299 research outputs found

    How accurate are TheraMon® microsensors at measuring intraoral wear-time? Recorded vs. actual wear times in five volunteers

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    BACKGROUND: The TheraMon® microsensor is the most recent device developed to measure the wear-time of removable appliances. The accuracy has not been validated intraorally. OBJECTIVES: To determine 1) if the TheraMon® microsensor accurately records time when fixed intraorally, and 2) the effect of the intraoral location on the recorded time. METHODS: A prospective pilot study, using a convenience sample, was carried out in a UK hospital orthodontic department. Five non-patient volunteers wore microsensors positioned palatal to an upper molar, and buccal to a lower molar for 7 days. Differences between actual amount of wear and the wear recorded by each device were calculated. Differences between sites were also examined. RESULTS: The mean daily wear-time recorded by the upper and lower microsensors combined was 23 hours (95% CI 22.6-23.4), which is a mean under-recording of 4% (CI 2.5-5.8%). The maximum daily under-reporting of wear times was 5.5 hours. Microsensors in the lower buccal sulcus recorded wear-times that were closer to actual wear-times. CONCLUSIONS: Assumptions made by the TheraMon® microsensors software lead to under-reporting of intraoral wear-time, particularly when placed palatally. These discrepancies could be significant in both clinical practice and research. Adjustment of the microsensor software parameters would improve accuracy, irrespective of the intraoral location

    Ferromagnetic models for cooperative behavior: Revisiting Universality in complex phenomena

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    Ferromagnetic models are harmonic oscillators in statistical mechanics. Beyond their original scope in tackling phase transition and symmetry breaking in theoretical physics, they are nowadays experiencing a renewal applicative interest as they capture the main features of disparate complex phenomena, whose quantitative investigation in the past were forbidden due to data lacking. After a streamlined introduction to these models, suitably embedded on random graphs, aim of the present paper is to show their importance in a plethora of widespread research fields, so to highlight the unifying framework reached by using statistical mechanics as a tool for their investigation. Specifically we will deal with examples stemmed from sociology, chemistry, cybernetics (electronics) and biology (immunology).Comment: Contributing to the proceedings of the Conference "Mathematical models and methods for Planet Heart", INdAM, Rome 201

