bluuebunny/crossref_metadata_2025 huggingface dataset:
Nanostructure formation during deposition of TiN∕SiNx nanomultilayer films by reactive dual magnetron sputtering
Authors: Söderberg Hans , Odén Magnus , Molina-Aldareguia Jon M. , Hultman Lars
Published: June 2005

Multilayer thin films consisting of titanium nitride (TiN) and silicon nitride (SiNx) layers with compositional modulation periodicities between 3.7 and 101.7 nm have been grown on silicon wafers using reactive magnetron sputtering. The TiN and SiNx layer thicknesses were varied between 2–100 nm and 0.1–2.8 nm, respectively. Electron microscopy and x-ray diffraction studies showed that the layering is flat with distinct interfaces. The deposited TiN layers were crystalline and exhibited a preferred 002 orientation for layer thicknesses of 4.5 nm and below. For larger TiN layer thicknesses, a mixed 111∕002 preferred orientation was present as the competitive growth favored 111 texture in monolithic TiN films. SiNx layers exhibited an amorphous structure for layer thicknesses ⩾0.8nm; however, cubic crystalline silicon nitride phase was observed for layer thicknesses ⩽0.3nm. The formation of this metastable SiNx phase is explained by epitaxial stabilization to TiN. The microstructure of the multilayers displayed a columnar growth within the TiN layers with intermittent TiN renucleation after each SiNx layer. A nano-brick-wall structure was thus demonstrated over a range of periodicities. As-deposited films exhibited relatively constant residual stress levels of 1.3±0.7GPa (compressive), independent of the layering. Nanoindentation was used to determine the hardness of the films, and the measurements showed an increase in hardness for the multilayered films compared to those for the monolithic SiNx and TiN films. The hardness results varied between 18 GPa for the monolithic TiN film up to 32 GPa for the hardest multilayer, which corresponds to the presence of cubic SiNx. For larger wavelengths, ⩾20nm, the observed hardness correlated to the layer thickness similar to a Hall–Petch dependence, but with a generalized power of 0.4. Sources of the hardness increase for shorter wavelengths are discussed, e.g., epitaxial stabilization of metastable cubic SiNx, coherency stress, and impeded dislocation activity.
A full nine-dimensional potential-energy surface for hydrogen molecule-water collisions
Authors: Faure Alexandre , Valiron Pierre , Wernli Michael , Wiesenfeld Laurent , Rist Claire , Noga Josef , Tennyson Jonathan
Published: June 2005

The hydrogen and water molecules are ubiquitous in the Universe. Their mutual collisions drive water masers and other line emission in various astronomical environments, notably molecular clouds and star-forming regions. We report here a full nine-dimensional interaction potential for H2O−H2 calibrated using high-accuracy, explicitly correlated wave functions. All degrees of freedom are included using a systematic procedure transferable to other small molecules of astrophysical or atmospherical relevance. As a first application, we present rate constants for the vibrational relaxation of the υ2 bending mode of H2O obtained from quasiclassical trajectory calculations in the temperature range of 500–4000 K. Our high-temperature (T⩾1500K) results are found compatible with the single experimental value at 295 K. Our rates are also significantly larger than those currently used in the astrophysical literature and will lead to a thorough reinterpretation of vibrationally excited water emission spectra from space.
Estimation of coupling between oscillators from short time series via phase dynamics modeling: Limitations and application to EEG data
Authors: Smirnov D. A. , Bodrov M. B. , Velazquez J. L. Perez , Wennberg R. A. , Bezruchko B. P.
Published: June 2005

We demonstrate in numerical experiments that estimators of strength and directionality of coupling between oscillators based on modeling of their phase dynamics [D. A. Smirnov and B. P. Bezruchko, Phys. Rev. E 68, 046209 (2003)] are widely applicable. Namely, although the expressions for the estimators and their confidence bands are derived for linear uncoupled oscillators under the influence of independent sources of Gaussian white noise, they turn out to allow reliable characterization of coupling from relatively short time series for different properties of noise, significant phase nonlinearity of the oscillators, and nonvanishing coupling between them. We apply the estimators to analyze a two-channel human intracranial epileptic electroencephalogram (EEG) recording with the purpose of epileptic focus localization.
Demonstration of quasi-monoenergetic electron-beam generation in laser-driven plasma acceleration
Authors: Miura Eisuke , Koyama Kazuyoshi , Kato Susumu , Saito Naoaki , Adachi Masahiro , Kawada Yoichi , Nakamura Tatsufumi , Tanimoto Mitsumori
Published: June 2005

The generation of a quasi-monoenergetic electron beam in laser-driven plasma acceleration is reported. A monoenergetic electron beam with an energy of 7 MeV was emitted from a high-density plasma (electron density >1020cm−3) produced by a 2 TW 50 fs laser pulse. The divergence of the monoenergetic beam was ±1.2°. The first Stokes satellite peak of stimulated forward Raman scattering was observed in the spectrum of the light transmitted through the plasma. The plasma wave was excited in the region of which electron density was around 1.3×1020cm−3. The acceleration length was estimated to be 500μm from the length of the side-scattered light image. It is considered that the monoenergetic beam generation is due to the matching of the acceleration length to the dephasing length determined by the velocity difference between the accelerated electrons and the plasma wave.
Interfacial segregation of dopants in fully silicided metal-oxide-semiconductor gates
Authors: Copel M. , Pezzi R. P. , Cabral C.
Published: June 2005

