bluuebunny/crossref_metadata_2025 huggingface dataset:
Metabolic programming a lean phenotype by deregulation of RNA polymerase III
Authors: Willis Ian M. , Moir Robyn D. , Hernandez Nouria
Published: November 2018

Significance

As a repressor of transcription by RNA polymerase (Pol) III, Maf1 is thought to play an important role in the energetic economy of cells by controlling the synthesis of highly abundant tRNAs and 5S rRNA. Accordingly,Maf1knockout mice are lean, resist weight gain on normal and high fat diets, and up-regulate catabolic processes to meet their increased demand for cellular energy. The origin of this energy demand is proposed to reside in a futile cycle of RNA synthesis and turnover that is enhanced by constitutive Pol III transcription. We present metabolomic evidence supporting this mechanism. We find that central metabolic pathways are reprogrammed in the liver ofMaf1knockout mice to direct substrates toward energy generation and nucleotide synthesis.
African-American Rhetorical Education and Epistolary Relations at the Holley School (1868–1917)
Authors: VanHaitsma Pamela
Published: November 2018

This study establishes the Holley School as an important site of African-American rhetorical education in the post–Civil War United States. Abolitionist Caroline F. Putnam was a white Northerner who, like countless other freedmen’s teachers, moved south after the war to teach formerly enslaved African Americans. Putnam’s educational work was remarkable, however, in that she taught rhetoric in service of racial justice and continued this work for almost fifty years. I argue that she was able to sustain the Holley School through epistolary relations cultivated to persuade others to join in educating freedmen as well as support the school through donations.
Restricting short‐wavelength light in the evening to improve sleep in recreational athletes – A pilot study
Authors: Knufinke Melanie , Fittkau‐Koch Lennart , Møst Els I. S. , Kompier Michiel A. J. , Nieuwenhuys Arne
Published: November 2018

Sleep is crucial for recovery and skill acquisition in athletes. Paradoxically, athletes often encounter difficulties initiating and maintaining sleep, while having sufficient sleep opportunity. Blue (short‐wavelength) light as emitted by electronic screens is considered a potential sleep thief, as it suppresses habitual melatonin secretion. The current study sought to investigate whether blocking short‐wavelength light in the evening can improve sleep onset latency and potentially other sleep parameters among recreational athletes. The study had a within‐subject crossover design. Fifteen recreational athletes, aged between 18 and 32 years (12 females, 3 males), were randomly assigned to start the intervention period with either the light restriction condition (LR; amber‐lens glasses), or the no‐light restriction condition (nLR; transparent glasses). Sleep hygiene practices, actigraphy and diary‐based sleep estimates were monitored during four consecutive nights within each condition. Sleep hygiene practices did not significantly differ between conditions. Results indicate that blocking short‐wavelength light in the evening, as compared to habitual light exposure, significantly shortened subjective sleep onset latency (Δ = 7 min), improved sleep quality (Δ = 0.6; scale 1–10), and increased alertness the following morning. Actigraphy‐based sleep estimates showed no significant differences between conditions. Blocking short‐wavelength light in the evening by means of amber‐lens glasses is a cost‐efficient and promising means to improve subjective sleep estimates among recreational athletes in their habitual home environment. The relatively small effects of the current study may be strengthened by additionally increasing morning‐ and daytime light exposure and, potentially, by reducing the alerting effects of media use before bedtime.
Nitrogen enrichment alters carbon fluxes in a New England salt marsh
Authors: Geoghegan Emily K. , Caplan Joshua S. , Leech Francine N. , Weber Paige E. , Bauer Caitlin E. , Mozdzer Thomas J.
Published: November 2018

Introduction:
Nitrogen enrichment of coastal salt marshes can induce feedbacks that alter ecosystem-level processes including primary production and carbon sequestration. Despite the rising interest in coastal blue carbon, the effects of chronic nutrient enrichment on blue carbon processes have rarely been measured in the context of experimental fertilization. Here, we examined the ecosystem-level effects of nitrate (NO
3
−
) enrichment on the greenhouse gas dynamics of a
Spartina alterniflora
-dominated salt marsh. We measured CO
2
and CH
4
fluxes using static chambers through two growing seasons in a salt marsh that was nitrogen-enriched for 13 years and compared fluxes to those from a reference marsh.

Outcomes
: We found that nitrogen enrichment increased gross primary productivity (GPP) by 7.7% and increased ecosystem respiration (R
eco
) by 20.8%. However, nitrogen enrichment had no discernible effect on net ecosystem exchange (NEE). Taken together, these results suggest that nitrogen-induced stimulation of R
eco
could transform this salt marsh from a carbon sink into a source of carbon to the atmosphere.

