Susceptibility of flexible plastic foodstuffs packaging against Monomorium indicum (Hymenoptera: Formicidae) household ants
Ants belonging to the Monomorium indicum (Formicidae: Hymenoptera) species are ubiquitous insects that are commonly associated with household settings in Pakistan. Packaged foodstuffs are easily destroyed by household ants when packaging is made with materials that have a high susceptibility. This study evaluated the susceptibility of three common flexible plastic packaging materials namely: opaque polyethylene, transparent polyethylene and polypropylene, which were each tested at thicknesses of 0.02 mm for their susceptibility against M. indicum. Except opaque polyethylene which is only available at 0.02 mm thickness, both transparent polyethylene and polypropylene were tested at higher thickness of 0.04 mm and 0.06 mm also against M. indicum. In order to simulate household settings, experiments were conducted at the faculty building of the agriculture and environment department of The Islamia University of Bahawalpur, Pakistan during summer vacations when the building was quiet. Different corners were selected near water sources for maximum exposure to the largest number of ants. Experimental cages used for the experiment were built with wood and 2 mm iron gauze to allow only ants to enter the cages. Daily activity of ants was used as an infestation source in cages. Experiments were run over three time spans of fifteen days each from June 20th 2022 to August 15th 2022. Results showed all packaging materials were susceptible against M. indicum at the 0.02 mm thickness level. Polypropylene was susceptible at 0.04 mm thickness but resistant to ants at 0.06 mm thickness, whereas polyethylene was still susceptible to ants at the higher thickness of 0.06 mm. Correlation of packaging damage with weather factors showed that temperature had a positive relationship, while relative humidity had a negative association with M. indicum attack. Overall correlation of packaging damage with packaging thickness showed packaging thickness was negatively associated with packaging damage from the ants. Because major cutting role is performed by the mandibles, we studied mandibles of ants and three frequent pests of packaged foodstuff namely Rhyzopertha dominica, Tribolium castaneum and Trogoderma granarium. The results showed that ants had the largest mandible and frontal mandibular tooth lengths compared with the mandibles and frontal teeth of the common stored product pests, indicating M. indicum household ants have a higher pest status for packaged foodstuffs compared to common stored product pests. Although the thickness of the flexible plastic packaging was a major factor against household ants, the study results recommend the use of polypropylene with a thickness of at least 0.06 mm as foodstuff packaging against household ants compared with polyethylene packaging, which was found to be susceptible to ants even at 0.06 mm thickness.
Environmental Contamination and Remediation
Iqbal et al. (2024) Susceptibility of flexible plastic foodstuffs packaging against Monomorium indicum (Hymenoptera: Formicidae) household ants. PeerJ 12:e16782 https://doi.org/10.7717/peerj.16782
Mowing wet meadows reduces the health of their snail communities
Wet meadows harbor rich biodiversity, making them pivotal ecosystems worldwide. These habitats are commonly used for grazing or hay production for livestock. However, regular mowing can influence these habitats, potentially leading to significant repercussions for the animals residing within them. In order to investigate the effects of land management practices, we conducted an experimental study to compare snail communities in mowed and unmowed wet meadows in northern Hungary. We found that overall, mowing decreases snail populations, as well as species richness and diversity. Thus, our results suggest that routine mowing of wet meadows is deleterious to their snail communities. Based on these results, we suggest that designated patches of meadows that are regularly managed should be left uncultivated in their natural state. These patches can serve as potential colonization sites, facilitating the restoration of the entire meadow’s ecological balance.
Farkas et al. (2024) Mowing wet meadows reduces the health of their snail communities. PeerJ 12:e16783 https://doi.org/10.7717/peerj.16783
Genome-wide identification and characterization of FAD family genes in barley
Fatty acid desaturases (FADs) play pivotal roles in determining plant stress tolerance. Barley is the most salt-tolerant cereal crop. In this study, we performed genome-wide identification and characterization analysis of the FAD gene family in barley (Hordeum vulgare). A total of 24 HvFADs were identified and divided into four subfamilies based on their amino acid sequence similarity. HvFADs unevenly distributed on six of seven barley chromosomes, and three clusters of HvFADs mainly occurred on the chromosome 2, 3 and 6. Segmental duplication events were found to be a main cause for the HvFAD gene family expansion. The same HvFAD subfamily showed the relatively consistent exon-intron composition and conserved motifs of HvFADs. Cis-element analysis in HvFAD promoters indicated that the expression of HvFADs may be subject to complex regulation, especially stress-responsive elements that may involve in saline-alkaline stress response. Combined transcriptomic data with quantitative experiments, at least five HvFADs highly expressed in roots under salt or alkali treatment, suggesting they may participate in saline or alkaline tolerance in barley. This study provides novel and valuable insights for underlying salt/alkali-tolerant mechanisms in barley.
