PeerJ
type: channel
link: https://peerj.com/articles/
description: Articles published in PeerJ
publisher: PeerJ Inc.
publication name: PeerJ
issn: 2167-8359
items: Some like it hot: a differential response to changing temperatures by the malaria vectors Anopheles funestus and An. gambiae s.l.
items: A comparison of least squares regression and geographically weighted regression modeling of West Nile virus risk based on environmental parameters
items: A functional approach to the body condition assessment of lactating donkeys as a tool for welfare evaluation
items: Systematic drug repositioning through mining adverse event data in ClinicalTrials.gov
items: Genetic insights into family group co-occurrence in Cryptocercus punctulatus, a sub-social woodroach from the southern Appalachian Mountains
items: Seed germination in a southern Australian temperate seagrass
items: Basal tolerance to heat and cold exposure of the spotted wing drosophila, Drosophila suzukii
items: Analysis of different vibration patterns to guide blind people
items: Are floating algal mats a refuge from hypoxia for estuarine invertebrates?
items: Climate change promotes hybridisation between deeply divergent species

Some like it hot: a differential response to changing temperatures by the malaria vectors Anopheles funestus and An. gambiae s.l.
type: item
type: AcademicArticle
description: Background With the possible implications of global warming, the effect of temperature on the dynamics of malaria vectors in Africa has become a subject of increasing interest. Information from the field is, however, relatively sparse. We describe the effect of ambient temperature over a five-year period on the dynamics of An. funestus and An. gambiae s.l., collected from a single village in southern Mozambique where temperatures varied from a night-time minimum of 6 °C in the cool season to a daytime maximum of 35 °C in the hot season. Results Mean daily air temperatures varied from 34 °C to 20 °C and soil temperatures varied from 26 °C to 12 °C. Diurnal variation was greatest in the cooler months of the year and were greater in air temperatures than soil temperatures. During the study 301, 705 female An. funestus were collected in 6,043 light-trap collections, 161, 466 in 7,397 exit collections and 16, 995 in 1,315 resting collections. The equivalent numbers for An. gambiae s.l. are 72,475 in light-traps, 33, 868 in exit collections and 5,333 from indoor resting collections. Numbers of mosquito were greatest in the warmer months. Numbers of An. gambiae s.l. went through a one hundredfold change (from a mean of 0.14 mosquitoes a night to 14) whereas numbers of An. funestus merely doubled (from a mean of 20 to 40 a night). The highest environmental correlations and mosquito numbers were between mean air temperature (r2 = 0.52 for An. funestus and 0.77 for An. gambiae s.l.). Numbers of mosquito collected were not related to rainfall with lags of up to four weeks. Numbers of both gravid and unfed An. gambiae complex females in exit collections continued to increase at all temperatures recorded but gravid females of An. funestus decreased at temperatures above 28 °C. Overall the numbers of gravid and unfed An. funestus collected in exit collections were not correlated (p = 0.07). For an unknown reason the number of An. gambiae s.l. fell below monitoring thresholds duri…
format: application/pdf
format: text/html
creator: Jacques Derek Charlwood
subject: Ecology
subject: Entomology
subject: Epidemiology
subject: Global Health
subject: Infectious Diseases
description: doi:10.7717/peerj.3099
publisher: PeerJ Inc.
rights: © 2017 Charlwood
abstract: Background With the possible implications of global warming, the effect of temperature on the dynamics of malaria vectors in Africa has become a subject of increasing interest. Information from the field is, however, relatively sparse. We describe the effect of ambient temperature over a five-year period on the dynamics of An. funestus and An. gambiae s.l., collected from a single village in southern Mozambique where temperatures varied from a night-time minimum of 6 °C in the cool season to a daytime maximum of 35 °C in the hot season. Results Mean daily air temperatures varied from 34 °C to 20 °C and soil temperatures varied from 26 °C to 12 °C. Diurnal variation was greatest in the cooler months of the year and were greater in air temperatures than soil temperatures. During the study 301, 705 female An. funestus were collected in 6,043 light-trap collections, 161, 466 in 7,397 exit collections and 16, 995 in 1,315 resting collections. The equivalent numbers for An. gambiae s.l. are 72,475 in light-traps, 33, 868 in exit collections and 5,333 from indoor resting collections. Numbers of mosquito were greatest in the warmer months. Numbers of An. gambiae s.l. went through a one hundredfold change (from a mean of 0.14 mosquitoes a night to 14) whereas numbers of An. funestus merely doubled (from a mean of 20 to 40 a night). The highest environmental correlations and mosquito numbers were between mean air temperature (r2 = 0.52 for An. funestus and 0.77 for An. gambiae s.l.). Numbers of mosquito collected were not related to rainfall with lags of up to four weeks. Numbers of both gravid and unfed An. gambiae complex females in exit collections continued to increase at all temperatures recorded but gravid females of An. funestus decreased at temperatures above 28 °C. Overall the numbers of gravid and unfed An. funestus collected in exit collections were not correlated (p = 0.07). For an unknown reason the number of An. gambiae s.l. fell below monitoring thresholds duri…
