Dynamics of coupled vortices in layered magnetic nanodots

The spin dynamics are calculated for a model system consisting of magnetically soft, layered nanomagnets, in which two ferromagnetic (F) cylindrical dots, each with a magnetic vortex ground state, are separated by a non-magnetic spacer (N). This permits a study of the effects of interlayer magnetostatic interactions on the vortex dynamics. The system was explored by applying the equations of motion for the vortex core positions. The restoring force was calculated taking into account the magnetostatic interactions assuming a realistic surface charge free spin distribution. For tri-layer F/N/F dots with opposite chiralities and the same core polarizations (lowest energy state), two eigenmodes are predicted analytically and confirmed via micromagnetic simulations. One mode is in the sub-GHz range for submicron dot diameters and corresponds to quasi-circular rotation of the cores about the dot center. A second mode is in the MHz range corresponding to a small amplitude rotation of the mean core position. The eigenfrequencies depend strongly on the geometrical parameters of the system, suggesting that magnetostatic effects play a dominant role in determining the vortex dynamics.Comment: One PDF file including text and 4 figure

Fresnel zone processing of synthetic aperture radar data

Fresnel zone processing of synthetic aperture rada

Non-linear vortex dynamics and transient effects in ferromagnetic disks

We report a time resolved imaging and micromagnetic simulation study of the relaxation dynamics of a magnetic vortex in the non-linear regime. We use time-resolved photoemission electron microscopy and micromagnetic calculations to examine the emergence of non-linear vortex dynamics in patterned Ni80Fe20 disks in the limit of long field pulses. We show for core shifts beyond ~20-25% of the disk radius, the initial motion is characterized by distortions of the vortex, a transient cross-tie wall state, and instabilities in the core polarization that influence the core trajectories.Comment: 11 pages, 3 figures, submitted to Phys. Rev. Let

Auto-positioning ultrasonic transducer system

An ultrasonic transducer apparatus and process for determining the optimal transducer position for flow measurement along a conduit outer surface. The apparatus includes a transmitting transducer for transmitting an ultrasonic signal, said transducer affixed to a conduit outer surface; a guide rail attached to a receiving transducer for guiding movement of a receiving transducer along the conduit outer surface, wherein the receiving transducer receives an ultrasonic signal from the transmitting transducer and sends a signal to a data acquisition system; and a motor for moving the receiving transducer along the guide rail, wherein the motor is controlled by a controller. The method includes affixing a transmitting transducer to an outer surface of a conduit; moving a receiving transducer on the conduit outer surface, wherein the receiving transducer is moved along a guide rail by a motor; transmitting an ultrasonic signal from the transmitting transducer that is received by the receiving transducer; communicating the signal received by the receiving transducer to a data acquisition and control system; and repeating the moving, transmitting, and communicating along a length of the conduit

The Role of Kentucky State-Supported Postsecondary Education in Creating a Healthier Citizenship

Citizens within the United States of America (USA) and the Commonwealth of Kentucky exhibit indicators of lessened health status in a variety of areas. Many chronic diseases and conditions are due to individual lifestyle behaviors, which can be modified through the implementation of dedicated health and wellness programming. Such programs, often housed within institutions of higher education, have the ability to impact many individuals including students, faculty, staff, and community members. This dissertation is a report of a mixed-methods study that begins to explore how state-supported postsecondary institutions may be able to impact individual behavior and thus, resulting health outcomes. This relationship is not only beneficial for the targeted individuals but also for the institutions, which may experience heightened success and sustainability. This research employs both quantitative and qualitative methods to gain an understanding of the current level of influence of state-supported postsecondary education in Kentucky on the health of its citizenship. Those working in various on-campus health and wellness departments at the University of Kentucky, University of Louisville, and Eastern Kentucky University were surveyed. Next, key leaders at each university involved with these programming efforts were interviewed along with Kentucky Council on Postsecondary Education officials, to gain an understanding of the leadership perspectives surrounding this issue. Finally, site visits at each university were completed to elicit knowledge regarding campus environments and how supportive they are in positively influencing individual health and wellbeing. It is possible that with more extensive findings across the Commonwealth of Kentucky and across the USA, a greater rationale can be made for institutional and state-wide leadership support of health and wellness programming efforts on college campuses. Resulting outcomes have great potential to be both robust and reciprocal to the university and its community members

