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Sample records for key factors controlling

  1. Beyond microarrays: Finding key transcription factors controlling signal transduction pathways

    PubMed Central

    Kel, Alexdander; Voss, Nico; Jauregui, Ruy; Kel-Margoulis, Olga; Wingender, Edgar

    2006-01-01

    Background Massive gene expression changes in different cellular states measured by microarrays, in fact, reflect just an "echo" of real molecular processes in the cells. Transcription factors constitute a class of the regulatory molecules that typically require posttranscriptional modifications or ligand binding in order to exert their function. Therefore, such important functional changes of transcription factors are not directly visible in the microarray experiments. Results We developed a novel approach to find key transcription factors that may explain concerted expression changes of specific components of the signal transduction network. The approach aims at revealing evidence of positive feedback loops in the signal transduction circuits through activation of pathway-specific transcription factors. We demonstrate that promoters of genes encoding components of many known signal transduction pathways are enriched by binding sites of those transcription factors that are endpoints of the considered pathways. Application of the approach to the microarray gene expression data on TNF-alpha stimulated primary human endothelial cells helped to reveal novel key transcription factors potentially involved in the regulation of the signal transduction pathways of the cells. Conclusion We developed a novel computational approach for revealing key transcription factors by knowledge-based analysis of gene expression data with the help of databases on gene regulatory networks (TRANSFAC® and TRANSPATH®). The corresponding software and databases are available at . PMID:17118134

  2. Review of key factors controlling engineered nanoparticle transport in porous media.

    PubMed

    Wang, Mei; Gao, Bin; Tang, Deshan

    2016-11-15

    Nanotechnology, an emerging technology, has witnessed rapid development in production and application. Engineered nanomaterials revolutionize the industry due to their unique structure and superior performance. The release of engineered nanoparticles (ENPs) into the environment, however, may pose risks to the environment and public health. To advance current understanding of environmental behaviors of ENPs, this work provides an introductory overview of ENP fate and transport in porous media. It systematically reviews the key factors controlling their fate and transport in porous media. It first provides a brief overview of common ENPs in the environment and their sources. The key factors that govern ENP transport in porous media are then categorized into three groups: (1) nature of ENPs affecting their transport in porous media, (2) nature of porous media affecting ENP transport, and (3) nature of flow affecting ENP transport in porous media. In each group, findings in recent literature on the specific governing factors of ENP transport in porous media are discussed in details. Finally, this work concludes with remarks on the importance of ENP transport in porous media and directions for future research. PMID:27427890

  3. Key Factors Controlling the Applicability and Efficiency of Bioremediation of Chlorinated Ethenes In Situ

    NASA Astrophysics Data System (ADS)

    Zhang, M.; Yoshikawa, M.; Takeuchi, M.; Komai, T.

    2012-12-01

    Bioremediation has been considered as one of environmentally friendly and cost effective approaches for cleaning up the sites polluted by organic contaminants, such as chlorinated ethenes. Although bioremediation, in its widest sense, is not new, and many researches have been performed on bioremediation of different kinds of pollutants, an effective design and implication of in situ bioremediation still remains a challenging problem because of the complexity. Many factors may affect the applicability and efficiency of bioremediation of chlorinated ethenes in situ, which include the type and concentration of contaminants, biological, geological and hydro-geological conditions of the site, physical and chemical characteristics of groundwater and soils to be treated, as well as the constraints in engineering. In this presentation, an overview together with a detailed discussion on each factor will be provided. The influences of individual factors are discussed using the data obtained or cited from different sites and experiments, and thus under different environmental conditions. The results of this study illustrated that 1) the establishment of microbial consortium is of crucial importance for a complete degradation of chlorinated ethenes, 2) in situ control of favorable conditions for increasing microbial activities for bio-degradation through a designed pathway is the key to success, 3) the focus of a successful remediation system is to design an effective delivery process that is capable of producing adequate amendment mixing of contaminant-degrading bacteria, appropriate concentrations of electron acceptors, electron donors, and microbial nutrients in the subsurface treatment area.

  4. Key Factors Controlling Space- and Time-Linked Rare Earth Element Distribution in Shallow Groundwaters

    NASA Astrophysics Data System (ADS)

    Dia, A.; Gruau, G.; Olivie-Lauquet, G.; Henin, O.; Petitjean, P.; Le Coz-Bouhnik, M.

    2001-12-01

    comparison of the different catchments shows that the spatial variability of the REE signatures between the hillslope DOC-poor groundwaters and the wetland DOC-rich groundwaters has to be the same whatever may be the climatic and geologic context. These results assess the key roles played in the REE transfer to hydrosystems by (i) the occurrence of organic compounds, acting as a trace-element carrier phase and (ii) redox condition changes. Finally, we propose that topography could be the ultimate key factor, through its ability to control the water table depth and therefore the organic colloids enrichment when groundwaters are flowing into organic-rich soil horizons.

  5. The key sigma factor of transition phase, SigH, controls sporulation, metabolism, and virulence factor expression in Clostridium difficile.

    PubMed

    Saujet, Laure; Monot, Marc; Dupuy, Bruno; Soutourina, Olga; Martin-Verstraete, Isabelle

    2011-07-01

    Toxin synthesis in Clostridium difficile increases as cells enter into stationary phase. We first compared the expression profiles of strain 630E during exponential growth and at the onset of stationary phase and showed that genes involved in sporulation, cellular division, and motility, as well as carbon and amino acid metabolism, were differentially expressed under these conditions. We inactivated the sigH gene, which encodes an alternative sigma factor involved in the transition to post-exponential phase in Bacillus subtilis. Then, we compared the expression profiles of strain 630E and the sigH mutant after 10 h of growth. About 60% of the genes that were differentially expressed between exponential and stationary phases, including genes involved in motility, sporulation, and metabolism, were regulated by SigH, which thus appears to be a key regulator of the transition phase in C. difficile. SigH positively controls several genes required for sporulation. Accordingly, sigH inactivation results in an asporogeneous phenotype. The spo0A and CD2492 genes, encoding the master regulator of sporulation and one of its associated kinases, and the spoIIA operon were transcribed from a SigH-dependent promoter. The expression of tcdA and tcdB, encoding the toxins, and of tcdR, encoding the sigma factor required for toxin production, increased in a sigH mutant. Finally, SigH regulates the expression of genes encoding surface-associated proteins, such as the Cwp66 adhesin, the S-layer precursor, and the flagellum components. Among the 286 genes positively regulated by SigH, about 40 transcriptional units presenting a SigH consensus in their promoter regions are good candidates for direct SigH targets. PMID:21572003

  6. Factorizing RSA Keys

    NASA Astrophysics Data System (ADS)

    Blakey, Ed

    Factorization is notoriously difficult. Though the problem is not known to be NP-hard, neither efficient, algorithmic solution nor technologically practicable, quantum-computer solution has been found. This apparent complexity, which renders infeasible the factorization of sufficiently large values, makes secure the RSA cryptographic system.

  7. Distributions of key exposure factors controlling the uptake of xenobiotic chemicals in an estuarine food web

    SciTech Connect

    Iannuzzi, T.J.; Harrington, N.W.; Shear, N.M.; Curry, C.L.; Carlson-Lynch, H.; Henning, M.H.; Su, S.H.; Rabbe, D.E.

