title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=909 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Field and laboratory metabolism and thermoregulation in rhinoceros auklets link: https://peerj.com/articles/11460 last-modified: 2021-05-18 description: Seabirds spend most of their lives at sea, except when visiting their breeding sites. Since the thermal conductivity of water is 25 times higher than that of air, seabirds resting on water lose heat and expend a considerable amount of energy for thermoregulation. For example, rhinoceros auklet (Cerorhinca monocerata), a medium-sized (480–620 g) alcid, spends most of its time floating on the sea. In order to estimate the cost of this behavior in terms of their daily energy expenditure (DEE), we studied rhinoceros auklets breeding on Teuri Island, Hokkaido Japan. We measured their resting metabolic rate (RMR) in air and on water by respirometry, and estimated their DEE by the doubly labeled water method. While RMR on water did not vary significantly between 10 °C and 15 °C, it was significantly higher at 5 °C. Air temperature (5.0–20.0 °C) had no effect on RMR. The DEE of free-ranging auklets averaged 1,005.5 kJ day−1 (±130.2, n = 3). Our results indicate that RMRs are elevated for auklets resting on water, particularly below their lower critical temperature (LCT), compared with in air. Accordingly, spending time above their LCT on water at any time of year will provide enhanced benefits, particularly to seabirds such as rhinoceros auklets which rest a considerable amount of time on water. creator: Aika Umeyama creator: Yasuaki Niizuma creator: Masaki Shirai uri: https://doi.org/10.7717/peerj.11460 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2021 Umeyama et al. title: Microsatellite instability and Epstein-Barr virus combined with PD-L1 could serve as a potential strategy for predicting the prognosis and efficacy of postoperative chemotherapy in gastric cancer link: https://peerj.com/articles/11481 last-modified: 2021-05-18 description: BackgroundMicrosatellite instability (MSI) and Epstein-Barr virus (EBV)-positive molecular subtypes exhibit complex immune responses in gastric cancer (GC), and PD-L1 has emerged as a prognostic biomarker associated with the cancer immune microenvironment. This study aimed to determine the prognostic value of molecular subtypes and whether the addition of PD-L1 would accurately predict the prognosis and guide postoperative chemotherapy for GC patients.MethodsWe performed molecular subtyping of tissue microarray slides from 226 GC patients who were treated with radical gastrectomy. The MSI status and PD-L1 expression were evaluated through immunohistochemistry (IHC) and EBV status through situ hybridization. Multiplex polymerase chain reaction (PCR) was also performed on 50 cases to validate the accuracy of IHC in defining MSI status. Differences in overall survival (OS) were assessed using the Kaplan-Meier method, log-rank test and Cox proportional hazards regression model.ResultsAmong the 226 GC patients, 52 (23.2%) patients were classified as the MSI subtype, 11 (4.9%) were EBV+ subtype, and 161 (71.9%) were MSS (Microsatellite stable) /EBV− subtype according to TCGA analysis. Two patients were both positive for MSI and EBV infection. EBV+ cases showed higher PD-L1 positivity than MSI cases and MSS/EBV− cases (81.8% vs. 50.0% vs. 35.4%, P = 0.003). Compared with the non-MSS/EBV− (MSI or EBV+ cases) subgroup, GC patients with MSS/EBV− were associated with the worst outcomes (HR = 1.610, 95% CI [1.046–2.479], P = 0.031). MSS/EBV− GCs alone could benefit from postoperative chemotherapy (HR = 0.452, 95% CI [0.299–0.682], P < 0.001), and PD-L1-positive expression could also predict a better prognosis (HR = 0.612, 95% CI [0.389–0.962], P = 0.033) in this subgroup. Considering both chemotherapy efficacy and PD-L1 expression in the MSS/EBV− subgroup, chemotherapy could improve the prognosis for PD-L1-negative MSS/EBV− GCs (HR = 0.357, 95% CI [0.217–0.587], P < 0.001) but not PD-L1-positive MSS/EBV− GCs.ConclusionsMolecular subtyping combined with PD-L1 expression could serve as a potential strategy to better predict prognosis and guide postoperative chemotherapy of GC patients. creator: Na Yang creator: Yanhua Wu creator: Meishan Jin creator: Zhifang Jia creator: Yueqi Wang creator: Donghui Cao creator: Lili Qin creator: Xueying Wang creator: Min Zheng creator: Xueyuan Cao creator: Jing Jiang uri: