bluuebunny/crossref_metadata_2025 huggingface dataset:
Cicerón y Agustín. A propósito de la república
Authors: Sánchez Barbosa Diana Marcela
Published: September 2019

Para Agustín, la paz es uno de los mayores bienes tanto de la vida eterna, como de la temporal. Sin embargo, solo en la primera se presenta en forma definitiva, en la segunda es un bien dudoso e incierto. Esta afirmación cobra sentido si se tiene en cuenta que en el orden de lo creado, lo temporal, está mediado por el pecado original. Ahora bien, podría considerarse que la paz y el orden son exclusivos de la vida eterna, pero no es así, pues en la vida terrena sería imposible la existencia y el progreso de la humanidad sin la presencia de dichos elementos. De esta manera, en este escrito se intenta mostrar cómo, a pesar de que Agustín critica la figura de la república tal como la plantea Cicerón, ve en ella el elemento que posibilita y determina la paz en la tierra.
Tiempo, eternidad y distentio animi. Una clave de lectura del libro XI de Confesiones
Authors: Triviño Cuellar Jonathan
Published: September 2019

En la reflexión agustiniana, el análisis del tiempo deriva de su condición misma de creatura; por esta razón, el tiempo resulta ser como es, es decir, resulta tener esa precariedad ontológica que comparte con todo lo creado. Cuando preguntamos por el tiempo, descubrimos que esta realidad no es algo más que nuestro entendimiento pueda abordar a la manera como se toma un objeto desconocido, sino que esta noción se nos revela como una dimensión de nuestro ser. En presente artículo propongo una clave de interpretación del libro XI de Confesiones en el cual muestro la importancia de presentar el sentido de la existencia temporal de cara al Creador eterno, así como propongo una interpretación de la dimensión doble, positiva y negativa, de la distentio animi.
Gobierno, ilustración y violencia: una mirada a la “transición política” en Colombia desde el proyecto “atemperado” de la emancipación
Authors: Ballén Rodríguez Juan Sebastián
Published: September 2019

Uno de los trabajos menores que a la vez se ha inmortalizado entre los ensayos más citados en los cursos de historia de la filosofía es la publicación de 1784 titulada Respuesta a la pregunta: ¿Qué es la ilustración? del filósofo alemán Immanuel Kant. Proponemos a continuación una hermenéutica de los principales tópicos y problemas que aborda Kant en este texto fundamental, que conectaremos, adicionalmente, con la tesis que se sustentará en este trabajo, a saber: que la filosofía moderna es un ejercicio de crítica del pensamiento que tiene implicaciones tanto en las miradas educativas como en las apuestas éticas y políticas que procuran encontrar salidas para una sociedad atravesada históricamente por el conflicto armado (como sucede en el caso colombiano), en un escenario complejo donde confluyen crisis económicas y luchas asimétricas y fratricidas a través de las cuales se ha buscado, de forma convencional y no convencional, la obtención del poder político.
¿Somos lo que compramos? Intercambios entre Bauman y Žižek en torno al concepto de sujeto de consumo
Authors: Pineda Repizo Adryan Fabrizio
Published: September 2019

Este artículo presenta una reflexión en torno al lugar de la subjetividad en la sociedad de consumidores, poniendo en discusión dos alternativas: por una parte, la tesis de la identificación entre sujeto y mercancía, rastreable, entre otros, en Bauman, y, por otra parte, la interpretación de Žižek de la subjetividad como un excedente emergente del conflicto con el orden simbólico. El intercambio resultante entre estas alternativas muestra las relaciones constitutivas del sujeto de consumo en la dimensión del deseo, en el margen de la libertad y en el papel de la reflexividad. Finalmente, se plantea la comprensión de la relación entre el sujeto y el mundo material como una performatividad constructiva de la subjetividad.
Prediction of the Flow Response of a Turbulent Flame to Acoustic Pertubations Based on Mean Flow Resolvent Analysis
Authors: Kaiser Thomas Ludwig , Lesshafft Lutz , Oberleithner Kilian
Published: September 2019

Resolvent analysis is applied to a nonreacting and a reacting swirled jet flow. Time-averaged flows as input for the resolvent analysis and validation for the results of the resolvent analysis are obtained by experiments. We show that in the nonreacting (cold) flow case, the resolvent analysis is capable of predicting the hydrodynamic response to upstream harmonic acoustic forcing if the flow shows low-rank behavior. This is the case for low and moderate acoustic forcing amplitudes. Even for very strong acoustic velocity amplitudes that are of the same order of magnitude as the flow velocity, the resolvent analysis still provides reasonable results. The method also yields very good results for the reacting flow in terms of velocity fluctuation and heat release response to the acoustic forcing. This confirms the idea that the resolvent method could be applied to estimate the flame transfer function (FTF) based on the mean flow and flame.
Experimental Study of the Precessing Vortex Core Impact on the Liquid Fuel Spray in a Gas Turbine Model Combustor
Authors: Renaud Antoine , Ducruix Sébastien , Zimmer Laurent
Published: September 2019

