bluuebunny/crossref_metadata_2025 huggingface dataset:
Air–fuel ratio control of lean‐burn SI engines using the LPV‐based fuzzy technique
Authors: Wu Hsiu‐Ming , Tafreshi Reza
Published: March 2018

Control of air–fuel ratio (AFR) plays a key role in the minimisation of the carbon dioxide and harmful pollutant emissions and maximisation of fuel economy. An inherent time‐varying delay existing in lean‐burn spark ignition (SI) engines is a major challenge for the AFR control. Herein an unstable internal dynamics with a parameter dependent system caused by time delay is established to represent a dominating feature of AFR. The proposed control scheme, LPV‐based fuzzy control technique, combines the features of LPV and fuzzy control to deal with the unstable internal dynamics of an AFR system with external disturbances and a high level of uncertainty in system parameters. Based on the desired error dynamics, an LPV dynamic error consisting of the unstable state and the AFR tracking error is determined. Subsequently, the proposed fuzzy control algorithm through a look‐up table is used to stabilise the LPV dynamic error. Then, the tracking error moves along the desired error dynamics towards zero. The system stability is assured via Lyapunov stability criteria. Finally, the simulation results demonstrate the effectiveness and robustness of the proposed control scheme under different operating conditions. Also, compared with the baseline controller, i.e. proportional–integral controller with Smith predictor, demonstrates its superiority.
Near-infrared scattering as a dust diagnostic
Authors: Saajasto Mika , Juvela Mika , Malinen Johanna
Published: March 2018

Context. Regarding the evolution of dust grains from diffuse regions of space to dense molecular cloud cores, many questions remain open. Scattering at near-infrared wavelengths, or “cloudshine”, can provide information on cloud structure, dust properties, and the radiation field that is complementary to mid-infrared “coreshine” and observations of dust emission at longer wavelengths.

Aims. We examine the possibility of using near-infrared scattering to constrain the local radiation field and the dust properties, the scattering and absorption efficiency, the size distribution of the grains, and the maximum grain size.

Methods. We use radiative transfer modelling to examine the constraints provided by the J, H, and K bands in combination with mid-infrared surface brightness at 3.6 μm. We use spherical one-dimensional and elliptical three-dimensional cloud models to study the observable effects of different grain size distributions with varying absorption and scattering properties. As an example, we analyse observations of a molecular cloud in Taurus, TMC-1N.

Results. The observed surface brightness ratios of the bands change when the dust properties are changed. However, even a change of ±10% in the surface brightness of one band changes the estimated power-law exponent of the size distribution γ by up to ~30% and the estimated strength of the radiation field KISRF by up to ~60%. The maximum grain size Amax and γ are always strongly anti-correlated. For example, overestimating the surface brightness by 10% changes the estimated radiation field strength by ~20% and the exponent of the size distribution by ~15%. The analysis of our synthetic observations indicates that the relative uncertainty of the parameter distributions are on average Amax, γ ~ 25%, and the deviation between the estimated and correct values ΔQ < 15%. For the TMC-1N observations, a maximum grain size Amax > 1.5μm and a size distribution with γ > 4.0 have high probability. The mass weighted average grain size is ⟨am⟩ = 0.113μm.

Conclusions. We show that scattered infrared light can be used to derive meaningful limits for the dust parameters. However, errors in the surface brightness data can result in considerable uncertainties on the derived parameters.
Intra- und postoperative Komplikationen klassifiziert nach Clavien Dindo bei Patienten > 80 J. nach transurethraler Resektion der Harnblase
Authors: Barakat Bara , Dawood Yousif , Horstmann Marcus
Published: March 2018

Einleitung Das Urothelkarzinom der Harnblase ist ein Tumor des höheren Lebensalters. Mit dem demografischen Wandel nimmt die Zahl sehr alter Patienten (> 80 J), die sich einer TUR-B unterziehen müssen, zu.

Material und Methoden In einer retrospektiven Analyse wurden die perioperativen Komplikationen von 89 Patienten > 80 Jahren, bei denen zwischen 2013 und 2016 an unserer Klinik eine TUR-B durchgeführt worden war, nach der Clavien Dindo-Klassifikation evaluiert.

Ergebnisse Das mittlere Patientenalter lag bei 87 J (82 – 94). 81 (91 %) Patienten waren unter oraler Antikoagulation (32 × ASS, 24 × NOAK, 25 × Marcumar). Histologisch wurde bei 25/89 (28 %) Patienten kein Tumor detektiert, bei 28/89 (31 %) ein pTa, bei 22/89 (25 %) ein pT1 und bei 14/89 (16 %) ein T2-Tumor oder höher detektiert. Insgesamt traten nach der Clavien Dindo-Klassifikation bei 36/89 (40 %) Patienten Komplikationen auf. Bei 21/89 (23 %) Patienten kam es zur prolongierten spülpflichtigen Makrohämaturie mit einer erneuten TUR-B bei 5/89 Patienten (6 %). 14 Patienten wurden transfundiert, 6 davon präoperativ. Nach Clavien Dindo wurden die Komplikationen bei 4/89 (4 %) Patienten als max. I, bei 21/89 (24 %) als max. II, bei 5/89 (6 %) Pat. als max. IIIb und bei 3/89 (3 %) als max. IVa gewertet. Drei (3 %) Patienten verstarben postoperativ (Clavien V): Ein Patient infolge einer Aspirationspneumonie (86 J, ASA IV), einer infolge einer Lungenembolie (90 J, ASA IV) und einer infolge eines Multiorganversagens (84, ASA III). In multivariaten Analysen bestätigte sich ein Tumorstadium > T2 als signifikanter Prädikator für das Auftreten von postoperativen Komplikationen (Odds Ratio von 9,54 (95 %CI 1,14 – 84,67; p = 0,032). Für die oralen Antikoagulantien ergab sich eine Odds Ratio von 4,10 (95 %CI, 41,00 – 1,23; p = 0,050).

