bluuebunny/crossref_metadata_2025 huggingface dataset:
Biotic and abiotic experimental identification of bacterial influence on calcium isotopic signatures
Authors: Cobert Florian , Schmitt Anne‐Désirée , Calvaruso Christophe , Turpault Marie‐Pierre , Lemarchand Damien , Collignon Christelle , Chabaux François , Stille Peter
Published: September 2011

In this study, we tested experimentally the influence of plant and bacterial activities on the calcium (Ca) isotope distribution between soil solutions and plant organs. Abiotic apatite weathering experiments were performed under two different pH conditions using mineral and organic acids. Biotic experiments were performed using either apatite or Ca‐enriched biotite substrates in the presence of Scots pines, inoculated or not with the rhizosphere bacterial strain Bulkholderia glathei PML1(12), or the B. glathei PML1(12) alone. For each experiment, the percolate was collected every week and analyzed for Ca concentrations and Ca isotopic ratios. No Ca isotopic fractionation was observed for the different abiotic experimental settings. This indicates that no Ca isotopic fractionation occurs during apatite dissolution, whatever the nature of the acid (mineral or organic). The main result of the biotic experiments is the 0.22 ‰ 44Ca enrichment recorded for a solution in contact with Scots pines grown on the bacteria‐free apatite substrate. In contrast, the presence of bacteria did not cause Ca isotopic fractionation of the solution collected after 14 weeks of the experiments. These preliminary results suggest that bacteria influence the Ca isotopic signatures by dissolving Ca from apatite more efficiently. Therefore, Ca isotopes might be suitable for detecting bacteria‐mediated processes in soils. Copyright © 2011 John Wiley & Sons, Ltd.
H ∞  sliding mode observer design for a class of nonlinear discrete time‐delay systems: A delay‐fractioning approach
Authors: Hu Jun , Wang Zidong , Niu Yugang , Stergioulas Lampros K.
Published: September 2011

In this paper, the H ∞  sliding mode observer (SMO) design problem is investigated for a class of nonlinear discrete time‐delay systems. The nonlinear descriptions quantify the maximum possible derivations from a linear model, and the system states are allowed to be immeasurable. Attention is focused on the design of a discrete‐time SMO such that the asymptotic stability as well as the H ∞  performance requirement of the error dynamics can be guaranteed in the presence of nonlinearities, time delay and external disturbances. Firstly, a discrete‐time discontinuous switched term is proposed to make sure that the reaching condition holds. Then, by constructing a new Lyapunov–Krasovskii functional based on the idea of ‘delay fractioning’ and by introducing some appropriate free‐weighting matrices, a sufficient condition is established to guarantee the desired performance of the error dynamics in the specified sliding mode surface by solving a minimization problem. Finally, an illustrative example is given to show the effectiveness of the designed SMO design scheme. Copyright © 2011 John Wiley & Sons, Ltd.
Giant components in Kronecker graphs
Authors: Horn Paul , Radcliffe Mary
Published: September 2011

Let
\documentclass{article} \usepackage{mathrsfs} \usepackage{amsmath, amssymb} \pagestyle{empty} \begin{document} \begin{align*}n\in\mathbb{N}\end{align*} \end{document}, 0 <α,β,γ< 1. Define the random Kronecker graph K(n,α,γ,β) to be the graph with vertex set
\documentclass{article} \usepackage{mathrsfs} \usepackage{amsmath, amssymb} \pagestyle{empty} \begin{document} \begin{align*}\mathbb{Z}_2^n\end{align*} \end{document}, where the probability that u is adjacent to v is given by pu,v =α u⋅vγ(1‐u)⋅(1‐v)βn‐u⋅v‐(1‐u)⋅(1‐v). This model has been shown to obey several useful properties of real‐world networks. We establish the asymptotic size of the giant component in the random Kronecker graph.© 2011 Wiley Periodicals, Inc. Random Struct. Alg.,2011
Laser gas assisted nitriding of Hastelloy G Alloy: thermal stress analysis and characterization
Authors: Yilbas B. S. , Akhtar S. S. , Karatas C.
Published: September 2011

Hastelloy G alloy has good high temperature strength and oxidation resistance. The hardness and tribological properties of the alloy surface can be improved through the laser nitriding process under a controlled environment. Laser gas assisted surface nitriding of Hastelloy G alloy is carried out using a CO2 laser. Temperature and stress fields in the nitrided layer are modeled using the finite element model. Metallurgical and morphological changes in the nitrided region are examined using SEM, energy dispersive spectroscopy, and X‐ray diffraction. It is found that a uniform nitride layer is formed in the surface region of the workpiece and the depth of the nitride layer extends over 40 µm below the surface. The nitride layer is free from cracks and surface abnormalities such as cavity and pores. Copyright © 2011 John Wiley & Sons, Ltd.
Towards a better understanding of software evolution: an empirical study on open‐source software
Authors: Neamtiu Iulian , Xie Guowu , Chen Jianbo
Published: September 2011

