25 research outputs found
Detection of Carbon Monoxide Using Polymer-Carbon Composite Films
A carbon monoxide (CO) sensor was developed that can be incorporated into an existing sensing array architecture. The CO sensor is a low-power chemiresistor that operates at room temperature, and the sensor fabrication techniques are compatible with ceramic substrates. Sensors made from four different polymers were tested: poly (4-vinylpryridine), ethylene-propylene-diene-terpolymer, polyepichlorohydrin, and polyethylene oxide (PEO). The carbon black used for the composite films was Black Pearls 2000, a furnace black made by the Cabot Corporation. Polymers and carbon black were used as received. In fact, only two of these sensors showed a good response to CO. The poly (4-vinylpryridine) sensor is noisy, but it does respond to the CO above 200 ppm. The polyepichlorohydrin sensor is less noisy and shows good response down to 100 ppm
Using Electronic Noses to Detect Tumors During Neurosurgery
It has been proposed to develop special-purpose electronic noses and algorithms for processing the digitized outputs of the electronic noses for determining whether tissue exposed during neurosurgery is cancerous. At present, visual inspection by a surgeon is the only available intraoperative technique for detecting cancerous tissue. Implementation of the proposal would help to satisfy a desire, expressed by some neurosurgeons, for an intraoperative technique for determining whether all of a brain tumor has been removed. The electronic-nose technique could complement multimodal imaging techniques, which have also been proposed as means of detecting cancerous tissue. There are also other potential applications of the electronic-nose technique in general diagnosis of abnormal tissue. In preliminary experiments performed to assess the viability of the proposal, the problem of distinguishing between different types of cultured cells was substituted for the problem of distinguishing between normal and abnormal specimens of the same type of tissue. The figure presents data from one experiment, illustrating differences between patterns that could be used to distinguish between two types of cultured cancer cells. Further development can be expected to include studies directed toward answering questions concerning not only the possibility of distinguishing among various types of normal and abnormal tissue but also distinguishing between tissues of interest and other odorous substances that may be present in medical settings
Detection of Carbon Monoxide Using Polymer-Composite Films with a Porphyrin-Functionalized Polypyrrole
Post-fire air constituents that are of interest to NASA include CO and some acid gases (HCl and HCN). CO is an important analyte to be able to sense in human habitats since it is a marker for both prefire detection and post-fire cleanup. The need exists for a sensor that can be incorporated into an existing sensing array architecture. The CO sensor needs to be a low-power chemiresistor that operates at room temperature; the sensor fabrication techniques must be compatible with ceramic substrates. Early work on the JPL ElectronicNose indicated that some of the existing polymer-carbon black sensors might be suitable. In addition, the CO sensor based on polypyrrole functionalized with iron porphyrin was demonstrated to be a promising sensor that could meet the requirements. First, pyrrole was polymerized in a ferric chloride/iron porphyrin solution in methanol. The iron porphyrin is 5, 10, 15, 20-tetraphenyl-21H, 23Hporphine iron (III) chloride. This creates a polypyrrole that is functionalized with the porphyrin. After synthesis, the polymer is dried in an oven. Sensors were made from the functionalized polypyrrole by binding it with a small amount of polyethylene oxide (600 MW). This composite made films that were too resistive to be measured in the device. Subsequently, carbon black was added to the composite to bring the sensing film resistivity within a measurable range. A suspension was created in methanol using the functionalized polypyrrole (90% by weight), polyethylene oxide (600,000 MW, 5% by weight), and carbon black (5% by weight). The sensing films were then deposited, like the polymer-carbon black sensors. After deposition, the substrates were dried in a vacuum oven for four hours at 60 C. These sensors showed good response to CO at concentrations over 100 ppm. While the sensor is based on a functionalized pyrrole, the actual composite is more robust and flexible. A polymer binder was added to help keep the sensor material from delaminating from the electrodes, and carbon was added to improve the conductivity of the material
O Serviço de documentação textual e iconografia do Museu Paulista
The essay compares the curatorship's works realized during the decade of 1990 by the actual Department of Textual and Iconographical Documentation of Museu Paulista, responsible for the MP Fund / Permanent File (Fundo MP/Arquivo Permanente), hundreds of collections and textual funds and 50.000 iconography pieces, great part of which are gathered in photographic collections. It shows how the documentation work extrapolates the limits of SVDHICO in order to integrate itself with the group activities of the museum and with other research groups. It also points towards new work methodologies which allow to perform the curatorship in an integrated way with the interdisciplinary research and the culture diffusion.O artigo faz um balanço dos trabalhos de curadoria realizados durante a década de 1990 pelo atual Serviço de Documentação Textual e Iconografia do Museu Paulista, responsável pelo Fundo MP/Arquivo Permanente, centenas de coleções e fundos textuais e 50.000 peças de iconografia, grande parte delas reunidas em coleções fotográficas. Mostra como o trabalho de documentação extrapola os limites do SVDHICO para integrar-se com as atividades de conjunto do Museu e com outros grupos de pesquisa. Aponta também para novas metodologias de trabalho com imagens que permitem realizar a curadoria de forma integrada à pesquisa interdisciplinar e à difusão cultural
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Remediation of Thirdhand Tobacco Smoke with Ozone: Probing Deep Reservoirs in Carpets
