bluuebunny/crossref_metadata_2025 huggingface dataset:
Superconductivity at 14.6 K in Fe(SeTe) single crystal and the role of excess Fe
Authors: Cao Shixun , Shen Shaoxi , Chen La , Yuan Shujuan , Kang Baojuan , Zhang Jincang
Published: August 2011

Fe1.01Se0.38Te0.62 single crystal was successfully grown by self-flux method, and effect of post-annealing technique on structure and superconductivity was also systemically studied. The results show the as-grown sample has an excellent superconductivity with an onset transition temperature Tconset ∼ 14.6 K and a zero resistivity temperature Tczero ∼ 13.4 K. After annealing at 400 °C for 48 h, excess Fe in the post-annealing sample appears with Fe1.06Se0.34Te0.66 formula, and superconductivity was strongly suppressed with Tczero ∼ 8.0 K. The experiments found that excess Fe is located at Fe(2) site with local magnetic moment. According to the Werthamer-Helfand-Hohenberg (WHH) theory, the upper critical fields Hc2 at zero temperature were estimated to be 54.2 T for as-grown sample and 28.2 T for post-annealing sample. Two abnormal drops in DC magnetization are found near 40 K and 125 K for all samples, the one near 40 K may be related to a spin freezing of excess Fe and that near 120 K should be corresponding to the structural transition from tetragonal to monoclinic. This is confirmed by the strain measurement. On the other hand, a kink change of specific heat was also found around 10 K for a post-annealed sample.
Effect of Mn-acceptor dopant on dielectric and piezoelectric responses of lead lanthanum zirconate titanate piezoceramics
Authors: Perez-Delfin E. , García J. E. , Ochoa D. A. , Pérez R. , Guerrero F. , Eiras J. A.
Published: August 2011

Dielectric and direct piezoelectric responses in non-doped and Mn-doped Pb0.91La0.09(Zr0.65,Ti0.35)O3 ceramics are experimentally studied. The permittivity and the direct piezoelectric coefficient were measured by applying an ac electric field or a mechanical stress, respectively. The results show that the dielectric response is mainly due to an extrinsic contribution at room temperature. A notable reduction in room temperature dielectric losses by Mn-doping is verified. The temperature of the minimum of the losses depends on the Mn-content, enabling the Pb0.91La0.09(Zr0.65,Ti0.35)O3 properties to be tuned from soft to hard. A significant stabilization of the dielectric and piezoelectric responses, related to domain wall motion reduction, is confirmed in Mn-doped materials, so these materials become good candidates for transducer applications. The correlation between the dielectric constant and dielectric losses is discussed in terms of the Rayleigh model. Results show that Mn-doped PLZT response does not fit this model. This fact could be explained by taking into account the nature of the defects created by manganese addition. These complex defects act as pinning centers, and the reversible movement of domain walls provide a significant contribution to the response of these materials.
Systematic analyses of vibration noise of a vibration isolation system for high-resolution scanning tunneling microscopes
Authors: Iwaya Katsuya , Shimizu Ryota , Hashizume Tomihiro , Hitosugi Taro
Published: August 2011

We designed and constructed an effective vibration isolation system for stable scanning tunneling microscopy measurements using a separate foundation and two vibration isolation stages (i.e., a combination of passive and active vibration isolation dampers). Systematic analyses of vibration data along the horizontal and vertical directions are present, including the vibration transfer functions of each stage and the overall vibration isolation system. To demonstrate the performance of the system, tunneling current noise measurements are conducted with and without the vibration isolation. Combining passive and active vibration isolation dampers successfully removes most of the vibration noise in the tunneling current up to 100 Hz. These comprehensive vibration noise data, along with details of the entire system, can be used to establish a clear guideline for building an effective vibration isolation system for various scanning probe microscopes and electron microscopes.
Measurement, analysis, and modeling of 1/f noise in pentacene thin film transistors
Authors: Kang Hongki , Jagannathan Lakshmi , Subramanian Vivek
Published: August 2011

In order to facilitate accurate noise modeling of organic thin-film-transistors (OTFTs), we provide comprehensive experimental results and analysis of unique low frequency noise characteristics in OTFTs. We conduct drain current noise measurements for pentacene-based thin-film-transistors (TFTs) having different grain size and operating region and use the resulting data to provide detailed mechanistic understanding of the underlying noise-generation phenomena that exist in OTFTs. The results show carrier trapping by traps within the semiconductor is the dominant source of low frequency noise and can be used in conjunction with a conventional unified noise model to accurately describe the noise behavior of pentacene TFTs.
Thermal resistance of a nanoscale point contact to an indium arsenide nanowire
Authors: Zhou Feng , Persson Ann , Samuelson Lars , Linke Heiner , Shi Li
Published: August 2011

The thermal resistance of a nanoscale point contact to an indium arsenide nanowire was experimentally determined to be two orders of magnitude larger than the theoretical prediction based on the diffuse mismatch model for a welded contact. The discrepancy is attributed mainly to a much smaller phonon transmission coefficient for the weak van der Waals contact than for a welded contact. The experiment further suggests the need of careful examination of the structure and defects in the nanowire sample for similar thermal transport measurements of individual nanowires.
Impulse absorption using small, hard panels of embedded cylinders with granular alignments
Authors: Breindel Alexander , Sun Diankang , Sen Surajit
Published: August 2011

