bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of amorphous magnetic materials under high-frequency non-sinusoidal excitations
Authors: Rahman Md. Ashib , Islam Md. Rabiul , Muttaqi Kashem M. , Sutanto Danny
Published: March 2019

In power electronic based energy conversion, the high-frequency transformer (HFT) is usually excited with a high-frequency (HF) square wave voltage generated from a power electronic converter circuit (PEC). A PEC needs a reasonable dead-band (DB) and the inclusion of the DB changes the shape of the square wave. In this paper, for the characterization of the core, the DB is varied to produce different non-sinusoidal excitation voltages and an optimized excitation voltage is identified. The effect of the DB on the hysteresis loop of the HFT is also demonstrated. The mathematical analysis shows that the inclusion of the DB causes the core loss to decrease for a fixed excitation voltage and frequency. However, an increased DB produces a higher distortion at the output voltage and the current of HFT. Therefore, an optimized DB is mandatory to minimize the core loss and the distortion at the same time. Additionally, the specific loss scenario of the core under the HF triangular and trapezoidal wave voltage excitation is investigated. To validate the findings, an optimized core is simulated in COMSOL Multiphysics software and a prototype core is developed in the laboratory using the amorphous magnetic material.
Development of a reliable probes
in situ
linear exchange module based on an environment control atomic force microscope
Authors: Zou Yijia , Jiang Liang , Lin Bin , Liu Jinwei , Zhou Zitong , Qian Linmao
Published: March 2019

In this work, a reliable atomic force microscope (AFM) probes in situ linear exchange module based on a scanned-sample environment control AFM was developed. The reliability and functionality of the module were experimentally verified through surface topography scanning tests and wear tests under different conditions. The module is able to install up to three AFM probes simultaneously, and in situ exchange different AFM probes inside the chamber so that different measurements in the designated environments can be carried out continuously as required. Without opening the chamber and breaking the atmosphere, contaminants from outside can be effectively avoided, and unpredictable physical/chemical change of the sample can be prevented. The module can be potentially used as a critical tool in studying nanotribology.
Bandgap widening by disorder in rainbow metamaterials
Authors: Celli Paolo , Yousefzadeh Behrooz , Daraio Chiara , Gonella Stefano
Published: March 2019

Stubbed plates, i.e., thin elastic sheets endowed with pillar-like resonators, display subwavelength, locally resonant bandgaps that are primarily controlled by the intrinsic resonance properties of the pillars. In this work, we experimentally study the bandgap response of a tunable heterogeneous plate endowed with reconfigurable families of pillars. We demonstrate that, under certain circumstances, both the spectrum of resonant frequencies of the pillars and their spatial arrangement influence the filtering characteristics of the system. Specifically, both spatially graded and disordered arrangements result in bandgap widening. Moreover, the spectral range over which attenuation is achieved with random arrangements is on average wider than the one observed with graded configurations.
Advection of droplet collision in centrifugal microfluidics
Authors: Liu Xun , Ji Yuan , Deng Yongbo , Wu Yihui
Published: March 2019

Centrifugal microfluidics has been developed into a powerful technology in chemistry and biology. Its carrier devices allow us to control flows without external pumps, integrate multiple functions onto a disk, and reduce the consumption of reagents or samples. In centrifugal microfluidics, an artificial gravitational field, which determines the volume forces imposed on the microfluid, can be created by the rotating operation of a disc-like microfluidic chip. Centrifugal microfluidics can be a preponderant approach for droplet manipulation because the dimensionless numbers (e.g., the Reynolds number and the Bond number) of the microflows can be controlled by the reasonable design of such a disc-like chip. To study the advection of droplets in a centrifugal microfluidic chip, this paper presents a numerical investigation for the droplet collisions under different Bond numbers and Reynolds numbers. The progress of the collision advection is simulated by solving laminar flow equations and phase-field equations. The distribution of the mixed droplets is described using particle tracking methods. By evaluating the extending ratio of the interface and the barycenter deviation, it is demonstrated that the Bond number and Reynolds number affect different aspects of the advection. For instance, higher Bond numbers produce larger barycenter deviation and higher Reynolds numbers generate a more chaotic distribution. These simulations reveal the advection of droplet collisions under different Bond numbers and Reynolds numbers. Revealing the effects of these dimensionless numbers and advection mechanism can promote more reasonable design and operation of the centrifugal microfluidic platforms.
Reversible transition of volatile to non-volatile resistive switching and compliance current-dependent multistate switching in IGZO/MnO RRAM devices
Authors: Abbas Haider , Ali Asif , Jung Jongwan , Hu Quanli , Park Mi Ra , Lee Hyun Ho , Yoon Tae-Sik , Kang Chi Jung
Published: March 2019

A controllable and reversible transition of volatile and non-volatile resistive switching is presented in Ag/indium-gallium-zinc oxide (IGZO)/manganese oxide (MnO)/Pt bilayer resistive memory devices. The coexistence of volatile and non-volatile switching characteristics was demonstrated by controlling the current compliance during the SET process. With lower current compliance (<50 μA), the formation of an unstable conducting filament presented typical diode-like non-volatile switching. A reversible transition from volatile to non-volatile switching could be obtained by applying a higher current compliance (≥50 μA). Moreover, highly uniform multistate memory characteristics were achieved by modulating the current compliance in the non-volatile switching region. The coexistence of volatile and multistate non-volatile resistive switching behaviors with a reversible transition demonstrates the capability of developing a selector element for crossbar arrays and the application for next generation multistate high-density storage with the same Ag/IGZO/MnO/Pt device.
Numerical study on the flow over two circular disks in tandem arrangement
Authors: Liu Minghou , Xie Chen , Yang Jianzhi , Zhu Xiaowei , Yao Mengyun
Published: March 2019

