bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of three fusarium crown rot causal agents and systemic translocation of deoxynivalenol following stem base infection of soft wheat
Authors: Beccari G. , Prodi A. , Pisi A. , Nipoti P. , Onofri A. , Nicholson P. , Pfohl K. , Karlovsky P. , Gardiner D. M. , Covarelli L.
Published: December 2017

Fusarium pseudograminearum, F. culmorum and F. graminearum are the most important fusarium crown rot (FCR) causal agents. They have the common ability to biosynthesize deoxynivalenol (DON). To elucidate the behaviour of each of the three species, a comparative study was carried out to investigate symptom progression, fungal systemic growth and translocation of DON following stem base inoculation of soft wheat. FCR symptoms were mainly localized in the inoculated area, which extended up to the second node for all inoculated species. Only the most aggressive strains caused symptoms up to the third node. Real‐time quantitative PCR showed that fungal colonization reached the third node for all the tested species, but a low percentage of plants showed colonization above the third node following inoculation with the most aggressive strains. Fungal growth was detected in symptomless tissues but none of the three species was able to colonize as far as the head tissues. However, even if the pathogens were not detected in the heads, DON was detected in head tissues of the plants inoculated with the most aggressive strains. These results demonstrate that F. pseudograminearum, F. culmorum and F. graminearum, under the same experimental conditions, follow a similar pattern of symptom progression, fungal colonization and DON translocation after stem base infection. Differences in the extent of symptoms, fungal colonization and mycotoxin distribution were mainly attributable to strain aggressiveness. These findings provide comparative information on the events following infection of the stem base of wheat by three of the most important FCR casual agents.
Which Schools and Pupils Respond to Educational Achievement Surveys?: A Focus on the English Programme for International Student Assessment Sample
Authors: Durrant Gabriele B. , Schnepf Sylke V.
Published: December 2017

Non-response is a major problem facing research in the social sciences including in education surveys. Hence, research is needed to understand non-response patterns better as well as non-response as a social phenomenon. Findings may contribute to improvements in the future designs of such surveys. Using logistic and multilevel logistic modelling we examine correlates of non-response at the school and pupil level in the important educational achievement survey the ‘Programme for International Student Assessment’ (PISA) for England. The analysis exploits unusually rich auxiliary information on all schools and pupils sampled for PISA, whether responding or not, from two large-scale administrative sources on pupils’ socio-economic background and results in national public examinations. This information correlates highly with the PISA target variable. Findings show that characteristics that are associated with non-response differ between the school and pupil levels. Our results also indicate that schools matter in explaining pupil level response, which is often ignored in non-response analysis. Our findings have important implications for future education surveys. For example, if replacement schools are used to improve response, our results suggest that it may be more important to match initial and replacement schools on the socio-economic composition of their pupils than on any of the factors that are currently used.
Bounded, Efficient and Multiply Robust Estimation of Average Treatment Effects Using Instrumental Variables
Authors: Wang Linbo , Tchetgen Tchetgen Eric
Published: December 2017

Instrumental variables are widely used for estimating causal effects in the presence of unmeasured confounding. Under the standard instrumental variable model, however, the average treatment effect is only partially identifiable. To address this, we propose novel assumptions that enable identification of the average treatment effect. Our identification assumptions are clearly separated from model assumptions that are needed for estimation, so researchers are not required to commit to a specific observed data model in establishing identification. We then construct multiple estimators that are consistent under three different observed data models, and multiply robust estimators that are consistent in the union of these observed data models. We pay special attention to the case of binary outcomes, for which we obtain bounded estimators of the average treatment effect that are guaranteed to lie between −1 and 1. Our approaches are illustrated with simulations and a data analysis evaluating the causal effect of education on earnings.
Production Forecasting for Shale Gas Reservoirs With Fast Marching-Succession of Steady States Method
Authors: Teng Bailu , Cheng Linsong , Huang Shijun , Andy Li Huazhou
Published: December 2017

In this paper, we introduce fast marching-succession of steady-states (FM-SSS) method to predict gas production from shale gas formations. The solutions of fast marching method (FMM) will describe the dynamic drainage boundary, and the succession of steady-state (SSS) method is applied to predict the gas production within the drainage boundary. As only the grids within drainage need to be taken into calculation at each time-step, this approach works much more efficiently than the implicit finite difference method, especially, at the early stage of production when the drainage is relatively small.We combine FMM with SSS to conduct reservoir simulation and predict gas production in shale gas reservoirs. The pressure profiles of transient flow are approximated with the pressure profiles of steady-state flow in our approach. The difference between the proposed method and the conventional SSS method is that we provide an efficient method to characterize the boundary conditions. In the conventional SSS method, the boundary pressure has to be measured, which is inconvenient for simulation purposes, whereas FM-SSS method takes the dynamic drainage as a changing boundary and approximates the drainage boundary pressure with initial reservoir pressure, such that the boundary condition can be numerically characterized. A major advantage of our approach is that it is unconditionally stable and more efficient than the implicit finite difference method because much smaller-scale linear equations need to be solved at each time-step.
Finite Element Analysis of Thermally Induced Stresses in the Near-Wellbore Region During Invasion of Mud Into Fractures
Authors: Wang Ze , Chen Yuanhang
Published: December 2017

