Marsh archive reveals human population history and future implications for estuarine health in Long Island Sound.

Coastal marshes are efficient ecosystems providing a multitude of benefits for invertebrates, birds, fish and humans alike. Yet despite these benefits, wetlands are threatened by anthropogenic inputs such as human wastewater which contain high levels of nitrogen (N). Increased nitrogen loads cause eutrophication and hypoxia in estuaries leading to further degradation of these valuable ecosystems that are already stressed by sea level rise and climate change. Policies to protect wetlands via wastewater treatments are reactive rather than proactive and a growing body of research shows that characteristics associated with population health and economic activity can be identified in wastewater. Analysis of a 2-m salt marsh sediment core reveals δN15 signatures indicative of human population rise and connects human impact to ecosystem health. Using key X-ray fluorescence (XRF), pollen, sediment and nitrogen signatures along the core, a robust chronology was produced dating back to 1700. This result was coupled with population data to observe the relationship between δN15 levels and population over three centuries. There is a statistically significant positive correlation between δN15 and population. Other external factors such as federal government policies (regulating clean water) show a clear reduction in this association but the use of synthetic nitrogen fertilizer masks the strength of this relationship. Further research to refine the relationship between population and δN15 could be beneficial in predicting nitrogen loads as human population grows, which in turn would create a proactive system to protect our coastal ecosystems.

Arctic ice and the ecological rise of the dinosaurs.

Abundant lake ice-rafted debris in Late Triassic and earliest Jurassic strata of the Junggar Basin of northwestern China (paleolatitude ~71°N) indicates that freezing winter temperatures typified the forested Arctic, despite a persistence of extremely high levels of atmospheric Pco2 (partial pressure of CO2). Phylogenetic bracket analysis shows that non-avian dinosaurs were primitively insulated, enabling them to access rich deciduous and evergreen Arctic vegetation, even under freezing winter conditions. Transient but intense volcanic winters associated with massive eruptions and lowered light levels led to the end-Triassic mass extinction (201.6 Ma) on land, decimating all medium- to large-sized nondinosaurian, noninsulated continental reptiles. In contrast, insulated dinosaurs were already well adapted to cold temperatures, and not only survived but also underwent a rapid adaptive radiation and ecological expansion in the Jurassic, taking over regions formerly dominated by large noninsulated reptiles.

Sediment starvation destroys New York City marshes' resistance to sea level rise.

New York City (NYC) is representative of many vulnerable coastal urban populations, infrastructures, and economies threatened by global sea level rise. The steady loss of marshes in NYC's Jamaica Bay is typical of many urban estuaries worldwide. Essential to the restoration and preservation of these key wetlands is an understanding of their sedimentation. Here we present a reconstruction of the history of mineral and organic sediment fluxes in Jamaica Bay marshes over three centuries, using a combination of density measurements and a detailed accretion model. Accretion rate is calculated using historical land use and pollution markers, through a wide variety of sediment core analyses including geochemical, isotopic, and paleobotanical analyses. We find that, since 1800 CE, urban development dramatically reduced the input of marsh-stabilizing mineral sediment. However, as mineral flux decreased, organic matter flux increased. While this organic accumulation increase allowed vertical accumulation to outpace sea level, reduced mineral content causes structural weakness and edge failure. Marsh integrity now requires mineral sediment addition to both marshes and subsurface channels and borrow pits, a solution applicable to drowning estuaries worldwide. Integration of marsh mineral/organic accretion history with modeling provides parameters for marsh preservation at specific locales with sea level rise.

Prevalencia de cardiopatía isquémica asintomática en pacientes con diabetes mellitus tipo 2 / Prevalence of asymptomatic ischaemic heart disease in patients with type 2 diabetes mellitus