We have investigated the structure of Sb and Al implanted NiSi∕SiO2 interfaces. The addition of dopants has been previously found to alter operating thresholds of silicide-gated field effect transistors. We find that Sb is segregated to an interfacial site, and is in a metallic bonding configuration. In contrast, interfacial Al is in an oxidized state. The two additives would appear to alter the threshold voltages by distinctly different mechanisms.
Bragg grating magnetic photonic crystal waveguides
Authors: Li Rong , Levy Miguel
Published: June 2005

Planar ridge waveguide magnetic photonic crystals are demonstrated. A single-defect photonic band-gap structure, fabricated on (Bi,Lu)3Fe5O12 films by focused ion beam patterning, exhibits photonic band gaps, resonant transmission, and resonant Faraday rotation in the wavelength range from 1480 nm to 1580 nm. A stop band triplet is found. The effects of linear birefringence and modal multiplicity on the optical response of the photonic structure are discussed.
Low-temperature preparation of highly (100)-oriented Pb(ZrxTi1−x)O3 thin film by high oxygen-pressure processing
Authors: Zhang X. D. , Meng X. J. , Sun J. L. , Lin T. , Chu J. H.
Published: June 2005

A method for thin-film fabrication employing high oxygen-pressure processing (HOPP) was developed. With this method, the highly (100) oriented Pb(ZrxTi1−x)O3 (PZT) thin film was fabricated at temperature as low as 400°C. HOPP is compatible to the ferroelectric PZT film integration with a readout integrated circuit. The sol-gel-derived PZT 50∕50 thin film showed a well-saturated hysteresis loop at an applied electric field of 367kV∕cm with Pr and Ec of 45μC∕cm2 and 121kV∕cm, respectively. Large electric leakage was attributed to remnant organic components, which was demonstrated by sputtered organic-free PZT films. The optimized Pr and Ec are of 26μC∕cm2 and 93kV∕cm under an applied electric field of 400kV∕cm.
Enhanced characteristics of an uncooled microbolometer using vanadium–tungsten oxide as a thermometric material
Authors: Han Yong-Hee , Kim Kun-Tae , Shin Hyun-Joon , Moon Sung , Choi In-Hoon
Published: June 2005

To produce a highly sensitive uncooled microbolometer, the development of a high-performance thermometric material is essential. In this work, amorphous vanadium–tungsten oxide was developed as a thermometric material at a low temperature of 300°C, and the microbolometer, coupled with the material, was designed and fabricated using surface micromachining technology. The vanadium–tungsten oxide showed good properties for application to the microbolometer, such as a high-temperature coefficient of resistance of over −4.0%∕K and good compatibility with the surface micromachining and integrated circuit fabrication process due to its low fabrication temperature. As a result, the uncooled microbolometer could be fabricated with high detectivity over 1.0×109cmHz1∕2∕W at a bias current of 7.5μA and a chopper frequency of 10–20Hz.
Study of thermal stability of nickel monogermanide on single- and polycrystalline germanium substrates
Authors: Hsu Shih-Lu , Chien Chao-Hsin , Yang Ming-Jui , Huang Rui-Hao , Leu Ching-Chich , Shen Shih-Wen , Yang Tsung-Hsi
Published: June 2005

We have investigated the thermal stability of nickel monogermanide (NiGe) films formed by rapid thermal annealing on both single- and polycrystalline Ge substrates. We found that the NiGe phase is the only one present after nickel germanidation in the temperature range 400–700°C. A fairly uniform NiGe film formed on the single-crystalline Ge; it possessed excellent resistivity (15.6μΩcm) and was thermally stable up to 550°C, but it degraded rapidly at higher temperatures as a result of agglomeration. In contrast, the NiGe film formed on the polycrystalline Ge exhibited much poorer thermal stability, possibly because of polycrystalline Ge grain growth, which resulted in columnar NiGe grains interlaced with Ge grains that had a dramatically increased sheet resistance. As a result, we observed that the sheet resistances of NiGe lines subjected to annealing at 500°C depended strongly on the linewidth when this width was comparable with the grain size of the polycrystalline Ge.
Phylogenomic Analysis of the Receptor-Like Proteins of Rice and Arabidopsis
Authors: Fritz-Laylin Lillian K. , Krishnamurthy Nandini , Tör Mahmut , Sjölander Kimmen V. , Jones Jonathan D.G.
Published: June 2005

The tomato (Lycopersicon esculentum) Cf-9 resistance gene encodes the first characterized member of the plant receptor-like protein (RLP) family. Other RLPs such as CLAVATA2 and TOO MANY MOUTHS are known to regulate development. The domain structure of RLPs consists of extracellular leucine-rich repeats, a transmembrane helix, and a short cytoplasmic region. Here, we identify 90 RLPs in rice (Oryza sativa) and compare them with functionally characterized RLPs from different plant species and with 56 Arabidopsis (Arabidopsis thaliana) RLPs, including the downy mildew resistance protein RPP27. Many RLPs cluster into four distinct superclades, three of which include RLPs known to be involved in plant defense. Sequence comparisons reveal diagnostic amino acid residues that may specify different molecular functions in different RLP subtypes. This analysis of rice RLPs thus identified at least 73 candidate resistance genes and four genes potentially involved in development. Due to the synteny between rice and other Gramineae, this analysis should provide valuable tools for experimental studies in rice and other cereals.
Chaos, complexity, learning, and the learning organization
Authors: van Eijnatten Frans M. , Putnik Goran D.
Published: June 2005

