bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increased transgenerational epigenetic variation, but not predictable epigenetic variants, after environmental exposure in two apomictic dandelion lineages
Authors: Preite Veronica , Oplaat Carla , Biere Arjen , Kirschner Jan , van der Putten Wim H. , Verhoeven Koen J. F. 
Published: February 2018

AbstractDNA methylation is one of the mechanisms underlying epigenetic modifications. DNA methylations can be environmentally induced and such induced modifications can at times be transmitted to successive generations. However, it remains speculative how common such environmentally induced transgenerational DNA methylation changes are and if they persist for more than one offspring generation. We exposed multiple accessions of two different apomictic dandelion lineages of the Taraxacum officinale group (Taraxacum alatum and T. hemicyclum) to drought and salicylic acid (SA) treatment. Using methylation‐sensitive amplified fragment length polymorphism markers (MS‐AFLPs) we screened anonymous methylation changes at CCGG restriction sites throughout the genome after stress treatments and assessed the heritability of induced changes for two subsequent unexposed offspring generations. Irrespective of the initial stress treatment, a clear buildup of heritable DNA methylation variation was observed across three generations, indicating a considerable background rate of heritable epimutations. Less evidence was detected for environmental effects. Drought stress showed some evidence for accession‐specific methylation changes, but only in the exposed generation and not in their offspring. By contrast, SA treatment caused an increased rate of methylation change in offspring of treated plants. These changes were seemingly undirected resulting in increased transgenerational epigenetic variation between offspring individuals, but not in predictable epigenetic variants. While the functional consequences of these MS‐AFLP‐detected DNA methylation changes remain to be demonstrated, our study shows that (1) stress‐induced transgenerational DNA methylation modification in dandelions is genotype and context‐specific; and (2) inherited environmental DNA methylation effects are mostly undirected and not targeted to specific loci.
Selection by parasitoid females among closely related hosts based on volatiles: Identifying relevant chemical cues
Authors: Fors Lisa , Mozuraitis Raimondas , Blažytė‐Čereškienė Laima , Verschut Thomas A. , Hambäck Peter A. 
Published: February 2018

AbstractParasitoid fitness is influenced by the ability to overcome host defense strategies and by the ability of parasitoid females to select high‐quality host individuals. When females are unable to differentiate among hosts, their fitness will decrease with an increasing abundance of resistant hosts. To understand the effect of mixed host populations on female fitness, it is therefore necessary to investigate the ability of female parasitoids to select among hosts. Here, we used behavioral assays, headspace volatile collection, and electrophysiology to study the ability of Asecodes parviclava to use olfactory cues to select between a susceptible host (Galerucella calmariensis) and a resistant host (Galerucella pusilla) from a distance. Our studies show that parasitoid females have the capacity to distinguish the two hosts and that the selection behavior is acquired through experiences during earlier life stages. Further, we identified two volatiles (α‐terpinolene and [E]‐β‐ocimene) which amounts differ between the two plant–herbivore systems and that caused behavioral and electrophysiological responses. The consequence of this selection behavior is that females have the capacity to avoid laying eggs in G. pusilla, where the egg mortality is higher due to much stronger immune responses toward A. parviclava than in larvae of G. calmariensis.
Patterns of musculoskeletal growth and dimensional changes associated with selection and developmental plasticity in domestic and wild strain turkeys
Authors: Stover Kristin K. , Weinreich Daniel M. , Roberts Thomas J. , Brainerd Elizabeth L. 
Published: February 2018

