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PURPOSE: We sought to distinguish roles of demographic variables and bowel segments as predictors of delayed versus early stage colorectal cancer in California. METHODS: Demographic and anatomic variables for 66,806 colorectal cancers were extracted from the California Cancer Registry for 2004-2008 and analyzed using logistic regression as delayed versus early stage. RESULTS: Odds ratios (OR) for binary stage categories comparing age <40 (OR=2.58; 95% CI=2.26-2.94), 40-49 (1.71; 95%=1.60-1.83) and 75+ (1.05; 1.02-1.09) relative to 50-74 years were computed. Compared with non-Hispanic whites, ORs for stage categories were: 1.05; 0.99-1.13 (non-Hispanic blacks), 1.08; 1.02-1.13 (Hispanics), and 1.05; 1.00-1.10 (Asian/others). Females had higher odds of delayed diagnosis (1.09; 1.06-1.13) than males. Descending ORs were measured for successively lower to highest socioeconomic status (SES) quintiles (OR 4:5=1.08; 1.03-1.14, OR 3:5=1.13; 1.08-1.19, OR 2:5=1.18; 1.12- 1.24, and OR 1:5=1.21; 1.14-1.28). CONCLUSIONS: Younger and older than age 50-74; females; Hispanic ethnicity; bowel segment contrasts (right/left, proximal/distal, cecum plus appendix/distal), and lower SES were independent predictors of delayed diagnosis. Low SES was the most robust predictor of delayed diagnosis, independent of other covariates. Approximately 77% of delayed diagnoses were in non-Hispanic whites and Asian/others. These findings illustrate the value of a community SES index for targeting egalitarian colorectal cancer screening. [ABSTRACT FROM AUTHOR]

INTRODUCTION/PURPOSE: This study compared oxidative stress levels and antioxidant capacity in nonobese and obese participants after acute resistance (RX) and aerobic exercise (AX). METHODS: Blood samples were collected from 28 nonobese (mean = 20.8% body fat) and obese (mean = 35.0% body fat) participants pre- and immediately post-RX and AX. Lipid hydroperoxides (PEROX), malondialdehyde (TBARS) and total antioxidant status (TAS) were measured. Oxygen consumption (VO2) and minute ventilation (VE) values were determined during each exercise session. RESULTS: In both groups, PEROX and TBARS were elevated post-RX and AX, with the greater elevations occurring in the obese group in each case (P < 0.05). In the obese, TBARS increased by 42% and 41% post-RX and AX, respectively, compared with 7.1% and 26.9% in the nonobese group. PEROX increased by 100% and 70% post-RX and AX, respectively, in the obese, and by 85% and 62% in the nonobese. TAS was 17% higher (P < 0.05) post-RX in the nonobese compared with the obese, whereas TAS values were not different post-AX. Peak and average VE, and relative VO2). rates were higher in the obese post-AX compared with the nonobese (P < 0.05) Correlations existed between the exercise-induced change in PEROX and body fat, vitamin C and A intake, peak oxygen consumption, and exercise ventilation rates in the obese group (r = 0.784-0.776, P < 0.05). In both groups, the exercise-induced changes in PEROX were associated with vitamin C intake, exercise ventilation rates, VO2peak, and plasma triglycerides (r = 0.669-0.558, P < 0.05). CONCLUSION: Lipid peroxidation is elevated in both RX and AX, and it is exacerbated in the obese. The mechanisms underlying this response in each exercise may be different but could involve plasma triglycerides, oxygen consumption, and antioxidant intake. [ABSTRACT FROM AUTHOR]

