bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence‐Based Surgery: Barriers, Solutions, and the Role of Evidence Synthesis
Authors: Garas George , Ibrahim Amel , Ashrafian Hutan , Ahmed Kamran , Patel Vanash , Okabayashi Koji , Skapinakis Petros , Darzi Ara , Athanasiou Thanos
Published: April 2012

Background

Surgery is a rapidly evolving field, making the rigorous testing of emerging innovations vital. However, most surgical research fails to employ randomized controlled trials (RCTs) and has particularly been based on low‐quality study designs. Subsequently, the analysis of data through meta‐analysis and evidence synthesis is particularly difficult.

Methods

Through a systematic review of the literature, this article explores the barriers to achieving a strong evidence base in surgery and offers potential solutions to overcome the barriers.

Results

Many barriers exist to evidence‐based surgical research. They include enabling factors, such as funding, time, infrastructure, patient preference, ethical issues, and additionally barriers associated with specific attributes related to researchers, methodologies, or interventions. Novel evidence synthesis techniques in surgery are discussed, including graphics synthesis, treatment networks, and network meta‐analyses that help overcome many of the limitations associated with existing techniques. They offer the opportunity to assess gaps and quantitatively present inconsistencies within the existing evidence of RCTs.

Conclusions

Poorly or inadequately performed RCTs and meta‐analyses can give rise to incorrect results and thus fail to inform clinical practice or revise policy. The above barriers can be overcome by providing academic leadership and good organizational support to ensure that adequate personnel, resources, and funding are allocated to the researcher. Training in research methodology and data interpretation can ensure that trials are conducted correctly and evidence is adequately synthesized and disseminated. The ultimate goal of overcoming the barriers to evidence‐based surgery includes the improved quality of patient care in addition to enhanced patient outcomes.
Metal biosorption in lignocellulosic biofuel biorefinery effluent: an initial step towards sustainability of water resources
Authors: Palumbo Amanda J , Taylor Sean C , Addison Sarah L , Slade Alison H , Glover Chris N
Published: April 2012

Biosorption of metals by microorganisms is a promising technology to remove accumulated non-process elements in highly recycled biorefinery process water. Removal of these elements would enable greater water reuse and reduce the environmental impact of effluent discharge. A model lignocellulosic ethanol biorefinery wastewater was created based on pulp mill effluent. This generated a wastewater with an environmentally realistic high loading of dissolved natural organic matter (900 mg/l), a potentially important factor influencing metal biosorption. Analysis of feedstock and pulp mill effluent indicated that Mn and Zn are likely to be problematic in highly recycled lignocellulosic ethanol biorefinery process water. Therefore, the growth of several bacteria and fungi from existing collections, and some isolated from pulp mill effluent were tested in the model wastewater spiked with Mn and Zn (0.2 mM). Wastewater isolates grew the best in the wastewater. Metal uptake varied by species and was much greater for Zn than Mn. A bacterium, Novosphingobium nitrogenifigens Y88T, removed the most metal per unit biomass, 35 and 17 mg Mn/g. No other organism tested decreased the Mn concentration. A yeast, Candida tropicalis, produced the most biomass and removed the most total metal (38 % of Zn), while uptake per unit biomass was 24 mg Zn/g. These results indicate that microorganisms can remove significant amounts of metals in wastewater with high concentrations of dissolved natural organic matter. Metal sorption by autochthonous microorganisms in an anaerobic bioreactor may be able to extend water reuse and therefore lower the water consumption of future biorefineries.
Analysis of vertical stratification of Syrphidae (Diptera) in an oak‐hornbeam forest in northern Italy
Authors: Birtele Daniele , Hardersen Sönke
Published: April 2012

There is growing interest in the vertical stratification of forest biodiversity, but little is known about this aspect for Syrphidae living in forests. For this study, seven Malaise traps were suspended in the canopy and seven were placed on the ground, in a lowland forest in northern Italy. Altogether, 868 specimens of Syrphidae were collected; 229 from the canopy and 639 from the ground, comprising a total of 53 species. Three species [(Ceriana conopsoides (Linnaeus), Eupeodes corollae (Fabricius), Psilota atra Fallén)] were associated significantly with the canopy layer, and seven species [(Brachypalpoides lentus (Meigen), Chalcosyrphus nemorum (Fabricius), Chrysotoxum cautum (Harris), Eumerus flavitarsis Zetterstedt, Helophilus pendulus (Linnaeus), Myathropa florea (Linnaeus) and Xylota segnis (Linnaeus)] with the ground level. The sex‐ratio of the Syrphidae differed significantly between the two layers, as females were caught mainly at ground level, while males were caught preferentially in the canopy. Species with saprophagous and saproxylic larvae were caught more commonly at ground level. Species richness declined from April to November but vertical stratification was constant for most of the season. Multivariate analyses showed that two factors were correlated significantly with the community composition of Syrphidae: height of Malaise trap and estimated age of dominant trees.
Unilateral varus osteotomy of the proximal femur in children with cerebral palsy: A five-year follow-up of the development of both hips
Authors: Larsson Maria , Hägglund Gunnar , Wagner Philippe
Published: April 2012

Background

Varus osteotomy of the proximal femur (VOPF) is one treatment option to prevent hip dislocation in children with cerebral palsy (CP). It is questioned whether the osteotomy should be performed in the displaced hip only, or if it should be performed bilaterally to prevent later displacement of the contralateral hip. CPUP is a register and healthcare programme for children with CP that was initiated in 1994 in southern Sweden. In the programme, range-of-motion and radiographic examination of the hips is performed regularly. These data have been analysed preoperatively and for 5 years postoperatively in children treated with unilateral VOPF.

