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1.
Nature ; 621(7977): 112-119, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37648850

RESUMEN

Several coastal ecosystems-most notably mangroves and tidal marshes-exhibit biogenic feedbacks that are facilitating adjustment to relative sea-level rise (RSLR), including the sequestration of carbon and the trapping of mineral sediment1. The stability of reef-top habitats under RSLR is similarly linked to reef-derived sediment accumulation and the vertical accretion of protective coral reefs2. The persistence of these ecosystems under high rates of RSLR is contested3. Here we show that the probability of vertical adjustment to RSLR inferred from palaeo-stratigraphic observations aligns with contemporary in situ survey measurements. A deficit between tidal marsh and mangrove adjustment and RSLR is likely at 4 mm yr-1 and highly likely at 7 mm yr-1 of RSLR. As rates of RSLR exceed 7 mm yr-1, the probability that reef islands destabilize through increased shoreline erosion and wave over-topping increases. Increased global warming from 1.5 °C to 2.0 °C would double the area of mapped tidal marsh exposed to 4 mm yr-1 of RSLR by between 2080 and 2100. With 3 °C of warming, nearly all the world's mangrove forests and coral reef islands and almost 40% of mapped tidal marshes are estimated to be exposed to RSLR of at least 7 mm yr-1. Meeting the Paris agreement targets would minimize disruption to coastal ecosystems.


Asunto(s)
Calentamiento Global , Temperatura , Humedales , Avicennia/fisiología , Secuestro de Carbono , Arrecifes de Coral , Calentamiento Global/prevención & control , Calentamiento Global/estadística & datos numéricos , Animales
2.
J Cancer Educ ; 34(5): 1000-1009, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30062619

RESUMEN

For those diagnosed with cancer, lifestyle factors including diet can be more important than ever. However, lack of nutrition-related knowledge can pose a significant barrier to healthy eating. Food labels guide consumers in selecting appropriate portion sizes-that is, caloric content-and ensuring adequate intake of nutrients. Data from the 2013-2014 HINTS were used to examine (a) differences in food label use and food label literacy between respondents ever had a cancer diagnosis and those never had a diagnosis; (b) sociodemographic correlates and health-related correlates of food label use and literacy, in a context of cancer diagnosis; and (c) potential association between food label use/literacy and each of two dietary choices, eating vegetables and fruits and limiting intake of sugary drinks, again, in a context of cancer diagnosis. Data was analyzed via SPSS version 24.0, and cross tabulations using Pearson's Chi-square test and logistic regressions. Income, gender and non-participation in support groups were associated with food label literacy (p<.05). Confidence to take care of self was associated with food label use (p<.05). Relationships were observed between using food labels and curtailing soda intake (b = -.368, p<.05), eating relatively more fruits (b = .558, p<.05), and eating relatively more vegetables (b = .558, p<.05). The overall models predicting consumption of soda [x2 (2) = 13.70, p = .001, Nagelkerke R-square = .059], of fruits [x2 (2) = 33.87, p < .001, Nagelkerke R-square = .136], and of vegetables [x2 (2) = 36.08, p < .001, Nagelkerke R-square = .144] was statistically significant. Implications for research and practice can be found in results linking food label use to better quality diets. They include the usefulness of nutrition education interventions targeting lower-income men with cancer diagnoses; one lesson should be the use of food labels.


Asunto(s)
Dieta Saludable/psicología , Dieta/normas , Etiquetado de Alimentos/estadística & datos numéricos , Conductas Relacionadas con la Salud , Conocimientos, Actitudes y Práctica en Salud , Alfabetización en Salud/estadística & datos numéricos , Neoplasias/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Conducta Alimentaria , Femenino , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Neoplasias/dietoterapia , Neoplasias/psicología , Encuestas y Cuestionarios , Adulto Joven
3.
Sci Total Environ ; 912: 168955, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38056642

RESUMEN

Mangrove ecosystems are an important blue carbon store but exhibit considerable variation in soil carbon stocks globally. Unravelling the conditions controlling carbon stock is critical for assessing current and future carbon budgets. Mangrove soil biogeochemical cycles can strongly influence carbon storage capacities. We thus investigated carbon sequestration and the environmental parameters shaping variability in biogeochemical cycling and carbon storage in sediment samples from four mangrove sites along an estuarine-to-marine gradient in Hong Kong, a megacity. Our results showed that organic matter in Hong Kong mangroves is sourced principally from autochthonous mangrove plants. Total nitrogen was higher in the freshwater-influenced sites and supplied from different sources. Marine-influenced sites had larger sulfur fractionations, reflecting higher marine-sourced sulfate concentrations and indicating a relatively open sulfate system. We estimated an average organic carbon stock of 115 ± 8 Mg C ha-1 in the upper 100 cm soil layer placing Hong Kong mangroves at the lower end of the global spectrum of the soil carbon stock. Carbon accumulation was found to be driven by a combination of higher total organic matter inputs, soil fluxes, and porosity. Notably, despite having the highest mass-specific soil organic carbon contents, Mai Po had the lowest integrated soil organic carbon storage (77 ± 3 Mg C ha-1). This was primarily due to lower sediment density and higher tidal pumping leading to a decrease in carbon retention. Total organic matter input, sediment characteristics, and hydrodynamics were the main factors influencing soil organic carbon storage. Overall, our results suggest that (1) while multiple parameters can enhance soil organic carbon content and increase carbon storage capacities, (2) hydrodynamics and sediment characteristics can increase the potential for leakage of carbon, and (3) high carbon content does not always equal high carbon sequestration and stock.