Conclusion:
Our results complement prior findings of nitrogen enrichment weakening soil structure and organic matter stability in tidal salt marshes, suggesting that increased nutrient inputs have the potential to alter the carbon storage function of these ecosystems through enhanced microbial respiration of previously sequestered carbon.
The conduit system exports locally secreted IgM from lymph nodes
Authors: Thierry Guilhem R. , Kuka Mirela , De Giovanni Marco , Mondor Isabelle , Brouilly Nicolas , Iannacone Matteo , Bajénoff Marc
Published: November 2018

Immunoglobulin M (IgM) is the first type of antibody produced during acute infections and thus provides an early line of specific defense against pathogens. Being produced in secondary lymphoid organs, IgM must rapidly be exported to the blood circulation. However, it is currently unknown how such large pentameric molecules are released from lymph nodes (LNs). Here, we show that upon immunization, IgM transiently gains access to the luminal side of the conduit system, a reticular infrastructure enabling fast delivery of tissue-derived soluble substances to the LN parenchyma. Using microinjections of purified IgM, we demonstrate that conduit-associated IgM is delivered by neither the afferent lymph nor the blood, but is locally conveyed by conduits. Exploiting in vivo models, we further demonstrate that conduit-associated IgM is locally and transiently produced by activated, antigen-specific B cells migrating in the T cell zone. Thus, our study reveals that the conduit system is coopted by B cells to rapidly export secreted IgM out of LNs.
Integral comparison of Monsky–Washnitzer and overconvergent de Rham–Witt cohomology
Authors: Ertl Veronika , Sprang Johannes
Published: November 2018

The goal of this short note is to extend a result by Christopher Davis and David Zureick-Brown on the comparison between integral Monsky–Washnitzer cohomology and overconvergent de Rham–Witt cohomology for a smooth variety over a perfect field of positive characteristic

p
p

to all cohomological degrees independent of the dimension of the base or the prime number

p
p

.

Résumé. Le but de ce travail est de prolonger un résultat de Christopher Davis et David Zureick-Brown concernant la comparaison entre la cohomologie de Monsky–Washnitzer entière et la cohomologie de de Rham–Witt surconvergente d’une variété lisse sur un corps parfait de charactéristique positive

p
p

à tous les degrés cohomologiques indépendent de la dimension de base et du nombre premier

p
p

.
Differential symmetric signature in high dimension
Authors: Brenner Holger , Caminata Alessio
Published: November 2018

We study the differential symmetric signature, an invariant of rings of finite type over a field, introduced in a previous work by the authors in an attempt to find a characteristic-free analogue of the F-signature. We compute the differential symmetric signature for invariant rings

k
[

x
1

,
…
,

x
n

]
G

k[x_1,\dots ,x_n]^G

, where

G
G

is a finite small subgroup of GL

(
n
,
k
)

(n,k)

, and for hypersurface rings

k
[

x
1

,
…
,

x
n

]

/

(
f
)

k[x_1,\dots ,x_n]/(f)

of dimension

≥
3

\geq 3

with an isolated singularity. In the first case, we obtain the value

1

/

|

G

|

1/|G|

, which coincides with the F-signature and generalizes a previous result of the authors for the two-dimensional case. In the second case, following an argument by Bruns, we obtain the value

0
0

, providing an example of a ring where differential symmetric signature and F-signature are different.
Normal numbers with digit dependencies
Authors: Aistleitner Christoph , Becher Verónica , Carton Olivier
Published: November 2018

We give metric theorems for the property of Borel normality for real numbers under the assumption of digit dependencies in their expansion in a given integer base. We quantify precisely how much digit dependence can be allowed such that almost all real numbers are normal. Our theorem states that almost all real numbers are normal when at least slightly more than

log
⁡
log
⁡
n

\log \log n

consecutive digits with indices starting at position

n
n

are independent. As the main application, we consider the Toeplitz set

T
P

T_P

, which is the set of all sequences

a
1

a
2

…

a_1a_2 \ldots

of symbols from

{
0
,
…
,
b
−
1
}

\{0, \ldots , b-1\}

such that

a
n

a_n

is equal to

a

p
n

a_{pn}

for every

p
p

in

P
P

and

n
=
1
,
2
,
…

n=1,2,\ldots

. Here 

b
b

is an integer base and 

P
P

is a finite set of prime numbers. We show that almost every real number whose base

b
b

expansion is in 

T
P

T_P

is normal to base 

b
b

. In the case when

P
P

is the singleton set

{
2
}

\{2\}

we prove that more is true: almost every real number whose base

b
b

expansion is in

T
P

T_P

is normal to all integer bases. We also consider the Toeplitz transform which maps the set of all sequences to the set

T
P

T_P

, and we characterize the normal sequences whose Toeplitz transform is normal as well.
A variational time discretization for compressible Euler equations
Authors: Cavalletti Fabio , Sedjro Marc , Westdickenberg Michael
Published: November 2018

We introduce a variational time discretization for the multidimensional gas dynamics equations, in the spirit of minimizing movements for curves of maximal slope. Each time step requires the minimization of a functional measuring the acceleration of fluid elements, over the cone of monotone transport maps. We prove convergence to measure-valued solutions for the pressureless gas dynamics and the compressible Euler equations. For one space dimension, we obtain sticky particle solutions for the pressureless case.
Metformin suppresses the esophageal carcinogenesis in rats treated with NMBzA through inhibiting AMPK/mTOR signaling pathway
Authors: Fan Hongjun , Yu Xiying , Zou Zhigeng , Zheng Wei , Deng Xin , Guo Liping , Jiang Wei , Zhan Qimin , Lu Shih-Hsin
Published: November 2018