Methods

Children with CP living in the counties of Skåne and Blekinge in the south of Sweden, who were treated with unilateral VOPF at least 5 years ago, were included in the study. The degree of hip displacement and the range of hip motion were analysed preoperatively and after 5 years. Repeat hip operations after the index operation were recorded.

Results

Twenty-four children fulfilled the inclusion criteria. Mean age at index operation was 7.6 (2.8–13.2) years. No child died within 5 years postoperatively, and no child was lost from follow-up. At follow-up after 5 years, 2 of the 24 children had been operated on with VOPF in the contralateral hip. The range of motion in both hips decreased, but the difference between the index hip and the contralateral hip did not change significantly.

Conclusion

Children with CP and unilateral hip displacement have a low risk of later contralateral displacement after being operated on with unilateral VOPF. This supports healthcare programmes that advocate unilateral VOPF in children with unilateral hip displacement.
Recovery of Functional Status After Stroke in a Tri‐Ethnic Population
Authors: Berges Ivonne‐M. , Kuo Yong‐Fang , Ottenbacher Kenneth J. , Seale Gary S. , Ostir Glenn V.
Published: April 2012

Objective

To examine recovery of functional status for white, black, and Hispanic patients who have had a stroke from the time of admission to inpatient medical rehabilitation to 12 months after discharge.

Design

A longitudinal study that used information from the Stroke Recovery in Underserved Population database, a prospective observational study of persons with stroke who received inpatient medical rehabilitation services during 2005‐2006.

Setting

Eleven inpatient rehabilitation facilities located across diverse regions of the United States, including California, Florida, Iowa, Illinois, Kentucky, New Jersey, New York (2), Texas (2), and Washington, DC.

Participants

A total of 990 adults aged 55 years or older who had a stroke and were admitted to 1 of 11 inpatient medical rehabilitation facilities in the United States were interviewed at 4 time points, including admission to and discharge from an inpatient medical rehabilitation facility and 3 and 12 months after discharge.

Interventions

Not applicable.

Main Outcome Measure

Functional status as measured by the Functional Independence Measure (FIM).

Results

For the total sample, FIM ratings increased from admission to discharge and from discharge to 3‐month follow‐up, with little recovery occurring between 3 and 12 months. In random effects mixed models, at 3‐month follow‐up, both black and Hispanic patients had lower FIM ratings than did white patients. At 12‐month follow‐up, black and white patients were similar; however, Hispanic patients continued to have lower FIM ratings compare with white patients. Racial/ethnic group, age, length of stay, and medical comorbidities were significant predictors of total FIM ratings over the 4 time points.

Conclusions

Persons 55 years and older who have had a stroke, regardless of race/ethnicity, appear to benefit from inpatient medical rehabilitation. Most functional status gains occur during inpatient medical rehabilitation and continue in the first few months after discharge, with little change afterward.
Densities of the Vulnerable marsh deer Blastocerus dichotomus in Bolivia's northern savannahs
Authors: Ríos-Uzeda Boris , Mourão Guilherme
Published: April 2012

Aerial surveys have been used successfully to estimate vertebrate populations in open habitats. The marsh deer Blastocerus dichotomus, categorized as Vulnerable on the IUCN Red List, lives in such habitats and is suitable for aerial counting because it is conspicuous. This species, the largest South American deer, is native to Argentina, Boliva, Brazil, Paraguay and Peru but no reliable information has previously been available on its populations in Bolivia. From May to August 2007 we conducted aerial transects to survey marsh deer in three large areas of savannah. We used a modified mark–recapture method to improve the accuracy of the counts and estimated density and abundance. The corrected, estimated density of the marsh deer was 0.24 km−2 in the northern La Paz Department, 0.12 km−2 in Mamoré and 0.15 km−2 in Iténez. These densities are similar to the mean density of the species on other South American savannahs. This is the first large-scale survey of the marsh deer in Bolivia and the first to provide information about the density of the species in the Amazon. We recommend the creation of protected areas in these savannahs, and wildlife and domestic health programmes to conserve the marsh deer of this region.
Integrating family planning service provision into community-based marine conservation
Authors: Harris Alasdair , Mohan Vik , Flanagan Maggie , Hill Rebecca
Published: April 2012

Human population growth is one of the primary drivers of biodiversity loss. Throughout much of the developing world growth of human populations is occurring in part as a result of a lack of access to sexual and reproductive health services, and this is having profoundly negative impacts on biodiversity and natural resource-dependent livelihoods. We present experiences of the incorporation of sexual and reproductive health services within a pre-existing community-based marine conservation initiative in Madagascar as part of an integrated population, health and environment (PHE) programme. Our results demonstrate the considerable demand for, and lack of social barriers to, the introduction of sexual and reproductive health services in this region. These findings emphasize the mutually beneficial synergies, supporting both public health and conservation objectives, which can be created by integrating sexual and reproductive health services into more conventional biodiversity conservation activities. This PHE approach demonstrates the inextricable link between reproductive health and resource use by providing practical, immediate and lasting benefits to public health, gender equity, food security and biodiversity conservation.
Mixed choruses and marriage songs: a new interpretation of the third stasimon of the Hippolytos
Authors: Swift L.A.
Published: April 2012

