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Motivated primarily by the large uncertainties in the thermonuclear rate of the 30P(p,γ)31S reaction that limit our understanding of classical novae, we carried out lifetime measurements of 31S excited states using the Doppler Shift Lifetimes (DSL2) facility at the TRIUMF Isotope Separator and Accelerator (ISAC-II) facility. The 31S excited states were populated by the 3He(32S,α)31S reaction. The deexcitation γ rays were detected by a clover-type high-purity germanium detector in coincidence with the α particles detected by a silicon detector telescope. We have applied modern Markov chain Monte Carlo-based Bayesian statistical techniques to perform lineshape analyses of Doppler-shift attenuation method γ-ray data for the first time. We have determined the lifetimes of the two lowest-lying 31S excited states. First experimental upper limits on the lifetimes of four higher-lying states have been obtained. The experimental results were compared to shell-model calculations using five universal sd-shell Hamiltonians. Evidence for γ rays originating from the astrophysically important Jπ=3/2+, 260-keV 30P(p,γ)31S resonance with an excitation energy of Ex=6390.2(7) keV in 31S has also been observed, although strong constraints on the lifetime will require better statistics.

Data-based decision-making (DBDM) using curriculum-based measurement (CBM) data has demonstrated effectiveness in improving academic achievement for students with or at risk for learning disability. Despite substantial evidence supporting DBDM, its use is not common practice for many educators, even those who regularly collect CBM data. One explanation for its lack of widespread use is that educators may not receive adequate training in the DBDM aspects of CBM. Espin et al. examined the extent to which DBDM is represented in CBM professional development (PD) materials and found that the topic was significantly underrepresented (12% to 14% of CBM PD material content) compared with other CBM topics. The purpose of this study was to conduct a conceptual replication of the Espin et al. systematic review through an analysis of CBM content in practitioner journal articles. The present review includes 29 practitioner articles coded to the four CBM categories used in the Espin et al. study: (a) general CBM information, (b) conducting CBM, (c) data-based decision-making, and (d) other. Results revealed a pattern similar to the one found by Espin et al. with approximately 18% of the content of practitioner articles on CBM devoted to the topic of decision-making. These findings strengthen the recommendation from Espin et al. for increased attention to DBDM in CBM training materials.

Certain astrophysical environments such as thermonuclear outbursts on accreting neutron stars (Type-I X-ray bursts) are hot enough to allow for breakout from the Hot CNO hydrogen burning cycles to the rapid proton capture (rp) process. An important breakout reaction sequence is 15O(α,γ)19Ne(p,γ)20Na and the 19Ne(p,γ)20Na reaction rate is expected to be dominated by a single resonance at 457 keV above the proton threshold in 20Na. The resonance strength and, hence, reaction rate depends strongly on whether this 20Na state at an excitation energy of 2647 keV has spin and parity of 1+ or 3+. Previous 20Mg (Jπ=0+) β+ decay experiments have relied almost entirely on searches for β-delayed proton emission from this resonance in 20Na to limit the log ft value and, hence, Jπ. However there is a non-negligible γ-ray branch expected that must also be limited experimentally to determine the log ft value and constrain Jπ. We have measured the β-delayed γ decay of 20Mg to complement previous β-delayed proton decay work and provide the first complete limit based on all energetically allowed decay channels through the 2647 keV state. Our limit confirms that a 1+ assignment for this state is highly unlikely.

