bluuebunny/crossref_metadata_2025 huggingface dataset:
Two-layer batch-process of YBa2Cu3Ox bulk superconductors induced by NdBa2Cu3Ox film-seeds
Authors: Yu D. J. , Cheng L. , Peng B. N. , Chen Y. Y. , Xu H. H. , Li H. , Yao X. , Ikuta H.
Published: June 2013

Applying a cost-effective process with a simple one-side-heating furnace, two layers of YBa2Cu3Ox (YBCO) bulks were successfully grown in one batch by using NdBa2Cu3Ox (NdBCO) thin-film-seeds deposited on MgO substrates. Due to the large temperature difference between the two layers, the seed-induced growth began at the bottom layer much later than that at the top layer. Remarkably, NdBCO films on the bottom layer samples survived a long time (over 15 h) above the growth temperature and effectively induced the YBCO growth. The significant thermal stability of the films, i.e., the tolerance for a long holding time on the surface of the molten pellet, is supposed to relate to a competition between the dissolution/diffusion of film materials into the liquid and NdBCO grain coarsening/Nd-YBCO crystallization.
Micromagnetic study of novel domain wall motion modes in bilayer nanowire with low saturation magnetization
Authors: Ooba A. , Komine T. , Sugita R.
Published: June 2013

In this study, the effect of the magnetostatic interaction in the bilayer nanowires with perpendicular magnetic anisotropy and low saturation magnetization on the current-induced domain wall motion has been investigated by using micromagnetic calculation. The bilayer nanowire, which consists of continuous layer (CL) and granular layer (GL), is used, and the saturation magnetization in each layer is varied. As a result, domain walls in CL and GL move together as the domain wall structure and the velocities vary. The domain wall motion in bilayer nanowires can be divided into two modes. In one mode, the velocity of domain wall varies when the domain wall structure switches between Bloch and Néel walls. In the other mode, the velocity of domain wall varies when the domain wall structure switches between 90° and 270° of Néel walls. Moreover, the critical current velocity, which corresponds to the spin transfer velocity in the bilayer nanowires, increases with increasing saturation magnetization of the continuous layer and the granular layer. This is because the total energy difference which is the energy difference between two extreme values in total energy as a function of magnetization angle at wall and is proportional to the hard-axis anisotropy energy increases with increasing saturation magnetization of the continuous layer and the granular layer.
Magnetic properties and exchange bias effect of the layered manganese oxychalcogenides La2O3Mn2Se2
Authors: Xie L. , Zhang H. G.
Published: June 2013

The magnetic properties and exchange bias effect is investigated in the polycrystalline sample La2O3Mn2Se2 synthesized by conventional solid-state reaction. The susceptibility data show a broad maximum near 260 K, indicating the existence of two-dimensional short-range ordering in this compound. The sharp cusp in the zero field-cooled susceptibility at about 162 K signifies the antiferromagnetic (AFM) phase transition, and the upturn means the existence of the weak ferromagnetic (FM) magnetization. Moreover, the temperature dependence of the Laudé g-factor obtained by the electron spin resonance spectrum shows a sharp upturn at about 165 K close to the Néel temperature TN determined by the susceptibility measurement. These results further demonstrate the coexistence of the AFM and FM magnetization in the compound. Through measuring the hysteresis loops, a large exchange bias effect is observed in the compound implying the potentially technological applications of La2O3Mn2Se2. The exchange coupling at the FM/AFM interface is responsible for the exchange bias phenomena.
Fracture properties of a cylindrical superconductor with a central cross crack
Authors: Feng W. J. , Gao S. W. , Liu L. L.
Published: June 2013

In this work, the central cross crack problem is investigated for a long cylindrical high-temperature superconductor under electromagnetic forces. The distributions of both the current density and the magnetic flux density in the cylinder are obtained analytically in either the Bean or the Kim critical state model for both the zero-field cooling and the field cooling magnetization processes. Based on the finite element method, lots of the stress intensity factors at the crack tips for decreasing magnetic fields are numerically calculated. Numerical results obtained show that the field cooling activation process has more significant influence on the stress intensity factors than the zero-field cooling activation process, and that for every activation process, as the applied field decreases, the superconducting cylinder is most dangerous when the currents in the crack region are just be influenced. The safety of the superconducting cylinder with a cross crack depends on not only the magnetic process but also the crack length. Additionally, the introduced dimensionless parameter p in the Kim model has different effects on the stress intensity factors obtained from the most dangerous field and from the trapped field. The present study should be helpful to the design and application of high-temperature superconductors.
Helicity dependent photocurrent enabled by unpolarized radiation in a GaAs/Al0.3Ga0.7As two-dimensional electron system
Authors: Ma Hui , Jiang Chongyun , Liu Yu , Yu Jinling , Chen Yonghai
Published: June 2013

We report the experimental observation of photo-assisted generation of helicity dependent photocurrents (PA-HDPC) in a GaAs/Al0.3Ga0.7As two-dimensional electron gas, which is distinct from the circular photogalvanic effect (CPGE). The PA-HDPC is generated under suppressed configuration of CPGE with the illumination of an obliquely incident unpolarized radiation in the system of C2v point group symmetry. We suggest that the PA-HDPC originates from spin-orbit coupling as well as the CPGE. The unpolarized assisted radiation, instead of the circularly polarized radiation, imposes an asymmetric distribution of the spin-polarized carriers in the system and results in a helicity dependent photocurrent.
Interplay between edge and bulk states in silicene nanoribbon
Authors: An Xing-Tao , Zhang Yan-Yang , Liu Jian-Jun , Li Shu-Shen
Published: June 2013