In order to set the stage for this special issue, the prime concepts are defined: i.e. “chaos,” “complexity,” “learning” (individual and organizational), “learning organization,” and “chaordic enterprise”. Also, several chaos‐and‐complexity‐related definitions of learning and learning organizations are provided. Next, the guest editors' main thesis is presented, namely that the “chaordic enterprise” might be the goal state towards which a company – seen as a learning organization – might evolve, and that the framework of “chaordic systems thinking” could be used as a meta‐model to inform a learning organization which is capable of self‐organization and transformative change under hyper‐turbulent conditions. Finally, in order to illustrate the contours of a chaordic enterprise, the case of a dynamically reconfigurable, globally integrated, networked enterprise is presented.
An antagonistic dialogue about chaordic systems thinking: part I
Authors: Wäfler Toni
Published: June 2005

This paper explores the added value of chaordic systems Thinking for organizational renewal, which is defined as transformation instead of reformation. The exploration is presented in the form of an antagonistic dialogue between two “voices,” which develop commentaries from distinct theoretical inspirations, namely chaordic systems thinking (CST) and socio‐technical systems design (STS). This paper contains part I of the conversation. In the course of the dialogue it becomes obvious that CST both includes and transcends STS, and that it is firmly based in democratic values.
An antagonistic dialogue about chaordic systems thinking: part II
Authors: Wäfler Toni
Published: June 2005

This paper is a continuation of the antagonistic dialogue about the differences of chaordic systems thinking (CST) and socio‐technical systems design (STS). In this second part of the conversation a concrete example is used to illustrate the added value provided by CST. Whereas STS focuses on an organization's surface by designing processes and structures, CST aims at a developed mind and hence at the capability to reflect and understand. It is assumed that consciousness is the basis for the emergence of real organizational novelty, and thus, a prerequisite for viability.
Collective learning
Authors: Backström Tomas
Published: June 2005

A theoretical model of collective learning has been developed based on complex systems theory. The need for collective learning is illustrated by an empirical study of an “unsuccessful” organizational‐renewal project in a Swedish Telecom firm. The conclusion, using chaordic systems thinking as a diagnostic framework, is that its interior was underdeveloped. A suggestion is given for use of collective learning to develop the organizational‐mind domain of the telecom firm in order to make the desired organizational‐behavior change more likely to occur. Collective learning is drawn apart for analytical purposes into four abilities: relationics, correlation, internal model, and praxis. It was possible to operationalize the theoretical model into a questionnaire and the model functioned well when analyzing the answers in a way that could be understood and accepted by the respondents of the questionnaire, and to give a base for work on improvements.
An inquiry into the foundations of organizational learning and the learning organization
Authors: Jensen Jorgen A. , Rasmussen Ole E.
Published: June 2005

People's mental models are viewed as being significant in achieving organizational outcomes, on the assumption that mental models influence people's acts. A fundamental issue in the area of organizational learning, then, is the relation between mental models, learning and performance. We contend that a fruitful line of work is to study persons as exercising competence and enacting qualifications as manifestations of their mental models and relate these to the outcome of their acts. A “case study” of three teams, each with two people, managing a complex, simulated environment is presented, leading to arguments asserting that the quality of thinking and acting correlates positively with the quality of performance. Finally, important, general consequences and implications for improving organizational learning are discussed, as well as specific implications for chaordic systems thinking.
Chaordic systems thinking for learning organizations
Authors: Putnik Goran D. , van Eijnatten Frans M.
Published: June 2005

In this concluding paper the guest editors reflect on the contents of this special issue, and give some suggestions for future use of the CST framework. An interesting disclosure is that in chaos‐and‐complexity research the unit of measurement is not the individual human being, but the collective (i.e. dyad, team, or group), seen as a holon. Another important observation is that human interactions – ranging from the individual to the collective levels – are the “carriers of learning” in CST. In order to guide future research with CST, ten levels of abstraction are delineated which were borrowed from research on general design theory.
Efficacy of modern dressings in the treatment of leg ulcers: A systematic review
Authors: Bouza Carmen , Muñoz Ana , Amate José María
Published: June 2005

Healing of leg ulcers constitutes a major clinical problem. Local methods for accelerating the healing process include modern wound dressings, but it is unclear what impact these dressings have on ulcer healing. This study examines the collective evidence on the effectiveness of modern dressings in the treatment of leg ulcers. To this end, a meta‐analysis was conducted covering randomized clinical trials identified following a systematic review of the literature in different databases. Estimates of effect were calculated according to the fixed effects model. Thirty‐one studies met the inclusion criteria (26 on ulcers of venous etiology, 5 on ulcers of mixed or poorly differentiated etiology). We found no study that exclusively addressed arterial ulcers. Although studies displayed considerable methodological limitations, analysis showed no significant differences in terms of the proportion of healed ulcers or reduction in wound size for both modern and conventional dressings. Similarly, no significant differences were observed between the different modern dressings compared in the studies. Thus, the current medical literature is poor in supporting the use of modern dressings to improve the healing rate of leg ulcers. There is insufficient evidence to determine whether the choice of any specific dressing type affects the healing course of these ulcers. Well‐conducted trials are warranted to reliably address this question.
Diabetic neuropathic foot ulcers and amputation
Authors: Margolis David J. , Allen‐Taylor Lynne , Hoffstad Ole , Berlin Jesse A.
Published: June 2005