Despite being good candidates for the reduction of pollutant emissions from gas turbines, burners operating in lean premixed prevaporized regimes often face stability issues and can be sensitive to perturbations. The swirling flow used to aerodynamically stabilize the flame can also lead to the appearance of a large-scale coherent flow structure known as the precessing vortex core (PVC). In this study, a swirl-stabilized combustor fed with liquid dodecane is studied at a globally lean operating condition with the help of high-speed diagnostics and dynamic mode decomposition (DMD) as the main postprocessing method. It is shown that the trace of a PVC originating inside the injector is still present in the fuel spray at the entrance of the chamber even though the aerodynamical structure itself is not detectable anymore. The perturbation of the fuel spray is then transmitted to the flame through local equivalence ratio fluctuations. It is observed that the PVC trace on the spray and thus on the flame can be suppressed by air flow modulations generated by a siren device. The suppression of this trace is shown to come from a decay of the aerodynamical structure itself rather than by a change in fuel mixing or vaporization. Analysis of the characteristic frequency of the PVC shows a frequency spread indicating a loss of coherence of the structure with the high-amplitude air flow rate fluctuations.
Theoretical Modeling on Monitoring Left Ventricle Deformation Using Conformal Piezoelectric Sensors
Authors: Zhang Yangyang , Lü Chaofeng , Lu Bingwei , Feng Xue , Wang Ji
Published: September 2019

Left ventricular (LV) volume is a crucial indicator for the assessment of the heart function. However, the current clinical practice cannot be used to monitor the LV volume continuously or warn patients with high risk in time before heart attack occurs in everyday life, resulting in high mortality and morbidity. Here, we theoretically validate the potentiality of a conformal real-time LV deformation-monitoring sensor using piezoelectric materials. The electromechanical relationship between the deformation of the hearts and output voltage signals of the sensors is demonstrated first. End-to-end displacements and deformations of piezoelectric films under cyclic load are derived from the output voltage signals and then compared with experimental values. Then, the real-time LV volumes of a pig and a cow are derived and compared by employing the experimental output voltage signals of the flexible sensor mounted on the LV surface. Finally, by employing the LV volume data of healthy people and patients with various heart diseases in the literature, the theoretical output voltage signals of flexile sensors when mounted on LV surface are calculated and compared. These predicted output voltage signals show significant differences for people with different kinds of cardiac diseases. The results in this study demonstrate that the conformal piezoelectric sensor is fully potential to continuously monitor the cardiac deformation and correspondingly provide timely warning for cardiologists and patients with heart diseases.
Biological parameters of Neoseiulus longilaterus (Athias-Henriot) (Parasitiformes, Phytoseiidae) fed on prey and pollen in laboratory conditions

Authors: Tsolakis Haralabos , Sinacori M. , Ragusa E. , Lombardo A.
Published: September 2019

Tetranychus urticae is the most important pest on different crops worldwide. Search for endemic phytoseiid mites co-occurring with the above pest, which might be good candidates as biocontrol agents, represents the policy followed by most scientists in recent years. The aim of the present work was to assess the various biological and demographic parameters of Neoseiulus longilaterus, associated with T. urticae on weeds, in laboratory conditions using the latter tetranychid and pollen of Oxalis pes-caprae as food. The results showed a better performance of the predator on the prey as regards the postembryonic development (7.63 and 8.18 days for prey and pollen respectively) and the demographic parameters (rm 0.158 and 0.102, Ro 26.89 and 18.76, DT 4.39 and 6.78 for T. urticae and Oxalis respectively). Our data shows that N. longilaterus have similar traits with some phytoseiid species belonging to type II selective predators, but also with some others included within type III generalist predators. As a matter of fact, it can be considered an interesting biocontrol agent towards T. urticae, able also to develop on alternative foods as the pollen of Oxalis.
Oribatid mites (Acari, Oribatida) inhabiting termite nests in the Faan Meintjes Nature Reserve (South Africa)

Authors: Ermilov Sergey G. , Hugo-Coetzee Elizabeth A. , Khaustov Alexander A. , Theron Pieter D.
Published: September 2019

The present study is based on oribatid mite material (Acari, Oribatida) collected from nests of the termite Trinervitermes trinervoides(Isoptera, Termitidae) of the Faan Meintjes Nature The present study is based on oribatid mite material (Acari, Oribatida) collected from nests of the termite Trinervitermes trinervoides (Sjöstedt, 1911) (Isoptera, Termitidae) of the Faan Meintjes Nature Reserve in South Africa. A list of identified taxa, including nine species, eight genera and seven families, is presented. One new species is described; Saltatrichus louiseae sp. nov. (Zetomotrichidae) differs from all species of the genus by the long, thick interlamellar setae and setiform setae ft” on leg tarsi IV. Bipassalozetes bidactylus (Coggi, 1900) is recorded in the fauna of South Africa for the first time. The five species with the highest abundance and occurrence in nests were Coetzeella navalensis Ermilov, Hugo-Coetzee & Khaustov, 2017, B. bidactylus, S. louiseae sp. nov., Ausoribula bloemfonteinensis Ermilov, Hugo-Coetzee & Khaustov, 2017 and Transoribates agricola (Nakamura & Aoki, 1989). Remarks on variations of B. bidactylus and C. navalensis are given.
Measurements and modeling of acoustic propagation in a scale model canyon
Authors: Ballard Megan S. , Sagers Jason D.
Published: September 2019

