bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isotopic evidence for the provenance and turnover of organic carbon by soil microorganisms in the Antarctic dry valleys
Authors: Hopkins D. W. , Sparrow A. D. , Gregorich E. G. , Elberling B. , Novis P. , Fraser F. , Scrimgeour C. , Dennis P. G. , Meier‐Augenstein W. , Greenfield L. G. 
Published: December 2008

SummaryThe extremely cold and arid Antarctic dry valleys are one of the most environmentally harsh terrestrial ecosystems supporting organisms in which the biogeochemical transformations of carbon are exclusively driven by microorganisms. The natural abundance of 13C and 15N in source organic materials and soils have been examined to obtain evidence for the provenance of the soil organic matter and the C loss as CO2 during extended incubation (approximately 1200 days at 10°C under moist conditions) has been used to determine the potential decay of soil organic C. The organic matter in soils remote from sources of liquid water or where lacustrine productivity was low had isotope signatures characteristic of endolithic (lichen) sources, whereas at more sheltered and productive sites, the organic matter in the soils that was a mixture mainly lacustrine detritus and moss‐derived organic matter. Soil organic C declined by up to 42% during extended incubation under laboratory conditions (equivalent to 50–73 years in the field on a thermal time basis), indicating relatively fast turnover, consistent with previous studies indicating mean residence times for soil organic C in dry valley soils in the range 52–123 years and also with recent inputs of relatively labile source materials.
Methanogenic community composition and anaerobic carbon turnover in submarine permafrost sediments of the Siberian Laptev Sea
Authors: Koch Katharina , Knoblauch Christian , Wagner Dirk 
Published: December 2008

SummaryThe Siberian Laptev Sea shelf contains submarine permafrost, which was formed by flooding of terrestrial permafrost with ocean water during the Holocene sea level rise. This flooding resulted in a warming of the permafrost to temperatures close below 0°C. The impact of these environmental changes on methanogenic communities and carbon dynamics in the permafrost was studied in a submarine permafrost core of the Siberian Laptev Sea shelf. Total organic carbon (TOC) content varied between 0.03% and 8.7% with highest values between 53 and 62 m depth below sea floor. In the same depth, maximum methane concentrations (284 nmol CH4 g−1) and lowest carbon isotope values of methane (−72.2‰ VPDB) were measured, latter indicating microbial formation of methane under in situ conditions. The archaeal community structure was assessed by a nested polymerase chain reaction (PCR) amplification for DGGE, followed by sequencing of reamplified bands. Submarine permafrost samples showed a different archaeal community than the nearby terrestrial permafrost. Samples with high methane concentrations were dominated by sequences affiliated rather to the methylotrophic genera Methanosarcina and Methanococcoides as well as to uncultured archaea. The presented results give the first insights into the archaeal community in submarine permafrost and the first evidence for their activity at in situ conditions.
Fifty‐two‐week efficacy and safety of vildagliptin vs. glimepiride in patients with type 2 diabetes mellitus inadequately controlled on metformin monotherapy
Authors: Ferrannini E. , Fonseca V. , Zinman B. , Matthews D. , Ahrén B. , Byiers S. , Shao Q. , Dejager S. 
Published: December 2008