A neuropathic foot ulcer is a severe complication of diabetes that can result in a more severe complication, a lower extremity amputation. We conducted a cohort study of 24,616 individuals with a diabetic neuropathic foot ulcer treated within a multicenter wound care network. A total of 1653 (6.7%) individuals had an amputation and 46.3% of these amputations were of a toe or ray (minor amputation). In the more than 10‐year follow‐up period that we studied, the percentage of those who had an amputation varied between 5.6% and 8.4%. Of those who had an amputation, the percentage that had a minor amputation increased over time from 4.0% in the earliest years to more than 60% in the later years of observation. The single most important determinant of amputation was the observation of fascia, tendon, and bone at the initial assessment. In conclusion, about 7% of those with a diabetic neuropathic foot ulcer will have an amputation and in the past 10 years there has been a remarkable increase in the number of minor as compared to major amputations.
Initial report of the use of an injectable porcine collagen‐derived matrix to stimulate healing of diabetic foot wounds in humans
Authors: Marston William A. , Usala Anton , Hill Ronald S. , Mendes Robert , Minsley Mary‐Ann
Published: June 2005

A novel injectable scaffolding matrix (E‐Matrix™) has been developed to accelerate wound healing in diabetic foot ulcers. This porcine collagen‐derived matrix is designed to mimic tertiary embryonic connective tissue and to stimulate fetal wound repair mechanisms including angiogenesis. In vitro and animal studies have indicated a beneficial effect on tissue growth and an acceptable safety profile. In this report, we describe the initial use of this product in a pilot study of six humans with chronic nonhealing diabetic foot ulcers. A dramatic initial response to injection was seen, with an average wound size reduction of 72% 2 weeks after injection. Randomized trials are underway to define the potential benefit of this new treatment modality for diabetic foot ulcers.
Effect of in vitro mechanical compression on Epilysin (matrix metalloproteinase‐28) expression in hypertrophic scars
Authors: Renò Filippo , Sabbatini Maurizio , Stella Maurizio , Magliacani Gilberto , Cannas Mario
Published: June 2005

Epilysin, designated matrix metalloproteinase (MMP)‐28, is the newest member of this family of proteases expressed by keratinocytes in response to an injury. MMP‐28′s physiological role and specific substrates are unknown, but its expression pattern suggests that it may serve a role in both tissue homeostasis and wound healing. The aim of this preliminary study was to observe the presence of MMP‐28 protein in normotrophic and hypertrophic scars and to evaluate the effect of in vitro mechanical compression on its expression. Biopsies from normotrophic and hypertrophic scars resulting from burns were divided into two samples, one to be used as control (uncompressed) and the other to be compressed in an oxygenated organ chamber for 24 hours in the presence of a serum‐free medium, using an electromechanical load transducer (stable pressure = 35 mmHg). Analysis of MMP‐28 protein secretion, assessed by Western blot and β‐casein zymography in scar conditioned media, revealed that normotrophic scar did not release MMP‐28 in any condition while hypertrophic scar released active MMP‐28 both in control conditions and after compression. MMP‐28 immunohistochemistry revealed a light protein presence in normotrophic scar keratinocytes and a strong MMP‐28 positivity in hypertrophic scar keratinocytes in control conditions, while compression increased MMP‐28 staining in normotrophic scar and induced a significant reduction of the protein presence in hypertrophic scar keratinocytes. As it has been suggested that MMP‐28 may restructure the skin basal membrane (Saarialho‐Kere et al., 2002), our data indicate that mechanical compression directly acts to modulate the remodeling phase of wound healing, altering release and activity of MMP‐28 in hypertrophic scars.
Interaction of exogenous liposomal insulin‐like growth factor‐I cDNA gene transfer with growth factors on collagen expression in acute wounds
Authors: Jeschke Marc G. , Schubert Thomas , Krickhahn Mareike , Polykandriotis Elias , Klein Dagmar , Perez‐Polo J. regino , Przkora Rene , Herndon David N.
Published: June 2005

Growth factors have been shown to modulate the complex cascade of wound healing, however, interaction between different growth factors during dermal and epidermal regeneration is still not entirely defined. We have recently shown that exogenous liposomal gene transfer of cDNA results in physiologic expression and response in an acute wound. In the present study we determined the interaction between insulin‐like growth factor‐I (IGF‐I), a mesenchymal growth factor, administered as liposomal cDNA, with other dermal and epidermal growth factors on collagen synthesis in an acute wound. Sprague‐Dawley rats were given a scald burn to inflict an acute wound and divided into two groups to receive weekly subcutaneous injections of liposomes plus a β‐galactosidase containing plasmid (Lac Z [0.2 µg, vehicle]), or liposomes plus the IGF‐I cDNA containing plasmid (2.2 µg) and Lac Z (0.2 µg). Immunological assays, histological and immunohistochemical techniques were used to determine growth factor concentration and different types of collagen (I, III, and IV) after IGF‐I cDNA gene transfer. IGF‐I cDNA transfer accelerated reepithelization and was associated with increased levels of IGF‐I, fibroblast growth factor, keratinocyte growth factor, vascular endothelial cell growth factor, and platelet‐derived growth factor protein expression. IGF‐I cDNA had no effect on transforming growth factor‐β. IGF‐I cDNA significantly increased type IV collagen while it had no effect on types I and III collagen. Exogenously administered IGF‐I cDNA increased protein concentrations of keratinocyte growth factor, fibroblast growth factor, platelet‐derived growth factor, and type IV collagen. We conclude that liposomal IGF‐I gene transfer can accelerate wound healing without causing an increase in types I and III collagen expression.
Hyperoxia improves microvascular perfusion in a murine wound model
Authors: Sheikh Ahmad Y. , Rollins Mark D. , Hopf Harriet W. , Hunt Thomas K.
Published: June 2005

