PeerJ
type: channel
link: https://peerj.com/articles/
description: Articles published in PeerJ
publisher: PeerJ Inc.
publication name: PeerJ
issn: 2167-8359
items: Genome-wide identification and functional analysis of class III peroxidases in Gossypium hirsutum
items: Recent advances in methods for in situ root phenotyping
items: Genetic diversity of enterotoxigenic Bacillus cereus strains in coriander in southwestern Mexico
items: Manipulation of light quality is an effective tool to regulate photosynthetic capacity and fruit antioxidant properties of Solanum lycopersicum L. cv. ‘Microtom’ in a controlled environment
items: Spatial distribution of soil nutrients and evaluation of cultivated land in Xuwen county
items: Soil organic carbon and nitrogen storage under a wheat (Triticum aestivum L.)—maize (Zea mays L.) cropping system in northern China was modified by nitrogen application rates
items: Electromyographic analysis of the serratus anterior and upper trapezius in closed kinetic chain exercises performed on different unstable support surfaces: a systematic review and meta-analysis
items: Thrombocytopenia and increased risk of adverse outcome in COVID-19 patients
items: Influence of Nordic walking with poles with an integrated resistance shock absorber on carbohydrate and lipid metabolic indices and white blood cell subpopulations in postmenopausal women
items: Taxonomic and functional nematode diversity in Maldivian coral degradation zones: patterns across reef typologies and depths

Genome-wide identification and functional analysis of class III peroxidases in Gossypium hirsutum
type: item
type: AcademicArticle
description: Class III peroxidase (PRX) genes play essential roles in various processes, such as auxin catabolism, removal of H2O2, crosslinking cell wall components, and response to biotic and abiotic stresses. In this study, we identified 166, 78 and 89 PRX genes from G. hirsutum, G. arboretum and G. raimondii, respectively. These PRX genes were classified into seven subfamilies based on phylogenetic tree analysis and the classification of PRX genes in Arabidopsis. Segmental duplication and purifying selection were the major factors driving the evolution of GhPRXs. GO and KEGG enrichment analysis revealed that GhPRX genes were mainly associated with responding to oxidative stresses, peroxidase activities and phenylpropanoid biosynthesis pathways. Transcriptome data analysis showed that GhPRX genes expression were significantly different in microspore development between the sterility line-JinA and the maintainer line MB177. We confirmed the up-regulation of GhPRX107 and down-regulation of GhPRX128 in the sterile line compared to its maintainer line using qRT-PCR, suggesting their roles in pollen fertility. In addition, silencing GhPRX107 in cotton showed a significant decrease of the reactive oxygen species (ROS) levels of microsporocyte stage anthers compared to control. Overexpressing GhPRX107 in Arabidopsis significantly increased the ROS levels of anthers compared to wild type. In conclusion, we identified GhPRX107 as a determinant of ROS levels in anther. This work sets a foundation for PRX studies in pollen development.
format: application/pdf
format: text/html
creator: Yi Chen
creator: Jiajia Feng
creator: Yunfang Qu
creator: Jinlong Zhang
creator: Li Zhang
creator: Dong Liang
creator: Yujie Yang
creator: Jinling Huang
subject: Agricultural Science
subject: Bioinformatics
subject: Genomics
subject: Molecular Biology
subject: Plant Science
description: doi:10.7717/peerj.13635
publisher: PeerJ Inc.
rights: © 2022 Chen et al.
abstract: Class III peroxidase (PRX) genes play essential roles in various processes, such as auxin catabolism, removal of H2O2, crosslinking cell wall components, and response to biotic and abiotic stresses. In this study, we identified 166, 78 and 89 PRX genes from G. hirsutum, G. arboretum and G. raimondii, respectively. These PRX genes were classified into seven subfamilies based on phylogenetic tree analysis and the classification of PRX genes in Arabidopsis. Segmental duplication and purifying selection were the major factors driving the evolution of GhPRXs. GO and KEGG enrichment analysis revealed that GhPRX genes were mainly associated with responding to oxidative stresses, peroxidase activities and phenylpropanoid biosynthesis pathways. Transcriptome data analysis showed that GhPRX genes expression were significantly different in microspore development between the sterility line-JinA and the maintainer line MB177. We confirmed the up-regulation of GhPRX107 and down-regulation of GhPRX128 in the sterile line compared to its maintainer line using qRT-PCR, suggesting their roles in pollen fertility. In addition, silencing GhPRX107 in cotton showed a significant decrease of the reactive oxygen species (ROS) levels of microsporocyte stage anthers compared to control. Overexpressing GhPRX107 in Arabidopsis significantly increased the ROS levels of anthers compared to wild type. In conclusion, we identified GhPRX107 as a determinant of ROS levels in anther. This work sets a foundation for PRX studies in pollen development.
bibliographic citation: Chen et al. (2022) Genome-wide identification and functional analysis of class III peroxidases in Gossypium hirsutum. PeerJ 10:e13635 https://doi.org/10.7717/peerj.13635
date submitted: 2021-12-30
date accepted: 2022-06-06
issued: 2022-07-01
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Chen
  given name: Yi
author list: Agent
  family name: Feng
  given name: Jiajia
author list: Agent
  family name: Qu
  given name: Yunfang
author list: Agent
  family name: Zhang
  given name: Jinlong
author list: Agent
  family name: Zhang
  given name: Li
author list: Agent
  family name: Liang
  given name: Dong
author list: Agent
  family name: Yang
  given name: Yujie
author list: Agent
  family name: Huang
  given name: Jinling
doi: 10.7717/peerj.13635
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-07-01
copyright: © 2022 Chen et al.
attribution name: Chen et al.