A severe lost circulation event is usually associated with emanation and propagation of pre-existing or drilling induced fractures from the wellbore. To combat lost circulation and prevent further fracture propagation, a thorough understanding of the stress state in the near-wellbore region with fractures is imperative. However, it is not yet fully understood how temperature variation during the invasion of mud affects pre-existing or newly initiated fractures. A three-dimensional (3D) finite element (FE) analysis was conducted in this study to simulate the transport processes and state of stresses in the near-wellbore region during invasion of mud into fractures. To account for thermal effects, a thermo-poroelasticity model was coupled with flow and heat transfer models in the fractures. This study included a series of sensitivity analyses based on different formation properties and mud loss conditions to delineate the relative importance of different parameters on induced thermal stresses. It also evaluated potential risks of reinitiating fractures under various downhole conditions. The results demonstrate how the stresses redistribute as nonisothermal invasion of mud takes place in fractures. It shows that a temperature difference between the formation rock and the circulating muds can facilitate fracture propagation during invasion of mud. These results due to temperature change can also diminish the enhanced hoop stresses provided by wellbore strengthening (WBS) and other lost circulation prevention methods. Such information is vital to successful lost circulation management. The conclusions of this study are particularly relevant when a substantial temperature difference exists between circulating fluids and surrounding rock, as commonly seen in high-pressure, high-temperature, and deepwater wells.
Optimization of Electrode Configuration and Pulse Strength in Irreversible Electroporation for Large Ablation Volumes Without Thermal Damage
Authors: Yang Yongji , Moser Michael , Zhang Edwin , Zhang Wenjun , Zhang Bing
Published: December 2017

The aim of this study was to analyze five factors that are responsible for the ablation volume and maximum temperature during the procedure of irreversible electroporation (IRE). The five factors used in this study were the pulse strength (U), the electrode diameter (B), the distance between the electrode and the center (D), the electrode length (L), and the number of electrodes (N). A validated finite element model (FEM) of IRE was built to collect the data of the ablation volume and maximum temperature generated in a liver tissue. Twenty-five experiments were performed, in which the ablation volume and maximum temperature were taken as response variables. The five factors with ranges were analyzed to investigate their impacts on the ablation volume and maximum temperature, respectively, using analysis of variance. Response surface method (RSM) was used to optimize the five factors for the maximum ablation volume without thermal damage (the maximum temperature ≤ 50 °C for 90 s). U and L were found with significant impacts on the ablation volume (P < 0.001, and P = 0.009, respectively) while the same conclusion was not found for B, D and N (P = 0.886, P = 0.075 and P = 0.279, respectively). Furthermore, U, D, and N had the significant impacts on the maximum temperature with P < 0.001, P < 0.001, and P = 0.003, respectively, while same conclusion was not found for B and L (P = 0.720 and P = 0.051, respectively). The maximum ablation volume of 2952.9960 mm3 without thermal damage can be obtained by using the following set of factors: U = 2362.2384 V, B = 1.4889 mm, D = 7 mm, L = 4.5659 mm, and N = 3. The study concludes that both B and N have insignificant impacts (P = 0.886, and P = 0.279, respectively) on the ablation volume; U has the most significant impact (P < 0.001) on the ablation volume; electrode configuration and pulse strength in IRE can be optimized for the maximum ablation volume without thermal damage using RSM.
Growth of LaAlO3 on silicon via an ultrathin SrTiO3 buffer layer by molecular-beam epitaxy
Authors: Wang Zhe , Chen Zhen , Mei Antonio B. , Bai Xue , Kourkoutis Lena F. , Muller David A. , Schlom Darrell G.
Published: December 2017

(001)-oriented LaAlO3 films were grown epitaxially on (001) Si substrates utilizing an ultrathin 5 unit-cell-thick SrTiO3 buffer layer. The SrTiO3 layer was grown at ∼250 °C and annealed in vacuum at 550 °C, following an epitaxy-by-periodic-annealing procedure. Upon this buffer layer, the LaAlO3 layer was then grown by codeposition at 580 °C. The rocking curve of the as-grown LaAlO3 film exhibits a full width at half maximum value as small as 0.02°. Atomic force microscopy shows that the surface of the LaAlO3 film has a root-mean-square roughness of 1.3 Å. Scanning transmission electron microscopy reveals that the LaAlO3/SrTiO3 interface and the SrTiO3/Si interfaces are sharp. This high crystalline quality, twin-free, epitaxial LaAlO3 on SrTiO3 on silicon could be relevant to integrating oxides with multiple functionalities on silicon.
Dicarboxylic acids analyzed by time-of-flight secondary ions mass spectrometry. Part IV: Hexanedioic acid
Authors: Trindade Gustavo F. , Ferreira Jose M. , Abel Marie-Laure , Baker Mark A. , Watts John F.
Published: December 2017