Schlussfolgerung Insgesamt zeigen die Daten, dass die TUR-B bei Patienten > 80 J abhängig von vorliegenden Risikofaktoren mit einer erhöhten Komplikationsrate behaftet durchführbar ist. Prolongierte Makrohämaturie und die hohe Transfusionsrate sind v. a. auf den hohen Anteil oral antikoagulierter Patienten zurückzuführen.
Development of a hybrid molecular beam epitaxy deposition system for in situ surface x-ray studies
Authors: Andersen Tassie K. , Cook Seyoung , Benda Erika , Hong Hawoong , Marks Laurence D. , Fong Dillon D.
Published: March 2018

A portable metalorganic gas delivery system designed and constructed to interface with an existing molecular beam epitaxy chamber at beamline 33-ID-E of the Advanced Photon Source is described. This system offers the ability to perform in situ X-ray measurements of complex oxide growth via hybrid molecular beam epitaxy. The performance of the hybrid molecular beam epitaxy system while delivering metalorganic source materials is described. The high-energy X-ray scattering capabilities of the hybrid molecular beam epitaxy system are demonstrated both on oxide films grown solely from the metalorganic source and ABO3 oxide perovskites containing elements from both the metalorganic source and a traditional effusion cell.
Isotopic and spin-nuclear effects in solid hydrogens (Review Article)
Authors: Freiman Yuri A. , Crespo Yanier
Published: March 2018

The multiple isotopic family of hydrogens (H2, HD, D2, HT, DT, T2) due to large differences in the de Boer quantum parameter and inertia moments displays a diversity of pronounced quantum isotopic solid-state effects. The homonuclear members of this family (H2, D2, T2) due to the permutation symmetry are subjects of the constraints of quantum mechanics which link the possible rotational states of these molecules to their total nuclear spin giving rise to the existence of two spin-nuclear modifications, ortho- and parahydrogens, possessing substantially different properties. Consequently, hydrogen solids present an unique opportunity for studying both isotope and spin-nuclear effects. The rotational spectra of heteronuclear hydrogens (HD, HT, DT) are free from limitations imposed by the permutation symmetry. As a result, the ground state of these species in solid state is virtually degenerate. The most dramatic consequence of this fact is an effect similar to the Pomeranchuk effect in 3He which in the case of the solid heteronuclear hydrogens manifests itself as the reentrant broken symmetry phase transitions. In this review article we discuss thermodynamic and kinetic effects pertaining to different isotopic and spin-nuclear species, as well as problems that still remain to be solved.
Phonon excitations in the quasi-one-dimensional Haldane phase of SrNi2V2O8
Authors: Kurnosov V. , Gnezdilov V. , Lemmens P. , Pashkevich Yu. , Bera A. K. , Islam A. T. M. N. , Lake B.
Published: March 2018

Vibrational Raman spectra of a single crystal of the coupled Haldane chain compound SrNi2V2O8 with uniaxial anisotropy were investigated in the 10–1000 cm−1 frequency range at temperatures 7–300 K. No structural phase transition was observed. The number of phonon lines observed in the experiment and their intensity were analyzed on the basis of the local symmetry considerations of different structural complexes. This approach was successful in explaining the discrepancy between the numbers of expected and experimentally observed phonon lines. Closeness of a real arrangement of some structural units to higher symmetry than the Wyckoff position results in strong interferential quenching of a number of Raman lines in the spectra.
The effects of finite mass, adiabaticity, and isothermality in nonlinear plasma wave studies
Authors: Hellberg Manfred A. , Verheest Frank , Mace Richard L.
Published: March 2018

The propagation of arbitrary amplitude ion-acoustic solitons is investigated in a plasma containing cool adiabatic positive ions and hot electrons or negative ions. The latter can be described by polytropic pressure-density relations, both with or without the retention of inertial effects. For analytical tractability, the resulting Sagdeev pseudopotential needs to be expressed in terms of the hot negative species density, rather than the electrostatic potential. The inclusion of inertia is found to have no qualitative effect, but yields quantitative differences that vary monotonically with the mass ratio and the polytropic index. This result contrasts with results for analogous problems involving three species, where it was found that inertia could yield significant qualitative differences. Attention is also drawn to the fact that in the literature there are numerous papers in which species are assumed to behave adiabatically, where the isothermal assumption would be more appropriate. Such an assumption leads to quantitative errors and, in some instances, even qualitative gaps for “reverse polarity” solitons.
Double negative acoustic metastructure for attenuation of acoustic emissions
Authors: Kumar Sanjay , Bhushan Pulak , Prakash Om , Bhattacharya Shantanu
Published: March 2018

