bluuebunny/crossref_metadata_2025 huggingface dataset:
𝑞-Bessel functions and Rogers-Ramanujan type identities
Authors: Ismail Mourad , Zhang Ruiming
Published: May 2018

We evaluate

q
q

-Bessel functions at an infinite sequence of points and introduce a generalization of the Ramanujan function and give an extension of the

m
m

-version of the Rogers-Ramanujan identities. We also prove several generating functions for Stieltjes-Wigert polynomials with argument depending on the degree. In addition we give several Rogers-Ramanujan type identities.
Using Bayesian Kriging for Spatial Smoothing in Crop Insurance Rating
Authors: Park Eunchun , Brorsen B. Wade , Harri Ardian
Published: May 2018

Rating insurance policies depends on the probability of events in the tail of a distribution. A method to measure such tail‐related risk based on Extreme Value Theory could potentially improve insurance rating. It is also widely agreed that there is a spatial structure to crop yield distributions. Considering the spatial structure may provide more precisely rated policies. In this context, this research provides two contributions in rating area yield crop insurance. One is to provide a method that fits the tail of crop yield distributions using the Generalized Pareto Distribution (GPD), a member of the family of extreme value distributions that models only the tail of the distribution. The second is to estimate parameters of the distribution using a Bayesian Kriging approach that provides spatial smoothing of GPD parameters. The proposed model provides estimates of the spatial structure across regions such as the maximum distance of the spatial effect. Based on an out‐of‐sample performance game between a private insurance company and the federal agency the proposed model provides considerable improvement, particularly when rating deeper tail probability.
Association Between Change in Central Nocturnal Blood Pressure and Urine Albumin–Creatinine Ratio by a Valsartan/Amlodipine Combination: A CPET Study
Authors: Fujiwara Takeshi , Yano Yuichiro , Hoshide Satoshi , Kanegae Hiroshi , Hashimoto Junichiro , Kario Kazuomi
Published: May 2018

BACKGROUND

We aimed to assess the association of changes in brachial or central nocturnal systolic blood pressure (SBP) with change in urine albumin–creatinine ratio (UACR) by a valsartan/amlodipine combination (80/5 mg) therapy in hypertensive patients.

METHODS

Twenty-three patients (age range, 47–78 years; mean, 68.0 years; 35% men, 65% with chronic kidney disease) with clinic brachial BP ≥140/90 mm Hg were treated with valsartan/amlodipine combination therapy for 16 weeks. At baseline and 16 weeks later, we measured brachial and central nocturnal SBP using an oscillometric Mobil-O-Graph device and UACR by spot urine in 23 patients.

RESULTS

The changes in brachial nocturnal SBP (r = 0.445, P = 0.033) and those in central nocturnal SBP (r = 0.616, P = 0.002) were significantly associated with change in UACR by intervention. In multivariable-adjusted multiple regression analyses including changes in both brachial and central nocturnal SBP jointly, only central nocturnal SBP change retained a statistically significant association with change in UACR (β = 0.919, P = 0.020).

CONCLUSIONS

Lowering central nocturnal SBP by a valsartan/amlodipine combination therapy was associated with reduction of UACR, independently of brachial nocturnal SBP reduction. Central nocturnal SBP may be a therapeutic target to protect the kidney. A larger scale interventional study will be needed to confirm the kidney protection conferred by lowering central nocturnal SBP.

CLINICAL TRIALS REGISTRATION

Trial Number UMIN000013519.
RIFRAF: a frame-resolving consensus algorithm
Authors: Eren Kemal , Murrell Ben
Published: May 2018

Motivation

Protein coding genes can be studied using long-read next generation sequencing. However, high rates of indel sequencing errors are problematic, corrupting the reading frame. Even the consensus of multiple independent sequence reads retains indel errors. To solve this problem, we introduce Reference-Informed Frame-Resolving multiple-Alignment Free template inference algorithm (RIFRAF), a sequence consensus algorithm that takes a set of error-prone reads and a reference sequence and infers an accurate in-frame consensus. RIFRAF uses a novel structure, analogous to a two-layer hidden Markov model: the consensus is optimized to maximize alignment scores with both the set of noisy reads and with a reference. The template-to-reads component of the model encodes the preponderance of indels, and is sensitive to the per-base quality scores, giving greater weight to more accurate bases. The reference-to-template component of the model penalizes frame-destroying indels. A local search algorithm proceeds in stages to find the best consensus sequence for both objectives.

Results

Using Pacific Biosciences SMRT sequences from an HIV-1 env clone, NL4-3, we compare our approach to other consensus and frame correction methods. RIFRAF consistently finds a consensus sequence that is more accurate and in-frame, especially with small numbers of reads. It was able to perfectly reconstruct over 80% of consensus sequences from as few as three reads, whereas the best alternative required twice as many. RIFRAF is able to achieve these results and keep the consensus in-frame even with a distantly related reference sequence. Moreover, unlike other frame correction methods, RIFRAF can detect and keep true indels while removing erroneous ones.

Availability and implementation

RIFRAF is implemented in Julia, and source code is publicly available at https://github.com/MurrellGroup/Rifraf.jl.

