Systemic calicivirus epidemic in captive exotic felids.

PubMed

Harrison, Tara M; Sikarskie, James; Kruger, John; Wise, Annabel; Mullaney, Thomas P; Kiupel, Matti; Maes, Roger K

2007-06-01

A 5-day-old, mother-raised, Amur tiger cub (Panthera tigris altaica) presented with tongue ulcerations. Identical lesions appeared and progressed to sloughing of the tongue in the three littermates of this cub the following day. The lesions progressed in all cubs to include sloughing of the carpal, tarsal, metacarpal, and metatarsal foot pad epithelium. Oral ulcerations were also noted in adult African lions (Panthera leo) and Amur tigers (Panthera tigris altaica), but not in two adult snow leopards (Panthera uncia) housed in the same building. All adult cats had been previously vaccinated for common feline diseases including feline calicivirus (FCV). Detection of FCV RNA in oral secretions by a real-time reverse transcription polymerase chain reaction assay (RRT-PCR) confirmed FCV infection in the tiger cubs and one lion. A male lion and a male tiger cub died during the disease outbreak. RRT-PCR confirmed FCV in multiple tissues in both of these animals. A stray cat live-trapped outside the feline building during the epidemic was found to be positive for FCV by virus isolation and was thought to be the source of infection.

Thermal Inactivation of Feline Calicivirus in Pet Food Processing.

PubMed

Haines, J; Patel, M; Knight, A I; Corley, D; Gibson, G; Schaaf, J; Moulin, J; Zuber, S

2015-12-01

Extrusion is the most common manufacturing process used to produce heat-treated dry dog and cat food (pet food) for domestic use and international trade. Due to reoccurring outbreaks of notifiable terrestrial animal diseases and their impact on international trade, experiments were undertaken to demonstrate the effectiveness of heat-treated extruded pet food on virus inactivation. The impact of extrusion processing in a pet food matrix on virus inactivation has not been previously reported and very few inactivation studies have examined the thermal inactivation of viruses in complex food matrices. The feline calicivirus vaccine strain FCV F-9 was used as a surrogate model RNA virus pathogen. Small-scale heat inactivation experiments using animal-derived pet food raw materials showed that a > 4 log10 reduction (log10 R) in infectivity occurred at 70 °C prior to reaching the minimum extrusion manufacturing operating temperature of 100 °C. As anticipated, small-scale pressure studies at extrusion pressure (1.6 MPa) showed no apparent effect on FCV F-9 inactivation. Additionally, FCV F-9 was shown not to survive the acidic conditions used to produce pet food palatants of animal origin that are typically used as a coating after the extrusion process.

Nitrile/Buna N Material Failure Assessment for an O-Ring used on the Gaseous Hydrogen Flow Control Valve (FCV) of the Space Shuttle Main Engine

NASA Technical Reports Server (NTRS)

Wingard, Doug

2006-01-01

After the rollout of Space Shuttle Discovery in April 2005 in preparation for return-to-flight, there was a failure of the Orbiter (OV-103) helium signature leak test in the gaseous hydrogen (GH2) system. Leakage was attributed to the Flow Control Valve (FCV) in Main Engine 3. The FCV determined to be the source of the leak for OV-103 is designated as LV-58. The nitrile/Buna N rubber O-ring seal was removed from LV-58, and failure analysis indicated radial cracks providing leak paths in one quadrant. Cracks were eventually found in 6 of 9 FCV O-rings among the three Shuttle Orbiters, though none were as severe as those for LV-58, OV-103. Testing by EM10 at MSFC on all 9 FCV O- rings included: laser dimensional, Shore A hardness and properties from a dynamic mechanical analyzer (DMA) and an Instron tensile machine. The following test data was obtained on the cracked quadrant of the LV-58, OV-103 O-ring: (1) the estimated compression set was only 9.5%, compared to none for the rest of the O-ring; (2) Shore A hardness for the O.D. was higher by almost 4 durometer points than for the rest of the O-ring; and (3) DMA data showed that the storage/elastic modulus E was almost 25% lower than for the rest of the O-ring. Of the 8 FCV O-rings tested on an Instron, 4 yielded tensile strengths that were below the MIL spec requirement of 1350 psi-a likely influence of rubber cracking. Comparisons were made between values of modulus determined by DNA (elastic) and Instron (Young s). Each nitrile/Buna N O-ring used in the FCV conforms to the MIL-P-25732C specification. A number of such O-rings taken from shelf storage at MSFC and Kennedy Space Center (KSC) were used to generate a reference curve of DMA glass transition temperature (Tg) vs. shelf storage time ranging from 8 to 26 years. A similar reference curve of TGA onset temperature (of rubber weight loss) vs. shelf storage time was also generated. The DMA and TGA data for the used FCV O-rings were compared to the reference curves. Correlations were also made between the DMA modulus (at 22 C) and Shore A hardness for all 9 of the FCV O-rings used among the three Shuttle Orbiters. The radial cracking in the FCV O-rings was determined to be due to ozone attack, as nitrile/Buna N rubber is susceptible to such attack. Nitrile/Buna N material under MIL-P25732C should be used in a hydraulic fluid environment to help protect it from cracking. However, the FCV O-rings were used in an air only environment. The FCV design has as much as a 9-mil gap that allows the O.D. of the O-ring to be directly exposed to ozone, pressurized air and some elevated temperatures, accelerating the weathering process that leads to O-ring cracking. Space Shuttle flights will likely not continue past 2010. Therefore, Shuttle management decided to continue using the nitrile/Buna N material for the FCVs, but have each O-ring replaced after 3 years to minimize any chances for crack initiation.

A novel and easy FxCycle™ violet based flow cytometric method for simultaneous assessment of DNA ploidy and six-color immunophenotyping.

PubMed

Tembhare, Prashant; Badrinath, Yajamanam; Ghogale, Sitaram; Patkar, Nikhil; Dhole, Nilesh; Dalavi, Pooja; Kunder, Nikesh; Kumar, Ashok; Gujral, Sumeet; Subramanian, P G

2016-03-01

Abnormal DNA ploidy is a valuable prognostic factor in many neoplasms, especially in hematological neoplasms like B-cell acute lymphoblastic leukemia (B-ALL) and multiple myeloma (MM). Current methods of flow-cytometric (FC) DNA-ploidy evaluation are either technically difficult or limited to three- to four-color immunophenotyping and hence, challenging to evaluate DNA-ploidy in minute tumor population with background rich of its normal counterpart cells and other hematopoietic cells. We standardized a novel sensitive and easy method of simultaneous evaluation of six- to seven-color immunophenotyping and DNA-ploidy using a dye-FxCycle Violet (FCV). Linearity, resolution, and coefficient of variation (CV) for FCV were studied using chicken erythrocyte nuclei. Ploidy results of FCV were compared with Propidium iodide (PI) in 20 samples and intra-assay variation for FCV was studied. Using this six-color immunophenotyping & FCV-protocol DNA-ploidy was determined in bone-marrow samples from 124 B-ALL & 50 MM patients. Dilution experiment was also conducted to determine the sensitivity in detection of aneuploidy in minute tumor population. FCV revealed high linearity and resolution in 450/50 channel. On comparison with PI, CV of Go/G1-peak with FCV (mean-CV 4.1%) was slightly higher than PI (mean-CV 2.9%) but had complete agreement in ploidy results. Dilution experiment showed that aneuploidy could be accurately detected up to the limit of 0.01% tumor cells. Intra-assay variation was very low with CV of 0.005%. In B-ALL, hypodiploidy was noted in 4%, hyperdiploidy in 24%, near-hyperdiploidy in 13% and remaining 59% were diploid. In MM, hypodiploidy was in 2%, hyperdiploidy in 58%, near-hyperdiploidy in 8% and remaining 30% were diploid. FCV-based DNA-ploidy method is a sensitive and easy method for simultaneous evaluation of six-color immunophenotyping and DNA analysis. It is useful in DNA-ploidy evaluation of minute tumor population in cases like minimal residual disease and MM precursor conditions. © 2015 International Society for Advancement of Cytometry.

Relevance of feline calicivirus, feline immunodeficiency virus, feline leukemia virus, feline herpesvirus and Bartonella henselae in cats with chronic gingivostomatitis.

PubMed

Belgard, Sylvia; Truyen, Uwe; Thibault, Jean-Christophe; Sauter-Louis, Carola; Hartmann, Katrin

2010-01-01

Despite its common occurrence, the aetiology of chronic gingivostomatitis in cats remains uncertain. Aetiology is likely multifactorial, and several infectious agents may be associated with chronic gingivostomatitis. The purpose of this study was to investigate the prevalence of feline calicivirus (FCV), feline immunodeficiency virus (FIV), feline leukemia virus (FeLV), feline herpesvirus (FHV), and Bartonella henselae (B. henselae) in cats with chronic gingivostomatitis and in an age-matched control group. In addition, other factors, e. g., environmental conditions were investigated. In 52 cats with chronic gingivostomatitis and 50 healthy age-matched control cats, the presence of FCV ribonucleic acid (RNA), and FHV deoxyribonucleic acid (DNA) (polymerase chain reaction [PCR] from oropharyngeal swabs), and B. henselae DNA (PCR from oropharyngeal swabs and blood), as well as FeLV antigen (serum), and antibodies against FCV, B. henselae, and FIV (serum) were examined. FCV RNA was significantly more common in cats with chronic gingivostomatitis (53.8%, p < 0.001) than in controls (14.0%); a significant difference was also found in the prevalence of antibodies to FCV between the cats with chronic gingivostomatitis (78.8%, p = 0.023) and controls (58.0%). Of the other infectious agents investigated, there was no significant difference in the prevalence between the cats with chronic gingivostomatitis and the controls. The results of this study allow the conclusion that FCV, but no other infectious agents, is commonly associated with chronic gingivostomatitis in cats.

Food choice considerations among American Indians living in rural Oklahoma: The THRIVE study.

PubMed

Wetherill, Marianna S; Williams, Mary B; Hartwell, Micah L; Salvatore, Alicia L; Jacob, Tvli; Cannady, Tamela K; Standridge, Joy; Fox, Jill; Spiegel, Jennifer; Anderson, Natia; Jernigan, Valarie Blue Bird

2018-05-17

In rural American Indian (AI) communities, access to affordable, healthy foods is often limited. Understanding AI food choice considerations when selecting foods, such as sensory appeal, cost, or health, is an important yet understudied topic for eliminating persistent AI health disparities. In partnership with the Chickasaw Nation and Choctaw Nation of Oklahoma, we administered a modified version of the Food Choice Values (FCV) Questionnaire to a cross-sectional sample of 83 AI patrons shopping at tribally-owned convenience stores ≥3 times per week. The FCV Questionnaire uses 25 items to assess eight FCV subscales related to buying and eating food, including sensory appeal; safety; accessibility; convenience; health/weight control; organic; tradition; and comfort. We compared mean scores for each FCV subscale by demographic groups using t-tests and ANOVA. We used confirmatory factor analysis (CFA) to examine how well the data from this population fit FCV subscale constructs. We then used cluster analysis, MANOVA, and discriminant analysis to characterize distinct segments of the population based on patterns of FCV endorsement. Appeal, safety, and access FCVs were most strongly endorsed across the sample. Prioritization of FCVs varied by age, gender, income, and education. Our cluster analysis identified four groups, or segments, each with distinct patterns of FCV endorsement: limited endorsement of any FCVs (23.3%); safety and sensory appeal (32.9%); health/weight control (17.8%); and broad endorsement of FCVs (26.0%). These groups varied by age and employment status. Findings from this analysis informed the design and implementation of a healthy retail intervention comprised of new healthful foods and beverages, product placement and marketing strategies within four tribally-owned and operated convenience stores. Public health interventions aimed at reducing nutrition-related disparities in rural AI populations may benefit from assessing food choice considerations. Copyright © 2018 Elsevier Ltd. All rights reserved.

Virucidal efficacy of disinfectant actives against feline calicivirus, a surrogate for norovirus, in a short contact time.

PubMed

Whitehead, Kelly; McCue, Karen A

2010-02-01

Among other measures, handwashing and targeted disinfection are important in preventing and controlling norovirus outbreaks. Presently, there are a limited number of disinfectants effective against norovirus. There is a need to develop alternatives to bleach that are effective against norovirus, and, in particular, fast-acting disinfectants are desired. The aim of this study was to determine the disinfectant actives and formulation factors necessary to achieve efficacy against norovirus in a short contact time. Feline calicivirus (FCV) was used as a surrogate for norovirus. In a carrier test method, common disinfectant actives including alcohol, acid, quaternary compound, and phenol both alone and as formulated disinfectants were contacted with dried FCV virus for 1 minute. The virus treatment was neutralized and assayed in Crandell-Reese kidney cells for cytopathic effect. Log(10) virus inactivation was calculated comparing treatment results to virus control titer. Bleach and acid-based disinfectants inactivate FCV in 1 minute. Inactivation of FCV by alcohol and quaternary actives depends on how these actives are formulated as disinfectants. Actives and extreme pH are determined predictive of efficacy. Ethanol and quaternary compounds formulated at appropriate concentration and alkaline pH inactivates FCV in 1-minute contact. Acid cleaners, ethanol, and quaternary compounds formulated at appropriate concentration and pH can be fast-acting antimicrobial choices and alternatives to bleach for the consumer and health care providers to use to inactivate FCV, a surrogate for norovirus, and protect against this important pathogen. Copyright 2010 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Adaptive Fault Detection on Liquid Propulsion Systems with Virtual Sensors: Algorithms and Architectures

NASA Technical Reports Server (NTRS)

Matthews, Bryan L.; Srivastava, Ashok N.

2010-01-01

Prior to the launch of STS-119 NASA had completed a study of an issue in the flow control valve (FCV) in the Main Propulsion System of the Space Shuttle using an adaptive learning method known as Virtual Sensors. Virtual Sensors are a class of algorithms that estimate the value of a time series given other potentially nonlinearly correlated sensor readings. In the case presented here, the Virtual Sensors algorithm is based on an ensemble learning approach and takes sensor readings and control signals as input to estimate the pressure in a subsystem of the Main Propulsion System. Our results indicate that this method can detect faults in the FCV at the time when they occur. We use the standard deviation of the predictions of the ensemble as a measure of uncertainty in the estimate. This uncertainty estimate was crucial to understanding the nature and magnitude of transient characteristics during startup of the engine. This paper overviews the Virtual Sensors algorithm and discusses results on a comprehensive set of Shuttle missions and also discusses the architecture necessary for deploying such algorithms in a real-time, closed-loop system or a human-in-the-loop monitoring system. These results were presented at a Flight Readiness Review of the Space Shuttle in early 2009.

Molecular and clinical study on prevalence of feline herpesvirus type 1 and calicivirus in correlation with feline leukemia and immunodeficiency viruses.

PubMed

Najafi, Hamideh; Madadgar, Omid; Jamshidi, Shahram; Ghalyanchi Langeroudi, Arash; Darzi Lemraski, Mahdieh

2014-01-01

Upper respiratory tract diseases (URTD) are common clinical problem in cats worldwide. Feline calicivirus (FCV) and feline herpesvirus type 1 (FHV-1) are the main primary pathogens. Feline immunodeficiency virus (FIV) and Feline leukemia virus (FeLV) are also among the most common infectious diseases of cats which suppress the immunity. Oropharyngeal and conjunctival swabs and blood samples were taken from 16 cats with clinical signs of URTD and 26 clinically healthy cats. PCR and RT-PCR were used to detect FHV/FIV or FCV/FeLV infections, respectively. Feline calicivirus was detected in all cats with URTD and 87.00% and 93.00% of them were positive for FIV and FeLV, respectively. Feline herpesvirus rate of infection was 43.00% in sick cats. In clinically normal cats, prevalence rates of FCV and FHV were about 50.00%, but FIV and FeLV rates (42.00% and 65.00% respectively) were higher compared to other studies. Stomatitis was observed in 50.00% of cats with URTD. The main causative agent of corneal ulcers is FHV-1, but in 50.00% of cats with corneal ulcers, FCV was detected alone. It seems new variants of Caliciviruses are the main causative agents to attack uncommon tissues like cornea, although retroviral infections may be in the background of these various signs. The high retroviral prevalence may be due to existence of large population of stray cats. This is the first molecular study of FeLV and FCV in Iran and seems that FCV and FHV prevalence rates in FIV or FeLV infected cats is more than other non-infected ones.

Molecular and clinical study on prevalence of feline herpesvirus type 1 and calicivirus in correlation with feline leukemia and immunodeficiency viruses

PubMed Central

Najafi, Hamideh; Madadgar, Omid; Jamshidi, Shahram; Ghalyanchi Langeroudi, Arash; Darzi Lemraski, Mahdieh

2014-01-01

Upper respiratory tract diseases (URTD) are common clinical problem in cats worldwide. Feline calicivirus (FCV) and feline herpesvirus type 1 (FHV-1) are the main primary pathogens. Feline immunodeficiency virus (FIV) and Feline leukemia virus (FeLV) are also among the most common infectious diseases of cats which suppress the immunity. Oropharyngeal and conjunctival swabs and blood samples were taken from 16 cats with clinical signs of URTD and 26 clinically healthy cats. PCR and RT-PCR were used to detect FHV/FIV or FCV/FeLV infections, respectively. Feline calicivirus was detected in all cats with URTD and 87.00% and 93.00% of them were positive for FIV and FeLV, respectively. Feline herpesvirus rate of infection was 43.00% in sick cats. In clinically normal cats, prevalence rates of FCV and FHV were about 50.00%, but FIV and FeLV rates (42.00% and 65.00% respectively) were higher compared to other studies. Stomatitis was observed in 50.00% of cats with URTD. The main causative agent of corneal ulcers is FHV-1, but in 50.00% of cats with corneal ulcers, FCV was detected alone. It seems new variants of Caliciviruses are the main causative agents to attack uncommon tissues like cornea, although retroviral infections may be in the background of these various signs. The high retroviral prevalence may be due to existence of large population of stray cats. This is the first molecular study of FeLV and FCV in Iran and seems that FCV and FHV prevalence rates in FIV or FeLV infected cats is more than other non-infected ones. PMID:25610576

Space Shuttle Program (SSP) Orbiter Main Propulsion System (MPS) Gaseous Hydrogen (GH2) Flow Control Valve (FCV) Poppet Eddy Current (EC) Inspection Probability of Detection (POD) Study. Volume 1

NASA Technical Reports Server (NTRS)

Piascik, Robert S.; Prosser, William H.

2011-01-01

The Director of the NASA Engineering and Safety Center (NESC), requested an independent assessment of the anomalous gaseous hydrogen (GH2) flow incident on the Space Shuttle Program (SSP) Orbiter Vehicle (OV)-105 during the Space Transportation System (STS)-126 mission. The main propulsion system (MPS) engine #2 GH2 flow control valve (FCV) LV-57 transition from low towards high flow position without being commanded. Post-flight examination revealed that the FCV LV-57 poppet had experienced a fatigue failure that liberated a section of the poppet flange. The NESC assessment provided a peer review of the computational fluid dynamics (CFD), stress analysis, and impact testing. A probability of detection (POD) study was requested by the SSP Orbiter Project for the eddy current (EC) nondestructive evaluation (NDE) techniques that were developed to inspect the flight FCV poppets. This report contains the findings and recommendations from the NESC assessment.

Space Shuttle Program (SSP) Orbiter Main Propulsion System (MPS) Gaseous Hydrogen (GH2) Flow Control Valve (FCV) Poppet Eddy Current (EC) Inspection Probability of Detection (POD) Study. Volume 2; Appendices

NASA Technical Reports Server (NTRS)

Piascik, Robert S.; Prosser, William H.

2011-01-01

The Director of the NASA Engineering and Safety Center (NESC), requested an independent assessment of the anomalous gaseous hydrogen (GH2) flow incident on the Space Shuttle Program (SSP) Orbiter Vehicle (OV)-105 during the Space Transportation System (STS)-126 mission. The main propulsion system (MPS) engine #2 GH2 flow control valve (FCV) LV-57 transition from low towards high flow position without being commanded. Post-flight examination revealed that the FCV LV-57 poppet had experienced a fatigue failure that liberated a section of the poppet flange. The NESC assessment provided a peer review of the computational fluid dynamics (CFD), stress analysis, and impact testing. A probability of detection (POD) study was requested by the SSP Orbiter Project for the eddy current (EC) nondestructive evaluation (NDE) techniques that were developed to inspect the flight FCV poppets. This report contains the Appendices to the main report.

Tenacity of human norovirus and the surrogates feline calicivirus and murine norovirus during long-term storage on common nonporous food contact surfaces.

PubMed

Mormann, Sascha; Heißenberg, Cathrin; Pfannebecker, Jens; Becker, Barbara

2015-01-01

The transfer of human norovirus (hNV) to food via contaminated surfaces is highly probable during food production, processing, and preparation. In this study, the tenacity of hNV and its cultivable surrogates feline calicivirus (FCV) and murine norovirus (MNV) on two common nonporous surface materials at two storage temperatures was directly compared. Virus titer reduction on artificially inoculated stainless steel and plastic carriers was monitored for 70 days at room temperature and at 7°C. Viruses were recovered at various time points by elution. Genomes from intact capsids (hNV, FCV, and MNV) were quantified with real-time reverse transcription (RT) PCR, and infectivity (FCV and MNV) was assessed with plaque assay. RNase treatment before RNA extraction was used to eliminate exposed RNA and to assess capsid integrity. No significant differences in titer reduction were found between materials (stainless steel or plastic) with the plaque assay or the real-time quantitative RT-PCR. At room temperature, infectious FCV and MNV were detected for 7 days. Titers of intact hNV, FCV, and MNV capsids dropped gradually and were still detectable after 70 days with a loss of 3 to 4 log units. At 7°C, the viruses were considerably more stable than they were at room temperature. Although only MNV infectivity was unchanged after 70 days, the numbers of intact capsids (hNV, FCV, and MNV) were stable with less than a 1-log reduction. The results indicate that hNV persists on food contact surfaces and seems to remain infective for weeks. MNV appears to be more stable than FCV at 7°C, and thus is the most suitable surrogate for hNV under dry conditions. Although a perfect quantitative correlation between intact capsids and infective particles was not obtained, real-time quantitative RT-PCR provided qualitative data about hNV inactivation characteristics. The results of this comparative study might support future efforts in assessment of foodborne virus risk and food safety.

Onset of immunity in kittens after vaccination with a non-adjuvanted vaccine against feline panleucopenia, feline calicivirus and feline herpesvirus.

PubMed

Jas, D; Aeberlé, C; Lacombe, V; Guiot, A L; Poulet, H

2009-10-01

The induction of a quick onset of immunity against feline parvovirus (FPV), feline herpesvirus (FHV) and feline calicivirus (FCV) is critical both in young kittens after the decline of maternal antibodies and in cats at high risk of exposure. The onset of immunity for the core components was evaluated in 8-9 week old specific pathogen free kittens by challenge 1 week after vaccination with a combined modified live (FPV, FHV) and inactivated (FCV) vaccine. The protection obtained 1 week after vaccination was compared to that obtained when the challenge was performed 3-4 weeks after vaccination. The protocol consisted of a single injection for vaccination against FPV and two injections 4 weeks apart for FHV and FCV. At 1 week after vaccination, the kittens showed no FPV-induced clinical signs or leukopenia following challenge, and after FCV and FHV challenges the clinical score was significantly lower in vaccinated animals than in controls. Interestingly, the relative efficacy of the vaccination was comparable whether the animals were challenged 1 week or 3-4 weeks after vaccination, indicating that the onset of protection occurred within 7 days of vaccination. Following the 1-week challenge, excretion of FPV, FHV and FCV was significantly reduced in vaccinated cats compared to control kittens, confirming the onset of immunity within 7 days of vaccination.

New Proof-of-Concept in Viral Inactivation: Virucidal Efficacy of 405 nm Light Against Feline Calicivirus as a Model for Norovirus Decontamination.

PubMed

Tomb, Rachael M; Maclean, Michelle; Coia, John E; Graham, Elizabeth; McDonald, Michael; Atreya, Chintamani D; MacGregor, Scott J; Anderson, John G

2017-06-01

The requirement for novel decontamination technologies for use in hospitals is ever present. One such system uses 405 nm visible light to inactivate microorganisms via ROS-generated oxidative damage. Although effective for bacterial and fungal inactivation, little is known about the virucidal effects of 405 nm light. Norovirus (NoV) gastroenteritis outbreaks often occur in the clinical setting, and this study was designed to investigate potential inactivation effects of 405 nm light on the NoV surrogate, feline calicivirus (FCV). FCV was exposed to 405 nm light whilst suspended in minimal and organically-rich media to establish the virucidal efficacy and the effect biologically-relevant material may play in viral susceptibility. Antiviral activity was successfully demonstrated with a 4 Log 10 (99.99%) reduction in infectivity when suspended in minimal media evident after a dose of 2.8 kJ cm -2 . FCV exposed in artificial faeces, artificial saliva, blood plasma and other organically rich media exhibited an equivalent level of inactivation using between 50-85% less dose of the light, indicating enhanced inactivation when the virus is present in organically-rich biologically-relevant media. Further research in this area could aid in the development of 405 nm light technology for effective NoV decontamination within the hospital environment.

Response of feral cats to vaccination at the time of neutering.

PubMed

Fischer, Sarah M; Quest, Cassie M; Dubovi, Edward J; Davis, Rolan D; Tucker, Sylvia J; Friary, John A; Crawford, P Cynda; Ricke, Teri A; Levy, Julie K

2007-01-01

To determine whether administration of inactivated virus or modified-live virus (MLV) vaccines to feral cats at the time of neutering induces protective serum antiviral antibody titers. Prospective study. 61 feral cats included in a trap-neuter-return program in Florida. Each cat received vaccines against feline panleukopenia virus (FPV), feline herpes virus (FHV), feline calicivirus (FCV), FeLV, and rabies virus (RV). Immediately on completion of surgery, vaccines that contained inactivated RV and FeLV antigens and either MLV or inactivated FPV, FHV, and FCV antigens were administered. Titers of antiviral antibodies (except those against FeLV) were assessed in serum samples obtained immediately prior to surgery and approximately 10 weeks later. Prior to vaccination, some of the cats had protective serum antibody titers against FPV (33%), FHV (21%), FCV (64%), and RV (3%). Following vaccination, the overall proportion of cats with protective serum antiviral antibody titers increased (FPV [90%], FHV [56%], FCV [93%], and RV [98%]). With the exception of the FHV vaccine, there were no differences in the proportions of cats protected with inactivated virus versus MLV vaccines. Results suggest that exposure to FPV, FHV, and FCV is common among feral cats and that a high proportion of cats are susceptible to RV infection. Feral cats appeared to have an excellent immune response following vaccination at the time of neutering. Incorporation of vaccination into trap-neuter-return programs is likely to protect the health of individual cats and possibly reduce the disease burden in the community.

Microbicidal effects of weakly acidified chlorous acid water against feline calicivirus and Clostridium difficile spores under protein-rich conditions

PubMed Central

Goda, Hisataka; Yamaoka, Hitoshi; Nakayama-Imaohji, Haruyuki; Kawata, Hiroyuki; Horiuchi, Isanori; Fujita, Yatsuka; Nagao, Tamiko; Tada, Ayano; Terada, Atsushi; Kuwahara, Tomomi

2017-01-01

Sanitation of environmental surfaces with chlorine based-disinfectants is a principal measure to control outbreaks of norovirus or Clostridium difficile. The microbicidal activity of chlorine-based disinfectants depends on the free available chlorine (FAC), but their oxidative potential is rapidly eliminated by organic matter. In this study, the microbicidal activities of weakly acidified chlorous acid water (WACAW) and sodium hypochlorite solution (NaClO) against feline calcivirus (FCV) and C. difficile spores were compared in protein-rich conditions. WACAW inactivated FCV and C. difficile spores better than NaClO under all experimental conditions used in this study. WACAW above 100 ppm FAC decreased FCV >4 log10 within 30 sec in the presence of 0.5% each of bovine serum albumin (BSA), polypeptone or meat extract. Even in the presence of 5% BSA, WACAW at 600 ppm FAC reduced FCV >4 log10 within 30 sec. Polypeptone inhibited the virucidal activity of WACAW against FCV more so than BSA or meat extract. WACAW at 200 ppm FAC decreased C. difficile spores >3 log10 within 1 min in the presence of 0.5% polypeptone. The microbicidal activity of NaClO was extensively diminished in the presence of organic matter. WACAW recovered its FAC to the initial level after partial neutralization by sodium thiosulfate, while no restoration of the FAC was observed in NaClO. These results indicate that WACAW is relatively stable under organic matter-rich conditions and therefore may be useful for treating environmental surfaces contaminated by human excretions. PMID:28472060

A comparison of the thermal inactivation kinetics of human norovirus surrogates and hepatitis A virus in buffered cell culture medium.

PubMed

Bozkurt, Hayriye; D'Souza, Doris H; Davidson, P Michael

2014-09-01

Human noroviruses and hepatitis A virus (HAV) are considered as epidemiologically significant causes of foodborne disease. Therefore, studies are needed to bridge existing data gaps and determine appropriate parameters for thermal inactivation of human noroviruses and HAV. The objectives of this research were to compare the thermal inactivation kinetics of human norovirus surrogates (murine norovirus (MNV-1), and feline calicivirus (FCV-F9)) and HAV in buffered medium (2-ml vials), compare first-order and Weibull models to describe the data, calculate Arrhenius activation energy for each model, and evaluate model efficiency using selected statistical criteria. The D-values calculated from the first-order model (50-72 °C) ranged from 0.21-19.75 min for FCV-F9, 0.25-36.28 min for MNV-1, and 0.88-56.22 min for HAV. Using the Weibull model, the tD = 1 (time to destroy 1 log) for FCV-F9, MNV-1 and HAV at the same temperatures ranged from 0.10-13.27, 0.09-26.78, and 1.03-39.91 min, respectively. The z-values for FCV-F9, MNV-1, and HAV were 9.66 °C, 9.16 °C, and 14.50 °C, respectively, using the Weibull model. For the first order model, z-values were 9.36 °C, 9.32 °C, and 12.49 °C for FCV-F9, MNV-1, and HAV, respectively. For the Weibull model, estimated activation energies for FCV-F9, MNV-1, and HAV were 225, 278, and 182 kJ/mol, respectively, while the calculated activation energies for the first order model were 195, 202, and 171 kJ/mol, respectively. Knowledge of the thermal inactivation kinetics of norovirus surrogates and HAV will allow the development of processes that produce safer food products and improve consumer safety. Copyright © 2014. Published by Elsevier Ltd.

Effects of sanitation, freezing and frozen storage on enteric viruses in berries and herbs.

PubMed

Butot, S; Putallaz, T; Sánchez, G

2008-08-15

Norovirus (NV) and hepatitis A virus (HAV) are foodborne enteric viruses associated with outbreaks of disease following consumption of fresh or frozen produce. Model experiments were performed to determine the effectiveness of certain commercial processes for the removal of enteric viruses that might be present in berries and herbs. The survival and persistence of HAV, NV, rotavirus (RV) and feline calicivirus (FCV), a surrogate for NV, in frozen produce over time were determined. Survival and inactivation of HAV, RV and FCV were assessed by viral culture and quantitative reverse transcription-PCR (RT-PCR), whereas NV persistence was determined by quantitative RT-PCR only. Freezing did not significantly reduce the viability of any of the viruses except the infectivity of FCV in strawberries. Frozen storage for 3 months had limited effects on HAV and RV survival in all tested food products, whereas in frozen raspberries and strawberries FCV infectivity showed the highest decay rate due to acid pH. To simulate postharvesting conditions, fresh berries and herbs were rinsed with tap, warm or chlorinated water or with a chlorine dioxide (ClO(2)) solution. Available chlorine at a concentration of 200 ppm and ClO(2) at 10 ppm reduced measurable enteric viruses in raspberry and parsley samples by less than 2 log(10) units.

Recovery Optimization and Survival of the Human Norovirus Surrogates Feline Calicivirus and Murine Norovirus on Carpet

PubMed Central

Buckley, David; Fraser, Angela; Huang, Guohui

2017-01-01

ABSTRACT Carpets have been implicated in prolonged and reoccurring outbreaks of human noroviruses (HuNoV), the leading cause of acute gastroenteritis worldwide. Viral recovery from environmental surfaces, such as carpet, remains undeveloped. Our aim was to determine survival of HuNoV surrogates on an understudied environmental surface, carpet. First, we measured the zeta potential and absorption capacity of wool and nylon carpet fibers, we then developed a minispin column elution (MSC) method, and lastly we characterized the survival of HuNoV surrogates, feline calicivirus (FCV) and murine norovirus (MNV), over 60 days under 30 and 70% relative humidity (RH) on two types of carpet and one glass surface. Carpet surface charge was negative between relevant pH values (i.e., pH 7 to 9). In addition, wool could absorb approximately two times more liquid than nylon. The percent recovery efficiency obtained by the MSC method ranged from 4.34 to 20.89% and from 30.71 to 54.14% for FCV and MNV on carpet fibers, respectively, after desiccation. Overall, elution buffer type did not significantly affect recovery. Infectious FCV or MNV survived between <1 and 15 or between 3 and 15 days, respectively. However, MNV survived longer under some conditions and at significantly (P < 0.05) higher titers compared to FCV. Albeit, surrogates followed similar survival trends, i.e., both survived longest on wool then nylon and glass, while 30% RH provided a more hospitable environment compared to 70% RH. Reverse transcription-quantitative PCR signals for both surrogates were detectable for the entire study, but FCV genomic copies experienced significantly higher reductions (<3.80 log10 copies) on all surfaces compared to MNV (<1.10 log10 copies). IMPORTANCE Human noroviruses (HuNoV) are the leading cause of acute gastroenteritis worldwide. Classical symptoms of illness include vomiting and diarrhea which could lead to severe dehydration and death. HuNoV are transmitted by the fecal-oral or vomitus-oral route via person-to-person contact, food, water, and/or environmental surfaces. Published laboratory-controlled studies have documented the environmental stability of HuNoV on hard surfaces, but there is limited laboratory-based evidence available about survival on soft surfaces, e.g., carpet and upholstered furniture. Several epidemiological reports have suggested soft surfaces may be HuNoV fomites illustrating the importance of conducting a survival study. The three objectives of our research were to demonstrate techniques to characterize soft surfaces, develop a viral elution method for carpet, and characterize the survival of HuNoV surrogates on carpet. These results can be used to improve microbial risk assessments, the development of much-needed soft surface disinfectant, and standardizing protocols for future soft surface studies. PMID:28864657

Evaluation of silver-infused polylactide films for inactivation of Salmonella and feline calicivirus in vitro and on fresh-cut vegetables.

PubMed

Martínez-Abad, A; Ocio, M J; Lagarón, J M; Sánchez, G

2013-03-01

There is a growing trend to develop packaging materials with an active role in guarantying that the quality and safety characteristics of packaged products will remain or improve from preparation throughout shelf-life. In the present study, 0.001-1.0 wt.% silver ions were satisfactorily incorporated into polylactide (PLA) films by a solvent casting technique. Silver migration from the films was measured by voltamperometry and then correlated with its antimicrobial efficacy against Salmonella enterica and feline calicivirus (FCV), a human norovirus surrogate, by using the Japanese industrial standard (JIS Z 2801). The PLA-silver films showed strong antibacterial and antiviral activity in vitro, with increasing effects at higher silver concentrations. Moreover, results show that FCV was less susceptible to silver than Salmonella. When films were applied on food samples, antibacterial and antiviral activity was reduced as compared to in vitro. Antimicrobial activity was very much dependent on the food type and temperature. In lettuce samples incubated at 4 °C during 6 days, 4 log CFU of Salmonella was inactivated for films with 1.0 wt.% and no infectious FCV was reported under the same conditions. On paprika samples, no antiviral effect was seen on FCV infectivity whereas films showed less antibacterial activity on Salmonella. Copyright © 2013 Elsevier B.V. All rights reserved.

Stability of Secondary and Tertiary Structures of Virus-Like Particles Representing Noroviruses: Effects of pH, Ionic Strength, and Temperature and Implications for Adhesion to Surfaces.

PubMed

Samandoulgou, Idrissa; Hammami, Riadh; Morales Rayas, Rocio; Fliss, Ismail; Jean, Julie

2015-11-01

Loss of ordered molecular structure in proteins is known to increase their adhesion to surfaces. The aim of this work was to study the stability of norovirus secondary and tertiary structures and its implications for viral adhesion to fresh foods and agrifood surfaces. The pH, ionic strength, and temperature conditions studied correspond to those prevalent in the principal vehicles of viral transmission (vomit and feces) and in the food processing and handling environment (pasteurization and refrigeration). The structures of virus-like particles representing GI.1, GII.4, and feline calicivirus (FCV) were studied using circular dichroism and intrinsic UV fluorescence. The particles were remarkably stable under most of the conditions. However, heating to 65°C caused losses of β-strand structure, notably in GI.1 and FCV, while at 75°C the α-helix content of GII.4 and FCV decreased and tertiary structures unfolded in all three cases. Combining temperature with pH or ionic strength caused variable losses of structure depending on the particle type. Regardless of pH, heating to pasteurization temperatures or higher would be required to increase GII.4 and FCV adhesion, while either low or high temperatures would favor GI.1 adhesion. Regardless of temperature, increased ionic strength would increase GII.4 adhesion but would decrease GI.1 adhesion. FCV adsorption would be greater at refrigeration, pasteurization, or high temperature combined with a low salt concentration or at a higher NaCl concentration regardless of temperature. Norovirus adhesion mediated by hydrophobic interaction may depend on hydrophobic residues normally exposed on the capsid surface at pH 3, pH 8, physiological ionic strength, and low temperature, while at pasteurization temperatures it may rely more on buried hydrophobic residues exposed upon structural rearrangement. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Removal of adenovirus, calicivirus, and bacteriophages by conventional drinking water treatment.

PubMed

Abbaszadegan, Morteza; Monteiro, Patricia; Nwachuku, Nena; Alum, Absar; Ryu, Hodon

2008-02-01

This study was conducted to evaluate the removal of adenovirus, feline calicivirus (FCV), and bacteriophages MS-2, fr, PRD-1, and Phi X-174 during conventional drinking water treatment using ferric chloride as a coagulant. Adenovirus and FCV were removed to a greater extent than PRD-1 and Phi X-174, indicating that these bacteriophages may be appropriate surrogates for both adenovirus and FCV. Of the four bacteriophages studied in the pilot plant, MS-2 was removed to the greatest extent (5.1 log), followed by fr (4.9 log), PRD-1 (3.5 log), and Phi X-174 (1.3 log). The virus removal trend in the pilot-scale testing was similar to the bench-scale testing; however, the bench-scale testing seemed to provide a conservative estimate of the pilot plant performance. In the pilot-scale testing, MS-2 and fr were removed with the greatest efficiency during filtration, whereas PRD-1 and Phi X-174 showed the greatest removal during sedimentation.

Effects of maternally-derived antibodies on serologic responses to vaccination in kittens.

PubMed

Digangi, Brian A; Levy, Julie K; Griffin, Brenda; Reese, Michael J; Dingman, Patricia A; Tucker, Sylvia J; Dubovi, Edward J

2012-02-01

The optimal vaccination protocol to induce immunity in kittens with maternal antibodies is unknown. The objective of this study was to determine the effects of maternally-derived antibody (MDA) on serologic responses to vaccination in kittens. Vaccination with a modified live virus (MLV) product was more effective than an inactivated (IA) product at inducing protective antibody titers (PAT) against feline panleukopenia virus (FPV). IA vaccination against feline herpesvirus-1 (FHV) and feline calicivirus (FCV) was more effective in the presence of low MDA than high MDA. Among kittens with low MDA, MLV vaccination against FCV was more effective than IA vaccination. A total of 15%, 44% and 4% of kittens had insufficient titers against FPV, FHV and FCV, respectively, at 17 weeks of age. Serologic response to vaccination of kittens varies based on vaccination type and MDA level. In most situations, MLV vaccination should be utilized and protocols continued beyond 14 weeks of age to optimize response by all kittens.

Recovery Optimization and Survival of the Human Norovirus Surrogates Feline Calicivirus and Murine Norovirus on Carpet.

PubMed

Buckley, David; Fraser, Angela; Huang, Guohui; Jiang, Xiuping

2017-11-15

Carpets have been implicated in prolonged and reoccurring outbreaks of human noroviruses (HuNoV), the leading cause of acute gastroenteritis worldwide. Viral recovery from environmental surfaces, such as carpet, remains undeveloped. Our aim was to determine survival of HuNoV surrogates on an understudied environmental surface, carpet. First, we measured the zeta potential and absorption capacity of wool and nylon carpet fibers, we then developed a minispin column elution (MSC) method, and lastly we characterized the survival of HuNoV surrogates, feline calicivirus (FCV) and murine norovirus (MNV), over 60 days under 30 and 70% relative humidity (RH) on two types of carpet and one glass surface. Carpet surface charge was negative between relevant pH values (i.e., pH 7 to 9). In addition, wool could absorb approximately two times more liquid than nylon. The percent recovery efficiency obtained by the MSC method ranged from 4.34 to 20.89% and from 30.71 to 54.14% for FCV and MNV on carpet fibers, respectively, after desiccation. Overall, elution buffer type did not significantly affect recovery. Infectious FCV or MNV survived between <1 and 15 or between 3 and 15 days, respectively. However, MNV survived longer under some conditions and at significantly ( P < 0.05) higher titers compared to FCV. Albeit, surrogates followed similar survival trends, i.e., both survived longest on wool then nylon and glass, while 30% RH provided a more hospitable environment compared to 70% RH. Reverse transcription-quantitative PCR signals for both surrogates were detectable for the entire study, but FCV genomic copies experienced significantly higher reductions (<3.80 log 10 copies) on all surfaces compared to MNV (<1.10 log 10 copies). IMPORTANCE Human noroviruses (HuNoV) are the leading cause of acute gastroenteritis worldwide. Classical symptoms of illness include vomiting and diarrhea which could lead to severe dehydration and death. HuNoV are transmitted by the fecal-oral or vomitus-oral route via person-to-person contact, food, water, and/or environmental surfaces. Published laboratory-controlled studies have documented the environmental stability of HuNoV on hard surfaces, but there is limited laboratory-based evidence available about survival on soft surfaces, e.g., carpet and upholstered furniture. Several epidemiological reports have suggested soft surfaces may be HuNoV fomites illustrating the importance of conducting a survival study. The three objectives of our research were to demonstrate techniques to characterize soft surfaces, develop a viral elution method for carpet, and characterize the survival of HuNoV surrogates on carpet. These results can be used to improve microbial risk assessments, the development of much-needed soft surface disinfectant, and standardizing protocols for future soft surface studies. Copyright © 2017 American Society for Microbiology.

Thermal Inactivation Kinetics of Human Norovirus Surrogates and Hepatitis A Virus in Turkey Deli Meat.

PubMed

Bozkurt, Hayriye; D'Souza, Doris H; Davidson, P Michael

2015-07-01

Human noroviruses (HNoV) and hepatitis A virus (HAV) have been implicated in outbreaks linked to the consumption of presliced ready-to-eat deli meats. The objectives of this research were to determine the thermal inactivation kinetics of HNoV surrogates (murine norovirus 1 [MNV-1] and feline calicivirus strain F9 [FCV-F9]) and HAV in turkey deli meat, compare first-order and Weibull models to describe the data, and calculate Arrhenius activation energy values for each model. The D (decimal reduction time) values in the temperature range of 50 to 72°C calculated from the first-order model were 0.1 ± 0.0 to 9.9 ± 3.9 min for FCV-F9, 0.2 ± 0.0 to 21.0 ± 0.8 min for MNV-1, and 1.0 ± 0.1 to 42.0 ± 5.6 min for HAV. Using the Weibull model, the tD = 1 (time to destroy 1 log) values for FCV-F9, MNV-1, and HAV at the same temperatures ranged from 0.1 ± 0.0 to 11.9 ± 5.1 min, from 0.3 ± 0.1 to 17.8 ± 1.8 min, and from 0.6 ± 0.3 to 25.9 ± 3.7 min, respectively. The z (thermal resistance) values for FCV-F9, MNV-1, and HAV were 11.3 ± 2.1°C, 11.0 ± 1.6°C, and 13.4 ± 2.6°C, respectively, using the Weibull model. The z values using the first-order model were 11.9 ± 1.0°C, 10.9 ± 1.3°C, and 12.8 ± 1.7°C for FCV-F9, MNV-1, and HAV, respectively. For the Weibull model, estimated activation energies for FCV-F9, MNV-1, and HAV were 214 ± 28, 242 ± 36, and 154 ± 19 kJ/mole, respectively, while the calculated activation energies for the first-order model were 181 ± 16, 196 ± 5, and 167 ± 9 kJ/mole, respectively. Precise information on the thermal inactivation of HNoV surrogates and HAV in turkey deli meat was generated. This provided calculations of parameters for more-reliable thermal processes to inactivate viruses in contaminated presliced ready-to-eat deli meats and thus to reduce the risk of foodborne illness outbreaks. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Thermal Inactivation Kinetics of Human Norovirus Surrogates and Hepatitis A Virus in Turkey Deli Meat

PubMed Central

Bozkurt, Hayriye; Davidson, P. Michael

2015-01-01

Human noroviruses (HNoV) and hepatitis A virus (HAV) have been implicated in outbreaks linked to the consumption of presliced ready-to-eat deli meats. The objectives of this research were to determine the thermal inactivation kinetics of HNoV surrogates (murine norovirus 1 [MNV-1] and feline calicivirus strain F9 [FCV-F9]) and HAV in turkey deli meat, compare first-order and Weibull models to describe the data, and calculate Arrhenius activation energy values for each model. The D (decimal reduction time) values in the temperature range of 50 to 72°C calculated from the first-order model were 0.1 ± 0.0 to 9.9 ± 3.9 min for FCV-F9, 0.2 ± 0.0 to 21.0 ± 0.8 min for MNV-1, and 1.0 ± 0.1 to 42.0 ± 5.6 min for HAV. Using the Weibull model, the tD = 1 (time to destroy 1 log) values for FCV-F9, MNV-1, and HAV at the same temperatures ranged from 0.1 ± 0.0 to 11.9 ± 5.1 min, from 0.3 ± 0.1 to 17.8 ± 1.8 min, and from 0.6 ± 0.3 to 25.9 ± 3.7 min, respectively. The z (thermal resistance) values for FCV-F9, MNV-1, and HAV were 11.3 ± 2.1°C, 11.0 ± 1.6°C, and 13.4 ± 2.6°C, respectively, using the Weibull model. The z values using the first-order model were 11.9 ± 1.0°C, 10.9 ± 1.3°C, and 12.8 ± 1.7°C for FCV-F9, MNV-1, and HAV, respectively. For the Weibull model, estimated activation energies for FCV-F9, MNV-1, and HAV were 214 ± 28, 242 ± 36, and 154 ± 19 kJ/mole, respectively, while the calculated activation energies for the first-order model were 181 ± 16, 196 ± 5, and 167 ± 9 kJ/mole, respectively. Precise information on the thermal inactivation of HNoV surrogates and HAV in turkey deli meat was generated. This provided calculations of parameters for more-reliable thermal processes to inactivate viruses in contaminated presliced ready-to-eat deli meats and thus to reduce the risk of foodborne illness outbreaks. PMID:25956775

Capsid functions of inactivated human picornaviruses and feline calicivirus.

PubMed

Nuanualsuwan, Suphachai; Cliver, Dean O

2003-01-01

The exceptional stability of enteric viruses probably resides in their capsids. The capsid functions of inactivated human picornaviruses and feline calicivirus (FCV) were determined. Viruses were inactivated by UV, hypochlorite, high temperature (72 degrees C), and physiological temperature (37 degrees C), all of which are pertinent to transmission via food and water. Poliovirus (PV) and hepatitis A virus (HAV) are transmissible via water and food, and FCV is the best available surrogate for the Norwalk-like viruses, which are leading causes of food-borne and waterborne disease in the United States. The capsids of all 37 degrees C-inactivated viruses still protected the viral RNA against RNase, even in the presence of proteinase K, which contrasted with findings with viruses inactivated at 72 degrees C. The loss of ability of the virus to attach to homologous cell receptors was universal, regardless of virus type and inactivation method, except for UV-inactivated HAV, and so virus inactivation was almost always accompanied by the loss of virus attachment. Inactivated HAV and FCV were captured by homologous antibodies. However, inactivated PV type 1 (PV-1) was not captured by homologous antibody and 37 degrees C-inactivated PV-1 was only partially captured. The epitopes on the capsids of HAV and FCV are evidently discrete from the receptor attachment sites, unlike those of PV-1. These findings indicate that the primary target of UV, hypochlorite, and 72 degrees C inactivation is the capsid and that the target of thermal inactivation (37 degrees C versus 72 degrees C) is temperature dependent.

A comparison of hand washing techniques to remove Escherichia coli and caliciviruses under natural or artificial fingernails.

PubMed

Lin, Chia-Min; Wu, Fone-Mao; Kim, Hoi-Kyung; Doyle, Michael P; Michael, Barry S; Williams, L Keoki

2003-12-01

Compared with other parts of the hand, the area beneath fingernails harbors the most microorganisms and is most difficult to clean. Artificial fingernails, which are usually long and polished, reportedly harbor higher microbial populations than natural nails. Hence, the efficacy of different hand washing methods for removing microbes from natural and artificial fingernails was evaluated. Strains of nonpathogenic Escherichia coli JM109 and feline calicivirus (FCV) strain F9 were used as bacterial and viral indicators, respectively. Volunteers with artificial or natural nails were artificially contaminated with ground beef containing E. coli JM109 or artificial feces containing FCV. Volunteers washed their hands with tap water, regular liquid soap, antibacterial liquid soap, alcohol-based hand sanitizer gel, regular liquid soap followed by alcohol gel, or regular liquid soap plus a nailbrush. The greatest reduction of inoculated microbial populations was obtained by washing with liquid soap plus a nailbrush, and the least reduction was obtained by rubbing hands with alcohol gel. Lower but not significantly different (P > 0.05) reductions of E. coli and FCV counts were obtained from beneath artificial than from natural fingernails. However, significantly (P < or = 0.05) higher E. coli and FCV counts were recovered from hands with artificial nails than from natural nails before and after hand washing. In addition, microbial cell numbers were correlated with fingernail length, with greater numbers beneath fingernails with longer nails. These results indicate that best practices for fingernail sanitation of food handlers are to maintain short fingernails and scrub fingernails with soap and a nailbrush when washing hands.

A Randomized Male Tolerance Study of Dapivirine Gel Following Multiple Topical Penile Exposures (MTN 012/IPM 010)

PubMed Central

Hoesley, Craig; Carballo-Diéguez, Alex; Hendrix, Craig W.; Husnik, Marla; Levy, Lisa; Hall, Wayne; Soto-Torres, Lydia; Nel, Annalene M.

2014-01-01

Abstract Dapivirine (DPV) is a nonnucleoside reverse transcriptase inhibitor with a favorable safety profile following vaginal application. A penile tolerance study was conducted prior to further development of DPV as a candidate vaginal microbicide. Twenty-four circumcised and 24 uncircumcised (N=48) healthy HIV-negative male participants aged 18 years or older were randomized 2:1:1 to apply DPV 0.05% gel, matched placebo gel, or universal placebo gel, respectively, to their penis once daily for 7 sequential days. The safety, acceptability, and pharmacokinetic profile of DPV 0.05% gel were assessed by the presence of Grade 2 or higher genitourinary adverse events (AEs) and systemic AEs, a behavioral questionnaire, and pharmacokinetic plasma blood draw, respectively, at the final clinic visit (FCV). There were no Grade 2 genitourinary AEs in 47 participants completing the FCV. One participant in the DPV arm failed to attend the FCV. There were 13 AEs reported; all were Grade 1 except one Grade 2 corneal laceration unrelated to study product. Participants liked the gel to a moderate extent, yet 72% reported they would be “very likely” to use a gel like the one they used in the study every time they have intercourse. DPV was detectable in plasma in all 23 DPV arm study participants at the FCV. On average, the circumcised participants' DPV concentrations were 54% of those in uncircumcised participants (p=0.07). Topical seven-day penile application of DPV 0.05% gel was locally and systemically safe, was acceptable to male participants, and resulted in systemic exposure to the drug. PMID:24070431

A randomized male tolerance study of dapivirine gel following multiple topical penile exposures (MTN 012/IPM 010).

PubMed

Cranston, Ross D; Hoesley, Craig; Carballo-Diéguez, Alex; Hendrix, Craig W; Husnik, Marla; Levy, Lisa; Hall, Wayne; Soto-Torres, Lydia; Nel, Annalene M

2014-02-01

Dapivirine (DPV) is a nonnucleoside reverse transcriptase inhibitor with a favorable safety profile following vaginal application. A penile tolerance study was conducted prior to further development of DPV as a candidate vaginal microbicide. Twenty-four circumcised and 24 uncircumcised (N=48) healthy HIV-negative male participants aged 18 years or older were randomized 2:1:1 to apply DPV 0.05% gel, matched placebo gel, or universal placebo gel, respectively, to their penis once daily for 7 sequential days. The safety, acceptability, and pharmacokinetic profile of DPV 0.05% gel were assessed by the presence of Grade 2 or higher genitourinary adverse events (AEs) and systemic AEs, a behavioral questionnaire, and pharmacokinetic plasma blood draw, respectively, at the final clinic visit (FCV). There were no Grade 2 genitourinary AEs in 47 participants completing the FCV. One participant in the DPV arm failed to attend the FCV. There were 13 AEs reported; all were Grade 1 except one Grade 2 corneal laceration unrelated to study product. Participants liked the gel to a moderate extent, yet 72% reported they would be "very likely" to use a gel like the one they used in the study every time they have intercourse. DPV was detectable in plasma in all 23 DPV arm study participants at the FCV. On average, the circumcised participants' DPV concentrations were 54% of those in uncircumcised participants (p=0.07). Topical seven-day penile application of DPV 0.05% gel was locally and systemically safe, was acceptable to male participants, and resulted in systemic exposure to the drug.

A PEMFC hybrid electric vehicle real time control system

NASA Astrophysics Data System (ADS)

Sun, Hongqiao

In recent years, environmental friendly technologies and alternative energy solutions have drawn a lot of public attentions due to global energy crisis and pollution issues. Fuel cell (FC), a technology invented almost at the same time as the internal combustion (IC) engine, is now the focus of the automotive industry again. The fuel cell vehicle (FCV) has zero emission and its efficiency is significantly higher than the conventional IC engine power vehicles. Among a variety of FCV technologies, proton exchange membrane (PEM) FC vehicle appears to be far more attractive and mature. The prototype PEMFC vehicle has been developed and demonstrated to the public by nearly all the major automotive manufacturers in recent years. However, to the interest of the public research, publications and documentations on the PEMFC vehicle technology are rarely available due to its proprietary nature, which essentially makes it a secured technology. This dissertation demonstrates a real world application of a PEMFC hybrid electric vehicle. Through presenting the vehicle design concept, developing the real time control system and generating generic operation principles, this dissertation targets at establishing the public knowledge base on this new technology. A complete PEMFC hybrid electric vehicle design, including vehicle components layout, process flow diagram, real time control system architecture, subsystem structures and control algorithms, is presented in order to help understand the whole vehicle system. The design concept is validated through the vehicle demonstration. Generic operating principles are established along with the validation process, which helps populate this emerging technology. Thereafter, further improvements and future research directions are discussed.

