bluuebunny/crossref_metadata_2025 huggingface dataset:
Joining of Ti3SiC2 by Magnetron Sputtering a Layer of Cu or Zr Followed by Heat Treating at Relatively Low Temperatures
Authors: Li Aijun , Zhou Yanchun
Published: April 2011

Ti3SiC2 joining has been successfully achieved by depositing a thin Cu or Zr layer on it and heat treating at low temperatures of 950° or 1100°C in an argon atmosphere, respectively, which are ∼500°C lower than the previous solid solution joining method. X‐ray diffraction and scanning electron microscope analyses reveal that a continuous Cu3Si or Zr‐silicide layer forms at the joint interface through the outward diffusion of Si atoms from the Ti3SiC2 substrate into the deposited Cu or Zr layer. The strength of joints is evaluated by tensile bond‐strength test and 4‐point bending test methods. The Ti3SiC2/Cu/Ti3SiC2 joints always fail from the substrate instead of from the bonding interface, while the Ti3SiC2/Zr/Ti3SiC2 joints fail from the joint interface during tensile bond‐strength test. The 4‐point bending strength of Ti3SiC2/Cu/Ti3SiC2 joints reaches a value of 238 MPa, which is 68% of the Ti3SiC2 substrate. So joining using a Cu or Zr film as the interlayer followed by heat treating is a practical and efficient method for joining Ti3SiC2.
Lithium Storage Properties of Porous Carbon Formed Through the Reaction of Supercritical Carbon Dioxide with Alkali Metals
Authors: Wei Lingzhi , Chen Qianwang , Kong Xiangkai
Published: April 2011

Porous carbon produced by reduction of supercritical carbon dioxide with alkali metals was used as anode material of lithium (Li) ion batteries. X‐ray diffraction, field‐emission scanning electron microscope, transmission electron microscope, and electron diffraction were used to characterize the structure of the products. It is shown that the products are consisted of graphite particles with relatively low graphitization and hold regular porous morphology. The porous carbon materials were evaluated as Li ion battery anodes. It exhibits a giant first discharge capacity of 1704 mAh/g at a constant current density of 0.20 mA/cm2, while the reversible capacity decreased to 200 mAh/g. The possible origins of the irreversible capacity of porous carbons and improvement method were discussed.
Lack of preventing effect of systemically and topically administered histamine H1 or H4 receptor antagonists in a dog model of acute atopic dermatitis
Authors: Bäumer Wolfgang , Stahl Jessica , Sander Kerstin , Petersen Lars J. , Paps Judy , Stark Holger , Kietzmann Manfred , Olivry Thierry
Published: April 2011

As there is evidence for an anti‐inflammatory efficacy of histamine H4 receptor (H4R) selective antagonists, we aimed at testing the efficacy of the H4R antagonists JNJ7777120 and JNJ28307474 in comparison with histamine H1 receptor (H1R) antagonists hydroxyzine and cetirizine for skin lesion prevention in a canine model of acute atopic dermatitis. Six atopic Maltese‐beagle dogs experimentally sensitized to Dermatophagoides farinae (Df) house dust mites were selected for this study. Twenty‐four hours after challenge by epicutaneous application of Df, erythematous skin lesions were scored. In this blinded, placebo and active controlled study, topical JNJ7777120 or JNJ28307474 was applied as a 1% solution before allergen challenge. The latter was also given orally at 15 mg/kg before and after allergen challenge. A 0.015% triamcinolone acetonide solution was used as a positive control. The H1R antagonists hydroxyzine and cetirizine were administered orally before challenge in a second experiment. Twenty‐four hours after challenge, placebo‐treated animals had a median lesional score of 2. Treatment with topical and oral JNJ28307474 resulted in a median score of 2.5. After topical administration of JNJ7777120, the median lesional score was 2. Hydroxyzine and cetirizine did also not reduce the median score of the placebo treatment. Triamcinolone acetonide prevented all dogs from having any lesions. Determination of histamine in lesions revealed that only during the initiation increased concentrations of histamine were detected. In conclusion, the preventive administration of H1R or H4R antagonists has no impact on the development of acute skin lesions in this experimental canine atopic dermatitis model.
Val66Met polymorphism and serum brain-derived neurotrophic factor concentration in depressed patients
Authors: Zhang Xiao-bin , Wang Xin , Sha Wei-wei , Zhou Hong-hui , Zhang Yu-mei
Published: April 2011

Zhang X, Wang X, Sha W, Zhou H, Zhang Y. Val66Met polymorphism and serum brain-derived neurotrophic factor concentration in depressed patients.

Objective:Accumulating evidence has suggested a pathophysiological role for brain-derived neurotrophic factor (BDNF) in major depressive disorder (MDD). The present study evaluated serum levels of BDNF and explored whether Val66Met BDNF gene polymorphism is correlated with changes in circulating BDNF levels in patients with MDD and control subjects.

Methods:Subjects were 76 patients with MDD and 50 controls. Diagnosis of MDD was determined by the use of a structured clinical interview according to Diagnostic and Statistical Manual of Mental Disorder-IV (DSM-IV) criteria. The concentrations of BDNF were measured by using the enzyme-linked immunosorbent assay. The Val66Met BDNF gene polymorphism was examined by the polymerase chain reaction technique.