Supplementary information

Supplementary data are available at Bioinformatics online.
MODE-TASK: large-scale protein motion tools
Authors: Ross Caroline , Nizami Bilal , Glenister Michael , Sheik Amamuddy Olivier , Atilgan Ali Rana , Atilgan Canan , Tastan Bishop Özlem
Published: May 2018

MODE-TASK, a novel and versatile software suite, comprises Principal Component Analysis, Multidimensional Scaling, and t-Distributed Stochastic Neighbor Embedding techniques using Molecular Dynamics trajectories. MODE-TASK also includes a Normal Mode Analysis tool based on Anisotropic Network Model so as to provide a variety of ways to analyse and compare large-scale motions of protein complexes for which long MD simulations are prohibitive. Beside the command line function, a GUI has been developed as a PyMOL plugin.

Availability and implementation

MODE-TASK is open source, and available for download from https://github.com/RUBi-ZA/MODE-TASK. It is implemented in Python and C++. It is compatible with Python 2.x and Python 3.x and can be installed by Conda.

Supplementary information

Supplementary data are available at Bioinformatics online.
GateFinder: projection-based gating strategy optimization for flow and mass cytometry
Authors: Aghaeepour Nima , Simonds Erin F , Knapp David J H F , Bruggner Robert V , Sachs Karen , Culos Anthony , Gherardini Pier Federico , Samusik Nikolay , Fragiadakis Gabriela K , Bendall Sean C , Gaudilliere Brice , Angst Martin S , Eaves Connie J , Weiss William A , Fantl Wendy J , Nolan Garry P
Published: May 2018

Motivation

High-parameter single-cell technologies can reveal novel cell populations of interest, but studying or validating these populations using lower-parameter methods remains challenging.

Results

Here, we present GateFinder, an algorithm that enriches high-dimensional cell types with simple, stepwise polygon gates requiring only two markers at a time. A series of case studies of complex cell types illustrates how simplified enrichment strategies can enable more efficient assays, reveal novel biomarkers and clarify underlying biology.

Availability and implementation

The GateFinder algorithm is implemented as a free and open-source package for BioConductor: https://nalab.stanford.edu/gatefinder.

Supplementary information

Supplementary data are available at Bioinformatics online.
Using multivariate mixed-effects selection models for analyzing batch-processed proteomics data with non-ignorable missingness
Authors: Wang Jiebiao , Wang Pei , Hedeker Donald , Chen Lin S
Published: May 2018

In quantitative proteomics, mass tag labeling techniques have been widely adopted in mass spectrometry experiments. These techniques allow peptides (short amino acid sequences) and proteins from multiple samples of a batch being detected and quantified in a single experiment, and as such greatly improve the efficiency of protein profiling. However, the batch-processing of samples also results in severe batch effects and non-ignorable missing data occurring at the batch level. Motivated by the breast cancer proteomic data from the Clinical Proteomic Tumor Analysis Consortium, in this work, we developed two tailored multivariate MIxed-effects SElection models (mvMISE) to jointly analyze multiple correlated peptides/proteins in labeled proteomics data, considering the batch effects and the non-ignorable missingness. By taking a multivariate approach, we can borrow information across multiple peptides of the same protein or multiple proteins from the same biological pathway, and thus achieve better statistical efficiency and biological interpretation. These two different models account for different correlation structures among a group of peptides or proteins. Specifically, to model multiple peptides from the same protein, we employed a factor-analytic random effects structure to characterize the high and similar correlations among peptides. To model biological dependence among multiple proteins in a functional pathway, we introduced a graphical lasso penalty on the error precision matrix, and implemented an efficient algorithm based on the alternating direction method of multipliers. Simulations demonstrated the advantages of the proposed models. Applying the proposed methods to the motivating data set, we identified phosphoproteins and biological pathways that showed different activity patterns in triple negative breast tumors versus other breast tumors. The proposed methods can also be applied to other high-dimensional multivariate analyses based on clustered data with or without non-ignorable missingness.
Valuations on Banach Lattices
Authors: Tradacete Pedro , Villanueva Ignacio
Published: May 2018

We provide a general framework for the study of valuations on Banach lattices. This complements and expands several recent works about valuations on function spaces, including $L_p(\mu )$, Orlicz spaces, and spaces $C(K)$ of continuous functions on a compact Hausdorff space. In particular, we study decomposition properties, boundedness, and integral representation of continuous valuations.
Lattice Simplices with a Fixed Positive Number of Interior Lattice Points: A Nearly Optimal Volume Bound
Authors: Averkov Gennadiy , Krümpelmann Jan , Nill Benjamin
Published: May 2018

We give an explicit upper bound on the volume of lattice simplices with fixed positive number of interior lattice points. The bound differs from the conjectural sharp upper bound only by a linear factor in the dimension. This improves significantly upon the previously best results by Pikhurko from 2001.
Sharp Isoperimetric Inequalities for Small Volumes in Complete Noncompact Riemannian Manifolds of Bounded Geometry Involving the Scalar Curvature
Authors: Nardulli Stefano , Osorio Acevedo Luis Eduardo
Published: May 2018