bibliographic citation: Charlwood (2017) Some like it hot: a differential response to changing temperatures by the malaria vectors Anopheles funestus and An. gambiae s.l.. PeerJ 5:e3099 https://doi.org/10.7717/peerj.3099
date submitted: 2016-04-29
date accepted: 2017-02-16
issued: 2017-03-28
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Charlwood
  given name: Jacques Derek
doi: 10.7717/peerj.3099
volume: 5
issn: 2167-8359
publication name: PeerJ
publication date: 2017-03-28
copyright: ©2017 Charlwood
attribution name: Charlwood

A comparison of least squares regression and geographically weighted regression modeling of West Nile virus risk based on environmental parameters
type: item
type: AcademicArticle
description: Background The primary aim of the study reported here was to determine the effectiveness of utilizing local spatial variations in environmental data to uncover the statistical relationships between West Nile Virus (WNV) risk and environmental factors. Because least squares regression methods do not account for spatial autocorrelation and non-stationarity of the type of spatial data analyzed for studies that explore the relationship between WNV and environmental determinants, we hypothesized that a geographically weighted regression model would help us better understand how environmental factors are related to WNV risk patterns without the confounding effects of spatial non-stationarity. Methods We examined commonly mapped environmental factors using both ordinary least squares regression (LSR) and geographically weighted regression (GWR). Both types of models were applied to examine the relationship between WNV-infected dead bird counts and various environmental factors for those locations. The goal was to determine which approach yielded a better predictive model. Results LSR efforts lead to identifying three environmental variables that were statistically significantly related to WNV infected dead birds (adjusted R2 = 0.61): stream density, road density, and land surface temperature. GWR efforts increased the explanatory value of these three environmental variables with better spatial precision (adjusted R2 = 0.71). Conclusions The spatial granularity resulting from the geographically weighted approach provides a better understanding of how environmental spatial heterogeneity is related to WNV risk as implied by WNV infected dead birds, which should allow improved planning of public health management strategies.
format: application/pdf
format: text/html
creator: Abhishek K. Kala
creator: Chetan Tiwari
creator: Armin R. Mikler
creator: Samuel F. Atkinson
subject: Biogeography
subject: Environmental Sciences
subject: Epidemiology
subject: Infectious Diseases
subject: Public Health
description: doi:10.7717/peerj.3070
publisher: PeerJ Inc.
rights: © 2017 Kala et al.
abstract: Background The primary aim of the study reported here was to determine the effectiveness of utilizing local spatial variations in environmental data to uncover the statistical relationships between West Nile Virus (WNV) risk and environmental factors. Because least squares regression methods do not account for spatial autocorrelation and non-stationarity of the type of spatial data analyzed for studies that explore the relationship between WNV and environmental determinants, we hypothesized that a geographically weighted regression model would help us better understand how environmental factors are related to WNV risk patterns without the confounding effects of spatial non-stationarity. Methods We examined commonly mapped environmental factors using both ordinary least squares regression (LSR) and geographically weighted regression (GWR). Both types of models were applied to examine the relationship between WNV-infected dead bird counts and various environmental factors for those locations. The goal was to determine which approach yielded a better predictive model. Results LSR efforts lead to identifying three environmental variables that were statistically significantly related to WNV infected dead birds (adjusted R2 = 0.61): stream density, road density, and land surface temperature. GWR efforts increased the explanatory value of these three environmental variables with better spatial precision (adjusted R2 = 0.71). Conclusions The spatial granularity resulting from the geographically weighted approach provides a better understanding of how environmental spatial heterogeneity is related to WNV risk as implied by WNV infected dead birds, which should allow improved planning of public health management strategies.
bibliographic citation: Kala et al. (2017) A comparison of least squares regression and geographically weighted regression modeling of West Nile virus risk based on environmental parameters. PeerJ 5:e3070 https://doi.org/10.7717/peerj.3070
date submitted: 2016-09-08
date accepted: 2017-02-07
issued: 2017-03-28
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Kala
  given name: Abhishek K.
author list: Agent
  family name: Tiwari
  given name: Chetan
author list: Agent
  family name: Mikler
  given name: Armin R.
author list: Agent
  family name: Atkinson
  given name: Samuel F.
doi: 10.7717/peerj.3070
volume: 5
issn: 2167-8359
publication name: PeerJ
publication date: 2017-03-28
copyright: ©2017 Kala et al.
attribution name: Kala et al.