Software evolution is a fact of life. Over the past 30 years, researchers have proposed hypotheses on how software changes and provided evidence that both supports and refutes these hypotheses. To paint a clearer image of the software evolution process, we performed an empirical study on long spans in the lifetime of nine open‐source projects. Our analysis covers 705 official releases and a combined 108 years of evolution. We first tried to confirm Lehman's eight laws of software evolution on these projects using statistical hypothesis testing. Our findings indicate that only the laws of continuing change and continuing growth are confirmed for all programs, whereas the other six laws are violated by some programs, or can be both confirmed and invalidated, depending on the laws' operational definitions. Second, we analyze the growth rate for projects' development and maintenance branches, and the distribution of software changes. We find similarities in the evolution patterns of the programs we studied, which brings us closer to constructing rigorous models for software evolution. Copyright © 2011 John Wiley & Sons, Ltd.
A JAVA application framework for scientific software development
Authors: Fdez‐Riverola F. , Glez‐Peña D. , López‐Fernández H. , Reboiro‐Jato M. , Méndez J.R.
Published: September 2011

This paper presents AIBench (SING group, Ourense, Spain), a JAVA desktop application framework mainly focused on scientific software development, with the goal of improving the productivity of research groups. Following the MVC design pattern, the programmer is able to develop applications using only three types of concepts: operations, data‐typesand views. The framework provides the rest of the functionality present in typical scientific applications, including user parameter requests, logging facilities, multithreading execution, experiment repeatability and graphic user interface generation, among others. The proposed framework is implemented following a plugin‐based architecture, which also allows assembling new applications by the reuse of modules from past development projects. Copyright © 2011 John Wiley & Sons, Ltd.
Combination of acid‐demineralization and enzymatic desizing of cotton fabrics by using industrial acid stable glucoamylases and α‐amylases
Authors: Dehabadi Vahid Ameri , Opwis Klaus , Gutmann Jochen
Published: September 2011

In this study, the possibility of simultaneous acid‐demineralization and enzymatic desizing of cotton fabric in acidic conditions (pH 2) by using industrial acid stable enzymes has been investigated. Acid‐demineralization is necessary to remove undesired cationic metals and earth alkalis. Our experiments showed that by use of a mixture of two appropriate enzymes, a glucoamylase (Multifect GA 10L) and an α‐amylase (Optisize Next) in a solution of citric acid and presence of a chelating agent, enzymatic desizing, and acid‐demineralization can be successfully carried out at the same time. Therefore, two processes of pretreatment were integrated into a single process, which can effectively reduce time and costs for textile industry.
Gestational IV nicotine produces elevated brain‐derived neurotrophic factor in the mesocorticolimbic dopamine system of adolescent rat offspring
Authors: Harrod Steven B. , Lacy Ryan T. , Zhu Jun , Hughes Benjamin A. , Perna Marla K. , Brown Russell W.
Published: September 2011

Maternal smoking during pregnancy is associated with enduring psychopathology, such as increased likelihood of substance use, in offspring. Various animal models demonstrate that continuous nicotine exposure produces teratogenic effects in offspring, as well. In this experiment, a novel intravenous (IV) exposure model was used to determine if gestational nicotine (GN) treatment produced alterations in methamphetamine‐induced sensitization and the expression of brain‐derived neurotrophic factor (BDNF) in the mesocorticolimbic dopamine (DA) system of adolescent offspring. Dams were injected with IV saline or nicotine (0.05 mg/kg/injection) three times per day on gestational days 8–21. Habituation was measured on postnatal day (PND) 25–27 and baseline activity on PND 28. On PND 29–35, offspring were injected with saline or methamphetamine (0.3 mg/kg) and locomotor activity was measured after the first and seventh injections. On PND 36, brains were removed, flash frozen, and BDNF protein levels in the nucleus accumbens (NAcc), dorsal striatum (Str), frontal cortex (FC), and hippocampus (Hipp) were analyzed. GN did not affect habituation or the induction of methamphetamine‐induced sensitization. Interestingly, GN, but not adolescent methamphetamine treatment, elevated levels of BDNF in the NAcc and Str; however, the GN‐induced increase in BDNF in the FC was attenuated by adolescent methamphetamine treatment. Both GN and adolescent methamphetamine treatment increased BDNF in the Hipp. These findings indicate that GN exposure will result in increased levels of BDNF protein throughout the mesocorticolimbic DA system during adolescent development and suggests that methamphetamine abuse will modulate the expression of BDNF in motivational circuitries of adolescent offspring exposed to GN. Synapse, 2011. © 2011 Wiley‐Liss, Inc.
The antioxidant effects of pumpkin seed oil on subacute aflatoxin poisoning in mice
Authors: Eraslan Gökhan , Kanbur Murat , Aslan Öznur , Karabacak Mürsel
Published: September 2011