Two scale-model acoustic propagation experiments were conducted in a laboratory tank to investigate three-dimensional (3D) propagation effects induced by range-dependent bathymetry. The model bathymetry, patterned after measured bathymetric data, represents a portion of the Hudson Canyon at 1:7500 scale. The bottom condition in the scale model is nearly pressure release, and as a result, the bottom reflection and backscattering are stronger than that of the real ocean environment. Measurements are presented for propagation paths oriented along and across the axis of the canyon. The measured data are interpreted using both 3D adiabatic-mode and 3D ray models. For propagation along the canyon axis, horizontal focusing is observed, and the out-of-plane arrivals are identified using the vertical mode/horizontal ray analogy to determine which wall or walls of the canyon refracted the sound. For the across-canyon propagation, out-of-plane arrivals are observed for both forward scattered and backward scattered sound. Using the 3D ray model, an investigation of the horizontal and vertical launch angles is used to identify features on the canyon walls responsible for the measured out-of-plane propagation. For both the along- and across-canyon experiments, the 3D ray model produced a solution that was more accurate and less computationally intensive.
Method of numerical Green's function determination for far-field scattering solutions from objects at a water-sediment interface
Authors: Gunderson Aaron M. , Isakson Marcia J. , Bonomo Anthony L.
Published: September 2019

A method is presented for numerically determining Green's functions for the purpose of calculating the far-field scattering from objects resting on or buried within the seafloor. To obtain the far-field scattering, initial evaluation of the three-dimensional near-field solution is required, through finite element analysis or other means. The Green's function and its spatial derivatives are then numerically evaluated for input into the Helmholtz-Kirchhoff integral, yielding the far-field scattering solution. This numerical technique determines the Green's function directly and avoids requiring analytic forms of Green's functions, which may be difficult or time consuming to evaluate for complex environments. This paper demonstrates the effectiveness of applying the numerical Green's function determination technique in conjunction with near-field results from finite element models to determine the far-field scattering for various elastic targets in free-field and flat seafloor environments. The method may be generalizable to arbitrary targets at complicated interfaces, incorporating interface roughness, layering, and volume inhomogeneities.
Source triangulation utilizing three-dimensional arrivals: Application to the search for the ARA San Juan submarine
Authors: Dall'Osto David R.
Published: September 2019

On Nov. 15, 2017, an intense acoustic event coincident with the disappearance of the Argentine navy submarine, ARA (Armada Argentina) San Juan, was recorded on the hydroacoustic network established to enforce compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Analysis by Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) scientists, based on two hydroacoustic and one seismic detection, provided a likely origin within an error ellipse of 19 km by 12 km; analysis based solely on the main arrival detected at the two hydroacoustic stations gave an error ellipse of ∼500 km by ∼25 km [Nielsen, Zampolli, Le Bras, Mialle, Bittner, Poplavskiy, Rozhkov, Haralabus, Tomuta, Bell, and Grenard, in European Geosciences Union General Assembly, Vol. 20, EGU2018-18559 (2018)]. The large major axis depends on uncertainty in establishing the event time, while the minor axis depends on precision in the ocean state estimate used to model propagation speed. This paper demonstrates how three-dimensional (3-D) propagation features can also be used in source triangulation, in particular when no seismic detection is available. A mode-based 3-D propagation model is implemented to reconstruct the propagation path of a 3-D arrival bathymetrically refracted from the continental slope. This additional arrival provides a third (virtual) station to decouple the location and time of the event and triangulate the event. This improvement is commensurate with the CTBTO analysis, but does not rely on the additional seismic station detection.
Beam tracing for two- and three-dimensional problems in ocean acoustics
Authors: Porter Michael B.
Published: September 2019

Beam tracing is an extension of ray tracing that constructs beams around the central rays radiating from a source. Typically, a fan of such beams is used to represent a point source and the field at any given location is computed by coherently summing all contributing beams. On a slightly superficial level, one points to the following key benefits: (1) improved accuracy because the beams smooth out singularities of the ray-theoretic field, and (2) algorithmic advantages because eigenrays precisely connecting the source and the receiver do not need to be identified. One may argue about these considerations; however, beam tracing methods have emerged as a very important class of methods for computing ocean acoustic fields. Interestingly, the published literature has not kept up with the numerous advances in beam tracing, including algorithmic developments that are important to efficient and robust implementations. Furthermore, there are quite a few variants of beam tracing algorithms with very different characteristics. This article discusses these variants, significant advances in practical implementation, and performance characteristics.
Scale model observations of coupled vertical modes in a translationally invariant wedge
Authors: Sagers Jason D. , Ballard Megan S.
Published: September 2019

Scale-model tank experiments offer a controlled environment in which to make underwater acoustic propagation measurements that can provide high-quality data for comparison with numerical models. This paper presents results from a scale model experiment for a translationally invariant wedge with a 10° slope fabricated from closed-cell polyurethane foam to investigate three-dimensional (3-D) propagation effects. A computer controlled positioning system accurately located a receiving hydrophone in 3-D space to create a dense field of synthetic vertical line arrays, which are subsequently used to mode filter the measured pressure field. The resulting mode amplitudes show the modal propagation zone, the modal shadow zone, and the classical intra-mode interference pattern resulting from rays launched up and along the slope. The observed features of the measured data are compared to three different propagation models: an exact, closed-form solution for a point source in wedge with pressure release boundaries, a 3-D ray trace model, and an adiabatic model. Examination of the mode amplitudes produced by the models reveals how the effects of vertical mode coupling can be observed in the measured data.
Effects of front width on acoustic ducting by a continuous curved front over a sloping bottom
Authors: DeCourcy Brendan J. , Lin Ying-Tsong , Siegmann William L.
Published: September 2019