Results:Serum BDNF was significantly lower in MDD patients than in normal control subjects (p< 0.001). There were no significant differences either in allele or genotype in the Val66Met polymorphism between the MDD and control groups. Moreover, genotype did not significantly correlate with the BDNF serum levels in the MDD or control groups.

Conclusions:Our study suggests that there is a decrease in serum BDNF levels in untreated MDD patients. However, serum BDNF levels were not associated with the Val66Met polymorphism.
Translucency of Value Resin Composites Used to Replace Enamel in Stratified Composite Restoration Techniques
Authors: SCHMELING MAX , DE ANDRADA MAURO AMARAL CALDEIRA , MAIA HAMILTON PIRES , DE ARAÚJO EDSON MEDEIROS
Published: April 2011

Background:  The translucency of enamel shade is a crucial property that affects the color of a layered restoration.

Objective:  This study evaluated the translucency of high‐, medium‐, and low‐value resin composites (4 Seasons, Ivoclar Vivadent, Schaan, Liechtenstein) used to replace enamel in stratified composite restoration techniques.

Materials and Methods:  The color specimens with 12 mm in diameter and various thicknesses (0.5, 1.0, 1.5, 2.0, 3.0, 4.0 mm) were measured after polymerization on a reflection spectrophotometer over white and black backgrounds to calculate the translucency parameter (TP). The statistical analysis of TP was accomplished using two‐way analysis of variance (p < 0.05). Significant differences were revealed by the Tukey's Honestly Significant Difference post hoc test.

Results:  Translucency of the value composite resins was influenced by the value and thickness. Color of value resin composites was dependent on the background contrast at the evaluated thicknesses.

Conclusions:  High‐value composite resins were more translucent than medium‐value composites, which were more translucent than low‐value composites. The translucency decreased as the thickness of the specimens increased.

CLINICAL SIGNIFICANCE

The results suggest that special attention should be paid to the thickness of the increment of value composite resins when reproducing translucency of natural tooth enamel.
Levels of reactive oxygen metabolites in patients with knee osteoarthritis
Authors: Kotani Kazuhiko , Sakane Naoki , Kamimoto Munetada , Taniguchi Nobuyuki
Published: April 2011

Aim:  Oxidative stress may be associated with the pathophysiology of knee osteoarthritis (OA), a health‐care issue. The present study aimed to compare oxidative status levels of patients with and without knee OA, using the Reactive Oxygen Metabolites (d‐ROMs, Diacron, Italy) test, which has proved to be clinically useful as an oxidative stress marker.

Methods:  Forty‐nine women (mean age 71.3 ± 5.8 years, mean body mass index 24.4 ± 2.2 kg/m2) with mildly severe knee OA and 49, without knee OA, female controls' serum d‐ROMs concentrations were assessed together with mean blood pressure, fasting plasma glucose and serum total cholesterol concentrations, using the age‐, sex‐ and body mass index‐matched method.

Results:  Patients with knee OA showed significantly higher d‐ROMs levels than controls (338 ± 56 vs 315 ± 47 U. Carr., P < 0.05). This difference remained statistically significant after adjusting for other clinical variables.

Conclusions:  The present results suggested that knee OA might be an impaired oxidative condition. Further studies are necessary to establish the knee OA–oxidative status relationship, which may lead to its clinical application in the management of knee OA.
The application of ecological thinking to better understand the needs of communities of older people
Authors: Harris Neil , Grootjans John
Published: April 2011

Aim:  This research applied ecological thinking to develop a more integrated or ecological understanding of the needs and aspirations of communities of older people.

Methods:  A three‐stage methodology was utilised. Stage one entailed the thematic analysis of resident satisfaction surveys collected from 1000 residents of aged living and care facilities to identify issues impacting upon their lives. In stage two these findings were critiqued through a key stakeholder forum. In stage three findings were authenticated through resident interviews and workshops.

Results:  The findings suggest that an ecological framework for the well‐being of older people living in residential communities can be conceptualised as the four domains of the physical environment, social environment, governance and active living.

Conclusions:  This framework for the ecology of resident well‐being developed through this research informs an ecological approach to service providers' planning to promote the health and well‐being of residents of communities of older people.
Quality of life for older people in residential care is related to connectedness, willingness to enter care, and co‐residents
Authors: Wilkinson Tim J , Kiata Liz J , Peri Kathy , Robinson Elizabeth M , Kerse Ngaire M
Published: April 2011

Aim:  To establish associations with quality of life (QOL) of older people in long‐term residential care facilities in two New Zealand cities.

Methods:  The outcome measure of QOL was the Life Satisfaction Index. We used multiple linear regression to explore how broad categories of factors might contribute to QOL.

Results:  A total of 599 people (median age of 85 years; 74% women) participated. Response rates were 85% for facilities and 83% for residents. A resident's QOL was significantly related to the QOL of co‐residents. QOL was higher for people who were more positive about entry to residential care, more physically able, and not depressed, and for those with more family and emotional support.

Conclusion:  Attending to the circumstances around entry to residential care may enhance QOL, as may promoting physical activity, treating depression and ensuring older people remain emotionally connected to their families. In choosing a facility, noting the QOL of co‐residents is important.
Dedicated teaching block for undergraduate geriatric medicine improves knowledge
Authors: Visvanathan Renuka , Silakong Teena , Yu Solomon
Published: April 2011

Aim:  This paper describes the performance of 5th year medical students in multiple choice question (MCQ) examinations before and after a geriatric medicine teaching block.

