Sample records for coli k-12 significantly

  1. Definition of Additional Flagellar Genes in ESCHERICHIA COLI K12


    Komeda, Yoshibumi; Kutsukake, Kazuhiro; Iino, Tetsuo


    Twenty-nine flagellar genes in Escherichia coli K12 have previously been assigned to three regions of the genome. Flagellar region I is located between pyrC and ptsG, region II between aroD and uvrC, and region III between uvrC and his. In this study, flagellar mutants in Escherichia coli K12 were obtained by selection for resistance to the flagellotropic phage, χ. They were analyzed in complementation tests using P1 phage-mediated transduction. In addition to the fla genes already described,...

  2. The comprehensive updated regulatory network of Escherichia coli K-12

    Directory of Open Access Journals (Sweden)

    Karp Peter D


    Full Text Available Abstract Background Escherichia coli is the model organism for which our knowledge of its regulatory network is the most extensive. Over the last few years, our project has been collecting and curating the literature concerning E. coli transcription initiation and operons, providing in both the RegulonDB and EcoCyc databases the largest electronically encoded network available. A paper published recently by Ma et al. (2004 showed several differences in the versions of the network present in these two databases. Discrepancies have been corrected, annotations from this and other groups (Shen-Orr et al., 2002 have been added, making the RegulonDB and EcoCyc databases the largest comprehensive and constantly curated regulatory network of E. coli K-12. Results Several groups have been using these curated data as part of their bioinformatics and systems biology projects, in combination with external data obtained from other sources, thus enlarging the dataset initially obtained from either RegulonDB or EcoCyc of the E. coli K12 regulatory network. We kindly obtained from the groups of Uri Alon and Hong-Wu Ma the interactions they have added to enrich their public versions of the E. coli regulatory network. These were used to search for original references and curate them with the same standards we use regularly, adding in several cases the original references (instead of reviews or missing references, as well as adding the corresponding experimental evidence codes. We also corrected all discrepancies in the two databases available as explained below. Conclusion One hundred and fifty new interactions have been added to our databases as a result of this specific curation effort, in addition to those added as a result of our continuous curation work. RegulonDB gene names are now based on those of EcoCyc to avoid confusion due to gene names and synonyms, and the public releases of RegulonDB and EcoCyc are henceforth synchronized to avoid confusion due to

  3. Development and maturation of Escherichia coli K-12 biofilms

    DEFF Research Database (Denmark)

    Reisner, A.; Haagensen, J.A.J.; Schembri, Mark


    The development and maturation of E. coli biofilms in flow-chambers was investigated. We found that the presence of transfer constitutive IncF plasmids induced biofilm development forming structures resembling those reported for Pseudomonas aeruginosa . The development occurred in a step-wise pro......The development and maturation of E. coli biofilms in flow-chambers was investigated. We found that the presence of transfer constitutive IncF plasmids induced biofilm development forming structures resembling those reported for Pseudomonas aeruginosa . The development occurred in a step....... We further provide evidence that flagella, type 1 fimbriae, curli and Ag43 are all dispensable for the observed biofilm maturation. In addition, our results indicate that cell-to-cell signalling mediated by autoinducer 2 (AI-2) is not required for differentiation of E. coli within a biofilm community....... We suggest on the basis of these results that E. coli K-12 biofilm development and maturation is dependent on cell-cell adhesion factors, which may act as inducers of self-assembly processes that result in differently structured biofilms depending on the adhesive properties on the cell surface....

  4. Escherichia coli K-12 pathogenicity in the pea aphid, Acyrthosiphon pisum, reveals reduced antibacterial defense in aphids. (United States)

    Altincicek, Boran; Ter Braak, Bas; Laughton, Alice M; Udekwu, Klas I; Gerardo, Nicole M


    To better understand the molecular basis underlying aphid immune tolerance to beneficial bacteria and immune defense to pathogenic bacteria, we characterized how the pea aphid Acyrthosiphon pisum responds to Escherichia coli K-12 infections. E. coli bacteria, usually cleared in the hemolymph of other insect species, were capable of growing exponentially and killing aphids within a few days. Red fluorescence protein expressing E. coli K-12 laboratory strain multiplied in the aphid hemolymph as well as in the digestive tract, resulting in death of infected aphids. Selected gene deletion mutants of the E. coli K-12 predicted to have reduced virulence during systemic infections showed no difference in either replication or killing rate when compared to the wild type E. coli strain. Of note, however, the XL1-Blue E. coli K-12 strain exhibited a significant lag phase before multiplying and killing aphids. This bacterial strain has recently been shown to be more sensitive to oxidative stress than other E. coli K-12 strains, revealing a potential role for reactive oxygen species-mediated defenses in the otherwise reduced aphid immune system. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Characterization of the cyn operon in Escherichia coli K12. (United States)

    Sung, Y C; Fuchs, J A


    Escherichia coli can overcome the toxicity of environmental cyanate by hydrolysis of cyanate to ammonia and bicarbonate. This reaction is catalyzed by the enzyme cyanase, encoded by the cynS gene. The nucleotide sequence of cynS has been reported (Sung, Y.-c., Anderson, P. M., and Fuchs, J. A. (1987) J. Bacteriol. 169, 5224-5230). The nucleotide sequence of the complete cyn operon has now been determined. The cyn operon is approximately 2600 base pairs and includes cynT, cynS, and cynX, which encode cyanate permease, cyanase, and a protein of unknown function, respectively. Two cyanate-inducible transcripts of 1500 and 2500 nucleotides, respectively, were detected by Northern blot analysis. S1 nuclease mapping experiments indicated that two different cyn mRNAs have a common 5'-end and two different 3'-ends. One 3'-end was located within the coding region of cynX, whereas the other 3'-end includes the entire DNA sequence of cynX. The longer transcript contained 98 nucleotides complementary to lac mRNA produced by the predominant lac transcription termination sequence. Termination vectors were used to show that both 3'-ends were generated by sequences that caused transcriptional termination in vivo. Expression vectors were used to demonstrate that a protein corresponding to the expected size was synthesized from the DNA fragment containing the open reading frame designated cynX. The predicted amino acid sequence of cynX indicates that it is a very hydrophobic protein. The level of cynX expression was significantly less than that of cynT or cynS expression.

  6. Characterization of pyruvate uptake in Escherichia coli K-12.

    Directory of Open Access Journals (Sweden)

    Jens Kreth

    Full Text Available The monocarboxylate pyruvate is an important metabolite and can serve as sole carbon source for Escherichia coli. Although specific pyruvate transporters have been identified in two bacterial species, pyruvate transport is not well understood in E. coli. In the present study, pyruvate transport was investigated under different growth conditions. The transport of pyruvate shows specific activities depending on the growth substrate used as sole carbon source, suggesting the existence of at least two systems for pyruvate uptake: i one inducible system and probably highly specific for pyruvate and ii one system active under non-induced conditions. Using the toxic pyruvate analog 3-fluoropyruvate, a mutant was isolated unable to grow on and transport pyruvate. Further investigation revealed that a revertant selected for growth on pyruvate regained the inducible pyruvate transport activity. Characterization of pyruvate excretion showed that the pyruvate transport negative mutant accumulated pyruvate in the growth medium suggesting an additional transport system for pyruvate excretion. The here presented data give valuable insight into the pyruvate metabolism and transport of E. coli suggesting the presence of at least two uptake systems and one excretion system to balance the intracellular level of pyruvate.

  7. Effects of sound exposure on the growth and intracellular macromolecular synthesis of E. coli k-12

    Directory of Open Access Journals (Sweden)

    Shaobin Gu


    Full Text Available Microbes, as one of the primary producers of the biosphere, play an important role in ecosystems. Exploring the mechanism of adaptation and resistance of microbial population to various environmental factors has come into focus in the fields of modern microbial ecology and molecular ecology. However, facing the increasingly serious problem of acoustic pollution, very few efforts have been put forth into studying the relation of single cell organisms and sound field exposure. Herein, we studied the biological effects of sound exposure on the growth of E. coli K-12 with different acoustic parameters. The effects of sound exposure on the intracellular macromolecular synthesis and cellular morphology of E. coli K-12 were also analyzed and discussed. Experimental results indicated that E. coli K-12 exposed to sound waves owned a higher biomass and a faster specific growth rate compared to the control group. Also, the average length of E. coli K-12 cells increased more than 27.26%. The maximum biomass and maximum specific growth rate of the stimulation group by 8000 Hz, 80dB sound wave was about 1.7 times and 2.5 times that of the control group, respectively. Moreover, it was observed that E. coli K-12 can respond rapidly to sound stress at both the transcriptional and posttranscriptional levels by promoting the synthesis of intracellular RNA and total protein. Some potential mechanisms may be involved in the responses of bacterial cells to sound stress.

  8. PEF based hurdle strategy to control Pichia fermentans, Listeria innocua and Escherichia coli k12 in orange juice. (United States)

    McNamee, C; Noci, F; Cronin, D A; Lyng, J G; Morgan, D J; Scannell, A G M


    The combination of pulsed electric fields (PEF) and bacteriocins in a hurdle approach has been reported to enhance microbial inactivation. This study investigates the preservation of orange juice using PEF in combination with nisin (2.5 ppm), natamycin (10 ppm), benzoic acid (BA; 100 ppm), or lactic acid, (LA; 500 ppm). Pichia fermentans, a spoilage yeast frequently isolated from orange juice, Escherichia coli k12 or Listeria innocua were inoculated into sterile orange juice (OJ) with, and without, added preservatives. The antimicrobial activity over time was evaluated relative to an untreated control. The effect of PEF treatment (40 kV/cm, 100 micros; max temperature 56 degrees C) was assessed on its own, and in combination with each antimicrobial. The acidic environment of OJ inactivated E. coli k12 (1.5log reduction) and L. innocua (0.7log reduction) slightly but had no effect on P. fermentans. PEF caused a significant decrease (PPEF inactivated L. innocua and E. coli k12 in a synergistic manner resulting in a total reduction to 5.6 and 7.9log respectively. A similar synergy was shown between LA and PEF in the inactivation of L. innocua and P. fermentans (6.1 and 7.8log reduction), but not E. coli k12. The BA-PEF combination caused an additive inactivation of P. fermentans, whereas the natamycin-PEF combination against P. fermentans was not significantly different to the effect caused by PEF alone. This study shows that combining PEF with the chosen preservatives, at levels lower than those in current use, can provide greater than 5log reductions of E. coli k12, L. innocua and P. fermentans in OJ. These PEF-bio-preservative combination hurdles could provide the beverage industry with effective non-thermal alternatives to prevent microbial spoilage, and improve the safety of fruit juice. Copyright 2009 Elsevier B.V. All rights reserved.

  9. Molecular cloning and expression of Treponema pallidum DNA in Escherichia coli K12.

    NARCIS (Netherlands)

    J.D.A. van Embden; H.J.M. van de Donk; R.V.W. van Eijk (Ron); H.G. v.d. Heide; J.A. de Jong (Jan); M.F. van Olderen; A.D.M.E. Osterhaus (Albert); L.M. Schouls


    textabstractA gene bank of Treponema pallidum DNA in Escherichia coli K-12 was constructed by cloning SauI-cleaved T. pallidum DNA into the cosmid pHC79. Sixteen of 800 clones investigated produced one or more antigens that reacted with antibodies from syphilitic patients. According to the

  10. Attachment behaviour of Escherichia coli K12 and Salmonella Typhimurium P6on food contact surfaces for food transportation

    DEFF Research Database (Denmark)

    Abban, Stephen; Jakobsen, Mogens; Jespersen, Lene


    . Typhimurium P6 respectively. Correlation with roughness average was poor; r = -0.425 and -0.413 respectively for E. coli K12 and S. Typhimurium P6. Presence of residue caused significant reduction (p bacteria attached to all materials, but made attached bacteria significantly more...... difficult to detach by either of two rinsing systems from all three surfaces. Explanation for these observations could be made in part from scanning electron micrographs which showed significantly more bacteria sitting on patches of residue when it was introduced to the surfaces, compared to the bare...... material sections of the same surfaces. We report these observations for the first time for aluminium and the FRP material and in part for stainless steel. The S. Typhimurium P6 strain also had significantly higher level of attachment than the E. coli K12 strain. Our findings show that food residue...

  11. Characterization of the specific pyruvate transport system in Escherichia coli K-12.


    Lang, V J; Leystra-Lantz, C; Cook, R A


    A mutant of Escherichia coli K-12 lacking pyruvate dehydrogenase and phosphoenolpyruvate synthase was used to study the transport of pyruvate by whole cells. Uptake of pyruvate was maximal in mid-log phase cells, with a Michaelis constant for transport of 20 microM. Pretreatment of the cells with respiratory chain poisons or uncouplers, except for arsenate, inhibited transport up to 95%. Lactate and alanine were competitive inhibitors, but at nonphysiological concentrations. The synthetic ana...

  12. Global impact of mature biofilm lifestyle on Escherichia coli K-12 gene expression

    DEFF Research Database (Denmark)

    Beloin, C.; Valle, J.; Latour-Lambert, P.


    The formation of biofilm results in a major lifestyle switch that is thought to affect the expression of multiple genes and operons. We used DNA arrays to study the global effect of biofilm formation on gene expression in mature Escherichia coli K-12 biofilm. We show that, when biofilm is compared...... that 20 of these genes are required for the formation of mature biofilm. This group includes 11 genes of previously unknown function. These results constitute a comprehensive analysis of the global transcriptional response triggered in mature E. coli biofilms and provide insights into its physiological...

  13. Attachment behaviour of Escherichia coli K12 and Salmonella Typhimurium P6 on food contact surfaces for food transportation. (United States)

    Abban, Stephen; Jakobsen, Mogens; Jespersen, Lene


    The role of cargo container lining materials aluminium, a fibre reinforced plastic (FRP) and stainless steel in bacterial cross contamination during transport was assessed. For this, attachment and detachment of Escherichia coli K12 and Salmonella Typhimurium P6 on the three surfaces in the absence or presence of residues were evaluated. Observations were correlated with water contact angles of the materials (hydrophobicity) and roughness profile (R(a)). Attachment of the organisms was negatively correlated to the hydrophobicity of the three materials with r = -0.869 and -0.861 for E. coli K12 and S. Typhimurium P6 respectively. Correlation with roughness average was poor; r = -0.425 and -0.413 respectively for E. coli K12 and S. Typhimurium P6. Presence of residue caused significant reduction (p food residue and soils affect the extent and amount of bacteria attaching to abiotic surfaces by altering the surface contact properties for the bacteria. Physicochemical properties like hydrophobicity appear to be a better basis for material selection for hygienic design of containers, than the traditional use of R(a). Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Characterization of the specific pyruvate transport system in Escherichia coli K-12. (United States)

    Lang, V J; Leystra-Lantz, C; Cook, R A


    A mutant of Escherichia coli K-12 lacking pyruvate dehydrogenase and phosphoenolpyruvate synthase was used to study the transport of pyruvate by whole cells. Uptake of pyruvate was maximal in mid-log phase cells, with a Michaelis constant for transport of 20 microM. Pretreatment of the cells with respiratory chain poisons or uncouplers, except for arsenate, inhibited transport up to 95%. Lactate and alanine were competitive inhibitors, but at nonphysiological concentrations. The synthetic analogs 3-bromopyruvate and pyruvic acid methyl ester inhibited competitively. The uptake of pyruvate was also characterized in membrane vesicles from wild-type E. coli K-12. Transport required an artificial electron donor system, phenazine methosulfate and sodium ascorbate. Pyruvate was concentrated in vesicles 7- to 10-fold over the external concentration, with a Michaelis constant of 15 microM. Energy poisons, except arsenate, inhibited the transport of pyruvate. Synthetic analogs such as 3-bromopyruvate were competitive inhibitors of transport. Lactate initially appeared to be a competitive inhibitor of pyruvate transport in vesicles, but this was a result of oxidation of lactate to pyruvate. The results indicate that uptake of pyruvate in E. coli is via a specific active transport system.

  15. Biochemical and genetic characterization of a carbamyl phosphate synthetase mutant of Escherichia coli K12. (United States)

    Bolivar, F; Galván, M; Martuscelli, J


    An unusual Escherichia coli K12 mutant for carbamyl phosphate synthetase is described. The mutation was generated by bacteriophage MUI insertion and left a 5% residual activity of the enzyme using either ammonia or glutamine as donors. The mutation is recessive to the wild-type allele and maps at or near the pyrA gene, but the mutant requires only arginine and not uracil for growth. By a second block in the pyrB gene it was possible to shift the accumulated carbamyl phosphate to arginine biosynthesis. The Km values and the levels of ornithine activation and inhibition by UMP were normal in the mutant enzyme.

  16. The EcoCyc database: reflecting new knowledge about Escherichia coli K-12. (United States)

    Keseler, Ingrid M; Mackie, Amanda; Santos-Zavaleta, Alberto; Billington, Richard; Bonavides-Martínez, César; Caspi, Ron; Fulcher, Carol; Gama-Castro, Socorro; Kothari, Anamika; Krummenacker, Markus; Latendresse, Mario; Muñiz-Rascado, Luis; Ong, Quang; Paley, Suzanne; Peralta-Gil, Martin; Subhraveti, Pallavi; Velázquez-Ramírez, David A; Weaver, Daniel; Collado-Vides, Julio; Paulsen, Ian; Karp, Peter D


    EcoCyc ( is a freely accessible, comprehensive database that collects and summarizes experimental data for Escherichia coli K-12, the best-studied bacterial model organism. New experimental discoveries about gene products, their function and regulation, new metabolic pathways, enzymes and cofactors are regularly added to EcoCyc. New SmartTable tools allow users to browse collections of related EcoCyc content. SmartTables can also serve as repositories for user- or curator-generated lists. EcoCyc now supports running and modifying E. coli metabolic models directly on the EcoCyc website. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  17. Associations of Escherichia coli K-12 OmpF trimers with rough and smooth lipopolysaccharides

    Energy Technology Data Exchange (ETDEWEB)

    Diedrich, D.L.; Stein, M.A.; Schnaitman, C.A. (Louisiana State Univ. Medical Center, New Orleans (USA))


    The associations of both rough and smooth lipopolysaccharides (LPS) with the OmpF porin of Escherichia coli K-12 were examined in galE strains deleted for ompC. Transformation with pSS37 and growth with galactose conferred the ability to assemble a Shigella dysenteriae O antigen onto the core oligosaccharide of E. coli K-12 LPS. The association of LPS with OmpF trimers was assessed by staining, autoradiography of LPS specifically labeled with (1-14C)galactose, and Western immunoblotting with a monoclonal antibody specific for OmpF trimers. These techniques revealed that the migration distances and multiple banding patterns of OmpF porin trimers in sodium dodecyl sulfate-polyacrylamide gels were dictated by the chemotype of associated LPS. Expression of smooth LPS caused almost all of the trimeric OmpF to run in gels with a slower mobility than trimers from rough strains. The LPS associated with trimers from a smooth strain differed from the bulk-phase LPS by consisting almost exclusively of molecules with O antigen.

  18. GenoBase: comprehensive resource database of Escherichia coli K-12. (United States)

    Otsuka, Yuta; Muto, Ai; Takeuchi, Rikiya; Okada, Chihiro; Ishikawa, Motokazu; Nakamura, Koichiro; Yamamoto, Natsuko; Dose, Hitomi; Nakahigashi, Kenji; Tanishima, Shigeki; Suharnan, Sivasundaram; Nomura, Wataru; Nakayashiki, Toru; Aref, Walid G; Bochner, Barry R; Conway, Tyrrell; Gribskov, Michael; Kihara, Daisuke; Rudd, Kenneth E; Tohsato, Yukako; Wanner, Barry L; Mori, Hirotada


    Comprehensive experimental resources, such as ORFeome clone libraries and deletion mutant collections, are fundamental tools for elucidation of gene function. Data sets by omics analysis using these resources provide key information for functional analysis, modeling and simulation both in individual and systematic approaches. With the long-term goal of complete understanding of a cell, we have over the past decade created a variety of clone and mutant sets for functional genomics studies of Escherichia coli K-12. We have made these experimental resources freely available to the academic community worldwide. Accordingly, these resources have now been used in numerous investigations of a multitude of cell processes. Quality control is extremely important for evaluating results generated by these resources. Because the annotation has been changed since 2005, which we originally used for the construction, we have updated these genomic resources accordingly. Here, we describe GenoBase (, which contains key information about comprehensive experimental resources of E. coli K-12, their quality control and several omics data sets generated using these resources. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  19. Regulatory role of XynR (YagI) in catabolism of xylonate in Escherichia coli K-12. (United States)

    Shimada, Tomohiro; Momiyama, Eri; Yamanaka, Yuki; Watanabe, Hiroki; Yamamoto, Kaneyoshi; Ishihama, Akira


    The genome of Escherichia coli K-12 contains ten cryptic phages, altogether constituting about 3.6% of the genome in sequence. Among more than 200 predicted genes in these cryptic phages, 14 putative transcription factor (TF) genes exist, but their regulatory functions remain unidentified. As an initial attempt to make a breakthrough for understanding the regulatory roles of cryptic phage-encoded TFs, we tried to identify the regulatory function of CP4-6 cryptic prophage-encoded YagI with unknown function. After SELEX screening, YagI was found to bind mainly at a single site within the spacer of bidirectional transcription units, yagA (encoding another uncharacterized TF) and yagEF (encoding 2-keto-3-deoxy gluconate aldolase, and dehydratase, respectively) within this prophage region. YagEF enzymes are involved in the catabolism of xylose downstream from xylonate. We then designated YagI as XynR (regulator of xylonate catabolism), one of the rare single-target TFs. In agreement with this predicted regulatory function, the activity of XynR was suggested to be controlled by xylonate. Even though low-affinity binding sites of XynR were identified in the E. coli K-12 genome, they all were inside open reading frames, implying that the regulation network of XynR is still fixed within the CR4-6 prophage without significant influence over the host E. coli K-12. © FEMS 2017. All rights reserved. For permissions, please e-mail:

  20. Antigen 43 and type 1 fimbriae determine colony morphology of Escherichia coli K-12

    DEFF Research Database (Denmark)

    Hasman, Henrik; Schembri, Mark; Klemm, Per


    Colony morphology has been used as an important identification and characterization criterion in bacteriology for many decades. However, the molecular mechanisms underlying the appearance of different colony types have been given little attention. The synthesis of O antigen is defunct in Escheric......Colony morphology has been used as an important identification and characterization criterion in bacteriology for many decades. However, the molecular mechanisms underlying the appearance of different colony types have been given little attention. The synthesis of O antigen is defunct...... in Escherichia coli K-12, and colonies should accordingly only appear to be rough. However, previous reports have noted the presence of different interchangeable colony morphology types. In this study we have addressed the influence of two phase-variable surface structures, antigen 43 and type 1 fimbriae...

  1. The UDP-glucose dehydrogenase of Escherichia coli K-12 displays substrate inhibition by NAD that is relieved by nucleotide triphosphates. (United States)

    Mainprize, Iain L; Bean, Jordan D; Bouwman, Catrien; Kimber, Matthew S; Whitfield, Chris


    UDP-glucose dehydrogenase (Ugd) generates UDP-glucuronic acid, an important precursor for the production of many hexuronic acid-containing bacterial surface glycostructures. In Escherichia coli K-12, Ugd is important for biosynthesis of the environmentally regulated exopolysaccharide known as colanic acid, whereas in other E. coli isolates, the same enzyme is required for production of the constitutive group 1 capsular polysaccharides, which act as virulence determinants. Recent studies have implicated tyrosine phosphorylation in the activation of Ugd from E. coli K-12, although it is not known if this is a feature shared by bacterial Ugd proteins. The activities of Ugd from E. coli K-12 and from the group 1 capsule prototype (serotype K30) were compared. Surprisingly, for both enzymes, site-directed Tyr → Phe mutants affecting the previously proposed phosphorylation site retained similar kinetic properties to the wild-type protein. Purified Ugd from E. coli K-12 had significant levels of NAD substrate inhibition, which could be alleviated by the addition of ATP and several other nucleotide triphosphates. Mutations in a previously identified UDP-glucuronic acid allosteric binding site decreased the binding affinity of the nucleotide triphosphate. Ugd from E. coli serotype K30 was not inhibited by NAD, but its activity still increased in the presence of ATP.

  2. Gene envY of Escherichia coli K-12 affects thermoregulation of major porin expression. (United States)

    Lundrigan, M D; Earhart, C F


    The temperature-dependent expression of OmpF and OmpC, the major channel-forming proteins of the Escherichia coli K-12 outer membrane, was studied. In wild-type cells, decreasing growth temperatures resulted in increased amounts of OmpF protein and correspondingly decreased quantities of OmpC protein. Bacteria deleted for the 13-min chromosomal region did not exhibit this temperature-dependent fluctuation in porin proteins. Plasmid pML22, which consists of pBR322 containing a 0.5-megadalton E. coli chromosomal DNA insert, complemented the thermoregulatory defect. The regulatory gene was named envY. In minicells, pML22 directed the synthesis of an envelope polypeptide (EnvY) having an apparent molecular weight of 25,000. The EnvY protein was synthesized in minicells in greater amounts at 27 degrees C than at 37 degrees C, and a reducing agent was necessary in the solubilization buffer for its subsequent detection on polyacrylamide gels. The results describe the initial characterization of a regulatory system which, along with proteins of the ompB operon, the cyclic AMP system, and the tolC gene product, is involved in a complex network affecting major porin expression. Images PMID:6317653

  3. Sulphoglycolysis in Escherichia coli K-12 closes a gap in the biogeochemical sulphur cycle. (United States)

    Denger, Karin; Weiss, Michael; Felux, Ann-Katrin; Schneider, Alexander; Mayer, Christoph; Spiteller, Dieter; Huhn, Thomas; Cook, Alasdair M; Schleheck, David


    Sulphoquinovose (SQ, 6-deoxy-6-sulphoglucose) has been known for 50 years as the polar headgroup of the plant sulpholipid in the photosynthetic membranes of all higher plants, mosses, ferns, algae and most photosynthetic bacteria. It is also found in some non-photosynthetic bacteria, and SQ is part of the surface layer of some Archaea. The estimated annual production of SQ is 10,000,000,000 tonnes (10 petagrams), thus it comprises a major portion of the organo-sulphur in nature, where SQ is degraded by bacteria. However, despite evidence for at least three different degradative pathways in bacteria, no enzymic reaction or gene in any pathway has been defined, although a sulphoglycolytic pathway has been proposed. Here we show that Escherichia coli K-12, the most widely studied prokaryotic model organism, performs sulphoglycolysis, in addition to standard glycolysis. SQ is catabolised through four newly discovered reactions that we established using purified, heterologously expressed enzymes: SQ isomerase, 6-deoxy-6-sulphofructose (SF) kinase, 6-deoxy-6-sulphofructose-1-phosphate (SFP) aldolase, and 3-sulpholactaldehyde (SLA) reductase. The enzymes are encoded in a ten-gene cluster, which probably also encodes regulation, transport and degradation of the whole sulpholipid; the gene cluster is present in almost all (>91%) available E. coli genomes, and is widespread in Enterobacteriaceae. The pathway yields dihydroxyacetone phosphate (DHAP), which powers energy conservation and growth of E. coli, and the sulphonate product 2,3-dihydroxypropane-1-sulphonate (DHPS), which is excreted. DHPS is mineralized by other bacteria, thus closing the sulphur cycle within a bacterial community.

  4. Precise determinations of C and D periods by flow cytometry in Escherichia coli K-12 and B/r

    DEFF Research Database (Denmark)

    Michelsen, Ole; de Mattos, M.J.T.; Jensen, Peter Ruhdal


    The C and D cell cycle periods of seven Escherichia coli K-12 strains and three E, coli B/r strains were determined by computer simulation of DNA histograms obtained by flow cytometry of batch cultures grown at several different generation times. To obtain longer generation times two of the K-12...... generation times. In glucose-limited chemostats good correlation was found between D periods and generation times, whereas batch cultures exhibited carbon-source-dependent variations. Chemostat cultures showed cell cycle variations very similar to those obtained in batch cultures. These flow cytometric...

  5. Mechanism for nitrogen isotope fractionation during ammonium assimilation by Escherichia coli K12 (United States)

    Vo, Jason; Inwood, William; Hayes, John M.; Kustu, Sydney


    Organisms that use ammonium as the sole nitrogen source discriminate between [15N] and [14N] ammonium. This selectivity leaves an isotopic signature in their biomass that depends on the external concentration of ammonium. To dissect how differences in discrimination arise molecularly, we examined a wild-type (WT) strain of Escherichia coli K12 and mutant strains with lesions affecting ammonium-assimilatory proteins. We used isotope ratio mass spectrometry (MS) to assess the nitrogen isotopic composition of cell material when the strains were grown in batch culture at either high or low external concentrations of NH3 (achieved by controlling total NH4Cl and pH of the medium). At high NH3 (≥0.89 µM), discrimination against the heavy isotope by the WT strain (−19.2‰) can be accounted for by the equilibrium isotope effect for dissociation of NH4+ to NH3 + H+. NH3 equilibrates across the cytoplasmic membrane, and glutamine synthetase does not manifest an isotope effect in vivo. At low NH3 (≤0.18 µM), discrimination reflects an isotope effect for the NH4+ channel AmtB (−14.1‰). By making E. coli dependent on the low-affinity ammonium-assimilatory pathway, we determined that biosynthetic glutamate dehydrogenase has an inverse isotope effect in vivo (+8.8‰). Likewise, by making unmediated diffusion of NH3 across the cytoplasmic membrane rate-limiting for cell growth in a mutant strain lacking AmtB, we could deduce an in vivo isotope effect for transport of NH3 across the membrane (−10.9‰). The paper presents the raw data from which our conclusions were drawn and discusses the assumptions underlying them. PMID:23650377

  6. Mechanism for nitrogen isotope fractionation during ammonium assimilation by Escherichia coli K12. (United States)

    Vo, Jason; Inwood, William; Hayes, John M; Kustu, Sydney


    Organisms that use ammonium as the sole nitrogen source discriminate between [(15)N] and [(14)N] ammonium. This selectivity leaves an isotopic signature in their biomass that depends on the external concentration of ammonium. To dissect how differences in discrimination arise molecularly, we examined a wild-type (WT) strain of Escherichia coli K12 and mutant strains with lesions affecting ammonium-assimilatory proteins. We used isotope ratio mass spectrometry (MS) to assess the nitrogen isotopic composition of cell material when the strains were grown in batch culture at either high or low external concentrations of NH3 (achieved by controlling total NH4Cl and pH of the medium). At high NH3 (≥ 0.89 µM), discrimination against the heavy isotope by the WT strain (-19.2‰) can be accounted for by the equilibrium isotope effect for dissociation of NH4(+) to NH3 + H(+). NH3 equilibrates across the cytoplasmic membrane, and glutamine synthetase does not manifest an isotope effect in vivo. At low NH3 (≤ 0.18 µM), discrimination reflects an isotope effect for the NH4(+) channel AmtB (-14.1‰). By making E. coli dependent on the low-affinity ammonium-assimilatory pathway, we determined that biosynthetic glutamate dehydrogenase has an inverse isotope effect in vivo (+8.8‰). Likewise, by making unmediated diffusion of NH3 across the cytoplasmic membrane rate-limiting for cell growth in a mutant strain lacking AmtB, we could deduce an in vivo isotope effect for transport of NH3 across the membrane (-10.9‰). The paper presents the raw data from which our conclusions were drawn and discusses the assumptions underlying them.

  7. YbiV from E. coli K12 is a HAD phosphatase

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, Anne; Lee, Seok-Yong; McCullagh, Emma; Silversmith, Ruth E.; Wemmer, David E.


    The protein YbiV from Escherichia coli K12 MG1655 is a hypothetical protein with sequence homology to the haloacid dehalogenase (HAD) superfamily of proteins. Although numerous members of this family have been identified, the functions of few are known. Using the crystal structure, sequence analysis, and biochemical assays, we have characterized ybiV as a HAD phosphatase. The crystal structure of YbiV reveals a two domain protein, one with the characteristic HAD hydrolase fold, the other an inserted a/b fold. In an effort to understand the mechanism we also solved and report the structures of YbiV in complex with beryllofluoride (BeF3-) and aluminum trifluoride (AlF3) which have been shown to mimic the phosphorylated intermediate and transition state for hydrolysis, respectively, in analogy to other HAD phosphatases. Analysis of the structures reveals the substrate binding cavity, which is hydrophilic in nature. Both structure and sequence homology indicate ybiV may be a sugar phosphatase, which is supported by biochemical assays which measured the release of free phosphate on a number of sugar-like substrates. We also investigated available genomic and functional data in an effort to determine the physiological substrate.


    Pittard, James; Adelberg, Edward A.


    Pittard, James (Yale University, New Haven, Conn.) and Edward A. Adelberg. Gene transfer by F′ strains of Escherichia coli K-12. II. Interaction between F-merogenote and chromosome during transfer. J. Bacteriol. 85:1402–1408. 1963.—When F′ strains harboring the F-merogenate F14 are mated with female recipients, the transfer of the F-merogenote begins, in the majority of cases, before chromosome transfer. The markers on F14 are transferred in the sequence met-1, arg-1, ilva-16, and sex-factor, met-1 being transferred first and sex-factor being transferred last, 9 min after met-1. In the class of zygotes that have received both the F-merogenote marker met-1 and the chromosomal marker xyl or mal, the gradient of recombination frequencies for the F-merogenote markers arg-1 and ilva-16 is much steeper than in the corresponding zygotes that have not received chromosomal markers. In F′ strains which exhibit an increased frequency of transfer of chromosome markers, this gradient of recombination frequencies for merogenote markers is much steeper. An analysis of experiments involving an F′ strain with a much shorter F-merogenote, F16, and of a triparental mating in which F-merogenote and chromosome were transferred from different donor cells reveals that the effect of chromosome transfer on the recovery of distal F-merogenote markers in the zygotes is not due to any form of postzygotic elimination. It is suggested that, when F′ strains which are transferring F-merogenote begin to transfer chromosome, the latter event causes breakage of the F-merogenote. A second consequence of this interaction is a delay of 8 to 10 min in the first appearance of chromosomal markers in the zygotes. PMID:14047236

  9. Membrane damage and viability loss of Escherichia coli K-12 and Salmonella enteritidis in liquid egg by thermal death time disk treatment. (United States)

    Ukuku, Dike O; Jin, Tony; Zhang, Howard


    Bacterial injury, including leakage of intracellular substance and viability loss, of Escherichia coli K-12 (ATCC 23716) and Salmonella Enteritidis (ATCC 13076) inoculated in liquid egg white and liquid whole egg was determined by thermal death time disk. E. coli K-12 and Salmonella Enteritidis were inoculated in liquid egg white and liquid whole egg to a final count of 7.8 log CFU/ml and were thermally treated with thermal death time disks at room temperature (23"C), 54, 56, 58, and 60 degrees C from 0 to 240 s. Sublethal injury, leakage of intracellular substances, and viability loss of E. coli K-12 and Salmonella Enteritidis was investigated by plating 0.1 ml on selective trypticase soy agar containing 3% NaCl, 5% NaCl, sorbitol MacConky agar, and xylose lysine sodium tetradecylsulfate and nonselective trypticase soy agar. No significant (P > 0.05) differences on percent injury or viability loss for E. coli K-12 and Salmonella populations were determined in all samples treated at 23 degrees C. Sublethal injury occurred in E. coli and Salmonella populations at 54 degrees C or above for 120 s. Viability losses for both bacteria averaged 5 log at 54 degrees C or above for 180 s, and the surviving populations were below detection (membrane damage, leakage, and accumulation of intracellular ATP from 2 to 2.5 log fg/ml and UV-absorbing substances of 0.1 to 0.39 in the treated samples. These results indicate similar thermal injury/damage on both E. coli and Salmonella membranes as determined by the amount of inactivation, viability loss, and leakage of intracellular substances of bacteria.

  10. Fast growth phenotype of E. coli K-12 from adaptive laboratory evolution does not require intracellular flux rewiring

    DEFF Research Database (Denmark)

    Long, Christopher P.; Gonzalez, Jacqueline E.; Feist, Adam M.


    Adaptive laboratory evolution (ALE) is a widely-used method for improving the fitness of microorganisms in selected environmental conditions. It has been applied previously to Escherichia coli K-12 MG1655 during aerobic exponential growth on glucose minimal media, a frequently used model organism...... principal components. The distance between measured and flux balance analysis predicted fluxes was also investigated. It suggested a relatively wide range of similar stoichiometric optima, which opens new questions about the path-dependency of adaptive evolution....

  11. Complete Genome Sequence of ER2796, a DNA Methyltransferase-Deficient Strain of Escherichia coli K-12.

    Directory of Open Access Journals (Sweden)

    Brian P Anton

    Full Text Available We report the complete sequence of ER2796, a laboratory strain of Escherichia coli K-12 that is completely defective in DNA methylation. Because of its lack of any native methylation, it is extremely useful as a host into which heterologous DNA methyltransferase genes can be cloned and the recognition sequences of their products deduced by Pacific Biosciences Single-Molecule Real Time (SMRT sequencing. The genome was itself sequenced from a long-insert library using the SMRT platform, resulting in a single closed contig devoid of methylated bases. Comparison with K-12 MG1655, the first E. coli K-12 strain to be sequenced, shows an essentially co-linear relationship with no major rearrangements despite many generations of laboratory manipulation. The comparison revealed a total of 41 insertions and deletions, and 228 single base pair substitutions. In addition, the long-read approach facilitated the surprising discovery of four gene conversion events, three involving rRNA operons and one between two cryptic prophages. Such events thus contribute both to genomic homogenization and to bacteriophage diversification. As one of relatively few laboratory strains of E. coli to be sequenced, the genome also reveals the sequence changes underlying a number of classical mutant alleles including those affecting the various native DNA methylation systems.

  12. Acid Evolution of Escherichia coli K-12 Eliminates Amino Acid Decarboxylases and Reregulates Catabolism. (United States)

    He, Amanda; Penix, Stephanie R; Basting, Preston J; Griffith, Jessie M; Creamer, Kaitlin E; Camperchioli, Dominic; Clark, Michelle W; Gonzales, Alexandra S; Chávez Erazo, Jorge Sebastian; George, Nadja S; Bhagwat, Arvind A; Slonczewski, Joan L


    Acid-adapted strains of Escherichia coli K-12 W3110 were obtained by serial culture in medium buffered at pH 4.6 (M. M. Harden, A. He, K. Creamer, M. W. Clark, I. Hamdallah, K. A. Martinez, R. L. Kresslein, S. P. Bush, and J. L. Slonczewski, Appl Environ Microbiol 81:1932-1941, 2015, Revised genomic analysis of these strains revealed insertion sequence (IS)-driven insertions and deletions that knocked out regulators CadC (acid induction of lysine decarboxylase), GadX (acid induction of glutamate decarboxylase), and FNR (anaerobic regulator). Each acid-evolved strain showed loss of one or more amino acid decarboxylase systems, which normally help neutralize external acid (pH 5 to 6) and increase survival in extreme acid (pH 2). Strains from populations B11, H9, and F11 had an IS 5 insertion or IS-mediated deletion in cadC , while population B11 had a point mutation affecting the arginine activator adiY The cadC and adiY mutants failed to neutralize acid in the presence of exogenous lysine or arginine. In strain B11-1, reversion of an rpoC (RNA polymerase) mutation partly restored arginine-dependent neutralization. All eight strains showed deletion or downregulation of the Gad acid fitness island. Strains with the Gad deletion lost the ability to produce GABA (gamma-aminobutyric acid) and failed to survive extreme acid. Transcriptome sequencing (RNA-seq) of strain B11-1 showed upregulated genes for catabolism of diverse substrates but downregulated acid stress genes (the biofilm regulator ariR , yhiM , and Gad). Other strains showed downregulation of H 2 consumption mediated by hydrogenases ( hya and hyb ) which release acid. Strains F9-2 and F9-3 had a deletion of fnr and showed downregulation of FNR-dependent genes ( dmsABC , frdABCD , hybABO , nikABCDE , and nrfAC ). Overall, strains that had evolved in buffered acid showed loss or downregulation of systems that neutralize unbuffered acid and showed altered regulation of

  13. An Investigative Study on the Effect of Silver Nanoparticles on E.Coli K12 in Various Sodium Chloride Concentrations (United States)

    Levard, C.; Mitra, S.; Badireddy, A.; Jew, A. D.; Brown, G. E.


    Engineered nanomaterials have had an increasing presence in consumer products. Consequently, their release in wastewater systems is believed to pose a viable threat to the environment. NPs are used for drug delivery devices, imaging agents, and consumer products like sunscreens, paints, and cosmetics. Among the major types of manufactured nanoparticles, silver nanoparticles (Ag-NPs) are currently the most widely used in the nanotechnology industry. These particles have unique antibacterial, antiviral, and antifungal properties and as a result, there is a growing concern about the environmental impact of released Ag nanoparticles, particularly their unintended impact on organisms and ecosystems. Even though the toxicity of Ag-NPs has been extensively studied, the environmental transformations that the Ag-NPs may experience once released in the environment have not been considered. These transformations can readily impact their properties and therefore their behavior in terms of reactivity and toxicity. For example, it is known that silver strongly react with Chloride (Cl), which is ubiquitous in natural waters. At a low Cl/Ag ratio, Cl may precipitate on the surface and partly inhibit dissolution. On the contrary, for a high Cl/Ag ratio, chloride may enhance dissolution and therefore toxicity since soluble Ag species are a main source of toxicity. In this context, the focus of this study is on understanding the toxicity of coated Ag-NPs at various concentrations (1ppb-100ppm) on E.Coli (K12) in deionized water and various sodium chloride concentrations that mimic natural conditions (.5, .1 and .01 M NaCl). Ag+ ions (100 ppm-1ppb) were also tested in these salt concentrations as a control. Samples were inoculated in bacteria and incubated for 24 hours. Based on this test, we inferred that increasing concentrations of Ag+ ions/ AgNps played a role in the inhibition of growth of E.Coli K12. A live-dead staining test has shown the correlation between inhibition of

  14. Assisted curation of regulatory interactions and growth conditions of OxyR in E. coli K-12. (United States)

    Gama-Castro, Socorro; Rinaldi, Fabio; López-Fuentes, Alejandra; Balderas-Martínez, Yalbi Itzel; Clematide, Simon; Ellendorff, Tilia Renate; Santos-Zavaleta, Alberto; Marques-Madeira, Hernani; Collado-Vides, Julio


    Given the current explosion of data within original publications generated in the field of genomics, a recognized bottleneck is the transfer of such knowledge into comprehensive databases. We have for years organized knowledge on transcriptional regulation reported in the original literature of Escherichia coli K-12 into RegulonDB (, our database that is currently supported by >5000 papers. Here, we report a first step towards the automatic biocuration of growth conditions in this corpus. Using the OntoGene text-mining system (, we extracted and manually validated regulatory interactions and growth conditions in a new approach based on filters that enable the curator to select informative sentences from preprocessed full papers. Based on a set of 48 papers dealing with oxidative stress by OxyR, we were able to retrieve 100% of the OxyR regulatory interactions present in RegulonDB, including the transcription factors and their effect on target genes. Our strategy was designed to extract, as we did, their growth conditions. This result provides a proof of concept for a more direct and efficient curation process, and enables us to define the strategy of the subsequent steps to be implemented for a semi-automatic curation of original literature dealing with regulation of gene expression in bacteria. This project will enhance the efficiency and quality of the curation of knowledge present in the literature of gene regulation, and contribute to a significant increase in the encoding of the regulatory network of E. coli. RegulonDB Database URL: OntoGene URL: © The Author(s) 2014. Published by Oxford University Press.

  15. Graphene-Based FET Detector for E. coli K12 Real-Time Monitoring and Its Theoretical Analysis

    Directory of Open Access Journals (Sweden)

    Jieyi Zhu


    Full Text Available This paper presents a theoretical analysis for a graphene-based FET real-time detector of the target bacteria E. coli K12. The motivation for this study is to design a sensor device for detection of bacteria in food and water in order to guarantee food safety. Graphene is chosen as our material for sensor design, which has outstanding electrical, physical, and optical performance. In our sensor structure, graphene-based solution gate field effect transistor (FET is the device model; fabrication and functionalization protocol are presented together in this paper. What is more, a real-time signal display system is the accompanied equipment for our designed biosensor device. In this system, the sensor bias current signal Ids would change obviously when the target bacteria are attached to the sensor surface. And the bias current Ids increases when the E. coli concentration increases. In the latter part, a theoretical interpretation of the sensor signal is to explain the bias current Ids increasing after the E. coli K12 attachment.

  16. Metabolic flux balance analysis and the in silico analysis of Escherichia coli K-12 gene deletions

    Directory of Open Access Journals (Sweden)

    Edwards Jeremy S


    Full Text Available Abstract Background Genome sequencing and bioinformatics are producing detailed lists of the molecular components contained in many prokaryotic organisms. From this 'parts catalogue' of a microbial cell, in silico representations of integrated metabolic functions can be constructed and analyzed using flux balance analysis (FBA. FBA is particularly well-suited to study metabolic networks based on genomic, biochemical, and strain specific information. Results Herein, we have utilized FBA to interpret and analyze the metabolic capabilities of Escherichia coli. We have computationally mapped the metabolic capabilities of E. coli using FBA and examined the optimal utilization of the E. coli metabolic pathways as a function of environmental variables. We have used an in silico analysis to identify seven gene products of central metabolism (glycolysis, pentose phosphate pathway, TCA cycle, electron transport system essential for aerobic growth of E. coli on glucose minimal media, and 15 gene products essential for anaerobic growth on glucose minimal media. The in silico tpi-, zwf, and pta- mutant strains were examined in more detail by mapping the capabilities of these in silico isogenic strains. Conclusions We found that computational models of E. coli metabolism based on physicochemical constraints can be used to interpret mutant behavior. These in silica results lead to a further understanding of the complex genotype-phenotype relation. Supplementary information:

  17. Biogenic synthesis and characterization of gold nanoparticles by Escherichia coli K12 and its heterogeneous catalysis in degradation of 4-nitrophenol

    National Research Council Canada - National Science Library

    Srivastava, Sarvesh Kumar; Yamada, Ryosuke; Ogino, Chiaki; Kondo, Akihiko


    Room-temperature extracellular biosynthesis of gold nanoparticles (Au NPs) was achieved using Escherichia coli K12 cells without the addition of growth media, pH adjustments or inclusion of electron donors/stabilizing agents...

  18. Functional analysis of the large periplasmic loop of the Escherichia coli K-12 WaaL O-antigen ligase. (United States)

    Pérez, José M; McGarry, Megan A; Marolda, Cristina L; Valvano, Miguel A


    WaaL is a membrane enzyme implicated in ligating undecaprenyl-diphosphate (Und-PP)-linked O antigen to lipid A-core oligosaccharide. We determined the periplasmic location of a large (EL5) and small (EL4) adjacent loops in the Escherichia coli K-12 WaaL. Structural models of the EL5 from the K-12, R1 and R4 E. coli ligases were generated by molecular dynamics. Despite the poor amino acid sequence conservation among these proteins, the models afforded similar folds consisting of two pairs of almost perpendicular alpha-helices. One alpha-helix in each pair contributes a histidine and an arginine facing each other, which are highly conserved in WaaL homologues. Mutations in either residue rendered WaaL non-functional, since mutant proteins were unable to restore O antigen surface expression. Replacements of residues located away from the putative catalytic centre and non-conserved residues within the centre itself did not affect ligation. Furthermore, replacing a highly conserved arginine in EL4 with various amino acids inactivates WaaL function, but functionality reappears when the positive charge is restored by a replacement with lysine. These results lead us to propose that the conserved amino acids in the two adjacent periplasmic loops could interact with Und-PP, which is the common component in all WaaL substrates.

  19. Identification and characterization of a cyanate permease in Escherichia coli K-12. (United States)

    Sung, Y C; Fuchs, J A


    Escherichia coli contains an inducible enzyme, cyanase, that catalyzes the decomposition of cyanate into ammonia and bicarbonate. The gene encoding cyanase, cynS, was cloned and found to be on a DNA fragment that contained the lac operon. Characterization of a plasmid encoding cyanase indicated that a 26-kilodalton (kDa) protein of unknown function was also induced by cyanate (Y-C. Sung, D. Parsell, P.M. Anderson, and J.A. Fuchs, J. Bacteriol. 169:2639-2642, 1987). The gene encoding the 26-kDa protein was located between cynS and its promoter, indicating the existence of a cyn operon. The 26-kDa protein was identified as a cyanate permease that transports exogenous cyanate by active transport. E. coli was shown to contain a cyanate transport system that is energy dependent and saturable by cyanate.

  20. The Putrescine Importer PuuP of Escherichia coli K-12 (United States)

    Kurihara, Shin; Tsuboi, Yuichi; Oda, Shinpei; Kim, Hyeon Guk; Kumagai, Hidehiko; Suzuki, Hideyuki


    The Puu pathway is a putrescine utilization pathway involving gamma-glutamyl intermediates. The genes encoding the enzymes of the Puu pathway form a gene cluster, the puu gene cluster, and puuP is one of the genes in this cluster. In Escherichia coli, three putrescine importers, PotFGHI, PotABCD, and PotE, were discovered in the 1990s and have been studied; however, PuuP had not been discovered previously. This paper shows that PuuP is a novel putrescine importer whose kinetic parameters are equivalent to those of the polyamine importers discovered previously. A puuP+ strain absorbed up to 5 mM putrescine from the medium, but a ΔpuuP strain did not. E. coli strain MA261 has been used in previous studies of polyamine transporters, but PuuP had not been identified previously. It was revealed that the puuP gene of MA261 was inactivated by a point mutation. When E. coli was grown on minimal medium supplemented with putrescine as the sole carbon or nitrogen source, only PuuP among the polyamine importers was required. puuP was expressed strongly when putrescine was added to the medium or when the puuR gene, which encodes a putative repressor, was deleted. When E. coli was grown in M9-tryptone medium, PuuP was expressed mainly in the exponential growth phase, and PotFGHI was expressed independently of the growth phase. PMID:19181795

  1. The Escherichia coli K-12 gntP gene allows E. coli F-18 to occupy a distinct nutritional niche in the streptomycin-treated mouse large intestine

    DEFF Research Database (Denmark)

    Sweeney, N.J.; Klemm, Per; McCormick, Beth A.


    Escherichia coli F-18 is a human fecal isolate that makes type 1 fimbriae, encoded by the fim gene cluster, and is an excellent colonizer of the streptomycin-treated mouse intestine. E. coli F-18 fimA::tet, lacking type 1 fimbriae, was constructed by bacteriophage P1 transduction of the fim region...... of the E. coli K-12 strain ORN151, containing the tetracycline resistance gene from Tn10 inserted in the fimA gene, into E. coli F-18. E. coli F-18 fimA::tet was found to occupy a distinct niche in the streptomycin-treated mouse intestine when fed in small numbers to mice, along with large numbers of E....... coli K-12 gene responsible for this effect is not fim::tet but gntP, which maps immidiately downstream of the fim gene cluster, are presented. gntP encodes a high-affinity gluconate permease, suggesting that the distinct niche in the mouse large intestine is defined by the presence of gluconate...

  2. The nucleotide sequence of aroG, the gene for 3-deoxy-D-arabinoheptulosonate-7-phosphate synthetase (phe) in Escherichia coli K 12


    Davies, W.David; Davidson, Barrie E.


    We have determined the nucleotide sequence of aroG, the gene coding for 3-deoxy-D-arabinoheptulosonate-7-phosphate synthetase(phe), one of three isoenzymes that catalyse the first step of the biosynthesis of aromatic amino acids and vitamins in Escherichia coli K12. The DNA sequence agrees with previously published data on the N-terminal sequence, amino acid composition, and subunit molecular weight of 3-deoxy-D-arabinoheptulosonate-7-phosphate synthetase(phe). There is significant identity i...

  3. Identification, mapping, and cloning of the gene encoding cyanase in Escherichia coli K-12. (United States)

    Sung, Y C; Parsell, D; Anderson, P M; Fuchs, J A


    The gene in Escherichia coli for cyanase, designated cynS, was localized to a BglII restriction site approximately 1.7 kilobases from the lacA end of the lac operon. The gene was cloned into the pUC13 vector. Maxicell analysis of plasmid-encoded proteins confirmed that the BglII site is in the region encoding the structural gene for cyanase. Cyanase-deficient strains had increased sensitivity to cyanate and were not able to use cyanate as a nitrogen source.

  4. Identification, mapping, and cloning of the gene encoding cyanase in Escherichia coli K-12.


    Sung, Y C; Parsell, D; Anderson, P M; Fuchs, J A


    The gene in Escherichia coli for cyanase, designated cynS, was localized to a BglII restriction site approximately 1.7 kilobases from the lacA end of the lac operon. The gene was cloned into the pUC13 vector. Maxicell analysis of plasmid-encoded proteins confirmed that the BglII site is in the region encoding the structural gene for cyanase. Cyanase-deficient strains had increased sensitivity to cyanate and were not able to use cyanate as a nitrogen source.

  5. Identification and characterization of a cyanate permease in Escherichia coli K-12.


    Sung, Y C; Fuchs, J A


    Escherichia coli contains an inducible enzyme, cyanase, that catalyzes the decomposition of cyanate into ammonia and bicarbonate. The gene encoding cyanase, cynS, was cloned and found to be on a DNA fragment that contained the lac operon. Characterization of a plasmid encoding cyanase indicated that a 26-kilodalton (kDa) protein of unknown function was also induced by cyanate (Y-C. Sung, D. Parsell, P.M. Anderson, and J.A. Fuchs, J. Bacteriol. 169:2639-2642, 1987). The gene encoding the 26-kD...

  6. Metabolic Engineering of Escherichia coli K12 for Homofermentative Production of L-Lactate from Xylose. (United States)

    Jiang, Ting; Zhang, Chen; He, Qin; Zheng, Zhaojuan; Ouyang, Jia


    The efficient utilization of xylose is regarded as a technical barrier to the commercial production of bulk chemicals from biomass. Due to the desirable mechanical properties of polylactic acid (PLA) depending on the isomeric composition of lactate, biotechnological production of lactate with high optical pure has been increasingly focused in recent years. The main objective of this work was to construct an engineered Escherichia coli for the optically pure L-lactate production from xylose. Six chromosomal deletions (pflB, ldhA, ackA, pta, frdA, adhE) and a chromosomal integration of L-lactate dehydrogenase-encoding gene (ldhL) from Bacillus coagulans was involved in construction of E. coli KSJ316. The recombinant strain could produce L-lactate from xylose resulting in a yield of 0.91 g/g xylose. The chemical purity of L-lactate was 95.52%, and the optical purity was greater than 99%. Moreover, three strategies, including overexpression of L-lactate dehydrogenase, intensification of xylose catabolism, and addition of additives to medium, were designed to enhance the production. The results showed that they could increase the concentration of L-lactate by 32.90, 20.13, and 233.88% relative to the control, respectively. This was the first report that adding formate not only could increase the xylose utilization but also led to the fewer by-product levels.

  7. Investigation on the anaerobic propionate degradation by Escherichia coli K12. (United States)

    Simonte, Francesca M; Dötsch, Andreas; Galego, Lisete; Arraiano, Cecilia; Gescher, Johannes


    Propionate is an abundant carboxylic acid in nature. Microorganisms metabolize propionate aerobically via the 2-methylcitrate pathway. This pathway depends on a series of three reactions in the citric acid cycle that leads to the conversion of succinate to oxaloacetate. Interestingly, the γ-proteobacterium Escherichia coli can use propionate as a carbon and electron source under oxic but not under anoxic conditions. RT-PCR and transcriptomic analysis revealed a posttranscriptional regulation of the prpBCDE-gene cluster encoding the necessary enzymes for propionate metabolism. The polycistronic mRNA seems to be hydrolyzed in the 3'-5' direction under anoxic conditions. This regulatory strategy is highly constructive because the last gene of the operon encodes the first enzyme of the propionate metabolism. Further analysis revealed that RNase R is involved in the hydrolysis of the prp transcripts. Consequently, an rnr-deletion strain could metabolize propionate under anoxic conditions. To the best of our knowledge, this is the first study describing the influence of RNase R on the anaerobic metabolism of E. coli. © 2016 John Wiley & Sons Ltd.

  8. Development of an Escherichia coli K12-specific quantitative polymerase chain reaction assay and DNA isolation suited to biofilms associated with iron drinking water pipe corrosion products (United States)

    Escherichia coli is one of the most commonly used fecal indicator organisms for drinking water and groundwater systems. In order to understand various biogeochemical and biophysical factors affecting its interactions with biofilms, E. coli K12 was chosen as a model organism. A Ta...

  9. Immunoglobulin-Mediated Agglutination of and Biofilm Formation by Escherichia coli K-12 Require the Type 1 Pilus Fiber (United States)

    Orndorff, Paul E.; Devapali, Aditya; Palestrant, Sarah; Wyse, Aaron; Everett, Mary Lou; Bollinger, R. Randal; Parker, William


    The binding of human secretory immunoglobulin A (SIgA), the primary immunoglobulin in the gut, to Escherichia coli is thought to be dependent on type 1 pili. Type 1 pili are filamentous bacterial surface attachment organelles comprised principally of a single protein, the product of the fimA gene. A minor component of the pilus fiber (the product of the fimH gene, termed the adhesin) mediates attachment to a variety of host cell molecules in a mannose inhibitable interaction that has been extensively described. We found that the aggregation of E. coli K-12 by human secretory IgA (SIgA) was dependent on the presence of the pilus fiber, even in the absence of the mannose specific adhesin or in the presence of 25 mM α-CH3Man. The presence of pilus without adhesin also facilitated SIgA-mediated biofilm formation on polystyrene, although biofilm formation was stronger in the presence of the adhesin. IgM also mediated aggregation and biofilm formation in a manner dependent on pili with or without adhesin. These findings indicate that the pilus fiber, even in the absence of the adhesin, may play a role in biologically important processes. Under conditions in which E. coli was agglutinated by SIgA, the binding of SIgA to E. coli was not increased by the presence of the pili, with or without adhesin. This observation suggests that the pili, with or without adhesin, affect factors such as cell surface rigidity or electrostatic repulsion, which can affect agglutination but which do not necessarily determine the level of bound immunoglobulin. PMID:15039312

  10. Development of an Escherichia coli K12-specific quantitative polymerase chain reaction assay and DNA isolation suited to biofilms associated with iron drinking water pipe corrosion products. (United States)

    Lu, Jingrang; Gerke, Tammie L; Buse, Helen Y; Ashbolt, Nicholas J


    A quantitative polymerase chain reaction assay (115 bp amplicon) specific to Escherichia coli K12 with an ABI(TM) internal control was developed based on sequence data encoding the rfb gene cluster. Assay specificity was evaluated using three E. coli K12 strains (ATCC W3110, MG1655 & DH1), 24 non-K12 E. coli and 23 bacterial genera. The biofilm detection limit was 10(3) colony-forming units (CFU) E. coli K12 mL(-1), but required a modified protocol, which included a bio-blocker Pseudomonas aeruginosa with ethylenediaminetetraacetic acid buffered to pH 5 prior to cell lysis/DNA extraction. The novel protocol yielded the same sensitivity for drinking water biofilms associated with Fe3O4 (magnetite)-coated SiO2 (quartz) grains and biofilm-surface iron corrosion products from a drinking water distribution system. The novel DNA extraction protocol and specific E. coli K12 assay are sensitive and robust enough for detection and quantification within iron drinking water pipe biofilms, and are particularly well suited for studying enteric bacterial interactions within biofilms.