This article uses evidence drawn from hymenaios and wedding ritual to reach a new interpretation of the third stasimon of the Hippolytos, and its rôle in the play. There is longstanding contention about whether a second (male) chorus participates in the ode, singing in antiphony with the existing tragic chorus. Even scholars who accept that a second chorus is present have tended to regard it as an aberration which needs to be explained away, rather than a deliberate choice with poetic significance. I discuss the cultural implications of such a chorus, examining our evidence for real-life mixed choruses, and then applying this to the ode itself. The evidence for mixed choruses suggests they are strongly associated with marriage. Looking more closely at the language and imagery of the ode, there are allusions to the topoi of wedding songs and ritual running through it. The ode can use these as a device to trigger deep-rooted responses and associations from the audience, as these motifs are drawn from the cultural tradition which the audience shares. The topoi tie in with the theme of marriage and sexuality within the Hippolytos as a whole. But while their usual purpose is to set up conventional models and ways of thinking, the way they are deployed in the ode in fact serves to undermine these models, and to put a darker spin on the norms of sexual behaviour. This strand of imagery therefore also provides a filter for interpreting Hippolytos' own attitude towards sexuality, and a guide to how we are meant to respond to it.
Why Even Morally Perfect People Would Need Government
Authors: Kavka Gregory S.
Published: April 2012

Why do we need government? A common view is that government is necessary to constrain people's conduct toward one another, because people are not sufficiently virtuous to exercise the requisite degree of control on their own. This view was expressed perspicuously, and artfully, by liberal thinker James Madison, in The Federalist, number 51, where he wrote: “If men were angels, no government would be necessary.” Madison's idea is shared by writers ranging across the political spectrum. It finds clear expression in the Marxist view that the state will gradually wither away after a communist revolution, as unalienated “communist man” emerges. And it is implied by the libertarian view that government's only legitimate function is to control the unfortunate and immoral tendency of some individuals to violate the moral rights of others.
Coexistence of three calcium carbonate polymorphs in the shell of the Antarctic clam Laternula elliptica
Authors: Nehrke Gernot , Poigner Harald , Wilhelms‐Dick Dorothee , Brey Thomas , Abele Doris
Published: April 2012

We analyzed shell cuts of five individuals of the Antarctic bivalve Laternula elliptica from three locations along the Antarctic Peninsula by means of Confocal Raman Microscopy (CRM) as well as Electron Microprobe (EMP). The shell of L. elliptica has been previously described as being composed of aragonite exclusively. Now, CRM mapping reveals that three polymorphs of calcium carbonate – aragonite, calcite, and vaterite – are present in the chondrophore region of the examined individuals. Annual shell growth layers continue through aragonite and vaterite, suggesting simultaneous mineralization of both polymorphs. Spatially congruent EMP scans showed that the calcium carbonate polymorph affects the distribution of magnesium and strontium within the chondrophore. This is, to our knowledge, the first report of the coexistence of these three calcium carbonate polymorphs within the mineralized structures of a marine calcifying organism. Particularly the presence of vaterite is unexpected, but shows striking similarities to some fish otoliths. The strong effect of the calcium carbonate polymorph on trace element incorporation restrict the suitability of magnesium and strontium based proxies for the chondrophore area of L. elliptica.
Bayesian prediction of geomagnetic storms: Wind data, 1996–2010
Authors: Chen James , Slinker Steven P. , Triandaf Ioana
Published: April 2012

The feature‐based Bayesian method previously developed by Chen et al. (1996, 1997) to predict the occurrence, severity, and duration of large geomagnetic storms has been run on a daily basis on the Wind/Magnetic Fields Investigation (MFI) data from January 1996 until March 2010. The algorithm uses as input real‐time solar wind magnetic field data obtained at the L1 Lagrange point, and the output is the probability prediction of the magnetic field structure of the upstream solar wind that has yet to arrive, and its geoeffectiveness, where geoeffectiveness is measured by the traditional Dst index. The performance characteristics of the method are evaluated using a four‐level contingency table: nonstorm disturbances (−80 nT < Dst ≤ − 50 nT), weak storms (−120 nT < Dst ≤ − 80 nT), moderate storms (−160 nT < Dst ≤ − 120 nT), and strong storms (Dst ≤ − 160 nT). It is found that the greater the level of disturbances, the more accurate the prediction is. With moderate and strong storms combined, the algorithm correctly predicted 30 out of 37 storms (81%). The false negatives are caused by solar wind structures with short durations (≲ 1–2 hrs) of strong southward magnetic field (say, Bz ≲ −30 nT), which are sparsely represented in the probability distribution functions constructed using prior solar wind data (OMNI data set from 1973–1981). The algorithm does not predict the storm onset time, but the results of the present and previous tests show that the average warning time ranges from a few hours to a maximum of 10–15 hours.
Ferromagnetic resonance characterization of greigite (Fe3S4), monoclinic pyrrhotite (Fe7S8), and non‐interacting titanomagnetite (Fe3‐xTixO4)
Authors: Chang Liao , Winklhofer Michael , Roberts Andrew P. , Dekkers Mark J. , Horng Chorng‐Shern , Hu Lei , Chen Qianwang
Published: April 2012

