We investigated the atmospheric processes and physics that were active during a tsunami-like event hitting Boothbay Harbor area (Maine, USA) on 28 October 2008. The data collected by tide gauges, ...ground and sounding stations and meteo–ocean buoys in the area were analyzed, together with satellite and radar images. The atmospheric processes were reproduced by the weather research and forecasting model, verified by in situ and remote sensing data. A cold front moved over the area at the time of the event, with embedded convective clouds detected by satellite and radar data and the internal gravity waves (IGWs) detected by radar and reproduced by the model at the rear of the frontal precipitation band. According to the model, the IGWs that passed over Boothbay Harbor generated strong ground air-pressure oscillations reaching 2.5 hPa/3 min. The IGWs were ducted towards the coast without significant dissipation, propagating in a stable near-surface layer capped by an instability at approximately 3.5 km height and satisfying all conditions for their maintenance over larger areas. The intensity, speed and direction of the IGWs were favourable for generation of a meteotsunami wave along the Gulf of Maine shelf. Operational observation systems were not capable of sufficiently capturing the ground disturbance due to a too coarse sampling rate, while the numerical model was found to be a useful tool in eventual future detection and warning systems.
We investigated the interactions among pH, Al solubility and Al–soil organic matter (SOM) complexation to test the hypothesis that competition between Al and H ions for cation binding sites on soil ...organic matter (SOM) determines soil pH and Al solubility in acidic forest soils in the northeastern U.S. Samples from five soil horizons in 39 forested watersheds across the northeastern U.S. were used with two Al complexation models to test the hypothesis. Our results indicated that Al solubility increases with soil depth when pH is less than 4.5 and the ratio of the fractions of organically bound Al and H(NAl/NH) or the ratio of organically bound Al to total organic carbon (Alorg/C) remains roughly constant within each horizon. Both the NAl/NH and the Alorg/C ratios are effective measures of the ratio of sites bound to Al and H in Al–SOM complexation models. The log-linear relationship pAlKCl-p(Alorg/C)=0.75×pHKCl-1.56 (r=0.86,P<.0001) can be used to describe Al–pH relationships in Oie, Oa, Bh and Bs1 horizon samples from across the region. The competition between H+ and Al3+ for binding to SOM affects soil pH and Al solubility to a greater degree in Oa and Bs1 horizons than in Oie and E horizons. Our data are consistent with the conceptual model that portrays the Al–pH relationship in acid forest soils as a balance between organic acidity and alkalinity produced through the weathering of aluminosilicate minerals.
•pH, Al solubility and Al–SOM complexes control acid–base chemistry in forest soils.•Two Al binding/solubility models were tested with data from the northeastern USA.•The effects of Al saturation must be considered in the Al–SOM complexation models.•Al–H competition controls pH and Al solubility in Oa and upper mineral horizons.•Base cations compete with exchangeable H ions to regulate pH in Oi/Oe horizons.
The role of anaerobic oxidation of methane (AOM) in wetlands, the largest natural source of atmospheric methane, is poorly constrained. Here we report rates of microbially mediated AOM (average ...rate=20 nmol cm(-3) per day) in three freshwater wetlands that span multiple biogeographical provinces. The observed AOM rates rival those in marine environments. Most AOM activity may have been coupled to sulphate reduction, but other electron acceptors remain feasible. Lipid biomarkers typically associated with anaerobic methane-oxidizing archaea were more enriched in (13)C than those characteristic of marine systems, potentially due to distinct microbial metabolic pathways or dilution with heterotrophic isotope signals. On the basis of this extensive data set, AOM in freshwater wetlands may consume 200 Tg methane per year, reducing their potential methane emissions by over 50%. These findings challenge precepts surrounding wetland carbon cycling and demonstrate the environmental relevance of an anaerobic methane sink in ecosystems traditionally considered strong methane sources.