The behavior of sound near an ocean front in a region with wedge bathymetry is examined. The front is parameterized as a zone of variation with inshore and offshore boundaries parallel to a straight coastline. The importance of frontal width and frontal sound speed on the ducting of acoustic energy is examined. Previous analytical studies of sound propagation and parameter sensitivity in an idealized wedge environment use an unphysical but convenient single interface front representation, which is here replaced by a continuous sound speed profile. The continuous profile selected is convenient for analytical investigation, but encourages the use of asymptotic approximation methods which are also described. The analytical solution method is outlined, and numerical results are produced with an emphasis on comparing to the single interface front. These comparisons are made to highlight the strengths and weaknesses of the idealized model for capturing the horizontal ducting effects.
Three-dimensional Cartesian parabolic equation model with higher-order cross-terms using operator splitting, rational filtering, and split-step Padé algorithm
Authors: Lee Keunhwa , Seong Woojae , Na Youngnam
Published: September 2019

An approximate form of three-dimensional Cartesian split-step marching solution for the acoustic parabolic equation is derived in order to obtain the efficient algorithm for sound propagation in the three-dimensional ocean. The operator splitting method is used to split the full exponential operator into three exponential operators for depth, cross-range, and the combination of the two. The first two terms are implemented with the split-step Padé algorithm and the final term is implemented with the Taylor series expansion in depth and cross-range operator. In order to resolve the divergence of Taylor approximation out of the interval of convergence, the rational filter of rectangular type is applied to the depth and cross-range operator. The use of the filter improves the stability of the solution but requires extra numerical burdens. Numerical issues involving the accuracy, efficiency, and stability of the proposed model are discussed and illustrated in an ocean wedge environment.
Observation of out-of-plane ambient noise on two vector sensor moorings in Lake Travis
Authors: Sagers Jason D. , Lenhart Richard D. , Ballard Megan S.
Published: September 2019

Two Autonomous Underwater Multi-Dimensional Acoustic Recorders (AUMDAR) were deployed in the southeastern part of Lake Travis during the summer of 2018. Each AUMDAR system possessed a three-axis acoustic vector sensor capable of estimating the azimuthal and vertical arrival angles from discrete sound sources. A unique and complicated propagation environment existed during the experiment due to the mooring locations and the range-dependent lake bathymetry. The AUMDAR systems were almost entirely shielded from sound emanating from surface vessels to the south and southeast of the deployment location, while a larger, yet limited, direct acoustical field of view was realized to the north and northeast. During the evening hours, the low-frequency received level increased without a corresponding increase in the number of detected discrete surface vessels. During the same time, the predominant direction of the received sound pointed toward the bend in the river channel. A three-dimensional ray model was employed to assess the various arrival angles from a grid of source positions located throughout the lake. The model results are consistent with the observations and suggest that the ambient noise field originated from vessels physically located to the northwest of the sensors, but arriving at angles consistent with out-of-plane sound propagation.
Asymptotic solution for the problem of sound propagation in a shallow sea with the bathymetry described by a parametric quadratic function
Authors: Petrov Petr N. , Petrov Pavel S.
Published: September 2019

A wide class of three-dimensional sound propagation problems in shallow water where the bathymetry can be locally approximated by a parametric quadratic function is considered. Relevant examples of such bathymetry functions include underwater canyons and ridges. Asymptotic solution for this class of problems is derived under the adiabaticity assumption. The solution is based on mode parabolic equation theory and group-theoretical disentanglement formulas for operator exponentials. Two examples are considered (a ridge and a bottom with quadratic slope), and respective wavefront geometry is studied.
Three-dimensional finite element simulation of acoustic propagation in spiral bubble net of humpback whale
Authors: Qing Xin , White Paul R. , Leighton Timothy G. , Liu Songzuo , Qiao Gang , Zhang Yu
Published: September 2019

In 2004, Leighton hypothesized that the acoustic calls emitted by humpback whales when feeding using bubble nets, may enhance the effectiveness of the net in confining prey (such as herring) by forming a “wall of sound” with a quiet zone within. Modelling of the acoustics of this phenomenon was previously restricted to 2D; this paper conducts a 3D model of the propagation of signals resembling those emitted by humpback whales when bubble netting, projected into an upward spiral bubble net which data to date suggest is the accurate form for the bubble net in 3D space. In this study, the feeding calls were analyzed in the time-frequency domain to extract acoustic information sufficient to allow modeling of the resulting spatial distribution of acoustic pressure and particle velocity, and how they vary over the duration of the call. Sound propagation in the bubble net was described by using a linear steady-state formulation for an effective medium of bubbly water. Using the predicted attenuation, phase velocity and density in bubbly water, a 3D finite element model was constructed to numerically simulate the upward-spiral bubble net which consists of a mixture of bubbles that exhibit a range of radii. The acoustic pressure field and particle motion field were both calculated within the bubble net. The simulation results show that the energy of the whale feeding call could be effectively focused in the bubble net, generating intensive sound pressure and particle motion fields in the bubbly arm of the net, but with some “quiet” regions closer to the center of the net, as Leighton hypothesized. Furthermore, when the hearing ability of herring is taken into consideration, the results suggest that this acoustic focusing effect could be a plausible factor in trapping them in the bubble net. It also allows speculation on the possible enhancements that the time-varying nature of the call during feeding could give to the whale in this mechanism for the bubble net feeding by humpback whales.
Three-dimensional boundary fitted parabolic-equation model of underwater sound propagation
Authors: Lin Ying-Tsong
Published: September 2019

