PeerJ
type: channel
link: https://peerj.com/articles/
description: Articles published in PeerJ
publisher: PeerJ Inc.
publication name: PeerJ
issn: 2167-8359
items: Using 3D printed eggs to examine the egg-rejection behaviour of wild birds
items: Have the “mega-journals” reached the limits to growth?
items: Earthworm assemblages in different intensity of agricultural uses and their relation to edaphic variables
items: Evolution of heritable behavioural differences in a model of social division of labour
items: Caveolar disruption causes contraction of rat femoral arteries via reduced basal NO release and subsequent closure of BKCa channels
items: Trans-species polymorphism at antimicrobial innate immunity cathelicidin genes of Atlantic cod and related species
items: Causes of mortality across different immigrant groups in Northeastern Italy
items: Sex differences in human gregariousness
items: Identification of miR-194-5p as a potential biomarker for postmenopausal osteoporosis
items: Rapid cessation of acute diarrhea using a novel solution of bioactive polyphenols: a randomized trial in Nicaraguan children

Using 3D printed eggs to examine the egg-rejection behaviour of wild birds
type: item
type: AcademicArticle
description: The coevolutionary relationships between brood parasites and their hosts are often studied by examining the egg rejection behaviour of host species using artificial eggs. However, the traditional methods for producing artificial eggs out of plasticine, plastic, wood, or plaster-of-Paris are laborious, imprecise, and prone to human error. As an alternative, 3D printing may reduce human error, enable more precise manipulation of egg size and shape, and provide a more accurate and replicable protocol for generating artificial stimuli than traditional methods. However, the usefulness of 3D printing technology for egg rejection research remains to be tested. Here, we applied 3D printing technology to the extensively studied egg rejection behaviour of American robins, Turdus migratorius. Eggs of the robin’s brood parasites, brown-headed cowbirds, Molothrus ater, vary greatly in size and shape, but it is unknown whether host egg rejection decisions differ across this gradient of natural variation. We printed artificial eggs that encompass the natural range of shapes and sizes of cowbird eggs, painted them to resemble either robin or cowbird egg colour, and used them to artificially parasitize nests of breeding wild robins. In line with previous studies, we show that robins accept mimetically coloured and reject non-mimetically coloured artificial eggs. Although we found no evidence that subtle differences in parasitic egg size or shape affect robins’ rejection decisions, 3D printing will provide an opportunity for more extensive experimentation on the potential biological or evolutionary significance of size and shape variation of foreign eggs in rejection decisions. We provide a detailed protocol for generating 3D printed eggs using either personal 3D printers or commercial printing services, and highlight additional potential future applications for this technology in the study of egg rejection.
format: application/pdf
format: text/html
creator: Branislav Igic
creator: Valerie Nunez
creator: Henning U. Voss
creator: Rebecca Croston
creator: Zachary Aidala
creator: Analía V. López
creator: Aimee Van Tatenhove
creator: Mandë E. Holford
creator: Matthew D. Shawkey
creator: Mark E. Hauber
subject: Animal Behavior
subject: Ecology
subject: Zoology
description: doi:10.7717/peerj.965
publisher: PeerJ Inc.
rights: © 2015 Igic et al.
abstract: The coevolutionary relationships between brood parasites and their hosts are often studied by examining the egg rejection behaviour of host species using artificial eggs. However, the traditional methods for producing artificial eggs out of plasticine, plastic, wood, or plaster-of-Paris are laborious, imprecise, and prone to human error. As an alternative, 3D printing may reduce human error, enable more precise manipulation of egg size and shape, and provide a more accurate and replicable protocol for generating artificial stimuli than traditional methods. However, the usefulness of 3D printing technology for egg rejection research remains to be tested. Here, we applied 3D printing technology to the extensively studied egg rejection behaviour of American robins, Turdus migratorius. Eggs of the robin’s brood parasites, brown-headed cowbirds, Molothrus ater, vary greatly in size and shape, but it is unknown whether host egg rejection decisions differ across this gradient of natural variation. We printed artificial eggs that encompass the natural range of shapes and sizes of cowbird eggs, painted them to resemble either robin or cowbird egg colour, and used them to artificially parasitize nests of breeding wild robins. In line with previous studies, we show that robins accept mimetically coloured and reject non-mimetically coloured artificial eggs. Although we found no evidence that subtle differences in parasitic egg size or shape affect robins’ rejection decisions, 3D printing will provide an opportunity for more extensive experimentation on the potential biological or evolutionary significance of size and shape variation of foreign eggs in rejection decisions. We provide a detailed protocol for generating 3D printed eggs using either personal 3D printers or commercial printing services, and highlight additional potential future applications for this technology in the study of egg rejection.
bibliographic citation: Igic et al. (2015) Using 3D printed eggs to examine the egg-rejection behaviour of wild birds. PeerJ 3:e965 https://doi.org/10.7717/peerj.965
date submitted: 2015-03-28
date accepted: 2015-04-29
issued: 2015-05-26
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Igic
  given name: Branislav
author list: Agent
  family name: Nunez
  given name: Valerie
author list: Agent
  family name: Voss
  given name: Henning U.
author list: Agent
  family name: Croston
  given name: Rebecca
author list: Agent
  family name: Aidala
  given name: Zachary
author list: Agent
  family name: López
  given name: Analía V.
author list: Agent
  family name: Van Tatenhove
  given name: Aimee
author list: Agent
  family name: Holford
  given name: Mandë E.
author list: Agent
  family name: Shawkey
  given name: Matthew D.
author list: Agent
  family name: Hauber
  given name: Mark E.
doi: 10.7717/peerj.965
volume: 3
issn: 2167-8359
publication name: PeerJ
publication date: 2015-05-26
copyright: © 2015 Igic et al.
attribution name: Igic et al.

