PeerJ
type: channel
link: https://peerj.com/articles/
description: Articles published in PeerJ
publisher: PeerJ Inc.
publication name: PeerJ
issn: 2167-8359
items: The influence of temperature and photoperiod on the timing of brood onset in hibernating honey bee colonies
items: Reef fish communities are spooked by scuba surveys and may take hours to recover
items: Identification of stem rust resistance genes in wheat cultivars in China using molecular markers
items: Why is nonword reading so variable in adult skilled readers?
items: On the taxonomic status and distribution of African species of Otomops (Chiroptera: Molossidae)
items: Divergent and convergent evolution of housekeeping genes in human–pig lineage
items: The variable monoaminergic outcomes of cleaner fish brains when facing different social and mutualistic contexts
items: High correlation between skin color based on CIELAB color space, epidermal melanocyte ratio, and melanocyte melanin content
items: Water mites (Acari, Hydrachnidia) of riparian springs in a small lowland river valley: what are the key factors for species distribution?
items: The role of gut microbiota in the regulation of standard metabolic rate in female Periplaneta americana

The influence of temperature and photoperiod on the timing of brood onset in hibernating honey bee colonies
type: item
type: AcademicArticle
description: In order to save resources, honey bee (Apis mellifera) colonies in the temperate zones stop brood rearing during winter. Brood rearing is resumed in late winter to build up a sufficient worker force that allows to exploit floral resources in upcoming spring. The timing of brood onset in hibernating colonies is crucial and a premature brood onset could lead to an early depletion of energy reservoirs. However, the mechanisms underlying the timing of brood onset and potential risks of mistiming in the course of ongoing climate change are not well understood. To assess the relative importance of ambient temperature and photoperiod as potential regulating factors for brood rearing activity in hibernating colonies, we overwintered 24 honey bee colonies within environmental chambers. The colonies were assigned to two different temperature treatments and three different photoperiod treatments to disentangle the individual and interacting effects of temperature and photoperiod. Tracking in-hive temperature as indicator for brood rearing activity revealed that increasing ambient temperature triggered brood onset. Under cold conditions, photoperiod alone did not affect brood onset, but the light regime altered the impact of higher ambient temperature on brood rearing activity. Further the number of brood rearing colonies increased with elapsed time which suggests the involvement of an internal clock. We conclude that timing of brood onset in late winter is mainly driven by temperature but modulated by photoperiod. Climate warming might change the interplay of these factors and result in mismatches of brood phenology and environmental conditions.
format: application/pdf
format: text/html
creator: Fabian Nürnberger
creator: Stephan Härtel
creator: Ingolf Steffan-Dewenter
subject: Animal Behavior
subject: Ecology
subject: Entomology
subject: Zoology
subject: Climate Change Biology
description: doi:10.7717/peerj.4801
publisher: PeerJ Inc.
rights: © 2018 Nürnberger et al.
abstract: In order to save resources, honey bee (Apis mellifera) colonies in the temperate zones stop brood rearing during winter. Brood rearing is resumed in late winter to build up a sufficient worker force that allows to exploit floral resources in upcoming spring. The timing of brood onset in hibernating colonies is crucial and a premature brood onset could lead to an early depletion of energy reservoirs. However, the mechanisms underlying the timing of brood onset and potential risks of mistiming in the course of ongoing climate change are not well understood. To assess the relative importance of ambient temperature and photoperiod as potential regulating factors for brood rearing activity in hibernating colonies, we overwintered 24 honey bee colonies within environmental chambers. The colonies were assigned to two different temperature treatments and three different photoperiod treatments to disentangle the individual and interacting effects of temperature and photoperiod. Tracking in-hive temperature as indicator for brood rearing activity revealed that increasing ambient temperature triggered brood onset. Under cold conditions, photoperiod alone did not affect brood onset, but the light regime altered the impact of higher ambient temperature on brood rearing activity. Further the number of brood rearing colonies increased with elapsed time which suggests the involvement of an internal clock. We conclude that timing of brood onset in late winter is mainly driven by temperature but modulated by photoperiod. Climate warming might change the interplay of these factors and result in mismatches of brood phenology and environmental conditions.
bibliographic citation: Nürnberger et al. (2018) The influence of temperature and photoperiod on the timing of brood onset in hibernating honey bee colonies. PeerJ 6:e4801 https://doi.org/10.7717/peerj.4801
date submitted: 2018-01-26
date accepted: 2018-04-30
issued: 2018-05-25
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Nürnberger
  given name: Fabian
author list: Agent
  family name: Härtel
  given name: Stephan
author list: Agent
  family name: Steffan-Dewenter
  given name: Ingolf
doi: 10.7717/peerj.4801
volume: 6
issn: 2167-8359
publication name: PeerJ
publication date: 2018-05-25
copyright: © 2018 Nürnberger et al.
attribution name: Nürnberger et al.