We provide an isoperimetric comparison theorem for small volumes in an $n$-dimensional Riemannian manifold $(M^n,g)$ with $C^3$ bounded geometry in a suitable sense involving the scalar curvature function. Under $C^3$ bounds of the geometry, if the supremum of scalar curvature function $S_g<n(n-1)k_0$ for some $k_0\in \mathbb{R}$, then for small volumes the isoperimetric profile of $(M^n,g)$ is less then or equal to the isoperimetric profile of the complete simply connected space form of constant sectional curvature $k_0$. This work generalizes Theorem $2$ of [12] in which the same result was proved in the case where $(M^n, g)$ is assumed to be compact. As a consequence of our result we give an asymptotic expansion in Puiseux series up to the 2nd nontrivial term of the isoperimetric profile function for small volumes, generalizing our earlier asymptotic expansion [29]. Finally, as a corollary of our isoperimetric comparison result, it is shown that for small volumes the Aubin–Cartan–Hadamard’s conjecture is true in any dimension $n$ in the special case of manifolds with $C^3$ bounded geometry, and $S_g<n(n-1)k_0$. Two different intrinsic proofs of the fact that an isoperimetric region of small volume is of small diameter. The 1st under the assumption of mild bounded geometry, that is, positive injectivity radius and Ricci curvature bounded below. The 2nd assuming the existence of an upper bound of the sectional curvature, positive injectivity radius, and a lower bound of the Ricci curvature.
Equations for Some Nilpotent Varieties
Authors: Johnson Ben , Sommers Eric
Published: May 2018

Let ${\mathcal{O}}$ be a Richardson nilpotent orbit in a simple Lie algebra $\mathfrak{g}$ of rank $n$ over $\mathbb C$, induced from a Levi subalgebra whose $s$ simple roots are orthogonal, short roots. The main result of the paper is a description of a minimal set of generators of the ideal defining $\overline{\mathcal{O}}$ in $S \mathfrak{g}^{\ast }$. In such cases, the ideal is generated by bases of either one or two copies of the representation whose highest weight is the dominant short root, along with $n-s$ fundamental invariants of $S \mathfrak{g}^{\ast }$. This extends Broer’s result for the subregular nilpotent orbit, which is the case of $s=1$. Along the way we give another proof of Broer’s result that $\overline{\mathcal{O}}$ is normal. We also prove a result relating a property of the invariants of $S \mathfrak{g}^{\ast }$ to the following question: when does a copy of the adjoint representation in $S \mathfrak{g}^{\ast }$ belong to the ideal in $S \mathfrak{g}^{\ast }$ generated by another copy of the adjoint representation together with the invariants of $S \mathfrak{g}^{\ast }$?
Deformation of Dirac Structures via L∞ Algebras
Authors: Gualtieri Marco , Matviichuk Mykola , Scott Geoffrey
Published: May 2018

The deformation theory of a Dirac structure is controlled by a differential graded Lie algebra that depends on the choice of an auxiliary transversal Dirac structure; if the transversal is not involutive, one obtains an $L_\infty $ algebra instead. We develop a simplified method for describing this $L_\infty $ algebra and use it to prove that the $L_\infty $ algebras corresponding to different transversals are canonically $L_\infty $–isomorphic. In some cases, this isomorphism provides a formality map, as we show in several examples including (quasi)-Poisson geometry, Dirac structures on Lie groups, and Lie bialgebras. Finally, we apply our result to a classical problem in the deformation theory of complex manifolds; we provide explicit formulas for the Kodaira–Spencer deformation complex of a fixed small deformation of a complex manifold, in terms of the deformation complex of the original manifold.
A systematic assessment of the availability and clinical drug information coverage of machine-readable clinical drug data sources for building knowledge translation products
Authors: Grandy Catherine Anne , Donnan Jennifer R , Peddle Justin T , Romme Kristen , Kim Satpyul , Gamble John-Michael
Published: May 2018

Objective

To identify and describe clinical drug data sources that have the potential to serve as a repository of information for developing drug knowledge translation products.

Methods

Two reviewers independently screened citations from PubMed and Embase, websites from the web search engine Google, and references from selected journals. Publicly licensed or non-proprietary data sources containing clinical drug information accessible in a machine-readable format were eligible. Data sources were assessed for their coverage across 18 pre-specified domains and 74 elements of clinical drug information.

Results

Of the 3369 unique citations or webpages screened, 44 drug information data sources were identified. Of these, 22 data sources met the study inclusion criteria. There was a mean of 4.5 (SD = 5.19) domains covered by each source and a mean of 10.9 (SD = 18) elements covered by each source. None of the data sources covered all domains and eight elements were not addressed by any source. All of the data sources identified by the study are government or academic databases.

Conclusion

Our study demonstrated the availability of machine-readable clinical drug data that could help facilitate the creation of novel drug knowledge translation products. However, we identified clinical content gaps in the available non-proprietary drug information sources. Further evaluation of the quality of each data source would be necessary prior to incorporating these sources into any knowledge translation products intended for clinical use.
On the nature of long-period dwarf novae with rare and low-amplitude outbursts
Authors: Kimura Mariko , Kato Taichi , Maehara Hiroyuki , Ishioka Ryoko , Monard Berto , Nakajima Kazuhiro , Stone Geoff , Pavlenko Elena P , Antonyuk Oksana I , Pit Nikolai V , Sosnovskij Aleksei A , Katysheva Natalia , Richmond Michael , Michel Raúl , Matsumoto Katsura , Kojiguchi Naoto , Sugiura Yuki , Tei Shihei , Yamamura Kenta , Cook Lewis M , Sabo Richard , Miller Ian , Goff William , Kiyota Seiichiro , Shugarov Sergey Yu , Golysheva Polina , Vozyakova Olga , Brincat Stephen M , Itoh Hiroshi , Tordai Tamás , Littlefield Colin , Pickard Roger D , Tanabe Kenji , Kinugasa Kenzo , Honda Satoshi , Taguchi Hikaru , Hashimoto Osamu , Nogami Daisaku
Published: May 2018

