title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=709 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Differences in college students’ occupational dysfunction and mental health considering trait and state anxiety during the COVID-19 pandemic link: https://peerj.com/articles/13443 last-modified: 2022-05-19 description: BackgroundDue to the COVID-19 pandemic, university education has shifted from face-to-face classes to online and distance learning. Effects of exposure may manifest in terms of psychological, cognitive, or musculoskeletal impairments that affect an individual’s daily functioning and quality of life. There is a dearth of studies exploring anxiety states, occupational dysfunction, and mental health associated with the new standard of increased telecommunication. Accordingly, the present study aimed to identify the differences in occupational dysfunction, health literacy, positive and negative emotions, and stress response considering the anxiety states of college students during the COVID-19 pandemic. Another purpose is to identify relationships among the parameters such as occupational dysfunction and mental health.MethodsThis cross-sectional study included 358 students (average age: 18.5 years, age range: 18–29 years). Five tools were used: the State-Trait Anxiety Inventory (STAI), Classification and Assessment of Occupational Dysfunction (CAOD), European Health Literacy Survey Questionnaire (HLS-EU-Q47), Profile of Mood States 2nd Edition (POMS-2), and Stress Response Scale-18 (SRS-18). Based on the cutoff value of state and trait anxiety of the STAI, the participants were classified into four groups and compared using one-way analysis of variance and multiple comparison tests. The relationship between all parameters was analyzed using Pearson’s correlation coefficient.ResultsThe group with high trait anxiety and high state anxiety had the highest CAOD total score, Total Mood Disturbance score on the POMS-2, SRS-18 score, and scores on many sub-items of the three parameters. The prevalence of occupational dysfunction was 47% for university students, and there was a variation of from 19 to 61% in each group. The correlation coefficients of the state and trait anxiety scores of the STAI, Total Mood Disturbance score, and SRS-18 ranged from .64 to .75. Additionally, the correlation coefficient between the CAOD total score and these parameters ranged from .44 to .48.ConclusionThe prevalence of occupational dysfunction was highest in the group with high trait anxiety and high state anxiety, and occupational dysfunction, negative emotions, and stress responses were strongest in this group. Our findings point to potential areas for targeted support and interventions. creator: Yasuaki Kusumoto creator: Rieko Higo creator: Kanta Ohno uri: https://doi.org/10.7717/peerj.13443 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Kusumoto et al. title: Prevalence and richness of malaria and malaria-like parasites in wild birds from different biomes in South America link: https://peerj.com/articles/13485 last-modified: 2022-05-19 description: South America has different biomes with a high richness of wild bird species and Diptera vectors, representing an ideal place to study the influence of habitat on vector-borne parasites. In order to better understand how different types of habitats do or do not influence the prevalence of haemosporidians, we performed a new analysis of two published datasets comprising wild birds from the Brazilian Savanna (Cerrado) as well as wild birds from the Venezuelan Arid Zone. We investigated the prevalence and genetic diversity of haemosporidian parasites belonging to two genera: Plasmodium and Haemoproteus. We evaluated data from 676 wild birds from the Cerrado and observed an overall prevalence of 49%, whereas, in the Venezuelan Arid Zone, we analyzed data from 527 birds and found a similar overall prevalence of 43%. We recovered 44 lineages, finding Plasmodium parasites more prevalent in the Cerrado (15 Plasmodium and 12 Haemoproteus lineages) and Haemoproteus in the Venezuelan Arid Zone (seven Plasmodium and 10 Haemoproteus lineages). No difference was observed on parasite richness between the two biomes. We observed seven out of 44 haemosporidian lineages that are shared between these two distinct South American biomes. This pattern of parasite composition and prevalence may be a consequence of multiple factors, such as host diversity and particular environmental conditions, especially precipitation that modulate the vector’s dynamics. The relationship of blood parasites with the community of hosts in large and distinct ecosystems can provide more information about what factors are responsible for the variation in the prevalence and diversity of these parasites in an environment. creator: Daniela de Angeli Dutra creator: Nayara Belo creator: Erika M. Braga uri: https://doi.org/10.7717/peerj.13485 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 