Sample records for exploring medium effects

  1. A Comparative Study on the Effectiveness of English-Medium and Turkish-Medium Accounting Education: Gazi University Case

    ERIC Educational Resources Information Center

    Zaif, Figen; Karapinar, Aydin; Yangin Eksi, Gonca

    2017-01-01

    The authors explore the effect of medium of instruction on students' attainments at a large state university in Turkey in the Department of Business Administration. The findings indicate no statistically significant difference in grades of 386 students with respect to medium of instruction. As for entry rankings however, those in the…

  2. Metamaterial-based lossy anisotropic epsilon-near-zero medium for energy collimation

    NASA Astrophysics Data System (ADS)

    Shen, Nian-Hai; Zhang, Peng; Koschny, Thomas; Soukoulis, Costas M.

    2016-06-01

    A lossy anisotropic epsilon-near-zero (ENZ) medium may lead to a counterintuitive phenomenon of omnidirectional bending-to-normal refraction [S. Feng, Phys. Rev. Lett. 108, 193904 (2012), 10.1103/PhysRevLett.108.193904], which offers a fabulous strategy for energy collimation and energy harvesting. Here, in the scope of effective medium theory, we systematically investigate two simple metamaterial configurations, i.e., metal-dielectric-layered structures and the wire medium, to explore the possibility of fulfilling the conditions of such an anisotropic lossy ENZ medium by playing with materials' parameters. Both realistic metamaterial structures and their effective medium equivalences have been numerically simulated, and the results are in excellent agreement with each other. Our study provides clear guidance and therefore paves the way towards the search for proper designs of anisotropic metamaterials for a decent effect of energy collimation and wave-front manipulation.

  3. [Induction on callus culture and regeneration of Orostachyis fimbriatae].

    PubMed

    Su, Rui-jun; Zou, Li-juan; Wu, Qing-gui; Luo, Ming-hua

    2014-01-01

    To explore the effects of different hormonal combinations on induction, proliferation and differentiation of Orostachyis fimbriatae callus culture. Aseptic seedling leaves were used as explants,the different concentrations of IAA,NAA, 6-BA and KT on induction proliferation of callus were optimized by orthogonal test to explore the optimum medium for differentiation of callus by tissue culture techniques. The best medium for induction was MS + IAA 1.0 mg/L + NAA 0.5 mg/L + KT 1.0 mg/L, and the best hormonal combination for proliferation was MS + IAA 0.5 mg/L + 6-BA 0.5 mg/I. + KT 1.0 mg/L. The best medium for differentiation was MS + IAA 0.1 mg/L + KT 2.0 mg/L, and 1/2MS + IAA 0.2 mg/L was the optimum medium for rooting culture. The system of regeneration of Orostachyis fimbriatae is establishd by tissue culture techniques in this study.

  4. Hydrogen-Rich Medium Attenuated Lipopolysaccharide-Induced Monocyte-Endothelial Cell Adhesion and Vascular Endothelial Permeability via Rho-Associated Coiled-Coil Protein Kinase.

    PubMed

    Xie, Keliang; Wang, Weina; Chen, Hongguang; Han, Huanzhi; Liu, Daquan; Wang, Guolin; Yu, Yonghao

    2015-07-01

    Sepsis is the leading cause of death in critically ill patients. In recent years, molecular hydrogen, as an effective free radical scavenger, has been shown a selective antioxidant and anti-inflammatory effect, and it is beneficial in the treatment of sepsis. Rho-associated coiled-coil protein kinase (ROCK) participates in junction between normal cells, and regulates vascular endothelial permeability. In this study, we used lipopolysaccharide to stimulate vascular endothelial cells and explored the effects of hydrogen-rich medium on the regulation of adhesion of monocytes to endothelial cells and vascular endothelial permeability. We found that hydrogen-rich medium could inhibit adhesion of monocytes to endothelial cells and decrease levels of adhesion molecules, whereas the levels of transepithelial/endothelial electrical resistance values and the expression of vascular endothelial cadherin were increased after hydrogen-rich medium treatment. Moreover, hydrogen-rich medium could lessen the expression of ROCK, as a similar effect of its inhibitor Y-27632. In addition, hydrogen-rich medium could also inhibit adhesion of polymorphonuclear neutrophils to endothelial cells. In conclusion, hydrogen-rich medium could regulate adhesion of monocytes/polymorphonuclear neutrophils to endothelial cells and vascular endothelial permeability, and this effect might be related to the decreased expression of ROCK protein.

  5. Are Science Comics a Good Medium for Science Communication? The Case for Public Learning of Nanotechnology

    ERIC Educational Resources Information Center

    Lin, Shu-Fen; Lin, Huann-shyang; Lee, Ling; Yore, Larry D.

    2015-01-01

    Comic books possessing the features of humour, narrative, and visual representation are deemed as a potential medium for science communication; however, empirical studies exploring the effects of comics are scarce. The purposes of this study were to examine and compare the impacts of a comic book and a text booklet on conveying the concepts of…

  6. An Exploration of the Effects of Language Policy in Education in a Contemporary Puerto Rican Society

    ERIC Educational Resources Information Center

    Maldonado-Valentín, Mirta

    2016-01-01

    During the Spanish regimen, Puerto Rican education was limited and restricted to Spanish language as the medium of instruction. It was not until the U.S. colonization of the island that public education was introduced. As a result, English replaced Spanish as medium of instruction in the new educational system. Immediately after, Puerto Rican…

  7. English as a Medium of Instruction in the Gulf: When Students and Teachers Speak

    ERIC Educational Resources Information Center

    Belhiah, Hassan; Elhami, Maha

    2015-01-01

    This study explores the effectiveness of English as a medium of instruction (EMI) in the Arabian/Persian Gulf, with special focus on the situation in the United Arab Emirates. The study, undertaken at six universities located in major cities of Abu Dhabi, Dubai, Al Ain, Sharjah, Ajman, and Ras Al Khaimah, examines students' and teachers'…

  8. A Correlational Study between IT Governance and the Effect on Strategic Management Functioning among Senior & Middle Management in Medium Scale Software Organizations

    ERIC Educational Resources Information Center

    Kurien, Sam

    2013-01-01

    The purpose of the study was to explore whether there are relationships between elements of information technology (IT) governance, strategic planning, and strategic functions among senior and mid-level management at medium-scaled software development firms. Several topics and models of IT governance literature were discussed and the gap in…

  9. Learning to Design WebQuests: An Exploration in Preservice Social Studies Education

    ERIC Educational Resources Information Center

    Bates, Alisa

    2008-01-01

    Effective uses of technology in social studies methods courses is an under-researched field. This study focused on the development of WebQuests to engage teacher candidate's exploration of the Internet as an authentic medium for inquiry in social studies education. Analysis of appropriateness of tasks in the WebQuests, depth of ideas and audience…

  10. Double-Zero-Index Structural Phononic Waveguides

    NASA Astrophysics Data System (ADS)

    Zhu, Hongfei; Semperlotti, Fabio

    2017-12-01

    We report on the theoretical and experimental realization of a double-zero-index elastic waveguide and the corresponding acoustic cloaking and supercoupling effects. The proposed waveguide uses geometric tapers in order to induce Dirac-like cones at k → =0 due to accidental degeneracy. The nature of the degeneracy is explored by a k .p perturbation method adapted to thin structural waveguides. The results confirm the linear nature of the dispersion around the degeneracy and the possibility to map the material to effective-medium properties. Effective parameters numerically extracted using boundary medium theory confirm that the phononic waveguide maps into a double-zero-index material. Numerical and experimental results confirm the expected cloaking and supercoupling effects.

  11. Turkish University Students' Perceptions about English Medium Instruction: Exploring Year Group, Gender and University Type as Variables

    ERIC Educational Resources Information Center

    Macaro, Ernesto; Akincioglu, Mustafa

    2018-01-01

    In Turkey, as in much of the rest of the non-Anglophone world, universities are offering an increasing number of courses through English Medium Instruction (EMI) rather than through the medium of the first language (L1) of the majority of the population. Previous research has explored teacher and student perceptions and attitudes towards EMI and…

  12. What impact do posters have on academic knowledge transfer? A pilot survey on author attitudes and experiences.

    PubMed

    Rowe, Nicholas; Ilic, Dragan

    2009-12-08

    Research knowledge is commonly facilitated at conferences via oral presentations, poster presentations and workshops. Current literature exploring the efficacy of academic posters is however limited. The purpose of this initial study was to explore the perceptions of academic poster presentation, together with its benefits and limitations as an effective mechanism for academic knowledge transfer and contribute to the available academic data. A survey was distributed to 88 delegates who presented academic posters at two Releasing Research and Enterprise Potential conferences in June 2007 and June 2008 at Bournemouth University. This survey addressed attitude and opinion items, together with their general experiences of poster presentations. Descriptive statistics were performed on the responses. A 39% return was achieved with the majority of respondents believing that posters are a good medium for transferring knowledge and a valid form of academic publication. Visual appeal was cited as more influential than subject content, with 94% agreeing that poster imagery is most likely to draw viewer's attention. Respondents also believed that posters must be accompanied by their author in order to effectively communicate the academic content. This pilot study is the first to explore perceptions of the academic poster as a medium for knowledge transfer. Given that academic posters rely heavily on visual appeal and direct author interaction, the medium requires greater flexibility in their design to promote effective knowledge transfer. This paper introduces the concept of the IT-based 'MediaPoster' so as to address the issues raised within published literature and subsequently enhance knowledge-transfer within the field of academic medicine.

  13. Which Is the Optimal Biologically Effective Dose of Stereotactic Body Radiotherapy for Stage I Non-Small-Cell Lung Cancer? A Meta-Analysis

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

    Zhang Jian; Yang Fujun; Department of Radiation Oncology, Shandong Cancer Hospital, Shandong Academy of Medical Sciences, Jinan

    2011-11-15

    Purpose: To assess the relationship between biologically effective dose (BED) and efficacy of stereotactic body radiation therapy (SBRT) and to explore the optimal BED range for Stage I non-small-cell lung cancer (NSCLC). Methods and Materials: Eligible studies were identified on Medline, Embase, the Cochrane Library, and the proceedings of annual meetings through June 2010. According to the quartile of included studies, BED was divided into four dose groups: low (<83.2 Gy), medium (83.2-106 Gy), medium to high (106-146 Gy), high (>146 Gy). To obtain pooled estimates of overall survival (OS), cancer-specific survival (CSS), and local control rate (LCR), data weremore » combined in a random effect model. Pooled estimates were corrected for the percentage of small tumors (<3 cm). Results: Thirty-four observational studies with a total of 2,587 patients were included in the meta-analysis. Corrected pooled estimates of 2- or 3-year OS in the medium BED (76.1%, 63.5%) or the medium to high BED (68.3%, 63.2%) groups were higher than in the low (62.3%, 51.9%) or high groups (55.9%, 49.5%), respectively (p {<=} 0.004). Corrected 3-year CSS in the medium (79.5%), medium to high (80.6%), and high groups (90.0%) were higher than in the low group (70.1%, p = 0.016, 0.018, 0.001, respectively). Conclusion: The OS for the medium or medium to high BED groups were higher than those for the low or high BED group for SBRT in Stage I NSCLC. The medium or medium to high BED (range, 83.2-146 Gy) for SBRT may currently be more beneficial and reasonable in Stage I NSCLC.« less

  14. Estimation of Random Medium Parameters from 2D Post-Stack Seismic Data and Its Application in Seismic Inversion

    NASA Astrophysics Data System (ADS)

    Yang, X.; Zhu, P.; Gu, Y.; Xu, Z.

    2015-12-01

    Small scale heterogeneities of subsurface medium can be characterized conveniently and effectively using a few simple random medium parameters (RMP), such as autocorrelation length, angle and roughness factor, etc. The estimation of these parameters is significant in both oil reservoir prediction and metallic mine exploration. Poor accuracy and low stability existed in current estimation approaches limit the application of random medium theory in seismic exploration. This study focuses on improving the accuracy and stability of RMP estimation from post-stacked seismic data and its application in the seismic inversion. Experiment and theory analysis indicate that, although the autocorrelation of random medium is related to those of corresponding post-stacked seismic data, the relationship is obviously affected by the seismic dominant frequency, the autocorrelation length, roughness factor and so on. Also the error of calculation of autocorrelation in the case of finite and discrete model decreases the accuracy. In order to improve the precision of estimation of RMP, we design two improved approaches. Firstly, we apply region growing algorithm, which often used in image processing, to reduce the influence of noise in the autocorrelation calculated by the power spectrum method. Secondly, the orientation of autocorrelation is used as a new constraint in the estimation algorithm. The numerical experiments proved that it is feasible. In addition, in post-stack seismic inversion of random medium, the estimated RMP may be used to constrain inverse procedure and to construct the initial model. The experiment results indicate that taking inversed model as random medium and using relatively accurate estimated RMP to construct initial model can get better inversion result, which contained more details conformed to the actual underground medium.

  15. Realization of a complementary medium using dielectric photonic crystals.

    PubMed

    Xu, Tao; Fang, Anan; Jia, Ziyuan; Ji, Liyu; Hang, Zhi Hong

    2017-12-01

    By exploiting the scaling invariance of photonic band diagrams, a complementary photonic crystal slab structure is realized by stacking two uniformly scaled double-zero-index dielectric photonic crystal slabs together. The space cancellation effect in complementary photonic crystals is demonstrated in both numerical simulations and microwave experiments. The refractive index dispersion of double-zero-index dielectric photonic crystal is experimentally measured. Using pure dielectrics, our photonic crystal structure will be an ideal platform to explore various intriguing properties related to a complementary medium.

  16. Research on Cognitive Effects of Non-Educational TV: An Epistemological Discussion.

    ERIC Educational Resources Information Center

    Gomez, Guillermo Orozco

    This paper makes a critical exploration into the core epistemological assumptions of mainstream television effects research and explains why the mainstream study of the cognitive impact of television on children suffers from two reductionist tendencies, i.e., television is understood by most researchers to be solely a technical medium, and most…

  17. What impact do posters have on academic knowledge transfer? A pilot survey on author attitudes and experiences

    PubMed Central

    2009-01-01

    Background Research knowledge is commonly facilitated at conferences via oral presentations, poster presentations and workshops. Current literature exploring the efficacy of academic posters is however limited. The purpose of this initial study was to explore the perceptions of academic poster presentation, together with its benefits and limitations as an effective mechanism for academic knowledge transfer and contribute to the available academic data. Methods A survey was distributed to 88 delegates who presented academic posters at two Releasing Research and Enterprise Potential conferences in June 2007 and June 2008 at Bournemouth University. This survey addressed attitude and opinion items, together with their general experiences of poster presentations. Descriptive statistics were performed on the responses. Results A 39% return was achieved with the majority of respondents believing that posters are a good medium for transferring knowledge and a valid form of academic publication. Visual appeal was cited as more influential than subject content, with 94% agreeing that poster imagery is most likely to draw viewer's attention. Respondents also believed that posters must be accompanied by their author in order to effectively communicate the academic content. Conclusion This pilot study is the first to explore perceptions of the academic poster as a medium for knowledge transfer. Given that academic posters rely heavily on visual appeal and direct author interaction, the medium requires greater flexibility in their design to promote effective knowledge transfer. This paper introduces the concept of the IT-based 'MediaPoster' so as to address the issues raised within published literature and subsequently enhance knowledge-transfer within the field of academic medicine. PMID:19995448

  18. Brain stem slice conditioned medium contains endogenous BDNF and GDNF that affect neural crest boundary cap cells in co-culture.

    PubMed

    Kaiser, Andreas; Kale, Ajay; Novozhilova, Ekaterina; Siratirakun, Piyaporn; Aquino, Jorge B; Thonabulsombat, Charoensri; Ernfors, Patrik; Olivius, Petri

    2014-05-30

    Conditioned medium (CM), made by collecting medium after a few days in cell culture and then re-using it to further stimulate other cells, is a known experimental concept since the 1950s. Our group has explored this technique to stimulate the performance of cells in culture in general, and to evaluate stem- and progenitor cell aptitude for auditory nerve repair enhancement in particular. As compared to other mediums, all primary endpoints in our published experimental settings have weighed in favor of conditioned culture medium, where we have shown that conditioned culture medium has a stimulatory effect on cell survival. In order to explore the reasons for this improved survival we set out to analyze the conditioned culture medium. We utilized ELISA kits to investigate whether brain stem (BS) slice CM contains any significant amounts of brain-derived neurotrophic factor (BDNF) and glial cell derived neurotrophic factor (GDNF). We further looked for a donor cell with progenitor characteristics that would be receptive to BDNF and GDNF. We chose the well-documented boundary cap (BC) progenitor cells to be tested in our in vitro co-culture setting together with cochlear nucleus (CN) of the BS. The results show that BS CM contains BDNF and GDNF and that survival of BC cells, as well as BC cell differentiation into neurons, were enhanced when BS CM were used. Altogether, we conclude that BC cells transplanted into a BDNF and GDNF rich environment could be suitable for treatment of a traumatized or degenerated auditory nerve. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Associations between Culturally Relevant Recruitment Strategies and Participant Interest, Enrollment and Generalizability in a Weight-loss Intervention for African American Families.

    PubMed

    Huffman, Lauren E; Wilson, Dawn K; Kitzman-Ulrich, Heather; Lyerly, Jordan E; Gause, Haylee M; Resnicow, Ken

    2016-07-21

    Culturally relevant recruitment strategies may be an important approach for recruiting ethnic minorities for interventions. Previous research has examined associations between recruitment strategies and enrollment of African Americans (AA), but has not explored more deeply the role of incorporating sociocultural values into recruitment strategies. Our current study explores whether sociocultural recruitment mediums were associated with demographics, interest and enrollment in a weight-loss intervention. Sociocultural mediums included community partnerships, culturally relevant ads, sociocultural events, or word-of-mouth. Non-sociocultural mediums included community/school events that did not specifically target AAs. Analyses examined whether demographics of enrolled families differed by recruitment strategy and if recruitment strategy predicted scheduling a baseline visit, enrolling in a run-in phase, and enrolling in the intervention program. Families recruited from culturally relevant ads, sociocultural events, or word-of-mouth were 1.96 times more likely to schedule a baseline visit (OR=1.96, 95% CI=1.05, 3.68) than families recruited from non-sociocultural mediums. No differences were found for sociocultural mediums on enrolling in the run-in phase or the intervention. However, among enrolled families, those recruited from sociocultural mediums were less likely to be employed (X(2) [1, N=142] =5.53, P<.05) and more likely to have lower income (X(2) [1, N=142] =13.57, P<.05). Sociocultural mediums were associated with scheduling a baseline visit, but not enrollment. They were, however, effective in recruiting a more generalizable sample among enrolled participants based on demographic characteristics. Integrating sociocultural values into recruitment methods may be a valuable strategy for increasing interest in participation among underrepresented AA families.

  20. Ionizing radiation-induced bystander mutagenesis and adaptation: Quantitative and temporal aspects

    PubMed Central

    Zhang, Ying; Zhou, Junqing; Baldwin, Joseph; Held, Kathryn D; Prise, Kevin M; Redmond, Robert W.; Liber, Howard L.

    2009-01-01

    This work explores several quantitative aspects of radiation-induced bystander mutagenesis in WTK1 human lymphoblast cells. Gamma-irradiation of cells was used to generate conditioned medium containing bystander signals, and that medium was transferred onto naïve recipient cells. Kinetic studies revealed that it required up to one hour to generate sufficient signal to induce the maximal level of mutations at the thymidine kinase locus in the bystander cells receiving the conditioned medium. Furthermore, it required at least one hour of exposure to the signal in the bystander cells to induce mutations. Bystander signal was fairly stable in the medium, requiring 12–24 hours to diminish. Medium that contained bystander signal was rendered ineffective by a 4-fold dilution; in contrast a greater than 20-fold decrease in the cell number irradiated to generate a bystander signal was needed to eliminate bystander-induced mutagenesis. This suggested some sort of feedback inhibition by bystander signal that prevented the signaling cells from releasing more signal. Finally, an ionizing radiation-induced adaptive response was shown to be effective in reducing bystander mutagenesis; in addition, low levels of exposure to bystander signal in the transferred medium induced adaptation that was effective in reducing mutations induced by subsequent γ-ray exposures. PMID:19695271

  1. Challenges in the doctor-patient relationship: 12 tips for more effective peer group discussion.

    PubMed

    Wilson, Hamish

    2015-09-01

    In New Zealand, almost all general practitioners are members of peer groups, which provide opportunities for both clinical discussion and collegial support. This article proposes that peer groups can also be a useful medium for exploring specific challenges within the doctor-patient relationship. However, the peer group culture needs to be receptive to this particular goal. Structured discussion can help peer group members explore interpersonal issues more thoroughly.

  2. Three-dimensional Čerenkov tomography of energy deposition from ionizing radiation beams.

    PubMed

    Glaser, Adam K; Voigt, William H A; Davis, Scott C; Zhang, Rongxiao; Gladstone, David J; Pogue, Brian W

    2013-03-01

    Since its discovery during the 1930s the Čerenkov effect (light emission from charged particles traveling faster than the local speed of light in a dielectric medium) has been paramount in the development of high-energy physics research. The ability of the emitted light to describe a charged particle's trajectory, energy, velocity, and mass has allowed scientists to study subatomic particles, detect neutrinos, and explore the properties of interstellar matter. However, to our knowledge, all applications of the process to date have focused on the identification of particles themselves, rather than their effect upon the surroundings through which they travel. Here we explore a novel application of the Čerenkov effect for the recovery of the spatial distribution of ionizing radiation energy deposition in a medium and apply it to the issue of dose determination in medical physics. By capturing multiple projection images of the Čerenkov light induced by a medical linear accelerator x-ray photon beam, we demonstrate the successful three-dimensional tomographic reconstruction of the imparted dose distribution.

  3. Electromagnetically Induced Transparency In Rydberg Atomic Medium

    NASA Astrophysics Data System (ADS)

    Deng, Li; Cong, Lu; Chen, Ai-Xi

    2018-03-01

    Due to possessing big principal quantum number, Rydberg atom has some unique properties, for example: its radiative lifetime is long, dipole moment is large, and interaction between atoms is strong and so on. These properties make one pay attention to Rydberg atoms. In this paper we investigate the effects of Rydberg dipole-dipole interactions on electromagnetically induced transparency (EIT) schemes and group velocity in three-level systems of ladder type, which provides theoretical foundation for exploring the linear and nonlinear characteristics of light in a Rydberg electromagnetically-induced-transparency medium.

  4. Mining microarray datasets in nutrition: expression of the GPR120 (n-3 fatty acid receptor/sensor) gene is down-regulated in human adipocytes by macrophage secretions.

    PubMed

    Trayhurn, Paul; Denyer, Gareth

    2012-01-01

    Microarray datasets are a rich source of information in nutritional investigation. Targeted mining of microarray data following initial, non-biased bioinformatic analysis can provide key insight into specific genes and metabolic processes of interest. Microarrays from human adipocytes were examined to explore the effects of macrophage secretions on the expression of the G-protein-coupled receptor (GPR) genes that encode fatty acid receptors/sensors. Exposure of the adipocytes to macrophage-conditioned medium for 4 or 24 h had no effect on GPR40 and GPR43 expression, but there was a marked stimulation of GPR84 expression (receptor for medium-chain fatty acids), the mRNA level increasing 13·5-fold at 24 h relative to unconditioned medium. Importantly, expression of GPR120, which encodes an n-3 PUFA receptor/sensor, was strongly inhibited by the conditioned medium (15-fold decrease in mRNA at 24 h). Macrophage secretions have major effects on the expression of fatty acid receptor/sensor genes in human adipocytes, which may lead to an augmentation of the inflammatory response in adipose tissue in obesity.

  5. Mining microarray datasets in nutrition: expression of the GPR120 (n-3 fatty acid receptor/sensor) gene is down-regulated in human adipocytes by macrophage secretions

    PubMed Central

    Trayhurn, Paul; Denyer, Gareth

    2012-01-01

    Microarray datasets are a rich source of information in nutritional investigation. Targeted mining of microarray data following initial, non-biased bioinformatic analysis can provide key insight into specific genes and metabolic processes of interest. Microarrays from human adipocytes were examined to explore the effects of macrophage secretions on the expression of the G-protein-coupled receptor (GPR) genes that encode fatty acid receptors/sensors. Exposure of the adipocytes to macrophage-conditioned medium for 4 or 24 h had no effect on GPR40 and GPR43 expression, but there was a marked stimulation of GPR84 expression (receptor for medium-chain fatty acids), the mRNA level increasing 13·5-fold at 24 h relative to unconditioned medium. Importantly, expression of GPR120, which encodes an n-3 PUFA receptor/sensor, was strongly inhibited by the conditioned medium (15-fold decrease in mRNA at 24 h). Macrophage secretions have major effects on the expression of fatty acid receptor/sensor genes in human adipocytes, which may lead to an augmentation of the inflammatory response in adipose tissue in obesity. PMID:25191551

  6. Exploring the feasibility of focusing CW light through a scattering medium into closely spaced twin peaks via numerical solutions of Maxwell’s equations

    NASA Astrophysics Data System (ADS)

    Tseng, Snow H.; Chang, Shih-Hui

    2018-04-01

    Here we present a numerical simulation to analyze the effect of scattering on focusing light into closely-spaced twin peaks. The pseudospectral time-domain (PSTD) is implemented to model continuous-wave (CW) light propagation through a scattering medium. Simulations show that CW light can propagate through a scattering medium and focus into closely-spaced twin peaks. CW light of various wavelengths focusing into twin peaks with sub-diffraction spacing is simulated. In advance, light propagation through scattering media of various number densities is simulated to decipher the dependence of CW light focusing phenomenon on the scattering medium. The reported simulations demonstrate the feasibility of focusing CW light into twin peaks with sub-diffraction dimensions. More importantly, based upon numerical solutions of Maxwell’s equations, research findings show that the sub-diffraction focusing phenomenon can be achieved with scarce or densely-packed scattering media.

  7. STD 105: Process Groups as an Instructional Medium for Re-entry Women at Paul D. Camp Community College.

    ERIC Educational Resources Information Center

    Creamer, Elizabeth; Duggin, Molly; Kidd, Ronald

    1999-01-01

    An effective team-based, group-oriented personal development from a woman's perspective course explores the effects of several issues on the re-entry woman: the role that society and culture play in influencing women's vocational choices; women's roles; the economic necessity of work; stress; and relationships. A team-based approach provides a…

  8. Addressing Students' Alternative Conceptions on the Propagation of Periodic Waves Using a Refutational Text

    ERIC Educational Resources Information Center

    Caleon, Imelda; Subramaniam, R.

    2013-01-01

    The effectiveness of a refutational text in addressing the alternative conceptions held by secondary school students on the topic of wave propagation in an elastic medium was explored in this study. The refutational text, which was 816 words long and featured the particle-spring model, was found to be more effective in promoting conceptual change…

  9. Responses of Four Adolescent Females to Adolescent Fiction with Strong Female Characters.

    ERIC Educational Resources Information Center

    Carico, Kathleen M.

    A study examined the effects of a reader response approach to literature in which literature is viewed as a medium for exploration and the effects of such an approach on a group of young women. Subjects of the study were four female middle school students, with the adult female researcher as participant observer. Books chosen for…

  10. Geospatial analysis of bicycle network "level of traffic stress", bicycle mode choice behavior, and bicycle crashes for risk factor identification.

    DOT National Transportation Integrated Search

    2015-08-01

    Small and medium-sized cities need publicly acceptable criteria for bicycle infrastructure improvements. This report explores the : effectiveness of one proposed system of bicycle infrastructure criteria using data from a state-of-the-art travel surv...

  11. Presidential Elections in the Age of Television.

    ERIC Educational Resources Information Center

    Rothwell, Jennifer Truran

    2000-01-01

    Explores the role of television in politics providing historical examples of the use of television and its possible effects on elections. Focuses on television as the dominant medium for politics, the connections among television, advertising, and political money, and ideas for reforming the electoral process. Includes a teaching activity on…

  12. The effect of loving-kindness meditation on positive emotions: a meta-analytic review.

    PubMed

    Zeng, Xianglong; Chiu, Cleo P K; Wang, Rong; Oei, Tian P S; Leung, Freedom Y K

    2015-01-01

    While it has been suggested that loving-kindness meditation (LKM) is an effective practice for promoting positive emotions, the empirical evidence in the literature remains unclear. Here, we provide a systematic review of 24 empirical studies (N = 1759) on LKM with self-reported positive emotions. The effect of LKM on positive emotions was estimated with meta-analysis, and the influence of variations across LKM interventions was further explored with subgroup analysis and meta-regression. The meta-analysis showed that (1) medium effect sizes for LKM interventions on daily positive emotions in both wait-list controlled RCTs and non-RCT studies; and (2) small to large effect sizes for the on-going practice of LKM on immediate positive emotions across different comparisons. Further analysis showed that (1) interventions focused on loving-kindness had medium effect size, but interventions focused on compassion showed small effect sizes; (2) the length of interventions and the time spent on meditation did not influence the effect sizes, but the studies without didactic components in interventions had small effect sizes. A few individual studies reported that the nature of positive emotions and individual differences also influenced the results. In sum, LKM practice and interventions are effective in enhancing positive emotions, but more studies are needed to identify the active components of the interventions, to compare different psychological operations, and to explore the applicability in clinical populations.

  13. The effect of loving-kindness meditation on positive emotions: a meta-analytic review

    PubMed Central

    Zeng, Xianglong; Chiu, Cleo P. K.; Wang, Rong; Oei, Tian P. S.; Leung, Freedom Y. K.

    2015-01-01

    While it has been suggested that loving-kindness meditation (LKM) is an effective practice for promoting positive emotions, the empirical evidence in the literature remains unclear. Here, we provide a systematic review of 24 empirical studies (N = 1759) on LKM with self-reported positive emotions. The effect of LKM on positive emotions was estimated with meta-analysis, and the influence of variations across LKM interventions was further explored with subgroup analysis and meta-regression. The meta-analysis showed that (1) medium effect sizes for LKM interventions on daily positive emotions in both wait-list controlled RCTs and non-RCT studies; and (2) small to large effect sizes for the on-going practice of LKM on immediate positive emotions across different comparisons. Further analysis showed that (1) interventions focused on loving-kindness had medium effect size, but interventions focused on compassion showed small effect sizes; (2) the length of interventions and the time spent on meditation did not influence the effect sizes, but the studies without didactic components in interventions had small effect sizes. A few individual studies reported that the nature of positive emotions and individual differences also influenced the results. In sum, LKM practice and interventions are effective in enhancing positive emotions, but more studies are needed to identify the active components of the interventions, to compare different psychological operations, and to explore the applicability in clinical populations. PMID:26579061

  14. Age of Acquisition and Word Frequency Effects in Picture Naming: A Dual-Task Investigation

    ERIC Educational Resources Information Center

    Dent, Kevin; Johnston, Robert A.; Humphreys, Glyn W.

    2008-01-01

    In 2 experiments, the authors explored age of acquisition (AoA) and word frequency (WF) effects in picture naming using the psychological refractory period paradigm. In Experiment 1, participants named a picture and then, a short time later, categorized 1 of 3 possible auditory tones as high, medium, or low. Both AoA (Experiment 1A) and WF…

  15. Memory bias for negative emotional words in recognition memory is driven by effects of category membership

    PubMed Central

    White, Corey N.; Kapucu, Aycan; Bruno, Davide; Rotello, Caren M.; Ratcliff, Roger

    2014-01-01

    Recognition memory studies often find that emotional items are more likely than neutral items to be labeled as studied. Previous work suggests this bias is driven by increased memory strength/familiarity for emotional items. We explored strength and bias interpretations of this effect with the conjecture that emotional stimuli might seem more familiar because they share features with studied items from the same category. Categorical effects were manipulated in a recognition task by presenting lists with a small, medium, or large proportion of emotional words. The liberal memory bias for emotional words was only observed when a medium or large proportion of categorized words were presented in the lists. Similar, though weaker, effects were observed with categorized words that were not emotional (animal names). These results suggest that liberal memory bias for emotional items may be largely driven by effects of category membership. PMID:24303902

  16. Memory bias for negative emotional words in recognition memory is driven by effects of category membership.

    PubMed

    White, Corey N; Kapucu, Aycan; Bruno, Davide; Rotello, Caren M; Ratcliff, Roger

    2014-01-01

    Recognition memory studies often find that emotional items are more likely than neutral items to be labelled as studied. Previous work suggests this bias is driven by increased memory strength/familiarity for emotional items. We explored strength and bias interpretations of this effect with the conjecture that emotional stimuli might seem more familiar because they share features with studied items from the same category. Categorical effects were manipulated in a recognition task by presenting lists with a small, medium or large proportion of emotional words. The liberal memory bias for emotional words was only observed when a medium or large proportion of categorised words were presented in the lists. Similar, though weaker, effects were observed with categorised words that were not emotional (animal names). These results suggest that liberal memory bias for emotional items may be largely driven by effects of category membership.

  17. Competitive Strategy and Influences on E-Learning in Entrepreneur-Led SMEs

    ERIC Educational Resources Information Center

    Roffe, Ian

    2007-01-01

    Purpose: To explore the influence of competitive strategy in entrepreneur-led SMEs and the effects on e-learning HRD. Design/methodology/approach: Performance consulting company reviews provide holistic information on nine case studies on small and medium sized enterprises drawn from the printing, agri-foods and media industries. Findings:…

  18. Black hole superradiance and polarization-dependent bending of light

    NASA Astrophysics Data System (ADS)

    Plascencia, Alexis D.; Urbano, Alfredo

    2018-04-01

    An inhomogeneous pseudo-scalar field configuration behaves like an optically active medium. Consequently, if a light ray passes through an axion cloud surrounding a Kerr black hole, it may experience a polarization-dependent bending. We explore the size and relevance of such effect considering both the QCD axion and a generic axion-like particle.

  19. Photonuclear activation of pure isotopic mediums.

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

    Grohman, Mark A.; Lukosi, Eric Daniel

    2010-06-01

    This work simulated the response of idealized isotopic U-235, U-238, Th-232, and Pu-239 mediums to photonuclear activation with various photon energies. These simulations were conducted using MCNPX version 2.6.0. It was found that photon energies between 14-16 MeV produce the highest response with respect to neutron production rates from all photonuclear reactions. In all cases, Pu-239 responds the highest, followed by U-238. Th-232 produces more overall neutrons at lower photon energies then U-235 when material thickness is above 3.943 centimeters. The time it takes each isotopic material to reach stable neutron production rates in time is directly proportional to themore » material thickness and stopping power of the medium, where thicker mediums take longer to reach stable neutron production rates and thinner media display a neutron production plateau effect, due to the lack of significant attenuation of the activating photons in the isotopic mediums. At this time, no neutron sensor system has time resolutions capable of verifying these simulations, but various indirect methods are possible and should be explored for verification of these results.« less

  20. An Innovative Design of a Clay-Zeolite Medium for the Adsorption of Total Phosphorus from Wastewater.

    PubMed

    Ciosek, Amanda Lidia; Luk, Grace K; Warner, Michèle; Warner, R Anthony

    2016-02-01

    Phosphorus significantly influences the eutrophication process, modifying the quality of waterways and habitat, especially in stagnant waterbodies exposed to septic tank effluent at high nutrient levels. This research explores the development of a cost-effective, efficient, and affordable on-site wastewater treatment system targeted as total phosphorus (TP) removal technology. The research objective is to demonstrate the TP removal efficiency of an optimized clay-zeolite medium by chemical adsorption. The study observes the effects of pellet medium design and modifications, influent concentrations, and contact time. Following various stages of optimization, the preliminary testing achieves a 45 ± 1.8% removal after 45 minutes of contact time. The optimized pellets are contained within a five-layer bench-scale model, achieving equilibrium TP removal of 72 ± 2.9% after 3 hours. Theoretical extrapolation to 12 contact hours indicates an achievement of 88% removal is possible. The results show a positive correlation with the linearized Langmuir and Freundlich adsorption isotherms.

  1. Wave propagation in media having negative permittivity and permeability.

    PubMed

    Ziolkowski, R W; Heyman, E

    2001-11-01

    Wave propagation in a double negative (DNG) medium, i.e., a medium having negative permittivity and negative permeability, is studied both analytically and numerically. The choices of the square root that leads to the index of refraction and the wave impedance in a DNG medium are determined by imposing analyticity in the complex frequency domain, and the corresponding wave properties associated with each choice are presented. These monochromatic concepts are then tested critically via a one-dimensional finite difference time domain (FDTD) simulation of the propagation of a causal, pulsed plane wave in a matched, lossy Drude model DNG medium. The causal responses of different spectral regimes of the medium with positive or negative refractive indices are studied by varying the carrier frequency of narrowband pulse excitations. The smooth transition of the phenomena associated with a DNG medium from its early-time nondispersive behavior to its late-time monochromatic response is explored with wideband pulse excitations. These FDTD results show conclusively that the square root choice leading to a negative index of refraction and positive wave impedance is the correct one, and that this choice is consistent with the overall causality of the response. An analytical, exact frequency domain solution to the scattering of a wave from a DNG slab is also given and is used to characterize several physical effects. This solution is independent of the choice of the square roots for the index of refraction and the wave impedance, and thus avoids any controversy that may arise in connection with the signs of these constituents. The DNG slab solution is used to critically examine the perfect lens concept suggested recently by Pendry. It is shown that the perfect lens effect exists only under the special case of a DNG medium with epsilon(omega)=mu(omega)=-1 that is both lossless and nondispersive. Otherwise, the closed form solutions for the field structure reveal that the DNG slab converts an incident spherical wave into a localized beam field whose parameters depend on the values of epsilon and mu. This beam field is characterized with a paraxial approximation of the exact DNG slab solution. These monochromatic concepts are again explored numerically via a causal two-dimensional FDTD simulation of the scattering of a pulsed cylindrical wave by a matched, lossy Drude model DNG slab. These FDTD results demonstrate conclusively that the monochromatic electromagnetic power flow through the DNG slab is channeled into beams rather then being focused and, hence, the Pendry perfect lens effect is not realizable with any realistic metamaterial.

  2. Effects of medium components and culture conditions on mycelial biomass and the production of bioactive ingredients in submerged culture of Xylaria nigripes (Ascomycetes), a Chinese medicinal fungus.

    PubMed

    Chen, Jian-Zhi; Lo, Hui-Chen; Lin, Fang-Yi; Chang, Shih-Liang; Hsieh, Changwei; Liang, Zeng-Chin; Ho, Wai-Jane; Hsu, Tai-Hao

    2014-01-01

    The optimal culture conditions were investigated to maximize the production of mycelial biomass and bioactive ingredients in submerged cultivation of Xylaria nigripes, a Chinese medicinal fungus. The one-factor-at-a-time method was used to explore the effects of medium components, including carbon, nitrogen, mineral sources, and initial pH of the medium and environmental factors, such as culture temperature and rotation speed, on mycelial growth and production of bioactive ingredients. The results indicated that the optimal culture temperature and rotation speed were 25°C and 100 rpm in a medium with 20 g fructose, 6 g yeast extract, and 2 g magnesiun sulfate heptahydrate as carbon, nitrogen, and mineral sources, respectively, in 1 L distilled water with an initial medium pH of 5.5. With optimal medium components and conditions of cultivation, the maximal production of mycelial biomass was 6.64 ± 0.88 g/L, with maximal production of bioactive ingredients such as extracellular polysaccharides (2.36 ± 0.18 mg/mL), intracellular polysaccharides (2.38 ± 0.07 mg/g), adenosine (43.27 ± 2.37 mg/g), total polyphenols (36.57 ± 1.36 mg/g), and triterpenoids (31.29 ± 1.17 mg/g) in a shake flask culture. These results suggest that different bioactive ingredients including intracellular polysaccharides, adenosine, total polyphenols and triterpenoids in mycelia and extracellular polysaccharides in broth can be obtained from one simple medium for submerged cultivation of X. nigripes.

  3. Managers' Understanding of Workplace Health Promotion within Small and Medium-Sized Enterprises: A Phenomenological Study

    ERIC Educational Resources Information Center

    Moore, Ann; Parahoo, Kader; Fleming, Paul

    2011-01-01

    Objective: This study aimed at exploring managers' understanding of workplace health promotion and experiences of workplace health promotion activity within small and medium-sized enterprises. Design: A Heideggerian interpretive phenomenological methodology was adopted. Setting: This study was undertaken with small and medium-sized enterprise…

  4. Genome-wide analysis of nuclear magnetic resonance metabolites revealed parent-of-origin effect on triglycerides in medium very low-density lipoprotein in PTPRD gene.

    PubMed

    Pervjakova, N; Kukushkina, V; Haller, T; Kasela, S; Joensuu, A; Kristiansson, K; Annilo, T; Perola, M; Salomaa, V; Jousilahti, P; Metspalu, A; Mägi, R

    2018-05-01

    The aim of the study was to explore the parent-of-origin effects (POEs) on a range of human nuclear magnetic resonance metabolites. We search for POEs in 14,815 unrelated individuals from Estonian and Finnish cohorts using POE method for the genotype data imputed with 1000 G reference panel and 82 nuclear magnetic resonance metabolites. Meta-analysis revealed the evidence of POE for the variant rs1412727 in PTPRD gene for the metabolite: triglycerides in medium very low-density lipoprotein. No POEs were detected for genetic variants that were previously known to have main effect on circulating metabolites. We demonstrated possibility to detect POEs for human metabolites, but the POEs are weak, and therefore it is hard to detect those using currently available sample sizes.

  5. Exploring the cost-utility of stratified primary care management for low back pain compared with current best practice within risk-defined subgroups.

    PubMed

    Whitehurst, David G T; Bryan, Stirling; Lewis, Martyn; Hill, Jonathan; Hay, Elaine M

    2012-11-01

    Stratified management for low back pain according to patients' prognosis and matched care pathways has been shown to be an effective treatment approach in primary care. The aim of this within-trial study was to determine the economic implications of providing such an intervention, compared with non-stratified current best practice, within specific risk-defined subgroups (low-risk, medium-risk and high-risk). Within a cost-utility framework, the base-case analysis estimated the incremental healthcare cost per additional quality-adjusted life year (QALY), using the EQ-5D to generate QALYs, for each risk-defined subgroup. Uncertainty was explored with cost-utility planes and acceptability curves. Sensitivity analyses were performed to consider alternative costing methodologies, including the assessment of societal loss relating to work absence and the incorporation of generic (ie, non-back pain) healthcare utilisation. The stratified management approach was a cost-effective treatment strategy compared with current best practice within each risk-defined subgroup, exhibiting dominance (greater benefit and lower costs) for medium-risk patients and acceptable incremental cost to utility ratios for low-risk and high-risk patients. The likelihood that stratified care provides a cost-effective use of resources exceeds 90% at willingness-to-pay thresholds of £4000 (≈ 4500; $6500) per additional QALY for the medium-risk and high-risk groups. Patients receiving stratified care also reported fewer back pain-related days off work in all three subgroups. Compared with current best practice, stratified primary care management for low back pain provides a highly cost-effective use of resources across all risk-defined subgroups.

  6. Modeling, simulation, and concept design for hybrid-electric medium-size military trucks

    NASA Astrophysics Data System (ADS)

    Rizzoni, Giorgio; Josephson, John R.; Soliman, Ahmed; Hubert, Christopher; Cantemir, Codrin-Gruie; Dembski, Nicholas; Pisu, Pierluigi; Mikesell, David; Serrao, Lorenzo; Russell, James; Carroll, Mark

    2005-05-01

    A large scale design space exploration can provide valuable insight into vehicle design tradeoffs being considered for the U.S. Army"s FMTV (Family of Medium Tactical Vehicles). Through a grant from TACOM (Tank-automotive and Armaments Command), researchers have generated detailed road, surface, and grade conditions representative of the performance criteria of this medium-sized truck and constructed a virtual powertrain simulator for both conventional and hybrid variants. The simulator incorporates the latest technology among vehicle design options, including scalable ultracapacitor and NiMH battery packs as well as a variety of generator and traction motor configurations. An energy management control strategy has also been developed to provide efficiency and performance. A design space exploration for the family of vehicles involves running a large number of simulations with systematically varied vehicle design parameters, where each variant is paced through several different mission profiles and multiple attributes of performance are measured. The resulting designs are filtered to remove dominated designs, exposing the multi-criterial surface of optimality (Pareto optimal designs), and revealing the design tradeoffs as they impact vehicle performance and economy. The results are not yet definitive because ride and drivability measures were not included, and work is not finished on fine-tuning the modeled dynamics of some powertrain components. However, the work so far completed demonstrates the effectiveness of the approach to design space exploration, and the results to date suggest the powertrain configuration best suited to the FMTV mission.

  7. Ionosphere total electron content and its horizontal gradients, measured on the basis of satellite signal recordings at scattered points

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

    Misyura, V.A.; Podnos, V.A.; Kapanin, I.I.

    1973-01-01

    Translated from Kosm. Issled.; 11: No. 4, 581-585(1973). The integrated electron content of the ionosphere up to the level of the recording satellite, and the horizontal gradients of the integrated electron content (total, latitudinal, and longitudinal components), was obtained at scattered observation points located at medium and high latitudes, on the basis of recordings made of Doppler and Faraday effects on coherent signals from the satellites Explorer-22, Explorer-27, Interkosmos-2, Kosmos321, Kosmos-356, and Kosmos-381. (auth)

  8. Gamification and Game-Based Learning

    ERIC Educational Resources Information Center

    Karagiorgas, Dimitrios N.; Niemann, Shari

    2017-01-01

    In the last 10 years, gaming has evolved to the point that it is now being used as a learning medium to educate students in many different disciplines. The educational community has begun to explore the effectiveness of gaming as a learning tool and as a result two different ways of utilizing games for education have been created: Gamification and…

  9. The Art of Video Games

    ERIC Educational Resources Information Center

    Johnson, Mark M.

    2012-01-01

    The Smithsonian American Art Museum has created and will tour an exhibition on a most unusual but extremely popular art form--"The Art of Video Games." As one of the largest and first of its type, this exhibition will document and explore a 40-year evolution of video games as an artistic medium, with a focus on striking visual effects and the…

  10. The Effect of Brand Identification on Alumni Supportive Behaviors

    ERIC Educational Resources Information Center

    Stephenson, Amber L.

    2013-01-01

    The purpose of this study was to explore the relationship of brand identification and supportive behaviors for alumni of a medium-sized state-run public institution of higher education in the mid-Atlantic region of the US. The research examined the perceptions of donor and non-donor alumni of a state-run public institution of higher education to…

  11. Reading across Mediums: Effects of Reading Digital and Print Texts on Comprehension and Calibration

    ERIC Educational Resources Information Center

    Singer, Lauren M.; Alexander, Patricia A.

    2017-01-01

    This study explored differences that might exist in comprehension when students read digital and print texts. Ninety undergraduates read both digital and print versions of newspaper articles and book excerpts on topics of childhood ailments. Prior to reading texts in counterbalanced order, topic knowledge was assessed and students were asked to…

  12. Performance Funding Policy Effects on Community College Outcomes: Are Short-Term Certificates on the Rise?

    ERIC Educational Resources Information Center

    Li, Amy Y.; Kennedy, Alec I.

    2018-01-01

    Objective: Performance funding (PF) policies allocate a portion of state funding to colleges based on student outcomes. This study is the first to account for policy type and design differences, and explores the impact of performance funding on three levels of credential completions: short-term certificates, medium-term certificates, and…

  13. The Effect of Training in Visual Composition on Organization in Written Composition in Grade III.

    ERIC Educational Resources Information Center

    Tuttle, Frederick B., Jr.

    The purpose of this investigation was to explore the possibility that one technique for improvement of organization in written composition might be instruction in the organizational process of another medium, such as sequencing photographs meaningfully. Two methods of improving organization in written composition were compared. The first was a…

  14. The Relation between Mastery Goals and Intrinsic Motivation among University Students: A Longitudinal Study

    ERIC Educational Resources Information Center

    Bieg, Sonja; Reindl, Marion; Dresel, Markus

    2017-01-01

    The present work broadens previous research on students' mastery goals and intrinsic motivation by exploring their reciprocal effects using a longitudinal approach. To this end, a study using four measurement points was conducted during 10 weeks of one semester. The sample comprised 1156 students enrolled in psychology courses at a medium-sized…

  15. The Internet as a Medium of Training for Picture Archival and Communication Systems (PACS).

    ERIC Educational Resources Information Center

    Majid, Shaheen; Misra, Ramesh Kumar

    2002-01-01

    Explores the potential of Web-based training for PACS (Picture Archival and Communication Systems) used in radiology departments for the storage and archiving of patients' medical images. Reports results of studies in three hospitals in Malaysia, Singapore and the Philippines that showed that the Internet can be used effectively for training.…

  16. Visual Medium in the Service and Disservice of Education

    ERIC Educational Resources Information Center

    Wong, Wan-chi

    2001-01-01

    There are different ways of exploring and examining the visual medium in the service and disservice of education. A discursive form rather than a visual medium is chosen in this attempt. Utilizing the conceptualizations of Suzanne Langer, Christine Nystrom observed that American symbolic environments have undergone a massive shift from discursive…

  17. The Advanced Energetic Pair Telescope (AdEPT}: A Future Medium-Energy Gamma-Ray Balloon (and Explorer?) Mission

    NASA Technical Reports Server (NTRS)

    Hunter, Stanley D.

    2011-01-01

    Gamma-ray astrophysics probes the highest energy, exotic phenomena in astrophysics. In the medium-energy regime, 0.1-200 MeV, many astrophysical objects exhibit unique and transitory behavior such as the transition from electron dominated to hadron dominated processes, spectral breaks, bursts, and flares. Medium-energy gamma-ray imaging however, continues to be a major challenge particularly because of high background, low effective area, and low source intensities. The sensitivity and angular resolution required to address these challenges requires a leap in technology. The Advance Energetic Pair Telescope (AdEPT) being developed at GSFC is designed to image gamma rays above 5 MeV via pair production with angular resolution of 1-10 deg. In addition AdEPT will, for the first time, provide high polarization sensitivity in this energy range. This performance is achieved by reducing the effective area in favor of enhanced angular resolution through the use of a low-density gaseous conversion medium. AdEPT is based on the Three-Dimensional Track Imager (3-DTI) technology that combines a large volume Negative Ion Time Projection Chamber (NITPC) with 2-D Micro-Well Detector (MWD) readout. I will review the major science topics addressable with medium-energy gamma-rays and discuss the current status of the AdEPT technology, a proposed balloon instrument, and the design of a future satellite mission.

  18. Reducing the Geothermal Exploration Risk by Carbon Dioxide Soil Flux Investigations

    NASA Astrophysics Data System (ADS)

    Carapezza, Maria Luisa; Barberi, Franco; Ranaldi, Massimo; Ricci, Tullio; Tarchini, Luca; De Simone, Gabriele; Gattuso, Alessandro; Silvestri, Mario

    2013-04-01

    In the exploration of medium to high enthalpy geothermal resources it happens rather frequently that deep wells find high temperatures but are not productive because they don't cross any permeable fractured reservoir. Because of the high cost of deep drillings, this aspect represents one of the main economic risks of geothermal exploration. A detailed survey of diffuse CO2 soil flux may allow to identify from the surface the permeable portions of a deep-seated actively degassing geothermal reservoir, drastically reducing this risk. In order to test the effectiveness of CO2 soil flux as a geothermal exploration tool we selected two volcanic areas north of Rome, Latera caldera and Marta zone near lake Bolsena, both hosting a geothermal reservoir with T>200 °C and where productive and non-productive wells had been drilled in the past. We proved that in both zones productive wells are located on high CO2 soil flux zones, whereas the not-productive wells are sited on low flux areas. In addition the surveys allowed to identify some as yet unexplored portions of the geothermal reservoirs where future wells should be conveniently located. Use of the same technique in the medium enthalpy geothermal system of Torre Alfina, Central Italy (T=140°C) showed that the presence of a thick impervious rock cover may be very effective in preventing gas leakages from the reservoir to the surface. Promising results have been obtained also by CO2 soil flux surveys in some geothermal areas of Honduras (Platanares, Azacualpa) and Costa Rica (Las Pailas). Obviously, CO2 flux cannot provide any estimate of temperature at depth, which has to be assessed with other geochemical or geophysical exploration techniques.

  19. The interstellar medium and star formation of galactic disks. I. Interstellar medium and giant molecular cloud properties with diffuse far-ultraviolet and cosmic-ray backgrounds

    NASA Astrophysics Data System (ADS)

    Li, Qi; Tan, Jonathan C.; Christie, Duncan; Bisbas, Thomas G.; Wu, Benjamin

    2018-05-01

    We present a series of adaptive mesh refinement hydrodynamic simulations of flat rotation curve galactic gas disks, with a detailed treatment of the interstellar medium (ISM) physics of the atomic to molecular phase transition under the influence of diffuse far-ultraviolet (FUV) radiation fields and cosmic-ray backgrounds. We explore the effects of different FUV intensities, including a model with a radial gradient designed to mimic the Milky Way. The effects of cosmic rays, including radial gradients in their heating and ionization rates, are also explored. The final simulations in this series achieve 4 pc resolution across the ˜20 kpc global disk diameter, with heating and cooling followed down to temperatures of ˜10 K. The disks are evolved for 300 Myr, which is enough time for the ISM to achieve a quasi-statistical equilibrium. In particular, the mass fraction of molecular gas is stabilized by ˜200 Myr. Additional global ISM properties are analyzed. Giant molecular clouds (GMCs) are also identified and the statistical properties of their populations are examined. GMCs are tracked as the disks evolve. GMC collisions, which may be a means of triggering star cluster formation, are counted and their rates are compared with analytic models. Relatively frequent GMC collision rates are seen in these simulations, and their implications for understanding GMC properties, including the driving of internal turbulence, are discussed.

  20. Mediating Inequalities: Exploring English-Medium Instruction in a Suburban Indian Village School

    ERIC Educational Resources Information Center

    Bhattacharya, Usree

    2013-01-01

    India is home to 1652 languages, but only 22 are officially recognized. And while the Constitution requires local authorities to provide mother tongue instruction in schools (Article 350A, Constitution of India), a mere 43 languages are used nationally as instructional medium. An exploding demand for English-medium schooling across socio-economic…

  1. The New Sphere of International Student Education in Chinese Higher Education: A Focus on English-Medium Degree Programs

    ERIC Educational Resources Information Center

    Kuroda, Chiharu

    2014-01-01

    This empirical study explores the current features of English-medium instructed master's degree programs for international students (EMIMDPs-ISs) in Chinese higher education. Since the mid-2000s, a significant number of Chinese universities have proactively engaged in establishing English-medium instructed degree programs for international…

  2. Exploring Uses and Gratifications: A Comparison of Reported Uses of Television and Reported Uses of Favorite Program Type.

    ERIC Educational Resources Information Center

    Bantz, Charles R.

    1982-01-01

    Results indicate respondents do not identify medium-specific or program-specific uses. Lack of differentiation suggests: (1) additional assessment of the relationship of medium and content is needed and (2) medium and content should be considered related variables in uses and gratification research, and research not incorporating their interaction…

  3. Human periodontal ligament stem cells secretome from multiple sclerosis patients suppresses NALP3 inflammasome activation in experimental autoimmune encephalomyelitis

    PubMed Central

    Soundara Rajan, Thangavelu; Giacoppo, Sabrina; Diomede, Francesca; Bramanti, Placido; Trubiani, Oriana; Mazzon, Emanuela

    2017-01-01

    Research in recent years has largely explored the immunomodulatory effects of mesenchymal stem cells (MSCs) and their secretory products, called “secretome,” in the treatment of neuroinflammatory diseases. Here, we examined whether such immunosuppressive effects might be elicited due to inflammasome inactivation. To this end, we treated experimental autoimmune encephalomyelitis (EAE) mice model of multiple sclerosis (MS) with the conditioned medium or purified exosomes/microvesicles (EMVs) obtained from relapsing-remitting-MS patients human periodontal ligament stem cells (hPDLSCs) and investigated the regulation of NALP3 inflammasome. We noticed enhanced expression of NALP3, Cleaved Caspase 1, interleukin (IL)-1β, and IL-18 in EAE mouse spinal cord. Conversely, hPDLSCs-conditioned medium and EMVs significantly blocked NALP3 inflammasome activation and provided protection from EAE. Reduction in NALP3, Cleaved Caspase 1, IL-1β, and IL-18 level was noticed in conditioned medium and EMVs-treated EAE mice. Pro-inflammatory Toll-like receptor (TLR)-4 and nuclear factor (NF)-κB were elevated in EAE, while hPDLSCs-conditioned medium and EMVs treatment reduced their expression and increased IκB-α expression. Characterization of hPDLSCs-conditioned medium showed substantial level of anti-inflammatory IL-10, transforming growth factor (TGF)-β, and stromal cell–derived factor 1α (SDF-1α). We propose that the immunosuppressive role of hPDLSCs-derived conditioned medium and EMVs in EAE mice may partly attribute to the presence of soluble immunomodulatory factors, NALP3 inflammasome inactivation, and NF-κB reduction. PMID:28764573

  4. Velocity sensitivity of seismic body waves to the anisotropic parameters of a TTI-medium

    NASA Astrophysics Data System (ADS)

    Zhou, Bing; Greenhalgh, Stewart

    2008-09-01

    We formulate the derivatives of the phase and group velocities for each of the anisotropic parameters in a tilted transversely isotropic medium (TTI-medium). This is a common geological model in seismic exploration and has five elastic moduli or related Thomsen parameters and two orientation angles defining the axis of symmetry of the rock. We present two independent methods to compute the derivatives and examine the formulae with real anisotropic rocks. The formulations and numerical computations do not encounter any singularity problem when applied to the two quasi shear waves, which is a problem with other approaches. The two methods yield the same results, which show in a quantitative way the sensitivity behaviour of the phase and the group velocities to all of the elastic moduli or Thomsen's anisotropic parameters as well as the orientation angles in the 2D and 3D cases. One can recognize the dominant (strong effect) and weak (or 'dummy') parameters for the three seismic body-wave modes (qP, qSV, qSH) and their effective domains over the whole range of phase-slowness directions. These sensitivity patterns indicate the possibility of nonlinear kinematic inversion with the three wave modes for determining the anisotropic parameters and imaging an anisotropic medium.

  5. Spontaneous electrorheological effect in nematic liquid crystals under Taylor-Couette flow configuration

    NASA Astrophysics Data System (ADS)

    Dhar, Jayabrata; Chakraborty, Suman

    2017-09-01

    Electrorheological (ER) characteristics of Nematic Liquid Crystals (NLCs) have been a topic of immense interest in the field of soft matter physics owing to its rheological modulation capabilities. Here we explore the augmentation in rheological characteristics of the nematic fluid confined within the annular region of the concentric cylindrical space with an Electrical Double Layer (EDL) induced at the fluid-substrate interface due to certain physico-chemical interactions. Using a Taylor-Couette flow configuration associated with an EDL induced at the inner cylinder wall, we show that a spontaneous electrorheological effect is generated owing to the intrinsic director anisotropy and structural order of complex nematic fluids. We seek to find the enhancement in torque transfer capability due to the inherent electrorheological nature of the nematic medium, apart from exploiting the innate nature of such homogeneous media to remain free of coagulation, a fact which makes it an excellent candidate for the applications in microfluidic environment. Our analysis reveals that with stronger induced charge density within the EDL, the apparent viscosity enhances, which, in turn, augments torque transfer across the concentric cylinder. The velocity profile tends to flatten in comparison to the classical circular Couette flow in annular geometry as one increases the surface charge density. We further observe a more pronounced ER effect for the nematic medium having larger electrical permittivity anisotropy. Besides the torque transfer qualifications, we also explore the distinct scenarios, wherein the same NLC medium exhibits shear thinning and shear thickening characteristics. The present configuration of the efficient torque transfer mechanism may be proficiently downscaled to micro-level and is relevant in the fabrication of micro-clutch and micro-dampers.

  6. Effect of in-medium nucleon-nucleon cross section on proton-proton momentum correlation in intermediate-energy heavy-ion collisions

    NASA Astrophysics Data System (ADS)

    Wang, Ting-Ting; Ma, Yu-Gang; Zhang, Chun-Jian; Zhang, Zheng-Qiao

    2018-03-01

    The proton-proton momentum correlation function from different rapidity regions is systematically investigated for the Au + Au collisions at different impact parameters and different energies from 400 A MeV to 1500 A MeV in the framework of the isospin-dependent quantum molecular dynamics model complemented by the Lednický-Lyuboshitz analytical method. In particular, the in-medium nucleon-nucleon cross-section dependence of the correlation function is brought into focus, while the impact parameter and energy dependence of the momentum correlation function are also explored. The sizes of the emission source are extracted by fitting the momentum correlation functions using the Gaussian source method. We find that the in-medium nucleon-nucleon cross section obviously influences the proton-proton momentum correlation function, which is from the whole-rapidity or projectile or target rapidity region at smaller impact parameters, but there is no effect on the mid-rapidity proton-proton momentum correlation function, which indicates that the emission mechanism differs between projectile or target rapidity and mid-rapidity protons.

  7. The rationale for advancing the formulation of azelaic acid vehicles.

    PubMed

    Draelos, Zoe Diana

    2006-02-01

    When first approved in December 2002, 15% azelaic acid (AzA) gel represented a significant advance over the available 20% AzA cream. Although a smaller amount of AzA was present in the new formulation, the gel medium provided a highly effective system for delivering the active ingredient, thus providing more effective treatment. This article explores the nature of these 2 vehicles and highlights the importance of the formulation in which dermatologic drugs are delivered.

  8. Inverse Doppler shift and control field as coherence generators for the stability in superluminal light

    NASA Astrophysics Data System (ADS)

    Ghafoor, Fazal; Bacha, Bakht Amin; Khan, Salman

    2015-05-01

    A gain-based four-level atomic medium for the stability in superluminal light propagation using control field and inverse Doppler shift as coherence generators is studied. In regimes of weak and strong control field, a broadband and multiple controllable transparency windows are, respectively, identified with significantly enhanced group indices. The observed Doppler effect for the class of high atomic velocity of the medium is counterintuitive in comparison to the effect of the class of low atomic velocity. The intensity of each of the two pump fields is kept less than the optimum limit reported in [M. D. Stenner and D. J. Gauthier, Phys. Rev. A 67, 063801 (2003), 10.1103/PhysRevA.67.063801] for stability in the superluminal light pulse. Consequently, superluminal stable domains with the generated coherence are explored.

  9. Controlled release of folic acid through liquid-crystalline folate nanoparticles.

    PubMed

    Misra, Rahul; Katyal, Henna; Mohanty, Sanat

    2014-11-01

    The present study explores folate nanoparticles as nano-carriers for controlled drug delivery. Cross-linked nanoparticles of liquid crystalline folates are composed of ordered stacks. This paper shows that the folate nanoparticles can be made with less than 5% loss in folate ions. In addition, this study shows that folate nanoparticles can disintegrate in a controlled fashion resulting in controlled release of the folate ions. Release can be controlled by the size of nanoparticles, the extent of cross-linking and the choice of cross-linking cation. The effect of different factors like agitation, pH, and temperature on folate release was also studied. Studies were also carried out to show the effect of release medium and role of ions in the release medium on disruption of folate assembly. Copyright © 2014. Published by Elsevier B.V.

  10. Medium-Energy Particle experiments (MEPs) for the Exploration of energization and Radiation in Geospace (ERG) mission

    NASA Astrophysics Data System (ADS)

    Kasahara, S.; Yokota, S.; Mitani, T.; Asamura, K.; Hirahara, M.; Shibano, Y.; Yamamoto, K.; Takashima, T.

    2017-12-01

    ERG (Exploration of energization and Radiation in Geospace) is the geospace exploration spacecraft, which was launched on 20 December 2016. The mission goal is to unveil the physics behind the drastic radiation belt variability during space storms. One of key observations is the measurement of ions and electrons in the medium-energy range (10-200 keV), since these particles excite EMIC, magnetosonic, and whistler waves, which are theoretically suggested to play significant roles in the relativistic electron acceleration and loss. Medium-Energy Particle experiments - electron analyser (MEP-e) measures the energy and the direction of each incoming electron in the range of 7 to 87 keV. The sensor covers 2π radian disk-like field-of-view with 16 detectors, and the solid angle coverage is achieved by using spacecraft spin motion. The electron energy is independently measured by an electrostatic analyser and avalanche photodiodes, enabling the significant background reduction. Medium-Energy Particle experiments - ion mass analyzer (MEP-i) measures the energy, mass, and charge state of the direction of each incoming ion in the medium-energy range (<10 to >180 keV/q). MEP-i thus provides the velocity distribution functions of medium-energy ions (e.g., protons and oxygens), from which we can obtain significant information on local ion energization and pitch angle scattering in the inner magnetosphere. Heavy ion measurements can also play an important role to restrict global mass transport including the ionosphere and the plasmasheet. Here we show the technical approaches, data output, and highlights of initial observations.

  11. Freeze fracturing of elastic porous media: a mathematical model

    PubMed Central

    Vlahou, I.; Worster, M. G.

    2015-01-01

    We present a mathematical model of the fracturing of water-saturated rocks and other porous materials in cold climates. Ice growing inside porous rocks causes large pressures to develop that can significantly damage the rock. We study the growth of ice inside a penny-shaped cavity in a water-saturated porous rock and the consequent fracturing of the medium. Premelting of the ice against the rock, which results in thin films of unfrozen water forming between the ice and the rock, is one of the dominant processes of rock fracturing. We find that the fracture toughness of the rock, the size of pre-existing faults and the undercooling of the environment are the main parameters determining the susceptibility of a medium to fracturing. We also explore the dependence of the growth rates on the permeability and elasticity of the medium. Thin and fast-fracturing cracks are found for many types of rocks. We consider how the growth rate can be limited by the existence of pore ice, which decreases the permeability of a medium, and propose an expression for the effective ‘frozen’ permeability. PMID:25792954

  12. Freeze fracturing of elastic porous media: a mathematical model.

    PubMed

    Vlahou, I; Worster, M G

    2015-03-08

    We present a mathematical model of the fracturing of water-saturated rocks and other porous materials in cold climates. Ice growing inside porous rocks causes large pressures to develop that can significantly damage the rock. We study the growth of ice inside a penny-shaped cavity in a water-saturated porous rock and the consequent fracturing of the medium. Premelting of the ice against the rock, which results in thin films of unfrozen water forming between the ice and the rock, is one of the dominant processes of rock fracturing. We find that the fracture toughness of the rock, the size of pre-existing faults and the undercooling of the environment are the main parameters determining the susceptibility of a medium to fracturing. We also explore the dependence of the growth rates on the permeability and elasticity of the medium. Thin and fast-fracturing cracks are found for many types of rocks. We consider how the growth rate can be limited by the existence of pore ice, which decreases the permeability of a medium, and propose an expression for the effective 'frozen' permeability.

  13. Statistical optimization of culture medium for production of exopolysaccharide from endophytic fungus Bionectria ochroleuca and its antitumor effect in vitro

    PubMed Central

    Li, Yun; Guo, Shoujun; Zhu, Hui

    2016-01-01

    Endophytic fungi have been recognized as possible useful sources of bioactive metabolites. However, exopolysaccharide (EPS) production from endophytic fungi and its antitumor activity have been less explored. In the present study, endophtic fungus Bionectria ochroleuca M21 was exploited for the production of EPS in submerged culture. Among tested medium components, glucose, yeast extract, MgSO4 and Tween80 were found to be effective and significant on EPS production. Response surface methodology (RSM) was employed to optimize medium composition. The results showed that the significant factors were glucose, yeast extract and Tween80. The optimal medium was observed at the composition of glucose 55.7 g/L, yeast extract 6.04 g/L, MgSO4 0.25g/L and Tween80 0.1 % (v/v). Using the optimized medium, EPS production was achieve at 2.65 ± 0.16 g/L after 4 days fermentation in a 5L bioreactor. Examination of cytotoxicity showed that the EPS from B. ochroleuca M21 did not have cytotoxic activity on human liver HL-7702 cells at concentration 0.025-1.6 mg/mL. In contrast, the EPS exhibited antiproliferative activities against cell lines of liver cancer (HepG2), gastric cancer (SGC-7901) and colon cancer (HT29) in a dose- and time-dependent manner in the concentration ranges of 0.1-0.45 mg/mL. PMID:27330527

  14. Effect of thymol in heating and recovery media on the isothermal and non-isothermal heat resistance of Bacillus spores.

    PubMed

    Esteban, Maria-Dolores; Conesa, Raquel; Huertas, Juan-Pablo; Palop, Alfredo

    2015-06-01

    Members of the genus Bacillus include important food-borne pathogen and spoilage microorganisms for food industry. Essential oils are natural products extracted from herbs and spices, which can be used as natural preservatives in many foods because of their antibacterial, antifungal, antioxidant and anti-carcinogenic properties. The aim of this research was to explore the effect of the addition of different concentrations of thymol to the heating and recovery media on the thermal resistance of spores of Bacillus cereus, Bacillus licheniformis and Bacillus subtilis at different temperatures. While the heat resistance was hardly reduced when thymol was present in the heating medium, the effect in the recovery medium was greater, reducing the D100 °C values down to one third for B. subtilis and B. cereus when 0.5 mM thymol was added. This effect was dose dependent and was also observed at other heating temperatures. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Cognitive and Occupational Function in Survivors of Adolescent Cancer.

