title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=646 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Avoidance of copper by fathead minnows (Pimephales promelas) requires an intact olfactory system link: https://peerj.com/articles/13988 last-modified: 2022-09-26 description: Fish can detect and respond to a wide variety of cations in their environment, including copper. Most often fish will avoid copper during behavioural trials; however, fish may also show no response or an attraction response, depending on the concentration(s) used. While it may seem intuitive that the response to copper requires olfaction, there is little direct evidence to support this, and what evidence there is remains incomplete. In order to test if olfaction is required for avoidance of copper by fathead minnows (Pimephales promelas) copper-induced movement was compared between fish with an intact olfactory system and fish with induced anosmia. Fish in a control group or a mock-anosmic group avoided copper (approximately 10 µg/L or 62.7 nM copper sulphate) while anosmic fish did not. The evidence demonstrates that an intact olfactory system is required for copper sensing in fish. creator: Rubab Fatima creator: Robert Briggs creator: William A. Dew uri: https://doi.org/10.7717/peerj.13988 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Fatima et al. title: What’s the effectiveness of stocking actions in small creeks? The role of water discharge behind hatchery trout downstream movement link: https://peerj.com/articles/14069 last-modified: 2022-09-26 description: Fish stocking to enhance freshwater fisheries or to improve the conservation status of endangered fish species is a common practice in many countries. Little is known, however, of the effectiveness of these practices in spite of the high efforts and investments required. The movement of subadult/adult hatchery-released brown trout Salmo trutta L. was studied by passive telemetry in a small tributary of Lake Lugano (i.e., Laveggio Creek, Canton Ticino, Switzerland). Hatchery fish, together with some resident wild individuals sampled during electrofishing surveys, were tagged with Passive Integrated Transponders (PIT) tags. Hatchery fish were released upstream and downstream a submersible monitoring antenna, which was anchored to the streambed in a pass-over orientation. The number of hatchery fish detected daily by the antenna (divided between fish released upstream and downstream the antenna) was analyzed in relation to the daily water discharge, to search for similar patterns in their fluctuation over time. Only the movement of fish released upstream the antenna displayed a significant relationship with water discharge, with the highest number of fish detected during periods of high-water flow, occurring after heavy rains. High-water discharge events had a significant role in hatchery trout downstream movement in our study site, likely acting as a driver for the downstream migration to Lake Lugano. Such events contributed to the poor effectiveness of stocking actions in this small tributary, providing further evidence against stocking strategies based on subadult/adult fish. creator: Stefano Brignone creator: Vanessa De Santis creator: Tiziano Putelli creator: Christophe Molina creator: Armando Piccinini creator: Richard A. Carmichael creator: Pietro Volta uri: https://doi.org/10.7717/peerj.14069 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Brignone et al. title: Improved response inhibition induced by attentional capture is associated with physical activity link: https://peerj.com/articles/14083 last-modified: 2022-09-26 description: The ability to stop a response promptly when a stop signal is presented is named response inhibition. It is generally accepted that the process of response inhibition requires a subject to pay attention to the stop instruction and then cancel the action. A wealth of converging evidence suggests that physical activity (PA) can promote response inhibition, but the potential contributions of attentional capture to the relationship between PA and response inhibition are currently unknown. In this study, the standard stop-signal task (SST) and two novel versions of the SST were used to solve this gap. A total of 58 college students were divided into a higher PA group and a lower PA group, respectively. In Experiment 1, the classical SST determined that the participants in the higher PA group displayed a significantly faster stop-signal reaction time (SSRT) than those in the lower PA group. Experiment 2 separated the attentional capture in the SST and revealed that the participants in the higher PA group could detect the signal faster than those in the lower PA group. Experiment 3 further added a stop signal to Experiment 2 and demonstrated that the participants in the higher PA group could more effectively deploy attentional resources to complete the task. Overall, these findings indicate that PA is positively associated with response inhibition and that the positive relationship is associated with effective allocation of attentional resources for faster attentional capture. creator: Hao Zhu creator: Jiuyang Xu creator: Yue Zheng creator: Guiping Jiang creator: Xinyi Huang creator: Xiaohuan Tan creator: Xueping Wu uri: https://doi.org/10.7717/peerj.14083 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Zhu