Comparative Fatigue Analysis of Metals and Polymers for Engineering Applications

Rapid prototype polymers are becoming increasingly popular for engineering applications, particularly during the design phase as a quick check for size and fit; however they are not currently widely-used for load-bearing applications. Current research at the University of Arkansas Department of Mechanical Engineering focused on rapid prototyped polymers by doing cyclical tensile testing. The results were analyzed for strain energy and fatigue data. When cycling at lower percentages of ultimate stress, unusual strain energy patterns were observed. This research details testing of metals in order to compare strain energy patterns to those of the rapid prototype polymers

Resurgence in Dogs

After a long tradition of using aversive training techniques, animal trainers have now widely adopted science-based methods using positive reinforcement. The field of applied behavior analysis routinely employs procedures to preempt problem behaviors by establishing and maintaining more acceptable alternative behaviors. Previous studies have shown that some of these procedures can nevertheless result in recurrence of original problematic behavior once training is completed and reinforcement of the alternative behavior is discontinued, a phenomenon called “resurgence.” Although observed in many species (e.g., rats, fish, and humans), resurgence has not been demonstrated with dogs, one of the most commonly trained animals in the world. Five experimentally naïve dogs served in the present study. Four were first trained to perform an arbitrary target behavior, which subsequently was extinguished completely, and then, an alternative target behavior was reinforced in its place. When reinforcement for both behaviors then was discontinued, none of these dogs showed resurgence as expected from the literature. A fifth dog with an existing minor problem behavior (begging) was taught a more acceptable alternative behavior (lying in a dog bed across the room). When that new behavior was subjected to extinction, the previous problem behavior recurred as expected. Finally, when the recurring begging was also subjected to extinction, lying in bed then returned and was successfully recaptured (maintained) through reinforcement. The results of these experiments suggest that resurgence does occur in dogs, but the specific contingencies of reinforcement employed to establish the competing repertoires are critical to producing the phenomenon

Facilitators And Barriers To Compliance Of Middle-Aged Hypertensive African-American Adults

Hypertension is a major risk factor for cardiovascular disease, such as atherosclerosis, heart attack, and stroke. Surveys indicate that one out of four Americans has high blood pressure. It occurs more often in men than women and is most common in African-American males. Despite the fact that there are constantly improving treatments available, many hypertensive patients are noncompliant with prescribed treatment plans. The focus of this descriptive study was to identify facilitators and barriers to compliance in hypertensive middle-aged African American adults. Pender\u27s Health Promotion Model served as the theoretical framework. The research question guiding this study was as follows: What are the facilitators and barriers in regard to compliance in hypertensive middle- aged African-American adults? Utilizing convenience sampling, a questionnaire was presented to 50 middle-aged African-American adults who reside in the Delta area of a southeastern state. Data collected from the questionnaire were analyzed using descriptive statistics, such as means, frequency, and percentages. Analysis of the data found 1 1 1 that 26% of the sample reported daily medication compliance. Thirty-one percent verified low-salt dietary modifications. Regular exercise was also confirmed by 56% of the participants. Subjects reported that the top two facilitators to hypertensive treatment compliance were adequate transportation to pick up medications and income or insurance to pay for medications, respectively. The two major barriers to hypertensive treatment compliance were forgetting medication or not liking to take medication daily and not liking to exercise. The findings of this study indicated that respondents identified physical or external factors as the greatest facilitators to hypertensive treatment compliance. They also suggested that the primary barriers are internal or personal perceptions. Recommendations for further study include replication of this study with a larger sample size and more studies with a valid and reliable research tool as well as incorporation of teaching and learning strategies that effect compliance to medication treatment

An investigation of how vocal exercises affect the range, respiration, and pitch accuracy of junior high students.

The technique of warming up the voice should be a major part of any systematic vocal pedagogy. Every singer needs to have an established warm-up procedure”. (Miller 22) Often, the only place a young singer can receive frequent [vocal] instruction is in the school choral rehearsal, and without regular, supervised practice and guidance, the adolescent singer has little chance of developing a quality instrument . (Wilson 42) Good vocal pedagogy is essential . (Allen 29) A persistent problem in music education is that many never learn to use their singing voices confidently , states Dr. Kenneth Phillips. ( Training the Child Voice 19) The purpose of this investigation was to study the effects of vocal exercises on the range, respiration, and pitch accuracy of seventh-grade students. These exercises were practiced for the first ten minutes of every forty minute class, five times a week, for a period of fourteen weeks. The experimental design provided for pretesting posttesting with an experimental and control group. A stratified random sample was drawn from seventh-grade chorus members of Kim Junior High School in Council Bluffs, Iowa. Each group contained 35 students. Students were pretested individually for their range, respiration, and pitch accuracy. Training consisted of a fourteen­ week experimental treatment with testing at the beginning and again at the end of the fourteen weeks. The researcher conducted the exercises for the experimental group for ten minutes of each forty minute rehearsal. The control group did not rehearse vocal exercises. A test was given to both groups at the end of the fourteen weeks for vocal range to record changes. There was also a test given in respiration for breath control, as measured by a stopwatch for the amount of time a student can sustain an s sound, (Appendix B, page 2 #6) and breath capacity as measured by a multi-spirometer for the peak expiratory flow rate (PEF) and forced vital capacity (FVC). The third test was for pitch accuracy. Students were asked to sing America (Appendix D, page 2) and were judged for the accuracy of the forty-one pitches. A ordinal scale of one through five was used, with “five being the ability to match all pitches accurately, and one as less than ten accurate pitches. This study was designed to answer the following research question: Will vocal exercises, practiced 50 minutes a week for fourteen weeks, have an effect on the range, respiration, and pitch accuracy of seventh grade students? To determine the. effect of vocal exercises on the increased range, respiration, and pitch accuracy of seventh-grade students, the following null and alternative hypotheses were tested: 1. There will be no significant difference in the range of the control group and experimental group after fourteen weeks of vocal exercises. 1a. There will be a significant difference in the increased range of the experimental group as opposed to the control group. 2. There will be no significant difference in ·the breath capacity of the experimental and control group after fourteen weeks of vocal exercises. 2a. There will be a significant difference in the increased breath capacity of the -experimental group as opposed to the control group. 3. There will be no significant difference in the breath control of the experimental and control group after fourteen weeks of vocal exercises. 3a. There will be a significant difference in the increased breath control of the experimental group as opposed to the control group. 4. There will be no significant difference in the pitch accuracy of the experimental and control group after fourteen weeks of vocal exercises. 4a. There will be a significant difference in the pitch accuracy of the experimental group as opposed to the control group. As a result of this study the following conclusions were drawn: In the area of pitch accuracy there was not a significant difference between the experimental and control groups as a result of fourteen weeks of vocal exercises. There was a significant difference in the increased range, breath capacity and breath control of the experimental as opposed to the control group as a result of fourteen weeks of exercises. These conclusions support the need for progressive, well-established vocal exercises to be used consistently at the seventh-grade level

