PeerJ
type: channel
link: https://peerj.com/articles/
description: Articles published in PeerJ
publisher: PeerJ Inc.
publication name: PeerJ
issn: 2167-8359
items: Gas chromatography (GC) fingerprinting and immunomodulatory activity of polysaccharide from the rhizome of Menispermum dauricum DC
items: Daylight savings time transition and the incidence of femur fractures in the older population: a nationwide registry-based study
items: Somatization symptoms—prevalence and risk, stress and resilience factors among medical and dental students at a mid-sized German university
items: Users’ needs for a digital smoking cessation application and how to address them: A mixed-methods study
items: CCL25/CCR9 interaction promotes the malignant behavior of salivary adenoid cystic carcinoma via the PI3K/AKT signaling pathway
items: Regional impact of large-scale climate oscillations on ice out variability in New Brunswick and Maine
items: Identifying important ecosystem service areas based on distributions of ecosystem services in the Beijing–Tianjin–Hebei region, China
items: A simple hierarchical model for heterogeneity in the evolutionary correlation on a phylogenetic tree
items: Incorporating nonlinearity with generalized functional responses to simulate multiple predator effects
items: Enhancing georeferenced biodiversity inventories: automated information extraction from literature records reveal the gaps

Gas chromatography (GC) fingerprinting and immunomodulatory activity of polysaccharide from the rhizome of Menispermum dauricum DC
type: item
type: AcademicArticle
description: This research aimed to establish the gas chromatography (GC) fingerprints and examine the immunomodulatory activity of the rhizome of Menispermum dauricum polysaccharides. In this study, the preparation conditions were optimized by the response surface method (RSM). GC is an effective and sensitive technique employed to measure the composition of monosaccharides; the GC fingerprints of total polysaccharides from 10 batches of the rhizome of M. dauricum (tMDP) were established, and chemometrics methods were adopted to examine the differences and similarities of tMDP from distinct regions. The similarity evaluation illustrated that the polysaccharides derived from the rhizome of M. dauricum from different origins were highly similar. The results of principal components analysis (PCA) illustrated that all the tMDPs may be integrated into one group within the 95% confidence interval, but the rhizome of M. dauricum from different origins could also be distinguished in the plot of PCA scores. Then, the major bioactive fraction MDP was purified and obtained by column chromatography. Our previous study showed that MDP exhibited significant immunomodulatory activity, but the mechanism of the in vitro immunomodulatory activity of MDP is unclear. The macrophage activation induced by MDP was abolished when Toll-like receptor 4 (TLR4) signaling was knocked down by the TLR4 inhibitor. Furthermore, western blot analysis illustrated that MDP activated RAW264.7 cells through MAPKs and NFκB pathways induced by TLR4. This research offers a theoretical foundation for quality control and additional study as a potential immunomodulator of MDP.
format: application/pdf
format: text/html
creator: Pei Yang
creator: Yang Zhai
creator: Yan Ma
creator: Beibei Mao
creator: Fengshan Wang
creator: Li Li
creator: Lijuan Luan
creator: Yuhong Liu
subject: Biochemistry
subject: Cell Biology
subject: Molecular Biology
subject: Immunology
description: doi:10.7717/peerj.13946
publisher: PeerJ Inc.
rights: © 2022 Yang et al.
abstract: This research aimed to establish the gas chromatography (GC) fingerprints and examine the immunomodulatory activity of the rhizome of Menispermum dauricum polysaccharides. In this study, the preparation conditions were optimized by the response surface method (RSM). GC is an effective and sensitive technique employed to measure the composition of monosaccharides; the GC fingerprints of total polysaccharides from 10 batches of the rhizome of M. dauricum (tMDP) were established, and chemometrics methods were adopted to examine the differences and similarities of tMDP from distinct regions. The similarity evaluation illustrated that the polysaccharides derived from the rhizome of M. dauricum from different origins were highly similar. The results of principal components analysis (PCA) illustrated that all the tMDPs may be integrated into one group within the 95% confidence interval, but the rhizome of M. dauricum from different origins could also be distinguished in the plot of PCA scores. Then, the major bioactive fraction MDP was purified and obtained by column chromatography. Our previous study showed that MDP exhibited significant immunomodulatory activity, but the mechanism of the in vitro immunomodulatory activity of MDP is unclear. The macrophage activation induced by MDP was abolished when Toll-like receptor 4 (TLR4) signaling was knocked down by the TLR4 inhibitor. Furthermore, western blot analysis illustrated that MDP activated RAW264.7 cells through MAPKs and NFκB pathways induced by TLR4. This research offers a theoretical foundation for quality control and additional study as a potential immunomodulator of MDP.