    1996-11-01

    A critical evaluation of literature on the behavior, physiology, and ecology of common estuarine organisms was conducted in an attempt to develop probabilistic distributions for those variables that influence the uptake of xenobiotic chemicals from sediments, water, and food sources. The ranges, central tendencies, and distributions of several key parameter values were identified for dominant organisms from various trophic levels, including the polychaete Nereis virens, mummichog (Fundulus heteroclitus), blue crab (Callinectes sapidus), and striped bass (Morone saxatilis). The exposure factors of interest included ingestion rate for various food sources, growth rate, respiration rate, excretion rate, body weight, wet/dry weight ratio, lipid content, chemical assimilation efficiency, and food assimilation efficiency. These exposure factors are critical to the execution of mechanistic food web models, which, when properly calibrated, can be used to estimate tissue concentrations of nonionic chemicals in aquatic organisms based on knowledge of the bioenergetics and feeding interactions within a food web and the sediment and water concentrations of chemicals. In this article the authors describe the use of distributions for various exposure factors in the context of a mechanistic bioaccumulation model that is amenable to probabilistic analyses for multiple organisms within a food web. A case study is provided which compares the estimated versus measured concentrations of five polychlorinated biphenyl (PCB) congeners in a representative food web from the tidal portion of the Passaic River, New Jersey, USA. The results suggest that the model is accurate within an order of magnitude or less in estimating the bioaccumulation of PCBs in this food web without calibration. The results of a model sensitivity analysis suggest that the input parameters which most influence the output of the model are both chemical and organism specific.

  8. Key factors controlling microbial community response after a fire: importance of severity and recurrence

    NASA Astrophysics Data System (ADS)

    Lombao, Alba; Barreiro, Ana; Martín, Ángela; Díaz-Raviña, Montserrat

    2015-04-01

    Microorganisms play an important role in forest ecosystems, especially after fire when vegetation is destroyed and soil is bared. Fire severity and recurrence might be one of main factors controlling the microbial response after a wildfire but information about this topic is scarce. The aim of this study is to evaluate the influence of fire regimen (recurrence and severity) on soil microbial community structure by means of the analysis of phospholipid fatty acid (PLFA). The study was performed with unburned and burned samples collected from the top layer of a soil affected by a high severity fire (Laza, NW Spain) heated under laboratory conditions at different temperatures (50°C, 75°C, 100°C, 125°C, 150°C, 175°C, 200°C, 300°C) to simulate different fire intensities; the process was repeated after further soil recovery (1 month incubation) to simulate fire recurrence. The soil temperature was measured with thermocouples and used to calculate the degree-hours as estimation of the amount of heat supplied to the samples (fire severity). The PLFA analysis was used to estimate total biomass and the biomass of specific groups (bacteria, fungi, gram-positive bacteria and gram-negative bacteria) as well as microbial community structure (PLFA pattern) and PLFA data were analyzed by means of principal component analysis (PCA) in order to identify main factors determining microbial community structure. The results of PCA, performed with the whole PLFA data set, showed that first component explained 35% of variation and clearly allow us to differentiate unburned samples from the corresponding burned samples, while the second component, explaining 16% of variation, separated samples according the heating temperature. A marked impact of fire regimen on soil microorganisms was detected; the microbial community response varied depending on previous history of soil heating and the magnitude of changes in the PLFA pattern was related to the amount of heat supplied to the

  9. Mechanisms of surgical control of type 2 diabetes: GLP-1 is the key factor-Maybe.

    PubMed

    Salehi, Marzieh; D'Alessio, David A

    2016-07-01

    Bariatric surgery is the most effective treatment for obesity and diabetes. The 2 most commonly performed weight-loss procedures, Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy, improve glycemic control in patients with type 2 diabetes independent of weight loss. One of the early hypotheses raised to explain the immediate antidiabetic effect of RYGB was that rapid delivery of nutrients from the stomach pouch into the distal small intestine enhances enteroinsular signaling to promote insulin signaling. Given the tenfold increase in postmeal glucagon-like peptide-1 (GLP-1) response compared to unchanged integrated levels of postprandial glucose-dependent insulinotropic peptide after RYGB, enhanced meal-induced insulin secretion after this procedure was thought to be the result of elevated glucose and GLP-1 levels. In this contribution to the larger point-counterpoint debate about the role of GLP-1 after bariatric surgery, most of the focus will be on RYGB. PMID:27568473

  10. Key factors help programs succeed.

    PubMed

    Finger, W R

    1997-01-01

    The World Health Organization is coordinating a review (with the United Nations Population Fund and UNICEF) of key interventions designed to improve adolescent health services, focusing on the effectiveness of these efforts. Making services more available involves the attitude and training of providers, the logistics of clinic location and service, and the questions of privacy and confidentiality. Successful programs identify specific target groups defined by age, school status, marital status, and other social factors. In a recent evaluation of 70 projects focusing on adolescents, UNFPA found that almost none of them defined their target populations clearly. Marital status is particularly important, for the unmarried often face more obstacles to services. Providers should involve youth in planning and implementing reproductive health services and evaluating programs by working with youth focus groups and workshops. A review of the Family Health International's AIDS Control and Prevention (AIDSCAP) Project of 21 peer education projects in Africa, Asia, and Latin America showed that peer education is useful for providing HIV/AIDS information. In successful peer programming selection and training, skills building, effective provision of information and referrals, and minimal turnover are key elements. Involving community leaders, parents, teachers helps achieve the balance of needs and culture and traditions. A UNFPA analysis found that most projects did not involve parents and community groups. Sex education programs were particularly divisive. The accessibility of services depends on convenience of location, clinic hours, confidentiality, and style of services. The basic evaluation tool is simple observation. In 1992 an AIDS prevention project in Kenya used an outcome evaluation with interviews and found that the target audience had more positive behavior change. Sustaining good programs should also be included in the planning phase, as was done by the CORA project

  11. Dynamic C and N stocks - key factors controlling the C gas exchange of maize in a heterogenous peatland

    NASA Astrophysics Data System (ADS)

    Pohl, M.; Hoffmann, M.; Hagemann, U.; Giebels, M.; Albiac Borraz, E.; Sommer, M.; Augustin, J.

    2014-11-01

    Drainage and cultivation of fen peatlands creates complex small-scale mosaics of soils with extremely variable soil organic carbon (SOC) stocks and groundwater-level (GWL). To date, it remains unclear if such sites are sources or sinks for greenhouse gases like CO2 and CH4, especially if used for cropland. As individual control factors like GWL fail to account for this complexity, holistic approaches combining gas fluxes with the underlying processes are required to understand the carbon (C) gas exchange of drained fens. It can be assumed that the stocks of SOC and N located above the variable GWL - defined as dynamic C and N stocks - play a key role in the regulation of plant- and microbially mediated C gas fluxes of these soils. To test this assumption, the present study analysed the C gas exchange (gross primary production - GPP, ecosystem respiration - Reco, net ecosystem exchange - NEE, CH4) of maize using manual chambers for four years. The study sites were located near Paulinenaue, Germany. Here we selected three soils, which represent the full gradient in pedogenesis, GWL and SOC stocks (0-1 m) of the fen peatland: (a) Haplic Arenosol (AR; 8 kg C m-2); (b) Mollic Gleysol (GL; 38 kg C m-2); and (c) Hemic Histosol (HS; 87 kg C m-2). Daily GWL data was used to calculate dynamic SOC (SOCdyn) and N (Ndyn) stocks. Average annual NEE differed considerably among sites, ranging from 47 ± 30 g C m-2 a-1 at AR to -305 ± 123 g C m-2 a-1 at GL and -127 ± 212 g C m-2 a-1 at HS. While static SOC and N stocks showed no significant effect on C fluxes, SOCdyn and Ndyn and their interaction with GWL strongly influenced the C gas exchange, particularly NEE and the GPP:Reco ratio. Moreover, based on nonlinear regression analysis, 86% of NEE variability was explained by GWL and SOCdyn. The observed high relevance of dynamic SOC and N stocks in the aerobic zone for plant and soil gas exchange likely originates from the effects of GWL-dependent N availability on C formation and

  12. Dynamic C and N stocks - key factors controlling the C gas exchange of maize in heterogenous peatland

    NASA Astrophysics Data System (ADS)

    Pohl, M.; Hoffmann, M.; Hagemann, U.; Giebels, M.; Albiac Borraz, E.; Sommer, M.; Augustin, J.

