title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=1004 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Hissing of geese: caller identity encoded in a non-vocal acoustic signal link: https://peerj.com/articles/10197 last-modified: 2020-11-24 description: Non-vocal, or unvoiced, signals surprisingly have received very little attention until recently especially when compared to other acoustic signals. Some sounds made by terrestrial vertebrates are produced not only by the larynx but also by the syrinx. Furthermore, some birds are known to produce several types of non-syrinx sounds. Besides mechanical sounds produced by feathers, bills and/or wings, sounds can be also produced by constriction, anywhere along the pathway from the lungs to the lips or nostrils (in mammals), or to the bill (in birds), resulting in turbulent, aerodynamic sounds. These noises often emulate whispering, snorting or hissing. Even though hissing sounds have been studied in mammals and reptiles, only a few studies have analyzed hissing sounds in birds. Presently, only the hissing of small, nesting passerines as a defense against their respective predators have been studied. We studied hissing in domestic goose. This bird represents a ground nesting non-passerine bird which frequently produces hissing out of the nest in comparison to passerines producing hissing during nesting in holes e.g., parids. Compared to vocally produced alarm calls, almost nothing is known about how non-vocal hissing sounds potentially encode information about a caller’s identity. Therefore, we aimed to test whether non-vocal air expirations can encode an individual’s identity similar to those sounds generated by the syrinx or the larynx. We analyzed 217 hissing sounds from 22 individual geese. We calculated the Potential for Individual Coding (PIC) comparing the coefficient of variation both within and among individuals. In addition, we conducted a series of 15 a stepwise discriminant function analysis (DFA) models. All 16 acoustic variables showed a higher coefficient of variation among individuals. Twelve DFA models revealed 51.2–54.4% classification result (cross-validated output) and all 15 models showed 60.8–68.2% classification output based on conventional DFA in comparison to a 4.5% success rate when classification by chance. This indicates the stability of the DFA results even when using different combinations of variables. Our findings showed that an individual’s identity could be encoded with respect to the energy distribution at the beginning of a signal and the lowest frequencies. Body weight did not influence an individual’s sound expression. Recognition of hissing mates in dangerous situations could increase the probability of their surviving via a more efficient anti-predator response. creator: Richard Policht creator: Artur Kowalczyk creator: Ewa Łukaszewicz creator: Vlastimil Hart uri: https://doi.org/10.7717/peerj.10197 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Policht et al. title: Habitat conditions strongly affect macro- and microelement concentrations in Taraxacum microspecies growing on coastal meadows along a soil salinity gradient link: https://peerj.com/articles/10233 last-modified: 2020-11-24 description: Wild greens can contribute to the human diet as an important source of essential nutrients and drugs. Since environmental factors, including soil properties, may affect the chemical composition of plants, it is necessary among others to assess various habitats in terms of their usefulness for wild plant harvesting and to study impact of environmental factors on the qualitative and quantitative chemical composition of plants. This study was aimed at (1) examining the mineral composition of leaves of three dandelion microspecies, (2) determining the variability of macro- and microelement concentrations in dandelion leaves from populations growing on salty, brackish and non-saline coastal meadows, and (3) assessing the effects of different habitat conditions on the mineral composition of dandelion leaves. It was hypothesized that dandelion microspecies would differ significantly in the mineral composition of leaves. It was also expected that soil conditions would significantly affect nutrient concentrations in dandelion leaves, with soil salinity being the most important factor that differentiated studied populations. Leaves of three dandelion microspecies (Taraxacum balticum, T. nordstedtii, T. haematicum) were harvested in Baltic costal grasslands, along the soil salinity gradient, to determine macro- and microelement concentrations. Soil samples collected in the closest vicinity of the harvested plants showed the study sites to differ significantly in their soil properties. Moderately saline and organic soils, rich in potassium (K), magnesium (Mg), and calcium (Ca), supported T. balticum. Moderately or weakly saline and non-saline, organic or mineral soils, with lower median values of K, Mg, and Ca, were typical of T. nordstedtii sites, while the lowest median