Methods:  A 30‐question MCQ test was administered at the start and a 45‐question one at the end of the course.

Results:  There was a statistically significant improvement in the MCQ scores from a mean of 62% (SD 10.4) to 75.2% (SD 7.9) (P < 0.001). Total mean scores for the University of California, Los Angeles (UCLA) Geriatrics Knowledge test improved from 65% (SD 10.4) to 73%(SD 11.7) (P < 0.001). Total mean scores for the American Geriatric Society (AGS) Geriatrics Review Syllabus MCQs improved from 59.3% (SD 17.0) to 78.1% (SD 12.1) (P < 0.001). Post‐course, students scored equally well in the new questions, the validated UCLA test and the AGS questions.

Conclusion:  An undergraduate geriatric medicine clinical teaching block in senior clinical years can increase students' knowledge in geriatric medicine.
Growth and Properties of Core‐Shelled SiC–SiO2 Nanowires Using Chemical Vapor Deposition
Authors: Liao Kun‐Hou , Wu Wan‐Yu , Yang Bol‐Wen , Ting Jyh‐Ming
Published: April 2011

Core‐shelled SiC–SiO2 nanowires have been synthesized on mechanically scratched Si substrates using a catalyst‐assisted chemical vapor reaction process at 1100°C. The average diameter and length are 30 nm and in the order of 101 μm, respectively. The SiC core exhibits a single crystalline structure, while the core is amorphous. High‐resolution transmission electron microscopy images and selected area diffraction patterns show that the (111) planes of the SiC are at an angle of approximately 71° to the nanowires axis. The existence of the SiO2 alters the cathodoluminescence spectra of the SiC nanowires. A growth mechanism is also suggested.
Room Temperature Deposition of Lead Zirconate Titanate on Polymer as Part of a Magnetic Resonance Imaging Marker
Authors: Schimpf Stefan , Brose Andreas , Schmidt Bertram
Published: April 2011

This paper reports on the fabrication of lead zirconate titanate containing layers as a dielectric on three‐dimensional polymer substrates. These layers enable the fabrication of tracking devices to visualize catheters in magnetic resonance imaging (MRI) during interventions. Starting with the motivation and theoretical background the functionality of MRI markers is detailed. One of the main challenges is the reliable and repeatable application of an integrated passive layer having a sufficient permittivity on a cylindrical polymer surface. A technology based on aerosol deposition is presented on two‐dimensional substrates. The layer properties are examined and the results are applied to three‐dimensional cylindrical substrates.
Bonding SiC to SiC Using a Sodium Silicate Solution
Authors: Preston Alix , Mueller Guido
Published: April 2011

This paper describes a simple way to bond SiC parts with a bond thickness of <17 μm that produce shear strengths of several MPa using only a small amount of sodium silicate solution. Several SiC materials with different surface roughnesses were tested for the bonding process and a variety of tests (including thermally cycling the bond and cutting the bonded pieces) were performed to test the durability of the adhesion process. In this paper we explain the bonding procedure, discuss the bonding mechanism, and present shear strength results.
High Performance Planar Solid Oxide Fuel Cell Fabricated with Ni–Yttria Stabilized Zirconia Anode Prepared by Electroless Technique
Authors: Mukhopadhyay Madhumita , Mukhopadhyay Jayanta , Das Sharma Abhijit , Basu Rajendra N.
Published: April 2011

Nickel (Ni)–8 mol% yttria stabilized zirconia (YSZ) cermet prepared through novel electroless technique is used as solid oxide fuel cell anode. The developed anode (28 vol% Ni) is used in two different configurations, viz. anode support and anode active layer (AAL). Highest electrochemical performance of 3.2 A/cm2 with lowest cell area specific resistance (∼94 mΩ cm2) at 800°C is obtained from anode‐supported single cell having an optimized 15 μm electroless AAL. Electrochemical performances are correlated with anode pore‐size distributions. Such high performance cells also exhibit significant low degradation rate (∼2% 1000 h−1 at a load 0.5 A/cm2) during long‐term testing.
Magnifying loupes versus surgical microscope in endodontic surgery: A four‐year retrospective study
Authors: Taschieri Silvio , Weinstein Tommaso , Tsesis Igor , Bortolin Monica , Del Fabbro Massimo
Published: April 2011

The purpose of this retrospective study was to evaluate the 4‐year outcome of endodontic microsurgery using two different magnification devices. One‐hundred and two teeth in 65 patients were included according to specific selection criteria. Endodontic surgery was performed under surgical microscope as magnification device in 63 teeth in 36 patients, while 39 teeth in 29 patients were treated under magnifying loupes. Thirteen patients did not attend the 4‐year follow up. The overall success rate on a patient basis was 91.7% at the 1‐year and 90.5% at the 4‐year follow up for the group using loupes, while for the group using microscope it was 91.4% at the 1‐year and 93.3% at the 4‐year follow up. The relative risk was 2.07 (95% confidence interval: 0.31, 13.95) in favour of the group in which microscope was used. No statistically significant difference was found in the treatment outcomes relating to the type of magnification device.
Optimization of Ultrasonic‐Assisted Enzymatic Hydrolysis for the Extraction of Luteolin and Apigenin from Celery
Authors: Zhang Qian , Zhou Ming‐Ming , Chen Pei‐Lin , Cao Yun‐Ying , Tan Xiang‐Ling
Published: April 2011

