Cloudinids have long been considered the earliest biomineralizing metazoans, but their affinities have remained contentious and undetermined. Based on well-preserved ultrastructures of two taxa, we here propose new in...
Cloudinids have long been considered the earliest biomineralizing metazoans, but their affinities have remained contentious and undetermined. Based on well-preserved ultrastructures of two taxa, we here propose new interpretations regarding both their extent of original biomineralization and their phylogenetic affinity. One of these taxa is a new cloudinid from Mongolia, Zuunia chimidtsereni gen. et sp. nov., which exhibits key characteristics of submicrometric kerogenous lamellae, plastic tubewall deformation, and tube-wall delamination. Multiple carbonaceous lamellae are also discovered in Cloudina from Namibia and Paraguay, which we interpret to have originated from chitinous or collagenous fabrics. We deduce that these cloudinids were predominantly originally organic (chitinous or collagenous), and postmortem decay and taphonomic mineralization resulted in the formation of aragonite and/or calcite. Further, based on our ultrastructural characterization and other morphological similarities, we suggest that the cloudinids should most parsimoniously be assigned to annelids with originally organic tubes.
Purpose: The purpose of this study was to determine the risk factors associated with pneumonia, acute respiratory distress syndrome (ARDS), and clinical outcome among patients with novel coronavirus disease 2019 (COVI...
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Purpose: The purpose of this study was to determine the risk factors associated with pneumonia, acute respiratory distress syndrome (ARDS), and clinical outcome among patients with novel coronavirus disease 2019 (COVID-19). Methods: This was a cross-sectional multicenter clinical study. A total of 95 patients infected with COVID-19 were enrolled. The COVID-19 diagnostic standard was polymerase chain reaction detection of target genes of 2019 novel coronavirus (2019-nCoV). Clinical, laboratory, and radiologic results, as well as treatment outcome data, were obtained. ARDS was defined as an oxygenation index (arterial partial pressure of oxygen/fraction of inspired oxygen) <= 300 mm Hg. Findings: Multivariate analysis showed that older age (odds ratio [OR], 1.078;p = 0.008) and high body mass index (OR, 1.327;p = 0.024) were independent risk factors associated with patients with pneumonia. For patients with ARDS, multivariate analysis showed that only high systolic blood pressure (OR, 1.046;p = 0.025) and high lactate dehydrogenase level (OR, 1.010;p = 0.021) were independent risk factors associated with ARDS. A total of 70 patients underwent CT imaging repeatedly after treatment. Patients were divided in a disease exacerbation group (n = 19) and a disease relief group (n = 51). High body mass index (OR, 1.285;p = 0.017) and tobacco smoking (OR, 16.13;p = 0.032) were independent risk factors associated with disease exacerbation after treatment. (C) 2020 The Authors. Published by Elsevier Inc.
Flexible electronics have emerged as an exciting research area in recent years,serving as ideal interfaces bridging biological systems and conventional electronic *** electronics can not only collect physiological sig...
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Flexible electronics have emerged as an exciting research area in recent years,serving as ideal interfaces bridging biological systems and conventional electronic *** electronics can not only collect physiological signals for human health monitoring but also enrich our daily life with multifunctional smart materials and *** hydrogels(CHs)have become promising candidates for the fabrication of flexible electronics owing to their biocompatibility,adjustable mechanical flexibility,good conductivity,and multiple stimuli-responsive *** achieve on-demand mechanical properties such as stretchability,compressibility,and elasticity,the rational design of polymer networks via modulating chemical and physical intermolecular interactions is ***,the type of conductive components(eg,electron-conductive materials,ions)and the incorporation method also play an important role in the conductivity of ***-CHs usually possess excellent conductivity,while ion-CHs are generally transparent and can generate ion gradients within the hydrogel *** mini review focuses on the recent advances in the design of CHs,introducing various design strategies for electron-CHs and ion-CHs employed in flexible electronics and highlighting their versatile applications such as biosensors,batteries,supercapacitors,nanogenerators,actuators,touch panels,and displays.
In the process design and reuse of marine component products, there are a lot of heterogeneous models, causing the problem that the process knowledge and process design experience contained in them are difficult to ex...
In the process design and reuse of marine component products, there are a lot of heterogeneous models, causing the problem that the process knowledge and process design experience contained in them are difficult to express and reuse. Therefore, a process knowledge representation model for ship heterogeneous model is proposed in this paper. Firstly, the multi-element process knowledge graph is constructed, and the heterogeneous ship model is described in a unified way. Then, the multi-strategy ontology mapping method is applied, and the semantic expression between the process knowledge graph and the entity model is realized. Finally, by obtaining implicit semantics based on case-based reasoning and checking the similarity of the matching results, the case knowledge reuse is achieved, to achieve rapid design of the process. This method provides reliable technical support for the design of ship component assembly and welding process, greatly shortens the design cycle, and improves the working efficiency. In addition, taking the double-deck bottom segment of a ship as an example, the process knowledge map of the heterogeneous model is constructed to realize the rapid design of ship process, which shows that the method can effectively acquire the process knowledge in the design case and improve the efficiency and intelligence of knowledge reuse in the process design of the heterogeneous model of a ship.
Model-based definition (MBD) carries out a technological innovation for global manufacturing, application of MBD technology plays an important supporting in process design, product manufacturing and other development ...
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Model-based definition (MBD) carries out a technological innovation for global manufacturing, application of MBD technology plays an important supporting in process design, product manufacturing and other development activities, rapid creation of MBD models have become a key to reduce time and cost for enterprises. However, interactive dimensioning method has severely hampered the efficiency of MBD model creation. This paper mainly studies the dimensions intelligent marking method based on the predefined features to solve the rapid modeling problem of MBD model. Firstly, the expression model of dimensions metadata is established based on the feature identifier. Secondly, by establishing an association mechanism between the dimensions and the predefined feature, the "model-feature-dimensioning" association model is formed. Thirdly, through analysis of the dimensioning type, the intelligent dimensioning algorithm process is determined. Moreover, the completeness check of the dimensions is guaranteed during the marking process. Finally, taking the connecting rod and crankshaft of marine diesel as the research object, the effectiveness of this method is verified.
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