6,974 research outputs found
Quantitative Infrared Image Analysis Of Thermally-Thin Cellulose Surface Temperatures During Upstream and Downstream Microgravity Flame Spread from A Central Ignition Line
Surface view calibrated infrared images of ignition and flame spread over a thin cellulose fuel were obtained at 30 Hz during microgravity flame spread tests in the 10 second Japan Microgravity Center (JAMIC). The tests also used a color video of the surface view and color images of the edge view using 35 millimeter 1600 Kodak Ektapress film at 2 Hz. The cellulose fuel samples (50% long fibers from lumi pine and 50% short fibers from birch) were made with an area density of 60 grams per square meters. The samples were mounted in the center of a 12 centimeter wide by 16 centimeter tall flow duct that uses a downstream fan to draw the air through the flow duct. Samples were ignited after the experiment package was released using a straight hot wire across the center of the 7.5 centimeter wide by 14 centimeter long samples. One case, at 1 atmosphere 35%O2 in N2, at a forced flow of 10 centimeters per second, is presented here. In this case, as the test progresses, the single flame begins to separate into simultaneous upstream and downstream flames. Surface temperature profiles are evaluated as a function of time, and temperature gradients for upstream and downstream flame spread are measured. Flame spread rates from IR image data are compared to visible image spread rate data. IR blackbody temperatures are compared to surface thermocouple readings to evaluate the effective emissivity of the pyrolyzing surface. Preheat lengths are evaluated both upstream and downstream of the central ignition point. A surface energy balance estimates the net heat flux from the flame to the fuel surface along the length of the fuel
Interventions to Promote More Effective Balance-Recovery Reactions in Industrial Settings: New Perspectives on Footwear and Handrails
âChange-in-supportâ balance-recovery reactions that involve rapid stepping or reaching movements play a critical role in preventing falls. Recent geriatrics studies have led to new interventions to improve ability to execute these reactions effectively. Some of these interventions have the potential to reduce fall risk for younger persons working in industrial settings. In this paper, we review research pertaining to two such interventions: 1) balance-enhancing footwear insoles designed to improve stepping reactions, and 2) proximity-triggered handrail cueing systems designed to improve reach-to-grasp reactions. The insole has a raised ridge around the perimeter that is intended to improve balance control by providing increased stimulation of sensory receptors on the footsole in situations where loss of balance may be imminent. The cueing system uses flashing lights and/or verbal prompts to attract attention to the handrail and ensure that the brain registers its location, thereby facilitating more rapid and accurate grasping of the rail if and when sudden loss of balance occurs. Results to date support the efficacy of both interventions in geriatric populations. There is also some evidence that these interventions may improve balance control in younger persons; however, further research is needed to confirm their efficacy in preventing falls in industrial settings
Highly accurate dating of micrometre-scale baddeleyite domains through combined focused ion beam extraction and UâPb thermal ionization mass spectrometry (FIB-TIMS)
Rapamycin weekly maintenance dosing and the potential efficacy of combination sorafenib plus rapamycin but not atorvastatin or doxycycline in tuberous sclerosis preclinical models
BACKGROUND: Tuberous sclerosis complex (TSC) is an autosomal dominant tumor suppressor syndrome, characterized by hamartomatous growths in the brain, skin, kidneys, lungs, and heart, which lead to significant morbidity. TSC is caused by mutations in the TSC1 or TSC2 genes, whose products, hamartin and tuberin, form a tumor suppressor complex that regulates the PI3K/Akt/mTOR pathway. Early clinical trials show that TSC-related kidney tumors (angiomyolipomas) regress when treated with the mammalian target of rapamycin (mTOR) inhibitor, rapamycin (also known as sirolimus). Although side effects are tolerable, responses are incomplete, and tumor regrowth is common when rapamycin is stopped. Strategies for future clinical trials may include the investigation of longer treatment duration and combination therapy of other effective drug classes.