https://doi.org/10.7717/peerj.11481 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2021 Yang et al. title: An integrative monograph of Carex section Schoenoxiphium (Cyperaceae) link: https://peerj.com/articles/11336 last-modified: 2021-05-17 description: Carex section Schoenoxiphium (Cariceae, Cyperaceae) is endemic to the Afrotropical biogeographic region and is mainly distributed in southern and eastern Africa, with its center of diversity in eastern South Africa. The taxon was formerly recognized as a distinct genus and has a long history of taxonomic controversy. It has also an important morphological and molecular background in particular dealing with the complexity of its inflorescence and the phylogenetic relationships of its species. We here present a fully updated and integrative monograph of Carex section Schoenoxiphium based on morphological, molecular and cytogenetic data. A total of 1,017 herbarium specimens were examined and the majority of the species were studied in the field. Previous molecular phylogenies based on Sanger-sequencing of four nuclear and plastid DNA regions and RAD-seq were expanded. For the first time, chromosome numbers were obtained, with cytogenetic counts on 44 populations from 15 species and one hybrid. Our taxonomic treatment recognizes 21 species, one of them herein newly described (C. gordon-grayae). Our results agree with previous molecular works that have found five main lineages in Schoenoxiphium. We provide detailed morphological descriptions, distribution maps and analytical drawings of all accepted species in section Schoenoxiphium, an identification key, and a thorough nomenclatural survey including 19 new typifications and one nomen novum. creator: Modesto Luceño creator: Tamara Villaverde creator: José Ignacio Márquez-Corro creator: Rogelio Sánchez-Villegas creator: Enrique Maguilla creator: Marcial Escudero creator: Pedro Jiménez-Mejías creator: Manuel Sánchez-Villegas creator: Monica Miguez creator: Carmen Benítez-Benítez creator: A. Muthama Muasya creator: Santiago Martín-Bravo uri: https://doi.org/10.7717/peerj.11336 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2021 Luceño et al. title: Trp-574-Leu mutation in wild mustard (Sinapis arvensis L.) as a result of als inhibiting herbicide applications link: https://peerj.com/articles/11385 last-modified: 2021-05-17 description: Wheat is one of the most important crops grown all around the world. Weeds cause significant yield loss and damage to wheat and their control is generally based on herbicide application. Regular use leads to herbicide resistance in weeds. This study aims to reveal molecular detection of Sinapis arvensis resistance mutation against ALS inhibiting herbicides. For this purpose, survey studies have been carried out in wheat growing areas in Amasya, Çorum, Tokat, and Yozgat provinces and wild mustard seeds have been collected from 310 different fields. According to bioassay tests with tribenuron-methyl, 13 of these populations, have not been affected by the registered dose of herbicide. When survived populations were subjected to dose-effect study and herbicides were applied at 26-fold, the highest and lowest resistance coefficients were determined as 7.2 (A-007) and 1.02 (T-034) respectively. In addition, B domain region from ALS gene was amplified and analyzed in molecular studies to determine point mutation in wild mustard against ALS herbicides. The PCR products were sequenced and target-site mutation to Leucine was observed at Trp-574 amino acide. In the study, point mutation in Trp-574 amino acide and Trp-574 Leu mutation in Sinapis arvensis have been detected for the first time in Turkey. creator: Bahadir Sin creator: İzzet Kadıoglu uri: https://doi.org/10.7717/peerj.11385 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2021 Sin et al. title: Group B Streptococcus and the vaginal microbiome among pregnant women: a systematic review link: https://peerj.com/articles/11437 last-modified: 2021-05-17 description: BackgroundVaginal microbiome studies frequently report diversity metrics and communities of microbiomes associated with reproductive health outcomes. Reports of Streptococcus agalactiae (also known as Group B Streptococcus or GBS), the leading cause of neonatal infectious morbidity and mortality, are notably lacking from the studies of the vaginal microbiome, despite being a known contributor to preterm birth and other complications. Therefore, the purpose of this systematic review