PurposeThe purpose of this study was to analyze changes in skeletal muscle oxygen saturation (SmO2) kinetics during exercise in female rowers both acutely and longitudinally in relation to blood lactate (BLa). We also aimed to determine the agreement and statistical equivalence between physiological thresholds derived from SmO2 and BLa kinetics.MethodsTwenty-three female NCAA Division I rowers were tested throughout the 2023–2024 academic year. Of these, 11 athletes completed at least two near-infrared spectroscopy (NIRS)-equipped GXTs, with physiological data analyzed for longitudinal changes. A 7x4-min discontinuous GXT protocol was performed by all athletes. First and second SmO2 breakpoints (SmO2BP1 and SmO2BP2) were estimated via piecewise linear regression modeling, and BLa thresholds (LT1 and LT2) were calculated using ADAPT software. Paired-samples t-tests assessed differences, and equivalence was tested using two one-sided tests (TOST). Agreement was determined using Bland-Altman analysis yielding mean differences (MD) and 95% limits of agreement (LoA). Intraclass correlation coefficients (ICC2,1) were also calculated.ResultsNo difference was found between SmO2BP2 and LT2 (MD = −5.76W [95% LoA = −38.52 to 22.25W], p = 0.134), moderate-to-good levels of agreement (ICC2,1 = 0.67 [95% CI: 0.36–0.85], p < 0.001), and no statistical equivalence (p = 0.117). This was not the case for SmO2BP1 and LT1, with NIRS significantly underestimating LT1 (MD = −8.14W [95% LoA = −38.90 to 27.37W], p = 0.026), poor-to-moderate agreement (ICC2,1 = 0.24 [95% CI: −0.13–0.58], p = 0.10), and no statistical equivalence (p = 0.487). Additionally, SmO2 recovery kinetics (SmO2resat) during 1-min rest intervals increased in response to graded increases in exercise intensity (p < 0.001, η2p = 0.71), with higher intensities appearing to blunt this effect (step 6 – step 7: MD = −0.16%⋅s-1, p = 0.69). No statistically significant changes were observed in LT’s or SmO2BP’s throughout the 2023–2024 season.ConclusionIn female collegiate rowers, NIRS may be a tool that compliments BLa testing when determining the second lactate threshold (i.e., LT2). However, significant inter-individual variablility exists between SmO2BP2 and LT2 paired with a lack of statistical equivalence suggest the two are not interchangeable. While not a standalone replacement, if used in combination with traditional BLa testing methods NIRS may be a complimentary tool that helps inform individual athlete training zone prescription.

IntroductionData science training has the potential to propel environmental health research efforts into territories that remain untapped and holds immense promise to change our understanding of human health and the environment. Though data science training resources are expanding, they are still limited in terms of public accessibility, user friendliness, breadth of content, tangibility through real-world examples, and applicability to the field of environmental health science.MethodsTo fill this gap, we developed an environmental health data science training resource, the inTelligence And Machine lEarning (TAME) Toolkit, version 2.0 (TAME 2.0).ResultsTAME 2.0 is a publicly available website that includes training modules organized into seven chapters. Training topics were prioritized based upon ongoing engagement with trainees, professional colleague feedback, and emerging topics in the field of environmental health research (e.g., artificial intelligence and machine learning). TAME 2.0 is a significant expansion upon the original TAME training resource pilot. TAME 2.0 specifically includes training organized into the following chapters: (1) Data management to enable scientific collaborations; (2) Coding in R; (3) Basics of data analysis and visualizations; (4) Converting wet lab data into dry lab analyses; (5) Machine learning; (6) Applications in toxicology and exposure science; and (7) Environmental health database mining. Also new to TAME 2.0 are “Test Your Knowledge” activities at the end of each training module, in which participants are asked additional module-specific questions about the example datasets and apply skills introduced in the module to answer them. TAME 2.0 effectiveness was evaluated via participant surveys during graduate-level workshops and coursework, as well as undergraduate-level summer research training events, and suggested edits were incorporated while overall metrics of effectiveness were quantified.DiscussionCollectively, TAME 2.0 now serves as a valuable resource to address the growing demand of increased data science training in environmental health research. TAME 2.0 is publicly available at: https://uncsrp.github.io/TAME2/.