et al. title: Does quality of novice hand-tied square knots improve with repetition during a single training session? link: https://peerj.com/articles/14106 last-modified: 2022-09-26 description: BackgroundKnot tying is a key surgical skill for novices, and repetition over several training sessions improves knot tying. This study examined the effects of repetition within a single training session on quality of knotted loops and compared results of novice trainees and experienced surgeons.MethodsUsing 0.55 mm nylon monofilament fishing line, novices and surgeons each hand-tied 20 knotted loops, using a 2=1=1=1 configuration (surgeon’s throw and three square throws). Loops were mechanically tested with a single load to failure.ResultsAll loops tolerated five newtons (N) preload. More than 70% of novice and surgeon knots failed by slipping or untying, and 8.8% of novice knots and 2.5% of surgeon’s knots were considered dangerous. Surgeons’ loops had less extension at preload, indicating better loop security. However, during single test to failure, there was no difference in mean extension or maximum load between surgeons and novices. There was no significant difference in results of mechanical testing or modes of failure for the first and last ten knotted loops, or the first, second, third, and fourth sets of knotted loops.DiscussionWith appropriate training, novices can construct knots as strong and secure as experienced surgeons. A large percentage of knotted loops are insecure under testing conditions; extra throws may be required when using large diameter monofilament nylon. Novices may require extra training in maintenance of loop security when constructing square knots. Tying more than five or 10 knotted loops within a single training session does not provide added benefits for novices. creator: Karen Tobias creator: Pierre-Yves Mulon creator: Alec Daniels creator: Xiaocun Sun uri: https://doi.org/10.7717/peerj.14106 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Tobias et al. title: Hidden interactions in the intertidal rocky shore: variation in pedal mucus microbiota among marine grazers that feed on epilithic biofilm communities link: https://peerj.com/articles/13642 last-modified: 2022-09-23 description: In marine ecosystems, most invertebrates possess diverse microbiomes on their external surfaces, such as those found in the pedal mucus of grazing gastropods and chitons that aids displacement on different surfaces. The microbes are then transported around and placed in contact with free-living microbial communities of micro and other macro-organisms, potentially exchanging species and homogenizing microbial composition and structure among grazer hosts. Here, we characterize the microbiota of the pedal mucus of five distantly related mollusk grazers, quantify differences in microbial community structure, mucus protein and carbohydrate content, and, through a simple laboratory experiment, assess their effects on integrated measures of biofilm abundance. Over 665 Amplicon Sequence Variants (ASVs) were found across grazers, with significant differences in abundance and composition among grazer species and epilithic biofilms. The pulmonate limpet Siphonaria lessonii and the periwinkle Echinolittorina peruviana shared similar microbiota. The microbiota of the chiton Chiton granosus, keyhole limpet Fissurella crassa, and scurrinid limpet Scurria araucana differed markedly from one another, and form those of the pulmonate limpet and periwinkle. Flavobacteriaceae (Bacteroidia) and Colwelliaceae (Gammaproteobacteria) were the most common among microbial taxa. Microbial strict specialists were found in only one grazer species. The pedal mucus pH was similar among grazers, but carbohydrate and protein concentrations differed significantly. Yet, differences in mucus composition were not reflected in microbial community structure. Only the pedal mucus of F. crassa and S. lessonii negatively affected the abundance of photosynthetic microorganisms in the biofilm, demonstrating the specificity of the pedal mucus effects on biofilm communities. Thus, the pedal mucus microbiota are distinct among grazer hosts and can affect and interact non-trophically with the epilithic biofilms on which grazers feed, potentially leading to microbial community coalescence mediated by grazer movement. Further studies are needed to unravel the myriad of non-trophic interactions and their reciprocal impacts between macro- and microbial communities. creator: Clara Arboleda-Baena creator: Claudia Belén Pareja creator: Isadora Pla creator: Ramiro Logares creator: Rodrigo De la Iglesia creator: Sergio Andrés Navarrete uri: https://doi.org/10.7717/peerj.13642 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Arboleda-Baena et al. title: Utilizing network pharmacology and experimental validation to investigate the underlying mechanism of phellodendrine on inflammation link: https://peerj.com/articles/13852 last-modified: 2022-09-23 description: BackgroundPhellodendrine, one of the characteristic and important active components of Cortex phellodendri, has been proven to show anti-inflammatory effects. However, the underlying mechanism of phellodendrine on inflammation remains largely unclear.Aim of the studyIn this study, network pharmacology and experimental validation were used to explore the underlying mechanism