    PubMed

    Nugent, Bethany D; Bender, Catherine M; Sereika, Susan M; Tersak, Jean M; Rosenzweig, Margaret

    2018-02-01

    Adolescents with cancer have unique developmental considerations. These include brain development, particularly in the frontal lobe, and a focus on completing education and entering the workforce. Cancer and treatment at this stage may prove to uniquely affect survivors' experience of cognitive and occupational function. An exploratory, cross-sectional, descriptive comparative study was employed to describe cognitive and occupational function in adult survivors of adolescent cancer (diagnosed between the ages of 15 and 21 years) and explore differences in age- and gender-matched controls. In total, 23 survivors and 14 controls participated in the study. While significant differences were not found between the groups on measures of cognitive and occupational function, several small and medium effect sizes were found suggesting that survivors may have greater difficulty than controls. Two small effect sizes were found in measures of neuropsychological performance (the Digit Vigilance test [d = 0.396] and Stroop test [d = 0.226]). Small and medium effect sizes ranging from 0.269 to 0.605 were found for aspects of perceived and total cognitive function. A small effect size was also found in work output (d = 0.367). While we did not find significant differences in cognitive or occupational function between survivors and controls, the effect sizes observed point to the need for future research. Future work using a larger sample size and longitudinal design are needed to further explore cognitive and occupational function in this vulnerable and understudied population and assist in the understanding of patterns of change over time.

  16. Electromagnetic radiation as a probe of the initial state and of viscous dynamics in relativistic nuclear collisions

    NASA Astrophysics Data System (ADS)

    Vujanovic, Gojko; Paquet, Jean-François; Denicol, Gabriel S.; Luzum, Matthew; Jeon, Sangyong; Gale, Charles

    2016-07-01

    The penetrating nature of electromagnetic signals makes them suitable probes to explore the properties of the strongly interacting medium created in relativistic nuclear collisions. We examine the effects of the initial conditions and shear relaxation time on the spectra and flow coefficients of electromagnetic probes, using an event-by-event 3+1-dimensional viscous hydrodynamic simulation (music).

  17. Planning for the Impacts of Highway Relief Routes on Small- and Medium-Size Communities

    DOT National Transportation Integrated Search

    2001-03-01

    This report explores possible strategies for minimizing the negative impacts and maximizing the positive impacts of highway relief routes on small- and medium-size communities in Texas. Planning strategies are identified through a : literature search...

  18. Exploring the effect of silver nanoparticle size and medium composition on uptake into pulmonary epithelial 16HBE14o-cells

    NASA Astrophysics Data System (ADS)

    Kettler, Katja; Krystek, Petra; Giannakou, Christina; Hendriks, A. Jan; de Jong, Wim H.

    2016-07-01

    The increasing number of nanotechnology products on the market poses increasing human health risks by particle exposures. Adverse effects of silver nanoparticles (AgNPs) in various cell lines have been measured based on exposure dose after a fixed time point, but NP uptake kinetics and the time-dependent internal cellular concentration are often not considered. Even though knowledge about relevant timescales for NP uptake is essential, e.g. for time- and cost-effective risk assessment through modelling, insufficient data are available. Therefore, the authors examined uptake rates for three different AgNP sizes (20, 50 and 75 nm) and two tissue culture medium compositions (with and without foetal calf serum, FCS) under realistic exposure concentrations in pulmonary epithelial 16HBE14o-cells. The quantification of Ag in cells was carried out by high-resolution inductively coupled plasma mass spectrometry. We show for the first time that uptake kinetics of AgNPs into 16HBE14o-cells was highly influenced by medium composition. Uptake into cells was higher in medium without FCS, reaching approximately twice the concentration after 24 h than in medium supplemented with FCS, showing highest uptake for 50-nm AgNPs when expressed on a mass basis. This optimum shifts to 20 nm on a number basis, stressing the importance of the measurand in which results are presented. The importance of our research identifies that not just the uptake after a certain time point should be considered as dose but also the process of uptake (timing) might need to be considered when studying the mechanism of toxicity of nanoparticles.

  19. Exploring the effect of silver nanoparticle size and medium composition on uptake into pulmonary epithelial 16HBE14o-cells.

    PubMed

    Kettler, Katja; Krystek, Petra; Giannakou, Christina; Hendriks, A Jan; de Jong, Wim H

    The increasing number of nanotechnology products on the market poses increasing human health risks by particle exposures. Adverse effects of silver nanoparticles (AgNPs) in various cell lines have been measured based on exposure dose after a fixed time point, but NP uptake kinetics and the time-dependent internal cellular concentration are often not considered. Even though knowledge about relevant timescales for NP uptake is essential, e.g. for time- and cost-effective risk assessment through modelling, insufficient data are available. Therefore, the authors examined uptake rates for three different AgNP sizes (20, 50 and 75 nm) and two tissue culture medium compositions (with and without foetal calf serum, FCS) under realistic exposure concentrations in pulmonary epithelial 16HBE14o-cells. The quantification of Ag in cells was carried out by high-resolution inductively coupled plasma mass spectrometry. We show for the first time that uptake kinetics of AgNPs into 16HBE14o-cells was highly influenced by medium composition. Uptake into cells was higher in medium without FCS, reaching approximately twice the concentration after 24 h than in medium supplemented with FCS, showing highest uptake for 50-nm AgNPs when expressed on a mass basis. This optimum shifts to 20 nm on a number basis, stressing the importance of the measurand in which results are presented. The importance of our research identifies that not just the uptake after a certain time point should be considered as dose but also the process of uptake (timing) might need to be considered when studying the mechanism of toxicity of nanoparticles.

  20. In-medium jet evolution: interplay between broadening and decoherence effects. The XXVth International Conference on Ultrarelativistic Nucleus-Nucleus Collisions

    NASA Astrophysics Data System (ADS)

    Apolinário, Liliana; Armesto, Néstor; Milhano, Guilherme; Salgado, Carlos A.

    2016-12-01

    The description of the modifications of the coherence pattern in a parton shower, in the presence of a QGP, has been actively addressed in recent studies. Among the several achievements, finite energy corrections, transverse momentum broadening due to medium interactions and interference effects between successive emissions have been extensively improved as they seem to be essential features for a correct description of the results obtained in heavy-ion collisions. In this work, based on the insights of our previous work [L. Apolinário, N. Armesto, J. G. Milhano, C. A. Salgado, Medium-induced gluon radiation and colour decoherence beyond the soft approximation, JHEP 1502 (2015) 119. arxiv:arXiv:1407.0599], we explore the physical interplay between broadening and decoherence, by generalising previous studies of medium-modifications of the antenna spectrum [Y. Mehtar-Tani, C. A. Salgado, K. Tywoniuk, Antiangular Ordering of Gluon Radiation in QCD Media, Phys. Rev. Lett. 106 (2011) 122002. arxiv:arXiv:1009.2965, J. Casalderrey-Solana, E. Iancu, Interference effects in medium-induced gluon radiation, JHEP 08 (2011) 015. arxiv:arXiv:1105.1760, Y. Mehtar-Tani, C. A. Salgado, K. Tywoniuk, The Radiation pattern of a QCD antenna in a dense medium, JHEP 10 (2012) 197. arxiv:arXiv:1205.5739] - so far restricted to the case where transverse motion is neglected. The result allow us to identify two quantities controlling the decoherence of a medium modified shower that can be used as building blocks for a successful future generation of jet quenching Monte Carlo simulators: a generalisation of the Δmed parameter of the works of [Y. Mehtar-Tani, C. A. Salgado, K. Tywoniuk, Antiangular Ordering of Gluon Radiation in QCD Media, Phys. Rev. Lett. 106 (2011) 122002. arxiv:arXiv:1009.2965, Y. Mehtar-Tani, C. A. Salgado, K. Tywoniuk, The Radiation pattern of a QCD antenna in a dense medium, JHEP 10 (2012) 197. arxiv:arXiv:1205.5739] - that controls the interplay between the transverse scale of the hard probe and the transverse resolution of the medium - and of the Δcoh in [L. Apolinário, N. Armesto, J. G. Milhano, C. A. Salgado, Medium-induced gluon radiation and colour decoherence beyond the soft approximation, JHEP 1502 (2015) 119. arxiv:arXiv:1407.0599] - that dictates the interferences between two emitters as a function of the transverse momentum broadening acquired by multiple scatterings with the medium.

  1. Implementation plan for Bolivian Mineral Exploration Fund

    USGS Publications Warehouse

    Kirkemo, Harold

    1978-01-01

    Bolivia ranks second among world producers of tin and antimony, and first in bismuth production. Mineral exports in 1975 were valued at $314.2 million, nearly 60 percent of the value of all exports, and petroleum product exports totalled nearly $157 million, or 30 percent of the total. Tin accounted for 58 percent of the total value of metallic mineral exports. The central government derived about 19 percent of its total tax revenues in 1975 from the mining sector. The mining sector consists of the large, medium, and small mining subsectors, a classification established by the government. Individual operations are referred to as large, medium, or small depending upon the subsector into which they are classified. All large mining enterprises are owned and operated by a government corporation, COMIBOL; the medium and small operations are privately owned. COMIBOL's exports in 1975 were valued at $171.8 million or 70 percent of the total mineral exports; the medium mines accounted for $55.5 million or 23 percent, and the small mines for $17.5 million or 7 percent of the total. The combination of high operating costs, low productivity, inadequate ore reserves, and insufficient risk capital for exploration and development has led to the realization that there is an urgent need to improve the situation for mining in Bolivia. Proposals are being studied to revise the tax code, a program is underway to evaluate selected mineral deposits for possible exploration and development, and programs are under consideration to encourage minerals exploration. A minerals exploration plan is proposed which would offer technical and financial aid to various segments in the minerals field. A program, estimated to cost between $2 million and $2.5 million annually, and to be operated by a new agency in the Ministry of Mining and Metallurgy, is outlined.

  2. Comparative proteomic analysis of fluoride treated rat bone provides new insights into the molecular mechanisms of fluoride toxicity.

    PubMed

    Wei, Yan; Zeng, Beibei; Zhang, Hua; Chen, Cheng; Wu, Yanli; Wang, Nanlan; Wu, Yanqiu; Zhao, Danqing; Zhao, Yuxi; Iqbal, Javed; Shen, Liming

    2018-07-01

    Long-term excessive intake of fluoride (F) could lead to chronic fluorosis. To explore the underlying molecular mechanisms, present study is designed to elucidate the effect of fluoride on proteome expression of bone in sodium fluoride (NaF)-treated SD rats. Hematoxylin and eosin (H&E) staining was used to determine the severity of osteofluorosis, and bone samples were submitted for iTRAQ analysis. The results showed that the cortical thickness and trabecular area of femur bone in medium- and high-dose groups were higher than in control group. Contrary to this, trabecular area was reduced in the low-dose group, indicating that the bone mass was increased in medium- and high-dose groups, and decreased in the low-dose group. Thirteen (13), 35, and 34 differentially expressed proteins were identified in low-, medium-, and high-dose group, respectively. The medium- and high-dose groups shared a more similar protein expression pattern. These proteins were mainly associated with collagen metabolism, proteoglycans (PGs), matrix metalloproteinases (MMPs), etc. The results suggested that the effect of NaF on SD rats is in a dose-dependent manner. Some key proteins found here may be involved in affecting the bone tissues and bone marrow or muscle, and account for the complex pathology and clinical symptoms of fluorosis. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Environmental potentials of policy instruments to mitigate nutrient emissions in Chinese livestock production.

    PubMed

    Zheng, Chaohui; Liu, Yi; Bluemling, Bettina; Mol, Arthur P J; Chen, Jining

    2015-01-01

    To minimize negative environmental impact of livestock production, policy-makers face a challenge to design and implement more effective policy instruments for livestock farmers at different scales. This research builds an assessment framework on the basis of an agent-based model, named ANEM, to explore nutrient mitigation potentials of five policy instruments, using pig production in Zhongjiang county, southwest China, as the empirical filling. The effects of different policy scenarios are simulated and compared using four indicators and differentiating between small, medium and large scale pig farms. Technology standards, biogas subsidies and information provisioning prove to be the most effective policies, while pollution fees and manure markets fail to environmentally improve manure management in pig livestock farming. Medium-scale farms are the more relevant scale category for a more environmentally sound development of Chinese livestock production. A number of policy recommendations are formulated as conclusion, as well as some limitations and prospects of the simulations are discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Sustained attention in adult ADHD: time-on-task effects of various measures of attention.

    PubMed

    Tucha, Lara; Fuermaier, Anselm B M; Koerts, Janneke; Buggenthin, Rieka; Aschenbrenner, Steffen; Weisbrod, Matthias; Thome, Johannes; Lange, Klaus W; Tucha, Oliver

    2017-02-01

    Neuropsychological research on adults with ADHD showed deficits in various aspects of attention. However, the majority of studies failed to explore the change of performance over time, so-called time-on-task effects. As a consequence, little is known about sustained attention performance of adults with ADHD. The aim of the present study was therefore to test the hypothesis of sustained attention deficits of adults with ADHD. Twenty-nine adults with ADHD and 30 healthy individuals were assessed on four 20-min tests of sustained attention, measuring alertness, selective attention, divided attention and flexibility. The deterioration of performance over time (time-on-task effects) was compared between patients with ADHD and healthy individuals to conclude on sustained attention performance. Compared to healthy individuals, patients with ADHD showed significant deficits of medium size in selective attention and divided attention. Furthermore, medium sustained attention deficits was observed in measures of alertness, selective attention and divided attention. This study supports the notion of sustained attention deficits of adults with ADHD.

  5. Universities, SMEs and Social Capital: Can You Get Too Much of a Good Thing? An Illustrative Analysis of One University's Knowledge Exchange Programme

    ERIC Educational Resources Information Center

    Gordon, Ian

    2016-01-01

    This article explores a university knowledge exchange programme for small and medium-sized enterprise (SME) owner-managers. Specifically, it considers why a programme designed to achieve growth in a group of SMEs through the creation of a network high in social capital may have become a constraint on the programme's effectiveness over a period of…

  6. Homogenization via the strong-permittivity-fluctuation theory with nonzero depolarization volume

    NASA Astrophysics Data System (ADS)

    Mackay, Tom G.

    2004-08-01

    The depolarization dyadic provides the scattering response of a single inclusion particle embedded within a homogenous background medium. These dyadics play a central role in formalisms used to estimate the effective constitutive parameters of homogenized composite mediums (HCMs). Conventionally, the inclusion particle is taken to be vanishingly small; this allows the pointwise singularity of the dyadic Green function associated with the background medium to be employed as the depolarization dyadic. A more accurate approach is pursued in this communication by taking into account the nonzero spatial extent of inclusion particles. Depolarization dyadics corresponding to inclusion particles of nonzero volume are incorporated within the strong-permittivity-fluctuation theory (SPFT). The linear dimensions of inclusion particles are assumed to be small relative to the electromagnetic wavelength(s) and the SPFT correlation length. The influence of the size of inclusion particles upon SPFT estimates of the HCM constitutive parameters is investigated for anisotropic dielectric HCMs.In particular, the interplay between correlation length and inclusion size is explored.

  7. [Regulative effects of hydrogen-rich medium on monocytic adhesion and vascular endothelial permeability].

    PubMed

    Wang, Wei-na; Xie, Ke-liang; Chen, Hong-guang; Han, Huan-zhi; Wang, Guo-lin; Yu, Yong-hao

    2013-11-19

    To explore the regulative effects of hydrogen-rich medium on lipopolysaccharide (LPS)-induced monocytes adhesion to human umbilical vein endothelial cells (HUVEC) and vascular endothelial permeability in vitro. Endothelial cells were seeded in 6-well plates and randomly divided into 4 groups (n = 42 each):control (A), hydrogen-rich medium (B), LPS (C) and LPS+hydrogen-rich medium (D). Cells were cultured in plain culture medium in groups A and C or in hydrogen-saturated culture medium in groups B and D.LPS 1 µg/ml was added into groups C and D.When forming a monolayer, monocytes were added into each group after 6, 12 and 24 h respectively. After a 90-minute co-culturing, adhesion status was detected by Wright-Giemsa stain.Supernatants were collected to detect the concentrations of vascular cell adhesion molecule-1 (VCAM-1) and E-selectin by enzyme-linked immunosorbent assay (ELISA). The expression of VE-cadherin was measured by Western blot. Cells were stained with immunofluorescence to show the distribution of VE-cadherin after a 24-hour incubation. Compared with group A, the adhesion of monocytes to endothelial cells increased (P < 0.05) in group C, the levels of E-selectin and VCAM-1 became elevated (P < 0.05) while the expression of VE-cadherin decreased significantly (P < 0.05). Compared with group C, adhesion decreased in group D (P < 0.05), the levels of E-selectin and VCAM-1 decreased (P < 0.05) while there was an increased expression of VE-cadherin (P < 0.05). Three timepoints showed the same tendency. The results of 24 h fluorescence indicated that, compared with group A, VE-cadherin was incomplete in cell-cell connections in group C.However it was complete and well-distributed in group D versus group C. Hydrogen-rich medium may reduce the LPS-induced release of adhesion molecules, lessen monocytic adhesion to HUVEC and regulate the expression of VE-cadherin to protect vascular permeability.

  8. Constraining in-medium nucleon-nucleon interactions via nucleus-nucleus reactions

    NASA Astrophysics Data System (ADS)

    Sammarruca, Francesca; White, Larz

    2010-11-01

    The nuclear equation of state is a broadly useful tool. Besides being the main input of stellar structure calculations, it allows a direct connection to the physics of nuclei. For instance, an energy functional (such as a mass formula), together with the energy/particle in nuclear matter, can be used to predict nuclear energies and radii [1]. The single-particle properties are also a key point to link infinite nuclear matter and actual nuclei. The parameters of the single-particle potential, in particular the effective mass, enter the calculations of, for instance, in-medium effective cross sections. From the well-known Glauber reaction theory, the total nucleus-nucleus reaction cross section is expressed in terms of the nuclear transparency, which, in turn, depends on the overlap of the nuclear density distributions and the elementary nucleon-nucleon (NN) cross sections. We explore the sensitivity of the reaction calculation to medium modifications of the NN cross sections to estimate the likelihood of constraining the latter through nuclear reactions. Ultimately, we wish to incorporate isospin asymmetry in the reaction model, having in mind connections with rare isotopes. [1] F. Sammarruca, arXiv:1002.00146 [nucl-th]; International Journal of Modern Physics, in press.

  9. Phase mismatched optical parametric generation in semiconductor magnetoplasma

    NASA Astrophysics Data System (ADS)

    Dubey, Swati; Ghosh, S.; Jain, Kamal

    2017-05-01

    Optical parametric generation involves the interaction of pump, signal, and idler waves satisfying law of conservation of energy. Phase mismatch parameter plays important role for the spatial distribution of the field along the medium. In this paper instead of exactly matching wave vector, a small mismatch is admitted with a degree of phase velocity mismatch between these waves. Hence the medium must possess certain finite coherence length. This wave mixing process is well explained by coupled mode theory and one dimensional hydrodynamic model. Based on this scheme, expressions for threshold pump field and transmitted intensity have been derived. It is observed that the threshold pump intensity and transmitted intensity can be manipulated by varying doping concentration and magnetic field under phase mismatched condition. A compound semiconductor crystal of n-InSb is assumed to be shined at 77 K by a 10.6μm CO2 laser with photon energy well below band gap energy of the crystal, so that only free charge carrier influence the optical properties of the medium for the I.R. parametric generation in a semiconductor plasma medium. Favorable parameters were explored to incite the said process keeping in mind the cost effectiveness and conversion efficiency of the process.

  10. Influence of embryo culture medium on incidence of ectopic pregnancy in in vitro fertilization.

    PubMed

    Lin, Shengli; Li, Rong; Zheng, Xiaoying; Chi, Hongbin; Ren, Xiulian; Yang, Rui; Liu, Ping; Qiao, Jie

    2015-12-01

    To explore the effect of type of media used to culture embryos for IVF on the incidence of ectopic pregnancy (EP). Retrospective analysis. University-affiliated IVF center. The retrospective analysis involved 23,481 women who underwent IVF-ET cycles between 2011 and 2013. None. There was an association between EP and the culture medium. During 23,481 fresh transfer cycles, 364 patients were diagnosed with EP. The EP to clinical pregnancy rate was 3.01% in the G5 group, 3.89% in the G5 Plus group, and 4.04% in the Global group. The EP to clinical pregnancy rates were significantly higher in the G5 Plus and Global groups than in the G5 group. After adjusting for confounding factors, the incidence of EP was significantly associated with the G5 Plus and Global media. Our results showed that there is an association between incidence of EP and the culture medium. The rates of EP to clinical pregnancy were significantly higher in the G5 Plus and Global media than in the G5 medium. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  11. Experimental investigation of the physical properties of medium and heavy oils, their vaporization and use in explosion engines. Part III

    NASA Technical Reports Server (NTRS)

    Heinlein, Fritz

    1926-01-01

    The test equipment for studying the vaporization of heavy and medium oils is described as well as some of the experimental properties explored such as vaporization speed and diffusion coefficient. The experiemtal arrangement is also discussed.

  12. Management Consulting and International Business Support for SMEs: Need and Obstacles

    ERIC Educational Resources Information Center

    Mughan, Terry; Lloyd-Reason, Lester; Zimmerman, Carsten

    2004-01-01

    This paper explores the challenges involved in the development of coordinated management consulting services for small and medium-sized international companies in the East of England. This paper synthesises the findings of recently published quantitative and qualitative research to identify the characteristics of small to medium-sized enterprises…

  13. Affordance of English-Medium Instruction Contexts in Taiwan

    ERIC Educational Resources Information Center

    Huang, Yi-Ping; Jhuang, Wun-Ting

    2015-01-01

    The proliferation of English-medium instruction (EMI) in nonnative English-speaking (NNES) contexts has compelled researchers to explore the challenges students face in such environments. Mostly quantitative in nature with foci on language-related difficulties in one type of institution or curriculum, these studies obscure the complexity of NNES…

  14. Texas Papers in Foreign Language Education, 1996.

    ERIC Educational Resources Information Center

    Texas Papers in Foreign Language Education, 1996

    1996-01-01

    Papers on foreign language education include: "The Message Is the Medium: Using Video Materials To Facilitate Foreign Language Performance" (Thomas J. Garza), which explores the use of this medium to enhance commonly-used non-communicative or text-bound teaching materials; "Product and Process Aspects of NES/EFL Students' Persuasive…

  15. Increasing efficiency of human mesenchymal stromal cell culture by optimization of microcarrier concentration and design of medium feed.

    PubMed

    Chen, Allen Kuan-Liang; Chew, Yi Kong; Tan, Hong Yu; Reuveny, Shaul; Weng Oh, Steve Kah

    2015-02-01

    Large amounts of human mesenchymal stromal cells (MSCs) are needed for clinical cellular therapy. In a previous publication, we described a microcarrier-based process for expansion of MSCs. The present study optimized this process by selecting suitable basal media, microcarrier concentration and feeding regime to achieve higher cell yields and more efficient medium utilization. MSCs were expanded in stirred cultures on Cytodex 3 microcarriers with media containing 10% fetal bovine serum. Process optimization was carried out in spinner flasks. A 2-L bioreactor with an automated feeding system was used to validate the optimized parameters explored in spinner flask cultures. Minimum essential medium-α-based medium supported faster MSC growth on microcarriers than did Dulbecco's modified Eagle's medium (doubling time, 31.6 ± 1.4 vs 42 ± 1.7 h) and shortened the process time. At microcarrier concentration of 8 mg/mL, a high cell concentration of 1.08 × 10(6) cells/mL with confluent cell concentration of 4.7 × 10(4)cells/cm(2) was achieved. Instead of 50% medium exchange every 2 days, we have designed a full medium feed that is based on glucose consumption rate. The optimal medium feed that consisted of 1.5 g/L glucose supported MSC growth to full confluency while achieving the low medium usage efficiency of 3.29 mL/10(6)cells. Finally, a controlled bioreactor with the optimized parameters achieved maximal confluent cell concentration with 16-fold expansion and a further improved medium usage efficiency of 1.68 mL/10(6)cells. We have optimized the microcarrier-based platform for expansion of MSCs that generated high cell yields in a more efficient and cost-effective manner. This study highlighted the critical parameters in the optimization of MSC production process. Copyright © 2015 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  16. Evaluation of the Effects of the Medium of Instruction on Science Learning of Hong Kong Secondary Students: Students' Self-Concept in Science

    ERIC Educational Resources Information Center

    Yip, Din Yan; Tsang, Wing Kwong

    2007-01-01

    A longitudinal study has been conducted to explore the impact of a new language policy for Hong Kong secondary schools on science learning. According to this policy, only schools that recruit the best 25% of students can teach science in English, the students' second language, while the other schools have to teach science in Chinese, the students'…

  17. Problem areas in the use of the firefly luciferase assay for bacterial detection

    NASA Technical Reports Server (NTRS)

    Picciolo, G. L.; Chappelle, E. W.; Knust, E. A.; Tuttle, S. A.; Curtis, C. A.

    1975-01-01

    By purifying the firefly luciferase extract and adding all necessary chemicals but ATP in excess, an assay for ATP was performed by measuring the amount of light produced when a sample containing soluble ATP is added to the luciferase reaction mixture. Instrumentation, applications, and basic characteristics of the luciferase assay are presented. Effect of the growth medium and length of time grown in this medium on ATP per viable E. coli values is shown in graphic form, along with an ATP concentration curve showing relative light units versus ATP injected. Reagent functions and concentration methods are explored. Efforts to develop a fast automatable system to detect the presence of bacteria in biological fluids, especially urine, resulted in the optimization of procedures for use with different types of samples.

  18. Analytical thermal model for end-pumped solid-state lasers

    NASA Astrophysics Data System (ADS)

    Cini, L.; Mackenzie, J. I.

    2017-12-01

    Fundamentally power-limited by thermal effects, the design challenge for end-pumped "bulk" solid-state lasers depends upon knowledge of the temperature gradients within the gain medium. We have developed analytical expressions that can be used to model the temperature distribution and thermal-lens power in end-pumped solid-state lasers. Enabled by the inclusion of a temperature-dependent thermal conductivity, applicable from cryogenic to elevated temperatures, typical pumping distributions are explored and the results compared with accepted models. Key insights are gained through these analytical expressions, such as the dependence of the peak temperature rise in function of the boundary thermal conductance to the heat sink. Our generalized expressions provide simple and time-efficient tools for parametric optimization of the heat distribution in the gain medium based upon the material and pumping constraints.

  19. Comparison of a Stratified Group Intervention (STarT Back) With Usual Group Care in Patients With Low Back Pain: A Nonrandomized Controlled Trial.

    PubMed

    Murphy, Susan E; Blake, Catherine; Power, Camillus K; Fullen, Brona M

    2016-04-01

    A nonrandomized controlled trial. This study aims to explore the effectiveness of group-based stratified care in primary care. Stratified care based on psychosocial screening (STarT Back) has demonstrated greater clinical and cost-effectiveness in patients with low back pain. However, low back pain interventions are often delivered in groups and evaluating this system of care in a group setting is important. Patients were recruited from 60 general practices and linked physiotherapy services. A new group stratified intervention was compared with a historical nonstratified control group. Patients stratified as low, medium and high risk were offered risk-matched group care. Consenting participants completed self-report measures of functional disability (primary outcome measure), pain, psychological distress, and beliefs. The historical control received a generic group intervention. Analysis was by intention to treat. In total, 251 patients in the new stratified intervention and 332 in the historical control were included in the primary analysis at 12 weeks. The mean age of patients was 43 ± 10.98 years. Overall adjusted mean changes in the RMDQ scores were higher in the stratified intervention than in the control arm at 12-week follow-up (P = 0.028). Exploring the risk groups, individually the high-risk stratified group, demonstrated better outcome over the controls (P = 0.031). The medium-risk stratified intervention demonstrated equally good outcomes (P = 0.125), and low-risk stratified patients, despite less intervention, did as well as the historical controls (P = 0.993). Stratified care delivered in a group setting demonstrated superior outcomes in the high-risk patients, and equally good outcomes for the medium and low-risk groups. This model, embedded in primary care, provides an early and effective model of chronic disease management and adds another dimension to the utility of the STarT Back system of care. 2.

  20. Accessing English and Networks at an English-Medium Multicultural Church in East Canada: An Ethnography

    ERIC Educational Resources Information Center

    Han, Huamei

    2014-01-01

    Drawing from a larger ethnography of skilled Chinese immigrants' language learning during settlement in Toronto, this article explores the role of informal interactions in facilitating immigrants learning English as a second language and settlement. Examining various activities and networks available at an English-medium multicultural church, this…

  1. Snow as Field-Teaching Medium for Earth Science.

    ERIC Educational Resources Information Center

    Custer, Stephan Gregory

    1991-01-01

    Snow is a widely available earth-science teaching medium which can be used to explore scientific concepts in the field, either directly or by analogy. Snow can be considered a mineral, sediment, sedimentary rock, or metamorphic rock. Natural processes such as crystal growth, melting, sedimentation, and metamorphism can be studied in practical time…

  2. Character Journaling through Social Networks: Exemplifying Tenets of the New Literacy Studies

    ERIC Educational Resources Information Center

    White, John Wesley; Hungerford-Kresser, Holly

    2014-01-01

    Countering reactionary attempts to ban social media from schools is a strong research based rationale for bringing social media into the literacy classroom. When used as a medium to explore literature--or more specifically for interactive character journaling--this medium exemplifies how meaning is created by individuals' interactions with…

  3. Feasibility of Adopting English-Medium Instruction at Iranian Universities

    ERIC Educational Resources Information Center

    Ghorbani, Mohammad Reza; Alavi, Sahar Zahed

    2014-01-01

    This study was an attempt to explore the potential possibilities of implementing English as the medium of instruction (EMI) at Iranian universities. The sequential exploratory mixed methods design was used to collect the perspectives of both students and content-area lecturers at the state University of Bojnord through e-mail interviews and survey…

  4. Workplace Health Promotion within Small and Medium-Sized Enterprises

    ERIC Educational Resources Information Center

    Moore, Ann; Parahoo, Kader; Fleming, Paul

    2010-01-01

    Purpose: The purpose of this study is to explore managers' understanding of workplace health promotion (WHP) and experiences of WHP activity within small and medium-sized enterprises (SMEs) in a Health and Social Care Trust area of Northern Ireland. The paper aims to focus on engagement with activities within the context of prevention of…

  5. Understanding Informal Learning in Small- and Medium-Sized Enterprises in South Korea

    ERIC Educational Resources Information Center

    Jeong, Shinhee; McLean, Gary N.; Park, Soyoun

    2018-01-01

    Purpose: This paper aims to explore informal learning experiences among employees working in South Korean small- and medium-sized enterprises (SMEs) with fewer than 100 employees. This study specifically seeks to understand the characteristics of informal learning in Korean SMEs and culturally sensitive contextual factors that shape informal…

  6. Self-Regulated Strategic Writing for Academic Studies in an English-Medium-Instruction Context

    ERIC Educational Resources Information Center

    Hu, Jingjing; Gao, Xuesong

    2018-01-01

    This study explored the processes of utilization of resources in secondary students' self-regulated strategic writing for academic studies in an English as medium of instruction context in Hong Kong. Drawing on multiple data sources collected through the observation of lessons, stimulated recall and semi-structured interviews, the study examined…

  7. No effect of embryo culture media on birthweight and length of newborns.

    PubMed

    Lin, Shengli; Li, Ming; Lian, Ying; Chen, Lixue; Liu, Ping

    2013-07-01

    Does the type of media used to culture embryos for IVF influence the birthweight and length of neonates? No significant differences were observed in birthweight and length among the three embryo culture media used for in vitro embryo culture. Since the establishment of IVF as an assisted reproductive technology (ART), many different culture systems have been used for the development of human embryos. Some studies have shown that the types of culture media influence the newborn birthweight; however, other studies have shown no effect. To further explore this contradictory issue, we compared the birthweight and length of neonates born after the transfer of embryos cultured in one of three commercially available media. This retrospective analysis of birthweight and length of newborns included 1201 women who delivered singletons and 445 women who delivered twins. The following three commercially available culture media were used: G5™, Global and Quinn's advantage media. Women who underwent IVF-ET cycles between 2008 and 2010 were analyzed. Patients younger than 40 years of age with a body mass index (BMI) <30 kg/m(2) were analyzed. Only data from singletons and twins born alive after the 20th week of gestation were included in the data analysis. Patients who received preimplantation genetic diagnosis (PGD) and donor oocytes were excluded. The analysis of 1201 singletons and 445 sets of twins showed no significant association between mean birthweight or mean birth length and the type of embryo culture medium. Inter-twin mean birthweight and length disparities were analyzed, but were not shown to be significantly different. Multiple linear regression analysis showed that maternal weight, maternal height, gestational age and infant gender were significantly related to birthweight, and paternal height, gestational age and newborn complications were significantly associated with birth length. The current study showed that birthweight and length of newborns were not associated with the embryo culture medium. More research needs to be performed to analyze the effects of other culture medium formulations and to evaluate the long-term effects of embryo culture medium on the health of children conceived through ART. WIDER IMPLICATIONS OF THESE FINDINGS: Our retrospective study suggests that embryo culture medium does not influence neonatal birthweight and length; however, the effects of culture medium on epigenetic variation of embryos need to be studied further.

  8. Effects of culture medium compositions on antidiabetic activity and anticancer activity of marine endophitic bacteria isolated from sponge

    NASA Astrophysics Data System (ADS)

    Maryani, Faiza; Mulyani, Hani; Artanti, Nina; Udin, Linar Zalinar; Dewi, Rizna Triana; Hanafi, Muhammad; Murniasih, Tutik

    2017-01-01

    High diversity of Indonesia marine spesies and their ability in producing secondary metabolite that can be used as a drug candidate cause this fascinating topic need to explore. Most of marine organisms explored to discover drug is macroorganism whereas microorganism (such as Indonesia marine bacteria) is very limited. Therefore, in this report, antidiabetic and anticancer activity of Indonesia marine bacteria isolated from Sponges's extract have been studied. Bacteria strain 8.9 which are collection of Research Center for Oseanography, Indonesian Institute of Sciences were from Barrang Lompo Island, Makasar, Indonesia. Bacteria were cultured in different culture medium compositions (such as: different pH, source of glucose and water) for 48 hours on a shaker, then they were extracted with ethyl asetate. Extracts of bacteria were tested by DPPH method (antioxidant activity), alpha glucosidase inhibitory activity method (antidiabetic activity), and Alamar Blue assay (anticancer activity) at 200 ppm. According to result, extract of bacteria in pH 8.0 exhibited the greatest antioxidant (19.27% inhibition), antidiabetic (63.95% inhibition) and anticancer activity of T47D cell line (44.62% cell viability) compared to other extracts. However, effect of addition of sugar sources (such as: glucose, sucrose, and soluble starch) and effect of addition of water/sea water exhibited less influence on their bioactivities. In conclusion, Indonesia marine bacteria isolated from sponge have potential a source of bioactive compound in drug discovery field.

  9. [Effects of Frankincense and Myrrh essential oil on transdermal absorption of ferulic acid in Chuanxiong].

    PubMed

    Guan, Yong-Mei; Tao, Ling; Zhu, Xiao-Fang; Zang, Zhen-Zhong; Jin, Chen; Chen, Li-Hua

    2017-09-01

    The aim of this paper was to explore the effects of Frankincense and Myrrh essential oil on transdermal absorption, and investigate the mechanism of permeation on the microstructure and molecular structure of stratum corneum. Through the determination of stratum corneum/medium partition coefficient of ferulicacid in Chuanxiong influenced by Frankincense and Myrrh essential oil, the effects of volatile oil of frankincense and Myrrh on the the microscopic and molecular structure of stratum corneum were explored by observation of skin stratum corneum structure under scanning electron microscopy, and investigation of frankincense and myrrh essential oil effects on the molecular structure of keratin and lipids in stratum corneum under Fourier transform infrared spectroscopy. The results showed that the oil could enhance the distribution of ferulic acid in the stratum corneum and medium, and to a certain extent damaged the imbricate structure of stratum corneum which was originally regularly, neatly, and closely arranged; some epidermal scales turned upward, with local peeling phenomenon. In addition, frankincense and myrrh essential oil caused the relative displacement of CH2 stretching vibration peak of stratum corneum lipids and amide stretching vibration peak of stratum corneum keratin, indicating that frankincense and myrrh essential oil may change the conformation of lipid and keratin in the stratum corneum, increase the bilayer liquidity of the stratum corneum lipid, and change the orderly and compact structure to increase the skin permeability and reduce the effect of barrier function. It can be concluded that Frankincense and Myrrh essential oil can promote the permeation effect by increasing the distribution of drugs in the stratum corneum and changing the structure of the stratum corneum. Copyright© by the Chinese Pharmaceutical Association.

  10. A Titan Explorer Mission Utilizing Solar Electric Propulsion and Chemical Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Cupples, Michael; Coverstone, Vicki

    2003-01-01

    Mission and Systems analyses were performed for a Titan Explorer Mission scenario utilizing medium class launch vehicles, solar electric propulsion system (SEPS) for primary interplanetary propulsion, and chemical propulsion for capture at Titan. An examination of a range of system factors was performed to determine their affect on the payload delivery capability to Titan. The effect of varying the launch vehicle, solar array power, associated number of SEPS thrusters, chemical propellant combinations, tank liner thickness, and tank composite overwrap stress factor was investigated. This paper provides a parametric survey of the aforementioned set of system factors, delineating their affect on Titan payload delivery, as well as discussing aspects of planetary capture methodology.

  11. An evaluation of the suitability of ERTS data for the purposes of petroleum exploration. [Anadarko Basin of Texas and Oklahoma

    NASA Technical Reports Server (NTRS)

    Collins, R. J.; Mccown, F. P.; Stonis, L. P.; Petzel, G.; Everett, J. R.

    1974-01-01

    This experiment was designed to determine the types and amounts of information valuable to petroleum exploration extractable from ERTS data and the cost of obtaining the information using traditional or conventional means. It was desired that an evaluation of this new petroleum exploration tool be made in a geologically well known area in order to assess its usefulness in an unknown area. The Anadarko Basin lies in western Oklahoma and the panhandle of Texas. It was chosen as a test site because there is a great deal of published information available on the surface and subsurface geology of the area, and there are many known structures that act as traps for hydrocarbons. This basin is similar to several other large epicontinental sedimentary basins. It was found that ERTS imagery is an excellent tool for reconnaissance exploration of large sedimentary basins or new exploration provinces. For the first time, small and medium size oil companies can rapidly and effectively analyze exploration provinces as a whole.

  12. Plasma Induced Degradation of Benzidine in Aqueous Solution

    NASA Astrophysics Data System (ADS)

    Gao, Jinzhang; Gai, Ke; Yang, Wu; Dong, Yanjie

    2003-10-01

    The degradation of benzidine in aqueous solution by the low temperature plasma was examined. The results showed that the concentration of medium and the value of pH have an appreciable effect on the degradation of benzidine. What is more important is that iron ions acting as a catalyst play an important role in this reaction. For exploring the degradation mechanism of benzidine, some of the intermediate products were recorded by HPLC (high performance liquid chromatography).

  13. Light clusters in nuclear matter: Excluded volume versus quantum many-body approaches

    NASA Astrophysics Data System (ADS)

    Hempel, Matthias; Schaffner-Bielich, Jürgen; Typel, Stefan; Röpke, Gerd

    2011-11-01

    The formation of clusters in nuclear matter is investigated, which occurs, e.g., in low-energy heavy-ion collisions or core-collapse supernovae. In astrophysical applications, the excluded volume concept is commonly used for the description of light clusters. Here we compare a phenomenological excluded volume approach to two quantum many-body models, the quantum statistical model and the generalized relativistic mean-field model. All three models contain bound states of nuclei with mass number A≤4. It is explored to which extent the complex medium effects can be mimicked by the simpler excluded volume model, regarding the chemical composition and thermodynamic variables. Furthermore, the role of heavy nuclei and excited states is investigated by use of the excluded volume model. At temperatures of a few MeV the excluded volume model gives a poor description of the medium effects on the light clusters, but there the composition is actually dominated by heavy nuclei. At larger temperatures there is a rather good agreement, whereas some smaller differences and model dependencies remain.

  14. Synthetic cystic fibrosis sputum medium diminishes Burkholderia cenocepacia antifungal activity against Aspergillus fumigatus independently of phenylacetic acid production.

    PubMed

    Lightly, Tasia Joy; Phung, Ryan R; Sorensen, John L; Cardona, Silvia T

    2017-05-01

    Phenylacetic acid (PAA), an intermediate of phenylalanine degradation, is emerging as a signal molecule in microbial interactions with the host. In this work, we explore the presence of phenylalanine and PAA catabolism in 3 microbial pathogens of the cystic fibrosis (CF) lung microbiome: Pseudomonas aeruginosa, Burkholderia cenocepacia, and Aspergillus fumigatus. While in silico analysis of B. cenocepacia J2315 and A. fumigatus Af293 genome sequences showed complete pathways from phenylalanine to PAA, the P. aeruginosa PAO1 genome lacked several coding genes for phenylalanine and PAA catabolic enzymes. High-performance liquid chromatography analysis of supernatants from B. cenocepacia K56-2 detected PAA when grown in Luria-Bertani medium but not in synthetic cystic fibrosis sputum medium (SCFM). However, we were unable to identify PAA production by A. fumigatus or P. aeruginosa in any of the conditions tested. The inhibitory effect of B. cenocepacia on A. fumigatus growth was evaluated using agar plate interaction assays. Inhibition of fungal growth by B. cenocepacia was lessened in SCFM but this effect was not dependent on bacterial production of PAA. In summary, while we demonstrated PAA production by B. cenocepacia, we were not able to link this metabolite with the B. cenocepacia - A. fumigatus microbial interaction in CF nutritional conditions.

  15. A comparison of workplace safety perceptions among financial decision-makers of medium- vs. large-size companies.

    PubMed

    Huang, Yueng-Hsiang; Leamon, Tom B; Courtney, Theodore K; Chen, Peter Y; DeArmond, Sarah

    2011-01-01

    This study, through a random national survey in the U.S., explored how corporate financial decision-makers perceive important workplace safety issues as a function of the size of the company for which they worked (medium- vs. large-size companies). Telephone surveys were conducted with 404 U.S. corporate financial decision-makers: 203 from medium-size companies and 201 from large companies. Results showed that the patterns of responding for participants from medium- and large-size companies were somewhat similar. The top-rated safety priorities in resource allocation reported by participants from both groups were overexertion, repetitive motion, and bodily reaction. They believed that there were direct and indirect costs associated with workplace injuries and for every dollar spent improving workplace safety, more than four dollars would be returned. They perceived the top benefits of an effective safety program to be predominately financial in nature - increased productivity and reduced costs - and the safety modification participants mentioned most often was to have more/better safety-focused training. However, more participants from large- than medium-size companies reported that "falling on the same level" was the major cause of workers' compensation loss, which is in line with industry loss data. Participants from large companies were more likely to see their safety programs as better than those of other companies in their industries, and those of medium-size companies were more likely to mention that there were no improvements needed for their companies. Copyright © 2009 Elsevier Ltd. All rights reserved.

  16. Mobile Language Learning: The Medium Is ^Not The Message

    ERIC Educational Resources Information Center

    Lotherington, Heather

    2018-01-01

    This paper repositions McLuhan's (1964/1965) extension theory of technology in the context of "mobile (-assisted) language learning" (MALL), and explores whether and how the medium (i.e., the mobile device) impacts the message (i.e., the target language) and the means by which it is taught in MALL. A survey of recommended commercial MALL…

  17. Small and Medium-Sized Information Technology Firms: Assessment of Non-Local Partnership Facilitators

    ERIC Educational Resources Information Center

    Findikoglu, Melike Nur

    2012-01-01

    A two-phased qualitative study was conducted to explore the facilitators of non-local (i.e. domestic or international) partnerships formed by small- and medium-sized firms (SME). Rooted in trust, proximity and dynamic capabilities lenses, the study focused on behaviors of SMEs performing in dynamic, competitive and highly interlinked industry, the…

  18. Exploring the Potential for Language Supportive Learning in English Medium Instruction: A Rwandan Case Study

    ERIC Educational Resources Information Center

    Milligan, Lizzi O.; Clegg, John; Tikly, Leon

    2016-01-01

    This article puts forward the argument for language supportive learning for learners in English medium instruction (EMI) classrooms based on the findings from a mixed methods study in Rwanda. The article first reviews the relevant literature and research which looks at the concept of language support, focusing on textbooks and pedagogy in…

  19. Exploring the Use of Internet by University Students for Seeking Health Related Information

    ERIC Educational Resources Information Center

    Ahmad, Asad; Khan, Mohammed Naved; Rahman, Obaidur

    2017-01-01

    Purpose: Internet is both a medium and a platform for information exchange. This characteristic of internet is gradually metamorphosing it into an e-learning enabler. A significant percentage of internet users access health-related information through the medium of internet, but little is known about the factors that determine such behaviour. This…

  20. The Forgotten Voices in Higher Education: Students' Satisfaction with English-Medium Instruction

    ERIC Educational Resources Information Center

    Karakas, Ali

    2017-01-01

    This study explores how satisfied Turkish students are with English-medium instruction (EMI) in the context of higher education in an era when EMI universities operate as international brands capitalizing on English as a commodity to vie for more customers, that is, national and international students. Data were collected through a questionnaire…

  1. In a Different Voice: Promises and Trials of Non-English Medium Journals

    ERIC Educational Resources Information Center

    Lee, Yew-Jin

    2015-01-01

    Various issues confronting science education publications that cater for non-English speaking audiences are explored. With reference to an English-medium journal that the author co-edits, two main conundrums are discussed: (1) How to serve local school practitioners in concrete ways while fulfilling the institutional goals of academia, and (2) the…

  2. Optimization of contrast resolution by genetic algorithm in ultrasound tissue harmonic imaging.

    PubMed

    Ménigot, Sébastien; Girault, Jean-Marc

    2016-09-01

    The development of ultrasound imaging techniques such as pulse inversion has improved tissue harmonic imaging. Nevertheless, no recommendation has been made to date for the design of the waveform transmitted through the medium being explored. Our aim was therefore to find automatically the optimal "imaging" wave which maximized the contrast resolution without a priori information. To overcome assumption regarding the waveform, a genetic algorithm investigated the medium thanks to the transmission of stochastic "explorer" waves. Moreover, these stochastic signals could be constrained by the type of generator available (bipolar or arbitrary). To implement it, we changed the current pulse inversion imaging system by including feedback. Thus the method optimized the contrast resolution by adaptively selecting the samples of the excitation. In simulation, we benchmarked the contrast effectiveness of the best found transmitted stochastic commands and the usual fixed-frequency command. The optimization method converged quickly after around 300 iterations in the same optimal area. These results were confirmed experimentally. In the experimental case, the contrast resolution measured on a radiofrequency line could be improved by 6% with a bipolar generator and it could still increase by 15% with an arbitrary waveform generator. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Exploring Racism through Photography

    ERIC Educational Resources Information Center

    Fey, Cass; Shin, Ryan; Cinquemani, Shana; Marino, Catherine

    2010-01-01

    Photography is a powerful medium with which to explore social issues and concerns through the intersection of artistic form and concept. Through the discussions of images and suggested activities, students will understand various ways photographers have documented and addressed racism and discrimination. This Instructional Resource presents a…

  4. A passive satellite deorbiting strategy for medium earth orbit using solar radiation pressure and the J2 effect

    NASA Astrophysics Data System (ADS)

    Lücking, Charlotte; Colombo, Camilla; McInnes, Colin R.

    2012-08-01

    The growing population of space debris poses a serious risk to the future of space flight. To effectively manage the increase of debris in orbit, end-of life disposal has become a key requirement for future missions. This poses a challenge for Medium Earth Orbit (MEO) spacecraft which require a large Δv to re-enter the atmosphere or reach the geostationary graveyard orbit. This paper further explores a passive strategy based on the joint effects of solar radiation pressure and the Earth's oblateness acting on a high area-to-mass-ratio object. The concept was previously presented as an analytical planar model. This paper uses a full 3D model to validate the analytical results numerically for equatorial circular orbits first, then investigating higher inclinations. It is shown that for higher inclinations the initial position of the Sun and right ascension of the ascending node become increasingly important. A region of very low required area-to-mass-ratio is identified in the parameter space of semi-major axis and inclination which occurs for altitudes below 10,000 km.

  5. Medium-energy particle experiments—electron analyzer (MEP-e) for the exploration of energization and radiation in geospace (ERG) mission

    NASA Astrophysics Data System (ADS)

    Kasahara, Satoshi; Yokota, Shoichiro; Mitani, Takefumi; Asamura, Kazushi; Hirahara, Masafumi; Shibano, Yasuko; Takashima, Takeshi

    2018-05-01

    The medium-energy particle experiments—electron analyzer onboard the exploration of energization and radiation in geospace spacecraft measures the energy and direction of each incoming electron in the energy range of 7-87 keV. The sensor covers a 2 π-radian disklike field of view with 16 detectors, and the full solid angle coverage is achieved through the spacecraft's spin motion. The electron energy is independently measured by both an electrostatic analyzer and avalanche photodiodes, enabling significant background reduction. We describe the technical approach, data output, and examples of initial observations.[Figure not available: see fulltext.

  6. The Interstellar Heliopause Probe: Heliospheric Boundary Explorer Mission to the Interstellar Medium

    NASA Astrophysics Data System (ADS)

    Wimmer-Schweingruber, Robert F.; McNutt, Ralph

    2009-04-01

    The Sun, driving a supersonic solar wind, cuts out of the local interstellar medium a giant plasma bubble, the heliosphere. ESA, jointly with NASA, has had an important role in the development of our current understanding of the Suns’ immediate neighborhood. Ulysses is the only spacecraft exploring the third, out-of-ecliptic dimension, while SOHO has allowed us to better understand the influence of the Sun and to image the glow of interstellar matter in the heliosphere. Voyager 1 has recently encountered the innermost boundary of this plasma bubble, the termination shock, and is returning exciting yet puzzling data of this remote region. The next logical step is to leave the heliosphere and to thereby map out in unprecedented detail the structure of the outer heliosphere and its boundaries, the termination shock, the heliosheath, the heliopause, and, after leaving the heliosphere, to discover the true nature of the hydrogen wall, the bow shock, and the local interstellar medium beyond. This will greatly advance our understanding of the heliosphere that is the best-known example for astrospheres as found around other stars. Thus, IHP/HEX will allow us to discover, explore, and understand fundamental astrophysical processes in the largest accessible plasma laboratory, the heliosphere.

  7. Use of spent mushroom substrate for production of Bacillus thuringiensis by solid-state fermentation.

    PubMed

    Wu, Songqing; Lan, Yanjiao; Huang, Dongmei; Peng, Yan; Huang, Zhipeng; Xu, Lei; Gelbic, Ivan; Carballar-Lejarazu, Rebeca; Guan, Xiong; Zhang, Lingling; Zou, Shuangquan

    2014-02-01

    The aim of this study was to explore a cost-effective method for the mass production of Bacillus thuringiensis (Bt) by solid-state fermentation. As a locally available agroindustrial byproduct, spent mushroom substrate (SMS) was used as raw material for Bt cultivation, and four combinations of SMS-based media were designed. Fermentation conditions were optimized on the best medium and the optimal conditions were determined as follows: temperature 32 degrees C, initial pH value 6, moisture content 50%, the ratio of sieved material to initial material 1:3, and inoculum volume 0.5 ml. Large scale production of B. thuringiensis subsp. israelensis (Bti) LLP29 was conducted on the optimal medium at optimal conditions. High toxicity (1,487 international toxic units/milligram) and long larvicidal persistence of the product were observed in the study, which illustrated that SMS-based solid-state fermentation medium was efficient and economical for large scale industrial production of Bt-based biopesticides. The cost of production of 1 kg of Bt was approximately US$0.075.

  8. How to share underground reservoirs

    NASA Astrophysics Data System (ADS)

    Schrenk, K. J.; Araújo, N. A. M.; Herrmann, H. J.

    2012-10-01

    Many resources, such as oil, gas, or water, are extracted from porous soils and their exploration is often shared among different companies or nations. We show that the effective shares can be obtained by invading the porous medium simultaneously with various fluids. Partitioning a volume in two parts requires one division surface while the simultaneous boundary between three parts consists of lines. We identify and characterize these lines, showing that they form a fractal set consisting of a single thread spanning the medium and a surrounding cloud of loops. While the spanning thread has fractal dimension 1.55 +/- 0.03, the set of all lines has dimension 1.69 +/- 0.02. The size distribution of the loops follows a power law and the evolution of the set of lines exhibits a tricritical point described by a crossover with a negative dimension at criticality.

  9. Analysis of Managing Safety in Small Enterprises: Dual-Effects of Employee Prosocial Safety Behavior and Government Inspection

    PubMed Central

    2018-01-01

    This paper aims to promote a national and international occupational health and safety (OHS) intervention for small and medium enterprises (SMEs) within internal and external resources. Based on the characteristics of small SME management, the work environment and occupational health may be positively affected by the dual-effects of employees and government. Evolutionary game theory is utilized to identify relevant interactions among the government, small enterprises, and employees. Furthermore, dynamic simulations of the evolutionary game model are used to explore stability strategies and to identify modes of equilibrium. PMID:29707574

  10. Effects of atmospheric variations on acoustic system performance

    NASA Technical Reports Server (NTRS)

    Nation, Robert; Lang, Stephen; Olsen, Robert; Chintawongvanich, Prasan

    1993-01-01

    Acoustic propagation over medium to long ranges in the atmosphere is subject to many complex, interacting effects. Of particular interest at this point is modeling low frequency (less than 500 Hz) propagation for the purpose of predicting ranges and bearing accuracies at which acoustic sources can be detected. A simple means of estimating how much of the received signal power propagated directly from the source to the receiver and how much was received by turbulent scattering was developed. The correlations between the propagation mechanism and detection thresholds, beamformer bearing estimation accuracies, and beamformer processing gain of passive acoustic signal detection systems were explored.

  11. Method and apparatus for subsurface exploration

    NASA Technical Reports Server (NTRS)

    Wilcox, Brian (Inventor)

    2002-01-01

    A subsurface explorer (SSX) for exploring beneath the terrestrial surface of planetary bodies such as the Earth, Mars, or comets. This exploration activity utilizes appropriate sensors and instrument to evaluate the composition, structure, mineralogy and possibly biology of the subsurface medium, as well as perhaps the ability to return samples of that medium back to the surface. The vehicle comprises an elongated skin or body having a front end and a rear end, with a nose piece at the front end for imparting force to composition material of the planetary body. Force is provided by a hammer mechanism to the back side of a nose piece from within the body of the vehicle. In the preferred embodiment, a motor spins an intermediate shaft having two non-uniform threads along with a hammer which engages these threads with two conical rollers. A brake assembly halts the rotation of the intermediate shaft, causing the conical roller to spin down the non-uniform thread to rapidly and efficiently convert the rotational kinetic energy of the hammer into translational energy.

  12. Mechanisms for the target patterns formation in a stochastic bistable excitable medium

    NASA Astrophysics Data System (ADS)

    Verisokin, Andrey Yu.; Verveyko, Darya V.; Postnov, Dmitry E.

    2018-04-01

    We study the features of formation and evolution of spatiotemporal chaotic regime generated by autonomous pacemakers in excitable deterministic and stochastic bistable active media using the example of the FitzHugh - Nagumo biological neuron model under discrete medium conditions. The following possible mechanisms for the formation of autonomous pacemakers have been studied: 1) a temporal external force applied to a small region of the medium, 2) geometry of the solution region (the medium contains regions with Dirichlet or Neumann boundaries). In our work we explore the conditions for the emergence of pacemakers inducing target patterns in a stochastic bistable excitable system and propose the algorithm for their analysis.

  13. The Gum Nebula and Related Problems

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Proceedings of a symposium concerning the Gum Nebula (GN) and related topics are reported. Papers presented include: Colin Gum and the discovery of the GN; identification of the GN as the fossil Stromgren sphere of Vela X Supernova; size and shape of GN; formation of giant H-2 regions following supernova explosions; radio astronomy Explorer 1 observations of GN; cosmic ray effects in the GN; low intensity H beta emission from the interstellar medium; and how to recognize and analyze GN. Astronomical charts and diagrams are included.

  14. Interactive Video Gaming compared to Health Education in Older Adults with MCI: A Feasibility Study

    PubMed Central

    Hughes, Tiffany F.; Flatt, Jason D.; Fu, Bo; Butters, Meryl A.; Chang, Chung-Chou H.; Ganguli, Mary

    2014-01-01

    Objective We evaluated the feasibility of a trial of Wii interactive video gaming, and its potential efficacy at improving cognitive functioning compared to health education, in a community sample of older adults with neuropsychologically defined mild cognitive impairment (MCI). Methods Twenty older adults were equally randomized to either group-based interactive video gaming or health education for 90 minutes each week for 24 weeks. Although the primary outcomes were related to study feasibility, we also explored the effect of the intervention on neuropsychological performance and other secondary outcomes. Results All 20 participants completed the intervention, and 18 attended at least 80% of the sessions. The majority (80%) of participants were “very much” satisfied with the intervention. Bowling was enjoyed by the most participants, and was also the rated highest among the games for mental, social and physical stimulation. We observed medium effect sizes for cognitive and physical functioning in favor of the interactive video gaming condition, but these effects were not statistically significant in this small sample. Conclusion Interactive video gaming is feasible for older adults with MCI and medium effects sizes in favor of the Wii group warrant a larger efficacy trial. PMID:24452845

  15. The Safety and Efficacy of Irreversible Electroporation for Large Hepatocellular Carcinoma.

    PubMed

    Zeng, Jianying; Liu, Guifeng; Li, Zhong-Hai; Yang, Yi; Fang, Gang; Li, Rong-Rong; Xu, Ke-Cheng; Niu, Lizhi

    2017-02-01

    This study aimed to investigate the safety and effectiveness of irreversible electroporation ablation for unresectable large liver cancer. Fourteen patients were enrolled: 8 with large hepatocellular carcinoma (tumor diameter: 5.1-11.5 cm) and 6 with medium hepatocellular carcinoma (tumor diameter: 3.0-4.1 cm). All patients received percutaneous irreversible electroporation ablation. Ablation time and the incidence of complications were assessed by a t test. Post-irreversible electroporation and regular contrast-enhanced computerized tomography scans were performed to investigate the effect of tumor size (large vs medium) on irreversible electroporation treatment efficacy; 4-table data were assessed using a Fisher exact test. The 14 patients completed irreversible electroporation ablation successfully. In the large hepatocellular carcinoma group, no major complications occurred in the perioperative period. Minor complications comprised bloating, hypokalemia, edema, low white blood cells, and blood clotting abnormalities. All complications were mild and improved after symptomatic treatment. The frequency of minor complications was not significantly different ( P > .05) compared with the medium hepatocellular carcinoma group. The average follow-up time was 2.8 ± 2.1 months and complete ablation was achieved in 25% (2/8; residual = 75%). For the patients with medium hepatocellular carcinoma, the mean follow-up time was 4.3 ± 3.2 months; the rate of complete ablation was 66.6% (4/6; residual rate = 33.3%). The complete ablation rate was not statistically different between the 2 groups ( P > .05). Irreversible electroporation ablation for unresectable large hepatocellular carcinoma is safe, with no major complications. Short-term efficacy is relatively good; however, long-term efficacy remains to be explored.

  16. Applying the Flipped Learning Model to an English-Medium Nursing Course.

    PubMed

    Choi, Heeseung; Kim, Jeongeun; Bang, Kyung Sook; Park, Yeon Hwan; Lee, Nam Ju; Kim, Chanhee

    2015-12-01

    An emerging trend in Asian higher education is English-medium instruction (EMI), which uses English as the primary instructional language. EMI prepares domestic students for international leadership; however, students report difficulty in learning, and educators have raised questions concerning the effectiveness of EMI. The flipped learning model (FLM), in which lecture and homework activities for a course are reversed, was applied to an English-medium course offered by a college of nursing in Korea. The aims of this study were to: 1) revise an existing English-medium nursing course using the FLM; 2) explore students' learning experiences and their acceptance of the FLM; and 3) identify key factors in the success of FLM. We used a descriptive, cross-sectional, mixed-methods design and the participants were students at one nursing school in Korea. A series of course development meetings with faculties from the nursing school and the center for teaching and learning were used to develop the course format and content. We conducted course evaluations using the Flipped Course Evaluation Questionnaire with open-ended questions and focus group interviews. Students (N=75) in a 15-week nursing course responded to a survey after completing the course. Among them, seven students participated in one of two focus groups. Overall, students accepted and favored the flipped learning strategy, and indicated that the method enhanced lecture content and their understanding of it. Factors associated with effective instruction included structured monitoring systems and motivational environments. The FLM requires sufficient preparation to facilitate student motivation and maximize learning outcomes.

  17. The Effects of Medium Spiny Neuron Morphologcial Changes on Basal Ganglia Network under External Electric Field: A Computational Modeling Study.

    PubMed

    Zhang, Xiaohan; Liu, Shenquan; Zhan, Feibiao; Wang, Jing; Jiang, Xiaofang

    2017-01-01

    The damage of dopaminergic neurons that innervate the striatum has been considered to be the proximate cause of Parkinson's disease (PD). In the dopamine-denervated state, the loss of dendritic spines and the decrease of dendritic length may prevent medium spiny neuron (MSN) from receiving too much excitatory stimuli from the cortex, thereby reducing the symptom of Parkinson's disease. However, the reduction in dendritic spine density obtained by different experiments is significantly different. We developed a biological-based network computational model to quantify the effect of dendritic spine loss and dendrites tree degeneration on basal ganglia (BG) signal regulation. Through the introduction of error index (EI), which was used to measure the attenuation of the signal, we explored the amount of dendritic spine loss and dendritic trees degradation required to restore the normal regulatory function of the network, and found that there were two ranges of dendritic spine loss that could reduce EI to normal levels in the case of dopamine at a certain level, this was also true for dendritic trees. However, although these effects were the same, the mechanisms of these two cases were significant difference. Using the method of phase diagram analysis, we gained insight into the mechanism of signal degradation. Furthermore, we explored the role of cortex in MSN morphology changes dopamine depletion-induced and found that proper adjustments to cortical activity do stop the loss in dendritic spines induced by dopamine depleted. These results suggested that modifying cortical drive onto MSN might provide a new idea on clinical therapeutic strategies for Parkinson's disease.

  18. [Effectiveness of education based on neuroscience in the treatment of musculoskeletal chronic pain].

    PubMed

    Cuenda-Gago, J D; Espejo-Antunez, L

    2017-07-01

    Chronic pain is one of the most frequent health, economic and social problems. Given this, numerous approaches have been described, one of which is pain neuroscience education. To examine the effectiveness of pain neuroscience education in the treatment of musculoskeletal disorders with chronic pain and to explore the impact of specific aspects of the technique on its effectiveness. Relevant studies published between 2000 and 2015 were identified by searching PubMed, Scopus and Web of Science. Studies identified by electronic searches were screened against a set of pre-defined inclusion criteria. PEDro and SIGN scales were used to evaluate the methodological quality of the included studies. Ten studies were included in this systematic review. The main outcomes that were measured were pain, disability, neurophysiology pain test, attitudes and beliefs, fear-avoidance beliefs, self-care, kinesiophobia, quality of life and algometry. The results suggest that pain neuroscience education is effective in the short term and medium/long term for pain relief, either alone or combined with multimodal treatment. It was also effective in normalizing cognitions about pain, fear-avoidance beliefs, and self-care. Despite some evidence for a positive effect in the short and medium/long term, the heterogeneity in the technical aspects used does not allow the obtaining of conclusive results.

  19. XIPE: the x-ray imaging polarimetry explorer

    NASA Astrophysics Data System (ADS)

    Soffitta, P.; Bellazzini, R.; Bozzo, E.; Burwitz, V.; Castro-Tirado, A.; Costa, E.; Courvoisier, T.; Feng, H.; Gburek, S.; Goosmann, R.; Karas, V.; Matt, G.; Muleri, F.; Nandra, K.; Pearce, M.; Poutanen, J.; Reglero, V.; Sabau Maria, D.; Santangelo, A.; Tagliaferri, G.; Tenzer, C.; Vink, J.; Weisskopf, M. C.; Zane, S.; Agudo, I.; Antonelli, A.; Attina, P.; Baldini, L.; Bykov, A.; Carpentiero, R.; Cavazzuti, E.; Churazov, E.; Del Monte, E.; De Martino, D.; Donnarumma, I.; Doroshenko, V.; Evangelista, Y.; Ferreira, I.; Gallo, E.; Grosso, N.; Kaaret, P.; Kuulkers, E.; Laranaga, J.; Latronico, L.; Lumb, D. H.; Macian, J.; Malzac, J.; Marin, F.; Massaro, E.; Minuti, M.; Mundell, C.; Ness, J. U.; Oosterbroek, T.; Paltani, S.; Pareschi, G.; Perna, R.; Petrucci, P.-O.; Pinazo, H. B.; Pinchera, M.; Rodriguez, J. P.; Roncadelli, M.; Santovincenzo, A.; Sazonov, S.; Sgro, C.; Spiga, D.; Svoboda, J.; Theobald, C.; Theodorou, T.; Turolla, R.; Wilhelmi de Ona, E.; Winter, B.; Akbar, A. M.; Allan, H.; Aloisio, R.; Altamirano, D.; Amati, L.; Amato, E.; Angelakis, E.; Arezu, J.; Atteia, J.-L.; Axelsson, M.; Bachetti, M.; Ballo, L.; Balman, S.; Bandiera, R.; Barcons, X.; Basso, S.; Baykal, A.; Becker, W.; Behar, E.; Beheshtipour, B.; Belmont, R.; Berger, E.; Bernardini, F.; Bianchi, S.; Bisnovatyi-Kogan, G.; Blasi, P.; Blay, P.; Bodaghee, A.; Boer, M.; Boettcher, M.; Bogdanov, S.; Bombaci, I.; Bonino, R.; Braga, J.; Brandt, W.; Brez, A.; Bucciantini, N.; Burderi, L.; Caiazzo, I.; Campana, R.; Campana, S.; Capitanio, F.; Cappi, M.; Cardillo, M.; Casella, P.; Catmabacak, O.; Cenko, B.; Cerda-Duran, P.; Cerruti, C.; Chaty, S.; Chauvin, M.; Chen, Y.; Chenevez, J.; Chernyakova, M.; Cheung, C. C. Teddy; Christodoulou, D.; Connell, P.; Corbet, R.; Coti Zelati, F.; Covino, S.; Cui, W.; Cusumano, G.; D'Ai, A.; D'Ammando, F.; Dadina, M.; Dai, Z.; De Rosa, A.; de Ruvo, L.; Degenaar, N.; Del Santo, M.; Del Zanna, L.; Dewangan, G.; Di Cosimo, S.; Di Lalla, N.; Di Persio, G.; Di Salvo, T.; Dias, T.; Done, C.; Dovciak, M.; Doyle, G.; Ducci, L.; Elsner, R.; Enoto, T.; Escada, J.; Esposito, P.; Eyles, C.; Fabiani, S.; Falanga, M.; Falocco, S.; Fan, Y.; Fender, R.; Feroci, M.; Ferrigno, C.; Forman, W.; Foschini, L.; Fragile, C.; Fuerst, F.; Fujita, Y.; Gasent-Blesa, J. L.; Gelfand, J.; Gendre, B.; Ghirlanda, G.; Ghisellini, G.; Giroletti, M.; Goetz, D.; Gogus, E.; Gomez, J.-L.; Gonzalez, D.; Gonzalez-Riestra, R.; Gotthelf, E.; Gou, L.; Grandi, P.; Grinberg, V.; Grise, F.; Guidorzi, C.; Gurlebeck, N.; Guver, T.; Haggard, D.; Hardcastle, M.; Hartmann, D.; Haswell, C.; Heger, A.; Hernanz, M.; Heyl, J.; Ho, L.; Hoormann, J.; Horak, J.; Huovelin, J.; Huppenkothen, D.; Iaria, R.; Inam Sitki, C.; Ingram, A.; Israel, G.; Izzo, L.; Burgess, M.; Jackson, M.; Ji, L.; Jiang, J.; Johannsen, T.; Jones, C.; Jorstad, S.; Kajava, J. J. E.; Kalamkar, M.; Kalemci, E.; Kallman, T.; Kamble, A.; Kislat, F.; Kiss, M.; Klochkov, D.; Koerding, E.; Kolehmainen, M.; Koljonen, K.; Komossa, S.; Kong, A.; Korpela, S.; Kowalinski, M.; Krawczynski, H.; Kreykenbohm, I.; Kuss, M.; Lai, D.; Lan, M.; Larsson, J.; Laycock, S.; Lazzati, D.; Leahy, D.; Li, H.; Li, J.; Li, L.-X.; Li, T.; Li, Z.; Linares, M.; Lister, M.; Liu, H.; Lodato, G.; Lohfink, A.; Longo, F.; Luna, G.; Lutovinov, A.; Mahmoodifar, S.; Maia, J.; Mainieri, V.; Maitra, C.; Maitra, D.; Majczyna, A.; Maldera, S.; Malyshev, D.; Manfreda, A.; Manousakis, A.; Manuel, R.; Margutti, R.; Marinucci, A.; Markoff, S.; Marscher, A.; Marshall, H.; Massaro, F.; McLaughlin, M.; Medina-Tanco, G.; Mehdipour, M.; Middleton, M.; Mignani, R.; Mimica, P.; Mineo, T.; Mingo, B.; Miniutti, G.; Mirac, S. M.; Morlino, G.; Motlagh, A. V.; Motta, S.; Mushtukov, A.; Nagataki, S.; Nardini, F.; Nattila, J.; Navarro, G. J.; Negri, B.; Negro, Matteo; Nenonen, S.; Neustroev, V.; Nicastro, F.; Norton, A.; Nucita, A.; O'Brien, P.; O'Dell, S.