Acoustic metamaterials hold great potential for attenuation of low frequency acoustic emissions. However, a fundamental challenge is achieving high transmission loss over a broad frequency range. In this work, we report a double negative acoustic metastructure for absorption of low frequency acoustic emissions in an aircraft. This is achieved by utilizing a periodic array of hexagonal cells interconnected with a neck and mounted with an elastic membrane on both ends. An average transmission loss of 56 dB under 500 Hz and an overall absorption of over 48% have been realized experimentally. The negative mass density is derived from the dipolar resonances created as a result of the in-phase movement of the membranes. Further, the negative bulk modulus is ascribed to the combined effect of out-of-phase acceleration of the membranes and the Helmholtz resonator. The proposed metastructure enables absorption of low frequency acoustic emissions with improved functionality that is highly desirable for varied applications.
Distinct light emission from two-dimensional electron gas at a lattice-matched InAlN/AlGaN heterointerface
Authors: Li Lei , Hosomi Daiki , Miyachi Yuta , Miyoshi Makoto , Egawa Takashi
Published: March 2018

We report on distinct light emission from two-dimensional electron gas (2DEG) at a lattice-matched (LM) In0.12Al0.88N/Al0.21Ga0.79N heterointerface. The recombination between the electrons in the 2DEG in the ground state E1 and photoexcited holes in the Al0.21Ga0.79N layer was identified. In contrast to GaN channel-based heterostructures (HSs), larger activation energy of the 2DEG-related emission from LM In0.12Al0.88N/Al0.21Ga0.79N HS was obtained to be approximately 17 meV, which enables the distinguished 2DEG photoluminescence (PL) peak to be more thermally stable. Moreover, the existence of the 2DEG accelerates the reduction of the PL lifetime of the emission from Al0.21Ga0.79N. Compared to the general 2DEG PL feature with a broad recombination band in GaN channel-based HSs, the improved emission characteristics of the 2DEG in the In0.12Al0.88N/Al0.21Ga0.79N HS were attributed to electron localization in a deep triangular potential well, large 2DEG density induced by the In0.12Al0.88N layer, and the improvement of the interfacial crystal quality due to the lattice match between In0.12Al0.88N and Al0.21Ga0.79N layers. These findings provide important insight into understanding the InAlN-based HSs and will be potentially useful to advance the electronic and photonic applications for group-III nitrides.
Theory and data in diachronic Construction Grammar
Authors: Trousdale Graeme
Published: March 2018

Constructionalization (the diachronic creation of conventional symbolic units at different levels of schematicity and complexity) is a process which involves a series of micro-changes at different linguistic levels. The development of what with constructions in English is argued to be a case of grammatical constructionalization, whereby aspects of a construction become more general, productive, and less compositional. Equally, parts of the construction become more fixed (involving a reduction in variability), while other parts of the construction expand. The application of principles of construction grammar to aspects of diachronic change helps to clarify the relationship between theoretical principles of language change and the analysis of naturally occurring data; equally, the study of the what with construction reveals areas of potential convergence between formal and functional approaches to syntactic change, as well as areas of difference.
Cognitive explanations, distributional evidence, and diachrony
Authors: Cristofaro Sonia
Published: March 2018

Cognitively oriented approaches to the study of language standardly use synchronic distributional evidence to make assumptions both about the psychological mechanisms that lead speakers to create particular constructions, and about the components of a speaker’s mental representation of their language. Yet, as synchronic distributional patterns are a result of speciﬁc diachronic processes, any assumption about the psychological mechanisms or types of mental representation underlying particular patterns should take into account the diachronic processes that give rise to these patterns. Based on evidence from different languages and language families, the chapter discusses several diachronic processes pertaining to the development of various types of alignment systems and prototype effects in dependent clauses. It is shown that these processes provide no evidence for a number of assumptions about psychological mechanisms and a speaker’s mental representation that have been made on synchronic grounds in order to account for the relevant distributional patterns. It follows that this type of assumptions cannot be inferred directly from synchronic distributional patterns, and should be investigated independently of these patterns.
Smashing new results on aspectual framing
Authors: Matlock Teenie , Sparks David , Matthews Justin L. , Hunter Jeremy , Huette Stephanie
Published: March 2018

How do people describe events they have witnessed? What role does linguistic aspect play in this process? To provide answers to these questions, we conducted an experiment on aspectual framing. In our task, people were asked to view videotaped vehicular accidents and to describe what happened (perfective framing) or what was happening (imperfective framing). Our analyses of speech and gesture in retellings show that the form of aspect used in the question differentially influenced the way people conceptualized and described actions. Questions framed with imperfective aspect resulted in more motion verbs (e.g. driving), more reckless language (e.g. speeding), and more iconic gestures (e.g. path gesture away from the body to show travel direction) than did questions framed with perfective aspect. Our research contributes novel insights on aspect and the construal of events, and on the semantic potency of aspect in leading questions. The findings are consistent with core assumptions in cognitive linguistics, including the proposal that linguistic meaning, including grammatical meaning, is dynamic and grounded in perceptual and cognitive experience.
A near-infrared reflectance spectroscopic method for the direct analysis of several fodder-related chemical components in drumstick (Moringa oleifera Lam.) leaves
Authors: Zhang Junjie , Li Shuqi , Lin Mengfei , Yang Endian , Chen Xiaoyang
Published: March 2018