Recent advances in methods for in situ root phenotyping
type: item
type: AcademicArticle
description: Roots assist plants in absorbing water and nutrients from soil. Thus, they are vital to the survival of nearly all land plants, considering that plants cannot move to seek optimal environmental conditions. Crop species with optimal root system are essential for future food security and key to improving agricultural productivity and sustainability. Root systems can be improved and bred to acquire soil resources efficiently and effectively. This can also reduce adverse environmental impacts by decreasing the need for fertilization and fresh water. Therefore, there is a need to improve and breed crop cultivars with favorable root system. However, the lack of high-throughput root phenotyping tools for characterizing root traits in situ is a barrier to breeding for root system improvement. In recent years, many breakthroughs in the measurement and analysis of roots in a root system have been made. Here, we describe the major advances in root image acquisition and analysis technologies and summarize the advantages and disadvantages of each method. Furthermore, we look forward to the future development direction and trend of root phenotyping methods. This review aims to aid researchers in choosing a more appropriate method for improving the root system.
format: application/pdf
format: text/html
creator: Anchang Li
creator: Lingxiao Zhu
creator: Wenjun Xu
creator: Liantao Liu
creator: Guifa Teng
subject: Agricultural Science
subject: Plant Science
description: doi:10.7717/peerj.13638
publisher: PeerJ Inc.
rights: © 2022 Li et al.
abstract: Roots assist plants in absorbing water and nutrients from soil. Thus, they are vital to the survival of nearly all land plants, considering that plants cannot move to seek optimal environmental conditions. Crop species with optimal root system are essential for future food security and key to improving agricultural productivity and sustainability. Root systems can be improved and bred to acquire soil resources efficiently and effectively. This can also reduce adverse environmental impacts by decreasing the need for fertilization and fresh water. Therefore, there is a need to improve and breed crop cultivars with favorable root system. However, the lack of high-throughput root phenotyping tools for characterizing root traits in situ is a barrier to breeding for root system improvement. In recent years, many breakthroughs in the measurement and analysis of roots in a root system have been made. Here, we describe the major advances in root image acquisition and analysis technologies and summarize the advantages and disadvantages of each method. Furthermore, we look forward to the future development direction and trend of root phenotyping methods. This review aims to aid researchers in choosing a more appropriate method for improving the root system.
bibliographic citation: Li et al. (2022) Recent advances in methods for in situ root phenotyping. PeerJ 10:e13638 https://doi.org/10.7717/peerj.13638
date submitted: 2022-04-28
date accepted: 2022-06-06
issued: 2022-07-01
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Li
  given name: Anchang
author list: Agent
  family name: Zhu
  given name: Lingxiao
author list: Agent
  family name: Xu
  given name: Wenjun
author list: Agent
  family name: Liu
  given name: Liantao
author list: Agent
  family name: Teng
  given name: Guifa
doi: 10.7717/peerj.13638
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-07-01
copyright: © 2022 Li et al.
attribution name: Li et al.

Genetic diversity of enterotoxigenic Bacillus cereus strains in coriander in southwestern Mexico
type: item
type: AcademicArticle
description: Background Coriander, like other leafy green vegetables, is available all year round and is commonly consumed raw in Mexico as in other countries in the preparation of street or homemade food. Bacillus cereus (B. cereus) is a microorganism that can reach coriander because it is usually found in the soil and in some regions the vegetables are irrigated with polluted water. Therefore, the aim of this study was to determinate the presence of B. cereus in coriander used for human consumption in southwestern Mexico and determine the toxigenic profile, biofilm production, genes associated with the production of biofilms, sporulation rates, enzymatic profile, psychotropic properties, and genetic diversity of B. cereus. Methods Fresh coriander samples were collected from several vegetable retailers in different markets, microbiological analysis was performed. Molecular identification, genes related to the production of biofilm, and toxin gene profiling of B. cereus isolates were determined by PCR. The biofilm formation was measured by performing a crystal violet assay. The genetic diversity of B. cereus strains was determined by PCR of repetitive elements using oligonucleotide (GTG) 5. Results We found a frequency of B. cereus in vegetables was 20% (13/65). In this study, no strains with genes for the HBL toxin were found. In the case of genes related to biofilms, the frequency was low for sipW [5.8%, (1/17)] and tasA [11.7%, (2/17)]. B. cereus strains produce a low amount of biofilm with sporulation rates around 80%. As for genetic diversity, we observed that strains isolated from the same market, but different vegetable retailers are grouped into clusters. In the coriander marketed in southwestern Mexico, were found B. cereus strains with genes associated with the production of diarrheal toxins. Together, these results show actual information about the state of art of B. cereus strains circulating in the southwestern of Mexico.
format: application/pdf
format: text/html
creator: Daniel Alexander Castulo-Arcos
creator: Roberto Adame-Gómez
creator: Natividad Castro-Alarcón
creator: Aketzalli Galán-Luciano
creator: María Cristina Santiago Dionisio
creator: Marco A. Leyva-Vázquez
creator: Jose-Humberto Perez-Olais
creator: Jeiry Toribio-Jiménez
creator: Arturo Ramirez-Peralta
subject: Agricultural Science
subject: Microbiology
subject: Molecular Biology
subject: Plant Science
description: doi:10.7717/peerj.13667
publisher: PeerJ Inc.
rights: © 2022 Castulo-Arcos et al.
