24,452 research outputs found

    Value added or misattributed? A multi-institution study on the educational benefit of labs for reinforcing physics content

    Full text link
    Instructional labs are widely seen as a unique, albeit expensive, way to teach scientific content. We measured the effectiveness of introductory lab courses at achieving this educational goal across nine different lab courses at three very different institutions. These institutions and courses encompassed a broad range of student populations and instructional styles. The nine courses studied had two key things in common: the labs aimed to reinforce the content presented in lectures, and the labs were optional. By comparing the performance of students who did and did not take the labs (with careful normalization for selection effects), we found universally and precisely no added value to learning from taking the labs as measured by course exam performance. This work should motivate institutions and departments to reexamine the goals and conduct of their lab courses, given their resource-intensive nature. We show why these results make sense when looking at the comparative mental processes of students involved in research and instructional labs, and offer alternative goals and instructional approaches that would make lab courses more educationally valuable.Comment: Accepted to Phys Rev PE

    Interaction of gases with lunar materials

    Get PDF
    The surface chemistry of Apollo 17 lunar fines samples 74220 (the orange soil) and 74241 (the gray control soil) has been studied by measuring the adsorption of nitrogen, argon, and oxygen (all at 77 K) and also water vapor (at 20 or 22 C). In agreement with results for samples from other missions, both samples had low initial specific surface areas, consisted of nonporous particles, and were attacked by water vapor at high relative pressure to give an increased specific surface area and create a pore system which gave rise to a capillary condensation hysteresis loop in the adsorption isotherms. In contrast to previous samples, both of the Apollo 17 soils were partially hydrophobic in their initial interaction with water vapor (both samples were completely hydrophilic after the reaction with water). The results are consistent with formation at high temperatures without subsequent exposure to significant amounts of water

    Interaction of gases with lunar materials

    Get PDF
    Quantitative efforts to assess the surface properties of lunar fines, particularly water induced porosity are discussed. Data show that: (1) changes induced in lunar fines are not visible in high energy electron micrographs, (2) scanning micrographs show no change in particle size distribution as a result of reaction with water, (3) water induced changes are internal to the particles themselves, (4) normal laboratory atmosphere blocks alteration reaction with water, and (5) surface properties of mature lunar soils appear to be almost independent of chemical composition and mineralogy, but there are some variations in their reactivity toward water

    Design and Maintenance of Cisterns

    Get PDF
    I. Design concepts: (See Figure 1) Water tight inside and outside Power & Machinery Manhole or other covers tight to prevent contamination with 2 raised curb Overflow with check valve Initial roof-off diverted from cistern as roof dirt is washed off Inlet pipe near the top with splash pan below or a force breaker at bottom so that floor settlements are not disturbed. No data on which is more effective. Cleanout outlet pipe to pump located in small sump area with floor sloping to sump. Placed below ground to prevent freezing Water pipe to houe from floating inlet or 4 off botto

    Behaviour change interventions to influence antimicrobial prescribing: a cross-sectional analysis of reports from UK state-of-the-art scientific conferences

    Get PDF
    Background To improve the quality of antimicrobial stewardship (AMS) interventions the application of behavioural sciences supported by multidisciplinary collaboration has been recommended. We analysed major UK scientific research conferences to investigate AMS behaviour change intervention reporting. Methods Leading UK 2015 scientific conference abstracts for 30 clinical specialties were identified and interrogated. All AMS and/or antimicrobial resistance(AMR) abstracts were identified using validated search criteria. Abstracts were independently reviewed by four researchers with reported behavioural interventions classified using a behaviour change taxonomy. Results Conferences ran for 110 days with >57,000 delegates. 311/12,313(2.5%) AMS-AMR abstracts (oral and poster) were identified. 118/311(40%) were presented at the UK’s infectious diseases/microbiology conference. 56/311(18%) AMS-AMR abstracts described behaviour change interventions. These were identified across 12/30(40%) conferences. The commonest abstract reporting behaviour change interventions were quality improvement projects [44/56 (79%)]. In total 71 unique behaviour change functions were identified. Policy categories; “guidelines” (16/71) and “service provision” (11/71) were the most frequently reported. Intervention functions; “education” (6/71), “persuasion” (7/71), and “enablement” (9/71) were also common. Only infection and primary care conferences reported studies that contained multiple behaviour change interventions. The remaining 10 specialties tended to report a narrow range of interventions focusing on “guidelines” and “enablement”. Conclusion Despite the benefits of behaviour change interventions on antimicrobial prescribing, very few AMS-AMR studies reported implementing them in 2015. AMS interventions must focus on promoting behaviour change towards antimicrobial prescribing. Greater focus must be placed on non-infection specialties to engage with the issue of behaviour change towards antimicrobial use