Time-of-flight secondary ion mass spectrometry was carried out to analyze a commercially available hexanedioic acid (adipic acid) powder. Positive and negative polarity ion spectra were obtained using a 25 keV Bi3+ ion beam rastered over areas of 50 × 50 μm2. The main observed fragments were the protonated molecule [M+H]+ at 105 Da and the deprotonated molecule [M-H]− at 103 Da with their respective oligomers.
Deriving loudness growth functions from categorical loudness scaling data
Authors: Wróblewski Marcin , Rasetshwane Daniel M. , Neely Stephen T. , Jesteadt Walt
Published: December 2017

The goal of this study was to reconcile the differences between measures of loudness obtained with continuous, unbounded scaling procedures, such as magnitude estimation and production, and those obtained using a limited number of discrete categories, such as categorical loudness scaling (CLS). The former procedures yield data with ratio properties, but some listeners find it difficult to generate numbers proportional to loudness and the numbers cannot be compared across listeners to explore individual differences. CLS, where listeners rate loudness on a verbal scale, is an easier task, but the numerical values or categorical units (CUs) assigned to the points on the scale are not proportional to loudness. Sufficient CLS data are now available to assign values in sones, a scale proportional to loudness, to the loudness categories. As a demonstration of this approach, data from Heeren, Hohmann, Appell, and Verhey [J. Acoust. Soc. Am. 133, EL314–EL319 (2013)] were used to develop a CUsone metric, whose values were then substituted for the original CU values in reanalysis of a large set of CLS data obtained by Rasetshwane, Trevino, Gombert, Liebig-Trehearn, Kopun, Jesteadt, Neely, and Gorga [J. Acoust. Soc. Am. 137, 1899–1913 (2015)]. The resulting data are well fitted by power functions and are in general agreement with previously published results obtained with magnitude estimation, magnitude production, and cross modality matching.
“I’ve Had Bad Experiences With Team Sport”: Sport Participation, Peer Need-Thwarting, and Need-Supporting Behaviors Among Youth Identifying With Physical Disability
Authors: Orr Krystn , Tamminen Katherine A. , Sweet Shane N. , Tomasone Jennifer R. , Arbour-Nicitopoulos Kelly P.
Published: December 2017

This study was guided by self-determination theory to explore the sport experiences of youth with a physical disability and the role of peers within this context. Interviews were conducted with eight youths using a relational mapping technique and analyzed using a deductive thematic approach. Sport peers were broadly defined by the youth as individuals from a large age range and of all abilities. Youth perceived their sport peers to have dynamic roles throughout their participation in sport. The perceived roles of these sport peers included supporting and thwarting basic psychological needs, and influencing the youths’ processing of sport internalization. Findings focus on the complexity of peer need-thwarting and need-supporting interactions in sport for youth with physical disabilities. Overall, peers have a multifaceted role in the sport experiences of youth identifying with a physical disability and may, in some cases, thwart youths’ basic psychological needs.
Effects of Whey Protein Supplementation Associated With Resistance Training on Muscular Strength, Hypertrophy, and Muscle Quality in Preconditioned Older Women
Authors: Sugihara Junior Paulo , Ribeiro Alex S. , Nabuco Hellen C.G. , Fernandes Rodrigo R. , Tomeleri Crisieli M. , Cunha Paolo M. , Venturini Danielle , Barbosa Décio S. , Schoenfeld Brad J. , Cyrino Edilson S.
Published: December 2017

The purpose of this study was to investigate the effect of whey protein (WP) supplementation on muscular strength, hypertrophy, and muscular quality in older women preconditioned to resistance training (RT). In a randomized, double-blind, and placebo (PLA)-controlled design, 31 older women (67.4 ± 4.0 years, 62.0 ± 6.9 kg, 155.9 ± 5.7 cm, and 25.5 ± 2.4 kg/m2) received either 35 g of WP (n = 15) or 35 g of PLA (n = 16) over a 12-week study period while performing an RT program three times a week. Dietary intake, one-repetition maximum test, and skeletal muscle mass by dual-energy X-ray absorptiometry were assessed before and after the intervention period. Both groups showed significant (p < .05) improvements in skeletal muscle mass and total strength, and the WP group realized greater increases (p < .05) in these measures compared with PLA (skeletal muscle mass: WP = +4.8% vs. PLA = +2.3%; strength: WP = +8.7% vs. PLA = +4.9%). Muscular quality increased (p < .05) in both groups (WP = +2.9% vs. PLA = +1.5%) without statistical differences (p > .05) noted between conditions. We conclude that WP supplementation in combination with RT induces higher increases in both strength and hypertrophy in older women preconditioned to RT.
First and Second Step Characteristics of Amputee and Able-Bodied Sprinters
Authors: Strutzenberger Gerda , Brazil Adam , Exell Timothy , von Lieres und Wilkau Hans , Davies John D. , Willwacher Steffen , Funken Johannes , Müller Ralf , Heinrich Kai , Schwameder Hermann , Potthast Wolfgang , Irwin Gareth
Published: December 2017

