32 research outputs found
The Cognitive Mediating Process of Diabetes among African-American College Students
Diabetes places a tremendous burden of health inequity on African-American women in the United States. Behavioral risk factors for diabetes underscore the importance of determining to what extent African-American college students are motivated to adhere to protective behaviors that may decrease the likelihood of diabetes onset. The purpose of this study was to evaluate threat and coping appraisal of diabetes among African-American women enrolled in college, using the Protection Motivation Theory (PMT) as a theoretical framework. Questionnaires were administered to 128 African-American women between the ages of 18 and 25 who were enrolled at Florida A & M University, the nation’s largest historically Black university. Bivariate correlations were performed to determine associations involving protection motivation factors (coping and threat appraisals), diabetes knowledge, and demographic characteristics. Statistically significant associations were found between the demographic and knowledge of diabetes variables, and the coping appraisal process. Significant associations were not found with the threat appraisal variables. Furthermore, there was a significant relationship for the maladaptive response of the PMT model between dietary intake levels and perceived severe diabetes threat. For this sample of African-American female students, efforts that articulate active coping strategies may be more effective than those that focus on threat perception. Culturally competent and age appropriate nutrition, physical activity and diabetes education should be increased, given the high percentage of misconceptions about health protection behaviors among study participants. Continuous health education interventions and research focusing on African-American women of college age are needed
An Exploratory Study of the Likelihood of Adopting Genetic Counseling and Testing for Lynch Syndrome-related Colorectal Cancer Among Primary Care Physicians in Florida
Genetic counseling and testing for inherited cancer syndromes have the potential to save lives and may be an avenue for addressing health care disparities among African Americans newly diagnosed with colorectal cancer (CRC); and their close relatives. African Americans are more likely to be diagnosed with CRC at younger ages (under age 50 years), and diagnosed at later stages when cancer is more aggressive and difficult to treat, which are factors associated with hereditary cancers such as Lynch syndrome-related CRC. Considering the benefits of genetic testing for hereditary cancer syndromes - risk stratification, preventive surveillance, targeted treatment, and subsequent reduction in morbidity and mortality among patients by up to 60% - it appears that genetic testing may have a role in prevention, early intervention and reduction of CRC disparities in African Americans. Primary care physicians (PCPs), often the access point to the healthcare system, were anticipated to be at the forefront of genetic counseling and testing. However, a growing body of literature indicates that PCPs see genetic testing as the role of a specialist. This quantitative survey research study, based on the constructs of the Diffusion of Innovation Theory (Rogers, 2003), explored the factors which influence the likelihood of adoption of genetic counseling and testing for Lynch syndrome-related colorectal cancer among PCPs in Florida
Exploring the Association of Physician Characteristics to Patient Requests for Genetic Testing
Background: Cancer genomic testing improves health outcomes for individuals at risk, drives cost-efficiency, and facilitates healthcare equity; however, little is known about how physician demographic and practice characteristics influence patient requests for genetic testing. Purpose: To explore whether (and to what extent) physician demographic and practice characteristics are associated with patient requests for cancer genetic testing. Methods: A cross-sectional quantitative design survey was distributed to 1240 primary care physicians registered with the state health department who had active licenses and main practices in Florida. Primary care physicians were defined as those who practice family medicine, internal medicine, obstetrics, and gynecology. The survey tool was developed from a search of the literature and two previously validated surveys. It was administered using a modified Dillmanstrategy. The study sample size was 317 physicians, with an 85% response rate based upon a targeted sample of 372. Statistical calculations were performed using SPSS version 27 and STATA release 17.Results: Logistic regression model found significant associations between patient requests and physicians\u27 race and professional practice size. Physicians identified as White were 1.840 times as likely to have patient requests for genetic testing (p=.036) than physicians whose race was other than White. Physicians whose professional practices were solo or small groups were 2.39 times as likely to have patient requests (p=.001) than physicians affiliated with larger practices. Discussion: Patient requests may be leveraged by physicians, other healthcare providers, and public health professionals; patient requests present a significant opportunity for increasing genetic testing and thus promoting better health outcomes for patients with Lynch syndrome-related colorectal cancer
Evenness mediates the global relationship between forest productivity and richness