Options for refuelling hydrogen fuel cell vehicles in Italy

NASA Astrophysics Data System (ADS)

Mercuri, R.; Bauen, A.; Hart, D.

Hydrogen fuel cell vehicle (H 2 FCV) trials are taking place in a number of cities around the world. In Italy, Milan and Turin are the first to have demonstration projects involving hydrogen-fuelled vehicles, in part to satisfy increasing consumer demand for improved environmental performance. The Italian transport plan specifically highlights the potential for FCVs to enter into the marketplace from around 2005. A scenario for FCV penetration into Italy, developed using projected costs for FCV and hydrogen fuel, suggests that by 2015, 2 million Italian cars could be powered by fuel cells. By 2030, 60% of the parc could be FCVs. To develop an infrastructure to supply these vehicles, a variety of options is considered. Large-scale steam reforming, on-site reforming and electrolysis options are analysed, with hydrogen delivered both in liquid and gaseous form. Assuming mature technologies, with over 10,000 units produced, on-site steam reforming provides the most economic hydrogen supply to the consumer, at US 2.6/kg. However, in the early stages of the infrastructure development there is a clear opportunity for on-site electrolysis and for production of hydrogen at centralised facilities, with delivery in the form of liquid hydrogen. This enables additional flexibility, as the hydrogen may also be used for fuel refining or for local power generation. In the current Italian context, energy companies could have a significant role to play in developing a hydrogen infrastructure. The use of hydrogen FCVs can substantially reduce emissions of regulated pollutants and greenhouse gases. Using externality costs for regulated pollutants, it is estimated that the use of hydrogen fuel cell buses in place of 5% of diesel buses in Milan could avoid US 2 million per year in health costs. The addition of even very low externality costs to fuel prices makes the use of untaxed hydrogen in buses and cars, which is slightly more expensive for the motorist than untaxed gasoline or diesel, competitive on a social cost basis.

Naturally occurring flavonoids against human norovirus surrogates.

PubMed

Su, Xiaowei; D'Souza, Doris H

2013-06-01

Naturally occurring plant-derived flavonoids are reported to have antibacterial, antiviral, and pharmacological activities. The objectives of this study were to determine the antiviral effects of four flavonoids (myricetin, L-epicatechin, tangeretin, and naringenin) on the infectivity of food borne norovirus surrogates after 2 h at 37 °C. The lab-culturable surrogates, feline calicivirus (FCV-F9) at titers of ~7 log₁₀ PFU/ml (high titer) or ~5 log₁₀ PFU/ml (low titer) and murine norovirus (MNV-1) at ~5 log₁₀ PFU/ml, were mixed with equal volumes of myricetin, L-epicatechin, tangeretin, or naringenin at concentrations of 0.5 or 1 mM, and incubated for 2 h at 37 °C. Treatments of viruses were neutralized in cell culture medium containing 10 % heat-inactivated fetal bovine serum, serially diluted, and plaque assayed. Each treatment was replicated thrice and assayed in duplicate. FCV-F9 (low titer) was not found to be reduced by tangeretin or naringenin, but was reduced to undetectable levels by myricetin at both concentrations. Low titer FCV-F9 was also decreased by 1.40 log₁₀ PFU/ml with L-epicatechin at 0.5 mM. FCV-F9 at high titers was decreased by 3.17 and 0.72 log₁₀ PFU/ml with myricetin and L-epicatechin at 0.5 mM, and 1.73 log10 PFU/ml with myricetin at 0.25 mM, respectively. However, MNV-1 showed no significant inactivation by the four tested treatments. The antiviral effects of the tested flavonoids are dependent on the virus type, titer, and dose. Further research will focus on understanding the antiviral mechanism of myricetin and L-epicatechin.

Life cycle analysis of vehicles powered by a fuel cell and by internal combustion engine for Canada

NASA Astrophysics Data System (ADS)

Zamel, Nada; Li, Xianguo

The transportation sector is responsible for a great percentage of the greenhouse gas emissions as well as the energy consumption in the world. Canada is the second major emitter of carbon dioxide in the world. The need for alternative fuels, other than petroleum, and the need to reduce energy consumption and greenhouse gases emissions are the main reasons behind this study. In this study, a full life cycle analysis of an internal combustion engine vehicle (ICEV) and a fuel cell vehicle (FCV) has been carried out. The impact of the material and fuel used in the vehicle on energy consumption and carbon dioxide emissions is analyzed for Canada. The data collected from the literature shows that the energy consumption for the production of 1 kg of aluminum is five times higher than that of 1 kg of steel, although higher aluminum content makes vehicles lightweight and more energy efficient during the vehicle use stage. Greenhouse gas regulated emissions and energy use in transportation (GREET) software has been used to analyze the fuel life cycle. The life cycle of the fuel consists of obtaining the raw material, extracting the fuel from the raw material, transporting, and storing the fuel as well as using the fuel in the vehicle. Four different methods of obtaining hydrogen were analyzed; using coal and nuclear power to produce electricity and extraction of hydrogen through electrolysis and via steam reforming of natural gas in a natural gas plant and in a hydrogen refueling station. It is found that the use of coal to obtain hydrogen generates the highest emissions and consumes the highest energy. Comparing the overall life cycle of an ICEV and a FCV, the total emissions of an FCV are 49% lower than an ICEV and the energy consumption of FCV is 87% lower than that of ICEV. Further, CO 2 emissions during the hydrogen fuel production in a central plant can be easily captured and sequestrated. The comparison carried out in this study between FCV and ICEV is extended to the use of recycled material. It is found that using 100% recycled material can reduce energy consumption by 45% and carbon dioxide emissions by 42%, mainly due to the reduced use of electricity during the manufacturing of the material.

Large-scale risk assessment of polycyclic aromatic hydrocarbons in shoreline sediments from Saudi Arabia: environmental legacy after twelve years of the Gulf war oil spill.

PubMed

Bejarano, Adriana C; Michel, Jacqueline

2010-05-01

A large-scale assessment of polycyclic aromatic hydrocarbons (PAHs) from the 1991 Gulf War oil spill was performed for 2002-2003 sediment samples (n = 1679) collected from habitats along the shoreline of Saudi Arabia. Benthic sediment toxicity was characterized using the Equilibrium Partitioning Sediment Benchmark Toxic Unit approach for 43 PAHs (ESBTU(FCV,43)). Samples were assigned to risk categories according to ESBTU(FCV,43) values: no-risk (< or = 1), low (>1 - < or = 2), low-medium (>2 - < or = 3), medium (>3 - < or = 5) and high-risk (>5). Sixty seven percent of samples had ESBTU(FCV,43) > 1 indicating potential adverse ecological effects. Sediments from the 0-30 cm layer from tidal flats, and the >30 - <60 cm layer from heavily oiled halophytes and mangroves had high frequency of high-risk samples. No-risk samples were characterized by chrysene enrichment and depletion of lighter molecular weight PAHs, while high-risk samples showed little oil weathering and PAH patterns similar to 1993 samples. North of Safaniya sediments were not likely to pose adverse ecological effects contrary to sediments south of Tanaqib. Landscape and geomorphology has played a role on the distribution and persistence in sediments of oil from the Gulf War. Copyright 2009 Elsevier Ltd. All rights reserved.

Aqueous Extracts of Hibiscus sabdariffa Calyces Decrease Hepatitis A Virus and Human Norovirus Surrogate Titers.

PubMed

Joshi, Snehal S; Dice, Lezlee; D'Souza, Doris H

2015-12-01

Hibiscus sabdariffa extract is known to have antioxidant, anti-diabetic, and antimicrobial properties. However, their effects against foodborne viruses are currently unknown. The objective of this study was to determine the antiviral effects of aqueous extracts of H. sabdariffa against human norovirus surrogates (feline calicivirus (FCV-F9) and murine norovirus (MNV-1)) and hepatitis A virus (HAV) at 37 °C over 24 h. Individual viruses (~5 log PFU/ml) were incubated with 40 or 100 mg/ml of aqueous hibiscus extract (HE; pH 3.6), protocatechuic acid (PCA; 3 or 6 mg/ml, pH 3.6), ferulic acid (FA; 0.5 or 1 mg/ml; pH 4.0), malic acid (10 mM; pH 3.0), or phosphate buffered saline (pH 7.2 as control) at 37 °C over 24 h. Each treatment was replicated thrice and plaque assayed in duplicate. FCV-F9 titers were reduced to undetectable levels after 15 min with both 40 and 100 mg/ml HE. MNV-1 was reduced by 1.77 ± 0.10 and 1.88 ± 0.12 log PFU/ml after 6 h with 40 and 100 mg/ml HE, respectively, and to undetectable levels after 24 h by both concentrations. HAV was reduced to undetectable levels by both HE concentrations after 24 h. PCA at 3 mg/ml reduced FCV-F9 titers to undetectable levels after 6 h, MNV-1 by 0.53 ± 0.01 log PFU/ml after 6 h, and caused no significant change in HAV titers. FA reduced FCV-F9 to undetectable levels after 3 h and MNV-1 and HAV after 24 h. Transmission electron microscopy showed no conclusive results. The findings suggest that H. sabdariffa extracts have potential to prevent foodborne viral transmission.

Stability of and Attachment to Lettuce by a Culturable Porcine Sapovirus Surrogate for Human Caliciviruses

PubMed Central

Zhang, Zhenwen

2012-01-01

Human noroviruses (HuNoVs) are the leading cause of food-borne illness, accounting for 58% of U.S. cases. Because HuNoVs are unculturable, surrogates are needed to investigate transmission routes and evaluate disinfection methods. However, the current surrogates, feline calicivirus (FCV) and murine NoV (MNV), are less tolerant than HuNoVs to acid and chlorine, respectively. Porcine sapovirus (SaV) is the only culturable enteropathogenic calicivirus. In this study, the resistance of SaV to physicochemical treatments was compared to that of HuNoVs (by reverse transcription-PCR), FCV, and MNV (by infectivity assays). Sapovirus and HuNoV (viral RNA) showed similar resistances to heat (56°C) and to different concentrations of chlorine. However, SaV was more resistant than HuNoVs to ethanol treatment (60% and 70%). Like HuNoVs, SaV was stable at pH 3.0 to 8.0, with a <1.0 log10 50% tissue culture infective dose (TCID50) reduction at pH 3.0 compared to the value for pH 4.0 to 8.0. SaV and MNV showed similar resistances, and both were more resistant than FCV to heat inactivation (56°C). FCV was more resistant than MNV and SaV to ethanol, and all three viruses showed similar resistances to treatment with low concentrations of chlorine for 1 min. Those results indicate that SaV is a promising surrogate for HuNoVs. Next, we used SaV as a surrogate to examine virus attachment to lettuce at different pHs. Sapovirus attached to lettuce leaves significantly at its capsid isoelectric point (pH 5.0), and the attached viral particles remained infectious on lettuce after 1 week of storage at 4°C. The culturable SaV is a good surrogate for studying HuNoV contamination and transmission in leafy greens and potential disinfectants. PMID:22447610

Prevention the spread of norovirus infection on airborne route by using Plasma Assisted Catalytic Technology (PACT) device.

PubMed

Tanaka, Yoshimoto; Fujino, Kan; Larkins, Gerald Andrew; Osawa, Atsushi; Hayashi, Yuji; Taharaguchi, Satoshi

2018-04-30

Zoonosis becomes a popular word. Highly pathogenic influenza virus (HPI), Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) recently occurred at around Africa, Meddle-East and South-East Asia area, whose virus is classified as airborne. Sterilization capability was investigated by using chemical reactor of PACT device. Test on airborne infection was carried out by Feline Calicivirus Vaccine (FCV) strain F9, which is also surrogated human norovirus. It was found that PACT device could sterilize instantly FCV when passing through the plasma space of PACT device. Sterilization rate may be more than 99.99% (below the detection limit). This result may be available to sterilize various virus including human norovirus and airborne-infectious microorganisms.

Serological Detection of Viral Infections in Captive Wild Cats from Costa Rica

PubMed Central

Blanco, Kinndle; Peña, Roberto; Hernández, Carmen; Jiménez, Mauricio; Araya, Luis Nazario; Romero, Juan José; Dolz, Gaby

2011-01-01

Serum samples from a total of 44 wildcats, 28 margays (Leopardus wiedii), 10 ocelots (Leopardus pardalis), four jaguaroundis (Herpailurus yaguaroundi), one oncilla (Leopardus tigrina), and one jaguar (Panthera onca) were obtained between January 2001 and August 2002 from the Profelis Centre for rehabilitation of wild felids, located in the northwestern region of Costa Rica. Forty three samples were tested for antibodies against feline immunodeficiency virus (FIV) and p27 antigen of feline leukemia virus (FeLV), 42 samples for antibodies against feline parvovirus (FPV), and 30 for antibodies against feline calicivirus (FCV). None of the samples contained detectable antibodies against FIV or p27 antigen of FeLV, all samples contained antibodies against FPV, and one sample contained antibodies against FCV. PMID:21547230

Serological detection of viral infections in captive wild cats from costa rica.

PubMed

Blanco, Kinndle; Peña, Roberto; Hernández, Carmen; Jiménez, Mauricio; Araya, Luis Nazario; Romero, Juan José; Dolz, Gaby

2011-04-03

Serum samples from a total of 44 wildcats, 28 margays (Leopardus wiedii), 10 ocelots (Leopardus pardalis), four jaguaroundis (Herpailurus yaguaroundi), one oncilla (Leopardus tigrina), and one jaguar (Panthera onca) were obtained between January 2001 and August 2002 from the Profelis Centre for rehabilitation of wild felids, located in the northwestern region of Costa Rica. Forty three samples were tested for antibodies against feline immunodeficiency virus (FIV) and p27 antigen of feline leukemia virus (FeLV), 42 samples for antibodies against feline parvovirus (FPV), and 30 for antibodies against feline calicivirus (FCV). None of the samples contained detectable antibodies against FIV or p27 antigen of FeLV, all samples contained antibodies against FPV, and one sample contained antibodies against FCV.

Efficacy of Tissue Culture in Virus Elimination from Caprifig and Female Fig Varieties (Ficus carica L.).

PubMed

Bayoudh, Chokri; Elair, Manel; Labidi, Rahma; Majdoub, Afifa; Mahfoudhi, Naima; Mars, Messaoud

2017-06-01

Fig mosaic disease (FMD) is a viral disease that spreads in all Tunisian fig ( Ficus carica L.) orchards. RT-PCR technique was applied to leaf samples of 29 fig accessions of 15 fig varieties from the fig germplasm collection of High Agronomic Institute (I.S.A) of Chatt-Mariem, to detect viruses associated to FMD. Analysis results show that 65.5% of the accessions (19/29) and 80.0% (12/15) of the fig varieties are infected by FMD-associated viruses. From all fig accessions, 41.4% of them are with single infection (one virus) and 24.1% are with multi-infections (2 virus and more). Viruses infecting fig leaf samples are Fig mosaic virus (FMV) (20.7%), Fig milde-mottle-associated virus (FMMaV) (17.25%), Fig fleck associated virus (FFkaV) (3.45%), and Fig cryptic virus (FCV) (55.17%). A reliable protocol for FCV and FMMaV elimination from 4 local fig varieties Zidi (ZDI), Soltani (SNI), Bither Abiadh (BA), and Assafri (ASF) via in vitro culture of 3 meristem sizes was established and optimized. With this protocol, global sanitation rates of 79.46%, 65.55%, 68.75%, and 70.83% respectively for ZDI, SNI, BA, and ASF are achieved. For all sanitized varieties, the effectiveness of meristem culture for the elimination of FCV and FMMaV viruses was related to meristem size. Meristem size 0.5 mm provides the highest sanitation rates ranging from 70% to 90%.

Efficacy of Tissue Culture in Virus Elimination from Caprifig and Female Fig Varieties (Ficus carica L.)

PubMed Central

Bayoudh, Chokri; Elair, Manel; Labidi, Rahma; Majdoub, Afifa; Mahfoudhi, Naima; Mars, Messaoud

2017-01-01

Fig mosaic disease (FMD) is a viral disease that spreads in all Tunisian fig (Ficus carica L.) orchards. RT-PCR technique was applied to leaf samples of 29 fig accessions of 15 fig varieties from the fig germplasm collection of High Agronomic Institute (I.S.A) of Chatt-Mariem, to detect viruses associated to FMD. Analysis results show that 65.5% of the accessions (19/29) and 80.0% (12/15) of the fig varieties are infected by FMD-associated viruses. From all fig accessions, 41.4% of them are with single infection (one virus) and 24.1% are with multi-infections (2 virus and more). Viruses infecting fig leaf samples are Fig mosaic virus (FMV) (20.7%), Fig milde-mottle-associated virus (FMMaV) (17.25%), Fig fleck associated virus (FFkaV) (3.45%), and Fig cryptic virus (FCV) (55.17%). A reliable protocol for FCV and FMMaV elimination from 4 local fig varieties Zidi (ZDI), Soltani (SNI), Bither Abiadh (BA), and Assafri (ASF) via in vitro culture of 3 meristem sizes was established and optimized. With this protocol, global sanitation rates of 79.46%, 65.55%, 68.75%, and 70.83% respectively for ZDI, SNI, BA, and ASF are achieved. For all sanitized varieties, the effectiveness of meristem culture for the elimination of FCV and FMMaV viruses was related to meristem size. Meristem size 0.5 mm provides the highest sanitation rates ranging from 70% to 90%. PMID:28592947

Prevalence of selected infectious disease agents in stray cats in Catalonia, Spain

PubMed Central

Ravicini, Sara; Pastor, Josep; Hawley, Jennifer; Brewer, Melissa; Castro-López, Jorge; Beall, Melissa; Lappin, Michael R

2016-01-01

Objectives The objective of the current study was to investigate the prevalence rates of the following infectious agents in 116 stray cats in the Barcelona area of Spain: Anaplasma phagocytophilum, Bartonella species, Borrelia burgdorferi, Chlamydia felis, Dirofilaria immitis, Ehrlichia species, feline calicivirus (FCV), feline herpesvirus-1 (FHV-1), feline leukaemia virus (FeLV), feline immunodeficiency virus (FIV), haemoplasmas, Mycoplasma species and Rickettsia species. Methods Serum antibodies were used to estimate the prevalence of exposure to A phagocytophilum, Bartonella species, B burgdorferi, Ehrlichia species and FIV; serum antigens were used to assess for infection by D immitis and FeLV; and molecular assays were used to amplify nucleic acids of Anaplasma species, Bartonella species, C felis, D immitis, Ehrlichia species, FCV, FHV-1, haemoplasmas, Mycoplasma species and Rickettsia species from blood and nasal or oral swabs. Results Of the 116 cats, 63 (54.3%) had evidence of infection by Bartonella species, FeLV, FIV or a haemoplasma. Anaplasma species, Ehrlichia species or Rickettsia species DNA was not amplified from these cats. A total of 18/116 cats (15.5%) were positive for FCV RNA (six cats), Mycoplasma species DNA (six cats), FHV-1 DNA (three cats) or C felis DNA (three cats). Conclusions and relevance This study documents that shelter cats in Catalonia are exposed to many infectious agents with clinical and zoonotic significance, and that flea control is indicated for cats in the region. PMID:28491415

Evaluation of the Persistence of Infectious Human Noroviruses on Food Surfaces by Using Real-Time Nucleic Acid Sequence-Based Amplification▿

PubMed Central

Lamhoujeb, Safaa; Fliss, Ismail; Ngazoa, Solange E.; Jean, Julie

2008-01-01

Noroviruses (NoV) are the major cause of nonbacterial gastroenteritis. However, there is no published study to ascertain their survival on foodstuffs which are directly related to human health risk. In the present study, we developed a rapid, simple, and sensitive real-time nucleic acid sequence-based amplification (NASBA) combined with an enzymatic treatment for distinguishing infectious from noninfectious human NoV. The developed method was validated using spiked ready-to-eat food samples. When feline calicivirus (FCV) was used as a NoV surrogate in the preliminary assays, it appeared more sensitive to heat inactivation and enzymatic pretreatment than the human NoV. This suggests that FCV may not be an ideal model for studying NoV. Our results reveal clearly that the developed enzymatic pretreatment/real-time NASBA combination successfully distinguished the infectious from heat-inactivated NoV. Moreover, we demonstrate that NoV survived for at least 10 days on refrigerated ready-to-eat foods, such as lettuce and turkey. However, the survival rate was higher on turkey than on lettuce, probably because of their different surface natures. The approach developed in this study may be suitable for more in-depth studies of the persistence and inactivation of human NoV and may be applied to other nonculturable RNA viruses. Moreover, the evaluation of infectious NoV survival provided valuable information concerning its persistence on ready-to-eat food. PMID:18378643

Hot topics in alkaline exchange membrane fuel cells

NASA Astrophysics Data System (ADS)

Serov, Alexey; Zenyuk, Iryna V.; Arges, Christopher G.; Chatenet, Marian

2018-01-01

The tremendous progress from the first discovery of fuel cell principles by Sir William Robert Grove in 1839 [1] and independent observation of electricity generated in electrochemical reaction of hydrogen and air by a Swiss scientist Christian F. Shoenbein [2] to the recent breakthroughs in the fuel cell field resulted in the appearance of this clean energy technology around us. Indeed, fuel cell technology undoubtedly has entered into our life with the first introduction of Toyota Mirai Fuel Cell Vehicle (FCV) by Toyota Motor Co. in December of 2014 [3,4]. This FCV is commercially available and can be purchased in several countries. However, its sticker price of 57,500 substantially limits the number of customers that can purchase it. There are numerous factors that contribute to the high cost of fuel cell stack, however the price of platinum and platinum alloys is the main contributor [5].

Fricative-stop coarticulation: acoustic and perceptual evidence.

PubMed

Repp, B H; Mann, V A

1982-06-01

Eight native speakers of American English each produced ten tokens of all possible CV, FCV, and VFCV utterances with V = [a] or [u], F = [s] or [integral of], and C = [t] or [k]. Acoustic analysis showed that the formant transition onsets following the stop consonant release were systematically influenced by the preceding fricative, although there were large individual differences. In particular, F3 and F4 tended to be higher following [s] than following [integral of]. The coarticulatory effects were equally large in FCV (e.g.,/sta/) and VFCV (e.g.,/asda/) utterances; that is, they were not reduced when a syllable boundary intervened between fricative and stop. In a parallel perceptual study, the CV portions of these utterances (with release bursts removed to provoke errors) were presented to listeners for identification of the stop consonant. The pattern of place-of-articulation confusions, too, revealed coarticulatory effects due to the excised fricative context.

Antiviral effects of grape seed extract against feline calicivirus, murine norovirus, and hepatitis A virus in model food systems and under gastric conditions.

PubMed

Joshi, Snehal S; Su, Xiaowei; D'Souza, Doris H

2015-12-01

Grape seed extract (GSE) has antiviral activities against hepatitis A virus (HAV) and human norovirus surrogates (feline calicivirus (FCV-F9) and murine norovirus (MNV-1)). The objectives of this study were to determine (1) time and dose-dependence of GSE against FCV-F9, MNV-1, and HAV at room temperature (RT) and 37 °C over 24 h; and (2) GSE effects in model foods (apple juice (AJ) and 2% milk) and simulated gastric conditions at 37 °C. Viruses at ∼5 log PFU/ml were treated with 0.5-8 mg/ml GSE prepared in water, AJ, milk or gastric juices, or water over 24 h at RT or 37 °C. Infectivity of triplicate treatments was evaluated using plaque assays. GSE effects increased with time and concentration. GSE at 1 mg/ml in AJ reduced MNV-1 to undetectable levels after 1 h and by 1 log in milk after 24 h. GSE at 1 and 2 mg/ml in AJ reduced HAV to undetectable levels after 1 h, while 2 and 4 mg/ml GSE in milk caused ∼1 log reduction after 24 h. GSE at 2 mg/ml in intestinal fluid reduced FCV-F9, MNV-1 and HAV to undetectable levels after 6 h. GSE appears to be a suitable natural option for foodborne viral reduction. Copyright © 2015. Published by Elsevier Ltd.

Cold argon-oxygen plasma species oxidize and disintegrate capsid protein of feline calicivirus

PubMed Central

Mor, Sunil K.; Higgins, LeeAnn; Armien, Anibal; Youssef, Mohammed M.; Bruggeman, Peter J.; Goyal, Sagar M.

2018-01-01

Possible mechanisms that lead to inactivation of feline calicivirus (FCV) by cold atmospheric-pressure plasma (CAP) generated in 99% argon-1% O2 admixture were studied. We evaluated the impact of CAP exposure on the FCV viral capsid protein and RNA employing several cultural, molecular, proteomic and morphologic characteristics techniques. In the case of long exposure (2 min) to CAP, the reactive species of CAP strongly oxidized the major domains of the viral capsid protein (VP1) leading to disintegration of a majority of viral capsids. In the case of short exposure (15 s), some of the virus particles retained their capsid structure undamaged but failed to infect the host cells in vitro. In the latter virus particles, CAP exposure led to the oxidation of specific amino acids located in functional peptide residues in the P2 subdomain of the protrusion (P) domain, the dimeric interface region of VP1 dimers, and the movable hinge region linking the S and P domains. These regions of the capsid are known to play an essential role in the attachment and entry of the virus to the host cell. These observations suggest that the oxidative effect of CAP species inactivates the virus by hindering virus attachment and entry into the host cell. Furthermore, we found that the oxidative impact of plasma species led to oxidation and damage of viral RNA once it becomes unpacked due to capsid destruction. The latter effect most likely plays a secondary role in virus inactivation since the intact FCV genome is infectious even after damage to the capsid. PMID:29566061

Comparative Recovery of Two Human Norovirus Surrogates, Feline Calicivirus and Murine Norovirus, with a Wet Vacuum System, Macrofoam-Tipped Swab, and Bottle Extraction Method from Carpets.

PubMed

Buckley, David; Fraser, Angela; Pettigrew, Charles; Anderson, Jeffery; Jiang, Xiuping

2018-05-10

Human noroviruses (HuNoV) are the leading cause of known foodborne illness in the United States, but direct detection during outbreak investigations is challenging. On the other hand, sampling both hard and soft environmental surfaces can be used to improve outbreak investigations. Currently, we lack virus recovery methods for soft surfaces, such as carpet, despite evidence suggesting that carpets contribute to HuNoV outbreaks. Our aim was to compare two recovery methods, wet vacuum and swabbing, for routine carpet sampling of HuNoV against a laboratory reference method known as bottle extraction (BE). Specifically, we compared the microbial vacuum (MVAC), macrofoam-tipped swab (MS), and BE by using HuNoV surrogates, feline calicivirus (FCV) and murine norovirus (MNV), inoculated on wool and nylon carpet carriers. The highest recovery of infectious FCV from wool was 5.51, 3.76, and 5.16 log PFU, whereas on nylon, recovery was 5.03, 3.62, and 4.75 log PFU by using BE, MS, and MVAC, respectively. On the other hand, the highest recovery of infectious MNV from wool was 6.10, 4.50, and 5.99 log PFU, while recovery on nylon was 6.07, 4.58, and 6.13 log PFU by using BE, MS, and MVAC, respectively. Significantly more PFU and genomic copies were recovered by using BE and MVAC compared with MS, while buffer type played a significant role in recovery of infectious FCV.

Advanced chemical hydride-based hydrogen generation/storage system for fuel cell vehicles

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

Breault, R.W.; Rolfe, J.

1998-08-01

Because of the inherent advantages of high efficiency, environmental acceptability, and high modularity, fuel cells are potentially attractive power supplies. Worldwide concerns over clean environments have revitalized research efforts on developing fuel cell vehicles (FCV). As a result of intensive research efforts, most of the subsystem technology for FCV`s are currently well established. These include: high power density PEM fuel cells, control systems, thermal management technology, and secondary power sources for hybrid operation. For mobile applications, however, supply of hydrogen or fuel for fuel cell operation poses a significant logistic problem. To supply high purity hydrogen for FCV operation, Thermomore » Power`s Advanced Technology Group is developing an advanced hydrogen storage technology. In this approach, a metal hydride/organic slurry is used as the hydrogen carrier and storage media. At the point of use, high purity hydrogen will be produced by reacting the metal hydride/organic slurry with water. In addition, Thermo Power has conceived the paths for recovery and regeneration of the spent hydride (practically metal hydroxide). The fluid-like nature of the spent hydride/organic slurry will provide a unique opportunity for pumping, transporting, and storing these materials. The final product of the program will be a user-friendly and relatively high energy storage density hydrogen supply system for fuel cell operation. In addition, the spent hydride can relatively easily be collected at the pumping station and regenerated utilizing renewable sources, such as biomass, natural, or coal, at the central processing plants. Therefore, the entire process will be economically favorable and environmentally friendly.« less

Histologic and Molecular Correlation in Shelter Cats with Acute Upper Respiratory Infection ▿

PubMed Central

Burns, Rachel E.; Wagner, Denae C.; Leutenegger, Christian M.; Pesavento, Patricia A.

2011-01-01

This is a descriptive study designed to correlate diagnostic real-time PCR results with histopathologic lesions in cats with clinical signs of upper respiratory infection (URI). The study occurred over a 9-month period in a single open-intake animal shelter. Cats that were selected for euthanasia by the shelter staff and additionally had URI were included in the study, for a total of 22 study cats. Combined conjunctival and oropharyngeal swab specimens were tested by quantitative real-time PCR (qPCR) for feline herpesvirus type 1 (FHV-1), feline calicivirus (FCV), Mycoplasma felis, Chlamydophila felis, and Bordetella bronchiseptica. Necropsy was performed on all cats, and a complete set of respiratory tract tissues was examined by histopathology. Among 22 cats, 20 were qPCR positive for FHV-1, 7 for M. felis, 5 for FCV, 1 for C. felis, and 0 for B. bronchiseptica. Nine cats were positive for two or more pathogens. Histopathologic lesions were present in all cats, with consistent lesions in the nasal cavity, including acute necroulcerative rhinitis in 16 cats. Histologic or antigenic detection of FHV-1 was seen in 18 of 20 cats positive for FHV-1 by qPCR. No lesions that could be specifically attributed to FCV, M. felis, or C. felis were seen, although interpretation in this cohort could be confounded by coinfection with FHV-1. A significant agreement was found between the amount of FHV-1 DNA determined by qPCR and the presence of specific histopathologic lesions for FHV-1 but not for the other respiratory pathogens. PMID:21562109

Histologic and molecular correlation in shelter cats with acute upper respiratory infection.

PubMed

Burns, Rachel E; Wagner, Denae C; Leutenegger, Christian M; Pesavento, Patricia A

2011-07-01

This is a descriptive study designed to correlate diagnostic real-time PCR results with histopathologic lesions in cats with clinical signs of upper respiratory infection (URI). The study occurred over a 9-month period in a single open-intake animal shelter. Cats that were selected for euthanasia by the shelter staff and additionally had URI were included in the study, for a total of 22 study cats. Combined conjunctival and oropharyngeal swab specimens were tested by quantitative real-time PCR (qPCR) for feline herpesvirus type 1 (FHV-1), feline calicivirus (FCV), Mycoplasma felis, Chlamydophila felis, and Bordetella bronchiseptica. Necropsy was performed on all cats, and a complete set of respiratory tract tissues was examined by histopathology. Among 22 cats, 20 were qPCR positive for FHV-1, 7 for M. felis, 5 for FCV, 1 for C. felis, and 0 for B. bronchiseptica. Nine cats were positive for two or more pathogens. Histopathologic lesions were present in all cats, with consistent lesions in the nasal cavity, including acute necroulcerative rhinitis in 16 cats. Histologic or antigenic detection of FHV-1 was seen in 18 of 20 cats positive for FHV-1 by qPCR. No lesions that could be specifically attributed to FCV, M. felis, or C. felis were seen, although interpretation in this cohort could be confounded by coinfection with FHV-1. A significant agreement was found between the amount of FHV-1 DNA determined by qPCR and the presence of specific histopathologic lesions for FHV-1 but not for the other respiratory pathogens.

The effects of demographic, social, and environmental characteristics on pathogen prevalence in wild felids across a gradient of urbanization

PubMed Central

Logan, Kenneth A.; Alldredge, Mat W.; Carver, Scott; Bevins, Sarah N.; Lappin, Michael; VandeWoude, Sue; Crooks, Kevin R.

2017-01-01

Transmission of pathogens among animals is influenced by demographic, social, and environmental factors. Anthropogenic alteration of landscapes can impact patterns of disease dynamics in wildlife populations, increasing the potential for spillover and spread of emerging infectious diseases in wildlife, human, and domestic animal populations. We evaluated the effects of multiple ecological mechanisms on patterns of pathogen exposure in animal populations. Specifically, we evaluated how ecological factors affected the prevalence of Toxoplasma gondii (Toxoplasma), Bartonella spp. (Bartonella), feline immunodeficiency virus (FIV), and feline calicivirus (FCV) in bobcat and puma populations across wildland-urban interface (WUI), low-density exurban development, and wildland habitat on the Western Slope (WS) and Front Range (FR) of Colorado during 2009–2011. Samples were collected from 37 bobcats and 29 pumas on the WS and FR. As predicted, age appeared to be positively related to the exposure to pathogens that are both environmentally transmitted (Toxoplasma) and directly transmitted between animals (FIV). In addition, WS bobcats appeared more likely to be exposed to Toxoplasma with increasing intraspecific space-use overlap. However, counter to our predictions, exposure to directly-transmitted pathogens (FCV and FIV) was more likely with decreasing space-use overlap (FCV: WS bobcats) and potential intraspecific contacts (FIV: FR pumas). Environmental factors, including urbanization and landscape covariates, were generally unsupported in our models. This study is an approximation of how pathogens can be evaluated in relation to demographic, social, and environmental factors to understand pathogen exposure in wild animal populations. PMID:29121060

PLATINUM AND FUEL CELLS

EPA Science Inventory

Platinum requirements for fuel cell vehicles (FCVS) have been identified as a concern and possible problem with FCV market penetration. Platinum is a necessary component of the electrodes of fuel cell engines that power the vehicles. The platinum is deposited on porous electrodes...

Hemocytes Are Sites of Enteric Virus Persistence within Oysters ▿

PubMed Central

Provost, Keleigh; Dancho, Brooke A.; Ozbay, Gulnihal; Anderson, Robert S.; Richards, Gary P.; Kingsley, David H.

2011-01-01

The goal of this study was to determine how enteric viruses persist within shellfish tissues. Several lines of novel evidence show that phagocytic blood cells (hemocytes) of Eastern oysters (Crassostrea virginica) play an important role in the retention of virus particles. Our results demonstrated an association of virus contamination with hemocytes but not with hemolymph. Live oysters contaminated overnight with hepatitis A virus (HAV) and murine norovirus (MNV) had 56% and 80% of extractable virus associated with hemocytes, respectively. Transfer of HAV-contaminated hemocytes to naïve (virus-free) oysters resulted in naïve oyster meat testing HAV positive for up to 3 weeks. Acid tolerance of HAV, MNV, poliovirus (PV), and feline calicivirus (FCV) correlated with the ability of each virus to persist within oysters. Using reverse transcription-PCR (RT-PCR) to evaluate persistence of these viruses in oysters, we showed that HAV persisted the longest (>21 days) and was most acid resistant, MNV and PV were less tolerant of acidic pH, persisting for up to 12 days and 1 day, respectively, and FCV did not persist (<1 day) within oysters and was not acid tolerant. This suggests that the ability of a virus to tolerate the acidic conditions typical of phagolysosomal vesicles within hemocytes plays a role in determining virus persistence in shellfish. Evaluating oyster and hemocyte homogenates and live contaminated oysters as a prelude to developing improved viral RNA extraction methods, we found that viruses were extracted more expediently from hemocytes than from whole shellfish tissues and gave similar RT-PCR detection sensitivities. PMID:21948840

Critical review of norovirus surrogates in food safety research: rationale for considering volunteer studies.

PubMed

Richards, Gary P

2012-03-01

The inability to propagate human norovirus (NoV) or to clearly differentiate infectious from noninfectious virus particles has led to the use of surrogate viruses, like feline calicivirus (FCV) and murine norovirus-1 (MNV), which are propagatable in cell culture. The use of surrogates is predicated on the assumption that they generally mimic the viruses they represent; however, studies are proving this concept invalid. In direct comparisons between FCV and MNV, their susceptibility to temperatures, environmental and food processing conditions, and disinfectants are dramatically different. Differences have also been noted between the inactivation of NoV and its surrogates, thus questioning the validity of surrogates. Considerable research funding is provided globally each year to conduct surrogate studies on NoVs; however, there is little demonstrated benefit derived from these studies in regard to the development of virus inactivation techniques or food processing strategies. Human challenge studies are needed to determine which processing techniques are effective in reducing NoVs in foods. A major obstacle to clinical trials on NoVs is the perception that such trials are too costly and risky, but in reality, there is far more cost and risk in allowing millions of unsuspecting consumers to contract NoV illness each year, when practical interventions are only a few volunteer studies away. A number of clinical trials have been conducted, providing important insights into NoV inactivation. A shift in research priorities from surrogate research to volunteer studies is essential if we are to identify realistic, practical, and scientifically valid processing approaches to improve food safety.

Inactivation of norovirus surrogates on surfaces and raspberries by steam-ultrasound treatment.

PubMed

Schultz, Anna Charlotte; Uhrbrand, Katrine; Nørrung, Birgit; Dalsgaard, Anders

2012-02-01

Human disease outbreaks caused by norovirus (NoV) following consumption of contaminated raspberries are an increasing problem. An efficient method to decontaminate the fragile raspberries and the equipment used for processing would be an important step in ensuring food safety. A potential surface treatment that combines pressurized steam and high-power ultrasound (steam-ultrasound) was assessed for its efficacy to inactivate human NoV surrogates: coliphage (MS2), feline calicivirus (FCV), and murine norovirus (MNV) inoculated on plastic surfaces and MS2 inoculated on fresh raspberries. The amounts of infectious virus and viral genomes were determined by plaque assay and reverse transcription-real time quantitative PCR (RT-qPCR), respectively. On plastic surfaces, an inactivation of >99.99% was obtained for both MS2 and FCV, corresponding to a 9.1-log and >4.8-log reduction after 1 or 3 s of treatment, respectively; while a 3.7-log (99.9%) reduction of MNV was reached after 3 s of treatment. However, on fresh raspberries only a 1-log reduction (∼89%) of MS2 could be achieved after 1 s of treatment, at which point damage to the texture of the fresh raspberries was evident. Increasing treatment time (0 to 3 s) resulted in negligible reductions of viral genome titers of MS2, FCV, and MNV on plastic surfaces as well as of MS2 inoculated on raspberries. Steam-ultrasound treatment in its current format does not appear to be an appropriate method to achieve sufficient decontamination of NoV-contaminated raspberries. However, steam-ultrasound may be used to decontaminate smooth surface areas and utensils in food production and processing environments.

Feline Calicivirus, Murine Norovirus, Porcine Sapovirus, and Tulane Virus Survival on Postharvest Lettuce.

PubMed

Esseili, Malak A; Saif, Linda J; Farkas, Tibor; Wang, Qiuhong

2015-08-01

Human norovirus (HuNoV) is the leading cause of foodborne illnesses, with an increasing number of outbreaks associated with leafy greens. Because HuNoV cannot be routinely cultured, culturable feline calicivirus (FCV), murine norovirus (MNV), porcine sapovirus (SaV), and Tulane virus (TV) have been used as surrogates. These viruses are generated in different cell lines as infected cell lysates, which may differentially affect their stability. Our objective was to uniformly compare the survival of these viruses on postharvest lettuce while evaluating the effects of cell lysates on their survival. Viruses were semipurified from cell lysates by ultrafiltration or ultracentrifugation followed by resuspension in sterile water. Virus survival was examined before and after semipurification: in suspension at room temperature (RT) until day 28 and on lettuce leaves stored at RT for 3 days or at 4°C for 7 and 14 days. In suspension, both methods significantly enhanced the survival of all viruses. On lettuce, the survival of MNV in cell lysates was similar to that in water, under all storage conditions. In contrast, the survival of FCV, SaV, and TV was differentially enhanced, under different storage conditions, by removing cell lysates. Following semipurification, viruses showed similar persistence to each other on lettuce stored under all conditions, with the exception of ultracentrifugation-purified FCV, which showed a higher inactivation rate than MNV at 4°C for 14 days. In conclusion, the presence of cell lysates in viral suspensions underestimated the survivability of these surrogate viruses, while viral semipurification revealed similar survivabilities on postharvest lettuce leaves. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Clinical efficacy of fidarestat, a novel aldose reductase inhibitor, for diabetic peripheral neuropathy: a 52-week multicenter placebo-controlled double-blind parallel group study.

PubMed

Hotta, N; Toyota, T; Matsuoka, K; Shigeta, Y; Kikkawa, R; Kaneko, T; Takahashi, A; Sugimura, K; Koike, Y; Ishii, J; Sakamoto, N

2001-10-01

The purpose of this study was to evaluate the efficacy of fidarestat, a novel aldose reductase (AR) inhibitor, in a double-blind placebo controlled study in patients with type 1 and type 2 diabetes and associated peripheral neuropathy. A total of 279 patients with diabetic neuropathy were treated with placebo or fidarestat at a daily dose of 1 mg for 52 weeks. The efficacy evaluation was based on change in electrophysiological measurements of median and tibial motor nerve conduction velocity, F-wave minimum latency, F-wave conduction velocity (FCV), and median sensory nerve conduction velocity (forearm and distal), as well as an assessment of subjective symptoms. Over the course of the study, five of the eight electrophysiological measures assessed showed significant improvement from baseline in the fidarestat-treated group, whereas no measure showed significant deterioration. In contrast, in the placebo group, no electrophysiological measure was improved, and one measure significantly deteriorated (i.e., median nerve FCV). At the study conclusion, the fidarestat-treated group was significantly improved compared with the placebo group in two electrophysiological measures (i.e., median nerve FCV and minimal latency). Subjective symptoms (including numbness, spontaneous pain, sensation of rigidity, paresthesia in the sole upon walking, heaviness in the foot, and hypesthesia) benefited from fidarestat treatment, and all were significantly improved in the treated versus placebo group at the study conclusion. At the dose used, fidarestat was well tolerated, with an adverse event profile that did not significantly differ from that seen in the placebo group. The effects of fidarestat-treatment on nerve conduction and the subjective symptoms of diabetic neuropathy provide evidence that this treatment alters the progression of diabetic neuropathy.

Feline panleukopenia virus, feline herpesvirus-1 and feline calicivirus antibody responses in seronegative specific pathogen-free kittens after parenteral administration of an inactivated FVRCP vaccine or a modified live FVRCP vaccine.

PubMed

Lappin, Michael R

2012-02-01

Two groups of feline panleukopenia (FPV), feline calicivirus (FCV) and feline herpesvirus 1 (FHV-1) seronegative kittens (six cats per group) were administered one of two feline viral rhinotracheitis, calcivirus and panleukopenia (FVRCP) vaccines subcutaneously (one inactivated and one modified live) and the serological responses to each agent were followed over 49 days (days 0, 2, 5, 7, 10, 14, 21, 28, 35, 42, 49). While the kittens administered the modified live FPV vaccine were more likely to seroconvert on day 7 after the first inoculation than kittens administered the inactivated vaccine, all kittens had seroconverted by day 14. In contrast, FHV-1 serological responses were more rapid following administration of the inactivated FVRCP vaccine when compared with the modified live FVRCP vaccine. There were no statistical differences between the serological response rates between the two FVRCP vaccines in regard to FCV.

Fuel Cells Advanced Drivetrain

DTIC Science & Technology

2010-08-09

T800 Silverado Military specific system upscale (4WD) HydroGen3 – CH2 HydroGen3 – LH2 4010 – Early Adopter Engineering Model (GEN Nadeau) Gen4...Timeline Maintenance Infrastructure Fort Belvoir, VA 2003-ongoing Full FCV and Volt Maintenance 350,700bar LH2 (Decommissioned) Volt Charging(pending

Controlled Hydrogen Fleet and Infrastructure Demonstration Project

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

Dr. Scott Staley

2010-03-31

This program was undertaken in response to the US Department of Energy Solicitation DE-PS30-03GO93010, resulting in this Cooperative Agreement with the Ford Motor Company and BP to demonstrate and evaluate hydrogen fuel cell vehicles and required fueling infrastructure. Ford initially placed 18 hydrogen fuel cell vehicles (FCV) in three geographic regions of the US (Sacramento, CA; Orlando, FL; and southeast Michigan). Subsequently, 8 advanced technology vehicles were developed and evaluated by the Ford engineering team in Michigan. BP is Ford's principal partner and co-applicant on this project and provided the hydrogen infrastructure to support the fuel cell vehicles. BP ultimatelymore » provided three new fueling stations. The Ford-BP program consists of two overlapping phases. The deliverables of this project, combined with those of other industry consortia, are to be used to provide critical input to hydrogen economy commercialization decisions by 2015. The program's goal is to support industry efforts of the US President's Hydrogen Fuel Initiative in developing a path to a hydrogen economy. This program was designed to seek complete systems solutions to address hydrogen infrastructure and vehicle development, and possible synergies between hydrogen fuel electricity generation and transportation applications. This project, in support of that national goal, was designed to gain real world experience with Hydrogen powered Fuel Cell Vehicles (H2FCV) 'on the road' used in everyday activities, and further, to begin the development of the required supporting H2 infrastructure. Implementation of a new hydrogen vehicle technology is, as expected, complex because of the need for parallel introduction of a viable, available fuel delivery system and sufficient numbers of vehicles to buy fuel to justify expansion of the fueling infrastructure. Viability of the fuel structure means widespread, affordable hydrogen which can return a reasonable profit to the fuel provider, while viability of the vehicle requires an expected level of cost, comfort, safety and operation, especially driving range, that consumers require. This presents a classic 'chicken and egg' problem, which Ford believes can be solved with thoughtful implementation plans. The eighteen Ford Focus FCV vehicles that were operated for this demonstration project provided the desired real world experience. Some things worked better than expected. Most notable was the robustness and life of the fuel cell. This is thought to be the result of the full hybrid configuration of the drive system where the battery helps to overcome the performance reduction associated with time related fuel cell degradation. In addition, customer satisfaction surveys indicated that people like the cars and the concept and operated them with little hesitation. Although the demonstrated range of the cars was near 200 miles, operators felt constrained because of the lack of a number of conveniently located fueling stations. Overcoming this major concern requires overcoming a key roadblock, fuel storage, in a manner that permits sufficient quantity of fuel without sacrificing passenger or cargo capability. Fueling infrastructure, on the other hand, has been problematic. Only three of a planned seven stations were opened. The difficulty in obtaining public approval and local government support for hydrogen fuel, based largely on the fear of hydrogen that grew from past disasters and atomic weaponry, has inhibited progress and presents a major roadblock to implementation. In addition the cost of hydrogen production, in any of the methodologies used in this program, does not show a rapid reduction to commercially viable rates. On the positive side of this issue was the demonstrated safety of the fueling station, equipment and process. In the Ford program, there were no reported safety incidents.« less

AN INTEGRATED ASSESSMENT OF THE IMPACTS OF HYDROGEN ECONOMY ON TRANSPORTATION, ENERGY USE, AND AIR EMISSIONS

EPA Science Inventory

This paper presents an analysis of the potential energy, economic and environmental implications of hydrogen fuel cell vehicle (H2-FCV) penetration into the U.S. light duty vehicle fleet. The approach, which uses the U.S. EPA MARKet ALlocation technology database and model, allow...

Inactivation of HAV and norovirus surrogates within raw shellfish and other foods

USDA-ARS?s Scientific Manuscript database

High pressure processing can inactivate hepatitis A virus, (HAV) and the human norovirus surrogates, feline calicivirus (FCV) and murine norovirus (MNV), in foods such as oysters, strawberries, and green onions. A 5-min 400-Megapascals (MPa) treatment at 5 degrees C and a 1–min 400-MPa treatment at ...

Inactivation of Tulane virus, a novel surrogate for human norovirus

USDA-ARS?s Scientific Manuscript database

Human noroviruses (HuNoVs) are the major cause of non-bacterial epidemics of gastroenteritis. Due to the inability to cultivate HuNoVs and the lack of an efficient small animal model, surrogates are used to study HuNoV biology. Two such surrogates, the feline calicivirus (FCV) and the murine norovir...

Critical review of norovirus surrogates in food safety research: rationale for considering volunteer studies

USDA-ARS?s Scientific Manuscript database

The inability to propagate human norovirus (NoV) or to clearly differentiate infectious from noninfectious virus particles have led to the use of surrogate viruses, like feline calicivirus (FCV) and murine norovirus-1 (MNV), which are propagatable in cell culture. The use of surrogates is predicate...

Virucidal effects of bleach activators, sodium alkyl acyloxybenzene sulfonate and acyloxybenzoic acid, against Feline calicivirus.

PubMed

Tobe, Seiichi; Hoshi, Marika; Iizuka, Kinue; Tadenuma, Hirohiko; Takaoka, Hiromitsu; Komoriya, Tomoe; Kohno, Hideki

2012-01-01

Noroviruses (NVs) are major causative pathogens of gastroenteritis. The disinfection of contaminated clothing during common household washing is desirable. The virucidal effects of 2 bleach activators, sodium alkyl acyloxybenzene sulfonate (OBS) and alkyl acyloxybenzoic acid (OBC), were studied using Feline calicivirus (FCV) as a surrogate for NVs. FCV was added to solutions containing either OBS or OBC and sodium percarbonate at various temperatures and for varying lengths of time. OBS and OBC, which generate long carbon chain peroxy acids, enhanced the virucidal effect of sodium percarbonate (PC). In particular, sodium lauroyloxybenzene sulfonate (OBS-12) and decanoyloxybenzoic acid (OBC-10) showed superior virucidal effects. Although the virucidal effect of 38-200 mg/L OBS-12 was maintained with 2-5% (v/v) horse serum, there was less of an effect with the same concentration of available chlorine. OBS and OBC have been used as ingredients in some laundry products to increase bleaching activity. It is expected that the use of OBS and OBC is also effective for the inactivation of NVs under common household washing conditions.

Blunted cyclic variation of heart rate predicts mortality risk in post-myocardial infarction, end-stage renal disease, and chronic heart failure patients

PubMed Central

Hayano, Junichiro; Yasuma, Fumihiko; Watanabe, Eiichi; Carney, Robert M.; Stein, Phyllis K.; Blumenthal, James A.; Arsenos, Petros; Gatzoulis, Konstantinos A.; Takahashi, Hiroshi; Ishii, Hideki; Kiyono, Ken; Yamamoto, Yoshiharu; Yoshida, Yutaka; Yuda, Emi; Kodama, Itsuo

2017-01-01

Abstract Aims Cyclic variation of heart rate (CVHR) associated with sleep-disordered breathing is thought to reflect cardiac autonomic responses to apnoeic/hypoxic stress. We examined whether blunted CVHR observed in ambulatory ECG could predict the mortality risk. Methods and results CVHR in night-time Holter ECG was detected by an automated algorithm, and the prognostic relationships of the frequency (FCV) and amplitude (ACV) of CVHR were examined in 717 patients after myocardial infarction (post-MI 1, 6% mortality, median follow-up 25 months). The predictive power was prospectively validated in three independent cohorts: a second group of 220 post-MI patients (post-MI 2, 25.5% mortality, follow-up 45 months); 299 patients with end-stage renal disease on chronic haemodialysis (ESRD, 28.1% mortality, follow-up 85 months); and 100 patients with chronic heart failure (CHF, 35% mortality, follow-up 38 months). Although CVHR was observed in ≥96% of the patients in all cohorts, FCV did not predict mortality in any cohort. In contrast, decreased ACV was a powerful predictor of mortality in the post-MI 1 cohort (hazard ratio [95% CI] per 1 ln [ms] decrement, 2.9 [2.2–3.7], P < 0.001). This prognostic relationship was validated in the post-MI 2 (1.8 [1.4–2.2], P < 0.001), ESRD (1.5 [1.3–1.8], P < 0.001), and CHF (1.4 [1.1–1.8], P = 0.02) cohorts. The prognostic value of ACV was independent of age, gender, diabetes, β-blocker therapy, left ventricular ejection fraction, sleep-time mean R-R interval, and FCV. Conclusion Blunted CVHR detected by decreased ACV in a night-time Holter ECG predicts increased mortality risk in post-MI, ESRD, and CHF patients. PMID:27789562

Blunted cyclic variation of heart rate predicts mortality risk in post-myocardial infarction, end-stage renal disease, and chronic heart failure patients.

PubMed

Hayano, Junichiro; Yasuma, Fumihiko; Watanabe, Eiichi; Carney, Robert M; Stein, Phyllis K; Blumenthal, James A; Arsenos, Petros; Gatzoulis, Konstantinos A; Takahashi, Hiroshi; Ishii, Hideki; Kiyono, Ken; Yamamoto, Yoshiharu; Yoshida, Yutaka; Yuda, Emi; Kodama, Itsuo

2017-08-01

Cyclic variation of heart rate (CVHR) associated with sleep-disordered breathing is thought to reflect cardiac autonomic responses to apnoeic/hypoxic stress. We examined whether blunted CVHR observed in ambulatory ECG could predict the mortality risk. CVHR in night-time Holter ECG was detected by an automated algorithm, and the prognostic relationships of the frequency (FCV) and amplitude (ACV) of CVHR were examined in 717 patients after myocardial infarction (post-MI 1, 6% mortality, median follow-up 25 months). The predictive power was prospectively validated in three independent cohorts: a second group of 220 post-MI patients (post-MI 2, 25.5% mortality, follow-up 45 months); 299 patients with end-stage renal disease on chronic haemodialysis (ESRD, 28.1% mortality, follow-up 85 months); and 100 patients with chronic heart failure (CHF, 35% mortality, follow-up 38 months). Although CVHR was observed in ≥96% of the patients in all cohorts, FCV did not predict mortality in any cohort. In contrast, decreased ACV was a powerful predictor of mortality in the post-MI 1 cohort (hazard ratio [95% CI] per 1 ln [ms] decrement, 2.9 [2.2-3.7], P < 0.001). This prognostic relationship was validated in the post-MI 2 (1.8 [1.4-2.2], P < 0.001), ESRD (1.5 [1.3-1.8], P < 0.001), and CHF (1.4 [1.1-1.8], P = 0.02) cohorts. The prognostic value of ACV was independent of age, gender, diabetes, β-blocker therapy, left ventricular ejection fraction, sleep-time mean R-R interval, and FCV. Blunted CVHR detected by decreased ACV in a night-time Holter ECG predicts increased mortality risk in post-MI, ESRD, and CHF patients. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Cardiology.

In vitro influence of D/L-lactic acid, sodium chloride and sodium nitrite on the infectivity of feline calicivirus and of ECHO virus as potential surrogates for foodborne viruses.