Metformin is a widely used antidiabetic drug for the management of type 2 diabetes mellitus. Recently, epidemiological studies demonstrate that metformin has anticancer effects on esophageal squamous cell carcinoma (ESCC) and other cancers. However, the effects and potential mechanisms of metformin on ESCC remain elusive. In this study, we used N-nitroso-N-methylbenzylamine (NMBzA), a special carcinogen for esophagi, to develop a rat ESCC model, in which the carcinogenesis progression of ESCC in rat was induced and promoted. We investigated the effects of metformin on carcinogenesis of ESCC in this model. Our results revealed that metformin significantly decreased the incidence and precancerous lesions of ESCC and inhibited proliferation and promoted apoptosis of esophageal epithelial cells in rat treated with NMBzA. Moreover, metformin also increased apoptosis and inhibited migration, colony formation and tumor sphere formation of human ESCC cells in vitro. Immunohistochemistry and western blotting showed that without interfering the metabolism of NMBzA, metformin inhibited the inflammation of esophagi via reducing the expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and interleukin-6 (IL-6). Treatment of metformin led to activation of AMP-activated protein kinase (AMPK) and attenuated signaling of the downstream molecules such as p-mTOR, p-p70S6K and cyclin D1 expression both in vivo and in vitro. Taken together, our study demonstrated that metformin suppressed the carcinogenesis of ESCC through inhibiting AMPK/mammalian target of the rapamycin (mTOR) signaling pathway, resulting in its chemopreventive effects on the carcinogenesis of ESCC.
ErbB4 acts as a suppressor in colitis and its associated carcinoma by negatively regulating cholesterol metabolism
Authors: Ni Hengli , Chen Lin , Song Liming , Sun Lina , Cui Hongxia , Zhou Qun , Hu Caihong , Jiao Weijuan , Shen Tong , Gao Tianming , Liu Yao , Li Jianming
Published: November 2018

Previously we reported that ErbB4 played a protective role in chronic liver injury and hepatocellular carcinoma. Herein, we examined the role of ErbB4 in the development of colitis-associated cancer (CAC) in ErbB4 knockout mice models, in vitro cell lines and clinical samples. We found that ErbB4 deficiency may lead to more severe inflammation, slower recovery and the development of CAC. Further, loss of ErbB4 could activate Kras by upregulating rate-limiting enzymes in cholesterol metabolism pathway through interacting with the transcription factor Srebf1. In clinic samples, ErbB4 is downregulated in colonic tissues from patients with Crohn’s disease. And data from The Cancer Genome Atlas also showed significant negative correlation between ErbB4 and several cholesterol metabolic enzymes. In summary, our study uncovers ErbB4 as a protector in the development of CAC, for its loss could activate Kras by upregulating cholesterol metabolism.
The impact of a theory-based web-intervention on the intention to use prescription drugs for non-medical purposes among college students: a randomized controlled trial
Authors: Arabyat Rasha M , Borrego Matthew , Hamidovic Ajna , Sleath Betsy , Raisch Dennis W
Published: November 2018

The non-medical use of prescription drugs (NMUPD) among college students is escalating at an alarming rate. A limited number of studies have utilized a theoretical framework to influence this behavior. To utilize the reasoned-action approach theory to design and evaluate a web-based intervention to influence students’ attitudes, perceived norms (PNs), perceived behavioral control (PBC) and intentions toward NMUPD. Using a two-group post-test only controlled trial, students were randomized to view either a general health website or a web-based intervention focused on NMUPD. The intervention was presented in multiple sections to address each component of the reasoned-action approach. Subsequently, respondents completed a web-survey. Independent t-tests were used to compare responses between the two groups. Of 391 respondents, 112 (28.9%) students indicated previous NMUPD. The intervention group had significantly (P = 0.04) more negative attitudes toward NMUPD. No significant differences were found in PNs (P = 0.11), PBC (P = 0.68) or intentions to NMUPD (P = 0.97). The intervention was successful in changing attitudes toward NMUPD. Targeting the intervention toward college students regardless of previous experiences of NMUPD might have led to insufficiency of the intervention to influence intentions. Additional research is needed to improve the intervention dissemination and utilization.
Shedding light on the link between early life sun exposure and risk of multiple sclerosis: results from the EnvIMS Study
Authors: Magalhaes Sandra , Pugliatti Maura , Riise Trond , Myhr Kjell-Morten , Ciampi Antonio , Bjornevik Kjetil , Wolfson Christina
Published: November 2018

Background

Lower levels of sun exposure in childhood have been suggested to be associated with increased risk of multiple sclerosis (MS). In this paper we extend previous work, using two novel analytical strategies.

Methods

Data collected in the Environmental risk factors In MS (EnvIMS) study, a case-control study with MS cases and population-based controls from Canada, Italy and Norway, were used. Participants reported on sun exposure behaviours for 5-year age intervals from birth; we focused on the first three age intervals (≤15 years). We compared two life course epidemiology conceptual models, the critical period and the accumulation model. We also used latent class analysis to estimate MS risk for different latent sun exposure behaviour groups.

Results

The analyses included 2251 cases and 4028 controls. The accumulation model was found to be the best model, which demonstrated a nearly 50% increased risk of MS comparing lowest reported summer sun exposure with highest [risk ratio (RR) = 1.47 (1.24, 1.74)]. The latent sun exposure behaviour group, characterized by low sun exposure during summer and winter and high sun protection use, had the highest risk of MS; a 76% increased risk as compared with the group with high sun exposure and low sun protection use [RR = 1.76 (1.27, 2.46)].