There are several peculiar long-period dwarf-nova-like objects that show rare, low-amplitude outbursts with highly ionized emission lines; 1SWASP J162117+441254, BD Pav, and V364 Lib are among them. Some researchers even doubt whether 1SWASP J1621 and V364 Lib have the same nature as normal dwarf novae. We studied the peculiar outbursts in these three objects via our optical photometry and spectroscopy, and performed numerical modeling of their orbital variations to investigate their properties. We found that their outbursts lasted for a long interval (a few tens of days), and that slow rises in brightness were commonly observed during the early stage of their outbursts. Our analyses and numerical modeling suggest that 1SWASP J1621 has a very high inclination, close to 90°, plus a faint hot spot. Although BD Pav seems to have a slightly lower inclination (∼75°), the other properties are similar to those in 1SWASP J1621. On the other hand, V364 Lib appears to have a massive white dwarf, a hot companion star, and a low inclination (∼35°). In addition, these three objects possibly have a low transfer rate and/or large disks originating from the long orbital periods. We found that these properties of the three objects can explain their infrequent and low-amplitude outbursts within the context of the disk instability model in normal dwarf novae without a strong magnetic field. In addition, we suggest that the highly ionized emission lines in outburst are observed due to a high inclination and/or a massive white dwarf. More instances of this class of object may be unrecognized, since their unremarkable outbursts can be easily overlooked.
Verticillium Wilt on Fiber Flax: Symptoms and Pathogen Development In Planta
Authors: Blum Adrien , Bressan Mélanie , Zahid Abderrakib , Trinsoutrot-Gattin Isabelle , Driouich Azeddine , Laval Karine
Published: May 2018

Fiber flax (Linum usitatissimum L.), an important crop in Normandy (France), is increasingly affected by Verticillium wilt caused by the soilborne fungus Verticillium dahliae. This disease leads to nonnegligible yield losses and depreciated fibers that are consequently difficult to upgrade. Verticillium wilt is a major threat to a broad range of agriculture. In this study, susceptible fiber flax cultivar Adélie was infected by VdLu01 (isolated from fiber flax, this study) or green fluorescent protein-tagged VdLs17 (transformed and provided by the department of Plant Pathology, University of California, Davis). Between 3 and 4 weeks postinoculation, wilting symptoms on leaves were first observed, with acropetal growth during the following weeks. Pathogen development was tracked by confocal laser-scanning microscopy during the asymptomatic and symptomatic stages. First, conidia germination led to the development of hyphae on root epidermis; more particularly, on the zone of cell differentiation and around emerging lateral roots, while the zone of cell division and the root tip were free of the pathogen. At 3 days postinoculation, the zone of cell differentiation and lateral roots were embedded into a fungal mass. Swelling structures such as appressoria were observed at 1 week postinoculation. At 2 weeks postinoculation and onward, the pathogen had colonized xylem vessels in roots, followed by the stem and, finally, leaves during the symptomatic stage. Additionally, observations of infected plants after retting in the field revealed microsclerotia embedded inside the bast fiber bundle, thus potentially contributing to weakening of fiber. All of these results provide a global account of V. dahliae development when infecting fiber flax.
Measuring Mindsets and Achievement Goal Motivation: A Validation Study of Three Instruments
Authors: Cook David A. , Gas Becca L. , Artino Anthony R.
Published: May 2018

Purpose

To evaluate the validity of scores from three instruments measuring achievement goal motivation-related constructs: a shortened version of Dweck’s Implicit Theories of Intelligence Scale (ITIS-S), measuring incremental and entity mindsets; Elliot’s Achievement Goal Questionnaire–Revised (AGQ-R), measuring mastery-approach, mastery-avoidance, performance-approach, and performance-avoidance achievement goals; and Midgley’s Patterns of Adaptive Learning Scales (PALS), measuring mastery, performance-approach, and performance-avoidance achievement goals.

Method

High school students participating in a medical simulation training activity in May 2017 completed each instrument. The authors evaluated internal structure using reliability and factor analysis and relations with other variables using the multitrait–multimethod matrix.

Results

There were 178 participants. Internal consistency reliability (Cronbach alpha) was > 0.70 for all subscores. Confirmatory factor analysis of ITIS-S scores demonstrated good model fit. Confirmatory factor analysis of AGQ-R scores demonstrated borderline fit; exploratory factor analysis suggested a three-domain model (approach, mastery-avoidance, performance-avoidance). Confirmatory factor analysis of PALS scores also demonstrated borderline fit; exploratory factor analyses suggested consistent distinction between mastery and performance goals but inconsistent distinction between performance-approach and performance-avoidance goals. Correlations among AGQ-R and PALS scores were large for mastery (r = 0.72) and moderate for performance (≥ 0.45) domains; correlations among incremental and mastery scores were moderate (≥ 0.34). Contrary to expectations, correlations between entity and performance scores were negligible. Correlations between conceptually unrelated domains were small or negligible.