abstract: Background Coriander, like other leafy green vegetables, is available all year round and is commonly consumed raw in Mexico as in other countries in the preparation of street or homemade food. Bacillus cereus (B. cereus) is a microorganism that can reach coriander because it is usually found in the soil and in some regions the vegetables are irrigated with polluted water. Therefore, the aim of this study was to determinate the presence of B. cereus in coriander used for human consumption in southwestern Mexico and determine the toxigenic profile, biofilm production, genes associated with the production of biofilms, sporulation rates, enzymatic profile, psychotropic properties, and genetic diversity of B. cereus. Methods Fresh coriander samples were collected from several vegetable retailers in different markets, microbiological analysis was performed. Molecular identification, genes related to the production of biofilm, and toxin gene profiling of B. cereus isolates were determined by PCR. The biofilm formation was measured by performing a crystal violet assay. The genetic diversity of B. cereus strains was determined by PCR of repetitive elements using oligonucleotide (GTG) 5. Results We found a frequency of B. cereus in vegetables was 20% (13/65). In this study, no strains with genes for the HBL toxin were found. In the case of genes related to biofilms, the frequency was low for sipW [5.8%, (1/17)] and tasA [11.7%, (2/17)]. B. cereus strains produce a low amount of biofilm with sporulation rates around 80%. As for genetic diversity, we observed that strains isolated from the same market, but different vegetable retailers are grouped into clusters. In the coriander marketed in southwestern Mexico, were found B. cereus strains with genes associated with the production of diarrheal toxins. Together, these results show actual information about the state of art of B. cereus strains circulating in the southwestern of Mexico.
bibliographic citation: Castulo-Arcos et al. (2022) Genetic diversity of enterotoxigenic Bacillus cereus strains in coriander in southwestern Mexico. PeerJ 10:e13667 https://doi.org/10.7717/peerj.13667
date submitted: 2022-02-28
date accepted: 2022-06-10
issued: 2022-07-01
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Castulo-Arcos
  given name: Daniel Alexander
author list: Agent
  family name: Adame-Gómez
  given name: Roberto
author list: Agent
  family name: Castro-Alarcón
  given name: Natividad
author list: Agent
  family name: Galán-Luciano
  given name: Aketzalli
author list: Agent
  family name: Santiago Dionisio
  given name: María Cristina
author list: Agent
  family name: Leyva-Vázquez
  given name: Marco A.
author list: Agent
  family name: Perez-Olais
  given name: Jose-Humberto
author list: Agent
  family name: Toribio-Jiménez
  given name: Jeiry
author list: Agent
  family name: Ramirez-Peralta
  given name: Arturo
doi: 10.7717/peerj.13667
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-07-01
copyright: © 2022 Castulo-Arcos et al.
attribution name: Castulo-Arcos et al.

Manipulation of light quality is an effective tool to regulate photosynthetic capacity and fruit antioxidant properties of Solanum lycopersicum L. cv. ‘Microtom’ in a controlled environment
type: item
type: AcademicArticle
description: Light quality plays an essential role in setting plant structural and functional traits, including antioxidant compounds. This paper aimed to assess how manipulating the light spectrum during growth may regulate the photosynthetic activity and fruit bioactive compound synthesis in Solanum lycopersicum L. cv. ‘Microtom’ to improve plant physiological performance and fruit nutritional value. Plants were cultivated under three light quality regimes: red-green-blue LEDs (RGB), red-blue LEDs (RB) and white fluorescent lamps (FL), from sowing to fruit ripening. Leaf functional traits, photosynthetic efficiency, Rubisco and D1 protein expression, and antioxidant production in fruits were analyzed. Compared to FL, RGB and RB regimes reduced height and increased leaf number and specific leaf area, enhancing plant dwarf growth. The RGB regime improved photosynthesis and stomatal conductance despite lower biomass, favoring Rubisco synthesis and carboxylation rate than RB and FL regimes. The RB light produced plants with fewer flowers and fruits with a lower ascorbic acid amount but the highest polyphenol content, antioxidant capacity and SOD and CAT activities. Our data indicate that the high percentage of the green wavelength in the RGB regime promoted photosynthesis and reduced plant reproductive capacity compared to FL and RB. Conversely, the RB regime was the best in favoring the production of health-promoting compounds in tomato berries.
format: application/pdf
format: text/html
creator: Ermenegilda Vitale
creator: Violeta Velikova
creator: Tsonko Tsonev
creator: Giulia Costanzo
creator: Roberta Paradiso
creator: Carmen Arena
subject: Agricultural Science
subject: Plant Science
description: doi:10.7717/peerj.13677
publisher: PeerJ Inc.
rights: © 2022 Vitale et al.
abstract: Light quality plays an essential role in setting plant structural and functional traits, including antioxidant compounds. This paper aimed to assess how manipulating the light spectrum during growth may regulate the photosynthetic activity and fruit bioactive compound synthesis in Solanum lycopersicum L. cv. ‘Microtom’ to improve plant physiological performance and fruit nutritional value. Plants were cultivated under three light quality regimes: red-green-blue LEDs (RGB), red-blue LEDs (RB) and white fluorescent lamps (FL), from sowing to fruit ripening. Leaf functional traits, photosynthetic efficiency, Rubisco and D1 protein expression, and antioxidant production in fruits were analyzed. Compared to FL, RGB and RB regimes reduced height and increased leaf number and specific leaf area, enhancing plant dwarf growth. The RGB regime improved photosynthesis and stomatal conductance despite lower biomass, favoring Rubisco synthesis and carboxylation rate than RB and FL regimes. The RB light produced plants with fewer flowers and fruits with a lower ascorbic acid amount but the highest polyphenol content, antioxidant capacity and SOD and CAT activities. Our data indicate that the high percentage of the green wavelength in the RGB regime promoted photosynthesis and reduced plant reproductive capacity compared to FL and RB. Conversely, the RB regime was the best in favoring the production of health-promoting compounds in tomato berries.
bibliographic citation: Vitale et al. (2022) Manipulation of light quality is an effective tool to regulate photosynthetic capacity and fruit antioxidant properties of Solanum lycopersicum L. cv. ‘Microtom’ in a controlled environment. PeerJ 10:e13677 https://doi.org/10.7717/peerj.13677
date submitted: 2022-02-24
date accepted: 2022-06-13
issued: 2022-07-01
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Vitale
  given name: Ermenegilda
author list: Agent
  family name: Velikova
  given name: Violeta
author list: Agent
  family name: Tsonev
  given name: Tsonko
author list: Agent
  family name: Costanzo
  given name: Giulia
author list: Agent
  family name: Paradiso
  given name: Roberta
author list: Agent
  family name: Arena
  given name: Carmen
doi: 10.7717/peerj.13677
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-07-01
copyright: © 2022 Vitale et al.
attribution name: Vitale et al.