    2016-07-01

    XIPE, the X-ray Imaging Polarimetry Explorer, is a mission dedicated to X-ray Astronomy. At the time of writing XIPE is in a competitive phase A as fourth medium size mission of ESA (M4). It promises to reopen the polarimetry window in high energy Astrophysics after more than 4 decades thanks to a detector that efficiently exploits the photoelectric effect and to X-ray optics with large effective area. XIPE uniqueness is time-spectrally-spatially- resolved X-ray polarimetry as a breakthrough in high energy astrophysics and fundamental physics. Indeed the payload consists of three Gas Pixel Detectors at the focus of three X-ray optics with a total effective area larger than one XMM mirror but with a low weight. The payload is compatible with the fairing of the Vega launcher. XIPE is designed as an observatory for X-ray astronomers with 75 % of the time dedicated to a Guest Observer competitive program and it is organized as a consortium across Europe with main contributions from Italy, Germany, Spain, United Kingdom, Poland, Sweden.

  20. Saturated fat consumption and the Theory of Planned Behaviour: exploring additive and interactive effects of habit strength.

    PubMed

    de Bruijn, Gert-Jan; Kroeze, Willemieke; Oenema, Anke; Brug, Johannes

    2008-09-01

    The additive and interactive effects of habit strength in the explanation of saturated fat intake were explored within the framework of the Theory of Planned Behaviour (TPB). Cross-sectional data were gathered in a Dutch adult sample (n=764) using self-administered questionnaires and analyzed using hierarchical regression analyses and simple slope analyses. Results showed that habit strength was a significant correlate of fat intake (beta=-0.11) and significantly increased the amount of explained variance in fat intake (R(2-change)=0.01). Furthermore, based on a significant interaction effect (beta=0.11), simple slope analyses revealed that intention was a significant correlate of fat intake for low levels (beta=-0.29) and medium levels (beta=-0.19) of habit strength, but a weaker and non-significant correlate for high levels (beta=-0.07) of habit strength. Higher habit strength may thus make limiting fat intake a non-intentional behaviour. Implications for information and motivation-based interventions are discussed.

  1. Measurements of Sheath Currents and Equilibrium Potential on the Explorer VIII Satellite (1960 xi)

    NASA Technical Reports Server (NTRS)

    Bourdeau, R. E.; Donley, J. L.; Serbu, G. P.; Whipple, E. C., Jr.

    1961-01-01

    Experimental data were obtained from the Explorer VIII satellite on five parameters pertinent to the problem of the interaction of space vehicles with an ionized atmosphere. The five parameters are: photoemission current due to electrons emitted from the satellite surfaces as a result of solar radiation; electron and positive ion currents due to the diffusion of charged particles from the medium to the spacecraft; the vehicle potential relative to the medium, and the ambient electron temperature. Included in the experimental data is the aspect dependence of the photoemission and diffusion currents. On the basis of the observations, certain characteristics of the satellite's plasma sheath are postulated.

  2. Carbofuran biodegradation in brackish groundwater and its effect on the hydraulic properties of the porous medium

    NASA Astrophysics Data System (ADS)

    Amiaz, Yanai; Ronen, Zeev; Adar, Eilon; Weisbrod, Noam

    2015-04-01

    A chalk fractured aquitard beneath an industrial site is subjected to intense contamination due to percolation of contaminants from the different facilities operating at the site. In order to reduce further contamination, draining trenches were excavated and filled with coarse gravel (3-4 cm in diameter) forming a porous medium, to which the contaminated groundwater discharges from the fractures surrounding the trenches. This research is aimed at establishing a biodegrading process of high efficiency and performance within the draining trenches. The research includes both field and laboratory experiments. An experimental setup of five columns (50 cm length and 4.5 cm in diameter) was constructed under highly controlled conditions. Over the course of the experiments, the columns were filled with different particle sizes and placed in a temperature controlled chamber. Filtered groundwater (0.2 µm) from the site groundwater, enriched by a model contaminant carbofuran (CRF), was injected to the columns; as two of the columns were inoculated by CRF degrading microorganisms native in the site's groundwater, two columns were inoculated by CRF degrading bacteria from the external environment, and one column was used as a control. During the experiment, measurements were taken from different locations along each column. These include: (a) CRF concentration and (b) hydraulic pressure and solution viscosity (in order to obtain the changes in permeability). A tracer test using uranine was carried out in parallel, in order to obtain the changes in hydraulic parameters. Correlating CRF concentration variations to changes of hydraulic parameters enable the deduction due to the effect that biological activity (under different temperature regimes) has on the hydraulic properties of the porous medium and its effect on the process of contaminant groundwater bodies' remediation. Preliminary results suggest that although biodegradation occurs, microbial activity has minor effect on the hydraulic properties of the porous medium under the explored conditions.

  3. Hypoosmotic swelling modifies glutamate-glutamine cycle in the cerebral cortex and in astrocyte cultures

    PubMed Central

    Hyzinski-García, María C.; Vincent, Melanie Y.; Haskew-Layton, Renée E.; Dohare, Preeti; Keller, Richard W.; Mongin, Alexander A.

    2011-01-01

    In our previous work, we found that perfusion of the rat cerebral cortex with hypoosmotic medium triggers massive release of the excitatory amino acid L-glutamate but decreases extracellular levels of L-glutamine (R.E. Haskew-Layton et al., PLoS ONE, 3: e3543). The release of glutamate was linked to activation of volume-regulated anion channels (VRAC), while mechanism(s) responsible for alterations in extracellular glutamine remained unclear. When mannitol was added to the hypoosmotic medium in order to reverse reductions in osmolarity, changes in microdialysate levels of glutamine were prevented, indicating an involvement of cellular swelling. Since the main source of brain glutamine is astrocytic synthesis and export, we explored the impact of hypoosmotic medium on glutamine synthesis and transport in rat primary astrocyte cultures. In astrocytes, a 40% reduction in medium osmolarity moderately stimulated the release of L-[3H]glutamine by ~2-fold and produced no changes in L-[3H]glutamine uptake. In comparison, hypoosmotic medium stimulated the release of glutamate (traced with D[3H]aspartate) by more than 20-fold. In whole-cell enzymatic assays, we discovered that hypoosmotic medium caused a 20% inhibition of astrocytic conversion of L[3H]glutamate into L-[3H]glutamine by glutamine synthetase. Using an HPLC assay we further found a 35% reduction in intracellular levels of endogenous glutamine. Overall, our findings suggest that cellular swelling (1) inhibits astrocytic glutamine synthetase activity, and (2) reduces substrate availability for this enzyme due to the activation of VRAC. These combined effects likely lead to reductions in astrocytic glutamine export in vivo and may partially explain occurrence of hyperexcitability and seizures in human hyponatremia. PMID:21517854

  4. Controlling Propagation Properties of Surface Plasmon Polariton at Terahertz Frequency

    NASA Astrophysics Data System (ADS)

    Gupta, Barun

    Despite great scientific exploration since the 1900s, the terahertz range is one of the least explored regions of electromagnetic spectrum today. In the field of plasmonics, texturing and patterning allows for control over electromagnetic waves bound to the interface between a metal and the adjacent dielectric medium. The surface plasmon-polaritons (SPPs) display unique dispersion characteristics that depend upon the plasma frequency of the medium. In the long wavelength regime, where metals are highly conductive, such texturing can create an effective medium that can be characterized by an effective plasma frequency that is determined by the geometrical parameters of the surface structure. The terahertz (THz) spectral range offers unique opportunities to utilize such materials. This thesis describes a number of terahertz plasmonic devices, both passive and active, fabricated using different techniques. As an example, inkjet printing is exploited for fabricating two-dimensional plasmonic devices. In this case, we demonstrated the terahertz plasmonic structures in which the conductivity of the metallic film is varied spatially in order to further control the plasmonic response. Using a commercially available inkjet printers, in which one cartridge is filled with conductive silver ink and a second cartridge is filled with resistive carbon ink, computer generated drawings of plasmonic structures are printed in which the individual printed dots can have differing amounts of the two inks, thereby creating a spatial variation in the conductivity. The inkjet printing technique is limited to the two-dimensional structurers. In order to expand the capability of printing complex terahertz devices, which cannot otherwise be fabricated using standard fabricating techniques, we employed 3D printing techniques. 3D printing techniques using polymers to print out the complex structures. In the realm of active plasmonic devices, a wide range of innovative approaches have been developed utilizing a variety of materials. We discuss the use of SMAs for terahertz (THz) plasmonics that allows for switching between different physical geometries corresponding to different electromagnetic responses.

  5. "I Learned Quite a Lot of the Maths Stuff Now That I Think of It": Maori Medium Students Reflecting on Their Initial Teacher Education

    ERIC Educational Resources Information Center

    Hawera, Ngarewa; Taylor, Merilyn

    2017-01-01

    Research involving preservice or initial teacher education (ITE) indicates that mathematics education is a vital component of study. Little is known however, of indigenous student views of their compulsory mathematics education courses for a teaching degree. This research contributes to that knowledge space as it explores Maori medium ITE…

  6. Effectiveness of patient simulation in nursing education: meta-analysis.

    PubMed

    Shin, Sujin; Park, Jin-Hwa; Kim, Jung-Hee

    2015-01-01

    The use of simulation as an educational tool is becoming increasingly prevalent in nursing education, and a variety of simulators are utilized. Based on the results of these studies, nursing facilitators must find ways to promote effective learning among students in clinical practice and classrooms. To identify the best available evidence about the effects of patient simulation in nursing education through a meta-analysis. This study explores quantitative evidence published in the electronic databases: EBSCO, Medline, ScienceDirect, and ERIC. Using a search strategy, we identified 2503 potentially relevant articles. Twenty studies were included in the final analysis. We found significant post-intervention improvements in various domains for participants who received simulation education compared to the control groups, with a pooled random-effects standardized mean difference of 0.71, which is a medium-to-large effect size. In the subgroup analysis, we found that simulation education in nursing had benefits, in terms of effect sizes, when the effects were evaluated through performance, the evaluation outcome was psychomotor skills, the subject of learning was clinical, learners were clinical nurses and senior undergraduate nursing students, and simulators were high fidelity. These results indicate that simulation education demonstrated medium to large effect sizes and could guide nurse educators with regard to the conditions under which patient simulation is more effective than traditional learning methods. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Development of a Single-Pass Amplifier for an Optical Stochastic Cooling Proof-of-Principle Experiment at Fermilab's IOTA Facility

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

    Andorf, M. B.; Lebedev, V. A.; Piot, P.

    2015-06-01

    Optical stochastic cooling (OSC) is a method of beam cooling which is expected to provide cooling rates orders of magnitude larger than ordinary stochastic cooling. Light from an undulator (the pickup) is amplified and fed back onto the particle beam via another undulator (the kicker). Fermilab is currently exploring a possible proof-of-principle experiment of the OSC at the integrable-optics test accelerator (IOTA) ring. To implement effective OSC a good correction of phase distortions in the entire band of the optical amplifier is required. In this contribution we present progress in experimental characterization of phase distortions associated to a Titanium Sapphiremore » crystal laser-gain medium (a possible candidate gain medium for the OSC experiment to be performed at IOTA). We also discuss a possible option for a mid-IR amplifier« less

  8. Observation of acoustic Dirac-like cone and double zero refractive index

    PubMed Central

    Dubois, Marc; Shi, Chengzhi; Zhu, Xuefeng; Wang, Yuan; Zhang, Xiang

    2017-01-01

    Zero index materials where sound propagates without phase variation, holds a great potential for wavefront and dispersion engineering. Recently explored electromagnetic double zero index metamaterials consist of periodic scatterers whose refractive index is significantly larger than that of the surrounding medium. This requirement is fundamentally challenging for airborne acoustics because the sound speed (inversely proportional to the refractive index) in air is among the slowest. Here, we report the first experimental realization of an impedance matched acoustic double zero refractive index metamaterial induced by a Dirac-like cone at the Brillouin zone centre. This is achieved in a two-dimensional waveguide with periodically varying air channel that modulates the effective phase velocity of a high-order waveguide mode. Using such a zero-index medium, we demonstrated acoustic wave collimation emitted from a point source. For the first time, we experimentally confirm the existence of the Dirac-like cone at the Brillouin zone centre. PMID:28317927

  9. The impact of communication on human behaviour in times of crisis.

    PubMed

    MacLeod, Andrew

    Decision makers have constantly sought to find the most appropriate ways to use communication to influence behaviour during times of crises to assist in their recovery. This paper will investigate why policy makers wish to utilise effective crisis communications and explore the importance of crisis communication on influencing human behaviour in a time of crisis as well as the influence that the medium of communication can have. It will be noted that the medium of the message is important to ensure that the correct audience has been reached. This paper will suggest that, for decision makers to maximise the impact of crisis communications during a crisis, they must utilise rhetoric and cognitive response theory. It will also be suggested that the most importance factor in influencing behaviour in a time of crisis is that communications are provided from a credible source and are empathic in nature.

  10. Use of magnetic sails for advanced exploration missions

    NASA Technical Reports Server (NTRS)

    Andrews, Dana G.; Zubrin, Robert M.

    1990-01-01

    The magnetic sail, or magsail, is a field effect device which interacts with the ambient solar wind or interstellar medium over a considerable volume of space to generate drag and lift forces. Two theories describing the method of thrust generation are analyzed and data results are presented. The techniques for maintaining superconductor temperatures in interplanetary space are analyzed and low risk options presented. Comparisons are presented showing mission performance differences between currently proposed spacecraft using chemical and electric propulsion systems, and a Magsail propelled spacecraft capable of generating an average thrust of 250 Newtons at a radius of one A.U. The magsail also provides unique capabilities for interstellar missions, in that at relativistic speeds the magnetic field would ionize and deflect the interstellar medium producing a large drag force. This would make it an ideal brake for decelerating a spacecraft from relativistic speeds and then maneuvering within the target star system.

  11. Parental Experiences of Raising a Child With Medium Chain Acyl-CoA Dehydrogenase Deficiency.

    PubMed

    Piercy, Hilary; Machaczek, Katarzyna; Ali, Parveen; Yap, Sufin

    2017-01-01

    Newborn screening enabling early diagnosis of medium chain acyl-CoA dehydrogenase deficiency (MCADD) has dramatically improved health outcomes in children with MCADD. Achieving those outcomes depends on effective management by parents. Understanding parental management strategies and associated anxieties and concerns is needed to inform provision of appropriate care and support. Semistructured interviews were conducted with a purposive sample of parents of children aged 2 to 12 years. Thematic analysis identified two main themes. Managing dietary intake examined how parents managed day-to-day dietary intake to ensure adequate intake and protection of safe fasting intervals. Managing and preventing illness events explored parental experiences of managing illness events and their approach to preventing these events. Management strategies were characterized by caution and vigilance and influenced by a lack of confidence in others to manage the condition. The study identifies the need for increased awareness of the condition, particularly in relation to emergency treatment.

  12. Isotopic patterns in caps and stipes in sporocarps reveal patterns of organic nitrogen use by ectomycorrhizal fungi

    NASA Astrophysics Data System (ADS)

    Hobbie, Erik; Ouimette, Andrew; Chen, Janet

    2016-04-01

    Current ecosystem models use inorganic nitrogen as the currency of nitrogen acquisition by plants. However, many trees may gain access to otherwise unavailable soil resources, such as soil organic nitrogen, through their symbioses with ectomycorrhizal fungi, and this pathway of nitrogen acquisition may therefore be important in understanding plant responses to environmental change. Different functional groups of ectomycorrhizal fungi vary in their ability to enzymatically access protein and other soil resources. Such fungal parameters as hyphal hydrophobicity, the presence of rhizomorphs (long-distance transport structures), and exploration strategies (e.g., short-distance versus long-distance, mat formation) correspond with how fungi interact with and explore the environment, and the proportions of different exploration types present will shift along environmental gradients such as nitrogen availability. Isotopic differences between caps and stipes may provide a means to test for organic nitrogen use, since caps and stipes differ in δ13C and δ15N as a result of variable proportions of protein and other classes of compounds, and protein should differ isotopically among de novo synthesis, litter sources, and soil sources. Here, we propose that (1) isotopic differences between caps and stipes could be related to organic nitrogen uptake and to the δ13C and δ15N values of different pools of soil-derived or de novo-synthesized amino acids; (2) these isotopic differences will reflect greater acquisition of soil-derived organic nitrogen by exploration types of greater enzymatic capabilities to degrade recalcitrant nitrogen forms, specifically long-distance, medium-distance fringe, and medium-distance mat exploration types. To test these hypotheses, we use a dataset of isotopic values, %N, and %C in 208 cap/stipe samples collected from Oregon, western USA. δ13C differences in caps and stipes in a multiple regression model had an adjusted r2 of 0.292 (p < 0.0001), and were explained best by exploration type (45% of explained variance), the interaction of exploration type and %Ncap-stipe (20%), the interaction of exploration type and %Ncap/stipe (22%), %Ccap-stipe (8%), and %Ncap-stipe (5%). δ15N differences between caps and stipes in a multiple regression model had an adjusted r2 of 0.486 (p < 0.0001), and were explained best by exploration type (47% of explained variance), the interaction of exploration type and %Ncap-stipe (26%), the interaction of exploration type and %Ncap/stipe (14%), %Ncap/stipe (11%),and %Ccap-stipe (2%). We argue that these differences in the 13C and 15N enrichment of caps relative to stipes reflect not only shifts in the proportions of protein and carbohydrates, but also differences in the extent of fluxes and the δ13C and δ15N signatures of soil- and litter-derived organic nitrogen taken up by these fungi. We also propose equations to quantify this uptake. Organic nitrogen from litter (lower δ13C and δ15N) may be incorporated by medium-distance mat, short-distance, and contact exploration types of ectomycorrhizal fungi, whereas long-distance and medium-distance fringe exploration types appeared to incorporate deeper soil organic nitrogen.

  13. Science Drivers for Polarimetric Exploration

    NASA Astrophysics Data System (ADS)

    Yanamandra-Fisher, Padma

    2017-04-01

    The versatility of polarimetric exploration is exploited to address: (1) understanding the formation of planetary systems and their diversity; and (2) search for habitability. Polarized light occurs in three states: unpolarized, linear and circularized. Each mode of polarized light provides information about the scattering medium, from atmospheres to search for signatures of habitability. Spectral dependence of polarization is important to separate the macroscopic (bulk) properties of the scattering medium from the microscopic (particulate) properties of the scattering medium. Linear polarization of reflected light by solar system objects provides insight into the scattering characteristics of aerosols and hazes in atmospheres and surficial properties of atmosphereless objects, circular polarization and related chirality (or handedness, a property of molecules that exhibit mirror-image symmetry, similar to right and left hands) can serve as diagnostic of biological activity. Atmospheric phenomena such as rainbows, clouds and haloes exhibit polarimetric signatures that can be used as diagnostics to probe the atmosphere and may be possible to extend this approach to other planets and exoplanets. Biological molecules exhibit an inherent handedness or circular polarization or chirality, assisting in search for the identification of astrobiological material in the solar system. Polarimetry is also utilized in the exploration of comets, asteroids, dust/regoliths. Renewed efforts for ground-based polarimetry are emerging, from probing planetary atmospheres to the study of magnetic field lines and taxonomy of asteroids. While imaging and spectroscopy are routinely performed by amateurs, there is growing interest and progress in developing polarimetric exploration amongst the amateur community, with encouraging results.I will present a review of these efforts and the goal to create a global " PACA* Polarimetry Network" of observers, modelers and instrument experts to fully utilize polarimetric exploration of planetary systems, and identify potential partnerships. * PACA stands for Pro-Am Collaborative Astronomy

  14. Artist's Concept of Wide-field Infrared Survey Explorer (WISE)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Artist's concept of Wide-field Infrared Survey Explorer.

    A new NASA mission will scan the entire sky in infrared light in search of nearby cool stars, planetary construction zones and the brightest galaxies in the universe.

    Called the Wide-field Infrared Survey Explorer, the mission has been approved to proceed into the preliminary design phase as the next in NASA's Medium-class Explorer program of lower cost, highly focused, rapid-development scientific spacecraft. It is scheduled to launch in 2008.

  15. Virtual reality and planetary exploration

    NASA Technical Reports Server (NTRS)

    Mcgreevy, Michael W.

    1992-01-01

    NASA-Ames is intensively developing virtual-reality (VR) capabilities that can extend and augment computer-generated and remote spatial environments. VR is envisioned not only as a basis for improving human/machine interactions involved in planetary exploration, but also as a medium for the more widespread sharing of the experience of exploration, thereby broadening the support-base for the lunar and planetary-exploration endeavors. Imagery representative of Mars are being gathered for VR presentation at such terrestrial sites as Antarctica and Death Valley.

  16. Three-Nucleon Forces and Triplet Pairing in Neutron Matter

    NASA Astrophysics Data System (ADS)

    Papakonstantinou, P.; Clark, J. W.

    2017-12-01

    The existence of superfluidity of the neutron component in the core of a neutron star, associated specifically with triplet P-wave pairing, is currently an open question that is central to interpretation of the observed cooling curves and other neutron-star observables. Ab initio theoretical calculations aimed at resolving this issue face unique challenges in the relevant high-density domain, which reaches beyond the saturation density of symmetrical nuclear matter. These issues include uncertainties in the three-nucleon (3N) interaction and in the effects of strong short-range correlations—and more generally of in-medium modification of nucleonic self-energies and interactions. A survey of existing solutions of the gap equations in the triplet channel demonstrates that the net impact on the gap magnitude of 3N forces, coupled channels, and mass renormalization shows extreme variation dependent on specific theoretical inputs, in some cases even pointing to the absence of a triplet gap, thus motivating a detailed analysis of competing effects within a well-controlled model. In the present study, we track the effects of the 3N force and in-medium modifications in the representative case of the ^3P_2 channel, based on the Argonne v_{18} two-nucleon (2N) interaction supplemented by 3N interactions of the Urbana IX family. Sensitivity of the results to the input interaction is clearly demonstrated. We point out consistency issues with respect to the simultaneous treatment of 3N forces and in-medium effects, which warrant further investigation. We consider this pilot study as the first step toward a systematic and comprehensive exploration of coupled-channel ^3P F_2 pairing using a broad range of 2N and 3N interactions from the current generation of refined semi-phenomenological models and models derived from chiral effective field theory.

  17. 4D printing of a self-morphing polymer driven by a swellable guest medium.

    PubMed

    Su, Jheng-Wun; Tao, Xiang; Deng, Heng; Zhang, Cheng; Jiang, Shan; Lin, Yuyi; Lin, Jian

    2018-01-31

    There is a significant need of advanced materials that can be fabricated into functional devices with defined three-dimensional (3D) structures for application in tissue engineering, flexible electronics, and soft robotics. This need motivates an emerging four-dimensional (4D) printing technology, by which printed 3D structures consisting of active materials can transform their configurations over time in response to stimuli. Despite the ubiquity of active materials in performing self-morphing processes, their potential for 4D printing has not been fully explored to date. In this study, we demonstrate 4D printing of a commercial polymer, SU-8, which has not been reported to date in this field. The working principle is based on a self-morphing process of the printed SU-8 structures through spatial control of the swelling medium inside the polymer matrix by a modified process. To understand the self-morphing behavior, fundamental studies on the effect of the geometries including contours and filling patterns were carried out. A soft electronic device as an actuator was demonstrated to realize an application of this programmable polymer using the 3D printing technology. These studies provide a new paradigm for application of SU-8 in 4D printing, paving a new route to the exploration of more potential candidates by this demonstrated strategy.

  18. Exploring the Connection between Graphic Novel and Film

    ERIC Educational Resources Information Center

    Dallacqua, Ashley Kaye

    2012-01-01

    In the spring of 2010, the author had the pleasure of working with four fifth graders, exploring reading engagement with graphic novels. During her research study, she became inspired by the connections these fifth graders made between the graphic novels they discussed and the film medium and ultimately concluded that this connection contributed…

  19. Human Resource Development in Mauritius: Context, Challenges and Opportunities

    ERIC Educational Resources Information Center

    Garavan, Thomas N.; Neeliah, Harris; Auckloo, Raj; Ragaven, Raj

    2016-01-01

    Purpose: The purpose of this paper is to explore human resource development (HRD) in Mauritius and the challenges and opportunities faced by organisations in different sectors in adopting HRD practices. Findings: This special issue presents four papers that explore dimensions of HRD in public sector, small- and medium-sized enterprises (SMEs) and…

  20. Effects of calcium channel blockers on the contractility of the filariid Acanthocheilonema viteae.

    PubMed

    Christ, D; Stillson, T

    1992-01-01

    The role of calcium in muscle contractility was explored in the filarial nematode Acanthocheilonema viteae (Dipetalonema viteae). The parasite was slit open longitudinally and mounted in a smooth-muscle chamber that had been filled with aerated (95% N2/5% CO2) physiological solution at 37 degrees C. Nifedipine (10(-6) M) and cadmium (3 x 10(-5) M) reduced the spontaneous isotonic contractions of A. viteae, whereas verapamil (10(-5) M) and diltiazem (10(-5) M) enhanced them. The effects of nifedipine and verapamil did not appear to be due to the solvent ethanol. All of the drugs reduced the maximal contraction induced by acetylcholine (ACh, 10(-5) M), although nifedipine was the most potent. After the exposure of worm preparations to a calcium-free medium containing ethyleneglycol-bis-(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA, 10(-4) M) for 1 h, application of ACh (10(-5) M) induced a small, transient contraction. Subsequent applications of ACh in this medium had no effect. Thus, the nematode muscle contraction appears to depend on extracellular calcium. Nifedipine, diltiazem, and verapamil could act by reducing the calcium influx across the muscle membrane.

  1. Naringin promotes osteogenic differentiation of bone marrow stromal cells by up-regulating Foxc2 expression via the IHH signaling pathway

    PubMed Central

    Lin, Fei-xiang; Du, Shi-xin; Liu, De-zhong; Hu, Qin-xiao; Yu, Guo-yong; Wu, Chu-cheng; Zheng, Gui-zhou; Xie, Da; Li, Xue-dong; Chang, Bo

    2016-01-01

    Naringin is an active compound extracted from Rhizoma Drynariae, and studies have revealed that naringin can promote proliferation and osteogenic differentiation of bone marrow stromal cells (BMSCs). In this study, we explored whether naringin could promote osteogenic differentiation of BMSCs by upregulating Foxc2 expression via the Indian hedgehog (IHH) signaling pathway. BMSCs were cultured in basal medium, basal medium with naringin, osteogenic induction medium, osteogenic induction medium with naringin and osteogenic induction medium with naringin in the presence of the IHH inhibitor cyclopamine (CPE). We examined cell proliferation by using a WST-8 assay, and differentiation by Alizarin Red S staining (for mineralization) and alkaline phosphatase (ALP) activity. In addition, we detected core-binding factor α1 (Cbfα1), osteocalcin (OCN), bone sialoprotein (BSP), peroxisome proliferation-activated receptor gamma 2 (PPARγ2) and Foxc2 expression by using RT-PCR. We also determined Foxc2 and IHH protein levels by western blotting. Naringin increased the mineralization of BMSCs, as shown by Alizarin red S assays, and induced ALP activity. In addition, naringin significantly increased the mRNA levels of Foxc2, Cbfα1, OCN, and BSP, while decreasing PPARγ2 mRNA levels. Furthermore, the IHH inhibitor CPE inhibited the osteogenesis-potentiating effects of naringin. Naringin increased Foxc2 and stimulated the activation of IHH, as evidenced by increased expression of proteins that were inhibited by CPE. Our findings indicate that naringin promotes osteogenic differentiation of BMSCs by up-regulating Foxc2 expression via the IHH signaling pathway. PMID:27904711

  2. Naringin promotes osteogenic differentiation of bone marrow stromal cells by up-regulating Foxc2 expression via the IHH signaling pathway.

    PubMed

    Lin, Fei-Xiang; Du, Shi-Xin; Liu, De-Zhong; Hu, Qin-Xiao; Yu, Guo-Yong; Wu, Chu-Cheng; Zheng, Gui-Zhou; Xie, Da; Li, Xue-Dong; Chang, Bo

    2016-01-01

    Naringin is an active compound extracted from Rhizoma Drynariae, and studies have revealed that naringin can promote proliferation and osteogenic differentiation of bone marrow stromal cells (BMSCs). In this study, we explored whether naringin could promote osteogenic differentiation of BMSCs by upregulating Foxc2 expression via the Indian hedgehog (IHH) signaling pathway. BMSCs were cultured in basal medium, basal medium with naringin, osteogenic induction medium, osteogenic induction medium with naringin and osteogenic induction medium with naringin in the presence of the IHH inhibitor cyclopamine (CPE). We examined cell proliferation by using a WST-8 assay, and differentiation by Alizarin Red S staining (for mineralization) and alkaline phosphatase (ALP) activity. In addition, we detected core-binding factor α1 (Cbfα1), osteocalcin (OCN), bone sialoprotein (BSP), peroxisome proliferation-activated receptor gamma 2 (PPARγ2) and Foxc2 expression by using RT-PCR. We also determined Foxc2 and IHH protein levels by western blotting. Naringin increased the mineralization of BMSCs, as shown by Alizarin red S assays, and induced ALP activity. In addition, naringin significantly increased the mRNA levels of Foxc2, Cbfα1, OCN, and BSP, while decreasing PPARγ2 mRNA levels. Furthermore, the IHH inhibitor CPE inhibited the osteogenesis-potentiating effects of naringin. Naringin increased Foxc2 and stimulated the activation of IHH, as evidenced by increased expression of proteins that were inhibited by CPE. Our findings indicate that naringin promotes osteogenic differentiation of BMSCs by up-regulating Foxc2 expression via the IHH signaling pathway.

  3. A Multi-Wavelength Study of the Hot Component Of The Interstellar Medium

    NASA Technical Reports Server (NTRS)

    Nichols, Joy; West, Donald K. (Technical Monitor)

    2001-01-01

    This research focuses on the kinematics and evolution of the hot phase of the interstellar medium in the Galaxy. The plan is to measure the UV spectra for all hot stars observed with International Ultraviolet Explorer (IUE), in order to identify and measure the main component and any high velocity components to the interstellar lines. A total of 1200 stars are candidates for inclusion in this study.

  4. [Protective effect of amlodipine on the cytotoxicity induced by contrast media in human kidney cells].

    PubMed

    Zhou, Xiao-rong; Duan, Shao-bin; Peng, You-ming; Liu, Fu-you; Ye, Yun; Liu, Rui-hong; Li, Gui-yuan

    2007-10-01

    To explore the protective effect of amlodipine on the cytotoxicity induced by contrast media (meglumine diatrizoate) in human kidney cells (HKC). An HKC line was used. The experiment was divided into 4 groups: a model group (diatrizoate 111g/L), a prevention group (diatrizoate 111g/L+amlodipine 10(-5)mol/L), an amlodipine control group (amlodipine 10(-5)mol/L), and a culture medium control group (simple none blood serum DMEM-F12 medium). Cytotoxicity induced by meglumine diatrizoate was analysed by methyl thiazolyl tetrazolium (MTT) test, lactate dehydrogenase (LDH) assay, Hochest33258 fluorescence stained cytospins, and flow cytometric DNA analysis. The protein expression of Bax was determined by Western blot, and caspase-3 activity was examined by fluorometric method. In the prevention group, the cell viability increased significantly (P<0.05), LDH levels decreased (P<0.05), and the apoptosis was lower than that of the model group (P<0.05) .Bax protein expression and caspase 3 activity decreased (P<0.05). Amlodipine can inhibit the HKC apoptosis and protect the renal tubule cell from injury induced by meglumine diatrizoate.

  5. [Progesterone Promotes Human Bone Marrow Mesenchymal Stem Cells to Synthesize Fibronectin via ERK Pathway].

    PubMed

    Wu, Zhen-Yong; Chen, Jing-Li; Huang, Shu; Zhang, Hui; Wang, Fang; Wang, Yan; Bi, Xiao-Yun; Guo, Zi-Kuan

    2015-12-01

    To investigate whether the progesterone can promote fibronection (FN) synthesis by human bone marrow mesenchymal stem cells (MSCs) and to explore the potential underlying mechanism. The human bone marrow MSCs were cultured in a serum-free medium with progesterone for 72 hours, the MTT test was performed to observe the proliferation status and adhension ability of the treated cells. Western blot was used to detect the content of FN in MSDs with GAPDH as the internal reference, the phosphorylation of ERK1/2, as well as the FN content in MSC treated by PD98059, a specific inhibitor of ERK1/2. The progesterone at a range of certain doses not effect on the proliferation of human bone marrow MSCs. Progesterone (25 µg/L) treatment enhanced the FN expression and adherent ability of marrow MSCs. Progesterone could induce prompt phosphorylation of ERK 1/2 and its promoting effects on FN synthesis was reversed by PD98059. The progesterone can promote FN synthesis by human bone marrow MSCs via ERK 1/2 pathway, and it might be used to culture MSCs in serum-free medium.

  6. Protein Corona Prevents TiO2 Phototoxicity.

    PubMed

    Garvas, Maja; Testen, Anze; Umek, Polona; Gloter, Alexandre; Koklic, Tilen; Strancar, Janez

    2015-01-01

    TiO2 nanoparticles have generally low toxicity in the in vitro systems although some toxicity is expected to originate in the TiO2-associated photo-generated radical production, which can however be modulated by the radical trapping ability of the serum proteins. To explore the role of serum proteins in the phototoxicity of the TiO2 nanoparticles we measure viability of the exposed cells depending on the nanoparticle and serum protein concentrations. Fluorescence and spin trapping EPR spectroscopy reveal that the ratio between the nanoparticle and protein concentrations determines the amount of the nanoparticles' surface which is not covered by the serum proteins and is proportional to the amount of photo-induced radicals. Phototoxicity thus becomes substantial only at the protein concentration being too low to completely coat the nanotubes' surface. These results imply that TiO2 nanoparticles should be applied with ligands such as proteins when phototoxic effects are not desired - for example in cosmetics industry. On the other hand, the nanoparticles should be used in serum free medium or any other ligand free medium, when phototoxic effects are desired - as for efficient photodynamic cancer therapy.

  7. Overview of GX launch services by GALEX

    NASA Astrophysics Data System (ADS)

    Sato, Koji; Kondou, Yoshirou

    2006-07-01

    Galaxy Express Corporation (GALEX) is a launch service company in Japan to develop a medium size rocket, GX rocket and to provide commercial launch services for medium/small low Earth orbit (LEO) and Sun synchronous orbit (SSO) payloads with a future potential for small geo-stationary transfer orbit (GTO). It is GALEX's view that small/medium LEO/SSO payloads compose of medium scaled but stable launch market due to the nature of the missions. GX rocket is a two-stage rocket of well flight proven liquid oxygen (LOX)/kerosene booster and LOX/liquid natural gas (LNG) upper stage. This LOX/LNG propulsion under development by Japan's Aerospace Exploration Agency (JAXA), is robust with comparable performance as other propulsions and have future potential for wider application such as exploration programs. GX rocket is being developed through a joint work between the industries and GX rocket is applying a business oriented approach in order to realize competitive launch services for which well flight proven hardware and necessary new technology are to be introduced as much as possible. It is GALEX's goal to offer “Easy Access to Space”, a highly reliable and user-friendly launch services with a competitive price. GX commercial launch will start in Japanese fiscal year (JFY) 2007 2008.

  8. Numerical simulation of failure behavior of granular debris flows based on flume model tests.

    PubMed

    Zhou, Jian; Li, Ye-xun; Jia, Min-cai; Li, Cui-na

    2013-01-01

    In this study, the failure behaviors of debris flows were studied by flume model tests with artificial rainfall and numerical simulations (PFC(3D)). Model tests revealed that grain sizes distribution had profound effects on failure mode, and the failure in slope of medium sand started with cracks at crest and took the form of retrogressive toe sliding failure. With the increase of fine particles in soil, the failure mode of the slopes changed to fluidized flow. The discrete element method PFC(3D) can overcome the hypothesis of the traditional continuous medium mechanic and consider the simple characteristics of particle. Thus, a numerical simulations model considering liquid-solid coupled method has been developed to simulate the debris flow. Comparing the experimental results, the numerical simulation result indicated that the failure mode of the failure of medium sand slope was retrogressive toe sliding, and the failure of fine sand slope was fluidized sliding. The simulation result is consistent with the model test and theoretical analysis, and grain sizes distribution caused different failure behavior of granular debris flows. This research should be a guide to explore the theory of debris flow and to improve the prevention and reduction of debris flow.

  9. Detection of phasic dopamine by D1 and D2 striatal medium spiny neurons.

    PubMed

    Yapo, Cedric; Nair, Anu G; Clement, Lorna; Castro, Liliana R; Hellgren Kotaleski, Jeanette; Vincent, Pierre

    2017-12-15

    Brief dopamine events are critical actors of reward-mediated learning in the striatum; the intracellular cAMP-protein kinase A (PKA) response of striatal medium spiny neurons to such events was studied dynamically using a combination of biosensor imaging in mouse brain slices and in silico simulations. Both D1 and D2 medium spiny neurons can sense brief dopamine transients in the sub-micromolar range. While dopamine transients profoundly change cAMP levels in both types of medium spiny neurons, the PKA-dependent phosphorylation level remains unaffected in D2 neurons. At the level of PKA-dependent phosphorylation, D2 unresponsiveness depends on protein phosphatase-1 (PP1) inhibition by DARPP-32. Simulations suggest that D2 medium spiny neurons could detect transient dips in dopamine level. The phasic release of dopamine in the striatum determines various aspects of reward and action selection, but the dynamics of the dopamine effect on intracellular signalling remains poorly understood. We used genetically encoded FRET biosensors in striatal brain slices to quantify the effect of transient dopamine on cAMP or PKA-dependent phosphorylation levels, and computational modelling to further explore the dynamics of this signalling pathway. Medium-sized spiny neurons (MSNs), which express either D 1 or D 2 dopamine receptors, responded to dopamine by an increase or a decrease in cAMP, respectively. Transient dopamine showed similar sub-micromolar efficacies on cAMP in both D1 and D2 MSNs, thus challenging the commonly accepted notion that dopamine efficacy is much higher on D 2 than on D 1 receptors. However, in D2 MSNs, the large decrease in cAMP level triggered by transient dopamine did not translate to a decrease in PKA-dependent phosphorylation level, owing to the efficient inhibition of protein phosphatase 1 by DARPP-32. Simulations further suggested that D2 MSNs can also operate in a 'tone-sensing' mode, allowing them to detect transient dips in basal dopamine. Overall, our results show that D2 MSNs may sense much more complex patterns of dopamine than previously thought. © 2017 The Authors. The Journal of Physiology © 2017 The Physiological Society.

  10. Ionization in the local interstellar and intergalactic media

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

    Cheng, K.

    1990-01-01

    Detailed photoionization calculations for the local interstellar medium (LISM) and the intergalactic medium (IGM) are presented. Constraints in the LISM are imposed by H I column density derived from IUE and Copernicus data toward nearby B stars and hot white dwarfs. The EUV radiation field is modeled including contributions from discrete stellar sources and from a thermal bremsstrahlung-radiative recombination spectrum emitted from the surrounding 10(exp 6) K coronal substrate. Lower limits to the fractional ionization of hydrogen and helium of 0.17 and 0.30 respectively are established. The derived limits have important implications for the interpretation of the H I andmore » He I backscattering results. The high He ionization fraction results primarily from very strong line emission below 500 A originating in the surrounding coronal substrate while the H ionization is dominated by the EUV radiation from the discrete stellar sources. The dual effects of thermal conduction and the EUV spectrum of the 10(exp 6) K plasma on ionization in the cloud skin are explored. The EUV radiation field and Auger ionization have insignificant effects on the resulting ionic column densities of Si IV, C IV, N V and O VI through the cloud skin. Calculations show that the abundances of these species are dominated by collisional ionization in the thermal conduction front. Because of a low charge exchange rate with hydrogen, the ionic column density ratios of N(C III)/N(C II) and N(N II)/N(N I) are dominated by the EUV radiation field in the local interstellar medium. These ratios should be important diagnostics for the EUV radiation field and serve as surrogate indicators of the interstellar He and H ionization fraction respectively. The same photoionization model is applied to the intergalactic medium.« less

  11. Millisecond Pulsar Timing Precision with NICER

    NASA Astrophysics Data System (ADS)

    Deneva, Julia; Ray, Paul S.; Ransom, Scott; Wood, Kent S.; Kerr, Matthew T.; Lommen, Andrea; Arzoumanian, Zaven; Black, Kevin; Gendreau, Keith C.; Lewandowska, Natalia; Markwardt, Craig B.; Price, Samuel; Winternitz, Luke

    2018-01-01

    The Neutron Star Interior Composition Explorer (NICER) is an array of 56 X-ray detectors mounted on the outside of the International Space Station. It allows high-precision timing of millisecond pulsars (MSPs) without the pulse broadening effects due to dispersion and scattering by the interstellar medium that plague radio timing. We present initial timing results from four months of NICER data on the MSPs B1937+21, B1821-24, and J0218+4232, and compare them to simulations and theoretical models for X-ray times-of-arrival, and radio observations.

  12. [Effects of Buzhong Yiqi decoction on expression of Bad, NF-κB, caspase-9, Survivin, and mTOR in nude mice with A549/DDP transplantation tumors].

    PubMed

    Liu, Ya-Li; Yi, Jia-Li; Liu, Chun-Ying

    2017-02-01

    This study was aimed to explore the effects of Buzhong Yiqi decoction on the expression levels of Bad, NF-κB, caspase-9, Survivin, and mTOR in nude mice with A549/DDP transplantation tumors.Sixty BALB/C mice were randomly divided into blank control group, tumor-bearing control group, cisplatin group and Buzhong Yiqi decoction of high, medium and low doses+cisplatin groups (hereinafter referred to as the high,medium and low combined groups). A549/DDP cells (concentration of 5×106 cells/mL)were cultured and inoculated in various groups, then the tumor-forming situations were observed. Corresponding treatment was given in all groups. Fourteen days later, immunohistochemistry and Real-time PCR methods were used to detect the expression levels of Bad, NF-κB, caspase-9, Survivin, mTOR protein and mRNA in tumors.Results showed that Buzhong Yiqi decoction combined with cisplatin could reduce the volume of transplanted tumors, and there was significant difference between medium combined group and high combined group(P<0.05). As compared with the tumor-bearing control group, the expression levels of Bad, NF-κB, Survivin and mTOR were significantly reduced in medium and high combined groups(P<0.05); the protein and mRNA expression levels of caspase-9 were gradually increased in medium combined and high combined groups(P<0.05), with statistical difference with tumor-bearing control group(P<0.05). There were statistical difference in mRNA expression of Bad, NF-κB and caspase-9 between medium combined group, high combined group and cisplatin group, low-combined group, tumor-bearing control group(P<0.05), but there was no statistical difference between cisplatin group, low-combined group, and tumor-bearing control group. In addition, there was no statistical difference between medium combined group and high combined group in protein and mRNA expression levels of various factors. Experimental results showed that Buzhong Yiqi decoction combined with cisplatin can inhibit the growth of A549/DDP transplanted tumors, and the mechanism may be associated with regulating Bad, NF-κB, caspase-9, Survivin, and mTOR levels as well as promoting apoptosis. Copyright© by the Chinese Pharmaceutical Association.

  13. The Effects of Medium Spiny Neuron Morphologcial Changes on Basal Ganglia Network under External Electric Field: A Computational Modeling Study

    PubMed Central

    Zhang, Xiaohan; Liu, Shenquan; Zhan, Feibiao; Wang, Jing; Jiang, Xiaofang

    2017-01-01

    The damage of dopaminergic neurons that innervate the striatum has been considered to be the proximate cause of Parkinson's disease (PD). In the dopamine-denervated state, the loss of dendritic spines and the decrease of dendritic length may prevent medium spiny neuron (MSN) from receiving too much excitatory stimuli from the cortex, thereby reducing the symptom of Parkinson's disease. However, the reduction in dendritic spine density obtained by different experiments is significantly different. We developed a biological-based network computational model to quantify the effect of dendritic spine loss and dendrites tree degeneration on basal ganglia (BG) signal regulation. Through the introduction of error index (EI), which was used to measure the attenuation of the signal, we explored the amount of dendritic spine loss and dendritic trees degradation required to restore the normal regulatory function of the network, and found that there were two ranges of dendritic spine loss that could reduce EI to normal levels in the case of dopamine at a certain level, this was also true for dendritic trees. However, although these effects were the same, the mechanisms of these two cases were significant difference. Using the method of phase diagram analysis, we gained insight into the mechanism of signal degradation. Furthermore, we explored the role of cortex in MSN morphology changes dopamine depletion-induced and found that proper adjustments to cortical activity do stop the loss in dendritic spines induced by dopamine depleted. These results suggested that modifying cortical drive onto MSN might provide a new idea on clinical therapeutic strategies for Parkinson's disease. PMID:29123477

  14. Interactive video gaming compared with health education in older adults with mild cognitive impairment: a feasibility study.

    PubMed

    Hughes, Tiffany F; Flatt, Jason D; Fu, Bo; Butters, Meryl A; Chang, Chung-Chou H; Ganguli, Mary

    2014-09-01

    We evaluated the feasibility of a trial of Wii interactive video gaming, and its potential efficacy at improving cognitive functioning compared with health education, in a community sample of older adults with neuropsychologically defined mild cognitive impairment. Twenty older adults were equally randomized to either group-based interactive video gaming or health education for 90 min each week for 24 weeks. Although the primary outcomes were related to study feasibility, we also explored the effect of the intervention on neuropsychological performance and other secondary outcomes. All 20 participants completed the intervention, and 18 attended at least 80% of the sessions. The majority (80%) of participants were "very much" satisfied with the intervention. Bowling was enjoyed by the most participants and was also rated the highest among the games for mental, social, and physical stimulation. We observed medium effect sizes for cognitive and physical functioning in favor of the interactive video gaming condition, but these effects were not statistically significant in this small sample. Interactive video gaming is feasible for older adults with mild cognitive impairment, and medium effect sizes in favor of the Wii group warrant a larger efficacy trial. Copyright © 2014 John Wiley & Sons, Ltd.

  15. Effects of Zinc Chelators on Aflatoxin Production in Aspergillus parasiticus

    PubMed Central

    Wee, Josephine; Day, Devin M.; Linz, John E.

    2016-01-01

    Zinc concentrations strongly influence aflatoxin accumulation in laboratory media and in food and feed crops. The presence of zinc stimulates aflatoxin production, and the absence of zinc impedes toxin production. Initial studies that suggested a link between zinc and aflatoxin biosynthesis were presented in the 1970s. In the present study, we utilized two zinc chelators, N,N,N′,N′-tetrakis (2-pyridylmethyl) ethane-1,2-diamine (TPEN) and 2,3-dimercapto-1-propanesulfonic acid (DMPS) to explore the effect of zinc limitation on aflatoxin synthesis in Aspergillus parasiticus. TPEN but not DMPS decreased aflatoxin biosynthesis up to six-fold depending on whether A. parasiticus was grown on rich or minimal medium. Although we observed significant inhibition of aflatoxin production by TPEN, no detectable changes were observed in expression levels of the aflatoxin pathway gene ver-1 and the zinc binuclear cluster transcription factor, AflR. Treatment of growing A. parasiticus solid culture with a fluorescent zinc probe demonstrated an increase in intracellular zinc levels assessed by increases in fluorescent intensity of cultures treated with TPEN compared to controls. These data suggest that TPEN binds to cytoplasmic zinc therefore limiting fungal access to zinc. To investigate the efficacy of TPEN on food and feed crops, we found that TPEN effectively decreases aflatoxin accumulation on peanut medium but not in a sunflower seeds-derived medium. From an application perspective, these data provide the basis for biological differences that exist in the efficacy of different zinc chelators in various food and feed crops frequently contaminated by aflatoxin. PMID:27271668

  16. Bacteriorhodopsin as an electronic conduction medium for biomolecular electronics.

    PubMed

    Jin, Yongdong; Honig, Tal; Ron, Izhar; Friedman, Noga; Sheves, Mordechai; Cahen, David

    2008-11-01

    Interfacing functional proteins with solid supports for device applications is a promising route to possible applications in bio-electronics, -sensors, and -optics. Various possible applications of bacteriorhodopsin (bR) have been explored and reviewed since the discovery of bR. This tutorial review discusses bR as a medium for biomolecular optoelectronics, emphasizing ways in which it can be interfaced, especially as a thin film, solid-state current-carrying electronic element.

  17. Exploring an Invisible Medium: Teacher Language Awareness among Preservice K12 Educators of English Language Learners

    ERIC Educational Resources Information Center

    Lindahl, Kristen Marie

    2013-01-01

    This study investigates the construct of Teacher Language Awareness (TLA) in a group of preservice mainstream K-12 teachers who are developing skills to work with English Language Learners (ELLs) in United States (US) public school contexts. Specifically, the study seeks to explore how preservice teachers' participation in directed university…

  18. Explorations in Teaching Sustainable Design: A Studio Experience in Interior Design/Architecture

    ERIC Educational Resources Information Center

    Gurel, Meltem O.

    2010-01-01

    This article argues that a design studio can be a dynamic medium to explore the creative potential of the complexity of sustainability from its technological to social ends. The study seeks to determine the impact of an interior design/architecture studio experience that was initiated to teach diverse meanings of sustainability and to engage the…

  19. Generic vs. Modality-Specific Competencies for K-12 Online and Blended Teaching

    ERIC Educational Resources Information Center

    Pulham, Emily B.; Graham, Charles R.; Short, Cecil R.

    2018-01-01

    Although research has explored teacher competencies in K-12 blended and online learning, it has not specified which competencies are appropriate to an online or digital medium, which refer to blending in-person with online experiences, or which are generic--applicable in any teaching modality. This article explores selected K-12 online and blended…

  20. Herpin effective media resonant underlayers and resonant overlayer designs for ultra-high NA interference lithography.

    PubMed

    Bourke, Levi; Blaikie, Richard J

    2017-12-01

    Dielectric waveguide resonant underlayers are employed in ultra-high NA interference photolithography to effectively double the depth of field. Generally a single high refractive index waveguiding layer is employed. Here multilayer Herpin effective medium methods are explored to develop equivalent multilayer waveguiding layers. Herpin equivalent resonant underlayers are shown to be suitable replacements provided at least one layer within the Herpin trilayer supports propagating fields. In addition, a method of increasing the intensity incident upon the photoresist using resonant overlayers is also developed. This method is shown to greatly enhance the intensity within the photoresist making the use of thicker, safer, non-absorbing, low refractive index matching liquids potentially suitable for large-scale applications.

  1. Inhibitory Effect of Algal Extracts on Mycelial Growth of the Tomato-Wilt Pathogen, Fusarium oxysporum f. sp. lycopersici

    PubMed Central

    Kim, Jiyoung

    2008-01-01

    The present study was undertaken to explore the inhibitory effect of cyanobacterial extracts of Nostoc commune FA-103 against the tomato-wilt pathogen, Fusarium oxysporum f. sp. lycopersici. In an optimal medium, cell growth, antifungal activity, and antifungal compound production could be increased 2.7-fold, 4.1-fold, and 13.4-fold, respectively. A crude algal extract had a similar effect as mancozeb at the recommended dose, both in laboratory and pot tests. In vitro and in vivo fungal growth, spore sporulation and fungal infection of wilt pathogen in tomato seeds were significantly inhibited by cyanobacterial extracts. Nostoc commune FA-103 extracts have potential for the suppression of Fusarium oxysporum f. sp. lycopersici. PMID:23997634

  2. Three- α particle correlations in quasi-projectile decay in 12C + 24Mg collisions at 35A MeV

    NASA Astrophysics Data System (ADS)

    Quattrocchi, L.; Acosta, L.; Amorini, F.; Anzalone, A.; Auditore, L.; Berceanu, I.; Cardella, G.; Chbihi, A.; De Filippo, E.; De Luca, S.; Dell'Aquila, D.; Francalanza, L.; Gnoffo, B.; Grzeszczuk, A.; Lanzalone, G.; Lombardo, I.; Martel, I.; Martorana, N. S.; Minniti, T.; Norella, S.; Pagano, A.; Pagano, E. V.; Papa, M.; Pirrone, S.; Politi, G.; Porto, F.; Rizzo, F.; Rosato, E.; Russotto, P.; Trifirò, A.; Trimarchi, M.; Verde, G.; Veselsky, M.; Vigilante, M.

    2017-11-01

    Two and multi particle correlations have been studied in peripheral 12C + 24Mg collisions at 35A MeV with CHIMERA 4 π multi detector, in order to explore resonances produced in light nuclei. Correlations techniques have become a tool to explore nuclear structure properties but also to evaluate the competition between simultaneous and sequential channels in decay of light isotopes. The exploration of features such as branching ratios with respect to different decay channels (sequential vs. simultaneous) could provide information on in-medium effects on nuclear structure properties, an important perspective for research on the nuclear interaction. The performed experiment is preliminary to further studies to be performed by coupling of CHIMERA to FARCOS (Femtoscope ARray for COrrelations and Spectroscopy, FARCOS TDR available at https://drive.google.com/file/d/0B5CgGWz8LpOOc3pGTWdOcDBoWFE) array devoted to measurements of two and multi particle correlations with high energy and angular resolutions.

  3. Interplay of single particle and collective response in molecular dynamics simulation of dusty plasma system

    NASA Astrophysics Data System (ADS)

    Maity, Srimanta; Das, Amita; Kumar, Sandeep; Tiwari, Sanat Kumar

    2018-04-01

    The collective response of the plasma medium is well known and has been explored extensively in the context of dusty plasma medium. On the other hand, the individual particle response associated with the collisional character giving rise to the dissipative phenomena has not been explored adequately. In this paper, two-dimensional molecular dynamics simulation of dust particles interacting via Yukawa potential has been considered. It has been shown that disturbances induced in a dust crystal elicit both collective and single particle responses. Generation of a few particles moving at speeds considerably higher than acoustic and/or shock speed (excited by the external disturbance) is observed. This is an indication of a single particle response. Furthermore, as these individual energetic particles propagate, the dust crystal is observed to crack along their path. Initially when the energy is high, these particles generate secondary energetic particles by the collisional scattering process. However, ultimately as these particles slow down they excite a collective response in the dust medium at secondary locations in a region which is undisturbed by the primary external disturbance. The condition when the cracking of the crystal stops and collective excitations get initiated has been identified quantitatively. The trailing collective primary disturbances would thus often encounter a disturbed medium with secondary and tertiary collective perturbations, thereby suffering significant modification in its propagation. It is thus clear that there is an interesting interplay (other than mere dissipation) between the single particle and collective response which governs the dynamics of any disturbance introduced in the medium.

  4. Study of breakup and transfer of weakly bound nucleus 6Li to explore the low energy reaction dynamics

    NASA Astrophysics Data System (ADS)

    Zhang, G. L.; Zhang, G. X.; Hu, S. P.; Zhang, H. Q.; Gomes, P. R. S.; Lubian, J.; Guo, C. L.; Wu, X. G.; Yang, J. C.; Zheng, Y.; Li, C. B.; He, C. Y.; Zhong, J.; Li, G. S.; Yao, Y. J.; Guo, M. F.; Sun, H. B.; Valiente-Dobòn, J. J.; Goasduff, A.; Siciliano, M.; Galtarosa, F.; Francesco, R.; Testov, D.; Mengoni, D.; Bazzacco, D.; John, P. R.; Qu, W. W.; Wang, F.; Zheng, L.; Yu, L.; Chen, Q. M.; Luo, P. W.; Li, H. W.; Wu, Y. H.; Zhou, W. K.; Zhu, B. J.; Li, E. T.; Hao, X.

    2017-11-01

    Investigation of the breakup and transfer effect of weakly bound nuclei on the fusion process has been an interesting research topic in the past several years. However, owing to the low intensities of the presently available radioactive ion beam (RIB), it is difficult to clearly explore the reaction mechanisms of nuclear systems with unstable nuclei. In comparison with RIB, the beam intensities of stable weakly bound nuclei such as 6,7Li and 9Be, which have significant breakup probability, are orders of magnitude higher. Precise fusion measurements have already been performed with those stable weakly bound nuclei, and the effect of breakup of those nuclei on the fusion process has been extensively studied. Those nuclei indicated large production cross sections for particles other than the α + x breakup. The particles are originated from non-capture breakup (NCBU), incomplete fusion (ICF) and transfer processes. However, the conclusion of reaction dynamics was not clear and has the contradiction. In our previous experiments we have performed 6Li+96Zr and 154Sm at HI-13 Tandem accelerator of China Institute of Atomic Energy (CIAE) by using HPGe array. It is shown that there is a small complete fusion (CF) suppression on medium-mass target nucleus 96Zr different from about 35% suppression on heavier target nucleus 154Sm at near-barrier energies. It seems that the CF suppression factor depends on the charge of target nuclei. We also observed one neutron transfer process. However, the experimental data are scarce for medium-mass target nuclei. In order to have a proper understanding of the influence of breakup and transfer of weakly bound projectiles on the fusion process, we performed the 6Li+89Y experiment with incident energies of 22 MeV and 34 MeV on Galileo array in cooperation with Si-ball EUCLIDES at Legnaro National Laboratory (LNL) in Italy. Using particle-particle and particle-γ coincidences, the different reaction mechanisms can be clearly explored.

  5. Finite element computation of multi-physical micropolar transport phenomena from an inclined moving plate in porous media

    NASA Astrophysics Data System (ADS)

    Shamshuddin, MD.; Anwar Bég, O.; Sunder Ram, M.; Kadir, A.

    2018-02-01

    Non-Newtonian flows arise in numerous industrial transport processes including materials fabrication systems. Micropolar theory offers an excellent mechanism for exploring the fluid dynamics of new non-Newtonian materials which possess internal microstructure. Magnetic fields may also be used for controlling electrically-conducting polymeric flows. To explore numerical simulation of transport in rheological materials processing, in the current paper, a finite element computational solution is presented for magnetohydrodynamic, incompressible, dissipative, radiative and chemically-reacting micropolar fluid flow, heat and mass transfer adjacent to an inclined porous plate embedded in a saturated homogenous porous medium. Heat generation/absorption effects are included. Rosseland's diffusion approximation is used to describe the radiative heat flux in the energy equation. A Darcy model is employed to simulate drag effects in the porous medium. The governing transport equations are rendered into non-dimensional form under the assumption of low Reynolds number and also low magnetic Reynolds number. Using a Galerkin formulation with a weighted residual scheme, finite element solutions are presented to the boundary value problem. The influence of plate inclination, Eringen coupling number, radiation-conduction number, heat absorption/generation parameter, chemical reaction parameter, plate moving velocity parameter, magnetic parameter, thermal Grashof number, species (solutal) Grashof number, permeability parameter, Eckert number on linear velocity, micro-rotation, temperature and concentration profiles. Furthermore, the influence of selected thermo-physical parameters on friction factor, surface heat transfer and mass transfer rate is also tabulated. The finite element solutions are verified with solutions from several limiting cases in the literature. Interesting features in the flow are identified and interpreted.

  6. Knowledge work productivity effect on quality of knowledge work in software development process in SME

    NASA Astrophysics Data System (ADS)

    Yusoff, Mohd Zairol; Mahmuddin, Massudi; Ahmad, Mazida

    2016-08-01

    Knowledge and skill are necessary to develop the capability of knowledge workers. However, there is very little understanding of what the necessary knowledge work (KW) is, and how they influence the quality of knowledge work or knowledge work productivity (KWP) in software development process, including that in small and medium-sized (SME) enterprise. The SME constitutes a major part of the economy and it has been relatively unsuccessful in developing KWP. Accordingly, this paper seeks to explore the influencing dimensions of KWP that effect on the quality of KW in SME environment. First, based on the analysis of the existing literatures, the key characteristics of KW productivity are defined. Second, the conceptual model is proposed, which explores the dimensions of the KWP and its quality. This study analyses data collected from 150 respondents (based on [1], who involve in SME in Malaysia and validates the models by using structural equation modeling (SEM). The results provide an analysis of the effect of KWP on the quality of KW and business success, and have a significant relevance for both research and practice in the SME

  7. Hypoxic-Preconditioned Bone Marrow Stem Cell Medium Significantly Improves Outcome After Retinal Ischemia in Rats

    PubMed Central

    Roth, Steven; Dreixler, John C.; Mathew, Biji; Balyasnikova, Irina; Mann, Jacob R.; Boddapati, Venkat; Xue, Lai; Lesniak, Maciej S.

    2016-01-01

    Purpose We have previously demonstrated the protective effect of bone marrow stem cell (BMSC)-conditioned medium in retinal ischemic injury. We hypothesized here that hypoxic preconditioning of stem cells significantly enhances the neuroprotective effect of the conditioned medium and thereby augments the protective effect in ischemic retina. Methods Rats were subjected to retinal ischemia by increasing intraocular pressure to 130 to 135 mm Hg for 55 minutes. Hypoxic-preconditioned, hypoxic unconditioned, or normoxic medium was injected into the vitreous 24 hours after ischemia ended. Recovery was assessed 7 days after injections by comparing electroretinography measurements, histologic examination, and apoptosis (TUNEL, terminal deoxynucleotidyl transferase–mediated dUTP nick end labeling assay). To compare proteins secreted into the medium in the groups and the effect of hypoxic exposure, we used rat cytokine arrays. Results Eyes injected with hypoxic BMSC–conditioned medium 24 hours after ischemia demonstrated significantly enhanced return of retinal function, decreased retinal ganglion cell layer loss, and attenuated apoptosis compared to those administered normoxic or hypoxic unconditioned medium. Hypoxic-preconditioned medium had 21 significantly increased protein levels compared to normoxic medium. Conclusions The medium from hypoxic-preconditioned BMSCs robustly restored retinal function and prevented cell loss after ischemia when injected 24 hours after ischemia. The protective effect was even more pronounced than in our previous studies of normoxic conditioned medium. Prosurvival signals triggered by the secretome may play a role in this neuroprotective effect. PMID:27367588

  8. Association Between Socio-Demographic Background and Self-Esteem of University Students.

    PubMed

    Haq, Muhammad Ahsan Ul

    2016-12-01

    The purpose of this study was to scrutinize self-esteem of university students and explore association of self-esteem with academic achievement, gender and other factors. A sample of 346 students was selected from Punjab University, Lahore Pakistan. Rosenberg self-esteem scale with demographic variables was used for data collection. Besides descriptive statistics, binary logistic regression and t test were used for analysing the data. Significant gender difference was observed, self-esteem was significantly higher in males than females. Logistic regression indicates that age, medium of instruction, family income, student monthly expenditures, GPA and area of residence has direct effect on self-esteem; while number of siblings showed an inverse effect.

  9. Terahertz time-domain measurement of non-Drude conductivity in silver nanowire thin films for transparent electrode applications

    NASA Astrophysics Data System (ADS)

    Kim, Jaeseok; Maeng, Inhee; Jung, Jongwook; Song, Hyunjoon; Son, Joo-Hiuk; Kim, Kilsuk; Lee, Jaeik; Kim, Chul-Hong; Chae, Geesung; Jun, Myungchul; Hwang, YongKee; Jeong Lee, Su; Myoung, Jae-Min; Choi, Hyunyong

    2013-01-01

    We have investigated the complex conductivity of silver nanowire thin films using terahertz time-domain spectroscopy. Maxwell-Garnett effective medium theory, which accounts for the effective complex conductivity of silver nanowires, is presented in detail theoretically and experimentally. The conductivity of nanowires exhibits a characteristic non-Drude response in which the applied terahertz field is polarized in the longitudinal nanowire direction. The non-Drude responses of the silver nanowires are explained by the Gans approximation and the Drude-Smith model, and both agree well with the experimental data. Our results provide a basis for further explorations of charge carrier dynamics in nanowire-based transparent electrode applications.

  10. Magnesium Hall Thruster

    NASA Technical Reports Server (NTRS)

    Szabo, James J.

    2015-01-01

    This Phase II project is developing a magnesium (Mg) Hall effect thruster system that would open the door for in situ resource utilization (ISRU)-based solar system exploration. Magnesium is light and easy to ionize. For a Mars- Earth transfer, the propellant mass savings with respect to a xenon Hall effect thruster (HET) system are enormous. Magnesium also can be combusted in a rocket with carbon dioxide (CO2) or water (H2O), enabling a multimode propulsion system with propellant sharing and ISRU. In the near term, CO2 and H2O would be collected in situ on Mars or the moon. In the far term, Mg itself would be collected from Martian and lunar regolith. In Phase I, an integrated, medium-power (1- to 3-kW) Mg HET system was developed and tested. Controlled, steady operation at constant voltage and power was demonstrated. Preliminary measurements indicate a specific impulse (Isp) greater than 4,000 s was achieved at a discharge potential of 400 V. The feasibility of delivering fluidized Mg powder to a medium- or high-power thruster also was demonstrated. Phase II of the project evaluated the performance of an integrated, highpower Mg Hall thruster system in a relevant space environment. Researchers improved the medium power thruster system and characterized it in detail. Researchers also designed and built a high-power (8- to 20-kW) Mg HET. A fluidized powder feed system supporting the high-power thruster was built and delivered to Busek Company, Inc.

  11. Enhancing absorption in coated semiconductor nanowire/nanorod core-shell arrays using active host matrices

    NASA Astrophysics Data System (ADS)

    Jule, Leta; Dejene, Francis; Roro, Kittessa

    2016-12-01

    In the present work, we investigated theoretically and experimentally the interaction of radiation field phenomena interacting with arrays of nanowire/nanorod core-shell embedded in active host matrices. The optical properties of composites are explored including the case when the absorption of propagating wave by dissipative component is completely compensated by amplification in active (lasing) medium. On the basis of more elaborated modeling approach and extended effective medium theory, the effective polarizability and the refractive index of electromagnetic mode dispersion of the core-shell nanowire arrays are derived. ZnS(shell)-coated by sulphidation process on ZnO(shell) nanorod arrays grown on (100) silicon substrate by chemical bath deposition (CBD) has been used for theoretical comparison. Compared with the bare ZnO nanorods, ZnS-coated core/shell nanorods exhibit a strongly reduced ultraviolet (UV) emission and a dramatically enhanced deep level (DL) emission. Obviously, the UV and DL emission peaks are attributed to the emissions of ZnO nanorods within ZnO/ZnS core/shell nanorods. The reduction of UV emission after ZnS coating seems to agree with the charge separation mechanism of type-II band alignment that holes transfer from the core to shell, which would quench the UV emission to a certain extent. Our theoretical calculations and numerical simulation demonstrate that the use of active host (amplifying) medium to compensate absorption at metallic inclusions. Moreover the core-shell nanorod/nanowire arrays create the opportunity for broad band absorption and light harvesting applications.

  12. Effect of starch and amylase on the expression of amylase-binding protein A in Streptococcus gordonii

    PubMed Central

    Nikitkova, A.E.; Haase, E.M.; Scannapieco, F.A.

    2012-01-01

    SUMMARY Streptococcus gordonii is a common oral commensal bacterial species in tooth biofilm (dental plaque) and specifically binds to salivary amylase through the surface exposed amylase-binding protein A (AbpA). When S. gordonii cells are pretreated with amylase, amylase bound to AbpA facilitates growth with starch as a primary nutrition source. The goal of this study was to explore possible regulatory effects of starch, starch metabolites and amylase on the expression of S. gordonii AbpA. An amylase ligand-binding assay was used to assess the expression of AbpA in culture supernatants and on bacterial cells from S. gordonii grown in defined medium supplemented with 1% starch, 0.5 mg ml−1 amylase, with starch and amylase together, or with various linear malto-oligosaccharides. Transcription of abpA was determined by reverse transcription quantitative polymerase chain reaction. AbpA was not detectable in culture supernatants containing either starch alone or amylase alone. In contrast, the amount of AbpA was notably increased when starch and amylase were both present in the medium. The expression of abpA was significantly increased (P < 0.05) following 40 min of incubation in defined medium supplemented with starch and amylase. Similar results were obtained in the presence of maltose and other short-chain malto-oligosacchrides. These results suggest that the products of starch hydrolysis produced from the action of salivary α-amylase, particularly maltose and maltotriose, regulate AbpA expression in S. gordonii. PMID:22759313

  13. [Isolation, purification and primary culture of rat pancreatic beta-cells].