Conclusions

All instrument scores had good internal consistency and generally appropriate relations with other variables, but empirically determined domain structures did not consistently match theory.
Academic Health Centers and Medicaid: Advance or Retreat?
Authors: Henderson Mark C. , Kizer Kenneth W. , Kravitz Richard L.
Published: May 2018

The expansion of Medicaid under the Affordable Care Act has strained the capacity of many academic health centers (AHCs) to deliver primary and specialty care to this traditionally underserved population. The authors, longtime faculty members in the University of California, Davis Health (UCDH) system, discuss the challenges of UCDH’s participation in Medi-Cal, the nation’s largest Medicaid program, and their institution’s controversial decision in 2015 to withdraw from its last Medi-Cal primary care contract, which has had untoward effects on UCDH’s social and educational missions. The authors call on AHCs to leverage their considerable intellectual and human capital as well as their focus on education and research to aggressively pursue innovative models of high-value primary care for underserved populations in their local communities, highlighting several recent successful examples of such programs. The UCDH experience has implications for other AHCs grappling with the financial realities of an increasingly competitive, value-based health care marketplace and the inherent difficulty in balancing educational, research, patient care, and social or community service missions.
A Conceptual Model for Understanding Academic Physicians’ Performances of Identity: Findings From the University of Utah
Authors: Chow Candace J. , Byington Carrie L. , Olson Lenora M. , Ramirez Karl Paulo Garcia , Zeng Shiya , López Ana María
Published: May 2018

Purpose

To explore how academic physicians perform social and professional identities and how their personal experiences inform professional identity formation.

Method

Semistructured interviews and observations were conducted with 25 academic physicians of diverse gender and racial/ethnic backgrounds at the University of Utah School of Medicine from 2015 to 2016. Interviews explored the domains of social identity, professional identity, and relationships with patients and colleagues. Patient interactions were observed. Interviews and observations were audio-recorded, transcribed, and analyzed using grounded theory.

Results

Three major themes emerged: Physicians’ descriptions of identity differed based on social identities, as women and racially/ethnically minoritized participants linked their gender and racial/ethnic identities, respectively, to their professional roles more than men and white, non-Latino/a participants; physicians’ descriptions of professional practice differed based on social identities, as participants who associated professional practices with personal experiences often drew from events connected to their minoritized identities; and physicians’ interactions with patients corresponded to their self-described actions.

Conclusions

Professional identity formation is an ongoing process, and the negotiation of personal experiences is integral to this process. This negotiation may be more complex for physicians with minoritized identities. Implications for medical education include providing students, trainees, and practicing physicians with intentional opportunities for reflection and instruction on connecting personal experiences and professional practice.
Value-Added Activities in Medical Education: A Multisite Survey of First- and Second-Year Medical Students’ Perceptions and Factors Influencing Their Potential Engagement
Authors: Leep Hunderfund Andrea N. , Starr Stephanie R. , Dyrbye Liselotte N. , Gonzalo Jed D. , George Paul , Miller Bonnie M. , Morgan Helen K. , Hoffman Ari , Baxley Elizabeth G. , Allen Bradley L. , Fancher Tonya L. , Mandrekar Jay , Skochelak Susan E. , Reed Darcy A.
Published: May 2018

Purpose

To describe attitudes of first- and second-year U.S. medical students toward value-added medical education, assess their self-reported desire to participate in value-added activities, and identify potentially modifiable factors influencing their engagement.

Method

The authors conducted a cross-sectional survey of first- and second-year students at nine U.S. medical schools in 2017. Survey items measured students’ attitudes toward value-added medical education (n = 7), desire to participate in value-added activities (n = 20), and factors influencing potential engagement (n = 18).

Results

Of 2,670 students invited to participate, 1,372 (51%) responded. Seventy-six percent (1,043/1,368) moderately or strongly agreed they should make meaningful contributions to patient care. Students’ desire to participate was highest for patient care activities approximating those traditionally performed by physicians, followed by systems improvement activities and lowest for activities not typically performed by physicians. Factors increasing desire to participate included opportunities to interact with practicing physicians (1,182/1,244; 95%), patients (1,177/1,246; 95%), and residents or fellows (1,166/1,246; 94%). Factors decreasing desire to participate included making changes to the health care system (365/1,227; 30%), interacting with patients via phone or electronic communication (410/1,243; 33%), and lack of curricular time (634/1,233; 51%).

Conclusions

First- and second-year medical students agree they should add value to patient care, but their desire to participate in value-added activities varies depending on the nature of the tasks. Medical schools may be able to increase students’ desire to participate by enabling face-to-face interactions with patients, embedding students in health care teams, and providing dedicated curricular time.
Sexual Harassment in Medical Schools: The Challenge of Covert Retaliation as a Barrier to Reporting
Authors: Binder Renee , Garcia Paul , Johnson Bonnie , Fuentes-Afflick Elena
Published: May 2018

Although Title IX, the federal law prohibiting sexual harassment in educational institutions, was enacted in 1972, sexual harassment continues to be distressingly common in medical training. In addition, many women who experience sexual harassment do not report their experiences to authorities within the medical school.

In this article, the authors review the literature on the prevalence of sexual harassment in medical schools since Title IX was enacted and on the cultural and legal changes that have occurred during that period that have affected behaviors. These changes include decreased tolerance for harassing behavior; increased legal responsibility assigned to institutions; and a significant increase in the number of female medical students, residents, and faculty. The authors then discuss persisting barriers to reporting sexual harassment, including fears of reprisals and retaliation, especially covert retaliation. They define covert retaliation as vindictive comments made by a person accused of sexual harassment about his or her accuser in a confidential setting, such as a grant review, award selection, or search committee.

