title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=694 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Study on soil-water characteristic curves in the profiles of collapsing walls of typical granite Benggang in southeast China link: https://peerj.com/articles/13526 last-modified: 2022-06-01 description: Benggang with steep collapsing walls is one of the worst soil erosion problems in South China. The collapse of walls is the most critical process in Benggang development. This is mainly due to the soil water properties. The soil water characteristic curve (SWCC) is a key indicator for analyzing soil moisture, but the SWCC and its mechanism of influence in collapsing walls remain obscure. A pressure plate meter was used for drying experiments to research the SWCCs of undisturbed soils of five layers (from top to bottom: red soil layer, transition layer I, sand soil layer, transition layer II and detrital layer) of two typical collapsing walls. The van Genuchten (VG) model can be fitted to the SWCCs for different layers (NSE ≥ 0.90). With increasing soil depth, the parameters a and θs first decreased and then increased, the parameters n first increased and then decreased, θr declined as the soil depth increased. These findings illustrate that soil water holding capacity decreases with increasing soil depth. The bottom of the soil is weak in water retention and water can easily reach saturation, resulting in a decline in soil stability, thus promoting soil collapse and finally inducing upper soil collapse. Furthermore, gravel content and particle morphology are factors that should not be neglected for SWCCs. The results of this study provide a theoretical basis for understanding the process of wall collapse in Benggang landforms in South China. creator: Liting Zhang creator: Shujun Sun creator: Mengqi Lin creator: Kaijun Feng creator: Yue Zhang creator: Jinshi Lin creator: Hongli Ge creator: Yanhe Huang creator: Fangshi Jiang uri: https://doi.org/10.7717/peerj.13526 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Zhang et al. title: The effect of listening to preferred music after a stressful task on performance and psychophysiological responses in collegiate golfers link: https://peerj.com/articles/13557 last-modified: 2022-06-01 description: BackgroundThis study explores whether listening to preferred music after a stressful situation affects putting and swinging performance, heart rate (HR), HR variability (HRV), and anxiety among amateur golfers.MethodsTwenty healthy amateur collegiate golfers voluntarily participated in this study (age 20.1 ± 1.17 yrs., height = 173.8 ± 7.74 cm, body weight = 72.35 ± 12.67 kg). Pre- and post-intervention HR and HRV measurements were taken, along with a self-report of the State-Trait Anxiety Inventory (STAI-S) and Triple Factor Anxiety Inventory (TFAI). Participants were exposed to a stressful situation through the Stroop Colour and Word Test (SCWT) and then instructed to perform three golf-practice sessions in a golf simulator, separated by 48–72 hours of recovery, under different conditions: control, pre-task music, and synchronised music.ResultsNo significant difference was identified between the experimental conditions for swinging (in terms of total distance (p = 0.116), carry distance (p = 0.608), speed of the ball (p = 0.819), and launch angle (p = 0.550) and putting performance (the number of successful putts on target (p > 0.05) and distance error between the target and ball (p = 0.122). No main effect for condition and time of intervention, as well as no interaction between these two factors was found for HR, HRV, and STAI-S (p = 0.116). However, the pre and post-intervention percentages of physiological items of the TFAI indicated a large, significant difference in synchronised music trial (p = 0.012, pre-task trial = −1.92% < control trial = 0% < synchronised trial = 4.58%).ConclusionsThe results imply that following a stressful situation, listening to preferred music before and/or during golf has no immediate effect on golf performance, anxiety, and psychophysiological responses in collegiate golfers. creator: Hung-Tsung Wang creator: Yung-Sheng Chen creator: Ghazi Rekik creator: Chia-Chen Yang creator: Mao-Sheng Lai creator: Hsia-Ling Tai uri: https://doi.org/10.7717/peerj.13557 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Wang et al. title: High gene flow in the silverlip pearl oyster Pinctada maxima between inshore and offshore sites near Eighty Mile Beach in Western Australia link: https://peerj.com/articles/13323 last-modified: 2022-05-31 description: An understanding of stock recruitment dynamics in fisheries is fundamental to successful management. Pinctada maxima is a bivalve mollusc widely distributed throughout the Indo-Pacific and is the main species targeted for cultured pearl and pearl shell production in Australia. Pearl production in Australia relies heavily on wild-caught individuals, the majority of which come from the Eighty Mile Beach region near Broome in Western Australia. In this study, we used a genotyping by sequencing approach to explore fine-scale patterns of genetic connectivity among inshore shallow and offshore deep populations of P. maxima near Eighty Mile Beach. Our results revealed high-levels of gene flow among inshore and offshore sites and no differences in genetic diversity between depths. Global estimates of genetic differentiation were low (FST = 0.006) but significantly different from zero, and pairwise estimates of genetic differentiation among sites were significant in only 3% of comparisons. Moreover, Bayesian clustering detected no separation of inshore and offshore sample sites, and instead showed all samples to be admixed among sites, locations and depths. Despite an absence of any clear spatial clustering among sites, we identified a significant pattern of isolation by distance. In a dynamic environment like Eighty Mile Beach, genetic structure can change from year-to-year and successive dispersal and recruitment events over generations likely act to homogenize the population. Although we cannot rule out the null hypothesis of panmixia, our data indicate high levels of dispersal and connectivity among inshore and offshore fishing grounds. creator: Luke Thomas creator: Karen J. Miller uri: https://doi.org/10.7717/peerj.13323 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Thomas and Miller title: Ferulic acid attenuates high glucose-induced apoptosis in retinal pigment epithelium cells and protects retina in db/db mice link: https://peerj.com/articles/13375 last-modified: 2022-05-31 description: BackgroundHerein, we aimed to present evidence that Ferulic acid (FA), a phenolic acid, can alleviate high glucose (HG)-induced retinal pigment epithelium (RPE) cell apoptosis and protect retina in db/db mice.MethodsARPE-19 cells (a human RPE cell line) were divided into four groups: control group; HG group (30 mmol/L glucose); HG+FA group (30 mmol/L glucose and 10 mmol/L FA). Cell viability and apoptosis were detected using CCK-8 and Annexin-5 staining, respectively. Apoptosis-related markers including P53, BAX and Bcl2 were examined by RT-qPCR, western blot and immunohistochemistry. Totally, 30 male db/db mice were randomly divided into db/db group (5 ml/kg saline) and FA group (0.05 g/kg FA). After treatment for 2 months, retinal samples were subjected to hematoxylin and eosin (H&E) and Masson staining. Moreover, immunofluorescence was used to detect apoptosis-related markers. Blood samples were collected for measuring cholesterol, triglyceride (TG), low-density lipoprotein (LDL) and high-density lipoprotein (HDL) levels.ResultsFA treatment markedly increased cell viability and suppressed cell apoptosis of ARPE-19 cells compared to the HG-exposed group. Furthermore, FA ameliorated the abnormal expression levels of P53, BAX and Bcl2 in HG-induced ARPE-19 cells. In animal models, FA attenuated pathological changes in the retina tissues of diabetic mice. Consistent with in vitro models, FA significantly ameliorated the expression of apoptosis-related markers in retina tissues. Biochemical test results showed that FA reduced hyperlipidemia in diabetic mice.ConclusionOur findings suggest that FA alleviates HG-induced apoptosis in RPE cells and protects retina in db/db mice, which can be associated with P53 and BAX inactivation and Bcl2 activation. creator: Dejun Zhu creator: Wenqing Zou creator: Xiangmei Cao creator: Weigang Xu creator: Zhaogang Lu creator: Yan Zhu creator: Xiaowen Hu creator: Jin Hu creator: Qing Zhu uri: https://doi.org/10.7717/peerj.13375 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Zhu et al. title: The application of plant growth-promoting rhizobacteria in Solanum lycopersicum production in the agricultural system: a review link: https://peerj.com/articles/13405 last-modified: 2022-05-31 description: Food safety is a significant challenge worldwide, from plantation to cultivation, especially for perishable products such as tomatoes. New eco-friendly strategies are