Dynamics of animal movement in an ecological context: dragonfly wing damage reduces flight performance and predation success.

PubMed

Combes, S A; Crall, J D; Mukherjee, S

2010-06-23

Much of our understanding of the control and dynamics of animal movement derives from controlled laboratory experiments. While many aspects of animal movement can be probed only in these settings, a more complete understanding of animal locomotion may be gained by linking experiments on relatively simple motions in the laboratory to studies of more complex behaviours in natural settings. To demonstrate the utility of this approach, we examined the effects of wing damage on dragonfly flight performance in both a laboratory drop-escape response and the more natural context of aerial predation. The laboratory experiment shows that hindwing area loss reduces vertical acceleration and average flight velocity, and the predation experiment demonstrates that this type of wing damage results in a significant decline in capture success. Taken together, these results suggest that wing damage may take a serious toll on wild dragonflies, potentially reducing both reproductive success and survival.

The differences in analysing strategy of viscosity experiment between freshmen and laboratory assistant

NASA Astrophysics Data System (ADS)

Anggrayni, S.; Mubarok, H.; Putri, N. P.; Suprapto, N.; Kholiq, A.

2018-03-01

The viscosity is defined by dimension of a fluid that resists the force tending to motive the fluid to flow. The aim of viscosity experiment is to determine the fluid viscosity coefficient value. By using graphical analysis, the result of oil viscosity coefficient value which performed by laboratory assistant showed: (1) 0.20 Pa.s using solid ball with accuracy 99.64% and (2) 0.21 Pa.s using smaller solid ball with accuracy 99.17%. Meanwhile, the result of oil viscosity coefficient value which performed by freshmen showed: (1) 0.44 Pa.s using solid ball with accuracy 87.85% and (2) 0.32 Pa.s using smaller solid ball with accuracy 89.84%. The differences result of the freshmen and assistant laboratory viscosity experiment are caused by the freshmen calculated the coefficient viscosity value without velocity correction factor and they used small range fluid so the times are not identified well.

Design and implementation of an internet-based electrical engineering laboratory.

PubMed

He, Zhenlei; Shen, Zhangbiao; Zhu, Shanan

2014-09-01

This paper describes an internet-based electrical engineering laboratory (IEE-Lab) with virtual and physical experiments at Zhejiang University. In order to synthesize the advantages of both experiment styles, the IEE-Lab is come up with Client/Server/Application framework and combines the virtual and physical experiments. The design and workflow of IEE-Lab are introduced. The analog electronic experiment is taken as an example to show Flex plug-in design, data communication based on XML (Extensible Markup Language), experiment simulation modeled by Modelica and control terminals' design. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

The effect of participation in an extended inquiry project on general chemistry student laboratory interactions, confidence, and process skills

NASA Astrophysics Data System (ADS)

Krystyniak, Rebecca A.

2001-12-01

This study explored the effect of participation by second-semester general chemistry students in an extended open-inquiry laboratory investigation on their use of science process skills and confidence in performing specific aspects of laboratory investigations. In addition, verbal interactions of a student lab team among team members and with their instructor over three open-inquiry laboratory sessions and two non-inquiry sessions were investigated. Instruments included the Test of Integrated Skills (TIPS), a 36-item multiple-choice instrument, and the Chemistry Laboratory Survey (CLS), a researcher co-designed 20-item 8-point instrument. Instruments were administered at the beginning and close of the semester to 157 second-semester general chemistry students at the two universities; students at only one university participated in open-inquiry activity. A MANCOVA was performed to investigate relationships among control and experimental students, TIPS, and CLS post-test scores. Covariates were TIPS and CLS pre-test scores and prior high school and college science experience. No significant relationships were found. Wilcoxen analyses indicated both groups showed increase in confidence; experimental-group students with below-average TIPS pre-test scores showed a significant increase in science process skills. Transcribed audio tapes of all laboratory-based verbal interactions were analyzed. Coding categories, developed using the constant comparison method, led to an inter-rater reliability of .96. During open-inquiry activities, the lab team interacted less often, sought less guidance from their instructor, and talked less about chemistry concepts than during non-inquiry activities. Evidence confirmed that students used science process skills and engaged in higher-order thinking during both types of activities. A four-student focus shared their experiences with open-inquiry activities, indicating that they enjoyed the experience, viewed it as worthwhile, and believed it helped them gain understanding of the nature of chemistry research. Research results indicate that participation in open-inquiry laboratory increases student confidence and, for some students, the ability to use science process skills. Evidence documents differences in student laboratory interactions and behavior that are attributable to the type of laboratory experience. Further research into aspects of open-inquiry laboratory experiences is recommended.

Integration of Video-Based Demonstrations to Prepare Students for the Organic Chemistry Laboratory

NASA Astrophysics Data System (ADS)

Nadelson, Louis S.; Scaggs, Jonathan; Sheffield, Colin; McDougal, Owen M.

2015-08-01

Consistent, high-quality introductions to organic chemistry laboratory techniques effectively and efficiently support student learning in the organic chemistry laboratory. In this work, we developed and deployed a series of instructional videos to communicate core laboratory techniques and concepts. Using a quasi-experimental design, we tested the videos in five traditional laboratory experiments by integrating them with the standard pre-laboratory student preparation presentations and instructor demonstrations. We assessed the influence of the videos on student laboratory knowledge and performance, using sections of students who did not view the videos as the control. Our analysis of pre-quizzes revealed the control group had equivalent scores to the treatment group, while the post-quiz results show consistently greater learning gains for the treatment group. Additionally, the students who watched the videos as part of their pre-laboratory instruction completed their experiments in less time.

Transitioning EEG experiments away from the laboratory using a Raspberry Pi 2.

PubMed

Kuziek, Jonathan W P; Shienh, Axita; Mathewson, Kyle E

2017-02-01

Electroencephalography (EEG) experiments are typically performed in controlled laboratory settings to minimise noise and produce reliable measurements. These controlled conditions also reduce the applicability of the obtained results to more varied environments and may limit their relevance to everyday situations. Advances in computer portability may increase the mobility and applicability of EEG results while decreasing costs. In this experiment we show that stimulus presentation using a Raspberry Pi 2 computer provides a low cost, reliable alternative to a traditional desktop PC in the administration of EEG experimental tasks. Significant and reliable MMN and P3 activity, typical event-related potentials (ERPs) associated with an auditory oddball paradigm, were measured while experiments were administered using the Raspberry Pi 2. While latency differences in ERP triggering were observed between systems, these differences reduced power only marginally, likely due to the reduced processing power of the Raspberry Pi 2. An auditory oddball task administered using the Raspberry Pi 2 produced similar ERPs to those derived from a desktop PC in a laboratory setting. Despite temporal differences and slight increases in trials needed for similar statistical power, the Raspberry Pi 2 can be used to design and present auditory experiments comparable to a PC. Our results show that the Raspberry Pi 2 is a low cost alternative to the desktop PC when administering EEG experiments and, due to its small size and low power consumption, will enable mobile EEG experiments unconstrained by a traditional laboratory setting. Copyright © 2016 Elsevier B.V. All rights reserved.

Sucrose acceptance and different forms of associative learning of the honey bee (apis mellifera L.) in the field and laboratory.

PubMed

Mujagic, Samir; Sarkander, Jana; Erber, Barbara; Erber, Joachim

2010-01-01

The experiments analyze different forms of learning and 24-h retention in the field and in the laboratory in bees that accept sucrose with either low (/=30% or >/=50%) concentrations. In the field we studied color learning at a food site and at the hive entrance. In the laboratory olfactory conditioning of the proboscis extension response (PER) was examined. In the color learning protocol at a feeder, bees with low sucrose acceptance thresholds (/=50%). Retention after 24 h is significantly different between the two groups of bees and the choice reactions converge. Bees with low and high acceptance thresholds in the field show no differences in the sucrose sensitivity PER tests in the laboratory. Acceptance thresholds in the field are thus a more sensitive behavioral measure than PER responsiveness in the laboratory. Bees with low acceptance thresholds show significantly better acquisition and 24-h retention in olfactory learning in the laboratory compared to bees with high thresholds. In the learning protocol at the hive entrance bees learn without sucrose reward that a color cue signals an open entrance. In this experiment, bees with high sucrose acceptance thresholds showed significantly better learning and reversal learning than bees with low thresholds. These results demonstrate that sucrose acceptance thresholds affect only those forms of learning in which sucrose serves as the reward. The results also show that foraging behavior in the field is a good predictor for learning behavior in the field and in the laboratory.

Graphing techniques for materials laboratory using Excel

NASA Technical Reports Server (NTRS)

Kundu, Nikhil K.

1994-01-01

Engineering technology curricula stress hands on training and laboratory practices in most of the technical courses. Laboratory reports should include analytical as well as graphical evaluation of experimental data. Experience shows that many students neither have the mathematical background nor the expertise for graphing. This paper briefly describes the procedure and data obtained from a number of experiments such as spring rate, stress concentration, endurance limit, and column buckling for a variety of materials. Then with a brief introduction to Microsoft Excel the author explains the techniques used for linear regression and logarithmic graphing.

Simulated and Virtual Science Laboratory Experiments: Improving Critical Thinking and Higher-Order Learning Skills

NASA Astrophysics Data System (ADS)

Simon, Nicole A.

Virtual laboratory experiments using interactive computer simulations are not being employed as viable alternatives to laboratory science curriculum at extensive enough rates within higher education. Rote traditional lab experiments are currently the norm and are not addressing inquiry, Critical Thinking, and cognition throughout the laboratory experience, linking with educational technologies (Pyatt & Sims, 2007; 2011; Trundle & Bell, 2010). A causal-comparative quantitative study was conducted with 150 learners enrolled at a two-year community college, to determine the effects of simulation laboratory experiments on Higher-Order Learning, Critical Thinking Skills, and Cognitive Load. The treatment population used simulated experiments, while the non-treatment sections performed traditional expository experiments. A comparison was made using the Revised Two-Factor Study Process survey, Motivated Strategies for Learning Questionnaire, and the Scientific Attitude Inventory survey, using a Repeated Measures ANOVA test for treatment or non-treatment. A main effect of simulated laboratory experiments was found for both Higher-Order Learning, [F (1, 148) = 30.32,p = 0.00, eta2 = 0.12] and Critical Thinking Skills, [F (1, 148) = 14.64,p = 0.00, eta 2 = 0.17] such that simulations showed greater increases than traditional experiments. Post-lab treatment group self-reports indicated increased marginal means (+4.86) in Higher-Order Learning and Critical Thinking Skills, compared to the non-treatment group (+4.71). Simulations also improved the scientific skills and mastery of basic scientific subject matter. It is recommended that additional research recognize that learners' Critical Thinking Skills change due to different instructional methodologies that occur throughout a semester.

Raising environmental awareness through applied biochemistry laboratory experiments.

PubMed

Salman Ashraf, S

2013-01-01

Our environment is under constant pressure and threat from various sources of pollution. Science students, in particular chemistry students, must not only be made aware of these issues, but also be taught that chemistry (and science) can provide solutions to such real-life issues. To this end, a newly developed biochemistry laboratory experiment is described that guides students to learn about the applicability of peroxidase enzymes to degrade organic dyes (as model pollutants) in simulated waste water. In addition to showing how enzymes can potentially be used for waste water remediation, various factors than can affect enzyme-based reactions such as pH, temperature, concentration of substrates/enzymes, and denaturants can also be tested. This "applied biotechnology" experiment was successfully implemented in an undergraduate biochemistry laboratory course to enhance students' learning of environmental issues as well important biochemistry concepts. Student survey confirmed that this laboratory experiment was successful in achieving the objectives of raising environmental awareness in students and illustrating the usefulness of chemistry in solving real-life problems. This experiment can be easily adopted in an introductory biochemistry laboratory course and taught as an inquiry-guided exercise. © 2013 by The International Union of Biochemistry and Molecular Biology.

Mobilization of natural colloids from an iron oxide-coated sand aquifer--Effect of pH and ionic strength

USGS Publications Warehouse

Bunn, Rebecca A.; Magelky, Robin D.; Ryan, Joseph N.; Elimelech, Menachem

2002-01-01

Field and laboratory column experiments were performed to assess the effect of elevated pH and reduced ionic strength on the mobilization of natural colloids in a ferric oxyhydroxide-coated aquifer sediment. The field experiments were conducted as natural gradient injections of groundwater amended by sodium hydroxide additions. The laboratory experiments were conducted in columns of undisturbed, oriented sediments and disturbed, disoriented sediments. In the field, the breakthrough of released colloids coincided with the pH pulse breakthrough and lagged the bromide tracer breakthrough. The breakthrough behavior suggested that the progress of the elevated pH front controlled the transport of the mobilized colloids. In the laboratory, about twice as much colloid release occurred in the disturbed sediments as in the undisturbed sediments. The field and laboratory experiments both showed that the total mass of colloid release increased with increasing pH until the concurrent increase in ionic strength limited release. A decrease in ionic strength did not mobilize significant amounts of colloids in the field. The amount of colloids released normalized to the mass of the sediments was similar for the field and the undisturbed laboratory experiments.

Dynamics of animal movement in an ecological context: dragonfly wing damage reduces flight performance and predation success

PubMed Central

Combes, S. A.; Crall, J. D.; Mukherjee, S.

2010-01-01

Much of our understanding of the control and dynamics of animal movement derives from controlled laboratory experiments. While many aspects of animal movement can be probed only in these settings, a more complete understanding of animal locomotion may be gained by linking experiments on relatively simple motions in the laboratory to studies of more complex behaviours in natural settings. To demonstrate the utility of this approach, we examined the effects of wing damage on dragonfly flight performance in both a laboratory drop–escape response and the more natural context of aerial predation. The laboratory experiment shows that hindwing area loss reduces vertical acceleration and average flight velocity, and the predation experiment demonstrates that this type of wing damage results in a significant decline in capture success. Taken together, these results suggest that wing damage may take a serious toll on wild dragonflies, potentially reducing both reproductive success and survival. PMID:20236968

In situ impact of petrochemicals on the photosynthesis of the seagrass Zostera capricorni.

PubMed

Macinnis-Ng, Catriona M O; Ralph, Peter J

2003-11-01

We used photosynthetic activity (measured as chlorophyll a fluorescence) and photosynthetic pigment concentrations to assess the effect of pulsed exposures of aged crude oil (Champion Crude), dispersant (VDC) and an oil+dispersant mixture on the seagrass Zostera capricorni Aschers in laboratory and field experiments, using custom-made chambers. Samples were exposed for 10 h to 0.25% and 0.1% concentrations of aged crude oil and dispersant as well as mixtures of 0.25% oil+0.05% dispersant and 0.1% oil+0.02% dispersant. During this time and for the subsequent four day recovery period, the maximum and effective quantum yields of photosystem II (Fv/Fm and DeltaF/Fm' respectively) were measured. In the laboratory experiments, both values declined in response to oil exposure and remained low during the recovery period. Dispersant exposure caused a decline in both values during the recovery period, while the mixture of aged crude oil+dispersant had little impact on both quantum yields. In situ samples were less sensitive than laboratory samples, showing no photosynthetic impact due to dispersant and oil+dispersant mixture. Despite an initial decline in DeltaF/Fm', in situ oil-exposed samples recovered by the end of the experiment. Chlorophyll pigment analysis showed only limited ongoing impact in both laboratory and field situations. This study suggests that laboratory experiments may overestimate the ongoing impact of petrochemicals on seagrass whilst the dispersant VDC can reduce the impact of oil on seagrass photosynthesis.

Pyranometer offsets triggered by ambient meteorology: insights from laboratory and field experiments

NASA Astrophysics Data System (ADS)

Oswald, Sandro M.; Pietsch, Helga; Baumgartner, Dietmar J.; Weihs, Philipp; Rieder, Harald E.

2017-03-01

This study investigates the effects of ambient meteorology on the accuracy of radiation (R) measurements performed with pyranometers contained in various heating and ventilation systems (HV-systems). It focuses particularly on instrument offsets observed following precipitation events. To quantify pyranometer responses to precipitation, a series of controlled laboratory experiments as well as two targeted field campaigns were performed in 2016. The results indicate that precipitation (as simulated by spray tests or observed under ambient conditions) significantly affects the thermal environment of the instruments and thus their stability. Statistical analyses of laboratory experiments showed that precipitation triggers zero offsets of -4 W m-2 or more, independent of the HV-system. Similar offsets were observed in field experiments under ambient environmental conditions, indicating a clear exceedance of BSRN (Baseline Surface Radiation Network) targets following precipitation events. All pyranometers required substantial time to return to their initial signal states after the simulated precipitation events. Therefore, for BSRN-class measurements, the recommendation would be to flag the radiation measurements during a natural precipitation event and 90 min after it in nighttime conditions. Further daytime experiments show pyranometer offsets of 50 W m-2 or more in comparison to the reference system. As they show a substantially faster recovery, the recommendation would be to flag the radiation measurements within a natural precipitation event and 10 min after it in daytime conditions.

Cross-Linking Proteins To Show Complex Formation: A Laboratory That Visually Demonstrates Calmodulin Binding to Calmodulin Kinase II.

ERIC Educational Resources Information Center

Porta, Angela R.

2003-01-01

Presents a laboratory experiment demonstrating the binding of calcium/calmodulin to calmodulin kinase II, which is important in the metabolic and physiological activities of the cell. Uses SDS polyacrylamide gel electrophoresis (PAGE). (YDS)

Views of South African Chemistry Students in University Bridging Programs on the Reliability of Experimental Data

NASA Astrophysics Data System (ADS)

Rollnick, Marissa; Dlamini, Betty; Lotz, Sandra; Lubben, Fred

2001-08-01

This paper reports an investigation of the status of procedural knowledge in chemistry amongst students entering into bridging programs at two South African universities. The students answered a questionnaire which investigated their perceived reasons for repeating readings and their ideas about handling data. Students also answered a question on laboratory apparatus which was used to assess their laboratory experience. The overall responses were analysed, as well as their relationship to laboratory experience and home language. The findings show that students overall tend to repeat in order to get a recurring reading. Very few students were able to use a line of best fit for a set of graphical data. There is some relationship between their responses and previous laboratory experiences, but little fundamental difference between the responses of the two main language groups. Some implications for tertiary education in chemistry are discussed.

The effectiveness of using computer simulated experiments on junior high students' understanding of the volume displacement concept

NASA Astrophysics Data System (ADS)

Choi, Byung-Soon; Gennaro, Eugene

Several researchers have suggested that the computer holds much promise as a tool for science teachers for use in their classrooms (Bork, 1979, Lunetta & Hofstein, 1981). It also has been said that there needs to be more research in determining the effectiveness of computer software (Tinker, 1983).This study compared the effectiveness of microcomputer simulated experiences with that of parallel instruction involving hands-on laboratory experiences for teaching the concept of volume displacement to junior high school students. This study also assessed the differential effect on students' understanding of the volume displacement concept using sex of the students as another independent variable. In addition, it compared the degree of retention, after 45 days, of both treatment groups.It was found that computer simulated experiences were as effective as hands-on laboratory experiences, and that males, having had hands-on laboratory experiences, performed better on the posttest than females having had the hands-on laboratory experiences. There were no significant differences in performance when comparing males with females using the computer simulation in the learning of the displacement concept. This study also showed that there were no significant differences in the retention levels when the retention scores of the computer simulation groups were compared to those that had the hands-on laboratory experiences. However, an ANOVA of the retention test scores revealed that males in both treatment conditions retained knowledge of volume displacement better than females.

Can One Lab Make a Difference?

ERIC Educational Resources Information Center

Abbott, David S.; Saul, Jeffery M.; Parker, George W.; Beichner, Robert J.

2000-01-01

Investigates whether replacing a single traditional laboratory activity with a widely-used, non-microcomputer-based laboratory, research-based activity could produce improved conceptual understanding of a topic in electricity. Shows that a single instructional experience utilizing the research-based tutorial materials is superior to a traditional…

Cosmic Ray Studies on Skies and on Campus.

ERIC Educational Resources Information Center

Jones, Brian

1993-01-01

Outlines the highlights of experiments that allow students to trace the historical development of our understandings of cosmic rays. The experiments provide for two outdoor fieldwork experiences, indoor laboratory work, and an opportunity for a group of students to show originality and initiative. (ZWH)

Development of a Portable Motor Learning Laboratory (PoMLab)

PubMed Central

Shinya, Masahiro

2016-01-01

Most motor learning experiments have been conducted in a laboratory setting. In this type of setting, a huge and expensive manipulandum is frequently used, requiring a large budget and wide open space. Subjects also need to travel to the laboratory, which is a burden for them. This burden is particularly severe for patients with neurological disorders. Here, we describe the development of a novel application based on Unity3D and smart devices, e.g., smartphones or tablet devices, that can be used to conduct motor learning experiments at any time and in any place, without requiring a large budget and wide open space and without the burden of travel on subjects. We refer to our application as POrtable Motor learning LABoratory, or PoMLab. PoMLab is a multiplatform application that is available and sharable for free. We investigated whether PoMLab could be an alternative to the laboratory setting using a visuomotor rotation paradigm that causes sensory prediction error, enabling the investigation of how subjects minimize the error. In the first experiment, subjects could adapt to a constant visuomotor rotation that was abruptly applied at a specific trial. The learning curve for the first experiment could be modeled well using a state space model, a mathematical model that describes the motor leaning process. In the second experiment, subjects could adapt to a visuomotor rotation that gradually increased each trial. The subjects adapted to the gradually increasing visuomotor rotation without being aware of the visuomotor rotation. These experimental results have been reported for conventional experiments conducted in a laboratory setting, and our PoMLab application could reproduce these results. PoMLab can thus be considered an alternative to the laboratory setting. We also conducted follow-up experiments in university physical education classes. A state space model that was fit to the data obtained in the laboratory experiments could predict the learning curves obtained in the follow-up experiments. Further, we investigated the influence of vibration function, weight, and screen size on learning curves. Finally, we compared the learning curves obtained in the PoMLab experiments to those obtained in the conventional reaching experiments. The results of the in-class experiments show that PoMLab can be used to conduct motor learning experiments at any time and place. PMID:27348223

Development of a Portable Motor Learning Laboratory (PoMLab).

PubMed

Takiyama, Ken; Shinya, Masahiro

2016-01-01

Most motor learning experiments have been conducted in a laboratory setting. In this type of setting, a huge and expensive manipulandum is frequently used, requiring a large budget and wide open space. Subjects also need to travel to the laboratory, which is a burden for them. This burden is particularly severe for patients with neurological disorders. Here, we describe the development of a novel application based on Unity3D and smart devices, e.g., smartphones or tablet devices, that can be used to conduct motor learning experiments at any time and in any place, without requiring a large budget and wide open space and without the burden of travel on subjects. We refer to our application as POrtable Motor learning LABoratory, or PoMLab. PoMLab is a multiplatform application that is available and sharable for free. We investigated whether PoMLab could be an alternative to the laboratory setting using a visuomotor rotation paradigm that causes sensory prediction error, enabling the investigation of how subjects minimize the error. In the first experiment, subjects could adapt to a constant visuomotor rotation that was abruptly applied at a specific trial. The learning curve for the first experiment could be modeled well using a state space model, a mathematical model that describes the motor leaning process. In the second experiment, subjects could adapt to a visuomotor rotation that gradually increased each trial. The subjects adapted to the gradually increasing visuomotor rotation without being aware of the visuomotor rotation. These experimental results have been reported for conventional experiments conducted in a laboratory setting, and our PoMLab application could reproduce these results. PoMLab can thus be considered an alternative to the laboratory setting. We also conducted follow-up experiments in university physical education classes. A state space model that was fit to the data obtained in the laboratory experiments could predict the learning curves obtained in the follow-up experiments. Further, we investigated the influence of vibration function, weight, and screen size on learning curves. Finally, we compared the learning curves obtained in the PoMLab experiments to those obtained in the conventional reaching experiments. The results of the in-class experiments show that PoMLab can be used to conduct motor learning experiments at any time and place.

Laboratory based instruction in Pakistan: Comparative evaluation of three laboratory instruction methods in biological science at higher secondary school level

NASA Astrophysics Data System (ADS)

Cheema, Tabinda Shahid

This study of laboratory based instruction at higher secondary school level was an attempt to gain some insight into the effectiveness of three laboratory instruction methods: cooperative group instruction method, individualised instruction method and lecture demonstration method on biology achievement and retention. A Randomised subjects, Pre-test Post-test Comparative Methods Design was applied. Three groups of students from a year 11 class in Pakistan conducted experiments using the different laboratory instruction methods. Pre-tests, achievement tests after the experiments and retention tests one month later were administered. Results showed no significant difference between the groups on total achievement and retention, nor was there any significant difference on knowledge and comprehension test scores or skills performance. Future research investigating a similar problem is suggested.

Definition of experiments and instruments for a communication/navigation research laboratory. Volume 4: Programmatics

NASA Technical Reports Server (NTRS)

1972-01-01

Details are provided for scheduling, cost estimates, and support research and technology requirements for a space shuttle supported manned research laboratory to conduct selected communication and navigation experiments. A summary of the candidate program and its time phasing is included, as well as photographs of the 1/20 scale model of the shuttle supported Early Comm/Nav Research Lab showing the baseline, in-bay arrangement and the out-of-bay configuration.

KSC-00PADIG-020

NASA Image and Video Library

2002-05-02

This diagram shows the planned locations of the Space Experiment Research and Processing Laboratory (SERPL) and the Space Station Commerce Park at Kennedy Space Center. The SERPL is a planned 100,000-square-foot laboratory that will provide expanded and upgraded facilities for hosting International Space Station experiment processing. In addition, it will provide better support for other biological and life sciences payload processing at KSC. It will serve as a magnet facility for the planned 400-acre Commerce Park.

Flow dynamics and salt transport in a coastal aquifer driven by a stratified saltwater body: Lab experiment and numerical modeling

NASA Astrophysics Data System (ADS)

Oz, Imri; Shalev, Eyal; Yechieli, Yoseph; Gavrieli, Ittai; Gvirtzman, Haim

2014-04-01

This paper examines the transient development and the steady-state configuration of groundwater within a coastal aquifer adjacent to a stratified saltwater body. Such systems consist of three different water types: the regional fresh groundwater, and low and high salinity brines forming the upper and lower water layers of the stratified water body, respectively. The dynamics, location and the geometry of the interfaces and the density-driven circulation flows that develop in the aquifer are examined using laboratory experiments and numerical modeling at the same scale. The results show that the transient intrusion of the different water bodies into the aquifer takes place at different rates, and that the locations of the interfaces between them change with time, before reaching steady-state. Under steady-state conditions both the model and the experiments show the existence of three interfaces between the three water types. The numerical model, which is calibrated against the salinity distribution and groundwater discharge rate in the laboratory experiments, allows the quantification of the flow rates and flow patterns within the aquifer. These flow patterns, which cannot be derived from laboratory experiments, show the transient development of three circulation cells which are confined between the three interfaces. These results confirm the hypothesis that has been previously suggested based solely on a steady-state numerical modeling defined by a conceptual understanding. Parametric analysis shows that the creation of three circulation cells and three interfaces is limited to certain conditions and defines the ranges for the creation of this unique system.

Raoult's Law: A General Chemistry Experiment.

ERIC Educational Resources Information Center

Steffel, Margaret J.

1983-01-01

To make material on Raoult's law more meaningful, students complete exercises on paper, in the laboratory, and with molecular models. Paper exercises give practice using the law; laboratory work illustrates behavior of real solutions; and models show relationships between properties of individual molecules and of matter in bulk. (JN)

Accreditation experience of radioisotope metrology laboratory of Argentina.

PubMed

Iglicki, A; Milá, M I; Furnari, J C; Arenillas, P; Cerutti, G; Carballido, M; Guillén, V; Araya, X; Bianchini, R

2006-01-01

This work presents the experience developed by the Radioisotope Metrology Laboratory (LMR), of the Argentine National Atomic Energy Commission (CNEA), as result of the accreditation process of the Quality System by ISO 17025 Standard. Considering the LMR as a calibration laboratory, services of secondary activity determinations and calibration of activimeters used in Nuclear Medicine were accredited. A peer review of the (alpha/beta)-gamma coincidence system was also carried out. This work shows in detail the structure of the quality system, the results of the accrediting audit and gives the number of non-conformities detected and of observations made which have all been resolved.

Integrating teaching and authentic research in the field and laboratory settings

NASA Astrophysics Data System (ADS)

Daryanto, S.; Wang, L.; Kaseke, K. F.; Ravi, S.

2016-12-01

Typically authentic research activities are separated from rigorous classroom teaching. Here we assessed the potential of integrating teaching and research activities both in the field and in the laboratory. We worked with students from both US and abroad without strong science background to utilize advanced environmental sensors and statistical tool to conduct innovative projects. The students include one from Namibia and two local high school students in Indianapolis (through Project SEED, Summer Experience for the Economically Disadvantaged). They conducted leaf potential measurements, isotope measurements and meta-analysis. The experience showed us the great potential of integrating teaching and research in both field and laboratory settings.

Laboratory evaluation of predation on mosquito larvae by Australian mangrove fish.

PubMed

Griffin, Lachlan

2014-06-01

A series of laboratory experiments compared predation rates of three native eastern Australian mangrove fish species (Psuedomugil signifer, Hyseleotris galii, Pseudogobius sp.) and the exotic Gambusia holbrooki on 2nd and 4th instar Aedes vigilax larvae, in order to determine their potential as mosquito control agents in mangrove forests. All four species preyed on significant numbers of both 2nd and 4th instar larvae. All showed a similar pattern of larval consumption, gorging on larvae in the first hour of each experiment, before reducing to a relatively constant background feeding rate. Gambusia holbrooki showed the highest larval consumption rates, but is unsuitable as a mosquito control agent due to it being an exotic pest species in Australia. Of the three native species, P. signifer showed the greatest potential as a mosquito control agent, having consumption rates comparable to G. holbrooki, and was the only species that did not show a significant reduction in larval consumption in the night experiments. © 2014 The Society for Vector Ecology.

Low-cost nonlinear optics experiment for undergraduate instructional laboratory and lecture demonstration

NASA Astrophysics Data System (ADS)

Turchiello, Rozane de F.; Pereira, Luiz A. A.; Gómez, Sergio L.

2017-07-01

This paper presents a simple and affordable experiment on the thermal lens effect, suitable for an undergraduate educational laboratory or as a tabletop demonstration in a lecture on nonlinear optics. Such an experiment exploits the formation of a lens in an absorbing medium illuminated by a laser beam with a Gaussian intensity profile. As an absorber, we use a commercial soy sauce, which exhibits a strong thermal lensing effect. Additionally, we show how to measure the radius of a Gaussian beam using the knife-edge method, and how to estimate the focal length of the induced thermal lens.

On cosmology in the laboratory

PubMed Central

Leonhardt, Ulf

2015-01-01

In transformation optics, ideas from general relativity have been put to practical use for engineering problems. This article asks the question how this debt can be repaid. In discussing a series of recent laboratory experiments, it shows how insights from wave phenomena shed light on the quantum physics of the event horizon. PMID:26217062

On cosmology in the laboratory.

PubMed

Leonhardt, Ulf

2015-08-28

In transformation optics, ideas from general relativity have been put to practical use for engineering problems. This article asks the question how this debt can be repaid. In discussing a series of recent laboratory experiments, it shows how insights from wave phenomena shed light on the quantum physics of the event horizon.

Biofilm resilience to desiccation in groundwater aquifers: a laboratory and field study.

PubMed

Weaver, L; Webber, J B; Hickson, A C; Abraham, P M; Close, M E

2015-05-01

Groundwater is used as a precious resource for drinking water worldwide. Increasing anthropogenic activity is putting increasing pressure on groundwater resources. One impact of increased groundwater abstraction coupled with increasing dry weather events is the lowering of groundwater levels within aquifers. Biofilms within groundwater aquifers offer protection to the groundwater by removing contaminants entering the aquifer systems from land use activities. The study presented investigated the impact of desiccation events on the biofilms present in groundwater aquifers using field and laboratory experiments. In both field and laboratory experiments a reduction in enzyme activity (glucosidase, esterase and phosphatase) was seen during desiccation compared to wet controls. However, comparing all the data together no significant differences were seen between either wet or desiccated samples or between the start and end of the experiments. In both field and laboratory experiments enzyme activity recovered to start levels after return to wet conditions. The study shows that biofilms within groundwater systems are resilient and can withstand periods of desiccation (4 months). Copyright © 2014 Elsevier B.V. All rights reserved.

In-Situ Tuff Water Migration/Heater Experiment: posttest thermal analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eaton, R.R.; Johnstone, J.K.; Nunziato, J.W.

This report describes posttest laboratory experiments and thermal computations for the In-Situ Tuff Water Migration/Heater Experiment that was conducted in Grouse Canyon Welded Tuff in G-Tunnel, Nevada Test Site. Posttest laboratory experiments were designed to determine the accuracy of the temperatures measured by the rockwall thermocouples during the in-situ test. The posttest laboratory experiments showed that the measured in-situ rockwall temperatures were 10 to 20{sup 0}C higher than the true rockwall temperatures. The posttest computational results, obtained with the thermal conduction code COYOTE, were compared with the experimentally obtained data and with calculated pretest results. Daily heater output power fluctuationsmore » (+-4%) caused by input power line variations and the sensitivity of temperature to heater output power required care in selecting the average heater output power values used in the code. The posttest calculated results compare reasonably well with the experimental data. 10 references, 14 figures, 5 tables.« less

The testing effect for mediator final test cues and related final test cues in online and laboratory experiments.

PubMed

Coppens, Leonora C; Verkoeijen, Peter P J L; Bouwmeester, Samantha; Rikers, Remy M J P

2016-05-31

The testing effect is the finding that information that is retrieved during learning is more often correctly retrieved on a final test than information that is restudied. According to the semantic mediator hypothesis the testing effect arises because retrieval practice of cue-target pairs (mother-child) activates semantically related mediators (father) more than restudying. Hence, the mediator-target (father-child) association should be stronger for retrieved than restudied pairs. Indeed, Carpenter (2011) found a larger testing effect when participants received mediators (father) than when they received target-related words (birth) as final test cues. The present study started as an attempt to test an alternative account of Carpenter's results. However, it turned into a series of conceptual (Experiment 1) and direct (Experiment 2 and 3) replications conducted with online samples. The results of these online replications were compared with those of similar existing laboratory experiments through small-scale meta-analyses. The results showed that (1) the magnitude of the raw mediator testing effect advantage is comparable for online and laboratory experiments, (2) in both online and laboratory experiments the magnitude of the raw mediator testing effect advantage is smaller than in Carpenter's original experiment, and (3) the testing effect for related cues varies considerably between online experiments. The variability in the testing effect for related cues in online experiments could point toward moderators of the related cue short-term testing effect. The raw mediator testing effect advantage is smaller than in Carpenter's original experiment.

Detritus utilization by Mytilus edulis

NASA Astrophysics Data System (ADS)

Williams, Phil

1981-06-01

Feeding expriments showed that salt marsh vascular plant detritus is a poor food for Mytilus edulis. In laboratory experiment tissue weight of mussels increased slightly when Spartina foliosa and Salicornia virginica detritus was added to background seawater rich in organic matter. However, mussels lost weight when detritus was added to background seawater with a lower organic matter content. Aged and unaged plant material were equally poor in food value for M. edulis. Mussels in the Tijuana Estuary grew substantially during the period of the laboratory experiments.

Analytical and Experimental Verification of a Flight Article for a Mach-8 Boundary-Layer Experiment

NASA Technical Reports Server (NTRS)

Richards, W. Lance; Monaghan, Richard C.

1996-01-01

Preparations for a boundary-layer transition experiment to be conducted on a future flight mission of the air-launched Pegasus(TM) rocket are underway. The experiment requires a flight-test article called a glove to be attached to the wing of the Mach-8 first-stage booster. A three-dimensional, nonlinear finite-element analysis has been performed and significant small-scale laboratory testing has been accomplished to ensure the glove design integrity and quality of the experiment. Reliance on both the analysis and experiment activities has been instrumental in the success of the flight-article design. Results obtained from the structural analysis and laboratory testing show that all glove components are well within the allowable thermal stress and deformation requirements to satisfy the experiment objectives.

Experience of quality management system in a clinical laboratory in Nigeria

PubMed Central

Sylvester-Ikondu, Ugochukwu; Onwuamah, Chika K.; Salu, Olumuyiwa B.; Ige, Fehintola A.; Meshack, Emily; Aniedobe, Maureen; Amoo, Olufemi S.; Okwuraiwe, Azuka P.; Okhiku, Florence; Okoli, Chika L.; Fasela, Emmanuel O.; Odewale, Ebenezer. O.; Aleshinloye, Roseline O.; Olatunji, Micheal; Idigbe, Emmanuel O.

2012-01-01

Issues Quality-management systems (QMS) are uncommon in clinical laboratories in Nigeria, and until recently, none of the nation’s 5 349 clinical laboratories have been able to attain the certifications necessary to begin the process of attaining international accreditation. Nigeria’s Human Virology Laboratory (HVL), however, began implementation of a QMS in 2006, and in 2008 it was determined that the laboratory conformed to the requirements of ISO 9001:2000 (now 2008), making it the first diagnostic laboratory to be certified in Nigeria. The HVL has now applied for the World Health Organization (WHO) accreditation preparedness scheme. The experience of the QMS implementation process and the lessons learned therein are shared here. Description In 2005, two personnel from the HVL spent time studying quality systems in a certified clinical laboratory in Dakar, Senegal. Following this peer-to-peer technical assistance, several training sessions were undertaken by HVL staff, a baseline assessment was conducted, and processes were established. The HVL has monitored its quality indicators and conducted internal and external audits; these analyses (from 2007 to 2009) are presented herein. Lessons learned Although there was improvement in the pre-analytical and analytical indicators analysed and although data-entry errors decreased in the post-analytical process, the delay in returning laboratory test results increased significantly. There were several factors identified as causes for this delay and all of these have now been addressed except for an identified need for automation of some high-volume assays (currently being negotiated). Internal and external audits showed a trend of increasing non-conformities which could be the result of personnel simply becoming lax over time. Application for laboratory accreditation, however, could provide the renewed vigour needed to correct these non-conformities. Recommendation This experience shows that sustainability of the QMS at present is a cause for concern. However, the tiered system of accreditation being developed by WHO–Afro may act as a driving force to preserve the spirit of continual improvement. PMID:29062734

A 50-year research journey. From laboratory to clinic.

PubMed

Ross, John

2009-01-01

Prior important research is not always cited, exemplified by Oswald Avery's pioneering discovery that DNA is the genetic transforming factor; it was not cited by Watson and Crick 10 years later. My first laboratory research (National Institutes of Health 1950s) resulted in the clinical development of transseptal left heart catheterization. Laboratory studies on cardiac muscle mechanics in normal and failing hearts led to the concept of afterload mismatch with limited preload reserve. At the University of California, San Diego in La Jolla (1968) laboratory experiments on coronary artery reperfusion after sustained coronary occlusion showed salvage of myocardial tissue, a potential treatment for acute myocardial infarction proven in clinical trials of thrombolysis 14 years later. Among 60 trainees who worked with me in La Jolla, one-third were Japanese and some of their important laboratory experiments are briefly recounted, beginning with Sasayama, Tomoike and Shirato in the 1970 s. Recently, we developed a method for cardiac gene transfer, and subsequently we showed that gene therapy for the defect in cardiomyopathic hamsters halted the progression of advanced disease. Cardiovascular research and medicine are producing continuing advances in technologies for gene transfer and embryonic stem cell transplantation, targeting of small molecules, and tissue and organ engineering.

Decision support for clinical laboratory capacity planning.

PubMed

van Merode, G G; Hasman, A; Derks, J; Goldschmidt, H M; Schoenmaker, B; Oosten, M

1995-01-01

The design of a decision support system for capacity planning in clinical laboratories is discussed. The DSS supports decisions concerning the following questions: how should the laboratory be divided into job shops (departments/sections), how should staff be assigned to workstations and how should samples be assigned to workstations for testing. The decision support system contains modules for supporting decisions at the overall laboratory level (concerning the division of the laboratory into job shops) and for supporting decisions at the job shop level (assignment of staff to workstations and sample scheduling). Experiments with these modules are described showing both the functionality and the validity.

Comparison between Linear and Nonlinear Regression in a Laboratory Heat Transfer Experiment

ERIC Educational Resources Information Center

Gonçalves, Carine Messias; Schwaab, Marcio; Pinto, José Carlos

2013-01-01

In order to interpret laboratory experimental data, undergraduate students are used to perform linear regression through linearized versions of nonlinear models. However, the use of linearized models can lead to statistically biased parameter estimates. Even so, it is not an easy task to introduce nonlinear regression and show for the students…

An overview of Quality Management System implementation in a research laboratory

NASA Astrophysics Data System (ADS)

Molinéro-Demilly, Valérie; Charki, Abdérafi; Jeoffrion, Christine; Lyonnet, Barbara; O'Brien, Steve; Martin, Luc

2018-02-01

The aim of this paper is to show the advantages of implementing a Quality Management System (QMS) in a research laboratory in order to improve the management of risks specific to research programmes and to increase the reliability of results. This paper also presents experience gained from feedback following the implementation of the Quality process in a research laboratory at INRA, the French National Institute for Agronomic Research and details the various challenges encountered and solutions proposed to help achieve smoother adoption of a QMS process. The 7Ms (Management, Measurement, Manpower, Methods, Materials, Machinery, Mother-nature) methodology based on the Ishikawa `Fishbone' diagram is used to show the effectiveness of the actions considered by a QMS, which involve both the organization and the activities of the laboratory. Practical examples illustrate the benefits and improvements observed in the laboratory.

Accretion shocks in the laboratory: Design of an experiment to study star formation

DOE PAGES

Young, Rachel P.; Kuranz, C. C.; Drake, R. P.; ...

2017-02-13

Here, we present the design of a laboratory-astrophysics experiment to study magnetospheric accretion relevant to young, pre-main-sequence stars. Spectra of young stars show evidence of hotspots created when streams of accreting material impact the surface of the star and create shocks. The structures that form during this process are poorly understood, as the surfaces of young stars cannot be spatially resolved. Our experiment would create a scaled "accretion shock" at a major (several kJ) laser facility. The experiment drives a plasma jet (the "accretion stream") into a solid block (the "stellar surface"), in the presence of a parallel magnetic fieldmore » analogous to the star's local field.« less

A new approach to electrophoresis in space

NASA Technical Reports Server (NTRS)

Snyder, Robert S.; Rhodes, Percy H.

1990-01-01

Previous electrophoresis experiments performed in space are reviewed. There is sufficient data available from the results of these experiments to show that they were designed with incomplete knowledge of the fluid dynamics of the process including electrohydrodynamics. Redesigning laboratory chambers and operating procedures developed on Earth for space without understanding both the advantages and disadvantages of the microgravity environment has yielded poor separations of both cells and proteins. However, electrophoreris is still an important separation tool in the laboratory and thermal convection does limit its performance. Thus, there is a justification for electrophoresis but the emphasis of future space experiments must be directed toward basic research with model experiments to understand the microgravity environment and fluid analysis to test the basic principles of the process.

Measuring ignitability for in situ burning of oil spills weathered under Arctic conditions: from laboratory studies to large-scale field experiments.

PubMed

Fritt-Rasmussen, Janne; Brandvik, Per Johan

2011-08-01

This paper compares the ignitability of Troll B crude oil weathered under simulated Arctic conditions (0%, 50% and 90% ice cover). The experiments were performed in different scales at SINTEF's laboratories in Trondheim, field research station on Svalbard and in broken ice (70-90% ice cover) in the Barents Sea. Samples from the weathering experiments were tested for ignitability using the same laboratory burning cell. The measured ignitability from the experiments in these different scales showed a good agreement for samples with similar weathering. The ice conditions clearly affected the weathering process, and 70% ice or more reduces the weathering and allows a longer time window for in situ burning. The results from the Barents Sea revealed that weathering and ignitability can vary within an oil slick. This field use of the burning cell demonstrated that it can be used as an operational tool to monitor the ignitability of oil spills. Copyright © 2011 Elsevier Ltd. All rights reserved.

Solute and heat transport model of the Henry and Hilleke laboratory experiment

USGS Publications Warehouse

Langevin, C.D.; Dausman, A.M.; Sukop, M.C.

2010-01-01

SEAWAT is a coupled version of MODFLOW and MT3DMS designed to simulate variable-density ground water flow and solute transport. The most recent version of SEAWAT, called SEAWAT Version 4, includes new capabilities to represent simultaneous multispecies solute and heat transport. To test the new features in SEAWAT, the laboratory experiment of Henry and Hilleke (1972) was simulated. Henry and Hilleke used warm fresh water to recharge a large sand-filled glass tank. A cold salt water boundary was represented on one side. Adjustable heating pads were used to heat the bottom and left sides of the tank. In the laboratory experiment, Henry and Hilleke observed both salt water and fresh water flow systems separated by a narrow transition zone. After minor tuning of several input parameters with a parameter estimation program, results from the SEAWAT simulation show good agreement with the experiment. SEAWAT results suggest that heat loss to the room was more than expected by Henry and Hilleke, and that multiple thermal convection cells are the likely cause of the widened transition zone near the hot end of the tank. Other computer programs with similar capabilities may benefit from benchmark testing with the Henry and Hilleke laboratory experiment. Journal Compilation ?? 2009 National Ground Water Association.

How Should Students Learn in the School Science Laboratory? The Benefits of Cooperative Learning

NASA Astrophysics Data System (ADS)

Raviv, Ayala; Cohen, Sarit; Aflalo, Ester

2017-07-01

Despite the inherent potential of cooperative learning, there has been very little research into its effectiveness in middle school laboratory classes. This study focuses on an empirical comparison between cooperative learning and individual learning in the school science laboratory, evaluating the quality of learning and the students' attitudes. The research included 67 seventh-grade students who undertook four laboratory experiments on the subject of "volume measuring skills." Each student engaged both in individual and cooperative learning in the laboratory, and the students wrote individual or group reports, accordingly. A total of 133 experiment reports were evaluated, 108 of which also underwent textual analysis. The findings show that the group reports were superior, both in terms of understanding the concept of "volume" and in terms of acquiring skills for measuring volume. The students' attitudes results were statistically significant and demonstrated that they preferred cooperative learning in the laboratory. These findings demonstrate that science teachers should be encouraged to implement cooperative learning in the laboratory. This will enable them to improve the quality and efficiency of laboratory learning while using a smaller number of experimental kits. Saving these expenditures, together with the possibility to teach a larger number of students simultaneously in the laboratory, will enable greater exposure to learning in the school science laboratory.

Numerical modeling of dune progression in a high amplitude meandering channel

USDA-ARS?s Scientific Manuscript database

Laboratory experiments carried out by Abad and Garcia (2009) in a high-amplitude Kinoshita meandering channel show bed morphodynamics to comprise steady (local scour and deposition) and unsteady (migrating bedforms) components. The experiments are replicated with a numerical model. The sediment tran...

Sherlock Holmes and the Case of the Raven and the Ambassador's Wife: An Inquiry-Based Murder Mystery

ERIC Educational Resources Information Center

Grove, Nathaniel; Bretz, Stacey Lowery

2005-01-01

An inquiry-based experiment on Sherlock Holmes adventure stories used to actively involve students in a series of laboratory experiments to prove the guilt of the accused murderer is presented. The result from such experiments showed that students were able to distinguish between sugar and possible poison.

Near-infrared spectroscopy (NIRS) as a new tool for neuroeconomic research

PubMed Central

Kopton, Isabella M.; Kenning, Peter

2014-01-01

Over the last decade, the application of neuroscience to economic research has gained in importance and the number of neuroeconomic studies has grown extensively. The most common method for these investigations is fMRI. However, fMRI has limitations (particularly concerning situational factors) that should be countered with other methods. This review elaborates on the use of functional Near-Infrared Spectroscopy (fNIRS) as a new and promising tool for investigating economic decision making both in field experiments and outside the laboratory. We describe results of studies investigating the reliability of prototype NIRS studies, as well as detailing experiments using conventional and stationary fNIRS devices to analyze this potential. This review article shows that further research using mobile fNIRS for studies on economic decision making outside the laboratory could be a fruitful avenue helping to develop the potential of a new method for field experiments outside the laboratory. PMID:25147517

Using Visible Spectrophotometers and pH Measurements to Study Speciation in a Guided-Inquiry Laboratory

ERIC Educational Resources Information Center

Otto, William H.; Larive, Cynthia K.; Mason, Susan L.; Robinson, Janet B.; Heppert Joseph A.; Ellis, James D.

2005-01-01

An experiment to perform a simple initial investigation that illustrates concepts of speciation and equilibrium, using the instrument and chemical resources in the laboratory is presented. The investigation showed that the presence of multiple chemical species in a reaction mixture (phenol red solution) reflects the acid and base conditions…

A Study of High School Students' Performance of a Chemistry Experiment within the Virtual World of Second Life

ERIC Educational Resources Information Center

Winkelmann, Kurt; Scott, Matthew; Wong, Deborah

2014-01-01

A small group of high school students performed a virtual laboratory experiment in Second Life that mimicked a real experiment in both its appearance and procedure. Lab report grades were equivalent to report grades for hands-on experiments, and the quality of students' results was similar. Results of an attitudinal survey show that students…

Nutrient fluxes across sediment-water interface in Bohai Bay Coastal Zone, China.

PubMed

Mu, Di; Yuan, Dekui; Feng, Huan; Xing, Fangwei; Teo, Fang Yenn; Li, Shuangzhao

2017-01-30

Sediment cores and overlying water samples were collected at four sites in Tianjin Coastal Zone, Bohai Bay, to investigate nutrient (N, P and Si) exchanges across the sediment-water interface. The exchange fluxes of each nutrient species were estimated based on the porewater profiles and laboratory incubation experiments. The results showed significant differences between the two methods, which implied that molecular diffusion alone was not the dominant process controlling nutrient exchanges at these sites. The impacts of redox conditions and bioturbation on the nutrient fluxes were confirmed by the laboratory incubation experiments. The results from this study showed that the nutrient fluxes measured directly from the incubation experiment were more reliable than that predicted from the porewater profiles. The possible impacts causing variations in the nutrient fluxes include sewage discharge and land reclamation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Scaling effects in direct shear tests

USGS Publications Warehouse

Orlando, A.D.; Hanes, D.M.; Shen, H.H.

2009-01-01

Laboratory experiments of the direct shear test were performed on spherical particles of different materials and diameters. Results of the bulk friction vs. non-dimensional shear displacement are presented as a function of the non-dimensional particle diameter. Simulations of the direct shear test were performed using the Discrete Element Method (DEM). The simulation results show Considerable differences with the physical experiments. Particle level material properties, such as the coefficients of static friction, restitution and rolling friction need to be known a priori in order to guarantee that the simulation results are an accurate representation of the physical phenomenon. Furthermore, laboratory results show a clear size dependency on the results, with smaller particles having a higher bulk friction than larger ones. ?? 2009 American Institute of Physics.

[The experimental surgery and your relation with the university: an experience report].

PubMed

Yamaki, Vitor Nagai; Teixeira, Renan Kleber Costa; Feijo, Daniel Haber; Silva, José Antonio Cordero da; Botelho, Nara Macedo; Henriques, Marcus Vinicius

2014-01-01

The laboratory of experimental surgery represents one of the key points for the university, especially in the biomedical area. This focuses on the university's tripod of primary structure that are teaching, research and extension, which are essential for formation of humanistic and practice of a good doctor that is based, first of all, on scientific evidence and critical knowledge. The importance of a laboratory of experimental surgery centers for medical education was regulated from the new curriculum guidelines of the Ministério da Educação e Cultura, establishing a mandatory laboratory within college centers. Therefore, it is of great importance to the contribution of the laboratories of experimental surgery in the curriculum, both in the discipline of surgical technics and experimental surgery, and an incentive for basic research. Thus, the study presents the experience of 15 years of the Laboratory of Experimental Surgery from Universidade do Estado do Pará, with the goal show the importance of this to medical graduation and the university.

Laboratory constraints on models of earthquake recurrence

NASA Astrophysics Data System (ADS)

Beeler, N. M.; Tullis, Terry; Junger, Jenni; Kilgore, Brian; Goldsby, David

2014-12-01

In this study, rock friction "stick-slip" experiments are used to develop constraints on models of earthquake recurrence. Constant rate loading of bare rock surfaces in high-quality experiments produces stick-slip recurrence that is periodic at least to second order. When the loading rate is varied, recurrence is approximately inversely proportional to loading rate. These laboratory events initiate due to a slip-rate-dependent process that also determines the size of the stress drop and, as a consequence, stress drop varies weakly but systematically with loading rate. This is especially evident in experiments where the loading rate is changed by orders of magnitude, as is thought to be the loading condition of naturally occurring, small repeating earthquakes driven by afterslip, or low-frequency earthquakes loaded by episodic slip. The experimentally observed stress drops are well described by a logarithmic dependence on recurrence interval that can be cast as a nonlinear slip predictable model. The fault's rate dependence of strength is the key physical parameter. Additionally, even at constant loading rate the most reproducible laboratory recurrence is not exactly periodic, unlike existing friction recurrence models. We present example laboratory catalogs that document the variance and show that in large catalogs, even at constant loading rate, stress drop and recurrence covary systematically. The origin of this covariance is largely consistent with variability of the dependence of fault strength on slip rate. Laboratory catalogs show aspects of both slip and time predictability, and successive stress drops are strongly correlated indicating a "memory" of prior slip history that extends over at least one recurrence cycle.

Size-dependent reactivity of magnetite nanoparticles: a field-laboratory comparison

USGS Publications Warehouse

Swindle, Andrew L.; Elwood Madden, Andrew S.; Cozzarelli, Isabelle M.; Benamara, Mourad

2014-01-01

Logistic challenges make direct comparisons between laboratory- and field-based investigations into the size-dependent reactivity of nanomaterials difficult. This investigation sought to compare the size-dependent reactivity of nanoparticles in a field setting to a laboratory analog using the specific example of magnetite dissolution. Synthetic magnetite nanoparticles of three size intervals, ∼6 nm, ∼44 nm, and ∼90 nm were emplaced in the subsurface of the USGS research site at the Norman Landfill for up to 30 days using custom-made subsurface nanoparticle holders. Laboratory analog dissolution experiments were conducted using synthetic groundwater. Reaction products were analyzed via TEM and SEM and compared to initial particle characterizations. Field results indicated that an organic coating developed on the particle surfaces largely inhibiting reactivity. Limited dissolution occurred, with the amount of dissolution decreasing as particle size decreased. Conversely, the laboratory analogs without organics revealed greater dissolution of the smaller particles. These results showed that the presence of dissolved organics led to a nearly complete reversal in the size-dependent reactivity trends displayed between the field and laboratory experiments indicating that size-dependent trends observed in laboratory investigations may not be relevant in organic-rich natural systems.

Showing Its Colors. Thin-Layer Chromatographic Detection of Cannabinoid Metabolites.

ERIC Educational Resources Information Center

Bonicamp, Judith M.

1986-01-01

Describes a chemistry laboratory experiment in which thin-layer chromatography (TLC) is used to analyze urine specimens containing metabolites of the drug tetrahydro-cannabinol, which comes from the marijuana plant. The materials needed to conduct the experiment are listed, and the procedure and expected results are outlined. (TW)

Understanding Children's Science Identity through Classroom Interactions

ERIC Educational Resources Information Center

Kim, Mijung

2018-01-01

Research shows that various stereotypes about science and science learning, such as science being filled with hard and dry content, laboratory experiments, and male-dominated work environments, have resulted in feelings of distance from science in students' minds. This study explores children's experiences of science learning and science identity.…

Marketing Library and Information Services: Comparing Experiences at Large Institutions.

ERIC Educational Resources Information Center

Noel, Robert; Waugh, Timothy

This paper explores some of the similarities and differences between publicizing information services within the academic and corporate environments, comparing the marketing experiences of Abbot Laboratories (Illinois) and Indiana University. It shows some innovative online marketing tools, including an animated gif model of a large, integrated…

Educating Laboratory Science Learners at a Distance Using Interactive Television

ERIC Educational Resources Information Center

Reddy, Christopher

2014-01-01

Laboratory science classes offered to students learning at a distance require a methodology that allows for the completion of tactile activities. Literature describes three different methods of solving the distance laboratory dilemma: kit-based laboratory experience, computer-based laboratory experience, and campus-based laboratory experience,…

Flotation of Mineral and Dyes: A Laboratory Experiment for Separation Method Molecular Hitchhikers

ERIC Educational Resources Information Center

Rappon, Tim; Sylvestre, Jarrett A.; Rappon, Manit

2016-01-01

Flotation as a method of separation is widely researched and is applied in many industries. It has been used to address a wide range of environmental issues including treatment of wastewater, recovery of heavy metals for recycling, extraction of minerals in mining, and so forth. This laboratory attempts to show how such a simple method can be used…

Field metabolomics and laboratory assessments of anaerobic intrinsic bioremediation of hydrocarbons at a petroleum‐contaminated site

PubMed Central

Parisi, Victoria A.; Brubaker, Gaylen R.; Zenker, Matthew J.; Prince, Roger C.; Gieg, Lisa M.; Da Silva, Marcio L.B.; Alvarez, Pedro J. J.; Suflita, Joseph M.

2009-01-01

Summary Field metabolomics and laboratory assays were used to assess the in situ anaerobic attenuation of hydrocarbons in a contaminated aquifer underlying a former refinery. Benzene, ethylbenzene, 2‐methylnaphthalene, 1,2,4‐ and 1,3,5‐trimethylbenzene were targeted as contaminants of greatest regulatory concern (COC) whose intrinsic remediation has been previously reported. Metabolite profiles associated with anaerobic hydrocarbon decay revealed the microbial utilization of alkylbenzenes, including the trimethylbenzene COC, PAHs and several n‐alkanes in the contaminated portions of the aquifer. Anaerobic biodegradation experiments designed to mimic in situ conditions showed no loss of exogenously amended COC; however, a substantive rate of endogenous electron acceptor reduction was measured (55 ± 8 µM SO4 day−1). An assessment of hydrocarbon loss in laboratory experiments relative to a conserved internal marker revealed that non‐COC hydrocarbons were being metabolized. Purge and trap analysis of laboratory assays showed a substantial loss of toluene, m‐ and o‐xylene, as well as several alkanes (C6–C12). Multiple lines of evidence suggest that benzene is persistent under the prevailing site anaerobic conditions. We could find no in situ benzene intermediates (phenol or benzoate), the parent molecule proved recalcitrant in laboratory assays and low copy numbers of Desulfobacterium were found, a genus previously implicated in anaerobic benzene biodegradation. This study also showed that there was a reasonable correlation between field and laboratory findings, although with notable exception. Thus, while the intrinsic anaerobic bioremediation was clearly evident at the site, non‐COC hydrocarbons were preferentially metabolized, even though there was ample literature precedence for the biodegradation of the target molecules. PMID:21261914

Clogging of an Alpine streambed by silt-sized particles - Insights from laboratory and field experiments.