PurposeThe purpose of this study was to examine the effects of a 7-week supplemental BFR training intervention on both acute and chronic alterations in salivary testosterone (sTes) and cortisol (sCort) in collegiate American football players.Methods58 males were divided into 4 groups: 3 completed an upper- and lower-body split resistance training routine (H, H/S, H/S/R; H = Heavy, S = Supplemental, R = BFR), with H/S/R performing end-of-session practical BFR training, and H/S serving as the volume-matched non-BFR group. The final group (M/S/R) completed modified resistance training programming with the same practical BFR protocol as H/S/R. Athletes were further split into AM and PM training groups based upon their pre-determined training schedules, in cooperation with University strength and conditioning staff. Practical BFR consisted of end-of-session barbell bench press and back squat using 20% 1 repetition maximum (1RM) for 30-20-20-20 repetitions across 4 sets, with 45-seconds rest. Saliva samples were taken pre- and post- the first lower-body training sessions in week 1 and week 7 (i.e., test 1 and test 2) of the program, yielding four total. sTes and sCort were analyzed using 4-way (4 × 2 × 2 × 2) mixed model ANOVA’s.ResultsHormonal variables all exhibited main effects for time-of-day (p < 0.001). A significant group × time interaction effect (F3,50 = 3.246, p < 0.05) indicated increases in sTes post-training cycle for the H/S/R group only. Further, PM post-exercise sCort decreased from test 1 to test 2 (nmol·L−1: 95% CI: PM test 1 post-exercise = 10.7–17.1, PM test 2 post-exercise = 5.0–8.9). For the testosterone-to-cortisol ratio (T/C), AM pre-exercise was lower than PM (p < 0.05), with no change in post-exercise T/C for both AM and PM conditions when collapsed across testing times.DiscussionOverall, these findings suggest an ecologically valid method of BFR implementation is capable of inducing heightened concentrations of sTes in well-resistance trained American football athletes, providing additional insight on possible physiological mechanisms underpinning BFR’s ability to elicit beneficial muscle hypertrophy and maximal strength adaptations when performed during regimented training programs. Additionally, notable rises in T/C, and a null sCort response post-exercise were observed post-program for all groups, possibly indicative of positive physiological adaptation.

Prenatal exposure to metals can influence fetal programming via DNA methylation and has been linked to adverse birth outcomes and long-term consequences. Epigenetic clocks estimate the biological age of a given tissue based on DNA methylation and are potential health biomarkers. This study leveraged the Extremely Low Gestational Age Newborn (ELGAN) study (n = 265) to evaluate associations between umbilical cord tissue concentrations of 11 metals as single exposures as well as mixtures in relation to (1) placental epigenetic gestational age acceleration (eGAA) and the (2) methylation status of the Robust Placental Clock (RPC) CpGs. Linear mixed effect regression models were stratified by infant sex. Both copper (Cu) and manganese (Mn) were significantly associated with a decelerated placental eGA of −0.98 (95% confidence interval (CI): −1.89, −0.07) and −0.90 weeks (95% CI: −1.78, −0.01), respectively, in male infants. Cu and Mn levels were also associated with methylation at RPC CpGs within genes related to processes including energy homeostasis and inflammatory response in placenta. Overall, these findings suggest that prenatal exposures to Cu and Mn impact placental eGAA in a sex-dependent manner in ELGANs, and future work could examine eGAA as a potential mechanism mediating in utero metal exposures and later life consequences.

Given the increasing use of innovative force plate systems in applied sports settings and the impact that anterior cruciate ligament (ACL) injuries have on team success, the purpose of the present study was to compare the lower-body neuromuscular performance characteristics of athletes who underwent ACL reconstruction (ACLR) and their non-injured counterparts (i.e., healthy controls). Forty-five male (thirteen injured) and twenty-six female (ten injured) semi-professional soccer players volunteered to participate in the present study. Each athlete performed three countermovement vertical jumps (CMJs) while standing on a uniaxial force plate system sampling at 1000 Hz. The injured athletes completed a nine-month recovery protocol and were screened 11–13 months post-ACLR. The dependent variables included the force–time metrics within both the eccentric and concentric phases of the CMJ. Independent t-tests or Mann–Whitney U-test were used to examine statistically significant (p < 0.05) differences in each variable (i.e., ACL-injured vs. healthy controls). The results revealed no significant between-group differences in any CMJ force–time metrics of interest (e.g., concentric peak force, eccentric mean power, countermovement depth) between ACL-injured and non-injured athletes, including inter-limb asymmetry measures (i.e., peak takeoff and landing force). Besides implying the effectiveness of the implemented rehabilitation protocol, these findings suggest that the CMJ may not present a sufficient neuromuscular performance stimulus needed to expose lower-limb asymmetries and strength and power deficiencies 11–13 months post-ACLR.