A three-dimensional (3-D) parabolic-equation (PE) method utilizing a higher-order split-step Padé algorithm and a boundary fitted grid has been developed to accurately solve 3-D underwater sound propagation problems with non-planar or tilted boundaries. At each PE marching step, the split-step Padé algorithm enables the method of alternating directions to implement the square-root Helmholtz operator by carrying out its one-dimensional (1-D) derivative components alternately, and it also allows a straightforward application of the 1-D non-uniform Galerkin method to discretize the solution mesh. The advantage of the boundary fitted grid to improve PE solution accuracy is most profound in the case of fitting to a pressure release surface as its boundary condition is a scalar and has no direction. This method can also be applied to a sloping interface by rotating the grid to align with the interface. Numerical problems of semi-circular waveguide and tilted wedge were solved using this boundary fitted PE method, and benchmark reference solutions were used to examine and confirm the accuracy of the PE solutions. Future applications include modeling 3-D acoustic scattering from a rough sea surface and 3-D sound propagation in beach environments.
Environmental information content of ocean ambient noise
Authors: Siderius Martin , Gebbie John
Published: September 2019

In recent years, methods have been developed to estimate a variety of environmental parameters based on measurements of the ocean ambient noise. For example, noise has been used to estimate water depth using the passive fathometer technique and bottom loss estimated and used to invert for seabed parameters. There is also information in the noise about the water column sound speed, volume attenuation, and the sea-state. The Fisher information can be used to quantify the basic information available in the noise measurements and its inverse, the Cramér–Rao lower bound (CRLB), provides the lower limit on the variance of an unbiased estimator of a particular parameter. The CRLB can be used to study the feasibility of various measurement configurations and parameter sensitivities. In this paper, the CRLB is developed for ocean ambient noise and the environmental information contained in the measurements is determined. The CRLBs provide an estimate of the underlying information in the data, however, it is independent of the estimation methodology. This is useful to determine if a given estimation method is reaching the lower bound. Results illustrating the bounds as well as sensitivities and performance of estimators are demonstrated using both simulations and data.
Visualizing the Complexity of the Athlete-Monitoring Cycle Through Principal-Component Analysis
Authors: Weaving Dan , Beggs Clive , Dalton-Barron Nicholas , Jones Ben , Abt Grant
Published: September 2019

Purpose: To discuss the use of principal-component analysis (PCA) as a dimension-reduction and visualization tool to assist in decision making and communication when analyzing complex multivariate data sets associated with the training of athletes. Conclusions: Using PCA, it is possible to transform a data matrix into a set of orthogonal composite variables called principal components (PCs), with each PC being a linear weighted combination of the observed variables and with all PCs uncorrelated to each other. The benefit of transforming the data using PCA is that the first few PCs generally capture the majority of the information (ie, variance) contained in the observed data, with the first PC accounting for the highest amount of variance and each subsequent PC capturing less of the total information. Consequently, through PCA, it is possible to visualize complex data sets containing multiple variables on simple 2D scatterplots without any great loss of information, thereby making it much easier to convey complex information to coaches. In the future, athlete-monitoring companies should integrate PCA into their client packages to better support practitioners trying to overcome the challenges associated with multivariate data analysis and interpretation. In the interim, the authors present here an overview of PCA and associated R code to assist practitioners working in the field to integrate PCA into their athlete-monitoring process.
Relationships Among PlayerLoad, High-Intensity Intermittent Running Ability, and Injury Risk in Professional Rugby League Players
Authors: Hulin Billy T. , Gabbett Tim J. , Pickworth Nathan J. , Johnston Rich D. , Jenkins David G.
Published: September 2019