PubMed

Fetzer, Jasmin; Holzner, Markus; Plötze, Michael; Furrer, Gerhard

2017-12-01

Clogging of streambeds by suspended particles (SP) can cause environmental problems, as it can negatively influence, e.g., habitats for macrozoobenthos, fish reproduction and groundwater recharge. This especially applies in the case of silt-sized SP. Until now, most research has dealt with coarse SP and was carried out in laboratory systems. The aims of this study are to examine (1) whether physical clogging by silt-sized SP exhibits the same dynamics and patterns as by sand-sized SP, and (2) the comparability of results between laboratory and field experiments. We carried out vertical column experiments with sand-sized bed material and silt-sized SP, which are rich in mica minerals. In laboratory experiments, we investigated the degree of clogging quantified by the reduction of porosity and hydraulic conductivity and the maximum clogging depth as a function of size and shape of bed material, size of SP, pore water flow velocity, and concentration of calcium cations. The SP were collected from an Alpine sedimentation basin, where our field experiments were carried out. To investigate the clogging process in the field, we buried columns filled with sand-sized quartz in the stream bed. We found that the maximal bed-to-grain ratio where clogging still occurs is larger for silt-sized SP than for sand-sized SP. The observed clogging depths and the reduction of flow rate through the column from our laboratory experiments were comparable to those from the field. However, our field results showed that the extent of clogging strongly depends on the naturally-occurring hydrological dynamics. The field location was characterized by a more polydisperse suspension, a strongly fluctuating water regime, and high SP concentrations at times, leading to more heterogeneous and more pronounced clogging when compared to laboratory results. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Guided-inquiry laboratory experiments to improve students' analytical thinking skills

NASA Astrophysics Data System (ADS)

Wahyuni, Tutik S.; Analita, Rizki N.

2017-12-01

This study aims to improve the experiment implementation quality and analytical thinking skills of undergraduate students through guided-inquiry laboratory experiments. This study was a classroom action research conducted in three cycles. The study has been carried out with 38 undergraduate students of the second semester of Biology Education Department of State Islamic Institute (SII) of Tulungagung, as a part of Chemistry for Biology course. The research instruments were lesson plans, learning observation sheets and undergraduate students' experimental procedure. Research data were analyzed using quantitative-descriptive method. The increasing of analytical thinking skills could be measured using gain score normalized and statistical paired t-test. The results showed that guided-inquiry laboratory experiments model was able to improve both the experiment implementation quality and the analytical thinking skills. N-gain score of the analytical thinking skills was increased, in spite of just 0.03 with low increase category, indicated by experimental reports. Some of undergraduate students have had the difficulties in detecting the relation of one part to another and to an overall structure. The findings suggested that giving feedback the procedural knowledge and experimental reports were important. Revising the experimental procedure that completed by some scaffolding questions were also needed.

The Use of Microcomputer Based Laboratories in Chemistry Secondary Education: Present State of the Art and Ideas for Research-Based Practice

ERIC Educational Resources Information Center

Tortosa, Montserrat

2012-01-01

In microcomputer based laboratories (MBL) and data loggers, one or more sensors are connected to an interphase and this to a computer. This equipment allows visualization in real time of the variables of an experiment and provides the possibility of measuring magnitudes which are difficult to measure with traditional equipment. Research shows that…

Safety Precautions and Operating Procedures in an (A)BSL-4 Laboratory: 2. General Practices.

PubMed

Mazur, Steven; Holbrook, Michael R; Burdette, Tracey; Joselyn, Nicole; Barr, Jason; Pusl, Daniela; Bollinger, Laura; Coe, Linda; Jahrling, Peter B; Lackemeyer, Matthew G; Wada, Jiro; Kuhn, Jens H; Janosko, Krisztina

2016-10-03

Work in a biosafety level 4 (BSL-4) containment laboratory requires time and great attention to detail. The same work that is done in a BSL-2 laboratory with non-high-consequence pathogens will take significantly longer in a BSL-4 setting. This increased time requirement is due to a multitude of factors that are aimed at protecting the researcher from laboratory-acquired infections, the work environment from potential contamination and the local community from possible release of high-consequence pathogens. Inside the laboratory, movement is restricted due to air hoses attached to the mandatory full-body safety suits. In addition, disinfection of every item that is removed from Class II biosafety cabinets (BSCs) is required. Laboratory specialists must be trained in the practices of the BSL-4 laboratory and must show high proficiency in the skills they are performing. The focus of this article is to outline proper procedures and techniques to ensure laboratory biosafety and experimental accuracy using a standard viral plaque assay as an example procedure. In particular, proper techniques to work safely in a BSL-4 environment when performing an experiment will be visually emphasized. These techniques include: setting up a Class II BSC for experiments, proper cleaning of the Class II BSC when finished working, waste management and safe disposal of waste generated inside a BSL-4 laboratory, and the removal of inactivated samples from inside a BSL-4 laboratory to the BSL-2 laboratory.

Thermodynamics Fundamental Equation of a "Non-Ideal" Rubber Band from Experiments

ERIC Educational Resources Information Center

Ritacco, Herna´n A.; Fortunatti, Juan C.; Devoto, Walter; Ferna´ndez-Miconi, Eugenio; Dominguez, Claudia; Sanchez, Miguel D.

2014-01-01

In this paper, we describe laboratory and classroom exercises designed to obtain the "fundamental" equation of a rubber band by combining experiments and theory. The procedure shows students how classical thermodynamics formalism can help to obtain empirical equations of state by constraining and guiding in the construction of the…

The Adiabatic Expansion of Gases and the Determination of Heat Capacity Ratios: A Physical Chemistry Experiment.

ERIC Educational Resources Information Center

Moore, William M.

1984-01-01

Describes the procedures and equipment for an experiment on the adiabatic expansion of gases suitable for demonstration and discussion in the physical chemical laboratory. The expansion produced shows how the process can change temperature and still return to a different location on an isotherm. (JN)

Volcanology: Volcanic bipolar disorder explained

NASA Astrophysics Data System (ADS)

Jellinek, Mark

2014-02-01

Eruptions come in a range of magnitudes. Numerical simulations and laboratory experiments show that rare, giant super-eruptions and smaller, more frequent events reflect a transition in the essential driving forces for volcanism.

Laboratory constraints on models of earthquake recurrence

USGS Publications Warehouse

Beeler, Nicholas M.; Tullis, Terry; Junger, Jenni; Kilgore, Brian D.; Goldsby, David L.

2014-01-01

In this study, rock friction ‘stick-slip’ experiments are used to develop constraints on models of earthquake recurrence. Constant-rate loading of bare rock surfaces in high quality experiments produces stick-slip recurrence that is periodic at least to second order. When the loading rate is varied, recurrence is approximately inversely proportional to loading rate. These laboratory events initiate due to a slip rate-dependent process that also determines the size of the stress drop [Dieterich, 1979; Ruina, 1983] and as a consequence, stress drop varies weakly but systematically with loading rate [e.g., Gu and Wong, 1991; Karner and Marone, 2000; McLaskey et al., 2012]. This is especially evident in experiments where the loading rate is changed by orders of magnitude, as is thought to be the loading condition of naturally occurring, small repeating earthquakes driven by afterslip, or low-frequency earthquakes loaded by episodic slip. As follows from the previous studies referred to above, experimentally observed stress drops are well described by a logarithmic dependence on recurrence interval that can be cast as a non-linear slip-predictable model. The fault’s rate dependence of strength is the key physical parameter. Additionally, even at constant loading rate the most reproducible laboratory recurrence is not exactly periodic, unlike existing friction recurrence models. We present example laboratory catalogs that document the variance and show that in large catalogs, even at constant loading rate, stress drop and recurrence co-vary systematically. The origin of this covariance is largely consistent with variability of the dependence of fault strength on slip rate. Laboratory catalogs show aspects of both slip and time predictability and successive stress drops are strongly correlated indicating a ‘memory’ of prior slip history that extends over at least one recurrence cycle.

KENNEDY SPACE CENTER, FLA. - An overview of the Space Station Processing Facility shows workstands and ISS elements. The most recent additions are the Japanese Experiment Module (JEM)’s pressurized module and the Italian-built Node 2. The pressurized module is the first element of the JEM, Japan’s primary contribution to the Space Station, to be delivered to KSC. It will enhance the unique research capabilities of the orbiting complex by providing an additional shirt-sleeve environment for astronauts to conduct science experiments. Node 2 will be installed on the end of the U.S. Lab and provides attach locations for the Japanese laboratory, European laboratory, the Centrifuge Accommodation Module and, later, Multipurpose Logistics Modules. It will provide the primary docking location for the Shuttle when a pressurized mating adapter is attached to Node 2. Installation of the module will complete the U.S. Core of the ISS.

NASA Image and Video Library

2003-06-06

KENNEDY SPACE CENTER, FLA. - An overview of the Space Station Processing Facility shows workstands and ISS elements. The most recent additions are the Japanese Experiment Module (JEM)’s pressurized module and the Italian-built Node 2. The pressurized module is the first element of the JEM, Japan’s primary contribution to the Space Station, to be delivered to KSC. It will enhance the unique research capabilities of the orbiting complex by providing an additional shirt-sleeve environment for astronauts to conduct science experiments. Node 2 will be installed on the end of the U.S. Lab and provides attach locations for the Japanese laboratory, European laboratory, the Centrifuge Accommodation Module and, later, Multipurpose Logistics Modules. It will provide the primary docking location for the Shuttle when a pressurized mating adapter is attached to Node 2. Installation of the module will complete the U.S. Core of the ISS.

KENNEDY SPACE CENTER, FLA. - A view of the Space Station Processing Facility shows workstands and ISS elements. The most recent additions are the Japanese Experiment Module (JEM)’s pressurized module and the Italian-built Node 2. The pressurized module is the first element of the JEM, Japan’s primary contribution to the Space Station, to be delivered to KSC. It will enhance the unique research capabilities of the orbiting complex by providing an additional shirt-sleeve environment for astronauts to conduct science experiments. Node 2 will be installed on the end of the U.S. Lab and provides attach locations for the Japanese laboratory, European laboratory, the Centrifuge Accommodation Module and, later, Multipurpose Logistics Modules. It will provide the primary docking location for the Shuttle when a pressurized mating adapter is attached to Node 2. Installation of the module will complete the U.S. Core of the ISS.

NASA Image and Video Library

2003-06-06

KENNEDY SPACE CENTER, FLA. - A view of the Space Station Processing Facility shows workstands and ISS elements. The most recent additions are the Japanese Experiment Module (JEM)’s pressurized module and the Italian-built Node 2. The pressurized module is the first element of the JEM, Japan’s primary contribution to the Space Station, to be delivered to KSC. It will enhance the unique research capabilities of the orbiting complex by providing an additional shirt-sleeve environment for astronauts to conduct science experiments. Node 2 will be installed on the end of the U.S. Lab and provides attach locations for the Japanese laboratory, European laboratory, the Centrifuge Accommodation Module and, later, Multipurpose Logistics Modules. It will provide the primary docking location for the Shuttle when a pressurized mating adapter is attached to Node 2. Installation of the module will complete the U.S. Core of the ISS.

The principal Hugoniot of Mg2SiO4 to 950 GPa

NASA Astrophysics Data System (ADS)

Townsend, J. P.; Root, S.; Shulenburger, L.; Lemke, R. W.; Kraus, R. G.; Jacobsen, S. B.; Spaulding, D.; Davies, E.; Stewart, S. T.

2017-12-01

We present new measurements and ab-initio calculations of the principal Hugoniot states of forsterite Mg2SiO4 in the liquid regime between 200-950 GPa.Forsterite samples were shock compressed along the principal Hugoniot using plate-impact shock compression experiments on the Sandia National Laboratories Z machine facility.In order to gain insight into the physical state of the liquid, we performed quantum molecular dynamics calculations of the Hugoniot and compare the results to experiment.We show that the principal Hugoniot is consistent with that of a single molecular fluid phase of Mg2SiO4, and compare our results to previous dynamic compression experiments and QMD calculations.Finally, we discuss how the results inform planetary accretion and impact models.Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.

Birdcage volume coils and magnetic resonance imaging: a simple experiment for students.

PubMed

Vincent, Dwight E; Wang, Tianhao; Magyar, Thalia A K; Jacob, Peni I; Buist, Richard; Martin, Melanie

2017-01-01

This article explains some simple experiments that can be used in undergraduate or graduate physics or biomedical engineering laboratory classes to learn how birdcage volume radiofrequency (RF) coils and magnetic resonance imaging (MRI) work. For a clear picture, and to do any quantitative MRI analysis, acquiring images with a high signal-to-noise ratio (SNR) is required. With a given MRI system at a given field strength, the only means to change the SNR using hardware is to change the RF coil used to collect the image. RF coils can be designed in many different ways including birdcage volume RF coil designs. The choice of RF coil to give the best SNR for any MRI study is based on the sample being imaged. The data collected in the simple experiments show that the SNR varies as inverse diameter for the birdcage volume RF coils used in these experiments. The experiments were easily performed by a high school student, an undergraduate student, and a graduate student, in less than 3 h, the time typically allotted for a university laboratory course. The article describes experiments that students in undergraduate or graduate laboratories can perform to observe how birdcage volume RF coils influence MRI measurements. It is designed for students interested in pursuing careers in the imaging field.

U.S. Laboratory Module (Destiny) for the International Space Station

NASA Technical Reports Server (NTRS)

1998-01-01

This photograph shows the U.S. Laboratory Module (also called Destiny) for the International Space Station (ISS), in the Space Station manufacturing facility at the Marshall Space Flight Center, being readied for shipment to the Kennedy Space Center. The U.S. Laboratory module is the centerpiece of the ISS, where science experiments will be performed in the near-zero gravity of space. The Destiny Module was launched aboard the Space Shuttle orbiter Atlantis (STS-67 mission) on February 7, 2001. The aluminum module is 8.5 meters (28 feet) long and 4.3 meters (14 feet) in diameter. The laboratory consists of three cylindrical sections and two endcones with hatches that will be mated to other station components. A 50.9-centimeter- (20-inch-) diameter window is located on one side of the center module segment. This pressurized module is designed to accommodate pressurized payloads. It has a capacity of 24 rack locations, and payload racks will occupy 13 locations especially designed to support experiments. The ISS is a multidisciplinary laboratory, technology test bed, and observatory that will provide unprecedented undertakings in scientific, technological, and international experimentation.

U.S. Laboratory Module (Destiny) for the International Space Station

NASA Technical Reports Server (NTRS)

1997-01-01

This photograph shows the U.S. Laboratory Module (also called Destiny) for the International Space Station (ISS), under construction in the Space Station manufacturing facility at the Marshall Space Flight Center. The U.S. Laboratory module is the centerpiece of the ISS, where science experiments will be performed in the near-zero gravity of space. The Destiny Module was launched aboard the Space Shuttle orbiter Atlantis (STS-67 mission) on February 7, 2001. The aluminum module is 8.5 meters (28 feet) long and 4.3 meters (14 feet) in diameter. The laboratory consists of three cylindrical sections and two end cones with hatches that will be mated to other station components. A 50.9-centimeter- (20-inch-) diameter window is located on one side of the center module segment. This pressurized module is designed to accommodate pressurized payloads. It has a capacity of 24 rack locations, and payload racks will occupy 13 locations especially designed to support experiments. The ISS is a multidisciplinary laboratory, technology test bed, and observatory that will provide unprecedented undertakings in scientific, technological, and international experimentation.

Fault healing promotes high-frequency earthquakes in laboratory experiments and on natural faults

USGS Publications Warehouse

McLaskey, Gregory C.; Thomas, Amanda M.; Glaser, Steven D.; Nadeau, Robert M.

2012-01-01

Faults strengthen or heal with time in stationary contact and this healing may be an essential ingredient for the generation of earthquakes. In the laboratory, healing is thought to be the result of thermally activated mechanisms that weld together micrometre-sized asperity contacts on the fault surface, but the relationship between laboratory measures of fault healing and the seismically observable properties of earthquakes is at present not well defined. Here we report on laboratory experiments and seismological observations that show how the spectral properties of earthquakes vary as a function of fault healing time. In the laboratory, we find that increased healing causes a disproportionately large amount of high-frequency seismic radiation to be produced during fault rupture. We observe a similar connection between earthquake spectra and recurrence time for repeating earthquake sequences on natural faults. Healing rates depend on pressure, temperature and mineralogy, so the connection between seismicity and healing may help to explain recent observations of large megathrust earthquakes which indicate that energetic, high-frequency seismic radiation originates from locations that are distinct from the geodetically inferred locations of large-amplitude fault slip

Salt dissolution and sinkhole formation: Results of laboratory experiments

NASA Astrophysics Data System (ADS)

Oz, Imri; Eyal, Shalev; Yoseph, Yechieli; Ittai, Gavrieli; Elad, Levanon; Haim, Gvirtzman

2016-10-01

The accepted mechanism for the formation of thousands of sinkholes along the coast of the Dead Sea suggests that their primary cause is dissolution of a salt layer by groundwater undersaturated with respect to halite. This is related to the drop in the Dead Sea level, which caused a corresponding drop of the freshwater-saltwater interface, resulting in fresher groundwater replacing the brines that were in contact with the salt layer. In this study we used physical laboratory experiments to examine the validity of this mechanism by reproducing the full dynamic natural process and to examine the impact of different hydrogeological characteristics on this process. The experimental results show surface subsidence and sinkhole formation. The stratigraphic configurations of the aquifer, together with the mechanical properties of the salt layer, determine the dynamic patterns of the sinkhole formation (instantaneous versus gradual formation). Laboratory experiments were also used to study the potential impact of future stratification in the Dead Sea, if and when the "Red Sea-Dead Sea Canal" project is carried out, and the Dead Sea level remains stable. The results show that the dissolution rates are slower by 1 order of magnitude in comparison with a nonstratified saltwater body, and therefore, the processes of salt dissolution and sinkhole formation will be relatively restrained under these conditions.

The relationship between internet-gaming experience and executive functions measured by virtual environment compared with conventional laboratory multitasks.

PubMed

Chen, Yong-Quan; Hsieh, Shulan

2018-01-01

The aim of this study was to investigate if individuals with frequent internet gaming (IG) experience exhibited better or worse multitasking ability compared with those with infrequent IG experience. The individuals' multitasking abilities were measured using virtual environment multitasks, such as Edinburgh Virtual Errands Test (EVET), and conventional laboratory multitasks, such as the dual task and task switching. Seventy-two young healthy college students participated in this study. They were split into two groups based on the time spent on playing online games, as evaluated using the Internet Use Questionnaire. Each participant performed EVET, dual-task, and task-switching paradigms on a computer. The current results showed that the frequent IG group performed better on EVET compared with the infrequent IG group, but their performance on the dual-task and task-switching paradigms did not differ significantly. The results suggest that the frequent IG group exhibited better multitasking efficacy if measured using a more ecologically valid task, but not when measured using a conventional laboratory multitasking task. The differences in terms of the subcomponents of executive function measured by these task paradigms were discussed. The current results show the importance of the task effect while evaluating frequent internet gamers' multitasking ability.

The relationship between internet-gaming experience and executive functions measured by virtual environment compared with conventional laboratory multitasks

PubMed Central

Chen, Yong-Quan

2018-01-01

The aim of this study was to investigate if individuals with frequent internet gaming (IG) experience exhibited better or worse multitasking ability compared with those with infrequent IG experience. The individuals’ multitasking abilities were measured using virtual environment multitasks, such as Edinburgh Virtual Errands Test (EVET), and conventional laboratory multitasks, such as the dual task and task switching. Seventy-two young healthy college students participated in this study. They were split into two groups based on the time spent on playing online games, as evaluated using the Internet Use Questionnaire. Each participant performed EVET, dual-task, and task-switching paradigms on a computer. The current results showed that the frequent IG group performed better on EVET compared with the infrequent IG group, but their performance on the dual-task and task-switching paradigms did not differ significantly. The results suggest that the frequent IG group exhibited better multitasking efficacy if measured using a more ecologically valid task, but not when measured using a conventional laboratory multitasking task. The differences in terms of the subcomponents of executive function measured by these task paradigms were discussed. The current results show the importance of the task effect while evaluating frequent internet gamers’ multitasking ability. PMID:29879150

What is the purpose of this experiment? Or can students learn something from doing experiments?

NASA Astrophysics Data System (ADS)

Hart, Christina; Mulhall, Pamela; Berry, Amanda; Loughran, John; Gunstone, Richard

2000-09-01

Historically there have been many claims made about the value of laboratory work in schools, yet research shows that it often achieves little meaningful learning by students. One reason, among many, for this failing is that students often do not know the purposes for these tasks. By purposes we mean the intentions the teacher has for the activity when she/he decides to use it with a particular class at a particular time. This we contrast with the aims of a laboratory activity, the often quite formalised statements about the intended endpoint of the activity that are too often the opening lines of a student laboratory report and are simply the expected specific science content knowledge outcomes - not necessarily learnt nor understood. This paper describes a unit of laboratory work which was unusual in that the teacher's purpose was to develop students' understanding about the way scientific facts are established with little expectation that they would understand the science content involved in the experiments. The unit was very successful from both a cognitive and affective perspective. An important feature was the way in which students gradually came to understand the teacher's purpose as they proceeded through the unit.

Knowledge Retention for Computer Simulations: A study comparing virtual and hands-on laboratories

NASA Astrophysics Data System (ADS)

Croom, John R., III

The use of virtual laboratories has the potential to change physics education. These low-cost, interactive computer activities interest students, allow for easy setup, and give educators a way to teach laboratory based online classes. This study investigated whether virtual laboratories could replace traditional hands-on laboratories and whether students could retain the same long-term knowledge in virtual laboratories as compared to hands-on laboratories. This study is a quantitative quasi-experiment that used a multiple posttest design to determine if students using virtual laboratories would retain the same knowledge as students who performed hands-on laboratories after 9 weeks. The study was composed of 336 students from 14 school districts. Students had their performances on the laboratories and their retention of the laboratories compared to a series of factors that might have affected their retention using a pretest and two posttests, which were compared using a t test. The results showed no significant difference in short-term learning between the hands-on laboratory groups and virtual laboratory groups. There was, however, a significant difference (p = .005) between the groups in long-term retention; students in the hands-on laboratory groups retained more information than those in the virtual laboratory groups. These results suggest that long-term learning is enhanced when a laboratory contains a hands-on component. Finally, the results showed that both groups of students felt their particular laboratory style was superior to the alternative method. The findings of this study can be used to improve the integration of virtual laboratories into science curriculum.

Microbial Removal of the Pharmaceutical Compounds Ibuprofen and Diclofenac from Wastewater

PubMed Central

Inderfurth, Nadia; Schraa, Gosse; Kujawa-Roeleveld, Katarzyna; Rijnaarts, Huub

2013-01-01

Studies on the occurrence of pharmaceuticals show that the widely used pharmaceuticals ibuprofen and diclofenac are present in relevant concentrations in the environment. A pilot plant treating hospital wastewater with relevant concentrations of these pharmaceuticals was evaluated for its performance to reduce the concentration of the pharmaceuticals. Ibuprofen was completely removed, whereas diclofenac yielded a residual concentration, showing the necessity of posttreatment to remove diclofenac, for example, activated carbon. Successively, detailed laboratory experiments with activated sludge from the same wastewater treatment plant showed bioremediation potential in the treatment plant. The biological degradation pathway was studied and showed a mineralisation of ibuprofen and degradation of diclofenac. The present microbes were further studied in laboratory experiments, and DGGE analyses showed the enrichment and isolation of highly purified cultures that degraded either ibuprofen or diclofenac. This research illuminates the importance of the involved bacteria for the effectiveness of the removal of pharmaceuticals in a wastewater treatment plant. A complete removal of pharmaceuticals from wastewater will stimulate water reuse, addressing the worldwide increasing demand for clean and safe fresh water. PMID:24350260

Effects of tributyltin on the MFO system of the clam Ruditapes decussata: a laboratory and field approach.

PubMed

Solé, M

2000-01-01

The in vivo interaction of tributyltin (TBT) with the microsomal monooxygenase (MFO) system of the clam Ruditapes decussata was studied. For this purpose, two experiments were designed: (1) a laboratory exposure to increasing nominal doses of TBT (90, 454 and 2268 ng l(-1)) for 1 week and (2) a clam transplant from a clean area to an organotin polluted marina for periods of up to 5 weeks. Chemical analysis of organotins in clam tissue was used to relate TBT body burden to the MFO response. Neither the laboratory nor the field transplant experiment showed any significant TBT effect on the clam's digestive gland MFO components (cytochrome P450 and cytochrome b(5)). However, a significant elevation in the NADPH cytochrome (P450) reductases at the low and medium TBT doses in the laboratory and a significant decrease in NADH cytochrome (b(5)) reductases, 1 week after the field transplant, was observed with further recovery to control levels thereafter.

Simulations of a Molecular Cloud experiment using CRASH

NASA Astrophysics Data System (ADS)

Trantham, Matthew; Keiter, Paul; Vandervort, Robert; Drake, R. Paul; Shvarts, Dov

2017-10-01

Recent laboratory experiments explore molecular cloud radiation hydrodynamics. The experiment irradiates a gold foil with a laser producing x-rays to drive the implosion or explosion of a foam ball. The CRASH code, an Eulerian code with block-adaptive mesh refinement, multigroup diffusive radiation transport, and electron heat conduction developed at the University of Michigan to design and analyze high-energy-density experiments, is used to perform a parameter search in order to identify optically thick, optically thin and transition regimes suitable for these experiments. Specific design issues addressed by the simulations are the x-ray drive temperature, foam density, distance from the x-ray source to the ball, as well as other complicating issues such as the positioning of the stalk holding the foam ball. We present the results of this study and show ways the simulations helped improve the quality of the experiment. This work is funded by the LLNL under subcontract B614207 and NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, Grant Number DE-NA0002956.

Food intake in laboratory rats provided standard and fenbendazole-supplemented diets.

PubMed

Vento, Peter J; Swartz, Megan E; Martin, Lisa Be; Daniels, Derek

2008-11-01

The benzimidazole anthelmintic fenbendazole (FBZ) is a common and effective treatment for pinworm infestation in laboratory animal colonies. Although many investigators have examined the potential for deleterious biologic effects of FBZ, more subtle aspects of the treatment remain untested. Accordingly, we evaluated differences in food intake when healthy male Sprague-Dawley rats were provided a standard nonmedicated laboratory rodent chow or the same chow supplemented with FBZ. We also tested for a preference for either food type when subjects were provided a choice of the 2 diets. Data from these experiments showed no differences in food intake or body weight when rats were maintained on either standard or FBZ-supplemented chow. When the rats were given access to both the standard and FBZ-supplemented diets, they showed a clear preference for the standard diet. The preference for the standard diet indicates that the rats can discriminate between the 2 foods and may avoid the FBZ-supplemented chow when possible. Investigators conducting experiments during treatment with FBZ in which differences in food preference are relevant should be aware of these data and plan their studies accordingly.

Food Intake in Laboratory Rats Provided Standard and Fenbendazole-supplemented Diets

PubMed Central

Vento, Peter J; Swartz, Meghan E; Martin, Lisa BE; Daniels, Derek

2008-01-01

The benzimidazole anthelmintic fenbendazole (FBZ) is a common and effective treatment for pinworm infestation in laboratory animal colonies. Although many investigators have examined the potential for deleterious biologic effects of FBZ, more subtle aspects of the treatment remain untested. Accordingly, we evaluated differences in food intake when healthy male Sprague–Dawley rats were provided a standard nonmedicated laboratory rodent chow or the same chow supplemented with FBZ. We also tested for a preference for either food type when subjects were provided a choice of the 2 diets. Data from these experiments showed no differences in food intake or body weight when rats were maintained on either standard or FBZ-supplemented chow. When the rats were given access to both the standard and FBZ-supplemented diets, they showed a clear preference for the standard diet. The preference for the standard diet indicates that the rats can discriminate between the 2 foods and may avoid the FBZ-supplemented chow when possible. Investigators conducting experiments during treatment with FBZ in which differences in food preference are relevant should be aware of these data and plan their studies accordingly. PMID:19049253

Ecological Studies of Plants.

ERIC Educational Resources Information Center

Sutherland, William J.; Watkinson, Andrew R.

1988-01-01

Suggests an approach and methodology for analyzing field and laboratory populations. Describes an experiment using mustard to show how competition and inequality can be assessed. Discusses the variables responsible for determining the abundance of organisms. (CW)

Art, outreach and geopattern formation

NASA Astrophysics Data System (ADS)

Morris, S. W.; Chen, A. S. H.; Rogers, M. C.; Goehring, L.

2014-12-01

For the past several years, I have been exhibiting images and videos of natural and laboratory geopatterns in art galleries and outdoor shows. I have also brought artists into my research lab for hands-on workshops. My experience shows that scientific images can be well received as art and generate wide-ranging discussions across traditionally separate disciplines. The art world offers an interesting new venue for outreach activities, as well as being a lot of fun to explore. Artists Statement:I am interested in self-organized, emergent patterns and textures. I take photos of patterns both from the natural world and of experiments in my laboratory in the department of Physics at the University of Toronto. Patterns naturally attract casual attention but are also the subject of serious scientific research. Some things just evolve all by themselves into strikingly regular shapes and textures. Why? These shapes emerge spontaneously from a dynamic process of growing, folding, cracking, wrinkling, branching, flowing and other kinds of morphological development. My photos are informed by the scientific aesthetic of nonlinear physics, and mathematics lurks behind every image for those who know where to look for it. But no special knowledge is required to appreciate the results. Each image shows an object, sometimes quite small and often familiar, with a self-composed regular structure. Some images are from laboratory physics experiments and some are from Nature, and all celebrate the subtle interplay of order and complexity in emergent patterns.

Effectiveness of the Flipped Classroom Model in Anatomy and Physiology Laboratory Courses at a Hispanic Serving Institution

NASA Astrophysics Data System (ADS)

Sanchez, Gerardo

A flipped laboratory model involves significant preparation by the students on lab material prior to entry to the laboratory. This allows laboratory time to be focused on active learning through experiments. The aim of this study was to observe changes in student performance through the transition from a traditional laboratory format, to a flipped format. The data showed that for both Anatomy and Physiology (I and II) laboratories a more normal distribution of grades was observed once labs were flipped and lecture grade averages increased. Chi square and analysis of variance tests showed grade changes to a statistically significant degree, with a p value of less than 0.05 on both analyses. Regression analyses gave decreasing numbers after the flipped labs were introduced with an r. 2 value of .485 for A&P I, and .564 for A&P II. Results indicate improved scores for the lecture part of the A&P course, decreased outlying scores above 100, and all score distributions approached a more normal distribution.

Laboratory simulation of Hg0 emissions from a snowpack.

PubMed

Dommergue, Aurélien; Bahlmann, Enno; Ebinghaus, Ralf; Ferrari, Christophe; Boutron, Claude

2007-05-01

Snow surfaces play an important role in the biogeochemical cycle of mercury in high-latitude regions. Snowpacks act both as sources and sinks for gaseous compounds. Surprisingly, the roles of each environmental parameter that can govern the air-surface exchange over snow are not well understood owing to the lack of systematic studies. A laboratory system called the laboratory flux measurement system was used to study the emission of gaseous elemental mercury from a natural snowpack under controlled conditions. The first results from three snowpacks originating from alpine, urban and polar areas are presented. Consistent with observations in the field, we were able to reproduce gaseous mercury emissions and showed that they are mainly driven by solar radiation and especially UV-B radiation. From these laboratory experiments, we derived kinetic constants which show that divalent mercury can have a short natural lifetime of about 4-6 h in snow.

IRON PRECIPITATION AND ARSENIC ATTENUATION - ASSESSMENT OF ARSENIC NATURAL ATTENUATION OF THE SUBSURFACE USING A GEOCHEMICAL MODEL (PHREEQC)

EPA Science Inventory

Laboratory experiments show that amorphous and poorly crystallized ferric iron hydroxides have much greater capacity to attenuate arsenic compared to clays and other aluminosilicate minerals. Studies (e.g., Lin and Qvarfort, 1996) showed that a sudden change in geochemical condit...

A model of electron collecting plasma contractors

NASA Technical Reports Server (NTRS)

Davis, V. A.; Katz, I.; Mandell, M. J.; Parks, D. E.

1989-01-01

A model of plasma contractors is being developed, which can be used to describe electron collection in a laboratory test tank and in the space environment. To validate the model development, laboratory experiments are conducted in which the source plasma is separated from the background plasma by a double layer. Model calculations show that an increase in ionization rate with potential produces a steep rise in collected current with increasing potential.

Art in Time and Space: Context Modulates the Relation between Art Experience and Viewing Time

PubMed Central

Brieber, David; Nadal, Marcos; Leder, Helmut; Rosenberg, Raphael

2014-01-01

The experience of art emerges from the interaction of various cognitive and affective processes. The unfolding of these processes in time and their relation with viewing behavior, however, is still poorly understood. Here we examined the effect of context on the relation between the experience of art and viewing time, the most basic indicator of viewing behavior. Two groups of participants viewed an art exhibition in one of two contexts: one in the museum, the other in the laboratory. In both cases viewing time was recorded with a mobile eye tracking system. After freely viewing the exhibition, participants rated each artwork on liking, interest, understanding, and ambiguity scales. Our results show that participants in the museum context liked artworks more, found them more interesting, and viewed them longer than those in the laboratory. Analyses with mixed effects models revealed that aesthetic appreciation (compounding liking and interest), understanding, and ambiguity predicted viewing time for artworks and for their corresponding labels. The effect of aesthetic appreciation and ambiguity on viewing time was modulated by context: Whereas art appreciation tended to predict viewing time better in the laboratory than in museum context, the relation between ambiguity and viewing time was positive in the museum and negative in the laboratory context. Our results suggest that art museums foster an enduring and focused aesthetic experience and demonstrate that context modulates the relation between art experience and viewing behavior. PMID:24892829

Constraints on the rheology of the partially molten mantle from numerical models of laboratory experiments

NASA Astrophysics Data System (ADS)

Rudge, J. F.; Alisic Jewell, L.; Rhebergen, S.; Katz, R. F.; Wells, G. N.

2015-12-01

One of the fundamental components in any dynamical model of melt transport is the rheology of partially molten rock. This rheology is poorly understood, and one way in which a better understanding can be obtained is by comparing the results of laboratory deformation experiments to numerical models. Here we present a comparison between numerical models and the laboratory setup of Qi et al. 2013 (EPSL), where a cylinder of partially molten rock containing rigid spherical inclusions was placed under torsion. We have replicated this setup in a finite element model which solves the partial differential equations describing the mechanical process of compaction. These computationally-demanding 3D simulations are only possible due to the recent development of a new preconditioning method for the equations of magma dynamics. The experiments show a distinct pattern of melt-rich and melt-depleted regions around the inclusions. In our numerical models, the pattern of melt varies with key rheological parameters, such as the ratio of bulk to shear viscosity, and the porosity- and strain-rate-dependence of the shear viscosity. These observed melt patterns therefore have the potential to constrain rheological properties. While there are many similarities between the experiments and the numerical models, there are also important differences, which highlight the need for better models of the physics of two-phase mantle/magma dynamics. In particular, the laboratory experiments display more pervasive melt-rich bands than is seen in our numerics.

Art in time and space: context modulates the relation between art experience and viewing time.

PubMed

Brieber, David; Nadal, Marcos; Leder, Helmut; Rosenberg, Raphael

2014-01-01

The experience of art emerges from the interaction of various cognitive and affective processes. The unfolding of these processes in time and their relation with viewing behavior, however, is still poorly understood. Here we examined the effect of context on the relation between the experience of art and viewing time, the most basic indicator of viewing behavior. Two groups of participants viewed an art exhibition in one of two contexts: one in the museum, the other in the laboratory. In both cases viewing time was recorded with a mobile eye tracking system. After freely viewing the exhibition, participants rated each artwork on liking, interest, understanding, and ambiguity scales. Our results show that participants in the museum context liked artworks more, found them more interesting, and viewed them longer than those in the laboratory. Analyses with mixed effects models revealed that aesthetic appreciation (compounding liking and interest), understanding, and ambiguity predicted viewing time for artworks and for their corresponding labels. The effect of aesthetic appreciation and ambiguity on viewing time was modulated by context: Whereas art appreciation tended to predict viewing time better in the laboratory than in museum context, the relation between ambiguity and viewing time was positive in the museum and negative in the laboratory context. Our results suggest that art museums foster an enduring and focused aesthetic experience and demonstrate that context modulates the relation between art experience and viewing behavior.

Laboratory chalcopyrite oxidation by Acidithiobacillus ferrooxidans: Oxygen and sulfur isotope fractionation

USGS Publications Warehouse

Thurston, R.S.; Mandernack, K.W.; Shanks, Wayne C.

2010-01-01

Laboratory experiments were conducted to simulate chalcopyrite oxidation under anaerobic and aerobic conditions in the absence or presence of the bacterium Acidithiobacillus ferrooxidans. Experiments were carried out with 3 different oxygen isotope values of water (??18OH2O) so that approach to equilibrium or steady-state isotope fractionation for different starting conditions could be evaluated. The contribution of dissolved O2 and water-derived oxygen to dissolved sulfate formed by chalcopyrite oxidation was unambiguously resolved during the aerobic experiments. Aerobic oxidation of chalcopyrite showed 93 ?? 1% incorporation of water oxygen into the resulting sulfate during the biological experiments. Anaerobic experiments showed similar percentages of water oxygen incorporation into sulfate, but were more variable. The experiments also allowed determination of sulfate-water oxygen isotope fractionation, ??18OSO4-H2O, of ~ 3.8??? for the anaerobic experiments. Aerobic oxidation produced apparent ??SO4-H2O values (6.4???) higher than the anaerobic experiments, possibly due to additional incorporation of dissolved O2 into sulfate. ??34SSO4 values are ~ 4??? lower than the parent sulfide mineral during anaerobic oxidation of chalcopyrite, with no significant difference between abiotic and biological processes. For the aerobic experiments, a small depletion in ??34SSO4 of ~- 1.5 ?? 0.2??? was observed for the biological experiments. Fewer solids precipitated during oxidation under aerobic conditions than under anaerobic conditions, which may account for the observed differences in sulfur isotope fractionation under these contrasting conditions. ?? 2009 Elsevier B.V.

Rapid Association Learning in the Primate Prefrontal Cortex in the Absence of Behavioral Reversals

ERIC Educational Resources Information Center

Cromer, Jason A.; Machon, Michelle; Miller, Earl K.

2011-01-01

The PFC plays a central role in our ability to learn arbitrary rules, such as "green means go." Previous experiments from our laboratory have used conditional association learning to show that slow, gradual changes in PFC neural activity mirror monkeys' slow acquisition of associations. These previous experiments required monkeys to repeatedly…

Using the Computer as a Laboratory Instrument.

ERIC Educational Resources Information Center

Collings, Peter J.; Greenslade, Thomas B., Jr.

1989-01-01

Reports experiences during a two-year period in introducing the computer to the laboratory and students to the computer as a laboratory instrument. Describes a working philosophy, data acquisition system, and experiments. Summarizes the laboratory procedures of nine experiments, covering mechanics, heat, electromagnetism, and optics. (YP)

Exploratory study of the acceptance of two individual practical classes with remote labs

NASA Astrophysics Data System (ADS)

Tirado-Morueta, Ramón; Sánchez-Herrera, Reyes; Márquez-Sánchez, Marco A.; Mejías-Borrero, Andrés; Andujar-Márquez, José Manuel

2018-03-01

Remote lab experiences are proliferating in higher education, although there are still few studies that manage to build a theoretical framework for educational assessment and design of this technology. In order to explore to what extent the use of facilitators of proximity to the laboratory and the autonomy of the experiment makes remote laboratories a technology accepted by students, two remote labs different yet similar educational conditions in laboratories are used. A sample of 98 undergraduate students from a degree course in Energy Engineering was used for this study; 57 of these students ran experiments in a laboratory of electrical machines and 41 in a photovoltaic systems laboratory. The data suggest using conditions that facilitate the proximity of the laboratory and the autonomy in the realisation of the experiment; in both laboratories the experience was positively valued by the students. Also, data suggest that the types of laboratory and experiment have influences on usability - autonomy and lab proximity - perceived by students.

Earthquake rupture dynamics in poorly lithified sediments

NASA Astrophysics Data System (ADS)

De Paola, N.; Bullock, R. J.; Holdsworth, R.; Marco, S.; Nielsen, S. B.

2017-12-01

Several recent large earthquakes have generated anomalously large slip patches when propagating through fluid-saturated, clay-rich sediments near the surface. Friction experiments at seismic slip rates show that such sediments are extremely weak and deform with very little energy dissipation, which facilitates rupture propagation. Although dynamic weakening may explain the ease of rupture propagation through such sediments, it cannot account for the peculiar slow rupture velocity and low radiation efficiency exhibited by some large, shallow ruptures. Here, we integrate field and experimental datasets to describe on- and off-fault deformation in natural syn-depositional seismogenic faults (< 35 ka) in shallow, clay-rich, poorly lithified sediments from the Dead Sea Fault system, Israel. The data are then used to estimate the energy dissipated by on- and off-fault damage during earthquake rupture through shallow, clay-rich sediments. Our mechanical and field data show localised principal slip zones (PSZs) that deform by particulate flow, with little energy dissipated by brittle fracturing with cataclasis. Conversely, we show that coseismic brittle and ductile deformation in the damage zones outwith the PSZ, which cannot be replicated in small-scale laboratory experiments, is a significant energy sink, contributing to an energy dissipation that is one order of magnitude greater than that estimated from laboratory experiments alone. In particular, a greater proportion of dissipated energy would result in lower radiation efficiency, due to a reduced proportion of radiated energy, plus slower rupture velocity and more energy radiation in the low frequency range than might be anticipated from laboratory experiments alone. This result is in better agreement with seismological estimates of fracture energy, implying that off-fault damage can account for the geophysical characteristics of earthquake ruptures as they pass through clay-rich sediments in the shallow crust.

Adding Audio Supported Smartboard Lectures to an Introductory Astronomy Online Laboratory

NASA Astrophysics Data System (ADS)

Lahaise, U. G. L.

2003-12-01

SMART Board(TM) and RealProducer(R) Plus technologies were used to develop a series of narrated pre-lab introductory online lectures. Smartboard slides were created by capturing images from internet pages and power point slides, then annotated and saved as web pages using smartboard technology. Short audio files were recorded using the RealProducer Plus software which were then linked to individual slides. WebCT was used to deliver the online laboratory. Students in an Introductory Astronomy of the Solar System Online laboratory used the lectures to prepare for laboratory exercises. The narrated pre-lab lectures were added to six out of eight suitable laboratory exercises. A survey was given to the students to research their online laboratory experience, in general, and the impact of the narrated smartboard lectures on their learning success, specifically. Data were collected for two accelerated sessions. Results show that students find the online laboratory equally hard or harder than a separate online lecture. The accelerated format created great time pressure which negatively affected their study habits. About half of the students used the narrated pre-lab lectures consistently. Preliminary findings show that lab scores in the accelerated sessions were brought up to the level of full semester courses.

Zero-gravity cloud physics laboratory: Experiment program definition and preliminary laboratory concept studies

NASA Technical Reports Server (NTRS)

Eaton, L. R.; Greco, E. V.

1973-01-01

The experiment program definition and preliminary laboratory concept studies on the zero G cloud physics laboratory are reported. This program involves the definition and development of an atmospheric cloud physics laboratory and the selection and delineations of a set of candidate experiments that must utilize the unique environment of zero gravity or near zero gravity.

Successful Sampling Strategy Advances Laboratory Studies of NMR Logging in Unconsolidated Aquifers

NASA Astrophysics Data System (ADS)

Behroozmand, Ahmad A.; Knight, Rosemary; Müller-Petke, Mike; Auken, Esben; Barfod, Adrian A. S.; Ferré, Ty P. A.; Vilhelmsen, Troels N.; Johnson, Carole D.; Christiansen, Anders V.

2017-11-01

The nuclear magnetic resonance (NMR) technique has become popular in groundwater studies because it responds directly to the presence and mobility of water in a porous medium. There is a need to conduct laboratory experiments to aid in the development of NMR hydraulic conductivity models, as is typically done in the petroleum industry. However, the challenge has been obtaining high-quality laboratory samples from unconsolidated aquifers. At a study site in Denmark, we employed sonic drilling, which minimizes the disturbance of the surrounding material, and extracted twelve 7.6 cm diameter samples for laboratory measurements. We present a detailed comparison of the acquired laboratory and logging NMR data. The agreement observed between the laboratory and logging data suggests that the methodologies proposed in this study provide good conditions for studying NMR measurements of unconsolidated near-surface aquifers. Finally, we show how laboratory sample size and condition impact the NMR measurements.

Tempered glass and thermal shock of ceramic materials

NASA Technical Reports Server (NTRS)

Bunnell, L. Roy

1992-01-01

A laboratory experiment is described that shows students the different strengths and fracture toughnesses between tempered and untempered glass. This paper also describes how glass is tempered and the materials science aspects of the process.

Estimating Fault Friction From Seismic Signals in the Laboratory

NASA Astrophysics Data System (ADS)

Rouet-Leduc, Bertrand; Hulbert, Claudia; Bolton, David C.; Ren, Christopher X.; Riviere, Jacques; Marone, Chris; Guyer, Robert A.; Johnson, Paul A.

2018-02-01

Nearly all aspects of earthquake rupture are controlled by the friction along the fault that progressively increases with tectonic forcing but in general cannot be directly measured. We show that fault friction can be determined at any time, from the continuous seismic signal. In a classic laboratory experiment of repeating earthquakes, we find that the seismic signal follows a specific pattern with respect to fault friction, allowing us to determine the fault's position within its failure cycle. Using machine learning, we show that instantaneous statistical characteristics of the seismic signal are a fingerprint of the fault zone shear stress and frictional state. Further analysis of this fingerprint leads to a simple equation of state quantitatively relating the seismic signal power and the friction on the fault. These results show that fault zone frictional characteristics and the state of stress in the surroundings of the fault can be inferred from seismic waves, at least in the laboratory.

Laboratory plasma interactions experiments: Results and implications to future space systems

NASA Technical Reports Server (NTRS)

Leung, Philip

1986-01-01

The experimental results discussed show the significance of the effects caused by spacecraft plasma interactions, in particular the generation of Electromagnetic Interference. As the experimental results show, the magnitude of the adverse effects induced by Plasma Interactions (PI) will be more significant for spacecraft of the next century. Therefore, research is needed to control possible adverse effects. Several techniques to control the selected PI effects are discussed. Tests, in the form of flight experiments, are needed to validate these proposed ideas.

A new method for eliciting three speaking styles in the laboratory

PubMed Central

Harnsberger, James D.; Wright, Richard; Pisoni, David B.

2009-01-01

In this study, a method was developed to elicit three different speaking styles, reduced, citation, and hyperarticulated, using controlled sentence materials in a laboratory setting. In the first set of experiments, the reduced style was elicited by having twelve talkers read a sentence while carrying out a distractor task that involved recalling from short-term memory an individually-calibrated number of digits. The citation style corresponded to read speech in the laboratory. The hyperarticulated style was elicited by prompting talkers (twice) to reread the sentences more carefully. The results of perceptual tests with naïve listeners and an acoustic analysis showed that six of the twelve talkers produced a reduced style of speech for the test sentences in the distractor task relative to the same sentences in the citation style condition. In addition, all talkers consistently produced sentences in the citation and hyperarticulated styles. In the second set of experiments, the reduced style was elicited by increasing the number of digits in the distractor task by one (a heavier cognitive load). The procedures for eliciting citation and hyperarticulated sentences remained unchanged. Ten talkers were recorded in the second experiment. The results showed that six out of ten talkers differentiated all three styles as predicted (70% of all sentences recorded). In addition, all talkers consistently produced sentences in the citation and hyperarticulated styles. Overall, the results demonstrate that it is possible to elicit controlled sentence stimulus materials varying in speaking style in a laboratory setting, although the method requires further refinement to elicit these styles more consistently from individual participants. PMID:19562041

A new method for eliciting three speaking styles in the laboratory.

PubMed

Harnsberger, James D; Wright, Richard; Pisoni, David B

2008-04-01

In this study, a method was developed to elicit three different speaking styles, reduced, citation, and hyperarticulated, using controlled sentence materials in a laboratory setting. In the first set of experiments, the reduced style was elicited by having twelve talkers read a sentence while carrying out a distractor task that involved recalling from short-term memory an individually-calibrated number of digits. The citation style corresponded to read speech in the laboratory. The hyperarticulated style was elicited by prompting talkers (twice) to reread the sentences more carefully. The results of perceptual tests with naïve listeners and an acoustic analysis showed that six of the twelve talkers produced a reduced style of speech for the test sentences in the distractor task relative to the same sentences in the citation style condition. In addition, all talkers consistently produced sentences in the citation and hyperarticulated styles. In the second set of experiments, the reduced style was elicited by increasing the number of digits in the distractor task by one (a heavier cognitive load). The procedures for eliciting citation and hyperarticulated sentences remained unchanged. Ten talkers were recorded in the second experiment. The results showed that six out of ten talkers differentiated all three styles as predicted (70% of all sentences recorded). In addition, all talkers consistently produced sentences in the citation and hyperarticulated styles. Overall, the results demonstrate that it is possible to elicit controlled sentence stimulus materials varying in speaking style in a laboratory setting, although the method requires further refinement to elicit these styles more consistently from individual participants.

Rhodamine-WT dye losses in a mountain stream environment

USGS Publications Warehouse

Bencala, Kenneth E.; Rathburn, Ronald E.; Jackman, Alan P.; Kennedy, Vance C.; Zellweger, Gary W.; Avanzino, Ronald J.

1983-01-01

A significant fraction of rhodamine WT dye was lost during a short term multitracer injection experiment in a mountain stream environment. The conservative anion chloride and the sorbing cation lithium were concurrently injected. In-stream rhodamine WT concentrations were as low as 45 percent of that expected, based on chloride data. Concentration data were available from shallow‘wells’dug near the stream course and from a seep of suspected return flow. Both rhodamine WT dye and lithium were nonconservative with respect to the conservative chloride, with rhodamine WT dye closely following the behavior of the sorbing lithium.Nonsorption and sorption mechanisms for rhodamine WT loss in a mountain stream were evaluated in laboratory experiments. Experiments evaluating nonsorption losses indicated minimal losses by such mechanisms. Laboratory experiments using sand and gravel size streambed sediments show an appreciable capacity for rhodamine WT sorption.The detection of tracers in the shallow wells and seep indicates interaction between the stream and the flow in the surrounding subsurface, intergravel water, system. The injected tracers had ample opportunity for intimate contact with materials shown in the laboratory experiments to be potentially sorptive. It is suggested that in the study stream system, interaction with streambed gravel was a significant mechanism for the attenuation of rhodamine WT dye (relative to chloride).

Design of laboratory experiments to study radiation-driven implosions

DOE PAGES

Keiter, P. A.; Trantham, M.; Malamud, G.; ...

2017-02-03

The interstellar medium is heterogeneous with dense clouds amid an ambient medium. Radiation from young OB stars asymmetrically irradiate the dense clouds. Bertoldi (1989) developed analytic formulae to describe possible outcomes of these clouds when irradiated by hot, young stars. One of the critical parameters that determines the cloud’s fate is the number of photon mean free paths in the cloud. For the extreme cases where the cloud size is either much greater than or much less than one mean free path, the radiation transport should be well understood. However, as one transitions between these limits, the radiation transport ismore » much more complex and is a challenge to solve with many of the current radiation transport models implemented in codes. In this paper, we present the design of laboratory experiments that use a thermal source of x-rays to asymmetrically irradiate a low-density plastic foam sphere. The experiment will vary the density and hence the number of mean free paths of the sphere to study the radiation transport in different regimes. Finally, we have developed dimensionless parameters to relate the laboratory experiment to the astrophysical system and we show that we can perform the experiment in the same transport regime.« less

Designing experiments on thermal interactions by secondary-school students in a simulated laboratory environment

NASA Astrophysics Data System (ADS)

Lefkos, Ioannis; Psillos, Dimitris; Hatzikraniotis, Euripides

2011-07-01

Background and purpose: The aim of this study was to explore the effect of investigative activities with manipulations in a virtual laboratory on students' ability to design experiments. Sample Fourteen students in a lower secondary school in Greece attended a teaching sequence on thermal phenomena based on the use of information and communication technology, and specifically of the simulated virtual laboratory 'ThermoLab'. Design and methods A pre-post comparison was applied. Students' design of experiments was rated in eight dimensions; namely, hypothesis forming and verification, selection of variables, initial conditions, device settings, materials and devices used, process and phenomena description. A three-level ranking scheme was employed for the evaluation of students' answers in each dimension. Results A Wilcoxon signed-rank test revealed a statistically significant difference between the students' pre- and post-test scores. Additional analysis by comparing the pre- and post-test scores using the Hake gain showed high gains in all but one dimension, which suggests that this improvement was almost inclusive. Conclusions We consider that our findings support the statement that there was an improvement in students' ability to design experiments.

Enhancing Scientific Inquiry Literacy of Prospective Biology Teachers through Inquiry Lab Project in Microbiology

NASA Astrophysics Data System (ADS)

Kusnadi, K.; Rustaman, N. Y.; Redjeki, S.; Aryantha, I. N. P.

2017-09-01

The implementation of the inquiry laboratory based project to enhance scientific inquiry literacy of prospective biology teachers in Microbiology course has been done. The inquiry lab based project was designed by three stages were debriefing of basic microbiology lab skills, guided inquiry and free inquiry respectively. The Study was quasi experimental with control group pretest-posttest design. The subjects were prospective biology teachers consists of 80 students. The scientific inquiry literacy instrument refers to ScInqLiT by Wenning. The results showed that there was significant difference of scientific inquiry literacy posttest scores between experiment and control (α 0,05) and was obtained N-gain score was 0.49 (medium) to experiment and 0.24 (low) to control. Based on formative assessment showed that development of student’s scientific attitude, research and microbiology lab skills during conducting project were increased. Student’s research skills especially in identification of variables, constructing a hypothesis, communicating and concluding were increased. During implementation of inquiry project also showed that they carried out mind and hands-on and so collaborative group investigation lab activities. Our findings may aid in reforming higher-education, particularly in microbiology laboratory activities to better promote scientific inquiry literacy, scientific attitude, research and laboratory skills.

A Paperless Lab Manual - Lessons Learned

NASA Astrophysics Data System (ADS)

Hatten, Daniel L.; Hatten, Maggie W.

1999-10-01

Every freshman entering Rose-Hulman Institute of Technology is equipped with a laptop computer and a software package that allow classroom and laboratory instructors the freedom to make computer-based assignments, publish course materials in electronic form, etc. All introductory physics laboratories and many of our classrooms are networked, and students routinely take their laptop computers to class/lab. The introductory physics laboratory manual was converted to HTML in the summer of 1997 and was made available to students over the Internet vice printing a paper manual during the 1998-99 school year. The aim was to reduce paper costs and allow timely updates of the laboratory experiments. A poll conducted at the end of the school year showed a generally positive student response to the online laboratory manual, with some reservations.

Linking manipulative experiments to field data to test the dilution effect.

PubMed

Venesky, Matthew D; Liu, Xuan; Sauer, Erin L; Rohr, Jason R

2014-05-01

The dilution effect, the hypothesis that biodiversity reduces disease risk, has received support in many systems. However, few dilution effect studies have linked mechanistic experiments to field patterns to establish both causality and ecological relevance. We conducted a series of laboratory experiments and tested the dilution effect hypothesis in an amphibian-Batrachochytrium dendrobatidis (Bd) system and tested for consistency between our laboratory experiments and field patterns of amphibian species richness, host identity and Bd prevalence. In our laboratory experiments, we show that tadpoles can filter feed Bd zoospores and that the degree of suspension feeding was positively associated with their dilution potential. The obligate suspension feeder, Gastrophryne carolinensis, generally diluted the risk of chytridiomycosis for tadpoles of Bufo terrestris and Hyla cinerea, whereas tadpoles of B. terrestris (an obligate benthos feeder) generally amplified infections for the other species. In addition, G. carolinensis reduced Bd abundance on H. cinerea more so in the presence than absence of B. terrestris and B. terrestris amplified Bd abundance on H. cinerea more so in the absence than presence of G. carolinensis. Also, when ignoring species identity, species richness was a significant negative predictor of Bd abundance. In our analysis of field data, the presence of Bufo spp. and Gastrophryne spp. were significant positive and negative predictors of Bd prevalence, respectively, even after controlling for climate, vegetation, anthropogenic factors (human footprint), species richness and sampling effort. These patterns of dilution and amplification supported our laboratory findings, demonstrating that the results are likely ecologically relevant. The results from our laboratory and field data support the dilution effect hypothesis and also suggest that dilution and amplification are predictable based on host traits. Our study is among the first to link manipulative experiments, in which a potential dilution mechanism is supported, with analyses of field data on species richness, host identity, spatial autocorrelation and disease prevalence. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.

Experimental econophysics: Complexity, self-organization, and emergent properties

NASA Astrophysics Data System (ADS)

Huang, J. P.

2015-03-01

Experimental econophysics is concerned with statistical physics of humans in the laboratory, and it is based on controlled human experiments developed by physicists to study some problems related to economics or finance. It relies on controlled human experiments in the laboratory together with agent-based modeling (for computer simulations and/or analytical theory), with an attempt to reveal the general cause-effect relationship between specific conditions and emergent properties of real economic/financial markets (a kind of complex adaptive systems). Here I review the latest progress in the field, namely, stylized facts, herd behavior, contrarian behavior, spontaneous cooperation, partial information, and risk management. Also, I highlight the connections between such progress and other topics of traditional statistical physics. The main theme of the review is to show diverse emergent properties of the laboratory markets, originating from self-organization due to the nonlinear interactions among heterogeneous humans or agents (complexity).

Flexible attention deployment in threatening contexts: an instructed fear conditioning study.