Ferromagnetic resonance (FMR) spectroscopy has become an increasingly useful tool for studying the magnetic properties of natural samples. Magnetite (Fe3O4) is the only magnetic mineral that has been well characterized using FMR. This limits the wider use of FMR in rock magnetism and paleomagnetism. In this study, we applied FMR analysis to a range of magnetic minerals, including greigite (Fe3S4), monoclinic pyrrhotite (Fe7S8), magnetically non‐interacting titanomagnetite (Fe3‐xTixO4), and synthetic magnetite chains to constrain interpretation of FMR analysis of natural samples and to explore applications of FMR spectroscopy. We measured the FMR signatures of a wide range of well‐characterized samples at the X‐ and Q‐bands. FMR spectra were also simulated numerically to compare with experimental results. The effects of magnetic anisotropy, mineralogy, domain state, and magnetostatic interactions on the FMR spectra are discussed for all studied minerals. Our experimental and theoretical analyses of magnetically non‐interacting tuff samples and magnetically interacting chains enable quantitative assessment of contributions of magnetostatic interactions and magnetic anisotropy to the FMR spectra. Our results also indicate that intact magnetosomes are a unique system with distinct FMR signatures. While FMR analysis is useful for characterizing magnetic properties of natural samples, care is needed when making interpretations because of overlaps in a range of FMR signatures of different magnetic minerals with different magnetic properties. Our analyses will help to constrain such interpretations in rock magnetic studies.
Reaction cross sections for two direct simulation Monte Carlo models: Accuracy and sensitivity analysis
Authors: Wysong Ingrid , Gimelshein Sergey , Gimelshein Natalia , McKeon William , Esposito Fabrizio
Published: April 2012

The quantum kinetic chemical reaction model proposed by Bird for the direct simulation Monte Carlo method is based on collision kinetics with no assumed Arrhenius-related parameters. It demonstrates an excellent agreement with the best estimates for thermal reaction rates coefficients and with two-temperature nonequilibrium rate coefficients for high-temperature air reactions. This paper investigates this model further, concentrating on the non-thermal reaction cross sections as a function of collision energy, and compares its predictions with those of the earlier total collision energy model, also by Bird, as well as with available quasi-classical trajectory cross section predictions (this paper also publishes for the first time a table of these computed reaction cross sections). A rarefied hypersonic flow over a cylinder is used to examine the sensitivity of the number of exchange reactions to the differences in the two models under a strongly nonequilibrium velocity distribution.
Formation and structure of colloidal halos in two-dimensional suspensions of paramagnetic particles
Authors: Viveros-Méndez P. X. , Méndez-Alcaraz J. M. , González-Mozuelos P.
Published: April 2012

Different Monte Carlo simulation approaches are used here to study the static structure induced by a spherical neutral substrate inserted in the midst of a two-dimensional suspension of paramagnetic particles. It is then observed that in some instances some of these particles are adsorbed to the surface of the substrate, forming colloidal halos. We investigate the necessary conditions for the formation of these halos and the dependence of the number of adsorbed particles on the relevant parameters of the system. The angular distribution of the adsorbed particles around the perimeter of the substrate is analyzed here too.
A low-voltage high-speed electronic switch based on piezoelectric transduction
Authors: Newns Dennis , Elmegreen Bruce , Hu Liu Xiao , Martyna Glenn
Published: April 2012

We propose a novel digital switch, the piezoelectronic transistor or PET. Based on properties of known materials, we predict that a nanometer-scale PET can operate at low voltages and relatively high speeds, exceeding the capabilities of any conventional field effect transistor (FET). Depending on the degree to which these attributes can be simultaneously achieved, the device has a broad array of potential applications in digital logic. The PET is a 3-terminal switch in which a gate voltage is applied to a piezoelectric (PE), resulting in expansion compressing a piezoresistive (PR) material comprising the channel, which then undergoes a continuous, reversible insulator-metal transition. The channel becomes conducting in response to the gate voltage. A high piezoelectric coefficient PE, e.g., a relaxor piezoelectric, leads to low voltage operation. Suitable channel materials manifesting a pressure-induced metal-insulator transition can be found amongst rare earth chalcogenides, transition metal oxides, and among others. Mechanical requirements include a high PE/PR area ratio to step up pressure, a rigid surround material to constrain the PE and PR external boundaries normal to the strain axis, and a void space to enable free motion of the component side walls. Using static mechanical modeling and dynamic electro-acoustic simulations, we optimize device structure and materials and predict performance.
Generalized complexity measures and chaotic maps
Authors: Godó B. , Nagy Á.
Published: April 2012

The logistic and Tinkerbell maps are studied with the recently introduced generalized complexity measure. The generalized complexity detects periodic windows. Moreover, it recognizes the intersection of periodic branches of the bifurcation diagram. It also reflects the fractal character of the chaotic dynamics. There are cases where the complexity plot shows changes that cannot be seen in the bifurcation diagram.
Negative electron mobility in diamond
Authors: Isberg J. , Gabrysch M. , Majdi S. , Twitchen D. J.
Published: April 2012