bibliographic citation: Yang et al. (2022) Gas chromatography (GC) fingerprinting and immunomodulatory activity of polysaccharide from the rhizome of Menispermum dauricum DC. PeerJ 10:e13946 https://doi.org/10.7717/peerj.13946
date submitted: 2022-07-04
date accepted: 2022-08-03
issued: 2022-08-22
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Yang
  given name: Pei
author list: Agent
  family name: Zhai
  given name: Yang
author list: Agent
  family name: Ma
  given name: Yan
author list: Agent
  family name: Mao
  given name: Beibei
author list: Agent
  family name: Wang
  given name: Fengshan
author list: Agent
  family name: Li
  given name: Li
author list: Agent
  family name: Luan
  given name: Lijuan
author list: Agent
  family name: Liu
  given name: Yuhong
doi: 10.7717/peerj.13946
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-08-22
copyright: © 2022 Yang et al.
attribution name: Yang et al.

Daylight savings time transition and the incidence of femur fractures in the older population: a nationwide registry-based study
type: item
type: AcademicArticle
description: Background Daylight Savings Time (DST) transition is known to cause sleep disruption, and thus may increase the incidence of injuries and accidents during the week following the transition. The aim of this study was to assess the incidence of femur fractures after DST transition. Methods We conducted retrospective population-based register study. All Finnish patients 70 years or older who were admitted to hospital due to femur fracture between 1997 and 2020 were gathered from the Finnish National Hospital Discharge Register. Negative binomial regression with 95% confidence intervals (CI) was used to evaluate the incidence of femur fractures after DST transition. Results The data included a total of 112,658 femur fractures during the study period between 1997 and 2020, with an annual mean (SD) of 4,694 (206) fractures. The incidence of femur fractures decreased at the beginning of the study period from 968 to 688 per 100,000 person-years between 1997 and 2007. The weekly mean of femur fractures remained lower during the summer (from 130 to 150 per 100,000 person-weeks) than in winter (from 160 to 180 per 100,000 person-weeks). Incidence rate ratio for the Monday following DST transition was 1.10 (CI [0.98–1.24]) in spring and 1.10 (CI [0.97–1.24]) in fall, and for the whole week 1.07 (CI [1.01–1.14]) in spring and 0.97 (CI [0.83–1.13]) in fall. Conclusion We found weak evidence that the incidence of femur fractures increases after DST transition in the spring.
format: application/pdf
format: text/html
creator: Ville Ponkilainen
creator: Topias Koukkula
creator: Mikko Uimonen
creator: Ville M. Mattila
creator: Ilari Kuitunen
creator: Aleksi Reito
subject: Epidemiology
subject: Geriatrics
subject: Orthopedics
subject: Public Health
description: doi:10.7717/peerj.13672
publisher: PeerJ Inc.
rights: © 2022 Ponkilainen et al.
abstract: Background Daylight Savings Time (DST) transition is known to cause sleep disruption, and thus may increase the incidence of injuries and accidents during the week following the transition. The aim of this study was to assess the incidence of femur fractures after DST transition. Methods We conducted retrospective population-based register study. All Finnish patients 70 years or older who were admitted to hospital due to femur fracture between 1997 and 2020 were gathered from the Finnish National Hospital Discharge Register. Negative binomial regression with 95% confidence intervals (CI) was used to evaluate the incidence of femur fractures after DST transition. Results The data included a total of 112,658 femur fractures during the study period between 1997 and 2020, with an annual mean (SD) of 4,694 (206) fractures. The incidence of femur fractures decreased at the beginning of the study period from 968 to 688 per 100,000 person-years between 1997 and 2007. The weekly mean of femur fractures remained lower during the summer (from 130 to 150 per 100,000 person-weeks) than in winter (from 160 to 180 per 100,000 person-weeks). Incidence rate ratio for the Monday following DST transition was 1.10 (CI [0.98–1.24]) in spring and 1.10 (CI [0.97–1.24]) in fall, and for the whole week 1.07 (CI [1.01–1.14]) in spring and 0.97 (CI [0.83–1.13]) in fall. Conclusion We found weak evidence that the incidence of femur fractures increases after DST transition in the spring.
bibliographic citation: Ponkilainen et al. (2022) Daylight savings time transition and the incidence of femur fractures in the older population: a nationwide registry-based study. PeerJ 10:e13672 https://doi.org/10.7717/peerj.13672
date submitted: 2022-02-09
date accepted: 2022-06-12
issued: 2022-08-19
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Ponkilainen
  given name: Ville
author list: Agent
  family name: Koukkula
  given name: Topias
author list: Agent
  family name: Uimonen
  given name: Mikko
author list: Agent
  family name: Mattila
  given name: Ville M.
author list: Agent
  family name: Kuitunen
  given name: Ilari
author list: Agent
  family name: Reito
  given name: Aleksi
doi: 10.7717/peerj.13672
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-08-19
copyright: ©2022 Ponkilainen et al.
attribution name: Ponkilainen et al.