Context: In sprint events, the first 2 steps are used to accelerate the center of mass horizontally and vertically. Amputee athletes cannot actively generate energy with their running-specific prosthesis. It is likely that sprint acceleration mechanics, including step asymmetry, are altered compared with able-bodied athletes. Purpose: To investigate spatiotemporal and kinetic variables of amputee compared with able-bodied sprinters. Methods: Kinematic and kinetic data of the first and second stance were collected from 15 able-bodied and 7 amputee sprinters (2 unilateral transfemoral, 4 unilateral transtibial, and 1 bilateral transtibial) with a motion-capture system (250 Hz) and 2 force plates (1000 Hz). In addition, bilateral asymmetry was quantified and compared between groups. Results: Compared with able-bodied athletes, amputee athletes demonstrated significantly lower performance values for 5- and 10-m times. Step length, step velocity, and step frequency were decreased and contact times increased. Peak horizontal force and relative change of horizontal velocity were decreased in both stances. Peak vertical force and relative change of vertical velocity were lower for the amputee than the able-bodied group during the first stance but significantly higher during the second stance. During the first stance, able-bodied and amputee sprinters displayed a similar orientation of the ground-reaction-force vector, which became more vertically orientated in the amputee group during second stance. Amputee sprinters showed significantly greater asymmetry magnitudes for vertical force kinetics compared with able-bodietd athletes. Conclusion: A running-specific prosthesis does not replicate the function of the biological limb well in the early acceleration phase.
The Effect of Training Loads on Performance Measures and Injury Characteristics in Rugby League Players: A Systematic Review
Authors: Booth Mark , Orr Rhonda , Cobley Stephen
Published: December 2017

Purpose: To conduct a systematic review into the effect of training load (TL) on both performance measures and injury characteristics in rugby league players. Methods: Based on PRISMA guidelines, a systematic search of electronic databases was performed from the earliest record to December 2016. Five electronic databases (MEDLINE, SPORTDiscus, CINAHL, Web of Science, and AusSportMed) were searched using keywords within the subcategories of population (rugby league players), intervention (training quantification), and outcomes (performance or injury). Original peer-reviewed published manuscripts were considered if they had a clear quantification of TL (eg, session rating of perceived exertion), clear measures of performance (tests of physiological parameters relative to rugby league players [eg, agility]), and/or injury characteristics (eg, injury incidence). Results: Twelve studies met the inclusion criteria. The highest TL was observed in preseason training phases. Higher TL elicited greater improvements in maximal aerobic power, vertical jump (in cm), and agility scores (in s). Higher TL was associated with higher incidence of muscular strains and joint sprains, lower-limb injuries, and overexertion and overuse injuries. Conclusions: Findings suggest a dose–response relationship between TL, physical performance, and injury characteristics. However, due to study and methodological limitations, the precise nature of this relationship is, as yet, inconclusive. Therefore, the development of uniform TL definition and quantification and further research is warranted.
Embodying Industrial Knowledge: An Epistemological Approach to the Formation of Body Knowledge in the Fitness Industry
Authors: Parviainen Jaana
Published: December 2017

This paper has two objectives: 1) to develop a coherent epistemological approach to clarify the concept of body knowledge and 2) to analyze the role of body knowledge in business-driven fitness environments. The epistemological analysis is built on phenomenological and feminist discussions on embodiment to clarify the power mechanisms and agency behind the profit-making interests of the fitness industry. I introduce two conceptions of body knowledge—bodily knowledge and embodied knowledge—that are on opposite ends of the same continuum. My analysis suggests that there are several reasons why embodied knowledge is fostered while bodily knowledge remains marginal in the fitness industry. The paper concludes that the business-driven work environment equips group fitness instructors with performative skills but offers few opportunities to develop professional judgment agency and expertise.
Successive Emergence of Ceftazidime-Avibactam Resistance through Distinct Genomic Adaptations in
bla
KPC-2
-Harboring Klebsiella pneumoniae Sequence Type 307 Isolates
Authors: Giddins Marla J. , Macesic Nenad , Annavajhala Medini K. , Stump Stephania , Khan Sabrina , McConville Thomas H. , Mehta Monica , Gomez-Simmonds Angela , Uhlemann Anne-Catrin
Published: December 2017

