138 research outputs found

    Eosinophilic Granulomatosis With Polyangiitis Diagnosed in an Elderly Female After the Second Dose of mRNA Vaccine Against COVID-19

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    Eosinophilic granulomatosis with polyangiitis is a type of medium and small-vessel vasculitis that is characterized by asthma, polyneuropathy, peripheral eosinophilia, rhinosinusitis, and other organ involvement, such as the lung and skin. Here, we present an interesting case of eosinophilic granulomatosis with polyangiitis after the mRNA-1273 (Moderna) vaccine against coronavirus disease 2019 (COVID-19). The patient presented with progressive weakness and paresthesia in the upper and lower extremities. She was found to have peripheral eosinophilia and elevated anti-myeloperoxidase antibodies. Nerve and muscle biopsies showed focal vasculitis with infiltration by eosinophils. The patient was started on steroids and a steroid-sparing agent shortly after that and had marked improvement of her symptoms

    A Study of Scrap Rubber Devulcanization and Incorporation of Devulcanized Rubber into Virgin Rubber Compound

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    In this era of rapid development and economic growth, waste management is of high concern for humans. According to statistics, a great amount of rubber waste materials are produced annually. The major amount of these waste rubber material comes from scrap tires. Only a few percent of the waste rubber materials are recycled and made into new products. Recycling of waste rubber has a certain problem: the crosslink structure of thermoset rubber. Due to the presence of three dimensional crosslink structures in rubber products, they cannot be reprocessed by application of heat, like we do for thermoplastic materials. In order to recycle and reuse the vulcanized rubber we have to find a way to cleave the crosslink bonds. This technique which can break down the crosslink bonds in the rubber is called devulcanization. Different devulcanization processes are utilizing heat, chemicals, ultrasound, and mechanical stresses in order to break down the crosslink structure of vulcanized rubber and convert the insoluble thermoset rubber into a soft and sticky material which can be processed and vulcanized again. Comparing various devulcanization processes, the thermo-mechanical devulcanization process which applies mechanical forces and heat to break down the crosslink network of rubber is very effective. One of the common ways to maintain the required shear stresses and mechanical forces to cleave and break down the crosslink structure of vulcanized rubber is utilizing the extrusion process. In this research, twin screw extruders are preferred due to their modular designs which enable us to adjust the different levels of shearing on the material. In order to facilitate the extrusion process supercritical carbon dioxide is used. Supercritical carbon dioxide diffuses into the rubber particles during the devulcanization process and facilitates the process by expanding and softening the rubber particles. In this research we have established a high throughput devulcanization process to produce devulcanized scrap tire rubber at an industrial scale. The effect of different process parameters on obtained devulcanized rubber properties, such as network structure, rheological properties, and physical and mechanical properties are studied. Results showed that in the range of our experiment design, the only effective parameter on crosslink density and Mooney viscosity of the devulcanized scrap tire is feed rate. Using Horikx theory, it was shown that the devulcanization mechanism for our scrap tire devulcanization process is a selective crosslink cleavage rather than a random chain scission. The obtained devulcanized rubber was then incorporated in a virgin tire rubber compound and the impact of devulcanized rubber utilization on tire compound performance was studied. Results showed that incorporation of devulcanized rubber into a tire tread compound up to 30 percent does not deteriorate the tire tread properties in a significant manner. Finally, a high throughput devulcanization process was established for scrap ethylene-diene-propylene (EDPM) rubber devulcanization. The effects of main process variables on the properties of the devulcanized EPDM rubber were studied. It was observed that crosslink density and Mooney viscosity of the devulcanized EPDM rubber are affected by the feed rate and screw speed in a significant manner.1 yea

    An Unusual Presentation of Immunoglobulin G4-Related Disease (IgG4-RD) Causing Subglottic Stenosis

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    Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory condition that is known to involve multiple organs and was first described as an entity in 2003. It is characterized by lesions with a dense lymphoplasmacytic infiltrate, IgG4-positive plasma cells, storiform fibrosis, and frequently elevated serum IgG4 levels. Organs that are commonly involved include the pancreas, biliary tree, salivary glands, periorbital tissues, kidneys, retroperitoneum, lungs, pleura, thyroid, aorta, and lymph nodes. Rarer manifestations of IgG4-RD include central nervous system (CNS) involvement, prostatitis, mastitis, midline destructive disease, and nasopharyngeal disease. In this report, we discuss an atypical case of a young woman with laryngeal subglottic involvement leading to stenosis and airway obstruction, which was ultimately successfully managed with systemic immunosuppression

    Investigating the impact of triangle and quadrangle mesh representations on AGV path planning for various indoor environments: With or without inflation

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    In a factory with different kinds of spatial atmosphere (warehouses, corridors, small or large workshops with varying sizes of obstacles and distribution patterns), the robot’s generated paths for navigation tasks mainly depend on the representation of that environment. Hence, finding the best representation for each particular environment is necessary to forge a compromise between length, safety, and complexity of path planning. This paper aims to scrutinize the impact of environment model representation on the performance of an automated guided vehicle (AGV). To do so, a multi-objective cost function, considering the length of the path, its complexity, and minimum distance to obstacles, is defined for a perfect circular robot. Unlike other similar studies, three types of representation, namely quadrangle, irregular triangle, and varying-size irregular triangle, are then utilized to model the environment while applying an inflation layer to the discretized view. Finally, a navigation scenario is tested for different cell decomposition methods and an inflation layer size. The obtained results indicate that a nearly constant coarse size triangular mesh is a good candidate for a fixed-size robot in a non-changing environment. Moreover, the varying size of the triangular mesh and grid cell representations are better choices for factories with changing plans and multi-robot sizes due to the effect of the inflation layer. Based on the definition of a metric, which is a criterion for quantifying the performance of path planning on a representation type, constant or variable size triangle shapes are the only and best candidate for discretization in about 59% of industrial environments. In other cases, both cell types, the square and the triangle, can together be the best representation