Have the “mega-journals” reached the limits to growth?
type: item
type: AcademicArticle
description: A “mega-journal” is a new type of scientific journal that publishes freely accessible articles, which have been peer reviewed for scientific trustworthiness, but leaves it to the readers to decide which articles are of interest and importance to them. In the wake of the phenomenal success of PLOS ONE, several other publishers have recently started mega-journals. This article presents the evolution of mega-journals since 2010 in terms of article publication rates. The fastest growth seems to have ebbed out at around 35,000 annual articles for the 14 journals combined. Acceptance rates are in the range of 50–70%, and speed of publication is around 3–5 months. Common features in mega-journals are alternative impact metrics, easy reusability of figures and data, post-publication discussions and portable reviews from other journals.
format: application/pdf
format: text/html
creator: Bo-Christer Björk
subject: Science and Medical Education
subject: Science Policy
description: doi:10.7717/peerj.981
publisher: PeerJ Inc.
rights: © 2015 Björk
abstract: A “mega-journal” is a new type of scientific journal that publishes freely accessible articles, which have been peer reviewed for scientific trustworthiness, but leaves it to the readers to decide which articles are of interest and importance to them. In the wake of the phenomenal success of PLOS ONE, several other publishers have recently started mega-journals. This article presents the evolution of mega-journals since 2010 in terms of article publication rates. The fastest growth seems to have ebbed out at around 35,000 annual articles for the 14 journals combined. Acceptance rates are in the range of 50–70%, and speed of publication is around 3–5 months. Common features in mega-journals are alternative impact metrics, easy reusability of figures and data, post-publication discussions and portable reviews from other journals.
bibliographic citation: Björk (2015) Have the “mega-journals” reached the limits to growth?. PeerJ 3:e981 https://doi.org/10.7717/peerj.981
date submitted: 2015-04-07
date accepted: 2015-05-07
issued: 2015-05-26
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Björk
  given name: Bo-Christer
doi: 10.7717/peerj.981
volume: 3
issn: 2167-8359
publication name: PeerJ
publication date: 2015-05-26
copyright: © 2015 Björk
attribution name: Björk

Earthworm assemblages in different intensity of agricultural uses and their relation to edaphic variables
type: item
type: AcademicArticle
description: The objective of this study was to relate earthworm assemblage structure with three different soil use intensities, and to indentify the physical, chemical, and microbiological soil variables that are associated to the observed differences. Three soil uses were evaluated: 1-Fifty year old naturalized grasslands, low use intensity; 2-Recent agricultural fields, intermediate use intensity, and 3-Fifty year old intensive agricultural fields, high use intensity. Three different sites for each soil use were evaluated from winter 2008 through summer 2011. Nine earthworm species were identified across all sampling sites. The sites shared five species: the native Microscolex dubius, and the introduced Aporrectodea caliginosa, A. rosea, Octalasion cyaneum, and O. lacteum, but they differed in relative abundance by soil use. The results show that the earthworm community structure is linked to and modulated by soil properties. Both species abundance and diversity showed significant differences depending on soil use intensity. A principal component analysis showed that species composition is closely related to the environmental variability. The ratio of native to exotic species was significantly lower in the intensive agricultural system when compared to the other two, lower disturbance systems. Microscolex dubius abundance was related to naturalized grasslands along with soil Ca, pH, mechanical resistance, and microbial respiration. Aporrectodea caliginosa abundance was related to high K levels, low enzymatic activity, slightly low pH, low Ca, and appeared related to the highly disturbed environment. Eukerria stagnalis and Aporrectodea rosea, commonly found in the recent agricultural system, were related to high soil moisture condition, low pH, low Ca and low enzymatic activity. These results show that earthworm assemblages can be good indicators of soil use intensities. In particular, Microscolex dubius, Aporrectodea caliginosa, and Aporrectodea rosea, showed different tempor…
format: application/pdf
format: text/html
creator: LB Falco
creator: R Sandler
creator: F Momo
creator: C Di Ciocco
creator: L Saravia
creator: C Coviella
subject: Agricultural Science
subject: Biosphere Interactions
subject: Ecology
subject: Ecosystem Science
subject: Environmental Sciences
description: doi:10.7717/peerj.979
publisher: PeerJ Inc.
rights: © 2015 Falco et al.
