Computation of Spiral Spectra

A computational linear stability analysis of spiral waves in a reaction-diffusion equation is performed on large disks. As the disk radius R increases, eigenvalue spectra converge to the absolute spectrum predicted by Sandstede and Scheel. The convergence rate is consistent with 1/R, except possibly near the edge of the spectrum. Eigenfunctions computed on large disks are compared with predicted exponential forms. Away from the edge of the absolute spectrum the agreement is excellent, while near the edge computed eigenfunctions deviate from predictions, probably due to finite-size effects. In addition to eigenvalues associated with the absolute spectrum, computations reveal point eigenvalues. The point eigenvalues and associated eigenfunctions responsible for both core and far-field breakup of spiral waves are shown.Comment: 20 pages, 13 figures, submitted to SIAD

Mentoring and Student Perspectives in Online Graduate Education

Effective social change relies upon successfully educating professionals. This qualitative study will integrate rapid expansion of online learning with best practices in graduate education. An innovative pilot mentoring program for graduate students will be assessed. The study addresses a gap in the literature on student perceptions of the mentoring process.https://scholarworks.waldenu.edu/archivedposters/1026/thumbnail.jp

Personal Counseling in Academic Programs with Counselor Trainees

Counseling programs are responsible for harm caused by their counselor trainees. This study examined the effect of participating in personal counseling on basic clinical skills using the Counseling Self-Estimate Inventory. This article discusses this study’s inconclusive results and implications for the development of counselors and counseling programs

Personal Counseling in Academic Programs with Counselor Trainees

Counseling programs are responsible for harm caused by their counselor trainees. This study examined the effect of participating in personal counseling on basic clinical skills using the Counseling Self-Estimate Inventory. This article discusses this study’s inconclusive results and implications for the development of counselors and counseling programs

The Sexual History Polygraph Examination and Its Influences on Recidivism

The polygraph in postconviction sex offender testing is used to assist in the treatment and supervision of convicted sex offenders by more than 70% of the jurisdictions that supervise these offenders in the United States. Prior researchers have failed to convincingly demonstrate how the polygraph can be used to target risk behaviors and reduce recidivism. Consequently, the use of the sexual history polygraph examination (SHPE) has not been demonstrated to reduce recidivism. We sought answers as to how the SHPE influences the behaviors of sexual offenders required to undergo a SHPE, and whether or not there is a difference in recidivism between those offenders who undergo a SHPE as compared to those who do not. Within the group that took a polygraph, recidivists went longer before taking a SHPE, and there was a significant difference in recidivism between those who took a polygraph and those who did not. This information may be useful in assisting other jurisdictions both in the United States and internationally in making better choices in the implementation of supervision and getting the maximum return in the use of the polygraph. It is hoped that ultimately this would lead to more knowledgeable decisions to promote positive social change for the sex offender, which would ultimately lead to positive social change in the community by reducing recidivism of childhood sexual abuse among convicted sex offenders

Inside the Exine and Perine: Understanding the Production and Evolution of Sporopollenin in Seed-Free Land Plants

The recalcitrant polymer sporopollenin is the primary component that contributes to the durable nature of spore and pollen walls. There has been serious interest in this enigmatic material and recent probing has unlocked the structure of this polymer. Prior to this discovery researchers utilized knockout mutants to parse out the structure of sporopollenin contributing to a biosynthetic pathway. The anther-specific chalcone synthase-like (ASCL) protein has been implicated in a key step in this pathway. Previously ASCL Knockout mutants of Physcomitrium patens have been utilized to understand the evolution of this gene. This project aims to build on these foundational studies and focus on using transmission electron microscopy (TEM) and scanning electron microscopy (SEM) techniques to ascertain a precise beginning of disruption to spore development. Along with TEM we utilize the recent surge in genomic sequencing to construct phylogenetic trees built with amino acid sequence comparison. Amino acid sequences were combined with anatomical data of various land plant taxa to construct a matrix model to correlate evolution of the ASCL protein with spore and pollen anatomy. Our findings indicate early signs of disruption prior to Spore mother cell division not previously observed. We also contribute to the growing understanding of ASCL evolution by finding novel ASCL homologs

An Innovative Approach to Action Research in Family Violence Prevention

Violence prevention remains a priority in the current public health agenda because of continuing high rates and debilitating effects of violence that exist across the globe (U.S. Department of Health and Human Services, Administration on Children, Youth and Families [USDHHS-ACF], 2009; World Health Organization [WHO], 2013). This article presents the use of an innovative qualitative study developed from community action research methods in the area of family violence. By applying the combined framework of force field analysis (Lewin, 1958) and the public health model (Centers for Disease Control, 2002; Knox & Aspy, 2011), the current study identified factors that positively and negatively influenced the ability of family violence prevention practitioners to apply research to their practice. Results from the current study led to the development of an action plan to increase the application of research to practice in the area of family violence prevention programming

