PeerJ
type: channel
link: https://peerj.com/articles/
description: Articles published in PeerJ
publisher: PeerJ Inc.
publication name: PeerJ
issn: 2167-8359
items: Longitudinal relations between non-suicidal self-injury and both depression and anxiety among senior high school adolescents: a cross-lagged panel network analysis
items: Licorice-root extract and potassium sorbate spray improved the yield and fruit quality and decreased heat stress of the ‘osteen’ mango cultivar
items: A novel gene silencing strategy based on tobacco rattle virus in Hibiscus mutabilis
items: Cross-cultural adaptation and psychometric properties of the Chinese version of the Intermittent Self-Catheterization Questionnaire (ISC-Q)
items: Genome-wide association study reveals genetic basis and candidate genes for chlorophyll content of leaves in maize (Zea mays L.)
items: Changes in the force-time curve during a repeat power ability assessment using loaded countermovement jumps
items: Acute psycho-physiological responses to submaximal constant-load cycling under intermittent hypoxia-hyperoxia vs. hypoxia-normoxia in young males
items: A method for evaluating sediment-induced macroinvertebrate community composition changes in Idaho streams
items: https://peerj.com/articles/18126
items: Impact of foam rolling with and without vibration on muscle oxidative metabolism and microvascular reactivity

Longitudinal relations between non-suicidal self-injury and both depression and anxiety among senior high school adolescents: a cross-lagged panel network analysis
type: item
type: AcademicArticle
description: Background Comorbidity between non-suicidal self-injury (NSSI) and depression and anxiety was common. In the framework of network theory, the examination of directionality and gender differences in longitudinal relationships at the symptom level made a significant contribution to the understanding of comorbidity. Therefore, this study employed cross-lagged panel network analysis to investigate the longitudinal interrelations between NSSI and depression and anxiety in Chinese adolescents, with a focus on gender differences. Method The study was conducted with a sample of 884 senior high school students (F/M: 481/403; mean age: 15.19 ± 0.48 years) from Jinchang City, Gansu Province, China. All respondents completed the Adolescent Non-Suicidal Self-Injury Assessment Questionnaire and the two subscales (depression and anxiety) of the Brief Symptom Inventory at two intervals. The data were estimated in R 4.2.0 to construct the cross-lagged panel network (CLPN). Results The CLPN results uncovered the gender differences. For boys, self-hitting and feeling scared emerged as central symptoms. Cutting predicted subsequent feelings of sadness (β = − 0.57), tension (β = − 0.52) and indifference (β = − 0.49), potentially serving as a bridge connecting NSSI to depression and anxiety. For girls, biting themselves and feeling scared were central symptoms. Carving and skin rubbing predicted subsequent feelings of indifference (β = − 0.31, −0.21), bridging NSSI to depression and anxiety. In addition, feeling scared emerged as the key bridge symptom connecting depression and anxiety. Conclusion The findings showed the gender-specific developmental characteristics of the directional relations between NSSI and depression and anxiety at the symptom level. They provided new insights into the comorbidity of NSSI and depression and anxiety, carrying important implications for the screening and intervention of adolescent NSSI.
format: application/pdf
format: text/html
creator: Haiyan Zhao
creator: Aibao Zhou
subject: Psychiatry and Psychology
subject: Public Health
subject: Mental Health
description: doi:10.7717/peerj.18134
publisher: PeerJ Inc.
rights: © 2024 Zhao and Zhou
abstract: Background Comorbidity between non-suicidal self-injury (NSSI) and depression and anxiety was common. In the framework of network theory, the examination of directionality and gender differences in longitudinal relationships at the symptom level made a significant contribution to the understanding of comorbidity. Therefore, this study employed cross-lagged panel network analysis to investigate the longitudinal interrelations between NSSI and depression and anxiety in Chinese adolescents, with a focus on gender differences. Method The study was conducted with a sample of 884 senior high school students (F/M: 481/403; mean age: 15.19 ± 0.48 years) from Jinchang City, Gansu Province, China. All respondents completed the Adolescent Non-Suicidal Self-Injury Assessment Questionnaire and the two subscales (depression and anxiety) of the Brief Symptom Inventory at two intervals. The data were estimated in R 4.2.0 to construct the cross-lagged panel network (CLPN). Results The CLPN results uncovered the gender differences. For boys, self-hitting and feeling scared emerged as central symptoms. Cutting predicted subsequent feelings of sadness (β = − 0.57), tension (β = − 0.52) and indifference (β = − 0.49), potentially serving as a bridge connecting NSSI to depression and anxiety. For girls, biting themselves and feeling scared were central symptoms. Carving and skin rubbing predicted subsequent feelings of indifference (β = − 0.31, −0.21), bridging NSSI to depression and anxiety. In addition, feeling scared emerged as the key bridge symptom connecting depression and anxiety. Conclusion The findings showed the gender-specific developmental characteristics of the directional relations between NSSI and depression and anxiety at the symptom level. They provided new insights into the comorbidity of NSSI and depression and anxiety, carrying important implications for the screening and intervention of adolescent NSSI.