Reef fish communities are spooked by scuba surveys and may take hours to recover
type: item
type: AcademicArticle
description: Ecological monitoring programs typically aim to detect changes in the abundance of species of conservation concern or which reflect system status. Coral reef fish assemblages are functionally important for reef health and these are most commonly monitored using underwater visual surveys (UVS) by divers. In addition to estimating numbers, most programs also collect estimates of fish lengths to allow calculation of biomass, an important determinant of a fish’s functional impact. However, diver surveys may be biased because fishes may either avoid or are attracted to divers and the process of estimating fish length could result in fish counts that differ from those made without length estimations. Here we investigated whether (1) general diver disturbance and (2) the additional task of estimating fish lengths affected estimates of reef fish abundance and species richness during UVS, and for how long. Initial estimates of abundance and species richness were significantly higher than those made on the same section of reef after diver disturbance. However, there was no evidence that estimating fish lengths at the same time as abundance resulted in counts different from those made when estimating abundance alone. Similarly, there was little consistent bias among observers. Estimates of the time for fish taxa that avoided divers after initial contact to return to initial levels of abundance varied from three to 17 h, with one group of exploited fishes showing initial attraction to divers that declined over the study period. Our finding that many reef fishes may disperse for such long periods after initial contact with divers suggests that monitoring programs should take great care to minimise diver disturbance prior to surveys.
format: application/pdf
format: text/html
creator: Michael J. Emslie
creator: Alistair J. Cheal
creator: M. Aaron MacNeil
creator: Ian R. Miller
creator: Hugh P.A. Sweatman
subject: Animal Behavior
subject: Ecology
subject: Marine Biology
description: doi:10.7717/peerj.4886
publisher: PeerJ Inc.
rights: © 2018 Emslie et al.
abstract: Ecological monitoring programs typically aim to detect changes in the abundance of species of conservation concern or which reflect system status. Coral reef fish assemblages are functionally important for reef health and these are most commonly monitored using underwater visual surveys (UVS) by divers. In addition to estimating numbers, most programs also collect estimates of fish lengths to allow calculation of biomass, an important determinant of a fish’s functional impact. However, diver surveys may be biased because fishes may either avoid or are attracted to divers and the process of estimating fish length could result in fish counts that differ from those made without length estimations. Here we investigated whether (1) general diver disturbance and (2) the additional task of estimating fish lengths affected estimates of reef fish abundance and species richness during UVS, and for how long. Initial estimates of abundance and species richness were significantly higher than those made on the same section of reef after diver disturbance. However, there was no evidence that estimating fish lengths at the same time as abundance resulted in counts different from those made when estimating abundance alone. Similarly, there was little consistent bias among observers. Estimates of the time for fish taxa that avoided divers after initial contact to return to initial levels of abundance varied from three to 17 h, with one group of exploited fishes showing initial attraction to divers that declined over the study period. Our finding that many reef fishes may disperse for such long periods after initial contact with divers suggests that monitoring programs should take great care to minimise diver disturbance prior to surveys.
bibliographic citation: Emslie et al. (2018) Reef fish communities are spooked by scuba surveys and may take hours to recover. PeerJ 6:e4886 https://doi.org/10.7717/peerj.4886
date submitted: 2018-02-14
date accepted: 2018-05-11
issued: 2018-05-24
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Emslie
  given name: Michael J.
author list: Agent
  family name: Cheal
  given name: Alistair J.
author list: Agent
  family name: MacNeil
  given name: M. Aaron
author list: Agent
  family name: Miller
  given name: Ian R.
author list: Agent
  family name: Sweatman
  given name: Hugh P.A.
doi: 10.7717/peerj.4886
volume: 6
issn: 2167-8359
publication name: PeerJ
publication date: 2018-05-24
copyright: © 2018 Emslie et al.
attribution name: Emslie et al.

Identification of stem rust resistance genes in wheat cultivars in China using molecular markers
type: item
type: AcademicArticle
description: Wheat stem rust caused by Puccinia graminis f. sp. tritici Eriks. & E. Henn. (Pgt), is a major disease that has been effectively controlled using resistance genes. The appearance and spread of Pgt races such as Ug99, TKTTF, and TTTTF, which are virulent to most stem rust-resistant genes currently deployed in wheat breeding programs, renewed the interest in breeding cultivars resistant to wheat stem rust. It is therefore important to investigate the levels of resistance or vulnerability of wheat cultivars to Pgt races. Resistance to Pgt races 21C3CTHQM, 34MKGQM, and 34C3RTGQM was evaluated in 136 Chinese wheat cultivars at the seedling stage. A total of 124 cultivars (91.2%) were resistant to the three races. Resistance genes Sr2, Sr24, Sr25, Sr26, Sr31, and Sr38 were analyzed using molecular markers closely linked to them, and 63 of the 136 wheat cultivars carried at least one of these genes: 21, 25, and 28 wheat cultivars likely carried Sr2, Sr31, and Sr38, respectively. Cultivars “Kehan 3” and “Jimai 22” likely carried Sr25. None of the cultivars carried Sr24 or Sr26. These cultivars with known stem rust resistance genes provide valuable genetic material for breeding resistant wheat cultivars.