Nanoparticle growth following photochemical α‐ and β‐pinene oxidation at Appledore Island during International Consortium for Research on Transport and Transformation/Chemistry of Halogens at the Isles of Shoals 2004

Nanoparticle events were observed 48 times in particle size distributions at Appledore Island during the International Consortium for Atmospheric Research on Transport and Transformation/Chemistry of Halogens on the Isles of Shoals (ICARTT/CHAiOS) field campaign from 2 July to 12 August of 2004. Eighteen of the nanoparticle events showed particle growth and occurred during mornings when peaks in mixing ratios of α‐ and β‐pinene and ozone made production of condensable products from photochemical oxidation probable. Many pollutants and other potential precursors for aerosol formation were also at elevated mixing ratios during these events, including NO, HNO3, NH3, HCl, propane, and several other volatile organic carbon compounds. There were no consistent changes in particle composition, although both submicron and supermicron particles included high maximum concentrations of methane sulfonate, sulfate, iodide, nitrate, and ammonium during these events. Nanoparticle growth continued over several hours with a nearly linear rate of increase of diameter with time. The observed nanoparticle growth rates varied from 3 to 13 nm h−1. Apparent nanoparticle aerosol mass fractions (yields) were estimated to range from less than 0.0005 to almost 1 using α‐ and β‐pinene as the presumed particle source. These apparent high aerosol mass fractions (yields) at low changes in aerosol mass are up to two orders of magnitude greater than predictions from extrapolated laboratory parameterizations and may provide a more accurate assessment of secondary organic aerosol formation for estimating the growth of nanoparticles in global models

2017 Walden University Research Symposium

Welcome to the 2017 Walden University Research Symposium. We are glad you can join us in celebrating our 10th anniversary of this Walden University tradition. The Research Symposium is an annual event that showcases research projects from our academic community, especially work by our recent graduates. If there is a theme this year, beyond their shared focus on social change, it would be research aimed at “assuring success” for a variety of people and groups. The presentations at a symposium appear in two different formats • Poster presentations provide an opportunity for researchers to engage with all individuals attending the symposium and potentially to network with other interested researchers. New to this year’s symposium are poster presentations by local alumni who have continued the research they started as doctoral students. • Using a roundtable presentation format, a select group of researchers is available for interactive discussions of their work, with handouts and visual materials available to support the discussion. For this symposium, we are highlighting the in-progress research by fellows associated with Walden University’s Center for Social Change. The “magic” of a research symposium can be found in the interactions between presenters and audience, however. So, please, don’t be shy—step up, ask questions, make comments, and enjoy the experience.https://scholarworks.waldenu.edu/current/1000/thumbnail.jp

Pathological Features of Breast Cancer seen in Northwestern Tanzania: A Nine Years Retrospective Study.

Breast cancer is more common in Western Countries compared to African populations. However in African population, it appears that the disease tends to be more aggressive and occurring at a relatively young age at the time of presentation. The aim of this study was to describe the trend of Breast Cancer in Northwestern Tanzania. This was a retrospective study which involved all cases of breast cancer diagnosed histologically at Bugando Medical Center from 2002 to 2010. Histological results and slides were retrieved from the records in the Pathology department, clinical information and demographic data for patients were retrieved from surgical wards and department of medical records. Histology slides were re-evaluated for the histological type, grade (By modified Bloom-Richardson score), and presence of necrosis and skin involvement. Data was entered and analyzed by SPSS computer software version 15. There were 328 patients histologically confirmed to have breast cancer, the mean age at diagnosis was 48.7 years (+/- 13.1). About half of the patients (52.4%) were below 46 years of age, and this group of patients had significantly higher tendency for lymph node metastasis (p = 0.012). The tumor size ranged from 1 cm to 18 cm in diameter with average (mean) of 5.5 cm (+/- 2.5), and median size of 6 cm. Size of the tumor (above 6 cm in diameter) and presence of necrosis within the tumor was significantly associated with high rate of lymph node metastasis (p = 0.000). Of all patients, 64% were at clinical stage III (specifically IIIB) and 70.4% had lymph node metastasis at the time of diagnosis. Only 4.3% of the patients were in clinical stage I at the time of diagnosis. Majority of the patients had invasive ductal carcinoma (91.5%) followed by mucinous carcinoma (5.2%), Invasive lobular carcinoma (3%) and in situ ductal carcinoma (0.3%). In all patients, 185 (56.4%) had tumor with histological grade 3. Breast cancer in this region show a trend towards relative young age at diagnosis with advanced stage at diagnosis and high rate of lymph node metastasis. Poor Referral system, lack of screening programs and natural aggressive biological behavior of tumor may contribute to advanced disease at the time of diagnosis