bibliographic citation: Zhao et al. (2024) Longitudinal relations between non-suicidal self-injury and both depression and anxiety among senior high school adolescents: a cross-lagged panel network analysis. PeerJ 12:e18134 https://doi.org/10.7717/peerj.18134
date submitted: 2024-05-08
date accepted: 2024-08-29
issued: 2024-10-07
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Zhao
  given name: Haiyan
author list: Agent
  family name: Zhou
  given name: Aibao
doi: 10.7717/peerj.18134
volume: 12
issn: 2167-8359
publication name: PeerJ
publication date: 2024-10-07
copyright: ©2024 Zhao and Zhou
attribution name: Zhao and Zhou

Licorice-root extract and potassium sorbate spray improved the yield and fruit quality and decreased heat stress of the ‘osteen’ mango cultivar
type: item
type: AcademicArticle
description: Heat stress, low mango yields and inconsistent fruit quality are main challenges for growers. Recently, licorice-root extract (LRE) has been utilized to enhance vegetative growth, yield, and tolerance to abiotic stresses in fruit trees. Potassium sorbate (PS) also plays a significant role in various physiological and biochemical processes that are essential for mango growth, quality and abiotic stress tolerance. This work aimed to elucidate the effects of foliar sprays containing LRE and PS on the growth, yield, fruit quality, total chlorophyll content, and antioxidant enzymes of ‘Osteen’ mango trees. The mango trees were sprayed with LRE at 0, 2, 4 and 6 g/L and PS 0, 1, 2, and 3 mM. In mid-May, the mango trees were sprayed with a foliar solution, followed by monthly applications until 1 month before harvest. The results showed that trees with the highest concentration (6 g/L) of LRE exhibited the maximum leaf area, followed by those treated with the highest concentration (3 mM) of PS. Application of LRE and PS to Osteen mango trees significantly enhanced fruit weight, number of fruits per tree, yield (kg/tree), yield increasing%, and reduced number of sun-burned fruits compared to the control. LRE and PS foliar sprays to Osteen mango trees significantly enhanced fruit total soluble solids ˚Brix, TSS/acid ratio, and vitamin C content compared to the control. Meanwhile, total acidity percentage in ‘Osteen’ mango fruits significantly decreased after both LRE and PS foliar sprays. ‘Osteen’ mango trees showed a significant increase in leaf area, total chlorophyll content, total pigments, and leaf carotenoids. Our results suggest that foliar sprays containing LRE and PS significantly improved growth parameters, yield, fruit quality, antioxidant content, and total pigment concentration in ‘Osteen’ mango trees. Moreover, the most effective treatments were 3 mM PS and 6 g/L LRE. LRE and PS foliar spray caused a significant increase in yield percentage by 305.77%, and 232.4…
format: application/pdf
format: text/html
creator: Adel M. Al-Saif
creator: Haitham Ahmed El-khamissi
creator: Ibrahim Ahmed Elnaggar
creator: Mohammed Hamdy Farouk
creator: Magdy Abd El-Wahab Omar
creator: Abd El-wahed Naser Abd El-wahed
creator: Ashraf Ezzat Hamdy
creator: Hosny Fathy Abdel-Aziz
subject: Agricultural Science
subject: Biochemistry
subject: Plant Science
description: doi:10.7717/peerj.18200
publisher: PeerJ Inc.
rights: © 2024 Al-Saif et al.
abstract: Heat stress, low mango yields and inconsistent fruit quality are main challenges for growers. Recently, licorice-root extract (LRE) has been utilized to enhance vegetative growth, yield, and tolerance to abiotic stresses in fruit trees. Potassium sorbate (PS) also plays a significant role in various physiological and biochemical processes that are essential for mango growth, quality and abiotic stress tolerance. This work aimed to elucidate the effects of foliar sprays containing LRE and PS on the growth, yield, fruit quality, total chlorophyll content, and antioxidant enzymes of ‘Osteen’ mango trees. The mango trees were sprayed with LRE at 0, 2, 4 and 6 g/L and PS 0, 1, 2, and 3 mM. In mid-May, the mango trees were sprayed with a foliar solution, followed by monthly applications until 1 month before harvest. The results showed that trees with the highest concentration (6 g/L) of LRE exhibited the maximum leaf area, followed by those treated with the highest concentration (3 mM) of PS. Application of LRE and PS to Osteen mango trees significantly enhanced fruit weight, number of fruits per tree, yield (kg/tree), yield increasing%, and reduced number of sun-burned fruits compared to the control. LRE and PS foliar sprays to Osteen mango trees significantly enhanced fruit total soluble solids ˚Brix, TSS/acid ratio, and vitamin C content compared to the control. Meanwhile, total acidity percentage in ‘Osteen’ mango fruits significantly decreased after both LRE and PS foliar sprays. ‘Osteen’ mango trees showed a significant increase in leaf area, total chlorophyll content, total pigments, and leaf carotenoids. Our results suggest that foliar sprays containing LRE and PS significantly improved growth parameters, yield, fruit quality, antioxidant content, and total pigment concentration in ‘Osteen’ mango trees. Moreover, the most effective treatments were 3 mM PS and 6 g/L LRE. LRE and PS foliar spray caused a significant increase in yield percentage by 305.77%, and 232.4…
bibliographic citation: Al-Saif et al. (2024) Licorice-root extract and potassium sorbate spray improved the yield and fruit quality and decreased heat stress of the ‘osteen’ mango cultivar. PeerJ 12:e18200 https://doi.org/10.7717/peerj.18200
date submitted: 2024-05-22
date accepted: 2024-09-09
issued: 2024-10-07
is part of: PeerJ
license: https://creativecommons.org/licenses/by-nc/4.0
author list: Agent
  family name: Al-Saif
  given name: Adel M.
author list: Agent
  family name: El-khamissi
  given name: Haitham Ahmed
author list: Agent
  family name: Elnaggar
  given name: Ibrahim Ahmed
author list: Agent
  family name: Farouk
  given name: Mohammed Hamdy
author list: Agent
  family name: Omar
  given name: Magdy Abd El-Wahab
author list: Agent
  family name: Abd El-wahed
  given name: Abd El-wahed Naser
author list: Agent
  family name: Hamdy
  given name: Ashraf Ezzat
author list: Agent
  family name: Abdel-Aziz
  given name: Hosny Fathy
doi: 10.7717/peerj.18200
volume: 12
issn: 2167-8359
publication name: PeerJ
publication date: 2024-10-07
copyright: © 2024 Al-Saif et al.
attribution name: Al-Saif et al.