  11. Transformation of Escherichia coli K-12 with a high-copy plasmid encoding the green fluorescent protein reduces growth: implications for predictive microbiology. (United States)

    Oscar, T P; Dulal, K; Boucaud, D


    The green fluorescent protein (GFP) of the jellyfish Aequorea victoria has been widely used as a biomarker and has potential for use in developing predictive models for growth of pathogens on naturally contaminated food. However, constitutive production of GFP can reduce growth of transformed strains. Consequently, a high-copy plasmid with gfp under the control of a tetracycline-inducible promoter (pTGP) was constructed. The plasmid was first introduced into a tetracycline-resistant strain of Escherichia coli K-12 to propagate it for subsequent transformation of tetracycline-resistant strains of Salmonella. In contrast to transformed E. coli K-12, which only fluoresced in response to tetracycline, transformed Salmonella fluoresced maximally without tetracycline induction of gfp. Although pTGP did not function as intended in Salmonella, growth of parent and GFP E. coli K-12 was compared to test the hypothesis that induction of GFP production reduced growth. Although GFP production was not induced during growth on sterile chicken in the absence of tetracycline, maximum specific growth rate (mumax) of GFP E. coli K-12 was reduced 40 to 50% (P E. coli K-12 was compared in sterile broth at 40 degrees C, mumax and maximum population density of the GFP strain were reduced (P transformation reduced growth of E. coli K-12 independent of gfp induction. Thus, use of a low-copy plasmid or insertion of gfp into the chromosome may be required to construct valid strains for development of predictive models for growth of pathogens on naturally contaminated food.

  12. Bidirectional frequency-dependent effect of extremely low-frequency electromagnetic field on E. coli K-12. (United States)

    Martirosyan, Varsik; Baghdasaryan, Naira; Ayrapetyan, Sinerik


    In the present work, the frequency-dependent effects of extremely low-frequency electromagnetic field (ELF EMF) on Escherichia coli K-12 growth have been studied. The frequency-dependent effects of ELF EMF have shown that it can either stimulate or inhibit the growth of microbes. However, the mechanism by which the ELF EMF affects the bacterial cells is not clear yet. It was suggested that the aqua medium can serve as a target through which the biological effect of ELF EMF on microbes may be realized. To check this hypothesis, the frequency-dependent effects (2, 4, 6, 8, 10 Hz, B = 0.4 mT, 30 min) of ELF EMF on the bacterial growth were studied in both cases where the microbes were in the culture media during the exposure and where culture media was preliminarily exposed to the ELF EMF before the addition of bacteria. For investigating the cell proliferation, the radioactive [(3)H]-thymidine assay was carried out. It has been shown that EMF at 4 Hz exposure has pronounced stimulation while at 8 Hz it has inhibited cell proliferation.

  13. Genes Required for Growth at High Hydrostatic Pressure in Escherichia coli K-12 Identified by Genome-Wide Screening (United States)

    Black, S. Lucas; Dawson, Angela; Ward, F. Bruce; Allen, Rosalind J.


    Despite the fact that much of the global microbial biosphere is believed to exist in high pressure environments, the effects of hydrostatic pressure on microbial physiology remain poorly understood. We use a genome-wide screening approach, combined with a novel high-throughput high-pressure cell culture method, to investigate the effects of hydrostatic pressure on microbial physiology in vivo. The Keio collection of single-gene deletion mutants in Escherichia coli K-12 was screened for growth at a range of pressures from 0.1 MPa to 60 MPa. This led to the identification of 6 genes, rodZ, holC, priA, dnaT, dedD and tatC, whose products were required for growth at 30 MPa and a further 3 genes, tolB, rffT and iscS, whose products were required for growth at 40 MPa. Our results support the view that the effects of pressure on cell physiology are pleiotropic, with DNA replication, cell division, the cytoskeleton and cell envelope physiology all being potential failure points for cell physiology during growth at elevated pressure. PMID:24040140

  14. Cryopreservation of Escherichia coli K12TG1: protection from the damaging effects of supercooling by freezing. (United States)

    Simonin, H; Bergaoui, I M; Perrier-Cornet, J M; Gervais, P


    Injuries in living cells caused by water freezing during a freeze-thaw process have been extensively reported. In particular, intracellular water freezing has long been incriminated in cell death caused by a high cooling rate, but this supposition could not always be demonstrated. This work aims to discriminate the role of water freezing, dehydration and cold-induced injuries in cellular damage occuring during cryopreservation. For this purpose, Escherichia coli K12TG1 suspensions were maintained in a supercooled or frozen state at -20°C for times ranging from 10 min to 5 h. The supercooled state was maintained for a long period at -20°C by applying a non-injurious isostatic pressure (Pfreezing, the survival rate remained high throughout the experiment, and the cell membranes suffered little damage. Moreover, cells subjected to 5h of osmotic treatments at -20°C, conditions that mimic cryoconcentration upon freezing, and subsequently diluted and thawed suffered little damage. Dehydration due to cryoconcentration upon freezing protects the cells against the deleterious effects of supercooling, especially in the plasma membranes. The decrease in membrane leakage upon dehydration at low temperatures could be linked to differences in the gel state of the membrane revealed by a higher Laurdan general polarization (GP) value. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. RegulonDB (version 4.0): transcriptional regulation, operon organization and growth conditions in Escherichia coli K-12. (United States)

    Salgado, Heladia; Gama-Castro, Socorro; Martínez-Antonio, Agustino; Díaz-Peredo, Edgar; Sánchez-Solano, Fabiola; Peralta-Gil, Martín; Garcia-Alonso, Delfino; Jiménez-Jacinto, Verónica; Santos-Zavaleta, Alberto; Bonavides-Martínez, César; Collado-Vides, Julio


    RegulonDB is the primary database of the major international maintained curation of original literature with experimental knowledge about the elements and interactions of the network of transcriptional regulation in Escherichia coli K-12. This includes mechanistic information about operon organization and their decomposition into transcription units (TUs), promoters and their sigma type, binding sites of specific transcriptional regulators (TRs), their organization into 'regulatory phrases', active and inactive conformations of TRs, as well as terminators and ribosome binding sites. The database is complemented with clearly marked computational predictions of TUs, promoters and binding sites of TRs. The current version has been expanded to include information beyond specific mechanisms aimed at gathering different growth conditions and the associated induced and/or repressed genes. RegulonDB is now linked with Swiss-Prot, with microarray databases, and with a suite of programs to analyze and visualize microarray experiments. We provide a summary of the biological knowledge contained in RegulonDB and describe the major changes in the design of the database. RegulonDB can be accessed on the web at the URL:

  16. Analysis of RecA-independent recombination events between short direct repeats related to a genomic island and to a plasmid in Escherichia coli K12

    Directory of Open Access Journals (Sweden)

    María F. Azpiroz


    Full Text Available RecA-independent recombination events between short direct repeats, leading to deletion of the intervening sequences, were found to occur in two genetic models in the Escherichia coli K12 background. The first model was a small E. coli genomic island which had been shown to be mobile in its strain of origin and, when cloned, also in the E. coli K12 context. However, it did not encode a site-specific recombinase as mobile genomic islands usually do. It was then deduced that the host cells should provide the recombination function. This latter was searched for by means of a PCR approach to detect the island excision in E. coli K12 mutants affected in a number of recombination functions, including the 16 E. coli K12 site-specific recombinases, the RecET system, and multiple proteins that participate in the RecA-dependent pathways of homologous recombination. None of these appeared to be involved in the island excision. The second model, analyzed in a RecA deficient context, was a plasmid construction containing a short direct repeat proceeding from Saccharomyces cerevisiae, which flanked the cat gene. The excision of this gene by recombination of the DNA repeats was confirmed by PCR and through the detection, recovery and characterization of the plasmid deleted form. In sum, we present new evidence on the occurrence of RecA-independent recombination events in E. coli K12. Although the mechanism underlying these processes is still unknown, their existence suggests that RecA-independent recombination may confer mobility to other genetic elements, thus contributing to genome plasticity.

  17. Revealing genome-scale transcriptional regulatory landscape of OmpR highlights its expanded regulatory roles under osmotic stress in Escherichia coli K-12 MG1655

    DEFF Research Database (Denmark)

    Seo, Sang Woo; Gao, Ye; Kim, Donghyuk


    A transcription factor (TF), OmpR, plays a critical role in transcriptional regulation of the osmotic stress response in bacteria. Here, we reveal a genome-scale OmpR regulon in Escherichia coli K-12 MG1655. Integrative data analysis reveals that a total of 37 genes in 24 transcription units (TUs...... discoveries related to stress responses....

  18. A comparative analysis of industrial Escherichia coli K-12 and B strains in high-glucose batch cultivations on process-, transcriptome- and proteome level.

    Directory of Open Access Journals (Sweden)

    Karoline Marisch

    Full Text Available Escherichia coli K-12 and B strains are among the most frequently used bacterial hosts for production of recombinant proteins on an industrial scale. To improve existing processes and to accelerate bioprocess development, we performed a detailed host analysis. We investigated the different behaviors of the E. coli production strains BL21, RV308, and HMS174 in response to high-glucose concentrations. Tightly controlled cultivations were conducted under defined environmental conditions for the in-depth analysis of physiological behavior. In addition to acquisition of standard process parameters, we also used DNA microarray analysis and differential gel electrophoresis (Ettan(TM DIGE. Batch cultivations showed different yields of the distinct strains for cell dry mass and growth rate, which were highest for BL21. In addition, production of acetate, triggered by excess glucose supply, was much higher for the K-12 strains compared to the B strain. Analysis of transcriptome data showed significant alteration in 347 of 3882 genes common among all three hosts. These differentially expressed genes included, for example, those involved in transport, iron acquisition, and motility. The investigation of proteome patterns additionally revealed a high number of differentially expressed proteins among the investigated hosts. The subsequently selected 38 spots included proteins involved in transport and motility. The results of this comprehensive analysis delivered a full genomic picture of the three investigated strains. Differentially expressed groups for targeted host modification were identified like glucose transport or iron acquisition, enabling potential optimization of strains to improve yield and process quality. Dissimilar growth profiles of the strains confirm different genotypes. Furthermore, distinct transcriptome patterns support differential regulation at the genome level. The identified proteins showed high agreement with the transcriptome data




    Pittard, James (Yale University, New Haven, Conn.) and Edward A. Adelberg. Gene transfer by F' strains of Escherichia coli K-12. II. Interaction between F-merogenote and chromosome during transfer. J. Bacteriol. 85:1402-1408. 1963.-When F' strains harboring the F-merogenate F(14) are mated with female recipients, the transfer of the F-merogenote begins, in the majority of cases, before chromosome transfer. The markers on F(14) are transferred in the sequence met-1, arg-1, ilva-16, and sex-factor, met-1 being transferred first and sex-factor being transferred last, 9 min after met-1. In the class of zygotes that have received both the F-merogenote marker met-1 and the chromosomal marker xyl or mal, the gradient of recombination frequencies for the F-merogenote markers arg-1 and ilva-16 is much steeper than in the corresponding zygotes that have not received chromosomal markers. In F' strains which exhibit an increased frequency of transfer of chromosome markers, this gradient of recombination frequencies for merogenote markers is much steeper. An analysis of experiments involving an F' strain with a much shorter F-merogenote, F(16), and of a triparental mating in which F-merogenote and chromosome were transferred from different donor cells reveals that the effect of chromosome transfer on the recovery of distal F-merogenote markers in the zygotes is not due to any form of postzygotic elimination. It is suggested that, when F' strains which are transferring F-merogenote begin to transfer chromosome, the latter event causes breakage of the F-merogenote. A second consequence of this interaction is a delay of 8 to 10 min in the first appearance of chromosomal markers in the zygotes.

  20. Characterization of high-level expression and sequencing of the Escherichia coli K-12 cynS gene encoding cyanase. (United States)

    Sung, Y C; Anderson, P M; Fuchs, J A


    Restriction fragments containing the gene encoding cyanase, cynS, without its transcriptional regulatory sequences were placed downstream of lac and tac promoters in various pUC derivatives to maximize production of cyanase. Plasmid pSJ105, which contains the cynS gene and an upstream open reading frame, gave the highest expression of cyanase. Approximately 50% of the total soluble protein in stationary-phase cultures of a lac-deleted strain containing plasmid pSJ105 was cyanase. The inserted DNA fragment of pSJ105 was transferred into pUC18 derivatives that contain a hybrid tac promoter, instead of the lac promoter, and a strong terminator to generate pSJ124. Stationary-phase cultures of JM101 containing plasmid pSJ124 overexpressed a similar level of cyanase. In JM101(pSJ124), maximum production of cyanase could be obtained either by induction with isopropyl-beta-D-thiogalactopyranoside (IPTG) for 3 h or by growth without IPTG into late stationary phase. The latter conditions resulted in a 10- to 20-fold increase in plasmid content and presumably titration of the lac repressor. The nucleotide sequence of the cloned cynS gene from Escherichia coli K-12 was determined. The predicted amino acid sequence differed from the known amino acid sequence of cyanase isolated from a B strain by four residues. However, overexpressed cyanase was purified to homogeneity, and a comparison of the enzymes from the two sources indicated that they did not differ with respect to physical and kinetic properties. The cynS gene was located next to the lac operon, and the direction of cynS transcription was opposite that of lac.

  1. Regulation of 3-Deoxy-d-arabino-Heptulosonic 7-Phosphate Acid Synthetase Activity in Relation to the Synthesis of the Aromatic Vitamins in Escherichia coli K-12 (United States)

    Wallace, B. J.; Pittard, J.


    Both in vivo and in vitro experiments on wild-type Escherichia coli K-12 and mutant strains possessing only single 3-deoxy-d-arabino-heptulosonic 7-phosphate acid (DAHP) synthetase isoenzymes indicated that, under conditions when all three isoenzymes are fully repressed, sufficient chorismate is still formed for the synthesis of aromatic vitamins. Under repressed conditions both DAHP synthetase (phe) and (trp), but not DAHP synthetase (tyr), were shown to contribute to vitamin production. PMID:4905534

  2. Effect of iclR and arcA knockouts on biomass formation and metabolic fluxes in Escherichia coli K12 and its implications on understanding the metabolism of Escherichia coli BL21 (DE3

    Directory of Open Access Journals (Sweden)

    Charlier Daniel


    fluxes. In addition, a comparison of the genome sequences of the two strains showed that BL21 possesses two mutations in the promoter region of iclR and rare codons are present in arcA implying a lower tRNA acceptance. Both phenomena presumably result in a reduced ArcA and IclR synthesis in BL21, which contributes to the similar physiology as observed in E. coli K12 ΔarcAΔiclR. Conclusions The deletion of arcA results in a decrease of repression on transcription of TCA cycle genes under glucose abundant conditions, without significantly affecting the glyoxylate pathway activity. IclR clearly represses transcription of glyoxylate pathway genes under glucose abundance, a condition in which Crp activation is absent. Under glucose limitation, Crp is responsible for the high glyoxylate flux, but IclR still represses transcription. Finally, in E. coli BL21 (DE3, ArcA and IclR are poorly expressed, explaining the similar fluxes observed compared to the ΔarcAΔiclR strain.

  3. Nucleotide sequence, mutational analysis, transcriptional start site, and product analysis of nov, the gene which affects Escherichia coli K-12 resistance to the gyrase inhibitor novobiocin. (United States)

    Ivanisevic, R; Milić, M; Ajdić, D; Rakonjac, J; Savić, D J


    In a previous study, we demonstrated the existence of a gene locus, nov, which affects resistance of Escherichia coli K-12 to the gyrase inhibitor novobiocin and, to a lesser degree, coumermycin (J. Rakonjac, M. Milic, D. Ajdic, D. Santos, R. Ivanisevic, and D. J. Savic, Mol. Microbiol. 6:1547-1553, 1992). In the present study, sequencing of the nov gene locus revealed one open reading frame that encodes a protein of 54,574 Da, a value. found to be in correspondence with the size of the Nov protein identified in an in vitro translation system. We also located the 5' end of the nov transcript 8 bp downstream from a classical sigma70 promoter. Transcription of the gene is in the counterclockwise direction on the E. coli chromosome. Transposon mutagenesis of nov followed by complementation analyses and replacement of chromosomal alleles with mutated nov confirmed our previous assumption that the nov gene exists in two allelic forms and that the Novr gene is an active allele while the Novs gene is an inactive form. After comparing nucleotide sequences flanking the nov gene with existing data, we conclude that the gene order in this region of the E. coli K-12 map is att phi 80-open reading frame of unknown function-kch (potassium channel protein)-nov-opp. Finally, the possible identity of the nov gene with cls, the gene that codes for cardiolipin synthase, is also discussed.

  4. Genome-wide Reconstruction of OxyR and SoxRS Transcriptional Regulatory Networks under Oxidative Stress in Escherichia coli K-12 MG1655

    DEFF Research Database (Denmark)

    Seo, Sang Woo; Kim, Donghyuk; Szubin, Richard


    Three transcription factors (TFs), OxyR, SoxR, and SoxS, play a critical role in transcriptional regulation of the defense system for oxidative stress in bacteria. However, their full genome-wide regulatory potential is unknown. Here, we perform a genome-scale reconstruction of the OxyR, Sox......R, and SoxS regulons in Escherichia coli K-12 MG1655. Integrative data analysis reveals that a total of 68 genes in 51 transcription units (TUs) belong to these regulons. Among them, 48 genes showed more than 2-fold changes in expression level under single-TF-knockout conditions. This reconstruction expands...

  5. Mechanism for regulation of the putrescine utilization pathway by the transcription factor PuuR in Escherichia coli K-12. (United States)

    Nemoto, Naoki; Kurihara, Shin; Kitahara, Yuzuru; Asada, Kei; Kato, Kenji; Suzuki, Hideyuki


    In Escherichia coli, putrescine is metabolized to succinate for use as a carbon and nitrogen source by the putrescine utilization pathway (Puu pathway). One gene in the puu gene cluster encodes a transcription factor, PuuR, which has a helix-turn-helix DNA-binding motif. DNA microarray analysis of an E. coli puuR mutant, in which three amino acid residues in the helix-turn-helix DNA binding motif of PuuR were mutated to alanine to eliminate DNA binding of PuuR, suggested that PuuR is a negative regulator of puu genes. Results of gel shift and DNase I footprint analyses suggested that PuuR binds to the promoter regions of puuA and puuD. The binding of wild-type PuuR to a DNA probe containing PuuR recognition sites was diminished with increasing putrescine concentrations in vitro. These results suggest that PuuR regulates the intracellular putrescine concentration by the transcriptional regulation of genes in the Puu pathway, including puuR itself. The puu gene cluster is found in E. coli and closely related enterobacteria, but this gene cluster is uncommon in other bacterial groups. E. coli and related enterobacteria may have gained the Puu pathway as an adaptation for survival in the mammalian intestine, an environment in which polyamines exist at relatively high concentrations.

  6. Biogenic synthesis and characterization of gold nanoparticles by Escherichia coli K12 and its heterogeneous catalysis in degradation of 4-nitrophenol (United States)

    Srivastava, Sarvesh Kumar; Yamada, Ryosuke; Ogino, Chiaki; Kondo, Akihiko


    Room-temperature extracellular biosynthesis of gold nanoparticles (Au NPs) was achieved using Escherichia coli K12 cells without the addition of growth media, pH adjustments or inclusion of electron donors/stabilizing agents. The resulting nanoparticles were analysed by ultraviolet-visible (UV-vis) spectrophotometry, atomic force microscopy, transmission electron microscopy and X-ray diffraction. Highly dispersed gold nanoplates were achieved in the order of around 50 nm. Further, the underlying mechanism was found to be controlled by certain extracellular membrane-bound proteins, which was confirmed by Fourier transformation-infrared spectroscopy and sodium dodecyl sulfate polyacrylamide gel electrophoresis. We observed that certain membrane-bound peptides are responsible for reduction and subsequent stabilization of Au NPs (confirmed by zeta potential analysis). Upon de-activation of these proteins, no nanoparticle formation was observed. Also, we prepared a novel biocatalyst with Au NPs attached to the membrane-bound fraction of E. coli K12 cells serving as an efficient heterogeneous catalyst in complete reduction of 4-nitrophenol in the presence of NaBH4 which was studied with UV-vis spectroscopy. This is the first report on bacterial membrane-Au NP nanobiocomposite serving as an efficient heterogeneous catalyst in complete reduction of nitroaromatic pollutant in water.

  7. Formation of a lambda (Tn10) tyrR+ specialized transducing bacteriophage from Escherichia coli K-12. (United States)

    Cobbett, C S; Pittard, J


    The transposon Tn10, coding for resistance to tetracycline, was inserted close to the tyrR+ gene at min 28 on the Escherichia coli chromosome. The homology between this transposon and a lambda (Tn10) phage was employed to direct integration of lambda close to tyrR+ with subsequent isolation of a lambda (Tn10) tyrR+ transducing phage. Results of restriction endonuclease analysis of the transducing phage are presented. Images PMID:6254949

  8. O acetylation of the enterobacterial common antigen polysaccharide is catalyzed by the product of the yiaH gene of Escherichia coli K-12. (United States)

    Kajimura, Junko; Rahman, Arifur; Hsu, James; Evans, Matthew R; Gardner, Kevin H; Rick, Paul D


    The carbohydrate component of the enterobacterial common antigen (ECA) of Escherichia coli K-12 occurs primarily as a water-soluble cyclic polysaccharide located in the periplasm (ECA(CYC)) and as a phosphoglyceride-linked linear polysaccharide located on the cell surface (ECA(PG)). The polysaccharides of both forms are comprised of the amino sugars N-acetyl-D-glucosamine (GlcNAc), N-acetyl-D-mannosaminuronic acid (ManNAcA), and 4-acetamido-4,6-dideoxy-D-galactose (Fuc4NAc). These amino sugars are linked to one another to form trisaccharide repeat units with the structure -->3-alpha-D-Fuc4NAc-(1-->4)-beta-D-ManNAcA-(1-->4)-alpha-D-GlcNAc-(1-->. The hydroxyl group in the 6 position of the GlcNAc residues of both ECA(CYC) and ECA(PG) are nonstoichiometrically esterified with acetyl groups. Random transposon insertion mutagenesis of E. coli K-12 resulted in the generation of a mutant defective in the incorporation of O-acetyl groups into both ECA(CYC) and ECA(PG). This defect was found to be due to an insertion of the transposon into the yiaH locus, a putative gene of unknown function located at 80.26 min on the E. coli chromosomal map. Bioinformatic analyses of the predicted yiaH gene product indicate that it is an integral inner membrane protein that is a member of an acyltransferase family of enzymes found in a wide variety of organisms. The results of biochemical and genetic experiments presented here strongly support the conclusion that yiaH encodes the O-acetyltransferase responsible for the incorporation of O-acetyl groups into both ECA(CYC) and ECA(PG). Accordingly, we propose that this gene be designated wecH.

  9. Interaction of lead nitrate and cadmium chloride with Escherichia coli K-12 and Salmonella typhimurium global regulatory mutants. (United States)

    LaRossa, R A; Smulski, D R; Van Dyk, T K


    To investigate the interactions of heavy metals with cells, a minimal medium for the growth of enteric bacteria using glycerol-2-phosphate as the sole phosphorus source was developed that avoided precipitation of Pb2+ with inorganic phosphate. Using this medium, spontaneous mutants of Escherichia coli resistant to addition of Pb(NO3)2 were isolated. Thirty-five independent mutants all conferred a low level of resistance. Disk diffusion assays on solid medium were used to survey the response of E. coli and Salmonella typhimurium mutants altered in global regulatory networks to Pb(NO3)2 and CdCl2. Strains bearing mutations in oxyR and rpoH were the most hypersensitive to these compounds. Based upon the response of strains completely devoid of isozymes needed to inactivate reactive oxygen species, this hypersensitivity to lead and cadmium is attributable to alteration in superoxide dismutase rather than catalase levels. Similar analysis of chaperone-defective mutants suggests that these metals damage proteins in vivo.

  10. Directional RNA-seq reveals highly complex condition-dependent transcriptomes in E. coli K12 through accurate full-length transcripts assembling (United States)


    Background Although prokaryotic gene transcription has been studied over decades, many aspects of the process remain poorly understood. Particularly, recent studies have revealed that transcriptomes in many prokaryotes are far more complex than previously thought. Genes in an operon are often alternatively and dynamically transcribed under different conditions, and a large portion of genes and intergenic regions have antisense RNA (asRNA) and non-coding RNA (ncRNA) transcripts, respectively. Ironically, similar studies have not been conducted in the model bacterium E coli K12, thus it is unknown whether or not the bacterium possesses similar complex transcriptomes. Furthermore, although RNA-seq becomes the major method for analyzing the complexity of prokaryotic transcriptome, it is still a challenging task to accurately assemble full length transcripts using short RNA-seq reads. Results To fill these gaps, we have profiled the transcriptomes of E. coli K12 under different culture conditions and growth phases using a highly specific directional RNA-seq technique that can capture various types of transcripts in the bacterial cells, combined with a highly accurate and robust algorithm and tool TruHMM ( for assembling full length transcripts. We found that 46.9 ~ 63.4% of expressed operons were utilized in their putative alternative forms, 72.23 ~ 89.54% genes had putative asRNA transcripts and 51.37 ~ 72.74% intergenic regions had putative ncRNA transcripts under different culture conditions and growth phases. Conclusions As has been demonstrated in many other prokaryotes, E. coli K12 also has a highly complex and dynamic transcriptomes under different culture conditions and growth phases. Such complex and dynamic transcriptomes might play important roles in the physiology of the bacterium. TruHMM is a highly accurate and robust algorithm for assembling full-length transcripts in prokaryotes using directional RNA

  11. A novel role for RecA under non-stress: promotion of swarming motility in Escherichia coli K-12

    Directory of Open Access Journals (Sweden)

    Blázquez Jesús


    Full Text Available Abstract Background Bacterial motility is a crucial factor in the colonization of natural environments. Escherichia coli has two flagella-driven motility types: swimming and swarming. Swimming motility consists of individual cell movement in liquid medium or soft semisolid agar, whereas swarming is a coordinated cellular behaviour leading to a collective movement on semisolid surfaces. It is known that swimming motility can be influenced by several types of environmental stress. In nature, environmentally induced DNA damage (e.g. UV irradiation is one of the most common types of stress. One of the key proteins involved in the response to DNA damage is RecA, a multifunctional protein required for maintaining genome integrity and the generation of genetic variation. Results The ability of E. coli cells to develop swarming migration on semisolid surfaces was suppressed in the absence of RecA. However, swimming motility was not affected. The swarming defect of a ΔrecA strain was fully complemented by a plasmid-borne recA gene. Although the ΔrecA cells grown on semisolidsurfaces exhibited flagellar production, they also presented impaired individual movement as well as a fully inactive collective swarming migration. Both the comparative analysis of gene expression profiles in wild-type and ΔrecA cells grown on a semisolid surface and the motility of lexA1 [Ind-] mutant cells demonstrated that the RecA effect on swarming does not require induction of the SOS response. By using a RecA-GFP fusion protein we were able to segregate the effect of RecA on swarming from its other functions. This protein fusion failed to regulate the induction of the SOS response, the recombinational DNA repair of UV-treated cells and the genetic recombination, however, it was efficient in rescuing the swarming motility defect of the ΔrecA mutant. The RecA-GFP protein retains a residual ssDNA-dependent ATPase activity but does not perform DNA strand exchange. Conclusion

  12. [Intra- and intermolecular recombination of test plasmids in K12 Escherichia coli cells carrying an RTF derivative of the R1drd-19 plasmid]. (United States)

    Terent'ev, M A; Chenin, L S


    The RTF derivative of the plasmid R1drd-19 was found to stimulate recombination of the tester plasmids in a recB mutant of Escherichia coli K12. The frequency of intramolecular recombination is increased 3.5 and 20-fold, as compared to the one in rec+ and rec- strains, respectively. The frequency of interplasmid recombination is enhanced 4 and 9-fold, respectively. Considerable heterogeneity of the recombination products of the tester plasmid intramolecular recombination in recB-/RTFR1-19 strain has been revealed. It is hypothesized that a "recombinase" encoded by Rldrd-19 plasmid determines a new minor pathway in recB- (Rec P) which differs in activity and, perhaps substrate specificity from the main Rec BCD pathway.

  13. RecA4142 Causes SOS Constitutive Expression by Loading onto Reversed Replication Forks in Escherichia coli K-12 (United States)

    Long, Jarukit Edward; Massoni, Shawn C.; Sandler, Steven J.


    Escherichia coli initiates the SOS response when single-stranded DNA (ssDNA) produced by DNA damage is bound by RecA and forms a RecA-DNA filament. recA SOS constitutive [recA(Con)] mutants induce the SOS response in the absence of DNA damage. It has been proposed that recA(Con) mutants bind to ssDNA at replication forks, although the specific mechanism is unknown. Previously, it had been shown that recA4142(F217Y), a novel recA(Con) mutant, was dependent on RecBCD for its high SOS constitutive [SOS(Con)] expression. This was presumably because RecA4142 was loaded at a double-strand end (DSE) of DNA. Herein, it is shown that recA4142 SOS(Con) expression is additionally dependent on ruvAB (replication fork reversal [RFR] activity only) and recJ (5′→3′ exonuclease), xonA (3′→5′ exonuclease) and partially dependent on recQ (helicase). Lastly, sbcCD mutations (Mre11/Rad50 homolog) in recA4142 strains caused full SOS(Con) expression in an ruvAB-, recBCD-, recJ-, and xonA-independent manner. It is hypothesized that RuvAB catalyzes RFR, RecJ and XonA blunt the DSE (created by the RFR), and then RecBCD loads RecA4142 onto this end to produce SOS(Con) expression. In sbcCD mutants, RecA4142 can bind other DNA substrates by itself that are normally degraded by the SbcCD nuclease. PMID:20304994

  14. RfaH suppresses small RNA MicA inhibition of fimB expression in Escherichia coli K-12. (United States)

    Moores, Alexandra; Chipper-Keating, Saranna; Sun, Lei; McVicker, Gareth; Wales, Lynn; Gashi, Krishna; Blomfield, Ian C


    The phase variation (reversible on-off switching) of the type 1 fimbrial adhesin of Escherichia coli involves a DNA inversion catalyzed by FimB (switching in either direction) or FimE (on-to-off switching). Here, we demonstrate that RfaH activates expression of a FimB-LacZ protein fusion while having a modest inhibitory effect on a comparable fimB-lacZ operon construct and on a FimE-LacZ protein fusion, indicating that RfaH selectively controls fimB expression at the posttranscriptional level. Further work demonstrates that loss of RfaH enables small RNA (sRNA) MicA inhibition of fimB expression even in the absence of exogenous inducing stress. This effect is explained by induction of σ(E), and hence MicA, in the absence of RfaH. Additional work confirms that the procaine-dependent induction of micA requires OmpR, as reported previously (A. Coornaert et al., Mol. Microbiol. 76:467-479, 2010, doi:10.1111/j.1365-2958.2010.07115.x), but also demonstrates that RfaH inhibition of fimB transcription is enhanced by procaine independently of OmpR. While the effect of procaine on fimB transcription is shown to be independent of RcsB, it was found to require SlyA, another known regulator of fimB transcription. These results demonstrate a complex role for RfaH as a regulator of fimB expression.

  15. SlyA Protein Activates fimB Gene Expression and Type 1 Fimbriation in Escherichia coli K-12* (United States)

    McVicker, Gareth; Sun, Lei; Sohanpal, Baljinder K.; Gashi, Krishna; Williamson, Richard A.; Plumbridge, Jacqueline; Blomfield, Ian C.


    We have demonstrated that SlyA activates fimB expression and hence type 1 fimbriation, a virulence factor in Escherichia coli. SlyA is shown to bind to two operator sites (OSA1 and OSA2), situated between 194 and 167 base pairs upstream of the fimB transcriptional start site. fimB expression is derepressed in an hns mutant and diminished by a slyA mutation in the presence of H-NS only. H-NS binds to multiple sites in the promoter region, including two sites (H-NS2 and H-NS3) that overlap OSA1 and OSA2, respectively. Mutations that disrupt either OSA1 or OSA2 eliminate or reduce the activating effect of SlyA but have different effects on the level of expression. We interpret these results as reflecting the relative competition between SlyA and H-NS binding. Moreover we show that SlyA is capable of displacing H-NS from its binding sites in vitro. We suggest SlyA binding prevents H-NS binding to H-NS2 and H-NS3 and the subsequent oligomerization of H-NS necessary for full inhibition of fimB expression. In addition, we show that SlyA activates fimB expression independently of two other known regulators of fimB expression, NanR and NagC. It is demonstrated that the rarely used UUG initiation codon limits slyA expression and that low SlyA levels limit fimB expression. Furthermore, Western blot analysis shows that cells grown in rich-defined medium contain ∼1000 SlyA dimers per cell whereas those grown in minimal medium contain >20% more SlyA. This study extends our understanding of the role that SlyA plays in the host-bacterial relationship. PMID:21768111

  16. SlyA protein activates fimB gene expression and type 1 fimbriation in Escherichia coli K-12. (United States)

    McVicker, Gareth; Sun, Lei; Sohanpal, Baljinder K; Gashi, Krishna; Williamson, Richard A; Plumbridge, Jacqueline; Blomfield, Ian C


    We have demonstrated that SlyA activates fimB expression and hence type 1 fimbriation, a virulence factor in Escherichia coli. SlyA is shown to bind to two operator sites (O(SA1) and O(SA2)), situated between 194 and 167 base pairs upstream of the fimB transcriptional start site. fimB expression is derepressed in an hns mutant and diminished by a slyA mutation in the presence of H-NS only. H-NS binds to multiple sites in the promoter region, including two sites (H-NS2 and H-NS3) that overlap O(SA1) and O(SA2), respectively. Mutations that disrupt either O(SA1) or O(SA2) eliminate or reduce the activating effect of SlyA but have different effects on the level of expression. We interpret these results as reflecting the relative competition between SlyA and H-NS binding. Moreover we show that SlyA is capable of displacing H-NS from its binding sites in vitro. We suggest SlyA binding prevents H-NS binding to H-NS2 and H-NS3 and the subsequent oligomerization of H-NS necessary for full inhibition of fimB expression. In addition, we show that SlyA activates fimB expression independently of two other known regulators of fimB expression, NanR and NagC. It is demonstrated that the rarely used UUG initiation codon limits slyA expression and that low SlyA levels limit fimB expression. Furthermore, Western blot analysis shows that cells grown in rich-defined medium contain ~1000 SlyA dimers per cell whereas those grown in minimal medium contain >20% more SlyA. This study extends our understanding of the role that SlyA plays in the host-bacterial relationship.

  17. Loss of expression of cspC, a cold shock family gene, confers a gain of fitness in Escherichia coli K-12 strains. (United States)

    Rath, Devashish; Jawali, Narendra


    The CspA family of cold shock genes in Escherichia coli K-12 includes nine paralogs, cspA to cspI. Some of them have been implicated in cold stress adaptation. Screening for mutations among common laboratory E. coli strains showed a high degree of genetic diversity in cspC but not in cspA and cspE. This diversity in cspC was due to a wide spectrum of variations including insertions of IS elements, deletion, and point mutation. Northern analysis of these mutants showed loss of cspC expression in all but one case. Further analysis of the loss-of-function cspC mutants showed that they have a fitness advantage in broth culture after 24 h over their isogenic wild-type derivatives. Conversely, introduction of mutated cspC alleles conferred a competitive fitness advantage to AB1157, a commonly used laboratory strain. This provides the evidence that loss of cspC expression is both necessary and sufficient to confer a gain of fitness as seen in broth culture over 24 h. Together, these results ascribe a novel role in cellular growth at 37 degrees C for CspC, a member of the cold shock domain-containing protein family.

  18. Escherichia coli K-12 survives anaerobic exposure at pH 2 without RpoS, Gad, or hydrogenases, but shows sensitivity to autoclaved broth products.

    Directory of Open Access Journals (Sweden)

    Daniel P Riggins

    Full Text Available Escherichia coli and other enteric bacteria survive exposure to extreme acid (pH 2 or lower in gastric fluid. Aerated cultures survive via regulons expressing glutamate decarboxylase (Gad, activated by RpoS, cyclopropane fatty acid synthase (Cfa and others. But extreme-acid survival is rarely tested under low oxygen, a condition found in the stomach and the intestinal tract. We observed survival of E. coli K-12 W3110 at pH 1.2-pH 2.0, conducting all manipulations (overnight culture at pH 5.5, extreme-acid exposure, dilution and plating in a glove box excluding oxygen (10% H2, 5% CO2, balance N2. With dissolved O2 concentrations maintained below 6 µM, survival at pH 2 required Cfa but did not require GadC, RpoS, or hydrogenases. Extreme-acid survival in broth (containing tryptone and yeast extract was diminished in media that had been autoclaved compared to media that had been filtered. The effect of autoclaved media on extreme-acid survival was most pronounced when oxygen was excluded. Exposure to H2O2 during extreme-acid treatment increased the death rate slightly for W3110 and to a greater extent for the rpoS deletion strain. Survival at pH 2 was increased in strains lacking the anaerobic regulator fnr. During anaerobic growth at pH 5.5, strains deleted for fnr showed enhanced transcription of acid-survival genes gadB, cfa, and hdeA, as well as catalase (katE. We show that E. coli cultured under oxygen exclusion (<6 µM O2 requires mechanisms different from those of aerated cultures. Extreme acid survival is more sensitive to autoclave products under oxygen exclusion.

  19. [The influence of Bordetella pertussis bvgAS operon on formation and resolution of plasmid-chromosome cointegrates in Escherichia coli K12 mutants with damages in common components of the phosphoenolpyruvate:sugar phosphotransferase system]. (United States)

    Umiarov, A M; Siniashina, L N; Amelina, I P; Datsenko, K A; Bol'shakova, T N; Dobrynina, O Iu; Karataev, G I


    The plasmids containing the genetically marked variants of Bordetela pertussi transposon TnBP were synthesized on the base of the plasmid with thermosensitive replication. The integration frequency of these plasmids into the E.coli K12 chromosome at non-permissive temperature (42 degrees C) was determined. It was found that the frequency of forming of RSBP-induced plasmid-chromosome cointegrated in bacteria E.coli K12 deficient in HPr or Enzyme I of the phosphoenolpyruvate:sugar phosphotransferase system was decreased. The bvgAS operon from B.pertussis in trans-position restores the ability of mutant E.coli K12 to form and resolve.

  20. Rpn (YhgA-Like) Proteins of Escherichia coli K-12 and Their Contribution to RecA-Independent Horizontal Transfer. (United States)

    Kingston, Anthony W; Ponkratz, Christine; Raleigh, Elisabeth A


    Bacteria use a variety of DNA-mobilizing enzymes to facilitate environmental niche adaptation via horizontal gene transfer. This has led to real-world problems, like the spread of antibiotic resistance, yet many mobilization proteins remain undefined. In the study described here, we investigated the uncharacterized family of YhgA-like transposase_31 (Pfam PF04754) proteins. Our primary focus was the genetic and biochemical properties of the five Escherichia coli K-12 members of this family, which we designate RpnA to RpnE, where Rpn represents r ecombination- p romoting n uclease. We employed a conjugal system developed by our lab that demanded RecA-independent recombination following transfer of chromosomal DNA. Overexpression of RpnA (YhgA), RpnB (YfcI), RpnC (YadD), and RpnD (YjiP) increased RecA-independent recombination, reduced cell viability, and induced the expression of reporter of DNA damage. For the exemplar of the family, RpnA, mutational changes in proposed catalytic residues reduced or abolished all three phenotypes in concert. In vitro , RpnA displayed magnesium-dependent, calcium-stimulated DNA endonuclease activity with little, if any, sequence specificity and a preference for double-strand cleavage. We propose that Rpn/YhgA-like family nucleases can participate in gene acquisition processes. IMPORTANCE Bacteria adapt to new environments by obtaining new genes from other bacteria. Here, we characterize a set of genes that can promote the acquisition process by a novel mechanism. Genome comparisons had suggested the horizontal spread of the genes for the YhgA-like family of proteins through bacteria. Although annotated as transposase_31, no member of the family has previously been characterized experimentally. We show that four Escherichia coli K-12 paralogs contribute to a novel RecA-independent recombination mechanism in vivo For RpnA, we demonstrate in vitro action as a magnesium-dependent, calcium-stimulated nonspecific DNA endonuclease. The

  1. First report on rapid screening of nanomaterial-based antimicrobial agents against β-lactamase resistance using pGLO plasmid transformed Escherichia coli HB 101 K-12 (United States)

    Raj, M. Alpha; Muralidhar, Y.; Sravanthi, M.; Prasad, T. N. V. K. V.; Nissipriya, M.; Reddy, P. Sirisha; Neelima, T. Shoba; Reddy, G. Dilip; Adilaxmamma, K.; Kumar, P. Anand; Krishna, T. Giridhara


    Combating antibiotic resistance requires discovery of novel antimicrobials effective against resistant bacteria. Herein, we present for the first time, pGLO plasmid transformed Escherichia coli HB 101 K 12 as novel model for screening of nanomaterial-based antimicrobial agents against β-lactamase resistance. E. coli HB 101 was transformed by pGLO plasmid in the presence of calcium chloride (50 mM; pH 6.1) aided by heat shock (0-42-0 °C). The transformed bacteria were grown on Luria-Bertani agar containing ampicillin (amp) and arabinose (ara). The transformed culture was able to grow in the presence of ampicillin and also exhibited fluorescence under UV light. Both untransformed and transformed bacteria were used for screening citrate-mediated nanosilver (CNS), aloin-mediated nanosilver (ANS), 11-α-keto-boswellic acid (AKBA)-mediated nanosilver (BNS); nanozinc oxide, nanomanganese oxide (NMO) and phytochemicals such as aloin and AKBA. Minimum inhibitory concentrations (MIC) were obtained by microplate method using ρ-iodo nitro tetrazolium indicator. All the compounds were effective against transformed bacteria except NMO and AKBA. Transformed bacteria exhibited reverse cross resistance against aloin. ANS showed the highest antibacterial activity with a MIC of 0.32 ppm followed by BNS (10.32 ppm), CNS (20.64 ppm) and NZO (34.83 ppm). Thus, pGLO plasmid can be used to induce resistance against β-lactam antibiotics and the model can be used for rapid screening of new antibacterial agents effective against resistant bacteria.

  2. Genome-wide Reconstruction of OxyR and SoxRS Transcriptional Regulatory Networks under Oxidative Stress in Escherichia coli K-12 MG1655

    Directory of Open Access Journals (Sweden)

    Sang Woo Seo


    Full Text Available Three transcription factors (TFs, OxyR, SoxR, and SoxS, play a critical role in transcriptional regulation of the defense system for oxidative stress in bacteria. However, their full genome-wide regulatory potential is unknown. Here, we perform a genome-scale reconstruction of the OxyR, SoxR, and SoxS regulons in Escherichia coli K-12 MG1655. Integrative data analysis reveals that a total of 68 genes in 51 transcription units (TUs belong to these regulons. Among them, 48 genes showed more than 2-fold changes in expression level under single-TF-knockout conditions. This reconstruction expands the genome-wide roles of these factors to include direct activation of genes related to amino acid biosynthesis (methionine and aromatic amino acids, cell wall synthesis (lipid A biosynthesis and peptidoglycan growth, and divalent metal ion transport (Mn2+, Zn2+, and Mg2+. Investigating the co-regulation of these genes with other stress-response TFs reveals that they are independently regulated by stress-specific TFs.

  3. Comparative study of time-dependent effects of 4 and 8 Hz mechanical vibration at infrasound frequency on E. coli K-12 cells proliferation. (United States)

    Martirosyan, Varsik; Ayrapetyan, Sinerik


    The aim of the present work is to study the time-dependent effects of mechanical vibration (MV) at infrasound (IS) frequency at 4 and 8 Hz on E. coli K-12 growth by investigating the cell proliferation, using radioactive [(3)H]-thymidine assay. In our previous work it was suggested that the aqua medium can serve as a target through which the biological effect of MV on microbes could be realized. At the same time it was shown that microbes have mechanosensors on the surface of the cells and can sense small changes of the external environment. The obtained results were shown that the time-dependent effects of MV at 4 and 8 Hz frequency could either stimulate or inhibit the growth of microbes depending from exposure time. It more particularly, the invention relates to a method for controlling biological functions through the application of mechanical vibration, thus making it possible to artificially control the functions of bacterial cells, which will allow us to develop method that can be used in agriculture, industry, medicine, biotechnology to control microbial growth.

  4. The study of the effects of mechanical vibration at infrasound frequency on [(3)H]-thymidine incorporation into DNA of E. coli K-12. (United States)

    Martirosyan, Varsik; Baghdasaryan, Naira; Ayrapetyan, Sinerik


    The aim of the present work was to investigate the frequency-dependent effects of mechanical vibration at infrasound frequency (MV at IS frequency or MV) on E. coli K-12 growth by investigating the cell proliferation, using radioactive [(3)H]-thymidine assay. The frequency-dependent effects of MV were shown that it could either stimulate or inhibit the growth of microbes. However, the mechanism through which the MV effects affect the bacterial cells is not clear yet. It was suggested that the aqua medium can serve as a target through which the biological effect of MV on microbes could be realized. To check this hypothesis the frequency-dependent effect (2, 4, 6, 8, 10 Hz) of MV on the bacterial growth in cases of exposure the preliminary treated microbes-free medium and microbes containing medium were studied. It has been shown that MV at 4, 8, and 10 Hz frequency has inhibition effects, while at 2 and 6 Hz has stimulation effects on cell proliferation.

  5. Oxygen limitation modulates pH regulation of catabolism and hydrogenases, multidrug transporters, and envelope composition in Escherichia coli K-12

    Directory of Open Access Journals (Sweden)

    Radmacher Michael D


    Full Text Available Abstract Background In Escherichia coli, pH regulates genes for amino-acid and sugar catabolism, electron transport, oxidative stress, periplasmic and envelope proteins. Many pH-dependent genes are co-regulated by anaerobiosis, but the overall intersection of pH stress and oxygen limitation has not been investigated. Results The pH dependence of gene expression was analyzed in oxygen-limited cultures of E. coli K-12 strain W3110. E. coli K-12 strain W3110 was cultured in closed tubes containing LBK broth buffered at pH 5.7, pH 7.0, and pH 8.5. Affymetrix array hybridization revealed pH-dependent expression of 1,384 genes and 610 intergenic regions. A core group of 251 genes showed pH responses similar to those in a previous study of cultures grown with aeration. The highly acid-induced gene yagU was shown to be required for extreme-acid resistance (survival at pH 2. Acid also up-regulated fimbriae (fimAC, periplasmic chaperones (hdeAB, cyclopropane fatty acid synthase (cfa, and the "constitutive" Na+/H+ antiporter (nhaB. Base up-regulated core genes for maltodextrin transport (lamB, mal, ATP synthase (atp, and DNA repair (recA, mutL. Other genes showed opposite pH responses with or without aeration, for example ETS components (cyo,nuo, sdh and hydrogenases (hya, hyb, hyc, hyf, hyp. A hypF strain lacking all hydrogenase activity showed loss of extreme-acid resistance. Under oxygen limitation only, acid down-regulated ribosome synthesis (rpl,rpm, rps. Acid up-regulated the catabolism of sugar derivatives whose fermentation minimized acid production (gnd, gnt, srl, and also a cluster of 13 genes in the gadA region. Acid up-regulated drug transporters (mdtEF, mdtL, but down-regulated penicillin-binding proteins (dacACD, mreBC. Intergenic regions containing regulatory sRNAs were up-regulated by acid (ryeA, csrB, gadY, rybC. Conclusion pH regulates a core set of genes independently of oxygen, including yagU, fimbriae, periplasmic chaperones, and nha

  6. Structural insights into the substrate specificity and function of Escherichia coli K12 YgjK, a glucosidase belonging to the glycoside hydrolase family 63. (United States)

    Kurakata, Yuma; Uechi, Akiko; Yoshida, Hiromi; Kamitori, Shigehiro; Sakano, Yoshiyuki; Nishikawa, Atsushi; Tonozuka, Takashi


    Proteins belonging to the glycoside hydrolase family 63 (GH63) are found in bacteria, archaea, and eukaryotes. Eukaryotic GH63 proteins are processing *-glucosidase I enzymes that hydrolyze an oligosaccharide precursor of eukaryotic N-linked glycoproteins. In contrast, the functions of the bacterial and archaeal GH63 proteins are unclear. Here we determined the crystal structure of a bacterial GH63 enzyme, Escherichia coli K12 YgjK, at 1.78 A resolution and investigated some properties of the enzyme. YgjK consists of the N-domain and the A-domain, joined by a linker region. The N-domain is composed of 18 antiparallel beta-strands and is classified as a super-beta-sandwich. The A-domain contains 16 *-helices, 12 of which form an (*/*)(6)-barrel; the remaining 4 *-helices are found in an extra structural unit that we designated as the A'-region. YgjK, a member of the glycoside hydrolase clan GH-G, shares structural similarity with glucoamylase (GH15) and chitobiose phosphorylase (GH94) [corrected] both of which belong to clan GH-L or GH-L-like [corrected] In crystal structures of YgjK in complex with glucose, mannose, and galactose, all of the glucose, mannose, and galactose units were located in the catalytic cleft. YgjK showed the highest activity for the *-1,3-glucosidic linkage of nigerose, but also hydrolyzed trehalose, kojibiose, and maltooligosaccharides from maltose to maltoheptaose, although the activities were low. These findings suggest that YgjK is a glucosidase with relaxed specificity for sugars.

  7. Simultaneous substitution of Gly96 to Ala and Ala183 to Thr in 5-enolpyruvylshikimate-3-phosphate synthase gene of E. coli (k12) and transformation of rapeseed (Brassica napus L.) in order to make tolerance to glyphosate. (United States)

    Kahrizi, Danial; Salmanian, Ali Hatef; Afshari, Afsoon; Moieni, Ahmad; Mousavi, Amir


    Glyphosate is a non-selective broad-spectrum herbicide that inhibits 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). This is a key enzyme in the aromatic amino acid biosynthesis pathway of microorganisms and plants. The manipulation of bacterial EPSPS gene in order to reduce its affinity for glyphosate, followed by its transfer to plants is one of the most effective approaches for the production of glyphosate-tolerant plants. In this study, we chose to focus on amino acid residues glycine96 and alanine183 of the E. coli (k12) EPSPS enzyme. These two amino acids are important residues for glyphosate binding. We used site directed mutagenesis (SDM) to induce point mutations in the E. coli EPSPS gene, in order to convert glycine96 to alanine (Gly96Ala) and alanine183 to threonine (Ala183Thr). After confirming the mutation by sequencing, the altered EPSPS gene was transferred to rapeseed (Brassica napus L.) via Agrobacterium-mediated transformation. The transformed explants were screened in shoot induction medium containing 25 mg L-1 kanamycin. Glyphosate tolerance was assayed in putative transgenic plants. Statistical analysis of data showed that there was a significant difference between the transgenic and control plants. It was observed that transgenic plants were resistant to glyphosate at a concentration of 10 mM whereas the non-transformed control plants were unable to survive 1 mM glyphosate. The presence and copy numbers of the transgene were confirmed with PCR and Southern blotting analysis, respectively.

  8. Structural Basis for Substrate Specificity in Phosphate Binding (beta/alpha)8-Barrels: D-Allulose 6-Phosphate 3-Epimerase from Escherichia coli K-12

    Energy Technology Data Exchange (ETDEWEB)

    Chan,K.; Fedorov, A.; Almo, S.; Gerlt, J.


    Enzymes that share the ({beta}/{alpha})8-barrel fold catalyze a diverse range of reactions. Many utilize phosphorylated substrates and share a conserved C-terminal ({beta}/a)2-quarter barrel subdomain that provides a binding motif for the dianionic phosphate group. We recently reported functional and structural studies of d-ribulose 5-phosphate 3-epimerase (RPE) from Streptococcus pyogenes that catalyzes the equilibration of the pentulose 5-phosphates d-ribulose 5-phosphate and d-xylulose 5-phosphate in the pentose phosphate pathway [J. Akana, A. A. Fedorov, E. Fedorov, W. R. P. Novack, P. C. Babbitt, S. C. Almo, and J. A. Gerlt (2006) Biochemistry 45, 2493-2503]. We now report functional and structural studies of d-allulose 6-phosphate 3-epimerase (ALSE) from Escherichia coli K-12 that catalyzes the equilibration of the hexulose 6-phosphates d-allulose 6-phosphate and d-fructose 6-phosphate in a catabolic pathway for d-allose. ALSE and RPE prefer their physiological substrates but are promiscuous for each other's substrate. The active sites (RPE complexed with d-xylitol 5-phosphate and ALSE complexed with d-glucitol 6-phosphate) are superimposable (as expected from their 39% sequence identity), with the exception of the phosphate binding motif. The loop following the eighth {beta}-strand in ALSE is one residue longer than the homologous loop in RPE, so the binding site for the hexulose 6-phosphate substrate/product in ALSE is elongated relative to that for the pentulose 5-phosphate substrate/product in RPE. We constructed three single-residue deletion mutants of the loop in ALSE, ?T196, ?S197 and ?G198, to investigate the structural bases for the differing substrate specificities; for each, the promiscuity is altered so that d-ribulose 5-phosphate is the preferred substrate. The changes in kcat/Km are dominated by changes in kcat, suggesting that substrate discrimination results from differential transition state stabilization. In both ALSE and RPE, the

  9. An Escherichia coli K-12 tktA tktB mutant deficient in transketolase activity requires pyridoxine (vitamin B6) as well as the aromatic amino acids and vitamins for growth. (United States)

    Zhao, G; Winkler, M E


    We show that a tktA tktB double mutant, which is devoid of the two known transketolase isoenzymes of Escherichia coli K-12, requires pyridoxine (vitamin B6) as well as the aromatic amino acids and vitamins for growth. This pyridoxine requirement can also be satisfied by 4-hydroxy-L-threonine or glycolaldehyde. These results provide direct evidence that D-erythrose-4-phosphate is a precursor of the pyridine ring of pyridoxine. In addition, they show that the two major E. coli transketolase isoenzymes are not required for the biosynthesis of D-1-deoxyxylulose, which is thought to be another precursor of pyridoxine. PMID:7928977

  10. An Escherichia coli K-12 tktA tktB mutant deficient in transketolase activity requires pyridoxine (vitamin B6) as well as the aromatic amino acids and vitamins for growth.


    Zhao, G; Winkler, M E


    We show that a tktA tktB double mutant, which is devoid of the two known transketolase isoenzymes of Escherichia coli K-12, requires pyridoxine (vitamin B6) as well as the aromatic amino acids and vitamins for growth. This pyridoxine requirement can also be satisfied by 4-hydroxy-L-threonine or glycolaldehyde. These results provide direct evidence that D-erythrose-4-phosphate is a precursor of the pyridine ring of pyridoxine. In addition, they show that the two major E. coli transketolase iso...

  11. A putrescine-inducible pathway comprising PuuE-YneI in which gamma-aminobutyrate is degraded into succinate in Escherichia coli K-12. (United States)

    Kurihara, Shin; Kato, Kenji; Asada, Kei; Kumagai, Hidehiko; Suzuki, Hideyuki


    Gamma-aminobutyrate (GABA) is metabolized to succinic semialdehyde by GABA aminotransferase (GABA-AT), and the succinic semialdehyde is subsequently oxidized to succinate by succinic semialdehyde dehydrogenase (SSADH). In Escherichia coli, there are duplicate GABA-ATs (GabT and PuuE) and duplicate SSADHs (GabD and YneI). While GabT and GabD have been well studied previously, the characterization and expression analysis of PuuE and YneI are yet to be investigated. By analyzing the amino acid profiles in cells of DeltapuuE and/or DeltagabT mutants, this study demonstrated that PuuE plays an important role in GABA metabolism in E. coli cells. The similarity of the amino acid sequences of PuuE and GabT is 67.4%, and it was biochemically demonstrated that the catalytic center of GabT is conserved as an amino acid residue important for the enzymatic activity in PuuE as Lys-247. However, the regulation of expression of PuuE is significantly different from that of GabT. PuuE is induced by the addition of putrescine to the medium and is repressed by succinate and low aeration conditions; in contrast, GabT is almost constitutive. Similarly, YneI is induced by putrescine, while GabD is not. For E. coli, PuuE is important for utilization of putrescine as a sole nitrogen source and both PuuE and YneI are important for utilization of putrescine as a sole carbon source. The results demonstrate that the PuuE-YneI pathway was a putrescine-inducible GABA degradation pathway for utilizing putrescine as a nutrient source.