We investigate the interplay between the edge and bulk states, induced by the Rashba spin-orbit coupling, in a zigzag silicene nanoribbon in the presence of an external electric field. The interplay can be divided into two kinds, one is the interplay between the edge and bulk states with opposite velocities, and the other is that with the same velocity direction. The former can open small direct spin-dependent subgaps. A spin-polarized current can be generated in the nanoribbon as the Fermi energy is in the subgaps. While the later can give rise to the spin precession in the nanoribbon. Therefore, the zigzag silicene nanoribbon can be used as an efficient spin filter and spin modulation device.
Large-area microfocal spectroscopic ellipsometry mapping of thickness and electronic properties of epitaxial graphene on Si- and C-face of 3C-SiC(111)
Authors: Darakchieva V. , Boosalis A. , Zakharov A. A. , Hofmann T. , Schubert M. , Tiwald T. E. , Iakimov T. , Vasiliauskas R. , Yakimova R.
Published: June 2013

Microfocal spectroscopic ellipsometry mapping of the electronic properties and thickness of epitaxial graphene grown by high-temperature sublimation on 3C-SiC (111) substrates is reported. Growth of one monolayer graphene is demonstrated on both Si- and C-polarity of the 3C-SiC substrates and it is shown that large area homogeneous single monolayer graphene can be achieved on the Si-face substrates. Correlations between the number of graphene monolayers on one hand and the main transition associated with an exciton enhanced van Hove singularity at ∼4.5 eV and the free-charge carrier scattering time, on the other are established. It is shown that the interface structure on the Si- and C-polarity of the 3C-SiC(111) differs and has a determining role for the thickness and electronic properties homogeneity of the epitaxial graphene.
The effect of Ga-doped nanocrystalline ZnO electrode on deep-ultraviolet enhanced GaN photodetector
Authors: Wang R. X. , Yang L. C. , Zhang Y. M. , Xu S. J. , Fu K. , Zhang B. S. , Wang J. F. , Xu K. , Yang H.
Published: June 2013

Two types of GaN-based ultraviolet (UV) photodetectors were fabricated by using NiAu and Ga-doped ZnO (GZO) as electrode materials, respectively. Dark current-voltage and photoresponse characteristics of the devices were investigated. It is found that in addition to the ∼365 nm cut-off response of GaN, an enhanced responsivity at around 250 nm is achieved for the GZO/GaN photodetectors. Photo absorption measurements provide proof that the efficient deep UV absorption occurs in the solar blind spectral zone. Transmission electron microscopy observations reveal the existence of nanostructures in the GZO thin film. Such nanostructures could be responsible for the deep UV photoresponse.
Very low specific contact resistance measurements made on a highly p-type doped 4H-SiC layer selectively grown by vapor-liquid-solid transport
Authors: Thierry-Jebali N. , Vo-Ha A. , Carole D. , Lazar M. , Ferro G. , Planson D. , Henry A. , Brosselard P.
Published: June 2013

This work reports on the performances of ohmic contacts fabricated on highly p-type doped 4H-SiC epitaxial layer selectively grown by vapor-liquid-solid transport. Due to the very high doping level obtained, the contacts have an ohmic behavior even without any annealing process. Upon variation of annealing temperatures, it was shown that both 500 and 800 °C annealing temperature lead to a minimum value of the Specific Contact Resistance (SCR) down to 1.3×10−6 Ω⋅cm2. However, a large variation of the minimum SCR values has been observed (up to 4×10−4 Ω⋅cm2). Possible sources of this fluctuation have been also discussed in this paper.
New technique makes brains transparent
Authors: Miller Johanna L.
Published: June 2013

The ability to image single neurons deep beneath the organ’s surface facilitates three-dimensional mapping.
New center aims to move electric vehicles that extra mile
Authors: Matthews Jermey N. A.
Published: June 2013

US scientists and policymakers say breakthroughs in transportation-battery research are needed to curb greenhouse gas emissions and foreign oil imports.
Direct electrolytic dissolution of silicate minerals for air CO
2
mitigation and carbon-negative H
2
production
Authors: Rau Greg H. , Carroll Susan A. , Bourcier William L. , Singleton Michael J. , Smith Megan M. , Aines Roger D.
Published: June 2013

We experimentally demonstrate the direct coupling of silicate mineral dissolution with saline water electrolysis and H
2
production to effect significant air CO
2
absorption, chemical conversion, and storage in solution. In particular, we observed as much as a 10
5
-fold increase in OH
−
concentration (pH increase of up to 5.3 units) relative to experimental controls following the electrolysis of 0.25 M Na
2
SO
4
solutions when the anode was encased in powdered silicate mineral, either wollastonite or an ultramafic mineral. After electrolysis, full equilibration of the alkalized solution with air led to a significant pH reduction and as much as a 45-fold increase in dissolved inorganic carbon concentration. This demonstrated significant spontaneous air CO
2
capture, chemical conversion, and storage as a bicarbonate, predominantly as NaHCO
3
. The excess OH
−
initially formed in these experiments apparently resulted via neutralization of the anolyte acid, H
2
SO
4
, by reaction with the base mineral silicate at the anode, producing mineral sulfate and silica. This allowed the NaOH, normally generated at the cathode, to go unneutralized and to accumulate in the bulk electrolyte, ultimately reacting with atmospheric CO
2
to form dissolved bicarbonate. Using nongrid or nonpeak renewable electricity, optimized systems at large scale might allow relatively high-capacity, energy-efficient (<300 kJ/mol of CO
2
captured), and inexpensive (<$100 per tonne of CO
2
mitigated) removal of excess air CO
2
with production of carbon-negative H
2
. Furthermore, when added to the ocean, the produced hydroxide and/or (bi)carbonate could be useful in reducing sea-to-air CO
2
emissions and in neutralizing or offsetting the effects of ongoing ocean acidification.
Summer Habitat Use by Lake Sturgeon in Manistee Lake, Michigan
Authors: Damstra Richard A. , Galarowicz Tracy L.
Published: June 2013