The drumstick tree has traditionally been used as foodstuff and fodder in several countries. Due to its high nutritional value and good biomass production, interest in this plant has increased in recent years. It has therefore become important to rapidly and accurately evaluate drumstick quality. In this study, we addressed the optimization of Near-infrared spectroscopy (NIRS) to analyze crude protein, crude fat, crude fiber, iron (Fe), and potassium (K) in a variety of drumstick accessions (N = 111) representing different populations, cultivation programs, and climates. Partial least-squares regression with internal cross-validation was used to evaluate the models and identify possible spectral outliers. The calibration statistics for these fodder-related chemical components suggest that NIRS can predict these parameters in a wide range of drumstick types with high accuracy. The NIRS calibration models developed in this study will be useful in predicting drumstick forage quality for these five quality parameters.
Chaperone complex formation of the transcription factor MalR involved in maltose utilization and amylolytic enzyme production in Aspergillus oryzae
Authors: Konno Yui , Suzuki Kuta , Tanaka Mizuki , Shintani Takahiro , Gomi Katsuya
Published: March 2018

The Zn2Cys6-type transcription factor MalR controls the expression of maltose-utilizing (MAL) cluster genes and the production of amylolytic enzymes in Aspergillus oryzae. In the present study, we demonstrated that MalR formed a complex with Hsp70 and Hsp90 chaperones under non-inducing conditions similar to the yeast counterpart Mal63 and that the complex was released from the chaperone complex after the addition of the inducer maltose. The MalR protein was constitutively localized in the nucleus and mutation in both the putative nuclear localization signals (NLSs) located in the zinc finger motif and the C-terminal region resulted in the loss of nuclear localization. This result indicated the involvement of NSLs in the MalR nuclear localization. However, mutation in both NLSs did not affect the dissociation mode of the MalR-Hsp70/Hsp90 complex, suggesting that MalR activation induced by maltose can occur regardless of its intracellular localization.
Autophagy balances mtDNA synthesis and degradation by DNA polymerase POLG during starvation
Authors: Medeiros Tânia Catarina , Thomas Ryan Lee , Ghillebert Ruben , Graef Martin
Published: March 2018

Mitochondria contain tens to thousands of copies of their own genome (mitochondrial DNA [mtDNA]), creating genetic redundancy capable of buffering mutations in mitochondrial genes essential for cellular function. However, the mechanisms regulating mtDNA copy number have been elusive. Here we found that DNA synthesis and degradation by mtDNA polymerase γ (POLG) dynamically controlled mtDNA copy number in starving yeast cells dependent on metabolic homeostasis provided by autophagy. Specifically, the continuous mtDNA synthesis by POLG in starving wild-type cells was inhibited by nucleotide insufficiency and elevated mitochondria-derived reactive oxygen species in the presence of autophagy dysfunction. Moreover, after prolonged starvation, 3′–5′ exonuclease–dependent mtDNA degradation by POLG adjusted the initially increasing mtDNA copy number in wild-type cells, but caused quantitative mtDNA instability and irreversible respiratory dysfunction in autophagy-deficient cells as a result of nucleotide limitations. In summary, our study reveals that mitochondria rely on the homeostatic functions of autophagy to balance synthetic and degradative modes of POLG, which control copy number dynamics and stability of the mitochondrial genome.
Simulations of particle and heat fluxes in an ELMy H-mode discharge on EAST using BOUT++ code
Authors: Wu Y B , Xia T Y , Zhong F C , Zheng Z , Liu J B
Published: March 2018

In order to study the distribution and evolution of the transient particle and heat fluxes during edge-localized mode (ELM) bursts on the Experimental Advanced Superconducting Tokamak (EAST), the BOUT++ six-field two-fluid model is used to simulate the pedestal collapse. The profiles from the EAST H-mode discharge #56129 are used as the initial conditions. Linear analysis shows that the resistive ballooning mode and drift-Alfven wave are two dominant instabilities for the equilibrium, and play important roles in driving ELMs. The evolution of the density profile and the growing process of the heat flux at divertor targets during the burst of ELMs are reproduced. The time evolution of the poloidal structures of T
e is well simulated, and the dominant mode in each stage of the ELM crash process is found. The studies show that during the nonlinear phase, the dominant mode is 5, and it changes to 0 when the nonlinear phase goes to saturation after the ELM crash. The time evolution of the radial electron heat flux, ion heat flux, and particle density flux at the outer midplane (OMP) are obtained, and the corresponding transport coefficients D
r, χ
ir, and χ
er reach maximum around 0.3 ∼ 0.5 m2 s−1 at ΨN = 0.9. The heat fluxes at outer target plates are several times larger than that at inner target plates, which is consistent with the experimental observations. The simulated profiles of ion saturation current density (j
s) at the lower outboard (LO) divertor target are compared to those of experiments by Langmuir probes. The profiles near the strike point are similar, and the peak values of j
s from simulation are very close to the measurements.
The Effects of Corpus Use on Second Language Vocabulary Learning: A Multilevel Meta-analysis
Authors: Lee Hansol , Warschauer Mark , Lee Jang Ho
Published: March 2018