PubMed

Shechner, Tomer; Pelc, Tatiana; Pine, Daniel S; Fox, Nathan A; Bar-Haim, Yair

2012-10-01

Factors leading humans to shift attention away from danger cues remain poorly understood. Two laboratory experiments reported here show that context interacts with learning experiences to shape attention avoidance of mild danger cues. The first experiment exposed 18 participants to contextual threat of electric shock. Attention allocation to mild danger cues was then assessed with the dot-probe task. Results showed that contextual threat caused subjects to avert attention from danger cues. In the second experiment, 36 participants were conditioned to the same contextual threat used in Experiment 1. These subjects then were randomly assigned to either an experimental group, trained to shift attention toward danger cues, or a placebo group exposed to the same stimuli without the training component. As in Experiment 1, contextual threat again caused attention allocation away from danger in the control group. However, this did not occur in the experimental group. These experiments show that acute contextual threat and learning experiences interact to shape the deployment of attention away from danger cues.

Brewing Science in the Chemistry Laboratory: A "Mashing" Investigation of Starch and Carbohydrates

ERIC Educational Resources Information Center

Pelter, Michael W.; McQuade, Jennifer

2005-01-01

The experiments that mimic the actual brewing process to explain the science to the nonscience majors is performed using malted barley as the source for both the starch and the amylase enzyme. The experiment introduces the concept of monitoring the progress of chemical reaction and was able to show the chemical breakdown of the starch to simple…

Can Robots Help the Learning of Skilled Actions?

PubMed Central

Reinkensmeyer, David J.; Patton, James L.

2010-01-01

Learning to move skillfully requires that the motor system adjusts muscle commands based on ongoing performance errors, a process influenced by the dynamics of the task being practiced. Recent experiments from our laboratories show how robotic devices can temporarily alter task dynamics in ways that contribute to the motor learning experience, suggesting possible applications in rehabilitation and sports training. PMID:19098524

Biology Notes.

ERIC Educational Resources Information Center

School Science Review, 1982

1982-01-01

Describes laboratory procedures, demonstrations, and classroom materials, including "diet poker" (nutrition game); an experiment on enzyme characteristics; demonstrations of yeast anaerobic respiration and color preference in Calliphora larvae; method to extract eugenol from clove oil to show antibiotic properties; and Benedict's test.…

Bright Days Ahead for Curiosity Mars Rover

NASA Image and Video Library

2011-03-18

This image shows preparation for March 2011 testing of the Mars Science Laboratory rover, Curiosity, in a space-simulation chamber; the rover will go through operational sequences in environmental conditions similar to what it will experience on Mars.

A Simple Experiment to Explore Standing Waves in a Flexible Corrugated Sound Tube

NASA Astrophysics Data System (ADS)

Amorim, Maria Eva; Sousa, Teresa Delmira; Carvalho, P. Simeão; Sousa, Adriano Sampaioe

2011-09-01

Sound tubes, pipes, and singing rods are used as musical instruments and as toys to perform amusing experiments. In particular, corrugated tubes present unique characteristics with respect to the sounds they can produce; that is why they have been studied so intensively, both at theoretical and experimental levels.1-4 Experimental studies usually involve expensive and sophisticated equipment that is out of reach of school laboratory facilities.3-6 In this paper we show how to investigate quantitatively the sounds produced by a flexible sound tube corrugated on the inside by using educational equipment readily available in school laboratories, such as the oscilloscope, the microphone, the anemometer, and the air pump. We show that it is possible for students to study the discontinuous spectrum of sounds produced by a flexible corrugated tube and go even further, computing the speed of sound in air with a simple experimental procedure.

Removal of antibiotics from piggery wastewater by biological aerated filter system: Treatment efficiency and biodegradation kinetics.

PubMed

Chen, Jun; Liu, You-Sheng; Zhang, Jin-Na; Yang, Yong-Qiang; Hu, Li-Xin; Yang, Yuan-Yuan; Zhao, Jian-Liang; Chen, Fan-Rong; Ying, Guang-Guo

2017-08-01

This study aimed to investigate the removal efficiency and mechanism for antibiotics in swine wastewater by a biological aerated filter system (BAF system) in combination with laboratory aerobic and anaerobic incubation experiments. Nine antibiotics including sulfamonomethoxine, sulfachloropyridazine, sulfamethazine, trimethoprim, norfloxacin, ofloxacin, lincomycin, leucomycin and oxytetracycline were detected in the wastewater with concentrations up to 192,000ng/L. The results from this pilot study showed efficient removals (>82%) of the conventional wastewater pollutants (BOD 5 , COD, TN and NH 3 -N) and the detected nine antibiotics by the BAF system. Laboratory simulation experiment showed first-order dissipation kinetics for the nine antibiotics in the wastewater under aerobic and anaerobic conditions. The biodegradation kinetic parameters successfully predicted the fate of the nine antibiotics in the BAF system. This suggests that biodegradation was the dominant process for antibiotic removal in the BAF system. Copyright © 2017 Elsevier Ltd. All rights reserved.

Inter-laboratory consistency and variability in the buccal micronucleus cytome assay depends on biomarker scored and laboratory experience: results from the HUMNxl international inter-laboratory scoring exercise.

PubMed

Bolognesi, Claudia; Knasmueller, Siegfried; Nersesyan, Armen; Roggieri, Paola; Ceppi, Marcello; Bruzzone, Marco; Blaszczyk, Ewa; Mielzynska-Svach, Danuta; Milic, Mirta; Bonassi, Stefano; Benedetti, Danieli; Da Silva, Juliana; Toledo, Raphael; Salvadori, Daisy Maria Fávero; Groot de Restrepo, Helena; Filipic, Metka; Hercog, Klara; Aktas, Ayça; Burgaz, Sema; Kundi, Michael; Grummt, Tamara; Thomas, Philip; Hor, Maryam; Escudero-Fung, Maria; Holland, Nina; Fenech, Michael

2017-03-01

The buccal micronucleus cytome (BMNcyt) assay in uncultured exfoliated epithelial cells from oral mucosa is widely applied in biomonitoring human exposures to genotoxic agents and is also proposed as a suitable test for prescreening and follow-up of precancerous oral lesions. The main limitation of the assay is the large variability observed in the baseline values of micronuclei (MNi) and other nuclear anomalies mainly related to different scoring criteria. The aim of this international collaborative study, involving laboratories with different level of experience, was to evaluate the inter- and intra-laboratory variations in the BMNcyt parameters, using recently implemented guidelines, in scoring cells from the same pooled samples obtained from healthy subjects (control group) and from cancer patients undergoing radiotherapy (treated group). The results indicate that all laboratories correctly discriminated samples from the two groups by a significant increase of micronucleus (MN) and nuclear bud (NBUD) frequencies and differentiated binucleated (BN) cells, associated with the exposure to ionizing radiation. The experience of the laboratories was shown to play an important role in the identification of the different cell types and nuclear anomalies. MN frequency in differentiated mononucleated (MONO) and BN cells showed the greatest consistency among the laboratories and low variability was also detected in the frequencies of MONO and BN cells. A larger variability was observed in classifying the different cell types, indicating the subjectivity in the interpretation of some of the scoring criteria while reproducibility of the results between scoring sessions was very good. An inter-laboratory calibration exercise is strongly recommended before starting studies with BMNcyt assay involving multiple research centers. © The Author 2016. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Reproducing stone monument photosynthetic-based colonization under laboratory conditions.

PubMed

Miller, Ana Zélia; Laiz, Leonila; Gonzalez, Juan Miguel; Dionísio, Amélia; Macedo, Maria Filomena; Saiz-Jimenez, Cesareo

2008-11-01

In order to understand the biodeterioration process occurring on stone monuments, we analyzed the microbial communities involved in these processes and studied their ability to colonize stones under controlled laboratory experiments. In this study, a natural green biofilm from a limestone monument was cultivated, inoculated on stone probes of the same lithotype and incubated in a laboratory chamber. This incubation system, which exposes stone samples to intermittently sprinkling water, allowed the development of photosynthetic biofilms similar to those occurring on stone monuments. Denaturing gradient gel electrophoresis (DGGE) analysis was used to evaluate the major microbial components of the laboratory biofilms. Cyanobacteria, green microalgae, bacteria and fungi were identified by DNA-based molecular analysis targeting the 16S and 18S ribosomal RNA genes. The natural green biofilm was mainly composed by the Chlorophyta Chlorella, Stichococcus, and Trebouxia, and by Cyanobacteria belonging to the genera Leptolyngbya and Pleurocapsa. A number of bacteria belonging to Alphaproteobacteria, Bacteroidetes and Verrucomicrobia were identified, as well as fungi from the Ascomycota. The laboratory colonization experiment on stone probes showed a colonization pattern similar to that occurring on stone monuments. The methodology described in this paper allowed to reproduce a colonization equivalent to the natural biodeteriorating process.

The chemistry teaching laboratory: The student perspective

NASA Astrophysics Data System (ADS)

Polles, John Steven

In this study, I investigated the Student/learner's experiences in the chemistry teaching laboratory and the meaning that she or he derived from these experiences. This study sought to answer these questions: (1) What was the students experience in the teaching laboratory?, (2) What aspects of the laboratory experience did the student value?, and (3) What beliefs did the student hold concerning the role of the laboratory experience in developing her or his understanding of chemistry? Students involved in an introductory chemistry course at Purdue University were asked to complete a two-part questionnaire consisting of 16 scaled response and 5 free response items, and 685 did so. Fourteen students also participated in a semi-structured individual interview. The questionnaire and interview were designed to probe the students' perceived experience and answer the above questions. I found that students possess strong conceptions of the laboratory experience: a pre-conception that colors their experience from the outset, and a post-conception that is a mix of positive and negative reflections. I also found that the learner deeply holds an implicit value in the laboratory experience. The other major finding was that the students' lived experience is dramatically shaped or influenced by external agencies, primarily the faculty (and by extension the teaching assistants). There is much debate in the extant literature over the learning value of the science teaching laboratory, but it is all from the perspective of faculty, curriculum designers, and administrators. This study adds the students' voice to the argument.

Sulphur tracer experiments in laboratory animals using 34S-labelled yeast.

PubMed

Martínez-Sierra, J Giner; Moreno Sanz, F; Herrero Espílez, P; Marchante Gayón, J M; Rodríguez Fernández, J; García Alonso, J I

2013-03-01

We have evaluated the use of (34)S-labelled yeast to perform sulphur metabolic tracer experiments in laboratory animals. The proof of principle work included the selection of the culture conditions for the preparation of sulphur labelled yeast, the study of the suitability of this labelled yeast as sulphur source for tracer studies using in vitro gastrointestinal digestion and the administration of the (34)S-labelled yeast to laboratory animals to follow the fate and distribution of (34)S in the organism. For in vitro gastrointestinal digestion, the combination of sodium dodecyl sulphate-polyacrylamide gel electrophoresis and high-performance liquid chromatography and inductively coupled plasma mass spectrometry (HPLC-ICP-MS) showed that labelled methionine, cysteine and other low molecular weight sulphur-containing biomolecules were the major components in the digested extracts of the labelled yeast. Next, in vivo kinetic experiments were performed in healthy Wistar rats after the oral administration of (34)S-labelled yeast. The isotopic composition of total sulphur in tissues, urine and faeces was measured by double-focusing inductively coupled plasma mass spectrometry after microwave digestion. It was observed that measurable isotopic enrichments were detected in all samples. Finally, initial investigations on sulphur isotopic composition of serum and urine samples by HPLC-ICP-MS have been carried out. For serum samples, no conclusive data were obtained. Interestingly, chromatographic analysis of urine samples showed differential isotope enrichment for several sulphur-containing biomolecules.

The Zombie Instability: Using Numerical Simulation to Design a Laboratory Experiment

NASA Astrophysics Data System (ADS)

Wang, Meng; Pei, Suyang; Jiang, Chung-Hsiang; Hassanzadeh, Pedram; Marcus, Philip

2014-11-01

A new type of finite amplitude-instability has been found in numerical simulations of stratified, rotating, shear flows. The instability occurs via baroclinic critical layers that create linearly unstable vortex layers, which roll-up into vortices. Under the right conditions, those vortices can form a new generation of vortices, resulting in ``vortex self-replication'' that fills the fluid with vortices. Creating this instability in a laboratory would provide further evidence for the existence of the instability, which we first found in numerical simulations of protoplanetary disks. To design a laboratory experiment we need to know how the flow parameters-- shear, rotation and stratification, etc. affect the instability. To build an experiment economically, we also need to know how the finite-amplitude trigger of the instability scales with viscosity and the size of the domain. In this talk, we summarize our findings. We present a map, in terms of the experimentally controllable parameters, that shows where the instability occurs and whether the instability creates a few isolated transient vortices, a few long-lived vortices, or long-lived, self-replicating vortices that fill the entire flow.

NIF laboratory astrophysics simulations investigating the effects of a radiative shock on hydrodynamic instabilities

NASA Astrophysics Data System (ADS)

Angulo, A. A.; Kuranz, C. C.; Drake, R. P.; Huntington, C. M.; Park, H.-S.; Remington, B. A.; Kalantar, D.; MacLaren, S.; Raman, K.; Miles, A.; Trantham, Matthew; Kline, J. L.; Flippo, K.; Doss, F. W.; Shvarts, D.

2016-10-01

This poster will describe simulations based on results from ongoing laboratory astrophysics experiments at the National Ignition Facility (NIF) relevant to the effects of radiative shock on hydrodynamically unstable surfaces. The experiments performed on NIF uniquely provide the necessary conditions required to emulate radiative shock that occurs in astrophysical systems. The core-collapse explosions of red supergiant stars is such an example wherein the interaction between the supernova ejecta and the circumstellar medium creates a region susceptible to Rayleigh-Taylor (R-T) instabilities. Radiative and nonradiative experiments were performed to show that R-T growth should be reduced by the effects of the radiative shocks that occur during this core-collapse. Simulations were performed using the radiation hydrodynamics code Hyades using the experimental conditions to find the mean interface acceleration of the instability and then further analyzed in the buoyancy drag model to observe how the material expansion contributes to the mix-layer growth. This work is funded by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas under Grant Number DE-FG52-09NA29548.

Heterosis Increases Fertility, Fecundity, and Survival of Laboratory-Produced F1 Hybrid Males of the Malaria Mosquito Anopheles coluzzii

PubMed Central

Ekechukwu, Nkiru E.; Baeshen, Rowida; Traorè, Sékou F.; Coulibaly, Mamadou; Diabate, Abdoulaye; Catteruccia, Flaminia; Tripet, Frédéric

2015-01-01

The success of vector control strategies aiming to decrease disease transmission via the release of sterile or genetically-modified male mosquitoes critically depends on mating between laboratory-reared males and wild females. Unfortunately, mosquito colonization, laboratory rearing, and genetic manipulations can all negatively affect male competitiveness. Heterosis is commonly used to produce domestic animals with enhanced vigor and homogenous genetic background and could therefore potentially improve the mating performance of mass-reared male mosquitoes. Here, we produced enhanced hybrid males of the malaria mosquito Anopheles coluzzii by crossing two strains colonized >35 and 8 years ago. We compared the amount of sperm and mating plug proteins they transferred to females, as well as their insemination rate, reproductive success and longevity under various experimental conditions. Across experiments, widespread adaptations to laboratory mating were detected in the older strain. In large-group mating experiments, no overall hybrid advantage in insemination rates and the amount of sperm and accessory gland proteins transferred to females was detected. Despite higher sperm activity, hybrid males did not appear more fecund. However, individual-male mating and laboratory-swarm experiments revealed that hybrid males, while inseminating fewer females than older inbred males, were significantly more fertile, producing larger mating plugs and drastically increasing female fecundity. Heterotic males also showed increased longevity. These results validate the use of heterosis for creating hybrid males with improved fitness from long-established inbred laboratory strains. Therefore, this simple approach could facilitate disease control strategies based on male mosquito releases with important ultimate benefits to human health. PMID:26497140

Miniature whirlwinds produced in the laboratory by high-voltage electrical discharges.

PubMed

Ryan, R T; Vonnegut, B

1970-06-12

Laboratory experiments showed that under certain conditions of vorticity the electrical heatinig produced by a high-voltage discharge at atmospheric pressure can cause the formation of a miniature tornado-like vortex. Once it forms, this vortex stabilizes the electrical discharge along its axis and changes its character from that of a spark to high-pressure variety of a glow discharge. Electrical and dynamic parameters were measured. By relating observations and measurements made in these experiments to previous work and to analogous situations in nature, it is concluded that the heating produced by electrical discharges in a large storm may play a significant role in forming and maintaining natural tornadoes.

Aerodynamic Evidence Pertaining to the Entry of Tektites into the Earth's Atmosphere

NASA Technical Reports Server (NTRS)

Chapman, Dean R.; Larson, Howard K.; Anderson, Lewis A.

1962-01-01

Evidence is presented which shows that the Australian and Java tektites entered the earth's atmosphere and experienced ablation by severe aerodynamic heating in hypervelocity flight. The laboratory experiments on hypervelocity ablation have reproduced ring-wave flow ridges and coiled circumferential flanges like those found on certain of these tektites. Systematic striae distortions exhibited in a thin layer beneath the front surface of australites also are reproduced in the laboratory ablation experiments, and are shown to correspond to the calculated distortions for aerodynamic ablation of a glass. About 98 percent of Australian tektites represent aerodynamically stable configurations during the ablative portion of an entry trajectory. Certain meteorites exhibit surface features similar to those on tektites.

Chemistry Graduate Teaching Assistants' Experiences in Academic Laboratories and Development of a Teaching Self-image

NASA Astrophysics Data System (ADS)

Gatlin, Todd Adam

Graduate teaching assistants (GTAs) play a prominent role in chemistry laboratory instruction at research based universities. They teach almost all undergraduate chemistry laboratory courses. However, their role in laboratory instruction has often been overlooked in educational research. Interest in chemistry GTAs has been placed on training and their perceived expectations, but less attention has been paid to their experiences or their potential benefits from teaching. This work was designed to investigate GTAs' experiences in and benefits from laboratory instructional environments. This dissertation includes three related studies on GTAs' experiences teaching in general chemistry laboratories. Qualitative methods were used for each study. First, phenomenological analysis was used to explore GTAs' experiences in an expository laboratory program. Post-teaching interviews were the primary data source. GTAs experiences were described in three dimensions: doing, knowing, and transferring. Gains available to GTAs revolved around general teaching skills. However, no gains specifically related to scientific development were found in this laboratory format. Case-study methods were used to explore and illustrate ways GTAs develop a GTA self-image---the way they see themselves as instructors. Two general chemistry laboratory programs that represent two very different instructional frameworks were chosen for the context of this study. The first program used a cooperative project-based approach. The second program used weekly, verification-type activities. End of the semester interviews were collected and served as the primary data source. A follow-up case study of a new cohort of GTAs in the cooperative problem-based laboratory was undertaken to investigate changes in GTAs' self-images over the course of one semester. Pre-semester and post-semester interviews served as the primary data source. Findings suggest that GTAs' construction of their self-image is shaped through the interaction of 1) prior experiences, 2) training, 3) beliefs about the nature of knowledge, 4) beliefs about the nature of laboratory work, and 5) involvement in the laboratory setting. Further GTAs' self-images are malleable and susceptible to change through their laboratory teaching experiences. Overall, this dissertation contributes to chemistry education by providing a model useful for exploring GTAs' development of a self-image in laboratory teaching. This work may assist laboratory instructors and coordinators in reconsidering, when applicable, GTA training and support. This work also holds considerable implications for how teaching experiences are conceptualized as part of the chemistry graduate education experience. Findings suggest that appropriate teaching experiences may contribute towards better preparing graduate students for their journey in becoming scientists.

Challenges in Implementing a Biorisk Management Program at Universitas Indonesia: A Checklist Tool for Biorisk Management.

PubMed

Naroeni, Aroem; Bachtiar, Endang Winiati; Ibrahim, Fera; Bela, Budiman; Kusminanti, Yuni; Pujiriani, Ike; Lestari, Fatma

Rapid development and advancement of bioresearch at a university's laboratories can have both positive and negative implications for public health and the environment. Many research activities in which biological materials have been created, modified, stored, and manipulated require safety procedures to keep the negative effects on humans and the environment as low as possible. The Occupational Health, Safety and Environmental (OHS&E) Department of the University of Indonesia (UI) is trying to increase the awareness and responsibility of its university members and laboratory staffs who work with biohazard materials by creating a biorisk checklist. The checklist was developed based on WHO guidelines and the National University of Singapore (NUS) Laboratory Manual, which contains 311 questions about the management, administration, and handling of various hazards, recombinant experiments, and animal and plant experiments. A gap analysis was run against the checklist in 14 laboratories at the University of Indonesia Salemba campus, which daily works with highly infectious pathogens and high-risk agents. Overall result showed that none of these laboratories had met all of the checklist items, and there were only 2 laboratories that had implemented more than half of the items. This checklist was proven to be a simple tool for assessing laboratories that handle and store biohazard materials, and it could be used as a monitoring tool for biorisk programs as well. It also could be further developed as a laboratory software application to increase its effectiveness and its accuracy.

Scaled laboratory experiments explain the kink behaviour of the Crab Nebula jet.

PubMed

Li, C K; Tzeferacos, P; Lamb, D; Gregori, G; Norreys, P A; Rosenberg, M J; Follett, R K; Froula, D H; Koenig, M; Seguin, F H; Frenje, J A; Rinderknecht, H G; Sio, H; Zylstra, A B; Petrasso, R D; Amendt, P A; Park, H S; Remington, B A; Ryutov, D D; Wilks, S C; Betti, R; Frank, A; Hu, S X; Sangster, T C; Hartigan, P; Drake, R P; Kuranz, C C; Lebedev, S V; Woolsey, N C

2016-10-07

The remarkable discovery by the Chandra X-ray observatory that the Crab nebula's jet periodically changes direction provides a challenge to our understanding of astrophysical jet dynamics. It has been suggested that this phenomenon may be the consequence of magnetic fields and magnetohydrodynamic instabilities, but experimental demonstration in a controlled laboratory environment has remained elusive. Here we report experiments that use high-power lasers to create a plasma jet that can be directly compared with the Crab jet through well-defined physical scaling laws. The jet generates its own embedded toroidal magnetic fields; as it moves, plasma instabilities result in multiple deflections of the propagation direction, mimicking the kink behaviour of the Crab jet. The experiment is modelled with three-dimensional numerical simulations that show exactly how the instability develops and results in changes of direction of the jet.

Redefining Authentic Research Experiences in Introductory Biology Laboratories and Barriers to Their Implementation

PubMed Central

Spell, Rachelle M.; Guinan, Judith A.; Miller, Kristen R.; Beck, Christopher W.

2014-01-01

Incorporating authentic research experiences in introductory biology laboratory classes would greatly expand the number of students exposed to the excitement of discovery and the rigor of the scientific process. However, the essential components of an authentic research experience and the barriers to their implementation in laboratory classes are poorly defined. To guide future reform efforts in this area, we conducted a national survey of biology faculty members to determine 1) their definitions of authentic research experiences in laboratory classes, 2) the extent of authentic research experiences currently experienced in their laboratory classes, and 3) the barriers that prevent incorporation of authentic research experiences into these classes. Strikingly, the definitions of authentic research experiences differ among faculty members and tend to emphasize either the scientific process or the discovery of previously unknown data. The low level of authentic research experiences in introductory biology labs suggests that more development and support is needed to increase undergraduate exposure to research experiences. Faculty members did not cite several barriers commonly assumed to impair pedagogical reform; however, their responses suggest that expanded support for development of research experiences in laboratory classes could address the most common barrier. PMID:24591509

Redefining authentic research experiences in introductory biology laboratories and barriers to their implementation.

PubMed

Spell, Rachelle M; Guinan, Judith A; Miller, Kristen R; Beck, Christopher W

2014-01-01

Incorporating authentic research experiences in introductory biology laboratory classes would greatly expand the number of students exposed to the excitement of discovery and the rigor of the scientific process. However, the essential components of an authentic research experience and the barriers to their implementation in laboratory classes are poorly defined. To guide future reform efforts in this area, we conducted a national survey of biology faculty members to determine 1) their definitions of authentic research experiences in laboratory classes, 2) the extent of authentic research experiences currently experienced in their laboratory classes, and 3) the barriers that prevent incorporation of authentic research experiences into these classes. Strikingly, the definitions of authentic research experiences differ among faculty members and tend to emphasize either the scientific process or the discovery of previously unknown data. The low level of authentic research experiences in introductory biology labs suggests that more development and support is needed to increase undergraduate exposure to research experiences. Faculty members did not cite several barriers commonly assumed to impair pedagogical reform; however, their responses suggest that expanded support for development of research experiences in laboratory classes could address the most common barrier.

Developing an online chemistry laboratory for non-chemistry majors

NASA Astrophysics Data System (ADS)

Poole, Jacqueline H.

Distance education, also known as online learning, is student-centered/self-directed educational opportunities. This style of learning is expanding in scope and is increasingly being accepted throughout the academic curriculum as a result of its flexibility for the student as well as the cost-effectiveness for the institution. Nevertheless, the introduction of online science courses including chemistry and physics have lagged behind due to the challenge of re-creation of the hands-on laboratory learning experience. This dissertation looks at the effectiveness of the design of a series of chemistry laboratory experiments for possible online delivery that provide students with simulated hands-on experiences. One class of college Chemistry 101 students conducted chemistry experiments inside and outside of the physical laboratory using instructions on Blackboard and Late Nite Labs(TM). Learning outcomes measured by (a) pretests, (b) written laboratory reports, (c) posttest assessments, (d) student reactions as determined by a questionnaire, and (e) a focus group interview were utilized to compare both types of laboratory experiences. The research findings indicated learning outcomes achieved by students outside of the traditional physical laboratory were statistically greater than the equivalent face-to-face instruction in the traditional laboratory. Evidence from student reactions comparing both types of laboratory formats (online and traditional face-to-face) indicated student preference for the online laboratory format. The results are an initial contribution to the design of a complete sequence of experiments that can be performed independently by online students outside of the traditional face-to-face laboratory that will satisfy the laboratory requirement for the two-semester college Chemistry 101 laboratory course.

Identification of crop cultivars with consistently high lignocellulosic sugar release requires the use of appropriate statistical design and modelling

PubMed Central

2013-01-01

Background In this study, a multi-parent population of barley cultivars was grown in the field for two consecutive years and then straw saccharification (sugar release by enzymes) was subsequently analysed in the laboratory to identify the cultivars with the highest consistent sugar yield. This experiment was used to assess the benefit of accounting for both the multi-phase and multi-environment aspects of large-scale phenotyping experiments with field-grown germplasm through sound statistical design and analysis. Results Complementary designs at both the field and laboratory phases of the experiment ensured that non-genetic sources of variation could be separated from the genetic variation of cultivars, which was the main target of the study. The field phase included biological replication and plot randomisation. The laboratory phase employed re-randomisation and technical replication of samples within a batch, with a subset of cultivars chosen as duplicates that were randomly allocated across batches. The resulting data was analysed using a linear mixed model that incorporated field and laboratory variation and a cultivar by trial interaction, and ensured that the cultivar means were more accurately represented than if the non-genetic variation was ignored. The heritability detected was more than doubled in each year of the trial by accounting for the non-genetic variation in the analysis, clearly showing the benefit of this design and approach. Conclusions The importance of accounting for both field and laboratory variation, as well as the cultivar by trial interaction, by fitting a single statistical model (multi-environment trial, MET, model), was evidenced by the changes in list of the top 40 cultivars showing the highest sugar yields. Failure to account for this interaction resulted in only eight cultivars that were consistently in the top 40 in different years. The correspondence between the rankings of cultivars was much higher at 25 in the MET model. This approach is suited to any multi-phase and multi-environment population-based genetic experiment. PMID:24359577

The Master level optics laboratory at the Institute of Optics

NASA Astrophysics Data System (ADS)

Adamson, Per

2017-08-01

The master level optics laboratory is a biannual, intensive laboratory course in the fields of geometrical, physical and modern optics. This course is intended for the master level student though Ph.D. advisors which often recommend it to their advisees. The students are required to complete five standard laboratory experiments and an independent project during a semester. The goals of the laboratory experiments are for the students to get hands-on experience setting up optical laboratory equipment, collecting and analyzing data, as well as to communicate key results. The experimental methods, analysis, and results of the standard experiments are submitted in a journal style report, while an oral presentation is given for the independent project.

Oceanic Whitecaps and Associated, Bubble-Mediated, Air-Sea Exchange Processes

DTIC Science & Technology

1992-10-01

experiments performed in laboratory conditions using Air-Sea Exchange Monitoring System (A-SEMS). EXPERIMENTAL SET-UP In a first look, the Air-Sea Exchange...Model 225, equipped with a Model 519 plug-in module. Other complementary information on A-SEMS along with results from first tests and calibration...between 9.50C and 22.40C within the first 24 hours after transferring the water sample into laboratory conditions. The results show an enhancement of

Reproductive fitness and dietary choice behavior of the genetic model organism Caenorhabditis elegans under semi-natural conditions.

PubMed

Freyth, Katharina; Janowitz, Tim; Nunes, Frank; Voss, Melanie; Heinick, Alexander; Bertaux, Joanne; Scheu, Stefan; Paul, Rüdiger J

2010-10-01

Laboratory breeding conditions of the model organism C. elegans do not correspond with the conditions in its natural soil habitat. To assess the consequences of the differences in environmental conditions, the effects of air composition, medium and bacterial food on reproductive fitness and/or dietary-choice behavior of C. elegans were investigated. The reproductive fitness of C. elegans was maximal under oxygen deficiency and not influenced by a high fractional share of carbon dioxide. In media approximating natural soil structure, reproductive fitness was much lower than in standard laboratory media. In seminatural media, the reproductive fitness of C. elegans was low with the standard laboratory food bacterium E. coli (γ-Proteobacteria), but significantly higher with C. arvensicola (Bacteroidetes) and B. tropica (β-Proteobacteria) as food. Dietary-choice experiments in semi-natural media revealed a low preference of C. elegans for E. coli but significantly higher preferences for C. arvensicola and B. tropica (among other bacteria). Dietary-choice experiments under quasi-natural conditions, which were feasible by fluorescence in situ hybridization (FISH) of bacteria, showed a high preference of C. elegans for Cytophaga-Flexibacter-Bacteroides, Firmicutes, and β-Proteobacteria, but a low preference for γ-Proteobacteria. The results show that data on C. elegans under standard laboratory conditions have to be carefully interpreted with respect to their biological significance.

Development of Accessible Laboratory Experiments for Students with Visual Impairments

ERIC Educational Resources Information Center

Kroes, KC; Lefler, Daniel; Schmitt, Aaron; Supalo, Cary A.

2016-01-01

The hands-on laboratory experiments are frequently what spark students' interest in science. Students who are blind or have low vision (BLV) typically do not get the same experience while participating in hands-on activities due to accessibility. Over the course of approximately nine months, common chemistry laboratory experiments were adapted and…

Do-It-Yourself Experiments for the Instructional Laboratory

ERIC Educational Resources Information Center

Craig, Norman C.; Hill, Cortland S.

2012-01-01

A new design for experiments in the general chemistry laboratory incorporates a "do-it-yourself" component for students. In this design, students perform proven experiments to gain experience with techniques for about two-thirds of a laboratory session and then spend the last part in the do-it-yourself component, applying the techniques to an…

A teaching intervention for reading laboratory experiments in college-level introductory chemistry

NASA Astrophysics Data System (ADS)

Kirk, Maria Kristine

The purpose of this study was to determine the effects that a pre-laboratory guide, conceptualized as a "scientific story grammar," has on college chemistry students' learning when they read an introductory chemistry laboratory manual and perform the experiments in the chemistry laboratory. The participants (N = 56) were students enrolled in four existing general chemistry laboratory sections taught by two instructors at a women's liberal arts college. The pre-laboratory guide consisted of eight questions about the experiment, including the purpose, chemical species, variables, chemical method, procedure, and hypothesis. The effects of the intervention were compared with those of the traditional pre-laboratory assignment for the eight chemistry experiments. Measures included quizzes, tests, chemistry achievement test, science process skills test, laboratory reports, laboratory average, and semester grade. The covariates were mathematical aptitude and prior knowledge of chemistry and science processes, on which the groups differed significantly. The study captured students' perceptions of their experience in general chemistry through a survey and interviews with eight students. The only significant differences in the treatment group's performance were in some subscores on lecture items and laboratory items on the quizzes. An apparent induction period was noted, in that significant measures occurred in mid-semester. Voluntary study with the pre-laboratory guide by control students precluded significant differences on measures given later in the semester. The groups' responses to the survey were similar. Significant instructor effects on three survey items were corroborated by the interviews. The researcher's students were more positive about their pre-laboratory tasks, enjoyed the laboratory sessions more, and were more confident about doing chemistry experiments than the laboratory instructor's groups due to differences in scaffolding by the instructors.

Measuring meaningful learning in the undergraduate chemistry laboratory

NASA Astrophysics Data System (ADS)

Galloway, Kelli R.

The undergraduate chemistry laboratory has been an essential component in chemistry education for over a century. The literature includes reports on investigations of singular aspects laboratory learning and attempts to measure the efficacy of reformed laboratory curriculum as well as faculty goals for laboratory learning which found common goals among instructors for students to learn laboratory skills, techniques, experimental design, and to develop critical thinking skills. These findings are important for improving teaching and learning in the undergraduate chemistry laboratory, but research is needed to connect the faculty goals to student perceptions. This study was designed to explore students' ideas about learning in the undergraduate chemistry laboratory. Novak's Theory of Meaningful Learning was used as a guide for the data collection and analysis choices for this research. Novak's theory states that in order for meaningful learning to occur the cognitive, affective, and psychomotor domains must be integrated. The psychomotor domain is inherent in the chemistry laboratory, but the extent to which the cognitive and affective domains are integrated is unknown. For meaningful learning to occur in the laboratory, students must actively integrate both the cognitive domain and the affective domains into the "doing" of their laboratory work. The Meaningful Learning in the Laboratory Instrument (MLLI) was designed to measure students' cognitive and affective expectations and experiences within the context of conducting experiments in the undergraduate chemistry laboratory. Evidence for the validity and reliability of the data generated by the MLLI were collected from multiple quantitative studies: a one semester study at one university, a one semester study at 15 colleges and universities across the United States, and a longitudinal study where the MLLI was administered 6 times during two years of general and organic chemistry laboratory courses. Results from these studies revealed students' narrow cognitive expectations for learning that go largely unmet by their experiences and diverse affective expectations and experiences. Concurrently, a qualitative study was carried out to describe and characterize students' cognitive and affective experiences in the undergraduate chemistry laboratory. Students were video recorded while performing one of their regular laboratory experiments and then interviewed about their experiences. The students' descriptions of their learning experiences were characterized by their overreliance on following the experimental procedure correctly rather than developing process-oriented problem solving skills. Future research could use the MLLI to intentionally compare different types of laboratory curricula or environments.

Laboratory Experiment of Magnetic Reconnection between Merging Flux Tubes with Strong Guide FIeld

NASA Astrophysics Data System (ADS)

Inomoto, M.; Kamio, S.; Kuwahata, A.; Ono, Y.

2013-12-01

Magnetic reconnection governs variety of energy release events in the universe, such as solar flares, geomagnetic substorms, and sawtooth crash in laboratory nuclear fusion experiments. Differently from the classical steady reconnection models, non-steady behavior of magnetic reconnection is often observed. In solar flares, intermittent enhancement of HXR emission is observed synchronously with multiple ejection of plammoids [1]. In laboratory reconnection experiments, the existence of the guide field, that is perpendicular to the reconnection field, makes significant changes on reconnection process. Generally the guide field will slow down the reconnection rate due to the increased magnetic pressure inside the current sheet. It also brings about asymmetric structure of the separatrices or effective particle acceleration in collisionless conditions. We have conducted laboratory experiments to study the behavior of the guide-field magnetic reconnection using plasma merging technique (push reconnection). Under substantial guide field even larger than the reconnection field, the reconnection generally exhibits non-steady feature which involves intermittent detachment of X-point and reconnection current center[2]. Transient enhancement of reconnection rate is observed simultaneously with the X-point motion[3]. We found two distinct phenomena associated with the guide-field non-steady reconnection. The one is the temporal and localized He II emission from X-point region, suggesting the production of energetic electrons which could excite the He ions in the vicinity of the X-point. The other is the excitation of large-amplitude electromagnetic waves which have similar properties with kinetic Alfven waves, whose amplitude show positive correlation with the enhancement of the reconnection electric field[4]. Electron beam instability caused by the energetic electrons accelerated to more than twice of the electron thermal velocity could be a potential driver of the monochromatic magnetic fluctuations. In conclusion, the laboratory guide field reconnection experiments showed some unique features such as ejection of current sheet, localized enhancement of emission, and excitation of low frequency waves, suggesting intermittent fast reconnection mechanism with significant electron acceleration. [1] N. Nishizuka et al., Astrophysical J. 711, 1062 (2010). [2] Y. Ono et al., Phys. Plasmas 18, 111213 (2011). [3] M. Inomoto et al., Plasma and Fusion Res. 8, 2401112 (2013). [4] M. Inomoto et al., Phys. Plasmas 20, 061209 (2013).

The Effect of Guided-Inquiry Laboratory Experiments on Science Education Students' Chemistry Laboratory Attitudes, Anxiety and Achievement

ERIC Educational Resources Information Center

Ural, Evrim

2016-01-01

The study aims to search the effect of guided inquiry laboratory experiments on students' attitudes towards chemistry laboratory, chemistry laboratory anxiety and their academic achievement in the laboratory. The study has been carried out with 37 third-year, undergraduate science education students, as a part of their Science Education Laboratory…

Laboratory investigation of surface processes on airless bodies due to electrostatic dust mobilization

NASA Astrophysics Data System (ADS)

Wang, X.; Hood, N.; Schwan, J.; Hsu, H. W.; Horanyi, M.

2017-12-01

Electrostatic dust mobilization on the surfaces of airless bodies due to direct exposure to solar wind and solar ultraviolet (UV) radiation has been suggested from a number of unusual planetary observations and supported by our recent laboratory experiments. This electrostatic process may have a significant contribution in the evolution of these surfaces in addition to other surface processes, e.g., thermal fragmentation. The critical questions are how this process changes the surface physical characteristics and how efficient this process can be. We report new laboratory experiments that record dust activities as function of the incoming fluxes of photons or energetic electrons over a long exposure time under Earth gravity. Dust is observed to hop and move on the surface, causing the significant change in surface morphology and becoming smoother over time. Our results indicate that the dynamics of dust mobilization may be complicated by temporal charging effect as dust moves. Various sizes and types of dust are examined, showing large effects on dust mobilization. These laboratory data will help us to predict the electrostatic surface processes and estimate their timescales in space conditions.

International Space Station (ISS)

NASA Image and Video Library

1998-11-01

This photograph shows the U.S. Laboratory Module (also called Destiny) for the International Space Station (ISS), in the Space Station manufacturing facility at the Marshall Space Flight Center, being readied for shipment to the Kennedy Space Center. The U.S. Laboratory module is the centerpiece of the ISS, where science experiments will be performed in the near-zero gravity of space. The Destiny Module was launched aboard the Space Shuttle orbiter Atlantis (STS-67 mission) on February 7, 2001. The aluminum module is 8.5 meters (28 feet) long and 4.3 meters (14 feet) in diameter. The laboratory consists of three cylindrical sections and two endcones with hatches that will be mated to other station components. A 50.9-centimeter- (20-inch-) diameter window is located on one side of the center module segment. This pressurized module is designed to accommodate pressurized payloads. It has a capacity of 24 rack locations, and payload racks will occupy 13 locations especially designed to support experiments. The ISS is a multidisciplinary laboratory, technology test bed, and observatory that will provide unprecedented undertakings in scientific, technological, and international experimentation.

International Space Station (ISS)

NASA Image and Video Library

1997-11-26

This photograph shows the U.S. Laboratory Module (also called Destiny) for the International Space Station (ISS), under construction in the Space Station manufacturing facility at the Marshall Space Flight Center. The U.S. Laboratory module is the centerpiece of the ISS, where science experiments will be performed in the near-zero gravity of space. The Destiny Module was launched aboard the Space Shuttle orbiter Atlantis (STS-67 mission) on February 7, 2001. The aluminum module is 8.5 meters (28 feet) long and 4.3 meters (14 feet) in diameter. The laboratory consists of three cylindrical sections and two end cones with hatches that will be mated to other station components. A 50.9-centimeter- (20-inch-) diameter window is located on one side of the center module segment. This pressurized module is designed to accommodate pressurized payloads. It has a capacity of 24 rack locations, and payload racks will occupy 13 locations especially designed to support experiments. The ISS is a multidisciplinary laboratory, technology test bed, and observatory that will provide unprecedented undertakings in scientific, technological, and international experimentation.

A Transition from a Traditional to a Project-Like Physical Chemistry Laboratory via a Heterogeneous Catalysis Study.

ERIC Educational Resources Information Center

Goldwasser, M. R.; Leal, O.

1979-01-01

Outlines an approach for instruction in a physical chemistry laboratory which combines traditional and project-like experiments. An outline of laboratory experiments and examples of project-like experiments are included. (BT)

Estimation and uncertainty analysis of dose response in an inter-laboratory experiment

NASA Astrophysics Data System (ADS)

Toman, Blaza; Rösslein, Matthias; Elliott, John T.; Petersen, Elijah J.

2016-02-01

An inter-laboratory experiment for the evaluation of toxic effects of NH2-polystyrene nanoparticles on living human cancer cells was performed with five participating laboratories. Previously published results from nanocytoxicity assays are often contradictory, mostly due to challenges related to producing a reliable cytotoxicity assay protocol for use with nanomaterials. Specific challenges include reproducibility preparing nanoparticle dispersions, biological variability from testing living cell lines, and the potential for nano-related interference effects. In this experiment, such challenges were addressed by developing a detailed experimental protocol and using a specially designed 96-well plate layout which incorporated a range of control measurements to assess multiple factors such as nanomaterial interference, pipetting accuracy, cell seeding density, and instrument performance. Detailed data analysis of these control measurements showed that good control of the experiments was attained by all participants in most cases. The main measurement objective of the study was the estimation of a dose response relationship between concentration of the nanoparticles and metabolic activity of the living cells, under several experimental conditions. The dose curve estimation was achieved by imbedding a three parameter logistic curve in a three level Bayesian hierarchical model, accounting for uncertainty due to all known experimental conditions as well as between laboratory variability in a top-down manner. Computation was performed using Markov Chain Monte Carlo methods. The fit of the model was evaluated using Bayesian posterior predictive probabilities and found to be satisfactory.

Student involvement in learning: Collaboration in science for PreService elementary teachers

NASA Astrophysics Data System (ADS)

Roychoudhury, Anita; Roth, Wolff-Michael

1992-03-01

The present study provided insights regarding the interactions that take place in collaborative science laboratory and regarding the outcome of such interactions. Science laboratory experiences structured by teachers have been criticized for allowing very little, if any, meaningful learning. However, this study showed that even structured laboratory experiments can provide insightful experience for students when conducted in a group setting that demanded interactive participation from all its members. The findings of the present study underscored the synergistic and supportive nature of collaborative groups. Here, students patiently repeated explanations to support the meaning construction on the part of their slower peers and elaborated their own understanding in the process; groups negotiated the meaning of observations and the corresponding theoretical explanations; students developed and practiced a range of social skills necessary in today’s workplace; and off-task behavior was thwarted by the group members motivated to work toward understanding rather than simply generating answers for task completion. The current findings suggest an increased use of collaborative learning environments for the teaching of science to elementary education majors. Some teachers have already made use of such settings in their laboratory teaching. However, collaborative learning should not be limited to the laboratory only, but be extended to more traditionally structured classes. The effects of such a switch in activity structures, increased quality of peer interaction, mastery of subject matter content, and decreased anxiety levels could well lead to better attitudes toward science among preservice elementary school teachers and eventually among their own students.

Fire spread characteristics determined in the laboratory

Treesearch

Richard C. Rothermel; Hal E. Anderson

1966-01-01

Fuel beds of ponderosa pine needles and white pine needles were burned under controlled environmental conditions to determine the effects of fuel moisture and windspeed upon the rate of fire spread. Empirical formulas are presented to show the effect of these parameters. A discussion of rate of spread and some simple experiments show how fuel may be preheated before...

Emissions of PCDD and PCDF from combustion of forest fuels and sugarcane: a comparison between field measurements and simulations in a laboratory burn facility.

PubMed

Black, R R; Meyer, C P; Touati, A; Gullett, B K; Fiedler, H; Mueller, J F

2011-05-01

Release of PCDD and PCDF from biomass combustion such as forest and agricultural crop fires has been nominated as an important source for these chemicals despite minimal characterisation. Available emission factors that have been experimentally determined in laboratory and field experiments vary by several orders of magnitude from <0.5 μg TEQ (t fuel consumed)(-1) to >100 μg TEQ (t fuel consumed)(-1). The aim of this study was to evaluate the effect of experimental methods on the emission factor. A portable field sampler was used to measure PCDD/PCDF emissions from forest fires and the same fuel when burnt over a brick hearth to eliminate potential soil effects. A laboratory burn facility was used to sample emissions from the same fuels. There was very good agreement in emission factors to air (EF(Air)) for forest fuel (Duke Forest, NC) of 0.52 (range: 0.40-0.79), 0.59 (range: 0.18-1.2) and 0.75 (range: 0.27-1.2) μg TEQ(WHO2005) (t fuel consumed)(-1) for the in-field, over a brick hearth, and burn facility experiments, respectively. Similarly, experiments with sugarcane showed very good agreement with EF(Air) of 1.1 (range: 0.40-2.2), 1.5 (range: 0.84-2.2) and 1.7 (range: 0.34-4.4) μg TEQ (t fuel consumed)(-1) for in-field, over a brick hearth, open field and burn facility experiments respectively. Field sampling and laboratory simulations were in good agreement, and no significant changes in emissions of PCDD/PCDF could be attributed to fuel storage and transport to laboratory test facilities. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Determination of the pH of Standard Buffer Solution: A Laboratory Experiment.

ERIC Educational Resources Information Center

Harris, K. R.

1985-01-01

Describes an experiment which shows: (1) how measurements of the reaction electromotive force for the cell (Pt/glass/NaCl(aq,m),buffer/AgCl/Ag/Pt) can be utilized in determining the absolute pH of the buffer; and (2) the demonstration of the use of the Debye-Huckel model of an electrolyte solution in solving an important electrochemical problem.…

Entrainment in Laboratory Simulations of Cumulus Cloud Flows

NASA Astrophysics Data System (ADS)

Narasimha, R.; Diwan, S.; Subrahmanyam, D.; Sreenivas, K. R.; Bhat, G. S.

2010-12-01

A variety of cumulus cloud flows, including congestus (both shallow bubble and tall tower types), mediocris and fractus have been generated in a water tank by simulating the release of latent heat in real clouds. The simulation is achieved through ohmic heating, injected volumetrically into the flow by applying suitable voltages between diametral cross-sections of starting jets and plumes of electrically conducting fluid (acidified water). Dynamical similarity between atmospheric and laboratory cloud flows is achieved by duplicating values of an appropriate non-dimensional heat release number. Velocity measurements, made by laser instrumentation, show that the Taylor entrainment coefficient generally increases just above the level of commencement of heat injection (corresponding to condensation level in the real cloud). Subsequently the coefficient reaches a maximum before declining to the very low values that characterize tall cumulus towers. The experiments also simulate the protected core of real clouds. Cumulus Congestus : Atmospheric cloud (left), simulated laboratory cloud (right). Panels below show respectively total heat injected and vertical profile of heating in the laboratory cloud.

The erosion of carbonate stone by acid rain: Laboratory and field investigations

USGS Publications Warehouse

Baedecker, P.A.; Reddy, M.M.

1993-01-01

One of the goals of research on the effects of acidic deposition on carbonate stone surfaces is to define the incremental impact of acidic deposition relative to natural weathering processes on the rate of carbonate stone erosion. If rain that impacts carbonate stone surfaces is resident on the surface long enough to approach chemical equilibrium, the incremental effect of hydrogen ion is expected to be small (i.e., 6% for a rain of pH 4.0). Under nonequilibrium (i.e., high flow rate) conditions, kinetic considerations suggest that the incremental effect of hydrogen ion deposition could be quite significant. Field run-off experiments involving the chemical analysis of rain collected from inclined stone slabs have been used to evaluate stone dissolution processes under ambient conditions of wet and dry deposition of acidic species. The stoichiometry of the reaction of stone with hydrogen ion is difficult to define from the field data due to scatter in the data attributed to hydrodynamic effects. Laboratory run-off experiments show that the stoichiometry is best defined by a reaction with H+ in which CO2 is released from the system. The baseline effect caused by water in equilibrium with atmospheric CO2 is identical in the field and in laboratory simulation. The experiments show that the solutions are close enough to equilibrium for the incremental effect of hydrogen ion to be minor (i.e., 24% for marble for a rain of pH 4.0) relative to dissolution due to water and carbonic acid reactions. Stone erosion rates based on physical measurement are approximately double the recession rates that are due to dissolution (estimated from the observed calcium content of the run-off solutions). The difference may reflect the loss of granular material not included in recession estimates based on the run-off data. Neither the field nor the laboratory run-off experiments indicate a pH dependence for the grain-removal process.

Observations of the Kaiser effect under multiaxial stress states: Implications for its use in determining in situ stress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holcomb, D.J.

1993-10-08

Experimental tests of the Kaiser effect, the stress-history dependence of acoustic emission production, show that interactions between principal stresses cannot be ignored as is commonly done when trying to use the Kaiser effect to determine in situ stress. Experimental results obtained under multiaxial stress states are explained in terms of a qualitative model. The results show that the commonly-used technique of loading uniaxially along various directions to determine stress history must be reevaluated as it cannot be justified in terms of the laboratory experiments. One possible resolution of the conflict between laboratory and field results is that the Kaiser effectmore » phenomenon observed in cores retrieved from the earth is not the same phenomenon as is observed in rock loaded under laboratory conditions.« less

75 FR 15675 - Professional Research Experience Program in Chemical Science and Technology Laboratory...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-30

... in physics, chemistry, mathematics, computer science, or engineering. Institutions should have a 4..., mathematics, computer science, or engineering with work experiences in laboratories or other settings...-0141-01] Professional Research Experience Program in Chemical Science and Technology Laboratory...

Plasma MRI Experiments at UW-Madison

NASA Astrophysics Data System (ADS)

Flanagan, K.; Clark, M.; Desangles, V.; Siller, R.; Wallace, J.; Weisberg, D.; Forest, C. B.

2015-11-01

Experiments for driving Keplerian-like flow profiles on both the Plasma Couette Experiment Upgrade (PCX-U) and the Wisconsin Plasma Astrophysics Laboratory (WiPAL) user facility are described. Instead of driving flow at the boundaries, as is typical in many liquid metal Couette experiments, a global drive is implemented. A large radial current is drawn across a small axial field generating torque across the whole profile. This global electrically driven flow is capable of producing profiles similar to Keplerian flow. PCX-U has been purposely constructed for MRI experiments, while similar experiments on the WiPAL device show the versatility of the user facility and provide a larger plasma volume. Numerical calculations show the predicted parameter spaces for exciting the MRI in these plasmas and the equilibrium flow profiles expected. In both devices, relevant MRI parameters appear to be within reach of typical operating characteristics.

Reprint: Good laboratory practice: preventing introduction of bias at the bench

PubMed Central

Macleod, Malcolm R; Fisher, Marc; O’Collins, Victoria; Sena, Emily S; Dirnagl, Ulrich; Bath, Philip MW; Buchan, Alistair; van der Worp, H Bart; Traystman, Richard J; Minematsu, Kazuo; Donnan, Geoffrey A; Howells, David W

2009-01-01

As a research community, we have failed to show that drugs, which show substantial efficacy in animal models of cerebral ischemia, can also improve outcome in human stroke. Accumulating evidence suggests this may be due, at least in part, to problems in the design, conduct, and reporting of animal experiments which create a systematic bias resulting in the overstatement of neuroprotective efficacy. Here, we set out a series of measures to reduce bias in the design, conduct and reporting of animal experiments modeling human stroke. PMID:18797473

ENHANCED BIODEGRADATION OF IOPROMIDE AND TRIMETHOPRIM IN NITRIFYING ACTIVATED SLUDGE

EPA Science Inventory

Iopromide and trimethoprim are frequently detected pharmaceuticals in effluents of wastewater treatment plants and in surface waters due to their persistence and high usage. Laboratory scale experiments showed that a significantly higher removal rate in nutrifying activated sludg...

Preparing for Solar and Thermal Testing of Curiosity Mars Rover

NASA Image and Video Library

2011-03-18

This image shows preparation for March 2011 testing of the Mars Science Laboratory rover, Curiosity, in a space-simulation chamber; the rover will go through operational sequences in environmental conditions similar to what it will experience on Mars.

Multidimensional Screening as a Pharmacology Laboratory Experience.

ERIC Educational Resources Information Center

Malone, Marvin H.; And Others

1979-01-01

A multidimensional pharmacodynamic screening experiment that addresses drug interaction is included in the pharmacology-toxicology laboratory experience of pharmacy students at the University of the Pacific. The student handout with directions for the procedure is reproduced, drug compounds tested are listed, and laboratory evaluation results are…

Scaled laboratory experiments explain the kink behaviour of the Crab Nebula jet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, C. K.; Tzeferacos, P.; Lamb, D.

X-ray images from the Chandra X-ray Observatory show that the South-East jet in the Crab nebula changes direction every few years. This remarkable phenomenon is also observed in jets associated with pulsar wind nebulae and other astrophysical objects, and therefore is a fundamental feature of astrophysical jet evolution that needs to be understood. Theoretical modeling and numerical simulations have suggested that this phenomenon may be a consequence of magnetic fields (B) and current-driven magnetohydrodynamic (MHD) instabilities taking place in the jet, but until now there has been no verification of this process in a controlled laboratory environment. Here we reportmore » the first such experiments, using scaled laboratory plasma jets generated by high-power lasers to model the Crab jet and monoenergetic-proton radiography to provide direct visualization and measurement of magnetic fields and their behavior. The toroidal magnetic field embedded in the supersonic jet triggered plasma instabilities and resulted in considerable deflections throughout the jet propagation, mimicking the kinks in the Crab jet. We also demonstrated that these kinks are stabilized by high jet velocity, consistent with the observation that instabilities alter the jet orientation but do not disrupt the overall jet structure. We successfully modeled these laboratory experiments with a validated three-dimensional (3D) numerical simulation, which in conjunction with the experiments provide compelling evidence that we have an accurate model of the most important physics of magnetic fields and MHD instabilities in the observed, kinked jet in the Crab nebula. The experiments initiate a novel approach in the laboratory for visualizing fields and instabilities associated with jets observed in various astrophysical objects, ranging from stellar to extragalactic systems. We expect that future work along this line will have important impact on the study and understanding of such fundamental astrophysical phenomena.« less

Scaled laboratory experiments explain the kink behaviour of the Crab Nebula jet

DOE PAGES

Li, C. K.; Tzeferacos, P.; Lamb, D.; ...

2016-10-07

X-ray images from the Chandra X-ray Observatory show that the South-East jet in the Crab nebula changes direction every few years. This remarkable phenomenon is also observed in jets associated with pulsar wind nebulae and other astrophysical objects, and therefore is a fundamental feature of astrophysical jet evolution that needs to be understood. Theoretical modeling and numerical simulations have suggested that this phenomenon may be a consequence of magnetic fields (B) and current-driven magnetohydrodynamic (MHD) instabilities taking place in the jet, but until now there has been no verification of this process in a controlled laboratory environment. Here we reportmore » the first such experiments, using scaled laboratory plasma jets generated by high-power lasers to model the Crab jet and monoenergetic-proton radiography to provide direct visualization and measurement of magnetic fields and their behavior. The toroidal magnetic field embedded in the supersonic jet triggered plasma instabilities and resulted in considerable deflections throughout the jet propagation, mimicking the kinks in the Crab jet. We also demonstrated that these kinks are stabilized by high jet velocity, consistent with the observation that instabilities alter the jet orientation but do not disrupt the overall jet structure. We successfully modeled these laboratory experiments with a validated three-dimensional (3D) numerical simulation, which in conjunction with the experiments provide compelling evidence that we have an accurate model of the most important physics of magnetic fields and MHD instabilities in the observed, kinked jet in the Crab nebula. The experiments initiate a novel approach in the laboratory for visualizing fields and instabilities associated with jets observed in various astrophysical objects, ranging from stellar to extragalactic systems. We expect that future work along this line will have important impact on the study and understanding of such fundamental astrophysical phenomena.« less

Correlation, necessity, and sufficiency: Common errors in the scientific reasoning of undergraduate students for interpreting experiments.

PubMed

Coleman, Aaron B; Lam, Diane P; Soowal, Lara N

2015-01-01

Gaining an understanding of how science works is central to an undergraduate education in biology and biochemistry. The reasoning required to design or interpret experiments that ask specific questions does not come naturally, and is an essential part of the science process skills that must be learned for an understanding of how scientists conduct research. Gaps in these reasoning skills make it difficult for students to become proficient in reading primary scientific literature. In this study, we assessed the ability of students in an upper-division biochemistry laboratory class to use the concepts of correlation, necessity, and sufficiency in interpreting experiments presented in a format and context that is similar to what they would encounter when reading a journal article. The students were assessed before and after completion of a laboratory module where necessary vs. sufficient reasoning was used to design and interpret experiments. The assessment identified two types of errors that were commonly committed by students when interpreting experimental data. When presented with an experiment that only establishes a correlation between a potential intermediate and a known effect, students frequently interpreted the intermediate as being sufficient (causative) for the effect. Also, when presented with an experiment that tests only necessity for an intermediate, they frequently made unsupported conclusions about sufficiency, and vice versa. Completion of the laboratory module and instruction in necessary vs. sufficient reasoning showed some promise for addressing these common errors. © 2015 The International Union of Biochemistry and Molecular Biology.

Optical and TEM study of shock metamorphism from the Sedan test site

NASA Technical Reports Server (NTRS)

Gratz, A. J.

