207 research outputs found

    Instructor Use of Tablet PCs in a College Pre-Calculus Course: Implementation & Assessment

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    A group of six math instructors used tablet PCs to teach their individual sections of a high enrollment gateway Pre-Calculus course in a diverse urban four-year college. Student performance in the experimental sections were compared to those in 31 other sections in terms of student retention, pass rates, and score on the department-wide standardized final exam. Student performance was higher in Tablet PC sections across all three measures, although in some cases the improvement was not substantial enough to improve students’ overall course grades. Surveys of students and faculty in classes using a Tablet PC reflected overall positive impressions of the technology’s use in mathematics classrooms

    U.S. Nuclear Weapons Complex: Y-12 and Oak Ridge National Laboratory at High Risk

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    Since POGO\u27s original report in 2001, U.S. Nuclear Weapons Complex: Security at Risk, the organization\u27s continuing investigations\u27 have documented how a variety of U.S. nuclear facilities have not implemented adequate protections against these threats, even when the facilities have large stashes of weapons-grade and weapons-quantity nuclear materials which particularly merit protection. This report more specifically documents the shortcomings of efforts to secure Y-12 and Oak Ridge National Laboratory (ORNL). An initial examination of these sites was reported in POGO\u27s May 2005 study, U.S. Nuclear Weapons Complex: Homeland Security Opportunities . That report presented the findings of POGO\u27s investigation into security at facilities throughout the nuclear weapons complex, and concluded that consolidating weapons-grade nuclear materials from 13 sites to seven sites would dramatically increase security, as well as save the DOE an estimated $3 billion in security costs over three years. This research was completed money allocated during Round 6 of the Citizens’ Monitoring and Technical Assessment Fund (MTA Fund). Clark University was named conservator of these works. If you have any questions or concerns please contact us at [email protected]://commons.clarku.edu/pogo/1000/thumbnail.jp

    Automated, Ultra-Sterile Solid Sample Handling and Analysis on a Chip

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    There are no existing ultra-sterile lab-on-a-chip systems that can accept solid samples and perform complete chemical analyses without human intervention. The proposed solution is to demonstrate completely automated lab-on-a-chip manipulation of powdered solid samples, followed by on-chip liquid extraction and chemical analysis. This technology utilizes a newly invented glass micro-device for solid manipulation, which mates with existing lab-on-a-chip instrumentation. Devices are fabricated in a Class 10 cleanroom at the JPL MicroDevices Lab, and are plasma-cleaned before and after assembly. Solid samples enter the device through a drilled hole in the top. Existing micro-pumping technology is used to transfer milligrams of powdered sample into an extraction chamber where it is mixed with liquids to extract organic material. Subsequent chemical analysis is performed using portable microchip capillary electrophoresis systems (CE). These instruments have been used for ultra-highly sensitive (parts-per-trillion, pptr) analysis of organic compounds including amines, amino acids, aldehydes, ketones, carboxylic acids, and thiols. Fully autonomous amino acid analyses in liquids were demonstrated; however, to date there have been no reports of completely automated analysis of solid samples on chip. This approach utilizes an existing portable instrument that houses optics, high-voltage power supplies, and solenoids for fully autonomous microfluidic sample processing and CE analysis with laser-induced fluorescence (LIF) detection. Furthermore, the entire system can be sterilized and placed in a cleanroom environment for analyzing samples returned from extraterrestrial targets, if desired. This is an entirely new capability never demonstrated before. The ability to manipulate solid samples, coupled with lab-on-a-chip analysis technology, will enable ultraclean and ultrasensitive end-to-end analysis of samples that is orders of magnitude more sensitive than the ppb goal given in the Science Instruments

    Design and Development of Alternative Vectorthotic Insole: Technical Report

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    This CVF funded product design and development project for orthotic range aspires to be as effective as a functional foot orthotic. It is adaptable and customisable to meet the needs of the busy clinical environment as an off the shelf solution. Healthy Step has a successful foot orthotics and rehabilitation range. There is a growing area of business in the private market and internet sales. There is a perceived opportunity to develop a new brand of devices based upon the existing range that: • Exude quality and performance – and would therefore carry a higher price point • Are only available to clinics and clinicians – allowing clinics to set their own prices and be unaffected by Healthy Step’s direct to patient internet sales. • Are not available direct to the patients. • Focus on the business aspirations of the clinician and/or their practice. • Allowing them to realise greater profit by “selling”/prescribing quality, branded, performance devices that deliver adaptable clinical treatments with a quality retail feel and offering. Heel, ball and arch orthotic components of the existing vectorthotic were improved during the this project. Completion was a great live experience for the team although some issue with the printing tolerances as it had an impact on the first phase of iterations especially the snap fit parts of the orthotic but with product testing and feedback from the client these were overcome. The project resulted the company investing in a mid range 3D printing device and relevant software & hardware,an a placement student. They also start offering customized products and bespoke 3D printing services to their customers

    Snow algae communities in Antarctica: metabolic and taxonomic composition.

