bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical and manometric investigation in constipated Chagasic patients with and without megacolon
Authors: Leite Arminda Caetano de Almeida e , Moreira Marise Amaral Rebouças , Barbosa Maria Alves , Júnior Hélio Moreira , Leite Paula Chrystina Caetano Almeida , Moreira José Paulo Teixeira 
Published: April 2019

AbstractBackground Chagasic colopathy is the second most common digestive manifestation, and constipation is the main symptom. The absence of the Rectoanal Inhibitory Reflex plays an important role in constipation and anal manometry is crucial for appropriate evaluation.Purpose Evaluate anal manometry findings (mainly Rectoanal Inhibitory Reflex) in Chagasic patients with chronic constipation, with and without megacolon and correlate these findings with clinical and demographic data.Methods Cross-sectional study of patients with chronic constipation who underwent Chagasic serologic test, barium enema, and anal manometry. The absence of Rectoanal Inhibitory Reflex was evaluated using the mid-P Exact Test.Results 64 Patients were included: 23 Chagasic patients with megacolon/megarectum (G1), 21 Chagasic patients without megacolon/megarectum (G2) and 20 non-Chagasic patients without megacolon/megarectum (G3). Chagasic patients with megacolon had a higher incidence of fecaloma (39%) compared to the other two groups (9.5% and 10% for G2 and G3, respectively, p = 0.03). Rectal capacity on manometry was statically higher for G1 patients. Rectoanal Inhibitory Reflex was absent in 91.3% of patients in G1, 47.29% in G2 and present in all patients in G3. There was a significant difference in the absence of the Rectoanal Inhibitory Reflex when comparing the groups (G1 vs. G2: p = 0.002, G1 vs. G3: p < 0.001, G2 vs. G3: p < 0.001).Conclusion The absence of RAIR confirms the diagnosis of Chagasic colopathy and endorses surgical treatment whenever clinical treatment fails. The presence of the RAIR in patients with positive serology for Chagas disease without megacolon/megarectum might not be due chagasic colopathy and other causes should be considered.
Two-time scale controller design for a high speed planar parallel manipulator with structural flexibility
Authors: Kang Bongsoo , Yeung Benny , Mills James K. 
Published: April 2019

SummaryPlanar parallel manipulators, with potential applications in high speed, high acceleration tasks such as electronic component placement, would be subject to mechanical vibration due to high inertial forces acting on the linkages and other components. To achieve high throughput capability, such motion induced vibration would have to be damped quickly, to reduce settling time of the platform position and orientation. This paper develops a two-time scale dynamic model of a three-degree-of-freedom planar parallel manipulator with structurally flexible linkages. Based on the two-time scale model, a composite controller, consisting of a computed torque controller for the slow time-scale or rigid body subsystem dynamics, and a linear-quadratic state-feedback regulator for the fast time-scale flexible dynamic subsystem, is designed. Simulation results show that the composite control scheme permits the parallel manipulator platform to follow a given desired trajectory, while damping structural vibration arising due to excitation from inertial forces.
Increasing the generalizability of economic evaluations: Recommendations for the design, analysis, and reporting of studies
Authors: Drummond Michael , Manca Andrea , Sculpher Mark 
Published: April 2019

Objectives:Health technology assessment (HTA) is increasingly an international activity, and HTA agencies collaborate to avoid unnecessary duplication of effort. However, the sharing of the results from HTAs raises questions about their generalizability; namely, are the results of an HTA undertaken in one country relevant to another?Methods:This study presents recommendations for increasing the generalizability of economic evaluations. They represent an important component of HTAs and are commonly thought to have limited generalizability.Results:Recommendations are given for studies using patient-level data (i.e., evaluations conducted alongside clinical trials) and for studies using decision analytic modeling.Conclusions:If implemented, the recommendations would increase the value for investments in HTA.
Didactic images in a thirteenth-century French music theory treatise: theScientia artis musiceof Hélie Salomon
Authors: DYER JOSEPH 
Published: April 2019