    Carbon Capture and Storage

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    Emissions of carbon dioxide, the most important long-lived anthropogenic greenhouse gas, can be reduced by Carbon Capture and Storage (CCS). CCS involves the integration of four elements: CO 2 capture, compression of the CO2 from a gas to a liquid or a denser gas, transportation of pressurized CO 2 from the point of capture to the storage location, and isolation from the atmosphere by storage in deep underground rock formations. Considering full life-cycle emissions, CCS technology can reduce 65–85% of CO2 emissions from fossil fuel combustion from stationary sources, although greater reductions may be possible if low emission technologies are applied to activities beyond the plant boundary, such as fuel transportation. CCS is applicable to many stationary CO2 sources, including the power generation, refining, building materials, and the industrial sector. The recent emphasis on the use of CCS primarily to reduce emissions from coal-fired electricity production is too narrow a vision for CCS. Interest in CCS is growing rapidly around the world. Over the past decade there has been a remarkable increase in interest and investment in CCS. Whereas a decade ago, there was only one operating CCS project and little industry or government investment in R&D, and no financial incentives to promote CCS. In 2010, numerous projects of various sizes are active, including at least five large-scale full CCS projects. In 2015, it is expected that 15 large-scale, full-chain CCS projects will be running. Governments and industry have committed over USD 26 billion for R&D, scale-up and deployment. The technology for CCS is available today, but significant improvements are needed to support widespread deployment. Technology advances are needed primarily to reduce the cost of capture and increase confidence in storage security. Demonstration projects are needed to address issues of process integration between CO2 capture and product generation, for instance in power, cement and steel production, obtain cost and performance data, and for industry where capture is more mature to gain needed operational experience. Large-scale storage projects in saline aquifers are needed to address issues of site characterization and site selection, capacity assessment, risk management and monitoring. Successful experiences from five ongoing projects demonstrate that, at least on this limited scale, CCS can be safe and effective for reducing emissions. Five commercial-scale CCS projects are operational today with over 35 million tonnes of CO2 captured and stored since 1996. Observations from commercial storage projects, commercial enhanced oil recovery projects, engineered and natural analogues as well as theoretical considerations, models, and laboratory experiments suggest that appropriately selected and managed geological storage reservoirs are very likely to retain nearly all the injected CO2 for very long times, more than long enough to provide benefits for the intended purpose of CCS. Significant scale-up compared to existing CCS activities will be needed to achieve large reductions in CO2 emissions. A 5- to 10-fold scale-up in the size of individual projects is needed to capture and store emissions from a typical coal-fired power plant (500 to 1000 MW). A thousand fold scale-up in size of today’s CCS enterprise would be needed to reduce emissions by billions of tonnes per year (Gt/yr). The technical potential of CCS on a global level is promising, but on a regional level is differentiated. The primary technical limitation for CCS is storage capacity. Much more work needs to be done to realistically assess storage capacity on a worldwide, regional basis and sub-regional basis. Worldwide storage capacity estimation is improving but more experience is needed. Estimates for oil and gas reservoirs are about 1000 GtCO2, saline aquifers are estimated to have a capacity ranging from about 4000 to 23,000 GtCO2. However, there is still considerable debate about how much storage capacity actually exists, particularly in saline aquifers. Research, geological assessments and, most importantly, commercial-scale demonstration projects will be needed to improve confidence in capacity estimates. Costs and energy requirements for capture are high. Estimated costs for CCS vary widely, depending on the application (e.g. gas clean-up vs. electricity generation), the type of fuel, capture technology, and assumptions about the baseline technology. For example, with today’s technology, CCS would increase cost of generating electricity by 50–100%. In this case, capital costs and parasitic energy requirements of 15–30% are the major cost drivers. Research is underway to lower costs and energy requirements. Early demonstration projects are likely to cost more. The combination of high cost and low or absent incentives for large-scale deployment are a major factor limiting the widespread use of CCS. Due to high costs, CCS will not take place without strong incentives to limit CO2 emissions. Certainty about the policy and regulatory regimes will be crucial for obtaining access to capital to build these multi-billion dollar projects. Environmental risks of CCS appear manageable, but regulations are needed. Regulation needs to ensure due diligence over the lifecycle of the project, but should, most importantly, also govern site selection, operating guidelines, monitoring and closure of a storage facility. Experience so far has shown that local resistance to CO2 storage projects may appear and can lead to cancellation of planned CCS projects. Inhabitants of the areas around geological storage sites often have concerns about the safety and effectiveness of CCS. More CCS projects are needed to establish a convincing safety record. Early engagement of communities in project design and site selection as well as credible communication can help ease resistance. Environmental organisations sometimes see CCS as a distraction from a sustainable energy future. Social, economic, policy and political factors may limit deployment of CCS if not adequately addressed. Critical issues include ownership of underground pore space (primarily an issue in the US); long-term liability and stewardship; GHG accounting approaches and ve rification; and regulatory oversight regimes. Governments and the private sector are making significant progress on all of these issues. Government support to lower barriers for early deployments is needed to encourage private sector adoption. Developing countries will need support for technology access, lowering the cost of CCS, developing workforce capacity and training regulators for permitting, monitoring and oversight. CCS combined with biomass can lead to negative emissions . Such technologies are likely to be needed to achieve atmospheric stabilization of CO2 and may provide an additional incentive for CCS adoption

