Use of δ18Oatm in dating a Tibetan ice core record of Holocene/Late Glacial climate.

Ice cores from the northwestern Tibetan Plateau (NWTP) contain long records of regional climate variability, but refrozen meltwater and dust in these cores has hampered development of robust timescales. Here, we introduce an approach to dating the ice via the isotopic composition of atmospheric O2 in air bubbles (δ18Oatm), along with annual layer counting and radiocarbon dating. We provide a robust chronology for water isotope records (δ18Oice and d-excess) from three ice cores from the Guliya ice cap in the NWTP. The measurement of δ18Oatm, although common in polar ice core timescales, has rarely been used on ice cores from low-latitude, high-altitude glaciers due to (1) low air pressure, (2) the common presence of refrozen melt that adds dissolved gases and reduces the amount of air available for analysis, and (3) the respiratory consumption of molecular oxygen (O2) by micro-organisms in the ice, which fractionates the δ18O of O2 from the atmospheric value. Here, we make corrections for melt and respiration to address these complications. The resulting records of water isotopes from the Guliya ice cores reveal climatic variations over the last 15,000 y, the timings of which correspond to those observed in independently dated lake and speleothem records and confirm that the Guliya ice cap existed before the Holocene. The millennial-scale drivers of δ18Oice are complex and temporally variable; however, Guliya δ18Oice values since the mid-20th century are the highest since the beginning of the Holocene and have increased with regional air temperature.

Disappearance of the last tropical glaciers in the Western Pacific Warm Pool (Papua, Indonesia) appears imminent.

The glaciers near Puncak Jaya in Papua, Indonesia, the highest peak between the Himalayas and the Andes, are the last remaining tropical glaciers in the West Pacific Warm Pool (WPWP). Here, we report the recent, rapid retreat of the glaciers near Puncak Jaya by quantifying the loss of ice coverage and reduction of ice thickness over the last 8 y. Photographs and measurements of a 30-m accumulation stake anchored to bedrock on the summit of one of these glaciers document a rapid pace in the loss of ice cover and a ∼5.4-fold increase in the thinning rate, which was augmented by the strong 2015-2016 El Niño. At the current rate of ice loss, these glaciers will likely disappear within the next decade. To further understand the mechanisms driving the observed retreat of these glaciers, 2 ∼32-m-long ice cores to bedrock recovered in mid-2010 are used to reconstruct the tropical Pacific climate variability over approximately the past half-century on a quasi-interannual timescale. The ice core oxygen isotopic ratios show a significant positive linear trend since 1964 CE (0.018 ± 0.008‰ per year; P < 0.03) and also suggest that the glaciers' retreat is augmented by El Niño-Southern Oscillation processes, such as convection and warming of the atmosphere and sea surface. These Papua glaciers provide the only tropical records of ice core-derived climate variability for the WPWP.

A novel, highly discriminatory risk model predicting acute severe right ventricular failure in patients undergoing continuous-flow left ventricular assist device implant.

Various risk models with differing discriminatory power and predictive accuracy have been used to predict right ventricular failure (RVF) after left ventricular assist device (LVAD) placement. There remains an unmet need for a contemporary risk score for continuous flow (CF)-LVADs. We sought to independently validate and compare existing risk models in a large cohort of patients and develop a simple, yet highly predictive risk score for acute, severe RVF. Data from the Mechanical Circulatory Support Research Network (MCSRN) registry, consisting of patients who underwent CF-LVAD implantation, were randomly divided into equal-sized derivation and validation samples. RVF scores were calculated for the entire sample, and the need for a right ventricular assist device (RVAD) was the primary endpoint. Candidate predictors from the derivation sample were subjected to backward stepwise logistic regression until the model with lowest Akaike information criterion value was identified. A risk score was developed based on the identified variables and their respective regression coefficients. Between May 2004 and September 2014, 734 patients underwent implantation of CF-LVADs [HeartMate II LVAD, 76% (n = 560), HeartWare HVAD, 24% (n = 174)]. A RVAD was required in 4.5% (n = 33) of the patients [Derivation cohort, n = 15 (4.3%); Validation cohort, n = 18 (5.2%); P = 0.68)]. 19.5% of the patients (n = 143) were female, median age at implant was 59 years (IQR, 49.4-65.3), and median INTERMACS profile was 3 (IQR, 2-3). RVAD was required in 4.5% (n = 33) of the patients. Correlates of acute, severe RVF in the final model included heart rate, albumin, BUN, WBC, cardiac index, and TR severity. Areas under the curves (AUC) for most commonly used risk predictors ranged from 0.61 to 0.78. The AUC for the new model was 0.89 in the derivation and 0.92 in the validation cohort. Proposed risk model provides very high discriminatory power predicting acute severe right ventricular failure and can be reliably applied to patients undergoing placement of contemporary continuous flow left ventricular assist devices.

