bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interspecific and intraspecific comparisons reveal the importance of evolutionary context in sunfish brain form divergence
Authors: Axelrod Caleb J. , Laberge Frédéric , Robinson Beren W. 
Published: January 2021

AbstractHabitats can select for specialized phenotypic characteristics in animals. However, the consistency of evolutionary responses to particular environmental conditions remains difficult to predict. One trait of great ecological importance is brain form, which is expected to vary between habitats that differ in their cognitive requirements. Here, we compared divergence in brain form and oral jaw size across a common littoral–pelagic ecological axis in two sunfishes at both the intraspecific and interspecific levels. Brain form differed between habitats at every level of comparison; however, divergence was inconsistent, despite consistent differences in oral jaw size. Pumpkinseed and bluegill species differed in cerebellum, optic tectum and olfactory bulb size. These differences are consistent with a historical ecological divergence because they did not manifest between littoral and pelagic ecotypes within either species, suggesting constraints on changes to these regions over short evolutionary time scales. There were also differences in brain form between conspecific ecotypes, but they were inconsistent between species. Littoral pumpkinseed had larger brains than their pelagic counterpart, and littoral bluegill had smaller telencephalons than their pelagic counterpart. Inconsistent brain form divergence between conspecific ecotypes of pumpkinseed and bluegill sharing a common littoral–pelagic habitat axis suggests that contemporary ecological conditions and historic evolutionary context interact to influence evolutionary changes in brain form in fishes.
Frequency of vateritic otoliths and potential consequences for marine survival in hatchery‐reared Atlantic salmon
Authors: Austad Benedikte , Vøllestad L. Asbjørn , Foldvik Anders 
Published: January 2021

AbstractOtoliths are inner‐ear structures of all teleost fish with functional importance for hearing and balance. The otoliths usually consist of aragonite, a polymorph of calcium carbonate, but may also take the form partly or entirely of vaterite, a different polymorph of calcium carbonate. Vateritic otoliths occur sporadically in wild fish, but with a higher frequency in hatchery‐reared fish. Abnormal otoliths have direct consequences for the inner‐ear functions of fish and may be a symptom of environmental stress. In this study, the authors assess the differences in the frequency of abnormal otoliths and degree of abnormality (% vaterite) for different groups of hatchery‐reared Atlantic salmon (Salmo salar) smolt and adults. The groups differed in parental broodstock origin (number of generations in hatchery) and treatment temperature. Smolt from the same groups were also released to complete their ocean migration. The otoliths of the returning and recaptured adults were subsequently extracted to assess the difference in frequency and degree of abnormality between the adults and the smolt from corresponding groups. Return rate varied among groups (0.2%–2.6%). The frequency of vateritic otoliths was high (11.4%–64.4%) and differed among smolt groups. The lowest return rates corresponded with the highest frequency of abnormal otoliths for the groups, suggesting that abnormal otoliths may have negative consequences for marine survival. Furthermore, indications of an effect of fast growth on the formation of abnormal otoliths were found for only one of the experimental groups, and for none of the groups after correcting for Type 1 error. This contradicts previous reports, suggesting rapid growth as the main cause of abnormal otoliths. Adult return rates were generally low, but abnormal otoliths were common, with high coverage (% vaterite).
Exposure to a common urban pollutant affects the survival and swimming behaviour of creek chub (Semotilus atromaculatus)
Authors: Bunt Christopher M. , Jacobson Bailey 
Published: January 2021