O presente artigo tem como objetivo descrever o corpo subjetivo em Michel Henry. Partindo da concepção de subjetividade como pertencente ao ser originário e imanente, ser do ego, Henry descreve a ...materialidade subjetiva relacionada ao corpo. Se utilizando da teoria de Maine de Biran, na obra Filosofia e fenomenologia do corpo, ele apresenta o corpo subjetivo como revelação do próprio ser e do próprio ego na imanência pura. Assim, seus movimentos são manifestações originárias imanentes que se dão no corpo, o qual possui sabedoria própria, portanto, de onde advém todo conhecimento verdadeiro de si mesmo. Pelo Eu posso ocorre o movimento subjetivo que abre a possibilidade para todo o conhecimento. Por fim, essa manifestação imanente da subjetividade se dá como experiência interna transcendental através dos elementos transcendentes do corpo, revelando o ser originário. Palavras-chave: Subjetividade. Corpo. Maine de Biran. Movimento. This article aims to describe the subjective body in Michel Henry. Starting from the concept of subjectivity as belonging to the original and immanent being, being of the ego, Henry describes a material subjetive for the body. If he uses Maine of Biran's theory, in the work Philosophy and phenomenology of the body, he presents the subjective body as a revelation of one's being and ego in pure immanence. Thus, its movements are manifestations originating immanents that occur in the body, which has its own wisdom, therefore, where all true self-knowledge comes from. As far as I can occur or the subjective movement that opens the possibility of all knowledge. Finally, this immanent manifestation of subjectivity occurs as the transcendental internal experience through the transcendent elements of the body, revealing or being original. Keywords: Subjectivity. Body. Maine de Biran. Movement.
This research reports on the health status, including chronic disease risk factors, among Maine loggers.
Loggers completed a survey and health screenings were held across Maine, collecting data on a ...variety of health endpoints.
Seventy-five loggers participated. The majority were men (97.1%) with a median age of 46, and a mean BMI of 30.6 kg/m2 (SD 4.9). Nearly half of those screened (45.9%) had blood pressure at the level of stage II hypertension. Loggers with at least a single joint abnormality were 38.4%. The health screening cohort was similar to the non-health screening cohort for many attributes.
Future research should focus on tailored interventions to improve cardiovascular and musculoskeletal risk factors among loggers.
Rapakivi and alkali feldspar phenocrysts from the Devonian Deer Isle Granite Complex, Maine were investigated to see if magma mixing or isothermal decompression was responsible for their formation. ...Pb-isotope and trace-element analyses of alkali feldspar ovoids and their plagioclase inclusions were obtained by LA-ICP-MS to determine the characteristics of the initial magma; these were compared with the plagioclase mantles. Rapakivi grains show a decrease in Pb-isotopic values and an increase in Ba, La, and Ce concentrations from the ovoids and inclusions to the innermost plagioclase mantles adjacent to the ovoids. These variations, along with CL imagery of quartz phenocrysts, indicate an open system with compositional changes in the magma chamber occurring during rapakivi feldspar growth. Repeated episodes of magma mixing/replenishment by Ba and LREE enriched magmas with lower Pb-isotopic ratios (along with hybridized variations with the host magma) created localized dissolution of alkali feldspar and quartz. Alkali feldspar phenocrysts proximal to these zones of thermal perturbation were first resorbed and then mantled by plagioclase that records the more primitive signature of the more mafic melt. Pb-isotopic values and Ba, La, and Ce concentrations trend back to the initial magma composition at the mantle rims as the effects of the mixing event dissipated. For grains that were somewhat more distal to these zones of mixing, resorption of the alkali feldspar crystals did not occur, yet the fresh supply of Ba resulted in Ba-rich alkali feldspar mantles over Ba-poor alkali feldspar cores. Other alkali feldspar crystals were too far from the site of mixing; hence, they lack any evidence of open system crystallization. As crystallization of the chamber continued along solidification fronts, batches of cooler crystal-rich magmas settled
en masse
to the floor. Disaggregation of these batches during settling, and subsequent accumulation on the reservoir floor, brought grains with disparate crystallization histories together. Filter pressing of the cumulate pile flushed highly evolved melts/fluids out from interstitial pores to the high silica, upper portions of the chamber. The crystallization, transportation, and juxtaposition of disparate types of feldspar phenocrysts suggest that a relatively large and active magma chamber, periodically recharged by localized batches of melt, must have existed. In this case, it is clear that rapakivi mantled feldspars are the result of magma mixing; such interpretations may apply to many other occurrences as well.