RESULTS: Here, we examine the efficacy of a prolonged maintenance dose of rapamycin in Tsc2+/- mice with TSC-related kidney tumors. Cohorts were treated with rapamycin alone or in combination with interferon-gamma (IFN-g). The schedule of rapamycin included one month of daily doses before and after five months of weekly doses. We observed a 94.5% reduction in kidney tumor burden in Tsc2+/- mice treated (part one) daily with rapamycin (8 mg/kg) at 6 months †age \u3c 7 months, (part 2) weekly with rapamycin (16 mg/kg) at 7 months †age \u3c 12 months, and (part 3) daily with rapamycin (8 mg/kg) at 12 months †age \u3c 13 months; but we did not observe any improvement with combination IFN-g plus rapamycin in this study. We also used a Tsc2-/- subcutaneous tumor model to evaluate other classes of drugs including sorafenib, atorvastatin, and doxycycline. These drugs were tested as single agents and in combination with rapamycin. Our results demonstrate that the combination of rapamycin and sorafenib increased survival and may decrease tumor volume as compared to rapamycin treatment alone while sorafenib as a single agent was no different than control. Atorvastatin and doxycycline, either as single agents or in combination with rapamycin, did not improve outcomes as compared with controls.
CONCLUSION: Our results indicate that prolonged treatment with low doses of mTOR inhibitors may result in more complete and durable TSC-related tumor responses, and it would be reasonable to evaluate this strategy in a clinical trial. Targeting the Raf/Mek/Erk and/or VEGF pathways in combination with inhibiting the mTOR pathway may be another useful strategy for the treatment of TSC-related tumors
Preparing the Next Generation of Science Teacher Educators: A Model for Developing PCK for Teaching Science Teachers
DOI:10.1007/s10972-008-9115-6 http://www.springerlink.com/content/a1j4p781335r2548/fulltext.pdfScience education doctoral programs often fail to address a critical pieceâthe explicit attention to the preparation of future science teacher educators. In this article, we argue that, in addition to developing skills and a knowledge base for research, doctoral students must be given the opportunity to observe, practice, and reflect on the pedagogical knowledge necessary to instruct science teachers. In particular, we contend that the construct of pedagogical content knowledge (PCK) can be adapted to the context of knowledge for teaching science teachers. We use the PCK construct to propose a model for the development of knowledge for teaching science teachers, grounded in our experiences as doctoral students and faculty mentors. We end by recommending a vision for doctoral preparation and a new standard to be included in the ASTE Professional Knowledge Standards for Science Teacher Educators
Methods or Madness: Preparing the Next Generation of Elementary Science Teacher Educators
This conference paper was presented at the Association for Science Teacher Education in Clearwater, FL in January 2007. Contains graphs and policy guidelines.In recent surveys of doctoral students in all fields (Fagen & Niebur, 2000; Nyquist & Woodford, 2000), respondents shared concerns that an overemphasis on research led to inadequate preparation for teaching, curricular planning, collegiality, and service. In one study (Davis & Fiske, 1999), 50% of respondents felt they received inadequate preparation as teaching assistants, and 59% felt that faculty in their programs did not emphasize the importance of teaching. A 2001 survey (Golde & Dore) indicated that most current doctoral students are primarily interested in becoming faculty members, even though most will not begin their careers in the types of institutions where they received their doctoral training. We often use such evidence to criticize our colleagues in the sciences about the inadequacies of their
doctoral programs in preparing the next generation of university science instructors. However, what happens when we look inward to examine doctoral programs in science education
Pharmacistsâ use of guidelines for the supply of non-prescription medicines: a cross-sectional survey
Objectives:
Guidelines support best practice for healthcare practice. In Australia, some non-prescription medicines are only accessible after consultation with a pharmacist and are known as Pharmacist Only medicines. Guidelines for providing some Pharmacist Only medicines are available, however, it is currently unknown if and how these guidelines are used in practice.//
The objective was to characterise pharmacistsâ, intern pharmacists and pharmacy studentsâ use of guidelines for Pharmacist Only medicines.//
Methods:
