330 research outputs found

    An Investigation of Modeing Behaviors in Function Structure Modeling With Respect to Chaining Methods

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    The systematic engineering design process equips designers with tools and methods necessary to understand and solve a given design problem. Function decomposition is one such tool that allows designers to decompose the given problem into sub-problems which may be easier to address. Research on Function modeling, specifically Function Structure models, has focused on improving model construction techniques and using the Function Structure models to support concept generation. Additionally, Function Structure models have also been traditionally used as individual design tools; however, most other conceptual design tools are used in a collaborative setting (e.g. gallery sketching, method 3-6-5, etc.). This research investigates the use of Function Structure models as a collaborative tool by using seed models constructed using three different chaining methods (forward chaining, backward chaining, and nucleation) identified in a pilot protocol study. These seed models were intended to represent a partially completed model created by one designer, which was then delivered to the next designer for completion. A designer study and a protocol study were conducted to identify differences between the final Function Structure models generated using different seed models, based on the percent increase in the number of functions and flows, change in model complexity, and a rubric based evaluation of the model. Results show that using a nucleation seed model yield a higher increase in function and flows, as well as a larger change in model complexity. Analysis of the rubric based model evaluation shows that the presence of the seed model improves the evaluation scores, however, the type of chaining method used does not impact the final score. These results suggest that teaching of Function Structure models should include explicit identification of the different chaining methods, and recommends nucleation as the chaining method of choice. Moreover, future research areas are identified with respect to further comparison of chaining methods, as well as investigation of behavioral patterns in the modeling activity

    MINI-COG PERFORMANCE: A NOVEL MARKER OF RISK AMONG PATIENTS HOSPITALIZED FOR HEART FAILURE

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    Neo Left Main Channel Creation Using Double Stenting Alongside a Sapien 3 Aortic Valve Bioprosthesis for Left Main Coronary Obstruction Following Valve-in-Valve Transcatheter Aortic Valve Replacement: A Case Report With Review of Literature

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    Transcatheter aortic valve replacement in the setting of failed surgical bioprosthesis (valve-in-valve) is a valuable option for patients with bioprosthetic aortic stenosis or regurgitation who are deemed high risk for repeat open heart surgery. Although the procedure is successful with proper preprocedural assessment, instances of left main (LM) coronary artery ostium obstruction have been documented. We present a case of LM coronary obstruction in the immediate postoperative period following implantation of a 20-mm Edwards Sapien 3 valve inside the degenerated 21-mm Mitroflow bioprosthesis stenosis, which was treated with double stenting alongside the Edwards Sapien 3 valve creating a channel (“neo left main”) that extended from mid-LM to the upper margin of the Edwards Sapien 3 valve. Although valve-in-valve in a Mitroflow degenerated bioprosthesis is a relatively safe procedure, 2 or more stents may be necessary to scaffold a channel to the coronary arteries between Edwards Sapien 3 prosthesis and aorta in the event of a coronary obstruction

    Primary pleuropulmonary synovial sarcoma with brain metastases in a paediatric patient: an unusual presentation

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      Primary lung neoplasms are rare in children. The most common primary lung malignancies in children are pleuropulmonary blastoma and carcinoid tumour. Synovial sarcoma (SS) accounts for approximately 1% of all childhood malignancies. In absolute terms, the SS of the lungs and pleura are extremely rare and pose a diagnostic difficulty. Soft tissue sarcomas usually have a high potential for metastases, however, metastasis to the brain is rare, even in widely disseminated disease, and it has been described only in 3 case reports previously. Primary pleuropulmonary SS with brain metastases is even rarer. Here we present a case of an 11-year-old boy who presented with respiratory complaints, viz. fever and cough for 20 days. Initial impression was lung abscess, however, on histopathological, immunohistochemical and molecular study, the disorder was diagnosed as synovial sarcoma. After a week from the first consult, the child developed neurological symptoms, viz., an episode of convulsion and gradually worsening power of the lower limb. Computed tomography scan and Magnetic Resonance Spectroscopy was suggestive of brain metastases. Given the rarity of primary lung neoplasms in children, clinical detection remains a challenge. Delayed diagnoses are common as respiratory symptoms may be attributed to inflammatory or infective processes. Primary pleuropulmonary synovial sarcoma is a rare tumour and it is not known to commonly metastasise to the brain. Though rare, primary pleuropulmonary SS should be considered an important differential among peadiatric primary lung neoplasms due to its potential for curability if detected early, and more aggressive metastatic pattern, e.g. brain metastases making early detection imperative.