The flows over the two circular disks in tandem arrangement at low Reynolds numbers are numerically studied using large-eddy simulations. Both disks have the same aspect ratio (χ = d/w = 5, where d and w are, respectively, the diameter and the thickness of the disk), while the upstream disk has a coaxial hole in D diameter. First, the effect of the Reynolds number on the near-wake evolution of the tandem disks with spacing of l/d = 0.1 is investigated. Compared with a single circular disk, it is found that the upstream apertured disk (D/d = 0.2) delays the wake transition. Four bifurcations, i.e., “Steady state,” “Zig-zig,” “Zig-Zag,” and “Weakly chaotic” modes, are captured at critical Reynolds numbers of 178, 207, 212, and 275, respectively. Second, the effect of disk spacing on near-wake evolution is studied for Re = 200 and D/d = 0.2. The wake is steady and planar-symmetric at l/d = 1, in which a totally new wake mode characterized by a three-thread wake is observed. The wake becomes unsteady but planar-symmetric at l/d = 1.5. At l/d = 2, however, the planar-symmetric wake structures are all broken. The upstream disk wake retains planar-symmetry, while the downstream disk wake is similar to the “Reflectional-symmetry-broken” mode in a single disk wake. The planar symmetry is recovered for both disks at l/d = 6. It is found that for l/d > 3, the interaction between the two disks becomes weaker as the spacing increases. Finally, the effect of disk spacing on the drag and lift coefficients for each disk is examined. When disk spacing is constant, the lift coefficient of the upstream disk is always lower than that of the downstream disk. The drag coefficient of each disk in tandem is smaller than that of a single disk. With the increase in disk spacing, the drag coefficient of the upstream disk changes little while the drag coefficient of the downstream disk increases rapidly.
Numerical investigation of solitary wave slamming on an oscillating wave surge converter
Authors: Cheng Yong , Li Gen , Ji Chunyan , Zhai Gangjun
Published: March 2019

A solitary wave slamming on an Oscillating Wave Surge Converter (OWSC) is numerically investigated using a time-domain higher-order boundary element method with fully non-linear boundary conditions. A stretched coordinate is implemented to improve the numerical efficiency as long as the slamming peak pressure occurs. The potential of the thin long jet is assumed to vary linearly, while the process of jet detaching is simulated through the domain decomposition method so that the local highly oscillatory pressure can be avoided. Two auxiliary functions are applied simultaneously to decouple the mutual dependence between the flap motion and the fluid flow. A unique mesh scheme is employed to simulate the free surface with strong deformation, through which the smallest meshes are distributed near the largest pressure gradient on the body and the mesh size increases gradually at a ratio. The validity of the present model to simulate the solitary wave and the slamming event is verified, respectively, based on which relatively comprehensive parameter studies are then performed. Through analyzing the flap’s motion states, the free surface profiles, and the pressure distributions, it is found that several unique phenomena and mechanisms exist in the solitary waves slamming on an OWSC.
Scattering statistics in nonlinear wave chaotic systems
Authors: Zhou Min , Ott Edward , Antonsen Thomas M. , Anlage Steven M.
Published: March 2019

The Random Coupling Model (RCM) is a statistical approach for studying the scattering properties of linear wave chaotic systems in the semi-classical regime. Its success has been experimentally verified in various over-moded wave settings, including both microwave and acoustic systems. It is of great interest to extend its use in nonlinear systems. This paper studies the impact of a nonlinear port on the measured statistical electromagnetic properties of a ray-chaotic complex enclosure in the short wavelength limit. A Vector Network Analyzer is upgraded with a high power option, which enables calibrated scattering (S) parameter measurements up to +43dBm. By attaching a diode to the excitation antenna, amplitude-dependent S-parameters and Wigner reaction matrix (impedance) statistics are observed. We have systematically studied how the key components in the RCM are affected by this nonlinear port, including the radiation impedance, short ray orbit corrections, and statistical properties. By applying the newly developed radiation efficiency extension to the RCM, we find that the diode admittance increases with the excitation amplitude. This reduces the amount of power entering the cavity through the port so that the diode effectively acts as a protection element. As a result, we have developed a quantitative understanding of the statistical scattering properties of a semi-classical wave chaotic system with a nonlinear coupling channel.
Enhanced diffusion, swelling, and slow reconfiguration of a single chain in non-Gaussian active bath
Authors: Chaki Subhasish , Chakrabarti Rajarshi
Published: March 2019

A prime example of a non-equilibrium or active environment is a biological cell. In order to understand in vivo functioning of biomolecules such as proteins and chromatins, a description beyond equilibrium is absolutely necessary. In this context, biomolecules have been modeled as Rouse chains in a Gaussian active bath. However, these non-equilibrium fluctuations in biological cells are non-Gaussian. This motivates us to take a Rouse chain subjected to a series of pulses of force with a finite duration, mimicking the run and tumble motion of a class of microorganisms. Thus by construction, this active force is non-Gaussian. Our analytical calculations show that the mean square displacement (MSD) of the center of mass grows faster and even shows superdiffusive behavior at higher activity. The MSD of a tagged monomer in an active bath also shows superdiffusion at an intermediate time unlike a monomer of a Rouse chain. In the case of a short chain length, reconfiguration is slower and the reconfiguration time of a chain with N monomers scales as Nσ, with σ ≈ 1.6 − 2. In addition, the chain swells. We compare this activity-induced swelling with that of a Rouse chain in a Gaussian active bath. In principle, our predictions can be verified by future single molecule experiments.
Effect of the Prandtl number on the instabilities of the thermocapillary flow in an annular pool
Authors: Liu Hao , Zeng Zhong , Yin Linmao , Qiu Zhouhua , Zhang Liangqi
Published: March 2019