Abstract:  The extraction of flavonoids is of increasing interest because of their various pharmacological effects. This study is the first attempt for the ultrasonic‐assisted enzymatic hydrolysis (USAEH) applied in the extraction of 2 bioactive flavonoid compounds in celery—luteolin and apigenin. The quantitative yields of luteolin and apigenin were determined by high‐performance liquid chromatography (HPLC). To achieve high yields of extracted compounds, the procedure was optimized with regard to the relative parameters involved. The optimal conditions for enzymatic hydrolysis using pectinase treatment were a reaction time of 30 min and a concentration of 0.4 mg/mL at pH 3 for luteolin and pH 5.5 for apigenin. The optimal ultrasonic parameters were an exposure period of 30 min at a temperature of 25 °C using a power source of 80 W. Under these optimal conditions, the yields of luteolin and apigenin were increased to 42.5 and 25.3 mg/g, respectively, which represented a 26.1‐fold and a 32.2‐fold increase in the yields of these 2 compounds, respectively, compared with the control model of aqueous extraction without enzyme or ultrasonic treatment.
Volatile Profile of Cashews (Anacardium occidentale L.) from Different Geographical Origins during Roasting
Authors: Agila Amal , Barringer Sheryl Ann
Published: April 2011

Abstract:  Volatile compounds were quantified in the headspace of Indian, Vietnamese, and Brazilian cashews, both raw and during roasting by selected ion flow tube‐mass spectrometry. The optimum roasting times based on color measurements were also determined. Raw cashews were oil roasted for 3 to 9 min at 143 °C and color and volatiles measured. An excellent correlation, following a pseudo 1st‐order reaction, was found between L* value and roasting time; darkness increases as roasting time increases. The optimum roasting time was 6, 8, and 9 min for Vietnamese, Indian, and Brazilian cashews, respectively. Raw cashews had lower concentrations of volatiles than roasted cashews. Most volatiles significantly increased in concentration during roasting of Brazilian, Indian, and Vietnamese cashews. Only a few volatiles significantly decreased during roasting. Ethanol and 1‐heptene significantly decreased during roasting in Brazilian cashews and toluene decreased in Vietnamese cashews. Brazilian cashews had significantly higher levels of most volatiles than Indian and Vietnamese cashews. Most volatile levels in Indian and Vietnamese cashews were not significantly different. Of the volatiles, Strecker aldehydes, including methylbutanal, 2‐methylpropanal, and acetaldehyde, were at the highest concentration in roasted cashews. The Maillard reaction contributed to the formation of most of the volatiles in cashews from the 3 countries. There was also degradation of sugars to form furan‐type compounds and oxidation of lipids to form alkanals such as hexanal.

Practical Application:  The volatile profile during roasting of cashews can be used to determine the best roasting time for each type of cashew. The rate of color development and the production of volatiles differ for the cashews from the 3 geographical locations.
Seasonal Changes of α‐Tocopherol in Green Marine Algae (Caulerpa genus)
Authors: Pires‐Cavalcante Kelma Maria dos Santos , de Alencar Daniel Barroso , de Sousa Márcia Barbosa , Sampaio Alexandre Holanda , Saker‐Sampaio Silvana
Published: April 2011

Abstract:  Marine algae are a promising source of beneficial compounds for human use. Among these, pro‐vitamin A carotenoids and vitamins B, C, and E stand out. The objective of this study was to investigate seasonal variation of α‐tocopherol levels in 5 species of green marine algae of the Caulerpa genus. This research was carried out with both fresh and dry specimens; and, in addition, differences arising as a result of the drying process were examined. Analyses were carried out by high‐performance liquid chromatography (HPLC) using an isocratic system and a reversed‐phase C‐18 column. The distribution of α‐tocopherol throughout the year in Caulerpa genus was variable. All samples of both fresh and dried algae contained α‐tocopherol, except for the dried C. racemosa from March 2006. The drying process was responsible for losses of α‐tocopherol ranging from 21% to 93%.
The relationship between impulsivity and vocational outcome in outpatient youth with borderline personality features
Authors: Sio In Teng , Chanen Andrew M. , Killackey Eóin J. , Gleeson John
Published: April 2011

Aim: This study aims to examine the relationship between each Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM‐IV) borderline personality feature and vocational outcome (i.e. employment and education) in a sample of young people diagnosed with borderline personality pathology.

Methods: The sample comprised 60 young people registered with a specialist early intervention programme for borderline personality disorder (BPD). Diagnostic data and vocational information were obtained from a standardized semistructured assessment and medical record review for a period of 12 months from entry into the treatment programme.

Results: DSM‐IV criterion 4 ‘impulsivity’ upon entry to the treatment programme was associated with poor vocational outcome 12 months after index assessment.