The authors conclude by highlighting institutional and organizational approaches to decreasing sexual harassment and overt retaliation, and they propose other approaches to decreasing covert retaliation. These initiatives include encouraging senior faculty members to intervene and file bystander complaints when they witness inappropriate comments or behaviors as well as group reporting when multiple women are harassed by the same person.
Effects of Amplification and Hearing Aid Experience on the Contribution of Specific Frequency Bands to Loudness
Authors: Thrailkill Katie M. , Brennan Marc A. , Jesteadt Walt
Published: May 2018

Objectives:

The primary aim of this study is to describe the effect of hearing aid amplification on the contribution of specific frequency bands to overall loudness in adult listeners with sensorineural hearing loss (SNHL). Results for listeners with SNHL were compared with results for listeners with normal hearing (NH) to evaluate whether amplification restores the normal perception of loudness for broadband sound. A secondary aim of this study is to determine whether the loudness perception of new hearing aid users becomes closer to normal over the first few months of hearing aid use. It was hypothesized that amplification would cause the high-frequency bands to contribute most to the perception of loudness and that this effect might decrease as new hearing aid users adapt to amplification.

Design:

In experiment 1, 8 adult listeners with SNHL completed a two-interval forced-choice loudness task in unaided and aided conditions. A control group of 7 listeners with NH completed the task in the unaided condition only. Stimuli were composed of seven summed noise bands whose levels were independently adjusted between presentations. During a trial, two stimuli were presented, and listeners determined the louder one. The correlation between the difference in levels for a given noise band on every trial and the listener’s response was calculated. The resulting measure is termed the perceptual weight because it provides an estimate of the relative contribution of a given frequency region to overall loudness. In experiment 2, a separate group of 6 new hearing aid users repeated identical procedures on 2 sessions separated by 12 weeks.

Results:

Results for listeners with SNHL were similar in experiments 1 and 2. In the unaided condition, perceptual weights were greatest for the low-frequency bands. In the aided condition, perceptual weights were greatest for the high-frequency bands. On average, the aided perceptual weights for listeners with SNHL for high-frequency bands were greater than the unaided weights for listeners with NH. In experiment 2, hearing aid experience did not have a significant effect on perceptual weights.

Conclusions:

The high frequencies seem to dominate loudness perception in listeners with SNHL using hearing aids as they do in listeners with NH. However, the results suggest that amplification causes high frequencies to have a larger contribution to overall loudness compared with listeners with NH. The contribution of the high frequencies to loudness did not change after an acclimatization period for the first-time hearing aid users.
Course and Contributors to Back Pain in Middle-aged Women Over 9 Years
Authors: Brady Sharmayne R.E. , Hussain Sultana Monira , Brown Wendy J. , Heritier Stephane , Wang Yuanyuan , Teede Helena , Urquhart Donna M. , Cicuttini Flavia M.
Published: May 2018

Study Design.

Community-based, cohort study.

Objective.

Our aim was to determine the course of back pain in middle-aged women over a 9-year period, and assess whether obesity and physical inactivity are associated with more frequent back pain.

Summary of Background Data.

Back pain is the leading cause of disability worldwide. With minimal effective therapies and rising financial burden, identifying modifiable risk factors remains a key priority.

Methods.

The Australian Longitudinal Study on Women's Health is a cohort study of community-based, middle-aged women who completed questionnaires every 3 years between 2004 and 2013. Approximately, 10,530 women completed the survey in 2004 (mean age 55.5 yrs), and 9020 completed follow-up 9 years later. Self-reported data on back pain in the last 12 months and other sociodemographic factors were collected at all four surveys. ‘Frequent back pain’ was defined as back pain reported at ≥ three surveys.

Results.

Back pain was common and persistent, with 48% having back pain in ≥ three out of four surveys. Baseline obesity (relative risk [RR] 1.18, 95% confidence interval [CI] 1.12–1.25), lack of vigorous physical activity (RR 1.17, 95% CI 1.10–1.25), depressive symptoms (RR 1.40, 95% CI 1.33–1.47), and low-education status (RR 1.17, 95% CI 1.12–1.24), were independently associated with an increased risk of frequent back pain (all P < 0.001). Overall, 28% of the risk of frequent back pain could be attributed to these factors, equating to one extra case of frequent back pain for every five women with depressive symptoms, for every 11 obese women, for every 12 women with low-education status, and for every 13 women who do not do vigorous physical activity, at baseline.

Conclusion.

Obesity, depressive symptoms, low-education status, and lack of vigorous physical activity are associated with higher risk of frequent back pain over the following 9 years among women in their mid-50 s. Targeting these risk factors may lessen the burden of back pain.

Level of Evidence: 2
Efficacy and Safety of Full-endoscopic Decompression via Interlaminar Approach for Central or Lateral Recess Spinal Stenosis of the Lumbar Spine
Authors: Lee Chang-Hyun , Choi Miyoung , Ryu Dal Sung , Choi Il , Kim Chi Heon , Kim Hyeun Sung , Sohn Moon-Jun
Published: May 2018

Study Design.

A meta-analysis of five retrospective cohort studies.

Objective.