This study investigates the effects of corpus use on second language (L2) vocabulary learning as well as the influence of moderators on effectiveness. Based on 29 studies representing 38 unique samples, all of which met several criteria for inclusion (e.g. with control groups), we found an overall positive medium-sized effect of corpus use on L2 vocabulary learning for both short-term (77 posttest effect sizes; Hedges’ g = 0.74, SE = 0.09, p < .001) and long-term periods (34 follow-up effect sizes; Hedges’ g = 0.64, SE = 0.17, p < .001). Furthermore, large variation in adjusted mean effect sizes across moderators was revealed. Above all, for the different dimensions of L2 vocabulary knowledge, in-depth knowledge (i.e. referential meanings as well as syntactic features of vocabulary) was associated with a large effect size. Moreover, the results revealed that learners’ L2 proficiency and several features of corpus use (i.e. interaction types, corpus types, training, and duration) influence the magnitude of the effectiveness of corpus use in improving L2 vocabulary learning.
NGSphy: phylogenomic simulation of next-generation sequencing data
Authors: Escalona Merly , Rocha Sara , Posada David
Published: March 2018

Motivation

Advances in sequencing technologies have made it feasible to obtain massive datasets for phylogenomic inference, often consisting of large numbers of loci from multiple species and individuals. The phylogenomic analysis of next-generation sequencing (NGS) data requires a complex computational pipeline where multiple technical and methodological decisions are necessary that can influence the final tree obtained, like those related to coverage, assembly, mapping, variant calling and/or phasing.

Results

To assess the influence of these variables we introduce NGSphy, an open-source tool for the simulation of Illumina reads/read counts obtained from haploid/diploid individual genomes with thousands of independent gene families evolving under a common species tree. In order to resemble real NGS experiments, NGSphy includes multiple options to model sequencing coverage (depth) heterogeneity across species, individuals and loci, including off-target or uncaptured loci. For comprehensive simulations covering multiple evolutionary scenarios, parameter values for the different replicates can be sampled from user-defined statistical distributions.

Availability and implementation

Source code, full documentation and tutorials including a ‘Getting started’ guide are available at http://github.com/merlyescalona/ngsphy

Supplementary information

Supplementary data are available at Bioinformatics online.
A Bayesian framework for multiple trait colocalization from summary association statistics
Authors: Giambartolomei Claudia , Zhenli Liu Jimmy , Zhang Wen , Hauberg Mads , Shi Huwenbo , Boocock James , Pickrell Joe , Jaffe Andrew E ,   The CommonMind Consortium, Pasaniuc Bogdan , Roussos Panos
Published: March 2018

Motivation

Most genetic variants implicated in complex diseases by genome-wide association studies (GWAS) are non-coding, making it challenging to understand the causative genes involved in disease. Integrating external information such as quantitative trait locus (QTL) mapping of molecular traits (e.g. expression, methylation) is a powerful approach to identify the subset of GWAS signals explained by regulatory effects. In particular, expression QTLs (eQTLs) help pinpoint the responsible gene among the GWAS regions that harbor many genes, while methylation QTLs (mQTLs) help identify the epigenetic mechanisms that impact gene expression which in turn affect disease risk. In this work, we propose multiple-trait-coloc (moloc), a Bayesian statistical framework that integrates GWAS summary data with multiple molecular QTL data to identify regulatory effects at GWAS risk loci.

Results

We applied moloc to schizophrenia (SCZ) and eQTL/mQTL data derived from human brain tissue and identified 52 candidate genes that influence SCZ through methylation. Our method can be applied to any GWAS and relevant functional data to help prioritize disease associated genes.

Availability and implementation: moloc is available for download as an R package (https://github.com/clagiamba/moloc). We also developed a web site to visualize the biological findings (icahn.mssm.edu/moloc). The browser allows searches by gene, methylation probe and scenario of interest.

Supplementary information

Supplementary data are available at Bioinformatics online.
Prolonged Detection of Zika Virus Nucleic Acid Among Symptomatic Pregnant Women: A Cohort Study
Authors: Lozier Matthew J , Rosenberg Eli S , Doyle Kate , Adams Laura , Klein Liore , Muñoz-Jordan Jorge , Alvarado Luisa I , Sharp Tyler M , Paz-Bailey Gabriela
Published: March 2018

A prospective cohort of women with reverse transcription polymerase chain reaction (RT-PCR) confirmed Zika virus infection aged 18–39 years in Puerto Rico found that pregnant women have about a 3-fold longer estimated median detection of Zika virus RNA in serum, which can increase definitive diagnosis of infection and facilitate timely and appropriate clinical management.
Functional Exploration of the Bacterial Type VI Secretion System in Mutualism: Azorhizobium caulinodans ORS571–Sesbania rostrata as a Research Model
Authors: Lin Hsiao-Han , Huang Hsin-Mei , Yu Manda , Lai Erh-Min , Chien Hsiao-Lin , Liu Chi-Te
Published: March 2018