Conclusions

Our analyses provide novel insights into the link between sun exposure and MS. We demonstrate that more time indoors during childhood and early adolescence is linked with MS risk, and that sun protection behaviours in those who spend most time indoors may play a key role in increasing risk.
Translating Solitons of the Mean Curvature Flow Asymptotic to Hyperplanes in ℝn+1
Authors: Gama Eddygledson S , Martín Francisco
Published: November 2018

A translating soliton is a hypersurface $M$ in ${\mathbb{R}}^{n+1}$ such that the family $M_t= M- t \,\mathbf e_{n+1}$ is a mean curvature flow, that is, such that normal component of the velocity at each point is equal to the mean curvature at that point $\mathbf{H}=\mathbf e_{n+1}^{\perp }.$ In this paper we obtain a characterization of hyperplanes that are parallel to the velocity and the family of tilted grim reaper cylinders as the only translating solitons in $\mathbb{R}^{n+1}$ that are $C^1$-asymptotic to two half-hyperplanes outside a non-vertical cylinder. This result was proven for translators in $\mathbb{R}^3$ by the 2nd author, Perez-Garcia, Savas-Halilaj, and Smoczyk under the additional hypotheses that the genus of the surface was locally bounded and the cylinder was perpendicular to the translating velocity.
People-powered data collaboratives: fueling data science with the health-related experiences of individuals
Authors: Evans Barbara J , Krumholz Harlan M
Published: November 2018

The creation of people-driven data collaboratives, with governance structures that enable participants to have a meaningful voice in issues surrounding the use of their own data, is a novel strategy to harness our growing capacity to develop and maintain immense data assets from the real health experiences of individuals.
Finding ‘anonymous’ in the digital archives: The problem of Arden of Faversham
Authors: Taylor Gary
Published: November 2018

This investigation re-examines debates about the authorship of the play Arden of Faversham, first published (anonymously) in 1592, and sometimes attributed to Shakespeare, Kyd, or Marlowe. More generally, it seeks to explain why modern data-driven attribution methods, which have created consensus about the authorship of The Revenger's Tragedy and other seventeenth-century plays, have failed to produce consistent results for plays written for the London commercial theaters in the years up to 1594. It proposes that attribution problems in that period can be better understood if plays are tested against authorial canons that include non-dramatic as well as dramatic works, using algorithms based on the evidence of n-grams and collocations, which seem not to be genre-dependent. It tests a sample passage from Scene 10 of Arden against the digital canons of fifteen writers known or suspected to have been writing for the commercial theater in the period 1585–92, using primarily EEBO-TCP. All tests identify the author as the poet, translator, and playwright Thomas Watson (1555–92). These data do not establish Watson's authorship of the entire play but open several new lines of enquiry for Arden and other anonymous and collaborative early plays.
Stochastic entropy production in the quite Sun magnetic fields
Authors: Gorobets Andriy Y , Berdyugina Svetlana V
Published: November 2018

The second law of thermodynamics imposes an increase of macroscopic entropy with time in an isolated system. Microscopically, however, the entropy production can be negative for a single, microscopic realization of a thermodynamic process. The so-called fluctuation theorems provide exact relations between the stochastic entropy consumption and generation. Here, we analyse pixel-to-pixel fluctuations in time of small-scale magnetic fields (SSMF) in the quiet Sun observed with the SDO/HMI instrument. We demonstrate that entropy generated by SSMF obeys the fluctuation theorems. In particular, the SSMF entropy consumption probability is exactly exponentially smaller than the SSMF entropy generation probability. This may have fundamental implications for the magnetic energy budget of the Sun.
Extreme AGN variability: evidence of magnetically elevated accretion?
Authors: Dexter Jason , Begelman Mitchell C
Published: November 2018

Rapid, large amplitude variability at optical to X-ray wavelengths is now seen in an increasing number of Seyfert galaxies and luminous quasars. The variations imply a global change in accretion power, but are too rapid to be communicated by inflow through a standard thin accretion disc. Such discs are long known to have difficulty explaining the observed optical/UV emission from active galactic nuclei. Here we show that alternative models developed to explain these observations have larger scale heights and shorter inflow times. Accretion discs supported by magnetic pressure in particular are geometrically thick at all luminosities, with inflow times as short as the observed few year time-scales in extreme variability events to date. Future time-resolved, multiwavelength observations can distinguish between inflow through a geometrically thick disc as proposed here, and alternative scenarios of extreme reprocessing of a central source or instability-driven limit cycles.
Rewarding Effects of Nicotine in Adolescent and Adult Male and Female Rats as Measured Using Intracranial Self-stimulation
Authors: Xue Song , Behnood-Rod Azin , Wilson Ryann , Wilks Isaac , Tan Sijie , Bruijnzeel Adriaan W
Published: November 2018

Introduction

Tobacco is highly addictive, and after the development of dependence, it is difficult to quit smoking. Therefore, it is important to understand the factors that play a role in the initiation of smoking. The rewarding effects of nicotine play a role in the initiation of smoking and the goal of the present study was to determine the rewarding effects of nicotine in adolescent and adult male and female rats.

Methods

Male and female Wistar rats were prepared with intracranial self-stimulation (ICSS) electrodes between postnatal day (P) 23 and 33. They were then trained on the ICSS procedure and the effect of nicotine (0, 0.03, 0.1, 0.3 mg/kg) on the reward thresholds and response latencies was investigated during adolescence (P40–59) or adulthood (>P75).

Results

Nicotine lowered the brain reward thresholds of the adult and adolescent male and female rats. The nicotine-induced decrease in the reward thresholds was the same in the adult male and adult female rats. However, nicotine induced a greater decrease in the reward thresholds of the adolescent female rats than the adolescent male rats. Nicotine decreased the response latencies of all groups and there was no effect of age or sex.