AbstractAnthropogenic effects on the aquatic environment are ever present and ever increasing and while a plethora of aquatic contaminants are known to affect fishes, one ubiquitous and increasingly prevalent world‐wide urban runoff pollutant is frequently disregarded, and that is pet waste. While dog waste has been identified as a significant factor contributing to bacteria and nutrient loading within receiving waters and the associated water quality changes are known to affect fishes, the impact of uncollected dog faeces on urban fish populations has never been directly investigated. In this study we exposed creek chub (Semotilus atromaculatus), a widespread tolerant stream minnow, to various realistic concentrations of dog waste as simulated urban park runoff testing both fresh and dried dog faeces in both stagnant and aerated water for 96 h to investigate the impact on fish survival and behaviour. Creek chub percentage mortality increased significantly relative to controls and across an exposure gradient and was likely caused by anoxic conditions. Survivors were initially smaller while those that died were initially larger and presented with abnormal abdominal subdermal lesions post‐exposure. Additional indicators of physiological stress included significantly increased rates of aquatic surface respiration and changes in flume test derived swimming motivation metrics with increased exposure concentrations. Both mortality and behavioural responses were alleviated by aeration. Furthermore, trials with fresh and dried faeces differed only in time‐to‐death and swimming metrics where results from dried trials were similar to those from aerated experiments. Results demonstrated the impact that the global dog waste management problem can have on aquatic communities with effects on creek chub likely to be more severe for less pollution‐tolerant species and also likely to be exacerbated under future scenarios that consider climate change and increased urbanization.
Genetic homogeneity coupled with morphometric variability suggests high phenotypic plasticity in the sea louse Caligus rogercresseyi (Boxshall and Bravo, 2000), infecting farmed salmon (Salmo salar) along a wide latitudinal range in southern Chile
Authors: González María Teresa , Leiva Natalia Verónica , Sepúlveda Fabiola , Asencio Gladys , Baeza Juan Antonio 
Published: January 2021

AbstractThe sea louse Caligus rogercresseyi is the most important pathogen causing “caligidosis” in the Chilean salmon industry. In this study, using cox1 gene, we evaluate the genetic variation of C. rogercresseyi from farmed Salmo salar along a latitudinal range (40°–52°S) in south Chile to determine whether morphological differences are explained by genetic or environmental factors. Female parasites were randomly collected from S. salar at five farms. Body variation was examined using multivariate analyses and genetic heterogeneity was explored with AMOVA. C. rogercresseyi exhibited significant morphometric variability among sites and parasites collected from >54°S were the longest ones. Parasites did not show genetic structure among farms. Thus, C. rogercresseyi infesting salmons is panmictic along an extensive latitudinal range in south Chile. The same genetic pattern can be explained by the frequent movement of parasitized S. salar among farms in that region. Phenotypic plasticity in parasites could be explained by natural or aquaculture‐mediated environment variability. C. rogercreseyi from 54°S could favor the local spread of this disease, suggesting an immediate health risk for the recent salmon industry in that region. Further research is required to confirm genetic homogeneity of this parasite along its geographical distribution using more powerful markers (e.g. SNPs).
Clinical and Neuroimaging Manifestations of Erdheim–Chester Disease: A Review
Authors: Garg Neeta , Lavi Efrat Saraf 
Published: January 2021

ABSTRACTErdheim–Chester disease (ECD) is a rare disorder characterized by accumulation of non‐Langerhans cell histiocytes in multiple organs. The clinical manifestations are protean and vary from asymptomatic focal disease to potentially fatal multisystem disorder. The commonest presentation is symmetric osterosclerotic lesions of lower extremity long bones; other organs, including cardiovascular, nervous, and endocrine system may be affected. Central nervous system involvement can occur in up to 50% cases and is associated with poor prognosis. The disease pathogenesis involves organ involvement secondary to histiocytic infiltration and systemic inflammation driven by Th1 cytokine activation. The recent discovery of activating mutations in proto‐oncogene B‐rapidly accelerated fibrosarcoma (BRAF) V600E and other genes involved in mitogen‐activated protein kinase (MAPK) pathways has led to redefinition of ECD as a myeloid neoplastic disorder. The diagnosis requires histochemical and molecular analysis of histiocytes in tissue biopsies in patients with compatible clinical and imaging features. The treatment options include interferon‐alpha, anakinra, and immunosuppressive therapies. Better understanding of disease pathogenesis has led to development of novel targeted and effective therapies including BRAF and MEK inhibitors. The rarity of the disease and variable clinical features and course often results in diagnostic errors and delays. Rare primary neurological presentation can occur mimicking CNS inflammatory, neoplastic, or demyelinating disorders. We report an unusual case of ECD presenting with progressive encephalopathy and ataxia along with multifocal brainstem and cerebellar lesions. A comprehensive review of clinical and neuroimaging features and immunohistochemical and molecular characteristic of ECD are presented along with review of neuroimaging findings in two previously reported cases.
Changes of bolus properties and the triggering of swallowing in healthy humans
Authors: Kochi Izumi , Takei Eri , Maeda Rumiko , Ito Kayoko , Magara Jin , Tsujimura Takanori , Kulvanich Sirima , Inoue Makoto 
Published: January 2021