AbstractDomestication is a type of experimental evolution in which humans have artificially selected for specific desired traits. Selected strain animals can be utilized to identify correlated responses by comparing them to the wild strain. In particular, domestic turkeys have been selected for increased body mass and high‐growth rate, most significantly over the past 60 years. Yet it remains unclear how artificial selection has affected the morphology and evolution of the musculoskeletal system as a whole. Here, we compare growth rate over 21 weeks, hind limb bone scaling across ontogeny via in vivo CT scanning, and muscle proportions in wild and domestic turkeys to identify differences in structural scaling and the potential contributions of selection and developmental plasticity to whole‐organism morphology. The domestic turkeys grew at a higher rate (0.14 kg/day vs. 0.05 kg/day) and reached over 3 times the body mass of wild birds. Comparing the proportional muscle masses in adult turkeys, only the trunk had a greater mass ratio in the domestic turkey, driven solely by M. pectoralis (2.8 times larger). The proportional increase in only breast meat and no other muscles highlights the surgical precision attainable with artificial selection. The domestic turkey femur and tibiotarsus displayed increases in polar moment of area, apparently maintaining torsional strength as body mass increased. The lack of dimensional change in the more vertically held tarsometatarsus is consistent with the pattern expected due to developmental plasticity. These results from the domestic turkey emphasize that there are morphological limits to preserving the balance between growth and function, and varying rates of trait evolution can further complicate this equilibrium.
Incubation temperature impacts nestling growth and survival in an open‐cup nesting passerine
Authors: Ospina Emilie A. , Merrill Loren , Benson Thomas J. 
Published: February 2018

AbstractFor oviparous species such as birds, conditions experienced while in the egg can have long‐lasting effects on the individual. The impact of subtle changes in incubation temperature on nestling development, however, remains poorly understood, especially for open‐cup nesting species with altricial young. To investigate how incubation temperature affects nestling development and survival in such species, we artificially incubated American robin (Turdus migratorius) eggs at 36.1°C (“Low” treatment) and 37.8°C (“High” treatment). Chicks were fostered to same‐age nests upon hatching, and we measured mass, tarsus, and wing length of experimental nestlings and one randomly selected, naturally incubated (“Natural”), foster nest‐mate on days 7 and 10 posthatch. We found significant effects of incubation temperature on incubation duration, growth, and survival, in which experimentally incubated nestlings had shorter incubation periods (10.22, 11.50, and 11.95 days for High, Low, and Natural eggs, respectively), and nestlings from the Low treatment were smaller and had reduced survival compared to High and Natural nestlings. These results highlight the importance of incubation conditions during embryonic development for incubation duration, somatic development, and survival. Moreover, these findings indicate that differences in incubation temperature within the natural range of variation can have important carryover effects on growth and survival in species with altricial young.
Subtle variation in size and shape of the whole forewing and the red band among co‐mimics revealed by geometric morphometric analysis in Heliconius butterflies
Authors: Rossato Dirleane O. , Boligon Danessa , Fornel Rodrigo , Kronforst Marcus R. , Gonçalves Gislene L. , Moreira Gilson R. P. 
Published: February 2018

AbstractHeliconius are unpalatable butterflies that exhibit remarkable intra‐ and interspecific variation in wing color pattern, specifically warning coloration. Species that have converged on the same pattern are often clustered in Müllerian mimicry rings. Overall, wing color patterns are nearly identical among co‐mimics. However, fine‐scale differences exist, indicating that factors in addition to natural selection may underlie wing phenotype. Here, we investigate differences in shape and size of the forewing and the red band in the Heliconius postman mimicry ring (H. erato phyllis and the co‐mimics H. besckei, H. melpomene burchelli, and H. melpomene nanna) using a landmark‐based approach. If phenotypic evolution is driven entirely by predation pressure, we expect nonsignificant differences among co‐mimics in terms of wing shape. Also, a reinforcement of wing pattern (i.e., greater similarity) could occur when co‐mimics are in sympatry. We also examined variation in the red forewing band because this trait is critical for both mimicry and sexual communication. Morphometric results revealed significant but small differences among species, particularly in the shape of the forewing of co‐mimics. Although we did not observe greater similarity when co‐mimics were in sympatry, nearly identical patterns provided evidence of convergence for mimicry. In contrast, mimetic pairs could be distinguished based on the shape (but not the size) of the red band, suggesting an “advergence” process. In addition, sexual dimorphism in the red band shape (but not size) was found for all lineages. Thus, we infer that natural selection due to predation by birds might not be the only mechanism responsible for variation in color patterns, and sexual selection could be an important driver of wing phenotypic evolution in this mimicry ring.
Nesting strategies and disease risk in necrophagous beetles
Authors: Fialho Verônica Saraiva , Rodrigues Vinícius Barros , Elliot Simon Luke 
Published: February 2018