The bacterial type VI secretion system (T6SS) has been considered the armed force of bacteria because it can deliver toxin effectors to prokaryotic or eukaryotic cells for survival and fitness. Although many legume symbiotic rhizobacteria encode T6SS in their genome, the biological function of T6SS in these bacteria is still unclear. To elucidate this issue, we used Azorhizobium caulinodans ORS571 and its symbiotic host Sesbania rostrata as our research model. By using T6SS gene deletion mutants, we found that T6SS provides A. caulinodans with better symbiotic competitiveness when coinfected with a T6SS-lacking strain, as demonstrated by two independent T6SS-deficient mutants. Meanwhile, the symbiotic effectiveness was not affected by T6SS because the nodule phenotype, nodule size, and nodule nitrogen-fixation ability did not differ between the T6SS mutants and the wild type when infected alone. Our data also suggest that under several lab culture conditions tested, A. caulinodans showed no T6SS-dependent interbacterial competition activity. Therefore, instead of being an antihost or antibacterial weapon of the bacterium, the T6SS in A. caulinodans ORS571 seems to participate specifically in symbiosis by increasing its symbiotic competitiveness.
Characterizing the Effect of Foliar Lipo-chitooligosaccharide Application on Sudden Death Syndrome and Sclerotinia Stem Rot in Soybean
Authors: Marburger David A. , Willbur Jaime F. , Weber Maria E. , Ané Jean-Michel , Kabbage Medhi , Conley Shawn P. , Smith Damon L.
Published: March 2018

Lipo-chitooligosaccharides (LCOs) are signal molecules produced by plant root endosymbionts and have been identified, formulated, and marketed as growth-promoting adjuvants for soybean (Glycine max [L.] Merr.). Experiments were conducted under controlled environmental conditions to characterize the effects of foliar LCO applications on early symptom development of sudden death syndrome (SDS), caused by Fusarium virguliforme, and Sclerotinia stem rot (SSR), caused by Sclerotinia sclerotiorum. Treatment factors for the SDS experiment included two soybean cultivars (Sloan and CH2105R2), two inoculation levels (noninoculated control and inoculated), and two LCO applications (control and foliar LCO application), whereas two experimental soybean lines (91-38 and 91-44) and two LCO applications (water control and foliar LCO application) were used in the SSR experiment. The LCO application did not significantly influence SDS root symptom severity or early-season growth characteristics. However, on the susceptible line (P = 0.01) and with LCO application (P = 0.03), significantly larger SSR lesions developed compared with the nontreated control and resistant line. These results suggest foliar-applied LCOs have a limited effect on early root symptom development caused by F. virguliforme but increase stem symptom development caused by S. sclerotiorum.
Incidence of Soybean vein necrosis virus in Alabama Soybean Fields
Authors: Sikora Edward J. , Conner Kassie N. , Jacobson Alana L.
Published: March 2018

Soybean vein necrosis virus (SVNV) was first reported in the United States during 2008 and has since rapidly spread to all major soybean-producing regions of North America. In 2013, a 4-year study was initiated to determine the distribution and incidence of the virus in Alabama soybean fields and potential weed hosts in the state. The weed host survey focused on populations of morning glory growing adjacent to maturing soybeans fields, along with additional commonly occurring weed species found in Alabama. SVNV was detected throughout Alabama (27 of 28 counties tested) and was most common in the northern region of the state. The average incidence of SVNV in fields in northern Alabama increased from 31.8% in 2013 to 82.6% in 2016. Average incidence of the virus in central Alabama soybean fields ranged from 5.1 to 14.8%, and southern Alabama fields ranged from 0 to 8.8% over the 3-year period. Only one population of morning glory tested positive for SVNV during the 3-year survey of this potential weed host. None of the 15 additional weed species screened tested positive for SVNV. This study has demonstrated that SVNV is found in Alabama soybean fields throughout the state and that soybeans grown in northern Alabama are at greater risk for infection.
First Report of Powdery Mildew Caused by Erysiphe aquilegiae on Columbine in the United States
Authors: Bradshaw Michael
Published: March 2018

Columbine (Aquilegia sp., Ranunculaceae) is a late summer to fall flowering ornamental. Powdery mildew was collected from columbine plants growing outdoors in the botanical garden at the Center for Urban Horticulture, University of Washington (47.65°N; 122.29°W) in October 2016. Morphological characteristics of the fungus were consistent with those of Erysiphe aquilegiae. To confirm species identification, the internal transcribed (ITS) region of rDNA was amplified with the primers ITS4/ITS6. E. aquilegiae (LC009944) was the most similar species with eight nucleotide differences (98.6% similarity). Based on morphological and molecular characteristics, it was concluded that the powdery mildew fungus was E. aquilegiae. To the author’s knowledge, this is the first unequivocal report of E. aquilegiae occurring within the United States. These results are important for the U.S. floral industry, for which Aquilegia is a major crop.
The Use of Serum Methadone/Metabolite Ratios to Monitor Changing Perinatal Pharmacokinetics
Authors: McCarthy John J. , Vasti Ernest J. , Leamon Martin H. , Graas Joseph , Ward Coburn , Fassbender Catherine
Published: March 2018

Objectives:

Pregnancy profoundly alters drug metabolism, accelerating clearance and confounding medication management, primarily through induction of CYP450 enzymes. Methadone is a CYP450 substrate with altered pharmacokinetics during pregnancy. We report on the use of serum methadone/metabolite ratios (MMRs) to monitor changes in methadone metabolism through the perinatal period and to objectively guide methadone dosing. Previous research found average MMRs in nonpregnant populations of between 11.3 and 12.7.

