bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficacy of low concentrations of sodium hypochlorite and low‐powered Er,Cr:YSGG laser activated irrigation against an Enterococcus faecalis biofilm
Authors: Christo J. E. , Zilm P. S. , Sullivan T. , Cathro P. R.
Published: March 2015

Aim

To establish the antibacterial efficacy of low concentrations of sodium hypochlorite with and without Er,Cr:YSGG laser activation on Enterococcus faecalis biofilms in extracted teeth.

Methodology

The root canals of 96 decoronated single‐rooted extracted human teeth were prepared to a size 40, 0.06 taper 1 mm beyond the apex. They were mounted within a flow cell, which was sterilized before pumping a nutrient media through the root canals. The flow cell was inoculated with E. faecalis (ATCC 700802) and cultivated for 4 weeks. The root‐ends were sealed, and the roots were then subjected to one of six treatment groups: group 1: syringe irrigation (SI) with saline (control) using a 27 ‐gauge Monoject needle 1 mm from the apex for 2 min; group 2: as for group 1 but with 1% NaOCl; group 3: as for group 1 but with 4% NaOCl; group 4: 0.5% NaOCl irrigation for 15 s followed by laser‐activated irrigation (LAI) with four 15‐s cycles replenishing the irrigant between cycles; group 5: as for group 4 but with 1% NaOCl as the irrigant; group 6: as for group 4 but with 4% NaOCl as the irrigant. Following treatment, teeth were crushed and viable bacteria were quantitated by serial dilution and plating. The colony‐forming unit values were compared between groups using one‐way anova and Tukey‐adjusted post hoc tests. A two‐tailed P value of <0.05 was considered statistically significant.

Results

The mean number of cells recovered from the 1% NaOCl SI group was significantly higher than that from the 4% NaOCl LAI group (P = 0.02).

Conclusion

Within the limitations of this laboratory study, low‐powered (0.5 W) Er,Cr:YSGG laser activation did not improve the antibacterial effect of low concentrations of sodium hypochlorite.
Effects of storage and thawing conditions on coagulation testing
Authors: Gosselin R. C. , Honeychurch K. , Kang H. J. , Dwyre D. M.
Published: March 2015

Introduction

Current recommendations for coagulation testing storage and thawing are based on historical studies that were performed using unbuffered 3.8% sodium citrate. We sought to measure the effects of freezing and thawing conditions 3.2% buffered sodium citrate plasma samples that have been stored in vials with either snap or sealed screw tops, frozen in −70 °C freezer or dry ice and thawed either capped or uncapped.

Methods

Shed blood samples were pooled and then aliquoted into four snap top and four screw tops vials. Half the vials were stored in a −70 °C freezer, and half on dry ice for at least 16 h. Afterwards, half the frozen samples were thawed in 37 °C waterbath capped, and other half were thawed capped. After thawing cycles, samples were tested for PT, activated partial thromboplastin time (APTT), fibrinogen, D‐dimer, factor assays, von Willebrand factor activity, plasminogen, antithrombin, protein C and lupus anticoagulant.

Results

Prothrombin time, APTT, factor X, and lupus anticoagulant testing were affected by all vials, freezing and thawing conditions, whereas fibrinogen, D‐dimer, von Willebrand activity or protein C were not affected by any vial, freezing or storage condition.

Conclusions

Storage vials, freezing and thawing condition affect coagulation testing, although these differences may not be clinically significant.
Pointing to Nothing? Empty Places Prime Infants' Attention to Absent Objects
Authors: Liszkowski Ulf , Ramenzoni Verónica C.
Published: March 2015

People routinely point to empty space when referring to absent entities. These points to “nothing” are meaningful because they direct attention to places that stand in for specific entities. Typically, the meaning of places in terms of absent referents is established through preceding discourse and accompanying language. However, it is unknown whether nonlinguistic actions can establish locations as meaningful places, and whether infants have the capacity to represent a place as standing in for an object. In a novel eye‐tracking paradigm, 18‐month‐olds watched objects being placed in specific locations. Then, the objects disappeared and a point directed infants' attention to an emptied place. The point to the empty place primed infants in a subsequent scene (in which the objects appeared at novel locations) to look more to the object belonging to the indicated place than to a distracter referent. The place–object expectations were strong enough to interfere when reversing the place–object associations. Findings show that infants comprehend nonlinguistic reference to absent entities, which reveals an ontogenetic early, nonverbal understanding of places as representations of absent objects.
Non‐Standard “Contingent” Employment and Job Satisfaction: A Panel Data Analysis
Authors: Buddelmeyer Hielke , McVicar Duncan , Wooden Mark
Published: March 2015

Contingent forms of employment are usually associated with low‐quality jobs and, by inference, jobs that workers find relatively unsatisfying. This assumption is tested using data from a representative household panel survey covering a country (Australia) with a high incidence of nonstandard employment. Results from the estimation of ordered logit regression models reveal that among males, both casual employees and labor‐hire (agency) workers (but not fixed‐term contract workers) report noticeably lower levels of job satisfaction, though this association diminishes with job tenure. Negative effects for women are mainly restricted to labor‐hire workers.
Screening for High Blood Pressure in Adults During Ambulatory Nonprimary Care Visits: Opportunities to Improve Hypertension Recognition
Authors: Handler Joel , Mohan Yasmina , Kanter Michael H. , Reynolds Kristi , Li Xia , Nguyen Miki , Young Deborah R. , Koebnick Corinna
Published: March 2015