    2015-05-01

    The drainage and cultivation of fen peatlands create complex small-scale mosaics of soils with extremely variable soil organic carbon (SOC) stocks and groundwater levels (GWLs). To date, the significance of such sites as sources or sinks for greenhouse gases such as CO2 and CH4 is still unclear, especially if the sites are used for cropland. As individual control factors such as GWL fail to account for this complexity, holistic approaches combining gas fluxes with the underlying processes are required to understand the carbon (C) gas exchange of drained fens. It can be assumed that the stocks of SOC and N located above the variable GWL - defined as dynamic C and N stocks - play a key role in the regulation of the plant- and microbially mediated CO2 fluxes in these soils and, inversely, for CH4. To test this assumption, the present study analysed the C gas exchange (gross primary production - GPP; ecosystem respiration - Reco; net ecosystem exchange - NEE; CH4) of maize using manual chambers for 4 years. The study sites were located near Paulinenaue, Germany, where we selected three soil types representing the full gradient of GWL and SOC stocks (0-1 m) of the landscape: (a) Haplic Arenosol (AR; 8 kg C m-2); (b) Mollic Gleysol (GL; 38 kg C m-2); and (c) Hemic Histosol (HS; 87 kg C m-2). Daily GWL data were used to calculate dynamic SOC (SOCdyn) and N (Ndyn) stocks. Average annual NEE differed considerably among sites, ranging from 47 ± 30 g C m-2 yr-1 in AR to -305 ± 123 g C m-2 yr-1 in GL and -127 ± 212 g C m-2 yr-1 in HS. While static SOC and N stocks showed no significant effect on C fluxes, SOCdyn and Ndyn and their interaction with GWL strongly influenced the C gas exchange, particularly NEE and the GPP : Reco ratio. Moreover, based on nonlinear regression analysis, 86% of NEE variability was explained by GWL and SOCdyn. The observed high relevance of dynamic SOC and N stocks in the aerobic zone for plant and soil gas exchange likely originates from the

  13. The Key Sigma Factor of Transition Phase, SigH, Controls Sporulation, Metabolism, and Virulence Factor Expression in Clostridium difficile▿†

    PubMed Central

    Saujet, Laure; Monot, Marc; Dupuy, Bruno; Soutourina, Olga; Martin-Verstraete, Isabelle

    2011-01-01

    Toxin synthesis in Clostridium difficile increases as cells enter into stationary phase. We first compared the expression profiles of strain 630E during exponential growth and at the onset of stationary phase and showed that genes involved in sporulation, cellular division, and motility, as well as carbon and amino acid metabolism, were differentially expressed under these conditions. We inactivated the sigH gene, which encodes an alternative sigma factor involved in the transition to post-exponential phase in Bacillus subtilis. Then, we compared the expression profiles of strain 630E and the sigH mutant after 10 h of growth. About 60% of the genes that were differentially expressed between exponential and stationary phases, including genes involved in motility, sporulation, and metabolism, were regulated by SigH, which thus appears to be a key regulator of the transition phase in C. difficile. SigH positively controls several genes required for sporulation. Accordingly, sigH inactivation results in an asporogeneous phenotype. The spo0A and CD2492 genes, encoding the master regulator of sporulation and one of its associated kinases, and the spoIIA operon were transcribed from a SigH-dependent promoter. The expression of tcdA and tcdB, encoding the toxins, and of tcdR, encoding the sigma factor required for toxin production, increased in a sigH mutant. Finally, SigH regulates the expression of genes encoding surface-associated proteins, such as the Cwp66 adhesin, the S-layer precursor, and the flagellum components. Among the 286 genes positively regulated by SigH, about 40 transcriptional units presenting a SigH consensus in their promoter regions are good candidates for direct SigH targets. PMID:21572003

  14. Key Factors Controlling the Growth of Biological Soil Crusts: Towards a Protocol to Produce Biocrusts in Greenhouse Facilities

    NASA Astrophysics Data System (ADS)

    Velasco Ayuso, Sergio; María Giraldo Silva, Ana; Nelson, Corey; Barger, Nichole; Antoninka, Anita; Bowker, Matthew; Garcia-Pichel, Ferran

    2016-04-01

    Biological soil crusts (= biocrusts) are topsoil communities comprise of, but not limited to, cyanobacteria, algae, lichens, and mosses that grow intimately associated with soil particles in drylands. Biocrusts have central ecological roles in these areas as sources of carbon and nutrients, and efficiently retain water and prevent soil erosion, which improves soil structure and promotes soil fertility. However, human activities, such as cattle grazing, hiking or military training, are rapidly striking biocrusts. Although it is well known that the inoculation with cyanobacteria or lichens can enhance the recovery of biocrusts in degraded soils, little is known about the factors that control their growth rates. Using soil and inocula from four different sites located in one cold desert (Utah) and in one hot desert (New Mexico), we performed a fractional factorial experiment involving seven factors (water, light, P, N, calcium carbonate, trace metals and type of inoculum) to screen their effects on the growth of biocrusts. After four months, we measured the concentration of chlorophyll a, and we discovered that water, light and P, N or P+N were the most important factors controlling the growth of biocrusts. In the experimental treatments involving these three factors we measured a similar concentration of chlorophyll a (or even higher) to this found in the field locations. Amplification of the 16S rRNA gene segment using universal bacteria primers revealed a microbial community composition in the biocrusts grown that closely corresponds to initial measurements made on inocula. In summary, based on our success in obtaining biocrust biomass from natural communities in greenhouse facilities, without significantly changing its community composition at the phylum and cyanobacterial level, we are paving the road to propose a protocol to produce a high quality-nursed inoculum aiming to assist restoration of arid and semi-arid ecosystems affected by large-scale disturbances.

  15. Hyaluronic acid regulates a key redox control factor Nrf2 via phosphorylation of Akt in bovine articular chondrocytes

    PubMed Central

    Onodera, Yuta; Teramura, Takeshi; Takehara, Toshiyuki; Fukuda, Kanji

    2015-01-01

    One important pharmacological function of hyaluronic acid (HA) in chondrocytes is reduction of cellular superoxide generation and accumulation. Here we demonstrated a relationship between HA supplementation and accumulation of Nuclear factor-erythroid-2-related factor 2 (Nrf2), which is a master transcription factor in cellular redox reactions, in cultured chondrocytes derived from bovine joint cartilage. In HA-treated chondrocytes, expression of Nrf2 and its downstream genes was upregulated. In HA-treated chondrocytes, Akt was phosphorylated, and inhibition of Akt activity or suppression of HA receptors CD44 and/or RHAMM with siRNAs prevented HA-mediated Nrf2 accumulation. Furthermore, Nrf2 siRNA inhibited the HA effect on antioxidant enzymes. These results show that HA might contribute to ROS reduction through Nrf2 regulation by activating Akt. Our study suggests a new mechanism for extracellular matrix (ECM)-mediated redox systems in chondrocytes. PMID:26106522

  16. Controlling Shear Stress in 3D Bioprinting is a Key Factor to Balance Printing Resolution and Stem Cell Integrity.

    PubMed

    Blaeser, Andreas; Duarte Campos, Daniela Filipa; Puster, Uta; Richtering, Walter; Stevens, Molly M; Fischer, Horst

    2016-02-01

    A microvalve-based bioprinting system for the manufacturing of high-resolution, multimaterial 3D-structures is reported. Applying a straightforward fluid-dynamics model, the shear stress at the nozzle site can precisely be controlled. Using this system, a broad study on how cell viability and proliferation potential are affected by different levels of shear stress is conducted. Complex, multimaterial 3D structures are printed with high resolution. This work pioneers the investigation of shear stress-induced cell damage in 3D bioprinting and might help to comprehend and improve the outcome of cell-printing studies in the future. PMID:26626828

  17. Towards an effective control programme of soil-transmitted helminth infections among Orang Asli in rural Malaysia. Part 1: Prevalence and associated key factors