format: application/pdf
format: text/html
creator: Xiaofeng Xu
creator: Depeng Yuan
creator: Dandan Li
creator: Yue Gao
creator: Ziyuan Wang
creator: Yang Liu
creator: Siting Wang
creator: Yuanhu Xuan
creator: Hui Zhao
creator: Tianya Li
creator: Yuanhua Wu
subject: Agricultural Science
subject: Molecular Biology
subject: Plant Science
description: doi:10.7717/peerj.4882
publisher: PeerJ Inc.
rights: © 2018 Xu et al.
abstract: Wheat stem rust caused by Puccinia graminis f. sp. tritici Eriks. & E. Henn. (Pgt), is a major disease that has been effectively controlled using resistance genes. The appearance and spread of Pgt races such as Ug99, TKTTF, and TTTTF, which are virulent to most stem rust-resistant genes currently deployed in wheat breeding programs, renewed the interest in breeding cultivars resistant to wheat stem rust. It is therefore important to investigate the levels of resistance or vulnerability of wheat cultivars to Pgt races. Resistance to Pgt races 21C3CTHQM, 34MKGQM, and 34C3RTGQM was evaluated in 136 Chinese wheat cultivars at the seedling stage. A total of 124 cultivars (91.2%) were resistant to the three races. Resistance genes Sr2, Sr24, Sr25, Sr26, Sr31, and Sr38 were analyzed using molecular markers closely linked to them, and 63 of the 136 wheat cultivars carried at least one of these genes: 21, 25, and 28 wheat cultivars likely carried Sr2, Sr31, and Sr38, respectively. Cultivars “Kehan 3” and “Jimai 22” likely carried Sr25. None of the cultivars carried Sr24 or Sr26. These cultivars with known stem rust resistance genes provide valuable genetic material for breeding resistant wheat cultivars.
bibliographic citation: Xu et al. (2018) Identification of stem rust resistance genes in wheat cultivars in China using molecular markers. PeerJ 6:e4882 https://doi.org/10.7717/peerj.4882
date submitted: 2018-03-16
date accepted: 2018-05-11
issued: 2018-05-24
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Xu
  given name: Xiaofeng
author list: Agent
  family name: Yuan
  given name: Depeng
author list: Agent
  family name: Li
  given name: Dandan
author list: Agent
  family name: Gao
  given name: Yue
author list: Agent
  family name: Wang
  given name: Ziyuan
author list: Agent
  family name: Liu
  given name: Yang
author list: Agent
  family name: Wang
  given name: Siting
author list: Agent
  family name: Xuan
  given name: Yuanhu
author list: Agent
  family name: Zhao
  given name: Hui
author list: Agent
  family name: Li
  given name: Tianya
author list: Agent
  family name: Wu
  given name: Yuanhua
doi: 10.7717/peerj.4882
volume: 6
issn: 2167-8359
publication name: PeerJ
publication date: 2018-05-24
copyright: © 2018 Xu et al.
attribution name: Xu et al.

Why is nonword reading so variable in adult skilled readers?
type: item
type: AcademicArticle
description: When the task is reading nonwords aloud, skilled adult readers are very variable in the responses they produce: a nonword can evoke as many as 24 different responses in a group of such readers. Why is nonword reading so variable? We analysed a large database of reading responses to nonwords, which documented that two factors contribute to this variability. The first factor is variability in graphemic parsing (the parsing of a letter string into its constituent graphemes): the same nonword can be graphemically parsed in different ways by different readers. The second factor is phoneme assignment: even when all subjects produce the same graphemic parsing of a nonword, they vary in what phonemes they assign to the resulting set of graphemes. We consider the implications of these results for the computational modelling of reading, for the assessment of impairments of nonword reading, and for the study of reading aloud in other alphabetically written languages and in nonalphabetic writing systems.
format: application/pdf
format: text/html
creator: Max Coltheart
creator: Anastasia Ulicheva
subject: Cognitive Disorders
subject: Psychiatry and Psychology
subject: Computational Science
description: doi:10.7717/peerj.4879
publisher: PeerJ Inc.
rights: © 2018 Coltheart et al.
abstract: When the task is reading nonwords aloud, skilled adult readers are very variable in the responses they produce: a nonword can evoke as many as 24 different responses in a group of such readers. Why is nonword reading so variable? We analysed a large database of reading responses to nonwords, which documented that two factors contribute to this variability. The first factor is variability in graphemic parsing (the parsing of a letter string into its constituent graphemes): the same nonword can be graphemically parsed in different ways by different readers. The second factor is phoneme assignment: even when all subjects produce the same graphemic parsing of a nonword, they vary in what phonemes they assign to the resulting set of graphemes. We consider the implications of these results for the computational modelling of reading, for the assessment of impairments of nonword reading, and for the study of reading aloud in other alphabetically written languages and in nonalphabetic writing systems.