Spatial distribution of soil nutrients and evaluation of cultivated land in Xuwen county
type: item
type: AcademicArticle
description: It is of great significance to promote the quantitative research of soil science and the implementation of precision agriculture. On this basis, taking Xuwen County as the research object, this paper comprehensively analyzed the soil characteristics of cultivated land in Xuwen County and clarify the soil nutrient content and spatial distribution characteristics of cultivated land in Xuwen County, this paper comprehensively applied the methods of geostatistics, geographic information system (GIS) and fuzzy mathematics, and referred to the cultivated land quality grade standard (GB/T 33469-2016), to analyze the soil characteristics and evaluate the soil fertility of this region. The results show that the optimal interpolation model of soil pH and available phosphorus (AP) is a Gaussian model, and the optimal interpolation model of soil organic matter (SOM), available nitrogen (AN) and available potassium (AK) is a J-Bessel model. In addition, the spatial correlation of AK is weak, whereas pH, SOM, AN and AP show moderate spatial correlation. The proportion of excellent, good, average, medium and poor comprehensive fertility index are 26.00%, 32.67%, 19.33%, 19.00% and 3.00%, respectively. The overall level of soil fertility in Xuwen County is above the average, and the fertility quality presents an obvious trend of high in the South and low in the North. Areas that above average fertility are mainly distributed in Maichen Town, Qujie Town, Nanshan Town and Chengbei Town. The results can provide theoretical basis for improving the utilization rate of chemical fertilizer, fine management of cultivated land and ecological environment in this region, which can help in decision-making of precision fertilization.
format: application/pdf
format: text/html
creator: Chao Zheng
creator: Xiaofei Yang
creator: Zhiqiang Liu
creator: Kexing Liu
creator: Yongxiang Huang
subject: Soil Science
subject: Biogeochemistry
subject: Spatial and Geographic Information Science
description: doi:10.7717/peerj.13239
publisher: PeerJ Inc.
rights: © 2022 Zheng et al.
abstract: It is of great significance to promote the quantitative research of soil science and the implementation of precision agriculture. On this basis, taking Xuwen County as the research object, this paper comprehensively analyzed the soil characteristics of cultivated land in Xuwen County and clarify the soil nutrient content and spatial distribution characteristics of cultivated land in Xuwen County, this paper comprehensively applied the methods of geostatistics, geographic information system (GIS) and fuzzy mathematics, and referred to the cultivated land quality grade standard (GB/T 33469-2016), to analyze the soil characteristics and evaluate the soil fertility of this region. The results show that the optimal interpolation model of soil pH and available phosphorus (AP) is a Gaussian model, and the optimal interpolation model of soil organic matter (SOM), available nitrogen (AN) and available potassium (AK) is a J-Bessel model. In addition, the spatial correlation of AK is weak, whereas pH, SOM, AN and AP show moderate spatial correlation. The proportion of excellent, good, average, medium and poor comprehensive fertility index are 26.00%, 32.67%, 19.33%, 19.00% and 3.00%, respectively. The overall level of soil fertility in Xuwen County is above the average, and the fertility quality presents an obvious trend of high in the South and low in the North. Areas that above average fertility are mainly distributed in Maichen Town, Qujie Town, Nanshan Town and Chengbei Town. The results can provide theoretical basis for improving the utilization rate of chemical fertilizer, fine management of cultivated land and ecological environment in this region, which can help in decision-making of precision fertilization.
bibliographic citation: Zheng et al. (2022) Spatial distribution of soil nutrients and evaluation of cultivated land in Xuwen county. PeerJ 10:e13239 https://doi.org/10.7717/peerj.13239
date submitted: 2021-11-15
date accepted: 2022-03-18
issued: 2022-06-30
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Zheng
  given name: Chao
author list: Agent
  family name: Yang
  given name: Xiaofei
author list: Agent
  family name: Liu
  given name: Zhiqiang
author list: Agent
  family name: Liu
  given name: Kexing
author list: Agent
  family name: Huang
  given name: Yongxiang
doi: 10.7717/peerj.13239
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-06-30
copyright: ©2022 Zheng et al.
attribution name: Zheng et al.