The aim of the study was to delineate the efficacy and safety of full-endoscopic decompression via the interlaminar approach for central or lateral recess spinal stenosis of the lumbar spine using a meta-analysis.

Summary of Background Data.

The paradigm of spinal endoscopy is shifting from treatment of soft disc herniation to that of lumbar spinal stenosis. Technical advancements have enabled full-endoscopic decompression in spinal stenosis surgery. There is few strong evidence supporting this surgical technique, and clinicians usually rely on their own opinions and experiences.

Methods.

A systematic search of electronic databases, including PubMed, EMBASE, Cochrane Library, Web of science, and KoreaMed, up to August 2017 was performed to identify studies concerning full-endoscopic decompression via the interlaminar approach for lumbar spinal stenosis. Changes in clinical outcomes [Oswestry Disability Index (ODI) and Visual Analog Scales (VAS) for back and leg pain] were compared with the minimal clinically important difference (MCID) for each item. We then calculated the mean differences and 95% confidence intervals (95% CIs) using random-effects models.

Results.

We included data from five studies involving 156 patients at 6- and 12-month follow-ups. The majority of enrolled papers included patients with neurogenic claudication due to central stenosis refractory to conservative management and excluded patients with significant instability or previous surgery. The overall mean difference of patients with ODI and VAS scores for leg and back pain exceeded the criteria for MCID. ODI scores improved by 41.71 (95% CI, 39.80–43.62) after the surgery, which was twice the MCID. The VAS leg and back pain scores improved by 5.95 (95% CI, 5.70–6.21) and 4.22 (95% CI, 3.88–4.56), respectively, indicating statistically significant improvement over the MCID.

Conclusion.

Successful clinical outcomes can be achieved with full-endoscopic decompression via the interlaminar approach for lumbar central spinal stenosis in patients for the defined indications.

Level of Evidence: 2
Adjacent Disc Degeneration After Lumbar Total Disc Replacement or Nonoperative Treatment
Authors: Furunes Håvard , Hellum Christian , Espeland Ansgar , Brox Jens Ivar , Småstuen Milada Cvancarova , Berg Linda , Storheim Kjersti
Published: May 2018

Study Design.

A randomized controlled multicenter trial with 8-year follow-up.

Objective.

The aim of this study was to assess the long-term development of adjacent disc degeneration (ADD) after lumbar total disc replacement (TDR) or nonoperative treatment, and to analyze the association between ADD development and clinical outcome.

Summary of Background Data.

TDR was introduced as a motion-preserving alternative to spinal fusion, which has been reported to increase the risk of ADD. However, ADD may develop naturally regardless of any surgery, and no randomized study has assessed the long-term development of ADD after TDR versus nonoperative treatment.

Methods.

The study included 126 of the 173 patients with chronic low back pain (LBP) originally included in a randomized study comparing TDR with multidisciplinary rehabilitation. Magnetic resonance imaging (MRI) of the lumbar spine was performed before treatment and at 8-year follow-up. ADD was categorized as increased or not increased based on an evaluation of Modic changes, disc height reduction, disc contour, herniation size, nucleus pulposus signal, and posterior high intensity zones. We used a χ2 test or a Fisher exact test to compare crude proportions, and multiple linear regressions to analyze the association between increased ADD (yes/no) and change in Oswestry Disability Index (ODI) from pre-treatment to follow-up.

Results.

ADD increased (for at least one ADD variable) in 23 of 57 patients (40%) treated nonoperatively, and 29 of 69 patients (42%) treated with TDR (P = 0.86). We found no significant associations between ADD increase and the change in ODI.

Conclusion.

Increased ADD occurred with similar frequency after TDR and after nonoperative treatment, and was not related to the clinical outcome at 8-year follow-up.

Level of Evidence: 1
Clinical Impact and Economic Burden of Hospital-Acquired Conditions Following Common Surgical Procedures
Authors: Horn Samantha R. , Liu Tiffany C. , Horowitz Jason A. , Oh Cheongeun , Bortz Cole A. , Segreto Frank A. , Vasquez-Montes Dennis , Steinmetz Leah M. , Deflorimonte Chloe , Vira Shaleen , Diebo Bassel G. , Neuman Brian J. , Raad Micheal , Sciubba Daniel M. , Lafage Renaud , Lafage Virginie , Hassanzadeh Hamid , Passias Peter G.
Published: May 2018

Study Design.

Retrospective review of prospectively collected data.

Objective.

To assess the clinical impact and economic burden of the three most common hospital-acquired conditions (HACs) that occur within 30-day postoperatively for all spine surgeries and to compare these rates with other common surgical procedures.

Summary of Background Data.

HACs are part of a non-payment policy by the Centers for Medicare and Medicaid Services and thus prompt hospitals to improve patient outcomes and safety.

Methods.

Patients more than 18 years who underwent elective spine surgery were identified in American College of Surgeons’ National Surgical Quality Improvement Program (ACS-NSQIP) database from 2005 to 2013. Primary outcomes were cost associated with the occurrence of three most common HACs. Cost associated with HAC occurrence derived from the PearlDiver database.

Results.