values of all the soil properties studied were found for T. haematicum sites. Our results proved that dandelion microspecies differ significantly in the mineral composition of their leaves. The between-microspecies differences were significant for all the macroelements except magnesium and all the microelements except molybdenum. Most of the macro- and microelements in leaves of the dandelion microspecies correlated positively and significantly with the soil properties, the strongest correlations being found for soil salinity and the leaf Na, Mn, Ca, Fe, K and Zn contents, followed by soil pH and the leaf Na, Mn, Fe, K, Ca, Zn and Mg. Moreover, the impact of soil properties on the mineral contents in leaves of the dandelions we examined seems to be stronger than the genetic differences between dandelion microspecies. Results of our studies on mineral composition of dandelion leaves lend support to the contention that wild greens provide essential mineral nutrients to the diet. Coastal meadows, fed by the brackish water of the Baltic Sea and free of anthropogenic pollution, are a good habitat to collect wild greens from. creator: Beata Bosiacka creator: Monika Myśliwy creator: Mateusz Bosiacki uri: https://doi.org/10.7717/peerj.10233 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Bosiacka et al. title: Spatially resolved dendritic integration: towards a functional classification of neurons link: https://peerj.com/articles/10250 last-modified: 2020-11-24 description: The vast tree-like dendritic structure of neurons allows them to receive and integrate input from many neurons. A wide variety of neuronal morphologies exist, however, their role in dendritic integration, and how it shapes the response of the neuron, is not yet fully understood. Here, we study the evolution and interactions of dendritic spikes in excitable neurons with complex real branch structures. We focus on dozens of digitally reconstructed illustrative neurons from the online repository NeuroMorpho.org, which contains over 130,000 neurons. Yet, our methods can be promptly extended to any other neuron. This approach allows us to estimate and map specific and heterogeneous patterns of activity observed across extensive dendritic trees with thousands of compartments. We propose a classification of neurons based on the location of the soma (centrality) and the number of branches connected to the soma. These are key topological factors in determining the neuron’s energy consumption, firing rate, and the dynamic range, which quantifies the range in synaptic input rate that can be reliably encoded by the neuron’s firing rate. Moreover, we find that bifurcations, the structural building blocks of complex dendrites, play a major role in increasing the dynamic range of neurons. Our results provide a better understanding of the effects of neuronal morphology in the diversity of neuronal dynamics and function. creator: Christoph Kirch creator: Leonardo L. Gollo uri: https://doi.org/10.7717/peerj.10250 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2020 Kirch and Gollo title: DPM1 expression as a potential prognostic tumor marker in hepatocellular carcinoma link: https://peerj.com/articles/10307 last-modified: 2020-11-24 description: BackgroundAltered glycosylation of proteins contributes to tumor progression. Dolichol phosphate mannose synthase (DPMS), an essential mannosyltransferase, plays a central role in post-translational modification of proteins, including N-linked glycoproteins, O-mannosylation, C-mannosylation and glycosylphosphatidylinositol anchors synthesis. Little is known about the function of DPMS in liver cancer.MethodsThe study explored the roles of DPMS in the prognosis of hepatocellular carcinoma using UALCAN, Human Protein Atlas, GEPIA, cBioPortal and Metascape databases. The mRNA expressions of DPM1/2/3 also were detected by quantitative real-time PCR experiments in vitro.ResultsThe transcriptional and proteinic expressions of DPM1/2/3 were both over-expressed in patients with hepatocellular carcinoma. Over-expressions of DPMS were discovered to be dramatically associated with clinical cancer stages and pathological tumor grades in hepatocellular carcinoma patients. In addition, higher mRNA expressions of DPM1/2/3 were found to be significantly related to shorter overall survival in liver cancer patients. Futhermore, high genetic alteration rate of DPMS (41%) was also observed in patients with liver cancer, and genetic alteration in DPMS was associated with shorter overall survival in hepatocellular carcinoma patients. We also performed quantitative real-time PCR experiments in human normal hepatocytes and hepatoma cells to verify the expressions of DPM1/2/3 and results showed that the expression of DPM1 was significantly increased in hepatoma cells SMMC-7721 and HepG2.ConclusionsTaken together, these results suggested that DPM1 could be a potential prognostic biomarker for survivals of hepatocellular carcinoma patients. creator: Ming Li creator: Shengli Xia creator: Ping