Somatization symptoms—prevalence and risk, stress and resilience factors among medical and dental students at a mid-sized German university
type: item
type: AcademicArticle
description: Objective Previous studies have shown that an increased prevalence of mental illness can be found among medical and dental students. Among these, somatization symptoms are severely understudied. The present study examined the prevalence of somatization symptoms in a subpopulation of medical and dental students and aimed at finding associated risk and resilience factors. Methods A cross-sectional survey was conducted using a self-reporting questionnaire, including the SOMS-2, the Becks-Depression-Inventory-II (BDI-II), the NEO-Five-Factor-Inventory, and a questionnaire on socio-demographics for possible risk and resilience factors. A total of 271 medical and dental students of a mid-sized German university completed the questionnaire. Results The Somatization index yielded a mean of 9.12 symptoms for the total sample, which is 1.2 SD higher than the reported norm. A total of 50.7% of the medical students and 63.6% of the dental students transcend a critical somatization score. Significant positive associations for eight general risk factors, four university related stress factors, and a significant negative association for seven resilience factors were found. Conclusion Medical and even more dental students at the studied university showed a high burden of somatoform complaints. Also, factors were found that could be of etiological relevance and others that could be used to enhance resilience. Both could present an opportunity for the prevention of somatization disorders but prospective and multicenter studies with an aged-matched comparison group are needed to obtain a more accurate overview.
format: application/pdf
format: text/html
creator: Oskar Feussner
creator: Carolin Rehnisch
creator: Nadja Rabkow
creator: Stefan Watzke
subject: Dentistry
subject: Psychiatry and Psychology
subject: Science and Medical Education
subject: Statistics
subject: Mental Health
description: doi:10.7717/peerj.13803
publisher: PeerJ Inc.
rights: © 2022 Feussner et al.
abstract: Objective Previous studies have shown that an increased prevalence of mental illness can be found among medical and dental students. Among these, somatization symptoms are severely understudied. The present study examined the prevalence of somatization symptoms in a subpopulation of medical and dental students and aimed at finding associated risk and resilience factors. Methods A cross-sectional survey was conducted using a self-reporting questionnaire, including the SOMS-2, the Becks-Depression-Inventory-II (BDI-II), the NEO-Five-Factor-Inventory, and a questionnaire on socio-demographics for possible risk and resilience factors. A total of 271 medical and dental students of a mid-sized German university completed the questionnaire. Results The Somatization index yielded a mean of 9.12 symptoms for the total sample, which is 1.2 SD higher than the reported norm. A total of 50.7% of the medical students and 63.6% of the dental students transcend a critical somatization score. Significant positive associations for eight general risk factors, four university related stress factors, and a significant negative association for seven resilience factors were found. Conclusion Medical and even more dental students at the studied university showed a high burden of somatoform complaints. Also, factors were found that could be of etiological relevance and others that could be used to enhance resilience. Both could present an opportunity for the prevention of somatization disorders but prospective and multicenter studies with an aged-matched comparison group are needed to obtain a more accurate overview.
bibliographic citation: Feussner et al. (2022) Somatization symptoms—prevalence and risk, stress and resilience factors among medical and dental students at a mid-sized German university. PeerJ 10:e13803 https://doi.org/10.7717/peerj.13803
date submitted: 2022-03-03
date accepted: 2022-07-07
issued: 2022-08-19
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Feussner
  given name: Oskar
author list: Agent
  family name: Rehnisch
  given name: Carolin
author list: Agent
  family name: Rabkow
  given name: Nadja
author list: Agent
  family name: Watzke
  given name: Stefan
doi: 10.7717/peerj.13803
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-08-19
copyright: ©2022 Feussner et al.
attribution name: Feussner et al.

Users’ needs for a digital smoking cessation application and how to address them: A mixed-methods study
type: item
type: AcademicArticle
description: Background Despite their increasing prevalence and potential, eHealth applications for behavior change suffer from a lack of adherence and from dropout. Advances in virtual coach technology provide new opportunities to improve this. However, these applications still do not always offer what people need. We, therefore, need a better understanding of people’s needs and how to address these, based on both actual experiences of users and their reflections on envisioned scenarios. Methods We conducted a longitudinal study in which 671 smokers interacted with a virtual coach in five sessions. The virtual coach assigned them a new preparatory activity for quitting smoking or increasing physical activity in each session. Participants provided feedback on the activity in the next session. After the five sessions, participants were asked to describe barriers and motivators for doing their activities. In addition, they provided their views on videos of scenarios such as receiving motivational messages. To understand users’ needs, we took a mixed-methods approach. This approach triangulated findings from qualitative data, quantitative data, and the literature. Results We identified 14 main themes that describe people’s views of their current and future behaviors concerning an eHealth application. These themes relate to the behaviors themselves, the users, other parties involved in a behavior, and the environment. The most prevalent theme was the perceived usefulness of behaviors, especially whether they were informative, helpful, motivating, or encouraging. The timing and intensity of behaviors also mattered. With regards to the users, their perceived importance of and motivation to change, autonomy, and personal characteristics were major themes. Another important role was played by other parties that may be involved in a behavior, such as general practitioners or virtual coaches. Here, the themes of companionableness, accountability, and nature of the other party (i.e., human…
format: application/pdf
format: text/html
creator: Nele Albers
creator: Mark A. Neerincx
creator: Kristell M. Penfornis
creator: Willem-Paul Brinkman
subject: Health Policy
subject: Public Health
subject: Respiratory Medicine
subject: Human-Computer Interaction
description: doi:10.7717/peerj.13824
publisher: PeerJ Inc.