Sustained ability to absorb impulses at varied temperatures using light, hard materials and at length scales of few centimeters has been a challenge. The tapered chains while effective have been difficult to construct for applications. Here we build on Hong’s granular protector concept to show that strong inertial mismatches due to alternate sets of few massive and light grains in elastically matched monosized granular alignments seem promising in absorbing impulses across millisecond time scales within a few centimeters. We propose a system which could find applications in the context of the construction and automobile industries, in combat, and elsewhere.
Negative differential gain due to many body effects in self-assembled quantum dot lasers
Authors: Shahid H. , Childs D. T. D. , Stevens B. J. , Hogg R. A.
Published: August 2011

The gain spectrum of a quantum dot laser operating at 1300 nm is studied at high carrier densities, corresponding to dot occupancies of ∼8 e-h pairs per quantum dot. A reduction in peak gain with increasing carrier density is observed, attributed to the saturation of peak gain, yet the continuous increase in dephasing acting to broaden the individual quantum dot transitions.
Performance evaluation of a solar photovoltaic thermal air collector using energy and exergy analysis
Authors: Sobhnamayan F. , Hamidi A. , Monavari H. R. , Sarhaddi F. , Farahat S. , Alavi M. A.
Published: August 2011

In this article, a comparative study is carried out between two equations for the exergy efficiency of photovoltaic thermal (PV/T) air collectors; the first equation is based on net output exergy and the second equation is in terms of exergy losses. The exergy efficiency equation parametrically is dependent on thermal and electrical parameters of PV/T air collector; therefore, improved thermal and electrical models are used to calculate them. Developing an exergy balance for PV/T air collector system, the various exergy components in PV/T system are introduced and two equations for the exergy efficiency of PV/T air collector are derived. A computer simulation program is also developed which is based on the used improved thermal and electrical models. In order to validate the simulation results, a typical PV/T air collector has been built and some experiments have been carried out on it. The results of numerical simulation are in good agreement with the experimental results. Finally, parametric studies have been carried out and the effect of design and climatic parameters on two exergy efficiency equations has been investigated. It is observed that the improved exergy efficiency obtained in this paper is in good agreement with the one given by the previous literature and it is better because it shows the portion of each of exergy losses in the exergy efficiency equation, directly.
Numerical investigation into the switchable diode effect in metal-ferroelectric-metal structures
Authors: Ge Chen , Jin Kui-Juan , Wang Can , Lu Hui-Bin , Wang Cong , Yang Guo-Zhen
Published: August 2011

A self-consistent numerical model, particularly including the incomplete screening effect of metal electrodes, is introduced to reveal the mechanism of the switchable diode characteristics in metal/ferroelectric/metal structures. The calculated results are in good agreement with recent experimental data, theoretically demonstrating the important role played by the polarization-modulated barrier. Our calculations confirm that electrodes with a smaller permittivity, such as noble metals, are better choices to obtain a more pronounced switchable diode effect, and the barrier height variation as a function of the polarization will deviate from the linear relationship if the carrier concentration induced by the polarization becomes sufficiently high.
Contributions of the US state park system to nature recreation
Authors: Siikamäki Juha
Published: August 2011

Nature recreation in the United States concentrates in publicly provided natural areas. They are costly to establish and maintain, but their societal contributions are difficult to measure. Here, a unique approach is developed to quantifying nature recreation services generated by the US state park system. The assessment first uses data from five national surveys conducted between 1975 and 2007 to consistently measure the amount of time used for nature recreation. The surveys comprise two official federal surveys and their predecessors. Each survey was designed to elicit nationally representative, detailed data on how people divide their time into different activities. State-level data on time use for nature recreation were then matched with information on the availability of state parks and other potentially important drivers of recreation, so that statistical estimation methods for nonexperimental panel data (difference-in-differences) could be used to examine the net contribution of state parks to nature recreation. The results show that state parks have a robust positive effect on nature recreation. For example, the approximately 2 million acres of state parks established between 1975 and 2007 are estimated to contribute annually 600 million hours of nature recreation (2.7 h per capita, approximately 9% of all nature recreation). All state parks generate annually an estimated 2.2 billion hours of nature recreation (9.7 h per capita; approximately 33% of all nature recreation). Using conventional approaches to valuing time, the estimated time value of nature recreation services generated by the US state park system is approximately $14 billion annually.
OrganismTagger: detection, normalization and grounding of organism entities in biomedical documents
Authors: Naderi Nona , Kappler Thomas , Baker Christopher J. O. , Witte René
Published: August 2011

Motivation: Semantic tagging of organism mentions in full-text articles is an important part of literature mining and semantic enrichment solutions. Tagged organism mentions also play a pivotal role in disambiguating other entities in a text, such as proteins. A high-precision organism tagging system must be able to detect the numerous forms of organism mentions, including common names as well as the traditional taxonomic groups: genus, species and strains. In addition, such a system must resolve abbreviations and acronyms, assign the scientific name and if possible link the detected mention to the NCBI Taxonomy database for further semantic queries and literature navigation.

