bluuebunny/crossref_metadata_2025 huggingface dataset:
Receipt of Caregiving and Fall Risk in US Community-dwelling Older Adults
Authors: Hoffman Geoffrey J. , Hays Ron D. , Wallace Steven P. , Shapiro Martin F. , Yakusheva Olga , Ettner Susan L.
Published: November 2016

Background:

Falls and fall-related injuries (FRI) are common and costly occurrences among older adults living in the community, with increased risk for those with physical and cognitive limitations. Caregivers provide support for older adults with physical functioning limitations, which are associated with fall risk.

Design:

Using the 2004–2012 waves of the Health and Retirement Study, we examined whether receipt of low (0–13 weekly hours) and high levels (≥14 weekly hours) of informal care or any formal care is associated with lower risk of falls and FRIs among community-dwelling older adults. We additionally tested whether serious physical functioning (≥3 activities of daily living) or cognitive limitations moderated this relationship.

Results:

Caregiving receipt categories were jointly significant in predicting noninjurious falls (P=0.03) but not FRIs (P=0.30). High levels of informal care category (P=0.001) and formal care (P<0.001) had stronger associations with reduced fall risk relative to low levels of informal care. Among individuals with ≥3 activities of daily living, fall risks were reduced by 21% for those receiving high levels of informal care; additionally, FRIs were reduced by 42% and 58% for those receiving high levels of informal care and any formal care. High levels of informal care receipt were also associated with a 54% FRI risk reduction among the cognitively impaired.

Conclusions:

Fall risk reductions among older adults occurred predominantly among those with significant physical and cognitive limitations. Accordingly, policy efforts involving fall prevention should target populations with increased physical functioning and cognitive limitations. They should also reduce financial barriers to informal and formal caregiving.
Implications of molecular genetic diversity in myelodysplastic syndromes
Authors: Bejar Rafael
Published: November 2016

Purpose of review

Myelodysplastic syndromes (MDS) have remarkably diverse somatic mutation patterns that can be challenging to interpret clinically. Yet, genetic information is increasingly available to physicians. This review will examine several implications of genetic diversity in MDS.

Recent findings

Somatic mutations can serve as clinically relevant biomarkers in MDS. Molecular subtypes may exist that share clinical features including risk of progression to acute myeloid leukemia, response to treatment, and overall survival. Several mutated genes are known to have prognostic value that is independent of common risk stratification tools. Mutations of several genes identify low-blast percentage patients with greater than predicted disease risk while only SF3B1 mutations predict lower disease risk than expected. Mutations of TP53 are associated with adverse features, yet demonstrate inferior outcomes than predicted by these risk factors. SF3B1 and TP53 mutations may identify clinically relevant subtypes of MDS and allow for better refinement of risk within these groups. Using somatic mutations to diagnose MDS is more challenging because they can occur in healthy individuals. Yet, patients with unexplained cytopenias have a high rate of clonal hematopoiesis that may be an important risk factor to identify clinically.

Patterns of somatic mutations are diverse in MDS, but can inform the prediction of prognosis and aid in its diagnosis.
Immune Hemolytic Anemia (Paroxysmal Cold Hemoglobinuria) Preceding Burkitt Lymphoma in a 12-Year-Old Child
Authors: Ghanim Majd T. , Berman Brian
Published: November 2016

Autoimmune hemolytic anemia (AIHA) in childhood, including paroxysmal cold hemoglobinuria, is an uncommon, potentially life-threatening disorder. AIHA is a recognized complication of several varieties of lymphoproliferative disorders, including high-grade B-cell lymphoma, but it has not been associated with Burkitt lymphoma in people without an underlying immunodeficiency. When AIHA occurs in association with lymphoproliferative disorders, it may precede or accompany the diagnosis of malignant disease or herald relapse. We report a novel case of a previously healthy child diagnosed with paroxysmal cold hemoglobinuria 14 months preceding the development of Burkitt lymphoma.
Incorporation of Leadership Rounds in CAUTI Prevention Efforts
Authors: Purvis Suzanne , Kennedy Gregory D. , Knobloch Mary Jo , Marver Amy , Marx John , Rees Susan , Safdar Nasia , Shirley Daniel
Published: November 2016

Leadership engagement is an important aspect of integrating best practices at the bedside. The catheter-associated urinary tract infection (CAUTI) prevention workgroup at our academic medical center implemented leadership rounding in partnership with clinical staff to increase participation in CAUTI prevention initiatives on inpatient units. There was an associated decrease in urinary catheter utilization and CAUTI rates. Implementation of leadership rounds should be considered as a part of comprehensive CAUTI prevention efforts in health care settings.
Spiritual Immersion
Authors: Galloway Sharon , Hand Mikel W.
Published: November 2016