Ventricular Assist Device Therapy in Older Patients With Heart Failure: Characteristics and Outcomes.

BACKGROUND: Limited data exist on outcomes in patients ≥70 years of age supported with the use of continuous-flow left ventricular assist devices (LVADs). METHODS: Data on 1149 continuous-flow LVAD recipients was queried from the Mechanical Circulatory Support Research Network. Groups were assigned based on age: ≥70 years ("older patients") and <70 years. The primary outcome was survival at one-year based on age grouping. RESULTS: Compared with younger patients (54.3 ± 11.2 y; n = 986), older patients (73.4 ± 3.0 y) constituted only 14% of LVAD implants. Older patients had similar rates of device thrombosis (P = .47) and stroke (P = .44), but survival-free of gastrointestinal bleeding (GIB) at 1 year was lower compared with younger patients (58% vs 69%; P < .01). Unadjusted survival at 1 year in older patients was 75% compared with 84% in younger patients, and at 2 years 65% versus 73% (P = .18). Age ≥70 years was not associated with increased mortality (adjusted hazard ratio [aHR] 0.94, 95% confidence interval [CI] 0.70-1.26; P = .67). Preoperative creatinine (aHR 1.57, 95% CI: 1.30-1.89, P < .0001), bilirubin (aHR 1.22, 95% CI 1.05-1.42; P = .010), and ischemic cardiomyopathy (aHR 1.43, 95% CI 1.11-1.84; P = .005) portended increased risk of death. In older patients, the only predictor of mortality was creatinine (HR 2.1, 95% CI 1.2-3.4; P = .007). Creatinine ≥1.4 mg/dL was associated with a 1-year survival of 65%, compared with 84% when the creatinine was <1.4 mg/dL (P = .009). CONCLUSION: Age >70 years is an important consideration when assessing LVAD risk, but other correlates may be more predictive of LVAD survival. Older patients without renal dysfunction have survival similar to younger patients. Older patients should be counseled about age-correlated risks, including higher rates of GIB.

Minimally invasive thoracic left ventricular assist device implantation; case series demonstrating an integrated multidisciplinary strategy.

OBJECTIVES: The present report describes the authors' initial experience with implantation of the Heartware left ventricular assist devices (HeartWare Inc., Framingham, MA). via a minimally invasive surgical approach without cardiopulmonary bypass. A detailed overview of the anesthesiologist's role during the procedure, characteristics of the patient population, and short-term clinical outcomes are provided, and the clinical considerations that influence the decision to implant this device via an off-pump minimally invasive approach are outlined. DESIGN: Retrospective medical record review. SETTING: University hospital. PARTICIPANTS: Thirteen patients with advanced heart failure deemed candidates for off-pump minimally invasive left ventricular Heartware implantation as a bridge to heart transplantation. INTERVENTIONS: The Heartware left ventricular assist device was implanted in all 13 patients via a minimally invasive approach. MEASUREMENTS AND MAIN RESULTS: One patient required unplanned cardiopulmonary bypass to control bleeding around the left ventricular outflow cannula. The average operating room time was 249.8 minutes±46.2 minutes. Six of 13 patients required no intraoperative red blood cell transfusions. Seven patients were extubated within 12 hours after surgery. Two patients required reintubation within 48 hours. No patients required reoperation for bleeding. Average intensive care unit and hospital lengths of stay were 7.2±3.9 days and 13.4±3.6 days, respectively. There were no in-hospital deaths. CONCLUSIONS: Minimally invasive off-pump left ventricular Heartware implantation is an emerging alternative to placement by midline sternotomy. The authors speculate, based on their limited experience, that an off-pump thoracic strategy may be a desirable option for some patients and that clinical outcomes may be non-inferior to placement by midline sternotomy with cardiopulmonary bypass.

Hemodynamic transesophageal echocardiography after left ventricular assist device implantation.