    PubMed Central

    2013-01-01

    Background Despite the continuous efforts to improve the quality of life of Orang Asli (Aborigines) communities, these communities are still plagued with a wide range of health problems including parasitic infections. The first part of this study aimed at determining the prevalence of soil-transmitted helminth (STH) infections and identifying their associated factors among rural Orang Asli children. Methods A cross-sectional study was carried out among 484 Orang Asli children aged ≤ 15 years (235 females and 249 males) belonging to 215 households from 13 villages in Lipis district, Pahang, Malaysia. Faecal samples were collected and examined by using formalin-ether sedimentation, Kato Katz and Harada Mori techniques. Demographic, socioeconomic, environmental and behavioural information were collected by using a pre-tested questionnaire. Results Overall, 78.1% of the children were found to be infected with one or more STH species. The prevalence of trichuriasis, ascariasis and hookworm infections were 71.7%, 37.4% and 17.6%, respectively. Almost all, three quarters and one fifth of trichuriasis, ascariasis and hookworm infections, respectively, were of moderate-to-heavy intensities. Multiple logistic regression analysis showed that age of ≥ 6 years (school-age), using unsafe water supply as a source for drinking water, absence of a toilet in the house, large family size (≥ 7 members), not washing hands before eating, and not washing hands after defecation were the key factors significantly associated with STH among these children. Conclusion This study reveals an alarmingly high prevalence of STH among Orang Asli children and clearly brings out an urgent need to implement school-based de-worming programmes and other control measures like providing a proper sanitation, as well as a treated drinking water supply and proper health education regarding good personal hygiene practices. Such an integrated control program will help significantly in

  18. Evolving Systems and Adaptive Key Component Control

    NASA Technical Reports Server (NTRS)

    Frost, Susan A.; Balas, Mark J.

    2009-01-01

    We propose a new framework called Evolving Systems to describe the self-assembly, or autonomous assembly, of actively controlled dynamical subsystems into an Evolved System with a higher purpose. An introduction to Evolving Systems and exploration of the essential topics of the control and stability properties of Evolving Systems is provided. This chapter defines a framework for Evolving Systems, develops theory and control solutions for fundamental characteristics of Evolving Systems, and provides illustrative examples of Evolving Systems and their control with adaptive key component controllers.

  19. Helicopter training simulators: Key market factors

    NASA Technical Reports Server (NTRS)

    Mcintosh, John

    1992-01-01

    Simulators will gain an increasingly important role in training helicopter pilots only if the simulators are of sufficient fidelity to provide positive transfer of skills to the aircraft. This must be done within an economic model of return on investment. Although rotor pilot demand is still only a small percentage of overall pilot requirements, it will grow in significance. This presentation described the salient factors influencing the use of helicopter training simulators.

  20. Key Factors of Circulation System Analysis and Design

    ERIC Educational Resources Information Center

    McGee, Rob

    1972-01-01

    Explained are basic concepts and components that are common to manual, machine-aided, and computer-based systems, and their significance as key factors in the analysis and design of academic library circulation systems is documented. (2 references) (Author)

  1. Zur (FurB) is a key factor in the control of the oxidative stress response in Anabaena sp. PCC 7120.

    PubMed

    Sein-Echaluce, Violeta C; González, Andrés; Napolitano, Mauro; Luque, Ignacio; Barja, Francisco; Peleato, M Luisa; Fillat, María F

    2015-06-01

    Iron and zinc are necessary nutrients whose homeostasis is tightly controlled by members of the ferric uptake regulator (FUR) superfamily in the cyanobacterium Anabaena sp. PCC7120. Although the link between iron metabolism and oxidative stress management is well documented, little is known about the connection between zinc homeostasis and the oxidative stress response in cyanobacteria. Zinc homeostasis in Anabaena is controlled by Zur, also named FurB. When overexpressed in Escherichia coli, Zur (FurB) improved cell survival during oxidative stress. In order to investigate the possible correlation between Zur and the oxidative stress response in Anabaena, zur deletion and zur-overexpressing strains have been constructed, and the consequences of Zur imbalance evaluated. The lack of Zur increased sensitivity to hydrogen peroxide (H2 O2 ), whereas an excess of Zur enhanced oxidative stress resistance. Both mutants displayed pleiotropic phenotypes, including alterations on the filament surfaces observable by scanning electron microscopy, reduced content of endogenous H2 O2 and altered expression of sodA, catalases and several peroxiredoxins. Transcriptional and biochemical analyses unveiled that the appropriate level of Zur is required for proper control of the oxidative stress response and allowed us to identify major antioxidant enzymes as novel members of the Zur regulon. PMID:25244409

  2. The key role of socio-demographic and socio-environmental factors in urban malaria occurrence and control - An illustration using the city of Yaoundé.

    PubMed

    Ngom, Roland; Siegmund, Alexander

    2015-05-01

    Cities in developing countries are experiencing an unprecedented population growth that illustrates a demographic transition and a shift towards modernization with consequences on their epidemiological profiles. However, this change is characterized by an important rural-to-urban social and cultural transfer that can bias the expected epidemiological transition; at the same time, this transfer renders the understanding of the occurrence of communicable diseases more complex than it appears. Urban malaria occurrence was modeled for the city of Yaoundé in Cameroon. Retrospective interviews were conducted to describe a variety of epidemiological, social and environmental variables at the household level. Various ecological variables originating from remote sensing data were also integrated. Multivariate multilevel negative binomial analyses were developed to evaluate the distinct contributions of explanatory social and ecological variables. Spatial models based on the level of urbanity were implemented to understand the intelligence of urban malaria as characterized by those variables. The results showed an overall higher statistical importance of socio-environmental variables, particularly those describing rural origin socio-cultural features in terms of non-conventional housing types and urban agriculture (UA). The spatial patterns of the urban malaria occurrences displayed a complex combination of population density gradients and socio-environmental factors, illustrating the importance of conventional urban features over rural/non-conventional features in reducing the occurrence of urban malaria. PMID:25498155

  3. Key systemic and environmental risk factors for implant failure.

    PubMed

    Dawson, Dolphus R; Jasper, Samuel

    2015-01-01

    Dental implants are an important treatment option for patients interested in replacing lost or missing teeth. Although a robust body of literature has reviewed risk factors for tooth loss, the evidence for risk factors associated with dental implants is less well defined. This article focuses on key systemic risk factors relating to dental implant failure, as well as on perimucositis and peri-implantitis. PMID:25434557

  4. Power Factor Controller Study.

    SciTech Connect

    Knudson Engineers, Inc.

    1989-08-01

    The complete report is divided into three parts as follows: (1) This report combines a historical perspective with a current assessment of the use of power factor controllers for three-phase ac motor energy savings. The power factor controller (PFC) is a power electronics device that reduces voltage to a motor during periods of reduced motor torque requirements. (2) A power factor controller (PFC) is a power electronics device that reduces voltage to a motor during periods of reduced motor torque requirements. This report is the DEMONSTRATION phase of the PFC study. The phase report consists of three task reports -- Site Selection, Demonstration Preparation, and Demonstration. The reports explain how three sites were selected for demonstration, describe what was measured at each site and the method of measurement, and compare measured energy savings with calculated predictions of energy savings. The report concludes that PFCs can save energy on carefully selected motor applications. (3) The results of the demonstration task are described in this report. A power factor controller (PFC) is a power electronics device that reduces voltage to a motor during periods of reduced motor torque requirements. The demonstration phase of this study calculates projected energy savings with the use of a PFC and compares measured performance with the calculations. The effect of the PFC on motor power requirements, power factor and energy consumption shall be measured.

  5. Mitigation of Control Channel Jamming via Combinatorial Key Distribution

    NASA Astrophysics Data System (ADS)

    Falahati, Abolfazl; Azarafrooz, Mahdi

    The problem of countering control channel jamming against internal adversaries in wireless ad hoc networks is addressed. Using combinatorial key distribution, a new method to secure the control channel access is introduced. This method, utilizes the established keys in the key establishment phase to hide the location of control channels without the need for a secure BS. This is in obtained by combination of a collision free one-way function and a combinatorial key establishment method. The proposed scheme can be considered as a special case of the ALOHA random access schemes which uses the common established keys as its seeds to generate the pattern of transmission.