The Lake Sturgeon Acipenser fulvescens is targeted for rehabilitation across its range, but little is known about habitat use by Lake Sturgeon during periods other than the spawning period. Insight into habitat use during nonspawning periods for these long‐lived fish is crucial to our understanding of this species and its recovery. Our goal was to characterize summer habitat use by Lake Sturgeon in Manistee Lake, Michigan, a drowned river mouth complex. Fish were tagged and relocated in the lake by using telemetry in 2003–2005. The lake was divided into 18 sampling sections, and abiotic and biotic variables with potential influences on habitat use were quantified in each section during May–July in 2003 and 2004. Lake Sturgeon were found in the lake during May–July and primarily occupied habitats near the wetland complex and shipping channel in the northern portion of the lake. Water depth, temperature, dissolved oxygen level, Secchi depth, and densities of chironomid larvae, dreissenid mussels, burrowing mayflies Hexagenia spp., and amphipods differed among sampling sections. Similarities between Lake Sturgeon relocation sites and the sampling sections were analyzed with Penrose distance statistics. Abiotic and biotic variables in the southern and central portions of the lake were most similar to those at sampling sections where Lake Sturgeon were relocated. The difference between southern and central sampling sections and the sections where fish were relocated suggests that habitat use was influenced by additional factors that were not monitored. Future efforts to conserve Lake Sturgeon populations should include habitat management during nonspawning periods.
Using a Stream Network Census of Fish and Habitat to Assess Models of Juvenile Salmonid Distribution
Authors: McMillan John R. , Liermann Martin C. , Starr James , Pess George R. , Augerot Xan
Published: June 2013

We censused juvenile salmonids and stream habitat over two consecutive summers to test the ability of habitat models to explain the distribution of juvenile Coho Salmon Oncorhynchus kisutch, young‐of‐the‐year (age‐0) steelhead O. mykiss, and steelhead parr (age ≥1) within a network consisting of several different‐sized streams. Our network‐scale habitat models explained 27, 11, and 19% of the variation in density of juvenile Coho Salmon, age‐0 steelhead, and steelhead parr, respectively, but strong levels of spatial autocorrelation were typically present in the residuals. Explanatory power of base habitat models increased and spatial autocorrelation decreased with the sequential inclusion of variables accounting for the effects of stream size, year, stream, reach location, and a tertiary interaction term. Stream‐scale models were highly variable. Fish–habitat associations were rarely linear and ranged from negative to positive; the variable accounting for location of the habitat within a stream was often more important than the habitat variables. The limited success of our network‐scale models was apparently related to variation in the strength and shape of fish–habitat associations across and within streams and years. These results indicate that there are several potential limitations to extrapolating models to broader areas based only on spatially limited surveys.
Negative Pressure Ventilation and Positive Pressure Ventilation Promote Comparable Levels of Ventilator-induced Diaphragmatic Dysfunction in Rats
Authors: Bruells Christian S. , Smuder Ashley J. , Reiss Lucy K. , Hudson Matthew B. , Nelson William Bradley , Wiggs Michael P. , Sollanek Kurt J. , Rossaint Rolf , Uhlig Stefan , Powers Scott K.
Published: June 2013

Background:

Mechanical ventilation is a life-saving intervention for patients with respiratory failure. Unfortunately, a major complication associated with prolonged mechanical ventilation is ventilator-induced diaphragmatic atrophy and contractile dysfunction, termed ventilator-induced diaphragmatic dysfunction (VIDD). Emerging evidence suggests that positive pressure ventilation (PPV) promotes lung damage (ventilator-induced lung injury [VILI]), resulting in the release of signaling molecules that foster atrophic signaling in the diaphragm and the resultant VIDD. Although a recent report suggests that negative pressure ventilation (NPV) results in less VILI than PPV, it is unknown whether NPV can protect against VIDD. Therefore, the authors tested the hypothesis that compared with PPV, NPV will result in a lower level of VIDD.

Methods:

Adult rats were randomly assigned to one of three experimental groups (n = 8 each): (1) acutely anesthetized control (CON), (2) 12 h of PPV, and (3) 12 h of NPV. Dependent measures included indices of VILI, diaphragmatic muscle fiber cross-sectional area, diaphragm contractile properties, and the activity of key proteases in the diaphragm.

Results:

Our results reveal that no differences existed in the degree of VILI between PPV and NPV animals as evidenced by VILI histological scores (CON = 0.082 ± 0.001; PPV = 0.22 ± 0.04; NPV = 0.25 ± 0.02; mean ± SEM). Both PPV and NPV resulted in VIDD. Importantly, no differences existed between PPV and NPV animals in diaphragmatic fiber cross-sectional area, contractile properties, and the activation of proteases.