A functional approach to the body condition assessment of lactating donkeys as a tool for welfare evaluation
type: item
type: AcademicArticle
description: Background The breeding of lactating donkeys is increasing in Western Europe; with it the evaluation of body condition is growing in importance since it is considered a key principle for their welfare. However, assessment of body condition is a complex task, since several factors are involved. The aim of the present study is to investigate which animal-based indicators are the most reliable to describe the body condition of lactating donkeys. For this purpose, new animal-based indicators, which are easy to measure in field conditions (including body measurements, fatty neck score (FNS), dental score), are recorded and their relationship with BCS (a proxy measure for overall adiposity) was assessed. The ones that reveal an association with the BCS are included in an integrated principal component analysis to understand which are the most related to BCS. Methods Fifty-three healthy lactating donkeys of various breeds, including 7 Martina Franca, 10 Ragusano, 2 Romagnolo and 34 crossbreeds, were evaluated. The animal-based indicators that were recorded were: length (OP, olecranon tuber-pinbone and SH, shoulder-hip), heart girth (HG), abdominal circumference (AC), neck length (NL), neck height (NH) and neck thickness (NT) at 0.50 and neck circumference (NC) at 0.25, 0.50 and 0.75, body condition score (BCS) and fatty neck score (FNS). The owners’ evaluation of the BCS was also considered. A dental assessment was performed and the month of lactation and age of each animal was recorded. Results No correlation was found between BCS and the other morphometric body measurements. On the contrary the FNS was correlated with the morphometric measurements of the neck (positive correlation to 0.50 NH and 0.50 NT, 0.50 NC, 0.75 mean NC, and negative correlation to the mean NC:NH and mean NC:NT, 0.50 NC:NT and 0.50 NC:NH ratios). A significant inverse relationship was identified between BCS and dental score. A Principal Component analysis (PCA) separated the BCS classes on the firs…
format: application/pdf
format: text/html
creator: Emanuela Valle
creator: Federica Raspa
creator: Marzia Giribaldi
creator: Raffaella Barbero
creator: Stefania Bergagna
creator: Sara Antoniazzi
creator: Amy K. Mc Lean
creator: Michela Minero
creator: Laura Cavallarin
subject: Animal Behavior
subject: Veterinary Medicine
subject: Zoology
description: doi:10.7717/peerj.3001
publisher: PeerJ Inc.
rights: © 2017 Valle et al.
abstract: Background The breeding of lactating donkeys is increasing in Western Europe; with it the evaluation of body condition is growing in importance since it is considered a key principle for their welfare. However, assessment of body condition is a complex task, since several factors are involved. The aim of the present study is to investigate which animal-based indicators are the most reliable to describe the body condition of lactating donkeys. For this purpose, new animal-based indicators, which are easy to measure in field conditions (including body measurements, fatty neck score (FNS), dental score), are recorded and their relationship with BCS (a proxy measure for overall adiposity) was assessed. The ones that reveal an association with the BCS are included in an integrated principal component analysis to understand which are the most related to BCS. Methods Fifty-three healthy lactating donkeys of various breeds, including 7 Martina Franca, 10 Ragusano, 2 Romagnolo and 34 crossbreeds, were evaluated. The animal-based indicators that were recorded were: length (OP, olecranon tuber-pinbone and SH, shoulder-hip), heart girth (HG), abdominal circumference (AC), neck length (NL), neck height (NH) and neck thickness (NT) at 0.50 and neck circumference (NC) at 0.25, 0.50 and 0.75, body condition score (BCS) and fatty neck score (FNS). The owners’ evaluation of the BCS was also considered. A dental assessment was performed and the month of lactation and age of each animal was recorded. Results No correlation was found between BCS and the other morphometric body measurements. On the contrary the FNS was correlated with the morphometric measurements of the neck (positive correlation to 0.50 NH and 0.50 NT, 0.50 NC, 0.75 mean NC, and negative correlation to the mean NC:NH and mean NC:NT, 0.50 NC:NT and 0.50 NC:NH ratios). A significant inverse relationship was identified between BCS and dental score. A Principal Component analysis (PCA) separated the BCS classes on the firs…
bibliographic citation: Valle et al. (2017) A functional approach to the body condition assessment of lactating donkeys as a tool for welfare evaluation. PeerJ 5:e3001 https://doi.org/10.7717/peerj.3001
date submitted: 2016-08-16
date accepted: 2017-01-18
issued: 2017-03-28
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Valle
  given name: Emanuela
author list: Agent
  family name: Raspa
  given name: Federica
author list: Agent
  family name: Giribaldi
  given name: Marzia
author list: Agent
  family name: Barbero
  given name: Raffaella
author list: Agent
  family name: Bergagna
  given name: Stefania
author list: Agent
  family name: Antoniazzi
  given name: Sara
author list: Agent
  family name: Mc Lean
  given name: Amy K.
author list: Agent
  family name: Minero
  given name: Michela
author list: Agent
  family name: Cavallarin
  given name: Laura
doi: 10.7717/peerj.3001
volume: 5
issn: 2167-8359
publication name: PeerJ
publication date: 2017-03-28
copyright: ©2017 Valle et al.
attribution name: Valle et al.

