8 research outputs found

    Head and Neck Cancers

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    This chapter in Cancer Concepts: A Guidebook for the Non-Oncologist presents an overview of head and neck cancers, including epidemiology, etiology, screening, pathology, staging, and treatment. The chapter focuses on cancers of the upper aerodigestive tract which are most often squamous cell carcinomas arising from the squamous epithelium that lines the tract.https://escholarship.umassmed.edu/cancer_concepts/1021/thumbnail.jp

    Standard Versus Natural: Assessing the Impact of Environmental Variables on Organic Matter Decomposition in Streams Using Three Substrates

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    The decomposition of allochthonous organic matter, such as leaves, is a crucial ecosystem process in low-order streams. Microbial communities, including fungi and bacteria, colonize allochthonous organic material, break up large molecules, and increase the nutritional value for macroinvertebrates. Environmental variables are known to affect microbial as well as macroinvertebrate communities and alter their ability to decompose organic matter. Studying the relationship between environmental variables and decomposition has mainly been realized using leaves, with the drawbacks of differing substrate composition and consequently between-study variability. To overcome these drawbacks, artificial substrates have been developed, serving as standardizable surrogates. In the present study, we compared microbial and total decomposition of leaves with the standardized substrates of decotabs and, only for microbial decomposition, of cotton strips, across 70 stream sites in a Germany-wide study. Furthermore, we identified the most influential environmental variables for the decomposition of each substrate from a range of 26 variables, including pesticide toxicity, concentrations of nutrients, and trace elements, using stability selection. The microbial as well as total decomposition of the standardized substrates (i.e., cotton strips and decotabs) were weak or not associated with that of the natural substrate (i.e., leaves, r(2) < 0.01 to r(2) = 0.04). The decomposition of the two standardized substrates, however, showed a moderate association (r(2) = 0.21), which is probably driven by their similar composition, with both being made of cellulose. Different environmental variables were identified as the most influential for each of the substrates and the directions of these relationships contrasted between the substrates. Our results imply that these standardized substrates are unsuitable surrogates when investigating the decomposition of allochthonous organic matter in streams. Environ Toxicol Chem 2023;00:1-12. (c) 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC

    Standard Versus Natural: Assessing the Impact of Environmental Variables on Organic Matter Decomposition in Streams Using Three Substrates

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    AbstractThe decomposition of allochthonous organic matter, such as leaves, is a crucial ecosystem process in low‐order streams. Microbial communities, including fungi and bacteria, colonize allochthonous organic material, break up large molecules, and increase the nutritional value for macroinvertebrates. Environmental variables are known to affect microbial as well as macroinvertebrate communities and alter their ability to decompose organic matter. Studying the relationship between environmental variables and decomposition has mainly been realized using leaves, with the drawbacks of differing substrate composition and consequently between‐study variability. To overcome these drawbacks, artificial substrates have been developed, serving as standardizable surrogates. In the present study, we compared microbial and total decomposition of leaves with the standardized substrates of decotabs and, only for microbial decomposition, of cotton strips, across 70 stream sites in a Germany‐wide study. Furthermore, we identified the most influential environmental variables for the decomposition of each substrate from a range of 26 variables, including pesticide toxicity, concentrations of nutrients, and trace elements, using stability selection. The microbial as well as total decomposition of the standardized substrates (i.e., cotton strips and decotabs) were weak or not associated with that of the natural substrate (i.e., leaves, r² &lt; 0.01 to r² = 0.04). The decomposition of the two standardized substrates, however, showed a moderate association (r² = 0.21), which is probably driven by their similar composition, with both being made of cellulose. Different environmental variables were identified as the most influential for each of the substrates and the directions of these relationships contrasted between the substrates. Our results imply that these standardized substrates are unsuitable surrogates when investigating the decomposition of allochthonous organic matter in streams. Environ Toxicol Chem 2023;42:2007–2018. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659Umweltbundesamt http://dx.doi.org/10.13039/501100010809https://doi.org/10.1594/PANGAEA.93167

    From a stratigraphic sequence to a landscape evolution model: Late Pleistocene and Holocene volcanism, soil formation and land use in the shade of Mount Vesuvius (Italy).

