern. Immunolocalization studies seem to localize BeCen1 at the basal body zone and in the cytoplasm surrounding the nuclear cap, a zoospore organelle.
Exploring the minimal functional unit of the transporter associated with antigen processing
Authors: Koch Joachim , Guntrum Renate , Tampé Robert
Published: July 2005

TAP, an ABC transporter in the ER membrane, provides antigenic peptides derived from proteasomal degradation to MHC class I molecules for inspection by cytotoxic T lymphocytes at the cell surface so as to trace malignant or infected cells. To investigate the minimal number of transmembrane segments (TMs) required for assembly of the TAP complex based on hydrophobicity algorithms and alignments with other ABC transporters we generated N‐terminal truncation variants of human TAP1 and TAP2. As a result, a 6 + 6 TM core‐TAP complex represents the minimal functional unit of the transporter, which is essential and sufficient for heterodimer assembly, peptide binding, and peptide translocation into the ER. The TM1 of both, core‐TAP1 and core‐TAP2 are critical for heterodimerization of the complex.
Elephants of a Feather? The Role of ‘Justice’ in Canadian and American Cold War Military Interventions
Authors: Butler Michael J.
Published: July 2005

Abstract.The polities of Canada and the United States are purportedly engaged in the process of value convergence; however, with regard to the legitimacy of foreign military intervention, divergence seems a more apt characterization. This research explores whether the current discord between Canada and the US reflects an aberration, or a realization of entrenched normative differences, over what justifies the use of military force. A series of regression models tests the hypothesis that justice considerations prompted the military interventions of both the US and Canada during the Cold War. The results herein fail to confirm this hypothesis, and in the process highlight the ways in which each country employed ‘justice’ selectively in the service of broader foreign policy objectives.

Résumé.Les constitutions politiques des États-Unis et du Canada sont supposées tendre vers des valeurs communes; cependant, en ce qui concerne la reconnaissance de la légitimité des interventions militaires à l'étranger, la divergence semble être une caractérisation plus juste. Cette recherche explore si le désaccord actuel entre les États-Unis et le Canada reflète une certaine aberration ou la réalisation de différences profondément ancrées, concernant la justification de l'utilisation de la force militaire. Une série de modèles régressifs teste l'hypothèse selon laquelle des considérations de justice ont provoqué les interventions militaires des États-Unis et du Canada durant la guerre froide. Les résultats infirment cette hypothèse, et soulignent, en même temps, les façons dont chacun des deux pays a employé la “ justice ” de manière sélective pour servir des objectifs plus vastes de politique extérieure.
Leadership and Uncertainty in Fiscal Restructuring: Ralph Klein and Roy Romanow
Authors: de Clercy Cristine
Published: July 2005

Abstract.In the literature on leadership, the Certainty Axiom holds that leaders exercise leadership through reassuring uncertain citizens. It is thought that policy entrepreneurs particularly must supply much certainty to lead people to adopt new policies. A new theory—the Strategic Manipulation of Uncertainty (SMU) model—challenges this axiom. Its propositions hold that political leaders may strategically address public uncertainty to secure specific objectives. Risk-averse, traditional (“transactional”) leaders communicate more certainty, and less uncertainty, than their transformational counterparts. Risk-acceptant, entrepreneurial (“transformational”) leaders supply less certainty, and more uncertainty, than their transactional counterparts. Testing these hypotheses through analyzing the public speeches of Saskatchewan Premier Roy Romanow and Alberta Premier Ralph Klein supports the SMU model. As a transactional leader, Premier Romanow communicated more certainty, and less uncertainty, than Premier Klein. Premier Klein communicated less certainty, and more uncertainty, than Premier Romanow. The results challenge the utility of the Certainty Axiom and suggest that leaders address citizens' uncertainty strategically, increasing it or reducing it, in pursuit of particular policy objectives.