    PubMed

    Liu, Yu-Pu; Lü, Qing-Guo; Tong, Nan-Wei

    2009-01-01

    To isolate and purify rat pancreatic beta-cells and to explore the best conditions for the primary culture of the pancreatic beta-cells in vitro. The pancreas of Norman Wistar rats were digested by collagenase V. The islets were purified by mesh sieve. The activity of the islets was stimulated by different concentrations of glucose and detected by dithizone dye. The purified islets were put into RPMI-1640 nutritive medium for culture overnight. The cultured islets were digested again with trypsin and DNAase to obtain the suspension containing single pancreatic cells. The beta-cells were separated and purified in a fluorescence-activated cell sorter (FACS) in the medium containing 2.8 mmol/L glucose. The purified beta-cells were identified by immunohistochemistry and glucose stimulating test. Ham's F-10 with different concentrations of glucose and 3-Isobutyl-1-methylxanthine (IBMX) were used as nutritive medium for the primary cell culture for 24 hours. The best conditions for the culture were identified. An average of 550 +/- 90 islets with fine activities were obtained per rat. The purification with FACS obtained about 5688 beta-cells per rat, with a recovery rate of (93.69 +/- 1.26)% and a purity of (85.5 +/- 1.24)%. A concentration of 10.0 mmol/L and 16.0 mmol/L glucose in primary culture for 24 hours produced the highest survival rates of beta-cells, but IBMX did not increase the survival rates of beta-cells. FACS is effective in purifying pancreatic beta-cells from the suspension with a medium containing 2.8 mmol/L glucose. Pancreatic beta-cells maintain relatively high activities in Ham's F-10 medium containing 10.0-16.0 mmol/L glucose in primary culture.

  14. Linear solutions to metamaterial volume hologram design using a variational approach.

    PubMed

    Marks, Daniel L; Smith, David R

    2018-04-01

    Multiplex volume holograms are conventionally constructed by the repeated exposure of a photosensitive medium to a sequence of external fields, each field typically being the superposition of a reference wave that reconstructs the hologram and the other being a desired signal wave. Because there are no sources of radiation internal to the hologram, the pattern of material modulation is limited to the solutions to Helmholtz's equation in the medium. If the three-dimensional structure of the medium could be engineered at each point rather than limited to the patterns produced by standing waves, more versatile structures may result that can overcome the typical limitations to hologram dynamic range imposed by sequentially superimposing holograms. Metamaterial structures and other synthetic electromagnetic materials offer the possibility of achieving high medium contrast engineered at the subwavelength scale. By posing the multiplex volume holography problem as a linear medium design problem, we explore the potential improvements that such engineered synthetic media may provide over conventional multiplex volume holograms.

  15. "We Are Not as They Think about Us": Exploring Omani EFL Learners' "Selves" in Digital Social Spaces

    ERIC Educational Resources Information Center

    Little, Sabine; Al Wahaibi, Suad

    2017-01-01

    This paper reports a research study of Omani EFL learners' motivation to engage in social technologies through the medium of English, adopting Dörnyei's L2 Motivational Self System as the main theoretical framework, whilst exploring other emergent context-sensitive motivational driving forces. The purpose of the research study was to explore…

  16. Cis and Trans Isomerization in Cyclic Alkenes: A Topic for Discovery Using the Results of Molecular Modeling

    ERIC Educational Resources Information Center

    Barrows, Susan E.; Eberlein, Thomas H.

    2004-01-01

    Activities in which students explore the fundamental reasons behind the unusual instability of the trans isomers in medium-sized cycloalkenes by using the results of molecular modeling are described. Exercises have been proposed to explore the structures of cycloheptene and cyclooctene by Hehre and others which would be helpful to disabuse…

  17. Exploring the Politics of Differential Resource Allocation: Implications for Policy Design and Leadership Practice

    ERIC Educational Resources Information Center

    Halverson, Thomas J.; Plecki, Margaret L.

    2015-01-01

    This qualitative case study explores the political and leadership challenges imbedded within the implementation of a district-wide resource reallocation policy. Based on a two-year study of a medium-sized district's efforts to address changing demographics of families in the district and a widening achievement gap, we draw upon concepts from…

  18. "Reflecting Forward" on the Digital in Multidirectional Memory-Work between Canada and South Africa

    ERIC Educational Resources Information Center

    Strong-Wilson, Teresa; Mitchell, Claudia; Morrison,, Connie; Radford,, Linda; Pithouse-Morgan, Kathleen

    2014-01-01

    We explore the place that the digital can occupy in teachers' pedagogical practices around social justice and especially how memory-work can deepen and enhance teacher practices. Like Walter Benjamin, we see memory as being a medium for exploring the past and where the digital provides greater opportunities for teachers to work productively across…

  19. Room temperature storage of mouse epididymal spermatozoa: exploration of factors affecting sperm survival.

    PubMed

    Sato, Masahiro; Ishikawa, Aki

    2004-05-01

    To explore optimal conditions for in vitro sperm survival, we examined the effects of several media used for murine egg culture and in vitro fertilization (IVF; including M16, M2, PB1, TYH, and CZB) on motility of murine spermatozoa stored at 22 degrees C under paraffin oil. Of media tested, M2 medium, that had been adjusted to pH 7.2 by adding N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES), was found to be the best. Addition of various concentrations of HEPES to TYH did not improve sperm survival, suggesting that HEPES (and probably neutral pH) do not enhance survival of murine sperm. Since M16 has higher amounts of bicarbonate than M2 (25 mM versus 4.15 mM), four variations of M16 media containing 4.15, 8.30, 16.60, or 33.20 mM bicarbonate were prepared and tested. The modified M16 media with 4.15-16.60 mM bicarbonate yielded good sperm survival (comparable to M2 medium), while relatively high concentrations of bicarbonate (ranging from 16.60 to 33.20 mM) were deleterious to isolated sperm, suggesting the need for a minimum level of residual bicarbonate. However, the mechanism by which the lifespan of spermatozoa is extended remains unknown. The in vitro fertilizing abilities of spermatozoa left in M2 medium for 1, 3, and 5 days at 22 degrees C were 52.5, 21.8, and 7.0%, respectively, when the cleavage rate to the two-cell stage was examined. Transfer of two-cell embryos produced in vitro with spermatozoa stored for 1, 3, and 5 days at 22 degrees C resulted in production of fetuses with efficiencies of 42.5, 23.4, and 12.5%, respectively, which were lower than that of embryos derived from in vitro fertilization with fresh spermatozoa (68.1%). In conclusion, spermatozoa kept in M2 medium for up to 5 days at 22 degrees C can fertilize oocytes.

  20. TEMPEST: Twin Electric Magnetospheric Probes Exploring on Spiral Trajectories--A Proposal to the Medium Class Explorer Program

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The objective of the Twin Electric Magnetospheric Probes Exploring on Spiral Trajectories (TEMPEST) mission is to understand the nature and causes of magnetic storm conditions in the magnetosphere whether they be manifested classically in the buildup of the ring current, or (as recently discovered) by storms of relativistic electrons that cause the deep dielectric charging responsible for disabling satellites in synchronous orbit, or by the release of energy into the auroral ionosphere and the plasma sheet during substorms.

  1. Analyzing educational university students' conceptions through smartphone-based PDEODE*E tasks on magnetic field in several mediums

    NASA Astrophysics Data System (ADS)

    Zulfikar, Aldi; Girsang, Denni Yulius; Saepuzaman, Duden; Samsudin, Achmad

    2017-05-01

    Conceptual understanding is one of the most important aspects in the study of Physics because of it useful to understand principles behind certain phenomenon which happened. An innovative method was needed to strengthen and enhance student's conceptual understanding, especially regarding the abstract subject such as magnetic field. For this reason, worksheet and exploration sheet based on PDEODE*E (Predict, Discuss, Explain, Observe, Discuss, Explore, and Explain) that uses Gauss Meter application as the smartphone technology has been designed to answer the problem. The magnetic field strength in different mediums is the physics subject which covered in this research. The research was conducted with the aim to know how effective smartphone technology-based PDEODE*E could be implemented as a physics learning strategy. The result of this research shows that students could show improvements in conceptual understanding that shown by the conclusion that was constructed during the learning process. Based on this result, PDEODE*E could become a solution to strengthen students' conceptual understanding regarding physics subject, especially those that requires abstract thinking. This result also has shown that the application ofsmartphone technology could be used to support physics learning processes in the classroom, such as Gauss Meter in this research which used to measure the magnetic field, Light Meter which could be used in the concept of light, and Harmonicity Meter for the context of the sound wave.

  2. Heat and mass transfer analysis of unsteady MHD nanofluid flow through a channel with moving porous walls and medium

    NASA Astrophysics Data System (ADS)

    Zubair Akbar, Muhammad; Ashraf, Muhammad; Farooq Iqbal, Muhammad; Ali, Kashif

    2016-04-01

    The paper presents the numerical study of heat and mass transfer analysis in a viscous unsteady MHD nanofluid flow through a channel with porous walls and medium in the presence of metallic nanoparticles. The two cases for effective thermal conductivity are discussed in the analysis through H-C model. The impacts of the governing parameters on the flow, heat and mass transfer aspects of the issue are talked about. Under the patronage of small values of permeable Reynolds number and relaxation/contraction parameter, we locate that, when wall contraction is together with suction, flow turning is encouraged close to the wall where the boundary layer is shaped. On the other hand, when the wall relaxation is coupled with injection, the flow adjacent to the porous walls decreased. The outcome of the exploration may be beneficial for applications of biotechnology. Numerical solutions for the velocity, heat and mass transfer rate at the boundary are obtained and analyzed.

  3. Ram Pressure Stripping of Galaxy JO201

    NASA Astrophysics Data System (ADS)

    Zhong, Greta; Tonnesen, Stephanie; Jaffé, Yara; Bellhouse, Callum; Bianca Poggianti

    2017-01-01

    Despite the discovery of the morphology-density relation more than 30 years ago, the process driving the evolution of spiral galaxies into S0s in clusters is still widely debated. Ram pressure stripping--the removal of a galaxy's interstellar medium by the pressure of the intracluster medium through which it orbits--may help explain galactic evolution and quenching in clusters. MUSE (Multi Unit Spectroscopic Explorer) observational data of galaxy JO201 in cluster Abell 85 reveal it to be a jellyfish galaxy--one with an H-alpha emitting gas tail on only one side. We model the possible orbits for this galaxy, constrained by the cluster mass profile, line of sight velocity, and projected distance from the cluster center. Using Enzo, an adaptive mesh refinement hydrodynamics code, we simulate effects of ram pressure on this galaxy for a range of possible orbits. We present comparisons of both the morphology and velocity structure of our simulated galaxy to the observations of H-alpha emission.

  4. Exploration of a mechanism for the production of highly unsaturated fatty acids in Scenedesmus sp. at low temperature grown on oil crop residue based medium.

    PubMed

    Lu, Qian; Li, Jun; Wang, Jinghan; Li, Kun; Li, Jingjing; Han, Pei; Chen, Paul; Zhou, Wenguang

    2017-11-01

    The ability of algae to produce lipids comprising of unsaturated fatty acids varies with strains and culture conditions. This study investigates the effect of temperature on the production of unsaturated fatty acids in Scenedesmus sp. grown on oil crop residue based medium. At low temperature (10°C), synthesis of lipids compromising of high contents of unsaturated fatty acids took place primarily in the early stage while protein accumulation mainly occurred in the late stage. This stepwise lipid-protein synthesis process was found to be associated with the contents of acetyl-CoA and α-KG in the algal cells. A mechanism was proposed and tested through simulation experiments which quantified the carbon flux allocation in algal cells at different cultivation stages. It is concluded that low culture temperature such as 10°C is suitable for the production of lipids comprising of unsaturated fatty acids. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Statistical approach for the enhanced production of cold-active β-galactosidase from Thalassospira frigidphilosprofundus: a novel marine psychrophile from deep waters of Bay of Bengal.

    PubMed

    Pulicherla, K K; Kumar, P Suresh; Manideep, K; Rekha, V P B; Ghosh, Mrinmoy; Sambasiva Rao, K R S

    2013-01-01

    In the present investigation Thalassospira frigidphilosprofundus, a novel species from the deep waters of the Bay of Bengal, was explored for the production of cold-active β-galactosidase by submerged fermentation using marine broth medium as the basal medium. Effects of various medium constituents, namely, carbon, nitrogen source, pH, and temperature, were investigated using a conventional one-factor-at-a-time method. It was found that lactose, yeast extract, and bactopeptones are the most influential components for β-galactosidase production. Under optimal conditions, the production of β-galactosidase was found to be 3,864 U/mL at 20 ± 2°C, pH 6.5 ± 0.2, after 48 hr of incubation. β-Galactosidase production was further optimized by the Taguchi orthogonal array design of experiments and the central composite rotatable design (CCRD) of response surface methodology. Under optimal experimental conditions the cold-active β-galactosidase enzyme production from Thalassospira frigidphilosprofundus was enhanced from 3,864 U/mL to 10,657 U/mL, which is almost three times higher than the cold-active β-galactosidase production from the well-reported psychrophile Pseudoalteromonas haloplanktis.

  6. Corrosion of Mg alloy AZ91D in the presence of living cells.

    PubMed

    Seuss, F; Seuss, S; Turhan, M C; Fabry, B; Virtanen, S

    2011-11-01

    Mg and Mg alloys are of interest for biodegradable implants as they readily corrode in biological fluids, and dissolved Mg ions are nontoxic. Even though it is well known that Mg dissolution leads to pH increase in the surroundings, the effect of the corrosion-induced alkalization on the biological environment has not been studied in detail. We therefore explored the interactions between corrosion-induced pH increase and cell growth on Mg alloy AZ91D surface. Cell adhesion and spreading on the alloy surface is unimpeded initially. However, with time a large fraction of cells de-adhere. We attribute this to the observed increase of the pH in the cell culture medium in the process of alloy dissolution. Cytotoxicity tests with HeLa cells grown on glass surfaces confirm that cell death increases with increasing alkalinity of the cell culture medium. We also show that a the cells that adhere on the Mg alloy surface act as a corrosion-blocking surface layer. In consequence, a slower pH increase in the medium takes place when the alloy surface is covered with cells. Electrochemical impedance spectroscopy measurements (EIS) verify that a cell layer slows down the corrosion process. 2011 Wiley Periodicals, Inc.

  7. Inverse scattering theory: Inverse scattering series method for one dimensional non-compact support potential

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

    Yao, Jie, E-mail: yjie2@uh.edu; Lesage, Anne-Cécile; Hussain, Fazle

    2014-12-15

    The reversion of the Born-Neumann series of the Lippmann-Schwinger equation is one of the standard ways to solve the inverse acoustic scattering problem. One limitation of the current inversion methods based on the reversion of the Born-Neumann series is that the velocity potential should have compact support. However, this assumption cannot be satisfied in certain cases, especially in seismic inversion. Based on the idea of distorted wave scattering, we explore an inverse scattering method for velocity potentials without compact support. The strategy is to decompose the actual medium as a known single interface reference medium, which has the same asymptoticmore » form as the actual medium and a perturbative scattering potential with compact support. After introducing the method to calculate the Green’s function for the known reference potential, the inverse scattering series and Volterra inverse scattering series are derived for the perturbative potential. Analytical and numerical examples demonstrate the feasibility and effectiveness of this method. Besides, to ensure stability of the numerical computation, the Lanczos averaging method is employed as a filter to reduce the Gibbs oscillations for the truncated discrete inverse Fourier transform of each order. Our method provides a rigorous mathematical framework for inverse acoustic scattering with a non-compact support velocity potential.« less

  8. [Anti-HBV effects of genetically engineered replication-defective HBV with combined expression of antisense RNA and dominant negative mutants of core protein and construction of first-generation packaging cell line for HBV vector].

    PubMed

    Sun, Dian Xing; Hu, Da Rong; Wu, Guang Hui; Hu, Xue Ling; Li, Juan; Fan, Gong Ren

    2002-08-01

    To explore the possibility of using HBV as a gene delivery vector, and to test the anti-HBV effects by intracellular combined expression of antisense RNA and dominant negative mutants of core protein. Full length of mutant HBV genome, which expresses core-partial P fusion protein and/or antisense RNA, was transfected into HepG2.2.15 cell lines. Positive clones were selected and mixed in respective groups with hygromycin in the culture medium. HBsAg and HBeAg, which exist in the culture medium, were tested by ELISA method. Intracellular HBc related HBV DNA was examined by dot blot hybridization. The existence of recombinant HBV virion in the culture medium was examined by PCR. Free of packaging signal, HBV genome, which express the HBV structural proteins including core, pol and preS/S proteins, was inserted into pCI-neo vector. HepG2 cell lines were employed to transfect with the construct. G418 selection was done at the concentration of 400mug/ml in the culture medium. The G418-resistant clones with the best expression of HBsAg and HBcAg were theoretically considered as packaging cell lines and propagated under the same conditions. It was transfected with plasmid pMEP-CPAS and then selected with G418 and hygromycin in the culture medium. The existence of recombinant HBV virion in the culture medium was examined by PCR. The mean inhibitory rates of HBsAg were 2.74% 3.83%, 40.08 2.05% (t=35.5, P<0.01), 66.54% 4.45% (t=42.3, P<0.01), and 73.68% 5.07% (t=51.9, P<0.01) in group 2.2.15-pMEP4, 2.2.15-CP, 2.2.15-SAS, and 2.2.15-CPAS, respectively. The mean inhibitory rates of HBeAg were 4.46% 4.25%, 52.86% 1.32% (t=36.2, P<0.01), 26.36% 1.69% (t=22.3, P<0.01), and 59.28% 2.10% (t=39.0, P<0.01), respectively. The inhibitory rates of HBc related HBV DNA were 0, 82.0%, 59.9%, and 96.6%, respectively. Recombinant HB virion was detectable in the culture medium of all the three treatment groups. G418-resistant HBV packaging cell line, which harbored an HBV mutant whose packaging signal had been deleted, was generated. Expression of HBsAg and HBcAg was detectable. Transfected with plasmid pMEP-CPAS, it was found to secrete recombinant HB virion and no wild-type HBV was detectable in the culture medium. It has stronger anti-HBV effects by combined expression of antisense RNA and dominant negative mutants than by individual expression of them. With the help of wild-type HBV, the modified HBV genome can form and secret HBV like particles, which provides evidence that the antiviral gene will be hepatotropic expression and the antiviral effects will be amplified. The packaging cell line can provide packaging for replication-defective HBV, but with low efficiency.

  9. [Some peculiar features of liquid supply to the root medium of plants growing in microgravity

    NASA Technical Reports Server (NTRS)

    Podol'skii, I. G.; Sychev, V. N.; Levinskikh, M. A.; Strugov, O. M.; Bingham, G. E.; Salisbury, F. B. (Principal Investigator)

    1998-01-01

    Sixteen point probes monitored moisture level in the root medium of the wheat plants grown in greenhouse SVET on the MIR/NASA space science program. The article outlines types of water migration in the absence of gravity. Hydrophysical characteristics of perspective root media have been explored. Results of the water supply monitoring and control in the course of experiment are reported. The authors put forward porous root media to facilitate water migration and aeration.

  10. [Effects of environmental stress on secondary metabolites of Aspergillus ochraceus LCJ11-102 associated with the coral Dichotella gemmacea].

    PubMed

    Zhou, Yalin; Wang, Yi; Liu, Peipei; Wang, Zhiying; Zhu, Weiming

    2010-08-01

    To explore the secondary metabolites of fungus Aspergillus ochraceus LCJ11-102 associated with the coral Dichotella gemmacea under environmental stress and to obtain characteristic compounds with biological activities. A nutrient-deprived culture medium (biomimetic culture) and a high salt culture medium were used for fermentation. Fingerprints of HPLC of the fermentation broth were used to investigate the diversity of secondary metabolites. Compounds were isolated by column chromatography on silica gel, Sephadex LH-20, and preparative HPLC. Their structures were identified by spectroscopic analyses and the modified Mosher's method. Different secondary metabolites were produced by A. ochraceus LCJ11-102 under two different culture conditions. (R)-mellein (1), (5,6-trans, 8,9-threo-) -9-chloro-8-hydroxy-8, 9-deoxyaspyrone (2), (5,6-erythro-, 8,9-threo-) -9-chloro-8-hydroxy-8, 9-deoxyasperlactone (3), and (5S, 6R, 9S)-dihydroaspyrone (4) were identified from the biomimetic cultures, and R (+) -semi-vioxanthin (5) was identified from the high salt cultures, respectively. Environmental stress obviously induces microbes to produce different secondary metabolites. And biomimetic culture is an effective approach to obtain active chloro compounds from marine microorganisms.

  11. General formulation of characteristic time for persistent chemicals in a multimedia environment

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

    Bennett, D.H.; McKone, T.E.; Kastenberg, W.E.

    1999-02-01

    A simple yet representative method for determining the characteristic time a persistent organic pollutant remains in a multimedia environment is presented. The characteristic time is an important attribute for assessing long-term health and ecological impacts of a chemical. Calculating the characteristic time requires information on decay rates in multiple environmental media as well as the proportion of mass in each environmental medium. The authors explore the premise that using a steady-state distribution of the mass in the environment provides a means to calculate a representative estimate of the characteristic time while maintaining a simple formulation. Calculating the steady-state mass distributionmore » incorporates the effect of advective transport and nonequilibrium effects resulting from the source terms. Using several chemicals, they calculate and compare the characteristic time in a representative multimedia environment for dynamic, steady-state, and equilibrium multimedia models, and also for a single medium model. They demonstrate that formulating the characteristic time based on the steady-state mass distribution in the environment closely approximates the dynamic characteristic time for a range of chemicals and thus can be used in decisions regarding chemical use in the environment.« less

  12. Expression of Listeria monocytogenes key virulence genes during growth in liquid medium, on rocket and melon at 4, 10 and 30 °C.

    PubMed

    Hadjilouka, Agni; Molfeta, Christina; Panagiotopoulou, Olga; Paramithiotis, Spiros; Mataragas, Marios; Drosinos, Eleftherios H

    2016-05-01

    The aim of the present study was to assess the expression of key virulence genes, during growth of a Listeria monocytogenes isolate in liquid medium, on melon and rocket at different temperatures and time. For that purpose, BHI broth, rocket and melon were inoculated at 7.0-7.5 log CFU mL(-1) or g(-1)and stored at 4, 10 and 30 °C. Sampling took place upon inoculation and after 0.5, 6 and 24 h of incubation. The RNA was stabilized and the expression of hly, plcA, plcB, sigB, inlA, inlB, inlC, inlJ, lmo2672 and lmo2470 was assessed by RT-qPCR. The results obtained were summarized into two observations; the first one referring to the interactive effect of incubation temperature and type of substrate and the second one to the effect of time on gene expression. Regarding the latter, nearly all genes were regulated upon inoculation and exhibited differential expression in the subsequent sampling times indicating the existence of additional regulatory mechanisms yet to be explored. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Protein Corona Prevents TiO2 Phototoxicity

    PubMed Central

    Garvas, Maja; Testen, Anze; Umek, Polona; Gloter, Alexandre; Koklic, Tilen; Strancar, Janez

    2015-01-01

    Background & Aim TiO2 nanoparticles have generally low toxicity in the in vitro systems although some toxicity is expected to originate in the TiO2-associated photo-generated radical production, which can however be modulated by the radical trapping ability of the serum proteins. To explore the role of serum proteins in the phototoxicity of the TiO2 nanoparticles we measure viability of the exposed cells depending on the nanoparticle and serum protein concentrations. Methods & Results Fluorescence and spin trapping EPR spectroscopy reveal that the ratio between the nanoparticle and protein concentrations determines the amount of the nanoparticles’ surface which is not covered by the serum proteins and is proportional to the amount of photo-induced radicals. Phototoxicity thus becomes substantial only at the protein concentration being too low to completely coat the nanotubes’ surface. Conclusion These results imply that TiO2 nanoparticles should be applied with ligands such as proteins when phototoxic effects are not desired - for example in cosmetics industry. On the other hand, the nanoparticles should be used in serum free medium or any other ligand free medium, when phototoxic effects are desired – as for efficient photodynamic cancer therapy. PMID:26083725

  14. The impact of fiscal austerity on suicide mortality: Evidence across the 'Eurozone periphery'.

    PubMed

    Antonakakis, Nikolaos; Collins, Alan

    2015-11-01

    While linkages between some macroeconomic phenomena and suicides in some countries have been explored, only two studies, hitherto, have established a causal relationship between fiscal austerity and suicide, albeit in a single country. The aim of this study is to provide the first systematic multiple-country evidence of a causal relationship of fiscal austerity on time-, gender-, and age-specific suicide mortality across five Eurozone peripheral countries, namely Greece, Ireland, Italy, Portugal and Spain over the period 1968-2012, while controlling for various socioeconomic differences. The impact of fiscal adjustments is found to be gender-, age- and time-specific. Specifically, fiscal austerity has short-, medium- and long-run suicide increasing effects on the male population in the 65-89 age group. A 1% reduction in government spending is associated with a 1.38%, 2.42% and 3.32% increase in the short-, medium- and long-run, respectively, of male suicides rates in the 65-89 age group in the Eurozone periphery. These results are highly robust to alternative measures of fiscal austerity. Improved labour market institutions help mitigate the negative effects of fiscal austerity on suicide mortality. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Application of Plackett-Burman Experimental Design for Lipase Production by Aspergillus niger Using Shea Butter Cake

    PubMed Central

    Salihu, Aliyu; Bala, Muntari; Bala, Shuaibu M.

    2013-01-01

    Plackett-Burman design was used to efficiently select important medium components affecting the lipase production by Aspergillus niger using shea butter cake as the main substrate. Out of the eleven medium components screened, six comprising of sucrose, (NH4)2SO4, Na2HPO4, MgSO4, Tween-80, and olive oil were found to contribute positively to the overall lipase production with a maximum production of 3.35 U/g. Influence of tween-80 on lipase production was investigated, and 1.0% (v/w) of tween-80 resulted in maximum lipase production of 6.10 U/g. Thus, the statistical approach employed in this study allows for rapid identification of important medium parameters affecting the lipase production, and further statistical optimization of medium and process parameters can be explored using response surface methodology. PMID:25937979

  16. Application of Plackett-Burman Experimental Design for Lipase Production by Aspergillus niger Using Shea Butter Cake.

    PubMed

    Salihu, Aliyu; Bala, Muntari; Bala, Shuaibu M

    2013-01-01

    Plackett-Burman design was used to efficiently select important medium components affecting the lipase production by Aspergillus niger using shea butter cake as the main substrate. Out of the eleven medium components screened, six comprising of sucrose, (NH4)2SO4, Na2HPO4, MgSO4, Tween-80, and olive oil were found to contribute positively to the overall lipase production with a maximum production of 3.35 U/g. Influence of tween-80 on lipase production was investigated, and 1.0% (v/w) of tween-80 resulted in maximum lipase production of 6.10 U/g. Thus, the statistical approach employed in this study allows for rapid identification of important medium parameters affecting the lipase production, and further statistical optimization of medium and process parameters can be explored using response surface methodology.

  17. Virtual Reality: An Instructional Medium for Visual-Spatial Tasks.

    ERIC Educational Resources Information Center

    Regian, J. Wesley; And Others

    1992-01-01

    Describes an empirical exploration of the instructional potential of virtual reality as an interface for simulation-based training. Shows that subjects learned spatial-procedural and spatial-navigational skills in virtual reality. (SR)

  18. Effect of culture medium on toxic effect of ZnO nanoparticles to freshwater microalgae

    NASA Astrophysics Data System (ADS)

    Aravantinou, Andriana F.; Tsarpali, Vasiliki; Dailianis, Stefanos; Manariotis, Ioannis D.

    2014-05-01

    The widely use of nanoparticles (NPs) in many products, is increasing over time. The release of NPs into the environment may affect ecosystems, and therefore it is essential to study their impact on aquatic organisms. The aim of this work was to investigate the effect of zinc oxide (ZnO) NPs on microalgae, cultured in different mediums. Chlorococcum sp. and Scenedesmus rubescens were used as freshwater microalgae model species in order to investigate the toxic effects of ZnO NPs. Microalgae species exposed to ZnO NPs concentrations varying from 0.081 to 810 mg/L for different periods of time (24 to 96 h) and two different culture mediums. The aggregation level and particle size distribution of NPs were also determined during the experiments. The experimental results revealed significant differences on algae growth rates depending on the selected culture medium. Specifically, the toxic effect of ZnO NPs in Chlorococcum sp. was higher in cultures with 1/3N BG-11 medium than in BBM medium, despite the fact that the dissolved zinc concentration was higher in BBM medium. On the other hand, Scenedesmus rubescens exhibited the exact opposite behavior, with the highest toxic effect in cultures with BBM medium. Both species growth was significantly affected by the exposure time, the NPs concentrations, and mainly the culture medium.

  19. When EFL Teachers Perform L2 and L1 in the Classroom, What Happens to Their Sense of Self?

    ERIC Educational Resources Information Center

    Forman, Ross

    2015-01-01

    We often hear from speakers of L2 that they "feel different" when communicating through the medium of an additional language. While there has been much exploration of L2-­mediated identity development in naturalistic settings, there is very little conducted within the instructed learning environment of EFL. The present study explores how…

  20. Let's Tweet in Chinese! Exploring How Learners of Chinese as a Foreign Language Self-Direct Their Use of Microblogging to Learn Chinese

    ERIC Educational Resources Information Center

    Hsiao, Ya Ping; Broeder, Peter

    2014-01-01

    Twitter is becoming increasingly popular as a medium for language learning. This study explores self-directed learning via social interactions that use Twitter as an interactive learning environment. The participants in this study were thirty university students of Chinese as a foreign language at levels 1 and 2 of the "Hanyu Shuiping…

  1. Fluxgate magnetometers for outer planets exploration

    NASA Technical Reports Server (NTRS)

    Acuna, M. H.

    1974-01-01

    The exploration of the interplanetary medium and the magnetospheres of the outer planets requires the implementation of magnetic field measuring instrumentation with wide dynamic range, high stability, and reliability. The fluxgate magnetometers developed for the Pioneer 11 and Mariner-Jupiter-Saturn missions are presented. These instruments cover the range of .01 nT to 2 million nT with optimum performance characteristics and low power consumption.

  2. Medium-mediated effects increase cell killing in a human keratinocyte cell line exposed to solar-simulated radiation.

    PubMed

    Maguire, Alanna; Morrissey, Brian; Walsh, James E; Lyng, Fiona M

    2011-01-01

    The objective of this study was to investigate whether cell culture medium is a biologically relevant exposure medium that can be employed in non-ionising photobiological investigations. The effect of solar-simulated irradiation on cell culture medium and its ability to elicit cell death was studied. The role of reactive oxygen species (ROS), cell secreted factors, and the contribution of individual components of the medium were investigated. Cell death was found to be primarily mediated through the formation of ROS via riboflavin photosensitisation and degradation in the cell culture medium. Phenol red was found to significantly reduce the cell killing ability of riboflavin. Exposures in riboflavin-free medium resulted in significantly increased cell survival compared to identical exposures in riboflavin containing medium. This study has shown that solar radiation toxicity is augmented by cell culture medium due to the presence of riboflavin. Results suggest that exposures performed in phenol red-free medium may serve to increase phototoxic effects if riboflavin is present. Riboflavin-free media is recommended for solar radiation investigations to eliminate concerns regarding riboflavin photosensitisation and nutrient deprivation.

  3. A Practical, Affordable Cryogenic Propellant Depot Based on ULA's Flight Experience

    NASA Technical Reports Server (NTRS)

    Kutter, Bernard F.; Zegler, Frank; O'Neil, Gary; Pitchford, Brian

    2008-01-01

    Mankind is embarking on the next step in the journey of human exploration. We are returning to the moon and eventually moving to Mars and beyond. The current Exploration architecture seeks a balance between the need for a robust infrastructure on the lunar surface, and the performance limitations of Ares I and V. The ability to refuel or top-off propellant tanks from orbital propellant depots offers NASA the opportunity to cost effectively and reliably satisfy these opposing requirements. The ability to cache large orbital quantities of propellant is also an enabling capability for missions to Mars and beyond. This paper describes an option for a propellant depot that enables orbital refueling supporting Exploration, national security, science and other space endeavors. This proposed concept is launched using a single EELV medium class rocket and thus does not require any orbital assembly. The propellant depot provides cryogenic propellant storage that utilizes flight proven technologies augmented with technologies currently under development. The propellant depot system, propellant management, flight experience, and key technologies are also discussed. Options for refueling the propellant depot along with an overview of Exploration architecture impacts are also presented.

  4. Application of Effective Medium Theory to the Three-Dimensional Heterogeneity of Mantle Anisotropy

    NASA Astrophysics Data System (ADS)

    Song, X.; Jordan, T. H.

    2015-12-01

    A self-consistent theory for the effective elastic parameters of stochastic media with small-scale 3D heterogeneities has been developed using a 2nd-order Born approximation to the scattered wavefield (T. H. Jordan, GJI, in press). Here we apply the theory to assess how small-scale variations in the local anisotropy of the upper mantle affect seismic wave propagation. We formulate a anisotropic model in which the local elastic properties are specified by a constant stiffness tensor with hexagonal symmetry of arbitrary orientation. This orientation is guided by a Gaussian random vector field with transversely isotropic (TI) statistics. If the outer scale of the statistical variability is small compared to a wavelength, then the effective seismic velocities are TI and depend on two parameters, a horizontal-to-vertical orientation ratio ξ and a horizontal-to-vertical aspect ratio, η. If ξ = 1, the symmetry axis is isotropically distributed; if ξ < 1, it is vertical biased (bipolar distribution), and if ξ > 1, it is horizontally biased (girdle distribution). If η = 1, the heterogeneity is geometrically isotropic; as η à∞, the medium becomes a horizontal stochastic laminate; as η à0, the medium becomes a vertical stochastic bundle. Using stiffness tensors constrained by laboratory measurements of mantle xenoliths, we explore the dependence of the effective P and S velocities on ξ and η. The effective velocities are strongly controlled by the orientation ratio ξ; e.g., if the hexagonal symmetry axis of the local anisotropy is the fast direction of propagation, then vPH > vPV and vSH > vSV for ξ > 1. A more surprising result is the 2nd-order insensitivity of the velocities to the heterogeneity aspect ratio η. Consequently, the geometrical anisotropy of upper-mantle heterogeneity significantly enhances seismic-wave anisotropy only through local variations in the Voigt-averaged velocities, which depend primarily on rock composition and not deformation history.

  5. Effects of exercise and manual therapy on pain associated with hip osteoarthritis: a systematic review and meta-analysis.

    PubMed

    Beumer, Lucy; Wong, Jennie; Warden, Stuart J; Kemp, Joanne L; Foster, Paul; Crossley, Kay M

    2016-04-01

    To explore the effects of exercise (water-based or land-based) and/or manual therapies on pain in adults with clinically and/or radiographically diagnosed hip osteoarthritis (OA). A systematic review and meta-analysis was performed, with patient reported pain assessed using a visual analogue scale (VAS) or the Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain subscale. Data were grouped by follow-up time (0-3 months=short term; 4-12 months=medium term and; >12 months=long term), and standardised mean differences (SMD) with 95% CIs were used to establish intervention effect sizes. Study quality was assessed using modified PEDro scores. 19 trials were included. Four studies showed short-term benefits favouring water-based exercise over minimal control using the WOMAC pain subscale (SMD -0.53, 95% CI -0.96 to -0.10). Six studies supported a short-term benefit of land-based exercise compared to minimal control on VAS assessed pain (SMD -0.49, 95% CI -0.70 to -0.29). There were no medium (SMD -0.23, 95% CI -0.48 to 0.03) or long (SMD -0.22, 95% CI -0.51 to 0.06) term benefits of exercise therapy, or benefit of combining exercise therapy with manual therapy (SMD -0.38, 95% CI -0.88 to 0.13) when compared to minimal control. Best available evidence indicates that exercise therapy (whether land-based or water-based) is more effective than minimal control in managing pain associated with hip OA in the short term. Larger high-quality RCTs are needed to establish the effectiveness of exercise and manual therapies in the medium and long term. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  6. Cross-platform learning: on the nature of children's learning from multiple media platforms.

    PubMed

    Fisch, Shalom M

    2013-01-01

    It is increasingly common for an educational media project to span several media platforms (e.g., TV, Web, hands-on materials), assuming that the benefits of learning from multiple media extend beyond those gained from one medium alone. Yet research typically has investigated learning from a single medium in isolation. This paper reviews several recent studies to explore cross-platform learning (i.e., learning from combined use of multiple media platforms) and how such learning compares to learning from one medium. The paper discusses unique benefits of cross-platform learning, a theoretical mechanism to explain how these benefits might arise, and questions for future research in this emerging field. Copyright © 2013 Wiley Periodicals, Inc., A Wiley Company.

  7. A Lesson in Values.

    ERIC Educational Resources Information Center

    Deahl, Patricia Herz

    2002-01-01

    Describes a seventh-grade art project used to help students explore different types of art mediums. Focuses on each of the four parts of the project: (1) pencil; (2) pen and ink; (3) paint; and (4) collage. (CMK)

  8. Parental Perceptions, Experiences, and Desires of Music Therapy

    PubMed Central

    Kong, Ha-Kyung; Karahalios, Karrie

    2016-01-01

    Music therapy (MT) is a therapeutic practice where a therapist uses music to enhance the life quality for their patients. Children have an innate enjoyment of music, making music an effective medium for exploring their potential. In this study, we explore the parental perception of MT through an online survey. Contrary to the public perception that MT only addresses emotional needs, 47 out of 59 parents reported seeing improvements in other areas including behavioral, cognitive, linguistic, and social changes. All but one parent indicated that they would recommend MT to others. The survey results further revealed that even parents of children participating in MT had misconceptions regarding MT, which we describe in the paper. Parents reported inaccessibility and cost as other major limitations surrounding MT adoption. We conclude by discussing how technology solutions could mitigate issues with definition, distance, and cost, while maintaining the benefits of MT. PMID:28269946

  9. Parental Perceptions, Experiences, and Desires of Music Therapy.

    PubMed

    Kong, Ha-Kyung; Karahalios, Karrie

    2016-01-01

    Music therapy (MT) is a therapeutic practice where a therapist uses music to enhance the life quality for their patients. Children have an innate enjoyment of music, making music an effective medium for exploring their potential. In this study, we explore the parental perception of MT through an online survey. Contrary to the public perception that MT only addresses emotional needs, 47 out of 59 parents reported seeing improvements in other areas including behavioral, cognitive, linguistic, and social changes. All but one parent indicated that they would recommend MT to others. The survey results further revealed that even parents of children participating in MT had misconceptions regarding MT, which we describe in the paper. Parents reported inaccessibility and cost as other major limitations surrounding MT adoption. We conclude by discussing how technology solutions could mitigate issues with definition, distance, and cost, while maintaining the benefits of MT.

  10. Lung cells support osteosarcoma cell migration and survival.

    PubMed

    Yu, Shibing; Fourman, Mitchell Stephen; Mahjoub, Adel; Mandell, Jonathan Brendan; Crasto, Jared Anthony; Greco, Nicholas Giuseppe; Weiss, Kurt Richard

    2017-01-25

    Osteosarcoma (OS) is the most common primary bone tumor, with a propensity to metastasize to the lungs. Five-year survival for metastatic OS is below 30%, and has not improved for several decades despite the introduction of multi-agent chemotherapy. Understanding OS cell migration to the lungs requires an evaluation of the lung microenvironment. Here we utilized an in vitro lung cell and OS cell co-culture model to explore the interactions between OS and lung cells, hypothesizing that lung cells would promote OS cell migration and survival. The impact of a novel anti-OS chemotherapy on OS migration and survival in the lung microenvironment was also examined. Three human OS cell lines (SJSA-1, Saos-2, U-2) and two human lung cell lines (HULEC-5a, MRC-5) were cultured according to American Type Culture Collection recommendations. Human lung cell lines were cultured in growth medium for 72 h to create conditioned media. OS proliferation was evaluated in lung co-culture and conditioned media microenvironment, with a murine fibroblast cell line (NIH-3 T3) in fresh growth medium as controls. Migration and invasion were measured using a real-time cell analysis system. Real-time PCR was utilized to probe for Aldehyde Dehydrogenase (ALDH1) expression. Osteosarcoma cells were also transduced with a lentivirus encoding for GFP to permit morphologic analysis with fluorescence microscopy. The anti-OS efficacy of Disulfiram, an ALDH-inhibitor previously shown to inhibit OS cell proliferation and metastasis in vitro, was evaluated in each microenvironment. Lung-cell conditioned medium promoted osteosarcoma cell migration, with a significantly higher attractive effect on all three osteosarcoma cell lines compared to basic growth medium, 10% serum containing medium, and NIH-3 T3 conditioned medium (p <0.05). Lung cell conditioned medium induced cell morphologic changes, as demonstrated with GFP-labeled cells. OS cells cultured in lung cell conditioned medium had increased alkaline phosphatase staining. Lung endothelial HULEC-5a cells are attractants for OS cell migration, proliferation, and survival. The SJSA-1 osteosarcoma cell line demonstrated greater metastatic potential than Saos-2 and U-2 cells. ALDH appears to be involved in the interaction between lung and OS cells, and ALP may be a valuable biomarker for monitoring functional OS changes during metastasis.

  11. The effect of different levels of realism of context learning on the prescribing competencies of medical students during the clinical clerkship in internal medicine: an exploratory study.

    PubMed

    Tichelaar, Jelle; van Kan, Coen; van Unen, Robert J; Schneider, Anton J; van Agtmael, Michiel A; de Vries, Theo P G M; Richir, Milan C

    2015-02-01

    The aim of this study is to evaluate the effect of different levels of realism of context learning on the prescribing competencies of medical students during the clinical clerkship in internal medicine. Between 2001 and 2007, 164 medical students took part in the prospective explorative study during their clinical clerkship in internal medicine at the VU University Medical Center, Amsterdam, The Netherlands. In a fixed order, each student had to formulate a treatment plan for a real patient in three situations of increasing realism: a minimal level (studying a patient record), medium level (preparing for a therapeutic consultation), and optimal level (preparing for and performing a therapeutic consultation with the patient). In comparison to studying a patient record (minimal context level), preparing a therapeutic consultation (medium context) improved four of the six steps of the WHO six-step plan. Preparing and performing a therapeutic consultation with a real patient (optimal context) further improved three essential prescribing competencies, namely checking for contraindications and interactions, prescription writing, and instructions to the patient. The results of this first explorative study suggest that enrichment of the learning context (responsibility for patient care) might be an important factor to improve the training of rational prescribing skills of medical students during their clinical clerkship in internal medicine. Clinical (pharmacology) teachers should be aware that seemingly small adaptations in the learning context of prescribing training during clinical clerkships (i.e., with or without involvement with and responsibility for patient care) may have relatively large impact on the development of prescribing competencies of our future doctors.

  12. Resonant line transfer in a fog: using Lyman-alpha to probe tiny structures in atomic gas

    NASA Astrophysics Data System (ADS)

    Gronke, Max; Dijkstra, Mark; McCourt, Michael; Peng Oh, S.

    2017-11-01

    Motivated by observational and theoretical work that suggest very small-scale (≲ 1 pc) structure in the circumgalactic medium of galaxies and in other environments, we study Lyman-α (Lyα) radiative transfer in an extremely clumpy medium with many clouds of neutral gas along the line of sight. While previous studies have typically considered radiative transfer through sightlines intercepting ≲ 10 clumps, we explored the limit of a very large number of clumps per sightline (up to fc 1000). Our main finding is that, for covering factors greater than some critical threshold, a multiphase medium behaves similarly to a homogeneous medium in terms of the emergent Lyα spectrum. The value of this threshold depends on both the clump column density and the movement of the clumps. We estimated this threshold analytically and compare our findings to radiative transfer simulations with a range of covering factors, clump column densities, radii, and motions. Our results suggest that (I) the success in fitting observed Lyα spectra using homogeneous "shell models" (and the corresponding failure of multiphase models) hints at the presence of very small-scale structure in neutral gas, which is in agreement within a number of other observations; and (II) the recurrent problems of reproducing realistic line profiles from hydrodynamical simulations may be due to their inability to resolve small-scale structure, which causes simulations to underestimate the effective covering factor of neutral gas clouds. The movie associated to Fig. B.2 is available at http://www.aanda.org

  13. Gender Variance and Sexual Orientation Among Male Spirit Mediums in Myanmar.

    PubMed

    Coleman, Eli; Allen, Mariette Pathy; Ford, Jessie V

    2018-05-01

    This article describes the gender identity, gender expression, and sexual orientation of male spirit mediums in Myanmar. Our analysis is based on ethnographic work, field observation, and 10 semi-structured interviews. These observations were conducted from 2010 to 2015, mostly in Mandalay, with some fieldwork in Yangon and Bagan. The focus of this investigation was specifically on achout (gender variant individuals) who were spirit mediums (nat kadaw). Semi-structured interviews explored the ways that participants understood their gender identity, gender expression, and sexuality in relation to their work as spirit mediums and broader social life. Myanmar remains quite a homophobic and transphobic culture but is undergoing rapid economic and social change. Therefore, it provides an interesting context to study how safe spaces are produced for sexual/gender minorities amidst broader social change. We find that, through the animistic belief structure, there is a growing space for gender nonconforming people, gender variant, and same-sex-oriented individuals (achout) to neutralize their stigmatized status and attain a level of respect and economic advantage. Their ability to become nat kadaw (mediums of spirits) mitigates or trumps their stigmatized status.

  14. Food price policies improve diet quality while increasing socioeconomic inequalities in nutrition

    PubMed Central

    2014-01-01

    Background Prices are an important determinant of food choices. Consequently, food price policies (subsidies and/or taxes) are proposed to improve the nutritional quality of diets. The aim of the present study was to explore the impact of food price policies on the expenditures and nutritional quality of the food baskets chosen by low- and medium-income households. Methods Experimental economics was used to examine two price manipulations: i) a fruit and vegetable price subsidy named “fruit and vegetables condition”; ii) a healthy-product subsidy coupled with an unhealthy-product tax named “nutrient profile condition”. The nutrient profiling system called SAIN,LIM was used. This system classifies each individual food according to its overall nutritional quality which then allows for a food item to be taxed or subsidized. Women from low- (n = 95) and medium-incomes (n = 33) selected a daily food basket, first, at current prices and then at manipulated prices. The redistributive effects of experimental conditions were assessed by comparing the extent of savings induced by subsidies and of costs generated by the tax on the two income groups. Energy density (kcal/100 g), free sugars (% energy) and the mean adequacy ratio (MAR) were used as nutritional quality indicators. Results At baseline (before price manipulations), low-income women selected less expensive and less healthy baskets than medium-income ones. After price manipulations expenditures for both income group decreased significantly, whereas, the nutritional quality improved (energy density decreased, the MAR increased). Additionally, the redistributive effects were less favourable for low-income women and their nutritional quality improvements from baseline were significantly lower. Conclusion Low-income women derived fewer financial and nutritional benefits from implemented food subsidies and taxes than medium-income women. This outcome suggests that food price policies may improve diet quality while increasing socio-economic inequalities in nutrition. PMID:24886414

  15. A one dimensional numerical approach for computing the eigenmodes of elastic waves in buried pipelines

    NASA Astrophysics Data System (ADS)

    Duan, Wenbo; Kirby, Ray; Mudge, Peter; Gan, Tat-Hean

    2016-12-01

    Ultrasonic guided waves are often used in the detection of defects in oil and gas pipelines. It is common for these pipelines to be buried underground and this may restrict the length of the pipe that can be successfully tested. This is because acoustic energy travelling along the pipe walls may radiate out into the surrounding medium. Accordingly, it is important to develop a better understanding of the way in which elastic waves propagate along the walls of buried pipes, and so in this article a numerical model is developed that is suitable for computing the eigenmodes for uncoated and coated buried pipes. This is achieved by combining a one dimensional eigensolution based on the semi-analytic finite element (SAFE) method, with a perfectly matched layer (PML) for the infinite medium surrounding the pipe. This article also explores an alternative exponential complex coordinate stretching function for the PML in order to improve solution convergence. It is shown for buried pipelines that accurate solutions may be obtained over the entire frequency range typically used in long range ultrasonic testing (LRUT) using a PML layer with a thickness equal to the pipe wall thickness. This delivers a fast and computationally efficient method and it is shown for pipes buried in sand or soil that relevant eigenmodes can be computed and sorted in less than one second using relatively modest computer hardware. The method is also used to find eigenmodes for a buried pipe coated with the viscoelastic material bitumen. It was recently observed in the literature that a viscoelastic coating may effectively isolate particular eigenmodes so that energy does not radiate from these modes into the surrounding [elastic] medium. A similar effect is also observed in this article and it is shown that this occurs even for a relatively thin layer of bitumen, and when the shear impedance of the coating material is larger than that of the surrounding medium.

  16. Food price policies improve diet quality while increasing socioeconomic inequalities in nutrition.

    PubMed

    Darmon, Nicole; Lacroix, Anne; Muller, Laurent; Ruffieux, Bernard

    2014-05-20

    Prices are an important determinant of food choices. Consequently, food price policies (subsidies and/or taxes) are proposed to improve the nutritional quality of diets. The aim of the present study was to explore the impact of food price policies on the expenditures and nutritional quality of the food baskets chosen by low- and medium-income households. Experimental economics was used to examine two price manipulations: i) a fruit and vegetable price subsidy named "fruit and vegetables condition"; ii) a healthy-product subsidy coupled with an unhealthy-product tax named "nutrient profile condition". The nutrient profiling system called SAIN,LIM was used. This system classifies each individual food according to its overall nutritional quality which then allows for a food item to be taxed or subsidized. Women from low- (n = 95) and medium-incomes (n = 33) selected a daily food basket, first, at current prices and then at manipulated prices. The redistributive effects of experimental conditions were assessed by comparing the extent of savings induced by subsidies and of costs generated by the tax on the two income groups. Energy density (kcal/100 g), free sugars (% energy) and the mean adequacy ratio (MAR) were used as nutritional quality indicators. At baseline (before price manipulations), low-income women selected less expensive and less healthy baskets than medium-income ones. After price manipulations expenditures for both income group decreased significantly, whereas, the nutritional quality improved (energy density decreased, the MAR increased). Additionally, the redistributive effects were less favourable for low-income women and their nutritional quality improvements from baseline were significantly lower. Low-income women derived fewer financial and nutritional benefits from implemented food subsidies and taxes than medium-income women. This outcome suggests that food price policies may improve diet quality while increasing socio-economic inequalities in nutrition.

  17. Neutrino mixing, oscillations and decoherence in astrophysics and cosmology

    NASA Astrophysics Data System (ADS)

    Ho, Chiu Man

    2007-08-01

    This thesis focuses on a finite-temperature field-theoretical treatment of neutrino oscillations in hot and dense media. By implementing the methods of real-time non-equilibrium field theory, we study the dynamics of neutrino mixing, oscillations, decoherence and relaxation in astrophysical and cosmological environments. We first study neutrino oscillations in the early universe in the temperature regime prior to the epoch of Big Bang Nucleosynthesis (BBN). The dispersion relations and mixing angles in the medium are found to be helicity-dependent, and a resonance like the Mikheyev-Smirnov- Wolfenstein (MSW) effect is realized. The oscillation time scales are found to be longer near a resonance and shorter for off-resonance high-energy neutrinos. We then investigate the space-time propagation of neutrino wave-packets just before BBN. A phenomenon of " frozen coherence " is found to occur if the longitudinal dispersion catches up with the progressive separation between the mass eigenstates, before the coherence time limit has been reached. However, the transverse dispersion occurs at a much shorter scale than all other possible time scales in the medium, resulting in a large suppression in the transition probabilities from electron-neutrino to muon-neutrino. We also explore the possibility of charged lepton mixing as a consequence of neutrino mixing in the early Universe. We find that charged leptons, like electrons and muons, can mix and oscillate resonantly if there is a large lepton asymmetry in the neutrino sector. We study sterile neutrino production in the early Universe via active-sterile oscillations. We provide a quantum field theoretical reassessment of the quantum Zeno suppression on the active-to-sterile transition probability and its time average. We determine the complete conditions for quantum Zeno suppression. Finally, we examine the interplay between neutrino mixing, oscillations and equilibration in a thermal medium, and the corresponding non-equilibrium dynamics. The equilibrium density matrix is found to be nearly diagonal in the basis of eigenstates of an effective Hamiltonian that includes self-energy corrections in the medium.

  18. Building Your Own Regression Model

    ERIC Educational Resources Information Center

    Horton, Robert, M.; Phillips, Vicki; Kenelly, John

    2004-01-01

    Spreadsheets to explore regression with an algebra 2 class in a medium-sized rural high school are presented. The use of spreadsheets can help students develop sophisticated understanding of mathematical models and use them to describe real-world phenomena.

  19. Arsenolite: a quasi-hydrostatic solid pressure-transmitting medium.

    PubMed

    Sans, J A; Manjón, F J; Popescu, C; Muñoz, A; Rodríguez-Hernández, P; Jordá, J L; Rey, F

    2016-11-30

    This study reports the experimental characterization of the hydrostatic properties of arsenolite (As4O6), a molecular solid which is one of the softest minerals in the absence of hydrogen bonding. The high compressibility of arsenolite and its stability up to 15 GPa have been proved by x-ray diffraction measurements, and the progressive loss of hydrostaticity with increasing pressure up to 20 GPa has been monitored by ruby photoluminescence. Arsenolite has been found to exhibit hydrostatic behavior up to 2.5 GPa and a quasi-hydrostatic behavior up to 10 GPa at room temperature. This result opens the way to explore other molecular solids as possible quasi-hydrostatic pressure-transmitting media. The validity of arsenolite as an insulating, stable, non-penetrating and quasi-hydrostatic medium is explored by the study of the x-ray diffraction of zeolite ITQ-29 at high pressure.

  20. "I wanted to communicate my feelings freely": a descriptive study of creative responses to enhance reflection in palliative medicine education.

    PubMed

    McBain, Lynn; Donnelly, Sinéad; Hilder, Jo; O'Leary, Clare; McKinlay, Eileen

    2015-10-23

    The recent growth of arts and humanities in medical education shows recognition that these disciplines can facilitate a breadth of thinking and result in personal and professional growth. However creative work can be a challenge to incorporate into a busy curriculum. Offering the option of creative media as a way of reflecting is an example of how this can occur. This study aimed to examine the medical student response to being given this option to explore a visit to a patient in a hospice. This was a mainly qualitative study. In the 2012 academic programme, the class of 86 students were given the option of using a creative medium to explore their responses to both the visit and their developing communication skills. Students were required to write an accompanying commentary if submitting the creative work option. Sixty-four percent of the class chose a creative medium e.g. poetry, visual art, narrative prose, music. These students were asked to take part in research including completing a short on-line survey and consenting for their creative work and commentaries to be further examined. The creative works were categorised by genre and the commentaries analysed using inductive thematic analysis. Seventeen students completed the on-line survey and fifteen consented to their work being used for this research. Thematic analysis of the student commentaries revealed the following themes: effectiveness for expressing emotion or ideas that are difficult to articulate; engaging and energising quality of the task; time for reflection; flexibility for individual learning styles and therapeutic value. Teaching the art of communicating at end-of-life is challenging especially when it involves patients, and teachers want to ensure students gain as much as possible from the experience. Offering the option to use creative media means that students can choose a medium for reflection that best suits them as individuals and that can enable them to benefit as much as possible from their experience.

  1. Board task performance: An exploration of micro- and macro-level determinants of board effectiveness

    PubMed Central

    Minichilli, Alessandro; Zattoni, Alessandro; Nielsen, Sabina; Huse, Morten

    2012-01-01

    This paper addresses recent calls to narrow the micro–macro gap in management research (Bamberger, 2008), by incorporating a macro-level context variable (country) in exploring micro-level determinants of board effectiveness. Following the integrated model proposed by Forbes and Milliken (1999), we identify three board processes as micro-level determinants of board effectiveness. Specifically, we focus on effort norms, cognitive conflicts and the use of knowledge and skills as determinants of board control and advisory task performance. Further, we consider how two different institutional settings influence board tasks, and how the context moderates the relationship between processes and tasks. Our hypotheses are tested on a survey-based dataset of 535 medium-sized and large industrial firms in Italy and Norway, which are considered to substantially differ along legal and cultural dimensions. The findings show that: (i) Board processes have a larger potential than demographic variables to explain board task performance; (ii) board task performance differs significantly between boards operating in different contexts; and (iii) national context moderates the relationships between board processes and board task performance. Copyright © 2010 John Wiley & Sons, Ltd. PMID:23365485

  2. [Production of shikonin by cell cultures of Lithospermum erythrorhizon].

    PubMed

    Hu, Liyong

    2004-05-01

    To explore cultural conditions of shikonin production by cell cultures of Lithospermum erythrorhizon. Orthogonal design was applied in determination of shikonin within the medium. Flask test was applied in the study of shikonin production by the amount of ventilation. The best medium consisted of 100 mg/L L-phenylalanine, 2 mg/L IAA and 800 mg/L Ca(NO3)2 4H2O. The best amount of ventilation was get by shaken at 150 r/min. This test provided data for producing shikonin by cell cultures of Lithospermum erythrorhizon.

  3. [Qualitative and quantitative determination of amino-2 benzimidazole in aqueous medium by polarography (author's transl)].

    PubMed

    Roche, Y; Cantin, D; Vigier, J; Boucherle, A

    1978-03-01

    Amino-2 Benzimidazole, a residue of the decomposition of some fungicides (Benomyl, Carbendazine, Thiophanate, Methylthiophanate), is measured by polarography in aqueous medium, with a platinium rotating electrode, for the exploration in potentials from +0.5 v to 1.4 v. The best conditions for the quantitative determination are investigated, the study according to pH is performed and the standard curve is given for concentrations from 10(-5) to 10(-3) M/l. The interaction of elementts found in tap water and in aquarium water is also investigated.

  4. Effective-Medium Models for Marine Gas Hydrates, Mallik Revisited

    NASA Astrophysics Data System (ADS)

    Terry, D. A.; Knapp, C. C.; Knapp, J. H.

    2011-12-01

    Hertz-Mindlin type effective-medium dry-rock elastic models have been commonly used for more than three decades in rock physics analysis, and recently have been applied to assessment of marine gas hydrate resources. Comparisons of several effective-medium models with derivative well-log data from the Mackenzie River Valley, Northwest Territories, Canada (i.e. Mallik 2L-38 and 5L-38) were made several years ago as part of a marine gas hydrate joint industry project in the Gulf of Mexico. The matrix/grain supporting model (one of the five models compared) was clearly a better representation of the Mallik data than the other four models (2 cemented sand models; a pore-filling model; and an inclusion model). Even though the matrix/grain supporting model was clearly better, reservations were noted that the compressional velocity of the model was higher than the compressional velocity measured via the sonic logs, and that the shear velocities showed an even greater discrepancy. Over more than thirty years, variations of Hertz-Mindlin type effective medium models have evolved for unconsolidated sediments and here, we briefly review their development. In the past few years, the perfectly smooth grain version of the Hertz-Mindlin type effective-medium model has been favored over the infinitely rough grain version compared in the Gulf of Mexico study. We revisit the data from the Mallik wells to review assertions that effective-medium models with perfectly smooth grains are a better predictor than models with infinitely rough grains. We briefly review three Hertz-Mindlin type effective-medium models, and standardize nomenclature and notation. To calibrate the extended effective-medium model in gas hydrates, we use a well accepted framework for unconsolidated sediments through Hashin-Shtrikman bounds. We implement the previously discussed effective-medium models for saturated sediments with gas hydrates and compute theoretical curves of seismic velocities versus gas hydrate saturation to compare with well log data available from the Canadian gas hydrates research site. By directly comparing the infinitely rough and perfectly smooth grain versions of the Hertz-Mindlin type effective-medium model, we provide additional insight to the discrepancies noted in the Gulf of Mexico study.

  5. Relationship between pH and Medium Dissolved Solids in Terms of Growth and Metabolism of Lactobacilli and Saccharomyces cerevisiae during Ethanol Production

    PubMed Central

    Narendranath, Neelakantam V.; Power, Ronan

    2005-01-01

    The specific growth rates of four species of lactobacilli decreased linearly with increases in the concentration of dissolved solids (sugars) in liquid growth medium. This was most likely due to the osmotic stress exerted by the sugars on the bacteria. The reduction in growth rates corresponded to decreased lactic acid production. Medium pH was another factor studied. As the medium pH decreased from 5.5 to 4.0, there was a reduction in the specific growth rate of lactobacilli and a corresponding decrease in the lactic acid produced. In contrast, medium pH did not have any significant effect on the specific growth rate of yeast at any particular concentration of dissolved solids in the medium. However, medium pH had a significant (P < 0.001) effect on ethanol production. A medium pH of 5.5 resulted in maximal ethanol production in all media with different concentrations of dissolved solids. When the data were analyzed as a 4 (pH levels) by 4 (concentrations of dissolved solids) factorial experiment, there was no synergistic effect (P > 0.2923) observed between pH of the medium and concentration of dissolved solids of the medium in reducing bacterial growth and metabolism. The data suggest that reduction of initial medium pH to 4.0 for the control of lactobacilli during ethanol production is not a good practice as there is a reduction (P < 0.001) in the ethanol produced by the yeast at pH 4.0. Setting the mash (medium) with ≥30% (wt/vol) dissolved solids at a pH of 5.0 to 5.5 will minimize the effects of bacterial contamination and maximize ethanol production by yeast. PMID:15870306

  6. Exploring the Interstellar Medium with SOFIA

    NASA Technical Reports Server (NTRS)

    Erickson, Edwin F.

    2004-01-01

    SOFIA, the Stratospheric Observatory for Infrared Astronomy, is being developed to operate at wavelengths from 0.3 microns to 1.6 mm over a 20 year lifetime. Its 2.5 m effective diameter telescope will be diffraction limited (approximately 8.5 arc seconds FWHM at 100 microns) at wavelengths beyond about 5 microns. Its B747SP aircraft platform will allow coverage of the entire sky and enable observation of ephemeral events. Nine first-generation focal plane instruments are being built, and more will be added later. These attributes assure SOFIA a vital role in future studies of the interstellar medium (ISM), in addition to topics such as the solar system. SOFIA observers will explore the gamut of ISM topics: star formation; the Galactic Center; debris disks; recycling of materials through the stellar life cycle; the origin and evolution of biogenic materials; shock, photodissociation, and photoexcitation physics; gas and grain chemistry. Imaging, spectroscopy, and eventually polarimetry covering much of the infrared spectrum will all be part of SOFIA's arsenal in the attack on these and other important problems. The talk will describe the observatory, its status, its science instruments and anticipated program. SOFIA is a joint program of NASA in the U.S. and DLR in Germany. Broad participation by the international science community in SOFIA observations will be encouraged via annual proposal opportunities and user-friendly tools. Roughly 80% of the observing time will be granted by the U.S. and 20% by Germany. For further information, see http://sofia.arc.nasa.gov.

  7. Environmental Impact Specification for Direct Space Weathering of Kuiper Belt and Oort Cloud Objects

    NASA Technical Reports Server (NTRS)

    Cooper, John F.

    2010-01-01

    The Direct Space Weathering Project of NASA's Outer Planets Research Program addresses specification of the plasma and energetic particle environments for irradiation and surface chemical processing of icy bodies in the outer solar system and the local interstellar medium. Knowledge of the radiation environments is being expanded by ongoing penetration of the twin Voyager spacecraft into the heliosheath boundary region of the outer heliosphere and expected emergence within the next decade into the very local interstellar medium. The Voyager measurements are being supplemented by remote sensing from Earth orbit of energetic neutral atom emission from this boundary region by NASA's Interstellar Boundary Explorer (IBEX). Although the Voyagers long ago passed the region of the Classical Kuiper Belt, the New Horizons spacecraft will encounter Pluto in 2015 and thereafter explore one or more KBOs, meanwhile providing updated measurements of the heliospheric radiation environment in this region. Modeling of ion transport within the heliosphere allows specification of time-integrated irradiation effects while the combination of Voyager and IBEX data supports projection of the in-situ measurements into interstellar space beyond the heliosheath. Transformation of model ion flux distributions into surface sputtering and volume ionization profiles provides a multi-layer perspective for space weathering impact on the affected icy bodies and may account for some aspects of color and compositional diversity. Other important related factors may include surface erosion and gardening by meteoritic impacts and surface renewal by cryovolcanism. Chemical products of space weathering may contribute to energy resources for the latter.

  8. Cranberry derivatives enhance biofilm formation and transiently impair swarming motility of the uropathogen Proteus mirabilis HI4320.

    PubMed

    O'May, Che; Amzallag, Olivier; Bechir, Karim; Tufenkji, Nathalie

    2016-06-01

    Proteus mirabilis is a major cause of catheter-associated urinary tract infection (CAUTI), emphasizing that novel strategies for targeting this bacterium are needed. Potential targets are P. mirabilis surface-associated swarming motility and the propensity of these bacteria to form biofilms that may lead to catheter blockage. We previously showed that the addition of cranberry powder (CP) to lysogeny broth (LB) medium resulted in impaired P. mirabilis swarming motility over short time periods (up to 16 h). Herein, we significantly expanded on those findings by exploring (i) the effects of cranberry derivatives on biofilm formation of P. mirabilis, (ii) whether swarming inhibition occurred transiently or over longer periods more relevant to real infections (∼3 days), (iii) whether swarming was also blocked by commercially available cranberry juices, (iv) whether CP or cranberry juices exhibited effects under natural urine conditions, and (v) the effects of cranberry on medium pH, which is an indirect indicator of urease activity. At short time scales (24 h), CP and commercially available pure cranberry juice impaired swarming motility and repelled actively swarming bacteria in LB medium. Over longer time periods more representative of infections (∼3 days), the capacity of the cranberry material to impair swarming diminished and bacteria would start to migrate across the surface, albeit by exhibiting a different motility phenotype to the regular "bull's-eye" swarming phenotype of P. mirabilis. This bacterium did not swarm on urine agar or LB agar supplemented with urea, suggesting that any potential application of anti-swarming compounds may be better suited to settings external to the urine environment. Anti-swarming effects were confounded by the ability of cranberry products to enhance biofilm formation in both LB and urine conditions. These findings provide key insights into the long-term strategy of targeting P. mirabilis CAUTIs.

  9. Summer temperature increase has distinct effects on the ectomycorrhizal fungal communities of moist tussock and dry tundra in Arctic Alaska.

    PubMed

    Morgado, Luis N; Semenova, Tatiana A; Welker, Jeffrey M; Walker, Marilyn D; Smets, Erik; Geml, József

    2015-02-01

    Arctic regions are experiencing the greatest rates of climate warming on the planet and marked changes have already been observed in terrestrial arctic ecosystems. While most studies have focused on the effects of warming on arctic vegetation and nutrient cycling, little is known about how belowground communities, such as fungi root-associated, respond to warming. Here, we investigate how long-term summer warming affects ectomycorrhizal (ECM) fungal communities. We used Ion Torrent sequencing of the rDNA internal transcribed spacer 2 (ITS2) region to compare ECM fungal communities in plots with and without long-term experimental warming in both dry and moist tussock tundra. Cortinarius was the most OTU-rich genus in the moist tundra, while the most diverse genus in the dry tundra was Tomentella. On the diversity level, in the moist tundra we found significant differences in community composition, and a sharp decrease in the richness of ECM fungi due to warming. On the functional level, our results indicate that warming induces shifts in the extramatrical properties of the communities, where the species with medium-distance exploration type seem to be favored with potential implications for the mobilization of different nutrient pools in the soil. In the dry tundra, neither community richness nor community composition was significantly altered by warming, similar to what had been observed in ECM host plants. There was, however, a marginally significant increase in OTUs identified as ECM fungi with the medium-distance exploration type in the warmed plots. Linking our findings of decreasing richness with previous results of increasing ECM fungal biomass suggests that certain ECM species are favored by warming and may become more abundant, while many other species may go locally extinct due to direct or indirect effects of warming. Such compositional shifts in the community might affect nutrient cycling and soil organic C storage. © 2014 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

  10. Summer temperature increase has distinct effects on the ectomycorrhizal fungal communities of moist tussock and dry tundra in Arctic Alaska

    PubMed Central

    Morgado, Luis N; Semenova, Tatiana A; Welker, Jeffrey M; Walker, Marilyn D; Smets, Erik; Geml, József

    2015-01-01

    Arctic regions are experiencing the greatest rates of climate warming on the planet and marked changes have already been observed in terrestrial arctic ecosystems. While most studies have focused on the effects of warming on arctic vegetation and nutrient cycling, little is known about how belowground communities, such as fungi root-associated, respond to warming. Here, we investigate how long-term summer warming affects ectomycorrhizal (ECM) fungal communities. We used Ion Torrent sequencing of the rDNA internal transcribed spacer 2 (ITS2) region to compare ECM fungal communities in plots with and without long-term experimental warming in both dry and moist tussock tundra. Cortinarius was the most OTU-rich genus in the moist tundra, while the most diverse genus in the dry tundra was Tomentella. On the diversity level, in the moist tundra we found significant differences in community composition, and a sharp decrease in the richness of ECM fungi due to warming. On the functional level, our results indicate that warming induces shifts in the extramatrical properties of the communities, where the species with medium-distance exploration type seem to be favored with potential implications for the mobilization of different nutrient pools in the soil. In the dry tundra, neither community richness nor community composition was significantly altered by warming, similar to what had been observed in ECM host plants. There was, however, a marginally significant increase in OTUs identified as ECM fungi with the medium-distance exploration type in the warmed plots. Linking our findings of decreasing richness with previous results of increasing ECM fungal biomass suggests that certain ECM species are favored by warming and may become more abundant, while many other species may go locally extinct due to direct or indirect effects of warming. Such compositional shifts in the community might affect nutrient cycling and soil organic C storage. PMID:25156129

  11. Super-resolution with a positive epsilon multi-quantum-well super-lens

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

    Bak, A. O.; Giannini, V.; Maier, S. A.

