bluuebunny/crossref_metadata_2025 huggingface dataset:
Climate change impacts on mismatches between phytoplankton blooms and fish spawning phenology
Authors: Asch Rebecca G. , Stock Charles A. , Sarmiento Jorge L.
Published: June 2019

Substantial interannual variability in marine fish recruitment (i.e., the number of young fish entering a fishery each year) has been hypothesized to be related to whether the timing of fish spawning matches that of seasonal plankton blooms. Environmental processes that control the phenology of blooms, such as stratification, may differ from those that influence fish spawning, such as temperature‐linked reproductive maturation. These different controlling mechanisms could cause the timing of these events to diverge under climate change with negative consequences for fisheries. We use an earth system model to examine the impact of a high‐emissions, climate‐warming scenario (RCP8.5) on the future spawning time of two classes of temperate, epipelagic fishes: “geographic spawners” whose spawning grounds are defined by fixed geographic features (e.g., rivers, estuaries, reefs) and “environmental spawners” whose spawning grounds move responding to variations in environmental properties, such as temperature. By the century's end, our results indicate that projections of increased stratification cause spring and summer phytoplankton blooms to start 16 days earlier on average (±0.05 days SE) at latitudes >40°N. The temperature‐linked phenology of geographic spawners changes at a rate twice as fast as phytoplankton, causing these fishes to spawn before the bloom starts across >85% of this region. “Extreme events,” defined here as seasonal mismatches >30 days that could lead to fish recruitment failure, increase 10‐fold for geographic spawners in many areas under the RCP8.5 scenario. Mismatches between environmental spawners and phytoplankton were smaller and less widespread, although sizable mismatches still emerged in some regions. This indicates that range shifts undertaken by environmental spawners may increase the resiliency of fishes to climate change impacts associated with phenological mismatches, potentially buffering against declines in larval fish survival, recruitment, and fisheries. Our model results are supported by empirical evidence from ecosystems with multidecadal observations of both fish and phytoplankton phenology.
Asymmetry in above‐ and belowground productivity responses to N addition in a semi‐arid temperate steppe
Authors: Wang Jing , Gao Yingzhi , Zhang Yunhai , Yang Junjie , Smith Melinda D. , Knapp Alan K. , Eissenstat David M. , Han Xingguo
Published: June 2019

Nitrogen (N) enrichment often increases aboveground net primary productivity (ANPP) of the ecosystem, but it is unclear if belowground net primary productivity (BNPP) track responses of ANPP. Moreover, the frequency of N inputs may affect primary productivity but is rarely studied. To assess the response patterns of above‐ and belowground productivity to rates of N addition under different addition frequencies, we manipulated the rate (0–50 g N m−2 year−1) and frequency (twice vs. monthly additions per year) of NH4NO3 inputs for six consecutive years in a temperate grassland in northern China and measured ANPP and BNPP from 2012 to 2014. In the low range of N addition rates, BNPP showed the greatest negative response and ANPP showed the greatest positive responses with increases in N addition (<10 g N m−2 year−1). As N addition increased beyond 10 g N m−2 year−1, increases in ANPP dampened and decreases in BNPP ceased altogether. The response pattern of net primary productivity (combined above‐ and belowground; NPP) corresponded more closely to ANPP than to BNPP. The N effects on BNPP and BNPP/NPP (fBNPP) were not dependent on N addition frequency in the range of N additions typically associated with N deposition. BNPP was more sensitive to N addition frequency than ANPP, especially at low rates of N addition. Our findings provide new insights into how plants regulate carbon allocation to different organs with increasing N rates and changing addition frequencies. These root response patterns, if incorporated into Earth system models, may improve the predictive power of C dynamics in dryland ecosystems in the face of global atmospheric N deposition.
Machine‐Learning Methods for Water Table Depth Prediction in Seasonal Freezing‐Thawing Areas
Authors: Zhao Tianxing , Zhu Yan , Ye Ming , Mao Wei , Zhang Xiaoping , Yang Jinzhong , Wu Jingwei
Published: June 2019

Long‐term and accurate predictions of regional groundwater hydrology are important for maintaining environmental sustainability in arid agricultural areas that experience seasonal freezing and thawing where serious water‐saving measurements are used. In this study, we firstly developed a machine‐learning method by integrating a multivariate time series controlled auto‐regressive method and the ridge regression method (CAR‐RR) for water table depth modeling. We applied and evaluated this model in the Hetao Irrigation District, located in northwest China where the freezing‐thawing period is 5 months long. To train and validate the model, we used monthly data of water diversion, precipitation, evaporation, and drainage from 1995 to 2013. The CAR‐RR model yielded more accurate results than the support vector regression (SVR) and multiple linear regression (MLR) models did in the validation period. To extend the model applicability during freezing‐thawing periods, we included additional temperature information. We compared results obtained using temperature only during the freezing‐thawing period with results obtained without temperature, which showed that the input data of the temperature during the freezing‐thawing period significantly improved the model accuracy. To resolve the problem of capturing the peaks and troughs of CAR‐RR, we further developed an integrated CAR‐SVR model to consider the nonlinearity. The optimal model (CAR‐SVR) was then used to predict the water table depth under future water‐saving measurements. It demonstrated that water diversion was the most important factor affecting the water table depth. A water table depth with less than 3.64 billion m3 water diversion will result in risks of environment problems.
Simulation of Groundwater Level in Ephemeral Streams with an Improved Groundwater Hydraulics Model
Authors: Liu Qianqian , Hanati Gulimire , Danierhan Sulitan , Zhang Yin , Zhang Zhiping
Published: June 2019