  12. A Putrescine-Inducible Pathway Comprising PuuE-YneI in Which γ-Aminobutyrate Is Degraded into Succinate in Escherichia coli K-12 (United States)

    Kurihara, Shin; Kato, Kenji; Asada, Kei; Kumagai, Hidehiko; Suzuki, Hideyuki


    γ-Aminobutyrate (GABA) is metabolized to succinic semialdehyde by GABA aminotransferase (GABA-AT), and the succinic semialdehyde is subsequently oxidized to succinate by succinic semialdehyde dehydrogenase (SSADH). In Escherichia coli, there are duplicate GABA-ATs (GabT and PuuE) and duplicate SSADHs (GabD and YneI). While GabT and GabD have been well studied previously, the characterization and expression analysis of PuuE and YneI are yet to be investigated. By analyzing the amino acid profiles in cells of ΔpuuE and/or ΔgabT mutants, this study demonstrated that PuuE plays an important role in GABA metabolism in E. coli cells. The similarity of the amino acid sequences of PuuE and GabT is 67.4%, and it was biochemically demonstrated that the catalytic center of GabT is conserved as an amino acid residue important for the enzymatic activity in PuuE as Lys-247. However, the regulation of expression of PuuE is significantly different from that of GabT. PuuE is induced by the addition of putrescine to the medium and is repressed by succinate and low aeration conditions; in contrast, GabT is almost constitutive. Similarly, YneI is induced by putrescine, while GabD is not. For E. coli, PuuE is important for utilization of putrescine as a sole nitrogen source and both PuuE and YneI are important for utilization of putrescine as a sole carbon source. The results demonstrate that the PuuE-YneI pathway was a putrescine-inducible GABA degradation pathway for utilizing putrescine as a nutrient source. PMID:20639325

  13. Impact of metal ion homeostasis of genetically modified Escherichia coli Nissle 1917 and K12 (W3110) strains on colonization properties in the murine intestinal tract


    Kupz, Andreas; Fischer, André; Nies, Dietrich H.; Grass, Gregor; Göbel, Ulf B.; Bereswill, Stefan; Heimesaat, Markus M.


    Metal ions are integral parts of pro- as well as eukaryotic cell homeostasis. Escherichia coli proved a valuable in vitro model organism to elucidate essential mechanisms involved in uptake, storage, and export of metal ions. Given that E. coli Nissle 1917 is able to overcome murine colonization resistance, we generated several E. coli Nissle 1917 mutants with defects in zinc, iron, copper, nickel, manganese homeostasis and performed a comprehensive survey of the impact of m...

  14. Efficacy of a novel sanitizer composed of lactic acid and peroxyacetic acid against single strains of nonpathogenic Escherichia coli K-12, Listeria innocua, and Lactobacillus plantarum in aqueous solution and on surfaces of romaine lettuce and spinach. (United States)

    Grace Ho, Kai-Lai; Luzuriaga, Diego A; Rodde, Kenneth M; Tang, Shannon; Phan, Cuong


    A novel sanitizer composed of lactic acid and peroxyacetic acid (LA-PAA) was developed as an alternative to chlorinated water (CW) for fresh produce processing. Single strains of Lactobacillus plantarum, nonpathogenic Escherichia coli K-12, and Listeria innocua were used to demonstrate the microbial efficacy of LA-PAA. LA-PAA achieved a >7.8-log reduction of L. innocua and L. plantarum suspended in water at 4°C for 20 s, and LA, PAA, and CW achieved reductions of 0.4, 4.8, and 2.7 log, respectively. LA-PAA, when compared with LA, PAA, and CW, enhanced the reduction of L. innocua attached to romaine leaves by >2.2 log, and improved the removal of E. coli attached to spinach leaves by >2.4 log. The exponential improvement in the microbial efficacy of LA-PAA showed synergism between LA and PAA. LA-PAA microbial efficacy was inversely proportional to pH value and directly correlated with residence time and concentration. Despite an improvement in microbial reduction through the addition of surfactant to LA-PAA, the usage of surfactant in washing fresh produce was impeded by excessive foaming during actual processing. Effects of organic matter on the performance of LA-PAA were minimal. External sensory evaluations showed that LA-PAA had no negative effects on the quality of lettuce and tender leaves. Temperature-abuse studies demonstrated that LA-PAA reduced decay by ∼50% when compared with CW. Overall, these results support the premise that LA-PAA has significant potential to be an alternative to CW for fresh produce processing.

  15. H-NS mediated repression of CRISPR-based immunity in Escherichia coli K12 can be relieved by the transcription activator LeuO


    Westra, Edze Rients; Pul, Ümit; Heidrich, Nadja; Jore, Matthijs Miklas; Lundgren, Magnus; Stratmann, Thomas; Wurm, Reinhild; Raine, Amanda; Mescher, Melina; Heereveld, Luc Van; Mastop, Marieke; Wagner, E. Gerhart H.; Schnetz, Karin; Van Der Oost, John; Wagner, Rolf


    Abstract The recently discovered prokaryotic CRISPR/Cas defense system provides immunity against viral infections and plasmid conjugation. It has been demonstrated that in Escherichia coli transcription of the Cascade genes (casABCDE) and to some extent the CRISPR array, is repressed by heat-stable nucleoid-structuring (H-NS) protein, a global transcriptional repressor. Here we elaborate on the control of the E. coli CRISPR/Cas system, and study the effect on CRISPR-based anti-vira...

  16. H-NS-mediated repression of CRISPR-based immunity in Escherichia coli K12 can be relieved by the transcription activator LeuO

    NARCIS (Netherlands)

    Westra, E.R.; Pul, Ü.; Heidrich, N.; Jore, M.M.; Lundgren, N.M.J.; Stratmann, T.; Wurm, R.; Raine, A.; Mescher, M.; Heereveld, van L.; Mastop, M.; Wagner, E.G.H.; Schnetz, K.; Oost, van der J.; Wagner, R.; Brouns, S.J.J.


    The recently discovered prokaryotic CRISPR/Cas defence system provides immunity against viral infections and plasmid conjugation. It has been demonstrated that in Escherichia coli transcription of the Cascade genes (casABCDE) and to some extent the CRISPR array is repressed by heat-stable

  17. Effect of heat and radio frequency electric field treatments on membrane damage and intracellular leakage of UV-substances of Escherichia coli K-12 in apple juice (United States)

    The need for a nonthermal intervention technology that can achieve microbial safety without altering nutritional quality of liquid foods led to the development of the radio frequency electric fields (RFEF) process. Previously, we documented formation of surface blebs on Escherichia coli cells treate...

  18. Description and interpretation of adaptive evolution of Escherichia coli K-12 MG1655 by using a genome-scale in silico metabolic model. (United States)

    Fong, Stephen S; Marciniak, Jennifer Y; Palsson, Bernhard Ø


    Genome-scale in silico metabolic networks of Escherichia coli have been reconstructed. By using a constraint-based in silico model of a reconstructed network, the range of phenotypes exhibited by E. coli under different growth conditions can be computed, and optimal growth phenotypes can be predicted. We hypothesized that the end point of adaptive evolution of E. coli could be accurately described a priori by our in silico model since adaptive evolution should lead to an optimal phenotype. Adaptive evolution of E. coli during prolonged exponential growth was performed with M9 minimal medium supplemented with 2 g of alpha-ketoglutarate per liter, 2 g of lactate per liter, or 2 g of pyruvate per liter at both 30 and 37 degrees C, which produced seven distinct strains. The growth rates, substrate uptake rates, oxygen uptake rates, by-product secretion patterns, and growth rates on alternative substrates were measured for each strain as a function of evolutionary time. Three major conclusions were drawn from the experimental results. First, adaptive evolution leads to a phenotype characterized by maximized growth rates that may not correspond to the highest biomass yield. Second, metabolic phenotypes resulting from adaptive evolution can be described and predicted computationally. Third, adaptive evolution on a single substrate leads to changes in growth characteristics on other substrates that could signify parallel or opposing growth objectives. Together, the results show that genome-scale in silico metabolic models can describe the end point of adaptive evolution a priori and can be used to gain insight into the adaptive evolutionary process for E. coli.

  19. Development of a new fluorescent reporter:operator system: location of AraC regulated genes in Escherichia coli K-12. (United States)

    Sellars, Laura E; Bryant, Jack A; Sánchez-Romero, María-Antonia; Sánchez-Morán, Eugenio; Busby, Stephen J W; Lee, David J


    In bacteria, many transcription activator and repressor proteins regulate multiple transcription units that are often distally distributed on the bacterial genome. To investigate the subcellular location of DNA bound proteins in the folded bacterial nucleoid, fluorescent reporters have been developed which can be targeted to specific DNA operator sites. Such Fluorescent Reporter-Operator System (FROS) probes consist of a fluorescent protein fused to a DNA binding protein, which binds to an array of DNA operator sites located within the genome. Here we have developed a new FROS probe using the Escherichia coli MalI transcription factor, fused to mCherry fluorescent protein. We have used this in combination with a LacI repressor::GFP protein based FROS probe to assess the cellular location of commonly regulated transcription units that are distal on the Escherichia coli genome. We developed a new DNA binding fluorescent reporter, consisting of the Escherichia coli MalI protein fused to the mCherry fluorescent protein. This was used in combination with a Lac repressor:green fluorescent protein fusion to examine the spatial positioning and possible co-localisation of target genes, regulated by the Escherichia coli AraC protein. We report that induction of gene expression with arabinose does not result in co-localisation of AraC-regulated transcription units. However, measurable repositioning was observed when gene expression was induced at the AraC-regulated promoter controlling expression of the araFGH genes, located close to the DNA replication terminus on the chromosome. Moreover, in dividing cells, arabinose-induced expression at the araFGH locus enhanced chromosome segregation after replication. Regions of the chromosome regulated by AraC do not colocalise, but transcription events can induce movement of chromosome loci in bacteria and our observations suggest a role for gene expression in chromosome segregation.

  20. Overproduction, purification and structural characterization of the functional N-terminal DNA-binding domain of the fru repressor from Escherichia coli K-12. (United States)

    Scarabel, M; Penin, F; Bonod-Bidaud, C; Nègre, D; Cozzone, A J; Cortay, J C


    A DNA fragment encoding the DNA-binding domain (amino acids 1-60) of the Escherichia coli fru transcriptional regulator was cloned into the pGEX-KT vector and expressed in frame with the fused gene encoding glutathione S-transferase. The fusion protein was purified to homogeneity by affinity chromatography on immobilized glutathione, and then cleaved with thrombin. After separation by a cation-exchange chromatography step, the DNA-binding domain exhibited proper folding, as shown by proton NMR analysis. Furthermore, it showed specific interaction with the operator region of the ace operon, as checked by gel retardation and DNA methylation-protection experiments.

  1. The CytR repressor antagonizes cyclic AMP-cyclic AMP receptor protein activation of the deoCp2 promoter of Escherichia coli K-12

    DEFF Research Database (Denmark)

    Søgaard-Andersen, Lotte; Martinussen, J; Møllegaard, N E


    We have investigated the regulation of the Escherichia coli deoCp2 promoter by the CytR repressor and the cyclic AMP (cAMP) receptor protein (CRP) complexed to cAMP. Promoter regions controlled by these two proteins characteristically contain tandem cAMP-CRP binding sites. Here we show that (i) Cyt......AMP-CRP complex; (iii) introduction of point mutations in either CRP target resulted in loss of CytR regulation; and (iv) regulation by CytR of deletion mutants lacking CRP-2 could be specifically reestablished by increasing the intracellular concentration of CytR. These findings indicate that both CRP targets...

  2. A novel putrescine importer required for type 1 pili-driven surface motility induced by extracellular putrescine in Escherichia coli K-12. (United States)

    Kurihara, Shin; Suzuki, Hideyuki; Oshida, Mayu; Benno, Yoshimi


    Recently, many studies have reported that polyamines play a role in bacterial cell-to-cell signaling processes. The present study describes a novel putrescine importer required for induction of type 1 pili-driven surface motility. The surface motility of the Escherichia coli ΔspeAB ΔspeC ΔpotABCD strain, which cannot produce putrescine and cannot import spermidine from the medium, was induced by extracellular putrescine. Introduction of the gene deletions for known polyamine importers (ΔpotE, ΔpotFGHI, and ΔpuuP) or a putative polyamine importer (ΔydcSTUV) into the ΔspeAB ΔspeC ΔpotABCD strain did not affect putrescine-induced surface motility. The deletion of yeeF, an annotated putative putrescine importer, in the ΔspeAB ΔspeC ΔpotABCD ΔydcSTUV strain abolished surface motility in putrescine-supplemented medium. Complementation of yeeF by a plasmid vector restored surface motility. The surface motility observed in the present study was abolished by the deletion of fimA, suggesting that the surface motility is type 1 pili-driven. A transport assay using the yeeF(+) or ΔyeeF strains revealed that YeeF is a novel putrescine importer. The K(m) of YeeF (155 μM) is 40 to 300 times higher than that of other importers reported previously. On the other hand, the V(max) of YeeF (9.3 nmol/min/mg) is comparable to that of PotABCD, PotFGHI, and PuuP. The low affinity of YeeF for putrescine may allow E. coli to sense the cell density depending on the concentration of extracellular putrescine.

  3. A Novel Putrescine Importer Required for Type 1 Pili-driven Surface Motility Induced by Extracellular Putrescine in Escherichia coli K-12* (United States)

    Kurihara, Shin; Suzuki, Hideyuki; Oshida, Mayu; Benno, Yoshimi


    Recently, many studies have reported that polyamines play a role in bacterial cell-to-cell signaling processes. The present study describes a novel putrescine importer required for induction of type 1 pili-driven surface motility. The surface motility of the Escherichia coli ΔspeAB ΔspeC ΔpotABCD strain, which cannot produce putrescine and cannot import spermidine from the medium, was induced by extracellular putrescine. Introduction of the gene deletions for known polyamine importers (ΔpotE, ΔpotFGHI, and ΔpuuP) or a putative polyamine importer (ΔydcSTUV) into the ΔspeAB ΔspeC ΔpotABCD strain did not affect putrescine-induced surface motility. The deletion of yeeF, an annotated putative putrescine importer, in the ΔspeAB ΔspeC ΔpotABCD ΔydcSTUV strain abolished surface motility in putrescine-supplemented medium. Complementation of yeeF by a plasmid vector restored surface motility. The surface motility observed in the present study was abolished by the deletion of fimA, suggesting that the surface motility is type 1 pili-driven. A transport assay using the yeeF+ or ΔyeeF strains revealed that YeeF is a novel putrescine importer. The Km of YeeF (155 μm) is 40 to 300 times higher than that of other importers reported previously. On the other hand, the Vmax of YeeF (9.3 nmol/min/mg) is comparable to that of PotABCD, PotFGHI, and PuuP. The low affinity of YeeF for putrescine may allow E. coli to sense the cell density depending on the concentration of extracellular putrescine. PMID:21266585

  4. The organization of the fuc regulon specifying L-fucose dissimilation in Escherichia coli K12 as determined by gene cloning. (United States)

    Chen, Y M; Zhu, Y; Lin, E C


    In Escherichia coli the six known genes specifying the utilization of L-fucose as carbon and energy source cluster at 60.2 min and constitute a regulon. These genes include fucP (encoding L-fucose permease), fucI (encoding L-fucose isomerase), fucK (encoding L-fuculose kinase), fucA (encoding L-fuculose 1-phosphate aldolase), fucO (encoding L-1,2-propanediol oxidoreductase), and fucR (encoding the regulatory protein). In this study the fuc genes were cloned and their positions on the chromosome were established by restriction endonuclease and complementation analyses. Clockwise, the gene order is: fucO-fucA-fucP-fucI-fucK-fucR. The operons comprising the structural genes and the direction of transcription were determined by complementation analysis and Southern blot hybridization. The fucPIK and fucA operons are transcribed clockwise. The fucO operon is transcribed counterclockwise. The fucR gene product activates the three structural operons in trans.

  5. Implication of the E. coli K12 uvrA and recA genes in the repair of 8-methoxypsoralen-induced mono adducts and crosslinks on plasmid DNA; Implicacion de los genes uvrA de E. coli K12 en la reparacion de monoaductos y entrecruzamien tos inducidos en DNA plasmidico por 8-metoxipso raleno mas luz ultravioleta A

    Energy Technology Data Exchange (ETDEWEB)

    Paramio, J.M.; Bauluz, C.; Vidania, R. de


    Genotoxicity of psoralen damages on plasmid DNA has been studied. pBR322 DNA was randomly modified with several concentrations of 8-methoxypsoralen plus 365 nm-UV light. After transformation into E. coli strains (wild-type, uvrA and recA) plasmid survival and mutagenesis were analyzed. To study the influence of the SOS response on plasmid recovery, preirradiation of the cells was performed. In absence of cell preirradiation, crosslinks were not repaired in any strain. Mono adducts were also lethal but in part removed by the excision-repair pathway. Preirradiation of the cells significantly. increased plasmid recovery in recA+ celia. In uvrA- only the mutagenic pathway seemed to be involved in the repair of the damaged DNA. Wild type strain showed the highest increase in plasmid survival, involving the repair of mono adducts and some fraction of crosslinks mainly through an error-free repair pathway. This suggests an enhancement of the excision repair promoted by the induction of SOS functions. (Author) 32 refs.

  6. High-level expression of a bacterial laccase, CueO from Escherichia coli K12 in Pichia pastoris GS115 and its application on the decolorization of synthetic dyes. (United States)

    Ma, Xiaojian; Liu, Lu; Li, Qingqing; Liu, Yunyun; Yi, Li; Ma, Lixin; Zhai, Chao


    Laccases are oxidoreductase catalyze the oxidation of a wide range of substrates with oxygen as the electron acceptor. This report was aimed to the high-level expression of a laccase, CueO from Escherichia coli K12 in Pichia pastoris GS115 and its application on decolorization of synthetic dyes. The yacK gene coding CueO was cloned into an expression vector of Pichia pastoris, pHBM905BDM and expressed in a secretory form with Pichia pastoris GS115 as the host. The yield of the recombinant protein was 556mg/L with high-density fermentation and the enzyme activity was about 41,000U/L. The recombinant laccase was purified and characterized. Its optimum pH and temperature was 3.0 and 55°C with 2, 2'-azino-bis-(3-ethylbenzothazoline-6-sulfonic acid) (ABTS) as the substrate, respectively. This recombinant protein was thermostable and its half life at 70°C was about 60min. In the presence of natural redox mediator acetosyringone, the purified recombinant laccase decolorized 98.1% and 98.5% of Congo red, malachite green, respectively. It also decolorized 90.03% of Remazol brilliant blue R without this mediator. In addition, this enzyme was applied on the decolorization of wastewater from a textile printing factory and showed an obvious bleaching effect. Copyright © 2017. Published by Elsevier Inc.

  7. Classifying K-12 Blended Learning (United States)

    Staker, Heather; Horn, Michael B.


    The growth of online learning in the K-12 sector is occurring both remotely through virtual schools and on campuses through blended learning. In emerging fields, definitions are important because they create a shared language that enables people to talk about the new phenomena. The blended-learning taxonomy and definitions presented in this paper…

  8. California's Future: K-12 Education (United States)

    Hill, Laura; Gao, Niu; Warren, Paul


    California educates more than six million children in its K-12 public schools. More than half of these children are economically disadvantaged, and almost a quarter are not native English speakers (compared to less than one in ten nationwide). California is working to address these challenges, in part by adopting a new, simplified school finance…

  9. The Metamorphosis by K. (12)

    CERN Multimedia

    CERN Bulletin


    In the last issue of the Bulletin we reported on the first run of the new NA62 experiment. In this issue, we go behind the scenes to take a look at the production of the experiment's new kaon beam.   The start of the K12 beam line as seen during the installation of the shielding. 10-2, 10-3, 10-4, 10-5, 10-6 mbar… send in the protons! Since Thursday 1 November, the P42 beam line of the SPS has once again been sending protons to the beryllium target to produce the K12 kaon beam line eagerly awaited by the NA62 collaboration. This was no trivial matter! The first step was to clear the decks by dismantling the entire H10 beam line and NA60 experiment, as well as most of the NA48 experiment - representing some 1000 tonnes of equipment in total! Next came the complete renovation of the infrastructure, which dated back to 1979. The operation called on the expertise of virtually all branches of the EN and GS departments, as well as the Radiation Protection group: from ...

  10. Optics education for K-12 (United States)

    Bilbro, James W.; Gaines Walker, Janice M.


    The SPIE Education Committee has developed an outreach program aimed at enhancing the dissemination of information about optics to children in kindergarten through the 12th grade (K-12). The main impetus behind the program was that more practicing optical scientists and engineers would be willing to give lectures and demonstrations aimed at inspiring the next generation about optics if material could be made easily available. Consequently, three instructional `outreach kits' were assembled to use in teaching optics to kids in exciting and fun ways. These kits were beta-tested over the last two years at six different U.S. regional sites. Each `outreach kit' contained: (1) a workbook on Optical Demonstrations on the Overhead Projector; (2) a Science and Math Experience Manual: Light, Color and Their Uses; (3) The Optics Discovery Classroom Kit; (4) a slide show; and (5) a video on careers in optics. The best tests were aimed at evaluating the practical ways of utilizing the kits, developing easy-to-follow instructions for guiding others in their use and providing suggestions on modifications, additions, and deletions to the kits. This paper discuses this outreach program and provides details relative to the kit's composition and future plans.

  11. Author Reply to K12 Inc. Response (United States)

    National Education Policy Center, 2012


    K12 Inc. enrolls more public school students than any other private education management organization in the U.S. Much has been written about K12 Inc. (referred to in this report simply as "K12") by financial analysts and investigative journalists because it is a large, publicly traded company and is the dominant player in the operation…

  12. Streptococcus salivarius K12 Limits Group B Streptococcus Vaginal Colonization. (United States)

    Patras, Kathryn A; Wescombe, Philip A; Rösler, Berenice; Hale, John D; Tagg, John R; Doran, Kelly S


    Streptococcus agalactiae (group B streptococcus [GBS]) colonizes the rectovaginal tract in 20% to 30% of women and during pregnancy can be transmitted to the newborn, causing severe invasive disease. Current routine screening and antibiotic prophylaxis have fallen short of complete prevention of GBS transmission, and GBS remains a leading cause of neonatal infection. We have investigated the ability of Streptococcus salivarius, a predominant member of the native human oral microbiota, to control GBS colonization. Comparison of the antibacterial activities of multiple S. salivarius strains by use of a deferred-antagonism test showed that S. salivarius strain K12 exhibited the broadest spectrum of activity against GBS. K12 effectively inhibited all GBS strains tested, including disease-implicated isolates from newborns and colonizing isolates from the vaginal tract of pregnant women. Inhibition was dependent on the presence of megaplasmid pSsal-K12, which encodes the bacteriocins salivaricin A and salivaricin B; however, in coculture experiments, GBS growth was impeded by K12 independently of the megaplasmid. We also demonstrated that K12 adheres to and invades human vaginal epithelial cells at levels comparable to GBS. Inhibitory activity of K12 was examined in vivo using a mouse model of GBS vaginal colonization. Mice colonized with GBS were treated vaginally with K12. K12 administration significantly reduced GBS vaginal colonization in comparison to nontreated controls, and this effect was partially dependent on the K12 megaplasmid. Our results suggest that K12 may have potential as a preventative therapy to control GBS vaginal colonization and thereby prevent its transmission to the neonate during pregnancy. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  13. Role of bolA and rpoS genes in biofilm formation and adherence pattern by Escherichia coli K-12 MG1655 on polypropylene, stainless steel, and silicone surfaces. (United States)

    Adnan, Mohd; Sousa, Ana Margarida; Machado, Idalina; Pereira, Maria Olivia; Khan, Saif; Morton, Glyn; Hadi, Sibte


    Escherichia coli has developed sophisticated means to sense, respond, and adapt in stressed environment. It has served as a model organism for studies in molecular genetics and physiology since the 1960s. Stress response genes are induced whenever a cell needs to adapt and survive under unfavorable growth conditions. Two of the possible important genes are rpoS and bolA. The rpoS gene has been known as the alternative sigma (σ) factor, which controls the expression of a large number of genes, which are involved in responses to various stress factors as well as transition to stationary phase from exponential form of growth. Morphogene bolA response to stressed environment leads to round morphology of E. coli cells, but little is known about its involvement in biofilms and its development or maintenance. This study has been undertaken to address the adherence pattern and formation of biofilms by E. coli on stainless steel, polypropylene, and silicone surfaces after 24 h of growth at 37 °C. Scanning electron microscopy was used for direct examination of the cell attachment and biofilm formation on various surfaces and it was found that, in the presence of bolA, E. coli cells were able to attach to the stainless steel and silicone very well. By contrast, polypropylene surface was not found to be attractive for E. coli cells. This indicates that bolA responded and can play a major role in the presence and absence of rpoS in cell attachment.

  14. Three clustered origins of replication in a promiscuous-plasmid replicon and their differential use in a PolA+ strain and a delta PolA strain of Escherichia coli K-12.


    Banerjee, S. K.; Luck, B T; Kim, H Y; Iyer, V. N.


    A 1,197-bp region of the broad-host-range plasmid pCU1 is adequate for its replication. Analysis of replicating molecules containing this region reveals three clustered origins of vegetative replication and replication proceeds bidirectionally from each in a theta mode. In an Escherichia coli polymerase I deletion mutant, utilization of one of these three origins was not detected. The potentiality for origin utilization may therefore be a determinant of replicon host range.

  15. Three clustered origins of replication in a promiscuous-plasmid replicon and their differential use in a PolA+ strain and a delta PolA strain of Escherichia coli K-12. (United States)

    Banerjee, S K; Luck, B T; Kim, H Y; Iyer, V N


    A 1,197-bp region of the broad-host-range plasmid pCU1 is adequate for its replication. Analysis of replicating molecules containing this region reveals three clustered origins of vegetative replication and replication proceeds bidirectionally from each in a theta mode. In an Escherichia coli polymerase I deletion mutant, utilization of one of these three origins was not detected. The potentiality for origin utilization may therefore be a determinant of replicon host range.

  16. K-12 Educational Outcomes of Immigrant Youth

    National Research Council Canada - National Science Library

    Robert Crosnoe; Ruth N. López Turley


    The children from immigrant families in the United States make up a historically diverse population, and they are demonstrating just as much diversity in their experiences in the K-12 educational system...

  17. Nebraska Science Standards: Grades K-12 (United States)

    Nebraska Department of Education, 2010


    This publication presents the Nebraska Science Standards for Grades K-12. The standards are presented according to the following grades: (1) Grades K-2; (2) Grades 3-5; (3) Grades 6-8; and (4) Grades 9-12.

  18. Investigating the Potential of MOOCs in K-12 Teaching and Learning Environments (United States)

    Nigh, Jennifer; Pytash, Kristine E.; Ferdig, Richard E.; Merchant, William


    The massive open online course (MOOC) is a relatively new concept in K-12 teaching and learning environments. Although significant work has been done with MOOCs since 2008, it has only been recently that MOOCs have been studied with K-12 populations. The purpose of this study was to further examine the motivation of K-12 students enrolled in a…

  19. K-12 Teaching and Physics Enrollment

    CERN Document Server

    Masood, Samina S


    We have collected and analyzed the relevant data from public schools in greater Houston area of Texas. Based and analyzed. Since the data is only limited to a few school, we are still working on getting more data so that we can compare and contrast the results adequately and understand the core of the enrollment issue at the national level. However, based on the raw data and partial analysis, we propose a few recommendations towards the improvement of science education in Texas Schools, in general, and greater Houston area schools in particular. Our results indicate that the quality of science education can be improved significantly if we focus on the improvement of high school education or even intermediate schools when students are first time exposed to science in a little technical way. Simply organizing teacher training programs at K-12 level as school education plays a pivotal role in the decrease in physics enrollment at the higher level. Similar analysis can actually be generalized to other states to f...

  20. Effect of Global Regulators RpoS and Cyclic-AMP/CRP on the Catabolome and Transcriptome of Escherichia coli K12 during Carbon- and Energy-Limited Growth.

    Directory of Open Access Journals (Sweden)

    Alessandro G Franchini

    Full Text Available For heterotrophic microbes, limited availability of carbon and energy sources is one of the major nutritional factors restricting the rate of growth in most ecosystems. Physiological adaptation to this hunger state requires metabolic versatility which usually involves expression of a wide range of different catabolic pathways and of high-affinity carbon transporters; together, this allows for simultaneous utilization of mixtures of carbonaceous compounds at low concentrations. In Escherichia coli the stationary phase sigma factor RpoS and the signal molecule cAMP are the major players in the regulation of transcription under such conditions; however, their interaction is still not fully understood. Therefore, during growth of E. coli in carbon-limited chemostat culture at different dilution rates, the transcriptomes, expression of periplasmic proteins and catabolomes of strains lacking one of these global regulators, either rpoS or adenylate cyclase (cya, were compared to those of the wild-type strain. The inability to synthesize cAMP exerted a strong negative influence on the expression of alternative carbon source uptake and degradation systems. In contrast, absence of RpoS increased the transcription of genes belonging to high-affinity uptake systems and central metabolism, presumably due to reduced competition of σ(D with σ(S. Phenotypical analysis confirmed this observation: The ability to respire alternative carbon substrates and to express periplasmic high-affinity binding proteins was eliminated in cya and crp mutants, while these properties were not affected in the rpoS mutant. As expected, transcription of numerous stress defence genes was negatively affected by the rpoS knock-out mutation. Interestingly, several genes of the RpoS stress response regulon were also down-regulated in the cAMP-negative strain indicating a coordinated global regulation. The results demonstrate that cAMP is crucial for catabolic flexibility during slow

  1. Development of K-12 Engineering Outreach Materials (United States)

    Jordan, William


    Six modules were created that can be used in K-12 classes to introduce students to what engineers can do at NASA.The purpose of this project was to create outreach materials for the classroom. To make it appealing to students, many color NASA photographs are used to illustrate NASA applications.Student experiments are described that can be performed to illustrate topics.

  2. Copyright Updates for K-12 Librarians (United States)

    Johnson, Wendell G.


    Copyright concerns continue to bedevil K-12 librarians, who are often called upon to act as the copyright officers in public schools. This article describes recent copyright developments of concern to these librarians in three areas: a recent court case involving a university library, pending legislation supported by ALA, and a regulatory update.…

  3. Physical Education Curriculum Framework K-12. (United States)

    Tennessee State Dept. of Education, Nashville.

    This monograph presents a framework for physical education programs in Tennessee for grades K-12. The framework covers four areas: (1) games/sports; (2) gymnastics; (3) physical fitness; and (4) rhythmic movement. The goals and objectives for each of these areas are outlined and described for all grade levels. (JD)

  4. Approaching K-12 Online Education in Pennsylvania (United States)

    Vadell, Kathryn


    The purpose of this study is to determine how K-12 schools are addressing the need to accommodate online learners in Pennsylvania. It is built upon a review of literature focusing on educational legislation, the personalization of online learning and online learning solutions. The study posed 21 questions utilizing a mixed methods approach to…

  5. Developing Open Education Literacies with Practicing K-12 Teachers

    Directory of Open Access Journals (Sweden)

    Royce M Kimmons


    Full Text Available This study seeks to understand how to use formal learning activities to effectively support the development of open education literacies among K-12 teachers. Considering pre- and post-surveys from K-12 teachers (n = 80 who participated in a three-day institute, this study considers whether participants entered institutes with false confidence or misconceptions related to open education, whether participant knowledge grew as a result of participation, whether takeaways matched expectations, whether time teaching (i.e., teacher veterancy impacted participant data, and what specific evaluation items influenced participants’ overall evaluations of the institutes. Results indicated that 1 participants entered the institutes with misconceptions or false confidence in several areas (e.g., copyright, fair use, 2 the institute was effective for helping to improve participant knowledge in open education areas, 3 takeaways did not match expectations, 4 time teaching did not influence participant evaluations, expectations, or knowledge, and 5 three specific evaluation items significantly influenced overall evaluations of the institute: learning activities, instructor, and website / online resources. Researchers conclude that this type of approach is valuable for improving K-12 teacher open education literacies, that various misconceptions must be overcome to support large-scale development of open education literacies in K-12, and that open education advocates should recognize that all teachers, irrespective of time teaching, want to innovate, utilize open resources, and share in an open manner.

  6. Significance of Viable but Nonculturable Escherichia coli: Induction, Detection, and Control. (United States)

    Ding, Tian; Suo, Yuanjie; Xiang, Qisen; Zhao, Xihong; Chen, Shiguo; Ye, Xingqian; Liu, Donghong


    Diseases caused by foodborne or waterborne pathogens are emerging. Many pathogens can enter into the viable but nonculturable (VBNC) state, which is a survival strategy when exposed to harsh environmental stresses. Pathogens in the VBNC state have the ability to evade conventional microbiological detection methods, posing a significant and potential health risk. Therefore, controlling VBNC bacteria in food processing and the environment is of great importance. As the typical one of the gram-negatives, Escherichia coli (E. coli) is a widespread foodborne and waterborne pathogenic bacterium and is able to enter into a VBNC state in extreme conditions (similar to the other gram-negative bacteria), including inducing factors and resuscitation stimulus. VBNC E. coli has the ability to recover both culturability and pathogenicity, which may bring potential health risk. This review describes the concrete factors (nonthermal treatment, chemical agents, and environmental factors) that induce E. coli into the VBNC state, the condition or stimulus required for resuscitation of VBNC E. coli, and the methods for detecting VBNC E. coli. Furthermore, the mechanism of genes and proteins involved in the VBNC E. coli is also discussed in this review.

  7. Cellular chain formation in Escherichia coli biofilms

    DEFF Research Database (Denmark)

    Vejborg, Rebecca Munk; Klemm, Per


    In this study we report on a novel structural phenotype in Escherichia coli biofilms: cellular chain formation. Biofilm chaining in E. coli K-12 was found to occur primarily by clonal expansion, but was not due to filamentous growth. Rather, chain formation was the result of intercellular......; type I fimbriae expression significantly reduced cellular chain formation, presumably by steric hindrance. Cellular chain formation did not appear to be specific to E coli K-12. Although many urinary tract infection (UTI) isolates were found to form rather homogeneous, flat biofilms, three isolates...

  8. K-12 educational outcomes of immigrant youth. (United States)

    Crosnoe, Robert; Turley, Ruth N López


    The children from immigrant families in the United States make up a historically diverse population, and they are demonstrating just as much diversity in their experiences in the K-12 educational system. Robert Crosnoe and Ruth López Turley summarize these K-12 patterns, paying special attention to differences in academic functioning across segments of the immigrant population defined by generational status, race and ethnicity, and national origin. A good deal of evidence points to an immigrant advantage in multiple indicators of academic progress, meaning that many youths from immigrant families outperform their peers in school. This apparent advantage is often referred to as the immigrant paradox, in that it occurs despite higher-than-average rates of social and economic disadvantages in this population as a whole. The immigrant paradox, however, is more pronounced among the children of Asian and African immigrants than other groups, and it is stronger for boys than for girls. Furthermore, evidence for the paradox is far more consistent in secondary school than in elementary school. Indeed, school readiness appears to be one area of potential risk for children from immigrant families, especially those of Mexican origin. For many groups, including those from Latin America, any evidence of the immigrant paradox usually emerges after researchers control for family socioeconomic circumstances and youths' English language skills. For others, including those from Asian countries, it is at least partially explained by the tendency for more socioeconomically advantaged residents of those regions to leave their home country for the United States. Bilingualism and strong family ties help to explain immigrant advantages in schooling; school, community, and other contextual disadvantages may suppress these advantages or lead to immigrant risks. Crosnoe and Turley also discuss several policy efforts targeting young people from immigrant families, especially those of Latin

  9. Applying the Quadratic Usage Framework to Research on K-12 STEM Digital Learning Resources (United States)

    Luetkemeyer, Jennifer R.


    Numerous policymakers have called for K-12 educators to increase their effectiveness by transforming science, technology, engineering, and mathematics (STEM) learning and teaching with digital resources and tools. In this study we outline the significance of studying pressing issues related to use of digital resources in the K-12 environment and…

  10. The K-12 Educational Technology Value Chain: Apps for Kids, Tools for Teachers and Levers for Reform (United States)

    Pierce, Glenn L.; Cleary, Paul F.


    Historically implementing, maintaining and managing educational technology has been difficult for K-12 educational systems. Consequently, opportunities for significant advances in K-12 education have often gone unrealized. With the maturation of Internet delivered services along with K-12 institutional trends, educational technologies are poised…

  11. Colorado K-12 & School Choice Survey: What Do Voters Say about K-12 Education? Polling Paper No. 26 (United States)

    DiPerna, Paul


    The purpose of the "Colorado K-12 & School Choice Survey" is to measure public opinion on, and in some cases awareness or knowledge of, a range of K-12 education topics and school choice reforms. A total of 601 telephone interviews were completed from August 29 to September 16, 2015, with questions on the direction of K-12 education,…

  12. Detecting the Significant Flux Backbone of Escherichia coli metabolism. (United States)

    Güell, Oriol; Sagués, Francesc; Serrano, M Ángeles


    The heterogeneity of computationally predicted reaction fluxes in metabolic networks within a single flux state can be exploited to detect their significant flux backbone. Here, we disclose the backbone of Escherichia coli, and compare it with the backbones of other bacteria. We find that, in general, the core of the backbones is mainly composed of reactions in energy metabolism corresponding to ancient pathways. In E. coli, the synthesis of nucleotides and the metabolism of lipids form smaller cores which rely critically on energy metabolism. Moreover, the consideration of different media leads to the identification of pathways sensitive to environmental changes. The metabolic backbone of an organism is thus useful to trace simultaneously both its evolution and adaptation fingerprints. © 2017 The Authors FEBS Letters published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.

  13. Synergistic effects in mixed Escherichia coli biofilms

    DEFF Research Database (Denmark)

    Reisner, A.; Holler, B.M.; Molin, Søren


    the pathways governing development of more complex heterogeneous communities. In this study, we established a laboratory model where biofilm-stimulating effects due to interactions between genetically diverse strains of Escherichia coli were monitored. Synergistic induction of biofilm formation resulting from...... the cocultivation of 403 undomesticated E. coli strains with a characterized E. coli K-12 strain was detected at a significant frequency. The survey suggests that different mechanisms underlie the observed stimulation, yet synergistic development of biofilm within the subset of E. coli isolates (n = 56) exhibiting...... the strongest effects was most often linked to conjugative transmission of natural plasmids carried by the E. coli isolates (70%). Thus, the capacity of an isolate to promote the biofilm through cocultivation was (i) transferable to the K-12 strain, (ii) was linked with the acquisition of conjugation genes...

  14. Attaching and effacing Escherichia coli isolates from Danish children: clinical significance and microbiological characteristics

    DEFF Research Database (Denmark)

    Jensen, C; Ethelberg, S; Olesen, B


    This study describes the prevalence, clinical manifestations and microbiological characteristics of attaching and effacing Escherichia coli isolates, i.e., enteropathogenic E. coli (EPEC) belonging to the classical EPEC serotypes, non-EPEC attaching and effacing E. coli (A/EEC) and verocytotoxin......-producing E. coli (VTEC), isolated in a case-control study of Danish children aged

  15. Influences of Globalization on K-12 Language Teacher Education Programs (United States)

    Singh, Navin Kumar


    The purpose of this study was to explore the effects of globalization on K-12 language teacher education at Northern Arizona University (NAU) in terms of multilingual practices in the US, with reference to an English-only-state, Arizona. This study explored influences of globalization on K-12 language education practices in the US through teacher…

  16. Keeping Pace with K-12 Online Learning, 2016 (United States)

    Gemin, Butch; Pape, Larry


    "Keeping Pace with K-12 Online Learning 2016" marks the thirteenth consecutive year Evergreen has published its annual research of the K-12 education online learning market. The thirteen years of researching, writing and publishing this report represents a time of remarkable change. There has been a constant presence that has become the…

  17. Diarrhoeagenic Escherichia coli are not a significant cause of diarrhoea in hospitalised children in Kuwait

    Directory of Open Access Journals (Sweden)

    Pacsa Alexander S


    Full Text Available Abstract Background The importance of diarrhoeagenic Escherichia coli (DEC infections in the Arabian Gulf including Kuwait is not known. The prevalence of DEC (enterotoxigenic [ETEC], enteropathogenic [EPEC], enteroinvasive [EIEC], enterohemorrhagic [EHEC] and enteroaggregative [EAEC] was studied in 537 children ≤ 5 years old hospitalised with acute diarrhoea and 113 matched controls from two hospitals during 2005–07 by PCR assays using E. coli colony pools. Results The prevalence of DEC varied from 0.75% for EHEC to 8.4% for EPEC (mostly atypical variety in diarrhoeal children with no significant differences compared to that in control children (P values 0.15 to 1.00. Twenty-seven EPEC isolates studied mostly belonged to non-traditional serotypes and possessed β and θ intimin subtypes. A total of 54 DEC isolates from diarrhoeal children and 4 from controls studied for antimicrobial susceptibility showed resistance for older antimicrobials, ampicillin (0 to 100%, tetracycline (33 to 100% and trimethoprim (22.2 to 100%; 43.1% of the isolates were multidrug-resistant (resistant to 3 or more agents. Six (10.4% DEC isolates produced extended spectrum β-lactamases and possessed genetic elements (blaCTX-M, blaTEM and ISEcp1 associated with them. Conclusion We speculate that the lack of significant association of DEC with diarrhoea in children in Kuwait compared to countries surrounding the Arabian Gulf Region may be attributable to high environmental and food hygiene due to high disposable income in Kuwait.

  18. Undergraduate interest in K--12 teaching and the perceived 'climate' for the K--12 education profession in the natural sciences (United States)

    Gerdeman, Robert Dean

    Previous research suggests that the natural science setting in universities does not offer a supportive environment for undergraduates interested in K--12 education careers, an important problem given the need for K--12 science teachers. A mixed-method approach was used to examine student perspectives toward K--12 education careers, and the influence of the college experience on perspectives, at a public research university. Quantitative data come from a cross-sectional survey sample (N = 444) of upper-division natural science majors in the university. The survey focused on student background characteristics, undergraduate experiences, perceptions of the college environment, career interests, and satisfaction. Pursuit of K--12 education as a top current career choice was rare among the respondents (3.6%). However, about one-fourth of them indicated some interest in this career and overall interest increased slightly during the college experience. Based on student perceptions, K--12 education was substantially less emphasized within the natural sciences than other career fields. Regression analyses revealed that the most important predictors (aside from initial career interests) of interest in and attitude toward K--12 teaching were self-concept and personality measures. Several college experience measures were also predictors, including perceptions about faculty and peers in the natural sciences. The effect of college experiences differed for students initially more inclined toward K--12 teaching, who reported a net decrease in interest, versus those more disinclined, who reported a net gain in interest. Satisfaction with the college experience was similar for the two groups. Qualitative data come from follow-up interviews conducted with eight survey respondents who recalled a top choice of K--12 teaching upon entering college but had decided to pursue another career. These students perceived other career fields to offer better professional opportunities for

  19. Media Literacy and the K-12 Content Areas (United States)

    Hobbs, Renee


    Media literacy education is being explored by scholars in many different fields (including education, literature, media studies, psychology, and public health), but there is less evidence of implementations occurring in K-12 settings. With more than 1.3 million teachers in U.S. public schools, it is impossible to estimate the extent to which the…

  20. Information Security Management Practices of K-12 School Districts (United States)

    Nyachwaya, Samson


    The research problem addressed in this quantitative correlational study was the inadequacy of sound information security management (ISM) practices in K-12 school districts, despite their increasing ownership of information assets. Researchers have linked organizational and sociotechnical factors to the implementation of information security…

  1. Engaging K-12 Language Learners in Media Literacy (United States)

    Egbert, Joy; Neville, Chon


    Calls to integrate media literacy into K-12 language classrooms appear to have gone largely unheeded. However, media literacy skills are seen as crucial for 21st-century learners. This article answers the calls for a focus on media literacy in the language classroom by addressing both why and how systematic attention might be brought to this issue…

  2. Education Nation: Obama, Romney Outline Different K-12, Postsecondary Priorities (United States)

    Dervarics, Charles


    With negative ads already rampant on radio and TV, it's clear that President Obama and Republican presidential nominee Mitt Romney differ on most issues. That statement carries over to education as well, as both offer starkly different views on K-12 and higher education policy for the fall campaign. Obama is touting a large increase in Pell Grants…

  3. Leadership Analysis in K-12 Case Study: "Divided Loyalties" (United States)

    Alsubaie, Merfat Ayesh


    This report mainly aims to provide a critical and in-depth analysis of the K-12 Case, "Divided Loyalty" by Holy and Tartar (2004). The case recounts how the manifestation of inadequate leadership skills in a school setting could affect negatively the performance of students.

  4. Inspiring the Next Generation: Astronomy Catalyzes K12 STEM Education (United States)

    Borders, Kareen; Thaller, Michelle; Winglee, Robert; Borders, Kyla


    K-12 educators need effective and relevant astronomy professional development. NASA's Mission Science provides innovative and accessible opportunities for K-12 teachers. Science questions involve scale and distance, including Moon/Earth scale, solar system scale, and distance of objects in the universe. Teachers can gain an understanding of basic telescopes, the history of telescopes, ground and satellite based telescopes, and models of JWST Telescope. An in-depth explanation of JWST and Spitzer telescopes gave participants background knowledge for infrared astronomy observations. During teacher training, we taught the electromagnetic spectrum through interactive stations. The stations included an overview via lecture and power point, the use of ultraviolet beads to determine ultraviolet exposure, the study of lenticulars and diagramming of infrared data, looking at visible light through diffraction glasses and diagramming the data, protocols for using astronomy based research in the classroom, and infrared thermometers to compare environmental conditions around the observatory. An overview of LIDAR physics was followed up by a simulated LIDAR mapping of the topography of Mars.We will outline specific steps for K-12 infrared astronomy professional development, provide data demonstrating the impact of the above professional development on educator understanding and classroom use, and detail future plans for additional K-12 professional development.Funding was provided by Washington STEM, NASA, and the Washington Space Grant Consortium.

  5. Transforming K-12 Rural Education through Blended Learning: Teacher Perspectives (United States)

    Kellerer, Paula; Kellerer, Eric; Werth, Eric; Werth, Lori; Montgomery, Danielle; Clyde, Rozella; Cozart, Joe; Creach, Laura; Hibbard, Laura; LaFrance, Jason; Rupp, Nadine; Walker, Niki; Carter, Theresa; Kennedy, Kathryn


    A qualitative study exploring rural teacher perspectives on the impact of blended learning on students and teachers was conducted in Idaho during the Fall of 2013. Researchers from Northwest Nazarene University's DOCEO Center in partnership with Idaho Digital Learning Academy (IDLA) and the International Association for K-12 Online Learning…

  6. Green Power Partnership Top 30 K-12 Schools (United States)

    The U.S. EPA's Green Power Partnership is a voluntary program designed to reduce the environmental impact of electricity generation by promoting renewable energy. On this list are the largest green power users among K-12 school partners within the GPP.

  7. Project WILD Aquatic K-12 Curriculum and Activity Guide (United States)

    Council for Environmental Education, 2011


    The "Project WILD Aquatic K-12 Curriculum and Activity Guide" emphasizes aquatic wildlife and aquatic ecosystems. It is organized in topic units and is based on the Project WILD conceptual framework. Because these activities are designed for integration into existing courses of study, instructors may use one or many Project WILD Aquatic activities…

  8. Exploring the Effectiveness of Online Education in K-12 Environments (United States)

    Heafner, Tina L., Ed.; Hartshorne, Richard, Ed.; Petty, Teresa, Ed.


    The integration of technology in classrooms is rapidly emerging as a way to provide more educational opportunities for students. As virtual learning environments become more popular, evaluating the impact of this technology on student success is vital. "Exploring the Effectiveness of Online Education in K-12 Environments" combines…

  9. Designing GIS Learning Materials for K-12 Teachers (United States)

    Hong, Jung Eun


    Although previous studies have proven the usefulness and effectiveness of geographic information system (GIS) use in the K-12 classroom, the rate of teacher adoption remains low. The identified major barrier to its use is a lack of teachers' background and experience. To solve this limitation, many organisations have provided GIS-related teacher…

  10. K-12 Marketplace Sees Major Flow of Venture Capital (United States)

    Ash, Katie


    The flow of venture capital into the K-12 education market has exploded over the past year, reaching its highest transaction values in a decade in 2011, industry observers say. They attribute that rise to such factors as a heightened interest in educational technology; the decreasing cost of electronic devices such as tablet computers, laptops,…

  11. Best Practices in Administration of K-12 Dance Programs (United States)

    Henneman, Suzanne E.


    The role of administering K-12 dance education programs is both exciting and invigorating. Being part of the decision-making process, problem solving with teams of colleagues, establishing routines and initiatives, creating "something from nothing," and watching programs grow is appealing to dance teachers as creative and critical…

  12. School Hopscotch: A Comprehensive Review of K-12 Student Mobility in the United States (United States)

    Welsh, Richard O.


    This article provides an integrative review of the extant literature on K-12 student mobility in the United States. Student mobility is a widespread phenomenon with significant policy implications. Changing schools is most prevalent among minority and low-income students in urban school districts. There is an ongoing debate about whether student…

  13. Perceptions of Professional and Educational Skills Learning Opportunities Made Available through K-12 Robotics Programming (United States)

    Bakke, Christine K.


    The purpose of this study is to examine whether participation in robotics provides opportunities for educational and professional skill development, significant enough to merit the recommendation of robotics courses as a part of mainstream curriculum offerings in K-12 schools. This non-experimental, mixed methods study examined current junior high…

  14. A Case Study of Rural New Mexico K-12 Teachers' Perceptions of Standardized Testing (United States)

    Hite-Pope, Kim


    The purpose of this paper was to examine K-12 teachers' classroom experiences with standardized testing in rural New Mexico schools. Standardized tests have significantly changed the landscape of education with the use of students' test scores as a determining factor for advancement or failure for teachers (Simpson, Lacava, & Graner, 2013).…

  15. Active Commuting among K-12 Educators: A Study Examining Walking and Biking to Work

    Directory of Open Access Journals (Sweden)

    Melissa Bopp


    Full Text Available Background. Walking and biking to work, active commuting (AC is associated with many health benefits, though rates of AC remain low in the US. K-12 educators represent a significant portion of the workforce, and employee health and associated costs may have significant economic impact. Therefore, the purpose of this study was to examine the current rates of AC and factors associated with AC among K-12 educators. Methods. A volunteer sample of K-12 educators ( was recruited to participate in an online survey. Participants responded about AC patterns and social ecological influences on AC (individual, interpersonal, institutional, community, and environmental factors. -tests and ANOVAs examined trends in AC, and Pearson correlations examined the relationship between AC and dependent variables. Multiple regression analysis determined the relative influence of individual, interpersonal, institutional, community, and environmental levels on AC. Results. Participants actively commuted times/week. There were several individual, interpersonal, institutional, community, and environmental factors significantly related to AC. The full model explained 60.8% of the variance in AC behavior. Conclusions. This study provides insight on the factors that determine K-12 educators mode of commute and provide some insight for employee wellness among this population.

  16. Antibacterial Activities of Ankaferd Hemostat (ABS) on Shiga Toxin-Producing Escherichia coli and Other Pathogens Significant in Foodborne Diseases. (United States)

    Koluman, Ahmet; Akar, Nejat; Haznedaroğlu, İbrahim C


    Ankaferd hemostat (Ankaferd Blood Stopper®, ABS)-induced pharmacological modulation of essential erythroid proteins can cause vital erythroid aggregation via acting on fibrinogen gamma. Topical endoscopic ABS application is effective in the controlling of gastrointestinal (GI) system hemorrhages and/or infected GI wounds. Escherichia coli O157:H7, the predominant serotype of enterohemorrhagic E. coli, is a cause of both outbreaks and sporadic cases of hemorrhagic colitis. The aim of this study is to examine the effects of ABS on 6 different Shiga toxigenic E. coli serotypes including O26, O103, O104, O111, O145, and O157 and on other pathogens significant in foodborne diseases, such as Salmonella Typhimurium, Campylobacter jejuni, and Listeria monocytogenes, were also assessed. All strains were applied with different amounts of ABS and antimicrobial effect was screened. S. Typhimurium groups were screened for survival using the fluorescence in situ hybridization technique. The relative efficacy of ABS solutions to achieve significant logarithmic reduction in foodborne pathogens E. coli O157:H7 and non-O157 serogroups and other emerging foodborne pathogens is demonstrated in this study. ABS has antibacterial effects. Our present study indicated for the first time that ABS may act against E. coli O157:H7, which is a cause of thrombotic thrombocytopenic purpura, hemolytic-uremic syndrome, and hemorrhagic colitis. The interrelationships between colitis, infection, and hemostasis within the context of ABS application should be further investigated in future studies.

  17. Technical Feasibility Study for Zero Energy K-12 Schools

    Energy Technology Data Exchange (ETDEWEB)

    Bonnema, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Goldwasser, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Torcellini, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Pless, Shanti [National Renewable Energy Lab. (NREL), Golden, CO (United States); Studer, Daniel [National Renewable Energy Lab. (NREL), Golden, CO (United States)


    This technical feasibility study provides documentation and research results supporting a possible set of strategies to achieve source zero energy K-12 school buildings as defined by the U.S. Department of Energy (DOE) zero energy building (ZEB) definition (DOE 2015a). Under this definition, a ZEB is an energy-efficient building in which, on a source energy basis, the actual annual delivered energy is less than or equal to the on-site renewable exported energy.

  18. Involving Practicing Scientists in K-12 Science Teacher Professional Development (United States)

    Bertram, K. B.


    The Science Teacher Education Program (STEP) offered a unique framework for creating professional development courses focused on Arctic research from 2006-2009. Under the STEP framework, science, technology, engineering, and math (STEM) training was delivered by teams of practicing Arctic researchers in partnership with master teachers with 20+ years experience teaching STEM content in K-12 classrooms. Courses based on the framework were offered to educators across Alaska. STEP offered in-person summer-intensive institutes and follow-on audio-conferenced field-test courses during the academic year, supplemented by online scientist mentorship for teachers. During STEP courses, teams of scientists offered in-depth STEM content instruction at the graduate level for teachers of all grade levels. STEP graduate-level training culminated in the translation of information and data learned from Arctic scientists into standard-aligned lessons designed for immediate use in K-12 classrooms. This presentation will focus on research that explored the question: To what degree was scientist involvement beneficial to teacher training and to what degree was STEP scientist involvement beneficial to scientist instructors? Data sources reveal consistently high levels of ongoing (4 year) scientist and teacher participation; high STEM content learning outcomes for teachers; high STEM content learning outcomes for students; high ratings of STEP courses by scientists and teachers; and a discussion of the reasons scientists indicate they benefited from STEP involvement. Analyses of open-ended comments by teachers and scientists support and clarify these findings. A grounded theory approach was used to analyze teacher and scientist qualitative feedback. Comments were coded and patterns analyzed in three databases. The vast majority of teacher open-ended comments indicate that STEP involvement improved K-12 STEM classroom instruction, and the vast majority of scientist open-ended comments

  19. Females and STEM: Determining the K-12 Experiences that Influenced Women to Pursue STEM Fields (United States)

    Petersen, Anne Marie

    In the United States, careers in the fields of Science, Technology, Engineering, and Mathematics (STEM) are increasing yet there are not enough trained personnel to meet this demand. In addition, of those that seek to pursue STEM fields in the United States, only 26% are female. In order to increase the number of women seeking STEM based bachelor's degrees, K-12 education must provide a foundation that prepares students for entry into these fields. The purpose of this phenomenological study was to determine the perceived K-12 experiences that influenced females to pursue a STEM field. Twelve college juniors or seniors seeking a degree in Biology, Mathematics, or Physics were interviewed concerning their K-12 experiences. These interviews were analyzed and six themes emerged. Teacher passion and classroom characteristics such as incorporating challenging activities played a significant role in the females' decisions to enter STEM fields. Extra-curricular activities such as volunteer and mentor opportunities and the females' need to benefit others also influenced females in their career choice. Both the formal (within the school) and informal (outside of the traditional classroom) pipeline opportunities that these students encountered helped develop a sense of self-efficacy in science and mathematics; this self-efficacy enabled them to persist in pursuing these career fields. Several participants cited barriers that they encountered in K-12 education, but these barriers were primarily internal as they struggled with overcoming self-imposed obstacles in learning and being competitive in the mathematics and science classrooms. The experiences from these female students can be used by K-12 educators to prepare and encourage current female students to enter STEM occupations.

  20. Infrared Astronomy Professional Development for K-12 Educators: WISE Telescope (United States)

    Borders, Kareen; Mendez, B. M.


    K-12 educators need effective and relevant astronomy professional development. WISE Telescope (Wide-Field Infrared Survey Explorer) and Spitzer Space Telescope Education programs provided an immersive teacher professional development workshop at Arecibo Observatory in Puerto Rico during the summer of 2009. As many common misconceptions involve scale and distance, teachers worked with Moon/Earth scale, solar system scale, and distance of objects in the universe. Teachers built and used basic telescopes, learned about the history of telescopes, explored ground and satellite based telescopes, and explored and worked on models of WISE Telescope. An in-depth explanation of WISE and Spitzer telescopes gave participants background knowledge for infrared astronomy observations. We taught the electromagnetic spectrum through interactive stations. The stations included an overview via lecture and power point, the use of ultraviolet beads to determine ultraviolet exposure, the study of WISE lenticulars and diagramming of infrared data, listening to light by using speakers hooked up to photoreceptor cells, looking at visible light through diffraction glasses and diagramming the data, protocols for using astronomy based research in the classroom, and infrared thermometers to compare environmental conditions around the observatory. An overview of LIDAR physics was followed up by a simulated LIDAR mapping of the topography of Mars. We will outline specific steps for K-12 infrared astronomy professional development, provide data demonstrating the impact of the above professional development on educator understanding and classroom use, and detail future plans for additional K-12 professional development. Funding was provided by WISE Telescope, Spitzer Space Telescope, Starbucks, Arecibo Observatory, the American Institute of Aeronautics and Astronautics, and the Washington Space Grant Consortium.

  1. AIAA Educator Academy: Enriching STEM Education for K-12 Students (United States)

    Slagle, E.; Bering, E. A.; Longmier, B. W.; Henriquez, E.; Milnes, T.; Wiedorn, P.; Bacon, L.


