<p>The demand of small size electronic systems has been increasing for several decades. The physical size of systems is reduced due to advancements in integrated circuits. With reduction in size of electronic systems, there is also an increasing demand of small and low cost antennas. Patch antennas are one of the most attractive antennas for integrated RF front end systems due to their compatibility with microwave integrated circuits. To fulfil the demand of integrated RF front end systems, a design of microstrip patch antenna with optimum performance at 70GHz is investigated. The procedure could be extended to design other planar antennas that act in a similar way.</p><p>In this work, three different design methods to design patch antennas for applications at 70GHz are investigated that include use of analytical models, numerical optimization, and numerical variation of dimensions. Analytical models provide a basic understanding of the operation of a patch antenna and they also provide approximate dimensions of a patch antenna for a targeted frequency without using numerical simulations. However, as the operating frequencies of RF systems reach mm-wave frequencies, we expect that the accuracy of analytical models become less accurate. For example, the excitation of substrate modes and effect of ground size are not predicted in simple analytical models.</p><p>Due to these expected limitations of the analytical design methods, the accuracy of these models is investigated by numerical electromagnetic field simulations. In this work, CST Microwave Studio Transient Solver is used for that purpose. In order to make sure that the appropriate settings of the solver are applied, the simulation settings such as mesh density, boundary conditions and the port dimensions are investigated. The simulation settings may affect computation time and convergence of the results. Here, in this work, the accuracy of the simulator for a specific design of inset feed rectangular patch antenna is verified. The patch dimensions obtained from analytical calculations are optimized at 70GHz by using the optimizer of the transient solver. The patch dimensions obtained from optimizer are verified by varying the patch dimensions in equidistant steps around the found result of the optimizer.</p><p>In a rectangular microstrip patch antenna design, the use of a width of 1.5 times the length is an approximate rule of thumb [1] for low dielectric constant substrates. It is also investigated how the performance properties of a microstrip patch antenna are affected by varying the width to length ratio of the patch. There are occasions where a different ratio is required because of space limitations, or to change the input impedance. The patch designs having various width to length ratios were optimized with the feed location.</p><p>The analytically calculated dimensions provided good initial values of the rectangular patch antenna for further optimization using more accurate techniques. The design have been optimized at 70GHz for the investigated mesh density, boundary conditions and the port dimensions. The numerical variation of dimensions is found to be most reliable among the investigated design methods but it is more complicated with many parameters.</p>

The demand of small size electronic systems has been increasing for several decades. The physical size of systems is reduced due to advancements in integrated circuits. With reduction in size of electronic systems, there is also an increasing demand of small and low cost antennas. Patch antennas are one of the most attractive antennas for integrated RF front end systems due to their compatibility with microwave integrated circuits. To fulfil the demand of integrated RF front end systems, a design of microstrip patch antenna with optimum performance at 70GHz is investigated. The procedure could be extended to design other planar antennas that act in a similar way. In this work, three different design methods to design patch antennas for applications at 70GHz are investigated that include use of analytical models, numerical optimization, and numerical variation of dimensions. Analytical models provide a basic understanding of the operation of a patch antenna and they also provide approximate dimensions of a patch antenna for a targeted frequency without using numerical simulations. However, as the operating frequencies of RF systems reach mm-wave frequencies, we expect that the accuracy of analytical models become less accurate. For example, the excitation of substrate modes and effect of ground size are not predicted in simple analytical models. Due to these expected limitations of the analytical design methods, the accuracy of these models is investigated by numerical electromagnetic field simulations. In this work, CST Microwave Studio Transient Solver is used for that purpose. In order to make sure that the appropriate settings of the solver are applied, the simulation settings such as mesh density, boundary conditions and the port dimensions are investigated. The simulation settings may affect computation time and convergence of the results. Here, in this work, the accuracy of the simulator for a specific design of inset feed rectangular patch antenna is verified. The patch dimensions obtained from analytical calculations are optimized at 70GHz by using the optimizer of the transient solver. The patch dimensions obtained from optimizer are verified by varying the patch dimensions in equidistant steps around the found result of the optimizer. In a rectangular microstrip patch antenna design, the use of a width of 1.5 times the length is an approximate rule of thumb [1] for low dielectric constant substrates. It is also investigated how the performance properties of a microstrip patch antenna are affected by varying the width to length ratio of the patch. There are occasions where a different ratio is required because of space limitations, or to change the input impedance. The patch designs having various width to length ratios were optimized with the feed location. The analytically calculated dimensions provided good initial values of the rectangular patch antenna for further optimization using more accurate techniques. The design have been optimized at 70GHz for the investigated mesh density, boundary conditions and the port dimensions. The numerical variation of dimensions is found to be most reliable among the investigated design methods but it is more complicated with many parameters.