PubMed

Straube, J; Albert, T; Manteufel, J; Heinze, J; Fehlhaber, K; Truyen, U

2011-11-15

The importance of foodborne viruses is increasingly recognized. Thus, the effect of commonly used food preservation methods on the infectivity of viruses is questioned. In this context, we investigated the antiviral properties of D,L-lactic acid, sodium chloride and sodium nitrite by in vitro studies. Two model viruses, Feline Calicivirus (FCV) and Enteric Cytophatic Human Orphan (ECHO) virus, were chosen for this study simulating important foodborne viruses (human noroviruses (NoV) and human enteroviruses, resp.). The model viruses were exposed to different solutions of D,L-lactic acid (0.1-0.4% w/w, pH 6.0-3.2), of sodium chloride (2-20%, w/v) and of sodium nitrite (100, 150 and 200 ppm) at 4 and 20 °C for a maximum of 7 days. Different results were obtained for the two viruses. ECHO virus was highly stable against D,L-lactic acid and sodium chloride when tested under all conditions. On the contrary, FCV showed less stability but was not effectively inactivated when exposed to low acid and high salt conditions at refrigeration temperatures (4 °C). FCV titers decreased more markedly at 20 °C than 4 °C in all experiments. Sodium nitrite did not show any effect on the inactivation of both viruses. The results indicate that acidification, salting or curing maybe insufficient for effective inactivation of foodborne viruses such as NoV or human enteroviruses during food processing. Thus, application of higher temperature during fermentation and ripening processes maybe more effective toward the inactivation kinetics of less stable viruses. Nevertheless, more studies are needed to examine the antiviral properties of these preserving agents on virus survival and inactivation kinetics in the complex food matrix. Copyright © 2011 Elsevier B.V. All rights reserved.

Survival of human norovirus surrogates in milk, orange, and pomegranate juice, and juice blends at refrigeration (4 °C).

PubMed

Horm, Katie Marie; D'Souza, Doris Helen

2011-08-01

Fresh fruits, juices, and beverages have been implicated in human noroviral and hepatitis A virus outbreaks. The purpose of this study was to determine the survival of human norovirus surrogates (murine norovirus, MNV-1; feline calicivirus, FCV-F9; and bacteriophage MS2) in juices (orange and pomegranate juices), juice blends (pomegranate and orange juice) and milk over 0, 1, 2, 7, 14, and 21 days at refrigeration (4 °C). Juices, juice blends, and milk were inoculated with each virus over 21 days, serially diluted in cell culture media, and plaque assayed. MNV-1 showed no reduction in titer after 21 days in orange juice and milk, but moderate reduction (1.4 log) in pomegranate juice from a titer of 5 log(10) PFU/ml. However, MNV-1 was completely reduced after 7 days in the orange and pomegranate juice blend. FCV-F9 from a titer of 6 log(10) PFU/ml was completely reduced after 14 days in orange as well as pomegranate juice and by ∼ 3 logs after 21 days in milk at 4 °C. Interestingly, FCV-F9 was completely reduced after 1 day in the orange and pomegranate juice blend at 4 °C. MS2 was reduced by ∼ 1.28 log after 21 days in orange juice from a titer of 6 log(10) PFU/ml, and <1 log after 21 days in milk or pomegranate juice, with juice blends showing minimal reduction (<1 log) after 21 days at 4 °C. These results show the survival pattern of noroviruses that aid in the transmission of foodborne viral outbreaks. The data obtained can be used in quantitative viral risk assessment studies and to develop improved measures to prevent virus survival towards controlling outbreaks. Copyright © 2011. Published by Elsevier Ltd.

Common virus infections in cats, before and after being placed in shelters, with emphasis on feline enteric coronavirus.

PubMed

Pedersen, N C; Sato, R; Foley, J E; Poland, A M

2004-04-01

The purpose of this study was to determine the origin and subsequent spread of feline calicivirus (FCV), feline herpesvirus (FHV), and feline enteric coronavirus (FECV) in cats relinquished to shelters. FCV was isolated from the oral fauces of 11% of healthy cats upon entry, and isolation rates were highest for kittens (33%). FHV shedding was very low (4%) at the time of entry and occurred mainly in juveniles. FECV shedding was also common among newly relinquished cats (33%), especially older kittens and juveniles (90%). The subsequent spread of all three viruses was rapid and efficient in the shelter environment. Fifteen percent of cats were shedding FCV, 52% FHV, and 60% FECV after 1 week. More detailed studies were done with FECV shedding, which could be accurately quantitated. The amounts of FECV shed by infected cats ranged from 10(2)to 10(16)particles/swab of feces. FECV shedding was several logs higher in young kittens with primary infection than adult cats with primary infections. The mean levels of FECV shedding among adults were the same for primary and chronic infections. Although shelters were not the primary source of these viruses for many relinquished cats, factors intrinsic to the shelter environment were critical in amplifying shedding and spread to susceptible individuals. Extrinsic factors were especially important for the spread of FHV and FECV. FHV shedding rates increased from 4% to 50% in 1 week's time. The speed and magnitude of the increase in FHV shedding suggested that there was reactivation of latent infections as well as acquisition of new infections. FECV shedding increased 10 to 1,000,000 fold in 1 week among cats that were already infected at entry, and more than one-half of initially negative cats were shedding FECV a week later. Feline calicivirus infection was the least likely to spread in the shelter. The infection rate only increased from 11 to 15% in 1 week.

Antibodies to canine and feline viruses in spotted hyenas (Crocuta crocuta) in the Masai Mara National Reserve.

PubMed

Harrison, Tara M; Mazet, Jonna K; Holekamp, Kay E; Dubovi, Edward; Engh, Anne L; Nelson, Keith; Van Horn, Russell C; Munson, Linda

2004-01-01

Spotted hyenas (Crocuta crocuta) are abundant predators in the Serengeti ecosystem and interact with other species of wild carnivores and domestic animals in ways that could encourage disease transmission. Hyenas also have a unique hierarchical social system that might affect the flow of pathogens. Antibodies to canine distemper virus (CDV), feline immunodeficiency virus (FIV), feline panleukopenia virus/canine parvovirus (FPLV/CPV), feline coronavirus/ feline infectious peritonitis virus (FECV/IPV), feline calicivirus (FCV), and feline herpesvirus 1 (FHV1) have been detected in other Serengeti predators, indicating that these viruses are present in the ecosystem. The purpose of this study was to determine whether spotted hyenas also had been infected with these viruses and to assess risk factors for infection. Serum samples were collected between 1993 and 2001 from 119 animals in a single clan for which behavioral data on social structure were available and from 121 hyenas ill several other clans. All animals resided in the Masai Mara National Reserve. Antibodies to CDV, FIV, FPLV/CPV, FECV/FIPV, FCV, and FHV1 were present in 47%, 3.5%, 81%, 36%, 72%, and 0.5% of study hyenas, respectively. Antibody prevalence was greater in adults for FIV and FECV/FIPV, and being a female of high social rank was a risk factor for FIV. Hyenas near human habitation appeared to be at lower risk to have CDV, FIV, and FECV/FIPV antibodies, whereas being near human habitation increased the risk for FPLV/CPV antibodies. Canine (distemper virus and FECV/FIPV antibody prevalence varied considerably over time, whereas FIV, FPLV/CPV, and FCV had a stable, apparently endemic temporal pattern. These results indicate that hyenas might play a role in the ecology of these viruses in the Serengeti ecosystem. The effect of these viruses on hyena health should be further investigated. The lower prevalence of CDV antibody-positive hyenas near human habitation suggests that reservoirs for CDV other than domestic dogs are present in the Serengeti ecosystem.

Pulmonary function and dysfunction in multiple sclerosis.

PubMed

Smeltzer, S C; Utell, M J; Rudick, R A; Herndon, R M

1988-11-01

Pulmonary function was studied in 25 patients with clinically definite multiple sclerosis with a range of motor impairment. Forced vital capacity (FVC), maximal voluntary ventilation (MVV), and maximal expiratory pressure (MEP) were normal in the ambulatory patients (mean greater than or equal to 80% predicted) but reduced in bedridden patients (mean, 38.5%, 31.6%, and 36.3% predicted; FCV, MVV, and MEP, respectively) and wheelchair-bound patients with upper extremity involvement (mean, 69.4%, 50.4%, and 62.6% predicted; FVC, MVV, and MEP, respectively). Forced vital capacity, MVV, and MEP correlated with Kurtzke Expanded Disability Status scores (tau = -0.72, -0.70, and -0.65) and expiratory muscle weakness occurred most frequently. These findings demonstrate that marked expiratory weakness develops in severely paraparetic patients with multiple sclerosis and the weakness increases as the upper extremities become increasingly involved.

Antiviral effects of black raspberry (Rubus coreanus) seed extract and its polyphenolic compounds on norovirus surrogates.

PubMed

Lee, Ji-Hye; Bae, Sun Young; Oh, Mi; Seok, Jong Hyeon; Kim, Sella; Chung, Yeon Bin; Gowda K, Giri; Mun, Ji Young; Chung, Mi Sook; Kim, Kyung Hyun

2016-06-01

Black raspberry seeds, a byproduct of wine and juice production, contain large quantities of polyphenolic compounds. The antiviral effects of black raspberry seed extract (RCS) and its fraction with molecular weight less than 1 kDa (RCS-F1) were examined against food-borne viral surrogates, murine norovirus-1 (MNV-1) and feline calicivirus-F9 (FCV-F9). The maximal antiviral effect was achieved when RCS or RCS-F1 was added simultaneously to cells with MNV-1 or FCV-F9, reaching complete inhibition at 0.1-1 mg/mL. Transmission electron microscopy (TEM) images showed enlarged viral capsids or disruption (from 35 nm to up to 100 nm) by RCS-F1. Our results thus suggest that RCS-F1 can interfere with the attachment of viral surface protein to host cells. Further, two polyphenolic compounds derived from RCS-F1, cyanidin-3-glucoside (C3G) and gallic acid, identified by liquid chromatography-tandem mass spectrometry, showed inhibitory effects against the viruses. C3G was suggested to bind to MNV-1 RNA polymerase and to enlarge viral capsids using differential scanning fluorimetry and TEM, respectively.

Survival of viral pathogens in animal feed ingredients under transboundary shipping models

PubMed Central

Bauermann, Fernando V.; Niederwerder, Megan C.; Singrey, Aaron; Clement, Travis; de Lima, Marcelo; Long, Craig; Patterson, Gilbert; Sheahan, Maureen A.; Stoian, Ana M. M.; Petrovan, Vlad; Jones, Cassandra K.; De Jong, Jon; Ji, Ju; Spronk, Gordon D.; Minion, Luke; Christopher-Hennings, Jane; Zimmerman, Jeff J.; Rowland, Raymond R. R.; Nelson, Eric; Sundberg, Paul; Diel, Diego G.

2018-01-01

The goal of this study was to evaluate survival of important viral pathogens of livestock in animal feed ingredients imported daily into the United States under simulated transboundary conditions. Eleven viruses were selected based on global significance and impact to the livestock industry, including Foot and Mouth Disease Virus (FMDV), Classical Swine Fever Virus (CSFV), African Swine Fever Virus (ASFV), Influenza A Virus of Swine (IAV-S), Pseudorabies virus (PRV), Nipah Virus (NiV), Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), Swine Vesicular Disease Virus (SVDV), Vesicular Stomatitis Virus (VSV), Porcine Circovirus Type 2 (PCV2) and Vesicular Exanthema of Swine Virus (VESV). Surrogate viruses with similar genetic and physical properties were used for 6 viruses. Surrogates belonged to the same virus families as target pathogens, and included Senecavirus A (SVA) for FMDV, Bovine Viral Diarrhea Virus (BVDV) for CSFV, Bovine Herpesvirus Type 1 (BHV-1) for PRV, Canine Distemper Virus (CDV) for NiV, Porcine Sapelovirus (PSV) for SVDV and Feline Calicivirus (FCV) for VESV. For the remaining target viruses, actual pathogens were used. Virus survival was evaluated using Trans-Pacific or Trans-Atlantic transboundary models involving representative feed ingredients, transport times and environmental conditions, with samples tested by PCR, VI and/or swine bioassay. SVA (representing FMDV), FCV (representing VESV), BHV-1 (representing PRV), PRRSV, PSV (representing SVDV), ASFV and PCV2 maintained infectivity during transport, while BVDV (representing CSFV), VSV, CDV (representing NiV) and IAV-S did not. Notably, more viruses survived in conventional soybean meal, lysine hydrochloride, choline chloride, vitamin D and pork sausage casings. These results support published data on transboundary risk of PEDV in feed, demonstrate survival of certain viruses in specific feed ingredients (“high-risk combinations”) under conditions simulating transport between continents and provide further evidence that contaminated feed ingredients may represent a risk for transport of pathogens at domestic and global levels. PMID:29558524

Pattern recognition for Space Applications Center director's discretionary fund

NASA Technical Reports Server (NTRS)

Singley, M. E.

1984-01-01

Results and conclusions are presented on the application of recent developments in pattern recognition to spacecraft star mapping systems. Sensor data for two representative starfields are processed by an adaptive shape-seeking version of the Fc-V algorithm with good results. Cluster validity measures are evaluated, but not found especially useful to this application. Recommendations are given two system configurations worthy of additional study,

Comparative efficacy of Zataria multiflora Boiss., Origanum compactum and Eugenia caryophyllus essential oils against E. coli O157:H7, feline calicivirus and endogenous microbiota in commercial baby-leaf salads.

PubMed

Azizkhani, Maryam; Elizaquível, Patricia; Sánchez, Gloria; Selma, María Victoria; Aznar, Rosa

2013-09-02

Ready-to-eat salads using baby-leaf and multi-leaf mixes are one of the most promising developments in the fresh-cut food industry. There is great interest in developing novel decontamination treatments, which are both safe for consumers and more efficient against foodborne pathogens. In this study, emulsions of essential oils (EOs) from Origanum compactum (oregano), Eugenia caryophyllus (clove), and Zataria multiflora Boiss (zataria) were applied by spray (0.8 ml) after the sanitizing washing step. The aim was to investigate their ability to control the growth of potentially cross-contaminating pathogens and endogenous microbiota in commercial baby leaves, processed in a fresh-cut produce company. Zataria EO emulsions of 3%, 5% and 10% reduced Escherichia coli O157:H7 by 1.7, 2.2 and 3.5 log cfu/g in baby-leaf salads after 5 days of storage at 7°C. By contrast, reductions in E. coli O157:H7 counts remained the same when clove was applied at concentrations of 5% and 10% (2.5 log cfu/g reduction). Oregano (10%) reduced inoculated E. coli O157:H7 counts in baby-leaf salads by a maximum of 0.5 log cfu/g after 5 days of storage. Zataria showed strong antimicrobial efficacy against E. coli O157:H7 and also against the endogenous microbiota of baby-leaf salads stored for 9 days. Feline calicivirus (FCV), a norovirus surrogate, survived on inoculated baby-leaf salads during refrigerated storage (9 days at 7°C) regardless of treatment. Refrigeration temperatures completely annulled the effectiveness of the EOs against FCV inoculated in baby-leaf salads as occurred in FCV cultures. This study shows that EOs, and zataria in particular, have great potential use as an additional barrier to reduce contamination-related risks in baby-leaf salads. However, further research should be done into foodborne viruses in order to improve food safety. © 2013.

The use of flow cytometry to accurately ascertain total and viable counts of Lactobacillus rhamnosus in chocolate.

PubMed

Raymond, Yves; Champagne, Claude P

2015-04-01

The goals of this study were to evaluate the precision and accuracy of flow cytometry (FC) methodologies in the evaluation of populations of probiotic bacteria (Lactobacillus rhamnosus R0011) in two commercial dried forms, and ascertain the challenges in enumerating them in a chocolate matrix. FC analyses of total (FC(T)) and viable (FC(V)) counts in liquid or dried cultures were almost two times more precise (reproducible) than traditional direct microscopic counts (DCM) or colony forming units (CFU). With FC, it was possible to ascertain low levels of dead cells (FC(D)) in fresh cultures, which is not possible with traditional CFU and DMC methodologies. There was no interference of chocolate solids on FC counts of probiotics when inoculation was above 10(7) bacteria per g. Addition of probiotics in chocolate at 40 °C resulted in a 37% loss in viable cells. Blending of the probiotic powder into chocolate was not uniform which raised a concern that the precision of viable counts could suffer. FCT data can serve to identify the correct inoculation level of a sample, and viable counts (FCV or CFU) can subsequently be better interpreted. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

Two-Dimensional Microdischarge Jet Array in Air: Characterization and Inactivation of Virus

NASA Astrophysics Data System (ADS)

Nayak, Gaurav

Cold atmospheric pressure plasmas (CAPs) have proven to be quite effective for surface disinfection, wound healing and even cancer treatment in recent years. One of the major societal challenges faced today is related to illness caused by food-borne bacteria and viruses, particularly in minimally processed, fresh or ready-to-eat foods. Gastroenteritis outbreaks, caused, for example, by the human Norovirus (NV) is a growing concern. Current used technologies seem not to be fully effective. In this work we focus on a possible solution based on CAP technology for surface disinfection. Many discharge sources have been studied for disinfection and the two major challenges faced are the use of expensive noble gases (Ar/He) by many plasma sources and the difficulty to scale up the plasma devices. The efficacies of these devices also vary for different plasma sources, making it difficult to compare results from different research groups. Also, the interaction of plasma with the biological matter is not understood well, particularly for virus. In this work, a two-dimensional array of micro dielectric barrier discharge is used to treat Feline Calicivirus (FCV), which is a surrogate for human Norovirus. The plasma source can be operated with an air flow rate (up to 94 standard liters per minute or slm). The use of such discharge source also raises important scientific questions which are addressed in this work. These questions include the effect of gas flow rate on discharge properties and the production of reactive species responsible for virus inactivation and the underlying inactivation mechanism. The plasma source is characterized via several diagnostic techniques such as current voltage measurements for electrical characterization and power measurements, optical emission spectroscopy (OES) to determine the gas temperature, cross-correlation spectroscopy (CCS) for microdischarge evolution and timescales, UV absorption spectroscopy to measure the O3 density, absolute IR OES to measure the O2(a 1Deltag) density and spectrophotometry to estimate the NOx species density in aqueous medium. The results show that the discharge activity is strongly dependent on the gas flow rate particularly for gas residence times comparable to the applied high voltage cycle. The maximum difference in gas temperature at extreme plasma conditions do not exceed 50 K. The NO density is found to be reducing with smaller gas residence time. It is found that the reduced field E/N is dependent on the flow rate. The observed variation in the electric field is attributed to the change in the neutral gas densities. Both gas residence time and humidity have an impact on the space-charge distribution. The O 3 density is found to increase with increasing power density and saturates at higher power above 12 W, and the maximum density of 1022 m-3 is achieved at an intermediate flow rate of 20 slm. An optimal condition for O2(a 1Deltag) generation is found that is a balance between power and gas residence. Higher specific energy leads to higher increase of O2(a 1Deltag) density as compared to the O3 density. It is also observed that the O2(a 1Deltag) to O3 density ratio could be controlled by the flow rate from 0.7 to almost 0. The discharge source is used for FCV inactivation on surfaces (in the gas phase) and suspended in solution. Discharge power and treatment time have strong effect on the reduction in virus titer, while exposure distance or flow rate have negligible effect. Humidity plays a major effect on FCV inactivation on surfaces, leading to complete inactivation (>4 log10) within 3 minutes of treatment. FCV inactivation can be explained by O3 in gas phase and RNS in liquid phase. Nonetheless synergistic effects of ROS and RNS cannot be excluded, as similar production rates of O3 and NOx in discharge are determined. The O2(a 1Deltag) density at conditions used for FCV treatment is at least 2 orders of magnitude lower than the ozone density and is not a dominant factor in the inactivation.

Deriving sediment Interstitial Water Remediation Goals ...

EPA Pesticide Factsheets

Background/Objectives. Passive sampling is becoming a frequently used measurement technique at Superfund sites with contaminated sediments. Passive sampling measures the concentrations of freely dissolved chemicals (Cfrees) in the sediment interstitial water. The freely dissolved chemical is a good surrogate for and a very practical means for estimating the concentrations of bioavailable chemical in the sediments. Building from this approach, a methodology is proposed to derive sediment Interstitial Water Remediation Goals (IWRGs) for the protection of benthic organisms from direct toxicity using Cfrees measured with passive sampling.Approach/Activities. In the early 2000s, EPA developed and released Equilibrium Partitioning Sediment Benchmarks (ESBs) for a series of chemicals. ESBs are intended to be chemical concentrations below which unacceptable toxicity to benthic organisms does not occur. The ESBs (expressed with the units of ug/g OC) were derived using the equations:ESB= K_OC×FCV where K_OC=0.00028+0.983K_OWThe KOC is the organic carbon normalized sediment-water chemical partition coefficient, FCV is the Final Chronic Value from EPA’s ambient water quality criteria for the protection of aquatic life, and KOW is the n-octanol/water partition coefficient for the chemical. At a specific site, the remedial goal (CS:ESB µg/kg-dw) in sediment are then derived using the site-specific fraction of organic carbon in the sediment (fOC:SS) at the site:C_

An efficient recovery method for enteric viral particles from agricultural soils.

PubMed

Brassard, Julie; Gagné, Marie-Josée

2018-06-24

Enteric viruses have been recognized as the leading cause of non-bacterial gastroenteritis and hepatitis outbreaks around the world. Understanding their prevalence and persistence in the environment is important for the effective control of these infections. The aim of this study was to develop an efficient recovery procedure for viral infectious particles from agricultural soils. Samples (25 g) of soil (black earth soil, loamy soil, and sandy soil) were spiked with murine norovirus (MNV) and feline calicivirus (FCV), mixed with five different buffers and viral genetic material was extracted by 3 commercial kits. The combination consisted by the modified Eagle's medium buffer followed by Dynabeads nucleic acid extraction kit, when the detection is conducted by molecular biology, has been identified as being the most effective procedure to preserve the viral particle infectivity and also to remove PCR inhibitors.The recovery percentages of infectious MNV for the 3 types of soils were 54.3%, 54.4%, and 56.9%. In contrast, the titres of the FCV varied depending on the type of soil, and the recovery percentages were 47.8% in the black soil, 15.6% in the loamy soil, and 17.7% in the sandy soil. Also, the results presented in this study highlight the importance of using an internal process control such as artificial inoculation with MNV at known concentrations during detection by molecular methods, in order to avoid the occurrence of false negative reactions. Copyright © 2018. Published by Elsevier B.V.

Exposure to selected Pathogens in to selected pathogens in Geoffroy's cats and domestic carnivores from central Argentina.

PubMed

Uhart, Marcela M; Rago, M Virginia; Marull, Carolina A; Ferreyra, Hebe del Valle; Pereira, Javier A

2012-10-01

Wild carnivores share a high percentage of parasites and viruses with closely related domestic carnivores. Because of increased overlap and potential contact with domestic species, we conducted a retrospective serosurvey for 11 common carnivore pathogens in 40 Geoffroy's cats (Leopardus geoffroyi) sampled between 2000 and 2008 within or near two protected areas in central Argentina (Lihué Calel National Park, La Pampa, and Campos del Tuyú National Park, Buenos Aires), as well as five domestic cats and 11 domestic dogs from catde ranches adjacent to Lihué Calel Park. Geoffroy's cats had detectable antibody to canine distemper virus (CDV), feline calicivirus (FCV), feline coronavirus, feline panleukopenia virus (FPV), Toxoplasma gondii, Leptospira interrogans (serovars Ictero/Icter and Ballum), and Dirofilaria immitis. None of the wild cats had antibodies to feline herpesvirus, feline immunodeficiency virus (FIV), feline leukemia virus, or rabies virus. Domestic dogs had antibodies to CDV, canine adenovirus, canine herpesvirus, and canine parvovirus. Antibodies to FPV, FCV, FIV, and T. gondii were found in domestic cats. We provide the first data on exposure of free-ranging Geoffroy's cats to pathogens at two sites within the core area of the species distribution range, including the first report of antibodies to CDV in this species. We encourage continued monitoring for diseases in wild and domestic carnivores as well as preventive health care for domestic animals, particularly in park buffer zones where overlap is greatest.

Deriving Freshwater Quality Criteria for Iron, Lead, Nickel, and Zinc for Protection of Aquatic Life in Malaysia

PubMed Central

Shuhaimi-Othman, M.; Nadzifah, Y.; Nur-Amalina, R.; Umirah, N. S.

2012-01-01

Freshwater quality criteria for iron (Fe), lead (Pb), nickel (Ni), and zinc (Zn) were developed with particular reference to aquatic biota in Malaysia, and based on USEPA's guidelines. Acute toxicity tests were performed on eight different freshwater domestic species in Malaysia which were Macrobrachium lanchesteri (prawn), two fish: Poecilia reticulata and Rasbora sumatrana, Melanoides tuberculata (snail), Stenocypris major (ostracod), Chironomus javanus (midge larvae), Nais elinguis (annelid), and Duttaphrynus melanostictus (tadpole) to determine 96 h LC50 values for Fe, Pb, Ni, and Zn. The final acute value (FAV) for Fe, Pb, Ni, and Zn were 74.5, 17.0, 165, and 304.9 μg L−1, respectively. Using an estimated acute-to-chronic ratio (ACR) of 8.3, the value for final chronic value (FCV) was derived. Based on FAV and FCV, a criterion maximum concentration (CMC) and a criterion continuous concentration (CCC) for Fe, Pb, Ni, and Zn that are 37.2, 8.5, 82.5, and 152.4 μg L−1 and 9.0, 2.0, 19.9, and 36.7 μg L−1, respectively, were derived. The results of this study provide useful data for deriving national or local water quality criteria for Fe, Pb, Ni, and Zn based on aquatic biota in Malaysia. Based on LC50 values, this study indicated that N. elinguis, M. lanchesteri, N. elinguis, and R. sumatrana were the most sensitive to Fe, Pb, Ni, and Zn, respectively. PMID:22919358

Commercializing light-duty plug-in/plug-out hydrogen-fuel-cell vehicles: "Mobile electricity" technologies, early California household markets, and innovation management

NASA Astrophysics Data System (ADS)

Williams, Brett David

Starting from the premise that new consumer value must drive hydrogen-fuel-cell-vehicle (H2FCV) commercialization, a group of opportunities collectively called "Mobile Electricity" (Me-) is characterized. Me- redefines H2 FCVs as innovative products able to provide home recharging and mobile power, for example for tools, mobile activities, emergencies, and electric-grid-support services. To characterize such opportunities, this study first integrates and extends previous analyses of H2FCVs, plug-in hybrids, and vehicle-to-grid (V2G) power. It uses a new model to estimate zero-emission-power vs. zero-emission-driving tradeoffs, costs, and grid-support revenues for various electric-drive vehicle types and levels of infrastructure service. Next, the initial market potential for Me- enabled vehicles, such as H2FCVs and plug-in hybrids, is estimated by eliminating unlikely households from consideration for early adoption. 5.2 million of 33.9 million Californians in the 2000 Census live in households pre-adapted to Me-, 3.9 million if natural gas is required for home refueling. The possible sales base represented by this population is discussed. Several differences in demographic and other characteristics between the target market and the population as a whole are highlighted, and two issues related to the design of H2FCVs and their supporting infrastructure are discussed: vehicle range and home hydrogen refueling. These findings argue for continued investigation of this and similar target segments-which represent more efficient research populations for subsequent study by product designers and other decision-makers wishing to understand the early market dynamics facing Me- innovations. Next, Me-H2FCV commercialization issues are raised from the perspectives of innovation, product development, and strategic marketing. Starting with today's internalcombustion hybrids, this discussion suggests a way to move beyond the battery vs. fuel-cell zero-sum game and towards the development of integrated plug-in/plug-out hybrid platforms. H2FCVs are described as one possible extension of this Me- product platform for the supply of clean, high-power, and profitable Me- services as the technologies and markets mature. Finally, the major findings of this study are summarized and directions for future work discussed. Together, the parts of this Me- innovation assessment reveal an initially expensive and limited but compelling (and possibly necessary) set of opportunities to help drive H2FCV and other electric-drive-vehicle commercialization.

Project Ranking 2

DTIC Science & Technology

1986-05-01

CCI) Wq.4)O ’)0)𔃾 COND -) ( CXPWqWVD- - w 0 -M m (0 M -T ID’ig -- >0 fCV-- W IDO-C)O)C� ,,.III-I~n -- v Mori vDI 0) O)wcl-W..,ID f- to WIM4) (3O...en 0- 0000 - I-U .0J0LLAI * XU~L. - .3*fe*2-4)m Z -umeo-Z-a-In2 - ~ u w-m-391 42- 2048 % %’~4-0 --- l.0 nw w- 11 2~4..Z-4 n- -a0f~0* . am 0- X0 -U-K .4I

Dynamic functional connectivity of the default mode network tracks daydreaming.

PubMed

Kucyi, Aaron; Davis, Karen D

2014-10-15

Humans spend much of their time engaged in stimulus-independent thoughts, colloquially known as "daydreaming" or "mind-wandering." A fundamental question concerns how awake, spontaneous brain activity represents the ongoing cognition of daydreaming versus unconscious processes characterized as "intrinsic." Since daydreaming involves brief cognitive events that spontaneously fluctuate, we tested the hypothesis that the dynamics of brain network functional connectivity (FC) are linked with daydreaming. We determined the general tendency to daydream in healthy adults based on a daydreaming frequency scale (DDF). Subjects then underwent both resting state functional magnetic resonance imaging (rs-fMRI) and fMRI during sensory stimulation with intermittent thought probes to determine the occurrences of mind-wandering events. Brain regions within the default mode network (DMN), purported to be involved in daydreaming, were assessed for 1) static FC across the entire fMRI scans, and 2) dynamic FC based on FC variability (FCV) across 30s progressively sliding windows of 2s increments within each scan. We found that during both resting and sensory stimulation states, individual differences in DDF were negatively correlated with static FC between the posterior cingulate cortex and a ventral DMN subsystem involved in future-oriented thought. Dynamic FC analysis revealed that DDF was positively correlated with FCV within the same DMN subsystem in the resting state but not during stimulation. However, dynamic but not static FC, in this subsystem, was positively correlated with an individual's degree of self-reported mind-wandering during sensory stimulation. These findings identify temporal aspects of spontaneous DMN activity that reflect conscious and unconscious processes. Copyright © 2014 Elsevier Inc. All rights reserved.

Evaluating the virucidal efficacy of hydrogen peroxide vapour.

PubMed

Goyal, S M; Chander, Y; Yezli, S; Otter, J A

2014-04-01

Surface contamination has been implicated in the transmission of certain viruses, and surface disinfection can be an effective measure to interrupt the spread of these agents. To evaluate the in-vitro efficacy of hydrogen peroxide vapour (HPV), a vapour-phase disinfection method, for the inactivation of a number of structurally distinct viruses of importance in the healthcare, veterinary and public sectors. The viruses studied were: feline calicivirus (FCV, a norovirus surrogate); human adenovirus type 1; transmissible gastroenteritis coronavirus of pigs (TGEV, a severe acute respiratory syndrome coronavirus [SARS-CoV] surrogate); avian influenza virus (AIV); and swine influenza virus (SwIV). The viruses were dried on stainless steel discs in 20- or 40-μL aliquots and exposed to HPV produced by a Clarus L generator (Bioquell, Horsham, PA, USA) in a 0.2-m(3) environmental chamber. Three vaporized volumes of hydrogen peroxide were tested in triplicate for each virus: 25, 27 and 33 mL. No viable viruses were identified after HPV exposure at any of the vaporized volumes tested. HPV was virucidal (>4-log reduction) against FCV, adenovirus, TGEV and AIV at the lowest vaporized volume tested (25 mL). For SwIV, due to low virus titre on the control discs, >3.8-log reduction was shown for the 25-mL vaporized volume and >4-log reduction was shown for the 27-mL and 33-mL vaporized volumes. HPV was virucidal for structurally distinct viruses dried on surfaces, suggesting that HPV can be considered for the disinfection of virus-contaminated surfaces. Copyright © 2014 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Efficacy of Cinnamaldehyde Against Enteric Viruses and Its Activity After Incorporation Into Biodegradable Multilayer Systems of Interest in Food Packaging.

PubMed

Fabra, M J; Castro-Mayorga, J L; Randazzo, W; Lagarón, J M; López-Rubio, A; Aznar, R; Sánchez, G

2016-06-01

Cinnamaldehyde (CNMA), an organic compound that gives cinnamon its flavor and odor, was investigated for its virucidal activity on norovirus surrogates, murine norovirus (MNV) and feline calicivirus (FCV), and hepatitis A virus (HAV). Initially, different concentrations of CNMA (0.1, 0.5 and 1 %) were individually mixed with each virus at titers of ca. 6-7 log10 TCID50/ml and incubated 2 h at 4 and 37 °C. CNMA was effective in reducing the titers of norovirus surrogates in a dose-dependent manner after 2 h at 37 °C, while HAV titers were reduced by 1 log10 after treatment with 1 % of CNMA. When incubation time was extended, HAV titers were reduced by 3.4 and 2.7 log10 after overnight incubation at 37 °C with 1 and 0.5 % of CNMA, respectively. Moreover, this paper analyzed, for the first time, the antiviral activity of adding an active electrospun interlayer based on zein and CNMA to a polyhydroxybutyrate packaging material (PHB) in a multilayer form. Biodegradable multilayer systems prepared with 2.60 mg/cm(2) (~9.7 %) of CNMA completely inactivated FCV according to ISO 22196:2011, while MNV titers were reduced by 2.75 log10. When the developed multilayer films were evaluated after one month of preparation or at 25 °C, the antiviral activity was reduced as compared to freshly prepared multilayer films evaluated at 37 °C. The results show the excellent potential of this system for food contact applications as well as for active packaging technologies in order to maintain or extend food quality and safety.

Automatic detection of osteoporosis based on hybrid genetic swarm fuzzy classifier approaches

PubMed Central

Kavitha, Muthu Subash; Ganesh Kumar, Pugalendhi; Park, Soon-Yong; Huh, Kyung-Hoe; Heo, Min-Suk; Kurita, Takio; Asano, Akira; An, Seo-Yong

2016-01-01

Objectives: This study proposed a new automated screening system based on a hybrid genetic swarm fuzzy (GSF) classifier using digital dental panoramic radiographs to diagnose females with a low bone mineral density (BMD) or osteoporosis. Methods: The geometrical attributes of both the mandibular cortical bone and trabecular bone were acquired using previously developed software. Designing an automated system for osteoporosis screening involved partitioning of the input attributes to generate an initial membership function (MF) and a rule set (RS), classification using a fuzzy inference system and optimization of the generated MF and RS using the genetic swarm algorithm. Fivefold cross-validation (5-FCV) was used to estimate the classification accuracy of the hybrid GSF classifier. The performance of the hybrid GSF classifier has been further compared with that of individual genetic algorithm and particle swarm optimization fuzzy classifiers. Results: Proposed hybrid GSF classifier in identifying low BMD or osteoporosis at the lumbar spine and femoral neck BMD was evaluated. The sensitivity, specificity and accuracy of the hybrid GSF with optimized MF and RS in identifying females with a low BMD were 95.3%, 94.7% and 96.01%, respectively, at the lumbar spine and 99.1%, 98.4% and 98.9%, respectively, at the femoral neck BMD. The diagnostic performance of the proposed system with femoral neck BMD was 0.986 with a confidence interval of 0.942–0.998. The highest mean accuracy using 5-FCV was 97.9% with femoral neck BMD. Conclusions: The combination of high accuracy along with its interpretation ability makes this proposed automatic system using hybrid GSF classifier capable of identifying a large proportion of undetected low BMD or osteoporosis at its early stage. PMID:27186991

Direct-hydrogen-fueled proton-exchange-membrane fuel cell system for transportation applications. Hydrogen vehicle safety report

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

Thomas, C.E.

1997-05-01

This report reviews the safety characteristics of hydrogen as an energy carrier for a fuel cell vehicle (FCV), with emphasis on high pressure gaseous hydrogen onboard storage. The authors consider normal operation of the vehicle in addition to refueling, collisions, operation in tunnels, and storage in garages. They identify the most likely risks and failure modes leading to hazardous conditions, and provide potential countermeasures in the vehicle design to prevent or substantially reduce the consequences of each plausible failure mode. They then compare the risks of hydrogen with those of more common motor vehicle fuels including gasoline, propane, and naturalmore » gas.« less

PROCEDURES FOR THE DERIVATION OF EQUILIBRIUM ...

EPA Pesticide Factsheets

This equilibrium partitioning sediment benchmark (ESB) document describes procedures to derive concentrations for 32 nonionic organic chemicals in sediment which are protective of the presence of freshwater and marine benthic organisms. The equilibrium partitioning (EqP) approach was chosen because it accounts for the varying biological availability of chemicals in different sediments and allows for the incorporation of the appropriate biological effects concentration. This provides for the derivation of benchmarks that are causally linked to the specific chemical, applicable across sediments, and appropriately protective of benthic organisms. EqP can be used to calculate ESBs for any toxicity endpoint for which there are water-only toxicity data; it is not limited to any single effect endpoint. For the purposes of this document, ESBs for 32 nonionic organic chemicals, including several low molecular weight aliphatic and aromatic compounds, pesticides, and phthalates, were derived using Final Chronic Values (FCV) from Water Quality Criteria (WQC) or Secondary Chronic Values (SCV) derived from existing toxicological data using the Great Lakes Water Quality Initiative (GLI) or narcosis theory approaches. These values are intended to be the concentration of each chemical in water that is protective of the presence of aquatic life. For nonionic organic chemicals demonstrating a narcotic mode of action, ESBs derived using the GLI approach specifically for fres

Serosurvey of viral infections in free-ranging Namibian cheetahs (Acinonyx jubatus).

PubMed

Munson, Linda; Marker, Laurie; Dubovi, Edward; Spencer, Jennifer A; Evermann, James F; O'Brien, Stephen J

2004-01-01

Cheetahs (Acinonyx jubatus) in captivity have unusually high morbidity and mortality from infectious diseases, a trait that could be an outcome of population homogeneity or the immunomodulating effects of chronic stress. Free-ranging Namibian cheetahs share ancestry with captive cheetahs, but their susceptibility to infectious diseases has not been investigated. The largest remaining population of free-ranging cheetahs resides on Namibian farmlands, where they share habitat with domestic dogs and cats known to carry viruses that affect cheetah health. To assess the extent to which free-ranging cheetahs are exposed to feline and canine viruses, sera from 81 free-ranging cheetahs sampled between 1992 and 1998 were evaluated for antibodies against canine distemper virus (CDV), feline coronavirus (feline infectious peritonitis virus; FCoV/ FIPV), feline herpesvirus 1 (FHV1), feline panleukopenia virus (FPV), feline immunodeficiency virus (FIV), and feline calicivirus (FCV) and for feline leukemia virus (FeLV) antigens. Antibodies against CDV, FCoV/FIPV, FHV1, FPV, and FCV were detected in 24, 29, 12, 48, and 65% of the free-ranging population, respectively, although no evidence of viral disease was present in any animal at the time of sample collection. Neither FIV antibodies nor FeLV antigens were present in any free-ranging cheetah tested. Temporal variation in FCoV/FIPV seroprevalence during the study period suggested that this virus is not endemic in the free-ranging population. Antibodies against CDV were detected in cheetahs of all ages sampled between 1995 and 1998, suggesting the occurrence of an epidemic in Namibia during the time when CDV swept through other parts of sub-Saharan Africa. This evidence in free-ranging Namibian cheetahs of exposure to viruses that cause severe disease in captive cheetahs should direct future guidelines for translocations, including quarantine of seropositive cheetahs and preventing contact between cheetahs and domestic pets.

Reduction of Enteric Viruses by Blueberry Juice and Blueberry Proanthocyanidins.

PubMed

Joshi, Snehal S; Howell, Amy B; D'Souza, Doris H

2016-12-01

Blueberry and blueberry extracts are known for their health benefits and antimicrobial properties. Natural therapeutic or preventive options to decrease the incidences of foodborne viral illnesses are becoming popular and being researched. This study aimed to determine the antiviral effects of blueberry juice (BJ) and blueberry proanthocyanidins (BB-PAC, B-type PAC structurally different from A-type PAC found in cranberries) against the infectivity of hepatitis A virus (HAV) and human norovirus surrogates (feline calicivirus (FCV-F9) and murine norovirus (MNV-1)) at 37 °C over 24 h using standard plaque assays. Viruses at ~5 log PFU/ml were mixed with equal volumes of BJ (pH 2.8), neutralized BJ (pH 7.0), BB-PAC (1, 2, 4, and 10 mg/ml), malic acid (pH 3.0), or phosphate-buffered saline (pH 7.2) and incubated over 24 h at 37 °C. Each experiment was carried out in duplicate and replicated thrice. FCV-F9 titers were found to be reduced to undetectable levels with 1 and 2 mg/ml BB-PAC after 5 min, with 0.5 mg/ml BB-PAC after 1-h, and with BJ after 3-h. MNV-1 titers were reduced to undetectable levels after 3 h with 1, 2, and 5 mg/ml BB-PAC and after 6 h with BJ. HAV titers were reduced to undetectable levels after 30 min with 2 and 5 mg/ml BB-PAC, after 3 h with 1 mg/ml BB-PAC, and by ~2 log PFU/ml with BJ after 24-h. BB-PAC shows preventive potential against infection by the tested enteric viruses in a dose- and time-dependent manner, although further in vitro studies in model food systems and in vivo studies using animal models are warranted.

Blueberry proanthocyanidins against human norovirus surrogates in model foods and under simulated gastric conditions.

PubMed

Joshi, Snehal; Howell, Amy B; D'Souza, Doris H

2017-05-01

Blueberry proanthocyanidins (B-PAC) are known to decrease titers of human norovirus surrogates in vitro. The application of B-PAC as therapeutic or preventive options against foodborne viral illness needs to be determined using model foods and simulated gastric conditions in vitro. The objective of this study was to evaluate the antiviral effect of B-PAC in model foods (apple juice (AJ) and 2% reduced fat milk) and simulated gastrointestinal fluids against cultivable human norovirus surrogates (feline calicivirus; FCV-F9 and murine norovirus; MNV-1) over 24 h at 37 °C. Equal amounts of each virus (5 log PFU/ml) was mixed with B-PAC (1, 2 and 5 mg/ml) prepared either in AJ, or 2% milk, or simulated gastric fluids and incubated over 24 h at 37 °C. Controls included phosphate buffered saline, malic acid (pH 7.2), AJ, 2% milk or simulated gastric and intestinal fluids incubated with virus over 24 h at 37 °C. The tested viruses were reduced to undetectable levels within 15 min with B-PAC (1, 2 and 5 mg/ml) in AJ (pH 3.6). However, antiviral activity of B-PAC was reduced in milk. FCV-F9 was reduced by 0.4 and 1.09 log PFU/ml with 2 and 5 mg/ml B-PAC in milk, respectively and MNV-1 titers were reduced by 0.81 log PFU/ml with 5 mg/ml B-PAC in milk after 24 h. B-PAC at 5 mg/ml in simulated intestinal fluid reduced titers of the tested viruses to undetectable levels within 30 min. Overall, these results show the potential of B-PAC as preventive and therapeutic options for foodborne viral illnesses. Copyright © 2016. Published by Elsevier Ltd.

Inactivation of Viruses and Bacteriophages as Models for Swine Hepatitis E Virus in Food Matrices.

PubMed

Emmoth, Eva; Rovira, Jordi; Rajkovic, Andreja; Corcuera, Elena; Wilches Pérez, Diego; Dergel, Irene; Ottoson, Jakob R; Widén, Frederik

2017-03-01

Hepatitis E virus has been recognised as a food-borne virus hazard in pork products, due to its zoonotic properties. This risk can be reduced by adequate treatment of the food to inactivate food-borne viruses. We used a spectrum of viruses and bacteriophages to evaluate the effect of three food treatments: high pressure processing (HPP), lactic acid (LA) and intense light pulse (ILP) treatments. On swine liver at 400 MPa for 10 min, HPP gave log 10 reductions of ≥4.2, ≥5.0 and 3.4 for feline calicivirus (FCV) 2280, FCV wildtype (wt) and murine norovirus 1 (MNV 1), respectively. Escherichia coli coliphage ϕX174 displayed a lower reduction of 1.1, while Escherichia coli coliphage MS2 was unaffected. For ham at 600 MPa, the corresponding reductions were 4.1, 4.4, 2.9, 1.7 and 1.3 log 10 . LA treatment at 2.2 M gave log 10 reductions in the viral spectrum of 0.29-2.1 for swine liver and 0.87-3.1 for ham, with ϕX174 and MNV 1, respectively, as the most stable microorganisms. The ILP treatment gave log 10 reductions of 1.6-2.8 for swine liver, 0.97-2.2 for ham and 1.3-2.3 for sausage, at 15-60 J cm -2 , with MS2 as the most stable microorganism. The HPP treatment gave significantly (p < 0.05) greater virus reduction on swine liver than ham for the viruses at equivalent pressure/time combinations. For ILP treatment, reductions on swine liver were significantly (p < 0.05) greater than on ham for all microorganisms. The results presented here could be used in assessments of different strategies to protect consumers against virus contamination and in advice to food producers. Conservative model indicators for the pathogenic viruses could be suggested.

Electric Vehicle Service Personnel Training Program

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

Bernstein, Gerald

As the share of hybrid, plug-in hybrid (PHEV), electric (EV) and fuel-cell (FCV) vehicles grows in the national automotive fleet, an entirely new set of diagnostic and technical skills needs to be obtained by the maintenance workforce. Electrically-powered vehicles require new diagnostic tools, technique and vocabulary when compared to existing internal combustion engine-powered models. While the manufacturers of these new vehicles train their own maintenance personnel, training for students, independent working technicians and fleet operators is less focused and organized. This DOE-funded effort provided training to these three target groups to help expand availability of skills and to provide moremore » competition (and lower consumer cost) in the maintenance of these hybrid- and electric-powered vehicles. Our approach was to start locally in the San Francisco Bay Area, one of the densest markets in the United States for these types of automobiles. We then expanded training to the Los Angeles area and then out-of-state to identify what types of curriculum was appropriate and what types of problems were encountered as training was disseminated. The fact that this effort trained up to 800 individuals with sessions varying from 2- day workshops to full-semester courses is considered a successful outcome. Diverse programs were developed to match unique time availability and educational needs of each of the three target audiences. Several key findings and observations arising from this effort include: • Recognition that hybrid and PHEV training demand is immediate; demand for EV training is starting to emerge; while demand for FCV training is still over the horizon • Hybrid and PHEV training are an excellent starting point for all EV-related training as they introduce all the basic concepts (electric motors, battery management, controllers, vocabulary, testing techniques) that are needed for all EVs, and these skills are in-demand in today’s market. • Faculty training is widely available and can be relatively quickly achieved. Equipment availability (vehicles, specialized tools, diagnostic software and computers) is a bigger challenge for funding-constrained colleges. • A computer-based emulation system that would replicate vehicle and diagnostic software in one package is a training aid that would have widespread benefit, but does not appear to exist. This need is further described at the end of Section 6.5. The benefits of this project are unique to each of the three target audiences. Students have learned skills they will use for the remainder of their careers; independent technicians can now accept customers who they previously needed to turn away due to lack of familiarity with hybrid systems; and fleet maintenance personnel are able to lower costs by undertaking work in-house that they previously needed to outsource. The direct job impact is estimated at 0.75 FTE continuously over the 3 ½ -year duration of the grant.« less

Humoral response to calicivirus in captive tigers given a dual-strain vaccine.

PubMed

Harrison, Tara M; Harrison, Scott H; Sikarskie, James G; Armstrong, Douglas

2014-03-01

The current feline vaccine with a single strain of calicivirus has been used for captive tigers, yet it may not protect against virulent systemic calicivirus infections. A cross-institutional study investigated the humoral response to a new dual-strain, killed-virus calicivirus vaccine for nine captive tigers. The subspecies of these tigers were Amur (Panthera tigris altaica), Bengal (Panthera tigris tigris), and Malayan (Panthera tigris jacksoni). Serum neutralization titers for virulent feline calicivirus strain FCV-DD1 were higher following dual-strain vaccine administration. There were no reports of adverse vaccine reactions. Dual-strain vaccination may afford broadened cross-protection against different calicivirus strains and is desirable to reduce the risk of virulent systemic calicivirus disease in tigers.

Failure Analysis of Fractured Poppet from Space Shuttle Orbiter Flow Control Valve

NASA Technical Reports Server (NTRS)

Russell, Richard

2010-01-01

This slide presentation reviews the failure analysis of a fractured poppet from a flow control valve (FCV) used on the space shuttle. This presentation has focused on the laboratory analysis of the failed hardware. The use of Scanning electron fractography during the investigation led to the conclusion that the poppet failed due to fatigue cracking that, most likely, occurred under changing loading conditions. The initial investigation led to a more thorough test of poppets that had been retired, this testing led to the conclusion that the thumbnail cracks in the flight hardware had existed for the life of the shuttle program. This led to a program to develop an eddy current technique that was capable of detecting small very tight cracks.

Space Shuttle Main Propulsion System Gaseous Hydrogen Flow Control Valve Poppet Failure

NASA Technical Reports Server (NTRS)

Zeitler, Rick

2010-01-01

The presentation provides background information pertinent to the MPS GH2 Flow Control Valve Poppet failure which occurred on the Space Shuttle Endeavour during STS-126 flight. The presentation provides general MPS system operating information which is pertinent to understanding the failure causes and affects. The presentation provides additional background information on the operating environment in which the FCV functions and basic design history of the flow control valve. The presentation provides an overview of the possible flight failure modes and a brief summary of the flight rationale which was developed for this failure event. This presentation is an introductory presentation to 3 other speakers at the conference who will be speaking on M&P aspects of the investigation, non destructive inspection techniques development, and particle impact testing.

Comparison of virucidal activity of alcohol-based hand sanitizers versus antimicrobial hand soaps in vitro and in vivo.

PubMed

Steinmann, J; Paulmann, D; Becker, B; Bischoff, B; Steinmann, E; Steinmann, J

2012-12-01

Three ethanol-based sanitizers were compared with three antimicrobial liquid soaps for their efficacy to inactivate polio-, adeno-, vaccinia- and bovine viral diarrhoea virus (BVDV) as well as feline calicivirus (FCV) and murine norovirus (MNV) as surrogates for human norovirus in a suspension test. Additionally, sanitizers and soaps were examined against MNV in a modified fingerpad method. All sanitizers sufficiently inactivated the test viruses in the suspension test whereas two soaps were active only against vaccinia virus and BVDV. In the modified fingerpad test a povidone-iodine-containing soap was superior to the sanitizers whereas the other two soaps showed no activity. Copyright © 2012 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Design, synthesis, and biological evaluation of novel iso-D-2',3'-dideoxy-3'-fluorothianucleoside derivatives.

PubMed

Kim, Kyung Ran; Moon, Hyung Ryong; Park, Ah-Young; Chun, Moon Woo; Jeong, Lak Shin

2007-01-01

Novel iso-d-2',3'-dideoxythianucleoside derivatives 1-4 were designed and asymmetrically synthesized as a bioisostere of lamivudine to search for new anti-HIV agents. The information about using sulfur participation occurred on DAST fluorination and Mitsunobu reaction will be of great help in synthesizing sulfur-containing compounds. Final compounds 1-4 were evaluated against HIV-1 and 2, HSV-1 and 2, EMCV, Cox. B3, VSV, FluA (Taiwan), FluA (Johan.), FCV, and FIP. Only cytosine analogue 3 showed a potent anti-VSV activity (EC(50)=9.43microg/mL). This result implies that iso-2',3'-dideoxy sugar templates might play a role of a sugar surrogate of nucleosides for the development of anti-RNA virus agent.

Tetramethylbenzidine method for monitoring the free available chlorine and microbicidal activity of chlorite-based sanitizers under organic-matter-rich environments.

PubMed

Yamaoka, H; Nakayama-Imaohji, H; Horiuchi, I; Yamasaki, H; Nagao, T; Fujita, Y; Maeda, H; Goda, H; Kuwahara, T

2016-01-01

Chlorine is a principal disinfectant for food and environmental sanitation. Monitoring of free available chlorine (FAC) is essential for ensuring the efficacy of food disinfection processes that rely on chlorine. N,N-diethyl-p-phenylenediamine (DPD) is commonly used for FAC monitoring. However, here, we show that upon contact with bovine serum albumin (BSA) or broiler carcasses, chlorite (HClO2 )-based sanitizers acquire a pink colour, which can interfere with measurement of oxidized DPD absorbance at 513-550 nm. Alternatively, the pink colour did not interfere with 3,3',5,5'-tetramethylbenzidine (TMB)-based FAC monitoring. The FAC levels of NaClO and weakly acidified chlorous acid water (WACAW) were first adjusted by the TMB method and the killing activity of these sanitizers towards methicillin-resistant Staphylococcus aureus (MRSA) and feline calicivirus (FCV) was compared in the presence or absence of 0·5% BSA. At 200 ppm FAC, NaClO lost its bactericidal activity against MRSA after 10-min incubation with 0·5% BSA. Meanwhile, under the same conditions WACAW reduced the number of bacteria to below the detection limit. Similar results were obtained with FCV, indicating that the chlorite-based WACAW sanitizer is relatively stable under organic-matter-rich conditions. Moreover, TMB is suitable for in situ FAC monitoring of chlorite-based sanitizers in food and environmental disinfection processes. For practical applications of chlorine in food processing, monitoring of FAC is critical to validate disinfection efficacy. In this study we found that chlorite-based sanitizers acquired a pink colour upon contact with BSA or broiler carcasses. This pink colour interfered with FAC monitoring by methods that measure oxidized N,N-diethyl-p-phenylenediamine absorbance between 513-550 nm. Alternatively, FAC levels of chlorite-based sanitizers could be monitored using the absorbance of 3,3',5,5'-tetramethylbenzidine at 650 nm, which does not overlap with the acquired pink colour. These data provide valuable information for safety management of disinfection processes that use chlorite-based sanitizers. © 2015 The Society for Applied Microbiology.

The effect of losartan and carvedilol on renal haemodynamics and altered metabolism in fructose-fed Sprague-Dawley rats.

PubMed

Abdulla, Mohammed H; Sattar, Munavvar A; Abdullah, Nor A; Johns, Edward J

2012-09-01

The aim of this study is to assess the effects of losartan and carvedilol on metabolic parameters and renal haemodynamic responses to angiotensin II (Ang II) and adrenergic agonists in the model of fructose-fed rat. Thirty-six Sprague-Dawley rats were fed for 8 weeks either 20% fructose solution (F) or tap water (C) ad libitum. F or C group received either losartan or carvedilol (10 mg/kg p.o.) daily for the last 3 weeks of the study (FL and L) and (FCV and CV), respectively, then in acute studies the renal vasoconstrictor actions of Ang II, noradrenaline (NA), phenylephrine (PE) and methoxamine (ME) were determined. Data, mean±SEM were analysed using ANOVA with significance at P <0.05. Losartan and carvedilol decreased the area under the glucose tolerance curve of the fructose-fed group. The responses (%) to NA, PE, ME and Ang II in F were lower (P <0.05) than C (F vs. C, 17±2 vs. 38±3; 24±2 vs. 48±2; 12±2 vs. 34±2; 17±2 vs. 26±2), respectively. L had higher (P <0.05) responses to NA and PE while CV had blunted (P <0.05) responses to NA, PE and Ang II compared to C (L, CV vs. C, 47±3, 9±2 vs. 38±3; 61±3, 29±3 vs. 48±2; 16±3, 4±3 vs. 26±2), respectively. FL but not FCV group had enhanced (P <0.05) responses to NA, PE and ME compared to F (FL vs. F, 33±3 vs. 17±2; 45±3 vs. 24±2; 26±3 vs. 12±2), respectively. Losartan and carvedilol had an important ameliorating effect on fructose-induced insulin resistance. Losartan treatment could be an effective tool to restore normal vascular reactivity in the renal circulation of the fructose-fed rat.