Ceftazidime-avibactam (CAZ-AVI) is a promising novel treatment for infections caused by carbapenem-resistant
Enterobacteriaceae
(CRE). Despite improved treatment outcomes compared to those achieved with aminoglycoside- and colistin-based regimens, the rapid evolution of CAZ-AVI resistance during treatment has previously been reported in
Klebsiella pneumoniae
sequence type 258 (ST258)
bla
KPC-3
-harboring isolates. Here, we report the stepwise evolution and isolation of two phenotypically distinct CAZ-AVI-resistant
Klebsiella pneumoniae
isolates from a patient with pancreatitis. All susceptible (
n
= 3) and resistant (
n
= 5) isolates were of the ST307 clonal background, a rapidly emerging clone. Taking advantage of short-read Illumina and long-read Oxford Nanopore sequencing and full-length assembly of the core chromosome and plasmids, we demonstrate that CAZ-AVI resistance first occurred through a 532G → T
bla
KPC-2
point mutation in
bla
KPC-2
(D179Y protein substitution) following only 12 days of CAZ-AVI exposure. While subsequent isolates exhibited substantially decreased meropenem (MEM) MICs (≤2 μg/ml), later cultures demonstrated a second CAZ-AVI resistance phenotype with a lower CAZ-AVI MIC (12 μg/ml) but also MEM resistance (MIC > 128 μg/ml). These CAZ-AVI- and MEM-resistant isolates showed evidence of multiple genomic adaptations, mainly through insertions and deletions. This included amplification and transposition of wild-type
bla
KPC-2
into a novel plasmid, an IS
1
insertion upstream of
ompK36
, and disruption of the
rfb
gene locus in these isolates. Our findings illustrate the potential of CAZ-AVI resistance to emerge in non-
K. pneumoniae
ST258 clonal backgrounds and alternative
bla
KPC
variants. These results raise concerns about the strong selective pressures incurred by novel carbapenemase inhibitors, such as avibactam, on isolates previously considered invulnerable to CAZ-AVI resistance. There is an urgent need to further characterize non-KPC-mediated modes of carbapenem resistance and the intrinsic bacterial factors that facilitate the rapid emergence of resistance during treatment.
An Attenuated Salmonella enterica Serovar Typhimurium Strain and Galacto-Oligosaccharides Accelerate Clearance of Salmonella Infections in Poultry through Modifications to the Gut Microbiome
Authors: Azcarate-Peril M. Andrea , Butz Natasha , Cadenas Maria Belen , Koci Matthew , Ballou Anne , Mendoza Mary , Ali Rizwana , Hassan Hosni
Published: December 2017

Salmonella
is estimated to cause one million foodborne illnesses in the United States every year.
Salmonella
-contaminated poultry products are one of the major sources of salmonellosis. Given the critical role of the gut microbiota in
Salmonella
transmission, a manipulation of the chicken intestinal microenvironment could prevent animal colonization by the pathogen. In
Salmonella
, the global regulator gene
fnr
(
f
umarate
n
itrate
r
eduction) regulates anaerobic metabolism and is essential for adapting to the gut environment. This study tested the hypothesis that an attenuated Fnr mutant of
Salmonella enterica
serovar Typhimurium (attST) or prebiotic galacto-oligosaccharides (GOS) could improve resistance to wild-type
Salmonella
via modifications to the structure of the chicken gut microbiome. Intestinal samples from a total of 273 animals were collected weekly for 9 weeks to evaluate the impact of attST or prebiotic supplementation on microbial species of the cecum, duodenum, jejunum, and ileum. We next analyzed changes to the gut microbiome induced by challenging the animals with a wild-type
Salmonella
serovar 4,[5],12:r:− (Nal
r
) strain and determined the clearance rate of the virulent strain in the treated and control groups. Both GOS and the attenuated
Salmonella
strain modified the gut microbiome but elicited alterations of different taxonomic groups. The attST produced significant increases of
Alistipes
and undefined
Lactobacillus
, while GOS increased
Christensenellaceae
and
Lactobacillus reuteri
. The microbiome structural changes induced by both treatments resulted in a faster clearance after a
Salmonella
challenge.

IMPORTANCE
With an average annual incidence of 13.1 cases/100,000 individuals, salmonellosis has been deemed a nationally notifiable condition in the United States by the Centers for Disease Control and Prevention (CDC). Earlier studies demonstrated that
Salmonella
is transmitted by a subset of animals (supershedders). The supershedder phenotype can be induced by antibiotics, ascertaining an essential role for the gut microbiota in
Salmonella
transmission. Consequently, modulation of the gut microbiota and modification of the intestinal microenvironment could assist in preventing animal colonization by the pathogen. Our study demonstrated that a manipulation of the chicken gut microbiota by the administration of an attenuated
Salmonella
strain or prebiotic galacto-oligosaccharides (GOS) can promote resistance to
Salmonella
colonization via increases of beneficial microorganisms that translate into a less hospitable gut microenvironment.
Autoinducer 2-Dependent Escherichia coli Biofilm Formation Is Enhanced in a Dual-Species Coculture
Authors: Laganenka Leanid , Sourjik Victor
Published: December 2017

Biofilms in nature typically consist of multiple species, and microbial interactions are likely to have crucial effects on biofilm development, structure, and functions. The best-understood form of communication within bacterial communities involves the production, release, and detection of signal molecules (autoinducers), known as quorum sensing. Although autoinducers mainly promote intraspecies communication, autoinducer 2 (AI-2) is produced and detected by a variety of bacteria, thus principally allowing interspecies communication. Here we show the importance of AI-2-mediated signaling in the formation of mixed biofilms by
Enterococcus faecalis
and
Escherichia coli
. Our results demonstrate that AI-2 produced by
E. faecalis
promotes collective behaviors of
E. coli
at lower cell densities, enhancing autoaggregation of
E. coli
but also leading to chemotaxis-dependent coaggregation between the two species. Finally, we show that formation of such mixed dual-species biofilms increases the stress resistance of both
E. coli
and
E. faecalis
.