Ninety thousand five hundred fifty one elective spine surgery patients were identified, where 3021 (3.3%) developed at least one HAC. Surgical site infection (SSI) was the most common HAC (1.4%), then urinary tract infection (UTI) (1.3%) and venous thromboembolism (VTE) (0.8%). Length of stay (LOS) was longer for patients who experienced a HAC (5.1 vs. 3.2 d, P < 0.001). When adjusted for age, sex, and Charlson Comorbidity Index, LOS was 1.48 ± 0.04 days longer (P < 0.001) and payments were $8893 ± $148 greater (P < 0.001) for patients with at least one HAC. With the exception of craniotomy, patients undergoing common procedures with HAC had increased LOS and higher payments (P < 0.001). Adjusted additional LOS was 0.44 ± 0.02 and 0.38 ± 0.03 days for total knee arthroplasty and total hip arthroplasty, and payments were $1974 and $1882 greater. HACs following hip fracture repair were associated with 1.30 ± 0.11 days LOS and $4842 in payments (P < 0.001). Compared with elective spine surgery, only bariatric and cardiothoracic surgery demonstrated greater adjusted additional payments for patients with at least one HAC ($9975 and $10,868, respectively).

Conclusion.

HACs in elective spine surgery are associated with a substantial cost burden to the health care system. When adjusted for demographic factors and comorbidities, average LOS is 1.48 days longer and episode payments are $8893 greater for patients who experience at least one HAC compared with those who do not.

Level of Evidence: 3
Inappropriate Antibiotic Prescribing for Acute Bronchitis in Children and Impact on Subsequent Episodes of Care and Treatment
Authors: Morgan Jake R. , Carey Kathleen M. , Barlam Tamar F. , Christiansen Cindy L. , Drainoni Mari-Lynn
Published: May 2018

Background:

To examine whether inappropriate antibiotic treatment for an initial bout of acute bronchitis in childhood affects patterns of future healthcare utilization and antibiotic prescribing.

Methods:

We conducted a retrospective analysis of children with at least 1 acute bronchitis episode, defined as the 14-day period after an acute bronchitis visit, born in 2008 and followed through 2015 in a nationally representative commercial claims database. We predicted the likelihood of returning for a subsequent acute bronchitis episode, and being prescribed an antibiotic as part of that episode, as a function of whether or not the child was prescribed an antibiotic as part of the first acute bronchitis episode controlling for patient, provider and practice characteristics.

Results:

Children prescribed an antibiotic as part of their initial acute bronchitis episode were more likely both to have a subsequent acute bronchitis episode (hazard ratio = 1.23; 95% confidence interval: 1.17–1.30) and to be prescribed an antibiotic as part of that second episode (hazard ratio = 2.13; 95% confidence interval: 1.99–2.28) compared with children who were not prescribed as part of their first episode. Children diagnosed with asthma were more likely to experience a second visit for acute bronchitis, but less likely to receive an antibiotic as part of that second episode.

Conclusions:

Inappropriate antibiotic prescribing for a child’s initial acute bronchitis episode of care predicted likelihood of subsequent acute bronchitis episodes and antibiotic prescriptions. Providers should consider the downstream effect of inappropriate antibiotic prescribing for acute bronchitis in childhood.
Spinal Tuberculosis in Young HIV-exposed Infants
Authors: Manjate Nádia , Ventura Joyce , Nhassengo Cristina , Navaia Ajunta , João Piedade , Elias Beatriz , Buck W. Chris
Published: May 2018

The presentation of congenital tuberculosis (TB) is varied, with frequent extrapulmonary disease, but congenital spinal TB has been rarely reported. We present 2 cases of spinal TB (1 confirmed, 1 clinical diagnosis) in HIV-exposed infants with likely congenital transmission. Increased vigilance for congenital TB, including uncommon presentations, is needed, particularly in countries with high HIV and TB prevalence.
Chronic neuropathic pain reduces opioid receptor availability with associated anhedonia in rat
Authors: Thompson Scott J. , Pitcher Mark H. , Stone Laura S. , Tarum Farid , Niu Gang , Chen Xiaoyuan , Kiesewetter Dale O. , Schweinhardt Petra , Bushnell M. Catherine
Published: May 2018

The opioid system plays a critical role in both the experience and management of pain. Although acute activation of the opioid system can lead to pain relief, the effects of chronic pain on the opioid system remain opaque. Cross-sectional positron emission tomography (PET) studies show reduced availability of brain opioid receptors in patients with chronic pain but are unable to (1) determine whether these changes are due to the chronic pain itself or due to preexisting or medication-induced differences in the endogenous opioid system, and (2) identify the neurobiological substrate of reduced opioid receptor availability. We investigated these possibilities using a well-controlled longitudinal study design in rat. Using [18F]-FDPN-PET in either sham rats (n = 17) or spared nerve injury rats (n = 17), we confirmed reduced opioid receptor availability in the insula, caudate–putamen, and motor cortex of nerve injured rats 3 months after surgery, indicating that painful neuropathy altered the endogenous opioid system. Immunohistochemistry showed reduced expression of the mu-opioid receptor, MOR1, in the caudate–putamen and insula. Neither the opioid peptide enkephalin nor the neuronal marker NeuN differed between groups. In nerve-injured animals, sucrose preference, a measure of anhedonia/depression-like behavior, positively correlated with PET opioid receptor availability and MOR1-immunoreactivity in the caudate–putamen. These findings provide new evidence that the altered supraspinal opioid receptor availability observed in human patients with chronic pain may be a direct result of chronic pain. Moreover, reduced opioid receptor availability seems to reflect decreased receptor expression, which may contribute to pain-induced depression.