There is a need for a noninvasive method that measures wound angiogenesis. Hyperoxia is known to increase the appearance of new blood vessels in wounds, yet no study has confirmed increases in wound bed perfusion with periodic hyperbaric oxygen (HBO) exposure. This study investigates whether laser Doppler imaging is able to detect and quantify the enhancement of wound angiogenesis that is known to occur with intermittent HBO treatments. Full‐thickness dorsal dermal wounds were created on mice randomized to hyperoxic (n = 14) and control (n = 15) groups. Hyperbaric oxygen was administered twice daily for 90 minutes each at 2.1 atmospheres for 7 days. Wound bed perfusion was measured by laser Doppler imaging on days 0, 7, and 10 postwounding. Wound blood flow increased significantly over baseline on day 7 and 10 in the hyperoxic group, but only on day 10 in the control group. Comparison between groups showed a 20% statistically significant increase in wound perfusion in HBO‐treated animals compared to control on day 10 (p = 0.05). Laser Doppler imaging was able to detect and quantify the increase in wound bed perfusion resulting from intermittent HBO treatments and shows promise as a noninvasive measure of angiogenesis and wound healing.
Wound healing and degradation of the fibrin sealant Beriplast® P following partial liver resection in rabbits
Authors: Kroez Monika , Lang Wiegand , Dickneite Gerhard
Published: June 2005

The objective of this study was to investigate the degradation kinetics of the fibrin sealant (FS) Beriplast® P in an experimental liver surgery model in rabbits. A partial liver resection was performed in 21 rabbits, and the wound area covered with Beriplast® P to ensure hemostasis. Wound healing of the resection sites was evaluated morphologically over 11 weeks. Degradation of the FS was evaluated by measuring the thickness of the remaining fibrin layer. Plasma samples were analyzed for antibodies against fibrinogen, albumin, thrombin, fibrin, and factor XIII. No postoperative hemorrhage was observed, indicating successful hemostasis throughout. The FS was degraded with a half‐life of about 25 days postapplication and was completely replaced by granulation tissue within 9 weeks. The FS degradation and tissue development followed the general stages of wound healing: inflammation and resorption, proliferation, organization and production of collagen, maturation, and scarring. An immune reaction was elicited against the main four human proteins of the FS. The antibody titers peaked on day 14, with a gradual decrease thereafter. We conclude that the FS accomplished hemostasis, facilitated healing in accordance with natural processes, and was completely degraded over time. In humans, the reduced immunogenicity of the FS would potentially increase its degradation half‐life.
Effect of oxidized regenerated cellulose/collagen matrix on dermal and epidermal healing and growth factors in an acute wound
Authors: Jeschke Marc G. , Sandmann Gunther , Schubert Thomas , Klein Dagmar
Published: June 2005

Rapid healing of acute wounds, e.g., in burned patients, can be essential for survival. Oxidized regenerated cellulose/collagen (ORC/collagen) has been shown to improve wound healing of chronic wounds. The aim of the present study was to determine the effect of ORC/collagen on dermal and epidermal healing as well as growth factor concentration in acute wounds. Rats received a full‐thickness excision wound and were treated with either ORC/collagen plus a hydrocolloid dressing or a hydrocolloid dressing alone. Planimetry, immunological assays, histological and immunohistochemical techniques were used to determine dermal and epidermal regeneration, protein concentration, and growth factor concentration. In addition, dermal vascularization and structure were determined. Wounds treated with ORC/collagen showed a significantly faster reepithelization than those treated with hydrocolloid alone, p < 0.05. This accelerated wound healing rate may be explained by significantly higher levels of platelet‐derived growth factor, keratinocyte growth factor, insulin‐like growth factor‐I, and insulin‐like growth factor binding protein‐3 in the ORC/collagen group leading to antiapoptotic effects of skin cells, p < 0.05. There were no significant differences in collagen morphology or deposition, neo‐angiogenesis, or vascular endothelial growth factor concentration between both treatment groups. We conclude that ORC/collagen matrix accelerates epidermal regeneration and locally increases growth factor concentrations. Increased reepithelization was associated with decreased skin cell apoptosis. Based on our data we hypothesize that the ORC/collagen matrix may also have beneficial effects on acute wounds in a clinical setting.
Cell origin in experimental repair of cricoid cartilage defects treated with recombinant human bone morphogenetic protein‐2
Authors: Tcacencu Ion , Carlsöö Bengt , Stierna Pontus
Published: June 2005

We determined the origin of new cartilage and new bone induced by recombinant human bone morphogenetic protein‐2 (rhBMP‐2) at the site of cricoid cartilage defects in rabbits randomly divided into eight groups. The cricoid cartilage was split vertically along the anterior midline and a strip was excised from the anterior part of the cricoid cartilage in all rabbits. The perichondrium from the anterior part of the cricoid cartilage was trimmed off in four groups; two groups treated with rhBMP‐2 and two control groups. In four other groups, the anterior perichondrium was detached and used as a flap with two groups treated with rhBMP‐2 and two groups serving as controls. The rabbits were killed 1 week or 4 weeks after surgery. The larynges were removed, fixed and sectioned, and the sections were stained for light microscopy using various cytochemical and immunological techniques. New cartilage was only present close to the host perichondrium adherent to cricoid cartilage in rabbits treated with rhBMP‐2. New bone was present 4 weeks after surgery, although calcified matrix and alkaline phosphatase activity could be detected at the site of cricoid defects as early as 1 week after surgery. The cell proliferation marker Ki‐67 was strongly expressed in granulation tissue and bone marrow, and it was moderately expressed in muscles adjacent to the cricoid cartilage in rhBMP‐2‐treated specimens. BMP receptors were strongly expressed in cartilage and moderately expressed in adjacent muscles. We conclude that new cartilage originates from the mesenchymal progenitor cells of host perichondrium adherent to cricoid cartilage in rabbits treated with rhBMP‐2. New bone may originate from local muscle.
Dialect stabilization and speaker awareness in non‐native varieties of English1
Authors: Sharma Devyani
Published: June 2005