This paper is devoted to the instability mechanisms of the thermocapillary flow in an annular pool. The stability limit of the axisymmetric basic state was studied over a wide range of Prandtl numbers (0.001 ≤ Pr ≤ 6.7) using linear stability analysis based on the spectral element method. The results demonstrate five types of instabilities, and the corresponding instability mechanisms were revealed by disturbance energy analysis. In particular, in the narrow range 1.4 ≤ Pr ≤ 1.53, with the increase in the Marangoni number, three transitions between the axisymmetric steady flow and the three-dimensional oscillatory flow were found, owing to the coupling and interaction of the hydrodynamic and hydrothermal instability mechanisms.
Measurement of the electron energy distribution in moving striations at low gas pressures
Authors: Godyak V. A. , Alexandrovich B. M. , Kolobov V. I.
Published: March 2019

The time-resolved Electron Energy Distribution Functions (EEDFs) have been measured at different phases of moving striations in a positive column of DC discharge in argon gas. A very low gas pressure of 10 mTorr, a high energy resolution (to resolve the low energy part of the EEDF), and the dynamic range up to 3–4 orders of magnitude (to resolve the EEDF tail) with a temporal resolution of 2.5 μs distinguish our work from previous publications. The measured EEDFs reveal drastic changes in time of their low energy parts with the formation of a low energy peak. The observed EEDF dynamics is explained in the framework of nonlocal electron kinetics as electric field reversals and the trapping of low-energy electrons in potential wells propagating with striation along the discharge tube. The formation of the low energy peak in the EEDF is similar to that in rf capacitive and inductive discharges at low gas pressures where the low-energy electrons are trapped in the potential well created by the ambipolar electric field and cannot penetrate into the areas of electron heating by strong rf electric fields.
Patterns of alcohol consumption among people with major chronic diseases
Authors: Pham Thi Thu Le , Callinan Sarah , Livingston Michael
Published: March 2019

Risky alcohol use places those with existing chronic conditions at increased risk of medical complications. Yet, there is little research assessing the alcohol consumption among this group. The aim of this study is to assess the prevalence of risky drinking among people with a range of chronic diseases. As part of the 2013 National Drug Strategy Household Survey (NDSHS), 22684 Australians aged ≥18 years answered questions about their experience of chronic diseases and their drinking patterns. Nearly 18% (CI: 17.2–19.3) of people with chronic disease reported drinking at a long-term risky level, roughly the same rate as those without chronic disease (19.3%, (CI: 18.6–20.2)). Nearly one-quarter, 24% (CI: 23.0–25.3), of people with chronic diseases drank at levels of increased short-term risk, significantly less than the rest of the sample. Respondents with mental illness were more likely to drink at risky levels than the rest of the sample, while the reverse was true of those with diabetes. Overall, those with chronic diseases have similar drinking patterns to the rest of the population, despite increased risks associated with this consumption. Regular screening and subsequent brief interventions for those with chronic disease, particularly mental illness and cancer, are recommended.
Soil aggregation and soil fraction associated carbon under different vegetation types in a complex landscape
Authors: Li Xiaoqing , Vogeler Iris , Schwendenmann Luitgard
Published: March 2019

Land cover change has been shown to affect soil characteristics and soil organic carbon (SOC) storage. However, little is known about the driving factors associated with soil carbon (C) stabilisation in complex landscapes. This study was conducted to investigate the effects of both inherent soil characteristics and recent vegetation cover change on soil aggregation and soil fraction associated C in a complex landscape. The specific objectives were: (1) determine bulk soil properties and SOC saturation deficit; (2) quantify soil aggregation, soil size-density fractions, and soil fraction associated C; and (3) identify the factors that influence soil fractions and soil fraction associated C in two adjacent catchments differing in vegetation cover, Central Otago, New Zealand. Catchment GH1 (n = 17 plots) was dominated by tussock grassland and native shrubs. Catchment GH2 (n = 21 plots) was converted from tussock grassland into a pine forest in 1981. The catchments differed in soil texture (e.g. sand content GH1: 62.9%, GH2: 50.7%, P = 0.007), soil SOC stocks (GH1: 5.0 kg C m−2, GH2: 4.3 kg C m−2, P = 0.04), mean weight diameter (MWD) (GH1: 782.3 µm, GH2: 736.5 µm, P = 0.002), and proportion of the macroaggregate heavy fraction (macro_HF) (GH1: 72%, GH2: 55%, P = 0.01). No significant differences were found in SOC saturation deficit (GH1: 14.8 mg g−1, GH2: 13.1 mg g−1, P = 0.13). Dominant vegetation cover explained 21% of the variation in MWD in GH1, whereas silt+clay C content explained 31.6% of the MWD variation in GH2. The macro_HF fraction was negatively correlated with the proportion of silt+clay. Our findings illustrate that physical and chemical soil characteristics are important drivers in such a complex landscape and may have masked the effect of recent vegetation change on soil aggregation, and soil fraction associated C.
Preparation method of low-oxygen Ti-6Al-4V alloy by solid state re-deoxidation using calcium
Authors: Kim Taeheon , Kim Kwangmin , Oh Jung-Min , Park Jeshin , Lim Jae-Won
Published: March 2019