OBJECTIVE: The authors hypothesized that the clinical profile of patients undergoing hTEE after continuous flow left ventricular assist device (CF-LVAD) implant would be in patients with greater acuity, more blood product utilization, and longer length of ICU stay, and that hTEE would change clinical management. DESIGN: Retrospective review. SETTING: University hospital. PARTICIPANTS: One hundred consecutive patients receiving a CF-LVAD. INTERVENTIONS: Retrospective review using a standardized electronic form of a miniaturized disposable transesophageal echocardiography probe that documented not only physical findings but also changes in hemodynamic management (hTEE) in CF-LVAD patients. MEASUREMENTS AND MAIN RESULTS: Of the 100 patients, 41 received an hTEE probe. The INTERMACS score, Leitz-Miller Score, and Kormos score indicated the hTEE group had a statistically significant greater risk of morbidity and mortality. Interoperatively, the hTEE group received more blood products and was more likely to have an open chest. Postoperatively, the hTEE group received more blood products, had a longer total length of stay, and had increased mortality. ICU length of stay, days on inotropes and days on mechanical ventilation were not statistically significant between the 2 groups. Information obtained from hTEE changed ICU management in 72% of studies. CONCLUSION: Retrospective review of CF-LVAD patients revealed that postoperative hTEE is used in sicker CF-LVAD patients and frequently leads to changes in ICU clinical management.

Comparison of time-matched aerobic, resistance or combined exercise training in women living with obesity: The EXOFFIT study.

Background: Improvements in cardiorespiratory fitness (CRF) have been shown to largely attenuate the negative health risks associated with obesity. To date, literature on women with obesity has focused upon the evaluation of aerobic-based exercise interventions. Hence, there is a need to evaluate resistance and combined interventions with this cohort. Objective: This study aimed to evaluate the feasibility and efficacy of three exercise modalities in women with obesity for improving CRF, strength, body composition and other health outcomes. Methods: Sixty-seven women with obesity were randomly assigned to the control (CON) or one of three exercise groups (aerobic [AE], resistance [RE], COM). Exercise groups were trained x3 times/week for 12 weeks (up to 150-min/week). Feasibility outcomes included adherence, attendance, recruitment and retention rates and adverse events. Secondary outcomes were CRF (predicted VO2 max), body composition (body weight [BW], waist circumference [WC], body fat percentage [%BF], fat mass [FM] and lean mass) and strength (5RM bench press, leg dynamometry, grip strength) and self-reported measures of physical activity, mood, sleep, pain and quality of life. Results: Findings support the feasibility of all three exercise modalities in terms of adherence, attendance, and retention. Interventions with a resistance component (COM and RE) were associated with the greatest improvements across the broad range of health outcomes measured. Combined was the most promising for body composition outcomes including body mass index (Effect size [ES] = 0.79, p = 0.04), BW (ES = 0.75, p = 0.05), %BF (ES = 0.77, p = 0.04), FM (ES = 0.83, p = 0.03) and WC (ES = 0.90, p = 0.02), physical activity (i.e., moderate physical activity [ES = 0.69, p = 0.07), mood (ES = 0.83, p = 0.03) and sleep (ES = 0.78, p = 0.04). Resistance was most promising for CRF (ES = 1.47, p = 0.002), strength (i.e., bench press [ES = 2.88, p=<0.001]) and pain (i.e., pain severity [ES = 0.40, p = 0.31]). Conclusions: For health outcomes, these results indicate the importance of including a resistance component when prescribing exercise for women with obesity to achieve meaningful improvements. CLINICAL TRIAL REGISTRATION: ISRCTN13517067.

Exploring the acceptability of three time-matched exercise interventions for increasing fitness in women living with obesity: A mixed-methods evaluation of the EXOFFIT study.

Background: The EXOFFIT study compared the effectiveness of three time-matched exercise interventions in women with obesity for improving cardiorespiratory fitness. To best inform future research, evaluation of the interventions' acceptability is needed. Previous research has been inconsistent with methods and reporting of acceptability. Thus, the theoretical framework of acceptability (TFA) can be utilized to ensure that all aspects of acceptability are evaluated. No study to date in women with obesity has utilized the TFA in conjunction with quantitative data (i.e., frequencies of themes) to highlight the aspects of interventions that may be most important for participants. Objective: This study aimed to examine the acceptability of the EXOFFIT program and gain insight into the participants' experience of participation, their perspective on the acceptability of trial procedures and interventions and gather their feedback on program changes. Methods: A mixed-methods approach was employed. Thirty-eight participants who completed the exercise interventions were interviewed and completed a self-reported exit questionnaire. Interviews were transcribed verbatim and analyzed in three phases: emergent themes were agreed upon, then mapped to the TFA constructs and the frequencies of each construct and theme were presented as counts. Data collected from the exit questionnaire were collated and reported using descriptive statistics. Results: All seven TFA constructs were identified in the analysis. The EXOFFIT program was found to have a high level of acceptability, with affective attitude, perceived effectiveness and self-efficacy being the most reported constructs. The burden and opportunity costs associated with the program were mainly related to family commitments and support needed to participate. Any negative impact of participation was noted to be outweighed by the perceived benefits. Conclusions: The results of this study will inform the development of future programs with women with obesity and support the consideration of the TFA constructs from the outset of study design.Clinical Trial Registration Number: ISRCTN13517067.