    2013-12-23

    We design an anisotropic and dichroic quantum metamaterial that is able to achieve super-resolution without the need for a negative permittivity. When exploring the parameters of the structure, we take into account the limits of semiconductor fabrication technology based on quantum well stacks. By heavily doping the structure with free electrons, we infer an anisotropic effective medium with a prolate ellipsoid dispersion curve which allows for near-diffractionless propagation of light (similar to an epsilon-near-zero hyperbolic lens). This, coupled with low absorption, allows us to resolve images at the sub-wavelength scale at distances 6 times greater than equivalent natural materials.

  12. A method for converting dose-to-medium to dose-to-tissue in Monte Carlo studies of gold nanoparticle-enhanced radiotherapy

    NASA Astrophysics Data System (ADS)

    Koger, B.; Kirkby, C.

    2016-03-01

    Gold nanoparticles (GNPs) have shown potential in recent years as a means of therapeutic dose enhancement in radiation therapy. However, a major challenge in moving towards clinical implementation is the exact characterisation of the dose enhancement they provide. Monte Carlo studies attempt to explore this property, but they often face computational limitations when examining macroscopic scenarios. In this study, a method of converting dose from macroscopic simulations, where the medium is defined as a mixture containing both gold and tissue components, to a mean dose-to-tissue on a microscopic scale was established. Monte Carlo simulations were run for both explicitly-modeled GNPs in tissue and a homogeneous mixture of tissue and gold. A dose ratio was obtained for the conversion of dose scored in a mixture medium to dose-to-tissue in each case. Dose ratios varied from 0.69 to 1.04 for photon sources and 0.97 to 1.03 for electron sources. The dose ratio is highly dependent on the source energy as well as GNP diameter and concentration, though this effect is less pronounced for electron sources. By appropriately weighting the monoenergetic dose ratios obtained, the dose ratio for any arbitrary spectrum can be determined. This allows complex scenarios to be modeled accurately without explicitly simulating each individual GNP.

  13. Assessment Parameters and Matching between the Sites and Wind Turbines

    NASA Astrophysics Data System (ADS)

    Chermitti, A.; Bencherif, M.; Nakoul, Z.; Bibitriki, N.; Benyoucef, B.

    The objective of this paper is to introduce the assessment parameters of the wind energy production of sites and pairing between the sites and wind turbines. The exploration is made with the wind data gathered at 10 m high is based on the atlas of the wind of Algeria established by the National office of the Meteorology runs 37 stations of measures. The data is used for a feasibility analysis of optimum future utilization of Wind generator potentiality in five promising sites covering a part of landscape types and regions in Algeria. Detailed technical assessment for the ten most promising potential wind sites was made using the capacity factor and the site effectiveness approach. The investigation was performed assuming several models of small, medium and big size wind machines representing different ranges of characteristic speeds and rated power suitable for water pumping and electric supply. The results show that small wind turbines could be installed in some coast region and medium wind turbines could be installed in the high plateau and some desert regions and utilized for water supply and electrical power generation, the sites having an important wind deposit, in high plateau we find Tiaret site's but in the desert there is some sites for example Adrar, Timimoun and In Amenas, in these sites could be installed a medium and big size wind turbines.

  14. Inversion of time-domain induced polarization data based on time-lapse concept

    NASA Astrophysics Data System (ADS)

    Kim, Bitnarae; Nam, Myung Jin; Kim, Hee Joon

    2018-05-01

    Induced polarization (IP) surveys, measuring overvoltage phenomena of the medium, are widely and increasingly performed not only for exploration of mineral resources but also for engineering applications. Among several IP survey methods such as time-domain, frequency-domain and spectral IP surveys, this study introduces a noble inversion method for time-domain IP data to recover the chargeability structure of target medium. The inversion method employs the concept of 4D inversion of time-lapse resistivity data sets, considering the fact that measured voltage in time-domain IP survey is distorted by IP effects to increase from the instantaneous voltage measured at the moment the source current injection starts. Even though the increase is saturated very fast, we can consider the saturated and instantaneous voltages as a time-lapse data set. The 4D inversion method is one of the most powerful method for inverting time-lapse resistivity data sets. Using the developed IP inversion algorithm, we invert not only synthetic but also field IP data to show the effectiveness of the proposed method by comparing the recovered chargeability models with those from linear inversion that was used for the inversion of the field data in a previous study. Numerical results confirm that the proposed inversion method generates reliable chargeability models even though the anomalous bodies have large IP effects.

  15. Tyrosine kinase inhibitor BIBF1120 ameliorates inflammation, angiogenesis and fibrosis in CCl4-induced liver fibrogenesis mouse model

    PubMed Central

    Öztürk Akcora, Büsra; Storm, Gert; Prakash, Jai; Bansal, Ruchi

    2017-01-01

    Hepatic fibrosis, a progressive chronic disease mainly caused by hepatitis viral infections, alcohol abuse or metabolic syndrome leading to liver dysfunction and is the growing cause of mortality worldwide. Tyrosine kinase inhibitor BIBF1120 (Nintedanib) has been evaluated in clinical trials for idiopathic pulmonary fibrosis and advanced Hepatocellular carcinoma, but has not been explored for liver fibrosis yet. In this study, we aimed to investigate the therapeutic effects and mechanism of BIBF1120 in liver fibrogenesis. The effects of BIBF1120 were evaluated in TGFβ-activated mouse 3T3 fibroblasts, LX2 cells, primary human hepatic stellate cells (HSCs) and CCl4-induced liver fibrogenesis mouse model. Fibroblasts-conditioned medium studies were performed to assess the paracrine effects on macrophages and endothelial cells. In-vitro in TGFβ-activated fibroblasts, BIBF1120 significantly inhibited expression of major fibrotic parameters, wound-healing and contractility. In vivo in CCl4-induced acute liver injury model, post-disease BIBF1120 administration significantly attenuated collagen accumulation and HSC activation. Interestingly, BIBF1120 drastically inhibited intrahepatic inflammation and angiogenesis. To further elucidate the mechanism of action, 3T3-conditioned medium studies demonstrated increased 3T3-mediated macrophage chemotaxis and endothelial cells tube formation and activation, which was significantly decreased by BIBF1120. These results suggests that BIBF1120 can be a potential therapeutic approach for the treatment of liver fibrosis. PMID:28291245

  16. Modification of c and n sources for enhanced production of cyclosporin ‘a’ by Aspergillus Terreus

    PubMed Central

    Tanseer, Sundas; Anjum, Tehmina

    2011-01-01

    Most of the studies regarding cyclosporin ‘A’ production through fungi concentrate around Tolypocladium inflatum. This is mainly due to lower reported production of this drug in other fungi. The present study was therefore conducted to explore indigenous isolates of Aspergillus terreus for synthesis of this drug and defining a production medium for obtaining high yield of cyclosporin ‘A’. For this purpose carbon and nitrogen sources were optimized for the selected best strain of A. terreus. Overall results depicted that the best cyclosporin ‘A’ yield from selected Aspergillus terreus (FCBP58) could be obtained by using production medium containing glucose 10% as carbon source and peptone 0.5% as nitrogen source. This modification in production medium enhanced drug synthesis by selected fungi significantly. The production capabilities when compared with biomass of fungi there was found no relationship between the two confirming that the medium modification increased overall drug synthesis powers of the fungi. PMID:24031766

  17. Dissociation of 1P states in hot QCD Medium Using Quasi-Particle Model

    NASA Astrophysics Data System (ADS)

    Nilima, Indrani; Agotiya, Vineet Kumar

    2018-03-01

    We extend the analysis of a very recent work [1] to study the dissociation phenomenon of 1P states of the charmonium and bottomonium spectra (χc and χb) in a hot QCD medium using Quasi-Particle Model. This study employed a medium modified heavy quark potential which has quite different form in the sense that it has a lomg range Coulombic tail in addition to the Yukawa term even above the deconfinement temperature. Then we study the flavor dependence of their binding energies and explore the nature of dissociation temperatures by employing the Quasi-Particle debye mass for pure gluonic and full QCD case. Interestingly, the dissociation temperatures obtained by employing EoS1 and EoS2 with the Γ criterion, is closer to the upper bound of the dissociation temperatures which are obtained by the dissolution of a given quarkonia state by the mean thermal energy of the quasi-partons in the hot QCD/QGP medium.

  18. Effects of neural stem cell media on hypoxic injury in rat hippocampal slice cultures.

    PubMed

    Lee, Na Mi; Chae, Soo Ahn; Lee, Hong Jun

    2017-12-15

    Neonatal hypoxic-ischemic brain injuries cause serious neurological sequelae, yet there is currently no effective treatment for them. We hypothesized that neurotrophic factors released into the medium by stem cells could supply hypoxia-damaged organotypic hippocampal slice cultures with regenerative abilities. We prepared organotypic slice cultures of the hippocampus of 7-day-old Sprague-Dawley rats based on the modified Stoppini method; slices were cultured for 14days in vitro using either Gahwiler's medium (G-medium) or stem cell-conditioned medium (S-medium) as culture medium. At day 14 in vitro, hippocampal slice cultures were exposed to 95% N 2 and 5% CO 2 for 3h to induce hypoxic damage, the extent of which was then measured using propidium iodide fluorescence and immunohistochemistry images. We performed dot blotting to estimate neurotrophic/growth factor levels in the G- and S-media. Organotypic hippocampal slices cultured using S-medium after hypoxic injury were significantly less damaged than those cultured using G-medium. GLUT1, NGF, GDNF, VEGF, GCSF, and IGF2 levels were higher in S-medium than in G-medium, whereas FGF1, HIF, and MCP3 levels were not significantly different between media. In conclusion, we found that stem cell-conditioned medium had a neuroprotective effect against hypoxic injury, and that, of the various neurotrophic factors in S-medium, NGF, GDNF, and VEGF can contribute to neuroprotection. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Dosage-dependent non-linear effect of L-dopa on human motor cortex plasticity.

    PubMed

    Monte-Silva, Katia; Liebetanz, David; Grundey, Jessica; Paulus, Walter; Nitsche, Michael A

    2010-09-15

    The neuromodulator dopamine affects learning and memory formation and their likely physiological correlates, long-term depression and potentiation, in animals and humans. It is known from animal experiments that dopamine exerts a dosage-dependent, inverted U-shaped effect on these functions. However, this has not been explored in humans so far. In order to reveal a non-linear dose-dependent effect of dopamine on cortical plasticity in humans, we explored the impact of 25, 100 and 200 mg of L-dopa on transcranial direct current (tDCS)-induced plasticity in twelve healthy human subjects. The primary motor cortex served as a model system, and plasticity was monitored by motor evoked potential amplitudes elicited by transcranial magnetic stimulation. As compared to placebo medication, low and high dosages of L-dopa abolished facilitatory as well as inhibitory plasticity, whereas the medium dosage prolonged inhibitory plasticity, and turned facilitatory plasticity into inhibition. Thus the results show clear non-linear, dosage-dependent effects of dopamine on both facilitatory and inhibitory plasticity, and support the assumption of the importance of a specific dosage of dopamine optimally suited to improve plasticity. This might be important for the therapeutic application of dopaminergic agents, especially for rehabilitative purposes, and explain some opposing results in former studies.

  20. Friend or foe? An exploratory study of Australian parents' use of asynchronous discussion boards in childhood obesity.

    PubMed

    Appleton, Jessica; Fowler, Cathrine; Brown, Nicola

    2014-01-01

    The use of Internet and social media is increasing in every area of life. Parents are increasingly using online mediums to seek information about their children's health. Therefore, this is becoming an increasingly important topic area for health professionals to acknowledge. Developing an understanding about the dissemination of child health information through these online mediums will assist health professional to continue to engage and support parents to seek and share accurate and safe child health information. To explore parents' use of asynchronous online discussion boards for child health information seeking, advice and social support. A qualitative descriptive approach using an a priori template analysis was used to explore 34 discussions threads sampled from two Australian based online parenting discussion forums. To contain the scope of this study the threads chosen focused on childhood obesity in the Australian context. Four major themes related to parents' use of asynchronous online discussion boards were found. These were seeking advice, sharing advice, social support and making judgement. This final theme of making judgements included parents' perceptions of health professionals' advice. Asynchronous online discussion boards are online mediums being utilised for seeking and sharing child health related information and support between parents. The notion

  1. Needle Acupuncture for Substance Use Disorders: A Systematic Review

    DTIC Science & Technology

    2015-01-01

    RCTs). We did identify statistically significant, clinically medium effects in favor of acupuncture (as an adjunctive or monotherapy) versus any...statistically significant, clinically medium effects in favor of acupuncture (as an adjunctive or monotherapy) versus any comparator at...at postintervention. We did identify statistically significant, clinically medium effects in favor of acupuncture (as an adjunctive or monotherapy

  2. Modification of Einstein A Coefficient in Dissipative Gas Medium

    NASA Technical Reports Server (NTRS)

    Cao, Chang-Qi; Cao, Hui; Qin, Ke-Cheng

    1996-01-01

    Spontaneous radiation in dissipative gas medium such as plasmas is investigated by Langevin equations and the modified Weisskopf-Wigner approximation. Since the refractive index of gas medium is expected to be nearly unity, we shall first neglect the medium polarization effect. We show that absorption in plasmas may in certain case modify the Einstein A coefficient significantly and cause a pit in the A coefficient-density curves for relatively low temperature plasmas and also a pit in the A coefficient-temperature curves. In the next, the effect of medium polarization is taken into account in addition. To our surprise, its effect in certain case is quite significant. The dispersive curves show different behaviors in different region of parameters.

  3. Association of time-to-surgery with outcomes in clinical stage I-II pancreatic adenocarcinoma treated with upfront surgery.

    PubMed

    Swords, Douglas S; Zhang, Chong; Presson, Angela P; Firpo, Matthew A; Mulvihill, Sean J; Scaife, Courtney L

    2018-04-01

    Time-to-surgery from cancer diagnosis has increased in the United States. We aimed to determine the association between time-to-surgery and oncologic outcomes in patients with resectable pancreatic ductal adenocarcinoma undergoing upfront surgery. The 2004-2012 National Cancer Database was reviewed for patients undergoing curative-intent surgery without neoadjuvant therapy for clinical stage I-II pancreatic ductal adenocarcinoma. A multivariable Cox model with restricted cubic splines was used to define time-to-surgery as short (1-14 days), medium (15-42), and long (43-120). Overall survival was examined using Cox shared frailty models. Secondary outcomes were examined using mixed-effects logistic regression models. Of 16,763 patients, time-to-surgery was short in 34.4%, medium in 51.6%, and long in 14.0%. More short time-to-surgery patients were young, privately insured, healthy, and treated at low-volume hospitals. Adjusted hazards of mortality were lower for medium (hazard ratio 0.94, 95% confidence interval, .90, 0.97) and long time-to-surgery (hazard ratio 0.91, 95% confidence interval, 0.86, 0.96) than short. There were no differences in adjusted odds of node positivity, clinical to pathologic upstaging, being unresectable or stage IV at exploration, and positive margins. Medium time-to-surgery patients had higher adjusted odds (odds ratio 1.11, 95% confidence interval, 1.03, 1.20) of receiving an adequate lymphadenectomy than short. Ninety-day mortality was lower in medium (odds ratio 0.75, 95% confidence interval, 0.65, 0.85) and long time-to-surgery (odds ratio 0.72, 95% confidence interval, 0.60, 0.88) than short. In this observational analysis, short time-to-surgery was associated with slightly shorter OS and higher perioperative mortality. These results may suggest that delays for medical optimization and referral to high volume surgeons are safe. Published by Elsevier Inc.

  4. Pathways among Caregiver Education, Household Resources, and Infant Growth in 39 Low- and Middle-Income Countries.

    PubMed

    Bornstein, Marc H; Putnick, Diane L; Bradley, Robert H; Lansford, Jennifer E; Deater-Deckard, Kirby

    2015-01-01

    Caregiver education is known to relate to the growth of children, but possible mediation mechanisms of this association are poorly characterized and generally lack empirical support. We test whether instructional capital (caregiver education) leads to improved infant growth through availability of physical capital (household resources) across a wide swath of low- and middle-income countries (LMIC). Using the Multiple Indicator Cluster Survey (MICS3), we explore relations among caregiver education, household resources, and infant ( M age = .99 years) growth in 117,881 families living in 39 LMIC. Overall, household resources mediated 76% of the small association between caregiver education and infant growth. When disaggregated by countries characterized by low, medium, and high levels of human development (as indexed by average life expectancy, education, and gross domestic product), household resources mediated 48% to 78% of the association between caregiver education and infant growth. Caregiver education had effects on infant growth through household resources in countries characterized by low, medium, and high levels of human development; for girls and boys; and controlling for indexes of infant feeding and health.

  5. Suppression of Electron Thermal Conduction in the Intracluster Medium

    NASA Astrophysics Data System (ADS)

    Roberg-Clark, Gareth; Drake, James; Swisdak, M.; Reynolds, Christopher S.

    2017-08-01

    The Intracluster Medium (ICM) contains high-temperature dilute plasma in which the quantity beta, defined as the ratio of the thermal pressure of the gas to the local magnetic field pressure, is much larger than unity. In addition, the collisional mean free path of particles in the ICM is typically large compared to the magnetic gyro-radius of individual particles. These conditions allow for the growth of robust microinstabilities that can significantly alter the transport of particles and heat along the local magnetic field line. Here we explore such an instability using driven two-dimensional Particle-In-Cell simulations of a magnetized plasma with a temperature gradient imposed at the boundaries. The system is highly unstable and develops large-amplitude magnetic fluctuations that effectively scatter the orbits of electrons crossing the simulation domain, resulting in a collisionless suppression of thermal conduction across the temperature gradient and magnetic field. The results suggest that the spontaneous development of small-scale plasma turbulence in the ICM may play a pivotal role in determining the thermal conductivity of ICM-like plasmas.

  6. Survey of staff attitudes to the smoking ban in a medium secure unit.

    PubMed

    Garg, Shruti; Shenoy, Suraj; Badee, May; Varghese, Joe; Quinn, Patrick; Kent, John

    2009-10-01

    The aim of this survey was to explore staff attitudes to the indoor smoking ban in a medium secure unit and to ascertain if they had experienced any difficulties in imposing the ban in the four months after its introduction. All staff members available on duty who agreed to participate in the survey were interviewed using a semi-structured questionnaire. The response rate was 65%. Sixty-four percent of the staff supported the smoking ban. Forty-three percent reported experiencing patient management problems with the majority complaining of increased patient aggression, increased use of staff time in supervising patients smoking. Additionally, supervising staff were still being exposed to passive smoking. Sixty-five percent reported positive effects due to the ban with the majority reporting that patients were sleeping at night due to the smoking area being closed at night. A significant proportion of the staff is still opposed to the smoking ban. Changing staff attitudes through educational programmes will be important in ensuring success of a possible future total ban in psychiatric units. 2009 Elsevier Ltd and Faculty of Forensic and Legal Medicine.

  7. CuO Nanoparticles Inhibited Root Growth from Brassica nigra Seedlings but Induced Root from Stem and Leaf Explants.

    PubMed

    Zafar, Hira; Ali, Attarad; Zia, Muhammad

    2017-01-01

    Interests associated with nanoparticles (NPs) are budding due to their toxicity to living species. The lethal effect of NPs depends on their nature, size, shape, and concentration. Present investigation reports that CuO NPs badly affected Brassica nigra seed germination and seedling growth parameters. However, variation in antioxidative activities and nonenzymatic oxidants is observed in plantlets. Culturing the leaf and stem explants on MS medium in presence of low concentration of CuO NPs (1-20 mg l -1 ) produces white thin roots with thick root hairs. These roots also show an increase in DPPH radical scavenging activity (up to 80 % at 10 mg l -1 ), total antioxidant, and reducing power potential (maximum in presence of 10 mg l -1 CuO NPs in the media). Nonenzymatic antioxidative molecules, phenolics and flavonoids, are observed elevated but NPs concentration dependent. We can conclude that CuO NPs can induce rooting from plant explants cultured on appropriate medium. These roots can be explored for the production of active chemical constituents.

  8. A dance movement therapy group for depressed adult patients in a psychiatric outpatient clinic: effects of the treatment

    PubMed Central

    Pylvänäinen, Päivi M.; Muotka, Joona S.; Lappalainen, Raimo

    2015-01-01

    We were interested in investigating the effects of dance movement therapy (DMT) in a psychiatric outpatient clinic with patients diagnosed with depression. DMT aims to engage the patients in physical and verbal exploration of their experiences generated in movement based interaction. The assumption was that DMT, which includes both physical engagement as well as emotional and social exploration, would alleviate the mood and psychiatric symptoms. All adult patients (n = 33) included in the study received treatment as usual (TAU). Twenty-one patients participated in a 12-session DMT group intervention, and the remaining 12 patients chose to take TAU only. The majority of the patients suffered from moderate or severe depression, recurrent and/or chronic type. The effects of the interventions were investigated after the intervention, and at 3-month follow-up. Compared to the TAU, adding DMT seemed to improve the effect of the treatment. The effect of the DMT was observable whether the patient was taking antidepressant medication or not. At follow-up, between group effect sizes (ES) were medium in favor for the DMT group (d = 0.60–0.79). In the DMT group, the within ES at the 3 months follow-up varied from 0.62 to 0.82 as compared to TAU 0.15–0.37. The results indicated that DMT is beneficial in the treatment of depressed patients. PMID:26217292

  9. Medium range order in aluminum-based metallic glasses

    NASA Astrophysics Data System (ADS)

    Yi, Feng

    2011-12-01

    Medium range order (MRO) is the structure order existing between the short range order and long range order in amorphous materials. Fluctuation electron microscopy (FEM) is an effective method to quantify MRO. The FEM signal depends on several effects. In this thesis, I will show how the probe coherence, sample thickness and energy filter affect the FEM signal. We have found that microalloying in Al-based glass has dramatic effect on the primary crystallization temperature and nanocrystal density after annealing treatment. FEM alone cannot uncover the details of MRO in these alloys. Therefore, I resort to modeling to solve the relationship between the variance signal and MRO structure. I improved Stratton and Voyles's analytical model. I also did computer simulation. I explored the effects of thermal disorder and hydrostatic strain on the variance. The extracted size d and volume fraction phi in Al88Y7Fe5, Al88Y6Fe 5Cu1 and Al87Y7Fe5Cu 1 as-spun samples reveals the relationship between MRO in as-quenched sample and thermal behaviors in these alloys. I also did FEM experiments in relaxed Al88Y7Fe 5 samples at various annealing times. MRO structure in these samples does not change. FEM was also done on Al87Y7Fe5Cu 1 to check MRO variation during transient nucleation period. The extracted (d, phi) based on combination of experimental data and simulation shows how MRO changes during this period.

  10. [Effect of Tongxie Yaofang on endogenous metabolites in serum of IBS model rats].

    PubMed

    Li, Kai; Kuang, Hai-Xue; Yin, Yue; Zhang, Jie-Yu; Wang, Zhi; Zhang, Qiu-Yue; Wang, Jian-Wei

    2017-03-01

    To evaluate the effect of Tongxie Yaofang on cardiac endogenous metabolism in irritable bowel syndrome(IBS) rats by using metabolomics method, find its potential biomarkers, analyze the metabolic pathways, and explore the pharmacological effects, mechanisms of action and syndrome essence of syndrome model. Forty Wistar rats were used to establish IBS models, and then randomly divided into four groups: model control group and Tongxie Yaofang treatment groups (high, medium, low dose). Another 10 rats were used as normal group. The rats in Tongxie Yaofang-treated(low, medium and high dose) groups were orally administrated with Tongxie Yaofang extracts once a day for 2 weeks, respondingly with the doses of 0.203,0.406,0.812 g•mL⁻¹. The rats in normal group and model control group were given with equal volume of saline once a day for 2 weeks. On the 0 and 15th days, serum was collected and each sample extract was analyzed by UPLC-Q-TOF-MS. Eight potential biomarkers were identified and 8 major metabolic pathways were found to be related with IBS diseases neurotransmitter metabolism, inflammatory immunity, brain function and energy metabolism, etc. Tongxie Yaofang had certain pharmacological effects on IBS, and its mechanism may be related to serotonergic synapse, tryptophan metabolism, cysteine and methionine metabolism, glycerophospholipid metabolism, nicotinate and nicotinamide metabolism and so on, which might be the biological basis of IBS liver-spleen deficiency syndrome. Copyright© by the Chinese Pharmaceutical Association.

  11. Effects of alternative energy sources on bacterial cellulose characteristics produced by Komagataeibacter medellinensis.

    PubMed

    Molina-Ramírez, Carlos; Enciso, Carla; Torres-Taborda, Mabel; Zuluaga, Robin; Gañán, Piedad; Rojas, Orlando J; Castro, Cristina

    2018-05-27

    Bacterial cellulose (BC) was produced by Komagataeibacter medellinensis using Hestrin and Schramm modified medium in the presence of alternative energy sources (AES), such as ethanol and acetic acid, to explore the effect of AES on the characteristics and properties of the resulting BC. In this study, the physicochemical and structural characteristics of the obtained BC were determined using Fourier-transform infrared spectroscopy, X-ray diffraction spectrometry, thermogravimetric analysis, and mechanical testing analysis. Ethanol and acetic acid (at 0.1 wt%) were proven to improve the BC yield by K. medellinensis by 279% and 222%, respectively. However, the crystallinity index (%), the degree of polymerization, and maximum rate of degradation temperatures decreased by 9.2%, 36%, and 4.96%, respectively, by the addition of ethanol and by 7.2%, 27%, and 4.21%, respectively, by the addition of acetic acid. The significance of this work, lies on the fact that there is not any report about how BC properties change when substances like ethanol or acetic acid are added to culture medium, and which is the mechanism that provokes those changes, that in our case we could demonstrate the relationship of a higher BC production rate (provoked by ethanol and acetic acid adding) and changes in BC properties. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Pituitary tumour causing gigantism. Morphology and in vitro hormone secretion.

    PubMed

    Anniko, M; Ritzén, E M

    1986-01-01

    True gigantism with overproduction of growth hormone (GH) and prolactin (PRL) was diagnosed in a 13-year-old boy. The clinical history indicated that the tumour had caused an oversecretion of GH since the age of 4-5 years. At diagnosis, the sella turcica was markedly enlarged. No infiltrative growth was noted at surgery. Endocrine investigations showed elevated GH and PRL secretion. Light and electron microscopy of tumour tissue revealed densely packed pleomorphic cells of both GH and PRL type. In addition, oncocyte-like cells were observed. Organ culture of pieces of tumour tissue demonstrated continued secretion of GH and PRL into the medium for more than 5 days in vitro. Addition of bromocriptine to the medium caused a rapid decline in PRL secretion while GH secretion remained the same. X-ray irradiation in vitro also caused a decrease in PRL secretion. These effects of bromocriptine and X-ray on hormone secretion in vitro mirrored the corresponding effect of treatment, when the patient showed signs of tumour recurrence after pituitary surgery. It is concluded that also in childhood, the in vitro response of tumour tissue to various treatments may be explored as a possible way to predict the efficacy of pharmacological or irradiation treatment of pituitary tumours.

  13. Water-Soluble Nonconjugated Polymer Nanoparticles with Strong Fluorescence Emission for Selective and Sensitive Detection of Nitro-Explosive Picric Acid in Aqueous Medium.

    PubMed

    Liu, Shi Gang; Luo, Dan; Li, Na; Zhang, Wei; Lei, Jing Lei; Li, Nian Bing; Luo, Hong Qun

    2016-08-24

    Water-soluble nonconjugated polymer nanoparticles (PNPs) with strong fluorescence emission were prepared from hyperbranched poly(ethylenimine) (PEI) and d-glucose via Schiff base reaction and self-assembly in aqueous phase. Preparation of the PEI-d-glucose (PEI-G) PNPs was facile (one-pot reaction) and environmentally friendly under mild conditions. Also, PEI-G PNPs showed a high fluorescence quantum yield in aqueous solution, and the fluorescence properties (such as concentration- and solvent-dependent fluorescence) and origin of intrinsic fluorescence were investigated and discussed. PEI-G PNPs were then used to develop a fluorescent probe for fast, selective, and sensitive detection of nitro-explosive picric acid (PA) in aqueous medium, because the fluorescence can be easily quenched by PA whereas other nitro-explosives and structurally similar compounds only caused negligible quenching. A wide linear range (0.05-70 μM) and a low detection limit (26 nM) were obtained. The fluorescence quenching mechanism was carefully explored, and it was due to a combined effect of electron transfer, resonance energy transfer, and inner filter effect between PA and PEI-G PNPs, which resulted in good selectivity and sensitivity for PA. Finally, the developed sensor was successfully applied to detection of PA in environmental water samples.

  14. Effects of coformers on phase transformation and release profiles of carbamazepine cocrystals in hydroxypropyl methylcellulose based matrix tablets.

    PubMed

    Qiu, Shi; Li, Mingzhong

    2015-02-01

    The aim of this study was to investigate the effects of coformers on phase transformation and release profiles of carbamazepine (CBZ) cocrystals in hydroxypropyl methylcellulose (HPMC) based matrix tablets. It has been found that selection of different coformers of saccharin (SAC) and cinnamic acid (CIN) can affect the stability of CBZ cocrystals in solution, resulting in significant differences in the apparent solubility of CBZ. The dissolution advantage of CBZ-SAC cocrystals can only be shown for a short period during dissolution because of the fast conversion to its dihydrate form (DH). HPMC can partially inhibit the crystallisation of CBZ DH during dissolution of CBZ-SAC cocrystal. However, the increased viscosity of HPMC dissolution medium reduced the dissolution rate of CBZ-SAC cocrystals. Therefore the CBZ-SAC cocrystal formulation did not show any significant advantage in CBZ release rate. In contrast the improved CBZ dissolution rate of CBZ-CIN cocrystal can be realised in both solution and formulation due to its high stability. In conclusion, exploring and understanding the mechanisms of the phase transformation of pharmaceutical cocrystals in aqueous medium for selection of lead cocrystals is the key for success of product development. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Role for RIP1 in mediating necroptosis in experimental intracerebral hemorrhage model both in vivo and in vitro.

    PubMed

    Shen, Haitao; Liu, Chenglin; Zhang, Dongping; Yao, Xiyang; Zhang, Kai; Li, Haiying; Chen, Gang

    2017-03-02

    Cell death is a hallmark of second brain injury after intracerebral hemorrhage (ICH); however, the mechanism still has not been fully illustrated. In this study, we explored whether necroptosis, a type of regulated necrosis, has an essential role in brain injury after ICH. We found that inhibiting receptor-interacting protein 1 (RIP1) - a core element of the necroptotic pathway - by a specific chemical inhibitor or genetic knockdown attenuated brain injury in a rat model of ICH. Furthermore, necroptosis of cultured neurons could be induced by conditioned medium from microglia stimulated with oxygen hemoglobin, and this effect could be inhibited by TNF-α inhibitor, indicating that TNF-α secreted from activated microglia is an important factor in inducing necroptosis of neurons. Undoubtedly, overexpression of RIP1 increased conditioned medium-induced necroptosis in vitro, but this effect was partially diminished in mutation of serine kinase phosphorylation site of RIP1, showing that phosphorylation of RIP1 is the essential molecular mechanism of necroptosis, which was activated in the in vitro model of ICH. Collectively, our investigation identified that necroptosis is an important mechanism of cell death in brain injury after ICH, and inhibition of necroptosis may be a potential therapeutic intervention of ICH.

  16. Role for RIP1 in mediating necroptosis in experimental intracerebral hemorrhage model both in vivo and in vitro

    PubMed Central

    Shen, Haitao; Liu, Chenglin; Zhang, Dongping; Yao, Xiyang; Zhang, Kai; Li, Haiying; Chen, Gang

    2017-01-01

    Cell death is a hallmark of second brain injury after intracerebral hemorrhage (ICH); however, the mechanism still has not been fully illustrated. In this study, we explored whether necroptosis, a type of regulated necrosis, has an essential role in brain injury after ICH. We found that inhibiting receptor-interacting protein 1 (RIP1) – a core element of the necroptotic pathway – by a specific chemical inhibitor or genetic knockdown attenuated brain injury in a rat model of ICH. Furthermore, necroptosis of cultured neurons could be induced by conditioned medium from microglia stimulated with oxygen hemoglobin, and this effect could be inhibited by TNF-α inhibitor, indicating that TNF-α secreted from activated microglia is an important factor in inducing necroptosis of neurons. Undoubtedly, overexpression of RIP1 increased conditioned medium-induced necroptosis in vitro, but this effect was partially diminished in mutation of serine kinase phosphorylation site of RIP1, showing that phosphorylation of RIP1 is the essential molecular mechanism of necroptosis, which was activated in the in vitro model of ICH. Collectively, our investigation identified that necroptosis is an important mechanism of cell death in brain injury after ICH, and inhibition of necroptosis may be a potential therapeutic intervention of ICH. PMID:28252651

  17. Concerns With Entertainment-Education: Zombie Pandemic Preparedness and the Unanticipated Promotion of a Weapons Culture.

    PubMed

    Houghton, Frank; Toms, Jeremy; Meratnia, Ghazal; Loney, Krista; Hopkins, Edward; Del Monte, Katie

    2017-08-01

    Entertainment-education has proved to be an engaging medium through which to explore health and social issues in populations. Given the popularity of the zombie theme in popular culture it is no surprise therefore that the Centers for Disease Control and Prevention adopted this theme in an effort to engage youth and young adults in emergency preparedness. However, an earlier observational study involving elementary school children based on this premise raised concerns that it may have unexpectedly promoted a focus on firearms. A randomized control study involving 89 children (average age 10.4 years) was therefore conducted to explore this possibility in more depth. One group was exposed to a natural disaster scenario, while the other group was exposed to the zombie pandemic theme. When subsequently asked to prepare emergency kit lists, participants in the zombie themed scenario were 15.84 times as likely to include firearms in their lists compared with participants who were exposed to the natural disaster scenario. Although the sample size in this study was small, it is suggested that future interventions using entertainment-education need to explore all aspects of the messages implicit in their chosen medium, rather than just focusing on one element.

  18. The Interstellar Heliopause Probe/Heliospheric Explorer: IHP/HEX

    NASA Astrophysics Data System (ADS)

    Wimmer-Schweingruber, Robert F.; McNutt, Ralph L.

    2010-03-01

    The Sun, driving a supersonic solar wind, cuts out of the local interstellar medium a giant plasma bubble, the heliosphere. Dedicated deep-space missions have greatly enhanced our understanding of our immediate neighborhood. Ulysses is the only spacecraft exploring the third, out-of-ecliptic dimension, while SOHO has allowed us to better understand the influence of the Sun and to image the glow of interstellar matter in the heliosphere. Both Voyager spacecraft have recently encountered the innermost boundary of this plasma bubble, the termination shock, and are returning exciting yet puzzling data of this remote region. The next logical step is to leave the heliosphere and to thereby map out in unprecedented detail the structure of the outer heliosphere and its boundaries, the termination shock, the heliosheath, the heliopause, and, after leaving the heliosphere, to discover the true nature of the hydrogen wall, the bow shock, and the local interstellar medium beyond. This will greatly advance our understanding of the heliosphere that is the best-known example for astrospheres as found around other stars. Thus, IHP/HEX will allow us to discover, explore, and understand fundamental astrophysical processes in the largest accessible plasma laboratory, the heliosphere.

  19. First Results from the Interstellar Boundary Explorer (IBEX) Mission

    NASA Astrophysics Data System (ADS)

    McComas, David J.

    2010-03-01

    The Interstellar Boundary Explorer (IBEX) is a Small Explorer mission designed to study the global interaction between the heliosphere and the local interstellar medium. IBEX does this by measuring energetic neutral atoms (ENAs) created by both solar wind ions and pickup ions in the solar wind when they charge exchange with cold interstellar neutrals drifting in from the interstellar medium. Because the ENAs are not magnetically confined, some of them propagate back into the inner heliosphere, where IBEX can detect them. IBEX was launched October 19th 2008, using a new launch technique that was also developed as a part of the IBEX project. The first scientific observations from IBEX were of ENAs coming from the Moon-these represented the first ever lunar ENA observations from any spacecraft and provided important information about the universal physical processes of backscatter and neutralization from complex planetary surfaces like the lunar regolith. Since then, IBEX has been collecting its first all-sky maps of heliospheric ENAs and initial direct, in situ observations of interstellar H, He, and O. At the time of this writing, these observations have been submitted and are under review for a special IBEX section of Science magazine nominally scheduled to be published in October 2009.

  20. NASA's first in-space optical gyroscope: A technology experiment on the X ray Timing Explorer spacecraft

    NASA Technical Reports Server (NTRS)

    Unger, Glenn; Kaufman, David M.; Krainak, Michael; Sanders, Glenn; Taylor, Bill; Schulze, Norman R.

    1993-01-01

    A technology experiment on the X-ray Timing Explorer spacecraft to determine the feasibility of Interferometric Fiber Optic Gyroscopes for space flight navigation is described. The experiment consists of placing a medium grade fiber optic gyroscope in parallel with the spacecraft's inertial reference unit. The performance of the fiber optic gyroscope will be monitored and compared to the primary mechanical gyroscope's performance throughout the two-year mission life.

  1. Instability of supersonic cold streams feeding galaxies - I. Linear Kelvin-Helmholtz instability with body modes

    NASA Astrophysics Data System (ADS)

    Mandelker, Nir; Padnos, Dan; Dekel, Avishai; Birnboim, Yuval; Burkert, Andreas; Krumholz, Mark R.; Steinberg, Elad

    2016-12-01

    Massive galaxies at high redshift are predicted to be fed from the cosmic web by narrow, dense streams of cold gas that penetrate through the hot medium encompassed by a stable shock near the virial radius of the dark-matter halo. Our long-term goal is to explore the heating and dissipation rate of the streams and their fragmentation and possible breakup, in order to understand how galaxies are fed, and how this affects their star formation rate and morphology. We present here the first step, where we analyse the linear Kelvin-Helmholtz instability (KHI) of a cold, dense slab or cylinder in 3D flowing supersonically through a hot, dilute medium. The current analysis is limited to the adiabatic case with no gravity. By analytically solving the linear dispersion relation, we find a transition from a dominance of the familiar rapidly growing surface modes in the subsonic regime to more slowly growing body modes in the supersonic regime. The system is parametrized by three parameters: the density contrast between stream and medium, the Mach number of stream velocity with respect to the medium and the stream width with respect to the halo virial radius. A realistic choice for these parameters places the streams near the mode transition, with the KHI exponential-growth time in the range 0.01-10 virial crossing times for a perturbation wavelength comparable to the stream width. We confirm our analytic predictions with idealized hydrodynamical simulations. Our linear estimates thus indicate that KHI may be effective in the evolution of streams before they reach the galaxy. More definite conclusions await the extension of the analysis to the non-linear regime and the inclusion of cooling, thermal conduction, the halo potential well, self-gravity and magnetic fields.

  2. Effect of environmental and cultural conditions on medium pH and explant growth performance of Douglas-fir ( Pseudotsuga menziesii) shoot cultures

    PubMed Central

    Chen, Chien-Chih; Bates, Rick; Carlson, John

    2015-01-01

    The medium pH level of plant tissue cultures has been shown to be essential to many aspects of explant development and growth. Sensitivity or tolerance of medium pH change in vitro varies according to specific requirements of individual species. The objectives of this study are to 1) determine medium pH change over time in storage conditions and with presence of explants, 2) evaluate the effects of medium pH change on explant growth performance and 3) assess the effects of adding a pH stabilizer, 2-(N-morpholino)ethanesulfonic acid (MES) that is commonly used in Douglas-fir micropropagation medium. Vegetative buds were collected in the spring before breaking dormancy from juvenile and mature donor trees for conducting these evaluations. Medium, with or without MES, was pre-adjusted to five pH levels before adding MES, agar and autoclaving. Medium pH changes and explant growth parameters were measured at eight different incubation times. Overall, MES provided a more stable medium pH, relative to starting pH values, under both light and dark storage conditions as well as with presence of explants. A general trend of decreasing medium pH over time was found comparing explants from juvenile and mature donor genotypes. Explant height and weight growth increased over time, but differ among explants from juvenile and mature donor genotypes. Our findings suggest that a 21-day subculture practice may best sustain medium freshness, medium pH level and desirable explant growth. PMID:26535110

  3. Contact Angle Measurements: an Alternative Approach Towards Understanding the Mechanism of Increased Drug Dissolution from Ethylcellulose Tablets Containing Surfactant and Exploring the Relationship Between Their Contact Angles and Dissolution Behaviors.

    PubMed

    Liu, Tiaotiao; Hao, Jingqiang; Yang, Baixue; Hu, Beibei; Cui, Zhixiang; Li, Sanming

    2018-05-01

    The addition of surfactant in tablet was a well-defined approach to improve drug dissolution rate. While the selected surfactant played a vital role in improving the wettability of tablet by medium, it was equally important to improve the dissolution rate by permeation effect due to production of pores or the reduced inter-particle adhesion. Furthermore, understanding the mechanism of dissolution rate increased was significant. In this work, contact angle measurement was taken up as an alternative approach for understanding the dissolution rate enhancement for tablet containing surfactant. Ethylcellulose, as a substrate, was used to prepare tablet. Four surfactants, sodium dodecyl sulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), dodecyltrimethylammonium bromide (DTAB), and sodium lauryl sulfonate (SLS), were used. Berberine hydrochloride, metformin hydrochloride, and rutin were selected as model drugs. The contact angle of tablet in the absence and presence of surfactant was measured to explore the mechanism. The dissolution test was investigated to verify the mechanism and to establish a correlation with the contact angle. The result showed that the mechanism was the penetration effect rather than the wetting effect. The dissolution increased with a reduction in the contact angle. DTAB was found to obtain the highest level of dissolution enhancement and the lowest contact angle, while SDS, SDBS, and SLS were found to be the less effective in both dissolution enhancement and contact angle decrease. Therefore, contact angle was a good indicator for dissolution behavior besides exploring the mechanism of increased dissolution, which shows great potential in formula screening.

  4. Characterization of a novel epigenetic effect of ionizing radiation: the death-inducing effect

    NASA Technical Reports Server (NTRS)

    Nagar, Shruti; Smith, Leslie E.; Morgan, William F.

    2003-01-01

    The detrimental effects associated with exposure to ionizing radiation have long been thought to result from the direct targeting of the nucleus leading to DNA damage; however, the emergence of concepts such as radiation-induced genomic instability and bystander effects have challenged this dogma. After cellular exposure to ionizing radiation, we have isolated a number of clones of Chinese hamster-human hybrid GM10115 cells that demonstrate genomic instability as measured by chromosomal destabilization. These clones show dynamic and persistent generation of chromosomal rearrangements multiple generations after the original insult. We hypothesize that these unstable clones maintain this delayed instability phenotype by secreting factors into the culture medium. To test this hypothesis we transferred filtered medium from unstable cells to unirradiated GM10115 cells. No GM10115 cells were able to survive this medium. This phenomenon by which GM10115 cells die when cultured in medium from chromosomally unstable GM10115 clones is the death-inducing effect. Medium transfer experiments indicate that a factor or factors is/are secreted by unstable cells within 8 h of growth in fresh medium and result in cell killing within 24 h. These factors are stable at ambient temperature but do not survive heating or freezing, and are biologically active when diluted with fresh medium. We present the initial description and characterization of the death-inducing effect. This novel epigenetic effect of radiation has implications for radiation risk assessment and for health risks associated with radiation exposure.

  5. Poly(γ-Glutamic Acid) as an Exogenous Promoter of Chondrogenic Differentiation of Human Mesenchymal Stem/Stromal Cells.

    PubMed

    Antunes, Joana C; Tsaryk, Roman; Gonçalves, Raquel M; Pereira, Catarina Leite; Landes, Constantin; Brochhausen, Christoph; Ghanaati, Shahram; Barbosa, Mário A; Kirkpatrick, C James

    2015-06-01

    Cartilage damage and/or aging effects can cause constant pain, which limits the patient's quality of life. Although different strategies have been proposed to enhance the limited regenerative capacity of cartilage tissue, the full production of native and functional cartilaginous extracellular matrix (ECM) has not yet been achieved. Poly(γ-glutamic acid) (γ-PGA), a naturally occurring polyamino acid, biodegradable into glutamate residues, has been explored for tissue regeneration. In this work, γ-PGA's ability to support the production of cartilaginous ECM by human bone marrow mesenchymal stem/stromal cells (MSCs) and nasal chondrocytes (NCs) was investigated. MSC and NC pellets were cultured in basal medium (BM), chondrogenic medium (CM), and CM-γ-PGA-supplemented medium (CM+γ-PGA) over a period of 21 days. Pellet size/shape was monitored with time. At 14 and 21 days of culture, the presence of sulfated glycosaminoglycans (sGAGs), type II collagen (Col II), Sox-9, aggrecan, type XI collagen (Col XI), type X collagen (Col X), calcium deposits, and type I collagen (Col I) was analyzed. After excluding γ-PGA's cytotoxicity, earlier cell condensation, higher sGAG content, Col II, Sox-9 (day 14), aggrecan, and Col X (day 14) production was observed in γ-PGA-supplemented MSC cultures, with no signs of mineralization or Col I. These effects were not evident with NCs. However, Sox-9 (at day 14) and Col X (at days 14 and 21) were increased, decreased, or absent, respectively. Overall, γ-PGA improved chondrogenic differentiation of MSCs, increasing ECM production earlier in culture. It is proposed that γ-PGA incorporation in novel biomaterials has a beneficial impact on future approaches for cartilage regeneration.

  6. Effect of clomiphene on Ca(2+) movement in human prostate cancer cells.

    PubMed

    Jiann, Bang-Ping; Lu, Yih-Chau; Chang, Hong-Tai; Huang, Jong-Khing; Jan, Chung-Ren

    2002-05-17

    The effect of clomiphene, an ovulation-inducing agent, on cytosolic free Ca(2+) levels ([Ca(2+)](i)) in populations of PC3 human prostate cancer cells was explored by using fura-2 as a Ca(2+) indicator. Clomiphene at concentrations between 10-50 microM increased [Ca(2+)](i) in a concentration-dependent manner. The [Ca(2+)](i) signal was biphasic with an initial rise and a slow decay. Ca(2+) removal inhibited the Ca(2+) signal by 41%. Adding 3 mM Ca(2+) increased [Ca(2+)](i) in cells pretreated with clomiphene in Ca(2+)-free medium, confirming that clomiphene induced Ca(2+) entry. In Ca(2+)-free medium, pretreatment with 50 microM brefeldin A (to permeabilize the Golgi complex), 1 microM thapsigargin (to inhibit the endoplasmic reticulum Ca(2+) pump), and 2 microM carbonylcyanide m-chlorophenylhydrazone (to uncouple mitochondria) inhibited 25% of 50 microM clomiphene-induced store Ca(2+) release. Conversely, pretreatment with 50 microM clomiphene in Ca(2+)-free medium abolished the [Ca(2+)](i) increase induced by brefeldin A, thapsigargin or carbonylcyanide m-chlorophenylhydrazone. The 50 microM clomiphene-induced Ca(2+)release was unaltered by inhibiting phospholipase C with 2 microM 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122). Trypan blue exclusion assay suggested that incubation with clomiphene (50 microM) for 2-15 min induced time-dependent decrease in cell viability by 10-50%. Collectively, the results suggest that clomiphene induced [Ca(2+)](i) increases in PC3 cells by releasing store Ca(2+) from multiple stores in an phospholipase C-independent manner, and by activating Ca(2+) influx; and clomiphene was of mild cytotoxicity.

  7. Valproic acid attenuates skeletal muscle wasting by inhibiting C/EBPβ-regulated atrogin1 expression in cancer cachexia.

    PubMed

    Sun, Rulin; Zhang, Santao; Hu, Wenjun; Lu, Xing; Lou, Ning; Yang, Zhende; Chen, Shaoyong; Zhang, Xiaoping; Yang, Hongmei

    2016-07-01

    Muscle wasting is the hallmark of cancer cachexia and is associated with poor quality of life and increased mortality. Valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, has important biological effects in the treatment of muscular dystrophy. To verify whether VPA could ameliorate muscle wasting induced by cancer cachexia, we explored the role of VPA in two cancer cachectic mouse models [induced by colon-26 (C26) adenocarcinoma or Lewis lung carcinoma (LLC)] and atrophied C2C12 myotubes [induced by C26 cell conditioned medium (CCM) or LLC cell conditioned medium (LCM)]. Our data demonstrated that treatment with VPA increased the mass and cross-sectional area of skeletal muscles in tumor-bearing mice. Furthermore, treatment with VPA also increased the diameter of myotubes cultured in conditioned medium. The skeletal muscles in cachectic mice or atrophied myotubes treated with VPA exhibited reduced levels of CCAAT/enhancer binding protein beta (C/EBPβ), resulting in atrogin1 downregulation and the eventual alleviation of muscle wasting and myotube atrophy. Moreover, atrogin1 promoter activity in myotubes was stimulated by CCM via activating the C/EBPβ-responsive cis-element and subsequently inhibited by VPA. In contrast to the effect of VPA on the levels of C/EBPβ, the levels of inactivating forkhead box O3 (FoxO3a) were unaffected. In summary, VPA attenuated muscle wasting and myotube atrophy and reduced C/EBPβ binding to atrogin1 promoter locus in the myotubes. Our discoveries indicate that HDAC inhibition by VPA might be a promising new approach for the preservation of skeletal muscle in cancer cachexia. Copyright © 2016 the American Physiological Society.

  8. Poly(γ-Glutamic Acid) as an Exogenous Promoter of Chondrogenic Differentiation of Human Mesenchymal Stem/Stromal Cells

    PubMed Central

    Antunes, Joana C.; Tsaryk, Roman; Gonçalves, Raquel M.; Pereira, Catarina Leite; Landes, Constantin; Brochhausen, Christoph; Ghanaati, Shahram

    2015-01-01

    Cartilage damage and/or aging effects can cause constant pain, which limits the patient's quality of life. Although different strategies have been proposed to enhance the limited regenerative capacity of cartilage tissue, the full production of native and functional cartilaginous extracellular matrix (ECM) has not yet been achieved. Poly(γ-glutamic acid) (γ-PGA), a naturally occurring polyamino acid, biodegradable into glutamate residues, has been explored for tissue regeneration. In this work, γ-PGA's ability to support the production of cartilaginous ECM by human bone marrow mesenchymal stem/stromal cells (MSCs) and nasal chondrocytes (NCs) was investigated. MSC and NC pellets were cultured in basal medium (BM), chondrogenic medium (CM), and CM-γ-PGA-supplemented medium (CM+γ-PGA) over a period of 21 days. Pellet size/shape was monitored with time. At 14 and 21 days of culture, the presence of sulfated glycosaminoglycans (sGAGs), type II collagen (Col II), Sox-9, aggrecan, type XI collagen (Col XI), type X collagen (Col X), calcium deposits, and type I collagen (Col I) was analyzed. After excluding γ-PGA's cytotoxicity, earlier cell condensation, higher sGAG content, Col II, Sox-9 (day 14), aggrecan, and Col X (day 14) production was observed in γ-PGA-supplemented MSC cultures, with no signs of mineralization or Col I. These effects were not evident with NCs. However, Sox-9 (at day 14) and Col X (at days 14 and 21) were increased, decreased, or absent, respectively. Overall, γ-PGA improved chondrogenic differentiation of MSCs, increasing ECM production earlier in culture. It is proposed that γ-PGA incorporation in novel biomaterials has a beneficial impact on future approaches for cartilage regeneration. PMID:25760236

  9. Revisiting the effective medium approximation in all-dielectric subwavelength multilayers: Breakdown and rebuilding

    NASA Astrophysics Data System (ADS)

    Lei, Xinrui; Mao, Lei; Lu, Yonghua; Wang, Pei

    2017-07-01

    Here, we present a comprehensive analysis of the effective medium approximation (EMA) breakdown in all-dielectric deep-subwavelength multilayers made of alternating layers by means of the transfer matrix method. We demonstrated that the approximation is invalid at the vicinity of the effective medium's critical angle for total internal reflection and obtained an analytical criterion for the breakdown of the EMA, which depends on the layer thickness, the incident angle, and the permittivity difference between the alternate layers. We rebuilt the EMA by adding higher-order correction onto the traditional effective permittivity. Furthermore, we found that the EMA breakdown that arises from the boundary effect cannot be repaired in the traditional homogenization strategy with only one layer of effective medium. By adding an artificial matched layer after the conventional effective layer, the boundary effect breakdown was neatly removed.

  10. Artificial dispersion via high-order homogenization: magnetoelectric coupling and magnetism from dielectric layers

    PubMed Central

    Liu, Yan; Guenneau, Sébastien; Gralak, Boris

    2013-01-01

    We investigate a high-order homogenization (HOH) algorithm for periodic multi-layered stacks. The mathematical tool of choice is a transfer matrix method. Expressions for effective permeability, permittivity and magnetoelectric coupling are explored by frequency power expansions. On the physical side, this HOH uncovers a magnetoelectric coupling effect (odd-order approximation) and artificial magnetism (even-order approximation) in moderate contrast photonic crystals. Comparing the effective parameters' expressions of a stack with three layers against that of a stack with two layers, we note that the magnetoelectric coupling effect vanishes while the artificial magnetism can still be achieved in a centre-symmetric periodic structure. Furthermore, we numerically check the effective parameters through the dispersion law and transmission property of a stack with two dielectric layers against that of an effective bianisotropic medium: they are in good agreement throughout the low-frequency (acoustic) band until the first stop band, where the analyticity of the logarithm function of the transfer matrix () breaks down. PMID:24101891

  11. Future of Ultraviolet Astronomy Based on Six Years of IUE Research

    NASA Technical Reports Server (NTRS)

    Mead, J. M. (Editor); Chapman, R. D. (Editor); Kondo, Y. (Editor)

    1984-01-01

    Physical insights into the various astronomical objects which were studied using the International Ultraviolet Explorer (IUE) satellite. Topics covered included galaxies, cool stars, hot stars, close binaries, variable stars, the interstellar medium, the solar system, and IUE follow-on missions.

  12. Web Usage, Advertising, and Shopping: Relationship Patterns.

    ERIC Educational Resources Information Center

    Korgaonkar, Pradeep; Wolin, Lori D.

    2002-01-01

    Discusses Web sales and explores the differences between heavy, medium, and light Web users in terms of their beliefs about Web advertising, attitudes toward Web advertising, purchasing patterns, and demographics. Suggests marketers need to target Web advertising to particular Web users. (Author/LRW)

  13. Revolution in the Small Colleges.

    ERIC Educational Resources Information Center

    Heger, Herbert K.

    1982-01-01

    Small and medium-sized institutions are seen as likely to experience major organizational change during the next few years in three areas: contracting out, academic franchising, and reacting to declining instruction. Colleges need to explore interinstitutional cooperation, new educational media, structural innovation, productivity improvement, and…

  14. Proceedings of the Symposium on the Study of the Sun and Interplanetary Medium in Three Dimensions. [space mission planning and interplanetary trajectories by NASA and ESA to better observe the sun and solar system

    NASA Technical Reports Server (NTRS)

    Fisk, L. A. (Editor); Axford, W. I. (Editor)

    1976-01-01

    A series of papers are presented from a symposium attended by over 200 European and American scientists to examine the importance of exploring the interplanetary medium and the sun by out-of-the-ecliptic space missions. The likely scientific returns of these missions in the areas of solar, interplanetary, and cosmic ray physics is examined. Theoretical models of the solar wind and its interaction with interplanetary magnetic fields are given.

  15. In a different voice: promises and trials of non-English medium journals

    NASA Astrophysics Data System (ADS)

    Lee, Yew-Jin

    2015-12-01

    Various issues confronting science education publications that cater for non-English speaking audiences are explored. With reference to an English-medium journal that the author co-edits, two main conundrums are discussed: (1) How to serve local school practitioners in concrete ways while fulfilling the institutional goals of academia, and (2) the struggle to promote research from non-English speaking contexts against the hegemony of the English language. It is suggested that valuing difference can create much educational value and thereby allow one's science teaching to be interrogated, evolve, and maintain its relevancy.

  16. Correlation effects during liquid infiltration into hydrophobic nanoporous media

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

    Borman, V. D., E-mail: vdborman@mephi.ru; Belogorlov, A. A.; Byrkin, V. A.

    To explain the thermal effects observed during the infiltration of a nonwetting liquid into a disordered nanoporous medium, we have constructed a model that includes correlation effects in a disordered medium. It is based on analytical methods of the percolation theory. The infiltration of a porous medium is considered as the infiltration of pores in an infinite cluster of interconnected pores. Using the model of randomly situated spheres (RSS), we have been able to take into account the correlation effect of the spatial arrangement and connectivity of pores in the medium. The other correlation effect of the mutual arrangement ofmore » filled and empty pores on the shell of an infinite percolation cluster of filled pores determines the infiltration fluctuation probability. This probability has been calculated analytically. Allowance for these correlation effects during infiltration and defiltration makes it possible to suggest a physical mechanism of the contact angle hysteresis and to calculate the dependences of the contact angles on the degree of infiltration, porosity of the medium, and temperature. Based on the suggested model, we have managed to describe the temperature dependences of the infiltration and defiltration pressures and the thermal effects that accompany the absorption of energy by disordered porous medium-nonwetting liquid systems with various porosities in a unified way.« less

  17. Dexamethasone implant in silicone oil: in vitro behavior.

    PubMed

    Flores-Villalobos, Erick Omar; Ramírez-Estudillo, J Abel; Robles-Contreras, Atzin; Oliva-Ramírez, Jacqueline L

    2018-01-01

    To determine the effect of the silicone on the dexamethasone intravitreal implant. Basic, experimental, prospective and transversal study performed at the hospital "Nuestra Señora de la Luz" in Mexico City. One dexamethasone implant was placed in a test tube with 4 mL of each tamponade medium: 1000cS, 5000cS and heavy silicone oil; basic saline solution was used as the control medium. Photographs were taken weekly for 12 months. 200 µL samples were taken from each medium at 24 h, 1, 2 weeks and monthly for 12 months. ELISA test was performed to quantify dexamethasone release in every sample. An inflammatory stimulus was created and later exposed it to every sample in order to test their anti-inflammatory capacity by cytokine analysis using cytometric bead array. Statistically significant results were obtained with p < 0.05. Photographic follow-up showed disintegration of the implant in control medium. Implants in silicone oil suffered no changes during follow-up. Dexamethasone levels in control medium showed stability from month 2 to 12. Silicone oil mediums showed irregular dexamethasone release during the 1 year period. Dexamethasone in control medium had inhibitory effects on TNF-α starting at 24 h (p < 0.001) and remained stable. Dexamethasone in 1000cS silicone oil showed inhibitory effects from month 2 (p < 0.001) until month 6 (p < 0.001). Implants in denser silicone oils showed no inhibitory effects in any of the samples. Denser mediums altered the implant pharmacokinetics and showed no anti-inflammatory effects even when concentrations were quantified at levels similar to control medium in vitro.

  18. Effect of Acidity of a Medium on Riboflavin Photodestruction

    NASA Astrophysics Data System (ADS)

    Astanov, S. Kh.; Turdiev, M.; Sharipov, M. Z.; Kurtaliev, É. N.; Nizomov, N. N.

    2016-03-01

    Effect of acidity of a medium on the spectroscopic characteristics of riboflavin aqueous solutions is investigated by the method of fluorescent and absorption spectroscopy. Significant deformation of the electronic spectra of riboflavin aqueous solutions irradiated with unfiltered light of a PRK-2 lamp is observed. It is established that riboflavin photostability in an acid medium is about twice as much as the photostability in a neutral medium, which is caused by the formation of a protonated species.

  19. The moderating effects of skin color and ethnic identity affirmation on suicide risk among low-SES African American women.

    PubMed

    Perry, Brea L; Stevens-Watkins, Danelle; Oser, Carrie B

    2013-03-01

    This study examined the influence of concurrent racism and sexism experiences (i.e. gendered racism) on African American women's suicidal ideation and behavior in the context of disadvantaged socioeconomic status. Drawing on a stress process framework, the moderating effects of ethnic identity and skin color were explored using multiple regression analyses. Data were from 204 low-income African American women in the B-WISE (Black Women in a Study of Epidemics) project. Findings suggested that experiencing gendered racism significantly increased these women's risk for suicidal ideation or behavior, though only among women with medium or dark skin color. Also, having strong ethnic identity buffered the harmful effects of gendered racism. The moderating properties of skin color and ethnic identity affirmation likely operate through psychosocial pathways, blocking internalization of negative stereotypes and reducing the level of distress experienced in response to gendered racism.

  20. Reaching adolescent girls through social networking: a new avenue for smoking prevention messages.

    PubMed

    Struik, Laura Louise; Bottorff, Joan L; Jung, Mary; Budgen, Claire

    2012-09-01

    Because adolescent girls are being targeted on social networking sites by the tobacco industry, new online tobacco control (TC) initiatives are needed. The purpose of this interpretive descriptive study was to explore adolescent girls' perspectives on the use of social networking sites to deliver TC messages targeting young women. Focus groups were conducted with 17 girls aged 16 to 19. Seven TC messages were provided for evaluation and as context for discussion about the delivery of TC messages on social networking sites. Data were analyzed for themes, which included concerns about the effectiveness of current TC messages and the stereotypical representations of gender, factors perceived to influence the effectiveness of TC messages on social networking sites, and suggestions for enhancing the effectiveness of TC messages placed on social networking sites. Endorsement of TC messaging on social networking sites suggests that this medium is an untapped resource for smoking prevention.

  1. Giant Kerr response of ultrathin gold films from quantum size effect.

    PubMed

    Qian, Haoliang; Xiao, Yuzhe; Liu, Zhaowei

    2016-10-10

    With the size of plasmonic devices entering into the nanoscale region, the impact of quantum physics needs to be considered. In the past, the quantum size effect on linear material properties has been studied extensively. However, the nonlinear aspects have not been explored much so far. On the other hand, much effort has been put into the field of integrated nonlinear optics and a medium with large nonlinearity is desirable. Here we study the optical nonlinear properties of a nanometre scale gold quantum well by using the z-scan method and nonlinear spectrum broadening technique. The quantum size effect results in a giant optical Kerr susceptibility, which is four orders of magnitude higher than the intrinsic value of bulk gold and several orders larger than traditional nonlinear media. Such high nonlinearity enables efficient nonlinear interaction within a microscopic footprint, making quantum metallic films a promising candidate for integrated nonlinear optical applications.

  2. The moderating effects of skin color and ethnic identity affirmation on suicide risk among low-SES African American women

    PubMed Central

    Perry, Brea L.; Stevens-Watkins, Danelle; Oser, Carrie B.

    2012-01-01

    This study examined the influence of concurrent racism and sexism experiences (i.e. gendered racism) on African American women’s suicidal ideation and behavior in the context of disadvantaged socioeconomic status. Drawing on a stress process framework, the moderating effects of ethnic identity and skin color were explored using multiple regression analyses. Data were from 204 low-income African American women in the B-WISE (Black Women in a Study of Epidemics) project. Findings suggested that experiencing gendered racism significantly increased these women’s risk for suicidal ideation or behavior, though only among women with medium or dark skin color. Also, having strong ethnic identity buffered the harmful effects of gendered racism. The moderating properties of skin color and ethnic identity affirmation likely operate through psychosocial pathways, blocking internalization of negative stereotypes and reducing the level of distress experienced in response to gendered racism. PMID:23459264

  3. Elucidating the ensemble of functionally-relevant transitions in protein systems with a robotics-inspired method.

    PubMed

    Molloy, Kevin; Shehu, Amarda

    2013-01-01

    Many proteins tune their biological function by transitioning between different functional states, effectively acting as dynamic molecular machines. Detailed structural characterization of transition trajectories is central to understanding the relationship between protein dynamics and function. Computational approaches that build on the Molecular Dynamics framework are in principle able to model transition trajectories at great detail but also at considerable computational cost. Methods that delay consideration of dynamics and focus instead on elucidating energetically-credible conformational paths connecting two functionally-relevant structures provide a complementary approach. Effective sampling-based path planning methods originating in robotics have been recently proposed to produce conformational paths. These methods largely model short peptides or address large proteins by simplifying conformational space. We propose a robotics-inspired method that connects two given structures of a protein by sampling conformational paths. The method focuses on small- to medium-size proteins, efficiently modeling structural deformations through the use of the molecular fragment replacement technique. In particular, the method grows a tree in conformational space rooted at the start structure, steering the tree to a goal region defined around the goal structure. We investigate various bias schemes over a progress coordinate for balance between coverage of conformational space and progress towards the goal. A geometric projection layer promotes path diversity. A reactive temperature scheme allows sampling of rare paths that cross energy barriers. Experiments are conducted on small- to medium-size proteins of length up to 214 amino acids and with multiple known functionally-relevant states, some of which are more than 13Å apart of each-other. Analysis reveals that the method effectively obtains conformational paths connecting structural states that are significantly different. A detailed analysis on the depth and breadth of the tree suggests that a soft global bias over the progress coordinate enhances sampling and results in higher path diversity. The explicit geometric projection layer that biases the exploration away from over-sampled regions further increases coverage, often improving proximity to the goal by forcing the exploration to find new paths. The reactive temperature scheme is shown effective in increasing path diversity, particularly in difficult structural transitions with known high-energy barriers.

  4. Effect of viscous dissipation and radiation in an annular cone

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

    Ahmed, N. J. Salman; Kamangar, Sarfaraz; Khan, T. M. Yunus, E-mail: yunus.tatagar@gmail.com

    The viscous dissipation is an effect due to which heat is generated inside the medium. The presence of radiation further complicates the heat transfer behavior inside porous medium. The present paper discusses the combined effect of viscous dissipation and radiation inside a porous medium confined in an annular cone with inner radius r{sub i}. The viscous dissipation and radiation terms are included in the energy equation thereby solving the coupled momentum and energy equations with the help of finite element method. The results are presented in terms of isothermal and streamline indicating the thermal and fluid flow behavior of porousmore » medium. It is found that the combination of viscous dissipation and radiation parameter and the cone angle has significant effect on the heat transfer and fluid flow behavior inside the porous medium. The fluid velocity is found to increase with the increase in Raleigh number.« less

  5. Direct Demonstration of the Concept of Unrestricted Effective-Medium Approximation

    NASA Technical Reports Server (NTRS)

    Mishchenko, Michael I.; Dlugach, Zhanna M.; Zakharova, Nadezhda T.

    2014-01-01

    The modified unrestricted effective-medium refractive index is defined as one that yields accurate values of a representative set of far-field scattering characteristics (including the scattering matrix) for an object made of randomly heterogeneous materials. We validate the concept of the modified unrestricted effective-medium refractive index by comparing numerically exact superposition T-matrix results for a spherical host randomly filled with a large number of identical small inclusions and Lorenz-Mie results for a homogeneous spherical counterpart. A remarkable quantitative agreement between the superposition T-matrix and Lorenz-Mie scattering matrices over the entire range of scattering angles demonstrates unequivocally that the modified unrestricted effective-medium refractive index is a sound (albeit still phenomenological) concept provided that the size parameter of the inclusions is sufficiently small and their number is sufficiently large. Furthermore, it appears that in cases when the concept of the modified unrestricted effective-medium refractive index works, its actual value is close to that predicted by the Maxwell-Garnett mixing rule.