Results: We present the OrganismTagger, a hybrid rule-based/machine learning system to extract organism mentions from the literature. It includes tools for automatically generating lexical and ontological resources from a copy of the NCBI Taxonomy database, thereby facilitating system updates by end users. Its novel ontology-based resources can also be reused in other semantic mining and linked data tasks. Each detected organism mention is normalized to a canonical name through the resolution of acronyms and abbreviations and subsequently grounded with an NCBI Taxonomy database ID. In particular, our system combines a novel machine-learning approach with rule-based and lexical methods for detecting strain mentions in documents. On our manually annotated OT corpus, the OrganismTagger achieves a precision of 95%, a recall of 94% and a grounding accuracy of 97.5%. On the manually annotated corpus of Linnaeus-100, the results show a precision of 99%, recall of 97% and grounding accuracy of 97.4%.

Availability: The OrganismTagger, including supporting tools, resources, training data and manual annotations, as well as end user and developer documentation, is freely available under an open-source license at http://www.semanticsoftware.info/organism-tagger.

Contact:  witte@semanticsoftware.info
EMSY-Like Genes Are Required for Full RPP7-Mediated Race-Specific Immunity and Basal Defense in Arabidopsis
Authors: Tsuchiya Tokuji , Eulgem Thomas
Published: August 2011

The Arabidopsis thaliana gene enhanced downy mildew 2 (EDM2) encodes a nuclear protein required for RPP7-mediated race-specific disease resistance against Hyaloperonospora arabidopsidis, proper floral transition and additional developmental processes. Transcript levels of the disease-resistance gene RPP7 are enhanced by EDM2 while those of the floral suppressor FLC are repressed by EDM2. By yeast two-hybrid screening for EDM2-interacting proteins, we identified AtEML1, a member of a small group of four Arabidopsis proteins containing an EMSY N-terminal domain, a central Agenet domain, and a C-terminal coiled-coil motif. Using T-DNA mutants combined with silencing by artificial microRNAs, we found AtEML1, AtEML2, and, likely, AtEML4 to contribute to RPP7-mediated immunity. Besides this, AtEML1 and AtEML2 participate in a second EDM2-dependent function and affect floral transition. Unlike EDM2, whose role in immunity appears to be limited to RPP7-mediated disease resistance, some AtEML members contribute to basal defense, an unspecific general defense mechanism. Domain architectures of EDM2 as well as AtEML proteins suggest roles of these proteins in the regulation of chromatin states. Thus, possible cooperation of AtEML members with EDM2 at the level of chromatin dynamics may link race-specific pathogen recognition to general defense mechanisms.
Genetic Variability ofRotylenchulus reniformis
Authors: Leach Megan , Agudelo Paula , Lawton-Rauh Amy
Published: August 2011

Rotylenchulus reniformis, reniform nematode, is a polyphagous pest commonly found parasitizing cotton in the southeastern United States. We developed and optimized 10 polymorphic microsatellite loci found in reniform nematode and tested them on 160 individual reniform nematodes to determine informative genetic variation of isolates from the southeastern United States, Colombia, Japan, and from the species Rotylenchulus parvus. No significant gametic disequilibrium was detected between any pair of loci, and most loci were not in expected Hardy-Weinberg proportions. A positive FIScoefficient was observed at all 10 loci, suggesting a high level of inbreeding at these loci. Most isolate locations exhibited significant genotypic differentiation and moderate to very high genetic differentiation based on FSTanalysis. The most consistently differentiated isolates were found reproducing parthenogenetically in Japan. These isolates were also found to represent the most basal locality in this study based on unweighted pair group method with arithmetic mean (UPGMA) clustering analysis and were distinct from other localities based on STRUCTURE V 2.3 analysis. These results support previous reports suggesting that the parthenogenetically reproducing isolates from Japan are another species. Taken together, our results can serve as the foundation for more extensive characterization of population structure and genetic variation among isolates of R. reniformis variants to help discern the impact of alternative processes on genetic connectivity and differentiation in the genetically undercharacterized reniform nematode.
Grapevine leafroll-associated virus 1Occurs as Genetically Diverse Populations
Authors: Alabi Olufemi J. , Al Rwahnih Maher , Karthikeyan Gandhi , Poojari Sudarsana , Fuchs Marc , Rowhani Adib , Naidu Rayapati A.
Published: August 2011