This article describes the development, implementation, and evaluation of a simulation exercise designed to teach spiritual care to prelicensure nursing students. Participation in a spiritual care simulation resulted in improved knowledge and attitudes relating to spirituality and spiritual care. The results from this study demonstrate the value of using simulation and spiritual assessment to teach students how to recognize and respond therapeutically to spiritual needs.
Primary Cutaneous T-Cell Lymphomas Showing Gamma-Delta (γδ) Phenotype and Predominantly Epidermotropic Pattern are Clinicopathologically Distinct From Classic Primary Cutaneous γδ T-Cell Lymphomas
Authors: Merrill E. Dean , Agbay Rose , Miranda Roberto N. , Aung Phyu P. , Tetzlaff Michael T. , Young Ken H. , Curry Jonathan L. , Nagarajan Priyadharsini , Ivan Doina , Prieto Victor G. , Medeiros L. Jeffrey , Duvic Madeleine , Torres-Cabala Carlos A.
Published: November 2016

Primary cutaneous gamma-delta (γδ) T-cell lymphoma is a rare disease that typically involves the dermis and subcutis. Cases of primary cutaneous T-cell lymphomas showing γδ phenotype and predominantly epidermotropic pattern (EγδTCL) are not well defined. In this series, cases of primary cutaneous T-cell lymphomas showing γδ phenotype were reviewed and classified as predominantly epidermotropic (EγδTCL) when >75% of lymphoma cells resided in the epidermis or predominantly dermal and/or subcutaneous (DSγδTCL). Clinical, pathologic, and immunophenotypic features were compared in 27 biopsies from 13 patients of EγδTCL and 13 biopsies from 7 patients of DSγδTCL. The lymphoma cells were diffusely positive for CD3 and T-cell receptor (TCR)γ, mostly positive for granzyme B and TIA-1, variably positive for CD8, CD7, and CD30, and negative for CD4 and TCRβ. Two patients with EγδTCL had dissemination to lymph nodes and 1 to the lung; 1 patient with DSγδTCL had gastrointestinal involvement. The median survival of patients with EγδTCL was not reached, and with a median follow-up of 19.2 months, 3/13 died. In contrast, the median survival of patients with DSγδTCL was 10 months, and after a median follow-up of 15.6 months, 5/5 died (P<0.01). EγδTCL is a rare presentation of cutaneous T-cell lymphoma that can be distinguished from DSγδTCL based on the extent of epidermotropism and has a better prognosis and longer median survival than DSγδTCL. However, although EγδTCL resembles mycosis fungoides clinically and histologically, a subset of EγδTCL is more likely to behave more aggressively than typical mycosis fungoides.
Relationship Between HIV Infection, Antiretroviral Therapy, Inflammatory Markers, and Cerebrovascular Endothelial Function Among Adults in Urban China
Authors: Chow Felicia C. , Li Yanling , Hu Yinghuan , Chan Joy , Wang Huanling , Xu Weihai , Price Richard W. , Sorond Farzaneh A. , Li Taisheng
Published: November 2016

Background:

Cerebrovascular risk is increased in people living with HIV infection compared with age-matched uninfected individuals. Cerebrovascular endothelial dysfunction related to antiretroviral therapy (ART) and inflammation may contribute to higher stroke risk in HIV infection.

Methods:

We compared cerebral vasoreactivity—a measure of cerebrovascular endothelial function assessed by the breath-holding index (BHI) using transcranial Doppler ultrasound—between virologically suppressed Chinese HIV-infected individuals followed in an HIV clinic in Beijing, China, and uninfected controls. We constructed mixed-effects models to evaluate the association of HIV, ART, and inflammatory markers with cerebral vasoreactivity.

Results:

In an unadjusted model, HIV infection was associated with a trend toward lower cerebral vasoreactivity (BHI 1.08 versus 1.26, P = 0.079). In multivariable analyses, cholesterol modified the association between HIV infection and cerebral vasoreactivity (P = 0.015 for interaction). At a lower total cholesterol of 4.15 mmol/L, HIV was associated with lower cerebral vasoreactivity (BHI −0.28, P = 0.019), whereas at a cholesterol of 5.15 mmol/L, the reduction in cerebral vasoreactivity associated with HIV was no longer statistically significant (BHI −0.05, P = 0.64). Among HIV-infected individuals, use of lopinavir/ritonavir compared with efavirenz was associated with lower cerebral vasoreactivity (BHI −0.24, P = 0.040). We did not find a significant association between inflammatory markers and cerebral vasoreactivity.

Conclusions:

Cerebrovascular endothelial dysfunction associated with HIV infection may be most relevant for individuals with less traditional vascular risk, such as those with lower cholesterol. Further study of the impact of ART on cerebrovascular endothelial function is warranted to aid with ART selection in individuals at high cerebrovascular risk.
Switching l-dopa Therapy from Pulsatile to Pulse Administration Reduces Motor Complications in Parkinson's Disease
Authors: Mostile Giovanni , Nicoletti Alessandra , Dibilio Valeria , Luca Antonina , Raciti Loredana , Sciacca Giorgia , Cicero Calogero Edoardo , Vasta Rosario , Donzuso Giulia , Contrafatto Donatella , Zappia Mario
Published: November 2016

Objective

To evaluate the severity of wearing-off and dyskinesia in patients with complicated Parkinson disease (PD) after switchingl-dopa oral therapy from a “pulsatile” administration, consisting in intermittent multiple daily small doses of the drug, to a “pulse” administration, consisting in standard oral doses given at specific interdose intervals.

