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Enhancing Cellular Uptake of Magnetic Nanoparticles for Cancer Therapy via Nanoparticle Engineering & Sonoporation
Get PDFMagnetic induction heating of iron oxide nanoparticles has been proposed as a method for noninvasive cancer treatment without the side effects of chemotherapy and ionizing radiation. At Kettering University we propose to improve the uptake of nanoparticles by cells through the use of nanoparticle engineering and ultrasonic fields
Evaluating the effect of four different pointing device designs on upper extremity posture and muscle activity during mousing tasks
No full textThe goal of this study was to evaluate the effect of different types of computer pointing devices and placements on posture and muscle activity of the hand and arm. A repeated measures laboratory study with 12 adults (6 females, 6 males) was conducted. Participants completed two mouse-intensive tasks while using a conventional mouse, a trackball, a stand-alone touchpad, and a rollermouse. A motion analysis system and an electromyography system monitored right upper extremity postures and muscle activity, respectively. The rollermouse condition was associated with a more neutral hand posture (lower inter-fingertip spread and greater finger flexion) along with significantly lower forearm extensor muscle activity. The touchpad and rollermouse, which were centrally located, were associated with significantly more neutral shoulder postures, reduced ulnar deviation, and lower forearm extensor muscle activities than other types of pointing devices. Users reported the most difficulty using the trackball and touchpad. Rollermouse was not more difficult to use than any other devices. These results show that computer pointing device design and location elicit significantly different postures and forearm muscle activities during use, especially for the hand posture metrics
Analysis of a finite-buffer bulk-service queue under Markovian arrival process with batch-size-dependent service
No full textWe consider a finite capacity single server queue in which the customers arrive according to a Markovian arrival process. The customers are served in batches following a ‘general bulk service rule’. The service times, which depend on the size of the batch, are generally distributed. We obtain, in steady-state, the joint distribution of the random variables of interest at various epochs. Efficient computational procedures in the case of phase type services are presented. An illustrative numerical example to bring out the qualitative nature of the model is presented
Superheated Liquid and Supercritical Denatured Ethanol Extraction of Antioxidants from Crimson Red Grape Stems
Get PDFGrapes are widely known for health benefits due to their antioxidant content. In wine production, grape stems are often discarded, though they has a higher content of antioxidants than the juice. The effectiveness of using an environmentally friendly solvent, ethanol, as a superheated liquid and supercritical fluid to extract antioxidant compounds from grape stems of organically grown Crimson Seedless grapes was evaluated. The Ferric Reducing Ability of Plasma (FRAP) assay and the Total Phenolic Content (TPC), or Folin-Ciocalteu assay, were used to quantify the antioxidant power of grape stem extracts. The extractions were performed at temperatures between 160°C and 300°C at constant density. It was found that the optimal extraction temperature was 204°C, at superheated liquid conditions, with a FRAP value of 0.670 mmol Trolox Equivalent/g of dry grape stem. The FRAP values were higher than other studies that extracted antioxidants from grape stems using single-pass batch extractio
Comparison of the Topologies for a Hybrid Energy-storage System of Electric Vehicles via a Novel Optimization Method
No full textThe combination of batteries and ultracapacitors has become an effective solution to satisfy the requirements of high power density and high energy density for the energy-storage system of electric vehicles. Three aspects of such combination efforts were considered for evaluating the four types of hybrid energy-storage system (HESS) topologies. First, a novel optimization framework was proposed and implemented to optimize the voltage level of a battery pack and an ultracapacitor pack for the four types of HESS topologies. During the optimization process, the dynamic programming (DP) algorithm was iteratively applied to determine the optimal control actions. The simulation results with DP were used to evaluate the energy efficiency of different HESS topologies at different voltage levels. Second, the optimized voltage level of the battery and ultracapacitor in each topology indicates that a higher voltage level usually results in a better system performance. The simulation results also illustrate that the optimized rated voltage level of the battery pack is approximately 499.5 V, while for the ultracapacitor pack, the optimized voltage level is at its maximum allowed value. Note that the constraint of the battery voltage is initialized at 200–600 V. Third, the control rules for different HESS topologies were obtained through the systematic analysis of the simulation results. In addition, advantages and disadvantages of the four topologies were summarized through evaluation of the efficiency and operating currents of the batteries and the ultracapacito
Modeling of Coupled Physio-Chemical Processes of a Liquid Droplet between Two Contacting Porous or Non-porous Materials
No full textA Computational model to solve the coupled transport equations with chemical reaction and phase change for a liquid droplet between two approaching porous or non-porous surfaces, is developed. The model is general therefore it can be applied to toxic chemicals (contact hazard), drug delivery through porous organs and membranes, combustion processes within porous material, and liquid movements in the ground. The equation of motion and the spread of the incompressible liquid available on the primary surface for transfer into the contacting surface while reacting with other chemicals (or water) and/or the solid substrate are solved in a finite difference domain with adaptive meshing. The comparison with experimental data demonstrated the model is robust and accurate. The impact of the initial velocity on the spread topology and mass transfer into the pores is also addressed
Compression Transmission Collar for Fastening
Get PDFA compression transmission collar apparatus (20) for implantation into a bone (22) with a hole (28) having a hole wall (32) comprising an intramedullary nail (34) defining a bore (40) and a threaded fastener (42) and a compression transmission collar (58) including an exterior face (64) and a top edge (60) and a bottom edge (62) and a first end (70) intersecting the top edge (60) at an acute angle and the bottom edge (62) at an obtuse angle and a second end (72) intersecting the top edge (60) at an obtuse angle and the bottom edge (62) at an acute angle and the first end (70) partially overlapping and opposing the second end (72) to define a slit (74) such that applying a compressional load to the top edge (60) causes the first end (70) to slide relative to and along the second end (72) causing the compression transmission collar (58) to compress axially and expand radially pressing the exterior face (64) against the hole wall (32)