Systematic drug repositioning through mining adverse event data in ClinicalTrials.gov
type: item
type: AcademicArticle
description: Drug repositioning (i.e., drug repurposing) is the process of discovering new uses for marketed drugs. Historically, such discoveries were serendipitous. However, the rapid growth in electronic clinical data and text mining tools makes it feasible to systematically identify drugs with the potential to be repurposed. Described here is a novel method of drug repositioning by mining ClinicalTrials.gov. The text mining tools I2E (Linguamatics) and PolyAnalyst (Megaputer) were utilized. An I2E query extracts “Serious Adverse Events” (SAE) data from randomized trials in ClinicalTrials.gov. Through a statistical algorithm, a PolyAnalyst workflow ranks the drugs where the treatment arm has fewer predefined SAEs than the control arm, indicating that potentially the drug is reducing the level of SAE. Hypotheses could then be generated for the new use of these drugs based on the predefined SAE that is indicative of disease (for example, cancer).
format: application/pdf
format: text/html
creator: Eric Wen Su
creator: Todd M. Sanger
subject: Bioinformatics
subject: Clinical Trials
subject: Drugs and Devices
subject: Oncology
subject: Statistics
description: doi:10.7717/peerj.3154
publisher: PeerJ Inc.
rights: © 2017 Su and Sanger
abstract: Drug repositioning (i.e., drug repurposing) is the process of discovering new uses for marketed drugs. Historically, such discoveries were serendipitous. However, the rapid growth in electronic clinical data and text mining tools makes it feasible to systematically identify drugs with the potential to be repurposed. Described here is a novel method of drug repositioning by mining ClinicalTrials.gov. The text mining tools I2E (Linguamatics) and PolyAnalyst (Megaputer) were utilized. An I2E query extracts “Serious Adverse Events” (SAE) data from randomized trials in ClinicalTrials.gov. Through a statistical algorithm, a PolyAnalyst workflow ranks the drugs where the treatment arm has fewer predefined SAEs than the control arm, indicating that potentially the drug is reducing the level of SAE. Hypotheses could then be generated for the new use of these drugs based on the predefined SAE that is indicative of disease (for example, cancer).
bibliographic citation: Su et al. (2017) Systematic drug repositioning through mining adverse event data in ClinicalTrials.gov. PeerJ 5:e3154 https://doi.org/10.7717/peerj.3154
date submitted: 2016-12-08
date accepted: 2017-03-07
issued: 2017-03-23
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Su
  given name: Eric Wen
author list: Agent
  family name: Sanger
  given name: Todd M.
doi: 10.7717/peerj.3154
volume: 5
issn: 2167-8359
publication name: PeerJ
publication date: 2017-03-23
copyright: ©2017 Su and Sanger
attribution name: Su and Sanger

Genetic insights into family group co-occurrence in Cryptocercus punctulatus, a sub-social woodroach from the southern Appalachian Mountains
type: item
type: AcademicArticle
description: The wood-feeding cockroach Cryptocercus punctulatus Scudder (Blattodea: Cryptocercidae) is an important member of the dead wood (saproxylic) community in montane forests of the southeastern United States. However, its population biology remains poorly understood. Here, aspects of family group co-occurrence were characterized to provide basic information that can be extended by studies on the evolution and maintenance of sub-sociality. Broad sampling across the species’ range was coupled with molecular data (mitochondrial DNA (mtDNA) sequences). The primary questions were: (1) what proportion of rotting logs contain two or more different mtDNA haplotypes and how often can this be attributed to multiple families inhabiting the same log, (2) are multi-family logs spatially clustered, and (3) what levels of genetic differentiation among haplotypes exist within a log, and how genetically similar are matrilines of co-occurring family groups? Multi-family logs were identified on the premise that three different mtDNA haplotypes, or two different haplotypes among adult females, is inconsistent with a single family group founded by one male–female pair. Results showed that of the 88 rotting logs from which multiple adult C. punctulatus were sampled, 41 logs (47%) contained two or more mtDNA haplotypes, and at least 19 of these logs (22% overall) were inferred to be inhabited by multiple families. There was no strong evidence for spatial clustering of the latter class of logs. The frequency distribution of nucleotide differences between co-occurring haplotypes was strongly right-skewed, such that most haplotypes were only one or two mutations apart, but more substantial divergences (up to 18 mutations, or 1.6% uncorrected sequence divergence) do occasionally occur within logs. This work represents the first explicit investigation of family group co-occurrence in C. punctulatus, providing a valuable baseline for follow-up studies.
format: application/pdf
format: text/html
creator: Ryan C. Garrick
subject: Entomology
subject: Genetics
subject: Zoology
description: doi:10.7717/peerj.3127
publisher: PeerJ Inc.