bibliographic citation: Coltheart et al. (2018) Why is nonword reading so variable in adult skilled readers?. PeerJ 6:e4879 https://doi.org/10.7717/peerj.4879
date submitted: 2018-03-08
date accepted: 2018-05-11
issued: 2018-05-24
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Coltheart
  given name: Max
author list: Agent
  family name: Ulicheva
  given name: Anastasia
doi: 10.7717/peerj.4879
volume: 6
issn: 2167-8359
publication name: PeerJ
publication date: 2018-05-24
copyright: © 2018 Coltheart and Ulicheva
attribution name: Coltheart et al.

On the taxonomic status and distribution of African species of Otomops (Chiroptera: Molossidae)
type: item
type: AcademicArticle
description: Background Free-tailed bats of the genus Otomops are poorly known, and most species are documented from a handful of widely scattered localities. Recently, two allopatric species of Otomops were recognized in continental Africa: Otomops martiensseni (Matschie, 1897) in southern, central and western Africa, and the new species O. harrisoni Ralph et al., 2015 in the northeast and in Yemen. Methods We collected additional samples of Otomops in Kenya and Rwanda where the ranges of these taxa approach one another to clarify their geographic ranges and taxonomic status. Mitochondrial and nuclear intron sequences served to identify and delimit species; we also documented their echolocation call variation and ectoparasite complements. Results Otomops martiensseni, the southern African species, was documented in northern Kenya in Marsabit National Park. O. harrisoni, the northeastern African–Arabian species, was documented in southern Kenya and in a cave in Musanze District, Rwanda. Moreover, individuals of both species were found together at the Musanze cave, establishing them in precise spatial and temporal sympatry. Analyses of mitochondrial and nuclear loci identify no evidence of admixture between these forms, although available samples limit the power of this analysis. Echolocation call differences are also apparent among the three localities we analyzed. Three orders of insects and two families of mites are newly reported as ectoparasites of O. harrisoni. Discussion Our results corroborate species rank for O. harrisoni and establish a zone of potential geographic overlap with O. martiensseni spanning at least 800 km of latitude. The new records establish the species in sympatry in northern Rwanda and add an additional species to the bat faunas of both Kenya and Rwanda. Future studies are needed to understand Otomops roosting requirements and movements, thereby explaining the paucity of known colonies and yielding better estimates of their conservation status. The disc…
format: application/pdf
format: text/html
creator: Bruce D. Patterson
creator: Paul W. Webala
creator: Michael Bartonjo
creator: Julius Nziza
creator: Carl W. Dick
creator: Terrence C. Demos
subject: Biodiversity
subject: Biogeography
subject: Conservation Biology
subject: Taxonomy
subject: Zoology
description: doi:10.7717/peerj.4864
publisher: PeerJ Inc.
rights: © 2018 Patterson et al.
abstract: Background Free-tailed bats of the genus Otomops are poorly known, and most species are documented from a handful of widely scattered localities. Recently, two allopatric species of Otomops were recognized in continental Africa: Otomops martiensseni (Matschie, 1897) in southern, central and western Africa, and the new species O. harrisoni Ralph et al., 2015 in the northeast and in Yemen. Methods We collected additional samples of Otomops in Kenya and Rwanda where the ranges of these taxa approach one another to clarify their geographic ranges and taxonomic status. Mitochondrial and nuclear intron sequences served to identify and delimit species; we also documented their echolocation call variation and ectoparasite complements. Results Otomops martiensseni, the southern African species, was documented in northern Kenya in Marsabit National Park. O. harrisoni, the northeastern African–Arabian species, was documented in southern Kenya and in a cave in Musanze District, Rwanda. Moreover, individuals of both species were found together at the Musanze cave, establishing them in precise spatial and temporal sympatry. Analyses of mitochondrial and nuclear loci identify no evidence of admixture between these forms, although available samples limit the power of this analysis. Echolocation call differences are also apparent among the three localities we analyzed. Three orders of insects and two families of mites are newly reported as ectoparasites of O. harrisoni. Discussion Our results corroborate species rank for O. harrisoni and establish a zone of potential geographic overlap with O. martiensseni spanning at least 800 km of latitude. The new records establish the species in sympatry in northern Rwanda and add an additional species to the bat faunas of both Kenya and Rwanda. Future studies are needed to understand Otomops roosting requirements and movements, thereby explaining the paucity of known colonies and yielding better estimates of their conservation status. The disc…
bibliographic citation: Patterson et al. (2018) On the taxonomic status and distribution of African species of Otomops (Chiroptera: Molossidae). PeerJ 6:e4864 https://doi.org/10.7717/peerj.4864
date submitted: 2018-02-19
date accepted: 2018-05-08
issued: 2018-05-24
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Patterson
  given name: Bruce D.
author list: Agent
  family name: Webala
  given name: Paul W.
author list: Agent
  family name: Bartonjo
  given name: Michael
author list: Agent
  family name: Nziza
  given name: Julius
author list: Agent
  family name: Dick
  given name: Carl W.
author list: Agent
  family name: Demos
  given name: Terrence C.
doi: 10.7717/peerj.4864
volume: 6
issn: 2167-8359
publication name: PeerJ
publication date: 2018-05-24
copyright: © 2018 Patterson et al.
attribution name: Patterson et al.

