Ectomycorrhizal fungal communities associated with Larix gemelinii Rupr. in the Great Khingan Mountains, China
Larix gemelinii is an important tree species in the Great Khingan Mountains in Northeast China with a high economic and ecological value for its role in carbon sequestration and as a source of lumber and nuts. However, the ectomycorrhizal (EM) fungal diversity and community composition of this tree remain largely undefined. We examined EM fungal communities associated with L. gemelinii from three sites in the Great Khingan Mountains using Illumina Miseq to sequence the rDNA ITS2 region and evaluated the impact of spatial, soil, and climatic variables on the EM fungal community. A total of 122 EM fungal operational taxonomic units (OTUs) were identified from 21 pooled-root samples, and the dominant EM fungal lineages were /tricholoma, /tomentella-thelephora, /suillus-rhizopogon, and /piloderma. A high proportion of unique EM fungal OTUs were present; some abundant OTUs largely restricted to specific sites. EM fungal richness and community assembly were significantly correlated with spatial distance and climatic and soil variables, with mean annual temperature being the most important predictor for fungal richness and geographic distance as the largest determinant for community turnover. Our findings indicate that L. gemelinii has a rich and distinctive EM fungal community contributing to our understanding of the montane EM fungal community structure from the perspective of a single host plant that has not been previously reported.
Wang et al. (2021) Ectomycorrhizal fungal communities associated with Larix gemelinii Rupr. in the Great Khingan Mountains, China. PeerJ 9:e11230 https://doi.org/10.7717/peerj.11230
Diversity patterns and drivers of soil microbial communities in urban and suburban park soils of Shanghai, China
Background The rapid expansion of urbanization leads to significant losses of soil ecological functions. Microbes directly participate in key soil processes and play crucial roles in maintaining soil functions. However, we still have a limited understanding of underlying mechanisms shaping microbial communities and the interactions among microbial taxa in park soils. Methods In this study, the community variations of bacteria and fungi in urban and suburban park soils were investigated in Shanghai, China. Real-time PCR and high-throughput Illumina sequencing were used to examine the microbial abundance and community composition, respectively. Results The results showed that soil molecular biomass and fungal abundance in urban park soils were significantly higher than those in suburban park soils, while no significant difference was observed in the bacterial abundance between urban and suburban park soils. The alpha diversity of soil microbes in urban and suburban park soils was similar to each other, except for Chao1 index of fungal communities. The results of similarity analysis (ANOSIM) revealed remarkable differences in the composition of bacterial and fungal communities between urban and suburban park soils. Specifically, park soils in urban areas were enriched with the phyla Methylomirabilota and Verrucomicrobiota, while the relative abundance of Gemmatimonadota was higher in suburban park soils. Moreover, the fungal class Eurotiomycetes was also enriched in urban park soils. Compared with suburban park soils, nodes and average paths of the bacterial and fungal networks were higher in urban park soils, but the number of module hubs and connectors of the bacterial networks and negative interactions among bacterial taxa were lower. Compared with suburban park soils, Acidobacteriota bacterium and Mortierellomycota fungus played more important roles in the ecological networks of urban park soils. Soil available zinc (Zn), available nitrogen (N), pH, and total potassium (K) significantly affected fungal community composition in park soils in Shanghai. Soil available Zn was also the most important factor affecting the bacterial community composition in this study. Conclusion There were significant differences in the soil molecular biomass, fungal abundance, and the community composition and co-occurrence relations of both soil bacterial and fungal communities between urban and suburban park soils. Soil available Zn played an important part in shaping the structures of both the bacterial and fungal communities in park soils in Shanghai.