IMPORTANCE
The role of interspecies communication in the development of mixed microbial communities is becoming increasingly apparent, but specific examples of such communication remain limited. The universal signal molecule AI-2 is well known to regulate cell-density-dependent phenotypes of many bacterial species but, despite its potential for interspecies communication, the role of AI-2 in the establishment of multispecies communities is not well understood. In this study, we explore AI-2 signaling in a dual-species community containing two bacterial species that naturally cooccur in their mammalian hosts, i.e.,
Escherichia coli
and
Enterococcus faecalis
. We show that active production of AI-2 by
E. faecalis
allows
E. coli
to perform collective behaviors at low cell densities. Additionally, AI-2- and chemotaxis-dependent coaggregation with
E. faecalis
creates nucleation zones for rapid growth of
E. coli
microcolonies in mixed biofilms and enhances the stress resistance of both species.
Identification of Residues Controlling Restriction versus Enhancing Activities of IFITM Proteins on Entry of Human Coronaviruses
Authors: Zhao Xuesen , Sehgal Mohit , Hou Zhifei , Cheng Junjun , Shu Sainan , Wu Shuo , Guo Fang , Le Marchand Sylvain J. , Lin Hanxin , Chang Jinhong , Guo Ju-Tao
Published: December 2017

Interferon-induced transmembrane proteins (IFITMs) are restriction factors that inhibit the infectious entry of many enveloped RNA viruses. However, we demonstrated previously that human IFITM2 and IFITM3 are essential host factors facilitating the entry of human coronavirus (HCoV) OC43. In a continuing effort to decipher the molecular mechanism underlying IFITM differential modulation of HCoV entry, we investigated the roles of structural motifs important for IFITM protein posttranslational modifications, intracellular trafficking, and oligomerization in modulating the entry of five HCoVs. We found that three distinct mutations in IFITM1 or IFITM3 converted the host restriction factors to enhance entry driven by the spike proteins of severe acute respiratory syndrome coronavirus (SARS-CoV) and/or Middle East respiratory syndrome coronavirus (MERS-CoV). First, replacement of IFITM3 tyrosine 20 with either alanine or aspartic acid to mimic unphosphorylated or phosphorylated IFITM3 reduced its activity to inhibit the entry of HCoV-NL63 and -229E but enhanced the entry of SARS-CoV and MERS-CoV. Second, replacement of IFITM3 tyrosine 99 with either alanine or aspartic acid reduced its activity to inhibit the entry of HCoV-NL63 and SARS-CoV but promoted the entry of MERS-CoV. Third, deletion of the carboxyl-terminal 12 amino acid residues from IFITM1 enhanced the entry of MERS-CoV and HCoV-OC43. These findings suggest that these residues and structural motifs of IFITM proteins are key determinants for modulating the entry of HCoVs, most likely through interaction with viral and/or host cellular components at the site of viral entry to modulate the fusion of viral envelope and cellular membranes.

IMPORTANCE
The differential effects of IFITM proteins on the entry of HCoVs that utilize divergent entry pathways and membrane fusion mechanisms even when using the same receptor make the HCoVs a valuable system for comparative investigation of the molecular mechanisms underlying IFITM restriction or promotion of virus entry into host cells. Identification of three distinct mutations that converted IFITM1 or IFITM3 from inhibitors to enhancers of MERS-CoV or SARS-CoV spike protein-mediated entry revealed key structural motifs or residues determining the biological activities of IFITM proteins. These findings have thus paved the way for further identification of viral and host factors that interact with those structural motifs of IFITM proteins to differentially modulate the infectious entry of HCoVs.
Socioeconomic differences in self-medication among middle-aged and older people: data from the China health and retirement longitudinal study
Authors: Chang Jie , Wang Qing , Fang Yu
Published: December 2017

Objectives

Self-medication with over-the-counter medicines (OTCs) and prescription-only medicines (POMs) are both pervasive in China, although the latter is an inappropriate practice. We examined the relationship between socioeconomic status (SES) and self-medication with OTCs versus POMs.

Methods

Multivariate logistic regressions based on the Andersen framework were estimated using a subsample of respondents aged 45 years and over from the China Health and Retirement Longitudinal Study collected between 2011 and 2013 (n=23 699). As dependent variables, we used OTC and POM consumption without a medical prescription. SES was operationalised by household income per capita and education. Control variables included health indicators, demographic characteristics, and health behaviours.

Results

In our study sample, 32.69% and 15.02% of people aged 45 years and over had self-medicated with OTCs and POMs in the 4 weeks before the survey, respectively. OTC use by income exhibited an inverse U shape. Respondents from middle income groups were more likely to self-medicate with OTCs compared with those from the lowest and highest income groups. In contrast, respondents from the lowest income group were more inclined to self-medicate with POMs. There was a clear trend towards more self-medication with OTCs, but not POMs, among those with higher educational attainment.

Conclusion

People with low income tended to rely on self-medication with POMs for treatment, which is risky and of low quality. A health education programme for older people, particularly those living in low-income households, aimed at improving the quality of self-medication behaviour is warranted. Urgent measures are needed to address the issue of easy access to POMs at community pharmacies, and to improve access to formal medical care among the low-income population.
Likelihood that expectations of informal care will be met at onset of caregiving need: a retrospective study of older adults in the USA
Authors: Abrahamson Kathleen , Hass Zachary , Sands Laura
Published: December 2017

Background

Ageing adults are likely to expect informal caregiving assistance from a friend or family member, reflecting the reality that most long-term care (LTC) is provided by family and friends. The purpose of the study was to determine the likelihood that expectations of care will be unmet at the onset of functional disability, and the factors that impact that likelihood.