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    Snow algae are found in snowfields across cold regions of the planet, forming highly visible red and green patches below and on the snow surface. In Antarctica, they contribute significantly to terrestrial net primary productivity due to the paucity of land plants, but our knowledge of these communities is limited. Here we provide the first description of the metabolic and species diversity of green and red snow algae communities from four locations in Ryder Bay (Adelaide Island, 68°S), Antarctic Peninsula. During the 2015 austral summer season, we collected samples to measure the metabolic composition of snow algae communities and determined the species composition of these communities using metabarcoding. Green communities were protein-rich, had a high chlorophyll content and contained many metabolites associated with nitrogen and amino acid metabolism. Red communities had a higher carotenoid content and contained more metabolites associated with carbohydrate and fatty acid metabolism. Chloromonas, Chlamydomonas and Chlorella were found in green blooms but only Chloromonas was detected in red blooms. Both communities also contained bacteria, protists and fungi. These data show the complexity and variation within snow algae communities in Antarctica and provide initial insights into the contribution they make to ecosystem functioning.European Union (project no. 215G) INTERREG IVB ‘Energetic Algae’ (EnAlgae) program and a Leverhulme Trust Research Grant (RPG-2017-077

    A touchdown nucleic acid amplification protocol as an alternative to culture backup for immunofluorescence in the routine diagnosis of acute viral respiratory tract infections

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    BACKGROUND: Immunofluorescence and virus culture are the main methods used to diagnose acute respiratory virus infections. Diagnosing these infections using nucleic acid amplification presents technical challenges, one of which is facilitating the different optimal annealing temperatures needed for each virus. To overcome this problem we developed a diagnostic molecular strip which combined a generic nested touchdown protocol with in-house primer master-mixes that could recognise 12 common respiratory viruses. RESULTS: Over an 18 month period a total of 222 specimens were tested by both immunofluorescence and the molecular strip. The specimens came from 103 males (median age 3.5 y), 80 females (median age 9 y) and 5 quality assurance scheme specimens. Viruses were recovered from a number of specimen types including broncho-alveolar lavage, nasopharyngeal secretions, sputa, post-mortem lung tissue and combined throat and nasal swabs. Viral detection by IF was poor in sputa and respiratory swabs. A total of 99 viruses were detected in the study from 79 patients and 4 quality control specimens: 31 by immunofluorescence and 99 using the molecular strip. The strip consistently out-performed immunofluorescence with no loss of diagnostic specificity. CONCLUSIONS: The touchdown protocol with pre-dispensed primer master-mixes was suitable for replacing virus culture for the diagnosis of respiratory viruses which were negative by immunofluorescence. Results by immunofluorescence were available after an average of 4–12 hours while molecular strip results were available within 24 hours, considerably faster than viral culture. The combined strip and touchdown protocol proved to be a convenient and reliable method of testing for multiple viruses in a routine setting

    Using environmental monitoring to complement in-depth qualitative interviews in cold homes research

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    Cold homes contribute to twenty to forty thousand excess winter deaths each year in the UK and approximately 300,000 hospital admissions. Using fuel poverty as an identifier for those at risk does not always capture everyday exposure to cold homes due to variations in financial trade-offs and behavioural factors. Few fuel poverty studies have combined environmental measurements with qualitative data on lived experiences of fuel poverty and cold homes. This paper looks at the strengths and limitations of using a mixed method, environmental and qualitative interviewing approach. A series of six discreet studies were conducted between 2001 and 2015 using a similar methodology with a mixed methods design where in-depth interviews were conducted alongside temperature and humidity measurements. The research studies found that combining environmental monitoring with qualitative research methods allows both cross validation and triangulation of data in order to provide a richer and more insightful examination into the lives of people living in cold homes. The studies demonstrate how a combined methodological approach can help explain the choices, decisions and behaviour of households experiencing cold homes and fuel poverty. The paper concludes with recommendations for future development and implementation of the research method

    Constraints on the Progenitor System of the Type Ia Supernova SN 2011fe/PTF11kly

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    Type Ia supernovae (SNe) serve as a fundamental pillar of modern cosmology, owing to their large luminosity and a well-defined relationship between light-curve shape and peak brightness. The precision distance measurements enabled by SNe Ia first revealed the accelerating expansion of the universe, now widely believed (though hardly understood) to require the presence of a mysterious "dark" energy. General consensus holds that Type Ia SNe result from thermonuclear explosions of a white dwarf (WD) in a binary system; however, little is known of the precise nature of the companion star and the physical properties of the progenitor system. Here we make use of extensive historical imaging obtained at the location of SN 2011fe/PTF11kly, the closest SN Ia discovered in the digital imaging era, to constrain the visible-light luminosity of the progenitor to be 10-100 times fainter than previous limits on other SN Ia progenitors. This directly rules out luminous red giants and the vast majority of helium stars as the mass-donating companion to the exploding white dwarf. Any evolved red companion must have been born with mass less than 3.5 times the mass of the Sun. These observations favour a scenario where the exploding WD of SN 2011fe/PTF11kly, accreted matter either from another WD, or by Roche-lobe overflow from a subgiant or main-sequence companion star.Comment: 22 pages, 6 figures, submitte
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