AbstractTheScientia artis musice, a music theory treatise completed in the year 1274 by Hélie Salomon, a cleric from the village of St-Astier (Périgord/Dordogne), covers all the usual topics treated in such sources: letter names, hexachord syllables, the claves (letter + syllable(s)), the musical hand, mutation, staff notation, clef placement and chant genres. It includes an incomplete tonary with representative chant genres together with a commentary on the seculorum (differentiae) appropriate to various chant incipits. A lengthy instruction on the performance of parallel four-voice organum is also included. TheScientiais the only medieval theory treatise whose eight illustrations (called ‘figurae’) include human figures. These images relate directly to matters covered in the treatise and serve to make its main points more easily committed to memory. Of especial interest is the image of an enthroned bishop that serves as the focal point for a novel exposition of the tonal system of chant as (1) a set of logical relations modelled after the Tree of Porphyry and (2) a variant of the tree of consanguinity. Since the sole surviving copy of the treatise is the original, all these details must reflect the author's intention.
Solar Occultation FTIR Spectrometry at Mars for Trace Gas Detection: A Sensitivity Study
Authors: Toon Geoffrey C. , Liebe Carl Christian , Nemati Bijan , Harris Ian , Kleinböhl Armin , Allen Mark , Hipkin Vicky , Drummond Jim , Soucy Marc‐André , Yung Yuk L. , Zeng Zhao‐Cheng , Wunch Debra , Wennberg Paul O. 
Published: April 2019

AbstractA sensitivity study has been performed to estimate detection limits of various atmospheric trace gases achievable by a Mars‐orbiting solar occultation Fourier transform infrared (FTIR) spectrometer. This was accomplished by first computing realistic limb transmittance spectra based on a model (T, P, VMR, and dust profiles) of the Mars atmosphere and adding appropriate noise and systematic errors based on assumed instrument design/configuration/performance. We then performed spectral fits to the resulting synthetic spectra to derive slant column abundances and their uncertainties. A profile retrieval was performed to infer limits of detection. This methodology was applied to a Mars‐orbiting FTIR solar occultation spectrometer covering the 850–4,300 cm−1 spectral region at 0.025‐cm−1 resolution. We conclude that most gases can be retrieved with a single‐occultation sensitivity of 20–100 ppt. But this sensitivity varies considerably with the dust loading, especially for gases whose strongest absorption bands are toward higher wavenumbers where scattering is large. We conclude that for CH4, the ν4 band centered at 1,305 cm−1, despite being more than 2 times weaker than the ν3 band centered at 3,015 cm−1, offers better sensitivity due to its close spectral proximity to the dust extinction minimum. We also conclude that for the purpose of CH4 detection, a high‐resolution (0.025 cm−1) broadband instrument would have a substantial advantage over a medium‐resolution (0.15 cm−1) instrument, despite the latter having a much larger signal‐to‐noise ratio.
The Sensitivity of Sprite Streamer Inception on the Initial Electron‐Ion Patch
Authors: Köhn C. , Chanrion O. , Neubert T. 
Published: April 2019

AbstractSprite streamers are bright atmospheric phenomena above thunderstorms powered by sufficiently high electric fields and free charges from inhomogeneities in the mesosphere or ionosphere. A common feature of recent simulations is that they model the streamer inception from spherical Gaussian electron‐ion patches. We here tackle the following question: How do the streamer inception time and streamer properties depend on the initial geometry? Therefore, we consider prolate (“cigar”) and oblate (“pancake”) electron‐ion patches aiming to understand the geometric influence on streamer inception speed, electric field evolution, branching time, and ohmic heating of streamers. We initiate patches of different geometry with fixed peak densities of 5·1011 m−3 or with a fixed total electron number of 9.40·1012 in ambient fields of 0.5 and 1.5 times the breakdown field and study the streamer evolution between 60 and 80 km altitude with a 2.5D cylindrical Monte Carlo particle code. We present the evolution of the electron density and of the electric field. In our simulations, the time for the electric field tips to develop into the regime where they can self sustain the discharge is shortest for streamers from prolate patches and longest for oblate patches. The branching time of negative fronts depends on the eccentricity and increases for oblate patches ranging from 5 to 8 μs. We observe ohmic heating with maximum temperature differences up to tens of kelvins depending on the eccentricity and density of the initial patch influencing the efficiency of plasma reactions in streamer channels.
The Migration Diary of a Knickpoint in a Channelized Stream With a Cohesive Bed
Authors: Papanicolaou A. N. (Thanos) , Thomas John T. , Wilson Christopher G. , Abban Benjamin K. B. , Bettis E. Arthur , Elhakeem Mohamed 
Published: April 2019