Soil organic carbon and nitrogen storage under a wheat (Triticum aestivum L.)—maize (Zea mays L.) cropping system in northern China was modified by nitrogen application rates
type: item
type: AcademicArticle
description: Field cultivation practices have changing the carbon and nitrogen cycles in farmland ecosystem, soil organic carbon (SOC) and total nitrogen (TN) were the important parameters in maintaining soil quality and increasing agricultural productivity, however, N application’s effects on the SOC and TN storage capacity under intensive wheat-maize cropping system remain unclear. Therefore, we investigated the characteristics and relationships of SOC and TN for wheat-maize cropping system under nitrogen treatments. In doing so, continuous applications of four nitrogen application rates were examined: 0, 180, 240 and 300 kg ha−1 (N0, N180, N240 and N300, respectively). Wheat yields under N180 and N240 were significantly higher than that under N300, while the maize yields under N180, N240 and N300 were significantly higher than that under N0 by 79.79, 85.23 and 86.85%, respectively; the TN content and storage were significantly higher under N240 than that under other N levels in 40–60 cm soil layer after wheat growing season; the SOC content and storage under N180 and N240 were significant higher than that under N300 in 20–40 cm after maize growing season. The correlations between SOC and TN contents (or storage) were stronger after wheat planting than maize planting. These findings provide a basis for further studies on the effect of long-term N application on SOC and TN storage, crop quality and nitrogen use efficiency under wheat-maize cropping systems.
format: application/pdf
format: text/html
creator: Lifang Wang
creator: Shijie Liu
creator: Geng Ma
creator: Chenyang Wang
creator: Jutao Sun
subject: Agricultural Science
subject: Ecology
subject: Soil Science
description: doi:10.7717/peerj.13568
publisher: PeerJ Inc.
rights: © 2022 Wang et al.
abstract: Field cultivation practices have changing the carbon and nitrogen cycles in farmland ecosystem, soil organic carbon (SOC) and total nitrogen (TN) were the important parameters in maintaining soil quality and increasing agricultural productivity, however, N application’s effects on the SOC and TN storage capacity under intensive wheat-maize cropping system remain unclear. Therefore, we investigated the characteristics and relationships of SOC and TN for wheat-maize cropping system under nitrogen treatments. In doing so, continuous applications of four nitrogen application rates were examined: 0, 180, 240 and 300 kg ha−1 (N0, N180, N240 and N300, respectively). Wheat yields under N180 and N240 were significantly higher than that under N300, while the maize yields under N180, N240 and N300 were significantly higher than that under N0 by 79.79, 85.23 and 86.85%, respectively; the TN content and storage were significantly higher under N240 than that under other N levels in 40–60 cm soil layer after wheat growing season; the SOC content and storage under N180 and N240 were significant higher than that under N300 in 20–40 cm after maize growing season. The correlations between SOC and TN contents (or storage) were stronger after wheat planting than maize planting. These findings provide a basis for further studies on the effect of long-term N application on SOC and TN storage, crop quality and nitrogen use efficiency under wheat-maize cropping systems.
bibliographic citation: Wang et al. (2022) Soil organic carbon and nitrogen storage under a wheat (Triticum aestivum L.)—maize (Zea mays L.) cropping system in northern China was modified by nitrogen application rates. PeerJ 10:e13568 https://doi.org/10.7717/peerj.13568
date submitted: 2021-12-14
date accepted: 2022-05-20
issued: 2022-06-30
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Wang
  given name: Lifang
author list: Agent
  family name: Liu
  given name: Shijie
author list: Agent
  family name: Ma
  given name: Geng
author list: Agent
  family name: Wang
  given name: Chenyang
author list: Agent
  family name: Sun
  given name: Jutao
doi: 10.7717/peerj.13568
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-06-30
copyright: ©2022 Wang et al.
attribution name: Wang et al.

Electromyographic analysis of the serratus anterior and upper trapezius in closed kinetic chain exercises performed on different unstable support surfaces: a systematic review and meta-analysis
type: item
type: AcademicArticle
description: Background Multiple investigations have compared the electromyographic (EMG) activity of the scapular muscles between stable and unstable support surfaces during the execution of closed kinetic chain exercises. However, these comparative analyses have grouped different unstable surfaces (wobble board, BOSU, therapeutic ball, and suspension equipment) into a single data pool, without considering the possible differences in neuromuscular demand induced by each unstable support surface. This study aimed to analyze the individual effect of different unstable support surfaces compared to a stable support surface on scapular muscles EMG activity during the execution of closed kinetic chain exercises. Methodology A literature search was conducted of the Pubmed Central, ScienceDirect and SPORTDiscus databases. Studies which investigated scapular muscles EMG during push-ups and compared at least two support surfaces were included. The risk of bias of included articles was assessed using a standardized quality assessment form for descriptive, observational and EMG studies, and the certainty of the evidence was measured with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. A random-effects model was used to calculate effect sizes (ES, Hedge’s g). Results Thirty studies were selected in the systematic review. Of these, twenty-three low-to-high quality studies (498 participants) were included in the meta-analysis. The main analyzes revealed, in decreasing order, greater UT EMG activity during push-ups performed on suspension equipment (ES = 2.92; p = 0.004), therapeutic ball (ES = 1.03; p < 0.001) and wobble board (ES = 0.33; p = 0.003); without effect on the BOSU ball. In addition, no effect was observed for SA on any unstable device. The certainty of the evidence ranged from low to very low due to the inclusion of descriptive studies, as well as high imprecision, inconsistency, and risk of publication bias. Conclusion These findings could…
format: application/pdf
format: text/html
creator: Guillermo Mendez-Rebolledo
creator: Ignacio Orozco-Chavez
creator: Juan Morales-Verdugo
creator: Rodrigo Ramirez-Campillo
creator: Ann M.J. Cools
subject: Kinesiology
subject: Rehabilitation
subject: Sports Medicine
description: doi:10.7717/peerj.13589
publisher: PeerJ Inc.
rights: © 2022 Mendez-Rebolledo et al.