  6. Graduate Entrepreneurship Incubation Environments: A Framework of Key Success Factors

    ERIC Educational Resources Information Center

    Al-Dajani, Haya; Dedoussis, Evangelos; Watson, Erika; Tzokas, Nikalaos

    2014-01-01

    The benchmarking framework developed in this study is specifically designed for higher education institutions to consider when developing environments to encourage entrepreneurship among their students, graduates and staff. The objective of the study was to identify key success factors of Graduate Entrepreneurship Incubator Environments (GEIEs)…

  7. Key Factors that Influence Recruiting Young Chinese Students

    ERIC Educational Resources Information Center

    Wang, Zhenmin

    2007-01-01

    The discussion in this paper is based on the assumption that international education is equated to recruiting and educating international students, even though its true concept goes far beyond this narrow understanding. The purpose of this research is to look at the key factors that influence recruiting young Chinese students, and make sure all…

  8. Power Factor Controller

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Frank Nola invented the Power Factor Controller (PFC) at Marshall Space Flight Center more than a decade ago. Nola came up with a way to curb power wastage in AC induction motors. The PFC matches voltage with the motor's actual need by continuously sensing shifts between voltage and current. When it senses a light load it cuts the voltage to the minimum needed. Potential energy savings range from 8 to 65 percent.

  9. Partially Key Distribution with Public Key Cryptosystem Based on Error Control Codes

    NASA Astrophysics Data System (ADS)

    Tavallaei, Saeed Ebadi; Falahati, Abolfazl

    Due to the low level of security in public key cryptosystems based on number theory, fundamental difficulties such as "key escrow" in Public Key Infrastructure (PKI) and a secure channel in ID-based cryptography, a new key distribution cryptosystem based on Error Control Codes (ECC) is proposed . This idea is done by some modification on McEliece cryptosystem. The security of ECC cryptosystem obtains from the NP-Completeness of block codes decoding. The capability of generating public keys with variable lengths which is suitable for different applications will be provided by using ECC. It seems that usage of these cryptosystems because of decreasing in the security of cryptosystems based on number theory and increasing the lengths of their keys would be unavoidable in future.

  10. Faculty perceptions of key factors in interprofessional education.

    PubMed

    Loversidge, Jacqueline; Demb, Ada

    2015-01-01

    Embedding interprofessional education (IPE) into academic programs presents structural, curricular and human factor challenges. Nurses and physicians comprise the dominant dyad in healthcare, and therefore nursing and medical faculty are key in guiding future IPE approaches. However, faculty experiences with IPE are rarely reported. This paper presents perceptions of medical and nursing faculty about key factors related to IPE for pre-licensure medical and nursing students. Semi-structured interviews with 32 faculty from three Midwest universities were analyzed thematically in this phenomenological study based on collaboration and cooperation theories. Findings clustered into six categories. Specific subthemes little discussed in the literature are addressed in detail. Study participants felt the most powerful interprofessional student experiences were authentic and faculty-facilitated, that constructive clinical environments were crucial, that curriculum design challenges included disparities between undergraduate and graduate education, and that leadership commitment to full-time and adjunct faculty engagement and development was imperative. PMID:25495176

  11. Five key factors determining pairwise correlations in visual cortex

    PubMed Central

    Sahani, Maneesh; Carandini, Matteo

    2015-01-01

    The responses of cortical neurons to repeated presentation of a stimulus are highly variable, yet correlated. These “noise correlations” reflect a low-dimensional structure of population dynamics. Here, we examine noise correlations in 22,705 pairs of neurons in primary visual cortex (V1) of anesthetized cats, during ongoing activity and in response to artificial and natural visual stimuli. We measured how noise correlations depend on 11 factors. Because these factors are themselves not independent, we distinguished their influences using a nonlinear additive model. The model revealed that five key factors play a predominant role in determining pairwise correlations. Two of these are distance in cortex and difference in sensory tuning: these are known to decrease correlation. A third factor is firing rate: confirming most earlier observations, it markedly increased pairwise correlations. A fourth factor is spike width: cells with a broad spike were more strongly correlated amongst each other. A fifth factor is spike isolation: neurons with worse isolation were more correlated, even if they were recorded on different electrodes. For pairs of neurons with poor isolation, this last factor was the main determinant of correlations. These results were generally independent of stimulus type and timescale of analysis, but there were exceptions. For instance, pairwise correlations depended on difference in orientation tuning more during responses to gratings than to natural stimuli. These results consolidate disjoint observations in a vast literature on pairwise correlations and point towards regularities of population coding in sensory cortex. PMID:26019310

  12. Identifying Key Hospital Service Quality Factors in Online Health Communities

    PubMed Central

    Jung, Yuchul; Hur, Cinyoung; Jung, Dain

    2015-01-01

    Background The volume of health-related user-created content, especially hospital-related questions and answers in online health communities, has rapidly increased. Patients and caregivers participate in online community activities to share their experiences, exchange information, and ask about recommended or discredited hospitals. However, there is little research on how to identify hospital service quality automatically from the online communities. In the past, in-depth analysis of hospitals has used random sampling surveys. However, such surveys are becoming impractical owing to the rapidly increasing volume of online data and the diverse analysis requirements of related stakeholders. Objective As a solution for utilizing large-scale health-related information, we propose a novel approach to identify hospital service quality factors and overtime trends automatically from online health communities, especially hospital-related questions and answers. Methods We defined social media–based key quality factors for hospitals. In addition, we developed text mining techniques to detect such factors that frequently occur in online health communities. After detecting these factors that represent qualitative aspects of hospitals, we applied a sentiment analysis to recognize the types of recommendations in messages posted within online health communities. Korea’s two biggest online portals were used to test the effectiveness of detection of social media–based key quality factors for hospitals. Results To evaluate the proposed text mining techniques, we performed manual evaluations on the extraction and classification results, such as hospital name, service quality factors, and recommendation types using a random sample of messages (ie, 5.44% (9450/173,748) of the total messages). Service quality factor detection and hospital name extraction achieved average F1 scores of 91% and 78%, respectively. In terms of recommendation classification, performance (ie, precision) is

  13. Dietary Mineral Could Be One Key to Blood Pressure Control

    MedlinePlus

    ... https://medlineplus.gov/news/fullstory_159836.html Dietary Mineral Could Be One Key to Blood Pressure Control ... 2016 (HealthDay News) -- Sufficient dietary levels of the mineral nutrient magnesium might be a boon to good ...

  14. Key factors of successful JIT integration with IBS - An overview

    NASA Astrophysics Data System (ADS)

    Asri, Mohammad Azwanie Naim Mohammad; Nawi, Mohd Nasrun Mohd; Nadarajan, Santhirasegaran

    2016-08-01

    The Just-In-Time (JIT) philosophy has been used for many decades to increase productivity through waste elimination process. The purpose of this paper is to contribute to the knowledge by addressing the transportation and material delivery activities in Industrialized Building System (IBS) and integrating JIT to improve the performance of those activities. The literature review has been conducted through relevant database. It was found that there is a need for more holistic approach to be adopted to integrate JIT in IBS project. This paper discusses the key success factors for effective integration between JIT and IBS in the context of transportation and material delivery activities.

  15. Controlled order rearrangement encryption for quantum key distribution

    SciTech Connect

    Deng Fuguo; Long, G.L.

    2003-10-01

    A technique is devised to perform orthogonal state quantum key distribution. In this scheme, entangled parts of a quantum information carrier are sent from Alice to Bob through two quantum channels. However, before the transmission, the order of the quantum information carrier in one channel is reordered so that Eve cannot steal useful information. At the receiver's end, the order of the quantum information carrier is restored. The order rearrangement operation in both parties is controlled by a prior shared control key which is used repeatedly in a quantum key distribution session.