Zhang et al. (2021) Diversity patterns and drivers of soil microbial communities in urban and suburban park soils of Shanghai, China. PeerJ 9:e11231 https://doi.org/10.7717/peerj.11231
Melatonin ameliorates myocardial injury by reducing apoptosis and autophagy of cardiomyocytes in a rat cardiopulmonary bypass model
Background Myocardial injury is a frequent complication after cardiac surgery with cardiopulmonary bypass (CPB). This study aimed to test the hypothesis that melatonin could attenuate myocardial injury in a rat CPB model. Methods Eighteen male Sprague-Dawley rats were randomly divided into three groups, n = 6 for each group: the sham operation (SO) group, CPB group and melatonin group. Rats in the SO group underwent cannulation without CPB, rats in CPB group intraperitoneal injected an equal volume of vehicle daily for 7 days before being subjected to CPB and rats in melatonin group intraperitoneal injected 20 mg/kg of melatonin solution daily for 7 days before being subjected to CPB. After 120 min for CPB, the expression levels of plasma interleukin (IL) -6, IL-1β, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), creatine kinase (CK) -MB and cardiac troponin T (cTnT) were measured. Reactive oxygen species (ROS) were detected by dihydroethidium (DHE). Apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining. Mitochondrial damage and autophagosomes were detected by electron microscopy. Apoptosis inducing factor (AIF) was detected by immunofluorescence. The expression of B cell lymphoma/leukemia2 associated X (Bax), B cell lymphoma/leukemia 2 (Bcl-2), cytochrome C (Cyto-C), cleaved caspase-9, AKT, p-AKT, signal transducer and activator of transcription 3 (STAT3), p-STAT3, LC3, P62, mechanistic target of rapamycin kinase (mTOR), p-mTOR and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were determined using western blotting. Results Melatonin significantly decreased the levels of IL-1β, IL-6, MDA, CK-MB and cTnT and increased the levels of SOD and GSH-Px, all of which were altered by CPB. Melatonin reduced cardiomyocyte superoxide production, the apoptosis index and autophagy in cardiomyocytes induced by CPB. The AKT, STAT3 and mTOR signaling pathways were activated by melatonin during CPB. Conclusion Melatonin may serve as a cardioprotective factor in CPB by inhibiting oxidative damage, apoptosis and autophagy. The AKT, STAT3 and mTOR signaling pathways were involved in this process.
Huang et al. (2021) Melatonin ameliorates myocardial injury by reducing apoptosis and autophagy of cardiomyocytes in a rat cardiopulmonary bypass model. PeerJ 9:e11264 https://doi.org/10.7717/peerj.11264
Explorations of avoidance and approach coping and perceived stress with a computer-based avatar task: detrimental effects of resignation and withdrawal
Background Individuals differ in how they react to stress or trauma through different coping styles in which they may deal directly with a stressor by adopting approach coping styles or disengage with a stressor by utilizing avoidant coping styles. Avoidant coping styles have been linked to adverse outcomes including psychological distress, anxiety disorders, and post-traumatic stress disorder (PTSD). Recently, avoidance coping styles as measured by a subset of items on the Brief COPE were found to have a weak positive relationship with performance on a computer-based avatar task which is related to avoidant personality temperaments. This avatar task was developed as an alternative for paper and pencil self-report inventories for measuring avoidant tendencies based on possible response biases of avoidant individuals. In the current study, avoidance and approach coping styles as measured by the Brief Approach/Avoidance Coping Questionnaire (BACQ) were compared to avoidant coping as measured by the Brief COPE and performance on the avatar task. In addition to approach and avoidance coping, the BACQ also measures active avoidance coping (i.e., diversion) and passive avoidance coping (i.e., resignation and withdrawal). The relationships between approach and avoidance coping and performance on the avatar task were also analyzed with the outcome of perceived stress as measured by the Perceived Stress Scale (PSS). Methods One hundred undergraduates voluntarily completed the BACQ, the Brief COPE, and the PSS. Participants also completed a computer-based task in which they guided an avatar through a series of social situations where they indicated how they would interact with or avoid interacting with strangers. Results Approach coping had a weak negative relationship to avoidance coping as measured by the BACQ and the Brief COPE. Performance on the avatar task had a moderate positive relationship with avoidance coping (diversion as well as resignation and withdrawal) as measured by the BACQ and a moderate negative relationship with approach coping as measured by the BACQ. A model including only approach, diversion, and resignation and withdrawal coping best predicted performance on the avatar task in a linear regression model. While resignation and withdrawal coping and diversion coping had moderate positive relationships to avatar task scores, only resignation and withdrawal had a strong positive relationship to perceived stress. A model than included only resignation and withdrawal coping best predicted perceived stress in a linear regression model. Overall, passive avoidant coping styles (i.e., resignation and withdrawal), but not active avoidant coping style (i.e., diversion), were related to perceived stress. These results support the continued study of multiple aspects of avoidant coping styles as well as the avatar task to increase our understanding of the maladaptive effects of excessive avoidance in the face of stress.