Conclusion:

These results demonstrate that NPV and PPV result in similar levels of VILI and that NPV and PPV promote comparable levels of VIDD in rats.
Anoxybacillus

vitaminiphilus sp. nov., a strictly aerobic and moderately thermophilic bacterium isolated from a hot spring
Authors: Zhang Xin-Qi , Zhang Zhen-Li , Wu Nan , Zhu Xu-Fen , Wu Min
Published: June 2013

A strictly aerobic, Gram-stain-positive, motile and spore-forming bacterium, strain 3nP4T, was isolated from the Puge hot spring located in the south-western geothermal area of China. Strain 3nP4T grew at 38–66 °C (optimum 57–60 °C), at pH 6.0–9.3 (optimum 7.0–7.5) and with 0–4 % (w/v) NaCl (optimum 0–0.5 %). Phylogenetic analysis of 16S rRNA gene sequences, as well as DNA–DNA relatedness values, indicated that the isolate represents a novel species of the genus

Anoxybacillus

, related most closely to

Anoxybacillus voinovskiensis

DSM 12111T. Strain 3nP4T had diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and one unidentified phospholipid as major polar lipids and iso-C15 : 0 and iso-C17 : 0 as major fatty acids, which are both typical chemotaxonomic characteristics of the genus

Anoxybacillus

. The mean DNA G+C content of strain 3nP4T was 39.2±0.95 mol% (HPLC). A distinctive characteristic of the novel isolate was its extreme reliance on vitamin mixture or yeast extract for growth. Based on data from this taxonomic study using a polyphasic approach, strain 3nP4T is considered to represent a novel species of the genus

Anoxybacillus

, for which the name

Anoxybacillus

vitaminiphilus sp. nov. is proposed. The type strain is 3nP4T ( = CGMCC 1.8979T = JCM 16594T).
Hazenella coriacea gen. nov., sp. nov., isolated from clinical specimens
Authors: Buss Sarah N. , Cole Jocelyn A. , Hannett George E. , Nazarian Elizabeth J. , Nazarian Leah , Coorevits An , Van Landschoot Anita , De Vos Paul , Schumann Peter , Musser Kimberlee A. , Wolfgang William J.
Published: June 2013

A Gram-staining-positive, endospore-forming rod was isolated independently from clinical specimens in New York State, USA, once in 2009 and twice in 2011. The three isolates had identical 16S rRNA gene sequences and, based on their 16S rRNA gene sequence, are most closely related to the type strains of

Laceyella sediminis

and

L. sacchari

(94.6 % similarity). The partial 23S rRNA gene sequences of the three strains were also 100 % identical. Maximum-likelihood phylogenetic analysis suggests that the new isolates belong to the family

Thermoactinomycetaceae

. Additional biochemical and phenotypic characteristics of the strains support the family designation and suggest that the three isolates represent a single species. In each of the strains, the predominant menaquinone is MK-7, the diagnostic diamino acid is meso-diaminopimelic acid and the major cellular fatty acids are iso-C15 : 0, anteiso-C15 : 0 and iso-C13 : 0. The polar lipids are phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, four unknown phospholipids, four unknown aminophospholipids and an unknown lipid. It is proposed that the novel isolates represent a single novel species within a new genus, for which the name Hazenella coriacea gen. nov., sp. nov. is proposed. The type strain of Hazenella coriacea is strain 23436T ( = DSM 45707T = LMG 27204T).
UK Research Reserve: a sustainable model from print to E?
Authors: Yang Daryl
Published: May 2013

Purpose

This paper aims to provide a case study of the development of UK Research Reserve (UKRR): a partnership between the UK higher education sector and the British Library. The first of its kind in the UK as well as internationally, UK Research Reserve has helped its members de‐duplicate low‐use journals and release shelf space, as well as retain access to research material. UKRR is currently under review to determine a sustainable model if public funding becomes unavailable. This paper describes the journey UKRR has taken so far.

Design/methodology/approach

Research methods adopted can be categorised into two main groups of activities: information gathering (desk research, survey and interviews); and information analysis and synthesis (literature, data, documentation).

Findings

Through the case study of UKRR, the author identifies challenges and issues faced by research libraries, as well as the whole HE sector. This paper presents values and synergies UKRR has created for its members and beyond. It also shares UKRR's journey in identifying a sustainable business model beyond its current phase.

Originality/value

The author reviewed some second‐hand data to present a broader picture of challenges the HE sector is facing. Most data and documentation that support the other sections of the paper are first‐hand, and have been generated by UKRR's team.
Evaluation of the Effectiveness of Sugammadex for Verapamil Intoxication
Authors: Ozbilgin Sule , Ozbilgin Mucahit , Kucukoztas Beyza , Kamaci Gonca , Unek Tarkan , Yurtlu Bülent Serhan , Ensari Güneli Mehmet , Hanci Volkan , Gunerli Ali
Published: June 2013

Previous studies have shown that medications from the cyclodextrin family bind to verapamil. The aim of our study was to determine whether sugammadex could bind to verapamil and prevent the cardiovascular toxicity of that drug. Twenty‐eight sedated Wistar rats were infused with verapamil at 37.5 mg/kg/h. Five minutes after the start of infusion, the animals were treated with a bolus of either 16 mg/kg, 100 mg/kg or 1000 mg/kg sugammadex. The control group was treated with an infusion without sugammadex. The heart rate and respiratory rate were monitored, and an electrocardiogram was recorded. The primary end‐point was the time to asystole. The verapamil infusion continued until the animals arrested. The asystole time for the S16 group was significantly longer compared to those for the control and S1000 groups (p < 0.05). The asystole time for the S1000 group was significantly shorter than those for all of the other groups (p < 0.05). Reflecting these data, there was a near doubling of the mean lethal dose of verapamil from 13.57 mg/kg (S.D.±8.1) in the saline‐treated rats to 22.42 mg/kg (S.D.±9.9) in the sugammadex 16 group (p < 0.05). However, for the sugammadex 1000 group, the mean lethal dose was found to be 6.28 ± 1.11 mg/kg. This dose is significantly lower than those for all of the other groups (p < 0.05). We found that treatment with 16 mg/kg sugammadex delayed verapamil cardiotoxicity in rats. However, 1000 mg/kg sugammadex accelerated verapamil cardiotoxicity in rats. Further studies must be conducted to investigate the interaction between verapamil and sugammadex.
Alterations of N‐3 Polyunsaturated Fatty Acid‐Activated K2P Channels in Hypoxia‐Induced Pulmonary Hypertension
Authors: Nielsen Gorm , Wandall‐Frostholm Christine , Sadda Veeranjaneyulu , Oliván‐Viguera Aida , Lloyd Eric E. , Bryan Robert M. , Simonsen Ulf , Köhler Ralf
Published: June 2013