AbstractThis paper examines the coevolutionary roles of variable flow features and heterogeneous substrates on knickpoint migration. A conceptual model is used to depict distinct migration mechanisms in a channelized headwater system of a representative intensively managed watershed in the Deep Loess Region of the U.S. Midwest. Throughout this region, entrenched streams have eroded into alluvial‐based strata that are horizontally consistent but vertically heterogeneous. Variable flow in these streams switches between vented conditions, where water shoots from the knickpoint face as an aerated plunging jet, and unvented conditions, where water clings close to its face through suction. These switches affect hydrodynamic mechanisms controlling migration but cannot explain fully observed alternating slow‐fast migration rates. It is hypothesized that vertically heterogeneous strata in entrenched streams, specifically strong‐over‐weak layers, facilitate observed changes in knickpoint migration rates. Preferential erosion of weaker sublayers is thought to trigger other erosional mechanisms to accelerate migration even at low flows. Herein, a migration “diary” documents a representative knickpoint's displacement over time with flow measurements and site stratigraphy. Slower migration occurred from 2006 to 2009 through fluvial erosion of a resistant silt loam cap. From 2009 to 2012, migration accelerated as the knickpoint face reached a critical height through scour. A flow back roller formed, which preferentially eroded a weaker sand sublayer. Undercutting/cantilever failure cycles persisted, causing 30 m of retreat within 2 months (i.e., 62.5% of the total migration over 78 months). Comparisons with established fluvial hydraulics‐based and undercutting/cantilever‐based migration models confirm the hypothesis and importance of both stratified substrates and hydrodynamic controls on knickpoint migration.
A Multivariate AMV Index and Associated Discrepancies Between Observed and CMIP5 Externally Forced AMV
Authors: Yan Xiaoqin , Zhang Rong , Knutson Thomas R. 
Published: April 2019

AbstractAtlantic Multidecadal Variability (AMV) is a multivariate phenomenon. Here for the first time we obtain a multivariate AMV index and associated patterns using Multivariate Empirical Orthogonal Function (MEOF) analysis to explore the multivariate nature of AMV. Coherent multidecadal variability that is unique to the Atlantic is found in the observed MEOF‐extracted AMV, various AMV‐related indices, and an Atlantic Meridional Overturning Circulation fingerprint. When the signal associated with global mean sea surface temperature is removed from both observations and Coupled Model Intercomparison Project Phase 5 (CMIP5) simulations, the residual CMIP5 forced basin‐wide sea surface temperature‐based AMV index disagrees strongly with the observed residual. Only the observed residual basin‐wide sea surface temperature‐based AMV index retains a strong AMV signal. The MEOF approach still extracts a residual CMIP5 forced AMV signal that is unique to the Atlantic, although very different from observations. Our findings suggest that the observed AMV is not dominated by external forcing.
The Effects of Thermal Electrons on Whistler Mode Waves Excited by Anisotropic Hot Electrons: Linear Theory and 2‐D PIC Simulations
Authors: Fan Kai , Gao Xinliang , Lu Quanming , Guo Jun , Wang Shui 
Published: April 2019

AbstractThe wave normal angle of excited whistler waves was previously considered to be controlled by the parallel plasma beta (β∥h) of anisotropic hot electrons, while the effects of thermal electrons were usually neglected. By combining both the linear theoretical and 2‐D particle‐in‐cell (PIC) simulation models, we have investigated the effects of thermal electrons on the whistler anisotropy instability. In the high‐beta (β∥h ≥ 0.025) regime, the wave normal angle of the dominant whistler mode with the largest growth rate is always 0°, which is not affected by thermal electrons, while, its wave frequency and linear growth rate decrease with the density and temperature of thermal electrons. These results are also confirmed by PIC simulations. In the low‐beta (β∥h ≤ 0.025) regime, with the increase of the density and temperature of thermal electrons, the wave normal angle of the dominant whistler mode turns to zero from a large value. This change could be due to the stronger damping caused by thermal electrons for oblique whistler mode, since oblique wave usually has a smaller cyclotron resonant velocity than parallel wave. PIC simulations also show a consistent result, but reproduce a broad magnetic spectrum, even in the case including sufficient thermal electrons. Furthermore, thermal electrons with large parallel velocities are resonantly accelerated in the perpendicular direction, while parts of hot electrons are trapped and accelerated in the parallel direction. Our study suggests that the wave normal angle of whistler mode in the Earth's magnetosphere could be determined by both anisotropic and thermal electrons.
Annual and Semiannual Oscillations of Thermospheric Composition in TIMED/GUVI Limb Measurements
Authors: Yue Jia , Jian Yongxiao , Wang Wenbin , Meier R.R. , Burns Alan , Qian Liying , Jones M. , Wu Dong L. , Mlynczak Martin 
Published: April 2019