Characterization of a continuous feline mammary epithelial cell line susceptible to feline epitheliotropic viruses.

PubMed

Pesavento, Patricia; Liu, Hongwei; Ossiboff, Robert J; Stucker, Karla M; Heymer, Anna; Millon, Lee; Wood, Jason; van der List, Deborah; Parker, John S L

2009-04-01

Mucosal epithelial cells are the primary targets for many common viral pathogens of cats. Viral infection of epithelia can damage or disrupt the epithelial barrier that protects underlying tissues. In vitro cell culture systems are an effective means to study how viruses infect and disrupt epithelial barriers, however no true continuous or immortalized feline epithelial cell culture lines are available. A continuous cell culture of feline mammary epithelial cells (FMEC UCD-04-2) that forms tight junctions with high transepithelial electrical resistance (>2000Omegacm(-1)) 3-4 days after reaching confluence was characterized. In addition, it was shown that FMECs are susceptible to infection with feline calicivirus (FCV), feline herpesvirus (FHV-1), feline coronavirus (FeCoV), and feline panleukopenia virus (FPV). These cells will be useful for studies of feline viral disease and for in vitro studies of feline epithelia.

Les aspects des frottis cervico-vaginaux chez les femmes vivants avec le VIH suivies à Thiès/Sénégal et association avec le degré d'immunodépression

PubMed Central

Bammo, Mariama; Dioussé, Pauline; Thiam, Marietou; Diop, Madoky Maguatte; Berthe, Adama; Faye, Flugence Abdou; Diallo, Thierno Abdoul Aziz; Sarr, Fatou Seck; Dione, Haby; Toure, Papa Souleymane; Diop, Bernard Marcel; Ka, Mamadou Mortalla

2015-01-01

De nombreuses études ont démontré que les femmes infectées par le VIH ont un risque accru de survenue de néoplasies cervicales intra épithéliales. L'association entre les deux affections étant bidirectionnelle, l'objectif était de décrire les anomalies cervicales chez les femmes séropositives au virus de l'immunodéficience humaine (VIH), de rechercher des facteurs associés et de proposer des recommandations en termes de suivi de ces femmes. Il s'agissait d'une étude transversale, multicentrique recensant l'ensemble des frottis cervico-vaginaux (FCV) et des colposcopies des patientes infectées par le VIH entre 2012 et 2014 dans les services de dermatologie de Thiès et de Mbour. Les données étaient recueillies et analysées par le logiciel EPI Info 2012 version 3.5.4. Les tests statistiques ont été effectués avec un seuil de significativité p <0,05. Etaient inclus 125 patientes. L’âge moyen était de 38,98 ± 10.2 ans [20-77]. Il n'y avait aucun signe d'appels dans 82.4%. Le FCV était normal dans 32.8%, inflammatoire dans 44.8%. Les anomalies cytologiques concernaient 22,4% dont, ASC-H (suspicion de lésions de haut grade: 2.4%), LSIL (lésions de bas grade: 8.8%), HSIL (lésions de haut grade: 4%). Leur majorité (60.7%) avaient un taux de CD4 < 500 et étaient au stade 3 de l'OMS dans 64.3%; la biopsie montrait une dysplasie sévère chez 37.5% des patientes ayant pu réaliser cet examen. Deux patientes ont bénéficié d'un traitement curatif notamment l'exérèse chirurgicale. La survenue de dysplasies cervicales même précoces semble être associée à un stade avancé de l'infection VIH. Un dépistage et un traitement précoces sont absolument nécessaires. PMID:26834915

Measuring the distribution of equity in terms of energy, environmental, and economic costs in the fuel cycles of alternative fuel vehicles with hydrogen pathway scenarios

NASA Astrophysics Data System (ADS)

Meyer, Patrick E.

Numerous analyses exist which examine the energy, environmental, and economic tradeoffs between conventional gasoline vehicles and hydrogen fuel cell vehicles powered by hydrogen produced from a variety of sources. These analyses are commonly referred to as "E3" analyses because of their inclusion of Energy, Environmental, and Economic indicators. Recent research as sought a means to incorporate social Equity into E3 analyses, thus producing an "E4" analysis. However, E4 analyses in the realm of energy policy are uncommon, and in the realm of alternative transportation fuels, E4 analyses are extremely rare. This dissertation discusses the creation of a novel E4 simulation tool usable to weigh energy, environmental, economic, and equity trade-offs between conventional gasoline vehicles and alternative fuel vehicles, with specific application to hydrogen fuel cell vehicles. The model, dubbed the F uel Life-cycle Analysis of Solar Hydrogen -- Energy, Environment, Economic & Equity model, or FLASH-E4, is a total fuel-cycle model that combines energy, environmental, and economic analysis methodologies with the addition of an equity analysis component. The model is capable of providing results regarding total fuel-cycle energy consumption, emissions production, energy and environmental cost, and level of social equity within a population in which low-income drivers use CGV technology and high-income drivers use a number of advanced hydrogen FCV technologies. Using theories of equity and social indicators conceptually embodied in the Lorenz Curve and Gini Index, the equity of the distribution of societal energy and environmental costs are measured for a population in which some drivers use CGVs and other drivers use FCVs. It is found, based on baseline input data representative of the United States (US), that the distribution of energy and environmental costs in a population in which some drivers use CGVs and other drivers use natural gas-based hydrogen FCVs can be moderately inequitable. However, the distribution of energy and environmental costs in a population in which some drivers use CGVs and other drivers use solar-electrolysis-based FCVs can be extremely inequitable. Further, it is found that the method of production and delivery of hydrogen (i.e. centralized production or refueling station-based production) can have an impact on the equity of energy and environmental costs. The implications of these results are interesting, in that wealthy people purchase FCVs that have high upfront costs and very low societal energy and environmental costs. Simultaneously, however, low-income people purchase CGVs that have low upfront costs and very high societal energy and environmental costs. In this situation, due to the high-polluting nature of CGV technology in relation to FCV technology, CGV drivers account for more than their equitable share of energy and environmental costs. Scenarios are conducted which explore modifications of assumptions, such as the price of oil, price of natural gas, cost to offset emissions, consumer purchase price of FCVs, and the level of taxation on the cost streams. Among other findings, it is found that altering the purchase price of an FCV has the greatest impact on social equity whereas altering the cost to offset fuel-cycle emissions has the least impact, indicating that policy mechanisms aimed at incentivizing FCVs may have a more positive impact on social equity than policies aimed at mitigating emissions. Based on the results of the scenario analysis, policy recommendations are formulated which seek to maximize social equity in populations in which not all drivers use the same vehicular technology. The policies, if implemented as a single portfolio, would assist a systematic deviation away from the fossil fuel energy economy while ensuring that social equity is preserved to the greatest degree possible. (Abstract shortened by UMI.)

Hydrogen Fuel Cell Electric Vehicle Learning Demonstration | Hydrogen and

Science.gov Websites

Fuel Cells | NREL Fuel Cell Electric Vehicle Learning Demonstration Hydrogen Fuel Cell Electric Vehicle Learning Demonstration Initiated in 2004, DOE's Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project-later dubbed the Fuel Cell Electric Vehicle (FCEV) Learning Demonstration

Recovery of interior brackish marshes seven years after the chalk point oil spill.

PubMed

Michel, Jacqueline; Nixon, Zachary; Dahlin, Jeffrey; Betenbaugh, David; White, Mark; Burton, Dennis; Turley, Steven

2009-07-01

Seven years after the April 2000 spill of 140,000 gallons of a mixture of No. 6 and No. 2 fuel oils in the Patuxent River, Maryland, heavily oiled brackish marshes showed continuing effects. Stem density and stem height were significantly lower in oiled versus unoiled sites for Spartina alterniflora but not Spartina cynosuroides habitats. In contrast, belowground biomass was significantly lower in S. cynosuroides habitats but not S. alterniflora habitats. Total PAH concentrations were up to 453 mg/kg in surficial soils (0-10 cm) and 2921 mg/kg with depth (10-20 cm). The oil had lost 22-76% of its initial PAH content after seven years, although the oil in marsh soils has undergone little to no additional weathering since Fall 2000. Based on amphipod acute toxicity tests and sediment quality guidelines, 25% of the soils in the marsh are expected to be toxic (ESB-TU(FCV) values>3.0; P(Max)>0.65).

Social learning of fear and safety is determined by the demonstrator's racial group.

PubMed

Golkar, Armita; Castro, Vasco; Olsson, Andreas

2015-01-01

Social learning offers an efficient route through which humans and other animals learn about potential dangers in the environment. Such learning inherently relies on the transmission of social information and should imply selectivity in what to learn from whom. Here, we conducted two observational learning experiments to assess how humans learn about danger and safety from members ('demonstrators') of an other social group than their own. We show that both fear and safety learning from a racial in-group demonstrator was more potent than learning from a racial out-group demonstrator. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Interactions between Human Norovirus Surrogates and Acanthamoeba spp.

PubMed Central

Hsueh, Tun-Yun

2015-01-01

Human noroviruses (HuNoVs) are the most common cause of food-borne disease outbreaks, as well as virus-related waterborne disease outbreaks in the United States. Here, we hypothesize that common free-living amoebae (FLA)—ubiquitous in the environment, known to interact with pathogens, and frequently isolated from water and fresh produce—could potentially act as reservoirs of HuNoV and facilitate the environmental transmission of HuNoVs. To investigate FLA as reservoirs for HuNoV, the interactions between two Acanthamoeba species, A. castellanii and A. polyphaga, as well as two HuNoV surrogates, murine norovirus type 1 (MNV-1) and feline calicivirus (FCV), were evaluated. The results showed that after 1 h of amoeba-virus incubation at 25°C, 490 and 337 PFU of MNV-1/ml were recovered from A. castellanii and A. polyphaga, respectively, while only few or no FCVs were detected. In addition, prolonged interaction of MNV-1 with amoebae was investigated for a period of 8 days, and MNV-1 was demonstrated to remain stable at around 200 PFU/ml from day 2 to day 8 after virus inoculation in A. castellanii. Moreover, after a complete amoeba life cycle (i.e., encystment and excystment), infectious viruses could still be detected. To determine the location of virus associated with amoebae, immunofluorescence experiments were performed and showed MNV-1 transitioning from the amoeba surface to inside the amoeba over a 24-h period. These results are significant to the understanding of how HuNoVs may interact with other microorganisms in the environment in order to aid in its persistence and survival, as well as potential transmission in water and to vulnerable food products such as fresh produce. PMID:25841006

34 CFR 425.1 - What is the Demonstration Projects for the Integration of Vocational and Academic Learning Program?

Code of Federal Regulations, 2013 CFR

2013-07-01

... of Vocational and Academic Learning Program? 425.1 Section 425.1 Education Regulations of the Offices... EDUCATION DEMONSTRATION PROJECTS FOR THE INTEGRATION OF VOCATIONAL AND ACADEMIC LEARNING PROGRAM General § 425.1 What is the Demonstration Projects for the Integration of Vocational and Academic Learning...

34 CFR 425.1 - What is the Demonstration Projects for the Integration of Vocational and Academic Learning Program?

Code of Federal Regulations, 2011 CFR

2011-07-01

... of Vocational and Academic Learning Program? 425.1 Section 425.1 Education Regulations of the Offices... EDUCATION DEMONSTRATION PROJECTS FOR THE INTEGRATION OF VOCATIONAL AND ACADEMIC LEARNING PROGRAM General § 425.1 What is the Demonstration Projects for the Integration of Vocational and Academic Learning...

34 CFR 425.1 - What is the Demonstration Projects for the Integration of Vocational and Academic Learning Program?

Code of Federal Regulations, 2012 CFR

2012-07-01

... of Vocational and Academic Learning Program? 425.1 Section 425.1 Education Regulations of the Offices... EDUCATION DEMONSTRATION PROJECTS FOR THE INTEGRATION OF VOCATIONAL AND ACADEMIC LEARNING PROGRAM General § 425.1 What is the Demonstration Projects for the Integration of Vocational and Academic Learning...

34 CFR 425.1 - What is the Demonstration Projects for the Integration of Vocational and Academic Learning Program?

Code of Federal Regulations, 2014 CFR

2014-07-01

... of Vocational and Academic Learning Program? 425.1 Section 425.1 Education Regulations of the Offices... EDUCATION DEMONSTRATION PROJECTS FOR THE INTEGRATION OF VOCATIONAL AND ACADEMIC LEARNING PROGRAM General § 425.1 What is the Demonstration Projects for the Integration of Vocational and Academic Learning...

Deep imitation learning for 3D navigation tasks.

PubMed

Hussein, Ahmed; Elyan, Eyad; Gaber, Mohamed Medhat; Jayne, Chrisina

2018-01-01

Deep learning techniques have shown success in learning from raw high-dimensional data in various applications. While deep reinforcement learning is recently gaining popularity as a method to train intelligent agents, utilizing deep learning in imitation learning has been scarcely explored. Imitation learning can be an efficient method to teach intelligent agents by providing a set of demonstrations to learn from. However, generalizing to situations that are not represented in the demonstrations can be challenging, especially in 3D environments. In this paper, we propose a deep imitation learning method to learn navigation tasks from demonstrations in a 3D environment. The supervised policy is refined using active learning in order to generalize to unseen situations. This approach is compared to two popular deep reinforcement learning techniques: deep-Q-networks and Asynchronous actor-critic (A3C). The proposed method as well as the reinforcement learning methods employ deep convolutional neural networks and learn directly from raw visual input. Methods for combining learning from demonstrations and experience are also investigated. This combination aims to join the generalization ability of learning by experience with the efficiency of learning by imitation. The proposed methods are evaluated on 4 navigation tasks in a 3D simulated environment. Navigation tasks are a typical problem that is relevant to many real applications. They pose the challenge of requiring demonstrations of long trajectories to reach the target and only providing delayed rewards (usually terminal) to the agent. The experiments show that the proposed method can successfully learn navigation tasks from raw visual input while learning from experience methods fail to learn an effective policy. Moreover, it is shown that active learning can significantly improve the performance of the initially learned policy using a small number of active samples.

Combining Active Learning with Service Learning: A Student-Driven Demonstration Project.

ERIC Educational Resources Information Center

Hatcher-Skeers, Mary; Aragon, Ellen

2002-01-01

Describes a project that integrates active learning into service learning targeting both college students and middle schools students wherein college students perform chemical demonstrations for middle school students. (YDS)

Trial-and-error copying of demonstrated actions reveals how fledglings learn to ‘imitate’ their mothers

PubMed Central

Lotem, Arnon

2017-01-01

Understanding how humans and other animals learn to perform an act from seeing it done has been a major challenge in the study of social learning. To determine whether this ability is based on ‘true imitation’, many studies have applied the two-action experimental paradigm, examining whether subjects learn to perform the specific action demonstrated to them. Here, we show that the insights gained from animals' success in two-action experiments may be limited, and that a better understanding is achieved by monitoring subjects' entire behavioural repertoire. Hand-reared house sparrows that followed a model of a mother demonstrator were successful in learning to find seeds hidden under a leaf, using the action demonstrated by the mother (either pushing the leaf or pecking it). However, they also produced behaviours that had not been demonstrated but were nevertheless related to the demonstrated act. This finding suggests that while the learners were clearly influenced by the demonstrator, they did not accurately imitate her. Rather, they used their own behavioural repertoire, gradually fitting it to the demonstrated task solution through trial and error. This process is consistent with recent views on how animals learn to imitate, and may contribute to a unified process-level analysis of social learning mechanisms. PMID:28228516

34 CFR 425.1 - What is the Demonstration Projects for the Integration of Vocational and Academic Learning Program?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 34 Education 3 2010-07-01 2010-07-01 false What is the Demonstration Projects for the Integration... EDUCATION DEMONSTRATION PROJECTS FOR THE INTEGRATION OF VOCATIONAL AND ACADEMIC LEARNING PROGRAM General § 425.1 What is the Demonstration Projects for the Integration of Vocational and Academic Learning...

Variability in University Students' Use of Technology: An "Approaches to Learning" Perspective

ERIC Educational Resources Information Center

Mimirinis, Mike

2016-01-01

This study reports the results of a cross-case study analysis of how students' approaches to learning are demonstrated in blended learning environments. It was initially propositioned that approaches to learning as key determinants of the quality of student learning outcomes are demonstrated specifically in how students utilise technology in…

Older Adults can Learn to Learn New Motor Skills

PubMed Central

Seidler, Rachael D.

2007-01-01

Many studies have demonstrated that aging is associated with declines in skill acquisition. In the current study, we tested whether older adults could acquire general, transferable knowledge about skill learning processes. Older adult participants learned five different motor tasks. Two older adult control groups performed the same number of trials, but learned only one task. The experimental group exhibited faster learning than that seen in the control groups. These data demonstrate that older adults can learn to learn new motor skills. PMID:17602760

Social learning by following: an analysis1

PubMed Central

Bullock, Daniel; Neuringer, Allen

1977-01-01

Learning by “following”, probably a common means by which behaviors are socially transmitted from adults to young in many species, was analyzed. Pigeons first learned to eat from a human hand. When the hand then approached an operant key and pecked it, the pigeons followed and quickly learned to do the same, thereby demonstrating social learning. When the hand only led the birds to the area of the key, without demonstrating the key-peck response, the birds learned as rapidly as with a key-peck demonstration. Birds also learned, but less reliably and more slowly, when they could observe the hand's responses but were constrained and unable to follow. “Following” was also shown to engender very rapid learning of a more complex, two-member response chain. PMID:16811970

Verbal implicit sequence learning in persons who stutter and persons with Parkinson's disease.

PubMed

Smits-Bandstra, Sarah; Gracco, Vincent

2013-01-01

The authors investigated the integrity of implicit learning systems in 14 persons with Parkinson's disease (PPD), 14 persons who stutter (PWS), and 14 control participants. In a 120-min session participants completed a verbal serial reaction time task, naming aloud 4 syllables in response to 4 visual stimuli. Unbeknownst to participants, the syllables formed a repeating 8-item sequence. PWS and PPD demonstrated slower reaction times for early but not late learning trials relative to controls reflecting delays but not deficiencies in general learning. PPD also demonstrated less accuracy in general learning relative to controls. All groups demonstrated similar limited explicit sequence knowledge. Both PWS and PPD demonstrated significantly less implicit sequence learning relative to controls, suggesting that stuttering may be associated with compromised functional integrity of the cortico-striato-thalamo-cortical loop.

Effectiveness of Demonstration and Lecture Methods in Learning Concept in Economics among Secondary School Students in Borno State, Nigeria

ERIC Educational Resources Information Center

Muhammad, Amin Umar; Bala, Dauda; Ladu, Kolomi Mutah

2016-01-01

This study investigated the Effectiveness of Demonstration and Lecture Methods in Learning concepts in Economics among Secondary School Students in Borno state, Nigeria. Five objectives: to determine the effectiveness of demonstration method in learning economics concepts among secondary school students in Borno state, determine the effectiveness…

Active Learning in PhysicsTechnology and Research-based Techniques Emphasizing Interactive Lecture Demonstrations

NASA Astrophysics Data System (ADS)

Thornton, Ronald

2010-10-01

Physics education research has shown that learning environments that engage students and allow them to take an active part in their learning can lead to large conceptual gains compared to traditional instruction. Examples of successful curricula and methods include Peer Instruction, Just in Time Teaching, RealTime Physics, Workshop Physics, Scale-Up, and Interactive Lecture Demonstrations (ILDs). An active learning environment is often difficult to achieve in lecture sessions. This presentation will demonstrate the use of sequences of Interactive Lecture Demonstrations (ILDs) that use real experiments often involving real-time data collection and display combined with student interaction to create an active learning environment in large or small lecture classes. Interactive lecture demonstrations will be done in the area of mechanics using real-time motion probes and the Visualizer. A video tape of students involved in interactive lecture demonstrations will be shown. The results of a number of research studies at various institutions (including international) to measure the effectiveness of ILDs and guided inquiry conceptual laboratories will be presented.

Immunization against social fear learning.

PubMed

Golkar, Armita; Olsson, Andreas

2016-06-01

Social fear learning offers an efficient way to transmit information about potential threats; little is known, however, about the learning processes that counteract the social transmission of fear. In three separate experiments, we found that safety information transmitted from another individual (i.e., demonstrator) during preexposure prevented subsequent observational fear learning (Experiments 1-3), and this effect was maintained in a new context involving direct threat confrontation (Experiment 3). This protection from observational fear learning was specific to conditions in which information about both safety and danger was transmitted from the same demonstrator (Experiments 2-3) and was unaffected by increasing the number of the safety demonstrators (Experiment 3). Collectively, these findings demonstrate that observational preexposure can limit social transmission of fear. Future research is needed to better understand the conditions under which such effects generalize across individual demonstrators. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Social learning of an associative foraging task in zebrafish

NASA Astrophysics Data System (ADS)

Zala, Sarah M.; Määttänen, Ilmari

2013-05-01

The zebrafish ( Danio rerio) is increasingly becoming an important model species for studies on the genetic and neural mechanisms controlling behaviour and cognition. Here, we utilized a conditioned place preference (CPP) paradigm to study social learning in zebrafish. We tested whether social interactions with conditioned demonstrators enhance the ability of focal naïve individuals to learn an associative foraging task. We found that the presence of conditioned demonstrators improved focal fish foraging behaviour through the process of social transmission, whereas the presence of inexperienced demonstrators interfered with the learning of the control focal fish. Our results indicate that zebrafish use social learning for finding food and that this CPP paradigm is an efficient assay to study social learning and memory in zebrafish.

How GPs learn.

PubMed

MacLeod, Sheona

2009-07-01

As the requirements for the revalidation of general practitioners (GPs) unfold, there is an increasing emphasis on demonstrating effective continued medical education (CME) based on identified learning needs. This qualitative study aimed to promote understanding of how GPs currently approach their learning. The behaviour of one group of GPs was studied to explore how they assessed and met individual learning needs. The GPs studied showed a pragmatic approach, valuing learning that gave them practical advice and instant access to information for patient-specific problems. The main driver for the GPs' learning was discomfort during their daily work if a possible lack of knowledge or skills was perceived. However, some learning benchmarked current good practice or ensured continued expertise. Learning purely for interest was also described. The GPs in this study all demonstrated a commitment to personal learning, although they were not yet thinking about demonstrating the effectiveness of this for revalidation. The GPs prioritised their learning needs and were beginning to use some objective assessment methods to do this and the GP appraisal process was found to have a mainly positive effect on learning.

Study on Introduction of CO2 Free Energy to Japan with Liquid Hydrogen

NASA Astrophysics Data System (ADS)

Kamiya, Shoji; Nishimura, Motohiko; Harada, Eichi

In Japan, both CO2(Carbon dioxide) emission reduction and energy security are the very important social issues after Fukushima Daiichi accident. On the other hand, FCV (Fuel Cell Vehicle)using hydrogen will be on the market in 2015. Introducing large mass hydrogen energy is being expected as expanding hydrogen applications, or solution to energy issues of Japan.And then,the Japanese government announced the road map for introducing hydrogen energy supply chain in this June,2014. Under these circumstances, imported CO2 free hydrogen will be one of the solutions for energy security and CO2 reduction, if the hydrogen price is affordable. To achieve this, Kawasaki Heavy Industries, Ltd. (KHI) performed a feasibility studyon CO2-free hydrogen energy supply chainfrom Australian brown coal linked with CCS (Carbon dioxide Capture and Storage) to Japan. In the study, hydrogen production systems utilizing brown coal gasificationandLH2 (liquid hydrogen)systems as storing and transporting hydrogen are examined.This paper shows the possibilityof realizingthe CO2 free hydrogen supply chain, the cost breakdown of imported hydrogen cost, its cost competitiveness with conventionalfossil, andLH2systems as key technologies of the hydrogen energy chain.

A comparison of the effects of the dopamine partial agonists aripiprazole and (-)-3-PPP with quinpirole on stimulated dopamine release in the rat striatum: Studies using fast cyclic voltammetry in vitro.

PubMed

O'Connor, John J; Lowry, John P

2012-07-05

The effects of aripiprazole, (-)-(3-hydroxyphenyl)-N-n-propylpiperidine ((-)-3-PPP) and quinpirole on single and multiple pulse stimulated dopamine release were investigated using the technique of fast cyclic voltammetry (FCV) in isolated rat striatal slices. Aripiprazole and (-)-3-PPP had no significant effect on single pulse dopamine release at concentrations from 10nM to 10μM indicating low agonist activity. The compounds failed to potentiate 5 pulse stimulated release of dopamine although inhibitory effects were seen at 10μM for aripiprazole. Both compounds were tested against the concentration-response curve for quinpirole's inhibition of stimulated single pulse dopamine release. Aripiprazole and (-)-3-PPP shifted the concentration-response curve for quinpirole to the right. In each case this was greater than a 100-fold shift for the 10μM test compound. Whilst these results indicate that both compounds show little agonist activity on dopamine release and significant antagonism of the inhibitory effect of quinpirole on dopamine release, whether they are functionally selective dopamine D(2) ligands remains controversial. Copyright © 2012 Elsevier B.V. All rights reserved.

Combined administration in a single injection of a feline multivalent modified live vaccine against FHV, FCV, and FPLV together with a recombinant FeLV vaccine is both safe and efficacious for all four major feline viral pathogens.

PubMed

Kanellos, Theo; Sutton, David J; Salisbury, Claire F; Chalmers, William Stuart K

2008-08-01

Nobivac Tricat, a lyophilised trivalent modified live attenuated vaccine is routinely used to protect cats against three commonly diagnosed feline viral pathogens namely herpesvirus, calicivirus and panleukopenia virus. The recognition of feline leukaemia virus (FeLV) as an important viral pathogen has prompted the development of an efficacious liquid recombinant subunit FeLV vaccine (p45 envelope protein). Lyophilised Tricat vaccine was dissolved in the liquid FeLV vaccine and no detectable deleterious effect on the titre of any of the live virus components was observed after 2h incubation. In vivo studies where the vaccines were mixed in the same syringe prior to inoculation showed no alteration to the safety profile assessed by repeat and overdose studies. Serological comparisons of the modified live viral antibody titres showed no evidence of reduced responses following administration of the mixed products. Challenge studies using pathogenic herpesvirus and FeLV revealed no difference in the degree of clinical protection. This paper shows that neither safety nor efficacy is adversely affected as a result of mixing the two vaccines.

A concise guide to sustainable PEMFCs: recent advances in improving both oxygen reduction catalysts and proton exchange membranes.

PubMed

Scofield, Megan E; Liu, Haiqing; Wong, Stanislaus S

2015-08-21

The rising interest in fuel cell vehicle technology (FCV) has engendered a growing need and realization to develop rational chemical strategies to create highly efficient, durable, and cost-effective fuel cells. Specifically, technical limitations associated with the major constituent components of the basic proton exchange membrane fuel cell (PEMFC), namely the cathode catalyst and the proton exchange membrane (PEM), have proven to be particularly demanding to overcome. Therefore, research trends within the community in recent years have focused on (i) accelerating the sluggish kinetics of the catalyst at the cathode and (ii) minimizing overall Pt content, while simultaneously (a) maximizing activity and durability as well as (b) increasing membrane proton conductivity without causing any concomitant loss in either stability or as a result of damage due to flooding. In this light, as an example, high temperature PEMFCs offer a promising avenue to improve the overall efficiency and marketability of fuel cell technology. In this Critical Review, recent advances in optimizing both cathode materials and PEMs as well as the future and peculiar challenges associated with each of these systems will be discussed.

Social learning across species: horses (Equus caballus) learn from humans by observation.

PubMed

Schuetz, Aurelia; Farmer, Kate; Krueger, Konstanze

2017-05-01

This study examines whether horses can learn by observing humans, given that they identify individual humans and orientate on the focus of human attention. We tested 24 horses aged between 3 and 12. Twelve horses were tested on whether they would learn to open a feeding apparatus by observing a familiar person. The other 12 were controls and received exactly the same experimental procedure, but without a demonstration of how to operate the apparatus. More horses from the group with demonstration (8/12) reached the learning criterion of opening the feeder twenty times consecutively than horses from the control group (2/12), and younger horses seemed to reach the criterion more quickly. Horses not reaching the learning criteria approached the human experimenters more often than those that did. The results demonstrate that horses learn socially across species, in this case from humans.

What Does It Take for an Infant to Learn How to Use a Tool by Observation?

PubMed Central

Fagard, Jacqueline; Rat-Fischer, Lauriane; Esseily, Rana; Somogyi, Eszter; O’Regan, J. K.

2016-01-01

Observational learning is probably one of the most powerful factors determining progress during child development. When learning a new skill, infants rely on their own exploration; but they also frequently benefit from an adult’s verbal support or from demonstration by an adult modeling the action. At what age and under what conditions does adult demonstration really help the infant to learn a novel behavior? In this review, we summarize recently published work we have conducted on the acquisition of tool use during the second year of life. In particular, we consider under what conditions and to what extent seeing a demonstration from an adult advances an infant’s understanding of how to use a tool to obtain an out-of-reach object. Our results show that classic demonstration starts being helpful at 18 months of age. When adults explicitly show their intention prior to demonstration, even 16-month-old infants learn from the demonstration. On the other hand, providing an explicit demonstration (“look at how I do it”) is not very useful before infants are ready to succeed by themselves anyway. In contrast, repeated observations of the required action in a social context, without explicit reference to this action, considerably advances the age of success and the usefulness of providing a demonstration. We also show that the effect of demonstration can be enhanced if the demonstration makes the baby laugh. Taken together, the results from this series of studies on observational learning of tool use in infants suggest, first, that when observing a demonstration, infants do not know what to pay attention to: demonstration must be accompanied by rich social cues to be effective; second, infants’ attention is inhibited rather than enhanced by an explicit demand of “look at what I do”; and finally a humorous situation considerably helps infants understand the demonstration. PMID:26973565

What Does It Take for an Infant to Learn How to Use a Tool by Observation?

PubMed

Fagard, Jacqueline; Rat-Fischer, Lauriane; Esseily, Rana; Somogyi, Eszter; O'Regan, J K

2016-01-01

Observational learning is probably one of the most powerful factors determining progress during child development. When learning a new skill, infants rely on their own exploration; but they also frequently benefit from an adult's verbal support or from demonstration by an adult modeling the action. At what age and under what conditions does adult demonstration really help the infant to learn a novel behavior? In this review, we summarize recently published work we have conducted on the acquisition of tool use during the second year of life. In particular, we consider under what conditions and to what extent seeing a demonstration from an adult advances an infant's understanding of how to use a tool to obtain an out-of-reach object. Our results show that classic demonstration starts being helpful at 18 months of age. When adults explicitly show their intention prior to demonstration, even 16-month-old infants learn from the demonstration. On the other hand, providing an explicit demonstration ("look at how I do it") is not very useful before infants are ready to succeed by themselves anyway. In contrast, repeated observations of the required action in a social context, without explicit reference to this action, considerably advances the age of success and the usefulness of providing a demonstration. We also show that the effect of demonstration can be enhanced if the demonstration makes the baby laugh. Taken together, the results from this series of studies on observational learning of tool use in infants suggest, first, that when observing a demonstration, infants do not know what to pay attention to: demonstration must be accompanied by rich social cues to be effective; second, infants' attention is inhibited rather than enhanced by an explicit demand of "look at what I do"; and finally a humorous situation considerably helps infants understand the demonstration.

Developing Noticing of Reasoning through Demonstration Lessons

ERIC Educational Resources Information Center

Bragg, Leicha A.; Vale, Colleen

2014-01-01

Observation of fellow educators conducting demonstration lessons is one avenue for teachers to develop sensitivity to noticing students' reasoning. We examined teachers' noticing of children's learning behaviours in one demonstration lesson of the "Mathematical Reasoning Professional Learning Research Program" (MRPLRP). The observations…

An fMRI investigation of the fronto-striatal learning system in women who exhibit eating disorder behaviors

PubMed Central

Celone, Kim A.; Thompson-Brenner, Heather; Ross, Robert S.; Pratt, Elizabeth M.; Stern, Chantal E.

2013-01-01

In the present study, we sought to examine whether the fronto-striatal learning system, which has been implicated in bulimia nervosa, would demonstrate altered BOLD activity during probabilistic category learning in women who met subthreshold criteria for bulimia nervosa (Sub-BN). Sub-BN, which falls within the clinical category of Eating Disorder Not Otherwise Specified (EDNOS), is comprised of individuals who demonstrate recurrent binge eating, efforts to minimize their caloric intake and caloric retention, and elevated levels of concern about shape, weight, and/or eating, but just fail to meet the diagnostic threshold for bulimia nervosa (BN). fMRI data were collected from eighteen women with subthreshold-BN (Sub-BN) and nineteen healthy control women group-matched for age, education and body mass index (MC) during the weather prediction task. Sub-BN participants demonstrated increased caudate nucleus and dorsolateral prefrontal cortex (DLPFC) activation during the learning of probabilistic categories. Though the two subject groups did not differ in behavioral performance, over the course of learning, Sub-BN participants showed a dynamic pattern of brain activity differences when compared to matched control participants. Regions implicated in episodic memory, including the medial temporal lobe (MTL), retrosplenial cortex, middle frontal gyrus, and anterior and posterior cingulate cortex showed decreased activity in the Sub-BN participants compared to MCs during early learning which was followed by increased involvement of the DLPFC during later learning. These findings demonstrate that women with Sub-BN demonstrate differences in fronto-striatal learning system activity, as well as a distinct functional pattern between fronto-striatal and MTL learning systems during the course of implicit probabilistic category learning. PMID:21419229

Summer Learning Programs Yield Key Lessons for Districts and Policymakers

ERIC Educational Resources Information Center

Augustine, Catherine H.; McCombs, Jennifer Sloan

2015-01-01

The Wallace Foundation is funding a multiyear demonstration project to determine whether voluntary, district summer learning programs can stem summer learning loss for low-income students. Six districts--Boston, Cincinnati, Dallas, Duval County (Florida), Pittsburgh, and Rochester, New York--were selected for the demonstration project and…

The evolutionary basis of human social learning

PubMed Central

Morgan, T. J. H.; Rendell, L. E.; Ehn, M.; Hoppitt, W.; Laland, K. N.

2012-01-01

Humans are characterized by an extreme dependence on culturally transmitted information. Such dependence requires the complex integration of social and asocial information to generate effective learning and decision making. Recent formal theory predicts that natural selection should favour adaptive learning strategies, but relevant empirical work is scarce and rarely examines multiple strategies or tasks. We tested nine hypotheses derived from theoretical models, running a series of experiments investigating factors affecting when and how humans use social information, and whether such behaviour is adaptive, across several computer-based tasks. The number of demonstrators, consensus among demonstrators, confidence of subjects, task difficulty, number of sessions, cost of asocial learning, subject performance and demonstrator performance all influenced subjects' use of social information, and did so adaptively. Our analysis provides strong support for the hypothesis that human social learning is regulated by adaptive learning rules. PMID:21795267

The evolutionary basis of human social learning.

PubMed

Morgan, T J H; Rendell, L E; Ehn, M; Hoppitt, W; Laland, K N

2012-02-22

Humans are characterized by an extreme dependence on culturally transmitted information. Such dependence requires the complex integration of social and asocial information to generate effective learning and decision making. Recent formal theory predicts that natural selection should favour adaptive learning strategies, but relevant empirical work is scarce and rarely examines multiple strategies or tasks. We tested nine hypotheses derived from theoretical models, running a series of experiments investigating factors affecting when and how humans use social information, and whether such behaviour is adaptive, across several computer-based tasks. The number of demonstrators, consensus among demonstrators, confidence of subjects, task difficulty, number of sessions, cost of asocial learning, subject performance and demonstrator performance all influenced subjects' use of social information, and did so adaptively. Our analysis provides strong support for the hypothesis that human social learning is regulated by adaptive learning rules.

Visible spatial contiguity of social information and reward affects social learning in brown capuchins (Sapajus apella) and children (Homo sapiens).

PubMed

Wood, Lara A; Whiten, Andrew

2017-11-01

Animal social learning is typically studied experimentally by the presentation of artificial foraging tasks. Although productive, results are often variable even for the same species. We present and test the hypothesis that one cause of variation is that spatial distance between rewards and the means of reward release causes conflicts for participants' attentional focus. We investigated whether spatial contiguity between a visible reward and the means of release would affect behavioral responses that evidence social learning, testing 21 brown capuchins ( Sapajus apella ), a much-studied species with variant evidence for social learning, and one hundred eighty 2- to 4-year-old human children ( Homo sapiens ), a benchmark species known for a strong social learning disposition. Participants were presented with a novel transparent apparatus where a reward was either proximal or distal to a demonstrated means of releasing it. A distal reward location decreased attention toward the location of the demonstration and impaired subsequent success in gaining rewards. Generally, the capuchins produced the alternative method to that demonstrated, whereas children copied the method demonstrated, although a distal reward location reduced copying in younger children. We conclude that some design features in common social learning tasks may significantly degrade the evidence for social learning. We have demonstrated this for 2 different primates but suggest that it is a significant factor to control for in social learning research across all taxa. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Non-linguistic learning in aphasia: Effects of training method and stimulus characteristics

PubMed Central

Vallila-Rohter, Sofia; Kiran, Swathi

2013-01-01

Purpose The purpose of the current study was to explore non-linguistic learning ability in patients with aphasia, examining the impact of stimulus typicality and feedback on success with learning. Method Eighteen patients with aphasia and eight healthy controls participated in this study. All participants completed four computerized, non-linguistic category-learning tasks. We probed learning ability under two methods of instruction: feedback-based (FB) and paired-associate (PA). We also examined the impact of task complexity on learning ability, comparing two stimulus conditions: typical (Typ) and atypical (Atyp). Performance was compared between groups and across conditions. Results Results demonstrated that healthy controls were able to successfully learn categories under all conditions. For our patients with aphasia, two patterns of performance arose. One subgroup of patients was able to maintain learning across task manipulations and conditions. The other subgroup of patients demonstrated a sensitivity to task complexity, learning successfully only in the typical training conditions. Conclusions Results support the hypothesis that impairments of general learning are present in aphasia. Some patients demonstrated the ability to extract category information under complex training conditions, while others learned only under conditions that were simplified and emphasized salient category features. Overall, the typical training condition facilitated learning for all participants. Findings have implications for therapy, which are discussed. PMID:23695914

Learning Skills Profiles of master's students in nursing administration: assessing the impact of problem-based learning.

PubMed

Baker, Constance M; McDaniel, Anna M; Pesut, Daniel J; Fisher, Mary L

2007-01-01

Attempts to compare graduate student performances before and after introducing new curricula are rare; yet faculties need outcome measures to justify program costs and demonstrate effectiveness. Boyatzis and Kolb's Learning Skills Profile is used to assess the outcomes of a problem-based learning MSN program. Increases were demonstrated among all 12 learning skills; statistically significant increases were found in eight of the personal learning skills and six of the job skill demands. Comparisons are made between scores of students in the MSN program and scores of master's students in business administration.

H2Oh!: Classroom demonstrations and activities for improving student learning of water concepts

NASA Astrophysics Data System (ADS)

Chan-Hilton, A.; Neupauer, R. M.; Burian, S. J.; Lauer, J. W.; Mathisen, P. P.; Mays, D. C.; Olson, M. S.; Pomeroy, C. A.; Ruddell, B. L.; Sciortino, A.

2012-12-01

Research has shown that the use of demonstrations and hands-on activities in the classroom enhances student learning. Students learn more and enjoy classes more when visual and active learning are incorporated into the lecture. Most college-aged students prefer visual modes of learning, while most instruction is conducted in a lecture, or auditory, format. The use of classroom demonstrations provides opportunities for incorporating visual and active learning into the classroom environment. However, while most instructors acknowledge the benefits of these teaching methods, they typically do not have the time and resources to develop and test such activities and to develop plans to incorporate them into their lectures. Members of the Excellence in Water Resources Education Task Committee of the Environmental and Water Resources Institute (EWRI) of the American Society of Civil Engineers (ASCE) have produced a publication that contains a collection of activities aimed to foster excellence in water resources and hydrology education and improve student learning of principles. The book contains forty-five demonstrations and activities that can be used in water-related classes with topics in fluid mechanics, hydraulics, surface water hydrology, groundwater hydrology, and water quality. We present examples of these activities, including topics such as conservation of momentum, buoyancy, Bernoulli's principle, drag force, pipe flow, watershed delineation, reservoir networks, head distribution in aquifers, and molecular diffusion in a porous medium. Unlike full laboratory exercises, these brief demonstrations and activities (most of which take less than fifteen minutes) can be easily incorporated into classroom lectures. For each demonstration, guidance for preparing and conducting the activity, along with a brief overview of the principles that are demonstrated, is provided. The target audience of the activities is undergraduate students, although the activities also may be used in K-12 and graduate classes.

Do semantic contextual cues facilitate transfer learning from video in toddlers?

PubMed Central

Zimmermann, Laura; Moser, Alecia; Grenell, Amanda; Dickerson, Kelly; Yao, Qianwen; Gerhardstein, Peter; Barr, Rachel

2015-01-01

Young children typically demonstrate a transfer deficit, learning less from video than live presentations. Semantically meaningful context has been demonstrated to enhance learning in young children. We examined the effect of a semantically meaningful context on toddlers’ imitation performance. Two- and 2.5-year-olds participated in a puzzle imitation task to examine learning from either a live or televised model. The model demonstrated how to assemble a three-piece puzzle to make a fish or a boat, with the puzzle demonstration occurring against a semantically meaningful background context (ocean) or a yellow background (no context). Participants in the video condition performed significantly worse than participants in the live condition, demonstrating the typical transfer deficit effect. While the context helped improve overall levels of imitation, especially for the boat puzzle, only individual differences in the ability to self-generate a stimulus label were associated with a reduction in the transfer deficit. PMID:26029131

Do semantic contextual cues facilitate transfer learning from video in toddlers?

PubMed

Zimmermann, Laura; Moser, Alecia; Grenell, Amanda; Dickerson, Kelly; Yao, Qianwen; Gerhardstein, Peter; Barr, Rachel

2015-01-01

Young children typically demonstrate a transfer deficit, learning less from video than live presentations. Semantically meaningful context has been demonstrated to enhance learning in young children. We examined the effect of a semantically meaningful context on toddlers' imitation performance. Two- and 2.5-year-olds participated in a puzzle imitation task to examine learning from either a live or televised model. The model demonstrated how to assemble a three-piece puzzle to make a fish or a boat, with the puzzle demonstration occurring against a semantically meaningful background context (ocean) or a yellow background (no context). Participants in the video condition performed significantly worse than participants in the live condition, demonstrating the typical transfer deficit effect. While the context helped improve overall levels of imitation, especially for the boat puzzle, only individual differences in the ability to self-generate a stimulus label were associated with a reduction in the transfer deficit.

Location, Location, Location! Demonstrating the Mnemonic Benefit of the Method of Loci

ERIC Educational Resources Information Center

McCabe, Jennifer A.

2015-01-01

Classroom demonstrations of empirically supported learning and memory strategies have the potential to boost students' knowledge about their own memory and convince them to change the way they approach memory tasks in and beyond the classroom. Students in a "Human Learning and Memory" course learned about the "Method of Loci"…

Neurological Processes and Reading Pathology: Knowing About Children and Reading Dysfunction.

ERIC Educational Resources Information Center

Roberts, David Harrill

For many years dyslexia has been incorrectly applied to those who have demonstrated difficulty in learning to read. Given the proper guidance and opportunities for becoming sensitive to demonstrations of the workings of language and engaging their minds in learning, many students will overcome their so-called learning disabilities. However, there…

Evaluating a "Second Life" Problem-Based Learning (PBL) Demonstrator Project: What Can We Learn?

ERIC Educational Resources Information Center

Beaumont, Chris; Savin-Baden, Maggi; Conradi, Emily; Poulton, Terry

2014-01-01

This article reports the findings of a demonstrator project to evaluate how effectively Immersive Virtual Worlds (IVWs) could support problem-based learning. The project designed, created and evaluated eight scenarios within "Second Life" (SL) for undergraduate courses in health care management and paramedic training. Evaluation was…

Personality predicts the propensity for social learning in a wild primate

PubMed Central

Marshall, Harry H.; Heinsohn, Robert; Cowlishaw, Guy

2014-01-01

Social learning can play a critical role in the reproduction and survival of social animals. Individual differences in the propensity for social learning are therefore likely to have important fitness consequences. We asked whether personality might underpin such individual variation in a wild population of chacma baboons (Papio ursinus). We used two field experiments in which individuals had the opportunity to learn how to solve a task from an experienced conspecific demonstrator: exploitation of a novel food and a hidden item of known food. We investigated whether the (1) time spent watching a demonstrator and (2) changes in task-solving behaviour after watching a demonstrator were related to personality. We found that both boldness and anxiety influenced individual performance in social learning. Specifically, bolder and more anxious animals were more likely to show a greater improvement in task solving after watching a demonstrator. In addition, there was also evidence that the acquisition of social information was not always correlated with its use. These findings present new insights into the costs and benefits of different personality types, and have important implications for the evolution of social learning. PMID:24688861

Effect of Vicarious Fear Learning on Children’s Heart Rate Responses and Attentional Bias for Novel Animals

PubMed Central

2014-01-01

Research with children has shown that vicarious learning can result in changes to 2 of Lang’s (1968) 3 anxiety response systems: subjective report and behavioral avoidance. The current study extended this research by exploring the effect of vicarious learning on physiological responses (Lang’s final response system) and attentional bias. The study used Askew and Field’s (2007) vicarious learning procedure and demonstrated fear-related increases in children’s cognitive, behavioral, and physiological responses. Cognitive and behavioral changes were retested 1 week and 1 month later, and remained elevated. In addition, a visual search task demonstrated that fear-related vicarious learning creates an attentional bias for novel animals, which is moderated by increases in fear beliefs during learning. The findings demonstrate that vicarious learning leads to lasting changes in all 3 of Lang’s anxiety response systems and is sufficient to create attentional bias to threat in children. PMID:25151521

Neural learning circuits utilizing nano-crystalline silicon transistors and memristors.

PubMed

Cantley, Kurtis D; Subramaniam, Anand; Stiegler, Harvey J; Chapman, Richard A; Vogel, Eric M

2012-04-01

Properties of neural circuits are demonstrated via SPICE simulations and their applications are discussed. The neuron and synapse subcircuits include ambipolar nano-crystalline silicon transistor and memristor device models based on measured data. Neuron circuit characteristics and the Hebbian synaptic learning rule are shown to be similar to biology. Changes in the average firing rate learning rule depending on various circuit parameters are also presented. The subcircuits are then connected into larger neural networks that demonstrate fundamental properties including associative learning and pulse coincidence detection. Learned extraction of a fundamental frequency component from noisy inputs is demonstrated. It is then shown that if the fundamental sinusoid of one neuron input is out of phase with the rest, its synaptic connection changes differently than the others. Such behavior indicates that the system can learn to detect which signals are important in the general population, and that there is a spike-timing-dependent component of the learning mechanism. Finally, future circuit design and considerations are discussed, including requirements for the memristive device.

Social learning in nest-building birds watching live-streaming video demonstrators.

PubMed

Guillette, Lauren M; Healy, Susan D

2018-02-13

Determining the role that social learning plays in construction behaviours, such as nest building or tool manufacture, could be improved if more experimental control could be gained over the exact public information that is provided by the demonstrator, to the observing individual. Using video playback allows the experimenter to choose what information is provided, but will only be useful in determining the role of social learning if observers attend to, and learn from, videos in a manner that is similar to live demonstration. The goal of the current experiment was to test whether live-streamed video presentations of nest building by zebra finches Taeniopygia guttata would lead observers to copy the material choice demonstrated to them. Here, males that had not previously built a nest were given an initial preference test between materials of two colours. Those observers then watched live-stream footage of a familiar demonstrator building a nest with material of the colour that the observer did not prefer. After this experience, observers were given the chance to build a nest with materials of the two colours. Although two-thirds of the observer males preferred material of the demonstrated colour after viewing the demonstrator build a nest with material of that colour more than they had previously, their preference for the demonstrated material was not as strong as that of observers that had viewed live demonstrator builders in a previous experiment. Our results suggest researchers should proceed with caution before using video demonstration in tests of social learning. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Computer-based learning in neuroanatomy: A longitudinal study of learning, transfer, and retention

NASA Astrophysics Data System (ADS)

Chariker, Julia H.

A longitudinal experiment was conducted to explore computer-based learning of neuroanatomy. Using a realistic 3D graphical model of neuroanatomy, and sections derived from the model, exploratory graphical tools were integrated into interactive computer programs so as to allow adaptive exploration. 72 participants learned either sectional anatomy alone or learned whole anatomy followed by sectional anatomy. Sectional anatomy was explored either in perceptually continuous animation or discretely, as in the use of an anatomical atlas. Learning was measured longitudinally to a high performance criterion. After learning, transfer to biomedical images and long-term retention was tested. Learning whole anatomy prior to learning sectional anatomy led to a more efficient learning experience. Learners demonstrated high levels of transfer from whole anatomy to sectional anatomy and from sectional anatomy to complex biomedical images. All learning groups demonstrated high levels of retention at 2--3 weeks.

Learning through a portfolio of carbon capture and storage demonstration projects

NASA Astrophysics Data System (ADS)

Reiner, David M.

2016-01-01

Carbon dioxide capture and storage (CCS) technology is considered by many to be an essential route to meet climate mitigation targets in the power and industrial sectors. Deploying CCS technologies globally will first require a portfolio of large-scale demonstration projects. These first projects should assist learning by diversity, learning by replication, de-risking the technologies and developing viable business models. From 2005 to 2009, optimism about the pace of CCS rollout led to mutually independent efforts in the European Union, North America and Australia to assemble portfolios of projects. Since 2009, only a few of these many project proposals remain viable, but the initial rationales for demonstration have not been revisited in the face of changing circumstances. Here I argue that learning is now both more difficult and more important given the slow pace of deployment. Developing a more coordinated global portfolio will facilitate learning across projects and may determine whether CCS ever emerges from the demonstration phase.

From Learning Organization to Learning Community: Sustainability through Lifelong Learning

ERIC Educational Resources Information Center

Kearney, Judith; Zuber-Skerritt, Ortrun

2012-01-01

Purpose: This paper aims to: extend the concept of "The learning organization" to "The learning community," especially disadvantaged communities; demonstrate how leaders in a migrant community can achieve positive change at the personal, professional, team and community learning levels through participatory action learning and…

Responding To School Walkout Demonstrations. Lessons Learned From School Crises and Emergencies, Volume 3, Issue 1, 2008

ERIC Educational Resources Information Center

US Department of Education, 2008

2008-01-01

"Lessons Learned" is a series of publications that are a brief recounting of actual school emergencies and crises. This "Lessons Learned" issue examines the incidence of student walkout demonstrations and the various ways in which administrators, school staff, law enforcement, and the community at large can help keep youths…

Distance Learning Engineering Students Languish under Project-Based Learning, but Thrive in Case Studies and Practical Workshops

ERIC Educational Resources Information Center

Swart, Arthur James

2016-01-01

The International Engineering Alliance lists 12 important graduate attributes that students must demonstrate during their higher educational career. One of these important graduate attributes is the ability to solve problems, which can be demonstrated by the use of project-based learning, case studies, and practical workshops. The purpose of this…

The Relevance of the Nature of Learned Associations for the Differentiation of Human Memory Systems

ERIC Educational Resources Information Center

Rose, Michael; Haider, Hilde; Weiller, Cornelius; Buchel, Christian

2004-01-01

In a previous functional magnetic resonance imaging (fMRI) study we demonstrated an involvement of the medial temporal lobe (MTL) during an implicit learning task. We concluded that the MTL was engaged because of the complex contingencies that were implicitly learned. In addition, the basal ganglia demonstrated effects of a paralleled…

"Ready To Learn" Transmedia Demonstration Station Study: A Report to the CPB-PBS "Ready to Learn Initiative"

ERIC Educational Resources Information Center

Pasnik, Shelley; Llorente, Carlin

2012-01-01

The 2012 Transmedia Demonstration Stations program study is part of the multiyear CPB-PBS "Ready To Learn" summative evaluation initiative by Education Development Center, Inc., (EDC) and SRI International (SRI). Through a series of related studies, the authors are documenting, and, whenever possible, measuring the impact of PBS KIDS…

A Joyful Classroom Learning System with Robot Learning Companion for Children to Learn Mathematics Multiplication

ERIC Educational Resources Information Center

Wei, Chun-Wang; Hung, I-Chun; Lee, Ling; Chen, Nian-Shing

2011-01-01

This research demonstrates the design of a Joyful Classroom Learning System (JCLS) with flexible, mobile and joyful features. The theoretical foundations of this research include the experiential learning theory, constructivist learning theory and joyful learning. The developed JCLS consists of the robot learning companion (RLC), sensing input…

Web Cast on Arsenic Demonstration Program: Lessons Learned

EPA Science Inventory

Web cast presentation covered 10 Lessons Learned items selected from the Arsenic Demonstration Program with supporting information. The major items discussed include system design and performance items and the cost of the technologies.

Attempting to "Increase Intake from the Input": Attention and Word Learning in Children with Autism

ERIC Educational Resources Information Center

Tenenbaum, Elena J.; Amso, Dima; Righi, Giulia; Sheinkopf, Stephen J.

2017-01-01

Previous work has demonstrated that social attention is related to early language abilities. We explored whether we can facilitate word learning among children with autism by directing attention to areas of the scene that have been demonstrated as relevant for successful word learning. We tracked eye movements to faces and objects while children…

Human-Machine Collaborative Optimization via Apprenticeship Scheduling

DTIC Science & Technology

2016-09-09

prenticeship Scheduling (COVAS), which performs ma- chine learning using human expert demonstration, in conjunction with optimization, to automatically and ef...ficiently produce optimal solutions to challenging real- world scheduling problems. COVAS first learns a policy from human scheduling demonstration via...apprentice- ship learning , then uses this initial solution to provide a tight bound on the value of the optimal solution, thereby substantially

Creative Writing and Learning in a Conceptual Astrophysics Course

NASA Astrophysics Data System (ADS)

Berenson, R.

2012-08-01

Creative writing assignments in a conceptual astrophysics course for liberal arts students can reduce student anxiety. This study demonstrates that such assignments also can aid learning as demonstrated by significantly improved performance on exams.

Learning community health nursing concepts from clinical experience.

PubMed

Lasater, Kathie; Luce, Linda; Volpin, Miriam; Terwilliger, Allison; Wild, Jackson

2007-01-01

Clinical faculty often struggle to design competency demonstrations that promote quality learning experiences. A nursing program in Oregon combined mental health and community health nursing practica and required well-planned, integrated competency demonstrations. This requirement became the impetus for students to promote the health of clients and learn clinical concepts that are difficult to experience in a typical term. Faculty coached students to make a significant contribution that would last beyond their clinical practica. A case study in competency demonstration design is described, and implications for curriculum development are presented.

Age-related changes in learning across early childhood: a new imitation task.