Divergent and convergent evolution of housekeeping genes in human–pig lineage
type: item
type: AcademicArticle
description: Housekeeping genes are ubiquitously expressed and maintain basic cellular functions across tissue/cell type conditions. The present study aimed to develop a set of pig housekeeping genes and compare the structure, evolution and function of housekeeping genes in the human–pig lineage. By using RNA sequencing data, we identified 3,136 pig housekeeping genes. Compared with human housekeeping genes, we found that pig housekeeping genes were longer and subjected to slightly weaker purifying selection pressure and faster neutral evolution. Common housekeeping genes, shared by the two species, achieve stronger purifying selection than species-specific genes. However, pig- and human-specific housekeeping genes have similar functions. Some species-specific housekeeping genes have evolved independently to form similar protein active sites or structure, such as the classical catalytic serine–histidine–aspartate triad, implying that they have converged for maintaining the basic cellular function, which allows them to adapt to the environment. Human and pig housekeeping genes have varied structures and gene lists, but they have converged to maintain basic cellular functions essential for the existence of a cell, regardless of its specific role in the species. The results of our study shed light on the evolutionary dynamics of housekeeping genes.
format: application/pdf
format: text/html
creator: Kai Wei
creator: Tingting Zhang
creator: Lei Ma
subject: Bioinformatics
subject: Evolutionary Studies
subject: Genetics
description: doi:10.7717/peerj.4840
publisher: PeerJ Inc.
rights: © 2018 Wei et al.
abstract: Housekeeping genes are ubiquitously expressed and maintain basic cellular functions across tissue/cell type conditions. The present study aimed to develop a set of pig housekeeping genes and compare the structure, evolution and function of housekeeping genes in the human–pig lineage. By using RNA sequencing data, we identified 3,136 pig housekeeping genes. Compared with human housekeeping genes, we found that pig housekeeping genes were longer and subjected to slightly weaker purifying selection pressure and faster neutral evolution. Common housekeeping genes, shared by the two species, achieve stronger purifying selection than species-specific genes. However, pig- and human-specific housekeeping genes have similar functions. Some species-specific housekeeping genes have evolved independently to form similar protein active sites or structure, such as the classical catalytic serine–histidine–aspartate triad, implying that they have converged for maintaining the basic cellular function, which allows them to adapt to the environment. Human and pig housekeeping genes have varied structures and gene lists, but they have converged to maintain basic cellular functions essential for the existence of a cell, regardless of its specific role in the species. The results of our study shed light on the evolutionary dynamics of housekeeping genes.
bibliographic citation: Wei et al. (2018) Divergent and convergent evolution of housekeeping genes in human–pig lineage. PeerJ 6:e4840 https://doi.org/10.7717/peerj.4840
date submitted: 2017-12-04
date accepted: 2018-05-03
issued: 2018-05-24
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Wei
  given name: Kai
author list: Agent
  family name: Zhang
  given name: Tingting
author list: Agent
  family name: Ma
  given name: Lei
doi: 10.7717/peerj.4840
volume: 6
issn: 2167-8359
publication name: PeerJ
publication date: 2018-05-24
copyright: ©2018 Wei et al.
attribution name: Wei et al.

The variable monoaminergic outcomes of cleaner fish brains when facing different social and mutualistic contexts
type: item
type: AcademicArticle
description: The monoamines serotonin and dopamine are important neuromodulators present in the central nervous system, known to be active regulators of social behaviour in fish as in other vertebrates. Our aim was to investigate the region-specific brain monoaminergic differences arising when individual cleaners face a client (mutualistic context) compared to when they are introduced to another conspecific (conspecific context), and to understand the relevance of visual assessment compared to the impact of physical contact with any partner. We demonstrated that serotoninergic activity at the diencephalon responds mostly to the absence of physical contact with clients whereas cerebellar dopaminergic activity responds to actual cleaning engagement. We provide first insights on the brain’s monoaminergic (region-specific) response variations, involved in the expression of cleaner fishes’ mutualistic and conspecific behaviour. These results contribute to a better understanding of the monoaminergic activity in accordance to different socio-behavioural contexts.