A novel gene silencing strategy based on tobacco rattle virus in Hibiscus mutabilis
type: item
type: AcademicArticle
description: Background Hibiscus mutabilis L. is a popular regional characteristic plant in China, cultivated for its attractive flower colors, extended bloom time, and medicinal properties. To enhance molecular breeding and gene function studies, we conducted transcriptome analysis and identified valuable genes in previous research. Nonetheless, the current inefficient and labor-intensive transformation techniques have hindered their applications. Virus-induced gene silencing (VIGS) provides a precise and effective strategy for post-transcriptional down-regulation of endogenous gene expression. Methods We investigated the performance of tobacco rattle virus (TRV) as a tool for targeting and silencing the gene encoding the protein involved in chloroplast development, cloroplastos alterados 1 (altered chloroplast; CLA1), of H. mutabilis through Agrobacterium tumefaciens-mediated infiltration. Results By effectively suppressing the CLA1 gene associated with chloroplast development in H. mutabilis via the TRV-VIGS system, we have illustrated the inaugural implementation of VIGS in this species. Quantitative RT-PCR proved that HmCLA1 expression in agro-infiltrated plants was lower than in the mock-infiltrated (mock) and the control (CK) plants. Phenotypic observations corroborated the albino phenotype in leaves following successful HmCLA1 silencing. Conclusions Our study showcases TRV-VIGS as a potential gene silencing tool for H. mutabilis, facilitating functional genomics studies and molecular breeding efforts in this species.
format: application/pdf
format: text/html
creator: Shiye Sang
creator: Yiqiong Liu
creator: Xiu Li
creator: Jiao Ma
creator: Xiaoli Liu
creator: Yuanzhao Yang
subject: Bioengineering
subject: Biotechnology
subject: Molecular Biology
subject: Plant Science
description: doi:10.7717/peerj.18211
publisher: PeerJ Inc.
rights: © 2024 Sang et al.
abstract: Background Hibiscus mutabilis L. is a popular regional characteristic plant in China, cultivated for its attractive flower colors, extended bloom time, and medicinal properties. To enhance molecular breeding and gene function studies, we conducted transcriptome analysis and identified valuable genes in previous research. Nonetheless, the current inefficient and labor-intensive transformation techniques have hindered their applications. Virus-induced gene silencing (VIGS) provides a precise and effective strategy for post-transcriptional down-regulation of endogenous gene expression. Methods We investigated the performance of tobacco rattle virus (TRV) as a tool for targeting and silencing the gene encoding the protein involved in chloroplast development, cloroplastos alterados 1 (altered chloroplast; CLA1), of H. mutabilis through Agrobacterium tumefaciens-mediated infiltration. Results By effectively suppressing the CLA1 gene associated with chloroplast development in H. mutabilis via the TRV-VIGS system, we have illustrated the inaugural implementation of VIGS in this species. Quantitative RT-PCR proved that HmCLA1 expression in agro-infiltrated plants was lower than in the mock-infiltrated (mock) and the control (CK) plants. Phenotypic observations corroborated the albino phenotype in leaves following successful HmCLA1 silencing. Conclusions Our study showcases TRV-VIGS as a potential gene silencing tool for H. mutabilis, facilitating functional genomics studies and molecular breeding efforts in this species.
bibliographic citation: Sang et al. (2024) A novel gene silencing strategy based on tobacco rattle virus in Hibiscus mutabilis. PeerJ 12:e18211 https://doi.org/10.7717/peerj.18211
date submitted: 2024-06-07
date accepted: 2024-09-10
issued: 2024-10-07
is part of: PeerJ
license: https://creativecommons.org/licenses/by-nc/4.0
author list: Agent
  family name: Sang
  given name: Shiye
author list: Agent
  family name: Liu
  given name: Yiqiong
author list: Agent
  family name: Li
  given name: Xiu
author list: Agent
  family name: Ma
  given name: Jiao
author list: Agent
  family name: Liu
  given name: Xiaoli
author list: Agent
  family name: Yang
  given name: Yuanzhao
doi: 10.7717/peerj.18211
volume: 12
issn: 2167-8359
publication name: PeerJ
publication date: 2024-10-07
copyright: © 2024 Sang et al.
attribution name: Sang et al.

Cross-cultural adaptation and psychometric properties of the Chinese version of the Intermittent Self-Catheterization Questionnaire (ISC-Q)
type: item
type: AcademicArticle
description: Background The intermittent self-catheterization questionnaire (ISC-Q) is a valid and reliable tool to assess the quality of life (QOL) in patients with neurogenic lower urinary tract dysfunction (NLUTD) who engage in ISC. The aim of this research is to culturally adapt the ISC-Q and evaluate its psychometric properties within the Chinese patient population. Methods The cross-sectional research was meticulously conducted in two pivotal stages: initially, the focus was on cross-cultural adaptation, followed by an extensive phase of psychometric testing. This comprehensive analysis involved 405 Chinese patients with NLUTD who use ISC. Various analyses, including evaluations of the floor and ceiling effects, item analysis, content validity, exploratory and confirmatory factor analysis (EFA and CFA), assessments of convergent, discriminant, and criterion validity. Additionally, Cronbach’s alpha was utilized to determine internal consistency, and test-retest reliability was measured using the intraclass correlation coefficient (ICC). Results No floor and ceiling effects were observed. The content validity index was 0.967. The EFA identified four factors, accounting for 64.953% of the total variance, and this four-factor structure was confirmed by the CFA. The fit indices in CFA were favorable, with χ2/df = 1.999, root mean square error of approximation = 0.070, comparative fit index = 0.916, Tucker–Lewis index = 0.900, goodness-of-fit index = 0.863, and incremental fit index = 0.917. The average variance extracted for the four factors ranged from 0.466 to 0.565, with composite reliability values ranging from 0.776 to 0.859. The ISC-Q showed a positive correlation with the intermittent self-catheterization acceptance questionnaire (r = 0.557, P < 0.001). The ICC overall Cronbach’s alpha coefficient for the questionnaire was 0.821, and the for test-retest reliability was 0.951 (95% CI [0.900–0.976] P < 0.001). Conclusion The validity and reliability of the Chinese version …
format: application/pdf
format: text/html
creator: Yingjie Hu
creator: Fengming Hao
creator: Ling Chen
creator: Ying Wang
creator: Laifu Wang
creator: Dan Wu
creator: Wei Ren
creator: Wenzhi Cai
subject: Nursing
subject: Urology
description: doi:10.7717/peerj.18226
publisher: PeerJ Inc.
rights: © 2024 Hu et al.