This study was aimed at the investigation of the antioxidant effect of pumpkin seed oil against the oxidative stress‐inducing potential of aflatoxin. For this purpose, 48 male BALB/c mice were used. Four groups, each comprising 12 mice, were established. Group 1 was maintained as the control group. Group 2 was administered with pumpkin seed oil alone at a dose of 1.5 mL/kg.bw/day (∼1375mg/kg.bw/day). Group 3 received aflatoxin (82.45% AFB1, 10.65% AFB2, 4.13% AFG1, and 2.77% AFG2) alone at a dose of 625 μg/kg.bw/day. Finally, group 4 was given both 1.5 mL/kg.bw/day pumpkin seed oil and 625 μg/kg.bw/day aflatoxin. All administrations were oral, performed with the aid of a gastric tube and continued for a period of 21 days. At the end of day 21, the liver, lungs, kidneys, brain, heart, and spleen of the animals were excised, and the extirpated tissues were homogenized appropriately. Malondialdehyde (MDA) levels and catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH‐Px) activities were determined in tissue homogenates. In conclusion, it was determined that aflatoxin exhibited adverse effects on most of the oxidative stress markers. The administration of pumpkin seed oil diminished aflatoxin‐induced adverse effects. In other words, the values of the group, which was administered with both aflatoxin and pumpkin seed oil, were observed to have drawn closer to the values of the control group. © 2011 Wiley Periodicals, Inc. Environ Toxicol 28: 681–688, 2013.
Advantages of the population‐based approach to pregnancy dating: results from 23 020 ultrasound examinations
Authors: Økland I. , Nakling J. , Gjessing H. K. , Grøttum P. , Eik‐Nes S. H.
Published: September 2011

Objective

To confirm the results from two previous evaluations of term prediction models, including two sample‐based models and one population‐based model, in a third population.

Methods

In a study population of 23 020 second‐trimester ultrasound examinations, data were prospectively collected and registered over the period 1988–2009. Three different models for ultrasonically estimated date of delivery were applied to the measurements of fetal biparietal diameter (BPD) and two models were applied to the femur length (FL) measurements; the resulting term estimations were compared with the actual time of delivery. The difference between the actual and the predicted dates of delivery (the median bias) was calculated for each of the models, for three BPD/FL‐measurement subgroups and for the study population as a whole.

Results

For the population‐based model, the median bias was + 0.4 days for the BPD‐based predictions and − 0.4 days for the FL‐based predictions, and the biases were stable over the inclusion ranges. The biases of the two traditional models varied with the size of the fetus at examination; median biases were − 0.87 and + 2.2 days, respectively, with extremes − 4.2 and + 4.8 days for the BPD‐based predictions, and the median bias was + 1.72 days with range − 0.8 to + 4.5 days for FL‐based predictions. The disagreement between the two sample‐based models was never less than 2 days for the BPD‐based predictions.

Conclusion

This study confirms the results from previous studies; median biases were negligible with term predictions from the population‐based model, while those from the traditional models varied substantially. The biases, which have clinical implications, seem inevitable with the sample‐based models, which, even if overall biases were removed, will perform unsatisfactorily. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Left ventricular midwall mechanics at 24 weeks' gestation in high‐risk normotensive pregnant women: relationship to placenta‐related complications of pregnancy
Authors: Novelli G. P. , Vasapollo B. , Gagliardi G. , Tiralongo G. M. , Pisani I. , Manfellotto D. , Giannini L. , Valensise H.
Published: September 2011

Objectives

Most studies during pregnancy have assessed maternal left ventricular (LV) function by load‐dependent indices, assessing only chamber function. The aim of this study was to assess afterload‐adjusted LV myocardial and chamber systolic function at 24 weeks' gestation and 6 months postpartum in high‐risk normotensive pregnant women.

Methods

A group of 118 high‐risk women with bilateral notching of the uterine arteries underwent an echocardiographic examination to evaluate midwall mechanics (midwall shortening (mFS%) and stress‐corrected midwall shortening (SCmFS%)) of the LV at 24 weeks' gestation and 6 months postpartum. Patients were followed until delivery and pregnancies were classified retrospectively as uneventful (uncomplicated outcome) or complicated. A control group of 54 low‐risk women with uneventful pregnancies without bilateral notching was also enrolled.

Results

The pregnancy was uneventful in 74 (62.7%) women, whereas 44 (37.3%) developed complications. At 24 weeks' gestation, mFS% and SCmFS% were greater in the uncomplicated‐outcome compared with the complicated‐outcome group (25.9 ± 4.8 vs 18.8 ± 5.0%, P < 0.001 and 107.9 ± 18.4 vs 77.9 ± 20.7%, P < 0.001, respectively). At 6 months postpartum, SCmFS% remained greater in the uncomplicated‐outcome compared with the complicated‐outcome group (100.4 ± 21.6 vs 87.8 ± 19.1, P < 0.05). In the uncomplicated‐outcome group, SCmFS% was higher during pregnancy than it was postpartum, whereas in the complicated‐outcome group, it was lower during pregnancy than it was postpartum (P < 0.05).

Conclusions

Maternal cardiac midwall mechanics appear to be enhanced (SCmFS% increased compared with controls) during pregnancy compared with postpartum in high‐risk patients with uncomplicated pregnancy, whereas midwall mechanics are depressed both during pregnancy and postpartum in patients with pregnancy complications. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Performance analysis of hybrid transmit antenna selection/maximal‐ratio transmission in Nakagami‐m fading channels
Authors: Coşkun Ahmet F. , Kucur Oğuz
Published: September 2011