rights: © 2017 Garrick
abstract: The wood-feeding cockroach Cryptocercus punctulatus Scudder (Blattodea: Cryptocercidae) is an important member of the dead wood (saproxylic) community in montane forests of the southeastern United States. However, its population biology remains poorly understood. Here, aspects of family group co-occurrence were characterized to provide basic information that can be extended by studies on the evolution and maintenance of sub-sociality. Broad sampling across the species’ range was coupled with molecular data (mitochondrial DNA (mtDNA) sequences). The primary questions were: (1) what proportion of rotting logs contain two or more different mtDNA haplotypes and how often can this be attributed to multiple families inhabiting the same log, (2) are multi-family logs spatially clustered, and (3) what levels of genetic differentiation among haplotypes exist within a log, and how genetically similar are matrilines of co-occurring family groups? Multi-family logs were identified on the premise that three different mtDNA haplotypes, or two different haplotypes among adult females, is inconsistent with a single family group founded by one male–female pair. Results showed that of the 88 rotting logs from which multiple adult C. punctulatus were sampled, 41 logs (47%) contained two or more mtDNA haplotypes, and at least 19 of these logs (22% overall) were inferred to be inhabited by multiple families. There was no strong evidence for spatial clustering of the latter class of logs. The frequency distribution of nucleotide differences between co-occurring haplotypes was strongly right-skewed, such that most haplotypes were only one or two mutations apart, but more substantial divergences (up to 18 mutations, or 1.6% uncorrected sequence divergence) do occasionally occur within logs. This work represents the first explicit investigation of family group co-occurrence in C. punctulatus, providing a valuable baseline for follow-up studies.
bibliographic citation: Garrick (2017) Genetic insights into family group co-occurrence in Cryptocercus punctulatus, a sub-social woodroach from the southern Appalachian Mountains. PeerJ 5:e3127 https://doi.org/10.7717/peerj.3127
date submitted: 2016-10-06
date accepted: 2017-02-27
issued: 2017-03-23
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Garrick
  given name: Ryan C.
doi: 10.7717/peerj.3127
volume: 5
issn: 2167-8359
publication name: PeerJ
publication date: 2017-03-23
copyright: ©2017 Garrick
attribution name: Garrick

Seed germination in a southern Australian temperate seagrass
type: item
type: AcademicArticle
description: In a series of experiments, seeds from a temperate seagrass species, Zostera nigricaulis collected in Port Phillip Bay, Victoria, Australia were exposed to a range of salinities (20 PSU pulse/no pulse, 25 PSU, 30 PSU, 35 PSU), temperatures (13 °C, 17 °C, 22 °C), burial depths (0 cm, 1 cm, 2 cm) and site specific sediment characteristics (fine, medium, coarse) to quantify their impacts on germination rate and maximum overall germination. In southern Australia the seagrass Z. nigricaulis is a common subtidal species; however, little is known about the factors that affect seed germination which is a potential limiting factor in meadow resilience to natural and anthropogenic disturbances. Overall seed germination was low (<20%) with germination decreasing to <10% when seeds were placed in the sediment. When germination of Z. nigricaulis seeds was observed, it was enhanced (greater overall germination and shorter time to germination) when seeds were exposed to a 20 PSU pulse for 24 h, maintained at salinity of 25 PSU, temperatures <13 °C, in sediments with fine or medium grain sand and buried at a depth of <1 cm. These results indicate that germination of Z. nigricaulis seeds under in situ conditions may be seasonally limited by temperatures in southern Australia. Seed germination may be further restricted by salinity as freshwater pulses reaching 20 PSU are typically only observed in Port Phillip Bay following large scale rainfall events. As a result, these populations may be particularly susceptible to disturbance with only a seasonally limited capacity for recovery.
format: application/pdf
format: text/html
creator: Erin Cumming
creator: Jessie C. Jarvis
creator: Craig D.H. Sherman
creator: Paul H. York
creator: Timothy M. Smith
subject: Aquatic and Marine Chemistry
subject: Biosphere Interactions
subject: Marine Biology
subject: Plant Science
description: doi:10.7717/peerj.3114
publisher: PeerJ Inc.
rights: © 2017 Cumming et al.
abstract: In a series of experiments, seeds from a temperate seagrass species, Zostera nigricaulis collected in Port Phillip Bay, Victoria, Australia were exposed to a range of salinities (20 PSU pulse/no pulse, 25 PSU, 30 PSU, 35 PSU), temperatures (13 °C, 17 °C, 22 °C), burial depths (0 cm, 1 cm, 2 cm) and site specific sediment characteristics (fine, medium, coarse) to quantify their impacts on germination rate and maximum overall germination. In southern Australia the seagrass Z. nigricaulis is a common subtidal species; however, little is known about the factors that affect seed germination which is a potential limiting factor in meadow resilience to natural and anthropogenic disturbances. Overall seed germination was low (<20%) with germination decreasing to <10% when seeds were placed in the sediment. When germination of Z. nigricaulis seeds was observed, it was enhanced (greater overall germination and shorter time to germination) when seeds were exposed to a 20 PSU pulse for 24 h, maintained at salinity of 25 PSU, temperatures <13 °C, in sediments with fine or medium grain sand and buried at a depth of <1 cm. These results indicate that germination of Z. nigricaulis seeds under in situ conditions may be seasonally limited by temperatures in southern Australia. Seed germination may be further restricted by salinity as freshwater pulses reaching 20 PSU are typically only observed in Port Phillip Bay following large scale rainfall events. As a result, these populations may be particularly susceptible to disturbance with only a seasonally limited capacity for recovery.
bibliographic citation: Cumming et al. (2017) Seed germination in a southern Australian temperate seagrass. PeerJ 5:e3114 https://doi.org/10.7717/peerj.3114
date submitted: 2016-12-12
date accepted: 2017-02-22
issued: 2017-03-23
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Cumming
  given name: Erin
author list: Agent
  family name: Jarvis
  given name: Jessie C.
author list: Agent
  family name: Sherman
  given name: Craig D.H.
author list: Agent
  family name: York
  given name: Paul H.
author list: Agent
  family name: Smith
  given name: Timothy M.
doi: 10.7717/peerj.3114
volume: 5
issn: 2167-8359
publication name: PeerJ
publication date: 2017-03-23
copyright: ©2017 Cumming et al.
attribution name: Cumming et al.