rights: © 2022 Albers et al.
abstract: Background Despite their increasing prevalence and potential, eHealth applications for behavior change suffer from a lack of adherence and from dropout. Advances in virtual coach technology provide new opportunities to improve this. However, these applications still do not always offer what people need. We, therefore, need a better understanding of people’s needs and how to address these, based on both actual experiences of users and their reflections on envisioned scenarios. Methods We conducted a longitudinal study in which 671 smokers interacted with a virtual coach in five sessions. The virtual coach assigned them a new preparatory activity for quitting smoking or increasing physical activity in each session. Participants provided feedback on the activity in the next session. After the five sessions, participants were asked to describe barriers and motivators for doing their activities. In addition, they provided their views on videos of scenarios such as receiving motivational messages. To understand users’ needs, we took a mixed-methods approach. This approach triangulated findings from qualitative data, quantitative data, and the literature. Results We identified 14 main themes that describe people’s views of their current and future behaviors concerning an eHealth application. These themes relate to the behaviors themselves, the users, other parties involved in a behavior, and the environment. The most prevalent theme was the perceived usefulness of behaviors, especially whether they were informative, helpful, motivating, or encouraging. The timing and intensity of behaviors also mattered. With regards to the users, their perceived importance of and motivation to change, autonomy, and personal characteristics were major themes. Another important role was played by other parties that may be involved in a behavior, such as general practitioners or virtual coaches. Here, the themes of companionableness, accountability, and nature of the other party (i.e., human…
bibliographic citation: Albers et al. (2022) Users’ needs for a digital smoking cessation application and how to address them: A mixed-methods study. PeerJ 10:e13824 https://doi.org/10.7717/peerj.13824
date submitted: 2022-04-01
date accepted: 2022-07-10
issued: 2022-08-19
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Albers
  given name: Nele
author list: Agent
  family name: Neerincx
  given name: Mark A.
author list: Agent
  family name: Penfornis
  given name: Kristell M.
author list: Agent
  family name: Brinkman
  given name: Willem-Paul
doi: 10.7717/peerj.13824
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-08-19
copyright: © 2022 Albers et al.
attribution name: Albers et al.

CCL25/CCR9 interaction promotes the malignant behavior of salivary adenoid cystic carcinoma via the PI3K/AKT signaling pathway
type: item
type: AcademicArticle
description: Background CC chemokine receptor 9 (CCR9), an organ-specific chemokine receptor, interacts with its exclusive ligand CCL25 to promote tumor proliferation and metastasis. However, the effect of CCR9 on salivary adenoid cystic carcinoma (SACC) malignant behavior remains unknown. This study aimed to investigate the specific molecular mechanism by which CCR9/CCL25 modulates malignant progression in SACC. Methods Immunohistochemistry staining and RT–qPCR analyses were performed to detect the correlation of CCR9 expression and tumor progression-associated markers in SACC. In vitro, SACC cell proliferation and apoptosis were evaluated using Cell Counting Kit-8 and colon formation, and cell migration and invasion were detected by wound healing and transwell assays. Vercirnon was used as an inhibitor of CCR9, and LY294002 was used as an inhibitor of the PI3K/AKT pathway in this study. Western blot and RT–qPCR assays were carried out to measure the downstream factors of the interaction of CCL25 and CCR9. The effect of CCL25 on the development of SACC in vivo was examined by a xenograft tumor model in nude mice following CCL25, Vercirnon and LY294002 treatment. Results CCR9 was highly expressed in SACC compared with adjacent salivary gland tissues, and its level was associated with tumor proliferation and metastases. CCL25 enhanced cell proliferation, migration, and invasion through its interaction with CCR9 and exerted an antiapoptotic effect on SACC cells. Targeting CCR9 via Vercirnon significantly reduced the phosphorylation level of AKT induced by CCL25. CCL25/CCR9 could activate its downstream factors through the PI3K/AKT signaling pathway, such as cyclin D1, BCL2 and SLUG, thus promoting SACC cell proliferation, antiapoptosis, invasion and metastasis. The in vivo data from the xenograft mouse models further proved that CCL25 administration promoted malignant tumor progression by activating the PI3K/AKT pathway. Conclusion The interaction of CCL25 and CCR9 promotes tumor …
format: application/pdf
format: text/html
creator: Songling Chai
creator: Zhihao Wen
creator: Rongxin Zhang
creator: Yuwen Bai
creator: Jing Liu
creator: Juanjuan Li
creator: Wenyao Kongling
creator: Weixian Chen
creator: Fu Wang
creator: Lu Gao
subject: Cell Biology
subject: Molecular Biology
subject: Dentistry
subject: Oncology
description: doi:10.7717/peerj.13844
publisher: PeerJ Inc.