AbstractThe Global UltraViolet Imager (GUVI) onboard the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite provides a data set of vertical thermospheric composition (O, N2, and O2 densities) and temperature profiles from 2002–2007. Even though GUVI sampling is limited by orbital constraint, we demonstrated that the GUVI data set can be used to derive the altitude profiles of the amplitudes and phases of annual oscillation (AO) and semiannual oscillation (SAO), thereby providing important constraints on models seeking to explain these features. We performed a seasonal and interannual analysis of GUVI limb O, O2, and N2 densities and volume number density ratio O/N2 at constant pressure levels. These daytime observations of O and O/N2 in the lower thermosphere show a strong AO at midlatitudes and a clear SAO at lower latitudes. The global mean GUVI O/N2 number density ratio shows the AO, with slightly larger values in January than in July and a SAO with O/N2 greater during equinoxes than at the solstices. O and N2 densities on fixed pressure levels in the upper thermosphere are anticorrelated with solar extreme ultraviolet flux. On the other hand, O/N2 is smaller during solar minimum and larger during solar maximum. The thermospheric AO and SAO in composition have a constant phase with altitude throughout the thermosphere.
Auditory sensory memory span for duration is severely curtailed in females with Rett syndrome
Authors: Brima Tufikameni , Molholm Sophie , Molloy Ciara J. , Sysoeva Olga V. , Nicholas Eric , Djukic Aleksandra , Freedman Edward G. , Foxe John J. 
Published: April 2019

AbstractRett syndrome (RTT), a rare neurodevelopmental disorder caused by mutations in the MECP2 gene, is typified by profound cognitive impairment and severe language impairment, rendering it very difficult to accurately measure auditory processing capabilities behaviorally in this population. Here we leverage the mismatch negativity (MMN) component of the event-related potential to measure the ability of RTT patients to decode and store occasional duration deviations in a stream of auditory stimuli. Sensory memory for duration, crucial for speech comprehension, has not been studied in RTT.High-density electroencephalography was successfully recorded in 18 females with RTT and 27 age-matched typically developing (TD) controls (aged 6–22 years). Data from seven RTT and three TD participants were excluded for excessive noise. Stimuli were 1 kHz tones with a standard duration of 100 ms and deviant duration of 180 ms. To assess the sustainability of sensory memory, stimulus presentation rate was varied with stimulus onset asynchronies (SOAs) of 450, 900, and 1800 ms. MMNs with maximum negativity over fronto-central scalp and a latency of 220–230 ms were clearly evident for each presentation rate in the TD group, but only for the shortest SOA in the RTT group. Repeated-measures ANOVA revealed a significant group by SOA interaction. MMN amplitude correlated with age in the TD group only. MMN amplitude was not correlated with the Rett Syndrome Severity Scale. This study indicates that while RTT patients can decode deviations in auditory duration, the span of this sensory memory system is severely foreshortened, with likely implications for speech decoding abilities.
Antidepressants affect gut microbiota and Ruminococcus flavefaciens is able to abolish their effects on depressive-like behavior
Authors: Lukić Iva , Getselter Dmitriy , Ziv Oren , Oron Oded , Reuveni Eli , Koren Omry , Elliott Evan 
Published: April 2019