4.
Science ; 377(6605): 523-527, 2022 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-35901146

RESUMEN

Much uncertainty exists about the vulnerability of valuable tidal marsh ecosystems to relative sea level rise. Previous assessments of resilience to sea level rise, to which marshes can adjust by sediment accretion and elevation gain, revealed contrasting results, depending on contemporary or Holocene geological data. By analyzing globally distributed contemporary data, we found that marsh sediment accretion increases in parity with sea level rise, seemingly confirming previously claimed marsh resilience. However, subsidence of the substrate shows a nonlinear increase with accretion. As a result, marsh elevation gain is constrained in relation to sea level rise, and deficits emerge that are consistent with Holocene observations of tidal marsh vulnerability.


Asunto(s)
Elevación del Nivel del Mar , Humedales , Incertidumbre
5.
Nat Commun ; 12(1): 1841, 2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33758184

RESUMEN

Sea-level budgets account for the contributions of processes driving sea-level change, but are predominantly focused on global-mean sea level and limited to the 20th and 21st centuries. Here we estimate site-specific sea-level budgets along the U.S. Atlantic coast during the Common Era (0-2000 CE) by separating relative sea-level (RSL) records into process-related signals on different spatial scales. Regional-scale, temporally linear processes driven by glacial isostatic adjustment dominate RSL change and exhibit a spatial gradient, with fastest rates of rise in southern New Jersey (1.6 ± 0.02 mm yr-1). Regional and local, temporally non-linear processes, such as ocean/atmosphere dynamics and groundwater withdrawal, contributed between -0.3 and 0.4 mm yr-1 over centennial timescales. The most significant change in the budgets is the increasing influence of the common global signal due to ice melt and thermal expansion since 1800 CE, which became a dominant contributor to RSL with a 20th century rate of 1.3 ± 0.1 mm yr-1.

6.
J Family Med Prim Care ; 10(12): 4438-4445, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35280639

RESUMEN

Background: Breast Carcinoma (BCa) is the leading cause of cancer among females in Trinidad and Tobago (TnT). This twin-island has a diversified population of 1.3 million individuals that display and are exposed to a variety of lifestyle choices that have been linked to the development of BCa. Therefore, this study aimed to identify the risk factors that influence the development of BCa, analyze the common histopathological details, and categorize BCa based on receptor study. Methods: Cancer information for 120 BCa cases at Eric Williams Medical Sciences Complex from 2012 to 2019 was retrieved, analyzed, and statistically estimated. The clinical details were categorized based on data tabulations, and histological assessment was performed to identify specific features. The receptor analysis was classified based on estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor-2 (HER-2neu) staining intensity. A descriptive data analysis and comparison were statistically evaluated in all these cases. Results: Epidemiological factors influencing the development of BCa were age with a peak of 56-65 years 27.5% (n = 33), ethnicity predominated in Indo-Trinidadians 48.33% (n = 58), and marital status primarily in unmarried/single/widowed patients 55% (n = 66). Infiltrating ductal carcinoma was the principal histopathological type 91.66% (n = 110). Receptor analysis revealed ER/PR + HER-2neu as the most common type 40% (n = 18) for therapeutic surveillance. Conclusion: This study highlights various epidemiological factors that influence the development of BCa among females in TnT. Histopathological analysis and receptor studies would provide a useful link between the tumor behavior and its prognosis.

7.
Sci Adv ; 6(45)2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33148641

RESUMEN

Rising sea levels have been associated with human migration and behavioral shifts throughout prehistory, often with an emphasis on landscape submergence and consequent societal collapse. However, the assumption that future sea-level rise will drive similar adaptive responses is overly simplistic. While the change from land to sea represents a dramatic and permanent shift for preexisting human populations, the process of change is driven by a complex set of physical and cultural processes with long transitional phases of landscape and socioeconomic change. Here, we use reconstructions of prehistoric sea-level rise, paleogeographies, terrestrial landscape change, and human population dynamics to show how the gradual inundation of an island archipelago resulted in decidedly nonlinear landscape and cultural responses to rising sea levels. Interpretation of past and future responses to sea-level change requires a better understanding of local physical and societal contexts to assess plausible human response patterns in the future.

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