rights: © 2022 Chai et al.
abstract: Background CC chemokine receptor 9 (CCR9), an organ-specific chemokine receptor, interacts with its exclusive ligand CCL25 to promote tumor proliferation and metastasis. However, the effect of CCR9 on salivary adenoid cystic carcinoma (SACC) malignant behavior remains unknown. This study aimed to investigate the specific molecular mechanism by which CCR9/CCL25 modulates malignant progression in SACC. Methods Immunohistochemistry staining and RT–qPCR analyses were performed to detect the correlation of CCR9 expression and tumor progression-associated markers in SACC. In vitro, SACC cell proliferation and apoptosis were evaluated using Cell Counting Kit-8 and colon formation, and cell migration and invasion were detected by wound healing and transwell assays. Vercirnon was used as an inhibitor of CCR9, and LY294002 was used as an inhibitor of the PI3K/AKT pathway in this study. Western blot and RT–qPCR assays were carried out to measure the downstream factors of the interaction of CCL25 and CCR9. The effect of CCL25 on the development of SACC in vivo was examined by a xenograft tumor model in nude mice following CCL25, Vercirnon and LY294002 treatment. Results CCR9 was highly expressed in SACC compared with adjacent salivary gland tissues, and its level was associated with tumor proliferation and metastases. CCL25 enhanced cell proliferation, migration, and invasion through its interaction with CCR9 and exerted an antiapoptotic effect on SACC cells. Targeting CCR9 via Vercirnon significantly reduced the phosphorylation level of AKT induced by CCL25. CCL25/CCR9 could activate its downstream factors through the PI3K/AKT signaling pathway, such as cyclin D1, BCL2 and SLUG, thus promoting SACC cell proliferation, antiapoptosis, invasion and metastasis. The in vivo data from the xenograft mouse models further proved that CCL25 administration promoted malignant tumor progression by activating the PI3K/AKT pathway. Conclusion The interaction of CCL25 and CCR9 promotes tumor …
bibliographic citation: Chai et al. (2022) CCL25/CCR9 interaction promotes the malignant behavior of salivary adenoid cystic carcinoma via the PI3K/AKT signaling pathway. PeerJ 10:e13844 https://doi.org/10.7717/peerj.13844
date submitted: 2022-03-21
date accepted: 2022-07-14
issued: 2022-08-19
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Chai
  given name: Songling
author list: Agent
  family name: Wen
  given name: Zhihao
author list: Agent
  family name: Zhang
  given name: Rongxin
author list: Agent
  family name: Bai
  given name: Yuwen
author list: Agent
  family name: Liu
  given name: Jing
author list: Agent
  family name: Li
  given name: Juanjuan
author list: Agent
  family name: Kongling
  given name: Wenyao
author list: Agent
  family name: Chen
  given name: Weixian
author list: Agent
  family name: Wang
  given name: Fu
author list: Agent
  family name: Gao
  given name: Lu
doi: 10.7717/peerj.13844
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-08-19
copyright: © 2022 Chai et al.
attribution name: Chai et al.

Regional impact of large-scale climate oscillations on ice out variability in New Brunswick and Maine
type: item
type: AcademicArticle
description: The available ice out (the date of disappearance of ice from a water body) records were analyzed from four relatively closely spaced lakes in southwestern New Brunswick (Harvey, Oromocto, Skiff) and eastern Maine (West Grand Lake), with the longest set of available observations being for Oromocto Lake starting in 1876. Results of a coherence analysis carried out on the ice out data from the four lakes indicates that there is regional coherence and correspondingly, that regional drivers influence ice out. These results also indicate that ice out dates for lakes from the region where records have not been kept can also be interpolated from these results. As the ice out record was coherent, further analysis was done for only Oromocto Lake on the basis of it having the longest ice out record. Cross-wavelet analysis was carried out between the ice out record and a variety of cyclic climate teleconnections and the sunspot record to identify which phenomena best explain the observed ice out trends. The most important observed contributors to ice out were the North Atlantic Oscillation (NAO) and the El Niño Southern Oscillation (ENSO), with observed periodicities at the interannual scale. At the decadal scale the Pacific Decadal Oscillation (PDO) and the 11-year solar cycle were the only patterns observed to significantly contribute to ice out.