1992-01-01

Thus far, detailed petrologic studies of shock metamorphism have been performed on samples recovered from laboratory experiments and on a few natural impactites. The loading history of these samples is quite different: In particular, laboratory experiments spend only a short time (less than 1 microsec) at peak pressure, whereas natural impactites may have stress pulses from 0.1 - 1 ms. On the other hand, laboratory experiments have known stress histories; natural impactites do not. Natural samples are also subjected to thousands or millions of years of postshock annealing and/or weathering. A useful intermediate case is that of nuclear detonation. Stress pulses for these events can reach 0.1 ms or higher, and samples are obtained in pristine condition. All three types of loading produce stresses of hundreds of kilobars. Samples studied were taken from the Sedan nulcear test site, and consist of a coarse-grained granodiorite containing quartz, K-feldspar, cordierite, and hornblende. Samples were studied optically in this section, then were thinned with an ion mill and studied by transmission electron microscopy (TEM). Optically, quartz and K-feldspar displayed numerous sets of planar deformation features (PDF's) identical to the nondecorated PDF's seen in laboratory samples and many natural impactites. TEM study showed that the PDF's in quartz and feldspar corresponded to densely packed wide transformation lamellae identical to those described in laboratory studies. The transformation lamellae in both minerals were amorphous, with no sign of high-pressure phases. In the case of K-feldspar only, narrow sublamellae extended outward from some wide lamellae. Quartz, which was more abundant and studied more extensively, contained no shock-induced dislocations. Some planar features were also seen in cordierite, but could not be identified due to rapid beam damage. No shock defects were seen in hornblende in TEM. The shock-induced defects present at the Sedan site are very similar to those seen in shock recovery experiments, and also to those present at certain natural events (e.g., Meteor Crater). This suggests that shock deformation in quartz is not strongly dependent on shock pulse duration, and that laboratory recovery experiments are useful simulations of natural impact events.

Estimating Fault Friction From Seismic Signals in the Laboratory

DOE PAGES

Rouet-Leduc, Bertrand; Hulbert, Claudia; Bolton, David C.; ...

2018-01-29

Nearly all aspects of earthquake rupture are controlled by the friction along the fault that progressively increases with tectonic forcing but in general cannot be directly measured. We show that fault friction can be determined at any time, from the continuous seismic signal. In a classic laboratory experiment of repeating earthquakes, we find that the seismic signal follows a specific pattern with respect to fault friction, allowing us to determine the fault's position within its failure cycle. Using machine learning, we show that instantaneous statistical characteristics of the seismic signal are a fingerprint of the fault zone shear stress andmore » frictional state. Further analysis of this fingerprint leads to a simple equation of state quantitatively relating the seismic signal power and the friction on the fault. Finally, these results show that fault zone frictional characteristics and the state of stress in the surroundings of the fault can be inferred from seismic waves, at least in the laboratory.« less

Estimating Fault Friction From Seismic Signals in the Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rouet-Leduc, Bertrand; Hulbert, Claudia; Bolton, David C.

Nearly all aspects of earthquake rupture are controlled by the friction along the fault that progressively increases with tectonic forcing but in general cannot be directly measured. We show that fault friction can be determined at any time, from the continuous seismic signal. In a classic laboratory experiment of repeating earthquakes, we find that the seismic signal follows a specific pattern with respect to fault friction, allowing us to determine the fault's position within its failure cycle. Using machine learning, we show that instantaneous statistical characteristics of the seismic signal are a fingerprint of the fault zone shear stress andmore » frictional state. Further analysis of this fingerprint leads to a simple equation of state quantitatively relating the seismic signal power and the friction on the fault. Finally, these results show that fault zone frictional characteristics and the state of stress in the surroundings of the fault can be inferred from seismic waves, at least in the laboratory.« less

Effects of using structured templates for recalling chemistry experiments.

PubMed

Willoughby, Cerys; Logothetis, Thomas A; Frey, Jeremy G

2016-01-01

The way that we recall information is dependent upon both the knowledge in our memories and the conditions under which we recall the information. Electronic Laboratory Notebooks can provide a structured interface for the capture of experiment records through the use of forms and templates. These templates can be useful by providing cues to help researchers to remember to record particular aspects of their experiment, but they may also constrain the information that is recorded by encouraging them to record only what is asked for. It is therefore unknown whether using structured templates for capturing experiment records will have positive or negative effects on the quality and usefulness of the records for assessment and future use. In this paper we report on the results of a set of studies investigating the effects of different template designs on the recording of experiments by undergraduate students and academic researchers. The results indicate that using structured templates to write up experiments does make a significant difference to the information that is recalled and recorded. These differences have both positive and negative effects, with templates prompting the capture of specific information that is otherwise forgotten, but also apparently losing some of the personal elements of the experiment experience such as observations and explanations. Other unexpected effects were seen with templates that can change the information that is captured, but also interfere with the way an experiment is conducted. Our results showed that using structured templates can improve the completeness of the experiment context information captured but can also cause a loss of personal elements of the experiment experience when compared with allowing the researcher to structure their own record. The results suggest that interfaces for recording information about chemistry experiments, whether paper-based questionnaires or templates in Electronic Laboratory Notebooks, can be an effective way to improve the quality of experiment write-ups, but that care needs to be taken to ensure that the correct cues are provided.Graphical abstractScientists have traditionally recorded their research in paper notebooks, a format that provides great flexibility for capturing information. In contrast, Electronic Laboratory Notebooks frequently make use of forms or structured templates for capturing experiment records. Structured templates can provide cues that can improve record quality by increasing the amount of information captured and encouraging consistency. However, using the wrong cues can lead to a loss of personal elements of the experiment experience and frustrate users. This image shows two participants from one of our studies recording their experiment using a computer-based template.

How do leaders promote cooperation? The effects of charisma and procedural fairness.

PubMed

De Cremer, David; van Knippenberg, Daan

2002-10-01

The present research examined the effect of leaders' procedural fairness and perceived charisma on an important organizational process: cooperation. Both charisma and procedural fairness were predicted to have a positive effect on cooperation, and procedural fairness and charisma were predicted to interact such that their effects are stronger alone than in conjunction. Results from a scenario experiment, a cross-sectional survey, and a laboratory experiment supported these predictions. Results from the laboratory study also showed that the interactive effect of leader charisma and procedural fairness on cooperation was mediated by their interactive effect on the sense of group belongingness. It is concluded that leader charisma and procedural fairness may engender cooperation because they appeal to relational concerns.

Experiments in advanced control concepts for space robotics - An overview of the Stanford Aerospace Robotics Laboratory

NASA Technical Reports Server (NTRS)

Hollars, M. G.; Cannon, R. H., Jr.; Alexander, H. L.; Morse, D. F.

1987-01-01

The Stanford University Aerospace Robotics Laboratory is actively developing and experimentally testing advanced robot control strategies for space robotic applications. Early experiments focused on control of very lightweight one-link manipulators and other flexible structures. The results are being extended to position and force control of mini-manipulators attached to flexible manipulators and multilink manipulators with flexible drive trains. Experimental results show that end-point sensing and careful dynamic modeling or adaptive control are key to the success of these control strategies. Free-flying space robot simulators that operate on an air cushion table have been built to test control strategies in which the dynamics of the base of the robot and the payload are important.

Experiment E89-044 of quasi-elastic diffusion 3He(e,e'p) at Jefferson Laboratory: Analyze cross sections of the two body breakup in parallel kinematics; Experience E89-044 de diffusion quasi-elastique 3he(e,e'p) au Jefferson Laboratory : analyse des sections efficaces de desintegration a deux corps en cinematique parallele (in French)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Penel-Nottaris, Emilie

2004-07-01

The Jefferson Lab Hall A experiment has measured the 3He(e,e'p) reaction cross sections. The separation of the longitudinal and transverse response functions for the two-body breakup reaction in parallel kinematics allows to study the bound proton electromagnetic properties in the 3He nucleus and the involved nuclear mechanisms beyond impulse approximation. Preliminary cross sections show some disagreement with theoretical predictions for the forward angles kinematics around 0 MeV/c missing momenta, and sensitivity to final state interactions and 3He wave functions for missing momenta of 300 MeV/c.

p-Aminophenol degradation by ozonation combined with sonolysis: operating conditions influence and mechanism.

PubMed

He, Zhiqiao; Song, Shuang; Ying, Haiping; Xu, Lejin; Chen, Jianmeng

2007-07-01

The degradation of p-aminophenol (PAP) in aqueous solution by sonolysis, by ozonation, and by a combination of both was investigated in laboratory-scale experiments. Operation parameters such as pH, temperature, ultrasonic energy density and ozone dose were optimized with regard to the efficiency of PAP removal. The concentration of PAP during the reaction was detected by high-pressure liquid chromatography. The concentrations of ammonium ions and nitrate ions were monitored during the degradation. Intermediate products such as 4-iminocyclohexa-2,5-dien-1-one, phenol, but-2-enedioic acid, and acetic acid were detected by gas chromatography coupled with mass spectrometry. The degradation rate of PAP was higher in the combined system than in the linear combination of separate experiments. The degradation efficiency was decreased rapidly when n-butanol was added to the combined reaction system, which showed that some radical reaction might proceed during the laboratory experiments.

Scaled laboratory experiments explain the kink behaviour of the Crab Nebula jet

PubMed Central

Li, C. K.; Tzeferacos, P.; Lamb, D.; Gregori, G.; Norreys, P. A.; Rosenberg, M. J.; Follett, R. K.; Froula, D. H.; Koenig, M.; Seguin, F. H.; Frenje, J. A.; Rinderknecht, H. G.; Sio, H.; Zylstra, A. B.; Petrasso, R. D.; Amendt, P. A.; Park, H. S.; Remington, B. A.; Ryutov, D. D.; Wilks, S. C.; Betti, R.; Frank, A.; Hu, S. X.; Sangster, T. C.; Hartigan, P.; Drake, R. P.; Kuranz, C. C.; Lebedev, S. V.; Woolsey, N. C.

2016-01-01

The remarkable discovery by the Chandra X-ray observatory that the Crab nebula's jet periodically changes direction provides a challenge to our understanding of astrophysical jet dynamics. It has been suggested that this phenomenon may be the consequence of magnetic fields and magnetohydrodynamic instabilities, but experimental demonstration in a controlled laboratory environment has remained elusive. Here we report experiments that use high-power lasers to create a plasma jet that can be directly compared with the Crab jet through well-defined physical scaling laws. The jet generates its own embedded toroidal magnetic fields; as it moves, plasma instabilities result in multiple deflections of the propagation direction, mimicking the kink behaviour of the Crab jet. The experiment is modelled with three-dimensional numerical simulations that show exactly how the instability develops and results in changes of direction of the jet. PMID:27713403

Remote sensing and laboratory techniques for monitoring ocean dumping

NASA Technical Reports Server (NTRS)

Ohlhorst, C. W.; Johnson, R. W.; Meyer, E. R.

1977-01-01

Results of field experiments conducted in the Atlantic Coastal Zone indicate that plumes resulting from ocean dumping of acid waste and sewage sludge have distinguishable spectral characteristics when the radiance of the pollutant is normalized (ratioed to) background ocean water. Acid waste spectra peak between 550-650 nm while sewage sludge spectra have peak values at wavelengths of about 700 nm or greater. Results indicate that identification of acid waste and sewage sludge plumes may be independent of geographical location in the Atlantic Coastal Zone. Radiance ratio curves obtained in the laboratory qualitatively agree with those obtained from field experiments. Results from the July 25, 1977, Galveston Deep Ocean Dump Site experiment show the radiance ratio curve of the biodigested industrial waste to be fairly flat and similar to the radiance ratio curves of sewage sludge line dumps and sewage sludge spot dumps that have been in the water for several hours.

Role of a quality management system in improving patient safety - laboratory aspects.

PubMed

Allen, Lynn C

2013-09-01

The aim of this study is to describe how implementation of a quality management system (QMS) based on ISO 15189 enhances patient safety. A literature review showed that several European hospitals implemented a QMS based on ISO 9001 and assessed the impact on patient safety. An Internet search showed that problems affecting patient safety have occurred in a number of laboratories across Canada. The requirements of a QMS based on ISO 15189 are outlined, and the impact of the implementation of each requirement on patient safety is summarized. The Quality Management Program - Laboratory Services in Ontario is briefly described, and the experience of Ontario laboratories with Ontario Laboratory Accreditation, based on ISO 15189, is outlined. Several hospitals that implemented ISO 9001 reported either a positive impact or no impact on patient safety. Patient safety problems in Canadian laboratories are described. Implementation of each requirement of the QMS can be seen to have a positive effect on patient safety. Average laboratory conformance on Ontario Laboratory Accreditation is very high, and laboratories must address and resolve any nonconformities. Other standards, practices, and quality requirements may also contribute to patient safety. Implementation of a QMS based on ISO 15189 provides a solid foundation for quality in the laboratory and enhances patient safety. It helps to prevent patient safety issues; when such issues do occur, effective processes are in place for investigation and resolution. Patient safety problems in Canadian laboratories might have been prevented had effective QMSs been in place. Ontario Laboratory Accreditation has had a positive impact on quality in Ontario laboratories. Copyright © 2013 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Comparison in Schemes for Simulating Depositional Growth of Ice Crystal between Theoretical and Laboratory Data

NASA Astrophysics Data System (ADS)

Zhai, Guoqing; Li, Xiaofan

2015-04-01

The Bergeron-Findeisen process has been simulated using the parameterization scheme for the depositional growth of ice crystal with the temperature-dependent theoretically predicted parameters in the past decades. Recently, Westbrook and Heymsfield (2011) calculated these parameters using the laboratory data from Takahashi and Fukuta (1988) and Takahashi et al. (1991) and found significant differences between the two parameter sets. There are two schemes that parameterize the depositional growth of ice crystal: Hsie et al. (1980), Krueger et al. (1995) and Zeng et al. (2008). In this study, we conducted three pairs of sensitivity experiments using three parameterization schemes and the two parameter sets. The pre-summer torrential rainfall event is chosen as the simulated rainfall case in this study. The analysis of root-mean-squared difference and correlation coefficient between the simulation and observation of surface rain rate shows that the experiment with the Krueger scheme and the Takahashi laboratory-derived parameters produces the best rain-rate simulation. The mean simulated rain rates are higher than the mean observational rain rate. The calculations of 5-day and model domain mean rain rates reveal that the three schemes with Takahashi laboratory-derived parameters tend to reduce the mean rain rate. The Krueger scheme together with the Takahashi laboratory-derived parameters generate the closest mean rain rate to the mean observational rain rate. The decrease in the mean rain rate caused by the Takahashi laboratory-derived parameters in the experiment with the Krueger scheme is associated with the reductions in the mean net condensation and the mean hydrometeor loss. These reductions correspond to the suppressed mean infrared radiative cooling due to the enhanced cloud ice and snow in the upper troposphere.

Reference earth orbital research and applications investigations (blue book). Volume 3: Physics

NASA Technical Reports Server (NTRS)

1971-01-01

The definition of physics experiments to be conducted aboard the space station is presented. The four functional program elements are: (1) space physics research laboratory, (2) plasma physics and environmental perturbation laboratory, (3) cosmic ray physics laboratory, and (4) physics and chemistry laboratory. The experiments to be conducted by each facility are defined and the crew member requirements to accomplish the experiments are presented.

Cardiac Muscle Studies with Rat Ventricular Strips

ERIC Educational Resources Information Center

Whitten, Bert K.; Faleschini, Richard J.

1977-01-01

Details undergraduate physiology laboratory experiments that demonstrate mechanical properties of cardiac muscle, using strips from the ventricle of a rat heart. Includes procedures for obtaining length-tension curves, demonstrating the role of calcium in excitation-contraction coupling, and showing effects of several cardiovascular drugs…

Spreadsheets Answer "What If...?

ERIC Educational Resources Information Center

Pogge, Alfred F.; Lunetta, Vincent N.

1987-01-01

Demonstrates how a spreadsheet program can do calculations, freeing students to question, analyze data and learn science. Notes several popular spreadsheet programs. Gives an example using Lotus 1-2-3 spreadsheets for a sampling experiment in Biology. Shows other examples of spreadsheet use in laboratory activities. (CW)

ASSESSMENT OF SULFATE REDUCTION RATES IN LABORATORY EXPERIMENTS

EPA Science Inventory

Two successful field demonstrations of sulfate reducing bacteria (SRB) bioreactors showed needs for research: 1) improve the understanding of the processes in the bioreactor and its longetivity and 2) improve and quantify the design of the bioreactors. An important component of t...

A Two-Week Guided Inquiry Protein Separation and Detection Experiment for Undergraduate Biochemistry

ERIC Educational Resources Information Center

Carolan, James P.; Nolta, Kathleen V.

2016-01-01

A laboratory experiment for teaching protein separation and detection in an undergraduate biochemistry laboratory course is described. This experiment, performed in two, 4 h laboratory periods, incorporates guided inquiry principles to introduce students to the concepts behind and difficulties of protein purification. After using size-exclusion…

Simulated and Virtual Science Laboratory Experiments: Improving Critical Thinking and Higher-Order Learning Skills

ERIC Educational Resources Information Center

Simon, Nicole A.

2013-01-01

Virtual laboratory experiments using interactive computer simulations are not being employed as viable alternatives to laboratory science curriculum at extensive enough rates within higher education. Rote traditional lab experiments are currently the norm and are not addressing inquiry, Critical Thinking, and cognition throughout the laboratory…

Wiki Laboratory Notebooks: Supporting Student Learning in Collaborative Inquiry-Based Laboratory Experiments

ERIC Educational Resources Information Center

Lawrie, Gwendolyn Angela; Grøndahl, Lisbeth; Boman, Simon; Andrews, Trish

2016-01-01

Recent examples of high-impact teaching practices in the undergraduate chemistry laboratory that include course-based undergraduate research experiences and inquiry-based experiments require new approaches to assessing individual student learning outcomes. Instructors require tools and strategies that can provide them with insight into individual…

Green Fluorescent Protein-Focused Bioinformatics Laboratory Experiment Suitable for Undergraduates in Biochemistry Courses

ERIC Educational Resources Information Center

Rowe, Laura

2017-01-01

An introductory bioinformatics laboratory experiment focused on protein analysis has been developed that is suitable for undergraduate students in introductory biochemistry courses. The laboratory experiment is designed to be potentially used as a "stand-alone" activity in which students are introduced to basic bioinformatics tools and…

An Example of a Laboratory Teaching Experience in a Professional Year (Plan B) Program

ERIC Educational Resources Information Center

Miller, P. J.; And Others

1978-01-01

A laboratory teaching experience (L.T.E.) was designed to focus on three teaching behaviors. It was recognized that a behavioral approach to teaching simplified its complexity by isolating specific teaching behaviors. Discusses the development and evaluation of the laboratory teaching experience. (Author/RK)

Capillary Electrophoresis Analysis of Cations in Water Samples: An Experiment for the Introductory Laboratory

ERIC Educational Resources Information Center

Pursell, Christopher J.; Chandler, Bert; Bushey, Michelle M.

2004-01-01

Capillary electrophoresis is gradually working its way into the undergraduate laboratory curriculum. Typically, experiments utilizing this newer technology have been introduced into analytical or instrumental courses. The authors of this article have introduced an experiment into the introductory laboratory that utilizes capillary electrophoresis…

An Undergraduate Laboratory Experiment in Bioinorganic Chemistry: Ligation States of Myoglobin

ERIC Educational Resources Information Center

Bailey, James A.

2011-01-01

Although there are numerous inorganic model systems that are readily presented as undergraduate laboratory experiments in bioinorganic chemistry, there are few examples that explore the inorganic chemistry of actual biological molecules. We present a laboratory experiment using the oxygen-binding protein myoglobin that can be easily incorporated…

Consumer-Oriented Laboratory Activities: A Manual for Secondary Science Students.

ERIC Educational Resources Information Center

Anderson, Jacqueline; McDuffie, Thomas E., Jr.

This document provides a laboratory manual for use by secondary level students in performing consumer-oriented laboratory experiments. Each experiment includes an introductory question outlining the purpose of the investigation, a detailed discussion, detailed procedures, questions to be answered upon completing the experiment, and information for…

Circular dichroism spectroscopy: Enhancing a traditional undergraduate biochemistry laboratory experience.

PubMed

Lewis, Russell L; Seal, Erin L; Lorts, Aimee R; Stewart, Amanda L

2017-11-01

The undergraduate biochemistry laboratory curriculum is designed to provide students with experience in protein isolation and purification protocols as well as various data analysis techniques, which enhance the biochemistry lecture course and give students a broad range of tools upon which to build in graduate level laboratories or once they begin their careers. One of the most common biochemistry protein purification experiments is the isolation and characterization of cytochrome c. Students across the country purify cytochrome c, lysozyme, or some other well-known protein to learn these common purification techniques. What this series of experiments lacks is the use of sophisticated instrumentation that is rarely available to undergraduate students. To give students a broader background in biochemical spectroscopy techniques, a new circular dichroism (CD) laboratory experiment was introduced into the biochemistry laboratory curriculum. This CD experiment provides students with a means of conceptualizing the secondary structure of their purified protein, and assessments indicate that students' understanding of the technique increased significantly. Students conducted this experiment with ease and in a short time frame, so this laboratory is conducive to merging with other data analysis techniques within a single laboratory period. © 2017 by The International Union of Biochemistry and Molecular Biology, 45(6):515-520, 2017. © 2017 The International Union of Biochemistry and Molecular Biology.

[Efficacy of using zinc oxide nanoparticles in nutrition. Experiments on the laboratory animal].

PubMed

Raspopov, R V; Trushina, E N; Mustafina, O K; Tananova, O N; Gmoshinskiĭ, I V; Khotimchenko, S A

2011-01-01

In experiments on rats there was researched bioavailability of zinc oxide (ZnO) nanoparticles. There were determined the content of Zn in blood serum and tibia, intestinal uptake of macromolecules of egg albumin, some hematological, biochemical and immune indices, liver cells apoptosis. The results obtained show that the uptake of nanoparticles of ZnO enables restoration of this microelement status damaged by zinc deficit diet.

Laboratory experiment on the 3D tide-induced Lagrangian residual current using the PIV technique

NASA Astrophysics Data System (ADS)

Chen, Yang; Jiang, Wensheng; Chen, Xu; Wang, Tao; Bian, Changwei

2017-12-01

The 3D structure of the tide-induced Lagrangian residual current was studied using the particle image velocimetry (PIV) technique in a long shallow narrow tank in the laboratory. At the mouth of the tank, a wave generator was used to make periodic wave which represents the tide movement, and at the head of the tank, a laterally sloping topography with the length of one fifth of the water tank was installed, above which the tide-induced Lagrangian residual current was studied. Under the weakly nonlinear condition in the present experiment setup, the results show that the Lagrangian residual velocity (LRV) field has a three-layer structure. The residual current flows inwards (towards the head) in the bottom layer and flows outwards in the middle layer, while in the surface layer, it flows inwards along the shallow side of the sloping topography and outwards along the deep side. The depth-averaged and breadth-averaged LRV are also analyzed based on the 3D LRV observations. Our results are in good agreement with the previous experiment studies, the analytical solutions with similar conditions and the observational results in real bays. Moreover, the volume flux comparison between the Lagrangian and Eulerian residual currents shows that the Eulerian residual velocity violates the mass conservation law while the LRV truly represents the inter-tidal water transport. This work enriches the laboratory studies of the LRV and offers valuable references for the LRV studies in real bays.

The Effect of Rain on Air-Water Gas Exchange

NASA Technical Reports Server (NTRS)

Ho, David T.; Bliven, Larry F.; Wanninkhof, Rik; Schlosser, Peter

1997-01-01

The relationship between gas transfer velocity and rain rate was investigated at NASA's Rain-Sea Interaction Facility (RSIF) using several SF, evasion experiments. During each experiment, a water tank below the rain simulator was supersaturated with SF6, a synthetic gas, and the gas transfer velocities were calculated from the measured decrease in SF6 concentration with time. The results from experiments with IS different rain rates (7 to 10 mm/h) and 1 of 2 drop sizes (2.8 or 4.2 mm diameter) confirm a significant and systematic enhancement of air-water gas exchange by rainfall. The gas transfer velocities derived from our experiment were related to the kinetic energy flux calculated from the rain rate and drop size. The relationship obtained for mono-dropsize rain at the RSIF was extrapolated to natural rain using the kinetic energy flux of natural rain calculated from the Marshall-Palmer raindrop size distribution. Results of laboratory experiments at RSIF were compared to field observations made during a tropical rainstorm in Miami, Florida and show good agreement between laboratory and field data.

Inversion algorithms for the microwave remote sensing of soil moisture. Experiments with swept frequency microwaves

NASA Technical Reports Server (NTRS)

Hancock, G. D.; Waite, W. P.

1984-01-01

Two experiments were performed employing swept frequency microwaves for the purpose of investigating the reflectivity from soil volumes containing both discontinuous and continuous changes in subsurface soil moisture content. Discontinuous moisture profiles were artificially created in the laboratory while continuous moisture profiles were induced into the soil of test plots by the environment of an agricultural field. The reflectivity for both the laboratory and field experiments was measured using bi-static reflectometers operated over the frequency ranges of 1.0 to 2.0 GHz and 4.0 to 8.0 GHz. Reflectivity models that considered the discontinuous and continuous moisture profiles within the soil volume were developed and compared with the results of the experiments. This comparison shows good agreement between the smooth surface models and the measurements. In particular the comparison of the smooth surface multi-layer model for continuous moisture profiles and the yield experiment measurements points out the sensitivity of the specular component of the scattered electromagnetic energy to the movement of moisture in the soil.

Comet assay in reconstructed 3D human epidermal skin models--investigation of intra- and inter-laboratory reproducibility with coded chemicals.

PubMed

Reus, Astrid A; Reisinger, Kerstin; Downs, Thomas R; Carr, Gregory J; Zeller, Andreas; Corvi, Raffaella; Krul, Cyrille A M; Pfuhler, Stefan

2013-11-01

Reconstructed 3D human epidermal skin models are being used increasingly for safety testing of chemicals. Based on EpiDerm™ tissues, an assay was developed in which the tissues were topically exposed to test chemicals for 3h followed by cell isolation and assessment of DNA damage using the comet assay. Inter-laboratory reproducibility of the 3D skin comet assay was initially demonstrated using two model genotoxic carcinogens, methyl methane sulfonate (MMS) and 4-nitroquinoline-n-oxide, and the results showed good concordance among three different laboratories and with in vivo data. In Phase 2 of the project, intra- and inter-laboratory reproducibility was investigated with five coded compounds with different genotoxicity liability tested at three different laboratories. For the genotoxic carcinogens MMS and N-ethyl-N-nitrosourea, all laboratories reported a dose-related and statistically significant increase (P < 0.05) in DNA damage in every experiment. For the genotoxic carcinogen, 2,4-diaminotoluene, the overall result from all laboratories showed a smaller, but significant genotoxic response (P < 0.05). For cyclohexanone (CHN) (non-genotoxic in vitro and in vivo, and non-carcinogenic), an increase compared to the solvent control acetone was observed only in one laboratory. However, the response was not dose related and CHN was judged negative overall, as was p-nitrophenol (p-NP) (genotoxic in vitro but not in vivo and non-carcinogenic), which was the only compound showing clear cytotoxic effects. For p-NP, significant DNA damage generally occurred only at doses that were substantially cytotoxic (>30% cell loss), and the overall response was comparable in all laboratories despite some differences in doses tested. The results of the collaborative study for the coded compounds were generally reproducible among the laboratories involved and intra-laboratory reproducibility was also good. These data indicate that the comet assay in EpiDerm™ skin models is a promising model for the safety assessment of compounds with a dermal route of exposure.

Comet assay in reconstructed 3D human epidermal skin models—investigation of intra- and inter-laboratory reproducibility with coded chemicals

PubMed Central

Pfuhler, Stefan

2013-01-01

Reconstructed 3D human epidermal skin models are being used increasingly for safety testing of chemicals. Based on EpiDerm™ tissues, an assay was developed in which the tissues were topically exposed to test chemicals for 3h followed by cell isolation and assessment of DNA damage using the comet assay. Inter-laboratory reproducibility of the 3D skin comet assay was initially demonstrated using two model genotoxic carcinogens, methyl methane sulfonate (MMS) and 4-nitroquinoline-n-oxide, and the results showed good concordance among three different laboratories and with in vivo data. In Phase 2 of the project, intra- and inter-laboratory reproducibility was investigated with five coded compounds with different genotoxicity liability tested at three different laboratories. For the genotoxic carcinogens MMS and N-ethyl-N-nitrosourea, all laboratories reported a dose-related and statistically significant increase (P < 0.05) in DNA damage in every experiment. For the genotoxic carcinogen, 2,4-diaminotoluene, the overall result from all laboratories showed a smaller, but significant genotoxic response (P < 0.05). For cyclohexanone (CHN) (non-genotoxic in vitro and in vivo, and non-carcinogenic), an increase compared to the solvent control acetone was observed only in one laboratory. However, the response was not dose related and CHN was judged negative overall, as was p-nitrophenol (p-NP) (genotoxic in vitro but not in vivo and non-carcinogenic), which was the only compound showing clear cytotoxic effects. For p-NP, significant DNA damage generally occurred only at doses that were substantially cytotoxic (>30% cell loss), and the overall response was comparable in all laboratories despite some differences in doses tested. The results of the collaborative study for the coded compounds were generally reproducible among the laboratories involved and intra-laboratory reproducibility was also good. These data indicate that the comet assay in EpiDerm™ skin models is a promising model for the safety assessment of compounds with a dermal route of exposure. PMID:24150594

Interactive virtual optical laboratories

NASA Astrophysics Data System (ADS)

Liu, Xuan; Yang, Yi

2017-08-01

Laboratory experiences are essential for optics education. However, college students have limited access to advanced optical equipment that is generally expensive and complicated. Hence there is a need for innovative solutions to expose students to advanced optics laboratories. Here we describe a novel approach, interactive virtual optical laboratory (IVOL) that allows unlimited number of students to participate the lab session remotely through internet, to improve laboratory education in photonics. Although students are not physically conducting the experiment, IVOL is designed to engage students, by actively involving students in the decision making process throughout the experiment.

Occurrence, leaching, and degradation of Cry1Ab protein from transgenic maize detritus in agricultural streams

DOE PAGES

Griffiths, Natalie A.; Tank, Jennifer L.; Royer, Todd V.; ...

2017-03-15

The insecticidal Cry1Ab protein expressed by transgenic (Bt) maize can enter adjacent water bodies via multiple pathways, but its fate in stream ecosystems is not as well studied as in terrestrial systems. In this study, we used a combination of field sampling and laboratory experiments to examine the occurrence, leaching, and degradation of soluble Cry1Ab protein derived from Bt maize in agricultural streams. We surveyed 11 agricultural streams in northwestern Indiana, USA, on 6 dates that encompassed the growing season, crop harvest, and snowmelt/spring flooding, and detected Cry1Ab protein in the water column and in flowing subsurface tile drains atmore » concentrations of 3–60 ng/L. In a series of laboratory experiments, submerged Bt maize leaves leached Cry1Ab into stream water with 1% of the protein remaining in leaves after 70 d. Laboratory experiments suggested that dissolved Cry1Ab protein degraded rapidly in microcosms containing water-column microorganisms, and light did not enhance breakdown by stimulating assimilatory uptake of the protein by autotrophs. Here, the common detection of Cry1Ab protein in streams sampled across an agricultural landscape, combined with laboratory studies showing rapid leaching and degradation, suggests that Cry1Ab may be pseudo-persistent at the watershed scale due to the multiple input pathways from the surrounding terrestrial environment.« less

Occurrence, leaching, and degradation of Cry1Ab protein from transgenic maize detritus in agricultural streams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Griffiths, Natalie A.; Tank, Jennifer L.; Royer, Todd V.

The insecticidal Cry1Ab protein expressed by transgenic (Bt) maize can enter adjacent water bodies via multiple pathways, but its fate in stream ecosystems is not as well studied as in terrestrial systems. In this study, we used a combination of field sampling and laboratory experiments to examine the occurrence, leaching, and degradation of soluble Cry1Ab protein derived from Bt maize in agricultural streams. We surveyed 11 agricultural streams in northwestern Indiana, USA, on 6 dates that encompassed the growing season, crop harvest, and snowmelt/spring flooding, and detected Cry1Ab protein in the water column and in flowing subsurface tile drains atmore » concentrations of 3–60 ng/L. In a series of laboratory experiments, submerged Bt maize leaves leached Cry1Ab into stream water with 1% of the protein remaining in leaves after 70 d. Laboratory experiments suggested that dissolved Cry1Ab protein degraded rapidly in microcosms containing water-column microorganisms, and light did not enhance breakdown by stimulating assimilatory uptake of the protein by autotrophs. Here, the common detection of Cry1Ab protein in streams sampled across an agricultural landscape, combined with laboratory studies showing rapid leaching and degradation, suggests that Cry1Ab may be pseudo-persistent at the watershed scale due to the multiple input pathways from the surrounding terrestrial environment.« less

SAGE Validations of Volcanic Jet Simulations

NASA Astrophysics Data System (ADS)

Peterson, A. H.; Wohletz, K. H.; Ogden, D. E.; Gisler, G.; Glatzmaier, G.

2006-12-01

The SAGE (SAIC Adaptive Grid Eulerian) code employs adaptive mesh refinement in solving Eulerian equations of complex fluid flow desirable for simulation of volcanic eruptions. Preliminary eruption simulations demonstrate its ability to resolve multi-material flows over large domains where dynamics are concentrated in small regions. In order to validate further application of this code to numerical simulation of explosive eruption phenomena, we focus on one of the fundamental physical processes important to the problem, namely the dynamics of an underexpanded jet. Observations of volcanic eruption plumes and laboratory experiments on analog systems document the eruption of overpressured fluid in a supersonic jet that is governed by vent diameter and level of overpressure. The jet is dominated by inertia (very high Reynolds number) and feeds a thermally convective plume controlled by turbulent admixture of the atmosphere. The height above the vent at which the jet looses its inertia is important to know for convective plume predictions that are used to calculate atmospheric dispersal of volcanic products. We simulate a set of well documented laboratory experiments that provide detail on underexpanded jet structure by gas density contours, showing the shape and size of the Mach stem. SAGE results are within several percent of the experiments for position and density of the incident (intercepting) and reflected shocks, slip lines, shear layers, and Mach disk. The simulations also resolve vorticity at the jet margins near the Mach disk, showing turbulent velocity fields down to a scale of 30 micrometers. Benchmarking these results with those of CFDLib (Los Alamos National Laboratory), which solves the full Navier-Stokes equations (includes viscous stress tensor), shows close agreement, indicating that adaptive mesh refinement used in SAGE may offset the need for explicit calculation of viscous dissipation.

Avoiding the approach trap: a response bias theory of the emotional Stroop effect.

PubMed

Chajut, Eran; Mama, Yaniv; Levy, Leora; Algom, Daniel

2010-11-01

In the laboratory, people classify the color of emotion-laden words slower than they do that of neutral words, the emotional Stroop effect. Outside the laboratory, people react to features of emotion-laden stimuli or threatening stimuli faster than they do to those of neutral stimuli. A possible resolution to the conundrum implicates the counternatural response demands imposed in the laboratory that do not, as a rule, provide for avoidance in the face of threat. In 2 experiments we show that when such an option is provided in the laboratory, the response latencies follow those observed in real life. These results challenge the dominant attention theory offered for the emotional Stroop effect because this theory is indifferent to the vital approach-avoidance distinction.

Integrating teaching and research in the field and laboratory settings

NASA Astrophysics Data System (ADS)

Wang, L.; Kaseke, K. F.; Daryanto, S.; Ravi, S.

2015-12-01

Field observations and laboratory measurements are great ways to engage students and spark students' interests in science. Typically these observations are separated from rigorous classroom teaching. Here we assessed the potential of integrating teaching and research in the field and laboratory setting in both US and abroad and worked with students without strong science background to utilize simple laboratory equipment and various environmental sensors to conduct innovative projects. We worked with students in Namibia and two local high school students in Indianapolis to conduct leaf potential measurements, soil nutrient extraction, soil infiltration measurements and isotope measurements. The experience showed us the potential of integrating teaching and research in the field setting and working with people with minimum exposure to modern scientific instrumentation to carry out creative projects.

The Timing of an Experiment in the Laboratory Program Is Crucial for the Student Laboratory Experience: Acylation of Ferrocene as a Case Study

ERIC Educational Resources Information Center

Southam, Daniel C.; Shand, Bradley; Buntine, Mark A.; Kable, Scott H.; Read, Justin R.; Morris, Jonathan C.

2013-01-01

An assessment of the acylation of ferrocene laboratory exercise across three successive years resulted in a significant fluctuation in student perception of the experiment. This perception was measured by collecting student responses to an instrument immediately after the experiment, which includes Likert and open-ended responses from the student.…

A comparison of traditional physical laboratory and computer-simulated laboratory experiences in relation to engineering undergraduate students' conceptual understandings of a communication systems topic

NASA Astrophysics Data System (ADS)

Javidi, Giti

2005-07-01

This study was designed to investigate an alternative to the use of traditional physical laboratory activities in a communication systems course. Specifically, this study examined whether as an alternative, computer simulation is as effective as physical laboratory activities in teaching college-level electronics engineering education students about the concepts of signal transmission, modulation and demodulation. Eighty undergraduate engineering students participated in the study, which was conducted at a southeastern four-year university. The students were randomly assigned to two groups. The groups were compared on understanding the concepts, remembering the concepts, completion time of the lab experiments and perception toward the laboratory experiments. The physical group's (n = 40) treatment was to conduct laboratory experiments in a physical laboratory. The students in this group used equipment in a controlled electronics laboratory. The Simulation group's (n = 40) treatment was to conduct similar experiments in a PC laboratory. The students in this group used a simulation program in a controlled PC lab. At the completion of the treatment, scores on a validated conceptual test were collected once after the treatment and again three weeks after the treatment. Attitude surveys and qualitative study were administered at the completion of the treatment. The findings revealed significant differences, in favor of the simulation group, between the two groups on both the conceptual post-test and the follow-up test. The findings also revealed significant correlation between simulation groups' attitude toward the simulation program and their post-test scores. Moreover, there was a significant difference between the two groups on their attitude toward their laboratory experience in favor of the simulation group. In addition, there was significant difference between the two groups on their lab completion time in favor of the simulation group. At the same time, the qualitative research has uncovered several issues not explored by the quantitative research. It was concluded that incorporating the recommendations acquired from the qualitative research, especially elements of incorporating hardware experience to avoid lack of hands-on skills, into the laboratory pedagogy should help improve students' experience regardless of the environment in which the laboratory is conducted.

Educational area for learning of optics and technologies: union of open laboratories of ideas, methods and practices (OLIMP)

NASA Astrophysics Data System (ADS)

Ivashchenko, Maksim; Bodrov, Kirill; Tolstoba, Nadezhda

2016-09-01

The paper deals with the concept of creating the union of Open Laboratories of Ideas, Methods and Practices (OLIMP). It describes the structure designed to simplify the relationship, such as business incubators, start-up accelerators, small innovative enterprises, fabrication laboratories and student centers. We consider their advantages and disadvantages for the specific audience of students and enthusiasts who do not have funding for their own projects. The experience of interaction between the Open Laboratories of Ideas, Methods and Practices and the Student Research Laboratory for Optical Engineering shows the relative impact of structures on each other and the value of using such interaction in the learning process. The paper also addresses issues such as: the motivation of students, enthusiasm for the direction the lab participants identify and maintain the initiatives, profiling in the design, scientific, commercial, social sphere.

A Content Analysis of General Chemistry Laboratory Manuals for Evidence of Higher-Order Cognitive Tasks

NASA Astrophysics Data System (ADS)

Domin, Daniel S.

1999-01-01

The science laboratory instructional environment is ideal for fostering the development of problem-solving, manipulative, and higher-order thinking skills: the skills needed by today's learner to compete in an ever increasing technology-based society. This paper reports the results of a content analysis of ten general chemistry laboratory manuals. Three experiments from each manual were examined for evidence of higher-order cognitive activities. Analysis was based upon the six major cognitive categories of Bloom's Taxonomy of Educational Objectives: knowledge, comprehension, application, analysis, synthesis, and evaluation. The results of this study show that the overwhelming majority of general chemistry laboratory manuals provide tasks that require the use of only the lower-order cognitive skills: knowledge, comprehension, and application. Two of the laboratory manuals were disparate in having activities that utilized higher-order cognition. I describe the instructional strategies used within these manuals to foster higher-order cognitive development.

Detection and molecular identification of Cryptosporidium species in laboratory rats (Rattus norvegicus) in Ibadan, Nigeria

PubMed

Ayinmode, Adekunle Bamidele; Ogbonna, Nkeiruka Fortunate; Widmer, Giovanni

To study the occurrence of Cryptosporidium infection in laboratory rats (Rattus norvegicus) raised for experimental usage, 134 faecal samples were obtained from two rearing houses in Ibadan and examined for the presence of Cryptosporidium oocyst using the modified acid fast staining technique. Cryptosporidium species in 2 samples positive for microscopy were further characterized by a nested polymerase chain reaction (PCR) amplifying the 18S rRNA gene. Two of 134 samples were positive for the Cryptosporidium oocysts. Sequencing of the small-subunit rRNA amplicons identified the species in the two PCR positive samples as Cryptosporidium andersoni and Cryptosporidium rat genotype. These findings showed that laboratory rat is a potential reservoir for diverse Cryptosporidium species and suggests that laboratory rats should be screened for Cryptosporidium infection prior to experiments, especially where pathogen free animals are not available. This the first report to identify Cryptosporidium species infecting laboratory rats in Nigeria.

Integrated biomarker response index used in laboratory exposure of the mussel Mytilus edulis to water accommodated fractions of crude oil

NASA Astrophysics Data System (ADS)

Yuan, Mengqi; Wang, You; Zhang, Xinxin; Hu, Shunxin; Tang, Xuexi

2017-03-01

Oil pollution is a serious environmental problem in coastal areas and to set up a quantitative evaluation method in monitoring the environmental pollution is of great importance. Individuals of Mytilus edulis, collected from the coastal area of Qingdao, were thus exposed to the water accommodated fractions (WAFs) of crude oil under controlled lab conditions. Mussels were exposed to different concentrations of WAFs for 96h acute toxicity experiment and 15d chronic toxicity experiment, a 7d restoration experiment was conducted after toxicity experiment as well. The activities of the antioxidant enzymes (CAT, GST, GPx and GR) were measured in gills of mussels. The purpose of the study was to screen out a series of sensitive biomarkers and set up an Integrated Biomarker Response index (IBR) for marine oil pollution monitoring. Results showed: (1) WAFs exposure induced the increased activities of CAT, GST, GPx and GR in gills, revealing a stimulation effect on the antioxidant system. Activities of enzymes were more significantly altered in response to higher concentrations of WAFs (2.3 and 5.0 mg.L-1) than lower concentrations (0.5 and 1.1 mg.L-1). After restoration experiment, the activities decreased to the initial levels. (2) IBR was set up base on the laboratory experiment, which showed a positive relationship with WAFs exposure concentrations. Therefore, IBR was suggested to be a potentially useful tool in assessing the oil pollution.

Investigating Student Perceptions of the Chemistry Laboratory and Their Approaches to Learning in the Laboratory

NASA Astrophysics Data System (ADS)

Berger, Spencer Granett

This dissertation explores student perceptions of the instructional chemistry laboratory and the approaches students take when learning in the laboratory environment. To measure student perceptions of the chemistry laboratory, a survey instrument was developed. 413 students responded to the survey during the Fall 2011 semester. Students' perception of the usefulness of the laboratory in helping them learn chemistry in high school was related to several factors regarding their experiences in high school chemistry. Students' perception of the usefulness of the laboratory in helping them learn chemistry in college was also measured. Reasons students provided for the usefulness of the laboratory were categorized. To characterize approaches to learning in the laboratory, students were interviewed midway through semester (N=18). The interviews were used to create a framework describing learning approaches that students use in the laboratory environment. Students were categorized into three levels: students who view the laboratory as a requirement, students who believe that the laboratory augments their understanding, and students who view the laboratory as an important part of science. These categories describe the types of strategies students used when conducting experiments. To further explore the relationship between students' perception of the laboratory and their approaches to learning, two case studies are described. These case studies involve interviews in the beginning and end of the semester. In the interviews, students reflect on what they have learned in the laboratory and describe their perceptions of the laboratory environment. In order to encourage students to adopt higher-level approaches to learning in the laboratory, a metacognitive intervention was created. The intervention involved supplementary questions that students would answer while completing laboratory experiments. The questions were designed to encourage students to think critically about the laboratory procedures. In order to test the effects of the intervention, an experimental group (N=87) completed these supplementary questions during two laboratory experiments while a control group (N=84) performed the same experiments without these additional questions. The effects of the intervention on laboratory exam performance were measured. Students in the experimental group had a higher average on the laboratory exam than students in the control group.

STS-98 Onboard Photograph-U.S. Laboratory, Destiny

NASA Technical Reports Server (NTRS)

2001-01-01

This STS-98 Shuttle mission image shows an overall interior view of the newly attached U.S. Laboratory, Destiny. The American-made Destiny module is the cornerstone for space-based research aboard the orbiting platform and the centerpiece of the International Space Station (ISS), where unprecedented science experiments will be performed in the near-zero gravity of space. Destiny will also serve as the command and control center for the ISS. The aluminum module is 8.5-meters (28-feet) long and 4.3-meters (14-feet) in diameter. The laboratory consists of three cylindrical sections and two endcones with hatches that will be mated to other station components. A 50.9-centimeter (20-inch-) diameter window is located on one side of the center module segment. This pressurized module is designed to accommodate pressurized payloads. It has a capacity of 24 rack locations. Payload racks will occupy 15 locations especially designed to support experiments. The Destiny module was built by the Boeing Company under the direction of the Marshall Space Flight Center.

Beneficial effects of aluminum enrichment on nitrogen-fixing cyanobacteria in the South China Sea.

PubMed

Liu, Jiaxing; Zhou, Linbin; Ke, Zhixin; Li, Gang; Shi, Rongjun; Tan, Yehui

2018-04-01

Few studies focus on the effects of aluminum (Al) on marine nitrogen-fixing cyanobacteria, which play important roles in the ocean nitrogen cycling. To examine the effects of Al on the nitrogen-fixing cyanobacteria, bioassay experiments in the oligotrophic South China Sea (SCS) and culture of Crocosphaera watsonii in the laboratory were conducted. Field data showed that 200 nM Al stimulated the growth and the nitrogenase gene expression of Trichodesmium and unicellular diazotrophic cyanobacterium group A, and the nitrogen fixation rates of the whole community. Laboratory experiments demonstrated that Al stimulated the growth and nitrogen fixation of C. watsonii under phosphorus limited conditions. Both field and laboratory results indicated that Al could stimulate the growth of diazotrophs and nitrogen fixation in oligotrophic oceans such as the SCS, which is likely related to the utilization of phosphorus, implying that Al plays an important role in the ocean nitrogen and carbon cycles by influencing nitrogen fixation. Copyright © 2018 Elsevier Ltd. All rights reserved.

Biodiesel waste as source of organic carbon for municipal WWTP denitrification.

PubMed

Bodík, I; Blstáková, A; Sedlácek, S; Hutnan, M

2009-04-01

This paper presents the results of experiments to test biodiesel waste (glycerine--g-phase) as an organic carbon source for the removal of nitrate in a WWTP denitrification process. Investigation of g-phase was first centered on g-phase utilization as an external source for denitrification under laboratory conditions and consequently, after positive results from the laboratory investigation, g-phase was applied in the denitrification process in the WWTP Vrútky (35,000 PE). This WWTP had insufficient nitrogen removal via denitrification. Denitrification was insufficient due to an influent with a low BOD5/N ratio (1.7:1) entering into the activated sludge tank. Laboratory experiments and calculations showed that, to reach Ntotal concentration under 10 mg l(-1) in effluent, a biodiesel waste dose of 500 kg(COD) d(-1) was necessary. Glycerol phase (g-phase) dosing into the denitrification tank increased denitrification efficiency by 2.0 - 5.0 mg(NO)(3)(-N)l(-1) per 100 l of g-phase dose into the denitrification tank.

A New Way to Generate Collimated Plasma Jets?

NASA Astrophysics Data System (ADS)

Young, Rachel; Kuranz, C. C.; Sweeney, R. M.; Drake, R. P.

2012-05-01

We may have a new way to generate collimated, high-Mach-number plasma jets for laboratory astrophysics experiments. Analytic calculations show that irradiating the rear side of a cone-shaped foil can produce a collimated plasma jet with a Mach number of more than 2. Preliminary numeric simulations confirm this. We intend to test this method with a day of experiments at OMEGA (Laboratory for Laser Energetics, Rochester, New York) in April 2012; results may be available in time for this meeting. If successful, this will be the first step in an experimental campaign to investigate the affects of magnetic fields on mixing plasma jets. We hope to create a swirling disk of magnetized plasma_and possibly witness the turbulent dynamo_by firing roughly half a dozen such jets towards each other. However, for such an experiment to succeed, the disk must rotate more quickly than it expands, requiring the contributing jets to have M > 2. This work is funded by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, grant number DE-FG52-09NA29548, and by the National Laser User Facility Program, grant number DE-NA0000850.

Laboratory and numerical decompression experiments: an insight into the nucleation and growth of bubbles

NASA Astrophysics Data System (ADS)

Spina, L.; Colucci, S.; De'Michieli Vitturi, M.; Scheu, B.; Dingwell, D. B.

2014-12-01

Numerical modeling, joined with experimental investigations, is fundamental for studying the dynamics of magmatic fluid into the conduit, where direct observations are unattainable. Furthermore, laboratory experiments can provide invaluable data to vunalidate complex multiphase codes. With the aim on unveil the essence of nucleation process, as well as the behavior of the multiphase magmatic fluid, we performed slow decompression experiments in a shock tube system. We choose silicon oil as analogue for the magmatic melt, and saturated it with Argon at 10 MPa for 72h. The slow decompression to atmospheric conditions was monitored through a high speed camera and pressure sensors, located into the experimental conduit. The experimental conditions of the decompression process have then been reproduced numerically with a compressible multiphase solver based on OpenFOAM. Numerical simulations have been performed by the OpenFOAM compressibleInterFoam solver for 2 compressible, non-isothermal immiscible fluids, using a VOF (volume of fluid) phase-fraction based interface capturing approach. The data extracted from 2D images obtained from laboratory analyses were compared to the outcome of numerical investigation, showing the capability of the model to capture the main processes studied.

Discovering New Light States at Neutrino Experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Essig, Rouven; /SLAC; Harnik, Roni

2011-08-11

Experiments designed to measure neutrino oscillations also provide major opportunities for discovering very weakly coupled states. In order to produce neutrinos, experiments such as LSND collide thousands of Coulombs of protons into fixed targets, while MINOS and MiniBooNE also focus and then dump beams of muons. The neutrino detectors beyond these beam dumps are therefore an excellent arena in which to look for long-lived pseudoscalars or for vector bosons that kinetically mix with the photon. We show that these experiments have significant sensitivity beyond previous beam dumps, and are able to partially close the gap between laboratory experiments and supernovaemore » constraints on pseudoscalars. Future upgrades to the NuMI beamline and Project X will lead to even greater opportunities for discovery. We also discuss thin target experiments with muon beams, such as those available in COMPASS, and show that they constitute a powerful probe for leptophilic PNGBs.« less

Asking the Next Generation: The Implementation of Pre-University Students' Ideas about Physics Laboratory Preparation Exercises

ERIC Educational Resources Information Center

Dunnett, K.; Bartlett, P. A.

2018-01-01

It was planned to introduce online pre-laboratory session activities to a first-year undergraduate physics laboratory course to encourage a minimum level of student preparation for experiments outside the laboratory environment. A group of 16 and 17 year old laboratory work-experience students were tasked to define and design a pre-laboratory…

Plate-rate laboratory friction experiments reveal potential slip instability on weak faults

NASA Astrophysics Data System (ADS)

Ikari, M.; Kopf, A.

2016-12-01

In earthquake science, it is commonly assumed that earthquakes nucleate on strong patches or "asperities", and data from laboratory friction experiments indicate a tendency for unstable slip (exhibited as velocity-weakening frictional behavior) in strong geologic materials. However, an overwhelming amount of these experiments were conducted at driving velocities ranging from 0.1 µm/s to over 1 m/s. Less data exists for shearing experiments driven at slow velocities on the order of cm/yr (nm/s), approximating plate tectonic rates which represent the natural driving condition on plate boundary faults. Recent laboratory work using samples recovered from the Tohoku region at the Japan Trench, within the high coseismic slip region of the 2011 M9 Tohoku earthquake, showed that the fault is extremely weak with a friction coefficient < 0.2. At sliding velocities of at least 0.1 µm/s mostly velocity-strengthening friction is observed, which is favorable for stable creep, consistent with earlier work. However, shearing at an imposed rate of 8.5 cm/yr produced both velocity-weakening friction and discrete slow slip events, which are likely instances of frictional instabilities or quasi-instabilities. Here, we expand on the Tohoku experiment by conducting cm/yr friction experiments on natural gouges obtained from a variety of other major fault zones obtained by scientific drilling; these include the San Andreas Fault, Costa Rica subduction zone, Nankai Trough (Japan), Barbados subduction zone, Alpine Fault (New Zealand), southern Cascadia, and Woodlark Basin (Papua New Guinea). We focus here on weak fault materials having a friction coefficient of < 0.5. At conventional laboratory driving rates of 0.1-30 µm/s, velocity strengthening is common. However, at cm/yr driving rates we commonly observe velocity-weakening friction and slow slip events, with most samples exhibit both behaviors. These results demonstrate when fault samples are sheared at plate tectonic rates in the laboratory, which best replicates natural forcing conditions, a tendency for unstable slip is revealed. Thus, weak faults should not be considered frictionally stable, but have the ability to participate in earthquake rupture or generate events themselves.

Development of guided inquiry-based laboratory worksheet on topic of heat of combustion

NASA Astrophysics Data System (ADS)

Sofiani, D.; Nurhayati; Sunarya, Y.; Suryatna, A.

2018-03-01

Chemistry curriculum reform shows an explicit shift from traditional approach to scientific inquiry. This study aims to develop a guided inquiry-based laboratory worksheet on topic of heat of combustion. Implementation of this topic in high school laboratory is new because previously some teachers only focused the experiment on determining the heat of neutralization. The method used in this study was development research consisted of three stages: define, design, and develop. In the define stage, curriculum analysis and material analysis were performed. In the design stage, laboratory optimization and product preparation were conducted. In the development stage, the product was evaluated by the experts and tested to a total of 20 eleventh-grade students. The instruments used in this study were assessment sheet and students’ response questionnaire. The assessment results showed that the guided inquiry-based laboratory worksheet has very good quality based on the aspects of content, linguistic, and graphics. The students reacted positively to the use of this guided inquiry-based worksheet as demonstrated by the results from questionnaire. The implications of this study is the laboratory activity should be directed to development of scientific inquiry skills in order to enhance students’ competences as well as the quality of science education.

Mixing-dependent Reactions in the Hyporheic Zone: Laboratory and Numerical Experiments

NASA Astrophysics Data System (ADS)

Santizo, K. Y.; Eastes, L. A.; Hester, E. T.; Widdowson, M.

2017-12-01

The hyporheic zone is the surface water-groundwater interface surrounding the river's perimeter. Prior research demonstrates the ability of the hyporheic zone to attenuate pollutants when surface water cycles through reactive sediments (non-mixing-dependent reactions). However, the colocation of both surface and ground water within hyporheic sediments also allows mixing-dependent reactions that require mixing of reactants from these two water sources. Recent modeling studies show these mixing zones can be small under steady state homogeneous conditions, but do not validate those results in the laboratory or explore the range of hydrological characteristics that control the extent of mixing. Our objective was to simulate the mixing zone, quantify its thickness, and probe its hydrological controls using a "mix" of laboratory and numerical experiments. For the lab experiments, a hyporheic zone was simulated in a sand mesocosm, and a mixing-dependent abiotic reaction of sodium sulfite and dissolved oxygen was induced. Oxygen concentration response and oxygen consumption were visualized via planar optodes. Sulfate production by the mixing-dependent reaction was measured by fluid samples and a spectrophometer. Key hydrologic controls varied in the mesocosm included head gradient driving hyporheic exchange and hydraulic conductivity/heterogeneity. Results show a clear mixing area, sulfate production, and oxygen gradient. Mixing zone length (hyporheic flow cell size) and thickness both increase with the driving head gradient. For the numerical experiments, transient surface water boundary conditions were implemented together with heterogeneity of hydraulic conductivity. Results indicate that both fluctuating boundary conditions and heterogeneity increase mixing-dependent reaction. The hyporheic zone is deemed an attenuation hotspot by multiple studies, but here we demonstrate its potential for mixing-dependent reactions and the influence of important hydrological parameters.

The influence of dissolved oxygen on winter habitat selection by largemouth bass: an integration of field biotelemetry studies and laboratory experiments.

PubMed

Hasler, C T; Suski, C D; Hanson, K C; Cooke, S J; Tufts, B L

2009-01-01

In this study, field biotelemetry and laboratory physiology approaches were coupled to allow understanding of the behavioral and physiological responses of fish to winter hypoxia. The biotelemetry study compared dissolved oxygen levels measured throughout the winter period with continually tracked locations of nine adult largemouth bass obtained from a whole-lake submerged telemetry array. Fish habitat usage was compared with habitat availability to assess whether fish were selecting for specific dissolved oxygen concentrations. The laboratory study examined behavioral and physiological responses to progressive hypoxia in juvenile largemouth bass acclimated to winter temperatures. Results from the dissolved oxygen measurements made during the biotelemetry study showed high variance in under-ice dissolved oxygen levels. Avoidance of water with dissolved oxygen <2.0 mg/L by telemetered fish was demonstrated, but significant use of water with intermediate dissolved oxygen levels was also found. Results from the lab experiments showed marked changes in behavior (i.e., yawning and vertical movement) at <2.0 mg/L of dissolved oxygen but no change in tissue lactate, an indicator of anaerobic metabolism. Combined results of the biotelemetry and laboratory studies demonstrate that a dissolved oxygen content of 2.0 mg/L may be a critical threshold that induces behavioral responses by largemouth bass during the winter. In addition, the use by fish of areas with intermediate levels of dissolved oxygen suggests that there are multiple environmental factors influencing winter behavior.

Chemical Remediation of Nickel(II) Waste: A Laboratory Experiment for General Chemistry Students

ERIC Educational Resources Information Center

Corcoran, K. Blake; Rood, Brian E.; Trogden, Bridget G.