A cross-sectional electronic survey of Australian registered pharmacists, intern pharmacists and pharmacy students was administered in July 2020. Questions explored the participantsâ use of Pharmacist Only medicine guidelines (available both in print and online; available online only) in the preceding 12 months. Data were analysed descriptively (i.e. frequencies, percentages).//
Key findings:
In total, 574 eligible respondents completed the survey. Overall, 396 (69%) reported accessing the online and in-print guidelines in the previous 12 months with 185 (33%) accessing online-only guidelines. The guideline on emergency contraception was used the most out of all guidelines in the past 12 months (278, 48%). Overall, respondents reported accessing guidelines to update knowledge, check their practice reflected best practice and content familiarisation. Respondentsâ reasons for not accessing guidelines were due to respondents stating they did not need the information or that they had previously accessed the guidelines more than 12 months ago. These reasons varied between respondent groups.//
Conclusions:
Access and use of the Pharmacist Only medicines guidelines varied between pharmacists, interns and students. Further understanding of the influences of the use of these guidelines will help inform professional bodies on how best to develop guidelines to increase consistent use in practice and implement interventions to increase use./
Playing safe: Assessing the risk of sexual abuse to elite child athletes
Young athletes frequently suffer from being seen as athletes first and children second. This has consequences for their legal, civil and human rights as children (Kelly et al., 1995) and for the way in which sport organisations choose to intervene on their behalf to protect them from physical, psychological and sexual abuses (Brackenridge, 1994). Sport careers peak at different ages depending on the sport: in some, children as young as 12 or 13 may reach the highest levels of competitive performance; in others, full maturity as an athlete may come late into adulthood or even middle age. Recognition of this variation has given rise to the concept of âsport ageâ (Kirby, 1986) referring to sport-specific athlete development. This concept is of significance in helping to identify the developmental process in terms of athletic, rather than chronological, maturity. The risk of sexual abuse in sport, formerly ignored or denied, has now been documented in a number of studies, using both quantitative and qualitative methods (Kirby & Greaves, 1996; Brackenridge, 1997; Volkwein, 1996). Drawing on data from these studies and from the previous work on sport age and athletic maturation, this paper proposes a possible means of identifying and assessing relative risk of sexual abuse to elite young athletes in selected sports. The concept of a âstage of imminent achievementâ (SIA) is proposed as the period of peak vulnerability of young athletes to sexual abuse
Use of a reference text by pharmacists, intern pharmacists and pharmacy students: a national cross-sectional survey
Background:
Reference texts assist pharmacists by addressing knowledge gaps and enabling evidence-based decisions when providing patient care. It is unknown whether reference text utilisation patterns differ between pharmacists, intern pharmacists and pharmacy students. To describe and compare the self-reported use and perceptions of a reference text, namely the national formulary, by pharmacists, intern pharmacists and pharmacy students. //
Methods:
Registered pharmacists, intern pharmacists and pharmacy students living in Australia were surveyed in July 2020. The survey was electronic and self-administered. Questions considered self-reported use of a specific reference text in the preceding 12 months. //
Key findings:
There were 554 eligible responses out of 774 who commenced the survey: 430 (78%) pharmacists, 45 (8%) intern pharmacists and 79 (14%) pharmacy students. Most participants (529/554, 96%) reported historical use of the text, though pharmacists were significantly less likely than intern pharmacists and students to use it frequently (52/422, 12% versus 16/43, 37% versus 23/76, 30%, P < 0.001). Pharmacists (44%, 177/404) reported using the text as a tool to resolve a situation when providing a service or patient care (177/404, 44%) or as a teaching resource (150/404, 38%). In contrast, intern pharmacists and students most commonly use these to familiarise themselves with the contents (30/43, 70%; 46/76, 61%) or update their knowledge (34/43, 79%; 53/76, 70%). //
Conclusions:
Access and use patterns varied significantly across career stages. A broader understanding of the use of reference texts may help develop interventions to optimise the content and usability. Varying usage patterns across the groups may inform the tailoring of texts for future use
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