Butler Community College

Silicon Carbide (SiC) MOSFET devices are emerging to address Medium Voltage (MV) Utility Applications, where voltages range from 5kV to 15kV [1]. SiC MOSFETS used in these applications can be exposed to peak stress voltages ranging from 5kV to 30kV and drive signals with edges switching at 10kV/μs. Using these devices requires an isolation barrier between the MOSFETS and control circuitry. This paper presents embedded magnetic transformers that address the isolation requirements. Both control and power transformers are designed to exhibit low inter-winding capacitance, while maintaining the clearance and creepage distance that meet IEC standards. In this digest, the transformer device characteristics are presented. The results of AC isolation testing are presented to validate the integrity of the insulating material. The proposed gate drive transformers are aimed at providing a reliable and cost efficient means for implementing power systems using MV SiC MOSFETs

An effectiveness trial found that telemedicine collaborative care for posttraumatic stress disorder (PTSD) significantly increased engagement in trauma-focused psychotherapy (TFP) and improved PTSD symptoms. However, in a subsequent implementation trial, very few veterans enrolled in collaborative care initiated TFP. We conducted a mixed-methods evaluation to determine why veterans did not initiate TFP in the implementation trial. After conducting chart reviews of 1,071 veterans with PTSD enrolled in collaborative care, patients were categorized into four mutually exclusive TFP groups: TFP not discussed; TFP discussed, declined; TFP discussed, did not decline; and TFP initiated. We conducted semistructured interviews with 43 unique patients and 58 unique providers (i.e., care managers and mental health specialists). Almost half (48.6%) of the veterans had no documentation of discussing TFP with their care manager; another 28.9% discussed it but declined. Most veterans (77.1%) had an encounter with a mental health specialist, 36.8% of whom never discussed TFP, and 35.7% of whom discussed it but declined. Providers reported that many veterans were not able, willing, or ready to engage in TFP and that non-trauma-focused therapies were better aligned with their treatment goals. Veterans gave numerous reasons for not initiating TFP, including having bad prior experiences with TFP and wanting to avoid thinking about past traumatic experiences. Commonly cited reasons for noninitiation were providers never discussing TFP with veterans and veterans declining TFP after discussing it with their provider. Interventions, such as shared decision-making tools, may be needed to engage providers and patients in informed discussions about TFP.

Retention rates in higher education continue to be a prevalent issue especially for community colleges and will become a bigger issue in the current climate of enrollment loss. Much literature regarding student retention focuses on broad, overarching findings, but it is important to understand institution-specific retention factors. The purpose of this study was to explore the characteristics of students who were not retained and gain their unique perspective on the factors that contributed to their attrition. This study took place at one community college in the Great Plains region of the United States utilizing a three-tiered mixed-methods analysis. Methods included quantitative analysis, survey techniques, and narrative inquiry. The study identified factors that were both positively and negatively correlated with retention. There were trends across different groups and their reasons for leaving the college before completing their goals and the factors were often interconnected and complex.

Heart attacks (HAs) present clinically with varying symptoms, which are not always described by patients as chest pain (CP) or chest discomfort (CD). Emergency Medical Dispatchers (EMDs) select the CP/CD dispatch protocol for non-chest pain HA symptoms or classic HA complaint of CP/CD. Nevertheless, it is still unknown how often callers report HA symptoms other than CP/CD. The objective of this study was to characterize the caller's descriptions of the primary HA symptoms, descriptions of the other HA symptoms, and the use of a case entry (CE) question clarifier. A retrospective descriptive study analyzed randomly selected EMD audios (where CD/CD protocol was used) from five accredited emergency communication centers in the United States. Several Quality Performance Review (QPR) experts reviewed the audios and recorded callers' initial problem descriptions, the use of and responses to the CE question clarifier, including the EMD-assigned final determinant code. A total of 1,261 audios were reviewed. The clarifier was used only 8.5% of the time. The CP/CD symptoms were mentioned alone or with other problems 87.0% of the time. Overall, CP symptom was mentioned alone 70.8%, HA alone 4.0%, and CD symptom alone 1.4% of the time. 9-1-1 callers report potential HA cases using a variety of terms and descriptions-most commonly CP. Other less-common symptoms associated with a HA may be mentioned. Therefore, EMDs must be well-trained to be prepared to probe the caller with a clarifying query to elicit more specific information when "having a heart attack" is the only complaint initially mentioned.

