bluuebunny/crossref_metadata_2025 huggingface dataset:
Nongeminate recombination in neat P3HT and P3HT:PCBM blend films
Authors: Gorenflot Julien , Heiber Michael C. , Baumann Andreas , Lorrmann Jens , Gunz Matthias , Kämpgen Andreas , Dyakonov Vladimir , Deibel Carsten
Published: April 2014

The slow decay of charge carriers in polymer–fullerene blends measured in transient studies has raised a number of questions about the mechanisms of nongeminate recombination in these systems. In an attempt to understand this behavior, we have applied a combination of steady-state and transient photoinduced absorption measurements to compare nongeminate recombination behavior in films of neat poly(3-hexyl thiophene) (P3HT) and P3HT blended with [6,6]-phenyl-C61 butyric acid methyl ester (PCBM). Transient measurements show that carrier recombination in the neat P3HT film exhibits second-order decay with a recombination rate coefficient that is similar to that predicted by Langevin theory. In addition, temperature dependent measurements indicate that neat films exhibit recombination behavior consistent with the Gaussian disorder model. In contrast, the P3HT:PCBM blend films are characterized by a strongly reduced recombination rate and an apparent recombination order greater than two. We then assess a number of previously proposed explanations for this behavior including phase separation, carrier concentration dependent mobility, non-encounter limited recombination, and interfacial states. In the end, we propose a model in which pure domains with a Gaussian density of states are separated by a mixed phase with an exponential density of states. We find that such a model can explain both the reduced magnitude of the recombination rate and the high order recombination kinetics and, based on the current state of knowledge, is the most consistent with experimental observations.
A simple model for voltage-dependent carrier collection efficiency in solar cells
Authors: McCarthy R. F. , Hillhouse H. W.
Published: April 2014

Here, we present a simple, yet powerful model developed to calculate collection efficiencies for photogenerated charge carriers in semiconductor devices. In the model, we define a new collection length, which is calculated using transit times that depend on both drift and diffusion for charge collection. The model accounts for a non-uniform electric field determined by the depletion approximation. The voltage-dependence of the photocurrent can be calculated using appropriate given photogeneration rate, and our results were found to match very closely with those calculated using a finite difference solution of the full device equations. The transit time model reported here leads to fully analytical equations for the collection length. They allow one to quickly explore wide ranges of parameters including mobility, minority carrier lifetime, and device thickness. The simplicity of this model allows it to be applied to other devices architectures as well. In fact, the motivating factor to develop the model was to quickly illuminate the advantages and disadvantages of various device designs, from nanostructured photovoltaics to light trapping strategies, and plasmonic enhancements.
Study of the confined states in AlxGa1−xAs/GaAs/vacuum surface quantum well
Authors: Xiong D.-Y. , Wang J.-Q.
Published: April 2014

In this paper, we investigate the optical properties of confined electronic states in ultra-thin Al0.27Ga0.73As/GaAs/vacuum surface quantum wells by using photoreflectance spectroscopy at room temperature. Well-resolved doublet structures were found in the spectra. The energy of the features increases with decreasing well width in agreement with the predictions of a model of the transition energy between confined electron and hole states in a surface quantum well. Both the transition broadening and intensity behaviors are also well explained by the effective mass approximation theory. The offset between the un-perturbed theoretical transition energy and the experimental data has been explained by surface-state interaction effects. Moreover, the fact that the light hole ground state in the surface quantum well can be pushed out from the surface quantum well has been directly observed experimentally.
Thermoelectric power factor enhancement with gate-all-around silicon nanowires
Authors: Curtin Benjamin M. , Bowers John E.
Published: April 2014

The thermoelectric properties of gate-all-around silicon nanowires (Si NWs) are calculated to determine the potential for significant power factor enhancement. The Boltzmann transport equation and relaxation time approximation are employed to develop an electron transport model used to determine the field-effect mobility, electrical conductivity, Seebeck coefficient, and power factor for Si NWs with cross-sectional areas between 4 nm × 4 nm and 12 nm × 12 nm and a range of gate biases. Electrical conductivity for the gated Si NWs was much higher than that of doped Si due to the lack of ionized impurities and correspondingly greater carrier mobility. A significant increase in electrical conductivity with decreasing Si NW cross-sectional area was also observed due to a large increase in the average carrier density. For all Si NWs, the Seebeck coefficient was lower than that of doped bulk Si due to the different energy dependence between ionized impurity and phonon-mediated scattering processes. This decrease was also confirmed with Seebeck coefficient measurements of multigated Si NWs and n-type Si thin-films. Quantum confinement was also found to increase the Seebeck coefficient for <8 nm × 8 nm Si NWs and also at high charge densities. A maximum power factor of 6.8 × 10−3 W m−1 K−2 was calculated for the 6 nm × 6 nm Si NWs with typical Si/SiO2 interface roughness, which is 2–3 × those obtained experimentally for bulk Si. The power factor was also found to greatly depend on surface roughness, with a root-mean-square roughness of <0.8 nm necessary for power factor enhancement. An increase in ZT may also be possible if a low thermal conductivity can be obtained with minimal surface roughness.
Cavity optomechanics in gallium phosphide microdisks
Authors: Mitchell Matthew , Hryciw Aaron C. , Barclay Paul E.
Published: April 2014

