The radiating part of circular sources

An analysis is developed linking the form of the sound field from a circular source to the radial structure of the source, without recourse to far-field or other approximations. It is found that the information radiated into the field is limited, with the limit fixed by the wavenumber of source multiplied by the source radius (Helmholtz number). The acoustic field is found in terms of the elementary fields generated by a set of line sources whose form is given by Chebyshev polynomials of the second kind, and whose amplitude is found to be given by weighted integrals of the radial source term. The analysis is developed for tonal sources, such as rotors, and, for Helmholtz number less than two, for random disk sources. In this case, the analysis yields the cross-spectrum between two points in the acoustic field. The analysis is applied to the problems of tonal radiation, random source radiation as a model problem for jet noise, and to noise cancellation, as in active control of noise from rotors. It is found that the approach gives an accurate model for the radiation problem and explicitly identifies those parts of a source which radiate.Comment: Submitted to Journal of the Acoustical Society of Americ

College of Health and Human Service Faculty’s Confidence and Inclusion of LGBTQ+ Health Content in Curriculum

In the health care system, those who identify as lesbian, gay, bisexual, transgender, queer, (LGBTQ+) face discrimination and health disparities. Students who are better prepared in higher education to provide care for this population have higher levels of confidence in LGBTQ+ health content than those who have less exposure. Therefore, faculty who teach curriculum related to health and wellness have an opportunity to prepare students to provide high quality, patient centered care by teaching culturally competent care that is inclusive of LGBTQ+ populations. The aim of the study is to determine whether the degree of confidence in teaching LGBTQ+ health content is related to the implementation of LGBTQ+ health content into health care faculty curriculum. Faculty from the University of New Hampshire College of Health and Human Services and Department of Psychology were surveyed to address the proposed research aim. The results were descriptive and correlational analyses. We found that there is statistically significant positive correlation between faculty’s confidence of LGBTQ+ health content and their inclusion of this material in the curriculum (r = .56 & r = .72, p\u3c 0.05). Our findings indicate that increasing confidence among faculty may increase their inclusion of the content in the curriculum

Cytotoxic Activity of Hexane Extracts of Psidium guajava L (Myrtaceae) and Cassia alata L (Caesalpineaceae) in Kasumi-1 and OV2008 Cancer Cell Lines

Purpose: The cytotoxic effects of hexane extracts of Cassia alata and Psidium guajava leaves were evaluated in OV2008 ovarian and Kasumi-1 leukemia cancer cell lines, respectively.Methods: The cancer cells were exposed to various concentrations of either C. alata (100 – 180 μg/ml) or P. guajava (100 – 500 μg/ml) leaf extract for 24 h. Following treatment, the cells were evaluated using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to determine the cytotoxic effect of the extracts. C. alata extract was also analyzed using high performance liquid chromatography (HPLC).Results: C. alata and P. guajava extracts produced significant (p < 0.05) cytotoxicity in OV2008 and Kasumi-1 cell lines, respectively. The IC50 values were 160 μg/ml for C. alata and 200 μg/ml for P guajava. Further, the cytotoxicity exhibited by C. alata might be attributable to the flavonoid, kaempferol, which was identified as a constituent of the extract.Conclusion: The results suggest that further chemical analysis and mechanistic investigations should be conducted on P. guajava and C. alata extracts to validate their potential uses for anticancer therapy.Keywords: P. guajava, C. alata, Cytotoxicity, Kasumi-1, Cancer cell, OV200

Prevention of Sepsis in Children: A New Paradigm for Public Policy

Sepsis is one of the leading causes of death worldwide. While the management of critically ill patients with sepsis is certainly better now compared to 20 years ago, sepsis-associated mortality remains unacceptably high. Annual deaths from sepsis in both children and adults far surpass the number of deaths from acute myocardial infarction (AMI), stroke, or cancer. Given the substantial toll that sepsis takes worldwide, prevention of sepsis remains a global priority. Multiple effective prevention strategies exist. Antibiotic prophylaxis, immunizations, and healthcare quality improvement initiatives are important means through which we may reduce the morbidity and mortality from sepsis around the world. Inclusion of these strategies in a coordinated and thoughtful campaign to reduce the global burden of sepsis is necessary for the improvement of pediatric health worldwide

Inversion of spinning sound fields

A method is presented for the reconstruction of rotating monopole source distributions using acoustic pressures measured on a sideline parallel to the source axis. The method requires no \textit{a priori} assumptions about the source other than that its strength at the frequency of interest vary sinusoidally in azimuth on the source disc so that the radiated acoustic field is composed of a single circumferential mode. When multiple azimuthal modes are present, the acoustic field can be decomposed into azimuthal modes and the method applied to each mode in sequence. The method proceeds in two stages, first finding an intermediate line source derived from the source distribution and then inverting this line source to find the radial variation of source strength. A far-field form of the radiation integrals is derived, showing that the far field pressure is a band-limited Fourier transform of the line source, establishing a limit on the quality of source reconstruction which can be achieved using far-field measurements. The method is applied to simulated data representing wind-tunnel testing of a ducted rotor system (tip Mach number~0.74) and to control of noise from an automotive cooling fan (tip Mach number~0.14), studies which have appeared in the literature of source identification.Comment: Revised version of paper submitted to JASA; five more figures; expanded content with more discussion of error behaviour and relation to Nearfield Acoustical Holograph

Global Maps of Science based on the new Web-of-Science Categories

In August 2011, Thomson Reuters launched version 5 of the Science and Social Science Citation Index in the Web of Science (WoS). Among other things, the 222 ISI Subject Categories (SCs) for these two databases in version 4 of WoS were renamed and extended to 225 WoS Categories (WCs). A new set of 151 Subject Categories (SCs) was added, but at a higher level of aggregation. Since we previously used the ISI SCs as the baseline for a global map in Pajek (Rafols et al., 2010) and brought this facility online (at http://www.leydesdorff.net/overlaytoolkit), we recalibrated this map for the new WC categories using the Journal Citation Reports 2010. In the new installation, the base maps can also be made using VOSviewer (Van Eck & Waltman, 2010).Comment: Scientometrics, in pres

Business Programs in Study Abroad: a Reconsideration

In acknowledgement of the importance of fostering a global perspective in their students, business educators stress the role that international study can play in increasing interpersonal skills and also broadening knowledge of global business practices. Traditionally offered as semester- or year- long programs, today’s study abroad programs are more often short-term in nature, raising questions about student outcomes of abbreviated study tours. This longitudinal study of students who participated over a nine-year period examines the benefits and limitations of short-term study tours. Results suggest that schools of business may want to think again about desired student outcomes and learning objectives and whether these can be accomplished in a compressed time frame

Predictors of Enrolling in Online Courses: An Exploratory Study of Students in Undergraduate Marketing Courses

An exploratory study of undergraduate students enrolled in marketing courses at a Southeastern regional university was conducted to determine the motivations and characteristics of marketing students who plan to be online learners and examined for differences between those who have taken and those who have not taken online classes. An online survey of Likert scales, openended questions and demographic questions was sent via class learning management websites. A total of 165 students of the 438 invited to participate completed the survey. A structural model was developed using SMART-PLS to estimate the relationships of constructs that predict taking online courses. Results of the study showed differences in predictors of those that have taken online courses compared to those who plan on taking online courses. A significant predictor of those planning on taking online courses is quality of learning while a significant predictor of those who have taken online courses is scheduling and timing. The results can be used to examine ways to improve/enhance the student’s educational experience, as well as an institution’s effectiveness in attracting the growing body of online learners