High Level Of Variation Research Articles

Who prioritizes what? A cross‐jurisdictional comparative analysis of salmon fish passage strategies in Western Washington

AbstractConservation planners often rely on heuristic indices when challenged with prioritizing potential projects under a constrained budget. This paper presents a comparative analysis of several prioritization indices (PIs) of culvert fish passage barriers, which can contribute to declines in anadromous fish populations. A federal injunction requires Washington state to restore 90% of habitat blocked by state‐owned culverts by 2030, prompting the development of numerous PIs, by various entities (i.e., counties, cities) within the injunction area. Our comparative analysis of PIs within the injunction Case Area investigates their ability to distinguish between barriers, their transferability in terms of scoring metrics, how scoring weights differ, and the preferences implied thereby. We document the use of six distinct PI methods by 10 entities and find that some PIs used many shared metrics, whereas others used a high percentage of unique metrics that would be difficult to replicate outside the entity's jurisdiction. Although habitat potential, habitat quantity, and connectivity were considered across all PIs, we found a high level of variation in terms of the metric weights. Our methods can be employed in other geographies or for other restoration PI planning efforts, and our results may facilitate the development and refinement of future PIs.

Suicide Screening, Risk Assessment, and Lethal Means Counseling During Zero Suicide Implementation.

The authors measured implementation of Zero Suicide (ZS) clinical practices that support identification of suicide risk and risk mitigation, including screening, risk assessment, and lethal means counseling, across mental health specialty and primary care settings. Six health care systems in California, Colorado, Michigan, Oregon, and Washington participated. The sample included members ages ≥13 years from 2010 to 2019 (N=7,820,524 patients). The proportions of patients with suicidal ideation screening, suicide risk assessment, and lethal means counseling were estimated. In 2019, patients were screened for suicidal ideation in 27.1% (range 5.0%-85.0%) of mental health visits and 2.5% (range 0.1%-35.0%) of primary care visits among a racially and ethnically diverse sample (44.9% White, 27.2% Hispanic, 13.4% Asian, and 7.7% Black). More patients screened positive for suicidal ideation in the mental health setting (10.2%) than in the primary care setting (3.8%). Of the patients screening positive for suicidal ideation in the mental health setting, 76.8% received a risk assessment, and 82.4% of those identified as being at high risk received lethal means counseling, compared with 43.2% and 82.4%, respectively, in primary care. Six health systems that implemented ZS showed a high level of variation in the proportions of patients receiving suicide screening and risk assessment and lethal means counseling. Two opportunities emerged for further study to increase frequency of these practices: expanding screening beyond patients with regular health care visits and implementing risk assessment with lethal means counseling in the primary care setting directly after a positive suicidal ideation screening.

Mid-Pliocene not analogous to high-CO2 climate when considering Northern Hemisphere winter variability

Abstract. In this study, we address the question of whether the mid-Pliocene climate can act as an analogue for a future warm climate with elevated CO2 concentrations, specifically regarding Northern Hemisphere winter variability. We use a set of sensitivity simulations with the global coupled climate model CESM1.0.5 (CCSM4-Utr), which is part of the PlioMIP2 model ensemble, to separate the response to a CO2 doubling and to mid-Pliocene boundary conditions other than CO2. In the CO2 doubling simulation, the Aleutian low deepens, and the Pacific–North American pattern (PNA) strengthens. In response to the mid-Pliocene boundary conditions, sea-level pressure variance decreases over the North Pacific, the PNA becomes weaker and the North Pacific Oscillation (NPO) becomes the dominant mode of variability. The mid-Pliocene simulation shows a weak North Pacific jet stream that is less variable in intensity but has a high level of variation in jet latitude, consistent with a dominant NPO and indicating that North Pacific atmospheric dynamics become more North Atlantic-like. We demonstrate that the weakening of the Aleutian low, and subsequent relative dominance of the NPO over the PNA, is related to shifts in tropical Pacific convection. Variability in the North Atlantic shows little variation between all simulations. The opposite response in North Pacific winter variability to elevated CO2 or mid-Pliocene boundary conditions demonstrates that the mid-Pliocene climate cannot serve as a future analogue in this regard.