The genetic diversity of 34 isolates of Grapevine leafroll-associated virus 1 (GLRaV-1) from different wine, table, and ornamental grape cultivars in California, New York, and Washington States in the United States was investigated. Segments of the heat-shock protein 70 homolog (HSP70h) gene, coat protein (CP) gene, coat protein duplicate 2 (CPd2) gene, and open reading frame 9 (p24) were amplified by reverse-transcription polymerase chain reaction, cloned, and sequenced. A pairwise comparison of nucleotide sequences revealed intra- and interisolate sequence diversity, with CPd2 and HSP70h being the most and the least divergent, respectively, among the four genomic regions studied. The normalized values for the ratio of nonsynonymous substitutions per nonsynonymous site to synonymous substitutions per synonymous site indicated different purifying selection pressures acting on each of the four genomic regions, with the CP and CPd2 being subjected to the strongest and weakest functional constraints, respectively. A global phylogenetic analysis of sequences from the four genomic regions revealed segregation of GLRaV-1 isolates into three major clades and a lack of clearly defined clustering by geographical origin. In contrast, only two lineages were apparent when the CP and CPd2 gene sequences were used in phylogenetic analyses. Putative recombination events were revealed among the HSP70h, CP, and p24 sequences. The genetic landscape of GLRaV-1 populations presented in this study provides a foundation for better understanding of the epidemiology of grapevine leafroll disease across grape-growing regions in the United States. In addition, this study will benefit grape clean plant programs across the country in improving the sanitary status of planting materials provided to nurseries and grape growers.
Mechanics of peristaltic locomotion and role of anchoring
Authors: Tanaka Yoshimi , Ito Kentaro , Nakagaki Toshiyuki , Kobayashi Ryo
Published: August 2011

Limbless crawling is a fundamental form of biological locomotion adopted by a wide variety of species, including the amoeba, earthworm and snake. An interesting question from a biomechanics perspective is how limbless crawlers control their flexible bodies in order to realize directional migration. In this paper, we discuss the simple but instructive problem of peristalsis-like locomotion driven by elongation–contraction waves that propagate along the body axis, a process frequently observed in slender species such as the earthworm. We show that the basic equation describing this type of locomotion is a linear, one-dimensional diffusion equation with a time–space-dependent diffusion coefficient and a source term, both of which express the biological action that drives the locomotion. A perturbation analysis of the equation reveals that adequate control of friction with the substrate on which locomotion occurs is indispensable in order to translate the internal motion (propagation of the elongation–contraction wave) into directional migration. Both the locomotion speed and its direction (relative to the wave propagation) can be changed by the control of friction. The biological relevance of this mechanism is discussed.
The effect of neutral helper lipids on the structure of cationic lipid monolayers
Authors: Dabkowska A. P. , Barlow D. J. , Hughes A. V. , Campbell R. A. , Quinn P. J. , Lawrence M. J.
Published: August 2011

Successful drug delivery via lipid-based systems has often been aided by the incorporation of ‘helper lipids’. While these neutral lipids enhance the effectiveness of cationic lipid-based delivery formulations, many questions remain about the nature of their beneficial effects. The structure of monolayers of the cationic lipid dimethyldioctadecylammonium bromide (DODAB) alone, and mixed with a neutral helper lipid, either diolelyphosphatidylethanolamine or cholesterol at a 1 : 1 molar ratio was investigated at the air–water interface using a combination of surface pressure–area isotherms, Brewster angle microscopy (BAM) and specular neutron reflectivity in combination with contrast variation. BAM studies showed that while pure DODAB and DODAB with cholesterol monolayers showed fairly homogeneous surfaces, except in the regions of phase transition, monolayers of DODAB with diolelyphosphatidylethanolamine were, in contrast, inhomogeneous exhibiting irregular bean-shaped domains throughout. Neutron reflectivity data showed that while the thickness of the DODAB monolayer increased from 17 to 24 Å as it was compressed from a surface pressure of 5–40 mN m
−1
, the thickness of the helper lipid-containing monolayers, over the same range of surface pressures, was relatively invariant at between 25 and 27 Å. In addition, the monolayers containing diolelyphosphatidylethanolamine were found to be more heavily hydrated than the monolayers of cationic lipid, alone or in combination with cholesterol, with hydration levels of 18 molecules of water per molecule of lipid being recorded for the diolelyphosphatidylethanolamine-containing monolayers at a surface pressure of 30 mN m
−1
compared with only six and eight molecules of water per molecule of lipid for the pure DODAB monolayer and the cholesterol-containing DODAB monolayer, respectively.
Truncated Lévy walks are expected beyond the scale of data collection when correlated random walks embody observed movement patterns
Authors: Reynolds A. M.
Published: August 2011

Translating observations taken at small spatio-temporal scales into expected patterns at greater scales is a major challenge in spatial ecology because there is typically insufficient relevant information. Here, it is shown that truncated Lévy walks are the most conservative, maximally non-committal description of movement patterns beyond the scale of data collection when correlated random walks characterize observed movements and when there is partial information about landscape and behavioural heterogeneity. This provides a new conceptual basis for Lévy walks that is divorced from optimal searching theory and free from the difficulties with discerning their presence in empirical data.
A nanoscale experiment measuring gravity's role in breaking the unitarity of quantum dynamics
Authors: van Wezel Jasper , Oosterkamp Tjerk H.
Published: August 2011