Résumé.Dans la littérature sur le leadership, l'axiome de la certitude stipule que les dirigeants exercent leur leadership en réassurant les citoyens incertains. On considère que les initiateurs de politiques publiques en particulier doivent transmettre beaucoup de certitude pour convaincre le public d'adopter de nouvelles politiques. Une nouvelle théorie—le modèle de la Manipulation stratégique de l'incertitude—remet en question cet axiome. Ce modèle propose que les dirigeants politiques puissent s'adresser stratégiquement à l'incertitude du public afin d'atteindre des objectifs spécifiques. Les dirigeants traditionnels, prenant peu de risques (“ transactionnels ”), communiquent plus de certitude, et moins d'incertitude, tandis que les dirigeants prenant des risques, entreprenant (“ transformationnels ”), offrent moins de certitude et plus d'incertitude. Ces hypothèses sont testées en analysant les discours publics du Premier Ministre de la Saskatchewan, Roy Romanow et du Premier Ministre de l'Alberta, Ralph Klein. Ceci confirme le modèle. En tant que dirigeant “ transactionnel ”, Roy Romanow était plus rassurant que son homologue, Ralph Klein, en ce qui concerne la restructuration fiscale. Les résultats contestent l'utilité de l'axiome de la certitude et suggèrent que les dirigeants entreprenants peuvent bénéficier de l'incertitude des citoyens.
Shifting Boundaries: Aboriginal Identity, Pluralist Theory and the
Politics of Self-Government
Authors: Dacks Gurston
Published: July 2005

Shifting Boundaries: Aboriginal Identity, Pluralist Theory and the
Politics of Self-Government, Tim Schouls., Vancouver: UBC Press 2003, pp.
xiv, 224

This fine, taut contribution to the sprawling literature on
Aboriginality, identity and self-government in Canada begins with a
critique of what Schouls terms the “difference approach.” This
approach sees the vigour of Aboriginal communal culture as fundamental to
the wellbeing of Aboriginal individuals and nations, and accordingly, the
retention of cultural traits as a basic goal of Aboriginal politics.
Horizontalité et gestion publique.
Authors: Workman Carole
Published: July 2005

Horizontalité et gestion publique., Jacques Bourgault (sous la
direction de), Québec : Les Presses de l'Université
Laval, 2002, 355 p.

Le livre “ Horizontalité et gestion publique ” par
Jacques Bourgault a pour objectif de démontrer que la gestion
horizontale peut prendre diverses formes et évoluer
différemment selon les intervenants, la nature du projet,
l'animation du projet et maints autres facteurs. Ce livre peut se
diviser en trois parties. La première partie présente une
analyse de la gestion horizontale, son émergence et son
évolution, ses différences par rapport à la gestion
de projet et la gestion matricielle, ses étapes dans
l'évolution d'un projet, ses avantages et, finalement,
les questions qui demeurent sans réponses. La deuxième
partie analyse treize projets à gestion horizontale. Chaque projet
fait appel à plusieurs départements ou ministères
fédéraux et démontre l'optimisation du rapport
entre l'allocation de ressources, les contraintes et les objectifs.
L'analyse des projets et la rédaction du rapport correspondant
furent dirigées par un chercheur responsable. Le titre de chacun
des rapports ainsi que le nom du chercheur-auteur sont comme suit :
ECOREGIONAL RESEARCH IN AFRICA: LEARNING LESSONS FROM IITA'S BENCHMARK AREA APPROACH
Authors: DOUTHWAITE B. , BAKER D. , WEISE S. , GOCKOWSKI J. , MANYONG V. M. , KEATINGE J. D. H.
Published: July 2005

Ecoregional research has the potential to help address some of the huge challenges facing agriculture in developing countries by developing technologies that work under different agro-ecological conditions, and the processes by which these technologies can be adapted to work in other areas with similar conditions. The CGIAR system has been developing ecoregional research as a new paradigm for over a decade. In this paper we evaluate one of the most ambitious of these initiatives called the Benchmark Area Approach (BAA) pioneered by the International Institute of Tropical Agriculture. We evaluate the BAA against nine good practice criteria for ecoregional research and finding that the approach is delivering, or has the potential to deliver, on all nine. Many of the lessons learnt from this evaluation will be relevant to current and future attempts to undertake co-ordinated multi-locational research for development.
A Geographical Information System (GIS) study of Triassic vertebrate biochronology
Authors: RAYFIELD E. J. , BARRETT P. M. , McDONNELL R. A. , WILLIS K. J.
Published: July 2005