AbstractThere is wide variation in chewing behaviours, even among healthy humans. Further, the way in which humans determine swallowing initiation when chewing solid foods remains unclear. The current study sought to investigate how the bolus properties change over time during chewing, and to clarify which factors affect chewing and swallowing behaviours, including swallowing initiation, in healthy humans. Twenty‐four healthy volunteers were instructed to chew 8 g of steamed rice and spit it out at 50%, 100% and 150% of their own chewing duration, defined as the time of chewing from onset of the first chewing cycle to onset of the first swallow. Chewing and swallowing behaviours were monitored and determined by visual inspection of video recordings. The physical properties such as hardness, cohesiveness and adhesiveness as well as water content of the bolus were measured. In each subject, maximum bite force, tongue pressure and stimulated salivary flow rate were also measured. Hardness gradually decreased, and the cohesiveness and water content of the bolus did not change up to 50% of chewing duration, followed by a slight but significant increase. The adhesiveness of the bolus rapidly decreased at the beginning of chewing. Chewing duration was significantly related to stimulated salivary flow rate; greater salivary flow rate was associated with shorter chewing duration. Variation of chewing duration and swallowing initiation was not dependent on bolus properties during the chewing of steamed rice, but mainly depended on the surface lubrication of the bolus.
What is boredom proneness? A comparison of three characterizations
Authors: Tam Katy Y. Y. , van Tilburg Wijnand A. P. , Chan Christian S. 
Published: January 2021

AbstractObjectiveBoredom proneness is associated with various problematic behaviors and mental health issues. Despite its wide‐ranging implication, boredom proneness as a trait‐like construct suffers from conceptual ambiguity and measurement issues. We examined whether boredom proneness represents individual differences in (a) the frequency of getting bored, (b) the intensity of boredom, and/or (c) a holistic perception of life being boring (perceived life boredom).MethodAcross Study 1 (U.S. Sample, N = 495; HK Sample, N = 231) and Study 2 (N = 608), we tested the construct validity of boredom proneness by estimating its association with measures of the three possible characterizations (convergent validity), and examined to what extent associations between boredom proneness and variables relevant to well‐being (e.g., life satisfaction, psychological distress) could be reproduced with the three potential characterizations (concurrent validity).ResultsResults suggest that each of the three characterizations represents some aspect of boredom proneness, and they generally reproduced boredom proneness' associations with other variables. Among them, perceived life boredom had the strongest convergent and concurrent validity.ConclusionOur findings provide novel insights into the characterization of boredom proneness and its hitherto poorly understood relationship with psychological well‐being.
Employee narcissism and promotability prospects
Authors: Nevicka Barbara , Sedikides Constantine 
Published: January 2021