A Social Network Analysis of a Multi-sector Service System for Intimate Partner Violence in a Large US City

About one in four women in the US report having experienced some form of intimate partner violence (IPV) during their lifetime and an estimated 15.5 million children live in families in which IPV occurred in the past year. Families of young children with IPV experiences often face complex needs and require well-coordinated efforts among service providers across social and health sectors. One promising partnership aims to support pregnant and parenting IPV survivors through coordination between IPV agencies and community-based maternal and early childhood home visiting programs. This study used social network analysis (SNA) to understand the interconnectedness of the system of IPV prevention and intervention for families with young children in a large US city. The SNA included 43 agencies serving this population across various service domains spanning IPV, legal, maternal and child health, and public benefit programs. An SNA survey collected data on four forms of collaboration between agencies, including formal administrative relationship, referral reciprocity, case consultation, and shared activities in community committees/organizing bodies. Density and centrality were the primary outcomes of interest. A community detection analysis was performed as a secondary analysis. The overall level of interconnectedness between the 43 responding agencies was low. Making referrals to each other was the most common form of collaboration, with a network density of 30%. IPV agencies had the highest average number of connections in the networks. There was a high level of variation in external collaborations among home visiting agencies, with several home visiting agencies having very few connections in the community but one home visiting program endorsing collaborative relationships with upwards of 38 partner agencies in the network. In serving families at risk for IPV, home visiting agencies were most likely to have referral relationships with mental health provider agencies and substance use disorder service agencies. A community detection analysis identified distinct communities within the network and demonstrated that certain agency types were more connected to one another while others were typically siloed within the network. Notably, the IPV and home visiting communities infrequently overlapped. Sensitivity analyses showed that survey participants’ knowledge of their agencies’ external collaborations varied by their work roles and agencies overall had low levels of consensus about their connectedness to one another. We identified a heterogeneous service system available to families of young children at-risk for or experiencing IPV. Overall inter-agency connectedness was low, with many siloed agencies and a lack of shared knowledge of community resources. Understanding current collaborations, silos, and centrality of agencies is an effective public health tool for allocating scarce resources across diverse service sectors to efficiently improve the system serving families experiencing IPV.

Evaluating Decadal Changes in Determinants of Early Childhood Stunting and Assessing Their Contribution to Socio-economic Disparity in Child Nutritional Status Across India

Various efforts have been made over the years to bring about reduction in child malnutrition; the latest among them involves Goal 2 of the SDGs. The SDG Target 2.2 recognizes the global dimension of the nutrition issue and aims to end all forms of malnutrition by 2030, including achieving, by 2025, (WHO, 2015). The present evidence on childhood malnutrition suggests that while improvement in maternal and child covariates have resulted in decline of childhood stunting over time. The present study aims to investigate how the effect of maternal and child covariates on early childhood malnutrition have changed over the last decade and examining the socio-economic disparity in the nutritional status of children across India. The present study utilizes data from the last two rounds of the National Family Health Survey, NFHS-3 in 2005-06 and NFHS-4 in 2015-16 of children in the age group 6-23 months for whom data on height-for-age was available from the last two rounds of the National Family Health Survey (NFHS-3 and NFHS-4). After dropping the missing and flagged cases, the total sample size was 12,507 and 68,246 children from NFHS-3 (2005-06) and NFHS-4 (2015-16), respectively. The selected indicator of childhood under nutrition for this study is stunting. The exposure variables selected for the study were child factors such as sex, age, birth order, size at birth, place of delivery, diet diversity, meal frequency and early initiation of breastfeeding. Maternal factors such as maternal education, media exposure, and mother’s BMI were taken into account. For healthcare service utilization we considered the variable of complete antenatal care. Other background characteristics like religion, caste, wealth index, place of residence and geographical region were also considered. We utilized chi-square test to test for the association of various factors with early childhood stunting followed by t-test to assess the changes in prevalence by each factor. We also carried out bivariate and multivariate logistic analysis to effect of various factors on childhood stunting. Lastly, we carried out Oaxaca decomposition to examine the contribution of the determinants of childhood stunting towards the changes in its prevalence over the last ten years. Concentration Index was calculated to examine the disparity in early childhood stunting across India for both rounds of the National Family Health Survey. The predictive probabilities were calculated for each category of the wealth index after fitting a logistic model to control for other determinants of early childhood stunting to assess the change in prevalence of stunting across each socio-economic group in the last ten years. The study reveals an overall decline in prevalence of early childhood stunting across India over the last ten years from 2005-16. However, high levels of variation continue to exist across all the states in India. The study reveals institutional delivery as the highest contributing factor for this decline. Maternal education, body mass index and complete antenatal care during pregnancy also contribute significantly to the improvement in childhood stunting

MARTin-an open-source platform for microarray analysis.