Ischaemic heart disease mortality and years of work in trucking industry workers.

OBJECTIVES: Evidence from general population-based studies and occupational cohorts has identified air pollution from mobile sources as a risk factor for cardiovascular disease. In a cohort of US trucking industry workers, with regular exposure to vehicle exhaust, the authors previously observed elevated standardised mortality ratios for ischaemic heart disease (IHD) compared with members of the general US population. Therefore, the authors examined the association of increasing years of work in jobs with vehicle exhaust exposure and IHD mortality within the cohort. METHODS: The authors calculated years of work in eight job groups for 30,758 workers using work records from four nationwide companies. Proportional hazard regression was used to examine relationships between IHD mortality, 1985-2000, and employment duration in each job group. RESULTS: HRs for at least 1 year of work in each job were elevated for dockworkers, long haul drivers, pick-up and delivery drivers, combination workers, hostlers, and shop workers. There was a suggestion of an increased risk of IHD mortality with increasing years of work as a long haul driver, pick-up and delivery driver, combination worker, and dockworker. CONCLUSION: These results suggest an elevated risk of IHD mortality in workers with a previous history of regular exposure to vehicle exhaust.

Correlates of physical activity and sedentary behavior in adults living with overweight and obesity: A systematic review.

Overweight and obesity are consistently associated with lower physical activity (PA) levels and greater sedentary behavior (SB) in population studies. To date, no review has evaluated the factors associated with these behaviors in the specific population who have developed obesity/overweight. The aim of this systematic review was to identify the correlates/determinants of SB and PA in adults with overweight and obesity. Five databases were searched for studies, which reported factors or outcomes relating to PA or SB in adults living with overweight/obesity, published from 1980 to 2021. The factors were categorized using a socioecological model, strength, and direction of association. Of 34,058 articles retrieved, 45 studies were included, and 155 factors were identified. Self-efficacy, intrinsic motivation, exercise enjoyment, self-perceived good health, and social support were consistently associated with higher levels of PA. Consistent negative correlations were married females, increased BMI, obesity severity, pain, number of comorbidities, lack of time, energy, and willpower, and hilly terrain. Few studies (n = 12) examined SB, and no evidence for consistent associations were found. This review identified several correlates specific to PA in this population. Further studies are required to identify directionality and distal correlates for PA and all correlate levels of SB.

Chronic occupational exposure to arsenic induces carcinogenic gene signaling networks and neoplastic transformation in human lung epithelial cells.

Chronic arsenic exposure remains a human health risk; however a clear mode of action to understand gene signaling-driven arsenic carcinogenesis is currently lacking. This study chronically exposed human lung epithelial BEAS-2B cells to low-dose arsenic trioxide to elucidate cancer promoting gene signaling networks associated with arsenic-transformed (B-As) cells. Following a 6month exposure, exposed cells were assessed for enhanced cell proliferation, colony formation, invasion ability and in vivo tumor formation compared to control cell lines. Collected mRNA was subjected to whole genome expression microarray profiling followed by in silico Ingenuity Pathway Analysis (IPA) to identify lung carcinogenesis modes of action. B-As cells displayed significant increases in proliferation, colony formation and invasion ability compared to BEAS-2B cells. B-As injections into nude mice resulted in development of primary and secondary metastatic tumors. Arsenic exposure resulted in widespread up-regulation of genes associated with mitochondrial metabolism and increased reactive oxygen species protection suggesting mitochondrial dysfunction. Carcinogenic initiation via reactive oxygen species and epigenetic mechanisms was further supported by altered DNA repair, histone, and ROS-sensitive signaling. NF-κB, MAPK and NCOR1 signaling disrupted PPARα/δ-mediated lipid homeostasis. A 'pro-cancer' gene signaling network identified increased survival, proliferation, inflammation, metabolism, anti-apoptosis and mobility signaling. IPA-ranked signaling networks identified altered p21, EF1α, Akt, MAPK, and NF-κB signaling networks promoting genetic disorder, altered cell cycle, cancer and changes in nucleic acid and energy metabolism. In conclusion, transformed B-As cells with their whole genome expression profile provide an in vitro arsenic model for future lung cancer signaling research and data for chronic arsenic exposure risk assessment.