The oxygen concentration in commercial Ti-6Al-4 V alloys was reduced to less than 400 ppm in this study by the method of solid state re-deoxidation, using calcium as a reductant. The concentration of oxygen in the deoxidised Ti-6Al-4 V alloy was 630 ppm at the optimum deoxidation temperature of 1000°C. When the degree of vacuum was increased and re-deoxidation was carried out, the oxygen concentration decreased to 355 ppm. Therefore, it is possible to prepare a Ti-6Al-4 V alloy with an oxygen concentration of less than 400 ppm by using the solid state re-deoxidation method at a high degree of vacuum of 1.5 × 10-6 Torr.
Improvement of pulmonary arterial hypertension, inflammatory response, and epithelium injury by dual activation of cAMP/cGMP pathway in a rat model of monocrotaline-induced pulmonary hypertension
Authors: Muraki Yo , Naito Takako , Tohyama Kimio , Shibata Sachio , Kuniyeda Kanako , Nio Yasunori , Hazama Masatoshi , Matsuo Takanori
Published: March 2019

Pulmonary hypertension (PH) is a life-threatening lung disease. PH with concomitant lung diseases, e.g., idiopathic pulmonary fibrosis, is associated with poor prognosis. Development of novel therapeutic vasodilators for treatment of these patients is a key imperative. We evaluated the efficacy of dual activation of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) using an active, small-molecule phosphodiesterase (PDE4)/PDE5 dual inhibitor (Compound A). Compound A increased both cAMP and cGMP levels in WI-38 lung fibroblasts and suppressed the expressions of type-1 collagen α1 chain and fibronectin. Additionally, compound A reduced right ventricular weight/left ventricular weight+septal weight ratio, brain natriuretic peptide expression levels in right ventricle, C─C motif chemokine ligand 2 expression levels in lung, and plasma surfactant protein D. Our data indicate that dual activation of cAMP/cGMP pathways may be a novel treatment strategy for PH.
Radiographic and clinical outcomes following etanercept monotherapy in Japanese methotrexate-naïve patients with active rheumatoid arthritis
Authors: Takeuchi Tsutomu , Miyasaka Nobuyuki , Pedersen Ron , Sugiyama Noriko , Hirose Tomohiro
Published: March 2019

Objectives: Compare outcomes with methotrexate (MTX) or etanercept (ETN) monotherapy in Japanese patients with active rheumatoid arthritis (RA) who were MTX-naïve or with intolerance or inadequate response to prior MTX (MTX-IR).

Methods: Post hoc analysis of a phase 3 study comparing MTX, ETN 10 mg twice weekly, and ETN 25 mg twice weekly in Japanese patients with RA. Disease activity was evaluated using American College of Rheumatology (ACR) scores and 28-joint Disease Activity Score (DAS28), radiographic progression evaluated using van der Heijde’s modified Total Sharp Score (mTSS), and functional status evaluated using Health Assessment Questionnaire Disability Index (HAQ-DI).

Results: Among MTX-naïve and MTX-IR patients, greater proportions of those randomized to either ETN group achieved ACR20, ACR50, ACR70, DAS28 ≤3.2 or <2.6, clinically relevant inhibition of mTSS changes, and reductions in HAQ-DI compared with MTX at the majority of time points. There were very few clinically meaningful differences between ETN groups for any of the variables evaluated.

Conclusion: ETN monotherapy was more effective than MTX in both MTX-naïve and MTX-IR patients, with very few clinically meaningful differences between ETN 10 mg and ETN 25 mg when given twice weekly. The relative benefits of ETN were greater in MTX-naïve patients than MTX-IR patients.

ClinicalTrials.gov identifier

NCT00445770
STIMULATION BY THE SALTS OF THE NORMAL ALIPHATIC ACIDS IN THE ROCK BARNACLE BALANUS BALANOIDES
Authors: Cole William H.
Published: March 2019

In Vol. 15, No. 6, July 20, 1932, page 620, in the first line under References, for J. Gen. Physiol., 1931–32, 15, 62, read J. Gen. Physiol., 1931–32, 15, 621.
Nitroxyl (HNO) targets phospholamban cysteines 41 and 46 to enhance cardiac function
Authors: Keceli Gizem , Majumdar Ananya , Thorpe Chevon N. , Jun Seungho , Tocchetti Carlo G. , Lee Dong I. , Mahaney James E. , Paolocci Nazareno , Toscano John P.
Published: March 2019