Hybrid diversity systems have been of great importance because they provide better diversity orders and robustness to the fading effects of wireless communication systems. This paper focuses on the performance analysis of multiple‐input gle‐output systems that employ combined transmit antenna selection (TAS)/maximal‐ratio transmission (MRT) techniques (i.e., hybrid TAS/MRT). The probability density function, the moment generating function and the nth order moments of the output signal‐to‐noise ratio of the investigated diversity scheme are derived for independent identically distributed flat Nakagami‐m fading channels. The system capacity of the hybrid TAS/MRT scheme is examined from the outage probability perspective. Exact bit/symbol error rate (BER/SER) expressions for binary frequency shift keying, M‐ary phase shift keying and square M‐ary quadrature amplitude modulation signals are derived by using the moment generating function‐based analysis method. By deriving the upper bounds for BER/SER expressions, it is also shown that the investigated systems achieve full diversity orders at high signal‐to‐noise ratios. Also, by Monte Carlo simulations, analytical performance results are validated and the effect of feedback delay, channel estimation error and feedback quantization error on BER/SER performances are examined. Copyright © 2011 John Wiley & Sons, Ltd.
Aerodynamic optimization of wind turbine rotors using a blade element momentum method with corrections for wake rotation and expansion
Authors: Døssing Mads , Madsen Helge Aa. , Bak Christian
Published: September 2011

The blade element momentum (BEM) method is widely used for calculating the quasi‐steady aerodynamics of horizontal axis wind turbines. Recently, the BEM method has been expanded to include corrections for wake expansion and the pressure due to wake rotation (), and more accurate solutions can now be obtained in the blade root and tip sections. It is expected that this will lead to small changes in optimum blade designs. In this work, has been implemented, and the spanwise load distribution has been optimized to find the highest possible power production. For comparison, optimizations have been carried out using BEM as well. Validation of shows good agreement with the flow calculated using an advanced actuator disk method. The maximum power was found at a tip speed ratio of 7 using , and this is lower than the optimum tip speed ratio of 8 found for BEM. The difference is primarily caused by the positive effect of wake rotation, which locally causes the efficiency to exceed the Betz limit. Wake expansion has a negative effect, which is most important at high tip speed ratios. It was further found that by using , it is possible to obtain a 5% reduction in flap bending moment when compared with BEM. In short, allows fast aerodynamic calculations and optimizations with a much higher degree of accuracy than the traditional BEM model. Copyright © 2011 John Wiley & Sons, Ltd.
Analysis of wake measurements from the ECN Wind Turbine Test Site Wieringermeer, EWTW
Authors: Schepers J. G. , Obdam T. S. , Prospathopoulos J.
Published: September 2011

This paper describes an analysis of wake measurements from the research farm at the ECN Wind Turbine Test Site Wieringermeer. This research farm is owned and operated by the Energy Research Centre of the Netherlands. The farm consists of five research turbines that are oriented in a single line with a mutual distance of 3.8D(iameter). The turbines are variable speed and pitch controlled, and they have a diameter and a hub height of 80 m. The rated power of the turbines is 2.5 MW. Extensive machine measurements (power, loads, yaw angle and pitch angles) are carried out on these turbines. In parallel, meteorological measurements are done on a 108 m mast that is instrumented at three heights (hub height and hub height ± 70% span) with sonic anemometers and cups and wind vanes. This mast is located at a shortest distance of 2.5D from one of the turbines. Data have been collected over a period of almost 5 years, and they are used to study several phenomena mainly related to wake aerodynamics, e.g. power losses in the wake of up to four wind turbines and meteorological wake phenomena at different distances behind the turbines. Copyright © 2011 John Wiley & Sons, Ltd.
Can restoring wolves aid in lynx recovery?
Authors: Ripple William J. , Wirsing Aaron J. , Beschta Robert L. , Buskirk Steven W.
Published: September 2011

Herein, we examine the hypothesis that relatively low densities of snowshoe hares (Lepus americanus) and the imperiled status of lynx (Lynx canadensis) may be partially due to an ecological cascade caused by the extirpation of gray wolves (Canis lupus) in most of the conterminous United States decades ago. This hypothesis focuses on 2 plausible mechanisms, one involving “mesopredator release” of the coyote (C. latrans), which expanded its distribution and abundance continentally following the ecological extinction of wolves over the temperate portion of their geographic range. In the absence of wolves, coyotes may have affected lynx via increased predation on snowshoe hares, on which the lynx specializes, and/or by direct killing of lynx. The second mechanism involves increased browsing pressure by native and domestic ungulates following the declines in wolves. A recovery of long‐absent wolf populations could potentially set off a chain of events triggering a long‐term decrease in coyotes and ungulates, improved plant communities, and eventually an increase in hares and lynx. This prediction, and others that we make, are testable. Ecological implications for the lynx may be dependent upon whether wolves are allowed to achieve ecologically effective populations where they recolonize or are reintroduced in lynx habitat. We emphasize the importance of little‐considered trophic and competitive interactions when attempting to recover an endangered carnivore such as the lynx. © 2011 The Wildlife Society.
The rhetoric and reality of youth mentoring
Authors: Rhodes Jean E. , Grossman Jean B. , Roffman Jennifer
Published: September 2011

Enduring and supportive mentoring relationships can powerfully influence the course and quality of adolescent lives. As mentoring continues to expand, community agencies are implementing alternatives to the traditional one‐on‐one mentoring mode. Such efforts may help to reach youth who might otherwise fall through the cracks.
Enhanced cytokine‐induced mechanical hyperalgesia in skeletal muscle produced by a novel mechanism in rats exposed to unpredictable sound stress
Authors: Dinal Olayinka A. , Levinel Jon D. , Greenl Paul G.
Published: September 2011