Recessions and health: the impact of economic trends on air pollution in California.

OBJECTIVES: I explored the hypothesis that economic activity has a significant impact on exposure to air pollution and ultimately human health. METHODS: I used county-level employment statistics in California (1980-2000), along with major regulatory periods and other controlling factors, to estimate local concentrations of the coefficient of haze, carbon monoxide, and nitrogen dioxide using a mixed regression model approach. RESULTS: The model explained between 33% and 48% of the variability in air pollution levels as estimated by the overall R(2) values. The relationship between employment measures and air pollution was statistically significant, suggesting that air quality improves during economic downturns. Additionally, major air quality regulations played a significant role in reducing air pollution levels over the study period. CONCLUSIONS: This study provides important evidence of a role for the economy in understanding human exposure to environmental pollution. The evidence further suggests that the impact of environmental regulations are likely to be overstated when they occur during recessionary periods, and understated when they play out during periods of economic growth.

Structural equation models in occupational health: an application to exposure modelling.

OBJECTIVES: Many occupational hygiene surveys are designed to collect pollutant monitoring data from multiple locations simultaneously to better reflect the reality of work-related exposure. The exposure model must account for the complexity inherent in this study design, as well as be flexible to extrapolating exposures across an occupational cohort for dose-response modelling and risk assessment. This paper explores the structural equation model (SEM) as a tool to analyse pollutant monitoring data from occupational studies with multiple concurrent sampling across exposure locations. METHODS: This study uses exposure data from a comprehensive assessment of diesel exhaust in the US trucking industry to test the strength of SEMs over more standard analytical approaches such as ordinary least squares (OLS). The exposure data consist of concurrent sampling of elemental carbon from multiple co-located monitors on individual workers, work area and background levels at 36 different trucking terminals across the USA. RESULTS: The SEM is compared with two separate OLS specifications-one that focuses only on predicting personal exposure and excludes data from the additional monitoring sites, and a second that estimates three separate OLS specifications. When compared with the OLS specifications, the SEM provided a better fit to these layered exposure data. The OLS specifications suffered from bias in the coefficients, including downward bias in the work area and background exposure levels and overstatement of the smoking effect. Additionally, many theoretically valid covariates were significant only in the SEM. CONCLUSIONS: This study provides evidence in favour of more widespread use of SEMs in occupational health. SEMs represent a more robust and realistic framework for modelling multiple exposure pathways and have the potential to reduce exposure misclassification bias and strengthen the linkages between studies of exposure and disease outcomes.

Potential air toxics hot spots in truck terminals and cabs.