Visits with nonprimary care providers such as optometrists may be missed opportunities for the detection of high blood pressure (BP). For this study, normotensive adults with at least 12 months of health plan membership on January 1, 2009 (n=1,075,522) were followed‐up for high BP through March 14, 2011. Of 111,996 patients with a BP measurement ≥140/90 mm Hg, 82.7% were measured during primary care visits and 17.3% during nonprimary care visits. Individuals with a BP ≥140/90 mm Hg measured during nonprimary care visits were older and more likely to be male and non‐Hispanic white. The proportion of patients with follow‐up and false‐positives were comparable between primary and nonprimary care. The main nonprimary care specialty to identify a first BP ≥140/90 mm Hg was ophthalmology/optometry with 24.5% of all patients. Results suggest that expanding screening for hypertension to nonprimary care settings may improve the detection of hypertension.
Marginal Adaptation Evaluation of Biodentine and MTA Plus in “Open Sandwich” Class II Restorations
Authors: Aggarwal Vivek , Singla Mamta , Yadav Suman , Yadav Harish , Ragini
Published: March 2015

Purposes

This study aimed at evaluation of two different commercially available calcium silicate materials (Biodentine and mineral trioxide aggregate [MTA] Plus) used as dentin substitute.

Materials and Methods

Sixty Class II cavities were prepared in extracted mandibular third molars, with margins extending 1 mm below the cementum–enamel junction. The samples were divided into three groups on the basis of dentin substitute used: resin modified glass ionomer cement, Biodentine, and MTA Plus. Cavities were restored with composite resins in an “open sandwich” technique. The samples were subjected to alternate aging in phosphate buffered saline and cyclic loading. Marginal adaptation was evaluated in terms of “continuous margin” at the gingival margin, using a low vacuum scanning electron microscope. Statistical analysis was done with two‐way analysis of variance with Holm‐Sidak's correction for multiple comparisons.

Results

The glass ionomer group and Biodentine group presented an overall 83% and 91% of continuous margins, with no difference between them. MTA Plus showed least values of continuous margins. Granular deposits were seen over the surface of Biodentine and MTA Plus.

Conclusions

Biodentine and resin‐modified glass ionomer cement, when used as a dentin substitute under composite restorations in open sandwich technique, gave satisfactory marginal adaptation values.

Clinical Significance

Contemporary calcium silicate materials can be used as dentin substitute materials in “open sandwich” Class II restorations. This study evaluates the marginal adaptation of Biodentine, MTA Plus, and resin modified glass ionomer cement used as dentin substitutes and reports better adaptation obtained with Biodentine and glass ionomer cement.
Flood damage curves: new insights from the 2010 flood in Veneto, Italy
Authors: Scorzini A.R. , Frank E.
Published: March 2015

Flood damage modelling is becoming an essential component in flood risk management. However damage assessments are affected by large uncertainty, mainly related to the use of depth–damage functions. In some countries, where no site‐specific curves are available, a transfer of damage models developed from other areas is required, adding extra uncertainty in the modelling process. This paper discusses the transferability in space of damage curves from literature, with a focus on ‘function uncertainty’, pointing out, especially for mesoscale ones, the lack of detailed information in terms of flood and/or building characteristics that can allow to identify the conditions of applicability of the models. New site‐specific depth–damage functions are then developed for the residential sector, at meso‐ and microscale, based on damage data from the 2010 flood in Veneto, Italy. The application of the new curves reveals a better performance of the mesoscale model compared with the more detailed microscale one, probably due to the small extent of the inundated area.
How Circular is the Global Economy?: An Assessment of Material Flows, Waste Production, and Recycling in the European Union and the World in 2005
Authors: Haas Willi , Krausmann Fridolin , Wiedenhofer Dominik , Heinz Markus
Published: March 2015

It is increasingly recognized that the growing metabolism of society is approaching limitations both with respect to sources for resource inputs and sinks for waste and emission outflows. The circular economy (CE) is a simple, but convincing, strategy, which aims at reducing both input of virgin materials and output of wastes by closing economic and ecological loops of resource flows. This article applies a sociometabolic approach to assess the circularity of global material flows. All societal material flows globally and in the European Union (EU‐27) are traced from extraction to disposal and presented for main material groups for 2005. Our estimate shows that while globally roughly 4 gigatonnes per year (Gt/yr) of waste materials are recycled, this flow is of moderate size compared to 62 Gt/yr of processed materials and outputs of 41 Gt/yr. The low degree of circularity has two main reasons: First, 44% of processed materials are used to provide energy and are thus not available for recycling. Second, socioeconomic stocks are still growing at a high rate with net additions to stocks of 17 Gt/yr. Despite having considerably higher end‐of‐life recycling rates in the EU, the overall degree of circularity is low for similar reasons. Our results indicate that strategies targeting the output side (end of pipe) are limited given present proportions of flows, whereas a shift to renewable energy, a significant reduction of societal stock growth, and decisive eco‐design are required to advance toward a CE.
Controlled by Love: The Harmful Relational Consequences of Perceived Conditional Positive Regard
Authors: Kanat‐Maymon Yaniv , Roth Guy , Assor Avi , Raizer Abira
Published: March 2015

