181 research outputs found

    The theory analysis and design for large parameter weak signal detector based on bistable stochastic resonance

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    Volume 3 Issue 11 (November 2015

    Provenance in Data Interoperability for Multi-Sensor Intercomparison

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    As our inventory of Earth science data sets grows, the ability to compare, merge and fuse multiple datasets grows in importance. This requires a deeper data interoperability than we have now. Efforts such as Open Geospatial Consortium and OPeNDAP (Open-source Project for a Network Data Access Protocol) have broken down format barriers to interoperability; the next challenge is the semantic aspects of the data. Consider the issues when satellite data are merged, cross-calibrated, validated, inter-compared and fused. We must match up data sets that are related, yet different in significant ways: the phenomenon being measured, measurement technique, location in space-time or quality of the measurements. If subtle distinctions between similar measurements are not clear to the user, results can be meaningless or lead to an incorrect interpretation of the data. Most of these distinctions trace to how the data came to be: sensors, processing and quality assessment. For example, monthly averages of satellite-based aerosol measurements often show significant discrepancies, which might be due to differences in spatio- temporal aggregation, sampling issues, sensor biases, algorithm differences or calibration issues. Provenance information must be captured in a semantic framework that allows data inter-use tools to incorporate it and aid in the intervention of comparison or merged products. Semantic web technology allows us to encode our knowledge of measurement characteristics, phenomena measured, space-time representation, and data quality attributes in a well-structured, machine-readable ontology and rulesets. An analysis tool can use this knowledge to show users the provenance-related distrintions between two variables, advising on options for further data processing and analysis. An additional problem for workflows distributed across heterogeneous systems is retrieval and transport of provenance. Provenance may be either embedded within the data payload, or transmitted from server to client in an out-of-band mechanism. The out of band mechanism is more flexible in the richness of provenance information that can be accomodated, but it relies on a persistent framework and can be difficult for legacy clients to use. We are prototyping the embedded model, incorporating provenance within metadata objects in the data payload. Thus, it always remains with the data. The downside is a limit to the size of provenance metadata that we can include, an issue that will eventually need resolution to encompass the richness of provenance information required for daata intercomparison and merging

    Combination of thymosin α1 with conventional therapy improves APC and IL-1R1 levels in children with severe pneumonia

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    Purpose: To investigate the effect of a combination of thymosin α1 with  conventional regimen on APC and IL-1R1 levels in children with severe pneumonia, and to provide a reference for its clinical treatment.Methods: A total of 96 children with severe pneumonia over a period of two years were divided into control and observation groups (48 cases per  group) by random number table method. The patients consisted of 46 males and 50 females within the age range of 0.1 - 6 years (mean age = 3.0 ± 1.2 years), and mean duration of 13.4 ± 2.2 days). Their acute physiology and chronic health evaluation II (APACHE II) was 20.3 ± 3.2 points. Patients in the control group were placed on conventional treatment programs, while those in the observation group, in addition to the  conventional treatments, received thymosin α1 (subcutaneous injection of thymosin α1 at a dose of 1.5 mg per injection) twice daily for the first 3 days, then once daily until the 7th day, after which the adverse reactions were observed and treated. Pulmonary function indices, and levels of APC, and IL-1R1 were also determined in the patients’ sera before and after the treatment regime.Results: The clinical efficacy of the observation group was significantly better (p < 0.05) than that of control. There were no significant differences (p > 0.05) in the indices of pulmonary function (maximal inspiratory and expiratory pressure, and peak expiratory flow) between the two groups before treatment. However, after treatment they were significantly higher (p < 0.05) in the observation group than in control. There were no significant differences (p > 0.05) in APC and IL-1R1 levels between the two groups before treatment, but after treatment, while the level of APC in the observation group was significantly increased (p < 0.05), the IL-1R1 level was significantly decreased (p < 0.05), when compared to the control group. Both groups showed no obvious adverse reactions during the treatmentregime.Conclusion: Combining thymosin α1 with routine treatment in the  management of children with severe pneumonia can significantly alleviate the symptoms of patients, greatly stimulate recovery of pulmonary function, improve APC and IL-1R1 levels, and prevent inflammation.Keywords: Pneumonia, Thymosin α1, Routine treatment, Inflammatory factors, Pulmonary functio

    Activation of Cyclooxygenase-2 by ATF4 During Endoplasmic Reticulum Stress Regulates Kidney Podocyte Autophagy Induced by Lupus Nephritis

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    Background/Aims: Autophagy plays an essential role in lupus nephritis (LN)-induced kidney injury, although the mechanism of action remains obscure. We investigated the role of cyclooxygenase-2 (COX-2) and the ATF4 endoplasmic reticulum (ER) stress pathway in LN-induced podocyte autophagy. Methods: We evaluated podocyte autophagy in a mouse model of LN. Protein levels of COX-2 and ATF4, and markers of autophagy, were evaluated by immunofluorescence and western blotting. To evaluate apoptosis, levels of PGE2 were measured by enzyme-linked immunosorbent assay. Results: LN induced kidney damage and dysfunction, which was associated with podocyte autophagy. COX-2 and the ATF4 ER stress pathway were induced by LN in cultured podocytes. Inhibition of COX-2 inhibited LN-induced autophagy in podocytes. In addition, blocking ER stress with 4-phenylbutyrate or RNAi partially counteracted COX-2 overexpression and LN-induced autophagy, suggesting that ER stress is required for LN-induced kidney autophagy. Furthermore, LN activated ATF4 and induced its nuclear translocation. Knockdown of ATF4 inhibited LN-induced COX-2 overexpression. Conclusions: Our study suggests a novel molecular mechanism by which COX2 overexpression, induced by the ATF4 ER stress pathway, contributes to LN-induced kidney autophagy and injury. These data demonstrate that COX-2 may be a potential therapeutic target against LN-induced nephropathy

