175 research outputs found
Combined effect of ultrasound-guided percutaneous abdominal paracentesis drainage and ulinastatin on severe acute pancreatitis
Purpose: To study the clinical effect of a combination of ultrasound-guided percutaneous abdominal paracentesis drainage (APD) and ulinastatin on severe acute pancreatitis (AP).Methods: A total of 94 patients with severe AP in Intensive Care Unit, Jiaozhou Central Hospital, Qingdao, from December 2017 to December 2018 were selected as the research subjects. They were divided into control and study groups, with 47 patients in each group. Patients in the control group underwent laparotomy drainage, while patients in the study group underwent ultrasound-guidedpercutaneous APD. Patients in both groups received ulinastatin perfusion. Subsequently, clinical effectsand other relevant indicators were determined.Results: Overall response was significantly higher in the study group than in the control group (p < 0.05). The times taken for disappearance of postoperative symptoms, normalization of serum amylase level, and hospitalization were significantly shorter in the study group than in the control group (p < 0.05). For every indicator, the study group exhibited more benefits after than before treatment; however, post-treatment levels of blood glucose, hemodiastase and urinary amylase were better than those in the control group (p < 0.05). Incidence of postoperative complications was lower in the study group than in control group (p < 0.05).Conclusion: The combination of ultrasound-guided percutaneous APD with ulinastatin produces marked beneficial effects on severe AP patients. It facilitates the remission of adverse symptoms, and enhances normalization of indicator levels. Moreover, it displays low incidence of complications, better prognosis and recovery, and absence of post-operation infections
Perceptual Video Coding for Machines via Satisfied Machine Ratio Modeling
Video Coding for Machines (VCM) aims to compress visual signals for machine
analysis. However, existing methods only consider a few machines, neglecting
the majority. Moreover, the machine perceptual characteristics are not
effectively leveraged, leading to suboptimal compression efficiency. In this
paper, we introduce Satisfied Machine Ratio (SMR) to address these issues. SMR
statistically measures the quality of compressed images and videos for machines
by aggregating satisfaction scores from them. Each score is calculated based on
the difference in machine perceptions between original and compressed images.
Targeting image classification and object detection tasks, we build two
representative machine libraries for SMR annotation and construct a large-scale
SMR dataset to facilitate SMR studies. We then propose an SMR prediction model
based on the correlation between deep features differences and SMR.
Furthermore, we introduce an auxiliary task to increase the prediction accuracy
by predicting the SMR difference between two images in different quality
levels. Extensive experiments demonstrate that using the SMR models
significantly improves compression performance for VCM, and the SMR models
generalize well to unseen machines, traditional and neural codecs, and
datasets. In summary, SMR enables perceptual coding for machines and advances
VCM from specificity to generality. Code is available at
\url{https://github.com/ywwynm/SMR}
A genetic system for targeted mutations to disrupt and restore genes in the obligate bacterium, Ehrlichia chaffeensis
Citation: Wang, Y., Wei, L., Liu, H., Cheng, C., & Ganta, R. R. (2017). A genetic system for targeted mutations to disrupt and restore genes in the obligate bacterium, Ehrlichia chaffeensis. Scientific Reports, 7(1). https://doi.org/10.1038/s41598-017-16023-yObligate intracellular bacteria (obligates) belonging to Rickettsiales and Chlamydiales cause diseases in hundreds of millions of people worldwide and in many animal species. Lack of an efficient system for targeted mutagenesis in obligates remains a major impediment in understanding microbial pathogenesis. Challenges in creating targeted mutations may be attributed to essential nature of majority of the genes and intracellular replication dependence. Despite success in generating random mutations, a method that works well in creating mutations in specific genes of interest followed by complementation remains problematic for obligates and is a highly sought-after goal. We describe protocols to generate stable targeted mutations by allelic exchange in Ehrlichia chaffeensis, an obligate intracellular tick-borne bacterium responsible for human monocytic ehrlichiosis. Targeted mutations in E. chaffeensis were created to disrupt two genes, and also to restore one gene by another allelic exchange mutation leading to the restoration of transcription and protein expression from the inactivated gene and the recovered organisms also express mCherry, which distinguishes from the wild type. We expect that the methods developed are broadly applicable to other obligates, particularly to rickettsial pathogens, to routinely perform targeted mutations to enable studies focused on protein structure-function analyses, host-pathogen interactions and in developing vaccines
Simulating transport pathways of pelagic Sargassum from the Equatorial Atlantic into the Caribbean Sea