We assessed the efficacy of ozonation as an indoor remediation strategy by evaluating how a carpet serves as a sink and long-term source of thirdhand tobacco smoke (THS) while protecting contaminants absorbed in deep reservoirs by scavenging ozone. Specimens from unused carpet that was exposed to smoke in the lab ("fresh THS") and contaminated carpets retrieved from smokers' homes ("aged THS") were treated with 1000 ppb ozone in bench-scale tests. Nicotine was partially removed from fresh THS specimens by volatilization and oxidation, but it was not significantly eliminated from aged THS samples. By contrast, most of the 24 polycyclic aromatic hydrocarbons detected in both samples were partially removed by ozone. One of the home-aged carpets was installed in an 18 m3 room-sized chamber, where its nicotine emission rate was 950 ng day-1 m-2. In a typical home, such daily emissions could amount to a non-negligible fraction of the nicotine released by smoking one cigarette. The operation of a commercial ozone generator for a total duration of 156 min, reaching concentrations up to 10,000 ppb, did not significantly reduce the carpet nicotine loading (26-122 mg m-2). Ozone reacted primarily with carpet fibers, rather than with THS, leading to short-term emissions of aldehydes and aerosol particles. Hence, by being absorbed deeply into carpet fibers, THS constituents can be partially shielded from ozonation
The EC Domains of Human Fibrinogen420Contain Calcium Binding Sites But Lack Polymerization Pockets
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2021 American College of Rheumatology Guideline for the Treatment of Rheumatoid Arthritis
ObjectiveTo develop updated guidelines for the pharmacologic management of rheumatoid arthritis.MethodsWe developed clinically relevant population, intervention, comparator, and outcomes (PICO) questions. After conducting a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to rate the certainty of evidence. A voting panel comprising clinicians and patients achieved consensus on the direction (for or against) and strength (strong or conditional) of recommendations.ResultsThe guideline addresses treatment with disease-modifying antirheumatic drugs (DMARDs), including conventional synthetic DMARDs, biologic DMARDs, and targeted synthetic DMARDs, use of glucocorticoids, and use of DMARDs in certain high-risk populations (i.e., those with liver disease, heart failure, lymphoproliferative disorders, previous serious infections, and nontuberculous mycobacterial lung disease). The guideline includes 44 recommendations (7 strong and 37 conditional).ConclusionThis clinical practice guideline is intended to serve as a tool to support clinician and patient decision-making. Recommendations are not prescriptive, and individual treatment decisions should be made through a shared decision-making process based on patients' values, goals, preferences, and comorbidities
2021 American College of Rheumatology Guideline for the Treatment of Rheumatoid Arthritis
Guidelines and recommendations developed and/or endorsed by the American College of Rheumatology (ACR) are intended to provide general guidance for commonly encountered clinical scenarios. The recommendations do not dictate the care for an individual patient. The ACR considers adherence to the recommendations described in this guideline to be voluntary, with the ultimate determination regarding their application to be made by the clinicians in light of each patient’s individual circumstances. Guidelines and recommendations are intended to promote beneficial or desirable outcomes but cannot guarantee any specific outcome. Guidelines and recommendations developed and endorsed by the ACR are subject to periodic revision as warranted by the evolution of medical knowledge, technology, and practice. ACR recommendations are not intended to dictate payment or insurance decisions, or drug formularies or other third-party analyses. Third parties that cite ACR guidelines should state that these recommendations are not meant for this purpose. These recommendations cannot adequately convey all uncertainties and nuances of patient care. The American College of Rheumatology is an independent, professional, medical and scientific society that does not guarantee, warrant, or endorse any commercial product or service. OBJECTIVE. To develop updated guidelines for the pharmacologic management of rheumatoid arthritis. METHODS. We developed clinically relevant population, intervention, comparator, and outcomes (PICO) questions. After conducting a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to rate the certainty of evidence. A voting panel comprising clinicians and patients achieved consensus on the direction (for or against) and strength (strong or conditional) of recommendations. RESULTS. The guideline addresses treatment with disease-modifying antirheumatic drugs (DMARDs), including conventional synthetic DMARDs, biologic DMARDs, and targeted synthetic DMARDs, use of glucocorticoids, and use of DMARDs in certain high-risk populations (i.e., those with liver disease, heart failure, lymphoproliferative disorders, previous serious infections, and nontuberculous mycobacterial lung disease). The guideline includes 44 recommendations (7 strong and 37 conditional). CONCLUSION. This clinical practice guideline is intended to serve as a tool to support clinician and patient decision-making. Recommendations are not prescriptive, and individual treatment decisions should be made through a shared decision-making process based on patients’ values, goals, preferences, and comorbidities
OMERACT Development of a Core Domain Set of Outcomes for Shared Decision-making Interventions
Objective. The Outcome Measures in Rheumatology (OMERACT) Shared Decision Making (SDM) Working Group aims to determine the core outcome domain set for measuring the effectiveness of SDM interventions in rheumatology trials. Methods. A white paper was developed to clarify the draft core domain set. It was then used to prepare for interviews to investigate reasons for lack of consensus on it and to suggest further improvements. Results. OMERACT scientists/clinicians (n = 13) and patients (n = 10) suggested limiting the core domain set to outcome domains, removing process domains, and clarifying remaining domains. Conclusion. A revised core domain set will undergo further consensus-building