Shi uri: https://doi.org/10.7717/peerj.10307 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Li et al. title: HIV-1 promoter is gradually silenced when integrated into BACH2 in Jurkat T-cells link: https://peerj.com/articles/10321 last-modified: 2020-11-24 description: BackgroundThe persistence of the latent HIV-1 reservoir is a major obstacle to curing HIV-1 infection. HIV-1 integrates into the cellular genome and some targeted genomic loci are frequently detected in clonally expanded latently HIV-1 infected cells, for instance, the gene BTB domain and CNC homology 2 (BACH2).MethodsWe investigated HIV-1 promoter activity after integration into specific sites in BACH2 in Jurkat T-cells. The HIV-1-based vector LTatCL[M] contains two fluorophores: (1) Cerulean, which reports the activity of the HIV-1 promoter and (2) mCherry driven by a constitutive promotor and flanked by genetic insulators. This vector was inserted into introns 2 and 5 of BACH2 of Jurkat T-cells via CRISPR/Cas9 technology in the same and convergent transcriptional orientation of BACH2, and into the genomic safe harbour AAVS1. Single cell clones representing active (Cerulean+/mCherry+) and inactive (Cerulean–/mCherry+) HIV-1 promoters were characterised.ResultsUpon targeted integration of the 5.3 kb vector LTatCL[M] into BACH2, the HIV-1 promoter was gradually silenced as reflected by the decrease in Cerulean expression over a period of 162 days. Silenced HIV-1 promoters could be reactivated by TNF-α and Romidepsin. This observation was independent of the targeted intron and the transcriptional orientation. BACH2 mRNA and protein expression was not impaired by mono-allelic integration of LTatCL[M].ConclusionSuccessful targeted integration of the HIV-1-based vector LTatCL[M] allows longitudinal analyses of HIV-1 promoter activity. creator: Anne Inderbitzin creator: Yik Lim Kok creator: Lisa Jörimann creator: Audrey Kelley creator: Kathrin Neumann creator: Daniel Heinzer creator: Toni Cathomen creator: Karin J. Metzner uri: https://doi.org/10.7717/peerj.10321 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2020 Inderbitzin et al. title: Wnt16 signaling promotes osteoblast differentiation of periosteal derived cells in vitro and in vivo link: https://peerj.com/articles/10374 last-modified: 2020-11-24 description: BackgroundPeriosteum plays critical roles in de novo bone formation and fracture repair. Wnt16 has been regarded as a key regulator in periosteum bone formation. However, the role of Wnt16 in periosteum derived cells (PDCs) osteogenic differentiation remains unclear. The study goal is to uncover whether and how Wnt16 acts on the osteogenesis of PDCs.MethodsWe detected the variation of Wnt16 mRNA expression in PDCs, which were isolated from mouse femur and identified by flow cytometry, cultured in osteogenic medium for 14 days, then knocked down and over-expressed Wnt16 in PDCs to analysis its effects in osteogenesis. Further, we seeded PDCs (Wnt16 over-expressed/vector) in β-tricalcium phosphate cubes, and transplanted this complex into a critical size calvarial defect. Lastly, we used immunofluorescence, Topflash and NFAT luciferase reporter assay to study the possible downstream signaling pathway of Wnt16.ResultsWnt16 mRNA expression showed an increasing trend in PDCs under osteogenic induction for 14 days. Wnt16 shRNA reduced mRNA expression of Runx2, collage type I (Col-1) and osteocalcin (OCN) after 7 days of osteogenic induction, as well as alizarin red staining intensity after 21days. Wnt16 also increased the mRNA expression of Runx2 and OCN and the protein production of Runx2 and Col-1 after 2 days of osteogenic stimulation. In the orthotopic transplantation assay, more bone volume, trabecula number and less trabecula space were found in Wnt16 over-expressed group. Besides, in the newly formed tissue Brdu positive area was smaller and Col-1 was larger in Wnt16 over-expressed group compared to the control group. Finally, Wnt16 upregulated CTNNB1/β-catenin expression and its nuclear translocation in PDCs, also increased Topflash reporter luciferase activity. By contrast, Wnt16 failed to increase NFAT reporter luciferase activity.ConclusionTogether, Wnt16 plays a positive role in regulating PDCs osteogenesis, and Wnt16 may have a potential use in improving bone regeneration. creator: Ying Jin creator: Xiaoyan Sun creator: Fang Pei creator: Zhihe Zhao creator: Jeremy Mao uri: https://doi.org/10.7717/peerj.10374 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Jin et al. title: Modelling the effects of Spartina alterniflora invasion on the landscape succession of Yancheng coastal natural wetlands, China link: https://peerj.com/articles/10400 last-modified: 2020-11-24 description: BackgroundThe Yancheng coastal natural wetlands (YCNR) are well-preserved silty tidal flat wetlands in China. Due to the severe invasion of Spartina alterniflora, the native ecosystem has undergone great changes. The successful invasion of S. alterniflora reduced the biodiversity of the YCNR, changed