Global change is associated with variable shifts in the annual production of aboveground plant biomass, suggesting localized sensitivities with unclear causal origins. Combining remotely sensed normalized difference vegetation index data since the 1980s with contemporary field data from 84 grasslands on 6 continents, we show a widening divergence in site-level biomass ranging from +51% to -34% globally. Biomass generally increased in warmer, wetter and species-rich sites with longer growing seasons and declined in species-poor arid areas. Phenological changes were widespread, revealing substantive transitions in grassland seasonal cycling. Grazing, nitrogen deposition and plant invasion were prevalent in some regions but did not predict overall trends. Grasslands are undergoing sizable changes in production, with implications for food security, biodiversity and carbon storage especially in arid regions where declines are accelerating., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Local adaptation may facilitate range expansion during invasions, but the mechanisms promoting destructive invasions remain unclear. Cheatgrass ( Bromus tectorum ), native to Eurasia and Africa, has invaded globally, with particularly severe impacts in western North America. We sequenced 307 genotypes and conducted controlled experiments. We found that diverse lineages invaded North America, where long-distance gene flow is common. Ancestry and phenotypic clines in the native range predicted those in the invaded range, indicating pre-adapted genotypes colonized different regions. Common gardens showed directional selection on flowering time that reversed between warm and cold sites, potentially maintaining clines. In the Great Basin, genomic predictions of strong local adaptation identified sites where cheatgrass is most dominant. Preventing new introductions that may fuel adaptation is critical for managing ongoing invasions., Competing Interests: Competing interests: Authors declare that they have no competing interests.

Thermal regimes of aquatic ecosystems are predicted to change as climate warming progresses over the next century, with high-latitude and high-elevation regions predicted to be particularly impacted. Here, we have modelled alpine stream water temperatures from air temperature data and used future predicted air temperature trajectories (representative concentration pathway [rcp] 4.5 and 8.5) to predict future water temperatures. Modelled stream water temperatures have been used to calculate cumulative degree days (CDDs) under current and future climate conditions. These calculations show that degree days will accumulate more rapidly under the future climate scenarios, and with a stronger effect for higher CDD values (e.g., rcp 4.5: 18-28 days earlier [CDD = 500]; 42-55 days earlier [CDD = 2000]). Changes to the time to achieve specific CDDs may have profound and unexpected consequences for alpine ecosystems. Our calculations show that while the effect of increased CDDs may be relatively small for organisms that emerge in spring-summer, the effects for organisms emerging in late summer-autumn may be substantial. For these organisms, the air temperatures experienced upon emergence could reach 9°C (rcp 4.5) or 12°C (rcp 8.5) higher than under current climate conditions, likely impacting on the metabolism of adults, the availability of resources, including food and suitable oviposition habitat, and reproductive success. Given that the movement of aquatic fauna to the terrestrial environment represents an important flux of energy and nutrients, differential changes in the time periods to achieve CDDs for aquatic and terrestrial fauna may de-couple existing predator-prey interactions., (Global Change Biology© 2024 The Author(s). Global Change Biology published by John Wiley & Sons Ltd.)