Nitroxyl (HNO) positively modulates myocardial function by accelerating Ca2+ reuptake into the sarcoplasmic reticulum (SR). HNO-induced enhancement of myocardial Ca2+ cycling and function is due to the modification of cysteines in the transmembrane domain of phospholamban (PLN), which results in activation of SR Ca2+-ATPase (SERCA2a) by functionally uncoupling PLN from SERCA2a. However, which cysteines are modified by HNO, and whether HNO induces reversible disulfides or single cysteine sulfinamides (RS(O)NH2) that are less easily reversed by reductants, remain to be determined. Using an 15N-edited NMR method for sulfinamide detection, we first demonstrate that Cys46 and Cys41 are the main targets of HNO reactivity with PLN. Supporting this conclusion, mutation of PLN cysteines 46 and 41 to alanine reduces the HNO-induced enhancement of SERCA2a activity. Treatment of WT-PLN with HNO leads to sulfinamide formation when the HNO donor is in excess, whereas disulfide formation is expected to dominate when the HNO/thiol stoichiometry approaches a 1:1 ratio that is more similar to that anticipated in vivo under normal, physiological conditions. Thus, 15N-edited NMR spectroscopy detects redox changes on thiols that are unique to HNO, greatly advancing the ability to detect HNO footprints in biological systems, while further differentiating HNO-induced post-translational modifications from those imparted by other reactive nitrogen or oxygen species. The present study confirms the potential of HNO as a signaling molecule in the cardiovascular system.
A review of global-local-global linkages in economic land-use/cover change models
Authors: Hertel Thomas W , West Thales A P , Börner Jan , Villoria Nelson B
Published: March 2019

Global change drivers of land-use/cover change (LUCC) like population dynamics, economic development, and climate change are increasingly important to local sustainability studies, and can only be properly analyzed at fine-scales that capture local biophysical and socio-economic conditions. When sufficiently widespread, local feedback to stresses originating from global drivers can have regional, national, and even global impacts. A multiscale, global-to-local-to-global (GLG) framework is thus needed for comprehensive analyses of LUCC and leakage. The number of GLG-LUCC studies has grown substantially over the past years, but no reviews of this literature and their contributions have been completed so far. In fact, the largest body of literature pertains to global-to-local impacts exclusively, whereas research on local feedback to regional, national, and global spheres remain scarce, and are almost solely undertaken within large modeling institutes. As such, those are rarely readily accessible for modification and extension by outside contributors. This review of the recent GLG-LUCC studies calls for more open-source modeling and availability of data, arguing that the latter is the real constraint to more widespread analyses of GLG-LUCC impacts. Progress in this field will require contributions from hundreds of researchers around the world and from a wide variety of disciplines.
An overview of ABoVE airborne campaign data acquisitions and science opportunities
Authors: Miller C E , Griffith P C , Goetz S J , Hoy E E , Pinto N , McCubbin I B , Thorpe A K , Hofton M , Hodkinson D , Hansen C , Woods J , Larson E , Kasischke E S , Margolis H A
Published: March 2019

The 2017 Arctic Boreal Vulnerability Experiment Airborne Campaign (AAC) was one of the largest, most complex airborne science experiments conducted by NASA’s Earth Science Division. Between April and November, the AAC involved ten aircraft in more than 200 science flights that surveyed over 4 million km2 in Alaska and northwestern Canada. Many flights were coordinated with same-day ground-based measurements to link process-level studies with geospatial data products derived from satellite sensors. The AAC collected data spanning the critical intermediate space and time scales that are essential for a comprehensive understanding of scaling across the ABoVE Study Domain and ultimately extrapolation to the pan-Arctic using satellite data and ecosystem models. The AAC provided unique opportunities to validate satellite and airborne remote sensing data and data products for northern high latitude ecosystems. The science strategy coupled domain-wide sampling with L-band and P-band synthetic aperture radar (SAR), imaging spectroscopy, full waveform LIDAR, atmospheric trace gases (including carbon dioxide and methane), as well as focused studies using Ka-band SAR and solar induced chlorophyll fluorescence. Targets of interest included field sites operated by the ABoVE Science Team as well as the intensive and/or long-term sites operated by US and Canadian partners.
Characterization of hypersurfaces via the second eigenvalue of the Jacobi operator
Authors: Mendes Abraão
Published: March 2019

In this work we characterize certain immersed closed hypersurfaces of some ambient manifolds via the second eigenvalue of the Jacobi operator. First, we characterize the Clifford torus as the surface which maximizes the second eigenvalue of the Jacobi operator among all closed immersed orientable surfaces of

S

3

\mathbb {S}^3

with genus bigger than zero. After, we characterize the slices of the warped product

I

×
h

S

n

I\times _h\mathbb {S}^n

, under a suitable hypothesis on the warping function

h
:
I
⊂

R

→

R

h:I\subset \mathbb {R}\to \mathbb {R}

, as the only hypersurfaces which saturate a certain integral inequality involving the second eigenvalue of the Jacobi operator. As a consequence, we obtain that if

Σ
\Sigma

is a closed immersed hypersurface of

R

×

S

n

\mathbb {R}\times \mathbb {S}^n

, then the second eigenvalue of the Jacobi operator of

Σ
\Sigma

satisfies

λ
2

≤
n

\lambda _2\le n

and the slices are the only hypersurfaces which satisfy

λ
2

=
n

\lambda _2=n

.
Race in the Crucible of Literary Debate
Authors: Jerng Mark C
Published: March 2019