Methods:

Serum methadone and its major metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine concentrations were analyzed in 67 samples from 23 pregnant patients treated for opioid use disorder, and their calculated ratio was used to document changes in methadone clearance across trimesters and postpartum. Lower ratios indicate increased clearance.

Results:

The average MMR during pregnancy was 6.1. Ratios declined significantly from trimester 1 to trimester 3 (P = 0.007), and then rose significantly from trimester 3 to postpartum (P = 0.001). The per cent of ratios that were 4 or less, indicating ultrarapid metabolism, increased from 8% to 30% to 38% across trimesters, and decreased to 5% postpartum. Forty-four per cent of individual patients had at least 1 prepartum ratio of 4 or less.

Conclusions:

This study documents significant metabolic changes occurring perinatally, which indicate the need for both changes in methadone dose and dose frequency to maintain maternal/fetal stability, and also dose reductions as hypermetabolism reverses postpartum. MMRs provide an objective tool to more efficiently improve the safety and efficacy of methadone dosing perinatally.
Interprofessional Care and Teamwork in the ICU
Authors: Donovan Anne L. , Aldrich J. Matthew , Gross A. Kendall , Barchas Denise M. , Thornton Kevin C. , Schell-Chaple Hildy M. , Gropper Michael A. , Lipshutz Angela K. M.
Published: March 2018

Objectives:

We describe the importance of interprofessional care in modern critical care medicine. This review highlights the essential roles played by specific members of the interprofessional care team, including patients and family members, and discusses quality improvement initiatives that require interprofessional collaboration for success.

Data Sources:

Studies were identified through MEDLINE search using a variety of search phrases related to interprofessional care, critical care provider types, and quality improvement initiatives. Additional articles were identified through a review of the reference lists of identified articles.

Study Selection:

Original articles, review articles, and systematic reviews were considered.

Data Extraction:

Manuscripts were selected for inclusion based on expert opinion of well-designed or key studies and review articles.

Data Synthesis:

“Interprofessional care” refers to care provided by a team of healthcare professionals with overlapping expertise and an appreciation for the unique contribution of other team members as partners in achieving a common goal. A robust body of data supports improvement in patient-level outcomes when care is provided by an interprofessional team. Critical care nurses, advanced practice providers, pharmacists, respiratory care practitioners, rehabilitation specialists, dieticians, social workers, case managers, spiritual care providers, intensivists, and nonintensivist physicians each provide unique expertise and perspectives to patient care, and therefore play an important role in a team that must address the diverse needs of patients and families in the ICU. Engaging patients and families as partners in their healthcare is also critical. Many important ICU quality improvement initiatives require an interprofessional approach, including Awakening and Breathing Coordination, Delirium, Early Exercise/Mobility, and Family Empowerment bundle implementation, interprofessional rounding practices, unit-based quality improvement initiatives, Patient and Family Advisory Councils, end-of-life care, coordinated sedation awakening and spontaneous breathing trials, intrahospital transport, and transitions of care.

Conclusions:

A robust body of evidence supports an interprofessional approach as a key component in the provision of high-quality critical care to patients of increasing complexity and with increasingly diverse needs.
Obesity and the Risk of Colonic Diverticulosis: A Meta-analysis
Authors: Wijarnpreecha Karn , Ahuja Wasin , Chesdachai Supavit , Thongprayoon Charat , Jaruvongvanich Veeravich , Cheungpasitporn Wisit , Ungprasert Patompong
Published: March 2018

BACKGROUND:

The possible relationship between obesity and the risk of colonic diverticulosis has been suggested by recent epidemiologic studies, although the results were inconsistent.

OBJECTIVE:

This systematic review and meta-analysis was conducted to summarize all of the available data.

DATA SOURCES:

A comprehensive literature review was conducted using the MEDLINE and EMBASE databases through January 2017.

STUDY SELECTION:

Studies that compared the risk of colonic diverticulosis among subjects with obesity versus those without obesity were included.

MAIN OUTCOME MEASURES:

Effect estimates from each study were extracted and combined together using a random-effect, generic inverse variance method.

RESULTS:

Of 2989 potentially eligible articles, 10 studies (9 cross-sectional studies and 1 prospective cohort study) with 53,520 participants met the eligibility criteria and were included in the meta-analysis. The risk of colonic diverticulosis in obese subjects was significantly higher than in those without obesity, with a pooled OR of 1.41 (95% CI, 1.20–1.65). The statistical heterogeneity was high, with an I2 of 75%.

LIMITATIONS:

High statistical heterogeneity and publication bias in favor of positive studies may have been present in this meta-analysis.