de Angeli Dutra et al. title: Association of multiple tumor markers with newly diagnosed gastric cancer patients: a retrospective study link: https://peerj.com/articles/13488 last-modified: 2022-05-19 description: BackgroundThe purpose of this paper was to explore the correlation between multiple tumor markers and newly diagnosed gastric cancer.MethodsWe selected 268 newly diagnosed patients with gastric cancer and 209 healthy subjects for correlation research. The detection of multiple tumor markers was based on protein chips and the results were statistically analyzed using SPSS.ResultsWe concluded that gastric cancer was significantly related to gender, age, alpha fetoprotein (AFP), carcinoembryonic antigen (CEA), carbohydrate antigen 125 (CA125), carbohydrate antigen 199 (CA199), and carbohydrate antigen 242 (CA242) positive levels (P < 0.001). After CA199 and CA242 were stratified by gender, the male odds ratio (OR) was 30.400 and 31.242, respectively, while the female OR was 3.424. After CA125 was stratified by age in patients over 54 years old with gastric cancer, the risk of occurrence in the CA125-positive population was 16.673 times that of the CA125-negative patients. Among patients 54 years old and younger, being CA125-positive was not a risk factor for gastric cancer (P = 0.082). AFP, CEA, CA125, CA199, and CA242 positive levels during the M1 stage were statistically significant when compared with the M0 stage and control group (P < 0.001), but the AFP (P = 0.045) and CA125 (P = 0.752) positive levels were not statistically significant when compared with the M0 stage and control group. The combined detection sensitivity of multiple tumor markers was 44.78%.ConclusionOur research shows that gastric cancer is associated with age, gender, and the positive levels of AFP, CEA, CA125, CA199, and CA242. The positive levels of AFP and CA125 were related to the distant metastasis of gastric cancer. To a certain extent, the combined detection sensitivity can be used for the initial screening of gastric cancer. creator: Xiaoyang Li creator: Sifeng Li creator: Zhenqi Zhang creator: Dandan Huang uri: https://doi.org/10.7717/peerj.13488 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Li et al. title: Seasonal and diel influences on bottlenose dolphin acoustic detection determined by whistles in a coastal lagoon in the southwestern Gulf of California link: https://peerj.com/articles/13246 last-modified: 2022-05-18 description: Marine mammals in subtropical coastal habitats are sentinels of the health of the ecosystem and offer important ecosystem services. They rely on prey that pursues feeding opportunities, while both avoid unfavorable conditions. In many cases, these predator-prey dynamics fluctuate seasonally and are regulated by lunar, tidal, and/or diel cycles (hour). However, these rhythmical patterns may vary under different seasonal conditions. Bottlenose dolphins (Tursiops truncatus) in the Ensenada de La Paz in Baja California Sur, Mexico, were detected acoustically over the course of an annual cycle on 21 separate occasions, covering 640 h from June 2017 to May 2019. The presence of bottlenose dolphins was examined using Generalized Additive Models (GAM) including variables that are related directly to their habitat (direct variables: hour, distance, depth) and to their prey (indirect variables: SST, moon phase and tides). Seasonal differences in the presence of bottlenose dolphins were influenced more by indirect variables (explained deviance: 34.8% vs. 37.7%). Hourly acoustic detections occurred less frequently when SST exceeded 27.4 °C (Aug–End of Nov.) and more frequently at moderate temperatures (22.7 °C to 26.3 °C) in May through July. Moreover, bottlenose dolphins were detected more frequently during waning and new moon phases, at the onset of flood and ebb tides, and during day (04:00 to 20:00). The seasonal differences in acoustic detections rates were highlighted by the global GAM and hierarchical clustering. The strong seasonal pattern indicated possible interactions with rhythmic pattern of bottlenose dolphins. Four candidate variables (SST, moon, tide, and hour) were tested for plausible interaction terms additional to their individual consideration, out of which only hour changed significantly between seasons. The patterns of presence likely increase feeding opportunities or may favor other behaviors such as socializing, resting, or nursing. These might prove responsible for the distinct occurrence and hourly patterns of bottlenose dolphins. creator: Marco F. W. Gauger creator: Eduardo Romero-Vivas creator: Myron A. Peck creator: Eduardo F. Balart creator: Javier Caraveo-Patiño uri: https://doi.org/10.7717/peerj.13246 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Gauger et al. title: Growth of Lahontan cutthroat trout from multiple sources re-introduced into Sagehen Creek, CA link: https://peerj.com/articles/13322 last-modified: 2022-05-18 