format: application/pdf
format: text/html
creator: Murilo S. de Abreu
creator: João P.M. Messias
creator: Per-Ove Thörnqvist
creator: Svante Winberg
creator: Marta C. Soares
subject: Animal Behavior
subject: Marine Biology
subject: Neuroscience
description: doi:10.7717/peerj.4830
publisher: PeerJ Inc.
rights: © 2018 De Abreu et al.
abstract: The monoamines serotonin and dopamine are important neuromodulators present in the central nervous system, known to be active regulators of social behaviour in fish as in other vertebrates. Our aim was to investigate the region-specific brain monoaminergic differences arising when individual cleaners face a client (mutualistic context) compared to when they are introduced to another conspecific (conspecific context), and to understand the relevance of visual assessment compared to the impact of physical contact with any partner. We demonstrated that serotoninergic activity at the diencephalon responds mostly to the absence of physical contact with clients whereas cerebellar dopaminergic activity responds to actual cleaning engagement. We provide first insights on the brain’s monoaminergic (region-specific) response variations, involved in the expression of cleaner fishes’ mutualistic and conspecific behaviour. These results contribute to a better understanding of the monoaminergic activity in accordance to different socio-behavioural contexts.
bibliographic citation: de Abreu et al. (2018) The variable monoaminergic outcomes of cleaner fish brains when facing different social and mutualistic contexts. PeerJ 6:e4830 https://doi.org/10.7717/peerj.4830
date submitted: 2018-03-09
date accepted: 2018-05-02
issued: 2018-05-24
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: de Abreu
  given name: Murilo S.
author list: Agent
  family name: Messias
  given name: João P.M.
author list: Agent
  family name: Thörnqvist
  given name: Per-Ove
author list: Agent
  family name: Winberg
  given name: Svante
author list: Agent
  family name: Soares
  given name: Marta C.
doi: 10.7717/peerj.4830
volume: 6
issn: 2167-8359
publication name: PeerJ
publication date: 2018-05-24
copyright: ©2018 De Abreu et al.
attribution name: De Abreu et al.

High correlation between skin color based on CIELAB color space, epidermal melanocyte ratio, and melanocyte melanin content
type: item
type: AcademicArticle
description: Background To treat skin color disorders, such as vitiligo or burns, melanocytes are transplanted for tissue regeneration. However, melanocyte distribution in the human body varies with age and location, making it difficult to select the optimal donor skin to achieve a desired color match. Determining the correlations with the desired skin color measurement based on CIELAB color, epidermal melanocyte numbers, and melanin content of individual melanocytes is critical for clinical application. Method Fifteen foreskin samples from Asian young adults were analyzed for skin color, melanocyte ratio (melanocyte proportion in the epidermis), and melanin concentration. Furthermore, an equation was developed based on CIELAB color with melanocyte ratio, melanin concentration, and the product of melanocyte ratio and melanin concentration. The equation was validated by seeding different ratios of keratinocytes and melanocytes in tissue-engineered skin substitutes, and the degree of fitness in expected skin color was confirmed. Results Linear regression analysis revealed a significant strong negative correlation (r = − 0.847, R2 = 0.717) between CIELAB L* value and the product of the epidermal melanocyte ratio and cell-based melanin concentration. Furthermore, the results showed that an optimal skin color match was achieved by the formula. Discussion We found that L* value was correlated with the value obtained from multiplying the epidermal melanocyte ratio (R) and melanin content (M) and that this correlation was more significant than either L* vs M or L* vs R. This suggests that more accurate prediction of skin color can be achieved by considering both R and M. Therefore, precise skin color match in treating vitiligo or burn patients would be potentially achievable based on extensive collection of skin data from people of Asian descent.
format: application/pdf
format: text/html
creator: Wen-Shyan Huang
creator: Yi-Wen Wang
creator: Kun-Che Hung
creator: Pai-Shan Hsieh
creator: Keng-Yen Fu
creator: Lien-Guo Dai
creator: Nien-Hsien Liou
creator: Kuo-Hsing Ma
creator: Jiang-Chuan Liu
creator: Niann-Tzyy Dai
subject: Bioengineering
subject: Biotechnology
subject: Dermatology
description: doi:10.7717/peerj.4815
publisher: PeerJ Inc.
rights: © 2018 Huang et al.