PubMed

Dickerson, Kelly; Gerhardstein, Peter; Zack, Elizabeth; Barr, Rachel

2013-11-01

Imitation plays a critical role in social and cognitive development, but the social learning mechanisms contributing to the development of imitation are not well understood. We developed a new imitation task designed to examine social learning mechanisms across the early childhood period. The new task involves assembly of abstract-shaped puzzle pieces in an arbitrary sequence on a magnet board. Additionally, we introduce a new scoring system that extends traditional goal-directed imitation scoring to include measures of both children's success at copying gestures (sliding the puzzle pieces) and goals (connecting the puzzle pieces). In Experiment 1, we demonstrated an age-invariant baseline from 1.5 to 3.5 years of age, accompanied by age-related changes in success at copying goals and gestures from a live demonstrator. In Experiment 2, we applied our new task to learning following a video demonstration. Imitation performance in the video demonstration group lagged behind that of the live demonstration group, showing a protracted video deficit effect. Across both experiments, children were more likely to copy gestures at earlier ages, suggesting mimicry, and only later copy both goals and gestures, suggesting imitation. Taken together, the findings suggest that different social learning strategies may predominate in imitation learning dependent upon the degree of object affordance, task novelty, and task complexity. © 2012 Wiley Periodicals, Inc.

On the Conditioning of Machine-Learning-Assisted Turbulence Modeling

NASA Astrophysics Data System (ADS)

Wu, Jinlong; Sun, Rui; Wang, Qiqi; Xiao, Heng

2017-11-01

Recently, several researchers have demonstrated that machine learning techniques can be used to improve the RANS modeled Reynolds stress by training on available database of high fidelity simulations. However, obtaining improved mean velocity field remains an unsolved challenge, restricting the predictive capability of current machine-learning-assisted turbulence modeling approaches. In this work we define a condition number to evaluate the model conditioning of data-driven turbulence modeling approaches, and propose a stability-oriented machine learning framework to model Reynolds stress. Two canonical flows, the flow in a square duct and the flow over periodic hills, are investigated to demonstrate the predictive capability of the proposed framework. The satisfactory prediction performance of mean velocity field for both flows demonstrates the predictive capability of the proposed framework for machine-learning-assisted turbulence modeling. With showing the capability of improving the prediction of mean flow field, the proposed stability-oriented machine learning framework bridges the gap between the existing machine-learning-assisted turbulence modeling approaches and the demand of predictive capability of turbulence models in real applications.

Involvement in Learning Revisited: Lessons We Have Learned.

ERIC Educational Resources Information Center

Astin, Alexander W.

1996-01-01

Discusses interconnections between the following two national reports: (1) Involvement in Learning; and (2) The Student Learning Imperative. Reviews recent research on student development in order to demonstrate how student affairs professionals can use this information to enhance learning. (SNR)

The effectiveness of humane teaching methods in veterinary education.

PubMed

Knight, Andrew

2007-01-01

Animal use resulting in harm or death has historically played an integral role in veterinary education, in disciplines such as surgery, physiology, biochemistry, anatomy, pharmacology, and parasitology. However, many non-harmful alternatives now exist, including computer simulations, high quality videos, ''ethically-sourced cadavers'' such as from animals euthanased for medical reasons, preserved specimens, models and surgical simulators, non-invasive self-experimentation, and supervised clinical experiences. Veterinary students seeking to use such methods often face strong opposition from faculty members, who usually cite concerns about their teaching efficacy. Consequently, studies of veterinary students were reviewed comparing learning outcomes generated by non-harmful teaching methods with those achieved by harmful animal use. Of eleven published from 1989 to 2006, nine assessed surgical training--historically the discipline involving greatest harmful animal use. 45.5% (5/11) demonstrated superior learning outcomes using more humane alternatives. Another 45.5% (5/11) demonstrated equivalent learning outcomes, and 9.1% (1/11) demonstrated inferior learning outcomes. Twenty one studies of non-veterinary students in related academic disciplines were also published from 1968 to 2004. 38.1% (8/21) demonstrated superior, 52.4% (11/21) demonstrated equivalent, and 9.5% (2/21) demonstrated inferior learning outcomes using humane alternatives. Twenty nine papers in which comparison with harmful animal use did not occur illustrated additional benefits of humane teaching methods in veterinary education, including: time and cost savings, enhanced potential for customisation and repeatability of the learning exercise, increased student confidence and satisfaction, increased compliance with animal use legislation, elimination of objections to the use of purpose-killed animals, and integration of clinical perspectives and ethics early in the curriculum. The evidence demonstrates that veterinary educators can best serve their students and animals, while minimising financial and time burdens, by introducing well-designed teaching methods not reliant on harmful animal use.

The Structural Underpinnings of Policy Learning: A Classroom Policy Simulation

NASA Astrophysics Data System (ADS)

Bird, Stephen

This paper investigates the relationship between the centrality of individual actors in a social network structure and their policy learning performance. In a dynamic comparable to real-world policy networks, results from a classroom simulation demonstrate a strong relationship between centrality in social learning networks and grade performance. Previous research indicates that social network centrality should have a positive effect on learning in other contexts and this link is tested in a policy learning context. Second, the distinction between collaborative learning versus information diffusion processes in policy learning is examined. Third, frequency of interaction is analyzed to determine whether consistent, frequent tics have a greater impact on the learning process. Finally, the data arc analyzed to determine if the benefits of centrality have limitations or thresholds when benefits no longer accrue. These results demonstrate the importance of network structure, and support a collaborative conceptualization of the policy learning process.

Unsupervised Transfer Learning via Multi-Scale Convolutional Sparse Coding for Biomedical Applications

PubMed Central

Chang, Hang; Han, Ju; Zhong, Cheng; Snijders, Antoine M.; Mao, Jian-Hua

2017-01-01

The capabilities of (I) learning transferable knowledge across domains; and (II) fine-tuning the pre-learned base knowledge towards tasks with considerably smaller data scale are extremely important. Many of the existing transfer learning techniques are supervised approaches, among which deep learning has the demonstrated power of learning domain transferrable knowledge with large scale network trained on massive amounts of labeled data. However, in many biomedical tasks, both the data and the corresponding label can be very limited, where the unsupervised transfer learning capability is urgently needed. In this paper, we proposed a novel multi-scale convolutional sparse coding (MSCSC) method, that (I) automatically learns filter banks at different scales in a joint fashion with enforced scale-specificity of learned patterns; and (II) provides an unsupervised solution for learning transferable base knowledge and fine-tuning it towards target tasks. Extensive experimental evaluation of MSCSC demonstrates the effectiveness of the proposed MSCSC in both regular and transfer learning tasks in various biomedical domains. PMID:28129148

Learning to teach optics through experiments and demonstrations

NASA Astrophysics Data System (ADS)

Lancis, Jesús; Fernández-Alonso, Mercedes; Martínez-León, Lluis; Tajahuerce-Romera, Enrique; Mínguez-Vega, Gladis

2014-07-01

We have applied an active methodology to pre-service teacher training courses and to active teacher workshops on Optics. As a practical resource, a set of demonstrations has been used to learn how to perform classroom demonstrations. The set includes experiments about polarization and birefringence, optical information transmission, diffraction, fluorescence or scattering. It had been prepared for Science popularization activities and has been employed in several settings with a variety of audiences. In the teacher training sessions, simple but clarifying experiments have been performed by all the participants. Moreover, in these workshops, devices or basic set-ups, like the ones included in our demonstration set, have been built. The practical approach has allowed the enthusiastic sharing of teaching and learning experiences among the workshop participants. We believe that such an active orientation in teacher training courses promotes the active and collaborative teaching and learning of Optics in different levels of Education.

Descriptive epidemiology of upper respiratory disease and associated risk factors in cats in an animal shelter in coastal western Canada

PubMed Central

Gourkow, Nadine; Lawson, James H.; Hamon, Sara C.; Phillips, Clive J.C.

2013-01-01

We examined 250 cats at an animal shelter in the coastal temperate region of Canada to determine whether age, source, gender, and sterilization status influenced risk of shedding at intake, transmission of infection, and development of clinical upper respiratory disease (URD). On admission, 28% of the cats were positive for 1 or more infectious agent related to URD; 21% were carriers of Mycoplasma felis and < 3% were carriers of feline calicivirus (FCV), feline herpesvirus-1 (FHV-1) or Bordetella bronchiseptica. Chlamydophila felis and H1N1 influenza virus were not detected. Carrier status was not affected by source, gender, sterilization status, or age (P > 0.05). Viral and bacterial shedding increased by 9% and 11%, respectively, over 3 sampling times (days 1, 4, and 10). Over 40 days after admission, the cumulative probability of developing URD was 2.2 times greater for stray than owner-surrendered cats (P = 0.02) and 0.5 times as great for neutered cats as for intact cats (P = 0.03). Cats that were shedding at intake were 2.6 times more likely to develop URD than were non-carriers (P < 0.002). Cats with FHV-1 and B. bronchiseptica infections were most at risk compared with non-shedding cats (P < 0.01). PMID:23904635

Molecular detection of viral agents in free-ranging and captive neotropical felids in Brazil.

PubMed

Furtado, Mariana M; Taniwaki, Sueli A; de Barros, Iracema N; Brandão, Paulo E; Catão-Dias, José L; Cavalcanti, Sandra; Cullen, Laury; Filoni, Claudia; Jácomo, Anah T de Almeida; Jorge, Rodrigo S P; Silva, Nairléia Dos Santos; Silveira, Leandro; Ferreira Neto, José S

2017-09-01

We describe molecular testing for felid alphaherpesvirus 1 (FHV-1), carnivore protoparvovirus 1 (CPPV-1), feline calicivirus (FCV), alphacoronavirus 1 (feline coronavirus [FCoV]), feline leukemia virus (FeLV), feline immunodeficiency virus (FIV), and canine distemper virus (CDV) in whole blood samples of 109 free-ranging and 68 captive neotropical felids from Brazil. Samples from 2 jaguars ( Panthera onca) and 1 oncilla ( Leopardus tigrinus) were positive for FHV-1; 2 jaguars, 1 puma ( Puma concolor), and 1 jaguarundi ( Herpairulus yagouaroundi) tested positive for CPPV-1; and 1 puma was positive for FIV. Based on comparison of 103 nucleotides of the UL24-UL25 gene, the FHV-1 sequences were 99-100% similar to the FHV-1 strain of domestic cats. Nucleotide sequences of CPPV-1 were closely related to sequences detected in other wild carnivores, comparing 294 nucleotides of the VP1 gene. The FIV nucleotide sequence detected in the free-ranging puma, based on comparison of 444 nucleotides of the pol gene, grouped with other lentiviruses described in pumas, and had 82.4% identity with a free-ranging puma from Yellowstone Park and 79.5% with a captive puma from Brazil. Our data document the circulation of FHV-1, CPPV-1, and FIV in neotropical felids in Brazil.

Protective role of Kv7 channels in oxygen and glucose deprivation-induced damage in rat caudate brain slices

PubMed Central

Barrese, Vincenzo; Taglialatela, Maurizio; Greenwood, Iain A; Davidson, Colin

2015-01-01

Ischemic stroke can cause striatal dopamine efflux that contributes to cell death. Since Kv7 potassium channels regulate dopamine release, we investigated the effects of their pharmacological modulation on dopamine efflux, measured by fast cyclic voltammetry (FCV), and neurotoxicity, in Wistar rat caudate brain slices undergoing oxygen and glucose deprivation (OGD). The Kv7 activators retigabine and ICA27243 delayed the onset, and decreased the peak level of dopamine efflux induced by OGD; and also decreased OGD-induced damage measured by 2,3,5-triphenyltetrazolium chloride (TTC) staining. Retigabine also reduced OGD-induced necrotic cell death evaluated by lactate dehydrogenase activity assay. The Kv7 blocker linopirdine increased OGD-evoked dopamine efflux and OGD-induced damage, and attenuated the effects of retigabine. Quantitative-PCR experiments showed that OGD caused an ~6-fold decrease in Kv7.2 transcript, while levels of mRNAs encoding for other Kv7 subunits were unaffected; western blot experiments showed a parallel reduction in Kv7.2 protein levels. Retigabine also decreased the peak level of dopamine efflux induced by L-glutamate, and attenuated the loss of TTC staining induced by the excitotoxin. These results suggest a role for Kv7.2 in modulating ischemia-evoked caudate damage. PMID:25966943

Special Focus: Effective Instruction in Reading. Strategies for Vocabulary Instruction.

ERIC Educational Resources Information Center

Peters, Ellen, Ed.; Dixon, Robert

1987-01-01

Research based suggestions are presented for effective vocabulary instruction strategies, including: learning new labels; learning concepts; and learning to learn meanings. Regardless of the method chosen, it is crucial that students: demonstrate generalization abilities; be given time to learn new material; periodically review what they learn;…

Still to Learn from Vicarious Learning

ERIC Educational Resources Information Center

Mayes, J. T.

2015-01-01

The term "vicarious learning" was introduced in the 1960s by Bandura, who demonstrated how learning can occur through observing the behaviour of others. Such social learning is effective without the need for the observer to experience feedback directly. More than twenty years later a series of studies on vicarious learning was undertaken…

Methane Bubble Flame Tower--A Spectacularly Engaging Way to Teach Density

ERIC Educational Resources Information Center

Sandoval, Christopher

2012-01-01

This article presents a demonstration using methane bubble flame tower that offers a fun and relatively cheap way of demonstrating what happens when there is a density difference. Teachers can do this as a predict-observe-explain demonstration after the students have learned about density to extend their learning and get into some higher order…

Learning to Use Demonstratives in Conversation: What Do Language Specific Strategies in Turkish Reveal?

ERIC Educational Resources Information Center

Kuntay, Aylin C.; Ozyurek, Asli

2006-01-01

Pragmatic development requires the ability to use linguistic forms, along with non-verbal cues, to focus an interlocutor's attention on a referent during conversation. We investigate the development of this ability by examining how the use of demonstratives is learned in Turkish, where a three-way demonstrative system ("bu,"…

Online EEG-Based Workload Adaptation of an Arithmetic Learning Environment.

PubMed

Walter, Carina; Rosenstiel, Wolfgang; Bogdan, Martin; Gerjets, Peter; Spüler, Martin

2017-01-01

In this paper, we demonstrate a closed-loop EEG-based learning environment, that adapts instructional learning material online, to improve learning success in students during arithmetic learning. The amount of cognitive workload during learning is crucial for successful learning and should be held in the optimal range for each learner. Based on EEG data from 10 subjects, we created a prediction model that estimates the learner's workload to obtain an unobtrusive workload measure. Furthermore, we developed an interactive learning environment that uses the prediction model to estimate the learner's workload online based on the EEG data and adapt the difficulty of the learning material to keep the learner's workload in an optimal range. The EEG-based learning environment was used by 13 subjects to learn arithmetic addition in the octal number system, leading to a significant learning effect. The results suggest that it is feasible to use EEG as an unobtrusive measure of cognitive workload to adapt the learning content. Further it demonstrates that a promptly workload prediction is possible using a generalized prediction model without the need for a user-specific calibration.

Diffusion of novel foraging behaviour in Amazon parrots through social learning.

PubMed

Morales Picard, Alejandra; Hogan, Lauren; Lambert, Megan L; Wilkinson, Anna; Seed, Amanda M; Slocombe, Katie E

2017-03-01

While social learning has been demonstrated in species across many taxa, the role it plays in everyday foraging decisions is not well understood. Investigating social learning during foraging could shed light on the emergence of cultural variation in different groups. We used an open diffusion experiment to examine the spread of a novel foraging technique in captive Amazon parrots. Three groups were tested using a two-action foraging box, including experimental groups exposed to demonstrators using different techniques and control birds. We also examined the influence of agonistic and pilfering behaviour on task acquisition. We found evidence of social learning: more experimental birds than control birds interacted with and opened the box. The birds were, however, no more likely to use the demonstrated technique than the non-demonstrated one, making local or stimulus enhancement the most likely mechanism. Exhibiting aggression was positively correlated with box opening, whilst receiving aggression did not reduce motivation to engage with the box, indicating that willingness to defend access to the box was important in task acquisition. Pilfering food and success in opening the box were also positively correlated; however, having food pilfered did not affect victims' motivation to interact with the box. In a group context, pilfering may promote learning of new foraging opportunities. Although previous studies have demonstrated that psittacines are capable of imitation, in this naturalistic set-up there was no evidence that parrots copied the demonstrated opening technique. Foraging behaviour in wild populations of Amazons could therefore be facilitated by low-fidelity social learning mechanisms.

Neural Correlates of Motor Learning, Transfer of Learning, and Learning to Learn

PubMed Central

Seidler, Rachael D.

2009-01-01

Recent studies on the neural bases of sensorimotor adaptation demonstrate that the cerebellar and striatal thalamocortical pathways contribute to early learning. Transfer of learning involves a reduction in the contribution of early learning networks, and increased reliance on the cerebellum. The neural correlates of learning to learn remain to be determined, but likely involve enhanced functioning of general aspects of early learning. PMID:20016293

NREL and General Motors Announce R&D Partnership to Reduce Cost of

Science.gov Websites

modeling studies to a multiyear National Fuel Cell Electric Vehicle Learning Demonstration. Data from the Learning Demonstration were sent to the National Fuel Cell Technology Evaluation Center (NFCTEC), a data

Sparking Curiosity: How Do You Know What Your Students Are Thinking?

NASA Astrophysics Data System (ADS)

Adams, Wendy K.; Willis, Courtney

2015-11-01

People find it easier to learn about topics that interest them. Recent neuroscience research has demonstrated that memory is improved when learning material about which we are curious. Therefore teaching in the context of what students are interested in should result in improved learning. How do we figure out what our students are curious about? What are they thinking? In this paper we will share techniques that we use in our teaching to determine what our students are highly motivated to learn. Data demonstrating increased interest in physics over the course of the term as well as student learning will also be shared.

Active learning of introductory optics: real-time physics labs, interactive lecture demonstrations and magic

NASA Astrophysics Data System (ADS)

Sokoloff, David R.

2005-10-01

Widespread physics education research has shown that most introductory physics students have difficulty learning essential optics concepts - even in the best of traditional courses, and that well-designed active learning approaches can remedy this problem. This mini-workshop and the associated poster session will provide direct experience with methods for promoting students' active involvement in the learning process in lecture and laboratory. Participants will have hands-on experience with activities from RealTime Physics labs and Interactive Lecture Demonstrations - a learning strategy for large (and small) lectures, including specially designed Optics Magic Tricks. The poster will provide more details on these highly effective curricula.

District Learning Tied to Student Learning

ERIC Educational Resources Information Center

McFadden, Ledyard

2009-01-01

Winners and finalists for the annual Broad Prize for Urban Education have consistently outperformed peer districts serving similar student populations. What makes the difference? These districts consistently demonstrate a learning loop that influences the district's ability to learn, which ultimately influences student opportunities to learn.…

Journal Writing as an Adult Learning Tool. Practice Application Brief No. 22.

ERIC Educational Resources Information Center

Kerka, Sandra

Journals can be valuable tools for fostering adult learning and experience. Research has supported the following assumptions about learning from journals: (1) articulating connections between new and existing knowledge improves learning; (2) writing about learning is a way of demonstrating what has been learned; (3) journal writing accentuates…

The Effect of Student Learning Styles, Race and Gender on Learning Outcomes: The Case of Public Goods

ERIC Educational Resources Information Center

Devaraj, Nirupama; Raman, Jaishankar

2014-01-01

We investigate the impact of active learning techniques, specifically experiment based learning, in a Principles of Economics class. Our case study demonstrates that when using pedagogical techniques intended to facilitate active learning, teachers should be intentional about incorporating components of learning that appeal to students with…

A Playbook for Data: Real-Life Scenario Demonstrates Learning Forward's Data Standard in Action

ERIC Educational Resources Information Center

Hirsh, Stephanie; Hord, Shirley

2012-01-01

This article is an excerpt from "A Playbook for Professional Learning: Putting the Standards Into Action" (Learning Forward, 2012). Written by Learning Forward Executive Director Stephanie Hirsh and Scholar Laureate Shirley Hord, "A Playbook for Professional Learning" provides those who work in professional learning with readily accessible…

Gaussian Processes for Data-Efficient Learning in Robotics and Control.

PubMed

Deisenroth, Marc Peter; Fox, Dieter; Rasmussen, Carl Edward

2015-02-01

Autonomous learning has been a promising direction in control and robotics for more than a decade since data-driven learning allows to reduce the amount of engineering knowledge, which is otherwise required. However, autonomous reinforcement learning (RL) approaches typically require many interactions with the system to learn controllers, which is a practical limitation in real systems, such as robots, where many interactions can be impractical and time consuming. To address this problem, current learning approaches typically require task-specific knowledge in form of expert demonstrations, realistic simulators, pre-shaped policies, or specific knowledge about the underlying dynamics. In this paper, we follow a different approach and speed up learning by extracting more information from data. In particular, we learn a probabilistic, non-parametric Gaussian process transition model of the system. By explicitly incorporating model uncertainty into long-term planning and controller learning our approach reduces the effects of model errors, a key problem in model-based learning. Compared to state-of-the art RL our model-based policy search method achieves an unprecedented speed of learning. We demonstrate its applicability to autonomous learning in real robot and control tasks.

Social learning from humans or conspecifics: differences and similarities between wolves and dogs

PubMed Central

Range, Friederike; Virányi, Zsófia

2013-01-01

Most domestication hypotheses propose that dogs have been selected for enhanced communication and interactions with humans, including learning socially from human demonstrators. However, to what extent these skills are newly derived and to what extent they originate from wolf–wolf interactions is unclear. In order to test for the possible origins of dog social cognition, we need to compare the interactions of wolves and dogs with humans and with conspecifics. Here, we tested identically raised and kept juvenile wolves and dogs in a social learning task with human and conspecific demonstrators. Using a local enhancement task, we found that both wolves and dogs benefitted from a demonstration independent of the demonstrator species in comparison to a control, no demonstration condition. Interestingly, if the demonstrator only pretended to hide food at the target location, wolves and dogs reacted differently: while dogs differentiated between this without-food and with-food demonstration independent of the demonstrator species, wolves only did so in case of human demonstrators. We attribute this finding to wolves being more attentive toward behavioral details of the conspecific models than the dogs: although the demonstrator dogs were trained to execute the demonstration, they disliked the food reward, which might have decreased the interest of the wolves in finding the food reward. Overall, these results suggest that dogs but also wolves can use information provided by both human and conspecific demonstrators in a local enhancement task. Therefore we suggest that a more fine-scale analysis of dog and wolf social learning is needed to determine the effects of domestication. PMID:24363648

Social learning from humans or conspecifics: differences and similarities between wolves and dogs.

PubMed

Range, Friederike; Virányi, Zsófia

2013-01-01

Most domestication hypotheses propose that dogs have been selected for enhanced communication and interactions with humans, including learning socially from human demonstrators. However, to what extent these skills are newly derived and to what extent they originate from wolf-wolf interactions is unclear. In order to test for the possible origins of dog social cognition, we need to compare the interactions of wolves and dogs with humans and with conspecifics. Here, we tested identically raised and kept juvenile wolves and dogs in a social learning task with human and conspecific demonstrators. Using a local enhancement task, we found that both wolves and dogs benefitted from a demonstration independent of the demonstrator species in comparison to a control, no demonstration condition. Interestingly, if the demonstrator only pretended to hide food at the target location, wolves and dogs reacted differently: while dogs differentiated between this without-food and with-food demonstration independent of the demonstrator species, wolves only did so in case of human demonstrators. We attribute this finding to wolves being more attentive toward behavioral details of the conspecific models than the dogs: although the demonstrator dogs were trained to execute the demonstration, they disliked the food reward, which might have decreased the interest of the wolves in finding the food reward. Overall, these results suggest that dogs but also wolves can use information provided by both human and conspecific demonstrators in a local enhancement task. Therefore we suggest that a more fine-scale analysis of dog and wolf social learning is needed to determine the effects of domestication.

Temporally Coordinated Deep Brain Stimulation in the Dorsal and Ventral Striatum Synergistically Enhances Associative Learning.

PubMed

Katnani, Husam A; Patel, Shaun R; Kwon, Churl-Su; Abdel-Aziz, Samer; Gale, John T; Eskandar, Emad N

2016-01-04

The primate brain has the remarkable ability of mapping sensory stimuli into motor behaviors that can lead to positive outcomes. We have previously shown that during the reinforcement of visual-motor behavior, activity in the caudate nucleus is correlated with the rate of learning. Moreover, phasic microstimulation in the caudate during the reinforcement period was shown to enhance associative learning, demonstrating the importance of temporal specificity to manipulate learning related changes. Here we present evidence that extends upon our previous finding by demonstrating that temporally coordinated phasic deep brain stimulation across both the nucleus accumbens and caudate can further enhance associative learning. Monkeys performed a visual-motor associative learning task and received stimulation at time points critical to learning related changes. Resulting performance revealed an enhancement in the rate, ceiling, and reaction times of learning. Stimulation of each brain region alone or at different time points did not generate the same effect.

Summary of Progress on SIG Ft. Ord ESTCP DemVal

DTIC Science & Technology

2007-04-01

We report on progress under an ESTCP demonstration plan dedicated to demonstrating active learning - based UXO detection on an actual former UXO site...Ft. Ord), using EMI data. In addition to describing the details of the active - learning algorithm, we discuss techniques that were required when...terms of two dipole-moment magnitudes and two resonant frequencies. Information-theoretic active learning is then conducted on all anomalies to

Curricular Placement of Academic Service-Learning in Higher Education

ERIC Educational Resources Information Center

Phillips, Amy; Bolduc, Steven R.; Gallo, Michael

2013-01-01

The higher education service-learning literature is rich with case studies, guidelines for service-learning course and program development, and demonstrations of the impact of service-learning on students. Minimal discussion, however, focuses on the "strategic placement" of service-learning in disciplinary curricula, and how curricular…

Reduplicated Words Are Easier to Learn

ERIC Educational Resources Information Center

Ota, Mitsuhiko; Skarabela, Barbora

2016-01-01

Infants' disposition to learn repetitions in the input structure has been demonstrated in pattern generalization (e.g., learning the pattern ABB from the token "ledidi"). This study tested whether a repetition advantage can also be found in lexical learning (i.e., learning the word "lele" vs. "ledi"). Twenty-four…

Intelligence and Changes in Regional Cerebral Glucose Metabolic Rate Following Learning.

ERIC Educational Resources Information Center

Haier, Richard J.; And Others

1992-01-01

A study of eight normal right-handed men demonstrates widespread significant decreases in brain glucose metabolic rate (GMR) following learning a complex computer task, a computer game. Correlations between magnitude of GMR change and intelligence scores are also demonstrated. (SLD)

Model United Nations and Deep Learning: Theoretical and Professional Learning

ERIC Educational Resources Information Center

Engel, Susan; Pallas, Josh; Lambert, Sarah

2017-01-01

This article demonstrates that the purposeful subject design, incorporating a Model United Nations (MUN), facilitated deep learning and professional skills attainment in the field of International Relations. Deep learning was promoted in subject design by linking learning objectives to Anderson and Krathwohl's (2001) four levels of knowledge or…

Developing Learning Theory by Refining Conjectures Embodied in Educational Designs

ERIC Educational Resources Information Center

Sandoval, William A.

2004-01-01

Designed learning environments embody conjectures about learning and instruction, and the empirical study of learning environments allows such conjectures to be refined over time. The construct of embodied conjecture is introduced as a way to demonstrate the theoretical nature of learning environment design and to frame methodological issues in…

On Learning to Talk: Are Principles Derived from the Learning Laboratory Applicable?

ERIC Educational Resources Information Center

Palermo, David S.

While studies in learning and verbal behavior show that learning comes through paired-associate problems, they do not explain the acquisition of language. Three paradigms demonstrate mediation effect in paired-associate learning: response equivalence, stimulus equivalence, and chaining model. By reviewing children's language acquisition patterns…

Computer Mediated Communication and Student Learning in Large Introductory Sociology Classes

ERIC Educational Resources Information Center

Wright, Eric R.; Lawson, Anthony H.

2005-01-01

Over the past several years, scholars of teaching and learning have demonstrated the potential of collaborative learning strategies for improving student learning. This paper examines the use of computer-mediated communication to promote collaborative student learning in large introductory sociology courses. Specifically, we summarize a project we…

Sustainability, Organizational Learning, and Lessons Learned from Aviation

ERIC Educational Resources Information Center

Pourdehnad, John; Smith, Peter A. C.

2012-01-01

Purpose: While the importance of organizational learning for sustainability has been stressed by a number of authors in the literature, the practicalities of how organizational leaders might foster such learning are seldom treated. This paper seeks to demonstrate that there is much that could be learned from the aviation industry about…

Blended Learning in Action: A Practical Guide toward Sustainable Change

ERIC Educational Resources Information Center

Tucker, Catlin R.; Wycoff, Tiffany; Green, Jason T.

2017-01-01

Blended learning has the power to reinvent education, but transitioning to a blended model is challenging. Blended learning requires a fundamentally new approach to learning as well as a new skillset for both teachers and school leaders. Loaded with research, examples, and resources, "Blended Learning in Action" demonstrates the…

Investigation of Using Analytics in Promoting Mobile Learning Support

ERIC Educational Resources Information Center

Visali, Videhi; Swami, Niraj

2013-01-01

Learning analytics can promote pedagogically informed use of learner data, which can steer the progress of technology mediated learning across several learning contexts. This paper presents the application of analytics to a mobile learning solution and demonstrates how a pedagogical sense was inferred from the data. Further, this inference was…

Orthographic learning and the role of text-to-speech software in Dutch disabled readers.

PubMed

Staels, Eva; Van den Broeck, Wim

2015-01-01

In this study, we examined whether orthographic learning can be demonstrated in disabled readers learning to read in a transparent orthography (Dutch). In addition, we tested the effect of the use of text-to-speech software, a new form of direct instruction, on orthographic learning. Both research goals were investigated by replicating Share's self-teaching paradigm. A total of 65 disabled Dutch readers were asked to read eight stories containing embedded homophonic pseudoword targets (e.g., Blot/Blod), with or without the support of text-to-speech software. The amount of orthographic learning was assessed 3 or 7 days later by three measures of orthographic learning. First, the results supported the presence of orthographic learning during independent silent reading by demonstrating that target spellings were correctly identified more often, named more quickly, and spelled more accurately than their homophone foils. Our results support the hypothesis that all readers, even poor readers of transparent orthographies, are capable of developing word-specific knowledge. Second, a negative effect of text-to-speech software on orthographic learning was demonstrated in this study. This negative effect was interpreted as the consequence of passively listening to the auditory presentation of the text. We clarify how these results can be interpreted within current theoretical accounts of orthographic learning and briefly discuss implications for remedial interventions. © Hammill Institute on Disabilities 2013.

Global Learning through Difference: Considerations for Teaching, Learning, and the Internationalization of Higher Education

ERIC Educational Resources Information Center

Kahn, Hilary E.; Agnew, Melanie

2017-01-01

By clarifying what global learning is and how it is essential to higher education, this article considers what global learning provides for teaching, learning, and internationalization in higher education. It demonstrates how the global nature of knowledge and learning in the 21st century requires a re-definition of classrooms and learning…

eLearning techniques supporting problem based learning in clinical simulation.

PubMed

Docherty, Charles; Hoy, Derek; Topp, Helena; Trinder, Kathryn

2005-08-01

This paper details the results of the first phase of a project using eLearning to support students' learning within a simulated environment. The locus was a purpose built clinical simulation laboratory (CSL) where the School's philosophy of problem based learning (PBL) was challenged through lecturers using traditional teaching methods. a student-centred, problem based approach to the acquisition of clinical skills that used high quality learning objects embedded within web pages, substituting for lecturers providing instruction and demonstration. This encouraged student nurses to explore, analyse and make decisions within the safety of a clinical simulation. Learning was facilitated through network communications and reflection on video performances of self and others. Evaluations were positive, students demonstrating increased satisfaction with PBL, improved performance in exams, and increased self-efficacy in the performance of nursing activities. These results indicate that eLearning techniques can help students acquire clinical skills in the safety of a simulated environment within the context of a problem based learning curriculum.

Robots show us how to teach them: feedback from robots shapes tutoring behavior during action learning.

PubMed

Vollmer, Anna-Lisa; Mühlig, Manuel; Steil, Jochen J; Pitsch, Karola; Fritsch, Jannik; Rohlfing, Katharina J; Wrede, Britta

2014-01-01

Robot learning by imitation requires the detection of a tutor's action demonstration and its relevant parts. Current approaches implicitly assume a unidirectional transfer of knowledge from tutor to learner. The presented work challenges this predominant assumption based on an extensive user study with an autonomously interacting robot. We show that by providing feedback, a robot learner influences the human tutor's movement demonstrations in the process of action learning. We argue that the robot's feedback strongly shapes how tutors signal what is relevant to an action and thus advocate a paradigm shift in robot action learning research toward truly interactive systems learning in and benefiting from interaction.

Robots Show Us How to Teach Them: Feedback from Robots Shapes Tutoring Behavior during Action Learning

PubMed Central

Vollmer, Anna-Lisa; Mühlig, Manuel; Steil, Jochen J.; Pitsch, Karola; Fritsch, Jannik; Rohlfing, Katharina J.; Wrede, Britta

2014-01-01

Robot learning by imitation requires the detection of a tutor's action demonstration and its relevant parts. Current approaches implicitly assume a unidirectional transfer of knowledge from tutor to learner. The presented work challenges this predominant assumption based on an extensive user study with an autonomously interacting robot. We show that by providing feedback, a robot learner influences the human tutor's movement demonstrations in the process of action learning. We argue that the robot's feedback strongly shapes how tutors signal what is relevant to an action and thus advocate a paradigm shift in robot action learning research toward truly interactive systems learning in and benefiting from interaction. PMID:24646510

Integration of Robotics and 3D Visualization to Modernize the Expeditionary Warfare Demonstrator (EWD)

DTIC Science & Technology

2009-09-01

his schedule is. I learned most from our informal discussions and collaboration with other industry professionals. Amela was instrumental in allowing...me to effectively analyze, structure and critique my work. I take many professional lessons learned from Amela with me as I leave NPS. Thanks to...observers began learning about maneuver warfare in a large-scale battle. The demonstration was recognized as a huge success after General von Muffling

Influence of learning style on instructional multimedia effects on graduate student cognitive and psychomotor performance.

PubMed

Smith, A Russell; Cavanaugh, Catherine; Jones, Joyce; Venn, John; Wilson, William

2006-01-01

Learning outcomes may improve in graduate healthcare students when attention is given to individual learning styles. Interactive multimedia is one tool shown to increase success in meeting the needs of diverse learners. The purpose of this study was to examine the effect of learning style and type of instruction on physical therapy students' cognitive and psychomotor performance. Participants were obtained by a sample of convenience with students recruited from two physical therapy programs. Twenty-seven students volunteered to participate from Program 1. Twenty-three students volunteered to participate from Program 2. Gregorc learning styles were identified through completion of the Gregorc Style Delineator. Students were randomly assigned to one of two instructional strategies: 1) instructional CD or 2) live demonstration. Differences in cognitive or psychomotor performance following instructional multimedia based on learning style were not demonstrated in this study. Written examination scores improved with both instructional strategies demonstrating no differences between the strategies. Practical examination ankle scores were significantly higher in participants receiving CD instruction than in participants receiving live presentation. Learning style did not significantly affect this improvement. Program 2 performed significantly better on written knee and practical knee and ankle examinations. Learning style had no significant effect on student performance following instruction in clinical skills via interactive multimedia. Future research may include additional measurement instruments assessing other models of learning styles and possible interaction of learning style and instructional strategy on students over longer periods of time, such as a semester or an entire curriculum.

CLEANing the Reward: Counterfactual Actions to Remove Exploratory Action Noise in Multiagent Learning

NASA Technical Reports Server (NTRS)

HolmesParker, Chris; Taylor, Mathew E.; Tumer, Kagan; Agogino, Adrian

2014-01-01

Learning in multiagent systems can be slow because agents must learn both how to behave in a complex environment and how to account for the actions of other agents. The inability of an agent to distinguish between the true environmental dynamics and those caused by the stochastic exploratory actions of other agents creates noise in each agent's reward signal. This learning noise can have unforeseen and often undesirable effects on the resultant system performance. We define such noise as exploratory action noise, demonstrate the critical impact it can have on the learning process in multiagent settings, and introduce a reward structure to effectively remove such noise from each agent's reward signal. In particular, we introduce Coordinated Learning without Exploratory Action Noise (CLEAN) rewards and empirically demonstrate their benefits

Interactive videodisc instruction is an alternative method for learning and performing a critical nursing skill.

PubMed

DeAmicis, P A

1997-01-01

A study was conducted to compare the effectiveness of interactive videodisc instruction (IVDI) with the traditional lecture/demonstration as an alternative method for learning and performing a critical nursing skill. Students were assigned randomly to a treatment group that worked in small groups to complete the IVDI on intravenous therapy skills and a control group receiving the same content in a classroom lecture/demonstration format. After the instruction, each subject performed a re-demonstration of the learned skills using specific guidelines. Results revealed that although the IVDI group scored higher on the overall re-demonstration, there was no significant difference in the ability of the two groups to effectively perform this critical nursing skill. These findings support the use of IVDI as an alternative self-paced, independent study method for learning psychomotor skills and are consistent with previous studies, which indicate that working in small groups on the computer has a positive effect on self-efficacy and achievement.

Selective attention to philopatric models causes directed social learning in wild vervet monkeys.

PubMed

van de Waal, Erica; Renevey, Nathalie; Favre, Camille Monique; Bshary, Redouan

2010-07-22

Human behaviour is often based on social learning, a mechanism that has been documented also in a variety of other vertebrates. However, social learning as a means of problem-solving may be optimal only under specific conditions, and both theoretical work and laboratory experiments highlight the importance of a potential model's identity. Here we present the results from a social learning experiment on six wild vervet monkey groups, where models were either a dominant female or a dominant male. We presented 'artificial fruit' boxes that had doors on opposite, differently coloured ends for access to food. One option was blocked during the demonstration phase, creating consistent demonstrations of one possible solution. Following demonstrations we found a significantly higher participation rate and same-door manipulation in groups with female models compared to groups with male models. These differences appeared to be owing to selective attention of bystanders to female model behaviour rather than owing to female tolerance. Our results demonstrate the favoured role of dominant females as a source for 'directed' social learning in a species with female philopatry. Our findings imply that migration does not necessarily lead to an exchange of socially acquired information within populations, potentially causing highly localized traditions.

Elevated Arc/Arg 3.1 protein expression in the basolateral amygdala following auditory trace-cued fear conditioning.

PubMed

Chau, Lily S; Prakapenka, Alesia; Fleming, Stephen A; Davis, Ashley S; Galvez, Roberto

2013-11-01

The underlying neuronal mechanisms of learning and memory have been heavily explored using associative learning paradigms. Two of the more commonly employed learning paradigms have been contextual and delay fear conditioning. In fear conditioning, a subject learns to associate a neutral stimulus (conditioned stimulus; CS), such as a tone or the context of the room, with a fear provoking stimulus (unconditioned stimulus; US), such as a mild footshock. Utilizing these two paradigms, various analyses have elegantly demonstrated that the amygdala plays a role in both fear-related associative learning paradigms. However, the amygdala's involvement in trace fear conditioning, a forebrain-dependent fear associative learning paradigm that has been suggested to tap into higher cognitive processes, has not been closely investigated. Furthermore, to our knowledge, the specific amygdala nuclei involved with trace fear conditioning has not been examined. The present study used Arc expression as an activity marker to determine the amygdala's involvement in trace fear associative learning and to further explore involvement of specific amygdalar nuclei. Arc is an immediate early gene that has been shown to be associated with neuronal activation and is believed to be necessary for neuronal plasticity. Findings from the present study demonstrated that trace-conditioned mice, compared to backward-conditioned (stimulation-control), delay-conditioned and naïve mice, exhibited elevated amygdalar Arc expression in the basolateral (BLA) but not the central (CeA) or the lateral amygdala (LA). These findings are consistent with previous reports demonstrating that the amygdala plays a critical role in trace conditioning. Furthermore, these findings parallel studies demonstrating hippocampal-BLA activation following contextual fear conditioning, suggesting that trace fear conditioning and contextual fear conditioning may involve similar amygdala nuclei. Together, findings from this study demonstrate similarities in the pathway for trace and contextual fear conditioning, and further suggest possible underlying mechanisms for acquisition and consolidation of these two types of fear-related learning. Copyright © 2013 Elsevier Inc. All rights reserved.

Interactive lecture demonstrations, active learning, and the ALOP project

NASA Astrophysics Data System (ADS)

Lakshminarayanan, Vasudevan

2011-05-01

There is considerable evidence from the physics education literature that traditional approaches are ineffective in teaching physics concepts. A better teaching method is to use the active learning environment, which can be created using interactive lecture demonstrations. Based on the active learning methodology and within the framework of the UNESCO mandate in physics education and introductory physics, the ALOP project (active learning in optics and photonics) was started in 2003, to provide a focus on an experimental area that is adaptable and relevant to research and educational conditions in many developing countries. This project is discussed in this paper.

Real-Time Global Nonlinear Aerodynamic Modeling for Learn-To-Fly

NASA Technical Reports Server (NTRS)

Morelli, Eugene A.

2016-01-01

Flight testing and modeling techniques were developed to accurately identify global nonlinear aerodynamic models for aircraft in real time. The techniques were developed and demonstrated during flight testing of a remotely-piloted subscale propeller-driven fixed-wing aircraft using flight test maneuvers designed to simulate a Learn-To-Fly scenario. Prediction testing was used to evaluate the quality of the global models identified in real time. The real-time global nonlinear aerodynamic modeling algorithm will be integrated and further tested with learning adaptive control and guidance for NASA Learn-To-Fly concept flight demonstrations.

Learning from Demonstration: Generalization via Task Segmentation

NASA Astrophysics Data System (ADS)

Ettehadi, N.; Manaffam, S.; Behal, A.

2017-10-01

In this paper, a motion segmentation algorithm design is presented with the goal of segmenting a learned trajectory from demonstration such that each segment is locally maximally different from its neighbors. This segmentation is then exploited to appropriately scale (dilate/squeeze and/or rotate) a nominal trajectory learned from a few demonstrations on a fixed experimental setup such that it is applicable to different experimental settings without expanding the dataset and/or retraining the robot. The algorithm is computationally efficient in the sense that it allows facile transition between different environments. Experimental results using the Baxter robotic platform showcase the ability of the algorithm to accurately transfer a feeding task.

Vertical transmission of learned signatures in a wild parrot

PubMed Central

Berg, Karl S.; Delgado, Soraya; Cortopassi, Kathryn A.; Beissinger, Steven R.; Bradbury, Jack W.

2012-01-01

Learned birdsong is a widely used animal model for understanding the acquisition of human speech. Male songbirds often learn songs from adult males during sensitive periods early in life, and sing to attract mates and defend territories. In presumably all of the 350+ parrot species, individuals of both sexes commonly learn vocal signals throughout life to satisfy a wide variety of social functions. Despite intriguing parallels with humans, there have been no experimental studies demonstrating learned vocal production in wild parrots. We studied contact call learning in video-rigged nests of a well-known marked population of green-rumped parrotlets (Forpus passerinus) in Venezuela. Both sexes of naive nestlings developed individually unique contact calls in the nest, and we demonstrate experimentally that signature attributes are learned from both primary care-givers. This represents the first experimental evidence for the mechanisms underlying the transmission of a socially acquired trait in a wild parrot population. PMID:21752824

Community-University Partnerships for Mutual Learning.

ERIC Educational Resources Information Center

Gelmon, Sherril B.; Holland, Barbara A.; Seifer, Sarena D.; Shinnamon, Anu; Connors, Kara

1998-01-01

Discusses what has been learned about building school/community partnerships through the "Health Professions Schools in Service to the Nation Program," a national demonstration program of service-learning in health-professions education. Issues include: the challenge of distinguishing service learning from clinical experience; community attitudes…

Contextualizing Learning Scenarios According to Different Learning Management Systems

ERIC Educational Resources Information Center

Drira, R.; Laroussi, M.; Le Pallec, X.; Warin, B.

2012-01-01

In this paper, we first demonstrate that an instructional design process of Technology Enhanced Learning (TEL) systems based on a Model Driven Approach (MDA) addresses the limits of Learning Technology Standards (LTS), such as SCORM and IMS-LD. Although these standards ensure the interoperability of TEL systems across different Learning Management…

Throw out Learning Objectives! In Support of a New Taxonomy

ERIC Educational Resources Information Center

Gander, Sharon L.

2006-01-01

In the right hands, learning objectives are great tools for clarifying thinking, breaking down learning into component parts, creating a logical order to learning, and demonstrating that a learning intervention is successful. Mostly, however, they have become cliches. With the industry's tendency to use them as pro forma media bites, they tend to…

Remembering Math: The Design of Digital Learning Objects to Spark Professional Learning

ERIC Educational Resources Information Center

Halverson, Richard; Wolfenstein, Moses; Williams, Caroline C.; Rockman, Charles

2009-01-01

This article describes how the design of digital learning objects can spark professional learning. The challenge was to build learning objects that would help experienced special education teachers, who had been teaching in math classes, to demonstrate their proficiency in middle and secondary school mathematics on the PRAXIS examination. While…

Understanding Aboriginal Learning Ideology through Storywork with Elders

ERIC Educational Resources Information Center

Atleo, Marlene R.

2009-01-01

Five Nuu-chah-nulth Elders engaged in the examination of a Nuu-chah-nulth story for what they considered learning. A network of eight learning archetypes inhabited the story to demonstrate a range of learning strategies. The Elders identified features central to a cultural learning project, which included prenatal care and grandparent teaching,…

Utilizing Formative Assessments to Guide Student Learning in an Interactive Physics Learning Environment

ERIC Educational Resources Information Center

Lee, Young-Jin

2011-01-01

In the last decades, many education researchers have been trying to use computerized learning environments to enhance student learning. Without proper instructional supports and guidance, however, students often failed to acquire knowledge from computer-based learning activities. The objective of this study was to demonstrate how research-based…

Opportunities and Challenges for Teacher Professional Development: A Case of Collaborative Learning Community in South Korea

ERIC Educational Resources Information Center

Park, Minjeong; So, Kyunghee

2014-01-01

This study investigates how characteristics of a collaborative professional learning activity support and hinder teacher learning and growth by examining the experiences of three Korean secondary teachers who participated in a school-initiated collaborative teacher learning project. The findings demonstrated that this learning opportunity…

Outcomes-Based Assessment and Learning: Trialling Change in a Postgraduate Civil Engineering Course

ERIC Educational Resources Information Center

El-Maaddawy, Tamer; Deneen, Christopher

2017-01-01

This paper aims to demonstrate how assessment tasks can function within an outcomes-based learning framework to evaluate student attainment of learning outcomes. An outcomes-based learning framework designed to integrate teaching, learning, and assessment activities was developed and implemented in a civil engineering master-level course. The…

Incidental Learning of Rewarded Associations Bolsters Learning on an Associative Task

ERIC Educational Resources Information Center

Freedberg, Michael; Schacherer, Jonathan; Hazeltine, Eliot

2016-01-01

Reward has been shown to change behavior as a result of incentive learning (by motivating the individual to increase their effort) and instrumental learning (by increasing the frequency of a particular behavior). However, Palminteri et al. (2011) demonstrated that reward can also improve the incidental learning of a motor skill even when…

Pygmalion in Media-Based Learning: Effects of Quality Expectancies on Learning Outcomes

ERIC Educational Resources Information Center

Fries, Stefan; Horz, Holger; Haimerl, Charlotte

2006-01-01

Two studies investigated how quality expectations affect students' outcomes of media-based learning. Experiment 1 (N=62) demonstrated that students expecting a high-end computer-based training programme learned most, whereas students expecting a programme of ambiguous quality learned least and students having no expectations performed in between.…

Learning to use demonstratives in conversation: what do language specific strategies in Turkish reveal?

PubMed

Küntay, Aylin C; Ozyürek, Asli; Planck, Max

2006-05-01

Pragmatic development requires the ability to use linguistic forms, along with non-verbal cues, to focus an interlocutor's attention on a referent during conversation. We investigate the development of this ability by examining how the use of demonstratives is learned in Turkish, where a three-way demonstrative system (bu, su, o) obligatorily encodes both distance contrasts (i.e. proximal and distal) and absence or presence of the addressee's visual attention on the referent. A comparison of the demonstrative use by Turkish children (6 four- and 6 six-year-olds) and 6 adults during conversation shows that adultlike use of attention directing demonstrative, su, is not mastered even at the age of six, while the distance contrasts are learned earlier. This language specific development reveals that designing referential forms in consideration of recipient's attentional status during conversation is a pragmatic feat that takes more than six years to develop.

Imitation in Undergraduate Teaching and Learning

ERIC Educational Resources Information Center

Zhou, Jiangyuan; Guo, Wei

2016-01-01

Research in developmental psychology and neuroscience has demonstrated the critical role of imitation in human learning. Self-report questionnaires collected from 456 undergraduate students in two U.S. institutions and one Chinese institution demonstrated that undergraduate students from both U.S. and Chinese cultures used various imitations in…

Techniques for Programming Visual Demonstrations.

ERIC Educational Resources Information Center

Gropper, George L.

Visual demonstrations may be used as part of programs to deliver both content objectives and process objectives. Research has shown that learning of concepts is easier, more accurate, and more broadly applied when it is accompanied by visual examples. The visual examples supporting content learning should emphasize both discrimination and…

Cognitive Support for Learning Computer-Based Tasks Using Animated Demonstration

ERIC Educational Resources Information Center

Chen, Chun-Ying

2016-01-01

This study investigated the influence of cognitive support for learning computer-based tasks using animated demonstration (AD) on instructional efficiency. Cognitive support included (1) segmentation and learner control introducing interactive devices that allow content sequencing through a navigational menu, and content pacing through stop and…

Paradoxes of a Long Life Learning: An Exploration of Peter Jarvis's Contribution to Experiential Learning Theory

ERIC Educational Resources Information Center

Dyke, Martin

2017-01-01

The paper explores the work of Peter Jarvis related to learning with particular reference to his definitions of learning and his models of the learning process. This exploration will consider different approaches to experiential learning and demonstrate the contribution Jarvis has made, noting how his writing on the subject has changed over time.…

Learning styles and the prospective ophthalmologist.

PubMed

Modi, Neil; Williams, Olayinka; Swampillai, Andrew J; Waqar, Salman; Park, Jonathan; Kersey, Thomas L; Sleep, Tamsin

2015-04-01

Understanding the learning styles of individual trainees may enable trainers to tailor an educational program and optimise learning. Surgical trainees have previously been shown to demonstrate a tendency towards particular learning styles. We seek to clarify the relationship between learning style and learned surgical performance using a simulator, prior to surgical training. The Kolb Learning Style Inventory was administered to a group of thirty junior doctors. Participants were then asked to perform a series of tasks using the EyeSi virtual reality cataract surgery simulator (VR Magic, Mannheim, Germany). All completed a standard introductory programme to eliminate learning curve. They then undertook four attempts of level 4 forceps module binocularly. Total score, odometer movement (mm), corneal area injured (mm(2)), lens area injured (mm(2)) and total time taken (seconds) recorded. Mean age was 31.6 years. No significant correlation was found between any learning style and any variable on the EyeSi cataract surgery simulator. There is a predominant learning style amongst surgical residents. There is however no demonstrable learning style that results in a better (or worse) performance on the EyeSi surgery simulator and hence in learning and performing cataract surgery.

Learning of grammar-like visual sequences by adults with and without language-learning disabilities.

PubMed

Aguilar, Jessica M; Plante, Elena

2014-08-01

Two studies examined learning of grammar-like visual sequences to determine whether a general deficit in statistical learning characterizes this population. Furthermore, we tested the hypothesis that difficulty in sustaining attention during the learning task might account for differences in statistical learning. In Study 1, adults with normal language (NL) or language-learning disability (LLD) were familiarized with the visual artificial grammar and then tested using items that conformed or deviated from the grammar. In Study 2, a 2nd sample of adults with NL and LLD were presented auditory word pairs with weak semantic associations (e.g., groom + clean) along with the visual learning task. Participants were instructed to attend to visual sequences and to ignore the auditory stimuli. Incidental encoding of these words would indicate reduced attention to the primary task. In Studies 1 and 2, both groups demonstrated learning and generalization of the artificial grammar. In Study 2, neither the NL nor the LLD group appeared to encode the words presented during the learning phase. The results argue against a general deficit in statistical learning for individuals with LLD and demonstrate that both NL and LLD learners can ignore extraneous auditory stimuli during visual learning.

Deep neural networks for direct, featureless learning through observation: The case of two-dimensional spin models

NASA Astrophysics Data System (ADS)

Mills, Kyle; Tamblyn, Isaac

2018-03-01

We demonstrate the capability of a convolutional deep neural network in predicting the nearest-neighbor energy of the 4 ×4 Ising model. Using its success at this task, we motivate the study of the larger 8 ×8 Ising model, showing that the deep neural network can learn the nearest-neighbor Ising Hamiltonian after only seeing a vanishingly small fraction of configuration space. Additionally, we show that the neural network has learned both the energy and magnetization operators with sufficient accuracy to replicate the low-temperature Ising phase transition. We then demonstrate the ability of the neural network to learn other spin models, teaching the convolutional deep neural network to accurately predict the long-range interaction of a screened Coulomb Hamiltonian, a sinusoidally attenuated screened Coulomb Hamiltonian, and a modified Potts model Hamiltonian. In the case of the long-range interaction, we demonstrate the ability of the neural network to recover the phase transition with equivalent accuracy to the numerically exact method. Furthermore, in the case of the long-range interaction, the benefits of the neural network become apparent; it is able to make predictions with a high degree of accuracy, and do so 1600 times faster than a CUDA-optimized exact calculation. Additionally, we demonstrate how the neural network succeeds at these tasks by looking at the weights learned in a simplified demonstration.

A conceptual cognitive architecture for robots to learn behaviors from demonstrations in robotic aid area.

PubMed

Tan, Huan; Liang, Chen

2011-01-01

This paper proposes a conceptual hybrid cognitive architecture for cognitive robots to learn behaviors from demonstrations in robotic aid situations. Unlike the current cognitive architectures, this architecture puts concentration on the requirements of the safety, the interaction, and the non-centralized processing in robotic aid situations. Imitation learning technologies for cognitive robots have been integrated into this architecture for rapidly transferring the knowledge and skills between human teachers and robots.

Learning-Based Curriculum Development

ERIC Educational Resources Information Center

Nygaard, Claus; Hojlt, Thomas; Hermansen, Mads

2008-01-01

This article is written to inspire curriculum developers to centre their efforts on the learning processes of students. It presents a learning-based paradigm for higher education and demonstrates the close relationship between curriculum development and students' learning processes. The article has three sections: Section "The role of higher…

Urban partnership agreement and congestion reduction demonstration programs : lessons learned on congestion pricing from the Seattle and Atlanta household travel behavior surveys.

DOT National Transportation Integrated Search

2014-04-01

This paper presents lessons learned from household traveler surveys administered in Seattle and Atlanta as part of the evaluation of the Urban Partnership Agreement and Congestion Reduction Demonstration Programs. The surveys use a two-stage panel su...

Classroom Walkthroughs to Improve Teaching and Learning

ERIC Educational Resources Information Center

Kachur, Donald S.; Stout, Judy; Edwards, Claudia

2010-01-01

This book demonstrates the many ways classroom walkthroughs can be used for continuous, systemic, long-range school improvement. Woven throughout the book are 18 different models of walkthroughs that have been successfully implemented in schools across the country. An effective tool for improving teaching and learning, this book demonstrates that…

A Referential Communication Demonstration versus a Lecture-Only Control: Learning Benefits

ERIC Educational Resources Information Center

Balch, William R.