Resumen Introducción: La enfermedad cardiovascular es la causa principal de muerte en pacientes con diabetes mellitus. La prevalencia de cardiopatía isquémica asintomática es más alta en pacientes diabéticos que en no diabéticos y se asocia a peor pronóstico. Objetivo: Identificar la prevalencia de cardiopatía isquémica asintomática en pacientes con diabetes mellitus tipo 2 en un hospital de tercer nivel de atención de Guatemala y analizar la posible asociación de dicha enfermedad con características epidemiológicas, clínicas y metabólicas. Métodos: Estudio de corte transversal en el que se estudió una muestra de 92 pacientes diabéticos seleccionados de forma aleatoria simple. Se realizó electrocardiograma, que cuando fue negativo para isquemia ameritó prueba de esfuerzo, o de lo contrario, ecocardiograma de estrés con dobutamina. Resultados: La edad media de los participantes fue de 57 años, 88% de los cuales eran mujeres; la duración media de la diabetes fue 7 años. Se encontró cardiopatía isquémica asintomática en el 22,8% de los casos. No se hallaron posibles asociaciones entre cardiopatía isquémica asintomática y edad, sexo, enfermedad arterial periférica, índice de masa corporal, índice tobillo-brazo, hipertensión arterial, dislipidemia, tabaquismo activo, sedentarismo, sobrepeso/obesidad, alcoholismo, glucosa en ayunas, hemoglobina glicosilada, colesterol total, colesterol HDL, colesterol LDL, ácido úrico, creatinina, tasa de filtrado glomerular y microalbuminuria. Conclusiones: La prevalencia de cardiopatía isquémica asintomática en la población estudiada con diabetes mellitus tipo 2 fue de 22,8%. No se encontraron posibles asociaciones de cardiopatía isquémica asintomática con las variables estudiadas.

Abstract Introduction: Cardiovascular disease is the main cause of death in patients with diabetes mellitus. The prevalence of asymptomatic ischaemic heart disease is higher in diabetic patients than in non-diabetic ones, and is associated with a worse prognosis. Objective: To determine the prevalence of asymptomatic ischaemic heart disease in patients with type 2 diabetes mellitus in a third level of care hospital in Guatemala, as well as to analyse the possible relationship of this disease with epidemiological, clinical, and metabolic characteristics. Methods: A cross-sectional study was conducted on a sample of 92 randomly selected diabetic patients. An electrocardiogram was performed, which when it was negative for ischaemia, an exercise stress test or a dobutamine stress echocardiogram was performed. Results: The mean age of the participants was 57 years, 88% of whom were women. The mean duration of the diabetes was 7 years. Asymptomatic ischaemic heart disease was found in 22.8% of case. No significant associations were found between ischaemic heart disease and age, gender, peripheral arterial disease, body mass index, ankle-brachial index, arterial hypertension, dyslipidaemia, active smoking, sedentarism, overweight/obesity, alcoholism, fasting glucose, glycosylated haemoglobin, total cholesterol, HDL-cholesterol, LDL-cholesterol, uric acid, creatinine, glomerular filtration rate, and urine microalbumin. Conclusions: The prevalence of asymptomatic ischaemic heart disease was 22.8% in the population studied with type 2 diabetes mellitus. No significant associations were found between ischaemic heart disease and the variables studied.

Prevalencia de Micro albuminuria en pacientes hipertensos no diabéticos

Introducción: Se ha demostrado que la presencia de micro albuminuria puede reflejar el desarrollo de enfermedad cardiovascular en pacientes con diabetes mellitus, este fenómeno también se ha observado en pacientes no diabéticos. Objetivo: Determinar la prevalencia de micro albuminuria en pacientes hipertensos no diabéticos tratados en la Consulta Externa del Hospital General San Juan de Dios. Métodos: Medición de micro albuminuria con tira reactiva urinaria Micral-Test® en 86 pacientes con hipertensión esencial de 1 a 10 años de evolución. Resultados: Se encontró una prevalencia total de micro albuminuria de 81%. Con ICC se encontró diferencia estadísticamente significativa entre el grupo de pacientes que presentó micro albuminuria con 99% de significancia. (p 0.03) IC 95%. No se encontró diferencia estadísticamente significativa entre los grupos de pacientes con y sin micro albuminuria con el resto de variables a estudio.

Introduction: It known that the presence of microalbuminuria can reflect the development of cardiovascular disease in patients with or without diabetes. Objective: To determine the prevalence of microalbuminuria in hypertensive non diabetic patients treated in the outpatient clinic for hypertension in Hospital General San Juan de Dios. Methods: Measure of microalbuminuria using the Micral-Test® reactive urine strip in 86 patients with 1 to 10 years of being diagnosed with essential hypertension. Results: Total prevalence of microalbuminuria was 81%. CHF had statistical difference between the group of patients with and without microalbuminuria with 99% of significance (p 0.03). There was not statistical difference between the group of patients with and without microalbuminuria in the rest of the variables studied.