Research on indigenized non‐native varieties of English has aimed to distinguish these varieties from individual second language learning in structural and social terms (B. Kachru 1983;Platt, Weber and Ho 1984;Cheshire 1991) ; however, quantitative evidence of this divergence remains scarce. Through an analysis of a range of Indian English speakers in a contact situation in the United States, this study distinguishes developing dialect features from second language learning features and explores the concomitant emergence of dialect consciousness. First, an implicational analysis shows that some non‐standard variables (past marking, copula use, agreement) exhibit a second language learning cline while others (articles) form a more stable, incipient non‐standard system shared to some extent by all speakers; a multivariate analysis suggests that both sets of variables are governed by proficiency levels. Next, the explanatory scope of proficiency is assessed by examining the use of selected phonological variants (rhoticity,l‐velarization, aspiration). The use of these features resembles native‐like style‐shifting, as it appears to be more sensitive to speakers’ attitudinal stances than to proficiency levels. This points to the importance of understanding emerging speaker awareness and perceptions of stigma, risk, and value in new varieties of English.
Regulation of oxidative enzyme activity and eukaryotic elongation factor 2 in human skeletal muscle: influence of gender and exercise
Authors: Roepstorff C. , Schjerling P. , Vistisen B. , Madsen M. , Steffensen C. H. , Rider M. H. , Kiens B.
Published: June 2005

Aim:  To investigate gender‐related differences in the responses of oxidative enzymes and eukaryotic elongation factor‐2 (eEF2) to exercise.

Methods:  The influence of exercise (90 min, 60%VO2peak) on citrate synthase (CS) and β‐hydroxyacyl‐CoA dehydrogenase (HAD) activity and mRNA content, together with eEF2 expression and phosphorylation at rest, were assessed in skeletal muscle of untrained (UT) and endurance trained (ET) females and males.

Results:  Citrate synthase and HAD mRNA were higher in females than in males (27% and 48%, respectively, P < 0.05) whereas CS and HAD activity did not differ between females and males (NS). In females only, CS activity was enhanced (P < 0.05) by 90 min exercise. Resting CS mRNA content did not differ between UT and ET but, nevertheless, CS activity was 56% higher in ET than in UT volunteers (P < 0.001). HAD mRNA and activity were not influenced by training status (NS). In UT, CS mRNA was enhanced 37% (P < 0.05) by exercise whereas exercise did not change CS mRNA in ET (NS). eEF2 expression was 31% higher (P < 0.05) and eEF2 Thr56 phosphorylation (which leads to translation inhibition) was 24% lower (P < 0.05) in females than in males. eEF2 expression and phosphorylation were unaffected by training status (NS).

Conclusion:  Basal transcriptional, translational, and/or post‐translational control of CS and HAD seems to be gender‐dependent. Also, gender differences in translation and/or post‐translational protein modification of CS occur during exercise. Accordingly, the potential for peptide‐chain elongation, based on eEF2 expression and phosphorylation, appears to be higher in females than in males.
Myocardial interstitial choline and glutamate levels during acute myocardial ischaemia and local ouabain administration
Authors: Kawada T. , Yamazaki T. , Akiyama T. , Shishido T. , Mori H. , Sugimachi M.
Published: June 2005

Aim:  Noradrenaline (NA) uptake transporters are known to reverse their action during acute myocardial ischaemia and to contribute to ischaemia‐induced myocardial interstitial NA release. By contrast, functional roles of choline and glutamate transporters during acute myocardial ischaemia remain to be investigated. Because both transporters are driven by the normal Na+ gradient across the plasma membrane in a similar manner to NA transporters, the loss of Na+ gradient would affect the transporter function, which would in turn alter myocardial interstitial choline and glutamate levels. The aim of the present study was to examine the effects of acute myocardial ischaemia and the inhibition of Na+,K+‐ATPase on myocardial interstitial glutamate and choline levels.

Methods:  In anaesthetized cats, we measured myocardial interstitial glutamate and choline levels while inducing acute myocardial ischaemia or inhibiting Na+,K+‐ATPase by local administration of ouabain.

Results:  The choline level was not changed significantly by ischaemia (from 0.93 ± 0.06 to 0.82 ± 0.13 μm, mean ± SE, n = 6) and was decreased slightly by ouabain (from 1.30 ± 0.06 to 1.05 ± 0.07 μm, P < 0.05, n = 6). The glutamate level was significantly increased from 9.5 ± 1.9 to 34.7 ± 6.1 μm by ischaemia (P < 0.01, n = 6) and from 8.9 ± 1.0 to 15.9 ± 2.3 μm by ouabain (P < 0.05, n = 6). Inhibition of glutamate transport by trans‐l‐pyrrolidine‐2,4‐dicarboxylate (t‐PDC) suppressed ischaemia‐ and ouabain‐induced glutamate release.

