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Greenhouse gas emissions (CO2âCH4âN2O) along a large reservoirâdownstream river continuum: The role of seasonal hypoxia
Recent studies suggest that hypolimnetic respiration may be responsible for greenhouse gas (GHG) emissions from deep reservoirs. Currently, quantitative evaluation of aerobic vs. anaerobic processes and priming (enhanced processing of organic matter due to the addition of labile carbon) in regulating GHG production and emissions across the reservoir-downstream continuum remains largely unknown. High-resolution, annual time-series observations in a large, subtropical reservoir (Shuikou) experiencing seasonal hypoxia in southeast China indicate that aerobic hypolimnetic CO2 production dominated in most periods of the stratified spring/summer with higher rates at higher temperatures. In addition, anaerobic production of hypolimnetic CO2 occurred in the late stratified spring/summer period, which stimulated hypolimnetic production of CH4 and N2O. Incubation experiments showed that priming in spring enhanced both aerobic and anaerobic production of excess GHGs. A late spring flood event generated the highest daily efflux of CO2 through the flushing of GHG-enriched hypolimnion waters. Turbine degassing contributed 59%, 93%, and 63% of annual CO2, CH4, and N2O effluxes, respectively. Moreover, annual downstream GHG emissions were similar to those in the transition/lacustrine zone of the Shuikou reservoir. Diurnal variation observations revealed net CO2 emissions even during algal bloom seasons. The reservoir-downstream river continuum was a year-round source of GHGs (218.5 ± 18.9 Gg CO2-equivalent yrâ1; CO2 contributed 91%). However, the loss of oxygen also leads to increased production and storage of recalcitrant dissolved organic carbon (RDOC). Thus, identifying mechanisms controlling both GHG emissions and RDOC production is crucial to constrain the carbon neutrality issue of hydroelectric reservoirs in the context of climate change mitigation strategies
Multi-scale Designed CoxMn3âxO4 Spinels : Smart Pre-Catalysts towards High-Efficiency Pyrolysis-Catalysis Recycling of Waste Plastics
Acknowledgements M. W. and A. W. highly acknowledge the funding by the German Federal Ministry of Education and Research (BMBF) within the NexPlas project (project number: 03SF0618B). Y. S. Z is grateful for financial supports provided by the Royal Society of Chemistry Enablement Grant (E21-5819318767) and Royal Society of Chemistry Mobility Grant (M19-2899).Peer reviewedPostprin
Successful treatment of Giant keloid on the right toes using trepanation combined with superficial radiotherapy (SRT-100): a case report with literature review
In dermatology, a keloid is one of the most common skin morphological abnormalities caused by excessive proliferation of fibroblasts. Keloids that are large or occur near important joint sites often cause varying degrees of physiological dysfunction in patients, therefore requiring medical treatment. A boy with congenital syndactyly developed huge keloids at the surgical site after undergoing surgical correction treatment. After treatment using trepanation combined with superficial radiotherapy (SRT-100) in our hospital, most of the boyâs keloids shrank and flattened. The affected foot returned to its normal appearance, and the boy could wear shoes normally. The boy did not complain of pain, numbness, or any other distinctive discomfort after completing the treatment. This suggested that the combination of trepanation and SRT-100 may be one of the options for treating hypertrophic keloids that cannot be treated by surgical excision
An appropriate ammonium: nitrate ratio promotes the growth of centipedegrass: insight from physiological and micromorphological analyses
Reasonable nitrogen fertilizer application is an important strategy to maintain optimal growth of grasslands, thereby enabling them to better fulfil their ecological functions while reducing environmental pollution caused by high nitrogen fertilizer production and application. Optimizing the ammonium (NH4+):nitrate (NO3-) ratio is a common approach for growth promotion in crops and vegetables, but research on this topic in grass plants has not received sufficient attention. Centipedegrass, which is widely used in landscaping and ecological protection, was used as the experimental material. Different NH4+:NO3- ratios (0: 100, 25:75, 50:50, 75:25, 100:0) were used as the experimental treatments under hydroponic conditions. By monitoring the physiological and morphological changes under each treatment, the appropriate NH4+:NO3- ratio for growth and its underlying mechanism were determined. As the proportion of ammonium increased, the growth showed a âbell-shapedâ response, with the maximum biomass and total carbon and nitrogen accumulation achieved with the NH4+:NO3- ratio of 50:50 treatment. Compared with the situation where nitrate was supplied alone, increasing the ammonium proportion increased the whole plant biomass by 93.2%, 139.7%, 59.0%, and 30.5%, the whole plant nitrogen accumulation by 44.9%, 94.6%, 32.8%, and 54.8%, and the whole plant carbon accumulation by 90.4%, 139.9%, 58.7%, and 26.6% in order. As a gateway for nitrogen input, the roots treated with an NH4+:NO3- ratio of 50:50 exhibited the highest ammonium and nitrate uptake rate, which may be related to the maximum total root length, root surface