We demonstrate gallium phosphide (GaP) microdisk optical cavities with intrinsic quality factors >2.8 × 105 and mode volumes <10(λ/n)3, and study their nonlinear and optomechanical properties. For optical intensities up to 8.0 × 104 intracavity photons, we observe optical loss in the microcavity to decrease with increasing intensity, indicating that saturable absorption sites are present in the GaP material, and that two-photon absorption is not significant. We observe optomechanical coupling between optical modes of the microdisk around 1.5 μm and several mechanical resonances, and measure an optical spring effect consistent with a theoretically predicted optomechanical coupling rate g0/2π∼30 kHz for the fundamental mechanical radial breathing mode at 488 MHz.
Geometrical optimization of a local ballistic magnetic sensor
Authors: Kanda Yuhsuke , Nomura Tatsuya , Kimura Takashi , Hara Masahiro
Published: April 2014

We have developed a highly sensitive local magnetic sensor by using a ballistic transport property in a two-dimensional conductor. A semiclassical simulation reveals that the sensitivity increases when the geometry of the sensor and the spatial distribution of the local field are optimized. We have also experimentally demonstrated a clear observation of a magnetization process in a permalloy dot whose size is much smaller than the size of an optimized ballistic magnetic sensor fabricated from a GaAs/AlGaAs two-dimensional electron gas.
Maximizing domain-wall speed via magnetic anisotropy adjustment in Pt/Co/Pt films
Authors: Kim Duck-Ho , Yoo Sang-Cheol , Kim Dae-Yun , Moon Kyoung-Woong , Je Soong-Geun , Cho Cheong-Gu , Min Byoung-Chul , Choe Sug-Bong
Published: April 2014

We report an experimental observation that indicates that a direct relation exists between the speed of the magnetic domain-wall (DW) motion and the magnitude of the perpendicular magnetic anisotropy (PMA) in Pt/Co/Pt films. It is found that by changing the thicknesses of the nonmagnetic Pt layers, the PMA magnitude can be varied significantly and the field-driven DW speed can also be modified by a factor of up to 50 under the same magnetic field. Interestingly, the DW speed exhibits a clear scaling behavior with respect to the PMA magnitude. A theory based on the DW creep criticality successfully explains the observed scaling exponent between the DW speed and the PMA magnitude. The presented results offer a method of maximizing the DW speed in DW-mediated nanodevices without altering the thickness of the magnetic Co layer.
Enhanced fluorescence from dye molecules by Au nanoparticles on asymmetric double-stranded DNA and mechanism
Authors: Guo J. H. , Liu L. Z. , Zhu X. B. , Wu X. L. , Chu Paul K.
Published: April 2014

Gold nanoparticles (NPs) prepared on asymmetric DNA double helical structures show some twinning structures and sharp corners because of the low processing temperature. The distance between individual NPs varies between 2 and 4 nm, and these NPs form clusters with a size of ∼40 nm. The DNA structures also provide docking sites for the fluorescent dye. The dependence of the fluorescence enhancement on the distance between the NPs and dye molecules is investigated. The maximum enhancement factor is 5.8 when the distance between the dye and Au NP surface is 3.4 nm and the results are consistent with theoretical simulation.
Mobilities in ambipolar field effect transistors based on single-walled carbon nanotube network and formed on a gold nanoparticle template
Authors: Wongsaeng Chalao , Singjai Pisith
Published: April 2014

Ambipolar field effect transistors based on a single-walled carbon nanotube (SWNT) network formed on a gold nanoparticle (AuNP) template with polyvinyl alcohol as a gate insulator were studied by measuring the current–gate voltage characteristics. It was found that the mobilities of holes and electrons increased with increasing AuNP number density. The disturbances in the flow pattern of the carbon feedstock in the chemical vapor deposition growth that were produced by the AuNP geometry, resulted in the differences in the crystallinity and the diameter, as well as the changes in the degree of the semiconductor behavior of the SWNTs.
Pattern Dot Quantity Affects Auditory Facilitation Effects on Visual Object Representations
Authors: Takeshima Yasuhiro , Gyoba Jiro
Published: April 2014

Auditory stimuli often facilitate visual perception. Audiovisual integration requires spatial and/or temporal proximity between visual and auditory stimuli; additionally, sensory processing speed affects the audiovisual integration process. In the present study we examined the relationship between processing speed and the auditory facilitation effect on visual representations by manipulating dot quantity patterns. We hypothesized that the auditory facilitation effect would be observed in longer interstimulus interval conditions with more dot quantities. This is because more processing time would be required to integrate visual and auditory stimuli. During a backward masking paradigm used in experiment 1, the auditory facilitation effect depended on dot quantity among patterns and the interval between visual stimuli and masks. Moreover, differences in processing time required to integrate visual and auditory stimuli between dot quantities was confirmed from a same-different discrimination task in experiment 2. Therefore, dot quantity affects sensory processing time, and a longer processing time is required for integrating visual and auditory stimuli when visual dot quantity is high.
A Norming Study and Library of 203 Dance Movements
Authors: Christensen Julia F , Nadal Marcos , Cela-Conde Camilo José , Gomila Antoni
Published: April 2014