format: application/pdf
format: text/html
creator: Carling R. Walsh
creator: R. Timothy Patterson
subject: Ecohydrology
subject: Environmental Impacts
subject: Spatial and Geographic Information Science
description: doi:10.7717/peerj.13741
publisher: PeerJ Inc.
rights: © 2022 Walsh and Patterson
abstract: The available ice out (the date of disappearance of ice from a water body) records were analyzed from four relatively closely spaced lakes in southwestern New Brunswick (Harvey, Oromocto, Skiff) and eastern Maine (West Grand Lake), with the longest set of available observations being for Oromocto Lake starting in 1876. Results of a coherence analysis carried out on the ice out data from the four lakes indicates that there is regional coherence and correspondingly, that regional drivers influence ice out. These results also indicate that ice out dates for lakes from the region where records have not been kept can also be interpolated from these results. As the ice out record was coherent, further analysis was done for only Oromocto Lake on the basis of it having the longest ice out record. Cross-wavelet analysis was carried out between the ice out record and a variety of cyclic climate teleconnections and the sunspot record to identify which phenomena best explain the observed ice out trends. The most important observed contributors to ice out were the North Atlantic Oscillation (NAO) and the El Niño Southern Oscillation (ENSO), with observed periodicities at the interannual scale. At the decadal scale the Pacific Decadal Oscillation (PDO) and the 11-year solar cycle were the only patterns observed to significantly contribute to ice out.
bibliographic citation: Walsh et al. (2022) Regional impact of large-scale climate oscillations on ice out variability in New Brunswick and Maine. PeerJ 10:e13741 https://doi.org/10.7717/peerj.13741
date submitted: 2022-03-21
date accepted: 2022-06-26
issued: 2022-08-18
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Walsh
  given name: Carling R.
author list: Agent
  family name: Patterson
  given name: R. Timothy
doi: 10.7717/peerj.13741
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-08-18
copyright: ©2022 Walsh and Patterson
attribution name: Walsh and Patterson

Identifying important ecosystem service areas based on distributions of ecosystem services in the Beijing–Tianjin–Hebei region, China
type: item
type: AcademicArticle
description: Water conservation, soil conservation, biodiversity importance, and sandstorm prevention are important ecosystem services (ES) and the core challenges to sustainable economic and societal development in the Beijing–Tianjin–Hebei (BTH) region. Using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model and observation data, we identified high-value ES areas in the BTH region. The high-value ES areas were mainly found in the northern and southwestern parts of the region, like the Yanshan Mountain Range and the Taihang Mountain Range. The ecosystem in the northern mountains is dominated by forest and grassland, and generally provides more valuable ES than does the eastern agricultural plain. Greater species richness was mainly found in the northern mountains with low human activity intensity. Due to its proximity, the Yanshan Mountain Range is critical to the health of the local ecosystem of Beijing. High biodiversity was present in the vicinity of the national nature reserves. Compared with other regions of China, changes in the BTH region are highly intense. Reinforcement of biodiversity conservation and ecosystem restoration in areas with a high degree of ES in the BTH region are capable of effectively improving habitat quality and regional ES.
format: application/pdf
format: text/html
creator: Cuiyun Cheng
creator: Shuping Zhang
creator: Meichun Zhou
creator: Yanchun Du
creator: Chazhong Ge
subject: Ecology
subject: Ecosystem Science
subject: Natural Resource Management
subject: Spatial and Geographic Information Science
description: doi:10.7717/peerj.13881
publisher: PeerJ Inc.
rights: © 2022 Cheng et al.
abstract: Water conservation, soil conservation, biodiversity importance, and sandstorm prevention are important ecosystem services (ES) and the core challenges to sustainable economic and societal development in the Beijing–Tianjin–Hebei (BTH) region. Using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model and observation data, we identified high-value ES areas in the BTH region. The high-value ES areas were mainly found in the northern and southwestern parts of the region, like the Yanshan Mountain Range and the Taihang Mountain Range. The ecosystem in the northern mountains is dominated by forest and grassland, and generally provides more valuable ES than does the eastern agricultural plain. Greater species richness was mainly found in the northern mountains with low human activity intensity. Due to its proximity, the Yanshan Mountain Range is critical to the health of the local ecosystem of Beijing. High biodiversity was present in the vicinity of the national nature reserves. Compared with other regions of China, changes in the BTH region are highly intense. Reinforcement of biodiversity conservation and ecosystem restoration in areas with a high degree of ES in the BTH region are capable of effectively improving habitat quality and regional ES.