was to explore the frequency of GBS reporting in vaginal microbiome literature pertaining to pregnancy and to examine methodological bias that contributes to differences in species and genus-level microbiome reporting. Lack of identification of GBS via sequencing-based approaches due to methodologic or reporting bias may result incomplete understanding of bacterial composition during pregnancy and subsequent birth outcomes.MethodologyA systematic review was conducted following the PRISMA guideline. Three databases (PubMed, CINAHL, and Web of Science) were used to identify papers for review based on the search terms “vaginal microbiome”, “pregnancy”, and “16S rRNA sequencing”. Articles were evaluated for methods of DNA extraction and sequencing, 16S region, taxonomy classification database, number of participants or vaginal specimens, and pregnancy trimester.ResultsForty-five research articles reported employing a metagenomic approach or 16S approach for vaginal microbiome analysis during pregnancy that explicitly reported taxonomic composition and were included in this review. Less than 30% of articles reported the presence of GBS (N = 13). No significant differences in methodology were identified between articles that reported versus did not report GBS. However, there was large variability across research methods used for vaginal microbiome analysis and species-level bacterial community reporting.ConclusionConsiderable differences in study design and data formatting methods may contribute to underrepresentation of GBS, and other known pathogens, in existing vaginal microbiome literature. Previous studies have identified considerable variation in methodology across vaginal microbiome studies. This study adds to this body of work because in addition to laboratory or statistical methods, how results and data are shared (e.g., only analyzing genus level data or 20 most abundant microbes), may hinder reproducibility and limit our understanding of the influence of less abundant microbes. Sharing detailed methods, analysis code, and raw data may improve reproducibility and ability to more accurately compare microbial communities across studies. creator: Sungju Lim creator: Shilpa Rajagopal creator: Ye Ryn Jeong creator: Dumebi Nzegwu creator: Michelle L. Wright uri: https://doi.org/10.7717/peerj.11437 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2021 Lim et al. title: Machine learning in dental, oral and craniofacial imaging: a review of recent progress link: https://peerj.com/articles/11451 last-modified: 2021-05-17 description: Artificial intelligence has been emerging as an increasingly important aspect of our daily lives and is widely applied in medical science. One major application of artificial intelligence in medical science is medical imaging. As a major component of artificial intelligence, many machine learning models are applied in medical diagnosis and treatment with the advancement of technology and medical imaging facilities. The popularity of convolutional neural network in dental, oral and craniofacial imaging is heightening, as it has been continually applied to a broader spectrum of scientific studies. Our manuscript reviews the fundamental principles and rationales behind machine learning, and summarizes its research progress and its recent applications specifically in dental, oral and craniofacial imaging. It also reviews the problems that remain to be resolved and evaluates the prospect of the future development of this field of scientific study. creator: Ruiyang Ren creator: Haozhe Luo creator: Chongying Su creator: Yang Yao creator: Wen Liao uri: https://doi.org/10.7717/peerj.11451 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2021 Ren et al. title: The impact of COVID-19 pandemic on the level of depression among health care workers: cross-sectional study link: https://peerj.com/articles/11469 last-modified: 2021-05-17 description: BackgroundThe outbreak of the novel Corona Virus Infectious Disease 2019 (COVID-19) has spread rapidly to many countries leading to thousands of deaths globally. The burden of this pandemic has affected the physical and mental health of the frontline health care workers (HCWs) who are exposed to high risk of infection and psychological stressors.AimsThe aim is to measure the level of depression among healthcare workers in Saudi Arabia during COVID-19 pandemic to establish interventional strategies.MethodA descriptive cross-sectional study was used to