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There is currently an unmet need in higher education for a structured, pre-emptive programme of support to help students enhance their resilience to stress. This article presents a mixed-methods evaluation of a transferable biopsychosocial resilience intervention for students -- the "Resilience Enhancement Programme for Students" (REP-S). In Study 1, a randomised control trial showed that participating in the intervention was associated with significantly decreased perceived stress, decreased trait neuroticism and enhanced self-esteem over a period of one month. In Study 2, written and focus-group qualitative data from students provided evidence that the intervention led to perceived positive changes, including sleeping better, dealing more effectively with assessments and managing interpersonal challenges. Future steps in the evaluation of the REP-S are discussed.

Given the paucity of information on local tissue water (LTW) in the upper extremity and trunk of women after breast cancer surgery, the purpose of this study was to compare tissue dielectric constant (TDC) values between the affected and unaffected sides of breast cancer survivors with and without upper extremity lymphoedema (LE). Differences in LTW were assessed using the TDC method for three sites in the upper limbs, three sites in the lateral thorax and two sites on the back. Additional measures included demographic and clinical characteristics, arm circumference and bioimpedance analysis. For the 112 survivors without LE, no differences in TDC values were found between the affected and unaffected sides for the first dorsal web space, ventral forearm and upper arm, and upper and lower back. Compared to the unaffected side, TDC values were significantly higher on the affected side for the upper, mid and lower lateral thorax. For the 78 survivors with LE, compared to the unaffected side, TDC was significantly higher on the affected side for all of the sites evaluated except the hand web space. Our findings support the use of the TDC method to detect differences in upper extremity and truncal oedema in survivors with LE following breast cancer treatment. Measurement of LTW may provide a useful method to determine truncal as well as extremity LE. The ability to detect early signs of truncal oedema may lead to pre-emptive interventions in breast cancer survivors.

Per- and polyfluoroalkyl substances (PFAS) are a widespread and persistent class of contaminants posing significant environmental and human health concerns. Comprehensive understanding of the modes of action underlying toxicity among structurally diverse PFAS is mostly lacking. To address this need, we recently reported on our application of developing zebrafish to evaluate a large library of PFAS for developmental toxicity. In the present study, we prioritized 15 bioactive PFAS that induced significant morphological effects and performed RNAsequencing to characterize early transcriptional responses at a single timepoint (48 h post fertilization) after early developmental exposures (8 h post fertilization). Internal concentrations of 5 of the 15 PFAS were measured from pooled whole fish samples across multiple timepoints between 24-120 h post fertilization, and additional temporal transcriptomics at several timepoints (48-96 h post fertilization) were conducted for Nafion byproduct 2. A broad range of differentially expressed gene counts were identified across the PFAS exposures. Most PFAS that elicited robust transcriptomic changes affected biological processes of the brain and nervous system development. While PFAS disrupted unique processes, we also found that similarities in some functional head groups of PFAS were associated with the disruption in expression of similar gene sets. Body burdens after early developmental exposures to select sulfonic acid PFAS, including Nafion byproduct 2, increased from the 24-96 h post fertilization sampling timepoints and were greater than those of sulfonamide PFAS of similar chain lengths. In parallel, the Nafion byproduct 2-induced transcriptional responses increased between 48 and 96 h post fertilization. PFAS characteristics based on toxicity, transcriptomic effects, and modes of action will contribute to further prioritization of PFAS structures for testing and informed hazard assessment. [ABSTRACT FROM AUTHOR]

The fate of per and polyfluoroalkyl substances (PFASs) in aqueous filmforming foams (AFFFs) under anaerobic conditions has not been well characterized, leaving major gaps in our understanding of PFAS fate and transformation at contaminated sites. In this study, the biotransformation of 6:2 fluorotelomer thioether amido sulfonate (6:2 FtTAoS), a component of several AFFF formulations, was investigated under sulfate-reducing conditions in microcosms inoculated with either pristine or AFFF-impacted solids. To identify the transformation products, we used high-resolution mass spectrometry and employed suspect-screening and nontargeted compound identification methods. These analyses demonstrated that 6:2 FtTAoS was transformed primarily to a stable polyfluoroalkyl compound, 6:2 fluorotelomer thioether propionate (6:2 FtTP). It did not undergo further reactions to produce the perfluoroalkyl carboxylates and fluorotelomer sulfonates and carboxylates that were observed during aerobic transformations. Here, the 6:2 FtTP was recalcitrant to biotransformation, indicating the stability of the thioether group under sulfate reducing conditions. The total oxidizable precursor (TOP) assay was used to assess the presence of other PFASs. Although nearly all of the PFAS mass initially present was recovered from the pristine microcosms, only 67% of the initial PFAS mass was recovered from the contaminated microcosms, suggesting the formation of volatile biotransformation products or those that could not be detected by the TOP assay.