Basal tolerance to heat and cold exposure of the spotted wing drosophila, Drosophila suzukii
type: item
type: AcademicArticle
description: The spotted wing Drosophila, Drosophila suzukii, is a new pest in Europe and America which causes severe damages, mostly to stone fruit crops. Temperature and humidity are among the most important abiotic factors governing insect development and fitness. In many situations, temperature can become stressful thus compromising survival. The ability to cope with thermal stress depends on basal level of thermal tolerance. Basic knowledge on temperature-dependent mortality of D. suzukii is essential to facilitate management of this pest. The objective of the present study was to investigate D. suzukii basal cold and heat tolerance. Adults and pupae were subjected to six low temperatures (−5–7.5 °C) and seven high temperatures (30–37 °C) for various durations, and survival-time-temperature relationships were investigated. Data showed that males were globally more cold tolerant than females. At temperature above 5 °C, adult cold mortality became minor even after prolonged exposures (e.g., only 20% mortality after one month at 7.5 °C). Heat tolerance of males was lower than that of females at the highest tested temperatures (34, 35 and 37 °C). Pupae appeared much less cold tolerant than adults at all temperatures (e.g., Lt50 at 5° C: 4–5 d for adults vs. 21 h for pupae). Pupae were more heat tolerant than adults at the most extreme high temperatures (e.g., Lt50 at 37 °C: 30 min for adults vs. 4 h for pupae). The pupal thermal tolerance was further investigated under low vs. high humidity. Low relative humidity did not affect pupal cold survival, but it reduced survival under heat stress. Overall, this study shows that survival of D. suzukii under heat and cold conditions can vary with stress intensity, duration, humidity, sex and stage, and the methodological approach used here, which was based on thermal tolerance landscapes, provides a comprehensive description of D. suzukiithermal tolerance and limits.
format: application/pdf
format: text/html
creator: Thomas Enriquez
creator: Hervé Colinet
subject: Biosphere Interactions
subject: Ecology
subject: Entomology
subject: Environmental Sciences
subject: Natural Resource Management
description: doi:10.7717/peerj.3112
publisher: PeerJ Inc.
rights: © 2017 Enriquez and Colinet
abstract: The spotted wing Drosophila, Drosophila suzukii, is a new pest in Europe and America which causes severe damages, mostly to stone fruit crops. Temperature and humidity are among the most important abiotic factors governing insect development and fitness. In many situations, temperature can become stressful thus compromising survival. The ability to cope with thermal stress depends on basal level of thermal tolerance. Basic knowledge on temperature-dependent mortality of D. suzukii is essential to facilitate management of this pest. The objective of the present study was to investigate D. suzukii basal cold and heat tolerance. Adults and pupae were subjected to six low temperatures (−5–7.5 °C) and seven high temperatures (30–37 °C) for various durations, and survival-time-temperature relationships were investigated. Data showed that males were globally more cold tolerant than females. At temperature above 5 °C, adult cold mortality became minor even after prolonged exposures (e.g., only 20% mortality after one month at 7.5 °C). Heat tolerance of males was lower than that of females at the highest tested temperatures (34, 35 and 37 °C). Pupae appeared much less cold tolerant than adults at all temperatures (e.g., Lt50 at 5° C: 4–5 d for adults vs. 21 h for pupae). Pupae were more heat tolerant than adults at the most extreme high temperatures (e.g., Lt50 at 37 °C: 30 min for adults vs. 4 h for pupae). The pupal thermal tolerance was further investigated under low vs. high humidity. Low relative humidity did not affect pupal cold survival, but it reduced survival under heat stress. Overall, this study shows that survival of D. suzukii under heat and cold conditions can vary with stress intensity, duration, humidity, sex and stage, and the methodological approach used here, which was based on thermal tolerance landscapes, provides a comprehensive description of D. suzukiithermal tolerance and limits.