As a component of arid ecosystems, groundwater plays an important role in plant growth; therefore, it is essential to use deterministic models to reconstruct the process of groundwater level change. Typically, the linearized solution of the one‐dimensional (1‐D) Boussinesq equation yields acceptable performance in simulating transient conditions over short recharge periods in ephemeral stream systems, but the ability of this solution to simulate multiyear changes in groundwater levels is limited. In this study, an improved groundwater hydraulics (GH‐D2) model is built based on the groundwater hydraulics (GH) solution of the 1‐D Boussinesq equation to simulate multiyear changes in the groundwater level in ephemeral stream systems. The model is validated in the lower reaches of the Tarim River to simulate groundwater level fluctuations within the scope of influence of the river (300, 500, 750, 1050 m) over a 16‐year period (2000 to 2015). To evaluate the performance of the models, the bias, mean absolute error, root mean squared error, Nash‐Sutcliffe efficiency (NSE), and coefficient of determination (R2) are calculated. The results show that the improved GH‐D2 model, which considers ephemeral streamflow, unsteady flow theory and the delayed response effect of groundwater level changes, performs well in simulating multiyear changes in the groundwater level in the ephemeral stream system. The observed and simulated values of the groundwater level at different river distances are consistent, and the model provides a new basis for multiyear simulations of groundwater level fluctuations in ephemeral stream systems.
Characterization of Dizziness After Lasmiditan Usage: Findings From the SAMURAI and SPARTAN Acute Migraine Treatment Randomized Trials
Authors: Tepper Stewart J. , Krege John H. , Lombard Louise , Asafu‐Adjei Josephine K. , Dowsett Sherie A. , Raskin Joel , Buchanan Andrew S. , Friedman Deborah I.
Published: June 2019

Trial Design

SAMURAI and SPARTAN were double‐blind, placebo‐controlled Phase 3 studies conducted in the United States, as well as the United Kingdom and Germany (SPARTAN only). Individuals with migraine were randomized to receive oral lasmiditan 50 mg (SPARTAN only), 100 mg, 200 mg, or placebo within 4 hours of onset of a migraine attack. The aim of this analysis was to characterize dizziness reported with lasmiditan treatment.

Methods

Data from SAMURAI and SPARTAN were pooled for the current post hoc analyses. Onset time and duration of dizziness were analyzed using descriptive statistics. Subgroup analyses based on presence/absence of dizziness were performed for the endpoints of interference with daily activity, patient global impression of change (PGIC), pain at 2 hours, and most bothersome symptom (MBS) at 2 hours based on adverse events occurring within 2 hours of taking study drug.

Results

Dizziness incidence was as follows: Placebo (N = 1262), 2.9% (0.1% severe); lasmiditan 50 mg (N = 654), 8.6% (0.3% severe); lasmiditan 100 mg (N = 1265), 14.9% (0.7% severe); and lasmiditan 200 mg (N = 1258), 16.8% (1.4% severe). Among participants who received lasmiditan as their first dose, risk factors for dizziness were higher lasmiditan dosage, being non‐Hispanic/Latino, mild or moderate severity of migraine attack, and lower body mass index. The median time to onset of dizziness was generally 30‐40 minutes, and the median duration was 1.5‐2 hours. The presence of dizziness did not appear to have a negative influence on lasmiditan's effect on daily activity, PGIC, freedom from pain, or MBS. Overall, 21 participants experienced vertigo: Lasmiditan 50 mg, n = 2 (0.3%); 100 mg, n = 11 (0.9%); 200 mg, n = 7 (0.6%); and placebo, n = 1 (<0.1%).

Conclusion

The incidence of dizziness with lasmiditan increased with dose. Dizziness was generally mild or moderate in severity and of quick onset and short duration. The presence of dizziness did not influence drug efficacy.
Biogeography of plant root‐associated fungal communities in the North Atlantic region mirrors climatic variability
Authors: Botnen Synnøve Smebye , Davey Marie L. , Aas Anders Bjørnsgaard , Carlsen Tor , Thoen Ella , Heegaard Einar , Vik Unni , Dresch Philipp , Mundra Sunil , Peintner Ursula , Taylor Andy F. S. , Kauserud Håvard
Published: June 2019

Aim

Polar and alpine ecosystems appear to be particularly sensitive to increasing temperatures and the altered precipitation patterns linked to climate change. However, little is currently known about how these environmental drivers may affect edaphic organisms within these ecosystems. In this study, we examined communities of plant root‐associated fungi (RAF) over large biogeographical scales and along climatic gradients in the North Atlantic region in order to gain insights into the potential effects of climate variability on these communities. We also investigated whether selected fungal traits were associated with particular climates.

Locations

Austria, Scotland, Mainland Norway, Iceland, Jan Mayen and Svalbard.

Taxa

Root fungi associated with the ectomycorrhizal and herbaceous plant Bistorta vivipara.