needed, and beneficial microorganisms might be a sustainable solution. This study demonstrates bacteria activity in the tomato plant rhizosphere. Further, it investigates the rhizobacteria’s structure, function, and diversity in soil. Rhizobacteria that promote the growth and development of tomato plants are referred to as plant growth-promoting bacteria (PGPR). They form a series of associations with plants and other organisms in the soil through a mutualistic relationship where both parties benefit from living together. It implies the antagonistic activities of the rhizobacteria to deter pathogens from invading tomato plants through their roots. Some PGPR are regarded as biological control agents that hinder the development of spoilage organisms and can act as an alternative for agricultural chemicals that may be detrimental to the health of humans, animals, and some of the beneficial microbes in the rhizosphere soil. These bacteria also help tomato plants acquire essential nutrients like potassium (K), magnesium (Mg), phosphorus (P), and nitrogen (N). Some rhizobacteria may offer a solution to low tomato production and help tackle food insecurity and farming problems. In this review, an overview of soil-inhabiting rhizobacteria focused on improving the sustainable production of Solanum lycopersicum. creator: Afeez Adesina Adedayo creator: Olubukola Oluranti Babalola creator: Claire Prigent-Combaret creator: Cristina Cruz creator: Marius Stefan creator: Funso Kutu creator: Bernard R. Glick uri: https://doi.org/10.7717/peerj.13405 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Adedayo et al. title: Epidemiology of Helicobacter pylori in Australia: a scoping review link: https://peerj.com/articles/13430 last-modified: 2022-05-31 description: BackgroundHelicobacter pylori (H. pylori), a bacterium implicated in the development of peptic ulcer and gastric cancer, is estimated to infect around half the world’s population. Its prevalence in Australia is unclear. This scoping review aimed to evaluate all Australian literature providing estimates of the prevalence of H. pylori.MethodsAustralian studies examining H. pylori prevalence from 1982 onwards were eligible for inclusion. Medline, Embase and Scopus databases, and grey literature sources, were searched. Two independent reviewers undertook a two-stage screening process. Data were extracted by two independent reviewers using a pre-specified template.ResultsOf 444 identified studies, 75 were included in the review. H. pylori prevalence in Australian population-based studies (n = 8) ranged from 38.0% in 1991 to 15.1% in 2002; however, estimated prevalence across all non-clinical population studies in diverse sub-groups (n = 29) has varied dramatically. Decreased prevalence has been more marked in populations with gastrointestinal symptoms and conditions compared to non-clinical populations. Data on H. pyloriprevalence in vulnerable populations are lacking.ConclusionsThis is the first scoping review of Australian studies reporting H. pylori prevalence. A wide range of study designs, population groups, geographic regions, and diagnostic methods was included, involving data collected over a 50-year period (1969 to 2018). The summary of H. pylori prevalence estimates over time in this review points to a decrease in prevalence in Australia, particularly among populations with gastrointestinal symptoms and illnesses; however, it is unknown whether there is inequity in prevalence trends across vulnerable sub-groups of the Australian population. Future research and interventions supporting the health and wellbeing of vulnerable populations is required to ensure equitable health gains are made for all. creator: Jillian Congedi creator: Craig Williams creator: Katherine L. Baldock uri: https://doi.org/10.7717/peerj.13430 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Congedi et al. title: Population genetics and demography of the coral-killing cyanobacteriosponge, Terpios hoshinota, in the Indo-West Pacific link: https://peerj.com/articles/13451 last-modified: 2022-05-31 description: The first occurrence of the cyanobacteriosponge Terpios hoshinota was reported from coral reefs in Guam in 1973, but was only formally described in 1993. Since then, the invasive behavior of this encrusting, coral-killing sponge has been observed in many coral reefs in the West Pacific. From 2015, its occurrence has expanded westward to the Indian Ocean. Although many studies have investigated the morphology, ecology, and symbiotic