abstract: The objective of this study was to relate earthworm assemblage structure with three different soil use intensities, and to indentify the physical, chemical, and microbiological soil variables that are associated to the observed differences. Three soil uses were evaluated: 1-Fifty year old naturalized grasslands, low use intensity; 2-Recent agricultural fields, intermediate use intensity, and 3-Fifty year old intensive agricultural fields, high use intensity. Three different sites for each soil use were evaluated from winter 2008 through summer 2011. Nine earthworm species were identified across all sampling sites. The sites shared five species: the native Microscolex dubius, and the introduced Aporrectodea caliginosa, A. rosea, Octalasion cyaneum, and O. lacteum, but they differed in relative abundance by soil use. The results show that the earthworm community structure is linked to and modulated by soil properties. Both species abundance and diversity showed significant differences depending on soil use intensity. A principal component analysis showed that species composition is closely related to the environmental variability. The ratio of native to exotic species was significantly lower in the intensive agricultural system when compared to the other two, lower disturbance systems. Microscolex dubius abundance was related to naturalized grasslands along with soil Ca, pH, mechanical resistance, and microbial respiration. Aporrectodea caliginosa abundance was related to high K levels, low enzymatic activity, slightly low pH, low Ca, and appeared related to the highly disturbed environment. Eukerria stagnalis and Aporrectodea rosea, commonly found in the recent agricultural system, were related to high soil moisture condition, low pH, low Ca and low enzymatic activity. These results show that earthworm assemblages can be good indicators of soil use intensities. In particular, Microscolex dubius, Aporrectodea caliginosa, and Aporrectodea rosea, showed different tempor…
bibliographic citation: Falco et al. (2015) Earthworm assemblages in different intensity of agricultural uses and their relation to edaphic variables. PeerJ 3:e979 https://doi.org/10.7717/peerj.979
date submitted: 2014-12-19
date accepted: 2015-05-06
issued: 2015-05-26
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Falco
  given name: LB
author list: Agent
  family name: Sandler
  given name: R
author list: Agent
  family name: Momo
  given name: F
author list: Agent
  family name: Di Ciocco
  given name: C
author list: Agent
  family name: Saravia
  given name: L
author list: Agent
  family name: Coviella
  given name: C
doi: 10.7717/peerj.979
volume: 3
issn: 2167-8359
publication name: PeerJ
publication date: 2015-05-26
copyright: © 2015 Falco et al.
attribution name: Falco et al.

Evolution of heritable behavioural differences in a model of social division of labour
type: item
type: AcademicArticle
description: The spectacular diversity of personality and behaviour of animals and humans has evoked many hypotheses intended to explain its developmental and evolutionary background. Although the list of the possible contributing mechanisms seems long, we propose that an underemphasised explanation is the division of labour creating negative frequency dependent selection. We use analytical and numerical models of social division of labour to show how selection can create consistent and heritable behavioural differences in a population, where randomly sampled individuals solve a collective task together. We assume that the collective task needs collaboration of individuals performing one of the two possible subtasks. The total benefit of the group is highest when the ratio of different subtasks is closest to 1. The probability of choosing one of the two costly subtasks and the costs assigned to them are under selection. By using adaptive dynamics we show that if a trade-off between the costs of the subtasks is strong enough, then evolution leads to coexistence of specialized individuals performing one of the subtasks with high probability and low cost. Our analytical results were verified and extended by numerical simulations.
format: application/pdf
format: text/html
creator: Zsóka Vásárhelyi
creator: Géza Meszéna
creator: István Scheuring
subject: Computational Biology
subject: Evolutionary Studies
subject: Mathematical Biology
description: doi:10.7717/peerj.977
publisher: PeerJ Inc.
rights: © 2015 Vásárhelyi et al.
abstract: The spectacular diversity of personality and behaviour of animals and humans has evoked many hypotheses intended to explain its developmental and evolutionary background. Although the list of the possible contributing mechanisms seems long, we propose that an underemphasised explanation is the division of labour creating negative frequency dependent selection. We use analytical and numerical models of social division of labour to show how selection can create consistent and heritable behavioural differences in a population, where randomly sampled individuals solve a collective task together. We assume that the collective task needs collaboration of individuals performing one of the two possible subtasks. The total benefit of the group is highest when the ratio of different subtasks is closest to 1. The probability of choosing one of the two costly subtasks and the costs assigned to them are under selection. By using adaptive dynamics we show that if a trade-off between the costs of the subtasks is strong enough, then evolution leads to coexistence of specialized individuals performing one of the subtasks with high probability and low cost. Our analytical results were verified and extended by numerical simulations.
bibliographic citation: Vásárhelyi et al. (2015) Evolution of heritable behavioural differences in a model of social division of labour. PeerJ 3:e977 https://doi.org/10.7717/peerj.977
date submitted: 2015-03-23
date accepted: 2015-05-06
issued: 2015-05-26
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Vásárhelyi
  given name: Zsóka
author list: Agent
  family name: Meszéna
  given name: Géza
author list: Agent
  family name: Scheuring
  given name: István
doi: 10.7717/peerj.977
volume: 3
issn: 2167-8359
publication name: PeerJ
publication date: 2015-05-26
copyright: © 2015 Vásárhelyi et al.
attribution name: Vásárhelyi et al.