Methods

Thirty-four PD patients with motor complications were monitored twice with standardized waking day motor status evaluations using the Unified Parkinson Disease Rating Scale-Motor Examination (UPDRS-ME) and the Abnormal Involuntary Movement Scale (AIMS) after switchingl-dopa administration modality from “pulsatile” to “pulse.” To quantify predictable motor fluctuations, a Wearing Off Index was computed based on changes in treatment response magnitude.

Results

On the whole, after switching from “pulsatile” to “pulse” administration, there was a reduction in number ofl-dopa daily doses and an increase in the amount of the dosage of the single doses, AIMS maximum score decreased without increasing motor disability. More specifically, in predominant fluctuating patients, there was a significant reduction in UPDRS-ME average score as well as in Wearing Off Index. In predominant dyskinetic patients, there was a significant reduction in average and maximum AIMS scores with no changes in average and maximum UPDRS-ME scores.

Conclusions

Switchingl-dopa therapy from “pulsatile” to “pulse” modality may reduce the severity of wearing-off and dyskinesia in complicated PD.
Fingolimod Use for the Treatment of Multiple Sclerosis in a Clinical Practice Setting in Madrid
Authors: Galán Sánchez-Seco Victoria , Casanova-Peño Ignacio , Álvarez-Lafuente Roberto , Sánchez-Jiménez Mónica , García-Martínez Ángel , Domínguez-Mozo María Inmaculada , Arias-Leal Ana María , García-Montojo Marta , Arroyo-González Rafael
Published: November 2016

Objective

To assess the effectiveness and safety of fingolimod use in a Spanish clinical practice setting.

Methods

Retrospective study with multiple sclerosis patients who received at least 1 fingolimod dose between January 2004 and January 2015. Effectiveness and safety data were collected during the entire treatment of each patient. Analysis was performed for the total population and stratified according to prior treatment, sex, and age at treatment initiation.

Results

A total of 167 patients were included, 50.9% had prior immunomodulator use, 33.5% natalizumab use, and 15.6% were naive patients. The annual relapse rate (ARR) decreased for the total population at month 12 (62%) and month 24 (84%) (P < 0.0001, in both cases); for naive patients (P < 0.05) and patients with prior immunomodulator use (P < 0.0001); for patients with prior natalizumab use, the ARR kept low after treatment initiation (0.23). After 24 months, the proportion of relapse-free patients was 70% or greater and disability progression-free patients was 80% or greater. No significant differences were observed when the results were compared by prior treatment, sex, or age. Thirty-two patients (19.2%) reported adverse drug reactions and 9.6% discontinued: 4.8% due to adverse drug reactions and 4.8% for lack of effectiveness.

Conclusions

The results support fingolimod use due to clinical effectiveness, tolerability, and ease of administration.
A Comparison of Magnetic Resonance Imaging and Electroneuromyography for Denervated Muscle Diagnosis
Authors: Tepeli Betül , Karataş Metin , Coşkun Mehmet , Yemişçi Oya Ümit
Published: November 2016

Purpose:

The aim of this study was to evaluate the diagnostic value of magnetic resonance imaging (MRI) for muscle denervation due to focal lesions of the median nerve and to compare electrophysiological findings with MRI findings.

Methods:

Twenty-six patients with electrophysiological studies diagnosed for focal lesions of the median nerve were included in this study. Electrophysiological studies and MRI were conducted on 34 patients' hands. Patients' hands were divided into two groups based on edema findings revealed by the MRI: group 1 (edema-negative group; n = 24) and group 2 (edema-positive group; n = 10).

Results:

Positive correlations were found between the existence of edema in MRI and fibrillation, positive sharp waves, denervation, and the level of reduced recruitment pattern. In median nerve conduction studies, amplitude of compound muscle action potential and palm-to-wrist segment mixed-nerve action potentials were significantly lower, and also the third-digit wrist sensory nerve conduction velocity and mixed-nerve palm–wrist conduction velocity were significantly slower in group 2.

Conclusions:

For muscle denervation resulting from median nerve lesions, MRI findings correlated with electrophysiological findings; further study is required for the use of MRI.
Brief use of a specific gun in a violent game does not affect attitudes towards that gun
Authors: Hilgard Joseph , Engelhardt Christopher R. , Bartholow Bruce D.
Published: November 2016

Although much attention has been paid to the question of whether violent video games increase aggressive behaviour, little attention has been paid to how such games might encourage antecedents of gun violence. In this study, we examined how product placement, the attractive in-game presentation of certain real-world firearm brands, might encourage gun ownership, a necessary antecedent of gun violence. We sought to study how the virtual portrayal of a real-world firearm (the Bushmaster AR-15) could influence players' attitudes towards the AR-15 specifically and gun ownership in general. College undergraduates (
N
 = 176) played one of four modified video games in a 2 (gun: AR-15 or science-fiction control) × 2 (gun power: strong or weak) between-subjects design. Despite collecting many outcomes and examining many potential covariates and moderators, experimental assignment did little to influence outcomes of product evaluations or purchasing intentions with regard to the AR-15. Attitudes towards public policy and estimation of gun safety were also not influenced by experimental condition, although these might have been better tested by comparison against a no-violence control condition. By contrast, gender and political party had dramatic associations with all outcomes. We conclude that, if product placement shapes attitudes towards firearms, such effects will need to be studied with stronger manipulations or more sensitive measures.
A computational method for sharp interface advection
Authors: Roenby Johan , Bredmose Henrik , Jasak Hrvoje
Published: November 2016