  16. Myopic Loss Aversion: Demystifying the Key Factors Influencing Decision Problem Framing

    ERIC Educational Resources Information Center

    Hardin, Andrew M.; Looney, Clayton Arlen

    2012-01-01

    Advancement of myopic loss aversion theory has been hamstrung by conflicting results, methodological inconsistencies, and a piecemeal approach toward understanding the key factors influencing decision problem framing. A series of controlled experiments provides a more holistic view of the variables promoting myopia. Extending the information…

  17. Key Response Planning Factors for the Aftermath of Nuclear Terrorism

    SciTech Connect

    Buddemeier, B R; Dillon, M B

    2009-01-21

    Despite hundreds of above-ground nuclear tests and data gathered from Hiroshima and Nagasaki, the effects of a ground-level, low-yield nuclear detonation in a modern urban environment are still the subject of considerable scientific debate. Extensive review of nuclear weapon effects studies and discussions with nuclear weapon effects experts from various federal agencies, national laboratories, and technical organizations have identified key issues and bounded some of the unknowns required to support response planning for a low-yield, ground-level nuclear detonation in a modern U.S. city. This study, which is focused primarily upon the hazards posed by radioactive fallout, used detailed fallout predictions from the advanced suite of three-dimensional (3-D) meteorology and plume/fallout models developed at Lawrence Livermore National Laboratory (LLNL), including extensive global Key Response Planning Factors for the Aftermath of Nuclear Terrorism geographical and real-time meteorological databases to support model calculations. This 3-D modeling system provides detailed simulations that account for complex meteorology and terrain effects. The results of initial modeling and analysis were presented to federal, state, and local working groups to obtain critical, broad-based review and feedback on strategy and messaging. This effort involved a diverse set of communities, including New York City, National Capitol Regions, Charlotte, Houston, Portland, and Los Angeles. The largest potential for reducing casualties during the post-detonation response phase comes from reducing exposure to fallout radiation. This can be accomplished through early, adequate sheltering followed by informed, delayed evacuation.B The response challenges to a nuclear detonation must be solved through multiple approaches of public education, planning, and rapid response actions. Because the successful response will require extensive coordination of a large number of organizations, supplemented by

  18. Control of key pecan insect pests using biorational pesticides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Key pecan insect pests include the pecan weevil, Curculio caryae, black pecan aphid, Melanocallis caryaefoliae, and stink bugs. Alternative control tactics are needed for management of these pests in organic and conventional systems. Our objective was to evaluate the potential utility of several a...

  19. Determination of specificity influencing residues for key transcription factor families

    PubMed Central

    Patel, Ronak Y.; Garde, Christian; D.Stormo, Gary

    2015-01-01

    Transcription factors (TFs) are major modulators of transcription and subsequent cellular processes. The binding of TFs to specific regulatory elements is governed by their specificity. Considering the gap between known TFs sequence and specificity, specificity prediction frameworks are highly desired. Key inputs to such frameworks are protein residues that modulate the specificity of TF under consideration. Simple measures like mutual information (MI) to delineate specificity influencing residues (SIRs) from alignment fail due to structural constraints imposed by the three-dimensional structure of protein. Structural restraints on the evolution of the amino-acid sequence lead to identification of false SIRs. In this manuscript we extended three methods (Direct Information, PSICOV and adjusted mutual information) that have been used to disentangle spurious indirect protein residue-residue contacts from direct contacts, to identify SIRs from joint alignments of amino-acids and specificity. We predicted SIRs forhomeodomain (HD), helix-loop-helix, LacI and GntR families of TFs using these methods and compared to MI. Using various measures, we show that the performance of these three methods is comparable but better than MI. Implication of these methods in specificity prediction framework is discussed. The methods are implemented as an R package and available along with the alignments at stormo.wustl.edu/SpecPred. PMID:26753103

  20. Key factors affecting urban runoff pollution under cold climatic conditions

    NASA Astrophysics Data System (ADS)

    Valtanen, Marjo; Sillanpää, Nora; Setälä, Heikki

    2015-10-01

    Urban runoff contains various pollutants and has the potential of deteriorating the quality of aquatic ecosystems. In this study our objective is to shed light on the factors that control the runoff water quality in urbanized catchments. The effects of runoff event characteristics, land use type and catchment imperviousness on event mass loads (EML) and event mean concentrations (EMC) were studied during warm and cold periods in three study catchments (6.1, 6.5 and 12.6 ha in size) in the city of Lahti, Finland. Runoff and rainfall were measured continuously for two years at each catchment. Runoff samples were taken for total nutrients (tot-P and tot-N), total suspended solids (TSS), heavy metals (Zn, Cr, Al, Co, Ni, Cu, Pb, Mn) and total organic carbon (TOC). Stepwise multiple linear regression analysis (SMLR) was used to identify general relationships between the following variables: event water quality, runoff event characteristics and catchment characteristics. In general, the studied variables explained 50-90% of the EMLs but only 30-60% of the EMCs, with runoff duration having an important role in most of the SMLR models. Mean runoff intensity or peak flow was also often included in the runoff quality models. Yet, the importance (being the first, second or third best) and role (negative or positive impact) of the explanatory variables varied between the cold and warm period. Land use type often explained cold period concentrations, but imperviousness alone explained EMCs weakly. As for EMLs, the influence of imperviousness and/or land use was season and pollutant dependent. The study suggests that pollutant loads can be - throughout the year - adequately predicted by runoff characteristics given that seasonal differences are taken into account. Although pollutant concentrations were sensitive to variation in seasonal and catchment conditions as well, the accurate estimation of EMCs would require a more complete set of explanatory factors than used in this

  1. Walking along the Fibroblast Growth Factor 10 Route: A Key Pathway to Understand the Control and Regulation of Epithelial and Mesenchymal Cell-Lineage Formation during Lung Development and Repair after Injury

    PubMed Central

    Bellusci, Saverio

    2014-01-01

    Basic research on embryonic lung development offers unique opportunities to make important discoveries that will impact human health. Developmental biologists interested in the molecular control of branching morphogenesis have intensively studied the developing lung, with its complex and seemingly stereotyped ramified structure. However, it is also an organ that is linked to a vast array of clinical problems in humans such as bronchopulmonary dysplasia in premature babies and emphysema, chronic obstructive pulmonary disease, fibrosis, and cancer in adults. Epithelial stem/progenitor cells reside in niches where they interact with specific extracellular matrices as well as with mesenchymal cells; the latter are still poorly characterized. Interactions of epithelial stem/progenitor cells with their microenvironments are usually instructive, controlling quiescence versus activation, proliferation, differentiation, and migration. During the past 18 years, Fgf10 has emerged not only as a marker for the distal lung mesenchyme during early lung development, but also as a key player in branching morphogenesis and a critical component of the niche for epithelial stem cells. In this paper, we will present the current knowledge regarding the lineage tree in the lung, with special emphasis on cell-lineage decisions in the lung mesenchyme and the role of Fgf10 in this context. PMID:25298902

  2. Walking along the Fibroblast Growth Factor 10 Route: A Key Pathway to Understand the Control and Regulation of Epithelial and Mesenchymal Cell-Lineage Formation during Lung Development and Repair after Injury.

    PubMed

    El Agha, Elie; Bellusci, Saverio

    2014-01-01

    Basic research on embryonic lung development offers unique opportunities to make important discoveries that will impact human health. Developmental biologists interested in the molecular control of branching morphogenesis have intensively studied the developing lung, with its complex and seemingly stereotyped ramified structure. However, it is also an organ that is linked to a vast array of clinical problems in humans such as bronchopulmonary dysplasia in premature babies and emphysema, chronic obstructive pulmonary disease, fibrosis, and cancer in adults. Epithelial stem/progenitor cells reside in niches where they interact with specific extracellular matrices as well as with mesenchymal cells; the latter are still poorly characterized. Interactions of epithelial stem/progenitor cells with their microenvironments are usually instructive, controlling quiescence versus activation, proliferation, differentiation, and migration. During the past 18 years, Fgf10 has emerged not only as a marker for the distal lung mesenchyme during early lung development, but also as a key player in branching morphogenesis and a critical component of the niche for epithelial stem cells. In this paper, we will present the current knowledge regarding the lineage tree in the lung, with special emphasis on cell-lineage decisions in the lung mesenchyme and the role of Fgf10 in this context. PMID:25298902

  3. Tendencies and Key Factors in the Health of School Students

    ERIC Educational Resources Information Center

    Rimashevskaia, N. M.; Shabunova, A. A.