Conclusion:  Myocardial interstitial choline level was not increased by acute myocardial ischaemia or by Na+,K+‐ATPase inhibition. By contrast, myocardial interstitial glutamate level was increased by both interventions. The glutamate transporter contributed to glutamate release via retrograde transport.
Effect of cyclopiazonic acid, an inhibitor of the sarcoplasmic reticulum Ca‐ATPase, on skeletal muscles from normal and mdx mice
Authors: Divet A. , Lompré A.‐M. , Huchet‐Cadiou C.
Published: June 2005

Aim:  In this study, we investigated Ca2+ loading by the sarcoplasmic reticulum in skeletal muscle from mdx mice, an animal model of human Duchenne's muscular dystrophy, at two stages of development: 4 and 11 weeks.

Method:  Experiments were conducted on fast‐ (extensor digitorum longus, EDL) and slow‐ (soleus) twitch muscles expressing different isoforms of Ca2+‐ATPase, which is responsible for the uptake of Ca2+ by the sarcoplasmic reticulum.

Results:  In sarcoplasmic reticulum vesicles, the ATP‐dependent activity and sensitivity to cyclopiazonic acid (CPA), an inhibitor of the sarcoplasmic reticulum Ca2+‐ATPase, were similar in mdx and normal EDL muscle. Furthermore, in chemically‐skinned fibres from both normal and mdx muscles, the presence of CPA induced a decrease in Ca2+ uptake by the sarcoplasmic reticulum. However, the sensitivity to CPA was lower in mdx EDL muscle than in normal muscle. In addition, in EDL muscle from 4‐week‐old mdx mice, the expression of the slow Ca2+‐pump isoform (SERCA2a) was significantly increased, without any accompanying change in slow myosin expression. In contrast, the expression and function of the Ca2+‐ATPase in mdx soleus muscles at 4‐ and 11‐weeks of development did not differ from those in age‐matched controls.

Conclusion:  These findings show that in dystrophic muscle, where the Ca2+ homeostasis was perturbed, the Ca2+ handling by the sarcoplasmic reticulum was altered in fast‐twitch muscle, and this was associated with the expression of the slow isoform of SERCA. In these muscles, reduced Ca2+ uptake could then contribute to an elevated concentration of Ca2+ in the cytosol, and also to Ca2+ depletion of the sarcoplasmic reticulum.
Effects of sodium intake on plasma potassium and renin angiotensin aldosterone system in conscious dogs
Authors: Kjolby M. J. , Kompanowska‐Jezierska E. , Wamberg S. , Bie P.
Published: June 2005

Aims:  The operating range of the renin–angiotensin–aldosterone system is ill‐defined. This study quantifies renin–angiotensin–aldosterone system activity as a function of sodium intake.

Methods:  Renin–angiotensin–aldosterone system variables were measured daily after a sudden reduction in sodium intake (3.0–0.5 mmol kg−1 day−1) or at steady states generated by eight levels of sodium intake (0.5–8.0 mmol kg−1 day−1). Potassium intake was 2.79 ± 0.03 mmol kg−1 day−1. Arterial blood pressure was measured invasively. Hormone concentrations were determined by radioimmunoassays. Glomerular filtration rate and plasma volume were determined by standard methods.

Results:  Sudden sodium intake reduction doubled plasma renin activity and angiotensin II, and tripled aldosterone on day 1 with only small non‐significant additional changes on the following days. Different levels of sodium intake did not affect arterial blood pressure, heart rate, and plasma concentrations of sodium, angiotensinogen, atrial natriuretic peptide, vasopressin, glomerular filtration rate and diuresis. With increasing sodium intake, plasma volume increased by 0.47 ± 0.04 mL (kg body mass)−1 (unit increase in Na intake)−1 (P < 0.01), and plasma potassium decreased with the slope −0.038 mm [(mmol Na+ intake) (kg body mass)−1 day−1]−1 (P = 0.001) while plasma renin‐activity, angiotensin II, and aldosterone decreased systematically as expected.

Conclusions:  A step reduction in sodium intake alters renin–angiotensin–aldosterone system activity on day 1 with little further change the subsequent 4 days. Week‐long increases in sodium intake decreases renin–angiotensin–aldosterone system activity, increases plasma volume, and decreases plasma potassium. Isolated decreases in sodium intake increase aldosterone secretion via volume‐mediated action on the renin–angiotensin system and via increases in plasma potassium.
Predicting financial failure: some evidence from new brunswick agricultural co‐ops
Authors: Dietrich Jorge , Arcelus F. J. , Srinivasan G.
Published: June 2005

Abstract**:  Given the essential role co‐ops play in the Canadian economy, the primary purpose of this paper is to develop methods to forecast their likelihood of insolvency. However, investor‐owner firms form the basic unit of analysis of most popular bankruptcy predictors used in Canada. The question is whether the key underlying elements that differentiates the latter from co‐ops justifies deriving specific bankruptcy prediction formulas exclusively for each type of business organization. To that effect, this research evaluates the efficacy of these current predictors and suggests an improved predictor for agricultural co‐operatives.
Une évaluation des effets de la privatisation sur l’accès aux ressources en eau dans les pays en développement
Authors: Sciandra Luisa
Published: June 2005

Resume**:  Dans la plupart des pays en développement, la relative rareté de l’eau s’accompagne d’une détérioration continue de sa qualité. L’article propose quelques réflexions sur l’implication du secteur privé dans la gestion de l’approvisionnement en eau dans les pays en développement. L’analyse se centre principalement sur les implications sociales et les limites afin de vérifier si la privatisation contribue à l’élargissement de l’accès à l’eau. A cette fin, plusieurs exemples de cas sont présentés qui étayent les conclusions présentées dans la dernière section de l’article.
Welfare Effects of Price Integration in Local Public Transport
Authors: Cassone Alberto , Marchese Carla
Published: June 2005