Both Caroline Levine’s Forms (2015) and Rita Felski’s The Limits of Critique (2015) use Bruno Latour’s Actor-Network-Theory to help them theorize reading practices for analyzing the interrelationships between literature and sociopolitical experience. In doing so, both disavow powerful understandings of the “social” produced across race and gender critique in African American and ethnic literary studies. This essay traces a connection backwards from Latour to the sociologist Gabriel Tarde to critiques of sociology by W. E. B. Du Bois. Du Bois’s understanding of the social and literary dimensions of “environing” critique assumptions embedded in the idea of networks, highlighting crucial experiences of being made not to act as constitutive of the social. The argument turns to brief syntheses of work by Saidiya Hartman, Hortense Spillers, Lisa Lowe, and Sau-Ling Cynthia Wong for models of thinking literary and social experience, suggesting that they need to be brought into these discussions of the normative values and methods of literary study. The essay concludes by reconsidering Winfried Fluck’s examination of these normative values in relation to dominant philosophies of history and questioning his assumptions about conditions of unfreedom.
Automated exploration of gene ontology term and pathway networks with ClueGO-REST
Authors: Mlecnik Bernhard , Galon Jérôme , Bindea Gabriela
Published: March 2019

Large scale technologies produce massive amounts of experimental data that need to be investigated. To improve their biological interpretation we have developed ClueGO, a Cytoscape App that selects representative Gene Onology terms and pathways for one or multiple lists of genes/proteins and visualizes them into functionally organized networks. Because of its reliability, userfriendliness and support of many species ClueGO gained a large community of users. To further allow scientists programmatic access to ClueGO with R, Python, JavaScript etc., we implemented the cyREST API into ClueGO. In this article we describe this novel, complementary way of accessing ClueGO via REST, and provide R and Phyton examples to demonstrate how ClueGO workflows can be integrated into bioinformatic analysis pipelines.

Availability and implementation

ClueGO is available in the Cytoscape App Store (http://apps.cytoscape.org/apps/cluego).

Supplementary information

Supplementary data are available at Bioinformatics online.
In Vivo Assay of Cortical Microcircuitry in Frontotemporal Dementia: A Platform for Experimental Medicine Studies
Authors: Shaw Alexander D , Hughes Laura E , Moran Rosalyn , Coyle-Gilchrist Ian , Rittman Tim , Rowe James B
Published: March 2019

The analysis of neural circuits can provide crucial insights into the mechanisms of neurodegeneration and dementias, and offer potential quantitative biological tools to assess novel therapeutics. Here we use behavioral variant frontotemporal dementia (bvFTD) as a model disease. We demonstrate that inversion of canonical microcircuit models to noninvasive human magnetoencephalography, using dynamic causal modeling, can identify the regional- and laminar-specificity of bvFTD pathophysiology, and their parameters can accurately differentiate patients from matched healthy controls. Using such models, we show that changes in local coupling in frontotemporal dementia underlie the failure to adequately establish sensory predictions, leading to altered prediction error responses in a cortical information-processing hierarchy. Using machine learning, this model-based approach provided greater case–control classification accuracy than conventional evoked cortical responses. We suggest that this approach provides an in vivo platform for testing mechanistic hypotheses about disease progression and pharmacotherapeutics.
Diversity of Feature Selectivity in Macaque Visual Cortex Arising from a Limited Number of Broadly Tuned Input Channels
Authors: Mohan Yamni S , Jayakumar Jaikishan , Lloyd Errol K J , Levichkina Ekaterina , Vidyasagar Trichur R
Published: March 2019

Spike (action potential) responses of most primary visual cortical cells in the macaque are sharply tuned for the orientation of a line or an edge, and neurons preferring similar orientations are clustered together in cortical columns. The preferred stimulus orientation of these columns span the full range of orientations, as observed in recordings of spikes and in classical optical imaging of intrinsic signals. However, when we imaged the putative thalamic input to striate cortical cells that can be seen in imaging of intrinsic signals when they are analyzed on a larger spatial scale, we found that the orientation domain map of the primary visual cortex did not show the same diversity of orientations. This map was dominated by just the one orientation that is most commonly preferred by neurons in the retina and the lateral geniculate nucleus. This supports cortical feature selectivity and columnar architecture being built upon feed-forward signals transmitted from the thalamus in a very limited number of broadly tuned input channels.
Estimated Impact of World Health Organization Latent Tuberculosis Screening Guidelines in a Region With a Low Tuberculosis Incidence: Retrospective Cohort Study
Authors: Ronald Lisa A , Campbell Jonathon R , Rose Caren , Balshaw Robert , Romanowski Kamila , Roth David Z , Marra Fawziah , Schwartzman Kevin , Cook Victoria J , Johnston James C
Published: March 2019

Background

Latent tuberculosis infection (LTBI) screening and treatment is a key component of the World Health Organization (WHO) EndTB Strategy, but the impact of LTBI screening and treatment at a population level is unclear. We aimed to estimate the impact of LTBI screening and treatment in a population of migrants to British Columbia (BC), Canada.

Methods

This retrospective cohort included all individuals (N = 1 080 908) who immigrated to Canada as permanent residents between 1985 and 2012 and were residents in BC at any time up to 2013. Multiple administrative databases were linked to identify people with risk factors who met the WHO strong recommendations for screening: people with tuberculosis (TB) contact, with human immunodeficiency virus, on dialysis, with tumor necrosis factor-alpha inhibitors, who had an organ/haematological transplant, or with silicosis. Additional TB risk factors included immunosuppressive medications, cancer, diabetes, and migration from a country with a high TB burden. We defined active TB as preventable if diagnosed ≥6 months after a risk factor diagnosis. We estimated the number of preventable TB cases, given optimal LTBI screening and treatment, based on these risk factors.

Results

There were 16 085 people (1.5%) identified with WHO strong risk factors. Of the 2814 people with active TB, 118 (4.2%) were considered preventable through screening with WHO risk factors. Less than half (49.4%) were considered preventable with expanded screening to include people migrating from countries with high TB burdens, people who had been prescribed immunosuppressive medications, or people with diabetes or cancer.