Caveolar disruption causes contraction of rat femoral arteries via reduced basal NO release and subsequent closure of BKCa channels
type: item
type: AcademicArticle
description: Background and Purpose. Caveolae act as signalling hubs in endothelial and smooth muscle cells. Caveolar disruption by the membrane cholesterol depleting agent methyl-β-cyclodextrin (M-β-CD) has various functional effects on arteries including (i) impairment of endothelium-dependent relaxation, and (ii) alteration of smooth muscle cell (SMC) contraction independently of the endothelium. The aim of this study was to explore the effects of M-β-CD on rat femoral arteries. Methods. Isometric force was measured in rat femoral arteries stimulated to contract with a solution containing 20 mM K+ and 200 nM Bay K 8644 (20 K/Bay K) or with one containing 80 mM K+(80 K). Results. Incubation of arteries with M-β-CD (5 mM, 60 min) increased force in response to 20 K/Bay K but not that induced by 80 K. Application of cholesterol saturated M-β-CD (Ch-MCD, 5 mM, 50 min) reversed the effects of M-β-CD. After mechanical removal of endothelial cells M-β-CD caused only a small enhancement of contractions to 20 K/Bay K. This result suggests M-β-CD acts via altering release of an endothelial-derived vasodilator or vasoconstrictor. When nitric oxide synthase was blocked by pre-incubation of arteries with L-NAME (250 µM) the contraction of arteries to 20 K/Bay K was enhanced, and this effect was abolished by pre-treatment with M-β-CD. This suggests M-β-CD is inhibiting endothelial NO release. Inhibition of large conductance voltage- and Ca2+-activated (BKCa) channels with 2 mM TEA+ or 100 nM Iberiotoxin (IbTX) enhanced 20 K/Bay K contractions. L-NAME attenuated the contractile effect of IbTX, as did endothelial removal. Conclusions. Our results suggest caveolar disruption results in decreased release of endothelial-derived nitric oxide in rat femoral artery, resulting in a reduced contribution of BKCa channels to the smooth muscle cell membrane potential, causing depolarisation and contraction.
format: application/pdf
format: text/html
creator: AY Al-Brakati
creator: T Kamishima
creator: C Dart
creator: JM Quayle
subject: Anatomy and Physiology
subject: Cardiology
description: doi:10.7717/peerj.966
publisher: PeerJ Inc.
rights: © 2015 Al-Brakati et al.
abstract: Background and Purpose. Caveolae act as signalling hubs in endothelial and smooth muscle cells. Caveolar disruption by the membrane cholesterol depleting agent methyl-β-cyclodextrin (M-β-CD) has various functional effects on arteries including (i) impairment of endothelium-dependent relaxation, and (ii) alteration of smooth muscle cell (SMC) contraction independently of the endothelium. The aim of this study was to explore the effects of M-β-CD on rat femoral arteries. Methods. Isometric force was measured in rat femoral arteries stimulated to contract with a solution containing 20 mM K+ and 200 nM Bay K 8644 (20 K/Bay K) or with one containing 80 mM K+(80 K). Results. Incubation of arteries with M-β-CD (5 mM, 60 min) increased force in response to 20 K/Bay K but not that induced by 80 K. Application of cholesterol saturated M-β-CD (Ch-MCD, 5 mM, 50 min) reversed the effects of M-β-CD. After mechanical removal of endothelial cells M-β-CD caused only a small enhancement of contractions to 20 K/Bay K. This result suggests M-β-CD acts via altering release of an endothelial-derived vasodilator or vasoconstrictor. When nitric oxide synthase was blocked by pre-incubation of arteries with L-NAME (250 µM) the contraction of arteries to 20 K/Bay K was enhanced, and this effect was abolished by pre-treatment with M-β-CD. This suggests M-β-CD is inhibiting endothelial NO release. Inhibition of large conductance voltage- and Ca2+-activated (BKCa) channels with 2 mM TEA+ or 100 nM Iberiotoxin (IbTX) enhanced 20 K/Bay K contractions. L-NAME attenuated the contractile effect of IbTX, as did endothelial removal. Conclusions. Our results suggest caveolar disruption results in decreased release of endothelial-derived nitric oxide in rat femoral artery, resulting in a reduced contribution of BKCa channels to the smooth muscle cell membrane potential, causing depolarisation and contraction.
bibliographic citation: Al-Brakati et al. (2015) Caveolar disruption causes contraction of rat femoral arteries via reduced basal NO release and subsequent closure of BKCa channels. PeerJ 3:e966 https://doi.org/10.7717/peerj.966
date submitted: 2015-02-10
date accepted: 2015-04-29
issued: 2015-05-26
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Al-Brakati
  given name: AY
author list: Agent
  family name: Kamishima
  given name: T
author list: Agent
  family name: Dart
  given name: C
author list: Agent
  family name: Quayle
  given name: JM
doi: 10.7717/peerj.966
volume: 3
issn: 2167-8359
publication name: PeerJ
publication date: 2015-05-26
copyright: © 2015 Al-Brakati et al.
attribution name: Al-Brakati et al.