    2013-01-01

    According to research data, in today's Russia 70 percent of children are born with various health risk factors, and this leads to a rapid deterioration of their health during their school years. The health of school students is getting worse as a consequence of the effect of a whole set of social and economic and psychological factors, and…

  4. Safety and reliability in industrial organizations - The key factors

    SciTech Connect

    Cooke, R.A. ); Sarkis, H.D. )

    1992-01-01

    A survey-based technique has been developed that measures and generates comparative data on important organizational, work group, and job-level variables that are directly related to on-the-job accidents. This paper describes the results of an analysis of data from more than 2,700 employees in the chemical, oil, construction, and wood products industries. These analyses indicate that several key variables are significantly related to accidents in the workplace.

  5. Psychological factors mediate key symptoms of fibromyalgia through their influence on stress.

    PubMed

    Malin, Katrina; Littlejohn, Geoffrey Owen

    2016-09-01

    The clinical features of fibromyalgia are associated with various psychological factors, including stress. We examined the hypothesis that the path that psychological factors follow in influencing fibromyalgia symptoms is through their direct effect on stress. Ninety-eight females with ACR 1990 classified fibromyalgia completed the following questionnaires: The Big 5 Personality Inventory, Fibromyalgia Impact Questionnaire, Perceived Stress Scale, Profile of Mood States, Mastery Scale, and Perceived Control of Internal States Scale. SPSS (PASW version 22) was used to perform basic t tests, means, and standard deviations to show difference between symptom characteristics. Pathway analysis using structural equation modelling (Laavan) examined the effect of stress on the relationships between psychological factors and the elements that define the fibromyalgia phenotype. The preferred model showed that the identified path clearly linked the psychological variables of anxiety, neuroticism and mastery, but not internal control, to the three key elements of fibromyalgia, namely pain, fatigue and sleep (p < 0.001), via the person's perceived stress. Confusion, however, did not fit the preferred model. This study confirms that stress is a necessary link in the pathway between certain identified, established and significant psychological factors and key fibromyalgia symptoms. This has implications for the understanding of contributing mechanisms and the clinical care of patients with fibromyalgia. PMID:27245234

  6. Succesful Lean Manufacturing Implementation: Internal Key Influencing Factors

    NASA Astrophysics Data System (ADS)

    Virginia, Iuga; Claudiu, Kifor

    2015-09-01

    Manufacturing sectors and companies all over the world are successfully implementing lean principles within their processes. Nowadays, lean has become an indispensable part of global players. Companies worldwide need to be aware of multiple factors which weigh heavily on the success or failure of lean implementation. This paper focuses on giving a brief and structured overview over the fundamental organizational factors which play a substantial role for the lean manufacturing (LM) implementation process. The study below focuses on internal factors which are indispensable for a successful LM implementation within organizations. It is imperative that these internal factors are known, recognized and taken into consideration during the whole LM implementation process. Ignoring their influence on the process's implementation may lead to endangering the expected results or to making the process more difficult which could result in much higher human resource consumption.

  7. Key Features of the TMD Soft-Factor Structure

    NASA Astrophysics Data System (ADS)

    Vladimirov, A.; Stefanis, N. G.

    2014-06-01

    We show that the geometry of the Wilson lines, entering the operator definition of the transverse-momentum dependent parton distributions and that of the soft factor, follows from the kinematics of the underlying physical process in conjunction with the gauge invariance of the QCD Lagrangian. We demonstrate our method in terms of concrete examples and determine the paths of the associated Wilson lines. The validation of the factorization theorem in our approach is postponed to future work.

  8. Ethylene, a key factor in the regulation of seed dormancy.

    PubMed

    Corbineau, Françoise; Xia, Qiong; Bailly, Christophe; El-Maarouf-Bouteau, Hayat

    2014-01-01

    Ethylene is an important component of the gaseous environment, and regulates numerous plant developmental processes including seed germination and seedling establishment. Dormancy, the inability to germinate in apparently favorable conditions, has been demonstrated to be regulated by the hormonal balance between abscisic acid (ABA) and gibberellins (GAs). Ethylene plays a key role in dormancy release in numerous species, the effective concentrations allowing the germination of dormant seeds ranging between 0.1 and 200 μL L(-1). Studies using inhibitors of ethylene biosynthesis or of ethylene action and analysis of mutant lines altered in genes involved in the ethylene signaling pathway (etr1, ein2, ain1, etr1, and erf1) demonstrate the involvement of ethylene in the regulation of germination and dormancy. Ethylene counteracts ABA effects through a regulation of ABA metabolism and signaling pathways. Moreover, ethylene insensitive mutants in Arabidopsis are more sensitive to ABA and the seeds are more dormant. Numerous data also show an interaction between ABA, GAs and ethylene metabolism and signaling pathways. It has been increasingly demonstrated that reactive oxygen species (ROS) may play a significant role in the regulation of seed germination interacting with hormonal signaling pathways. In the present review the responsiveness of seeds to ethylene will be described, and the key role of ethylene in the regulation of seed dormancy via a crosstalk between hormones and other signals will be discussed. PMID:25346747

  9. Ethylene, a key factor in the regulation of seed dormancy

    PubMed Central

    Corbineau, Françoise; Xia, Qiong; Bailly, Christophe

    2014-01-01

    Ethylene is an important component of the gaseous environment, and regulates numerous plant developmental processes including seed germination and seedling establishment. Dormancy, the inability to germinate in apparently favorable conditions, has been demonstrated to be regulated by the hormonal balance between abscisic acid (ABA) and gibberellins (GAs). Ethylene plays a key role in dormancy release in numerous species, the effective concentrations allowing the germination of dormant seeds ranging between 0.1 and 200 μL L-1. Studies using inhibitors of ethylene biosynthesis or of ethylene action and analysis of mutant lines altered in genes involved in the ethylene signaling pathway (etr1, ein2, ain1, etr1, and erf1) demonstrate the involvement of ethylene in the regulation of germination and dormancy. Ethylene counteracts ABA effects through a regulation of ABA metabolism and signaling pathways. Moreover, ethylene insensitive mutants in Arabidopsis are more sensitive to ABA and the seeds are more dormant. Numerous data also show an interaction between ABA, GAs and ethylene metabolism and signaling pathways. It has been increasingly demonstrated that reactive oxygen species (ROS) may play a significant role in the regulation of seed germination interacting with hormonal signaling pathways. In the present review the responsiveness of seeds to ethylene will be described, and the key role of ethylene in the regulation of seed dormancy via a crosstalk between hormones and other signals will be discussed. PMID:25346747

  10. The Human Factor: A Key to Excellence in Education.

    ERIC Educational Resources Information Center

    Mintzies, Paula; Hare, Isadora

    This document contends that efforts designed to determine how schools can educate children for the nation of tomorrow, by focusing primarily on curriculum issues, instruction, and teachers, may have overlooked the interpersonal factors which contribute to excellence and those human and social forces which may interfere with the attainment of…

  11. Key roles of necroptotic factors in promoting tumor growth.

    PubMed

    Liu, Xinjian; Zhou, Min; Mei, Ling; Ruan, Jiaying; Hu, Qian; Peng, Jing; Su, Hang; Liao, Hong; Liu, Shanling; Liu, WeiPing; Wang, He; Huang, Qian; Li, Fang; Li, Chuan-Yuan