AbstractWhile the effects of carcass decomposition on microorganisms have been demonstrated in recent years, little is known of how this impacts necrophagous insects. A common assumption is that insects that exploit carcasses are exposed to a high density of potentially harmful microorganisms, but no field data have so far validated this. Necrophagous beetles such as the Scarabaeinae have complex nesting behaviors with elaborate parental care. So here, we begin to explore whether this conjunction of life history and nesting behavior represents an adaptive response to the threat posed by microbes in these environments, mainly by entomopathogens. We evaluated the density and distribution of fungi and bacteria from soil near the carcasses, and their ability to infect and kill insects that are in contact with this soil during the decomposition process. Our data showed an increase in the density and activity of opportunistic or facultative pathogens during the apex of decomposition, when there is a predominance of necrophagous insects. Meanwhile, the survivorship of bait insects decreased when in contact with soil from this period of decomposition, indicating a potential risk of infection. However, the density and activity of these microorganisms decreased with distance from the carcass, mainly with depth, which would benefit tunneller beetles in particular. We have thus provided the first field data to show that necrophagous insects are indeed exposed to high densities of potentially harmful microorganisms. Furthermore, we propose that some parental care strategies may have arisen not only as a response to competition, but also as adaptations that reduce the risks of disease. Although we have focused on carrion feeders, we suggest that the same occurs with coprophagous beetles, as both carrion and dung are nutrient‐rich resources.
The effects of allospecific mitochondrial genome on the fitness of northern redbelly dace (Chrosomus eos)
Authors: Angers Bernard , Leung Christelle , Vétil Romain , Deremiens Léo , Vergilino Roland 
Published: February 2018

AbstractInstantaneous mitochondrial introgression events allow the disentangling of the effects of hybridization from those of allospecific mtDNA. Such process frequently occurred in the fish Chrosomus eos, resulting in cybrid individuals composed of a C. eos nuclear genome but with a C. neogaeus mtDNA. This provides a valuable model to address the fundamental question: How well do introgressed individuals perform in their native environment? We infer where de novo production of cybrids occurred to discriminate native environments from those colonized by cybrids in 25 sites from two regions (West‐Qc and East‐Qc) in Quebec (Canada). We then compared the relative abundance of wild types and cybrids as a measure integrating both fitness and de novo production of cybrids. According to mtDNA variation, 12 introgression events are required to explain the diversity of cybrids. Five cybrid lineages could not be associated with in situ introgression events. This includes one haplotype carried by 93% of the cybrids expected to have colonized West‐Qc. These cybrids also displayed a nearly complete allopatric distribution with wild types. We still inferred de novo production of cybrids at seven sites, that accounted for 70% of the cybrids in East‐Qc. Wild‐type and cybrid individuals coexist in all East‐Qc sites while cybrids were less abundant. Allopatry of cybrids restricted to the postglacial expansion suggests the existence of higher fitness for cybrids in specific conditions, allowing for the colonization of different environments and expanding the species’ range. However, allospecific mtDNA does not provide a higher fitness to cybrids in their native environment compared to wild types, making the success of an introgressed lineage uncertain.
Latent source mining in FMRI via restricted Boltzmann machine
Authors: Hu Xintao , Huang Heng , Peng Bo , Han Junwei , Liu Nian , Lv Jinglei , Guo Lei , Guo Christine , Liu Tianming 
Published: February 2018