Modern, state-of-the-art nanomechanical devices are capable of creating spatial superpositions that are massive enough to begin to experimentally access the quantum to classical crossover, and thus force us to consider the possible ways in which the usual quantum dynamics may be affected. One recent theoretical proposal describes the crossover from unitary quantum mechanics to classical dynamics as a form of spontaneous symmetry breaking. Here, we propose a specific experimental set-up capable of identifying the source of unitarity breaking in such a mechanism. The experiment is aimed specifically at clarifying the role played by gravity, and distinguishes the resulting dynamics from that suggested by alternative scenarios for the quantum to classical crossover. We give both a theoretical description of the expected dynamics, and a discussion of the involved experimental parameter values and the proposed experimental protocol.
Positive or negative Poynting effect? The role of adscititious inequalities in hyperelastic materials
Authors: Mihai L. Angela , Goriely Alain
Published: August 2011

Motivated by recent experiments on biopolymer gels whereby the reverse of the usual (positive) Poynting effect was observed, we investigate the effect of the so-called ‘adscititious inequalities’ on the behaviour of hyperelastic materials subject to shear. We first demonstrate that for homogeneous isotropic materials subject to pure shear, the resulting deformation consists of a triaxial stretch combined with a simple shear in the direction of the shear force if and only if the Baker–Ericksen inequalities hold. Then for a cube deformed under pure shear, the positive Poynting effect occurs if the ‘sheared faces spread apart’, whereas the negative Poynting effect is obtained if the ‘sheared faces draw together’. Similarly, under simple shear deformation, the positive Poynting effect is obtained if the ‘sheared faces tend to spread apart’, whereas the negative Poynting effect occurs if the ‘sheared faces tend to draw together’. When the Poynting effect occurs under simple shear, it is reasonable to assume that the same sign Poynting effect is obtained also under pure shear. Since the observation of the negative Poynting effect in semiflexible biopolymers implies that the (stronger) empirical inequalities may not hold, we conclude that these inequalities must not be imposed when such materials are described.
Asexual queen succession in the subterranean termite
Reticulitermes virginicus
Authors: Vargo Edward L. , Labadie Paul E. , Matsuura Kenji
Published: August 2011

Termite colonies are founded by a pair of primary reproductives. In many species, including subterranean termites (family Rhinotermitidae), the primary king and queen can be succeeded by neotenic reproductives that are produced from workers or nymphs within the colony. It is generally believed that these neotenics inbreed within the colony, sometimes for many generations. Here, we show that primary queens of the North American subterranean termite,
Reticulitermes virginicus
, are replaced by numerous parthenogenetically produced female neotenics. We collected functional female neotenics from five colonies of
R. virginicus
in North Carolina and Texas, USA. Genetic analysis at eight microsatellite loci showed that 91–100% of the neotenics present within a colony were homozygous at all loci, indicating that they were produced through automictic parthenogenesis with terminal fusion. In contrast, workers, soldiers and alates were almost exclusively sexually produced by mating between the female neotenics and a single king. This is the second termite species shown to undergo asexual queen succession, a system first described in the Japanese species,
Reticulitermes speratus
. Thus, the conditional use of sexual and asexual reproduction to produce members of different castes may be widespread within
Reticulitermes
and possibly other subterranean termites.
Dietary quality and encephalization in platyrrhine primates
Authors: Allen Kari L. , Kay Richard F.
Published: August 2011

The high energetic costs of building and maintaining large brains are thought to constrain encephalization. The ‘expensive-tissue hypothesis’ (ETH) proposes that primates (especially humans) overcame this constraint through reduction of another metabolically expensive tissue, the gastrointestinal tract. Small guts characterize animals specializing on easily digestible diets. Thus, the hypothesis may be tested via the relationship between brain size and diet quality. Platyrrhine primates present an interesting test case, as they are more variably encephalized than other extant primate clades (excluding Hominoidea). We find a high degree of phylogenetic signal in the data for diet quality, endocranial volume and body size. Controlling for phylogenetic effects, we find no significant correlation between relative diet quality and relative endocranial volume. Thus, diet quality fails to account for differences in platyrrhine encephalization. One taxon, in particular,
Brachyteles
, violates predictions made by ETH in having a large brain and low-quality diet. Dietary reconstructions of stem platyrrhines further indicate that a relatively high-quality diet was probably in place prior to increases in encephalization. Therefore, it is unlikely that a shift in diet quality was a primary constraint release for encephalization in platyrrhines and, by extrapolation, humans.
miR393 and Secondary siRNAs Regulate Expression of the TIR1/AFB2 Auxin Receptor Clade and Auxin-Related Development of Arabidopsis Leaves
Authors: Si-Ammour Azeddine , Windels David , Arn-Bouldoires Estelle , Kutter Claudia , Ailhas Jérôme , Meins Frederick , Vazquez Franck
Published: August 2011