bibliographic citation: Enriquez et al. (2017) Basal tolerance to heat and cold exposure of the spotted wing drosophila, Drosophila suzukii. PeerJ 5:e3112 https://doi.org/10.7717/peerj.3112
date submitted: 2016-11-24
date accepted: 2017-02-21
issued: 2017-03-23
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Enriquez
  given name: Thomas
author list: Agent
  family name: Colinet
  given name: Hervé
doi: 10.7717/peerj.3112
volume: 5
issn: 2167-8359
publication name: PeerJ
publication date: 2017-03-23
copyright: ©2017 Enriquez and Colinet
attribution name: Enriquez and Colinet

Analysis of different vibration patterns to guide blind people
type: item
type: AcademicArticle
description: The literature indicates the best vibration positions and frequencies on the human body where tactile information is transmitted. However, there is a lack of knowledge about how to combine tactile stimuli for navigation. The aim of this study is to compare different vibration patterns outputted to blind people and to determine the most intuitive vibration patterns to indicate direction for navigation purposes through a tactile belt. The vibration patterns that stimulate the front side of the waist are preferred for indicating direction. Vibration patterns applied on the back side of the waist could be suitable for sending messages such as stop.
format: application/pdf
format: text/html
creator: Juan V. Durá-Gil
creator: Bruno Bazuelo-Ruiz
creator: David Moro-Pérez
creator: Fernando Mollà-Domenech
subject: Kinesiology
subject: Psychiatry and Psychology
subject: Human-Computer Interaction
description: doi:10.7717/peerj.3082
publisher: PeerJ Inc.
rights: © 2017 Durá-Gil et al.
abstract: The literature indicates the best vibration positions and frequencies on the human body where tactile information is transmitted. However, there is a lack of knowledge about how to combine tactile stimuli for navigation. The aim of this study is to compare different vibration patterns outputted to blind people and to determine the most intuitive vibration patterns to indicate direction for navigation purposes through a tactile belt. The vibration patterns that stimulate the front side of the waist are preferred for indicating direction. Vibration patterns applied on the back side of the waist could be suitable for sending messages such as stop.
bibliographic citation: Durá-Gil et al. (2017) Analysis of different vibration patterns to guide blind people. PeerJ 5:e3082 https://doi.org/10.7717/peerj.3082
date submitted: 2016-07-25
date accepted: 2017-02-12
issued: 2017-03-23
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Durá-Gil
  given name: Juan V.
author list: Agent
  family name: Bazuelo-Ruiz
  given name: Bruno
author list: Agent
  family name: Moro-Pérez
  given name: David
author list: Agent
  family name: Mollà-Domenech
  given name: Fernando
doi: 10.7717/peerj.3082
volume: 5
issn: 2167-8359
publication name: PeerJ
publication date: 2017-03-23
copyright: ©2017 Durá-Gil et al.
attribution name: Durá-Gil et al.

Are floating algal mats a refuge from hypoxia for estuarine invertebrates?
type: item
type: AcademicArticle
description: Eutrophic aquatic habitats are characterized by the proliferation of vegetation leading to a large standing biomass that upon decomposition may create hypoxic (low-oxygen) conditions. This is indeed the case in nutrient impacted estuaries of Prince Edward Island, Canada, where macroalgae, from the genus Ulva, form submerged ephemeral mats. Hydrological forces and gases released from photosynthesis and decomposition lead to these mats occasionally floating to the water’s surface, henceforth termed floating mats. Here, we explore the hypothesis that floating mats are refugia during periods of sustained hypoxia/anoxia and examine how the invertebrate community responds to it. Floating mats were not always present, so in the first year (2013) sampling was attempted monthly and limited to when both floating and submerged mats occurred. In the subsequent year sampling was weekly, but at only one estuary due to logistical constraints from increased sampling frequency, and was not limited to when both mat types occurred. Water temperature, salinity, and pH were monitored bi-weekly with dissolved oxygen concentration measured hourly. The floating and submerged assemblages shared many of the same taxa but were statistically distinct communities; submerged mats tended to have a greater proportion of benthic animals and floating mats had more mobile invertebrates and insects. In 2014, sampling happened to occur in the weeks before the onset of anoxia, during 113 consecutive hours of sustained anoxia, and for four weeks after normoxic conditions returned. The invertebrate community on floating mats appeared to be unaffected by anoxia, indicating that these mats may be refugia during times of oxygen stress. Conversely, there was a dramatic decrease in animal abundances that remained depressed on submerged mats for two weeks. Cluster analysis revealed that the submerged mat communities from before the onset of anoxia and four weeks after anoxia were highly similar to each other, i…
format: application/pdf
format: text/html
creator: Michael R.S. Coffin
creator: Kyle M. Knysh
creator: Emma F. Theriault
creator: Christina C. Pater
creator: Simon C. Courtenay
creator: Michael R. van den Heuvel
subject: Animal Behavior
subject: Ecology
subject: Ecotoxicology
subject: Environmental Sciences
subject: Marine Biology
description: doi:10.7717/peerj.3080
publisher: PeerJ Inc.
rights: © 2017 Coffin et al.