Trans-species polymorphism at antimicrobial innate immunity cathelicidin genes of Atlantic cod and related species
type: item
type: AcademicArticle
description: Natural selection, the most important force in evolution, comes in three forms. Negative purifying selection removes deleterious variation and maintains adaptations. Positive directional selection fixes beneficial variants, producing new adaptations. Balancing selection maintains variation in a population. Important mechanisms of balancing selection include heterozygote advantage, frequency-dependent advantage of rarity, and local and fluctuating episodic selection. A rare pathogen gains an advantage because host defenses are predominantly effective against prevalent types. Similarly, a rare immune variant gives its host an advantage because the prevalent pathogens cannot escape the host’s apostatic defense. Due to the stochastic nature of evolution, neutral variation may accumulate on genealogical branches, but trans-species polymorphisms are rare under neutrality and are strong evidence for balancing selection. Balanced polymorphism maintains diversity at the major histocompatibility complex (MHC) in vertebrates. The Atlantic cod is missing genes for both MHC-II and CD4, vital parts of the adaptive immune system. Nevertheless, cod are healthy in their ecological niche, maintaining large populations that support major commercial fisheries. Innate immunity is of interest from an evolutionary perspective, particularly in taxa lacking adaptive immunity. Here, we analyze extensive amino acid and nucleotide polymorphisms of the cathelicidin gene family in Atlantic cod and closely related taxa. There are three major clusters, Cath1, Cath2, and Cath3, that we consider to be paralogous genes. There is extensive nucleotide and amino acid allelic variation between and within clusters. The major feature of the results is that the variation clusters by alleles and not by species in phylogenetic trees and discriminant analysis of principal components. Variation within the three groups shows trans-species polymorphism that is older than speciation and that is suggestive of balan…
format: application/pdf
format: text/html
creator: Katrín Halldórsdóttir
creator: Einar Árnason
subject: Aquaculture, Fisheries and Fish Science
subject: Evolutionary Studies
subject: Genetics
subject: Marine Biology
subject: Immunology
description: doi:10.7717/peerj.976
publisher: PeerJ Inc.
rights: © 2015 Halldórsdóttir and Árnason
abstract: Natural selection, the most important force in evolution, comes in three forms. Negative purifying selection removes deleterious variation and maintains adaptations. Positive directional selection fixes beneficial variants, producing new adaptations. Balancing selection maintains variation in a population. Important mechanisms of balancing selection include heterozygote advantage, frequency-dependent advantage of rarity, and local and fluctuating episodic selection. A rare pathogen gains an advantage because host defenses are predominantly effective against prevalent types. Similarly, a rare immune variant gives its host an advantage because the prevalent pathogens cannot escape the host’s apostatic defense. Due to the stochastic nature of evolution, neutral variation may accumulate on genealogical branches, but trans-species polymorphisms are rare under neutrality and are strong evidence for balancing selection. Balanced polymorphism maintains diversity at the major histocompatibility complex (MHC) in vertebrates. The Atlantic cod is missing genes for both MHC-II and CD4, vital parts of the adaptive immune system. Nevertheless, cod are healthy in their ecological niche, maintaining large populations that support major commercial fisheries. Innate immunity is of interest from an evolutionary perspective, particularly in taxa lacking adaptive immunity. Here, we analyze extensive amino acid and nucleotide polymorphisms of the cathelicidin gene family in Atlantic cod and closely related taxa. There are three major clusters, Cath1, Cath2, and Cath3, that we consider to be paralogous genes. There is extensive nucleotide and amino acid allelic variation between and within clusters. The major feature of the results is that the variation clusters by alleles and not by species in phylogenetic trees and discriminant analysis of principal components. Variation within the three groups shows trans-species polymorphism that is older than speciation and that is suggestive of balan…
bibliographic citation: Halldórsdóttir et al. (2015) Trans-species polymorphism at antimicrobial innate immunity cathelicidin genes of Atlantic cod and related species. PeerJ 3:e976 https://doi.org/10.7717/peerj.976
date submitted: 2015-03-24
date accepted: 2015-05-05
issued: 2015-05-21
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Halldórsdóttir
  given name: Katrín
author list: Agent
  family name: Árnason
  given name: Einar
doi: 10.7717/peerj.976
volume: 3
issn: 2167-8359
publication name: PeerJ
publication date: 2015-05-21
copyright: © 2015 Halldórsdóttir and Árnason
attribution name: Halldórsdóttir and Árnason

