49 research outputs found
Increasing atmospheric nitrogen deposition: implications for tallgrass prairie restoration
Continued intensification of agriculture and combustion of fossil fuels will increase rates of atmospheric nitrogen (N) deposition over the next century. N is typically a limiting resource for terrestrial plants, and many species are adapted to low-N conditions. Increased N availability can affect both plant biomass and species composition, often favouring N-demanding, adventive species. These effects can be adverse in the context of ecological restoration, where the end product often relies on establishing a particular community composition. I used a field experiment in Norfolk County, Ontario, to examine how N addition affects species composition and plant productivity of a tallgrass prairie restoration. I predicted that N addition would increase the abundance of plant species not included in the original seeding. Contrary to my prediction, relative abundance of native, rather than adventive species, increased with N addition, although the latter species were scarce at the site, possibly as a result of dispersal limitation. I conclude that increased N availability can enhance the growth of tallgrass prairie species in the first few years of restoration
Should a colon cancer screening decision aid include the option of no testing? A comparative trial of two decision aids
<p>Abstract</p> <p>Background</p> <p>An important question in the development of decision aids about colon cancer (CRC) screening is whether to include an explicit discussion of the option of not being screened. We examined the effect of including or not including an explicit discussion of the option of deciding not to be screened in a CRC screening decision aid on subjective measures of decision aid content; interest in screening; and knowledge.</p> <p>Methods</p> <p>Adults ages 50–85 were assigned to view one of two versions of the decision aid. The two versions differed only in the inclusion of video segments of two men, one of whom decided against being screened. Participants completed questionnaires before and after viewing the decision aid to compare subjective measures of content, screening interest and intent, and knowledge between groups. Likert response categories (5-point) were used for subjective measures of content (eg. clarity, balance in favor/against screening, and overall rating), and screening interest. Knowledge was measured with a three item index and individual questions. Higher scores indicated favorable responses for subjective measures, greater interest, and better knowledge. For the subjective balance, lower numbers were associated with the impression of the decision aid favoring CRC screening.</p> <p>Results</p> <p>57 viewed the "with" version which included the two segments and 49 viewed the "without" version. After viewing, participants found the "without" version to have better subjective clarity about benefits of screening ("with" 3.4, "without" 4.1, <it>p </it>< 0.01), and to have greater clarity about downsides of screening ("with" 3.2, "without" 3.6, <it>p </it>= 0.03). The "with" version was considered to be less strongly balanced in favor of screening. ("with" 1.8, "without" 1.6, <it>p </it>= 0.05); but the "without" version received a better overall rating ("with" 3.5, "without" 3.8, <it>p </it>= 0.03). Groups did not differ in screening interest after viewing a decision aid or knowledge.</p> <p>Conclusion</p> <p>A decision aid with the explicit discussion of the option of deciding not to be screened appears to increase the impression that the program was not as strongly in favor of screening, but decreases the impression of clarity and resulted in a lower overall rating. We did not observe clinically important or statistically significant differences in interest in screening or knowledge.</p
The uptake and effect of a mailed multi-modal colon cancer screening intervention: A pilot controlled trial
Abstract Background We sought to determine whether a multi-modal intervention, which included mailing a patient reminder with a colon cancer decision aid to patients and system changes allowing direct access to scheduling screening tests through standing orders, would be an effective and efficient means of promoting colon cancer screening in primary care practice. Methods We conducted a controlled trial comparing the proportion of intervention patients who received colon cancer screening with wait list controls at one practice site. The intervention was a mailed package that included a letter from their primary care physician, a colon cancer screening decision aid, and instructions for obtaining each screening test without an office visit so that patients could access screening tests directly. Major outcomes were screening test completion and cost per additional patient screened. Results In the intervention group, 15% (20/137) were screened versus 4% (4/100) in the control group (difference 11%; (95%; CI 3%;18% p = 0.01). The cost per additional patient screened was estimated to be $94. Conclusion A multi-modal intervention, which included mailing a patient reminder with a colon cancer decision aid to patients and system changes allowing patients direct access to schedule screening tests, increased colon cancer screening test completion in a subset of patients within a single academic practice. Although the uptake of the decision aid was low, the cost was also modest, suggesting that this method could be a viable approach to colon cancer screening