conduct the current study. The data of this study was recruited between 15 June and 15 July 2020 from healthcare providers who work in both public and private healthcare sectors in Riyadh and Eastern province in Saudi Arabia utilizing a self-administered questionnaire. The study was approved by the Institutional Review Board at Dr. Sulaiman Al Habib Medical Group (IRB Log No. RC20.06.88-2). Data were collected by using The Zung Self-Rating Depression Scale SDS. A total of 900 healthcare providers working in the healthcare setting during COVID-19 pandemic were invited to participate in the study. A total of 650 healthcare providers participated in the study by completing and submitting the survey.ResultsAlmost 30% suffered from depression which can be divided into three categories; mild depression (26.2%), moderate/major (2.5%) and severe/extreme (0.8%). The finding shows that the level of depression among respondents at the age range of 31–40 years old was significantly higher than the level of depression among respondents with the age above 50 years old. Non-Saudi healthcare workers experienced more depression than Saudi workers. It also shows how nurses suffered from depression compared to their physician colleagues. Those who did not suffer from sleeping disorder perceived more depression as compared to those who are having sleeping disorder.ConclusionIt is recommended that health care facilities should implement strategies to reduce the prevalence of mental health problems among healthcare providers and eventually it will improve their performance in provision of safe and high-quality care for patients. creator: Abbas Al Mutair creator: Alya Al Mutairi creator: Zainab Ambani creator: Abbas Shamsan creator: Sana AlMahmoud creator: Saad Alhumaid uri: https://doi.org/10.7717/peerj.11469 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2021 Al Mutair et al. title: Longer leisure walking time is associated with positive self-rated health among adults and older adults: a Brazilian nationwide study link: https://peerj.com/articles/11471 last-modified: 2021-05-17 description: BackgroundTo verify the association between weekly leisure walking time and positive self-rated health in the Brazilian adult and elderly population.MethodsThis cross-sectional study used information collected in 2019 across all regions of Brazil. This study included 25,785 people aged ≥ 18 years (mean = 51.6; standard deviation = 18.0) from all capitals of the Brazilian states who reported practicing walking as physical activity during leisure time. Self-rated health was the dependent variable (positive or negative). The leisure walking time/week was the main exposure and it was categorized in “150 minutes/week”, “150–299 minutes/week” and “≥ 300 minutes/week”. We used binary logistic regression to estimate odds ratio (OR) and 95% confidence intervals (95% CI) that was adjusted for relevant covariates.ResultsWe found that individuals who reported leisure walking for a period from 150 to 299 minutes/week and those who reported walking for a period ≥ 300 minutes/week were respectively 28% (OR = 1.28. 95% CI [1.10–1.48]) and 52% (OR = 1.52. 95% CI [1.27–1.82]) more likely of perceiving their health positively compared to those who reported walking for a period < 150 minutes/week. Individuals who reported leisure walking time <150 minutes/week had 72.3% (95% CI [70.4–74.1]) probability of perceiving their health positively. Individuals who reported leisure walking time from 150 to 299 minutes/week had 76.6% (95% CI [75.0 –78.3) probability of perceiving their health positively. On the other hand, individuals who reported leisure walking time ≥ 300 minutes/week had 79.2% probability (95% CI [77.1–81.4]) of perceiving their health positively.ConclusionLonger leisure walking time was associated with positive self-rated health among adults and older adults in Brazil. creator: Diego Augusto Santos Silva uri: https://doi.org/10.7717/peerj.11471 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2021 Silva title: Multi-scale analysis of the characteristics of the changing landscape of the typical mountainous region of Southwest China over the past 40 years link: https://peerj.com/articles/10923 last-modified: 2021-05-14 description: ContextYunnan Province is an important ecological security barrier in China. This study investigated the temporal and spatial changes to landscape ecology and is of great significance for guiding landscape protection and