Causes of mortality across different immigrant groups in Northeastern Italy
type: item
type: AcademicArticle
description: Background. Despite massive immigration towards Southern Europe in the last two decades, data on mortality by cause among immigrants in Italy are scarce. The aim of this study was to investigate mortality from all and from specific causes of death among immigrants residing in the Veneto Region (Northeastern Italy). Methods. Mortality records for the period 2008–2013 were extracted from the regional archive of causes of death, whereas population data were obtained from the 2011 Italian census. Immigrants were grouped by area of provenience based on the information on country of citizenship available both in mortality and census data. Standardized Mortality Ratios (SMR) with 95% Confidence Intervals (CI) were computed for the period 2008–2013 in subjects aged 20–59 years, with rates of Italian citizens as a reference. Results. Overall mortality was reduced both in male (SMR 0.86, CI [0.80–0.92]) and female immigrants (SMR 0.72, CI [0.65–0.78]), although an increased risk was observed for subjects from Sub-Saharan Africa. Significantly raised SMR for circulatory diseases were found among Sub-Saharan Africans and Southern Asians in both genders. Sub-Saharan Africans experienced a higher risk of death, especially from cerebrovascular diseases: SMR 4.78 (CI [2.67–7.89]) and SMR 6.09 (CI [1.96–14.2]) in males and females, respectively. Among Southern Asians, the increase in mortality from ischemic heart diseases reached statistical significance in males (SMR 2.53, CI [1.42–4.18]). In spite of a lower risk of death for all neoplasms combined, mortality from cancer of cervix uteri was increased among immigrants (SMR 2.61, CI [1.35–4.56]), as well as for other cancer sites in selected immigrant groups. A raised mortality was found for infectious diseases in Sub-Saharan Africans (both genders), and for transport accidents among females from Eastern Europe. Conclusion. Our study showed great variations in mortality by cause and area of provenience among immigrants resident in t…
format: application/pdf
format: text/html
creator: Ugo Fedeli
creator: Eliana Ferroni
creator: Mara Pigato
creator: Francesco Avossa
creator: Mario Saugo
subject: Epidemiology
description: doi:10.7717/peerj.975
publisher: PeerJ Inc.
rights: © 2015 Fedeli et al.
abstract: Background. Despite massive immigration towards Southern Europe in the last two decades, data on mortality by cause among immigrants in Italy are scarce. The aim of this study was to investigate mortality from all and from specific causes of death among immigrants residing in the Veneto Region (Northeastern Italy). Methods. Mortality records for the period 2008–2013 were extracted from the regional archive of causes of death, whereas population data were obtained from the 2011 Italian census. Immigrants were grouped by area of provenience based on the information on country of citizenship available both in mortality and census data. Standardized Mortality Ratios (SMR) with 95% Confidence Intervals (CI) were computed for the period 2008–2013 in subjects aged 20–59 years, with rates of Italian citizens as a reference. Results. Overall mortality was reduced both in male (SMR 0.86, CI [0.80–0.92]) and female immigrants (SMR 0.72, CI [0.65–0.78]), although an increased risk was observed for subjects from Sub-Saharan Africa. Significantly raised SMR for circulatory diseases were found among Sub-Saharan Africans and Southern Asians in both genders. Sub-Saharan Africans experienced a higher risk of death, especially from cerebrovascular diseases: SMR 4.78 (CI [2.67–7.89]) and SMR 6.09 (CI [1.96–14.2]) in males and females, respectively. Among Southern Asians, the increase in mortality from ischemic heart diseases reached statistical significance in males (SMR 2.53, CI [1.42–4.18]). In spite of a lower risk of death for all neoplasms combined, mortality from cancer of cervix uteri was increased among immigrants (SMR 2.61, CI [1.35–4.56]), as well as for other cancer sites in selected immigrant groups. A raised mortality was found for infectious diseases in Sub-Saharan Africans (both genders), and for transport accidents among females from Eastern Europe. Conclusion. Our study showed great variations in mortality by cause and area of provenience among immigrants resident in t…
bibliographic citation: Fedeli et al. (2015) Causes of mortality across different immigrant groups in Northeastern Italy. PeerJ 3:e975 https://doi.org/10.7717/peerj.975
date submitted: 2015-03-26
date accepted: 2015-05-05
issued: 2015-05-21
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Fedeli
  given name: Ugo
author list: Agent
  family name: Ferroni
  given name: Eliana
author list: Agent
  family name: Pigato
  given name: Mara
author list: Agent
  family name: Avossa
  given name: Francesco
author list: Agent
  family name: Saugo
  given name: Mario
doi: 10.7717/peerj.975
volume: 3
issn: 2167-8359
publication name: PeerJ
publication date: 2015-05-21
copyright: © 2015 Fedeli et al.
attribution name: Fedeli et al.