Methods

DNA metabarcoding of the ITS1 region was used to characterize the RAF of 302 whole plant root systems, which were analysed by means of ordination methods and linear modelling. Fungal spore length, width, volume and shape, as well as mycelial exploration type (ET) of ectomycorrhizal (ECM) basidiomycetes were summarized at a community level.

Results

The RAF communities exhibited strong biogeographical structuring, and both compositional variation as well as fungal species richness correlated with annual temperature and precipitation. In accordance with general island biogeography theory, the least species‐rich RAF communities were found on Jan Mayen, a remote and small island in the North Atlantic Ocean. Fungal spores tended to be more elongated with increasing latitude. We also observed a climate effect on which mycelial ET was dominating among the ectomycorrhizal fungi.

Main conclusions

Both geographical and environmental variables were important for shaping root‐associated fungal communities at a North Atlantic scale, including the High Arctic. Fungal OTU richness followed general biogeographical patterns and decreased with decreasing size and/or increasing isolation of the host plant population. The probability of possessing more elongated spores increases with latitude, which may be explained by a selection for greater dispersal capacity among more isolated host plant populations in the Arctic.
Transgressive niche across a salamander hybrid zone revealed by microhabitat analyses
Authors: Ficetola Gentile Francesco , Lunghi Enrico , Cimmaruta Roberta , Manenti Raoul
Published: June 2019

Aim

Hybrid populations can have intermediate, conserved or transgressive niches, compared to the parental species. Fine‐scale analyses can improve our understanding of niche evolution, but information on microhabitat differences between parental species and hybrids is extremely scarce for animal populations. We assessed the pattern and role of niche variation along a hybrid zone, by investigating differences in microhabitat selection between terrestrial cave salamander species (Hydromantes ambrosiiandHydromantes italicus) and their hybrids. We tested whether introgressed populations show intermediate, conserved or transgressive niche, compared to parental species. Furthermore, we compared body condition index (BCI) among individuals observed in different microhabitats (different areas of caves), to assess the potential advantages of exploiting specific microhabitats.

Location

We surveyed ~700 cave sectors in Italy, across the whole range of the two parental species and along their contact zone.

Methods

We recorded salamander distribution and measured microhabitat features influencing salamander distribution: humidity, temperature and incident light. We tested niche differences between parental species and hybrids, and analysed spatial variation of body condition.

Results

We detected significant niche shifts between parental species and hybrids. Introgressed populations showed a transgressive niche and exploited sectors with warmer temperature, lower humidity and more light, compared to the non‐introgressed ones. Introgressed salamanders were better able to exploit the microhabitat conditions that are frequently found nearby cave entrance. For males, BCI was significantly higher in individuals found close to the cave entrance.

Main conclusions

The transgressive niche of hybrids betweenH. ambrosiiandH. italicusindicates niche expansion towards harsh environmental conditions, and such transgressive segregation allows exploiting environments with higher food availability. The ability to exploit dry and warm sectors can provide important advantages to hybrid populations that can better persist under stressful conditions. Transgressive niche can be important for long‐term persistence and evolution within hybrid zones.
A Historical Review of Postponement Research
Authors: Zinn Walter
Published: June 2019

This historical review traces the development of postponement research starting in the fifties. The focus is on seven related themes: connecting form and time postponement, conceptual extensions to postponement, decoupling points, design for postponement, customization and mass customization, factors favoring postponement implementation, and postponement in global settings. Within these themes, the review includes concepts such as postponement costs, decoupling points, part commonality, and the impact of demand correlations on the benefits of postponement. The review suggests that substantial progress has been made in postponement research.
“Good Players” or “Good People”: Masculinities, Mobilities, and Class in Argentinian Rugby
Authors: Fuentes Sebastian , Guinness Daniel
Published: June 2019

Los clubes de elite en Buenos Aires utilizaron el rugby amateur para la formación de la clase y la masculinidad, definiendo a la profesionalización deportiva representada en el popular fútbol como una alteridad moral. Cuando el rugby se profesionalizó internacionalmente en 1995, los clubes reaccionaron de modo defensivo, prohibiendo que quienes habían jugado en el exterior participen en las uniones locales. Examinamos las reacciones de las elites a la profesionalización, las experiencias de los jugadores que regresan del exterior y sus estrategias de (in)movilidad. Son novedosas las articulaciones entre la reproducción de clase local y los sistemas globales en los que participan los jóvenes: la centralidad de los clubes en la formación de experiencias, afectos y valores de las elites; las aspiraciones de movilidad frente a los lazos de amistad y parentesco; y la adaptación de una fuerza disruptiva ‐el profesionalismo‐ en el marco de las relaciones locales de clase y género.
Spreading of alpha‐synuclein – relevant or epiphenomenon?
Authors: Killinger Bryan A. , Kordower Jeffrey H.
Published: June 2019

The intracellular accumulation of misfolded alpha‐synuclein pathology, termed Lewy pathology, throughout the brain is a phenomenon central to Parkinson’s disease pathogenesis. In recent years it has become apparent that Lewy pathology can spread from neuron‐to‐neuron and between interconnected brain regions. Understanding the phenomenon of Lewy pathology propagation holds great promise in its explanatory power to determine the etiology of Parkinson’s disease and related synucleinopathies. However, it remains to be seen if the spread of Lewy pathology is critical for driving this disease. Here we discuss the spreading of Lewy pathology while highlighting some important concepts and experimental observations. We conclude that further studies are required to determine if, and how, the spreading behavior of Lewy pathology is involved in Parkinson’s disease.