cyanobacteria of this sponge, little is known of its population genetics and demography. In this study, a mitochondrial cytochrome oxidase I (COI) fragment and nuclear ribosomal internal transcribed spacer 2 (ITS2) were sequenced to reveal the genetic variation of T. hoshinota collected from 11 marine ecoregions throughout the Indo-West Pacific. Both of the statistical parsimony networks based on the COI and nuclear ITS2 were dominated by a common haplotype. Pairwise FST and Isolation-by-distance by Mantel test of ITS2 showed moderate gene flow existed among most populations in the marine ecoregions of West Pacific, Coral Triangle, and Eastern Indian Ocean, but with a restricted gene flow between these regions and Maldives in the Central Indian Ocean. Demographic analyses of most T. hoshinota populations were consistent with the mutation-drift equilibrium, except for the Sulawesi Sea and Maldives, which showed bottlenecks following recent expansion. Our results suggest that while long-range dispersal might explain the capability of T. hoshinota to spread in the IWP, stable population demography might account for the long-term persistence of T. hoshinota outbreaks on local reefs. creator: Savanna Wenhua Chow creator: Shashank Keshavmurthy creator: James Davis Reimer creator: Nicole de Voogd creator: Hui Huang creator: Jih-Terng Wang creator: Sen-Lin Tang creator: Peter J. Schupp creator: Chun Hong Tan creator: Hock-Chark Liew creator: Keryea Soong creator: Beginer Subhan creator: Hawis Madduppa creator: Chaolun Allen Chen uri: https://doi.org/10.7717/peerj.13451 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Chow et al. title: Spain is not different: teaching quantitative courses can also be hazardous to one’s career (at least in undergraduate courses) link: https://peerj.com/articles/13456 last-modified: 2022-05-31 description: Student evaluations of teaching (SETs) have become a widely used tool for assessing teaching in higher education. However, numerous investigations have shown that SETs are subject to multiple biases, one of which is particularly relevant, namely, the area of knowledge to which the subject belongs. This article aims to replicate the article by Uttl & Smibert (2017, https://doi.org/10.7717/peerj.3299) in a different educational context to verify whether the negative bias toward instructors who teach quantitative courses found by the authors in the US also appears in the Spanish university system. The study was conducted at the Business and Law School of the Universidad Pontificia Comillas, a private Spanish university, using two different samples. First, we analyzed undergraduate courses using a sample of 80,667 SETs in which 2,885 classes (defined as a single semester-long course taught by an individual instructor to a specific group of students), 488 instructors, and 322 different courses were evaluated over a time period of four academic years (2016/2017–2019/2020). Second, in the same period, 16,083 SETs corresponding to master’s degree courses were analyzed, which involved the study of 871 classes, 275 instructors, and 155 different courses. All the data included in the analysis were obtained from official university surveys developed by a team of professionals specialized in teaching quality responsible for ensuring the reliability of the information. At the degree level, the results show that despite the considerable cultural and temporal difference between the samples, the results are very similar to those obtained by Uttl & Smibert (2017, https://doi.org/10.7717/peerj.3299); i.e., professors teaching quantitative courses are far more likely to obtain worse SETs than instructors in other areas. There are hardly any differences at the master’s degree level, regardless of whether nearly 75% of master’s degree instructors also teach at the undergraduate level. This leads us to three different conclusions. (1) Evidence suggests that the reason for these differences is not due to faculty teaching quantitative courses being less effective than faculty teaching in some other fields. Our results indicate that the same instructor is evaluated very differently depending on whether he or she teaches at the undergraduate or master’s level. (2) It is essential to avoid comparisons of SETs between different areas of knowledge, at least at the undergraduate level. (3) A significant change in the use and interpretation of SETs is imperative, or its replacement by other evaluation mechanisms should be considered. If this does not occur, it is