Dance stimuli have been used in experimental studies of (i) how movement is processed in the brain; (ii) how affect is perceived from bodily movement; and (iii) how dance can be a source of aesthetic experience. However, stimulus materials across—and even within—these three domains of research have varied considerably. Thus, integrative conclusions remain elusive. Moreover, concerns have been raised that the movements selected for such stimuli are qualitatively too different from the actual art form dance, potentially introducing noise in the data. We propose a library of dance stimuli which responds to the stimuli requirements and design criteria of these three areas of research, while at the same time respecting a dance art–historical perspective, offering greater ecological validity as compared with previous dance stimulus sets. The stimuli are 5–6 s long video clips, selected from genuine ballet performances. Following a number of coding experiments, the resulting stimulus library comprises 203 ballet dance stimuli coded in (i) 25 qualitative and quantitative movement variables; (ii) affective valence and arousal; and (iii) the aesthetic qualities beauty, liking, and interest. An Excel spreadsheet with these data points accompanies this manuscript, and the stimuli can be obtained from the authors upon request.
Changes in Context and Perception of Maximum Reaching Height
Authors: Wagman Jeffrey B , Day Brian M
Published: April 2014

Successfully performing a given behavior requires flexibility in both perception and behavior. In particular, doing so requires perceiving whether that behavior is possible across the variety of contexts in which it might be performed. Three experiments investigated how (changes in) context (ie point of observation and intended reaching task) influenced perception of maximum reaching height. The results of experiment 1 showed that perceived maximum reaching height more closely reflected actual reaching ability when perceivers occupied a point of observation that was compatible with that required for the reaching task. The results of experiments 2 and 3 showed that practice perceiving maximum reaching height from a given point of observation improved perception of maximum reaching height from a different point of observation, regardless of whether such practice occurred at a compatible or incompatible point of observation. In general, such findings show bounded flexibility in perception of affordances and are thus consistent with a description of perceptual systems as smart perceptual devices.
Familiarity, Expertise, and Change Detection: Change Deafness is Worse in Your Native Language
Authors: Neuhoff John G , Schott Steven A , Kropf Adam J , Neuhoff Emily M
Published: April 2014

We first replicated the language-familiarity effect for voice discrimination and found better voice discrimination in familiar languages. However, when listeners were not cued to listen for changes, both English and Spanish speakers exhibited greater change deafness in their familiar language. Results suggest that lexical/semantic attention in a familiar language and increased indexical processing in an unfamiliar language can produce greater change deafness in familiar languages.
Evaluating Training Methods for Facial Image Comparison: The Face Shape Strategy Does Not Work
Authors: Towler Alice , White David , Kemp Richard I
Published: April 2014

Human performance on unfamiliar face matching is known to be highly error prone. However, in organisations where staff are required to perform this task as part of their daily work, attempts are often made to mitigate risk by providing training. Importantly, the methods used in these training courses have not been subjected to empirical validation. In this study we evaluate a common component of many training programmes which encourages viewers to classify face shape. Our results show very low agreement in face shape classification, both within and between participants, and across repeated presentations of a single image to a single participant. Furthermore, face shape classification training did not improve face matching accuracy, suggesting that the face shape strategy does not facilitate identification.
Solvent-free Synthesis of Novel Benzothiazole-substituted 4-Thiazolidinones Using Nano Silica-bonded 5-n-Propyl-octahydro-pyrimido[1,2-a]azepinium Chloride as Catalyst
Authors: Baharfar Robabeh , Shariati Narges
Published: April 2014

A series of novel benzothiazole-substituted 4-thiazolidinones were synthesised by the one-pot reaction of rhodanine-3-acetic acid derivatives, 2-aminothiophenol, and triphenyl phosphite in the presence of nano silica-bonded 5-n-propyl-octahydro-pyrimido[1,2-a]azepinium chloride (NSB-DBU) as heterogeneous reusable nanocatalyst under solvent-free conditions in high yields.
Characterization of the key aroma compounds in pork soup stock by using an aroma extract dilution analysis
Authors: Takakura Yukiko , Osanai Hiroki , Masuzawa Takuya , Wakabayashi Hidehiko , Nishimura Toshihide
Published: April 2014

The aroma extract dilution analysis of an extract prepared from pork stock and subsequent experiments led to the identification of 15 aroma-active compounds in the flavor dilution factor range of 64–2048. Omission experiments to select the most aroma-active compounds from the 15 odor compounds suggested acetol, octanoic acid, δ-decalactone, and decanoic acid as the main active compounds contributing to the aroma of pork stock. Aroma recombination, addition, and omission experiments of these four aroma compounds in taste-reconstituted pork stock showed that each compound had an individual aroma profile. A comparison of the overall aroma between this recombined mixture and pork stock showed strong similarity, suggesting that the key aroma compounds had been successfully identified.
Changing doping‐related attitudes in soccer players: How can we get stable and persistent changes?
Authors: Horcajo Javier , de la Vega Ricardo
Published: April 2014