2014-01-01

To evaluate a demonstration involving active and cooperative learning, 40 students in a cognitive psychology course and 132 students in an introductory psychology course completed a brief multiple-choice pretest on referential communication. Two days later, randomly assigned students either participated in a classroom referential communication…

Application of Tablet PCs to Lecture Demonstrations on Optical Mineralogy

ERIC Educational Resources Information Center

Hoisch, Thomas D.; Austin, Barbara A.; Newell, Shawn L.; Manone, Mark F.

2010-01-01

Learning optical mineralogy requires students to integrate a complex theory with microscope manipulations and image interpretation. To assist student learning, we performed lecture demonstrations during which digital photomicrographs were taken and delivered to students using Tablet PCs, whereupon they were imported into note-taking software and…

E-Learning Challenges in the Arab World: Revelations from a Case Study Profile

ERIC Educational Resources Information Center

Abouchedid, Kamal; Eid, George M.

2004-01-01

The overwhelming traditional knowledge delivery system for higher education in the Arab world demonstrates the pronounced information technology (IT) gap between Arab countries and the developed world. This study demonstrates the problems and possibilities of implementing e-learning in Arab educational institutions through analysing the attitudes…

Competitive STDP Learning of Overlapping Spatial Patterns.

PubMed

Krunglevicius, Dalius

2015-08-01

Spike-timing-dependent plasticity (STDP) is a set of Hebbian learning rules firmly based on biological evidence. It has been demonstrated that one of the STDP learning rules is suited for learning spatiotemporal patterns. When multiple neurons are organized in a simple competitive spiking neural network, this network is capable of learning multiple distinct patterns. If patterns overlap significantly (i.e., patterns are mutually inclusive), however, competition would not preclude trained neuron's responding to a new pattern and adjusting synaptic weights accordingly. This letter presents a simple neural network that combines vertical inhibition and Euclidean distance-dependent synaptic strength factor. This approach helps to solve the problem of pattern size-dependent parameter optimality and significantly reduces the probability of a neuron's forgetting an already learned pattern. For demonstration purposes, the network was trained for the first ten letters of the Braille alphabet.

Humour production may enhance observational learning of a new tool-use action in 18-month-old infants.

PubMed

Esseily, Rana; Rat-Fischer, Lauriane; Somogyi, Eszter; O'Regan, Kevin John; Fagard, Jacqueline

2016-01-01

Many studies have shown that making children laugh enhances certain cognitive capacities such as attention, motivation, perception and/or memory, which in turn enhance learning. However, no study thus far has investigated whether laughing has an effect on learning earlier in infancy. The goal of this study was to see whether using humour with young infants in a demonstration of a complex tool-use task can enhance their learning. Fifty-three 18-month-old infants participated in this study and were included either in a humorous or a control demonstration group. In both groups infants observed an adult using a tool to retrieve an out-of-reach toy. What differed between groups was that in the humorous demonstration group, instead of playing with the toy, the adult threw it on the floor immediately after retrieval. The results show that infants who laughed at the demonstration in the humorous demonstration group reproduced significantly more frequent target actions than infants who did not laugh and those in the control group. This effect is discussed with regard to individual differences in terms of temperament and social capacities as well as positive emotion and dopamine release.

Asymptotically Optimal Motion Planning for Learned Tasks Using Time-Dependent Cost Maps

PubMed Central

Bowen, Chris; Ye, Gu; Alterovitz, Ron

2015-01-01

In unstructured environments in people’s homes and workspaces, robots executing a task may need to avoid obstacles while satisfying task motion constraints, e.g., keeping a plate of food level to avoid spills or properly orienting a finger to push a button. We introduce a sampling-based method for computing motion plans that are collision-free and minimize a cost metric that encodes task motion constraints. Our time-dependent cost metric, learned from a set of demonstrations, encodes features of a task’s motion that are consistent across the demonstrations and, hence, are likely required to successfully execute the task. Our sampling-based motion planner uses the learned cost metric to compute plans that simultaneously avoid obstacles and satisfy task constraints. The motion planner is asymptotically optimal and minimizes the Mahalanobis distance between the planned trajectory and the distribution of demonstrations in a feature space parameterized by the locations of task-relevant objects. The motion planner also leverages the distribution of the demonstrations to significantly reduce plan computation time. We demonstrate the method’s effectiveness and speed using a small humanoid robot performing tasks requiring both obstacle avoidance and satisfaction of learned task constraints. Note to Practitioners Motivated by the desire to enable robots to autonomously operate in cluttered home and workplace environments, this paper presents an approach for intuitively training a robot in a manner that enables it to repeat the task in novel scenarios and in the presence of unforeseen obstacles in the environment. Based on user-provided demonstrations of the task, our method learns features of the task that are consistent across the demonstrations and that we expect should be repeated by the robot when performing the task. We next present an efficient algorithm for planning robot motions to perform the task based on the learned features while avoiding obstacles. We demonstrate the effectiveness of our motion planner for scenarios requiring transferring a powder and pushing a button in environments with obstacles, and we plan to extend our results to more complex tasks in the future. PMID:26279642

The Evolution of Facultative Conformity Based on Similarity.

PubMed

Efferson, Charles; Lalive, Rafael; Cacault, Maria Paula; Kistler, Deborah

2016-01-01

Conformist social learning can have a pronounced impact on the cultural evolution of human societies, and it can shape both the genetic and cultural evolution of human social behavior more broadly. Conformist social learning is beneficial when the social learner and the demonstrators from whom she learns are similar in the sense that the same behavior is optimal for both. Otherwise, the social learner's optimum is likely to be rare among demonstrators, and conformity is costly. The trade-off between these two situations has figured prominently in the longstanding debate about the evolution of conformity, but the importance of the trade-off can depend critically on the flexibility of one's social learning strategy. We developed a gene-culture coevolutionary model that allows cognition to encode and process information about the similarity between naive learners and experienced demonstrators. Facultative social learning strategies that condition on perceived similarity evolve under certain circumstances. When this happens, facultative adjustments are often asymmetric. Asymmetric adjustments mean that the tendency to follow the majority when learners perceive demonstrators as similar is stronger than the tendency to follow the minority when learners perceive demonstrators as different. In an associated incentivized experiment, we found that social learners adjusted how they used social information based on perceived similarity, but adjustments were symmetric. The symmetry of adjustments completely eliminated the commonly assumed trade-off between cases in which learners and demonstrators share an optimum versus cases in which they do not. In a second experiment that maximized the potential for social learners to follow their preferred strategies, a few social learners exhibited an inclination to follow the majority. Most, however, did not respond systematically to social information. Additionally, in the complete absence of information about their similarity to demonstrators, social learners were unwilling to make assumptions about whether they shared an optimum with demonstrators. Instead, social learners simply ignored social information even though this was the only information available. Our results suggest that social cognition equips people to use conformity in a discriminating fashion that moderates the evolutionary trade-offs that would occur if conformist social learning was rigidly applied.

The Evolution of Facultative Conformity Based on Similarity

PubMed Central

Efferson, Charles; Lalive, Rafael; Cacault, Maria Paula; Kistler, Deborah

2016-01-01

Conformist social learning can have a pronounced impact on the cultural evolution of human societies, and it can shape both the genetic and cultural evolution of human social behavior more broadly. Conformist social learning is beneficial when the social learner and the demonstrators from whom she learns are similar in the sense that the same behavior is optimal for both. Otherwise, the social learner’s optimum is likely to be rare among demonstrators, and conformity is costly. The trade-off between these two situations has figured prominently in the longstanding debate about the evolution of conformity, but the importance of the trade-off can depend critically on the flexibility of one’s social learning strategy. We developed a gene-culture coevolutionary model that allows cognition to encode and process information about the similarity between naive learners and experienced demonstrators. Facultative social learning strategies that condition on perceived similarity evolve under certain circumstances. When this happens, facultative adjustments are often asymmetric. Asymmetric adjustments mean that the tendency to follow the majority when learners perceive demonstrators as similar is stronger than the tendency to follow the minority when learners perceive demonstrators as different. In an associated incentivized experiment, we found that social learners adjusted how they used social information based on perceived similarity, but adjustments were symmetric. The symmetry of adjustments completely eliminated the commonly assumed trade-off between cases in which learners and demonstrators share an optimum versus cases in which they do not. In a second experiment that maximized the potential for social learners to follow their preferred strategies, a few social learners exhibited an inclination to follow the majority. Most, however, did not respond systematically to social information. Additionally, in the complete absence of information about their similarity to demonstrators, social learners were unwilling to make assumptions about whether they shared an optimum with demonstrators. Instead, social learners simply ignored social information even though this was the only information available. Our results suggest that social cognition equips people to use conformity in a discriminating fashion that moderates the evolutionary trade-offs that would occur if conformist social learning was rigidly applied. PMID:28002461

Reception Learning and Self-Discovery Learning in Histology: Students' Perceptions and Their Implications for Assessing the Effectiveness of Different Learning Modalities

ERIC Educational Resources Information Center

Campos-Sanchez, Antonio; Martin-Piedra, Miguel-Angel; Carriel, Victor; Gonzalez-Andrades, Miguel; Garzon, Ingrid; Sanchez-Quevedo, Maria-Carmen; Alaminos, Miguel

2012-01-01

Two questionnaires were used to investigate students' perceptions of their motivation to opt for reception learning (RL) or self-discovery learning (SDL) in histology and their choices of complementary learning strategies (CLS). The results demonstrated that the motivation to attend RL sessions was higher than the motivation to attend SDL to gain…

Voices of Strong Democracy: Concepts and Models for Service-Learning in Communication Studies. AAHE's Series on Service-Learning in the Disciplines.

ERIC Educational Resources Information Center

Droge, David, Ed.; Murphy, Bren Ortega, Ed.

This volume is part of a series of 18 monographs on service learning and the academic disciplines. These essays demonstrate some "best practices" for service-learning, providing rigorous learning experiences for students and high-quality service to the community. A Preface by James L. Applegate and Sherwyn P. Morreale, "Service-Learning in…

Learning for Today: The Interaction between Pedagogy, Learning Spaces and Technology

ERIC Educational Resources Information Center

Selinger, Michelle

2011-01-01

A new pedagogy is emerging, placing students at the centre of the learning process and encouraging teachers to draw from a larger repertoire of strategies and skills to lead interdisciplinary and project-based work. The best learning is authentic--engaging students in their own learning in practical and real-life contexts that demonstrate the…

Supporting Case-Based Learning in Information Security with Web-Based Technology

ERIC Educational Resources Information Center

He, Wu; Yuan, Xiaohong; Yang, Li

2013-01-01

Case-based learning has been widely used in many disciplines. As an effective pedagogical method, case-based learning is also being used to support teaching and learning in the domain of information security. In this paper, we demonstrate case-based learning in information security by sharing our experiences in using a case study to teach security…

Learning Increases the Survival of Newborn Neurons Provided that Learning Is Difficult to Achieve and Successful

ERIC Educational Resources Information Center

Curlik, Daniel M., II; Shors, Tracey J.

2011-01-01

Learning increases neurogenesis by increasing the survival of new cells generated in the adult hippocampal formation [Shors, T. J. Saving new brain cells. "Scientific American," 300, 46-52, 2009]. However, only some types of learning are effective. Recent studies demonstrate that animals that learn the conditioned response (CR) but require more…

Targeting Academic Programs to Student Diversity Utilizing Learning Styles and Learning-Study Strategies.

ERIC Educational Resources Information Center

Grimes, Sue K.

1995-01-01

A diagnostic, prescriptive model was utilized (n=394) in identification of learning styles and learning-study strategies of diverse student groups and in the analysis of prescriptive methods to address their specific needs. High-risk groups demonstrated auditory, tactile concrete, and group learning style preferences and were weaker on cognitive,…

"Involvement in Learning" Revisited: Lessons We Have Learned.

ERIC Educational Resources Information Center

Astin, Alexander W.

1999-01-01

Originally published in March/April 1996, reviews the interconnections between two national reports, "Involvement in Learning," and the "Student Learning Imperative." Focuses on the issue of shared values and demonstrates how student affairs professionals can utilize the most recent research to realize the full potential of the…

VALUE: Valid Assessment of Learning in Undergraduate Education

ERIC Educational Resources Information Center

Rhodes, Terrel L.

2008-01-01

This chapter discusses the Association of American Colleges and Universities' (AAC&U's) Valid Assessment of Learning in Undergraduate Education (VALUE) project, which aims to demonstrate that faculty across the country share fundamental expectations about student learning on all of the essential learning outcomes deemed critical for student…

Return of the Pig: Standards for Learning Improvement

ERIC Educational Resources Information Center

Fulcher, Keston H.; Smith, Kristen L.; Sanchez, Elizabeth R. H.; Ames, Allison J.; Meixner, Cara

2017-01-01

Higher education has made impressive progress concerning student learning outcomes assessment practices. Yet--despite the assumption that better assessment would lead to better student learning--few examples of demonstrable student learning improvement exist at the academic degree or university levels. In 2014 Fulcher, Good, Coleman, and Smith…

A Route for Every Learner: Universal Design for Learning (UDL) as a Framework for Supporting Learning and Improving Achievement for All Learners in Maryland, Prekindergarten through Higher Education

ERIC Educational Resources Information Center

Maryland State Department of Education, 2011

2011-01-01

Universal Design for Learning (UDL) is a framework for curriculum design, instruction, and assessment that gives all students equal opportunities to learn and to demonstrate what they have learned. UDL is built on the premise that there is not one kind of learning. Learning differs across tasks, across development, and among individuals. UDL is…

Patients with Parkinson's disease learn to control complex systems-an indication for intact implicit cognitive skill learning.

PubMed

Witt, Karsten; Daniels, Christine; Daniel, Victoria; Schmitt-Eliassen, Julia; Volkmann, Jens; Deuschl, Günther

2006-01-01

Implicit memory and learning mechanisms are composed of multiple processes and systems. Previous studies demonstrated a basal ganglia involvement in purely cognitive tasks that form stimulus response habits by reinforcement learning such as implicit classification learning. We will test the basal ganglia influence on two cognitive implicit tasks previously described by Berry and Broadbent, the sugar production task and the personal interaction task. Furthermore, we will investigate the relationship between certain aspects of an executive dysfunction and implicit learning. To this end, we have tested 22 Parkinsonian patients and 22 age-matched controls on two implicit cognitive tasks, in which participants learned to control a complex system. They interacted with the system by choosing an input value and obtaining an output that was related in a complex manner to the input. The objective was to reach and maintain a specific target value across trials (dynamic system learning). The two tasks followed the same underlying complex rule but had different surface appearances. Subsequently, participants performed an executive test battery including the Stroop test, verbal fluency and the Wisconsin card sorting test (WCST). The results demonstrate intact implicit learning in patients, despite an executive dysfunction in the Parkinsonian group. They lead to the conclusion that the basal ganglia system affected in Parkinson's disease does not contribute to the implicit acquisition of a new cognitive skill. Furthermore, the Parkinsonian patients were able to reach a specific goal in an implicit learning context despite impaired goal directed behaviour in the WCST, a classic test of executive functions. These results demonstrate a functional independence of implicit cognitive skill learning and certain aspects of executive functions.

Cetacean vocal learning and communication.

PubMed

Janik, Vincent M

2014-10-01

The cetaceans are one of the few mammalian clades capable of vocal production learning. Evidence for this comes from synchronous changes in song patterns of baleen whales and experimental work on toothed whales in captivity. While baleen whales like many vocal learners use this skill in song displays that are involved in sexual selection, toothed whales use learned signals in individual recognition and the negotiation of social relationships. Experimental studies demonstrated that dolphins can use learned signals referentially. Studies on wild dolphins demonstrated how this skill appears to be useful in their own communication system, making them an interesting subject for comparative communication studies. Copyright © 2014. Published by Elsevier Ltd.

Learning where to feed: the use of social information in flower-visiting Pallas' long-tongued bats (Glossophaga soricina).

PubMed

Rose, Andreas; Kolar, Miriam; Tschapka, Marco; Knörnschild, Mirjam

2016-03-01

Social learning is a widespread phenomenon among vertebrates that influences various patterns of behaviour and is often reported with respect to foraging behaviour. The use of social information by foraging bats was documented in insectivorous, carnivorous and frugivorous species, but there are little data whether flower-visiting nectarivorous bats (Phyllostomidae: Glossophaginae) can acquire information about food from other individuals. In this study, we conducted an experiment with a demonstrator-observer paradigm to investigate whether flower-visiting Pallas' long-tongued bats (Glossophaga soricina) are able to socially learn novel flower positions via observation of, or interaction with, knowledgeable conspecifics. The results demonstrate that flower-visiting G. soricina are able to use social information for the location of novel flower positions and can thereby reduce energy-costly search efforts. This social transmission is explainable as a result of local enhancement; learning bats might rely on both visual and echo-acoustical perception and are likely to eavesdrop on auditory cues that are emitted by feeding conspecifics. We additionally tested the spatial memory capacity of former demonstrator bats when retrieving a learned flower position, and the results indicate that flower-visiting bats remember a learned flower position after several weeks.

Improving ECG Competence in Medical Trainees in a UK District General Hospital

PubMed Central

McAloon, Christopher; Leach, Helen; Gill, Simrat; Aluwalia, Arun; Trevelyan, Jasper

2014-01-01

Background Competency in electrocardiogram (ECG) interpretation is central to undergraduate and postgraduate clinical training. Studies have demonstrated ECGs are interpreted sub-optimally. Our study compares the effectiveness of two learning strategies to improve competence and confidence. Method A 1-month prospective randomized study compared the strategies in two cohorts: undergraduate third year medical students and postgraduate foundation year one (FY1) doctors. Both had blinded randomization to one of these learning strategies: focused teaching program (FTP) and self-directed learning (SDL). All volunteers completed a confidence questionnaire before and after allocation learning strategy and an ECG recognition multiple choice question (MCQ) paper at the end of the learning period. Results The FTP group of undergraduates demonstrated a significant difference in successfully interpreting “ventricular tachycardia” (P = 0.046) and “narrow complex tachycardia” (P = 0.009) than the SDL group. Participant confidence increased in both learning strategies. FTP confidence demonstrated a greater improvement than SDL for both cohorts. Conclusion A dedicated teaching program can improve trainee confidence and competence in ECG interpretation. A larger benefit is observed in undergraduates and those undertaking a FTP. PMID:28392875

Non-physics peer demonstrators in undergraduate laboratories: a study of students’ perceptions

NASA Astrophysics Data System (ADS)

Braun, Michael; Kirkup, Les

2016-01-01

Laboratory demonstrators play a crucial role in facilitating students’ learning in physics subjects. Inspired by the success of peer-led activities, we introduced peer demonstrators to support student learning in first-year physics subjects that enrol students not intending to major in physics. Surveys were administered to 1700 students over 4 years in four subjects to examine student perceptions of how demonstrators assisted them in the laboratory. Scores awarded to peer demonstrators by students were no lower than those awarded to demonstrators traditionally employed in the first year physics laboratory. These latter demonstrators were drawn mainly from the ranks of physics research students. The findings validate the recruitment of peer demonstrators and will be used to inform the recruitment and support programmes for laboratory demonstrators.

A general-purpose machine learning framework for predicting properties of inorganic materials

DOE PAGES

Ward, Logan; Agrawal, Ankit; Choudhary, Alok; ...

2016-08-26

A very active area of materials research is to devise methods that use machine learning to automatically extract predictive models from existing materials data. While prior examples have demonstrated successful models for some applications, many more applications exist where machine learning can make a strong impact. To enable faster development of machine-learning-based models for such applications, we have created a framework capable of being applied to a broad range of materials data. Our method works by using a chemically diverse list of attributes, which we demonstrate are suitable for describing a wide variety of properties, and a novel method formore » partitioning the data set into groups of similar materials to boost the predictive accuracy. In this manuscript, we demonstrate how this new method can be used to predict diverse properties of crystalline and amorphous materials, such as band gap energy and glass-forming ability.« less

Correlation of the summary method with learning styles.

PubMed

Sarikcioglu, Levent; Senol, Yesim; Yildirim, Fatos B; Hizay, Arzu

2011-09-01

The summary is the last part of the lesson but one of the most important. We aimed to study the relationship between the preference of the summary method (video demonstration, question-answer, or brief review of slides) and learning styles. A total of 131 students were included in the present study. An inventory was prepared to understand the students' learning styles, and a satisfaction questionnaire was provided to determine the summary method selection. The questionnaire and inventory were collected and analyzed. A comparison of the data revealed that the summary method with video demonstration received the highest score among all the methods tested. Additionally, there were no significant differences between learning styles and summary method with video demonstration. We suggest that such a summary method should be incorporated into neuroanatomy lessons. Since anatomy has a large amount of visual material, we think that it is ideally suited for this summary method.

A general-purpose machine learning framework for predicting properties of inorganic materials

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

Ward, Logan; Agrawal, Ankit; Choudhary, Alok

A very active area of materials research is to devise methods that use machine learning to automatically extract predictive models from existing materials data. While prior examples have demonstrated successful models for some applications, many more applications exist where machine learning can make a strong impact. To enable faster development of machine-learning-based models for such applications, we have created a framework capable of being applied to a broad range of materials data. Our method works by using a chemically diverse list of attributes, which we demonstrate are suitable for describing a wide variety of properties, and a novel method formore » partitioning the data set into groups of similar materials to boost the predictive accuracy. In this manuscript, we demonstrate how this new method can be used to predict diverse properties of crystalline and amorphous materials, such as band gap energy and glass-forming ability.« less

Form over Substance: Learning Objectives in the Business Core

ERIC Educational Resources Information Center

Stokes, Leonard; Rosetti, Joseph L.; King, Michelle

2010-01-01

While members of the business faculty community have been advocating active learning in the classroom, it appears that textbooks encourage learning from a passive perspective. A review of learning objectives from 16 textbooks used in Financial Accounting, Managerial Accounting, Finance, and Marketing demonstrates a focus on basically the same set…

Numbers Are Not Enough. Why e-Learning Analytics Failed to Inform an Institutional Strategic Plan

ERIC Educational Resources Information Center

Macfadyen, Leah P.; Dawson, Shane

2012-01-01

Learning analytics offers higher education valuable insights that can inform strategic decision-making regarding resource allocation for educational excellence. Research demonstrates that learning management systems (LMSs) can increase student sense of community, support learning communities and enhance student engagement and success, and LMSs…

Lifelong Learning Policies, Paradoxes and Possibilities

ERIC Educational Resources Information Center

Tett, Lyn

2014-01-01

This paper argues that there are many ways of conceptualising lifelong learning and examines EU and Scottish lifelong learning policies in order to identify their underlying assumptions. Through an analysis of these policies, it is demonstrated that they draw on a number of inter-related fallacies that prioritise lifelong learning mainly in…

Learning Profiles: The Learning Crisis Is Not (Mostly) about Enrollment

ERIC Educational Resources Information Center

Sandefur, Justin; Pritchett, Lant; Beatty, Amanda

2016-01-01

The differential patterns of grade progression have direct implications for the calculation of learning profiles. Researchers measure learning in primary school using survey data on reading and math skills of a nationally representative, population-based sample of children in India, Pakistan, Kenya, Tanzania, and Uganda. Research demonstrates that…

Analysing a Web-Based E-Commerce Learning Community: A Case Study in Brazil.

ERIC Educational Resources Information Center

Joia, Luiz Antonio

2002-01-01

Demonstrates the use of a Web-based participative virtual learning environment for graduate students in Brazil enrolled in an electronic commerce course in a Masters in Business Administration program. Discusses learning communities; computer-supported collaborative work and collaborative learning; influences on student participation; the role of…

The Effects of Socio-Scientific Issue Based Inquiry Learning on Pupils' Representations of Landscape

ERIC Educational Resources Information Center

Kärkkäinen, Sirpa; Keinonen, Tuula; Kukkonen, Jari; Juntunen, Seija; Ratinen, Ilkka

2017-01-01

Research has demonstrated that socio-scientific issues based inquiry learning has significant advantages for learning outcomes and students' motivation. Further, a successful understanding of landscapes in environmental and geographical education can be achieved by combining informal learning environments with school education. Therefore this case…

Student Engagement and Blended Learning: Making the Assessment Connection

ERIC Educational Resources Information Center

Vaughan, Norman

2014-01-01

There is an increased focus on student engagement and blended approaches to learning in higher education. This article demonstrates how collaborative learning applications and a blended approach to learning can be used to design and support assessment activities that increase levels of student engagement with course concepts, their peers, faculty…

Effects of Example Variability and Prior Knowledge in How Students Learn to Solve Equations

ERIC Educational Resources Information Center

Guo, Jian-Peng; Yang, Ling-Yan; Ding, Yi

2014-01-01

Researchers have consistently demonstrated that multiple examples are better than one example in facilitating learning because the comparison evoked by multiple examples supports learning and transfer. However, research outcomes are unclear regarding the effects of example variability and prior knowledge on learning from comparing multiple…

Integration of Technology in Teaching and Learning: Comprehensive Initiatives Enhance Student Engagement and Learning

ERIC Educational Resources Information Center

Nebbergall, Allison

2012-01-01

As technology increasingly transforms our daily lives, educators too are seeking strategies and resources that leverage technology to improve student learning. Research demonstrates that high-quality professional development, digital standards-based content, and personalized learning plans can increase student achievement, engagement, and…

A Social-Cognitive Framework for Pedagogical Agents as Learning Companions

ERIC Educational Resources Information Center

Kim, Yanghee; Baylor, Amy L.

2006-01-01

Teaching and learning are highly social activities. Seminal psychologists such as Vygotsky, Piaget, and Bandura have theorized that social interaction is a key mechanism in the process of learning and development. In particular, the benefits of peer interaction for learning and motivation in classrooms have been broadly demonstrated through…

A Delphi Study on Collaborative Learning in Distance Education: The Faculty Perspective

ERIC Educational Resources Information Center

O'Neill, Susan; Scott, Murray; Conboy, Kieran

2011-01-01

This paper focuses on the factors that influence collaborative learning in distance education. Distance education has been around for many years and the use of collaborative learning techniques in distance education is becoming increasingly popular. Several studies have demonstrated the superiority of collaborative learning over traditional modes…

Opportunities for Learning-Based Conversations in High School Mathematics

ERIC Educational Resources Information Center

McFeetors, Janelle

2015-01-01

Conversations as moments for interpersonal and intimate turning round of ideas for the purpose of growth are well-defined within curriculum inquiry. Interactions among grade 12 students in this study demonstrate the possibility of learning to learn mathematics through conversation. Attending to opportunities for learning-based conversations,…

Do Open Educational Resources and Cloud Classroom Really Improve Students' Learning?

ERIC Educational Resources Information Center

Tsai, Chia-Wen; Shen, Pei-Di

2014-01-01

More and more educational institutions are using educational technologies and online learning materials to help students achieve satisfactory learning effects. However, not all teachers are able to prepare and design digital learning materials for students. This research attempted to empirically demonstrate the effects of applying open educational…

Understanding Resistance: Reflections on Race and Privilege through Service-Learning

ERIC Educational Resources Information Center

Espino, Michelle M.; Lee, Jenny J.

2011-01-01

Service-learning has been hailed as an effective means to bridge classroom learning with practical application in the local context. Numerous studies have demonstrated the educational value of service-learning, particularly the potential to build awareness and appreciation for diversity. Students' resistance to even acknowledging issues of…

Learning and Working in Groups.

ERIC Educational Resources Information Center

1999

This document contains three symposium papers on learning and working in groups. "Collaborating in Public with the Opposition: A Study of the Complex Meaning of Learning in a Cross Boundary Work Group" (Marjorie H. Carkhuff) reports on a study demonstrating that great personal, professional, and team member learning is foundational to the work…

Fluid Intelligence and Discriminative Operant Learning of Reinforcement Contingencies in a Fixed Ratio 3 Schedule

ERIC Educational Resources Information Center

Lozano, J. H.; Hernandez, J. M.; Rubio, V. J.; Santacreu, J.

2011-01-01

Although intelligence has traditionally been identified as "the ability to learn" (Peterson, 1925), this relationship has been questioned in simple operant learning tasks (Spielberger, 1962). Nevertheless, recent pieces of research have demonstrated a strong and significant correlation between associative learning measures and intelligence…

An Examination of the Impact of Learning Communities on Job

ERIC Educational Resources Information Center

Wilmes, David M.

2012-01-01

The purpose of this study was to examine the relationship between learning community participation and job/major congruence. Previous research has demonstrated that learning communities are effective vehicles for promoting student and institutional outcomes. However, few studies have examined the impact of learning communities on alumni or career…

Statistical Learning Is Related to Early Literacy-Related Skills

ERIC Educational Resources Information Center

Spencer, Mercedes; Kaschak, Michael P.; Jones, John L.; Lonigan, Christopher J.

2015-01-01

It has been demonstrated that statistical learning, or the ability to use statistical information to learn the structure of one's environment, plays a role in young children's acquisition of linguistic knowledge. Although most research on statistical learning has focused on language acquisition processes, such as the segmentation of words from…

Mood Moderates the Effect of Self-Generation during Learning

ERIC Educational Resources Information Center

Schindler, Julia; Richter, Tobias; Eyßer, Carolin

2017-01-01

Generating information, compared to reading, improves learning and enhances long-term retention of the learned content. This so-called generation effect has been demonstrated repeatedly for recall and recognition of single words. However, before adopting generating as a learning strategy in educational contexts, conditions moderating the effect…

Prioritizing Active Learning: An Exploration of Gateway Courses in Political Science

ERIC Educational Resources Information Center

Archer, Candace C.; Miller, Melissa K.

2011-01-01

Prior research in political science and other disciplines demonstrates the pedagogical and practical benefits of active learning. Less is known, however, about the extent to which active learning is used in political science classrooms. This study assesses the prioritization of active learning in "gateway" political science courses, paying…

Analyses of Student Learning in Global Change

NASA Astrophysics Data System (ADS)

Takle, E. S.; Moser, H.; Sorensen, E. K.

2004-12-01

The Global Change course at Iowa State University is a senior undergraduate and graduate level course that has been delivered over the internet with online dialog and learning activities since 1995. Students may enroll in the course as a distance education course, but in doing so they engage in dialog with students in the conventional on-campus face-to-face course. Online delivery and student participation offer opportunities for promoting use of critical thinking skills and collaborative learning not available in face-to-face environments. Students are required to research, post, and defend with authoritative information their positions on a variety of global change issues and specifically identify how they have demonstrated use of critical thinking skills in their online postings. Threaded dialog is used for structuring interactions toward promoting collaborative learning. We analyze collaborative learning by use of a rubric based on the theory of language games. By random selection of 1,350 online dialog comments posted over the last 10 years we evaluated student response to requirements for demonstrating critical thinking skills and collaboration in learning. We found that, by itself, the requirement of demonstrating critical thinking skills in online dialog was insufficient in promoting collaborative learned as measured by the standards of language game theory. But we also found that if an online comment clearly defines a situation and makes a clear expectation of a response, the likelihood is high that a game will be created. And if a game is established, there is a high probability that it will be closed, thereby giving evidence that collaborative learning had occurred. We conclude that a key component in collaborative online learning lies in establishing a lead-off comment that provides sufficient background information to clearly define an engaging situation. It also must include a clear expectation that a response is expected that will provide dialog participants an opportunity to demonstrate critical thinking skills in their responding comments.

Known and Unknown Weaknesses in Software Animated Demonstrations (Screencasts): A Study in Self-Paced Learning Settings

ERIC Educational Resources Information Center

Palaigeorgiou, George; Despotakis, Theofanis

2010-01-01

Learning about computers continues to be regarded as a rather informal and complex landscape dominated by individual exploratory and opportunistic approaches, even for students and instructors in Computer Science Departments. During the last two decades, software animated demonstrations (SADs), also known as screencasts, have attracted particular…

Elementary School English Teachers' Professional Learning from Teaching Demonstrations as Professional Development

ERIC Educational Resources Information Center

Chien, Chin-Wen

2017-01-01

This study used interviews, observations and documentary evidence to analyze the professional learning of sixteen elementary school English teachers and two expert teachers during the pre-observation conference, observation, and post-observation conference from three-step teaching demonstrations. This study has the following major findings. First,…

Student Learning Support Programmes That Demonstrate Tangible Impact on Retention, Pass Rates & Completion. 2nd Edition

ERIC Educational Resources Information Center

Manalo, Emmanuel, Ed.; Marshall, Jenny, Ed.; Fraser, Cath, Ed.

2010-01-01

This report comprises summations and brief case descriptions of some of the effective programmes and other support mechanisms that New Zealand Tertiary Learning Advisors (TLAs) provide for students in universities, polytechnics, institutes of technology, and other tertiary institutions. The programmes demonstrate tangible impact on student…

Memory and Learning: A Case Study.

ERIC Educational Resources Information Center

Webster, Raymond E.

1986-01-01

The usefulness of the Learning Efficency Test (LET), an approach to assessing the learning efficiency and short-term memory recall capacity in children, is described via a case study demonstrating the test's use to develop instructional strategies. (CL)

Leveraging Intermediaries to Expand Work-Based Learning. Connecting the Classroom to Careers: The State's Role in Work-Based Learning

ERIC Educational Resources Information Center

Advance CTE: State Leaders Connecting Learning to Work, 2016

2016-01-01

Work-based learning is an educational strategy that offers students an opportunity to reinforce and deepen their classroom learning, explore future career fields and demonstrate their skills in an authentic setting. Managing work-based learning requires layers of coordination, which is typically done by an individual or organizational…

Compute-to-Learn: Authentic Learning via Development of Interactive Computer Demonstrations within a Peer-Led Studio Environment

ERIC Educational Resources Information Center

Jafari, Mina; Welden, Alicia Rae; Williams, Kyle L.; Winograd, Blair; Mulvihill, Ellen; Hendrickson, Heidi P.; Lenard, Michael; Gottfried, Amy; Geva, Eitan

2017-01-01

In this paper, we report on the implementation of a novel compute-to-learn pedagogy, which is based upon the theories of situated cognition and meaningful learning. The "compute-to-learn" pedagogy is designed to simulate an authentic research experience as part of the undergraduate curriculum, including project development, teamwork,…

Does a Preschool Social and Emotional Learning Intervention Pay Off for Classroom Instruction and Children's Behavior and Academic Skills? Evidence from the Foundations of Learning Project

ERIC Educational Resources Information Center

Morris, Pamela; Millenky, Megan; Raver, C. Cybele; Jones, Stephanie M.

2013-01-01

This article tests the hypothesis that children's learning environment will improve through a social and emotional learning (SEL) intervention that provides preschool teachers with new skills to manage children's disruptive behavior by reporting results from the Foundations of Learning (FOL) Demonstration, a place-randomized, experimental…

Patterns and Rates of Learning in Two Problem-Based Learning Courses Using Outcome Based Assessment and Elaboration Theory

ERIC Educational Resources Information Center

Kuruganti, Usha; Needham, Ted; Zundel, Pierre

2012-01-01

The concept of "practice makes perfect" was examined in this work in the context of effective learning. Specifically, we wanted to know how much practice was needed for students to demonstrate mastery of learning outcomes. Student learning patterns in two different university courses that use a similar education approach involving…

The Effects of Online Interactive Games on High School Students' Achievement and Motivation in History Learning

ERIC Educational Resources Information Center

Lin, Kuan-Cheng; Wei, Yu Che; Hung, Jason C.

2012-01-01

Many studies demonstrate that Digital Game Based Learning (DGBL) can foster learning effect. The purpose of this study is to survey whether the online game in junior high school students can encourage learning effect in Taiwan's History. So, the research applied Interactive Game-based Learning System (IGLS) to junior high history teaching as an…

Using Mixed-Modality Learning Strategies via e-Learning for Second Language Vocabulary Acquisition

ERIC Educational Resources Information Center

Yang, Fang-Chuan Ou; Wu, Wen-Chi Vivian

2015-01-01

This study demonstrated an e-learning system, MyEVA, based on a mixed-modality vocabulary strategy in assisting learners of English as a second language (L2 learners) to improve their vocabulary. To explore the learning effectiveness of MyEVA, the study compared four vocabulary-learning techniques, MyEVA in preference mode, MyEVA in basic mode, an…

Intrinsic Motivation of Chinese Learning in Predicting Online Learning Self-Efficacy and Flow Experience Relevant to Students' Learning Progress

ERIC Educational Resources Information Center

Hong, Jon-Chao; Hwang, Ming-Yueh; Tai, Kai-Hsin; Lin, Pei-Hsin

2017-01-01

Students of Southeast Asian Heritage Learning Chinese (SSAHLC) in Taiwan have frequently demonstrated difficulty with traditional Chinese (a graphical character) radical recognition due to their limited exposure to the written language form since childhood. In this study, we designed a Chinese radical learning game (CRLG), which adopted a drill…

Development, direction, and damage limitation: social learning in domestic fowl.

PubMed

Nicol, Christine J

2004-02-01

This review highlights two areas of particular interest in the study of social learning in fowl. First, the role of social learning in the development of feeding and foraging behavior in young chicks and older birds is described. The role of the hen as a demonstrator and possible teacher is considered, and the subsequent social influence of brood mates and other companions on food avoidance and food preference learning is discussed. Second, the way in which work on domestic fowl has contributed to an understanding of the importance of directed social learning is examined. The well-characterized hierarchical social organization of small chicken flocks has been used to design studies which demonstrate that the probability of social transmission is strongly influenced by social relationships between birds. The practical implications of understanding the role of social learning in the spread of injurious behaviors in this economically important species are briefly considered.

The cost of selective attention in category learning: Developmental differences between adults and infants

PubMed Central

Best, Catherine A.; Yim, Hyungwook; Sloutsky, Vladimir M.

2013-01-01

Selective attention plays an important role in category learning. However, immaturities of top-down attentional control during infancy coupled with successful category learning suggest that early category learning is achieved without attending selectively. Research presented here examines this possibility by focusing on category learning in infants (6–8 months old) and adults. Participants were trained on a novel visual category. Halfway through the experiment, unbeknownst to participants, the to-be-learned category switched to another category, where previously relevant features became irrelevant and previously irrelevant features became relevant. If participants attend selectively to the relevant features of the first category, they should incur a cost of selective attention immediately after the unknown category switch. Results revealed that adults demonstrated a cost, as evidenced by a decrease in accuracy and response time on test trials as well as a decrease in visual attention to newly relevant features. In contrast, infants did not demonstrate a similar cost of selective attention as adults despite evidence of learning both to-be-learned categories. Findings are discussed as supporting multiple systems of category learning and as suggesting that learning mechanisms engaged by adults may be different from those engaged by infants. PMID:23773914

Electrophysiological evidence of heterogeneity in visual statistical learning in young children with ASD.

PubMed

Jeste, Shafali S; Kirkham, Natasha; Senturk, Damla; Hasenstab, Kyle; Sugar, Catherine; Kupelian, Chloe; Baker, Elizabeth; Sanders, Andrew J; Shimizu, Christina; Norona, Amanda; Paparella, Tanya; Freeman, Stephanny F N; Johnson, Scott P

2015-01-01

Statistical learning is characterized by detection of regularities in one's environment without an awareness or intention to learn, and it may play a critical role in language and social behavior. Accordingly, in this study we investigated the electrophysiological correlates of visual statistical learning in young children with autism spectrum disorder (ASD) using an event-related potential shape learning paradigm, and we examined the relation between visual statistical learning and cognitive function. Compared to typically developing (TD) controls, the ASD group as a whole showed reduced evidence of learning as defined by N1 (early visual discrimination) and P300 (attention to novelty) components. Upon further analysis, in the ASD group there was a positive correlation between N1 amplitude difference and non-verbal IQ, and a positive correlation between P300 amplitude difference and adaptive social function. Children with ASD and a high non-verbal IQ and high adaptive social function demonstrated a distinctive pattern of learning. This is the first study to identify electrophysiological markers of visual statistical learning in children with ASD. Through this work we have demonstrated heterogeneity in statistical learning in ASD that maps onto non-verbal cognition and adaptive social function. © 2014 John Wiley & Sons Ltd.

Behaviorism, Latent Learning, and Cognitive Maps: Needed Revisions in Introductory Psychology Textbooks

PubMed Central

Jensen, Robert

2006-01-01

This paper critically assesses the scholarship in introductory psychology textbooks in relation to the topic of latent learning. A review of the treatment of latent learning in 48 introductory psychology textbooks published between 1948 and 2004, with 21 of these texts published since 1999, reveals that the scholarship on the topic of latent learning demonstrated in introductory textbooks warrants improvement. Errors that persist in textbooks include the assertion that the latent learning experiments demonstrate unequivocally that reinforcement was not necessary for learning to occur, that behavioral theories could not account for the results of the latent learning experiments, that B. F. Skinner was an S-R association behaviorist who argued that reinforcement is necessary for learning to occur, and that because behavioral theories (including that of B. F. Skinner) were unable explain the results of the latent learning experiments the cognitive map invoked by Edward Tolman is the only explanation for latent learning. Finally, the validity of the cognitive map is typically accepted without question. Implications of the presence of these errors for students and the discipline are considered. Lastly, remedies are offered to improve the scholarship found in introductory psychology textbooks. PMID:22478463

Application of Instructional Design Principles in Developing an Online Information Literacy Curriculum.

PubMed

Mi, Misa

2016-01-01

An online information literacy curriculum was developed as an intervention to engage students in independent study and self-assessment of their learning needs and learning outcomes, develop proficiency in information skills, and foster lifelong learning. This column demonstrates how instructional design principles were applied to create the learning experiences integrated into various courses of the medical curriculum to promote active learning of information skills and maximize self-directed learning outcomes for lifelong learning.

Opportunities for learning in an introductory undergraduate human anatomy and physiology course

NASA Astrophysics Data System (ADS)

Montplaisir, Lisa Marie

2003-10-01

The purpose of this study was to explore the course conditions that support the development of meaningful student learning in an introductory undergraduate human anatomy and physiology course. The study was conducted during an 8-week summer-session at a small mid-western university. Classroom observations and taped recordings of class sessions were used to determine content episodes within the instructional unit, opportunities for learning created by the instructor, demonstrations of information processing by the students, and the ways in which the instructor used the Personal Response System (PRS). Student interviews were used to determine students' level of understanding of pre-test and post-test items. Student interviews and a questionnaire were used to determine students' perceptions of the PRS as a learning tool. Findings reveal that the instructor had different expectations of students when posing verbal questions in-class than he had when posing PRS questions. The use of verbal questions did not permit demonstrations of student understanding; however, the use of the PRS did result in demonstrations of student understanding. Questions posed via the use of the PRS were categorized according to cognitive level. The cognitive level of the questions increased with time over the instructional unit and within the content episodes. Students demonstrated deeper understanding of the topics after instruction than they did before instruction. Students reported more in-class thinking about the content, more discussion of the content with their neighbors, more regular class attendance, more opportunities for deeper learning, and a general preference for the PRS over traditional lectures. Findings of the study indicate that the instructional decisions about the use of questions influences the opportunities for students to process information and demonstrate their understanding of the content and that students valued these opportunities. A better understanding of the conditions that promote meaningful student learning may help us make decisions that result in improved student learning in our own classes.

Using Elearning techniques to support problem based learning within a clinical simulation laboratory.

PubMed

Docherty, Charles; Hoy, Derek; Topp, Helena; Trinder, Kathryn

2004-01-01

This paper details the results of the first phase of a project that used eLearning to support students' learning within a simulated environment. The locus was a purpose built Clinical Simulation Laboratory (CSL) where the School's newly adopted philosophy of Problem Based Learning (PBL) was challenged through lecturers reverting to traditional teaching methods. The solution, a student-centred, problem-based approach to the acquisition of clinical skills was developed using learning objects embedded within web pages that substituted for lecturers providing instruction and demonstration. This allowed lecturers to retain their facilitator role, and encouraged students to explore, analyse and make decisions within the safety of a clinical simulation. Learning was enhanced through network communications and reflection on video performances of self and others. Evaluations were positive, students demonstrating increased satisfaction with PBL, improved performance in exams, and increased self-efficacy in the performance of nursing activities. These results indicate that an elearning approach can support PBL in delivering a student centred learning experience.

Students' Studying and Approaches to Learning in Introductory Biology

PubMed Central

2004-01-01

This exploratory study was conducted in an introductory biology course to determine 1) how students used the large lecture environment to create their own learning tasks during studying and 2) whether meaningful learning resulted from the students' efforts. Academic task research from the K–12 education literature and student approaches to learning research from the postsecondary education literature provided the theoretical framework for the mixed methods study. The subject topic was cell division. Findings showed that students 1) valued lectures to develop what they believed to be their own understanding of the topic; 2) deliberately created and engaged in learning tasks for themselves only in preparation for the unit exam; 3) used course resources, cognitive operations, and study strategies that were compatible with surface and strategic, rather than deep, approaches to learning; 4) successfully demonstrated competence in answering familiar test questions aligned with their surface and strategic approaches to studying and learning; and 5) demonstrated limited meaningful understanding of the significance of cell division processes. Implications for introductory biology education are discussed. PMID:15592598

On-Orbit Engineering and Vehicle Integration Poster Presentation

NASA Technical Reports Server (NTRS)

Heimerdinger, Madison

2014-01-01

One of the duties of the MER Managers is getting the consoles to review and sign Electronic Flight Notes (EFN) and Mission Action Requests (Chit) before they are due. Chits and EFNs and are accessible through the Mission Control Center - Houston (MCC-H) Gateway. Chits are the official means of documenting questions and answers, technical direction, real-time changes to Flight Rules (FR) and procedures, request for analysis, etc. between various consoles concerning on-orbit operations. EFNs are documents used by the Flight Control Team (FCT) to communicate precise details between console positions and manage real time changes to FR and Systems Operation Data File (SODF) procedures. On GMT 2013/345 the External Active Thermal Control System (EATCS) on the Columbus (COL) Moderate Temperature Loop (MTL) Interface Heat Exchanger (IFHX) shut down due to low temperatures. Over the next couple of days, the core temperature of COL MT IFHX dropped due to the failure of the Flow Control Valve (FCV). After the temperature drop was discovered, heaters were turned on to bring the temperatures back to nominal. After the incident occurred, a possible freeze threat was discovered that could have ruptured the heat exchanger. The COL MT IFHX rupturing would be considered a catastrophic failure and potentially result in a loss of the vehicle and/or the lives of the International Space Station (ISS) crew members

A comparative analysis of well-to-wheel primary energy demand and greenhouse gas emissions for the operation of alternative and conventional vehicles in Switzerland, considering various energy carrier production pathways

NASA Astrophysics Data System (ADS)

Yazdanie, Mashael; Noembrini, Fabrizio; Dossetto, Lionel; Boulouchos, Konstantinos

2014-03-01

This study provides a comprehensive analysis of well-to-wheel (WTW) primary energy demand and greenhouse gas (GHG) emissions for the operation of conventional and alternative passenger vehicle drivetrains. Results are determined based on a reference vehicle, drivetrain/production process efficiencies, and lifecycle inventory data specific to Switzerland. WTW performance is compared to a gasoline internal combustion engine vehicle (ICEV). Both industrialized and novel hydrogen and electricity production pathways are evaluated. A strong case is presented for pluggable electric vehicles (PEVs) due to their high drivetrain efficiency. However, WTW performance strongly depends on the electricity source. A critical electricity mix can be identified which divides optimal drivetrain performance between the EV, ICEV, and plug-in hybrid vehicle. Alternative drivetrain and energy carrier production pathways are also compared by natural resource. Fuel cell vehicle (FCV) performance proves to be on par with PEVs for energy carrier (EC) production via biomass and natural gas resources. However, PEVs outperform FCVs via solar energy EC production pathways. ICE drivetrains using alternative fuels, particularly biogas and CNG, yield remarkable WTW energy and emission reductions as well, indicating that alternative fuels, and not only alternative drivetrains, play an important role in the transition towards low-emission vehicles in Switzerland.

Teaching torque with 5E learning strategy: an off-center disk case

NASA Astrophysics Data System (ADS)

Balta, Nuri

2018-01-01

In this paper, five simple demonstrations with an off-center disk that can be easily constructed and demonstrated in science class are described along with the 5E learning strategy. These demonstrations can be used to help students develop an understanding of the relationship between the centre of mass and torque. These STEM activities are appropriate for high school or first-year college physics, and are expected to engage students during physics courses.

"Model age-based" and "copy when uncertain" biases in children's social learning of a novel task.

PubMed

Wood, Lara A; Harrison, Rachel A; Lucas, Amanda J; McGuigan, Nicola; Burdett, Emily R R; Whiten, Andrew

2016-10-01

Theoretical models of social learning predict that individuals can benefit from using strategies that specify when and whom to copy. Here the interaction of two social learning strategies, model age-based biased copying and copy when uncertain, was investigated. Uncertainty was created via a systematic manipulation of demonstration efficacy (completeness) and efficiency (causal relevance of some actions). The participants, 4- to 6-year-old children (N=140), viewed both an adult model and a child model, each of whom used a different tool on a novel task. They did so in a complete condition, a near-complete condition, a partial demonstration condition, or a no-demonstration condition. Half of the demonstrations in each condition incorporated causally irrelevant actions by the models. Social transmission was assessed by first responses but also through children's continued fidelity, the hallmark of social traditions. Results revealed a bias to copy the child model both on first response and in continued interactions. Demonstration efficacy and efficiency did not affect choice of model at first response but did influence solution exploration across trials, with demonstrations containing causally irrelevant actions decreasing exploration of alternative methods. These results imply that uncertain environments can result in canalized social learning from specific classes of model. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Evaluation of a faculty development program aimed at increasing residents' active learning in lectures.

PubMed

Desselle, Bonnie C; English, Robin; Hescock, George; Hauser, Andrea; Roy, Melissa; Yang, Tong; Chauvin, Sheila W

2012-12-01

Active engagement in the learning process is important to enhance learners' knowledge acquisition and retention and the development of their thinking skills. This study evaluated whether a 1-hour faculty development workshop increased the use of active teaching strategies and enhanced residents' active learning and thinking. Faculty teaching in a pediatrics residency participated in a 1-hour workshop (intervention) approximately 1 month before a scheduled lecture. Participants' responses to a preworkshop/postworkshop questionnaire targeted self-efficacy (confidence) for facilitating active learning and thinking and providing feedback about workshop quality. Trained observers assessed each lecture (3-month baseline phase and 3-month intervention phase) using an 8-item scale for use of active learning strategies and a 7-item scale for residents' engagement in active learning. Observers also assessed lecturer-resident interactions and the extent to which residents were asked to justify their answers. Responses to the workshop questionnaire (n  =  32/34; 94%) demonstrated effectiveness and increased confidence. Faculty in the intervention phase demonstrated increased use of interactive teaching strategies for 6 items, with 5 reaching statistical significance (P ≤ .01). Residents' active learning behaviors in lectures were higher in the intervention arm for all 7 items, with 5 reaching statistical significance. Faculty in the intervention group demonstrated increased use of higher-order questioning (P  =  .02) and solicited justifications for answers (P  =  .01). A 1-hour faculty development program increased faculty use of active learning strategies and residents' engagement in active learning during resident core curriculum lectures.

Off-line simulation inspires insight: A neurodynamics approach to efficient robot task learning.

PubMed

Sousa, Emanuel; Erlhagen, Wolfram; Ferreira, Flora; Bicho, Estela

2015-12-01

There is currently an increasing demand for robots able to acquire the sequential organization of tasks from social learning interactions with ordinary people. Interactive learning-by-demonstration and communication is a promising research topic in current robotics research. However, the efficient acquisition of generalized task representations that allow the robot to adapt to different users and contexts is a major challenge. In this paper, we present a dynamic neural field (DNF) model that is inspired by the hypothesis that the nervous system uses the off-line re-activation of initial memory traces to incrementally incorporate new information into structured knowledge. To achieve this, the model combines fast activation-based learning to robustly represent sequential information from single task demonstrations with slower, weight-based learning during internal simulations to establish longer-term associations between neural populations representing individual subtasks. The efficiency of the learning process is tested in an assembly paradigm in which the humanoid robot ARoS learns to construct a toy vehicle from its parts. User demonstrations with different serial orders together with the correction of initial prediction errors allow the robot to acquire generalized task knowledge about possible serial orders and the longer term dependencies between subgoals in very few social learning interactions. This success is shown in a joint action scenario in which ARoS uses the newly acquired assembly plan to construct the toy together with a human partner. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Role of Intelligence in Social Learning.

PubMed

Vostroknutov, Alexander; Polonio, Luca; Coricelli, Giorgio

2018-05-02

Studies in cultural evolution have uncovered many types of social learning strategies that are adaptive in certain environments. The efficiency of these strategies also depends on the individual characteristics of both the observer and the demonstrator. We investigate the relationship between intelligence and the ways social and individual information is utilised to make decisions in an uncertain environment. We measure fluid intelligence and study experimentally how individuals learn from observing the choices of a demonstrator in a 2-armed bandit problem with changing probabilities of a reward. Participants observe a demonstrator with high or low fluid intelligence. In some treatments they are aware of the intelligence score of the demonstrator and in others they are not. Low fluid intelligence individuals imitate the demonstrator more when her fluid intelligence is known than when it is not. Conversely, individuals with high fluid intelligence adjust their use of social information, as the observed behaviour changes, independently of the knowledge of the intelligence of the demonstrator. We provide evidence that intelligence determines how social and individual information is integrated in order to make choices in a changing uncertain environment.

Instructional Learning Objects in the Digital Classroom: Effectively Measuring Impact on Student Success

ERIC Educational Resources Information Center

Contrino, Jacline L.

2016-01-01

Demonstrating library impact on student success is critical for all academic libraries today. This article discusses how the library of a large online university serving non-traditional students evaluated how customized point-of-need learning objects (LOs) embedded in the learning management system impacted student learning. Using a comprehensive…

A Task-Based Language Teaching Approach to Developing Metacognitive Strategies for Listening Comprehension

ERIC Educational Resources Information Center

Chou, Mu-Hsuan

2017-01-01

In second (L2) or foreign language (FL) learning, learning strategies help learners perform tasks, solve specific problems, and compensate for learning deficits. Of the strategy types, metacognitive strategies manage and regulate the construction of L2 or FL knowledge. Although learning strategies are frequently taught via teacher demonstration,…

Beyond Performativity: A Pragmatic Model of Teacher Professional Learning

ERIC Educational Resources Information Center

Lloyd, Margaret; Davis, James P.

2018-01-01

The intent and content of teacher professional learning has changed in recent times to meet the demands of performativity. In this article, we offer and demonstrate a pragmatic way to map teacher professional learning that both meets current demands and secures a place for teacher-led catalytic learning. To achieve this, we position identified…

Can You Do It? How Preschoolers Judge Whether Others Have Learned

ERIC Educational Resources Information Center

Sobel, David M.