Cao et al. (2024) Genome-wide identification and characterization of FAD family genes in barley. PeerJ 12:e16812 https://doi.org/10.7717/peerj.16812
Regulation of soldier caste differentiation by microRNAs in Formosan subterranean termite (Coptotermes formosanus Shiraki)
The soldier caste is one of the most distinguished castes inside the termite colony. The mechanism of soldier caste differentiation has mainly been studied at the transcriptional level, but the function of microRNAs (miRNAs) in soldier caste differentiation is seldom studied. In this study, the workers of Coptotermes formosanus Shiraki were treated with methoprene, a juvenile hormone analog which can induce workers to transform into soldiers. The miRNomes of the methoprene-treated workers and the controls were sequenced. Then, the differentially expressed miRNAs (DEmiRs) were corrected with the differentially expressed genes DEGs to construct the DEmiR-DEG regulatory network. Afterwards, the DEmiR-regulated DEGs were subjected to GO enrichment and KEGG enrichment analysis. A total of 1,324 miRNAs were identified, among which 116 miRNAs were screened as DEmiRs between the methoprene-treated group and the control group. A total of 4,433 DEmiR-DEG pairs were obtained. No GO term was recognized as significant in the cellular component, molecular function, or biological process categories. The KEGG enrichment analysis of the DEmiR-regulated DEGs showed that the ribosome biogenesis in eukaryotes and circadian rhythm-fly pathways were enriched. This study demonstrates that DEmiRs and DEGs form a complex network regulating soldier caste differentiation in termites.
Du et al. (2024) Regulation of soldier caste differentiation by microRNAs in Formosan subterranean termite (Coptotermes formosanus Shiraki). PeerJ 12:e16843 https://doi.org/10.7717/peerj.16843
Intensive pasture management alters the composition and structure of plant-pollinator interactions in Sibiu, Romania
Background Land management change towards intensive grazing has been shown to alter plant and pollinator communities and the structure of plant-pollinator interactions in different ways across the world. Land-use intensification in Eastern Europe is shifting highly diverse, traditionally managed hay meadows towards intensive pastures, but few studies have examined how this influences plant-pollinator networks. We hypothesized that the effects of intensive grazing on networks will depend on how plant communities and their floral traits change. Methods We investigated plant and pollinator diversity and composition and the structure of plant-pollinator interactions near Sibiu, Romania at sites that were traditionally managed as hay meadows or intensive pastures. We quantified the identity and abundance of flowering plants, and used transect walks to observe pollinator genera interacting with flowering plant species. We evaluated the effects of management on diversity, composition and several indices of network structure. Results Pollinator but not plant diversity declined in pastures and both plant and pollinator taxonomic composition shifted. Functional diversity and composition remained unchanged, with rather specialized flowers having been found to dominate in both hay meadows and pastures. Apis mellifera was found to be the most abundant pollinator. Its foraging preferences played a crucial role in shaping plant-pollinator network structure. Apis mellifera thus preferred the highly abundant Dorycnium herbaceum in hay meadows, leading to hay meadows networks with lower Shannon diversity and interaction evenness. In pastures, however, it preferred less abundant and more generalized flower resources. With pollinators being overall less abundant and more generalized in pastures, we found that niche overlap between plants was higher. Discussion With both hay meadows and pastures being dominated by plant species with similar floral traits, shifts in pollinator preferences seem to have driven the observed changes in plant-pollinator interaction networks. We thus conclude that the effects of grazing on pollinators and their interactions are likely to depend on the traits of plant species present in different management types as well as on the effects of grazing on plant community composition. We thereby highlight the need for better understanding how floral abundance shapes pollinator visitation rates and how floral traits may influence this relationship.
Neacă et al. (2024) Intensive pasture management alters the composition and structure of plant-pollinator interactions in Sibiu, Romania. PeerJ 12:e16900 https://doi.org/10.7717/peerj.16900
Changes in capture availability due to infection can lead to detectable biases in population-level infectious disease parameters
Correctly identifying the strength of selection that parasites impose on hosts is key to predicting epidemiological and evolutionary outcomes of host-parasite interactions. However, behavioral changes due to infection can alter the capture probability of infected hosts and thereby make selection difficult to estimate by standard sampling techniques. Mark-recapture approaches, which allow researchers to determine if some groups in a population are less likely to be captured than others, can be used to identify infection-driven capture biases. If a metric of interest directly compares infected and uninfected populations, calculated detection probabilities for both groups may be useful in identifying bias. Here, we use an individual-based simulation to test whether changes in capture rate due to infection can alter estimates of three key metrics: 1) reduction in the reproductive success of infected parents relative to uninfected parents, 2) the relative risk of infection for susceptible genotypes compared to resistant genotypes, and 3) changes in allele frequencies between generations. We explore the direction and underlying causes of the biases that emerge from these simulations. Finally, we argue that short series of mark-recapture sampling bouts, potentially implemented in under a week, can yield key data on detection bias due to infection while not adding a significantly higher burden to disease ecology studies.