Per‐ and polyfluoroalkyl substances (PFAS) encompass a large group of recalcitrant anthropogenic compounds that have been used in a variety of consumer and industrial products and processes over many decades. Drinking water standards were recently finalized for two PFAS at low nanogram per liter concentrations. Due to the widespread use of PFAS and low health‐based thresholds, a literature review and laboratory and field studies were conducted to assess several potential sources of bias in PFAS concentrations. Fluoropolymers are commonly present in equipment, products, and materials used during field sampling, potentially leading to false positive results. Laboratory results confirmed the presence of PFAS in multiple commonly used field materials. However, best practices can be used to limit pathways for cross contamination. Laboratory‐specified hold times and sample storage temperatures are scientifically founded and adequately prevent bias due to PFAS sorption to sampling containers or partial degradation of some PFAS to form others. PFAS are also known to accumulate at the air‐water interface and other interfaces. Results from laboratory and field studies indicate that PFAS enrichment in foam and in the surface microlayer does occur. However, the effect of this phenomenon is within the range of analytical and spatial sampling variability and therefore a change in sampling procedures is not needed. Findings were distilled into science‐based and practical recommendations to minimize bias during PFAS sampling without incurring unnecessary cost and effort. [ABSTRACT FROM AUTHOR]

The aerobic biotransformation pathways of 4:2, 6:2, and 8:2 fluorotelomer thioether amido sulfonate (FtTAoS) were characterized by determining the fate of the compounds in soil and medium microcosms amended with an aqueous film-forming foam (AFFF) solution. The biotransformation of FtTAoS occurred in live microcosms over approximately 40 days and produced 4:2, 6:2, and 8:2 fluorotelomer sulfonate (FtS), 6:2 fluorotelomer unsaturated carboxylic acid (FtUCA), 5:3 fluorotelomer carboxylic acid (FtCA), and C4 to C8 perfluorinated carboxylic acids (PFCAs). Two biotransformation products corresponding to singly and doubly oxygenated forms of 6:2 FtTAoS were also identified through high resolution mass spectrometry (MS) analysis and liquid chromatography tandem-MS. An oxidative assay was used to indirectly quantify the total concentration of polyfluorinated compounds and check the mass balance. The assay produced near complete mass recovery of FtTAoS after biotransformation, with 10% (mol/mol) of the amended FtTAoS accounted for in FtS, FtCA, and PFCA products. The transformation rates of identified products appear to be slow relative to FtTAoS, indicating that some intermediates may persist in the environment. This study confirms some of the sources of FtS and PFCAs in groundwater and soil at AFFF-impacted sites and suggests that fluorinated intermediates that are not routinely measured during the biotransformation of PFASs may accumulate.

Significant investments have been made to develop treatment technologies, particularly destructive approaches, for a variety of per‐ and polyfluoroalkyl substances (PFAS) that are present in groundwater, surface water, and other environmental media. A multiple lines of evidence approach were developed to assist regulators, funding agencies, and practitioners in evaluating PFAS treatment technology performance. This article describes each of three lines of evidence that a technology is effective: (1) decrease in target PFAS concentrations is observed; (2) PFAS treatment transformation products are identified and quantified; and (3) a treatment mechanism is proposed that is consistent with previous studies and supported by data. Other considerations are also described to inform conclusions about knowledge gaps and priorities for future testing. Collectively, these lines of evidence and other considerations help communicate the complexities of PFAS treatment, strengthen research plans, standardize technology evaluator reviews, and inform realistic expectations of PFAS treatment technologies. [ABSTRACT FROM AUTHOR]

The purpose was to examine relationships between external loads (ELs), perceived exertion, and soreness. Collegiate men soccer players (n = 19) were monitored for 72 sessions (training: n = 53; matches: n = 19). Likert scale assessments (0-6) of lower body soreness were collected prior to each session, and ELs were collected using positional monitoring technology. Session rate of perceived exertion (sRPE-load) was calculated by multiplying perceived exertion values (Borg CR-10 Scale) by respective session duration to determine internal load. Multiple analyses of variance were used to determine differences in ELs across seasons (preseason, in-season, post-season) and sessions (training, match). Bivariate Pearson correlation coefficients and linear regression analyses were used to evaluate relationships among soreness, ELs, and sRPE-load. Greatest ELs were observed during pre-season and post-season phases (p < 0.001). Sessions with high perceived exertion and low soreness were associated with higher ELs (p < 0.05). Duration (t = 16.13), total distance (t = 9.17), sprint distance (t = 7.54), player load (t = 4.22), top speed (t = 4.69), and acceleration (t = 2.02) positively predicted sRPE-load (F = 412.9, p < 0.001, R² = 0.75). Soreness was weakly and trivially correlated with ELs (p < 0.05). The very strong relationship between ELs and sRPE-load highlights the utility of sRPE-load as a practical means to estimate workload; however, more research into the relationship between soreness and workload is warranted. [ABSTRACT FROM AUTHOR]