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Cardiovascular diseases are the leading causes of death globally. One contributing factor that can lead to heart failure is a myocardial infarction. When an infarct occurs, an occlusion in the tissue vasculature prevents blood flow beyond this site. It results in scar tissue formation. The scar is non-contractile and reduces the working efficiency of the heart. To compensate, left ventricular remodeling will ensue resulting in enlarging of the left ventricle. This progression of events ultimately culminates in heart failure. One approach to assist patients who have suffered a heart attack is to implant a cardiac patch. Current patches are acellular and aim to retain the geometry of the left ventricle, limiting any ventricular remodeling from occurring. While these patches provide a passive support, it is hypothesized that incorporation of cells into the patches could result in functional support that could help to restore baseline function. To be effective, a cell-populated cardiac patch would need to integrate with the host tissue functionally and mechanically. In this thesis, we developed a fibrin microthread-based composite scaffold with material properties comparable to left ventricular myocardium that promotes regional cardiomyocyte alignment and physiologically relevant contractile strains. We hypothesized that a composite material could be developed where constituents of the material would complement one another to yield a mechanically reinforced scaffold that promotes cardiomyocyte function. Through manipulation of the volume fraction of the components, we manipulated the modulus of the layer without compromising contractile strain or contractile frequency of incorporated cells. Additionally, through strategic restraint of the scaffolds, we utilized cell-mediated compaction to induce a tension pattern that increased alignment of incorporated cells. This corresponded to an increase in contractile strain magnitudes, and an anisotropic contractile wave propagation through the engineered tissue. Finally, we laminated composite layers into a patch mimicking the architecture of ventricular myocardium and found that material properties of the patch were similar to properties of the target tissue. In summary, we designed a biomimetic composite patch with material properties similar to ventricular myocardium that supports cardiomyocyte alignment and contractility to promote functional and mechanical integration upon implantation.

Doctor of Science in Engineering - Engineering / This paper describes the formulation of a design procedure for the rectangular, probe-fed and rectangular, electromagnetically coupled patch antennas. The design procedure is presented in the form of design curves. The design curve data was generated by solving a bandwidth optimization problem subject to a specified minimum gain constraint. Given a particular performance requirement, an appropriate antenna geometry can be found using the design curves. An unavoidable tradeoff between the gain and impedance bandwidth performance parameters is evident from the design curves. The bandwidth and minimum gain configurations for design of the probe-fed patch range from 6.2% and 9.9dBi to 13.2% and 6.1dBi respectively. The bandwidth and minimum gain configurations for design of the electromagentically coupled patch range from 9.5% and 9.7dBi to 44% and 6.0dBi respectively.

Abstract In the present study, the effects of rutaecarpine on ionic currents of NG108-15 neuronal cells were studied. Rutaecarpine (2-100 £gM) suppressed the amplitude of voltage-dependent K+ outward current (IK(DR)) in a concentration-dependent manner. The IC50 value for rutaecarpine-induced inhibition of IK was 11£gM. However, rutaecarpine (20 £gM) had little effect on L-type Ca2+ current. IK(DR) present in these cells is sensitive to the inhibition by quinidine and dendrotoxin, yet not by E-4031. Rutaecarpine enhanced the rate and extent of IK(DR) inactivation, although it had no effect on the initial activation phase of IK(DR). Recovery from block by rutaecarpine (5 £gM) was fitted by a single exponential with a value of 2.87 s. Cell-attached single-channel recordings revealed that rutaecarpine decreased channel activity over the length of the test potential without altering single-channel amplitude. With the aid of binding scheme, a quantitative description of the actions of rutaecarpine on IK(DR) was provided. Under current-clamp configuration, rutaecarpine also prolonged action potential duration in NG108-15 cells without altering other variables of the action potential. The results clearly show that rutaecarpine is a blocker of the KDR channel. The increase in action potential duration induced by rutaecarpine can be explained mainly by its blocking effects on IK(DR).

Successful synaptic transmission at the neuromuscular junction depends on the precise alignment of the nerve terminals with the postsynaptic specialization of the muscle fiber. It is increasingly apparent that this precision is achieved during development and maintained in the adult through signals exchanged between motoneurons and their target muscle fibers that serve to coordinate their spatial and temporal differentiation. There is increasing evidence that retinoic acid (RA), a derivative of Vitamin A, plays important roles in the development of nervous system. Here we specifically test this notion by examining the effect of RA on synaptic activity at developing neuromuscular synapse in Xenopus cell culture using whole-cell patch clamp recording. Bath application of RA rapidly (with a 10~15 min latency) and specifically enhances the spontaneous ACh secretion and the action of ¡@RA is reversible. The synaptic potentiation induced by RA was not occluded in the presence of protein synthesis inhibitor, Anisomycin and Cycloheximide,¡@suggesting this is transcription-independent. Selective RAR

Activation of a5??1 integrin potentiates L-type calcium current in vascular smooth muscle, which is partly mediated by tyrosine phoshorylation of the a1c channel subunit. Expressed rabbit VSM and neuronal isoforms are also potentiated by a5??1 integrin activation and require dual phosphorylation of a1c by PKA and c-Src. To explore common mechanisms of regulation by a5??1 integrin, whole cell patch clamp experiments were used to investigate the effects of a5??1 integrin antibody on expressed cardiac calcium channels. In HEK cells transfected with a1c, ??2a and a2-d1 subunits alone, currents increased 1.8 ?? 2.0 fold on application of a5??1 antibody. The potentiation was almost completely abolished on the application of PKI, a highly specific Protein Kinase A (PKA) inhibitor. The expressed currents increased 2.0 ?? 2.2 fold on application of PKA activator 8-Br-cAMP, and abolished by PKI. Our results suggest that regulation of L-type calcium channels by a5??1 integrin is a general mechanism shared by VSM, neuronal and cardiac channels. However, in the cardiac isoform, only PKA phosphorylation is involved.