2011-01-01

This project involved developing a method to remediate large quantities of aqueous waste from a general chemistry laboratory experiment. Aqueous Ni(II) waste from a general chemistry laboratory experiment was converted into solid nickel hydroxide hydrate with a substantial decrease in waste volume. The remediation method was developed for a…

A Laboratory Experiment on the Statistical Theory of Nuclear Reactions

ERIC Educational Resources Information Center

Loveland, Walter

1971-01-01

Describes an undergraduate laboratory experiment on the statistical theory of nuclear reactions. The experiment involves measuring the relative cross sections for formation of a nucleus in its meta stable excited state and its ground state by applying gamma-ray spectroscopy to an irradiated sample. Involves 3-4 hours of laboratory time plus…

Redefining Authentic Research Experiences in Introductory Biology Laboratories and Barriers to Their Implementation

ERIC Educational Resources Information Center

Spell, Rachelle M.; Guinan, Judith A.; Miller, Kristen R.; Beck, Christopher W.

2014-01-01

Incorporating authentic research experiences in introductory biology laboratory classes would greatly expand the number of students exposed to the excitement of discovery and the rigor of the scientific process. However, the essential components of an authentic research experience and the barriers to their implementation in laboratory classes are…

Synthesis and Biological Testing of Penicillins: An Investigative Approach to the Undergraduate Teaching Laboratory

ERIC Educational Resources Information Center

Whitaker, Ragnhild D.; Truhlar, Laura M.; Yksel, Deniz; Walt, David R.; Williams, Mark D.

2010-01-01

The development and implementation of a research-based organic chemistry laboratory experiment is presented. The experiment was designed to simulate a scientific research environment, involve students in critical thinking, and develop the student's ability to analyze and present research-based data. In this experiment, a laboratory class…

A Laboratory Experiment for Rapid Determination of the Stability of Vitamin C

ERIC Educational Resources Information Center

Adem, Seid M.; Lueng, Sam H.; Elles, Lisa M. Sharpe; Shaver, Lee Alan

2016-01-01

Experiments in laboratory manuals intended for general, organic, and biological (GOB) chemistry laboratories include few opportunities for students to engage in instrumental methods of analysis. Many of these students seek careers in modern health-related fields where experience in spectroscopic techniques would be beneficial. A simple, rapid,…

Development, Evaluation and Use of a Student Experience Survey in Undergraduate Science Laboratories: The Advancing Science by Enhancing Learning in the Laboratory Student Laboratory Learning Experience Survey

NASA Astrophysics Data System (ADS)

Barrie, Simon C.; Bucat, Robert B.; Buntine, Mark A.; Burke da Silva, Karen; Crisp, Geoffrey T.; George, Adrian V.; Jamie, Ian M.; Kable, Scott H.; Lim, Kieran F.; Pyke, Simon M.; Read, Justin R.; Sharma, Manjula D.; Yeung, Alexandra

2015-07-01

Student experience surveys have become increasingly popular to probe various aspects of processes and outcomes in higher education, such as measuring student perceptions of the learning environment and identifying aspects that could be improved. This paper reports on a particular survey for evaluating individual experiments that has been developed over some 15 years as part of a large national Australian study pertaining to the area of undergraduate laboratories-Advancing Science by Enhancing Learning in the Laboratory. This paper reports on the development of the survey instrument and the evaluation of the survey using student responses to experiments from different institutions in Australia, New Zealand and the USA. A total of 3153 student responses have been analysed using factor analysis. Three factors, motivation, assessment and resources, have been identified as contributing to improved student attitudes to laboratory activities. A central focus of the survey is to provide feedback to practitioners to iteratively improve experiments. Implications for practitioners and researchers are also discussed.

The pathogen Batrachochytrium dendrobatidis disturbs the frog skin microbiome during a natural epidemic and experimental infection

PubMed Central

Jani, Andrea J.; Briggs, Cheryl J.

2014-01-01

Symbiotic microbial communities may interact with infectious pathogens sharing a common host. The microbiome may limit pathogen infection or, conversely, an invading pathogen can disturb the microbiome. Documentation of such relationships during naturally occurring disease outbreaks is rare, and identifying causal links from field observations is difficult. This study documented the effects of an amphibian skin pathogen of global conservation concern [the chytrid fungus Batrachochytrium dendrobatidis (Bd)] on the skin-associated bacterial microbiome of the endangered frog, Rana sierrae, using a combination of population surveys and laboratory experiments. We examined covariation of pathogen infection and bacterial microbiome composition in wild frogs, demonstrating a strong and consistent correlation between Bd infection load and bacterial community composition in multiple R. sierrae populations. Despite the correlation between Bd infection load and bacterial community composition, we observed 100% mortality of postmetamorphic frogs during a Bd epizootic, suggesting that the relationship between Bd and bacterial communities was not linked to variation in resistance to mortal disease and that Bd infection altered bacterial communities. In a controlled experiment, Bd infection significantly altered the R. sierrae microbiome, demonstrating a causal relationship. The response of microbial communities to Bd infection was remarkably consistent: Several bacterial taxa showed the same response to Bd infection across multiple field populations and the laboratory experiment, indicating a somewhat predictable interaction between Bd and the microbiome. The laboratory experiment demonstrates that Bd infection causes changes to amphibian skin bacterial communities, whereas the laboratory and field results together strongly support Bd disturbance as a driver of bacterial community change during natural disease dynamics. PMID:25385615

How-to-Do-It: A Practical Method for Teaching Seed Stratification.

ERIC Educational Resources Information Center

Englert, Karen M.; Shontz, Nancy N.

1989-01-01

Described is a laboratory procedure for teaching seed stratification. Materials, methods, results, and applicability of the experiment are explained. Diagrams showing the percent of total germination as a function of stratification time and the germination rate of stratified seeds are included. (RT)

Physiological Reactivity and Recent Life-Stress Experience.

ERIC Educational Resources Information Center

Pardine, Peter; Napoli, Anthony

1983-01-01

Assessed differences in cardiovascular reactivity between high and low life-stress students (N=26). Results indicated high life-stress individuals maintained their elevated stressor levels throughout recovery from a laboratory stressor, and showed significantly higher systolic recovery levels compared to the low stress group. (JAC)

Food Choice in the Common Snail (Helix Aspersa).

ERIC Educational Resources Information Center

Gill, John; Howell, Pauline

1985-01-01

The easily obtained common snail shows interesting dietary preferences which can be the source of several simple experiments. Specific student instructions are given for quantitative and comparative studies using cabbage, lettuce, carrot, rutabaga, and onion. Suggestions for laboratory setup and further work are included. (DH)

An accelerating precursor to predict "time-to-failure" in creep and volcanic eruptions

NASA Astrophysics Data System (ADS)

Hao, Shengwang; Yang, Hang; Elsworth, Derek

2017-09-01

Real-time prediction by monitoring of the evolution of response variables is a central goal in predicting rock failure. A linear relation Ω˙Ω¨-1 = C(tf - t) has been developed to describe the time to failure, where Ω represents a response quantity, C is a constant and tf represents the failure time. Observations from laboratory creep failure experiments and precursors to volcanic eruptions are used to test the validity of the approach. Both cumulative and simple moving window techniques are developed to perform predictions and to illustrate the effects of data selection on the results. Laboratory creep failure experiments on granites show that the linear relation works well during the final approach to failure. For blind prediction, the simple moving window technique is preferred because it always uses the most recent data and excludes effects of early data deviating significantly from the predicted trend. When the predicted results show only small fluctuations, failure is imminent.

Forecasting volcanic eruptions and other material failure phenomena: An evaluation of the failure forecast method

NASA Astrophysics Data System (ADS)

Bell, Andrew F.; Naylor, Mark; Heap, Michael J.; Main, Ian G.

2011-08-01

Power-law accelerations in the mean rate of strain, earthquakes and other precursors have been widely reported prior to material failure phenomena, including volcanic eruptions, landslides and laboratory deformation experiments, as predicted by several theoretical models. The Failure Forecast Method (FFM), which linearizes the power-law trend, has been routinely used to forecast the failure time in retrospective analyses; however, its performance has never been formally evaluated. Here we use synthetic and real data, recorded in laboratory brittle creep experiments and at volcanoes, to show that the assumptions of the FFM are inconsistent with the error structure of the data, leading to biased and imprecise forecasts. We show that a Generalized Linear Model method provides higher-quality forecasts that converge more accurately to the eventual failure time, accounting for the appropriate error distributions. This approach should be employed in place of the FFM to provide reliable quantitative forecasts and estimate their associated uncertainties.

Design and Implementation of Instructional Videos for Upper-Division Undergraduate Laboratory Courses

ERIC Educational Resources Information Center

Schmidt-McCormack, Jennifer A.; Muniz, Marc N.; Keuter, Ellie C.; Shaw, Scott K.; Cole, Renée S.

2017-01-01

Well-designed laboratories can help students master content and science practices by successfully completing the laboratory experiments. Upper-division chemistry laboratory courses often present special challenges for instruction due to the instrument intensive nature of the experiments. To address these challenges, particularly those associated…

A 13-Week Research-Based Biochemistry Laboratory Curriculum

ERIC Educational Resources Information Center

Lefurgy, Scott T.; Mundorff, Emily C.

2017-01-01

Here, we present a 13-week research-based biochemistry laboratory curriculum designed to provide the students with the experience of engaging in original research while introducing foundational biochemistry laboratory techniques. The laboratory experience has been developed around the directed evolution of an enzyme chosen by the instructor, with…

Inducing Mutations in "Paramecium": An Inquiry-Based Approach

ERIC Educational Resources Information Center

Elwess, Nancy L.; Latourelle, Sandra L.

2004-01-01

A major challenge in teaching any college level general genetics course including a laboratory component is having the students actively understand the research part of an experiment as well as develop the necessary laboratory skills. This laboratory experience furthers the students' knowledge of genetics while improving their laboratory skills.…

Development, Evaluation and Use of a Student Experience Survey in Undergraduate Science Laboratories: The Advancing Science by Enhancing Learning in the Laboratory Student Laboratory Learning Experience Survey

ERIC Educational Resources Information Center

Barrie, Simon C.; Bucat, Robert B.; Buntine, Mark A.; Burke da Silva, Karen; Crisp, Geoffrey T.; George, Adrian V.; Jamie, Ian M.; Kable, Scott H.; Lim, Kieran F.; Pyke, Simon M.; Read, Justin R.; Sharma, Manjula D.; Yeung, Alexandra

2015-01-01

Student experience surveys have become increasingly popular to probe various aspects of processes and outcomes in higher education, such as measuring student perceptions of the learning environment and identifying aspects that could be improved. This paper reports on a particular survey for evaluating individual experiments that has been developed…

Professional behaviors, sense of belonging, and professional socialization of early career clinical laboratory scientists

NASA Astrophysics Data System (ADS)

Schill, Janna Marie

Professional socialization is a process that individuals experience as members of a profession and consists of the knowledge, attitudes, and experiences that influence and shape their professional identity. The process of professional socialization has not been studied in the clinical laboratory science profession. Clinical laboratory science is an allied health profession that is faced by a workforce shortage that has been caused by a decrease in new graduates, decreased retention of qualified professionals, and increased retirements. Other allied health professions such as nursing, athletic training, and pharmacy have studied professional socialization as a way to identify factors that may influence the retention of early career professionals. This mixed method study, which quantitatively used Hall's Professionalism Scale (1968) in addition to qualitative focus group interviews, sought to identify the professional attitudes and behaviors, sense of belonging, and professional socialization of early career clinical laboratory scientists. Early career clinical laboratory scientists were divided into two groups based upon the amount of work experience they had; new clinical laboratory science graduates have had less than one year of work experience and novice clinical laboratory scientists had between one and three years of work experience. This study found that early career clinical laboratory scientists have established professional identities and view themselves as members of the clinical laboratory science field within four proposed stages of professional socialization consisting of pre-arrival, encounter, adaptation, and commitment. New CLS graduates and novice clinical laboratory scientists were found to be at different stages of the professional stage process. New CLS graduates, who had less than one year of work experience, were found to be in the encounter stage. Novice clinical laboratory scientists, with one to three years of work experience, were found to be in the adaptation stage. In order for early career clinical laboratory scientists to successfully transition from student to committed professional, increased support from more experienced colleagues needs to be provided for this group of laboratory professionals. This study provided an initial examination of the professional socialization process in the CLS profession and adds to existing professional socialization studies in allied health.

The Effect of the Laboratory Specimen on Fatigue Crack Growth Rate

NASA Technical Reports Server (NTRS)

Forth, S. C.; Johnston, W. M.; Seshadri, B. R.

2006-01-01

Over the past thirty years, laboratory experiments have been devised to develop fatigue crack growth rate data that is representative of the material response. The crack growth rate data generated in the laboratory is then used to predict the safe operating envelope of a structure. The ability to interrelate laboratory data and structural response is called similitude. In essence, a nondimensional term, called the stress intensity factor, was developed that includes the applied stresses, crack size and geometric configuration. The stress intensity factor is then directly related to the rate at which cracks propagate in a material, resulting in the material property of fatigue crack growth response. Standardized specimen configurations and experimental procedures have been developed for laboratory testing to generate crack growth rate data that supports similitude of the stress intensity factor solution. In this paper, the authors present laboratory fatigue crack growth rate test data and finite element analyses that show similitude between standard specimen configurations tested using the constant stress ratio test method is unobtainable.

Sr-90 Immobilization by Infiltration of a Ca-Citrate-PO4 Solution into the Hanford 100-N Area Vadose Zone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Szecsody, Jim E.; Fruchter, Jonathan S.; Burns, Carolyn A.

This project was initiated to develop a strategy for infiltration of a Ca-citrate-PO4 solution in order to precipitate apatite [Ca6(PO4)10(OH)2] in desired locations in the vadose zone for Sr-90 remediation. Laboratory experiments have demonstrated that infiltration of a Ca-citrate-PO4 solution into sediments at low and high water saturation results in citrate biodegradation and formation of apatite. The citrate biodegradation rate was relatively uniform, in spite of the spatial variability of sediment microbial biomass, likely because of microbial transport processes that occur during solution infiltration. The precipitate was characterized as hydroxyapatite, and the Sr-90 substitution into apatite was shown to havemore » a half-life of 5.5 to 16 months. 1-D and 2-D laboratory infiltration experiments quantified the spatial distribution of apatite that formed during solution infiltration. Slow infiltration in 2-D experiments at low water saturation show the apatite precipitate concentrated in the upper third of the infiltration zone. More rapid 1-D infiltration studies show the apatite precipitate concentrated at greater depth.« less

Soil and Crop management: Lessons from the laboratory biosphere 2002-2004

NASA Astrophysics Data System (ADS)

Silverstone, S.; Nelson, M.; Alling, A.; Allen, J.

During the years 2002 and 2003, three closed system experiments were carried out in the "Laboratory Biosphere" facility located in Santa Fe, New Mexico. The program involved experimentation with "Hoyt" Soy Beans, USU Apogee Wheat and TU-82-155 sweet potato using a 5.37 m2 soil planting bed which was 30 cm deep. The soil texture, 40% clay, 31% sand and 28% silt (a clay loam), was collected from an organic farm in New Mexico to avoid chemical residues. Soil management practices involved minimal tillage, mulching and returning crop residues to the soil after each experiment. Between experiment #2 and #3, the top 15 cm of the soil was amended using a mix of peat moss, green sand, humates and pumice to improve soil texture, lower soil pH and increase nutrient availability. Soil analyses for all three experiments are presented to show how the soils have changed with time and how the changes relate to crop selection and rotation, soil selection and management, water management and pest control. The experience and information gained from these experiments are being applied to the future design of the Mars On Earth facility.

A Course-Based Undergraduate Research Experience Investigating p300 Bromodomain Mutations#

PubMed Central

Shanle, Erin K.; Tsun, Ian K.; Strahl, Brian D.

2016-01-01

Course-based undergraduate research experiences (CUREs) provide an opportunity for students to engage in experiments with outcomes that are unknown to both the instructor and students. These experiences allow students and instructors to collaboratively bridge the research laboratory and classroom, and provide research experiences for a large number of students relative to traditional individual mentored research. Here, we describe a molecular biology CURE investigating the impact of clinically relevant mutations found in the bromodomain of the p300 transcriptional regulator on acetylated histone interaction. In the CURE, students identified missense mutations in the p300 bromo-domain using the Catalogue of Somatic Mutations in Cancer (COSMIC) database and hypothesized the effects of the mutation on the acetyl-binding function of the domain. They cloned and purified the mutated bromodomain and performed peptide pulldown assays to define its potential to bind to acetylated histones. Upon completion of the course, students showed increased confidence performing molecular techniques and reported positively on doing a research project in class. In addition, results generated in the classroom were further validated in the research laboratory setting thereby providing a new model for faculty to engage in both course-based and individual undergraduate research experiences. PMID:26537758

Plasma physics and environmental perturbation laboratory. [magnetospheric experiments from space shuttle

NASA Technical Reports Server (NTRS)

Vogl, J. L.

1973-01-01

Current work aimed at identifying the active magnetospheric experiments that can be performed from the Space Shuttle, and designing a laboratory to carry out these experiments is described. The laboratory, known as the PPEPL (Plasma Physics and Environmental Perturbation Laboratory) consists of 35-ft pallet of instruments connected to a 25-ft pressurized control module. The systems deployed from the pallet are two 50-m booms, two subsatellites, a high-power transmitter, a multipurpose accelerator, a set of deployable canisters, and a gimbaled instrument platform. Missions are planned to last seven days, during which two scientists will carry out experiments from within the pressurized module. The type of experiments to be performed are outlined.

A practical hybrid model of application, integration, and competencies at interactive table conferences in histology (ITCH).

PubMed

Ettarh, Rajunor

2016-05-06

Significant changes have been implemented in the way undergraduate medical education is structured. One of the challenges for component courses such as histology in medical and dental curricula is to restructure and deliver training within new frameworks. This article describes the process of aligning the purpose and experience in histology laboratory to the goal of applying knowledge gained to team-based medical practice at Tulane University School of Medicine. Between 2011 and 2015, 711 medical students took either a traditional laboratory-based histology course (353 students) or a team-based hybrid histology course with active learning in laboratory (358 students). The key difference was in the laboratory component of the hybrid course - interactive table conferences in histology-during which students developed new competencies by working in teams, reviewing images, solving problems by applying histology concepts, and sharing learning. Content, faculty and online resources for microscopy were the same in both courses. More student-student and student-faculty interactions were evident during the hybrid course but student evaluation ratings and grades showed reductions following introduction of table conferences when compared to previous ratings. However, outcomes at National Board of Medical Examiners(®) (NBME(®) ) Subject Examination in Histology and Cell Biology showed significant improvement (72.4 ± 9.04 and 76.44 ± 9.36 for percent correct answers, traditional and hybrid courses, respectively, P < 0.0001). This model of table conferences to augment the traditional histology laboratory experience exemplifies the extent that restructuring enhancements can be used in currently taught courses in the undergraduate medical curriculum. Anat Sci Educ 9: 286-294. © 2016 American Association of Anatomists. © 2016 American Association of Anatomists.

A comparison of residual smear layer and erosion following different endodontic irrigation protocols tested under clinical and laboratory conditions.

PubMed

Cehreli, Zafer C; Uyanik, M Ozgur; Nagas, Emre; Tuncel, Behram; Er, Nuray; Comert, Fugen Dagli

2013-09-01

To compare the smear layer removal efficacy and erosive effects of different irrigation protocols under clinical and laboratory conditions. Mandibular third molars (n = 32) of 30-45 year-old patients were instrumented with rotary files and were randomly assigned to one of the following groups for final irrigation: (1) 5.25% NaOCl; (2) 17% EDTA; and (3) BioPure MTAD. Thereafter, the teeth were immediately extracted and processed for micromorphological investigation. In vitro specimen pairs were prepared by repeating the clinical experiments on freshly-extracted mandibular third molars. To compare open and closed systems, laboratory experiments were repeated on 32 additional teeth with enlarged apical foramen. The cleanliness of the root canals and the extent of erosion were assessed by environmental scanning electron microscopy. Specimens prepared under clinical and laboratory conditions had similar cleanliness and erosion scores (p > 0.05). Under both conditions, the tested solutions were more effective in removing the smear layer in the coronal and middle regions than in the apical one. Comparison of closed and open systems showed similar levels of cleanliness and erosion in all regions (p > 0.05), with the exception of 17% EDTA showing significantly higher levels of cleanliness and erosion in the apical third of open-end specimens. Based on clinical correlates of in vitro root canal cleanliness and erosion, laboratory testing of root canal irrigants on extracted teeth with closed apices can serve as a reliable method to simulate the clinical condition. EDTA was the most effective final irrigation solution in removing the smear layer at the expense of yielding the greatest erosive effect.

Adaptive Role of Inversion Polymorphism of Drosophila subobscura in Lead Stressed Environment

PubMed Central

Kenig, Bojan; Kurbalija Novičić, Zorana; Patenković, Aleksandra; Stamenković-Radak, Marina; Anđelković, Marko

2015-01-01

Local adaptation to environmental stress at different levels of genetic polymorphism in various plants and animals has been documented through evolution of heavy metal tolerance. We used samples of Drosophila subobscura populations from two differently polluted environments to analyze the change of chromosomal inversion polymorphism as genetic marker during laboratory exposure to lead. Exposure to environmental contamination can affect the genetic content within a particular inversion and produce targets for selection in populations from different environments. The aims were to discover whether the inversion polymorphism is shaped by the local natural environments, and if lead as a selection pressure would cause adaptive divergence of two populations during the multigenerational laboratory experiment. The results showed that populations retain signatures from past contamination events, and that heavy metal pollution can cause adaptive changes in population. Differences in inversion polymorphism between the two populations increased over generations under lead contamination in the laboratory. The inversion polymorphism of population originating from the more polluted natural environment was more stable during the experiment, both under conditions with and without lead. Therefore, results showed that inversion polymorphism as a genetic marker reflects a strong signature of adaptation to the local environment, and that historical demographic events and selection are important for both prediction of evolutionary potential and long-term viability of natural populations. PMID:26102201

Adaptive Role of Inversion Polymorphism of Drosophila subobscura in Lead Stressed Environment.

PubMed

Kenig, Bojan; Kurbalija Novičić, Zorana; Patenković, Aleksandra; Stamenković-Radak, Marina; Anđelković, Marko

2015-01-01

Local adaptation to environmental stress at different levels of genetic polymorphism in various plants and animals has been documented through evolution of heavy metal tolerance. We used samples of Drosophila subobscura populations from two differently polluted environments to analyze the change of chromosomal inversion polymorphism as genetic marker during laboratory exposure to lead. Exposure to environmental contamination can affect the genetic content within a particular inversion and produce targets for selection in populations from different environments. The aims were to discover whether the inversion polymorphism is shaped by the local natural environments, and if lead as a selection pressure would cause adaptive divergence of two populations during the multigenerational laboratory experiment. The results showed that populations retain signatures from past contamination events, and that heavy metal pollution can cause adaptive changes in population. Differences in inversion polymorphism between the two populations increased over generations under lead contamination in the laboratory. The inversion polymorphism of population originating from the more polluted natural environment was more stable during the experiment, both under conditions with and without lead. Therefore, results showed that inversion polymorphism as a genetic marker reflects a strong signature of adaptation to the local environment, and that historical demographic events and selection are important for both prediction of evolutionary potential and long-term viability of natural populations.

Tested Studies for Laboratory Teaching. Proceedings of the Workshop/Conference of the Association for Biology Laboratory Education (ABLE) (12th, Springfield, Missouri, June 4-8, 1990). Volume 12.

ERIC Educational Resources Information Center

Goldman, Corey A., Ed.

The focus of the Association for Biology Laboratory Education (ABLE) is to improve the undergraduate biology laboratory experience by promoting the development and dissemination of interesting, innovative, and reliable laboratory exercises. This proceedings volume includes 13 papers: "Non-Radioactive DNA Hybridization Experiments for the…

Skylab fluid mechanics simulations: Oscillation, rotation, collision and coalescence of water droplets under low-gravity environment

NASA Technical Reports Server (NTRS)

Vaughan, O. H., Jr.; Hung, R. J.

1975-01-01

Skylab 4 crew members performed a series of demonstrations showing the oscillations, rotations, as well as collision coalescence of water droplets which simulate various physical models of fluids under low gravity environment. The results from Skylab demonstrations provide information and illustrate the potential of an orbiting space-oriented research laboratory for the study of more sophisticated fluid mechanic experiments. Experiments and results are discussed.

Effect of Biochar on Greenhouse Gas Emissions and Nitrogen Cycling in Laboratory and Field Experiments

NASA Astrophysics Data System (ADS)

Hagemann, Nikolas; Harter, Johannes; Kaldamukova, Radina; Ruser, Reiner; Graeff-Hönninger, Simone; Kappler, Andreas; Behrens, Sebastian

2014-05-01

The extensive use of nitrogen (N) fertilizers in agriculture is a major source of anthropogenic N2O emissions contributing 8% to global greenhouse gas emissions. Soil biochar amendment has been suggested as a means to reduce both CO2 and non-CO2 greenhouse gas emissions. The reduction of N2O emissions by biochar has been demonstrated repeatedly in field and laboratory experiments. However, the mechanisms of the reduction remain unclear. Further it is not known how biochar field-weathering affects GHG emissions and how agro-chemicals, such as the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP), that is often simultaneously applied together with commercial N-fertilizers, impact nitrogen transformation and N2O emissions from biochar amended soils. In order investigate the duration of the biochar effect on soil N2O emissions and its susceptibility to DMPP application we performed a microcosm and field study with a high-temperature (400 ° C) beech wood derived biochar (60 t ha-1 and 5 % (w/w) biochar in the field and microcosms, respectively). While the field site contained the biochar already for three years, soil and biochar were freshly mixed for the laboratory microcosm experiments. In both studies we quantified GHG emissions and soil nitrogen speciation (nitrate, nitrite, ammonium). While the field study was carried out over the whole vegetation period of the sunflower Helianthus annuus L., soil microcosm experiments were performed for up to 9 days at 28° C. In both experiments a N-fertilizer containing DMPP was applied either before planting of the sunflowers or at the beginning of soil microcosms incubation. Laboratory microcosm experiments were performed at 60% water filled pore space reflecting average field conditions. Our results show that biochar effectively reduced soil N2O emissions by up to 60 % in the field and in the soil microcosm experiments. No significant differences in N2O emission mitigation potential between field-aged and fresh biochar were observed for the specific biochar used in this study. N2O emission reduction occurred even in the presence of DMPP in the field and in the laboratory microcosms. Our results suggest that simultaneous measurements of soil samples from the same field site in the laboratory yield similar biochar effects to those quantified in the field and that the mechanisms of N2O mitigation seem to be independent of plant growth and application of the commercial nitrification inhibitor DMPP.

Does the Lack of Hands-On Experience in a Remotely Delivered Laboratory Course Affect Student Learning?

ERIC Educational Resources Information Center

Abdel-Salam, Tarek; Kauffman, Paul J.; Crossman, Gary

2006-01-01

Educators question whether performing a laboratory experiment as an observer (non-hands-on), such as conducted in a distance education context, can be as effective a learning tool as personally performing the experiment in a laboratory environment. The present paper investigates this issue by comparing the performance of distance education…

Expression, Purification, and Characterization of a Carbohydrate-Active Enzyme: A Research-Inspired Methods Optimization Experiment for the Biochemistry Laboratory

ERIC Educational Resources Information Center

Willbur, Jaime F.; Vail, Justin D.; Mitchell, Lindsey N.; Jakeman, David L.; Timmons, Shannon C.

2016-01-01

The development and implementation of research-inspired, discovery-based experiences into science laboratory curricula is a proven strategy for increasing student engagement and ownership of experiments. In the novel laboratory module described herein, students learn to express, purify, and characterize a carbohydrate-active enzyme using modern…

Incrementally Approaching an Inquiry Lab Curriculum: Can Changing a Single Laboratory Experiment Improve Student Performance in General Chemistry?

ERIC Educational Resources Information Center

Cacciatore, Kristen L.; Sevian, Hannah

2009-01-01

Many institutions are responding to current research about how students learn science by transforming their general chemistry laboratory curricula to be inquiry-oriented. We present a comparison study of student performance after completing either a traditional or an inquiry stoichiometry experiment. This single laboratory experience was the only…

The Effect of Chemistry Laboratory Activities on Students' Chemistry Perception and Laboratory Anxiety Levels

ERIC Educational Resources Information Center

Aydogdu, Cemil

2017-01-01

Chemistry lesson should be supported with experiments to understand the lecture effectively. For safety laboratory environment and to prevent laboratory accidents; chemical substances' properties, working principles for chemical substances' usage should be learnt. Aim of the present study was to analyze the effect of experiments which depend on…

Experimental studies of two-stage centrifugal dust concentrator

NASA Astrophysics Data System (ADS)

Vechkanova, M. V.; Fadin, Yu M.; Ovsyannikov, Yu G.

2018-03-01

The article presents data of experimental results of two-stage centrifugal dust concentrator, describes its design, and shows the development of a method of engineering calculation and laboratory investigations. For the experiments, the authors used quartz, ceramic dust and slag. Experimental dispersion analysis of dust particles was obtained by sedimentation method. To build a mathematical model of the process, dust collection was built using central composite rotatable design of the four factorial experiment. A sequence of experiments was conducted in accordance with the table of random numbers. Conclusion were made.

FLASH hydrodynamic simulations of experiments to explore the generation of cosmological magnetic fields

NASA Astrophysics Data System (ADS)

Scopatz, A.; Fatenejad, M.; Flocke, N.; Gregori, G.; Koenig, M.; Lamb, D. Q.; Lee, D.; Meinecke, J.; Ravasio, A.; Tzeferacos, P.; Weide, K.; Yurchak, R.

2013-03-01

We report the results of FLASH hydrodynamic simulations of the experiments conducted by the University of Oxford High Energy Density Laboratory Astrophysics group and its collaborators at the Laboratoire pour l'Utilisation de Lasers Intenses (LULI). In these experiments, a long-pulse laser illuminates a target in a chamber filled with Argon gas, producing shock waves that generate magnetic fields via the Biermann battery mechanism. The simulations show that the result of the laser illuminating the target is a series of complex hydrodynamic phenomena.

Lab experiments are a major source of knowledge in the social sciences.

PubMed

Falk, Armin; Heckman, James J

2009-10-23

Laboratory experiments are a widely used methodology for advancing causal knowledge in the physical and life sciences. With the exception of psychology, the adoption of laboratory experiments has been much slower in the social sciences, although during the past two decades the use of lab experiments has accelerated. Nonetheless, there remains considerable resistance among social scientists who argue that lab experiments lack "realism" and generalizability. In this article, we discuss the advantages and limitations of laboratory social science experiments by comparing them to research based on nonexperimental data and to field experiments. We argue that many recent objections against lab experiments are misguided and that even more lab experiments should be conducted.

Chemistry in Microfluidic Channels

ERIC Educational Resources Information Center

Chia, Matthew C.; Sweeney, Christina M.; Odom, Teri W.

2011-01-01

General chemistry introduces principles such as acid-base chemistry, mixing, and precipitation that are usually demonstrated in bulk solutions. In this laboratory experiment, we describe how chemical reactions can be performed in a microfluidic channel to show advanced concepts such as laminar fluid flow and controlled precipitation. Three sets of…

Description of the Spacecraft Control Laboratory Experiment (SCOLE) facility

NASA Technical Reports Server (NTRS)

Williams, Jeffrey P.; Rallo, Rosemary A.

1987-01-01

A laboratory facility for the study of control laws for large flexible spacecraft is described. The facility fulfills the requirements of the Spacecraft Control Laboratory Experiment (SCOLE) design challenge for a laboratory experiment, which will allow slew maneuvers and pointing operations. The structural apparatus is described in detail sufficient for modelling purposes. The sensor and actuator types and characteristics are described so that identification and control algorithms may be designed. The control implementation computer and real-time subroutines are also described.

Description of the Spacecraft Control Laboratory Experiment (SCOLE) facility

NASA Technical Reports Server (NTRS)

Williams, Jeffrey P.; Rallo, Rosemary A.

1987-01-01

A laboratory facility for the study of control laws for large flexible spacecraft is described. The facility fulfills the requirements of the Spacecraft Control Laboratory Experiment (SCOLE) design challenge for laboratory experiments, which will allow slew maneuvers and pointing operations. The structural apparatus is described in detail sufficient for modelling purposes. The sensor and actuator types and characteristics are described so that identification and control algorithms may be designed. The control implementation computer and real-time subroutines are also described.

Biotechnology Laboratory Methods.

ERIC Educational Resources Information Center

Davis, Robert H.; Kompala, Dhinakar S.

1989-01-01

Describes a course entitled "Biotechnology Laboratory" which introduces a variety of laboratory methods associated with biotechnology. Describes the history, content, and seven experiments of the course. The seven experiments are selected from microbiology and molecular biology, kinetics and fermentation, and downstream…

The Effectiveness of Hands-on Health Informatics Skills Exercises in the Multidisciplinary Smart Home Healthcare and Health Informatics Training Laboratories.

PubMed

Sapci, A H; Sapci, H A

2017-10-01

This article aimed to evaluate the effectiveness of newly established innovative smart home healthcare and health informatics laboratories, and a novel laboratory course that focuses on experiential health informatics training, and determine students' self-confidence to operate wireless home health monitoring devices before and after the hands-on laboratory course. Two web-based pretraining and posttraining questionnaires were sent to 64 students who received hands-on training with wireless remote patient monitoring devices in smart home healthcare and health informatics laboratories. All 64 students completed the pretraining survey (100% response rate), and 49 students completed the posttraining survey (76% response rate). The quantitative data analysis showed that 95% of students had an interest in taking more hands-on laboratory courses. Sixty-seven percent of students had no prior experience with medical image, physiological data acquisition, storage, and transmission protocols. After the hands-on training session, 75.51% of students expressed improved confidence about training patients to measure blood pressure monitor using wireless devices. Ninety percent of students preferred to use a similar experiential approach in their future learning experience. Additionally, the qualitative data analysis demonstrated that students were expecting to have more courses with hands-on exercises and integration of technology-enabled delivery and patient monitoring concepts into the curriculum. This study demonstrated that the multidisciplinary smart home healthcare and health informatics training laboratories and the hands-on exercises improved students' technology adoption rates and their self-confidence in using wireless patient monitoring devices. Schattauer GmbH Stuttgart.

Unbridle biomedical research from the laboratory cage

PubMed Central

Lahvis, Garet P

2017-01-01

Many biomedical research studies use captive animals to model human health and disease. However, a surprising number of studies show that the biological systems of animals living in standard laboratory housing are abnormal. To make animal studies more relevant to human health, research animals should live in the wild or be able to roam free in captive environments that offer a natural range of both positive and negative experiences. Recent technological advances now allow us to study freely roaming animals and we should make use of them. PMID:28661398

Optimizing soft X-ray NEXAFS spectroscopy in the laboratory

NASA Astrophysics Data System (ADS)

Mantouvalou, I.; Jonas, A.; Witte, K.; Jung, R.; Stiel, H.; Kanngießer, B.

2017-05-01

Near edge X-ray absorption fine structure (NEXAFS) spectroscopy in the soft X-ray range is feasible in the laboratory using laser-produced plasma sources. We present a study using seven different target materials for optimized data analysis. The emission spectra of the materials with atomic numbers ranging from Z = 6 to Z = 79 show distinct differences, rendering the adapted selection of a suitable target material for specialized experiments feasible. For NEXAFS spectroscopy a 112.5 nm thick polyimide film is investigated as a reference exemplifying the superiority of quasi-continuum like emission spectra.

Professor Created On-line Biology Laboratory Course

NASA Technical Reports Server (NTRS)

Bowman, Arthur W.

2010-01-01

This paper will share the creation, implementation, and modification of an online college level general biology laboratory course offered for non-science majors as a part of a General Education Curriculum. The ability of professors to develop quality online laboratories will address a growing need in Higher Education as more institutions combine course sections and look for suitable alternative course delivery formats due to declining departmental budgets requiring reductions in staffing, equipment, and supplies. Also, there is an equal or greater need for more professors to develop the ability to create online laboratory experiences because many of the currently available online laboratory course packages from publishers do not always adequately parallel on-campus laboratory courses, or are not as aligned with the companion lecture sections. From a variety of scientific simulation and animation web sites, professors can easily identify material that closely fit the specific needs of their courses, instructional environment, and students that they serve. All too often, on-campus laboratory courses in the sciences provide what are termed confirmation experiences that do NOT allow students to experience science as would be carried out by scientists. Creatively developed online laboratory experiences can often provide the type of authentic investigative experiences that are not possible on-campus due to the time constraints of a typical two-hour, once-per-week-meeting laboratory course. In addition, online laboratory courses can address issues related to the need for students to more easily complete missing laboratory assignments, and to have opportunities to extend introductory exercises into more advanced undertakings where a greater sense of scientific discovery can be experienced. Professors are strongly encourages to begin creating online laboratory exercises for their courses, and to consider issues regarding assessment, copyrights, and Intellectual Property concerns.

Experiential learning in control systems laboratories and engineering project management

NASA Astrophysics Data System (ADS)

Reck, Rebecca Marie

Experiential learning is a process by which a student creates knowledge through the insights gained from an experience. Kolb's model of experiential learning is a cycle of four modes: (1) concrete experience, (2) reflective observation, (3) abstract conceptualization, and (4) active experimentation. His model is used in each of the three studies presented in this dissertation. Laboratories are a popular way to apply the experiential learning modes in STEM courses. Laboratory kits allow students to take home laboratory equipment to complete experiments on their own time. Although students like laboratory kits, no previous studies compared student learning outcomes on assignments using laboratory kits with existing laboratory equipment. In this study, we examined the similarities and differences between the experiences of students who used a portable laboratory kit and students who used the traditional equipment. During the 2014- 2015 academic year, we conducted a quasi-experiment to compare students' achievement of learning outcomes and their experiences in the instructional laboratory for an introductory control systems course. Half of the laboratory sections in each semester used the existing equipment, while the other sections used a new kit. We collected both quantitative data and qualitative data. We did not identify any major differences in the student experience based on the equipment they used. Course objectives, like research objectives and product requirements, help provide clarity and direction for faculty and students. Unfortunately, course and laboratory objectives are not always clearly stated. Without a clear set of objectives, it can be hard to design a learning experience and determine whether students are achieving the intended outcomes of the course or laboratory. In this study, I identified a common set of laboratory objectives, concepts, and components of a laboratory apparatus for undergraduate control systems laboratories. During the summer of 2015, a panel of 40 control systems faculty members, from a variety of institutions, completed a multi-round Delphi survey in order to bring them toward consensus on the common aspects of their laboratories. The following winter, 45 additional faculty members and practitioners from the control systems community completed a follow-up survey to gather feedback on the results of the Delphi survey. During the Delphi study, the panelists identified 15 laboratory objectives, 26 concepts, and 15 components that were common in their laboratories. Then in both the Delphi survey and follow-up survey each participant rated the importance of each of these items. While the average ratings differed slightly between the two groups, the order of each set of items was compared with two different tests and the order was found to be similar. Some of the common and important learning objectives include connecting theory to what is implemented and observed in the laboratory, designing controllers, and modeling and simulating systems. The most common component in both groups was Math-Works software. Some of the common concepts include block diagrams, stability, and PID control. Defining common aspects of undergraduate control systems laboratories enables common development, detailed comparisons, and simplified adaptation of equipment and experiments between campuses and programs. Throughout an undergraduate program in engineering, there are multiple opportunities for hands-on laboratory experiences that are related to course content. However, a similarly immersive experience for project management graduate students is harder to incorporate for all students in a course at once. This study explores an experiential learning opportunity for graduate students in engineering management or project management programs. The project management students enroll in a project management course. Undergraduate students interested in working on a project with a real customer enroll in a different projects course. Two students from the project management course function as project managers and lead a team of undergraduate students in the second course through a project. I studied how closely the project management experience in these courses aligns with engineering project management in industry. In the spring of 2015, I enrolled in the project management course at a large Midwestern university. I used analytic autoethnography to compare my experiences in the course with my experiences as a project engineer at a large aerospace company. I found that the experience in the course provided an authentic and comprehensive opportunity to practice most of the skills listed in the Project Management Book of Knowledge (an industry standard) as necessary for project managers. Some components of the course that made it successful: I was the project manager for the whole term, I worked with a real client, and the team defined and delivered the project before the end of the semester.

Assessing students' learning outcomes, self-efficacy and attitudes toward the integration of virtual science laboratory in general physics

NASA Astrophysics Data System (ADS)

Ghatty, Sundara L.

Over the past decade, there has been a dramatic rise in online delivery of higher education in the United States. Recent developments in web technology and access to the internet have led to a vast increase in online courses. For people who work during the day and whose complicated lives prevent them from taking courses on campus, online courses are the only alternatives by which they may achieve their goals in education. The laboratory courses are the major requirements for college and university students who want to pursue degree and certification programs in science. It is noted that there is a lack of laboratory courses in online physics courses. The present study addressed the effectiveness of a virtual science laboratory in physics instruction in terms of learning outcomes, attitudes, and self-efficacy of students in a Historically Black University College. The study included fifty-eight students (36 male and 22 female) of different science majors who were enrolled in a general physics laboratory course. They were divided into virtual and traditional groups. Three experiments were selected from the syllabus. The traditional group performed one experiment in a traditional laboratory, while the virtual group performed the same experiment in a virtual laboratory. For the second experiment, the use of laboratories by both groups was exchanged. Learner's Assessment Test (LAT), Attitudes Toward Physics Laboratories (ATPL), and Self-Efficacy Survey (SES) instruments were used. Additionally, quantitative methods such as an independent t-test, a paired t-test, and correlation statistics were used to analyze the data. The results of the first experiment indicated the learning outcomes were higher in the Virtual Laboratory than in the traditional laboratory, whereas there was no significant difference in learning outcomes with either type of lab instruction. However, significant self-efficacy gains were observed. Students expressed positive attitudes in terms of liking as well as interests in performing experiments in virtual laboratories. No gender differences were observed in learning outcomes or self-efficacy. The results of the study indicated that virtual laboratories may be a substitute for traditional laboratories to some extent, and may play a vital role in online science courses.

Normalizing the environment recapitulates adult human immune traits in laboratory mice.

PubMed

Beura, Lalit K; Hamilton, Sara E; Bi, Kevin; Schenkel, Jason M; Odumade, Oludare A; Casey, Kerry A; Thompson, Emily A; Fraser, Kathryn A; Rosato, Pamela C; Filali-Mouhim, Ali; Sekaly, Rafick P; Jenkins, Marc K; Vezys, Vaiva; Haining, W Nicholas; Jameson, Stephen C; Masopust, David

2016-04-28

Our current understanding of immunology was largely defined in laboratory mice, partly because they are inbred and genetically homogeneous, can be genetically manipulated, allow kinetic tissue analyses to be carried out from the onset of disease, and permit the use of tractable disease models. Comparably reductionist experiments are neither technically nor ethically possible in humans. However, there is growing concern that laboratory mice do not reflect relevant aspects of the human immune system, which may account for failures to translate disease treatments from bench to bedside. Laboratory mice live in abnormally hygienic specific pathogen free (SPF) barrier facilities. Here we show that standard laboratory mouse husbandry has profound effects on the immune system and that environmental changes produce mice with immune systems closer to those of adult humans. Laboratory mice--like newborn, but not adult, humans--lack effector-differentiated and mucosally distributed memory T cells. These cell populations were present in free-living barn populations of feral mice and pet store mice with diverse microbial experience, and were induced in laboratory mice after co-housing with pet store mice, suggesting that the environment is involved in the induction of these cells. Altering the living conditions of mice profoundly affected the cellular composition of the innate and adaptive immune systems, resulted in global changes in blood cell gene expression to patterns that more closely reflected the immune signatures of adult humans rather than neonates, altered resistance to infection, and influenced T-cell differentiation in response to a de novo viral infection. These data highlight the effects of environment on the basal immune state and response to infection and suggest that restoring physiological microbial exposure in laboratory mice could provide a relevant tool for modelling immunological events in free-living organisms, including humans.

Definition of experiments and instruments for a communication/navigation research laboratory. Volume 2: Experiment selection

NASA Technical Reports Server (NTRS)

1972-01-01

The selection and definition of candidate experiments and the associated experiment instrumentation requirements are described. Information is presented that addresses the following study objectives: (1) determine specific research and technology needs in the comm/nav field through a survey of the scientific/technical community; (2) develop manned low earth orbit space screening criteria and compile lists of potential candidate experiments; (3) in Blue Book format, define and describe selected candidate experiments in sufficient detail to develop laboratory configuration designs and layouts; and (4) develop experiment time phasing criteria and recommend a payload for sortie can/early laboratory missions.

Operational plans for life science payloads - From experiment selection through postflight reporting

NASA Technical Reports Server (NTRS)

Mccollum, G. W.; Nelson, W. G.; Wells, G. W.

1976-01-01

Key features of operational plans developed in a study of the Space Shuttle era life science payloads program are presented. The data describes the overall acquisition, staging, and integration of payload elements, as well as program implementation methods and mission support requirements. Five configurations were selected as representative payloads: (a) carry-on laboratories - medical emphasis experiments, (b) mini-laboratories - medical/biology experiments, (c) seven-day dedicated laboratories - medical/biology experiments, (d) 30-day dedicated laboratories - Regenerative Life Support Evaluation (RLSE) with selected life science experiments, and (e) Biomedical Experiments Scientific Satellite (BESS) - extended duration primate (Type I) and small vertebrate (Type II) missions. The recommended operational methods described in the paper are compared to the fundamental data which has been developed in the life science Spacelab Mission Simulation (SMS) test series. Areas assessed include crew training, experiment development and integration, testing, data-dissemination, organization interfaces, and principal investigator working relationships.

Definition of experiments and instruments for a communication/navigation research laboratory. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

1972-01-01

This study was undertaken to develop conceptual designs for a manned, space shuttle sortie mission laboratory capable of supporting a wide variety of experiments in conjunction with communications and navigation research. This space/laboratory would be one in which man may effectively increase experiment efficiency by certain observations, modifications, setup, calibration, and limited maintenance steps. In addition, man may monitor experiment progress and perform preliminary data evaluation to verify proper equipment functioning and may terminate or redirect experiments to obtain the most desirable end results. The flexibility and unique capabilities of man as an experimenter in such a laboratory will add greatly to the simplification of space experiments and this provides the basis for commonality in many of the supportive subsystems, thus reaping the benefits of reusability and reduced experiment costs. For Vol. 4, see N73-19268.

Low Cost Space Experiments. Study Report

DTIC Science & Technology

1991-12-06

Air Force Phillips Laboratory with Johns Hopkins University Applied Physics Laboratory . The goals of ALTAIR...Cs<- &l. LOW COST SPACE EXPERIMENTS STUDY REPORT 6 December 1991 19980302 059 Phillips Laboratory /SXL Kirtland AFB, NM 87117-6008 TVPTT" OTT...Report Corporate Author or Publisher: Phillips Laboratory /SXL, Kirtland AFB,NM 87117-6008 Publication Date: Dec 06, 1991 Pages: 176 Comments

Development and Use of Online Prelaboratory Activities in Organic Chemistry to Improve Students' Laboratory Experience

ERIC Educational Resources Information Center

Chaytor, Jennifer L.; Al Mughalaq, Mohammad; Butler, Hailee

2017-01-01

Online prelaboratory videos and quizzes were prepared for all experiments in CHEM 231, Organic Chemistry I Laboratory. It was anticipated that watching the videos would help students be better prepared for the laboratory, decrease their anxiety surrounding the laboratory, and increase their understanding of the theories and concepts presented.…

Complexometric Determination of Mercury Based on a Selective Masking Reaction

ERIC Educational Resources Information Center

Romero, Mercedes; Guidi, Veronica; Ibarrolaza, Agustin; Castells, Cecilia

2009-01-01

In the first analytical chemistry course, students are introduced to the concepts of equilibrium in water solutions and classical (non-instrumental) analytical methods. Our teaching experience shows that "real samples" stimulate students' enthusiasm for the laboratory work. From this diagnostic, we implemented an optional activity at the end of…

Culture Training: Validation Evidence for the Culture Assimilator.

ERIC Educational Resources Information Center

Mitchell, Terence R.; And Others

The culture assimilator, a programed self-instructional approach to culture training, is described and a series of laboratory experiments and field studies validating the culture assimilator are reviewed. These studies show that the culture assimilator is an effective method of decreasing some of the stress experienced when one works with people…

A Phytase Enzyme-Based Biochemistry Practical Particularly Suited to Students Undertaking Courses in Biotechnology and Environmental Science

ERIC Educational Resources Information Center

Boyce, Angela; Casey, Anne; Walsh, Gary

2004-01-01

Courses in introductory biochemistry invariably encompass basic principles of enzymology, with reinforcement of lecture-based material in appropriate laboratory practicals. Students undertaking practical classes are more enthusiastic, and generally display improved performance, when the specific experiments undertaken show direct relevance to…

The Nitric Acid Oxidation of Selected Alcohols and Ketones.

ERIC Educational Resources Information Center

Field, Kurt W.; And Others

1985-01-01

Shows that nitric acid can be used as a rapid, versatile, and economical oxidant for selected organic substances. The experiments (with background information, procedures, and results provided) require one three-hour laboratory period but could serve as open-ended projects since substrates not described could be oxidized. (JN)

Forests or floods?

Treesearch

Tim Burt; Wayne Swank

2002-01-01

This article shows how experiments at the Coweeta Hydorlogic Laboratory is North Carolina have deepened our understanding at the ways in which forested catchments respond to land use change. Drainage-basin hydrology is a popular topic, often at AS. Human impact on stream discharge as a result of changes in vegetation cover is an important theme.

Extrasolar Planets in the Classroom

ERIC Educational Resources Information Center

George, Samuel J.

2011-01-01

The field of extrasolar planets is still, in comparison with other astrophysical topics, in its infancy. There have been about 300 or so extrasolar planets detected and their detection has been accomplished by various different techniques. Here we present a simple laboratory experiment to show how planets are detected using the transit technique.…

Results of a laboratory experiment that tests rotating unbalanced-mass devices for scanning gimbaled payloads and free-flying spacecraft

NASA Technical Reports Server (NTRS)

Alhorn, D. C.; Polites, M. E.

1994-01-01

Rotating unbalanced-mass (RUM) devices are a new way to scan space-based, balloon-borne, and ground-based gimbaled payloads, like x-ray and gamma-ray telescopes. They can also be used to scan free-flying spacecraft. Circular scans, linear scans, and raster scans can be generated. A pair of RUM devices generates the basic scan motion and an auxiliary control system using torque motors, control moment gyros, or reaction wheels keeps the scan centered on the target and produces some complementary motion for raster scanning. Previous analyses and simulation results show that this approach offers significant power savings compared to scanning only with the auxiliary control system, especially with large payloads and high scan frequencies. However, these claims have never been proven until now. This paper describes a laboratory experiment which tests the concept of scanning a gimbaled payload with RUM devices. A description of the experiment is given and test results that prove the concept are presented. The test results are compared with those from a computer simulation model of the experiment and the differences are discussed.

Distribution of physical properties and timing of relative uplift in upper plate off Costa Rica: IODP Expedition 344

NASA Astrophysics Data System (ADS)

Saiki, A.; Hashimoto, Y.

2015-12-01

Evolution of physical properties in subduction zone is a key to understand lithification processes, location of decollement, and stress distribution. In this study, we examined the physical properties of sediments using on-board data and laboratory experimental data on sediments obtained off Costa Rica margin. Target sites are in the Integrate Ocean Drilling Program (IODP) Expedition 344 off Costa Rica, including reference sites (U1381 and U1414), mid-slope site (U1378, U1380) and upper-slope site (U1413). Seven samples from reference sites were analyzed. Laboratory experiments for velocity and porosity measurements were conducted with variation of effective pressure. Velocity-porosity relationships from on-board data and from laboratory experiments are comparable. The porosity-effective pressure curves under isotropic condition were converted to the curves under uniaxial condition (Teeuw, 1971). Using the normal consolidation curves under uniaxial stress conditions, we converted onboard porosity to effective pressure and fluid pressure. In reference sites, hydrostatic fluid pressure was estimated as expected as a reference sites, suggesting that porosity-effective pressure relationship was obtained correctly by experiments and it can be adapted to estimation of fluid pressure for the wedge sites. The porosity-effective pressure relationship under isotropic conditions were used for the estimation in wedge sites. In wedge sites, estimated pore pressures show lower than hydrostatic pressure, suggesting that onboard porosity was lower than that under normal compaction. The lower porosity can be caused by relative uplift from deeper portion. The amount of relative uplift can be estimated by differences in porosity-depth relationships between onboard data and experimental data. The amount of relative uplift for each site shows more than ~1000m up to ~5000m. The small error in porosity depth curve from experimental data makes relative uplift larger or smaller exponentially in the deeper portion. The increment of relative uplift, however, starts from about 1Ma in each site, suggesting some events were occurred at the timing. Laboratory experiments under differential stress should be conducted in the near future because smaller porosity is expected under differential stress conditions.

Bedrock hillslopes to deltas: New insights into landscape mechanics

NASA Astrophysics Data System (ADS)

Lamb, M. P.

2012-12-01

A powerful record of environmental history on Earth and other planets is preserved in landscapes and sedimentary deposits formed by erosion, transport and deposition of sediment. To understand this record and predict future landscape change, we need mechanistic theories for transport processes and morphodynamics. Significant progress has been made to develop and test transport laws in some settings including soil-mantled landscapes and modest gradient alluvial channels where conventional hydraulic and sediment-transport theories apply. Fundamental opportunities exist, however, to explore the physical limits of existing theories and develop new theories at the frontier of our knowledge base. In this presentation, I will describe recent case studies from sediment-source areas to depositional sinks designed to test the limits of existing transport theories and identify transitions in dominant geomorphic processes by pushing to steeper slopes, greater discharges, and dynamic boundary conditions. First, field measurements, laboratory experiments and theory suggest that sediment transport on steep, rocky hillslopes is different than on soil mantled landscapes, and may be controlled by vegetation dams and sediment release following wildfire. Second, laboratory experiments show that grain stability is enhanced in steep mountain channels compared to moderate gradient channels due to the coincident change in the ratio of flow depth to grain size, until the threshold for mass failure is surpassed. Third, field observations and theory indicate that canyons can be cut by extreme floods at rates that exceed typical river-incision rates by many orders of magnitude due to the transition from abrasion to plucking and toppling of jointed rock, with implications for megafloods on Mars. Finally, numerical modeling, laboratory experiments, and field work show that coastal rivers are coupled to their offshore plumes, and that this coupling may determine the size of deltas. These case studies illustrate that relevant processes, from turbulence to tectonics, act over a wide range of spatial and temporal scales. A major future opportunity I see is to integrate topographic and geochronologic constraints on landscape kinematics with field and laboratory experiments on process dynamics to build mechanistic transport theories applicable across human and geomorphic timescales.

Optical remote sensing of oil in the marine environment

NASA Astrophysics Data System (ADS)

Byfield, Valborg

1998-11-01

Remote sensing has played an increasing role in the routine monitoring of oil pollution and in support of the operational response to major oil pollution incidents. This study develops the technique of optical measurement for the detection of oil in the Marine Environment. A theoretical model is proposed, which relates upwelling radiance from surface oil to the optical properties of the oil in question, to the thickness of the oil layer, and to a number of ancillary environmental parameters. It is used to interpret the results of laboratory experiments in artificial and natural light, and ultimately as a tool in the analysis of airborne optical data of surface oil in the field, including the Sea Empress oil spill. Laboratory experiments showed that the thickness of surface oil may be determined using spectral ratios, and the results compared well with the predictions made by the theoretical model. Using the peak to near-infrared ratio, relative thickness estimates can be made from remote sensing data, without extensive data processing. Absolute thickness measurements are more complex, and require the knowledge of a number of environmental parameters. Both the laboratory and airborne data show that classification of oils into broad groups is possible using spectral analysis. However, the number of environmental parameters that must be considered makes this a complex task for field data. The model predicts that sheen detection will be most reliable in regions of the spectrum where the sub-surface signal is low, such as the violet to deep blue and the near-infrared. This is confirmed by the laboratory experiments in natural light, and by the airborne data from the field experiments. When water-leaving radiance is high in the near-infrared, sheen detection may be more difficult, although it should still be possible in the violet to deep blue. The theoretical model and the field data suggest that dispersed oil may be detected if concentrations are sufficiently high. The presence of suspended sediment or high concentrations of planktonic algae will, however, make this task more difficult, and success depends on a good knowledge of the background conditions.

Skylab

NASA Image and Video Library

1967-09-01

This September 1967 photograph shows workmen removing a mockup of the Saturn V S-IVB stage that housed the Skylab Orbital Workshop (OWS) from the Marshall Space Flight Center (MSFC), building 4755. The mockup was shipped to McDornell Douglas in Huntington, California for design modifications. NASA used the mockup as an engineering design tool to plan structures, equipment, and experiments for Skylab, an orbiting space laboratory. The MSFC had program management responsibility for the development of Skylab hardware and experiments, including the OWS.

The influence of children's pain memories on subsequent pain experience.

PubMed

Noel, Melanie; Chambers, Christine T; McGrath, Patrick J; Klein, Raymond M; Stewart, Sherry H

2012-08-01

Healthy children are often required to repeatedly undergo painful medical procedures (eg, immunizations). Although memory is often implicated in children's reactions to future pain, there is a dearth of research directly examining the relationship between the 2. The current study investigated the influence of children's memories for a novel pain stimulus on their subsequent pain experience. One hundred ten healthy children (60 boys) between the ages of 8 and 12 years completed a laboratory pain task and provided pain ratings. Two weeks later, children provided pain ratings based on their memories as well as their expectancies about future pain. One month following the initial laboratory visit, children again completed the pain task and provided pain ratings. Results showed that children's memory of pain intensity was a better predictor of subsequent pain reporting than their actual initial reporting of pain intensity, and mediated the relationship between initial and subsequent pain reporting. Children who had negatively estimated pain memories developed expectations of greater pain prior to a subsequent pain experience and showed greater increases in pain ratings over time than children who had accurate or positively estimated pain memories. These findings highlight the influence of pain memories on healthy children's expectations of future pain and subsequent pain experiences and extend predictive models of subsequent pain reporting. Copyright © 2012 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Release and fate of fluorocarbons in a shredder residue landfill cell: 1. Laboratory experiments.