INTRODUCTION: Hot spots are areas where concentrations of one or more air toxics--organic vapors or particulate matter (PM)--are expected to be elevated. The U.S. Environmental Protection Agency's (EPA*) screening values for air toxics were used in our definition of hot spots. According to the EPA, a screening value "is used to indicate a concentration of a chemical in the air to which a person could be continually exposed for a lifetime ... and which would be unlikely to result in a deleterious effect (either cancer or noncancer health effects)" (U.S. EPA 2006). Our characterization of volatile organic compounds (VOCs; namely 18 hydrocarbons, methyl tert-butyl ether [MTBE], acetone, and aldehydes) was added onto our ongoing National Cancer Institute-funded study of lung cancer and particulate pollutant concentrations (PM with an aerodynamic diameter < or = 2.5 microm [PM2.5], elemental carbon [EC], and organic carbon [OC]) and source apportionment of the U.S. trucking industry. We focused on three possible hot spots within the trucking terminals: upwind background areas affected by nearby industrial parks; downwind areas affected by upwind and terminal sources; and the loading docks and mechanic shops within terminal as well as the interior of cabs of trucks being driven on city, suburban, and rural streets and on highways. METHODS: In Phase 1 of our study, 15 truck terminals across the United States were each visited for five consecutive days. During these site visits, sorbent tubes were used to collect 12-hour integrated samples of hydrocarbons and aldehydes from upwind and downwind fence-line locations as well as inside truck cabs. Meteorologic data and extensive site information were collected with each sample. In Phase 2, repeat visits to six terminals were conducted to test the stability of concentrations across time and judge the representativeness of our previous measurements. During the repeat site visits, the sampling procedure was expanded to include real-time sampling for total hydrocarbon (HC) and PM2.5 at the terminal upwind and downwind sites and inside the truck cabs, two additional monitors in the yard for four-quadrant sampling to better characterize the influence of wind, and indoor sampling in the loading dock and mechanic shop work areas. RESULTS: Mean and median concentrations of VOCs across the sampling locations in and around the truck terminals showed significant variability in the upwind concentrations as well as in the intensity of exposures for drivers, loading-dock workers, and mechanics. The area of highest concentrations varied, although the lowest concentrations were always found in the upwind background samples. However, the downwind samples, which included the terminal's contribution, were on average only modestly higher than the upwind samples. In the truck terminal, the mechanic-shop-area concentrations were consistently elevated for many of the VOCs (including the xylenes, alkanes, and acetone) and particulates; the loading-dock concentrations had relatively high concentrations of 1,3-butadiene, formaldehyde, and acetaldehyde; and nonsmoking driver exposures were elevated for benzene, MTBE, styrene, and hexane. Also, the loading dock and yard background concentrations for EC and PM2.5 were highly correlated with many of the VOCs (50% of pairs tested with Spearman r > 0.5 and 75% with r > 0.4); in the mechanic shop VOCs were correlated with EC but not PM2.5 (r = 0.4-0.9 where significant); and for driver exposures VOC correlations with EC and PM2.5 were relatively low, with the exception of a few aromatics, primarily benzene (r = 0.4-0.5). A principal component analysis of background source characteristics across the terminal locations that had repeat site visits identified three different groupings of variables (the "components"). This analysis suggested that a strong primary factor for hydrocarbons (alkanes and aromatics) was the major contributor to VOC variability in the yard upwind measurement. Aldehydes and acetone, which loaded onto the second and third components, were responsible for a smaller contribution to VOC variability. A multi-layer exposure model was constructed using structural equation modeling techniques that significantly predicted the yard upwind concentrations of individual VOCs as a function of wind speed, road proximity, and regional location (R2 = 0.5-0.9). This predicted value for the yard background concentration was then used to calculate concentrations for the loading dock and mechanic shop. Finally, we conducted a detailed descriptive analysis of the real-time data collected in the yard and in truck cabs during the six repeat site visits, which included more than 50 12-hour sessions at each sampling location. The real-time yard monitoring results suggested that under some conditions there was a clear upwind-to-downwind trend indicating a terminal contribution, which was not apparent in the integrated sampling data alone. They also suggested a nonlinear relationship with wind speed: calm conditions (wind speed < 2 mph) were associated with erratic upwind-downwind differences, lower wind speeds (2 to 10 mph) favored transport with little dilution, and higher wind speeds (> 10 mph) favored dilution and dispersal (more so for VOCs than for PM). Finally, an analysis of the real-time data for driver exposures in trucks with a global positioning system (GPS) matched with geographic information system (GIS) data suggested a clear influence of traffic and industrial sources along a given route with peaks in driver exposures. These peaks were largely associated with traffic, major intersections, idling at the terminals, and pickup and delivery (P&D) periods. However, VOCs and PM2.5 had different exposure patterns: VOCs exposures increased when the vehicle was stopped, and PM2.5 exposures increased during travel in traffic. CONCLUSIONS: All three types of testing sites--upwind and downwind fence-line locations and inside truck cabs while in heavy traffic--met the established definition for a hot spot by having periods with concentrations of pollutants that exceeded the EPA's screening values. Most frequently, the pollutants with concentrations exceeding the screening values were formaldehyde, acetaldehyde, and EC (which serves as a marker for diesel particulate); less frequently they were 1,3-butadiene and benzene. In the case of the downwind location of a single truck terminal without an aggregation of other sources, high concentrations of VOCs and PM were infrequent. Using structural equation modeling, a model was developed that could identify combinations of conditions and factors likely to produce hot spots. Source apportionment analyses showed that EC came predominantly from diesel emissions. As expected from the sites studied, organic vapors associated with vehicle emissions (C6-C8 alkanes and aromatics) were the predominant components of VOCs, followed by formaldehyde and acetaldehyde. For driver exposures, high VOC values were associated with stopped vehicles, and high PM2.5 values were associated with conditions during driving.

Impact of training modes on fitness and body composition in women with obesity: A systematic review and meta-analysis.