Conclusions

Nicotine enhances reward function and psychomotor performance in adolescent and adult male and female rats. Adolescent female rats are more sensitive to the acute rewarding effects of nicotine than adolescent male rats. Therefore, the rewarding effects of nicotine might play a greater role in the initiation of smoking in adolescent females than in adolescent males.

Implications

The great majority of people start smoking during adolescence. The present studies suggest that during this period female rats are more sensitive to the acute rewarding effects of low and intermediate doses of nicotine than male rats. The rewarding properties of nicotine play a role in the initiation of smoking and establishing habitual smoking. Therefore, the present findings might explain why adolescent females are at a higher risk for becoming nicotine dependent than adolescent males.
An unbiased spectral line survey observation toward the low-mass star-forming region L1527
Authors: Yoshida Kento , Sakai Nami , Nishimura Yuri , Tokudome Tomoya , Watanabe Yoshimasa , Sakai Takeshi , Takano Shuro , Yamamoto Satoshi
Published: November 2018

An unbiased spectral line survey toward a solar-type Class 0/I protostar, IRAS 04368+2557, in L1527 has been carried out in the 3 mm band with the Nobeyama 45 m telescope. L1527 is known as a warm carbon-chain chemistry (WCCC) source, which harbors abundant unsaturated organic species such as CnH (n = 3, 4, 5, …) in a warm and dense region near the protostar. The observation covers the frequency range from 80 to 116 GHz. A supplementary observation has also been conducted in the 70 GHz band to observe fundamental transitions of deuterated species. In total, 69 molecular species are identified, among which 27 species are carbon-chain species and their isomers, including their minor isotopologues. This spectral line survey provides us with a good template of the chemical composition of the WCCC source.
Cardiopulmonary Responses During Clinical and Laboratory Gait Assessments in People With Chronic Stroke
Authors: Woodward Jane L , Connolly Mark , Hennessy Patrick W , Holleran Carey L , Mahtani Gordhan B , Brazg Gabrielle , Fahey Meghan , Maganti Kameswari , Hornby T George
Published: November 2018

Background

The 6-Minute Walk Test (6MWT) is a common clinical assessment used to evaluate locomotor function in patients after stroke. Previous work suggests the 6MWT can estimate peak metabolic capacity (VO2peak) without cardiorespiratory assessments during graded exercise tests (GXTs), which may assist with exercise prescription. However, selected research also indicated increased heart rates (HRs) during 6MWTs beyond levels considered safe without GXTs.

Objective

The goal of this study was to examine cardiorespiratory responses during 6MWTs and GXTs in individuals with chronic stroke and their associations with demographic or clinical characteristics.

Design

The study used a cross-sectional observational design.

Methods

Cardiorespiratory responses were assessed during 6MWTs at self-selected velocity (SSV) and fastest velocity (FV), and during GXTs. Secondary assessments included the lower extremity Fugl-Meyer Assessment, Functional Gait Assessment, gait speeds, and daily stepping activity. Correlation and regression analyses were used to evaluate associations between locomotor performance, cardiorespiratory responses, and clinical and demographic characteristics.

Results

Average HRs during 6MWT-FV were 72% to 76% of the age-predicted maximum (HRmax), with 20% of participants exceeding 85% predicted HRmax. When normalized to HRs during GXTs, HRs during 6MWT-FV were 86% to 88% of observed HRmax. Primary predictors of increased HRs during 6MWTs were resting HR, body mass index, and daily stepping. Distance during 6MWT-FV was a significant predictor of VO2peak in combination with other variables. Electrocardiographic abnormalities were observed in >80% of participants at rest and 31% demonstrated distinct abnormalities during GXTs, which were not related to 6MWT or GXT performance.

Limitations

In addition to sample size, a primary limitation involved the ability to accurately predict or measure HRmax in patients with motor dysfunction after stroke.

Conclusions

Cardiac responses were higher than anticipated during 6MWTs and often exceeded recommended HR thresholds. Clinicians should closely monitor cardiorespiratory responses during 6MWTs.
The Effects of Losing a Business Group Affiliation
Authors: Larrain Borja , Sertsios Giorgo , Urzúa I Francisco
Published: November 2018

We propose a novel identification strategy for estimating the effects of business group affiliation. We study two-firm business groups, some of which split up during the sample period, leaving some firms as stand-alone firms. We instrument for stand-alone status using shocks to the industry of the other group firm. We find that firms that become stand-alone reduce leverage and investment. Consistent with collateral cross-pledging, the effects are more pronounced when the other firm had high tangibility. Consistent with capital misallocation in groups, the reduction in leverage is stronger in firms that had low (high) profitability (leverage) relative to industry peers.