PubMed

Scheutz, Charlotte; Fredenslund, Anders M; Nedenskov, Jonas; Kjeldsen, Peter

2010-11-01

The shredder residues from automobiles, home appliances and other metal-containing products are often disposed in landfills, as recycling technologies for these materials are not common in many countries. Shredder waste contains rigid and soft foams from cushions and insulation panels blown with fluorocarbons. The objective of this study was to use laboratory experiments to estimate fluorocarbon release and attenuation processes in a monofill shredder residue (SR) landfill cell. Waste from the open SR landfill cell at the AV Miljø landfill in Denmark was sampled at three locations. The waste contained 1-3% metal and a relatively low fraction of rigid polyurethane (PUR) foam particles. The PUR waste contained less blowing agent (CFC-11) than predicted from a release model. However, CFC-11 was steadily released in an aerobic bench scale experiment. Anaerobic waste incubation bench tests showed that SRSR produced significant methane (CH(4)), but at rates that were in the low end of the range observed for municipal solid waste. Aerobic and anaerobic batch experiments showed that processes in SRSR potentially can attenuate the fluorocarbons released from the SRSR itself: CFC-11 is degraded under anaerobic conditions with the formation of degradation products, which are being degraded under CH(4) oxidation conditions prevailing in the upper layers of the SR. Copyright © 2010 Elsevier Ltd. All rights reserved.

Involuntary conscious memory facilitates cued recall performance: further evidence that chaining occurs during voluntary recall.

PubMed

Mace, John H

2009-01-01

Recent studies have shown that conscious recollection of the past occurs spontaneously when subjects voluntarily recall their own past experiences or a list of previously studied words. Naturalistic diary studies and laboratory studies of this phenomenon, often called involuntary conscious memory (ICM), show that it occurs in 2 ways. One is direct ICM retrieval, which occurs when a cue spontaneously triggers a conscious memory; the other is chained ICM retrieval, which occurs when a retrieved conscious memory spontaneously triggers another. Laboratory studies investigating ICM show that chained ICM retrieval occurs on voluntary autobiographical memory tasks. The present results show that chained ICM retrieval also occurs on a voluntary word list memory task (cued recall). These results are among a handful suggesting that ICM retrieval routinely occurs during voluntary recall.

Hoverfly locomotor activity is resilient to external influence and intrinsic factors.

PubMed

Thyselius, Malin; Nordström, Karin

2016-01-01

Hoverflies are found across the globe, with approximately 6000 species described worldwide. Many hoverflies are being used in agriculture and some are emerging as model species for laboratory experiments. As such it is valuable to know more about their activity. Like many other dipteran flies, Eristalis hoverflies have been suggested to be strongly diurnal, but this is based on qualitative visualization by human observers. To quantify how hoverfly activity depends on internal and external factors, we here utilize a locomotor activity monitoring system. We show that Eristalis hoverflies are active during the entire light period when exposed to a 12 h light:12 h dark cycle, with a lower activity if exposed to light during the night. We show that the hoverflies' locomotor activity is stable over their lifetime and that it does not depend on the diet provided. Surprisingly, we find no difference in activity between males and females, but the activity is significantly affected by the sex of an accompanying conspecific. Finally, we show that female hoverflies are more resilient to starvation than males. In summary, Eristalis hoverflies are resilient to a range of internal and external factors, supporting their use in long-term laboratory experiments.

A Laboratory Experiment To Measure Henry's Law Constants of Volatile Organic Compounds with a Bubble Column and a Gas Chromatography Flame Ionization Detector (GC-FID)

ERIC Educational Resources Information Center

Lee, Shan-Hu; Mukherjee, Souptik; Brewer, Brittany; Ryan, Raphael; Yu, Huan; Gangoda, Mahinda

2013-01-01

An undergraduate laboratory experiment is described to measure Henry's law constants of organic compounds using a bubble column and gas chromatography flame ionization detector (GC-FID). This experiment is designed for upper-division undergraduate laboratory courses and can be implemented in conjunction with physical chemistry, analytical…

The National Ignition Facility: an experimental platform for studying behavior of matter under extreme conditions

NASA Astrophysics Data System (ADS)

Moses, Edward

2011-11-01

The National Ignition Facility (NIF), a 192-beam Nd-glass laser facility capable of producing 1.8 MJ and 500 TW of ultraviolet light, is now operational at Lawrence Livermore National Laboratory (LLNL). As the world's largest and most energetic laser system, NIF serves as the national center for the U.S. Department of Energy (DOE) and National Nuclear Security Administration to achieve thermonuclear burn in the laboratory and to explore the behavior of matter at extreme temperatures and energy densities. By concentrating the energy from all of its 192 extremely energetic laser beams into a mm3-sized target, NIF can reach the conditions required to initiate fusion reactions. NIF can also provide access to extreme scientific environments: temperatures about 100 million K, densities of 1,000 g/cm3, and pressures 100 billion times atmospheric pressure. These conditions have never been created before in a laboratory and exist naturally only in interiors of the planetary and stellar environments as well as in nuclear weapons. Since August 2009, the NIF team has been conducting experiments in support of the National Ignition Campaign (NIC)—a partnership among LLNL, Los Alamos National Laboratory, General Atomics, the University of Rochester, Sandia National Laboratories, as well as a number of universities and international collaborators. The results from these initial experiments show promise for the relatively near-term achievement of ignition. Capsule implosion experiments at energies up to 1.2 MJ have demonstrated laser energetics, radiation temperatures, and symmetry control that scale to ignition conditions. Of particular importance is the demonstration of peak hohlraum temperatures near 300 eV with overall backscatter less than 10%. Cryogenic target capability and additional diagnostics are being installed in preparation for layered target deuterium-tritium implosions to be conducted later in 2010. Important national security and basic science experiments have also been conducted on NIF. This paper describes the unprecedented experimental capabilities of NIF and the results achieved so far on the path toward ignition, for stockpile stewardship, and the beginning of frontier science experiments. The paper will also address our plans to transition NIF to a national user facility, providing access to NIF for researchers from the DOE laboratories, as well as the national and international academic and fusion energy communities.

Soil erodibility variability in laboratory and field rainfall simulations

NASA Astrophysics Data System (ADS)

Szabó, Boglárka; Szabó, Judit; Jakab, Gergely; Centeri, Csaba; Szalai, Zoltán

2017-04-01

Rainfall simulation experiments are the most common way to observe and to model the soil erosion processes in in situ and ex situ circumstances. During modelling soil erosion, one of the most important factors are the annual soil loss and the soil erodibility which represent the effect of soil properties on soil loss and the soil resistance against water erosion. The amount of runoff and soil loss can differ in case of the same soil type, while it's characteristics determine the soil erodibility factor. This leads to uncertainties regarding soil erodibility. Soil loss and soil erodibility were examined with the investigation of the same soil under laboratory and field conditions with rainfall simulators. The comparative measurement was carried out in a laboratory on 0,5 m2, and in the field (Shower Power-02) on 6 m2 plot size where the applied slope angles were 5% and 12% with 30 and 90 mm/h rainfall intensity. The main idea was to examine and compare the soil erodibility and its variability coming from the same soil, but different rainfall simulator type. The applied model was the USLE, nomograph and other equations which concern single rainfall events. The given results show differences between the field and laboratory experiments and between the different calculations. Concerning for the whole rainfall events runoff and soil loss, were significantly higher at the laboratory experiments, which affected the soil erodibility values too. The given differences can originate from the plot size. The main research questions are that: How should we handle the soil erodibility factors and its significant variability? What is the best solution for soil erodibility determination?

Field Measurements Indicate Unexpected, Serious Underestimation of Mussel Heart Rates and Thermal Tolerance by Laboratory Studies

PubMed Central

Tagliarolo, Morgana; McQuaid, Christopher D.

2016-01-01

Attempts to predict the response of species to long-term environmental change are generally based on extrapolations from laboratory experiments that inevitably simplify the complex interacting effects that occur in the field. We recorded heart rates of two genetic lineages of the brown mussel Perna perna over a full tidal cycle in-situ at two different sites in order to evaluate the cardiac responses of the two genetic lineages present on the South African coast to temperature and the immersion/emersion cycle. “Robomussel” temperature loggers were used to monitor thermal conditions at the two sites over one year. Comparison with live animals showed that robomussels provided a good estimate of mussel body temperatures. A significant difference in estimated body temperatures was observed between the sites and the results showed that, under natural conditions, temperatures regularly approach or exceed the thermal limits of P. perna identified in the laboratory. The two P. perna lineages showed similar tidal and diel patterns of heart rate, with higher cardiac activity during daytime immersion and minimal values during daytime emersion. Comparison of the heart rates measured in the field with data previously measured in the laboratory indicates that laboratory results seriously underestimate heart rate activity, by as much as 75%, especially during immersion. Unexpectedly, field estimates of body temperatures indicated an ability to tolerate temperatures considered lethal on the basis of laboratory measurements. This suggests that the interaction of abiotic conditions in the field does not necessarily raise vulnerability to high temperatures. PMID:26840775

CSI flight experiment projects of the Naval Research Laboratory

NASA Technical Reports Server (NTRS)

Fisher, Shalom

1993-01-01

The Naval Research Laboratory (NRL) is involved in an active program of CSI flight experiments. The first CSI flight experiment of the Naval Research Laboratory, the Low Power Atmospheric Compensation Experiment (LACE) dynamics experiment, has successfully measured vibrations of an orbiting satellite with a ground-based laser radar. The observations, made on January 7, 8 and 10, 1991, represent the first ever measurements of this type. In the tests, a narrowband heterodyne CO2 laser radar, operating at a wavelength of 10.6 microns, detected vibration induced differential-Doppler signatures of the LACE satellite. Power spectral densities of forced oscillations and modal frequencies and damping rates of free-damped vibrations were obtained and compared with finite element structural models of the LACE system. Another manifested flight experiment is the Advanced Controls Technology Experiment (ACTEX) designed to demonstrate active and passive damping with piezo-electric (PZT) sensors and actuators. This experiment was developed under the management of the Air Force Phillips Laboratory with integration of the experiment at NRL. It is to ride as a secondary, or 'piggyback,' experiment on a future Navy satellite.

CSI flight experiment projects of the Naval Research Laboratory

NASA Astrophysics Data System (ADS)

Fisher, Shalom

1993-02-01

The Naval Research Laboratory (NRL) is involved in an active program of CSI flight experiments. The first CSI flight experiment of the Naval Research Laboratory, the Low Power Atmospheric Compensation Experiment (LACE) dynamics experiment, has successfully measured vibrations of an orbiting satellite with a ground-based laser radar. The observations, made on January 7, 8 and 10, 1991, represent the first ever measurements of this type. In the tests, a narrowband heterodyne CO2 laser radar, operating at a wavelength of 10.6 microns, detected vibration induced differential-Doppler signatures of the LACE satellite. Power spectral densities of forced oscillations and modal frequencies and damping rates of free-damped vibrations were obtained and compared with finite element structural models of the LACE system. Another manifested flight experiment is the Advanced Controls Technology Experiment (ACTEX) designed to demonstrate active and passive damping with piezo-electric (PZT) sensors and actuators. This experiment was developed under the management of the Air Force Phillips Laboratory with integration of the experiment at NRL. It is to ride as a secondary, or 'piggyback,' experiment on a future Navy satellite.

Fluid Flow Experiment for Undergraduate Laboratory.

ERIC Educational Resources Information Center

Vilimpochapornkul, Viroj; Obot, Nsima T.

1986-01-01

The undergraduate fluid mechanics laboratory at Clarkson University consists of three experiments: mixing; drag measurements; and fluid flow and pressure drop measurements. The latter experiment is described, considering equipment needed, procedures used, and typical results obtained. (JN)

Aggregate stability, root length and root thickness influenced by a mycorrhizal inoculum? - Results from a three-year eco-engineering field experiment on an alpine slope.

NASA Astrophysics Data System (ADS)

Bast, Alexander; Wilcke, Wolfgang; Lüscher, Peter; Graf, Frank; Gärtner, Holger

2014-05-01

In mountain environments many slopes are covered by coarse grained, glacial-, periglacial- or/and denudation-derived substrate. These slopes show a high geomorphic activity and are susceptible for erosional processes, shallow landslides or debris flows, which can result in a high socio-economic hazard potential. This is especially true for steep slopes, lacking a protecting vegetation cover. Regarding hazard prevention, eco-engineering gained in importance because related techniques provide a sustainable measure to protect erosion-prone hillslopes. The idea of using plants for sustainable erosion control and protection against shallow landslides, demands some essential requirements, as e.g., a stable seedbed providing appropriate water and nutrient supply. However, degraded alpine slopes are often unstable and the coarse-grained material shows a low retention capacity of water and nutrients. Extreme conditions like this hamper a fast and sustainable development of a protecting vegetation cover even if pioneer plants are used to stabilize the slopes. Thus, the question arises what needs to be done to give planted saplings within eco-engineering projects maximum support developing their above- and belowground structures to promote slope stabilization. Laboratory experiments using potted plants have shown a positive impact of mycorrhizal fungi inoculation plant development and soil structure, i.e. the formation of (stable) aggregates within several months. Soil aggregate stability is an integrating parameter, reflecting several aspects of the plant-soil system and for this also an indicator of soil development and soil stability. Because of this and based on the promising laboratory results, we intended to apply this approach in a field-experiment We established (i) mycorrhizal and (ii) non-mycorrhizal treated eco-engineered research plots on a field experimental scale, covering a total area of approx. 1000 m2 on an ENE exposed slope (coarse morainic and denudation-derived substrate; inclination ~40 - 45 °; elevation 1220 - 1360 m a.s.l.) located in the Eastern Swiss Alps, where many environmental parameters can be seen as homogeneous. Soil aggregate stability, the formation of water stable aggregates and the fine-root development was quantified at the end of three consecutively vegetation periods. Our results show, that an impact of the mycorrhizal inoculum on aggregate stability was not traceable after one vegetation period, which contradicts our expectations and former laboratory experiments. At the mycorrhizal inoculated site, fine roots showed indeed a lower root length density compared to the non-mycorrhizal treated site, but the proportion of roots with thicker diameters tended to be higher. At the end of the third vegetation period this pattern changed. Aggregate stability is then highest at the inoculated site and root length density increased showing the highest values as well. The tendency to thicker root diameters at the mycorrhizal treated site can be confirmed. Our findings show that studies on a field experimental scale are inevitable. Laboratory experiments and field studies complement each other, and lead to a better understanding, having regard to a successful application of sustainable eco-engineering measures on erosion-prone slopes in alpine environments.

A Kinetic Experiment for the Biochemistry Laboratory.

ERIC Educational Resources Information Center

Palmer, Richard E.

1986-01-01

Discusses the use of specific reactions of metabolic pathways to make measurements in the laboratory. Describes an adaptation of an experiment used in undergraduate biochemistry laboratories involving the induction of an enzyme in E. coli, as well as its partial purification and characterization. (TW)

Immobilized alpha-Galactosidase in the Biochemistry Laboratory

ERIC Educational Resources Information Center

Mulimani, V. H.; Dhananjay, K.

2007-01-01

This laboratory experiment was designed to demonstrate the application of immobilized galactosidase in food industry to hydrolyze raffinose family oligosaccharides in soymilk. This laboratory experiment was conducted for postgraduate students of biochemistry and developed for graduate and undergraduate students of biochemistry, biotechnology,…

Environmental Assessment for Air Force Research Laboratory Space Vehicles Integrated Experiments Division Office Space at Kirtland Air Force Base, Albuquerque, New Mexico

DTIC Science & Technology

2005-06-01

AIR FORCE RESEARCH LABORATORY SPACE VEHICLES INTEGRATED EXPERMENTS DIVISION OFFICE SPACE AT KIRTLAND AIR FORCE ... Kirtland Air Force Base (KAFB). The office building would house the Air Force Research Laboratory Space Vehicles Integrated Experiments Division...ADDRESS(ES) Air Force Research Laboratory ,Space Vehicles Directorate,3550 Aberdeen Ave. SE, Kirtland

A GC-MS Analysis of an S[subscript N]2 Reaction for the Organic Laboratory

ERIC Educational Resources Information Center

Clennan, Malgorzata M.; Clennan, Edward L.

2005-01-01

The S[subscript N]2 reaction of 1-bromohexane and 1-bromobutane with potassium acetate is introduced to address the shortage of suitable laboratory experiments in organic laboratory. The experiment offers a review of some common laboratory techniques including the use of infrared spectroscopy to identify functional groups, the use of GC-MS…

Effective Laboratory Experiences for Students with Disabilities: The Role of a Student Laboratory Assistant

NASA Astrophysics Data System (ADS)

Pence, Laura E.; Workman, Harry J.; Riecke, Pauline

2003-03-01

Two separate experiences with students whose disabilities significantly limited the number of laboratory activities they could accomplish independently has given us a general experience base for determining successful strategies for accommodating students facing these situatiuons. For a student who had substantially limited physical mobility and for a student who had no visual ability, employing a student laboratory assistant allowed the students with disabilities to have a productive and positive laboratory experience. One of the priorities in these situations should be to avoid depersonalizing the student with a disability. Interactions with the instructor and with other students should focus on the disabled student rather than the student laboratory assistant who may be carrying out specific tasks. One of the most crucial aspects of a successful project is the selection of a laboratory assistant who has excellent interpersonal skills and who will add his or her creativity to that of the student with a disability to meet unforeseen challenges. Other considerations are discussed, such as the importance of advance notification that a disabled student has enrolled in a course as well as factors that should contribute to choosing an optimum laboratory station for each situation.

Experimental basis for a Titan probe organic analysis

NASA Technical Reports Server (NTRS)

Mckay, C. P.; Scattergood, T. W.; Borucki, W. J.; Kasting, J. F.; Miller, S. L.

1986-01-01

The recent Voyager flyby of Titan produced evidence for at least nine organic compounds in that atmosphere that are heavier than methane. Several models of Titan's atmosphere, as well as laboratory simulations, suggest the presence of organics considerably more complex that those observed. To ensure that the in situ measurements are definitive with respect to Titan's atmosphere, experiment concepts, and the related instrumentation, must be carefully developed specifically for such a mission. To this end, the possible composition of the environment to be analyzed must be bracketed and model samples must be provided for instrumentation development studies. Laboratory studies to define the optimum flight experiment and sampling strategy for a Titan entry probe are currently being conducted. Titan mixtures are being subjected to a variety of energy sources including high voltage electron from a DC discharge, high current electric shock, and laser detonation. Gaseous and solid products are produced which are then analyzed. Samples from these experiements are also provided to candidate flight experiments as models for instrument development studies. Preliminary results show that existing theoretical models for chemistry in Titan's atmosphere cannot adequetely explain the presence and abundance of all trace gases observed in these experiments.

Initial performance of the COSINE-100 experiment

NASA Astrophysics Data System (ADS)

Adhikari, G.; Adhikari, P.; de Souza, E. Barbosa; Carlin, N.; Choi, S.; Choi, W. Q.; Djamal, M.; Ezeribe, A. C.; Ha, C.; Hahn, I. S.; Hubbard, A. J. F.; Jeon, E. J.; Jo, J. H.; Joo, H. W.; Kang, W. G.; Kang, W.; Kauer, M.; Kim, B. H.; Kim, H.; Kim, H. J.; Kim, K. W.; Kim, M. C.; Kim, N. Y.; Kim, S. K.; Kim, Y. D.; Kim, Y. H.; Kudryavtsev, V. A.; Lee, H. S.; Lee, J.; Lee, J. Y.; Lee, M. H.; Leonard, D. S.; Lim, K. E.; Lynch, W. A.; Maruyama, R. H.; Mouton, F.; Olsen, S. L.; Park, H. K.; Park, H. S.; Park, J. S.; Park, K. S.; Pettus, W.; Pierpoint, Z. P.; Prihtiadi, H.; Ra, S.; Rogers, F. R.; Rott, C.; Scarff, A.; Spooner, N. J. C.; Thompson, W. G.; Yang, L.; Yong, S. H.

2018-02-01

COSINE is a dark matter search experiment based on an array of low background NaI(Tl) crystals located at the Yangyang underground laboratory. The assembly of COSINE-100 was completed in the summer of 2016 and the detector is currently collecting physics quality data aimed at reproducing the DAMA/LIBRA experiment that reported an annual modulation signal. Stable operation has been achieved and will continue for at least 2 years. Here, we describe the design of COSINE-100, including the shielding arrangement, the configuration of the NaI(Tl) crystal detection elements, the veto systems, and the associated operational systems, and we show the current performance of the experiment.

Comparing field investigations with laboratory models to predict landfill leachate emissions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fellner, Johann; Doeberl, Gernot; Allgaier, Gerhard

2009-06-15

Investigations into laboratory reactors and landfills are used for simulating and predicting emissions from municipal solid waste landfills. We examined water flow and solute transport through the same waste body for different volumetric scales (laboratory experiment: 0.08 m{sup 3}, landfill: 80,000 m{sup 3}), and assessed the differences in water flow and leachate emissions of chloride, total organic carbon and Kjeldahl nitrogen. The results indicate that, due to preferential pathways, the flow of water in field-scale landfills is less uniform than in laboratory reactors. Based on tracer experiments, it can be discerned that in laboratory-scale experiments around 40% of pore watermore » participates in advective solute transport, whereas this fraction amounts to less than 0.2% in the investigated full-scale landfill. Consequences of the difference in water flow and moisture distribution are: (1) leachate emissions from full-scale landfills decrease faster than predicted by laboratory experiments, and (2) the stock of materials remaining in the landfill body, and thus the long-term emission potential, is likely to be underestimated by laboratory landfill simulations.« less

Laboratory space physics: Investigating the physics of space plasmas in the laboratory

NASA Astrophysics Data System (ADS)

Howes, Gregory G.

2018-05-01

Laboratory experiments provide a valuable complement to explore the fundamental physics of space plasmas without the limitations inherent to spacecraft measurements. Specifically, experiments overcome the restriction that spacecraft measurements are made at only one (or a few) points in space, enable greater control of the plasma conditions and applied perturbations, can be reproducible, and are orders of magnitude less expensive than launching spacecraft. Here, I highlight key open questions about the physics of space plasmas and identify the aspects of these problems that can potentially be tackled in laboratory experiments. Several past successes in laboratory space physics provide concrete examples of how complementary experiments can contribute to our understanding of physical processes at play in the solar corona, solar wind, planetary magnetospheres, and the outer boundary of the heliosphere. I present developments on the horizon of laboratory space physics, identifying velocity space as a key new frontier, highlighting new and enhanced experimental facilities, and showcasing anticipated developments to produce improved diagnostics and innovative analysis methods. A strategy for future laboratory space physics investigations will be outlined, with explicit connections to specific fundamental plasma phenomena of interest.

Hawking-like radiation does not require a trapped region.

PubMed

Barceló, Carlos; Liberati, Stefano; Sonego, Sebastiano; Visser, Matt

2006-10-27

We discuss the issue of quasiparticle production by "analogue black holes" with particular attention paid to the possibility of reproducing Hawking radiation in a laboratory. By constructing simple geometric acoustic models, we obtain a somewhat unexpected result: We show that, in order to obtain a stationary and Planckian emission of quasiparticles, it is not necessary to create a trapped region in the acoustic spacetime (corresponding to a supersonic regime in the fluid flow). It is sufficient to set up a dynamically changing flow asymptotically approaching a sonic regime with sufficient rapidity in laboratory time. This result is generic to curved-space quantum field theory, the "analogue spacetimes" we consider providing a guide to physical intuition, and a possible route to laboratory experiments.

Undergraduate Organic Chemistry Laboratory Safety

NASA Astrophysics Data System (ADS)

Luckenbaugh, Raymond W.

1996-11-01

Each organic chemistry student should become familiar with the educational and governmental laboratory safety requirements. One method for teaching laboratory safety is to assign each student to locate safety resources for a specific class laboratory experiment. The student should obtain toxicity and hazardous information for all chemicals used or produced during the assigned experiment. For example, what is the LD50 or LC50 for each chemical? Are there any specific hazards for these chemicals, carcinogen, mutagen, teratogen, neurotixin, chronic toxin, corrosive, flammable, or explosive agent? The school's "Chemical Hygiene Plan", "Prudent Practices for Handling Hazardous Chemicals in the Laboratory" (National Academy Press), and "Laboratory Standards, Part 1910 - Occupational Safety and Health Standards" (Fed. Register 1/31/90, 55, 3227-3335) should be reviewed for laboratory safety requirements for the assigned experiment. For example, what are the procedures for safe handling of vacuum systems, if a vacuum distillation is used in the assigned experiment? The literature survey must be submitted to the laboratory instructor one week prior to the laboratory session for review and approval. The student should then give a short presentation to the class on the chemicals' toxicity and hazards and describe the safety precautions that must be followed. This procedure gives the student first-hand knowledge on how to find and evaluate information to meet laboartory safety requirements.

Covariation of metabolic rates and cell size in coccolithophores

NASA Astrophysics Data System (ADS)

Aloisi, G.

2015-08-01

Coccolithophores are sensitive recorders of environmental change. The size of their coccosphere varies in the ocean along gradients of environmental conditions and provides a key for understanding the fate of this important phytoplankton group in the future ocean. But interpreting field changes in coccosphere size in terms of laboratory observations is hard, mainly because the marine signal reflects the response of multiple morphotypes to changes in a combination of environmental variables. In this paper I examine the large corpus of published laboratory experiments with coccolithophores looking for relations between environmental conditions, metabolic rates and cell size (a proxy for coccosphere size). I show that growth, photosynthesis and, to a lesser extent, calcification covary with cell size when pCO2, irradiance, temperature, nitrate, phosphate and iron conditions change. With the exception of phosphate and temperature, a change from limiting to non-limiting conditions always results in an increase in cell size. An increase in phosphate or temperature (below the optimum temperature for growth) produces the opposite effect. The magnitude of the coccosphere-size changes observed in the laboratory is comparable to that observed in the ocean. If the biological reasons behind the environment-metabolism-size link are understood, it will be possible to use coccosphere-size changes in the modern ocean and in marine sediments to investigate the fate of coccolithophores in the future ocean. This reasoning can be extended to the size of coccoliths if, as recent experiments are starting to show, coccolith size reacts to environmental change proportionally to coccosphere size. The coccolithophore database is strongly biased in favour of experiments with the coccolithophore Emiliania huxleyi (E. huxleyi; 82 % of database entries), and more experiments with other species are needed to understand whether these observations can be extended to coccolithophores in general. I introduce a simple model that simulates the growth rate and the size of cells forced by nitrate and phosphate concentrations. By considering a simple rule that allocates the energy flow from nutrient acquisition to cell structure (biomass) and cell maturity (biological complexity, eventually leading to cell division), the model is able to reproduce the covariation of growth rate and cell size observed in laboratory experiments with E. huxleyi when these nutrients become limiting. These results support ongoing efforts to interpret coccosphere and coccolith size measurements in the context of climate change.

Stability of monitoring weak changes in multiply scattering media with ambient noise correlation: laboratory experiments.

PubMed

Hadziioannou, Céline; Larose, Eric; Coutant, Olivier; Roux, Philippe; Campillo, Michel

2009-06-01

Previous studies have shown that small changes can be monitored in a scattering medium by observing phase shifts in the coda. Passive monitoring of weak changes through ambient noise correlation has already been applied to seismology, acoustics, and engineering. Usually, this is done under the assumption that a properly reconstructed Green function (GF), as well as stable background noise sources, is necessary. In order to further develop this monitoring technique, a laboratory experiment was performed in the 2.5 MHz range in a gel with scattering inclusions, comparing an active (pulse-echo) form of monitoring to a passive (correlation) one. Present results show that temperature changes in the medium can be observed even if the GF of the medium is not reconstructed. Moreover, this article establishes that the GF reconstruction in the correlations is not a necessary condition: The only condition to monitoring with correlation (passive experiment) is the relative stability of the background noise structure.

Accessing the Asymmetric Collisionless Reconnection Regime in the Terrestrial Reconnection Experiment (TREX)

NASA Astrophysics Data System (ADS)

Greess, S.; Egedal, J.; Olson, J.; Millet-Ayala, A.; Myers, R.; Wallace, J.; Clark, M.; Forest, C.

2017-12-01

Kinetic effects are expected to dominate the collisionless reconnection regime, where the mean free path is large enough that the anisotropic electron pressure can develop without being damped away by collisional pitch angle scattering. In simulations, the anisotropic pressure drives the formation of outflow jets [1]. These jets are expected to play a role in the reconnection layer at the Earth's magnetopause, which is currently being explored by Magnetospheric Multiscale Mission (MMS) [2]. Until recently, this regime of anisotropic pressure was inaccessible by laboratory experiments, but new data from the Terrestrial Reconnection Experiment (TREX) shows that fully collisionless reconnection can now be achieved in the laboratory. Future runs at TREX will delve deeper into this collisionless regime in both the antiparallel and guide-field cases. [1] Le, A. et al. JPP, 81(1). doi: 10.1017/S0022377814000907. [2] Burch, J. L. et al. Space Sci. Rev. 199,5. doi: 10.1007/s11214-015-0164-9 Supported in part by NSF/DOE award DE-SC0013032.

In the white cube: museum context enhances the valuation and memory of art.

PubMed

Brieber, David; Nadal, Marcos; Leder, Helmut

2015-01-01

Art museum attendance is rising steadily, unchallenged by online alternatives. However, the psychological value of the real museum experience remains unclear because the experience of art in the museum and other contexts has not been compared. Here we examined the appreciation and memory of an art exhibition when viewed in a museum or as a computer simulated version in the laboratory. In line with the postulates of situated cognition, we show that the experience of art relies on organizing resources present in the environment. Specifically, artworks were found more arousing, positive, interesting and liked more in the museum than in the laboratory. Moreover, participants who saw the exhibition in the museum later recalled more artworks and used spatial layout cues for retrieval. Thus, encountering real art in the museum enhances cognitive and affective processes involved in the appreciation of art and enriches information encoded in long-term memory. Copyright © 2014 Elsevier B.V. All rights reserved.

Three Dimensional Hybrid Simulations of Super-Alfvénic Laser Ablation Experiments in the Large Plasma Device

NASA Astrophysics Data System (ADS)

Clark, Stephen; Winske, Dan; Schaeffer, Derek; Everson, Erik; Bondarenko, Anton; Constantin, Carmen; Niemann, Christoph

2014-10-01

We present 3D hybrid simulations of laser produced expanding debris clouds propagating though a magnetized ambient plasma in the context of magnetized collisionless shocks. New results from the 3D code are compared to previously obtained simulation results using a 2D hybrid code. The 3D code is an extension of a previously developed 2D code developed at Los Alamos National Laboratory. It has been parallelized and ported to execute on a cluster environment. The new simulations are used to verify scaling relationships, such as shock onset time and coupling parameter (Rm /ρd), developed via 2D simulations. Previous 2D results focus primarily on laboratory shock formation relevant to experiments being performed on the Large Plasma Device, where the shock propagates across the magnetic field. The new 3D simulations show wave structure and dynamics oblique to the magnetic field that introduce new physics to be considered in future experiments.

Long term fault system reorganization of convergent and strike-slip systems

NASA Astrophysics Data System (ADS)

Cooke, M. L.; McBeck, J.; Hatem, A. E.; Toeneboehn, K.; Beyer, J. L.

2017-12-01

Laboratory and numerical experiments representing deformation over many earthquake cycles demonstrate that fault evolution includes episodes of fault reorganization that optimize work on the fault system. Consequently, the mechanical and kinematic efficiencies of fault systems do not increase monotonically through their evolution. New fault configurations can optimize the external work required to accommodate deformation, suggesting that changes in system efficiency can drive fault reorganization. Laboratory evidence and numerical results show that fault reorganization within accretion, strike-slip and oblique convergent systems is associated with increasing efficiency due to increased fault slip (frictional work and seismic energy) and commensurate decreased off-fault deformation (internal work and work against gravity). Between episodes of fault reorganization, fault systems may become less efficient as they produce increasing off fault deformation. For example, laboratory and numerical experiments show that the interference and interaction between different fault segments may increase local internal work or that increasing convergence can increase work against gravity produced by a fault system. This accumulation of work triggers fault reorganization as stored work provides the energy required to grow new faults that reorganize the system to a more efficient configuration. The results of laboratory and numerical experiments reveal that we should expect crustal fault systems to reorganize following periods of increasing inefficiency, even in the absence of changes to the tectonic regime. In other words, fault reorganization doesn't require a change in tectonic loading. The time frame of fault reorganization depends on fault system configuration, strain rate and processes that relax stresses within the crust. For example, stress relaxation may keep pace with stress accumulation, which would limit the increase in the internal work and gravitational work so that irregularities can persist along active fault systems without reorganization of the fault system. Consequently, steady state behavior, for example with constant fault slip rates, may arise either in systems with high degree of stress-relaxation or occur only within the intervals between episodes of fault reorganization.

The student perspective of high school laboratory experiences

NASA Astrophysics Data System (ADS)

Lambert, R. Mitch

High school science laboratory experiences are an accepted teaching practice across the nation despite a lack of research evidence to support them. The purpose of this study was to examine the perspective of students---stakeholders often ignored---on these experiences. Insight into the students' perspective was explored progressively using a grounded theory methodology. Field observations of science classrooms led to an open-ended survey of high school science students, garnering 665 responses. Twelve student interviews then focused on the data and questions evolving from the survey. The student perspective on laboratory experiences revealed varied information based on individual experience. Concurrent analysis of the data revealed that although most students like (348/665) or sometimes like (270/665) these experiences, some consistent factors yielded negative experiences and prompted suggestions for improvement. The category of responses that emerged as the core idea focused on student understanding of the experience. Students desire to understand the why do, the how to, and the what it means of laboratory experiences. Lacking any one of these, the experience loses educational value for them. This single recurring theme crossed the boundaries of age, level in school, gender, and even the student view of lab experiences as positive or negative. This study suggests reflection on the current laboratory activities in which science teachers engage their students. Is the activity appropriate (as opposed to being merely a favorite), does it encourage learning, does it fit, does it operate at the appropriate level of inquiry, and finally what can science teachers do to integrate these activities into the classroom curriculum more effectively? Simply stated, what can teachers do so that students understand what to do, what's the point, and how that point fits into what they are learning outside the laboratory?

Activity Coefficients of Acetone-Chloroform Solutions: An Undergraduate Experiment. Undergraduate Experiment.

ERIC Educational Resources Information Center

Ozog, J. Z.; Morrison, J. A.

1983-01-01

Presents information, laboratory procedures, and results of an undergraduate experiment in which activity coefficients for a two-component liquid-vapor system are determined. Working in pairs, students can perform the experiment with 10 solutions in a given three-hour laboratory period. (Author/JN)

Habitat segregation mediates predation by the benthic fish Cottus gobio on the exotic amphipod species Gammarus roeseli

NASA Astrophysics Data System (ADS)

Kaldonski, Nicolas; Lagrue, Clément; Motreuil, Sébastien; Rigaud, Thierry; Bollache, Loïc

2008-09-01

Predation is often considered as one of the most important biotic factor determining the success of exotic species. The freshwater amphipod Gammarus roeseli has widely colonized Western Europe, where it is frequently found in sympatry with the native species ( Gammarus pulex). Previous laboratory experiments revealed that G. roeseli may have an advantage over G. pulex through differential predation by native fish (brown trout). Morphological anti-predator defences (spines) were found responsible for lower rates of predation on the invasive G. roeseli. Here, using both field surveys and laboratory experiments, we tested if a differential of predation exists with other fish predators naturally encountered by gammarids. The main predators present in our field site were nocturnal benthic feeders (mainly bullheads, Cottus gobio). Fish diet analysis showed that, compared to its global availability in the river, G. roeseli was less consumed than G. pulex. In the field, however, G. roeseli was found mainly in the aquatic vegetation whereas G. pulex was found in all habitat types. Laboratory experiments in microcosms revealed that G. roeseli was less prone to predation by C. gobio only when vegetation was present. Depending on the type of predator, the differential of predation could therefore be mediated by antipredator behaviour, and a better usage of refuges, rather than by morphological defences.

An integrated biomarker response index for the mussel Mytilus edulis based on laboratory exposure to anthracene and field transplantation experiments

NASA Astrophysics Data System (ADS)

Yuan, Mengqi; Wang, You; Zhou, Bin; Jian, Xiaoyang; Dong, Wenlong; Tang, Xuexi

2017-09-01

Organic pollution is a serious environmental problem in coastal areas and it is important to establish quantitative methods for monitoring this pollution. This study screened a series of sensitive biomarkers to construct an integrated biomarker response (IBR) index using Mytilus edulis. Mussels were exposed to the polycyclic aromatic hydrocarbon anthracene under controlled laboratory conditions and the activities of components of the glutathione antioxidant system, and the concentrations of oxidative-damage markers, were measured in the gills and digestive glands. Anthracene exposure resulted in increased levels of malondialdehyde (MDA) and superoxide radicals (O 2 • ), indicating that oxidative damage had occurred. Correspondingly, anthracene exposure induced increased activities of glutathione S-transferase (GST), glutathione peroxidase (GPx) and reduced glutathione (GSH) in digestive glands, and GPx and glutathione reductase (GR) in gills, consistent with stimulation of the antioxidant system. A field experiment was set up, in which mussels from a relatively clean area were transplanted to a contaminated site. One month later, the activities of GST, GPx and GR had increased in several tissues, particularly in the digestive glands. Based on the laboratory experiment, an IBR, which showed a positive relationship with anthracene exposure, was constructed. The IBR is suggested to be a potentially useful tool for assessing anthracene pollution.

Organism support for life sciences spacelab experiments

NASA Technical Reports Server (NTRS)

Drake, G. L.; Heppner, D. B.

1976-01-01

This paper presents an overview of the U.S. life sciences laboratory concepts envisioned for the Shuttle/Spacelab era. The basic development approach is to provide a general laboratory facility supplemented by specific experiment hardware as required. The laboratory concepts range from small carry-on laboratories to fully dedicated laboratories in the Spacelab pressurized module. The laboratories will encompass a broad spectrum of research in biology and biomedicine requiring a variety of research organisms. The environmental control and life support of these organisms is a very important aspect of the success of the space research missions. Engineering prototype organism habitats have been designed and fabricated to be compatible with the Spacelab environment and the experiment requirements. These first-generation habitat designs and their subsystems have supported plants, cells/tissues, invertebrates, and small vertebrates in limited evaluation tests. Special handling and transport equipment required for the ground movement of the experiment organisms at the launch/landing site have been built and tested using these initial habitat prototypes.

Zero-Gravity Atmospheric Cloud Physics Experiment Laboratory engineering concepts/design tradeoffs. Volume 1: Study results

NASA Technical Reports Server (NTRS)

Greco, R. V.; Eaton, L. R.; Wilkinson, H. C.

1974-01-01

The work is summarized which was accomplished from January 1974 to October 1974 for the Zero-Gravity Atmospheric Cloud Physics Laboratory. The definition and development of an atmospheric cloud physics laboratory and the selection and delineation of candidate experiments that require the unique environment of zero gravity or near zero gravity are reported. The experiment program and the laboratory concept for a Spacelab payload to perform cloud microphysics research are defined. This multimission laboratory is planned to be available to the entire scientific community to utilize in furthering the basic understanding of cloud microphysical processes and phenomenon, thereby contributing to improved weather prediction and ultimately to provide beneficial weather control and modification.

Building Diversified Multiple Trees for classification in high dimensional noisy biomedical data.

PubMed

Li, Jiuyong; Liu, Lin; Liu, Jixue; Green, Ryan

2017-12-01

It is common that a trained classification model is applied to the operating data that is deviated from the training data because of noise. This paper will test an ensemble method, Diversified Multiple Tree (DMT), on its capability for classifying instances in a new laboratory using the classifier built on the instances of another laboratory. DMT is tested on three real world biomedical data sets from different laboratories in comparison with four benchmark ensemble methods, AdaBoost, Bagging, Random Forests, and Random Trees. Experiments have also been conducted on studying the limitation of DMT and its possible variations. Experimental results show that DMT is significantly more accurate than other benchmark ensemble classifiers on classifying new instances of a different laboratory from the laboratory where instances are used to build the classifier. This paper demonstrates that an ensemble classifier, DMT, is more robust in classifying noisy data than other widely used ensemble methods. DMT works on the data set that supports multiple simple trees.

Considering whether Medicaid is worth the cost: revisiting the Oregon Health Study.

PubMed

Muennig, Peter A; Quan, Ryan; Chiuzan, Codruta; Glied, Sherry

2015-05-01

The Oregon Health Study was a groundbreaking experiment in which uninsured participants were randomized to either apply for Medicaid or stay with their current care. The study showed that Medicaid produced numerous important socioeconomic and health benefits but had no statistically significant impact on hypertension, hypercholesterolemia, or diabetes. Medicaid opponents interpreted the findings to mean that Medicaid is not a worthwhile investment. Medicaid proponents viewed the experiment as statistically underpowered and, irrespective of the laboratory values, suggestive that Medicaid is a good investment. We tested these competing claims and, using a sensitive joint test and statistical power analysis, confirmed that the Oregon Health Study did not improve laboratory values. However, we also found that Medicaid is a good value, with a cost of just $62 000 per quality-adjusted life-years gained.

Developed turbulence and nonlinear amplification of magnetic fields in laboratory and astrophysical plasmas.

PubMed

Meinecke, Jena; Tzeferacos, Petros; Bell, Anthony; Bingham, Robert; Clarke, Robert; Churazov, Eugene; Crowston, Robert; Doyle, Hugo; Drake, R Paul; Heathcote, Robert; Koenig, Michel; Kuramitsu, Yasuhiro; Kuranz, Carolyn; Lee, Dongwook; MacDonald, Michael; Murphy, Christopher; Notley, Margaret; Park, Hye-Sook; Pelka, Alexander; Ravasio, Alessandra; Reville, Brian; Sakawa, Youichi; Wan, Willow; Woolsey, Nigel; Yurchak, Roman; Miniati, Francesco; Schekochihin, Alexander; Lamb, Don; Gregori, Gianluca

2015-07-07

The visible matter in the universe is turbulent and magnetized. Turbulence in galaxy clusters is produced by mergers and by jets of the central galaxies and believed responsible for the amplification of magnetic fields. We report on experiments looking at the collision of two laser-produced plasma clouds, mimicking, in the laboratory, a cluster merger event. By measuring the spectrum of the density fluctuations, we infer developed, Kolmogorov-like turbulence. From spectral line broadening, we estimate a level of turbulence consistent with turbulent heating balancing radiative cooling, as it likely does in galaxy clusters. We show that the magnetic field is amplified by turbulent motions, reaching a nonlinear regime that is a precursor to turbulent dynamo. Thus, our experiment provides a promising platform for understanding the structure of turbulence and the amplification of magnetic fields in the universe.

Efficiency Measurement of VANDLE Modules

NASA Astrophysics Data System (ADS)

Peters, William; Matei, C.; Cizewski, J. A.; O'Malley, P. D.; Spassova, I.; Bardayan, D.; Blackmon, J. C.; Brune, C.; Massey, T.; Grzywacz, R. K.; Madurga, M.; Sarazin, F.; Raiola, F.

2010-02-01

The Versatile Array of Neutron Detectors at Low Energy (VANDLE) is a new array of plastic scintillator bars being developed at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory (ORNL). The modular design enables optimization of different configurations for particular experiments, such as (d,n) and beta-delayed neutron-decay experiments, with rare ion beams. Two prototype modules were moved to the Edwards Accelerator Laboratory at Ohio University to measure their efficiency using a calibrated ^27Al(d,n) reaction as a neutron source. Results show that one bar with a cross section of 3x3 cm^2 is over 25% efficient to neutrons around 1 MeV with sensitivity down to 100 keV neutrons. Other design features such as wrapping and coupling will be presented, as well as results from resolution tests. )

SCOUT: small chamber for optical UV tests

NASA Astrophysics Data System (ADS)

Pancrazzi, M.; Landini, F.; Romoli, M.; Totaro, M.; Pennelli, G.

2017-11-01

SCOUT is the acronym of the new facility developed within the XUVLab laboratory of the Department of Physics and Astronomy of the University of Florence. SCOUT stands for "Small Chamber for Optical UV Tests" and has been designed to perform practical and fast measurements for those experiments requiring an evacuated environment. SCOUT has been thought, designed and manufactured by paying a particular attention to its flexibility and adaptability. The functionality and the capabilities of SCOUT have been recently tested in a measurement campaign to characterize an innovative wire-grid polarizer optimized to work in transmission in the UV band. This paper provides a description of the overall manufactured system and its performance and shows the additional resources available at the XUVLab laboratory in Florence that make SCOUT exploitable by whatever compact (within 1 m) optical experiment that investigates the UV band of the spectrum.

Evaluating the effectiveness of an online medical laboratory technician program.

PubMed

Hansen-Suchy, Kara

2011-01-01

The purpose of this study was to analyze the effectiveness of an online medical laboratory technician program in the academic preparation and development of laboratory professionals. A semi-quantitative comparative research design was used. Several factors were considered in this evaluation. Academic outcomes between online and campus medical laboratory technician (MLT) students was determined by comparing overall and categorical scores on certification exams as well as first time pass rate. Certification exam scores and first time pass rates were also compared to national norms when possible to do so. Demographic data, including age and experience were compared. Additionally, learning styles were assessed to determine if there was a correlation to overall GPA and MLT GPA and if learning styles could be used to predict successful completion of an online Associates of Applied Science. The research was conducted at an academic university located in the mountain west United States. Participants consisted of online and campus students enrolled in a Medical Laboratory Technician program that graduated with their Associate of Applied Science degree between the years 2007-2009. Results of these years were also compared to graduates from 2004-2006 in the same program. Certification performance and first time pass rates were the major outcomes measured. Age and experience were correlated. Online learning styles and GPA were also compared to successful degree completion. The researcher found no significant difference in certification performance with regard to total and categorical scores, and first time pass rates between campus and online MLT students. Online students were slightly older and had more experience working in a laboratory in some capacity. Correlation studies showed significant positive correlation between learning styles, GPA, and successful completion of an Associate of Applied Science degree. When registry scores were compared to the prior cohort of online students, some subcategories scores demonstrated a significant increase using Chi-squared analysis. The research demonstrated that the online MLT students studied were as academically prepared as their campus counterparts.

Was the Driver Drunk? An Instrumental Methods Experiment for the Determination of Blood Alcohol Content.

ERIC Educational Resources Information Center

Zabzdyr, Jennifer L.; Lillard, Sheri J.

2001-01-01

Introduces a laboratory experiment for determining blood alcohol content using a combination of instrumental analysis and forensic science. Teaches the importance of careful laboratory technique and that experiments are conducted for a reason. Includes the procedure of the experiment. (Contains 17 references.) (YDS)

A Simple Photochemical Experiment for the Advanced Laboratory.

ERIC Educational Resources Information Center

Rosenfeld, Stuart M.

1986-01-01

Describes an experiment to provide students with: (1) an introduction to photochemical techniques and theory; (2) an experience with semimicro techniques; (3) an application of carbon-14 nuclear magnetic resonance; and (4) a laboratory with some qualities of a genuine experiment. These criteria are met in the photooxidation of 9,…

International Co-Operation in Control Engineering Education Using Online Experiments

ERIC Educational Resources Information Center

Henry, Jim; Schaedel, Herbert M.

2005-01-01

This paper describes the international co-operation experience in teaching control engineering with laboratories being conducted remotely by students via the Internet. This paper describes how the students ran the experiments and their personal experiences with the laboratory. A tool for process identification and controller tuning based on…

Friction Laws Derived From the Acoustic Emissions of a Laboratory Fault by Machine Learning

NASA Astrophysics Data System (ADS)

Rouet-Leduc, B.; Hulbert, C.; Ren, C. X.; Bolton, D. C.; Marone, C.; Johnson, P. A.

2017-12-01

Fault friction controls nearly all aspects of fault rupture, yet it is only possible to measure in the laboratory. Here we describe laboratory experiments where acoustic emissions are recorded from the fault. We find that by applying a machine learning approach known as "extreme gradient boosting trees" to the continuous acoustical signal, the fault friction can be directly inferred, showing that instantaneous characteristics of the acoustic signal are a fingerprint of the frictional state. This machine learning-based inference leads to a simple law that links the acoustic signal to the friction state, and holds for every stress cycle the laboratory fault goes through. The approach does not use any other measured parameter than instantaneous statistics of the acoustic signal. This finding may have importance for inferring frictional characteristics from seismic waves in Earth where fault friction cannot be measured.

International Space Station (ISS)

NASA Image and Video Library

1997-06-01

This Boeing photograph shows the Node 1, Unity module, Flight Article (at right) and the U.S. Laboratory module, Destiny, Flight Article for the International Space Station (ISS) being manufactured in the High Bay Clean Room of the Space Station Manufacturing Facility at the Marshall Space Flight Center. The Node 1, or Unity, serves as a cornecting passageway to Space Station modules. The U.S. built Unity module was launched aboard the orbiter Endeavour (STS-88 mission) on December 4, 1998 and connected to the Zarya, the Russian-built Functional Energy Block (FGB). The U.S. Laboratory (Destiny) module is the centerpiece of the ISS, where science experiments will be performed in the near-zero gravity of space. The U.S. Laboratory/Destiny was launched aboard the orbiter Atlantis (STS-98 mission) on February 7, 2001. The ISS is a multidisciplinary laboratory, technology test bed, and observatory that will provide unprecedented undertakings in scientific, technological, and international experimentation.

STS-98 Onboard Photograph-U.S. Laboratory, Destiny

NASA Technical Reports Server (NTRS)

2001-01-01

This STS-98 mission photograph shows astronauts Thomas D. Jones (foreground) and Kerneth D. Cockrell floating inside the newly installed Laboratory aboard the International Space Station (ISS). The American-made Destiny module is the cornerstone for space-based research aboard the orbiting platform and the centerpiece of the ISS, where unprecedented science experiments will be performed in the near-zero gravity of space. Destiny will also serve as the command and control center for the ISS. The aluminum module is 8.5-meters (28-feet) long and 4.3-meters (14-feet) in diameter. The laboratory consists of three cylindrical sections and two endcones with hatches that will be mated to other station components. A 50.9-centimeter (20-inch-) diameter window is located on one side of the center module segment. This pressurized module is designed to accommodate pressurized payloads. It has a capacity of 24 rack locations. Payload racks will occupy 15 locations especially designed to support experiments. The Destiny module was built by the Boeing Company under the direction of the Marshall Space Flight Center.

STS-98 Onboard Photograph-U.S. Laboratory, Destiny

NASA Technical Reports Server (NTRS)

2001-01-01

This closer image of the International Space Station (ISS) showing the newly installed U.S. Laboratory, Destiny (left), was taken from the departing Space Shuttle Atlantis. The American-made Destiny module is the cornerstone for space-based research aboard the orbiting platform and the centerpiece of the ISS, where unprecedented science experiments will be performed in the near-zero gravity of space. Destiny will also serve as the command and control center for the ISS. The aluminum module is 8.5-meters (28-feet) long and 4.3-meters (14-feet) in diameter. The laboratory consists of three cylindrical sections and two endcones with hatches that will be mated to other station components. A 50.9-centimeter (20-inch-) diameter window is located on one side of the center module segment. This pressurized module is designed to accommodate pressurized payloads. It has a capacity of 24 rack locations. Payload racks will occupy 15 locations especially designed to support experiments. The Destiny module was built by the Boeing Company under the direction of the Marshall Space Flight Center.

Laboratory plant study on the melting process of asbestos waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sakai, Shinichi; Terazono, Atsushi; Takatsuki, Hiroshi

The melting process was studied as a method of changing asbestos into non-hazardous waste and recovering it as a reusable resource. In an initial effort, the thermal behaviors of asbestos waste in terms of physical and chemical structure have been studied. Then, 10 kg/h-scale laboratory plant experiments were carried out. By X-ray diffraction analysis, the thermal behaviors of sprayed-on asbestos waste revealed that chrysotile asbestos waste change in crystal structure at around 800 C, and becomes melted slag, mainly composed of magnesium silicate, at around 1,500 C. Laboratory plant experiments on the melting process of sprayed-on asbestos have shown thatmore » melted slag can be obtained. X-ray diffraction analysis of the melted slag revealed crystal structure change, and SEM analysis showed the slag to have a non-fibrous form. And more, TEM analysis proved the very high treatment efficiency of the process, that is, reduction of the asbestos content to 1/10{sup 6} as a weight basis. These analytical results indicate the effectiveness of the melting process for asbestos waste treatment.« less

Engaging Students in Authentic Microbiology Research in an Introductory Biology Laboratory Course is Correlated with Gains in Student Understanding of the Nature of Authentic Research and Critical Thinking†

PubMed Central

Gasper, Brittany J.; Gardner, Stephanie M.

2013-01-01

Recent recommendations for biology education highlight the role of authentic research experiences early in undergraduate education as a means of increasing the number and quality of biology majors. These experiences will inform students on the nature of science, increase their confidence in doing science, as well as foster critical thinking skills, an area that has been lacking despite it being one of the desired outcomes at undergraduate institutions and with future employers. With these things in mind, we have developed an introductory biology laboratory course where students design and execute an authentic microbiology research project. Students in this course are assimilated into the community of researchers by engaging in scholarly activities such as participating in inquiry, reading scientific literature, and communicating findings in written and oral formats. After three iterations of a semester-long laboratory course, we found that students who took the course showed a significant increase in their understanding of the nature of authentic research and their level of critical thinking skills. PMID:23858351

Rapid evolution mitigates the ecological consequences of an invasive species (Bythotrephes longimanus) in lakes in Wisconsin.

PubMed

Gillis, Michael K; Walsh, Matthew R

2017-07-12

Invasive species have extensive negative consequences for biodiversity and ecosystem health. Novel species also drive contemporary evolution in many native populations, which could mitigate or amplify their impacts on ecosystems. The predatory zooplankton Bythotrephes longimanus invaded lakes in Wisconsin, USA, in 2009. This invasion caused precipitous declines in zooplankton prey ( Daphnia pulicaria ), with cascading impacts on ecosystem services (water clarity). Here, we tested the link between Bythotrephes invasion, evolution in Daphnia and post-invasion ecological dynamics using 15 years of long-term data in conjunction with comparative experiments. Invasion by Bythotrephes is associated with rapid increases in the body size of Daphnia Laboratory experiments revealed that such shifts have a genetic component; third-generation laboratory-reared Daphnia from 'invaded' lakes are significantly larger and exhibit greater reproductive effort than individuals from 'uninvaded' lakes. This trajectory of evolution should accelerate Daphnia population growth and enhance population persistence. We tested this prediction by comparing analyses of long-term data with laboratory-based simulations, and show that rapid evolution in Daphnia is associated with increased population growth in invaded lakes. © 2017 The Authors.

Prebiotic organic microstructures.

PubMed

Bassez, Marie-Paule; Takano, Yoshinori; Kobayashi, Kensei

2012-08-01

Micro- and sub-micrometer spheres, tubules and fiber-filament soft structures have been synthesized in our experiments conducted with 3 MeV proton irradiations of a mixture of simple inorganic constituents, CO, N(2) and H(2)O. We analysed the irradiation products, with scanning electron microscopy (SEM) and atomic force microscopy (AFM). These laboratory organic structures produced a wide variety of proteinaceous and non-proteinaceous amino acids after HCl hydrolysis. The enantiomer analysis for D,L-alanine confirmed that the amino acids were abiotically synthesized during the laboratory experiment. We discuss the presence of CO(2) and the production of H(2) during exothermic processes of serpentinization and consequently we discuss the production of hydrothermal CO in a ferromagnesian silicate mineral environment. We also discuss the low intensity of the Earth's magnetic field during the Paleoarchaean Era and consequently we conclude that excitation sources arising from cosmic radiation were much more abundant during this Era. We then show that our laboratory prebiotic microstructures might be synthesized during the Archaean Eon, as a product of the serpentinization process of the rocks and of their mineral contents.

Laboratory studies of the diagenesis and mobility of 239,240pu and 137Cs in nearshore sediments

NASA Astrophysics Data System (ADS)

Sholkovitz, Edward R.; Cochran, J. Kirk; Carey, Anne E.

1983-08-01

Controlled laboratory experiments have been used to study the diagenetic chemistry of 239,240Pu 137Cs, and 55Fe. Experiments using Buzzards Bay sediments in small tanks show that sulfate reduction is accompanied by the production of large pore water concentration gradients of alkalinity, phosphate, ammonia and dissolved organic carbon and the formation of subsurface maxima in Fe and Mn. These pore water profiles demonstrate that bacterially-mediated processes of organic matter degradation and redox reactions can be simulated in the laboratory. A vertical profile of 55Fe in pore waters is reported for the first time: it follows the profile of stable Fe and as such has a large (200 dpm/100 kg) subsurface maximum between 2-4 cm depth. Comparison of 55Fe/Fe ratios in sediments and pore waters shows that there is preferential solubilization of 55Fe over stable Fe. The pore water activities of 239,240Pu show no gradients within the large uncertainties of the counting statistics, but are two to four times higher than Buzzards Bay seawater (0.05 dpm/100 kg). The activity of 137Cs in the pore water profile is constant (40 dpm/100 kg) within the large counting uncertainties and is twice that of Buzzards Bay seawater. Cs-137 does not appear to be involved in diagenetic chemistry but may increase in pore waters as a result of ion exchange reactions. Flux estimates based on the pore water data show that remobilization and transport of 239,240 Pu in coastal sediments are not significant processes while the transport of l37Cs may be.

A course-based undergraduate research experience investigating p300 bromodomain mutations.

PubMed

Shanle, Erin K; Tsun, Ian K; Strahl, Brian D

2016-01-01

Course-based undergraduate research experiences (CUREs) provide an opportunity for students to engage in experiments with outcomes that are unknown to both the instructor and students. These experiences allow students and instructors to collaboratively bridge the research laboratory and classroom, and provide research experiences for a large number of students relative to traditional individual mentored research. Here, we describe a molecular biology CURE investigating the impact of clinically relevant mutations found in the bromodomain of the p300 transcriptional regulator on acetylated histone interaction. In the CURE, students identified missense mutations in the p300 bromodomain using the Catalogue of Somatic Mutations in Cancer (COSMIC) database and hypothesized the effects of the mutation on the acetyl-binding function of the domain. They cloned and purified the mutated bromodomain and performed peptide pulldown assays to define its potential to bind to acetylated histones. Upon completion of the course, students showed increased confidence performing molecular techniques and reported positively on doing a research project in class. In addition, results generated in the classroom were further validated in the research laboratory setting thereby providing a new model for faculty to engage in both course-based and individual undergraduate research experiences. © 2015 The International Union of Biochemistry and Molecular Biology.

Five years' experience of classical swine fever polymerase chain reaction ring trials in France.