Sex differences in human gregariousness
type: item
type: AcademicArticle
description: Research on human sociality rarely includes kinship, social structure, sex, and familiarity, even though these variables influence sociality in non-human primates. However, cross-cultural ethnographic and observational studies with humans indicate that, beginning after age 5 years, males and females form differing social structures with unrelated individuals in a community. Specifically, compared with females, human males exhibit greater tolerance for and form larger, interconnected groups of peers which we term “gregariousness.” To examine sex differences in gregariousness early in life when children first interact with peers without adult supervision, 3- to 6-year-old children were given the choice to enter one of three play areas: an empty one, one with an adult, or one with a familiar, same-sex peer. More males than females initially chose the play area with the same-sex peer, especially after age 5 years. Sex differences in gregariousness with same-sex peers likely constitute one facet of human sociality.
format: application/pdf
format: text/html
creator: Joyce F. Benenson
creator: Sandra Stella
creator: Anthony Ferranti
subject: Anthropology
description: doi:10.7717/peerj.974
publisher: PeerJ Inc.
rights: © 2015 Benenson et al.
abstract: Research on human sociality rarely includes kinship, social structure, sex, and familiarity, even though these variables influence sociality in non-human primates. However, cross-cultural ethnographic and observational studies with humans indicate that, beginning after age 5 years, males and females form differing social structures with unrelated individuals in a community. Specifically, compared with females, human males exhibit greater tolerance for and form larger, interconnected groups of peers which we term “gregariousness.” To examine sex differences in gregariousness early in life when children first interact with peers without adult supervision, 3- to 6-year-old children were given the choice to enter one of three play areas: an empty one, one with an adult, or one with a familiar, same-sex peer. More males than females initially chose the play area with the same-sex peer, especially after age 5 years. Sex differences in gregariousness with same-sex peers likely constitute one facet of human sociality.
bibliographic citation: Benenson et al. (2015) Sex differences in human gregariousness. PeerJ 3:e974 https://doi.org/10.7717/peerj.974
date submitted: 2015-02-18
date accepted: 2015-05-04
issued: 2015-05-21
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Benenson
  given name: Joyce F.
author list: Agent
  family name: Stella
  given name: Sandra
author list: Agent
  family name: Ferranti
  given name: Anthony
doi: 10.7717/peerj.974
volume: 3
issn: 2167-8359
publication name: PeerJ
publication date: 2015-05-21
copyright: © 2015 Benenson et al.
attribution name: Benenson et al.

Identification of miR-194-5p as a potential biomarker for postmenopausal osteoporosis
type: item
type: AcademicArticle
description: The incidence of osteoporosis is high in postmenopausal women due to altered estrogen levels and continuous calcium loss that occurs with aging. Recent studies have shown that microRNAs (miRNAs) are involved in the development of osteoporosis. These miRNAs may be used as potential biomarkers to identify women at a high risk for developing the disease. In this study, whole blood samples were collected from 48 postmenopausal Chinese women with osteopenia or osteoporosis and pooled into six groups according to individual T-scores. A miRNA microarray analysis was performed on pooled blood samples to identify potential miRNA biomarkers for postmenopausal osteoporosis. Five miRNAs (miR-130b-3p, -151a-3p, -151b, -194-5p, and -590-5p) were identified in the microarray analysis. These dysregulated miRNAs were subjected to a pathway analysis investigating whether they were involved in regulating osteoporosis-related pathways. Among them, only miR-194-5p was enriched in multiple osteoporosis-related pathways. Enhanced miR-194-5p expression in women with osteoporosis was confirmed by quantitative reverse transcription–polymerase chain reaction analysis. For external validation, a significant correlation between the expression of miR-194-5p and T-scores was found in an independent patient collection comprised of 24 postmenopausal women with normal bone mineral density, 30 postmenopausal women with osteopenia, and 32 postmenopausal women with osteoporosis (p < 0.05). Taken together, the present findings suggest that miR-194-5p may be a viable miRNA biomarker for postmenopausal osteoporosis.
format: application/pdf
format: text/html
creator: Jia Meng
creator: Dapeng Zhang
creator: Nanan Pan
creator: Ning Sun
creator: Qiujun Wang
creator: Jingxue Fan
creator: Ping Zhou
creator: Wenliang Zhu
creator: Lihong Jiang
subject: Molecular Biology
subject: Geriatrics
description: doi:10.7717/peerj.971
publisher: PeerJ Inc.
rights: © 2015 Meng et al.
abstract: The incidence of osteoporosis is high in postmenopausal women due to altered estrogen levels and continuous calcium loss that occurs with aging. Recent studies have shown that microRNAs (miRNAs) are involved in the development of osteoporosis. These miRNAs may be used as potential biomarkers to identify women at a high risk for developing the disease. In this study, whole blood samples were collected from 48 postmenopausal Chinese women with osteopenia or osteoporosis and pooled into six groups according to individual T-scores. A miRNA microarray analysis was performed on pooled blood samples to identify potential miRNA biomarkers for postmenopausal osteoporosis. Five miRNAs (miR-130b-3p, -151a-3p, -151b, -194-5p, and -590-5p) were identified in the microarray analysis. These dysregulated miRNAs were subjected to a pathway analysis investigating whether they were involved in regulating osteoporosis-related pathways. Among them, only miR-194-5p was enriched in multiple osteoporosis-related pathways. Enhanced miR-194-5p expression in women with osteoporosis was confirmed by quantitative reverse transcription–polymerase chain reaction analysis. For external validation, a significant correlation between the expression of miR-194-5p and T-scores was found in an independent patient collection comprised of 24 postmenopausal women with normal bone mineral density, 30 postmenopausal women with osteopenia, and 32 postmenopausal women with osteoporosis (p < 0.05). Taken together, the present findings suggest that miR-194-5p may be a viable miRNA biomarker for postmenopausal osteoporosis.