Received July 3, 2017; editorial decision April 7, 2018 by Editor Wei Jiang. Authors have furnished an Internet Appendix, which is available on the Oxford University Press Web site next to the link to the final published paper online.
Inside autoimmune liver disease
Authors: Pullen Richard L. , Francis-Johnson Patricia
Published: November 2018

An overactive immune system can target any body tissue and cause damage. In AILD, the liver and bile ducts are under attack.
A systematic approach to shoulder and knee MRI for the sports medicine physician
Authors: Rothfeld Alex , Jacobs Matt B. , Papp Derek F. , Fritz Jan
Published: November 2018

Sports medicine physicians should develop a systematic approach to review MRIs. Collaboration between orthopaedic sports medicine clinicians and radiologists is critical to obtain the most accurate diagnosis. The ability to correlate clinical information can improve the accuracy of a diagnostic study. We present a straightforward method to evaluate both knee and shoulder MRIs. Although the authors recognize that other approaches exist, we believe that a systematic and collaborative approach will benefit sports medicine physicians throughout the entirety of their careers.
Mothers' Perspectives on Follow-up for Postpartum Depression Screening in Primary Care
Authors: Canty Hannah R. , Sauter Alicia , Zuckerman Katharine , Cobian Maritza , Grigsby Tamara
Published: November 2018

Objective:

To qualitatively assess mothers' perspectives on barriers to and facilitators of follow-up of at-risk postpartum depression (PPD) screening test results.

Methods:

We conducted semistructured qualitative telephone interviews with 17 women who scored in the moderate or high-risk range on the Edinburgh Postpartum Depression Scale. Interviews explored personal experience with depressive symptoms, barriers and facilitators to receiving mental health care postpartum, and suggestions for primary care follow-up of at-risk screens. The team created a coding structure that was updated during review of transcripts. Findings were triangulated and external validity assessed via discussions with a mother who experienced PPD, a perinatal social worker, and a perinatal psychologist.

Results:

Personal health/attitude, family/friends, community, and health care system factors influenced mothers' follow-up of at-risk PPD screening test results. Health and personal attitude factors included anxiety, physical and emotional exhaustion, self-care and recognition of symptoms, and living up to personal and family expectations. Family/friend factors included material and emotional support and competing priorities. Community factors included child care affordability and availability, access to transportation, geographic access to resources, social networks, and community mental health stigma. Health care factors included pediatrician taking the mother's symptoms seriously, adequate time with the pediatrician, mother and pediatrician focus on the child's health, and access to mental health referrals.

Conclusion:

Addressing barriers to follow-up after PPD screening may enable better service access for at-risk families.
Impacts of gestational age uncertainty in estimating associations between preterm birth and ambient air pollution
Authors: Nealy Benjamin E. , Warren Joshua L. , Strickland Matthew J. , Darrow Lyndsey A. , Chang Howard H.
Published: November 2018

Background:

Previous epidemiologic studies utilizing birth records have shown heterogeneous associations between air pollution exposure during pregnancy and the risk of preterm birth (PTB, gestational age <37 weeks). Uncertainty in gestational age at birth may contribute to this heterogeneity.

Methods:

We first examined disagreement between clinical and last menstrual period-based (LMP) determination of PTB from individual-level birth certificate data for the 20-county Atlanta metropolitan area during 2002 to 2006. We then estimated associations between five trimester-averaged pollutant exposures and PTB, defined using various methods based on the clinical or LMP gestational age. Finally, using a multiple imputation approach, we incorporated uncertainty in gestational age to quantify the impact of this variability on associations between pollutant exposures and PTB.

Results:

Odds ratios (OR) were most elevated when a more stringent definition of PTB was used. For example, defining PTB only when LMP and clinical diagnoses agree yielded an OR of 1.09 (95% confidence interval [CI] = 1.04, 1.14) per interquartile range increase in first trimester carbon monoxide exposure versus an OR of 1.04 (95% CI = 1.01, 1.08) when PTB was defined as either an LMP or clinical diagnosis. Accounting for outcome uncertainty resulted in wider CIs—between 7.4% and 43.8% wider than those assuming the PTB outcome is without error.

Conclusions:

Despite discrepancies in PTB derived using either the clinical or LMP gestational age estimates, our analyses demonstrated robust positive associations between PTB and ambient air pollution exposures even when gestational age uncertainty is present.
Testing the Efficacy of a Web-Based Parent-Adolescent Sexual Communication Intervention Among Puerto Ricans
Authors: Varas-Díaz Nelson , Betancourt-Díaz Elba , Lozano Alicia J. , Huang Liming , DiNapoli Lucia , Hanlon Alexandra , Villarruel Antonia M.
Published: November 2018

This randomized controlled trial tested the efficacy of a Web-based intervention to increase sexual communication between parents and adolescents. Parent/adolescent dyads (n = 660) were recruited from communities in the San Juan area and randomly assigned to the Cuídalos sexual communication or physical activity program. Parent assessments were obtained preintervention and at 3-, 6-, and 12-month follow-up. Parents in the experimental group reported significantly more sexual communication (ie, peer pressure, sexual prevention, protection, risk) over time than parents in the control group. Results support the efficacy of the Cuídalos Web-based format and provide insight into future Web-based sexual health interventions for this population.
Building and Sustaining Community Capacity to Address Childhood Obesity
Authors: Brock Donna-Jean P. , Estabrooks Paul A. , Hill Jennie L. , Barlow Morgan L. , Alexander Ramine C. , Price Bryan E. , Marshall Ruby , Zoellner Jamie M.
Published: November 2018

Guided by a community-based participatory research and systems-based approach, this 3-year mixed-methods case study describes the experiences and capacity development of a Community-Academic Advisory Board (CAB) formed to adapt, implement, and evaluate an evidence-based childhood obesity treatment program in a medically underserved region. The CAB included community, public health, and clinical (n = 9) and academic partners (n = 9). CAB members completed capacity evaluations at 4 points. Partners identified best practices that attributed to the successful execution and continued advancement of project goals. The methodological framework and findings can inform capacity development and sustainability of emergent community-academic collaborations.
Feasibility of Distinguishing Performance Among Provider Groups Using Patient-reported Outcome Measures in Older Adults With Multiple Chronic Conditions
Authors: Rose Adam J. , Bayliss Elizabeth , Baseman Lesley , Butcher Emily , Huang Wenjing , Edelen Maria O.
Published: November 2018

Objective:

To examine minimum sample sizes and follow-up times required for patient-reported outcome–based performance measures (PMs) to achieve acceptable reliability as PMs.