the structure and function of the local ecosystem, and eventually led to the degradation of the ecosystem and the loss of ecosystem function and service. Fully understanding the impact of an alien species invasion on YCNR succession is an important prerequisite for protecting and restoring the wetlands.MethodsIn this study, remote sensing, GIS technology, and a cellular-automaton Markov model were used to simulate the natural succession process of native ecosystems without being affected by alien species. By comparing the landscape of the YCNR with the model simulation results, we gained a better understanding of how alien species affect native landscape-scale ecosystems.ResultsDuring the natural succession of the coastal native wetland ecosystem in the YCNR, the pioneer species S. alterniflora occupied the mudflats and expanded seaward. The whole area expanded and moved seaward with an average annual movement of 58.23 m. Phragmites australis seemed to dominate the competition with S. salsa communities, and the area gradually expanded with an average annual movement of 39.89 m. The invasion of S. alterniflora changed the native ecosystem’s spatial succession process, causing the S. salsa ecosystem to be stressed by ecosystems on the side of the sea (S. alterniflora) and that of land (P. australis). The area of the seaward-expanding P. australis ecosystem has been declining. Under a reasonable protected area policy, human activities have enhanced the succession rate of the P. australis ecosystem and have had a small impact on the ecological spatial succession of S. salsa and S. alterniflora. creator: Lingjun Dai creator: Hongyu Liu creator: Gang Wang creator: Cheng Wang creator: Ziru Guo creator: Yi Zhou creator: Yufeng Li uri: https://doi.org/10.7717/peerj.10400 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Dai et al. title: The paleobiology and paleoecology of South African Lystrosaurus link: https://peerj.com/articles/10408 last-modified: 2020-11-24 description: Lystrosaurus was one of the few tetrapods to survive the end-Permian mass extinction (EPME), the most catastrophic biotic crisis in Phanerozoic history. The significant increased abundance of this genus during the post-extinction Early Triassic recovery period has made Lystrosaurus an iconic survivor taxon globally and ideal for studying changes in growth dynamics during a mass extinction. There is potential evidence of a Lilliput effect in Lystrosaurus in South Africa as the two Triassic species that became highly abundant after the EPME are relatively smaller than the two Permian species. In order to test this hypothesis a detailed examination of the body size and life history of Permo-Triassic Lystrosaurus is required. In this study, the basal skull length and growth patterns of the four South African Lystrosaurus species from the Karoo Basin, L. maccaigi, L. curvatus, L. murrayi and L. declivis, were examined using cranial measurements and bone histology. The basal skull length measurements show that the Triassic species are smaller than the Permian species and supports previous studies. The osteohistology examination of all four species reveal rapidly forming fibrolamellar bone tissues during early to mid-ontogeny. Growth marks are common in L. maccaigi and L. curvatus, but rare and inconsistent in the purely Triassic L. murrayi and L. declivis. The inconsistency of the growth marks in these latter two taxa suggests the presence of developmental plasticity. This feature may have been advantageous in allowing these species to alter their growth patterns in response to environmental cues in the post-extinction Early Triassic climate. An overall transition to slower forming parallel-fibered bone is observed in the largest individuals of L. maccaigi, but absent from the limb bones of the other species. The absence of such bone tissue or outer circumferential lamellae in L. curvatus, L. murrayi and L. declivis indicates that even the largest collected specimens do not represent fully grown individuals. Although L. murrayi and L. declivis are smaller in size, the lack of a growth asymptote in the largest specimens indicates that adult individuals would have been notably larger and may have been similar in size to large L. maccaigi and L. curvatus when fully grown. Thus, the previously described Lilliput effect, recognized by some authors in the Karoo fossil record (such as the therocephalian Moschorhinus kitchingi), may be a product of high juvenile excess mortality in the Triassic rather than a strict “dwarfing” of Lystrosaurus species. The lifestyle of Lystrosaurus was also re-examined. Although previous studies have proposed an aquatic lifestyle for the genus, the similar morphology and bone microanatomy to several other large terrestrial Permo-Triassic dicynodonts supports a fully terrestrial mode of life. creator: Jennifer Botha uri: https://doi.org/10.7717/peerj.10408 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Botha title: Classification of ovarian cancer associated with