    Educator Academy is a K-12 STEM curriculum developed by the STEM K-12 Outreach Committee of the American Institute of Aeronautics and Astronautics (AIAA). Consisting of three independent curriculum modules, K-12 students participate in inquiry-based engineering challenges to improve critical thinking skills and enhance problem solving skills. The Mars Rover Celebration Curriculum Module is designed for students in grades 3-8. Throughout this module, students learn about Mars and the solar system. Working with given design criteria, students work in teams to do basic research about Mars that will determine the operational objectives and structural features of their rover. Then, students participate in the design and construction of a model of a mock-up Mars Rover to carry out a specific science mission on the surface of Mars. At the end of this project, students have the opportunity to participate in a regional capstone event where students share their rover designs and what they have learned. The Electric Cargo Plan Curriculum Module is designed for students in grades 6-12. Throughout this module, students learn about aerodynamics and the four forces of flight. Working individually or in teams, students design and construct an electrically-powered model aircraft to fly a tethered flight of at least one lap without cargo, followed by a second tethered flight of one lap carrying as much cargo as possible. At the end of this project, students have the opportunity to participate in a regional capstone event where students share what they have learned and compete with their different cargo plane designs. The Space Weather Balloon Curriculum Module is designed for students in grades 9-12. Throughout this module, students learn and refine physics concepts as well as experimental research skills. Students participate in project-based learning that is experimental in nature. Students are engaged with the world around them as they collaborate to launch a high altitude

  2. The importance of terminology in teaching K-12 science (United States)

    Yager, Robert E.

    Several recent reports concerning the status of science education in K-12 classrooms have emphasized the centrality of textbooks to instruction. Some initial investigations of the nature of textbooks have suggested that typically more new words and terms are introduced than one would expect to find in a similar time frame as foreign languages are studied. This is a review of these initial studies, a review of the studies of mastery of vocabulary in foreign languages, and a review of general research concerning the vocabulary development, especially as it pertains to reading. Twenty-five of the most commonly used textbooks in K-12 science classrooms are analyzed in terms of the occurrence of special/technical words. The number of words introduced at every level is considerable-often more than would be required if a new language were being introduced. In addition, the number of new words in science often approaches the total number that could be expected in terms of total vocabulary increase at a given grade level for a given student. There is strong evidence that one major fact of the current crisis in science education is the considerable emphasis upon words/terms/definitions as the primary ingredient of science-at least the science that a typical student encounters and that he/she is expected to master.

  3. Communicating Regional Geology and Geohazards to K-12 Teachers (United States)

    Pratt-Sitaula, B.; Butler, R. F.; Whitman, J. M.; Granshaw, F. D.; Magura, B.; Hedeen, C.; Groom, R.; Thompson, D.; Johnson, J. A.


    The Teachers on the Leading Edge (TOTLE) program has designed an innovative model for middle school teacher professional development related to Pacific NW plate margin hazards and EarthScope science. The program has been effective at improving teacher knowledge and confidence and has led to high rates of curricular implementation. The elements particularly key to success are: a) facilitation team with broad expertise in both geoscience and education; b) regional team format that encouraged learning community development; c) teachers' desire to focus on regional geologic hazards; d) significant use of animations and field trips to aid in "visualization" of processes; and e) extensive "kit" of teaching materials for easy classroom transfer. The 1-week workshops were held in summer 2008-2010 and 35 Pacific NW middle school teachers attended each year. Geoscientists from universities and research institutions conducted the field trips and content sessions. Master K-12 Earth science teachers designed or modified curricular materials and led the teaching implementation sessions. Each year, the teachers were divided into 5 regional teams led by geoscience educator team leaders (community college instructors or similar). Teachers were surveyed on teaching confidence and content knowledge before and after the workshops. Follow-up surveys addressed teaching confidence and curricular implementation and were conducted 0.7 years after (all cohorts), 1.7 years after (2009 cohort), and 2.7 years after (2008 cohort). Teacher confidence (4-point scale: 1="not at all confident"; 4="very confident") on workshop content topics continued to rise in each subsequent survey from 2.7 (pre) to 3.3 (post) to 3.5 (0.7 yr follow up) to 3.7 (2-3 yr follow up) suggesting the program impact is long-lived. In the post-workshop surveys, 100% of participants agreed or strongly agreed that the program would positively impact their teaching. Average teacher performance on content questions improved

  4. K-12 students with concussions: a legal perspective. (United States)

    Zirkel, Perry A; Brown, Brenda Eagan


    This article provides a multipart analysis of the public schools' responsibility for students with concussions. The first part provides the prevailing diagnostic definitions of concussions and postconcussive syndrome. The second and central part provides (a) the legal framework of the two overlapping federal laws--the Individuals with Disabilities Education Act and Section 504 of the Rehabilitation Act and the varying state laws or local policies for individual health plans and (b) a summary of the developing body of hearing officer decisions, court decisions, and Office for Civil Rights rulings that have applied this framework to K-12 students with concussions. The final part offers recommendations for proactive return to school policies, with the school nurse playing a central supporting role. © The Author(s) 2014.

  5. How to Get Successfully Involved with K-12 Education (United States)

    Duncan, D.; Fraknoi, A.; Bennett, M.


    Many astronomers now have some involvement in K-12 education, either through their children, through large projects with an education or outreach office, or through an educational component to their own grants. Some may need to incorporate education components into future proposals. For those new to education, it can be difficult to decide how best to use their limited resources without "re-inventing the wheel." Some astronomers are comfortable taking a direct role in the classroom or working with teachers, others prefer developing web-based or printed materials, while still others wouldrather work with local schools of education to enhance the training of future teachers. Which of these roles is most useful? In this session, participants will learn what has worked well in the past, with special attention paid to ways in which astronomers' and physicists' training and instincts may fail them when working in education. Invited teachers will describe their classrooms and how astronomers can be most helpful to them. Sample (successful) activities will be demonstrated, and information given about the wide range of existing astronomy and space-science education programs around the country. A full menu of useful ways that astronomers can get involved will be presented, as well as the organizations and institutions which can help in devising a meaningful education program. Handouts will include a catalog of national astronomy education projects, a list of educational web sites, information about the NASA OSS education brokers and facilitators, examples of successful educational materials, and a listing of roles astronomers have played or could play to enhance K-12 education. Registration is required; see the AAS Education WWW page or email

  6. The Aloha Telescope for K-12 STEM Education (United States)

    Sowell, James R.


    How does one bring night-time astronomical observations into the classroom? How does a teacher - during the school day - show students the craters on the Moon, the rings of Saturn, or the four Galilean moons of Jupiter? One of the greatest drawbacks to teaching Astronomy is the lack of real-time telescopic observations during the school day, and yet this is a very exciting time for astronomical discoveries. The solution is to access a telescope in a substantially different time zone where it is still night. This facility - the Aloha Telescope - on Maui has already been established by a partnership between Georgia Tech and the Air Force Research Lab. This robotic telescope's sole purpose is for K-12 education, as it is equipped with a video-camera and is operated remotely via high-speed internet connections. This facility and its outreach program allow east-coast teachers and, in turn, students to have local daytime access to - and direct control of - the telescope. When observing the Moon, teachers and students will move the telescope wherever they wish across the highly-magnified lunar surface (~ 5 arcminute FOV). This telescope will enable night-time astronomical observations to come alive as day-time activities and will be an important tool for STEM education and activities. The use of the Aloha Telescope requires minimal training and is free after registering for a date and time.Dr. Sowell has written specific telescopic exercises and surface feature tours appropriate for K-12 and college-level users. These exercises, and other aspects of the Aloha Telescope and program, are posted on the website at

  7. Properties of putrescine uptake by PotFGHI and PuuP and their physiological significance in Escherichia coli. (United States)

    Terui, Yusuke; Saroj, Sunil D; Sakamoto, Akihiko; Yoshida, Taketo; Higashi, Kyohei; Kurihara, Shin; Suzuki, Hideyuki; Toida, Toshihiko; Kashiwagi, Keiko; Igarashi, Kazuei


    Properties of putrescine uptake by PotFGHI and PuuP and their physiological significance were studied using a polyamine biosynthesis and uptake deficient Escherichia coli KK3131 transformed with pACYC184 containing potFGHI or puuP. Putrescine uptake activity of E. coli KK3131 transformed with pACYC184-PotFGHI was higher than that of E. coli 3131 transformed with pACYC-PuuP when cells were cultured in the absence of putrescine. Putrescine uptake by PotFGHI was both ATP and membrane potential dependent, while that by PuuP was membrane potential dependent. Feedback inhibition by polyamines occurred at the PotFGHI uptake system but not at the PuuP uptake system. Expression of PuuP was reduced in the presence of PuuR, a negative regulator for PuuP, and expression of PuuR was positively regulated by glucose, which reduces the level of cAMP. The complex of cAMP and CRP (cAMP receptor protein) inhibited the expression of PuuR in the absence of glucose. Thus, the growth rate of E. coli KK3131 in the presence of both 0.4% (22.2 mM) glucose and 10 mM putrescine was in the order of cells transformed with pACYC-PotFGHI > pACYC-PuuP > pACYC-PuuP + PuuR, which was parallel with the polyamine content in cells. The results indicate that PotFGHI is necessary for rapid cell growth in the presence of glucose as an energy source. When glucose in medium was depleted, however, PuuP was absolutely necessary for cell growth in the presence of putrescine, because accumulation of putrescine to a high level by PuuP was necessary for utilization of putrescine as an energy source.

  8. Barriers in the Physics Pipeline from K-12 to Tenure (United States)

    Kilburn, Micha


    The lack of diversity in physics is a known problem, and yet efforts to change our demographics have only had minor effects during the last decade. I will explain some of the hidden barriers that dissuade underrepresented minorities in becoming physicists using a framework borrowed from sociology, Maslow's hierarchy of needs. I will draw from current research at the undergraduate to faculty levels over a variety of STEM fields that are also addressing a lack of diversity. I will also provide analysis from the Joint Institute for Nuclear Astrophysics Center for the Evolution of Elements (JINA-CEE) outreach programs to understand the likelihood of current K-12 students in becoming physicists. Specifically, I will present results from the pre-surveys from our Art 2 Science Camps (ages 8-14) about their attitudes towards science as well as results from analysis of teacher recommendations for our high school summer program. I will conclude with a positive outlook describing the pipeline created by JINA-CEE to retain students from middle school through college. This work was supported in part by the National Science Foundation under Grant No. PHY-1430152 (JINA Center for the Evolution of the Elements).

  9. "Flipping" educational technology professional development for K-12 educators (United States)

    Spencer, Daniel

    As the demand for more effective professional development increases in K-12 schools, trainers must adjust their training methods to meet the needs of their teacher learners. Just as lecture-heavy, teacher-centered instruction only meet the learning needs of a small minority of students, "sit and get" professional development rarely results in the teachers gaining the skills and confidence necessary to use technology effectively in their instruction. To resolve the frustrations of teachers related to ineffective professional development, a "Flipped PD" training model was developed based on the learning needs of adult learners, the integration of technological, pedagogical, and content knowledge (TPACK), learning activities, and the Flipped Classroom concept. Under this model, training shifts from a passive, trainer-centered format, to an active, learner-centered format where teachers learn to use technology in their classrooms by first focusing on pedagogical issues, then choosing the options that work best for addressing those issues in their unique situation, and completing "learn-by-doing" projects. Those who participate in "Flipped PD" style trainings tend to have more confidence upon completion that they can use the tools they were trained on in their teaching, as well as believe that the PD was engaging and a good use of their time.

  10. Students with Special Health Care Needs in K-12 Virtual Schools

    National Research Council Canada - National Science Library

    Heidi Fernandez; Richard E Ferdig; Lindsay A Thompson; Katherine Schottke; Erik W Black


      This study sought to establish a baseline for understanding the epidemiology of online K-12 students with special health care needs, determine the prevalence in K-12 online schooling of students...

  11. K-12 Education Nonprofit Employees' Perceptions of Strategies for Recruiting and Retaining Employees (United States)

    Byrne, Tara Marie


    This qualitative study explored the key reasons individuals who work in K-12 education nonprofit organizations enter the field of K-12 nonprofit education and their motivations for doing so. The purpose of this study was to find new strategies for recruiting and retaining K-12 education nonprofit employees by examining the obstacles that exist to…

  12. Interview with Joe Freidhoff: A Bird's-Eye View of K-12 Online Learning (United States)

    Pourreau, Leslie


    The intent of this article is to introduce long-time "Online Learning" readership to the field of K-12 online learning while also providing direction for the K-12 online learning scholars about where the field is going or should be going in terms of meeting the needs of K-12 stakeholders. Recently an interview was conducted with Dr. Joe…

  13. K-12 Teachers Encounter Digital Games: A Qualitative Investigation of Teachers' Perceptions of the Potential of Digital Games for K-12 Education (United States)

    Dickey, Michele D.


    The purpose of this study is to investigate teachers' perceptions of the integration of digital games for K-12 education. Specifically, this qualitative investigation focuses on reflective dialogued gathered from a group of K-12 educators about their experiences and perceptions of learning about and playing digital games for teaching and learning.…

  14. K-12 Phenology Lessons for the Phenocam Project (United States)

    Bennett, K. F.


    Phenology is defined as periodic [or annual] life cycles of plants and animals driven by seasonal environmental changes. Climate change impinges a strong effect on phenology, potentially altering the structure and functioning of ecosystems. In the fall of 2011, the Ashburnham-Westminster Regional School District became the first of five schools to join Harvard University's Phenocam Network with the installation of a webcam to monitor phenology (or 'phenocam') at Overlook Middle School in Ashburnham, Massachusetts. Our school district is now part of a network of near-surface remote sensing phenocams that capture and send images of forest, shrub, and grassland vegetation cover at more than 130 diverse sites in North America. Our phenocam provides a digital image every half hour of the mixed forest canopy north from the school, enabling the detection of changes in canopy development, quantified as canopy 'greenness'. As a part of the Phenocam project, students at the K-12 level have expanded the scope of phenological monitoring protocol that is part of the Harvard Forest Schoolyard Ecology Program, Buds, Leaves, and Global Warming. In this protocol, students work with ecologists at Harvard Forest to monitor buds and leaves on schoolyard trees to determine the length of the growing season, giving them the opportunity to be a part of real and important research concerning the critical environmental issue of climate change. Students involved in the Buds, Leaves, and Global Warming study have the opportunity to compare their ground data on budburst, color change, and leaf drop to the phenocam images, as well as to similar forested sites in locations throughout the United States. Lessons have been developed for comparing student data to phenocam images, canopy greenness time series graphs extracted from the images, and satellite data. Lessons addressing map scale and the Urban Heat Island effect will also be available for teachers. This project will greatly enhance the

  15. The gntP Gene of Escherichia coli Involved in Gluconate Uptake

    DEFF Research Database (Denmark)

    Klemm, Per; Tong, S.; Nielsen, Henrik


    The gntP gene, located between the fim and uxu loci in Escherichia coli K-12, has been cloned and characterized. Nucleotide sequencing of a region encompassing the gntP gene revealed an open reading frame of 447 codons with significant homology to the Bacillus subtilis gluconate permease. Northern...

  16. Regulatory mutants of the aroF-tyrA operon of Escherichia coli K-12. (United States)

    Cobbett, C S; Delbridge, M L


    The regulatory region of the aroF-tyrA operon was fused to the chloramphenicol acetyltransferase (cat) gene on a plasmid vector. Expression of the cat gene was subject to repression by tyrR+. This fusion was used to isolate regulatory mutants with increased expression of the cat gene in which repression by tyrR+ was affected. Nucleotide sequencing of these mutants has led to the identification of three sites involved in the repression of aroF by tyrR+. The existence of a functional promoter divergently transcribing from the aroF regulatory region was also demonstrated by using the cat fusion vector. The expression of this promoter is also regulated by tyrR+.

  17. Cool Science: K-12 Climate Change Art Displayed on Buses (United States)

    Chen, R. F.; Lustick, D. S.; Lohmeier, J.; Thompson, S. R.


    Cool science is an art contest where K12 students create placards (7" x 22") to educate the public about climate change. Students are prompted to create their artwork in response to questions such as: What is the evidence for climate change? How does climate change impact your local community? What can you do to reduce the impacts of climate change? In each of three years, 500-600 student entrees have been submitted from more than 12 school districts across Massachusetts. A panel of judges including scientists, artists, rapid transit representatives, and educators chooses elementary, middle, and high school winners. Winners (6), runners-up (6), and honorable mentions (12) and their families and teachers are invited to an annual Cool Science Award Ceremony to be recognized and view winning artwork. All winning artwork is posted on the Cool Science website. The winning artwork (2 per grade band) is converted into placards (11" x 28") and posters (2.5' x 12') that are placed on the inside (placards) and outside (posters) of buses. Posters are displayed for one month. So far, Cool Science was implemented in Lowell, MA where over 5000 public viewers see the posters daily on the sides of Lowell Rapid Transit Authority (LRTA) buses, making approximately 1,000,000 impressions per year. Cool Science acts to increase climate literacy in children as well as the public, and as such promotes intergenerational learning. Using art in conjunction with science learning about climate change appears to be effective at engaging not just traditionally high achieving science students, but also those interested in the creative arts. Hearing winners' stories about how they created their artwork and what this contest meant to them supports the idea that Cool Science attracts a wide diversity of students. Parents discuss climate change with their children. Multiple press releases announcing the winners further promotes the awareness of climate change throughout school districts and their

  18. Use of Streptococcus salivarius K12 in the prevention of streptococcal and viral pharyngotonsillitis in children. (United States)

    Di Pierro, Francesco; Colombo, Maria; Zanvit, Alberto; Risso, Paolo; Rottoli, Amilcare S


    Streptococcus salivarius K12 is an oral probiotic strain releasing two lantibiotics (salivaricin A2 and salivaricin B) that antagonize the growth of S. pyogenes, the most important bacterial cause of pharyngeal infections in humans also affected by episodes of acute otitis media. S. salivarius K12 successfully colonizes the oral cavity, and is endowed with an excellent safety profile. We tested its preventive role in reducing the incidence of both streptococcal and viral pharyngitis and/or tonsillitis in children. We enrolled 61 children with a diagnosis of recurrent oral streptococcal disorders. Thirty-one of them were enrolled to be treated daily for 90 days with a slow-release tablet for oral use, containing no less than 1 billion colony-forming units/tablet of S. salivarius K12 (Bactoblis®), and the remaining 30 served as the untreated control group. During treatment, they were all examined for streptococcal infection. Twenty children (ten per group) were also assessed in terms of viral infection. Secondary end points in both groups were the number of days under antibiotic and antipyretic therapy and the number of days off school (children) and off work (parents). The 30 children who completed the 90-day trial with Bactoblis® showed a significant reduction in their episodes of streptococcal pharyngeal infection (>90%), as calculated by comparing the infection rates of the previous year. No difference was observed in the control group. The treated group showed a significant decrease in the incidence (80%) of oral viral infections. Again, there was no difference in the control group. With regard to secondary end points, the number of days under antibiotic treatment of the treated and control groups were 30 and 900 respectively, days under antipyretic treatment 16 and 228, days of absence from school 16 and 228, and days of absence from work 16 and 228. The product was well tolerated by the subjects, with no side effects, and only one individual reported bad

  19. K-12 Neuroscience Education Outreach Program: Interactive Activities for Educating Students about Neuroscience (United States)

    Deal, Alex L.; Erickson, Kristen J.; Bilsky, Edward J.; Hillman, Susan J.; Burman, Michael A.


    The University of New England’s Center for Excellence in the Neurosciences has developed a successful and growing K-12 outreach program that incorporates undergraduate and graduate/professional students. The program has several goals, including raising awareness about fundamental issues in neuroscience, supplementing science education in area schools and enhancing undergraduate and graduate/professional students’ academic knowledge and skill set. The outreach curriculum is centered on core neuroscience themes including: Brain Safety, Neuroanatomy, Drugs of Abuse and Addiction, Neurological and Psychiatric Disorders, and Cognition and Brain Function. For each theme, lesson plans were developed based upon interactive, small-group activities. Additionally, we’ve organized our themes in a “Grow-up, Grow-out” approach. Grow-up refers to returning to a common theme, increasing in complexity as we revisit students from early elementary through high school. Grow-out refers to integrating other scientific fields into our lessons, such as the chemistry of addiction, the physics of brain injury and neuronal imaging. One of the more successful components of our program is our innovative team-based model of curriculum design. By creating a team of undergraduate, graduate/professional students and faculty, we create a unique multi-level mentoring opportunity that appears to be successful in enhancing undergraduate students’ skills and knowledge. Preliminary assessments suggest that undergraduates believe they are enhancing their content knowledge and professional skills through our program. Additionally, we’re having a significant, short-term impact on K-12 interest in science. Overall, our program appears to be enhancing the academic experience of our undergraduates and exciting K-12 students about the brain and science in general. PMID:25565921

  20. K-12 Neuroscience Education Outreach Program: Interactive Activities for Educating Students about Neuroscience. (United States)

    Deal, Alex L; Erickson, Kristen J; Bilsky, Edward J; Hillman, Susan J; Burman, Michael A


    The University of New England's Center for Excellence in the Neurosciences has developed a successful and growing K-12 outreach program that incorporates undergraduate and graduate/professional students. The program has several goals, including raising awareness about fundamental issues in neuroscience, supplementing science education in area schools and enhancing undergraduate and graduate/professional students' academic knowledge and skill set. The outreach curriculum is centered on core neuroscience themes including: Brain Safety, Neuroanatomy, Drugs of Abuse and Addiction, Neurological and Psychiatric Disorders, and Cognition and Brain Function. For each theme, lesson plans were developed based upon interactive, small-group activities. Additionally, we've organized our themes in a "Grow-up, Grow-out" approach. Grow-up refers to returning to a common theme, increasing in complexity as we revisit students from early elementary through high school. Grow-out refers to integrating other scientific fields into our lessons, such as the chemistry of addiction, the physics of brain injury and neuronal imaging. One of the more successful components of our program is our innovative team-based model of curriculum design. By creating a team of undergraduate, graduate/professional students and faculty, we create a unique multi-level mentoring opportunity that appears to be successful in enhancing undergraduate students' skills and knowledge. Preliminary assessments suggest that undergraduates believe they are enhancing their content knowledge and professional skills through our program. Additionally, we're having a significant, short-term impact on K-12 interest in science. Overall, our program appears to be enhancing the academic experience of our undergraduates and exciting K-12 students about the brain and science in general.

  1. Participative Teaching with Mobile Devices and Social Networks for K-12 Children

    Directory of Open Access Journals (Sweden)

    Livia Stefan


    Full Text Available This article details a set of participatory pedagogical experiments conducted within a research grant PN II IDEI (”Time Maps. Real communities, virtual worlds, experimented pasts” performed with the purpose of helping rural communities in identifying their cultural heritage andtransmitting it to the younger generations by means of modern IT technologies, including web 2.0. In a Danubian rural community, several points of archaeological interest (POIs were identified, which were then included in a geographic Augmented Reality application for smartphones and tablets. Subsequently, the geographic data were collected from the archaeological site by the K-12 children, under the coordination of an academic staff member of the National University of Arts in Bucharest, and stored on their devices using Google Maps. The augmented information provided onthe site was annotated and shared with other K-12 children, through different social networks sites (SNS and content postings. This first stage experiment was extended to the development of a social learning environment complementary to the educational site ( to support thetransmission of several traditional technologies (textile, ceramic, glass in a collaborative manner. We consider that our experiments can significantly increase the visibility of the information pertaining to the identity of target places and communities among the younger generation. A mobile-learning paradigm, in combination with web 2.0 technologies, was the support for a distributed and low-cost platform for communication and collaboration. Social networks linked thearchaeological heritage and the academic research with the larger community of rural K-12 children. The article analyzes this platform as a solution for creating, collecting and sharingeducational content, and presents conclusions on using social media for effective blended learning and transmittal of the cultural heritage.

  2. Sense and Sensibility: The Case for the Nationwide Inclusion of Engineering in the K-12 Curriculum (United States)

    Lindberg, Robert E.; Pinelli, Thomas E.; Batterson, James G.


    The competitive status of the United States is inextricably linked to innovation just as innovation is inseparable from science, technology, engineering, and mathematics. To stay competitive in innovation requires that the United States produce a 21st century workforce complete with requisite education, training, skills, and motivation. If we accept a priori that science, technology, engineering, and mathematics education are crucial to competitiveness and innovation and that, in terms of innovation, mathematics, science, and engineering are interdependent, why are mathematics and science uniformly ubiquitous in the K-12 curriculum while engineering is conspicuously absent? We are passionate in our belief that the uniform addition of engineering to the K-12 curriculum will help ensure that the nation has "the right" 21st Century workforce. Furthermore, we believe that a nationwide effort, led by a coalition of engineering academics, practitioners, and societies is required to turn this goal into reality. However, accomplishing this goal necessitates, as we are reminded by the title of Jane Austen's timeless novel, "Sense and Sensibility", a workable solution that seeks the "middle ground" between passion and reason. We begin our paper by making two essential points: Engineers are not scientists. Engineering exists separate from science, has its own specialized knowledge community apart from science, and it is largely responsible for many of the most significant advancements and improvements in the quality of our life. Our workable solution requires that K-12 education, nationwide, accommodate the inclusion of engineering as a stand alone curriculum and we offer three reasons to support our position: (1) workforce development, (2) stimulating interest in STEM (science, technology, engineering, and mathematics) courses and careers, and (3) creating a technologically literate society. We conclude with some thoughts on how this important goal can be accomplished.

  3. Positive clinical outcomes derived from using Streptococcus salivarius K12 to prevent streptococcal pharyngotonsillitis in children: a pilot investigation. (United States)

    Di Pierro, Francesco; Colombo, Maria; Zanvit, Alberto; Rottoli, Amilcare S


    Streptococcus salivarius K12 (BLIS K12®) is a probiotic strain producing the bacteriocins salivaricin A2 and salivaricin B, both of which strongly antagonize the growth of Streptococcus pyogenes, the most important bacterial cause of pharyngeal infections in humans. It successfully colonizes and exhibits persistence in the oral cavity and is endowed with an excellent safety profile. Previous observations of a small group of children indicated that the use of BLIS K12 could also reduce the occurrence of viral pharyngitis. The present study focused on a further evaluation of the role of BLIS K12 in the control of pediatric streptococcal disease and moreover whether its use could also help provide protection against various nonstreptococcal infections. In total, 48 children with a recent history of recurrent pharyngeal streptococcal disease were enrolled in the treated group. The control group comprised 76 children known to have had a very low recent occurrence of oral streptococcal disease. The treated children were given BLIS K12 daily for 90 days. The number of episodes of streptococcal pharyngotonsillitis, tracheitis, viral pharyngitis, rhinitis, flu, laryngitis, acute otitis media, enteritis, and stomatitis was recorded during probiotic treatment and for a follow-up period of 9 months, and this was compared with the episodes of the control group over the corresponding period. Compared with the pretreatment time period, 2013, a 90% reduction of streptococcal pharyngeal disease was observed in 2014; compared with untreated children, a statistically significant reduction of all of the other disease conditions assessed, other than stomatitis, was detected in the probiotic-treated children. In agreement with previous findings, in the present study, it was found that the daily use of BLIS K12 has been associated with a concurrent and persisting reduction in the occurrence of pharyngeal, recurrent, streptococcal disease. Moreover, the benefits to children may also

  4. The Next Generation Science Standards: An Historic Opportunity for K-12 Earth and Space Science Education (United States)

    Johnson, R. M.; Passow, M. J.; Holzer, M. A.; Moore, J.


    The Next Generation Science Standards (NGSS) provide an historic opportunity to significantly improve Earth and space science (ESS) education nationally at the K-12 level. The increased emphasis on ESS related topics in the NGSS relative to previous standards provides a real opportunity for ensuring all K-12 students in adopting states learn about the ESS - allowing us to reach many more students than are currently are exposed to our discipline. The new standards are also exciting in that they explicitly couple science and engineering practice, cross-cutting concepts, and disciplinary core ideas in such a way that student must actively demonstrate their understanding through actions rather than through mere regurgitation of memorized responses. Achieving mastery of NGSS Performance Expectations will require practice with higher-order learning skills - with students engaging in the practices of scientists and engineers. Preparing students for this mastery will be a challenging task for teachers, since in many states professional development support is limited at best for the current curriculum - let alone the curricula that will be developed to address the NGSS. As adoption of the NGSS expands across the country, states will be at various levels of implementation of the new standards over the next several years - and there is real concern that teachers must have sufficient professional development to be able to be successful in preparing their students - particularly in view of likely coupled assessments and teacher evaluations. NESTA strongly supports implementation of the NGSS, and the rigorous and compelling ESS education it will engender, when coupled with a strong emphasis nationwide on teacher professional development. For the past two years, the National Earth Science Teachers Association (NESTA) has continued our leadership in K-12 ESS education through workshops, web seminars, events and publications that emphasize implementation of the NGSS in ESS

  5. A Meta-Analysis of Self-Monitoring on Reading Performance of K-12 Students. (United States)

    Guzman, Guadalupe; Goldberg, Taryn S; Swanson, H Lee


    The published single-case design (SCD) research (N = 19 articles) on self-monitoring and reading performance was synthesized. The following inclusion criteria were used: (a) the study must have been peer-reviewed, (b) implemented an intervention targeting student self-monitoring of reading skills, (c) included data on at least 1 reading outcome, (d) included visual representation of the data, and (f) the study must have used an SCD to assess the topic of interest. A total of 67 participants, 45 males and 22 females, ranging in age from 7:8 -18:7 were included in the current meta-analysis. Ethnicity was reported for 42 students: 23 were Caucasian, 12 were African American, and 7 were Latino/Hispanic. Studies were compared with those meeting What Works Clearinghouse (WWC) standards and those not meeting standards. The Tau-U effect size (ES) method was the main calculation method used; however, Phi ES estimates are included for comparison purposes. Results indicated that self-monitoring had an overall significant large positive effect on the reading performance of K-12 students, Tau-U = 0.79, 95% confidence interval (CI) [0.64, 0.93], p reading intervention for students in Grades K-12. Furthermore, findings indicate that larger ES values were identified when consolidating studies based on WWC guidelines as compared with consolidating across all studies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  6. Clinical significance and phylogenetic background of extended spectrum β-lactamase producing Escherichia coli isolates from extra-intestinal infections. (United States)

    Chakraborty, Arindam; Adhikari, Prabha; Shenoy, Shalini; Saralaya, Vishwas


    Escherichia coli producing extended spectrum-β-lactamases (ESBL), particularly CTX-M type ESBLs, have rapidly spread worldwide and pose a serious threat for healthcare-associated infections. We performed a molecular detection and characterization study of ESBL-related bla genes, including blaTEM, blaSHV, blaCTX-M, and blaCTX-M15, and also assessed the relationship between the phylogenetic background of strains carrying ESBL genes and the patient's clinical outcome. A total of 300 non-repeated, clinically significant isolates were investigated. The molecular types of ESBL genes were determined using multiplex PCR. Phylogenetic analysis was performed using triplex PCR methods. Antibiograms and the patient's clinical outcome were collected in a structured pro forma. Among the 300 isolates, 212 (70.5%) isolates were found to carry ESBL genes. A total of 186 (62%) strains were positive for the blaCTX-M gene, and 171 isolates (approximately 92%) of these blaCTX-M producers were positive for blaCTXM-15. Phylogenetic analysis of the isolates indicated that 41 (67%) Group A, 22 (81.50%) group B1, 67 (64.5%) group B2 and 82 (76%) group D isolates carried different ESBL genes. Appropriate antibiotic therapy helped to resolve infection in 66.5% patients. Our study documented the high prevalence of ESBLs in E. coli isolates, with CTX-M-15 as the predominant ESBL gene in the region, and these isolates predominantly belonged to commensal phylo-groups. Thus, an appropriate antibiotic and hospital policy is required to reduce the horizontal spread of ESBL genes among various bacterial strains, whereas in the near future, the spread of ESBL producers may result in therapeutic dead ends. Copyright © 2014 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

  7. Research and Practice in K-12 Online Learning: A Review of Open Access Literature

    Directory of Open Access Journals (Sweden)

    Cathy S. Cavanaugh


    Full Text Available The literature related to online learning programs for K-12 students dates to the mid-1990s and builds upon a century of research and practice from K-12 distance education. While K-12 online learning programs have evolved and grown over the past decade, the amount of published research on virtual schooling practice and policy is limited. The current literature includes practitioner reports and experimental and quasi-experimental studies, both published and unpublished. This paper reviews open access literature in K-12 online learning and reports on a structured content analysis of the documents. Themes in the literature include steady growth and a focus on the benefits, challenges, and broad effectiveness of K-12 online learning. In addition, newly developed standards for K-12 online learning are emerging in descriptions of effective practices.

  8. Content Management on the Internet: A look at K-12 schools access to resources


    Wenrich, John Richard


    The Internet presents a new phenomenon to educators and students in the K-12 environment. It's ease of use and ready access to material provides an overwhelming resource for use in the K-12 classroom. This study looked at content management of Internet resources in the K-12 school environment. Content management is defined as the methods of organizing access to the information available on the Internet allowing the teacher to effectively use resources in a classroom setting. Teachers have man...

  9. Fostering K-12 Inquiry-based Lesson Development on Regional Water Resource Issues in Los Angeles Urban Schools through the NSF UCLA SEE-LA GK-12 program (United States)

    Hogue, T. S.; Burke, M. P.; Thulsirag, V.; Daniel, J.; Moldwin, M.; Nonacs, P.


    A National Science Foundation Graduate Teaching Fellows in K- 12 Education program at UCLA (SEE-LA; ) partners UCLA faculty and graduate students (fellows) with urban middle and high school science teachers and their students to foster programs of science and engineering exploration that bring the environment of Los Angeles into the classroom. UCLA graduate fellows serve as scientists-in-residence at four partner schools to integrate inquiry-based science lessons, facilitate advancements in science content teaching, and ultimately, to improve their own science communication skills. As part of their fellowship, graduate students are required to develop inquiry-based lessons in their partner classroom. During the first two years of the project, the SEE-LA fellows have developed a range of inquiry-based activities, from invertebrate observations in an urban stream system, to water and home energy consumption surveys, to a school biodiversity investigation, to a school-wide alternative energy fair, to engineering the cleanup of environmental disasters, such as the recent oil spill in the Gulf of Mexico. Several of the current fellows have dissertation research in water resource related fields and are specifically integrating lessons specific to their research into their partner classrooms, including urban stream water quality, post-fire watershed behavior, beach water quality assessment and E. coli source tracking. This presentation will provide an overview of goals of the SEE-LA GK-12 program, development of inquiry-based water resource lessons and resulting engagement in the partner classrooms. University and local pre-college school partnerships provide an excellent opportunity to support the development of graduate student communication and teaching skills while also contributing significantly to the integration of science education into K-12 curriculum.

  10. New Learning Models: The Evolution of Online Learning into Innovative K-12 Blended Programs (United States)

    Patrick, Susan


    The author traces the growth of K-12 online learning in the United States from its modest genesis in the mid-1990s with 50,000 students to the more than 4 million enrollments today, the fastest scaling ever of any innovation in K-12 education. The evolution from one-size-fits-all online courses to innovative, blended instructional models that are…

  11. Virtual Schools: The Changing Landscape of K-12 Education in the U.S. (United States)

    Toppin, Ian N.; Toppin, Sheila M.


    Virtual schools are a growing phenomenon in k-12 education. School systems in almost every state in the United States offer some version of fully online or blended education. It is no longer far-fetched to conclude that if the current trend continues, virtual school enrollments will eclipse those of traditional brick-and-mortar k-12 institutions…

  12. STEM Integration in K-12 Education: Status, Prospects, and an Agenda for Research (United States)

    Honey, Margaret; Pearson, Greg; Schweingruber, Heidi


    "STEM Integration in K-12 Education" examines current efforts to connect the STEM disciplines in K-12 education. This report identifies and characterizes existing approaches to integrated STEM education, both in formal and after- and out-of-school settings. The report reviews the evidence for the impact of integrated approaches on…

  13. K-12 Teacher Perceptions Regarding the Flipped Classroom Model for Teaching and Learning (United States)

    Gough, Evan; DeJong, David; Grundmeyer, Trent; Baron, Mark


    A great deal of evidence can be cited from higher education literature on the effectiveness of the flipped classroom; however, very little research was discovered on the flipped classroom at the K-12 level. This study examined K-12 teachers' perceptions regarding the flipped classroom and differences in teachers' perceptions based on grade level…

  14. Changes in K-12 Education: Implications for the BC Post-Secondary System (United States)

    McQuarrie, Fiona A. E.


    It is generally assumed by educators that the K-12 curriculum--the curriculum used in primary, elementary, and secondary education--will affect students' post-secondary educational experiences and their ability to enter the workforce. This report takes a multi-faceted approach to addressing the impact of changes in the K-12 curriculum on students'…

  15. Exploring Arizona K-12 Virtual Educator Experiences and Perspectives Developing Collaborative Learning Communities (United States)

    Cross, Deborah Iyron


    Arizona Online Instruction (AOI) provided an instructional alternative to nearly fifty thousand K-12 students in Arizona during the 2012-2013 school year. Growth in online education underscores the importance of evolving the role of the K-12 virtual teacher as the human agent (Turvey, 2008) demonstrating social learning theory (Bandura, 1977) by…

  16. Physical Education Teacher Educator's Perceptions toward and Understanding of K-12 Online Physical Education (United States)

    Daum, David N.; Woods, Amelia M.


    K-12 online physical education (OLPE) is as an educational opportunity in at least 30 states in the US (NASPE, 2006; 2010; 2012). The purpose of this study was to examine physical education teacher educators' perceptions toward and understanding of K-12 OLPE. Bandura's Social Cognitive Theory (1986) served as the theoretical framework for this…

  17. An Exploratory Study on K-12 Teachers' Use of Technology and Multimedia in the Classroom (United States)

    Martin, Florence; Carr, Marsha L.


    21st century has seen new technology and multimedia made available for integration in K-12 classrooms. This exploratory study examines K-12 teachers' use of technology and multimedia in the classroom in two southern counties in the Southeastern United States. The purpose of the study was to answer the following five research questions: 1) What…

  18. State P-20 Councils and Collaboration between K-12 and Higher Education (United States)

    Rippner, Jennifer A.


    For decades, numerous observers have agreed on the value of collaboration between K-12 and higher education--especially as these sectors work toward increasing college readiness and success. While most states maintain separate agencies for K-12 and higher education, many states have worked to foster collaboration through state P-20 councils.…

  19. Development and Evaluation of Food Safety Modules for K-12 Science Education (United States)

    Chapin, Travis K.; Pfuntner, Rachel C.; Stasiewicz, Matthew J.; Wiedmann, Martin; Orta-Ramirez, Alicia


    Career and educational opportunities in food science and food safety are underrecognized by K-12 students and educators. Additionally, misperceptions regarding nature of science understanding persist in K-12 students despite being emphasized as an important component of science education for over 100 y. In an effort to increase awareness…

  20. From Teacher to Teacher Educator: Should You Move from a K-12 Classroom into Higher Education? (United States)

    Clement, Mary C.


    College teaching can be as rewarding as a K-12 career and, whether in elementary school or college, students deserve good teachers. College professors who prepare teachers can have a tremendous impact on K-12 classrooms for decades into the future. However, career paths vary widely, and the path to teaching in higher education is as unique as the…

  1. Value Added Models and the Implementation of the National Standards of K-12 Physical Education (United States)

    Seymour, Clancy M.; Garrison, Mark J.


    The implementation of value-added models of teacher evaluation continue to expand in public education, but the effects of using student test scores to evaluate K-12 physical educators necessitates further discussion. Using the five National Standards for K-12 Physical Education from the Society of Health and Physical Educators America (SHAPE),…

  2. Development of an Attitude Scale to Assess K-12 Teachers' Attitudes toward Nanotechnology (United States)

    Lan, Yu-Ling


    To maximize the contributions of nanotechnology to this society, at least 60 countries have put efforts into this field. In Taiwan, a government-funded K-12 Nanotechnology Programme was established to train K-12 teachers with adequate nanotechnology literacy to foster the next generation of Taiwanese people with sufficient knowledge in…

  3. Code to Learn: Where Does It Belong in the K-12 Curriculum?

    Directory of Open Access Journals (Sweden)

    Jesús Moreno León


    Full Text Available The introduction of computer programming in K-12 has become mainstream in the last years, as countries around the world are making coding part of their curriculum. Nevertheless, there is a lack of empirical studies that investigate how learning to program at an early age affects other school subjects. In this regard, this paper compares three quasi-experimental research designs conducted in three different schools (n=129 students from 2nd and 6th grade, in order to assess the impact of introducing programming with Scratch at different stages and in several subjects. While both 6th grade experimental groups working with coding activities showed a statistically significant improvement in terms of academic performance, this was not the case in the 2nd grade classroom. Notable disparity was also found regarding the subject in which the programming activities were included, as in social studies the effect size was double that in mathematics.

  4. Development of the Advanced Energy Design Guide for K-12 Schools -- 50% Energy Savings

    Energy Technology Data Exchange (ETDEWEB)

    Bonnema, E.; Leach, M.; Pless, S.; Torcellini, P.


    This Technical Support Document (TSD) describes the process and methodology for the development of the Advanced Energy Design Guide for K-12 School Buildings: Achieving 50% Energy Savings Toward a Net Zero Energy Building (AEDG-K12) (ASHRAE et al. 2011a). The AEDG-K12 provides recommendations for achieving 50% whole-building energy savings in K-12 schools over levels achieved by following ANSI/ASHRAE/IESNA Standard 90.1-2004, Energy Standard for Buildings Except Low-Rise Residential Buildings (Standard 90.1-2004) (ASHRAE 2004b). The AEDG-K12 was developed in collaboration with the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), the American Institute of Architects (AIA), the Illuminating Engineering Society of North America (IES), the U.S. Green Building Council (USGBC), and the U.S. Department of Energy (DOE).

  5. Climate Change Education Today in K-12: What's Happening in the Earth and Space Science Classroom? (United States)

    Holzer, M. A.; National Earth Science Teachers Association


    Climate change is a highly interdisciplinary topic, involving not only multiple fields of science, but also social science and the humanities. There are many aspects of climate change science that make it particularly well-suited for exploration in the K-12 setting, including opportunities to explore the unifying processes of science such as complex systems, models, observations, change and evolution. Furthermore, this field of science offers the opportunity to observe the nature of science in action - including how scientists develop and improve their understanding through research and debate. Finally, climate change is inherently highly relevant to students - indeed, students today will need to deal with the consequences of the climate change. The science of climate change is clearly present in current science education standards, both at the National level as well as in the majority of states. Nonetheless, a significant number of teachers across the country report difficulties addressing climate change in the classroom. The National Earth Science Teachers Association has conducted several surveys of Earth and space science educators across the country over the past several years on a number of issues, including their needs and concerns, including their experience of external influences on what they teach. While the number of teachers that report external pressures to not teach climate change science are in the minority (and less than the pressure to not teach evolution and related topics), our results suggest that this pressure against climate change science in the K-12 classroom has grown over the past several years. Some teachers report being threatened by parents, being encouraged by administrators to not teach the subject, and a belief that the "two sides" of climate change should be taught. Survey results indicate that teachers in religious or politically-conservative districts are more likely to report difficulties in teaching about climate change than in

  6. The Role of Extension Specialists in Meeting K-12 Science Education Goals. (United States)

    Milam, Michael R.


    Describes a variety of ways in which extension specialists can support and supplement the K-12 science curriculum in Missouri. Includes a description of the Missouri Mastery Achievement Test (MMAT) and its use in assessing agricultural literacy. (DDR)

  7. Fostering Transformative Learning in an Online ESL Professional Development Program for K-12 Teachers

    National Research Council Canada - National Science Library

    Karin Sprow Forte; David Blouin


      This qualitative study examines evidence of transformative learning surrounding sociocultural issues in the K-12 classroom of in-service teachers, while participating in an online English as a Second Language (ESL...

  8. K12 Education Program Lessons Learned at the Center for Earthquake Research and Information (United States)

    Patterson, G. L.; Dry, M.


    The Center for Earthquake Research and Information at the University of Memphis has been committed to increasing awareness for Seismic Hazard, Earthquake Engineering, and Earth Science among Mid-America's policy-makers, engineers, emergency managers, the general public, and K-12 teachers and students for nearly three decades. During that time we have learned many lessons related to providing effective education and outreach programs, especially for K-12 students. The lessons learned from these activities may be particularly appropriate for other regions where large earthquakes occur infrequently but have disproportionately high consequence areas due to low attenuation of seismic waves. Effective education programs in these settings must provide a consistent message across many states to a wide variety of socio-economic groups and professional communities through the leveraged resources of various groups and agencies. It is also beneficial to hire and train staff with K-12 teaching experience to work directly K-12 education organizations, and science curriculum coordinators.

  9. Engaging Scientists in NASA Education and Public Outreach: K - 12 Formal Education (United States)

    Bartolone, Lindsay; Smith, D. A.; Eisenhamer, B.; Lawton, B. L.; Universe Professional Development Collaborative, Multiwavelength; NASA Data Collaborative, Use of; SEPOF K-12 Formal Education Working Group; E/PO Community, SMD


    The NASA Science Education and Public Outreach Forums support the NASA Science Mission Directorate (SMD) and its education and public outreach (E/PO) community through a coordinated effort to enhance the coherence and efficiency of SMD-funded E/PO programs. The Forums foster collaboration between scientists with content expertise and educators with pedagogy expertise. We present opportunities for the astronomy community to participate in collaborations supporting the NASA SMD efforts in the K - 12 Formal Education community. Members of the K - 12 Formal Education community include classroom educators, homeschool educators, students, and curriculum developers. The Forums’ efforts for the K - 12 Formal Education community include a literature review, appraisal of educators’ needs, coordination of audience-based NASA resources and opportunities, professional development, and support with the Next Generation Science Standards. Learn how to join in our collaborative efforts to support the K - 12 Formal Education community based upon mutual needs and interests.

  10. Zero Energy Schools: Designing for the Future: Zero Energy Ready K-12 Schools

    Energy Technology Data Exchange (ETDEWEB)

    Torcellini, Paul A [National Renewable Energy Laboratory (NREL), Golden, CO (United States)


    Designing, building, and operating zero energy ready K-12 schools provides benefits for districts, students, and teachers. Optimizing energy efficiency is important in any building, but it's particularly important in K-12 schools. Many U.S. school districts struggle for funding, and improving a school building's energy efficiency can free up operational funds that may then be available for educational and other purposes.

  11. Development of an Attitude Scale to Assess K-12 Teachers' Attitudes toward Nanotechnology (United States)

    Lan, Yu-Ling


    To maximize the contributions of nanotechnology to this society, at least 60 countries have put efforts into this field. In Taiwan, a government-funded K-12 Nanotechnology Programme was established to train K-12 teachers with adequate nanotechnology literacy to foster the next generation of Taiwanese people with sufficient knowledge in nanotechnology. In the present study, the Nanotechnology Attitude Scale for K-12 teachers (NAS-T) was developed to assess K-12 teachers' attitudes toward nanotechnology. The NAS-T included 23 Likert-scale items that can be grouped into three components: importance of nanotechnology, affective tendencies in science teaching, and behavioural tendencies to teach nanotechnology. A sample of 233 K-12 teachers who have participated in the K-12 Nanotechnology Programme was included in the present study to investigate the psychometric properties of the NAS-T. The exploratory factor analysis of this teacher sample suggested that the NAS-T was a three-factor model that explained 64.11% of the total variances. This model was also confirmed by the confirmatory factor analysis to validate the factor structure of the NAS-T. The Cronbach's alpha values of three NAS-T subscales ranged from 0.89 to 0.95. Moderate to strong correlations among teachers' NAS-T domain scores, self-perception of own nanoscience knowledge, and their science-teaching efficacy demonstrated good convergent validity of the NAS-T. As a whole, psychometric properties of the NAS-T indicated that this instrument is an effective instrument for assessing K-12 teachers' attitudes toward nanotechnology. The NAS-T will serve as a valuable tool to evaluate teachers' attitude changes after participating in the K-12 Nanotechnology Programme.

  12. Significant rewiring of the transcriptome and proteome of an Escherichia coli strain harboring a tailored exogenous global regulator IrrE.

    Directory of Open Access Journals (Sweden)

    Tingjian Chen

    Full Text Available Cell reprogramming for microorganisms via engineered or artificial transcription factors and RNA polymerase mutants has presented a powerful tool for eliciting complex traits that are practically useful particularly for industrial strains, and for understanding at the global level the regulatory network of gene transcription. We previously further showed that an exogenous global regulator IrrE (derived from the extreme radiation-resistant bacterium Deinococcus radiodurans can be tailored to confer Escherichia coli (E. coli with significantly enhanced tolerances to different stresses. In this work, based on comparative transcriptomic and proteomic analyses of the representative strains E1 and E0, harboring the ethanol-tolerant IrrE mutant E1 and the ethanol-intolerant wild type IrrE, respectively, we found that the transcriptome and proteome of E. coli were extensively rewired by the tailored IrrE protein. Overall, 1196 genes (or approximately 27% of E. coli genes were significantly altered at the transcriptomic level, including notably genes in the nitrate-nitrite-nitric oxide (NO pathway, and genes for non-coding RNAs. The proteomic profile revealed significant up- or downregulation of several proteins associated with syntheses of the cell membrane and cell wall. Analyses of the intracellular NO level and cell growth under reduced temperature supported a close correlation between NO and ethanol tolerance, and also suggests a role for membrane fluidity. The significantly different omic profiles of strain E1 indicate that IrrE functions as a global regulator in E. coli, and that IrrE may be evolved for other cellular tolerances. In this sense, it will provide synthetic biology with a practical and evolvable regulatory "part" that operates at a higher level of complexity than local regulators. This work also suggests a possibility of introducing and engineering other exogenous global regulators to rewire the genomes of microorganism cells.

  13. Cryomilling-induced solid dispersion of poor glass forming/poorly water-soluble mefenamic acid with polyvinylpyrrolidone K12. (United States)

    Kang, Naewon; Lee, Jangmi; Choi, Ji Na; Mao, Chen; Lee, Eun Hee


    The effect of mechanical impact on the polymorphic transformation of mefenamic acid (MFA) and the formation of a solid dispersion of mefenamic acid, a poor glass forming/poorly-water soluble compound, with polyvinylpyrrolidone (PVP) K12 was investigated. The implication of solid dispersion formation on solubility enhancement of MFA, prepared by cryomilling, was investigated. Solid state characterization was conducted using powder X-ray diffraction (PXRD) and Fourier-transform infrared (FTIR) spectroscopy combined with crystal structure analysis. Apparent solubility of the mixtures in pH 7.4 buffer was measured. A calculation to compare the powder patterns and FTIR spectra of solid dispersions with the corresponding physical mixtures was conducted. Solid state characterization showed that (1) MFA I transformed to MFA II when pure MFA I was cryogenically milled (CM); and (2) MFA forms a solid dispersion when MFA was cryogenically milled with PVP K12. FTIR spectral analysis showed that hydrogen bonding facilitated by mechanical impact played a major role in forming solid dispersions. The apparent solubility of MFA was significantly improved by making a solid dispersion with PVP K12 via cryomilling. This study highlights the importance of cryomilling with a good hydrogen bond forming excipient as a technique to prepare solid dispersion, especially when a compound shows a poor glass forming ability and therefore, is not easy to form amorphous forms by conventional method.

  14. A randomized trial of ACT bibliotherapy on the mental health of K-12 teachers and staff. (United States)

    Jeffcoat, Tami; Hayes, Steven C


    The mental health challenges of some vocations present a challenge for current intervention models. Bibliotherapy focused on transdiagnostic processes that might both prevent and alleviate a range of mental health distress could be an effective and practical approach. K-12 school personnel (N = 236; 91% female; 30-60 years old) responding to a wellness-oriented program announcement were randomized to receive an Acceptance and Commitment Therapy (ACT) self-help volume or to a waitlist. Three-fourths were above clinical cutoffs in general mental health, depression, anxiety, or stress. Participants read the book for two months, completed exercises and quizzes, and after post assessment were followed for 10 weeks; waitlist participants were then also given the book with two months to complete it. Overall, participants showed significant improvement in psychological health. Significant preventive effects for depression and anxiety were observed along with significant ameliorative effects for those in the clinical ranges of depression, anxiety and stress. Follow up general mental health, depression, and anxiety outcomes were related to the manner in which participants used the workbook and to post levels of psychological flexibility. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. In vitro biofilm formation of commensal and pathogenic Escherichia coli strains: impact of environmental and genetic factors

    DEFF Research Database (Denmark)

    Reisner, A.; Krogfelt, Karen; Klein, B.M.


    Our understanding of Escherichia coli biofilm formation in vitro is based on studies of laboratory K-12 strains grown in standard media. However, pathogenic E. coli isolates differ substantially in their genetic repertoire from E. coli K-12 and are subject to heterogeneous environmental condition...

  16. Simulation of the rate of transfer of antibiotic resistance between Escherichia coli strains cultured under well controlled environmental conditions

    NARCIS (Netherlands)

    Smelt, J.P.; Hoefsloot, H.C.; de Koster, C.G.; Schuurmans, J.M.; ter Kuile, B.H.; Brul, S.


    It was demonstrated that the tetracycline resistance plasmid in Escherichia coli resembling K-12 23:06 containing the E. coli plasmid DM0133 could be transferred to tetracycline sensitive E. coli K-12 MG1655 YFP. The sensitive recipient strain has a slight metabolic advantage in continuous

  17. Efficacy of the World Wide Web in K-12 environmental education (United States)

    York, Kimberly Jane


    Despite support by teachers, students, and the American public in general, environmental education is not a priority in U.S. schools. Teachers face many barriers to integrating environmental education into K--12 curricula. The focus of this research is teachers' lack of access to environmental education resources. New educational reforms combined with emerging mass communication technologies such as the Internet and World Wide Web present new opportunities for the infusion of environmental content into the curriculum. New technologies can connect teachers and students to a wealth of resources previously unavailable to them. However, significant barriers to using technologies exist that must be overcome to make this promise a reality. Web-based environmental education is a new field and research is urgently needed. If teachers are to use the Web meaningfully in their classrooms, it is essential that their attitudes and perceptions about using this new technology be brought to light. Therefore, this exploratory research investigates teachers' attitudes toward using the Web to share environmental education resources. Both qualitative and quantitative methods were used to investigate this problem. Two surveys were conducted---self-administered mail survey and a Web-based online survey---to elicit teachers perceptions and comments about environmental education and the Web. Preliminary statistical procedures including frequencies, percentages and correlational measures were performed to interpret the data. In-depth interviews and participant-observation methods were used during an extended environmental education curriculum development project with two practicing teachers to gain insights into the process of creating curricula and placing it online. Findings from the both the mail survey and the Web-based survey suggest that teachers are interested in environmental education---97% of respondents for each survey agreed that environmental education should be taught in K

  18. Developing Partnerships between Higher Education Faculty, K-12 Science Teachers, and School Administrators via MSP initiatives: The RITES Model (United States)

    Caulkins, J. L.; Kortz, K. M.; Murray, D. P.


    The Rhode Island Technology Enhanced Science Project (RITES) is a NSF-funded Math and Science Partnership (MSP) project that seeks to improve science education. RITES is, at its core, a unique partnership that fosters relationships between middle and high school science teachers, district and school administrators, higher education (HE) faculty members, and science education researchers. Their common goal is to enhance scientific inquiry, increase classroom technology usage, and improve state level science test scores. In one of the more visible examples of this partnership, middle and high school science teachers work closely with HE science faculty partners to design and teach professional development (PD) workshops. The PD sessions focus on technology-enhanced scientific investigations (e.g. use of probes, online simulations, etc.), exemplify inquiry-based instruction, and relate expert content knowledge. Teachers from these sessions express substantial satisfaction in the program, report increased comfort levels in teaching the presented materials (both via post-workshop surveys), and show significant gains in content knowledge (via pre-post assessments). Other benefits to this kind of partnership, in which K-12 and HE teachers are considered equals, include: 1) K-12 teachers are empowered through interactions with HE faculty and other science teachers in the state; 2) HE instructors become more informed not only about good pedagogical practices, but also practical aspects of teaching science such as engaging students; and 3) the PD sessions tend to be much stronger than ones designed and presented solely by HE scientists, for while HE instructors provide content expertise, K-12 teachers provide expertise in K-12 classroom practice and implementation. Lastly, the partnership is mutually beneficial for the partners involved because both sides learn practical ways to teach science and inquiry at different levels. In addition to HE faculty and K-12 science teacher

  19. Adaptive responses to cefotaxime treatment in ESBL-producing Escherichia coli and the possible use of significantly regulated pathways as novel secondary targets

    DEFF Research Database (Denmark)

    Møller, Thea S. B.; Rau, Martin Holm; Bonde, Charlotte S


    -fold). Inhibition and/or mutations in other genes that were significantly regulated, belonging to energy synthesis, purine synthesis, proline uptake or potassium uptake, also rendered the resistant bacteria more susceptible to cefotaxime. The results show that ESBL-producing E. coli adapt to treatment...... that can be used to combat the resistant bacteria. Strains of E. coli MG1655 encoding blaCTX-M-1 from an IncI1 plasmid and from the chromosome were challenged with cefotaxime corresponding to inhibitory concentrations, and transcriptional patterns were compared with growth without or with very low...... concentrations of cefotaxime by RNA sequencing. Significantly regulated pathways were inhibited with suitable inhibitors, or genes encoding the enzymes of the regulated pathways were knocked out. The ability of the bacteria to grow in the presence of cefotaxime was determined. Chequerboard assays were utilized...

