Lakes emit substantial amounts of carbon dioxide (CO) into the atmosphere, but why they do remains debated. The long-standing vision of lakes as solely respirators of the organic matter leaking from the soils has been challenged by evidence that inorganic carbon produced by weathering of the catchment bedrock could also support lake CO emissions. How inorganic carbon inputs ultimately generate lake CO outgassing remains a blind spot.
View Article and Find Full Text PDFMethane (CH) accumulation in the well-oxygenated lake epilimnion enhances the diffusive atmospheric CH emission. Both lateral transport and in situ oxic methane production (OMP) have been suggested as potential sources. While the latter has been recently supported by increasing evidence, quantifying the exact contribution of OMP to atmospheric emissions remains challenging.
View Article and Find Full Text PDFFreshwater algae exhibit complex dynamics, particularly in meso-oligotrophic lakes with sudden and dramatic increases in algal biomass following long periods of low background concentration. While the fundamental prerequisites for algal blooms, namely light and nutrient availability, are well-known, their specific causation involves an intricate chain of conditions. Here we examine a recent massive Uroglena bloom in Lake Geneva (Switzerland/France).
View Article and Find Full Text PDFThe extent of littoral influence on lake gas dynamics remains debated in the aquatic science community due to the lack of direct quantification of lateral gas transport. The prevalent assumption of diffusive horizontal transport in gas budgets fails to explain anomalies observed in pelagic gas concentrations. Here, we demonstrate through high-frequency measurements in a eutrophic lake that daily convective horizontal circulation generates littoral-pelagic advective gas fluxes one order of magnitude larger than typical horizontal fluxes used in gas budgets.
View Article and Find Full Text PDFIntroduction: Bioconvection, a phenomenon characterized by the collective upward swimming of motile microorganisms, has mainly been investigated within controlled laboratory settings, leaving a knowledge gap regarding its ecological implications in natural aquatic environments. This study aims to address this question by investigating the influence of bioconvection on the eco-physiology of the anoxygenic phototrophic sulfur bacteria community of meromictic Lake Cadagno.
Methods: Here we comprehensively explore its effects by comparing the physicochemical profiles of the water column and the physiological traits of the main populations of the bacterial layer (BL).
Three-dimensional lake hydrodynamic model is a powerful tool widely used to assess hydrological condition changes of lake. However, its computational cost becomes problematic when forecasting the state of large lakes or using high-resolution simulation in small-to-medium size lakes. One possible solution is to employ a data-driven emulator, such as a deep learning (DL) based emulator, to replace the original model for fast computing.
View Article and Find Full Text PDFChromium stable isotope composition (δCr) is a promising tracer for redox conditions throughout Earth's history; however, the geochemical controls of δCr have not been assessed in modern redox-stratified basins. We present new chromium (Cr) concentration and δCr data in dissolved, sinking particulate, and sediment samples from the redox-stratified Lake Cadagno (Switzerland), a modern Proterozoic ocean analog. These data demonstrate isotope fractionation during incomplete (non-quantitative) reduction and removal of Cr above the chemocline, driving isotopically light Cr accumulation in euxinic deep waters.
View Article and Find Full Text PDFSevere deterioration of water quality in lakes, characterized by overabundance of algae and declining dissolved oxygen in the deep lake (DO), was one of the ecological crises of the 20th century. Even with large reductions in phosphorus loading, termed "reoligotrophication," DO and chlorophyll (CHL) have often not returned to their expected pre-20th-century levels. Concurrently, management of lake health has been confounded by possible consequences of climate change, particularly since the effects of climate are not neatly separable from the effects of eutrophication.
View Article and Find Full Text PDFIn recent decades, lakes have experienced unprecedented ice loss with widespread ramifications for winter ecological processes. The rapid loss of ice, resurgence of winter biology, and proliferation of remote sensing technologies, presents a unique opportunity to integrate disciplines to further understand the broad spatial and temporal patterns in ice loss and its consequences. Here, we summarize ice phenology records for 78 lakes in 12 countries across North America, Europe, and Asia to permit the inclusion and harmonization of in situ ice phenology observations in future interdisciplinary studies.
View Article and Find Full Text PDFSAGE Open Med Case Rep
April 2022
Bullous pemphigoid is an autoimmune blistering disease that primarily affects the geriatric population. It often presents as urticarial erythematous plaques, which evolve into subepidermal blisters accompanied by pruritus. Although rare, clinical variants of bullous pemphigoid have been documented.
View Article and Find Full Text PDFAnomaly detection is the process of identifying unexpected data samples in datasets. Automated anomaly detection is either performed using supervised machine learning models, which require a labelled dataset for their calibration, or unsupervised models, which do not require labels. While academic research has produced a vast array of tools and machine learning models for automated anomaly detection, the research community focused on environmental systems still lacks a comparative analysis that is simultaneously comprehensive, objective, and systematic.
View Article and Find Full Text PDFWater inherent optical properties (IOPs) contain integrative information on the optical constituents of surface waters. In lakes, IOP measurements have not been traditionally collected. This study describes how high-frequency IOP profiles can be used to document short-term physical and biogeochemical processes that ultimately influence the long-term trajectory of lake ecosystems.
View Article and Find Full Text PDFA 66-year-old woman presented to the hospital with cutaneous necrosis of her right ankle and foot. Her symptoms began immediately after an intra-articular injection of hyaluronic acid for ankle osteoarthritis, which was performed 6 days before. Histopathology showed an intra-vascular hyaluronic acid embolus.
View Article and Find Full Text PDFWater-level fluctuation (WLF) is a widespread management action in lakes and reservoirs whose impacts on contaminant fate have seldom been investigated. We used near shore hourly measurements (n = 2122) of turbidity (contaminant proxy) and water velocity (sediment resuspension proxy) to track high-frequency contaminant dynamics during a 0.6 m change in water level observed in autumn 2017 in a large French lake.
View Article and Find Full Text PDFAllergy Asthma Clin Immunol
February 2020
Background: Acute generalized exanthematous pustulosis (AGEP) and toxic epidermal necrolysis (TEN) are severe cutaneous adverse reactions. These rare conditions differ in clinical presentation, pathological features, treatment and prognosis, but overlap has been described implying a challenging clinical management.
Case Presentation: We describe a case of overlap between TEN and AGEP probably secondary to beta-lactams in a 77-year-old patient treated for a complicated cholangitis.
Environmental management depends on high-quality monitoring and its meaningful interpretation. The combination of local weather dynamics, regional anthropogenic stresses and global environmental changes make the evaluation of monitoring information in dynamic freshwater systems a challenging task. While the lake ecosystems gather many complex biogeochemical interactions, they remain constrained by the same physical environment of mixing and transport.
View Article and Find Full Text PDFA 28-year-old woman of Chinese descent, with congenital chronic hepatitis B presented with a 7-year history of erythematous-brown papules and plaques on her groins, axillae, and forehead. A first skin biopsy showed findings consistent with two concomitant, yet highly uncommon cutaneous diseases. The presence of lymphoid nodules with germinal centers and clustered polyclonal plasma cells was consistent with cutaneous plasmocytosis.
View Article and Find Full Text PDFSAGE Open Med Case Rep
December 2018
Cutaneous adenosquamous carcinoma is a rare malignant neoplasm that is more aggressive than conventional squamous cell carcinoma. The typical clinical presentation is an indurated papule or plaque on the head and neck of elderly patients. The authors report the case of a 52-year-old man with a right scrotal and inguinal tumour measuring 10 cm × 15 cm that had progressed over the past 2 years.
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