    Astrocyte Elevated Gene-1 (AEG-1) Deletion Selectively Enhances the Antinociceptive Effects of Morphine

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    Background: Opioids are a class of drugs that are utilized in clinical settings to alleviate acute and chronic pain, but can often lead to development of tolerance, addiction and overdose following prolonged usage. Opioids such as morphine function by activating endogenous µ opioid receptors, which are located in various tissues throughout the body. Astrocyte Elevated Gene-1 (AEG-1) is a multifunctional protein that regulates inflammation, myeloid cell activity and lipid metabolism. Studies have shown interactions and overlaps in cellular signaling between the inflammatory/immune responses and the endogenous opioid system which could suggest a role for AEG-1 in opioids effects. Our goal is to investigate the role of AEG-1 in morphine mediated pharmacological effects including analgesia. Methods: Adult AEG-1 global knockout (KO) and wild-type (WT) male and female mice (C57BL/6J background) were utilized to assess morphine-induced thermal antinociception (The tail immersion assay test), hyperlocomotion, gastrointestinal (GI) transit inhibition, and tolerance. GI transit was assessed via charcoal transit assay. Locomotor boxes were used to assess spontaneous activity in mice. Results: AEG-1 KO mice displayed increased thermal antinociception following acute and repeated morphine administration compared to their WT counterparts. Pretreatment with naloxone blocked the enhancement of morphine thermal antinociception in AEG-1 KO mice. In addition, chronic morphine treated AEG-1 KO mice displayed reduced morphine tolerance development compared to their WT counterparts. No significant differences in morphine-induced hyperlocomotion or GI transit inhibition were observed between AEG-1 KO and WT mice. Conclusions: Our data suggest that AEG-1 deletion enhances the antinociceptive effects of morphine and reduces tolerance to chronic morphine treatment. However, AEG-1 deletion does not impact morphine-induced locomotor activity of GI transit inhibition. Overall, our results suggest that AEG-1 may function as a modulator of the endogenous opioid system.https://scholarscompass.vcu.edu/uresposters/1413/thumbnail.jp

    Enhanced Anticancer Activity of Gemcitabine in Combination with Noscapine via Antiangiogenic and Apoptotic Pathway against Non-Small Cell Lung Cancer

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    BACKGROUND:The aim of this investigation was to evaluate the anticancer activity of Noscapine (Nos) and Gemcitabine (Gem) combination (NGC) against non-small cell lung cancer (NSCLC) and to elucidate the underlying mechanism of action. METHODS:Isobolographic method was used to calculate combination index values from cytotoxicity data. In vitro antiangiogenic and apoptotic activity of Nos, Gem and NGC was evaluated. For in vivo studies, female athymic Nu/nu mice were xenografted with H460 tumors and the efficacy of Nos, Gem, or NGC was determined. Protein expressions by immunohistochemical staining were evaluated in harvested tumor tissues. RESULTS:The CI values (<0.59) were suggestive of synergistic behavior between Nos and Gem. NGC treatment showed significantly inhibited tube formation and increased percentage of apoptotic cells. NGC, Gem and Nos treatment reduced tumor volume by 82.9±4.5 percent, 39.4±5.8 percent and 34.2±5.7 percent respectively. Specifically, NGC treatment decreased expression cell survival proteins; VEGF, CD31 staining and microvessel density and enhanced DNA fragmentation and cleaved caspase 3 levels compared to single agent treated and control groups. CONCLUSION:Nos potentiated the anticancer activity of Gem in an additive to synergistic manner against lung cancer via antiangiogenic and apoptotic pathways. These findings suggest potential benefit for use of NGC chemotherapy for treatment of lung cancer

    Testing in Engineering Design: What are we teaching

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    Although testing is critical in industries, the general approaches of testing in engineering design are under-represented in academia. This research investigates the current state of testing based on design textbooks. The findings suggest there is no clear definition of testing. Testing appears in different design stages with adjacent concepts such as prototyping, experimentation, verification, and validation. The processes of testing and its role within engineering design are ambiguous. Recommendations to design educators are provided, and the limitations of the study are discussed
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