    Antitumor effects of a recombinant baculovirus displaying anti-HER2 scFv expressing Apoptin in HER2 positive SK-BR-3 breast cancer cells

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    Aim: Since HER2 targeted therapies have shown clinical benefit in breast cancer, in the present study recombinant baculovirus (BV) displaying anti-HER2 single-chain variable domain fragment (scFv) expressing Apoptin was generated. Methods: The binding specificity and surface display of anti-HER2 scFv were evaluated using enzyme-linked immunosorbent andassay (ELISA) and electron microscopy, respectively. The targeting properties and cytotoxic effect on breast cancer cells determined by fluorescence microscopy and MTT assays. Results: The results demonstrated that recombinant BV could specifically bind to HER2-overexpressing SK-BR-3 cells but not to the HER2 negative MCF-7 cells and reduced the viability of SK-BR-3 cells by expressing Apoptin. Conclusion: These results suggest that the antitumor effect of Apoptin in combination with HER2 targeting of this recombinant BV makes it a promising vector in targeted cancer therap

    Time dependent decomposition of ammonia borane for the controlled production of 2D hexagonal boron nitride.

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    Ammonia borane (AB) is among the most promising precursors for the large-scale synthesis of hexagonal boron nitride (h-BN) by chemical vapour deposition (CVD). Its non-toxic and non-flammable properties make AB particularly attractive for industry. AB decomposition under CVD conditions, however, is complex and hence has hindered tailored h-BN production and its exploitation. To overcome this challenge, we report in-depth decomposition studies of AB under industrially safe growth conditions. In situ mass spectrometry revealed a time and temperature-dependent release of a plethora of NxBy-containing species and, as a result, significant changes of the N:B ratio during h-BN synthesis. Such fluctuations strongly influence the formation and morphology of 2D h-BN. By means of in situ gas monitoring and regulating the precursor temperature over time we achieve uniform release of volatile chemical species over many hours for the first time, paving the way towards the controlled, industrially viable production of h-BN

    The Effect of Volume Fraction of Single-Walled Carbon Nanotubes on Natural Frequencies of Polymer Composite Cone-Shaped Shell Made from Poly(Methyl Methacrylate)

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    In this paper, the effect of volume fraction of single-walled carbon nanotubes on natural frequencies of polymer composite cone-shaped shells made from Poly(Methyl Methacrylate) (PMMA) is studied. In order to determine the characterization of materials reinforced with nanoparticles, the molecular dynamics and mixture rule has been used. The motion equations of composite shell based on the classical thin shells theory using Hamilton’s principle are obtained. Then, using the Ritz method, approximate analytical solution of the natural frequency is presented. Results indicate that the nanotubes have a noticeable effect on the natural frequencies

    Biosorption of uranium from aqueous solutions by nonliving biomass of marinealgae Cystoseira indica

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    Biosorption of heavy metals can be an effective process for the removal and recovery of heavy metal ions from aqueous solutions. In this paper uranium biosorption by protonated, Ca-pretreated and non-pretreated Cystoseira indica algae biomass was investigated in a batch system. The results of the kinetic studies showed that the sorption of uranium on protonated and non-pretreated biomass followed pseudo-second order kinetics. The effect of pH on the equilibrium uranium sorption capacity of Cystoseira indica exhibited that highest uptake occurred at pH 4 at a solution with 350 mg/l uranium concentration. At various initial uranium concentrations from 50 to 1000 mg/l, batch sorption equilibrium at 30\ubaC was reached within 3 hrs and the sorption isotherms were interpreted in terms of the Langmuir and Freundlich models. Equilibrium data fitted very well to Langmuir model for all studied forms of Cystoseira indica algae. The Freundlich isotherm cannot fit as well as the Langmuir model the equilibrium data of protonated and non-pretreated Cystoseira indica algae. The maximum uranium adsorption capacity on the Ca-pretreated, protonated and non-pretreated Cystoseira indica algae predicted by Langmuir isotherm at pH 4 and 30\ubaC was 454.5, 322.58 and 224.67 mg/g respectivel

    Utilizing logistic regression to compare risk factors in disease modeling with imbalanced data: a case study in vitamin D and cancer incidence

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    Imbalanced data, a common challenge encountered in statistical analyses of clinical trial datasets and disease modeling, refers to the scenario where one class significantly outnumbers the other in a binary classification problem. This imbalance can lead to biased model performance, favoring the majority class, and affecting the understanding of the relative importance of predictive variables. Despite its prevalence, the existing literature lacks comprehensive studies that elucidate methodologies to handle imbalanced data effectively. In this study, we discuss the binary logistic model and its limitations when dealing with imbalanced data, as model performance tends to be biased towards the majority class. We propose a novel approach to addressing imbalanced data and apply it to publicly available data from the VITAL trial, a large-scale clinical trial that examines the effects of vitamin D and Omega-3 fatty acid to investigate the relationship between vitamin D and cancer incidence in sub-populations based on race/ethnicity and demographic factors such as body mass index (BMI), age, and sex. Our results demonstrate a significant improvement in model performance after our undersampling method is applied to the data set with respect to cancer incidence prediction. Both epidemiological and laboratory studies have suggested that vitamin D may lower the occurrence and death rate of cancer, but inconsistent and conflicting findings have been reported due to the difficulty of conducting large-scale clinical trials. We also utilize logistic regression within each ethnic sub-population to determine the impact of demographic factors on cancer incidence, with a particular focus on the role of vitamin D. This study provides a framework for using classification models to understand relative variable importance when dealing with imbalanced data
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