Purpose: To examine relationships among physical performance, workload, and injury risk in professional rugby league players. Methods: Maximal-effort (n = 112) and submaximal (n = 1084) running performances of 45 players were recorded from 1 club over 2 consecutive seasons. Poorer and better submaximal running performance was determined by higher and lower exercise heart rates, respectively. Exponentially weighted moving averages and daily rolling averages were used to assess microtechnology-derived acute and chronic field-based workloads. The associations among within-individual submaximal running performance, workload, and noncontact lower-limb injury were then investigated. Results: The injury risk associated with poorer submaximal performance was “likely” greater than stable (relative risk = 1.8; 90% confidence interval, 0.9–3.7) and better submaximal performance (relative risk = 2.0; 90% confidence interval, 0.9–4.4). Compared with greater submaximal performance, poorer performance was associated with lower chronic workloads (effect size [d] = 0.82 [0.13], large) and higher acute:chronic workload ratios (d = 0.49 [0.14], small). Chronic workload demonstrated a “nearly perfect” positive relationship with maximal-effort running performance (exponentially weighted moving average, R2 = .91 [.15]; rolling average, R2 = .91 [.14]). At acute:chronic workload ratios >1.9, no differences in injury risk were found between rolling average and exponentially weighted moving average methods (relative risk = 1.1; 90% confidence interval, 0.3–3.8; unclear). Conclusions: Reductions in submaximal running performance are related with low chronic workloads, high acute:chronic workload ratios, and increased injury risk. These findings demonstrate that a submaximal running assessment can be used to provide information on physical performance and injury risk in professional rugby league players.
Campylobacter jejuni Strains Associated with Wild Birds and Those Causing Human Disease in Six High-Use Recreational Waterways in New Zealand
Authors: Shrestha Rima D. , Midwinter Anne C. , Marshall Jonathan C. , Collins-Emerson Julie M. , Pleydell Eve J. , French Nigel P.
Published: September 2019

In 2016, there was a large-scale waterborne outbreak of campylobacteriosis in New Zealand, which was estimated to have affected over 5,000 people. This highlighted the need for a greater understanding of the sources of contamination of both surface and groundwater and risks associated with exposure to both drinking and recreational water. This study reports the prevalence and population structure of
Campylobacter jejuni
in six recreational waters of the Manawatu-Wanganui region of New Zealand and models the relationship between
Campylobacter
spp. and ruminant-associated
Campylobacter
and the parameters “sites,” “months,” and “river flow.” Here, we demonstrate that both low and high river flows, month of the year, and recreational sites could influence the
Campylobacter
isolation from recreational waters. The presence of genotypes associated with human infection allowed us to describe potential risks associated with recreational waters.
Differentiation into an Effector Memory Phenotype Potentiates HIV-1 Latency Reversal in CD4+T Cells
Authors: Kulpa Deanna A. , Talla Aarthi , Brehm Jessica H. , Ribeiro Susan Pereira , Yuan Sally , Bebin-Blackwell Anne-Gaelle , Miller Michael , Barnard Richard , Deeks Steven G. , Hazuda Daria , Chomont Nicolas , Sékaly Rafick-Pierre
Published: September 2019

By performing phenotypic analysis of latency reversal in CD4+T cells from virally suppressed individuals, we identify the TEMsubset as the largest contributor to the inducible HIV reservoir. Differential responses of memory CD4+T cell subsets to latency-reversing agents (LRAs) demonstrate that HIV gene expression is associated with heightened expression of transcriptional pathways associated with differentiation, acquisition of effector function, and cell cycle entry.In vitromodeling of the latent HIV reservoir in memory CD4+T cell subsets identify LRAs that reverse latency with ranges of efficiency and specificity. We found that therapeutic induction of latency reversal is associated with upregulation of identical sets of TEM-associated genes and cell surface markers shown to be associated with latency reversal in ourex vivoandin vitromodels. Together, these data support the idea that the effector memory phenotype supports HIV latency reversal in CD4+T cells.
Ecological and Genomic Attributes of Novel Bacterial Taxa That Thrive in Subsurface Soil Horizons
Authors: Brewer Tess E. , Aronson Emma L. , Arogyaswamy Keshav , Billings Sharon A. , Botthoff Jon K. , Campbell Ashley N. , Dove Nicholas C. , Fairbanks Dawson , Gallery Rachel E. , Hart Stephen C. , Kaye Jason , King Gary , Logan Geoffrey , Lohse Kathleen A. , Maltz Mia R. , Mayorga Emilio , O’Neill Caitlin , Owens Sarah M. , Packman Aaron , Pett-Ridge Jennifer , Plante Alain F. , Richter Daniel D. , Silver Whendee L. , Yang Wendy H. , Fierer Noah
Published: September 2019

Soil profiles are rarely homogeneous. Resource availability and microbial abundances typically decrease with soil depth, but microbes found in deeper horizons are still important components of terrestrial ecosystems. By studying 20 soil profiles across the United States, we documented consistent changes in soil bacterial and archaeal communities with depth. Deeper soils harbored communities distinct from those of the more commonly studied surface horizons. Most notably, we found that the candidate phylumDormibacteraeota(formerly AD3) was often dominant in subsurface soils, and we used genomes from uncultivated members of this group to identify why these taxa are able to thrive in such resource-limited environments. Simply digging deeper into soil can reveal a surprising number of novel microbes with unique adaptations to oligotrophic subsurface conditions.
Deleterious Effects of Neonicotinoid Pesticides on Drosophila melanogaster Immune Pathways
Authors: Chmiel John A. , Daisley Brendan A. , Burton Jeremy P. , Reid Gregor
Published: September 2019