We devise a numerical method for passive advection of a surface, such as the interface between two incompressible fluids, across a computational mesh. The method is called isoAdvector, and is developed for general meshes consisting of arbitrary polyhedral cells. The algorithm is based on the volume of fluid (VOF) idea of calculating the volume of one of the fluids transported across the mesh faces during a time step. The novelty of the isoAdvector concept consists of two parts. First, we exploit an isosurface concept for modelling the interface inside cells in a geometric surface reconstruction step. Second, from the reconstructed surface, we model the motion of the face–interface intersection line for a general polygonal face to obtain the time evolution
within
a time step of the submerged face area. Integrating this submerged area over the time step leads to an accurate estimate for the total volume of fluid transported across the face. The method was tested on simple two-dimensional and three-dimensional interface advection problems on both structured and unstructured meshes. The results are very satisfactory in terms of volume conservation, boundedness, surface sharpness and efficiency. The isoAdvector method was implemented as an OpenFOAM
®
extension and is published as open source.
The carbon and nitrogen ecophysiologies of two endemic tropical orchids mirrors those of their temperate relatives and the local environment
Authors: Hynson Nicole A.
Published: November 2016

Orchids are one of the most widely distributed plant families. However, current research on the ecophysiology of terrestrial orchids is biased towards temperate species. Thus, it is currently unknown whether tropical terrestrial orchids belong to similar trophic guilds as their temperate relatives. To examine the ecophysiologies of two tropical terrestrial orchids, I analysed the carbon and nitrogen stable isotope compositions and nitrogen concentrations of the Hawaiian endemics
Anoectochilus sandvicensis
and
Liparis hawaiensis
. I compared these values with those of surrounding vegetation and their temperate relatives. I found that
A. sandvicensis
was consistently enriched in the heavy isotope of nitrogen (
15
N) and had higher nitrogen (N) concentrations than surrounding vegetation, and these values were even higher than those of its temperate relatives. Carbon stable isotope composition among populations of
A. sandvicensis
varied by island. These results point to local environment and evolutionary history determining the ecophysiology of this species. Whereas
L.hawaiensis
was also enriched in
15
N and had on average higher N concentrations than surrounding vegetation, these values were not significantly different from temperate relatives, indicating that evolutionary history may be a stronger predictor of this orchid species' ecophysiology than environment. I suggest that both Hawaiian species are potentially partially mycoheterotrophic.
A facile, versatile approach to hydroxyl-anchored metal oxides with high Cr(VI) adsorption performance in water treatment
Authors: Ma Ji , Zuo-Jiang SiZhi , He Yunhao , Sun Qinglei , Wang Yunguo , Liu Wei , Sun Shuangshuang , Chen Kezheng
Published: November 2016

In this study, a facile and versatile urea-assisted approach was proposed to synthesize Chinese rose-like NiO, pinecone-like ZnO and sponge-like CoO adsorbents. The presence of urea during syntheses endowed these adsorbents with high concentration of surface hydroxyl groups, which was estimated as 1.83, 1.32 and 4.19 mmol [OH
−
] g
−1
for NiO, ZnO and CoO adsorbents, respectively. These surface hydroxyl groups would facilitate the adsorption of Cr(
vi
) species (e.g. HCrO
4
−
, Cr
2
O
7
2−
and CrO
4
2−
) from wastewater by exchanging with hydroxyl protons or hydroxide ions, and hence result in extremely high maximum adsorbed amounts of Cr(
vi
), being 2974, 14 256 and 408 mg g
−1
for NiO, ZnO and CoO adsorbents in the pH range of 5.02–5.66 at 298 K, respectively. More strikingly, the maximum adsorbed amounts of Cr(
vi
) would be greatly enhanced as the adsorbing temperature is increased, and even amount to 23 411 mg g
−1
for ZnO adsorbents at 323 K. Based on the kinetics and equilibrium studies of adsorptive removal of Cr(
vi
) from wastewater, our synthetic route will greatly improve the adsorptivity of the as-synthesized metal-oxide adsorbents, and hence it will shed new light on the development of high-performance adsorbents.
The potential of electricity transmission corridors in forested areas as bumblebee habitat
Authors: Hill Bruce , Bartomeus Ignasi
Published: November 2016

Declines in pollinator abundance and diversity are not only a conservation issue, but also a threat to crop pollination. Maintained infrastructure corridors, such as those containing electricity transmission lines, are potentially important wild pollinator habitat. However, there is a lack of evidence comparing the abundance and diversity of wild pollinators in transmission corridors with other important pollinator habitats. We compared the diversity of a key pollinator group, bumblebees (
Bombus
spp.), between transmission corridors and the surrounding semi-natural and managed habitat types at 10 sites across Sweden's Uppland region. Our results show that transmission corridors have no impact on bumblebee diversity in the surrounding area. However, transmission corridors and other maintained habitats such as roadsides have a level of bumblebee abundance and diversity comparable to semi-natural grasslands and host species that are important for conservation and ecosystem service provision. Under the current management regime, transmission corridors already provide valuable bumblebee habitat, but given that host plant density is the main determinant of bumblebee abundance, these areas could potentially be enhanced by establishing and maintaining key host plants. We show that in northern temperate regions the maintenance of transmission corridors has the potential to contribute to bumblebee conservation and the ecosystem services they provide.
Mutualists or parasites? Context-dependent influence of symbiotic fly larvae on carnivorous investment in the Albany pitcher plant
Authors: Lymbery Samuel J. , Didham Raphael K. , Hopper Stephen D. , Simmons Leigh W.
Published: November 2016