of phellodendrine on inflammation.Materials and MethodsPubChem and SwissADME database were used to evaluate the drug-likeness and other characteristics of phellodendrine. The targets of phellodendrine for the treatment of inflammation were analyzed with multiple databases. Other extensive analyses including protein–protein interaction, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes pathway enrichment were accomplished with the STRING database, Cytoscape software, and DAVID database. Moreover, the effect of phellodendrine on anti-inflammation was proven in RAW264.7.ResultsThe network pharmacology results indicated that phellodendrine had drug potential. Phellodendrine acted directly on 12 targets, including PTGS1, PTGS2, HTR1A, and PIK3CA, and then regulated cAMP, estrogen, TNF, serotonergic synapse, and other signaling pathways to exert anti-inflammatory effects. The experimental results showed that phellodendrine reduced the levels of IL-6 compared with the LPS group in 24 h and changed the mRNA expression of PTGS1, PTGS2, HSP90ab1, AKT1, HTR1A, PI3CA, and F10.ConclusionOur research preliminarily uncovered the therapeutic mechanisms of phellodendrine on inflammation with multiple targets and pathways. Phellodendrine may be a potential treatment for inflammation-related diseases related to the cAMP and TNF signaling pathways. creator: Lili Hu creator: Jue Wang creator: Na Wu creator: Xiaoge Zhao creator: Donghui Cai uri: https://doi.org/10.7717/peerj.13852 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Hu et al. title: A questionnaire development to assess the social representation of nurses in the Basque Country: a psychometric assessment link: https://peerj.com/articles/13903 last-modified: 2022-09-23 description: BackgroundOnly a few Spanish studies have explored how nurses are seen by society and no validated tools exist for this purpose in the scientific literature.ObjectivesThe aim was create and evaluate the psychometric characteristics of a questionnaire that explored the social representation of nursing in social and health care.MethodsQualitative and quantitative methods were used to develop the questionnaire and the first version was created based on existing studies. A three-round Delphi technique was used that involved nurses, doctors, journalists and a politician. The pilot questionnaire was then tested and retested with 23 journalism students, with an interval of 10–14 days between the two phases. After further modifications, the questionnaire was sent to all the third and fourth year journalism students at the University of the Basque Country. Principal component factor analysis was used to identify the key components for the questionnaire.ResultsA total of 141 third and fourth year journalism students took part in the study. The internal consistency of the 43-item perception section of the questionnaire had a Cronbach’s alpha value of 0.90. The 42.7% agreed or strongly agreed that nursing was an eminently scientific profession and 26.3% agreed or strongly agreed with the statement that nurses were presented in the media as health educators and disseminators. Just under a fifth (19.9%) agreed with the statement that society was aware of the competencies that nurses required.ConclusionsThe questionnaire provided the first validated tool that allowed researchers to assess how nursing, and all of its areas of professional development, were perceived by society. This could enable studies to assess the evolution of the profession over time and between different socio-cultural contexts. creator: Verónica Tíscar-González creator: Leire Iturregui-Mardaras creator: Eztizen Miranda-Bernabé creator: Cristina Bermúdez-Ampudia creator: Maria Ángeles Cidoncha-Moreno creator: Sendoa Ballesteros-Peña uri: https://doi.org/10.7717/peerj.13903 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Tíscar-González et al. title: Interelemental osteohistological variation in Massospondylus carinatus and its implications for locomotion link: https://peerj.com/articles/13918 last-modified: 2022-09-23 description: Massospondylus carinatus Owen, 1854 is an iconic basal sauropodomorph dinosaur from the Early Jurassic of southern Africa. Over 200 specimens have been referred to this taxon, spanning the entire ontogenetic series from embryo to adult. Consequently, it provides an ideal sample for investigating dinosaur developmental biology, including growth patterns and growth rates, through osteohistological analysis. Massospondylus carinatus was the first early-branching sauropodomorph dinosaur for which a femoral growth series was sampled. Since then, growth series of other non-avian dinosaur taxa have shown that growth plasticity, interelemental variation, and ontogenetic locomotory shifts can complicate our understanding of growth curves and patterns. To investigate these questions further, it is necessary to sample multiple skeletal elements from multiple individuals across a large range of sizes, something that is often hindered by the incompleteness of the fossil record. Here, we conducted a broad, multielement osteohistological study of long bones (excluding metapodials) from 27 specimens of Massospondylus carinatus that span its ontogenetic series. Our study reveals substantial variations in growth history. A cyclical woven-parallel complex is the predominant bone tissue pattern