PubMed

Po, F; Le Dimna, M; Le Potier, M F

2011-12-01

Since 2004, the French National Reference Laboratory for classical swine fever (CSF) has conducted an annual proficiency test (PT) to evaluate the ability of local veterinary laboratories to perform real-time polymerase chain reaction (PCR) for CSF virus. The results of five years of testing (2004-2008) are described here. The PT was conducted under blind conditions on 20 samples. The same batch of samples was used for all five years. The number of laboratories that analysed the samples increased from four in 2004 to 13 in 2008. The results of the PT showed the following: cross-contamination between samples and deficiencies in RNA preparation can occur even in experienced laboratories; sample homogeneity should be checked carefully before selection; samples stored at-80 degrees C for several years remain stable; and poor shipment conditions do not damage the samples with regard to detection of CSF virus genome. These results will enable redesign of the panel to improve the overall quality of the PT, which will encourage laboratories to check and improve their PCR procedures and expertise. This is an excellent way to determine laboratory performance.

The snowmaker: nature identical snow production in the laboratory

NASA Astrophysics Data System (ADS)

Schleef, S.; Jaggi, M.; Loewe, H.; Schneebeli, M.

2013-12-01

Using natural snow for laboratory experiments can be tricky due to shortage of winter periods and snowfall, difficulties of sample casting and transport, and the great variability of natural snow due to the varying conditions of crystal growth in the clouds. This hinders repeatable laboratory experiments with reproducible specimen and microstructural characteristics. To minimize experimental uncertainties we designed an improved machine called snowmaker, which enables us to produce nature-identical snow in a cold laboratory under well defined conditions. The snowmaker is based on well-known principles: warm humid air from a heated water basin is advected into a cold nucleation chamber where the vapor resublimates on stretched Nylon wires. Crystals are automatically harvested by a motor driven brush rack and collected in a box, thereby several kilograms of snow can be produced per day with minimum maintenance. The excess vapor is collected in a moisture trap to avoid frost in the laboratory. The entire construction is designed as a rolling, modular assembly system which can easily carried out of the laboratory for defrosting. In addition to previous attempts we focus on the reproducibility of the samples and the comparison to natural snow down to the microscale. We show that the settings of water temperature and cold laboratory temperature facilitates the production of different crystal shapes like dendrites and needles in a reproducible way. Besides photography, we analyzed the microstructure of snowmaker crystals in aggregated specimen by X-ray microtomography. Depending on the settings we can create reproducible samples with density of 50-170 kg/m3 and specific surface areas of 50-80 mm-1. We briefly touch similarities between artificial and natural snow samples with respect to crystal habit, microstructural parameters and short-time metamorphism.

MODELING SUPERSONIC-JET DEFLECTION IN THE HERBIG–HARO 110-270 SYSTEM WITH HIGH-POWER LASERS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yuan, Dawei; Li, Yutong; Lu, Xin

Herbig–Haro (HH) objects associated with newly born stars are typically characterized by two high Mach number jets ejected in opposite directions. However, HH 110 appears to only have a single jet instead of two. Recently, Kajdi et al. measured the proper motions of knots in the whole system and noted that HH 110 is a continuation of the nearby HH 270. It has been proved that the HH 270 collides with the surrounding mediums and is deflected by 58°, reshaping itself as HH 110. Although the scales of the astrophysical objects are very different from the plasmas created in themore » laboratory, similarity criteria of physical processes allow us to simulate the jet deflection in the HH 110/270 system in the laboratory with high power lasers. A controllable and repeatable laboratory experiment could give us insight into the deflection behavior. Here we show a well downscaled experiment in which a laser-produced supersonic-jet is deflected by 55° when colliding with a nearby orthogonal side-flow. We also present a two-dimensional hydrodynamic simulation with the Euler program, LARED-S, to reproduce the deflection. Both are in good agreement. Our results show that the large deflection angle formed in the HH 110/270 system is probably due to the ram pressure from a flow–flow collision model.« less

Effect of ambient light exposure of media and embryos on development and quality of porcine parthenogenetically activated embryos.

PubMed

Li, Rong; Liu, Ying; Pedersen, Hanne Skovsgaard; Callesen, Henrik

2015-06-01

Light exposure is a common stress factor during in vitro handling of oocytes and embryos that originates from both microscope and ambient light. In the current study, the effect of two types of ambient light (daylight and laboratory light) on porcine parthenogenetically activated (PA) embryos was tested in two experiments: (1) ambient light on medium subsequently used for embryo in vitro development; and (2) ambient light exposure on activated oocytes before in vitro development. The results from Experiment 1 showed that exposure of culture medium to both types of ambient light decreased the percentage of blastocysts that showed good morphology, only after 24 h exposure. The results from Experiment 2 revealed a reduction in both blastocyst formation and quality when activated oocytes were exposed to both types of ambient light. This effect was seen after only 1 h exposure and increased with time. In conclusion, exposure to ambient light can be harmful to embryo development, both when medium is exposed for a long period of time and, to a greater extent, when the embryo itself is exposed for >1 h. In practice, it is therefore recommended to protect both culture medium and porcine embryos against ambient light during in vitro handling in the laboratory.

Sr-90 Immobilization by Infiltration of a Ca-Citrate-PO{sub 4} Solution into the Hanford 100-N Area Vadose Zone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Szecsody, J.E.; Fruchter, J.S.; Burns, C.A.

This project was initiated to develop a strategy for infiltration of a Ca-citrate-PO{sub 4} solution in order to precipitate apatite [Ca{sub 6}(PO{sub 4}){sub 10}(OH){sub 2}] in desired locations in the vadose zone for Sr-90 remediation. Laboratory experiments have demonstrated that infiltration of a Ca-citrate-PO{sub 4} solution into sediments at low and high water saturation results in citrate biodegradation and formation of apatite. The citrate biodegradation rate was relatively uniform, in spite of the spatial variability of sediment microbial biomass, likely because of microbial transport processes that occur during solution infiltration. The precipitate was characterized as hydroxyapatite, and the Sr-90 substitutionmore » into apatite was shown to have an incorporation half-life of 5.5 to 16 months. One and two dimensional (1-D and 2-D) laboratory infiltration experiments quantified the spatial distribution of apatite that formed during solution infiltration. Slow infiltration in 2-D experiments at low water saturation show the apatite precipitate concentrated in the upper third of the infiltration zone. More rapid 1-D infiltration studies show the apatite precipitate concentrated at greater depth. (authors)« less

Cooperative action of coherent groups in broadly heterogeneous populations of interacting chemical oscillators

PubMed Central

Mikhailov, A. S.; Zanette, D. H.; Zhai, Y. M.; Kiss, I. Z.; Hudson, J. L.

2004-01-01

We present laboratory experiments on the effects of global coupling in a population of electrochemical oscillators with a multimodal frequency distribution. The experiments show that complex collective signals are generated by this system through spontaneous emergence and joint operation of coherently acting groups representing hierarchically organized resonant clusters. Numerical simulations support these experimental findings. Our results suggest that some forms of internal self-organization, characteristic for complex multiagent systems, are already possible in simple chemical systems. PMID:15263084

Inexpensive Audio Activities: Earbud-based Sound Experiments

NASA Astrophysics Data System (ADS)

Allen, Joshua; Boucher, Alex; Meggison, Dean; Hruby, Kate; Vesenka, James

2016-11-01

Inexpensive alternatives to a number of classic introductory physics sound laboratories are presented including interference phenomena, resonance conditions, and frequency shifts. These can be created using earbuds, economical supplies such as Giant Pixie Stix® wrappers, and free software available for PCs and mobile devices. We describe two interference laboratories (beat frequency and two-speaker interference) and two resonance laboratories (quarter- and half-wavelength). Lastly, a Doppler laboratory using rotating earbuds is explained. The audio signal captured by all experiments is analyzed on free spectral analysis software and many of the experiments incorporate the unifying theme of measuring the speed of sound in air.

High-Resolution Vibration-Rotation Spectroscopy of CO[subscript 2]: Understanding the Boltzmann Distribution

ERIC Educational Resources Information Center

Castle, Karen J.

2007-01-01

In this undergraduate physical chemistry laboratory experiment, students acquire a high-resolution infrared absorption spectrum of carbon dioxide and use their data to show that the rotational-vibrational state populations follow a Boltzmann distribution. Data are acquired with a mid-infrared laser source and infrared detector. Appropriate…

The effect of cohabitation of Tubifex tubifex (Oligochaeta: Tubificidae) populations on infections to Myxobolus cerebralis (Myxozoa: Myxobolidae).

PubMed

Beauchamp, Katherine A; El-Matbouli, Mansour; Gay, Melanie; Georgiadis, Marios P; Nehring, R Barry; Hedrick, Ronald P

2006-01-01

The competitive interactions between susceptible and resistant Tubifex tubifex (Oligochaeta: Tubificidae) exposed to Myxobolus cerebralis (Myxozoa: Myxobolidae) infections were investigated in two laboratory trials. Competition was assessed by the total parasite production over the course of the trials in mixed and pure cultures of M. cerebralis exposed worms, and by the genetic analyses of worms from the control and experimental groups at the beginning and end of the experiments. Mixed cultures of resistant and susceptible worms showed a 70% reduction in production of parasites released when compared with pure cultures of susceptible worms. In studies with laboratory and field-collected oligochaetes the mixed cultures at the end of the cohabitation experiments were dominated by resistant Tubifex from lineage V (HB strain) this strain of Tubifex has a competitive advantage over worms from other lineages. The results of this study suggest that certain species of Tubifex may be dead-end hosts to M. cerebralis by absorbing or inactivating the parasite and may also show greater survival compared to susceptible oligochaetes in certain whirling disease enzootic habitats.

Physical barriers formed from gelling liquids: 1. numerical design of laboratory and field experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Finsterle, S.; Moridis, G.J.; Pruess, K.

1994-01-01

The emplacement of liquids under controlled viscosity conditions is investigated by means of numerical simulations. Design calculations are performed for a laboratory experiment on a decimeter scale, and a field experiment on a meter scale. The purpose of the laboratory experiment is to study the behavior of multiple gout plumes when injected in a porous medium. The calculations for the field trial aim at designing a grout injection test from a vertical well in order to create a grout plume of a significant extent in the subsurface.

Investigating Attachment Behaviors of Cryptosporidium Parvum Oocysts Using Collision Efficiency in Laboratory Column Experiments

NASA Astrophysics Data System (ADS)

Park, Y.; Hou, L.; Atwill, R.; Packman, A. I.; Harter, T.

2009-12-01

Cryptosporidium is one of the most common enteric parasites of humans and domestic animals, and a number of outbreaks of Cryprosporidiosis, a diarrheal disease caused by Cryptosporidium have been reported worldwide. Natural porous media has been demonstrated to be an effective filter for removing Cryptosporidium parvum from contaminated water and the amount of Cryptosporidium filtered is known to be highly dependent on physical and chemical conditions of the porous media and the water. Cryptosporidium deposition in saturated porous media involves two main steps: approach and attachment. In contrast to the approach mechanisms, attachment processes have not been systematically described to predict a priori because theories that represent attachment behavior (colloid stability) such as DLVO are insufficient to explain experimental data. For this reason, attachment efficiency is calculated based on empirical data, typically experimental breakthrough curves in laboratory columns or field experiments. In this study, collision (attachment) efficiencies (α) of C. parvum oocyst were calculated to test the effect of chemical property changes on the association of oocysts with sand grains. The breakthrough curve data obtained from twelve column experiments and three models were employed to calculate single collector efficiency (η) and α. The first ten experiments were conducted by changing ionic strength and pH, and mixing with natural sediments under the same physical properties (same η). Our experiment results show that iron coating or clay/suspended solids mixture drastically enhanced oocyst deposition. The experiments also showed that increase in ionic strength and decrease in pH enhanced the attachment efficiency. However, the experiment with 100mM NaCl resulted in low attachment efficiency and the experiment with pH 8.5 showed similar attachment efficiency to the one at pH 7. Based on the results from two additional experiments with different flow velocities, it appears that attachment efficiency changes when the flow velocity changes, which contradicts CFT. The results prove that predicting attachment efficiency of C. parvum oocyst using ionic strength or pH is inappropriate when non-DLVO interactions are involved. A review of our results and comparison to existing data shows that it is challenging to accurately predict the attachment efficiency using single peak value of breakthrough curve data from geochemical information of porous media.

Development of Laboratory Seismic Exploration Experiment for Education and Demonstration

NASA Astrophysics Data System (ADS)

Kuwano, O.; Nakanishi, A.

2016-12-01

We developed a laboratory experiment to simulate a seismic refraction survey for educational purposes. The experiment is tabletop scaled experiment using the soft hydrogel as an analogue material of a layered crust. So, we can conduct the seismic exploration experiment in a laboratory or a classroom. The softness and the transparency of the gel material enable us to observe the wave propagation with our naked eyes, using the photoelastic technique. By analyzing the waveforms obtained by the image analysis of the movie of the experiment, one can estimate the velocities and the structure of the gel specimen in the same way as an actual seismic survey. We report details of the practical course and the public outreach activities using the experiment.

Pedagogical Evaluation of Remote Laboratories in eMerge Project

ERIC Educational Resources Information Center

Lang, Daniela; Mengelkamp, Christoph; Jaeger, Reinhold S.; Geoffroy, Didier; Billaud, Michel; Zimmer, Thomas

2007-01-01

This study investigates opportunities for conducting electrical engineering experiments via the Internet rather than in an actual laboratory. Eighty-four French students of electrical engineering (semester 1, 2004) at Bordeaux University 1 participated in practical courses. Half of the students performed experiments in a laboratory while the other…

A Multistep Synthesis for an Advanced Undergraduate Organic Chemistry Laboratory

ERIC Educational Resources Information Center

Chang Ji; Peters, Dennis G.

2006-01-01

Multistep syntheses are often important components of the undergraduate organic laboratory experience and a three-step synthesis of 5-(2-sulfhydrylethyl) salicylaldehyde was described. The experiment is useful as a special project for an advanced undergraduate organic chemistry laboratory course and offers opportunities for students to master a…

Child Guidance for Child Caregivers: Student Laboratory Manual.

ERIC Educational Resources Information Center

Texas Tech Univ., Lubbock. Home Economics Curriculum Center.

Designed to enhance student knowledge of and skills in child guidance in group care settings, this manual provides 50 laboratory experiences for five units. Units cover foundations and assumptions (2 laboratory experiences), developmental factors (8), indirect guidance (14), direct guidance (14), and strategies (12). Each unit includes performance…

Solvent-Free Wittig Reaction: A Green Organic Chemistry Laboratory Experiment

ERIC Educational Resources Information Center

Leung, Sam H.; Angel, Stephen A.

2004-01-01

Some Wittig reactions can be carried out by grinding the reactants in a mortar with a pestle for about 20 minutes, as per investigation. A laboratory experiment involving a solvent-free Wittig reaction that can be completed in a three-hour sophomore organic chemistry laboratory class period, are developed.

A Laboratory Course in Clinical Biochemistry Emphasizing Interest and Relevance

ERIC Educational Resources Information Center

Schwartz, Peter L.

1975-01-01

Ten laboratory experiments are described which are used in a successful clinical biochemistry laboratory course (e.g. blood alcohol, glucose tolerance, plasma triglycerides, coronary risk index, gastric analysis, vitamin C and E). Most of the experiments are performed on the students themselves using simple equipment with emphasis on useful…

Feasibility study of a zero-gravity (orbital) atmospheric cloud physics experiments laboratory

NASA Technical Reports Server (NTRS)

Hollinden, A. B.; Eaton, L. R.

1972-01-01

A feasibility and concepts study for a zero-gravity (orbital) atmospheric cloud physics experiment laboratory is discussed. The primary objective was to define a set of cloud physics experiments which will benefit from the near zero-gravity environment of an orbiting spacecraft, identify merits of this environment relative to those of groundbased laboratory facilities, and identify conceptual approaches for the accomplishment of the experiments in an orbiting spacecraft. Solicitation, classification and review of cloud physics experiments for which the advantages of a near zero-gravity environment are evident are described. Identification of experiments for potential early flight opportunities is provided. Several significant accomplishments achieved during the course of this study are presented.

Efficacy of methoprene for mosquito control in storm water catch basins

USGS Publications Warehouse

Butler, M.; LeBrun, R.A.; Ginsberg, H.S.; Gettman, A.D.

2006-01-01

This study evaluated the efficacy of methoprene, a widely used juvenile hormone mimic, formulated as 30-day slow release Altosid? pellets, at controlling mosquitoes in underground storm water drainage catch basins. Data from applications to ?-sized cement catch basins in the laboratory, field observations from treated and untreated basins, and an experiment that confined mosquito larvae in floating emergence jars in catch basins showed that methoprene effectively controlled mosquitoes for a month under field conditions and substantially longer under laboratory conditions when applied at a dose of 3.5 g pellets per average-sized catch basin.

Case-Study Investigation of Equine Maternity via PCR-RFLP: A Biochemistry Laboratory Experiment

PubMed Central

Millard, Julie T.; Chuang, Edward; Lucas, James S.; Nagy, Erzsebet E.; Davis, Griffin T.

2013-01-01

A simple and robust biochemistry laboratory experiment is described that uses restriction fragment length polymorphism (RFLP) of polymerase chain reaction (PCR) products to verify the identity of a potentially valuable horse. During the first laboratory period, students purify DNA from equine samples and amplify two loci of mitochondrial DNA. During the second laboratory period, students digest PCR products with restriction enzymes and analyze the fragment sizes through agarose gel electrophoresis. An optional step of validating DNA extracts through realtime PCR can expand the experiment to three weeks. This experiment, which has an engaging and versatile scenario, provides students with exposure to key principles and techniques of molecular biology, bioinformatics, and evolution in a forensic context. PMID:24363455

Fluorescence quantum yield measurements of fluorescent proteins: a laboratory experiment for a biochemistry or molecular biophysics laboratory course.

PubMed

Wall, Kathryn P; Dillon, Rebecca; Knowles, Michelle K

2015-01-01

Fluorescent proteins are commonly used in cell biology to assess where proteins are within a cell as a function of time and provide insight into intracellular protein function. However, the usefulness of a fluorescent protein depends directly on the quantum yield. The quantum yield relates the efficiency at which a fluorescent molecule converts absorbed photons into emitted photons and it is necessary to know for assessing what fluorescent protein is the most appropriate for a particular application. In this work, we have designed an upper-level, biochemistry laboratory experiment where students measure the fluorescence quantum yields of fluorescent proteins relative to a standard organic dye. Four fluorescent protein variants, enhanced cyan fluorescent protein (ECFP), enhanced green fluorescent protein (EGFP), mCitrine, and mCherry, were used, however the methods described are useful for the characterization of any fluorescent protein or could be expanded to fluorescent quantum yield measurements of organic dye molecules. The laboratory is designed as a guided inquiry project and takes two, 4 hr laboratory periods. During the first day students design the experiment by selecting the excitation wavelength, choosing the standard, and determining the concentration needed for the quantum yield experiment that takes place in the second laboratory period. Overall, this laboratory provides students with a guided inquiry learning experience and introduces concepts of fluorescence biophysics into a biochemistry laboratory curriculum. © 2014 The International Union of Biochemistry and Molecular Biology.

The formation of the doubly stable stratification in the Mediterranean Outflow

NASA Astrophysics Data System (ADS)

Bormans, M.; Turner, J. S.

1990-11-01

The Mediterranean Outflow as it exits from the Strait of Gibraltar can be seen as a gravity current flowing down the slope and mixing with Atlantic Water until it reaches its own density level. Typical salinity and temperature profiles through the core region of a Meddy show that the bottom of the core is colder and saltier than the top, leading to a stably stratified core with respect to double-diffusive processes. The bottom of the core is also more enriched with Mediterranean Water than the top, and this behaviour can be explained by a reduced mixing of the source water with the environment close to the rigid bottom. Although the mechanism involved is different from the actual case, we have successfully produced these doubly stable gradient in some laboratory experiments which incorporate the "filling-box" mechanism. Salt and sugar were used as laboratory analogues of temperature and salt, respectively. The laboratory experiments consisted of supplying a dense input fluid at the surface of a linearly salt stratified environment. We suggest that req, the ratio of the initial volume flux at the source to the volume flux at the equilibrium level, is an important parameter, and that in our experiments this must be in general smaller than 0.1 in order to produce a doubly stable region of salt and sugar. The most relevant experiments had a mixed sugar/salt input which is the analogue of the Mediterranean Outflow as it mixes with Atlantic Water outside the Strait of Gibraltar.

Virtually the Same: A Comparison of STEM Students' Content Knowledge, Course Performance, and Motivation to Learn in Virtual and Face-to-Face Introductory Biology Laboratories. Research and Teaching

ERIC Educational Resources Information Center

Reece, Amber J.; Butler, Malcolm B.

2017-01-01

Biology I is a required course for many science, technology, engineering, and mathematics (STEM) majors and is often their first college-level laboratory experience. The replacement of the traditional face-to-face laboratory experience with virtual laboratories could influence students' content knowledge, motivation to learn biology, and overall…

Zero-gravity cloud physics laboratory: Candidate experiments definition and preliminary concept studies

NASA Technical Reports Server (NTRS)

Eaton, L. R.; Greco, R. V.; Hollinden, A. B.

1973-01-01

The candidate definition studies on the zero-g cloud physics laboratory are covered. This laboratory will be an independent self-contained shuttle sortie payload. Several critical technology areas have been identified and studied to assure proper consideration in terms of engineering requirements for the final design. Areas include chambers, gas and particle generators, environmental controls, motion controls, change controls, observational techniques, and composition controls. This unique laboratory will allow studies to be performed without mechanical, aerodynamics, electrical, or other type techniques to support the object under study. This report also covers the candidate experiment definitions, chambers and experiment classes, laboratory concepts and plans, special supporting studies, early flight opportunities and payload planning data for overall shuttle payload requirements assessments.

Experimenting with Impacts in a Conceptual Physics or Descriptive Astronomy Laboratory

ERIC Educational Resources Information Center

LoPresto, Michael C.

2016-01-01

What follows is a description of the procedure for and results of a simple experiment on the formation of impact craters designed for the laboratory portions of lower mathematical-level general education science courses such as conceptual physics or descriptive astronomy. The experiment provides necessary experience with data collection and…

Millikan's Oil-Drop Experiment as a Remotely Controlled Laboratory

ERIC Educational Resources Information Center

Eckert, Bodo; Grober, Sebastian; Vetter, Martin; Jodl, Hans-Jorg

2012-01-01

The Millikan oil-drop experiment, to determine the elementary electrical charge e and the quantization of charge Q = n [middle dot] e, is an essential experiment in physics teaching but it is hardly performed in class for several reasons. Therefore, we offer this experiment as a remotely controlled laboratory (RCL). We describe the interactivity…

Responses to Anomalous Data Obtained from Repeatable Experiments in the Laboratory

ERIC Educational Resources Information Center

Lin, Jer-Yann

2007-01-01

The purpose of this study was to investigate the possible responses to anomalous data obtained from experiments that are repeatable by carrying out additional or alternative experiments in the laboratory. Based on an analysis of responses from scientists to anomalous data taken from identification experiments on the Vinland Map, it was assumed…

Passive electrical monitoring and localization of fluid leakages from wells

NASA Astrophysics Data System (ADS)

Revil, A.; Mao, D.; Haas, A. K.; Karaoulis, M.; Frash, L.

2015-02-01

Electrokinetic phenomena are a class of cross-coupling phenomena involving the relative displacement between the pore water (together with the electrical diffuse layer) with respect to the solid phase of a porous material. We demonstrate that electrical fields of electrokinetic nature can be associated with fluid leakages from wells. These leakages can be remotely monitored and the resulting signals used to localize their causative source distribution both in the laboratory and in field conditions. The first laboratory experiment (Experiment #1) shows how these electrical fields can be recorded at the surface of a cement block during the leakage of a brine from a well. The measurements were performed with a research-grade medical electroencephalograph and were inverted using a genetic algorithm to localize the causative source of electrical current and therefore, localize the leak in the block. Two snapshots of electrical signals were used to show how the leak evolved over time. The second experiment (Experiment #2) was performed to see if we could localize a pulse water injection from a shallow well in field conditions in the case of a heterogeneous subsurface. We used the same equipment as in Experiment #1 and processed the data with a trend removal algorithm, picking the amplitude from 24 receiver channels just after the water injection. The amplitude of the electric signals changed from the background level indicating that a volume of water was indeed flowing inside the well into the surrounding soil and then along the well. We used a least-square inversion algorithm to invert a snapshot of the electrical potential data at the injection time to localize the source of the self-potential signals. The inversion results show positive potential anomalies in the vicinity of the well. For both experiments, forward numerical simulations of the problem using a finite element package were performed in order to assess the underlying physics of the causative source of the observed electrical potential anomalies and how they are related to the flow of the water phase.

Perchlorate radiolysis on Mars and the origin of martian soil reactivity.

PubMed

Quinn, Richard C; Martucci, Hana F H; Miller, Stephanie R; Bryson, Charles E; Grunthaner, Frank J; Grunthaner, Paula J

2013-06-01

Results from the Viking biology experiments indicate the presence of reactive oxidants in martian soils that have previously been attributed to peroxide and superoxide. Instruments on the Mars Phoenix Lander and the Mars Science Laboratory detected perchlorate in martian soil, which is nonreactive under the conditions of the Viking biology experiments. We show that calcium perchlorate exposed to gamma rays decomposes in a CO2 atmosphere to form hypochlorite (ClO(-)), trapped oxygen (O2), and chlorine dioxide (ClO2). Our results show that the release of trapped O2 (g) from radiation-damaged perchlorate salts and the reaction of ClO(-) with amino acids that were added to the martian soils can explain the results of the Viking biology experiments. We conclude that neither hydrogen peroxide nor superoxide is required to explain the results of the Viking biology experiments.

Atmospheric microphysical experiments on an orbital platform

NASA Technical Reports Server (NTRS)

Eaton, L. R.

1974-01-01

The Zero-Gravity Atmospheric Cloud Physics Laboratory is a Shuttle/Spacelab payload which will be capable of performing a large range of microphysics experiments. This facility will complement terrestrial cloud physics research by allowing many experiments to be performed which cannot be accomplished within the confines of a terrestrial laboratory. This paper reviews the general Cloud Physics Laboratory concept and the experiment scope. The experimental constraints are given along with details of the proposed equipment. Examples of appropriate experiments range from three-dimensional simulation of the earth and planetary atmosphere and of ocean circulation to cloud electrification processes and the effects of atmospheric pollution materials on microphysical processes.

Evaluation of the Use of Remote Laboratories for Secondary School Science Education

NASA Astrophysics Data System (ADS)

Lowe, David; Newcombe, Peter; Stumpers, Ben

2013-06-01

Laboratory experimentation is generally considered central to science-based education. Allowing students to "experience" science through various forms of carefully designed practical work, including experimentation, is often claimed to support their learning and motivate their engagement while fulfilling specific curriculum requirements. However, logistical constraints (most especially related to funding) place significant limitations on the ability of schools to provide and maintain high-quality science laboratory experiences and equipment. One potential solution that has recently been the subject of growing interest is the use of remotely accessible laboratories to either supplant, or more commonly to supplement, conventional hands-on laboratories. Remote laboratories allow students and teachers to use high-speed networks, coupled with cameras, sensors, and controllers, to carry out experiments on real physical laboratory apparatus that is located remotely from the student. Research has shown that when used appropriately this can bring a range of potential benefits, including the ability to share resources across multiple institutions, support access to facilities that would otherwise be inaccessible for cost or technical reasons, and provide augmentation of the experimental experience. Whilst there has been considerable work on evaluating the use of remote laboratories within tertiary education, consideration of their role within secondary school science education is much more limited. This paper describes trials of the use of remote laboratories within secondary schools, reporting on the student and teacher reactions to their interactions with the laboratories. The paper concludes that remote laboratories can be highly beneficial, but considerable care must be taken to ensure that their design and delivery address a number of critical issues identified in this paper.

Modular space station phase B extension preliminary system design. Volume 3: Experiment analyses

NASA Technical Reports Server (NTRS)

Wengrow, G. L.; Lillenas, A. N.

1972-01-01

Experiment analysis tasks performed during program definition study are described. Experiment accommodation and scheduling, and defining and implementing the laboratory evolution are discussed. The general purpose laboratory requirements and concepts are defined, and supplemental studies are reported.

Freeze Drying of Fruits and Vegetables: A Laboratory Experiment.

ERIC Educational Resources Information Center

Noble, Richard D.

1979-01-01

Describes a laboratory experiment for freeze-drying fruits and vegetables which aims to expose college students to the principles of drying and simultaneous heat and mass transfer. The experimental apparatus, procedure of the experiment, and data analysis are also included. (HM)

Atmospheric-like rotating annulus experiment: gravity wave emission from baroclinic jets

NASA Astrophysics Data System (ADS)

Rodda, Costanza; Borcia, Ion; Harlander, Uwe

2017-04-01

Large-scale balanced flows can spontaneously radiate meso-scale inertia-gravity waves (IGWs) and are thus in fact unbalanced. While flow-dependent parameterizations for the radiation of IGWs from orographic and convective sources do exist, the situation is less developed for spontaneously emitted IGWs. Observations identify increased IGW activity in the vicinity of jet exit regions. A direct interpretation of those based on geostrophic adjustment might be tempting. However, directly applying this concept to the parameterization of spontaneous imbalance is difficult since the dynamics itself is continuously re-establishing an unbalanced flow which then sheds imbalances by GW radiation. Examining spontaneous IGW emission in the atmosphere and validating parameterization schemes confronts the scientist with particular challenges. Due to its extreme complexity, GW emission will always be embedded in the interaction of a multitude of interdependent processes, many of which are hardly detectable from analysis or campaign data. The benefits of repeated and more detailed measurements, while representing the only source of information about the real atmosphere, are limited by the non-repeatability of an atmospheric situation. The same event never occurs twice. This argues for complementary laboratory experiments, which can provide a more focused dialogue between experiment and theory. Indeed, life cycles are also examined in rotating- annulus laboratory experiments. Thus, these experiments might form a useful empirical benchmark for theoretical and modelling work that is also independent of any sort of subgrid model. In addition, the more direct correspondence between experimental and model data and the data reproducibility makes lab experiments a powerful testbed for parameterizations. Joint laboratory experiment and numerical simulation have been conducted. The comparison between the data obtained from the experiment and the numerical simulations shows a very good agreement for the large scale baroclinic wave regime. Moreover, in both cases a clear signal of horizontal divergence, embedded in the baroclinic wave front, appears suggesting IGWs emission.

Coarsening Experiment Being Prepared for Flight

NASA Technical Reports Server (NTRS)

Hickman, J. Mark

2001-01-01

The Coarsening in Solid-Liquid Mixtures-2 (CSLM-2) experiment is a materials science space flight experiment whose purpose is to investigate the kinetics of competitive particle growth within a liquid matrix. During coarsening, small particles shrink by losing atoms to larger particles, causing the larger particles to grow. In this experiment, solid particles of tin will grow (coarsen) within a liquid lead-tin eutectic matrix. The preceding figures show the coarsening of tin particles in a lead-tin eutectic as a function of time. By conducting this experiment in a microgravity environment, we can study a greater range of solid volume fractions, and the effects of sedimentation present in terrestrial experiments will be negligible. The CSLM-2 experiment is slated to fly onboard the International Space Station. The experiment will be run in the Microgravity Science Glovebox installed in the U.S. Laboratory module.

Mid- and far-infrared spectroscopic studies of the influence of temperature, ultraviolet photolysis and ion irradiation on cosmic-type ices.

PubMed

Moore, M H; Hudson, R L; Gerakines, P A

2001-03-15

Infrared (IR) studies of laboratory ices can provide information on the evolution of cosmic-type ices as a function of different simulated space environments involving thermal, ultraviolet (UV), or ion processing. Laboratory radiation experiments can lead to the formation of complex organic molecules. However, because of our lack of knowledge about UV photon and ion fluxes, and exposure lifetimes, it is not certain how well our simulations represent space conditions. Appropriate laboratory experiments are also limited by the absence of knowledge about the composition, density, and temperature of ices in different regions of space. Our current understanding of expected doses due to UV photons and cosmic rays is summarized here, along with an inventory of condensed-phase molecules identified on outer solar system surfaces, comets and interstellar grains. Far-IR spectra of thermally cycled H2O are discussed since these results reflect the dramatic difference between the amorphous and crystalline phases of H2O ice, the most dominant condensed-phase molecule in cosmic ices. A comparison of mid-IR spectra of products in proton-irradiated and UV-photolyzed ices shows that few differences are observed for these two forms of processing for the simple binary mixtures studied to date. IR identification of radiation products and experiments to determine production rates of new molecules in ices during processing are discussed. A new technique for measuring intrinsic IR band strengths of several unstable molecules is presented. An example of our laboratory results applied to Europa observations is included.

Laboratory Modelling of Volcano Plumbing Systems: a review

NASA Astrophysics Data System (ADS)

Galland, Olivier; Holohan, Eoghan P.; van Wyk de Vries, Benjamin; Burchardt, Steffi

2015-04-01

Earth scientists have, since the XIX century, tried to replicate or model geological processes in controlled laboratory experiments. In particular, laboratory modelling has been used study the development of volcanic plumbing systems, which sets the stage for volcanic eruptions. Volcanic plumbing systems involve complex processes that act at length scales of microns to thousands of kilometres and at time scales from milliseconds to billions of years, and laboratory models appear very suitable to address them. This contribution reviews laboratory models dedicated to study the dynamics of volcano plumbing systems (Galland et al., Accepted). The foundation of laboratory models is the choice of relevant model materials, both for rock and magma. We outline a broad range of suitable model materials used in the literature. These materials exhibit very diverse rheological behaviours, so their careful choice is a crucial first step for the proper experiment design. The second step is model scaling, which successively calls upon: (1) the principle of dimensional analysis, and (2) the principle of similarity. The dimensional analysis aims to identify the dimensionless physical parameters that govern the underlying processes. The principle of similarity states that "a laboratory model is equivalent to his geological analogue if the dimensionless parameters identified in the dimensional analysis are identical, even if the values of the governing dimensional parameters differ greatly" (Barenblatt, 2003). The application of these two steps ensures a solid understanding and geological relevance of the laboratory models. In addition, this procedure shows that laboratory models are not designed to exactly mimic a given geological system, but to understand underlying generic processes, either individually or in combination, and to identify or demonstrate physical laws that govern these processes. From this perspective, we review the numerous applications of laboratory models to understand the distinct key features of volcanic plumbing systems: dykes, cone sheets, sills, laccoliths, caldera-related structures, ground deformation, magma/fault interactions, and explosive vents. Barenblatt, G.I., 2003. Scaling. Cambridge University Press, Cambridge. Galland, O., Holohan, E.P., van Wyk de Vries, B., Burchardt, S., Accepted. Laboratory modelling of volcanic plumbing systems: A review, in: Breitkreuz, C., Rocchi, S. (Eds.), Laccoliths, sills and dykes: Physical geology of shallow level magmatic systems. Springer.

Circular Dichroism Spectroscopy: Enhancing a Traditional Undergraduate Biochemistry Laboratory Experience

ERIC Educational Resources Information Center

Lewis, Russell L.; Seal, Erin L.; Lorts, Aimee R.; Stewart, Amanda L.

2017-01-01

The undergraduate biochemistry laboratory curriculum is designed to provide students with experience in protein isolation and purification protocols as well as various data analysis techniques, which enhance the biochemistry lecture course and give students a broad range of tools upon which to build in graduate level laboratories or once they…

An Upper Level Laboratory Course of Integrated Experiments

ERIC Educational Resources Information Center

Rose, T. L.; Seyse, R. J.

1974-01-01

Discusses the development of a one-year laboratory course in an effort to provide a link between traditional laboratories devoted to a single area of chemistry and the total involvement of a single narrow research project. Included are outlines of 32-hour lectures and 11 experiments performed in the integrated course. (CC)

A General Chemistry Laboratory Course Designed for Student Discussion

ERIC Educational Resources Information Center

Obenland, Carrie A.; Kincaid, Kristi; Hutchinson, John S.

2014-01-01

We report a study of the general chemistry laboratory course at one university over four years. We found that when taught as a traditional laboratory course, lab experiences do not encourage students to deepen their understanding of chemical concepts. Although the lab instructor emphasized that the lab experiences were designed to enhance…

How Efficient is a Laboratory Burner in Heating Water?

ERIC Educational Resources Information Center

Jansen, Michael P.

1997-01-01

Describes an experiment in which chemistry students determine the efficiency of a laboratory burner used to heat water. The reaction is assumed to be the complete combustion of methane, CH4. The experiment is appropriate for secondary school chemistry students familiar with heats of reaction and simple calorimetry. Contains pre-laboratory and…

Measuring Stellar Temperatures: An Astrophysical Laboratory for Undergraduate Students

ERIC Educational Resources Information Center

Cenadelli, D.; Zeni, M.

2008-01-01

While astrophysics is a fascinating subject, it hardly lends itself to laboratory experiences accessible to undergraduate students. In this paper, we describe a feasible astrophysical laboratory experience in which the students are guided to take several stellar spectra, using a telescope, a spectrograph and a CCD camera, and perform a full data…

Microcomputers for Young Children: Procedures and Practices in the Laboratory Classroom.

ERIC Educational Resources Information Center

Baker, Betty Ruth

These guidelines are designed to give preservice teachers information to use in selecting techniques and planning learning experiences for young children in the microcomputer laboratory. The main purpose of this laboratory experience is for children to develop computer awareness/literacy and keyboard knowledge, and to improve skills in following…

Optical closure experiments for biomass smoke aerosols

Treesearch

L. A. Mack; E. J. T. Levin; S. M. Kreidenweis; D. Obrist; H. Moosmuller; K. A. Lewis; W. P. Arnott; G. R. McMeeking; A. P. Sullivan; C. E. Wold; W.-M. Hao; J. L. Collett; W. C. Malm

2010-01-01

A series of laboratory experiments at the Fire Laboratory at Missoula (FLAME) investigated chemical, physical, and optical properties of fresh smoke samples from combustion of wildland fuels that are burned annually in the western and southeastern US The burns were conducted in the combustion chamber of the US Forest Service Fire Sciences Laboratory in Missoula,...

Combustion and Energy Transfer Experiments: A Laboratory Model for Linking Core Concepts across the Science Curriculum

ERIC Educational Resources Information Center

Barreto, Jose C.; Dubetz, Terry A.; Schmidt, Diane L.; Isern, Sharon; Beatty, Thomas; Brown, David W.; Gillman, Edward; Alberte, Randall S.; Egiebor, Nosa O.

2007-01-01

Core concepts can be integrated throughout lower-division science and engineering courses by using a series of related, cross-referenced laboratory experiments. Starting with butane combustion in chemistry, the authors expanded the underlying core concepts of energy transfer into laboratories designed for biology, physics, and engineering. This…

Real-Time Internet Mediated Laboratory Experiments for Distance Education Students.

ERIC Educational Resources Information Center

Lemckert, Charles; Florance, John

2002-01-01

Discusses the demand for distance education opportunities in engineering and science and considers delivery methods for theoretical content and for laboratory work. Explains the Real-Time Internet Mediated Laboratory Experiments (RTIMLE) that use the World Wide Web, and suggests that RTIMLE may be most appropriate for students who already have…

An Analysis of High School Students' Perceptions and Academic Performance in Laboratory Experiences

ERIC Educational Resources Information Center

Mirchin, Robert Douglas

2012-01-01

This research study is an investigation of student-laboratory (i.e., lab) learning based on students' perceptions of experiences using questionnaire data and evidence of their science-laboratory performance based on paper-and-pencil assessments using Maryland-mandated criteria, Montgomery County Public Schools (MCPS) criteria, and published…

Investigating Affective Experiences in the Undergraduate Chemistry Laboratory: Students' Perceptions of Control and Responsibility

ERIC Educational Resources Information Center

Galloway, Kelli R.; Malakpa, Zoebedeh; Bretz, Stacey Lowery

2016-01-01

Meaningful learning requires the integration of cognitive and affective learning with the psychomotor, i.e., hands-on learning. The undergraduate chemistry laboratory is an ideal place for meaningful learning to occur. However, accurately characterizing students' affective experiences in the chemistry laboratory can be a very difficult task. While…

Laboratory Connections: Resistance Probes in the Science Laboratory Part II. Interfacing a Light Sensitive Device.

ERIC Educational Resources Information Center

Powers, Michael H.

1987-01-01

Discusses various types of transducers and explains the use of a photoresistor in sensing light. Describes various hardware and software combinations which can be used with photoresistors in science laboratory experiments. Presents general applications of this instrument in light-meter, solarimeter, and colorimeter experiments. (TW)

Elementary and Advanced Computer Projects for the Physics Classroom and Laboratory

DTIC Science & Technology

1992-12-01

are SPF/PC, MS Word, n3, Symphony, Mathematics, and FORTRAN. The authors’ programs assist data analysis in particular laboratory experiments and make...assist data analysis in particular laboratory experiments and make use of the Monte Carlo and other numerical techniques in computer simulation and...the language of science and engineering in industry and government laboratories (alth..4h C is becoming a powerful competitor ). RM/FORTRAN (cost $400

Introduction of optical tweezers in advanced physics laboratory

NASA Astrophysics Data System (ADS)

Wang, Gang

2017-08-01

Laboratories are an essential part of undergraduate optoelectronics and photonics education. Of particular interest are the sequence of laboratories which offer students meaningful research experience within a reasonable time-frame limited by regular laboratory hours. We will present our introduction of optical tweezers into the upper-level physics laboratory. We developed the sequence of experiments in the Advanced Lab to offer students sufficient freedom to explore, rather than simply setting up a demonstration following certain recipes. We will also present its impact on our current curriculum of optoelectronics concentration within the physics program.

The Sixth SeaWiFS/SIMBIOS Intercalibration Round-Robin Experiment (SIRREX-6)

NASA Technical Reports Server (NTRS)

Riley, Thomas; Bailey, Sean

1998-01-01

For the sixth Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) Intercalibration Round-Robin Experiment (SIRREX-6), NASA personnel carried the same four Satlantic in-water radiometers to nine separate laboratories and calibrated them. Two of the sensors were seven-channel radiance heads and two were seven-channel irradiance heads. The calibration and data reduction procedures used at each site followed that laboratory's normal procedures. The reference lamps normally used for the calibration of these types of instruments by the various laboratories were also used for this experiment. NASA personnel processed the data to produce calibration parameters from the various laboratories

Synthesis and Catalytic Activity of Ruthenium-Indenylidene Complexes for Olefin Metathesis: Microscale Experiments for the Undergraduate Inorganic or Organometallic Laboratories

ERIC Educational Resources Information Center

Pappenfus, Ted M.; Hermanson, David L.; Ekerholm, Daniel P.; Lilliquist, Stacie L.; Mekoli, Megan L.

2007-01-01

A series of experiments for undergraduate laboratory courses (e.g., inorganic, organometallic or advanced organic) have been developed. These experiments focus on understanding the design and catalytic activity of ruthenium-indenylidene complexes for olefin metathesis. Included in the experiments are the syntheses of two ruthenium-indenylidene…

Mentoring undergraduate students in neuroscience research: a model system at baldwin-wallace college.

PubMed

Mickley, G Andrew; Kenmuir, Cynthia; Remmers-Roeber, Dawn

2003-01-01

As neuroscience research and discovery undergoes phenomenal growth worldwide, undergraduate students are seeking complete laboratory experiences that go beyond the classic classroom curriculum and provide mentoring in all aspects of science. Stock, in-class, laboratory experiences with known outcomes are less desirable than discovery-based projects in which students become full partners with faculty in the design, conduct and documentation of experiments that find their way into the peer-reviewed literature. The challenges of providing such experiences in the context of a primarily undergraduate institution (PUI) can be daunting. Faculty teaching loads are high, and student time is spread over a variety of courses and co-curricular activities. In this context, undergraduates are often reluctant, or ill equipped, to take individual initiative to generate and perform empirical studies. They are more likely to become involved in a sustained, faculty-initiated research program. This paper describes such a program at Baldwin-Wallace College. Students frequently start their laboratory activities in the freshman or sophomore year and enter into a system of faculty and peer mentoring that leads them to experience all aspects of the research enterprise. Students begin with learning basic laboratory tasks and may eventually achieve the status of "Senior Laboratory Associate" (SLA). SLAs become involved in laboratory management, training of less-experienced students, manuscript preparation, and grant proposal writing. The system described here provides a structured, but encouraging, community in which talented undergraduates can develop and mature as they are mentored in the context of a modern neuroscience laboratory. Retention is very good - as most students continue their work in the laboratory for 2-3 years. Student self-reports regarding their growth and satisfaction with the experiences in the laboratory have been excellent and our neuroscience students' acceptance rate in graduate, medical and veterinary schools has been well above the College average. The system also fosters faculty productivity and satisfaction in the context of the typical challenges of conducting research at a PUI.

EDITORIAL: Interrelationship between plasma phenomena in the laboratory and in space

NASA Astrophysics Data System (ADS)

Koepke, Mark

2008-07-01

The premise of investigating basic plasma phenomena relevant to space is that an alliance exists between both basic plasma physicists, using theory, computer modelling and laboratory experiments, and space science experimenters, using different instruments, either flown on different spacecraft in various orbits or stationed on the ground. The intent of this special issue on interrelated phenomena in laboratory and space plasmas is to promote the interpretation of scientific results in a broader context by sharing data, methods, knowledge, perspectives, and reasoning within this alliance. The desired outcomes are practical theories, predictive models, and credible interpretations based on the findings and expertise available. Laboratory-experiment papers that explicitly address a specific space mission or a specific manifestation of a space-plasma phenomenon, space-observation papers that explicitly address a specific laboratory experiment or a specific laboratory result, and theory or modelling papers that explicitly address a connection between both laboratory and space investigations were encouraged. Attention was given to the utility of the references for readers who seek further background, examples, and details. With the advent of instrumented spacecraft, the observation of waves (fluctuations), wind (flows), and weather (dynamics) in space plasmas was approached within the framework provided by theory with intuition provided by the laboratory experiments. Ideas on parallel electric field, magnetic topology, inhomogeneity, and anisotropy have been refined substantially by laboratory experiments. Satellite and rocket observations, theory and simulations, and laboratory experiments have contributed to the revelation of a complex set of processes affecting the accelerations of electrons and ions in the geospace plasma. The processes range from meso-scale of several thousands of kilometers to micro-scale of a few meters to kilometers. Papers included in this special issue serve to synthesise our current understanding of processes related to the coupling and feedback at disparate scales. Categories of topics included here are (1) ionospheric physics and (2) Alfvén-wave physics, both of which are related to the particle acceleration responsible for auroral displays, (3) whistler-mode triggering mechanism, which is relevant to radiation-belt dynamics, (4) plasmoid encountering a barrier, which has applications throughout the realm of space and astrophysical plasmas, and (5) laboratory investigations of the entire magnetosphere or the plasma surrounding the magnetosphere. The papers are ordered from processes that take place nearest the Earth to processes that take place at increasing distances from Earth. Many advances in understanding space plasma phenomena have been linked to insight derived from theoretical modeling and/or laboratory experiments. Observations from space-borne instruments are typically interpreted using theoretical models developed to predict the properties and dynamics of space and astrophysical plasmas. The usefulness of customized laboratory experiments for providing confirmation of theory by identifying, isolating, and studying physical phenomena efficiently, quickly, and economically has been demonstrated in the past. The benefits of laboratory experiments to investigating space-plasma physics are their reproducibility, controllability, diagnosability, reconfigurability, and affordability compared to a satellite mission or rocket campaign. Certainly, the plasma being investigated in a laboratory device is quite different from that being measured by a spaceborne instrument; nevertheless, laboratory experiments discover unexpected phenomena, benchmark theoretical models, develop physical insight, establish observational signatures, and pioneer diagnostic techniques. Explicit reference to such beneficial laboratory contributions is occasionally left out of the citations in the space-physics literature in favor of theory-paper counterparts and, thus, the scientific support that laboratory results can provide to the development of space-relevant theoretical models is often under-recognized. It is unrealistic to expect the dimensional parameters corresponding to space plasma to be matchable in the laboratory. However, a laboratory experiment is considered well designed if the subset of parameters relevant to a specific process shares the same phenomenological regime as the subset of analogous space parameters, even if less important parameters are mismatched. Regime boundaries are assigned by normalizing a dimensional parameter to an appropriate reference or scale value to make it dimensionless and noting the values at which transitions occur in the physical behavior or approximations. An example of matching regimes for cold-plasma waves is finding a 45° diagonal line on the log--log CMA diagram along which lie both a laboratory-observed wave and a space-observed wave. In such a circumstance, a space plasma and a lab plasma will support the same kind of modes if the dimensionless parameters are scaled properly (Bellan 2006 Fundamentals of Plasma Physics (Cambridge: Cambridge University Press) p 227). The plasma source, configuration geometry, and boundary conditions associated with a specific laboratory experiment are characteristic elements that affect the plasma and plasma processes that are being investigated. Space plasma is not exempt from an analogous set of constraining factors that likewise influence the phenomena that occur. Typically, each morphologically distinct region of space has associated with it plasma that is unique by virtue of the various mechanisms responsible for the plasma's presence there, as if the plasma were produced by a unique source. Boundary effects that typically constrain the possible parameter values to lie within one or more restricted ranges are inescapable in laboratory plasma. The goal of a laboratory experiment is to examine the relevant physics within these ranges and extrapolate the results to space conditions that may or may not be subject to any restrictions on the values of the plasma parameters. The interrelationship between laboratory and space plasma experiments has been cultivated at a low level and the potential scientific benefit in this area has yet to be realized. The few but excellent examples of joint papers, joint experiments, and directly relevant cross-disciplinary citations are a direct result of the emphasis placed on this interrelationship two decades ago. Building on this special issue Plasma Physics and Controlled Fusion plans to create a dedicated webpage to highlight papers directly relevant to this field published either in the recent past or in the future. It is hoped that this resource will appeal to the readership in the laboratory-experiment and space-plasma communities and improve the cross-fertilization between them.

Hidden in the light: Magnetically induced afterglow from trapped chameleon fields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gies, Holger; Mota, David F.; Shaw, Douglas J.

2008-01-15

We propose an afterglow phenomenon as a unique trace of chameleon fields in optical experiments. The vacuum interaction of a laser pulse with a magnetic field can lead to a production and subsequent trapping of chameleons in the vacuum chamber, owing to their mass dependence on the ambient matter density. Magnetically induced reconversion of the trapped chameleons into photons creates an afterglow over macroscopic timescales that can conveniently be searched for by current optical experiments. We show that the chameleon parameter range accessible to available laboratory technology is comparable to scales familiar from astrophysical stellar energy-loss arguments. We analyze quantitativelymore » the afterglow properties for various experimental scenarios and discuss the role of potential background and systematic effects. We conclude that afterglow searches represent an ideal tool to aim at the production and detection of cosmologically relevant scalar fields in the laboratory.« less

Bullet Impact Safety Study of PBX-9502

NASA Astrophysics Data System (ADS)

Ferranti, Louis

2013-06-01

A new small arms capability for performing bullet impact testing into energetic materials has recently been activated at Lawrence Livermore National Laboratory located in the High Explosives Applications Facility (HEAF). The initial capability includes 0.223, 0.30, and 0.50 testing calibers with the flexibility to add other barrels in the near future. An initial test series has been performed using the 0.50 caliber barrel shooting bullets into targets using the TATB based explosive PBX-9502 and shows an expected non-violent reaction. Future experiments to evaluate the safety of new explosive formulations to bullet impact are planned. A highlight of the new capability along with discussion of the initial experiments to date will be presented including future areas of research. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Extension of Gutenberg-Richter distribution to MW -1.3, no lower limit in sight

NASA Astrophysics Data System (ADS)

Boettcher, Margaret S.; McGarr, A.; Johnston, Malcolm

2009-05-01

With twelve years of seismic data from TauTona Gold Mine, South Africa, we show that mining-induced earthquakes follow the Gutenberg-Richter relation with no scale break down to the completeness level of the catalog, at moment magnitude M W -1.3. Events recorded during relatively quiet hours in 2006 indicate that catalog detection limitations, not earthquake source physics, controlled the previously reported minimum magnitude in this mine. Within the Natural Earthquake Laboratory in South African Mines (NELSAM) experiment's dense seismic array, earthquakes that exhibit shear failure at magnitudes as small as M W -3.9 are observed, but we find no evidence that M W -3.9 represents the minimum magnitude. In contrast to previous work, our results imply small nucleation zones and that earthquake processes in the mine can readily be scaled to those in either laboratory experiments or natural faults.

Anti-ulcer and ulcer healing potentials of Musa sapientum peel extract in the laboratory rodents.

PubMed

Onasanwo, Samuel Adetunji; Emikpe, Benjamin Obukowho; Ajah, Austin Azubuike; Elufioye, Taiwo Olayemi

2013-07-01

This study investigated the anti-ulcer and ulcer healing potentials of the methanol extract of Musa sapientum peel in the laboratory rats. Methanol extract of the peels on Musa sapientum (MEMS) was evaluated for its anti-ulcer using alcohol-induced, aspirin-induced, and pyloric ligation-induced models, and for its ulcer healing employing acetic acid-induced ulcer models in rats. The findings from this experiment showed that MEMS (50, 100 and 200 mg/kg, b.w.) anti-ulcer and ulcer healing activity (P ≤ 0.05) is dose-dependent. Also, MEMS exhibited healing of the ulcer base in all the treated groups when compared with the control group. The outcomes of this experiment revealed that the anti-ulcer effect of MEMS may be due to its anti-secretory and cyto-protective activity. The healing of the ulcer base might not be unconnected with basic fibroblast growth factors responsible for epithelial regeneration.

Bioremediation of aircraft deicing fluids (glycol) at airports. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gallagher, D.W.

1998-09-01

This report describes the work done to determine the effectiveness of various aerobic bioremediation techniques for reducing the biochemical oxygen demand (BOD) of aircraft deicing fluid runoff. Primary emphasis has been placed on laboratory and field demonstrations of bioremediation systems using various combinations of inocula (bacteria), nutrient mixes, enzyme mixes, and ultrasonic stimulation. Laboratory experiments with a variety of inocula and nutrients together with enzymes and ultrasound are demonstrated showing the importance of the appropriate bacteria and nutrient mix in bioaugmentation. The appropriate mix was shown to significantly influence biodegradation. Deicing solutions were routinely reduced to acceptable BOD levels formore » effluent discharge in 3 days or less. In the field experiment, a special dual-tank bioreactor system was developed to demonstrate a pilot small-scale system. Experimental operation of this system confirmed that a 3-day or less remediation cycle was possible during the winter season.« less

Developed turbulence and nonlinear amplification of magnetic fields in laboratory and astrophysical plasmas

DOE PAGES

Meinecke, Jena; Tzeferacos, Petros; Bell, Anthony; ...

2015-06-22

The visible matter in the universe is turbulent and magnetized. Turbulence in galaxy clusters is produced by mergers and by jets of the central galaxies and believed responsible for the amplification of magnetic fields. We report on experiments looking at the collision of two laser-produced plasma clouds, mimicking, in the laboratory, a cluster merger event. By measuring the spectrum of the density fluctuations, we infer developed, Kolmogorov-like turbulence. From spectral line broadening, we estimate a level of turbulence consistent with turbulent heating balancing radiative cooling, as it likely does in galaxy clusters. We show that the magnetic field is amplifiedmore » by turbulent motions, reaching a nonlinear regime that is a precursor to turbulent dynamo. Thus, our experiment provides a promising platform for understanding the structure of turbulence and the amplification of magnetic fields in the universe.« less

Developed turbulence and nonlinear amplification of magnetic fields in laboratory and astrophysical plasmas

PubMed Central

Meinecke, Jena; Tzeferacos, Petros; Bell, Anthony; Bingham, Robert; Clarke, Robert; Churazov, Eugene; Crowston, Robert; Doyle, Hugo; Drake, R. Paul; Heathcote, Robert; Koenig, Michel; Kuramitsu, Yasuhiro; Kuranz, Carolyn; Lee, Dongwook; MacDonald, Michael; Murphy, Christopher; Notley, Margaret; Park, Hye-Sook; Pelka, Alexander; Ravasio, Alessandra; Reville, Brian; Sakawa, Youichi; Wan, Willow; Woolsey, Nigel; Yurchak, Roman; Miniati, Francesco; Schekochihin, Alexander; Lamb, Don; Gregori, Gianluca

2015-01-01

The visible matter in the universe is turbulent and magnetized. Turbulence in galaxy clusters is produced by mergers and by jets of the central galaxies and believed responsible for the amplification of magnetic fields. We report on experiments looking at the collision of two laser-produced plasma clouds, mimicking, in the laboratory, a cluster merger event. By measuring the spectrum of the density fluctuations, we infer developed, Kolmogorov-like turbulence. From spectral line broadening, we estimate a level of turbulence consistent with turbulent heating balancing radiative cooling, as it likely does in galaxy clusters. We show that the magnetic field is amplified by turbulent motions, reaching a nonlinear regime that is a precursor to turbulent dynamo. Thus, our experiment provides a promising platform for understanding the structure of turbulence and the amplification of magnetic fields in the universe. PMID:26100873

Near Field Observations of Seismicity in Volcanic Environments: A Read-Made Field Laboratory

NASA Astrophysics Data System (ADS)

Bean, C. J.; Thun, J.; Eibl, E. P. S.; Benson, P. M.; Rowley, P.; Lokmer, I.; Cauchie, L.

2017-12-01

Volcanic environments experience periods of rapid stress fluctuations and consequent seismicity. This volcano seismicity is diverse in character, spanning the range from discrete high frequency events through low-frequency earthquakes and tremor. The inter-relationships between these events appear to be controlled by edifice rheology, stress state and the presence of fluids (which help modulate the stress field). In general volcanoes are accessible to instrumentation, allowing near-field access to the seismicity at play. Here we present results from a range of field, numerical and laboratory experiments that demonstrate the controls that rheology and strain rate play on seismicity type. In particular we demonstrate the role played by internal friction angles on the initiation and evolution of seismicity, in dry weak-compliant volcanic materials. Furthermore we show the importance of near field observation in constraining details of the seismic source, in a meso-scale field setting.

Extension of Gutenberg-Richter distribution to Mw -1.3, no lower limit in sight

USGS Publications Warehouse

Boettcher, M.S.; McGarr, A.; Johnston, M.

2009-01-01

[1] With twelve years of seismic data from TauTona Gold Mine, South Africa, we show that mining-induced earthquakes follow the Gutenberg-Richter relation with no scale break down to the completeness level of the catalog, at moment magnitude Mw -1.3. Events recorded during relatively quiet hours in 2006 indicate that catalog detection limitations, not earthquake source physics, controlled the previously reported minimum magnitude in this mine. Within the Natural Earthquake Laboratory in South African Mines (NELSAM) experiment's dense seismic array, earthquakes that exhibit shear failure at magnitudes as small as Mw -3.9 are observed, but we find no evidence that Mw -3.9 represents the minimum magnitude. In contrast to previous work, our results imply small nucleation zones and that earthquake processes in the mine can readily be scaled to those in either laboratory experiments or natural faults.