area, average root diameter, root volume, and largest root xylem vessel. As a gateway for carbon input, leaves treated with an NH4+:NO3- ratio of 50:50 exhibited the highest stomatal aperture, stomatal conductance, photosynthetic rate, transpiration rate, and photosynthetic products. The NH4+:NO3- ratio of 50:50 treatment had the largest stem xylem vessel area. This structure and force caused by transpiration may synergistically facilitate root-to-shoot nutrient translocation. Notably, the change in stomatal opening occurred in the early stage (4 hours) of the NH4+:NO3- ratio treatments, indicating that stomates are structures that are involved in the response to changes in the root NH4+:NO3- ratio. In summary, we recommend 50:50 as the appropriate NH4+:NO3- ratio for the growth of centipedegrass, which not only improves the nitrogen use efficiency but also enhances the carbon sequestration capacity
Antibiotics induce polarization of pleural macrophages to M2-like phenotype in patients with tuberculous pleuritis
Pleural macrophages play critical roles in pathogenesis of tuberculous pleuritis, but very little is known about their response to anti-tuberculosis antibiotics treatment. Here, we examined whether and how pleural macrophages change in phenotype, transcription and function following antibiotics treatment in patients with tuberculous pleuritis. Results show pro-inflammatory cytokines were down-regulated significantly post antibiotic treatment in the pleural effusions and pleural macrophages up-regulated markers characteristic of M2 macrophages such as CD163 and CD206. Differential expression analysis of transcriptomes from four paired samples before and after treatment identified 230 treatment-specific responsive genes in pleural macrophages. Functional analysis identified interferon-related pathway to be the most responsive genes and further confirmed macrophage polarization to M2-like phenotype. We further demonstrate that expression of a significant fraction of responsive genes was modulated directly by antibiotics in pleural macrophages in vitro. Our results conclude that pleural macrophages polarize from M1-like to M2-like phenotype within a mean of 3.5 days post antibiotics treatment, which is dependent on both pleural cytokine environment and direct modulatory effects of antibiotics. The treatment-specific genes could be used to study the roles of pleural macrophages in the pathogenesis of tuberculous pleuritis and to monitor the response to antibiotics treatment
Physics-informed Deep Diffusion MRI Reconstruction with Synthetic Data: Break Training Data Bottleneck in Artificial Intelligence
Diffusion magnetic resonance imaging (MRI) is the only imaging modality for
non-invasive movement detection of in vivo water molecules, with significant
clinical and research applications. Diffusion MRI (DWI) acquired by multi-shot
techniques can achieve higher resolution, better signal-to-noise ratio, and
lower geometric distortion than single-shot, but suffers from inter-shot
motion-induced artifacts. These artifacts cannot be removed prospectively,
leading to the absence of artifact-free training labels. Thus, the potential of
deep learning in multi-shot DWI reconstruction remains largely untapped. To
break the training data bottleneck, here, we propose a Physics-Informed Deep
DWI reconstruction method (PIDD) to synthesize high-quality paired training
data by leveraging the physical diffusion model (magnitude synthesis) and
inter-shot motion-induced phase model (motion phase synthesis). The network is
trained only once with 100,000 synthetic samples, achieving encouraging results
on multiple realistic in vivo data reconstructions. Advantages over
conventional methods include: (a) Better motion artifact suppression and
reconstruction stability; (b) Outstanding generalization to multi-scenario
reconstructions, including multi-resolution, multi-b-value,
multi-undersampling, multi-vendor, and multi-center; (c) Excellent clinical
adaptability to patients with verifications by seven experienced doctors
(p<0.001). In conclusion, PIDD presents a novel deep learning framework by
exploiting the power of MRI physics, providing a cost-effective and explainable
way to break the data bottleneck in deep learning medical imaging.Comment: 23 pages, 16 figure
Construction of a cross-species cell landscape at single-cell level.
Individual cells are basic units of life. Despite extensive efforts to characterize the cellular heterogeneity of different organisms, cross-species comparisons of landscape dynamics have not been achieved. Here, we applied single-cell RNA sequencing (scRNA-seq) to map organism-level cell landscapes at multiple life stages for mice, zebrafish and Drosophila. By integrating the comprehensive dataset of > 2.6 million single cells, we constructed a cross-species cell landscape and identified signatures and common pathways that changed throughout the life span. We identified structural inflammation and mitochondrial dysfunction as the most common hallmarks of organism aging, and found that pharmacological activation of mitochondrial metabolism alleviated aging phenotypes in mice. The cross-species cell landscape with other published datasets were stored in an integrated online portal-Cell Landscape. Our work provides a valuable resource for studying lineage development, maturation and aging
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