Polyunsaturated fatty acid (PUFA)‐activated two‐pore domain potassium channels (K2P) have been proposed to be expressed in the pulmonary vasculature. However, their physiological or pathophysiological roles are poorly defined. Here, we tested the hypothesis that PUFA‐activated K2P are involved in pulmonary vasorelaxation and that alterations of channel expression are pathophysiologically linked to pulmonary hypertension. Expression of PUFA‐activated K2P in the murine lung was investigated by quantitative reverse‐transcription polymerase chain reaction (qRT‐PCR), immunohistochemistry (IHC), by patch clamp (PC) and myography. K2P‐gene expression was examined in chronic hypoxic mice. qRT‐PCR showed that the K2P2.1 and K2P6.1 were the predominantly expressed K2P in the murine lung. IHC revealed protein expression of K2P2.1 and K2P6.1 in the endothelium of pulmonary arteries and of K2P6.1 in bronchial epithelium. PC showed pimozide‐sensitive K2P‐like K+‐current activated by docosahexaenoic acid (DHA) in freshly isolated endothelial cells as well as DHA‐induced membrane hyperpolarization. Myography on pulmonary arteries showed that DHA induced concentration‐dependent instantaneous relaxations that were resistant to endothelial removal and inhibition of NO and prostacyclin synthesis and to a cocktail of blockers of calcium‐activated K+ channels but were abolished by high extracellular (30 mM) K+‐concentration. Gene expression and protein of K2P2.1 were not altered in chronic hypoxic mice, while K2P6.1 was up‐regulated by fourfold. In conclusion, the PUFA‐activated K2P2.1 and K2P6.1 are expressed in murine lung and functional K2P‐like channels contribute to endothelium hyperpolarization and pulmonary artery relaxation. The increased K2P6.1‐gene expression may represent a novel counter‐regulatory mechanism in pulmonary hypertension and suggest that arterial K2P2.1 and K2P6.1 could be novel therapeutic targets.
A Revisit to Sample Size and Power Calculations for Testing Odds Ratio in Two Independent Binomials
Authors: Liu Fang
Published: June 2013

We reexamine the subject of sample size determination (SSD) when testing logarithm of odds ratio (OR) against zero in two independent binomials. Four common approaches are considered: a closed‐form SS formula based on the Wald test (), closed‐form formulas that meet SS requirement by score and exact tests respectively ( and ), and a numerical approach to calculating SS based on likelihood ratio (LR) tests (). Several practically useful findings are presented. First, is a strictly convex function of OR for OR and OR , respectively, implying that SS calculated by does not necessarily decrease as OR gets further away from 1. However, minimum SS often occurs at OR values that are deemed relatively extreme and rare in real life. , and decrease monotonically as OR diverges from 1. Secondly, the optimal sampling ratio (OSR) between two independent binomials that yields maximum power for a given total SS is not always 1:1 but depends on the odds of outcome in each arm. benefits the most from the application of OSR in that total SS can be significantly reduced as compared to the commonly used 1:1 sampling ratio. Savings in SS by OSR in , and are relatively immaterial from a practical perspective. Finally, we use simulation studies to examine the power loyalty of each SS approach and explore penalized likelihood as a remedy for undermined power loyalty.
Bridging Conditional and Marginal Inference for Spatially Referenced Binary Data
Authors: Boehm Laura , Reich Brian J. , Bandyopadhyay Dipankar
Published: June 2013

Spatially referenced binary data are common in epidemiology and public health. Owing to its elegant log‐odds interpretation of the regression coefficients, a natural model for these data is logistic regression. To account for missing confounding variables that might exhibit a spatial pattern (say, socioeconomic, biological, or environmental conditions), it is customary to include a Gaussian spatial random effect. Conditioned on the spatial random effect, the coefficients may be interpreted as log odds ratios. However, marginally over the random effects, the coefficients no longer preserve the log‐odds interpretation, and the estimates are hard to interpret and generalize to other spatial regions. To resolve this issue, we propose a new spatial random effect distribution through a copula framework which ensures that the regression coefficients maintain the log‐odds interpretation both conditional on and marginally over the spatial random effects. We present simulations to assess the robustness of our approach to various random effects, and apply it to an interesting dataset assessing periodontal health of Gullah‐speaking African Americans. The proposed methodology is flexible enough to handle areal or geo‐statistical datasets, and hierarchical models with multiple random intercepts.
National and ethnic identification, intergroup attitudes, and sport participation in the context of the London Olympics
Authors: Lam Virginia L. , Corson Eliza‐Jane
Published: June 2013