Research on conditional positive regard (CPR) has shown that this seemingly benign practice has maladaptive correlates when used by parents. However, there is no research on the correlates of this practice in romantic relationships or on the processes mediating its effects. Building on self‐determination theory (Deci & Ryan, ), three studies tested the hypothesis that perceived CPR impairs relationship quality, partly because it undermines the fulfillment of the basic psychological needs for autonomy and relatedness. Study 1 (N = 125) examined perceived CPR and relationship quality across four relationship targets: mother, father, romantic partner, and best friend. Study 2, involving romantic partners (N = 142), examined whether needs fulfillment mediated the association between perceived CPR and relationship quality. Study 3, involving romantic dyads (N = 85), also included partner reports on CPR. Across the three studies, CPR was linked with poor relationship quality between relationships, between people, and between dyadic partners. Moreover, results of Study 2 and Study 3 revealed that the inverse association between perceived CPR and relationship quality was mediated by dissatisfaction of autonomy but not relatedness. Despite its seemingly benign nature, CPR is detrimental to relationship quality, partly because it thwarts the basic need for autonomy.
Personality Trait Differences Between Young and Middle‐Aged Adults: Measurement Artifacts or Actual Trends?
Authors: Nye Christopher D. , Allemand Mathias , Gosling Samuel D. , Potter Jeff , Roberts Brent W.
Published: March 2015

A growing body of research demonstrates that older individuals tend to score differently on personality measures than younger adults. However, recent research using item response theory (IRT) has questioned these findings, suggesting that apparent age differences in personality traits merely reflect artifacts of the response process rather than true differences in the latent constructs. Conversely, other studies have found the opposite—age differences appear to be true differences rather than response artifacts. Given these contradictory findings, the goal of the present study was to examine the measurement equivalence of personality ratings drawn from large groups of young and middle‐aged adults (a) to examine whether age differences in personality traits could be completely explained by measurement nonequivalence and (b) to illustrate the comparability of IRT and confirmatory factor analysis approaches to testing equivalence in this context. Self‐ratings of personality traits were analyzed in two groups of Internet respondents aged 20 and 50 (n = 15,726 in each age group). Measurement nonequivalence across these groups was negligible. The effect sizes of the mean differences due to nonequivalence ranged from –.16 to .15. Results indicate that personality trait differences across age groups reflect actual differences rather than merely response artifacts.
Early Childhood Maltreatment and Pubertal Development: Replication in a Population‐Based Sample
Authors: Mendle Jane , Ryan Rebecca M. , McKone Kirsten M.
Published: March 2015

Early experiences are critically important for female reproductive development. Although a number of early childhood hardships predict earlier physical development in girls, research on specific populations suggests a distinct effect of childhood sexual abuse compared to other adversities. This study leverages the National Longitudinal Study of Adolescent Health (N = 6,273 girls) to test the generalizability of these findings, examining associations of early physical abuse, sexual abuse, and physical neglect with pubertal timing. Child sexual abuse predicted earlier menarche and development of secondary sexual characteristics, whereas other types of maltreatment did not. In addition to replicating results from smaller, more specialized samples, these findings reinforce the value of considering puberty within a broader “life span” continuum of birth to adolescence.
“Frozen in Time”: The Impact of Native American Media Representations on Identity and Self‐Understanding
Authors: Leavitt Peter A. , Covarrubias Rebecca , Perez Yvonne A. , Fryberg Stephanie A.
Published: March 2015

Mass media plays a substantial role in the way social groups understand themselves and are understood by others. Some social groups, like Native Americans, are rarely portrayed in mass media and, in the rare cases they appear, they are typically depicted in a stereotypical and historical fashion. The lack of contemporary representation of Native Americans in the media limits the ways in which Native Americans understand what is possible for themselves and how they see themselves fitting in to contemporary domains (e.g., education and employment) of social life. In this article, we contend that the invisibility of Native Americans in the media undermines self‐understanding by homogenizing Native American identity, creating narrow and limiting identity prototypes for Native Americans, and evoking deindividuation and self‐stereotyping among contemporary Native Americans.
Using Celebrity News Stories to Effectively Reduce Racial/Ethnic Prejudice
Authors: Ramasubramanian Srividya
Published: March 2015

This article argues that exposure to admirable media celebrities from racial/ethnic outgroups is an effective, proactive, and viable strategy for prejudice reduction and intergroup harmony. It uses mediated contact and exemplification theories to demonstrate that reading news stories about likable outgroup media personalities who serve as counter‐stereotypic exemplars can subtly modify racial attitudes, which are malleable and context‐sensitive. Specifically, results from a between‐participants experiment (N = 88) show that exposure to news stories about counter‐stereotypic African American media personalities as compared to stereotypical ones reduces stereotypical perceptions and symbolic racist beliefs of White Americans about African Americans. Furthermore, these favorable attitudes translate into an increased willingness to support affirmative action policies.
Racial and Ethnic Inclusion in the Digital Era: Shifting Discourses in Communications Public Policy
Authors: Castañeda Mari , Fuentes‐Bautista Martha , Baruch Felicitas
Published: March 2015