Background: While telehealth's presence in post-pandemic primary care appears assured, its exact role remains unknown. Value-based care's expansion has heightened interest in telehealth's potential to improve uptake of preventive and chronic disease care, especially among high-risk primary care populations. Despite this, the pandemic underscored patients' diverse preferences around using telehealth. Understanding the factors underlying this population's preferences can inform future telehealth strategies., Objective: To describe the factors informing high-risk primary care patient choice of whether to pursue primary care via telehealth, in-office or to defer care altogether., Design: Qualitative, cross-sectional study utilizing semi-structured telephone interviews of a convenience sample of 29 primary care patients between July 13 and September 30, 2020., Participants: Primary care patients at high risk of poor health outcomes and/or acute care utilization who were offered a follow-up primary care visit via audiovisual, audio-only or in-office modalities., Approach: Responses were analyzed via grounded theory, using a constant comparison method to refine emerging categories, distinguish codes, and synthesize evolving themes., Key Results: Of the 29 participants, 16 (55.2%) were female and 19 (65.5%) were Black; the mean age (SD) was 64.6 (11.1). Participants identified four themes influencing their choice of visit type: perceived utility (encapsulating clinical and non-clinical utility), underlying costs (in terms of time, money, effort, and safety), modifiers (e.g., participants' clinical situation, choice availability, decision phenotype), and drivers (inclusive of their background experiences and digital environment). The relationship of these themes is depicted in a novel framework of patient choice around telehealth use., Conclusions: While visit utility and cost considerations are foundational to participants' decisions around whether to pursue care via telehealth, underappreciated modifiers and drivers often magnify or mitigate these considerations. Policymakers, payers, and health systems can leverage these factors to anticipate and enhance equitable high-value telehealth use in primary care settings among high-risk individuals., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Grassy ecosystems cover ~40% of the global land surface and are an integral component of the global carbon (C) cycle. Grass litter decomposes via a combination of photodegradation (which returns C to the atmosphere rapidly) and biological decomposition (a slower C pathway). As such, decomposition and C storage in grasslands may vary with climate and exposure to solar radiation. We investigated rates of grass litter decomposition in Australian temperate grasslands along a climate gradient to uncouple the relative importance of photodegradation and climate on decomposition. Litterbags containing leaf litter from two common native grass species ( Poa labillardierei , Themeda triandra ) were deployed at six grassland sites across a precipitation gradient (380-890 mm) in south-eastern Australia. Bags were retrieved over 39 weeks to measure mass loss from decomposition. We used shade treatments on the litter of one species ( T. triandra ) to partition photodegradation from biological decomposition. The shade treatment reduced the rate of decomposition of T. triandra relative to the full-sun treatment at all sites, by an average of 38% at 39 weeks; the effect size of the shade treatment was not correlated with site productivity. The rate of decomposition in both species was positively correlated with rainfall midway through the experiment, but there were no significant differences in total decomposition among sites after 39 weeks. By week 39, total decomposition of T. triandra was significantly greater than for P. labillardierei . In general, we observed relatively linear decomposition rather than the strong negative exponential decay observed in many global litter decomposition studies. Synthesis : We found that solar radiation exposure was a strong contributor to litter decomposition in temperate Australian grasslands across a broad climate gradient, which may be related to a period of photopriming prior to further biotic decomposition. This study highlights the importance of litter composition and solar radiation exposure in our understanding of how decomposition patterns contribute to global C cycling., (© 2023 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Understanding the influence of non-native herbivores on ecosystems by means of dietary foraging and seed dispersal is important for understanding how non-native species can alter an invaded landscape, yet requires multiple methodologies. In south-eastern Australia, introduced sambar deer ( Rusa unicolor ) are rapidly expanding in range and placing native ecosystems at risk through browsing and as vectors for seed dispersal. We simultaneously investigated sambar deer dietary composition and seed dispersal using DNA sequencing and germination trials, from faecal pellets collected in alpine and wet forest ecosystems. This allowed us to contrast the dietary impacts of introduced sambar deer in different environments, and to explore the potential for habitat-specific variation in diet. DNA sequencing of the trnL , ITS2 and rbcL gene regions revealed a diverse plant species dietary composition comprising 1003 operational taxonomic units (OTUs). Sambar deer exhibited intermediate feeder behaviours dominated by forbs in alpine and shrubs in wet forest ecosystems. A large proportion of plant OTUs were considered likely to be native, however, the proportion of exotic species in the diet in both ecosystems was greater than would be expected based on the proportion of exotic species in each of the two landscapes. Seed germination trials indicated that sambar deer can disperse a substantial number of native and exotic species in both alpine and wet forest ecosystems. In alpine ecosystems, an individual sambar deer was estimated to disperse on average 816 (±193) seeds per day during the study period, of which 652 (±176) were exotic. Synthesis and applications . Our results suggest that native plant species comprise the majority of sambar deer diets in Australian ecosystems and that the introduced species is dispersing both native and exotic plant species via endozoochory. However, exotic species seedling germination numbers were significantly higher in alpine ecosystems, and given the large daily movements of sambar deer, represents a significant vector for the spread of exotic plant species. Management of native plant species and vegetation communities of conservation significance, or at risk to sambar deer browsing is of high priority, through either the removal of sambar deer or implementation of exclusion-based methods., Competing Interests: The authors declare no conflicts of interest., (© 2023 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Eutrophication usually impacts grassland biodiversity, community composition, and biomass production, but its impact on the stability of these community aspects is unclear. One challenge is that stability has many facets that can be tightly correlated (low dimensionality) or highly disparate (high dimensionality). Using standardized experiments in 55 grassland sites from a globally distributed experiment (NutNet), we quantify the effects of nutrient addition on five facets of stability (temporal invariability, resistance during dry and wet growing seasons, recovery after dry and wet growing seasons), measured on three community aspects (aboveground biomass, community composition, and species richness). Nutrient addition reduces the temporal invariability and resistance of species richness and community composition during dry and wet growing seasons, but does not affect those of biomass. Different stability measures are largely uncorrelated under both ambient and eutrophic conditions, indicating consistently high dimensionality. Harnessing the dimensionality of ecological stability provides insights for predicting grassland responses to global environmental change., (© 2023. Springer Nature Limited.)