  20. Brain Based Learning: K-12 Teachers' Preferred Methods of Science Instruction (United States)

    Mansy, Donna Lachman

    The purpose of this quantitative study was to investigate Brain Based Learning (BBL) techniques in teaching science. Participants included 216 K-12, full-time, regular education teachers from 8 Northeast Tennessee school systems who taught at least 1 science class. Specifically this research was guided by 7 research questions on teachers' perceptions and practices in teaching science. Data were collected by a survey that consisted of 82 statements where teachers rated their level of agreement and was distributed online via Survey Monkey. The first portion of my survey included demographic identifiers, teachers' knowledge of the term BBL, and inquiries regarding science background and training. The remainder of the statements were focused on teachers' perceptions and practices of BBL strategies in teaching science. The final item was open-ended and allowed teachers to share comments related to teaching science. For statements 6-81, participants responded by using a 5-point Likert scale that ranged from 1 (strongly disagree) to 5 ( strongly agree). Quantitative data were analyzed with a series of independent samples t tests, one-way analysis of variance tests, and a Pearson correlation coefficient. The results of the study indicate that teachers' perceptions are positively correlated to their self-reported practices. Females, in general, and elementary teachers tend to practice BBL strategies in teaching science significantly more than other subgroups.

  1. Impact of an Education Intervention on Missouri K-12 School Disaster and Biological Event Preparedness. (United States)

    Rebmann, Terri; Elliott, Michael B; Artman, Deborah; VanNatta, Matthew; Wakefield, Mary


    A 2011 nationwide school pandemic preparedness study found schools to be deficient. We examined the impact of a school nurse educational intervention aimed at improving K-12 school biological event preparedness. Missouri Association of School Nurses (MASN) members were e-mailed a survey link in fall 2013 (ie, preintervention), links to online education modules (ie, intervention) in late fall, and a postintervention survey link in spring, 2014. School biological event readiness was measured using 35 indicators, for a possible score range of 0-35. A paired t-test compared pre- to postintervention preparedness scores. A total of 133 school nurses (33.6% response rate) completed a survey; 35.3% of those (N = 47) completed both pre- and postintervention survey that could be matched. Pre- and postintervention preparedness scores ranged from 5 to 28.5 (x‾ = 13.3) and 6.5 to 25 (x‾ = 14.8), respectively. Postintervention scores were significantly higher than preintervention scores for those who watched at least 1 module (t = -2.3, p education intervention was effective at improving school preparedness, though the impact was small. The education intervention needs to be reassessed, especially in regard to providing a longer intervention period. © 2016, American School Health Association.

  2. K-12 Teacher Understanding of Energy Conservation: Conceptual Metaphor, Dissipation, and Degradation (United States)

    Daane, Abigail R.

    In K-12 educational settings, conservation of energy is typically presented in two ways: the conservation of energy principle (energy is neither created nor destroyed) and the sociopolitical need to conserve energy (we guard against energy being used up). These two meanings of conservation typically remain disconnected from each other and can appear contradictory, even after instruction. In an effort to support teachers in building robust understandings of energy from their existing knowledge, I designed a study to investigate the productive ideas in K-12 teachers' conversations about energy. A micro-analysis of discourse, gestures, and artifacts of professional development courses revealed teachers' productive ideas about three aspects of energy: conceptual metaphor, dissipation and degradation. In learning about energy, K-12 teachers come to use conceptual metaphors in their own language and value attending to students' metaphorical language as a means of formative assessment. Teachers' conversations about dissipation suggest that apparent difficulties with energy conservation may have their roots in a strong association between forms of energy (thermal) and their perceptible indicators (warmth). Teachers address this challenge by employing an exaggeration strategy to locate the dissipated thermal energy, making the energy indicator perceptible. Finally, teachers' unprompted statements about sociopolitical aspects of energy are related to both statements from the NGSS and aspects of energy degradation. I conclude that energy conservation can be better taught and learned in K-12 Education by: 1) understanding and applying conceptual metaphors about energy in K-12 settings, 2) using prior experiences to better understand dissipative energy processes involving imperceptible thermal energy, thereby understanding how energy conservation applies in all situations, and 3) connecting productive ideas about sociopolitical aspects of energy to canonical physics. Keywords

  3. Advanced Energy Retrofit Guide: Practical Ways to Improve Energy Performance, K-12 Schools (Book)

    Energy Technology Data Exchange (ETDEWEB)


    The U.S. Department of Energy developed the K-12 Advanced Energy Retrofit Guide to provide specific methodologies, information, and guidance to help energy managers and other stakeholders plan and execute energy efficiency improvements. We emphasize actionable information, practical methodologies, diverse case studies, and unbiased evaluation of the most promising retrofit measure for each building type. K-12 schools were selected as one of the highest priority building sectors, because schools affect the lives of most Americans. They also represent approximately 8% of the energy use and 10% of the floor area in commercial buildings.

  4. Financing Energy Upgrades for K-12 School Districts: A Guide to Tapping into Funding for Energy Efficiency and Renewable Energy Improvements

    Energy Technology Data Exchange (ETDEWEB)

    Goggio Borgeson, Merrian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Zimring, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division


    This guide focuses on clean energy financing options for school administrators, facility managers, and other K-12 school decision makers who are considering investments in high performance school projects. This guide explicitly focuses on comprehensive energy upgrades, those that involve multiple measures and are targeted toward achieving significant energy savings. Successful implementation of clean energy upgrades in schools is a matter of understanding the opportunity, making the commitment, and creatively tapping into available financing. This guide attempts to provide the foundation needed for successful projects in U.S. schools. It walks through the financing options available to K-12 schools and provides case studies of six school districts from around the country.

  5. K-12 Online Lesson Alignment to the Principles of Universal Design for Learning: The Khan Academy (United States)

    Smith, Sean J.; Harvey, Evelyn E.


    The field of K-12 education is being transformed, with an influx of students, including those with identified disabilities, engaging in blended and fully online learning. While online learning shows promise for students with disabilities through flexible content and personalised instruction, concerns regarding accessibility and appropriateness of…

  6. A Nonverbal Language for Imagining and Learning: Dance Education in K-12 Curriculum (United States)

    Hanna, Judith Lynne


    Curriculum theorists have provided a knowledge base concerning aesthetics, agency, creativity, lived experience, transcendence, learning through the body, and the power of the arts to engender visions of alternative possibilities in culture, politics, and the environment. However, these theoretical threads do not reveal the potential of K-12 dance…

  7. Exploring a Paperless Business Administrative System (BAS) Implementation in a K-12 School (United States)

    Issa, Marwan M.


    The primary purpose of this qualitative study was to investigate how a paperless BAS can affect the overall performance of a school's administrative activities. The research included direct observation, survey questionnaires, document review, and both structured and unstructured interviews. The selected school, a K-12 charter school, was an ideal…

  8. Effects of a Haptic Augmented Simulation on K-12 Students' Achievement and Their Attitudes Towards Physics (United States)

    Civelek, Turhan; Ucar, Erdem; Ustunel, Hakan; Aydin, Mehmet Kemal


    The current research aims to explore the effects of a haptic augmented simulation on students' achievement and their attitudes towards Physics in an immersive virtual reality environment (VRE). A quasi-experimental post-test design was employed utilizing experiment and control groups. The participants were 215 students from a K-12 school in…

  9. Job Satisfaction, Organizational Commitment, and Turnover Intention of Online Teachers in the K-12 Setting (United States)

    Larkin, Ingle M.; Brantley-Dias, Laurie; Lokey-Vega, Anissa


    The purpose of this study was to measure and explore factors influencing K-12 online teachers' job satisfaction, organizational commitment, and turnover intentions. Using Maslow's Hierarchy of Needs (1954), Herzberg's Two-Factor Theory of Satisfaction (1959, 1968), Meyer and Allen's measure of Organizational Commitment (1997), and Fishbein and…

  10. Evaluating ICT Integration in Turkish K-12 Schools through Teachers' Views (United States)

    Aydin, Mehmet Kemal; Gürol, Mehmet; Vanderlinde, Ruben


    The current study aims to explore ICT integration in Turkish K-12 schools purposively selected as a representation of F@tih and non-F@tih public schools together with a private school. A convergent mixed methods design was employed with a multiple case strategy as such it will enable to make casewise comparisons. The quantitative data was…

  11. Limitations upon Legitimate Authority to Suspend and Expel K-12 Public School Students: A Moral Analysis (United States)

    Ladenson, Robert F.


    This article presents a moral analysis of the limitations upon legitimate authority to suspend and expel students in K-12 public schools, and it brings this analysis to bear on a pair of difficult disciplinary cases. The analysis is grounded in a defense of a child's right to receive a public education. It identifies the minimum content of that…

  12. Monitoring Progress toward Successful K-12 STEM Education: A Nation Advancing? (United States)

    National Academies Press, 2013


    Following a 2011 report by the National Research Council (NRC) on successful K-12 education in science, technology, engineering, and mathematics (STEM), Congress asked the National Science Foundation to identify methods for tracking progress toward the report's recommendations. In response, the NRC convened the Committee on an Evaluation Framework…

  13. Native Chinese-Speaking K-12 Language Teachers' Beliefs and Practices (United States)

    Lü, Chan; Lavadenz, Magaly


    This study investigated the relationships between the beliefs and practices of K-12 native Chinese teachers on Chinese language and literacy instruction. Using a descriptive-exploratory design, this study employed a mixed-methods approach consisting of three steps: (1) a teacher beliefs questionnaire, (2) classroom observations and videotaping,…

  14. An Empirical Evaluation of Distance Learning's Effectiveness in the K-12 Setting (United States)

    Harris-Packer, Jerilyn D.; Ségol, Geneviève


    This study evaluated the effect of online instruction on the academic achievement of K--12 students in ten states as measured by the percentage of proficient students in reading and mathematics at the school level. We used publicly available data provided by the Department of Education in Florida, Michigan, Minnesota, Nevada, Ohio, Pennsylvania,…

  15. Blueprint for Incorporating Service Learning: A Basic, Developmental, K-12 Service Learning Typology (United States)

    Terry, Alice W.; Bohnenberger, Jann E.


    Citing the need for a basic, K-12 developmental framework for service learning, this article describes such a model. This model, an inclusive typology of service learning, distinguishes three levels of service learning: Community Service, Community Exploration, and Community Action. The authors correlate this typology to Piaget's cognitive…

  16. The Influence of Lean on K-12 District Management: A Case Study (United States)

    Brown, Beverly


    For decades, policymakers and educators have focused on public school equity and adequacy, while paying little attention to efficiency. This qualitative single case study was designed to capture explicit information about Lean management, operations, and culture in a K-12 Michigan school district engaged in Lean training and implementation for a…

  17. Dual Enrollment from Two Points of View: Higher Education and K-12 (United States)

    Kilgore, Wendy; Wagner, Ellen


    While dual enrollment fills a similar student success niche in both higher and K-12 education, the administrative perspectives of these two entities do not always align. This article highlights the groups' similarities and differences in perspective and proposes implications for practice.

  18. Plickers: A Formative Assessment Tool for K-12 and PETE Professionals (United States)

    Krause, Jennifer M.; O'Neil, Kason; Dauenhauer, Brian


    Classroom response systems have become popular in K-12 and higher education settings in recent years in order to gauge student learning. The physical education environment is unique in that it is difficult to manage the technology associated with these systems, and therefore, student assessment can be cumbersome. A free classroom response system…

  19. The Chem-E-Car as a Vehicle for Service Learning through K-12 Outreach (United States)

    Chirdon, William


    This article presents the results of combining the American Institute of Chemical Engineers' (AIChE) Chem-E-Car competition activities with engineering outreach to K-12 students in a service-learning course. Survey results are presented to show how the program develops technical skills as well as leadership, teamwork, and communication skills in…

  20. Online K-12 Teachers' Perceptions and Practices of Supporting Self-Regulated Learning (United States)

    Huh, Yeol; Reigeluth, Charles M.


    With growing interest in and popularity of online learning and lifelong learners, students' ability to be engaged in self-regulated learning (SRL) has become more important. Moreover, online learning is becoming an important feature of K-12 education. Although SRL is known to be important and teachable, little research has been conducted on…

  1. Developing the Principal Technology Leadership Competency Indicators for Technical High Schools in K-12 in Taiwan (United States)

    Shyr, Wen-Jye


    The purpose of this study was to develop principal technology leadership competency indicators for technical high schools in K-12 in Taiwan in order to improve the effectiveness of school administration and teaching. In the first part of the study, five experts in the technology leadership field are interviewed to explore the technology leadership…

  2. The Effect of Professional Development on Teacher Attitudes toward Online Learning in K-12 Education (United States)

    Savakinas, Christy A.


    The purpose of this study was to examine how teacher attitudes toward online learning in K-12 education vary before, during, and after participation in a professional development program focused on ePedagogy and online course development. The study also examined which Key Design Factors, as identified by Wells (2007), influence teachers'…

  3. African Dance Aesthetics in a K-12 Dance Setting: From History to Social Justice (United States)

    Ward, Sheila A.


    This article invites the reader to gain a deeper understanding of the aesthetics of African-based dance through the elements of tradition, transformation, and social justice. A discussion of the aesthetics of African dances within Africa and throughout the African diaspora opens the doors to present these dances in a K-12 setting, to explore a…

  4. Mixed Methods Evaluation of Statewide Implementation of Mathematics Education Technology for K-12 Students (United States)

    Brasiel, Sarah; Martin, Taylor; Jeong, Soojeong; Yuan, Min


    An extensive body of research has demonstrated that the use in a K-12 classroom of technology, such as the Internet, computers, and software programs, enhances the learning of mathematics (Cheung & Slavin, 2013; Cohen & Hollebrands, 2011). In particular, growing empirical evidence supports that certain types of technology, such as…

  5. Technology-Related Strategies Used by Educational Leaders to Increase Prosocial Behavior in K-12 Schools (United States)

    Beers, Jason Ronald


    Purpose. The purpose of this study was to identify technology-related strategies used by educational leaders to increase prosocial behavior in K-12 schools. Information and communication technology (ICT) is developing at a rapid rate and is becoming more ubiquitous among students. Discovering and understanding common technology-related strategies…

  6. Students Doing Chemistry: A Hand-On Experience for K-12 (United States)

    Selco, Jodye I.; Bruno, Mary; Chan, Sue


    A hands-on, minds-on inquiry chemistry experiment was developed for use in K-12 schools that enables students to combine the chemicals of their choice and observe the results. The chemistry involved is water based and builds upon acid-base, double displacement, and iodometric detection of starch reactions. Chemicals readily available in the…

  7. Netflixing Human Capital Development: Personalized Learning Technology and the Corporatization of K-12 Education (United States)

    Roberts-Mahoney, Heather; Means, Alexander J.; Garrison, Mark J.


    Advanced by powerful venture philanthropies, educational technology companies, and the US Department of Education, a growing movement to apply "big data" through "learning analytics" to create "personalized learning" is currently underway in K-12 education in the United States. While scholars have offered various…

  8. Preparing University Students to Lead K-12 Engineering Outreach Programmes: A Design Experiment (United States)

    Anthony, Anika B.; Greene, Howard; Post, Paul E.; Parkhurst, Andrew; Zhan, Xi


    This paper describes an engineering outreach programme designed to increase the interest of under-represented youth in engineering and to disseminate pre-engineering design challenge materials to K-12 educators and volunteers. Given university students' critical role as facilitators of the outreach programme, researchers conducted a two-year…

  9. A Study of the Tablet Computer's Application in K-12 Schools in China (United States)

    Long, Taotao; Liang, Wenxin; Yu, Shengquan


    As an emerging mobile terminal, the tablet computer has begun to enter into the educational system. With the aim of having a better understanding of the application and people's perspectives on the new technology in K-12 schools in China, a survey was conducted to investigate the tablet computer's application, user's perspectives and requirements…

  10. Measurement Invariance of the "Servant Leadership Questionnaire" across K-12 Principal Gender (United States)

    Xu, Lihua; Stewart, Trae; Haber-Curran, Paige


    Measurement invariance of the five-factor "Servant Leadership Questionnaire" between female and male K-12 principals was tested using multi-group confirmatory factor analysis. A sample of 956 principals (56.9% were females and 43.1% were males) was analysed in this study. The hierarchical multi-step measurement invariance test supported…

  11. K-12 Single-Sex Education: What Does the Research Say? ERIC Digest. (United States)

    Haag, Pamela

    Although research on the effects of K-12 single-sex education is inconclusive in general, some common themes emerge in the research literature. This Digest reviews that research with particular attention to effects on girls' attitudes and achievement. The Digest first discusses attitudinal variables (i.e., self-esteem and attitudes toward academic…

  12. Leading Effective Educational Technology in K-12 School Districts: A Grounded Theory (United States)

    Hill, Lara Gillian C.


    A systematic grounded theory qualitative study was conducted investigating the process of effectively leading educational technology in New Jersey public K-12 school districts. Data were collected from educational technology district leaders (whether formal or non-formal administrators) and central administrators through a semi-structured online…

  13. Using the van Hiele K-12 Geometry Learning Theory to Modify Engineering Mechanics Instruction (United States)

    Sharp, Janet M.; Zachary, Loren W.


    Engineering students use spatial thinking when examining diagrams or models to study structure design. It is expected that most engineering students have solidified spatial thinking skills during K-12 schooling. However, according to what we know about geometry learning and teaching, spatial thinking probably needs to be explicitly taught within…

  14. Is K-12 Blended Learning Disruptive? An Introduction to the Theory of Hybrids (United States)

    Christensen, Clayton M.; Horn, Michael B.; Staker, Heather


    The Clayton Christensen Institute for Disruptive Innovation, formerly the Innosight Institute, has published three papers describing the rise of K-12 blended learning--that is, formal education programs that combine online learning and brick-and-mortar schools. This fourth paper is the first to analyze blended learning through the lens of…

  15. Factors that Affect the Adoption and Use of Electronic Mail by K-12 Foreign Language Educators. (United States)

    Shelley, Janine Onffroy


    Reports the results of electronic mail instruction given to K-12 foreign-language teachers during workshops. Factors found to influence workshop participants' adoption of email included training, the need to keep up with educational technology trends, availability of an easy-to-use system, hands-on experience, school support, and individual…

  16. A Longitudinal Evaluation Study of a Science Professional Development Program for K-12 Teachers: NERDS (United States)

    Ewing-Taylor, Jacque M.


    A longitudinal evaluation study of a science professional development program for K-12 teachers was conducted using the CIPP evaluation model. Eleven years of program data were described and analyzed. Elementary teachers comprised 62% of the 384 participants, 17% of all participants were middle school teachers, and 13% of all participants were…

  17. Benefits and Pitfalls: Simple Guidelines for the Use of Social Networking Tools in K-12 Education (United States)

    Huffman, Stephanie


    The article will outline a framework for the use of social networking tools in K-12 education framed around four thought provoking questions: 1) what are the benefits and pitfalls of using social networking tools in P-12 education, 2) how do we plan effectively for the use of social networking tool, 3) what role does professional development play…

  18. Makerspaces: The Next Iteration for Educational Technology in K-12 Schools (United States)

    Strycker, Jesse


    With the continually growing number of computers and mobile devices available in K-12 schools, the need is dwindling for dedicated computer labs and media centers. Some schools are starting to repurpose those facilities into different kinds of exploratory learning environments known as "makerspaces". This article discusses this next…

  19. Increasing Diversity in K-12 School Leadership. Policy Brief 2018-3 (United States)

    Castro, Andrene; Germain, Emily; Gooden, Mark


    Principals represent the most "visible" form of leadership in schools, but current workforce data show that K-12 school principals are overwhelmingly white and fail to reflect the diversity within the student population. With increased policy focus on teacher diversity, equal attention must also be directed towards the lack of diversity…

  20. Manifesting Destiny: Re/Presentations of Indigenous Peoples in K-12 U.S. History Standards (United States)

    Shear, Sarah B.; Knowles, Ryan T.; Soden, Gregory J.; Castro, Antonio J.


    In this mixed-methods study, we use a postcolonial framework to investigate how state standards represent Indigenous histories and cultures. The research questions that guided this study include: (a) What is the frequency of Indigenous content (histories, cultures, current issues) covered in state-level U.S. history standards for K-12? (b) What is…

  1. Modern Rhythmic Gymnastics. A Supplement to the K-12 Physical Education Curriculum Guide. Curriculum Support Series. (United States)

    Willoughby, Heather; Plumton, Diane

    This resource package has been designed to assist the instructor in using modern rhythmic gymnastics (MRG) to support the objectives cited in the "K-12 Physical Education Curriculum Guide," developed by the Manitoba Department of Education. MRG is based on scientific principles of movement, and makes use of small, hand-held apparatus…

  2. Explaining Technology Integration in K-12 Classrooms: A Multilevel Path Analysis Model (United States)

    Liu, Feng; Ritzhaupt, Albert D.; Dawson, Kara; Barron, Ann E.


    The purpose of this research was to design and test a model of classroom technology integration in the context of K-12 schools. The proposed multilevel path analysis model includes teacher, contextual, and school related variables on a teacher's use of technology and confidence and comfort using technology as mediators of classroom technology…

  3. K-12 Teachers' Perceptions of and Their Satisfaction with Interaction Type in Blended Learning Environments (United States)

    Kuo, Yu-Chun; Belland, Brian R.; Schroder, Kerstin E. E.; Walker, Andrew E.


    Blended learning is an effective approach to instruction that combines features of face-to-face learning and computer-mediated learning. This study investigated the relationship between student perceptions of three types of interaction and blended learning course satisfaction. The participants included K-12 teachers enrolled in a graduate-level…

  4. Arts Education K-12: Teacher Handbook. North Carolina Competency-Based Curriculum Subject-by-Subject. (United States)

    Chapman, Barbara Holland

    The North Carolina arts education curriculum encompasses K-12 programs in dance, folk arts, music, theater arts, and visual arts. It is designed to provide a scope and sequence which encourages students to develop the essential senses of sight, hearing, smell, taste, touch, and kinetic awareness. It provides opportunities to develop thinking…

  5. Surveying Chinese In-Service K12 Teachers' Technology, Pedagogy, and Content Knowledge (United States)

    Liu, Qingtang; Zhang, Si; Wang, Qiyun


    Technology, pedagogy, and content knowledge (TPACK) has been considered as a promising theoretical framework to guide teacher educators in designing and developing in-service K12 teacher education programs. However, it seems unclear whether in-service teachers have different TPACK perceptions when entering the education programs. This study…

  6. A Professional Learning Program Designed to Increase K-12 Teachers' Instructional Technology Use (United States)

    Spencer, Lisa A.


    Despite the ready availability of many instructional-technology resources, many teachers in the researched Maryland school district are uncomfortable using technology to deliver content. This concurrent mixed methods case study examined the impact of Sharing Technology with Educators Program (STEP) on 269 K-12 teachers' technology use. The study…

  7. Developing a Nationwide K-12 Outreach Model: Physiology Understanding (PhUn) Week 10 Years Later (United States)

    Stieben, Margaret; Halpin, Patricia A.; Matyas, Marsha Lakes


    Since 2005, nearly 600 Physiology Understanding Week (PhUn Week) events have taken place across the U.S., involving American Physiological Society (APS) members in K-12 outreach. The program seeks to build student understanding of physiology and physiology careers, assist teachers in recognizing physiology in their standards-based curriculum, and…

  8. Mobile Apps for Reflection in Learning: A Design Research in K-12 Education (United States)

    Leinonen, Teemu; Keune, Anna; Veermans, Marjaana; Toikkanen, Tarmo


    This study takes a design-based research approach to explore how applications designed for mobile devices could support reflection in learning in K-12 education. Use of mobile devices is increasing in schools. Most of the educational apps support single-person use of interactive learning materials, simulations and learning games. Apps designed to…

  9. Environmental Education and K-12 Student Outcomes: A Review and Analysis of Research (United States)

    Ardoin, Nicole M.; Bowers, Alison W.; Roth, Noelle Wyman; Holthuis, Nicole


    Many practitioners and researchers describe academic and environmental benefits of environmental education for kindergarten through twelfth grade (K-12) students. To consider the empirical underpinnings of those program descriptions, we systematically analyzed the peer-reviewed literature (1994-2013), focusing on outcomes of environmental…

  10. The Design, Implementation and Evaluation of Korean K-12 Teacher Training Workshops

    Directory of Open Access Journals (Sweden)

    Sang Yee Cheon


    Full Text Available In contrast to public K-12 schools with relatively few Korean language resources, there are about 1,400 Korean community schools in the United States. In most states, K-12 students who are interested in learning about Korean language and culture have no other option but to attend Korean community schools. The purpose of this study is to report on enhanced teacher training workshops for Korean K-12 and community school teachers by seeking a remedy for limitations and problems that previous studies identified. This study will cover the current status of K-12 and Korean community schools in the United States, a summary of a needs analysis of Korean community schools in Hawaii issued in a previous study, the design and implementation of the workshop for Korean language teachers, and the results of the participants’ responses from their exit survey. This report will also include the conclusion of the study, its limitations and implications for future workshops relevant to teachers of other Less Commonly Taught Languages (LCTLs.

  11. Commentary: Mis-Education in K-12 Teaching about Hmong Culture, Identity, History and Religion

    Directory of Open Access Journals (Sweden)

    Kou Yang


    Full Text Available This commentary article discusses several examples of inaccurate information about the Hmong presented in contemporary materials produced by school district staff and/or published by mainstream publishers in the United States for use with the K-12 market to teach about Hmong culture and history.

  12. California and the "Common Core": Will There Be a New Debate about K-12 Standards? (United States)

    EdSource, 2010


    A growing chorus of state and federal policymakers, large foundations, and business leaders across the country are calling for states to adopt a common, rigorous body of college- and career-ready skills and knowledge in English and mathematics that all K-12 students will be expected to master by the time they graduate. This report looks at the…

  13. The Cost Burden to Minnesota K-12 when Children Are Unprepared for Kindergarten. [Summary (United States)

    Chase, Richard; Coffee-Borden, Brandon; Anton, Paul; Moore, Christopher; Valorose, Jennifer


    This summary presents highlights of "The Cost Burden to Minnesota K-12 when Children Are Unprepared for Kindergarten" [ED511612]. A number of studies document the long-term public and societal benefits of early childhood education, including the reduced costs associated with child welfare, public assistance, crime and incarceration, and…

  14. Crossing the Bridge: Transitioning from a K-12 Teacher to a College Professor (United States)

    Page, Steven; Jenks, Charles


    This is a qualitative study that was conducted to gain a better understanding of the experiences of professors in Colleges of Education who were former K-12 teachers. The study presents the responses of eighty-nine professors from across the United States. Coding based on the university setting (national, large regional, small regional) in which…

  15. An Evaluation of the Conditions, Processes, and Consequences of Laptop Computing in K-12 Classrooms (United States)

    Cavanaugh, Cathy; Dawson, Kara; Ritzhaupt, Albert


    This article examines how laptop computing technology, teacher professional development, and systematic support resulted in changed teaching practices and increased student achievement in 47 K-12 schools in 11 Florida school districts. The overview of a large-scale study documents the type and magnitude of change in student-centered teaching,…

  16. Laptops in the K-12 Classrooms: Exploring Factors Impacting Instructional Use (United States)

    Inan, Fethi A.; Lowther, Deborah L.


    The purpose of this study was to examine factors affecting teachers' integration of laptops into classroom instruction. A research-based path model was tested based on data gathered from 379 K-12 school teachers to examine direct and indirect contributions of relevant institutional factors (overall support for school technology, technical support,…

  17. A Field Study of Telepractice for School Intervention Using the ASHA NOMS K-12 Database (United States)

    Gabel, Rodney; Grogan-Johnson, Sue; Alvares, Robin; Bechstein, Leah; Taylor, Jacquelyn


    The purpose of this article is to describe the characteristics and effectiveness of a telepractice speech-language therapy program for school-age children. Outcome data related to the caseload, type and amount of intervention, and student progress from a school-based telepractice therapy program were compared with the K-12 Schools National…

  18. Teaching and Learning with Mobile Computing Devices: Case Study in K-12 Classrooms (United States)

    Grant, Michael M.; Tamim, Suha; Brown, Dorian B.; Sweeney, Joseph P.; Ferguson, Fatima K.; Jones, Lakavious B.


    While ownership of mobile computing devices, such as cellphones, smartphones, and tablet computers, has been rapid, the adoption of these devices in K-12 classrooms has been measured. Some schools and individual teachers have integrated mobile devices to support teaching and learning. The purpose of this qualitative research was to describe the…

  19. How Do K-12 Students' Manage Applications on Their Mobile Devices? (United States)

    Aladjem, Ruthi; Hardof, Sharon


    Personal information management (PIM) is a research field that examines the activities by which users save, organize and retrieve personal information items. PIM is a one of the essential new literacies for learners in the 21st century. This paper reports results from a pilot study that explored PIM practices and strategies of K-12 students, on…

  20. K-12 Student Use of Web 2.0 Tools: A Global Study (United States)

    Toledo, Cheri; Shepard, MaryFriend


    Over the past decade, Internet use has increased 445% worldwide. This boom has enabled widespread access to online tools and digital spaces for educational practices. The results of this study of Web 2.0 tool use in kindergarten through high school (K-12) classrooms around the world will be presented. A web-based survey was sent out through online…

  1. Calibration of the AG23K-12.5 Feed Horn

    DEFF Research Database (Denmark)

    Pivnenko, Sergey; Breinbjerg, Olav

    This report documents the calibration measurement of the dual-linearly polarized AG23K-12.5 feed horn. The measurement comprises on-axis gain, on-axis polarization characteristics, and input reflection coefficient at 701 frequencies in the frequency range from 9.0-16.0 GHz. The measurement...

  2. Immigration and Education: What Should K-12 Teachers, School Administrators, and Staff Know? (United States)

    Rubinstein-Avila, Eliane


    We are currently living in an era of mass global migration. Therefore, it is a pertinent time to reflect on the challenges and the possibilities inherent in educating immigrant and refugee children. Because of the importance immigration has played in the history of the United States, it may be assumed that American K-12 teachers and school…

  3. Perceptions and Experiences of K-12 Educational Leaders in Response to the 27 April 2011 Tornadoes (United States)

    Bishop, William E.; Fifolt, Matthew; Peters, Gary B.; Gurley, D. Keith; Collins, Loucrecia


    The purpose of this phenomenological study was to capture first-hand accounts of K-12 educational leaders whose school districts were directly affected by the deadly 27 April 2011 tornadoes in rural Alabama, USA. This study was framed by the literature base of leadership; specifically crisis leadership and resilience theory. Findings are organised…

  4. Learning Analysis of K-12 Students' Online Problem Solving: A Three-Stage Assessment Approach (United States)

    Hu, Yiling; Wu, Bian; Gu, Xiaoqing


    Problem solving is considered a fundamental human skill. However, large-scale assessment of problem solving in K-12 education remains a challenging task. Researchers have argued for the development of an enhanced assessment approach through joint effort from multiple disciplines. In this study, a three-stage approach based on an evidence-centered…

  5. Reconsidering Genre Theory in K-12 Schools: A Response to School Reforms in the United States (United States)

    Gebhard, Meg; Harman, Ruth


    Education reforms in the United States have placed new demands on English language learners (ELLs) and their teachers in K-12 public schools. In response, many teachers, teacher educators, and literacy scholars are reexamining genre theory and genre-based pedagogy as a way of supporting the academic literacy development of the growing number of…

  6. Comparing Cross-Cultural Multicultural Self-Awareness among K-12 In-Service School Teachers (United States)

    Koyama, Chieko; Plash, Shawn; Davis, Kirk


    The present study explored multicultural self-awareness among 134 K-12 in-service school teachers using the Cultural Diversity Awareness Inventory (CDAI). The results were compared to Yeung's (2006), allowing for a comparison between Eastern and Western cultures. A composite score was generated for each of the five areas measured by the CDAI. A…

  7. Development of Design Guidance for K-12 Schools from 30% to 50% Energy Savings: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Pless, S.; Torcellini, P.; Long, N.


    This paper describes the development of energy efficiency recommendations for achieving 30% whole-building energy savings in K-12 schools over levels achieved by following the ANSI/ASHRAE/IESNA Standard 90.1. These design recommendations look at building envelope, fenestration, lighting systems (including electrical lights and daylighting), HVAC systems, building automation and controls, outside air treatment, and service water heating.

  8. Single-Subject Designs and Action Research in the K-12 Setting (United States)

    Forbes, Sean A.; Ross, Margaret E.; Chesser, Svetlana S.


    In as much as educational research is concerned with individual student assessment and development, it is surprising that single-subject designs are not more readily utilized in classroom-based action research. The purpose of this article is to emphasize benefits of single-subject research in the K-12 setting, given that teachers teach and assess…

  9. Leading by Following: An Analysis of How K-12 School Leaders Use Twitter (United States)

    Sauers, Nicholas J.; Richardson, Jayson W.


    This study analyzed how active Twitter users who are also school leaders used the tool. The researchers collaboratively identified K-12 school leaders who were active on Twitter and then collected tweets from those school leaders. The final sample for this study included 115 Twitter users and over 180,000 tweets from those individuals. The results…

  10. Empowering Educators through Teacher Research: Promoting Qualitative Inquiry among K-12 Educators (United States)

    Clarke, E. Jason


    The desire to find pedagogically effective uses of technology in K-12 education has exposed the need for reliable professional development programs that empower teachers to identify the problems and needs they have in their classrooms, apply a process of systematic inquiry in order to discover solutions to those problems, and to share those…

  11. How to Implement Rigorous Computer Science Education in K-12 Schools? Some Answers and Many Questions (United States)

    Hubwieser, Peter; Armoni, Michal; Giannakos, Michail N.


    Aiming to collect various concepts, approaches, and strategies for improving computer science education in K-12 schools, we edited this second special issue of the "ACM TOCE" journal. Our intention was to collect a set of case studies from different countries that would describe all relevant aspects of specific implementations of…

  12. iPads in K-12 Schools: A Grounded Theory Study of Value (United States)

    Townsend, Mary Beth


    This qualitative grounded theory study investigated the value of iPads in K-12 schools when used in one-to-one ratios. The purpose of the study was to understand the perspectives of teachers using iPads in one-to-one ratios for teaching and learning in the classroom and administrators responsible for the implementation of these devices. The…

  13. The Preparation of Teacher Candidates for K-12 Online Learning Environments: A Case Study (United States)

    Williams, Nicole V.


    The purpose of this study was to determine how teacher education programs may better prepare teacher candidates to teach in K-12 online learning environments. The primary research question addressed was: What specific knowledge, skills, and dispositions should teacher education programs include in their curriculum to better prepare teacher…

  14. Teacher Certification of American Sign Language Faculty at K-12 and Higher Education Institutions (United States)

    Fox, Ashley Leann Chance


    American Sign Language (ASL) is ranked fourth among heritage languages taken by students in the United States. The number of ASL classes offered at the K-12 and Institutions of Higher Education are on the rise, yet the number of certified ASL teachers remains stagnant. This study examines the reasons why American Sign Language teachers choose to…

  15. The Debate of Evolution versus Intelligent Design: Is Critical Thinking Occurring among K-12 Students? (United States)

    Hoodman, Kyle Nathan


    This study investigates how evolution versus intelligent design is handled in the public, private Christian, private Jewish, and Christian Home-school K-12 settings through a review of the current literature and by interviewing teachers in these educational venues. Fourteen public, private, and homeschool educators responded to an interview…

  16. Peer Mentoring and Peer Tutoring among K-12 Students: A Literature Review (United States)

    Goodrich, Andrew


    The purpose of this literature review is to examine research on peer mentoring among K-12 students to assist practitioners with how to incorporate these instructional techniques into their own music programs. Primary themes across the music education literature of peer mentoring include the role of music teachers, the role of students as they…

  17. Cisco Networking Academy: Next-Generation Assessments and Their Implications for K-12 Education (United States)

    Liu, Meredith


    To illuminate the possibilities for next-generation assessments in K-12 schools, this case study profiles the Cisco Networking Academy, which creates comprehensive online training curriculum to teach networking skills. Since 1997, the Cisco Networking Academy has served more than five million high school and college students and now delivers…

  18. Outstanding Science Trade Books for Students K-12: Books Published in 2015 (United States)

    Science and Children, 2016


    Science teachers and mentors continue to be challenged to meet the high expectations of "A Framework for K-12 Science Education" and the "Next Generation Science Standards" ("NGSS"). Indeed the "Framework" urges to help learners "[build] progressively more sophisticated explanations of natural…

  19. Trends in Technology Planning and Funding in Florida K-12 Public Schools (United States)

    Ritzhaupt, Albert Dieter; Hohlfeld, Tina N; Barron, Ann E.; Kemker, Kate


    This empirical research investigates trends in technology planning and funding in Florida's K-12 public schools between the 2003-04 and 2005-06 academic years. Survey items that focused on funding and planning issues on Florida's statewide school technology integration survey were analyzed using logistic models. Results indicate a significant…

  20. Networking K-12 Schools: Architecture Models and Evaluation of Costs and Benefits. (United States)

    Rothstein, Russell Isaac

    This thesis examines the cost and benefits of communication networks in K-12 schools using cost analysis of five technology models with increasing levels of connectivity. Data indicate that the cost of the network hardware is only a small fraction of the overall networking costs. PC purchases, initial training, and retrofitting are the largest…

  1. Identifying and Reconstructing Common Cold Misconceptions among Developing K-12 Educators (United States)

    Johnson, Marcus Lee; Bungum, Timothy


    Background: Common cold misconceptions may contribute to ill-informed decisions and recommendations made by K-12 educators who often encounter infected students. Understanding the structure of educators' misconceptions can be used to improve health instruction in teacher professional preparation programs. Purpose: The purposes of this project were…

  2. Engineering Design Skills Coverage in K-12 Engineering Program Curriculum Materials in the USA (United States)

    Chabalengula, Vivien M.; Mumba, Frackson


    The current "K-12 Science Education framework" and "Next Generation Science Standards" (NGSS) in the United States emphasise the integration of engineering design in science instruction to promote scientific literacy and engineering design skills among students. As such, many engineering education programmes have developed…

  3. Identification and validation of novel chromosomal integration and expression loci in Escherichia coli flagellar region 1.

    Directory of Open Access Journals (Sweden)

    Mario Juhas

    Full Text Available Escherichia coli is used as a chassis for a number of Synthetic Biology applications. The lack of suitable chromosomal integration and expression loci is among the main hurdles of the E. coli engineering efforts. We identified and validated chromosomal integration and expression target sites within E. coli K12 MG1655 flagellar region 1. We analyzed five open reading frames of the flagellar region 1, flgA, flgF, flgG, flgI, and flgJ, that are well-conserved among commonly-used E. coli strains, such as MG1655, W3110, DH10B and BL21-DE3. The efficiency of the integration into the E. coli chromosome and the expression of the introduced genetic circuit at the investigated loci varied significantly. The integrations did not have a negative impact on growth; however, they completely abolished motility. From the investigated E. coli K12 MG1655 flagellar region 1, flgA and flgG are the most suitable chromosomal integration and expression loci.

  4. The SERC K12 Educators Portal to Teaching Activities and Pedagogic Approaches (United States)

    Larsen, K.; Kirk, K. B.; Manduca, C. A.; Ledley, T. S.; Schmitt, L.


    The Science Education Resource Center (SERC) has created a portal to information for K12 educators to provide high-quality grade level appropriate materials from a wide variety of projects and topics. These materials were compiled across the SERC site, showcasing materials that were created for, or easily adaptable to, K12 classrooms. This resource will help support implementation of Next Generation Science Standards by assisting educators in finding innovative resources to address areas of instruction that are conceptually different than previous national and state science standards. Specifically, the K12 portal assists educators in learning about approaches that address the cross-cutting nature of science concepts, increasing students quantitative reasoning and numeracy skills, incorporating technology such as GIS in the classroom, and by assisting educators of all levels of K12 instruction in using relevant and meaningful ways to teach science concepts. The K12 portal supports educators by providing access to hundreds of teaching activities covering a wide array of science topics and grade levels many of which have been rigorously reviewed for pedagogic quality and scientific accuracy. The portal also provides access to web pages that enhance teaching practices that help increase student's system thinking skills, make lectures interactive, assist instructors in conducting safe and effective indoor and outdoor labs, providing support for teaching energy and climate literacy principles, assisting educators in addressing controversial content, provide guidance in engaging students affective domain, and provides a collection of tools for making teaching relevant in 21st century classrooms including using GIS, Google Earth, videos, visualizations and simulations to model and describe scientific concepts. The portal also provides access to material for specific content and audiences by (1) Supporting AGIs 'Map your World' week to specifically highlight teaching

  5. Isolation and Antibiotics Susceptibility Patterns of Escherichia Coli ...

    African Journals Online (AJOL)

    Escherichia coli 0157.H7 were confirmed serologically using latex agglutination kits (OxoidR UK). The isolates were tested for susceptibility to five commonly used antimicrobial agents and plasmid transfer was also carried out using E. coli K12 356 recipient. Out of the 61 non-Sorbitol fermenting (NSF) E. coli isolated from ...

  6. Preparing Teacher Candidates for Virtual Field Placements via an Exposure to K-12 Online Teaching

    Directory of Open Access Journals (Sweden)

    Tian Luo


    Full Text Available Aim/Purpose\tThe goal of this project was to determine what effects exposure to online K-12 teaching and learning activities had on teacher candidates’ perceptions of K-12 online learning, how the exposure allowed teacher candidates to reach greater understanding of online pedagogy, and what effect such exposure had on teacher candidates’ aspirations to complete virtual field experiences. Background\tWith an increasing number of K-12 students learning online within full-time online schools and in blended learning environments, universities must prepare future educators to teach in virtual environments including clinical practice. Before engaging in online field placement, preservice teachers must be oriented to online K-12 teaching and learning. Methodology\tUsing a design-based, mixed-method research methodology, this study drew samples from four sections of a hybrid technology integration course. Preservice teachers’ papers detailing their perceptions, focus groups, and surveys were used to gauge changes in perceptions of online learning after participating in online teaching and learning activities. Contribution\tThe study demonstrated that an exposure to online K-12 classrooms stimulated preservice teachers’ interest in online teaching as they began to feel that online education could be equivalent to traditional education. Findings\tStudents’ perceptions positively improved the equivalency of online learning to traditional schooling, the possibility of positive relationships between teachers and students, and the ability to create interactive learning. Students also reported being more knowledgeable and showed increased interest in participating in virtual field experiences. Future Research\tFuture research may continue to examine if the exposure course, combined with a short-term clinical experiences and long-term online apprenticeships may serve to prepare graduates with the skills necessary to teach in classrooms of the future.

  7. Effect of administration of Streptococcus salivarius K12 on the occurrence of streptococcal pharyngo-tonsillitis, scarlet fever and acute otitis media in 3 years old children. (United States)

    Di Pierro, F; Colombo, M; Giuliani, M G; Danza, M L; Basile, I; Bollani, T; Conti, A M; Zanvit, A; Rottoli, A S


    Streptococcus salivarius K12 (BLIS K12) is a probiotic strain strongly antagonistic to the growth of Streptococcus pyogenes, the most important bacterial cause of pharyngeal infections in humans. Shown to colonize the oral cavity and to be safe for human use, BLIS K12 has previously been reported to reduce pharyngo-tonsillitis episodes in children or adults known to have experienced recurrent streptococcal infection. The present study was focussed upon evaluating the role of BLIS K12 in the control of streptococcal disease and acute otitis media in children attending the first year of kindergarten. By randomization, 222 enrolled children attending the first year of kindergarten were divided into a treated group (N = 111) receiving for 6 months a daily treatment with BLIS K12 (Bactoblis®) and a control group (N = 111) who were monitored as untreated controls. During the 6 months of treatment and 3 months of follow-up, the children were evaluated for treatment tolerance, and for episodes of streptococcal pharyngo-tonsillitis, scarlet fever and acute otitis media. During the 6-month trial (N = 111 per group) the incidence of streptococcal pharyngo-tonsillitis, scarlet fever and acute otitis media was approximately 16%, 9% and 44% respectively in the treated group and 48%, 4% and 80% in the control group. During the 3-months follow-up (N = 29 per group) the corresponding rates of infection were 15%, 0% and 12% in the treated group and 26%, 6% and 36% in the controls. No apparent side effects were detected in the treated group either during treatment or follow-up. All of the enrolled children completed the study. The daily administration of BLIS K12 to children attending their first year of kindergarten was associated with a significant reduction in episodes of streptococcal pharyngitis and acute otitis media. No protection against scarlet fever was detected.

  8. Anxious for Answers: A Meta-Analysis of the E!ects of Anxiety on African American K-12 Students' Mathematics Achievement (United States)

    Young, Jamaal Rashad; Young, Jemimah Lea


    Mathematics anxiety is recognized as a significant performance impediment that affects students across multiple ethnic and economic backgrounds. However, research has yet to fully examine the possible differential effect of mathematics anxiety on underrepresented K-12 students. Specifically, given the long-standing achievement gap between African…

  9. Glucose significantly enhances enterotoxigenic Escherichia coli adherence to intestinal epithelial cells through its effects on heat-labile enterotoxin production.

    Directory of Open Access Journals (Sweden)

    Prageeth Wijemanne

    Full Text Available The present study tested whether exposure of enterotoxigenic Escherichia coli (ETEC to glucose at different concentrations in the media results in increased bacterial adherence to host cells through increased heat-labile enterotoxin (LT production, thereby suggesting the effects are physiological. Porcine-origin ETEC strains grown in Casamino acid yeast extract medium containing different concentrations of glucose were washed and inoculated onto IPEC-J2 porcine intestinal epithelial cells to test for effects on adherence and host cell cAMP concentrations. Consistent with previous studies, all LT+ strains had higher ETEC adherence to IPEC-J2 cells than did LT- strains. Adherence of the LT- but not the LT+ strains was increased by pre-incubating the IPEC-J2 cells with LT and decreased by co-incubation with GM1 ganglioside in a dose-dependent manner (P<0.05. To determine whether the glucose concentration of the cell culture media has an effect on adherence, IPEC-J2 cells were inoculated with LT+ or LT- strains in cell culture media containing a final glucose concentration of 0, 0.25, 0.5, 1.0 or 2.0%, and incubated for 4 h. Only media containing 0.25% glucose resulted in increased adherence and cAMP levels, and this was limited to IPEC-J2 cells inoculated with LT+ strains. This study supports the hypothesis that glucose, at a concentration optimal for LT expression, enhances bacterial adherence through the promotion of LT production. Hence, these results establish the physiological relevance of the effects of glucose on LT production and provide a basis for how glucose intake may influence the severity of ETEC infection.

  10. Saline Lakes: Platforms for Place-Based Scientific Inquiry by K-12 Students (United States)

    Godsey, H. S.; Chapman, D. S.; Hynek, S. A.; Jarrell, E.; Johnson, W. P.; Naftz, D. L.; Neuman, C. R.; Uno, K.


    WEST (Water, the Environment, Science and Teaching) is an NSF-funded GK-12 program at the University of Utah. WEST partners graduate students in the sciences with K-12 teachers to enhance inquiry and place- based science teaching in the Salt Lake City urban area. This region is unique in that habitats relating to the entire local hydrologic cycle are accessible within 30 minutes drive of the city. Great Salt Lake, a large closed-basin lake northwest of the city, generates lake-effect snows that fall on the mountains to the east and serves as the terminal point for rivers and streams that drain over 89,000 km2. The lake's salinity ranges from 14-25% and only a few halophilic species are able to survive in its waters. Despite the low diversity, brine shrimp, brine flies, algae and bacteria are abundant in Great Salt Lake and provide the basis of the food chain for millions of migratory shorebirds and waterfowl that feed in the open water, wetlands and saline flats. WEST has teamed up with researchers from the University of Utah, the USGS, the Utah State Dept. of Environmental Quality, local advocacy groups and a private consulting firm to develop a series of projects that involve K-12 students in an actual research project to study the effects of anthropogenic influences on the lake. The study will produce site-specific water-quality standards to protect the invertebrates, shorebirds, and waterfowl that utilize Great Salt Lake. Students will participate in a research cruise on the lake, collecting samples and data to contribute to an online database that will be shared among participating schools. Students will learn about navigation tools, collect and examine brine shrimp, and measure concentrations of optical brighteners and cyanobacteria as indicators of anthropogenic influences to Great Salt Lake. Parts of the southern arm of the lake are stratified into an upper and lower brine layer and the interface between the two layers can be identified by abrupt changes in

  11. Living in a Materials World: Materials Science Engineering Professional Development for K-12 Educators

    Energy Technology Data Exchange (ETDEWEB)

    Anne Seifert; Louis Nadelson


    Advances in materials science are fundamental to technological developments and have broad societal impacs. For example, a cellular phone is composed of a polymer case, liquid crystal displays, LEDs, silicon chips, Ni-Cd batteries, resistors, capacitors, speakers, microphones all of which have required advances in materials science to be compacted into a phone which is typically smaller than a deck of cards. Like many technological developments, cellular phones have become a ubiquitous part of society, and yet most people know little about the materials science associated with their manufacture. The probable condition of constrained knowledge of materials science was the motivation for developing and offering a 20 hour fourday course called 'Living in a Materials World.' In addition, materials science provides a connection between our every day experiences and the work of scientists and engineers. The course was offered as part of a larger K-12 teacher professional development project and was a component of a week-long summer institute designed specifically for upper elementary and middle school teachers which included 20 hour content strands, and 12 hours of plenary sessions, planning, and collaborative sharing. The focus of the institute was on enhancing teacher content knowledge in STEM, their capacity for teaching using inquiry, their comfort and positive attitudes toward teaching STEM, their knowledge of how people learn, and strategies for integrating STEM throughout the curriculum. In addition to the summer institute the participating teachers were provided with a kit of about $300 worth of materials and equipment to use to implement the content they learned in their classrooms. As part of this professional development project the participants were required to design and implement 5 lesson plans with their students this fall and report on the results, as part of the continuing education course associated with the project. 'Living in a

  12. Issues Related to Technology in Teacher Education Programs and K-12 Public Schools in Texas

    Directory of Open Access Journals (Sweden)

    Jon Denton


    Full Text Available This paper describes the support systems, financial support, current use of technology, and infrastructure issues at selected institutions of higher education (IHE and in K-12 public schools in the State of Texas, United States. Discussion is provided on how current practitioners in public schools and institutions of higher education that prepare pre-service teachers for these schools match regarding technology. In depth discussion is provided on two surveys--one of higher education institutions and one of public schools--along with a discussion of the findings as they relate to the ability of institutions of higher education to support K-12 schools through the preparation of future teachers well equipped to use and comfortable with current and emerging technologies.

  13. Advanced Energy Design Guide K-12: Next Generation of School Design and Operation

    Energy Technology Data Exchange (ETDEWEB)

    Torcellini, Paul A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Pless, Shanti [National Renewable Energy Laboratory (NREL), Golden, CO (United States)


    Driven by energy efficiency advances and renewable energy cost reductions, zero energy buildings are popping up all around the country. Although zero energy represents a bold paradigm shift - from buildings that consume energy to buildings that produce enough energy to meet their energy needs on an annual basis - it isn't a sudden shift. Zero energy buildings are the result of steady, incremental progress by researchers and building professionals working together to improve building energy performance. ASHRAE is taking the lead by publishing - in partnership with the American Institute of Architects (AIA), the Illuminating Engineering Society (IES), the U.S. Green Building Council (USGBC), and the U.S. Department of Energy (DOE) - a new series of advanced energy design guides (AEDGs) focused on zero energy buildings. The recently completed Advanced Energy Design Guide for K-12 School Buildings: Achieving Zero Energy (K-12 ZE AEDG) is the first in this series.

  14. Science achievement as an indicator of educational opportunity available in rural K--12 districts in Texas (United States)

    Capehart, Cheryl Louise

    Purpose of the study. This study examined Rural K--12 Texas districts to investigate whether science achievement could serve as a gauge to measure the availability and quality of rigorous educational opportunities in Rural Texas districts. Procedure. A Case II criterion-group design was used; 2 groups of districts were selected based on their 3-year performances on the 8th grade Science Texas Assessment of Academic Skills (TAAS)---the statewide criterion-referenced test. The High Performing Group (HPG) was composed of 30 top performing districts; the Low Performing Group (LPG) was composed of 30 lowest performing districts. Data collection was limited to archived quantitative data from Texas Education Agency's open records. Achievement variables were percent passing (1) Science TASS, (2) Biology End-of-Course (EoC) test and (3) the composite passing all Reading, Writing, and Mathematics TAAS. Academic variables were percent participating in (1) advanced courses, (2) rigorous graduation programs, and (3) college entrance examinations. District quality indicators also included 3 budget variables: (1) average teacher salary, (2) per pupil instructional expenditure, (3) percent allocated for instructional leadership; and 4 staff variables: (1) percent teachers fully certified, (2) percent teachers with advanced degrees, (3) average years teacher experience, (4) average percent non-turnover of teachers. One score per variable was obtained for each district. The HPG and LPG were compared on each variable using the group means, standard deviations, standard errors of the mean, Levene's test for equality of variance, and a t test for equality of means with a 95% confidence level. The Pearson correlation with two-tailed significance calculated the relationship of each independent variable (budget and staff factors) to each dependent variable (performance measures). Science TASS and a Combined Science score (grand mean of Science TASS & Biology EoC passing rates) were

  15. Graduate students' motivation to teach plant sciences to K-12 audiences


    Welsh, Melissa Leiden


    Graduate students' motivation to share their knowledge and research with K-12 audiences as future scientists is informed by their beliefs and perceived value of science literacy outreach. Graduate training programs in academia integrate outreach teaching components to equip future scientists with a variety of communication skills, which may reflect either a transmission of knowledge to the learner or through engagement with the learner. As such, the education component of the "Partnership for...

  16. Multi-Directional Microaggressions: Filipino Students and Everyday Racism in Hawai`i's K-12 Schools


    Viernes, Kate


    This thesis examines Filipino Americans, Hawai`i's largest Asian Pacific Islander (API) group and their experiences with racism in Hawai`i, specifically in its K-12 educational system. Perceptions of Hawai`i as a model of "multiculturalism" obscure how the state's racially diverse population lives in the condition of settler colonialism which reproduce processes of racialization enabled by the islands' white colonizers. Through Critical Race Theory (CRT), I document how racial microaggression...

  17. CESAME: Providing High Quality Professional Development in Science and Mathematics for K-12 Teachers (United States)

    Hickman, Paul


    It is appropriate that after almost half a century of Science and Mathematics education reform we take a look back and a peek forward to understand the present state of this wonderfully complex system. Each of the components of this system including teaching, professional development, assessment, content and the district K-12 curriculum all need to work together if we hope to provide quality science, mathematics and technology education for ALL students. How do the state and national standards drive the system? How do state policies on student testing and teacher licensure come into play? How do we improve the preparation, retention and job satisfaction of our K-12 teachers? What initiatives have made or are making a difference? What else needs to be done? What can the physics community do to support local efforts? This job is too big for any single organization or individual but we each can contribute to the effort. Our Center at Northeastern University, with support from the National Science Foundation, has a sharply defined focus: to get high quality, research-based instructional materials into the hands of K-12 classroom teachers and provide the support they need to use the materials effectively in their classrooms.

  18. Advanced Energy Retrofit Guide: Practical Ways to Improve Energy Performance, K-12 Schools (Book)

    Energy Technology Data Exchange (ETDEWEB)


    The U.S. Department of Energy developed the Advanced Energy Retrofit Guides (AERGs) to provide specific methodologies, information, and guidance to help energy managers and other stakeholders plan and execute energy efficiency improvements. Detailed technical discussion is fairly limited. Instead, we emphasize actionable information, practical methodologies, diverse case studies, and unbiased evaluations of the most promising retrofit energy efficiency measures for each building type. A series of AERGs is under development, addressing key segments of the commercial building stock. K-12 schools were selected as one of the highest priority building sectors, because schools affect the lives of most Americans. They also represent approximately 8% of the energy use and 10% of the floor area in commercial buildings nationwide. U.S. K-12 school districts spend more than $8 billion each year on energy - more than they spend on computers and textbooks combined. Most occupy older buildings that often have poor operational performance - more than 30% of schools were built before 1960. The average age of a school is about 42 years - which is nearly the expected serviceable lifespan of the building. K-12 schools offer unique opportunities for deep, cost-effective energy efficiency improvements, and this guide provides convenient and practical guidance for exploiting these opportunities in the context of public, private, and parochial schools.

  19. An Early Start in Robotics – K-12 Case-Study

    Directory of Open Access Journals (Sweden)

    Celina Pinto Leão


    Full Text Available

    This paper describes a study carried out with K-12 students. This study is focused on understanding the motivation of these students on the use of robots in the Project Area curricular unit and to understand whether they want to continue their studies in technology areas. K-12 students participated in the RoboParty® event, where the main task is to assemble and program a robot. In other words, the students, in a simple and entertaining way and guided by qualified tutors, learned how to build a robot. At the end of the academic year, a questionnaire was applied to identify and evaluate the K-12 students' opinions regarding the experience. The students’ reaction to this experience as well to the direct contact with the university environment was quite positive.

  20. Using Scientific Visualizations to Enhance Scientific Thinking In K-12 Geoscience Education (United States)

    Robeck, E.


    The same scientific visualizations, animations, and images that are powerful tools for geoscientists can serve an important role in K-12 geoscience education by encouraging students to communicate in ways that help them develop habits of thought that are similar to those used by scientists. Resources such as those created by NASA's Scientific Visualization Studio (SVS), which are intended to inform researchers and the public about NASA missions, can be used in classrooms to promote thoughtful, engaged learning. Instructional materials that make use of those visualizations have been developed and are being used in K-12 classrooms in ways that demonstrate the vitality of the geosciences. For example, the Center for Geoscience and Society at the American Geosciences Institute (AGI) helped to develop a publication that outlines an inquiry-based approach to introducing students to the interpretation of scientific visualizations, even when they have had little to no prior experience with such media. To facilitate these uses, the SVS team worked with Center staff and others to adapt the visualizations, primarily by removing most of the labels and annotations. Engaging with these visually compelling resources serves as an invitation for students to ask questions, interpret data, draw conclusions, and make use of other processes that are key components of scientific thought. This presentation will share specific resources for K-12 teaching (all of which are available online, from NASA, and/or from AGI), as well as the instructional principles that they incorporate.