abstract: Background Multiple investigations have compared the electromyographic (EMG) activity of the scapular muscles between stable and unstable support surfaces during the execution of closed kinetic chain exercises. However, these comparative analyses have grouped different unstable surfaces (wobble board, BOSU, therapeutic ball, and suspension equipment) into a single data pool, without considering the possible differences in neuromuscular demand induced by each unstable support surface. This study aimed to analyze the individual effect of different unstable support surfaces compared to a stable support surface on scapular muscles EMG activity during the execution of closed kinetic chain exercises. Methodology A literature search was conducted of the Pubmed Central, ScienceDirect and SPORTDiscus databases. Studies which investigated scapular muscles EMG during push-ups and compared at least two support surfaces were included. The risk of bias of included articles was assessed using a standardized quality assessment form for descriptive, observational and EMG studies, and the certainty of the evidence was measured with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. A random-effects model was used to calculate effect sizes (ES, Hedge’s g). Results Thirty studies were selected in the systematic review. Of these, twenty-three low-to-high quality studies (498 participants) were included in the meta-analysis. The main analyzes revealed, in decreasing order, greater UT EMG activity during push-ups performed on suspension equipment (ES = 2.92; p = 0.004), therapeutic ball (ES = 1.03; p < 0.001) and wobble board (ES = 0.33; p = 0.003); without effect on the BOSU ball. In addition, no effect was observed for SA on any unstable device. The certainty of the evidence ranged from low to very low due to the inclusion of descriptive studies, as well as high imprecision, inconsistency, and risk of publication bias. Conclusion These findings could…
bibliographic citation: Mendez-Rebolledo et al. (2022) Electromyographic analysis of the serratus anterior and upper trapezius in closed kinetic chain exercises performed on different unstable support surfaces: a systematic review and meta-analysis. PeerJ 10:e13589 https://doi.org/10.7717/peerj.13589
date submitted: 2022-03-18
date accepted: 2022-05-24
issued: 2022-06-30
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Mendez-Rebolledo
  given name: Guillermo
author list: Agent
  family name: Orozco-Chavez
  given name: Ignacio
author list: Agent
  family name: Morales-Verdugo
  given name: Juan
author list: Agent
  family name: Ramirez-Campillo
  given name: Rodrigo
author list: Agent
  family name: Cools
  given name: Ann M.J.
doi: 10.7717/peerj.13589
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-06-30
copyright: ©2022 Mendez-Rebolledo et al.
attribution name: Mendez-Rebolledo et al.

Thrombocytopenia and increased risk of adverse outcome in COVID-19 patients
type: item
type: AcademicArticle
description: Background Thrombocytopenia was common in the coronavirus disease 2019 (COVID-19) patients during the infection, while the role of thrombocytopenia in COVID-19 pathogenesis and its relationship with systemic host response remained obscure. The study aimed to systematically evaluate the relationship between thrombocytopenia in COVID-19 patients and clinical, haematological and biochemical markers of the disease as well as adverse outcomes. Methods To assess the relationship between abnormal platelet levels and disease progression, a multi-center retrospective cohort study was conducted. COVID-19 patients with thrombocytopenia and a sub-cohort of matched patients without thrombocytopenia were compared for their clinical manifestations, haematological disorders, biochemical parameters, inflammatory markers and clinical outcome. Results Thrombocytopenia was present in 127 of 2,209 analyzed patients on admission. Compared with the control group, thrombocytopenia patients developed significantly higher frequency of respiratory failure (41.9% vs. 22.6%, P = 0.020), intensive care unit entrance (25.6% vs. 11.5%, P = 0.012), disseminated intravascular coagulation (45.2% vs. 10.6%, P < 0.001), more altered platelet morphology indexes and coagulation perturbation, higher levels of inflammatory markers. In addition, a significantly increased all-cause mortality (hazard ratio 3.08, 95% confidence interval 2.26–4.18, P < 0.001) was also observed in the patients with thrombocytopenia. Late development of thrombocytopenia beyond 14 days post-symptom was observed in 61 patients, from whom a comparable mortality rate yet longer duration to death was observed compared to those with early thrombocytopenia. Conclusions Our finding from this study adds to previous evidence that thrombocytopenia is associated with adverse outcome of the disease and recommend that platelet count and indices be included alongside other haematological, biochemical and inflammatory markers in COVID-19 patient…
format: application/pdf
format: text/html
creator: Yang Yuan
creator: Gang Wang
creator: Xi Chen
creator: Xiao-Lei Ye
creator: Xiao-Kun Li
creator: Rui Li
creator: Wan-Li Jiang
creator: Hao-Long Zeng
creator: Juan Du
creator: Xiao-Ai Zhang
creator: Hao Li
creator: Li-Qun Fang
creator: Qing-Bin Lu
creator: Wei Liu
subject: Epidemiology
subject: Gastroenterology and Hepatology
subject: Hematology
subject: Infectious Diseases
subject: COVID-19
description: doi:10.7717/peerj.13608
publisher: PeerJ Inc.
rights: © 2022 Yuan et al.