Sublethal exposure to certain pesticides (e.g., neonicotinoid insecticides) is suspected to contribute to honey bee (
Apis mellifera
) population decline in North America. Neonicotinoids are known to interfere with immune pathways in the gut of insects, but the underlying mechanisms remain elusive. We used a
Drosophila melanogaster
model to understand how imidacloprid (a common neonicotinoid) interferes with two innate immune pathways—Duox and Imd. We found that imidacloprid dysregulates these pathways to reduce hydrogen peroxide production, ultimately leading to a dysbiotic shift in the gut microbiota. Intriguingly, we found that presupplementation with probiotic bacteria could mitigate the harmful effects of imidacloprid. Thus, these observations uncover a novel mechanism of pesticide-induced immunosuppression that exploits the interconnectedness of two important insect immune pathways.
Hydrodynamic Shape Changes Underpin Nuclear Rerouting in Branched Hyphae of an Oomycete Pathogen
Authors: Evangelisti Edouard , Shenhav Liron , Yunusov Temur , Le Naour–Vernet Marie , Rink Philipp , Schornack Sebastian
Published: September 2019

Despite their fungal morphology, oomycetes constitute a distinct group of protists related to brown algae and diatoms. Many oomycetes are pathogens and cause diseases of plants, insects, mammals, and humans. Extensive efforts have been made to understand the molecular basis of oomycete infection, but durable protection against these pathogens is yet to be achieved. We use a plant-pathogenic oomycete to decipher a key physiological aspect of oomycete growth and infection. We show that oomycete nuclei travel actively and over long distances within hyphae and during infection. Such movements require microtubules anchored on the centrosome. Nuclei hydrodynamically adapt their shape to travel in or against the flow. In contrast, fungi lack a centrosome and have much less flexible nuclei. Our findings provide a basis for modeling of flexible nuclear shapes in branched hyphal networks and may help in finding hard-to-evade targets to develop specific antioomycete strategies and achieve durable crop disease protection.
Influenza Virus Polymerase Mutation Stabilizes a Foreign Gene Inserted into the Virus Genome by Enhancing the Transcription/Replication Efficiency of the Modified Segment
Authors: Furusawa Yuri , Yamada Shinya , da Silva Lopes Tiago Jose , Dutta Jayeeta , Khan Zenab , Kriti Divya , van Bakel Harm , Kawaoka Yoshihiro
Published: September 2019

The reverse genetics method of influenza virus generation has enabled us to generate recombinant viruses bearing modified viral proteins. Recombinant influenza viruses expressing foreign genes have become useful tools in basic research, and such viruses can be utilized as efficient virus vectors or multivalent vaccines. However, the insertion of a foreign gene into the influenza virus genome often impairs virus replication, and the inserted genes are unstable. Elucidation of the mechanisms of foreign gene stabilization will help us to establish useful recombinant influenza viruses.
Increased Epithelial Oxygenation Links Colitis to an Expansion of Tumorigenic Bacteria
Authors: Cevallos Stephanie A. , Lee Jee-Yon , Tiffany Connor R. , Byndloss Austin J. , Johnston Luana , Byndloss Mariana X. , Bäumler Andreas J.
Published: September 2019

One of the environmental factors important for colorectal cancer formation is the gut microbiota, but the habitat filters that control its cancer-inducing activity remain unknown. Here, we show that chemically induced colitis elevates epithelial oxygenation in the colon, thereby driving an expansion of colibactin-producing
Escherichia coli
, a prooncogenic driver species. These data suggest that elevated epithelial oxygenation is a potential risk factor for colorectal cancer formation because the consequent changes in the gut habitat escalate the cancer-inducing activity of the microbiota.
Unraveling Melanin Biosynthesis and Signaling Networks in Cryptococcus neoformans
Authors: Lee Dongpil , Jang Eun-Ha , Lee Minjae , Kim Sun-Woo , Lee Yeonseon , Lee Kyung-Tae , Bahn Yong-Sun
Published: September 2019

Melanins are dark green, brown, or black pigments that serve as antioxidant, reactive oxygen species (ROS) scavengers that protect fungal pathogens from radiation and host immune responses.
Cryptococcus neoformans
, the major etiological agent of fungal meningoencephalitis, also utilizes melanin as a key virulence factor. In this basidiomycete pathogen, melanin production is regulated by the cAMP and high-osmolarity glycerol response (HOG) pathways, and yet its complex signaling networks remain poorly described. In this study, we uncovered novel melanin synthesis regulatory networks consisting of core transcription factors (TFs), including Bzp4, Usv101, Hob1, and Mbs1, and core kinases Gsk3 and Kic1. These networks were identified through coupling systematic analyses of the expression and epistatic relationships of TF and kinase mutant libraries in the presence of diverse melanin substrates with transcriptome profiling of the core TF mutants. Thus, this report provides comprehensive insight into the melanin-regulating pathways in
C. neoformans
and other fungal pathogens.
Lying in Wait: Modeling the Control of Bacterial Infections via Antibiotic-Induced Proviruses
Authors: Clifton Sara M. , Kim Ted , Chandrashekhar Jayadevi H. , O’Toole George A. , Rapti Zoi , Whitaker Rachel J.
Published: September 2019

Antibiotic resistance is a growing concern for management of common bacterial infections. Here, we show that antibiotics can be effective at subinhibitory levels when bacteria carry latent phage. Our findings suggest that specific treatment strategies based on the identification of latent viruses in individual bacterial strains may be an effective personalized medicine approach to antibiotic stewardship.
Metastatic basaloid squamous cell carcinoma of thymic origin
Authors: Phen Samuel , Wang Mindy X , Kelling Matthew , Bhattal Gurjaspreet K
Published: September 2019