This study investigated the endocrine responses to accentuated eccentric loading (AEL) paired with cluster sets (CSs) versus traditional training (TRAD). Seventeen recreationally active subjects (male = 11, females = 6, age = 23.18 ± 4.15 yrs, height = 1.72 ± 0.1 m, body mass = 81.29 ± 22.18 kg, back squat-to-body mass ratio = 1.55 ± 0.33, and bench press-to-body mass ratio = 1.06 ± 0.28) were randomly allocated into AEL and TRAD groups and trained for 4 weeks. The training was performed during a strength–endurance block with the target load consisting of three sets of 10 repetitions. The AEL group performed three sets of 10 for the squat and bench press using AEL every other repetition (5 AEL repetitions per set). In this protocol, CSs were also performed as one AEL repetition plus one traditional repetition followed by 15 s rest. Resistance training was performed three days a week, whilst sprint and agility training were performed two days a week. Testosterone (T), cortisol (C), creatinine (CREA), fat mass (FM), and fat-free mass (FFM) were assessed pre- and post-test. With a series of 2 × 2 repeated-measure ANOVA, the differences in the means between the two training methods and across time were compared. No statistically significant differences in resting blood variables or body composition were observed between the AEL and TRAD protocols after 4 weeks of training. Whilst the results marginally favored the use of AEL, these results did not support significant improvements in body composition or hormonal responses.

Abstract Background Although survival rates for infants born extremely preterm (gestation

Abstract Pre-pregnancy body mass index (BMI) is associated with adverse pregnancy and neonatal health outcomes, with differences in risk observed between sexes. Given that the placenta is a sexually dimorphic organ and critical regulator of development, examining differences in placental mRNA and miRNA expression in relation to pre-pregnancy BMI may provide insight into responses to maternal BMI in utero. Here, genome-wide mRNA and miRNA expression levels were assessed in the placentas of infants born extremely preterm. Differences in expression were evaluated according to pre-pregnancy BMI status (1) overall and (2) in male and female placentas separately. Overall, 719 mRNAs were differentially expressed in relation to underweight status. Unexpectedly, no genes were differentially expressed in relation to overweight or obese status. In male placentas, 572 mRNAs were associated with underweight status, with 503 (70%) overlapping genes identified overall. Notably, 43/572 (8%) of the mRNAs associated with underweight status in male placentas were also gene targets of two miRNAs (miR-4057 and miR-128-1-5p) associated with underweight status in male placentas. Pathways regulating placental nutrient metabolism and angiogenesis were among those enriched in mRNAs associated with underweight status in males. This study is among the first to highlight a sexually dimorphic response to low pre-pregnancy BMI in the placenta.

Mikkelsen et al. demonstrate molecular and cellular evidence of the evolution of xyloglucan (XyG), a structural component of the cell walls of most land plants, in charophyte algae. This study describes the structure of XyG in charophyte algae, including identification of fucosylated XyG, and furthermore identifies orthologs required to produce XyG.

Abstract Background An unusual feature of SARS-Cov-2 infection and the COVID-19 pandemic is that children are less severely affected than adults. This is especially paradoxical given the epidemiological links between poor air quality and increased COVID-19 severity in adults and that children are generally more vulnerable than adults to the adverse consequences of air pollution. Objectives To identify gaps in knowledge about the factors that protect children from severe SARS-Cov-2 infection even in the face of air pollution, and to develop a transdisciplinary research strategy to address these gaps. Methods An international group of researchers interested in children’s environmental health was invited to identify knowledge gaps and to develop research questions to close these gaps. Discussion Key research questions identified include: what are the effects of SAR-Cov-2 infection during pregnancy on the developing fetus and child; what is the impact of age at infection and genetic susceptibility on disease severity; why do some children with COVID-19 infection develop toxic shock and Kawasaki-like symptoms; what are the impacts of toxic environmental exposures including poor air quality, chemical and metal exposures on innate immunity, especially in the respiratory epithelium; what is the possible role of a “dirty” environment in conveying protection – an example of the “hygiene hypothesis”; and what are the long term health effects of SARS-Cov-2 infection in early life. Conclusion A concerted research effort by a multidisciplinary team of scientists is needed to understand the links between environmental exposures, especially air pollution and COVID-19. We call for specific research funding to encourage basic and clinical research to understand if/why exposure to environmental factors is associated with more severe disease, why children appear to be protected, and how innate immune responses may be involved. Lessons learned about SARS-Cov-2 infection in our children will help us to understand and reduce disease severity in adults, the opposite of the usual scenario.