2015-01-01

Two experiments investigated how preschoolers judge whether learning has occurred. Experiment 1 showed that 3- and 4-year-olds used an individual's ability to demonstrate knowledge to judge whether he/she had learned something, regardless of that individual's claim about whether he/she had learned. Experiment 2 considered whether children…

The Contribution of Vocational Students' Learning Discipline, Motivation and Learning Results

ERIC Educational Resources Information Center

Yussi; Syaad; Purnomo

2017-01-01

A good vocational high school prepares students for developing capability of working independently, demonstrating professional attitude at work, and being productive which that require good learning results for the realization thereof. the learning results serve as the yardstick of students' success. The purpose of this article is to find out the…

The Effects of Scaffolded Simulation-Based Inquiry Learning on Fifth-Graders' Representations of the Greenhouse Effect

ERIC Educational Resources Information Center

Kukkonen, Jari Ensio; Kärkkäinen, Sirpa; Dillon, Patrick; Keinonen, Tuula

2014-01-01

Research has demonstrated that simulation-based inquiry learning has significant advantages for learning outcomes when properly scaffolded. For successful learning in science with simulation-based inquiry, one needs to ascertain levels of background knowledge so as to support learners in making, evaluating and modifying hypotheses, conducting…

Teaching to Learn: Analyzing the Experiences of First-Time Physics Learning Assistants

ERIC Educational Resources Information Center

Gray, Kara Elizabeth

2013-01-01

The Colorado Learning Assistant (LA) Model has demonstrated that it is successful in helping to meet multiple goals including enhancing student learning in LA-supported courses, increasing conceptual understanding of physics among LAs, and improving the teaching practices of former LAs in K-12 schools. The research reported here investigated the…

Teachers as Informal Learners: Workplace Professional Learning in the United States and Lithuania

ERIC Educational Resources Information Center

Jurasaite-Harbison, Elena; Rex, Lesley A.

2013-01-01

This study demonstrates the understandings that result from teachers' explanations of how they learn when they encounter everyday situations that evoke their learning. The study renders these explanations as a framework for further research on teacher workplace learning in informal settings. The framework emerged from a constant-comparative…

Original Science-Based Music and Student Learning

ERIC Educational Resources Information Center

Smolinski, Keith

2010-01-01

American middle school student science scores have been stagnating for several years, demonstrating a need for better learning strategies to aid teachers in instruction and students in content learning. It has also been suggested by researchers that music can be used to aid students in their learning and memory. Employing the theoretical framework…

Knowledge Creation and Innovation in a Civil Engineering Course for the First-Year University Students

ERIC Educational Resources Information Center

Salmisto, Alpo; Nokelainen, Petri

2015-01-01

This article examines the application of knowledge creation learning and innovation to higher education in construction. The objectives are to demonstrate the application of the course based on knowledge creation learning to mass teaching and to analyse whether knowledge creation learning improves student motivation and learning. The empirical…

In-Class Laptop Use and Its Effects on Student Learning

ERIC Educational Resources Information Center

Fried, Carrie B.

2008-01-01

Recently, a debate has begun over whether in-class laptops aid or hinder learning. While some research demonstrates that laptops can be an important learning tool, anecdotal evidence suggests more and more faculty are banning laptops from their classrooms because of perceptions that they distract students and detract from learning. The current…

Assessment of Online Discussion in Work-Integrated Learning

ERIC Educational Resources Information Center

McNamara, Judith; Brown, Catherine

2009-01-01

Purpose: The purpose of this paper is to examine how online discussion can be used in work-integrated learning as a vehicle for students to demonstrate their learning in the workplace and to facilitate collaborative learning where face-to-face classes are not feasible. Design/methodology/approach: The paper evaluates the use of assessable online…

101 Things to Learn in Art School

ERIC Educational Resources Information Center

White, Kit

2011-01-01

What is the first thing to learn in art school? "Art can be anything." The second thing? "Learn to draw." With "101 Things to Learn in Art School", artist and teacher Kit White delivers and develops such lessons, striking an instructive balance between technical advice and sage concepts. These 101 maxims, meditations, and demonstrations offer both…

Missing the Trees for the Forest?: Learning Environments versus Learning Techniques in Simulations

ERIC Educational Resources Information Center

Raymond, Chad

2012-01-01

Institutions of higher learning are increasingly asked to defend curricular and pedagogical outcomes. Faculty must demonstrate that simulations are productive tools for learning, but a review of the literature shows that the evidence of their effectiveness is inconclusive, despite their popularity in the classroom. Simulations may in fact help…

Evaluating the Impacts of Professional Development: A Mixed Method Study of Adult Education Learning Communities

ERIC Educational Resources Information Center

Dilworth, Jessica S.

2010-01-01

Adult education programs providing classes to students preparing for high school equivalency and learning English that demonstrate characteristics of learning organizations may be better able to thrive when confronted with less-than-ideal circumstances. Many of these programs organize adult educators into learning communities as the context for…

Computer-Based Enhancements for the Improvement of Learning.

ERIC Educational Resources Information Center

Tennyson, Robert D.

The third of four symposium papers argues that, if instructional methods are to improve learning, they must have two aspects: a direct trace to a specific learning process, and empirical support that demonstrates their significance. Focusing on the tracing process, the paper presents an information processing model of learning that can be used by…

An Analytic Framework to Support E.Learning Strategy Development

ERIC Educational Resources Information Center

Marshall, Stephen J.

2012-01-01

Purpose: The purpose of this paper is to discuss and demonstrate the relevance of a new conceptual framework for leading and managing the development of learning and teaching to e.learning strategy development. Design/methodology/approach: After reviewing and discussing the research literature on e.learning in higher education institutions from…

Case-Based Modeling for Learning: Socially Constructed Skill Development

ERIC Educational Resources Information Center

Lyons, Paul; Bandura, Randall P.

2018-01-01

Purpose: Grounded on components of experiential learning theory (ELT) and self-regulation of learning (SRL) theory, augmented by elements of action theory and script development, the purpose of this paper is to demonstrate the case-based modeling (CBM) instructional approach that stimulates learning in groups or teams. CBM is related to individual…

Investigating High School Students' Conceptualizations of the Biological Basis of Learning

ERIC Educational Resources Information Center

Fulop, Rebecca M.; Tanner, Kimberly D.

2012-01-01

Students go to school to learn. How much, however, do students understand about the biological basis of this everyday process? Blackwell et al. (1) demonstrated a correlation between education about learning and academic achievement. Yet there are few studies investigating high school students' conceptions of learning. In this mixed-methods…

Poorer Phonetic Perceivers Show Greater Benefit in Phonetic-Phonological Speech Learning

ERIC Educational Resources Information Center

Ingvalson, Erin M.; Barr, Allison M.; Wong, Patrick C. M.

2013-01-01

Purpose: Previous research has demonstrated that native English speakers can learn lexical tones in word context (pitch-to-word learning), to an extent. However, learning success depends on learners' pre-training sensitivity to pitch patterns. The aim of this study was to determine whether lexical pitch-pattern training given before lexical…

Teaching for Meaningful Learning: A Review of Research on Inquiry-Based and Cooperative Learning. Book Excerpt

ERIC Educational Resources Information Center

Barron, Brigid; Darling-Hammond, Linda

2008-01-01

The George Lucas Educational Foundation began in 1991 with an ambitious mission: to demonstrate how innovative learning environments in classrooms, supported by powerful new technologies, could revolutionize learning. As an organization founded by George Lucas, its members believed that the same benefits of technology that were transforming…

Integration of Learning: A Grounded Theory Analysis of College Students' Learning

ERIC Educational Resources Information Center

Barber, James P.

2012-01-01

This article presents a grounded theory of "integration of learning" among traditional aged college students, which is characterized by the demonstrated ability to link various skills and knowledge learned in a variety of contexts. The author analyzed 194 interviews with students at liberal arts colleges to investigate empirically the ways…

User Studies: Developing Learning Strategy Tool Software for Children.

ERIC Educational Resources Information Center

Fitzgerald, Gail E.; Koury, Kevin A.; Peng, Hsinyi

This paper is a report of user studies for developing learning strategy tool software for children. The prototype software demonstrated is designed for children with learning and behavioral disabilities. The tools consist of easy-to-use templates for creating organizational, memory, and learning approach guides for use in classrooms and at home.…

Seamless Support: Technology Enhanced Learning in Open Distance Learning at NWU

ERIC Educational Resources Information Center

Esterhuizen, Hennie

2015-01-01

Frantic attempts of investing in technology to demonstrate willingness to educate for the knowledge society may result in failure to address the real requirements. This paper presents the main features of a framework for integrating Technology Enhanced Learning in Open Distance Learning at North-West University, South Africa. Support towards…

Not Blogging, Drinking: Peer Learning, Sociality and Intercultural Learning in Study Abroad

ERIC Educational Resources Information Center

Tonkin, Kati; Bourgault du Coudray, Chantal

2016-01-01

Research into study abroad students' intercultural learning has demonstrated a need to provide pedagogical support before, during and after the study abroad experience. This article reports on the authors' efforts to support the in-country learning of Australian study abroad students through an online guided reflection exercise (blog) with a…

An Educational System for Learning Search Algorithms and Automatically Assessing Student Performance

ERIC Educational Resources Information Center

Grivokostopoulou, Foteini; Perikos, Isidoros; Hatzilygeroudis, Ioannis

2017-01-01

In this paper, first we present an educational system that assists students in learning and tutors in teaching search algorithms, an artificial intelligence topic. Learning is achieved through a wide range of learning activities. Algorithm visualizations demonstrate the operational functionality of algorithms according to the principles of active…

A Framework for Hierarchical Perception-Action Learning Utilizing Fuzzy Reasoning.

PubMed

Windridge, David; Felsberg, Michael; Shaukat, Affan

2013-02-01

Perception-action (P-A) learning is an approach to cognitive system building that seeks to reduce the complexity associated with conventional environment-representation/action-planning approaches. Instead, actions are directly mapped onto the perceptual transitions that they bring about, eliminating the need for intermediate representation and significantly reducing training requirements. We here set out a very general learning framework for cognitive systems in which online learning of the P-A mapping may be conducted within a symbolic processing context, so that complex contextual reasoning can influence the P-A mapping. In utilizing a variational calculus approach to define a suitable objective function, the P-A mapping can be treated as an online learning problem via gradient descent using partial derivatives. Our central theoretical result is to demonstrate top-down modulation of low-level perceptual confidences via the Jacobian of the higher levels of a subsumptive P-A hierarchy. Thus, the separation of the Jacobian as a multiplying factor between levels within the objective function naturally enables the integration of abstract symbolic manipulation in the form of fuzzy deductive logic into the P-A mapping learning. We experimentally demonstrate that the resulting framework achieves significantly better accuracy than using P-A learning without top-down modulation. We also demonstrate that it permits novel forms of context-dependent multilevel P-A mapping, applying the mechanism in the context of an intelligent driver assistance system.

Mechanisms of value-learning in the guidance of spatial attention.

PubMed

Anderson, Brian A; Kim, Haena

2018-05-11

The role of associative reward learning in the guidance of feature-based attention is well established. The extent to which reward learning can modulate spatial attention has been much more controversial. At least one demonstration of a persistent spatial attention bias following space-based associative reward learning has been reported. At the same time, multiple other experiments have been published failing to demonstrate enduring attentional biases towards locations at which a target, if found, yields high reward. This is in spite of evidence that participants use reward structures to inform their decisions where to search, leading some to suggest that, unlike feature-based attention, spatial attention may be impervious to the influence of learning from reward structures. Here, we demonstrate a robust bias towards regions of a scene that participants were previously rewarded for selecting. This spatial bias relies on representations that are anchored to the configuration of objects within a scene. The observed bias appears to be driven specifically by reinforcement learning, and can be observed with equal strength following non-reward corrective feedback. The time course of the bias is consistent with a transient shift of attention, rather than a strategic search pattern, and is evident in eye movement patterns during free viewing. Taken together, our findings reconcile previously conflicting reports and offer an integrative account of how learning from feedback shapes the spatial attention system. Copyright © 2018 Elsevier B.V. All rights reserved.

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.

Human-robot skills transfer interfaces for a flexible surgical robot.

PubMed

Calinon, Sylvain; Bruno, Danilo; Malekzadeh, Milad S; Nanayakkara, Thrishantha; Caldwell, Darwin G

2014-09-01

In minimally invasive surgery, tools go through narrow openings and manipulate soft organs to perform surgical tasks. There are limitations in current robot-assisted surgical systems due to the rigidity of robot tools. The aim of the STIFF-FLOP European project is to develop a soft robotic arm to perform surgical tasks. The flexibility of the robot allows the surgeon to move within organs to reach remote areas inside the body and perform challenging procedures in laparoscopy. This article addresses the problem of designing learning interfaces enabling the transfer of skills from human demonstration. Robot programming by demonstration encompasses a wide range of learning strategies, from simple mimicking of the demonstrator's actions to the higher level imitation of the underlying intent extracted from the demonstrations. By focusing on this last form, we study the problem of extracting an objective function explaining the demonstrations from an over-specified set of candidate reward functions, and using this information for self-refinement of the skill. In contrast to inverse reinforcement learning strategies that attempt to explain the observations with reward functions defined for the entire task (or a set of pre-defined reward profiles active for different parts of the task), the proposed approach is based on context-dependent reward-weighted learning, where the robot can learn the relevance of candidate objective functions with respect to the current phase of the task or encountered situation. The robot then exploits this information for skills refinement in the policy parameters space. The proposed approach is tested in simulation with a cutting task performed by the STIFF-FLOP flexible robot, using kinesthetic demonstrations from a Barrett WAM manipulator. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Social learning strategies and predation risk: minnows copy only when using private information would be costly

PubMed Central

Webster, M.M; Laland, K.N

2008-01-01

Animals can acquire information from the environment privately, by sampling it directly, or socially, through learning from others. Generally, private information is more accurate, but expensive to acquire, while social information is cheaper but less reliable. Accordingly, the ‘costly information hypothesis’ predicts that individuals will use private information when the costs associated with doing so are low, but that they should increasingly use social information as the costs of using private information rise. While consistent with considerable data, this theory has yet to be directly tested in a satisfactory manner. We tested this hypothesis by giving minnows (Phoxinus phoxinus) a choice between socially demonstrated and non-demonstrated prey patches under conditions of low, indirect and high simulated predation risk. Subjects had no experience (experiment 1) or prior private information that conflicted with the social information provided by the demonstrators (experiment 2). In both experiments, subjects spent more time in the demonstrated patch than in the non-demonstrated patch, and in experiment 1 made fewer switches between patches, when risk was high compared with when it was low. These findings are consistent with the predictions of the costly information hypothesis, and imply that minnows adopt a ‘copy-when-asocial-learning-is-costly’ learning strategy. PMID:18755676

The Development of Social Learning in Interactive and Observational Contexts

ERIC Educational Resources Information Center

Matheson, Heath; Moore, Chris; Akhtar, Nameera

2013-01-01

From the first year of life, imitative learning readily occurs in contexts where a demonstrator directly interacts with infants (i.e., "interactive contexts"), and at least by 18 months, imitation will also occur in third-party or observational contexts where infants witness a demonstration by another person that is not directed at them. However,…

The Tapioca Bomb: A Demonstration to Enhance Learning about Combustion and Chemical Safety

ERIC Educational Resources Information Center

Keeratichamroen, Wasana; Dechsri, Precharn; Panijpan, Bhinyo; Ruenwongsa, Pintip

2010-01-01

In any demonstration to students, producing light and sound usually ensures interest and can enhance understanding and retention of the concepts involved. A guided inquiry (Predict, Observe, Explain: POE) approach was used to involve the students actively in their learning about the explosive combustion of fine flour particles in air in the…

Title VI-G Catalogue of Child Service Demonstration Centers 1977-1978.

ERIC Educational Resources Information Center

Network of Innovative Schools, Inc., Andover, MA.

The guide includes a directory and description of services provided by the 30 federally funded child service Demonstration Centers (CSDC) for learning disabed students. A catalogue overview booklet reviews the history of P.L. 91-230, Title VI-G (Education of the Handicapped Act, 1970) and discusses the role of the National Learning Disabilities…

Students' Perceptions, Attitudes, and Incorporation of Demonstrations, Popular Media Videos, and Animations Concerning Chemical Reactions

ERIC Educational Resources Information Center

Schlosser, Sarah Elizabeth

2012-01-01

Students often struggle with learning complex chemistry concepts. In today's society with the advances in multimedia technology, educators have a variety of tools available to help students learn these concepts. These tools include demonstrations, videos in the popular media, and animations; referred to collectively as multimethods. With the…

Using a Virtual Class to Demonstrate Computer-Mediated Group Dynamics Concepts

ERIC Educational Resources Information Center

Franz, Timothy M.; Vicker, Lauren A.

2010-01-01

We report about an active learning demonstration designed to use a virtual class to present computer-mediated group communication course concepts to show that students can learn about these concepts in a virtual class. We designated 1 class period as a virtual rather than face-to-face class, when class members "attended" virtually using…

Introducing Innovative Approaches to Learning in Fluid Mechanics: A Case Study

ERIC Educational Resources Information Center

Gynnild, Vidar; Myrhaug, Dag; Pettersen, Bjornar

2007-01-01

The purpose of the current article is to examine the impact of laboratory demonstrations and computer visualizations on learning in a third-year fluid mechanics course at Norwegian University of Science and Technology (NTNU). As a first step, on entering the course, students were exposed to a laboratory demonstration focusing on the nature of…

Effectiveness of Demonstrations Supported by ICT Tools on Upper Secondary School Students' Attitudes towards the Learning of Physics

ERIC Educational Resources Information Center

Yap, Boon Chien; Chew, Charles

2014-01-01

This quantitative research study reports the effectiveness of demonstrations supported by appropriate information and communication technology (ICT) tools such as dataloggers, animations and video clips on upper secondary school students' attitudes towards the learning of physics. A sample of 94 secondary four express stream (age 16 years) and…

Second-Order Conditioning of Human Causal Learning

ERIC Educational Resources Information Center

Jara, Elvia; Vila, Javier; Maldonado, Antonio

2006-01-01

This article provides the first demonstration of a reliable second-order conditioning (SOC) effect in human causal learning tasks. It demonstrates the human ability to infer relationships between a cause and an effect that were never paired together during training. Experiments 1a and 1b showed a clear and reliable SOC effect, while Experiments 2a…

A Demonstration of Techniques in the Identification, Diagnosis, and Treatment of Children with Learning Disabilities. Final Report.

ERIC Educational Resources Information Center

Skokie School District 68, IL.

A Chicago suburban public school with approximately 450 children per grade level demonstrated a system-wide program for identification, diagnosis, and educational treatment of children with learning disabilities in grades 2 through 6. Children were judged to underachieve when achievement measures in language or mathematics fell more than 10% below…

A Blended Learning Approach to Teaching Project Management: A Model for Active Participation and Involvement--Insights from Norway

ERIC Educational Resources Information Center

Hussein, Bassam A.

2015-01-01

The paper demonstrates and evaluates the effectiveness of a blended learning approach to create a meaningful learning environment. We use the term blended learning approach in this paper to refer to the use of multiple or hybrid instructional methods that emphasize the role of learners as contributors to the learning process rather than recipients…

Creating Small Learning Communities: Lessons from the Project on High-Performing Learning Communities about "What Works" in Creating Productive, Developmentally Enhancing, Learning Contexts

ERIC Educational Resources Information Center

Felner, Robert D.; Seitsinger, Anne M.; Brand, Stephen; Burns, Amy; Bolton, Natalie

2007-01-01

Personalizing the school environment is a central goal of efforts to transform America's schools. Three decades of work by the Project on High Performance Learning Communities are considered that demonstrate the potential impact and importance of the creation of "small learning environments" on student motivation, adjustment, and well-being.…

Treatment of adolescent sexual offenders: theory-based practice.

PubMed

Sermabeikian, P; Martinez, D

1994-11-01

The treatment of adolescent sexual offenders (ASO) has its theoretical underpinnings in social learning theory. Although social learning theory has been frequently cited in literature, a comprehensive application of this theory, as applied to practice, has not been mapped out. The social learning and social cognitive theories of Bandura appear to be particularly relevant to the group treatment of this population. The application of these theories to practice, as demonstrated in a program model, is discussed as a means of demonstrating how theory-driven practice methods can be developed.

Action learning across the decades.

PubMed

Eason, Ken

2017-05-02

Purpose The purpose of this paper is to explore how action learning concepts were used in two healthcare projects undertaken many decades apart. The specific purpose in both cases was to examine how action learning can contribute to shared learning across key stakeholders in a complex socio-technical system. In each case study, action learning supported joint design programmes and the sharing of perspectives about the complex system under investigation. Design/methodology/approach Two action learning projects are described: first, the Hospital Internal Communications (HIC) project led by Reg Revans in the 1960s. Senior staff in ten London hospitals formed action learning teams to address communication issues. Second, in the Better Outcomes for People with Learning Disabilities: Transforming Care (BOLDTC) project, videoconferencing equipment enabled people with learning disabilities to increase their opportunities to communicate. A mutual learning process was established to enable stakeholders to explore the potential of the technical system to improve individual care. Findings The HIC project demonstrated the importance of evidence being shared between team members and that action had to engage the larger healthcare system outside the hospital. The BOLDTC project confirmed the continuing relevance of action learning to healthcare today. Mutual learning was achieved between health and social care specialists and technologists. Originality/value This work draws together the socio-technical systems tradition (considering both social and technical issues in organisations) and action learning to demonstrate that complex systems development needs to be undertaken as a learning process in which action provides the fuel for learning and design.

Imitation and Emulation by Dogs Using a Bidirectional Control Procedure

PubMed Central

Miller, Holly C.; Rayburn-Reeves, Rebecca; Zentall, Thomas R.

2009-01-01

A successful procedure for studying imitative behavior in non-humans is the bidirectional control procedure in which observers are exposed to a demonstrator that responds by moving a manipulandum in one of two different directions (e.g., left vs. right). Imitative learning is demonstrated when observers make the response in the direction that they observed it being made. This procedure controls for socially mediated effects (the mere presence of a demonstrator), stimulus enhancement (attention drawn to a manipulandum by its movement), and if an appropriate control is included, emulation (learning how the environment works). Recent research with dogs has found that dogs may not demonstrate imitative learning when the demonstrator is human. In the present research, we found that when odors were controlled for, dogs imitated the direction of a screen push demonstrated by another dog more than in a control condition in which they observed the screen move independently while another dog was present. Furthermore, we found that dogs would match the direction of screen push demonstrated by a human and they were equally likely to match the direction in which the screen moved independently while a human was present. PMID:18977419

Mere exposure alters category learning of novel objects.

PubMed

Folstein, Jonathan R; Gauthier, Isabel; Palmeri, Thomas J

2010-01-01

We investigated how mere exposure to complex objects with correlated or uncorrelated object features affects later category learning of new objects not seen during exposure. Correlations among pre-exposed object dimensions influenced later category learning. Unlike other published studies, the collection of pre-exposed objects provided no information regarding the categories to be learned, ruling out unsupervised or incidental category learning during pre-exposure. Instead, results are interpreted with respect to statistical learning mechanisms, providing one of the first demonstrations of how statistical learning can influence visual object learning.

Mere Exposure Alters Category Learning of Novel Objects

PubMed Central

Folstein, Jonathan R.; Gauthier, Isabel; Palmeri, Thomas J.

2010-01-01

We investigated how mere exposure to complex objects with correlated or uncorrelated object features affects later category learning of new objects not seen during exposure. Correlations among pre-exposed object dimensions influenced later category learning. Unlike other published studies, the collection of pre-exposed objects provided no information regarding the categories to be learned, ruling out unsupervised or incidental category learning during pre-exposure. Instead, results are interpreted with respect to statistical learning mechanisms, providing one of the first demonstrations of how statistical learning can influence visual object learning. PMID:21833209

Electronic Learning in Yugoslavia.

ERIC Educational Resources Information Center

Barker, Philip G.

1990-01-01

Describes a course taught at the University of Zagreb (Yugoslavia) on electronic learning methods based upon computer-assisted learning techniques. The course content is outlined, including lectures, workshops, videotapes, demonstration software, and courseware authoring; a multimedia teaching laboratory is described; and an evaluation of course…

Competition between multiple words for a referent in cross-situational word learning

PubMed Central

Benitez, Viridiana L.; Yurovsky, Daniel; Smith, Linda B.

2016-01-01

Three experiments investigated competition between word-object pairings in a cross-situational word-learning paradigm. Adults were presented with One-Word pairings, where a single word labeled a single object, and Two-Word pairings, where two words labeled a single object. In addition to measuring learning of these two pairing types, we measured competition between words that refer to the same object. When the word-object co-occurrences were presented intermixed in training (Experiment 1), we found evidence for direct competition between words that label the same referent. Separating the two words for an object in time eliminated any evidence for this competition (Experiment 2). Experiment 3 demonstrated that adding a linguistic cue to the second label for a referent led to different competition effects between adults who self-reported different language learning histories, suggesting both distinctiveness and language learning history affect competition. Finally, in all experiments, competition effects were unrelated to participants’ explicit judgments of learning, suggesting that competition reflects the operating characteristics of implicit learning processes. Together, these results demonstrate that the role of competition between overlapping associations in statistical word-referent learning depends on time, the distinctiveness of word-object pairings, and language learning history. PMID:27087742

Machine learning enhanced optical distance sensor

NASA Astrophysics Data System (ADS)

Amin, M. Junaid; Riza, N. A.

2018-01-01

Presented for the first time is a machine learning enhanced optical distance sensor. The distance sensor is based on our previously demonstrated distance measurement technique that uses an Electronically Controlled Variable Focus Lens (ECVFL) with a laser source to illuminate a target plane with a controlled optical beam spot. This spot with varying spot sizes is viewed by an off-axis camera and the spot size data is processed to compute the distance. In particular, proposed and demonstrated in this paper is the use of a regularized polynomial regression based supervised machine learning algorithm to enhance the accuracy of the operational sensor. The algorithm uses the acquired features and corresponding labels that are the actual target distance values to train a machine learning model. The optimized training model is trained over a 1000 mm (or 1 m) experimental target distance range. Using the machine learning algorithm produces a training set and testing set distance measurement errors of <0.8 mm and <2.2 mm, respectively. The test measurement error is at least a factor of 4 improvement over our prior sensor demonstration without the use of machine learning. Applications for the proposed sensor include industrial scenario distance sensing where target material specific training models can be generated to realize low <1% measurement error distance measurements.

Reward-Modulated Hebbian Plasticity as Leverage for Partially Embodied Control in Compliant Robotics

PubMed Central

Burms, Jeroen; Caluwaerts, Ken; Dambre, Joni

2015-01-01

In embodied computation (or morphological computation), part of the complexity of motor control is offloaded to the body dynamics. We demonstrate that a simple Hebbian-like learning rule can be used to train systems with (partial) embodiment, and can be extended outside of the scope of traditional neural networks. To this end, we apply the learning rule to optimize the connection weights of recurrent neural networks with different topologies and for various tasks. We then apply this learning rule to a simulated compliant tensegrity robot by optimizing static feedback controllers that directly exploit the dynamics of the robot body. This leads to partially embodied controllers, i.e., hybrid controllers that naturally integrate the computations that are performed by the robot body into a neural network architecture. Our results demonstrate the universal applicability of reward-modulated Hebbian learning. Furthermore, they demonstrate the robustness of systems trained with the learning rule. This study strengthens our belief that compliant robots should or can be seen as computational units, instead of dumb hardware that needs a complex controller. This link between compliant robotics and neural networks is also the main reason for our search for simple universal learning rules for both neural networks and robotics. PMID:26347645

The practical epistemologies of the classroom: A study of laboratory work

NASA Astrophysics Data System (ADS)

Wickman, Per-Olof

2004-05-01

The practical epistemologies of university students during laboratory work in chemistry are analyzed to enhance understanding of how teaching practices interact with learners. The purpose is to develop a theoretical framework of learning as action that can be used by educational researchers to examine meaning-making, but also by teachers in close association with their daily work to understand the course learning takes in their own classrooms. Here this framework is adopted to demonstrate how the sequence of learning may affect the subject content learnt. It is also demonstrated how learning can be understood in terms of habits, and how observations of such habits could be used by a teacher to inform her/his teaching. The theory of practical epistemologies is based on the later Wittgenstein, pragmatics, and sociocultural approaches identifying learning with talk, action, and habits situated in practices.

A low-cost approach for rapidly creating demonstration models for hands-on learning

NASA Astrophysics Data System (ADS)

Kinzli, Kristoph-Dietrich; Kunberger, Tanya; O'Neill, Robert; Badir, Ashraf

2018-01-01

Demonstration models allow students to readily grasp theory and relate difficult concepts and equations to real life. However drawbacks of using these demonstration models are that they are can be costly to purchase from vendors or take a significant amount of time to build. These two limiting factors can pose a significant obstacle for adding demonstrations to the curriculum. This article presents an assignment to overcome these obstacles, which has resulted in 36 demonstration models being added to the curriculum. The article also presents the results of student performance on course objectives as a result of the developed models being used in the classroom. Overall, significant improvement in student learning outcomes, due to the addition of demonstration models, has been observed.

Contingency learning deficits and generalization in chronic unilateral hand pain patients.

PubMed

Meulders, Ann; Harvie, Daniel S; Bowering, Jane K; Caragianis, Suzanne; Vlaeyen, Johan W S; Moseley, G Lorimer

2014-10-01

Contingency learning, in particular the formation of danger beliefs, underpins conditioned fear and avoidance behavior, yet equally important is the formation of safety beliefs. That is, when threat beliefs and accompanying fear/avoidance spread to technically safe cues, it might cause disability. Indeed, such over generalization has been advanced as a trans-diagnostic pathologic marker, but it has not been investigated in chronic pain. Using a novel hand pain scenario contingency learning task, we tested the hypotheses that chronic hand pain patients demonstrate less differential pain expectancy judgments because of poor safety learning and demonstrate broader generalization gradients than healthy controls. Participants viewed digitized 3-dimensional hands in different postures presented in random order (conditioned stimulus [CS]) and rated the likelihood that a fictive patient would feel pain when moving the hand into that posture. Subsequently, the outcome (pain/no pain) was presented on the screen. One hand posture was followed by pain (CS+), another was not (CS-). Generalization was tested using novel hand postures (generalization stimuli) that varied in how similar they were to the original conditioned stimuli. Patients, but not healthy controls, demonstrated a contingency learning deficit determined by impaired safety learning, but not by exaggerated pain expectancy toward the CS+. Patients showed flatter, asymmetric generalization gradients than the healthy controls did, with higher pain expectancy for novel postures that were more similar to the original CS-. The results clearly uphold our hypotheses and suggest that contingency learning deficits might be important in the development and maintenance of the chronic pain-related disability. Chronic hand pain patients demonstrate 1) reduced differential contingency learning determined by a lack of safety belief formation, but not by exaggerated threat belief formation, and 2) flatter, asymmetric generalization gradients than the healthy controls. Copyright © 2014 American Pain Society. Published by Elsevier Inc. All rights reserved.

Understanding the Context of Learning in an Online Social Network for Health Professionals' Informal Learning.

PubMed

Li, Xin; Gray, Kathleen; Verspoor, Karin; Barnett, Stephen

2017-01-01

Online social networks (OSN) enable health professionals to learn informally, for example by sharing medical knowledge, or discussing practice management challenges and clinical issues. Understanding the learning context in OSN is necessary to get a complete picture of the learning process, in order to better support this type of learning. This study proposes critical contextual factors for understanding the learning context in OSN for health professionals, and demonstrates how these contextual factors can be used to analyse the learning context in a designated online learning environment for health professionals.

A network model of behavioural performance in a rule learning task.

PubMed

Hasselmo, Michael E; Stern, Chantal E

2018-04-19

Humans demonstrate differences in performance on cognitive rule learning tasks which could involve differences in properties of neural circuits. An example model is presented to show how gating of the spread of neural activity could underlie rule learning and the generalization of rules to previously unseen stimuli. This model uses the activity of gating units to regulate the pattern of connectivity between neurons responding to sensory input and subsequent gating units or output units. This model allows analysis of network parameters that could contribute to differences in cognitive rule learning. These network parameters include differences in the parameters of synaptic modification and presynaptic inhibition of synaptic transmission that could be regulated by neuromodulatory influences on neural circuits. Neuromodulatory receptors play an important role in cognitive function, as demonstrated by the fact that drugs that block cholinergic muscarinic receptors can cause cognitive impairments. In discussions of the links between neuromodulatory systems and biologically based traits, the issue of mechanisms through which these linkages are realized is often missing. This model demonstrates potential roles of neural circuit parameters regulated by acetylcholine in learning context-dependent rules, and demonstrates the potential contribution of variation in neural circuit properties and neuromodulatory function to individual differences in cognitive function.This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'. © 2018 The Author(s).

Expression of HIV-Tat protein is associated with learning and memory deficits in the mouse

PubMed Central

Carey, Amanda N.; Sypek, Elizabeth I.; Singh, Harminder D.; Kaufman, Marc J.; McLaughlin, Jay P.

2012-01-01

HIV-Tat protein has been implicated in the pathogenesis of HIV-1 neurological complications (i.e., neuroAIDS), but direct demonstrations of the effects of Tat on behavior are limited. GT-tg mice with a doxycycline (Dox)-inducible and brain-selective tat gene coding for Tat protein were used to test the hypothesis that the activity of Tat in brain is sufficient to impair learning and memory processes. Western blot analysis of GT-tg mouse brains demonstrated an increase in Tat antibody labeling that seemed to be dependent on the dose and duration of Dox pretreatment. Dox-treated GT-tg mice tested in the Barnes maze demonstrated longer latencies to find an escape hole and displayed deficits in probe trial performance, versus uninduced GT-tg littermates, suggesting Tat-induced impairments of spatial learning and memory. Reversal learning was also impaired in Tat-induced mice. Tat-induced mice additionally demonstrated long-lasting (up to one month) deficiencies in novel object recognition learning and memory performance. Furthermore, novel object recognition impairment was dependent on the dose and duration of Dox exposure, suggesting that Tat exposure progressively mediated deficits. These experiments provide evidence that Tat protein expression is sufficient to mediate cognitive abnormalities seen in HIV-infected individuals. Moreover, the genetically engineered GT-tg mouse may be useful for improving our understanding of the neurological underpinnings of neuroAIDS-related behaviors. PMID:22197678

The Comparison of Solitary and Collaborative Modes of Game-Based Learning on Students' Science Learning and Motivation

ERIC Educational Resources Information Center

Chen, Ching-Huei; Wang, Kuan-Chieh; Lin, Yu-Hsuan

2015-01-01

In this study, we investigated and compared solitary and collaborative modes of game-based learning in promoting students' science learning and motivation. A total of fifty seventh grade students participated in this study. The results showed that students who played in a solitary or collaborative mode demonstrated improvement in learning…

Attitudes to Formal Business Training and Learning amongst Entrepreneurs in the Cultural Industries: Situated Business Learning through "Doing with Others."

ERIC Educational Resources Information Center

Raffo, Carlo; O'Connor, Justin; Lovatt, Andy; Banks, Mark

2000-01-01

Presents arguments supporting a social model of learning linked to situated learning and cultural capital. Critiques training methods used in cultural industries (arts, publishing, broadcasting, design, fashion, restaurants). Uses case study evidence to demonstrates inadequacies of formal training in this sector. (Contains 49 references.) (SK)

Culturally Sensitive Transformational Learning: Incorporating the Afrocentric Paradigm and African Feminism

ERIC Educational Resources Information Center

Ntseane, Peggy Gabo

2011-01-01

Informed by the Afrocentric learning paradigm, this conceptual piece argues that Mezirow's version of the theory of transformative learning is useful, but it would be more so if applied to be culturally sensitive. Using Botswana cultural learning values as an example, the article demonstrates how the theory can be made culturally sensitive to an…

The Influence of Collaborative Learning Games within Different Devices on Student's Learning Performance and Behaviours

ERIC Educational Resources Information Center

Hsiao, Hsien-Sheng; Chang, Cheng-Sian; Lin, Chien-Yu; Chang, Chih-Chun; Chen, Jyun-Chen

2014-01-01

This study demonstrates the effectiveness of using multi-touch tabletop collaborative game (MTCG) as a collaborative learning platform, in which multiple students can play games using a digital surface. The learning performance of participants is also explored, along with their related behaviours and their experiences. Consisting of 49 Taipei…

Teachable Agents and the Protege Effect: Increasing the Effort towards Learning

ERIC Educational Resources Information Center

Chase, Catherine C.; Chin, Doris B.; Oppezzo, Marily A.; Schwartz, Daniel L.

2009-01-01

Betty's Brain is a computer-based learning environment that capitalizes on the social aspects of learning. In Betty's Brain, students instruct a character called a Teachable Agent (TA) which can reason based on how it is taught. Two studies demonstrate the "protege effect": students make greater effort to learn for their TAs than they do…

The Impact of Altered Realities: Implications of Online Delivery for Learners' Interactions, Expectations, and Learning Skills

ERIC Educational Resources Information Center

Reisetter, Marcy; LaPointe, Loralee; Korcuska, James

2007-01-01

Although research consistently demonstrates that students learn content in online classes as well as their campus based counterparts and are equally satisfied with the quality of their learning, more information is needed that describes how the learning experiences themselves may vary. A traditional group of students was compared with an online…

Blogs as a Representation of Student Experiences in a Service Learning Course

ERIC Educational Resources Information Center

Gerstenblatt, Paula

2014-01-01

Research on service learning has demonstrated positive outcomes in several areas of student learning; however, there is a scarcity of research examining the lived experiences of students. This study consisted of seventeen students from two cohorts enrolled in a service learning class working in a rural town. The current study suggests the…

A Practice-Based Approach to Student Reflection in the Workplace during a Work-Integrated Learning Placement

ERIC Educational Resources Information Center

Sykes, Christopher; Dean, Bonnie Amelia

2013-01-01

In the Work-Integrated Learning (WIL) curriculum, reflection on workplace activities is widely used to support student learning. Recent critiques have demonstrated the limitations of current approaches to support students' reflective learning of workplace practices. By employing a practice-based approach, we seek to refocus WIL reflection on…

Student Access to Online Interaction Technologies: The Impact on Grade Delta Variance and Student Satisfaction

ERIC Educational Resources Information Center

Revels, Mark; Ciampa, Mark

2012-01-01

Online learning has significantly changed the educational landscape in recent years, offering advantages to both schools as well as students. Despite the fact that some faculty members are not supportive of online learning, researchers have demonstrated that the quality of online learning to be as effective as classroom learning. It has been…

Inquiry Learning: Level, Discipline, Class Size, What Matters?

ERIC Educational Resources Information Center

Vajoczki, Susan; Watt, Susan; Vine, Michelle M.; Liao, Xueqing

2011-01-01

Inquiry learning is a pedagogical approach that focuses on the processes and skills required to conduct research. It is a pedagogical approach that has been demonstrated to have positive learning outcomes. McMaster University has been committed to this form of learning for more than ten years in three of the faculties on campus (i.e., Humanities,…

Learning against the Clock: Examining Learning and Development Concepts in "The Curious Case of Benjamin Button"

ERIC Educational Resources Information Center

Koenig, Allison L.; Smith, Amber R.

2013-01-01

Media and popular culture reach broad audiences and have the potential to be an invaluable teaching resource in terms of promoting adult education and learning. Human resource development instructors can use media artifacts (e.g., films, television, novels, and cartoons) as useful methods to demonstrate learning theory and adult development…

Training with Differential Outcomes Enhances Discriminative Learning and Visuospatial Recognition Memory in Children Born Prematurely

ERIC Educational Resources Information Center

Martinez, Lourdes; Mari-Beffa, Paloma; Roldan-Tapia, Dolores; Ramos-Lizana, Julio; Fuentes, Luis J.; Estevez, Angeles F.

2012-01-01

Previous studies have demonstrated that discriminative learning is facilitated when a particular outcome is associated with each relation to be learned. When this training procedure is applied (the differential outcome procedure; DOP), learning is faster and more accurate than when the more common non-differential outcome procedure is used. This…

Learning and Teaching Styles in Management Education: Identifying, Analyzing, and Facilitating

ERIC Educational Resources Information Center

Provitera, Michael J.; Esendal, Esin

2008-01-01

Drawing on the learning theory of the Felder-Silverman model (2002), and the work of A.F. Grasha, this paper provides a brief review of teaching and learning styles used in management education. Professors, like students, demonstrate a number of learning styles and a professor has some responsibility to organize and present a course to satisfy…

Learning By Serving: 2,000 Ideas for Service-Learning Projects. Hot Topics: Usable Research.

ERIC Educational Resources Information Center

Follman, Joseph; And Others

Defining service learning as the formal integration of public service into student instruction and learning, this guide provides teachers with ideas for narrowing the gap between what students do in school and what they will do after they leave school. The example activities, derived from actual projects, demonstrate the nearly limitless range of…

Business Students' Learning with Online Discussion Forums: The Case of a Virtual Classroom Community

ERIC Educational Resources Information Center

Zhu, Jake

2010-01-01

This study examined what learning is and how learning was facilitated in a virtual classroom community using online discussion forums. Results demonstrated that learning in such a community was the active participation by the members of the community in the process of meaning construction. The construction of meaning in such a community was…

Learned Attention in Adult Language Acquisition: A Replication and Generalization Study and Meta-Analysis

ERIC Educational Resources Information Center

Ellis, Nick C.; Sagarra, Nuria

2011-01-01

This study investigates associative learning explanations of the limited attainment of adult compared to child language acquisition in terms of learned attention to cues. It replicates and extends Ellis and Sagarra (2010) in demonstrating short- and long-term learned attention in the acquisition of temporal reference in Latin. In Experiment 1,…

Learn with the Classics: Using Music To Study Smart at Any Age.

ERIC Educational Resources Information Center

Andersen, Ole; Marsh, Marcy; Harvey, Arthur

This book, accompanied by a musical CD-ROM, provides information on how to enhance learning through music at any age. Sections include: (1) "Let Music Prime Your Brain For Learning," which teaches how important it is to prime the brain for learning through music; (2) "Study Smart," which demonstrates highly effective studying techniques devised by…

Building Bridges: Seeking Structure and Direction for Higher Education Motivated Learning Strategy Models

ERIC Educational Resources Information Center

Fryer, Luke K.

2017-01-01

Many of our current higher education (HE) learning strategy models intersect at important points. At the same time, these theories also often demonstrate important unique perspectives on student learning within HE. Currently, research with one learning strategy model rarely leads to developments in others, as each group of researchers works in…

ESL Teaching and Learning Styles at the University of the Americas, Puebla, Mexico.

ERIC Educational Resources Information Center

Bauder, Thomas A.; Milman, Jacquelyn

A summary is presented of research on learning and teaching styles in English as a Second Language, and of results of learning and teaching style preference surveys conducted at a Mexican university in 1989. The students surveyed demonstrated much more cognitive flexibility or willingness to learn through different cognitive modes than was…

Reviewing Research on Mobile Learning in K-12 Educational Settings: Implications for Students with Disabilities

ERIC Educational Resources Information Center

Xie, Jingrong; Basham, James D.; Marino, Matthew T.; Rice, Mary F.

2018-01-01

Mobile technologies have shown great potential in various educational settings. Moreover, there is an emerging research base demonstrating how students view and interact with mobile devices to learn. As more of these technologies enter inclusive educational settings, an understanding of the extant research base for mobile learning (M-learning) and…

A Planning Tool for Incorporating Backward Design, Active Learning, and Authentic Assessment in the College Classroom

ERIC Educational Resources Information Center

Reynolds, Heather L.; Kearns, Katherine Dowell

2017-01-01

Backward course design is a compelling strategy for achieving results-based, student-centered learning. The backward course-design approach is first to identify student-learning outcomes, then the means of assessing the outcomes, and lastly the classroom activities that would support the learning outcomes. With demonstrated success at improving…

Stimulating Multiple-Demand Cortex Enhances Vocabulary Learning

PubMed Central

Wise, Richard J.S.; Geranmayeh, Fatemeh; Hampshire, Adam

2017-01-01

It is well established that networks within multiple-demand cortex (MDC) become active when diverse skills and behaviors are being learnt. However, their causal role in learning remains to be established. In the present study, we first performed functional magnetic resonance imaging on healthy female and male human participants to confirm that MDC was most active in the initial stages of learning a novel vocabulary, consisting of pronounceable nonwords (pseudowords), each associated with a picture of a real object. We then examined, in healthy female and male human participants, whether repetitive transcranial magnetic stimulation of a frontal midline node of the cingulo-opercular MDC affected learning rates specifically during the initial stages of learning. We report that stimulation of this node, but not a control brain region, substantially improved both accuracy and response times during the earliest stage of learning pseudoword–object associations. This stimulation had no effect on the processing of established vocabulary, tested by the accuracy and response times when participants decided whether a real word was accurately paired with a picture of an object. These results provide evidence that noninvasive stimulation to MDC nodes can enhance learning rates, thereby demonstrating their causal role in the learning process. We propose that this causal role makes MDC candidate target for experimental therapeutics; for example, in stroke patients with aphasia attempting to reacquire a vocabulary. SIGNIFICANCE STATEMENT Learning a task involves the brain system within which that specific task becomes established. Therefore, successfully learning a new vocabulary establishes the novel words in the language system. However, there is evidence that in the early stages of learning, networks within multiple-demand cortex (MDC), which control higher cognitive functions, such as working memory, attention, and monitoring of performance, become active. This activity declines once the task is learnt. The present study demonstrated that a node within MDC, located in midline frontal cortex, becomes active during the early stage of learning a novel vocabulary. Importantly, noninvasive brain stimulation of this node improved performance during this stage of learning. This observation demonstrated that MDC activity is important for learning. PMID:28676576

Career Issues in Organizations.

ERIC Educational Resources Information Center

1997

This document contains four papers from a symposium on career issues in organizations. "Learning During Downsizing: Stories from the Survivors" (Sharon J. Confessore) describes a study to demonstrate that survivors of corporate downsizings undertake learning activities and use many resources to accomplish the learning tasks.…

The MVP Model as an Organizing Framework for Neuroscience Findings Related to Learning

ERIC Educational Resources Information Center

Zakrajsek, Todd M.

2017-01-01

This chapter describes the ways in which the MVP model relates to recent research on neuroscience and learning, and demonstrates how those relationships may be used to better understand physiological impacts on motivation, and to facilitate improved learning.

The cost of selective attention in category learning: developmental differences between adults and infants.

PubMed

Best, Catherine A; Yim, Hyungwook; Sloutsky, Vladimir M

2013-10-01

Selective attention plays an important role in category learning. However, immaturities of top-down attentional control during infancy coupled with successful category learning suggest that early category learning is achieved without attending selectively. Research presented here examines this possibility by focusing on category learning in infants (6-8months old) and adults. Participants were trained on a novel visual category. Halfway through the experiment, unbeknownst to participants, the to-be-learned category switched to another category, where previously relevant features became irrelevant and previously irrelevant features became relevant. If participants attend selectively to the relevant features of the first category, they should incur a cost of selective attention immediately after the unknown category switch. Results revealed that adults demonstrated a cost, as evidenced by a decrease in accuracy and response time on test trials as well as a decrease in visual attention to newly relevant features. In contrast, infants did not demonstrate a similar cost of selective attention as adults despite evidence of learning both to-be-learned categories. Findings are discussed as supporting multiple systems of category learning and as suggesting that learning mechanisms engaged by adults may be different from those engaged by infants. Copyright © 2013 Elsevier Inc. All rights reserved.

WE-AB-206-03: Workshop

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

Lu, Z.

The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. The goal of this ultrasound hands-on workshop is to demonstrate quality control (QC) testing in diagnostic ultrasound and to provide updates in ACR ultrasound accreditation requirements. The first half of this workshop will include two presentations reviewing diagnostic ultrasound QA/QC and ACR ultrasound accreditation requirements. The second half of the workshop will include live demonstrations of basic QC tests. An array of ultrasound testing phantoms and ultrasound scanners will be available for attendees to learn diagnostic ultrasound QC in a hands-on environmentmore » with live demonstrations and on-site instructors. The targeted attendees are medical physicists in diagnostic imaging. Learning Objectives: Gain familiarity with common elements of a QA/QC program for diagnostic ultrasound imaging dentify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools Learn ACR ultrasound accreditation requirements Jennifer Walter is an employee of American College of Radiology on Ultrasound Accreditation.« less

WE-AB-206-01: Diagnostic Ultrasound Imaging Quality Assurance

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

Zagzebski, J.

The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. The goal of this ultrasound hands-on workshop is to demonstrate quality control (QC) testing in diagnostic ultrasound and to provide updates in ACR ultrasound accreditation requirements. The first half of this workshop will include two presentations reviewing diagnostic ultrasound QA/QC and ACR ultrasound accreditation requirements. The second half of the workshop will include live demonstrations of basic QC tests. An array of ultrasound testing phantoms and ultrasound scanners will be available for attendees to learn diagnostic ultrasound QC in a hands-on environmentmore » with live demonstrations and on-site instructors. The targeted attendees are medical physicists in diagnostic imaging. Learning Objectives: Gain familiarity with common elements of a QA/QC program for diagnostic ultrasound imaging dentify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools Learn ACR ultrasound accreditation requirements Jennifer Walter is an employee of American College of Radiology on Ultrasound Accreditation.« less

Combining Learning and Assessment in Assessment-Based Gaming Environments: A Case Study from a New York City School

ERIC Educational Resources Information Center

Zapata-Rivera, Diego; VanWinkle, Waverely; Doyle, Bryan; Buteux, Alyssa; Bauer, Malcolm

2009-01-01

Purpose: The purpose of this paper is to propose and demonstrate an evidence-based scenario design framework for assessment-based computer games. Design/methodology/approach: The evidence-based scenario design framework is presented and demonstrated by using BELLA, a new assessment-based gaming environment aimed at supporting student learning of…

Development of a Team-Based On-Farm Learning Program While Challenging Soybean Growers to Increase Yield

ERIC Educational Resources Information Center

Davis, Vince M.; Kull, Linda S.; Nelson, James A.

2012-01-01

Illinois soybean growers have not been satisfied with recent lagging yield trends. A yield "challenge" was created to blend the motivation and creativity of a yield contest with the learning power of teamwork and on-farm demonstration. In the initial year (2010), 123 on-farm side-by-side demonstration plots were located throughout the…

The impact of video technology on learning: A cooking skills experiment.

PubMed

Surgenor, Dawn; Hollywood, Lynsey; Furey, Sinéad; Lavelle, Fiona; McGowan, Laura; Spence, Michelle; Raats, Monique; McCloat, Amanda; Mooney, Elaine; Caraher, Martin; Dean, Moira

2017-07-01

This study examines the role of video technology in the development of cooking skills. The study explored the views of 141 female participants on whether video technology can promote confidence in learning new cooking skills to assist in meal preparation. Prior to each focus group participants took part in a cooking experiment to assess the most effective method of learning for low-skilled cooks across four experimental conditions (recipe card only; recipe card plus video demonstration; recipe card plus video demonstration conducted in segmented stages; and recipe card plus video demonstration whereby participants freely accessed video demonstrations as and when needed). Focus group findings revealed that video technology was perceived to assist learning in the cooking process in the following ways: (1) improved comprehension of the cooking process; (2) real-time reassurance in the cooking process; (3) assisting the acquisition of new cooking skills; and (4) enhancing the enjoyment of the cooking process. These findings display the potential for video technology to promote motivation and confidence as well as enhancing cooking skills among low-skilled individuals wishing to cook from scratch using fresh ingredients. Copyright © 2017 Elsevier Ltd. All rights reserved.

Social learning in juvenile lemon sharks, Negaprion brevirostris.

PubMed

Guttridge, Tristan L; van Dijk, Sander; Stamhuis, Eize J; Krause, Jens; Gruber, Samuel H; Brown, Culum

2013-01-01

Social learning is taxonomically widespread and can provide distinct behavioural advantages, such as in finding food or avoiding predators more efficiently. Although extensively studied in bony fishes, no such empirical evidence exists for cartilaginous fishes. Our aim in this study was to experimentally investigate the social learning capabilities of juvenile lemon sharks, Negaprion brevirostris. We designed a novel food task, where sharks were required to enter a start zone and subsequently make physical contact with a target in order to receive a food reward. Naive sharks were then able to interact with and observe (a) pre-trained sharks, that is, 'demonstrators', or (b) sharks with no previous experience, that is, 'sham demonstrators'. On completion, observer sharks were then isolated and tested individually in a similar task. During the exposure phase observers paired with 'demonstrator' sharks performed a greater number of task-related behaviours and made significantly more transitions from the start zone to the target, than observers paired with 'sham demonstrators'. When tested in isolation, observers previously paired with 'demonstrator' sharks completed a greater number of trials and made contact with the target significantly more often than observers previously paired with 'sham demonstrators'. Such experience also tended to result in faster overall task performance. These results indicate that juvenile lemon sharks, like numerous other animals, are capable of using socially derived information to learn about novel features in their environment. The results likely have important implications for behavioural processes, ecotourism and fisheries.

Creative group performances to assess core competencies in a first-year patient-centered medicine course

PubMed Central

Terregino, Carol A.; Saks, Norma S.

2010-01-01

Introduction A novel assessment of systems-based practice and practice-based learning and improvement learning objectives, implemented in a first-year patient-centered medicine course, is qualitatively described. Methods Student learning communities were asked to creatively demonstrate a problem and solution for health care delivery. Skits, filmed performances, plays, and documentaries were chosen by the students. Video recordings were reviewed for themes and the presence of course competencies. Results All performances demonstrated not only the index competencies of team work and facilitation of the learning of others, but many other core objectives of the course. The assignment was rated positively both by the faculty and the students, and has been added to the assessment modalities of the course. PMID:20174597

Creative group performances to assess core competencies in a first-year patient-centered medicine course.

PubMed

Terregino, Carol A; Saks, Norma S

2010-02-15

A novel assessment of systems-based practice and practice-based learning and improvement learning objectives, implemented in a first-year patient-centered medicine course, is qualitatively described. Student learning communities were asked to creatively demonstrate a problem and solution for health care delivery. Skits, filmed performances, plays, and documentaries were chosen by the students. Video recordings were reviewed for themes and the presence of course competencies. All performances demonstrated not only the index competencies of team work and facilitation of the learning of others, but many other core objectives of the course. The assignment was rated positively both by the faculty and the students, and has been added to the assessment modalities of the course.

Unsupervised learning in probabilistic neural networks with multi-state metal-oxide memristive synapses

NASA Astrophysics Data System (ADS)

Serb, Alexander; Bill, Johannes; Khiat, Ali; Berdan, Radu; Legenstein, Robert; Prodromakis, Themis

2016-09-01

In an increasingly data-rich world the need for developing computing systems that cannot only process, but ideally also interpret big data is becoming continuously more pressing. Brain-inspired concepts have shown great promise towards addressing this need. Here we demonstrate unsupervised learning in a probabilistic neural network that utilizes metal-oxide memristive devices as multi-state synapses. Our approach can be exploited for processing unlabelled data and can adapt to time-varying clusters that underlie incoming data by supporting the capability of reversible unsupervised learning. The potential of this work is showcased through the demonstration of successful learning in the presence of corrupted input data and probabilistic neurons, thus paving the way towards robust big-data processors.

Context-Dependent Learning in People With Parkinson's Disease.

PubMed

Lee, Ya-Yun; Winstein, Carolee J; Gordon, James; Petzinger, Giselle M; Zelinski, Elizabeth M; Fisher, Beth E

2016-01-01

Context-dependent learning is a phenomenon in which people demonstrate superior performance in the context in which they originally learned a skill but perform less well in a novel context. This study investigated context-dependent learning in people with Parkinson's disease (PD) and age-matched nondisabled adults. All participants practiced 3 finger sequences, each embedded within a unique context (colors and locations on a computer screen). One day after practice, the participants were tested either under the sequence-context associations remained the same as during practice, or the sequence-context associations were changed (SWITCH). Compared with nondisabled adults, people with PD demonstrated significantly greater decrement in performance (especially movement time) under the SWITCH condition, suggesting that individuals with PD are more context dependent than nondisabled adults.