abstract: Background Thrombocytopenia was common in the coronavirus disease 2019 (COVID-19) patients during the infection, while the role of thrombocytopenia in COVID-19 pathogenesis and its relationship with systemic host response remained obscure. The study aimed to systematically evaluate the relationship between thrombocytopenia in COVID-19 patients and clinical, haematological and biochemical markers of the disease as well as adverse outcomes. Methods To assess the relationship between abnormal platelet levels and disease progression, a multi-center retrospective cohort study was conducted. COVID-19 patients with thrombocytopenia and a sub-cohort of matched patients without thrombocytopenia were compared for their clinical manifestations, haematological disorders, biochemical parameters, inflammatory markers and clinical outcome. Results Thrombocytopenia was present in 127 of 2,209 analyzed patients on admission. Compared with the control group, thrombocytopenia patients developed significantly higher frequency of respiratory failure (41.9% vs. 22.6%, P = 0.020), intensive care unit entrance (25.6% vs. 11.5%, P = 0.012), disseminated intravascular coagulation (45.2% vs. 10.6%, P < 0.001), more altered platelet morphology indexes and coagulation perturbation, higher levels of inflammatory markers. In addition, a significantly increased all-cause mortality (hazard ratio 3.08, 95% confidence interval 2.26–4.18, P < 0.001) was also observed in the patients with thrombocytopenia. Late development of thrombocytopenia beyond 14 days post-symptom was observed in 61 patients, from whom a comparable mortality rate yet longer duration to death was observed compared to those with early thrombocytopenia. Conclusions Our finding from this study adds to previous evidence that thrombocytopenia is associated with adverse outcome of the disease and recommend that platelet count and indices be included alongside other haematological, biochemical and inflammatory markers in COVID-19 patient…
bibliographic citation: Yuan et al. (2022) Thrombocytopenia and increased risk of adverse outcome in COVID-19 patients. PeerJ 10:e13608 https://doi.org/10.7717/peerj.13608
date submitted: 2021-08-24
date accepted: 2022-05-27
issued: 2022-06-30
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Yuan
  given name: Yang
author list: Agent
  family name: Wang
  given name: Gang
author list: Agent
  family name: Chen
  given name: Xi
author list: Agent
  family name: Ye
  given name: Xiao-Lei
author list: Agent
  family name: Li
  given name: Xiao-Kun
author list: Agent
  family name: Li
  given name: Rui
author list: Agent
  family name: Jiang
  given name: Wan-Li
author list: Agent
  family name: Zeng
  given name: Hao-Long
author list: Agent
  family name: Du
  given name: Juan
author list: Agent
  family name: Zhang
  given name: Xiao-Ai
author list: Agent
  family name: Li
  given name: Hao
author list: Agent
  family name: Fang
  given name: Li-Qun
author list: Agent
  family name: Lu
  given name: Qing-Bin
author list: Agent
  family name: Liu
  given name: Wei
doi: 10.7717/peerj.13608
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-06-30
copyright: ©2022 Yuan et al.
attribution name: Yuan et al.

Influence of Nordic walking with poles with an integrated resistance shock absorber on carbohydrate and lipid metabolic indices and white blood cell subpopulations in postmenopausal women
type: item
type: AcademicArticle
description: Background Regular and individualised physical activities have been shown to prevent adverse changes associated with the aging process. The main purpose of this study was to evaluate changes in carbohydrate and lipid metabolism and white blood cell (WBC) subpopulations in postmenopausal women participating in Nordic walking (NW) training and to compare the use of poles with an integrated resistance shock absorber (RSA) with the use of classic poles. Materials & Methods A total of 23 postmenopausal women participated in a 8-week programme of systematic physical activity between February and April. Before and after the training programme, somatic features and serum concentrations of 25-hydroxyvitamin D, glucose, and insulin, were assessed, as well as lipid profile and WBC count and its specific subpopulations. Results Analysis of differences in somatic features and biochemical indices before and after training in the group of women who used RSA poles showed significant decreases in fat mass content (p < 0.05), insulin (p < 0.05), homeostatic model assessment of insulin resistance (p < 0.05), triglycerides (p < 0.05), total cholesterol (p < 0.05) and monocytes (p ≤ 0.01). In the group of women who used classic poles (NW), there was a significant decrease in WBC (p ≤ 0.01), lymphocytes (p < 0.05), monocytes (p ≤ 0.01) and granulocytes (p < 0.05). Conclusion Increasing the training load through the use of RSA poles resulted in greater changes in carbohydrate and lipid metabolic indices compared to the use of classic NW poles. In turn, the more significant effect on WBC and its specific subpopulations count in the NW, compared to the RSA training programme, may indicate that specificity of training load is an important factor in modifying the immune system response.
format: application/pdf
format: text/html
creator: Anna Huta-Osiecka
creator: Krystian Wochna
creator: Rafał Stemplewski
creator: Katarzyna Marciniak
creator: Tomasz Podgórski
creator: Zbigniew Kasprzak
creator: Piotr Leszczyński
creator: Alicja Nowak
subject: Kinesiology
subject: Women’s Health
subject: Metabolic Sciences
subject: Sports Medicine
description: doi:10.7717/peerj.13643
publisher: PeerJ Inc.
rights: © 2022 Huta-Osiecka et al.
abstract: Background Regular and individualised physical activities have been shown to prevent adverse changes associated with the aging process. The main purpose of this study was to evaluate changes in carbohydrate and lipid metabolism and white blood cell (WBC) subpopulations in postmenopausal women participating in Nordic walking (NW) training and to compare the use of poles with an integrated resistance shock absorber (RSA) with the use of classic poles. Materials & Methods A total of 23 postmenopausal women participated in a 8-week programme of systematic physical activity between February and April. Before and after the training programme, somatic features and serum concentrations of 25-hydroxyvitamin D, glucose, and insulin, were assessed, as well as lipid profile and WBC count and its specific subpopulations. Results Analysis of differences in somatic features and biochemical indices before and after training in the group of women who used RSA poles showed significant decreases in fat mass content (p < 0.05), insulin (p < 0.05), homeostatic model assessment of insulin resistance (p < 0.05), triglycerides (p < 0.05), total cholesterol (p < 0.05) and monocytes (p ≤ 0.01). In the group of women who used classic poles (NW), there was a significant decrease in WBC (p ≤ 0.01), lymphocytes (p < 0.05), monocytes (p ≤ 0.01) and granulocytes (p < 0.05). Conclusion Increasing the training load through the use of RSA poles resulted in greater changes in carbohydrate and lipid metabolic indices compared to the use of classic NW poles. In turn, the more significant effect on WBC and its specific subpopulations count in the NW, compared to the RSA training programme, may indicate that specificity of training load is an important factor in modifying the immune system response.