Awareness of the presence and significance of disparities in American health outcomes is growing. Equitable access to appropriate medication-pharmacoequity-is foundational to equitable health care, with medication formularies representing a key determinant of medication access. Critical formulary design elements include clinical criteria, prescription processes, and patient access policies. Facets of each can be refined to ensure more equitable access to medications, including avoidance of prior authorization requirements, awareness of the complex determinants of human behavior, streamlined authorization processes, and optimized costs and convenience for patients. Optimizing these factors for proven treatments of conditions disproportionately borne by vulnerable communities is especially critical in the pursuit of equitable access. For policy makers at payer and pharmacy benefit manager organizations to successfully pursue corresponding changes in formulary policy, it is critical that teams educate leadership regarding the importance of policy change, invest in comprehensive patient data, and engage community members in their efforts.

In South Africa, there are a limited number of population estimates of the prevalence of diabetes and its association with psychosocial factors. This study investigates the prevalence of diabetes and its psychosocial correlates in both the general South African population and the Black South African subpopulation using data from the SANHANES-1. Diabetes was defined as a hemoglobin A1c (HbA1c) ≥6.5% or currently on diabetes treatment. Multivariate ordinary least squares and logistic regression models were used to determine factors associated with HbA1c and diabetes, respectively. The prevalence of diabetes was significantly higher among participants who identified as Indian, followed by White and Coloured people, and lowest among Black South Africans. General population models indicated that being Indian, older aged, having a family history of diabetes, and being overweight and obese were associated with HbA1c and diabetes, and crowding was inversely associated with HbA1c and diabetes. HbA1c was inversely associated with being White, having higher education, and residing in areas with higher levels of neighborhood crime and alcohol use. Diabetes was positively associated with psychological distress. The study highlights the importance of addressing the risk factors of psychological distress, as well as traditional risk factors and social determinants of diabetes, in the prevention and control of diabetes at individual and population levels.

Causal effects of biodiversity on ecosystem functions can be estimated using experimental or observational designs - designs that pose a tradeoff between drawing credible causal inferences from correlations and drawing generalizable inferences. Here, we develop a design that reduces this tradeoff and revisits the question of how plant species diversity affects productivity. Our design leverages longitudinal data from 43 grasslands in 11 countries and approaches borrowed from fields outside of ecology to draw causal inferences from observational data. Contrary to many prior studies, we estimate that increases in plot-level species richness caused productivity to decline: a 10% increase in richness decreased productivity by 2.4%, 95% CI [-4.1, -0.74]. This contradiction stems from two sources. First, prior observational studies incompletely control for confounding factors. Second, most experiments plant fewer rare and non-native species than exist in nature. Although increases in native, dominant species increased productivity, increases in rare and non-native species decreased productivity, making the average effect negative in our study. By reducing the tradeoff between experimental and observational designs, our study demonstrates how observational studies can complement prior ecological experiments and inform future ones., (© 2023. The Author(s).)