This article examines the representation of racial and ethnic minorities in contemporary U.S. broadband policy, an emerging area of communication policy that attempts to address merging media and telecommunications competition, diversity and inclusion issues for the digital age. A summary of three dominant themes in the literature regarding media diversity outlines the primary concerns of digital media policy. An interpretative policy analysis of the National Broadband Plan sheds lights on how regulators address diversity and access issues in the digital transition, particularly for communities of color. The analysis reveals that unlike prior exclusions of certain racial and ethnic groups in communications infrastructure, the unfolding broadband framework is attempting to be explicit about the inclusion of historically marginalized populations. We argue that the emerging media governance framework is both influenced by the problematic history of media diversity as well as a discursive and material shift that emphasizes market orientations.
Intervening in the Media's Influence on Stereotypes of Race and Ethnicity: The Role of Media Literacy Education
Authors: Scharrer Erica , Ramasubramanian Srividya
Published: March 2015

This article provides a review of the research record on the potential for media literacy education to intervene in the media's influence on racial and ethnic stereotypes, and explores the theoretical concepts that underlie these efforts. It situates media literacy theory and practice within particular emphases in the field and synthesizes qualitative and quantitative studies. Quantitative research on the effect of media literacy training and mediated counterstereotypes on reducing racial/ethnic prejudice is described. In addition, we report qualitative data from an ongoing study of early adolescents who took part in a media literacy curriculum on stereotypes. The research record reveals that although the topic is severely understudied, media literacy education holds great promise for its ability to shape media‐related knowledge, attitudes, and behaviors and encourage an active and critical stance toward media.
Eucalyptol suppresses matrix metalloproteinase-9 expression through an extracellular signal-regulated kinase-dependent nuclear factor-kappa B pathway to exert anti-inflammatory effects in an acute lung inflammation model
Authors: Kim Ka Young , Lee Hui Su , Seol Geun Hee
Published: March 2015

Objectives

The acute lung injury (ALI) model is characterised by a severe acute inflammatory response in the lungs that represents the pathogenesis of acute respiratory distress syndrome (ARDS). In this study, we sought to elucidate the anti-inflammatory mechanism of eucalyptol in relation to tissue remodelling in acute lung inflammation.

Methods

BALB/C mice were intraperitoneally injected with eucalyptol (100, 200 or 400 mg/kg) or dexamethasone (1 mg/kg) 1 h before intratracheal challenge with lipopolysaccharide (LPS; 1.5 mg/kg) and sacrificed after 4 h. The anti-inflammatory effects of eucalyptol were assessed by determining cell counts, measuring cytokine and nitric oxide production and performing Western blotting and histological analyses.

Key findings

Eucalyptol attenuated inflammation-associated increases in cell numbers, matrix metalloproteinase-9 (MMP-9) expression, production of cytokines (tumour necrosis factor-α and interleukin-6) and nitric oxide, and nuclear factor-kappa B (NF-κB) and phosphorylated extracellular signal-regulated kinase protein levels induced by LPS in bronchoalveolar lavage fluid from ALI mice. Furthermore, pretreatment with 400 mg/kg eucalyptol prevented LPS-induced histopathological changes. Collectively, these results indicate that eucalyptol acts through a mechanism involving decreased MMP-9 expression and an extracellular signal-regulated kinase-dependent NF-κB pathway to exert anti-inflammatory actions in acute lung inflammation.

Conclusions

Thus, eucalyptol may be a potentially important agent in the treatment of pulmonary inflammation.
Hepatitis B reactivation in HBsAg‐negative/HBcAb‐positive patients receiving rituximab for lymphoma: a meta‐analysis
Authors: Mozessohn L. , Chan K. K. W. , Feld J. J. , Hicks L. K.
Published: March 2015

Patients with chronic hepatitis B (HBsAg‐positive) are at risk of viral reactivation if rituximab is administered without antiviral treatment, a potentially fatal complication of treatment. Patients with so‐called ‘resolved hepatitis B virus infection’ (HBsAg‐negative/cAb‐positive) may also be at risk. We performed a systematic review of the English and Chinese language literature to estimate the risk of hepatitis B virus (HBV) reactivation in HBsAg‐negative/cAb‐positive patients receiving rituximab for lymphoma. A pooled risk estimate was calculated for HBV reactivation. The impact of HBsAb status and study design on reactivation rates was explored. Data from 578 patients in 15 studies were included. ‘Clinical HBV reactivation’, (ALT >3 × normal and either an increase in HBV DNA from baseline or HBsAg seroreversion), was estimated at 6.3% (I2 = 63%, P = 0.006). Significant heterogeneity was detected. Reactivation rates were higher in prospective vs retrospective studies (14.2% vs 3.8%; OR = 4.39, 95% CI 0.83–23.28). Exploratory analyses found no effect of HBsAb status on reactivation risk (OR = 0.083; P = 0.151). Our meta‐analysis confirms a measurable and potentially substantial risk of HBV reactivation in HBsAg‐negative/cAb‐positive patients exposed to rituximab. However, heterogeneity in the existing literature limits the generalizability of our findings. Large, prospective studies, with uniform definitions of HBV reactivation, are needed to clarify the risk of HBV reactivation in HBsAg‐negative/cAb‐positive patients.
Hydrogen and major element concentrations on 433 Eros: Evidence for an L‐ orLL‐chondrite‐like surface composition
Authors: Peplowski Patrick N. , Bazell David , Evans Larry G. , Goldsten John O. , Lawrence David J. , Nittler Larry R.
Published: March 2015