Conclusions: Although the results of the present study suggest that impulsivity is an important feature predictive of vocational functioning in BPD, and that specific intervention in impulsivity might be a critical goal for early intervention of BPD to maximize functional recovery for such patients, further studies are required to test the reliability and validity of the role of impulsivity in relation to vocational outcome of these patients.
Locus‐dependent selection in crop‐wild hybrids of lettuce under field conditions and its implication for GM crop development
Authors: Hooftman Danny A. P. , Flavell Andrew J. , Jansen Hans , den Nijs Hans C. M. , Syed Naeem H. , Sørensen Anker P. , Orozco‐ter Wengel Pablo , van de Wiel Clemens C. M.
Published: April 2011

Gene escape from crops has gained much attention in the last two decades, as transgenes introgressing into wild populations could affect the latter’s ecological characteristics. However, different genes have different likelihoods of introgression. The mixture of selective forces provided by natural conditions creates an adaptive mosaic of alleles from both parental species. We investigated segregation patterns after hybridization between lettuce (Lactuca sativa) and its wild relative, L. serriola. Three generations of hybrids (S1, BC1, and BC1S1) were grown in habitats mimicking the wild parent’s habitat. As control, we harvested S1 seedlings grown under controlled conditions, providing very limited possibility for selection. We used 89 AFLP loci, as well as more recently developed dominant markers, 115 retrotransposon markers (SSAP), and 28 NBS loci linked to resistance genes. For many loci, allele frequencies were biased in plants exposed to natural field conditions, including over‐representation of crop alleles for various loci. Furthermore, Linkage disequilibrium was locally changed, allegedly by selection caused by the natural field conditions, providing ample opportunity for genetic hitchhiking. Our study indicates that when developing genetically modified crops, a judicious selection of insertion sites, based on knowledge of selective (dis)advantages of the surrounding crop genome under field conditions, could diminish transgene persistence.
Small‐group, computer‐mediated argumentation in middle‐school classrooms: The effects of gender and different types of online teacher guidance
Authors: Asterhan Christa S. C. , Schwarz Baruch B. , Gil Julia
Published: April 2011

Background.  Research has shown the importance of careful teacher support during collaborative group work to promote productive discourse between students (Webb, 2009). However, this research has traditionally focused on face‐to‐face communication. The role of online teacher guidance of small‐group computer‐mediated discussions has received little attention, especially in secondary school classroom settings. Researchers of computer‐supported collaborative learning (CSCL), on the other hand, have traditionally focused on software‐embedded features, such as scripts, to support a‐synchronous peer dialogue, and less so on human guidance of synchronous group discussions.

Aims.  The main aim of the present in vivo, experimental study is to examine whether online teacher guidance can improve the quality of small‐group synchronous discussions, and whether different types of guidance (epistemic or interaction guidance) affect these discussions differently, when compared to an unguided condition. The second goal of this study is to explore potential differences between all‐female and all‐male discussion groups.

Sample.  Eighty‐two 9th graders (three classrooms) and six teachers from a rural high school in Israel.

Results.  Whereas epistemic guidance only improved aspects of the argumentative quality of the discussion, interaction guidance only improved aspects of collaboration. Discussions of all‐girls groups scored higher on aspects of collaboration and argumentative quality, compared to all‐boys groups.

Conclusions.  The findings show that teacher guidance of synchronous, online discussions in classrooms is realizable and reasonably reaches its intended goals. Training should be focused on acquiring various guidance strategies to augment their beneficial effects. Furthermore, future research should pay more attention to potential gender differences in peer‐to‐peer argumentation.
The relative importance of two different mathematical abilities to mathematical achievement
Authors: Nunes Terezinha , Bryant Peter , Barros Rossana , Sylva Kathy
Published: April 2011

Background.  Two distinct abilities, mathematical reasoning and arithmetic skill, might make separate and specific contributions to mathematical achievement. However, there is little evidence to inform theory and educational practice on this matter.

Aims.  The aims of this study were (1) to assess whether mathematical reasoning and arithmetic make independent contributions to the longitudinal prediction of mathematical achievement over 5 years and (2) to test the specificity of this prediction.

Sample.  Data from Avon Longitudinal Study of Parents and Children (ALSPAC) were available on 2,579 participants for analyses of KS2 achievement and on 1,680 for the analyses of KS3 achievement.

Method.  Hierarchical regression analyses were used to assess the independence and specificity of the contribution of mathematical reasoning and arithmetic skill to the prediction of achievement in KS2 and KS3 mathematics, science, and English. Age, intelligence, and working memory (WM) were controls in these analyses.

Results.  Mathematical reasoning and arithmetic did make independent contributions to the prediction of mathematical achievement; mathematical reasoning was by far the stronger predictor of the two. These predictions were specific in so far as these measures were more strongly related to mathematics than to science or English. Intelligence and WM were non‐specific predictors; intelligence contributed more to the prediction of science than of maths, and WM predicted maths and English equally well.

Conclusions.  There is clear justification for making a distinction between mathematical reasoning and arithmetic skills. The implication is that schools must plan explicitly to improve mathematical reasoning as well as arithmetic skills.
Multiple contributions to priming effects for familiar faces: Analyses with backward masking and event‐related potentials
Authors: Dörr Peggy , Herzmann Grit , Sommer Werner
Published: April 2011