By measuring the drift velocity of electrons in diamond as a function of applied electric field, we demonstrate that ultra-pure diamond exhibits negative differential electron mobility in the [100] direction below 140 K. Negative electron mobility is normally associated with III–V or II–VI semiconductors with an energy difference between different conduction band valleys. The observation of negative mobility in diamond, an elemental group IV semiconductor, is explained in terms of repopulation effects between different equivalent conduction band valleys using a model based on the Boltzmann equation.
Hybrid-orientation Ge-on-insulator structures on (100) Si platform by Si micro-seed formation combined with rapid-melting growth
Authors: Kurosawa Masashi , Kawabata Naoyuki , Sadoh Taizoh , Miyao Masanobu
Published: April 2012

Hybrid-integration of (111), (110), and (100) Ge-on-insulator (GOI) on an Si chip is essential to merge III-V semiconductor optical-devices as well as high-speed Ge transistors onto Si-large-scale integrated-circuits. We clarify important-parameters to control Ni-metal-induced lateral crystallization and Al-induced layer-exchange crystallization. This achieves artificial (110) and (111) Si micro-seed on insulating-film. Together with Si substrate as (100) Si seed, multi-crystal-seeds with different orientations are aligned on a Si chip. Then, SiGe-mixing triggered rapid-melting-growth of amorphous-Ge is examined from these multi-crystal-seeds. This enables simultaneous Ge lateral-crystallization with (111), (110), and (100) orientations. High-quality, hybrid-orientation GOIs without defects are demonstrated on Si platform.
Spatial distribution of structural degradation under high-power stress in AlGaN/GaN high electron mobility transistors
Authors: Li Libing , Joh Jungwoo , del Alamo J. A. , Thompson Carl V.
Published: April 2012

The two-dimensional spatial distribution of structural degradation of AlGaN/GaN high electron mobility transistors was investigated under high-power electrical stressing using atomic force and scanning electron microscopy. It was found that pits form on the surface of the GaN cap layer at the edges of the gate fingers in the middle of the device. The average pit area and density increase gradually from the edge to the center of the fingers and are more common along inner fingers than fingers. It was also found that pit formation and growth are thermally activated.
Planar PbS quantum dot/C60 heterojunction photovoltaic devices with 5.2% power conversion efficiency
Authors: Klem E. J. D. , Gregory C. W. , Cunningham G. B. , Hall S. , Temple D. S. , Lewis J. S.
Published: April 2012

Of interest for both photovoltaic and photodetector applications is the ability of colloidal quantum dot (CQD) devices to provide response further into the infrared than is typical for other solution-processable materials. Here, we present a simple heterojunction diode structure that utilizes the extended infrared absorption of PbS CQDs. We show that device performance benefits from a discontinuous exciton blocking layer which improves charge separation without limiting charge extraction. By enhancing charge carrier mobility in the CQD layer, we demonstrate a planar heterostructure device with a power conversion efficiency of 5.2% under 1 sun illumination.
Influence of the dynamic plasma screening on the Ramsauer phenomena for the polarization collision in thermal plasmas
Authors: Ki Dae-Han , Jung Young-Dae
Published: April 2012

The dynamic plasma screening effects on the Ramsauer phenomena for the electron-atom polarization collision are investigated in dense plasmas. The phase theory and the effective Buckingham potential with the dynamic Debye length are employed to obtain the phase shift and total collision cross section as functions of the collision energy, and Debye length, polarizability, scattering length, and thermal energy. The result shows that the energy for the Ramsauer minimum increases with an increase of the thermal energy. It is also found that the dynamic plasma screening effect suppresses the total polarization cross section below the Ramsauer energy. However, it is found that the dynamic plasma screening effect enhances the total polarization cross section above the Ramsauer energy. The screening effect on the Ramsauer energy is also discussed.
Lithium-ion conducting La2/3−xLi3xTiO3 solid electrolyte thin films with stepped and terraced surfaces
Authors: Ohta Hiromichi , Mizoguchi Teruyasu , Aoki Noriyuki , Yamamoto Takashi , Sabarudin Akhmad , Umemura Tomonari
Published: April 2012

La2/3−xLi3xTiO3 (LLT, x = 0.1 and 0.167) thin films were grown on (001)-oriented SrTiO3 (STO) substrates by pulsed laser deposition. The resultant LLT films were heteroepitaxially grown with atomically flat surfaces. Although the films considered to be single crystalline, they were composed of 90°-rotated multi domains (∼5 nm in size) with epitaxial relationships of (100) [001] LLT || (001) [100] STO and (100) [010] LLT || (001) [100] STO. The bulk conductivity of the LLT (x = 0.1) films was 2.5 × 10−2 S cm−1 at 190 °C, comparable to that of a bulk single crystalline LLT. Single crystalline LLT thin films with atomically flat surfaces should help clarify interfacial lithium-ion conductivity.