bibliographic citation: Huta-Osiecka et al. (2022) Influence of Nordic walking with poles with an integrated resistance shock absorber on carbohydrate and lipid metabolic indices and white blood cell subpopulations in postmenopausal women. PeerJ 10:e13643 https://doi.org/10.7717/peerj.13643
date submitted: 2022-04-29
date accepted: 2022-06-07
issued: 2022-06-30
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Huta-Osiecka
  given name: Anna
author list: Agent
  family name: Wochna
  given name: Krystian
author list: Agent
  family name: Stemplewski
  given name: Rafał
author list: Agent
  family name: Marciniak
  given name: Katarzyna
author list: Agent
  family name: Podgórski
  given name: Tomasz
author list: Agent
  family name: Kasprzak
  given name: Zbigniew
author list: Agent
  family name: Leszczyński
  given name: Piotr
author list: Agent
  family name: Nowak
  given name: Alicja
doi: 10.7717/peerj.13643
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-06-30
copyright: ©2022 Huta-Osiecka et al.
attribution name: Huta-Osiecka et al.

Taxonomic and functional nematode diversity in Maldivian coral degradation zones: patterns across reef typologies and depths
type: item
type: AcademicArticle
description: The intensification of dredging and infilling activities in lagoons and on coral reefs are common practices in the Maldivian archipelago, and these activities alter the biodiversity of the bioconstructors and the functioning of the ecosystem. The alteration of environmental factors can also affect inconspicuous fauna, such as free-living nematodes. The implications of a reduction in biodiversity may transcend decreased taxonomic diversity, resulting in changes in functional diversity and redundancy; however, how the environmental conditions and human pressure affects the functionality of nematodes in Maldivian coral degradation zones (CDZs) remain poorly understood. In this paper, we examined changes in the taxonomic and functional diversity and the functional redundancy in nematode communities regarding the geographic location (atolls with various levels of human pressure), the exposure and topography of the reef (lagoon and ocean), the slope of the reef, and the depth. The functional diversity and redundancy were evaluated by considering two main biological traits of nematodes: i) the trophic strategy, and ii) the life strategy. The extremely high number of nematode genera observed in the Maldives is supported by the high complexity of the carbonate sediments. The reef exposure and depth were the most relevant environmental factors that influenced the taxonomic and functional diversity. The functional diversity, according to the trophic strategies, mirrored the taxonomic diversity because the adaptive plasticity of nematode buccal cavity structures is closely associated with the high biodiversity of the phylum. The high abundance of k-strategists in ocean reefs may indicate a higher ecological quality when compared to lagoon reefs; however, the absence of significant differences in life strategy functional diversity and functional redundancy indicates that a recovery process is underway. Analyses of nematode communities should be combined with standard investigati…
format: application/pdf
format: text/html
creator: Eleonora Grassi
creator: Monica Montefalcone
creator: Lucia Cesaroni
creator: Loretta Guidi
creator: Maria Balsamo
creator: Federica Semprucci
subject: Biodiversity
subject: Ecology
subject: Marine Biology
subject: Zoology
description: doi:10.7717/peerj.13644
publisher: PeerJ Inc.
rights: © 2022 Grassi et al.
abstract: The intensification of dredging and infilling activities in lagoons and on coral reefs are common practices in the Maldivian archipelago, and these activities alter the biodiversity of the bioconstructors and the functioning of the ecosystem. The alteration of environmental factors can also affect inconspicuous fauna, such as free-living nematodes. The implications of a reduction in biodiversity may transcend decreased taxonomic diversity, resulting in changes in functional diversity and redundancy; however, how the environmental conditions and human pressure affects the functionality of nematodes in Maldivian coral degradation zones (CDZs) remain poorly understood. In this paper, we examined changes in the taxonomic and functional diversity and the functional redundancy in nematode communities regarding the geographic location (atolls with various levels of human pressure), the exposure and topography of the reef (lagoon and ocean), the slope of the reef, and the depth. The functional diversity and redundancy were evaluated by considering two main biological traits of nematodes: i) the trophic strategy, and ii) the life strategy. The extremely high number of nematode genera observed in the Maldives is supported by the high complexity of the carbonate sediments. The reef exposure and depth were the most relevant environmental factors that influenced the taxonomic and functional diversity. The functional diversity, according to the trophic strategies, mirrored the taxonomic diversity because the adaptive plasticity of nematode buccal cavity structures is closely associated with the high biodiversity of the phylum. The high abundance of k-strategists in ocean reefs may indicate a higher ecological quality when compared to lagoon reefs; however, the absence of significant differences in life strategy functional diversity and functional redundancy indicates that a recovery process is underway. Analyses of nematode communities should be combined with standard investigati…
bibliographic citation: Grassi et al. (2022) Taxonomic and functional nematode diversity in Maldivian coral degradation zones: patterns across reef typologies and depths. PeerJ 10:e13644 https://doi.org/10.7717/peerj.13644
date submitted: 2022-04-13
date accepted: 2022-06-07
issued: 2022-06-30
is part of: PeerJ
license: https://creativecommons.org/licenses/by/4.0/
author list: Agent
  family name: Grassi
  given name: Eleonora
author list: Agent
  family name: Montefalcone
  given name: Monica
author list: Agent
  family name: Cesaroni
  given name: Lucia
author list: Agent
  family name: Guidi
  given name: Loretta
author list: Agent
  family name: Balsamo
  given name: Maria
author list: Agent
  family name: Semprucci
  given name: Federica
doi: 10.7717/peerj.13644
volume: 10
issn: 2167-8359
publication name: PeerJ
publication date: 2022-06-30
copyright: © 2022 Grassi et al.
attribution name: Grassi et al.

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