CONCLUSIONS:

A significant association between colonic diverticulosis and obesity was shown in this study. However, additional studies are still required to determine the causality. See Video Abstract at http://links.lww.com/DCR/A500.
Overdoses and Substance Toxicity in Patients Admitted to Intensive Care Units in a Midwestern U.S. City
Authors: Schuring Craig A. , Dodge Daniel L. , Whitcomb Tyler J. , Wall Geoffrey C. , Smith Hayden L. , Hicklin Greg A.
Published: March 2018

Toxic exposures with serious outcomes have increased over the last decade. Limited data exists on the pattern and outcomes of overdose-exposure patients requiring intensive care unit (ICU) admission. The primary objective of this study was to characterize the causes, treatments, and outcomes of toxic exposures in a mid-sized Midwestern health system. The secondary objective was to report cumulative economic costs associated with these patients. Data were obtained from medical records of patients 18 years or older with a diagnosis code of overdose admitted to the ICU at 2 teaching hospitals between August 1, 2012, and July 31, 2014. There were 470 (10%) of the 4,495 total ICU admissions that met inclusion criteria during the study period. Average patient age was 39 (SD = 14.2) years, with 64% females. Intentional overdose exposure was the cause of 87% of admissions. The majority (70%) of exposures involved multiple pharmacological agents, including ethanol. Most patients did not require therapeutic maneuvers, nor used decontamination methods. Primary substance classes included analgesics, benzodiazepines, ethanol, selective serotonin reuptake inhibitor antidepressants, and methamphetamine. Two hundred sixty-five (56%) patients were ICU to direct home discharges, whereas 198 (42%) were transferred to a lower level of care. The mortality rate in the sample was 1%. Average hospital charges per admission were $20,375 and average ICU charges were $5,284, which summed to more than $2 million in total charges. Causes, treatments, and outcomes of toxic exposures admitted to the ICU in a mid-sized Midwestern city reveal a potential ICU burden. Financial health care costs associated with these toxic exposures were substantial. Greater public health efforts are needed to attempt to minimize preventable admissions and better understand antecedents.
Community-Based Academic Level I Trauma Center Prepares for the 2016 Republican National Convention
Authors: Keefe Judy , Cern Kathy , Wiita Sharon , Raubenolt Amy , Atkins Elizabeth
Published: March 2018

Disaster preparedness has come to the forefront for hospitals since the 9/11 attacks in 2001. Many improvements have been made in emergency management and planning for catastrophic events. Both urban and community hospitals have the same responsibilities and commitments to their patients and communities. When the announcement was made that the 2016 Republican National Convention was going to be held in Cleveland, OH, Cleveland Clinic Akron General (CCAG) had to be confident in its abilities to handle any situation that might arise not just as a community hospital but also as a Level I trauma center. Organizing and preparing for more than a year, CCAG developed a detailed and well-thought-out preparedness program, with senior leadership implementing a clear chain of command. Developing and maintaining a strong and steady defense through detailed preparation, communication, teamwork, and organization are the keys to success.
Trauma Providers' Knowledge, Views, and Practice of Trauma-Informed Care
Authors: Bruce Marta M. , Kassam-Adams Nancy , Rogers Mary , Anderson Karen M. , Sluys Kerstin Prignitz , Richmond Therese S.
Published: March 2018

Trauma-informed interventions have been implemented in various settings, but trauma-informed care (TIC) has not been widely incorporated into the treatment of adult patients with traumatic injuries. The purpose of this study was to examine health care provider knowledge, attitudes, practices, competence, and perceived barriers to implementation of TIC. This cross-sectional study used an anonymous web-based survey to assess attitudes, knowledge, perceived competence, and practice of TIC among trauma providers from an urban academic medical center with a regional resource trauma center. Providers (nurses, physicians, therapists [physical, occupational, respiratory]) working in trauma resuscitation, trauma critical care, and trauma care units were recruited. Descriptive statistics summarized knowledge, attitudes, practice, competence, and perceived barriers to TIC and logistic regression analyses examined factors predicting the use of TIC in practice. Of 147 participants, the majority were nurses (65%), followed by therapists (18%) and physicians (17%), with a median 3 years of experience; 75% answered the knowledge items correctly and 89% held favorable opinions about TIC. Nineteen percent rated themselves as less than “somewhat competent.” All participants rated the following as significant barriers to providing basic TIC: time constraints, need of training, confusing information about TIC, and worry about retraumatizing patients. Self-rated competence was the most consistent predictor of providers' reported use of specific TIC practices. Despite some variability, providers were generally knowledgeable and held favorable views toward incorporating TIC into their practice. TIC training for trauma providers is needed and should aim to build providers' perceived competence in providing TIC.
Update in adrenal venous sampling for primary aldosteronism
Authors: Rossi Gian Paolo
Published: March 2018

Purpose of review

Current guidelines recommend adrenal venous sampling (AVS) to identify the surgically curable causes of hyperaldosteronism. In contrast with this recommendation, AVS remains markedly underutilized in clinical practice, which leads to deny curative adrenalectomy, to many patients with primary aldosteronism. The purpose of this review is to challenge the views that AVS is a technically challenging, invasive and risky procedure, which moreover, is difficult to interpret.

Recent findings

Several studies, including a large international survey on how AVS is being performed and used at major referral centres worldwide the AVIS-1 Study – and a randomized clinical trial comparing and AVS and a computed tomography based strategy, will be examined.

The results of these studies have sound implications for clinical practice in that they allow to define what to do and what not to do for proper performance and interpretation of AVS and avoidance of the main concern, for example the risk of adrenal vein rupture.