AbstractBlind source separation (BSS) is commonly used in functional magnetic resonance imaging (fMRI) data analysis. Recently, BSS models based on restricted Boltzmann machine (RBM), one of the building blocks of deep learning models, have been shown to improve brain network identification compared to conventional single matrix factorization models such as independent component analysis (ICA). These models, however, trained RBM on fMRI volumes, and are hence challenged by model complexity and limited training set. In this article, we propose to apply RBM to fMRI time courses instead of volumes for BSS. The proposed method not only interprets fMRI time courses explicitly to take advantages of deep learning models in latent feature learning but also substantially reduces model complexity and increases the scale of training set to improve training efficiency. Our experimental results based on Human Connectome Project (HCP) datasets demonstrated the superiority of the proposed method over ICA and the one that applied RBM to fMRI volumes in identifying task‐related components, resulted in more accurate and specific representations of task‐related activations. Moreover, our method separated out components representing intermixed effects between task events, which could reflect inherent interactions among functionally connected brain regions. Our study demonstrates the value of RBM in mining complex structures embedded in large‐scale fMRI data and its potential as a building block for deeper models in fMRI data analysis.
The impact of correction on MP2RAGE cortical T1 and apparent cortical thickness at 7T
Authors: Haast Roy A.M. , Ivanov Dimo , Uludağ Kâmil 
Published: February 2018

AbstractDetermination of cortical thickness using MRI has often been criticized due to the presence of various error sources. Specifically, anatomical MRI relying on T1 contrast may be unreliable due to spatially variable image contrast between gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF). Especially at ultra‐high field (≥ 7T) MRI, transmit and receive B1‐related image inhomogeneities can hamper correct classification of tissue types. In the current paper, we demonstrate that residual
(transmit) inhomogeneities in the T1‐weighted and quantitative T1 images using the MP2RAGE sequence at 7T lead to biases in cortical thickness measurements. As expected, post‐hoc correction for the spatially varying
profile reduced the apparent T1 values across the cortex in regions with low
, and slightly increased apparent T1 in regions with high
. As a result, improved contrast‐to‐noise ratio both at the GM‐CSF and GM‐WM boundaries can be observed leading to more accurate surface reconstructions and cortical thickness estimates. Overall, the changes in cortical thickness ranged between a 5% decrease to a 70% increase after
correction, reducing the variance of cortical thickness values across the brain dramatically and increasing the comparability with normative data. More specifically, the cortical thickness estimates increased in regions characterized by a strong decrease of apparent T1 after
correction in regions with low
due to improved detection of the pial surface. The current results suggest that cortical thickness can be more accurately determined using MP2RAGE data at 7T if
inhomogeneities are accounted for.
Continuous blood purification ameliorates clinical signs and corrects the plasma phospholipid levels of patients with multiple organ dysfunction syndromes
Authors: Wen Wei , Wang Kun , Jiang Zhi‐Ming , Zhang Zhong‐Hui , Zhou Lei 
Published: February 2018

BackgroundMultiple organ dysfunction syndromes (MODS) is reported as a leading cause of mortality in intensive care units. Recently, continuous blood purification (CBP) has been mostly applied for MODS treatment. Thus, the purpose of this study was to investigate the effects of CBP on plasma phospholipid level in patients with MODS.MethodsA total of 126 patients with MODS and 120 healthy people were collected. The serum cytokine levels, blood biochemical parameters, and blood gas indexes were detected, and the correlation among phospholipid compounds with serum cytokine levels, blood biochemical parameters, and blood gas indexes was analyzed.ResultsBefore CBP, levels of body temperature, RR, HR, CVP, IL‐6, IL‐10, TNF‐α, BUN, SCr, PaCO2, SM747, and LPC540 were obviously higher, and pH, HCO3‐, PaO2, SaO2, PE750, PI885, PC792, PC826, PC830, PC854, PC802, and PG747 were lower in the MODS group than those in the control group. During CBP, the MODS group had gradually declined RR, CVP, levels of IL‐6, IL‐10 and TNF‐α, BUN, SCr, PaCO2, SM747, and LPC540 and increased HCO3‐, PaO2 and SaO2, PE750, PI885, PC792, PC826, PC830, PC854, PC802, and PG747. Besides, levels of PE750, PI885, PC792, PC826, PC830, PC854, PC802, and PG747 had an obvious negative correlation with levels of TNF‐α, IL‐10, IL‐6, BUN, SCr, and PaCO2, and a significant positive correlation with levels of HCO3‐, PaO2, and SaO2.ConclusionCBP could effectively ameliorate clinical signs of patients with MODS and correct the plasma phospholipid levels.
Antibodies against H3 and H4 histones from the sera of HIV‐infected patients catalyze site‐specific degradation of these histones
Authors: Baranova Svetlana V. , Dmitrenok Pavel S. , Zubkova Anastasiya D. , Ivanisenko Nikita V. , Odintsova Elena S. , Buneva Valentina N. , Nevinsky Georgy A. 
Published: February 2018