  6. Image Processing for Teaching.

    ERIC Educational Resources Information Center

    Greenberg, R.; And Others

    1993-01-01

    The Image Processing for Teaching project provides a powerful medium to excite students about science and mathematics, especially children from minority groups and others whose needs have not been met by traditional teaching. Using professional-quality software on microcomputers, students explore a variety of scientific data sets, including…

  7. X-ray optics for WHIMex: the Warm Hot Intergalactic Medium Explorer

    NASA Astrophysics Data System (ADS)

    Cash, W.; McEntaffer, R.; Zhang, W.; Casement, S.; Lillie, C.; Schattenburg, M.; Bautz, M.; Holland, A.; Tsunemi, H.; O'Dell, S.

    2011-09-01

    The x-ray astronomy community has never flown a celestial source spectrograph that can resolve natural line widths in absorption the way the ultraviolet community did with OAO-3 Copernicus back in 1972. Yet there is important science to be mined there, and right now, the large flagship missions like the International X-ray Observatory are not progressing toward launch. WHIMEx is an Explorer concept proposed earlier this year to open up that science regime in the next few years. The concept features a modified off-plane grating spectrograph design that will support high resolution (λ/δλ ~ 4000) in the soft x-ray band with a high packing density that will enable a modest cost space mission. We discuss the design and capabilities for the WHIMEx mission. Its prime science goal is detecting high temperature oxygen in the Intergalactic Medium, but it has a broad range of science potential cutting across all of x-ray astronomy and should give us a new window on the Universe.

  8. Virtual art revisited

    NASA Astrophysics Data System (ADS)

    Ruzanka, S.

    2014-02-01

    Virtual reality art at the turn of the millenium saw an explosion of creative exploration around this nascent technoloy. Though VR art has much in common with media art in general, the affordances of the technology gave rise to unique experiences, discourses, and artistic investigations. Women artists were at the forefront of the medium, shaping its aesthetic and technical development, and VR fostered a range of artistic concerns and experimentation that was largely distinct from closely related forms such as digital games. Today, a new wave of consumer technologies including 3D TV's, gestural and motion tracking interfaces, and headmount displays as viable, low-cost gaming peripherals drives a resurgence in interest in VR for interactive art and entertainment. Designers, game developers, and artists working with these technologies are in many cases discovering them anew. This paper explores ways of reconnecting this current moment in VR with its past. Can the artistic investigations begun in previous waves of VR be continued? How do the similarities and differences in contexts, communities, technologies, and discourses affect the development of the medium?

  9. An eastward propagating compressional Pc 5 wave observed by AMPTE/CCE in the postmidnight sector. [Active Magnetospheric Particle Tracer Explorers

    NASA Technical Reports Server (NTRS)

    Takahashi, K.; Mcentire, R. W.; Zanetti, L. J.; Lopez, R. E.; Kistler, L. M.

    1987-01-01

    This paper presents a detailed analysis of a compressional Pc 5 wave observed in the postmidnight sector on July 21, 1986, using data from the magnetometer, the charge-energy-mass spectrometer, and the medium-energy particle analyzer aboard the AMPTE/Charge Composition Explorer (CCE) spacecraft. The Pc 5 wave exhibited harmonically related transverse and compressional magnetic oscillations, modulation of the flux of medium energy protons, and a large azimuthal wave number, i.e., properties that are similar to those of compressional Pc5 waves observed previously at geostationary orbit. The unique observations recorded by the AMPTE/CCE included the occurrence of the wave in the postmidnight sector, its sunward propagation with respect to the spacecraft, and the left-handed polarization of the perturbed magnetic field. In spite of the morphological uniqueness observed, the excitation of the July 21 event is considered to be due to the same type of instability as operates at geostationary orbit.

  10. Geochemistry and exploration criteria for epithermal cinnabar and stibnite vein deposits in the Kuskokwim River region, southwestern Alaska

    USGS Publications Warehouse

    Gray, J.E.; Goldfarb, R.J.; Detra, D.E.; Slaughter, K.E.

    1991-01-01

    Cinnabar- and stibnite-bearing epithermal vein deposits are found throughout the Kuskokwim River region of southwestern Alaska. A geochemical orientation survey was carried out around several of these epithermal lodes to obtain information for planning regional geochemical surveys and to develop procedures which maximize the anomaly: threshold contrast of the deposits. Stream sediment, heavy-mineral concentrate, stream water, and vegetation samples were collected in drainages surrounding the Red Devil, Cinnabar Creek, White Mountain, Rhyolite, and Mountain Top deposits. Three sediment size fractions; nonmagnetic, paramagnetic and magnetic splits of the concentrate samples; stream waters; and the vegetation samples were analyzed for multi-element suites by a number of different chemical procedures. Nonmagnetic, heavy-mineral concentrates were also examined microscopically to identify their mineralogy. Results confirm Hg, Sb and As concentrations in minus-80-mesh stream sediments as effective pathfinder elements in exploration for epithermal cinnabar and stibnite deposits. Coarser-grained sediments are much less effective in the exploration for these deposits. Concentrations greater than 3 ppm Hg, 1 ppm Sb, and 15 ppm As in the minus-80-mesh stream sediment, regardless of the host lithology, are indicative of upstream cinnabar-stibnite deposits. Gold, Ag and base metals in the stream sediments are ineffective pathfinders for this epithermal deposit type. Collection of heavy-mineral concentrates provides little advantage in the exploration for these mineral deposits. Antimony and As dispersion patterns downstream from mineralized areas are generally more restricted in the concentrates than those in the stream sediments. Anomalous placer cinnabar observed in the concentrates has a similar spatial distribution pattern as anomalous Hg and Sb in corresponding sediments. Stream waters are less effective than the stream sediments or heavy-mineral concentrates, and vegetation is an ineffective geochemical sample medium in exploration for this deposit type. ?? 1991.

  11. Evaluating in Vitro Culture Medium of Gut Microbiome with Orthogonal Experimental Design and a Metaproteomics Approach.

    PubMed

    Li, Leyuan; Zhang, Xu; Ning, Zhibin; Mayne, Janice; Moore, Jasmine I; Butcher, James; Chiang, Cheng-Kang; Mack, David; Stintzi, Alain; Figeys, Daniel

    2018-01-05

    In vitro culture based approaches are time- and cost-effective solutions for rapidly evaluating the effects of drugs or natural compounds against microbiomes. The nutritional composition of the culture medium is an important determinant for effectively maintaining the gut microbiome in vitro. This study combines orthogonal experimental design and a metaproteomics approach to obtaining functional insights into the effects of different medium components on the microbiome. Our results show that the metaproteomic profile respond differently to medium components, including inorganic salts, bile salts, mucin, and short-chain fatty acids. Multifactor analysis of variance further revealed significant main and interaction effects of inorganic salts, bile salts, and mucin on the different functional groups of gut microbial proteins. While a broad regulating effect was observed on basic metabolic pathways, different medium components also showed significant modulations on cell wall, membrane, and envelope biogenesis and cell motility related functions. In particular, flagellar assembly related proteins were significantly responsive to the presence of mucin. This study provides information on the functional influences of medium components on the in vitro growth of microbiome communities and gives insight on the key components that must be considered when selecting and optimizing media for culturing ex vivo microbiotas.

  12. Effective medium model for a granular monolayer on an elastic substrate

    NASA Astrophysics Data System (ADS)

    Maznev, Alexei

    Effective medium models have been shown to work well in describing experimental observations of the interaction of surface Rayleigh waves with contact vibrations of a monolayer of microspheres . However, these models contain intrinsic conceptual problems: for example, the local displacement of the substrate at the contact point is equated to the effective medium average value of the surface displacement. I will present a rigorous derivation of the effective medium model for a random arrangement of mass-spring oscillators on an elastic half-space using elastodynamic surface Green's function formalism. We will see that the model equating the local surface displacement to the effective medium displacement is indeed valid if the spring constant of the oscillators is modified to include the stiffness of the contact calculated in the quasistatic approximation. In the case of contact vibrations of microspheres, this means using the spring constant calculated using the Hertzian contact model. Thus the results obtained in the prior work were correct despite the apparent inconsistencies in the model. The presented analysis will provide a solid foundation for effective medium models used to describe dynamics of microparticle arrays adhered to a solid substrate. This work was supported by the U. S. Army Research Office through the Institute for Soldier Nanotechnologies under Grant W911NF-13-D-0001.

  13. Recirculating cardiac delivery of AAV2/1SERCA2a improves myocardial function in an experimental model of heart failure in large animals.

    PubMed

    Byrne, M J; Power, J M; Preovolos, A; Mariani, J A; Hajjar, R J; Kaye, D M

    2008-12-01

    Abnormal excitation-contraction coupling is a key pathophysiologic component of heart failure (HF), and at a molecular level reduced expression of the sarcoplasmic reticulum (SR) Ca(2+) ATPase (SERCA2a) is a major contributor. Previous studies in small animals have suggested that restoration of SERCA function is beneficial in HF. Despite this promise, the means by which this information might be translated into potential clinical application remains uncertain. Using a recently established cardiac-directed recirculating method of gene delivery, we administered adeno-associated virus 2 (AAV2)/1SERCA2a to sheep with pacing-induced HF. We explored the effects of differing doses of AAV2/1SERCA2a (low 1 x 10(10) d.r.p.; medium 1 x 10(12) d.r.p. and high 1 x 10(13) d.r.p.) in conjunction with an intra-coronary delivery group (2.5 x 10(13) d.r.p.). At the end of the study, haemodynamic, echocardiographic, histopathologic and molecular biologic assessments were performed. Cardiac recirculation delivery of AAV2/1SERCA2a elicited a dose-dependent improvement in cardiac performance determined by left ventricular pressure analysis, (+d P/d t(max); low dose -220+/-70, P>0.05; medium dose 125+/-53, P<0.05; high dose 287+/-104, P<0.05) and echocardiographically (fractional shortening: low dose -3+/-2, P>0.05; medium dose 1+/-2, P>0.05; high dose 6.5+/-3.9, P<0.05). In addition to favourable haemodynamic effects, brain natriuretic peptide expression was reduced consistent with reversal of the HF molecular phenotype. In contrast, direct intra-coronary infusion did not elicit any effect on ventricular function. As such, AAV2/1SERCA2a elicits favourable functional and molecular actions when delivered in a mechanically targeted manner in an experimental model of HF. These observations lay a platform for potential clinical translation.

  14. Inhibition effects of chlorogenic acid on benign prostatic hyperplasia in mice.

    PubMed

    Huang, Ya; Chen, Huaguo; Zhou, Xin; Wu, Xingdong; Hu, Enming; Jiang, Zhengmeng

    2017-08-15

    This study aimed to evaluate the inhibitory effects and explore mechanisms of chlorogenic acid against testosterone-induced benign prostatic hyperplasia (BPH) in mice. Benign prostatic hyperplasia model was induced in experimental groups by daily subcutaneous injections of testosterone propionate (7.5mg/kg/d) consecutively for 14 d. A total of 60 mice were randomly divided into six groups: (Group 1) normal control group, (Group 2) benign prostatic hyperplasia model control group, (Group 3) benign prostatic hyperplasia mice treated with finasteride at a dose of 1mg/kg, (Group 4) benign prostatic hyperplasia mice treated with chlorogenic acid at dose levels of 0.8mg/kg (low dose group), (Group 5) benign prostatic hyperplasia mice treated with chlorogenic acid at dose levels of 1.6mg/kg (medium dose group) and (Group 6) benign prostatic hyperplasia mice treated with chlorogenic acid at dose levels of 3.2mg/kg (high dose group). Animals were sacrificed on the scheduled termination, pick out the eyeball to get blood, then prostates were weighed and prostatic index were determined. Then the serum acid phosphatase (ACP), prostatic acid phosphatase (PACP) and typeⅡ5-alpha-reductase (SRD5A2) levels were measured and observed morphological changes of the prostate. Comparing with benign prostatic hyperplasia model group, the high and medium dose of chlorogenic acid could significantly reduce prostate index and levels of acid phosphatase, prostatic acid phosphatase and typeⅡ5-alpha-reductase (P<0.05 or P<0.01). These findings were supported by histopathological observations of prostate tissues. Histopathological examination also indicated that chlorogenic acid treatment at the high and medium doses inhibited testosterone-induced prostatic hyperplasia. The results indicated that chlorogenic acid exhibited restraining effect on benign prostatic hyperplasia model animals, and its mechanism might be related to inhibit typeⅡ5-alpha reductase activity. Copyright © 2017. Published by Elsevier B.V.

  15. The behavior of enclosed-type connection of drill pipes during percussive drilling

    NASA Astrophysics Data System (ADS)

    Shadrina, A.; Saruev, L.

    2015-11-01

    Percussion drilling is the efficient method to drill small holes (≥ 70 mm) in medium- hard and harder rocks. The existing types of drill strings for geological explorations are not intended for strain wave energy transfer. The description of the improved design of the drill string having enclosed-type nipple connections is given in this paper presents. This nipple connection is designed to be used in drilling small exploration wells with formation sampling. Experimental findings prove the effectiveness of the enclosed nipple connection in relation to the load distribution in operation. The paper presents research results of the connection behavior under quasistatic loading (compression-tension). Loop diagrams are constructed and analyzed in force-displacement coordinates. Research results are obtained for shear stresses occurred in the nipple connection. A mechanism of shear stress distribution is described for the wave strain propagation over the connecting element. It is shown that in the course of operation the drill pipe tightening reduces the shear stress three times.

  16. Space activities in 2009/2010

    NASA Astrophysics Data System (ADS)

    Pagkratis, Spyros

    2011-09-01

    The global financial crisis of 2008 has created an economic environment unfavourable to public and corporate economic activity alike, which could not have left space activities unaffected. However, the effects of the crisis upon the space sector have been so far less damaging than anticipated. The following paper presents recent developments in the field of space policies, institutional budgets and commercial activity worldwide, in an effort to improve the understanding of the new trends in commercial and public space activities. It particularly explores the strategies followed by space stakeholders in different countries and regions in order to pursue their planned space programmes in view of difficult financial conditions. Finally, it highlights the differences in the outlook of space activities between established and emerging space-faring nations and attempts to explore their medium-term consequences on an international level. For this purpose, it was based on research conducted in the framework of a recent ESPI report on "Space Policies, Issues and trends in 2009/2010".

  17. Exploring the Media Mix during IT-Offshore Project

    NASA Astrophysics Data System (ADS)

    Wende, Erik; Schwabe, Gerhard; Philip, Tom

    Offshore outsourced IT projects continue to gain relevance in the globalized world scenario. The temporal, geographical and cultural distances involved during the development of software between distributed team members result in communication challenges. As software development involves the coding of knowledge, the management of knowledge and its transfer remain critical for the success of the project. For effective knowledge transfer between geographically dispersed teams the ongoing selection of communication medium or the media channel mix becomes highly significant. Although there is an abundance of theory dealing with knowledge transfer and media channel selection during offshore outsourcing projects, the specific role of cultural differences in the media mix is often overlooked. As a first step to rectify this, this paper presents an explorative outsourcing case study with emphasis on the chosen media channels and the problems that arose from differences in culture. The case study is analyzed in light of several theoretical models. Finally the paper presents the idea of extending the Media Synchonicity theory with cultural factors.

  18. A group's physical attractiveness is greater than the average attractiveness of its members: the group attractiveness effect.

    PubMed

    van Osch, Yvette; Blanken, Irene; Meijs, Maartje H J; van Wolferen, Job

    2015-04-01

    We tested whether the perceived physical attractiveness of a group is greater than the average attractiveness of its members. In nine studies, we find evidence for the so-called group attractiveness effect (GA-effect), using female, male, and mixed-gender groups, indicating that group impressions of physical attractiveness are more positive than the average ratings of the group members. A meta-analysis on 33 comparisons reveals that the effect is medium to large (Cohen's d = 0.60) and moderated by group size. We explored two explanations for the GA-effect: (a) selective attention to attractive group members, and (b) the Gestalt principle of similarity. The results of our studies are in favor of the selective attention account: People selectively attend to the most attractive members of a group and their attractiveness has a greater influence on the evaluation of the group. © 2015 by the Society for Personality and Social Psychology, Inc.

  19. Exploring nursing e-learning systems success based on information system success model.

    PubMed

    Chang, Hui-Chuan; Liu, Chung-Feng; Hwang, Hsin-Ginn

    2011-12-01

    E-learning is thought of as an innovative approach to enhance nurses' care service knowledge. Extensive research has provided rich information toward system development, courses design, and nurses' satisfaction with an e-learning system. However, a comprehensive view in understanding nursing e-learning system success is an important but less focused-on topic. The purpose of this research was to explore net benefits of nursing e-learning systems based on the updated DeLone and McLean's Information System Success Model. The study used a self-administered questionnaire to collected 208 valid nurses' responses from 21 of Taiwan's medium- and large-scale hospitals that have implemented nursing e-learning systems. The result confirms that the model is sufficient to explore the nurses' use of e-learning systems in terms of intention to use, user satisfaction, and net benefits. However, while the three exogenous quality factors (system quality, information quality, and service quality) were all found to be critical factors affecting user satisfaction, only information quality showed a direct effect on the intention to use. This study provides useful insights for evaluating nursing e-learning system qualities as well as an understanding of nurses' intentions and satisfaction related to performance benefits.

  20. Exploration of the Kinetics of Toehold-Mediated Strand Displacement via Plasmon Rulers.

    PubMed

    Li, Mei-Xing; Xu, Cong-Hui; Zhang, Nan; Qian, Guang-Sheng; Zhao, Wei; Xu, Jing-Juan; Chen, Hong-Yuan

    2018-04-24

    DNA/RNA strand displacement is one of the most fundamental reactions in DNA and RNA circuits and nanomachines. In this work, we reported an exploration of the dynamic process of the toehold-mediated strand displacement via core-satellite plasmon rulers at the single-molecule level. Applying plasmon rulers with unlimited lifetime, single-strand displacement triggered by the invader that resulted in stepwise leaving of satellite from the core was continuously monitored by changes of scattering signal for hours. The kinetics of strand displacement in vitro with three different toehold lengths have been investigated. Also, the study revealed the difference in the kinetics of strand displacement between DNA/RNA and DNA/DNA duplexes. For the kinetics study in vivo, influence from the surrounding medium has been evaluated using both phosphate buffer and cell lysate. Applying core-satellite plasmon rulers with high signal/noise ratio, kinetics study in living cells proceeded for the first time, which was not possible by conventional methods with a fluorescent reporter. The plasmon rulers, which are flexible, easily constructed, and robust, have proven to be effective tools in exploring the dynamical behaviors of biochemical reactions in vivo.

  1. Exploring the "Sharkcano": Biogeochemical observations of the Kavachi submarine volcano (Solomon Islands) using simple, cost-effective methods.

    NASA Astrophysics Data System (ADS)

    Phillips, B. T.; Albert, S.; Carey, S.; DeCiccio, A.; Dunbabin, M.; Flinders, A. F.; Grinham, A. R.; Henning, B.; Howell, C.; Kelley, K. A.; Scott, J. J.

    2015-12-01

    Kavachi is a highly active undersea volcano located in the Western Province of the Solomon Islands, known for its frequent phreatomagmatic eruptions and ephemeral island-forming activity. The remote location of Kavachi and its explosive behavior has restricted scientific exploration of the volcano, limiting observations to surface imagery and peripheral water-column data. An expedition to Kavachi in January 2015 was timed with a rare lull in volcanic activity, allowing for observation of the inside of Kavachi's caldera and its flanks. Here we present medium-resolution bathymetry of the main peak paired with benthic imagery, petrologic analysis of samples from the caldera rim, measurements of gas flux over the main peak, and hydrothermal plume structure data. A second peak was discovered to the Southwest of the main cone and displayed evidence of diffuse-flow venting. Populations of gelatinous animals, small fish, and sharks were observed inside the active crater, raising new questions about the ecology of active submarine volcanoes. Most equipment used in this study was lightweight, relatively low-cost, and deployed using small boats; these methods may offer developing nations an economic means to explore deep-sea environments within their own territorial waters.

  2. Scale-dependent effects on wave propagation in magnetically affected single/double-layered compositionally graded nanosize beams

    NASA Astrophysics Data System (ADS)

    Ebrahimi, Farzad; Barati, Mohammad Reza

    2018-04-01

    This article deals with the wave propagation analysis of single/double layered functionally graded (FG) size-dependent nanobeams in elastic medium and subjected to a longitudinal magnetic field employing nonlocal elasticity theory. Material properties of nanobeam change gradually according to the sigmoid function. Applying an analytical solution, the acoustical and optical dispersion relations are explored for various wave number, nonlocality parameter, material composition, elastic foundation constants, and magnetic field intensity. It is found that frequency and phase velocity of waves propagating in S-FGM nanobeam are significantly affected by these parameters. Also, presence of cut-off and escape frequencies in wave propagation analysis of embedded S-FGM nanobeams is investigated.

  3. High-Contrast Gratings based Spoof Surface Plasmons

    NASA Astrophysics Data System (ADS)

    Li, Zhuo; Liu, Liangliang; Xu, Bingzheng; Ning, Pingping; Chen, Chen; Xu, Jia; Chen, Xinlei; Gu, Changqing; Qing, Quan

    2016-02-01

    In this work, we explore the existence of spoof surface plasmons (SSPs) supported by deep-subwavelength high-contrast gratings (HCGs) on a perfect electric conductor plane. The dispersion relation of the HCGs-based SSPs is derived analyt- ically by combining multimode network theory with rigorous mode matching method, which has nearly the same form with and can be degenerated into that of the SSPs arising from deep-subwavelength metallic gratings (MGs). Numerical simula- tions validate the analytical dispersion relation and an effective medium approximation is also presented to obtain the same analytical dispersion formula. This work sets up a unified theoretical framework for SSPs and opens up new vistas in surface plasmon optics.

  4. Avoiding Intellectual Stagnation: The Starship as an Expander of Minds

    NASA Astrophysics Data System (ADS)

    Crawford, Ian A.

    2014-06-01

    Interstellar exploration will advance human knowledge and culture in multiple ways. Scientifically, it will advance our understanding of the interstellar medium, stellar astrophysics, planetary science and astrobiology. In addition, significant societal and cultural benefits will result from a programme of interstellar exploration and colonisation. Most important will be the cultural stimuli resulting from expanding the horizons of human experience, and increased opportunities for the spread and diversification of life and culture through the Galaxy. Ultimately, a programme of interstellar exploration may be the only way for human (and post-human) societies to avoid the intellectual stagnation predicted for the `end of history'.

  5. The effect of environmental pH on polymeric transfection efficiency.

    PubMed

    Kang, Han Chang; Samsonova, Olga; Kang, Sun-Woong; Bae, You Han

    2012-02-01

    Although polymers, polyplexes, and cells are exposed to various extracellular and intracellular pH environments during polyplex preparation and polymeric transfection, the impact of environmental pH on polymeric transfection has not yet been investigated. This study aims to understand the influence of environmental pH on polymeric transfection by modulating the pH of the transfection medium or the culture medium. Changes in the extracellular pH affected polymeric transfection by way of complex factors such as pH-induced changes in polymer characteristics (e.g., proton buffering capacity and ionization), polyplex characteristics (e.g., size, surface charge, and decomplexation), and cellular characteristics (e.g., cellular uptake, cell cycle phases, and intracellular pH environment). Notably, acidic medium delayed endocytosis, endosomal acidification, cytosolic release, and decomplexation of polyplexes, thereby negatively affecting gene expression. However, acidic medium inhibited mitosis and reduced dilution of gene expression, resulting in increased transfection efficiency. Compared to pH 7.4 medium, acidic transfection medium reduced gene expression 1.6-7.7-fold whereas acidic culture medium enhanced transfection efficiency 2.1-2.6-fold. Polymeric transfection was affected more by the culture medium than by the transfection medium. Understanding the effects of extracellular pH during polymeric transfection may stimulate new strategies for determining effective and safe polymeric gene carriers. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Organic reductants based leaching: A sustainable process for the recovery of valuable metals from spent lithium ion batteries.

    PubMed

    Chen, Xiangping; Guo, Chunxiu; Ma, Hongrui; Li, Jiazhu; Zhou, Tao; Cao, Ling; Kang, Duozhi

    2018-05-01

    It is significant to recover metal values from spent lithium ion batteries (LIBs) for the alleviation or prevention of potential risks towards environmental pollution and public health, as well as for the conservation of valuable metals. Herein a hydrometallurgical process was proposed to explore the possibility for the leaching of different metals from waste cathodic materials (LiCoO 2 ) of spent LIBs using organics as reductant in sulfuric acid medium. According to the leaching results, about 98% Co and 96% Li can be leached under the optimal experimental conditions of reaction temperature - 95 °C, reaction time - 120 min, reductive agent dosage - 0.4 g/g, slurry density - 25 g/L, concentration of sulfuric acid-3 mol/L in H 2 SO 4  + glucose leaching system. Similar results (96% Co and 100% Li) can be obtained in H 2 SO 4  + sucrose leaching system under optimized leaching conditions. Despite a complete leaching of Li (∼100%), only 54% Co can be dissolved in the H 2 SO 4  + cellulose leaching system under optimized leaching conditions. Finally, different characterization methods, including UV-Vis, FT-IR, SEM and XRD, were employed for the tentative exploration of reductive leaching reactions using organic as reductant in sulfuric acid medium. All the leaching and characterization results confirm that both glucose and sucrose are effective reductants during leaching, while cellulose should be further degraded to organics with low molecular weights to achieve a satisfactory leaching performance. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Low density of neutral hydrogen and helium in the local interstellar medium: Extreme Ultraviolet Explorer photometry of the Lyman continuum of the hot white dwarfs MCT 0501-2858, MCT 0455-2812, HZ 43, and GD 153

    NASA Technical Reports Server (NTRS)

    Vennes, Stephane; Dupuis, Jean; Bowyer, Stuart; Fontaine, Gilles; Wiercigroch, Alexandria; Jelinsky, Patrick; Wesemael, Francois; Malina, Roger

    1994-01-01

    The first comprehensive sky survey of the extreme ultraviolet (EUV) spectral range performed by the Extreme Ultraviolet Explorer (EUVE) has uncovered a handful of very bright sources at wavelengths longer than the He I 504 A photoionization edge. Among these objects are four white dwarfs with exceptionally low interstellar medium (ISM) column densities along the line of sight. Analysis of EUV photometry of the He-rich DO white dwarf MCT 0501-2858 and the H-rich DA white dwarf MCT 0455-2812 along one line of sight and of the DA white dwarfs HZ 43 and GD 153 near the north Galactic pole indicates that the overall minimum column density of the neutral material centered on the Sun is N(H I) = 0.5-1.0 x 10(exp 18)/sq cm. In the case of MCT 0501-2858, EUV photometric measurements provide a clear constraint to the effective temperature (60,000-70,000 K). Given these neutral hydrogen columns, the actual contribution to the density of neutral species from the immediate solar environment (the 'local fluff') would only cover a distance of approximately equals 2-3 pc (assuming an average density n(H I) = 0.1/cu cm) leaving these lines of sight almost entirely within the hot phase of the ISM. A preliminary examination of the complete EUVE long-wavelength survey indicates that these lines of sight are exceptional and set a minimum column density in the solar environment.

  8. In vitro propagation of Cymbidium goeringii Reichenbach fil. through direct adventitious shoot regeneration.

    PubMed

    Park, Han Yong; Kang, Kyung Won; Kim, Doo Hwan; Sivanesan, Iyyakkannu

    2018-03-01

    The influence of 2,4-dichlorophenoxyacetic acid (2,4-D), benzyladenine (BA), and thidiazuron (TDZ) on direct rhizome induction and shoot formation from rhizome explants of Cymbidium goeringii was explored. Rhizome segments obtained from in vitro seed cultures of C. goeringii were placed on Murashige and Skoog (MS) medium incorporated with 5, 10, 20, or 40 µM 2,4-D and 1, 2, 4, or 8 µM BA or TDZ alone or in combination with 20 µM 2,4-D. The explants developed only rhizomes on MS medium with or without 2,4-D. The highest percent of rhizome formation (100%) was obtained on MS medium incorporated with 20 μM of 2,4-D. The morphology and number of rhizomes varied with the level of 2,4-D in the medium. Direct adventitious shoot formation was achieved on medium incorporated with BA or TDZ. The adventitious shoots produced per explant significantly increased with the supplementation of 2,4-D to cytokinin-containing medium. The highest mean of 21.8 ± 1.8 shoot buds per rhizome segment was obtained in medium fortified with 20 μM 2,4-D and 2 μM TDZ. The greatest percent of root induction (100%) and the mean of 5.3 ± 1.1 roots per shoot were achieved on ½ MS medium incorporated with 2 μM of α-naphthaleneacetic acid. About 97% of the in vitro-produced plantlets acclimatized in the greenhouse. An efficient in vitro propagation protocol was thus developed for C. goeringii using rhizome explants.

  9. Modeling of layered anisotropic composite material based on effective medium theory

    NASA Astrophysics Data System (ADS)

    Bao, Yang; Song, Jiming

    2018-04-01

    In this paper, we present an efficient method to simulate multilayered anisotropic composite material with effective medium theory. Effective permittivity, permeability and orientation angle for a layered anisotropic composite medium are extracted with this equivalent model. We also derive analytical expressions for effective parameters and orientation angle with low frequency (LF) limit, which will be shown in detail. Numerical results are shown in comparing extracted effective parameters and orientation angle with analytical results from low frequency limit. Good agreements are achieved to demonstrate the accuracy of our efficient model.

  10. Comparing Universal Lynch Syndrome Tumor Screening Programs to Evaluate Associations Between Implementation Strategies and Patient Follow-through

    PubMed Central

    Cragun, Deborah; DeBate, Rita D.; Vadaparampil, Susan T.; Baldwin, Julie; Hampel, Heather; Pal, Tuya

    2014-01-01

    Purpose Universal tumor screening (UTS) for all colorectal cancer (CRC) patients can improve the identification of Lynch syndrome, the most common cause of hereditary CRC. This multiple-case study explored how variability in UTS procedures influence patient follow-through (PF) with germline testing after a screen-positive result. Methods Data were obtained through web-based surveys and telephone interviews with institutional informants. Institutions were categorized as Low-PF (≤10% underwent germline testing), Medium-PF (11–40%), or High-PF (>40%). To identify implementation procedures (i.e., conditions) unique High-PF institutions, qualitative comparative analysis was performed. Results Twenty-one informants from fifteen institutions completed surveys and/or interviews. Conditions present among all five High-PF institutions included: 1) disclosure of screen-positive results to patients by genetic counselors (GCs); and 2) GCs either facilitate physician referrals to genetics or eliminated the need for referrals. Although both of these High-PF conditions were present among two Medium-PF institutions, automatic reflex testing was lacking and difficulty contacting screen-positive patients was a barrier. The three remaining Medium-PF and five Low-PF institutions lacked High-PF conditions. Conclusion Methods for streamlining UTS procedures, incorporating a high level of involvement of GCs in results tracking and communication, and reducing barriers to patient contact are reviewed within a broader discussion on maximizing the effectiveness and public health impact of UTS. PMID:24651603

  11. Effect of bicarbonate concentration on aerobic growth of campylobacter in a fumarate-pyruvate medium

    USDA-ARS?s Scientific Manuscript database

    The purpose of the present study was to examine the effect of sodium bicarbonate (NaHCO3) concentration on aerobic growth of Campylobacter in a fumarate-pyruvate medium. Fumarate-pyruvate broth medium was supplemented with 0.00 to 0.10% NaHCO3 and inoculated with Campylobacter coli 33559, Campyloba...

  12. Observations of the interstellar medium with IUE

    NASA Technical Reports Server (NTRS)

    Jenkins, E. B.

    1981-01-01

    Limitations of the International Ultraviolet Explorer (IUE) are discussed, as well as improved powers of research in these areas: (1) Si and C IV doublet absorptions in the high dispersion stellar spectra of distant stars; (2) observation of spectra outside the galactic plans; (3) high velocity gas.

  13. Process to Product.

    ERIC Educational Resources Information Center

    Harrison, Gary, Ed.; Mirkes, Donna Z., Ed.

    Intended for educators who direct federally funded model projects, the booklet provides a framework for special education product development. In "Making Media Decisions," G. Richman explores procedures for selecting the most appropriate medium to carry the message of a given product. The fundamental questions are addressed: what is the goal; who…

  14. (Re)visioning the Self through Art

    ERIC Educational Resources Information Center

    Henry, Sue Ellen; Verica, Joseph M.

    2015-01-01

    How can art function as a medium through which to re(view) the self and others? This article explores this central question through an interdisciplinary classroom experiment that brought theories of identity development in a multiculturalism classroom together with principles of portraiture present in an introductory drawing class. Interview…

  15. Medium Effects on Freeze-Out of Light Clusters at NICA Energies

    NASA Astrophysics Data System (ADS)

    Röpke, G.; Blaschke, D.; Ivanov, Yu. B.; Karpenko, Iu.; Rogachevsky, O. V.; Wolter, H. H.

    2018-05-01

    We estimate the chemical freeze-out of light nuclear clusters for NICA energies of above 2 A GeV. On the one hand we use results from the low energy domain of about 35 A MeV, where medium effects have been shown to be important to explain experimental results. On the high energy side of LHC energies the statistical model without medium effects has provided results for the chemical freeze-out. The two approaches extrapolated to NICA energies show a discrepancy that can be attributed to medium effects and that for the deuteron/proton ratio amounts to a factor of about three. These findings underline the importance of a detailed investigation of light cluster production at NICA energies.

  16. The impact of the Sarbanes Oxley Act on auditing fees: An empirical study of the oil and gas industry

    NASA Astrophysics Data System (ADS)

    Ezelle, Ralph Wayne, Jr.

    2011-12-01

    This study examines auditing of energy firms prior and post Sarbanes Oxley Act of 2002. The research explores factors impacting the asset adjusted audit fee of oil and gas companies and specifically examines the effect of the Sarbanes Oxley Act. This research analyzes multiple year audit fees of the firms engaged in the oil and gas industry. Pooled samples were created to improve statistical power with sample sizes sufficient to test for medium and large effect size. The Sarbanes Oxley Act significantly increases a firm's asset adjusted audit fees. Additional findings are that part of the variance in audit fees was attributable to the market value of the enterprise, the number of subsidiaries, the receivables and inventory, debt ratio, non-profitability, and receipt of a going concern report.

  17. Exosomes are released by bystander cells exposed to radiation-induced biophoton signals: Reconciling the mechanisms mediating the bystander effect

    PubMed Central

    Fernandez-Palomo, Cristian; McNeill, Fiona E.; Seymour, Colin B.; Rainbow, Andrew J.; Mothersill, Carmel E.

    2017-01-01

    Objective The objective of our study was to explore a possible molecular mechanism by which ultraviolet (UV) biophotons could elicit bystander responses in reporter cells and resolve the problem of seemingly mutually exclusive mechanisms of a physical UV signal & a soluble factor-mediated bystander signal. Methods The human colon carcinoma cell line, HCT116 p53 +/+, was directly irradiated with 0.5 Gy tritium beta particles to induce ultraviolet biophoton emission. Bystander cells were not directly irradiated but were exposed to the emitted UV biophotons. Medium was subsequently harvested from UV-exposed bystander cells. The exosomes extracted from this medium were incubated with reporter cell populations. These reporter cells were then assayed for clonogenic survival and mitochondrial membrane potential with and without prior treatment of the exosomes with RNase. Results Clonogenic cell survival was significantly reduced in reporter cells incubated with exosomes extracted from cells exposed to secondarily-emitted UV. These exosomes also induced significant mitochondrial membrane depolarization in receiving reporter cells. Conversely, exosomes extracted from non-UV-exposed cells did not produce bystander effects in reporter cells. The treatment of exosomes with RNase prior to their incubation with reporter cells effectively abolished bystander effects in reporter cells and this suggests a role for RNA in mediating the bystander response elicited by UV biophotons and their produced exosomes. Conclusion This study supports a role for exosomes released from UV biophoton-exposed bystander cells in eliciting bystander responses and also indicates a reconciliation between the UV-mediated bystander effect and the bystander effect which has been suggested in the literature to be mediated by soluble factors. PMID:28278290

  18. Exosomes are released by bystander cells exposed to radiation-induced biophoton signals: Reconciling the mechanisms mediating the bystander effect.

    PubMed

    Le, Michelle; Fernandez-Palomo, Cristian; McNeill, Fiona E; Seymour, Colin B; Rainbow, Andrew J; Mothersill, Carmel E

    2017-01-01

    The objective of our study was to explore a possible molecular mechanism by which ultraviolet (UV) biophotons could elicit bystander responses in reporter cells and resolve the problem of seemingly mutually exclusive mechanisms of a physical UV signal & a soluble factor-mediated bystander signal. The human colon carcinoma cell line, HCT116 p53 +/+, was directly irradiated with 0.5 Gy tritium beta particles to induce ultraviolet biophoton emission. Bystander cells were not directly irradiated but were exposed to the emitted UV biophotons. Medium was subsequently harvested from UV-exposed bystander cells. The exosomes extracted from this medium were incubated with reporter cell populations. These reporter cells were then assayed for clonogenic survival and mitochondrial membrane potential with and without prior treatment of the exosomes with RNase. Clonogenic cell survival was significantly reduced in reporter cells incubated with exosomes extracted from cells exposed to secondarily-emitted UV. These exosomes also induced significant mitochondrial membrane depolarization in receiving reporter cells. Conversely, exosomes extracted from non-UV-exposed cells did not produce bystander effects in reporter cells. The treatment of exosomes with RNase prior to their incubation with reporter cells effectively abolished bystander effects in reporter cells and this suggests a role for RNA in mediating the bystander response elicited by UV biophotons and their produced exosomes. This study supports a role for exosomes released from UV biophoton-exposed bystander cells in eliciting bystander responses and also indicates a reconciliation between the UV-mediated bystander effect and the bystander effect which has been suggested in the literature to be mediated by soluble factors.

  19. l-Glutamine Attenuates Apoptosis Induced by Endoplasmic Reticulum Stress by Activating the IRE1α-XBP1 Axis in IPEC-J2: A Novel Mechanism of l-Glutamine in Promoting Intestinal Health

    PubMed Central

    Chen, Jiashun; Liu, Shaojuan; Yao, Kang; Yin, Yulong

    2017-01-01

    Intestinal absorption and barrier malfunctions are associated with endoplasmic reticulum stress (ERS) in the intestine. We induced ERS by exposing the intestinal porcine epithelial cell line J2 (IPEC-J2) to tunicamycin (TUNI) to explore the potential of l-glutamine to reduce ERS-induced apoptosis. Our experiments demonstrated that exposing cells to TUNI results in spontaneous ERS and encourages the upregulation of glucose-regulated protein 78 (GRP78). Prolonged TUNI-induced ERS was found to increase apoptosis mediated by C/enhancer binding protein homologous protein (CHOP), accompanied by GRP78 downregulation. Treatment with l-glutamine was found to promote cell proliferation within the growth medium but to have little effect in basic Dulbecco’s modified Eagle medium. Finally, in the milieu of TUNI-induced ERS, l-glutamine was found to maintain a high level of GRP78, alleviate CHOP-mediated apoptosis and activate the inositol requiring enzyme 1α (IRE1α)-X-box binding protein 1 (XBP1) axis. A specific inhibitor of the IRE1α-XBP1 axis reversed the protective effect of l-glutamine by blocking the expression of IRE1α/XBP1s. We propose that the functional effect of l-glutamine on intestinal health may be partly due to its modulation of ERS and CHOP-mediated apoptosis. PMID:29206200

  20. Effect of pore size of three-dimensionally ordered macroporous chitosan-silica matrix on solubility, drug release, and oral bioavailability of loaded-nimodipine.

    PubMed

    Gao, Yikun; Xie, Yuling; Sun, Hongrui; Zhao, Qinfu; Zheng, Xin; Wang, Siling; Jiang, Tongying

    2016-01-01

    To explore the effect of the pore size of three-dimensionally ordered macroporous chitosan-silica (3D-CS) matrix on the solubility, drug release, and oral bioavailability of the loaded drug. 3D-CS matrices with pore sizes of 180 nm, 470 nm, and 930 nm were prepared. Nimodipine (NMDP) was used as the drug model. The morphology, specific surface area, and chitosan mass ratio of the 3D-CS matrices were characterized before the effect of the pore size on drug crystallinity, solubility, release, and in vivo pharmacokinetics were investigated. With the pore size of 3D-CS matrix decreasing, the drug crystallinity decreased and the aqueous solubility increased. The drug release was synthetically controlled by the pore size and chitosan content of 3D-CS matrix in a pH 6.8 medium, while in a pH 1.2 medium the erosion of the 3D-CS matrix played an important role in the decreased drug release rate. The area under the curve of the drug-loaded 3D-CS matrices with pore sizes of 930 nm, 470 nm, and 180 nm was 7.46-fold, 5.85-fold, and 3.75-fold larger than that of raw NMDP respectively. Our findings suggest that the oral bioavailability decreased with a decrease in the pore size of the matrix.

  1. Nested Association Mapping of Stem Rust Resistance in Wheat Using Genotyping by Sequencing

    PubMed Central

    Rouse, Matthew N.; Tsilo, Toi J.; Macharia, Godwin K.; Bhavani, Sridhar; Jin, Yue; Anderson, James A.

    2016-01-01

    We combined the recently developed genotyping by sequencing (GBS) method with joint mapping (also known as nested association mapping) to dissect and understand the genetic architecture controlling stem rust resistance in wheat (Triticum aestivum). Ten stem rust resistant wheat varieties were crossed to the susceptible line LMPG-6 to generate F6 recombinant inbred lines. The recombinant inbred line populations were phenotyped in Kenya, South Africa, and St. Paul, Minnesota, USA. By joint mapping of the 10 populations, we identified 59 minor and medium-effect QTL (explained phenotypic variance range of 1% – 20%) on 20 chromosomes that contributed towards adult plant resistance to North American Pgt races as well as the highly virulent Ug99 race group. Fifteen of the 59 QTL were detected in multiple environments. No epistatic relationship was detected among the QTL. While these numerous small- to medium-effect QTL are shared among the families, the founder parents were found to have different allelic effects for the QTL. Fourteen QTL identified by joint mapping were also detected in single-population mapping. As these QTL were mapped using SNP markers with known locations on the physical chromosomes, the genomic regions identified with QTL could be explored more in depth to discover candidate genes for stem rust resistance. The use of GBS-derived de novo SNPs in mapping resistance to stem rust shown in this study could be used as a model to conduct similar marker-trait association studies in other plant species. PMID:27186883

  2. Analysis of dense-medium light scattering with applications to corneal tissue: experiments and Monte Carlo simulations.

    PubMed

    Kim, K B; Shanyfelt, L M; Hahn, D W

    2006-01-01

    Dense-medium scattering is explored in the context of providing a quantitative measurement of turbidity, with specific application to corneal haze. A multiple-wavelength scattering technique is proposed to make use of two-color scattering response ratios, thereby providing a means for data normalization. A combination of measurements and simulations are reported to assess this technique, including light-scattering experiments for a range of polystyrene suspensions. Monte Carlo (MC) simulations were performed using a multiple-scattering algorithm based on full Mie scattering theory. The simulations were in excellent agreement with the polystyrene suspension experiments, thereby validating the MC model. The MC model was then used to simulate multiwavelength scattering in a corneal tissue model. Overall, the proposed multiwavelength scattering technique appears to be a feasible approach to quantify dense-medium scattering such as the manifestation of corneal haze, although more complex modeling of keratocyte scattering, and animal studies, are necessary.

  3. [Culture medium based on biogas slurry and breeding of oil Chlorella].

    PubMed

    Zhao, Feng-Min; Mei, Shuai; Cao, You-Fu; Ding, Jin-Feng; Xu, Jia-Jie; Li, Shu-Jun

    2014-06-01

    The oil chlorella cultivation and biogas slurry treatment were combined. The biogas slurry provided water and nutrient for growing chlorella, at the same time, harmless treatment of biogas slurry was realized. This paper cultivated 4 species of oil chlorella in the mixed medium of biogas slurry and green algae medium (the volume ratios were 1 : 9, 1 : 3, 1 : 1 and 3 : 1, respectively), and compared their oil productivity to select the best oil chlorella species and the optimal culture medium. The results showed that, the combination of medium and chlorella species to reach the highest oil productivity was a volume ratio of 1 : 3 and the chlorella species BJ05, and the oil productivity of chlorella BJ05 was 9.20 mg x (L x d)(-1), higher than that in green algae medium [8.66 mg x (L x d)(-1)]. In mixed medium with a volume ratio of 1:3, the effect of adding different nutrients into the green algae medium on the oil productivity was examined, and the results showed that, sodium carbonate and citric acid had no negative effect on the oil productivity of chlorella BJ05. in the absence of sodium carbonate and citric acid, the oil productivity of chlorella BJ05 was 9.36 mg x (L x d)(-1), and the removal of COD (chemical oxygen demand), total nitrogen, total phosphorus and ammonia nitrogen rates were 59%, 75%, 61% and 100%, respectively. Deficiency in other nutrients had negative effect on the oil productivity. Therefore, the culture medium was further optimized to the mixed medium of biogas slurry and green algae medium with a volume ratio of 1 : 3 and without addition of sodium carbonate and citric acid.

  4. Beta1-integrin and IL-1alpha expression as bystander effect of medium from irradiated cells: the pilot study.

    PubMed

    Osterreicher, Jan; Skopek, Jirí; Jahns, Juta; Hildebrandt, Guido; Psutka, Jan; Vilasová, Zdenka; Tanner, Judith Maria; Vogt, Jürgen; Butz, Tilman

    2003-01-01

    Bystander effects have been proposed as a third action pathway of ionising radiation besides direct and indirect effects. The purpose of the study was to investigate whether expression of interleukin-1alpha (IL-1alpha) and beta1-integrin is elevated in bystander cells as a marker for bystander effects in comparison with classical markers such as the clonogenic assay, apoptosis and the presence of micronuclei. The hybrid cell line E.A. hy.926 obtained by fusion of HUVEC cells with the epithelial cell line A 459 was irradiated with 0-5 Gy. Bystander effects were established via medium transfer at 45 min and 4 h after irradiation from irradiated to nonirradiated cell populations. In order to exclude effects of the irradiated medium itself, irradiated medium only was also used for transfer to nonirradiated cells. Then, cells were fixed at 1, 2, 6, and 24 h after irradiation or medium transport and IL-1alpha and beta1-integrin were detected and evaluated. A higher number of beta1-integrin-positive cells was observed in both irradiated and bystander cell populations than in the control group at 1 and 24 h after irradiation with 1 Gy or medium transfer. Significantly higher numbers of IL-1alpha-positive cells were found at 1, 2, and 6 h after irradiation with 1 Gy or medium transfer as well as at 2 and 6 h after irradiation with 5 Gy or medium transfer. Clonogenic survival decreased dependently on the dose in irradiated cells but did not show any significant difference between the bystander cell populations and sham-irradiated cells. The irradiated medium itself did not have any effect. It is concluded that beta1-integrin and IL-1alpha expression may serve as more sensitive markers of post-irradiation responses in bystander cell populations than the classical radiobiological markers. Moreover, overexpression of beta1-integrin and IL-1alpha may induce increased susceptibility to inflammation of bystander cells.

  5. Interstellar heliospheric probe/heliospheric boundary explorer mission—a mission to the outermost boundaries of the solar system

    NASA Astrophysics Data System (ADS)

    Wimmer-Schweingruber, Robert F.; McNutt, Ralph; Schwadron, Nathan A.; Frisch, Priscilla C.; Gruntman, Mike; Wurz, Peter; Valtonen, Eino

    2009-05-01

    The Sun, driving a supersonic solar wind, cuts out of the local interstellar medium a giant plasma bubble, the heliosphere. ESA, jointly with NASA, has had an important role in the development of our current understanding of the Suns immediate neighborhood. Ulysses is the only spacecraft exploring the third, out-of-ecliptic dimension, while SOHO has allowed us to better understand the influence of the Sun and to image the glow of interstellar matter in the heliosphere. Voyager 1 has recently encountered the innermost boundary of this plasma bubble, the termination shock, and is returning exciting yet puzzling data of this remote region. The next logical step is to leave the heliosphere and to thereby map out in unprecedented detail the structure of the outer heliosphere and its boundaries, the termination shock, the heliosheath, the heliopause, and, after leaving the heliosphere, to discover the true nature of the hydrogen wall, the bow shock, and the local interstellar medium beyond. This will greatly advance our understanding of the heliosphere that is the best-known example for astrospheres as found around other stars. Thus, IHP/HEX will allow us to discover, explore, and understand fundamental astrophysical processes in the largest accessible plasma laboratory, the heliosphere.

  6. Exploring Sulfur & Argon Abundances in Planetary Nebulae as Metallicity- Indicator Surrogates for Iron in the Interstellar Medium

    NASA Astrophysics Data System (ADS)

    Kwitter, Karen B.; Henry, Richard C.

    1999-02-01

    Our primary motivation for studying S and Ar distributions in planetary nebulae (PNe) across the Galactic disk is to explore the possibility of a surrogacy between (S+Ar)/O and Fe/O for use as a metallicity indicator in the interstellar medium. The chemical history of the Galaxy is usually studied through O and Fe distributions among objects of different ages. Historically, though, Fe and O have not been measured in the same systems: Fe is easily seen in stars but hard to detect in nebulae; the reverse is true for O. We know that S and Ar abundances are not affected by PN progenitor evolution, and we therefore seek to exploit both their unaltered abundances and ease of detectability in PNe to explore their surrogacy for Fe. If proven valid, this surrogacy carries broad and important ramifications for bridging the gap between stellar and interstellar abundances in the Galaxy, and potentially beyond. Observed S/O and Ar/O gradients will also provide constraints on theoretical stellar yields of S and Ar, since they can be compared with chemical evolution models (which incorporate theoretically-predicted stellar yields, an initial mass function, and rates of star formation and infall) to help place constraints on model parameters.

  7. Identifying Organic Molecules in Space: The AstroBiology Explorer (ABE) Mission Concept

    NASA Technical Reports Server (NTRS)

    Ennico, K. A.; Sandford, S. A.; Allamandola, L.; Bregman, J.; Cohen, M.; Cruikshank, D.; Dumas, C.; Greene, T.; Hudgins, D.; Kwok, S.

    2004-01-01

    The AstroBiology Explorer (ABE) mission concept consists of a dedicated space observatory having a 60 cm class primary mirror cooled to T < 50 K equipped with medium resolution cross-dispersed spectrometers having cooled large format near- and mid-infrared detector arrays. Such a system would be capable of addressing outstanding problems in Astrochemistry and Astrophysics that are particularly relevant to Astrobiology and addressable via astronomical observation. The mission s observational program would make fundamental scientific progress in establishing the nature, distribution, formation and evolution of organic and other molecular materials in the following extra-terrestrial environments: 1) The Outflow of Dying Stars, 2) The Diffuse Interstellar Medium, 3) Dense Molecular Clouds, Star Formation Regions, and Young StellarPlanetary Systems, 4) Planets, Satellites, and Small Bodies within the Solar System, and 5 ) The Interstellar Media of Other Galaxies. ABE could make fundamental progress in all of these areas by conducting a 1 to 2 year mission to obtain a coordinated set of infrared spectroscopic observations over the 2.5-20 micron spectral range at a spectral resolution of R > 2000 of about 1500 objects including galaxies, stars, planetary nebulae, young stellar objects, and solar system objects. Keywords: Astrobiology, infrared, Explorers, interstellar organics, telescope, spectrometer, space, infrared detectors

  8. Guiding exploration in conformational feature space with Lipschitz underestimation for ab-initio protein structure prediction.

    PubMed

    Hao, Xiaohu; Zhang, Guijun; Zhou, Xiaogen

    2018-04-01

    Computing conformations which are essential to associate structural and functional information with gene sequences, is challenging due to the high dimensionality and rugged energy surface of the protein conformational space. Consequently, the dimension of the protein conformational space should be reduced to a proper level, and an effective exploring algorithm should be proposed. In this paper, a plug-in method for guiding exploration in conformational feature space with Lipschitz underestimation (LUE) for ab-initio protein structure prediction is proposed. The conformational space is converted into ultrafast shape recognition (USR) feature space firstly. Based on the USR feature space, the conformational space can be further converted into Underestimation space according to Lipschitz estimation theory for guiding exploration. As a consequence of the use of underestimation model, the tight lower bound estimate information can be used for exploration guidance, the invalid sampling areas can be eliminated in advance, and the number of energy function evaluations can be reduced. The proposed method provides a novel technique to solve the exploring problem of protein conformational space. LUE is applied to differential evolution (DE) algorithm, and metropolis Monte Carlo(MMC) algorithm which is available in the Rosetta; When LUE is applied to DE and MMC, it will be screened by the underestimation method prior to energy calculation and selection. Further, LUE is compared with DE and MMC by testing on 15 small-to-medium structurally diverse proteins. Test results show that near-native protein structures with higher accuracy can be obtained more rapidly and efficiently with the use of LUE. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Testing for post-copulatory selection for major histocompatibility complex genotype in a semi-free-ranging primate population.

    PubMed

    Setchell, Joanna M; Abbott, Kristin M; Gonzalez, Jean-Paul; Knapp, Leslie A

    2013-10-01

    A large body of evidence suggests that major histocompatibility complex (MHC) genotype influences mate choice. However, few studies have investigated MHC-mediated post-copulatory mate choice under natural, or even semi-natural, conditions. We set out to explore this question in a large semi-free-ranging population of mandrills (Mandrillus sphinx) using MHC-DRB genotypes for 127 parent-offspring triads. First, we showed that offspring MHC heterozygosity correlates positively with parental MHC dissimilarity suggesting that mating among MHC dissimilar mates is efficient in increasing offspring MHC diversity. Second, we compared the haplotypes of the parental dyad with those of the offspring to test whether post-copulatory sexual selection favored offspring with two different MHC haplotypes, more diverse gamete combinations, or greater within-haplotype diversity. Limited statistical power meant that we could only detect medium or large effect sizes. Nevertheless, we found no evidence for selection for heterozygous offspring when parents share a haplotype (large effect size), genetic dissimilarity between parental haplotypes (we could detect an odds ratio of ≥1.86), or within-haplotype diversity (medium-large effect). These findings suggest that comparing parental and offspring haplotypes may be a useful approach to test for post-copulatory selection when matings cannot be observed, as is the case in many study systems. However, it will be extremely difficult to determine conclusively whether post-copulatory selection mechanisms for MHC genotype exist, particularly if the effect sizes are small, due to the difficulty in obtaining a sufficiently large sample. © 2013 Wiley Periodicals, Inc.

  10. Optical extinction of highly porous aerosol following atmospheric freeze drying

    NASA Astrophysics Data System (ADS)

    Adler, Gabriela; Haspel, Carynelisa; Moise, Tamar; Rudich, Yinon

    2014-06-01

    Porous glassy particles are a potentially significant but unexplored component of atmospheric aerosol that can form by aerosol processing through the ice phase of high convective clouds. The optical properties of porous glassy aerosols formed from a freeze-dry cycle simulating freezing and sublimation of ice particles were measured using a cavity ring down aerosol spectrometer (CRD-AS) at 532 nm and 355 nm wavelength. The measured extinction efficiency was significantly reduced for porous organic and mixed organic-ammonium sulfate particles as compared to the extinction efficiency of the homogeneous aerosol of the same composition prior to the freeze-drying process. A number of theoretical approaches for modeling the optical extinction of porous aerosols were explored. These include effective medium approximations, extended effective medium approximations, multilayer concentric sphere models, Rayleigh-Debye-Gans theory, and the discrete dipole approximation. Though such approaches are commonly used to describe porous particles in astrophysical and atmospheric contexts, in the current study, these approaches predicted an even lower extinction than the measured one. Rather, the best representation of the measured extinction was obtained with an effective refractive index retrieved from a fit to Mie scattering theory assuming spherical particles with a fixed void content. The single-scattering albedo of the porous glassy aerosols was derived using this effective refractive index and was found to be lower than that of the corresponding homogeneous aerosol, indicating stronger relative absorption at the wavelengths measured. The reduced extinction and increased absorption may be of significance in assessing direct, indirect, and semidirect forcing in regions where porous aerosols are expected to be prevalent.

  11. Good Vibrations – Effects of Whole Body Vibration on Attention in Healthy Individuals and Individuals with ADHD

    PubMed Central

    Fuermaier, Anselm B. M.; Tucha, Lara; Koerts, Janneke; van Heuvelen, Marieke J. G.; van der Zee, Eddy A.; Lange, Klaus W.; Tucha, Oliver

    2014-01-01

    Objectives Most of the current treatment strategies of ADHD are associated with a number of disadvantages which strengthen the need for alternative or additional approaches for the treatment of ADHD. In this respect, Whole Body Vibration (WBV) might be interesting as it was found to have beneficial effects on a variety of physiological measures. The present study explored the effects of WBV on attention of healthy individuals and adults diagnosed with ADHD. Methods Eighty-three healthy individuals and seventeen adults diagnosed with ADHD participated in the study. WBV treatment was applied passively, while participants were sitting on a chair which was mounted on a vibrating platform. A repeated measure design was employed in order to explore potential effects of WBV treatment on attention within subjects. Attention (i.e. inhibitory control) was measured with a color-word interference paradigm. Results A period of two minutes of WBV treatment had significant beneficial effects of small to medium size on attention of both healthy individuals and adults with ADHD. The effect of WBV treatment on attention did not differ significantly between groups. Conclusions WBV was demonstrated to improve cognitive performance of healthy individuals as well as of individuals with ADHD. WBV treatment is relatively inexpensive and easy to apply and might therefore be of potential relevance for clinical use. The application of WBV treatment as a cognitive enhancement strategy and as a potential treatment of cognitive impairments is discussed. PMID:24587412

  12. The heliosphere's interstellar interaction: no bow shock.

    PubMed

    McComas, D J; Alexashov, D; Bzowski, M; Fahr, H; Heerikhuisen, J; Izmodenov, V; Lee, M A; Möbius, E; Pogorelov, N; Schwadron, N A; Zank, G P

    2012-06-08

    As the Sun moves through the local interstellar medium, its supersonic, ionized solar wind carves out a cavity called the heliosphere. Recent observations from the Interstellar Boundary Explorer (IBEX) spacecraft show that the relative motion of the Sun with respect to the interstellar medium is slower and in a somewhat different direction than previously thought. Here, we provide combined consensus values for this velocity vector and show that they have important implications for the global interstellar interaction. In particular, the velocity is almost certainly slower than the fast magnetosonic speed, with no bow shock forming ahead of the heliosphere, as was widely expected in the past.

  13. Bayesian Integrated Microbial Forensics

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

    Jarman, Kristin H.; Kreuzer-Martin, Helen W.; Wunschel, David S.

    2008-06-01

    In the aftermath of the 2001 anthrax letters, researchers have been exploring ways to predict the production environment of unknown source microorganisms. Different mass spectral techniques are being developed to characterize components of a microbe’s culture medium including water, carbon and nitrogen sources, metal ions added, and the presence of agar. Individually, each technique has the potential to identify one or two ingredients in a culture medium recipe. However, by integrating data from multiple mass spectral techniques, a more complete characterization is possible. We present a Bayesian statistical approach to integrated microbial forensics and illustrate its application on spores grownmore » in different culture media.« less

  14. Computational model for simulation of sequences of helicity and angular momentum transfer in turbid tissue-like scattering medium (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Doronin, Alexander; Meglinski, Igor

    2017-02-01

    Current report considers development of a unified Monte Carlo (MC) -based computational model for simulation of propagation of Laguerre-Gaussian (LG) beams in turbid tissue-like scattering medium. With a primary goal to proof the concept of using complex light for tissue diagnosis we explore propagation of LG beams in comparison with Gaussian beams for both linear and circular polarization. MC simulations of radially and azimuthally polarized LG beams in turbid media have been performed, classic phenomena such as preservation of the orbital angular momentum, optical memory and helicity flip are observed, detailed comparison is presented and discussed.

  15. Observations of interstellar zinc

    NASA Technical Reports Server (NTRS)

    Jura, M.; York, D.

    1981-01-01

    The International Ultraviolet Explorer observations of interstellar zinc toward 10 stars are examined. It is found that zinc is at most only slightly depleted in the interstellar medium; its abundance may serve as a tracer of the true metallicity in the gas. The local interstellar medium has abundances that apparently are homogeneous to within a factor of two, when integrated over paths of about 500 pc, and this result is important for understanding the history of nucleosynthesis in the solar neighborhood. The intrinsic errors in detecting weak interstellar lines are analyzed and suggestions are made as to how this error limit may be lowered to 5 mA per target observation.

  16. Blackbody emission from light interacting with an effective moving dispersive medium.

    PubMed

    Petev, M; Westerberg, N; Moss, D; Rubino, E; Rimoldi, C; Cacciatori, S L; Belgiorno, F; Faccio, D

    2013-07-26

    Intense laser pulses excite a nonlinear polarization response that may create an effective flowing medium and, under appropriate conditions, a blocking horizon for light. Here, we analyze in detail the interaction of light with such laser-induced flowing media, fully accounting for the medium dispersion properties. An analytical model based on a first Born approximation is found to be in excellent agreement with numerical simulations based on Maxwell's equations and shows that when a blocking horizon is formed, the stimulated medium scatters light with a blackbody emission spectrum. Based on these results, diamond is proposed as a promising candidate medium for future studies of Hawking emission from artificial, dispersive horizons.

  17. Mechanisms of the post-antibiotic effects induced by rifampicin and gentamicin in Escherichia coli.

    PubMed

    Stubbings, William; Bostock, Julieanne; Ingham, Eileen; Chopra, Ian

    2006-08-01

    The mechanisms by which antibiotics induce a post-antibiotic effect in susceptible bacteria are poorly understood. To explore the mechanisms more fully we examined the recovery of macromolecular synthesis in Escherichia coli during gentamicin- and rifampicin-induced post-antibiotic effects. E. coli ATCC 25922 was exposed to rifampicin and to gentamicin at 5x MIC for 60 min to induce post-antibiotic effects. The antibiotics were then removed from the culture medium by washing the cells. The rates of DNA, RNA and protein synthesis during the post-antibiotic effect and recovery periods were subsequently determined by measuring the incorporation of radiolabelled uridine, thymidine and leucine into trichloroacetic acid precipitable material. Recovery of E. coli ATCC 25922 from the rifampicin-induced post-antibiotic effect coincided with the recovery of RNA and protein synthesis. Recovery from the gentamicin-induced post-antibiotic effect coincided with the recovery of protein synthesis. These data support the hypothesis that antibiotic molecules retained in the cell mediate the post-antibiotic effect by suppressing the biochemical activity of their molecular targets.

  18. Increased efficiency of mammalian somatic cell hybrid production under microgravity conditions during ballistic rocket flight

    NASA Technical Reports Server (NTRS)

    Schnettler, R.; Gessner, P.; Zimmermann, U.; Neil, G. A.; Urnovitz, H. B.

    1989-01-01

    The electrofusion of hybridoma cell lines under short-duration microgravity during a flight of the TEXUS 18 Black Brand ballistic sounding rocket at Kiruna, Sweden is reported. The fusion partners, growth medium, cell fusion medium, cell fusion, cell viability in the fusion medium, and postfusion cell culture are described, and the rocket, cell fusion chamber, apparatus, and module are examined. The experimental timeline, the effects of fusion medium and incubation time on cell viability and hybrid yields, and the effect of microgravity on hybrid yields are considered.

  19. Protease production by fermentation of fish solubles from salmon canning processes.

    PubMed

    Wah-On, H C; Branion, R M; Strasdine, G A

    1980-09-01

    Production of protease by fermentation, using Sorangium 495, of a substrate based on condensed fish solubles is demonstrated. The effects of carbohydrate addition, pH, fish solubles concentration, scale-up, agitation, and air flow rate on protease yields are described. While the fish solubles medium alone could give rise to measurable yields of protease, these were, at worst, doubled when 1% glucose was added to the medium. pH 7 was optimal for protease yield. Although the concentration of fish solubles in the basic medium showed no significant effect on cell yield, maximum protease yield was observed at a protein concentration equivalent to 3.85 mg/mL of bovine serum albumin. Protease production rates decreased as medium protein fermentor showed no significant effect on maximum protease yields. The effects of agitator speed and air flow rate on protease yield suggested that the rate of O2 transfer from air to medium could limit the rate of protease production. It was also noted that protease production is not growth associated.

  20. Remote sensing of Earth terrain

    NASA Technical Reports Server (NTRS)

    Kong, Jin AU; Yueh, Herng-Aung

    1990-01-01

    The layered random medium model is used to investigate the fully polarimetric scattering of electromagnetic waves from vegetation. The vegetation canopy is modeled as an anisotropic random medium containing nonspherical scatterers with preferred alignment. The underlying medium is considered as a homogeneous half space. The scattering effect of the vegetation canopy are characterized by 3-D correlation functions with variances and correlation lengths respectively corresponding to the fluctuation strengths and the physical geometries of the scatterers. The strong fluctuation theory is used to calculate the anisotropic effective permittivity tensor of the random medium and the distorted Born approximation is then applied to obtain the covariance matrix which describes the fully polarimetric scattering properties of the vegetation field. This model accounts for all the interaction processes between the boundaries and the scatterers and includes all the coherent effects due to wave propagation in different directions such as the constructive and destructive interferences. For a vegetation canopy with low attenuation, the boundary between the vegetation and the underlying medium can give rise to significant coherent effects.

  1. How Does the Medium Affect the Message?

    ERIC Educational Resources Information Center

    Dommermuth, William P.

    1974-01-01

    This experimental comparison of the advertising effectiveness of television, movies, radio, and print finds no support for McLuhan's idea that television is a "cool" medium and movies are a "hot" medium. (RB)

  2. University Academic Excellence and Language Policy: A Case of Russia

    ERIC Educational Resources Information Center

    Atabekova, Anastasia A.; Gorbatenko, Rimma G.; Shoustikova, Tatyana V.

    2016-01-01

    The paper focuses on the university academic excellence projects worldwide and tries to explore the higher education institutions experience and trends regarding their language policies within the international landscape and increasing globalisation. The article agrees that English goes as a major medium of instruction at universities that strive…

  3. Sticky to Dry; Red to Purple: Exploring Transformation with Play Dough.

    ERIC Educational Resources Information Center

    Goldhaber, Jeanne

    1992-01-01

    Play dough is the perfect medium for creating, observing, and thinking about change. Whether the use of play dough is seen as play or a demonstration of physics, through its use children learn about transformations of consistency, color, and identity; and teachers observe how young children learn. (LB)

  4. Students' Silence and Identity in Small Group Interactions

    ERIC Educational Resources Information Center

    Jin, Jun

    2017-01-01

    Problem-based learning (PBL) has been increasingly employed as a teaching and learning approach in many disciplines in higher education. In English medium of instruction (EMI) universities in Asia, PBL can further enhance knowledge construction as well as development of disciplinary language and communicative skills. It is necessary to explore how…

  5. Bottle Caps as Prekindergarten Mathematical Tools

    ERIC Educational Resources Information Center

    Raisor, Jill M.; Hudson, Rick A.

    2018-01-01

    Early childhood provides a time of crucial growth in all developmental domains. Prekindergarten is an optimal time for young children to use objects of play as a medium to explore new cognitive concepts, including mathematical structure. Mathematical structure plays an important role in providing students a means to reason about mathematics,…

  6. Performing Leadership: Use of Performative Inquiry in Teaching Organizational Theories

    ERIC Educational Resources Information Center

    Nilson, Michelle; Fels, Lynn; Gopaul, Bryan

    2016-01-01

    This research explores the various ways in which performative inquiry was implemented in a graduate organizational theories course within an educational leadership cohort at a medium-sized urban Canadian research university. Drawing on Fink's framework for significant learning experiences, the researchers used performative inquiry to enact the…

  7. Fostering Critical Thinking through Interdisciplinary Cooperation: Integrating Secondary Level Physics into a Weight Training Unit.

    ERIC Educational Resources Information Center

    Downing, John H.; Lander, Jeffrey E.

    1997-01-01

    Integrating physical training with physics concepts gives teachers increased opportunities for exploration, problem solving, and concept application, while providing an additional medium for cooperative learning and mutual understanding of each others' goals and objectives. An interdisciplinary model requires alternative planning and preparation…

  8. Developing children and multicultural attitudes: the systemic psychosocial influences of television portrayals in a multimedia society.

    PubMed

    Berry, Gordon L

    2003-11-01

    Television can be an important medium for the teaching and learning of the developing child. This article explores how social learning theory and the cross-cultural images and portrayals on television might influence the multicultural attitudes, values, and beliefs of children.