Conclusions

The application of WHO LTBI strong recommendations for screening would have minimally impacted the TB incidence in this population. Further high-risk groups must be identified to develop an effective LTBI screening and treatment strategy for low-incidence regions.
Sex Differences in Achievement and Faculty Rank in Academic Infectious Diseases
Authors: Manne-Goehler Jennifer , Kapoor Neena , Blumenthal Daniel M , Stead Wendy
Published: March 2019

Background

This study assesses differences in faculty rank between female and male infectious diseases (ID) faculty with academic appointments at US medical schools.

Methods

We analyzed a complete database of US physicians with medical school faculty appointments in 2014. This database consists of a linkage between the American Association of Medical Colleges faculty roster and a physician database from Doximity, and includes physician age, sex, years since residency completion, publications, National Institutes of Health grants, and registered clinical trials for all academic physicians by specialty. We used multivariable logistic regression models with medical school–specific fixed effects to assess sex differences in full professorship by specialty and the relationship between these factors and achieving the rank of full professor within ID. We compared this adjusted difference in ID to that of peer subspecialties.

Results

Among a total of 2016 academic ID physicians, there were 742 (37%) women who together accounted for 48.1% of assistant professors, 39.7% of associate professors, and 19.2% of full professors. Women faculty had fewer total (16.3 vs 28.3, P < .001) and first/last author publications (9.8 vs 20.4, P < .001). In adjusted models, the rate of full professorship (vs assistant or associate) among female compared to male ID physicians was large and significant (absolute adjusted difference, –8.0% [95% confidence interval, –11.9% to –4.1%]). This difference was greater in ID than in cardiology.

Conclusions

Significant sex differences in achieving the rank of full professor exist in academic ID, after adjustment for multiple factors known to influence these outcomes. Greater efforts should be made to address equity in academic ID.
Cooperative Overtaking Assistance System Based on V2V Communications and RTDB
Authors: Elleuch Islam , Makni Achraf , Bouaziz Rafik
Published: March 2019

Overtaking maneuvers in roads cause a large number of accidents. To prevent collisions, numerous cooperative overtaking assistance systems, based on Vehicular Ad hoc Networks (VANET), have been proposed. However, these systems may meet problems in case of data congestion or data loss. To improve overtaking safety, this paper studies the use of Vehicle-To-Vehicle (V2V) communications and Real-Time DataBases (RTDB). More precisely, we suggest a new integrated system, called Cooperative Overtaking Assistance Persistent System (COAPS), to better avoid potential collisions during overtaking maneuvers. Each vehicle stores its information in a local RTDB, along with the adjacent vehicles’ information. While detecting an overtaking intention, the vehicle COAPS queries its database and selects the preceding vehicle(s) and the oncoming one(s) from the other direction to make decision about the overtaking. It controls the overtaking in case of positive decision or reduces the vehicle speed to avoid a collision ahead, in the other case. Simulations of different driving scenarios, under the Vehicles In Network Simulation (VEINS) framework, show that COAPS provides a high level of overtaking safety due to the V2V communications, the RTDB and the notion of Quality of Data used to reduce the number of data freshness transactions.
“We” Before “Me”: Differences in Usage of Collectivistic and Individualistic Language Influence Judgments of Electability and Performance
Authors: Turner Jennifer R , Stanley Jennifer Tehan
Published: March 2019

Objectives

Older adults are often judged to be warm, but not competent, which contradicts their representation in positions of authority. This study sought to extend evidence of age differences in more individualistic (e.g., “I”) and collectivistic (e.g., “we”) language and explore their impact on judgments of performance and electability.

Method

Speeches from young and older adults who campaigned for a fictitious position were analyzed using Linguistic and Inquiry Word Count Software. Words fitting specified categories (e.g., pronouns, affect) were compared to outcome judgments obtained from trained coders on the dimensions of performance and electability.

Results

Older adults used significantly more “we”-language. Young adults used more “I”-language, and more positive affect, achievement, and power language. Language choices and coder judgments were associated such that the more “I”-language that was used during the speech, the less electable the candidate was judged. This relationship was not found for “we”-language.

Discussion

This study found no evidence for collectivistic language enhancing ratings of electability or performance; however, an age-invariable, negative relationship was obtained between increased individualistic language and reduced coder judgments of electability. This suggests that speakers should minimize “I”-statements to promote electability, a characteristic that is reflected more in older adults’ speeches than young.
Real-world Pattern of Biologic Use in Patients With Inflammatory Bowel Disease: Treatment Persistence, Switching, and Importance of Concurrent Immunosuppressive Therapy
Authors: Chen Chao , Hartzema Abraham G , Xiao Hong , Wei Yu-Jung , Chaudhry Naueen , Ewelukwa Ofor , Glover Sarah C , Zimmermann Ellen M
Published: March 2019

Background and aims

Medication persistence, defined as the time from drug initiation to discontinuation of therapy, has been suggested as a proxy for real-world therapeutic benefit and safety. This study seeks to compare the persistence of biologic drugs among patients with inflammatory bowel disease (IBD).

Methods

Patients with newly diagnosed IBD were included in a retrospective study using Truven MarketScan database. Treatment persistence and switching was compared among biologic medications including infliximab, adalimumab, certolizumab, golimumab, and vedolizumab. Predictors for discontinuation and switching were evaluated using time-dependent proportional hazard regression.