The aim of this experiment was to analyse the consequences of changing attitudes related to doping through thoughtful versus non‐thoughtful processes. Participants were young soccer players. They received a persuasive message either against or in favour of the legalisation of several doping behaviours in soccer (e.g., the use of anabolic androgenic steroid – AAS), and participants' level of elaboration (i.e., deliberative thinking) was manipulated in two different experimental (high vs. low) conditions. Attitudes towards the legalisation proposal were assessed immediately following the message and one week later. Results showed attitude change was a function of message direction and was relatively equivalent for both high and low elaboration participants immediately after reading the message. That is, those who received the message against legalisation showed significantly more unfavourable attitudes towards the proposal than did those who received the message in favour of legalisation regardless of the extent of elaboration. However, attitude change was found to be persistent only for high elaboration participants one week after message exposure. In the present paper, we discuss implications of changing attitudes related to doping depending on whether the change occurred through psychological processes that require either extensive or small amounts of deliberative thinking and elaboration.
Government open data and transparency: Oakeshott, civil association and the general will
Authors: O’Hara Kieron
Published: April 2014

This article considers recent trends in government towards openness and transparency, particularly with respect to the publication of open data, in the context of Michael Oakeshott's ideas of the nature of the state and the conditions for civility. It is argued that certain aspects of open data have pushed back against a trend towards the imposition of government goals upon its citizens, an imposition often justified in terms reminiscent of Rousseau's doctrine of the general will. Oakeshott's view of the state is contrasted with Rousseau’s, and the two frameworks used to locate recent innovations in digital government. Of these, only open data is supportive of civil association.
The F-BAR protein Hof1 tunes formin activity to sculpt actin cables during polarized growth
Authors: Graziano Brian R. , Yu Hoi-Ying E. , Alioto Salvatore L. , Eskin Julian A. , Ydenberg Casey A. , Waterman David P. , Garabedian Mikael , Goode Bruce L.
Published: April 2014

Asymmetric cell growth and division rely on polarized actin cytoskeleton remodeling events, the regulation of which is poorly understood. In budding yeast, formins stimulate the assembly of an organized network of actin cables that direct polarized secretion. Here we show that the Fer/Cip4 homology–Bin amphiphysin Rvs protein Hof1, which has known roles in cytokinesis, also functions during polarized growth by directly controlling the activities of the formin Bnr1. A mutant lacking the C-terminal half of Hof1 displays misoriented and architecturally altered cables, along with impaired secretory vesicle traffic. In vitro, Hof1 inhibits the actin nucleation and elongation activities of Bnr1 without displacing the formin from filament ends. These effects depend on the Src homology 3 domain of Hof1, the formin homology 1 (FH1) domain of Bnr1, and Hof1 dimerization, suggesting a mechanism by which Hof1 “restrains” the otherwise flexible FH1-FH2 apparatus. In vivo, loss of inhibition does not alter actin levels in cables but, instead, cable shape and functionality. Thus Hof1 tunes formins to sculpt the actin cable network.
Spontaneous Breathing with Biphasic Positive Airway Pressure Attenuates Lung Injury in Hydrochloric Acid–induced Acute Respiratory Distress Syndrome
Authors: Xia Jingen , Zhang Heng , Sun Bing , Yang Rui , He Hangyong , Zhan Qingyuan
Published: April 2014

Background:

It has been proved that spontaneous breathing (SB) with biphasic positive airway pressure (BIPAP) can improve lung aeration in acute respiratory distress syndrome compared with controlled mechanical ventilation. The authors hypothesized that SB with BIPAP would attenuate lung injury in acute respiratory distress syndrome compared with pressure-controlled ventilation.

Methods:

Twenty male New Zealand white rabbits with hydrochloric acid aspiration–induced acute respiratory distress syndrome were randomly ventilated using the BIPAP either with SB (BIPAP plus SB group) or without SB (BIPAP minus SB group) for 5 h. Inspiration pressure was adjusted to maintain the tidal volume at 6 ml/kg. Both groups received the same positive end-expiratory pressure level at 5 cm H2O for hemodynamic goals. Eight healthy animals without ventilatory support served as the control group.

Results:

The BIPAP plus SB group presented a lower ratio of dead space ventilation to tidal volume, a lower respiratory rate, and lower minute ventilation. No significant difference in the protein levels of interleukin-6 and interleukin-8 in plasma, bronchoalveolar lavage fluid, and lung tissue were measured between the two experimental groups. However, SB resulted in lower messenger ribonucleic acid levels of interleukin-6 (mean ± SD; 1.8 ± 0.7 vs. 2.6 ± 0.5; P = 0.008) and interleukin-8 (2.2 ± 0.5 vs. 2.9 ± 0.6; P = 0.014) in lung tissues. In addition, lung histopathology revealed less injury in the BIPAP plus SB group (lung injury score, 13.8 ± 4.6 vs. 21.8 ± 5.7; P < 0.05).