  1. Opinions on computing education in Korean K-12 system: higher education perspective (United States)

    Kim, Dae-Kyoo; Jeong, Dongwon; Lu, Lunjin; Debnath, Debatosh; Ming, Hua


    The need for computing education in the K-12 curriculum has grown globally. The Republic of Korea is not an exception. In response to the need, the Korean Ministry of Education has announced an outline for software-centric computing education in the K-12 system, which aims at enhancing the current computing education with software emphasis. In this paper, we review the outline from a higher education perspective and provide insights into its constructive improvement based on our experience in computer science education in higher education and a study of global initiatives on computing education. We also consider the social environment for computing education in Korea. In the proposed implementation, we first discuss goals for software-centric computing education and identify areas of focus. The identified areas are discussed in terms of topics to be covered and appropriate exposure of knowledge depth in the three levels in the Korean K-12 system. We then discuss necessary preparations for the success of the plan from academic, governmental and social perspectives.

  2. Novel detection of post-translational modifications in human monocyte-derived dendritic cells after chronic alcohol exposure: Role of inflammation regulator H4K12ac. (United States)

    Parira, Tiyash; Figueroa, Gloria; Laverde, Alejandra; Casteleiro, Gianna; Gomez Hernandez, Mario E; Fernandez-Lima, Francisco; Agudelo, Marisela


    Previous reports on epigenetic mechanisms involved in alcohol abuse have focus on hepatic and neuronal regions, leaving the immune system and specifically monocyte-derived dendritic cells (MDDCs) understudied. Our lab has previously shown histone deacetylases are modulated in cells derived from alcohol users and after in vitro acute alcohol treatment of human MDDCs. In the current study, we developed a novel screening tool using matrix assisted laser desorption ionization-fourier transform-ion cyclotron resonance mass spectrometry (MALDI-FT-ICR MS) and single cell imaging flow cytometry to detect post-translational modifications (PTMs) in human MDDCs due to chronic alcohol exposure. Our results demonstrate, for the first time, in vitro chronic alcohol exposure of MDDCs modulates H3 and H4 and induces a significant increase in acetylation at H4K12 (H4K12ac). Moreover, the Tip60/HAT inhibitor, NU9056, was able to block EtOH-induced H4K12ac, enhancing the effect of EtOH on IL-15, RANTES, TGF-β1, and TNF-α cytokines while restoring MCP-2 levels, suggesting that H4K12ac may be playing a major role during inflammation and may serve as an inflammation regulator or a cellular stress response mechanism under chronic alcohol conditions.

  3. Evaluation of Experiential Outdoor Research Locations in Asia for a K-12 school in Hong Kong (United States)

    Ibarra, D. L.; Joyce, S.


    A team of faculty and administrators from The Independent Schools Foundation Academy spend the 2015 - 2016 academic year identifying possible locations in Asia for a year-round outdoor education center. ISF Academy currently has over 1500 students its K-12 bilingual school in Hong Kong, China. The outdoor education center is an extension of the built campus in Pokfulam and will provide students opportunities to live in a natural setting, participate in outdoor educational activities and study in an environment significantly different than a classroom. Currently ISF Academy students in grades 4 - 12 are off campus twice during the academic year in an experiential learning environment. These current programs include camping, hiking, kayaking, other adventurous activities and service learning opportunities. The purpose of the dedicated site is to have a "home base" for ISF Academy and the experiential learning programs. This past year we looked specifically at programs and locations that could also be used by students for ecology and earth systems based research in the senior school (grades 9 - 12). We have looked at sites in Hong Kong, Indonesia, Malaysia and Taiwan. The ideal site will have marine, terrestrial and mangrove ecosystems and allow students to set up long-term research sites in any of these ecosystems. Creating opportunities for authentic research that allows students spend an extended time in a research setting will help them to gain both skills and independence needed in the future at the tertiary level. The evaluation of these sites included identifying potential research partners, site preparation, logistics in and out of the locations, and the heath/safety management of students living and working in a remote location. In parallel to the site evaluations, the curriculum is being developed for the students that is age and skill appropriate using the frame work of the existing guided discovery curriculum in the primary school, and the MYP and DP

  4. E. coli (United States)

    Liang, Xiao; Liao, Chunyu; Thompson, Michael L; Soupir, Michelle L; Jarboe, Laura R; Dixon, Philip M


    The importance of E. coli as an indicator organism in fresh water has led to numerous studies focusing on cell properties and transport behavior. However, previous studies have been unable to assess if differences in E. coli cell surface properties and genomic variation are associated with different environmental habitats. In this study, we investigated the variation in characteristics of E. coli obtained from stream water and stream bottom sediments. Cell properties were measured for 77 genomically different E. coli strains (44 strains isolated from sediments and 33 strains isolated from water) under common stream conditions in the Upper Midwestern United States: pH 8.0, ionic strength 10 mM and 22°C. Measured cell properties include hydrophobicity, zeta potential, net charge, total acidity, and extracellular polymeric substance (EPS) composition. Our results indicate that stream sediment E. coli had significantly greater hydrophobicity, greater EPS protein content and EPS sugar content, less negative net charge, and higher point of zero charge than stream water E. coli . A significant positive correlation was observed between hydrophobicity and EPS protein for stream sediment E. coli but not for stream water E. coli . Additionally, E. coli surviving in the same habitat tended to have significantly larger (GTG) 5 genome similarity. After accounting for the intrinsic impact from the genome, environmental habitat was determined to be a factor influencing some cell surface properties, such as hydrophobicity. The diversity of cell properties and its resulting impact on particle interactions should be considered for environmental fate and transport modeling of aquatic indicator organisms such as E. coli .

  5. Characterization of high-level expression and sequencing of the Escherichia coli K-12 cynS gene encoding cyanase.


    Sung, Y C; Anderson, P M; Fuchs, J A


    Restriction fragments containing the gene encoding cyanase, cynS, without its transcriptional regulatory sequences were placed downstream of lac and tac promoters in various pUC derivatives to maximize production of cyanase. Plasmid pSJ105, which contains the cynS gene and an upstream open reading frame, gave the highest expression of cyanase. Approximately 50% of the total soluble protein in stationary-phase cultures of a lac-deleted strain containing plasmid pSJ105 was cyanase. The inserted...

  6. Evaluation of beta-lactose, PVP K12 and PVP K90 as excipients to prepare piroxicam granules using two wet granulation techniques. (United States)

    Albertini, Beatrice; Cavallari, Cristina; Passerini, Nadia; González-Rodríguez, M L; Rodriguez, Lorenzo


    The present investigation aimed at evaluating the use of different excipients, beta-lactose and polyvinylpyrrolidone of two molecular weights (PVP K12 and PVP K90), in the production of improved release piroxicam granules, by wet granulation using both water and steam as granulation liquid. The formulations examined were: piroxicam (Px)/beta-lactose; Px/PVP K12 and Px/PVP K90, each one at a 1:9 weight ratio. The most significant difference between beta-lactose and PVP is that, using the first excipient, both steam and water granules were produced while, when PVP were employed, only steam granules were obtained. Image analysis revealed that beta-lactose steam granules had a larger surface area with respect to water granules, whereas lower values of this parameter were observed in PVP-s granules, confirming the Scanning Electron Microscopy micrographs and the fractal analysis results. As regards the enhancement of the dissolution profiles, the best result was obtained using beta-lactose steam granules followed by PVP K12 ones, even if the reactive dimension values indicated that during the dissolution process PVP K12 granules modified the surface more than beta-lactose granules. As regards PVP K90, this excipient was the one less influencing the granule morphology and the dissolution behaviour. Differential Scanning Calorimetry analysis suggested the partial amorphisation of the drug in the granules containing the three excipients. This result was then confirmed by X-ray powder diffraction analysis. Therefore, beta-lactose and PVP K12 could be proposed as useful excipients to enhance the dissolution rate of Px from granules prepared using the steam granulation technique.

  7. A Tale of Two Countries: Successes and Challenges in K-12 Computer Science Education in Israel and the United States (United States)

    Gal-Ezer, Judith; Stephenson, Chris


    This article tells a story of K-12 computer science in two different countries. These two countries differ profoundly in culture, language, government and state structure, and in their education systems. Despite these differences, however, they share the pursuit of excellence and high standards in K-12 education. In Israel, curriculum is…

  8. One-to-One Technology in K-12 Classrooms: A Review of the Literature from 2004 through 2014 (United States)

    Harper, Ben; Milman, Natalie B.


    This literature review examined empirical research conducted between 2004 and 2014 regarding 1:1 technologies in K-12 educational settings. Our overarching research question was: What does research tell us about 1:1 technology in K-12 classrooms? We used the constant-comparative method to analyze, code, and induce themes from 46 relevant articles.…

  9. K-12 Students' Perceptions of Scientists: Finding a Valid Measurement and Exploring Whether Exposure to Scientists Makes an Impact (United States)

    Hillman, Susan J.; Bloodsworth, Kylie H.; Tilburg, Charles E.; Zeeman, Stephan I.; List, Henrietta E.


    This study was launched from a National Science Foundation GK-12 grant in which graduate fellows in Science, Technology, Engineering, and Mathematics (STEM) are placed in classrooms to engage K-12 students in STEM activities. The investigation explored whether the STEM Fellows' presence impacted the K-12 students' stereotypical image of a…

  10. Multi-omics Quantification of Species Variation of Escherichia coli Links Molecular Features with Strain Phenotypes

    DEFF Research Database (Denmark)

    Monk, Jonathan M; Koza, Anna; Campodonico, Miguel A


    Escherichia coli strains are widely used in academic research and biotechnology. New technologies for quantifying strain-specific differences and their underlying contributing factors promise greater understanding of how these differences significantly impact physiology, synthetic biology......, metabolic engineering, and process design. Here, we quantified strain-specific differences in seven widely used strains of E. coli (BL21, C, Crooks, DH5a, K-12 MG1655, K-12 W3110, and W) using genomics, phenomics, transcriptomics, and genome-scale modeling. Metabolic physiology and gene expression varied...... widely with downstream implications for productivity, product yield, and titer. These differences could be linked to differential regulatory structure. Analyzing high-flux reactions and expression of encoding genes resulted in a correlated and quantitative link between these sets, with strain...

  11. Listening to the soloists in the choir: A study of the life experience of exemplary K--12 environmental educators (United States)

    Carter, Robert L.

    Following the environmental awakening of the last third of the twentieth century, anchored by the enactment of the National Environmental Policy Act of 1969, education, and its frontline providers---teachers---were expected to become the dominant engines for realizing the new ideal of an environmentally literate populace. In reality, no such change has yet occurred despite continuous efforts from a variety of governmental and nongovernmental entities. A review of the literature revealed that there was something missing in research on the preparation of teachers for environmental education. There did not appear to be any research into why teachers who embrace the idea of environmental education as a fundamental part of education do so in the first place. In this study, described as basic qualitative research, I used a multiple-session interview technique to explore, in depth, the life experiences of the phenomenon I refer to as "an exemplary K-12 environmental educator." The pool of potential participants was composed of environmental education award winners from several states in the upper Midwest. Ten teachers were recruited from the available pool. Among these 10 were represented both genders, teaching in grades ranging from grade 2 through grade 12. The results of this study provide a look into a complex set of interactions which were eventually manifested as the phenomenon of interest. Highlights of the findings indicate that (1) a strong connection to the environment was developed early in life, (2) this connection was the result of experiences shared in the outdoors with significant others, (3) a love of learning and self-directedness are both integral to who these individuals are, (4) the study participants, as K-12 educators, draw heavily from the support of relevant professional associations. Implications for the continuing professional education of teachers in environmental education are that more emphasis is needed on awareness and affect as components

  12. Making NASA Earth Observing System Satellite Data Accessible to the K-12 and Citizen Scientist Communities (United States)

    Moore, Susan W.; Phelps, Carrie S.; Chambers, Lin H.


    The Atmospheric Sciences Data Center (ASDC) at NASA s Langley Research Center houses over 700 data sets related to Earth s radiation budget, clouds, aerosols and tropospheric chemistry. These data sets are produced to increase academic understanding of the natural and anthropogenic perturbations that influence global climate change. The Mentoring and inquirY using NASA Data on Atmospheric and earth science for Teachers and Amateurs (MY NASA DATA) project has been established to systematically support educational activities at all levels of formal and informal education by reducing these large data holdings to microsets that will be easily explored and understood by the K-12 and the amateur scientist communities

  13. Sustaining K-12 professional development in geology: Recurrent participation in Rockcamp (United States)

    Repine, T.E.; Hemler, D.A.; Behling, R.E.


    A reconnaissance study of the geology professional development program known as RockCamp was initiated to examine the sustained, or recurrent, participation of K-12 science teachers. Open-ended interviews, concept mapping, and creative writing assignments were used to explore the perceptions of six teachers possessing an exceptional record of participation. Efficacy, fun, right time of life, and support emerged as unanimous reasons for recurrent participation. Content, friendship, and methodology were very important. College credit was not critical. These teachers' perceptions suggest their sustained involvement in the RockCamp Program is stimulated by situated learning experiences stressing a compare, contrast, connect, and construct pedagogy within a supportive learning community.

  14. Educating K-12 Professionals and Parents: Finding Health Information for Special Needs Children. (United States)

    Irish, D Elizabeth; Lyman, Deborah M; Squillace, Helen A; Geyer, Enid M; Cosgrove, Tammy D; Hagzan, Amanda; Leinung, Jill; Tosh, Traci


    A successful partnership model between an academic health sciences library and a K-12 school district to provide librarians, nurses, and special education staff with access to health information to support special needs children and their parents is presented. Train-the-trainer staff sessions and a parent session were collaboratively developed. Funding support was used to purchase iPads for librarians and nurses to deliver mobile support. The results indicate the resources taught are being used to find health information and the school librarians and nurses are being sought after to assist in finding health information. Positive feedback from the school district indicates this model could be replicated in similar settings.

  15. Restructuring the relationship between STEM faculty and K-12: crafting a figured world of partnership (United States)

    Fayez, Merfat


    Over the past 50 years, identity has provided us with a dynamic tool to understand and examine how people are constituted as agents as well as subjects of culturally constructed, socially enacted worlds. Pertinent to this conceptualization, Skerrett and Sevian focus on science and mathematics faculty's identities and seek to understand how certain aspects of their identities mediate certain motivations to involvement in K-12 service. While I believe that the authors presented an affluent discussion of agency from the perspective of identity, I think that if we are to understand agency from a sociocultural perspective, we have to magnify a view of identity and agency in the figured world of practice/activity. My main goal is not only to reclaim the importance of the individual dimension and agency within a profoundly social view of the self, but also to highlight the figured contextual factors that would either enable or constrain STEM faculty's involvement in K-12 outreach. After first outlining the perspective of identity and agency that was adopted by Skerrett and Sevian, I extend the discussion of Skerrett and Sevian to move forward toward a figured world of partnership. I conclude by positing that the third generation of activity theory has a potential for contributing to our understanding of how the social institutional context and its structure is important to our understanding of individual agency.

  16. Pay It Forward: Teacher Candidates’ Use of Historical Artifacts to Invigorate K-12 History Instruction

    Directory of Open Access Journals (Sweden)

    Scott M. Waring,


    Full Text Available The history education literature is replete with a call to help teachers understand that history should be taught as being inquiry-based and interpretive. We are encouraged, and rightfully so, to do history, to perform history, to do democracy, and to motivate students for inquiry and action by using primary sources. The authors developed a unit of study for history and social studies teacher candidates that would address several issues: (a motivate and inspire future teachers to use inquiry as a tool to build K-12 students’ historical understanding and facilitate purposeful utilization of artifacts with ease; (b help future teachers increase their knowledge of local history; and (c present a unit that could be easily used in a secondary history course and, with some modifications, could be adapted for elementary and middle school history classrooms. The assignment was named Pay it Forward: Invigorating Instruction through Local History. This multifaceted assignment included the development of a lesson plan that would (a demonstrate a robust understanding of engaging students in historical inquiry and local history, and (b focus on an artifact that the teacher candidate would find as part of the investigation. The majority of the teacher candidates in this study did show evidence of, albeit limited at times, designing curriculum that encouraged K-12 students to engage in historical inquiry. Making the bridge between theory and practice, or showing evidence of learning from the methods courses, was clearly evident across the lesson plans.

  17. Implications of the Next Generation Science Standards for K-12, EPO, and Higher Education (United States)

    Schultz, G.; Barber, J.; Pomeroy, R.; Reagan, G.


    The newly-released Next Generation Science Standards (NGSS) have been under development for a few years with broad community input and explicit involvement of many states likely to adopt these as their own science standards. Several key features of the NGSS make these a substantial advance from the existing National Science Education Standards (NRC 1996), including focus on three dimensions previously outlined in A Framework for K-12 Science Education (NRC 2011): Science and Engineering Practices; Cross-cutting Concepts; and Disciplinary Core Ideas. What are the implications of all this now for K-12 educators, in the immediate term and in the long-term? What do the NGSS imply for EPO professionals, especially those involved in science curriculum development and teacher professional development? What should higher education faculty know about the NGSS, especially as it relates to the preparation of incoming college students, as well as the education of future elementary and secondary science teachers in college (including in Astro 101-type courses)?

  18. simUfish: An Interactive Application to Teach K-12 Students About Zebrafish Behavior. (United States)

    Mwaffo, Violet; Korneyeva, Veronika; Porfiri, Maurizio


    As the zebrafish is rapidly becoming a species of choice in preclinical research, several efforts are being placed toward creating educational programs for K-12 students based on this promising model organism. However, as any other model organisms, the use of zebrafish in classroom settings requires additional experimental resources and poses ethical challenges related to animal use. To mitigate these factors, we have developed an application (app), simUfish, which implements a mathematical model of zebrafish behavior for generating multiple fish trajectories and animating their body undulations. simUfish is developed using a multiplatform game engine and is expected to promote the knowledge of zebrafish behavior to both K-12 students and the general public. Specifically, it demonstrates basic principles of fish individual and social behaviors, including environment interaction; fear response toward a predator; shoaling; and attraction toward a stimulus, which can be a food source or simply a finger placed on the touch screen. The effectiveness of the app as an accessible experimental tool for learning was tested in an outreach activity on middle school students from the New York City school system. The results from this activity show an immediate, tangible improvement of students' satisfaction and willingness to learn about key concepts on zebrafish behavior, accompanied by high level of interest in life sciences.

  19. Technical Support Document: Development of the Advanced Energy Design Guide for K-12 Schools--30% Energy Savings

    Energy Technology Data Exchange (ETDEWEB)

    Pless, S.; Torcellini, P.; Long, N.


    This Technical Support Document describes the process and methodology for the development of the Advanced Energy Design Guide for K-12 School Buildings (K-12 AEDG), a design guidance document intended to provide recommendations for achieving 30% energy savings in K-12 Schools over levels contained in ANSI/ASHRAE/IESNA Standard 90.1-1999, Energy Standard for Buildings Except Low-Rise Residential Buildings. The 30% energy savings target is the first step toward achieving net-zero energy schools; schools that, on an annual basis, draw from outside sources less or equal energy than they generate on site from renewable energy sources.

  20. A Groundwater project for K-12 schools: Bringing research into the classroom (United States)

    Rodak, C. M.; Walsh, M.; Gensic, J.


    Simple water quality test kits were used in a series of K-12 classrooms to demonstrate scientific processes and to motivate learning in K-12 students. While focused on student learning, this project also allowed collection of regional data on groundwater quality (primarily nitrate) in the study area. The project consisted of development and administration of a weeklong groundwater quality unit introduced to K-12 schools in northern Indiana and taught by a graduate student in an engineering discipline. The structure of the week started with an introduction to basic groundwater concepts modified for the specific grade level; for this project the students ranged from grades 4-12. In addition to groundwater basics, the purpose of the collection of the water quality data, as well as relevance to the research of the graduate student, were outlined. The students were then: (i) introduced to two simple water quality testing methods for nitrates, (ii) required to hypothesize as to which method will likely be "better" in application, and (iii) asked to practice using these two methods under laboratory conditions. Following practice, the students were asked to discuss their hypotheses relative to what was observed during the practice focusing on which testing method was more accurate and/or precise. The students were then encouraged to bring water samples from their home water system (many of which are on private wells) to analyze within groups. At the end of the week, the students shared their experience in this educational effort, as well as the resulting nitrate data from numerous groundwater wells (as collected by the students). Following these discussions the data were added to an online database housed on a wiki sponsored by the Notre Dame Extended Research Community ( These data were plotted using the free service MapAList to visually demonstrate to the students the spatial distribution of the data and how their results have

  1. Achieving 50% Energy Savings in New Schools, Advanced Energy Design Guides: K-12 Schools (Brochure)

    Energy Technology Data Exchange (ETDEWEB)


    This fact sheet summarizes recommendations for designing elementary, middle, and high school buildings that will result in 50% less energy use than conventional new schools built to minimum code requirements. The recommendations are drawn from the Advanced Energy Design Guide for K-12 School Buildings, an ASHRAE publication that provides comprehensive recommendations for designing low-energy-use school buildings (see sidebar). Designed as a stand-alone document, this fact sheet provides key principles and a set of prescriptive design recommendations appropriate for smaller schools with insufficient budgets to fully implement best practices for integrated design and optimized performance. The recommendations have undergone a thorough analysis and review process through ASHRAE, and have been deemed the best combination of measures to achieve 50% savings in the greatest number of schools.


    Directory of Open Access Journals (Sweden)

    Chris INMAN


    Full Text Available This study reviewed empirical research conducted in Second Life by educators since Second Life’s launch in 2003. The study’s purpose was to identify how Second Life is being used in both K-12 and higher education. The methodology, findings, and recommendations of 27 research studies were analyzed. Researchers identified potential problems when using Second Life in education, including issues with the Second Life software and hardware requirements, a steep learning curve, and the possibility of students becoming exposed to distractions or inappropriate content. Researchers discussed potential uses of Second Life including role-play, game and simulation creation, implementation within distance education programs, and the ability to encourage student-centered learning activities. Analysis also revealed several recommendations for educators intending to use Second Life.

  3. Project BioEYES: Accessible Student-Driven Science for K-12 Students and Teachers. (United States)

    Shuda, Jamie R; Butler, Valerie G; Vary, Robert; Farber, Steven A


    BioEYES, a nonprofit outreach program using zebrafish to excite and educate K-12 students about science and how to think and act like scientists, has been integrated into hundreds of under-resourced schools since 2002. During the week-long experiments, students raise zebrafish embryos to learn principles of development and genetics. We have analyzed 19,463 participating students' pre- and post-tests within the program to examine their learning growth and attitude changes towards science. We found that at all grade levels, BioEYES effectively increased students' content knowledge and produced favorable shifts in students' attitudes about science. These outcomes were especially pronounced in younger students. Having served over 100,000 students, we find that our method for providing student-centered experiences and developing long-term partnerships with teachers is essential for the growth and sustainability of outreach and school collaborations.

  4. A Mixed-Method Approach on Digital Educational Games for K12: Gender, Attitudes and Performance (United States)

    Law, Effie Lai-Chong; Gamble, Tim; Schwarz, Daniel; Kickmeier-Rust, Michael D.; Holzinger, Andreas

    Research on the influence of gender on attitudes towards and performance in digital educational games (DEGs) has quite a long history. Generally, males tend to play such games more engagingly than females, consequently attitude and performance of males using DEGs should be presumably higher than that of females. This paper reports an investigation of a DEG, which was developed to enhance the acquisition of geographical knowledge, carried out on British, German and Austrian K12 students aged between 11 and 14. Methods include a survey on initial design concepts, user tests on the system and two single-gender focus groups. Gender and cultural differences in gameplay habit, game type preferences and game character perceptions were observed. The results showed that both genders similarly improved their geographical knowledge, although boys tended to have a higher level of positive user experience than the girls. The qualitative data from the focus groups illustrated some interesting gender differences in perceiving various aspects of the game.

  5. A Scientist's Guide to Achieving Broader Impacts through K-12 STEM Collaboration. (United States)

    Komoroske, Lisa M; Hameed, Sarah O; Szoboszlai, Amber I; Newsom, Amanda J; Williams, Susan L


    The National Science Foundation and other funding agencies are increasingly requiring broader impacts in grant applications to encourage US scientists to contribute to science education and society. Concurrently, national science education standards are using more inquiry-based learning (IBL) to increase students' capacity for abstract, conceptual thinking applicable to real-world problems. Scientists are particularly well suited to engage in broader impacts via science inquiry outreach, because scientific research is inherently an inquiry-based process. We provide a practical guide to help scientists overcome obstacles that inhibit their engagement in K-12 IBL outreach and to attain the accrued benefits. Strategies to overcome these challenges include scaling outreach projects to the time available, building collaborations in which scientists' research overlaps with curriculum, employing backward planning to target specific learning objectives, encouraging scientists to share their passion, as well as their expertise with students, and transforming institutional incentives to support scientists engaging in educational outreach.

  6. Crowd-Sourcing with K-12 citizen scientists: The Continuing Evolution of the GLOBE Program (United States)

    Murphy, T.; Wegner, K.; Andersen, T. J.


    Twenty years ago, the Internet was still in its infancy, citizen science was a relatively unknown term, and the idea of a global citizen science database was unheard of. Then the Global Learning and Observations to Benefit the Environment (GLOBE) Program was proposed and this all changed. GLOBE was one of the first K-12 citizen science programs on a global scale. An initial large scale ramp-up of the program was followed by the establishment of a network of partners in countries and within the U.S. Now in the 21st century, the program has over 50 protocols in atmosphere, biosphere, hydrosphere and pedosphere, almost 140 million measurements in the database, a visualization system, collaborations with NASA satellite mission scientists (GPM, SMAP) and other scientists, as well as research projects by GLOBE students. As technology changed over the past two decades, it was integrated into the program's outreach efforts to existing and new members with the result that the program now has a strong social media presence. In 2016, a new app was launched which opened up GLOBE and data entry to citizen scientists of all ages. The app is aimed at fresh audiences, beyond the traditional GLOBE K-12 community. Groups targeted included: scouting organizations, museums, 4H, science learning centers, retirement communities, etc. to broaden participation in the program and increase the number of data available to students and scientists. Through the 20 years of GLOBE, lessons have been learned about changing the management of this type of large-scale program, the use of technology to enhance and improve the experience for members, and increasing community involvement in the program.

  7. Educational Technology: A Review of the Integration, Resources, and Effectiveness of Technology in K-12 Classrooms

    Directory of Open Access Journals (Sweden)

    Adolph Delgado


    Full Text Available There is no questioning that the way people live, interact, communicate, and conduct business is undergoing a profound, rapid change. This change is often referred to as the “digital revolution,” which is the advancement of technology from analog, electronic and mechanical tools to the digital tools available today. Moreover, technology has begun to change education, affecting how students acquire the skill sets needed to prepare for college and a career and how educators integrate digital technological instructional strategies to teach. Numerous studies have been published discussing the barriers of integrating technology, the estimated amount of investment that is needed in order to fully support educational technology, and, of course, the effectiveness of technology in the classroom. As such, this article presents a critical review of the transitions that technology integration has made over the years; the amount of resources and funding that has been allocated to immerse school with technology; and the conflicting results presented on effectiveness of using is technology in education. Through synthesis of selected themes, we found a plethora of technological instructional strategies being used to integrate technology into K-12 classrooms. Also, though there have been large investments made to integrate technology into K-12 classrooms to equip students with the skills needed to prepare for college and a career, the practical use of this investment has not been impressive. Lastly, several meta-analyses showed promising results of effectiveness of technology in the classroom. However, several inherent methodological and study design issues dampen the amount of variance that technology accounts for.

  8. Marshalling Corporate Resources for Public and K-12 Technical Education Outreach and Engagement (United States)

    Wynne, James


    In 1988, the Education Task Force of the Business Roundtable recommended that American corporations invest in pre-college education. Prior to that date, corporate investment was targeted at higher education. IBM and other corporations responded by encouraging their employees and their corporate philanthropic organizations to develop programs aimed at enhancing pre-college education. The IBM TJ Watson Research Center initiated a Local Education Outreach program, active for these past 23 years, that marshals the resources of our science-rich institution to enhance STEM education in our local schools. We have broad and deep partnerships between the Research Center and local school districts, including New York City. We have just completed our 19th consecutive year of Family Science Saturdays, which brings 4th and 5th grade children, along with their parents, to our Research Center for hands-on workshops in topics like States of Matter, Polymer Science, Kitchen Chemistry, and Sound and Light. The workshops are staffed by IBM volunteers, assisted by local high school student ``Peer Teachers.'' Since 1990, the IBM Corporation has joined with a coalition of other companies, professional engineering societies, and government agencies to sponsor the annual Engineers Week (EWeek) campaign of technical education outreach, serving as Corporate Chair in 1992, 2001, and 2008. In recent years, we have annually recruited around 5000 IBM volunteers to reach out to more than 200,000 K-12 students in order to increase their awareness and appreciation of technical careers and encourage them to continue their studies of STEM (science, technology, engineering, and mathematics). The speaker, who helped found the APS Forum on Education (FED) and served as FED Councillor for 8 years, will review these and other programs for Public and K-12 Technical Education Outreach and Engagement.

  9. The Virtual Scientist: connecting university scientists to the K-12 classroom through videoconferencing. (United States)

    McCombs, Glenn B; Ufnar, Jennifer A; Shepherd, Virginia L


    The Vanderbilt University Center for Science Outreach (CSO) connects university scientists to the K-12 community to enhance and improve science education. The Virtual Scientist program utilizes interactive videoconference (IVC) to facilitate this connection, providing 40-50 sessions per academic year to a national audience. Scientists, defined as research faculty members, clinicians, postdoctoral fellows, graduate and medical students, and professional staff, participate through conventional volunteer recruitment and program announcements as well as outreach partnership efforts with other Vanderbilt centers. These experts present 30- to 45-min long, grade-appropriate content sessions from the CSO IVC studio or their own laboratory. Teachers register for sessions via an on-line application process. After the session, teachers, students, and experts are requested to complete an anonymous on-line evaluation that addresses both technical- and content-associated issues. Results from 2003 to the present indicated a favorable assessment for a promising program. Results showed that 69% of students (n = 335) and 88% of teachers (n = 111) felt that IVC improved access to scientists, whereas 97% of students (n = 382) and teachers (n = 126) and 100% of scientists (n = 23) indicated that they would participate in future videoconferences. Students and teachers considered that the Virtual Scientist program was effective [76% (n = 381) and 89% (n = 127), respectively]. In addition, experts supported IVC as effective in teaching [87% (n = 23)]. Because of the favorable responses from experts, teachers, and students, the CSO will continue to implement IVC as a tool to foster interactions of scientists with K-12 classrooms.

  10. Mars Curriculum for K-12 Science Education, 2nd Edition, Making Tracks on Mars Teacher Resource and Activity Guide (United States)

    Aubele, J. C.; Stanley, J.; Grochowski, A.; Jones, K.; Aragon, J.


    A Mars K-12 curriculum, created by the New Mexico Museum of Natural History & Science, is now in 2nd edition DVD, approved by NASA educational review, 508 compliant to ensure accessibility for people with disabilities, and applicable to MSL.

  11. K-12 science education reform will take a decade, and community partnerships hold best hope for success

    Energy Technology Data Exchange (ETDEWEB)

    Keever, J.R.


    Fundamental change in K-12 science education in the United States, essential for full citizenship in an increasingly technological world, will take a decade or more to accomplish, and only the sustained, cooperative efforts of people in their own communities -- scientists, teachers, and concerned citizens -- will likely ensure success. These were among the themes at Sigma Xi`s national K-12 science education forum.

  12. Real-time footprinting of DNA in the first kinetically significant intermediate in open complex formation by Escherichia coli RNA polymerase. (United States)

    Davis, Caroline A; Bingman, Craig A; Landick, Robert; Record, M Thomas; Saecker, Ruth M


    The architecture of cellular RNA polymerases (RNAPs) dictates that transcription can begin only after promoter DNA bends into a deep channel and the start site nucleotide (+1) binds in the active site located on the channel floor. Formation of this transcriptionally competent "open" complex (RP(o)) by Escherichia coli RNAP at the lambdaP(R) promoter is greatly accelerated by DNA upstream of base pair -47 (with respect to +1). Here we report real-time hydroxyl radical (*OH) and potassium permanganate (KMnO4) footprints obtained under conditions selected for optimal characterization of the first kinetically significant intermediate (I(1)) in RP(o) formation. .OH footprints reveal that the DNA backbone from -71 to -81 is engulfed by RNAP in I(1) but not in RP(o); downstream protection extends to approximately +20 in both complexes. KMnO4 footprinting detects solvent-accessible thymine bases in RP(o), but not in I(1). We conclude that upstream DNA wraps more extensively on RNAP in I(1) than in RP(o) and that downstream DNA (-11 to +20) occupies the active-site channel in I(1) but is not yet melted. Mapping of the footprinting data onto available x-ray structures provides a detailed model of a kinetic intermediate in bacterial transcription initiation and suggests how transient contacts with upstream DNA in I(1) might rearrange the channel to favor entry of downstream duplex DNA.

  13. A Historical Perspective on the Epistemology of K-12 Music Education: An Analysis of Musical Knowledge from the Journals Revista da ABEM and ANPPOM’s Revista OPUS

    Directory of Open Access Journals (Sweden)

    Thaís Lobosque Aquino


    Full Text Available As part of a doctoral thesis based on a theoretical investigation of musical knowledge at Brazilian K-12 schools (AQUINO, 2016, this paper seeks to examine the historical perspective of the epistemology of music education by means of a bibliographical content analysis (FREIRE, 2010 with reference to the role of scholars in building modes of thought on K-12 music education through articles published by two of the most representative journals in the field, the Revista da ABEM and ANPPOM’s Revista OPUS . This study also includes semi-structured interviews (MANZINI, 2004 with the respective presidents of the Brazilian Association of Music Education (ABEM and the National Association of Research and Post-Graduate Studies in Music (ANPPOM. The finding of epistemological weakness in regards to K-12 music education in the periodicals analyzed, far from leading to a posture of conformity, has the potential to inspire music education towards active self-reflection, in order to leverage the delineation of increasingly significant epistemological postulates.

  14. Differentiating enteric Escherichia coli from environmental bacteria through the putative glucosyltransferase gene (ycjM). (United States)

    Deng, Daiyong; Zhang, Ning; Mustapha, Azlin; Xu, Dong; Wuliji, Tumen; Farley, Mary; Yang, John; Hua, Bin; Liu, Fengjing; Zheng, Guolu


    This study is to tackle the challenge posed by the "naturalized" Escherichia coli population against the worldwide practice of E. coli-based water quality monitoring. In the literature, the putative glucosyltransferase gene (ycjM) of E. coli has been identified in silico to be one of the 114 genes specific to enteric E. coli. Based on the sequence of E. coli K-12 MG1655, a PCR assay (ycjPCR) targeting ycjM was developed in this study. As demonstrated by the ycjPCR assay using 367 E. coli strains isolated from animal feces, 97.2% of the isolates carried the ycjM with variations from 93.9% to 100% among nine different host sources, but none of the 17 strains of non-E. coli bacteria and only 23.0% of the environment-isolated cryptic Escherichia strains contained the ycjM. These data experimentally confirmed ycjM to be enteric specific. Our study also showed that the ycjPCR assay was superior to the commonly used tuf- or uidA-based PCR methods in differentiating enteric E. coli from ß-D-glucuronidase-positive environmental bacteria. Furthermore, study on 190 E. coli isolates from water samples, using EPA Method 1603 followed by bacterial identification with Biolog MicroStation™ and ycjPCR assay, indicated that the prevalence of ycjM in the E. coli water isolates had a significant (p < 0.05, odds ratio ) spatial variation from 69.6% to 93.8%. These data suggest that E. coli profile using EPA Method 1603 or other ß-D-glucuronidase-activity-based methods may need further analysis using the ycjM profile to accurately determinate fecal pollution in water. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Leaner and meaner genomes in Escherichia coli

    DEFF Research Database (Denmark)

    Ussery, David


    A 'better' Escherichia coli K-12 genome has recently been engineered in which about 15% of the genome has been removed by planned deletions. Comparison with related bacterial genomes that have undergone a natural reduction in size suggests that there is plenty of scope for yet more deletions....

  16. Science Communication versus Science Education: The Graduate Student Scientist as a K-12 Classroom Resource (United States)

    Strauss, Jeff; Shope, Richard E., III; Terebey, Susan


    Science literacy is a major goal of science educational reform (NRC, 1996; AAAS, 1998; NCLB Act, 2001). Some believe that teaching science only requires pedagogical content knowledge (PCK). Others believe doing science requires knowledge of the methodologies of scientific inquiry (NRC, 1996). With these two mindsets, the challenge for science educators is to create models that bring the two together. The common ground between those who teach science and those who do science is science communication, an interactive process that galvanizes dialogue among scientists, teachers, and learners in a rich ambience of mutual respect and a common, inclusive language of discourse . The dialogue between science and non-science is reflected in the polarization that separates those who do science and those who teach science, especially as it plays out everyday in the science classroom. You may be thinking, why is this important? It is vital because, although not all science learners become scientists, all K-12 students are expected to acquire science literacy, especially with the implementation of the No Child Left Behind Act of 2001 (NCLB). Students are expected to acquire the ability to follow the discourse of science as well as connect the world of science to the context of their everyday life if they plan on moving to the next grade level, and in some states, to graduate from high school. This paper posits that science communication is highly effective in providing the missing link for K-12 students cognition in science and their attainment of science literacy. This paper will focus on the "Science For Our Schools" (SFOS) model implemented at California State Univetsity, Los Angeles (CSULA) as a project of the National Science Foundation s GK-12 program, (NSF 2001) which has been a huge success in bridging the gap between those who "know" science and those who "teach" science. The SFOS model makes clear the distinctions that identify science, science communication, science

  17. The Windows to the Universe Project: Using the Internet to Support K-12 Science Education (United States)

    Gardiner, L.; Johnson, R.; Bergman, J.; Russell, R.; Genyuk, J.; La Grave, M.


    The World Wide Web can be a powerful tool for reaching the public as well as students and teachers around the world, supporting both formal and informal science education. The Windows to the Universe Project, initiated in 1995, provides a case study of approaches for the use of the web to support earth and space science education and literacy efforts. Through the use of innovative approaches such as easy to use design, multi-level content, and science concepts presented in a broader background context that includes connections to culture and the humanities, Windows to the Universe is an accessible format for individuals of various ages and learning styles. A large global audience regularly uses the web site to learn about earth and space science as well as related humanities content such as myths from around the world. User surveys show that the site has over 4 millions users per year, 65 percent of which are K-12 teachers and students. Approximately 46 percent of users access the site once per week or more. Recently, we have had the opportunity to expand our efforts while we continue to update existing content based on new scientific findings and events. Earth science content on Windows to the Universe is currently growing with a new geology section and development efforts are underway to expand our space weather content with a new curriculum. Educational games allow users to learn about space in a playful context, and an online journaling tool further integrates literacy into the learning experience. In addition, we are currently translating the entire Windows to the Universe web site into Spanish. We have included educators in the project as co-designers from its inception, and by aggressively utilizing and providing professional development opportunities for teachers, the web site is now used in thousands of classrooms around the world. In the past year we have continued to support K-12 educators by adding to our suite of classroom activities and leading

  18. Identification of peptide-cross-linked trisdisaccharide peptide trimers in murein of Escherichia coli.


    Gmeiner, J


    Purified murein from Escherichia coli K-12 was degraded into disaccharide peptide fragments by endo-N-acetylmuramidase from Chalaropsis. About 5% of the total murein fragments were recovered as peptide-cross-linked trisdisaccharide peptide trimers.

  19. Are K-12 school environments harming students with obesity? A qualitative study of classroom teachers. (United States)

    Kenney, Erica L; Redman, Morgan T; Criss, Shaniece; Sonneville, Kendrin R; Austin, S Bryn


    Weight bias can negatively impact health, and schools may be risky environments for students with obesity. We aimed to explore teachers' perceptions of the school experiences and academic challenges of students with obesity. We conducted interviews with 22 teachers in the Northeast, mid-Atlantic, and Midwest in July-August 2014. All interviews were transcribed verbatim, coded, and analyzed for important themes by two researchers using the immersion/crystallization approach. Most teachers felt that students with obesity were more likely to have academic difficulties. Two main perceptions of the reasons for these difficulties emerged: (1) obesity led to lower self-esteem that caused students to participate less, and (2) poorer nutrition, increased screen time, and reduced physical activity were simultaneously causing obesity and poorer academic performance. A few teachers described colleagues who felt students with obesity were not as motivated to work hard in school as their peers. Many teachers described school health promotion efforts focused on weight reduction that could exacerbate weight stigma and risk of disordered eating. Students with obesity, particularly girls, may be at risk for negative social and academic experiences in K-12 schools and may be perceived as struggling academically by their teachers.

  20. NASA Education Activity Training (NEAT): Professional Development for Montana K-12 Teachers (United States)

    Williamson, Kathryn; McKenzie, D.; Des Jardins, A.; Key, J.; Kanode, C.; Willoughby, S.


    Piloted during the 2011-2012 academic year, the NASA Education Activity Training (NEAT) teacher workshop program has introduced five solar astronomy and space weather activities to over forty Montana K-12 teachers. Because many Montana schools are geographically isolated (40% of Montana students live more than 50 miles from a city) and/or serve traditionally underrepresented groups (primarily Native Americans), professional development for teachers can be costly and time consuming. However, with funding shared by the Atmospheric Imaging Assembly EPO team and the Montana Space Grant Consortium, graduate student specialists are able to host the two-hour NEAT workshops on-site at the schools free of charge, and participating teachers earn two continuing education credits. Leveraging the existing catalogue of research-based NASA activities, the featured NEAT activities were chosen for their ease-of-use and applicability to Montana science standards. These include three advanced activities for older students, such as a paper plate activity for the June 5th, 2012 Transit of Venus, Kinesthetic Astronomy, and the Herschel Infrared experiment, along with two simpler activities for the younger students, such as Solar Cookies and the Electromagnetic War card game. Feedback surveys show that NEAT workshop participants were interested and engaged in the activities and planned on using the activities in their classrooms. With such positive responses, the NEAT program has been a huge success and can serve as a model for other institutions looking to increase their space public outreach and education.

  1. Nutrition Education and Body Mass Index in Grades K-12: A Systematic Review. (United States)

    Price, Cayla; Cohen, Deborah; Pribis, Peter; Cerami, Jean


    Overweight and obese body mass index (BMI) status affects an increasing number of children in the United States. The school setting has been identified as a focus area to implement obesity prevention programs. A database search of PubMed, Education Search Complete, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) was conducted for peer-reviewed articles published between January 2005 and December 2015 pertaining to programs offered in the school setting to grades K-12 in the United States with a nutrition education component and measured BMI percentile or BMI z-score as an outcome. Seven studies focused on elementary (K-5) populations and 2 studies focused on grades 6-8. Among the 9 identified studies, those with long-term (greater than 1 year) implementation showed more pronounced results with positive impact on reducing overweight/obese BMI measures. This set of studies suggests that long-term nutrition education delivered in the school setting can provide children with tools to attain a healthy weight status. Additional studies examining participants' BMI status years after the initial study, and studies examining programs in grades 9-12 are needed to determine the most effective delivery time and methods. © 2017, American School Health Association.

  2. Energy, Society, and Education, with Emphasis on Educational Technology Policy for K-12 (United States)

    Chedid, Loutfallah Georges


    This paper begins by examining the profound impact of energy usage on our lives, and on every major sector of the economy. Then, the anticipated US energy needs by the year 2025 are presented based on the Department of Energy's projections. The paper considers the much-touted National Energy Policy Report, and identifies a major flaw where the policy report neglects education as a contributor to solving future energy problems. The inextricable interaction between energy solutions and education is described, with emphasis on education policy as a potential vehicle for developing economically and commercially sustainable energy systems that have a minimal impact on the environment. With that said, an earnest argument is made as to the need to educate science, technology, engineering, and mathematics (STEM) proficient individuals for the energy technology development workforce, starting with the K-12 level. A framework for the aforementioned STEM education policies is presented that includes a sustained national awareness campaign, address the teacher's salary issues, and addresses teacher quality issues. Moreover, the framework suggests a John Dewey-style "learning-by-doing" shift in pedagogy. Finally, the framework presents specific changes to the current national standards that would be valuable to the 21st century student.

  3. On the Role of an Authentic Research Experience for K-12 Science Teachers (United States)

    Zwicker, Andrew; Morgan, James; Delooper, John


    A variety of programs exist that offer K-12 teachers an opportunity to perform scientific research during the summer. Since 2001, the NSF has offered a Research Experience for Teachers, based upon the more common Research Experience for Undergraduates (REU). The DOE has had the Teacher Research Associate (TRAC) program since 1989 and currently sponsors the Academies Creating Teacher-Scientists (ACTS). In each of these, teachers spend 2-8 weeks performing research and developing classroom activities based upon this experience. Many programs assess changes in knowledge or attitude towards science, a few look at teacher retention, and one looked at student achievement after a teacher completed a program. Currently, PPPL runs two research programs for teachers, one running for two weeks, one for six weeks. One program recruits teachers nationally, while the other concentrates its efforts on a single school district. Each program will initially run for three years and we will report on our initial data that looks at attitudes, teaching philosophy, and content knowledge before beginning the research project. We will also report on expected outcomes after completion of the program.

  4. Students On-Line Atmospheric Research, SAGE III Outreach for K12 (United States)

    Woods, D. C.; Walters, S. C.; Moore, S. W.


    NASA's Stratospheric Aerosol and Gas Experiment III (SAGE III) is scheduled for launch on a Russian METEOR 3M spacecraft in 2001. SAGE III will monitor aerosols, clouds and several trace gases in the stratosphere, and extend the long-term data records obtained by its predecessors, SAGE I and SAGE II. The SAGE III project is very strongly committed to supporting educational outreach. The Students On-Line Atmospheric Research (SOLAR) program targets K-12 students and teachers nationwide, and offers a variety of science and technology activities related to the SAGE III experiment. These activities are designed to give students hands-on experience in collecting, analyzing, and reporting data. SOLAR focuses on helping students become familiar with the important roles that clouds, aerosols, and various trace gases play in the Earth Climate system. The program offers teacher workshops to provide training on guiding students in data collection activities, and to assist teachers with developing related curriculum materials. A one-week teacher workshop will be offered at the NASA Langley Research Center in June 2001. Currently, more than 120 teachers representing 25 US states are registered for the SOLAR program. This poster will highlight SOLAR activities for students and teachers.

  5. High-Performance Schools: Affordable Green Design for K-12 Schools; Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Plympton, P.; Brown, J.; Stevens, K.


    Schools in the United States spend $7.8 billion on energy each year-more than the cost of computers and textbooks combined, according to a 2003 report from the National Center for Education Statistics. The U.S. Department of Energy (DOE) estimates that these high utility bills could be reduced as much as 25% if schools adopt readily available high performance design principles and technologies. Accordingly, hundreds of K-12 schools across the country have made a commitment to improve the learning and teaching environment of schools while saving money and energy and protecting the environment. DOE and its public- and private-sector partners have developed Energy Design Guidelines for High Performance Schools, customized for nine climate zones in U.S. states and territories. These design guidelines provide information for school decision makers and design professionals on the advantages of energy efficiency and renewable energy designs and technologies. With such features as natural day lighting, efficient electric lights, water conservation, and renewable energy, schools in all types of climates are proving that school buildings, and the students and teachers who occupy them, are indeed high performers. This paper describes high performance schools from each of the nine climate zones associated with the Energy Design Guidelines. The nine case studies focus on the high performance design strategies implemented in each school, as well as the cost savings and benefits realized by students, faculty, the community, and the environment.

  6. STEM professional volunteers in K-12 competition programs: Educator practices and impact on pedagogy (United States)

    Zintgraff, Alfred Clifton

    This mixed methods dissertation study explored how secondary school educators in specific K-12 competition programs recruited and deployed STEM professional volunteers. The study explored which practices were viewed as most important, and how practices related to constructivist pedagogy, all from the viewpoint of educators. The non-positivist approach sought new knowledge without pursuing generalized results. Review of the literature uncovered extensive anecdotal information about current practices, and suggested that large investments are made in engaging volunteers. One National Science Foundation-sponsored study was identified, and its recommendations for a sustained research agenda were advanced. Three study phases were performed, one to explore practices and operationalize definitions, a second to rate practice's importance and their relation to pedagogy, and a third to seek explanations. Educators preferred recruiting local, meaning recruiting parents and former students, versus from industry or other employers. Most educators preferred volunteers with mentoring skills, and placing them in direct contact with students, versus deploying volunteers to help with behind-the-scenes tasks supporting the educator. Relationships were identified between the highest-rated practices and constructivism in programs. In STEM professional volunteers, educators see affordances, in the same way a classroom tool opens affordances. A model is proposed which shows educators considering practicality, pedagogy, knowledge and skills, and rapport when accessing the affordances opened by STEM professional volunteers. Benefits are maximized when programs align with strong industry clusters in the community.

  7. E. Coli (United States)

    ... Linked to Leafy Greens Learn about E. coli infections and how they can be prevented Escherichia coli (abbreviated as E. coli ) are bacteria found in the environment, foods, and intestines of people and animals. E. coli are a ...

  8. E. Coli (United States)

    ... For Kids > E. Coli Print A A A en español E. coli What Is E. Coli ? E. coli is a common type of bacteria that can get into food, like beef and vegetables. E. coli is short for the bacteria's medical name Escherichia coli . The strange thing about these bacteria — and lots ...

  9. Connecting Three Pivotal Concepts in K-12 Science State Standards and Maps of Conceptual Growth to Research in Physics Education

    CERN Document Server

    Singh, Chandralekha


    This paper describes three conceptual areas in physics that are particularly important targets for educational interventions in K-12 science. These conceptual areas are force and motion, conservation of energy, and geometrical optics, which were prominent in the US national and four US state standards that we examined. The four US state standards that were analyzed to explore the extent to which the K-12 science standards differ in different states were selected to include states in different geographic regions and of different sizes. The three conceptual areas that were common to all the four state standards are conceptual building blocks for other science concepts covered in the K-12 curriculum. Since these three areas have been found to be ripe with deep student misconceptions that are resilient to conventional physics instruction, the nature of difficulties in these areas is described in some depth, along with pointers towards approaches that have met with some success in each conceptual area.

  10. Businesses assisting K--12 science instruction: Four case studies of long-term school partnerships (United States)

    van Trieste, Lynne M.

    Businesses lack enough qualified applicants to fill the increasing need for scientists and engineers while educators lack many resources for science programs in K-12 schools. This series of case studies searched for successful collaborations between the two in four geographic locations: Boise, Idaho; Dallas, Texas; Los Angeles County, California, and Orange County, California. These science education partnerships were investigated to gain an understanding of long-term partnership structure, functioning and evaluation methods. Forty-nine individual interviews with representatives from the groups of stakeholders these programs impact were also conducted. Stakeholder groups included students, teachers, parents, school administrators, business liaisons, and non-profit representatives. Several recurring themes in these partnerships reinforced the existing literature research findings. Collaboration and communication between partners, teacher professional development, the need for more minority and female representation in physical science careers, and self-efficacy in relation to how people come to view their scientific abilities, are among these themes. Topics such as program replication, the importance of role models, programs using "hands-on" activities, reward systems for program participants, and program outcome measurement also emerged from the cases investigated. Third-party assistance by a non-profit entity is occurring within all of these partnerships. This assistance ranges from a service providing material resources such as equipment, lesson plans and meeting space, to managing the partnership fundraising, program development and evaluations. Discussions based upon the findings that support or threaten sustainment of these four partnerships, what a "perfect" partnership might look like, and areas in need of further investigation conclude this study.

  11. C-MORE Science Kits: Putting Technology in the Hands of K-12 Teachers and Students (United States)

    Achilles, K.; Weersing, K.; Daniels, C.; Puniwai, N.; Matsuzaki, J.; Bruno, B. C.


    The Center for Microbial Oceanography: Research and Education (C-MORE) is a NSF Science and Technology Center based at the University of Hawaii. The C-MORE education and outreach program offers a variety of resources and professional development opportunities for science educators, including online resources, participation in oceanography research cruises, teacher-training workshops, mini-grants to incorporate microbial oceanography-related content and activities into their classroom and, most recently, C- MORE science kits. C-MORE science kits provide hands-on classroom, field, and laboratory activities related to microbial oceanography for K-12 students. Each kit comes with complete materials and instructions, and is available free of charge to Hawaii's public school teachers. Several kits are available nationwide. C-MORE science kits cover a range of topics and technologies and are targeted at various grade levels. Here is a sampling of some available kits: 1) Marine Murder Mystery: The Case of the Missing Zooxanthellae. Students learn about the effect of climate change and other environmental threats on coral reef destruction through a murder-mystery experience. Participants also learn how to use DNA to identify a suspect. Grades levels: 3-8. 2) Statistical sampling. Students learn basic statistics through an exercise in random sampling, with applications to microbial oceanography. The laptops provided with this kit enable students to enter, analyze, and graph their data using EXCEL. Grades levels: 6-12. 3) Chlorophyll Lab. A research-quality fluorometer is used to measure the chlorophyll content in marine and freshwater systems. This enables students to compare biomass concentrations in samples collected from various locations. Grades levels: 9-12. 4) Conductivity-Temperature-Depth (CTD). Students predict how certain variables (e.g., temperature, pressure, chlorophyll, oxygen) vary with depth. A CTD, attached to a laptop computer, is deployed into deep water

  12. Innovative CEA Information Server: Helping K--12 Teachers and Students Navigate the EUVE Mission Archive (United States)

    Kronberg, F.; Hawkins, I.; Levandovsky, N.; Wong, L.; Arellano, V.; Ford, P.; Nguyen, K.; Malina, R. F.


    Internet access to the Extreme Ultraviolet Explorer (EUVE) mission archive for participants in the Science Online and Science Information Infrastructure programs will be facilitated by an innovative, World Wide Web--based data server being developed at the UC Berkeley Center for EUV Astrophysics (CEA). The Innovative CEA Information Server, being developed for the Science Education Program, will allow the user to easily select and access material from the EUVE mission archive. The entire archive, as part of an overarching CEA project, the EUVE Knowledge Base, will be logically structured into knowledge units. Each knowledge unit is defined as ``all of the information available at CEA about a given subject encapsulated into a self-contained, single, multimedia object.'' The user will be able to specify parameters that indicate the desired levels of complexity, breadth or scope, and format (e.g., text or graphics) of the requested knowledge units. The K--12 education materials for this Server are being developed at CEA via a ``Partners in Science'' teacher internship program funded by Research Corporation. Dr. Nelli Levandovsky, a physics teacher from San Francisco Unified School District's Galileo high school, created the following two tutorial plans this past summer: ``Be an Engineer---Learn How to Operate a Satellite'' and ``Be a Scientist---Learn How to Become a Space Researcher.'' Current development efforts are concentrated in two areas: (1) reviewing types of EUVE archival data and mission information and how these knowledge units can be packaged and presented; and (2) investigating how issues of breadth (e.g., scope or extent) and depth (e.g., complexity) of the knowledge units can be better presented in the construction of the Server. This work is supported by NASA contract NAS5-29298.

  13. Final report on key comparison CCEM-K12: AC-DC current transfer standards (United States)

    Budovsky, Ilya


    The circulation of the travelling standards in the CIPM key comparison CCEM-K12 of AC-DC current transfer difference began in March 2005 and was completed in April 2007. The travelling standards were lost on their way from the last participant to the pilot laboratory. Since, prior to their disappearance, the travelling standards exhibited exceptional stability, the CCEM Working Group on Low-Frequency Quantities decided in June 2008 to accept the results of the comparison as valid without the final measurement by the pilot laboratory. The AC-DC transfer differences of the travelling standards have been measured at 10 mA and 5 A, and at the frequencies 10 Hz, 55 Hz, 1 kHz, 10 kHz, 20 kHz, 50 kHz and 100 kHz. The key comparison reference values were calculated as the weighted means of the results of the National Metrology Institutes (NMIs) with independent realizations of primary standards and low reported uncertainties. The degrees of equivalence relative to the key comparison reference values, as well as between pairs of NMIs, have been determined for the measurement points and show very good agreement. All but three of the calculated degrees of equivalence relative to the key comparison reference values are within the limits of the expanded uncertainties. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  14. Strategies for Integrating Content from the USGCRP Climate and Health Assessment into the K-12 Classroom (United States)

    Haine, D. B.


    That the physical environment shapes the lives and behaviors of people is certainly not news, but communicating the impact of a changing climate on human health and predicting the trajectory of these changes is an active area of study in public health. From air quality concerns to extreme heat to shifts in the range of disease vectors, there are many opportunities to make connections between Earth's changing climate and human health. While many science teachers understand that addressing human health impacts as a result of a changing climate can provide needed relevance, it can be challenging for teachers to do so given an already packed curriculum. This session will share instructional strategies for integrating content from the USGCRP Climate and Health Assessment (CHA) by enhancing, rather than displacing content related to climate science. This presentation will feature a data interpretation activity developed in collaboration with geoscientists at the University of North Carolina's Gillings School of Public Health to convey the connection between air quality, climate change and human health. This classroom activity invites students to read excerpts from the CHA and interpret data presented in the scientific literature, thus promoting scientific literacy. In summarizing this activity, I will highlight strategies for effectively engaging geoscientists in developing scientifically rigorous, STEM-focused educational activities that are aligned to state and national science standards and also address the realities of the science classroom. Collaborating with geoscientists and translating their research into classroom activities is an approach that becomes more pertinent with the advent of the Next Generation Science Standards (NGSS). Thus, the USGCRP Climate and Health Assessment represents an opportunity to cultivate science literacy among K-12 students while providing relevant learning experiences that promote integration of science and engineering practices as

  15. Team Mentoring for Interdisciplinary Team Science: Lessons From K12 Scholars and Directors. (United States)

    Guise, Jeanne-Marie; Geller, Stacie; Regensteiner, Judith G; Raymond, Nancy; Nagel, Joan


    Mentoring is critical for academic success. As science transitions to a team science model, team mentoring may have advantages. The goal of this study was to understand the process, benefits, and challenges of team mentoring relating to career development and research. A national survey was conducted of Building Interdisciplinary Research Careers in Women's Health (BIRCWH) program directors-current and former scholars from 27 active National Institutes of Health (NIH)-funded BIRCWH NIH K12 programs-to characterize and understand the value and challenges of the team approach to mentoring. Quantitative data were analyzed descriptively, and qualitative data were analyzed thematically. Responses were received from 25/27 (93%) program directors, 78/108 (72%) current scholars, and 91/162 (56%) former scholars. Scholars reported that team mentoring was beneficial to their career development (152/169; 90%) and research (148/169; 88%). Reported advantages included a diversity of opinions, expanded networking, development of stronger study designs, and modeling of different career paths. Challenges included scheduling and managing conflicting opinions. Advice by directors offered to junior faculty entering team mentoring included the following: not to be intimidated by senior mentors, be willing to navigate conflicting advice, be proactive about scheduling and guiding discussions, have an open mind to different approaches, be explicit about expectations and mentors' roles (including importance of having a primary mentor to help navigate discussions), and meet in person as a team. These findings suggest that interdisciplinary/interprofessional team mentoring has many important advantages, but that skills are required to optimally utilize multiple perspectives.