Methods

Community-dwelling respondents from biannual repeated assessments (2006–2010) of the Health and Retirement Study over age 65 who expressed a caregiving expectation prior to need were included in the final analytical sample (n=1352). Logistic regression and change models were specified to address impact of variables on unmet expectations.

Results

Expectations of care were unmet for almost one-third (32%) of the sample, among whom 30% were not receiving needed care. Unmet expectations were associated with being unmarried, older and having a higher number of ADL deficits. Change over time in the number of predictor variables influenced the likelihood of unmet expectations.

Conclusions

Unplanned dependence on formal care systems and/or having unmet care needs places elders at risk of negative outcomes. Knowledge of factors that impact whether expected care is eventually received provides robust evidence for counselling individuals regarding the need to plan for additional LTC services.
Gunshot bullet embolisation in the middle cerebral artery
Authors: Sahin Sahatayi , Yakar F , Ozgural O , Caglar S
Published: December 2017

Bullet embolism (BE) is a rare phenomenon following a gunshot wound. A middle cerebral artery BE was detected in a 36-year-old male patient following a perforating left thoracic gunshot wound without obvious cranial injury. This paper discusses a case of BE in the cranial circulation in conjunction with a review of the relevant literature.
Real-time monitoring for structural health, public safety, and risk management of mine tailings dams
Authors: Hui Shiqiang (Rob) , Charlebois Lawrence , Sun Colin
Published: December 2017

Public awareness of tailings dam failures is increasing in the wake of incidents in Canada and abroad. The present work establishes the current state of practice in mine tailings dam monitoring and provides a summary of the current technical and operational gaps identified through industry and stakeholder engagement. These gaps may be addressed with currently available technologies supplied by commercial instrumentation manufacturers; however, the assumed costs and lack of regulatory demand may serve as barriers to adoption. An integrated approach and diverse suite of technologies is needed to address issues of dam stability, worker and public safety, and environmental protection. Technological applications and limitations are described and design requirements are proposed for an integrated, real-time monitoring system. Socio-economic impacts and loss reduction benefits are considered and the need for industry and regulator participation is emphasized.
Multipurpose use of side-scan sonar technology for fisheries science
Authors: Lucchetti Alessandro , Notti Emilio , Sala Antonello , Virgili Massimo
Published: December 2017

This study illustrates some potential applications of side-scan sonar to explain issues related to fisheries science. Side-scan sonar enabled identification of the footprint of different trawl types. It showed that a twin trawl sweeps a 30% greater area than a traditional trawl and that a semipelagic trawl door has more limited impact than a traditional bottom otter trawl. The side-scan sonar enabled detection and characterization of the interaction of trawl gear with the seafloor. It demonstrated the cod end is floating above the sea bottom during the tow, while the doors and clumps, sweeps and bridles have the most damaging effect on the seafloor. Side-scan sonar was used to assess the interaction between active and passive gear and between trawls and pipelines. It has been able to detect illegal fishing activity in marine protected areas and has been a valuable tool to resolve disputes between different sectors. Side-scan sonar was finally tested as a suitable tool for fish school detection and counting. Side-scan sonar emerged as a flexible tool to tackle rapidly a number of issues related to fishing impact, technology, and biology.
A Correction Method of a Binary Classifier Applied to Multi-Label Pairwise Models
Authors: Trajdos Pawel , Kurzynski Marek
Published: December 2017

In the paper, the problem of multi-label (ML) classification using the label-pairwise (LPW) scheme is addressed. For this approach, the method of correction of binary classifiers which constitute the LPW ensemble is proposed. The correction is based on a probabilistic (randomized) model of a classifier that assesses the local class-specific probabilities of correct classification and misclassification. These probabilities are determined using the original concepts of a randomized reference classifier (RRC) and a local soft confusion matrix. Additionally, two special cases that deal with imbalanced labels and double labeled instances are considered. The proposed methods were evaluated using 29 benchmark datasets. In order to assess the efficiency of the introduced models and the proposed correction scheme, they were compared against original binary classifiers working in the LPW ensemble. The comparison was performed using four different ML evaluation measures: macro and micro-averaged [Formula: see text] loss, zero-one loss and Hamming loss. Moreover, relations between classification quality and the characteristics of ML datasets such as average imbalance ratio or label density were investigated. The experimental study reveals that the correction approaches significantly outperform the reference method in terms of zero-one loss and Hamming loss.
A Smarr formula for charged black holes in nonlinear electrodynamics
Authors: Balart Leonardo , Fernando Sharmanthie
Published: December 2017

It is well known that the Smarr formula does not hold for black holes in nonlinear electrodynamics. The main reason for this is the fact that the trace of the energy–momentum tensor for nonlinear electrodynamics does not vanish as it is for Maxwell’s electrodynamics. Starting from the Komar integral, we derived a new Smarr-type formula for spherically symmetric static electrically charged black hole solutions in nonlinear electrodynamics. We show that this general formula is in agreement with some that are obtained for black hole solutions with nonlinear electrodynamics.
Cosmology with fermionic sources and relativistic fluid in Schutz’s formalism: Classical and quantum solutions
Authors: Ribas Marlos O. , Devecchi Fernando P. , Kremer Gilberto M.
Published: December 2017