Background: Microarray technology has brought significant advancements to high-throughput analysis, particularly in the comprehensive study of biomolecular interactions involving proteins, peptides, and antibodies, as well as in the fields of gene expression and genotyping. With the ever-increasing volume and intricacy of microarray data, an accurate, reliable and reproducible analysis is essential. Furthermore, there is a high level of variation in the format of microarrays. This not only holds true between different sample types but is also due to differences in the hardware used during the production of the arrays, as well as the personal preferences of the individual users. Therefore, there is a need for transparent, broadly applicable and user-friendly image quantification techniques to extract meaningful information from these complex datasets, while also addressing the challenges posed by specific microarray and imager formats, which can flaw analysis and interpretation. Results: Here we introduce MicroArray Rastering Tool (MARTin), as a versatile tool developed primarily for the analysis of protein and peptide microarrays. Our software provides state-of-the-art methodologies, offering researchers a comprehensive tool for microarray image quantification. MARTin is independent of the microarray platform used and supports various configurations including high-density formats and printed arrays with significant x and y offsets. This is made possible by granting the user the ability to freely customize parts of the application to their specific microarray format. Thanks to built-in features like adaptive filtering and autofit, measurements can be done very efficiently and are highly reproducible. Furthermore, our tool integrates metadata management and integrity check features, providing a straightforward quality control method, along with a ready-to-use interface for in-depth data analysis. This not only promotes good scientific practice in the field of microarray analysis but also enhances the ability to explore and examine the generated data. Conclusion: MARTin has been developed to empower its users with a reliable, efficient, and intuitive tool for peptidomic and proteomic array analysis, thereby facilitating data-driven discovery across disciplines. Our software is an open-source project freely available via the GNU Affero General Public License licence on GitHub.

Host Genetic Variation Impacts SARS-CoV-2 Vaccination Response in the Diversity Outbred Mouse Population.

The COVID-19 pandemic led to the rapid and worldwide development of highly effective vaccines against SARS-CoV-2. However, there is significant individual-to-individual variation in vaccine efficacy due to factors including viral variants, host age, immune status, environmental and host genetic factors. Understanding those determinants driving this variation may inform the development of more broadly protective vaccine strategies. While host genetic factors are known to impact vaccine efficacy for respiratory pathogens such as influenza and tuberculosis, the impact of host genetic variation on vaccine efficacy against COVID-19 is not well understood. To model the impact of host genetic variation on SARS-CoV-2 vaccine efficacy, while controlling for the impact of non-genetic factors, we used the Diversity Outbred (DO) mouse model. We found that DO mice immunized against SARS-CoV-2 exhibited high levels of variation in vaccine-induced neutralizing antibody responses. While the majority of the vaccinated mice were protected from virus-induced disease, similar to human populations, we observed vaccine breakthrough in a subset of mice. Importantly, we found that this variation in neutralizing antibody, virus-induced disease, and viral titer is heritable, indicating that the DO serves as a useful model system for studying the contribution of genetic variation of both vaccines and disease outcomes.

Environmental heterogeneity modifies the link between personality and survival in fluctuating small mammal populations.