abstract: Background The intermittent self-catheterization questionnaire (ISC-Q) is a valid and reliable tool to assess the quality of life (QOL) in patients with neurogenic lower urinary tract dysfunction (NLUTD) who engage in ISC. The aim of this research is to culturally adapt the ISC-Q and evaluate its psychometric properties within the Chinese patient population. Methods The cross-sectional research was meticulously conducted in two pivotal stages: initially, the focus was on cross-cultural adaptation, followed by an extensive phase of psychometric testing. This comprehensive analysis involved 405 Chinese patients with NLUTD who use ISC. Various analyses, including evaluations of the floor and ceiling effects, item analysis, content validity, exploratory and confirmatory factor analysis (EFA and CFA), assessments of convergent, discriminant, and criterion validity. Additionally, Cronbach’s alpha was utilized to determine internal consistency, and test-retest reliability was measured using the intraclass correlation coefficient (ICC). Results No floor and ceiling effects were observed. The content validity index was 0.967. The EFA identified four factors, accounting for 64.953% of the total variance, and this four-factor structure was confirmed by the CFA. The fit indices in CFA were favorable, with χ2/df = 1.999, root mean square error of approximation = 0.070, comparative fit index = 0.916, Tucker–Lewis index = 0.900, goodness-of-fit index = 0.863, and incremental fit index = 0.917. The average variance extracted for the four factors ranged from 0.466 to 0.565, with composite reliability values ranging from 0.776 to 0.859. The ISC-Q showed a positive correlation with the intermittent self-catheterization acceptance questionnaire (r = 0.557, P < 0.001). The ICC overall Cronbach’s alpha coefficient for the questionnaire was 0.821, and the for test-retest reliability was 0.951 (95% CI [0.900–0.976] P < 0.001). Conclusion The validity and reliability of the Chinese version …
bibliographic citation: Hu et al. (2024) Cross-cultural adaptation and psychometric properties of the Chinese version of the Intermittent Self-Catheterization Questionnaire (ISC-Q). PeerJ 12:e18226 https://doi.org/10.7717/peerj.18226
date submitted: 2023-12-29
date accepted: 2024-09-12
issued: 2024-10-07
is part of: PeerJ
license: https://creativecommons.org/licenses/by-nc/4.0
author list: Agent
  family name: Hu
  given name: Yingjie
author list: Agent
  family name: Hao
  given name: Fengming
author list: Agent
  family name: Chen
  given name: Ling
author list: Agent
  family name: Wang
  given name: Ying
author list: Agent
  family name: Wang
  given name: Laifu
author list: Agent
  family name: Wu
  given name: Dan
author list: Agent
  family name: Ren
  given name: Wei
author list: Agent
  family name: Cai
  given name: Wenzhi
doi: 10.7717/peerj.18226
volume: 12
issn: 2167-8359
publication name: PeerJ
publication date: 2024-10-07
copyright: © 2024 Hu et al.
attribution name: Hu et al.

Genome-wide association study reveals genetic basis and candidate genes for chlorophyll content of leaves in maize (Zea mays L.)
type: item
type: AcademicArticle
description: The chlorophyll content (CC) directly affects photosynthesis, growth, and yield. However, the genetic basis of CC is still unclear in maize (Zea mays L.). Here, we conducted a genome-wide association study using mixed linear model for CC of the fifth leaves at seedling stage (CCFSS) and the ear leaves at filling stage (CCEFS) for 334 maize inbred lines. The heritability estimates for CCFSS and CCEFS, obtained via variance components analysis using the lme4 package in R, were 70.84% and 78.99%, respectively, indicating that the CC of leaves is primarily controlled by genetic factors. A total of 15 CC-related SNPs and 177 candidate genes were identified with a p-value < 4.49 × 10−5, which explained 4.98–7.59% of the phenotypic variation. Lines with more favorable gene variants showed higher CC. Meanwhile, Gene Ontology (GO) analysis implied that these candidate genes were probably related to chlorophyll biosynthesis. In addition, gene-based association analyses revealed that six variants in GRMZM2G037152, GRMZM5G816561, GRMZM2G324462, and GRMZM2G064657 genes were significantly (p-value < 0.01) correlated with CC, of which GRMZM2G064657 (encodes a phosphate transporter protein) and GRMZM5G816561 (encodes a cytochrome P450 protein) were specifically highly expressed in leaves tissues. Interestingly, these candidate genes were previously reported to involve in the regulation of the contents of chlorophyll in plants or Chlamydomonas. These results may contribute to the understanding of genetic basis and molecular mechanisms of maize CC and the selection of maize varieties with improved CC.
format: application/pdf
format: text/html
creator: Peng Liu
creator: Chenchaoyang Xiang
creator: Kai Liu
creator: Hong Yu
creator: Zhengqiao Liao
creator: Yaou Shen
creator: Lei Liu
creator: Langlang Ma
subject: Agricultural Science
subject: Bioinformatics
subject: Genetics
subject: Plant Science
description: doi:10.7717/peerj.18278
publisher: PeerJ Inc.
rights: © 2024 Liu et al.
abstract: The chlorophyll content (CC) directly affects photosynthesis, growth, and yield. However, the genetic basis of CC is still unclear in maize (Zea mays L.). Here, we conducted a genome-wide association study using mixed linear model for CC of the fifth leaves at seedling stage (CCFSS) and the ear leaves at filling stage (CCEFS) for 334 maize inbred lines. The heritability estimates for CCFSS and CCEFS, obtained via variance components analysis using the lme4 package in R, were 70.84% and 78.99%, respectively, indicating that the CC of leaves is primarily controlled by genetic factors. A total of 15 CC-related SNPs and 177 candidate genes were identified with a p-value < 4.49 × 10−5, which explained 4.98–7.59% of the phenotypic variation. Lines with more favorable gene variants showed higher CC. Meanwhile, Gene Ontology (GO) analysis implied that these candidate genes were probably related to chlorophyll biosynthesis. In addition, gene-based association analyses revealed that six variants in GRMZM2G037152, GRMZM5G816561, GRMZM2G324462, and GRMZM2G064657 genes were significantly (p-value < 0.01) correlated with CC, of which GRMZM2G064657 (encodes a phosphate transporter protein) and GRMZM5G816561 (encodes a cytochrome P450 protein) were specifically highly expressed in leaves tissues. Interestingly, these candidate genes were previously reported to involve in the regulation of the contents of chlorophyll in plants or Chlamydomonas. These results may contribute to the understanding of genetic basis and molecular mechanisms of maize CC and the selection of maize varieties with improved CC.
bibliographic citation: Liu et al. (2024) Genome-wide association study reveals genetic basis and candidate genes for chlorophyll content of leaves in maize (Zea mays L.). PeerJ 12:e18278 https://doi.org/10.7717/peerj.18278
date submitted: 2024-07-24
date accepted: 2024-09-18
issued: 2024-10-07
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Liu
  given name: Peng
author list: Agent
  family name: Xiang
  given name: Chenchaoyang
author list: Agent
  family name: Liu
  given name: Kai
author list: Agent
  family name: Yu
  given name: Hong
author list: Agent
  family name: Liao
  given name: Zhengqiao
author list: Agent
  family name: Shen
  given name: Yaou
author list: Agent
  family name: Liu
  given name: Lei
author list: Agent
  family name: Ma
  given name: Langlang
doi: 10.7717/peerj.18278
volume: 12
issn: 2167-8359
publication name: PeerJ
publication date: 2024-10-07
copyright: © 2024 Liu et al.
attribution name: Liu et al.