image

“This article is part of the Special Issue Synuclein”
The Best of Both Worlds: Accessing Emerging Economies via Developed Markets
Authors: BAE JOON WOO , ELKAMHI REDOUANE , SIMUTIN MIKHAIL
Published: June 2019

A growing body of evidence suggests that the benefits of international diversification via developed markets have declined dramatically. While emerging markets still offer diversification opportunities, their public equity indices capture only a fraction of emerging countries' economic activity. We propose a diversification approach that exploits the global connectedness of developed countries to gain exposure to emerging countries' overall economies rather than their shallow equity markets. In doing so, we demonstrate that developed markets still offer substantial diversification benefits beyond those available through equity indices. Our results suggest that relying on equity indices to assess diversification benefits understates diversification gains.
Ratings Quality and Borrowing Choice
Authors: BADOER DOMINIQUE C. , DEMIROGLU CEM , JAMES CHRISTOPHER M.
Published: June 2019

Past studies document that incentive conflicts may lead issuer‐paid credit rating agencies to provide optimistically biased ratings. In this paper, we present evidence that investors question the quality of issuer‐paid ratings and raise corporate bond yields where the issuer‐paid rating is more positive than benchmark investor‐paid ratings. We also find that some firms with favorable issuer‐paid ratings substitute public bonds with borrowings from informed intermediaries to mitigate the “lemons discount” associated with poor quality ratings. Overall, our results suggest that the quality of issuer‐paid ratings has significant effects on borrowing costs and the choice of debt.
A model for comprehensive oral biological age score with oral and systemic clinical parameters
Authors: He Zhi‐Chao , Sun Chen , Jiang Wei‐Wen
Published: June 2019

Background

Biological age reflects the functional status of an individual. The purpose of the study was to develop a model for estimating oral biological age with oral and systemic parameters.

Methods

A total of 248 subjects who had a routine health check were assessed with oral and general clinical examination. Chi‐square test was performed to screen oral clinical candidate indicators. General parameters were analyzed by Pearson correlation coefficient and principal component analysis to develop a general biological age score. A final comprehensive model of oral biological age score was established by combining oral and general biological age score.

Results

A total of eight oral indicators (mucosal blood blister, mucosal dryness, impacted tooth, missing teeth, residual crowns, dental calculus, gingival hyperemia, and gingival recession) and 10 general clinical indicators (triglyceride, creatinine, blood urea nitrogen, glucose, total cholesterol, mean erythrocyte hemoglobin concentration, mean erythrocyte hemoglobin, uric acid, body weight, and systolic blood pressure) were selected for oral and general biological age score, respectively (r > 0.25, P < 0.05). A model of comprehensive oral biological age score was then formed by principal component analysis: 0.046 triglyceride + 0.010 creatinine + 0.141 blood urea nitrogen + 0.048 glucose + 0.068 total cholesterol + 0.014 mean erythrocyte hemoglobin concentration + 0.082 mean erythrocyte hemoglobin + 0.001 uric acid + 0.020 body weight + 0.005 systolic blood pressure + 0.037 oral biological age score −10.908. The score was increased accordingly with CA.

Conclusion

Oral biological age can be easily estimated clinically by the model of comprehensive oral biological age score using oral and systemic clinical parameters by general practitioners.
Predicting trait emotional intelligence from HEXACO personality: Domains, facets, and the general factor of personality
Authors: Anglim Jeromy , Morse Gavin , Dunlop Patrick D. , Minbashian Amirali , Marty Andrew
Published: June 2019

Objective

The current study provides a comprehensive analysis of the overlap between trait emotional intelligence (EI) and personality. This overlap was examined using the HEXACO personality framework at both the domain and the facet levels, and through varying methods of deriving a general factor of personality (GFP).

Method

A sample of 1,370 Australian adults (51% male, age in years M = 45.5, SD = 11.7, range: 21–71) completed the 200‐item HEXACO Personality Inventory‐Revised and the Modified Assessing Emotions Scale measure of self‐reported Trait EI.

Results

The strongest domain correlations with Total EI emerged for Extraversion (r = .67) followed by Openness (r = .39), Conscientiousness (r = .35), and Agreeableness (r = .26). Large adjusted multiple correlations were obtained when predicting Total EI from HEXACO domains (.74) and facets (.81). The correlations of the GFP and Total EI ranged from .53 to .64 depending on how the GFP was operationalized.

Conclusion

Trait EI is largely captured by the HEXACO personality framework, whereby Extraversion or the GFP provides a rough initial approximation, but composites of domains and facets provide progressively better representations.
Diet is a main source of vitamin D in Finnish pet rabbits (Oryctolagus cuniculus)
Authors: Mäkitaipale Johanna , Sievänen Harri , Sankari Satu , Laitinen‐Vapaavuori Outi
Published: June 2019