A reanalysis ofNEARX‐ray/gamma‐ray spectrometer (XGRS) data provides robust evidence that the elemental composition of the near‐Earth asteroid 433 Eros is consistent with the L andLLordinary chondrites. These results facilitated the use of the gamma‐ray measurements to produce the first in situ measurement of hydrogen concentrations on an asteroid. The measured value, ppm, is consistent with hydrogen concentrations measured in L andLLchondrite meteorite falls. Gamma‐ray derived abundances of hydrogen and potassium show no evidence for depletion of volatiles relative to ordinary chondrites, suggesting that the sulfur depletion observed in X‐ray data is a surficial effect, consistent with a space‐weathering origin. The newfound agreement between the X‐ray, gamma‐ray, and spectral data suggests that theNEARlanding site, a ponded regolith deposit, has an elemental composition that is indistinguishable from the mean surface. This observation argues against a pond formation process that segregates metals from silicates, and instead suggests that the differences observed in reflectance spectra between the ponds and bulk Eros are due to grain size differences resulting from granular sorting of ponded material.
The Corynebacterium glutamicum mycothiol peroxidase is a reactive oxygen species‐scavenging enzyme that shows promiscuity in thiol redox control
Authors: Pedre Brandán , Van Molle Inge , Villadangos Almudena F. , Wahni Khadija , Vertommen Didier , Turell Lucía , Erdogan Huriye , Mateos Luis M. , Messens Joris
Published: March 2015

Cysteine glutathione peroxidases (CysGPxs) control oxidative stress levels by reducing hydroperoxides at the expense of cysteine thiol (‐SH) oxidation, and the recovery of their peroxidatic activity is generally accomplished by thioredoxin (Trx). Corynebacterium glutamicum mycothiol peroxidase (Mpx) is a member of the CysGPx family. We discovered that its recycling is controlled by both the Trx and the mycothiol (MSH) pathway. After H2O2 reduction, a sulfenic acid (‐SOH) is formed on the peroxidatic cysteine (Cys36), which then reacts with the resolving cysteine (Cys79), forming an intramolecular disulfide (S‐S), which is reduced by Trx. Alternatively, the sulfenic acid reacts with MSH and forms a mixed disulfide. Mycoredoxin 1 (Mrx1) reduces the mixed disulfide, in which Mrx1 acts in combination with MSH and mycothiol disulfide reductase as a biological relevant monothiol reducing system. Remarkably, Trx can also take over the role of Mrx1 and reduce the Mpx‐MSH mixed disulfide using a dithiol mechanism. Furthermore, Mpx is important for cellular survival under H2O2 stress, and its gene expression is clearly induced upon H2O2 challenge. These findings add a new dimension to the redox control and the functioning of CysGPxs in general.
What plant hydraulics can tell us about responses to climate‐change droughts
Authors: Sperry John S. , Love David M.
Published: March 2015

Climate change exposes vegetation to unusual drought, causing declines in productivity and increased mortality. Drought responses are hard to anticipate because canopy transpiration and diffusive conductance (G) respond to drying soil and vapor pressure deficit (D) in complex ways. A growing database of hydraulic traits, combined with a parsimonious theory of tree water transport and its regulation, may improve predictions of at‐risk vegetation. The theory uses the physics of flow through soil and xylem to quantify how canopy water supply declines with drought and ceases by hydraulic failure. This transpiration ‘supply function’ is used to predict a water ‘loss function’ by assuming that stomatal regulation exploits transport capacity while avoiding failure. Supply–loss theory incorporates root distribution, hydraulic redistribution, cavitation vulnerability, and cavitation reversal. The theory efficiently defines stomatal responses to D, drying soil, and hydraulic vulnerability. Driving the theory with climate predicts drought‐induced loss of plant hydraulic conductance (k), canopy G, carbon assimilation, and productivity. Data lead to the ‘chronic stress hypothesis’ wherein > 60% loss of k increases mortality by multiple mechanisms. Supply–loss theory predicts the climatic conditions that push vegetation over this risk threshold. The theory's simplicity and predictive power encourage testing and application in large‐scale modeling.