Changes in the force-time curve during a repeat power ability assessment using loaded countermovement jumps
type: item
type: AcademicArticle
description: Background Repeat power ability (RPA) assessments traditionally use discrete variables, such as peak power output, to quantify the change in performance across a series of jumps. Rather than using a discrete variable, the analysis of the entire force-time curve may provide additional insight into RPA performance. The aims of this study were to (1) analyse changes in the force-time curve recorded during an RPA assessment using statistical parametric mapping (SPM) and (2) compare the differences in the force-time curve between participants with low and high RPA scores, as quantified by traditional analysis. Materials and Methods Eleven well-trained field hockey players performed an RPA assessment consisting of 20 loaded countermovement jumps with a 30% one repetition maximum half squat load (LCMJ20). Mean force-time series data was normalized to 100% of the movement duration and analysed using SPM. Peak power output for each jump was also derived from the force-time data and a percent decrement score calculated for jumps 2 to 19 (RPA%dec). An SPM one-way ANOVA with significance accepted at α = 0.05, was used to identify the change in the force-time curve over three distinct series of jumps across the LCMJ20 (series 1 = jumps 2–5, series 2 = jumps 9–12 and series 3 = jumps 16–19). A secondary analysis, using an independent T-test with significance accepted at p < 0.001, was also used to identify differences in the force-time curve between participants with low and high RPA%dec. Results Propulsive forces were significantly lower (p < 0.001) between 74–98% of the movement compared to 0–73% for changes recorded during the LCMJ20. Post hoc analysis identified the greatest differences to occur between jump series 1 and jump series 2 (p < 0.001) at 70–98% of the movement and between jump series 1 and jump series 3 (p < 0.001) at 86–99% of the movement. No significant differences were found between jump series 2 and jump series 3. Significant differences (p < 0.001) in both t…
format: application/pdf
format: text/html
creator: Alex O. Natera
creator: Steven Hughes
creator: Dale W. Chapman
creator: Neil D. Chapman
creator: Justin W.L. Keogh
subject: Anatomy and Physiology
subject: Kinesiology
subject: Biomechanics
subject: Sports Medicine
description: doi:10.7717/peerj.17971
publisher: PeerJ Inc.
rights: © 2024 Natera et al.
abstract: Background Repeat power ability (RPA) assessments traditionally use discrete variables, such as peak power output, to quantify the change in performance across a series of jumps. Rather than using a discrete variable, the analysis of the entire force-time curve may provide additional insight into RPA performance. The aims of this study were to (1) analyse changes in the force-time curve recorded during an RPA assessment using statistical parametric mapping (SPM) and (2) compare the differences in the force-time curve between participants with low and high RPA scores, as quantified by traditional analysis. Materials and Methods Eleven well-trained field hockey players performed an RPA assessment consisting of 20 loaded countermovement jumps with a 30% one repetition maximum half squat load (LCMJ20). Mean force-time series data was normalized to 100% of the movement duration and analysed using SPM. Peak power output for each jump was also derived from the force-time data and a percent decrement score calculated for jumps 2 to 19 (RPA%dec). An SPM one-way ANOVA with significance accepted at α = 0.05, was used to identify the change in the force-time curve over three distinct series of jumps across the LCMJ20 (series 1 = jumps 2–5, series 2 = jumps 9–12 and series 3 = jumps 16–19). A secondary analysis, using an independent T-test with significance accepted at p < 0.001, was also used to identify differences in the force-time curve between participants with low and high RPA%dec. Results Propulsive forces were significantly lower (p < 0.001) between 74–98% of the movement compared to 0–73% for changes recorded during the LCMJ20. Post hoc analysis identified the greatest differences to occur between jump series 1 and jump series 2 (p < 0.001) at 70–98% of the movement and between jump series 1 and jump series 3 (p < 0.001) at 86–99% of the movement. No significant differences were found between jump series 2 and jump series 3. Significant differences (p < 0.001) in both t…
bibliographic citation: Natera et al. (2024) Changes in the force-time curve during a repeat power ability assessment using loaded countermovement jumps. PeerJ 12:e17971 https://doi.org/10.7717/peerj.17971
date submitted: 2024-02-09
date accepted: 2024-08-05
issued: 2024-10-04
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Natera
  given name: Alex O.
author list: Agent
  family name: Hughes
  given name: Steven
author list: Agent
  family name: Chapman
  given name: Dale W.
author list: Agent
  family name: Chapman
  given name: Neil D.
author list: Agent
  family name: Keogh
  given name: Justin W.L.
doi: 10.7717/peerj.17971
volume: 12
issn: 2167-8359
publication name: PeerJ
publication date: 2024-10-04
copyright: ©2024 Natera et al.
attribution name: Natera et al.