During the winter time in Finland, sunlight is inadequate for vitamin D synthesis. Many pet rabbits live as house rabbits with limited outdoor access even during summer and may therefore be dependent on dietary sources of vitamin D. The aims of this study were to report the serum 25‐hydroxyvitamin D concentrations in Finnish pet rabbits and to identify factors that influence vitamin D status. Serum 25‐hydroxyvitamin D concentrations from 140 pet rabbits were determined using a vitamin D enzyme immunoassay (EIA) kit. Eleven rabbits were excluded from the statistical analysis because of unclear dietary data. The remaining 129 rabbits were divided into groups depending on outdoor access during summer (no access n = 26, periodic n = 57, regular n = 46) as well as daily diet: little or no hay and commercial rabbit food ≤1/2 dl (n = 12); a lot of hay and no commercial food daily (n = 23); a lot of hay and commercial food <1 dl (n = 59); a lot of hay and commercial food ≥1 dl (n = 35). The range of serum 25‐hydroxyvitamin D concentration was from 4.5 to 67.5 ng/ml with a mean of 26.1 ng/ml. Statistical general linear model adjusted for weight, age and season indicated that diet was associated with vitamin D concentrations (p = 0.001), but outdoor access during summer was not (p = 0.41). Mean 25‐hydroxyvitamin D concentration was significantly higher in the rabbits receiving a lot of hay and commercial food ≥1 dl (33.9 ± 13.2 ng/ml) than in rabbits in other diet groups (24.0 ± 8.5 ng/ml, 21.7 ± 8.1 ng/ml, and 22.2 ± 18.0 ng/ml, respectively). This investigation showed wide variation in 25‐hydroxyvitamin D concentrations among Finnish pet rabbits. Diet remains a main source since outdoor access seems to be too limited to provide adequate vitamin D synthesis for most of them, and the use of vitamin D supplements is rare.
Harnessing synthetic biology for kelp forest conservation1
Authors: Coleman Melinda A. , Goold Hugh D.
Published: June 2019

Environmental and climatic change is outpacing the ability of organisms to adapt, at an unprecedented level, resulting in range contractions and global ecosystem shifts to novel states. At the same time, scientific advances continue to accelerate, providing never‐before imagined solutions to current and emerging environmental problems. Synthetic biology, the creation of novel and engineered genetic variation, is perhaps the fastest developing and transformative scientific field. Its application to solve extant and emerging environmental problems is vast, at times controversial, and technological advances have outpaced the social, ethical, and practical considerations of its use. Here, we discuss the potential direct and indirect applications of synthetic biology to kelp forest conservation. Rather than advocate or oppose its use, we identify where and when it may play a role in halting or reversing global kelp loss and discuss challenges and identify pathways of research needed to bridge the gap between technological advances and organismal biology and ecology. There is a pressing need for prompt collaboration and dialogue among synthetic biologists, ecologists, and conservationists to identify opportunities for use and ensure that extant research directions are set on trajectories to allow these currently disparate fields to converge toward practical environmental solutions.
Minimal mortality and rapid recovery of the dominant shrub Larrea tridentata following an extreme cold event in the northern Chihuahuan Desert
Authors: Ladwig Laura M. , Collins Scott L. , Krofcheck Dan J. , Pockman William T.
Published: June 2019

Questions

Woody encroachment into grasslands is a worldwide phenomenon partially influenced by climate change, including extreme weather events. Larrea tridentata is a common shrub throughout the warm deserts of North America that has encroached into grasslands over the past 150 years. Physiological measurements suggest that the northern distribution of L. tridentata is limited by cold temperatures; thus extreme winter events may slow or reverse shrub expansion. We tested this limitation by measuring the response of individual L. tridentata shrubs to an extreme winter cold (−31°C) event to assess shrub mortality and rate of recovery of surviving shrubs.

Location

Sevilleta National Wildlife Refuge, Socorro County, New Mexico, USA.

Methods

Canopy dieback and recovery following an extreme cold event were measured for 869 permanently marked individual L. tridentata shrubs in grass–shrub ecotone and shrubland sites. Individual shrubs were monitored for amount of canopy dieback, rate of recovery, and seed set for three growing seasons after the freeze event.

Results

Shrubs rapidly suffered a nearly complete loss of canopy leaf area across all sites. Although canopy loss was high, mortality was low and 99% of shrubs resprouted during the first growing season after the freeze event. Regrowth rates were similar within ecotone and shrubland sites, even when damage by frost was larger in the latter. After three years of recovery, L. tridentata canopies had regrown on average 23–83% of the original pre‐freeze canopy sizes across the sites.

Conclusions

We conclude that isolated extreme cold events may temporarily decrease shrubland biomass but they do not slow or reverse shrub expansion. These events are less likely to occur in the future as regional temperatures increase under climate change.
Disease progression in paediatric‐ and adult‐onset sclerosing cholangitis: Results from two independent Dutch registries
Authors: Joosse Maria E. , Haisma Sjoukje M. , Sterk Marlou F. M. , van Munster Kim N. , Ponsioen Cyriel I. J. , Houwen Roderick H. J. , Koot Bart G. P. , de Meij Tim , van Rheenen Patrick F. , de Koning Barbara A. E.
Published: June 2019

Background & Aims

Sclerosing cholangitis (SC) is a severe liver disease leading to destruction of bile ducts. It is believed to run a milder course in children than in adults. To test this assumption, we evaluated time‐to‐complication curves in two independent paediatric‐onset cohorts from the same geographical area.