A 57-year-old man with a known anterior mediastinal mass presented with abdominal distension, jaundice, and signs of urinary and bowel obstruction. Labs revealed leukocytosis, transaminitis, direct hyperbilirubinaemia and elevated levels of alkaline phosphatase, lactate dehydrogenase and uric acid. Subsequent imaging revealed the anterior mediastinal mass and diffuse liver lesions consistent with metastatic disease. MRI of the spine and brain were negative for metastases. Liver biopsy and immunohistochemistry revealed basaloid squamous cell carcinoma of thymic origin. Treatment with capecitabine was initiated but was complicated by worsening liver and kidney failure. Eventually, due to continued worsening of the patient’s condition and minimal treatment response, capecitabine was stopped during cycle 1 and the patient was discharged to inpatient hospice with comfort care. In this case report, we highlight the presenting features, imaging findings and management of a patient with metastatic thymic carcinoma.
Primary cytomegalovirus infection with invasive disease in a patient with inflammatory bowel disease
Authors: Gong Jingyi , Meyerowitz Eric Allan , Isidro Raymond A , Kaye Kenneth M
Published: September 2019

A 37-year-old woman with a history of inflammatory bowel disease on mercaptopurine presented with a week of recurrent fever, headache, myalgias and mildly elevated serum transaminases and leucopenia. Her workup revealed primary cytomegalovirus (CMV) infection with atypical lymphocytosis, elevated viral load, positive IgM and negative IgG. Two weeks after her initial presentation, she developed odynophagia and diarrhoea prompting endoscopic evaluation with biopsies, which demonstrated CMV disease of the gastrointestinal tract. Her fever and systemic symptoms improved rapidly with initiation of intravenous ganciclovir. She was transitioned to and maintained on oral valganciclovir until two and half months after discharge when her symptoms and lab abnormalities had fully subsided.
A case of catecholamine-induced cardiomyopathy treated with extracorporeal membrane oxygenation
Authors: Garla Vishnu Vardhan , Gosi Shiva , Kanduri Swetha , Lien Lillian
Published: September 2019

A 55-year-old female patient was presented with severe dyspnea due to sudden onset of heart failure (ejection fraction (EF) <10%). Echocardiogram showed a takotsubo pattern with an akinetic apical segment. Coronary angiography did not reveal any obstructive disease. She became hypotensive which was refractory to conventional pressor agents. Catecholamine-induced cardiomyopathy was suspected after the CT scan of the abdomen showed a 4 cm necrotic right adrenal mass consistent with pheochromocytoma (PHEO). Venous arterial extracorporeal membrane oxygenation and α blockers were initiated. There was a rapid improvement in cardiac function with EF normalising in 1 week. Subsequently, β-blockers were added and right adrenalectomy was done 3 weeks after the admission. She did extremely well after surgery with her blood pressure normalising without the need for antihypertensive therapy. Genetic evaluation revealed no pathogenic mutations implicated in the development of PHEO.
Use of three-dimensional printing and intraoperative navigation in the surgical resection of metastatic acetabular osteosarcoma
Authors: Heunis Julia C , Cheah Jonathan W , Sabnis Amit J , Wustrack Rosanna L
Published: September 2019

A 21-year-old man underwent a joint-preserving posterior acetabular resection of metastatic osteosarcoma using a three-dimensional (3D) printed model and intraoperative navigation. The combined application of these advanced technologies can allow for surgical planning of osteotomies involving complex anatomy and help guide resections intraoperatively. They can maximise the achievement of negative oncological margins, preservation of native hip stability and critical neurovascular structures, and optimal postoperative function in an effort to resect all clinically evident disease. For this particular patient, with secondary bony metastases, they allowed for a safe and well-tolerated procedure that ultimately afforded him palliative benefit, improved quality of life and, conceivably, prolonged survival in the setting of a devastating prognosis. Although he, sadly, has since passed away, he survived for over 2 years after initial metastasis with preserved hip stability and the ability to graduate college, stay active and maintain a quality of life that addressed his goals of care.
Pellagra in the USA: unusual manifestations of a rare entity
Authors: Rivadeneira Ana , Moyer Patricia , Salciccioli Justin D
Published: September 2019

The case involves a 62-year-old female native of the USA with a history of bipolar disorder and chronic obstructive pulmonary disease who presented with intractable diarrhoea. Prior to the index admission, she was admitted to the intensive care unit and required pericardiocentesis for an idiopathic pericardial effusion with tamponade physiology. Following discharge, she suffered intractable diarrhoea and represented for medical evaluation. She had a painful, swollen tongue as well as persistent hypoglycaemia and required glucose infusions. She had adrenal function testing which revealed adrenal insufficiency. Vitamin testing revealed normal B12and folate levels but undetectable levels of thiamine, riboflavin and niacin. Her symptoms and signs resolved entirely with appropriate vitamin supplementation. Niacin (vitamin B3) is essential for multiple metabolic pathways, and severe deficiency may cause clinical syndrome of pellagra which is most commonly associated with diarrhoea, delirium and dermatitis. Additional physiological derangements may include adrenal insufficiency, insulin hypersensitivity and pericarditis.