Nesting territories of great-horned owls (Bubo virginianus) and red-tailed hawks (Buteo jamaicensis) frequently overlap, with the owls using nests of other raptors. Records of use over a 22-year period in one locality were used to distinguish nesting sites used exclusively by great-horned owls, exclusively by red-tailed hawks, and those used by both. To determine the occurrence of various landscape characteristics within the proximity of a nest structure, I measured the total area of various land use types, total perimeter length, and the size of patches across six different land use types i.e., agriculture, pasture, residential, tree, pond, and roadside within circular plots around nests used by breeding pairs. The landscape features surrounding nests of great-horned owls differed from those surrounding red-tailed hawk nests in total perimeter length and size of patch. These differences are consistent with the fact that great-horned owls hunt from perches primarily at night using sensory modalities different than diurnal hunting red-tailed hawks.

Gel electrophoresis is the single most important molecular biology technique and it is central to life sciences research, but it is often too expensive for the secondary science classroom or homeschoolers. A simple safe low-cost procedure is described here that uses household materials to construct and run DNA gel electrophoresis. Plastic containers are fitted with aluminum foil electrodes and 9-V batteries to run food-grade agar-agar gels using aquarium pH buffers and then stained with gentian violet. This activity was tested in a high school biology classroom with significantly positive responses on postactivity reflective surveys. The electrophoresis activity addresses several Life Science Content Standard C criteria, including aspects of cell biology, genetics, and evolution. It also can be used to teach aspects of motion and force in the physical science classroom.

An algorithm for computing the normalized Hermite Functions, h n (x) in floating point arithmetic is presented. The algorithm is based on an efficient numerical evaluation of certain closed contour integrals in the complex plane. For large degree n, the algorithm is significantly faster than the O(n) complexity of the well known three term recurrence relation. Comparable accuracy is achieved in no more than $O(\sqrt{n})$ operations, and for arguments bounded away from $\pm \sqrt {2n}$ , only $O(\sqrt{\ln{n}})$ operations.

We propose a model for the effect of sedimentary basin depth on long‐period response spectra. The model is based on the analysis of 3‐D numerical simulations (finite element and finite difference) of long‐period (2–10 s ) ground motions for a suite of sixty scenario earthquakes (Mw 6.3 to Mw 7.1) within the Los Angeles basin region. We find depth to the 1.5 km/s S ‐wave velocity isosurface to be a suitable predictor variable, and also present alternative versions of the model based on depths to the 1.0 and 2.5 km/s isosurfaces. The resulting mean basin‐depth effect is period dependent, and both smoother (as a function of period and depth) and higher in amplitude than predictions from local 1‐D models. The main requirement for the use of the results in construction of attenuation relationships is determining the extent to which the basin effect, as defined and quantified in this study, is already accounted for implicitly in existing attenuation relationships, through (1) departures of the average “rock” site from our idealized reference model, and (2) correlation of basin depth with other predictor variables (such as V s 30 ).

RETURN TO ISSUEPREVLetterNEXTLETTERSRICHARD W. HARRALView Author Information El Dorado, ArkCite this: Chem. Eng. News 2006, 84, 13, 3–6Publication Date (Print):March 27, 2006Publication History Published online14 November 2010Published inissue 27 March 2006https://doi.org/10.1021/cen-v084n013.p003Copyright © 2006 AMERICAN CHEMICAL SOCIETYArticle Views79Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (2 MB) SUBJECTS:Materials,Wastes Get e-Alerts