Abstract Background Children born extremely preterm are at heightened risk for intellectual and social impairment, including Autism Spectrum Disorder (ASD). There is increasing evidence for a key role of the placenta in prenatal developmental programming, suggesting that the placenta may, in part, contribute to origins of neurodevelopmental outcomes. Methods We examined associations between placental transcriptomic and epigenomic profiles and assessed their ability to predict intellectual and social impairment at age 10 years in 379 children from the Extremely Low Gestational Age Newborn (ELGAN) cohort. Assessment of intellectual ability (IQ) and social function was completed with the Differential Ability Scales-II and Social Responsiveness Scale (SRS), respectively. Examining IQ and SRS allows for studying ASD risk beyond the diagnostic criteria, as IQ and SRS are continuous measures strongly correlated with ASD. Genome-wide mRNA, CpG methylation and miRNA were assayeds with the Illumina Hiseq 2500, HTG EdgeSeq miRNA Whole Transcriptome Assay, and Illumina EPIC/850 K array, respectively. We conducted genome-wide differential analyses of placental mRNA, miRNA, and CpG methylation data. These molecular features were then integrated for a predictive analysis of IQ and SRS outcomes using kernel aggregation regression. We lastly examined associations between ASD and the multi-omic-predicted component of IQ and SRS. Results Genes with important roles in neurodevelopment and placental tissue organization were associated with intellectual and social impairment. Kernel aggregations of placental multi-omics strongly predicted intellectual and social function, explaining approximately 8% and 12% of variance in SRS and IQ scores via cross-validation, respectively. Predicted in-sample SRS and IQ showed significant positive and negative associations with ASD case–control status. Limitations The ELGAN cohort comprises children born pre-term, and generalization may be affected by unmeasured confounders associated with low gestational age. We conducted external validation of predictive models, though the sample size (N = 49) and the scope of the available out-sample placental dataset are limited. Further validation of the models is merited. Conclusions Aggregating information from biomarkers within and among molecular data types improves prediction of complex traits like social and intellectual ability in children born extremely preterm, suggesting that traits within the placenta-brain axis may be omnigenic.

The identification of sport and position-specific key performance indicators has been of increased interest to practitioners working within high performance sport settings. The aim of this study was to create statistical models, across a spectrum of position groups, that explain the largest amount of variance in on-field performance over four collegiate American football seasons. A total of four position groups were analyzed, including Wide Receiver/Tight End (n = 29), Running Backs (n = 8), Linebacker/Defensive Line (n =41), Defensive Backs (n = 28). Different tests of physical performance (back squat, bench press, hang clean, 40-yard dash, pro-agility, L-drill, vertical jump, and broad jump) were set as the independent variables, while a Total Score of On-Field Performance, consisting of position-specific game statistics was set as the dependent variable. Linear mixed models, using backwards model selection were used to identify models that best fit the position-specific data. Results revealed that models consisted of at least three different physical performance test, were position-specific, and explained the variance in on-field performance to different degrees. Significant correlations were found between physical performance models and on-field performance. Results from our study may be of interest to practitioners working within American football that are interested in maximizing success through and individual approach towards the implementation of training.