Allen (2021) Explorations of avoidance and approach coping and perceived stress with a computer-based avatar task: detrimental effects of resignation and withdrawal. PeerJ 9:e11265 https://doi.org/10.7717/peerj.11265
Conjuring up creativity: the effect of performing magic tricks on divergent thinking
Research suggests that learning to perform magic tricks can promote both physical and psychological wellbeing. The current study extended this work by examining the impact of learning magic tricks on divergent thinking. A group of 10- to 11-year-old children completed Guilford’s Alternate Uses Test both before and after participating in either a magic-based, or art-based, activity. As predicted, compared to the art-based activity, the magic-based activity resulted in a significantly greater increase in both AUT Fluency and AUT Originality scores. Rosenberg’s Self-Esteem Scale and Dweck’s Implicit Theories of Intelligence Scale for Children was also completed after each activity, and participants’ self-esteem scores were higher after the art-based activity than the magic-based activity. In an exploratory aspect of the study, the AUT was re-administered to both groups three weeks later, and yielded no significant differences. The practical and theoretical implications of these findings are discussed, along with recommendations for future research.
Wiseman et al. (2021) Conjuring up creativity: the effect of performing magic tricks on divergent thinking. PeerJ 9:e11289 https://doi.org/10.7717/peerj.11289
Morphological grounds for the obligate aerial respiration of an aquatic snail: functional and evolutionary perspectives
The freshwater caenogastropod family Ampullariidae is emerging as a model for a variety of studies, among them, the evolution of terrestriality. A common character of the family is that all its members bear a lung while retaining the ancestral gill. This ensures that many ampullariids are able to inhabit poorly oxygenated waters, to bury in the mud during estivation, and to temporarily leave the water, in some species for oviposition. To these characters Pomacea canaliculata (Caenogastropoda, Ampullariidae) adds that is an obligate air-breather. In a recent paper, we showed the gill epithelium of P. canaliculata has a set of characteristics that suggest its role for oxygen uptake may be less significant than its role in ionic/osmotic regulation and immunity. We complement here our morphological investigation on the respiratory organs of P. canaliculata by studying the lung of this species at the anatomical (3D reconstructions of the blood system and nerve supply), histological and ultrastructural levels. The circulation of the gill and the lung are interconnected so that the effluence of blood from the gill goes to the lung where it completes oxygenation. Besides that, we found the lung cavity is lined by a pavement epithelium that encloses an anastomosing network of small blood spaces resting over a fibromuscular layer, which altogether form the respiratory lamina. The pavement cells form a blood-gas barrier that is 80–150 nm thick and thus fulfils the requirements for an efficient gas exchanger. Tufts of ciliary cells, together with some microvillar and secretory cells, are interspersed in the respiratory lamina. Rhogocytes, which have been proposed to partake in metal depuration and in the synthesis of hemocyanin in other gastropods, were found below the respiratory lamina, in close association with the storage cell tissue. In light of these findings, we discuss the functional role of the lung in P. canaliculata and compare it with that of other gastropods. Finally, we point to some similarities in the pattern of the evolution of air dependence in this family.
Rodriguez et al. (2021) Morphological grounds for the obligate aerial respiration of an aquatic snail: functional and evolutionary perspectives. PeerJ 9:e10763 https://doi.org/10.7717/peerj.10763
Unraveling the genetic diversity and structure of Quercus liaotungensis population through analysis of microsatellite markers
Background Quercus liaotungensis Koidz. is an ecologically and economically important tree species widely distributed in Northern China. However, the effective assessment, utilization, and protection of Q. liaotungensis resources remain unexplored. Methods In total, 120 samples obtained from 12 Q. liaotungensis populations of Northern China were investigated for genetic diversity and structure using 19 simple sequence repeat (SSR) primer pairs. Results The total number of alleles detected was 293, the average number of effective allele (Ne) was 6.084, the genetic differentiation coefficient (Fst) was 0.033, and the mean observed heterozygosity (Ho) and expected heterozygosity (He) were 0.690 and 0.801, respectively. Moreover, analysis of molecular variance (AMOVA) showed a 5.5% genetic variation among 12 Q. liaotungensis populations, indicating that a high level of genetic diversity and a low degree of genetic differentiation among Q. liaotungensis populations. STRUCTURE and cluster analysis divided the 12 Q. liaotungensis populations into the following three subpopulations: Bashang Plateau subpopulation (SH), Liaodong Peninsula subpopulation (NC), and Loess Plateau subpopulation (other 10 populations). The cluster analysis based on 19 climatic factors was consistent with the genetic structure. A positive correlation was found between genetic distance and geographical distance (r = 0.638, p = 0.028) by the Mantel test, and two boundaries were found among the 12 Q. liaotungensis populations by the Barrier analysis, indicating that Q. liaotungensis populations existed isolated by geographical distance and physical barrier. Conclusion This study suggests that geographical isolation, physical barrier, climatic types, and natural hybridization promote the formation of genetic structures, which can contribute to future protection and genetic improvement of Q. liaotungensis.