Methods

Short‐term disease outcomes were evaluated with an online clinical registry that was filled with data on children with SC diagnosed between 2000 and 2017 and who were followed bi‐annually thereafter. Long‐term disease outcomes were evaluated in a paediatric‐onset subcohort derived from a previously published population‐based study from the Netherlands. Time‐to‐complication in the first cohort was defined as the time from diagnosis until portal hypertension, biliary obstructions and infections, development of malignancy, or liver transplantation, whichever came first. In the second cohort time‐to‐complication was defined as the time until liver transplantation or PSC‐related death.

Results

Median age at diagnosis in the first cohort (n = 86) was 12.3 years. In the first 5 years post‐diagnosis 23% of patients developed complications. The patients in the population‐based study (n = 683) were stratified into those diagnosed before the age of 18 years (‘paediatric‐onset’ subcohort, n = 43) and those diagnosed after the age of 18 years (‘adult‐onset’ subcohort, n = 640). Median age at diagnosis was 14.6 and 40.2 years, respectively. Median time‐to‐complication in the paediatric‐onset and adult‐onset subcohorts was not statistically different.

Conclusion

Paediatric and adult‐onset SC run a similar long‐term disease course. Paediatricians who treat children with SC should monitor them closely to recognize early complications and control long‐term sequelae.
A convolute diversity of the Auriculariales (Agaricomycetes, Basidiomycota) with sphaeropedunculate basidia
Authors: Spirin Viacheslav , Malysheva Vera , Roberts Peter , Trichies Gérard , Savchenko Anton , Larsson Karl‐Henrik
Published: June 2019

Morphological and DNA data show that effused representatives of the Auriculariales (Basidiomycota) with sphaeropedunculate basidia belong to eleven genera of which seven are dealt with in this study. Among them, Myxarium is the largest genus containing 21 accepted species of which nine are reintroduced below and five are described as new. Protodontia is limited to three species only, P. subgelatinosa (the generic type) and two newly described species from Africa. Protoacia is a new monotypic genus for P. delicata, sp. nov., widely distributed on coniferous hosts in Eurasia. Myxariellum is erected for two new species with smooth hymenophore from northwestern North America while Gelacantha is introduced for G. pura, a new species with hydnoid hymenophore from Caucasus. Our data do not confirm the present synonymy of Sebacina sphaerospora with Tremella glaira, and these species are placed in two separate genera – Hydrophana, gen. nov., and Ofella, gen. nov., respectively. A key to European Myxarium and similar‐looking species is included.
Plant species roles in pollination networks: an experimental approach
Authors: Maia Kate P. , Vaughan Ian P. , Memmott Jane
Published: June 2019

Pollination is an important ecosystem service threatened by current pollinator declines, making flower planting schemes an important strategy to recover pollination function. However, ecologists rarely test the attractiveness of chosen plants to pollinators in the field. Here, we experimentally test whether plant species roles in pollination networks can be used to identify species with the most potential to recover plant–pollinator communities. Using published pollination networks, we calculated each plant's centrality and chose five central and five peripheral plant species for introduction into replicate experimental plots. Flower visitation by pollinators was recorded in each plot and we tested the impact of introduced central and peripheral plant species on the pollinator and resident plant communities and on network structure. We found that the introduction of central plant species attracted a higher richness and abundance of pollinators than the introduction of peripheral species, and that the introduced central plant species occupied the most important network roles. The high attractiveness of central species to pollinators, however, did not negatively affect visitation to resident plant species by pollinators. We also found that the introduction of central plant species did not affect network structure, while networks with introduced peripheral species had lower centralisation and interaction evenness than networks with introduced central species. To our knowledge, this is the first time species network roles have been tested in a field experiment. Given that most restoration projects start at the plant community, being able to identify the plants with the highest potential to restore community structure and functioning should be a key goal for ecological restoration.
Bearding the scorpion in his den: desert isopods take risks to validate their ‘landscape of fear’ assessment
Authors: Zaguri Moshe , Hawlena Dror
Published: June 2019

Animals balance the risk of predation against other vital needs by adjusting their spatial behavior to match spatiotemporal variation in predation risk. To map this ‘landscape of fear’, prey use evolutionary rules of thumbs that are associated with the activity and hunting efficiency of predators. In addition, prey acquire perceptual information about the presence, identity and state of potential predators and use these cues to focus their acute anti‐predatory responses. Our goal was to explore if and how prey also use such perceptual information that decays with time to update their spatiotemporal risk assessment. We placed scorpions in freshly dug burrows and recorded the spatial activity and defense behavior of their isopod prey upon encountering the burrows straight after settling the scorpions and seven days later. To corroborate our understanding, we also examined the isopods’ detailed reactions towards deserted scorpion burrows. The isopods reacted defensively to scorpion burrows during their first encounter. After seven days, proportionally more isopods approached the scorpion burrows on their way out for foraging and fewer isopods encountered it on their way back. No changes in the spatial activity were observed towards deserted burrows. In addition, on the eighth day, more isopods entered the risky area near the scorpion burrows when leaving their own burrow than on the first encounter. The results suggest that isopods used predator cues to readjust the ‘landscape of fear’. Yet, rather than avoiding the dangerous areas altogether, the isopods implemented risky inspection behavior, validating whether the danger is actual. Our findings imply that inspection behavior toward predators can be used for future planning of prey spatial activity, offsetting possible ‘information decay costs’.
Cadmium induces reactive oxygen species‐dependent pexophagy in Arabidopsis leaves
Authors: Calero‐Muñoz Nieves , Exposito‐Rodriguez Marino , Collado‐Arenal Aurelio M. , Rodríguez‐Serrano María , Laureano‐Marín Ana M. , Santamaría M. Estrella , Gotor Cecilia , Díaz Isabel , Mullineaux Philip M. , Romero‐Puertas María C. , Olmedilla Adela , Sandalio Luisa M.
Published: June 2019