bibliographic citation: Cheng et al. (2022) Identifying important ecosystem service areas based on distributions of ecosystem services in the Beijing–Tianjin–Hebei region, China. PeerJ 10:e13881 https://doi.org/10.7717/peerj.13881
date submitted: 2021-12-17
date accepted: 2022-07-20
issued: 2022-08-18
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Cheng
  given name: Cuiyun
author list: Agent
  family name: Zhang
  given name: Shuping
author list: Agent
  family name: Zhou
  given name: Meichun
author list: Agent
  family name: Du
  given name: Yanchun
author list: Agent
  family name: Ge
  given name: Chazhong
doi: 10.7717/peerj.13881
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-08-18
copyright: ©2022 Cheng et al.
attribution name: Cheng et al.

A simple hierarchical model for heterogeneity in the evolutionary correlation on a phylogenetic tree
type: item
type: AcademicArticle
description: Numerous questions in phylogenetic comparative biology revolve around the correlated evolution of two or more phenotypic traits on a phylogeny. In many cases, it may be sufficient to assume a constant value for the evolutionary correlation between characters across all the clades and branches of the tree. Under other circumstances, however, it is desirable or necessary to account for the possibility that the evolutionary correlation differs through time or in different sections of the phylogeny. Here, we present a method designed to fit a hierarchical series of models for heterogeneity in the evolutionary rates and correlation of two quantitative traits on a phylogenetic tree. We apply the method to two datasets: one for different attributes of the buccal morphology in sunfishes (Centrarchidae); and a second for overall body length and relative body depth in rock- and non-rock-dwelling South American iguanian lizards. We also examine the performance of the method for parameter estimation and model selection using a small set of numerical simulations.
format: application/pdf
format: text/html
creator: Liam J. Revell
creator: Ken S. Toyama
creator: D. Luke Mahler
subject: Biodiversity
subject: Computational Biology
subject: Ecology
subject: Evolutionary Studies
subject: Zoology
description: doi:10.7717/peerj.13910
publisher: PeerJ Inc.
rights: © 2022 Revell et al.
abstract: Numerous questions in phylogenetic comparative biology revolve around the correlated evolution of two or more phenotypic traits on a phylogeny. In many cases, it may be sufficient to assume a constant value for the evolutionary correlation between characters across all the clades and branches of the tree. Under other circumstances, however, it is desirable or necessary to account for the possibility that the evolutionary correlation differs through time or in different sections of the phylogeny. Here, we present a method designed to fit a hierarchical series of models for heterogeneity in the evolutionary rates and correlation of two quantitative traits on a phylogenetic tree. We apply the method to two datasets: one for different attributes of the buccal morphology in sunfishes (Centrarchidae); and a second for overall body length and relative body depth in rock- and non-rock-dwelling South American iguanian lizards. We also examine the performance of the method for parameter estimation and model selection using a small set of numerical simulations.
bibliographic citation: Revell et al. (2022) A simple hierarchical model for heterogeneity in the evolutionary correlation on a phylogenetic tree. PeerJ 10:e13910 https://doi.org/10.7717/peerj.13910
date submitted: 2021-05-07
date accepted: 2022-07-27
issued: 2022-08-18
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Revell
  given name: Liam J.
author list: Agent
  family name: Toyama
  given name: Ken S.
author list: Agent
  family name: Mahler
  given name: D. Luke
doi: 10.7717/peerj.13910
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-08-18
copyright: © 2022 Revell et al.
attribution name: Revell et al.

Incorporating nonlinearity with generalized functional responses to simulate multiple predator effects
type: item
type: AcademicArticle
description: Predicting the combined effects of predators on shared prey has long been a focus of community ecology, yet quantitative predictions often fail. Failure to account for nonlinearity is one reason for this. Moreover, prey depletion in multiple predator effects (MPE) studies generates biased predictions in applications of common experimental and quantitative frameworks. Here, we explore additional sources of bias stemming from nonlinearities in prey predation risk. We show that in order to avoid bias, predictions about the combined effects of independent predators must account for nonlinear size-dependent risk for prey as well as changes in prey risk driven by nonlinear predator functional responses and depletion. Historical failure to account for biases introduced by well-known nonlinear processes that affect predation risk suggest that we may need to reevaluate the general conclusions that have been drawn about the ubiquity of emergent MPEs over the past three decades.
format: application/pdf
format: text/html
creator: Michael W. McCoy
creator: Elizabeth Hamman
creator: Molly Albecker
creator: Jeremy Wojdak
creator: James R. Vonesh
creator: Benjamin M. Bolker
subject: Biodiversity
subject: Ecology
subject: Zoology
subject: Statistics
description: doi:10.7717/peerj.13920
publisher: PeerJ Inc.
rights: © 2022 McCoy et al.