Aim:  To examine the efficacy and safety of vildagliptin vs. glimepiride as add‐on therapy to metformin in patients with type 2 diabetes mellitus in a 52‐week interim analysis of a large, randomized, double‐blind, multicentre study. The primary objective was to demonstrate non‐inferiority of vildagliptin vs. glimepiride in glycosylated haemoglobin (HbA1c) reduction at week 52.Methods:  Patients inadequately controlled on metformin monotherapy (HbA1c 6.5–8.5%) and receiving a stable dose of metformin (mean dose 1898 mg/day; mean duration of use 36 months) were randomized 1:1 to receive vildagliptin (50 mg twice daily, n = 1396) or glimepiride (titrated up to 6 mg/day; mean dose 4.5 mg/day, n = 1393).Results:  Non‐inferiority of vildagliptin was demonstrated (97.5% confidence interval 0.02%, 0.16%) with a mean (SE) change from baseline HbA1c (7.3% in both groups) to week 52 endpoint of −0.44% (0.02%) with vildagliptin and −0.53% (0.02%) with glimepiride. Although a similar proportion of patients reached a target HbA1c level of <7% with vildagliptin and glimepiride (54.1 and 55.5%, respectively), a greater proportion of patients reached this target without hypoglycaemia in the vildagliptin group (50.9 vs. 44.3%; p < 0.01). Fasting plasma glucose (FPG) reductions were comparable between groups (mean [SE] −1.01 [0.06] mmol/l and −1.14 [0.06] mmol/l respectively). Vildagliptin significantly reduced body weight relative to glimepiride (mean [SE] change from baseline −0.23 [0.11] kg; between‐group difference −1.79 kg; p < 0.001) and resulted in a 10‐fold lower incidence of hypoglycaemia than glimepiride (1.7 vs. 16.2% of patients presenting at least one hypoglycaemic event; 39 vs. 554 hypoglycaemic events, p < 0.01). No severe hypoglycaemia occurred with vildagliptin compared with 10 episodes with glimepiride (p < 0.01), and no patient in the vildagliptin group discontinued because of hypoglycaemia compared with 11 patients in the glimepiride group. The incidence of adverse events (AEs), serious AEs and adjudicated cardiovascular events was 74.5, 7.1 and 0.9%, respectively, in patients receiving vildagliptin, and 81.1, 9.5 and 1.6%, respectively, in patients receiving glimepiride.Conclusions:  When metformin alone fails to maintain sufficient glycaemic control, the addition of vildagliptin provides comparable efficacy to that of glimepiride after 52 weeks and displays a favourable AE profile, with no weight gain and a significant reduction in hypoglycaemia compared with glimepiride.
On stationarity and ergodicity of the bilinear model with applications to GARCH models
Authors: Kristensen Dennis 
Published: December 2008

Abstract.We establish sufficient conditions for the bilinear time‐series model to be strictly stationary and ergodic in terms of its associated Lyapunov exponent. In two special cases, we verify that the conditions are also necessary. We then use these results to give necessary and sufficient conditions for stationarity of specific generalized autoregressive conditionally heteroskedastic (GARCH) models which can be written as a bilinear model, including linear GARCH, Power GARCH, EGARCH among others. These results generalize the ones found in the studies of, among others, Bougerol and Picard [Journal of Econometrics 52 (1992) 115], Duan [Journal of Econometrics 79 (1997) 97] and Nelson [Econometric Theory 6 (1990) 318]. In many cases, the conditions are weaker than the ones found elsewhere in the literature.
The Size and Structure of the World Mutual Fund Industry
Authors: Ramos Sofia B. 
Published: December 2008

Abstract This paper analyses the mutual fund industry for 20 countries using a new database of more than 50,000 mutual funds. The results suggest that more developed industries provide more benefits to investors as they diversify more internationally, charge lower annual charges and present more product sophistication. The results also have important policy implications by emphasising the role of competition and contestability in industry development. Fewer barriers to entry are positively associated with a larger industry, and concomitantly with more efficiency in terms of returns and fees.
A European Legal Method? On European Private Law and Scientific Method
Authors: Hesselink Martijn 
Published: December 2008

AbstractThis article examines the relationship between European private law and scientific method. It argues that a European legal method is a good idea. Not primarily because it will make European private law scholarship look more scientific, but because a debate on the method of a normative science necessarily has to be a debate on its normative assumptions. In other words, a debate on a European legal method will have much in common with the much desired debate on social justice in European law. Moreover, it submits that, at least after the adoption of the Common Frame of Reference by the European institutions, European contract law can be regarded as a developing multi‐level system that can be studied from the inside. Finally, it concludes that the Europeanisation of private law is gradually blurring the dividing line between the internal and external perspectives, with their respective appropriate methods, in two mutually reinforcing ways. First, in the developing multi‐level system it is unclear where the external borders of the system lie, in particular the borders between Community law and national law. Second, because of the less formal legal culture the (formerly) external perspectives, such as the economic perspective, have easier access and play an increasing role as policy considerations.
Vigilance in Przewalski's gazelle: effects of sex, predation risk and group size
Authors: Li Z. , Jiang Z. , Beauchamp G. 
Published: December 2008