Despite numerous studies examining the fitness consequences of animal personalities, predictions concerning the relationship between personality and survival are not consistent with empirical observations. Theory predicts that individuals who are risky (i.e. bold, active and aggressive) should have higher rates of mortality; however, empirical evidence shows high levels of variation in behaviour-survival relationships in wild populations. We suggest that this mismatch between predictions under theory and empirical observations results from environmental contingencies that drive heterogeneity in selection. This uncertainty may constrain any universal directional relationships between personality traits and survival. Specifically, we hypothesize that spatiotemporal fluctuations in perceived risk that arise from variability in refuge abundance and competitor density alter the relationship between personality traits and survival. In a large-scale manipulative experiment, we trapped four small mammal species in five subsequent years across six forest stands treated with different management practices in Maine, United States. Stands all occur within the same experimental forest but contain varying amounts of refuge and small mammal densities fluctuate over time and space. We quantified the effects of habitat structure and competitor density on the relationship between personality traits and survival to assess whether directional relationships differed depending on environmental contingencies. In the two most abundant species, deer mice and southern red-backed voles, risky behaviours (i.e. higher aggression and boldness) predicted apparent monthly survival probability. Mice that were more aggressive (less docile) had higher survival. Voles that were bolder (less timid) had higher survival, but in the risky forest stands only. Additionally, traits associated with stress coping and de-arousal increased survival probability in both species at high small mammal density but decreased survival at low density. In the two less abundant study species, there was no evidence for an effect of personality traits on survival. Our field experiment provides partial support for our hypothesis: that spatiotemporal fluctuations in refuge abundance and competitor density alter the relationship between personality traits and survival. Our findings also suggest that behaviours associated with stress coping and de-arousal may be subject to density-dependent selection and should be further assessed and incorporated into theory.

Comparative chloroplast genome analyses provide new insights into phylogeny of Taraxacum and molecular markers for distinguishing rubber producing dandelions from their weedy relatives in China

Taraxacum species are utilized as traditional herbal medicine or as industrial crops to producing natural rubber. However, the classification of Taraxacum species has long been a challenge, thereby limiting their industrial application. To facilitate the correct screening rubber-producing dandelions from the weedy relatives, 38 chloroplast (Cp) genomes of Taraxacum spp. mainly gathered in Xinjiang, China, were assembled, including both rubber- and non-rubber-producing ones, and were used to reconstruct the phylogeny of Taraxacum. The results reveal that T. mongolicum and T. dealbatum are the primitive species in Taraxacum studied here, while T. erythrospermum and T. compactum are the closest relatives to the rubber-producing dandelion T. kok-saghyz. The discrepancies among the phylogenetic relationships inferred from Cp genomes, nuclear ribosomal internal transcribed spacer and morphology traits reflect chloroplast capture events due to putative ancient cross-species hybridization within Taraxacum. Comparative genomic analysis showed that, although highly conserved for most areas, some regions exhibit relatively high levels of variation in Cp genomes among different Taraxacum species, such as ndhD-ccsA and trnL-trnF regions. A total of 37 loci in Taraxacum Cp genomes were identified as novel putative molecular markers that might assist to distinguish rubber producing dandelions from their weedy relatives in their distribution center. Our results provide new insights into the phylogenetic relationships within the genus Taraxacum. In addition, the Cp genomic resources reported in this study provide genetic foundation for distinguishing rubber producing dandelions from their weedy relatives and future exploration of these industrial important species.

Comparison of Forecasting Accuracy Using the Short Moving Average (SMA) Method Using Boxplot Outlier Filtering and Not Using Outlier Filtering for Data that has a high level of variation

The Short Moving Average (SMA) forecasting method is one of the most widely used forecasting methods, especially for processing data with a high level of variation and is not linear with time. However, opportunities to develop and improve forecasting performance using the SMA method are still wide open. The performance of a forecasting method can be seen from the distribution of errors. SMA does not see and does not sort the type of input data that will be processed into a forecast value, whether the input data has small or large variations, or has outlier data. If the input data has an outlier, then that outlier can make the forecasting performance not good. One of the efforts to improve SMA forecasting performance is by filtering outlier data. In this study, a comparison was made of the forecasting results for SMA using outlier filtering with the forecasting results for SMA not using outlier filtering. The next step is to compare the error values, namely those that produce the smallest Mean Squared Error (MSE) and Mean Absolute Percentage Error (MAPE) values. From the results of the study it can be seen that the performance of SMA using the Boxplot filtering method gives better forecasting results than those without using outlier filtering.