Stress exacerbates both experimental and clinical pain, most well‐characterized in irritable bowel and fibromyalgia syndromes. Since it has been hypothesized that cytokines play an etiopathogenic role in fibromyalgia and other chronic widespread pain conditions, we investigated the relationship between stress and cytokines in a model of stress‐induced chronic somatic pain. A series of experiments were performed to evaluate the impact of stress on the hyperalgesia‐induced by endotoxin (lipopolysaccharide, LPS) and the role of two pro‐inflammatory cytokines, interleukin‐6 (IL‐6) and tumor necrosis α (TNFα). Fourteen days after exposure to a 4‐day protocol of unpredictable sound stress, the ability of systemic LPS (100μg/kg, i.p) to elicit cytokine‐mediated mechanical hyperalgesia was measured in gastrocnemius muscle. LPS‐induced hyperalgesia was significantly greater in stressed rats, but when rats were treated intrathecally with antisense oligodeoxynucleotide (ODN), to decrease either the gp130 subunit of the IL‐6 receptor or the TNFα receptor, in nociceptors, skeletal muscle hyperalgesia in sound stressed, but not control, rats was prevented. These data suggest that chronic stress alters signaling in the primary afferent nociceptor for the hyperalgesia induced by endogenously produced pro‐inflammatory cytokines.
Clinical Outcome following Pneumonectomy for Management of Chronic Pyothorax in Four Cats
Authors: Crawford Abbe H , Halfacree Zoe J , Lee Karla CL , Brockman Daniel J
Published: September 2011

Pneumonectomy is the resection of all lung lobes from one side of the thorax. The clinical findings, treatment and outcome of four cases of feline chronic pyothorax managed with exploratory thoracotomy and pneumonectomy are reported. All cases were initially medically managed with thoracic drain placement and antibiosis. However, resolution was not achieved with medical therapy and diagnostic imaging findings consistent with an area of abscessation or marked lung lobe consolidation were identified, supporting a decision for surgical management. Surgical exploration was performed via median sternotomy and, on the basis of gross inspection, non-functional lung was removed. A left-sided pneumonectomy was performed in three cats and a right-sided pneumonectomy in one. All cases survived to discharge and an excellent quality of life was reported on long-term follow-up. Pneumonectomy appears to be well tolerated in the cat.
Biliothorax in a Siamese Cat
Authors: Wustefeld-Janssens Brandan G , Loureiro Joao F , Dukes-McEwan Joanna , German Alexander J , Burrow Rachel D
Published: September 2011

A 2-year-old male neutered cat presented for further investigation of biliothorax. The cat was initially treated for pyothorax, including bilateral chest drains for lavage of the pleural space. Five days later, the pleural effusion turned clear-yellow and had a bilirubin concentration of 427 μmol/l compared to the serum bilirubin concentration of 15 μmol/l. Exploratory surgery revealed a 2 mm tear in the diaphragm, with a corresponding 2 mm defect in the diaphragmatic surface of the gall bladder, creating a fistula between the gall bladder and the pleural cavity. The defects were repaired routinely and the cat made a full recovery. It was suspected that the tears had been created at the time of the thoracostomy tube placement. Biliothorax has not been described before in a cat, and appears to be a rare complication following thoracostomy tube placement.
A record of late-Holocene environmental change from southern New England, USA
Authors: Oswald W. Wyatt , Foster David R.
Published: September 2011

Analyses of a sediment core from Little Pond, located in the town of Bolton, Massachusetts, provide new insights into the history of environmental and ecological changes in southern New England during the late Holocene. Declines in organic content and peaks in the abundance of Isoetes spores indicate reduced water depth at 2900–2600, 2200–1800, and 1200–800 calibrated years before present (cal yr BP), generally consistent with the timing of dry conditions in records from elsewhere in the northeastern United States. The Little Pond pollen record features little change over the last 3000 yr, indicating that the surrounding vegetation was relatively insensitive to these periods of drought. The 1200–800 cal yr BP dry interval, however, coincides with increased abundance of Castanea pollen, suggesting that the expansion of Castanea in southern New England may have been influenced by late-Holocene climatic variability.
An experimental study of boundary layer transition induced by a cylinder wake
Authors: Mandal A. C. , Dey J.
Published: September 2011

Boundary layer transition induced by the wake of a circular cylinder in the free stream has been investigated using the particle image velocimetry technique. Some differences between simulation and experimental studies have been reported in the literature, and these have motivated the present study. The appearance of spanwise vortices in the early stage is further confirmed here. A spanwise vortex appears to evolve into a$ \mrm{\Lambda} $/hairpin vortex; the flow statistics also confirm such vortices. With increasing Reynolds number, based on the cylinder diameter, and with decreasing cylinder height from the plate, the physical size of these hairpin-like structures is found to decrease. Some mean flow characteristics, including the streamwise growth of the disturbance energy, in a wake-induced transition resemble those in bypass transition induced by free stream turbulence. Streamwise velocity streaks that are eventually generated in the late stage often undergo sinuous-type oscillations. Similar to other transitional flows, an inclined shear layer in the wall-normal plane is often seen to oscillate and shed vortices. The normalized shedding frequency of these vortices, estimated from the spatial spacing and the convection velocity of these vortices, is found to be independent of the Reynolds number, similar to that in ribbon-induced transition. Although the nature of free stream disturbance in a wake-induced transition and that in a bypass transition are different, the late-stage features including the flow breakdown characteristics of these two transitions appear to be similar.
“Little Moscows” in Western Europe: The Ecology of Small-Place Communism
Authors: Knotter Ad
Published: September 2011