    A New Relativistic High Temperature Bose-Einstein Condensation

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    We discuss the properties of an ideal relativistic gas of events possessing Bose-Einstein statistics. We find that the mass spectrum of such a system is bounded by μm2M/μK,\mu \leq m\leq 2M/\mu _K, where μ\mu is the usual chemical potential, MM is an intrinsic dimensional scale parameter for the motion of an event in space-time, and μK\mu _K is an additional mass potential of the ensemble. For the system including both particles and antiparticles, with nonzero chemical potential μ,\mu , the mass spectrum is shown to be bounded by μm2M/μK,|\mu |\leq m\leq 2M/\mu _K, and a special type of high-temperature Bose-Einstein condensation can occur. We study this Bose-Einstein condensation, and show that it corresponds to a phase transition from the sector of continuous relativistic mass distributions to a sector in which the boson mass distribution becomes sharp at a definite mass M/μK.M/\mu _K. This phenomenon provides a mechanism for the mass distribution of the particles to be sharp at some definite value.Comment: Latex, 22 page

    Implementation of a pharmacogenomics consult service to support the INGENIOUS trial

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    Hospital systems increasingly utilize pharmacogenomic testing to inform clinical prescribing. Successful implementation efforts have been modeled at many academic centers. In contrast, this report provides insights into the formation of a pharmacogenomics consultation service at a safety-net hospital, which predominantly serves low-income, uninsured, and vulnerable populations. The report describes the INdiana GENomics Implementation: an Opportunity for the UnderServed (INGENIOUS) trial and addresses concerns of adjudication, credentialing, and funding

    Nanoscale waveguiding methods

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    While 32 nm lithography technology is on the horizon for integrated circuit (IC) fabrication, matching the pace for miniaturization with optics has been hampered by the diffraction limit. However, development of nanoscale components and guiding methods is burgeoning through advances in fabrication techniques and materials processing. As waveguiding presents the fundamental issue and cornerstone for ultra-high density photonic ICs, we examine the current state of methods in the field. Namely, plasmonic, metal slot and negative dielectric based waveguides as well as a few sub-micrometer techniques such as nanoribbons, high-index contrast and photonic crystals waveguides are investigated in terms of construction, transmission, and limitations. Furthermore, we discuss in detail quantum dot (QD) arrays as a gain-enabled and flexible means to transmit energy through straight paths and sharp bends. Modeling, fabrication and test results are provided and show that the QD waveguide may be effective as an alternate means to transfer light on sub-diffraction dimensions

    The delivery of personalised, precision medicines via synthetic proteins

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    Introduction: The design of advanced drug delivery systems based on synthetic and su-pramolecular chemistry has been very successful. Liposomal doxorubicin (Caelyx®), and liposomal daunorubicin (DaunoXome®), estradiol topical emulsion (EstrasorbTM) as well as soluble or erodible polymer systems such as pegaspargase (Oncaspar®) or goserelin acetate (Zoladex®) represent considerable achievements. The Problem: As deliverables have evolved from low molecular weight drugs to biologics (currently representing approximately 30% of the market), so too have the demands made of advanced drug delivery technology. In parallel, the field of membrane trafficking (and endocytosis) has also matured. The trafficking of specific receptors i.e. material to be recycled or destroyed, as well as the trafficking of protein toxins has been well characterized. This, in conjunction with an ability to engineer synthetic, recombinant proteins provides several possibilities. The Solution: The first is using recombinant proteins as drugs i.e. denileukin diftitox (Ontak®) or agalsidase beta (Fabrazyme®). The second is the opportunity to use protein toxin architecture to reach targets that are not normally accessible. This may be achieved by grafting regulatory domains from multiple species to form synthetic proteins, engineered to do multiple jobs. Examples include access to the nucleocytosolic compartment. Herein the use of synthetic proteins for drug delivery has been reviewed

    Role of genetic testing for inherited prostate cancer risk: Philadelphia prostate cancer consensus conference 2017

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    Purpose: Guidelines are limited for genetic testing for prostate cancer (PCA). The goal of this conference was to develop an expert consensus-dri
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