OBJECTIVE: This study aimed to assess the effectiveness of different exercise modalities and determine the optimal exercise prescription for improving cardiorespiratory fitness, body composition, and metabolic health of women with obesity. METHODS: A systematic review of randomized controlled trials (RCTs) published between January 1988 and October 2020 was conducted. The RCTs were screened using the following inclusion criteria: 1) participants: women aged 18 to 65 years with BMI > 30 kg/m2 and without comorbidities; 2) intervention: exercise; 3) comparison: non-intervention control; and 4) outcomes measures: cardiorespiratory fitness (maximal oxygen consumption), body composition (i.e., body weight, percentage body fat), and/or metabolic measures (i.e., blood pressure, cholesterol). RESULTS: A total of 20 RCTs with a total of 2,062 participants were included. Although the results showed that any form of exercise was more effective than control, improvements in fitness and body composition were modest. Aerobic exercise (vigorous and moderate intensity) appeared most promising for improving fitness and body weight, whereas low-load resistance training resulted in the largest improvements in body fatness. CONCLUSIONS: In women living with obesity, aerobic exercise was consistently effective in improving fitness and body composition. Although both resistance training and combined exercise interventions appear promising, more research is needed to evaluate their efficacy and determine an optimal exercise prescription for this population.

Comparison of time-matched aerobic, resistance or combined exercise training in women living with obesity: a protocol for a pilot randomised controlled trial-the EXOFFIT (Exercise for Obesity in Females to increase Fitness) study.

INTRODUCTION: Obesity in women has more than doubled in the past thirty years. Increasing research suggests that increased cardiorespiratory fitness (CRF) can largely attenuate the negative health risks associated with obesity. Though previous literature suggests that combined training may be the most effective for improving CRF in adults with obesity, there is minimal research investigating the efficacy of combined and resistance programmes in women with obesity. This article outlines a protocol for a parallel pilot study which aims to evaluate the feasibility and efficacy of three exercise modalities in women with obesity for increasing CRF and strength and improving body composition and other health outcomes (i.e. quality of life). METHODS AND ANALYSIS: Sixty women (aged 18-50) with obesity (body mass index [BMI] ≥ 30 and/or waist circumference ≥ 88 cm) who are physically inactive, have no unstable health conditions and are safe to exercise will be recruited from September 2021 to December 2022. The main outcome will be feasibility and acceptability of the intervention and procedures. Trial feasibility outcomes will be evaluated to determine if a definitive trial should be undertaken. Trial acceptability will be explored through follow-up qualitative interviews with participants. Secondary outcomes will include CRF (predicted VO2 max), anthropometrics (i.e. BMI), strength (5RM bench press, leg dynamometry, grip strength) and other health outcomes (i.e., pain). Participants will be block randomised into one of four trial arms (aerobic exercise, resistance training and combined training groups, non-active control group) and measurements will be completed pre- and post-intervention. The exercise groups will receive an individualised supervised exercise programme for 3× sessions/week for 12 weeks. The change in mean values before and after intervention will be calculated for primary and secondary outcomes. ANOVA and t-tests will be applied to evaluate within-group and between-group differences. If sufficient participants are recruited, the data will be analysed using ANCOVA with the age and BMI as covariates. DISCUSSION: This pilot will provide data on the feasibility and acceptability of trial procedures and of the programmes' three progressive time-matched exercise interventions (aerobic, resistance and combined) for women living with obesity, which will help inform future research and the potential development of a full-scale randomised clinical trial. TRIAL REGISTRATION: ISRCTN, ISRCTN13517067 . Registered 16 November 2021-retrospectively registered.

Westerly drives long-distance transport of radionuclides from nuclear events to glaciers in the Third Pole.

Major nuclear bomb tests and nuclear power plant incidents release large amounts of radionuclides. This study investigates beta (ß) activities of radionuclides from four ice cores in the Third Pole (TP) to understand the transport routes and related atmospheric processes affecting the radionuclides deposition in glaciers of the region. All the ice cores show three major ß activity peaks in the ice layers corresponding to 1963, 1986, and 2011. The ß activity peak in the 1963 ice layer is referred to as the well-known 1962 Nuclear Bomb Test. Beta activity peaks in 1986 and 2011 ice layers from the Chernobyl and Fukushima Nuclear Incidents (CNI, FNI). Hysplit forward and backward trajectory analyses suggest that the radionuclides were transported by the westerly into the stratosphere and then to the high elevation TP glaciers. In the FNI case, the radionuclides traveled over Japan, the Pacific Ocean, Europe, and central Asia before being deposited in the TP glaciers. Investigations of the atmospheric circulation confirm that the stronger northern branch of westerly is responsible for high radionuclides during the FNI in the TP. Less precipitation with water vapor flux component divergence after the FNI also contributed to the enriched radionuclides.

Comparing gravimetric and real-time sampling of PM(2.5) concentrations inside truck cabins.