Carnivorous plants allocate more resources to carnivorous structures under nutrient-limited conditions, and relative investment can also be influenced by animals (infauna) that live in association with these plants and feed on their prey. We investigated these effects within a population of the pitcher plant
Cephalotus follicularis
containing varying densities of larvae of the fly
Badisis ambulans
. For plants with a relatively high proportion of adult pitchers, increasing larval density was associated with lower relative leaf allocation to new pitcher buds. For plants with relatively few adult pitchers, however, there was greater relative leaf allocation to pitcher buds with increasing larval density. In a field experiment, there was no significant effect of experimental larval presence or absence on the change in carbon-to-nitrogen (C/N) ratio of plants. Although the direction of the correlation between
B. ambulans
larvae and relative investment in carnivorous and non-carnivorous structures depends on the relative number of mature structures, whether the larvae enhance or reduce nutrient stress under different conditions remains unclear. The change in C/N was, however, less variable for pitchers that contained larvae, suggesting a stabilizing effect. Eighteen of 52 experimental pitchers were damaged by an unknown species, causing the pitcher fluid to drain. These pitchers were significantly more likely to survive if they contained larvae. These results suggest that the relationship between infauna and host varies with the initial resource status and environmental context of the host plant.
The quantum CP-violating kaon system reproduced in the electronic laboratory
Authors: Caruso M. , Fanchiotti H. , García Canal C. A. , Mayosky M. , Veiga A.
Published: November 2016

The equivalence between the Schrödinger dynamics of a quantum system with a finite number of basis states and a classical dynamics is realized in terms of electric networks. The isomorphism that connects in a univocal way both dynamical systems was applied to the case of neutral mesons, kaons in particular, and the class of electric networks univocally related to the quantum system was analysed. Moreover, under
CPT
invariance, the relevant
ϵ
parameter that measures
CP
violation in the kaon system is reinterpreted in terms of network parameters. All these results were explicitly shown by means of both a numerical simulation of the implied networks and by constructing the corresponding circuits.
Electrodynamics of spoof plasmons in periodically corrugated waveguides
Authors: Erementchouk Mikhail , Joy Soumitra Roy , Mazumder Pinaki
Published: November 2016

States of the electromagnetic field confined near a periodically corrugated surface of a perfect conductor, spoof surface plasmon polaritons (SSPP), are approached systematically based on the developed adaptation of the mode matching technique to the transfer matrix formalism. Within this approach, in the approximation of narrow grooves, systems with arbitrary transversal structure can be investigated straightforwardly, thus lifting the restrictions of the effective medium description and usual implementations of mode matching. A compact expression for the SSPP coupling parameter accounting for the effect of higher Bloch modes is found. The results of the general analysis are applied for studying the effect of dielectric environment on SSPP spectra. It is shown that the effective SSPP plasma frequency is unaffected by the dielectric constant of the medium outside of the grooves and the main effect of sufficiently wide dielectric slabs covering the corrugated surface is described by simple rescaling of the maximal value of the Bloch wavenumber and the coupling parameter. Additionally, in the case of a thin dielectric layer, it is shown that SSPP are sensitive to variation of the thickness of the layer on the sub-wavelength scale.
On the continuum limit for a semidiscrete Hirota equation
Authors: Pickering Andrew , Zhao Hai-qiong , Zhu Zuo-nong
Published: November 2016

In this paper, we propose a new semidiscrete Hirota equation which yields the Hirota equation in the continuum limit. We focus on the topic of how the discrete space step
δ
affects the simulation for the soliton solution to the Hirota equation. The Darboux transformation and explicit solution for the semidiscrete Hirota equation are constructed. We show that the continuum limit for the semidiscrete Hirota equation, including the Lax pair, the Darboux transformation and the explicit solution, yields the corresponding results for the Hirota equation as

δ
→
0

.
Directional selection effects on patterns of phenotypic (co)variation in wild populations
Authors: Assis A. P. A. , Patton J. L. , Hubbe A. , Marroig G.
Published: November 2016