abstract: Background To treat skin color disorders, such as vitiligo or burns, melanocytes are transplanted for tissue regeneration. However, melanocyte distribution in the human body varies with age and location, making it difficult to select the optimal donor skin to achieve a desired color match. Determining the correlations with the desired skin color measurement based on CIELAB color, epidermal melanocyte numbers, and melanin content of individual melanocytes is critical for clinical application. Method Fifteen foreskin samples from Asian young adults were analyzed for skin color, melanocyte ratio (melanocyte proportion in the epidermis), and melanin concentration. Furthermore, an equation was developed based on CIELAB color with melanocyte ratio, melanin concentration, and the product of melanocyte ratio and melanin concentration. The equation was validated by seeding different ratios of keratinocytes and melanocytes in tissue-engineered skin substitutes, and the degree of fitness in expected skin color was confirmed. Results Linear regression analysis revealed a significant strong negative correlation (r = − 0.847, R2 = 0.717) between CIELAB L* value and the product of the epidermal melanocyte ratio and cell-based melanin concentration. Furthermore, the results showed that an optimal skin color match was achieved by the formula. Discussion We found that L* value was correlated with the value obtained from multiplying the epidermal melanocyte ratio (R) and melanin content (M) and that this correlation was more significant than either L* vs M or L* vs R. This suggests that more accurate prediction of skin color can be achieved by considering both R and M. Therefore, precise skin color match in treating vitiligo or burn patients would be potentially achievable based on extensive collection of skin data from people of Asian descent.
bibliographic citation: Huang et al. (2018) High correlation between skin color based on CIELAB color space, epidermal melanocyte ratio, and melanocyte melanin content. PeerJ 6:e4815 https://doi.org/10.7717/peerj.4815
date submitted: 2018-01-31
date accepted: 2018-05-01
issued: 2018-05-24
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Huang
  given name: Wen-Shyan
author list: Agent
  family name: Wang
  given name: Yi-Wen
author list: Agent
  family name: Hung
  given name: Kun-Che
author list: Agent
  family name: Hsieh
  given name: Pai-Shan
author list: Agent
  family name: Fu
  given name: Keng-Yen
author list: Agent
  family name: Dai
  given name: Lien-Guo
author list: Agent
  family name: Liou
  given name: Nien-Hsien
author list: Agent
  family name: Ma
  given name: Kuo-Hsing
author list: Agent
  family name: Liu
  given name: Jiang-Chuan
author list: Agent
  family name: Dai
  given name: Niann-Tzyy
doi: 10.7717/peerj.4815
volume: 6
issn: 2167-8359
publication name: PeerJ
publication date: 2018-05-24
copyright: ©2018 Huang et al.
attribution name: Huang et al.

Water mites (Acari, Hydrachnidia) of riparian springs in a small lowland river valley: what are the key factors for species distribution?
type: item
type: AcademicArticle
description: This paper examines the impact of disturbance factors—flooding and intermittency—on the distribution of water mites in the riparian springs situated in the valley of a small lowland river, the Krąpiel. The landscape factors and physicochemical parameters of the water were analysed in order to gain an understanding of the pattern of water mite assemblages in the riparian springs. Three limnological types of springs were examined (helocrenes, limnocrenes and rheocrenes) along the whole course of the river and a total of 35 water mite species were found. Our study shows that flooding influences spring assemblages, causing a decrease in crenobiontic water mites in flooded springs. The impact of intermittency resulted in a high percentage of species typical of temporary water bodies. Surprisingly, the study revealed the positive impact of the anthropogenic transformation of the river valley: preventing the riparian springs from flooding enhances the diversity of crenobiontic species in non-flooded springs. In the conclusion, our study revealed that further conservation strategies for the protection of the riparian springs along large rivers would take into account ongoing climatic changes and possible the positive impact of the anthropogenic transformation of river valleys.
format: application/pdf
format: text/html
creator: Andrzej Zawal
creator: Robert Stryjecki
creator: Edyta Buczyńska
creator: Paweł Buczyński
creator: Joanna Pakulnicka
creator: Aleksandra Bańkowska
creator: Tomasz Czernicki
creator: Katarzyna Janusz
creator: Agnieszka Szlauer-Łukaszewska
creator: Vladimir Pešić
subject: Biodiversity
subject: Conservation Biology
subject: Ecology
subject: Zoology
subject: Freshwater Biology
description: doi:10.7717/peerj.4797
publisher: PeerJ Inc.
rights: © 2018 Zawal et al.
abstract: This paper examines the impact of disturbance factors—flooding and intermittency—on the distribution of water mites in the riparian springs situated in the valley of a small lowland river, the Krąpiel. The landscape factors and physicochemical parameters of the water were analysed in order to gain an understanding of the pattern of water mite assemblages in the riparian springs. Three limnological types of springs were examined (helocrenes, limnocrenes and rheocrenes) along the whole course of the river and a total of 35 water mite species were found. Our study shows that flooding influences spring assemblages, causing a decrease in crenobiontic water mites in flooded springs. The impact of intermittency resulted in a high percentage of species typical of temporary water bodies. Surprisingly, the study revealed the positive impact of the anthropogenic transformation of the river valley: preventing the riparian springs from flooding enhances the diversity of crenobiontic species in non-flooded springs. In the conclusion, our study revealed that further conservation strategies for the protection of the riparian springs along large rivers would take into account ongoing climatic changes and possible the positive impact of the anthropogenic transformation of river valleys.