  16. VISL: A Virtual Ice Sheet Laboratory For Outreach and K-12 Education (United States)

    Cheng, D. L. C.; Halkides, D. J.; Larour, E. Y.; Moore, J.; Dunn, S.; Perez, G.


    We present an update on our developing Virtual Ice Sheet Laboratory (VISL). Geared to K-12 classrooms and the general public, VISL's main goal is to improve climate literacy, especially in regards to the crucial role of the polar ice sheets in Earth's climate and sea level. VISL will allow users to perform guided experiments using the Ice Sheet System Model (ISSM), a state-of-the-art ice flow model developed at NASA's Jet Propulsion Laboratory and UC Irvine that simulates the near-term evolution of the ice sheets on Greenland and Antarctica. VISL users will access ISSM via a graphical interface that can be launched from a web browser on a computer, tablet or smart phone. Users select climate conditions and run time by moving graphic sliders then watch how a given region evolves in time under those conditions. Lesson plans will include conceptual background, instructions for table top experiments related to the concepts addressed in a given lesson, and a guide for performing model experiments and interpreting their results. Activities with different degrees of complexity will aim for consistency with NGSS Physical Science criteria for different grade bands (K-2, 3-5, 6-8, and 9-12), although they will not be labeled as such to encourage a broad user base. Activities will emphasize the development of physical intuition and critical thinking skills, understanding conceptual and computational models, as well as observation recording, concept articulation, hypothesis formulation and testing, and mathematical analysis. At our present phase of development, we seek input from the greater science education and outreach communities regarding VISL's planned content, as well as additional features and topic areas that educators and students would find useful.

  17. Assessment Strategies for Implementing Ngss in K12 Earth System Science Classrooms (United States)

    McAuliffe, C.


    Several science education researchers have led assessment efforts that provide strategies particularly useful for evaluating the threedimensional learning that is central to NGSS (DeBarger, A. H., Penuel, W. R., Harris, C. J., Kennedy, C. K., 2016; Knight, A. M. & McNeill, K. L., 2015; McNeill, K. L., KatshSinger, R. & Pelletier, P., 2015; McNeill K.L.,, 2015; McNeill, K.L., & Krajcik, J.S., 2011; Penuel, W., 2016). One of the basic premises of these researchers is that, "Assessment is a practice of argument from evidence based on what students say, do, and write" and that "the classroom is the richest place to gather evidence of what students know (Penuel, W., 2016). The implementation of the NGSS in Earth System Science provides a unique opportunity for geoscience education researchers to study student learning and contribute to the development of this research as well as for geoscience educators to apply these approaches and strategies in their own work with K12 inservice and preservice educators. DeBarger, A. H., Penuel, W. R., Harris, C. J., Kennedy, C. K. (2016). Building an Assessment Argument to Design and Use Next Generation Science Assessments in Efficacy Studies of Curriculum Interventions. American†Journal†of†Evaluation†37(2) 174192Æ Knight, A. M. & McNeill, K. L. (2015). Comparing students' individual written and collaborative oral socioscientific arguments. International Journal of Environmental and Science Education.10(5), 23647. McNeill, K. L., KatshSinger, R. & Pelletier, P. (2015). Assessing science practices-Moving your class along a continuum. Science Scope. McNeill, K.L., & Krajcik, J.S. (2011). Supporting Grade 5-8 Students in Constructing Explanations in Science: The Claim, Evidence, and Reasoning Framework for Talk and Writing. Upper Saddle River, New Jersey: Pearson. Penuel, W. (2016). Classroom Assessment Strategies for NGSS Earth and Space Sciences. Implementing†the†NGSS†Webinar†Series, February 11, 2016.

  18. Pre-expression of a sulfhydryl oxidase significantly increases the yields of eukaryotic disulfide bond containing proteins expressed in the cytoplasm of E.coli

    Directory of Open Access Journals (Sweden)

    Enlund Eveliina


    Full Text Available Abstract Background Disulfide bonds are one of the most common post-translational modifications found in proteins. The production of proteins that contain native disulfide bonds is challenging, especially on a large scale. Either the protein needs to be targeted to the endoplasmic reticulum in eukaryotes or to the prokaryotic periplasm. These compartments that are specialised for disulfide bond formation have an active catalyst for their formation, along with catalysts for isomerization to the native state. We have recently shown that it is possible to produce large amounts of prokaryotic disulfide bond containing proteins in the cytoplasm of wild-type bacteria such as E. coli by the introduction of catalysts for both of these processes. Results Here we show that the introduction of Erv1p, a sulfhydryl oxidase and a disulfide isomerase allows the efficient formation of natively folded eukaryotic proteins with multiple disulfide bonds in the cytoplasm of E. coli. The production of disulfide bonded proteins was also aided by the use of an appropriate fusion protein to keep the folding intermediates soluble and by choice of media. By combining the pre-expression of a sulfhydryl oxidase and a disulfide isomerase with these other factors, high level expression of even complex disulfide bonded eukaryotic proteins is possible Conclusions Our results show that the production of eukaryotic proteins with multiple disulfide bonds in the cytoplasm of E. coli is possible. The required exogenous components can be put onto a single plasmid vector allowing facile transfer between different prokaryotic strains. These results open up new avenues for the use of E. coli as a microbial cell factory.

  19. Seismic Site Characterizations and Earthquake Loss Estimation Analyses for K-12 Schools in Washington State (United States)

    Cakir, R.; Walsh, T. J.; Hayashi, K.; Norman, D. K.; Lau, T.; Scott, S.


    prioritize mitigation actions. This project has provided unique hands-on geophysical survey opportunities for the K-12 and undergraduate students.

  20. Educating K-12 Students about Glacier Dynamics in a Changing Climate (United States)

    Stearns, L. A.; Hamilton, G. S.


    Public awareness of climate change is growing in the United States. Popular movies, books and magazines are frequently addressing the issue of global warming - some with careful scientific research, but many with unrealistic statements. Early education about the basic principles and processes of climate change is necessary for the general public to distinguish fact from fiction. The U.S. National Science Foundation's GK-12 program (GK-12; grades K to 12) currently in its sixth year, provides an opportunity for scientific enrichment for students and their teachers at the K-12 level through collaborative pairings with science and engineering graduate students (the Fellows). The NSF GK-12 program at the University of Maine has three goals: to enrich the scientific education of the students by providing role models, expertise, and equipment that may not be accessible otherwise; to provide professional development for the teachers through curriculum enrichment and participation at science conferences; and to improve the teaching and communication skills of the Fellows. The University of Maine is one of over 100 U. S. universities participating in this program. During the 2004-05 academic year, 11 graduate and one undergraduate student Fellows, advised by University faculty members, taught at schools across the state of Maine. Fellows from, biology, earth science, ecology, engineering, food science, forestry, and marine science, and taught in their area of expertise. We created a hands-on activity for middle and high school students that describes glacier mass balance in a changing climate. The students make a glacier using glue, water and detergent ('flubber') and construct a glacier valley using plastic sheeting. Flubber behaves in mechanically similar ways to glacier ice, undergoing plastic deformation at low stresses and exhibiting brittle failure at high stresses. Students are encouraged to run several tests with different values for valley slope, glacier mass

  1. One Model for Scientist Involvement in K-12 Education: Teachers Experiencing Antarctica and the Arctic Program (United States)

    Meese, D.; Shipp, S. S.; Porter, M.; Bruccoli, A.


    Scientists involved in the NSF-funded Teachers Experiencing Antarctica and the Arctic (TEA) Program integrate a K-12 science teacher into their polar field project. Objectives of the program include: having the science teacher immersed in the experience of research; 2) through the teacher, leveraging the research experience to better inform teaching practices; and 3) sharing the experience with the broader educational and general community. The scientist - or qualified team member - stays involved with the teacher throughout the program as a mentor. Preparation of the teacher involves a week-long orientation presented by the TEA Program, and a two week pre-expedition visit at the scientist's institution. Orientation acquaints teachers with program expectations, logistical information, and an overview of polar science. While at the scientist's institution, the teacher meets the team, prepares for the field, and strengthens content knowledge. In the field, the teacher is a team member and educational liaison, responding to questions from students and colleagues by e-mail, and posting electronic journals describing the research experience. Upon return, the teachers work closely with colleagues to bring the experience of research into classrooms through creation of activities, design of longer-term student investigations, and presentations at scientific, educational, and community meetings. Interaction with the scientific team continues with a visit by the scientist to the teacher's classrooms, collaboration on presentations at scientific meetings, and consultation on classroom activities. In some cases, the teacher may participate in future expeditions. The involvement by scientists in mentor relationships, such as those of the TEA Program, is critical to improving science education. Many teachers of science have not had the opportunity to participate in field research, which offers valuable first-hand experience about the nature of science, as well as about specific

  2. The major aminoglycoside-modifying enzyme AAC(3)-II found in Escherichia coli determines a significant disparity in its resistance to gentamicin and amikacin in China. (United States)

    Xiao, Yonghong; Hu, Yunjian


    The aim of this study was to investigate the prevalence of aminoglycoside-modifying enzymes in Escherichia coli in different areas of China and to explore the relationship between pandemic enzyme type and bacterial resistance to antimicrobial agents in China. Gentamicin- or etimicin-resistant clinical isolates of E. coli were collected from different areas of China, and the in vitro antibacterial activity of 11 aminoglycoside agents was determined using standard (Clinical and Laboratory Standards Institute) agar dilution methods. Twelve aminoglycoside-modifying enzyme genes were detected by PCR and confirmed by DNA sequencing. A total of 205 E. coli strains were collected from nine hospitals in seven cities. All strains were highly resistant to gentamicin or etimicin, whereas resistance to tobramycin, netilmicin, and kanamycin was slightly lower. However, less than 15% of isolates were resistant to amikacin and isepamicin. Of the gentamicin-resistant strains, 88.2% and 86.7% were sensitive to isepamicin and amikacin, respectively. Five aminoglycoside-modifying enzyme genes were detected in 191 strains, whereas the remaining 14 strains were negative. The most common gene type was aac(3)-II (162 strains), followed by aac(6')-I (50 strains), ant(3″)-I (28 strains), aph(3')-II (20 strains), and ant(2″)-I (20 strains). Ninety-five strains yielded aac(3)-II only, whereas the others contained two or three genes. The three main gene combinations were aac(6')-I/aac(3)-II (28 strains), aac(3)-II/ant(3″)-I (11 strains), and aac(3)-II/aac(6')-I (10 strains). Regional bacterial resistance and enzyme distribution were roughly similar, although minor differences were found in Guangzhou, Jinan, and Dalian, which were the sources of most of the amikacin- or isepamicin-resistant strains. Chinese clinical isolates of E. coli remain highly resistant to gentamicin and etimicin, but are susceptible to amikacin and isepamicin. The dominant type of aminoglycoside-modifying enzyme

  3. Implementing Network Video for Traditional Security and Innovative Applications: Best Practices and Uses for Network Video in K-12 Schools (United States)

    Wren, Andrew


    Administrators are constantly seeking ways to cost-effectively and adequately increase security and improve efficiency in K-12 schools. While video is not a new tool to schools, the shift from analog to network technology has increased the accessibility and usability in a variety of applications. Properly installed and used, video is a powerful…

  4. A Review of Research on Content-Based Foreign/Second Language Education in US K-12 Contexts (United States)

    Tedick, Diane J.; Wesely, Pamela M.


    This review of the extant research literature focuses on research about content-based language instruction (CBI) programmes in K-12 foreign/second language education in the USA. The review emphasises studies on one-way language immersion (OWI) and two-way language immersion (TWI) programmes, which are school-based and subject matter-driven. OWI…

  5. Infusing Multicultural Education into the Curriculum: Preparing Pre-Service Teachers to Address Homophobia in K-12 Schools (United States)

    Jones, Joseph R.


    This article discusses the role multicultural education can play in addressing homophobia in K-12 schools. The author explores the lack of multiculturalism courses in undergraduate teacher education programs. To address the lack of multiculturalism courses, three instructional activities are offered that faculty in teacher education programs can…

  6. Integrating Online GIS into the K-12 Curricula: Lessons from the Development of a Collaborative GIS in Michigan (United States)

    Henry, Paul; Semple, Hugh


    GIS has shown promise in Project Based Learning (PBL) environments, but many obstacles exist in its integration into school curriculums. This article discusses the development and utilization of an online GIS tool that was created to illustrate that the perceptual gap between relevance and ease of use of GIS software can be bridged at the K-12

  7. Universal Design for Learning in K-12 Educational Settings: A Review of Group Comparison and Single-Subject Intervention Studies (United States)

    Crevecoeur, Yvel C.; Sorenson, Sarah E.; Mayorga, Victor; Gonzalez, Adriana P.


    This literature review on Universal Design for Learning (UDL) included articles from January 1984 through June 2014. We (a) investigated the UDL educational framework without the inclusion of other major K-12 educational frameworks in learning environments, (b) reported researchers' scope and depth of use of the UDL principles, and (c) focused our…

  8. Utilizing a School-University Collaborative Partnership to Design, Present, and Support Pre-K-12 Coursework on Differentiated Instruction (United States)

    Neville, Elizabeth


    Differentiated instruction should be evident in every classroom; however, it is particularly critical in Professional Development Schools (PDS) that have the dual focus of instruction for both Pre-K-12 students and university students completing their final internship experience. In this article, the author illustrates a university and school…

  9. The Effectiveness of Educational Technology Applications for Enhancing Mathematics Achievement in K-12 Classrooms: A Meta-Analysis (United States)

    Cheung, Alan C. K.; Slavin, Robert E.


    The present review examines research on the effects of educational technology applications on mathematics achievement in K-12 classrooms. Unlike previous reviews, this review applies consistent inclusion standards to focus on studies that met high methodological standards. In addition, methodological and substantive features of the studies are…

  10. A Review of Research Methodologies Used in Studies on Mobile Handheld Devices in K-12 and Higher Education Settings (United States)

    Cheung, Wing Sum; Hew, Khe Foon


    Mobile handheld devices are increasingly being used in education. In this paper, we undertook a review of empirical based articles to summarise the current research regarding the use of mobile handheld devices (personal digital assistants/PDAs, palmtops, and mobile phones) in K-12 and higher education settings. This review was guided by the…

  11. Emotional Intelligence in the K-12 Curriculum and its Relationship to American Workplace Needs: A Literature Review (United States)

    Opengart, Rose


    The purpose of this paper was to review the content of existing social-emotional learning (SEL) programs in the American K-12 curriculum and the relationship between the programs and the needs of the American workplace. SEL programs were examined for their content and compared to the research indicating critical EI skills for the workplace.…

  12. The Impact a Technology Leader and Their Leadership Style Makes in K-12 Classroom Teacher's Implementation of Technology (United States)

    Smith, Molly S.


    The purpose of the study was to examine how public school technology leaders' leadership styles in Pennsylvania schools impact K-12 classroom teachers' integration of technology. The study collected data using two online surveys, the MLQ and LoTi, which measured leadership styles and levels of technology integration. Despite the large sample size…

  13. Incremental Progress: Re-Examining Field Experiences in K-12 Online Learning Contexts in the United States (United States)

    Archambault, Leanna; Kennedy, Kathryn; Shelton, Catharyn; Dalal, Medha; McAllister, Laura; Huyett, Sabrina


    Despite the call for a transformation of teacher education in the 21st century, surprisingly little has changed. This includes how the practical, hands-on component, known as a field experience is structured. Previous research, conducted in 2010, specifically examining how teacher education programs address K-12 online learning through their field…

  14. The Elephant in the (Class)Room: Parental Perceptions of LGBTQ-Inclusivity in K-12 Educational Contexts (United States)

    Ullman, Jacqueline; Ferfolja, Tania


    While little is known about parental beliefs and desires regarding LGBTQ-inclusive education, assumptions about these appear to justify teachers', curriculum writers' and policy makers' silences regarding sexuality and gender diversity in the K-12 classroom. Thus, in order to better inform educators' practices, this paper presents an analysis of…

  15. Exploring Relationships between K-12 Music Educators' Demographics, Perceptions of Intrapreneuring, and Motivation at Work (United States)

    Hanson, Josef


    Gifford Pinchot III coined the term "intrapreneur" to recognize "dreamers who do": individuals who transform ideas into new endeavors within existing organizations. The purpose of this study was to gauge the salience of intrapreneuring for K-12 music teachers and examine how its attributes and behaviors relate to teachers'…

  16. A Conceptual Framework for Digital Libraries for K-12 Mathematics Education: Part 1, Information Organization, Information Literacy, and Integrated Learning (United States)

    Chen, Hsin-liang; Doty, Philip


    This article is the first of two that present a six-part conceptual framework for the design and evaluation of digital libraries meant to support mathematics education in K-12 settings (see also pt. 2). This first article concentrates on (1) information organization, (2) information literacy, and (3) integrated learning with multimedia materials.…

  17. A Conceptual Framework for Digital Libraries for K-12 Mathematics Education: Part 2, New Educational Standards, Policy Making, and Accountability (United States)

    Chen, Hsin-liang; Doty, Philip


    This paper is the second of two (see pt. 1) that describe a six-part conceptual framework for designing and evaluating digital libraries for mathematics education in K-12 settings: information literacy, information organization, integrated learning, adoption of new educational standards, integration of pertinent changes in educational policy…

  18. The Second Digital Divide and Its Effect on African-American (K-12) School-Age Children (United States)

    Barrett, Christopher A.


    The qualitative phenomenological study explored the perceptions of educators and parents of African-American (K-12) school-age children on how the children were using technology. The study was conducted in the Memphis City Public School System (MCS) and was limited to three schools in a school district. Common themes emerged from the analysis of…

  19. How Do Sustainable Schools Integrate Sustainability Education? An Assessment of Certified Sustainable K-12 Schools in the United States (United States)

    Warner, Benjamin P.; Elser, Monica


    We provide an overview of research in sustainability education. We argue that the interconnectedness of environmental sustainability programs at K-12 schools is one metric by which sustainability education can be conceptualized. We present a new measure of whole-school sustainability, or "interconnectedness," and then use it to compare…

  20. The Influence of Noncognitive Domains on Academic Achievement in K-12. Research Report. ETS RR-09-34 (United States)

    Lee, Jihyun; Shute, Valerie J.


    This paper identifies three noncognitive domains relevant for academic achievement in K-12-- student engagement, behavioral learning strategies, and school climate. The paper also documents empirical findings that show relationships between these three noncognitive domains and academic achievement, especially in the areas of reading and…

  1. Toward a More Nuanced Approach to Program Effectiveness Assessment: Hierarchical Linear Models in K-12 Program Evaluation (United States)

    Newton, Xiaoxia A.; Llosa, Lorena


    Most K-12 evaluations are designed to make inferences about how a program implemented at the classroom or school level affects student learning outcomes and such inferences inherently involve hierarchical data structure. One methodological challenge for evaluators is linking program implementation factors typically measured at the classroom or…

  2. The Perceived Work Ethic of K-12 Teachers by Generational Status: Generation X vs. Baby Boom Generation (United States)

    Petty, Gregory C.


    This was an investigation of the work ethic of K-12 educators from Generation X and Baby Boomer generations. Teachers of the baby boom generation were born between 1946 and 1964, and many are beginning to retire. There is an impending teacher shortage due to the large numbers of this group retiring or leaving the profession. School administrators…

  3. #TwitterforTeachers: The Implications of Twitter as a Self-Directed Professional Development Tool for K-12 Teachers (United States)

    Visser, Ryan D.; Evering, Lea Calvert; Barrett, David E.


    This mixed-methods study explores how K-12 teachers use Twitter. An online survey was disseminated via Twitter to gauge their usage of, access to, and perceptions of Twitter. The results indicated that teachers highly value Twitter as a means of self-directed professional development. Respondents who reported using Twitter multiple times a day…

  4. Getting to the Fourth Year: The Instruments and Protocols Used To Study the Practice of Beginning K-12 Science Teachers. (United States)

    Davis, George; Simpson, Patricia R.; Johnson, Bruce; Wallace, Alison

    Getting to the Fourth Year is a study being conducted by the Teacher Research Network (TRN) in Minnesota. The TRN was established in 1998 by five higher education institutions that collectively prepare about 75% of all K-12 teachers in the state. The vision of the collaborative was to begin the process of transforming teacher education in…

  5. The Effects of Teacher Background, Teacher Preparation, and Support on Attitudes and Expectations of K-12 Urban Music Educators (United States)

    Doyle, Jennifer L.


    The purpose of this study was to determine the effects of personal and professional background factors, teacher preparation, and support on urban music teacher disposition. Specifically, the study aimed to examine the status of K-12 urban music education; verify the psychometric appropriateness of the researcher-created survey instrument; analyze…

  6. Guide for the Development of Library Skills and Services in the Sulphur Springs Independent School District, Grades K-12. (United States)

    Sulphur Springs Independent School District, TX.

    This guide consists of a series of behavioral objectives for the student, K-12. It has been prepared by librarians to aid teachers in using the library as an extension of their classroom teaching and to aid librarians in providing the needed materials and activities for both teachers and students. It should be useful to teachers in planning…

  7. Preparing for the Flu (Including 2009 H1N1 Flu): A Communication Toolkit for Schools (Grades K-12) (United States)

    Centers for Disease Control and Prevention, 2010


    The purpose of "Preparing for the Flu: A Communication Toolkit for Schools" is to provide basic information and communication resources to help school administrators implement recommendations from CDC's (Centers for Disease Control and Prevention) Guidance for State and Local Public Health Officials and School Administrators for School (K-12)…

  8. From Silence to Safety and Beyond: Historical Trends in Addressing Lesbian, Gay, Bisexual, Transgender Issues in K-12 Schools (United States)

    Griffin, Pat; Ouellett, Mathew


    The purpose of this article is to provide an historical overview of changing perspectives in education practice and literature on addressing lesbian, gay, bisexual, transgender (LGBT) issues in public K-12 schools. This article describes how the presentation and analysis of lesbian, gay, bisexual, and transgender issues in the past 80 years have…

  9. The Dual Role of Instructor/Designer: Use of Instructional Design Practices in the Design of K-12 Online Instruction (United States)

    Hooie, Jennifer H.


    As K-12 online offerings gain in popularity, districts search for cost effective ways to implement online courses. Most districts opt to use current staff members to both develop and teach the online offerings. Merrill (The future of instructional design: The proper study of instructional design, 2007) explains that individuals with no formal…

  10. Evaluation of Online Teacher and Student Materials for the Framework for K-12 Science Education Science and Engineering Crosscutting Concepts (United States)

    Schwab, Patrick


    The National Research Council developed and published the "Framework for K-12 Science Education," a new set of concepts that many states were planning on adopting. Part of this new endeavor included a set of science and engineering crosscutting concepts to be incorporated into science materials and activities, a first in science…

  11. A Review of Computer Science Resources for Learning and Teaching with K-12 Computing Curricula: An Australian Case Study (United States)

    Falkner, Katrina; Vivian, Rebecca


    To support teachers to implement Computer Science curricula into classrooms from the very first year of school, teachers, schools and organisations seek quality curriculum resources to support implementation and teacher professional development. Until now, many Computer Science resources and outreach initiatives have targeted K-12 school-age…

  12. Prioritization of K-12 World Language Education in the United States: State Requirements for High School Graduation (United States)

    O'Rourke, Polly; Zhou, Qian; Rottman, Isaac


    In view of the importance of increasing multilingualism in the United States, the current study examined state policy for high school graduation requirements in the 50 states and the District of Columbia as an index of the way in which the study of world language is positioned and prioritized in K--12 education. Only seven states require the study…

  13. Guided by Principles: Shaping the State of California's Role in K-12 Public School Facility Funding. Policy Research Working Paper (United States)

    Center for Cities & Schools, 2015


    The Governor, members of the legislature and other key stakeholders have identified concerns about the State of California's approach to funding K-12 school facilities, but they have not yet formulated a consensus going forward on the state role and responsibilities for school district facilities. To inform the school facilities funding policy…

  14. Roadmap for K-12 and Postsecondary Linkages: Key Focus Areas to Ensure Quality Implementation. Data for Action (United States)

    Data Quality Campaign, 2014


    States rely on data from both the K-12 and postsecondary sectors to inform policy discussions; chart the progress of students, schools, districts, colleges, and the state; pinpoint best practices and areas of need; allocate scarce resources; and make other important education decisions every day. However, states need to securely link limited, but…

  15. Music Educator Vacancies in Faith-Based K-12 Schools in the United States: 2013-2014 (United States)

    Hash, Phillip M.


    The purpose of this study was to analyze and summarize characteristics of music educator vacancies in faith-based K-12 schools in the United States for the 2013-2014 academic year. Data extracted from placement notices and supplemental sources included demographic information, job responsibilities, and employment requirements for 153 listings in…

  16. Use of Web 2.0 Technologies in K-12 and Higher Education: The Search for Evidence-Based Practice (United States)

    Hew, Khe Foon; Cheung, Wing Sum


    Evidence-based practice in education entails making pedagogical decisions that are informed by relevant empirical research evidence. The main purpose of this paper is to discuss evidence-based pedagogical approaches related to the use of Web 2.0 technologies in both K-12 and higher education settings. The use of such evidence-based practice would…

  17. Feedback from the Field: What Novice PreK-12 ESL Teachers Want to Tell TESOL Teacher Educators (United States)

    Baecher, Laura


    Programs in the United States that certify PreK-12 teachers in English as a second language (ESL) must meet high and consistent standards in their preservice preparation. However, there is little empirical evidence on the degree to which such preparation actually meets the needs of teachers once they begin their careers. Teaching English to…

  18. Identifying a Statistical Model for North Dakota K-12 Public School Transportation Funding by Comparing Fifteen State Transportation Funding Formulas (United States)

    Holen, Steven M.


    The purpose of this study was to review the history of North Dakota K-12 transportation funding system, identify how school districts are reimbursed for transportation expenses, and compare this information with fourteen other state transportation funding systems. North Dakota utilizes a block grant structure that has been in place since 1972 and…

  19. Measurement Invariance of Second-Order Factor Model of the Multifactor Leadership Questionnaire (MLQ) across K-12 Principal Gender (United States)

    Xu, Lihua; Wubbena, Zane; Stewart, Trae


    Purpose: The purpose of this paper is to investigate the factor structure and the measurement invariance of the Multifactor Leadership Questionnaire (MLQ) across gender of K-12 school principals (n=6,317) in the USA. Design/methodology/approach: Nine first-order factor models and four second-order factor models were tested using confirmatory…

  20. Arts Education as a Vehicle for Social Change: An Empirical Study of Eco Arts in the K-12 Classroom (United States)

    Sams, Jeniffer; Sams, Doreen


    Arts education has been part of the United States K-12 educational system for over a century. However, recent administrative policy decisions addressed the economic bottom line and the 1983 report, "A Nation at Risk," and complied with the "No Child Left Behind (NCLB) Act of 2001" (U.S. Department of Education, 2001). These…

  1. Evaluation of History Interest Inventory--Development and Evaluation of a History Interest Inventory for Chinese K-12 Students (United States)

    Dan, Yongjun; Wei, Tianlan; Zhao, Wenjun


    The purpose of this study was to develop and evaluate a History Interest Inventory (HII) to measure Chinese K-12 students' history interest. In this study, data were drawn from two independent samples of a city in Eastern China, and exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were conducted to reduce instrument size…

  2. Supporting Climate Literacy in the K12 Classroom by Identifying Educators' Perceived Barriers to and Gaps in Resources for Teaching Climate Change (United States)

    Tayne, K.


    As K12 teachers seek ways to provide meaningful learning opportunities for students to understand climate change, they often face barriers to teaching about climate and/or lack relevant resources on the topic. In an effort to better understand how to support K12 teachers in this role, a survey about "teaching climate change" was created and distributed. The results of the 2015 survey are presented, based on more than 200 teacher responses. Respondents included National Science Teachers Association (NSTA) members, 2015 STEM Teacher and Researcher (STAR) Fellows and science teachers from several U.S. school districts. The survey identifies teachers' perceived barriers to teaching climate change, for example difficulty integrating climate change concepts into specific core courses (i.e., biology), as well as desired classroom resources, such as climate change project-based learning (PBL) units that connect to the Next Generation Science Standards (NGSS). Survey results also indicate possible pathways for federal agencies, non-profits, universities and other organizations to have a more significant impact on climate literacy in the classroom. In response to the survey results, a comprehensive guide is being created to teach climate change in K12 classrooms, addressing barriers and providing resources for teachers. For example, in the survey, some teachers indicated that they lacked confidence in their content knowledge and understanding of climate change, so this guide provides web-based resources to help further an educator's understanding of climate change, as well as opportunities for relevant online and in-person professional development. In this quest for desired resources to teach climate change, gaps in accessible and available online resources are being identified. Information about these "gaps" may help organizations that strive to support climate literacy in the classroom better serve teachers.

  3. Evidence for significantly enhancing reduction of Azo dyes in Escherichia coli by expressed cytoplasmic Azoreductase (AzoA) of Enterococcus faecalis. (United States)

    Feng, J; Heinze, T M; Xu, H; Cerniglia, C E; Chen, H


    Although cytoplasmic azoreductases have been purified and characterized from various bacteria, little evidence demonstrating that these azoreductases are directly involved in azo dye reduction in vivo is known. In order to evaluate the contribution of the enzyme to azo dye reduction in vivo, experiments were conducted to determine the effect of a recombinant cytoplasmic azoreductase (AzoA) from Enterococcus faecalis expressed in Escherichia coli on the rate of metabolism of Methyl Red, Ponceau BS and Orange II. The intact cells that contained IPTG induced AzoA had a higher rate of dye reduction with increases of 2 (Methyl Red), 4 (Ponceau BS) and 2.6 (Orange II)-fold compared to noninduced cells, respectively. Metabolites of Methyl Red isolated from induced cultures were identified as N,N-dimethyl-p-phenylenediamine and 2-aminobenzoic acid through liquid chromatography electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) analyses. In conclusion, our data demonstrate that AzoA from Ent. faecalis is capable of increasing the reduction of azo dyes in intact E. coli cells and that cytoplasmic azoreductase is involved in bacterial dye degradation in vivo.

  4. 從課程學理基礎與核心素養論K-12 年級課程綱要A Research on Curriculum Theoretical Foundations and Key Competencies of K-12 Curriculum Guideline in

    Directory of Open Access Journals (Sweden)

    蔡清田Ching-Tien Tsai


    Full Text Available 本研究結合了研究者近年主持的兩件整合型研究計畫初步成果,包括國家教育研究院所委託執行的「K-12中小學一貫課程綱要核心素養與各領域之連貫體系研究」與「中小學課程相關之課程、教學、認知發展等學理基礎與理論趨向」,這些研究旨在建立我國未來幼兒教育、初等教育、前期中等教育及後期中等教育的「K-12年級課程綱要」之課程發展學理基礎,預備下一波課程改革。本文從核心素養與課程學理的教育哲學、教學理論、認知心理學、文化研究與社會變遷等角度切入,分析課程發展相關學理基礎,並依據課程學理與核心素養研究,對我國「K-12年級課程綱要」的基本理念、課程目標、核心素養、學習領域及實施通則等提出建議,冀能提升我國國民核心素養。 The main goal of this research aims to build theoretical foundations of curriculum development in order to prepare for the next curriculum reform regarding the K-12 curriculum guideline in Taiwan. So far as theoretical foundations of curriculum development is concerned, this research focuses on the relationships between key competencies and curriculum theoretical foundations regarding with five theoretical dimensions – educational philosophy, teaching theory, cognitive psychology, cultural studies and social change. First, the researcher analyses key competencies and theoretical foundations of curriculum development according to the literature review of the related curriculum theories and related studies. Second, the researcher builds up a set of theoretical foundations regarding curriculum development which is suitable for Taiwanese historical and cultural contexts. Finally, according to the new set of curriculum theoretical foundations, the researcher makes some suggestions for the future K-12 curriculum guidelines in Taiwan.

  5. "It's worth our time": a model of culturally and linguistically supportive professional development for K-12 STEM educators (United States)

    Charity Hudley, Anne H.; Mallinson, Christine


    Professional development on issues of language and culture is often separate from professional development on issues related to STEM education, resulting in linguistic and cultural gaps in K-12 STEM pedagogy and practice. To address this issue, we have designed a model of professional development in which we work with educators to build cultural and linguistic competence and to disseminate information about how educators view the relevance of language, communication, and culture to STEM teaching and learning. We describe the design and facilitation of our model of culturally and linguistically responsive professional development, grounded in theories of multicultural education and culturally supportive teaching, through professional development workshops to 60 K-12 STEM educators from schools in Maryland and Virginia that serve African American students. Participants noted that culturally and linguistically responsive approaches had yet to permeate their K-12 STEM settings, which they identified as a critical challenge to effectively teaching and engaging African-American students. Based on pre-surveys, workshops were tailored to participants' stated needs for information on literacy (e.g., disciplinary literacies and discipline-specific jargon), cultural conflict and mismatch (e.g., student-teacher miscommunication), and linguistic bias in student assessment (e.g., test design). Educators shared feedback via post-workshop surveys, and a subset of 28 participants completed in-depth interviews and a focus group. Results indicate the need for further implementation of professional development such as ours that address linguistic and cultural issues, tailored for K-12 STEM educators. Although participants in this study enumerated several challenges to meeting this need, they also identified opportunities for collaborative solutions that draw upon teacher expertise and are integrated with curricula across content areas.

  6. Open Educational Resources from Performance Task using Video Analysis and Modeling - Tracker and K12 science education framework


    Wee, Loo Kang


    This invited paper discusses why Physics performance task by grade 9 students in Singapore is worth participating in for two reasons; 1) the video analysis and modeling are open access, licensed creative commons attribution for advancing open educational resources in the world and 2) allows students to be like physicists, where the K12 science education framework is adopted. Personal reflections on how physics education can be made more meaningful in particular Practice 1: Ask Questions, Prac...

  7. An analysis of United States K-12 stem education versus STEM workforce at the dawn of the digital revolution (United States)

    Cataldo, Franca

    The world is at the dawn of a third industrial revolution, the digital revolution, that brings great changes the world over. Today, computing devices, the Internet, and the World Wide Web are vital technology tools that affect every aspect of everyday life and success. While computing technologies offer enormous benefits, there are equally enormous safety and security risks that have been growing exponentially since they became widely available to the public in 1994. Cybercriminals are increasingly implementing sophisticated and serious hack attacks and breaches upon our nation's government, financial institutions, organizations, communities, and private citizens. There is a great need for computer scientists to carry America's innovation and economic growth forward and for cybersecurity professionals to keep our nation safe from criminal hacking. In this digital age, computer science and cybersecurity are essential foundational ingredients of technological innovation, economic growth, and cybersecurity that span all industries. Yet, America's K-12 education institutions are not teaching the computer science and cybersecurity skills required to produce a technologically-savvy 21st century workforce. Education is the key to preparing students to enter the workforce and, therefore, American K-12 STEM education must be reformed to accommodate the teachings required in the digital age. Keywords: Cybersecurity Education, Cybersecurity Education Initiatives, Computer Science Education, Computer Science Education Initiatives, 21 st Century K-12 STEM Education Reform, 21st Century Digital Literacies, High-Tech Innovative Problem-Solving Skills, 21st Century Digital Workforce, Standardized Testing, Foreign Language and Culture Studies, Utica College, Professor Chris Riddell.

  8. Oral use of Streptococcus salivarius K12 in children with secretory otitis media: preliminary results of a pilot, uncontrolled study

    Directory of Open Access Journals (Sweden)

    Di Pierro F


    Full Text Available Francesco Di Pierro,1 Daniele Di Pasquale,2 Maurizio Di Cicco2 1Velleja Research, Milan, Italy; 2ORL Department, Ospedale Maggiore Policlinico Ca’ Grande IRCCS, Milan, Italy Abstract: Secretory otitis media (SOM remains a common disease among children. Although its cause is not yet perfectly established, the pathology, often a sequel of acute otitis media (AOM, is mainly characterized by persistent fluid in the middle ear cavity. Twenty-two children with a diagnosis of SOM were treated daily for 90 days with an oral formulation containing the oral probiotic Streptococcus salivarius K12 (Bactoblis®. After treatment, the children were evaluated for AOM episodes and subjected to tone audiometry, tympanometry, endonasal endoscopy, otoscopy, and tonsillar examination. Subject compliance and probiotic tolerability and side effects have also been evaluated. Our results indicate a good safety profile, a substantial reduction of AOM episodes, and a positive outcome from the treatment for all of the clinical outcomes tested. We conclude that strain K12 may have a role in reducing the occurrence and/or severity of SOM in children. From our perspective, this study constitutes a starting point toward the organization of a more extensive placebo-controlled study aimed at critically appraising our preliminary observations. Keywords: BLIS K12, Bactoblis®, acute otitis media, exudative otitis media

  9. Basic and applied uses of genome-scale metabolic network reconstructions of Escherichia coli

    DEFF Research Database (Denmark)

    McCloskey, Douglas; Palsson, Bernhard; Feist, Adam


    The genome-scale model (GEM) of metabolism in the bacterium Escherichia coli K-12 has been in development for over a decade and is now in wide use. GEM-enabled studies of E. coli have been primarily focused on six applications: (1) metabolic engineering, (2) model-driven discovery, (3) prediction...

  10. Evolution of Escherichia coli to 42 °C and Subsequent Genetic Engineering Reveals Adaptive Mechanisms and Novel Mutations

    DEFF Research Database (Denmark)

    Sandberg, Troy E.; Pedersen, Margit; LaCroix, Ryan A.


    Adaptive laboratory evolution (ALE) has emerged as a valuable method by which to investigate microbial adaptation to a desired environment. Here, we performed ALE to 42 °C of ten parallel populations of Escherichia coli K-12 MG1655 grown in glucose minimal media. Tightly controlled experimental...... reaffirmed the impact of the key mutations on the growth rate at 42 °C. Interestingly, most of the identified key gene targets differed significantly from those found in similar temperature adaptation studies, highlighting the sensitivity of genetic evolution to experimental conditions and ancestral genotype...

  11. Trends in Technology Planning and Funding in Florida K-12 Public Schools

    Directory of Open Access Journals (Sweden)



    Full Text Available This empirical research investigates trends in technology planning and funding in Florida’s K–12 public schools between the 2003–04 and 2005–06 academic years. Survey items that focused on funding and planning issues on Florida’s statewide school technology integration survey were analyzed using logistic models. Results indicate a significant increase in the number of schools revising their technology plans on a regular basis; a significant increase in the frequency with which Florida’s K–12 public schools are seeking funding for technology-related initiatives; a significant increase in parent, administrator, teacher, and student involvement in the technology planning process; and a significant decline in adequate funding for software and hardware needs. In addition, schools with low proportions of economically disadvantaged students sought and were awarded significantly more funds from donations and federal and state grants. Implications for educational leadership and policy are provided.

  12. Global functional atlas of Escherichia coli encompassing previously uncharacterized proteins.

    Directory of Open Access Journals (Sweden)

    Pingzhao Hu


    Full Text Available One-third of the 4,225 protein-coding genes of Escherichia coli K-12 remain functionally unannotated (orphans. Many map to distant clades such as Archaea, suggesting involvement in basic prokaryotic traits, whereas others appear restricted to E. coli, including pathogenic strains. To elucidate the orphans' biological roles, we performed an extensive proteomic survey using affinity-tagged E. coli strains and generated comprehensive genomic context inferences to derive a high-confidence compendium for virtually the entire proteome consisting of 5,993 putative physical interactions and 74,776 putative functional associations, most of which are novel. Clustering of the respective probabilistic networks revealed putative orphan membership in discrete multiprotein complexes and functional modules together with annotated gene products, whereas a machine-learning strategy based on network integration implicated the orphans in specific biological processes. We provide additional experimental evidence supporting orphan participation in protein synthesis, amino acid metabolism, biofilm formation, motility, and assembly of the bacterial cell envelope. This resource provides a "systems-wide" functional blueprint of a model microbe, with insights into the biological and evolutionary significance of previously uncharacterized proteins.

  13. Influence of CNTRENE(®) C100LM carbon nanotube material on the growth and regulation of Escherichia coli. (United States)

    Twibell, Brittany; Somerville, Kalie; Manani, Geoffrey; Duszynski, Molly; Wanekaya, Adam; Schweiger, Paul


    The growing use of carbon nanotubes (CNTs) in industrial and consumer products raises important questions about their environmental fate and impact on prokaryotes. In the environment, CNTs are exposed to a variety of conditions (e.g., UV light) that could lead to decomposition and changes in their chemical properties. Therefore, the potential cytotoxic effect of both pristine and artificially aged carboxyl functionalized CNTRENE(®) C100LM CNTmaterial at neutral and acidic conditions on Escherichia coli K12 was analyzed using a minimal inhibitory concentration (MIC) assay, which also allowed monitoring of non-lethal growth effects. However, there were no observable MIC or significant changes in growth behavior in E. coli K12 when exposed to pristine or aged CNTs. Exposure to pristine CNTRENE(®) C100LM CNT material did not appear to influence cell morphology or damage the cells when examined by electron microscopy. In addition, RNA sequencing revealed no observable regulatory changes in typical stress response pathways. This is surprising considering that previous studies have claimed high cytotoxicity of CNTs, including carboxyl functionalized single-walled CNTs, and suggest that other factors such as trace heavy metals or other impurities are likely responsible for many of the previously reported cytotoxicity in E. coli and possibly other microorganisms.

  14. Influence of CNTRENE® C100LM carbon nanotube material on the growth and regulation of Escherichia coli

    Directory of Open Access Journals (Sweden)

    Brittany Twibell


    Full Text Available The growing use of carbon nanotubes (CNTs in industrial and consumer products raises important questions about their environmental fate and impact on prokaryotes. In the environment, CNTs are exposed to a variety of conditions (e.g., UV light that could lead to decomposition and changes in their chemical properties. Therefore, the potential cytotoxic effect of both pristine and artificially aged carboxyl functionalized CNTRENE® C100LM CNTmaterial at neutral and acidic conditions on Escherichia coli K12 was analyzed using a minimal inhibitory concentration (MIC assay, which also allowed monitoring of non-lethal growth effects. However, there were no observable MIC or significant changes in growth behavior in E. coli K12 when exposed to pristine or aged CNTs. Exposure to pristine CNTRENE® C100LM CNT material did not appear to influence cell morphology or damage the cells when examined by electron microscopy. In addition, RNA sequencing revealed no observable regulatory changes in typical stress response pathways. This is surprising considering that previous studies have claimed high cytotoxicity of CNTs, including carboxyl functionalized single-walled CNTs, and suggest that other factors such as trace heavy metals or other impurities are likely responsible for many of the previously reported cytotoxicity in E. coli and possibly other microorganisms.

  15. Trends in Technology Planning and Funding in Florida K-12 Public Schools




    This empirical research investigates trends in technology planning and funding in Florida’s K–12 public schools between the 2003–04 and 2005–06 academic years. Survey items that focused on funding and planning issues on Florida’s statewide school technology integration survey were analyzed using logistic models. Results indicate a significant increase in the number of schools revising their technology plans on a regular basis; a significant increase in the frequency with which Florida’s K–12 ...

  16. Genomic and Phenomic Study of Mammary Pathogenic Escherichia coli (United States)

    Blum, Shlomo E.; Heller, Elimelech D.; Sela, Shlomo; Elad, Daniel; Edery, Nir; Leitner, Gabriel


    Escherichia coli is a major etiological agent of intra-mammary infections (IMI) in cows, leading to acute mastitis and causing great economic losses in dairy production worldwide. Particular strains cause persistent IMI, leading to recurrent mastitis. Virulence factors of mammary pathogenic E. coli (MPEC) involved pathogenesis of mastitis as well as those differentiating strains causing acute or persistent mastitis are largely unknown. This study aimed to identify virulence markers in MPEC through whole genome and phenome comparative analysis. MPEC strains causing acute (VL2874 and P4) or persistent (VL2732) mastitis were compared to an environmental strain (K71) and to the genomes of strains representing different E. coli pathotypes. Intra-mammary challenge in mice confirmed experimentally that the strains studied here have different pathogenic potential, and that the environmental strain K71 is non-pathogenic in the mammary gland. Analysis of whole genome sequences and predicted proteomes revealed high similarity among MPEC, whereas MPEC significantly differed from the non-mammary pathogenic strain K71, and from E. coli genomes from other pathotypes. Functional features identified in MPEC genomes and lacking in the non-mammary pathogenic strain were associated with synthesis of lipopolysaccharide and other membrane antigens, ferric-dicitrate iron acquisition and sugars metabolism. Features associated with cytotoxicity or intra-cellular survival were found specifically in the genomes of strains from severe and acute (VL2874) or persistent (VL2732) mastitis, respectively. MPEC genomes were relatively similar to strain K-12, which was subsequently shown here to be possibly pathogenic in the mammary gland. Phenome analysis showed that the persistent MPEC was the most versatile in terms of nutrients metabolized and acute MPEC the least. Among phenotypes unique to MPEC compared to the non-mammary pathogenic strain were uric acid and D-serine metabolism. This study

  17. National Sexuality Education Standards: Core Content and Skills, K-12. A Special Publication of the Journal of School Health. Special Report (United States)

    American School Health Association (NJ1), 2012


    The goal of this paper, "National Sexuality Education Standards: Core Content and Skills, K-12," is to provide clear, consistent and straightforward guidance on the "essential minimum, core content" for sexuality education that is developmentally and age-appropriate for students in grades K-12. The development of these standards is a result of an…

  18. Guided by Principles. Shaping the State of California's Role in K-12 Public School Facility Funding. Full Policy Research Working Paper (United States)

    Vincent, Jeffrey M.; Gross, Liz S.


    K-12 public school facilities need regular investment to ensure student health and safety and support educational programming. Yet, the future of K-12 school facility funding in California is uncertain. A strong state-local partnership has existed that funded new construction, modernization, and other investments in public school facilities across…


    This curriculum was developed as a significant component of the project, Always a River: The Ohio River and the American Experience, a six-state collaboration devoted to exploring the historical and cultural development of the Ohio River. The Always a River project is being joint...

  20. Sexual Harassment Policies in K-12 Schools: Examining Accessibility to Students and Content (United States)

    Lichty, Lauren F.; Torres, Jennifer M. C.; Valenti, Maria T.; Buchanan, NiCole T.


    Background: Peer sexual harassment is a significant social problem with consequences for both students and schools. Four out of 5 students report experiencing sexual harassment. These experiences have been linked to poor psychological health and academic withdrawal. Recognizing the seriousness of sexual harassment in schools, Supreme Court rulings…

  1. Consequences of Physical Health and Mental Illness Risks for Academic Achievement in Grades K-12 (United States)

    Joe, Sean; Joe, Emanique; Rowley, Larry L.


    Educational research, practice, and institutions regularly highlight the significance of factors outside of schooling that affect children's engagement and participation in classroom learning. The health of children and families is one such issue with implications for the quality of children's school experiences, treatment in school, and academic…

  2. Print to Braille: Preparation and Accuracy of Mathematics Materials in K-12 Education (United States)

    Herzberg, Tina S.; Rosenblum, L. Penny


    Introduction: This study analyzed the accuracy of 107 mathematics worksheets prepared for tactile learners. The mean number of errors was calculated, and we examined whether there was a significant difference in the level of accuracy based on National Library Service for the Blind and Physically Handicapped (NLS) certification or job role of…

  3. K-12 Virtual Students: Relationships between Student Demographics, Virtual Learning Experience, and Academic Achievement (United States)

    Whitinger, Jamie Hilton


    The purpose of this study was to identify significant differences in academic achievement among virtual students of various backgrounds, demographics, and virtual learning environments. The study also sought to identify factors that may predict the academic achievement, as defined by final course grade, of virtual students. This study examined…

  4. Integrating local environmental research into K-12 science classrooms and the value of graduate student-educator partnerships (United States)

    Ward, N. D.; Petrik-Finley, R.


    Collaboration between researchers and K-12 educators enables an invaluable exchange of teaching philosophies and educational tools. Programs that partner graduate students with K-12 educators serve the dual purpose of training future educators and providing K-12 students with unique opportunities and perspectives. The benefits of this type of partnership include providing students with enhanced educational experiences and positive student-mentor relationships, training STEM graduate students in effective teaching strategies, and providing teachers with a firsthand resource for scientific information and novel educational materials. Many high school students have had little exposure to science beyond the classroom. Frequent interactions with "real-life" scientists can help make science more approachable and is an effective strategy for promoting science as a career. Here I describe my experiences and several lessons designed as a NSK GK-12 fellow. For example, a month-long unit on biogeochemical principles was framed as a crime scene investigation of a fish kill event in Hood Canal, Washington, in which students were given additional pieces of evidence to solve the mystery as they satisfied checkpoints in their understanding of key concepts. The evidence pieces included scientific plots, maps, datasets, and laboratory exercises. A clear benefit of this investigation-style unit is that students were able to learn the material at their individual pace. This structure allowed for a streamlined integration of differentiated materials such as simplified background readings or visual learning aids for struggling students or more detailed news articles and primary literature for more advanced students. Although the NSF GK-12 program has been archived, educators and researchers should pursue new partnerships, leveraging local and state-level STEM outreach programs with the goal of increasing national exposure of the societal benefits of such synergistic activities.

  5. A rising tide floats all boats: increasing scientific literacy through collaboration between scientists and K-12 educators (United States)

    Helmuth, B.; Schneider, K. R.


    Interactions between research scientists and K-12 educator are all too often viewed as a one-way transfer of information, from researcher to teacher. We describe two models that increase the scientific literacy of K-12 teachers and students, and also work to enhance the communication skills of graduate and undergraduate students. In the first model ('The Rising Tide' as well as similar programs funded by NSF RET and REU), teachers are paired with faculty, undergraduate and graduate students during the summer and fall. Each team conduct research projects, writes lesson plans based on current scientific research and on national standards, and tests the efficacy of lessons in a classroom environment. Teachers acquire content knowledge while enhancing skills in reasoning, communication, and creativity as they develop a broader understanding of their fields of study. Scientists and students gain help with scientific research, and develop effective communication skills that help to bridge the gap between academia and a diversity of nonscientific audiences. The second model sends scientists into the classrooms to work with teachers and students through programs such as TIPS and NSF GK-12. The scientists serve as co-teachers and mentors conducting individual lessons, creating and updating curriculum, and developing new pedagogies for incorporating stronger science inquiry. Scientists gain a greater appreciation for K-12 education while enhancing their own teaching and collaboration skills. We will describe ways to develop these types of programs, the strengths and weaknesses of both models, roles of all the participants, as well as reflections from participant surveys and personal experiences. Crucially, we view these not as 'trainee teaching the trainer' models, but as true collaborations between professionals.

  6. The Air Force Academy’s Falcon Telescope Network: An Educational and Research Network for K-12 and Higher Education (United States)

    Chun, Francis; Tippets, Roger; Della-Rose, Devin J.; Polsgrove, Daniel; Gresham, Kimberlee; Barnaby, David A.


    The Falcon Telescope Network (FTN) is a global network of small aperture telescopes developed by the Center for Space Situational Awareness Research in the Department of Physics at the United States Air Force Academy (USAFA). Consisting of commercially available equipment, the FTN is a collaborative effort between USAFA and other educational institutions ranging from two- and four-year colleges to major research universities. USAFA provides the equipment (e.g. telescope, mount, camera, filter wheel, dome, weather station, computers and storage devices) while the educational partners provide the building and infrastructure to support an observatory. The user base includes USAFA along with K-12 and higher education faculty and students. The diversity of the users implies a wide variety of observing interests, and thus the FTN collects images on diverse objects, including satellites, galactic and extragalactic objects, and objects popular for education and public outreach. The raw imagery, all in the public domain, will be accessible to FTN partners and will be archived at USAFA. USAFA cadets use the FTN to continue a tradition of satellite characterization and astronomical research; this tradition is the model used for designing the network to serve undergraduate research needs. Additionally, cadets have led the development of the FTN by investigating observation priority schemes and conducting a 'day-in-the-life' study of the FTN in regards to satellite observations. With respect to K-12 outreach, cadets have provided feedback to K-12 students and teachers through evaluation of first-light proposals. In this paper, we present the current status of the network and results from student participation in the project.

  7. CALiPER Report 21.1. Linear (T8) Lamps in a 2x4 K12-Lensed Troffer

    Energy Technology Data Exchange (ETDEWEB)



    This report focuses on the performance of the same 31 linear LED lamps operated in a typical troffer with a K12 prismatic lens. In general, luminaire efficacy is strongly dictated by lamp efficacy, but the optical system of the luminaire substantially reduces the differences between the luminous intensity distributions of the lamps. While the distributions in the luminaire are similar, the differences remain large enough that workplane illuminance uniformity may be reduced if linear LED lamps with a narrow distribution are used. At the same time, linear LED lamps with a narrower distribution result in slightly higher luminaire efficiency.

  8. Adventures in supercomputing, a K-12 program in computational science: An assessment

    Energy Technology Data Exchange (ETDEWEB)

    Oliver, C.E.; Hicks, H.R. [Oak Ridge National Lab., TN (United States); Iles-Brechak, K.D. [Vanderbilt Univ., Oak Ridge, TN (United States); Honey, M.; McMillan, K. [Education Development Center, New York, NY (United States)


    In this paper, the authors describe only those elements of the Department of Energy Adventures in Supercomputing (AiS) program for high school teachers, such as school selection, which have a direct bearing on assessment. Schools submit an application to participate in the AiS program. They propose a team of at least two teachers to implement the AiS curriculum. The applications are evaluated by selection committees in each of the five participating states to determine which schools are the most qualified to carry out the program and reach a significant number of women, minorities, and economically disadvantaged students, all of whom have historically been underrepresented in the sciences. Typically, selected schools either have a large disadvantaged student population, or the applying teachers propose specific means to attract these segments of their student body into AiS classes. Some areas with AiS schools have significant numbers of minority students, some have economically disadvantaged, usually rural, students, and all areas have the potential to reach a higher proportion of women than technical classes usually attract. This report presents preliminary findings based on three types of data: demographic, student journals, and contextual. Demographic information is obtained for both students and teachers. Students have been asked to maintain journals which include replies to specific questions that are posed each month. An analysis of the answers to these questions helps to form a picture of how students progress through the course of the school year. Onsite visits by assessment professionals conducting student and teacher interviews, provide a more in depth, qualitative basis for understanding student motivations.

  9. The use of Global Positioning System units and ArcGIS Online to engage K-12 Students in Research Being Done in their Local Communities (United States)

    Butcher, C. E.; Sparrow, E. B.; Clucas, T.


    Incorporating K-12 students in scientific research processes and opportunities in their communities is a great way to bridge the gap between research and education and to start building science research capacity at an early age. One goal of the Experimental Program to Stimulate Competitive Research (EPSCoR) Alaska Adapting to Changing Environments project is to engage the local community in the research as well as to share results with the people. By giving K-12 students Global Positioning System (GPS) units, and allowing them to collect and map their own data, they are being exposed to some of the research methods being used by scientists in the Alaska ACE project. This hands-on, minds-on method has been successfully used in formal education settings such as a Junior High School classroom in Nuiqsut, Alaska as well as in informal education settings such as summer camps in Barrow, Alaska and Kenai, Alaska. The students progress from mapping by hand to collecting location data with their GPS units and cameras, and imputing this information into ArcGIS Online to create map products. The data collected were from sites ranging from important places in the community to sites visited during summer camps, with students reflecting on data and site significance. Collecting data, using technology, and creating map products contribute to science skills and practices students need to conduct research of their own and to understand research being done around them. The goal of this education outreach implementation is to bring students closer to the research, understand the process of science, and have the students continue to collect data and contribute to research in their communities. Support provided for this work from the Alaska EPSCoR NSF Award #OIA-1208927 and the state of Alaska is gratefully acknowledged.

  10. Einstein Online: A Web-based Course for K-12 Teachers from the American Museum of Natural History (United States)

    Steiner, Robert


    Einstein Online: A Web-based Course for K-12 Teachers from the American Museum of Natural History Robert V. Steiner, Ph.D. Project Director, Seminars on Science American Museum of Natural History The American Museum of Natural History, in collaboration with Hebrew University and the Skirball Cultural Center, has created a major exhibit on Albert Einstein, including extensive coverage of his contributions to relativity, quantum mechanics and unified field theories as well as the social and political dimensions of his life. Leveraging the assets of this exhibit as well as the expertise of the Museum's Department of Astrophysics and its Education Department, a six-week online professional development course for K-12 teachers has been created, providing inquires into some of the frontiers of physics through rich media resources, facilitated discussion forums and assignments. The course, which requires only minimal Web access, offers a unique opportunity for teachers across the United States to explore modern physics guided by a working scientist and a skilled online facilitator. The course includes original essays by Museum scientists, images, video, simulations, web links and digital resources for classroom use. The course design, development, implementation and evaluation are reviewed.

  11. Adventure Learning Through Water and MOSS - a novel approach to engaging K-12 students in climate change issues (United States)

    Eitel, K.; Miller, B.; Veletsianos, G.; Eitel, J.; O'Hair, M.; Schon, J.; Hougham, R. J.


    Climate change is projected to affect the distribution and availability of water resources at the local and global scale. In an effort to educate K-12 students about water resources in a changing climate the Adventure learning through Water and MOSS project was created. This project is engaging K-12 students throughout Idaho with meaningful inquiries into water resource issues through outdoor data-collection expeditions supported via a novel online learning environment ( Students collect authentic data related to an inquiry-based curriculum and data are shared within the online environment. Students, teachers, and content experts from throughout Idaho then communicate and collaborate in meaningful ways around data using the online environment and the latest in communication technologies. The McCall Outdoor Science School (MOSS) collaborates as an informal science education provider and cornerstone to the project mission by serving as the base camp for water expeditions. Water expeditions are inquiry-driven and focus on various aspects of water resources within a changing climate.