  9. Poetic Machines: From Paper to Pixel

    ERIC Educational Resources Information Center

    Naji, Jeneen

    2013-01-01

    This chapter investigates digital methods of signification in order to examine the impact of the digital medium on poetic expression. Traditional poetry criticism is problematised with reference to its suitability for application to online works in order to develop a comprehensive ePoetry rhetoric that explores not only what is being said, but…

  10. Adolescents' Drawings: A View of Their Worlds.

    ERIC Educational Resources Information Center

    Chula, Marleyne

    This qualitative study investigated the medium of drawings as a methodological technique for visual data analysis. The study explored graphical symbols as an additional source for descriptive, interpretive inquiry. The design focused on gaining insight into the perceptions of adolescents' experiences as expressed by the visual narratives in their…

  11. Experiential Learning in Accounting Work-Integrated Learning: A Three-Way Partnership

    ERIC Educational Resources Information Center

    Elijido-Ten, Evangeline; Kloot, Louise

    2015-01-01

    Purpose: Work-integrated learning (WIL) helps improve the work readiness of accounting graduates. The purpose of this paper is to explore the role played by large and small-to-medium enterprise (SME) employers in providing experiential learning opportunities to accounting students in an Australian higher education context.…

  12. Digital Games as Multirepresentational Environments for Science Learning: Implications for Theory, Research, and Design

    ERIC Educational Resources Information Center

    Virk, Satyugjit; Clark, Douglas; Sengupta, Pratim

    2015-01-01

    Environments in which learning involves coordinating multiple external representations (MERs) can productively support learners in making sense of complex models and relationships. Educational digital games provide an increasing popular medium for engaging students in manipulating and exploring such models and relationships. This article applies…

  13. The Stabilization, Exploration, and Expression of Computer Game History

    ERIC Educational Resources Information Center

    Kaltman, Eric

    2017-01-01

    Computer games are now a significant cultural phenomenon, and a significant artistic output of humanity. However, little effort and attention have been paid to how the medium of games and interactive software developed, and even less to the historical storage of software development documentation. This thesis borrows methodologies and practices…

  14. Learning about Learning: Action Learning in Times of Organisational Change

    ERIC Educational Resources Information Center

    Hill, Robyn

    2009-01-01

    This paper explores the conduct and outcomes of an action learning activity during a period of intense organisational change in a medium-sized vocational education and training organisation in Victoria, Australia. This organisation was the subject of significant change due to government-driven and statewide amalgamation, downsizing and sector…

  15. Dissolved oxygen concentration in the medium during cell culture: Defects and improvements.

    PubMed

    Zhang, Kuan; Zhao, Tong; Huang, Xin; He, Yunlin; Zhou, Yanzhao; Wu, Liying; Wu, Kuiwu; Fan, Ming; Zhu, Lingling

    2016-03-01

    In vitro cell culture has provided a useful model to study the effects of oxygen on cellular behavior. However, it remains unknown whether the in vitro operations themselves affect the medium oxygen levels and the living states of cells. In addition, a prevailing controversy is whether reactive oxygen species (ROS) production is induced by continuous hypoxia or reoxygenation. In this study, we have measured the effects of different types of cell culture containers and the oxygen environment where medium replacement takes place on the actual oxygen tension in the medium. We found that the deviations of oxygen concentrations in the medium are much greater in 25-cm(2) flasks than in 24-well plates and 35-mm dishes. The dissolved oxygen concentrations in the medium were increased after medium replacement in normoxia, but remained unchanged in glove boxes in which the oxygen tension remained at a low level (11.4, 5.7, and 0.5% O2 ). We also found that medium replacement in normoxia increased the number of ROS-positive cells and reduced the cell viability; meanwhile, medium replacement in a glove box did not produce the above effects. Therefore, we conclude that the use of 25-cm(2) flasks should be avoided and demonstrate that continuous hypoxia does not produce ROS, whereas the reoxygenation that occurs during the harvesting of cells leads to ROS and induces cell death. © 2015 International Federation for Cell Biology.

  16. Optical characterization of randomly microrough surfaces covered with very thin overlayers using effective medium approximation and Rayleigh-Rice theory

    NASA Astrophysics Data System (ADS)

    Ohlídal, Ivan; Vohánka, Jiří; Čermák, Martin; Franta, Daniel

    2017-10-01

    The modification of the effective medium approximation for randomly microrough surfaces covered by very thin overlayers based on inhomogeneous fictitious layers is formulated. The numerical analysis of this modification is performed using simulated ellipsometric data calculated using the Rayleigh-Rice theory. The system used to perform this numerical analysis consists of a randomly microrough silicon single crystal surface covered with a SiO2 overlayer. A comparison to the effective medium approximation based on homogeneous fictitious layers is carried out within this numerical analysis. For ellipsometry of the system mentioned above the possibilities and limitations of both the effective medium approximation approaches are discussed. The results obtained by means of the numerical analysis are confirmed by the ellipsometric characterization of two randomly microrough silicon single crystal substrates covered with native oxide overlayers. It is shown that the effective medium approximation approaches for this system exhibit strong deficiencies compared to the Rayleigh-Rice theory. The practical consequences implied by these results are presented. The results concerning the random microroughness are verified by means of measurements performed using atomic force microscopy.

  17. Effect of nitrogen source concentration on curdlan production by Agrobacterium sp. ATCC 31749 grown on prairie cordgrass hydrolysates.

    PubMed

    West, Thomas P

    2016-01-01

    The effect of nitrogen source concentration on the production of the polysaccharide curdlan by the bacterium Agrobacterium sp. ATCC 31749 from hydrolysates of prairie cordgrass was examined. The highest curdlan concentrations were produced by ATCC 31749 when grown on a medium containing a solids-only hydrolysate and the nitrogen source ammonium phosphate (2.2 mM) or on a medium containing a complete hydrolysate and 3.3 mM ammonium phosphate. The latter medium sustained a higher level of bacterial curdlan production than the former medium after 144 hr. Biomass production by ATCC 31749 was highest after 144 hr when grown on a medium containing a solids-only hydrolysate and 2.2 or 8.7 mM ammonium phosphate. On the medium containing the complete hydrolysate, biomass production by ATCC 31749 was highest after 144 hr when 3.3 mM ammonium phosphate was present. Bacterial biomass production after 144 hr was greater on the complete hydrolysate medium compared to the solids-only hydrolysate medium. Curdlan yield produced by ATCC 31749 after 144 hr from the complete hydrolysate medium containing 3.3 mM ammonium phosphate was higher than from the solids-only hydrolysate medium containing 2.2 mM ammonium phosphate.

  18. Digital Games, Design, and Learning: A Systematic Review and Meta-Analysis.

    PubMed

    Clark, Douglas B; Tanner-Smith, Emily E; Killingsworth, Stephen S

    2016-03-01

    In this meta-analysis, we systematically reviewed research on digital games and learning for K-16 students. We synthesized comparisons of game versus nongame conditions (i.e., media comparisons) and comparisons of augmented games versus standard game designs (i.e., value-added comparisons). We used random-effects meta-regression models with robust variance estimates to summarize overall effects and explore potential moderator effects. Results from media comparisons indicated that digital games significantly enhanced student learning relative to nongame conditions ([Formula: see text] = 0.33, 95% confidence interval [0.19, 0.48], k = 57, n = 209). Results from value-added comparisons indicated significant learning benefits associated with augmented game designs ([Formula: see text] = 0.34, 95% confidence interval [0.17, 0.51], k = 20, n = 40). Moderator analyses demonstrated that effects varied across various game mechanics characteristics, visual and narrative characteristics, and research quality characteristics. Taken together, the results highlight the affordances of games for learning as well as the key role of design beyond medium.

  19. Digital Games, Design, and Learning

    PubMed Central

    Clark, Douglas B.; Tanner-Smith, Emily E.; Killingsworth, Stephen S.

    2016-01-01

    In this meta-analysis, we systematically reviewed research on digital games and learning for K–16 students. We synthesized comparisons of game versus nongame conditions (i.e., media comparisons) and comparisons of augmented games versus standard game designs (i.e., value-added comparisons). We used random-effects meta-regression models with robust variance estimates to summarize overall effects and explore potential moderator effects. Results from media comparisons indicated that digital games significantly enhanced student learning relative to nongame conditions (g¯ = 0.33, 95% confidence interval [0.19, 0.48], k = 57, n = 209). Results from value-added comparisons indicated significant learning benefits associated with augmented game designs (g¯ = 0.34, 95% confidence interval [0.17, 0.51], k = 20, n = 40). Moderator analyses demonstrated that effects varied across various game mechanics characteristics, visual and narrative characteristics, and research quality characteristics. Taken together, the results highlight the affordances of games for learning as well as the key role of design beyond medium. PMID:26937054

  20. A meta-analytic review of the relationship between family accommodation and OCD symptom severity.

    PubMed

    Strauss, Clara; Hale, Lucy; Stobie, Blake

    2015-06-01

    Accommodation of obsessive compulsive disorder (OCD) symptoms by family members is common. This paper presents a systematic meta-analytic review on family accommodation and OCD symptom severity. Fourteen studies investigating the relationship between family accommodation and OCD symptoms were selected. The medium effect size of the relationship between family accommodation and OCD symptom severity was significant (r = .35; 95% CI: .23 to .47), based on a Hunter-Schmidt random effects model with a total of 849 participants. Although there was some evidence of publication bias, Rosenthal's fail-safe N suggested that 596 studies with zero effect would be needed to reduce the mean effect size to non-significant. Findings are discussed in the context of the limitations of the studies, and in particular the reliance on cross-sectional designs which impede causal conclusions. Future research to evaluate a family accommodation intervention in a randomized controlled design and using mediation analysis to explore change mechanisms is called for. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Evaluating the Impact of Road Grade on Simulated Commercial Vehicle Fuel Economy Using Real-World Drive Cycles

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

    Lopp, Sean; Wood, Eric; Duran, Adam

    Commercial vehicle fuel economy is known to vary significantly with both positive and negative road grade. Medium- and heavy-duty vehicles operating at highway speeds require incrementally larger amounts of energy to pull heavy payloads up inclines as road grade increases. Non-hybrid vehicles are then unable to recapture energy on descent and lose energy through friction braking. While the on-road effects of road grade are well understood, the majority of standard commercial vehicle drive cycles feature no climb or descent requirements. Additionally, existing literature offers a limited number of sources that attempt to estimate the on-road energy implications of road grademore » in the medium- and heavy-duty space. This study uses real-world commercial vehicle drive cycles from the National Renewable Energy Laboratory's Fleet DNA database to simulate the effects of road grade on fuel economy across a range of vocations, operating conditions, and locations. Drive-cycles are matched with vocation-specific vehicle models and simulated with and without grade. Fuel use due to grade is presented, and variation in fuel consumption due to drive cycle and vehicle characteristics is explored through graphical and statistical comparison. The results of this study suggest that road grade accounts for 1%-9% of fuel use in commercial vehicles on average and up to 40% on select routes.« less

  2. Tailoring Mechanically Robust Poly(m-phenylene isophthalamide) Nanofiber/nets for Ultrathin High-Efficiency Air Filter

    PubMed Central

    Zhang, Shichao; Liu, Hui; Yin, Xia; Li, Zhaoling; Yu, Jianyong; Ding, Bin

    2017-01-01

    Effective promotion of air filtration applications proposed for fibers requires their real nanoscale diameter, optimized pore structure, and high service strength; however, creating such filter medium has proved to be a tremendous challenge. This study first establishes a strategy to design and fabricate novel poly(m-phenylene isophthalamide) nanofiber/nets (PMIA NF/N) air filter via electrospinning/netting. Our strategy results in generation of a bimodal structure including a scaffold of nanofibers and abundant two-dimensional ultrathin (~20 nm) nanonets to synchronously construct PMIA filters by combining solution optimization, humidity regulation, and additive inspiration. Benefiting from the structural features including the true nanoscale diameter, small pore size, high porosity, and nets bonding contributed by the widely distributed nanonets, our PMIA NF/N filter exhibits the integrated properties of superlight weight (0.365 g m−2), ultrathin thickness (~0.5 μm), and high tensile strength (72.8 MPa) for effective air filtration, achieving the ultra-low penetration air filter level of 99.999% and low pressure drop of 92 Pa for 300–500 nm particles by sieving mechanism. The successful synthesis of PMIA NF/N would not only provide a promising medium for particle filtration, but also develop a versatile platform for exploring the application of nanonets in structural enhancement, separation and purification. PMID:28074880

  3. UPLC-DAD/Q-TOF-MS Based Ingredients Identification and Vasorelaxant Effect of Ethanol Extract of Jasmine Flower

    PubMed Central

    Yin, Yongqiang; Ying, Xuhui; Luan, Hairong; Zhao, Zhenying; Lou, Jianshi; Wang, Deli; Li, Hailin; Wu, Hong

    2014-01-01

    Chinese people commonly make jasmine tea for recreation and health care. Actually, its medicinal value needs more exploration. In this study, vasorelaxant effect of ethanol extract of jasmine flower (EEJ) on isolated rat thoracic aorta rings was investigated and [Ca2+] was determined in vascular smooth muscle cells by laser scanning confocal microscope (LSCM). The result of aorta rings showed that EEJ could cause concentration-dependent relaxation of endothelium-intact rings precontracted with phenylephrine or KCl which was attenuated after preincubation of the rings with L-NAME and three different K+ channel inhibitors; however, indomethacin and glibenclamide did not affect the vasodilatation of EEJ. In addition, EEJ could inhibit contraction induced by PE on endothelium-denuded rings in Ca2+-free medium as well as by accumulation of Ca2+ in Ca2+-free medium with high K+. LSCM also showed that EEJ could lower the elevated level of [Ca2+] induced by KCl. These indicate that the vasodilation of EEJ is in part related to causing the release of nitric oxide, activation of K+ channels, inhibition of influx of excalcium, and release of calcium from sarcoplasmic reticulum. A total of 20 main ingredients, were identified in EEJ by UPLC-DAD/Q-TOF-MS. The vasodilation activity should be attributed to the high content of flavonoid glycosides and iridoid glycosides found in EEJ. PMID:25628748

  4. Effects of Shield1 on the viral replication of varicella-zoster virus containing FKBP-tagged ORF4 and 48

    PubMed Central

    Li, Shuying; Liu, Zhanjun; Li, Ji; Liu, Aihua; Zhu, Lihua; Yu, Kui; Zhang, Ke

    2018-01-01

    The present study aimed to explore the effects of a stabilizing ligand, Shield-1, on the replication of recombinant varicella-zoster virus (VZV) containing FK506 binding protein (FKPB) tags in essential open reading frames (ORF) 4 and 48. A specific galactokinase (galK) selection method was conducted, following the addition of galK labels to VZV ORF4 and 48, using a SW102 VZV bacterial artificial chromosome (BAC) system. Subsequently, recombinant VZV containing FKPB tags in ORF4 and 48 was constructed by counterselection and homologous recombination. Recombinant viral plasmids containing FKPB-tagged VZV ORF4 and 48 were extracted and transfected into human acute retinal pigment epithelial ARPE-19 cells. The results demonstrated that the FKPB-tagged viral protein was rapidly degraded by proteases in recombinant virus-infected ARPE-19 cells. In addition, the recombinant VZVORF4-FKBP-ORF48-FKBP virus could not grow if a synthetic ligand of FKBP, Shield1, was not added to the ARPE-19 cell culture medium; however, the degradation of FKPB-tagged viral protein was prevented if Shield1 was added to the ARPE-19 cell culture medium, thereby allowing viral replication in ARPE-19 cells. These results indicated that Shield1 may regulate replication of recombinant VZVORF4-FKBP-ORF48-FKBP following transfection into human epithelial cells. PMID:29115621

  5. Combinatorial stresses kill pathogenic Candida species

    PubMed Central

    Kaloriti, Despoina; Tillmann, Anna; Cook, Emily; Jacobsen, Mette; You, Tao; Lenardon, Megan; Ames, Lauren; Barahona, Mauricio; Chandrasekaran, Komelapriya; Coghill, George; Goodman, Daniel; Gow, Neil A. R.; Grebogi, Celso; Ho, Hsueh-Lui; Ingram, Piers; McDonagh, Andrew; De Moura, Alessandro P. S.; Pang, Wei; Puttnam, Melanie; Radmaneshfar, Elahe; Romano, Maria Carmen; Silk, Daniel; Stark, Jaroslav; Stumpf, Michael; Thiel, Marco; Thorne, Thomas; Usher, Jane; Yin, Zhikang; Haynes, Ken; Brown, Alistair J. P.

    2012-01-01

    Pathogenic microbes exist in dynamic niches and have evolved robust adaptive responses to promote survival in their hosts. The major fungal pathogens of humans, Candida albicans and Candida glabrata, are exposed to a range of environmental stresses in their hosts including osmotic, oxidative and nitrosative stresses. Significant efforts have been devoted to the characterization of the adaptive responses to each of these stresses. In the wild, cells are frequently exposed simultaneously to combinations of these stresses and yet the effects of such combinatorial stresses have not been explored. We have developed a common experimental platform to facilitate the comparison of combinatorial stress responses in C. glabrata and C. albicans. This platform is based on the growth of cells in buffered rich medium at 30°C, and was used to define relatively low, medium and high doses of osmotic (NaCl), oxidative (H 2O2) and nitrosative stresses (e.g., dipropylenetriamine (DPTA)-NONOate). The effects of combinatorial stresses were compared with the corresponding individual stresses under these growth conditions. We show for the first time that certain combinations of combinatorial stress are especially potent in terms of their ability to kill C. albicans and C. glabrata and/or inhibit their growth. This was the case for combinations of osmotic plus oxidative stress and for oxidative plus nitrosative stress. We predict that combinatorial stresses may be highly signif cant in host defences against these pathogenic yeasts. PMID:22463109

  6. Tailoring Mechanically Robust Poly(m-phenylene isophthalamide) Nanofiber/nets for Ultrathin High-Efficiency Air Filter

    NASA Astrophysics Data System (ADS)

    Zhang, Shichao; Liu, Hui; Yin, Xia; Li, Zhaoling; Yu, Jianyong; Ding, Bin

    2017-01-01

    Effective promotion of air filtration applications proposed for fibers requires their real nanoscale diameter, optimized pore structure, and high service strength; however, creating such filter medium has proved to be a tremendous challenge. This study first establishes a strategy to design and fabricate novel poly(m-phenylene isophthalamide) nanofiber/nets (PMIA NF/N) air filter via electrospinning/netting. Our strategy results in generation of a bimodal structure including a scaffold of nanofibers and abundant two-dimensional ultrathin (~20 nm) nanonets to synchronously construct PMIA filters by combining solution optimization, humidity regulation, and additive inspiration. Benefiting from the structural features including the true nanoscale diameter, small pore size, high porosity, and nets bonding contributed by the widely distributed nanonets, our PMIA NF/N filter exhibits the integrated properties of superlight weight (0.365 g m-2), ultrathin thickness (~0.5 μm), and high tensile strength (72.8 MPa) for effective air filtration, achieving the ultra-low penetration air filter level of 99.999% and low pressure drop of 92 Pa for 300-500 nm particles by sieving mechanism. The successful synthesis of PMIA NF/N would not only provide a promising medium for particle filtration, but also develop a versatile platform for exploring the application of nanonets in structural enhancement, separation and purification.

  7. Children and adolescents' performance on a medium-length/nonsemantic word-list test.

    PubMed

    Flores-Lázaro, Julio César; Salgado Soruco, María Alejandra; Stepanov, Igor I

    2017-01-01

    Word-list learning tasks are among the most important and frequently used tests for declarative memory evaluation. For example, the California Verbal Learning Test-Children's Version (CVLT-C) and Rey Auditory Verbal Learning Test provide important information about different cognitive-neuropsychological processes. However, the impact of test length (i.e., number of words) and semantic organization (i.e., type of words) on children's and adolescents' memory performance remains to be clarified, especially during this developmental stage. To explore whether a medium-length non-semantically organized test can produce the typical curvilinear performance that semantically organized tests produce, reflecting executive control, we studied and compared the cognitive performance of normal children and adolescents by utilizing mathematical modeling. The model is based on the first-order system transfer function and has been successfully applied to learning curves for the CVLT-C (15 words, semantically organized paradigm). Results indicate that learning nine semantically unrelated words produces typical curvilinear (executive function) performance in children and younger adolescents and that performance could be effectively analyzed with the mathematical model. This indicates that the exponential increase (curvilinear performance) of correctly learned words does not solely depend on semantic and/or length features. This type of test controls semantic and length effects and may represent complementary tools for executive function evaluation in clinical populations in which semantic and/or length processing are affected.

  8. Differential force balances during levitation

    NASA Astrophysics Data System (ADS)

    Todd, Paul

    The simplest arithmetic of inertial, buoyant, magnetic and electrokinetic levitation is explored in the context of a model living system with “acceleration-sensitive structures” in which motion, if allowed, produces a biological effect. The simple model is a finite-sized object enclosed within another finite-sized object suspended in an outer fluid (liquid or vapor) medium. The inner object has density and electrical and magnetic properties quantitatively different from those of the outer object and the medium. In inertial levitation (“weightlessness”) inertial accelerations are balanced, and the forces due to them are canceled in accordance with Newton’s third law. In the presence of inertial acceleration (gravity, centrifugal) motionlessness depends on a balance between the levitating force and the inertial force. If the inner and outer objects differ in density one or the other will be subjected to an unbalanced force when one object is levitated by any other force (buoyant, magnetic, electrokinetic). The requirements for motionlessness of the internal object in the presence of a levitating force are equality of density in the case of buoyant levitation, equality of magnetic susceptibility in the case of magnetic levitation, and equality of zeta potential and dielectric constant in the case of electrokinetic levitation. Examples of internal “acceleration-sensitive structures” are cellular organelles and the organs of advanced plants and animals. For these structures fundamental physical data are important in the interpretation of the effects of forces used for levitation.

  9. Cost-effective medium for the production of mosquito pupicidal lipopeptide from Bacillus subtilis subsp. subtilis (VCRC B471).

    PubMed

    Bhuvaneswari, S; Manonmani, A M; Geetha, I

    2015-03-01

    A cyclic lipopeptide (CLP), surfactin produced by a strain of Bacillus subtilis subsp. subtilis (VCRC B471) was found to exhibit mosquitocidal activity. The present study was carried out to enhance the surfactin level using low cost material in the production medium. Two carbon sources, glucose and common sugar, and two nitrogen sources, ammonium nitrate and soya were used in the study. Different concentrations of 'C' and 'N' sources were used in the production medium to enhance the production of surfactin. A new medium (SS7) containing 2% sugar, 6% soya and 0.5% common salt with micronutrients was designed which was found to enhance the production of surfactin. The crude mosquitocidal metabolite (CMM) produced in this medium was 3 g/l which was two times higher than that obtained using synthetic medium NYSM. The LC50 dosage of the CMM to the pupal stages of An. stephensi (2.3 μg/ml) was comparable to that obtained with CMM from the conventional medium. The newly designed cost-effective medium designated as sugar soya medium (SSM) enhanced the production of surfactin and the cost of production was estimated as [symbol: see text] 6 per litre, which is six times lesser than that of the conventional medium. Replacement of sodium chloride with cooking salt further reduced the cost of the medium.

  10. Method of dispensing droplets to penetration-resistive mediums. [Patent application

    DOEpatents

    Fowler, V.L.; Ryon, A.D.; Haas, P.A.

    1982-06-10

    Uniform, monosized microspheroids are produced in a gelation medium characterized by a high resistance to surface penetration by reducing the effect of impact on entry of the droplets into the medium by contacting the droplet with a stream of medium and by introducing the resulting stream into a gelation column.

  11. Effect of boric acid solution on cartilage metabolism.

    PubMed

    Benderdour, M; Hess, K; Gadet, M D; Dousset, B; Nabet, P; Belleville, F

    1997-05-08

    Pelvic cartilage of chick embryo was used to demonstrate that presence of boron in culture medium decreases synthesis of proteoglycans, collagen and total proteins but on the other hand increases the release of these macromolecules. However, when glucose concentration in culture medium is brought to 22mM, the synthesis decrease is no longer observed, whereas release increase persists. Proteins released into the culture medium included heat shock proteins (70 hsp) and tumor necrosis factor alpha (TNF alpha). The amount of phosphorylated proteins was enhanced in presence of boron while endoprotease activity in cartilage and in culture medium was significantly augmented. The in vitro effects of boric acid may explain its in vivo effect on wound healing.

  12. Viscoelastic modeling of deformation and gravity changes induced by pressurized magmatic sources

    NASA Astrophysics Data System (ADS)

    Currenti, Gilda

    2018-05-01

    Gravity and height changes, which reflect magma accumulation in subsurface chambers, are evaluated using analytical and numerical models in order to investigate their relationships and temporal evolutions. The analysis focuses mainly on the exploration of the time-dependent response of gravity and height changes to the pressurization of ellipsoidal magmatic chambers in viscoelastic media. Firstly, the validation of the numerical Finite Element results is performed by comparison with analytical solutions, which are devised for a simple spherical source embedded in a homogeneous viscoelastic half-space medium. Then, the effect of several model parameters on time-dependent height and gravity changes is investigated thanks to the flexibility of the numerical method in handling complex configurations. Both homogeneous and viscoelastic shell models reveal significantly different amplitudes in the ratio between gravity and height changes depending on geometry factors and medium rheology. The results show that these factors also influence the relaxation characteristic times of the investigated geophysical changes. Overall, these temporal patterns are compatible with time-dependent height and gravity changes observed on Etna volcano during the 1994-1997 inflation period. By modeling the viscoelastic response of a pressurized prolate magmatic source, a general agreement between computed and observed geophysical variations is achieved.

  13. Characterisation of transition state structures for protein folding using 'high', 'medium' and 'low' {Phi}-values.

    PubMed

    Geierhaas, Christian D; Salvatella, Xavier; Clarke, Jane; Vendruscolo, Michele

    2008-03-01

    It has been suggested that Phi-values, which allow structural information about transition states (TSs) for protein folding to be obtained, are most reliably interpreted when divided into three classes (high, medium and low). High Phi-values indicate almost completely folded regions in the TS, intermediate Phi-values regions with a detectable amount of structure and low Phi-values indicate mostly unstructured regions. To explore the extent to which this classification can be used to characterise in detail the structure of TSs for protein folding, we used Phi-values divided into these classes as restraints in molecular dynamics simulations. This type of procedure is related to that used in NMR spectroscopy to define the structure of native proteins from the measurement of inter-proton distances derived from nuclear Overhauser effects. We illustrate this approach by determining the TS ensembles of five proteins and by showing that the results are similar to those obtained by using as restraints the actual numerical Phi-values measured experimentally. Our results indicate that the simultaneous consideration of a set of low-resolution Phi-values can provide sufficient information for characterising the architecture of a TS for folding of a protein.

  14. Health-Related Quality of Life and Its Correlates among Chinese Migrants in Small- and Medium-Sized Enterprises in Two Cities of Guangdong

    PubMed Central

    Lu, Liming; Zou, Guanyang; Zeng, Zhi; Han, Lu; Guo, Yan; Ling, Li

    2014-01-01

    Objectives To explore the relationship between health-related quality of life (HRQOL) status and associated factors among rural-to-urban migrants in China. Methods A cross-sectional survey was conducted with 856 rural-to-urban migrants working at small- and medium-size enterprises (SMEs) in Shenzhen and Zhongshan City in 2012. Andersen's behavioral model was used as a theoretical framework to exam the relationships among factors affecting HRQOL. Analysis was performed using structural equation modeling (SEM). Results Workers with statutory working hours, higher wages and less migrant experience had higher HRQOL scores. Need (contracting a disease in the past two weeks and perception of needing health service) had the greatest total effect on HRQOL (β = −0.78), followed by enabling (labor contract, insurance purchase, income, physical examination during work and training) (β = 0.40), predisposing (age, family separation, education) (β = 0.22) and health practices and use of health service (physical exercise weekly, health check-up and use of protective equipments) (β = −0.20). Conclusions Priority should be given to satisfy the needs of migrant workers, and improve the enabling resources. PMID:24392084

  15. Clean Power Generation from the Intractable Natural Coalfield Fires: Turn Harm into Benefit.

    PubMed

    Shi, Bobo; Su, Hetao; Li, Jinshi; Qi, Haining; Zhou, Fubao; Torero, José L; Chen, Zhongwei

    2017-07-13

    The coal fires, a global catastrophe for hundreds of years, have been proved extremely difficult to control, and hit almost every coal-bearing area globally. Meanwhile, underground coal fires contain tremendous reservoir of geothermal energy. Approximately one billion tons of coal burns underground annually in the world, which could generate ~1000 GW per annum. A game-changing approach, environmentally sound thermal energy extraction from the intractable natural coalfield fires, is being developed by utilizing the waste energy and reducing the temperature of coalfield fires at the same time. Based on the Seebeck effect of thermoelectric materials, the temperature difference between the heat medium and cooling medium was employed to directly convert thermal energy into clean electrical energy. By the time of December 2016, the power generation from a single borehole at Daquan Lake fire district in Xinjiang has been exceeded 174.6 W. The field trial demonstrates that it is possible to exploit and utilize the waste heat resources in the treated coal fire areas. It promises a significant impact on the structure of global energy generation and can also promote progress in thermoelectric conversion materials, geothermal exploration, underground coal fires control and other energy related areas.

  16. A Multiphase Model for the Intracluster Medium

    NASA Technical Reports Server (NTRS)

    Nagai, Daisuke; Sulkanen, Martin E.; Evrard, August E.

    1999-01-01

    Constraints on the clustered mass density of the universe derived from the observed population mean intracluster gas fraction of x-ray clusters may be biased by reliance on a single-phase assumption for the thermodynamic structure of the intracluster medium (ICM). We propose a descriptive model for multiphase structure in which a spherically symmetric ICM contains isobaric density perturbations with a radially dependent variance. Fixing the x-ray emission and emission weighted temperature, we explore two independently observable signatures of the model in the parameter space. For bremsstrahlung dominated emission, the central Sunyaev-Zel'dovich (SZ) decrement in the multiphase case is increased over the single-phase case and multiphase x-ray spectra in the range 0.1-20 keV are flatter in the continuum and exhibit stronger low energy emission lines than their single-phase counterpart. We quantify these effects for a fiducial 10e8 K cluster and demonstrate how the combination of SZ and x-ray spectroscopy can be used to identify a preferred location in the plane of the model parameter space. From these parameters the correct value of mean intracluster gas fraction in the multiphase model results, allowing an unbiased estimate of clustered mass density to he recovered.

  17. Role of muscle spindle in weightlessness-induced amyotrophia and muscle pain.

    PubMed

    Ali, Umar; Fan, Xiao-Li; You, Hao-Jun

    2009-10-01

    To date, the medium and long-term space flight is urgent in need and has become a major task of our manned space flight program. There is no doubt that medium and long-term space flight has serious damaging impact upon human physiological systems. For instance, atrophy of the lower limb anti-gravity muscle can be induced during the space flight. Muscle atrophy significantly affects the flight of astronauts in space. Most importantly, it influences the precise manipulation of the astronauts and their response capacity to emergencies on returning to the atmosphere from space. Muscle atrophy caused by weightlessness may also seriously disrupt the normal life and work of the astronauts during the re-adaptation period. Here we summarize the corresponding research concentrating on weightlessness-induced changes of muscular structure and function. By combining research on muscle pain, which is a common clinical pain disease, we further provide a hypothesis concerning a dynamic feedback model of "weightlessness condition right triple arrow muscular atrophy <--> muscle pain". This may be useful to explore the neural mechanisms underlying the occurrence and development of muscular atrophy and muscle pain, through the key study of muscle spindle, and furthermore provide more effective therapy for clinical treatment.

  18. Striatal Infusion of Glial Conditioned Medium Diminishes Huntingtin Pathology in R6/1 Mice

    PubMed Central

    Perucho, Juan; Casarejos, Maria José; Gómez, Ana; Ruíz, Carolina; Fernández-Estevez, Maria Ángeles; Muñoz, Maria Paz; de Yébenes, Justo García; Mena, Maria Ángeles

    2013-01-01

    Huntington's disease is a neurodegenerative disorder caused by an expansion of CAG repeats in the huntingtin gene which produces widespread neuronal and glial pathology. We here investigated the possible therapeutic role of glia or glial products in Huntington's disease using striatal glial conditioned medium (GCM) from fetus mice (E16) continuously infused for 15 and 30 days with osmotic minipumps into the left striatum of R6/1 mice. Animals infused with GCM had significantly less huntingtin inclusions in the ipsilateral cerebral cortex and in the ipsilateral and contralateral striata than mice infused with cerebrospinal fluid. The numbers of DARPP-32 and TH positive neurons were also greater in the ipsilateral but not contralateral striata and substantia nigra, respectively, suggesting a neuroprotective effect of GCM on efferent striatal and nigro-striatal dopamine neurons. GCM increases activity of the autophagic pathway, as shown by the reduction of autophagic substrate, p-62, and the augmentation of LC3 II, Beclin-1 and LAMP-2 protein levels, direct markers of autophagy, in GCM infused mice. GCM also increases BDNF levels. These results suggest that CGM should be further explored as a putative neuroprotective agent in Huntington's disease. PMID:24069174

  19. Contemporary women's secure psychiatric services in the United Kingdom: A qualitative analysis of staff views.

    PubMed

    Walker, T; Edge, D; Shaw, J; Wilson, H; McNair, L; Mitchell, H; Gutridge, K; Senior, J; Sutton, M; Meacock, R; Abel, K

    2017-11-01

    WHAT IS KNOWN ON THE SUBJECT?: Three pilot UK-only Women's Enhanced Medium Secure Services (WEMSS) was opened in 2007 to support women's movement from high secure care and provide a bespoke, women-only service. Evidence suggests that women's secure services are particularly challenging environments to work in and staffing issues (e.g., high turnover) can cause difficulties in establishing a therapeutic environment. Research in this area has focused on the experiences of service users. Studies which have examined staff views have focused on their feelings towards women in their care and the emotional burden of working in women's secure services. No papers have made a direct comparison between staff working in different services. WHAT DOES THIS STUDY ADD TO EXISTING KNOWLEDGE?: This is the first study to explore the views and experiences of staff in the three UK WEMSS pilot services and contrast them with staff from women's medium secure services. Drawing upon data from eighteen semi-structured interviews (nine WEMSS, nine non-WEMSS), key themes cover staff perceptions of factors important for women's recovery and their views on operational aspects of services. This study extends our understanding of the experiences of staff working with women in secure care and bears relevance for staff working internationally, as well as in UK services. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: The study reveals the importance of induction and training for bank and agency staff working in women's secure services. Further, regular clinical supervision should be mandatory for all staff so they are adequately supported. Introduction Women's Enhanced Medium Secure Services (WEMSS) is bespoke, gender-sensitive services which opened in the UK in 2007 at three pilot sites. This study is the first of its kind to explore the experiences of WEMSS staff, directly comparing them to staff in a standard medium secure service for women. The literature to date has focused on the experiences of service users or staff views on working with women in secure care. Aim This qualitative study, embedded in a multimethod evaluation of WEMSS, aimed to explore the views and experiences of staff in WEMSS and comparator medium secure services. Methods Qualitative interviews took place with nine WEMSS staff and nine comparator medium secure staff. Interviews focused on factors important for recovery, barriers to facilitating recovery and operational aspects of the service. Discussion This study provides a rare insight into the perspectives of staff working in UK women's secure services, an under-researched area in the UK and internationally. Findings suggest that the success of services, including WEMSS, is compromised by operational factors such as the use of bank staff. Implications for practice Comprehensive training and supervision should be mandatory for all staff, so best practice is met and staff adequately supported. © 2017 John Wiley & Sons Ltd.

  20. Breast fibroblasts in both cancer and normal tissues induce phenotypic transformation of breast cancer stem cells: a preliminary study

    PubMed Central

    Xi, Chunfang; Liu, Mingwei; Sun, Haichen; Liu, Shuang; Song, Lei

    2018-01-01

    Background Breast cancer stem cells (BCSCs) are associated with the invasion of breast cancer. In recent years, studies have demonstrated different phenotypes among BCSCs. Furthermore, BCSCs of diverse phenotypes are present at different tumour sites and different histological stages. Fibroblasts are involved in the phenotypic transformation of BCSCs. Cancer-associated fibroblasts (CAFs) participate in the induction of epithelial–mesenchymal transition, thereby promoting the acquisition of stem cell characteristics, but little is known about the role of normal fibroblasts (NFs) in the phenotypic transformation of BCSCs or about the effect of CAFs and NFs on BCSC phenotypes. Methods A total of six pairs of primary CAFs and NFs were isolated from surgical samples of breast cancer patients and subjected to morphological, immunohistochemical, cell invasion and proteomics analyses. After establishing a cell culture system with conditioned medium from CAFs and NFs, we used the mammosphere formation assay to explore the effect of CAFs and NFs on the self-renewal ability of BCSCs. The effect of CAFs and NFs on the phenotypic differentiation of BCSCs was further analysed by flow cytometry and immunofluorescence. Results The isolated CAFs and NFs did not show significant differences in cell morphology or alpha-smooth muscle actin (α-SMA) expression, but cell invasion and proteomics analyses demonstrated heterogeneity among these fibroblasts. Both CAFs and NFs could promote the generation of BCSCs, but CAFs displayed a greater ability than NFs in promoting mammosphere formation. Conditioned medium from CAFs increased the proportion of aldehyde dehydrogenase-1 positive (ALDH1+) BCSCs, but conditioned medium from NFs was more likely to promote the generation of CD44+CD24− BCSCs from MCF-7 cells. Discussion This study validated the heterogeneity among CAFs and NFs and expanded on the conclusion that fibroblasts promote the generation of cancer stem cells. Our results particularly emphasized the effect of NFs on the phenotypic transformation of BCSCs. In addition, this study further highlighted the roles of CAFs and NFs in the induction of different phenotypes in BCSCs. PMID:29780673

  1. Breast fibroblasts in both cancer and normal tissues induce phenotypic transformation of breast cancer stem cells: a preliminary study.

    PubMed

    Wang, Bixiao; Xi, Chunfang; Liu, Mingwei; Sun, Haichen; Liu, Shuang; Song, Lei; Kang, Hua

    2018-01-01

    Breast cancer stem cells (BCSCs) are associated with the invasion of breast cancer. In recent years, studies have demonstrated different phenotypes among BCSCs. Furthermore, BCSCs of diverse phenotypes are present at different tumour sites and different histological stages. Fibroblasts are involved in the phenotypic transformation of BCSCs. Cancer-associated fibroblasts (CAFs) participate in the induction of epithelial-mesenchymal transition, thereby promoting the acquisition of stem cell characteristics, but little is known about the role of normal fibroblasts (NFs) in the phenotypic transformation of BCSCs or about the effect of CAFs and NFs on BCSC phenotypes. A total of six pairs of primary CAFs and NFs were isolated from surgical samples of breast cancer patients and subjected to morphological, immunohistochemical, cell invasion and proteomics analyses. After establishing a cell culture system with conditioned medium from CAFs and NFs, we used the mammosphere formation assay to explore the effect of CAFs and NFs on the self-renewal ability of BCSCs. The effect of CAFs and NFs on the phenotypic differentiation of BCSCs was further analysed by flow cytometry and immunofluorescence. The isolated CAFs and NFs did not show significant differences in cell morphology or alpha-smooth muscle actin (α-SMA) expression, but cell invasion and proteomics analyses demonstrated heterogeneity among these fibroblasts. Both CAFs and NFs could promote the generation of BCSCs, but CAFs displayed a greater ability than NFs in promoting mammosphere formation. Conditioned medium from CAFs increased the proportion of aldehyde dehydrogenase-1 positive (ALDH1 + ) BCSCs, but conditioned medium from NFs was more likely to promote the generation of CD44 + CD24 - BCSCs from MCF-7 cells. This study validated the heterogeneity among CAFs and NFs and expanded on the conclusion that fibroblasts promote the generation of cancer stem cells. Our results particularly emphasized the effect of NFs on the phenotypic transformation of BCSCs. In addition, this study further highlighted the roles of CAFs and NFs in the induction of different phenotypes in BCSCs.

  2. Influence of Side Effects on ART Adherence Among PLWH in China: The Moderator Role of ART-Related Knowledge.

    PubMed

    Zhou, Guangyu; Li, Xiaoming; Qiao, Shan; Shen, Zhiyong; Zhou, Yuejiao

    2018-03-01

    Despite the medical advancements in HIV treatment, realities of side effects are faced by people living with HIV (PLWH) who receive antiretroviral therapy (ART). Mixed findings have been reported on the association between side effects and ART adherence. However, few studies have explored the combined side effects and behavior-related information on medication adherence. The aim of the current study is to examine moderator role of ART-related knowledge between side effects and ART adherence. A cross-sectional survey was conducted among 2987 PLWH from October 2012 to August 2013 in China. Of the total sample, 2095 patients had received ART and provided ART adherence. Side effects, ART-related knowledge, and ART adherence, as well as potential covariates were assessed. The results revealed that there was a negative relationship of side effects and ART adherence existed among low and medium levels of ART-related knowledge, but not among high level of knowledge. Future interventions to promote HIV medication adherence should focus on providing behavior-related information education among PLWH.

  3. Highly selective medium for isolation of Listeria monocytogenes from food.

    PubMed Central

    al-Zoreky, N; Sandine, W E

    1990-01-01

    A new selective medium (Al-Zoreky-Sandine listeria medium [ASLM]) was formulated to recover Listeria monocytogenes from food specimens; the medium completely inhibited common food microflora. Recognition of Listeria colonies is evident by black discoloration of the medium due to esculin hydrolysis without need for special illuminating equipment. The medium contains acriflavin, ceftazidime, and moxalactam as selective agents. Compared with Listeria Selective Agar, ASLM was equally effective in recovering L. monocytogenes. However, ASLM inhibited micrococci, enterococci, and gram-negative bacteria, especially a strain that mimicked L. monocytogenes on Listeria Selective Agar. The new medium was able to recover heat injured cells with only 15% less count than the nonselective medium. Images PMID:2126701

  4. Effects of phenolic constituents of daylily flowers on corticosterone- and glutamate-treated PC12 cells.

    PubMed

    Tian, Huan; Yang, Fei-Fei; Liu, Chun-Yu; Liu, Xin-Min; Pan, Rui-Le; Chang, Qi; Zhang, Ze-Sheng; Liao, Yong-Hong

    2017-01-21

    Daylily flowers, the flower and bud parts of Hemerocallis citrina or H. fulva, are well known as Wang-You-Cao in Chinese, meaning forget-one's sadness plant. However, the major types of active constituents responsible for the neurological effects remain unclear. This study was to examine the protective effects of hydroalcoholic extract and fractions and to identify the active fractions. The extract of daylily flowers was separated with AB-8 resin into different fractions containing non-phenolic compounds, phenolic acid derivatives and flavonoids as determined using UPLC-DAD chromatograms. The neuroprotective activity was measured by evaluating the cell viability and lactate dehydrogenase release using PC12 cell damage models induced by corticosterone and glutamate. The neurological mechanisms were explored by determining their effect on the levels of dopamine (DA), 5-hydroxy tryptamine (5-HT), γ-aminobutyric acid (GABA), noradrenaline (NE) and acetylcholine (ACh) in the cell culture medium measured using an LC-MS/MS method. Pretreatment of PC12 cells with the extract and phenolic fractions of daylily flowers at concentrations ranging from 0.63 to 5 mg raw material/mL significantly reversed corticosterone- and glutamate-induced neurotoxicity in a dose-dependent manner. The fractions containing phenolic acid derivatives (0.59% w/w in the flowers) and/or flavonoids (0.60% w/w) exerted similar dose-dependent neuroprotective effect whereas the fractions with non-phenolic compounds exhibited no activity. The presence of phenolic acid derivatives in the corticosterone- and glutamate-treated PC12 cells elevated the DA level in the cell culture medium whereas flavonoids resulted in increased ACH and 5-HT levels. Phenolic acid derivatives and flavonoids were likely the active constituents of daylily flowers and they conferred a similar extent of neuroprotection, but affected the release of neurotransmitters in a different manner.

  5. Cost-effectiveness of annual targeted larviciding campaigns in Cambodia against the dengue vector Aedes aegypti.

    PubMed

    Suaya, Jose A; Shepard, Donald S; Chang, Moh-Seng; Caram, Mariana; Hoyer, Stefan; Socheat, Duong; Chantha, Ngan; Nathan, Michael B

    2007-09-01

    To assess the cost-effectiveness (CE) of annual targeted larviciding campaigns from 2001 to 2005 against the dengue vector Aedes aegypti in two urban areas of Cambodia with a population of 2.9 million people. The intervention under analysis consisted of annual larviciding campaigns targeting medium to large water storage containers in households and other premises. The CE compared the intervention against the hypothetical alternative of no intervention. The CE was calculated as the ratio of disability adjusted life years (DALYs) saved to the net cost of the intervention (in 2005 US dollars) by year. A sensitivity analysis explored the range of study parameters. The intervention reduced the number of dengue cases and deaths by 53%. It averted an annual average of 2980 dengue hospitalizations, 11,921 dengue ambulatory cases and 23 dengue deaths, resulting in a saving of 997 DALYs per year. The gross cost of the intervention was US $567,800 per year, or US $0.20 per person covered. As the intervention averted considerable medical care, the annual net cost of the intervention was US $312,214 (US $0.11 per person covered) from a public sector perspective and US $37,137 (US $0.01 per person covered) from a societal perspective. The resulting CE ratios were: US $313/DALY gained from the public perspective and US $37/DALY gained from the societal perspective. Even under the most conservative assumption, the intervention remained cost effective from both perspectives. Annual, targeted larviciding campaigns appear to have been effective and cost-effective medium-term interventions to reduce the epidemiologic and economic burden of dengue in urban areas of Cambodia.

  6. Ethanol production using a soy hydrolysate-based medium or a yeast autolysate-based medium

    DOEpatents

    Ingram, Lonnie O.

    2000-01-01

    This invention presents a method for the production of ethanol that utilizes a soy hydrolysate-based nutrient medium or a yeast autolysate-based medium nutrient medium in conjunction with ethanologenic bacteria and a fermentable sugar for the cost-effective production of ethanol from lignocellulosic biomass. The invention offers several advantages over presently available media for use in ethanol production, including consistent quality, lack of toxins and wide availability.

  7. Paradoxical monocular stereopsis and perspective vergence

    NASA Technical Reports Server (NTRS)

    Enright, J. T.

    1989-01-01

    The question of how to most effectively convey depth in a picture is a multifaceted problem, both because of potential limitations of the chosen medium (stereopsis, image motion), and because effectiveness can be defined in various ways. Practical applications usually focus on information transfer, i.e., effective techniques for evoking recognition of implied depth relationships, but this issue depends on subjective judgements which are difficult to scale when stimuli are above threshold. Two new approaches to this question are proposed here which are based on alternative criteria for effectiveness. Paradoxical monocular stereopsis is a remarkably compelling impression of depth which is evoked during one-eyed viewing of only certain illustrations; it can be unequivocally recognized because the feeling of depth collapses when one shifts to binocular viewing. An exploration of the stimulus properties which are effective for this phenomenon may contribute useful answers for the more general perceptual problem. Positive vergence is an eye-movement response associated with changes of fixation point within a picture which implies depth; it also arises only during monocular viewing. The response is directionally appropriate (i.e., apparently nearer objects evoke convergence, and vice versa), but the magnitude of the response can be altered consistently by making relatively minor changes in the illustration. The cross-subject agreement in changes of response magnitude would permit systematic exploration to determine which stimulus configurations are most effective in evoking perspective vergence, with quantitative answers based upon this involuntary reflex. It may well be that most effective pictures in this context will embody features which would increase effectiveness of pictures in a more general sense.

  8. An extended car-following model with consideration of vehicle to vehicle communication of two conflicting streams

    NASA Astrophysics Data System (ADS)

    Zhao, Jing; Li, Peng

    2017-05-01

    In this paper, we propose a car-following model to explore the influences of V2V communication on the driving behavior at un-signalized intersections with two crossing streams and to explore how the speed guidance strategy affects the operation efficiency. The numerical results illustrate that the benefits of the guidance strategy could be enhanced by lengthening the guiding space range and increasing the maximum speed limitation, and that the guidance strategy is more suitable under low to medium traffic density and small safety interval condition.

  9. The Extreme Ultraviolet Explorer mission - Overview and initial results

    NASA Technical Reports Server (NTRS)

    Haisch, B.; Bowyer, S.; Malina, R. F.

    1993-01-01

    The history of extreme ultraviolet (EUV) astronomy is briefly reviewed, and an overview of the Extreme Ultraviolet Explorer mission, launched into a near-earth (550 km) orbit on June 7, 1992, is presented. First, the principal objective of the mission are summarized. The instrumentation and operation of the mission are then described, with particular attention given to the sky survey instruments, the deep survey instrument, and the spectrometers. The discussion also covers the current view of the interstellar medium, early results from the mission, and future prospects for EUV astronomy.

  10. Prospective EUV observations of hot DA white dwarfs with the EUV Explorer

    NASA Technical Reports Server (NTRS)

    Finley, David S.; Malina, Roger F.; Bowyer, Stuart

    1987-01-01

    The Extreme Ultraviolet Explorer (EUVE) will perform a high sensitivity EUV all-sky survey. A major category of sources which will be detected with the EUVE instruments consists of hot white dwarfs. Detailed preliminary studies of synthetic EUV observations of white dwarfs have been carried out using the predicted EUVE instrumental response functions. Using available information regarding space densities of white dwarfs and the distribution of neutral hydrogen in the interstellar medium, the numbers of DA white dwarfs which will be detectable in the different EUV bandpasses have been estimated.

  11. Arcus: exploring the formation and evolution of clusters, galaxies, and stars

    NASA Astrophysics Data System (ADS)

    Smith, R. K.; Abraham, M.; Allured, R.; Bautz, M.; Bookbinder, J.; Bregman, J.; Brenneman, L.; Brickhouse, N. S.; Burrows, D.; Burwitz, V.; Cheimets, P. N.; Costantini, E.; Dawson, S.; DeRoo, C.; Falcone, A.; Foster, A. R.; Gallo, L.; Grant, C. E.; Günther, H. M.; Heilmann, R. K.; Hertz, E.; Hine, B.; Huenemoerder, D.; Kaastra, J. S.; Kreykenbohm, I.; Madsen, K. K.; McEntaffer, R.; Miller, E.; Miller, J.; Morse, E.; Mushotzky, R.; Nandra, K.; Nowak, M.; Paerels, F.; Petre, R.; Poppenhaeger, K.; Ptak, A.; Reid, P.; Sanders, J.; Schattenburg, M.; Schulz, N.; Smale, A.; Temi, P.; Valencic, L.; Walker, S.; Willingale, R.; Wilms, J.; Wolk, S. J.

    2017-08-01

    Arcus, a Medium Explorer (MIDEX) mission, was selected by NASA for a Phase A study in August 2017. The observatory provides high-resolution soft X-ray spectroscopy in the 12-50Å bandpass with unprecedented sensitivity: effective areas of >450 cm2 and spectral resolution >2500. The Arcus key science goals are (1) to measure the effects of structure formation imprinted upon the hot baryons that are predicted to lie in extended halos around galaxies, groups, and clusters, (2) to trace the propagation of outflowing mass, energy, and momentum from the vicinity of the black hole to extragalactic scales as a measure of their feedback and (3) to explore how stars, circumstellar disks and exoplanet atmospheres form and evolve. Arcus relies upon the same 12m focal length grazing-incidence silicon pore X-ray optics (SPO) that ESA has developed for the Athena mission; the focal length is achieved on orbit via an extendable optical bench. The focused X-rays from these optics are diffracted by high-efficiency Critical-Angle Transmission (CAT) gratings, and the results are imaged with flight-proven CCD detectors and electronics. The power and telemetry requirements on the spacecraft are modest. Mission operations are straightforward, as most observations will be long ( 100 ksec), uninterrupted, and pre-planned, although there will be capabilities to observe sources such as tidal disruption events or supernovae with a 3 day turnaround. Following the 2nd year of operation, Arcus will transition to a proposal-driven guest observatory facility.

  12. Escherichia coli growth changes by the mediated effects after low-intensity electromagnetic irradiation of extremely high frequencies.

    PubMed

    Torgomyan, Heghine; Hovnanyan, Karlen; Trchounian, Armen

    2013-04-01

    Water is the major constituent of environmental medium and biological systems. The effects occurring in water as a result of low-intensity electromagnetic irradiation (EMI) in extremely high frequencies are supposed to be the primary mechanism to create conditions for biological responses. The EMI effects on Escherichia coli, after irradiation of their suspension, are most probably water-mediated. Indirect effects of EMI at 51.8, 53, 70.6, and 73 GHz frequencies on bacteria, through water, assay buffer (Tris-phosphate buffer with inorganic salts at low or moderate concentrations), or peptone growth medium were studied. The mediated effects of 70.6 and 73 GHz irradiated water, assay buffer, and growth medium on E. coli growth characteristics were insignificant. But the results were different for 51.8 and 53 GHz. EMI mediated effects on bacterial growth were clearly demonstrated. The effects were more strongly expressed with 53 GHz. Moreover, it was shown that 70.6 and 73 GHz similarly suppressed the cell growth after direct irradiation of E. coli in water or on solid medium. Interestingly, for 51.8 and 53 GHz the bacterial growth decreases after suspension irradiation was less, compared to the direct irradiation of bacteria on solid medium. Especially, it was also more expressed in case of 53 GHz. Also with electron microscopy, EMI-induced bacterial cell sizes and structure different changes were detected. In addition, the distinguished changes in surface tension, oxidation-reduction potential and pH of water, assay buffer, growth medium, and bacterial suspension were determined. They depended on EMI frequency used. The differences could be associated with the partial absorbance of EMI energy by the surrounding medium, which depends on a specific frequency. The results are crucial to understand biophysical mechanisms of EMI effects on bacteria.

  13. Dissociation of heavy quarkonia in an anisotropic hot QCD medium in a quasiparticle model

    NASA Astrophysics Data System (ADS)

    Jamal, Mohammad Yousuf; Nilima, Indrani; Chandra, Vinod; Agotiya, Vineet Kumar

    2018-05-01

    The present article is the follow-up work of Phys. Rev. D 94, 094006 (2016), 10.1103/PhysRevD.94.094006, where we have extended the study of quarkonia dissociation in (momentum) anisotropic hot QCD medium. As evident by the experimentally observed collective flow at the RHIC and LHC, the momentum anisotropy is present at almost all the stages after the collision, and therefore, it is important to include its effects in the analysis. Employing the in-medium (corrected) potential while considering the anisotropy (both oblate and prolate cases) in the medium, the thermal widths and the binding energies of the heavy quarkonia states (s -wave charmonia and s -wave bottomonia specifically, for radial quantum numbers n =1 and 2) have been determined. The hot QCD medium effects have been included by employing a quasiparticle description. The presence of anisotropy has modified the potential and then the thermal widths and binding energies of these states in a significant manner. The results show a quite visible shift in the values of dissociation temperatures as compared to the isotropic case. Further, the hot QCD medium interaction effects suppress the dissociation temperature as compared to the case where we consider the medium as a noninteracting ultrarelativistic gas of quarks (antiquarks) and gluons.

  14. Molecular Hydrogen Alleviates Cellular Senescence in Endothelial Cells.

    PubMed

    Hara, Fumihiko; Tatebe, Junko; Watanabe, Ippei; Yamazaki, Junichi; Ikeda, Takanori; Morita, Toshisuke

    2016-08-25

    Substantial evidence indicates that molecular hydrogen (H2) has beneficial vascular effects because of its antioxidant and/or anti-inflammatory effects. Thus, hydrogen-rich water may prove to be an effective anti-aging drink. This study examined the effects of H2on endothelial senescence and clarified the mechanisms involved. Hydrogen-rich medium was produced by a high-purity hydrogen gas generator. Human umbilical vein endothelial cells (HUVECs) were incubated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) for various time periods in normal or hydrogen-rich medium. The baseline H2concentration in hydrogen-rich medium was 0.55±0.07 mmol/L. This concentration gradually decreased, and H2was almost undetectable in medium after 12 h. At 24 h after TCDD exposure, HUVECs treated with TCDD exhibited increased 8OHdG and acetyl-p53 expression, decreased nicotinamide adenine dinucleotide (NAD(+))/NADH ratio, impaired Sirt1 activity, and enhanced senescence-associated β-galactosidase. However, HUVECs incubated in hydrogen-rich medium did not exhibit these TCDD-induced changes accompanying Nrf2 activation, which was observed even after H2was undetectable in the medium. Chrysin, an inhibitor of Nrf2, abolished the protective effects of H2on HUVECs. H2has long-lasting antioxidant and anti-aging effects on vascular endothelial cells through the Nrf2 pathway, even after transient exposure to H2. Hydrogen-rich water may thus be a functional drink that increases longevity. (Circ J 2016; 80: 2037-2046).

  15. Dual energy computed tomography for the head.

    PubMed

    Naruto, Norihito; Itoh, Toshihide; Noguchi, Kyo

    2018-02-01

    Dual energy CT (DECT) is a promising technology that provides better diagnostic accuracy in several brain diseases. DECT can generate various types of CT images from a single acquisition data set at high kV and low kV based on material decomposition algorithms. The two-material decomposition algorithm can separate bone/calcification from iodine accurately. The three-material decomposition algorithm can generate a virtual non-contrast image, which helps to identify conditions such as brain hemorrhage. A virtual monochromatic image has the potential to eliminate metal artifacts by reducing beam-hardening effects. DECT also enables exploration of advanced imaging to make diagnosis easier. One such novel application of DECT is the X-Map, which helps to visualize ischemic stroke in the brain without using iodine contrast medium.

  16. Electro-Optic Effects in Colloidal Dispersion of Metal Nano-Rods in Dielectric Fluid

    PubMed Central

    Golovin, Andrii B.; Xiang, Jie; Park, Heung-Shik; Tortora, Luana; Nastishin, Yuriy A.; Shiyanovskii, Sergij V.; Lavrentovich, Oleg D.

    2011-01-01

    In modern transformation optics, one explores metamaterials with properties that vary from point to point in space and time, suitable for application in devices such as an “optical invisibility cloak” and an “optical black hole”. We propose an approach to construct spatially varying and switchable metamaterials that are based on colloidal dispersions of metal nano-rods (NRs) in dielectric fluids, in which dielectrophoretic forces, originating in the electric field gradients, create spatially varying configurations of aligned NRs. The electric field controls orientation and concentration of NRs and thus modulates the optical properties of the medium. Using gold (Au) NRs dispersed in toluene, we demonstrate electrically induced change in refractive index on the order of 0.1. PMID:28879997

  17. Sources of AIDS awareness among women in India.

    PubMed

    Pallikadavath, S; Sreedharan, C; Stones, R W

    2006-01-01

    Sources of AIDS awareness among rural and urban Indian women were analysed using data from the National Family and Health Survey (1998-2000). Two measures were developed to study the impact each source had on knowledge. 'Effectiveness' was defined as the proportion of women who had heard of AIDS from only one source, from among women who had heard of AIDS from that particular source and other sources. 'Independent effect' was the proportion who had heard of AIDS from only one source in relation to all women who had heard of AIDS. Television was the most effective medium, and also had the highest independent effect. Radio and print had very low effectiveness and independent effect. Although television and print audiences are growing in India, it is likely a sub-group of women will continue to lack media access. There is an urgent need to disseminate AIDS awareness to this 'media underclass'. Since the media will not reach this group, other sources including health workers, community level activities such as adult education programmes, and networks of friends and relatives need to be explored.

  18. An experimental strategy validated to design cost-effective culture media based on response surface methodology.

    PubMed

    Navarrete-Bolaños, J L; Téllez-Martínez, M G; Miranda-López, R; Jiménez-Islas, H

    2017-07-03

    For any fermentation process, the production cost depends on several factors, such as the genetics of the microorganism, the process condition, and the culture medium composition. In this work, a guideline for the design of cost-efficient culture media using a sequential approach based on response surface methodology is described. The procedure was applied to analyze and optimize a culture medium of registered trademark and a base culture medium obtained as a result of the screening analysis from different culture media used to grow the same strain according to the literature. During the experiments, the procedure quantitatively identified an appropriate array of micronutrients to obtain a significant yield and find a minimum number of culture medium ingredients without limiting the process efficiency. The resultant culture medium showed an efficiency that compares favorably with the registered trademark medium at a 95% lower cost as well as reduced the number of ingredients in the base culture medium by 60% without limiting the process efficiency. These results demonstrated that, aside from satisfying the qualitative requirements, an optimum quantity of each constituent is needed to obtain a cost-effective culture medium. Study process variables for optimized culture medium and scaling-up production for the optimal values are desirable.

  19. In Vitro Impact of Conditioned Medium From Demineralized Freeze-Dried Bone on Human Umbilical Endothelial Cells.

    PubMed

    Harnik, Branko; Miron, Richard J; Buser, Daniel; Gruber, Reinhard

    2017-03-01

    Angiogenesis is essential for the consolidation of bone allografts. The underlying molecular mechanism, however, remains unclear. Soluble factors released from demineralized freeze-dried bone target mesenchymal cells; however, their effect on endothelial cells has not been investigated so far. The aim of the present study was therefore to examine the effect of conditioned medium from demineralized freeze-dried bone on human umbilical endothelial cells in vitro. Conditioned medium was first prepared from demineralized freeze-dried bone following 24 hours incubation at room temperature to produce demineralized bone conditioned media. Thereafter, conditioned medium was used to stimulate human umbilical vein endothelial cells in vitro by determining the cell response based on viability, proliferation, expression of apoptotic genes, a Boyden chamber to determine cell migration, and the formation of branches. The authors report here that conditioned medium decreased viability and proliferation of endothelial cells. Neither of the apoptotic marker genes was significantly altered when endothelial cells were exposed to conditioned medium. The Boyden chamber revealed that endothelial cells migrate toward conditioned medium. Moreover, conditioned medium moderately stimulated the formation of branches. These findings support the concept that conditioned medium from demineralized freeze-dried bone targets endothelial cells by decreasing their proliferation and enhancing their motility under these in vitro conditions.

  20. Percolation Laws of a Fractal Fracture-Pore Double Medium

    NASA Astrophysics Data System (ADS)

    Zhao, Yangsheng; Feng, Zengchao; Lv, Zhaoxing; Zhao, Dong; Liang, Weiguo

    2016-12-01

    The fracture-pore double porosity medium is one of the most common media in nature, for example, rock mass in strata. Fracture has a more significant effect on fluid flow than a pore in a fracture-pore double porosity medium. Hence, the fracture effect on percolation should be considered when studying the percolation phenomenon in porous media. In this paper, based on the fractal distribution law, three-dimensional (3D) fracture surfaces, and two-dimensional (2D) fracture traces in rock mass, the locations of fracture surfaces or traces are determined using a random function of uniform distribution. Pores are superimposed to build a fractal fracture-pore double medium. Numerical experiments were performed to show percolation phenomena in the fracture-pore double medium. The percolation threshold can be determined from three independent variables (porosity n, fracture fractal dimension D, and initial value of fracture number N0). Once any two are determined, the percolation probability exists at a critical point with the remaining parameter changing. When the initial value of the fracture number is greater than zero, the percolation threshold in the fracture-pore medium is much smaller than that in a pore medium. When the fracture number equals zero, the fracture-pore medium degenerates to a pore medium, and both percolation thresholds are the same.

  1. Oxidative stress gradient in a medium during human corneal organ culture

    PubMed Central

    Johnsen-Soriano, Siv; Haug, Kristiane; Arnal, Emma; Peris-Martinez, Cristina; Moe, Morten C.

    2012-01-01

    Purpose Lipid peroxidation content was measured in an organ culture medium after one-week storage of human donor corneas. Moreover, the effects of the medium on oxidative stress, antioxidant capacity, and the proliferation of cultured human corneal cells were studied. Methods The medium was sampled from the upper and lower halves of storage vials and from controls (n=42). Malondialdehyde (MDA) was measured by high pressure liquid chromatography (HPLC). Cultured human corneal epithelium (CRL-11515) was exposed to different medium samples and monitored for changes in MDA (enzyme-linked immunosorbent assay [ELISA]), total antioxidant capacity (antioxidant assay kit), and proliferation (Ki-67). Results A significant increase in MDA was observed in the organ culture medium in the lower level of storage vials. The addition of this fraction to cultured cells increased MDA significantly after 3 days, and the medium from both levels significantly increased MDA after 7 days. The medium from both levels significantly decreased the total antioxidant capacity of the cells but did not affect proliferative activity. Conclusions An oxidative gradient with an evident biologic effect is established in the medium in vials during organ culture of human donor corneas. Donor tissue stored at the bottom or in lower levels of such vials is exposed to a significant amount of oxidative stress. PMID:22736949

  2. Spermatogonial Culture Medium: An Effective and Efficient Nutrient Mixture for Culturing Rat Spermatogonial Stem Cells1

    PubMed Central

    Wu, Zhuoru; Falciatori, Ilaria; Molyneux, Laura A.; Richardson, Timothy E.; Chapman, Karen M.; Hamra, F. Kent

    2009-01-01

    An economical and simplified procedure to derive and propagate fully functional lines of undifferentiated rat spermatogonia in vitro is presented. The procedure is based on the formulation of a new spermatogonial culture medium termed SG medium. The SG medium is composed of a 1:1 mixture of Dulbecco modified Eagle medium:Ham F12 nutrient, 20 ng/ml of GDNF, 25 ng/ml of FGF2, 100 μM 2-mercaptoethanol, 6 mM l-glutamine, and a 1× concentration of B27 Supplement Minus Vitamin A solution. Using SG medium, six individual spermatogonial lines were derived from the testes of six separate Sprague-Dawley rats. After proliferating over a 120-day period in SG medium, stem cells within the spermatogonial cultures effectively regenerated spermatogenesis in testes of busulfan-treated recipient rats, which transmitted the donor cell haplotype to more than 75% of progeny by natural breeding. Subculturing in SG medium did not require protease treatment and was achieved by passaging the loosely bound spermatogonial cultures at 1:3 dilutions onto fresh monolayers of irradiated DR4 mouse fibroblasts every 12 days. Spermatogonial lines derived and propagated using SG medium were characterized as homogeneous populations of ZBTB16+ DAZL+ cells endowed with spermatogonial stem cell potential. PMID:19299316

  3. Effect of medium osmolarity and taurine on neuritic outgrowth from goldfish retinal explants.

    PubMed

    Cubillán, Lisbeth; Obregón, Francisco; Lima, Lucimey

    2009-01-01

    Taurine stimulates outgrowth of goldfish retinal explants in a concentration- and time-dependent manner, an effect related to calcium movement and protein phosphorylation. Since taurine is an osmoregulator in the central nervous system, and osmolality might influence regeneration, the purpose of this work was to evaluate the possible effect of hypo-osmolality on basal outgrowth and on the trophic action of the amino acid. Accordingly, goldfish retinal explants obtained after crushing the optic nerve were cultured in iso- and hypo-osmotic medium, the latter achieved by diluting the medium 10% 24 and 72 h after plating. The length and density of the neurites, measured after 5 days in culture, were significantly lower in the hypo- than in the iso-osmotic medium. Taurine stimulated the outgrowth under both conditions, but the percentage of increase was greater in iso-osmotic medium. Taurine concentration, determined by HPLC, did not significantly change in explants. Co-administration of beta-alanine and taurine impaired the trophic effect of taurine to a greater extent in the iso- than in hypo-osmotic medium, indicating a possible differential interaction with the taurine transporter which could be altered by osmotic stress. The exact mechanism of outgrowth regulation by hypotonicity requires further clarification, taking into considering possible modification of the taurine transporter.

  4. Phosphate-Catalyzed Hydrogen Peroxide Formation from Agar, Gellan, and κ-Carrageenan and Recovery of Microbial Cultivability via Catalase and Pyruvate.

    PubMed

    Kawasaki, Kosei; Kamagata, Yoichi

    2017-11-01

    Previously, we reported that when agar is autoclaved with phosphate buffer, hydrogen peroxide (H 2 O 2 ) is formed in the resulting medium (PT medium), and the colony count on the medium inoculated with environmental samples becomes much lower than that on a medium in which agar and phosphate are autoclaved separately (PS medium) (T. Tanaka et al., Appl Environ Microbiol 80:7659-7666, 2014, https://doi.org/10.1128/AEM.02741-14). However, the physicochemical mechanisms underlying this observation remain largely unknown. Here, we determined the factors affecting H 2 O 2 formation in agar. The H 2 O 2 formation was pH dependent: H 2 O 2 was formed at high concentrations in an alkaline or neutral phosphate buffer but not in an acidic buffer. Ammonium ions enhanced H 2 O 2 formation, implying the involvement of the Maillard reaction catalyzed by phosphate. We found that other gelling agents (e.g., gellan and κ-carrageenan) also produced H 2 O 2 after being autoclaved with phosphate. We then examined the cultivability of microorganisms from a fresh-water sample to test whether catalase and pyruvate, known as H 2 O 2 scavengers, are effective in yielding high colony counts. The colony count on PT medium was only 5.7% of that on PS medium. Catalase treatment effectively restored the colony count of PT medium (to 106% of that on PS medium). In contrast, pyruvate was not as effective as catalase: the colony count on sodium pyruvate-supplemented PT medium was 58% of that on PS medium. Given that both catalase and pyruvate can remove H 2 O 2 from PT medium, these observations indicate that although H 2 O 2 is the main cause of reduced colony count on PT medium, other unknown growth-inhibiting substances that cannot be removed by pyruvate (but can be by catalase) may also be involved. IMPORTANCE The majority of bacteria in natural environments are recalcitrant to laboratory culture techniques. Previously, we demonstrated that one reason for this is the formation of high H 2 O 2 levels in media prepared by autoclaving agar and phosphate buffer together (PT medium). In this study, we investigated the factors affecting H 2 O 2 formation from agar. H 2 O 2 formation is pH dependent, and ammonium ions promote this phosphate-catalyzed H 2 O 2 formation. Amendment of catalase or pyruvate, a well-known H 2 O 2 -scavenging agent, effectively eliminated H 2 O 2 Yet results suggest that growth-inhibiting factor(s) that cannot be eliminated by pyruvate (but can be by catalase) are present in PT medium. Copyright © 2017 American Society for Microbiology.