    Evolution of free radicals in ultra-high molecular weight polyethylene irradiated by an electron beam during accelerated aging process

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    Irradiated medical ultra-high molecular-weight polyethylene (UHMWPE) must be validated through accelerated aging tests to meet the requirements for implantation into the human body. However, the free radical evolution mechanism of UHMWPE during accelerated aging remains obscure. We systematically analyzed the effectiveness of existing accelerated aging methods from the perspective of free radicals. The changes in the concentration and composition of the free radicals present in electron-beam-irradiated crosslinked UHMWPE during accelerated aging were evaluated using electron paramagnetic resonance spectroscopy. The evolution mechanisms of the free radicals during this process were analyzed; in addition, the mechanisms occurring in room-temperature air and under a 70 ℃ nitrogen atmosphere were analyzed and compared. The results revealed that accelerated aging evaluation methods had significant limitations. The evolution mechanism of the free radicals present on the surface of irradiated crosslinked UHMWPE as well as inside it in room-temperature air were significantly different from that observed in the accelerated aging environment. In addition, the generation rate and oxidation degree of the oxygen-induced free radicals in the two environments are different

    USNet: underwater image superpixel segmentation via multi-scale water-net

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    Underwater images commonly suffer from a variety of quality degradations, such as color casts, low contrast, blurring details, and limited visibility. Existing superpixel segmentation algorithms face challenges in achieving superior performance when directly applied to underwater images with quality degradation. In this paper, to alleviate the limitations of superpixel segmentation when applied to underwater scenes, we propose the first underwater superpixel segmentation network (USNet), specifically designed according to the intrinsic characteristics of underwater images. Considering the quality degradation, we propose a multi-scale water-net module (MWM) aimed at enhancing the quality of underwater images before superpixel segmentation. The degradation-aware attention (DA) mechanism is then created and incorporated into MWM to solve light scattering and absorption, which can decrease object visibility and cause blurred edges. By effectively directing the network to prioritize locations that exhibit a considerable decrease in quality, this method enhances the visibility of those specific areas. Additionally, we extract the deep spatial features using the coordinate attention method. Finally, these features are fused with the shallow spatial information using the dynamic spatiality embedding module to embed comprehensive spatial features. Training and testing were conducted on the SUIM dataset, the underwater change detection dataset, and UIEB dataset. Experimental results show that our method achieves the best scores in terms of achievable segmentation accuracy, undersegmentation error, and boundary recall evaluation metrics compared to other methods. Both quantitative and qualitative evaluations demonstrate that our method can handle complicated underwater scenes and outperform existing state-of-the-art segmentation methods

    Activation of MET signaling by HDAC6 offers a rationale for a novel ricolinostat and crizotinib combinatorial therapeutic strategy in diffuse large B‐cell lymphoma

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    Some histone deacetylases (HDACs) promote tumor cell growth and pan‐ or selective HDAC inhibitors are active in some cancers; however, the pivotal HDAC enzyme and its functions in human diffuse large B‐cell lymphoma (DLBCL) remain largely unknown. Using NanoString nCounter assays, we profiled HDAC mRNA expression and identified HDAC6 as an upregulated HDAC family member in DLBCL tissue samples. We then found that HDAC6 plays an oncogenic role in DLBCL, as evidenced by its promotion of cell proliferation in vitro and tumor xenograft growth in vivo. Mechanistically, the interaction between HDAC6 and HR23B downregulated HR23B expression, thereby reducing the levels of casitas B‐lineage lymphoma (c‐Cbl), an E3 ubiquitin ligase for hepatocyte growth factor receptor (MET), which resulted in the inhibition of MET ubiquitination‐dependent degradation. In addition, enhanced HDAC6 expression and decreased HR23B expression were correlated with poor overall survival rates among patients with DLBCL. Taken together, these results establish an HDAC6–HR23B–MET axis and indicate that HDAC6 is a potent promoter of lymphomagenesis in DLBCL. Thus, a therapeutic strategy based on HDAC6 inhibitors in combination with MET inhibitors is promising. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146400/1/path5108_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146400/2/path5108.pd

    Inducing drop to bubble transformation via resonance in ultrasound

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    Bubble formation plays an important role in industries concerned with mineral flotation, food, cosmetics, and materials, which requires additional energy to produce the liquid–gas interfaces. A naturally observed fact is, owing to the effect of surface tension, a bubble film tends to retract to reduce its surface area. Here we show a “reverse” phenomenon whereby a drop is transformed into a bubble using acoustic levitation via acoustic resonance. Once the volume of the cavity encapsulated by the buckled film reaches a critical value V*, resonance occurs and an abrupt inflation is triggered, leading to the formation of a closed bubble. Experiments and simulations both reveal that V* decreases with increasing acoustic frequency, which agrees well with acoustic resonance theory. The results afford enlightening insights into acoustic resonance and highlight its role in manipulating buckled fluid–fluid interfaces, providing a reference for fabricating unique core–shell-like materials
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