future socio-economic development.ObjectivesTo analyze the temporal and spatial changes of the landscape patterns at the county, river basin, and provincial levels, and clarify and describe the temporal and spatial differentiation characteristics of the landscape patterns in Yunnan Province.MethodsBased on landscape ecology, GIS spatial analysis, and spatio-temporal change analysis, nine landscape pattern indices, and spatial autocorrelation for different years, were calculated.ResultsThe landscape of Yunnan Province has evolved as a whole toward isolation. The indices of separation and fragmentation changed significantly from 2010 to 2015. From 2015 to 2018 the rate of fragmentation decreased. Fragmentation in the Nu Jiang and Irrawaddy River basins was less than in other basins. The landscape patterns of the Jinsha and Pearl River basins were relatively fragmented due to human activity, socioeconomic development, and utilization. The differences between the Lancang and Red River Basins were relatively small and at an intermediate level.ConclusionsSpatial autocorrelation analysis indicated that there are three areas with typical clusters, namely the Hengduan Mountains where the degree of fragmentation of the landscape was low, while landscape connectivity and aggregation were high. The subtropical region of Southern Yunnan displayed high landscape heterogeneity, a complex shape index, and high connectivity and sprawl. Central Yunnan exhibited a fragmented landscape with poor connectivity and aggregation. These three regions correspond with “the three screens and two belts” in the Main Functional Planning Area of Yunnan Province. creator: Fang Liu creator: Wanbin Wang creator: Jinliang Wang creator: Xingzi Zhang creator: Jing Ren creator: Yuexiong Liu uri: https://doi.org/10.7717/peerj.10923 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2021 Liu et al. title: Consequences of herbal mixture supplementation on milk performance, ruminal fermentation, and bacterial diversity in water buffaloes link: https://peerj.com/articles/11241 last-modified: 2021-05-14 description: This study was aimed to evaluate the potential of a herbal mixture (HM) to improve production performance, rumen fermentation, and milk fatty acid profile in water buffaloes. Sixteen Murrah buffaloes (in four groups) were fed for 10 weeks with the same basal diet supplemented with 0 (control); 20 (HM20), 30 (HM30), and 40 (HM40) g/buffalo per day. The herbal mixture contained an equal quantity of black pepper (fruit), ginger (tubers), cinnamon (bark), peppermint (leaves), ajwain (seeds) and garlic (bulbs). After two weeks of adaptation, daily milk yield, and weekly milk composition were recorded. On the last day of the experiment, rumen contents were collected to determine rumen fermentation parameters and bacterial diversity through 16S rRNA sequencing. Results revealed no effect of treatment on dry matter intake (DMI), rumen fermentation parameters, and daily milk yield. However, milk fat (%) showed a tendency to increase (p = 0.07) in HM20 as compared with the control group. A significant increase in mono and polyunsaturated fatty acids (C14:1, C16:1, C18:2n6 and C18:3) whereas a decrease in saturated fatty acids (C18:0) in milk was observed in HM20 as compared with the control group. No significant change in bacterial diversity parameters (alpha and beta diversity) was observed in response to the treatment. Despite the substantial variation observed in the relative abundance of bacteria among treatment groups, no significant effect of treatment was observed when compared with the control group. Correlation analysis revealed several positive and negative correlations of rumen bacteria with rumen volatile fatty acids (VFA) and milk yield traits. Bacterial genera including Succinivibrionaceae, Butyrivibrio, Pseudobutyrivibrio, and Lachnospiraceae showed a positive correlation with VFA and milk yield traits. Overall, we observed 52 positive and 10 negative correlations of rumen bacteria with milk fatty acid contents. Our study revealed the potential of the herbal mixture at a lower supplemental level (20 g/day) to increase milk fat (%) and unsaturated fatty acid content in buffalo. creator: Faizul Hassan creator: Zhenhua Tang creator: Hossam M. Ebeid creator: Mengwei Li creator: Kaiping Peng creator: Xin Liang creator: Chengjian Yang uri: https://doi.org/10.7717/peerj.11241 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2021 Hassan et al.