MicroRNAs (miRNAs) are epigenetic modifiers that play an important role in the regulation of the expression of genes across the genome. miRNAs are expressed in the placenta as well as other organs, and are involved in several biological processes including the regulation of trophoblast differentiation, migration, invasion, proliferation, apoptosis, angiogenesis and cellular metabolism. Related to their role in disease process, miRNAs have been shown to be differentially expressed between normal placentas and placentas obtained from women with pregnancy/health complications such as preeclampsia, gestational diabetes mellitus, and obesity. This dysregulation indicates that miRNAs in the placenta likely play important roles in the pathogenesis of diseases during pregnancy. Furthermore, miRNAs in the placenta are susceptible to altered expression in relation to exposure to environmental toxicants. With relevance to the placenta, the dysregulation of miRNAs in both placenta and blood has been associated with maternal exposures to several toxicants. In this review, we provide a summary of miRNAs that have been assessed in the context of human pregnancy-related diseases and in relation to exposure to environmental toxicants in the placenta. Where data are available, miRNAs are discussed in their context as biomarkers of exposure and/or disease, with comparisons made across-tissue types, and conservation across studies detailed.

Basketball is one of the most popular sports worldwide. The basketball dunk uses a very powerful jumping motion to forcefully push a basketball through a goal positioned at a height of 10 feet (3.05m). In the modern game of basketball, the dunk is very popular due to its very high field goal percentage. Due to lack of research on this event, the purpose of this study was to examine the kinetic variables of peak force, peak power, rate of force development, impulse and time during the concentric phase of the five most commonly used variations of a basketball dunk: one-leg left (1LL), one-leg right (1LR), two-leg left-right (2LLR), two-leg right-left (2LRL) and two leg stationary (2LS). Ten healthy recreationally active men (X±SD, age=22.4±2.5, weight=89±6.3kg, height=192.8±4.9cm, vertical jump=73.7±12.4cm) who were capable of dunking a basketball volunteered to participate in this research study. Kinetic variables measured in this study were obtained from a force plate and data acquisition system sampling at 1000Hz. Based on our data we conclude that the basketball dunk is a very powerful activity that requires high levels of strength and power. Our data suggest that the most time consuming dunk approach was a 2LS (0.820±0.116sec) while the fastest dunk approach was 1LL (0.311±0.039sec), which can serve as a guideline for which dunk should be utilized at certain times during an on-court game performance. The highest peak power output was observed for 2LS (6261.9±1104.1W) which also had the lowest rate of force development (5851.3±3069.5N/sec) and impulse (408.2±41.1N/sec). The highest peak forces were observed for 2LLR (3158.4±376.3N) and 2LRL (3206.8±518.2N) dunk approaches. Knowing the specific biomechanical characteristics of a motion can help target optimal training for each individual and lead to enhanced basketball performance, specifically the basketball dunk in this case. In conclusion, this study serves as a foundation and guideline for further research by presenting the previously unexplored kinetic and kinematic variables of a basketball dunk.

Background and study aims Information about the endoscopic characterization of small bowel gastrointestinal tumors (GISTs) is limited. The aim of this case study was to describe the endoscopic spectrum of small bowel GISTs and to present a practical classification. Patients and methods Observational, retrospective, consecutive case series of patients with small bowel GIST. Results A total of 10 small bowel GISTs were found in patients (6 male, 4 female, mean age 52 years, range 28 to 68).). All patients presented with obscure gastrointestinal bleeding (overt, n = 8, occult, n = 2). Most GISTs were present in the proximal or middle small bowel (n = 7). The endoscopic tumor characteristics could be categorized as follows: submucosal round (n = 4), submucosal sessile (n = 2), and invasive/penetrating) (n = 4). The mucosa overlying the tumor was normal (n = 4), grooved (n = 3) or frankly ulcerated (n = 3). Tumor size ranged from 8 mm to 50 mm. Biopsy was negative in all patients with normal mucosa but showed tumor in all patients with ulcerations. Regardless of biopsy results, all patients were sent for surgery. Nine resections were carried out. One patient refused surgery. There were no complications of endoscopy in this cohort. Conclusion Our series shows that GISTs have a wider spectrum of endoscopic characteristics than previously described. The round type with normal overlying mucosa was equally prevalent as the grooved or ulcerated variant. Endoscopists should be aware of this wide spectrum of presentation of small bowel GIST.