Pathogenicity and immunogenicity of attenuated, nef-deleted HIV-1 strains in vivo
In efforts to develop an effective vaccine, sterilizing immunity to primate lentiviruses has only been achieved by the use of live attenuated viruses carrying major deletions in nef and other accessory genes. Although live attenuated HIV vaccines are unlikely to be developed due to a myriad of safety concerns, opportunities exist to better understand the correlates of immune protection against HIV infection by studying rare cohorts of long-term survivors infected with attenuated, nef-deleted HIV strains such as the Sydney blood bank cohort (SBBC). Here, we review studies of viral evolution, pathogenicity, and immune responses to HIV infection in SBBC members. The studies show that potent, broadly neutralizing anti-HIV antibodies and robust CD8+ T-cell responses to HIV infection were not necessary for long-term control of HIV infection in a subset of SBBC members, and were not sufficient to prevent HIV sequence evolution, augmentation of pathogenicity and eventual progression of HIV infection in another subset. However, a persistent T-helper proliferative response to HIV p24 antigen was associated with long-term control of infection. Together, these results underscore the importance of the host in the eventual outcome of infection. Thus, whilst generating an effective antibody and CD8+ T-cell response are an essential component of vaccines aimed at preventing primary HIV infection, T-helper responses may be important in the generation of an effective therapeutic vaccine aimed at blunting chronic HIV infection
2011 Wild Blueberry Project Reports
The 2011 edition of the Wild Blueberry Project Reports was prepared for the Wild Blueberry Commission of Maine and the Wild Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include:
1. Mechanisms through which wild blueberries affect functional characteristics of the arterial wall related to endothelial dysfunction in Spontaneously Hypertensive Rats
2. Do wild blueberries affect high blood lipids, high blood glucose and obesity as related to the Metabolic Syndrome?
3. Control tactics for blueberry pest insects, 2011
4. IPM strategies, 2011
5. Biology and ecology of pest insects, 2011
6. Biology and ecology of beneficial insects, 2011
7. Pesticide residues on lowbush blueberry, 2011
8. Maine wild blueberry –mummy berry research and extension
9. Valdensinia leaf spot – Education, control and research – 2011
10. Effect of soil pH on nutrient uptake
11. Evaluation of several growth regulators for stimulating lowbush blueberry rhizome production
12. Evaluation of the effects of Gypsum (CaSO4) on wild blueberry fruit Ca concentration
13. Fall application of tribenuron methyl for bunchberry control in wild blueberries, 2009-2011 – effects of fall versus spring pruning on cover and yield in the crop year (final report)
14. Wild Blueberry Extension Education Program in 2011
INPUT SYSTEMS STUDY:
15. Systems approach to improving the sustainability of wild blueberry production, Year 2 of a four-year study – experimental design
16. The effects of different agronomic practices on the composition and quality of wild blueberries
17. Systems approach to improving the sustainability of wild blueberry production, Year 2 of a four-year study, blueberry quality from the first harvest year
18. Food safety- Prevalence study of Escherichia coli O157:H7, Listeria monocytogenes and Salmonella spp. on lowbush blueberries (Vaccinium angustifolium)
19. Abundance of insect pest species and natural enemies in lowbush blueberry fields maintained under different management practices
20. Systems approach to improving the sustainability of wild blueberry production, Year 2 of a four-year study, disease management results
21. Systems approach to improving the sustainability of wild blueberry production, Year 2 of a four-year study, weed management results
22. Systems approach to improving sustainability of wild blueberry production, Year 1 of a four-year study, preliminary soil health and chemistry results
23. Management effects on the phosphorus chemistry of wild blueberry barrens soil
24. Systems approach to improving the sustainability of wild blueberry production, preliminary economic comparison 2010-2011
25. Transition to organic production Year 2: Evaluation of gypsum and bone char