Small communist strongholds were commonly nicknamed “Little Moscow”, both in Britain and in Europe. Small-place communism has been widespread since the interwar period, often in distinctly hostile surroundings. In this article, based on research into a number of cases in western Europe, I try to identify common characteristics which might explain their receptiveness to communist policies and ideas. My aim is to present a taxonomy for further research. Most of the places that I researched were isolated, recently developed, and mono-industrial. They were populated by a wave of migrants who had formed mono-occupational, pioneer societies. Second-generation migrants turned to communism and built “occupational communities” based on trade unions and other associational activities. Often they continued militant traditions of earlier socialism, anarchism, or syndicalism; others had a tradition of irreligiousness or religious indifference.
Design and analysis of a totally decoupled 3-DOF spherical parallel manipulator – ERRATUM
Authors: Zhang Dan , Zhang Fan
Published: September 2011

The following corrections to the paper by Zhang et al.1 should be noted. The corrected paper follows this notice.

The title of the originally published paper should be corrected to “Design and analysis of a 3-DOF spherical parallel manipulator.”
CMC-based projects and L2 learning: confirming the importance of nativisation
Authors: Grosbois Muriel
Published: September 2011

Despite the spread of reliable desktop audio and videoconferencing facilities, some CMC-based projects still rely on asynchronous written environments, if only because of the temporal constraints of synchronicity (Guichon, 2009; Develotte, Guichon & Vincent, 2010). Yet speaking is usually the skill students most need to improve when learning a second language (L2). This paper therefore sets out to measure the impact of distant written exchanges between Native Speakers (NS) and Non Native Speakers (NNS) on the development of NNS L2 oral output, focusing specifically on the effect of phonological nativisation. The context of this study is a teacher training programme for future primary school teachers in France. During their L2 course aiming to help them improve their mastery of English, they were given the opportunity to take part in a CMC-based project with PGCE (Postgraduate Certificate in Education) students from King's College, London. Action research was thus carried out to examine the potential of this project in the development of the participants’ L2 oral output.

The L2 course being task-oriented, the trainee teachers’ L2 oral output was evaluated by means of pre- and post-tests based on tasks. The results show that stability prevails over progress, which is in keeping with the fact that interlanguage development is a long process (Chapelle, 2003: 119). The results also confirm the importance of phonological nativisation when learners have access only towrittenauthentic input.
COLLECTIVE ACTION AND CONTRACT RIGHTS
Authors: Hodgson Louis-Philippe
Published: September 2011

The possibility of collective action is essential to human freedom; yet, as Rousseau famously argued, individuals acting together allow themselves to depend on one another's choices and thereby jeopardize one another's freedom. These two facts jointly constitute what I call the normative problem of collective action. I argue that solving this problem is harder than it looks: it cannot be done merely in terms of moral obligations; indeed, it ultimately requires putting in place a full-fledged system of contract rights. The point has important ramifications for contract theory: the role that contract rights play in reconciling collective action and freedom turns out to be crucial to understanding how—and by whom—these rights can legitimately be enforced. It also explains why expectation damages should be the standard remedy for breach of contract.
Error-rate analysis of the OFDM for correlated Nakagami-m fading channel by using maximal-ratio combining diversity
Authors: Dwivedi Vivek K. , Singh Ghanshyam
Published: September 2011

In this paper, we have analyzed the performance of correlated Nakagami-m fading channel by using the maximal-ratio-combing diversity at the receiver. A closed-form mathematical expression is derived for the average bit error rate (BER) for binary phase-shift keying (BPSK) and average symbol-error-rate (SER) for M-Quardrature amplitude modulation (M-QAM) scheme in terms of the higher transcendental function such as Appell hypergeometric function by using the well-known moment generating function (MGF)-based approach with arbitrary fading index for the orthogonal frequency division multiplexing (OFDM) communication systems. Moreover, we also derived an expression for the outage probability and the proposed numerical results are compared with the reported literature.
New insights into reliability of electrostatic capacitive RF MEMS switches
Authors: Zaghloul Usama , Papaioannou George J. , Bhushan Bharat , Coccetti Fabio , Pons Patrick , Plana Robert
Published: September 2011

Among other reliability concerns, the dielectric charging is considered the major failure mechanism which hinders the commercialization of electrostatic capacitive radio frequency micro-electro-mechanical systems (RF MEMS) switches. In this study, Kelvin probe force microscopy (KPFM) surface potential measurements have been employed to study this phenomenon. Several novel KPFM-based characterization methods have been proposed to investigate the charging in bare dielectric films, metal–insulator–metal (MIM) capacitors, and MEMS switches, and the results from these methods have been correlated. The used dielectric material is plasma-enhanced chemical vapor deposition (PECVD) silicon nitride. The SiNxfilms have been charged by using a biased atomic force microscope (AFM) tip or by electrically stressing MIM capacitors and MEMS switches. The influence of several parameters on the dielectric charging has been studied: dielectric film thickness, deposition conditions, and under layers. Fourier transform infra-red (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS) material characterization techniques have been used to determine the chemical bonds and compositions, respectively, of the SiNxfilms. The data from the physical material characterization have been correlated to the KPFM results. The study provides an accurate understanding of the charging/discharging processes in dielectric films implemented in electrostatic MEMS devices.
The incredible shrinking organelle
Authors: Gray Michael W
Published: September 2011