Contents

Summary
14

I.
Introduction
14

II.
The transpiration supply function
15

III.
The transpiration loss function
17

IV.
General properties of the supply–loss theory
19

V.
Variations on the theme
19

VI.
Predicting responses to climate
21

VII.
Implications for productivity and mortality: the chronic stress hypothesis
22

VIII.
Conclusion
24

Acknowledgements
24

References
24
When do plant radiations influence community assembly? The importance of historical contingency in the race for niche space
Authors: Tanentzap Andrew J. , Brandt Angela J. , Smissen Rob D. , Heenan Peter B. , Fukami Tadashi , Lee William G.
Published: March 2015

Plant radiations are widespread but their influence on community assembly has rarely been investigated. Theory and some evidence suggest that radiations can allow lineages to monopolize niche space when founding species arrive early into new bioclimatic regions and exploit ecological opportunities. These early radiations may subsequently reduce niche availability and dampen diversification of later arrivals.

We tested this hypothesis of time‐dependent lineage diversification and community dominance using the alpine flora of New Zealand. We estimated ages of 16 genera from published phylogenies and determined their relative occurrence across climatic and physical gradients in the alpine zone. We used these data to reconstruct occupancy of environmental space through time, integrating palaeoclimatic and palaeogeological changes.

Our analysis suggested that earlier‐colonizing lineages encountered a greater availability of environmental space, which promoted greater species diversity and occupancy of niche space. Genera that occupied broader niches were subsequently more dominant in local communities. An earlier time of arrival also contributed to greater diversity independently of its influence in accessing niche space.

We suggest that plant radiations influence community assembly when they arise early in the occupancy of environmental space, allowing them to exclude later‐arriving colonists from ecological communities by niche preemption.
Functional MRI of music emotion processing in frontotemporal dementia
Authors: Agustus Jennifer L. , Mahoney Colin J. , Downey Laura E. , Omar Rohani , Cohen Miriam , White Mark J. , Scott Sophie K. , Mancini Laura , Warren Jason D.
Published: March 2015

Frontotemporal dementia is an important neurodegenerative disorder of younger life led by profound emotional and social dysfunction. Here we used fMRI to assess brain mechanisms of music emotion processing in a cohort of patients with frontotemporal dementia (n = 15) in relation to healthy age‐matched individuals (n = 11). In a passive‐listening paradigm, we manipulated levels of emotion processing in simple arpeggio chords (mode versus dissonance) and emotion modality (music versus human emotional vocalizations). A complex profile of disease‐associated functional alterations was identified with separable signatures of musical mode, emotion level, and emotion modality within a common, distributed brain network, including posterior and anterior superior temporal and inferior frontal cortices and dorsal brainstem effector nuclei. Separable functional signatures were identified post‐hoc in patients with and without abnormal craving for music (musicophilia): a model for specific abnormal emotional behaviors in frontotemporal dementia. Our findings indicate the potential of music to delineate neural mechanisms of altered emotion processing in dementias, with implications for future disease tracking and therapeutic strategies.
Modeling effects of cerebellar and basal ganglia lesions on adaptation and anticipation during sensorimotor synchronization
Authors: van der Steen M.C. (Marieke) , Schwartze Michael , Kotz Sonja A. , Keller Peter E.
Published: March 2015

This study addressed the role of subcortical brain structures in temporal adaptation and anticipation during sensorimotor synchronization. The performance of patients with cerebellar or basal ganglia lesions was compared with that of healthy control participants on tasks requiring the synchronization of drum strokes with adaptive and tempo‐changing auditory pacing sequences. The precision of sensorimotor synchronization was generally lower in patients relative to controls (i.e., variability of asynchronies was higher in patients), although synchronization accuracy (mean asynchrony) was commensurate. A computational model of adaptation and anticipation (ADAM) was used to examine potential sources of individual differences in precision by estimating participants’ use of error correction, temporal prediction, and the amount of variability associated with central timekeeping and peripheral motor processes. Parameter estimates based on ADAM indicate that impaired precision was attributable to increased variability of timekeeper and motor processes as well as to reduced temporal prediction in both patient groups. Adaptive processes related to continuously applied error correction were, by contrast, intact in patients. These findings highlight the importance of investigating how subcortical structures, including the cerebellum and basal ganglia, interact with a broader network of cortical regions to support temporal adaptation and anticipation during sensorimotor synchronization.
Dance and the brain: a review
Authors: Karpati Falisha J. , Giacosa Chiara , Foster Nicholas E.V. , Penhune Virginia B. , Hyde Krista L.
Published: March 2015

Dance is a universal form of human expression that offers a rich source for scientific study. Dance provides a unique opportunity to investigate brain plasticity and its interaction with behavior. Several studies have investigated the behavioral correlates of dance, but less is known about the brain basis of dance. Studies on dance observation suggest that long‐ and short‐term dance training affect brain activity in the action observation and simulation networks. Despite methodological challenges, the feasibility of conducting neuroimaging while dancing has been demonstrated, and several brain regions have been implicated in dance execution. Preliminary work from our laboratory suggests that long‐term dance training changes both gray and white matter structure. This article provides a critical summary of work investigating the neural correlates of dance. It covers functional neuroimaging studies of dance observation and performance as well as structural neuroimaging studies of expert dancers. To stimulate ongoing dialogue between dance and science, future directions in dance and brain research as well as implications are discussed. Research on the neuroscience of dance will lead to a better understanding of brain–behavior relationships and brain plasticity in experts and nonexperts and can be applied to the development of dance‐based therapy programs.
Effects of musically cued gait training in Parkinson's disease: beyond a motor benefit
Authors: Bella Simone Dalla , Benoit Charles‐Etienne , Farrugia Nicolas , Schwartze Michael , Kotz Sonja A.
Published: March 2015