In the run‐up to the 2012 London Olympics, the sense of national identity was salient. We tested children (N = 401) aged 5–15 years living near the Olympic site on national (British) and ethnic identification, national ingroup and outgroup attitudes, and sport participation. It was found that the strength of British identification peaked at age 9 years, but the strength of ethnic identification remained stable with age. Both liking for, and stereotyping of, different national groups diverged from age 9 years, but whilst stereotyping remained diverged liking converged by 15 years. The ingroup was one of the most liked, but one of the least positively stereotyped groups. Sport participation declined with age and was higher among boys, whilst the lowest socio‐economic group showed the greatest discrepancy between normal and recent reported participation. The strength of British identification was associated with liking for, and stereotyping of, the British as well as sport participation, but the degree of associations varied between different groups of children.
The Final Frontiers of Healthcare Universalisation in Costa Rica and Panama
Authors: CLARK MARY A.
Published: June 2013

This article explains how Costa Rica and Panama, two Central American countries with nearly universal public healthcare programmes, have come to enjoy such broad coverage. It then describes the distinct paths each is taking towards reaching the populations still left out of healthcare coverage. Costa Rica is seeking to bring all residents under the umbrella of its ILO‐style social security plan. Panama is targeting the rural poor with a package of defined interventions aimed at maternal and child mortality. The article frames these cases within the literature on the varieties of universalism.
Contrasting responses of heterotrophic and autotrophic respiration to experimental warming in a winter annual‐dominated prairie
Authors: Li Dejun , Zhou Xuhui , Wu Liyou , Zhou Jizhong , Luo Yiqi
Published: June 2013

Understanding how soil respiration (Rs) and its source components respond to climate warming is crucial to improve model prediction of climate‐carbon (C) feedback. We conducted a manipulation experiment by warming and clipping in a prairie dominated by invasive winter annual Bromus japonicas in Southern Great Plains, USA. Infrared radiators were used to simulate climate warming by 3 °C and clipping was used to mimic yearly hay mowing. Heterotrophic respiration (Rh) was measured inside deep collars (70 cm deep) that excluded root growth, while total soil respiration (Rs) was measured inside surface collars (2–3 cm deep). Autotrophic respiration (Ra) was calculated by subtracting Rh from Rs. During 3 years of experiment from January 2010 to December 2012, warming had no significant effect on Rs. The neutral response of Rs to warming was due to compensatory effects of warming on Rh and Ra. Warming significantly (P < 0.05) stimulated Rh but decreased Ra. Clipping only marginally (P < 0.1) increased Ra in 2010 but had no effect on Rh. There were no significant interactive effects of warming and clipping on Rs or its components. Warming stimulated annual Rh by 22.0%, but decreased annual Ra by 29.0% across the 3 years. The decreased Ra was primarily associated with the warming‐induced decline of the winter annual productivity. Across the 3 years, warming increased Rh/Rs by 29.1% but clipping did not affect Rh/Rs. Our study highlights that climate warming may have contrasting effects on Rh and Ra in association with responses of plant productivity to warming.
Transparent Nano Crystalline Glass‐Ceramics by Interface Controlled Crystallization
Authors: Bocker Christian , Rüssel Christian , Avramov Isak
Published: June 2013

A prerequisite for the preparation of nano glass‐ceramics is an increase in viscosity of the residual glassy matrix phase during the course of the crystallization process. This results in a deceleration of the crystal growth process due to increasing stresses, which finally may lead to a total freezing of the crystallization process. In principle, two routes for the preparation of nano glass‐ceramics exist: in one of these routes, the first step is a phase separation in which a droplet phase is formed. Inside this droplet phase, the crystals are precipitated. In the other route, a preceding phase separation does not occur and the nucleation takes place in a homogeneous glassy phase. In both cases, the crystal growth velocity is high until the crystals reach a size of some nanometers or some ten nanometers, then the crystal growth velocity decreases strongly.
Influence of Aggregates in α‐Al2O3 Slurry on Orientation Degree of Powder Compact Fabricated by Magnetic Forming Method
Authors: Furushima Ryoichi , Kato Zenji , Uematsu Keizo , Tanaka Satoshi
Published: June 2013

The crystallographic orientation of α‐Al2O3 powder compact under a magnetic field is affected by the presence of aggregates. In this work, the influence of aggregates on the orientation degree was studied from the experimental and theoretical viewpoints. The optical parameter of birefringence was used as an evaluation index for the crystallographic orientation of α‐Al2O3 compact samples. The effect of aggregates on the orientation degree was estimated from the simulation of the distribution of the relative angles between the crystal axes of primary particles for any constituting number of aggregates. The orientation of an aggregate depends on the apparent crystal axes calculated from the vector summation of the crystal axes for all constituting particles. The measured degree of orientation of the powder compact was consistent with the theoretical values for all powder compact samples containing various concentrations and constituting numbers of aggregates. The elimination of aggregates is the key for good particle alignment under a magnetic field.
In Situ X‐ray Diffraction of Biased Ferroelastic Switching in Tetragonal Lead‐free (1−x)Ba(Zr0.2Ti0.8)O3–x(Ba0.7Ca0.3)TiO3 Piezoelectrics
Authors: Ehmke Matthias C. , Glaum Julia , Hoffman Mark , Blendell John E. , Bowman Keith J.
Published: June 2013