  5. Phosphate-Catalyzed Hydrogen Peroxide Formation from Agar, Gellan, and κ-Carrageenan and Recovery of Microbial Cultivability via Catalase and Pyruvate

    PubMed Central

    Kamagata, Yoichi

    2017-01-01

    ABSTRACT Previously, we reported that when agar is autoclaved with phosphate buffer, hydrogen peroxide (H2O2) is formed in the resulting medium (PT medium), and the colony count on the medium inoculated with environmental samples becomes much lower than that on a medium in which agar and phosphate are autoclaved separately (PS medium) (T. Tanaka et al., Appl Environ Microbiol 80:7659–7666, 2014, https://doi.org/10.1128/AEM.02741-14). However, the physicochemical mechanisms underlying this observation remain largely unknown. Here, we determined the factors affecting H2O2 formation in agar. The H2O2 formation was pH dependent: H2O2 was formed at high concentrations in an alkaline or neutral phosphate buffer but not in an acidic buffer. Ammonium ions enhanced H2O2 formation, implying the involvement of the Maillard reaction catalyzed by phosphate. We found that other gelling agents (e.g., gellan and κ-carrageenan) also produced H2O2 after being autoclaved with phosphate. We then examined the cultivability of microorganisms from a fresh-water sample to test whether catalase and pyruvate, known as H2O2 scavengers, are effective in yielding high colony counts. The colony count on PT medium was only 5.7% of that on PS medium. Catalase treatment effectively restored the colony count of PT medium (to 106% of that on PS medium). In contrast, pyruvate was not as effective as catalase: the colony count on sodium pyruvate-supplemented PT medium was 58% of that on PS medium. Given that both catalase and pyruvate can remove H2O2 from PT medium, these observations indicate that although H2O2 is the main cause of reduced colony count on PT medium, other unknown growth-inhibiting substances that cannot be removed by pyruvate (but can be by catalase) may also be involved. IMPORTANCE The majority of bacteria in natural environments are recalcitrant to laboratory culture techniques. Previously, we demonstrated that one reason for this is the formation of high H2O2 levels in media prepared by autoclaving agar and phosphate buffer together (PT medium). In this study, we investigated the factors affecting H2O2 formation from agar. H2O2 formation is pH dependent, and ammonium ions promote this phosphate-catalyzed H2O2 formation. Amendment of catalase or pyruvate, a well-known H2O2-scavenging agent, effectively eliminated H2O2. Yet results suggest that growth-inhibiting factor(s) that cannot be eliminated by pyruvate (but can be by catalase) are present in PT medium. PMID:28821549

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

    Kaurov, Alexander A., E-mail: kaurov@uchicago.edu

    We explore a time-dependent energy dissipation of the energetic electrons in the inhomogeneous intergalactic medium (IGM) during the epoch of cosmic reionization. In addition to the atomic processes, we take into account the inverse Compton (IC) scattering of the electrons on the cosmic microwave background photons, which is the dominant channel of energy loss for electrons with energies above a few MeV. We show that: (1) the effect on the IGM has both local (atomic processes) and non-local (IC radiation) components; (2) the energy distribution between hydrogen and helium ionizations depends on the initial energy of an electron; (3) themore » local baryon overdensity significantly affects the fractions of energy distributed in each channel; and (4) the relativistic effect of the atomic cross-section becomes important during the epoch of cosmic reionization. We release our code as open source for further modification by the community.« less

  7. Food hygiene training in small to medium-sized care settings.

    PubMed

    Seaman, Phillip; Eves, Anita

    2008-10-01

    Adoption of safe food handling practices is essential to effectively manage food safety. This study explores the impact of basic or foundation level food hygiene training on the attitudes and intentions of food handlers in care settings, using questionnaires based on the Theory of Planned Behaviour. Interviews were also conducted with food handlers and their managers to ascertain beliefs about the efficacy of, perceived barriers to, and relevance of food hygiene training. Most food handlers had undertaken formal food hygiene training; however, many who had not yet received training were preparing food, including high risk foods. Appropriate pre-training support and on-going supervision appeared to be lacking, thus limiting the effectiveness of training. Findings showed Subjective Norm to be the most significant influence on food handlers' intention to perform safe food handling practices, irrespective of training status, emphasising the role of important others in determining desirable behaviours.

  8. Application of Monte-Carlo Analyses for the Microwave Anisotropy Probe (MAP) Mission

    NASA Technical Reports Server (NTRS)

    Mesarch, Michael A.; Rohrbaugh, David; Schiff, Conrad; Bauer, Frank H. (Technical Monitor)

    2001-01-01

    The Microwave Anisotropy Probe (MAP) is the third launch in the National Aeronautics and Space Administration's (NASA's) a Medium Class Explorers (MIDEX) program. MAP will measure, in greater detail, the cosmic microwave background radiation from an orbit about the Sun-Earth-Moon L2 Lagrangian point. Maneuvers will be required to transition MAP from it's initial highly elliptical orbit to a lunar encounter which will provide the remaining energy to send MAP out to a lissajous orbit about L2. Monte-Carlo analysis methods were used to evaluate the potential maneuver error sources and determine their effect of the fixed MAP propellant budget. This paper will discuss the results of the analyses on three separate phases of the MAP mission - recovering from launch vehicle errors, responding to phasing loop maneuver errors, and evaluating the effect of maneuver execution errors and orbit determination errors on stationkeeping maneuvers at L2.

  9. An Alternative Medium of Social Education--The "Horrors of War" Picture Cards.

    ERIC Educational Resources Information Center

    Nelson, Murry R.

    1997-01-01

    Explores the production, distribution, and content of the, "Horrors of War," a series of trading cards produced between 1938 and 1942. Created by a Baptist advertising executive the cards used graphic images to communicate an antiwar message to young adolescents. Discusses possible learning activities used in conjunction with the cards.…

  10. Enhancing Intercultural Engagement through Service Learning and Music Making with Indigenous Communities in Australia

    ERIC Educational Resources Information Center

    Bartleet, Brydie-Leigh; Sunderland, Naomi; Carfoot, Gavin

    2016-01-01

    This article explores the potential for music making activities such as jamming, song writing, and performance to act as a medium for intercultural connection and relationship building during service learning programs with Indigenous communities in Australia. To set the context, the paper begins with an overview of current international…

  11. A Case Study of Knowledge Management in the "Back Office" of Two English Football Clubs

    ERIC Educational Resources Information Center

    Doloriert, Clair; Whitworth, Kieran

    2011-01-01

    Purpose: This study aims to explore knowledge management (KM) practice in the "back office" of two English football clubs. Design/methodology/approach: The paper takes the form of a comparative case study of two medium-sized businesses using multi-method data including unstructured interviews, structured questionnaires and document…

  12. Shakespeare, Adaptation and "Matters of Trust"

    ERIC Educational Resources Information Center

    Sabeti, Shari

    2017-01-01

    This article describes an empirical study of the ways in which one group of adaptors transformed the plays of William Shakespeare into the medium of the comic book for use in school classrooms. It explores the choices, dilemmas, processes and responsibilities they experienced in doing so. These adaptors had to tackle the burden of…

  13. The Governing of International Schools: The Implications of Ownership and Profit Motive

    ERIC Educational Resources Information Center

    James, Chris; Sheppard, Paul

    2014-01-01

    There are in excess of 5000 English-medium international schools worldwide. This article reports a study of the governing of such schools that explored in particular the implications of ownership and profit motive. The research entailed a questionnaire-based survey of international school head teachers and interviews with representatives of…

  14. The Politics of Citizenship and Difference in Sri Lankan Schools

    ERIC Educational Resources Information Center

    Sorensen, Birgitte Refslund

    2008-01-01

    This article explores the formation of citizenship in Tamil-medium minority schools in Sri Lanka. It is argued that although the new curriculum aims to construct an inclusive notion of national citizenship, the influence of politics on education in reality creates dominant experiences of discrimination and marginalization. I argue, however, that…

  15. Using Captioned Television To Improve the Reading Proficiency of Language Minority students. Research Study.

    ERIC Educational Resources Information Center

    National Captioning Inst., Inc., Falls Church, VA.

    This study proposed that captioned television, as a multi-sensory, largely entertaining medium might be an important source of comprehensive input for bilingual students in learning language and literacy. To explore this issue, the study investigated the following questions: (1) can bilingual students acquire vocabulary incidentally through…

  16. Childhood Bestiality: A Potential Precursor to Adult Interpersonal Violence

    ERIC Educational Resources Information Center

    Hensley, Christopher; Tallichet, Suzanne E.; Dutkiewicz, Erik L.

    2010-01-01

    Although bestiality is an infrequent form of animal cruelty, the possibility of identifying a potential link between these acts and later interpersonal violence is an area of research that deserves further exploration. In a replication of the Hensley, Tallichet, and Singer study and based on survey data from male inmates at a medium- and…

  17. Employers' Skill Preferences across Europe: Between Cognitive and Non-Cognitive Skills

    ERIC Educational Resources Information Center

    Mýtna Kureková, Lucia; Beblavý, Miroslav; Haita, Corina; Thum, Anna-Elisabeth

    2016-01-01

    This article analyses online job advertisements to identify skills that are demanded in selected low- and medium-skilled occupations. We explore data from the publicly administered cross-European EURES job search portal and quantify the different cognitive and non-cognitive skills requested by employers in small European economies. While we find…

  18. On the Move: Globalising Higher Education in Europe and Beyond

    ERIC Educational Resources Information Center

    Robertson, Susan L.; Kedzierski, Matt

    2016-01-01

    This paper examines the rise and rise of a range of individual, institutional, national and regional mobility projects in the global higher education sector, and explores the implications of these dynamics for the economisation, and thus instrumentalisation, of English as a global language, as a medium of instruction and a competitive advantage.…

  19. Grief Counseling Groups in a Medium-Security Prison

    ERIC Educational Resources Information Center

    Olson, Margaret J.; McEwen, Margaret A.

    2004-01-01

    The authors discuss their facilitation of four grief counseling groups with male inmates in a state prison over a two-year period. Worden's Tasks of Mourning were used as a guide for the group process. Disenfranchised grief and gender and cultural issues in grieving are explored. Catalytic exercises are described, and written feedback from inmates…

  20. Paying Attention to Gesture When Students Talk Chemistry: Interactional Resources for Responsive Teaching

    ERIC Educational Resources Information Center

    Flood, Virginia J.; Amar, Francois G.; Nemirovsky, Ricardo; Harrer, Benedikt W.; Bruce, Mitchell R. M.; Wittmann, Michael C.

    2015-01-01

    When students share and explore chemistry ideas with others, they use gestures and their bodies to perform their understanding. As a publicly visible, spatio-dynamic medium of expression, gestures and the body provide productive resources for imagining the submicroscopic, three-dimensional, and dynamic phenomena of chemistry together. In this…

  1. IDEA: Identifying Design Principles in Educational Applets

    ERIC Educational Resources Information Center

    Underwood, Jody S.; Hoadley, Christopher; Lee, Hollylynne Stohl; Hollebrands, Karen; DiGiano, Chris; Renninger, K. Ann

    2005-01-01

    The Internet is increasingly being used as a medium for educational software in the form of miniature applications (e.g., applets) to explore concepts in a domain. One such effort in mathematics education, the Educational Software Components of Tomorrow (ESCOT) project, created 42 miniature applications each consisting of a context, a set of…

  2. Multimedia Design and Development: Who, What, When, Where, How, and Why.

    ERIC Educational Resources Information Center

    Fox, Michael T.

    An important use of multimedia as a learning tool in academia is the process of designing and developing a multimedia project. The design and development process empowers students to explore, discuss, evaluate, and articulate their knowledge in a richer medium. A journalistic approach to examining the virtues, limitations, and components of the…

  3. Imagining Postnationalism: Arts, Citizenship Education, and Arab American Youth

    ERIC Educational Resources Information Center

    El-Haj, Thea Renda Abu

    2009-01-01

    This article explores an Arab American community arts organization as a site for promoting youth civic participation and social activism. Studying a citizenship education project outside the school walls, and focusing on the arts as a medium for this work, foregrounds the role of the symbolic for engaging youth as active participants in democratic…

  4. A Meta-Analysis of Approaches to Engage Social Work Students Online

    ERIC Educational Resources Information Center

    Farrel, Dorothy; Ray, Kateri; Rich, Telvis; Suarez, Zulema; Christenson, Brian; Jennigs, Lisa

    2018-01-01

    With an increase in social work courses being offered in online and hybrid formats, it is imperative that social work programs understand the new teaching tenets and engagement mediums employed to meet the new Council on Social Work Education's Educational Policy and Accreditation Standards. This meta-analysis explores best-practices pedagogy for…

  5. Teaching Ethics beyond the Academy: Educational Tourism, Lifelong Learning and Phronesis

    ERIC Educational Resources Information Center

    Pitman, Tim; Broomhall, Susan; Majocha, Elzbieta

    2011-01-01

    Universities traditionally construct ethical, as well as educational goals in their mission, which they attempt to promote not only through their graduates, but sometimes directly to the wider community. This study explores how targeting lifelong learners through the medium of educational tourism might be one such way in which universities can…

  6. The Western World in Soviet and Russian Cinema (1946-2016)

    ERIC Educational Resources Information Center

    Fedorov, A. V.

    2017-01-01

    Cinema has always represented a powerful medium for influencing audiences (including in political and ideological ways). Therefore, exploring how the image of the Western world has been transforming in Soviet and Russian films is still relevant today. This study seeks to accomplish the following: define the role and place of the changing portrayal…

  7. Aggregation Bias and the Analysis of Necessary and Sufficient Conditions in fsQCA

    ERIC Educational Resources Information Center

    Braumoeller, Bear F.

    2017-01-01

    Fuzzy-set qualitative comparative analysis (fsQCA) has become one of the most prominent methods in the social sciences for capturing causal complexity, especially for scholars with small- and medium-"N" data sets. This research note explores two key assumptions in fsQCA's methodology for testing for necessary and sufficient…

  8. Storying Environmental Education

    ERIC Educational Resources Information Center

    Blenkinsop, Sean; Judson, Gillian

    2010-01-01

    This paper sets out to explore the role of story in education. Through the employment of story itself as medium the discussion examines how story is currently used in educational settings. The next step is to posit story as a learning tool and curricular heavy-lifter through introduction to the theory of Imaginative Education as proposed by Kieran…

  9. McLuhan at 100: Exploring the Legacy

    ERIC Educational Resources Information Center

    Hlynka, Denis

    2012-01-01

    Marshall McLuhan (1911-1980) is most remembered for his statement "The medium is the message," an aphorism that embraces the theme of this issue of "Educational Technology." McLuhan showed as never before the hidden biases within all technologies. Today, 100 years after his birth, his laws of media and perceptive aphorisms…

  10. Clay Play

    ERIC Educational Resources Information Center

    Rogers, Liz; Steffan, Dana

    2009-01-01

    This article describes how to use clay as a potential material for young children to explore. As teachers, the authors find that their dialogue about the potential of clay as a learning medium raises many questions: (1) What makes clay so enticing? (2) Why are teachers noticing different play and conversation around the clay table as compared to…

  11. Video Pals: An Experiment in Pupil-Generated Video Communication.

    ERIC Educational Resources Information Center

    Wong, Martin R.; Barbatsis, Gretchen S.

    A visual literacy project to explore how children who have had no experience or instruction in the use of television would use the technology as a communication medium is discussed. One second and one fourth grade class were chosen to prepare three videotape "letters" communicating to their counterparts in another school information about their…

  12. A Phenomenological Exploration of Faculty Experiences Using Lecture Capture Systems

    ERIC Educational Resources Information Center

    Vande Voort, Pamela S.

    2013-01-01

    The purpose of this qualitative, phenomenological study was to describe the perceived experiences of faculty who use lecture capture systems in face-to-face class meetings at small and medium-sized, four-year, highly residential, undergraduate colleges and universities with enrollments between 1,000 and 9,999 students. Through audio-recorded…

  13. In Pursuit of Alternatives in ELT Methodology: WebQuests

    ERIC Educational Resources Information Center

    Sen, Ayfer; Neufeld, Steve

    2006-01-01

    Although the Internet has opened up a vast new source of information for university students to use and explore, many students lack the skills to find, critically evaluate and intelligently exploit web-based resources. This problem is accentuated in English-medium universities where students learn and use English as a foreign language. In these…

  14. Communication via Interactive Media: Communication in a New Key?

    ERIC Educational Resources Information Center

    Carveth, Rod

    1996-01-01

    Explores the use of the World Wide Web as an advertising medium--many companies are having difficulties seeing exactly how the Web will fit into their media strategies. Argues that media decision makers need to realize that interactive media are different from traditional media in terms of form and content. (PA)

  15. Focus on Film: Learning through the Movies

    ERIC Educational Resources Information Center

    Considine, David M.; Baker, Frank

    2006-01-01

    This article explores the use of movies as valuable instructional tools. When students are engaged with the content through a medium they love, they learn better and retain more. Incorporating motion pictures as part of classroom instruction has been spurred by the endorsement of both of the major reading and language arts organizations in the…

  16. Exploring Interprofessional Education through a High-Fidelity Human Patient Simulation Scenario: A Mixed Methods Study

    ERIC Educational Resources Information Center

    Rossler, Kelly Lynn

    2013-01-01

    High-fidelity human patient simulation has emerged as a valuable medium to reinforce educational content within programs of nursing. As simulation learning experiences have been identified as augmenting both didactic lecture content and clinical learning, these experiences have expanded to incorporate interprofessional education. Review of…

  17. Diving into the Letters in Poems: Creating Poetry Banners

    ERIC Educational Resources Information Center

    Godston, Daniel

    2006-01-01

    Fifth grade students explore the public and private dimensions of poetry through the medium of poetry banners. The author maintains that poetry belongs in public spaces and serves as a counter to the "junk text" that surrounds us. A poetry banner is a nice addition to other banners and messages that students, teachers, school…

  18. The Community College Website as Virtual Advisor: A Usability Study

    ERIC Educational Resources Information Center

    Margolin, Jonathan; Miller, Shazia Rafiullah; Rosenbaum, James E.

    2013-01-01

    This study explored whether community college websites are a useful medium for providing knowledge relevant to degree completion. Ten community students used one of three community college websites to answer 10 questions about occupational degree programs. A facilitator asked participants to think aloud while using the website to answer these…

  19. Exploring Market and Competitive Intelligence Research as a Source for Enhancing Innovation Capacity

    ERIC Educational Resources Information Center

    Bajaj, Deepak

    2015-01-01

    The purpose of this study was to assess the role of Competitive and Market Intelligence (CI/MI) Research as a potential source for improving the innovation capability of Small and Medium Enterprises (SME's) leading to successful new product/services/processes/capabilities development (Cooper & Edgett, 2002). This report highlights the…

  20. Developing Children and Multicultural Attitudes: The Systemic Psychosocial Influences of Television Portrayals in a Multimedia Society.

    ERIC Educational Resources Information Center

    Berry, Gordon L.

    2003-01-01

    Television can be an important medium for the teaching and learning of the developing child. This article explores how social learning theory and the cross-cultural images and portrayals on television might influence the multicultural attitudes, values, and beliefs of children. (Contains 22 references.) (Author)

  1. The Internationalization of Tertiary Education in Asia: Language, Identity and Conflict

    ERIC Educational Resources Information Center

    Trent, John

    2012-01-01

    This article reports on a qualitative study that examined the identity construction experiences of six international English-language teaching assistants (IELTAs) in a large English medium of instruction university in Hong Kong. The study explored the contribution of the IELTAs to the internationalization goals of the university using a framework…

  2. From Low-Lying Roofs to Towering Spires: Toward a Heideggerian Understanding of Learning Environments

    ERIC Educational Resources Information Center

    Ream, Todd C.; Ream, Tyler W.

    2005-01-01

    This article explores the significance that environments play in terms of the learning process. In the United States, the legacy of John Dewey's intellectual efforts left a theoretical understanding that views the architectural composition of learning environments as instrumental mediums which house the educational process. This understanding of…

  3. SKYLAB (SL)-3 - EXPERIMENT HARDWARE

    NASA Image and Video Library

    1973-11-08

    S74-19675 (1974) --- Medium close-up view of the M512 materials processing equipment storage assembly and the M518 electric furnace in the Multiple Docking Adapter (MDA), one of the primary elements of the Skylab space station. The assembly holds equipment designed to explore space manufacturing capability in a weightless state. Photo credit: NASA

  4. Film in Development.

    ERIC Educational Resources Information Center

    Information Center on Instructional Technology Report, 1976

    1976-01-01

    The positive and negative aspects of using film as a medium for inducing change in developing nations are explored in this issue. Critics of the use of film for development cite (1) the culture specific nature of film content of foreign produced films; (2) the technical, economic, and logistical problems of in-country production; and (3) lack of…

  5. Smartphones and Patient Care: Exploring the Use of Text-Based Messaging for Patient-Related Communication.

    PubMed

    Goldfarb, Jeremy; Kayssi, Ahmed; Devon, Karen; Rossos, Peter G; Cil, Tulin D

    2016-06-01

    Background Text messaging (texting) has become a routine medium of communication in society. However, its use among clinicians has not been fully characterized. We explored general surgery residents' practices and views on texting for patient-related communication. Methods An email survey was distributed to all general surgery residents at a large Canadian medical school. Results Overall, 46 (57%) of those surveyed responded. All used texting for patient-related communication. Eleven percent of residents did not have a password on their cell phone and 89% did not have encrypted phones. Texting was the most common way (41%) by which residents communicated routine patient-related information with staff physicians. Most (85%) residents agreed that texting enhances patient care. The majority (66%) did not know if their hospital had a policy on texting and were unaware of legislation surrounding texting in patient care (89%). Conclusions Most general surgery residents use texting for communication of routine patient-related care issues. However, they acknowledge concerns regarding the security of this medium. © The Author(s) 2016.

  6. A study of large, medium and small scale structures in the topside ionosphere

    NASA Technical Reports Server (NTRS)

    Gross, Stanley H.; Kuo, Spencer P.; Shmoys, Jerry

    1986-01-01

    Alouette and ISIS data were studied for large, medium, and small scale structures in the ionosphere. Correlation was also sought with measurements by other satellites, such as the Atmosphere Explorer C and E and the Dynamic Explorer 2 satellites, of both neutrals and ionization, and with measurements by ground facilities, such as the incoherent scatter radars. Large scale coherent wavelike structures were found from ISIS 2 electron density contours from above the F peak to nearly the satellite altitude. Such structures were also found to correlate with the observation by AE-C below the F peak during a conjunction of the two satellites. Vertical wavefronts found in the upper F region suggest the dominance of diffusion along field lines as well. Also discovered were multiple, evenly spaced field-aligned ducts in the F region that, at low latitudes, extended to the other hemisphere and were in the form of field-aligned sheets in the east-west direction. Low latitude heating events were discovered that could serve as sources for waves in the ionosphere.

  7. Investigation of the Klinkenberg effect in a micro/nanoporous medium by direct simulation Monte Carlo method

    NASA Astrophysics Data System (ADS)

    Yang, Guang; Weigand, Bernhard

    2018-04-01

    The pressure-driven gas transport characteristics through a porous medium consisting of arrays of discrete elements is investigated by using the direct simulation Monte Carlo (DSMC) method. Different porous structures are considered, accounting for both two- and three-dimensional arrangements of basic microscale and nanoscale elements. The pore scale flow patterns in the porous medium are obtained, and the Knudsen diffusion in the pores is studied in detail for slip and transition flow regimes. A new effective pore size of the porous medium is defined, which is a function of the porosity, the tortuosity, the contraction factor, and the intrinsic permeability of the porous medium. It is found that the Klinkenberg effect in different porous structures can be fully described by the Knudsen number characterized by the effective pore size. The accuracies of some widely used Klinkenberg correlations are evaluated by the present DSMC results. It is also found that the available correlations for apparent permeability, most of which are derived from simple pipe or channel flows, can still be applicative for more complex porous media flows, by using the effective pore size defined in this study.

  8. A cost effective cultivation medium for biocalcification of Bacillus pasteurii KCTC 3558 and its effect on cement cubes properties.

    PubMed

    Yoosathaporn, S; Tiangburanatham, P; Bovonsombut, S; Chaipanich, A; Pathom-Aree, W

    2016-01-01

    Application of carbonate precipitation induced by Bacillus pasteurii for improving some properties of cement has been reported. However, it is not yet successful in commercial scale due to the high cost of cultivation medium. This is the first report on the application of effluent from chicken manure bio-gas plant, a high protein content agricultural waste, as an alternative growth medium for carbonate precipitation by B. pasteurii KCTC3558. Urease activity of B. pasteurii KCTC3558 cultured in chicken manure effluent medium and other three standard media were examined using phenate method. The highest urease production was achieved in chicken manure effluent medium (16.756Umg(-1) protein). Cost per liter of chicken manure effluent medium is up to 88.2% lower than other standard media. The most effective cultivation media was selected for carbonate precipitation study in cement cubes. Water absorption, voids, apparent density and compressive strength of cement cubes were measured according to the ASTM standard. The correlation between the increasing density and compressive strength of bacterial added cement cube was evident. The density of bacterial cement cube is 5.1% higher than control while the compressive strength of cement mixed with bacterial cells in chicken manure effluent medium increases up to 30.2% compared with control. SEM and XRD analysis also found the crystalline phase of calcium carbonate within bacterial cement which confirmed that the increasing density and compressive strength were resulted from bacterial carbonate precipitation. This study indicated that the effluent from chicken manure bio-gas plant could be used as an alternative cost effective culture medium for cultivation and biocalcification of B. pasteurii KCTC3558 in cement. Copyright © 2016. Published by Elsevier GmbH.

  9. Effects of a meal rich in medium-chain saturated fat on postprandial lipemia in relatives of type 2 diabetics.

    PubMed

    Pietraszek, Anna; Hermansen, Kjeld; Pedersen, Steen B; Langdahl, Bente L; Holst, Jens J; Gregersen, Søren

    2013-01-01

    Patients with type 2 diabetes and their relatives (REL) have increased risk for cardiovascular disease (CVD). Postprandial triglyceridemia (PPL), which is influenced by diet, is an independent risk factor for CVD. Little is known about the effects of medium-chain saturated fatty acids (medium-chain SFA) on PPL and gene expression in REL. The objective of this study was to test the hypothesis that medium-chain SFA cause larger PPL response in REL compared with controls (CON) and have a differential effect on circulating incretins and ghrelin and gene expression in muscle and adipose tissue in REL and CON. Seventeen REL and 17 CON received a fat-rich meal (79 energy percent from fat) based on medium-chain SFA (coconut oil). Plasma concentrations of triglycerides (TG), free-fatty acids, insulin, glucose, glucagon-like peptide-1, glucose-dependent insulintropic peptide, and ghrelin were measured before and during 240 min postprandially. Muscle and adipose tissue biopsies were taken at baseline and after the test meal. After the test meal, REL had a higher plasma TG response (P = 0.002) and a tendency toward higher insulin response (P = 0.100). A number of genes were upregulated in response to the meal rich in medium-chain SFA in CON, but not in REL. A meal high in medium-chain SFA resulted in larger PPL response in REL than in CON. It remains to be clarified whether this can be reproduced by a pure medium-chain fat (MCT) load. The meal exerted a differential effect on gene expression in muscle, but not adipose tissue, of REL compared with CON. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. "New" Vistas for Polarimetric Exploration

    NASA Astrophysics Data System (ADS)

    Yanamandra-Fisher, P. A.

    2016-12-01

    The versatility of polarimetric exploration is exploited to address the overarching goals for the remote sensing and robotic exploration of our solar system and exoplanetary systems: (1) understanding the formation of planetary systems and their diversity; and (2) search for habitability. Spectral dependence of polarization is important to separate the macroscopic (bulk) properties of the scattering medium from the microscopic (particulate) properties of the scattering medium. While linear polarization of reflected light by solar system objects provides insight into the scattering characteristics of aerosols and hazes in atmospheres and surficial properties of atmosphereless objects, circular polarization and related chirality (or handedness, a property of molecules that exhibit mirror-image symmetry, similar to right and left hands) can serve as diagnostic of biological activity. Most solar system polarimetric exploration is dominantly the study of cometary and asteroidal dust/regoliths. However, efforts are starting to emerge as "new" directions in this field: from recent studies of outer planetary atmospheres and satellites; polarization of magnetic field lines; addressing taxonomy of asteroids and including amateur astronomers. Although current solar system missions do not have polarimeters on-board, ground-based polarimetric observations prove to valuable and complementary. For example, NASA/JUNO lacks a polarimeter in its payload, and one of its goals is to understand Jupiter's aurorae. Recent ground-based observations from NASA/IRTF indicate that the auroral H3+ line is polarized (Barthelemy et al., 2011, A&A, 530). Another new direction for polarimetric exploration is the inclusion of amateur astronomers. Imaging and spectroscopy are routinely performed by amateurs, but recently, there is interest in developing polarimetric exploration amongst the amateur community, such as the study of polarization of the moon (Fearnside et al., 2016, Icarus). I will present a review of the field, with advances made in instrumentation, measurements and efforts to develop a "Polarimetry Network" of observers, modelers and instrument experts to expand and fully utilize polarimetery in the remote sensing of planetary systems.

  11. Exploring Crisis Management in U.S. Small Businesses

    NASA Astrophysics Data System (ADS)

    Williams, Jon

    As a critical infrastructure, the US electricity grid supplies electricity to 340 million people within eight separate regions. The power infrastructure is vulnerable to many types of disasters capable of severing supplies of electricity. The impact on the employees and communities when small- and medium-size enterprises are shut down due to disasters can be severe. The purpose of the quantitative comparative study was to explore small- and medium-size enterprises crisis management strategies in the case of power infrastructure vulnerabilities. Perceptions of small business leaders were probed about crisis management planning relevant to three secondary factors: prior experience of crises, threat perceptions, and planning self-efficacy. Participants completed an adapted questionnaire instrument based on a five-point Likert scale for six sub-factors including resilience through planning, financial impact, operational crisis management, the perfect storm, the aftermath of survival, and atrophy. The instrument also measured three additional factors to include, prior experience of crises, threat perceptions, and planning self-efficacy, across seven types of crises. The results of this study indicated that of the 276 respondents, 104 had no crisis plans, but 172 did have crisis plans. Of those who had implemented crisis plans, 19% had specific provisions to address power outages or attacks on the electrical grid. Of the respondents who had not planned for power outages nor experienced significant losses of power, a statistically significant number acknowledged an external threat to their business. The majority of respondents indicated that long-term planning was related to resilience; however, the migration of crisis understanding into the planning process or implementation was not implemented. This heightened awareness of potential crises without the corresponding development and implementation of mitigation crisis plans requires additional research to understand drivers effecting the decision making process with crisis managers.

  12. Remote acoustic sensing as a safety mechanism during exposure of metal implants to alternating magnetic fields

    PubMed Central

    Chatzinoff, Yonatan; Szczepanski, Debby; Bing, Chenchen; Shaikh, Sumbul; Wyman, Omar; Perry, Cameron E.; Richardson, James A.; Burns, Dennis K.; Evers, Bret M.; Greenberg, David E.; Chopra, Rajiv

    2018-01-01

    Treatment of prosthetic joint infections often involves multiple surgeries and prolonged antibiotic administration, resulting in a significant burden to patients and the healthcare system. We are exploring a non-invasive method to eradicate biofilm on metal implants utilizing high-frequency alternating magnetic fields (AMF) which can achieve surface induction heating. Although proof-of-concept studies demonstrate the ability of AMF to eradicate biofilm in vitro, there is a legitimate safety concern related to the potential for thermal damage to surrounding tissues when considering heating implanted metal objects. The goal of this study was to explore the feasibility of detecting acoustic emissions associated with boiling at the interface between a metal implant and surrounding soft tissue as a wireless safety sensing mechanism. Acoustic emissions generated during in vitro and in vivo AMF exposures were captured with a hydrophone, and the relationship with surface temperature analyzed. The effect of AMF exposure power, surrounding media composition, implant location within the AMF transmitter, and implant geometry on acoustic detection during AMF therapy was also evaluated. Acoustic emissions were reliably identified in both tissue-mimicking phantom and mouse studies, and their onset coincided with the implant temperature reaching the boiling threshold. The viscosity of the surrounding medium did not impact the production of acoustic emissions; however, emissions were not present when the medium was oil due to the higher boiling point. Results of simulations and in vivo studies suggest that short-duration, high-power AMF exposures combined with acoustic sensing can be used to minimize the amount of thermal damage in surrounding tissues. These studies support the hypothesis that detection of boiling associated acoustic emissions at a metal/tissue interface could serve as a real-time, wireless safety indicator during AMF treatment of biofilm on metallic implants. PMID:29746579

  13. Remote acoustic sensing as a safety mechanism during exposure of metal implants to alternating magnetic fields.

    PubMed

    Cheng, Bingbing; Chatzinoff, Yonatan; Szczepanski, Debby; Bing, Chenchen; Shaikh, Sumbul; Wyman, Omar; Perry, Cameron E; Richardson, James A; Burns, Dennis K; Evers, Bret M; Greenberg, David E; Chopra, Rajiv

    2018-01-01

    Treatment of prosthetic joint infections often involves multiple surgeries and prolonged antibiotic administration, resulting in a significant burden to patients and the healthcare system. We are exploring a non-invasive method to eradicate biofilm on metal implants utilizing high-frequency alternating magnetic fields (AMF) which can achieve surface induction heating. Although proof-of-concept studies demonstrate the ability of AMF to eradicate biofilm in vitro, there is a legitimate safety concern related to the potential for thermal damage to surrounding tissues when considering heating implanted metal objects. The goal of this study was to explore the feasibility of detecting acoustic emissions associated with boiling at the interface between a metal implant and surrounding soft tissue as a wireless safety sensing mechanism. Acoustic emissions generated during in vitro and in vivo AMF exposures were captured with a hydrophone, and the relationship with surface temperature analyzed. The effect of AMF exposure power, surrounding media composition, implant location within the AMF transmitter, and implant geometry on acoustic detection during AMF therapy was also evaluated. Acoustic emissions were reliably identified in both tissue-mimicking phantom and mouse studies, and their onset coincided with the implant temperature reaching the boiling threshold. The viscosity of the surrounding medium did not impact the production of acoustic emissions; however, emissions were not present when the medium was oil due to the higher boiling point. Results of simulations and in vivo studies suggest that short-duration, high-power AMF exposures combined with acoustic sensing can be used to minimize the amount of thermal damage in surrounding tissues. These studies support the hypothesis that detection of boiling associated acoustic emissions at a metal/tissue interface could serve as a real-time, wireless safety indicator during AMF treatment of biofilm on metallic implants.

  14. Conditioned medium as a strategy for human stem cells chondrogenic differentiation.

    PubMed

    Alves da Silva, M L; Costa-Pinto, A R; Martins, A; Correlo, V M; Sol, P; Bhattacharya, M; Faria, S; Reis, R L; Neves, Nuno M

    2015-06-01

    Paracrine signalling from chondrocytes has been reported to increase the synthesis and expression of cartilage extracellular matrix (ECM) by stem cells. The use of conditioned medium obtained from chondrocytes for stimulating stem cells chondrogenic differentiation may be a very interesting alternative for moving into the clinical application of these cells, as chondrocytes could be partially replaced by stem cells for this type of application. In the present study we aimed to achieve chondrogenic differentiation of two different sources of stem cells using conditioned medium, without adding growth factors. We tested both human bone marrow-derived mesenchymal stem cells (hBSMCs) and human Wharton's jelly-derived stem cells (hWJSCs). Conditioned medium obtained from a culture of human articular chondrocytes was used to feed the cells during the experiment. Cultures were performed in previously produced three-dimensional (3D) scaffolds, composed of a blend of 50:50 chitosan:poly(butylene succinate). Both types of stem cells were able to undergo chondrogenic differentiation without the addition of growth factors. Cultures using hWJSCs showed significantly higher GAGs accumulation and expression of cartilage-related genes (aggrecan, Sox9 and collagen type II) when compared to hBMSCs cultures. Conditioned medium obtained from articular chondrocytes induced the chondrogenic differentiation of MSCs and ECM formation. Obtained results showed that this new strategy is very interesting and should be further explored for clinical applications. Copyright © 2013 John Wiley & Sons, Ltd.

  15. Childhood cancer mortality and radon concentration in drinking water in North Carolina.

    PubMed Central

    Collman, G. W.; Loomis, D. P.; Sandler, D. P.

    1991-01-01

    We explored the association between groundwater radon levels and childhood cancer mortality in North Carolina. Using data from two state-wide surveys of public drinking water supplies, counties were ranked according to average groundwater radon concentration. Age and sex-adjusted 1950-79 cancer death rates among children under age 15 were calculated for counties with high, medium, and low radon levels. Overall cancer mortality was increased in counties with medium and high radon levels. The strongest association was for the leukaemias, but risks were also suggested for other sites. These associations could be due to confounding or other biases, but the findings are consistent with other recent reports. PMID:2021549

  16. Childhood cancer mortality and radon concentration in drinking water in North Carolina.

    PubMed

    Collman, G W; Loomis, D P; Sandler, D P

    1991-04-01

    We explored the association between groundwater radon levels and childhood cancer mortality in North Carolina. Using data from two state-wide surveys of public drinking water supplies, counties were ranked according to average groundwater radon concentration. Age and sex-adjusted 1950-79 cancer death rates among children under age 15 were calculated for counties with high, medium, and low radon levels. Overall cancer mortality was increased in counties with medium and high radon levels. The strongest association was for the leukaemias, but risks were also suggested for other sites. These associations could be due to confounding or other biases, but the findings are consistent with other recent reports.

  17. Connection of the solar wind with the interstellar medium through numerical modeling

    DOE PAGES

    Heerikhuisen, J.; Zirnstein, E.; Kawamura, A. D.; ...

    2013-06-13

    In this article we investigate the interaction between the solar wind (SW) and the local interstellar medium (LISM) using spacecraft data and numerical simulations. In particular, we focus on neutral atom results from NASA's Interstellar Boundary EXplorer (IBEX) mission, and compare these with implementations of our neutral atom models that look at both the energetic neutral atoms (ENAs) which are created as hydrogen of LISM origin interacts with the heliosphere, as well as the transmission of interstellar Oxygen through the heliospheric interface. Lastly, the goal of this work is to better understand the global structure of the heliosphere and itsmore » interaction with the galaxy.« less

  18. What affects the innovation performance of small and medium-sized enterprises (SMEs) in the biotechnology industry? An empirical study on Korean biotech SMEs.

    PubMed

    Kang, Kyung-Nam; Lee, Yoon-Sik

    2008-10-01

    Research-intensive small and medium-sized enterprises (SMEs) play a crucial role in the advancement of the biotechnology industry. This paper explored the impacts of internal and contextual variables on innovative activity in Korea and compared the results of this analysis with previous studies of other countries. Our analysis of 149 Korean biotech SMEs showed that the ratio of R&D expenditure to sales, the ratio of R&D employees to total employees, CEO characteristics, governmental support and international networking are positively correlated with a firm's innovation performance. The results may help decision makers to better foster SMEs in the Korean biotechnology industry.

  19. Electronically commutated dc motors for electric vehicles

    NASA Technical Reports Server (NTRS)

    Maslowski, E. A.

    1981-01-01

    A motor development program to explore the feasibility of electronically commutated dc motors (also known as brushless) for electric cars is described. Two different design concepts and a number of design variations based on these concepts are discussed. One design concept is based on a permanent magnet, medium speed, machine rated at 7000 to 9000 rpm, and powered via a transistor inverter power conditioner. The other concept is based on a permanent magnet, high speed, machine rated at 22,000 to 26,000 rpm, and powered via a thyristor inverter power conditioner. Test results are presented for a medium speed motor and a high speed motor each of which have been fabricated using samarium cobalt permanent magnet material.

  20. Very High Specific Energy, Medium Power Li/CFx Primary Battery for Launchers and Space Probes

    NASA Astrophysics Data System (ADS)

    Brochard, Paul; Godillot, Gerome; Peres, Jean Paul; Corbin, Julien; Espinosa, Amaya

    2014-08-01

    Benchmark with existing technologies shows the advantages of the lithium-fluorinated carbon (Li/CFx) technology for use aboard future launchers in terms of a low Total Cost of Ownership (TCO), especially for high energy demanding missions such as re-ignitable upper stages for long GTO+ missions and probes for deep space exploration.This paper presents the new results obtained on this chemistry in terms of electrical and climatic performances, abuse tests and life tests. Studies - co-financed between CNES and Saft - looked at a pure CFx version with a specific energy up to 500 Wh/kg along with a medium power of 80 to 100 W/kg.

  1. Family Caregivers of Liver Transplant Recipients: Coping Strategies Associated With Different Levels of Post-traumatic Growth.

    PubMed

    Pérez-San-Gregorio, M Á; Martín-Rodríguez, A; Borda-Mas, M; Avargues-Navarro, M L; Pérez-Bernal, J; Gómez-Bravo, M Á

    2018-03-01

    Analyze the influence of 2 variables (post-traumatic growth and time since liver transplantation) on coping strategies used by the transplant recipient's family members. In all, 218 family members who were their main caregivers of liver transplant recipients were selected. They were evaluated using the Posttraumatic Growth Inventory and the Brief COPE. A 3 × 3 factorial analysis of variance was used to analyze the influence that post-traumatic growth level (low, medium, and high) and time since transplantation (≤3.5 years, >3.5 to ≤9 years, and >9 years) exerted on caregiver coping strategies. No interactive effects between the two factors in the study were found. The only significant main effect was the influence of the post-traumatic growth factor on the following variables: instrumental support (P = .007), emotional support (P = .005), self-distraction (P = .006), positive reframing (P = .000), acceptance (P = .013), and religion (P = <.001). According to the most relevant effect sizes, low post-traumatic growth compared with medium growth was associated with less use of self-distraction (P = .006, d = -0.52, medium effect size), positive reframing (P = .001, d = -0.62, medium effect size), and religion (P = .000, d = -0.66, medium effect size), and in comparison with high growth, it was associated with less use of positive reframing (P = .002, d = -0.56, medium effect size) and religion (P = .000, d = 0.87, large effect size). Regardless of the time elapsed since the stressful life event (liver transplantation), family members with low post-traumatic growth usually use fewer coping strategies involving a positive, transcendent vision to deal with transplantation. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Osthole Attenuates Inflammatory Responses and Regulates the Expression of Inflammatory Mediators in HepG2 Cells Grown in Differentiated Medium from 3T3-L1 Preadipocytes.

    PubMed

    Wu, Shu-Ju

    2015-09-01

    This study explored the anti-inflammatory mechanisms by which osthole acted on HepG2 cells cultured in a differentiated medium from cultured 3T3-L1 preadipocyte cells. HepG2 cells, a human liver cell line, were treated with various concentrations of osthole in differentiated media from cultured 3T3-L1 cells to evaluate proinflammatory cytokines, inflammatory mediators, and signaling pathways. We used enzyme-linked immunosorbent assay kits to determine the levels of proinflammatory cytokines, real-time polymerase chain reaction to assay the mRNA expression, and western blot to determine the expression of cyclooxygenase-2 (COX-2) and heme oxygenase-1 (HO-1) proteins. We also investigated inflammatory mechanism pathway members, including mitogen-activated protein kinase (MAPK) and nuclear transcription factor kappa-B (NF-κB). Osthole was able to suppress the levels of proinflammatory cytokines interleukin (IL)-1β and IL-6, as well as chemokines monocyte chemoattractant protein-1 and IL-8. In addition, COX-2 was suppressed and HO-1 expression was increased in a concentration-dependent manner. Osthole was also able to decrease IκB-α phosphorylation and suppress the phosphorylation of MAPKs. These results suggest that osthole has anti-inflammatory effects as demonstrated by the decreased proinflammatory cytokine and mediator production through suppression of the NF-κB and MAPK signaling pathways in HepG2 cells when they are incubated on the differentiated medium from 3T3-L1 cells.

  3. Low-frequency dispersion and attenuation in anisotropic partially saturated rocks

    NASA Astrophysics Data System (ADS)

    Cavallini, Fabio; Carcione, José M.; Vidal de Ventós, Daniel; Engell-Sørensen, Lisbeth

    2017-06-01

    The mesoscopic-loss mechanism is believed to be the most important attenuation mechanism in porous media at seismic frequencies. It is caused by P-wave conversion to slow diffusion (Biot) modes at material inhomogeneity on length scales of the order of centimetres. It is very effective in partially saturated media, particularly in the presence of gas. We explicitly extend the theory of wave propagation at normal incidence to three periodic thin layers and using this result we obtain the five complex and frequency-dependent stiffness components of the corresponding periodic finely layered medium, where the equivalent medium is anisotropic, specifically transversely isotropic. The relaxation behaviour can be described by a single complex and frequency-dependent stiffness component, since the medium consists of plane homogeneous layers. The media can be dissimilar in any property, but a relevant example in hydrocarbon exploration is the case of partial saturation and the same frame skeleton, where the fluid can be brine, oil and gas. The numerical examples illustrate the implementation of the theory to compute the wave velocities (phase and energy) and quality factors. We consider two main cases, namely, the same frame (or skeleton) and different fluids, and the same fluid and different frame properties. Unlike the two-phase case (two fluids), the results show two relaxation peaks. This scenario is more realistic since usually reservoirs rocks contain oil, brine and gas. The theory is quite general since it is not only restricted to partial saturation, but also applies to important properties such as porosity and permeability heterogeneities.

  4. The influence of naphthaleneacetic acid (NAA) and coumarin on flavonoid production by fungus Phellinus sp.: modeling of production kinetic profiles.

    PubMed

    Ma, Xiao-Kui; Li, Le; Peterson, Eric Charles; Ruan, Tingting; Duan, Xiaoyi

    2015-11-01

    For the purpose of improving the fungal production of flavonoids, the influence of naphthaleneacetic acid (NAA) and coumarin on flavonoid production by fungus Phellinus sp. P0988 was investigated by developing the corresponding kinetics of flavonoid production in a 7-L bioreactor. Phellinus sp. was confirmed to form flavonoids in pellets and broth when cultivated in basic medium, and the optimum concentration of NAA and coumarin in medium for flavonoid production were determined to be 0.03 and 0.02 g/L, respectively. The developed unstructured mathematical models were in good agreement with the experimental results with respect to flavonoid production kinetic profiles with NAA and coumarin supplementation at optimum levels and revealed significant accuracy in terms of statistical consistency and robustness. Analysis of these kinetic processes indicated that NAA and coumarin supplementations imposed a stronger positive influence on flavonoid production and substrate consumption compared to their effects on cell growth. The separate addition of NAA and coumarin resulted in enhancements in final product accumulation and productivity, achieving final flavonoid concentrations of 3.60 and 2.75 g/L, respectively, and glucose consumption showed a significant decrease compared to the non-supplemented control as well. Also, the separate presence of NAA and coumarin respectively decreased maintenance coefficients (M s) from 2.48 in the control to 1.39 and 0.22, representing decreases of 43.9 and 91.1 %, respectively. The current study is the first known application of mathematical kinetic models to explore the influence of medium components adding on flavonoid production by fungi.

  5. The effect of dissipative inhomogeneous medium on the statistics of the wave intensity

    NASA Technical Reports Server (NTRS)

    Saatchi, Sasan S.

    1993-01-01

    One of the main theoretical points in the theory of wave propagation in random medium is the derivation of closed form equations to describe the statistics of the propagating waves. In particular, in one dimensional problems, the closed form representation of the multiple scattering effects is important since it contributes in understanding such problems like wave localization, backscattering enhancement, and intensity fluctuations. In this the propagation of plane waves in a layer of one-dimensional dissipative random medium is considered. The medium is modeled by a complex permittivity whose real part is a constant representing the absorption. The one dimensional problem is mathematically equivalent to the analysis of a transmission line with randomly perturbed distributed parameters and a single mode lossy waveguide and the results can be used to study the propagation of radio waves through atmosphere and the remote sensing of geophysical media. It is assumed the scattering medium consists of an ensemble of one-dimensional point scatterers randomly positioned in a layer of thickness L with diffuse boundaries. A Poisson impulse process with density lambda is used to model the position of scatterers in the medium. By employing the Markov properties of this process an exact closed form equation of Kolmogorov-Feller type was obtained for the probability density of the reflection coefficient. This equation was solved by combining two limiting cases: (1) when the density of scatterers is small; and (2) when the medium is weakly dissipative. A two variable perturbation method for small lambda was used to obtain solutions valid for thick layers. These solutions are then asymptotically evaluated for small dissipation. To show the effect of dissipation, the mean and fluctuations of the reflected power are obtained. The results were compared with a lossy homogeneous medium and with a lossless inhomogeneous medium and the regions where the effect of absorption is not essential were discussed.

  6. Effect of limonene on the heterotrophic growth and polyhydroxybutyrate production by Cupriavidus necator H16.

    PubMed

    Guzman Lagunes, F; Winterburn, J B

    2016-12-01

    The inhibitory effect of limonene on polyhydroxybutyrate (PHB) production in Cupriavidus necator H16 was studied. Firstly, results demonstrate the feasibility of using orange juicing waste (OJW) as a substrate for PHB production. An intracellular PHB content of 81.4% (w/w) was attained for a total dry matter concentration of 9.58gL -1 , when the OJW medium was used. Later, a mineral medium designed to mimic the nutrient levels found in the complex medium derived from OJW was used to study the effect of limonene on the production of PHB. Results showed a drop in specific growth rate (μ) of more than 50% when the initial limonene concentration was 2% (v/v) compared to the limonene free medium. This work highlights the importance of a limonene recovery stage prior to fermentation, to maintain levels below 1% (v/v) in the medium, adding value to the OJW and enhancing the fermentation process productivity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Effects of temperature and medium composition on inhibitory activities of gossypol-related compounds against aflatoxigenic fungi.

    PubMed

    Mellon, J E; Dowd, M K; Beltz, S B

    2013-07-01

    To investigate the effects of temperature and medium composition on growth/aflatoxin inhibitory activities of terpenoids gossypol, gossypolone and apogossypolone against Aspergillus flavus and A. parasiticus. The compounds were tested at a concentration of 100 μg ml(-1) in a Czapek Dox (Czapek) agar medium at 25, 31 and 37°C. Increased incubation temperature marginally increased growth inhibition caused by these compounds, but reduced the aflatoxin inhibition effected by gossypol. Gossypolone and apogossypolone retained good aflatoxin inhibitory activity against A. flavus and A. parasiticus at higher incubation temperatures. However, increased temperature also significantly reduced aflatoxin production in control cultures. The effects of the terpenoids on fungal growth and aflatoxin production against the same fungi were also determined in Czapek, Czapek with a protein/amino acid addendum and yeast extract sucrose (YES) media. Growth of these fungi in the protein-supplemented Czapek medium or in the YES medium greatly reduced the growth inhibition effects of the terpenoids. Apogossypolone displayed strong anti-aflatoxigenic activity in the Czapek medium, but this activity was significantly reduced in the protein-amended Czapek and YES media. Gossypol, which displayed little to no aflatoxin inhibitory activity in the Czapek medium, did yield significant anti-aflatoxigenic activity in the YES medium. Incubation temperature and media composition are important parameters involved in the regulation of aflatoxin production in A. flavus and A. parasiticus. These parameters also affect the potency of growth and aflatoxin inhibitory activities of these gossypol-related compounds against aflatoxigenic fungi. Studies utilizing gossypol-related compounds as inhibitory agents of biological activities should be interpreted with caution due to compound interaction with multiple components of the test system, especially serum proteins. Published [2013]. This article is a U.S. Government work and is in the public domain in the USA.

  8. Online monitoring of electrocatalytic reactions of alcohols at platinum and gold electrodes in acidic, neutral and alkaline media by capillary electrophoresis with contactless conductivity detection (EC-CE-C4 D).

    PubMed

    Ferreira Santos, Mauro Sérgio; Silva Lopes, Fernando; Gutz, Ivano Gebhardt Rolf

    2017-11-01

    An EC-CE-C 4 D flow system was applied to the investigation of electrocatalytic processes by monitoring carboxylic acids formed during the electro-oxidation at various potentials of primary alcohols (mixture of 1 mmol/L of ethanol, n-propanol, n-butanol and n-pentanol) in acidic, neutral and alkaline media. The electro-oxidation was carried out on gold and platinum disk electrodes (3 mm of diameter) in a thin-layer electrochemical flow cell. Products were sampled 50 μm apart from the electrode directly into the capillary. All the generated carboxylates were determined in near real time (less than 2 min) by CE-C 4 D in counter-flow mode, with Tris/HCl buffer solution (pH 8.6) as BGE. Long sequences of 5-min experiments were run automatically, exploring the applied potential, electrolysis time and solution composition. Electro-oxidation at 1.5 V (versus Ag/AgCl quasi-reference) during 50 s in acidic medium was found appropriate for both Pt and Au electrodes when the determination of alcohols after derivatization is intended. A noteworthy selectivity effect was observed on the Au electrode. The signal corresponding to pentanoate is similar on both electrodes while the signal of ethanoate (acetate) is four times larger on gold than on platinum. The carboxylate signals were lower in alkaline medium (below the determination limit on Pt) than in acidic and neutral media. On gold, the formation of carboxylates was anticipated (0.85 V in alkaline medium versus 1.40 V in neutral medium). The automatic online monitoring of electrochemical processes by EC-CE-C 4 D holds great potential to investigate ionic/ionizable intermediates/products of new electrocatalysts and/or alternative fuels. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Decolorization of acid, disperse and reactive dyes by Trametes versicolor CBR43.

    PubMed

    Yang, Seung-Ok; Sodaneath, Hong; Lee, Jung-In; Jung, Hyekyeng; Choi, Jin-Hee; Ryu, Hee Wook; Cho, Kyung-Suk

    2017-07-29

    The mycoremediation has been considered as a promising method for decolorizing dye wastewater. To explore new bioresource for mycoremediation, a new white-rot fungus that could decolorize various dyes commonly used in textile industries was isolated, and its ligninolytic enzyme activity and decolorization capacity were characterized. The isolated CBR43 was identified as Trametes versicolor based on the morphological properties of its fruit body and spores, as well as through partial 18S rDNA gene sequences. Isolated CBR43 displayed high activities of laccase and Mn-dependent peroxidase, whereas its lignin peroxidase activity was relatively low. These ligninolytic enzyme activities in potato dextrose broth (PDB) medium were enhanced by the addition of yeast extract (1-10 g L -1 ). In particular, lignin peroxidase activity was increased more than 5 times in the PDB medium amended with 10 g L -1 of yeast extract. The CBR43 decolorized more than 90% of 200 mg L -1 acid dyes (red 114, blue 62 and black 172) and reactive dyes (red 120, blue 4, orange 16 and black 5) within 6 days in the PDB medium. CBR43 decolorized 67% of 200 mg L -1 acid orange 7 within 9 days. The decolorization efficiencies for disperse dyes (red 1, orange 3 and black 1) were 51-80% within 9 days. The CBR43 could effectively decolorize high concentrations of acid blue 62 and acid black 172 (500-700 mg L -1 ). The maximum dye decolorization rate was obtained at 28°C, pH 5, and 150 rpm in the PDB medium. T. versicolor CBR43 had high laccase and Mn-dependent peroxidase activities, and could decolorize a wide variety of dyes such as acid, disperse and reactive textile dyes. This fungus had decolorizing activities of azo-type dyes as well as anthraquinone-type dyes. T. versicolor CBR43 is one of promising bioresources for the decolorization of textile wastewater including various dyes.

  10. Wood ash residue causes a mixture of growth promotion and toxicity in Lemna minor.

    PubMed

    Jagodzinski, Lucas S; O'Donoghue, Marian T; Heffernan, Liam B; van Pelt, Frank N A M; O'Halloran, John; Jansen, Marcel A K

    2018-06-01

    The use of wood as a sustainable biofuel results in the generation of residual wood ash. The ash contains high amounts of plant macronutrients such as phosphorus, potassium, calcium as well as several micronutrients. To explore the potential use of wood ash as a fertiliser, the growth enhancing properties of Sitka spruce (Picea sitchensis Bong.) wood ash were contrasted with the potential toxic action, using common duckweed (Lemna minor L.) as a model test species. The growth of L. minor exposed to wood bottom and fly ash solids and corresponding leachates was assessed in ultra-oligotrophic and eutrophic media. Ash solids and leachates were also tested as neutralized preparations. Suspended ash solids promoted L. minor growth up to concentrations of 2.5-5g/L. Leachates promoted growth up to 10g ash equivalents per litre, but for bottom ash only. Beneficial effects of wood ash were most pronounced on ultra-oligotrophic medium. However, on such nutrient-deficient medium severe inhibition of L. minor biomass and frond growth was observed at relatively low concentrations of fly ash (EC 50 =14g/L). On standard, eutrophic medium, higher concentrations of fly ash (EC 50 =21g/L), or neutralized fly ash (EC 50 =37g/L) were required to impede growth. Bottom ash, or neutralized bottom ash retarded growth at concentrations of 51g/L and 74g/L (EC 50 ), respectively, in eutrophic medium. It appears that phytotoxicity is due to the elemental composition of the ash, its alkaline character, and possible interactions between these two properties. Growth promotion was due to the substantial content of plant nutrients. This study underlines the importance of the receiving environment (nutrient status and pH) in determining the balance between toxicity and growth promotion, and shows that the margin between growth promoting and toxicity inducing concentrations can be enlarged through ash neutralization. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. The Effect of Communications Medium on the Fundamental Frequency of Speech.

    ERIC Educational Resources Information Center

    Noll, A. Michael

    1978-01-01

    Describes the results of preliminary experiments to investigate the effects of communications medium (face-to-face and two-way closed circuit television) on the fundamental frequency of speakers in a dyadic communications situation. (JMF)

  12. Antitumor Activity of Rat Mesenchymal Stem Cells during Direct or Indirect Co-Culturing with C6 Glioma Cells.

    PubMed

    Gabashvili, A N; Baklaushev, V P; Grinenko, N F; Mel'nikov, P A; Cherepanov, S A; Levinsky, A B; Chehonin, V P

    2016-02-01

    The tumor-suppressive effect of rat mesenchymal stem cells against low-differentiated rat C6 glioma cells during their direct and indirect co-culturing and during culturing of C6 glioma cells in the medium conditioned by mesenchymal stem cells was studied in an in vitro experiment. The most pronounced antitumor activity of mesenchymal stem cells was observed during direct co-culturing with C6 glioma cells. The number of live C6 glioma cells during indirect co-culturing and during culturing in conditioned medium was slightly higher than during direct co-culturing, but significantly differed from the control (C6 glioma cells cultured in medium conditioned by C6 glioma cells). The cytotoxic effect of medium conditioned by mesenchymal stem cells was not related to medium depletion by glioma cells during their growth. The medium conditioned by other "non-stem" cells (rat astrocytes and fibroblasts) produced no tumor-suppressive effect. Rat mesenchymal stem cells, similar to rat C6 glioma cells express connexin 43, the main astroglial gap junction protein. During co-culturing, mesenchymal stem cells and glioma C6 cells formed functionally active gap junctions. Gap junction blockade with connexon inhibitor carbenoxolone attenuated the antitumor effect observed during direct co-culturing of C6 glioma cells and mesenchymal stem cells to the level produced by conditioned medium. Cell-cell signaling mediated by gap junctions can be a mechanism of the tumor-suppressive effect of mesenchymal stem cells against C6 glioma cells. This phenomenon can be used for the development of new methods of cell therapy for high-grade malignant gliomas.

  13. Large Fizeau's light-dragging effect in a moving electromagnetically induced transparent medium.

    PubMed

    Kuan, Pei-Chen; Huang, Chang; Chan, Wei Sheng; Kosen, Sandoko; Lan, Shau-Yu

    2016-10-03

    As one of the most influential experiments on the development of modern macroscopic theory from Newtonian mechanics to Einstein's special theory of relativity, the phenomenon of light dragging in a moving medium has been discussed and observed extensively in different types of systems. To have a significant dragging effect, the long duration of light travelling in the medium is preferred. Here we demonstrate a light-dragging experiment in an electromagnetically induced transparent cold atomic ensemble and enhance the dragging effect by at least three orders of magnitude compared with the previous experiments. With a large enhancement of the dragging effect, we realize an atom-based velocimeter that has a sensitivity two orders of magnitude higher than the velocity width of the atomic medium used. Such a demonstration could pave the way for motional sensing using the collective state of atoms in a room temperature vapour cell or solid state material.

  14. Evaluation of the effects of a plasma activated medium on cancer cells

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

    Mohades, S.; Laroussi, M., E-mail: mlarouss@odu.edu; Sears, J.

    2015-12-15

    The interaction of low temperature plasma with liquids is a relevant topic of study to the field of plasma medicine. This is because cells and tissues are normally surrounded or covered by biological fluids. Therefore, the chemistry induced by the plasma in the aqueous state becomes crucial and usually dictates the biological outcomes. This process became even more important after the discovery that plasma activated media can be useful in killing various cancer cell lines. Here, we report on the measurements of concentrations of hydrogen peroxide, a species known to have strong biological effects, produced by application of plasma tomore » a minimum essential culture medium. The activated medium is then used to treat SCaBER cancer cells. Results indicate that the plasma activated medium can kill the cancer cells in a dose dependent manner, retain its killing effect for several hours, and is as effective as apoptosis inducing drugs.« less

  15. Decontamination Efficacy of Three Commercial-Off-The-Shelf (COTS) Sporicidal Disinfectants on Medium-Sized Panels Contaminated with Surrogate Spores of Bacillus anthracis

    PubMed Central

    Sabol, Jonathan P.

    2014-01-01

    In the event of a wide area release and contamination of a biological agent in an outdoor environment and to building exteriors, decontamination is likely to consume the Nation’s remediation capacity, requiring years to cleanup, and leading to incalculable economic losses. This is in part due to scant body of efficacy data on surface areas larger than those studied in a typical laboratory (5×10-cm), resulting in low confidence for operational considerations in sampling and quantitative measurements of prospective technologies recruited in effective cleanup and restoration response. In addition to well-documented fumigation-based cleanup efforts, agencies responsible for mitigation of contaminated sites are exploring alternative methods for decontamination including combinations of disposal of contaminated items, source reduction by vacuuming, mechanical scrubbing, and low-technology alternatives such as pH-adjusted bleach pressure wash. If proven effective, a pressure wash-based removal of Bacillus anthracis spores from building surfaces with readily available equipment will significantly increase the readiness of Federal agencies to meet the daunting challenge of restoration and cleanup effort following a wide-area biological release. In this inter-agency study, the efficacy of commercial-of-the-shelf sporicidal disinfectants applied using backpack sprayers was evaluated in decontamination of spores on the surfaces of medium-sized (∼1.2 m2) panels of steel, pressure-treated (PT) lumber, and brick veneer. Of the three disinfectants, pH-amended bleach, Peridox, and CASCAD evaluated; CASCAD was found to be the most effective in decontamination of spores from all three panel surface types. PMID:24940605

  16. Detecting and Identifying Organic Molecules in Space - The AstroBiology Explorer (ABE) MIDEX Mission Concept

    NASA Technical Reports Server (NTRS)

    Sandford, Scott A.

    2001-01-01

    Infrared spectroscopy in the 2.5-16 micron (4000-625/cm) range is a principle means by which organic compounds are detected and identified in space. Ground-based, airborne, and spaceborne IR spectral studies have already demonstrated that a significant fraction of the carbon in the interstellar medium (ISM) resides in the form of complex organic molecular species. Unfortunately, neither the distribution of these materials nor their genetic and evolutionary relationships with each other or their environments are well understood. The Astrobiology Explorer (ABE) is a MIDEX (Medium-class Explorer) mission concept currently under study at NASA's Ames Research Center in collaboration with Ball Aerospace and Technologies Corporation. ABE will conduct IR spectroscopic observations to address outstanding important problems in astrobiology, astrochemistry, and astrophysics. The core observational program would make fundamental scientific progress in understanding (1) the evolution of ices and organic matter in dense molecular clouds and young forming stellar systems, (2) the chemical evolution of organic molecules in the ISM as they transition from AGB outflows to planetary nebulae to the general diffuse ISM to H II regions and dense clouds, (3) the distribution of organics in the diffuse ISM, (4) the nature of organics in the Solar System (in comets, asteroids, satellites), and (5) the nature and distribution of organics in local galaxies. Both the scientific goals of the mission and how they would be achieved will be discussed.

  17. Detecting and Identifying Organic Molecules in Space: The AstroBiology Explorer (ABE) MIDEX Mission Concept

    NASA Technical Reports Server (NTRS)

    Sandford, Scott A.; DeVincenzi, Donald (Technical Monitor)

    2001-01-01

    Infrared spectroscopy in the 2.5-16 microns (4000-625/cm) range is a principle means by which organic compounds are detected and identified in space. Ground-based, airborne, and spaceborne IR spectral studies have already demonstrated that a significant fraction of the carbon in the interstellar medium (ISM) resides in the form of complex organic molecular species. Unfortunately, neither the distribution of these materials nor their genetic and evolutionary relationships with each other or their environments are well understood. The Astrobiology Explorer (ABE) is a MIDEX (Medium-class Explorer) mission concept currently under study at NASA's Ames Research Center in collaboration with Ball Aerospace and Technologies Corporation. ABE will conduct IR spectroscopic observations to address outstanding important problems in astrobiology, astrochemistry, and astrophysics. The core observational program would make fundamental scientific progress in understanding (1) the evolution of ices and organic matter in dense molecular clouds and young forming stellar systems, (2) the chemical evolution of organic molecules in the ISM as they transition from AGB outflows to planetary nebulae to the general diffuse ISM to H II regions and dense clouds, (3) the distribution of organics in the diffuse ISM, (4) the nature of organics in the Solar System (in comets, asteroids, satellites), and (5) the nature and distribution of organics in local galaxies. Both the scientific goals of the mission and how they would be achieved will be discussed.

  18. Medium effect on the characteristics of the coupled seismic and electromagnetic signals.

    PubMed

    Huang, Qinghua; Ren, Hengxin; Zhang, Dan; Chen, Y John

    2015-01-01

    Recently developed numerical simulation technique can simulate the coupled seismic and electromagnetic signals for a double couple point source or a finite fault planar source. Besides the source effect, the simulation results showed that both medium structure and medium property could affect the coupled seismic and electromagnetic signals. The waveform of coupled signals for a layered structure is more complicated than that for a simple uniform structure. Different from the seismic signals, the electromagnetic signals are sensitive to the medium properties such as fluid salinity and fluid viscosity. Therefore, the co-seismic electromagnetic signals may be more informative than seismic signals.

  19. Medium effect on the characteristics of the coupled seismic and electromagnetic signals

    PubMed Central

    HUANG, Qinghua; REN, Hengxin; ZHANG, Dan; CHEN, Y. John

    2015-01-01

    Recently developed numerical simulation technique can simulate the coupled seismic and electromagnetic signals for a double couple point source or a finite fault planar source. Besides the source effect, the simulation results showed that both medium structure and medium property could affect the coupled seismic and electromagnetic signals. The waveform of coupled signals for a layered structure is more complicated than that for a simple uniform structure. Different from the seismic signals, the electromagnetic signals are sensitive to the medium properties such as fluid salinity and fluid viscosity. Therefore, the co-seismic electromagnetic signals may be more informative than seismic signals. PMID:25743062

  20. Physical structure changes of solid medium by steam explosion sterilization.

    PubMed

    Zhao, Zhi-Min; Wang, Lan; Chen, Hong-Zhang

    2016-03-01

    Physical structure changes of solid medium were investigated to reveal effects of steam explosion sterilization on solid-state fermentation (SSF). Results indicated that steam explosion changed the structure of solid medium at both molecular and three-dimensional structural levels, which exposed hydrophilic groups and enlarged pores and cavities. It was interesting to find that pores where capillary water located were the active sites for SSF, due to the close relationship among capillary water relaxation time, specific surface area and fermentation performance. Therefore, steam explosion sterilization increased the effective contact area for microbial cells on solid medium, which contributed to improving SSF performance. Combined with the previous research, mechanisms of SSF improvement by steam explosion sterilization contained both chemical and physical effects. Copyright © 2015 Elsevier Ltd. All rights reserved.

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