Since 2011, beach inundation of massive amounts of pelagic Sargassum algae has occurred around the Caribbean nations and islands. Previous studies have applied satellite ocean color to determine the origins of this phenomenon. These techniques, combined with complementary approaches, suggest that, rather than blooms originating in the Caribbean, they arrive from the Equatorial Atlantic. However, oceanographic context for these occurrences remains limited. Here, we present results from synthetic particle tracking experiments that characterize the interannual and seasonal dynamics of ocean currents and winds likely to influence the transport of Sargassum from the Equatorial Atlantic into the Caribbean Sea. Our findings suggest that Sargassum present in the western Equatorial Atlantic (west of longitude 50°W) has a high probability of entering the Caribbean Sea within a year’s time. Transport routes include the Guiana Current, North Brazil Current Rings, and the North Equatorial Current north of the North Brazil Current Retroflection. The amount of Sargassum following each route varies seasonally. This has important implications for the amount of time it takes Sargassum to reach the Caribbean Sea. By weighting particle transport predictions with Sargassum concentrations at release sites in the western Equatorial Atlantic, our simulations explain close to 90% of the annual variation in observed Sargassum abundance entering the Caribbean Sea. Additionally, results from our numerical experiments are in good agreement with observations of variability in the timing of Sargassum movement from the Equatorial Atlantic to the Caribbean, and observations of the spatial extent of Sargassum occurrence throughout the Caribbean. However, this work also highlights some areas of uncertainty that should be examined, in particular the effect of “windage” and other surface transport processes on the movement of Sargassum. Our results provide a useful launching point to predict Sargassum beaching events along the Caribbean islands well in advance of their occurrence and, more generally, to understand the movement ecology of a floating ecosystem that is essential habitat to numerous marine speciesNFP, GJG, LJG, EJ and JT acknowledge support from the NOAA Atlantic Oceanographic and Meteorological Laboratory. JT was also supported by NOAA/OceanWatch. CH and MW acknowledge support from NASA (NNX14AL98G, NNX16AR74G, and NNX17AE57G) and the William and Elsie Knight Endowed Fellowship. Funding for the development of HYCOM has been provided by the National Ocean Partnership Program and the Office of Naval ResearchS
A Neural-network Enhanced Video Coding Framework beyond ECM
In this paper, a hybrid video compression framework is proposed that serves
as a demonstrative showcase of deep learning-based approaches extending beyond
the confines of traditional coding methodologies. The proposed hybrid framework
is founded upon the Enhanced Compression Model (ECM), which is a further
enhancement of the Versatile Video Coding (VVC) standard. We have augmented the
latest ECM reference software with well-designed coding techniques, including
block partitioning, deep learning-based loop filter, and the activation of
block importance mapping (BIM) which was integrated but previously inactive
within ECM, further enhancing coding performance. Compared with ECM-10.0, our
method achieves 6.26, 13.33, and 12.33 BD-rate savings for the Y, U, and V
components under random access (RA) configuration, respectively
Nutrient content and stoichiometry of pelagic Sargassum reflects increasing nitrogen availability in the Atlantic Basin
© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Lapointe, B. E., Brewton, R. A., Herren, L. W., Wang, M., Hu, C., McGillicuddy, D. J., Lindell, S., Hernandez, F. J., & Morton, P. L. Nutrient content and stoichiometry of pelagic Sargassum reflects increasing nitrogen availability in the Atlantic Basin. Nature Communications, 12(1), (2021): 3060, https://doi.org/10.1038/s41467-021-23135-7.The pelagic brown macroalgae Sargassum spp. have grown for centuries in oligotrophic waters of the North Atlantic Ocean supported by natural nutrient sources, such as excretions from associated fishes and invertebrates, upwelling, and N2 fixation. Using a unique historical baseline, we show that since the 1980s the tissue %N of Sargassum spp. has increased by 35%, while %P has decreased by 44%, resulting in a 111% increase in the N:P ratio (13:1 to 28:1) and increased P limitation. The highest %N and δ15N values occurred in coastal waters influenced by N-rich terrestrial runoff, while lower C:N and C:P ratios occurred in winter and spring during peak river discharges. These findings suggest that increased N availability is supporting blooms of Sargassum and turning a critical nursery habitat into harmful algal blooms with catastrophic impacts on coastal ecosystems, economies, and human health.This work was funded by the US NASA Ocean Biology and Biogeochemistry Program (80NSSC20M0264, NNX16AR74G) and Ecological Forecast Program (NNX17AF57G), NOAA RESTORE Science Program (NA17NOS4510099), National Science Foundation (NSF-OCE 85–15492 and OCE 88–12055), “Save Our Seas” Specialty License Plate funds, granted through the Harbor Branch Oceanographic Institute Foundation, Ft. Pierce, FL, and a Red Wright Fellowship from the Bermuda Biological Station. A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by National Science Foundation Cooperative Agreement No. DMR-1644779 and the State of Florida. D.J.M. gratefully acknowledges the Holger W. Jannasch and Columbus O’Donnell Iselin Shared Chairs for Excellence in Oceanography, as well as support from the Mill Reef Fund
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