Numerical investigation of aeroelastic mode distribution for aircraft wing model in subsonic air flow

In this paper, the numerical results on two problems originated in aircraft wing modeling have been presented. The first problem is concerned with the approximation to the set of the aeroelastic modes, which are the eigenvalues of a certain boundary-value problem. The affirmative answer is given to the following question: can the leading asymptotical terms in the analytical formulas be used as reasonably accurate description of the aeroelastic modes? The positive answer means that these leading terms can be used by engineers for practical calculations. The second problem is concerned with the flutter phenomena in aircraft wings in a subsonic, incompressible, inviscid air flow. It has been shown numerically that there exists a pair of the aeroelastic modes whose behavior depends on a speed of an air flow. Namely, when the speed increases, the distance between the modes tends to zero, and at some speed that can be treated as the flutter speed these two modes merge into one double mode

The Learning Styles of Undergraduate Students in CM Bachelor’s Degree Programs in the U.S.

This article presents the findings of a study analyzing the learning styles of undergraduate construction management (CM) students in bachelor’s degree programs in the United States. The study utilized the Felder-Silverman model and the Index of Learning Styles (ILS) as a survey instrument. The survey population consisted of 1,069 CM students from 36 university CM programs across the Associated Schools of Construction regions. Demographic information, the raw ILS responses, and the ILS web-based survey report were collected from the students. The results were analyzed and compared to both the CM students themselves and to similar studies done with engineering students. It was found that CM students were visual, active, sensing, and sequential learners. This study provides recommendations for how CM instructors might align their teaching styles with CM-student learning styles, and discusses impacts on the CM industry

A high-throughput screen identifying sequence and promiscuity characteristics of the loxP spacer region in Cre-mediated recombination

BACKGROUND: Cre-loxP recombination refers to the process of site-specific recombination mediated by two loxP sequences and the Cre recombinase protein. Transgenic experiments exploit integrative recombination, where a donor plasmid carrying a loxP site and DNA of interest integrate into a recipient loxP site in a target genome. Unfortunately, integrative recombination is highly inefficient because the insert is flanked by two loxP sites, which themselves become targets for Cre and lead to subsequent excision of the insert. A small number of mutations have been discovered in parts of the loxP sequence, specifically the spacer and inverted repeat segments, that increase the efficiency of integrative recombination. In this study we introduce a high-throughput in vitro assay to rapidly detect novel loxP spacer mutants and describe the sequence characteristics of successful recombinants. RESULTS: We created synthetic loxP oligonucleotides that contained a combination of inverted repeat mutations (the lox66 and lox71 mutations) and mutant spacer sequences, degenerate at 6 of the 8 positions. After in vitro Cre recombination, 3,124 recombinant clones were identified by sequencing. Included in this set were 31 unique, novel, self-recombining sequences. Using network visualization tools, we recognized 12 spacer sets with restricted promiscuity. We observed that increased guanine content at all spacer positions save for position 8 resulted in increased recombination. Interestingly, recombination between identical spacers was not preferred over non-identical spacers. We also identified a set of 16 pairs of loxP spacers that reacted at least twice with another spacer, but not themselves. Further, neither the wild-type P1 phage loxP sequence nor any of the known loxP spacer mutants appeared to be kinetically favoured by Cre recombinase. CONCLUSION: This study approached loxP spacer mutant screening in an unbiased manner, assuming nothing about candidate loxP sites save for the conserved 4 and 5 spacer positions. Candidate sites were free to recombine with any other sequence in the pool of all possible sites. The subset of loxP sites identified here are candidates for in vivo serial recombination as they have already demonstrated limited promiscuity with other loxP spacer and stability in the presence of Cre

The Design and Operation of The Keck Observatory Archive

The Infrared Processing and Analysis Center (IPAC) and the W. M. Keck Observatory (WMKO) operate an archive for the Keck Observatory. At the end of 2013, KOA completed the ingestion of data from all eight active observatory instruments. KOA will continue to ingest all newly obtained observations, at an anticipated volume of 4 TB per year. The data are transmitted electronically from WMKO to IPAC for storage and curation. Access to data is governed by a data use policy, and approximately two-thirds of the data in the archive are public.Comment: 12 pages, 4 figs, 4 tables. Presented at Software and Cyberinfrastructure for Astronomy III, SPIE Astronomical Telescopes + Instrumentation 2014. June 2014, Montreal, Canad