Results

In total, 5612 patients with Crohn’s disease (CD) and 3533 patients with ulcerative colitis (UC) were included in this analysis. Less than half of the patients continued using their initial biologic treatment after 1 year (48.48% in CD cohort; 44.78% in UC cohort). In the first year, adalimumab had the highest persistence and lowest switching rates for both CD (median survival time: 1.04 years) and UC (median survival time: 0.84 years). In subsequent years, infliximab users were more likely to persist in the use of biologic. Combination therapy with immunomodulators significantly decreased the risk of discontinuation, especially when immunomodulator therapy was started more than 30 days before the biologic (hazard ratio [HR], 0.22; CI, 0.16, 0.32). The major predictors for noncompliance included infection and hospitalization.

Conclusion

Overall, the persistence profiles of biologics suggest a high rate of dissatisfaction or adverse disease outcomes resulting in discontinuation and switching to a different agent. Early initiation of immunomodulators will substantially increase the persistence of biologic treatment.
Initial Assessment of Post-traumatic Stress in a US Cohort of Inflammatory Bowel Disease Patients
Authors: Taft Tiffany H , Bedell Alyse , Craven Meredith R , Guadagnoli Livia , Quinton Sarah , Hanauer Stephen B
Published: March 2019

Background

Post-traumatic stress (PTS), or the psycho-physiological response to a traumatic or life-threatening event, is implicated in medical patient outcomes. Emerging evidence suggests a complex relationship between PTS, the brain–gut axis, the gut microbiome, and immune function. Inflammatory bowel disease (IBD) may be susceptible to PTS and its subsequent impacts. To date, no study has evaluated PTS in IBD in the United States.

Methods

Adult patients with IBD were recruited from an outpatient gastroenterology practice, via social media, and via a research recruitment website. Patients with irritable bowel syndrome (IBS) were recruited as a comparison group. Participants completed demographic and disease information, surgical and hospitalization history, and the PTSD Checklist–Civilian Version (PCL-C). Statistical analyses evaluated rates of PTS in IBD and IBS, including differences between groups for PTS severity. Regression analyses determined potential predictors of PTS.

Results

One hundred eighty-eight participants (131 IBD, 57 IBS) completed the study. Thirty-two percent of IBD and 26% of IBS patients met the criteria for significant PTS symptoms based on PCL-C cutoffs. Inflammatory bowel disease patients are more likely to attribute PTS to their disease than IBS patients. Crohn’s disease (CD) patients appear to be the most likely to experience PTS, including those being hospitalized or undergoing ileostomy surgery. Symptom severity is the greatest predictor of PTS for ulcerative colitis and IBS.

Conclusions

Although PTS is relevant in both IBS and IBD, IBD patients are seemingly more susceptible to PTS due their disease experiences, especially CD patients. The nature of PTS symptoms may contribute to IBD disease processes, most notably through sleep disturbance and ANS arousal. Clinicians should assess for PTS in IBD patients as standard of care, especially after a hospitalization or surgery.
Lens Generalisation of τ-Functions for the Elliptic Discrete Painlevé Equation
Authors: Kels Andrew P , Yamazaki Masahito
Published: March 2019

We propose a new bilinear Hirota equation for $\tau$-functions associated with the $E_8$ root lattice that provides a “lens” generalisation of the $\tau$-functions for the elliptic discrete Painlevé equation. Our equations are characterised by a positive integer $r$ in addition to the usual elliptic parameters and involve a mixture of continuous variables with additional discrete variables, the latter taking values on the $E_8$ root lattice. We construct explicit $W(E_7)$-invariant hypergeometric solutions of this bilinear Hirota equation, which are given in terms of elliptic hypergeometric sum/integrals.
Tedizolid in vitro activity against Gram-positive clinical isolates causing bone and joint infections in hospitals in the USA and Europe (2014–17)
Authors: Carvalhaes Cecilia G , Sader Hélio S , Flamm Robert K , Mendes Rodrigo E
Published: March 2019

Background

Despite the advances in current healthcare, bone and joint infections (BJIs) are a major clinical challenge that frequently involve prolonged systemic antibiotic use. Healthcare providers consider tedizolid an attractive candidate for therapy in adults and children with BJI.

Objectives

We tested tedizolid against a US and European collection of Gram-positive BJI isolates (n = 797) consecutively collected from 2014 to 2017.

Methods

Organisms were tested by broth microdilution susceptibility methods following current CLSI guidelines and interpreted by both CLSI and EUCAST breakpoint criteria.

Results

Staphylococcus aureus (59.3%; 58.6% in the USA and 60.4% in Europe) was the most common pathogen with a 29.6% MRSA rate and tedizolid MIC50/90 of 0.12/0.25 mg/L (100% susceptible). CoNS (15.0% of BJI in adults and <5% in children) had tedizolid MIC50/90 values of 0.12/0.12 mg/L (99.1% susceptible). Tedizolid exhibited MIC50/90 values of 0.12/0.25 mg/L for all streptococci and enterococci. Overall, high susceptibility rates (>95%) for vancomycin, daptomycin and linezolid were observed and, based on MIC90 values, tedizolid (MIC90 0.12–0.25 mg/L) was 4- to 8-fold more potent than linezolid (MIC90 0.5–2  mg/L) against this collection of Gram-positive pathogens causing BJI.

Conclusions

This study showed that tedizolid had potent in vitro activity against contemporary Gram-positive cocci causing BJI in adults and children in US and European hospitals.