The mitochondrion is probably the evolutionary remnant of a bacterial symbiont, yet contemporary mitochondria are nothing like contemporary bacteria. Evolutionary shrinkage of the mitochondrial genome is well documented, but what about wholesale shrinkage of the organelle itself?
LRPPRC mutation suppresses cytochrome oxidase activity by altering mitochondrial RNA transcript stability in a mouse model
Authors: Xu Fenghao , Addis Jane B. L. , Cameron Jessie M. , Robinson Brian H.
Published: September 2011

LRPPRC (leucine-rich pentatricopeptide repeat-containing) has been shown to be essential for the maturation of COX (cytochrome c oxidase), possibly by stabilizing RNA transcripts of COXI, COXII and COXIII genes encoded in mtDNA (mitochondrial DNA). We established a mouse ‘gene-trap’ model using ES cells (embryonic stem cells) in which the C-terminus of LRPPRC has been replaced with a β-geo construct. Mice homozygous for this modification were found to be subject to embryonic lethality, with death before 12.5 dpc (days post-coitum). Biochemical analysis of MEFs (mouse embryonic fibroblasts) isolated from homozygous mutants showed a major decrease in COX activity, with slight reductions in other respiratory chain complexes with mtDNA encoded components. Constructs of LRPPRC containing different numbers of PPRs (pentatricopeptide repeats) were expressed as recombinant proteins and tested for their ability to bind to the COXI mRNA transcript. Full binding required the first 19 PPR motifs. A specific segment of COXI mRNA was identified as the binding target for LRPPRC, encoded by mouse mtDNA nucleotides 5961–6020. These data strongly suggest that LRPPRC is involved in the maturation of COX, and is involved in stabilizing of mitochondrial mRNAs encoding COX transcripts.
Protein metabolism and gene expression in skeletal muscle of critically ill patients with sepsis
Authors: Klaude Maria , Mori Maiko , Tjäder Inga , Gustafsson Thomas , Wernerman Jan , Rooyackers Olav
Published: September 2011

Muscle wasting negatively affects morbidity and mortality in critically ill patients. This progressive wasting is accompanied by, in general, a normal muscle PS (protein synthesis) rate. In the present study, we investigated whether muscle protein degradation is increased in critically ill patients with sepsis and which proteolytic enzyme systems are involved in this degradation. Eight patients and seven healthy volunteers were studied. In vivo muscle protein kinetics was measured using arteriovenous balance techniques with stable isotope tracers. The activities of the major proteolytic enzyme systems were analysed in combination with mRNA expression of genes related to these proteolytic systems. Results show that critically ill patients with sepsis have a variable but normal muscle PS rate, whereas protein degradation rates are dramatically increased (up to 160%). Of the major proteolytic enzyme systems both the proteasome and the lysosomal systems had higher activities in the patients, whereas calpain and caspase activities were not changed. Gene expression of several genes related to the proteasome system was increased in the patients. mRNA levels of the two main lysosomal enzymes (cathepsin B and L) were not changed but, conversely, genes related to calpain and caspase had a higher expression in the muscles of the patients. In conclusion, the dramatic muscle wasting seen in critically ill patients with sepsis is due to increased protein degradation. This is facilitated by increased activities of both the proteasome and lysosomal proteolytic systems.
Guidelines for Teaching Speech-Language Pathologists About the AAC Assessment Process
Authors: Fishman Iris
Published: September 2011

Although students may not become augmentative and alternative communication (AAC) clinical specialists, they often will work with individuals demonstrating complex communication needs who benefit from AAC. This necessitates knowledge of some basic principles of assessment including AAC assessment as a team process involving planning and implementing interventions for current and future communication needs; the inclusion of no-tech, low-tech, and high-tech communication systems; and assessing communication needs with partners in the individual's social network. The assessment also must include a capability profile and feature matching to select the appropriate components of the AAC system. Because the system we provide for today will become the system we use tomorrow, assessment must be considered an ongoing process throughout the lifespan of the individual.
Absence of ferromagnetism in Mn-doped tetragonal zirconia
Authors: Srivastava S. K. , Lejay P. , Barbara B. , Boisron O. , Pailhès S. , Bouzerar G.
Published: September 2011