description: Lahontan cutthroat trout Oncorhynchus clarkii henshawi have experienced massive declines in their native range and are now a threatened species under the US Endangered Species Act. A key management goal for this species is re-establishing extirpated populations using translocations and conservation hatcheries. In California USA, two broodstocks (Pilot Peak and Independence Lake) are available for reintroduction, in addition to translocations from wild and naturalized sources. Pilot Peak and Independence Lake fish are hatchery stocks derived from native fish from the Truckee River basin and used for recovery activities in the western Geographic Management Unit Areas only, specifically within the Truckee River basin. Yet suitability of these sources for re-introduction in different ecosystem types remains an open and important topic. We conducted growth experiments using Lahontan cutthroat trout stocked into Sagehen Creek, CA, USA. Experiments evaluated both available broodstocks and a smaller sample of fish translocated representing a naturalized population of unknown origin from a nearby creek. Fish from the Independence Lake source had significantly higher growth in weight and length compared to the other sources. Further, Independence Lake fish were the only stock that gained weight on average over the duration of the experiment. Our experiments suggest fish from the Independence Lake brood stock should be considered in reintroduction efforts. creator: Jonathan E. Stead creator: Virginia L. Boucher creator: Peter B. Moyle creator: Andrew L. Rypel uri: https://doi.org/10.7717/peerj.13322 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Stead et al. title: Handcycling with concurrent lower body low-frequency electromyostimulation significantly increases acute oxygen uptake: implications for rehabilitation and prevention link: https://peerj.com/articles/13333 last-modified: 2022-05-18 description: BackgroundAcute increases in exercise-induced oxygen uptake (V̇O2) is crucial for aerobic training adaptations and depends on how much muscle mass is involved during exercising. Thus, handcycling is per se limited for higher maximal oxygen uptakes (V̇O2max) due to restricted muscle involvement. Handcycling with additional and simultaneous application of low-frequency electromyostimulation (EMS) to the lower extremities might be a promising stimulus to improve aerobic capacity in disabled and rehabilitative populations.MethodTwenty-six healthy young adults (13 female, age: 23.4 ± 4.5 years, height: 1.77 ± 0.09 m, mass: 71.7 ± 16.7 kg) completed 4 ×10 minutes of sitting (SIT), sitting with concurrent EMS (EMS_SIT), handcycling (60 rpm, 1/2 bodyweight as resistance in watts) (HANDCYCLE) and handcycling with concurrent EMS of the lower extremities (EMS_HANDCYCLE). During EMS_SIT and EMS_HANDCYCLE, low frequency EMS (impulse frequency: 4Hz, impulse width: 350 µs, continuous stimulation) was applied to gluteal, quadriceps and calf muscles. The stimulation intensity was selected so that the perceived pain could be sustained for a duration of 10 minutes (gluteus: 80.0 ± 22.7 mA, quadriceps: 94.5 ± 20.5 mA, calves: 77.5 ± 19.1 mA).ResultsSignificant mode-dependent changes of V̇O2 were found (p < 0.001, ηp2 = 0.852). Subsequent post-hoc testing indicated significant difference between SIT vs. EMS_SIT (4.70 ± 0.75 vs. 10.61 ± 4.28 ml min−1 kg−1, p < 0.001), EMS_SIT vs. HANDCYCLE (10.61 ± 4.28 vs. 13.52 ± 1.40 ml min−1 kg−1, p = 0.005), and between HANDCYCLE vs. EMS_HANDCYCLE (13.52 ± 1.40 vs. 18.98 ± 4.89 ml min−1 kg−1, p = 0.001).ConclusionHandcycling with simultaneous lower body low-frequency EMS application elicits notably higher oxygen uptake during rest and moderately loaded handcycling and may serve as an additional cardiocirculatory training stimuli for improvements in aerobic capacity in wheelchair and rehabilitation settings. creator: Ludwig Rappelt creator: Steffen Held creator: Lars Donath uri: https://doi.org/10.7717/peerj.13333 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Rappelt et al. title: Embryonic development of the moon jellyfish Aurelia aurita (Cnidaria, Scyphozoa): another variant on the theme of invagination link: https://peerj.com/articles/13361 last-modified: 2022-05-18 description: BackgroundAurelia aurita (Scyphozoa, Cnidaria) is an emblematic species of the jellyfish. Currently, it is an emerging model of Evo-Devo for studying evolution and molecular regulation of metazoans’ complex life cycle, early development, and cell differentiation. For Aurelia, the genome was sequenced, the molecular cascades involved in the life cycle transitions were characterized, and embryogenesis was studied on the level of gross morphology. As a reliable representative of the class Scyphozoa, Aurelia can be used for comparative analysis of embryonic development within Cnidaria and between Cnidaria and Bilateria. One of the intriguing questions that can be posed is whether