The Muon $g$-$2$ Experiment at Fermilab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gohn, Wesley

A new measurement of the anomalous magnetic moment of the muon,more » $$a_{\\mu} \\equiv (g-2)/2$$, will be performed at the Fermi National Accelerator Laboratory with data taking beginning in 2017. The most recent measurement, performed at Brookhaven National Laboratory (BNL) and completed in 2001, shows a 3.5 standard deviation discrepancy with the standard model value of $$a_\\mu$$. The new measurement will accumulate 21 times the BNL statistics using upgraded magnet, detector, and storage ring systems, enabling a measurement of $$a_\\mu$$ to 140 ppb, a factor of 4 improvement in the uncertainty the previous measurement. This improvement in precision, combined with recent improvements in our understanding of the QCD contributions to the muon $g$-$2$, could provide a discrepancy from the standard model greater than 7$$\\sigma$$ if the central value is the same as that measured by the BNL experiment, which would be a clear indication of new physics.« less

The Advanced Lab Course at the University of Houston

NASA Astrophysics Data System (ADS)

Forrest, Rebecca

2009-04-01

The University of Houston Advanced Lab course is designed to help students understand the physics in classic experiments, become familiar with experimental equipment and techniques, gain experience with independent experimentation, and learn to communicate results orally and in writing. It is a two semester course, with a Lab Seminar also required during the first semester. In the Seminar class we discuss keeping a notebook and writing a laboratory report, error analysis, data fitting, and scientific ethics. The students give presentations, in pairs, on the workings and use of basic laboratory equipment. In the Lab courses students do a one week introductory experiment, followed by six two-week experiments each semester. These range from traditional experiments in modern physics to contemporary experiments with superconductivity and chaos. The students are required to keep a laboratory notebook and to write a four-page paper for each experiment in the publication style of the American Institute of Physics. This course introduces students to the experimental tools and techniques used in physics, engineering, and industry laboratories, and allows them to mature as experimentalists.

10 CFR 60.143 - Monitoring and testing waste packages.

Code of Federal Regulations, 2010 CFR

2010-01-01

... package monitoring program shall include laboratory experiments which focus on the internal condition of... the laboratory experiments. (d) The waste package monitoring program shall continue as long as...

10 CFR 60.143 - Monitoring and testing waste packages.

Code of Federal Regulations, 2011 CFR

2011-01-01

... package monitoring program shall include laboratory experiments which focus on the internal condition of... the laboratory experiments. (d) The waste package monitoring program shall continue as long as...

10 CFR 60.143 - Monitoring and testing waste packages.

Code of Federal Regulations, 2012 CFR

2012-01-01

... package monitoring program shall include laboratory experiments which focus on the internal condition of... the laboratory experiments. (d) The waste package monitoring program shall continue as long as...

10 CFR 60.143 - Monitoring and testing waste packages.

Code of Federal Regulations, 2013 CFR

2013-01-01

... package monitoring program shall include laboratory experiments which focus on the internal condition of... the laboratory experiments. (d) The waste package monitoring program shall continue as long as...

10 CFR 60.143 - Monitoring and testing waste packages.

Code of Federal Regulations, 2014 CFR

2014-01-01

... package monitoring program shall include laboratory experiments which focus on the internal condition of... the laboratory experiments. (d) The waste package monitoring program shall continue as long as...

Impact Crater Experiments for Introductory Physics and Astronomy Laboratories

ERIC Educational Resources Information Center

Claycomb, J. R.

2009-01-01

Activity-based collisional analysis is developed for introductory physics and astronomy laboratory experiments. Crushable floral foam is used to investigate the physics of projectiles undergoing completely inelastic collisions with a low-density solid forming impact craters. Simple drop experiments enable determination of the average acceleration,…

Spectroelectrochemical Sensing of Aqueous Iron: An Experiment for Analytical Chemistry

ERIC Educational Resources Information Center

Shtoyko, Tanya; Stuart, Dean; Gray, H. Neil

2007-01-01

We have designed a laboratory experiment to illustrate the use of spectroelectrochemical techniques for determination of aqueous iron. The experiment described in this article is applicable to an undergraduate laboratory course in analytical chemistry. Students are asked to fabricate spectroelectrochemical sensors, make electrochemical and optical…

Organic matter controls of iron incorporation in growing sea ice

NASA Astrophysics Data System (ADS)

Janssens, Julie; Meiners, Klaus M.; Townsend, Ashley T.; Lannuzel, Delphine

2018-03-01

This study presents the first laboratory-controlled sea-ice growth experiment conducted under trace metal clean conditions. The role played by organic matter, in the incorporation of iron (Fe) into sea ice was investigated by means of laboratory ice-growth experiments using a titanium cold-finger apparatus. Experiments were also conducted to understand the role of extracellular polymeric substances (EPS) in the enrichment of ammonium in sea ice. Sea ice was grown from several seawater solutions containing different quantities and qualities of particulate Fe (PFe), dissolved Fe (DFe) and organic matter. Sea ice and seawater were analyzed for particulate organic carbon and nitrogen, macro-nutrients, extracellular EPS, PFe and DFe, and particulate aluminium. The experiments showed that biogenic PFe is preferentially incorporated into sea ice compared to lithogenic PFe. Furthermore, sea ice grown from ultra-violet (UV) and non-UV treated seawaters exhibits contrasting incorporation rates of organic matter and Fe. Whereas the effects of UV-treatments were not always significant, we do find indications that the type or organic matter controls the enrichment of Fe in forming sea ice.. Specifically, we come to the conclusion that the incorporation of DFe is favored by the presence of organic ligands in the source solution.

Two Non Linear Dynamics Plasma Astrophysics Experiments At LANL

NASA Astrophysics Data System (ADS)

Intrator, T.; Weber, T.; Feng, Y.; Sears, J.; Smith, R. J.; Swan, H.; Hutchinson, T.; Boguski, J.; Gao, K.; Chapdelaine, L.; Dunn, J. P.

2013-12-01

Two laboratory experiments at Los Alamos National Laboratory (LANL) have been built to gain access to a wide range of fundamental plasma physics issues germane to astro, space, and fusion plasmas. The over arching theme is magnetized plasma dynamics that include currents, MHD forces and instabilities, sheared flows and shocks, along with creation and annihilation of magnetic field. The Relaxation Scaling Experiment (RSX) creates current sheets and flux ropes that exhibit fully 3D dynamics, that are observed to kink, bounce, merge and reconnect, shred, and reform in complicated ways. We show recent movies from a large detailed data set that describe the 3D magnetic structure and helicity budget of a driven and dissipative system that spontaneously self saturates a kink instability. The Magnetized Shock Experiment (MSX) uses a Field reversed configuration (FRC) that is ejected at high speed and then stagnated onto a stopping mirror field, which drives a collisionless magnetized shock. A plasmoid accelerator will also access super critical shocks at much larger Alfven Mach numbers. Unique features include access to parallel, oblique and perpendicular shocks, in regions much larger than ion gyro radius and inertial length, large magnetic and fluid Reynolds numbers, and volume for turbulence.

Usage of "Powergraph" software at laboratory lessons of "general physics" department of MEPhI

NASA Astrophysics Data System (ADS)

Klyachin, N. A.; Matronchik, A. Yu.; Khangulyan, E. V.

2017-01-01

One considers usage of "PowerGraph" software in laboratory exercise "Study of sodium spectrum" of physical experiment lessons. Togethe with the design of experiment setup, one discusses the sodium spectra digitized with computer audio chip. Usage of "PowerGraph" software in laboratory experiment "Study of sodium spectrum" allows an efficient visualization of the sodium spectrum and analysis of its fine structure. In particular, it allows quantitative measurements of the wavelengths and line relative intensities.

Artist rendition of the planned Space Experiment Research and Processing Laboratory

NASA Technical Reports Server (NTRS)

2000-01-01

The preliminary design for the Space Experiment Research and Processing Laboratory (SERPL) at Kennedy Space Center is shown in this artist's rendition. The SERPL is a planned 100,000-square- foot laboratory that will provide expanded and upgraded facilities for hosting International Space Station experiment processing. In addition, it will provide better support for other biological and life sciences payload processing at KSC. It will serve as a magnet facility for a planned 400-acre Space Station Commerce Park.

Research and the planned Space Experiment Research and Processing Laboratory

NASA Technical Reports Server (NTRS)

2000-01-01

Researchers perform tests at Kennedy Space Center. New facilities for such research will be provided at the Space Experiment Research Procession Laboratory (SERPL). The SERPL is a planned 100,000-square-foot laboratory that will provide expanded and upgraded facilities for hosting International Space Station experiment processing. In addition, it will provide better support for other biological and life sciences payload processing at KSC. It will serve as a magnet facility for a planned 400-acre Space Station Commerce Park.

M[superscript 2+]•EDTA Binding Affinities: A Modern Experiment in Thermodynamics for the Physical Chemistry Laboratory

ERIC Educational Resources Information Center

O'Brien, Leah C.; Root, Hannah B.; Wei, Chin-Chuan; Jensen, Drake; Shabestary, Nahid; De Meo, Cristina; Eder, Douglas J.

2015-01-01

Isothermal titration calorimetry was used to experimentally determine thermodynamic values for the ethylenediaminetetraacetic acid (EDTA)(aq) + M[superscript 2+](aq) reactions (M[superscript 2+] = Ca[superscript 2+] and Mg[superscript 2+]). Students showed that for reactions in a N-(2-hydroxyethyl)piperazine-N"-ethanesulfonic acid (HEPES)…

Recycling Metals from Spent Screen-Printed Electrodes While Learning the Fundamentals of Electrochemical Sensing

ERIC Educational Resources Information Center

González-Sánchez, María-Isabel; Gómez-Monedero, Beatriz; Agrisuelas, Jerónimo; Valero, Edelmira

2018-01-01

A laboratory experiment in which students recycle silver and platinum selectively from spent screen-printed platinum electrodes is described. The recovered silver in solution is used to show its spontaneous redox reaction with a copper sheet. The recovered platinum is electrodeposited onto a screen-printed carbon electrode to develop a sensor for…

A Laboratory Experiment on Coupled Non-Identical Pendulums

ERIC Educational Resources Information Center

Li, Ang; Zeng, Jingyi; Yang, Hujiang; Xiao, Jinghua

2011-01-01

In this paper, coupled pendulums with different lengths are studied. Through steel magnets, each pendulum is coupled with others, and a stepping motor is used to drive the whole system. To record the data automatically, we designed a data acquisition system with a CCD camera connected to a computer. The coupled system shows in-phase, locked-phase…

Introduction to the Plant World, Science (Experimental): 5311.11.

ERIC Educational Resources Information Center

Payne, Leonard O.

This unit of instruction was designed as a laboratory-oriented course for very low achievers to show how plants are involved in every aspect of their lives. Detailed practical experience in handling and investigating plants, and the use of films, models, and field trips are combined with basic minimal research to guide the student to a better…

Microgravity

NASA Image and Video Library

1992-02-10

The image shows a test cell of Crystal Growth experiment inside the Vapor Crystal Growth System (VCGS) furnace aboard the STS-42, International Microgravity Laboratory-1 (IML-1), mission. The goal of IML-1, a pressurized marned Spacelab module, was to explore in depth the complex effects of weightlessness of living organisms and materials processing. More than 200 scientists from 16 countires participated in the investigations.

A Physics Show Performed by Students for Kids: "From Mechanics to Elementary Particle Physics"

ERIC Educational Resources Information Center

Dreiner, Herbi K.

2008-01-01

Physics students spend the early part of their training attending physics and mathematics lectures, solving problem sets, and experimenting in laboratory courses. The program is typically intensive and fairly rigid. They have little opportunity to follow their own curiosity or apply their knowledge. There have been many attempts to address this…

A Fieldmill for Measuring Atmospheric Electricity

ERIC Educational Resources Information Center

Thompson, Frank

2018-01-01

It is a well known fact that the Earth carries a net negative charge that produces a downward electrostatic field. The present experiment shows how this field can be measured with a Field Mill which has been constructed from components readily available in the Laboratory. In fine weather conditions a value of 120 (±10) V m[superscript -1] was…

Precision investigations of nuclei and nucleons with the (e, e'. gamma. ) reaction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Papanicolas, C.N.; Ammons, E.A.; Cardman, L.S.

1988-11-20

Recent theoretical and experimental investigations of the (e, e'..gamma..) reaction show that it provides a probe of unparalleled precision and selectivity. Experiments aimed towards the isolation of multipole form factors in mixed transitions, the study of continuum excitations in nuclei, and the measurement of the response of the proton are underway at several laboratories.

A fieldmill for measuring atmospheric electricity

NASA Astrophysics Data System (ADS)

Thompson, Frank

2018-03-01

It is a well known fact that the Earth carries a net negative charge that produces a downward electrostatic field. The present experiment shows how this field can be measured with a Field Mill which has been constructed from components readily available in the Laboratory. In fine weather conditions a value of 120 (±10) V m-1 was obtained which agrees with data in the literature. However, when a thunder storm was approaching preliminary measurements showed that the field varied between +400 V m-1 and -1000 V m-1 thus indicating complex charge states of the approaching clouds. Suggestions are made for improving the sensitivity of the apparatus so that experiments can be carried out for other weather conditions.

Analyzing Inquiry Questions of High-School Students in a Gas Chromatography Open-Ended Laboratory Experiment

ERIC Educational Resources Information Center

Blonder, Ron; Mamlock-Naaman, Rachel; Hofstein, Avi

2008-01-01

This paper describes the implementation of an open-ended inquiry experiment for high-school students, based on gas chromatography (GC). The research focuses on identifying the level of questions that students ask during the GC open inquiry laboratory, and it examines whether implementing the advanced inquiry laboratory opens up new directions for…

Implementation of Gas Chromatography and Microscale Distillation into the General Chemistry Laboratory Curriculum as Vehicles for Examining Intermolecular Forces

ERIC Educational Resources Information Center

Csizmar, Clifford M.; Force, Dee Ann; Warner, Don L.

2011-01-01

As part of an NSF-funded Course Curriculum and Laboratory Improvement (CCLI) project that seeks, in part, to increase student exposure to scientific instrumentation, a gas chromatography experiment has been integrated into the second-semester general chemistry laboratory curriculum. The experiment uses affordable, commercially available equipment…

A Multistep Organocatalysis Experiment for the Undergraduate Organic Laboratory: An Enantioselective Aldol Reaction Catalyzed by Methyl Prolinamide

ERIC Educational Resources Information Center

Wade, Edmir O.; Walsh, Kenneth E.

2011-01-01

In recent years, there has been an explosion of research concerning the area of organocatalysis. A multistep capstone laboratory project that combines traditional reactions frequently found in organic laboratory curriculums with this new field of research is described. In this experiment, the students synthesize a prolinamide-based organocatalyst…

A Graphical Simulation of Vapor-Liquid Equilibrium for Use as an Undergraduate Laboratory Experiment and to Demonstrate the Concept of Mathematical Modeling.

ERIC Educational Resources Information Center

Whitman, David L.; Terry, Ronald E.

1985-01-01

Demonstrating petroleum engineering concepts in undergraduate laboratories often requires expensive and time-consuming experiments. To eliminate these problems, a graphical simulation technique was developed for junior-level laboratories which illustrate vapor-liquid equilibrium and the use of mathematical modeling. A description of this…

Agreed Discoveries: Students' Negotiations in a Virtual Laboratory Experiment

ERIC Educational Resources Information Center

Karlsson, Goran; Ivarsson, Jonas; Lindstrom, Berner

2013-01-01

This paper presents an analysis of the scientific reasoning of a dyad of secondary school students about the phenomenon of dissolution of gases in water as they work on this in a simulated laboratory experiment. A web-based virtual laboratory was developed to provide learners with the opportunity to examine the influence of physical factors on gas…

A Moveable Feast--A Progressive Approach to the Unit Operations Laboratory

ERIC Educational Resources Information Center

Conner, Wm. Curtis, Jr.; Hammond, Karl D.; Laurence, Robert L.

2011-01-01

The authors describe an alternative format for the senior laboratory in which students are allowed--indeed, expected--to communicate with previous groups and build on their results. The effect is a unit operations laboratory in which students are empowered to propose the experiments they wish to do and in which the cumulative experience of the…

Team-Based Learning, Faculty Research, and Grant Writing Bring Significant Learning Experiences to an Undergraduate Biochemistry Laboratory Course

ERIC Educational Resources Information Center

Evans, Hedeel Guy; Heyl, Deborah L.; Liggit, Peggy

2016-01-01

This biochemistry laboratory course was designed to provide significant learning experiences to expose students to different ways of succeeding as scientists in academia and foster development and improvement of their potential and competency as the next generation of investigators. To meet these goals, the laboratory course employs three…

Determining the Quantum Efficiency for Activation of an Organometallic Photoinitiator for Cationic Polymerization: An Experiment for the Physical or Inorganic Chemistry Laboratory

ERIC Educational Resources Information Center

Hayes, David M.; Mahar, Maura; Schnabel, R. Chris; Shah, Paras; Lees, Alistair J.; Jakubek, Vladimir

2007-01-01

We present a new laboratory experiment on the photochemistry of organometallic [eta][superscript 5],[eta][superscript 6]-mixed-sandwich compounds, which is suitable for both the physical chemistry and inorganic chemistry laboratory. Specifically, students use 1,10-phenanthroline to trap the intermediate formed when…

Using Laboratory Experiments and Circuit Simulation IT Tools in an Undergraduate Course in Analog Electronics

ERIC Educational Resources Information Center

Baltzis, Konstantinos B.; Koukias, Konstantinos D.

2009-01-01

Laboratory-based courses play a significant role in engineering education. Given the role of electronics in engineering and technology, laboratory experiments and circuit simulation IT tools are used in their teaching in several academic institutions. This paper discusses the characteristics and benefits of both methods. The content and structure…

Numerical simulations of impacts involving porous bodies. II. Comparison with laboratory experiments

NASA Astrophysics Data System (ADS)

Jutzi, Martin; Michel, Patrick; Hiraoka, Kensuke; Nakamura, Akiko M.; Benz, Willy

2009-06-01

In this paper, we compare the outcome of high-velocity impact experiments on porous targets, composed of pumice, with the results of simulations by a 3D SPH hydrocode in which a porosity model has been implemented. The different populations of small bodies of our Solar System are believed to be composed, at least partially, of objects with a high degree of porosity. To describe the fragmentation of such porous objects, a different model is needed than that used for non-porous bodies. In the case of porous bodies, the impact process is not only driven by the presence of cracks which propagate when a stress threshold is reached, it is also influenced by the crushing of pores and compaction. Such processes can greatly affect the whole body's response to an impact. Therefore, another physical model is necessary to improve our understanding of the collisional process involving porous bodies. Such a model has been developed recently and introduced successfully in a 3D SPH hydrocode [Jutzi, M., Benz, W., Michel, P., 2008. Icarus 198, 242-255]. Basic tests have been performed which already showed that it is implemented in a consistent way and that theoretical solutions are well reproduced. However, its full validation requires that it is also capable of reproducing the results of real laboratory impact experiments. Here we present simulations of laboratory experiments on pumice targets for which several of the main material properties have been measured. We show that using the measured material properties and keeping the remaining free parameters fixed, our numerical model is able to reproduce the outcome of these experiments carried out under different impact conditions. This first complete validation of our model, which will be tested for other porous materials in the future, allows us to start addressing problems at larger scale related to small bodies of our Solar System, such as collisions in the Kuiper Belt or the formation of a family by the disruption of a porous parent body in the main asteroid belt.

Detecting Pore Fluid Pressure Changes by Using the Vp/Vs Ratio

NASA Astrophysics Data System (ADS)

Vanorio, T.; Mavko, G.

2006-12-01

A central problem in studies aimed at predicting the dynamic behavior of faults is monitoring and quantifying fluid changes in areas prone to overpressure. Experimental and modeling studies show the Vp/Vs ratio to be a good determinant of the saturation state of a rock formation as well as of its inner pore pressure condition. Dectecting pore pressure changes depends, among other causes, on the reliability of laboratory data to calibrate the in-situ measured velocities. Ideally, laboratory experiments performed under controlled conditions would identify the fundamental mechanisms responsible for changes in the measured acoustic properties. However, technical limitations in the laboratory together with the assumptions driving the experimental and modeling approaches rise spouriuos mechanisms which hinder our present understanding of the actual role of high pore pressure on the elastic and poroelastic parameters. Critical issues unclude: a) the frequencies used in the laboratory are responsible for high-frequency fluid effects which induce velocity dispersion. As a result, both the effective stress parameter and velocities (and their pressure-dependence) estimated from high- frequency ultrasonic data are different from those applicable to crustal low frequency wave propagation; b) laboratory measurements made at dry, drained conditions are assumed to mimic those in gas pressured rocks. However, in dry, drained conditions, no pore pressure is exerted in the pore space, and the pore gas is infinitely compressible; c) when using room-dry, drained measurements as the baseline to model pressured rock formations, the unloading path (i.e. decreasing confining pressure) is supposed to mimic the inflationary path due to pore pressure increase. Doing so, it is assumed that the amount of crack opening due to pore pressure is equal to that of crack closure caused by the overburden stress and thus, the effective stress coefficient is implicitely assumed equal to 1. To minimize the assumptions and limitations described above, we designed a laboratory experiment which used gas as pore fluid medium. Experimental results show that in gas-pressured saturated rocks the Vp/Vs ratio, while remaining lower than values reported for liquid saturation conditions, increases with decreasing differential pressure, similarly to the trend observed in liquid saturated rocks.

Chloroplast incorporation and long-term photosynthetic performance through the life cycle in laboratory cultures of Elysia timida (Sacoglossa, Heterobranchia)

PubMed Central

2014-01-01

Introduction The Mediterranean sacoglossan Elysia timida is one of the few sea slug species with the ability to sequester chloroplasts from its food algae and to subsequently store them in a functional state in the digestive gland cells for more than a month, during which time the plastids retain high photosynthetic activity (= long-term retention). Adult E. timida have been described to feed on the unicellular alga Acetabularia acetabulum in their natural environment. The suitability of E. timida as a laboratory model culture system including its food source was studied. Results In contrast to the literature reporting that juvenile E. timida feed on Cladophora dalmatica first, and later on switch to the adult diet A. acetabulum, the juveniles in this study fed directly on A. acetabulum (young, non-calcified stalks); they did not feed on the various Cladophora spp. (collected from the sea or laboratory culture) offered. This could possibly hint to cryptic speciation with no clear morphological differences, but incipient ecological differentiation. Transmission electron microscopy of chloroplasts from A. acetabulum after initial intake by juvenile E. timida showed different states of degradation — in conglomerations or singularly — and fragments of phagosome membranes, but differed from kleptoplast images of C. dalmatica in juvenile E. timida from the literature. Based on the finding that the whole life cycle of E. timida can be completed with A. acetabulum as the sole food source, a laboratory culture system was established. An experiment with PAM-fluorometry showed that cultured E. timida are also able to store chloroplasts in long-term retention from Acetabularia peniculus, which stems from the Indo-Pacific and is not abundant in the natural environment of E. timida. Variations between three experiment groups indicated potential influences of temperature on photosynthetic capacities. Conclusions E. timida is a viable laboratory model system to study photosynthesis in incorporated chloroplasts (kleptoplasts). Capacities of chloroplast incorporation in E. timida were investigated in a closed laboratory culture system with two different chloroplast donors and over extended time periods about threefold longer than previously reported. PMID:24428892

A novel capacitance sensor for fireside corrosion measurement.

PubMed

Ban, Heng; Li, Zuoping

2009-11-01

Fireside corrosion in coal-fired power plants is a leading mechanism for boiler tube failures. Online monitoring of fireside corrosion can provide timely data to plant operators for mitigation implementation. This paper presents a novel sensor concept for measuring metal loss based on electrical capacitance. Laboratory-scale experiments demonstrated the feasibility of design, fabrication, and operation of the sensor. The fabrication of the prototype sensor involved sputtering deposition of a thin metal coating with varying thickness on a ceramic substrate. Corrosion metal loss resulted in a proportional decrease in electrical capacitance of the sensor. Laboratory experiments using a muffle furnace with an oxidation environment demonstrated that low carbon steel coatings on ceramic substrate survived cyclic temperatures over 500 degrees C. Measured corrosion rates of sputtered coating in air had an Arrhenius exponential dependence on temperature, with metal thickness loss ranging from 2.0 nm/h at 200 degrees C to 2.0 microm/h at 400 degrees C. Uncertainty analysis indicated that the overall measurement uncertainty was within 4%. The experimental system showed high signal-to-noise ratio, and the sensor could measure submicrometer metal thickness changes. The laboratory experiments demonstrated that the sensor concept and measurement system are capable of short term, online monitoring of metal loss, indicating the potential for the sensor to be used for fireside corrosion monitoring and other metal loss measurement.

Numerical modelling of gravel unconstrained flow experiments with the DAN3D and RASH3D codes

NASA Astrophysics Data System (ADS)

Sauthier, Claire; Pirulli, Marina; Pisani, Gabriele; Scavia, Claudio; Labiouse, Vincent

2015-12-01

Landslide continuum dynamic models have improved considerably in the last years, but a consensus on the best method of calibrating the input resistance parameter values for predictive analyses has not yet emerged. In the present paper, numerical simulations of a series of laboratory experiments performed at the Laboratory for Rock Mechanics of the EPF Lausanne were undertaken with the RASH3D and DAN3D numerical codes. They aimed at analysing the possibility to use calibrated ranges of parameters (1) in a code different from that they were obtained from and (2) to simulate potential-events made of a material with the same characteristics as back-analysed past-events, but involving a different volume and propagation path. For this purpose, one of the four benchmark laboratory tests was used as past-event to calibrate the dynamic basal friction angle assuming a Coulomb-type behaviour of the sliding mass, and this back-analysed value was then used to simulate the three other experiments, assumed as potential-events. The computational findings show good correspondence with experimental results in terms of characteristics of the final deposits (i.e., runout, length and width). Furthermore, the obtained best fit values of the dynamic basal friction angle for the two codes turn out to be close to each other and within the range of values measured with pseudo-dynamic tilting tests.

A novel capacitance sensor for fireside corrosion measurement

NASA Astrophysics Data System (ADS)

Ban, Heng; Li, Zuoping

2009-11-01

Fireside corrosion in coal-fired power plants is a leading mechanism for boiler tube failures. Online monitoring of fireside corrosion can provide timely data to plant operators for mitigation implementation. This paper presents a novel sensor concept for measuring metal loss based on electrical capacitance. Laboratory-scale experiments demonstrated the feasibility of design, fabrication, and operation of the sensor. The fabrication of the prototype sensor involved sputtering deposition of a thin metal coating with varying thickness on a ceramic substrate. Corrosion metal loss resulted in a proportional decrease in electrical capacitance of the sensor. Laboratory experiments using a muffle furnace with an oxidation environment demonstrated that low carbon steel coatings on ceramic substrate survived cyclic temperatures over 500 °C. Measured corrosion rates of sputtered coating in air had an Arrhenius exponential dependence on temperature, with metal thickness loss ranging from 2.0 nm/h at 200 °C to 2.0 μm/h at 400 °C. Uncertainty analysis indicated that the overall measurement uncertainty was within 4%. The experimental system showed high signal-to-noise ratio, and the sensor could measure submicrometer metal thickness changes. The laboratory experiments demonstrated that the sensor concept and measurement system are capable of short term, online monitoring of metal loss, indicating the potential for the sensor to be used for fireside corrosion monitoring and other metal loss measurement.

Glycosidation of Methanol with Ribose: An Interdisciplinary Undergraduate Laboratory Experiment

ERIC Educational Resources Information Center

Simon, Erin; Cook, Katie; Pritchard, Meredith R.; Stripe, Wayne; Bruch, Martha; Bendinskas, Kestutis

2010-01-01

This exercise provides students hands-on experience with the topics of glycosidation, hemiacetal and acetal formation, proton nuclear magnetic resonance ([superscript 1]H NMR) spectroscopy, and kinetic and thermodynamic product formation. In this laboratory experiment, the methyl acetal of ribose is synthesized, and the kinetic and thermodynamic…

Experimenting with Inexpensive Plastic Springs

ERIC Educational Resources Information Center

Perez, Leander; Marques, Adriana; Sánchez, Iván

2014-01-01

Acommon undergraduate laboratory experience is the determination of the elastic constant of a spring, whether studying the elongation under a static load or studying the damped harmonic motion of the spring with a suspended mass. An alternative approach to this laboratory experience has been suggested by Menezes et al., aimed at studying the…

Remote Teaching Experiments on Magnetic Domains in Thin Films

ERIC Educational Resources Information Center

Dobrogowski, W.; Maziewski, A.; Zablotskii, V.

2007-01-01

We describe our experience in building a remote laboratory for teaching magnetic domains. Fulfilling the proposed on-line experiments, students can observe and study magnetization processes that are often difficult to explain with written material. It is proposed that networks of remotely accessible laboratories could be integrated in the Global…

High-Performance Liquid Chromatography in the Undergraduate Chemical Engineering Laboratory

ERIC Educational Resources Information Center

Frey, Douglas D.; Guo, Hui; Karnik, Nikhila

2013-01-01

This article describes the assembly of a simple, low-cost, high-performance liquid chromatography (HPLC) system and its use in the undergraduate chemical engineering laboratory course to perform simple experiments. By interpreting the results from these experiments students are able to gain significant experience in the general method of…

Enhancing the Student Experience of Laboratory Practicals through Digital Video Guides

ERIC Educational Resources Information Center

Croker, Karen; Andersson, Holger; Lush, David; Prince, Rob; Gomez, Stephen

2010-01-01

Laboratory-based learning allows students to experience bioscience principles first hand. In our experience, practical content and equipment may have changed over time, but teaching methods largely remain the same, typically involving; whole class introduction with a demonstration, students emulating the demonstration in small groups, gathering…

Utilizing Problem-Based Learning in Qualitative Analysis Lab Experiments

ERIC Educational Resources Information Center

Hicks, Randall W.; Bevsek, Holly M.

2012-01-01

A series of qualitative analysis (QA) laboratory experiments utilizing a problem-based learning (PBL) module has been designed and implemented. The module guided students through the experiments under the guise of cleaning up a potentially contaminated water site as employees of an environmental chemistry laboratory. The main goal was the…

In Situ Techniques for Monitoring Electrochromism: An Advanced Laboratory Experiment

ERIC Educational Resources Information Center

Saricayir, Hakan; Uce, Musa; Koca, Atif

2010-01-01

This experiment employs current technology to enhance and extend existing lab content. The basic principles of spectroscopic and electroanalytical techniques and their use in determining material properties are covered in some detail in many undergraduate chemistry programs. However, there are limited examples of laboratory experiments with in…

Teaching pediatric laboratory medicine to pathology residents.

PubMed

Pysher, Theodore J; Bach, Philip R; Geaghan, Sharon M; Hamilton, Marilyn S; Laposata, Michael; Lockitch, Gillian; Brugnara, Carlo; Coffin, Cheryl M; Pasquali, Marzia; Rinaldo, Piero; Roberts, William L; Rutledge, Joe C; Ashwood, Edward R; Blaylock, Robert C; Campos, Joseph M; Goldsmith, Barbara; Jones, Patricia M; Lim, Megan; Meikle, A Wayne; Perkins, Sherrie L; Perry, Deborah A; Petti, Cathy A; Rogers, Beverly B; Steele, Paul E; Weiss, Ronald L; Woods, Gail

2006-07-01

Laboratory data are essential to the medical care of fetuses, infants, children, and adolescents. However, the performance and interpretation of laboratory tests on specimens from these patients, which may constitute a significant component of the workload in general hospitals and integrated health care systems as well as specialized perinatal or pediatric centers, present unique challenges to the clinical pathologist and the laboratory. Therefore, pathology residents should receive training in pediatric laboratory medicine. Children's Health Improvement through Laboratory Diagnostics, a group of pathologists and laboratory scientists with interest and expertise in pediatric laboratory medicine, convened a task force to develop a list of curriculum topics, key resources, and training experiences in pediatric laboratory medicine for trainees in anatomic and clinical pathology or straight clinical pathology residency programs and in pediatric pathology fellowship programs. Based on the experiences of 11 training programs, we have compiled a comprehensive list of pediatric topics in the areas of clinical chemistry, endocrinology, hematology, urinalysis, coagulation medicine, transfusion medicine, immunology, microbiology and virology, biochemical genetics, cytogenetics and molecular diagnostics, point of care testing, and laboratory management. This report also includes recommendations for training experiences and a list of key texts and other resources in pediatric laboratory medicine. Clinical pathologists should be trained to meet the laboratory medicine needs of pediatric patients and to assist the clinicians caring for these patients with the selection and interpretation of laboratory studies. This review helps program directors tailor their curricula to more effectively provide this training.

Geophysical Properties of Hard Rock for Investigation of Stress Fields in Deep Mines

NASA Astrophysics Data System (ADS)

Tibbo, M.; Young, R. P.; Schmitt, D. R.; Milkereit, B.

2014-12-01

A complication in geophysical monitoring of deep mines is the high-stress dependency of the physical properties of hard rocks. In-mine observations show anisotropic variability of the in situ P- and S-wave velocities and resistivity of the hard rocks that are likely related to stress field changes. As part of a comprehensive study in a deep, highly stressed mine located in Sudbury, Ontario, Canada, data from in situ monitoring of the seismicity, conductivity, stress, and stress dependent physical properties has been obtain. In-laboratory experiments are also being performed on borehole cores from the Sudbury mines. These experiments will measure the Norite borehole core's properties including elastic modulus, bulk modulus, P- and S-wave velocities, and density. Hydraulic fracturing has been successfully implemented in industries such as oil and gas and enhanced geothermal systems, and is currently being investigated as a potential method for preconditioning in mining. However, further research is required to quantify how hydraulic fractures propagate through hard, unfractured rock as well as naturally fractured rock typically found in mines. These in laboratory experiments will contribute to a hydraulic fracturing project evaluating the feasibility and effectiveness of hydraulic fracturing as a method of de-stressing hard rock mines. A tri-axial deformation cell equipped with 18 Acoustic Emission (AE) sensors will be used to bring the borehole cores to a tri-axial state of stress. The cores will then be injected with fluid until the the hydraulic fracture has propagated to the edge of the core, while AE waveforms will be digitized continuously at 10 MHz and 12-bit resolution for the duration of each experiment. These laboratory hydraulic fracture experiments will contribute to understanding how parameters including stress ratio, fluid injection rate, and viscosity, affect the fracturing process.

Creating a Driven, Collapsed Radiative Shock in the Laboratory

NASA Astrophysics Data System (ADS)

Reighard, Amy

2006-10-01

We report details of the first experimental campaign to create a driven, planar, radiatively collapsed in laboratory experiment. Radiation hydrodynamics experiments are challenging to realize in a laboratory setting, requiring high temperatures in a system of sufficient extent. The Omega laser at ˜10^15 W/cm^2 drives a thin slab of low-Z material at >100 km/s gas via laser ablation pressure. This slab initially shocks, then continues driving a shock through a cylindrical volume of Xe gas at 6 mg/cc. Simulations predict a collapsed layer in which the density reaches ˜45 times initial density. Side-on x-ray backlighting was the principal diagnostic. We have successfully imaged shocks with average velocities between 95-205 km/sec, with measured thicknesses of 45-150 μm in experiments lasting up to 20 ns and spanning up 2.5 mm in extent. Comparison of the shock position as a function of time from these experiments to 1D radiation hydrodynamic simulation results show some discrepancy, which will be explored. Optical depth before and behind the shock is important for meaningful comparison to these astrophysical systems. This shock is optically thin to emitted radiation in the unshocked region and optically thick to radiation in the shocked, dense region. We compare this system to collapsed shocks in astrophysical systems with similar optical depth profiles. An experiment using a Thomson scattering diagnostic across the shock front is also discussed. This research was sponsored by the National Nuclear Security Administration under the Stewardship Science Academic Alliances program through DOE Research Grants DE-FG52-03NA00064, DE-FG53-2005-NA26014, and other grants and contracts.

Zvezda Launch Coverage

NASA Technical Reports Server (NTRS)

2000-01-01

Footage shows the Proton Rocket (containing the Zvezda module) ready for launch at the Baikonur Cosmodrome in Kazakhstan, Russia. The interior and exterior of Zvezda are seen during construction. Computerized simulations show the solar arrays deploying on Zvezda in space, the maneuvers of the module as it approaches and connects with the International Space Station (ISS), the installation of the Z1 truss on the ISS and its solar arrays deploying, and the installations of the Destiny Laboratory, Remote Manipulator System, and Kibo Experiment Module. Live footage then shows the successful launch of the Proton Rocket.

The Absorption Spectrum of Iodine Vapour

ERIC Educational Resources Information Center

Tetlow, K. S.

1972-01-01

A laboratory experiment is described which presents some molecular parameters of iodine molecule by studying iodine spectrum. Points out this experiment can be conducted by sixth form students in high school laboratories. (PS)

A Simple Optical Waveguide Experiment.

ERIC Educational Resources Information Center

Phelps, J.; Sambles, J. R.

1989-01-01

Describes a thin film rectangular dielectric waveguide and its laboratory use. Discusses the theory of uniaxial thin film waveguides with mathematical expressions and the laboratory procedures for a classroom experiment with diagrams. (Author/YP)

High Performance Liquid Chromatography Experiments to Undergraduate Laboratories

ERIC Educational Resources Information Center

Kissinger, Peter T.; And Others

1977-01-01

Reviews the principles of liquid chromatography with electrochemical detection (LCEC), an analytical technique that incorporates the advantages of both liquids chromatography and electrochemistry. Also suggests laboratory experiments using this technique. (MLH)

A single sample study of dissociation between expressed and experienced pleasure by gender in mild depression.

PubMed

Brown, S L

Thirty male and thirty female adult subjects were divided equally into three groups on the basis of the Zung Self-Rating Depression Scale; mildly depressed (50-63), normal (40-49), and "low normal" (20-39). Observer ratings of positive affect were made during a one and one-half hour laboratory experiment, and self-ratings of pleasurable experience were collected at the end of the experiment. Results showed no significant differences between groups for self-report of experienced pleasure. However, a significant difference between groups was found for observer ratings of positive affect, with the mildly depressed and "low normal" subjects showing a shorter duration and a lower degree of positive affect than the normals. These results partially replicate and extended previous work. Implications for theory, research, and psychotherapy are discussed.

A Virtual Rock Physics Laboratory Through Visualized and Interactive Experiments

NASA Astrophysics Data System (ADS)

Vanorio, T.; Di Bonito, C.; Clark, A. C.

2014-12-01

As new scientific challenges demand more comprehensive and multidisciplinary investigations, laboratory experiments are not expected to become simpler and/or faster. Experimental investigation is an indispensable element of scientific inquiry and must play a central role in the way current and future generations of scientist make decisions. To turn the complexity of laboratory work (and that of rocks!) into dexterity, engagement, and expanded learning opportunities, we are building an interactive, virtual laboratory reproducing in form and function the Stanford Rock Physics Laboratory, at Stanford University. The objective is to combine lectures on laboratory techniques and an online repository of visualized experiments consisting of interactive, 3-D renderings of equipment used to measure properties central to the study of rock physics (e.g., how to saturate rocks, how to measure porosity, permeability, and elastic wave velocity). We use a game creation system together with 3-D computer graphics, and a narrative voice to guide the user through the different phases of the experimental protocol. The main advantage gained in employing computer graphics over video footage is that students can virtually open the instrument, single out its components, and assemble it. Most importantly, it helps describe the processes occurring within the rock. These latter cannot be tracked while simply recording the physical experiment, but computer animation can efficiently illustrate what happens inside rock samples (e.g., describing acoustic waves, and/or fluid flow through a porous rock under pressure within an opaque core-holder - Figure 1). The repository of visualized experiments will complement lectures on laboratory techniques and constitute an on-line course offered through the EdX platform at Stanford. This will provide a virtual laboratory for anyone, anywhere to facilitate teaching/learning of introductory laboratory classes in Geophysics and expand the number of courses that can be offered for curricula in Earth Sciences. The primary goal is to open up a research laboratory such as the one available at Stanford to promising students worldwide who are currently left out of such educational resources.

Juvenile female rats, but not male rats, show renewal, reinstatement, and spontaneous recovery following extinction of conditioned fear.

PubMed

Park, Chun Hui J; Ganella, Despina E; Kim, Jee Hyun

2017-12-01

Anxiety disorders emerge early, and girls are significantly more likely to develop anxiety compared to boys. However, sex differences in fear during development are poorly understood. Therefore, we investigated juvenile male and female rats in the relapse behaviors following extinction of conditioned fear. In all experiments, 18-d-old rats first received three white-noise-footshock pairings on day 1. On day 2, extinction involved 60 white-noise alone trials. In experiment 1, we examined renewal by testing the rats in either the same or different context as extinction on day 3. Male rats did not show renewal, however, female rats showed renewal. Experiment 2 investigated reinstatement by giving rats either a mild reminder footshock or context exposure on day 3. When tested the next day, male rats did not show reinstatement, whereas female rats showed reinstatement. Experiment 3 investigated spontaneous recovery by testing the rats either 1 or 5 d following extinction. Male rats did not show any spontaneous recovery whereas female rats did. Taken together, fear regulation appear to be different in males versus females from early in development, which may explain why girls are more prone to suffer from anxiety disorders compared to boys. © 2017 Park et al.; Published by Cold Spring Harbor Laboratory Press.

Laser Speckle Photography: Some Simple Experiments for the Undergraduate Laboratory.

ERIC Educational Resources Information Center

Bates, B.; And Others

1986-01-01

Describes simple speckle photography experiments which are easy to set up and require only low cost standard laboratory equipment. Included are procedures for taking single, double, and multiple exposures. (JN)

The 5th Annual NASA Spacecraft Control Laboratory Experiment (SCOLE) Workshop, part 2

NASA Technical Reports Server (NTRS)

Taylor, Lawrence W., Jr. (Compiler)

1990-01-01

A collection of papers from the workshop are presented. The topics addressed include: the modeling, systems identification, and control synthesis for the Spacecraft Control Laboratory Experiment (SCOLE) configuration.

Geophysical Fluid Dynamics Laboratory Open Days at the Woods Hole Oceanographic Institution

NASA Astrophysics Data System (ADS)

Hyatt, Jason; Cenedese, Claudia; Jensen, Anders

2015-11-01

This event was hosted for one week for two consecutive years in 2013 and 2014. It targeted postdocs, graduate students, K-12 students and local community participation. The Geophysical Fluid Dynamics Laboratory at the Woods Hole Oceanographic Institution hosted 10 hands-on demonstrations and displays, with something for all ages, to share the excitement of fluid mechanics and oceanography. The demonstrations/experiments spanned as many fluid mechanics problems as possible in all fields of oceanography and gave insight into using fluids laboratory experiments as a research tool. The chosen experiments were `simple' yet exciting for a 6 year old child, a high school student, a graduate student, and a postdoctoral fellow from different disciplines within oceanography. The laboratory is a perfect environment in which to create excitement and stimulate curiosity. Even what we consider `simple' experiments can fascinate and generate interesting questions from both a 6 year old child and a physics professor. How does an avalanche happen? How does a bath tub vortex form? What happens to waves when they break? How does a hurricane move? Hands-on activities in the fluid dynamics laboratory helped students of all ages in answering these and other intriguing questions. The laboratory experiments/demonstrations were accompanied by `live' videos to assist in the interpretation of the demonstrations. Posters illustrated the oceanographic/scientific applicability and the location on Earth where the dynamics in the experiments occur. Support was given by the WHOI Doherty Chair in Education.

Teaching Optics Topics in College Physics Laboratory*

NASA Astrophysics Data System (ADS)

Kezerashvili, Roman Y.

2006-12-01

We propose a list of designed experiments that could be presented at the laboratory class in the second semester of College and University Physics courses to study properties of light. The study of light can be organized into three domains: geometric optics, wave optics and quantum optics. These domains are not strictly disjoint. In the sets of experiments for the first domain students study the laws of reflection and refraction of light by measuring the dependence of the angles of reflection and refraction on the angle of incident, spherical mirrors and lenses, geometric optics of human eye. In the sets of experiments for the second domain students study the wave properties of light: dispersion, interference, diffraction and polarization. Experiments designed to verify the Malus's law and measure the Brewster's angle, determine the wavelength of laser light and study the interference on a transmission and reflection diffraction grating, diffraction on the different size slits and wires. The purposes of experiments for the third domain are to study the spectral lines of different gases, determine the Rydberg's constant from the spectrum of hydrogen atom, and verify the laws of the photoelectric effect and Einstein's quantum idea. The objectives of all experiments are to show the real action of physics laws, help students better understand and visualize the subject of the lecture. *Supported by US Department of Education grant P120A060052

ESR Experiments on a Single Donor Electron in Isotopically Enriched Silicon

NASA Astrophysics Data System (ADS)

Tracy, Lisa; Luhman, Dwight; Carr, Stephen; Borchardt, John; Bishop, Nathaniel; Ten Eyck, Gregory; Pluym, Tammy; Wendt, Joel; Witzel, Wayne; Blume-Kohout, Robin; Nielsen, Erik; Lilly, Michael; Carroll, Malcolm

In this talk we will discuss electron spin resonance experiments in single donor silicon qubit devices fabricated at Sandia National Labs. A self-aligned device structure consisting of a polysilicon gate SET located adjacent to the donor is used for donor electron spin readout. Using a cryogenic HEMT amplifier next to the silicon device, we demonstrate spin readout at 100 kHz bandwidth and Rabi oscillations with 0.96 visibility. Electron spin resonance measurements on these devices show a linewidth of 30 kHz and coherence times T2* = 10 us and T2 = 0.3 ms. We also discuss estimates of the fidelity of our donor electron spin qubit measurements using gate set tomography. This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. DOE Office of Basic Energy Sciences user facility. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000. ESR Experiments on a Single Donor Electron in Isotopically Enriched Silicon.

Concurrent performance in a three-alternative choice situation: response allocation in a Rock/Paper/Scissors game.

PubMed

Kangas, Brian D; Berry, Meredith S; Cassidy, Rachel N; Dallery, Jesse; Vaidya, Manish; Hackenberg, Timothy D

2009-10-01

Adult human subjects engaged in a simulated Rock/Paper/Scissors game against a computer opponent. The computer opponent's responses were determined by programmed probabilities that differed across 10 blocks of 100 trials each. Response allocation in Experiment 1 was well described by a modified version of the generalized matching equation, with undermatching observed in all subjects. To assess the effects of instructions on response allocation, accurate probability-related information on how the computer was programmed to respond was provided to subjects in Experiment 2. Five of 6 subjects played the counter response of the computer's dominant programmed response near-exclusively (e.g., subjects played paper almost exclusively if the probability of rock was high), resulting in minor overmatching, and higher reinforcement rates relative to Experiment 1. On the whole, the study shows that the generalized matching law provides a good description of complex human choice in a gaming context, and illustrates a promising set of laboratory methods and analytic techniques that capture important features of human choice outside the laboratory.

Short communication: Analytical method and amount of preservative added to milk samples may alter milk urea nitrogen measurements.

PubMed

Weeks, Holley L; Hristov, Alexander N

2017-02-01

Milk urea N (MUN) is used by dairy nutritionists and producers to monitor dietary protein intake and is indicative of N utilization in lactating dairy cows. Two experiments were conducted to explore discrepancies in MUN results provided by 3 milk processing laboratories using different methods. An additional experiment was conducted to evaluate the effect of 2-bromo-2-nitropropane-1, 3-diol (bronopol) on MUN analysis. In experiment 1, 10 replicates of bulk tank milk samples, collected from the Pennsylvania State University's Dairy Center over 5 consecutive days, were sent to 3 milk processing laboratories in Pennsylvania. Average MUN differed between laboratory A (14.9 ± 0.40 mg/dL; analyzed on MilkoScan 4000; Foss, Hillerød, Denmark), laboratory B (6.5 ± 0.17 mg/dL; MilkoScan FT + 6000), and laboratory C (7.4 ± 0.36 mg/dL; MilkoScan 6000). In experiment 2, milk samples were spiked with urea at 0 (7.3 to 15.0 mg/dL, depending on the laboratory analyzing the samples), 17.2, 34.2, and 51.5 mg/dL of milk. Two 35-mL samples from each urea level were sent to the 3 laboratories used in experiment 1. Average analyzed MUN was greater than predicted (calculated for each laboratory based on the control; 0 mg of added urea): for laboratory A (23.2 vs. 21.0 mg/dL), laboratory B (18.0 vs. 13.3 mg/dL), and laboratory C (20.6 vs. 15.2 mg/dL). In experiment 3, replicated milk samples were preserved with 0 to 1.35 mg of bronopol/mL of milk and submitted to one milk processing laboratory that analyzed MUN using 2 different methods. Milk samples with increasing amounts of bronopol ranged in MUN concentration from 7.7 to 11.9 mg/dL and from 9.0 to 9.3 mg/dL when analyzed on MilkoScan 4000 or CL 10 (EuroChem, Moscow, Russia), respectively. In conclusion, measured MUN concentrations varied due to analytical procedure used by milk processing laboratories and were affected by the amount of bronopol used to preserve milk sample, when milk was analyzed using a mid-infrared analyzer. Thus, it is important to maintain consistency in milk sample preservation and analysis to ensure precision of MUN results. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Reconfiguring practice: the interdependence of experimental procedure and computing infrastructure in distributed earthquake engineering.

PubMed

De La Flor, Grace; Ojaghi, Mobin; Martínez, Ignacio Lamata; Jirotka, Marina; Williams, Martin S; Blakeborough, Anthony

2010-09-13

When transitioning local laboratory practices into distributed environments, the interdependent relationship between experimental procedure and the technologies used to execute experiments becomes highly visible and a focal point for system requirements. We present an analysis of ways in which this reciprocal relationship is reconfiguring laboratory practices in earthquake engineering as a new computing infrastructure is embedded within three laboratories in order to facilitate the execution of shared experiments across geographically distributed sites. The system has been developed as part of the UK Network for Earthquake Engineering Simulation e-Research project, which links together three earthquake engineering laboratories at the universities of Bristol, Cambridge and Oxford. We consider the ways in which researchers have successfully adapted their local laboratory practices through the modification of experimental procedure so that they may meet the challenges of coordinating distributed earthquake experiments.

Molecular beam scattering from C-13 enriched Kapton and correlation with the EOIM-3 carousel experiment

NASA Technical Reports Server (NTRS)

Minton, Timothy K.; Moore, Teresa A.

1995-01-01

Mass spectra of products emerging from identical samples of a C-13-enriched polyimide polymer (chemically equivalent to Kapton) under atomic oxygen bombardment in space and in the laboratory were collected. Reaction products unambiguously detected in space were CO-13, NO, (12)CO2, and (13)CO2. These reaction products and two others, H2O and CO-12, were detected in the laboratory, along with inelastically scattered atomic and molecular oxygen. Qualitative agreement was seen in the mass spectra taken in space and in the laboratory; the agreement may be improved by reducing the fraction of O2 in the laboratory molecular beam. Both laboratory and space data indicated that CO and CO2 products come preferentially from reaction with the imide component of the polymer chain, raising the possibility that the either component may degrade in part by the 'evaporation' of higher molecular weight fragments. Laboratory time-of-flight distributions showed: (1) incomplete energy accommodation of impinging O and O2 species that do not react with the surface; and (2) both hyperthermal and thermal CO and CO2 products, suggesting two distinct reaction mechanisms with the surface.

Definition of experiments and instruments for a communication/navigation research laboratory. Volume 3: Laboratory descriptions

NASA Technical Reports Server (NTRS)

1972-01-01

The following study objectives are covered: (1) identification of major laboratory equipment; (2) systems and operations analysis in support of the laboratory design; and (3) conceptual design of the comm/nav research laboratory.

SCORPI and SCORPI-T: Neurophysiological experiments on animals in space

NASA Astrophysics Data System (ADS)

Serafini, L.; Ramacciotti, T.; Vigano, W.; Donati, A.; Porciani, M.; Zolesi, V.; Schulze-Varnholt, D.; Manieri, P.; El-Din Sallam, A.; Schmah, M.; Horn, E. R.

2005-08-01

The study of physiological adaptation to long-term space flights with special consideration of the internal clock systems of scorpions is the goal of the SCORPI and SCORPI-T experiments. SCORPI was selected for flight on the International Space Station (ISS) and will be mounted in the European facility BIOLAB, the ESA laboratory designed to support biological experiments on micro-organisms, cells, tissue, cultures, small plants and small invertebrates. SCORPI-T experiment, performed on the Russian FOTON-M2 satellite in May-June 2005, represents an important precursor for the success of the experiment SCORPI on BIOLAB. This paper outlines the main features of the hardware designed and developed in order to allow the analysis of critical aspects of experiment execution and the verification of experiment objectives. The capabilities of the hardware developed for SCORPI and SCORPI-T show its potential use for any future similar type of experiments in space.

Transient plasma estimation: a noise cancelling/identification approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Candy, J.V.; Casper, T.; Kane, R.

1985-03-01

The application of a noise cancelling technique to extract energy storage information from sensors occurring during fusion reactor experiments on the Tandem Mirror Experiment-Upgrade (TMX-U) at the Lawrence Livermore National Laboratory (LLNL) is examined. We show how this technique can be used to decrease the uncertainty in the corresponding sensor measurements used for diagnostics in both real-time and post-experimental environments. We analyze the performance of algorithm on the sensor data and discuss the various tradeoffs. The algorithm suggested is designed using SIG, an interactive signal processing package developed at LLNL.

Erosion waves: Transverse instabilities and fingering

NASA Astrophysics Data System (ADS)

Malloggi, F.; Lanuza, J.; Andreotti, B.; Clément, E.

2006-09-01

Two laboratory scale experiments of dry and underwater avalanches of non-cohesive granular materials are investigated. We trigger solitary waves and study the conditions under which the front is transversally stable. We show the existence of a linear instability followed by a coarsening dynamics and finally the onset of a fingering pattern. Due to the different operating conditions, both experiments strongly differ by the spatial and time scales involved. Nevertheless, the quantitative agreement between the stability diagram, the wavelengths selected and the avalanche morphology suggest a common scenario for an erosion/deposition process.

uSOP: A Microprocessor-Based Service-Oriented Platform for Control and Monitoring

NASA Astrophysics Data System (ADS)

Aloisio, Alberto; Ameli, Fabrizio; Anastasio, Antonio; Branchini, Paolo; Di Capua, Francesco; Giordano, Raffaele; Izzo, Vincenzo; Tortone, Gennaro

2017-06-01

uSOP is a general purpose single-board computer designed for deep embedded applications in control and monitoring of detectors, sensors, and complex laboratory equipment. In this paper, we present and discuss the main aspects of the hardware and software designs and the expandable peripheral architecture built around serial busses. We show the tests done with state-of-the-art ΔΣ 24-b ADC acquisition modules, in order to assess the achievable noise floor in a typical application. Eventually, we report on the deployment of uSOP in the monitoring system framework of the Belle2 experiment, presently under construction at the KEK Laboratory (Tsukuba, Japan).

Impact of Multimedia and Network Services on an Introductory Level Course

NASA Technical Reports Server (NTRS)

Russ, John C.

1996-01-01

We will demonstrate and describe the impact of our use of multimedia and network connectivity on a sophomore-level introductory course in materials science. This class services all engineering students, resulting in large (more than 150) class sections with no hands-on laboratory. In 1990 we began to develop computer graphics that might substitute for some laboratory or real-world experiences, and demonstrate relationships hard to show with static textbook images or chalkboard drawings. We created a comprehensive series of modules that cover the entire course content. Called VIMS (Visualizations in Materials Science), these are available in the form of a CD-ROM and also via the internet.

Experimental operation of a sodium heat pipe

NASA Astrophysics Data System (ADS)

Holtz, R. E.; McLennan, G. A.; Koehl, E. R.

1985-05-01

This report documents the operation of a 28 in. long sodium heat pipe in the Heat Pipe Test Facility (HPTF) installed at Argonne National Laboratory. Experimental data were collected to simulate conditions prototypic of both a fluidized bed coal combustor application and a space environment application. Both sets of experiment data show good agreement with the heat pipe analytical model. The heat transfer performance of the heat pipe proved reliable over a substantial period of operation and over much thermal cycling. Additional testing of longer heat pipes under controlled laboratory conditions will be necessary to determine performance limitations and to complete the design code validation.

Efficacy and security of ivermectin given orally to rats naturally infected with Syphacia spp., Giardia spp. and Hymenolepis nana.

PubMed

Foletto, V R S; Vanz, F; Gazarini, L; Stern, C A J; Tonussi, C R

2015-07-01

The results of this study show that the oral administration of ivermectin (48 mg/L) repeatedly for 72 h used in accordance with the present protocol is a safe and highly effective treatment for Giardia spp. and Hymenolepis nana in laboratory rat colonies. The drug can be easily and safely administered using drinking water. This simple regimen should control pinworm infection (Syphacia muris), a problem that can be endemic in laboratory colonies. Experiments using healthy animals are likely to generate more consistent results, thereby requiring a reduced number of animals per group. © The Author(s) 2014.

Soundscapes and Larval Settlement: Larval Bivalve Responses to Habitat-Associated Underwater Sounds.

PubMed

Eggleston, David B; Lillis, Ashlee; Bohnenstiehl, DelWayne R

2016-01-01

We quantified the effects of habitat-associated sounds on the settlement response of two species of bivalves with contrasting habitat preferences: (1) Crassostrea virginicia (oyster), which prefers to settle on other oysters, and (2) Mercenaria mercenaria (clam), which settles on unstructured habitats. Oyster larval settlement in the laboratory was significantly higher when exposed to oyster reef sound compared with either off-reef or no-sound treatments. Clam larval settlement did not vary according to sound treatments. Similar to laboratory results, field experiments showed that oyster larval settlement in "larval housings" suspended above oyster reefs was significantly higher compared with off-reef sites.

Closing the loop on improvement: Packaging experience in the Software Engineering Laboratory

NASA Technical Reports Server (NTRS)

Waligora, Sharon R.; Landis, Linda C.; Doland, Jerry T.

1994-01-01

As part of its award-winning software process improvement program, the Software Engineering Laboratory (SEL) has developed an effective method for packaging organizational best practices based on real project experience into useful handbooks and training courses. This paper shares the SEL's experience over the past 12 years creating and updating software process handbooks and training courses. It provides cost models and guidelines for successful experience packaging derived from SEL experience.