Conclusion:

In hydrochloric acid–induced acute respiratory distress syndrome, SB with BIPAP attenuated lung injury and improved respiratory function compared with controlled ventilation with low tidal volume. (Anesthesiology 2014; 120:1441-9)
Characterization of the definitive classical calpain family of vertebrates using phylogenetic, evolutionary and expression analyses
Authors: Macqueen Daniel J. , Wilcox Alexander H.
Published: April 2014

The calpains are a superfamily of proteases with extensive relevance to human health and welfare. Vast research attention is given to the vertebrate ‘classical’ subfamily, making it surprising that the evolutionary origins, distribution and relationships of these genes is poorly characterized. Consequently, there exists uncertainty about the conservation of gene family structure, function and expression that has been principally defined from work with mammals. Here, more than 200 vertebrate classical calpains were incorporated in phylogenetic analyses spanning an unprecedented range of taxa, including jawless and cartilaginous fish. We demonstrate that the common vertebrate ancestor had at least six classical calpains, including a single gene that gave rise to
CAPN11
,
1
,
2
and
8
in the early jawed fish lineage, plus
CAPN3
,
9
,
12
,
13
and a novel calpain gene, hereafter named
CAPN17
. We reveal that while all vertebrate classical calpains have been subject to persistent purifying selection during evolution, the degree and nature of selective pressure has often been lineage-dependent. The tissue expression of the complete classic calpain family was assessed in representative teleost fish, amphibians, reptiles and mammals. This highlighted systematic divergence in expression across vertebrate taxa, with most classic calpain genes from fish and amphibians having more extensive tissue distribution than in amniotes. Our data suggest that classical calpain functions have frequently diverged during vertebrate evolution and challenge the ongoing value of the established system of classifying calpains by expression.
Sunguru virus: a novel virus in the family Rhabdoviridae isolated from a chicken in north-western Uganda
Authors: Ledermann Jeremy P. , Zeidner Nord , Borland Erin M. , Mutebi John-Paul , Lanciotti Robert S. , Miller Barry R. , Lutwama Julius J. , Tendo Joseph M. , Andama Vincent , Powers Ann M.
Published: April 2014

Sunguru virus (SUNV), a novel virus belonging to the highly diverseRhabdoviridaefamily, was isolated from a domestic chicken in the district of Arua, Uganda, in 2011. This is the first documented isolation of a rhabdovirus from a chicken. SUNV is related to, but distinct from, Boteke virus and other members of the unclassified Sandjimba group. The genome is 11 056 nt in length and contains the five core rhabdovirus genes plus an additional C gene (within the ORF of a phosphoprotein gene) and a small hydrophobic protein (between the matrix and glycoprotein genes). Inoculation of vertebrate cells with SUNV resulted in significant viral growth, with a peak titre of 7.8 log10p.f.u. ml−1observed in baby hamster kidney (BHK) cells. Little to no growth was observed in invertebrate cells and in live mosquitoes, withAnopheles gambiaemosquitoes having a 47.4 % infection rate in the body but no dissemination of the virus to the salivary glands; this suggests that this novel virus is not arthropod borne as some other members of the familyRhabdoviridae.
Viral metagenomics analysis demonstrates the diversity of viral flora in piglet diarrhoeic faeces in China
Authors: Zhang Bin , Tang Cheng , Yue Hua , Ren Yupeng , Song Zhigang
Published: April 2014

To investigate the diversity of viral flora, we used metagenomics to study the viral communities in a pooled faecal sample of 27 diarrhoeic piglets from intensive commercial farms in China. The 15 distinct mammalian viruses identified in the pooled diarrhoeic sample were, in order of abundance of nucleic acid sequence, Porcine epidemic diarrhea virus (PEDV), sapovirus, porcine bocavirus-4 (PBoV-4), sapelovirus, torovirus, coronavirus, PBoV-2, stool-associated single-stranded DNA virus (poSCV), astrovirus (AstV), kobuvirus, posavirus-1, porcine enterovirus-9 (PEV-9), porcine circovirus-like (po-circo-like) virus, picobirnavirus (PBV) and Torque teno sus virus 2 (TTSuV-2). The prevalence rate of each virus was verified from diarrhoeic and healthy piglets by PCR assay. A mean of 5.5 different viruses were shed in diarrhoeic piglets, and one piglet was in fact co-infected with 11 different viruses. By contrast, healthy piglets shed a mean of 3.2 different viruses. Compared with samples from healthy piglets, the co-infection of PEDV and PBoV had a high prevalence rate in diarrhoea samples, suggesting a correlation with the appearance of diarrhoea in piglets. Furthermore, we report here for the first time the presence of several recently described viruses in China, and the identification of novel genotypes. Therefore, our investigation results provide an unbiased survey of viral communities and prevalence in faecal samples of piglets.
Full-length genomes of 16 hepatitis C virus genotype 1 isolates representing subtypes 1c, 1d, 1e, 1g, 1h, 1i, 1j and 1k, and two new subtypes 1m and 1n, and four unclassified variants reveal ancestral relationships among subtypes
Authors: Lu Ling , Li Chunhua , Xu Yan , Murphy Donald G.
Published: April 2014