The X-ray Remnant of SN1987A

We present high resolution Chandra observations of the remnant of SN1987A in the Large Magellanic Cloud. The high angular resolution of the Chandra X-ray Observatory (CXO) permits us to resolve the X-ray remnant. We find that the remnant is shell-like in morphology, with X-ray peaks associated with some of the optical hot spots seen in HST images. The X-ray light curve has departed from the linear flux increase observed by ROSAT, with a 0.5-2.0 keV luminosity of 1.5 x 10^35 erg/s in January 2000. We set an upper limit of 2.3 x 10^34 ergs/s on the luminosity of any embedded central source (0.5 - 2 keV). We also present a high resolution spectrum, showing that the X-ray emission is thermal in origin and is dominated by highly ionized species of O, Ne, Mg, and Si.Comment: 16 pages, 3 figures, Accepted for publication in ApJ Letter

Prospectus, August 21, 2013

OBAMA SIGNS STUDENT LOAN DEAL; States tightening rules on college loans; College survival guide money matters: How to survive your first year on campus - without going broke; Essential skills for college freshmen; Boosting inclusion on campus; Are humans hard-wired for racial prejudice?; Tanney\u27s shot at the real thinghttps://spark.parkland.edu/prospectus_2013/1009/thumbnail.jp

Assessing Causes of Change in the Freshwater Mussels (Bivalvia: Unionidae) in the Black River, Ohio

Habitat destruction is believed to be the number one cause of the decline in unionid mussels. Around the world, cities, towns and agriculture alter the structure of watersheds, and the Black River in Ohio may be a typical example. We investigated the diversity and abundance of unionid mussels in this watershed and compared results to urbanization locations, to site-specific appearance of the habitat and to a 1997 fish survey, as host species are another factor important to the distribution of unionid mussels. Although shells were found for 21 species, only 11 of these species were found alive. Seven of the species represented only by shells occurred only in the urbanized lower main stem of the river and less than five shells were found for each. Most of these shells were old and worn. Furthermore, the present assemblage in the main stem varied from shells obtained at a nearby archeological site, and from a voucher set of species obtained at the turn of the 20th Century. Mussel communities higher in the river and those in tributaries were less diverse, but abundance of the species present was higher than in the main stem. A lack of fish hosts may limit mussel diversity, as hosts for several species present in the main stem do not reside higher in the watershed. Overall, mussel assemblages in the Black River appear typical for the region with relatively abundant, but low diversity communities upstream of the cities that line Lake Erie\u27s coast and diverse, but small and potentially threatened, populations in the urban regions

Communication Between Health Care Providers and At-Risk Mothers: Perceptions and Practices

Background This study examined knowledge, attitudes and opinions regarding alcohol, tobacco, and other drug (ATOD) use during pregnancy among women enrolled in drug treatment centers. It also assessed the educational and screening practices of health care professionals who care for women of child-bearing age in Utah. Methods The assessment of ATOD use was based on a convenience sample of women who were enrolled in drug treatment centers in Utah. The sample (n = 60) was surveyed by trained research team members. The assessment of screening practices of physicians and other medical professionals (n = 350) who deal with women’s obstetric and gynecological conditions was conducted via an online survey. An in-depth interview with seven of the professionals was also conducted. Results Most women surveyed (72%) reported that they would follow the advice of their health care provider regarding the use of alcohol, tobacco and other drugs (ATOD). Other sources of information (e.g. TV, Internet and radio) were less trusted. The women also indicated that a major barrier to disclosing an ATOD use was fear of negative consequences, both legal and social. Analysis of data from the professionals surveyed indicated that while most do some screening, there is a significant difference in ATOD screening practices for pregnant women and for women who are of childbearing age but not pregnant. Further, while nearly all professionals reported educating women who came to their clinic, fewer than 35% indicated using written educational materials. Lack of time was indicated as the primary barrier to proper screening and education of women in health care clinics. Conclusion Women who have been enrolled in treatment centers for ATOD addictions are fearful of the negative legal and social repercussions as a result of their ATOD use and hence do not consistently seek prenatal care. However, when information is given, most women are willing to comply with the recommendations of their health care providers. Providers are also very interested in quality patient care, but indicate that lack of time does not allow adequate one-on-one time with each patient. Screening and educational practices are performed in most offices, but both the timing of the screening and approach to patient education may not be sufficient to ensure optimal outcomes