Participants:

We used 2 groups of patients age 65+ with at least 2 of 13 chronic conditions. The first was a sample of Medicare Advantage beneficiaries, who reported health-related quality of life (HRQoL) at baseline and 2 years. The second was a sample of primary care patients, who reported HRQoL at baseline and 6 months.

Measures:

Medicare Advantage beneficiaries completed the Veterans RAND 12-Item Short Form (VR-12), while the primary care sample completed the Patient-Reported Outcomes Measurement Information System 29-Item Profile Measure (PROMIS-29). We constructed binary candidate PMs indicating stable or improved physical or mental HRQoL at follow-up, and continuous PMs measuring mean change over time.

Results:

In the Medicare Advantage sample, with a sample size per entity profiled of 160, the most promising PM achieved a reliability of 0.32 as a PM. A sample size of 882 per entity would have been needed for this PM to achieve an acceptable reliability of 0.7. In the prospective sample, with a sample size of 27 per clinic, the most promising PM achieved a reliability of 0.16 as a PM. A sample size of 341 patients (at the clinic level) would have been needed for this PM to achieve a reliability of 0.7.

Conclusions:

Achieving acceptable reliability for these PMs and conditions would have required minimum sample sizes of 341 at the clinic level or 880 at the health plan level. These estimates can guide the design of future patient-reported outcome–based PMs.
Assessing Residual Bias in Estimating Influenza Vaccine Effectiveness
Authors: Butler Anne M. , Layton J. Bradley , Krueger Whitney S. , Kshirsagar Abhijit V. , McGrath Leah J.
Published: November 2018

Background:

Estimating influenza vaccine effectiveness using an unvaccinated comparison group may result in biased effect estimates.

Objectives:

To explore the reduction of confounding bias in an active comparison of high-dose versus standard-dose influenza vaccines, as compared with vaccinated versus unvaccinated comparisons.

Methods:

Using Medicare data from the United States end-stage renal disease program (2009–2013), we compared the risk of all-cause mortality among recipients of high-dose vaccine (HDV) versus standard-dose vaccine (SDV), HDV versus no vaccine, and SDV versus no vaccine. To quantify confounding bias, analyses were restricted to the preinfluenza season, when the protective effect of vaccination should not yet be observed. We estimated the standardized mortality ratio-weighted cumulative incidence functions using Kaplan-Meier methods and calculated risk ratios (RRs) and risk differences between groups.

Results:

Among 350,921 eligible patients contributing 825,642 unique patient preinfluenza seasons, 0.8% received HDV, 70.5% received SDV, and 28.7% remained unvaccinated. Comparisons with unvaccinated patients yielded spurious decreases in mortality risk during the preinfluenza period, for HDV versus none [RR, 0.60; 95% confidence interval (CI), 0.51–0.70)] and SDV versus none (RR, 0.72; 95% CI, 0.70–0.75). The effect estimate was attenuated in the HDV versus SDV comparison (RR, 0.89; 95% CI, 0.77–1.03). Estimates on the absolute scale followed a similar pattern.

Conclusions:

The HDV versus SDV comparison yielded less-biased estimates of the all-cause mortality before influenza season compared to those with nonuser comparison groups. Vaccine effectiveness and safety researchers should consider the active comparator design to reduce bias due to differences in underlying health status between vaccinated and unvaccinated individuals.
Mechanisms of leukemic transformation in congenital neutropenia
Authors: Link Daniel C.
Published: November 2018

Purpose of review

The development of a myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) in patients with congenital neutropenia is now the major cause of mortality. Treatment options are limited and there are no effective prevention strategies. This review focuses on mechanisms of leukemic transformation in severe congenital neutropenia (SCN) and Shwachman–Diamond syndrome (SDS), the two most common types of congenital neutropenia.

Recent findings

AML/MDS that develops in the setting of congenital neutropenia has distinct molecular features. Clonal hematopoiesis because ofTP53mutations is seen in nearly 50% of patients with SDS, but is not seen in patients with SCN. Accordingly, there is a very high frequency of TP53 mutations in AML/MDS arising in the setting of SDS but not SCN. The rate of mutation accumulation in hematopoietic stem cells (HSCs) from patients with congenital neutropenia is not increased.

Both HSC cell-intrinsic and noncell-intrinsic changes contribute to the development of clonal hematopoiesis in congenital neutropenia and likely accounts for the high rate of leukemic transformation. In SCN, the persistently high levels of granulocyte colony-stimulating factor drive expansion of HSCs carrying truncation mutations ofCSF3R. In SDS, impaired ribosome biogenesis induces p53-mediated growth inhibition and drives expansion of HSCs carryingTP53mutations.
Extended Use of Chimeric Medial Sural Artery Perforator Flap for 3-Dimensional Defect Reconstruction
Authors: Lee Che-Hsiung , Chang Nai-Jen Tommy , Hsiao Jo-Chun , Chu Yu-Ying , Lin Chih-Hung , Kao Huang-Kai , Lin Cheng-Hung
Published: November 2018

Background

The medial sural artery perforator (MSAP) flap has become increasingly popular because it is thin and pliable for small to moderate defect soft tissue reconstruction. Furthermore, chimeric MSAP flap, which includes a skin paddle and a separated piece of medial gastrocnemius muscle, allowed more freedom for flap insetting, especially in 3-dimensional defect reconstruction. Here we describe our experience regarding this clinical application.