1. Biodiversity is an important component of natural ecosystems, with higher species richness often correlating with an increase in ecosystem productivity. Yet, this relationship varies substantially across environments, typically becoming less pronounced at high levels of species richness. However, species richness alone cannot reflect all important properties of a community, including community evenness, which may mediate the relationship between biodiversity and productivity. If the evenness of a community correlates negatively with richness across forests globally, then a greater number of species may not always increase overall diversity and productivity of the system. Theoretical work and local empirical studies have shown that the effect of evenness on ecosystem functioning may be especially strong at high richness levels, yet the consistency of this remains untested at a global scale. 2. Here, we used a dataset of forests from across the globe, which includes composition, biomass accumulation and net primary productivity, to explore whether productivity correlates with community evenness and richness in a way that evenness appears to buffer the effect of richness. Specifically, we evaluated whether low levels of evenness in speciose communities correlate with the attenuation of the richness–productivity relationship. 3. We found that tree species richness and evenness are negatively correlated across forests globally, with highly speciose forests typically comprising a few dominant and many rare species. Furthermore, we found that the correlation between diversity and productivity changes with evenness: at low richness, uneven communities are more productive, while at high richness, even communities are more productive. 4. Synthesis. Collectively, these results demonstrate that evenness is an integral component of the relationship between biodiversity and productivity, and that the attenuating effect of richness on forest productivity might be partly explained by low evenness in speciose communities. Productivity generally increases with species richness, until reduced evenness limits the overall increases in community diversity. Our research suggests that evenness is a fundamental component of biodiversity–ecosystem function relationships, and is of critical importance for guiding conservation and sustainable ecosystem management decisions
The global biogeography of tree leaf form and habit
Understanding what controls global leaf type variation in trees is crucial for comprehending their role in terrestrial ecosystems, including carbon, water and nutrient dynamics. Yet our understanding of the factors influencing forest leaf types remains incomplete, leaving us uncertain about the global proportions of needle-leaved, broadleaved, evergreen and deciduous trees. To address these gaps, we conducted a global, ground-sourced assessment of forest leaf-type variation by integrating forest inventory data with comprehensive leaf form (broadleaf vs needle-leaf) and habit (evergreen vs deciduous) records. We found that global variation in leaf habit is primarily driven by isothermality and soil characteristics, while leaf form is predominantly driven by temperature. Given these relationships, we estimate that 38% of global tree individuals are needle-leaved evergreen, 29% are broadleaved evergreen, 27% are broadleaved deciduous and 5% are needle-leaved deciduous. The aboveground biomass distribution among these tree types is approximately 21% (126.4 Gt), 54% (335.7 Gt), 22% (136.2 Gt) and 3% (18.7 Gt), respectively. We further project that, depending on future emissions pathways, 17–34% of forested areas will experience climate conditions by the end of the century that currently support a different forest type, highlighting the intensification of climatic stress on existing forests. By quantifying the distribution of tree leaf types and their corresponding biomass, and identifying regions where climate change will exert greatest pressure on current leaf types, our results can help improve predictions of future terrestrial ecosystem functioning and carbon cycling
Evenness mediates the global relationship between forest productivity and richness
1. Biodiversity is an important component of natural ecosystems, with higher species richness often correlating with an increase in ecosystem productivity. Yet, this relationship varies substantially across environments, typically becoming less pronounced at high levels of species richness. However, species richness alone cannot reflect all important properties of a community, including community evenness, which may mediate the relationship between biodiversity and productivity. If the evenness of a community correlates negatively with richness across forests globally, then a greater number of species may not always increase overall diversity and productivity of the system. Theoretical work and local empirical studies have shown that the effect of evenness on ecosystem functioning may be especially strong at high richness levels, yet the consistency of this remains untested at a global scale.
2. Here, we used a dataset of forests from across the globe, which includes composition, biomass accumulation and net primary productivity, to explore whether productivity correlates with community evenness and richness in a way that evenness appears to buffer the effect of richness. Specifically, we evaluated whether low levels of evenness in speciose communities correlate with the attenuation of the richness–productivity relationship.
3. We found that tree species richness and evenness are negatively correlated across forests globally, with highly speciose forests typically comprising a few dominant and many rare species. Furthermore, we found that the correlation between diversity and productivity changes with evenness: at low richness, uneven communities are more productive, while at high richness, even communities are more productive.