BRCA1 mutations, immune checkpoints, and tumor microenvironment based on immunogenomic profiling link: https://peerj.com/articles/10414 last-modified: 2020-11-24 description: BackgroundOvarian cancer is a highly fatal gynecological malignancy and new, more effective treatments are needed. Immunotherapy is gaining attention from researchers worldwide, although it has not proven to be consistently effective in the treatment of ovarian cancer. We studied the immune landscape of ovarian cancer patients to improve the efficacy of immunotherapy as a treatment option.MethodsWe obtained expression profiles, somatic mutation data, and clinical information from The Cancer Genome Atlas. Ovarian cancer was classified based on 29 immune-associated gene sets, which represented different immune cell types, functions, and pathways. Single-sample gene set enrichment (ssGSEA) was used to quantify the activity or enrichment levels of the gene sets in ovarian cancer, and the unsupervised machine learning method was used sort the classifications. Our classifications were validated using Gene Expression Omnibus datasets.ResultsWe divided ovarian cancer into three subtypes according to the ssGSEA score: subtype 1 (low immunity), subtype 2 (median immunity), and subtype 3 (high immunity). Most tumor-infiltrating immune cells and immune checkpoint molecules were upgraded in subtype 3 compared with those in the other subtypes. The tumor mutation burden (TMB) was not significantly different among the three subtypes. However, patients with BRCA1 mutations were consistently detected in subtype 3. Furthermore, most immune signature pathways were hyperactivated in subtype 3, including T and B cell receptor signaling pathways, PD-L1 expression and PD-1 checkpoint pathway the NF-κB signaling pathway, Th17 cell differentiation and interleukin-17 signaling pathways, and the TNF signaling pathway.ConclusionOvarian cancer subtypes that are based on immune biosignatures may contribute to the development of novel therapeutic treatment strategies for ovarian cancer. creator: Yousheng Wei creator: Tingyu Ou creator: Yan Lu creator: Guangteng Wu creator: Ying Long creator: Xinbin Pan creator: Desheng Yao uri: https://doi.org/10.7717/peerj.10414 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Wei et al. title: The pandemic paradox: domestic violence and happiness of women link: https://peerj.com/articles/10472 last-modified: 2020-11-24 description: BackgroundAcross the globe, lockdowns have been enforced as a pandemic response to COVID-19. Such lockdown coupled with school closures and stay-at-home orders made women more vulnerable in terms of higher responsibility and spending more time with an abusive partner, if any.MethodsThis study investigates the situation of women during COVID-19 induced lockdown by focusing on their happiness and inquiring about the incidence of violence. Using the zero-inflated negative binomial model, our findings ascertained that family settings, type of relationship with a spouse, and age significantly affects the positive count of violence during the lockdown. We further estimated the determinants of happiness and found that years of schooling, the role of women in household decision making, and feeling empowered is affecting their happiness.ResultsWomen having higher education have more odds of zero violence. Unemployed women and women who are not working have higher odds of zero violence as compared to women who are working. During this lockdown after the COVID-19 pandemic, women living in urban areas, having higher education, having an adequate household income to meet the expenditures, having lesser anxiety, not facing violence, feeling empowered when their husband is around, and have higher decision-making power are happier.Discussion and conclusionThe study is important in the context of happiness and violence inflicted on women during the lockdown and provides the basis to improve the pandemic response policy. The inclusion of women’s safety and happiness in pandemic response policy is important to ensure the well-being of women and to devise better health and economic policy. Our estimates suggest higher education results in less incidence of violence which could be argued as desirable outcomes for building healthy, productive, and happy communities. In addition to this, as pandemic induced lock-down is likely to result in higher unemployment across the globe including Pakistan, therefore, in light of our estimates pertaining to the role of unemployment in the incidence of violence, policymakers should deploy more resources to enhance income and to combat the rising unemployment. As a counter-intuitive outcome of these policy interventions, incidence of violence will be dampened, educational attainment and women empowerment will be increased which will certainly increase happiness. creator: Wajiha Haq creator: Syed Hassan Raza creator: Tahir Mahmood uri: https://doi.org/10.7717/peerj.10472 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2020 Haq et al.