26. The effect of field management, forest edge composition, and field location on insect-mediated ecosystem services (scavenging/predation) (ancillary study)
27. Pre-emergent combinations of herbicides for weed control in wild blueberry fields (ancillary study)
28. Systems approach to improving the sustainability of wild blueberry production – Ancillary land-leveling study, year 1 (ancillary study)
29. Effects of compost and mulch on soil health and soil nutrient dynamics in wild blueberry (ancillary study
Patterns and correlates of tobacco control behavior among american association of pediatric dentistry members: a cross-sectional national study
<p>Abstract</p> <p>Background</p> <p>To determine the tobacco-related knowledge, attitudes, and practice behaviors among US pediatric dentists.</p> <p>Methods</p> <p>A survey was conducted in 1998 among a national, random sample of 1500 American Academy of Pediatric Dentistry members. Chi-square tests and logistic regression with odds ratios (ORs) and 95% confidence intervals assessed factors related to pediatric dentists' tobacco control behaviors.</p> <p>Results</p> <p>Response was 65% for the survey. Only 12% of respondents had prior tobacco prevention/cessation training. Of those untrained, 70% were willing to be trained. Less than two-thirds correctly answered any of four tobacco-related knowledge items. Over one-half agreed pediatric dentists should engage in tobacco control behaviors, but identified patient resistance as a barrier. About 24% of respondents reported always/often asking their adolescent patients about tobacco use; 73% reported always/often advising known tobacco users to quit; and 37% of respondents always/often assisting with stopping tobacco use. Feeling prepared to perform tobacco control behaviors (ORs = 1.9–2.8), a more positive attitude score (4 points) from 11 tobacco-related items (ORs = 1.5–1.8), and a higher statewide tobacco use prevalence significantly predicted performance of tobacco control behaviors.</p> <p>Conclusion</p> <p>Findings suggest thatraining programs on tobacco use and dependence treatment in the pediatric dental setting may be needed to promote tobacco control behaviors for adolescent patients.</p
Global incidence, prevalence, years lived with disability (YLDs), disability-adjusted life-years (DALYs), and healthy life expectancy (HALE) for 371 diseases and injuries in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
Background: Detailed, comprehensive, and timely reporting on population health by underlying causes of disability and premature death is crucial to understanding and responding to complex patterns of disease and injury burden over time and across age groups, sexes, and locations. The availability of disease burden estimates can promote evidence-based interventions that enable public health researchers, policy makers, and other professionals to implement strategies that can mitigate diseases. It can also facilitate more rigorous monitoring of progress towards national and international health targets, such as the Sustainable Development Goals. For three decades, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) has filled that need. A global network of collaborators contributed to the production of GBD 2021 by providing, reviewing, and analysing all available data. GBD estimates are updated routinely with additional data and refined analytical methods. GBD 2021 presents, for the first time, estimates of health loss due to the COVID-19 pandemic. Methods: The GBD 2021 disease and injury burden analysis estimated years lived with disability (YLDs), years of life lost (YLLs), disability-adjusted life-years (DALYs), and healthy life expectancy (HALE) for 371 diseases and injuries using 100 983 data sources. Data were extracted from vital registration systems, verbal autopsies, censuses, household surveys, disease-specific registries, health service contact data, and other sources. YLDs were calculated by multiplying cause-age-sex-location-year-specific prevalence of sequelae by their respective disability weights, for each disease and injury. YLLs were calculated by multiplying cause-age-sex-location-year-specific deaths by the standard life expectancy at the age that death occurred. DALYs were calculated by summing YLDs and YLLs. HALE estimates were produced using YLDs per capita and age-specific mortality rates by location, age, sex, year, and cause. 