the invagination occurring during gastrulation of different cnidarians relies on the same cellular mechanisms. To answer this question, a detailed study of the cellular mechanisms underlying the early development of Aurelia is required.MethodsWe studied the embryogenesis of A. aurita using the modern methods of light microscopy, immunocytochemistry, confocal laser microscopy, scanning and transmission electron microscopy.ResultsIn this article, we report a comprehensive study of the early development of A. aurita from the White Sea population. We described in detail the embryonic development of A. aurita from early cleavage up to the planula larva. We focused mainly on the cell morphogenetic movements underlying gastrulation. The dynamics of cell shape changes and cell behavior during invagination of the archenteron (future endoderm) were characterized. That allowed comparing the gastrulation by invagination in two cnidarian species—scyphozoan A. aurita and anthozoan Nematostella vectensis. We described the successive stages of blastopore closure and found that segregation of the germ layers in A. aurita is linked to the ’healing’ of the blastopore lip. We followed the developmental origin of the planula body parts and characterized the planula cells’ ultrastructure. We also found that the planula endoderm consists of three morphologically distinct compartments along the oral-aboral axis.ConclusionsEpithelial invagination is a fundamental morphogenetic movement that is believed as highly conserved across metazoans. Our data on the cell shaping and behaviours driving invagination in A. aurita contribute to understanding of morphologically similar morphogenesis in different animals. By comparative analysis, we clearly show that invagination may differ at the cellular level between cnidarian species belonging to different classes (Anthozoa and Scyphozoa). The number of cells involved in invagination, the dynamics of the shape of the archenteron cells, the stage of epithelial-mesenchymal transition that these cells can reach, and the fate of blastopore lip cells may vary greatly between species. These results help to gain insight into the evolution of morphogenesis within the Cnidaria and within Metazoa in general. creator: Yulia Kraus creator: Boris Osadchenko creator: Igor Kosevich uri: https://doi.org/10.7717/peerj.13361 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Kraus et al. title: Hospital-level characteristics of the standardised mortality ratio for ischemic heart disease: a retrospective observational study using Japanese administrative claim data from 2012 to 2019 link: https://peerj.com/articles/13424 last-modified: 2022-05-18 description: BackgroundIschemic heart disease (IHD) is one of the leading causes of mortality worldwide and imposes a heavy burden on patients. Previous studies have indicated that the optimal care for IHD during hospitalisation may reduce the risk of in-hospital mortality. The standardised mortality ratio (SMR) is an indicator for assessing the risk-adjusted in-hospital mortality ratio based on case-mix. This indicator can crucially identify hospitals that can be changed to improve patient safety and the quality of care. This study aimed to determine the hospital-level characteristics of the SMR for IHD in Japan.MethodsThis study was designed as a retrospective observational study using the Japanese administrative claim data from 2012 to 2019. The data of all hospital admissions with a primary diagnosis of IHD (ICD-10, I20-I25) were used. Patients with complete variables data were included in this study. Hospitals with less than 200 IHD inpatients in each 2-year period were excluded. The SMR was defined as the ratio of the observed number of in-hospital deaths to the expected number of in-hospital deaths multiplied by 100.The observed number of in-hospital deaths was the sum of the actual number of in-hospital deaths at that hospital, and the expected number of in-hospital deaths was the sum of the probabilities of in-hospital deaths. Ratios of in-hospital mortality was risk-adjusted using multivariable logistic regression analyses. The c-statistic and Hosmer-Lemeshow test were used to evaluate the predictive accuracy of the logistic models. Changes in SMRs in each consecutive period were assessed using Spearman’s correlation coefficient.ResultsA total of 64,831 were admitted patients with IHD in 27 hospitals as complete submission data. The SMRs showed wide variation among hospitals, ranging from 35.4 to 197.6, and analysis models indicated good predictive ability with a c-statistic of 0.93 (95% CI [0.92–0.94]) and Hosmer-Lemeshow test of 0.30. The results of chi-square tests and t-tests for all variables to assess the association with in-hospital mortality were P < 0.001. In the analysis of trends in each consecutive period, the SMRs showed positive correlations.ConclusionsThis study denoted that the SMRs for IHD could be calculated using