Auditory stimulation via rhythmic cues can be used successfully in the rehabilitation of motor function in patients with motor disorders. A prototypical example is provided by dysfunctional gait in patients with idiopathic Parkinson's disease (PD). Coupling steps to external rhythmic cues (the beat of music or the sounds of a metronome) leads to long‐term motor improvements, such as increased walking speed and greater stride length. These effects are likely to be underpinned by compensatory brain mechanisms involving cerebellar–thalamocortical networks. Because these areas are also involved in perceptual and motor timing, parallel improvement in timing tasks is expected in PD beyond purely motor benefits. In keeping with this idea, we report here recent behavioral data showing beneficial effects of musically cued gait training (MCGT) on gait performance (i.e., increased stride length and speed), perceptual timing (e.g., discriminating stimulus durations), and sensorimotor timing abilities (i.e., in paced tapping tasks) in PD patients. Particular attention is paid to individual differences in timing abilities in PD, thus paving the ground for an individualized MCGT‐based therapy.
Promises of formal and informal musical activities in advancing neurocognitive development throughout childhood
Authors: Putkinen Vesa , Tervaniemi Mari , Saarikivi Katri , Huotilainen Minna
Published: March 2015

Adult musicians show superior neural sound discrimination when compared to nonmusicians. However, it is unclear whether these group differences reflect the effects of experience or preexisting neural enhancement in individuals who seek out musical training. Tracking how brain function matures over time in musically trained and nontrained children can shed light on this issue. Here, we review our recent longitudinal event‐related potential (ERP) studies that examine how formal musical training and less formal musical activities influence the maturation of brain responses related to sound discrimination and auditory attention. These studies found that musically trained school‐aged children and preschool‐aged children attending a musical playschool show more rapid maturation of neural sound discrimination than their control peers. Importantly, we found no evidence for pretraining group differences. In a related cross‐sectional study, we found ERP and behavioral evidence for improved executive functions and control over auditory novelty processing in musically trained school‐aged children and adolescents. Taken together, these studies provide evidence for the causal role of formal musical training and less formal musical activities in shaping the development of important neural auditory skills and suggest transfer effects with domain‐general implications.
Acquisition and reacquisition of motor coordination in musicians
Authors: Furuya Shinichi , Altenmüller Eckart
Published: March 2015

Precise control of movement timing plays a key role in musical performance. This motor skill requires coordination across multiple joints and muscles, which is acquired through extensive musical training from childhood. However, extensive training has a potential risk of causing neurological disorders that impair fine motor control, such as task‐specific tremor and focal dystonia. Recent technological advances in measurement and analysis of biological data, as well as noninvasive manipulation of neuronal activities, have promoted the understanding of computational and neurophysiological mechanisms underlying acquisition, loss, and reacquisition of dexterous movements through musical practice and rehabilitation. This paper aims to provide an overview of the behavioral and neurophysiological basis of motor virtuosity and disorder in musicians, representative extremes of human motor skill. We also report novel evidence of effects of noninvasive neurorehabilitation that combined transcranial direct‐current stimulation and motor rehabilitation over multiple days on musician's dystonia, which offers a promising therapeutic means.
Musical pleasure and reward: mechanisms and dysfunction
Authors: Zatorre Robert J.
Published: March 2015

Most people derive pleasure from music. Neuroimaging studies show that the reward system of the human brain is central to this experience. Specifically, the dorsal and ventral striatum release dopamine when listening to pleasurable music, and activity in these structures also codes the reward value of musical excerpts. Moreover, the striatum interacts with cortical mechanisms involved in perception and valuation of musical stimuli. Recent studies have begun to explore individual differences in the way that this complex system functions. Development of a questionnaire for music reward experiences has allowed the identification of separable factors associated with musical pleasure, described as music‐seeking, emotion‐evocation, mood regulation, sensorimotor, and social factors. Applying this questionnaire to a large sample uncovered approximately 5% of the population with low sensitivity to musical reward in the absence of generalized anhedonia or depression. Further study of this group revealed that there are individuals who respond normally both behaviorally and psychophysiologically to rewards other than music (e.g., monetary value) but do not experience pleasure from music despite normal music perception ability and preserved ability to identify intended emotions in musical passages. This specific music anhedonia bears further study, as it may shed light on the function and dysfunction of the reward system.
Environmental filtering increases in intensity at both ends of climatic gradients, though driven by different factors, across woody vegetation types of the southwest USA
Authors: Butterfield Bradley J.
Published: March 2015