The phytohormone auxin is a key regulator of plant growth and development that exerts its functions through F-box receptors. Arabidopsis (Arabidopsis thaliana) has four partially redundant of these receptors that comprise the TRANSPORT INHIBITOR RESPONSE1/AUXIN SIGNALING F-BOX1 auxin receptor (TAAR) clade. Recent studies have shown that the microRNA miR393 regulates the expression of different sets of TAAR genes following pathogen infection or nitrate treatment. Here we report that miR393 helps regulate auxin-related development of leaves. We found that AtMIR393B is the predominant source for miR393 in all aerial organs and that miR393 down-regulates all four TAAR genes by guiding the cleavage of their mRNAs. A mutant unable to produce miR393 shows developmental abnormalities of leaves and cotyledons reminiscent of enhanced auxin perception by TAARs. Interestingly, miR393 initiates the biogenesis of secondary siRNAs from the transcripts of at least two of the four TAAR genes. Our results indicate that these siRNAs, which we call siTAARs, help regulate the expression of TAAR genes as well as several unrelated genes by guiding the cleavage of their mRNAs. Thus, miR393 and possibly siTAARs regulate auxin perception and certain auxin-related aspects of leaf development.
Age differences in diagnostic criteria of DSM‐IV alcohol dependence among adults with similar drinking behaviour
Authors: Pabst Alexander , Kraus Ludwig , Piontek Daniela , Baumeister Sebastian E.
Published: August 2011

Aims  To test age differences in the prevalence of DSM‐IV alcohol dependence (AD) diagnostic criteria in the adult general population while controlling for drinking behaviour.

Design and setting  Cross‐sectional data from the 2006 German Epidemiological Survey of Substance Abuse (ESA) were used, applying a two‐stage probability sampling design. The survey used self‐administered questionnaires and telephone interviews (mixed‐mode design; 45% response rate).

Participants  The analytical sample consisted of n = 6984 individuals aged 18–64 years reporting alcohol consumption within the previous year.

Measurements  Age effects on individual AD criteria were estimated using logistic regression models, adjusting for eight mutually exclusive drinking groups (defined in terms of average daily alcohol intake and episodic heavy drinking) and socio‐economic variables.

Findings  When controlling for drinking behaviour, 18–24‐year‐olds were more likely to meet the criteria ‘tolerance’, ‘larger/longer’ and ‘time spent’ relative to older age groups. In contrast, the likelihood of experiencing ‘withdrawal’ symptoms increased with age. There was no significant age effect on the diagnosis of AD.

Conclusions  Age differences in the prevalence of specific alcohol dependence diagnostic criteria such as ‘tolerance’, ‘drinking larger amount or for longer than intended’ and ‘time spent recovering’ cannot be fully explained by differences in drinking behaviour.
Personal and environmental pathways to participation in young children with and without mild motor disabilities
Authors: Soref B. , Ratzon N. Z. , Rosenberg L. , Leitner Y. , Jarus T. , Bart O.
Published: August 2011

Objective Participation in everyday activities has a positive influence upon health and well‐being and is considered as an outcome measure. According to recent models child participation is the product of the dynamic interaction between health states and both individual and environmental factors. Children with mild developmental disabilities often present decreased participation in everyday activities. The purpose of this study was to explore the extent to which individual and environmental factors explain the participation of young children, with and without mild motor disabilities.

Methods The study population included 58 kindergarten children together with their parents (29 children with mild motor disabilities who were referred to occupational therapy and 29 children without motor disabilities). Both groups of children were matched for: age; gender; age of parents; and socio‐economic status (SES). We assessed participation using the Child Participation Questionnaire (intensity, diversity, independence, child enjoyment and parental satisfaction) and we assessed children's self‐efficacy and motor abilities for individual factors. Parental self‐efficacy and SES were collected by questionnaires.

Results Participation diversity (number of activities) was predicted by child and mother self‐efficacy and by SES. Child independence and enjoyment as well as parental satisfaction were predicted by child motor ability but mainly by maternal self‐efficacy. Results suggest that the total explained variance is more than double when the environmental variables (parental self‐efficacy and SES) are inserted to the participation model.

Conclusions Maternal self‐efficacy and SES serve as facilitators to increased participation and well‐being of children with mild motor disabilities.
Sex differences in immunity and rapid upregulation of immune defence during parental care in the burying beetle, Nicrophorus orbicollis
Authors: Steiger Sandra , Gershman Susan N. , Pettinger Adam M. , Eggert Anne‐Katrin , Sakaluk Scott K.
Published: August 2011

1. Immunity may trade‐off against other important life history traits, with recent work suggesting that reproduction and parental care in particular impinge on immune defence. However, whereas the effect of parental care on immunocompetence has been intensively studied in birds and mammals, virtually nothing is known about how it affects insect immunity.

2. Burying beetles provide extensive biparental care that includes the burial, preparation and defence of a carcass, as well as the subsequent feeding of the larvae. In addition, they cover the carcass with anal exudates that have been shown to serve an antimicrobial function (social immunity sensu Behavioral Ecology, 21, 663–668). We examined the effect of sex, mating and parental care on measurements of individual and social immunity in the burying beetle Nicrophorus orbicollis.

3. Both males and females showed a rapid upregulation of the encapsulation response upon discovery of a carcass. The high encapsulation rate was maintained during the entire period of parental care. Lytic activity in anal exudates, a measure of social immunity, likewise increased. Mating had no effect on individual or social immunity, but females generally exhibited higher individual immunity than male N. orbicollis.