Guo et al. (2021) Unraveling the genetic diversity and structure of Quercus liaotungensis population through analysis of microsatellite markers. PeerJ 9:e10922 https://doi.org/10.7717/peerj.10922
Meiogyne oligocarpa (Annonaceae), a new species from Yunnan, China
Meiogyne oligocarpa sp. nov. (Annonaceae) is described from Yunnan Province in Southwest China. It is easily distinguished from all previously described Meiogyne species by the possession of up to four carpels per flower, its bilobed, sparsely hairy stigma, biseriate ovules and cylindrical monocarps with a beaked apex. A phylogenetic analysis was conducted to confirm the placement of this new species within Meiogyne. Meiogyne oligocarpa represents the second species of Meiogyne in China: a key to the species of Meiogyne in China is provided to distinguish it from Meiogyne hainanensis. Paraffin sectioning was undertaken to study the anatomy of the corrugations on the inner petals of Meiogyne oligocarpa to verify whether they are glandular.
Xue et al. (2021) Meiogyne oligocarpa (Annonaceae), a new species from Yunnan, China. PeerJ 9:e10999 https://doi.org/10.7717/peerj.10999
A quantitative comparison of towed-camera and diver-camera transects for monitoring coral reefs
Novel tools and methods for monitoring marine environments can improve efficiency but must not compromise long-term data records. Quantitative comparisons between new and existing methods are therefore required to assess their compatibility for monitoring. Monitoring of shallow water coral reefs is typically conducted using diver-based collection of benthic images along transects. Diverless systems for obtaining underwater images (e.g. towed-cameras, remotely operated vehicles, autonomous underwater vehicles) are increasingly used for mapping coral reefs. Of these imaging platforms, towed-cameras offer a practical, low cost and efficient method for surveys but their utility for repeated measures in monitoring studies has not been tested. We quantitatively compare a towed-camera approach to repeated surveys of shallow water coral reef benthic assemblages on fixed transects, relative to benchmark data from diver photo-transects. Differences in the percent cover detected by the two methods was partly explained by differences in the morphology of benthic groups. The reef habitat and physical descriptors of the site—slope, depth and structural complexity—also influenced the comparability of data, with differences between the tow-camera and the diver data increasing with structural complexity and slope. Differences between the methods decreased when a greater number of images were collected per tow-camera transect. We attribute lower image quality (variable perspective, exposure and focal distance) and lower spatial accuracy and precision of the towed-camera transects as the key reasons for differences in the data from the two methods and suggest changes to the sampling design to improve the application of tow-cameras to monitoring.
Cresswell et al. (2021) A quantitative comparison of towed-camera and diver-camera transects for monitoring coral reefs. PeerJ 9:e11090 https://doi.org/10.7717/peerj.11090
Design and evaluation of a simulated wound management course for postgraduate year one surgery residents
Background It is vital to cover wound management knowledge and operations in the early stages of resident training. With this in mind, a simulated wound management course for postgraduate year one surgery residents (PGY1s) was designed and its effectiveness was evaluated. Methods A retrospective quasi-experimental method was used. PGY1s in 2014 constituted the control group, and PGY1s in 2015 and 2016 constituted the intervention group. The course given to the control group comprised didactic teaching followed by deliberate practice plus immediate personalized feedback. The newly designed course given to the intervention group was reconstructed and disassembled into four components according to the simulation-based mastery learning model, which were baseline test, interactive learning, basic skills practice, and reflective learning. The same performance assessments were used in the control and intervention group, including process measurement and outcome measurement. Results The process measurement showed that the intervention group’s scores were significantly higher in the “dissociation of subcutaneous tissue” and “quality of suturing and knots”. The outcome measurement showed that the accuracy of debridement was greatly improved and both key and total suture numbers were significantly higher in the intervention group. Conclusions Simulation-based mastery learning was incorporated into our proposed course framework, promoting the learning outcome of PGY1s. It has the potential to be adapted for other surgical training sites for residents in China.
Qi et al. (2021) Design and evaluation of a simulated wound management course for postgraduate year one surgery residents. PeerJ 9:e11104 https://doi.org/10.7717/peerj.11104