Species distributions are theorized to be more intensively constrained by abiotic factors in severe than in benign environments. A similar concept can be applied to assemblages of species: environmental filtering is expected to increase in intensity in colder and drier environments. To assess the filtering effects of climate on vegetation at a regional scale, climate niche values were estimated for 338 woody species across 93 vegetation types from arid sub‐tropical to alpine ecosystems of the southwest USA. The standardized range and spacing of climatic niche values in each vegetation type – used as estimates of the intensity of climatic and micro‐environmental filtering, respectively – were correlated with the mean niche values of those vegetation types – used as surrogates for climatic gradients – in order to assess how filtering of vegetation composition varies along broad climatic gradients. The range of climatic niche values was narrower than expected in most vegetation types, indicating significant climatic filtering, with frost having the strongest average effect. Niche spacing differed little from null expectations. Variation in the intensity of climatic filtering along gradients of the same climate variable was primarily asymmetrical, and provided support for the hypothesis that abiotic filtering is most intense in cold and growing season dry environments. However, filtering patterns of at least one climatic factor along gradients of other climatic factors ran counter to the trend of increasing filter intensity in cold or dry environments. In other words, climatic factors exhibited interactive effects on vegetation filtering, often in antagonistic ways. The majority of these interactions were compatible with interspecific niche relationships that correspond with anatomical and physiological tradeoffs among drought, frost and heat tolerances. Filtering patterns and interspecific tradeoffs are likely to vary across taxa and biomes, and application of the methods presented here could help to explain such variation.
Dendritic network structure and dispersal affect temporal dynamics of diversity and species persistence
Authors: Seymour Mathew , Fronhofer Emanuel A. , Altermatt Florian
Published: March 2015

Landscape connectivity structure, specifically the dendritic network structure of rivers, is expected to influence community diversity dynamics by altering dispersal patterns, and subsequently the unfolding of species interactions. However, previous comparative and experimental work on dendritic metacommunities has studied diversity mostly from an equilibrium perspective. Here we investigated the effect of dendritic versus linear network structure on local (α‐diversity), among (β‐diversity) and total (γ‐diversity) temporal species community diversity dynamics. Using a combination of microcosm experiments, which allowed for active dispersal of 14 protists and a rotifer species, and numerical analyses, we demonstrate the general importance of spatial network configuration and basic life history tradeoffs as driving factors of different diversity patterns in linear and dendritic systems. We experimentally found that community diversity patterns were shaped by the interaction of dispersal within the networks and local species interactions. Specifically, α‐diversity remained higher in dendritic networks over time, especially at highly connected sites. β‐diversity was initially greater in linear networks, due to increased dispersal limitation, but became more similar to β‐diversity in dendritic networks over time. Comparing the experimental results with a neutral metacommunity model we found that dispersal and network connectivity alone may, to a large extent, explain α‐ and β‐diversity dynamics. However, additional mechanisms, such as variation in carrying capacity and competition–colonization tradeoffs, were needed in the model to capture the detailed temporal diversity dynamics of the experiments, such as a general decline in γ‐diversity and long‐term dynamics in α‐diversity.
Parallel effects of temperature on the male cricket calling song, phonotaxis of the female and the auditory responses of the L3 neurone
Authors: Navia Benjamin , Burden Christina , Steely Tori , Hasegawa Helen , Cha Esther , Henson Shandelle M. , Stout John , Atkins Gordon
Published: March 2015

Sender–receiver coupling is a fundamental aspect of sexual communication systems, especially when the signal must travel over significant distances. In the cricket Acheta domesticus L., both the syllable period of the calling songs of males and the syllable periods that are most attractive to females are negatively correlated with temperature. However, the range of syllable periods that females respond to phonotactically extends beyond the range of males' calling songs at all temperatures tested. In habitats occupied by crickets, surface temperatures of the ground vary considerably. The cricket's body temperature changes rather quickly based on the amount of direct solar radiation encountered (7 °C in 1 min). The responses by females to calling songs with syllable periods outside of the males' range might be advantageous in countering the effects of local variations in temperature caused by variations in the microhabitat. A temperature shift in the response to syllable period of the L3 auditory neurone parallels the temperature shift seen in the phonotactic response over a similar temperature range. These similarities support the model of the involvement of L3 in the phonotactic response and its modulation by temperature.
Automated Fish Detection in Underwater Images Using Shape‐Based Level Sets
Authors: Ravanbakhsh Mehdi , Shortis Mark R. , Shafait Faisal , Mian Ajmal , Harvey Euan S. , Seager James W.
Published: March 2015

Underwater stereo‐video systems are widely used for the measurement of fish. However, the effectiveness of stereo‐video measurement has been limited because most operational systems still rely on a human operator. In this paper an automated approach for fish detection, using a shape‐based level‐sets framework, is presented. Knowledge of the shape of fish is modelled by principal component analysis (PCA). The Haar classifier is used for precise localisation of the fish head and snout in the image, which is vital information for close‐proximity initialisation of the shape model. The approach has been tested on underwater images representing a variety of challenging situations typical of the underwater environment, such as background interference and poor contrast boundaries. The results obtained demonstrate that the approach is capable of overcoming these difficulties and capturing the fish outline to sub‐pixel accuracy.