Holmes et al. (2024) Changes in capture availability due to infection can lead to detectable biases in population-level infectious disease parameters. PeerJ 12:e16910 https://doi.org/10.7717/peerj.16910
Regional trends in the moderate-to-vigorous intensity physical activity and screen time of Canadians before and during the COVID-19 pandemic
Background During the COVID-19 pandemic, public health approaches and disease-transmission varied widely across Canadian regions. This may have led to different trajectories for moderate-to-vigorous intensity physical activity (MVPA) and screen time during this period. The purpose of this investigation was to describe age- and gender-specific regional trends in MVPA and screen time for Canadian youth (ages 12–17 years) and adults (ages 18+) from 2018 to 2021. Methods Data was collected using the Canadian Community Health Survey, which includes representative data for 5 distinct regions: Atlantic Canada, Québec, Ontario, the Prairie Provinces, and British Columbia (BC). Participants aged 12+ in each region self-reported their total daily screen time, as well as MVPA in 5 domains: overall, recreational, school, occupational/household and active transportation. Results were compared for 2018 (pre-pandemic), January–March of 2020, September–December of 2020, and 2021 using repeated measures t-tests. Results Among youth, all regions except for Atlantic Canada and BC experienced significant reductions in the proportion of youth meeting MVPA recommendations in the fall of 2020 (all p < 0.001), although these had returned to baseline for all regions except Ontario by 2021. Trends varied across regions among adults aged 18–64 years. In Québec, there was 7-percentage point reduction in the proportion of males meeting the MVPA recommendations in the fall of 2020 compared to 2018, while there was a 4-percentage point increase among females in 2021 (all p < 0.05). In Ontario and the Prairie provinces, males saw a 4-percentage point decrease in activity recommendation adherence in 2021, when compared to 2018 (p < 005). There were no other significant differences for any region when comparing the fall of 2020 or 2021 with 2018 (all p > 0.05). Among adults aged 65+ years, significant increases in MVPA were observed in Atlantic Canada and the Prairies in the fall of 2020, and in Atlantic Canada, Québec and the Prairies in 2021 (all p < 0.05). With limited exceptions, self-reported screen time increased significantly across regions and age groups for both males and females (all p < 0.05). Conclusions MVPA levels of Canadians during the COVID-19 pandemic varied both by region and age group. Self-reported MVPA of Canadian youth dropped in most regions in the fall of 2020, before returning to pre-pandemic levels in 2021. Activity levels of Canadians aged 18–64 years were relatively stable during the pandemic and increased for Canadians aged 65+ in most regions. Differences in trajectories across genders observed at the national level were often less apparent in individual regions. Recreational screen use increased across all regions, ages and genders with very few exceptions. These results highlight the differences and similarities in activity and screen time trajectories across the Canadian population and suggest the need for additional research to identify best practices for promoting healthy movement behaviours during future pandemics.
Saunders et al. (2024) Regional trends in the moderate-to-vigorous intensity physical activity and screen time of Canadians before and during the COVID-19 pandemic. PeerJ 12:e16913 https://doi.org/10.7717/peerj.16913
Molecular cloning and characterization of farnesyl diphosphate synthase from Rosa rugosa Thunb associated with salinity stress
Rosa rugosa, a renowned ornamental plant, is cultivated for its essential oil containing valuable monoterpenes, sesquiterpenes, and other compounds widely used in the floriculture industry. Farnesyl diphosphate synthase (FPPS) is a key enzyme involved in the biosynthesis of sesquiterpenes and triterpenes for abiotic or biotic stress. In this study, we successfully cloned and characterized a full-length FPPS- encoding cDNA identified as RrFPPS1 using RT-PCR from R. rugosa. Phylogenetic analysis showed that RrFPPS1 belonged to the angiosperm-FPPS clade. Transcriptomic and RT-qPCR analyses revealed that the RrFPPS1 gene had tissue-specific expression patterns. Subcellular localization analysis using Nicotiana benthamiana leaves showed that RrFPPS1 was a cytoplasmic protein. In vitro enzymatic assays combined with GC-MS analysis showed that RrFPPS1 produced farnesyl diphosphate (FPP) using isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP) as substrates to provide a precursor for sesquiterpene and triterpene biosynthesis in the plant. Additionally, our research found that RrFPPS1 was upregulated under salt treatment. These substantial findings contribute to an improved understanding of terpene biosynthesis in R. rugosa and open new opportunities for advancements in horticultural practices and fragrance industries by overexpression of the RrFPPS1 gene in vivo increased FPP production and subsequently led to elevated sesquiterpene yields in the future. The knowledge gained from this study can potentially lead to the development of enhanced varieties of R. rugosa with improved aroma, medicinal properties, and resilience to environmental stressors.