The model of face recognition by Bruce and Young postulates a pool of structural representations for familiar faces in long‐term memory, so‐called face recognition units (FRUs). Event‐related brain potentials show early repetition priming effects for familiar faces around 250–300 ms [N250r or early repetition effect (ERE)], which are thought to reflect the activation of these FRUs. However, small N250r effects are also seen for unfamiliar faces suggesting that priming of perceptual codes (i.e., pictorial and structural codes) also contributes to early repetition effects. Using a face‐familiarity task in Experiment 1, we aimed to eliminate these perceptual contributions to face priming by backward masking the prime face with a different, unfamiliar face. As expected, a repetition priming effect appeared only for familiar faces. Experiment 2 used a semantic‐decision task and compared the effects of different kinds of masks that interfered with either pictorial codes or with pictorial and structural codes. Our findings indicate that both structural codes and memory representations contribute to the N250r and that unfamiliar‐face masks interfere only with structural codes. Face‐masks may therefore provide a useful tool to extract the pure contributions of memory representations (i.e., FRUs) to repetition priming.
Sarcoplasmic reticulum and L‐type Ca2+ channel activity regulate the beat‐to‐beat stability of calcium handling in human atrial myocytes
Authors: Llach Anna , Molina Cristina E. , Fernandes Jacqueline , Padró Josep , Cinca Juan , Hove‐Madsen Leif
Published: April 2011

Non‐technical summary  Cardiac arrhythmias occur when the heart is unable to beat rhythmically, and can be induced if the heart is forced to work in excess of its capacity. Here we examine how cells isolated from the atrial chamber of the human heart respond when their beating rate is increased. Our results show that there are differences in the ability of individual heart cells to respond rhythmically when they are forced to beat fast. Moreover, we find that mechanisms that regulate the level of calcium ions in the heart cells determine their ability to respond rhythmically. These results show that pharmacological control of calcium levels in heart cells might be useful in the treatment of people who suffer cardiac arrhythmias during excessive exercise.
Proprioceptive signals contribute to the sense of body ownership
Authors: Walsh Lee D. , Moseley G. Lorimer , Taylor Janet L. , Gandevia Simon C.
Published: April 2011

Non‐technical summary  The sense of body ownership tells us that our body belongs to us, and other bodies do not. That our body belongs to us is fundamental to self‐awareness. It is known that synchronous touch and vision can be used to induce an illusion of ownership over an artificial rubber hand. Like the skin receptors used for touch, sensory receptors in the muscles only provide information about events occurring to the body. Whether muscle receptors contribute to our sense of body ownership is not known. This study developed a technique to induce an illusion of ownership over a plastic finger using movement, which excites muscle receptors. This sense of ownership still occurred when the contribution of skin and joint receptors was removed using local anaesthetic. The results clearly show that muscle receptors can contribute to the sense of body ownership.
Robust L‐type calcium current expression following heterozygous knockout of the Cav1.2 gene in adult mouse heart
Authors: Rosati Barbara , Yan Qinghong , Lee Mi Sun , Liou Shian‐Ren , Ingalls Brian , Foell Jason , Kamp Timothy J. , McKinnon David
Published: April 2011

Non‐technical summary  Appropriate regulation of ion channel expression is critical for the maintenance of both electrical stability and normal contractile function in the heart. A classic way to study the robustness of biological systems is to examine the effects of changes in gene dosage. We have studied how the heart responds to changes in the L‐type calcium channel gene dosage. Homozygous Cav1.2 knockout in the adult heart is lethal, without compensatory responses in expression of other calcium channel genes. Following heterozygous knockout, Cav1.2 mRNA levels are not buffered, Cav1.2 membrane protein levels are partly buffered and L‐type calcium current expression is relatively well buffered. These data are consistent with a passive model of Cav1.2 biosynthesis that includes saturated steps, which act to buffer Cav1.2 protein and L‐type calcium current expression. The results suggest that there is little or no homeostatic regulation of calcium current expression in either heterozygous or homozygous knockout mice.
Mechanisms for Wide-Chord Fan Blade Flutter
Authors: Vahdati Mehdi , Simpson George , Imregun Mehmet
Published: April 2011

This paper describes a detailed wide-chord fan blade flutter analysis with emphasis on flutter bite. The same fan was used with three different intakes of increasing complexity to explain flutter mechanisms. Two types of flutter, namely, stall and acoustic flutters, were identified. The first intake is a uniform cylinder, in which there are no acoustic reflections. Only the stall flutter, which is driven by flow separation, can exist in this case. The second intake, based on the first one, has a “bump” feature to reflect the fan’s forward pressure wave at a known location so that detailed parametric studies can be undertaken. The analysis revealed a mechanism for acoustic flutter, which is driven by the phase of the reflected wave. The third intake has the typical geometric features of a flight intake. The results indicate that flutter bite occurs when both stall and acoustic flutters happen at the same speed. It is also found that blade stiffening has no effect on aero-acoustic flutter.
The Tip Clearance Flow Resonance Behind Axial Compressor Nonsynchronous Vibration
Authors: Thomassin Jean , Vo Huu Duc , Mureithi Njuki W.
Published: April 2011