At the request of the authors, this article is being retracted effective 1 March 2013.
The Role of Head Movements and Signal Spectrum in an Auditory Front/Back Illusion
Authors: Brimijoin W Owen , Akeroyd Michael A
Published: April 2012

We used a dynamic auditory spatial illusion to investigate the role of self-motion and acoustics in shaping our spatial percept of the environment. Using motion capture, we smoothly moved a sound source around listeners as a function of their own head movements. A lowpass filtered sound behind a listener that moved in the direction it would have moved if it had been located in the front was perceived as statically located in front. The contrariwise effect occurred if the sound was in front but moved as if it were behind. The illusion was strongest for sounds lowpass filtered at 500 Hz and weakened as a function of increasing lowpass cutoff frequency. The signals with the most high frequency energy were often associated with an unstable location percept that flickered from front to back as self-motion cues and spectral cues for location came into conflict with one another.
A scissor blade-like closing mechanism implicated in transmembrane signaling in a
Bacteroides
hybrid two-component system
Authors: Lowe Elisabeth C. , Baslé Arnaud , Czjzek Mirjam , Firbank Susan J. , Bolam David N.
Published: April 2012

Signaling across the membrane in response to extracellular stimuli is essential for survival of all cells. In bacteria, responses to environmental changes are predominantly mediated by two-component systems, which are typically composed of a membrane-spanning sensor histidine kinase and a cytoplasmic response regulator. In the human gut symbiont
Bacteroides thetaiotaomicron
, hybrid two-component systems are a key part of the bacterium’s ability to sense and degrade complex carbohydrates in the gut. Here, we identify the activating ligand of the hybrid two-component system, BT4663, which controls heparin and heparan sulfate acquisition and degradation in this prominent gut microbe, and report the crystal structure of the extracellular sensor domain in both apo and ligand-bound forms. Current models for signal transduction across the membrane involve either a piston-like or rotational displacement of the transmembrane helices to modulate activity of the linked cytoplasmic kinases. The structures of the BT4663 sensor domain reveal a significant conformational change in the homodimer on ligand binding, which results in a scissor-like closing of the C-termini of each protomer. We propose this movement activates the attached intracellular kinase domains and represents an allosteric mechanism for bacterial transmembrane signaling distinct from previously described models, thus expanding our understanding of signal transduction across the membrane, a fundamental requirement in many important biological processes.
THE RACIALIZATION OF PUBLIC DISCOURSE
Authors: Padovan Dario , Alietti Alfredo
Published: April 2012

The objective of this research is to understand the nature and diffusion of antisemitism and Islamophobia in Italy. It is based on 1528 interviews among a representative sample of the Italian population stratified according to age, gender, and residence. The questionnaire used was built by a set of different scales: antisemitic, Islamophobic, and three others scales to take into account authoritarian, ethnocentric, and anomic attitudes. To test assumptions regarding the impact of these predictors of antisemitic and Islamophobic prejudice, it was decided to adopt the statistical technique of path analysis. Outcomes of our research draw attention on the distribution of antisemitism and Islamophobia among Italian people, their nature as a combination of old and new prejudices, and their linking with broader sets of attitudes such as anomie, ethnocentrism, and authoritarianism.
Revaluation manipulations produce emergence of underselected stimuli following simultaneous discrimination in humans
Authors: Reed Phil , Reynolds Gemma , Fermandel Louise
Published: April 2012

Stimulus overselectivity occurs when only one of potentially many aspects of the environment controls behaviour. In four experiments, human participants were trained and tested on a trial-and-error simultaneous discrimination task involving two two-element compound stimuli. Overselectivity emerged in all experiments (i.e., one element from the reinforced compound controlled behaviour at the expense of the other). Following revaluation (extinction) of the previously overselected stimulus, behavioural control by the underselected stimulus element emerged without any direct training of that stimulus element. However, while a series of extinction manipulations targeting the revaluation of the overselected stimulus produced differential extinction of that stimulus, they did not result in differential emergence of the previously underselected stimuli. The results are discussed with respect to the theoretical implications for attention-based accounts of overselectivity.
A 250-year argument: Belief, behavior, and the bootstrap
Authors: Efron Bradley
Published: April 2012

The year 2013 marks the 250th anniversary of Bayes rule, one of the two fundamental inferential principles of mathematical statistics. The rule has been influential over the entire period—and controversial over most of it. Its reliance on prior beliefs has been challenged by frequentism, which focuses instead on the behavior of specific estimates and tests under repeated use. Twentieth-century statistics was overwhelmingly behavioristic, especially in applications, but the twenty-first century has seen a resurgence of Bayesianism. Some simple examples are used to show what’s at stake in the argument. The bootstrap, a computer-intensive inference machine, helps connect Bayesian and frequentist practice, leading finally to an empirical Bayes example of collaboration between the two philosophies.
Accurate extension of multiple sequence alignments using a phylogeny-aware graph algorithm
Authors: Löytynoja Ari , Vilella Albert J. , Goldman Nick
Published: April 2012

Motivation: Accurate alignment of large numbers of sequences is demanding and the computational burden is further increased by downstream analyses depending on these alignments. With the abundance of sequence data, an integrative approach of adding new sequences to existing alignments without their full re-computation and maintaining the relative matching of existing sequences is an attractive option. Another current challenge is the extension of reference alignments with fragmented sequences, as those coming from next-generation metagenomics, that contain relatively little information. Widely used methods for alignment extension are based on profile representation of reference sequences. These do not incorporate and use phylogenetic information and are affected by the composition of the reference alignment and the phylogenetic positions of query sequences.