The effect of electric poling on the bipolar switching for tetragonal BZT–BCT materials is studied using large signal polarization and strain, small signal permittivity, and piezoelectric coefficient, as well as electric field–dependent in situ XRD experiments. Charge carrier agglomeration at domain and grain boundaries with increasing poling fields gives rise to an internal bias field that gradually biases domain switching behavior. The biased switching after electric poling is quantified during a bipolar measurement cycle from analysis of the electric and structural data. For a fresh sample the ferroelastic domain texture induced by a positive and negative electric measurement field is of the same magnitude. After poling, the induced ferroelastic domain texture is larger under a positive measurement field and smaller under a negative measurement field. A very large domain texture is achieved during poling, corresponding to 85% of the domains becoming aligned with their 002 pole in field direction. While the domain texture is significantly improved at higher poling fields, relaxation upon removal of the electric field appears independent of the poling history. This suggests a large extrinsic contribution to the macroscopic strain. It also facilitates the biased ferroelastic switching arising from the internal bias field developed during poling.
Thermal, Structural, and Enhanced Photoluminescence Properties of Eu3+‐doped Transparent Willemite Glass–Ceramic Nanocomposites
Authors: Tarafder Anal , Molla Atiar Rahaman , Dey Chirantan , Karmakar Basudeb
Published: June 2013

The precursor glass in the ZnO–Al2O3–B2O3–SiO2 (ZABS) system doped with Eu2O3 was prepared by the melt‐quench technique. The transparent willemite, Zn2SiO4 (ZS) glass–ceramic nanocomposites were derived from this precursor glass by a controlled crystallization process. The formation of willemite crystal phase, size, and morphology with increase in heat‐treatment time was examined by X‐ray diffraction (XRD) and field‐emission scanning electron microscopy (FESEM) techniques. The average calculated crystallite size obtained from XRD is found to be in the range 18–70 nm whereas the grain size observed in FESEM is 50–250 nm. The refractive index value is decreased with increase in heat‐treatment time which is caused by the partial replacement of ZnO4 units of ZS nanocrystals by AlO4 units due to generation of vacancies. Fourier transform infrared (FTIR) reflection spectroscopy was used to evaluate its structural evolution. Vickers hardness study indicates marked improvement of hardness in the resultant glass‐ceramics compared with its precursor glass. The photoluminescence spectra of Eu3+ ions exhibit emission transitions of 5D0→7Fj (j = 0, 1, 2, 3, and 4) and its excitation spectra show an intense absorption band at 395 nm. These spectra reveal that the luminescence performance of the glass–ceramic nanocomposites is enhanced up to 17‐fold with the process of heat treatment. This enhancement is caused by partitioning of Eu3+ ions into glassy phase instead of into the willemite crystals with progress of heat treatment. Such luminescent glass–ceramic nanocomposites are expected to find potential applications in solid‐state red lasers, phosphors, and optical display systems.
Benign dermoscopic features in melanoma
Authors: Di Stefani A. , Massone C. , Soyer H.P. , Zalaudek I. , Argenziano G. , Arzberger E. , Lozzi G.P. , Chimenti S. , Hofmann‐Wellenhof R.
Published: June 2013

Background

Various dermoscopic features are usually associated with benign melanocytic lesions. Our objective was to determine frequency and extension of benign dermoscopic features (BDF) in melanoma.

Methods

Retrospective review of dermoscopic images of a consecutive series of 516 histopathologically proven melanomas collected in 6 years in Graz. Correlation of BDF with mean Breslow thickness, with presence/absence of associated benign nevus component and with the pre‐operative clinico‐dermoscopic diagnosis, as reported on the original histopathologic reports.

Results

In addition to melanoma specific criteria, 42% of melanomas showed BDF. In 12.3% cases, the benign features occupied more than the half of the lesion. The BDF typical pigment network, homogeneous pattern and regular globules/cobblestone pattern had the highest frequency. BDF were associated with relatively thinner melanomas (mean Breslow thickness of 0.51 mm). The presence of BDF was observed in 67.1% of histopathologically documented nevus‐associated melanoma and in 35.7% of melanoma de novo. A pre‐operative clinico‐dermoscopic diagnosis of melanoma was achieved in only 54.1% of cases displaying BDF.

Conclusion

A significant proportion of melanomas may exhibit BDF. Clinicians should be aware of the presence of BDF in melanoma as possible diagnostic pitfall.
Microleakage of Teeth Restored with Different Adhesive Dowel Systems: An In Vitro Study
Authors: Sarı Tuğrul , Özyesil Atilla G.
Published: June 2013

Purpose

Commercial fiber‐reinforced dowel systems are marketed as having better adhesion and sealing ability than conventional metallic dowel systems. The aim of this in vitro study was to evaluate the microleakage of teeth restored with nine dowel systems.

Materials and Methods

Ninety mandibular second premolar teeth were decoronated, and nine homogenous groups were composed of ten teeth each. Root canal and dowel space preparations were made, and eight fiber‐reinforced composite dowel systems and one stainless steel dowel system were used to fabricate dowel restorations. Microleakage measurements of the restored teeth were made with a modified fluid filtration method, and data were collected. One sample Kolmogorov‐Smirnov, one‐way ANOVA, and Tukey‐HSD tests were performed on the relative microleakage data of the groups.

Results

Microleakage values were reported relative to those for teeth with unfilled canals. The highest and lowest relative microleakage values were recorded for the metallic Parapost (7.06 × 10−4%) and fiber‐reinforced Everstick (3.55 × 10−4%) groups, respectively. Significant differences in relative microleakage between the fiber‐reinforced dowels and stainless steel dowels were observed. Significant differences among the fiber‐reinforced dowel groups were observed as well.