Circles of Learning: Applying Socratic Pedagogy to Learn Modern Leadership

ERIC Educational Resources Information Center

Friesen, Katherine L.; Stephens, Clinton M.

2016-01-01

In response to the National Leadership Education Agenda, this application brief furthers priority one, addressing the teaching, learning, and curriculum development of leadership education. The ability of students to demonstrate leadership outcome mastery in areas of communication, self-awareness, interpersonal interactions, and civic…

Coping with Constraints: Reflecting on Responsibilities.

ERIC Educational Resources Information Center

Johnson, Nancy J.

2001-01-01

Discusses common threads found in the four articles written by teachers in this themed journal issue on coping with mandated curriculum. Discusses the teachers' commitment to professional responsibility expressed as their responsibility to: learn about learning, demonstrate how learning works, make the best teaching decisions possible, remain…

Verbal Rehearsal and Visual Imagery: Mnemonic Aids for Learning-Disabled Children.

ERIC Educational Resources Information Center

Rose, Michael C.; And Others

1983-01-01

Studies involving 30 learning-disabled elementary students support the contention that reading comprehension difficulties among learning-disabled children are partly due to inefficient memorization strategies, and demonstrate the efficacy of practical, cost-effective mnemonic training procedures which significantly increase reading comprehension…

Learning through Collaboration: Student Perspectives

ERIC Educational Resources Information Center

Osman, Gihan; Duffy, Thomas M.; Chang, Ju-yu; Lee, Jieun

2011-01-01

This research examines the effectiveness of collaborative learning pedagogies from the perspective of students. There is a rich history of research on collaborative learning demonstrating the effectiveness and this has led to indexing educational quality by student engagement. However, the findings from this study question the efficacy of…

Generalization of Perceptual Learning of Vocoded Speech

ERIC Educational Resources Information Center

Hervais-Adelman, Alexis G.; Davis, Matthew H.; Johnsrude, Ingrid S.; Taylor, Karen J.; Carlyon, Robert P.

2011-01-01

Recent work demonstrates that learning to understand noise-vocoded (NV) speech alters sublexical perceptual processes but is enhanced by the simultaneous provision of higher-level, phonological, but not lexical content (Hervais-Adelman, Davis, Johnsrude, & Carlyon, 2008), consistent with top-down learning (Davis, Johnsrude, Hervais-Adelman,…

Create Learning Systems, Not Silos

ERIC Educational Resources Information Center

Hirsh, Stephanie; Psencik, Kay; Brown, Frederick

2018-01-01

In a learning system, central office personnel assume collective responsibility for schools and go about their work very differently. They are responsible not only for departments and programs, but also for student learning. They demonstrate that responsibility by engaging in data informed conversations about student achievement. Central office…

Adaptive Computerized Instruction.

ERIC Educational Resources Information Center

Ray, Roger D.; And Others

1995-01-01

Describes an artificially intelligent multimedia computerized instruction system capable of developing a conceptual image of what a student is learning while the student is learning it. It focuses on principles of learning and adaptive behavioral control systems theory upon which the system is designed and demonstrates multiple user modes.…

Civil Society, Adult Learning and Action in India.

ERIC Educational Resources Information Center

Tandon, Rajesh

2000-01-01

Five case studies of individual and collective learning projects in India demonstrate that (1) the impetus for civic action arises from local conditions; (2) transformative action requires sustained adult learning; and (3) civil society is a complex concept reflecting diverse priorities and perspectives. (SK)

Word learning in deaf children with cochlear implants: effects of early auditory experience.

PubMed

Houston, Derek M; Stewart, Jessica; Moberly, Aaron; Hollich, George; Miyamoto, Richard T

2012-05-01

Word-learning skills were tested in normal-hearing 12- to 40-month-olds and in deaf 22- to 40-month-olds 12 to 18 months after cochlear implantation. Using the Intermodal Preferential Looking Paradigm (IPLP), children were tested for their ability to learn two novel-word/novel-object pairings. Normal-hearing children demonstrated learning on this task at approximately 18 months of age and older. For deaf children, performance on this task was significantly correlated with early auditory experience: Children whose cochlear implants were switched on by 14 months of age or who had relatively more hearing before implantation demonstrated learning in this task, but later implanted profoundly deaf children did not. Performance on this task also correlated with later measures of vocabulary size. Taken together, these findings suggest that early auditory experience facilitates word learning and that the IPLP may be useful for identifying children who may be at high risk for poor vocabulary development. © 2012 Blackwell Publishing Ltd.

The curse of planning: dissecting multiple reinforcement-learning systems by taxing the central executive.

PubMed

Otto, A Ross; Gershman, Samuel J; Markman, Arthur B; Daw, Nathaniel D

2013-05-01

A number of accounts of human and animal behavior posit the operation of parallel and competing valuation systems in the control of choice behavior. In these accounts, a flexible but computationally expensive model-based reinforcement-learning system has been contrasted with a less flexible but more efficient model-free reinforcement-learning system. The factors governing which system controls behavior-and under what circumstances-are still unclear. Following the hypothesis that model-based reinforcement learning requires cognitive resources, we demonstrated that having human decision makers perform a demanding secondary task engenders increased reliance on a model-free reinforcement-learning strategy. Further, we showed that, across trials, people negotiate the trade-off between the two systems dynamically as a function of concurrent executive-function demands, and people's choice latencies reflect the computational expenses of the strategy they employ. These results demonstrate that competition between multiple learning systems can be controlled on a trial-by-trial basis by modulating the availability of cognitive resources.

The Curse of Planning: Dissecting multiple reinforcement learning systems by taxing the central executive

PubMed Central

Otto, A. Ross; Gershman, Samuel J.; Markman, Arthur B.; Daw, Nathaniel D.

2013-01-01

A number of accounts of human and animal behavior posit the operation of parallel and competing valuation systems in the control of choice behavior. Along these lines, a flexible but computationally expensive model-based reinforcement learning system has been contrasted with a less flexible but more efficient model-free reinforcement learning system. The factors governing which system controls behavior—and under what circumstances—are still unclear. Based on the hypothesis that model-based reinforcement learning requires cognitive resources, we demonstrate that having human decision-makers perform a demanding secondary task engenders increased reliance on a model-free reinforcement learning strategy. Further, we show that across trials, people negotiate this tradeoff dynamically as a function of concurrent executive function demands and their choice latencies reflect the computational expenses of the strategy employed. These results demonstrate that competition between multiple learning systems can be controlled on a trial-by-trial basis by modulating the availability of cognitive resources. PMID:23558545

Word learning in deaf children with cochlear implants: effects of early auditory experience

PubMed Central

Houston, Derek M.; Stewart, Jessica; Moberly, Aaron; Hollich, George; Miyamoto, Richard T.

2013-01-01

Word-learning skills were tested in normal-hearing 12- to 40-month-olds and in deaf 22- to 40-month-olds 12 to 18 months after cochlear implantation. Using the Intermodal Preferential Looking Paradigm (IPLP), children were tested for their ability to learn two novel-word/novel-object pairings. Normal-hearing children demonstrated learning on this task at approximately 18 months of age and older. For deaf children, performance on this task was significantly correlated with early auditory experience: Children whose cochlear implants were switched on by 14 months of age or who had relatively more hearing before implantation demonstrated learning in this task, but later implanted profoundly deaf children did not. Performance on this task also correlated with later measures of vocabulary size. Taken together, these findings suggest that early auditory experience facilitates word learning and that the IPLP may be useful for identifying children who may be at high risk for poor vocabulary development. PMID:22490184

Learned helplessness or learned inactivity after inescapable stress? Interpretation depends on coping styles.

PubMed

Zhukov, D A; Vinogradova, K P

2002-01-01

Researches on uncontrollable events in the post-soviet states are overviewed. In our research, susceptibility to learned helplessness is studied in rats with active (KHA strain) versus passive (KLA strain) coping styles. Inescapable footshocks, but not escapable footshocks, applied to KHA rats induced escape failures, diminished locomotion and coping, reduced measures of anxiety, and resulted in dexamethasone nonsuppression of the brain-hypothalamus-pituitary-adrenal axis--all characteristic of learned helplessness. In contrast, KLA rats demonstrated the same responses upon exposure to both escapable and inescapable stresses. While learned helplessness occurred in KHA rats, it appears that KLA rats exposed to inescapable stress demonstrated learned inactivity based upon the nondifference between effects of escapable and inescapable shocks. Relationships between coping styles and social ranks are discussed. Our and other's results with genetically selected strains suggest active coping in dominant and subordinate subjects, and passive coping in subdominant animals confirm the importance of coping style and its relation to health under stress.

Utilization of blended learning to teach preclinical endodontics.

PubMed

Maresca, Cristina; Barrero, Carlos; Duggan, Dereck; Platin, Enrique; Rivera, Eric; Hannum, Wallace; Petrola, Frank

2014-08-01

Blended learning (BL) is the integration of classroom learning with an online environment. The purpose of this study was to determine whether dental students who experienced BL in a preclinical endodontic course demonstrated better manual skills, conceptual knowledge, and learning experience compared to those experiencing traditional learning. All eighty-one students (100 percent) in a preclinical endodontics course agreed to participate and were assigned to either the traditional or BL group. A root canal procedure was used to determine the level of manual skills gained by each group. Pre- and post-intervention quizzes were given to all students to evaluate conceptual knowledge gained, and the students' perspectives on the methods were evaluated with a survey. The BL group scored better than the traditional group on the manual skills exercise at a statistically significant level (p=0.0067). There were no differences in the post-intervention quiz scores between the two groups, and the students' opinions were positive regarding BL. With BL, the students were able to learn and demonstrate dental skills at a high level.

From modulated Hebbian plasticity to simple behavior learning through noise and weight saturation.

PubMed

Soltoggio, Andrea; Stanley, Kenneth O

2012-10-01

Synaptic plasticity is a major mechanism for adaptation, learning, and memory. Yet current models struggle to link local synaptic changes to the acquisition of behaviors. The aim of this paper is to demonstrate a computational relationship between local Hebbian plasticity and behavior learning by exploiting two traditionally unwanted features: neural noise and synaptic weight saturation. A modulation signal is employed to arbitrate the sign of plasticity: when the modulation is positive, the synaptic weights saturate to express exploitative behavior; when it is negative, the weights converge to average values, and neural noise reconfigures the network's functionality. This process is demonstrated through simulating neural dynamics in the autonomous emergence of fearful and aggressive navigating behaviors and in the solution to reward-based problems. The neural model learns, memorizes, and modifies different behaviors that lead to positive modulation in a variety of settings. The algorithm establishes a simple relationship between local plasticity and behavior learning by demonstrating the utility of noise and weight saturation. Moreover, it provides a new tool to simulate adaptive behavior, and contributes to bridging the gap between synaptic changes and behavior in neural computation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Learning compliant manipulation through kinesthetic and tactile human-robot interaction.

PubMed

Kronander, Klas; Billard, Aude

2014-01-01

Robot Learning from Demonstration (RLfD) has been identified as a key element for making robots useful in daily lives. A wide range of techniques has been proposed for deriving a task model from a set of demonstrations of the task. Most previous works use learning to model the kinematics of the task, and for autonomous execution the robot then relies on a stiff position controller. While many tasks can and have been learned this way, there are tasks in which controlling the position alone is insufficient to achieve the goals of the task. These are typically tasks that involve contact or require a specific response to physical perturbations. The question of how to adjust the compliance to suit the need of the task has not yet been fully treated in Robot Learning from Demonstration. In this paper, we address this issue and present interfaces that allow a human teacher to indicate compliance variations by physically interacting with the robot during task execution. We validate our approach in two different experiments on the 7 DoF Barrett WAM and KUKA LWR robot manipulators. Furthermore, we conduct a user study to evaluate the usability of our approach from a non-roboticists perspective.

Addressing uncertainty in atomistic machine learning.

PubMed

Peterson, Andrew A; Christensen, Rune; Khorshidi, Alireza

2017-05-10

Machine-learning regression has been demonstrated to precisely emulate the potential energy and forces that are output from more expensive electronic-structure calculations. However, to predict new regions of the potential energy surface, an assessment must be made of the credibility of the predictions. In this perspective, we address the types of errors that might arise in atomistic machine learning, the unique aspects of atomistic simulations that make machine-learning challenging, and highlight how uncertainty analysis can be used to assess the validity of machine-learning predictions. We suggest this will allow researchers to more fully use machine learning for the routine acceleration of large, high-accuracy, or extended-time simulations. In our demonstrations, we use a bootstrap ensemble of neural network-based calculators, and show that the width of the ensemble can provide an estimate of the uncertainty when the width is comparable to that in the training data. Intriguingly, we also show that the uncertainty can be localized to specific atoms in the simulation, which may offer hints for the generation of training data to strategically improve the machine-learned representation.

Learning to fear a second-order stimulus following vicarious learning.

PubMed

Reynolds, Gemma; Field, Andy P; Askew, Chris

2017-04-01

Vicarious fear learning refers to the acquisition of fear via observation of the fearful responses of others. The present study aims to extend current knowledge by exploring whether second-order vicarious fear learning can be demonstrated in children. That is, whether vicariously learnt fear responses for one stimulus can be elicited in a second stimulus associated with that initial stimulus. Results demonstrated that children's (5-11 years) fear responses for marsupials and caterpillars increased when they were seen with fearful faces compared to no faces. Additionally, the results indicated a second-order effect in which fear-related learning occurred for other animals seen together with the fear-paired animal, even though the animals were never observed with fearful faces themselves. Overall, the findings indicate that for children in this age group vicariously learnt fear-related responses for one stimulus can subsequently be observed for a second stimulus without it being experienced in a fear-related vicarious learning event. These findings may help to explain why some individuals do not recall involvement of a traumatic learning episode in the development of their fear of a specific stimulus.

Punishment Learning in U.S. Veterans With Posttraumatic Stress Disorder.

PubMed

Sawyer, Alice T; Liverant, Gabrielle I; Jun, Janie J; Lee, Daniel J; Cohen, Andrew L; Dutra, Sunny J; Pizzagalli, Diego A; Sloan, Denise M

2016-08-01

Learning processes have been implicated in the development and course of posttraumatic stress disorder (PTSD); however, little is currently known about punishment-based learning in PTSD. The current study investigated impairments in punishment-based learning in U.S. veterans. We expected that veterans with PTSD would demonstrate greater punishment-based learning compared to a non-PTSD control group. We compared a PTSD group with and without co-occurring depression (n = 27) to a control group (with and without trauma exposure) without PTSD or depression (n = 29). Participants completed a computerized probabilistic punishment-based learning task. Compared to the non-PTSD control group, veterans with PTSD showed significantly greater punishment-based learning. Specifically, there was a significant Block × Group interaction, F(1, 54) = 4.12, p = .047, η(2) = .07. Veterans with PTSD demonstrated greater change in response bias for responding toward a less frequently punished stimulus across blocks. The observed hypersensitivity to punishment in individuals with PTSD may contribute to avoidant responses that are not specific to trauma cues. Copyright © 2016 International Society for Traumatic Stress Studies No claim to original US government works.

Hippocampal participation in navigational map learning in young homing pigeons is dependent on training experience.

PubMed

Ioalè, P; Gagliardo, A; Bingman, V P

2000-02-01

The homing pigeon navigational map is perhaps one of the most striking examples of a naturally occurring spatial representation of the environment used to guide navigation. In a previous study, it was found that hippocampal lesions thoroughly disrupt the ability of young homing pigeons held in an outdoor aviary to learn a navigational map. However, since that study an accumulation of anecdotal data has hinted that hippocampal-lesioned young pigeons allowed to fly during their first summer could learn a navigational map. In the present study, young control and hippocampal-lesioned homing pigeons were either held in an outdoor aviary or allowed to fly during the time of navigational map learning. At the end of their first summer, the birds were experimentally released to test for navigational map learning. Independent of training experience, control pigeons oriented homeward during the experimental releases demonstrating that they learned a navigational map. Surprisingly, while the aviary-held hippocampal-lesioned pigeons failed to learn a navigational map as reported previously, hippocampal-lesioned birds allowed flight experience learned a navigational map indistinguishable from the two control groups. A subsequent experiment revealed that the navigational map learned by the three groups was based on atmospheric odours. The results demonstrate that hippocampal participation in navigational map learning depends on the type of experience a young bird pigeon has, and presumably, the type of navigational map learned.

Learning by stimulation avoidance: A principle to control spiking neural networks dynamics

PubMed Central

Sinapayen, Lana; Ikegami, Takashi

2017-01-01

Learning based on networks of real neurons, and learning based on biologically inspired models of neural networks, have yet to find general learning rules leading to widespread applications. In this paper, we argue for the existence of a principle allowing to steer the dynamics of a biologically inspired neural network. Using carefully timed external stimulation, the network can be driven towards a desired dynamical state. We term this principle “Learning by Stimulation Avoidance” (LSA). We demonstrate through simulation that the minimal sufficient conditions leading to LSA in artificial networks are also sufficient to reproduce learning results similar to those obtained in biological neurons by Shahaf and Marom, and in addition explains synaptic pruning. We examined the underlying mechanism by simulating a small network of 3 neurons, then scaled it up to a hundred neurons. We show that LSA has a higher explanatory power than existing hypotheses about the response of biological neural networks to external simulation, and can be used as a learning rule for an embodied application: learning of wall avoidance by a simulated robot. In other works, reinforcement learning with spiking networks can be obtained through global reward signals akin simulating the dopamine system; we believe that this is the first project demonstrating sensory-motor learning with random spiking networks through Hebbian learning relying on environmental conditions without a separate reward system. PMID:28158309

Learning by stimulation avoidance: A principle to control spiking neural networks dynamics.

PubMed

Sinapayen, Lana; Masumori, Atsushi; Ikegami, Takashi

2017-01-01

Learning based on networks of real neurons, and learning based on biologically inspired models of neural networks, have yet to find general learning rules leading to widespread applications. In this paper, we argue for the existence of a principle allowing to steer the dynamics of a biologically inspired neural network. Using carefully timed external stimulation, the network can be driven towards a desired dynamical state. We term this principle "Learning by Stimulation Avoidance" (LSA). We demonstrate through simulation that the minimal sufficient conditions leading to LSA in artificial networks are also sufficient to reproduce learning results similar to those obtained in biological neurons by Shahaf and Marom, and in addition explains synaptic pruning. We examined the underlying mechanism by simulating a small network of 3 neurons, then scaled it up to a hundred neurons. We show that LSA has a higher explanatory power than existing hypotheses about the response of biological neural networks to external simulation, and can be used as a learning rule for an embodied application: learning of wall avoidance by a simulated robot. In other works, reinforcement learning with spiking networks can be obtained through global reward signals akin simulating the dopamine system; we believe that this is the first project demonstrating sensory-motor learning with random spiking networks through Hebbian learning relying on environmental conditions without a separate reward system.

Learning control system design based on 2-D theory - An application to parallel link manipulator

NASA Technical Reports Server (NTRS)

Geng, Z.; Carroll, R. L.; Lee, J. D.; Haynes, L. H.

1990-01-01

An approach to iterative learning control system design based on two-dimensional system theory is presented. A two-dimensional model for the iterative learning control system which reveals the connections between learning control systems and two-dimensional system theory is established. A learning control algorithm is proposed, and the convergence of learning using this algorithm is guaranteed by two-dimensional stability. The learning algorithm is applied successfully to the trajectory tracking control problem for a parallel link robot manipulator. The excellent performance of this learning algorithm is demonstrated by the computer simulation results.

How we learn to make decisions: rapid propagation of reinforcement learning prediction errors in humans.

PubMed

Krigolson, Olav E; Hassall, Cameron D; Handy, Todd C

2014-03-01

Our ability to make decisions is predicated upon our knowledge of the outcomes of the actions available to us. Reinforcement learning theory posits that actions followed by a reward or punishment acquire value through the computation of prediction errors-discrepancies between the predicted and the actual reward. A multitude of neuroimaging studies have demonstrated that rewards and punishments evoke neural responses that appear to reflect reinforcement learning prediction errors [e.g., Krigolson, O. E., Pierce, L. J., Holroyd, C. B., & Tanaka, J. W. Learning to become an expert: Reinforcement learning and the acquisition of perceptual expertise. Journal of Cognitive Neuroscience, 21, 1833-1840, 2009; Bayer, H. M., & Glimcher, P. W. Midbrain dopamine neurons encode a quantitative reward prediction error signal. Neuron, 47, 129-141, 2005; O'Doherty, J. P. Reward representations and reward-related learning in the human brain: Insights from neuroimaging. Current Opinion in Neurobiology, 14, 769-776, 2004; Holroyd, C. B., & Coles, M. G. H. The neural basis of human error processing: Reinforcement learning, dopamine, and the error-related negativity. Psychological Review, 109, 679-709, 2002]. Here, we used the brain ERP technique to demonstrate that not only do rewards elicit a neural response akin to a prediction error but also that this signal rapidly diminished and propagated to the time of choice presentation with learning. Specifically, in a simple, learnable gambling task, we show that novel rewards elicited a feedback error-related negativity that rapidly decreased in amplitude with learning. Furthermore, we demonstrate the existence of a reward positivity at choice presentation, a previously unreported ERP component that has a similar timing and topography as the feedback error-related negativity that increased in amplitude with learning. The pattern of results we observed mirrored the output of a computational model that we implemented to compute reward prediction errors and the changes in amplitude of these prediction errors at the time of choice presentation and reward delivery. Our results provide further support that the computations that underlie human learning and decision-making follow reinforcement learning principles.

Self-learning Monte Carlo with deep neural networks

NASA Astrophysics Data System (ADS)

Shen, Huitao; Liu, Junwei; Fu, Liang

2018-05-01

The self-learning Monte Carlo (SLMC) method is a general algorithm to speedup MC simulations. Its efficiency has been demonstrated in various systems by introducing an effective model to propose global moves in the configuration space. In this paper, we show that deep neural networks can be naturally incorporated into SLMC, and without any prior knowledge can learn the original model accurately and efficiently. Demonstrated in quantum impurity models, we reduce the complexity for a local update from O (β2) in Hirsch-Fye algorithm to O (β lnβ ) , which is a significant speedup especially for systems at low temperatures.

Word Learning in Deaf Children with Cochlear Implants: Effects of Early Auditory Experience

ERIC Educational Resources Information Center

Houston, Derek M.; Stewart, Jessica; Moberly, Aaron; Hollich, George; Miyamoto, Richard T.

2012-01-01

Word-learning skills were tested in normal-hearing 12- to 40-month-olds and in deaf 22- to 40-month-olds 12 to 18 months after cochlear implantation. Using the Intermodal Preferential Looking Paradigm (IPLP), children were tested for their ability to learn two novel-word/novel-object pairings. Normal-hearing children demonstrated learning on this…

A Role of Protein Degradation in Memory Consolidation after Initial Learning and Extinction Learning in the Honeybee ("Apis mellifera")

ERIC Educational Resources Information Center

Felsenberg, Johannes; Dombrowski, Vincent; Eisenhardt, Dorothea

2012-01-01

Protein degradation is known to affect memory formation after extinction learning. We demonstrate here that an inhibitor of protein degradation, MG132, interferes with memory formation after extinction learning in a classical appetitive conditioning paradigm. In addition, we find an enhancement of memory formation when the same inhibitor is…

"Of Course I'm Communicating; I Lecture Every Day": Enhancing Teaching and Learning in Introductory Statistics. Scholarship of Teaching and Learning

ERIC Educational Resources Information Center

Wulff, Shaun S.; Wulff, Donald H.

2004-01-01

This article focuses on one instructor's evolution from formal lecturing to interactive teaching and learning in a statistics course. Student perception data are used to demonstrate the instructor's use of communication to align the content, students, and instructor throughout the course. Results indicate that the students learned, that…

The Inseparability of Cognition and Emotion in Second Language Learning

ERIC Educational Resources Information Center

Swain, Merrill

2013-01-01

The scholarly literature about the process of second language (L2) learning has focused to a considerable extent on cognitive processes. Left aside are questions about how emotions fit into an understanding of L2 learning. One goal of this plenary is to demonstrate that we have limited our understanding of L2 learning by failing to take into…

Orthographic Learning and the Role of Text-to-Speech Software in Dutch Disabled Readers

ERIC Educational Resources Information Center

Staels, Eva; Van den Broeck, Wim

2015-01-01

In this study, we examined whether orthographic learning can be demonstrated in disabled readers learning to read in a transparent orthography (Dutch). In addition, we tested the effect of the use of text-to-speech software, a new form of direct instruction, on orthographic learning. Both research goals were investigated by replicating Share's…

Parents Supporting Learning: A Non-Intensive Intervention Supporting Literacy and Numeracy in the Home Learning Environment

ERIC Educational Resources Information Center

Niklas, Frank; Cohrssen, Caroline; Tayler, Collette

2016-01-01

In Australia, emphasis in early childhood education policy is placed on the importance of the role of the family as a child's first educator, and finding effective ways to raise the effectiveness of parents in supporting children's learning, development and well-being. International studies demonstrate that the home learning environment (HLE)…

Effects of Active Learning Classrooms on Student Learning: A Two-Year Empirical Investigation on Student Perceptions and Academic Performance

ERIC Educational Resources Information Center

Chiu, Pit Ho Patrio; Cheng, Shuk Han

2017-01-01

Recent studies on active learning classrooms (ACLs) have demonstrated their positive influence on student learning. However, most of the research evidence is derived from a few subject-specific courses or limited student enrolment. Empirical studies on this topic involving large student populations are rare. The present work involved a large-scale…

Connectedness through a Strong Form of TBLT, Classroom Implementation of the CEFR, Cyclical Learning, and Learning-Oriented Assessment

ERIC Educational Resources Information Center

O'Dwyer, Fergus; Imig, Alexander; Nagai, Noriko

2014-01-01

This paper, fundamentally a procedural paper, outlines pedagogical practices which others may want to adapt for their own purposes. We demonstrate how a strong form of task-based language learning and teaching (TBLT), classroom implementation of the CEFR, cyclical learning, and assessment fulfilling roles, such as informing the next learning…

Infants Encode Phonetic Detail during Cross-Situational Word Learning

PubMed Central

Escudero, Paola; Mulak, Karen E.; Vlach, Haley A.

2016-01-01

Infants often hear new words in the context of more than one candidate referent. In cross-situational word learning (XSWL), word-object mappings are determined by tracking co-occurrences of words and candidate referents across multiple learning events. Research demonstrates that infants can learn words in XSWL paradigms, suggesting that it is a viable model of real-world word learning. However, these studies have all presented infants with words that have no or minimal phonological overlap (e.g., BLICKET and GAX). Words often contain some degree of phonological overlap, and it is unknown whether infants can simultaneously encode fine phonological detail while learning words via XSWL. We tested 12-, 15-, 17-, and 20-month-olds’ XSWL of eight words that, when paired, formed non-minimal pairs (MPs; e.g., BON–DEET) or MPs (e.g., BON–TON, DEET–DIT). The results demonstrated that infants are able to learn word-object mappings and encode them with sufficient phonetic detail as to identify words in both non-minimal and MP contexts. Thus, this work suggests that infants are able to simultaneously discriminate phonetic differences between words and map words to referents in an implicit learning paradigm such as XSWL. PMID:27708605

Habituation based synaptic plasticity and organismic learning in a quantum perovskite.

PubMed

Zuo, Fan; Panda, Priyadarshini; Kotiuga, Michele; Li, Jiarui; Kang, Mingu; Mazzoli, Claudio; Zhou, Hua; Barbour, Andi; Wilkins, Stuart; Narayanan, Badri; Cherukara, Mathew; Zhang, Zhen; Sankaranarayanan, Subramanian K R S; Comin, Riccardo; Rabe, Karin M; Roy, Kaushik; Ramanathan, Shriram

2017-08-14

A central characteristic of living beings is the ability to learn from and respond to their environment leading to habit formation and decision making. This behavior, known as habituation, is universal among all forms of life with a central nervous system, and is also observed in single-cell organisms that do not possess a brain. Here, we report the discovery of habituation-based plasticity utilizing a perovskite quantum system by dynamical modulation of electron localization. Microscopic mechanisms and pathways that enable this organismic collective charge-lattice interaction are elucidated by first-principles theory, synchrotron investigations, ab initio molecular dynamics simulations, and in situ environmental breathing studies. We implement a learning algorithm inspired by the conductance relaxation behavior of perovskites that naturally incorporates habituation, and demonstrate learning to forget: a key feature of animal and human brains. Incorporating this elementary skill in learning boosts the capability of neural computing in a sequential, dynamic environment.Habituation is a learning mechanism that enables control over forgetting and learning. Zuo, Panda et al., demonstrate adaptive synaptic plasticity in SmNiO 3 perovskites to address catastrophic forgetting in a dynamic learning environment via hydrogen-induced electron localization.

Contextual remapping in visual search after predictable target-location changes.

PubMed

Conci, Markus; Sun, Luning; Müller, Hermann J

2011-07-01

Invariant spatial context can facilitate visual search. For instance, detection of a target is faster if it is presented within a repeatedly encountered, as compared to a novel, layout of nontargets, demonstrating a role of contextual learning for attentional guidance ('contextual cueing'). Here, we investigated how context-based learning adapts to target location (and identity) changes. Three experiments were performed in which, in an initial learning phase, observers learned to associate a given context with a given target location. A subsequent test phase then introduced identity and/or location changes to the target. The results showed that contextual cueing could not compensate for target changes that were not 'predictable' (i.e. learnable). However, for predictable changes, contextual cueing remained effective even immediately after the change. These findings demonstrate that contextual cueing is adaptive to predictable target location changes. Under these conditions, learned contextual associations can be effectively 'remapped' to accommodate new task requirements.

Correlation Filter Learning Toward Peak Strength for Visual Tracking.

PubMed

Sui, Yao; Wang, Guanghui; Zhang, Li

2018-04-01

This paper presents a novel visual tracking approach to correlation filter learning toward peak strength of correlation response. Previous methods leverage all features of the target and the immediate background to learn a correlation filter. Some features, however, may be distractive to tracking, like those from occlusion and local deformation, resulting in unstable tracking performance. This paper aims at solving this issue and proposes a novel algorithm to learn the correlation filter. The proposed approach, by imposing an elastic net constraint on the filter, can adaptively eliminate those distractive features in the correlation filtering. A new peak strength metric is proposed to measure the discriminative capability of the learned correlation filter. It is demonstrated that the proposed approach effectively strengthens the peak of the correlation response, leading to more discriminative performance than previous methods. Extensive experiments on a challenging visual tracking benchmark demonstrate that the proposed tracker outperforms most state-of-the-art methods.

Low Data Drug Discovery with One-Shot Learning.

PubMed

Altae-Tran, Han; Ramsundar, Bharath; Pappu, Aneesh S; Pande, Vijay

2017-04-26

Recent advances in machine learning have made significant contributions to drug discovery. Deep neural networks in particular have been demonstrated to provide significant boosts in predictive power when inferring the properties and activities of small-molecule compounds (Ma, J. et al. J. Chem. Inf. 2015, 55, 263-274). However, the applicability of these techniques has been limited by the requirement for large amounts of training data. In this work, we demonstrate how one-shot learning can be used to significantly lower the amounts of data required to make meaningful predictions in drug discovery applications. We introduce a new architecture, the iterative refinement long short-term memory, that, when combined with graph convolutional neural networks, significantly improves learning of meaningful distance metrics over small-molecules. We open source all models introduced in this work as part of DeepChem, an open-source framework for deep-learning in drug discovery (Ramsundar, B. deepchem.io. https://github.com/deepchem/deepchem, 2016).

Research on teacher education programs: logic model approach.

PubMed

Newton, Xiaoxia A; Poon, Rebecca C; Nunes, Nicole L; Stone, Elisa M

2013-02-01

Teacher education programs in the United States face increasing pressure to demonstrate their effectiveness through pupils' learning gains in classrooms where program graduates teach. The link between teacher candidates' learning in teacher education programs and pupils' learning in K-12 classrooms implicit in the policy discourse suggests a one-to-one correspondence. However, the logical steps leading from what teacher candidates have learned in their programs to what they are doing in classrooms that may contribute to their pupils' learning are anything but straightforward. In this paper, we argue that the logic model approach from scholarship on evaluation can enhance research on teacher education by making explicit the logical links between program processes and intended outcomes. We demonstrate the usefulness of the logic model approach through our own work on designing a longitudinal study that focuses on examining the process and impact of an undergraduate mathematics and science teacher education program. Copyright © 2012 Elsevier Ltd. All rights reserved.

High fidelity simulation effectiveness in nursing students' transfer of learning.

PubMed

Kirkman, Tera R

2013-07-13

Members of nursing faculty are utilizing interactive teaching tools to improve nursing student's clinical judgment; one method that has been found to be potentially effective is high fidelity simulation (HFS). The purpose of this time series design study was to determine whether undergraduate nursing students were able to transfer knowledge and skills learned from classroom lecture and a HFS clinical to the traditional clinical setting. Students (n=42) were observed and rated on their ability to perform a respiratory assessment. The observations and ratings took place at the bedside, prior to a respiratory lecture, following the respiratory lecture, and following simulation clinical. The findings indicated that there was a significant difference (p=0.000) in transfer of learning demonstrated over time. Transfer of learning was demonstrated and the use of HFS was found to be an effective learning and teaching method. Implications of results are discussed.

Differences in Learning Styles of Dominican and Puerto Rican Students: We Are Latinos from the Caribbean; Our First Language Is Spanish, However; Our Learning Preferences Are Different

ERIC Educational Resources Information Center

Maldonado-Torres, Sonia E.

2011-01-01

The purpose of this study was to examine the relationship between Dominican and Puerto Rican students' learning style. Findings of the study demonstrated differences between the learning preferences of Dominican and Puerto Rican students in the elements of Motivation (t = 2.846, p = 0.005), Several Ways of Learning (t = 2.351, p = 0.020), and…

Environmental enrichment improves learning and memory and long-term potentiation in young adult rats through a mechanism requiring mGluR5 signaling and sustained activation of p70s6k.

PubMed

Hullinger, Rikki; O'Riordan, Kenneth; Burger, Corinna

2015-11-01

Previous studies from our lab have demonstrated that mild cognitive impairments identified early in life are predictive of cognitive deficits that develop with age, suggesting that enhancements in cognition at an early age can provide a buffer against age-related cognitive decline. Environmental enrichment has been shown to improve learning and memory in the rodent, but the impact of enrichment on synaptic plasticity and the molecular mechanisms behind enrichment are not completely understood. To address these unresolved issues, we have housed 2-month old rats in environmentally enriched (EE), socially enriched (SE), or standard housing (SC) and conducted tests of learning and memory formation at various time intervals. Here we demonstrate that animals that have been exposed to one month of social or environmental enrichment demonstrate enhanced learning and memory relative to standard housed controls. However, we have found that after 4months EE animals perform better than both SE and SC groups and demonstrate an enhanced hippocampal LTP. Our results demonstrate that this LTP is dependent on mGluR5 signaling, activation of ERK and mTOR signaling cascades, and sustained phosphorylation of p70s6 kinase, thus providing a potential target mechanism for future studies of cognitive enhancement in the rodent. Copyright © 2015 Elsevier Inc. All rights reserved.

Incommensurate Practices: Sociomaterial Entanglements of Learning Technology Implementation

ERIC Educational Resources Information Center

Hannon, J.

2013-01-01

The framing of "implementation" of learning technologies in universities can have profound effects on approaches to teaching and learning that may be insufficiently acknowledged by practitioners. This paper investigates a case that demonstrated the formation of strong connections between technology and pedagogy, in which a learning…

Dancing the Curriculum

ERIC Educational Resources Information Center

Skoning, Stacey

2010-01-01

This article demonstrates how the use of creative movement and dance offers effective instructional strategies to meet the diverse learning needs of students in an inclusive classroom. Every day in one multi-age, fully inclusive classroom, students are meaningfully engaged in learning through movement--they move to learn science, social studies,…

Same-Different Categorization in Rats

ERIC Educational Resources Information Center

Wasserman, Edward A.; Castro, Leyre; Freeman, John H.

2012-01-01

Same-different categorization is a fundamental feat of human cognition. Although birds and nonhuman primates readily learn same-different discriminations and successfully transfer them to novel stimuli, no such demonstration exists for rats. Using a spatial discrimination learning task, we show that rats can both learn to discriminate arrays of…

Grading for Understanding--Standards-Based Grading

ERIC Educational Resources Information Center

Zimmerman, Todd

2017-01-01

Standards-based grading (SBG), sometimes called learning objectives-based assessment (LOBA), is an assessment model that relies on students demonstrating mastery of learning objectives (sometimes referred to as standards). The goal of this grading system is to focus students on mastering learning objectives rather than on accumulating points. I…

Language Acquisition and Language Learning: A Plea for Syncretism.

ERIC Educational Resources Information Center

Higgs, Theodore V.

1985-01-01

Discusses the apparent opposition between the concepts of language learning and language acquisition in the context of adult second-language study. Proposes that these two concepts are mutually supportive, not mutually exclusive. Demonstrates how the implications of learning vs. acquisition can be integrated into a communicative…

Child Development: An Active Learning Approach

ERIC Educational Resources Information Center

Levine, Laura E.; Munsch, Joyce

2010-01-01

Within each chapter of this innovative topical text, the authors engage students by demonstrating the wide range of real-world applications of psychological research connected to child development. In particular, the distinctive Active Learning features incorporated throughout the book foster a dynamic and personal learning process for students.…

Boosting Orthographic Learning during Independent Reading

ERIC Educational Resources Information Center

Nielsen, Anne-Mette Veber

2016-01-01

Research has shown that phonological decoding is critical for orthographic learning of new words during independent reading. Moreover, correlational studies have demonstrated that the strength of orthographic learning is related to the orthographic knowledge with which readers approach a text. The present training study was conducted to assess…

Designing Effective Classroom Assignments: Intellectual Work Worth Sharing

ERIC Educational Resources Information Center

Hutchings, Pat; Jankowski, Natasha A.; Schultz, Kathryn E.

2016-01-01

The National Institute for Learning Outcomes Assessment's (NILOA's) online library of faculty-created assignments that both produce and demonstrate learning makes pedagogical work visible and available for colleagues to learn from, build on, and reward. This online library allows faculty to collaborate in sharing, critiquing, and improving…

Lasting Consequences of the Summer Learning Gap

ERIC Educational Resources Information Center

Alexander, Karl L.; Entwisle, Doris R.; Olson, Linda Steffel

2007-01-01

Prior research has demonstrated that summer learning rooted in family and community influences widens the achievement gap across social lines, while schooling offsets those family and community influences. In this article, we examine the long-term educational consequences of summer learning differences by family socioeconomic level. Using data…

Student Engagement in the Scottish Quality Enhancement Framework

ERIC Educational Resources Information Center

Gvaramadze, Irakli

2011-01-01

The research addressed the interplay of student engagement and quality enhancement mechanisms in the Scottish higher education system. The paper demonstrates increasing focus on student learning, learning experience and high-quality learning in the current quality enhancement approaches. The student-university coproduction model is used to…

Attitudes Regarding Action Learning: Undergraduate vs. Graduate Business Students

ERIC Educational Resources Information Center

Rosenstein, Alvin; Ashley, Allan; Gupta, Rakesh; Ulin, Kristin

2008-01-01

Previous research in our Action Learning Program demonstrated that although undergraduates preferred the Action Learning mode to the traditional lecture and discussion mode of instruction, they missed the familiar structure of the more traditional pedagogy. Consequently increased structure was implemented in both an undergraduate and graduate…

Enhancing Academic Performance: Seven Perceptual Styles of Learning.

ERIC Educational Resources Information Center

Higbee, Jeanne L.; And Others

1991-01-01

Presents Galbraith and James's taxonomy of seven perceptual modalities (i.e., print, aural, interactive, visual, haptic, kinesthetic, and olfactory). Discusses ways educators can demonstrate perceptual modalities in the classroom and help students identify their personal style of learning. Explains how this knowledge can facilitate learning in a…

Associations of Middle School Student Science Achievement and Attitudes about Science with Student-Reported Frequency of Teacher Lecture Demonstrations and Student-Centered Learning

ERIC Educational Resources Information Center

Odom, Arthur Louis; Bell, Clare Valerie

2015-01-01

The purpose of this study was to examine the association of middle school student science achievement and attitudes about science with student-reported frequency of teacher lecture demonstrations and student-centered learning. The student sample was composed of 602 seventh- and eighth-grade students enrolled in middle school science. Multiple…

Infant Imitation from Television Using Novel Touch Screen Technology

ERIC Educational Resources Information Center

Zack, Elizabeth; Barr, Rachel; Gerhardstein, Peter; Dickerson, Kelly; Meltzoff, Andrew N.

2009-01-01

Infants learn less from a televised demonstration than from a live demonstration, the "video deficit effect." The present study employs a novel approach, using touch screen technology to examine 15-month olds' transfer of learning. Infants were randomly assigned either to within-dimension (2D/2D or 3D/3D) or cross-dimension (3D/2D or 2D/3D)…

D1 Receptor Activation in the Mushroom Bodies Rescues Sleep Loss Induced Learning Impairments in Drosophila

PubMed Central

Seugnet, Laurent; Suzuki, Yasuko; Vine, Lucy; Gottschalk, Laura; Shaw, Paul J

2008-01-01

Background Extended wakefulness disrupts acquisition of short term memories in mammals. However, the underlying molecular mechanisms triggered by extended waking and restored by sleep are unknown. Moreover, the neuronal circuits that depend on sleep for optimal learning remain unidentified. Results Learning was evaluated using Aversive Phototaxic Suppression (APS). In this task, flies learn to avoid light that is paired with an aversive stimulus (quinine /humidity). We demonstrate extensive homology in sleep deprivation induced learning impairment between flies and humans. Both 6 h and 12 h of sleep deprivation are sufficient to impair learning in Canton-S (Cs) flies. Moreover, learning is impaired at the end of the normal waking-day in direct correlation with time spent awake. Mechanistic studies indicate that this task requires intact mushroom bodies (MBs) and requires the Dopamine D1-like receptor (dDA1). Importantly, sleep deprivation induced learning impairments could be rescued by targeted gene expression of the dDA1 receptor to the MBs. Conclusion These data provide direct evidence that extended wakefulness disrupts learning in Drosophila. These results demonstrate that it is possible to prevent the effects of sleep deprivation by targeting a single neuronal structure and identify cellular and molecular targets adversely affected by extended waking in a genetically tractable model organism. PMID:18674913

Features of an effective operative dentistry learning environment: students' perceptions and relationship with performance.

PubMed

Suksudaj, N; Lekkas, D; Kaidonis, J; Townsend, G C; Winning, T A

2015-02-01

Students' perceptions of their learning environment influence the quality of outcomes they achieve. Learning dental operative techniques in a simulated clinic environment is characterised by reciprocal interactions between skills training, staff- and student-related factors. However, few studies have examined how students perceive their operative learning environments and whether there is a relationship between their perceptions and subsequent performance. Therefore, this study aimed to clarify which learning activities and interactions students perceived as supporting their operative skills learning and to examine relationships with their outcomes. Longitudinal data about examples of operative laboratory sessions that were perceived as effective or ineffective for learning were collected twice a semester, using written critical incidents and interviews. Emergent themes from these data were identified using thematic analysis. Associations between perceptions of learning effectiveness and performance were analysed using chi-square tests. Students indicated that an effective learning environment involved interactions with tutors and peers. This included tutors arranging group discussions to clarify processes and outcomes, providing demonstrations and constructive feedback. Feedback focused on mistakes, and not improvement, was reported as being ineffective for learning. However, there was no significant association between students' perceptions of the effectiveness of their learning experiences and subsequent performance. It was clear that learning in an operative technique setting involved various factors related not only to social interactions and observational aspects of learning but also to cognitive, motivational and affective processes. Consistent with studies that have demonstrated complex interactions between students, their learning environment and outcomes, other factors need investigation. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Age differences in spatial working memory contributions to visuomotor adaptation and transfer.

PubMed

Langan, Jeanne; Seidler, Rachael D

2011-11-20

Throughout our life span we encounter challenges that require us to adapt to the demands of our changing environment; this entails learning new skills. Two primary components of motor skill learning are motor acquisition, the initial process of learning the skill, and motor transfer, when learning a new skill is benefitted by the overlap with a previously learned one. Older adults typically exhibit declines in motor acquisition compared to young adults, but remarkably, do not demonstrate deficits in motor transfer [10]. Our recent work demonstrates that a failure to engage spatial working memory (SWM) is associated with skill learning deficits in older adults [16]. Here, we investigate the role that SWM plays in both motor learning and transfer in young and older adults. Both age groups exhibited performance savings, or positive transfer, at transfer of learning for some performance variables. Measures of spatial working memory performance and reaction time correlated with both motor learning and transfer for young adults. Young adults recruited overlapping brain regions in prefrontal, premotor, parietal and occipital cortex for performance of a SWM and a visuomotor adaptation task, most notably during motor learning, replicating our prior findings [12]. Neural overlap between the SWM task and visuomotor adaptation for the older adults was limited to parietal cortex, with minimal changes from motor learning to transfer. Combined, these results suggest that age differences in engagement of cognitive strategies have a differential impact on motor learning and transfer. Copyright © 2011 Elsevier B.V. All rights reserved.

Age differences in spatial working memory contributions to visuomotor adaptation and transfer

PubMed Central

Langan, Jeanne; Seidler, Rachael. D.

2011-01-01

Throughout our life span we encounter challenges that require us to adapt to the demands of our changing environment; this entails learning new skills. Two primary components of motor skill learning are motor acquisition, the initial process of learning the skill, and motor transfer, when learning a new skill is benefitted by the overlap with a previously learned one. Older adults typically exhibit declines in motor acquisition compared to young adults, but remarkably, do not demonstrate deficits in motor transfer (Seidler, 2007). Our recent work demonstrates that a failure to engage spatial working memory (SWM) is associated with skill learning deficits in older adults (Anguera et al., 2011). Here, we investigate the role that SWM plays in both motor learning and transfer in young and older adults. Both age groups exhibited performance savings, or positive transfer, at transfer of learning for some performance variables. Measures of spatial working memory performance and reaction time correlated with both motor learning and transfer for young adults. Young adults recruited overlapping brain regions in prefrontal, premotor, parietal and occipital cortex for performance of a SWM and a visuomotor adaptation task, most notably during motor learning, replicating our prior findings (Anguera et al., 2010). Neural overlap between the SWM task and visuomotor adaptation for the older adults was limited to parietal cortex, with minimal changes from motor learning to transfer. Combined, these results suggest that age differences in engagement of cognitive strategies have a differential impact on motor learning and transfer. PMID:21784106

New High Performance Water Vapor Membranes to Improve Fuel Cell Balance of Plant Efficiency and Lower Costs

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

Wagener, Earl; Topping, Chris; Morgan, Brad

Hydrogen fuel cells are currently one of the more promising long term alternative energy options and out of the range of fuel cell technologies under development, proton exchange membranes [PEMs] have the advantage of being able to deliver high power density at relatively low operating temperatures. This is essential for systems such as fuel cell vehicles (FCV) and many stationary applications that undergoing frequent on/off cycling. One of the biggest challenges for PEM systems is the need to maintain a high level of hydration in the cell to enable efficient conduction of protons from the anode to the cathode. Inmore » addition to significant power loss, low humidity conditions lead to increased stress on the membranes which can result in both physical and chemical degradation. Therefore, an effective fuel cell humidifier can be critical for the efficient operation and durability of the system under high load and low humidity conditions. The most common types of water vapor transport (WVT) devices are based on water permeable membrane based separators. Successful membranes must effectively permeate water vapor while restricting crossover of air, and be robust to the temperature and humidity fluctuations experienced in fuel cell systems. DOE sponsored independent evaluations indicate that balance of plant components, including humidification devices, make up more than half of the cost of current automotive fuel cell systems. Despite its relatively widespread us in other applications, the current industry standard perfluorosulfonic acid based Nafion® remains expensive compared with non-perfluorinated polymer membranes. During Phase II of this project, we demonstrated the improved performance of our semi-fluorinated perfluorocyclobutyl polymer based membranes compared with the current industry standard perfluorosulfonic acid based Nafion®, at ~ 50% lower cost. Building on this work, highlights of our Phase IIB developments, in close collaboration with leading global automotive component supplier Dana Holding Corporation include: • Development of a lower cost series of ionomers, with reduced synthetic steps and purification requirements and improved scale-ability, while maintaining performance advantages over Nafion® demonstrated during Phase II. • Demonstration of efficient, continuous production of down-selected WVT membrane configurations at commercial continuous roll coating facilities. We see no major issues producing Tetramer supported WVT membranes on a large commercial scale. • Following the production and testing of three prototype humidifier stacks, a full size humidifier unit was manufactured and successfully tested by an automotive customer for performance and durability. • Assuming the availability of a reasonably priced support, our cost projections for mid to large scale production of Tetramer WVT membranes are within the acceptable range of the leading automotive manufacturers and at a large scale, our calculations based on bulk sourcing of raw materials indicate we can achieve the project goal of $25/m2.« less

Adding Another Dimension to Learning: Application of Real World Globes to Undergraduate Geoscience Teaching

NASA Astrophysics Data System (ADS)

McLeod, C. L.; Kugler, A.

2016-12-01

The Geological Globe of the World (www.realworldglobes.com) promotes hands-on, in-class activities and allows students to engage with a physical 3-D model of Earth's characteristic, planet-forming geological features. The effectiveness of this concept in student learning has been demonstrated by two pilot studies presented as posters by Weeraratne et al. (2011) and Stoddard and Rogers (2013) at previous AGU meetings. The impact of the Geological Globe of the World on undergraduate teaching at Miami University, OH during Fall semester 2016 will be presented. It is anticipated that this teaching tool will have the biggest impact on the teaching of our 100-level lab course, GLG 155L, which engages 900 students per academic year. A Learning Assessment based on the learning objectives of GLG 115L has been written in order to demonstrate and evaluate the role of the Geological Globe in student learning. This Learning Assessment will be issued through www.salgsite.org (SALG: Student Assessment of Learning Gains) and will ask students to assess their own knowledge and understanding of key concepts before and after specific lab exercises which implement the globe. From research discussed in Bamford (2013), it has been demonstrated that "students learning with 3D teaching aids had better ordering of concepts and had enhanced skills in describing their learning, including writing more, saying more and being more likely to use models to demonstrate their (own) learning". It is anticipated that through use of the Geological Globe of the World students will be able to interpret Earth's geological features on a 3-D projection including topography, active volcanism, crustal movements and the location of seismic events. The incorporation of the Geological Globe of the World in undergraduate geoscience teaching in GLG 115L, and other departmental courses, aims to encourage students to make observations and collect data in order to interpret and evaluate relevant geological information. Bamford, A., (2013) The 3D in Education, White Paper. Stoddard, P. R and Rogers, D., (2013). Using Dry Erasable Globes in Earth and Space Science Classes. AGU Fall Meeting, #ED53G-0689 Weeraratne, D. S., Rogers, D. B., and Liedtke, J (2011). Teaching Seismic Methods Using Interactive 3-D Earth Globe, AGU Fall Meeting, #ED51B-0751

A Study of Ghanaian Early Childhood Teachers' Perceptions about Inclusive Education

ERIC Educational Resources Information Center

Ntuli, Esther; Traore, Moussa

2013-01-01

Inclusion is designed to bring special education services into the general classrooms. Research indicates that children with disabilities demonstrate better progress when learning with typically developing peers in general classrooms than they would in segregated learning environments. In inclusive classrooms, children with disabilities learn by…

Synchronous E-Learning: Reflections and Design Considerations

ERIC Educational Resources Information Center

Tabak, Filiz; Rampal, Rohit

2014-01-01

This paper is a personal reflection on the design, development, and delivery of online synchronous conferencing as a pedagogical tool complementing traditional, face-to-face content delivery and learning. The purpose of the paper is to demonstrate how instructors can combine collaborative and virtual learning principles in course design. In…

Early Education of the Language-Learning Handicapped Child.

ERIC Educational Resources Information Center

Easter Seal Treatment Center of Montgomery County, Rockville, MD.

The brochure descrbies a demonstration program on the early education of the language learning handicapped preschool child. Discussed are symptoms of the language learning problem (such as misunderstanding what is said), a remedial approach based on specific disability intervention, the Easter Seal Treatment Center, project objectives (such as the…

Service-Learning: Critical Traditions and Geographic Pedagogy

ERIC Educational Resources Information Center

Grabbatin, Brian; Fickey, Amanda

2012-01-01

The rise of service-learning in higher education has been critiqued as little more than community service that encourages students to "do good," but fails to generate original scholarship or social change. In this article, we argue that service-learning gives geographers the opportunity to challenge these critiques, by demonstrating the practical…

Learning to Work with Immigrant Families: An Experiment in Experiential Learning

ERIC Educational Resources Information Center

Ali, Mehrunnisa A.; Bishop, Susan; Martin, Beth

2017-01-01

This study examined what students in three professional programs--Nursing, Social Work, and Early Childhood Studies--could learn about working with immigrant families using narrative inquiry as a heuristic device. Data collected from the students in focus groups demonstrated their capacity for ethical caring by recognizing individual…

A Values Approach to Business Education in Hong Kong

ERIC Educational Resources Information Center

Radbourne, Jeniifer

2006-01-01

This paper investigates the learning behaviour, learning environment and learning outcomes of Hong Kong Chinese students enrolled on an Australian university's Bachelor of Business degree course taught by visiting Australian lecturers in Hong Kong. The Chinese students are task-focused and passive learners. They do not demonstrate creative…

Molecular and Cellular Biology Animations: Development and Impact on Student Learning

ERIC Educational Resources Information Center

McClean, Phillip; Johnson, Christina; Rogers, Roxanne; Daniels, Lisa; Reber, John; Slator, Brian M.; Terpstra, Jeff; White, Alan

2005-01-01

Educators often struggle when teaching cellular and molecular processes because typically they have only two-dimensional tools to teach something that plays out in four dimensions. Learning research has demonstrated that visualizing processes in three dimensions aids learning, and animations are effective visualization tools for novice learners…

Early Learning and Development: Cultural-Historical Concepts in Play

ERIC Educational Resources Information Center

Fleer, Marilyn

2010-01-01

"Early Learning and Development" provides a unique synthesis of cultural-historical theory from Vygotsky, Elkonin and Leontiev in the 20th century to the ground-breaking research of scholars such as Siraj-Blatchford, Kratsova and Hedegaard today. It demonstrates how development and learning are culturally embedded and institutionally defined, and…

Teaching Computer Science Courses in Distance Learning

ERIC Educational Resources Information Center

Huan, Xiaoli; Shehane, Ronald; Ali, Adel

2011-01-01

As the success of distance learning (DL) has driven universities to increase the courses offered online, certain challenges arise when teaching computer science (CS) courses to students who are not physically co-located and have individual learning schedules. Teaching CS courses involves high level demonstrations and interactivity between the…

Experimenting "Learn by Doing" and "Learn by Failing"

ERIC Educational Resources Information Center

Pozzi, Rossella; Noè, Carlo; Rossi, Tommaso

2015-01-01

According to the literature, in recent years, developing experiential learning has fulfilled the requirement of a deep understanding of lean philosophy by engineering students, demonstrating the advantages and disadvantages of some of the key principles of lean manufacturing. On the other hand, the literature evidences how some kinds of game-based…