Results: We have developed a method for phylogeny-aware alignment of partial-order sequence graphs and apply it here to the extension of alignments with new data. Our new method, called PAGAN, infers ancestral sequences for the reference alignment and adds new sequences in their phylogenetic context, either to predefined positions or by finding the best placement for sequences of unknown origin. Unlike profile-based alternatives, PAGAN considers the phylogenetic relatedness of the sequences and is not affected by inclusion of more diverged sequences in the reference set. Our analyses show that PAGAN outperforms alternative methods for alignment extension and provides superior accuracy for both DNA and protein data, the improvement being especially large for fragmented sequences. Moreover, PAGAN-generated alignments of noisy next-generation sequencing (NGS) sequences are accurate enough for the use of RNA-seq data in evolutionary analyses.

Availability: PAGAN is written in C++, licensed under the GPL and its source code is available at http://code.google.com/p/pagan-msa.

Contact:  ari.loytynoja@helsinki.fi

Supplementary information:  Supplementary data are available at Bioinformatics online.
Phenology ofXylella fastidiosaand Its Vector Around California Almond Nurseries: An Assessment of Plant Vulnerability to Almond Leaf Scorch Disease
Authors: Krugner R. , Ledbetter C. A. , Chen J. , Shrestha A.
Published: April 2012

Management of almond leaf scorch disease requires knowledge of all possible infection pathways. The disease is caused by the xylem-limited bacterium Xylella fastidiosa, which is transmitted by several species of sharpshooters. The objectives of this research were to elucidate the fate of bacteria in planta after inoculations in almond nursery plants and to determine patterns of insect vector population dynamics and temporal distribution of X. fastidiosa–infected plants relative to host plant assemblages in habitats surrounding commercial nurseries. In an experimental nursery, disease incidence was markedly affected by rootstock type. Prior to bud grafting, ‘Nemaguard’ rootstock seedlings were not susceptible to bacterial infection. After bud grafting with a susceptible scion (‘Sonora’), scions were susceptible to infection regardless of rootstock genotype. Surveys near commercial nurseries revealed that only habitats with permanent grass cover sustained vector populations throughout the season. A total of 87 plant samples tested positive for X. fastidiosa (6.3%) using enzyme-linked immunosorbent assay (ELISA), with a higher number of X. fastidiosa–infected plants found in weedy alfalfa fields than in other habitat types. Among plant species infected by X. fastidiosa, 33% were winter annuals, 45% were biennials or perennials, and 22% were summer annuals. Collectively, these findings identified a potential pathway for X. fastidiosa infection of almonds in nursery situations.
First Report Regarding Potato Scab Caused by Streptomyces acidiscabies in Uruguay
Authors: Lapaz M. I. , Verdier E. , Pianzzola M. J.
Published: April 2012

Potato scab disease is caused by gram-positive filamentous bacteria in the genus Streptomyces. A great variety of species cause this disease, but Streptomyces scabies is the most ancient of these pathogens and can be found in a worldwide distribution, whereas S. turgidiscabies and S. acidiscabies are newly emerged pathogens (2). During the autumn of 2010, potato (Solanum tuberosum) crops had large economic losses by common scab, corresponding to 29% of the total potato-cultivation area (according to our survey), which was unusual in Uruguay. Specifically, the disease was very aggressive and the tubers showed particularly deep scab lesions. We isolated the Streptomyces species present in these particular scab lesions of tubers collected in July 2010 from one of the three potato cultivation areas (San José). A total of 19 Streptomyces spp. strains were isolated and identified using classical and molecular techniques. Morphological characteristics of colonies and microscopic structure of the mycelium were observed (1). Molecular characterization by conventional PCR was carried out using primers directed to specific regions of the 16S rRNA gene for the genus Streptomyces, Aci1: (5′-TCACTCCTGCCTGCATGGGCG-3′) and Aci2: (5′-CGACAGCTCCCTCCCACAAG-3′). Also, regions of two pathogenicity genes, namely txtAB and nec1, were amplified and confirmed by sequencing (2). Additionally, melanin production and pathogenicity of the isolates was determined by inoculation of potato discs (1). Six of the 19 strains succeeded in PCR amplification with primers specific to Streptomyces acidiscabies, which has white, aerial hypha and flexuous spore chains. These strains did not produce melanin on tyrosine agar media. The amplified fragments for 16S rRNA and pathogenicity genes from one representative strain 61 were sequenced. BLASTn analysis of the 16S rRNA gene sequence obtained of the strain 61 (Accession No. JN206667) showed the highest similarity (100%) with S. acidiscabies type strain 84-01-182 (GenBank Accession No. FJ007427.1). Pathogenicity of the isolate was tested on tuber slices. The isolate was grown on YME for 5 to 7 days at 28°C and agar plugs from the sporulating colonies were inverted onto excised tuber tissue. Disks were incubated at 28°C in the dark and the presence of necrosis was evaluated after 5 days (1). All tuber slice assays were repeated three times. The noninoculated control tuber slices did not show any necrosis, while those inoculated with the strain did. To our knowledge, this is the first report of S. acidiscabies causing potato scab disease in Uruguay.