Nonsynchronous vibration (NSV) is a particular type of aero-elastic phenomenon, where the rotor blades vibrate at nonintegral multiples of the shaft rotational frequencies. NSV behavior appears similar to off-design stall flutter but with a particular blade tip flow evolution. This paper demonstrates the link between NSV and the resonance induced by the tip clearance flow based on a proposed hypothesis and experimental confirmation. At off-design operating conditions, the rotor blade tip clearance shear layer flow can evolve tangentially. It is proposed that this tangential flow becomes a support for an acoustic feedback wave that settles between rotor blades. The feedback wave is driven by the blade vibratory motion and synchronizes the shear layer vortical structures with the blade vibration frequency. Depending on the blade tip local temperature, and when the feedback wavelength matches within one or two blade pitches, the system becomes resonant and very high vibrations can occur on the blade. An axial stage compressor test rig is set-up to look into the underlying mechanism behind NSV through targeted measurements using both static and rotating instrumentation. The experimental apparatus consists of the first stage of a high pressure compressor driven by an electric motor. The test-section is built to minimize the effects of the adjacent stator blade rows in order to isolate the role of rotor blade tip clearance flow on NSV. Sensitivity studies are carried out to assess and demonstrate the effects of the rotor blade tip clearance and inlet temperature on NSV and validate the predicted resonance for NSV occurrence under various conditions. Vibrations and surface pressure data from adjacent blades are collected to demonstrate the predicted interactions between neighboring rotor blades. Finally, evidence of the staging phenomenon, inherent to the proposed NSV mechanism, is experimentally obtained. All the data obtained are consistent with and thus in support of the proposed mechanism for NSV.
Differential Metabolic Impact of Gastric Bypass Surgery Versus Dietary Intervention in Obese Diabetic Subjects Despite Identical Weight Loss
Authors: Laferrère Blandine , Reilly David , Arias Sara , Swerdlow Nicholas , Gorroochurn Prakash , Bawa Baani , Bose Mousumi , Teixeira Julio , Stevens Robert D. , Wenner Brett R. , Bain James R. , Muehlbauer Michael J. , Haqq Andrea , Lien Lillian , Shah Svati H. , Svetkey Laura P. , Newgard Christopher B.
Published: April 2011

The enhanced decrease in circulating branched-chain amino acids and their metabolites after gastric bypass occurs by mechanisms other than weight loss.
Two Roads Diverge: Weight Loss Interventions and Circulating Amino Acids
Authors: Gerszten Robert E. , Wang Thomas J.
Published: April 2011

Gastric bypass surgery decreases circulating amino acid concentrations by mechanisms separate from weight loss.
Sperm Find Culture
Authors: Evans-Molina Carmella
Published: April 2011

Cultured neonatal mouse testes produce functional mature sperm, an advance that one day may be useful for treating male infertility.
Habitat loss, climate change, and emerging conservation challenges in Canada1This review is part of the virtual symposium “Flagship Species – Flagship Problems” that deals with ecology, biodiversity and management issues, and climate impacts on species at risk and of Canadian importance, including the polar bear (Ursus maritimus), Atlantic cod (Gadus morhua), Piping Plover (Charadrius melodus), and caribou (Rangifer tarandus).
Authors: Coristine Laura E. , Kerr Jeremy T.
Published: April 2011

In Canada, habitat loss has pushed many more species to the brink of extinction than expected in a region with extensive wilderness. However, species richness gradients depend strongly on climate, so species are concentrated in southern regions, where agricultural and urban land uses are both intensive and extensive. Agricultural pesticide use is associated with increasing rates of species endangerment in the south, but long-range transport of persistent organic pollutants is an emerging issue in remote northern regions. Because their distributions reflect climate so strongly, climate change threatens species throughout Canada. Evidence indicates that species’ distributions, phenologies, and interactions with pests and diseases are changing more rapidly in response to climate change than global mean values. Nevertheless, climate change is expected to impose dispersal requirements that surpass species’ maximum rates. Habitat losses may interact with climate change to impair species’ dispersal still further, creating the potential for widespread disruption of biological systems in the most diverse areas of Canada. New research is urgently needed to address questions, and the ethics, around species translocation, ecosystem engineering to anticipate future environmental conditions, and strategies to facilitate the persistence of rare species in landscapes dominated by human activities.
STRING COSMOLOGY IN ANISOTROPIC BIANCHI-II SPACETIME
Authors: KUMAR SURESH
Published: April 2011

The present study deals with a spatially homogeneous and anisotropic Bianchi-II cosmological model representing massive strings. The energy–momentum tensor, as formulated by Letelier,10 has been used to construct a massive string cosmological model for which the expansion scalar is proportional to one of the components of shear tensor. The Einstein's field equations have been solved by applying a variation law for generalized Hubble's parameter that yields a constant value of deceleration parameter in Bianchi-II spacetime. A comparative study of accelerating and decelerating modes of the evolution of universe has been carried out in the presence of string scenario. The study reveals that massive strings dominate the early Universe. The strings eventually disappear from the Universe for sufficiently large times, which is in agreement with the current astronomical observations.
NOMINAL CROSS RECURRENCE AS A GENERALIZED LAG SEQUENTIAL ANALYSIS FOR BEHAVIORAL STREAMS
Authors: DALE RICK , WARLAUMONT ANNE S. , RICHARDSON DANIEL C.
Published: April 2011

We briefly present lag sequential analysis for behavioral streams, a commonly used method in psychology for quantifying the relationships between two nominal time series. Cross recurrence quantification analysis (CRQA) is shown as an extension of this technique, and we exemplify this nominal application of CRQA to eye-movement data in human interaction. In addition, we demonstrate nominal CRQA in a simple coupled logistic map simulation used in previous communication research, permitting the investigation of properties of nonlinear systems such as bifurcation and onset to chaos, even in the streams obtained by coarse-graining a coupled nonlinear model. We end with a summary of the importance of CRQA for exploring the relationship between two behavioral streams, and review a recent theoretical trend in the cognitive sciences that would be usefully informed by this and similar nonlinear methods. We hope this work will encourage scientists interested in general properties of complex, nonlinear dynamical systems to apply emerging methods to coarse-grained, nominal units of measure, as there is an immediate need for their application in the psychological domain.
HOW TO AVOID POTENTIAL PITFALLS IN RECURRENCE PLOT BASED DATA ANALYSIS
Authors: MARWAN NORBERT
Published: April 2011