Japanese administrative claim data. The SMR for IHD might contribute to the development of more appropriate benchmarking systems for hospitals to improve quality of care. creator: Ryo Onishi creator: Yosuke Hatakeyama creator: Kunichika Matsumoto creator: Kanako Seto creator: Koki Hirata creator: Yinghui Wu creator: Tomonori Hasegawa uri: https://doi.org/10.7717/peerj.13424 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Onishi et al. title: Melatonin increases growth properties in human dermal papilla spheroids by activating AKT/GSK3β/β-Catenin signaling pathway link: https://peerj.com/articles/13461 last-modified: 2022-05-18 description: BackgroundMelatonin, a neurohormone, maybe involved in physiological processes, such as antioxidation, anti-inflammation, and hair growth. In the present study, we investigated the effects of melatonin on proliferation and intracellular signaling in DP cells using a three-dimensional (3D) spheroid culture system that mimics the in vivo hair follicle system.MethodsDP cells were incubated in monolayer (2D) and 3D spheroid culture systems. The expression levels of melatonin receptors in DP cells were analyzed using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blotting. The effect of melatonin on the hair-inductive property of DP cells was analyzed using a WST-1-based proliferation assay, determination of DP spheroid size, expression analysis of DP signature genes, and determination of β-catenin stabilization in DP cells. The AKT/GSK3β/β-catenin signaling pathway associated with melatonin-induced β-catenin stabilization in DP cells was investigated by analyzing changes in upstream regulator proteins, including AKT, GSK3β, and their phosphorylated forms.ResultsThe expression levels of the melatonin receptors were higher in human DP cells than in human epidermal keratinocytes and human dermal fibroblast cells. Comparing the expression level according to the human DP cell culture condition, melatonin receptor expression was upregulated in the 3D culture system compared to the traditional two-dimensional monolayer culture system. Cell viability analysis showed that melatonin concentrations up to 1 mM did not affect cell viability. Moreover, melatonin increased the diameter of DP cell 3D spheroids in a dose-dependent manner. Immunoblotting and qRT-PCR analysis revealed that melatonin upregulated the expression of hair growth-related genes, including alkaline phosphatase, bone morphogenetic protein 2, versican, and wingless-int 5A, in a melatonin receptor-dependent manner. Cell fractionation analysis showed that melatonin increased the nuclear localization of β-catenin. This result correlated with the increased transcriptional activation of T-cell factor/lymphoid enhancer factor-responsive luciferase induced by melatonin treatment. Interestingly, melatonin induced the phosphorylation of protein kinase B/AKT at serine 473 residue and GSK-3β at serine 9 residue. To determine whether AKT phosphorylation at serine 473 induced β-catenin nuclear translocation through GSK3β phosphorylation at serine 9, the PI3K/AKT inhibitor LY294002 was cotreated with melatonin. Immunoblotting showed that LY294002 inhibited melatonin-induced phosphorylation of GSK3β at serine 9 residue and β-catenin activation.ConclusionCollectively, this report suggests that melatonin promotes growth properties by activating the AKT/GSK3β/β-catenin signaling pathway through melatonin receptors. creator: Sowon Bae creator: Yoo Gyeong Yoon creator: Ji Yea Kim creator: In-Chul Park creator: Sungkwan An creator: Jae Ho Lee creator: Seunghee Bae uri: https://doi.org/10.7717/peerj.13461 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Bae et al. title: Bayesian estimation for the mean of delta-gamma distributions with application to rainfall data in Thailand link: https://peerj.com/articles/13465 last-modified: 2022-05-18 description: Precipitation and flood forecasting are difficult due to rainfall variability. The mean of a delta-gamma distribution can be used to analyze rainfall data for predicting future rainfall, thereby reducing the risks of future disasters due to excessive or too little rainfall. In this study, we construct credible and highest posterior density (HPD) intervals for the mean and the difference between the means of delta-gamma distributions by using Bayesian methods based on Jeffrey’s rule and uniform priors along with a confidence interval based on fiducial quantities. The results of a simulation study indicate that the Bayesian HPD interval based on Jeffrey’s rule prior performed well in terms of coverage probability and provided the shortest expected length. Rainfall data from Chiang Mai province, Thailand, are also used to illustrate the efficacies of the proposed methods. creator: Theerapong Kaewprasert creator: Sa-Aat Niwitpong creator: Suparat Niwitpong uri: https://doi.org/10.7717/peerj.13465 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Kaewprasert et al.