Conventional routes of drug administration have several disadvantages. The rate and extent of absorption can vary greatly depending on the drug, its formulation, the presence or absence of food, drug interactions, and the pH of gastrointestinal fluids. Extensive first-pass metabolism can greatly reduce the absorption of many drugs. Better dosage forms or drug delivery mechanisms could minimize some of these problems. The pharmaceutical industry has recognized the need for, and has developed many new, novel drug delivery systems. Drugs that previously experienced diminished effective concentrations due to the first-pass effect may now be given by a novel route. The dosing frequency of many drugs may be reduced when administered by a novel route or site. Transmucosal drug delivery (TMDD) via the buccal mucosa is one site that is suited to rapid drug absorption and systemic delivery. Drugs selected for TMDD must have physiochemical properties that will allow them to penetrate the mucosa and produce therapeutic blood concentrations. This study utilized a buccal patch less than 1.5 cm in length to deliver albuterol and butorphanol-two drugs with dissimilar physiochemical properties. The purpose of this study was to establish pharmacokinetic parameters and the bioavailability of albuterol and butorphanol when administered intravenously and buccally. Three dogs weighing at least 20 kg were studied using a randomized crossover design, each receiving albuterol and butorphanol by buccal and intravenous administration. Blood samples were collected and analyzed using ELISA. Values for pharmacokinetic parameters were analyzed using compartmental and non-compartmental models. For albuterol, extrapolated Cmax and Co after buccal and IV administration were 10.28 ± 2.77 and 57.74 ± 9.04 ng/ml, respectively. Volume of distribution at steady state (Vss) was 2.13 ± 1.30 L/kg and Cl was 4.73 ± 3.91 ml/min/kg. A significant difference existed between the disappearance rate constant of buccal and intravenous albuterol administration. The disappearance half-lives of buccal and IV albuterol were 160.96 ± 24.19 and 364.20 ± 115.20 min, respectively. The bioavailability of buccally administered albuterol was 35%. Maximal concentration (Cmax) and Co after buccal and IV butorphanol administration were 6.66 ± 1.65 and 8.24 ± 5.55 ng/ml, respectively. Volume of distribution at steady state (Vss) was 27.58 ± 10.14 L/kg and Cl was 137.87 ± 19.55 ml/min/kg. The half-life of buccally administered butorphanol was 259.15 ± 33.12 min and the half-life of IV butorphanol was 172.12 ± 94.95 min. The bioavailability of buccally administered butorphanol was 606%. The buccal patch used in this study achieved systemic concentrations for both albuterol and butorphanol. Further studies are needed to determine if therapeutic drug concentrations can be achieved with the buccal patch and if the patch can result in clinical efficacy.

Doctor of Philosophy / Department of Horticulture and Natural Resources / Jack Fry / Megan Kennelly / Zoysiagrasses (Zoysia spp.) use C4 metabolism and are more drought resistant than C3 grasses. However, the long dormancy period between autumn and spring limits the use of zoysiagrass by homeowners and professional turfgrass managers. In addition, large patch has become the primary pest on zoysiagrass, and improved cultivars with good cold hardiness and large patch resistance are needed in the transition zone. Tall fescue (Schedonorus arundinaceus Schreb), a C3 grass, is used frequently in Kansas due to its heat and drought tolerance compared to some other C3 grasses. However, brown patch (Rhizoctonia solani) is the main disease limiting its growth in summer. Alternatively, mixing zoysiagrass with tall fescue may help reduce brown patch incidence. The objective of these projects were to: (1) evaluate methods for establishing a perennial mixture of seeded zoysiagrass and tall fescue; (2) determine whether a zoysiagrass/ tall fescue polystand is less susceptible to brown patch and results in improved summer quality compared to a tall fescue monostand; and (3) evaluate experimental zoysiagrass genotypes to identify one or more potential new cultivars which have high quality and tolerance to cold and large patch. I found that polystands of zoysiagrass and tall fescue were most successfully established by seeding zoysiagrass at 49 kg ha-1 in June and tall fescue at 392 kg ha-1 in September into the established zoysiagrass sward. Polystand establishment was also superior at a 1.9 cm mowing height than a 5.1 cm mowing height. The resulting mixture resulted in improved turf color in late fall and early spring compared to a zoysiagrass monostand. In addition, using a zoysiagrass-tall fescue polystand reduced brown patch by up to 21% compared to a tall fescue monostand. In the zoysiagrass breeding project, I identified ten progeny out of sixty evaluated that had better tolerance to large patch (up to 40 % less plot area affected) and better quality compared to Meyer zoysiagrass, which is the standard cultivar used in the transition zone.