Patients and Methods

From 2007 to 2016, 14 male patients (average age, 46.9 ± 14.4 years) who received either a free or pedicled chimeric MSAP flap were included. Of these 14 patients, 7 received this flap for reconstruction in the head and neck, 2 in the upper extremities, and 5 in the lower extremities. Demographic data were collected and analyzed, and a literature review was performed.

Results

Ten patients received free chimeric MSAP flap, and 4 received the pedicled type. Thirteen of the 14 flaps (92.6%) survived, and 1 failed 2 days later owing to venous insufficiency. Venous congestion-related partial loss occurred in another case.

Conclusions

The chimeric MSAP flap is a good alternative for deep space obliteration or reconstruction of adjacent but separate defects in both free and pedicled flap design. Donor site morbidity is limited. However, the perforator needs to be mobilized carefully to prevent postoperative venous compromise.
Health Literacy Burden Is Associated With Access to Liver Transplantation
Authors: Bababekov Yanik J. , Hung Ya-Ching , Rickert Charles G. , Njoku Faith C. , Cao Bonnie , Adler Joel T. , Brega Angela G. , Pomposelli James J. , Chang David C. , Yeh Heidi
Published: November 2018

Background.

Getting listed for liver transplantation is a complex process. Institutional health literacy may influence the ability of patients with limited educational attainment (EA) to list. As an easily accessible indicator of institutional health literacy, we measured the understandability of liver transplant center education websites and assessed whether there was any association with the percentage of low EA patients on their waitlists.

Methods.

Patients on the waitlist for liver transplantation 2007–2016 were identified in Scientific Registry of Transplant Recipients. Understandability of patient education websites was assessed using the Clear Communication Index (CCI). The Centers for Disease Control and Prevention has set itself a goal CCI of 90 as being easy to understand. Low EA was defined as less than a high school education. We adjusted for center case-mix, Donor Service Area characteristics, and EA of the general population.

Results.

Patients (84 774) were listed across 112 liver transplant centers. The median percent of waitlisted patients at each center with low EA was 11.0% (IQR, 6.6–16.8). CCI ranged from 53 to 88 and correlated with the proportion of low EA patients on the waitlist. However, CCI was not associated with the percentage of low EA in the general population. For every 1-point improvement in CCI, low EA patients increase by 0.2% (P < 0.05), translating to a 3.6% increase, or additional 3000 patients, if all centers improved their websites to CCI of 90.

Conclusions.

Educational websites that are easier to understand are associated with increased access to liver transplantation for patients with low EA. Lowering the health literacy burden by transplant centers may improve access to the liver transplant waitlist.
Negative biotic interactions drive predictions of distributions for species from a grassland community
Authors: Staniczenko Phillip P. A. , Suttle K. Blake , Pearson Richard G.
Published: November 2018

Understanding the factors that determine species' geographical distributions is important for addressing a wide range of biological questions, including where species will be able to maintain populations following environmental change. New methods for modelling species distributions include the effects of biotic interactions alongside more commonly used abiotic variables such as temperature and precipitation; however, it is not clear which types of interspecific relationship contribute to shaping species distributions and should therefore be prioritized in models. Even if some interactions are known to be influential at local spatial scales, there is no guarantee they will have similar impacts at macroecological scales. Here we apply a novel method based on information theory to determine which types of interspecific relationship drive species distributions. Our results show that negative biotic interactions such as competition have the greatest effect on model predictions for species from a California grassland community. This knowledge will help focus data collection and improve model predictions for identifying at-risk species. Furthermore, our methodological approach is applicable to any kind of species distribution model that can be specified with and without interspecific relationships.
Soil inorganic carbon in mangroves of tropical China: patterns and implications
Authors: Guan Wei , Xiong Yanmei , Liao Baowen
Published: November 2018

Soil inorganic carbon (IC) is neglected in most blue carbon studies despite the globally significant role of the calcium carbonate cycle in ocean C balance and climate change. We sampled soils to 1 m depth from seven mangrove reserves in Hainan Island, China. Only 45 out of 509 samples were rich in IC (greater than 10 mg cm
−3
). Most of the IC-rich samples were found at the outer part of Qinglan Bay, which is adjacent to the largest coral reef zone of Hainan Island. Soil IC concentration ranged from 0 to 66 g kg
−1
(or 0–67 mg cm
−3
), accounting for 0–92% of total C. IC concentration increased with soil depth where it was abundant. Soil pH was low (2.36–6.59) in IC-depleted soils, but increased to 5.67–7.99 in IC-rich soils. Soil total C stock and IC stock in mangroves of Hainan amounted to 0.76×10
6
and 0.12×10
6
Mg, respectively, with IC accounting for 16% of total C. Our study finds that carbonate concentrations can be high in mangrove soils but their spatial distribution indicates they are largely allochthonous in origin. Evidence of carbonate dissolution in mangroves suggests mangroves may increase total alkalinity to buffer acidification in seawater.