bibliographic citation: Zawal et al. (2018) Water mites (Acari, Hydrachnidia) of riparian springs in a small lowland river valley: what are the key factors for species distribution?. PeerJ 6:e4797 https://doi.org/10.7717/peerj.4797
date submitted: 2018-01-23
date accepted: 2018-04-29
issued: 2018-05-24
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Zawal
  given name: Andrzej
author list: Agent
  family name: Stryjecki
  given name: Robert
author list: Agent
  family name: Buczyńska
  given name: Edyta
author list: Agent
  family name: Buczyński
  given name: Paweł
author list: Agent
  family name: Pakulnicka
  given name: Joanna
author list: Agent
  family name: Bańkowska
  given name: Aleksandra
author list: Agent
  family name: Czernicki
  given name: Tomasz
author list: Agent
  family name: Janusz
  given name: Katarzyna
author list: Agent
  family name: Szlauer-Łukaszewska
  given name: Agnieszka
author list: Agent
  family name: Pešić
  given name: Vladimir
doi: 10.7717/peerj.4797
volume: 6
issn: 2167-8359
publication name: PeerJ
publication date: 2018-05-24
copyright: ©2018 Zawal et al.
attribution name: Zawal et al.

The role of gut microbiota in the regulation of standard metabolic rate in female Periplaneta americana
type: item
type: AcademicArticle
description: Insect gut microbiota contribute significantly to host nutritional ecology. Disrupting insect gut microbial assemblages impacts nutrient provisioning functions, and can potentially affect host standard metabolic rate (SMR), a measure of host energy balance. In this study, we evaluated the effect of disrupting gut microbial assemblages on the SMR of female Periplaneta americana cockroaches fed dog food (DF, high protein/carbohydrate (p/c) ratio), and cellulose-amended dog food (CADF, 30% dog food, 70% cellulose, low p/c ratio) diets, supplemented with none, low, or high antibiotic doses. Bacterial loads decreased significantly between diet types (P = 0.04) and across antibiotic doses (P = 0.04). There was a significant diet type x antibiotic dose interaction on SMR of females on both diets (P = 0.05) by the end of the seven-day experimental period. In CADF-fed females, SMR decreased linearly with decreasing bacterial load. However, SMR of DF-fed females on the low dose was significantly higher than those in the control and high dose groups. This is interpreted as a diet-dependent response by low dose DF-fed females to the loss of nutritional services provided by gut bacteria. Severe reductions in bacterial load at high doses reduced SMR of females on both diet types. This study provides insights into the potential role of gut bacteria as modulators of host energy expenditure under varying dietary conditions.
format: application/pdf
format: text/html
creator: Paul A. Ayayee
creator: Andrew Ondrejech
creator: George Keeney
creator: Agustí Muñoz-Garcia
subject: Ecology
subject: Entomology
subject: Microbiology
description: doi:10.7717/peerj.4717
publisher: PeerJ Inc.
rights: © 2018 Ayayee et al.
abstract: Insect gut microbiota contribute significantly to host nutritional ecology. Disrupting insect gut microbial assemblages impacts nutrient provisioning functions, and can potentially affect host standard metabolic rate (SMR), a measure of host energy balance. In this study, we evaluated the effect of disrupting gut microbial assemblages on the SMR of female Periplaneta americana cockroaches fed dog food (DF, high protein/carbohydrate (p/c) ratio), and cellulose-amended dog food (CADF, 30% dog food, 70% cellulose, low p/c ratio) diets, supplemented with none, low, or high antibiotic doses. Bacterial loads decreased significantly between diet types (P = 0.04) and across antibiotic doses (P = 0.04). There was a significant diet type x antibiotic dose interaction on SMR of females on both diets (P = 0.05) by the end of the seven-day experimental period. In CADF-fed females, SMR decreased linearly with decreasing bacterial load. However, SMR of DF-fed females on the low dose was significantly higher than those in the control and high dose groups. This is interpreted as a diet-dependent response by low dose DF-fed females to the loss of nutritional services provided by gut bacteria. Severe reductions in bacterial load at high doses reduced SMR of females on both diet types. This study provides insights into the potential role of gut bacteria as modulators of host energy expenditure under varying dietary conditions.
bibliographic citation: Ayayee et al. (2018) The role of gut microbiota in the regulation of standard metabolic rate in female Periplaneta americana. PeerJ 6:e4717 https://doi.org/10.7717/peerj.4717
date submitted: 2017-11-09
date accepted: 2018-04-13
issued: 2018-05-24
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Ayayee
  given name: Paul A.
author list: Agent
  family name: Ondrejech
  given name: Andrew
author list: Agent
  family name: Keeney
  given name: George
author list: Agent
  family name: Muñoz-Garcia
  given name: Agustí
doi: 10.7717/peerj.4717
volume: 6
issn: 2167-8359
publication name: PeerJ
publication date: 2018-05-24
copyright: © 2018 Ayayee et al.
attribution name: Ayayee et al.

PeerJ
type: Periodical
uri: PeerJ
issn: 2167-8359