4. Our results suggest that the unusual breeding environment of burying beetles – a microbe‐rich carcass – has selected for an atypical pattern of immune defence, with a significant upregulation of individual and social immunity during the physically demanding period of reproduction and parental care. The simultaneous investment in two life history traits that normally compete for resources may be an adaptive response in species that breed in environments with high densities of micro‐organisms.
A qualitative study exploring the emotional responses of female patients learning to perform clean intermittent self‐catheterisation
Authors: Ramm Dianne , Kane Ros
Published: August 2011

Aim.  This paper is a report of a study exploring the lived experiences and emotional responses of female patients learning to perform clean intermittent self‐catheterisation (CISC).

Background.  There is general consensus that CISC should be considered in preference to in‐dwelling catheterisation wherever feasible. Published literature has tended to focus on quality of life issues and technical and physical aspects. There has been less investigation into patients’ initial perceptions of CISC and into their subsequent experiences of learning the technique.

Design.  This qualitative study used a phenomenological research design.

Method.  A series of semi‐structured, in‐depth interviews were held with a purposive sample of adult female patients performing CISC aged 34–64 years. Interviews were tape recorded and transcribed verbatim. Data were analysed using the ‘Framework’ method.

Results.  This study identified six recurrent themes: grief and loss, lack of knowledge (regarding female anatomy, bladder dysfunction and catheters), negative associations and stigma, psychological aversion and embarrassment, nursing approaches and coping mechanisms.

Conclusion.  Loss of normal bladder function may represent a devastating event and trigger emotional responses associated with grief and loss. Patients may experience a range of reactions whilst learning CISC, including embarrassment and aversion, which may not dissipate over time. However, psychological distress is not inevitable and varies enormously between individuals. The nursing approach is vital, as individualised, empathic care is recognised and valued.

Relevance to clinical practice.  This study adds to an emerging body of knowledge providing an enhanced understanding of the lived experiences of patients learning CISC. Nurses need to be alert to a range of potential emotional responses. This will facilitate the adoption of individualised teaching and learning strategies, designed to optimise the patient’s assimilation of CISC into their lifestyle, promoting physical health, psychological wellbeing and independent living.
Periodic leg movements during sleep in narcoleptic patients with or without restless legs syndrome
Authors: PLAZZI GIUSEPPE , FERRI RAFFAELE , FRANCESCHINI CHRISTIAN , VANDI STEFANO , DETTO STEFANIA , PIZZA FABIO , POLI FRANCESCA , DE COCK VALÉRIE C. , BAYARD SOPHIE , DAUVILLIERS YVES
Published: August 2011

We compared periodic and non‐periodic leg movements during sleep and polysomnography in patients with narcolepsy with cataplexy (NC) with or without restless legs syndrome (RLS) with matched idiopathic RLS (iRLS) and control subjects. We enrolled 100 patients with NC: 17 having RLS were compared with 34 sex‐ and age‐matched patients without RLS and with 17 normal controls and 17 iRLS subjects. Periodic leg movements were highest in iRLS and lowest in controls, with those in NC with RLS very close to iRLS, but higher than those in NC without RLS. The periodicity indexes showed the highest value in iRLS followed by NC with or without RLS and, finally, by controls. The inter‐leg movement intervals peaked between 10 and 50 s in NC with RLS and in iRLS, the former did not display the nocturnal gradual decrease of periodic leg movements typical of iRLS. Periodic leg movements during sleep and polysomnography displayed specific features in RLS and NC, respectively, with NC with RLS showing an intermediate pattern. Even if RLS is only detected by targeted interview in NC, its frequency and impact on night‐time sleep architecture and continuity suggest that this condition should be routinely searched for in NC.
An EAR‐motif‐containing ERF transcription factor affects herbivore‐induced signaling, defense and resistance in rice
Authors: Lu Jing , Ju Hongping , Zhou Guoxin , Zhu Chuanshu , Erb Matthias , Wang Xiaopeng , Wang Peng , Lou Yonggen
Published: August 2011

Ethylene responsive factors (ERFs) are a large family of plant‐specific transcription factors that are involved in the regulation of plant development and stress responses. However, little to nothing is known about their role in herbivore‐induced defense. We discovered a nucleus‐localized ERF gene in rice (Oryza sativa), OsERF3, that was rapidly up‐regulated in response to feeding by the rice striped stem borer (SSB) Chilo suppressalis. Antisense and over‐expression of OsERF3 revealed that it positively affects transcript levels of two mitogen‐activated protein kinases (MAPKs) and two WRKY genes as well as concentrations of jasmonate (JA), salicylate (SA) and the activity of trypsin protease inhibitors (TrypPIs). OsERF3 was also found to mediate the resistance of rice to SSB. On the other hand, OsERF3 was slightly suppressed by the rice brown planthopper (BPH) Nilaparvata lugens (Stål) and increased susceptibility to this piercing sucking insect, possibly by suppressing H2O2 biosynthesis. We propose that OsERF3 affects early components of herbivore‐induced defense responses by suppressing MAPK repressors and modulating JA, SA, ethylene and H2O2 pathways as well as plant resistance. Our results also illustrate that OsERF3 acts as a central switch that gears the plant’s metabolism towards an appropriate response to chewing or piercing/sucking insects.
Phylogenetic and phenotypic originality and abundance in a cerrado plant community
Authors: DA SILVA DANILO MUNIZ , SILVA IGOR AURÉLIO , BATALHA MARCO ANTÔNIO
Published: August 2011