Cadmium treatment induces transient peroxisome proliferation in Arabidopsis leaves. To determine whether this process is regulated by pexophagy and to identify the mechanisms involved, we analysed time course‐dependent changes in ATG8, an autophagy marker, and the accumulation of peroxisomal marker PEX14a. After 3 hr of Cd exposure, the transcript levels of ATG8h, ATG8c, a, and i were slightly up‐regulated and then returned to normal. ATG8 protein levels also increased after 3 hr of Cd treatment, although an opposite pattern was observed in PEX14. Arabidopsis lines expressing GFP‐ATG8a and CFP‐SKL enabled us to demonstrate the presence of pexophagic processes in leaves. The Cd‐dependent induction of pexophagy was demonstrated by the accumulation of peroxisomes in autophagy gene (ATG)‐related Arabidopsis knockout mutants atg5 and atg7. We show that ATG8a colocalizes with catalase and NBR1 in the electron‐dense peroxisomal core, thus suggesting that NBR1 may be an autophagic receptor for peroxisomes, with catalase being possibly involved in targeting pexophagy. Protein carbonylation and peroxisomal redox state suggest that protein oxidation may trigger pexophagy. Cathepsine B, legumain, and caspase 6 may also be involved in the regulation of pexophagy. Our results suggest that pexophagy could be an important step in rapid cell responses to cadmium.
Inhibition of NADP‐malic enzyme activity by H2S and NO in sweet pepper (Capsicum annuum L.) fruits
Authors: Muñoz‐Vargas María A. , González‐Gordo Salvador , Palma José M. , Corpas Francisco J.
Published: June 2019

NADPH is an essential cofactor in many physiological processes. Fruit ripening is caused by multiple biochemical pathways in which, reactive oxygen and nitrogen species (ROS/RNS) metabolism is involved. Previous studies have demonstrated the differential modulation of nitric oxide (NO) and hydrogen sulfide (H2S) content during sweet pepper (Capsicum annuum L.) fruit ripening, both of which regulate NADP‐isocitrate dehydrogenase activity. To gain a deeper understanding of the potential functions of other NADPH‐generating components, we analyzed glucose‐6‐phosphate dehydrogenase (G6PDH) and 6‐phosphogluconate dehydrogenase (6PGDH), which are involved in the oxidative phase of the pentose phosphate pathway (OxPPP) and NADP‐malic enzyme (NADP‐ME). During fruit ripening, G6PDH activity diminished by 38%, while 6PGDH and NADP‐ME activity increased 1.5‐ and 2.6‐fold, respectively. To better understand the potential regulation of these NADP‐dehydrogenases by H2S, we obtained a 50–75% ammonium‐sulfate‐enriched protein fraction containing these proteins. With the aid of in vitro assays, in the presence of H2S, we observed that, while NADP‐ME activity was inhibited by up to 29–32% using 2 and 5 mM Na2S as H2S donor, G6PDH and 6PGDH activities were unaffected. On the other hand, NO donors, S‐nitrosocyteine (CysNO) and DETA NONOate also inhibited NADP‐ME activity by 35%. These findings suggest that both NADP‐ME and 6PGDH play an important role in maintaining the supply of NADPH during pepper fruit ripening and that H2S and NO partially modulate the NADPH‐generating system.
Evaluating the public health response to a mass bat exposure—Wyoming, 2017
Authors: Cote Andrea , Wallace Ryan M. , Jackson David A. , Said Maria A. , Musgrave Karl , Tran Cuc H. , Van Houten Clayton , Harrist Alexia , Buttke Danielle , Busacker Ashley , Pickens Veronica , Guagliardo Sarah Anne J.
Published: June 2019

Mass bat exposures (MBEs) occur when multiple people are exposed to a bat or a bat colony, often over an extended period. In August 2017, a public health investigation was started in response to an MBE that occurred during May–August 2017 at a national park research station in Wyoming. We identified 176 people who had slept primarily in two lodges (Lodges A and B) at the research station, and successfully contacted 165 (93.8%) of these individuals. Risk assessments (RAs) were administered to all 165 individuals to determine degree and type of exposures to bats (e.g., biting or scratching). Exposure status for research station guests was classified as “non‐exposed,” “low risk” or “high risk,” and counselling was provided to guide post‐exposure prophylaxis (PEP) recommendations. Prior to public health notification and intervention, 19 persons made the decision to pursue PEP. The healthcare‐seeking behaviours of this group were taken to represent outcomes in the absence of public health intervention. (These persons received a RA, and their risk classification was retrospectively assigned.) Approximately 1–2 weeks after conducting the RAs, we conducted a follow‐up survey to determine whether recommendations regarding PEP were ultimately followed. The proportion of individuals that unnecessarily pursued PEP was higher among the 19 individuals that sought health care prior to receiving the RA (p < 0.00001). Among those receiving the RA first, all persons classified as high risk followed public health guidance to seek PEP treatment. Despite this, upon re‐interview, only 21/79 (26.6%) of guests could accurately recall their risk classification, with most people (55.7%) overestimating their risk. Study findings demonstrate that early public health interventions such as RAs can reduce unnecessary use of PEP and that messaging used during rabies counselling should be clear.
Evaluating the risk of tick‐borne relapsing fever among occupational cavers—Austin, TX, 2017
Authors: Campbell Stefanie B. , Klioueva Anna , Taylor Jeff , Nelson Christina , Tomasi Suzanne , Replogle Adam , Kwit Natalie , Sexton Christopher , Schwartz Amy , Hinckley Alison
Published: June 2019