Recurrence plots and recurrence quantification analysis have become popular in the last two decades. Recurrence based methods have on the one hand a deep foundation in the theory of dynamical systems and are on the other hand powerful tools for the investigation of a variety of problems. The increasing interest encompasses the growing risk of misuse and uncritical application of these methods. Therefore, we point out potential problems and pitfalls related to different aspects of the application of recurrence plots and recurrence quantification analysis.
RECURRENCE-BASED TIME SERIES ANALYSIS BY MEANS OF COMPLEX NETWORK METHODS
Authors: DONNER REIK V. , SMALL MICHAEL , DONGES JONATHAN F. , MARWAN NORBERT , ZOU YONG , XIANG RUOXI , KURTHS JÜRGEN
Published: April 2011

Complex networks are an important paradigm of modern complex systems sciences which allows quantitatively assessing the structural properties of systems composed of different interacting entities. During the last years, intensive efforts have been spent on applying network-based concepts also for the analysis of dynamically relevant higher-order statistical properties of time series. Notably, many corresponding approaches are closely related to the concept of recurrence in phase space. In this paper, we review recent methodological advances in time series analysis based on complex networks, with a special emphasis on methods founded on recurrence plots. The potentials and limitations of the individual methods are discussed and illustrated for paradigmatic examples of dynamical systems as well as for real-world time series. Complex network measures are shown to provide information about structural features of dynamical systems that are complementary to those characterized by other methods of time series analysis and, hence, substantially enrich the knowledge gathered from other existing (linear as well as nonlinear) approaches.
INNOVATION TO IMPACT IN A TIME OF RECESSION
Authors: LEIGHTON TIMOTHY G.
Published: April 2011

Whilst most people in developed societies would celebrate the route from innovation to impact, particularly in the context of engineering and biomedicine, it is not often acknowledged that the definitions of the start, mid-points and even end-points of that route vary between groups in society. Since that route requires funding, this variety of opinion leaves regions of the route vulnerable to underfunding, particularly in times of recession. This paper explores how this can lead to failure to foresee problems and underpin solutions on the 10–50 year timescale. Furthermore, policies designed to support the route from innovation to impact can have the opposite effect. The route is illustrated with examples from the author's research.
AN EIGENVALUE SEARCH ALGORITHM FOR THE MODAL ANALYSIS OF A RESONATOR IN FREE SPACE
Authors: FUß STEFANIE , HAWKINS STUART C. , MARBURG STEFFEN
Published: April 2011

In this article we present an algorithm for the three-dimensional numerical simulation of the sound spectrum and the propagation of acoustic radiation inside and around long slender hollow objects. The fluid inside and close to the object is meshed by Lagrangian tetrahedral finite elements. To obtain results in the far field of the object, complex conjugated Astley-Leis infinite elements are used. To apply these infinite elements the finite element domain is meshed either in a spherical or an ellipsoidal shape. Advantages and disadvantages of both shapes regarding the form of the object are discussed in this article. The formulation leads to a quadratic eigenvalue problem with real, large and nonsymmetric matrices. An eigenvalue search algorithm is implemented to concentrate on the computation of the interior eigenmodes. This algorithm is based on a linearization of the quadratic problem in a state space formulation. The search algorithm uses a complex shift to efficiently extract the relevant eigenvalues only.
LARGE SCALE SIMULATION OF WAVE PROPAGATION IN SOILS INTERACTING WITH STRUCTURES USING FEM AND SBFEM
Authors: SCHAUER MARCO , LANGER SABINE , ROMAN JOSE E. , QUINTANA-ORTÍ ENRIQUE S.
Published: April 2011

This paper applies a parallel algorithm for a coupled Finite Element/Scaled Boundary Element (FEM/SBFEM)-approach to study soil-structure-interaction problems. The application code is designed to run on clusters of computers, and it enables the analysis of large-scale problems. A crucial point of the approach is that the SBFEM fulfills the radiation condition. Hence, the hybrid numerical approach is well suited for such problems where wave propagation to infinity in an unbounded domain must be considered. The main focus of the paper is to show the applicability of the numerical implementation on large scale problems. First the coupled FEM/SBFEM approach is validated by comparing the numerical results with a semi-analytical solution for a settlement problem. Then the implemented algorithm is applied to study the dynamical behavior of founded wind energy plants under time dependent loading.
NONDEGENERACY OF THE PERIODICALLY FORCED LIÉNARD DIFFERENTIAL EQUATION WITH ϕ-LAPLACIAN
Authors: TORRES P. J.
Published: April 2011

New results on the existence of periodic solutions of a forced Liénard differential equation with ϕ-Laplacian are provided. The method of proof relies on the Schauder fixed point theorem, so some information on the location of the solutions is also obtained, leading to multiplicity results. The flexibility of this approach is tested by comparing our results with some examples taken from the related literature, including the classical pendulum equation.