AbstractIntroductionNarcissistic individuals often rise to positions of influence, but how so? Upward mobility in formal hierarchies is frequently contingent upon supervisory evaluations. We examined the relation between employee narcissism and supervisor promotability ratings, testing predictions from the display of power perspective (narcissism will positively predict promotability due to higher perceived power) and impression management perspective (narcissism will positively predict promotability due to self‐promotion).MethodIn two multisource studies involving employees and their supervisors from diverse organizations (S1: Nemployees = 166; Nsupervisors = 93; S2: Nemployees = 128; Nsupervisors = 85), we measured employee narcissism (S1, S2), employee sense of power, employee impression management tactics toward the supervisor (S2), and employee promotability as rated by supervisors (S1–S2). Further, in an experiment (S3: N = 181), we tested the causal effect of employee sense of power on promotability.ResultsResults favored the display of power perspective. Although narcissism predicted both higher self‐promotion toward the supervisor and greater sense of power, it was the latter that explained the positive relation between employee narcissism and promotability ratings.ConclusionEmployees high on narcissism act as if they have more power in organizations, and thus, demonstrate behavior that would be expected in higher level positions. The findings help to explain narcissistic individuals' rise through the ranks.
Preschoolers' and Third Graders' Understanding of the Causal Relations of Emotions and Behaviors in Moral Situations
Authors: Hasegawa Mari 
Published: January 2021

AbstractThis study aimed to determine whether children understand relationships between emotions and later behaviors in moral situations. Japanese preschoolers and third graders listened to stories featuring characters feeling happy or sad after behaving immorally, or after avoiding immoral behaviors using willpower. Two immoral behaviors were used in two studies: pushing a child off a swing and stealing another child's doughnuts. In both studies, participants judged whether characters feeling happiness or sadness in the moral conflict situations would later behave immorally. The stories of Study 1 were presented side‐by‐side, whereas the stories of Study 2 used forced‐choice questions. Children understood the relationships between emotions and behaviors when asked forced‐choice questions. However, preschoolers had difficulty explaining their reasoning. Preschoolers correctly answered questions related to negative feelings after deviation rather than positive feelings after avoiding deviation. The findings show that young children have some understanding of the correlation between emotions and later moral behavior, although they have more difficulty understanding positive feelings after avoiding deviation than negative feelings after deviation.
Freshwater zooplankton microbiome composition is highly flexible and strongly influenced by the environment
Authors: Eckert Ester M. , Anicic Nikoleta , Fontaneto Diego 
Published: January 2021

AbstractThe association with microbes in plants and animals is known to be beneficial for host's survival and fitness, but the generality of the effect of the microbiome is still debated. For some animals, similarities in microbiome composition reflect taxonomic relatedness of the hosts, a pattern termed phylosymbiosis. The mechanisms behind the pattern could be due to co‐evolution and/or to correlated ecological constraints. General conclusions are hampered by the fact that available knowledge is highly dominated by microbiomes from model species. Here, we addressed the issue of the generality of phylosymbiosis by analysing the species‐specificity of microbiomes across different species of freshwater zooplankton, including rotifers, cladocerans, and copepods, coupling field surveys and experimental manipulations. We found that no signal of phylosymbiosis was present, and that the proportion of “core” microbial taxa, stable and consistent within each species, was very low. Changes in food and temperature under laboratory experimental settings revealed that the microbiome of freshwater zooplankton is highly flexible and can be influenced by the external environment. Thus, the role of co‐evolution, strict association, and interaction with microbes within the holobiont concept highlighted for vertebrates, corals, sponges, and other animals does not seem to be supported for all animals, at least not for freshwater zooplankton. Zooplankton floats in the environment where both food and bacteria that can provide help in digesting such food are available. In addition, there is probably redundancy for beneficial bacterial functions in the environment, not allowing a strict host‐microbiome association to originate and persist.
PaeA (YtfL) protects from cadaverine and putrescine stress in Salmonella Typhimurium and E. coli
Authors: Iwadate Yumi , Ramezanifard Rouhallah , Golubeva Yekaterina A. , Fenlon Luke A. , Slauch James M. 
Published: January 2021