4. Synthesis. Collectively, these results demonstrate that evenness is an integral component of the relationship between biodiversity and productivity, and that the attenuating effect of richness on forest productivity might be partly explained by low evenness in speciose communities. Productivity generally increases with species richness, until reduced evenness limits the overall increases in community diversity. Our research suggests that evenness is a fundamental component of biodiversity–ecosystem function relationships, and is of critical importance for guiding conservation and sustainable ecosystem management decisions
Native diversity buffers against severity of non-native tree invasions
Determining the drivers of non-native plant invasions is critical for managing native ecosystems and limiting the spread of invasive species. Tree invasions in particular have been relatively overlooked, even though they have the potential to transform ecosystems and economies. Here, leveraging global tree databases, we explore how the phylogenetic and functional diversity of native tree communities, human pressure and the environment influence the establishment of non-native tree species and the subsequent invasion severity. We find that anthropogenic factors are key to predicting whether a location is invaded, but that invasion severity is underpinned by native diversity, with higher diversity predicting lower invasion severity. Temperature and precipitation emerge as strong predictors of invasion strategy, with non-native species invading successfully when they are similar to the native community in cold or dry extremes. Yet, despite the influence of these ecological forces in determining invasion strategy, we find evidence that these patterns can be obscured by human activity, with lower ecological signal in areas with higher proximity to shipping ports. Our global perspective of non-native tree invasion highlights that human drivers influence non-native tree presence, and that native phylogenetic and functional diversity have a critical role in the establishment and spread of subsequent invasions
The global biogeography of tree leaf form and habit
Understanding what controls global leaf type variation in trees is crucial for comprehending their role in terrestrial ecosystems, including carbon, water and nutrient dynamics. Yet our understanding of the factors influencing forest leaf types remains incomplete, leaving us uncertain about the global proportions of needle-leaved, broadleaved, evergreen and deciduous trees. To address these gaps, we conducted a global, ground-sourced assessment of forest leaf-type variation by integrating forest inventory data with comprehensive leaf form (broadleaf vs needle-leaf) and habit (evergreen vs deciduous) records. We found that global variation in leaf habit is primarily driven by isothermality and soil characteristics, while leaf form is predominantly driven by temperature. Given these relationships, we estimate that 38% of global tree individuals are needle-leaved evergreen, 29% are broadleaved evergreen, 27% are broadleaved deciduous and 5% are needle-leaved deciduous. The aboveground biomass distribution among these tree types is approximately 21% (126.4 Gt), 54% (335.7 Gt), 22% (136.2 Gt) and 3% (18.7 Gt), respectively. We further project that, depending on future emissions pathways, 17-34% of forested areas will experience climate conditions by the end of the century that currently support a different forest type, highlighting the intensification of climatic stress on existing forests. By quantifying the distribution of tree leaf types and their corresponding biomass, and identifying regions where climate change will exert greatest pressure on current leaf types, our results can help improve predictions of future terrestrial ecosystem functioning and carbon cycling
The global biogeography of tree leaf form and habit.
Understanding what controls global leaf type variation in trees is crucial for comprehending their role in terrestrial ecosystems, including carbon, water and nutrient dynamics. Yet our understanding of the factors influencing forest leaf types remains incomplete, leaving us uncertain about the global proportions of needle-leaved, broadleaved, evergreen and deciduous trees. To address these gaps, we conducted a global, ground-sourced assessment of forest leaf-type variation by integrating forest inventory data with comprehensive leaf form (broadleaf vs needle-leaf) and habit (evergreen vs deciduous) records. We found that global variation in leaf habit is primarily driven by isothermality and soil characteristics, while leaf form is predominantly driven by temperature. Given these relationships, we estimate that 38% of global tree individuals are needle-leaved evergreen, 29% are broadleaved evergreen, 27% are broadleaved deciduous and 5% are needle-leaved deciduous. The aboveground biomass distribution among these tree types is approximately 21% (126.4 Gt), 54% (335.7 Gt), 22% (136.2 Gt) and 3% (18.7 Gt), respectively. We further project that, depending on future emissions pathways, 17-34% of forested areas will experience climate conditions by the end of the century that currently support a different forest type, highlighting the intensification of climatic stress on existing forests. By quantifying the distribution of tree leaf types and their corresponding biomass, and identifying regions where climate change will exert greatest pressure on current leaf types, our results can help improve predictions of future terrestrial ecosystem functioning and carbon cycling