Acute psycho-physiological responses to submaximal constant-load cycling under intermittent hypoxia-hyperoxia vs. hypoxia-normoxia in young males
type: item
type: AcademicArticle
description: Background Hypoxia and hyperoxia can affect the acute psycho-physiological response to exercise. Recording various perceptual responses to exercise is of particular importance for investigating behavioral changes to physical activity, given that the perception of exercise-induced pain, discomfort or unpleasure, and a low level of exercise enjoyment are commonly associated with a low adherence to physical activity. Therefore, this study aimed to compare the acute perceptual and physiological responses to aerobic exercise under intermittent hypoxia-hyperoxia (IHHT), hypoxia-normoxia (IHT), and sustained normoxia (NOR) in young, recreational active, healthy males. Methods Using a randomized, single-blinded, crossover design, 15 males (age: 24.5 ± 4.2 yrs) performed 40 min of submaximal constant-load cycling (at 60% peak oxygen uptake, 80 rpm) under IHHT (5 × 4 min hypoxia and hyperoxia), IHT (5 × 4 min hypoxia and normoxia), and NOR. Inspiratory fraction of oxygen during hypoxia and hyperoxia was set to 14% and 30%, respectively. Heart rate (HR), total hemoglobin (tHb) and muscle oxygen saturation (SmO2) of the right vastus lateralis muscle were continuously recorded during cycling. Participants’ peripheral oxygen saturation (SpO2) and perceptual responses (i.e., perceived motor fatigue, effort perception, perceived physical strain, affective valence, arousal, motivation to exercise, and conflict to continue exercise) were surveyed prior, during (every 4 min), and after cycling. Prior to and after exercise, peripheral blood lactate concentration (BLC) was determined. Exercise enjoyment was ascertained after cycling. For statistical analysis, repeated measures analyses of variance were conducted. Results No differences in the acute perceptual responses were found between conditions (p ≥ 0.059, ηp2 ≤ 0.18), while the physiological responses differed. Accordingly, SpO2 was higher during the hyperoxic periods during the IHHT compared to the normoxic periods during the IHT …
format: application/pdf
format: text/html
creator: Tom Behrendt
creator: Robert Bielitzki
creator: Martin Behrens
creator: Lina-Marie Jahns
creator: Malte Boersma
creator: Lutz Schega
subject: Anatomy and Physiology
subject: Psychiatry and Psychology
subject: Metabolic Sciences
subject: Sports Medicine
description: doi:10.7717/peerj.18027
publisher: PeerJ Inc.
rights: © 2024 Behrendt et al.
abstract: Background Hypoxia and hyperoxia can affect the acute psycho-physiological response to exercise. Recording various perceptual responses to exercise is of particular importance for investigating behavioral changes to physical activity, given that the perception of exercise-induced pain, discomfort or unpleasure, and a low level of exercise enjoyment are commonly associated with a low adherence to physical activity. Therefore, this study aimed to compare the acute perceptual and physiological responses to aerobic exercise under intermittent hypoxia-hyperoxia (IHHT), hypoxia-normoxia (IHT), and sustained normoxia (NOR) in young, recreational active, healthy males. Methods Using a randomized, single-blinded, crossover design, 15 males (age: 24.5 ± 4.2 yrs) performed 40 min of submaximal constant-load cycling (at 60% peak oxygen uptake, 80 rpm) under IHHT (5 × 4 min hypoxia and hyperoxia), IHT (5 × 4 min hypoxia and normoxia), and NOR. Inspiratory fraction of oxygen during hypoxia and hyperoxia was set to 14% and 30%, respectively. Heart rate (HR), total hemoglobin (tHb) and muscle oxygen saturation (SmO2) of the right vastus lateralis muscle were continuously recorded during cycling. Participants’ peripheral oxygen saturation (SpO2) and perceptual responses (i.e., perceived motor fatigue, effort perception, perceived physical strain, affective valence, arousal, motivation to exercise, and conflict to continue exercise) were surveyed prior, during (every 4 min), and after cycling. Prior to and after exercise, peripheral blood lactate concentration (BLC) was determined. Exercise enjoyment was ascertained after cycling. For statistical analysis, repeated measures analyses of variance were conducted. Results No differences in the acute perceptual responses were found between conditions (p ≥ 0.059, ηp2 ≤ 0.18), while the physiological responses differed. Accordingly, SpO2 was higher during the hyperoxic periods during the IHHT compared to the normoxic periods during the IHT …
bibliographic citation: Behrendt et al. (2024) Acute psycho-physiological responses to submaximal constant-load cycling under intermittent hypoxia-hyperoxia vs. hypoxia-normoxia in young males. PeerJ 12:e18027 https://doi.org/10.7717/peerj.18027
date submitted: 2024-03-22
date accepted: 2024-08-12
issued: 2024-10-04
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Behrendt
  given name: Tom
author list: Agent
  family name: Bielitzki
  given name: Robert
author list: Agent
  family name: Behrens
  given name: Martin
author list: Agent
  family name: Jahns
  given name: Lina-Marie
author list: Agent
  family name: Boersma
  given name: Malte
author list: Agent
  family name: Schega
  given name: Lutz
doi: 10.7717/peerj.18027
volume: 12
issn: 2167-8359
publication name: PeerJ
publication date: 2024-10-04
copyright: © 2024 Behrendt et al.
attribution name: Behrendt et al.

A method for evaluating sediment-induced macroinvertebrate community composition changes in Idaho streams
type: item
type: AcademicArticle
description: Human activities can increase sediment delivery to streams, changing the composition, distribution, and abundance of stream aquatic life. Few U.S. states have numeric water quality standards for streambed sediment under the Clean Water Act, so managers often need to develop local application-specific benchmarks. This study developed stream surface fine sediment <2 mm (sand and fines, SF) and macroinvertebrate fine sediment biotic index (FSBI) benchmarks and an application framework to test for sediment-induced macroinvertebrate community composition changes in 1st–4th order Idaho streams. FSBI reference benchmarks were calculated as the 25th percentile FSBI value among reference sites within three ecoregion-based site classes. Two approaches were used to develop SF benchmarks. Quantile regression was used to define reach-specific SF benchmarks representing an upper bound value expected under reference conditions. In addition, logistic regression was used to predict SF values with 50% and 75% probability that FSBI is worse than reference within each stream order and site class. The strength of association between SF benchmarks and macroinvertebrate community condition was evaluated by calculating relative risk using multiple datasets and examining responses of multiple macroinvertebrate indicators to SF benchmark status. SF reference benchmarks generally had stronger associations with poor macroinvertebrate condition than SF stressor-response benchmarks. Across datasets and macroinvertebrate indicators, poor macroinvertebrate condition was 1.8–3 times more likely when SF reference benchmarks were exceeded than when achieved. We propose rating the strength of evidence for a surface fine sediment-induced macroinvertebrate community composition change at the sample event scale as ‘unlikely’ if both SF and FSBI reference benchmarks are achieved, having ‘mixed evidence’ if only one reference benchmark is achieved, and ‘likely’ if both reference benchmarks are not achieved…
format: application/pdf
format: text/html
creator: Jason Williams
creator: James Efta
subject: Ecology
subject: Freshwater Biology
subject: Natural Resource Management
subject: Environmental Impacts
description: doi:10.7717/peerj.18060
publisher: PeerJ Inc.