High-elevation ecosystems are among the few ecosystems worldwide that are not yet heavily invaded by non-native plants. This is expected to change as species expand their range limits upwards to fill their climatic niches and respond to ongoing anthropogenic disturbances. Yet, whether and how quickly these changes are happening has only been assessed in a few isolated cases. Starting in 2007, we conducted repeated surveys of non-native plant distributions along mountain roads in 11 regions from 5 continents. We show that over a 5- to 10-year period, the number of non-native species increased on average by approximately 16% per decade across regions. The direction and magnitude of upper range limit shifts depended on elevation across all regions. Supported by a null-model approach accounting for range changes expected by chance alone, we found greater than expected upward shifts at lower/mid elevations in at least seven regions. After accounting for elevation dependence, significant average upward shifts were detected in a further three regions (revealing evidence for upward shifts in 10 of 11 regions). Together, our results show that mountain environments are becoming increasingly exposed to biological invasions, emphasizing the need to monitor and prevent potential biosecurity issues emerging in high-elevation ecosystems., (© 2023. The Author(s).)

Livestock grazing is an important management tool for biodiversity conservation in many native grasslands across the globe. Understanding how different grazing species interact with their environment is integral to achieving conservation goals. In the semiarid grasslands of Australia, grazing by sheep or cattle is used to manipulate vegetation structure to suit the habitat needs of a globally unique, critically endangered grassland bird, the plains-wanderer Pedionomus torquatus. However, there has been no investigation of whether sheep and cattle differ in their effects on plains-wanderer habitat and, therefore, it is unknown if these grazers are substitutable as a management tool. Using a grazing experiment in native grasslands over 3 years, we determined the effects of grazer type (sheep, cattle) on occurrence and vocal activity of plains-wanderer, vegetation structure and composition, and food availability. We also examined grazer effects on encounter rates of other grassland birds. Plains-wanderer breeding activity was inferred from vocalization rates captured by bioacoustic recorders. Spotlighting was used to measure encounter rates of other grassland birds. We found that different grazers altered the structure of the habitat. Grasslands grazed by cattle were typically more open, less variable, and lacked patches of dense vegetation relative to those grazed by sheep. Grazer type did not influence the likelihood of plains-wanderer occurrence, but it did interact with year of survey to affect breeding activity. The number of days with one or more calls significantly increased at sheep grazed sites in year-3, which coincided with enduring drought conditions. Similarly, grazer effects on encounter rate of all birds, bird species richness, and Australasian pipit Anthus novaeseelandiae were different between years. Dense vegetation specialists (such as stubble quail Coturnix pectoralis) were positively associated with grasslands grazed by sheep. As a habitat management tool, sheep or cattle grazing are useful when the goal is to support an open grassland structure for the plains-wanderer. However, their substitutability is likely to be dependent upon climate. We caution that a loss of dense vegetation in grasslands grazed by cattle during drought could limit the availability of optimal habitat for the plains-wanderer and habitat for other grassland birds., (© 2022 The Ecological Society of America.)