References: (1) D. H. Park et al. Plant Dis. 87:1290, 2003. (2) L. A. Wanner. Phytopathology 96:1361, 2006.
Release profile and characteristics of electrosprayed particles for oral delivery of a practically insoluble drug
Authors: Bohr Adam , Kristensen Jakob , Dyas Mark , Edirisinghe Mohan , Stride Eleanor
Published: April 2012

Poly(lactic-co-glycolic acid) (PLGA) microspheres containing celecoxib were prepared via electrospraying, and the influence of three processing parameters namely flow rate, solute concentration and drug loading, on the physico-chemical properties of the particles and the drug-release profile was studied. Microspheres with diameters between 2 and 8 μm were produced and a near-monodisperse size distribution was achieved (polydispersivity indices of 6–12%). Further, the inner structure of the particles showed that the internal porosity of the particles increased with increasing solvent concentration. X-ray powder diffraction (XRPD) analysis indicated that the drug was amorphous and remained stable after eight months of storage. Drug release was studied in USP 2 (United States Pharmacopeia Dissolution Apparatus 2) dissolution chambers, and differences in release profiles were observed depending on the parametric values. Changes in release rate were found to be directly related to the influence of the studied parameters on particle size and porosity. The results indicate that electrospraying is an attractive technique for producing drug-loaded microspheres that can be tailored towards an intended drug-delivery application. Compared with the more conventional spray-drying process, it provides better control of particle characteristics and less aggregation during particle formation. In particular, this study demonstrated its suitability for preparing capsules in which the drug is molecularly dispersed and released in a sustained manner to facilitate improved bioavailability.
Temperature-Sensitive Gels for Intratumoral Delivery ofβ-Lapachone: Effect of Cyclodextrins and Ethanol
Authors: Cunha-Filho Marcilio S. S. , Alvarez-Lorenzo Carmen , Martínez-Pacheco Ramón , Landin Mariana
Published: April 2012

This work evaluated the potential of Pluronics (varieties F127 and P123) in combination with solubilizing agents to be used as syringeablein situgelling depots of intratumoralβ-lapachone (βLAP). Pluronic dispersions prepared at various concentrations in the absence and the presence of ethanol and randomly methylatedβ-cyclodextrin (RMβCD) were characterized regarding their rheological properties, drug solubilization capacity, andin vitrorelease. Pluronic F127 (18–23%) formulations combined high ability to solubilizeβLAP (enhancement solubility factor up to 50), adequate gel temperature range (over 25°C), and gel strength at 37°C enough to guarantee the permanence of the formulation in the administration site for a period of time.βLAP release rate was finely tuned by the concentration of the polymer and the addition of RMβCD (diffusion coefficient ranging between 9 and 69 μg·cm−2). The ethanol increasesβLAP release rate but simultaneously led to weak gels. This paper shows thatβLAP formulations involving temperature-reversible Pluronic gels may be suitable for intratumoral drug delivery purposes.
Immobilized Horseradish Peroxidase on Discs of Polyvinyl Alcohol-Glutaraldehyde Coated with Polyaniline
Authors: Caramori Samantha Salomão , Fernandes Kátia Flávia , de Carvalho Junior Luiz Bezerra
Published: April 2012

Discs of network polyvinyl alcohol-glutaraldehyde (PVAG) were synthesized and coated with polyaniline (PANI) using glutaraldehyde as a chemical arm (PVAG-PANIG-HRP disc). The best conditions for the immobilization were established as about 1.0 mg mL−1of protein, for 60 min and pH 5.5. The soluble enzyme lost all of its activity after incubation at 70°C for 15 min, whereas the PVAG-PANIG-HRP disc retained about half of the initial activity for pyrogallol. The same PVAG-PANIG-HRP disc was used consecutively three times without any activity lossbut presented 25% of the initial activity after the 7th use. PVAG-PANIG-HRP disc retained approximately 80% and 60% of its initial activity after 60 and 80 days of storage, respectively. Resorcinol, m-cresol, catechol, pyrogallol,α-naphthol,βnaphthol, and 4, 4′-diaminodiphenyl benzidine were efficiently oxidized by the PVAG-PANIG-HRP disc (from about 70% to 90%), and it was less efficient towards aniline, phenol, and 2-nitrosonaphthol.
Impact of the Project P.A.T.H.S. in the Junior Secondary School Years: Objective Outcome Evaluation Based on Eight Waves of Longitudinal Data
Authors: Shek Daniel T. L. , Ma Cecilia M. S.
Published: April 2012

To assess the effectiveness of the Tier 1 Program of the Project P.A.T.H.S., a randomized group trial with eight waves of data collected was carried out. At the fifth year of data collection, 19 experimental schools (n=2, 662 students) and 24 control schools (n=3, 272 students) participated in the study. Analyses based on individual growth curve modeling showed that participants in the experimental schools displayed better positive youth development than did participants in the control schools in terms of different indicators derived from the Chinese Positive Youth Development Scale, including moral competence and behavioral competence and cognitive behavioral competencies. Significant results were also found when examining the trajectories of psychological development among control and experimental participants who perceived the program to be beneficial. Findings based on longitudinal objective outcome evaluation strongly suggest that the Project P.A.T.H.S. is effective in promoting positive development in Hong Kong secondary school students.