Titanite is a potentially powerful U–Pb petrochronometer that may record metamorphism, metasomatism, and deformation. Titanite may also incorporate significant inherited Pb, which may lead to ...inaccurate and geologically ambiguous U–Pb dates if a proper correction is not or cannot be applied. Here, we present laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS)‐derived titanite U–Pb dates and trace element concentrations for two banded calcsilicate gneisses from south‐central Maine, USA (SSP18‐1A and SSP18‐1B). Single spot common Pb‐corrected dates range from 400 to 280 Ma with ±12–20 Ma propagated 2SE. Titanite grains in sample SSP18‐1B exhibit regular core‐to‐rim variations in texture, composition, and date. We identify four titanite populations: (1) 397 ± 5 Ma (95% CL) low Y + HREE cores and mottled grains, (2) 370 ± 7 Ma high Y + REE mantles and cores, (3) 342 ± 6 Ma cores with high Y + REE and no Eu anomaly, and (4) 295 ± 6 Ma LREE‐depleted rims. We interpret the increase in titanite Y + HREE between ca. 397 and ca. 370 Ma to constrain the timing of diopside fracturing and recrystallization and amphibole breakdown. Apparent Zr‐in‐titanite temperatures (803 ± 36°C at 0.5 ± 0.2 GPa) and increased XDi suggest a thermal maximum at ca. 370 Ma. Population 3 domains dated to ca. 342 Ma exhibit no Eu anomaly and are observed only in compositional bands dominated by diopside (>80 vol%), suggesting limited equilibrium between titanite and plagioclase. Finally, low LREE and high U/Th in Population 4 titanite dates the formation of hydrous phases, such as allanite, during high XH2O fluid infiltration at ca. 295 Ma. In contrast to the well‐defined date–composition–texture relationships observed for titanite from SSP18‐1B, titanite grains from sample SSP18‐1A exhibit complex zoning patterns and little correlation between texture, composition, and date. We hypothesize that the incorporation of variable amounts of radiogenic Pb from dissolved titanite into recrystallized domains resulted in mixed dates spanning 380–330 Ma. Although titanite may reliably record multiple phases of metamorphism, these data highlight the importance of considering U–Pb data along with chemical and textural data to screen for inherited radiogenic Pb.
One Environmental Health has emerged as an important area of research that considers the interconnectedness of human, animal and ecosystem health with a focus on toxicology. The great whales in the ...Gulf of Maine are important species for ecosystem health, for the economies of the Eastern seaboard of the United States, and as sentinels for human health. The Gulf of Maine is an area with heavy coastal development, industry, and marine traffic, all of which contribute chronic exposures to environmental chemicals that can bioaccumulate in tissues and may gradually diminish an individual whale's or a population's fitness. We biopsied whales for three seasons (2010–2012) and measured the levels of 25 metals and selenium in skin biopsies collected from three species: humpback whales (Megaptera novaeangliae), fin whales (Balaenoptera physalus), and a minke whale (Balaenoptera acutorostrata). We established baseline levels for humpback and fin whales. Comparisons with similar species from other regions indicate humpback whales have elevated levels of aluminum, chromium, iron, magnesium, nickel and zinc. Contextualizing the data with a One Environmental Health approach finds these levels to be of potential concern for whale health. While much remains to understand what threats these metal levels may pose to the fitness and survival of these whale populations, these data serve as a useful and pertinent start to understanding the threat of pollution.
•Gulf of Maine whales exhibited metal levels in their skin tissues.•Chromium levels in the whales were similar to levels reported in exposed workers.•Nickel levels in the whales were similar to levels reported in exposed workers.
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