Abstract**:  In metropolitan areas collective transport is often supplied by many firms and in many modes. The paper focusses on the merging of decisions about prices in two market regimes: monopoly and benevolent regulation through Ramsey pricing. The results confirm that centralization entails efficiency gains under monopoly whenever a unique supplier substitutes many firms serving each link of a network. Under benevolent regulation, instead, centralization entails efficiency gains only under certain conditions. Moreover, efficiency improvements under Ramsey pricing involve the introduction of cross subsidies among previous regulatory jurisdictions. Hence some users gain while others lose. Both the theoretical and empirical literature suggest that periphery residents are the main beneficiaries of centralization.
THE BILATERAL J‐CURVE: AUSTRALIA VERSUS HER 23 TRADING PARTNERS
Authors: BAHMANI‐OSKOOEE MOHSEN , GOSWAMI GOUR G. , KUMAR TALUKDAR BIDYUT
Published: June 2005

Several studies have tested the J‐curve phenomenon for Australia using non‐stationary aggregate trade data and have provided mixed results. They not only suffer from the ‘aggregation bias problem’ but also from the ‘spurious regression problem’. To overcome these problems, in this paper we investigate the short‐run and the long‐run effects of real depreciation of the Australian dollar on the trade balance between Australia and each of her 23 trading partners using quarterly data over the 1973–2001 period and recent advances in cointegration analysis. The results from the bound testing approach for cointegration and error‐correction modeling does not provide much support for the J‐curve phenomenon.
STRATEGIC DEBT AND RJV COMPETITION*
Authors: CHEN HO‐CHYUAN
Published: June 2005

Firms first choose their debt level, next form an RJV and choose R&D investment, and then choose output in Cornot competition. Through the use of debt, a firm commits an aggressive stance, a higher output level, and higher R&D investment, whereby the latter helps solve the free‐riding problem that usually exists in R&D studies. However, a firm in an unleveraged industry gains the highest profit, while a leveraged firm in an asymmetric industry (which achieves the highest profit in Brander and Lewis (1988)) gains the lowest profit. As a result, both firms using debt and both firms not using debt are the two equilibria, and the latter survives as a focal outcome. This is in sharp contrast to Brander and Lewis who find that both firms using debt is a prisoner's dilemma outcome.
GAUGING THE SOURCES OF GROWTH OF HIGH‐TECH AND LOW‐TECH INDUSTRIES: THE CASE OF KOREAN MANUFACTURING*
Authors: SUN CHIA‐HUNG , KALIRAJAN KALIAPPA P.
Published: June 2005

Literature argues that the source of growth for high‐tech industries emanates from technological progress, while that for low‐tech industries comes from technical efficiency improvement. Also, some empirical studies have shown that technological progress is often accompanied by deterioration in technical efficiency. The focus in this study is to discuss a methodology and test the above two hypotheses with regard to Korean manufacturing data from 1970 to 1997. The study found that the 2.5 per cent average annual rate of technological progress during this period was the major contributor to total factor productivity (TFP) growth in Korean manufacturing whereas technical efficiency grew by a modest 1.1 per cent per annum. The analysis also showed that technological progress was responsible for TFP growth in both high‐tech and low‐tech industries and that both technological progress and technical efficiency improvement co‐existed in the case of Korean manufacturing industries.
INFLATION UNCERTAINTY AND GROWTH: EVIDENCE FROM PANEL DATA*
Authors: APERGIS NICHOLAS
Published: June 2005

This paper explores empirically the link between inflation uncertainty and economic growth through a panel data analysis with a data set from OECD economies that covers the period from 1969 to 1999 and the GARCH methodology. The main results point out that inflation uncertainty has an adverse impact on economic growth in the majority of the cases under investigation
ACCLIMATION OF NITRATE UPTAKE BY PHYTOPLANKTON TO HIGH SUBSTRATE LEVELS1
Authors: Collos Yves , Vaquer André , Souchu Philippe
Published: June 2005

A literature review of data on nitrate uptake by phytoplankton suggests that nitrate levels above 20 μmol N·L−1generally stimulated uptake rates in cultured unicellular algae and natural phytoplankton communities. This phenomenon indicates that phytoplankton cells acclimate to elevated nitrate levels by increasing their uptake capacity in a range of concentrations previously considered to be saturating. Cyanobacteria and flagellates were found to present a considerable capacity for acclimation, with low (0.1–2 μmol N·L−1) half‐saturation values (Ks) at low (5–20 μmol N·L−1) substrate levels and high (1–80 μmol N·L−1) Ksvalues at high (30–100 μmol N·L−1) substrate levels. However, some diatom genera (Rhizosolenia,Skeletonema,Thalassiosira) also appeared to possess a low affinity nitrate uptake system (Ksbetween 18 and 120 μmol N·L−1), which can help resolve the paradox of their presence in enriched seas. It follows that present models of nitrate uptake can severely underestimate the effects of high nitrate concentrations on phytoplankton dynamics and development. A more adequate approach would be to consider the possibility of multiphasic uptake involving several phase transitions as nitrate concentrations increased. Because it is a nonlinear phenomenon featuring strong thresholds, this effect appears to override that of other variables, such as irradiance, temperature, and cell size. Within the present context of eutrophication and for a range of concentrations that is becoming more and more ecologically relevant, equations are tentatively presented as a first approach to estimate Ksfrom ambient nitrate concentrations.