Tick‐borne relapsing fever (TBRF) is a potentially serious spirochetal infection caused by certain species of Borrelia and acquired through the bite of Ornithodoros ticks. In 2017, Austin Public Health, Austin, TX, identified five cases of febrile illness among employees who worked in caves. A cross‐sectional serosurvey and interview were conducted for 44 employees at eight organizations that conduct cave‐related work. Antibodies against TBRF‐causing Borrelia were detected in the serum of five participants, four of whom reported recent illness. Seropositive employees entered significantly more caves (Median 25 [SD: 15] versus Median 4 [SD: 16], p = 0.04) than seronegative employees. Six caves were entered more frequently by seropositive employees posing a potentially high risk. Several of these caves were in public use areas and were opened for tours. Education of area healthcare providers about TBRF and prevention recommendations for cavers and the public are advised.
Infection control practices employed within small animal veterinary practices—A systematic review
Authors: Willemsen Angela , Cobbold Rowland , Gibson Justine , Wilks Kathryn , Lawler Sheleigh , Reid Simon
Published: June 2019

Effective infection control (IC) provides a safe environment for staff, clients and animals of veterinary practices by reducing the risk of nosocomial and zoonotic infections, which are associated with increased hospital stays, costs, morbidity and mortality. An equally important issue arising from nosocomial infection is the loss of trust between the client and the veterinary practice that has potential negative impacts on the veterinary practice in terms of economic risk and the well‐being of staff. Furthermore, an emerging and significant threat, in this context, is antimicrobial resistance. The aim of this systematic review was to critically review published reports that documented current IC practices and evaluated interventions to improve IC practices. A systematic literature search using ten databases to identify papers published over a 20‐year period (February 1996 to February 2016) was conducted for studies that met the inclusion criteria. Included studies were assessed using the PRISMA and STROBE‐Vet statements. A total of 14 of 1,615 identified studies met our inclusion criteria. Infection control practices included hand hygiene, sharps handling, environmental cleaning, personal protective equipment and personnel vaccination. Descriptive studies were the predominant research design for assessing IC compliance. Only three studies were interventions. Compliance with IC protocols was poor and only marginally increased with multimodal educational campaigns. There was significant variation in the implementation of IC by veterinary staff. Workplaces that had IC policies, management support and a staff member supporting their implementation were more likely to embrace good IC. Infection control data in veterinary practices were inconsistently reported and collected. Clearly defining IC and determining prevalence of these practices within the veterinary field is important given the limited research in this area. Further, developing and implementing educational campaigns for this sector is needed.
A Cinematic View of Tissue Microbiology in the Live Infected Host
Authors: Richter-Dahlfors Agneta , Melican Keira
Published: June 2019

Tissue microbiology allows for the study of bacterial infection in the most clinically relevant microenvironment, the living host. Advancements in techniques and technology have facilitated the development of novel ways of studying infection. Many of these advancements have come from outside the field of microbiology. In this article, we outline the progression from bacteriology through cellular microbiology to tissue microbiology, highlighting seminal studies along the way. We outline the enormous potential but also some of the challenges of the tissue microbiology approach. We focus on the role of emerging technologies in the continual development of infectious disease research and highlight future possibilities in our ongoing quest to understand host-pathogen interaction.
The Role of the Type III Secretion System in the Intracellular Lifestyle of Enteric Pathogens
Authors: De Souza Santos Marcela , Orth Kim
Published: June 2019

Several pathogens have evolved to infect host cells from within, which requires subversion of many host intracellular processes. In the case of Gram-negative pathogenic bacteria, adaptation to an intracellular life cycle relies largely on the activity of type III secretion systems (T3SSs), an apparatus used to deliver effector proteins into the host cell, from where these effectors regulate important cellular functions such as vesicular trafficking, cytoskeleton reorganization, and the innate immune response. Each bacterium is equipped with a unique suite of these T3SS effectors, which aid in the development of an individual intracellular lifestyle for their respective pathogens. Some bacteria adapt to reside and propagate within a customized vacuole, while others establish a replicative niche in the host cytosol. In this article, we review the mechanisms by which T3SS effectors contribute to these different lifestyles. To illustrate the formation of a vacuolar and a cytosolic lifestyle, we discuss the intracellular habitats of the enteric pathogens
Salmonella enterica
serovar Typhimurium and
Shigella flexneri
, respectively. These represent well-characterized systems that function as informative models to contribute to our understanding of T3SS-dependent subversion of intracellular processes. Additionally, we present
Vibrio parahaemolyticus
, another enteric Gram-negative pathogen, as an emerging model for future studies of the cytosolic lifestyle.