abstract: Predicting the combined effects of predators on shared prey has long been a focus of community ecology, yet quantitative predictions often fail. Failure to account for nonlinearity is one reason for this. Moreover, prey depletion in multiple predator effects (MPE) studies generates biased predictions in applications of common experimental and quantitative frameworks. Here, we explore additional sources of bias stemming from nonlinearities in prey predation risk. We show that in order to avoid bias, predictions about the combined effects of independent predators must account for nonlinear size-dependent risk for prey as well as changes in prey risk driven by nonlinear predator functional responses and depletion. Historical failure to account for biases introduced by well-known nonlinear processes that affect predation risk suggest that we may need to reevaluate the general conclusions that have been drawn about the ubiquity of emergent MPEs over the past three decades.
bibliographic citation: McCoy et al. (2022) Incorporating nonlinearity with generalized functional responses to simulate multiple predator effects. PeerJ 10:e13920 https://doi.org/10.7717/peerj.13920
date submitted: 2021-11-18
date accepted: 2022-07-28
issued: 2022-08-18
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: McCoy
  given name: Michael W.
author list: Agent
  family name: Hamman
  given name: Elizabeth
author list: Agent
  family name: Albecker
  given name: Molly
author list: Agent
  family name: Wojdak
  given name: Jeremy
author list: Agent
  family name: Vonesh
  given name: James R.
author list: Agent
  family name: Bolker
  given name: Benjamin M.
doi: 10.7717/peerj.13920
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-08-18
copyright: © 2022 McCoy et al.
attribution name: McCoy et al.

Enhancing georeferenced biodiversity inventories: automated information extraction from literature records reveal the gaps
type: item
type: AcademicArticle
description: We use natural language processing (NLP) to retrieve location data for cheilostome bryozoan species (text-mined occurrences (TMO)) in an automated procedure. We compare these results with data combined from two major public databases (DB): the Ocean Biodiversity Information System (OBIS), and the Global Biodiversity Information Facility (GBIF). Using DB and TMO data separately and in combination, we present latitudinal species richness curves using standard estimators (Chao2 and the Jackknife) and range-through approaches. Our combined DB and TMO species richness curves quantitatively document a bimodal global latitudinal diversity gradient for extant cheilostomes for the first time, with peaks in the temperate zones. A total of 79% of the georeferenced species we retrieved from TMO (N = 1,408) and DB (N = 4,549) are non-overlapping. Despite clear indications that global location data compiled for cheilostomes should be improved with concerted effort, our study supports the view that many marine latitudinal species richness patterns deviate from the canonical latitudinal diversity gradient (LDG). Moreover, combining online biodiversity databases with automated information retrieval from the published literature is a promising avenue for expanding taxon-location datasets.
format: application/pdf
format: text/html
creator: Bjørn Tore Kopperud
creator: Scott Lidgard
creator: Lee Hsiang Liow
subject: Biogeography
subject: Ecology
subject: Marine Biology
subject: Zoology
subject: Data Mining and Machine Learning
description: doi:10.7717/peerj.13921
publisher: PeerJ Inc.
rights: © 2022 Kopperud et al.
abstract: We use natural language processing (NLP) to retrieve location data for cheilostome bryozoan species (text-mined occurrences (TMO)) in an automated procedure. We compare these results with data combined from two major public databases (DB): the Ocean Biodiversity Information System (OBIS), and the Global Biodiversity Information Facility (GBIF). Using DB and TMO data separately and in combination, we present latitudinal species richness curves using standard estimators (Chao2 and the Jackknife) and range-through approaches. Our combined DB and TMO species richness curves quantitatively document a bimodal global latitudinal diversity gradient for extant cheilostomes for the first time, with peaks in the temperate zones. A total of 79% of the georeferenced species we retrieved from TMO (N = 1,408) and DB (N = 4,549) are non-overlapping. Despite clear indications that global location data compiled for cheilostomes should be improved with concerted effort, our study supports the view that many marine latitudinal species richness patterns deviate from the canonical latitudinal diversity gradient (LDG). Moreover, combining online biodiversity databases with automated information retrieval from the published literature is a promising avenue for expanding taxon-location datasets.
bibliographic citation: Kopperud et al. (2022) Enhancing georeferenced biodiversity inventories: automated information extraction from literature records reveal the gaps. PeerJ 10:e13921 https://doi.org/10.7717/peerj.13921
date submitted: 2022-04-22
date accepted: 2022-07-29
issued: 2022-08-18
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Kopperud
  given name: Bjørn Tore
author list: Agent
  family name: Lidgard
  given name: Scott
author list: Agent
  family name: Liow
  given name: Lee Hsiang
doi: 10.7717/peerj.13921
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-08-18
copyright: © 2022 Kopperud et al.
attribution name: Kopperud et al.

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