during early and mid-ontogeny, which transitions to slower forming parallel-fibred bone during very late ontogeny. The bone tissue is interrupted by irregularly spaced cyclical growth marks (CGMs) including lines of arrested growth indicating temporary cessations in growth. These CGMs show that the previously recorded femoral growth plasticity is also visible in other long bones, with a poor correlation between body size (measured by midshaft circumference) and CGM numbers. Furthermore, we found that the growth trajectory for an individual can vary depending on which limb element is studied. This makes the establishment of an accurate growth curve and determination of the onset of reproductive maturity difficult for this taxon. Finally, we found no evidence of differential growth rates in forelimb vs hindlimb samples from the same individual, providing further evidence falsifying hypothesised ontogenetic postural shifts in Massospondylus carinatus. creator: Kimberley EJ Chapelle creator: Paul M. Barrett creator: Jonah N. Choiniere creator: Jennifer Botha uri: https://doi.org/10.7717/peerj.13918 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Chapelle et al. title: Antimicrobial and cytotoxic effects of marine sponge extracts Agelas clathrodes, Desmapsamma anchorata and Verongula rigida from a Caribbean Island link: https://peerj.com/articles/13955 last-modified: 2022-09-23 description: Although marine sponges are known for their antimicrobial, antifungal and cytotoxic activity, very few studies have been carried out on endemic species of Martinique. Martinique is part of the Agoa Sanctuary, a marine protected area that includes the exclusive economic zones (EEZ) of the French Caribbean islands, making it an abundant source of marine species. To highlight the potential of this area for the discovery of marine biomolecules with antipathogenic and antitumor activities, we tested the aqueous and ethanolic extracts of sponge species Agelas clathrodes, Desmapsamma anchorata and Verongula rigida. Five bacterial strains: Bacillus cereus (CIP 78.3), Escherichia coli (CIP 54.127), Pseudomonas aeruginosa (CIP A22), Staphylococcus aureus (CIP 67.8) and Staphylococcus saprophyticus (CIP 76125) were evaluated, as well as four tumor cell lines: breast cancer (MDA-MB231), glioblastoma (RES259) and leukemia (MOLM14 and HL-60). Antimicrobial activity was evaluated using the disc diffusion technique by determining the minimum inhibitory and minimum bactericidal concentrations. Tumor cytotoxic activity was determined in vitro by defining the minimum concentration of extracts that would inhibit cell growth. Ethanolic extracts of Agelas clathrodes were bactericidal for Staphylococcus aureus and Staphylococcus saprophyticus strains, as well as strongly cytotoxic (IC50 < 20 µg/mL) on all cancer cell lines. Verongula rigida also showed strong cytotoxic activity on cell lines but no antimicrobial activity. These results are innovative for this species on these bacterial lines, highlighting the potential of sponge extracts from this area as bioactive compounds sources. creator: Julie Piron creator: Stephane Betzi creator: Jessica Pastour creator: Audrey Restouin creator: Rémy Castellano creator: Yves Collette creator: Niklas Tysklind creator: Juliette Smith-Ravin creator: Fabienne Priam uri: https://doi.org/10.7717/peerj.13955 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Piron et al. title: Influence of planting yellowhorn (Xanthoceras sorbifolium Bunge) on the bacterial and fungal diversity of fly ash link: https://peerj.com/articles/14015 last-modified: 2022-09-23 description: Phytoremediation is a low-cost solution to fly ash pollution and the rhizosphere interactions between plant roots and the fly ash microbiome were important for the phytoremediation. To analyze the dynamic changes of the rhizosphere microbiome during yellowhorn cultivation in fly ash, the bacterial 16S rRNA gene V3–V4 region and the fungal ITS region of the rhizosphere microbiome were sequenced using Illumina MiSeq technology. The changes in fly ash physicochemical properties and the heavy metal content of different yellowhorn tissues were also analyzed. The results showed that both the bacterial and fungal communities were noticeably different after yellowhorn cultivation compared with the control sample. Proteobacteria and Acidobacteria levels increased (p < 0.05) and Firmicutes and Actinobacteria decreased (p < 0.05) in the bacterial community after yellowhorn cultivation. In the fungal community, Ascomycota and Mortierellomycota decreased (p < 0.05), while Chytridiomycota increased (p < 0.05). The levels of four heavy metals (Cr, Cd, Hg, Pb and As) decreased in the fly ash after yellowhorn cultivation. These metals were absorbed by the yellowhorn plants and accumulated in the fibrous root, taproot, stem and leaf tissues of these plants. Accordingly, the abundance of bacteria that could solubilize heavy metals increased (p < 0.05). In summary, the cultivation of yellowhorn affected the composition of the rhizosphere microbial communities in fly ash, which is of great significance for the biological remediation of fly ash. creator: Zehui Liu creator: Jianguo Zhao creator: Jinxian Huo creator: Hongfang Ma creator: Zhiwen Chen uri: https://doi.org/10.7717/peerj.14015 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Liu et al.