We characterized the full-length genomes of 16 distinct hepatitis C virus genotype 1 (HCV-1) isolates. Among them, four represented the first full-length genomes for subtypes 1d (QC103), 1i (QC181), 1j (QC329) and 1k (QC82), and another four corresponded to subtypes 1c (QC165), 1g (QC78), 1h (QC156) and 1e (QC172). Both QC196 and QC87 were assigned into a new subtype 1m, and QC113 and QC74 into another new subtype 1n. The remaining four (QC60, QC316, QC152 and QC180) did not classify among the established subtypes and corresponded to four new lineages. Subtypes 1j, 1k, 1m, 1n and the unclassified isolate QC60 were identified in Haitian immigrants. In the updated HCV nomenclature of 2005, a total of 12 subtypes of HCV-1 were designated. Including the data from the present study, all but subtype 1f now have their full-length genomes defined. Further analysis of partial NS5B sequences available in GenBank denoted a total of 21 unclassified lineages, indicating the taxonomic complexity of HCV-1. Among them, six have had their full-length genomes characterized. Based on the available full-length genome sequences, a timescale phylogenetic tree was reconstructed which estimated important time points in the evolution of HCV-1. It revealed that subtype 1a diverged from its nearest relatives 135 years ago and subtype 1b diverged from its nearest relatives 112 years ago. When subtypes 1a, 1j, 1k, 1m, 1n and six close relatives (all but one from Haitian immigrants) were considered as a whole, the divergence time was 176 years ago. This diversification was concurrent with the time period when the transatlantic slave trade was active. When taking all the HCV-1 isolates as a single lineage, the divergence time was 326 years ago. This analysis suggested the existence of a recent common ancestor for subtype 1a and the Haitian variants; a co-origin for subtypes 1b, 1i and 1d was also implied.
Passive surface microseismic monitoring as a statistical problem: location of weak microseismic signals in the presence of strongly correlated noise
Authors: Kushnir Alexander , Varypaev Alexander , Dricker Ilya , Rozhkov Mikhail , Rozhkov Nikita
Published: April 2014

In this paper, we treat passive surface microseismic monitoring as a predominantly statistical problem of location sources of weak seismicity recorded in the presence of strongly correlated noise using dense seismic arrays. We introduce two statistically optimal algorithms (adaptive maximal likelihood algorithm and statistically optimal phase algorithm) and show that the traditional semblance‐based microseismic processing algorithm (Seismic Emission Tomography) is just an extreme case of the maximal likelihood algorithm for Gaussian white noise (i.e., noise that is stationary and uncorrelated in time and space). We evaluate location uncertainties of all three microseismic algorithms for different types of noise patterns and signal‐to‐noise ratios. For Gaussian white noise, the Seismic Emission Tomography algorithm performs well, demonstrating even slightly better location accuracy than statistically optimal techniques. Actual noise affecting seismic sensors during hydraulic fracturing is non‐stationary. It is correlated in time and space, and varies greatly in power and spectral content for different sensors of the array. We use Monte Carlo simulation to show that the location accuracy of statistically optimal algorithms can be 20 to 40 times better than for the Seismic Emission Tomography algorithm in the presence of man‐made surface noise during hydraulic fracturing.
An ideal free distribution explains the root production of plants that do not engage in a tragedy of the commons game
Authors: McNickle Gordon G. , Brown Joel S.
Published: April 2014

Below‐ground competition is intense and may dramatically reduce plant performance. However, there is still no consensus on the best strategies plants should use to maximize competitive ability in soil. Some suggest plants should grow roots according to nutrient availability, while others suggest plants should grow roots taking into account both nutrients and neighbours. Unambiguously, testing between these two alternative hypotheses has been challenging.

This manuscript had three objectives. First, we presented a model of root growth under competition that is based on an ideal free distribution (IFD). Secondly, we develop the concept of the best response curve as a tool for clearer experimental tests of plant responses to neighbours. Thirdly, we test these ideas by growing fast cycling Brassica rapa either alone or with neighbours to examine this species' root growth strategy both alone and under competition.

We hypothesize that those plants with no direct response to neighbours should grow roots according to an IFD. This means that if plants produce x roots in a soil volume of quality R, they should produce x/n roots in a soil volume of quality R/n. The experimental data were consistent with this prediction. Growing plants with neighbours was statistically identical to growing them with half as many nutrients. Thus, the only effect of neighbours was to reduce nutrient availability.

This model provides an alternative to previous game theoretic models and suggests an experimental protocol based on the concept of the best response curve. We hope that testing the game theoretic model with a clear alternative model will guide experiment and debate.

Synthesis. The data in the literature are mixed, with species sometimes responding to nutrients only, and sometimes responding interactively to both nutrients and neighbours. At present, we lack a general understanding of the causes or consequences of this diversity of strategies. We suggest that a greater understanding of trade‐offs among traits that are important for other biotic interactions (above‐ground competition, enemy defence, mutualisms) will lead to a greater understanding of why some species over‐proliferate roots when in competition but other species do not.
Nitrogen addition increases intraspecific competition in the invasive wetland plant Alternanthera philoxeroides, but not in its native congener Alternanthera sessilis
Authors: Wang AO , Jiang Xing‐Xing , Zhang Qiu‐Qiu , Zhou Jian , Li Hong‐Li , Luo Fang‐Li , Zhang Ming‐Xiang , Yu Fei‐Hai
Published: April 2014