AbstractVigilance in social animals is often aimed at detecting predators. Many social and environmental factors influence vigilance, including sex, predation risk and group size. During the summer of 2007, we studied Przewalski's gazelleProcapra przewalskii, an endemic ungulate to the Qinghai‐Tibet Plateau, to test whether and how these three factors affect vigilance. We distinguished groups consisting of males, mothers with lambs and females without lambs making observations on groups in the presence or absence of nearby predators. We assessed the group‐size effect on vigilance and how this varied with levels of predation risk and sex. Males and mothers scanned longer and with a higher frequency than females without lambs. Individuals were more vigilant under direct predation threat. Although vigilance generally decreased with group size, the extent of the decrease was independent of predation risk and was not significant in males. The results suggest that mothers are more vigilant suggesting greater vulnerability and that males may have increased their vigilance to compete for higher social ranks. The positive correlation between vigilance and predation risk and the negative correlation between vigilance and group size are consistent with earlier findings, but we failed to find an interaction between group size and predation risk on vigilance perhaps because vigilance levels are low even in small groups, thus making similar vigilant upward adjustments in both small and large groups.
Inhibition of Alzheimer’s amyloid toxicity with a tricyclic pyrone molecule in vitro and in vivo
Authors: Hong Hyun‐Seok , Rana Sandeep , Barrigan Lydia , Shi Aibin , Zhang Yi , Zhou Feimeng , Jin Lee‐Way , Hua Duy H. 
Published: December 2008

AbstractSmall β‐amyloid (Aβ) 1–42 aggregates are toxic to neurons and may be the primary toxic species in Alzheimer’s disease (AD). Methods to reduce the level of Aβ, prevent Aβ aggregation, and eliminate existing Aβ aggregates have been proposed for treatment of AD. A tricyclic pyrone named CP2 is found to prevent cell death associated with Aβ oligomers. We studied the possible mechanisms of neuroprotection by CP2. Surface plasmon resonance spectroscopy shows a direct binding of CP2 with Aβ42 oligomer. Circular dichroism spectroscopy reveals monomeric Aβ42 peptide remains as a random coil/α‐helix structure in the presence of CP2 over 48 h. Atomic force microscopy studies show CP2 exhibits similar ability to inhibit Aβ42 aggregation as that of Congo red and curcumin. Atomic force microscopy closed‐fluid cell study demonstrates that CP2 disaggregates Aβ42 oligomers and protofibrils. CP2 also blocks Aβ fibrillations using a protein quantification method. Treatment of 5× familial Alzheimer’s disease mice, a robust Aβ42‐producing animal model of AD, with a 2‐week course of CP2 resulted in 40% and 50% decreases in non‐fibrillar and fibrillar Aβ species, respectively. Our results suggest that CP2 might be beneficial to AD patients by preventing Aβ aggregation and disaggregating existing Aβ oligomers and protofibrils.
CAPACITY BUILDING OF ETHICS REVIEW COMMITTEES ACROSS AFRICA BASED ON THE RESULTS OF A COMPREHENSIVE NEEDS ASSESSMENT SURVEY
Authors: NYIKA ACEME , KILAMA WENCESLAUS , TANGWA GODFREY B. , CHILENGI ROMA , TINDANA PAULINA 
Published: December 2008

ABSTRACTA needs assessment survey of ethics review committees (ERCs) across Africa was conducted in order to establish their major needs and areas of weaknesses in terms of ethical review capacity. The response rate was 84% (31 of 37 targeted committees), and committees surveyed were located in 18 African countries. The majority of the responding committees (61%) have been in existence between 5 and 10 years; approximately 74% of the respondents were institutional committees, with the remainder being either national (6/31) or regional (2/31).In terms of the ethical review process, nine of the 31 committees that responded did not have standard operating procedures (SOPs), and seven of the 22 that did have SOPs had never revised them after their initial development (an average period of three years). Of the 31 committees, 10 operated without any ethical guidelines. Many of the committees (13/30) met once per month, and the number of proposals reviewed annually varied, ranging from five to over 100. All respondents relied on paper‐based data management and archiving systems.Overall, the survey identified the major constraints on ERCs as lack of office equipment, outdated or lack of SOPs, lack of electronic data management systems, inadequate resources, lack of or insufficient expertise on the committees, and poor recognition of the importance of the role of the committees. Consequently, the authors are addressing the identified needs and weaknesses through the Bill and Melinda Gates Foundation‐funded capacity building project. The impact of the intervention project will be assessed during and at the end of the four‐year longitudinal project.
Evaluation of the AHRQ Patient Safety Initiative: Framework and Approach
Authors: Farley Donna O. , Battles James B. 
Published: December 2008