Phenotypic (co)variation is a prerequisite for evolutionary change, and understanding how (co)variation evolves is of crucial importance to the biological sciences. Theoretical models predict that under directional selection, phenotypic (co)variation should evolve in step with the underlying adaptive landscape, increasing the degree of correlation among co-selected traits as well as the amount of genetic variance in the direction of selection. Whether either of these outcomes occurs in natural populations is an open question and thus an important gap in evolutionary theory. Here, we documented changes in the phenotypic (co)variation structure in two separate natural populations in each of two chipmunk species (
Tamias alpinus
and
T. speciosus
) undergoing directional selection. In populations where selection was strongest (those of
T. alpinus
), we observed changes, at least for one population, in phenotypic (co)variation that matched theoretical expectations, namely an increase of both phenotypic integration and (co)variance in the direction of selection and a re-alignment of the major axis of variation with the selection gradient.
Experimental evidence that honeybees depress wild insect densities in a flowering crop
Authors: Lindström Sandra A. M. , Herbertsson Lina , Rundlöf Maj , Bommarco Riccardo , Smith Henrik G.
Published: November 2016

While addition of managed honeybees (
Apis mellifera
) improves pollination of many entomophilous crops, it is unknown if it simultaneously suppresses the densities of wild insects through competition. To investigate this, we added 624 honeybee hives to 23 fields of oilseed rape (
Brassica napus
L.) over 2 years and made sure that the areas around 21 other fields were free from honeybee hives. We demonstrate that honeybee addition depresses the densities of wild insects (bumblebees, solitary bees, hoverflies, marchflies, other flies, and other flying and flower-visiting insects) even in a massive flower resource such as oilseed rape. The effect was independent of the complexity of the surrounding landscape, but increased with the size of the crop field, which suggests that the effect was caused by spatial displacement of wild insects. Our results have potential implications both for the pollination of crops (if displacement of wild pollinators offsets benefits achieved by adding honeybees) and for conservation of wild insects (if displacement results in negative fitness consequences).
Natural bounds on herbivorous coral reef fishes
Authors: Heenan Adel , Hoey Andrew S. , Williams Gareth J. , Williams Ivor D.
Published: November 2016

Humans are an increasingly dominant driver of Earth's biological communities, but differentiating human impacts from natural drivers of ecosystem state is crucial. Herbivorous fish play a key role in maintaining coral dominance on coral reefs, and are widely affected by human activities, principally fishing. We assess the relative importance of human and biophysical (habitat and oceanographic) drivers on the biomass of five herbivorous functional groups among 33 islands in the central and western Pacific Ocean. Human impacts were clear for some, but not all, herbivore groups. Biomass of browsers, large excavators, and of all herbivores combined declined rapidly with increasing human population density, whereas grazers, scrapers, and detritivores displayed no relationship. Sea-surface temperature had significant but opposing effects on the biomass of detritivores (positive) and browsers (negative). Similarly, the biomass of scrapers, grazers, and detritivores correlated with habitat structural complexity; however, relationships were group specific. Finally, the biomass of browsers and large excavators was related to island geomorphology, both peaking on low-lying islands and atolls. The substantial variability in herbivore populations explained by natural biophysical drivers highlights the need for locally appropriate management targets on coral reefs.
Neuroendocrine correlates of sex-role reversal in barred buttonquails
Authors: Voigt Cornelia
Published: November 2016

Sex differences in brain structure and behaviour are well documented among vertebrates. An excellent model exploring the neural mechanisms of sex differences in behaviour is represented by sex-role-reversed species. In the majority of bird species, males compete over access to mates and resources more strongly than do females. It is thought that the responsible brain regions are therefore more developed in males than in females. Because these behaviours and brain regions are activated by androgens, males usually have increased testosterone levels during breeding. Therefore, in species with sex-role reversal, certain areas of the female brain should be more developed or steroid hormone profiles should be sexually reversed. Here, I studied circulating hormone levels and gene expression of steroid hormone receptors and aromatase in a captive population of barred buttonquails (Turnix suscitator). While females performed courtship and agonistic behaviours, there was no evidence for sexually reversed hormone profiles. However, I found female-biased sex differences in gene expression of androgen receptors in several hypothalamic and limbic brain regions that were already in place at hatching. Such sex differences are not known from non-sex-role-reversed species. These data suggest that increased neural sensitivity to androgens could be involved in the mechanisms mediating sex-role-reversed behaviours.
Rates of change in climatic niches in plant and animal populations are much slower than projected climate change
Authors: Jezkova Tereza , Wiens John J.
Published: November 2016

Climate change may soon threaten much of global biodiversity. A critical question is: can species undergo niche shifts of sufficient speed and magnitude to persist within their current geographic ranges? Here, we analyse niche shifts among populations within 56 plant and animal species using time-calibrated trees from phylogeographic studies. Across 266 phylogeographic groups analysed, rates of niche change were much slower than rates of projected climate change (mean difference > 200 000-fold for temperature variables). Furthermore, the absolute niche divergence among populations was typically lower than the magnitude of projected climate change over the next approximately 55 years for relevant variables, suggesting the amount of change needed to persist may often be too great, even if these niche shifts were instantaneous. Rates were broadly similar between plants and animals, but especially rapid in some arthropods, birds and mammals. Rates for temperature variables were lower at lower latitudes, further suggesting that tropical species may be especially vulnerable to climate change.
Towards a theory of individual differences in statistical learning
Authors: Siegelman Noam , Bogaerts Louisa , Christiansen Morten H. , Frost Ram
Published: November 2016