    Intranasal melanoma treated with radiation therapy in three dogs

    Get PDF
    Three dogs were investigated for chronic unilateral nasal discharge. In all cases CT imaging showed an intranasal mass causing turbinate lysis and no evidence of metastasis. Cytology in cases 1 (a 14-year-old neutered male crossbreed dog) and 2 (a five-year-old neutered male German Shepherd dog) demonstrated a pleomorphic cell population with variable intracellular pigment suspicious of melanocytic neoplasia. Histopathology with immunohistochemistry (Melan-A and vimentin, plus PNL-2 in one case) confirmed the diagnosis of melanoma in all dogs. All dogs were treated with megavoltage radiotherapy using linear accelerators. Cases 1 and 3 (a nine-year-old neutered female beagle dog) received a hypofractionated (4 Ă— 8 Gy) protocol and case 2 received a definitive (12 Ă— 4 Gy) protocol. Complete remission was demonstrated on repeat CT scan five months after diagnosis in case 1 and seven months in case 2. Stable disease was documented on CT at four months for case 3; however, clinical signs in this dog remained controlled for 10 months in total. Case 1 died of unrelated causes five months after diagnosis, case 2 was euthanased due to the development of seizures 13 months after diagnosis, and case 3 was lost to follow-up 12 months after diagnosis. Melanoma should be considered as a rare differential diagnosis for primary nasal neoplasia in the dog and radiation therapy can be used as effective local therapy

    Efficiency of cinch on brome grass control.

    Get PDF
    85GE34, 85A11, 85A12

    Seed set control. competition. Herbicide efficiency. Herbicide trials.

    Get PDF
    Seed set control 83M60 - Barley grass 83Na54 – Barley grass 83A4 – Rye grass 83N50 – Brome grass Competition 84A12 – Brome grass 84A10 – Silver grass 84A6 – Barley grass Herbicide efficiency 84A7 - Brome grass : Hoegrass pre-emergent Herbicide trials 84A11 – Barley grass : Glean mixture 84A13 – Barley grass : Isoproturon 84A15 – Brome grass : Glean mixtures 84A16 - Brome grass : Hoegrass, Donsanex, AC222293 84A9 – Silver grass : lsoproturon, Yield, trifulualin, AC222293, Dosanex 84A14 – Rye grass : Hoegrass following Glean 84A19 – SD-95481 : Grasses controlled 84A20 – CME12701 : Evaluation for grass control 84N24 – SD-95481 : Ryegrass control 84N25 - Ryegrass : Hoegrass preplant, Isoproturon, Dosanex 84N26 – Ryegrass : Isoproturon plus FR1078/

    Ryegrass, barley, wildoats, Isoproturon, Kerb, Glean, silver grass, brome trials, Hoegrass

    Get PDF
    1983 Summary – trials reported. 83ME48 - Ryegrass - Glean and Hoegrass 83ME68 A&B - Barley Grass - Glean, Bladex 83ME69 - Brome Grass - Herbicides 83ME70 - Barley Grass - Mixtures 83ME71 - Wildoats Herbicides 83ME72 - Timing Spraying Ryegrass 83ME73 - Isoproturon - Barley Grass 82BA46 - Kerb Residues 82N40 - Kerb Residues 83N38 - Glean on Oats 83N39 - Efficiency of SSH on Barley Grass 83N40 - Barley Grass Effect on Crop Density 83N41 - Silver Grass Competition 83N42 - Brome Control by SSH 0800 Affected by crop Density 83N43 - Silver Grass Herbicides 83N50 - Hoegrass Following Glean 83WH45 - Barley Grass-SSH 0860 Efficiency 83WH46 - Barley Grass - Crop Density 83WH47 - Silver Grass Competition with Wheat 83WH48 - Silver Grass Herbicides 83WH49 - Brome Grass Competition with Whea
    • …
    corecore