Abstract Background The Toxicological Priority Index (ToxPi) is a method for prioritization and profiling of chemicals that integrates data from diverse sources. However, individual data sources (“assays”), such as in vitro bioassays or in vivo study endpoints, often feature sections of missing data, wherein subsets of chemicals have not been tested in all assays. In order to investigate the effects of missing data and recommend solutions, we designed simulation studies around high-throughput screening data generated by the ToxCast and Tox21 programs on chemicals highlighted by the Agency for Toxic Substances and Disease Registry’s (ATSDR) Substance Priority List (SPL), which helps prioritize environmental research and remediation resources. Results Our simulations explored a wide range of scenarios concerning data (0-80% assay data missing per chemical), modeling (ToxPi models containing from 160-700 different assays), and imputation method (k-Nearest-Neighbor, Max, Mean, Min, Binomial, Local Least Squares, and Singular Value Decomposition). We find that most imputation methods result in significant changes to ToxPi score, except for datasets with a small number of assays. If we consider rank change conditional on these significant changes to ToxPi score, we find that ranks of chemicals in the minimum value imputation, SVD imputation, and kNN imputation sets are more sensitive to the score changes. Conclusions We found that the choice of imputation strategy exerted significant influence over both scores and associated ranks, and the most sensitive scenarios were those involving fewer assays plus higher proportions of missing data. By characterizing the effects of missing data and the relative benefit of imputation approaches across real-world data scenarios, we can augment confidence in the robustness of decisions regarding the health and ecological effects of environmental chemicals

Atmospheric oxidation of isoprene, the most abundant non-methane hydrocarbon emitted into Earth's atmosphere primarily from terrestrial vegetation, is now recognized as a major contributor to the global secondary organic aerosol (SOA) burden. Anthropogenic pollutants significantly enhance isoprene SOA formation through acid-catalyzed heterogeneous chemistry of epoxide products. Since isoprene SOA formation as a source of fine aerosol is a relatively recent discovery, research is lacking on evaluating its potential adverse effects on human health. The objective of this study was to examine the effect of isoprene-derived SOA on inflammation-associated gene expression in human lung cells using a direct deposition exposure method. We assessed altered expression of inflammation-related genes in human bronchial epithelial cells (BEAS-2B) exposed to isoprene-derived SOA generated in an outdoor chamber facility. Measurements of gene expression of known inflammatory biomarkers interleukin 8 (IL-8) and cyclooxygenase 2 (COX-2) in exposed cells, together with complementary chemical measurements, showed that a dose of 0.067 µg cm−2 of SOA from isoprene photooxidation leads to statistically significant increases in IL-8 and COX-2 mRNA levels. Resuspension exposures using aerosol filter extracts corroborated these findings, supporting the conclusion that isoprene-derived SOA constituents induce the observed changes in mRNA levels. The present study is an attempt to examine the early biological responses of isoprene SOA exposure in human lung cells.

Background: Prenatal exposure to inorganic arsenic (iAs) is associated with dysregulated fetal gene and protein expression. Potential biological mechanisms that underlie these changes include, but are not limited to, changes to the epigenome. Objective: The aim of the present study was to identify whether the expression of key genes, proteins, or both and their associated biological pathways are perturbed by compiling datasets from studies on prenatal arsenic exposure. Methods: We compiled datasets from 12 studies that analyzed the relationship between prenatal iAs exposure and changes to the fetal epigenome (5-methyl cytosine), transcriptome (mRNA expression), and/or proteome (protein expression). Findings: Across the 12 studies, a set of 845 unique genes was identified and found to enrich for their role in biological pathways, including the peroxisome proliferator-activated receptor, nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, and the glucocorticoid receptor. Tumor necrosis factor was identified as a putative cellular regulator underlying most (n = 277) of the identified iAs-associated gene or protein expression changes. Conclusions: The identification of the common set of genes across numerous human cohorts suggests a conserved biological response to prenatal arsenic exposure. The genes/proteins and their associated pathways may be useful in future mechanistic investigations of iAs associated diseases.