Conclusions

The sealing ability of all fiber‐reinforced composite dowels is not better than that of stainless steel dowels, and there are significant differences among different fiber‐reinforced dowel systems as well. Differences among commercial dowel systems must be taken into consideration when making a selection.
An Electromyographic Analysis of Orbicularis Oris and Buccinator Muscle Activity in Patients with Complete Dentures Fabricated Using Two Neutral Zone Techniques—A Pilot Study
Authors: Ladha Komal G. , Gill Shubhra , Gupta Rekha , Verma Mahesh , Gupta Meena
Published: June 2013

Purpose

Several studies have evaluated electromyographic (EMG) activity of perioral muscles in patients using unsatisfactory old complete dentures and after the insertion of new clinically acceptable dentures; however, studies evaluating EMG activity of orbicularis oris (OO) and buccinator (BUC) muscles in patients wearing complete dentures fabricated using swallowing (SNZ) and phonetic neutral zone (PNZ) techniques are lacking in the literature. The purpose of this study was to evaluate differences in muscle activity of the superior orbicularis oris (SOO), inferior orbicularis oris (IOO) and BUC muscle during the use of unsatisfactory old complete dentures, in comparison with the satisfactory dentures fabricated using the two neutral zone techniques.

Materials and Methods

Ten completely edentulous participants dissatisfied with their existing mandibular complete dentures participated in the study. Each patient received two sets of new dentures fabricated using the SNZ and PNZ techniques. Surface EMG activity of the OO and BUC muscles was recorded using a 4‐channel Medelec premier plus electromyography machine while the patients still used their old dentures (group A) and with the SNZ (group B) and PNZ (group C) dentures. On the basis of participation in the study, five participants first received the SNZ dentures and five the PNZ type. After having worn the prosthesis for a minimum of 2 months, EMG recordings were repeated for the first set of dentures. The prostheses were then changed and the procedures repeated. The activity of OO and BUC muscles was recorded at rest, while pursing and laughing, and during pronunciation of various syllables. Results are expressed as mean ± SD and as absolute numbers and percentage. ANOVA with appropriate correction (Bonferroni or Tamhane) and Student's t‐test were used for statistical analysis. A p‐value < 0.05 was taken to indicate a significant difference.

Results

There was no statistically significant difference in the mean EMG activity of SOO, IOO, and BUC muscles at rest, or during pursing or laughing among the three groups. No significant difference was observed in the mean EMG activity of SOO and BUC muscle among the groups for all the syllables pronounced. For IOO, a statistically significant difference was observed among the groups for the words “baby” and “cheese.” Within‐group comparisons of the mean EMG activities of SOO and IOO during pronunciation and pursing showed no significant difference; however, at rest a statistically significant difference was observed in group B.

Conclusion

OO and BUC muscle activities did not significantly differ, irrespective of the technique used for fabrication of complete dentures.
A Simple Way to Intrude Overerupted Upper Second Molars with Miniscrews
Authors: Cao Yang , Liu Chufeng , Wang Chunxian , Yang Xiaoyu , Duan Peijia , Xu Chenrong
Published: June 2013

Various methods of using skeletal anchorage for the intrusion of overerupted maxillary molars have been reported; however, it is difficult to intrude the overerupted upper second molars because of the low bone density in the region of the tuberosity. This article illustrates a new treatment method using partial fixed edgewise appliances and miniscrews to intrude the overerupted upper second molars. The miniscrews were applied to reinforce the anchorage of the upper first molar. The intrusive force was generated by the Ni‐Ti wire. The clinical results showed a significant intrusion effect without root resorption or periodontal problems. This report demonstrates that the combination of partial conventional fixed appliances with miniscrews is a simple and effective treatment option to intrude overerupted upper second molars, especially in situations where miniscrews cannot be inserted directly next to the second molar.
Effect of Ultraviolet Aging on Translucency of Resin‐Cemented Ceramic Veneers: An In Vitro Study
Authors: Turgut Sedanur , Bagis Bora , Turkaslan Suha S. , Bagis Yildirim Hakan
Published: June 2013

Purpose

The aim of this in vitro study was to evaluate the translucency of ceramic veneers cemented with light‐ or dual‐cured resin cements after accelerated aging.

Materials and Methods

A total of 392 specimens were made of shade A1 with 0.5‐ and 1.0‐mm thickness. Light‐cured RelyX Veneer and dual‐cured Maxcem Elite and Variolink II resin cements were applied on the porcelain discs with a thickness of 0.1 mm. Translucency parameter (TP) values of the ceramic veneers after cementation and UV aging test were evaluated. Statistical analyses were done with ANOVA and Tukey's tests and paired sample t‐test (p < 0.05).

Results

All the resin cements affected the TP values of 0.5‐mm‐thick ceramic, while RelyX Veneer Tr (TP = 11.15; p = 0.608), Variolink II Tr (TP = 10.98; p = 0.55), and Maxcem Clear (TP = 11.81; p = 0.702) did not affect the translucency of 1‐mm‐thick ceramics (TP = 11.38). The aging process affected TP values of both ceramics and cemented ceramics, as the TP values decreased after aging. Among the TP values of opaque shade resin cements, there were significant differences between the “ceramic,” “ceramic + RelyX Veneer WO,” “ceramic + Variolink II WO,” and “ceramic + Maxcem WO” variables for both 0.5 and 1 mm thicknesses (p < 0.05). There were no significant differences between “ceramic,” “ceramic + RelyX Veneer Tr,” “ceramic + Variolink II Tr,” and “ceramic + Maxcem Clear” variables at 0.5 mm thickness, and there were no significant differences between “ceramic,” “ceramic + RelyX Veneer Tr,” and “ceramic + Variolink II Tr” variables after aging (p > 0.05).

Conclusions

The TP of the same color of resin cements varied related to the type or brand. Aging caused both the ceramics and cemented ceramics to become more opaque.