Plantago lanceolata L. Taksonunda Tohum Kabuk Varyasyonu ve Bunun Yaygın Bitki Taksonlarında Tohum Yüzey Karakterlerinin Kullanımına Etkileri

Seed coat micromorphology has been great help in systematic studies over the past century. It is useful in most plant groups, including the widespread taxa. Although phenotypic plasticity in plants is a well-known phenomenon, there are not many micromorphological studies investigating whether plants with wide distribution areas show variation in seed coat characteristics. Plantago lanceolata L. (Plantaginaceae), as one of the most widespread Plantago taxa, is used in this study to investigate the presence of seed microsculpture variation among different populations. The seeds of 50 populations from across Turkey were analyzed using Stereomicroscope and SEM. Some seed surface characters of P. lanceolata were found to be consistent (cell shapes and anticlinal wall shapes), whereas others were variable (anticlinal walls, periclinal walls and surface sculpture). Irregularly wrinkled surface is reported in P. lanceolata seeds for the first time in this study. No correlation between geographical differences and seed characters were found. These results indicate that caution should be taken when dealing with widespread taxa with high levels of variation.

Spatial Variation in Yield, Chemical Composition, and Phytotoxic Activity of Cistus ladanifer Essential Oils.

Cistus ladanifer L. (rockrose) is a widespread shrub species of the Mediterranean region with products highly valued by the perfume and cosmetics industry. In this research, the variability in yield, chemical composition and phytotoxic activity of C. ladanifer essential oils collected from 12 plots belonging to four natural populations and settled on two different types of edaphic substrates were evaluated. The essential oils were analyzed by GC-MS. The essential oil content ranged from 0.19 to 0.42 mL/100 g. The volatile profiles were found to be rich in oxygenated sesquiterpenes and oxygenated monoterpenes. PCA analysis clustered the samples into two groups that were mainly attributed to the type of substrate on which the plants grow. Furthermore, CCA and correlation analysis revealed that soil organic matter was the most effective edaphoclimatic driver accounting for these high levels of variation in essential oil yield and composition. Finally, C. ladanifer essential oils showed strong phytotoxic activity on R. sativus seedlings, indicating its potential use as a natural bio-herbicide in agriculture. The results showed that the effect associated to local edaphoclimatic conditions not only impacted on the quality and quantity of the essential oil, but also on the industrial uses derived from its biological activities.

FRI291 Musashi1 And Musashi2 Mark Distinct Pituitary Stem Cell Populations

Abstract Disclosure: Y. Rahmatallah: None. J. Banik: None. K. Bronson: None. M.C. MacNicol: None. The cell plastic state of the pituitary is required to meet the changing demands upon pituitary function and may also result in these cells being more vulnerable to malignant transformation. The mechanisms that control pituitary cell plasticity are unknown. The RNA binding protein Musashi (MSI) is expressed in embryonic stem cells, and in cancer stem cells, where MSI functions to promote stem cell plasticity and to oppose premature cell maturation. MSI is also expressed at high levels in adult gonad and adult pituitary. The function of MSI in adult tissues is not fully understood, and the mechanisms that control the pro-proliferative and pro-malignant aspects of MSI function in adult tissues are not known. The two evolutionarily conserved MSI proteins, Musashi1 (MSI1) and Musashi2 (MSI2), are predicted to function redundantly, however, regulatory distinctions have been reported for MSI1 and MSI2. Towards a characterization of MSI1 and MSI2 in pituitary, we analyzed transcriptomics data from public datasets of single-nucleus and single-cell and bulk-tissue gene expression data from physiological and pathophysiological human pituitary tissue. We performed bioinformatics analysis utilizing the single-cell genomics analysis tool, Seurat in R and the pseudotime trajectory analysis tool Monocle and additional genomics and statistics analyses tools in R. We identify the MSI1-expressing pituitary cell population as immature stem cells and the distinct MSI2-expressing pituitary cell population as more mature, committed progenitor cells. Pituitary from human fetal tissue contains multiple distinct MSI1-expressing cell populations while, in contrast, pituitary from human adult tissue contains multiple distinct MSI2-expressing cell populations. Pituitary from human pediatric tissue demonstrates an intermediate state with both distinct MSI1-expressing and distinct MSI2-expressing cell populations. We identify increased MSI1 expression but not increased MSI2 expression in adult pituitary adenoma, and a high level of variation in the MSI1 to MSI2 expression ratio between distinct pituitary adenomas. Based upon this re-analysis of reposited datasets from other pituitary investigators, we hypothesize that the increase that we observe, in MSI1 to MSI2 expression ratio in adult pituitary tumors is consistent with a reversion of mature cells to an earlier immature state. Adult pituitary may contain the mechanisms that regulate MSI2 function but may not be equipped to properly control high levels of re-expressed MSI1. An understanding of the physiological functions and mechanisms of regulation of the distinct MSI proteins in pituitary may provide insight into potential mechanisms that could be recruited to increase physiological pituitary cell growth and differentiation in regenerative therapy and to oppose pathological cell growth in pituitary tumor. Presentation: Friday, June 16, 2023