  12. Solar Schools Assessment and Implementation Project: Financing Options for Solar Installations on K-12 Schools

    Energy Technology Data Exchange (ETDEWEB)

    Coughlin, J.; Kandt, A.


    This report focuses on financial options developed specifically for renewable energy and energy efficiency projects in three California public school districts. Solar energy systems installed on public schools have a number of benefits that include utility bill savings, reductions in greenhouse gas emissions (GHGs) and other toxic air contaminants, job creation, demonstrating environmental leadership, and creating learning opportunities for students. In the 2011 economic environment, the ability to generate general-fund savings as a result of reducing utility bills has become a primary motivator for school districts trying to cut costs. To achieve meaningful savings, the size of the photovoltaic (PV) systems installed (both individually on any one school and collectively across a district) becomes much more important; larger systems are required to have a material impact on savings. Larger PV systems require a significant financial commitment and financing therefore becomes a critical element in the transaction. In simple terms, school districts can use two primary types of ownership models to obtain solar installations and cost savings across a school district. The PV installations can be financed and owned directly by the districts themselves. Alternatively, there are financing structures whereby another entity, such as a solar developer or its investors, actually own and operate the PV systems on behalf of the school district. This is commonly referred to as the 'third-party ownership model.' Both methods have advantages and disadvantages that should be weighed carefully.

  13. A Case Study: School Climate Results of a Private K-12 School Chain

    Directory of Open Access Journals (Sweden)

    Sinem Vatanartıran


    Full Text Available School climate can vary from school to school within the same district and an individual school can develop a climate independently of the larger organization. The research question is whether schools that operate under the same school chain show similar or different school environment factors with regards to parents, students, and teachers. This is a case study where data is collected quantitatively. The case was selected by using purposeful sampling method. 3 of the elementary schools in this school chain located in the same city were included into this study. To collect data, Learning Environments Survey was used. There are 7 factors in the survey: Satisfaction, Principal’s Leadership, Effective Communication, Service Satisfaction, Identity, and Climate. To analyze data, one-way ANOVA and descriptive statistics were done. The analysis of the surveys administered to parents, students, and teachers showed significant differences in the factors of Principal and Communication amongst teachers, Academic Satisfaction, Communication, and Identity amongst students, and Identity amongst parents.

  14. A phenomenological case study concerning science teacher educators' beliefs and teaching practices about culturally relevant pedagogy and preparing K-12 science teachers to engage African American students in K-12 science (United States)

    Underwood, Janice Bell

    Due to the rising diversity in today's schools, science teacher educators (STEs) suggest that K-12 teachers must be uniquely prepared to engage these students in science classrooms. Yet, in light of the increasing white-black science achievement gap, it is unclear how STEs prepare preservice teachers to engage diverse students, and African Americans in particular. Therefore, the purpose of this study was to find out how STEs prepare preservice teachers to engage African American students in K-12 science. Thus, using the culturally relevant pedagogy (CRP) framework, this phenomenological case study explored beliefs about culturally relevant science teaching and the influence of reported beliefs and experiences related to race on STEs' teaching practices. In the first phase, STE's in a mid-Atlantic state were invited to participate in an electronic survey. In the second phase, four participants, who were identified as exemplars, were selected from the survey to participate in three semi-structured interviews. The data revealed that STEs were more familiar with culturally responsive pedagogy (CResP) in the context of their post-secondary classrooms as opposed to CRP. Further, most of the participants in part one and two described modeling conventional ways they prepare their preservice teachers to engage K-12 students, who represent all types of diversity, without singling out any specific race. Lastly, many of the STEs' in this study reported formative experiences related to race and beliefs in various manifestations of racism have impacted their teaching beliefs and practices. The findings of this study suggest STEs do not have a genuine understanding of the differences between CRP and CResP and by in large embrace CResP principles. Secondly, in regards to preparing preservice teachers to engage African American students in science, the participants in this study seemed to articulate the need for ideological change, but were unable to demonstrate pedagogical changes

  15. The Arctic Climate Modeling Program: K-12 Geoscience Professional Development for Rural Educators (United States)

    Bertram, K. B.


    Helping teachers and students connect with scientists is the heart of the Arctic Climate Modeling Program (ACMP), funded from 2005-09 by the National Science Foundation’s Innovative Technology Experience for Students and Teachers. ACMP offered progressive yearlong science, technology and math (STM) professional development that prepared teachers to train youth in workforce technologies used in Arctic research. ACMP was created for the Bering Strait School District, a geographically isolated area with low standardized test scores, high dropout rates, and poverty. Scientists from around the globe have converged in this region and other areas of the Arctic to observe and measure changes in climate that are significant, accelerating, and unlike any in recorded history. Climate literacy (the ability to understand Earth system science and to make scientifically informed decisions about climate changes) has become essential for this population. Program resources were designed in collaboration with scientists to mimic the processes used to study Arctic climate. Because the Bering Strait School District serves a 98 percent Alaska Native student population, ACMP focused on best practices shown to increase the success of minority students. Significant research indicates that Alaska Native students succeed academically at higher rates when instruction addresses topics of local interest, links education to the students’ physical and cultural environment, uses local knowledge and culture in the curriculum, and incorporates hands-on, inquiry-based lessons in the classroom. A seven-partner consortium of research institutes and Alaska Native corporations created ACMP to help teachers understand their role in nurturing STM talent and motivating students to explore geoscience careers. Research underscores the importance of increasing school emphasis in content areas, such as climate, that facilitate global awareness and civic responsibility, and that foster critical thinking and

  16. Genome-wide profiling of histone modifications (H3K9me2 and H4K12ac) and gene expression in rust (uromyces appendiculatus) inoculated common bean (Phaseolus vulgaris L)


    Ayyappan, Vasudevan; Kalavacharla, Venu (Kal); Thimmapuram, Jyothi; Bhide, Ketaki P; Sripathi, Venkateswara R.


    Histone modifications such as methylation and acetylation play a significant role in controlling gene expression in unstressed and stressed plants. Genome-wide analysis of such stress-responsive modifications and genes in non-model crops is limited. We report the genome-wide profiling of histone methylation (H3K9me2) and acetylation (H4K12ac) in common bean (Phaseolus vulgaris L.) under rust (Uromyces appendiculatus) stress using two high-throughput approaches, chromatin immunoprecipitation s...

  17. First Steps Toward K-12 Teacher Professional Development Using Internet-based Telescopes (United States)

    Berryhill, K. J.; Gershun, D.; Slater, T. F.; Armstrong, J. D.

    2012-12-01, Faulkes Telescope North (FTN—part of Las Cumbres Observatory Global Telescope Network—, and the MicroObservatory Robotic Telescope Network ( As is common in astronomy observation, the class experienced setbacks to observing plans from a variety of sources, including clouds, dust storms, wind, instrument malfunctions, and light pollution from a nearby rodeo. Participants requested observations on robotic telescopes and directly controlled remote telescopes (FTN and Sky Titan). Data from the surveys suggest the theme that the ability to control telescopes in real time is of significant educational value, despite 6 of 10 participants citing frustrations due to equipment malfunctions and weather. Future courses will need backup plans or dates to account for the possibility of lost observing time. Participants used a variety of software tools to analyze data. Survey data showed the LCOGT Agent Exoplanet citizen science exercise to be an important learning event in the progression toward using SalsaJ to create exoplanet light curves from FTN data. Much of the data from FTN and Sky Titan used by participants was not collected during the observing runs due to issues noted above. The telescope operators provided previous data for analysis. None of the evidence we collected indicates that this lack of direct linkage is a problem.

  18. How should we teach diverse students? Cross-cultural comparison of diversity issues in K-12 schools in Japan and the US

    Directory of Open Access Journals (Sweden)

    Fuyu Shimomura


    Full Text Available Increasing student diversity in K-12 schools has gained attention in Japan and the US. In the US, racial diversity has historically shaped inequity in educational access and teacher quality. In Japan, regardless of its reputation for cultural homogeneity among its residents, issues surrounding student diversity have gained attention because of the increasing number of returnees—Japanese students raised overseas because of their parents’ expatriation. This paper compares and contrasts the diversity issues in K-12 school settings in both countries, and explores potential approaches to improve the accommodation of diversity in K-12 schools.

  19. Ocean Science in a K-12 setting: Promoting Inquiry Based Science though Graduate Student and Teacher Collaboration (United States)

    Lodico, J. M.; Greely, T.; Lodge, A.; Pyrtle, A.; Ivey, S.; Madeiros, A.; Saleem, S.


    The University of South Florida, College of Marine Science Oceans: GK-12 Teaching Fellowship Program is successfully enriching science learning via the oceans. Funded by the National Science Foundation, the program provides a unique opportunity among scientists and K-12 teachers to interact with the intention of bringing ocean science concepts and research to the classroom environment enhance the experience of learning and doing science, and to promote `citizen scientists' for the 21st century. The success of the program relies heavily on the extensive summer training program where graduate students develop teaching skills, create inquiry based science activities for a summer Oceanography Camp for Girls program and build a relationship with their mentor teacher. For the last year and a half, two graduate students from the College of Marine Science have worked in cooperation with teachers from the Pinellas county School District, Southside Fundamental Middle School. Successful lesson plans brought into a 6th grade Earth Science classroom include Weather and climate: Global warming, The Geologic timescale: It's all about time, Density: Layering liquids, and Erosion processes: What moves water and sediment. The school and students have benefited greatly from the program experiencing hands-on inquiry based science and the establishment of an after school science club providing opportunities for students to work on their science fair projects and pursuit other science interests. Students are provided scoring rubrics and their progress is creatively assessed through KWL worksheets, concept maps, surveys, oral one on one and classroom discussions and writing samples. The year culminated with a series of hands on lessons at the nearby beach, where students demonstrated their mastery of skills through practical application. Benefits to the graduate student include improved communication of current science research to a diverse audience, a better understanding of the

  20. Extending the Pathway: Building on a National Science Foundation Workforce Development Project for Underserved k-12 Students (United States)

    Slattery, W.; Smith, T.


    With new career openings in the geosciences expected and a large number of presently employed geoscientists retiring in the next decade there is a critical need for a new cadre of geoscientists to fill these positions. A project funded by the National Science Foundation titled K-12 Students, Teachers, Parents, Administrators and Higher Education Faculty: Partners Helping Rural Disadvantaged Students Stay on the Pathway to a Geoscience Career involving Wright State University and the Ripley, Lewis, Union, Huntington k-12 school district in Appalachian Ohio took led to dozens of seventh and eighth grade students traveling to Sandy Hook, New Jersey for a one week field experience to study oceanography with staff of the New Jersey Sea Grant Consortium. Teachers, parent chaperones, administrators and university faculty accompanied the students in the field. Teachers worked alongside their students in targeted professional development during the weeklong field experience. During the two academic years of the project, both middle school and high school teachers received professional development in Earth system science so that all students, not just those that were on the summer field experience could receive enhanced science learning. All ninth grade high school students were given the opportunity to take a high school/college dual credit Earth system science course. Community outreach provided widespread knowledge of the project and interest among parents to have their children participate. In addition, ninth grade students raised money themselves to fund a trip to the International Field Studies Forfar Field Station on Andros Island, Bahamas to study a tropical aquatic system. Students who before this project had never traveled outside of Ohio are currently discussing ways that they can continue on the pathway to a geoscience career by applying for internships for the summer between their junior and senior years. These are positive steps towards taking charge of their

  1. K12N METAR (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — METAR is a routine scheduled observation and is the primary observation code used in the United States to satisfy requirements for reporting surface meteorological...

  2. Escherichia coli (United States)

    Alizade, Hesam


    Escherichia coli is the most prominent cause of infectious diseases that span from the gastrointestinal tract to extra-intestinal sites such as urinary tract infection, septicaemia, and neonatal meningitis. The emergence and spread of antibiotic resistance in E. coli is an increasing public health concern across the world. Rising resistance in E. coli isolates is also observed in Iran. This review summarizes the status of antibiotic resistance of E. coli isolates in Iran from 2007 to 2016. The data of the prevalence of E. coli antibiotic resistance were collected from databases such as Web of Science, PubMed, Scopus, Embase, Cochrane Library, Google Scholar and Scientific Information Database. Antibiotic resistance in E. coli is on the rise. Prevalence of antibiotic resistance of E. coli varies from region to region in Iran.

  3. Organizational Policies and Programs to Reduce Job Stress and Risk of Workplace Violence Among K-12 Education Staff. (United States)

    Landsbergis, Paul; Zoeckler, Jeanette; Kashem, Zerin; Rivera, Bianca; Alexander, Darryl; Bahruth, Amy


    We examine strategies, programs, and policies that educators have developed to reduce work stressors and thus health risks. First, we review twenty-seven empirical studies and review papers on organizational programs and policies in K-12 education published from 1990 to 2015 and find some evidence that mentoring, induction, and Peer Assistance and Review programs can increase support, skill development, decision-making authority, and perhaps job security, for teachers-and thus have the potential to reduce job stressors. Second, we describe efforts to reduce workplace violence in Oregon, especially in special education, including legislation, collective bargaining, research, and public awareness. We conclude that to reduce workplace violence, adequate resources are needed for staffing, training, equipment, injury/assault reporting, and investigation. Third, we discuss collective bargaining initiatives that led to mentoring and Peer Assistance and Review and state legislation on prevention of bullying and harassment of school staff. Finally, we present a research agenda on these issues.

  4. The Delicate Balance between Research, Teaching and Outreach: A Case Study of Physicists in K-12 Education (United States)

    Leslie-Pelecky, Diandra


    Recent calls from a variety of sectors including some funding agencies and professional societies encourage physicists to take a more active interest in the education of K-12 students and their teachers. Although there are a broad range of possible activities, finding time to participate is always a challenge for the researcher. How does the busy physicist ensure that the time devoted to education or outreach activities produces meaningful results without adversely affecting his or her research program? Project Fulcrum, a NSF-funded program that teams science and math graduate students at the University of Nebraska-Lincoln with 4th -8th grade teachers in the Lincoln Public Schools, presents a case study of how research scientists can be meaningfully involved with K-12 education. Project Fulcrum's preliminary results indicate that the impact scientists have in the classroom goes far beyond providing expertise in physics, and turns out to be very different than originally anticipated. There are a wide variety of models for involvement in education and outreach that cover a broad span of time and energy commitments. Careful project choice, establishing administrative infrastructure, collaborating with other departments and colleges, and involving colleagues can optimize the impact-made-to-time-spent ratio. Challenges such as project evaluation, overcoming the negative attitudes of some physicists towards anything not related to research, and ensuring that participants get appropriate credit for their efforts will also be discussed. The conclusion will address the personal and professional rewards of involvement in education and outreach. This work is funded by the National Science Foundation (NSF-DGE0086358). The author wishes to acknowledge the contributions of co-PIs G. Buck, S. Kirby, R. Kirby and P. Dussault, and all of the Project Fulcrum Fellows and Teachers.

  5. A View from the Trenches: What Teachers Say About Earth and Space Science Education in the K-12 Classroom Today (United States)

    Johnson, R. M.; Herrold, A.; Holzer, M. A.; Passow, M. J.


    A casual glance at the headlines on almost any day of the week regularly makes clear that we live on a dynamic and at times unpredictable planet. The processes underway within the Earth system, and the impact of external influences from space, can have dramatic and terrible consequences for life on Earth. Given the scope and power of these processes, the need for a citizenry that understands the behavior of the Earth and its environment seems like a "no-brainer". Nonetheless, ESS educators across the country are facing daunting challenges, which are becoming even more critical in a time of severely diminished education funding. In many states/districts, ESS courses at the secondary level are under threat, and Earth and space science education is in crisis. Many universities do not accept ESS as a "lab" course, producing repercussions throughout K-12 science education. ESS is addressed very differently in states and districts across the country. In some districts where ESS was a required high school course, the requirement is being dropped, and courses changed to an elective or removed entirely from the curriculum. In other districts, ESS is disappearing from the middle school curriculum. In some districts, administrators recognize the need to have students understand ESS to meet state educational standards in the Earth sciences, and are requiring ESS for all students in high school. In a few states, districts recognize the interdisciplinary nature of ESS and are moving it into a high-level, challenging capstone science course - in some cases tied to credit at the university level. This presentation will provide an overview of results of a recent survey of K-12 Earth and space science educators conducted by the National Earth Science Teachers Association on their needs, concerns, and trends in Earth and space science education in their districts.

  6. High incidence of multiple antibiotic resistant cells in cultures of in enterohemorrhagic Escherichia coli O157:H7


    Carone, Benjamin R.; Xu, Tao; Murphy, Kenan C.; Marinus, Martin G.


    The spontaneous incidence of chloramphenicol (Cam) resistant mutant bacteria is at least ten-fold higher in cultures of enterohemorrhagic E. coli O157:H7 strain EDL933 than in E. coli K-12. It is at least 100-fold higher in the dam (DNA adenine methyltransferase) derivative of EDL933, compared to the dam strain of E. coli K-12, thereby preventing the use of Cam resistance as a marker in gene replacement technology. Genome sequencing of Cam-resistant isolates of EDL933 and its dam derivatives ...

  7. Sustainable Materials Management (SMM) Web Academy Webinar: Changing How We Think About Our Resources for a Better Tomorrow: How to Donate Surplus Food from K-12 Schools (United States)

    This is a webinar page for the Sustainable Management of Materials (SMM) Web Academy webinar titled Changing How We Think About Our Resources for a Better Tomorrow: How to Donate Surplus Food from K-12 Schools

  8. Use of Adaptive Laboratory Evolution To Discover Key Mutations Enabling Rapid Growth of Escherichia coli K-12 MG1655 on Glucose Minimal Medium

    DEFF Research Database (Denmark)

    LaCroix, Ryan A.; Sandberg, Troy E.; O'Brien, Edward J.


    often mutated: the global transcription gene rpoB, an 82-bp deletion between the metabolic pyrE gene and rph, and an IS element between the DNA structural gene hns and tdk. Model-derived classification of gene expression revealed a number of processes important for increased growth that were missed...

  9. Potential antitumour mitosenes: relationship between in vitro DNA interstrand cross-link formation and DNA damage in escherichia coli K-12 strains

    NARCIS (Netherlands)

    Maliepaard, Marc; Sitters, Karin A.M.C.; de Mol, Nico J.; Janssen, Lambert H.M.; Stratford, Ian J.; Stephens, Miriam; Verboom, Willem; Reinhoudt, David


    This investigation was aimed at determining the possible relationship between DNA interstrand cross-linking and the cytotoxic activity of potential antitumour mitosene compounds. Mitosenes, possessing two good leaving groups at C-1 and C-10, were found to be able to cross-link calf thymus DNA under

  10. A combined treatment of UV-light and radio frequency electric field for the inactivation of Escherichia coli K-12 in apple juice (United States)

    Radio frequency electric fields (RFEF) and UV-light treatments have been reported to inactivate bacteria in liquid foods. However, information on the efficacy of bacterial inactivation by combined treatments of RFEF and UV-light technologies is limited. In this study, we investigated the relationshi...

  11. Role of Rom protein in copy number control of plasmid pBR322 at different growth rates in Escherichia coli K-12

    DEFF Research Database (Denmark)

    Tove, Atlung; Christensen, Bjarke Bak; Hansen, Flemming G.


    The copy number per cell mass of plasmid pBR322 and a rom(-) derivative was measured as a function of generation time. In fast growing cells the copy number per cell mass was virtually identical for rom(+) and rom(-) derivatives. However, the copy number of pBR322 only increased 3- to 4-fold from...... a 20- to 80-min generation time, whereas the copy number of the torn derivative increased 7- to 10-fold. The copy number stayed constant for the rom(+) and rom(-) plasmids at generation times longer than 80-100 min. Thus, the presence of the rom gene decreased the copy number of plasmid pBR322...... in slowly growing cells at least 2-fold when compared with the rom(-) plasmid. To study the effect of the rom gene in trans we cloned the gene into the compatible P15A-derived rom(-) plasmid pACYC184. In cells carrying both pACYC184 rein; and pBR322 rom(-) the presence of the rom gene in trans had little...

  12. Repression of the aroF promoter by the TyrR repressor in Escherichia coli K-12: role of the 'upstream' operator site. (United States)

    Cobbett, C S


    Three sequences are required for complete repression of the aroF promoter by the TyrR repressor protein. Two of these operator sites lie adjacent to each other and overlap the -35 region of the aroF promoter while the third lies about 70 base pairs upstream of the promoter. An aroF-cat (chloramphenicol acetyltransferase) gene fusion has been used to assay the effect of DNA insertions that alter the distance between the two promoter-proximal and the third, distal, operator sites on the repression of the aroF promoter in vivo. The distal site contributes to the repression of the promoter up to a distance of about 400 base pairs and its effect is not dependent on its separation from the first and second sites by an integral number of turns of the DNA helix.

  13. Thymine utilization in Escherichia coli K12. On the role of deoxyribose 1-phosphate and thymidine phosphorylase

    DEFF Research Database (Denmark)

    Jensen, Kaj Frank; Leer, Johan Christian; Nygaard, Per


    to be presented in this paper indicate that the ability of different thymine auxotrophs to grow on progressively lower thymine concentrations is a function of their capacity to increase the internal pool of deoxyribose 1-phosphate and/or the level of thymidine phosphorylase. Thymine incorporation in wild...... to the external thymine concentration. The experiments in vivo led us to conclude that the incorporation of exogenous thymine occurs via thymidine, which is synthesized from thymine and deoxyribose 1-phosphate, catalyzed by thymidine phosphorylase. In accordance with this studies in vitro with purified thymidine...

  14. Involvement of the gapA- and epd (gapB)-encoded dehydrogenases in pyridoxal 5'-phosphate coenzyme biosynthesis in Escherichia coli K-12. (United States)

    Yang, Y; Zhao, G; Man, T K; Winkler, M E


    We show that epd (gapB) mutants lacking an erythrose 4-phosphate (E4P) dehydrogenase are impaired for growth on some media and contain less pyridoxal 5'-phosphate (PLP) and pyridoxamine 5'-phosphate (PMP) than their epd+ parent. In contrast to a previous report, we found that gapA epd double mutants lacking the glyceraldehyde 3-phosphate and E4P dehydrogenases are auxotrophic for pyridoxine. These results implicate the GapA and Epd dehydrogenases in de novo PLP and PMP coenzyme biosynthesis.

  15. Involvement of the gapA- and epd (gapB)-Encoded Dehydrogenases in Pyridoxal 5′-Phosphate Coenzyme Biosynthesis in Escherichia coli K-12 (United States)

    Yang, Yong; Zhao, Genshi; Man, Tsz-Kwong; Winkler, Malcolm E.


    We show that epd (gapB) mutants lacking an erythrose 4-phosphate (E4P) dehydrogenase are impaired for growth on some media and contain less pyridoxal 5′-phosphate (PLP) and pyridoxamine 5′-phosphate (PMP) than their epd+ parent. In contrast to a previous report, we found that gapA epd double mutants lacking the glyceraldehyde 3-phosphate and E4P dehydrogenases are auxotrophic for pyridoxine. These results implicate the GapA and Epd dehydrogenases in de novo PLP and PMP coenzyme biosynthesis. PMID:9696782

  16. The CytR repressor antagonizes cyclic AMP-cyclic AMP receptor protein activation of the deoCp2 promoter of Escherichia coli K-12

    DEFF Research Database (Denmark)

    Søgaard-Andersen, L; Martinussen, J; Møllegaard, N E


    AMP-CRP complex; (iii) introduction of point mutations in either CRP target resulted in loss of CytR regulation; and (iv) regulation by CytR of deletion mutants lacking CRP-2 could be specifically reestablished by increasing the intracellular concentration of CytR. These findings indicate that both CRP targets...

  17. Diarrheagenic Escherichia coli Markers and Phenotypes among Fecal E. coli Isolates Collected from Nicaraguan Infants ▿


    Reyes, Daniel; Vilchez, Samuel; Paniagua, Margarita; Colque-Navarro, Patricia; Weintraub, Andrej; Möllby, Roland; Kühn, Inger


    We analyzed the prevalence of diarrheagenic Escherichia coli (DEC) markers and common phenotypes in 2,164 E. coli isolates from 282 DEC-positive samples. Enteropathogenic E. coli (EPEC) and enteroaggregative E. coli (EAEC) were very diverse and were not correlated with diarrhea. Enterotoxigenic E. coli (ETEC) estA and enterohemorrhagic E. coli (EHEC) belonged to a few phenotypes and were significantly correlated with diarrhea.

  18. Partners in Earth System Science: a Field, Laboratory and Classroom Based Professional Development Program for K-12 Teachers Designed to Build Scientific and Pedagogical Understandings of Teaching Climate Change. (United States)

    Slattery, W.; Lunsford, S.; Diedrick, A.; Crane, C.


    The purpose of the Partners in Earth System Science summer and academic year professional development program for Ohio K-12 teachers is to build their understandings of the scientific observations, methods and resources that scientists use when studying past and present climate change. Participants then use these tools to develop inquiry-based activities to teach their K-12 students how the scientific method and data are used to understand the effects of global climate change. The summer portion of the program takes teachers from throughout Ohio to the Duke University Marine Laboratory in Beaufort, North Carolina. There they engage in a physical and biological exploration of the modern and ancient ocean. For example, they collect samples of sediment and test water samples collected from modern coastal environments and connect their findings with evidence of the fauna living in those environments. Then, using observations from the geological record of the Eocene through Pleistocene sediments exposed in eastern North Carolina and inferences from observations made from the modern ocean they seek to answer scientifically testable questions regarding the physical and biological characteristics of the ocean during Cenozoic climate change events. During the academic year participants connect with each other and project faculty online to support the development of inquiry based science activities for their K-12 students. These activities focus on how evidence and observations such as outcrop extent, sediment type and biological assemblages can be used to infer past climates. The activities are taught in participant's classrooms and discussed with other participants in an online discussion space. Assessment of both teachers and K-12 students document significant positive changes in science knowledge, their confidence in being able to do science and a clearer understanding of how oceans are impacted by global climate change.

  19. A Library approach to establish an Educational Data Curation Framework (EDCF) that supports K-12 data science sustainability (United States)

    Branch, B. D.; Wegner, K.; Smith, S.; Schulze, D. G.; Merwade, V.; Jung, J.; Bessenbacher, A.


    It has been the tradition of the libraries to support literacy. Now in the realm of Executive Order, Making Open and Machine Readable the New Default for Government Information, May 9, 2013, the library has the responsibility to support geospatial data, big data, earth science data or cyber infrastructure data that may support STEM for educational pipeline stimulation. (Such information can be found at Provided is an Educational Data Curation Framework (EDCF) that has been initiated in Purdue research, geospatial data service engagement and outreach endeavors for future consideration and application to augment such data science and climate literacy needs of future global citizens. In addition, this endorsement of this framework by the GLOBE program may facilitate further EDCF implementations, discussion points and prototypes for libraries. In addition, the ECDF will support teacher-led, placed-based and large scale climate or earth science learning systems where such knowledge transfer of climate or earth science data is effectively transferred from higher education research of cyberinfrastructure use such as, NOAA or NASA, to K-12 teachers and school systems. The purpose of this effort is to establish best practices for sustainable K-12 data science delivery system or GLOBE-provided system ( where libraries manage the data curation and data appropriateness as data reference experts for such digital data. Here, the Purdue University Libraries' GIS department works to support soils, LIDAR and water science data experiences to support teacher training for an EDCF development effort. Lastly, it should be noted that the interdisciplinary collaboration and demonstration of library supported outreach partners and national organizations such the GLOBE program may best foster EDCF development. This trend in data

  20. Teacher Directed Design: Content Knowledge, Pedagogy and Assessment under the Nevada K-12 Real-Time Seismic Network (United States)

    Cantrell, P.; Ewing-Taylor, J.; Crippen, K. J.; Smith, K. D.; Snelson, C. M.


    Education professionals and seismologists under the emerging SUN (Shaking Up Nevada) program are leveraging the existing infrastructure of the real-time Nevada K-12 Seismic Network to provide a unique inquiry based science experience for teachers. The concept and effort are driven by teacher needs and emphasize rigorous content knowledge acquisition coupled with the translation of that knowledge into an integrated seismology based earth sciences curriculum development process. We are developing a pedagogical framework, graduate level coursework, and materials to initiate the SUN model for teacher professional development in an effort to integrate the research benefits of real-time seismic data with science education needs in Nevada. A component of SUN is to evaluate teacher acquisition of qualified seismological and earth science information and pedagogy both in workshops and in the classroom and to assess the impact on student achievement. SUN's mission is to positively impact earth science education practices. With the upcoming EarthScope initiative, the program is timely and will incorporate EarthScope real-time seismic data (USArray) and educational materials in graduate course materials and teacher development programs. A number of schools in Nevada are contributing real-time data from both inexpensive and high-quality seismographs that are integrated with Nevada regional seismic network operations as well as the IRIS DMC. A powerful and unique component of the Nevada technology model is that schools can receive "stable" continuous live data feeds from 100's seismograph stations in Nevada, California and world (including live data from Earthworm systems and the IRIS DMC BUD - Buffer of Uniform Data). Students and teachers see their own networked seismograph station within a global context, as participants in regional and global monitoring. The robust real-time Internet communications protocols invoked in the Nevada network provide for local data acquisition

  1. Creating User-Friendly Tools for Data Analysis and Visualization in K-12 Classrooms: A Fortran Dinosaur Meets Generation Y (United States)

    Chambers, L. H.; Chaudhury, S.; Page, M. T.; Lankey, A. J.; Doughty, J.; Kern, Steven; Rogerson, Tina M.


    During the summer of 2007, as part of the second year of a NASA-funded project in partnership with Christopher Newport University called SPHERE (Students as Professionals Helping Educators Research the Earth), a group of undergraduate students spent 8 weeks in a research internship at or near NASA Langley Research Center. Three students from this group formed the Clouds group along with a NASA mentor (Chambers), and the brief addition of a local high school student fulfilling a mentorship requirement. The Clouds group was given the task of exploring and analyzing ground-based cloud observations obtained by K-12 students as part of the Students' Cloud Observations On-Line (S'COOL) Project, and the corresponding satellite data. This project began in 1997. The primary analysis tools developed for it were in FORTRAN, a computer language none of the students were familiar with. While they persevered through computer challenges and picky syntax, it eventually became obvious that this was not the most fruitful approach for a project aimed at motivating K-12 students to do their own data analysis. Thus, about halfway through the summer the group shifted its focus to more modern data analysis and visualization tools, namely spreadsheets and Google(tm) Earth. The result of their efforts, so far, is two different Excel spreadsheets and a Google(tm) Earth file. The spreadsheets are set up to allow participating classrooms to paste in a particular dataset of interest, using the standard S'COOL format, and easily perform a variety of analyses and comparisons of the ground cloud observation reports and their correspondence with the satellite data. This includes summarizing cloud occurrence and cloud cover statistics, and comparing cloud cover measurements from the two points of view. A visual classification tool is also provided to compare the cloud levels reported from the two viewpoints. This provides a statistical counterpart to the existing S'COOL data visualization tool

  2. Role of Public Outreach in the University Science Mission: Publishing K-12 Curriculum, Organizing Tours, and Other Methods of Engagement (United States)

    Dittrich, T. M.


    Much attention has been devoted in recent years to the importance of Science, Technology, Engineering, and Math (STEM) education in K-12 curriculum for developing a capable workforce. Equally important is the role of the voting public in understanding STEM-related issues that impact public policy debates such as the potential impacts of climate change, hydraulic fracturing in oil and gas exploration, mining impacts on water quality, and science funding. Since voted officials have a major impact on the future of these policies, it is imperative that the general public have an understanding of the basic science behind these issues. By engaging with the public in a more fundamental way, university students can play an important role in educating the public while at the same time enhancing their communication skills and gaining valuable teaching experience. I will talk about my own experiences in (1) evaluating and publishing water chemistry and hazardous waste cleanup curriculum on the K-12 engineering platform, (2) organizing public tours of water and energy sites (e.g., abandoned mine sites, coal power plants, wastewater treatment plants, hazardous waste treatment facilities), and (3) other outreach and communication activities including public education of environmental issues through consultations with customers of a landscaping/lawn mowing company. The main focus of this presentation will be the role that graduate students can play in engaging and educating their local community and lessons learned from community projects (Dittrich, 2014; 2012; 2011). References: Dittrich, T.M. 2014. Adventures in STEM: Lessons in water chemistry from elementary school to graduate school. Abstract ED13E-07 presented at 2014 Fall Meeting, AGU, San Francisco, Calif., 15-19 Dec. Dittrich, T.M. 2012. Collaboration between environmental water chemistry students and hazardous waste treatment specialists on the University of Colorado-Boulder campus. Abstract ED53C

  3. Forest Watch: A K-12 Outreach Program to Engage Pre-College Students in Authentic, Hands-On Science (United States)

    Gagnon, M. T.; Rock, B. N.


    The Forest Watch Program is a K-12 hands-on science outreach program developed at the University of New Hampshire (UNH) in 1991. The program has engaged students and their teachers in assisting researchers at UNH in the assessment of the state-of-health of white pine (Pinus strobus), a known bio-indicator species for exposure to elevated levels of ground-level ozone. Students are introduced to the scientific method while participating in an authentic on-going research program. The program was designed in partnership with participating teachers, and thus the field and classroom activities meet specific New England state science and mathematics curricula standards for K-12 education. Student participation in Forest Watch has resulted in an improved understanding and characterization of inter-annual white pine response to changes in air quality across the region over the past two decades. Forest Watch, students participate in three types of activities: 1. the analysis of remote sensing data (Landsat TM) provided for their local area using MultiSpec freeware. Through image processing, students learn the concepts of spatial and spectral resolution; how to identify landcover features; how plants interact with visible and infrared energy; and how to use this information to determine vegetation types and identify vegetation conditions. 2. students select 5 white pine trees to be permanently tagged near their school within a 30x30 meter (pixel sized sampling plot - the spatial resolution of the TM dataset), followed by collection and analysis of needle samples, and a suite of forest plot biometric measurements such as tree height, diameter at breast height (DBH), and canopy closure and ground cover. 3. the students send a set of their needle samples to UNH for spectral analysis of key reflectance features such as the Red Edge Inflection Point (REIP), the TM 5/4 moisture stress index, and the NIR 3/1. Over 250 schools from all six New England states have participated in the

  4. The Activity of [60]Fullerene Derivatives Bearing Amine and Carboxylic Solubilizing Groups against Escherichia coli: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Dmitry G. Deryabin


    Full Text Available We report a comparative investigation of the antibacterial activity of two water-soluble fullerene derivatives bearing protonated amine (AF and deprotonated carboxylic (CF groups appended to the fullerene cage via organic linkers. The negatively charged fullerene derivative CF showed no tendency to bind to the bacterial cells and, consequently, no significant antibacterial activity. In contrast, the compound AF loaded with cationic groups showed strong and partially irreversible binding to the negatively charged Escherichia coli K12 TG1 cells and to human erythrocytes, also possessing negative zeta potential. Adsorption of AF on the bacterial surface was visualized by atomic force microscopy revealing the formation of specific clusters (AF aggregates surrounding the bacterial cell. Incubation of E. coli K12 TG1 with AF led to a dose-dependent bactericidal effect with LD50 = 79.1 µM. The presence of human erythrocytes in the test medium decreased the AF antibacterial activity. Thus we reveal that the water-soluble cationic fullerene derivative AF possesses promising antibacterial activity, which might be utilized in the development of novel types of chemical disinfectants.

  5. Defining the requisite knowledge for providers of in-service professional development for K--12 teachers of science: Refining the construct (United States)

    Tucker, Deborah L.

    Purpose. The purpose of this grounded theory study was to refine, using a Delphi study process, the four categories of the theoretical model of the comprehensive knowledge base required by providers of professional development for K-12 teachers of science generated from a review of the literature. Methodology. This grounded theory study used data collected through a modified Delphi technique and interviews to refine and validate the literature-based knowledge base required by providers of professional development for K-12 teachers of science. Twenty-three participants, experts in the fields of science education, how people learn, instructional and assessment strategies, and learning contexts, responded to the study's questions. Findings. By "densifying" the four categories of the knowledge base, this study determined the causal conditions (the science subject matter knowledge), the intervening conditions (how people learn), the strategies (the effective instructional and assessment strategies), and the context (the context and culture of formal learning environments) surrounding the science professional development process. Eight sections were added to the literature-based knowledge base; the final model comprised of forty-nine sections. The average length of the operational definitions increased nearly threefold and the number of citations per operational definition increased more than twofold. Conclusions. A four-category comprehensive model that can serve as the foundation for the knowledge base required by science professional developers now exists. Subject matter knowledge includes science concepts, inquiry, the nature of science, and scientific habits of mind; how people learn includes the principles of learning, active learning, andragogy, variations in learners, neuroscience and cognitive science, and change theory; effective instructional and assessment strategies include constructivist learning and inquiry-based teaching, differentiation of instruction

  6. ESBL-Producing Escherichia coli

    DEFF Research Database (Denmark)

    Hertz, Frederik Boetius

    Urinary tract infection (UTI) is one the most common bacterial infections and is regularly treated in primary health care. The most common cause of UTI is extraintestinal pathogenic Escherichia coli (ExPEC) already present in the intestinal microflora, often as the dominating strain. Resistance...... in E.coli is increasing and especially isolates producing Extended-Spectrum Beta-Lactamases (ESBL) have been reported worldwide. Treatment of UTI is usually initiated by the general practitioners and a significant proportion of clinical isolates are now resistant to first line antibiotics. The global...... dissemination of resistant E.coli has in particular been driven by the spread of a few specific E.coli-lineages and it seems that there is a difference between the sequence types found among resistant E.coli, ESBL-producing E.coli and antibiotic susceptible E.coli. The overall objectives of this thesis were...

  7. Secrets of the Sediments: Using ANDRILL's Scientific Adventure on Ice to Transfer Climate Change Science to K-12 Audiences (United States)

    Huffman, L. T.; Dahlman, L.; Frisch-Gleason, R.; Harwood, D.; Pound, K.; Rack, F.; Riesselman, C.; Trummel, E.; Tuzzi, E.; Winter, D.


    Antarctica's harsh environment and the compelling story of living and working there, provides the backdrop for hooking the interest of young learners on science research and the nature of science. By using the adventure stories of today's researcher-explorers, teachers accompanying the ANDRILL team have taken the technical science of drilling rock cores to understand the history of climate change and the advance and retreat of the Antarctic ice sheet, and translated it for non-technical audiences from K-12 school children, to adult community groups. In order to understand the important issues surrounding global climate change, members of the public need access to accurate and relevant information, high quality educational materials, and a variety of learning opportunities in different learning environments. By taking lessons learned from early virtual polar adventure learning expeditions like Will Steger's Trans-Antarctic Expedition, coupled with educators-in-the-field programs like TEA (Teachers Experiencing Antarctica and the Arctic), ARMADA and Polar Trec, ANDRILL's Education and Outreach Program has evolved into successful and far-reaching integrated education projects including 1) the ARISE (ANDRILL Research Immersion for Science Educators) Program, 2) Climate Change Student Summits, 3) the development of Flexhibit (flexible exhibit) teaching resources, 4) virtual online learning communities, and 5) partnering young researchers with teachers and classrooms. Formal evaluations indicate lasting interest in science studies on the part of students and an increase in teachers' scientific background knowledge.

  8. Open Educational Resources from Performance Task using Video Analysis and Modeling - Tracker and K12 science education framework

    CERN Document Server

    Wee, Loo Kang


    This invited paper discusses why Physics performance task by grade 9 students in Singapore is worth participating in for two reasons; 1) the video analysis and modeling are open access, licensed creative commons attribution for advancing open educational resources in the world and 2) allows students to be like physicists, where the K12 science education framework is adopted. Personal reflections on how physics education can be made more meaningful in particular Practice 1: Ask Questions, Practice 2: Use Models and Practice 5: Mathematical and Computational Thinking using Video Modeling supported by evidence based data from video analysis. This paper hopes to spur fellow colleagues to look into open education initiatives such as our Singapore Tracker community open educational resources curate on as well as digital libraries directly accessible through Tracker 4.86, EJSS reader app on Android and iOS and EJS 5....

  9. Cascadia Initiative Broader Impacts to Influence Student Career Choices and Engage K-12 Schools in Seismic Hazard Preparedness (United States)

    Livelybrooks, D.; Richter, M.; Head, E.; Toomey, D. R.; Trehu, A. M.; Tolstoy, M.


    The Cascadia Initiative is an amphibious seismic and geodetic experiment addressing questions about volcanic arc structure to formation, hydration and deformation of the Juan de Fuca and Gorda plates to megathrust earthquake genesis, interface characterization and forearc prism phenomenon. Broader impacts for the Cascadia Initiative include a program placing community college students onboard cruises and following up with presentations and other outreach on community college campuses and elsewhere ('CC@sea'). The first two CC@sea-ers participated in the first cruise to deploy ocean-bottom seismometers off the Washington and Oregon coast in July, 2011 and returned to their home campuses in Portland and rural Oregon fall term. A goal of CC@sea is to increase participation by community college students, typically from diverse backgrounds, in geoscience career paths, either through direct participation in CC@sea or through indirect exposure to CC@sea-ers. Another outreach program (seismometers@school) will place seismometers in Pacific NW schools for long-term monitoring of ground motion at different buildings within a school district. High school teachers and students will help analyze their data to characterize local shaking at individual schools within their districts. This will supplement other assessments of seismic risk and culminate in presentations to school boards where students and teachers can advocate for improved K-12 preparedness for potentially devastating Cascadia megathrust events. A teacher workshop to kick-start seismometers@school takes place November, 2011.

  10. Divergent responses to peptidoglycans derived from different E. coli serotypes influence inflammatory outcome in trout, Oncorhynchus mykiss, macrophages

    Directory of Open Access Journals (Sweden)

    Goetz Frederick


    Full Text Available Abstract Background Pathogen-associated molecular patterns (PAMPs are structural components of pathogens such as lipopolysaccharide (LPS and peptidoglycan (PGN from bacterial cell walls. PAMP-recognition by the host results in an induction of defence-related genes and often the generation of an inflammatory response. We evaluated both the transcriptomic and inflammatory response in trout (O. mykiss macrophages in primary cell culture stimulated with DAP-PGN (DAP; meso-diaminopimelic acid, PGN; peptidoglycan from two strains of Escherichia coli (PGN-K12 and PGN-O111:B4 over time. Results Transcript profiling was assessed using function-targeted cDNA microarray hybridisation (n = 36 and results show differential responses to both PGNs that are both time and treatment dependent. Wild type E. coli (K12 generated an increase in transcript number/diversity over time whereas PGN-O111:B4 stimulation resulted in a more specific and intense response. In line with this, Gene Ontology analysis (GO highlights a specific transcriptomic remodelling for PGN-O111:B4 whereas results obtained for PGN-K12 show a high similarity to a generalised inflammatory priming response where multiple functional classes are related to ribosome biogenesis or cellular metabolism. Prostaglandin release was induced by both PGNs and macrophages were significantly more sensitive to PGN-O111:B4 as suggested from microarray data. Conclusion Responses at the level of the transcriptome and the inflammatory outcome (prostaglandin synthesis highlight the different sensitivity of the macrophage to slight differences (serotype in peptidoglycan structure. Such divergent responses are likely to involve differential receptor sensitivity to ligands or indeed different receptor types. Such changes in biological response will likely reflect upon pathogenicity of certain serotypes and the development of disease.

  11. A systems biology approach identified different regulatory networks targeted by KSHV miR-K12-11 in B cells and endothelial cells. (United States)

    Yang, Yajie; Boss, Isaac W; McIntyre, Lauren M; Renne, Rolf


    Kaposi's sarcoma associated herpes virus (KSHV) is associated with tumors of endothelial and lymphoid origin. During latent infection, KSHV expresses miR-K12-11, an ortholog of the human tumor gene hsa-miR-155. Both gene products are microRNAs (miRNAs), which are important post-transcriptional regulators that contribute to tissue specific gene expression. Advances in target identification technologies and molecular interaction databases have allowed a systems biology approach to unravel the gene regulatory networks (GRNs) triggered by miR-K12-11 in endothelial and lymphoid cells. Understanding the tissue specific function of miR-K12-11 will help to elucidate underlying mechanisms of KSHV pathogenesis. Ectopic expression of miR-K12-11 differentially affected gene expression in BJAB cells of lymphoid origin and TIVE cells of endothelial origin. Direct miRNA targeting accounted for a small fraction of the observed transcriptome changes: only 29 genes were identified as putative direct targets of miR-K12-11 in both cell types. However, a number of commonly affected biological pathways, such as carbohydrate metabolism and interferon response related signaling, were revealed by gene ontology analysis. Integration of transcriptome profiling, bioinformatic algorithms, and databases of protein-protein interactome from the ENCODE project identified different nodes of GRNs utilized by miR-K12-11 in a tissue-specific fashion. These effector genes, including cancer associated transcription factors and signaling proteins, amplified the regulatory potential of a single miRNA, from a small set of putative direct targets to a larger set of genes. This is the first comparative analysis of miRNA-K12-11's effects in endothelial and B cells, from tissues infected with KSHV in vivo. MiR-K12-11 was able to broadly modulate gene expression in both cell types. Using a systems biology approach, we inferred that miR-K12-11 establishes its GRN by both repressing master TFs and influencing

  12. Effects of Outer Membrane Protein TolC on the Transport of Escherichia coli within Saturated Quartz Sands (United States)

    Feriancikova, Lucia; Bardy, Sonia L.; Wang, Lixia; Li, Jin; Xu, Shangping


    The outer membrane protein (OMP) TolC is the cell surface component of several drug efflux pumps that are responsible for bacterial resistance against a variety of antibiotics. In this research, we investigated the effects of OMP TolC on E. coli transport within saturated sands through column experiments using a wide type E. coli K12 strain (with OMP TolC), as well as the corresponding transposon mutant (tolC∷kan) and the markerless deletion mutant (ΔtolC). Our results showed OMP TolC could significantly enhance the transport of E. coli when the ionic strength was 20 mM NaCl or higher. The deposition rate coefficients for the wild type E. coli strain (with OMP TolC) was usually >50% lower than those of the tolC-negative mutants. The measurements of contact angles using three probe liquids suggested that TolC altered the surface tension components of E. coli cells and lead to lower Hamaker constants for the cell-water-sand system. The interaction energy calculations using the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory suggested that the deposition of the E. coli cell primarily occurred at the secondary energy minimum. The depth of the secondary energy minimum increased with ionic strength, and was greater for the TolC-deletion strains under high ionic strength conditions. Overall, the transport behavior of three E. coli strain within saturated sands could be explained by the XDLVO calculations. Results from this research suggested that antibiotic resistant bacteria expressing OMP TolC could spread more widely within sandy aquifers. PMID:23627691

  13. Effects of outer membrane protein TolC on the transport of Escherichia coli within saturated quartz sands. (United States)

    Feriancikova, Lucia; Bardy, Sonia L; Wang, Lixia; Li, Jin; Xu, Shangping


    The outer membrane protein (OMP) TolC is the cell surface component of several drug efflux pumps that are responsible for bacterial resistance against a variety of antibiotics. In this research, we investigated the effects of OMP TolC on E. coli transport within saturated sands through column experiments using a wild-type E. coli K12 strain (with OMP TolC), as well as the corresponding transposon mutant (tolC::kan) and the markerless deletion mutant (ΔtolC). Our results showed OMP TolC could significantly enhance the transport of E. coli when the ionic strength was 20 mM NaCl or higher. The deposition rate coefficients for the wild-type E. coli strain (with OMP TolC) was usually >50% lower than those of the tolC-negative mutants. The measurements of contact angles using three probe liquids suggested that TolC altered the surface tension components of E. coli cells and lead to lower Hamaker constants for the cell-water-sand system. The interaction energy calculations using the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory suggested that the deposition of the E. coli cell primarily occurred at the secondary energy minimum. The depth of the secondary energy minimum increased with ionic strength, and was greater for the TolC-deletion strains under high ionic strength conditions. Overall, the transport behavior of three E. coli strains within saturated sands could be explained by the XDLVO calculations. Results from this research suggested that antibiotic resistant bacteria expressing OMP TolC could spread more widely within sandy aquifers.

  14. Global analysis of translation termination in E. coli. (United States)

    Baggett, Natalie E; Zhang, Yan; Gross, Carol A


    Terminating protein translation accurately and efficiently is critical for both protein fidelity and ribosome recycling for continued translation. The three bacterial release factors (RFs) play key roles: RF1 and 2 recognize stop codons and terminate translation; and RF3 promotes disassociation of bound release factors. Probing release factors mutations with reporter constructs containing programmed frameshifting sequences or premature stop codons had revealed a propensity for readthrough or frameshifting at these specific sites, but their effects on translation genome-wide have not been examined. We performed ribosome profiling on a set of isogenic strains with well-characterized release factor mutations to determine how they alter translation globally. Consistent with their known defects, strains with increasingly severe release factor defects exhibit increasingly severe accumulation of ribosomes over stop codons, indicative of an increased duration of the termination/release phase of translation. Release factor mutant strains also exhibit increased occupancy in the region following the stop codon at a significant number of genes. Our global analysis revealed that, as expected, translation termination is generally efficient and accurate, but that at a significant number of genes (≥ 50) the ribosome signature after the stop codon is suggestive of translation past the stop codon. Even native E. coli K-12 exhibits the ribosome signature suggestive of protein extension, especially at UGA codons, which rely exclusively on the reduced function RF2 variant of the K-12 strain for termination. Deletion of RF3 increases the severity of the defect. We unambiguously demonstrate readthrough and frameshifting protein extensions and their further accumulation in mutant strains for a few select cases. In addition to enhancing recoding, ribosome accumulation over stop codons disrupts attenuation control of biosynthetic operons, and may alter expression of some overlapping genes

  15. Developing Young Researchers: 15 Years of Authentic Science Experiences for K-12 with NASA's S'COOL Project (United States)

    Chambers, L. H.; Crecelius, S.; Rogerson, T.; Lewis, P. M.; Moore, S.; Madigan, J. J.; Deller, C.; Taylor, J.


    In late 1996, members of the Atmospheric Science Directorate at NASA's Langley Research Center decided that there had to be a better way to share the excitement of our research than black and white, text-heavy Fact Sheets. We invited a group of local teachers to a half-day session on Center to help guide an improved approach. We suggested a variety of approaches to them, and asked for feedback. They were eager for anything other than black and white Fact Sheets! Fortunately, one local middle school science teacher took us up on the offer to stick around and talk over lunch. In that conversation, she said that anything that would connect the science her kids studied in the classroom to the outside world - especially to NASA! - would be very motivating to her students. From that conversation was born the Students' Cloud Observations On-Line (S'COOL Project), now a nearly 16-year experiment in K-12 science, technology, engineering, and math (STEM) engagement. S'COOL is the Education and Public Outreach (EPO) arm of the Clouds and the Earth's Radiant Energy System (CERES) project, and involves K-12 students as a source of ground truth for satellite cloud retrievals. It was designed from the beginning as a 2-way project, with communication of information from the students to NASA, but also from NASA back to the students. With technology evolution since the project began, we have continued to enhance this focus on 2-way interaction. S'COOL involves students with observation skills, math skills (to compute cloud cover from multiple observers or convert units), geography skills (locating their school on a map and comparing to satellite imagery), and exposes them to cutting edge engineering in the form of a series of NASA satellites. As a priority Earth Observing Instrument, CERES currently flies on Terra, Aqua and NPP, with an additional instrument in development for JPSS. Students are involved in occasional Intensive Observing Periods (as with the launch of NPP), and are

  16. The GLOBE Carbon Project: Integrating the Science of Carbon Cycling and Climate Change into K-12 Classrooms. (United States)

    Ollinger, S. V.; Silverberg, S.; Albrechtova, J.; Freuder, R.; Gengarelly, L.; Martin, M.; Randolph, G.; Schloss, A.


    The global carbon cycle is a key regulator of the Earth's climate and is central to the normal function of ecological systems. Because rising atmospheric CO2 is the principal cause of climate change, understanding how ecosystems cycle and store carbon has become an extremely important issue. In recent years, the growing importance of the carbon cycle has brought it to the forefront of both science and environmental policy. The need for better scientific understanding has led to establishment of numerous research programs, such as the North American Carbon Program (NACP), which seeks to understand controls on carbon cycling under present and future conditions. Parallel efforts are greatly needed to integrate state-of-the-art science on the carbon cycle and its importance to climate with education and outreach efforts that help prepare society to make sound decisions on energy use, carbon management and climate change adaptation. Here, we present a new effort that joins carbon cycle scientists with the International GLOBE Education program to develop carbon cycle activities for K-12 classrooms. The GLOBE Carbon Cycle project is focused on bringing cutting edge research and research techniques in the field of terrestrial ecosystem carbon cycling into the classroom. Students will collect data about their school field site through existing protocols of phenology, land cover and soils as well as new protocols focused on leaf traits, and ecosystem growth and change. They will also participate in classroom activities to understand carbon cycling in terrestrial ecosystems, these will include plant- a-plant experiments, hands-on demonstrations of various concepts, and analysis of collected data. In addition to the traditional GLOBE experience, students will have the opportunity to integrate their data with emerging and expanding technologies including global and local carbon cycle models and remote sensing toolkits. This program design will allow students to explore research

  17. Teachers on the Leading Edge: A Place-Based Professional Development Program for K-12 Earth Science Teachers (United States)

    Butler, Robert


    Teachers on the Leading Edge (TOTLE) is an Earth Science teacher professional development program featuring Pacific Northwest active continental margin geology. To engage middle-school teachers and students, TOTLE workshops: (1) invite novice learners to geophysical studies of tectonics, earthquakes, and volcanoes; (2) provide access to EarthScope research; and (3) explain geologic hazards as understandable aspects of living on the ``leading edge'' of the North American continent. Fundamental concepts and observations progress from global patterns, to regional context, and then to local applications. For example, earthquakes are concentrated near tectonic plate boundaries such as the Cascadia subduction zone between the Juan de Fuca and North American plates. Earthquake hazards include liquefaction and landslides that are affected by regional and local geology. And relative earthquake hazard maps provide comparisons of hazards on county, city, and neighborhood scales. Inquiry-based field investigation of coastal ghost forests and Cascadia tsunami geology stimulates learning about Cascadia great earthquakes and tsunamis and provides a case study of scientific discovery. Field studies of volcanic mudflow (lahar) deposits from Mt Hood and Mt Rainier highlight volcanic hazards to rapidly increasing populations that live near recently active Cascade volcanoes. We emphasize the importance of infrastructure engineering and emergency preparedness in preventing geologic hazards damage, injuries, and deaths in order to: (1) demonstrate how Geoscience research leads to improved engineering designs that mitigate hazards; (2) align lessons with national and state K-12 science education standards that focus on science, technology, and societal connections; and (3) avoid fatalism and develop a culture of geologic hazards awareness among future citizens of the Pacific Northwest.

  18. Astrobiobound! Search for Life in the Solar System: Scientists and Engineers Bringing their Challenges to K-12 Students (United States)

    Klug Boonstra, S. L.; Swann, J.; Manfredi, L.; Zippay, A.; Boonstra, D.


    The Next Generation Science Standards (NGSS) brought many dynamic opportunities and capabilities to the K-12 science classroom - especially with the inclusion of engineering. Using science as a context to help students engage in the engineering practices and engineering disciplinary core ideas is an essential step to students' understanding of how science drives engineering and how engineering enables science. Real world examples and applications are critical for students to see how these disciplines are integrated. Furthermore, the interface of science and engineering raise the level of science understanding, and facilitate higher order thinking skills through relevant experiences. Astrobiobound! is designed for the NGSS (Next Generation Science Standards) and CCSS (Common Core State Standards). Students also practice and build 21st Century Skills. Astrobiobound! help students see how science and systems engineering are integrated to achieve a focused scientific goal. Students engage in the engineering design process to design a space mission which requires them to balance the return of their science data with engineering limitations such as power, mass and budget. Risk factors also play a role during this simulation and adds to the excitement and authenticity. Astrobiobound! presents the authentic first stages of NASA mission design process. This simulation mirrors the NASA process in which the science goals, type of mission, and instruments to return required data to meet mission goals are proposed within mission budget before any of the construction part of engineering can begin. NASA scientists and engineers were consulted in the development of this activity as an authentic simulation of their mission proposal process.

  19. Effects of high hydrostatic pressure and temperature increase on Escherichia coli spp. and pectin methyl esterase inactivation in orange juice. (United States)

    Torres, E F; González-M, G; Klotz, B; Rodrigo, D


    The aim of this study was to evaluate the effect of high hydrostatic pressure treatment combined with moderate processing temperatures (25 ℃-50 ℃) on the inactivation of Escherichia coli O157: H7 (ATCC 700728), E. coli K12 (ATCC 23716), and pectin methyl esterase in orange juice, using pressures of 250 to 500 MPa with times ranging between 1 and 30 min. Loss of viability of E. coli O157:H7 increased significantly as pressure and treatment time increased, achieving a 6.5 log cycle reduction at 400 MPa for 3 min at 25 ℃ of treatment. With regard to the inactivation of pectin methyl esterase, the greatest reduction obtained was 90.05 ± 0.01% at 50 ℃ and 500 MPa of pressure for 15 min; therefore, the pectin methyl esterase enzyme was highly resistant to the treatments by high hydrostatic pressure. The results obtained in this study showed a synergistic effect between the high pressure and moderate temperatures in inactivating E. coli cells. © The Author(s) 2016.

  20. Discrimination of Pathogenic Versus Non-Pathogenic Yersinia Pestis and Escherichia Coli Using Proteomics Mass Spectrometry (United States)


    The bacterial classification and identification algorithm used assignments of organisms to taxonomic groups (phylogenetic classification ) based on an... organized scheme that begins at the phylum level and follows through classes, orders, families and genus down to strain level. BACid was developed...neighbor Classification of Pathogenic E. coli 0157:H7 vs. Non-pathogenic E. coli K12 Using Whole Cell Lysates 12 4. Near-neighbor Classification of Non