95% uncertainty intervals (UIs) were generated for all final estimates as the 2·5th and 97·5th percentiles values of 500 draws. Uncertainty was propagated at each step of the estimation process. Counts and age-standardised rates were calculated globally, for seven super-regions, 21 regions, 204 countries and territories (including 21 countries with subnational locations), and 811 subnational locations, from 1990 to 2021. Here we report data for 2010 to 2021 to highlight trends in disease burden over the past decade and through the first 2 years of the COVID-19 pandemic. Findings: Global DALYs increased from 2·63 billion (95% UI 2·44–2·85) in 2010 to 2·88 billion (2·64–3·15) in 2021 for all causes combined. Much of this increase in the number of DALYs was due to population growth and ageing, as indicated by a decrease in global age-standardised all-cause DALY rates of 14·2% (95% UI 10·7–17·3) between 2010 and 2019. Notably, however, this decrease in rates reversed during the first 2 years of the COVID-19 pandemic, with increases in global age-standardised all-cause DALY rates since 2019 of 4·1% (1·8–6·3) in 2020 and 7·2% (4·7–10·0) in 2021. In 2021, COVID-19 was the leading cause of DALYs globally (212·0 million [198·0–234·5] DALYs), followed by ischaemic heart disease (188·3 million [176·7–198·3]), neonatal disorders (186·3 million [162·3–214·9]), and stroke (160·4 million [148·0–171·7]). However, notable health gains were seen among other leading communicable, maternal, neonatal, and nutritional (CMNN) diseases. Globally between 2010 and 2021, the age-standardised DALY rates for HIV/AIDS decreased by 47·8% (43·3–51·7) and for diarrhoeal diseases decreased by 47·0% (39·9–52·9). Non-communicable diseases contributed 1·73 billion (95% UI 1·54–1·94) DALYs in 2021, with a decrease in age-standardised DALY rates since 2010 of 6·4% (95% UI 3·5–9·5). Between 2010 and 2021, among the 25 leading Level 3 causes, age-standardised DALY rates increased most substantially for anxiety disorders (16·7% [14·0–19·8]), depressive disorders (16·4% [11·9–21·3]), and diabetes (14·0% [10·0–17·4]). Age-standardised DALY rates due to injuries decreased globally by 24·0% (20·7–27·2) between 2010 and 2021, although improvements were not uniform across locations, ages, and sexes. Globally, HALE at birth improved slightly, from 61·3 years (58·6–63·6) in 2010 to 62·2 years (59·4–64·7) in 2021. However, despite this overall increase, HALE decreased by 2·2% (1·6–2·9) between 2019 and 2021. Interpretation: Putting the COVID-19 pandemic in the context of a mutually exclusive and collectively exhaustive list of causes of health loss is crucial to understanding its impact and ensuring that health funding and policy address needs at both local and global levels through cost-effective and evidence-based interventions. A global epidemiological transition remains underway. Our findings suggest that prioritising non-communicable disease prevention and treatment policies, as well as strengthening health systems, continues to be crucially important. The progress on reducing the burden of CMNN diseases must not stall; although global trends are improving, the burden of CMNN diseases remains unacceptably high. Evidence-based interventions will help save the lives of young children and mothers and improve the overall health and economic conditions of societies across the world. Governments and multilateral organisations should prioritise pandemic preparedness planning alongside efforts to reduce the burden of diseases and injuries that will strain resources in the coming decades. Funding: Bill & Melinda Gates Foundation
A Giant Dinosaur from the Earliest Jurassic of South Africa and the Transition to Quadrupedality in Early Sauropodomorphs
Sauropod dinosaurs were dominant, bulk-browsing herbivores for 130 million years of the Mesozoic, attaining gigantic body masses in excess of 60 metric tons [1, 2]. A columnar-limbed, quadrupedal posture enabled these giant body sizes [3], but the nature of the transition from bipedal sauropodomorph ancestors to derived quadrupeds remains contentious [4, 5, 6]. We describe a gigantic, new sauropodomorph from the earliest Jurassic of South Africa weighing 12 metric tons and representing a phylogenetically independent origin of sauropod-like body size in a non-sauropod. Osteohistological evidence shows that this specimen was an adult of maximum size and approximately 14 years old at death. Ledumahadi mafube gen. et sp. nov. shows that gigantic body sizes were possible in early sauropodomorphs, which were habitual quadrupeds but lacked the derived, columnar limb postures of sauropods. We use data from this new taxon and a discriminant analysis of tetrapod limb measurements to study postural evolution in sauropodomorphs. Our results show that quadrupedality appeared by the mid-Late Triassic (Norian), well outside of Sauropoda. Secondary reversion to bipedality occurred in some lineages phylogenetically close to Sauropoda, indicating early experimentation in locomotory styles. Morphofunctional observations support the hypothesis that partially flexed (rather than columnar) limbs characterized Ledumahadi and other early-branching quadrupedal sauropodomorphs. Patterns of locomotory and body-size evolution show that quadrupedality allowed Triassic sauropodomorphs to achieve body sizes of at least 3.8 metric tons. Ledumahadi’s Early Jurassic age shows that maximum body mass in sauropodomorph dinosaurs was either unaffected or rapidly rebounded after the end-Triassic extinction event