AbstractSalmonella and E. coli synthesize, import, and export cadaverine, putrescine, and spermidine to maintain physiological levels and provide pH homeostasis. Both low and high intracellular levels of polyamines confer pleiotropic phenotypes or lethality. Here, we demonstrate that the previously uncharacterized inner membrane protein PaeA (YtfL) is required for reducing cytoplasmic cadaverine and putrescine concentrations. We identified paeA as a gene involved in stationary phase survival when cells were initially grown in acidic medium, in which they produce cadaverine. The paeA mutant is also sensitive to putrescine, but not to spermidine or spermine. Sensitivity to external cadaverine in stationary phase is only observed at pH > 8, suggesting that the polyamines need to be deprotonated to passively diffuse into the cell cytoplasm. In the absence of PaeA, intracellular polyamine levels increase and the cells lose viability. Degradation or modification of the polyamines is not relevant. Ectopic expression of the known cadaverine exporter, CadB, in stationary phase partially suppresses the paeA phenotype, and overexpression of PaeA in exponential phase partially complements a cadB mutant grown in acidic medium. These data support the hypothesis that PaeA is a cadaverine/putrescine exporter, reducing potentially toxic levels under certain stress conditions.
A CRISPR/Cas9‐mediated in situ complementation method for Phytophthora sojae mutants
Authors: Qiu Min , Li Yaning , Ye Wenwu , Zheng Xiaobo , Wang Yuanchao 
Published: January 2021

AbstractPhytophthora sojae is an important model species for oomycete functional genomics research. Recently, a CRISPR/Cas9‐mediated genome‐editing technology has been successfully established in P. sojae, which has been rapidly and widely applied in oomycete research. However, there is an emerging consensus in the biological community that a complete functional gene research system is needed such as developed in the investigations in functional complementation carried out in this study. We report the development of an in situ complementation method for accurate restoration of the mutated gene. We targeted a regulatory B‐subunit of protein phosphatase 2A (PsPP2Ab1) to verify this knockout and subsequent complementation system. We found that the deletion of PsPP2Ab1 in P. sojae leads to severe defects in vegetative hyphal growth, soybean infection, and loss of the ability to produce sporangia. Subsequently, the reintroduction of PsPP2Ab1 into the knockout mutant remedied all of the deficiencies. This study demonstrates the successful implementation of an in situ complementation system by CRISPR/Cas9, which will greatly accelerate functional genomics research of oomycetes in the post‐genomic era.
Characterisation of early ultrastructural changes in the cerebral white matter of CADASIL small vessel disease using high‐pressure freezing/freeze‐substitution
Authors: Rajani Rikesh M. , Dupré Nicolas , Domenga‐Denier Valérie , Van Niel Guillaume , Heiligenstein Xavier , Joutel Anne 
Published: January 2021

AbstractAimsThe objective of this study was to elucidate the early white matter changes in CADASIL small vessel disease.MethodsWe used high‐pressure freezing and freeze substitution (HPF/FS) in combination with high‐resolution electron microscopy (EM), immunohistochemistry and confocal microscopy of brain specimens from control and CADASIL (TgNotch3R169C) mice aged 4–15 months to study white matter lesions in the corpus callosum.ResultsWe first optimised the HPF/FS protocol in which samples were chemically prefixed, frozen in a sample carrier filled with 20% polyvinylpyrrolidone and freeze‐substituted in a cocktail of tannic acid, osmium tetroxide and uranyl acetate dissolved in acetone. EM analysis showed that CADASIL mice exhibit significant splitting of myelin layers and enlargement of the inner tongue of small calibre axons from the age of 6 months, then vesiculation of the inner tongue and myelin sheath thinning at 15 months of age. Immunohistochemistry revealed an increased number of oligodendrocyte precursor cells, although only in older mice, but no reduction in the number of mature oligodendrocytes at any age. The number of Iba1 positive microglial cells was increased in older but not in younger CADASIL mice, but the number of activated microglial cells (Iba1 and CD68 positive) was unchanged at any age.ConclusionWe conclude that early WM lesions in CADASIL affect first and foremost the myelin sheath and the inner tongue, suggestive of a primary myelin injury. We propose that those defects are consistent with a hypoxic/ischaemic mechanism.