Geographical Information Systems (GIS) have been applied extensively to analyse spatial data relating to varied environmental issues, but have not so far been used to address biostratigraphical or macroevolutionary questions over extended spatial and temporal scales. Here, we use GIS techniques to test the stability, validity and utility of proposed Middle and Late Triassic ‘Land Vertebrate Faunachrons’ (LVFs), a global biostratigraphical framework based upon terrestrial/freshwater tetrapod occurrences. A database of tetrapod and megafloral localities was constructed for North America and Western Europe that also incorporated information on relevant palaeoenvironmental variables. This database was subjected to various spatial analysis techniques. Our GIS analysis found support at a global level for Eocyclotosaurus as an Anisian index taxon and probably Aetosaurus as a Norian indicator. Other tetrapod taxa are useful biostratigraphical/biochronological markers on a regional basis, such as Longosuchus and Doswellia for Late Carnian time. Other potential index fossils are hampered, however, by taxonomic instability (Mastodonsaurus, Metoposaurus, Typothorax, Paleorhinus, Pseudopalatus, Redondasaurus, Redondasuchus) and/or are not clearly restricted in temporal distribution (Paleorhinus, Angistorhinus, Stagonolepis, Metoposaurus and Rutiodon). This leads to instability in LVF diagnosis. We found only in the western Northern Hemisphere is there some evidence for an Anisian–Ladinian biochronological unit amalgamating the Perovkan and Berdyankian LVFs, and a possible late Carnian unit integrating the Otischalkian and Adamanian.

Megaplants are generally not useful for biostratigraphical correlation in the Middle and Upper Triassic of the study area, but there is some evidence for a Carnian-age floral assemblage that corresponds to the combined Otischalkian and Adamanian LVFs. Environmental biases do not appear to strongly affect the spatial distribution of either the tetrapods or megaplants that have been proposed as index taxa in biostratigraphical schemes, though several examples of apparent environmental bias were detected by the analysis. Consequently, we argue that further revision and refinement of Middle and Late Triassic LVFs is needed before they can be used to support global or multi-regional biostratigraphical correlations. Caution should therefore be exercised when using the current scheme as a platform for macroevolutionary or palaeoecological hypotheses. Finally, this study demonstrates the potential of GIS as a powerful tool for tackling palaeontological questions over extended timescales.
Genetic analysis of stomatal conductance in upland cotton (Gossypium hirsutum L.) under contrasting temperature regimes
Authors: RAHMAN H. U.
Published: July 2005

Stomatal conductance plays an important role in the heat avoidance mechanism of crop plants. Stomatal conductance in cotton is genetically determined and has been shown to be associated with heat resistance and higher yields. Experiments were carried out with six generations (parental, F1, F2 and back crosses) of three upland cotton crosses under heat-stressed and non-stressed greenhouse and field regimes, to understand the inheritance pattern of stomatal conductance as affected by contrasting temperature regimes. The results revealed significant variation for stomatal conductance due to generations and generation×temperature regime interaction in the three crosses. In general, heat stress reduced stomatal conductance and available genetic variability. Temperature regimes exerted a significant effect on the expression of the genes responsible for stomatal conductance. High temperature or heat stress favoured the expression of genes having additive effects, while absence of heat stress favoured those having dominant effects in two of the three crosses evaluated. The third cross showed the opposite reaction. The results suggest that genes controlling stomatal conductance in the parents of the first two crosses (MNH-552, HR109-RT, CIM-448, CRIS-19) were different from those controlling stomatal conductance in FH-900 and N-Karishma, the parents of the third cross. The selection efficiency of stomatal conductance in segregating populations was likely to be affected by the complexity of its inheritance, environmental dependency, and presence of substantial non-allelic and genotype×temperature regime interactions.