In this work, a model for the pre-inflationary universe is developed where the sources of the gravitational field are a relativistic fluid and a self-interacting fermionic field. The inclusion of the relativistic fluid is based on Schutz’s model. From the classical analysis based on the Hamiltonian formalism, it is shown that the fluid degrees of freedom can be embodied by a conformal time variable and an expression for the scale factor as function of the conformal time is obtained. From the Wheeler–DeWitt equation, the expected value for the scale factor as function of the conformal time is determined. It is shown that contrary to the classical solution, the expected value of the scale factor does not have a singularity, since it is preceded by a contracted phase up to a minimum value from which the universe begins to expand. Furthermore, from the plots of the classical and quantum solutions for the scale factor as functions of the conformal time it is shown that a decoherence of the quantum solution occurs for late times and both solutions coincide.
Strongly coupled gauge theories: What can lattice calculations teach us?
Authors: Hasenfratz A. , Brower R. C. , Rebbi C. , Weinberg E. , Witzel O.
Published: December 2017

The dynamical origin of electroweak symmetry breaking is an open question with many possible theoretical explanations. Strongly coupled systems predicting the Higgs boson as a bound state of a new gauge-fermion interaction form one class of candidate models. Due to increased statistics, LHC run II will further constrain the phenomenologically viable models in the near future. In the meanwhile it is important to understand the general properties and specific features of the different competing models.

In this work we discuss many-flavor gauge-fermion systems that contain both massless (light) and massive fermions. The former provide Goldstone bosons and trigger electroweak symmetry breaking, while the latter indirectly influence the infrared dynamics. Numerical results reveal that such systems can exhibit a light [Formula: see text] isosinglet scalar, well separated from the rest of the spectrum. Further, when we set the scale via the vev of electroweak symmetry breaking, we predict a 2 TeV vector resonance which could be a generic feature of SU(3) gauge theories.
Analysis of the strong vertices of Σc∗ND and Σb∗NB in QCD sum rules
Authors: Yu Guo-Liang , Wang Zhi-Gang , Li Zhen-Yu
Published: December 2017

The strong coupling constants not only are important to understand the strong interactions of the heavy baryons, but can also help us reveal the nature and structure of these baryons. Additionally, researchers indeed have made great efforts to calculate some of the strong coupling constants, [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], etc. In this paper, we analyze the strong vertices [Formula: see text] and [Formula: see text] using the three-point QCD sum rules under the Dirac structure of [Formula: see text]. We perform our analysis by considering the contributions of the perturbative part and the condensate terms of [Formula: see text] and [Formula: see text]. After the form factors are calculated, they are then fitted into analytical functions which are used to get the strong coupling constants for these two vertices. The final results are [Formula: see text] and [Formula: see text].
Study on Underwater Sea Cucumber Rapid Locating Based on Morphological Opening Reconstruction and Max-Entropy Threshold Algorithm
Authors: Ge Luzhen , Gao Gaili , Yang Zhilun
Published: December 2017

In China, sea cucumber cultivation is developing rapidly, but sea cucumber catching still relies on inefficient manual work. Nowadays, the acquisition of underwater sea cucumber images and locating of sea cucumber target have provided technical support for underwater sea cucumber catching robots. However, there are still some problems to be solved, such as the degradation, edge blur and low contrast of underwater sea cucumber images due to the uneven light underwater and the absorption and scattering of light by water; and the cusp noises in the sea cucumber images produced by shells, gravers, planktons and other things in natural environment. Aiming at these problems, the underwater sea cucumber rapid locating method based on morphological opening reconstruction and max-entropy threshold algorithm (OR-META) is proposed in this paper. Firstly, the morphological opening reconstruction is adopted to smooth the original sea cucumber gray image; next, the max-entropy threshold segmentation algorithm is employed to segment the smoothed sea cucumber image, and the sea cucumber region in binary image is recognized according to area characteristics; finally, the position of sea cucumber region in the image is determined utilizing its centroid. In order to obtain the best result of sea cucumber image segmentation, three typical image segmentation algorithms OR-2DMETA, OR-OTSU and OR-2DOTSU are selected to compare with the OR-META. It is observed that the OR-META is obviously superior to the other three algorithms in qualitatively analyzing the image segmentation quality and quantitatively calculating the running time. To further analyze the image segmentation quality and locating accuracy, the images segmented by the OR-META are compared with manually segmented images. The comparison shows that although the image segmentation accuracy of the OR-META is low, with average target segmentation correct rate of 68.99%, the position of sea cucumber target in segmentation is predictable, which means that it will be within the directly drawn sea cucumber region. This demonstrates that the locating accuracy of the method is high. In addition, the method also has good real-time performance. It can be concluded from the experiment that for a RGB image with resolution ratio of 1280[Formula: see text][Formula: see text][Formula: see text]720 pixels, the average centroid Euclidean distance error of the OR-META segmented image is only 52.67 pixels, and its average running time is 0.6 s, which are qualified for the requirements of the sea cucumber catching robots.