Objective. Describe the evaluation performed of the patient safety initiative operated by the Agency for Healthcare Research and Quality (AHRQ).AHRQ Patient Safety Initiative. When patient safety became a national priority in 2000, Congress charged and funded AHRQ to improve health care safety. Over the next 6 years, AHRQ funded more than 300 research projects and other activities, addressing diverse patient safety issues and practices.The Patient Safety Evaluation. AHRQ contracted with RAND in 2002 to perform a 4‐year evaluation of the initiative, which was completed in 2006. This formative evaluation used the CIPP program evaluation model, which emphasizes multiple stakeholders' interests (e.g., patients, providers, funded researchers). We monitored the progress of the patient safety initiative and provided AHRQ annual feedback that assessed each year's activities, identifying issues and offering suggestions for actions by AHRQ. Given the size and complexity of the initiative, the evaluation needed to examine key individual components and synthesize results across them, and it also had to be responsive to changes in the initiative over time. We used a conceptual framework to bring together the disparate pieces to synthesize overall findings. The remaining articles in this issue describe selected results from this evaluation.
Metamorphic evolution of low‐T eclogite from the North Qilian orogen, NW China: evidence from petrology and calculated phase equilibria in the system NCKFMASHO
Authors: WEI C. J. , YANG Y. , SU X. L. , SONG S. G. , ZHANG L. F. 
Published: December 2008

AbstractLow‐T eclogites in the North Qilian orogen, NW China share a common assemblage of garnet, omphacite, glaucophane, epidote, phengite, quartz and rutile with or without paragonite. Phase relations for the low‐T eclogites can be modelled well in the system NCKFMASHO with the updated solid‐solution models for amphibole and clinopyroxene. Garnet in the eclogite typically exhibits growth zonations in which pyrope increases while grossular somewhat decreases from core to rim, which is modelled as having formed mainly in the P–T conditions of lawsonite‐eclogite facies at the pre‐peak stage. Omphacite shows an increase in jadeite component as aegirine and also total FeO decrease in going from the inclusions in garnet to grains in the matrix, and from core to rim of zoned crystals, reflecting an increase in metamorphic P–T conditions. Glaucophane exhibits a compositional variation in X(gl) (= Fe2+/(Fe2+ + Mg)) and F(gl) (= Fe3+/(Fe3+ + Al) in M2 site), which decrease from the inclusions in garnet to crystals in the matrix, consistent with an increase in P–T conditions. However, for zoned matrix crystals, the X(gl) and F(gl) increase from core to rim, is interpreted to reflect a late‐stage decompression. Using composition isopleths for garnet rim and phengite in P–T pseudosections, peak P–T conditions for three samples Q5–45, Q5–01 and Q7–28 were estimated as 530–540 °C at 2.10–2.25 GPa, 580–590 °C at 2.30–2.45 GPa and 575–590 °C at 2.50–2.65 GPa, respectively, for the same assemblage garnet + omphacite + glaucophane + lawsonite (+ phengite + quartz + rutile) at the peak stage. The eclogites suggest similar P–T ranges to their surrounding felsic–pelitic schists. During post‐peak decompression of the eclogites, the most distinctive change involves the transformation of lawsonite to epidote, releasing large amount of water in the rock. The released fluid promoted further growth of glaucophane at the expense of omphacite and, in appropriate bulk‐rock compositions, paragonite formed. The decompression of eclogite did not lead to pronounced changes in garnet and phengite compositions. Peak P–T conditions of the North Qilian eclogite are well constrained using both the average P–T and pseudosection approaches in Thermocalc. Generally, the conventional garnet–clinopyroxene geothermometer is too sensitive to be used for constraining the temperature of low‐T eclogite because of the uncertainty in Fe3+ determination in omphacite and slight variations in mineral compositions because of incomplete equilibration.
Digital Media and Dematerialization
Authors: Hogg Nick , Jackson Tim 
Published: December 2008

SummaryAdvances in information and communications technologies (ICTs) could, in principle, offer a means of dematerializing a wide variety of services. In practice, however, the material resource impact of electronic equipment is itself an issue of increasing concern. This article looks specifically at music delivery methods to investigate whether digital media and associated hardware can reduce the material throughput attributable to music delivery. In the first part of the article, we examine recent market trends in digital music delivery and digital media sales. Next we report on a series of stakeholder interviews undertaken during 2006 to explore industry views on the relationship among audio content, electronic hardware, and environmental impact. Finally, we carry out a scenario analysis to investigate the potential material impacts of different possible futures in music delivery. Although in one scenario we find some potential for dematerialization, there are too many ambiguities in underlying assumptions about the relationship between content and hardware to predict with any confidence that the promise of digital media will lead to the dematerialization of music delivery. Currently, at least, it appears that digital formats have not contributed to dematerialization, essentially due to increases in hardware. It seems most likely that the material resource impacts of digital music delivery will continue to be significant for some time.
The Effects of Primers and Surface Bonding Characteristics on the Adhesion of Polyurethane to Two Commonly Used Silicone Elastomers
Authors: Chang Paul P. , Hansen Nancy A. , Phoenix Rodney D. , Schneid Thomas R. 
Published: December 2008