A Comparative Analysis of School Counselors\u27 and School Principals\u27 Perceptions of School Counselors\u27 Activities

The purpose of this quantitative, cross-sectional survey study was to compare school counselors’ and principals’ perceptions of the frequency with which school counselors perform activities that align with the ASCA National Model (ASCA, 2005) and those activities that do not, as measured by the School Counselor Activity Rating Scale (SCARS) (Scarborough, 2005). Results indicate that the school counselors and principals that participated in the study agreed that school counselors are spending most of their time engaged in activities that align with the ASCA National Model (ASCA, 2005). Significant differences (p \u3c .05) appeared on 10 items in which five were related to counseling activities, primarily as they relate to small group counseling. Principals indicated their school counselors were conducting small group activities related to academic and substance abuse issues more frequently than the school counselors indicated. Other areas that showed significant differences (p \u3c .05) between school counselors’ and principals’ responses included conducting classroom guidance lessons on substance abuse issues, consulting with school staff regarding students’ behavior, and such coordination activities as professional development and school counseling advisory teams. School counselors indicated they engaged in the non-counseling activity of substituting/covering classes more frequently than principals indicated (p = .032). Implications for school counselors, principals, and counselor education and education administration faculty are discussed

ENERGY DRINK CONSUMPTION (WITH AND WITHOUT ALCOHOL) AND ITS RELATIONSHIP TO RISKY BEHAVIOR, RISK AWARENESS, AND BEHAVIORAL INTENTION IN COLLEGE STUDENTS

The purpose of this study was to assess the relationships between energy drink consumption (with and without alcohol) and other risky behaviors; students’ overall awareness level of the risks for consuming energy drinks; and overall behavioral intention to consume energy drinks among college students at the University of Kentucky. A total of 277 students enrolled during the Spring 2012 semester responded to the online survey, 46.5% (n=129) of which were considered energy drink users. Students classified as energy drink users participated in other risky behaviors more often than non-users (p=0.001). In addition, energy drink users exhibited a higher awareness level for the risks associated with energy drink consumption both with (p=0.000) and without (p=0.000) alcohol. Those who were more aware of the risks associated with energy drink consumption, both with (p=0.001) and without (p=0.001) alcohol, were found to have increased intention to consume energy drinks within the next month compared to those with lower awareness levels. There is a need for future research on this topic, as well as a need for expanded education and intervention programming for college students regarding the risks of energy drink consumption (with and without alcohol)

Motivational Interviewing to Enhance Weight Loss and Eating Self-Efficacy in Overweight and Obese Adults

Greater than six in ten adults in the United States are overweight or obese which can lead to cardiovascular disease, Type II Diabetes, joint injury and some forms of cancer, costing billions of healthcare dollars each year. Weight loss is difficult, as is maintaining weight loss. The purpose of this project is to investigate if use of the evidenced based (EB) intervention, motivational interviewing (MI), will enhance weight loss and eating self-efficacy (ESE) in overweight and obese adults seeking weight loss at a weight loss clinic over the course of eight weeks. Participants who received MI in addition to current weight loss strategies lost significantly more weight (-2.74 kg, p \u3c .05) between the four and eight week visits as compared patients who did not receive MI (-1.3222 kg). The overall weight change over the course of this eight week study in patients who received MI was -6.7733 kg as compared to patients who did not receive MI which was -4.5717 kg. ESE was significantly improved from the initial visit of 4.8733 (p \u3c .05) to the four week visit of 4.6733 (p \u3c .05) and 4.3267 (p \u3c .05) at eight weeks in participants who received monthly MI sessions. Keywords: Weight Loss, Motivational Interviewing, Obesity, Self-efficac