630 research outputs found

    Do Statin Medications Improve Periodontal Health and/or Outcomes? A Systematic Review

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141378/1/cap0194.pd

    Design of Direct and Indirect Wind Energy Harvest Systems

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    -Developing wind energy by using wind collector and electroactive materials are proposed and investigated in this article. Two systems will be considered to harvest energy: direct and indirect system. In direct system, wind induced drag force directly blow and vibrate the electroactive materials in the duct for generating electricity. Wind flowguided mechanism is designed to collect arbitrarily blowing wind in environment and guide the flow direction perpendicular to the cross section of the nozzle as much as possible so that more uniform velocity distribution profile is achieved. Nozzle accelerator is designed for the purpose of increasing wind velocity. Indirect system uses gear as additional mechanism to impact and vibrate the electroactive materials. Two types of indirect system integrating the wind collector with fan and roof turbine ventilator to impact and vibrate electroactive materials are proposed

    On the Significance and Predicted Functional Effects of the Crown-to-Implant Ratio: a Finite Element Study of Long-Term Implant Stability Using High-Resolution, Nonlinear Numerical Analysis

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    poster abstractBackground. As the use of short dental implants becomes increasingly popular, the effects of the crown-to-implant (C/I) ratio on stress and strain distributions remain controversial. Previous studies in literature disagree on results of interest and level of necessary technical detail. Purpose. The present study sought to evaluate the strain distribution and assess its functional implications in a single implant-supported crown with various C/I ratios placed in the maxillary molar region. Materials and Methods. A high-fidelity, nonlinear finite-element model was developed to simulate multiple clinical scenarios by laterally loading a set of single implants with various implant lengths and crown heights. Strain distribution and maximum equivalent strain were analyzed to evaluate the effects and significance of the crown height, implant length and C/I ratio. The consistency of predicted functional responses to resulting strain at the implant interface were analyzed by interface surface area. Results. Results were evaluated according to the mechanostat hypothesis to predict functional response to strain. Overloading and effects of strain concentrations were more prevalent with increasing C/I ratios. Overloading was predicted for all configurations to varying degrees, and increased with decreasing implant lengths. Fracture in trabecular bone was predicted for at least one C/I ratio and all implant lengths of 10 mm or less. Conclusions. Higher C/I ratios and lower implant lengths increase the biomechanical risks of overloading and fracture. Increasing C/I ratios augment the functional effects of other implant design factors, particularly implant interface features. Greater C/I ratios may be achieved with implant designs that induce less significant strain concentrations

    Analysis and Design of Roof Turbine Ventilator for Wind Energy Harvest

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    Harvesting energy using roof turbine ventilator and electroactive material has been investigated to verify its performance. Since electric power gained from a single piece of regular size is usually small, auxiliary device to vibrate multiple pieces of electroactive materials in order to harvest more power is required. In this paper, an attempt of using the developed nozzle wind collector associated with the popular roof turbine ventilator employed with gear mechanism to impact and vibrate a group of electroactive material to generate electricity is proposed. Number of blade and blade angle of the roof turbine ventilator are influential to the effectiveness of wind collection. Also, number of electroactive material employed on the turbine ventilator under the wind speed in environment eventually determines the efficiency of wind harvest. A simple model is derived to estimate the minimum driving force from the wind power that needs to overcome the inertia of the turbine ventilator mechanism and the electromechanical energy conversion of electroactive materials. Wind drag force is calculated by using CFD is assumed to provide such driving force. Various combinations of the blade angle, number of blade and electroactive material actuators are investigated in simulations. Optimum design concerning the environment wind resource and configuration of turbine ventilator is discussed. According to several case studies, a few of design trends is addressed for better efficiency of energy harvest. Since multiple electroactive materials are employed, circuitry design with parallel input sources is implemented to sum up the current and integrate the power

    Case Report: Neurally adjusted ventilatory assist as an effective rescue treatment for pulmonary interstitial emphysema in extremely low birth weight infants

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    Pulmonary interstitial emphysema (PIE) is a complication observed in extremely low birth weight (ELBW) infants on mechanical ventilation. Despite various proposed therapeutic interventions, the success rates have shown inconsistency. Neurally adjusted ventilatory assist (NAVA) stands out as a novel respiratory support mode, offering lower pressure and tidal volume in comparison to conventional ventilation methods. In this case report, we present five ELBW infants with refractory PIE who were transitioned to NAVA ventilation. Following the switch to NAVA, all cases of PIE gradually resolved. In contrast to traditional modes, NAVA provided respiratory support with significantly lower fraction of inspired oxygen, reduced peak inspiratory pressure, diminished mean airway pressure, and decreased tidal volume within 7 days of NAVA utilization (p = 0.042, 0.043, 0.043, and 0.042, respectively). Consequently, we propose that NAVA could serve as a valuable rescue treatment for ELBW infants with PIE

    Zero-shot Domain-sensitive Speech Recognition with Prompt-conditioning Fine-tuning

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    In this work, we propose a method to create domain-sensitive speech recognition models that utilize textual domain information by conditioning its generation on a given text prompt. This is accomplished by fine-tuning a pre-trained, end-to-end model (Whisper) to learn from demonstrations with prompt examples. We show that this ability can be generalized to different domains and even various prompt contexts, with our model gaining a Word Error Rate (WER) reduction of up to 33% on unseen datasets from various domains, such as medical conversation, air traffic control communication, and financial meetings. Considering the limited availability of audio-transcript pair data, we further extend our method to text-only fine-tuning to achieve domain sensitivity as well as domain adaptation. We demonstrate that our text-only fine-tuned model can also attend to various prompt contexts, with the model reaching the most WER reduction of 29% on the medical conversation dataset.Comment: F-T Liao and Y-C Chan contributed equall

    Atomically-thin metallic Si and Ge allotropes with high Fermi velocities

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    Silicon and germanium are the well-known materials used to manufacture electronic devices for the integrated circuits but they themselves are not considered as promising options for interconnecting the devices due to their semiconducting nature. We have discovered that both Si and Ge atoms can form unexpected metallic monolayer structures which are more stable than the extensively studied semimetallic silicene and germanene, respectively. More importantly, the newly discovered two-dimensional allotropes of Si and Ge have Fermi velocities superior to the Dirac fermions in graphene, indicating that the metal wires needed in the silicon-based integrated circuits can be made of Si atom itself without incompatibility, allowing for all-silicon-based integrated circuits.Comment: 10 pages, 3 figures, 1 tabl
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