rights: © 2024 Williams and Efta
abstract: Human activities can increase sediment delivery to streams, changing the composition, distribution, and abundance of stream aquatic life. Few U.S. states have numeric water quality standards for streambed sediment under the Clean Water Act, so managers often need to develop local application-specific benchmarks. This study developed stream surface fine sediment <2 mm (sand and fines, SF) and macroinvertebrate fine sediment biotic index (FSBI) benchmarks and an application framework to test for sediment-induced macroinvertebrate community composition changes in 1st–4th order Idaho streams. FSBI reference benchmarks were calculated as the 25th percentile FSBI value among reference sites within three ecoregion-based site classes. Two approaches were used to develop SF benchmarks. Quantile regression was used to define reach-specific SF benchmarks representing an upper bound value expected under reference conditions. In addition, logistic regression was used to predict SF values with 50% and 75% probability that FSBI is worse than reference within each stream order and site class. The strength of association between SF benchmarks and macroinvertebrate community condition was evaluated by calculating relative risk using multiple datasets and examining responses of multiple macroinvertebrate indicators to SF benchmark status. SF reference benchmarks generally had stronger associations with poor macroinvertebrate condition than SF stressor-response benchmarks. Across datasets and macroinvertebrate indicators, poor macroinvertebrate condition was 1.8–3 times more likely when SF reference benchmarks were exceeded than when achieved. We propose rating the strength of evidence for a surface fine sediment-induced macroinvertebrate community composition change at the sample event scale as ‘unlikely’ if both SF and FSBI reference benchmarks are achieved, having ‘mixed evidence’ if only one reference benchmark is achieved, and ‘likely’ if both reference benchmarks are not achieved…
bibliographic citation: Williams et al. (2024) A method for evaluating sediment-induced macroinvertebrate community composition changes in Idaho streams. PeerJ 12:e18060 https://doi.org/10.7717/peerj.18060
date submitted: 2024-06-18
date accepted: 2024-08-17
issued: 2024-10-04
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Williams
  given name: Jason
author list: Agent
  family name: Efta
  given name: James
doi: 10.7717/peerj.18060
volume: 12
issn: 2167-8359
publication name: PeerJ
publication date: 2024-10-04
copyright: © 2024 Williams and Efta
attribution name: Williams and Efta

https://peerj.com/articles/18126
type: item
type: AcademicArticle
title: Beyond graft function impairment after liver transplantation: the prolonged cold ischemia time impact on recurrence of hepatocellular carcinoma after liver transplantation—a single-center retrospective study
description: Purpose Hepatocellular carcinoma (HCC) is one of the malignant tumors responsible for high mortality and recurrence rates. Although liver transplantation (LT) is an effective treatment option for HCC, ischemia-reperfusion injury (IRI) is a contributor to HCC recurrence after LT. Moreover, prolonged cold ischemia time (CIT) is a risk factor for IRI during LT, and there is insufficient clinical evidence regarding the impact of CIT on HCC recurrence after LT. Patients and Methods This retrospective study analyzed 420 patients who underwent LT for HCC between February 2015 and November 2020 at The First Affiliated Hospital, Sun Yat-sen University. The duration of CIT was defined as the time from clamping of the donor aorta until portal reperfusion. Results A total of 133 patients (31.7%) experienced tumor recurrence after LT, and CIT > 568 min was the independent risk factor for HCC recurrence (OR, 2.406; 95% CI [1.371–4.220]; p = 0.002). Multivariate Cox’s regression analysis revealed that the recipients’ gender, exceeding Milan criteria, poor differentiation, and alpha-fetoprotein (AFP) ≥400 ng/ml in CIT > 568 min group were independent risk factors for disease-free survival. The peak 7-day postoperative alanine aminotransferase (ALT) level (p < 0.001), the peak 7-day postoperative aspartate aminotransferase (AST) level (p < 0.001), the peak 7-day postoperative peak total bilirubin (TBIL) level (p = 0.012), and the incidence of early allograft dysfunction (EAD) (p = 0.006) were significantly higher in the CIT > 568 min group compared to the CIT ≤ 568 min group. Moreover, the amount of fresh frozen plasma (FFP) infusion during the operation increased (p = 0.02), and the time of mechanical ventilation postoperative was longer (p = 0.045). Conclusion An effective strategy to improve the prognosis is to reduce CIT; this strategy lowers the recurrence of HCC in patients undergoing LT, especially those within the Milan criteria.
format: application/pdf
format: text/html
creator: Jia Yu
creator: Tang Yunhua
creator: Yiwen Guo
creator: Yuqi Dong
creator: Jin long Gong
creator: Tielong Wang
creator: Zhitao Chen
creator: Maogen Chen
creator: Weiqiang Ju
creator: Xiaoshun He
subject: Gastroenterology and Hepatology
subject: Oncology
subject: Surgery and Surgical Specialties
description: doi:10.7717/peerj.18126
publisher: PeerJ Inc.
rights: © 2024 Yu et al.