AbstractAccumulating evidence demonstrates that the gut microbiota affects brain function and behavior, including depressive behavior. Antidepressants are the main drugs used for treatment of depression. We hypothesized that antidepressant treatment could modify gut microbiota which can partially mediate their antidepressant effects. Mice were chronically treated with one of five antidepressants (fluoxetine, escitalopram, venlafaxine, duloxetine or desipramine), and gut microbiota was analyzed, using 16s rRNA gene sequencing. After characterization of differences in the microbiota, chosen bacterial species were supplemented to vehicle and antidepressant-treated mice, and depressive-like behavior was assessed to determine bacterial effects. RNA-seq analysis was performed to determine effects of bacterial treatment in the brain. Antidepressants reduced richness and increased beta diversity of gut bacteria, compared to controls. At the genus level, antidepressants reduced abundances of Ruminococcus, Adlercreutzia, and an unclassified Alphaproteobacteria. To examine implications of the dysregulated bacteria, we chose one of antidepressants (duloxetine) and investigated if its antidepressive effects can be attenuated by simultaneous treatment with Ruminococcus flavefaciens or Adlercreutzia equolifaciens. Supplementation with R. flavefaciens diminished duloxetine-induced decrease in depressive-like behavior, while A. equolifaciens had no such effect. R. flavefaciens treatment induced changes in cortical gene expression, up-regulating genes involved in mitochondrial oxidative phosphorylation, while down-regulating genes involved in neuronal plasticity. Our results demonstrate that various types of antidepressants alter gut microbiota composition, and further implicate a role for R. flavefaciens in alleviating depressive-like behavior. Moreover, R. flavefaciens affects gene networks in the brain, suggesting a mechanism for microbial regulation of antidepressant treatment efficiency.
Evaluation of MEDAG gene expression in papillary thyroid microcarcinoma: associations with histological features, regional lymph node metastasis and prognosis
Authors: Song Yang , Fu Li-jun , Li Hong-ting , Qiu Xin-guang 
Published: April 2019

AbstractPapillary thyroid microcarcinoma accounts﻿ for a large proportion of papillary thyroid carcinoma, especially among new cases. Many PTMC patients have regional lymph node metastasis, with some experiencing recurrence and even death. However, the risk factors and mechanism by which PTMC relates to these factors are unknown. In this study, differentially expressed genes were identified with microarray from The Cancer Genome Atlas, followed by analysis using the Kyoto Encyclopedia of Genes and Genomes. Immunohistochemistry, immunofluorescence, western blot and Oil Red O staining were carried out to evaluate expression levels and functional alterations. Mesenteric Estrogen Dependent Adipogenesis expression was observed in almost all cases of papillary thyroid microcarcinomas, and the location of expression was associated with histological subtype. High expression was correlated with metastasis and poor disease-free survival. Furthermore, the enrichment analysis indicated that Mesenteric Estrogen Dependent Adipogenesis expression may be associated with metabolic reprogramming to influence metastasis and prognosis. These findings contribute to a better understanding of how Mesenteric Estrogen Dependent Adipogenesis affects metastasis and the prognosis of papillary thyroid microcarcinoma patients and suggest that Mesenteric Estrogen Dependent Adipogenesis expression may be a novel prognostic marker in these patients.
Iterative screening methodology enables isolation of strains with improved properties for a FACS-based screen and increased L-DOPA production
Authors: Savitskaya Judy , Protzko Ryan J. , Li Francesca-Zhoufan , Arkin Adam P. , Dueber John E. 
Published: April 2019

AbstractOptimizing microbial hosts for the large-scale production of valuable metabolites often requires multiple mutations and modifications to the host’s genome. We describe a three-round screen for increased L-DOPA production in S. cerevisiae using FACS enrichment of an enzyme-coupled biosensor for L-DOPA. Multiple rounds of screening were enabled by a single build of a barcoded in vitro transposon-mediated disruption library. New background strains for screening were built for each iteration using results from previous iterations. The same in vitro transposon-mediated disruption library was integrated by homologous recombination into new background strains in each round of screening. Compared with creating new transposon insertions in each round, this method takes less time and saves the cost of additional sequencing to characterize transposon insertion sites. In the first two rounds of screening, we identified deletions that improved biosensor compartmentalization and, consequently, improved our ability to screen for L-DOPA production. In a final round, we discovered that deletion of heme oxygenase (HMX1) increases total heme concentration and increases L-DOPA production, using dopamine measurement as a proxy. We further demonstrated that deleting HMX1 may represent a general strategy for P450 function improvement by improving activity of a second P450 enzyme, BM3, which performs a distinct reaction.