Individual variation in vaccine immune response can produce bimodal distributions of protection

The ability for vaccines to protect against infectious diseases varies among individuals, but computational models employed to inform policy typically do not account for this variation. Here we examine this issue: we implement a model of vaccine efficacy developed in the context of SARS-CoV-2 in order to evaluate the general implications of modelling correlates of protection on the individual level. Due to high levels of variation in immune response, the distributions of individual-level protection emerging from this model tend to be highly dispersed, and are often bimodal. We describe the specification of the model, provide an intuitive parameterisation, and comment on its general robustness. We show that the model can be viewed as an intermediate between the typical approaches that consider the mode of vaccine action to be either “all-or-nothing” or “leaky”. Our view based on this analysis is that individual variation in correlates of protection is an important consideration that may be crucial to designing and implementing models for estimating population-level impacts of vaccination programs.

The Sphagnum cuspidatum complex: phylogeny, species delimitation, and morphology

Abstract The use of species as a concept is an important metric for assessing biological diversity and ecosystem function. However, delimiting species based on morphological characters can be difficult, especially in aquatic plants that exhibit high levels of variation and overlap. The Sphagnum cuspidatum complex, which includes plants that dominate peatland hollows, provides an example of challenges in species delimitation. Microscopic characters that have been used to define taxa and the possibility that these characters may simply be phenoplastic responses to variation in water availability make species delimitation in this group especially difficult. In particular, the use of leaf shape and serration, which have been used to separate species in the complex, have resulted in divergent taxonomic treatments. Using a combination of high-resolution population genomic data (RADseq) and a robust morphological assessment of plants representing the focal species, we provide evidence to evaluate putative species in this complex. Our data support the recognition of S. cuspidatum, S. fitzgeraldii, S. mississippiense, and S. trinitense as genetically distinct species that can be separated morphologically. These results indicate that S. viride does not differ genetically from S. cuspidatum. Our results are broadly relevant to other aquatic groups where leaf shape and marginal teeth are used to distinguish species.

Identification, proteolytic activity quantification and biofilm-forming characterization of Gram-positive, proteolytic, psychrotrophic bacteria isolated from cold raw milk.

Psychrotrophic bacteria of raw milk face the dairy industry with significant spoilage and technological problems due to their ability to produce heat-resistant enzymes and biofilms. Despite extensive information about Gram-negative psychrotrophic bacteria in milk, little is known about Gram-positive psychrotrophic bacteria in milk, and their proteolytic activity and biofilm-forming characteristics. In the present study, Gram-positive, proteolytic, psychrotrophic bacteria of cold raw milk were identified, and their proteolytic activity and biofilm-forming capacity were quantified. In total, 12 genera and 22 species were represented among the bacterial isolates, however 50% belonged to three genera, namely Staphylococcus (19.4%), Bacillus (16.7%), and Enterococcus (13.9%). Different levels of proteolytic activity were detected in the identified isolates, even among the strains belonging to the same species. In addition, proteolytic activity was significantly higher at 25°C than at 7°C for all isolates. The crystal violet staining assay in polystyrene microtitre plates revealed a high level of variation in the biofilm-forming capacity at 7°C. After 72 hours of incubation, 11.1% of the strains did not produce a biofilm, while 27.8%, 52.8%, and 8.3% produced low, moderate, and high amounts of biofilm on polystyrene, respectively. The psychrotrophic bacteria were also able to produce biofilms on the surface of stainless steel coupons in ultra-high temperature milk after 72 h of incubation at 7°C; the number of attached cells ranged from 1.34 to 5.11 log cfu/cm2. These results expand the knowledge related to the proteolytic activity and biofilm-forming capacity of Gram-positive psychrotrophic milk bacteria.