We sought to understand the role that water availability (expressed as an aridity index) plays in determining regional and global patterns of richness and evenness, and in turn how these water availability-diversity relationships may result in different richness-evenness relationships at regional and global scales. We examined relationships between water availability, richness and evenness for eight grassy biomes spanning broad water availability gradients on five continents. Our study found that relationships between richness and water availability switched from positive for drier (South Africa, Tibet and USA) vs. negative for wetter (India) biomes, though were not significant for the remaining biomes. In contrast, only the India biome showed a significant relationship between water availability and evenness, which was negative. Globally, the richness-water availability relationship was hump-shaped, however, not significant for evenness. At the regional scale, a positive richness-evenness relationship was found for grassy biomes in India and Inner Mongolia, China. In contrast, this relationship was weakly concave-up globally. These results suggest that different, independent factors are determining patterns of species richness and evenness in grassy biomes, resulting in differing richness-evenness relationships at regional and global scales. As a consequence, richness and evenness may respond very differently across spatial gradients to anthropogenic changes, such as climate change., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: South Africa has long endured a high prevalence of mental disorders at the national level, and its unique social and historical context could be a contributor to an increased risk of mental health problems. Our current understanding is limited regarding the relative importance of various social determinants to mental health challenges in South Africa, and how existing racial inequities may be explained by these determinants., Methods: This study attempted to elucidate potential social determinants of mental health in South Africa using data from the nationally representative South African National Health and Nutrition Examination Survey (SANHANES-1). The main outcome of interest was psychological distress, measured with the Kessler-10 scale. Hierarchical linear regression models included covariates for demographic and socioeconomic factors, count of traumatic events, and a series of stress-related constructs. Analyses were conducted on two populations: the entire sample (n = 15,981), and the African subpopulation (n = 10,723)., Results: Regression models on the entire sample indicated racial disparities in psychological distress, with Africans experiencing higher distress than White and Coloured individuals. Results within the African sub-population indicated geo-spatial disparities, with Africans in formal urban settings experiencing higher psychological distress than those living in formal and informal rural locales. Across both samples, results indicated a cumulative association between count of stressors and traumatic events and distress., Conclusion: We found racial disparities across several mental health-related domains. Africans had greater exposure to traumatic events, social stressors, and psychological distress. This research is a necessary foundation for public health interventions and policy change to effectively reduce inequities in psychological distress., (© 2021. Springer-Verlag GmbH Germany, part of Springer Nature.)

Nutrients and herbivores are well-known drivers of grassland diversity and stability in local communities. However, whether they interact to impact the stability of aboveground biomass and whether these effects depend on spatial scales remain unknown. It is also unclear whether nutrients and herbivores impact stability via different facets of plant diversity including species richness, evenness, and changes in community composition through time and space. We used a replicated experiment adding nutrients and excluding herbivores for 5 years in 34 global grasslands to explore these questions. We found that both nutrient addition and herbivore exclusion alone reduced stability at the larger spatial scale (aggregated local communities; gamma stability), but through different pathways. Nutrient addition reduced gamma stability primarily by increasing changes in local community composition over time, which was mainly driven by species replacement. Herbivore exclusion reduced gamma stability primarily by decreasing asynchronous dynamics among local communities (spatial asynchrony). Their interaction weakly increased gamma stability by increasing spatial asynchrony. Our findings indicate that disentangling the processes operating at different spatial scales may improve conservation and management aiming at maintaining the ability of ecosystems to reliably provide functions and services for humanity., (© 2022 John Wiley & Sons Ltd.)

Field transplant experiments can improve our understanding of the effects of climate on distributions of plants versus a milieu of biotic factors which may be mediated by climate. We use a transplant experiment to test how survival and growth of a mountain-top daisy ( Podolepis robusta ), when planted within and outside its current local range, varies as a function of individual plant size, elevation, aspect and the presence of other vegetation. We expected a home-site advantage for the species, with highest survival and growth within the species' current elevational limits, and a decline in vital rates above (due to physiological limitations) and below (due to competition with near-neighbours) these limits. Transplant survival during the beginning of the census was high (89 %), though by the third growing season, 36 % of initial transplants were remaining. Elevation had a significant negative effect on individual mortality rates; plants growing at higher elevations had a lower estimated hazard rate and thus, higher survival relative to those planted at elevations below the current lower limit of the distribution. By contrast, we detected no significant effect of elevation on growth rates. Small vegetation gaps had no effect on growth rates, though we found a negative, but non-significant, effect on mortality rates. Aspect had a very strong impact on growth. Plants transplanted to cool aspects had a significantly lower growth rate relative to transplants growing on a warm aspect. Conversely, aspect was not a significant predictor of individual mortality rates. Restrictions on the local distribution of P. robusta appear to be governed by mortality drivers at lower elevation and by growth drivers associated with aspect. We highlight that our ability to understand the drivers of distributions in current and future climates will be limited if contextual- and individual-level plant responses remain understudied., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Annals of Botany Company.)