In recent years, statistical learning (SL) research has seen a growing interest in tracking individual performance in SL tasks, mainly as a predictor of linguistic abilities. We review studies from this line of research and outline three presuppositions underlying the experimental approach they employ: (i) that SL is a unified theoretical construct; (ii) that current SL tasks are interchangeable, and equally valid for assessing SL ability; and (iii) that performance in the standard forced-choice test in the task is a good proxy of SL ability. We argue that these three critical presuppositions are subject to a number of theoretical and empirical issues. First, SL shows patterns of modality- and informational-specificity, suggesting that SL cannot be treated as a unified construct. Second, different SL tasks may tap into separate sub-components of SL that are not necessarily interchangeable. Third, the commonly used forced-choice tests in most SL tasks are subject to inherent limitations and confounds. As a first step, we offer a methodological approach that explicitly spells out a potential set of different SL dimensions, allowing for better transparency in choosing a specific SL task as a predictor of a given linguistic outcome. We then offer possible methodological solutions for better tracking and measuring SL ability. Taken together, these discussions provide a novel theoretical and methodological approach for assessing individual differences in SL, with clear testable predictions.

This article is part of the themed issue ‘New frontiers for statistical learning in the cognitive sciences’.
Predicting causal variants affecting expression using whole genome sequence and RNA-seq from multiple human tissues
Authors: Anand Brown Andrew , Viñuela Ana , Delaneau Olivier , Spector Tim , Small Kerrin , Dermitzakis Emmanouil T
Published: November 2016

Genetic association mapping produces statistical links between phenotypes and genomic regions, but identifying the causal variants themselves remains difficult. Complete knowledge of all genetic variants, as provided by whole genome sequence (WGS), will help, but is currently financially prohibitive for well powered GWAS studies. To explore the advantages of WGS in a well powered setting, we performed eQTL mapping using WGS and RNA-seq, and showed that the lead eQTL variants called using WGS are more likely to be causal. We derived properties of the causal variant from simulation studies, and used these to propose a method for implicating likely causal SNPs. This method predicts that 25% - 70% of the causal variants lie in open chromatin regions, depending on tissue and experiment. Finally, we identify a set of high confidence causal variants and show that they are more enriched in GWAS associations than other eQTL. Of these, we find 65 associations with GWAS traits and show examples where the gene implicated by expression has been functionally validated as relevant for complex traits.
Visual crowding is a combination of an increase of positional uncertainty, source confusion, and featural averaging
Authors: Harrison William J , Bex Peter J
Published: November 2016

Although we perceive a richly detailed visual world, our ability to identify 1 individual objects is severely limited in clutter, particularly in peripheral vision. Models of such crowding have generally been driven by the phenomenological misidentifications of crowded targets: using stimuli that do not easily combine to form a unique symbol (e.g. letters or objects), observers typically confuse the source of objects and report either the target or a distractor, but when continuous features are used (e.g. orientated gratings or line positions) observers report a feature somewhere between the target and distractor. To reconcile these accounts, we develop a hybrid method of adjustment that allows detailed analysis of these multiple error categories. Observers reported the orientation of a target, under several distractor conditions, by adjusting an identical foveal target. We apply new modelling to quantify whether perceptual reports show evidence of positional uncertainty, source confusion, and featural averaging on a trial-by-trial basis. Our results show that observers make a large proportion of source-confusion errors. However, our study also reveals the distribution of perceptual reports that underlie performance in this crowding task more generally: aggregate errors cannot be neatly labelled because they are heterogeneous and their structure depends on target-distractor distance.
An RNA binding polymer specifies nematode sperm fate
Authors: Aoki Scott Takeo , Porter Douglas F , Prasad Aman , Wickens Marvin , Bingman Craig A , Kimble Judith
Published: November 2016

Metazoan germ cells develop as sperm or oocytes, depending on chromosomal sex, extrinsic signaling from somatic tissue and intrinsic factors within the germ cells. Gamete fate regulatory networks have been analyzed in nematodes, flies and mammals, but only in C. elegans have terminal intrinsic regulators been identified, which include a Tob/BTG protein family member, FOG-3. Canonical Tob/BTG proteins function as monomeric adaptor proteins that link RNA binding proteins to deadenylases. To ask if FOG-3 functions similarly, we first determined its crystal structure. FOG-3 harbors a classical Tob/BTG fold, but unlike other Tob/BTG proteins, FOG-3 dimerizes and these FOG-3 dimers assemble into polymers. The importance of FOG-3 polymers to sperm fate specification was confirmed in vivo using CRISPR/Cas9 gene editing to create mutations designed to disrupt the polymer interface. The FOG-3 surface potential is highly basic, suggesting binding to nucleic acid. We find that FOG-3 binds RNA directly with a strong preference for 3'UTRs of oogenic mRNAs. Our results reveal a divergent but striking molecular assembly for proteins with a Tob/BTG fold, make key advances in understanding the mechanism of sperm fate specification and highlight the potential for undiscovered protein polymers in biology.
Distinct sources of deterministic and stochastic components of action timing decisions in rodent frontal cortex
Authors: Murakami Masayoshi , Shteingart Hanan , Loewenstein Yonatan , Mainen Zachary F.
Published: November 2016