AbstractHistones and their posttranslational modified forms play pivotal roles in chromatin functioning and gene transcription. Also, histones are harmful when they enter the intercellular space; their administration to animals results in systemic inflammatory and toxic responses. Autoantibodies having enzymatic activities (abzymes) are the specific feature of several autoimmune and viral diseases. Electrophoretically homogeneous IgGs containing no canonical proteases were purified from sera of HIV‐infected patients by using several affinity chromatographies. In contrast to known canonical proteases, Abs from HIV‐infected patients hydrolyzed exclusively only histones but no other control globular proteins. The H3 and H4 histone cleavage sites by antihistone IgGs were determined by matrix‐assisted laser desorption/ionization mass spectrometry for the first time. Two clusters of H3 hydrolysis contain major (↕) and minor (*) cleavage sites: 18‐K*Q*LA↕TK*A↕AR*KS↕A*P‐30 and 34‐G*VK*KPHR*YRPGTVA*L*R‐50. H4 histone has only 1 cluster of cleavage sites containing additionally moderate (↓) cleavage sites: 15‐A↕KR↕HR↕KVLR↓D*NIQ↓GIT*K‐31. Sites of these histones cleavage correspond mainly to their known epitopes. It was surprising that most of the cleavage sites of histones are involved in the interaction with DNA of nucleosome core. Because histones act as damage‐associated molecules, abzymes against H3 and H4 can play important role in pathogenesis of AIDs and probably other viral and immune diseases.
Toward a universal quantum QSPR operator
Authors: Carbó‐Dorca Ramon 
Published: February 2018

AbstractThis article presents a discussion about the formalism, which might be associated to a general Quantum quantitative structure–properties relations operator, appearing in a Boltzmann‐like exponential form, which is based in turn on the definition of the concept of thermal voltage, applied to thermally scaled electronic density functions. Three practical numerical examples are presented, corresponding to the calculation of the polarization angle in assorted chiral molecules, the estimation of fish toxicity for perchlorobenzene within the set of chlorobenzenes and a typical quantum QSAR study on the popular Cramer steroid set.
Kidney function and use of nonsteroidal anti-inflammatory drugs among elderly people: a cross-sectional study on potential hazards for an at risk population
Authors: Modig Sara , Elmståhl Sölve 
Published: February 2018

AbstractBackground Renal elimination normally decreases with age. Nonsteroidal antiinflammatory drugs (NSAIDs) carry a risk of additional kidney damage. Objective The aims of this study were to assess the prevalence of NSAIDs in the elderly (aged ≥ 65) population in Sweden, explore reasons for any possible differences in the level of use and assess their kidney functions. Setting Data were obtained from the cohort study Good Aging in Skåne, Sweden. Patients aged 65 or more were included. Methods Medication lists were collected as well as variables such as cognition and education levels. Glomerular filtration rate was estimated from creatinine and cystatin C. Descriptive statistics and multiple linear regression analysis were used. Main outcome measure: NSAID use among the general elderly population. Results A total of 1798 patients were included. Approximately six percent (n = 105) of the people in the study group were using NSAIDs and of those 82 (78%) bought NSAIDs over the counter (OTC). 42% of those buying NSAIDs OTC showed an estimated glomerular filtration rate below 60 ml/min/1.73 m2. Education level did not affect the use of nonsteroidal anti-inflammatory drugs, nor did age. NSAIDs were more commonly used than other recommended analgesics. Conclusion Many people are unaware of the risks associated with the use of NSAIDs. The findings imply that the frailest elderly use NSAIDs to the same extent as the younger elderly do. It is important that information about safety of these drugs be communicated to both patients and healthcare professionals.