A Study of Decision Analysis Methods in Aerospace Technology Assessments

Managers of aerospace technology programs and projects are faced with the challenge of making technology portfolio decisions under conditions of limited data, rapidly changing macro level factors and organizational uncertainties. To help make these technology investment decisions, some aerospace managers and analysts have used techniques from the field of decision analysis. In addition, there have been a limited number of research studies of real decision problems. This dissertation presents the results of a non-experimental examination of the use of decision analysis methods for the assessment of aerospace technology portfolios. A web-based survey instrument was developed based on the results of a pilot study conducted using cognitive interviewing techniques. Quantitative data was collected from government and industry aerospace researchers and managers with experience in research and/or with the development of aerospace technology portfolios and the completion of their assessments. Structural equation modeling techniques were used to test the study hypotheses. Conclusions were drawn and recommendations were made for future research

Homogeneously bright, flexible and foldable lighting devices with functionalised graphene electrodes

Alternating current electroluminescent technology allows the fabrication of large area, flat and flexible lights. Presently the maximum size of a continuous panel is limited by the high resistivity of available transparent electrode materials causing a visible gradient of brightness. Here, we demonstrate that the use of the best known transparent conductor FeCl$_{3}$-intercalated few-layer graphene boosts the brightness of electroluminescent devices by 49$\%$ compared to pristine graphene. Intensity gradients observed for high aspect ratio devices are undetectable when using these highly conductive electrodes. Flat lights on polymer substrates are found to be resilient to repeated and flexural strains.Comment: Published on ACS Materials and Interface

Assessing Mondragon: Stability & Managed Change in the Face of Globalization

By drawing on new interview evidence gathered during several field trips and new financial and economic data from both external and internal sources, we document and assess the changing economic importance and performance of the Mondragon group of cooperatives as well as the two largest sectors within the group. Compared to conventional firms in the Basque Country and Spain, and producer co-ops (PCs) and employee owned firms elsewhere, in general we find evidence of growing group importance and strong performance and a similarly strong record for the industrial and retail divisions...employee ownership, producer cooperatives, labor managed firm, productive efficiency, Mondragon

Granulomatous fasciitis followed by morphea profunda: Is granulomatous fasciitis part of a spectrum of deep morphea? A case report and review of the literature.

Although eosinophilic fasciitis is known to be part of the deep morphea spectrum, this first report of the coexistence of granulomatous fasciitis and morphea profunda suggests that granulomatous fasciitis may also be a part of the spectrum of deep morphea

A bijection on core partitions and a parabolic quotient of the affine symmetric group

Let $\ell,k$ be fixed positive integers. In an earlier work, the first and third authors established a bijection between $\ell$-cores with first part equal to $k$ and $(\ell-1)$-cores with first part less than or equal to $k$. This paper gives several new interpretations of that bijection. The $\ell$-cores index minimal length coset representatives for $\widetilde{S_{\ell}} / S_{\ell}$ where $\widetilde{S_{\ell}}$ denotes the affine symmetric group and $S_{\ell}$ denotes the finite symmetric group. In this setting, the bijection has a beautiful geometric interpretation in terms of the root lattice of type $A_{\ell-1}$. We also show that the bijection has a natural description in terms of another correspondence due to Lapointe and Morse.Comment: 23 page

Quantifying Syringe Exchange Program Operational Space in the District of Columbia.

Syringe exchange programs (SEPs) are effective structural interventions for HIV prevention among persons who inject drugs. In 2000, a buffer zone policy (the 1000 Foot Rule) was implemented in Washington, DC, that prohibited SEP operations within 1000 feet of schools. We examined changes in the amount of legal SEP operational space over time. We used data pertaining to school operations and their approximate physical property boundaries to quantify the impact of the 1000 Foot Rule on legal SEP operational space from its implementation in 2000-2013. Adherence to the 1000 Foot Rule reduced SEP operational space by more than 50 % annually since its implementation. These findings demonstrate the significant restrictions on the amount of legal SEP operational space in Washington, DC, that are imposed by the 1000 Foot Rule. Changing this policy could have a significant impact on SEP service delivery among injectors