The selection and timing of actions are subject to determinate influences such as sensory cues and internal state as well as to effectively stochastic variability. Although stochastic choice mechanisms are assumed by many theoretical models, their origin and mechanisms remain poorly understood. Here we investigated this issue by studying how neural circuits in the frontal cortex determine action timing in rats performing a waiting task. Electrophysiological recordings from two regions necessary for this behavior, medial prefrontal cortex (mPFC) and secondary motor cortex (M2), revealed an unexpected functional dissociation. Both areas encoded deterministic biases in action timing, but only M2 neurons reflected stochastic trial-by-trial fluctuations. This differential coding was reflected in distinct timescales of neural dynamics in the two frontal cortical areas. These results suggest a two-stage model in which stochastic components of action timing decisions are injected by circuits downstream of those carrying deterministic bias signals.
Ancient hybridization and strong adaptation to viruses across African vervet monkey populations
Authors: Svardal Hannes , Jasinska Anna J , Apetrei Cristian , Coppola Giovanni , Huang Yu , Schmitt Christopher A , Jacquelin Beatrice , Müller-Trutwin Michaela , Weinstock George , Paul Grobler J , Wilson Richard K , Turner Trudy R , Warren Wesley C , Freimer Nelson B , Nordborg Magnus
Published: November 2016

Vervet monkeys (genusChlorocebus, also known as African green monkeys), are highly abundant in savannahs and riverine forests throughout sub-Saharan Africa. They are amongst the most widely distributed nonhuman primates, show considerable phenotypic diversity, and have long been an important biomedical model for a variety of human diseases1and in vaccine research2–4. They are particularly interesting for HIV/AIDS research as they are the most abundant natural hosts of simian immunodeficiency virus (SIV), a close relative of HIV. Here we present the first genome-wide survey of polymorphism in vervets, using sequencing data from 163 individuals sampled from across Africa and the Caribbean islands where vervets were introduced during the colonial era. We find high diversity, within and between taxa, and clear evidence that taxonomic divergence was reticulate rather than following a simple branching pattern. A scan for diversifying selection across vervet taxa yields gene enrichments much stronger than in similar studies on humans5. In particular, we report strong and highly polygenic selection signals affecting viral processes — in line with recent evidence that proposes a driving role for viruses in protein evolution in mammals6. Furthermore, selection scores are highly elevated in genes whose human orthologs interact with HIV, and in genes that show a response to experimental SIV infection in vervet monkeys but not in rhesus macaques, suggesting that part of the signal reflects taxon-specific adaptation to SIV. Intriguingly, rather than affecting genes with antiviral and inflammatory-related functions7, selection in vervets appears to have primarily targeted genes involved in the transcriptional regulation of viruses, and in particular those that are harmful only under immunodeficiency, suggesting adaptation to living with SIV rather than defense against infection.
Estimating Drivers of Cell State Transitions Using Gene Regulatory Network Models
Authors: Schlauch Daniel , Glass Kimberly , Hersh Craig P. , Silverman Edwin K. , Quackenbush John
Published: November 2016

Specific cellular states are often associated with distinct gene expression patterns. These states are plastic, changing during development, or in the transition from health to disease. One relatively simple extension of this concept is to recognize that we can classify different cell-types by their active gene regulatory networks and that, consequently, transitions between cellular states can be modeled by changes in these underlying regulatory networks. Here we describeMONSTER,MOdelingNetworkStateTransitions fromExpression andRegulatory data, a regression-based method for inferring transcription factor drivers of cell state conditions at the gene regulatory network level. As a demonstration, we apply MONSTER to four different studies of chronic obstructive pulmonary disease to identify transcription factors that alter the network structure as the cell state progresses toward the disease-state. Our results demonstrate that MONSTER can find strong regulatory signals that persist across studies and tissues of the same disease and that are not detectable using conventional analysis methods based on differential expression. An R package implementing MONSTER is available at github.com/QuackenbushLab/MONSTER.
Age and sex modulate the variability of neural responses to naturalistic videos
Authors: Petroni Agustin , Cohen Samantha , Ai Lei , Langer Nicolas , Henin Simon , Vanderwal Tamara , Milham Michael P. , Parra Lucas C.
Published: November 2016

Neural development is generally marked by an increase in the efficiency and diversity of neural processes. In a large sample (N = 114) of children and adults with ages ranging from 5 −44 years, we investigated the neural responses to naturalistic video stimuli. Videos from both real-life classroom settings and Hollywood feature films were used to probe different aspects of attention and engagement. For all stimuli, older ages were marked by more variable neural responses. Variability was assessed by the inter-subject correlation of evoked electroencephalographic (EEG) responses. Young males also had more variable responses than young females. These results were replicated in an independent cohort (N = 303). When interpreted in the context of neural maturation, we conclude that neural function becomes more variable with maturity, at least in during the passive viewing of real-world stimuli.

Significance Statement

Naturalistic videos were used to measure how a large sample of children and adults process environmentally meaningful stimuli. As age increased, neural responses were more variable, and females responded more variably than males - a difference that disappeared with age. These results are consistent with developmental theories positing that neural variability increases with maturation, and that neural maturation typically occurs earlier in females. This is the first study to investigate neural variability under naturalistic conditions in a developmental sample.