abstract: Purpose Hepatocellular carcinoma (HCC) is one of the malignant tumors responsible for high mortality and recurrence rates. Although liver transplantation (LT) is an effective treatment option for HCC, ischemia-reperfusion injury (IRI) is a contributor to HCC recurrence after LT. Moreover, prolonged cold ischemia time (CIT) is a risk factor for IRI during LT, and there is insufficient clinical evidence regarding the impact of CIT on HCC recurrence after LT. Patients and Methods This retrospective study analyzed 420 patients who underwent LT for HCC between February 2015 and November 2020 at The First Affiliated Hospital, Sun Yat-sen University. The duration of CIT was defined as the time from clamping of the donor aorta until portal reperfusion. Results A total of 133 patients (31.7%) experienced tumor recurrence after LT, and CIT > 568 min was the independent risk factor for HCC recurrence (OR, 2.406; 95% CI [1.371–4.220]; p = 0.002). Multivariate Cox’s regression analysis revealed that the recipients’ gender, exceeding Milan criteria, poor differentiation, and alpha-fetoprotein (AFP) ≥400 ng/ml in CIT > 568 min group were independent risk factors for disease-free survival. The peak 7-day postoperative alanine aminotransferase (ALT) level (p < 0.001), the peak 7-day postoperative aspartate aminotransferase (AST) level (p < 0.001), the peak 7-day postoperative peak total bilirubin (TBIL) level (p = 0.012), and the incidence of early allograft dysfunction (EAD) (p = 0.006) were significantly higher in the CIT > 568 min group compared to the CIT ≤ 568 min group. Moreover, the amount of fresh frozen plasma (FFP) infusion during the operation increased (p = 0.02), and the time of mechanical ventilation postoperative was longer (p = 0.045). Conclusion An effective strategy to improve the prognosis is to reduce CIT; this strategy lowers the recurrence of HCC in patients undergoing LT, especially those within the Milan criteria.
bibliographic citation: Yu et al. (2024) Beyond graft function impairment after liver transplantation: the prolonged cold ischemia time impact on recurrence of hepatocellular carcinoma after liver transplantation—a single-center retrospective study. PeerJ 12:e18126 https://doi.org/10.7717/peerj.18126
date submitted: 2023-03-15
date accepted: 2024-08-28
issued: 2024-10-04
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Yu
  given name: Jia
author list: Agent
  family name: Yunhua
  given name: Tang
author list: Agent
  family name: Guo
  given name: Yiwen
author list: Agent
  family name: Dong
  given name: Yuqi
author list: Agent
  family name: Gong
  given name: Jin long
author list: Agent
  family name: Wang
  given name: Tielong
author list: Agent
  family name: Chen
  given name: Zhitao
author list: Agent
  family name: Chen
  given name: Maogen
author list: Agent
  family name: Ju
  given name: Weiqiang
author list: Agent
  family name: He
  given name: Xiaoshun
doi: 10.7717/peerj.18126
volume: 12
issn: 2167-8359
publication name: PeerJ
publication date: 2024-10-04
copyright: ©2024 Yu et al.
attribution name: Yu et al.

Impact of foam rolling with and without vibration on muscle oxidative metabolism and microvascular reactivity
type: item
type: AcademicArticle
description: Background and Purpose There is a growing interest in use vibration foam rolling as a warm up and recovery tool. However, whether vibration foam rolling offers additional benefits to traditional foam rolling is unclear. The current study aims to compare the effects of acute foam rolling, with and without vibration, on skeletal muscle metabolism and microvascular reactivity. Methods Fifteen physically active young males were tested on two different days, with gastrocnemius muscle microvascular function assessed using near-infrared spectroscopy coupled with the post-occlusive reactive hyperemia technique, before and after foam rolling, performed with or without vibration. The slope of tissue saturation index (TSI) decrease during occlusion between 120 s to 150 s (TSI occlusion slope) was assessed for muscle metabolic rate. Three commonly used microvascular function indexes, including the first10s TSI slope after occlusion (TSI10), time for TSI to reach half of peak magnitude (TSI1/2), and TSI peak reactive hyperemia, were also assessed. Results None of the measured indexes showed significance for interaction or method (all p > 0.05). However, there was a main effect for time for TSI occlusion slope, TSI1/2, and TSI peak reactive hyperemia (p = 0.005, 0.034 and 0.046, respectively). No main effect for time for TSI10 was detected (p = 0.963). Conclusions The application of foam rolling can decrease muscle metabolism, and may improve some aspects of muscle microvascular function. However, vibration foam rolling does not seem to offer any additional benefits compared to traditional foam rolling alone.
format: application/pdf
format: text/html
creator: Haizhen Huang
creator: Bin Leng
creator: Chuan Zhang
subject: Anatomy and Physiology
subject: Kinesiology
subject: Biomechanics
subject: Sports Injury
subject: Sports Medicine
description: doi:10.7717/peerj.18180
publisher: PeerJ Inc.
rights: © 2024 Huang et al.
abstract: Background and Purpose There is a growing interest in use vibration foam rolling as a warm up and recovery tool. However, whether vibration foam rolling offers additional benefits to traditional foam rolling is unclear. The current study aims to compare the effects of acute foam rolling, with and without vibration, on skeletal muscle metabolism and microvascular reactivity. Methods Fifteen physically active young males were tested on two different days, with gastrocnemius muscle microvascular function assessed using near-infrared spectroscopy coupled with the post-occlusive reactive hyperemia technique, before and after foam rolling, performed with or without vibration. The slope of tissue saturation index (TSI) decrease during occlusion between 120 s to 150 s (TSI occlusion slope) was assessed for muscle metabolic rate. Three commonly used microvascular function indexes, including the first10s TSI slope after occlusion (TSI10), time for TSI to reach half of peak magnitude (TSI1/2), and TSI peak reactive hyperemia, were also assessed. Results None of the measured indexes showed significance for interaction or method (all p > 0.05). However, there was a main effect for time for TSI occlusion slope, TSI1/2, and TSI peak reactive hyperemia (p = 0.005, 0.034 and 0.046, respectively). No main effect for time for TSI10 was detected (p = 0.963). Conclusions The application of foam rolling can decrease muscle metabolism, and may improve some aspects of muscle microvascular function. However, vibration foam rolling does not seem to offer any additional benefits compared to traditional foam rolling alone.
bibliographic citation: Huang et al. (2024) Impact of foam rolling with and without vibration on muscle oxidative metabolism and microvascular reactivity. PeerJ 12:e18180 https://doi.org/10.7717/peerj.18180
date submitted: 2024-07-10
date accepted: 2024-09-04
issued: 2024-10-04
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Huang
  given name: Haizhen
author list: Agent
  family name: Leng
  given name: Bin
author list: Agent
  family name: Zhang
  given name: Chuan
doi: 10.7717/peerj.18180
volume: 12
issn: 2167-8359
publication name: PeerJ
publication date: 2024-10-04
copyright: ©2024 Huang et al.
attribution name: Huang et al.

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