possible that in the future, there will be an adverse selection effect among professors of quantitative methods; i.e., only the worst professionals in quantitative methods will opt for teaching since the good professionals will prefer other jobs. creator: Jose Luis Arroyo-Barrigüete creator: Antonio Obregón creator: José María Ortiz-Lozano creator: Antonio Rua-Vieites uri: https://doi.org/10.7717/peerj.13456 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Arroyo-Barrigüete et al. title: Dramatic impact of future climate change on the genetic diversity and distribution of ecologically relevant Western Mediterranean Carex (Cyperaceae) link: https://peerj.com/articles/13464 last-modified: 2022-05-31 description: Anticipating the evolutionary responses of species to ongoing climate change is essential to propose effective management and conservation measures. The Western Mediterranean Basin constitutes one of the hotspots of biodiversity where the effects of climate change are expected to be more dramatic. Plant species with ecological relevance constitute ideal models to evaluate and predict the impact of climate change on ecosystems. Here we investigate these impacts through the spatio-temporal comparison of genetic diversity/structure (AFLPs), potential distribution under different future scenarios of climate change, and ecological space in two Western Mediterranean sister species of genus Carex. Both species are ecologically key in their riparian habitats, but display contrasting distribution patterns, with one widespread in the Iberian Peninsula and North Africa (C. reuteriana), while the other (C. panormitana) is a restricted, probably endangered, Central Mediterranean endemic. At present, we found a strong genetic structure driven by geography in both species, and lower values of genetic diversity and a narrower ecological space in C. panormitana than in C. reuteriana, while the allelic rarity was higher in the former than in C. reuteriana subspecies. Future projections predict an overall dramatic reduction of suitable areas for both species under all climate change scenarios, which could be almost total for C. panormitana. In addition, gene diversity was inferred to decrease in all taxa, with genetic structure reinforcing in C. reuteriana by the loss of admixture among populations. Our findings stress the need for a reassessment of C. panormitana conservation status under IUCN Red List criteria and the implementation of conservation measures. creator: Carmen Benítez-Benítez creator: María Sanz-Arnal creator: Malvina Urbani creator: Pedro Jiménez-Mejías creator: Santiago Martín-Bravo uri: https://doi.org/10.7717/peerj.13464 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Benítez-Benítez et al. title: A comparative metabolomics study of anthocyanins and taste components in Chinese bayberry (Morella rubra) with different flesh colors link: https://peerj.com/articles/13466 last-modified: 2022-05-31 description: The Chinese bayberry (Morella rubra Sieb. et Zucc.) is grown commercially in China and other Asian countries for its flavorful and appealing fruit. Here, two bayberry varieties differing in both color and flavor, namely, BDK (‘Baidongkui’) and DK (‘Dongkui’), in China were compared. A total of 18 anthocyanins, three proanthocyanidins, and 229 primary metabolites were identified in the pulp of the two varieties; these were analyzed and compared using ultra-performance liquid chromatography-tandem mass spectrometry. The DK pulp showed higher concentrations of all 18 anthocyanins compared with BDK, apart from peonidin-3,5-O-diglucoside which was not detected in BDK and which was responsible for the formation of pink pulp in BDK. Principal component analysis and cluster analysis of the primary metabolites indicated that the two bayberry varieties had distinct metabolite profiles with approximately 37% (85/229) of the primary metabolome being significantly different. Of these, 62 metabolites were down-regulated and 23 metabolites were up-regulated in BDK relative to DK. Our results suggested that the flavor of the BDK fruit was different from DK, which could be explained by the reduced saccharide, organic acid, amino acid, and proanthocyanidin contents. These findings enhance our understanding of the metabolites responsible for color and taste differences in the Chinese bayberry. creator: Qihua Lin creator: Qiuzhen Zhong creator: Zehuang Zhang uri: https://doi.org/10.7717/peerj.13466 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Lin et al.