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    Detailed lithostratigraphic, geochemical, pedological, micromorphological and archaeological analyses were carried out at a stratigraphic sequence of Scafati, about 3 km east of ancient Pompeii. It comprises roughly the last 22,000 years of landscape history consisting of a multilayered succession of repeated volcanic deposition and pedogenesis. The former is caused by several phases of volcanic activity of Somma-Vesuvius, Campi Flegrei and Ischia, reflecting a large spectrum of eruption types including Plinian, sub-Plinian, Strombolian to Vulcanian and effusive volcanic events. The latter contains phases of volcanic quiescence leading to soil formations of different durations, intensities and soil-forming environments. Furthermore, the paleosols repeatedly reveal clear evidence of anthropogenic activity such as agriculture. Using this multiproxy approach, a holistic landscape evolution model was developed reconstructing the late Pleistocene and Holocene history of volcanic activity, soil formation and land use in the hinterland of Pompeii. This was correlated with the larger-scale climatic and human history of the Campania region. © 2015 Elsevier Ltd and INQUA

    Assessing the mixture effects in in vitro bioassays of chemicals occurring in small agricultural streams during rain events

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    Rain events may impact the chemical pollution burden in rivers. Forty-four small streams in Germany were profiled during several rain events for the presence of 395 chemicals and five types of mixture effects in in vitro bioassays (cytotoxicity; activation of the estrogen, aryl hydrocarbon, and peroxisome proliferator-activated receptors; and oxidative stress response). While these streams were selected to cover a wide range of agricultural impacts, in addition to the expected pesticides, wastewater-derived chemicals and chemicals typical for street runoff were detected. The unexpectedly high estrogenic effects in many samples indicated the impact by wastewater or overflow of combined sewer systems. The 128 water samples exhibited a high diversity of chemical and effect patterns, even for different rain events at the same site. The detected 290 chemicals explained only a small fraction

    The lowland stream monitoring dataset (KgM, Kleingewässer-Monitoring) 2018, 2019

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    Plant protection products in the environment are partly responsible for the progressive loss of biodiversity. The mostly insufficient ecological status of surface waters is often explained by habitat degradation and excessive nutrient input. But what role do plant protection products play in this context? The Kleingewässermonitoring (KgM) project provides a worldwide unique quantitative assessment of the impact of pesticides from diffuse agricultural sources on small and medium-sized streams. The dataset comprises 124 monitoring stream sections all over Germany covering a wide pollution gradient where consistent measurements were carried out in 2018 and 2019 during the major pesticide application period from April to July. These measurements include event-driven sampling to record surface rainfall-induced short-term peak concentrations in addition to regular grab sampling of pesticides and a wide range of other pollutants resulting in more than 1,000 water samples. All further relevant anthropogenic and environmental parameters reigning ecological stream quality were recorded comprehensively (morphological and stream bed structure, temperature, flow velocity, dissolved oxygen, pH, catchment land use, stream profile). The dataset also contains effect monitoring data featuring sampled invertebrate communities and bioassay analyses of water samples. The data enables an assessment of pesticide exposure and related effects as well as the analysis of complex causal relationships in streams

    Biome-Scale Forest Properties in Amazonia Based on Field and Satellite Observations

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    Amazonian forests are extremely heterogeneous at different spatial scales. This review intends to present the large-scale patterns of the ecosystem properties of Amazonia, and focuses on two parts of the main components of the net primary production: the long-lived carbon pools (wood) and short-lived pools (leaves). First, the focus is on forest biophysical properties, and secondly, on the macro-scale leaf phenological patterns of these forests, looking at field measurements and bringing into discussion the recent findings derived from remote sensing dataset. Finally, I discuss the results of the three major droughts that hit Amazonia in the last 15 years. The panorama that emerges from this review suggests that slow growing forests in central and eastern Amazonia, where soils are poorer, have significantly higher above ground biomass and higher wood density, trees are higher and present lower proportions of large-leaved species than stands in northwest and southwest Amazonia. However, the opposite pattern is observed in relation to forest productivity and dynamism, which is higher in western Amazonia than in central and eastern forests. The spatial patterns on leaf phenology across Amazonia are less marked. Field data from different forest formations showed that new leaf production can be unrelated to climate seasonality, timed with radiation, timed with rainfall and/or river levels. Oppositely, satellite images exhibited a large-scale synchronized peak in new leaf production during the dry season. Satellite data and field measurements bring contrasting results for the 2005 drought. Discussions on data processing and filtering, aerosols effects and a combined analysis with field and satellite images are presented. It is suggested that to improve the understanding of the large-scale patterns on Amazonian forests, integrative analyses that combine new technologies in remote sensing and long-term field ecological data are imperative
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