Nitrogen is often released in pulses with different frequencies, and N supply pulses may affect growth, reproduction, and biomass allocation of plants. However, few studies have examined how N supply pulses affect intraspecific competition of clonal plants and whether such an effect depends on the N supply amount. We grew one (no competition) or 12 ramets (with intraspecific competition) of both an invasive clonal plant Alternanthera philoxeroides and its native congener Alternanthera sessilis in five different N treatments: control (no N addition), low/high amount with low/high frequencies (pulses). Nitrogen addition significantly increased the growth of both species, while intraspecific competition decreased it. Nitrogen addition significantly increased intraspecific competitive intensity of A. philoxeroides as measured by the log response ratio of growth traits, but did not affect that of A. sessilis. Despite the N supply amount, N pulses had little effect on the growth and thus intraspecific competition of the two species. Therefore, increasing N deposition may change population structure and dynamics and the invasion succession of A. philoxeroides, but changes in N pulses may not.
First comparison of the VennerTM A.P. AdvanceTM versus the Macintosh laryngoscope for intubations by non‐anaesthetists: A manikin study
Authors: Marshall Elizabeth M , O'Loughlin Edmond , Swann Alex D
Published: April 2014

Objective

The present study aims to study whether using a videolaryngoscope (A.P. Advance™) facilitates or hinders intubation by non‐anaesthetists inexperienced in its use.

Methods

Thirty doctors from Emergency and Intensive Care Medicine backgrounds performed laryngoscopy and tracheal intubation using the Macintosh laryngoscope (MAC), A.P. Advance™ Normal Blade (AP N) and A.P. Advance™ Difficult Airway Blade (AP DAB) in simulated normal and difficult airway manikins. The primary outcomes measured were time to successful tracheal intubation and failure to intubate within 3 min or three attempts. Secondary outcomes were number of intubation attempts, adjuncts used, glottic view and ease of intubation.

Results

There was a higher rate of failed intubation in the simulated difficult airway in participants using the AP N blade than either the MAC or AP DAB (23% vs 3% and 7%, P = 0.031). This was associated with a longer median time to intubate with the AP N and the AP DAB versus MAC (56.6, 50.2 vs 39.9 s, P = 0.007 and P = 0.041). In the normal airway median time to intubate was longest with the AP N (27.8 s), and this was significantly slower than the MAC (18.1 s, P = 0.003) and the AP DAB (17.3 s, P < 0.001). No one failed to intubate the normal manikin.

Conclusions

The use of the A.P. Advance™ videolaryngoscope should not be considered, without adequate prior training and experience, in the management of a difficult airway. The level of adequate training has yet to be established.
Predicting the potential geographic distribution of Thrips palmi in Korea, using the CLIMEX model
Authors: Park Jung‐Joon , Mo Hyoung‐ho , Lee Gwan‐Seok , Lee Sung‐Eun , Lee Joon‐Ho , Cho Kijong
Published: April 2014

Thrips palmi Karny, melon thrips was introduced and first recorded in 1993 in Korea. This species has become a serious pest of vegetable and ornamental crops. The CLIMEX simulation was applied to T. palmi to predict its potential geographic distribution in Korea under the Representative Concentration Pathway (RCP) 8.5 climate change scenario. In the CLIMEX simulation, the ecoclimatic index was calculated, and compared in each simulated year and each simulated location. The map comparisons show good agreements between simulated and present distributions of T. palmi, indicating that the CLIMEX model has promising potential for prediction of future distributions of this species in Korea. In the near future, until the year 2020, all the western and eastern parts of Korea show favorable to marginal suitability for T. palmi populations in the fields. After the year 2040, potential distributions shift from no persistence to favorable for establishment and persistence from coastal to interior regions of the Korean peninsula, except for a north‐eastern interior region which is the northernmost part of a high mountainous (Baekdu‐Daegan) area in Korea. Based on the simulation results, the geographical distribution of T. palmi will expand over its current weather restrictions in the near future under a severe climate change scenario. Thus, pest management measures and strategies should be re‐evaluated in Korea, and should include further studies on interspecific competition and ecosystem changes due to climate changes.
Risk factors for pancreatic infection in patients with severe acute pancreatitis: An analysis of 163 cases
Authors: Zeng Yan Bo , Zhan Xian Bao , Guo Xiao Rong , Zhang Hua Gao , Chen Yan , Cai Quan Cai , Li Zhao Shen
Published: April 2014

Objective

We aimed to identify the risk factors for predicting pancreatic infection in patients with severe acute pancreatitis (SAP).

Methods

In all, 163 patients with SAP were included and divided into two groups based on the presence or absence of pancreatic infection. Their demographic and clinical characteristics, laboratory examination results, complications and treatment modalities were collected from their medical records. Variables were initially screened by univariate analysis and those with statistical significance were then filtered by multivariate analysis to determine the independent risk factors for pancreatic infection in SAP.