Microfluidic single-cell measurements of oxidative stress as a function of cell cycle position.

Single-cell measurements routinely demonstrate high levels of variation between cells, but fewer studies provide insight into the analytical and biological sources of this variation. This is particularly true of chemical cytometry, in which individual cells are lysed and their contents separated, compared to more established single-cell measurements of the genome and transcriptome. To characterize population-level variation and its sources, we analyzed oxidative stress levels in 1278 individual Dictyostelium discoideum cells as a function of exogenous stress level and cell cycle position. Cells were exposed to varying levels of oxidative stress via singlet oxygen generation using the photosensitizer Rose Bengal. Single-cell data reproduced the dose-response observed in ensemble measurements by CE-LIF, superimposed with high levels of heterogeneity. Through experiments and data analysis, we explored possible biological sources of this heterogeneity. No trend was observed between population variation and oxidative stress level, but cell cycle position was a major contributor to heterogeneity in oxidative stress. Cells synchronized to the same stage of cell division were less heterogeneous than unsynchronized cells (RSD of 37-51% vs 93%), and mitotic cells had higher levels of reactive oxygen species than interphase cells. While past research has proposed changes in cell size during the cell cycle as a source of biological noise, the measurements presented here use an internal standard to normalize for effects of cell volume, suggesting a more complex contribution of cell cycle to heterogeneity of oxidative stress.

Characterization of Tomato Genotypes for Important Fruit Quality Traits

Characterization of Tomato Genotypes for Important Fruit Quality Traits

Behavioral diversity and biomechanical determinants of the outcome of a fish predator–prey interaction

AbstractPredator–prey interactions are ubiquitous and under strong selection because of the consequences experienced by both predator and prey if they lose the interaction. Biomechanics and behavior play important roles in the outcome of these interactions, but many studies focus on the prey, restrict the range of behaviors considered, and the role of prey boldness in the outcome is not understood. We used high‐speed video to test for effects of multiple measures of performance and kinematics of both the predator and prey, and boldness of prey on the outcome of interactions between Pike Cichlids (Crenicichla sp.) and Guppies (Poecilia reticulata). We found high variation in the behaviors employed during the predator–prey interactions, including in suction versus raptorial feeding, strike accuracy, and guppy responsiveness. We also found that predators moving relatively slower and prey moving relatively faster were more successful at consuming the prey and evading the predator, respectively. Prey that reacted farther from the predator was more likely to escape predation, but boldness of the prey did not affect the interaction. Our work suggests that a high level of variation in predator–prey interactions is widespread, even when strike and escape behaviors are stereotyped. We also showed that what both the predator and the prey do during an interaction are important in determining the outcome.

Gut microbiology of UK care home residents: a cross-sectional analysis from a randomised controlled trial

ObjectiveTo describe the prevalence of potentially clinically relevant gut pathogens and associations with the carriage of resistant organisms in UK care home residents. MethodsStool samples were collected pre-randomisation from care home residents participating in a randomised placebo-controlled trial. Cultivable clinically relevant bacteria were analysed. Antimicrobial susceptibility testing was performed by agar dilution (amoxicillin, co-amoxiclav, gentamicin, trimethoprim, nitrofurantoin, and ciprofloxacin). We also aimed to detect resistance to third-generation cephalosporins, carbapenems, and vancomycin. ResultsStool samples were available for 159/310 residents participating in the trial (51%) from 23 care homes between 2016 and 2018. In total, 402 bacterial isolates were cultured from 158 stool samples and 29 different species were cultured. The five most common species were Escherichia coli (155/158, 98%), Pseudomonas aeruginosa (40/158, 25%), Enterococcus faecalis (35/158, 22%), Enterococcus faecium (30/158, 19%), and Proteus mirabilis (25/158, 16%). Enterobacterales isolates were cultured from 157 samples (99%), and resistance to at least one of the tested antimicrobials was found in 119 of these (76%). There were high levels of variation in outcomes by care home. DiscussionWe demonstrated that care home residents harbour significant levels of antimicrobial-resistant organisms in their stool. This work emphasises the importance of both enhanced infection control practices and antimicrobial stewardship programmes to support the appropriate use of antimicrobials in this setting.