abstract: Eutrophic aquatic habitats are characterized by the proliferation of vegetation leading to a large standing biomass that upon decomposition may create hypoxic (low-oxygen) conditions. This is indeed the case in nutrient impacted estuaries of Prince Edward Island, Canada, where macroalgae, from the genus Ulva, form submerged ephemeral mats. Hydrological forces and gases released from photosynthesis and decomposition lead to these mats occasionally floating to the water’s surface, henceforth termed floating mats. Here, we explore the hypothesis that floating mats are refugia during periods of sustained hypoxia/anoxia and examine how the invertebrate community responds to it. Floating mats were not always present, so in the first year (2013) sampling was attempted monthly and limited to when both floating and submerged mats occurred. In the subsequent year sampling was weekly, but at only one estuary due to logistical constraints from increased sampling frequency, and was not limited to when both mat types occurred. Water temperature, salinity, and pH were monitored bi-weekly with dissolved oxygen concentration measured hourly. The floating and submerged assemblages shared many of the same taxa but were statistically distinct communities; submerged mats tended to have a greater proportion of benthic animals and floating mats had more mobile invertebrates and insects. In 2014, sampling happened to occur in the weeks before the onset of anoxia, during 113 consecutive hours of sustained anoxia, and for four weeks after normoxic conditions returned. The invertebrate community on floating mats appeared to be unaffected by anoxia, indicating that these mats may be refugia during times of oxygen stress. Conversely, there was a dramatic decrease in animal abundances that remained depressed on submerged mats for two weeks. Cluster analysis revealed that the submerged mat communities from before the onset of anoxia and four weeks after anoxia were highly similar to each other, i…
bibliographic citation: Coffin et al. (2017) Are floating algal mats a refuge from hypoxia for estuarine invertebrates?. PeerJ 5:e3080 https://doi.org/10.7717/peerj.3080
date submitted: 2016-11-04
date accepted: 2017-02-10
issued: 2017-03-23
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Coffin
  given name: Michael R.S.
author list: Agent
  family name: Knysh
  given name: Kyle M.
author list: Agent
  family name: Theriault
  given name: Emma F.
author list: Agent
  family name: Pater
  given name: Christina C.
author list: Agent
  family name: Courtenay
  given name: Simon C.
author list: Agent
  family name: van den Heuvel
  given name: Michael R.
doi: 10.7717/peerj.3080
volume: 5
issn: 2167-8359
publication name: PeerJ
publication date: 2017-03-23
copyright: ©2017 Coffin et al.
attribution name: Coffin et al.

Climate change promotes hybridisation between deeply divergent species
type: item
type: AcademicArticle
description: Rare hybridisations between deeply divergent animal species have been reported for decades in a wide range of taxa, but have often remained unexplained, mainly considered chance events and reported as anecdotal. Here, we combine field observations with long-term data concerning natural hybridisations, climate, land-use, and field-validated species distribution models for two deeply divergent and naturally sympatric toad species in Europe (Bufo bufo and Bufotes viridis species groups). We show that climate warming and seasonal extreme temperatures are conspiring to set the scene for these maladaptive hybridisations, by differentially affecting life-history traits of both species. Our results identify and provide evidence of an ultimate cause for such events, and reveal that the potential influence of climate change on interspecific hybridisations goes far beyond closely related species. Furthermore, climate projections suggest that the chances for these events will steadily increase in the near future.
format: application/pdf
format: text/html
creator: Daniele Canestrelli
creator: Roberta Bisconti
creator: Andrea Chiocchio
creator: Luigi Maiorano
creator: Mauro Zampiglia
creator: Giuseppe Nascetti
subject: Biosphere Interactions
subject: Climate Change Biology
subject: Ecology
subject: Evolutionary Studies
subject: Zoology
description: doi:10.7717/peerj.3072
publisher: PeerJ Inc.
rights: © 2017 Canestrelli et al.
abstract: Rare hybridisations between deeply divergent animal species have been reported for decades in a wide range of taxa, but have often remained unexplained, mainly considered chance events and reported as anecdotal. Here, we combine field observations with long-term data concerning natural hybridisations, climate, land-use, and field-validated species distribution models for two deeply divergent and naturally sympatric toad species in Europe (Bufo bufo and Bufotes viridis species groups). We show that climate warming and seasonal extreme temperatures are conspiring to set the scene for these maladaptive hybridisations, by differentially affecting life-history traits of both species. Our results identify and provide evidence of an ultimate cause for such events, and reveal that the potential influence of climate change on interspecific hybridisations goes far beyond closely related species. Furthermore, climate projections suggest that the chances for these events will steadily increase in the near future.
bibliographic citation: Canestrelli et al. (2017) Climate change promotes hybridisation between deeply divergent species. PeerJ 5:e3072 https://doi.org/10.7717/peerj.3072
date submitted: 2016-12-09
date accepted: 2017-02-07
issued: 2017-03-23
is part of: PeerJ
license: http://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Canestrelli
  given name: Daniele
author list: Agent
  family name: Bisconti
  given name: Roberta
author list: Agent
  family name: Chiocchio
  given name: Andrea
author list: Agent
  family name: Maiorano
  given name: Luigi
author list: Agent
  family name: Zampiglia
  given name: Mauro
author list: Agent
  family name: Nascetti
  given name: Giuseppe
doi: 10.7717/peerj.3072
volume: 5
issn: 2167-8359
publication name: PeerJ
publication date: 2017-03-23
copyright: © 2017 Canestrelli et al.
attribution name: Canestrelli et al.

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