Results

Patients having SAP with pancreatic infection had a lower partial pressure of arterial carbon dioxide (PaCO2), peripheral white blood cell count and alkaline phosphatase levels, together with a higher computed tomography severity index (CTSI) than those without pancreatic infection, while their lactate dehydrogenase (LDH) levels and blood urea nitrogen were much higher. Pancreatic infection was also more common in patients receiving late fluid resuscitation than in those receiving early fluid resuscitation. Multivariate analyses revealed that increased LDH level, high CTSI, delayed fluid resuscitation and hypoxemia were independent risk factors for pancreatic infection in SAP. The sensitivity, specificity, positive and negative predictive values for a model combining the parameters in predicting pancreatic infection were 84%, 97%, 88% and 96%, respectively, with a cut‐off value of 0.393, and the area under the receiver operating characteristic curve was 0.923.

Conclusion

Increased LDH, high CTSI, delayed fluid resuscitation and hypoxemia are independent risk factors for predicting pancreatic infection in patients with SAP.
Value of the patency capsule in pre‐evaluation for capsule endoscopy in cases of intestinal obstruction
Authors: Zhang Wei , Han Ze Long , Cheng Yang , Xu Yang Zhi , Xiao Kun , Li Ai Min , Wang Ya Dong , Li Yue , Liu Si De
Published: April 2014

Objective

Patency capsule (PC) is a tool to screen the patency of the gastrointestinal (GI) tract. Capsule endoscopy can be performed after the patency is confirmed by the patency capsule. We aimed to estimate the diagnostic value of PC based on the existing trials.

Methods

We searched PubMed, CENTRAL and EMBASE for studies that included patients with suspected small bowel stricture who were evaluated by both PC and a reference standard (following capsule endoscopy and/or surgical pathology and/or endoscopic findings) and who were eligible for inclusion. The quality of the eligible studies was assessed using the Quality Assessment for Diagnostic Accuracy Studies‐2 criteria. Sensitivity, specificity, likelihood ratios and the area under the receiver operating characteristic curve (AUROC) were calculated.

Results

Five studies including 203 patients fulfilled the eligibility criteria. The pooled data showed a PC sensitivity of 97% (95% CI 93–99%) and a specificity of 83% (95% CI 65–94%). The AUROC was 0.9557.

Conclusions

PC may be of diagnostic value in confirming the patency of the GI tract before capsule endoscopy. The routine use of PC might eliminate the contraindication of capsule endoscopy in many cases of intestinal obstruction.
Tumor MET expression profile predicts the outcome of non‐small cell lung cancer patients receiving epidermal growth factor receptor tyrosine kinase inhibitors
Authors: Chang Hyun , Zhang Xianglan , Cho Byoung Chul , Park Hee Jin , Kim Joo‐Hang
Published: April 2014

Background

This study assesses whether MET expression in tumor tissue is associated with an increased sensitivity to epidermal growth factor receptor (EGFR)‐tyrosine kinase inhibitors (TKIs) in non‐small‐cell lung cancer (NSCLC) patients.

Methods

This retrospective study included 69 NSCLC participants with available tumor tissue and data on treatment response and survival. MET and hepatocyte growth factor expression in tumor tissue were evaluated by immunohistochemistry.

Results

Positive tMET expression correlated with a shorter progression‐free survival (PFS; P = 0.003) and overall survival (OS; P = 0.05). Positive pY1234/1235 expression was significantly associated with a longer PFS (P = 0.031) and OS (P = 0.012). In multivariable analyses, tMET and pY1234/1235 expression were independent factors for PFS and OS, respectively. (tMET, PFS; P = 0.02, OS; P = 0.0007 and pY1234/1234, PFS; P = 0.01, OS; P = 0.004).

Conclusions

This study suggests that total and phosphorylated MET expression in tumor tissue is potentially useful for the selection of NSCLC patients who are likely to benefit from EGFR‐TKIs, irrespective of their EGFR status.
Reptiles in restored agricultural landscapes: the value of linear strips, patches and habitat condition
Authors: Jellinek S. , Parris K. M. , McCarthy M. A. , Wintle B. A. , Driscoll D. A.
Published: April 2014

Habitat restoration, including revegetation of linear strips and enlargement of remnant patches, may benefit native fauna in highly fragmented landscapes. Such restoration has occurred around the world, even though the relative importance of strips and patches of vegetation remains controversial. Using reptile communities from south‐eastern Australia, we assessed the conservation value of revegetation in strips and alongside remnant patches compared with remnant vegetation and cleared roadsides. We also examined the distance that reptiles occurred from remnant patches into linear vegetation. We found that reptile species richness and counts did not substantially differ between revegetated, remnant and cleared habitats, or between linear strip and patch treatments. This may indicate that species sensitive to land clearing have already been lost from the landscape. These results imply that if specialist species have already been lost, we may be unable to measure the effects of agriculture on biodiversity. Furthermore, revegetation with the expectation that fauna will recolonize may be unrealistic and translocations may be necessary. Unexpectedly, we recorded higher species richness and counts of rare reptile species in remnant linear strips as distance from remnant patches increased. Ground‐layer attributes were important for increasing reptile species richness and counts and in structuring reptile communities, explaining approximately three times as much variation as remnant shape or vegetation type (remnant, revegetated, cleared). Management agencies should protect and effectively manage remnant linear strips if rarer reptiles are to be retained, paying particular attention to ground‐layer attributes. The decision to include ground layers in future revegetation activities will be more important than the shape of restored areas.