The originality of a species is how much that species contributes to the rarity of traits in a community. Here we tested the relation between abundance and both phylogenetic and phenotypic originality. We measured nine traits associated with defence against herbivory, as well as phylogenetic information and abundance for woody plant species in a woodland cerrado in southeastern Brazil. About 90% of the species accounted for about 50% of the phylogenetic and phenotypic originality: most woody species had low originality. Abundance was related to tougher leaves, lower specific leaf area and lower originality based on nutritional quality. Our results suggest that herbivory may reduce the abundance of species with low resistance to herbivory and with different nutritional quality. Nevertheless, abundance was not related to either phylogenetic or phenotypic originality, so extinction of rare species may not endanger overall community function as long as more abundant species are retained. We argue that this is a consequence of the low complementarity of a large number of woody species.
Size delays female senescence in a medium sized marsupial: The effects of maternal traits on annual fecundity in the northern brown bandicoot (Isoodon macrourus)
Authors: PRICE‐REES SAMANTHA J. , CONGDON BRADLEY C. , KROCKENBERGER ANDREW K.
Published: August 2011

The degree to which females allocate resources between current reproduction, future fecundity and survival is a central theme in life history theory. We investigated two hypotheses proposed to explain patterns of reproductive investment, terminal investment and senescence, by examining the effects of maternal traits (age and maternal mass) on annual fecundity in female northern brown bandicoots, Isoodon macrourus (Marsupialia: Peramelidae). We found that annual fecundity in females declined in their final year of reproduction, indicating reproductive senescence. Maternal mass significantly influenced the rate of senescence and, in turn, a female's lifetime reproductive output. Mass had little effect on fecundity in 1st and 2nd year females, but a positive relationship with fecundity in 3rd year females. This meant that heavy, 3rd year females did not suffer the decline in fecundity shown in light 3rd year females. For 1st year females, mass and leg length increased between their first and second reproductive seasons, indicating a temporary shift, from the allocation of resources to reproduction, to increasing condition or structural size post their first breeding event. There were no net changes to body mass in subsequent years. We suggest that this year of post‐reproductive growth has important consequences for senescent effects on reproduction. Overall, results provided support for the effects of senescence on annual fecundity. Our findings were not consistent with the terminal investment hypothesis; reproductive output did not increase in females' final reproductive season despite a rapid decline in survival. However, this notion cannot be entirely dismissed; other measures of reproductive performance not examined here (e.g. offspring mass) may have provided an indication that females did increase their effort at the end of their lifespan. This study highlights the difficulty of measuring reproductive costs and the importance of understanding the combined effects of specific characteristics of an individual when interpreting reproductive strategies in iteroparous organisms.
Foraging conditions ‘at the end of the world’ in the context of long‐distance migration and population declines in red knots
Authors: ESCUDERO GRACIELA , NAVEDO JUAN G. , PIERSMA THEUNIS , DE GOEIJ PETRA , EDELAAR PIM
Published: August 2011

The long‐distance migrant red knot (Calidris canutus ssp. rufa– Scolopacidae) alternates between the northern and southern ends of the New World, one of the longest yearly migrations of any bird and paradoxically overflying apparently suitable habitat at lower latitudes. This subspecies is sharply declining, with a major mortality event following 2000, attributed to commercial overharvesting of food resources at its Delaware Bay (USA) stop‐over site. A full understanding of this peculiar migrant requires an assessment of the foraging conditions at its southern hemisphere wintering sites. Here, for a major wintering site in Argentinean Tierra del Fuego (Río Grande), we describe and compare food abundance, diet and intake rates during January–February in 1995, 2000 and 2008. The two main prey types were the burrowing clam Darina solenoides and three species of epibenthic mussels Mytilidae. In the year 2000, food availability and intake rate were higher than those recorded at other sites used by knots anywhere else in the world, contributing to the explanation of why red knots carry out this impressive migration. Intake rate in 2008 on the two main prey types was dramatically reduced as a result of birds eating smaller prey and strongly increased human disturbance; the same year we also found a high prevalence of a digenean parasite in Darina. We suggest that during the strongly enhanced winter mortality in 2000, knots did not yet face ecological problems in their southernmost wintering area, consistent with the previous evidence that problems at northern stop‐overs negatively affected their numbers. However, in 2008 the ecological conditions at Río Grande were such that they would have facilitated a further decline, emphasizing the importance of a hemispheric approach to research and management.
Non‐bacterial thrombotic endocarditis with systemic embolic events caused by adenomyosis
Authors: Soeda Shu , Mathuda Nozomi , Hashimoto Yuko , Yamada Hidekazu , Fujimori Keiya
Published: August 2011

Non‐bacterial thrombotic endocarditis is caused by a hypercoagulable state that is sometimes related to malignancy and this type of endocarditis associated with benign tumors has not yet been reported. In this study we report the first case of non‐bacterial thrombotic endocarditis caused by adenomyosis, which is a benign gynecological condition.