As part of a study on truck drivers' exposure and health risk, pickup and delivery (P&D) truck drivers' on-road exposure patterns to PM(2.5) were assessed in five, weeklong sampling trips in metropolitan areas of five U.S. cities from April to August of 2006. Drivers were sampled with real-time (DustTrak) and gravimetric samplers to measure average in-cabin PM(2.5) concentrations and to compare their correspondence in moving trucks. In addition, GPS measurements of truck locations, meteorological data, and driver behavioral data were collected throughout the day to determine which factors influence the relationship between real-time and gravimetric samplers. Results indicate that the association between average real-time and gravimetric PM(2.5) measurements on moving trucks was fairly consistent (Spearman rank correlation of 0.63), with DustTrak measurements exceeding gravimetric measurements by approximately a factor of 2. This ratio differed significantly only between the industrial Midwest cities and the other three sampled cities scattered in the South and West. There was also limited evidence of an effect of truck age. Filter samples collected concurrently with DustTrak measurements can be used to calibrate average mass concentration responses for the DustTrak, allowing for real-time measurements to be integrated into longer-term studies of inter-city and intra-urban exposure patterns for truck drivers.

Health Effects of Night and Irregular Shiftwork: A Longitudinal Cohort Study of US Workers.

OBJECTIVES: Evidence suggests that shiftwork results in adverse occupational health outcomes. This paper contributes to the literature by estimating the separate health effects of night and irregular shiftwork on a longitudinal panel of US workers. METHODS: Data from a 20-year panel of worker surveys from the 1979 National Longitudinal Survey of Youth were used to predict self-reported health limitations related to night and irregular shiftwork using a series of random effects logit models. RESULTS: Separate and combined specifications of shiftwork as night and irregular effort significantly increase the odds of health limitations compared with working a regular daytime schedule, with more pronounced effects for irregular work (odds ratio [OR] = 1.09 to 1.52) over night shift (OR = 1.03 to 1.14). CONCLUSIONS: The results suggest that both night and irregular shiftwork may have important negative implications on occupational health, with the deleterious effects particularly pronounced for irregularly scheduled work effort.

Glacier ice archives nearly 15,000-year-old microbes and phages.

BACKGROUND: Glacier ice archives information, including microbiology, that helps reveal paleoclimate histories and predict future climate change. Though glacier-ice microbes are studied using culture or amplicon approaches, more challenging metagenomic approaches, which provide access to functional, genome-resolved information and viruses, are under-utilized, partly due to low biomass and potential contamination. RESULTS: We expand existing clean sampling procedures using controlled artificial ice-core experiments and adapted previously established low-biomass metagenomic approaches to study glacier-ice viruses. Controlled sampling experiments drastically reduced mock contaminants including bacteria, viruses, and free DNA to background levels. Amplicon sequencing from eight depths of two Tibetan Plateau ice cores revealed common glacier-ice lineages including Janthinobacterium, Polaromonas, Herminiimonas, Flavobacterium, Sphingomonas, and Methylobacterium as the dominant genera, while microbial communities were significantly different between two ice cores, associating with different climate conditions during deposition. Separately, ~355- and ~14,400-year-old ice were subject to viral enrichment and low-input quantitative sequencing, yielding genomic sequences for 33 vOTUs. These were virtually all unique to this study, representing 28 novel genera and not a single species shared with 225 environmentally diverse viromes. Further, 42.4% of the vOTUs were identifiable temperate, which is significantly higher than that in gut, soil, and marine viromes, and indicates that temperate phages are possibly favored in glacier-ice environments before being frozen. In silico host predictions linked 18 vOTUs to co-occurring abundant bacteria (Methylobacterium, Sphingomonas, and Janthinobacterium), indicating that these phages infected ice-abundant bacterial groups before being archived. Functional genome annotation revealed four virus-encoded auxiliary metabolic genes, particularly two motility genes suggest viruses potentially facilitate nutrient acquisition for their hosts. Finally, given their possible importance to methane cycling in ice, we focused on Methylobacterium viruses by contextualizing our ice-observed viruses against 123 viromes and prophages extracted from 131 Methylobacterium genomes, revealing that the archived viruses might originate from soil or plants. CONCLUSIONS: Together, these efforts further microbial and viral sampling procedures for glacier ice and provide a first window into viral communities and functions in ancient glacier environments. Such methods and datasets can potentially enable researchers to contextualize new discoveries and begin to incorporate glacier-ice microbes and their viruses relative to past and present climate change in geographically diverse regions globally. Video Abstract.