Abstract Purpose: When restoring facial defects, maxillofacial prosthodontists and anaplastologists are often limited by material deficiencies. Silicone elastomers bonded to a polyurethane liner best satisfy the functional and esthetic requirements necessary for facial prostheses; however, patients using silicone prostheses with polyurethane liners often experience varying degrees of debonding at the polyurethane–silicone interfaces. This may result in failure of such prostheses. The purpose of this investigation was to evaluate the effects of five primers on bonding between polyurethane and two commonly used silicone elastomers. Material and Methods: Six bonding regimens were used to join polyurethane and silicone materials. Each treatment group consisted of 12 specimens. Bonding regimens included (1) a 40:60 mixture of MDX4‐4210 and Silastic Medical Adhesive Type A, in conjunction with Dow Corning 1205 primer (Udagama's technique); (2) silicone A‐2000 with Dow Corning 1205 primer; (3) silicone A‐2000 with A‐330‐G primer; (4) silicone A‐2000 with Mucopren primer; (5) silicone A‐2000 with Sofreliner T primer; and (6) silicone A‐2000 with Sofreliner MS primer. Following fabrication, specimens were attached to a universal testing machine and separated in tension at a crosshead speed of 25.4 mm/min. One examiner performed the assessment of T‐peel strength (N/mm), peak load (N), and peel distance (mm) for all specimens. Mean data were analyzed using one‐way ANOVA followed by Fisher's protected significant difference multiple comparison of the means (α= 0.05). Results: A statistically significant difference (p < 0.05) in T‐peel strength was found among specimen groups. Post hoc analysis indicated that Sofreliner MS primer (1.32 ± 0.13 N/mm) and Sofreliner T primer (1.25 ± 0.11 N/mm) increased the bond strengths significantly compared to A‐330‐G primer (0.91 ± 0.10 N/mm) and Udagama's technique (0.13 ± 0.02 N/mm). Cohesive failure between silicone A‐2000 and polyurethane liner was observed when Sofreliner MS primer and Sofreliner T were used. Conclusion: Within the limitations of this study, the use of Sofreliner MS primer and Sofreliner T primer produced significant increases in the bond strength of silicone elastomer to polyurethane liner material. Based on T‐peel strength, peel distance, and peak load data, the combination of silicone A‐2000 and Sofreliner MS primer resulted in the greatest mean bond strength for silicone‐to‐polyurethane applications.
Microtensile Bond Strength of Porcelain Laminate Veneers Bonded to Fluorosed Teeth
Authors: Ratnaweera Priyadarshanee M. , Fukagawa Nao , Tsubota Yuji , Fukushima Shunji 
Published: December 2008

Abstract Purpose: The aim of this study was to evaluate the microtensile bond strengths (MTBSs) of porcelain laminate veneers bonded to normal and fluorosed teeth. Materials and Method: Forty human incisors, including 20 normal and 20 moderately fluorosed teeth [Thylstrup Fejerskov Index (TFI) = 4 to 6], were collected. The labial surfaces of the teeth were ground up to 1 mm and polished with #600 silicon carbide abrasive paper. The surfaces were bonded to 1‐mm‐thick ceramic slices (5 × 5 mm2) previously made (VitaVM7) using one of two ceramic cement systems (RelyX or Clapearl) following the manufacturers' instructions. A resin composite was added on top of the ceramic slices and built up to 5‐mm thickness to serve as grips. The specimens were stored in water (37°C) for 24 hours, and beams of adhesive interface with a surface area of ∼1.25 mm2 were obtained. Then the beams were subjected to MTBS tests at a crosshead speed of 1.0 mm/min. The data were analyzed with two‐way ANOVA. Results: The results of the MTBS test (MPa) were 20.55 ± 5.83 (RelyX/fluorosed), 20.16 ± 4.61 (RelyX/normal), 18.74 ± 2.88 (Clapearl/fluorosed), and 21.06 ± 4.99 (Clapearl/normal). There were no significant differences in the MTBSs among the four groups (p > 0.05). Conclusions: The MTBSs of ceramic cement systems used were not influenced by the moderately fluorosed teeth.