bibliographic citation: Meng et al. (2015) Identification of miR-194-5p as a potential biomarker for postmenopausal osteoporosis. PeerJ 3:e971 https://doi.org/10.7717/peerj.971
date submitted: 2014-12-27
date accepted: 2015-05-02
issued: 2015-05-21
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Meng
  given name: Jia
author list: Agent
  family name: Zhang
  given name: Dapeng
author list: Agent
  family name: Pan
  given name: Nanan
author list: Agent
  family name: Sun
  given name: Ning
author list: Agent
  family name: Wang
  given name: Qiujun
author list: Agent
  family name: Fan
  given name: Jingxue
author list: Agent
  family name: Zhou
  given name: Ping
author list: Agent
  family name: Zhu
  given name: Wenliang
author list: Agent
  family name: Jiang
  given name: Lihong
doi: 10.7717/peerj.971
volume: 3
issn: 2167-8359
publication name: PeerJ
publication date: 2015-05-21
copyright: © 2015 Meng et al.
attribution name: Meng et al.

Rapid cessation of acute diarrhea using a novel solution of bioactive polyphenols: a randomized trial in Nicaraguan children
type: item
type: AcademicArticle
description: Goal. We assessed the effectiveness of bioactive polyphenols contained in solution (LX) to restore normal bowel function in pediatric patients with acute diarrhea. Background. While providing oral rehydration solution (ORS) is standard treatment for diarrhea in developing countries, plant-derived products have been shown to positively affect intestinal function. If a supplement to ORS resolves diarrhea more rapidly than ORS alone, it is an improvement to current care. Study. In a randomized, double-blind, placebo-controlled cross-over study, 61 pediatric patients with uncontrolled diarrhea were randomized to receive either ORS + LX on day 1 and then ORS + water on day 2 (study arm) or ORS + water on day 1 and then ORS + LX on day 2 (control arm). Time to resolution and number of bowel movements were recorded. Results. On day 1, the mean time to diarrhea resolution was 3.1 h (study arm) versus 9.2 h (control arm) (p = 0.002). In the study arm, 60% of patients had normal stool at their first bowel movement after consumption of the phenolic redoxigen solution (LX). On day 2, patients in the study arm continued to have normal stool while patients in the control arm achieved normal stool within 24 h after consuming the test solution. Patients in the control arm experienced a reduction in the mean number of bowel movements from day 1 to day 2 after consuming the test solution (p = 0.0001). No adverse events were observed. Conclusions. Significant decreases in bowel movement frequency and rapid normalization of stool consistency were observed with consumption of this novel solution.
format: application/pdf
format: text/html
creator: Arthur Dover
creator: Neema Patel
creator: KT Park
subject: Clinical Trials
subject: Gastroenterology and Hepatology
subject: Global Health
description: doi:10.7717/peerj.969
publisher: PeerJ Inc.
rights: © 2015 Dover et al.
abstract: Goal. We assessed the effectiveness of bioactive polyphenols contained in solution (LX) to restore normal bowel function in pediatric patients with acute diarrhea. Background. While providing oral rehydration solution (ORS) is standard treatment for diarrhea in developing countries, plant-derived products have been shown to positively affect intestinal function. If a supplement to ORS resolves diarrhea more rapidly than ORS alone, it is an improvement to current care. Study. In a randomized, double-blind, placebo-controlled cross-over study, 61 pediatric patients with uncontrolled diarrhea were randomized to receive either ORS + LX on day 1 and then ORS + water on day 2 (study arm) or ORS + water on day 1 and then ORS + LX on day 2 (control arm). Time to resolution and number of bowel movements were recorded. Results. On day 1, the mean time to diarrhea resolution was 3.1 h (study arm) versus 9.2 h (control arm) (p = 0.002). In the study arm, 60% of patients had normal stool at their first bowel movement after consumption of the phenolic redoxigen solution (LX). On day 2, patients in the study arm continued to have normal stool while patients in the control arm achieved normal stool within 24 h after consuming the test solution. Patients in the control arm experienced a reduction in the mean number of bowel movements from day 1 to day 2 after consuming the test solution (p = 0.0001). No adverse events were observed. Conclusions. Significant decreases in bowel movement frequency and rapid normalization of stool consistency were observed with consumption of this novel solution.
bibliographic citation: Dover et al. (2015) Rapid cessation of acute diarrhea using a novel solution of bioactive polyphenols: a randomized trial in Nicaraguan children. PeerJ 3:e969 https://doi.org/10.7717/peerj.969
date submitted: 2015-01-23
date accepted: 2015-04-30
issued: 2015-05-21
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Dover
  given name: Arthur
author list: Agent
  family name: Patel
  given name: Neema
author list: Agent
  family name: Park
  given name: KT
doi: 10.7717/peerj.969
volume: 3
issn: 2167-8359
publication name: PeerJ
publication date: 2015-05-21
copyright: © 2015 Dover et al.
attribution name: Dover et al.

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