In a recent letter, it has been predicted within first principle studies that Mn-doped ZrO2 compounds could be good candidates for spintronics application because expected to exhibit ferromagnetism far beyond room temperature. Our purpose is to address this issue experimentally for Mn-doped tetragonal zirconia. We have prepared polycrystalline samples of Y0.15(Zr0.85−yMny)O2 (y = 0, 0.05, 0.10, 0.15, 0.20) by using standard solid state method at equilibrium. The obtained samples were carefully characterized by using x-ray diffraction, scanning electron microscopy, elemental color mapping, x-ray photoemission spectroscopy, and magnetization measurements. From the detailed structural analyses, we have observed that the 5% Mn doped compound crystallized into two symmetries (dominating tetragonal and monoclinic), whereas higher Mn doped compounds are found to be in the tetragonal symmetry only. The spectral splitting of the Mn 3s core-level x-ray photoelectron spectra confirms that Mn ions are in the Mn3+ oxidation state and indicate a local magnetic moment of about 4.5 μB/Mn. Magnetic measurements showed that compounds up to 10% of Mn doping are paramagnetic with antiferromagnetic interactions. However, higher Mn doped compound exhibits local ferrimagnetic ordering. Thus, no ferromagnetism has been observed for all Mn-doped tetragonal ZrO2 samples.
Generation-recombination noise in bipolar graphene
Authors: Sokolov V. N. , Kochelap V. A. , Kim K. W.
Published: September 2011

A theoretical model is developed for the intrinsic generation-recombination (G-R) noise in bipolar graphene that stems from stochastic processes of interband carrier transitions in the zero-gap single layer. The correlation functions are obtained for microscopic Langevin sources of fluctuations relevant to the considered G-R processes. The spectral density of the G-R fluctuations is of a Lorentz shape with the characteristic frequency fc=1/2πτr, where the recombination time τr is expressed through the G-R rates and the carrier density. Numerical estimates clearly demonstrate the potential dominance of G-R noise over the Nyquist and flicker noise in monolayer graphene.
Enhancement of irradiation-induced defect production in Si nanowires
Authors: Hoilijoki S. , Holmström E. , Nordlund K.
Published: September 2011

We performed classical molecular dynamics simulations of defect production in small-diameter hexagonal Si nanowires under Ar ion irradiation. Using irradiation energies of 30 eV to 10 keV, we find that for low energies the defect production in the nanowires may be enhanced by as much as a factor of 3 in comparison to bulk Si due to the large surface-to-volume ratio of the systems. Conversely, at higher energies the increased transmission of ions causes a significant decrease in defect production.
Superparamagnetic behavior in cobalt iron oxide nanotube arrays by atomic layer deposition
Authors: Chong Yuen Tung , Yau Man Yan Eric , Yang Yang , Zacharias Margit , Görlitz Detlef , Nielsch Kornelius , Bachmann Julien
Published: September 2011

Cobalt iron oxide nanotube arrays with various wall thicknesses were prepared by atomic layer deposition in porous anodic alumina template. Nanotubes uniform in thickness and homogeneous in composition can be obtained with aspect ratios on the order of 50. These nanotubes have a polycrystalline spinel structure. Both the mean grain size and the grain size distribution increase with the tube wall thickness. Correspondingly, their magnetic properties (remanence and coercive field) also have a strong dependence on the thickness for measurements carried out at 300 K. This dependence is attributed to the superparamagnetic behavior of the grains that constitute the nanotube.
Determining the high-pressure phase transition in highly-ordered pyrolitic graphite with time-dependent electrical resistance measurements
Authors: Montgomery Jeffrey M. , Kiefer Boris , Lee Kanani K. M.
Published: September 2011

Long-duration, high-pressure resistance measurements on highly-ordered pyrolytic graphite in a diamond-anvil cell show a sluggish phase transition occurring at ∼19 GPa, as evidenced by the time-dependent behavior of the sample resistance. The instantaneous resistance response to pressure adjustment shows a ∼10 GPa hysteresis that has been observed previously, rendering the conjectured direct relationship between resistance and phase-transition tentative. In contrast, the evolution of the resistance with time after the instantaneous response shows a systematic, reproducible, and distinct behavior, which allows reducing the uncertainty in transition pressure to ∼2 GPa. This largely reduced hysteresis shows explicitly that the phase transition is directly related to changes in electronic structure and resistance and establishes consistency with other commonly used experimental techniques to explore phase transitions at high pressures. We augment our experiments with first-principle density-functional theory computations to evaluate the pressure dependence of the electronic density of states of proposed candidate structures for the post-graphite phase.
Heat flux reduction by helical divertor coils in the heliotron fusion energy reactor
Authors: Yanagi N. , Sagara A. , Goto T. , Masuzaki S. , Mito T. , Bansal G. , Suzuki Y. , Nagayama Y. , Nishimura K. , Imagawa S. , Mitarai O.
Published: September 2011

To best utilize the built-in helical divertors in the heliotron-type fusion energy reactor, we propose a new divertor sweeping scheme that reduces both the divertor heat flux and erosion of the divertor plates. This scheme employs a small set of helical coils, which we term helical divertor coils. The divertor legs can be moved by modulating the current amplitude of helical divertor coils by a few per cent of the current amplitude of the main helical coils. Despite the movement of the divertor legs, this scheme changes the magnetic surfaces very little. The strike point width is increased to ∼800 mm and rapid sweeping reduces the time-averaged heat flux to a <1 MW m−2 level with a total power flow of ∼600 MW to the divertor regions for a fusion power of 3 GW. Divertor plate erosion is reduced, enabling the replacement cycle to be significantly prolonged. We propose that the helical divertor coils be fabricated using YBCO high-temperature superconductors and be constructed in prefabricated segments that are joined on site.