Wei et al. (2024) Molecular cloning and characterization of farnesyl diphosphate synthase from Rosa rugosa Thunb associated with salinity stress. PeerJ 12:e16929 https://doi.org/10.7717/peerj.16929
Research and experimental verification on the mechanisms of cellular senescence in triple-negative breast cancer
Background Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype with high heterogeneity, poor prognosis, and a low 10-year survival rate of less than 50%. Although cellular senescence displays extensive effects on cancer, the comprehensions of cellular senescence-related characteristics in TNBC patients remains obscure. Method Single-cell RNA sequencing (scRNA-seq) data were analyzed by Seurat package. Scores for cellular senescence-related pathways were computed by single-sample gene set enrichment analysis (ssGSEA). Subsequently, unsupervised consensus clustering was performed for molecular cluster identification. Immune scores of patients in The Cancer Genome Atlas (TCGA) dataset and associated immune cell scores were calculated using Estimation of STromal and Immune cells in MAlignantTumours using Expression data (ESTIMATE) and Microenvironment Cell Populations-counter (MCP-counter), Tumor Immune Estimation Resource (TIMER) and Estimating the Proportion of Immune and Cancer cells (EPIC) methods, respectively. Immunotherapy scores were assessed using TIDE. Furthermore, feature genes were identified by univariate Cox and Least Absolute Shrinkage and Selection Operator (LASSO) regression analyses; these were used to construct a risk model. Additionally, quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and transwell assay were conducted for in vitro validation of hub genes. Result TNBC was classified into three subtypes based on cellular senescence-related pathways as clusters 1, 2, and 3. Specifically, cluster 1 showed the best prognosis, followed by cluster 2 and cluster 3. The levels of gene expression in cluster 2 were the lowest, whereas these were the highest in cluster 3. Moreover, clusters 1 and 3 showed a high degree of immune infiltration. TIDE scores were higher for cluster 3, suggesting that immune escape was more likely in patients with the cluster 3 subtype who were less likely to benefit from immunotherapy. Next, the TNBC risk model was constructed and validated. RT-qPCR revealed that prognostic risk genes (MMP28, ACP5 and KRT6A) were up-regulated while protective genes (CT83) were down-regulated in TNBC cell lines, validating the results of the bioinformatics analysis. Meanwhile, cellular experiments revealed that ACP5 could promote the migration and invasion abilities in two TNBC cell lines. Finally, we evaluated the validity of prognostic models for assessing TME characteristics and TNBC chemotherapy response. Conclusion In conclusion, these findings help to assess the efficacy of targeted therapies in patients with different molecular subtypes, have practical applications for subtype-specific treatment of TNBC patients, and provide information on prognostic factors, as well as guidance for the revelation of the molecular mechanisms by which senescence-associated genes influence TNBC progression.
Cao et al. (2024) Research and experimental verification on the mechanisms of cellular senescence in triple-negative breast cancer. PeerJ 12:e16935 https://doi.org/10.7717/peerj.16935
The destructive subterranean termite Reticulitermes flavipes (Blattodea: Rhinotermitidae) can colonize arid territories
Reticulitermes flavipes, one of the most destructive subterranean termite species, has been detected for the first time in an arid territory: Lanzarote (Canary Islands, Spain). This invasive species was introduced into several countries but never such a dry region. Although there are places with presence of this termite at similar or even higher temperatures, none has annual rainfall (10.1 mm) as low as Lanzarote. On this island it is present in semi-desert, near an affected urban area. Distribution, genetic, climate and host-plant data are evaluated to track and understand its invasion process in the archipelago.
Hernández-Teixidor et al. (2024) The destructive subterranean termite Reticulitermes flavipes (Blattodea: Rhinotermitidae) can colonize arid territories. PeerJ 12:e16936 https://doi.org/10.7717/peerj.16936