    2016-04-19

    Necroptotic factors are generally assumed to play a positive role in tumor therapy by eliminating damaged tumor cells. Here we show that, contrary to expectation, necroptotic factors RIPK1, RIPK3, and MLKL promote tumor growth. We demonstrate that genetic knockout of necroptotic genes RIPK1, RIPK3, or MLKL in cancer cells significantly attenuated their abilities to grow in an anchorage-independent manner. In addition, they exhibited significantly enhanced radiosensitivity. The knockout cells also showed greatly reduced ability to form tumors in mice. Moreover, necrosulfonamide (NSA), a previously identified chemical inhibitor of necroptosis, could significantly delay tumor growth in a xenograft model. Mechanistically, we show that necroptoic factors play a significant role in maintaining the activity of NF-κB. Finally, we found that high levels of phosphorylated MLKL in human esophageal and colon cancers are associated with poor overall survival. Taken together, we conclude that pro-necroptic factors such as RIPK1, RIPK3, and MLKL may play a role in supporting tumor growth, and MLKL may be a promising target for cancer treatment. PMID:26959742

  12. Key roles of necroptotic factors in promoting tumor growth

    PubMed Central

    Liu, Xinjian; Zhou, Min; Mei, Ling; Ruan, Jiaying; Hu, Qian; Peng, Jing; Su, Hang; Liao, Hong; Liu, Shanling; Liu, WeiPing; Wang, He; Huang, Qian; Li, Fang; Li, Chuan-Yuan

    2016-01-01

    Necroptotic factors are generally assumed to play a positive role in tumor therapy by eliminating damaged tumor cells. Here we show that, contrary to expectation, necroptotic factors RIPK1, RIPK3, and MLKL promote tumor growth. We demonstrate that genetic knockout of necroptotic genes RIPK1, RIPK3, or MLKL in cancer cells significantly attenuated their abilities to grow in an anchorage-independent manner. In addition, they exhibited significantly enhanced radiosensitivity. The knockout cells also showed greatly reduced ability to form tumors in mice. Moreover, necrosulfonamide (NSA), a previously identified chemical inhibitor of necroptosis, could significantly delay tumor growth in a xenograft model. Mechanistically, we show that necroptoic factors play a significant role in maintaining the activity of NF-κB. Finally, we found that high levels of phosphorylated MLKL in human esophageal and colon cancers are associated with poor overall survival. Taken together, we conclude that pro-necroptic factors such as RIPK1, RIPK3, and MLKL may play a role in supporting tumor growth, and MLKL may be a promising target for cancer treatment. PMID:26959742

  13. Hypoxia-inducible factors as key regulators of tumor inflammation.

    PubMed

    Mamlouk, Soulafa; Wielockx, Ben

    2013-06-15

    Low levels of oxygen or hypoxia is often an obstacle in health, particularly in pathological disorders like cancer. The main family of transcription factors responsible for cell survival and adaptation under strenuous conditions of hypoxia are the "hypoxia-inducible factors" (HIFs). Together with prolyl hydroxylase domain enzymes (PHDs), HIFs regulates tumor angiogenesis, proliferation, invasion, metastasis, in addition to resistance to radiation and chemotherapy. Additionally, the entire HIF transcription cascade is involved in the "seventh" hallmark of cancer; inflammation. Studies have shown that hypoxia can influence tumor associated immune cells toward assisting in tumor proliferation, differentiation, vessel growth, distant metastasis and suppression of the immune response via cytokine expression alterations. These changes are not necessarily analogous to HIF's role in non-cancer immune responses, where hypoxia often encourages a strong inflammatory response. PMID:23055435

  14. Key parameters controlling the performance of catalytic motors

    NASA Astrophysics Data System (ADS)

    Esplandiu, Maria J.; Afshar Farniya, Ali; Reguera, David

    2016-03-01

    The development of autonomous micro/nanomotors driven by self-generated chemical gradients is a topic of high interest given their potential impact in medicine and environmental remediation. Although impressive functionalities of these devices have been demonstrated, a detailed understanding of the propulsion mechanism is still lacking. In this work, we perform a comprehensive numerical analysis of the key parameters governing the actuation of bimetallic catalytic micropumps. We show that the fluid motion is driven by self-generated electro-osmosis where the electric field originates by a proton current rather than by a lateral charge asymmetry inside the double layer. Hence, the surface potential and the electric field are the key parameters for setting the pumping strength and directionality. The proton flux that generates the electric field stems from the proton gradient induced by the electrochemical reactions taken place at the pump. Surprisingly the electric field and consequently the fluid flow are mainly controlled by the ionic strength and not by the conductivity of the solution, as one could have expected. We have also analyzed the influence of the chemical fuel concentration, electrochemical reaction rates, and size of the metallic structures for an optimized pump performance. Our findings cast light on the complex chemomechanical actuation of catalytic motors and provide important clues for the search, design, and optimization of novel catalytic actuators.

  15. Key parameters controlling the performance of catalytic motors.

    PubMed

    Esplandiu, Maria J; Afshar Farniya, Ali; Reguera, David

    2016-03-28

    The development of autonomous micro/nanomotors driven by self-generated chemical gradients is a topic of high interest given their potential impact in medicine and environmental remediation. Although impressive functionalities of these devices have been demonstrated, a detailed understanding of the propulsion mechanism is still lacking. In this work, we perform a comprehensive numerical analysis of the key parameters governing the actuation of bimetallic catalytic micropumps. We show that the fluid motion is driven by self-generated electro-osmosis where the electric field originates by a proton current rather than by a lateral charge asymmetry inside the double layer. Hence, the surface potential and the electric field are the key parameters for setting the pumping strength and directionality. The proton flux that generates the electric field stems from the proton gradient induced by the electrochemical reactions taken place at the pump. Surprisingly the electric field and consequently the fluid flow are mainly controlled by the ionic strength and not by the conductivity of the solution, as one could have expected. We have also analyzed the influence of the chemical fuel concentration, electrochemical reaction rates, and size of the metallic structures for an optimized pump performance. Our findings cast light on the complex chemomechanical actuation of catalytic motors and provide important clues for the search, design, and optimization of novel catalytic actuators. PMID:27036470

  16. Key characteristics for software for open architecture controllers

    NASA Astrophysics Data System (ADS)

    Pfeffer, Lawrence E.; Tran, Hy D.

    1997-01-01

    Software development time, cost, and ease of (re)use are now among the major issues in development of advanced machines, whether for machine tools, automation systems, or process systems. Two keys to reducing development time are powerful, user-friendly development tools and software architectures that provide clean, well-documented interfaces to the various real-time functions that such machines require. Examples of essential functions are signal conditioning, servo-control, trajectory generation, calibration/registration, coordination of a synchronous events, task sequencing, communication with external systems, and user interfaces. There are a number of existing standards that can help with software development, such as the IEEE POSIX standards for operating systems and real time services; software tools to compliment these standards are beginning to see use. This paper will detail some of the existing standards, some new tools, and development activities relevant to advanced, 'smart' machines.

  17. Key biogeochemical factors affecting soil carbon storage in Posidonia meadows

    NASA Astrophysics Data System (ADS)

    Serrano, Oscar; Ricart, Aurora M.; Lavery, Paul S.; Mateo, Miguel Angel; Arias-Ortiz, Ariane; Masque, Pere; Rozaimi, Mohammad; Steven, Andy; Duarte, Carlos M.

    2016-08-01

    Biotic and abiotic factors influence the accumulation of organic carbon (Corg) in seagrass ecosystems. We surveyed Posidonia sinuosa meadows growing in different water depths to assess the variability in the sources, stocks and accumulation rates of Corg. We show that over the last 500 years, P. sinuosa meadows closer to the upper limit of distribution (at 2-4 m depth) accumulated 3- to 4-fold higher Corg stocks (averaging 6.3 kg Corg m-2) at 3- to 4-fold higher rates (12.8 g Corg m-2 yr-1) compared to meadows closer to the deep limits of distribution (at 6-8 m depth; 1.8 kg Corg m-2 and 3.6 g Corg m-2 yr-1). In shallower meadows, Corg stocks were mostly derived from seagrass detritus (88 % in average) compared to meadows closer to the deep limit of distribution (45 % on average). In addition, soil accumulation rates and fine-grained sediment content (< 0.125 mm) in shallower meadows (2.0 mm yr-1 and 9 %, respectively) were approximately 2-fold higher than in deeper meadows (1.2 mm yr-1 and 5 %, respectively). The Corg stocks and accumulation rates accumulated over the last 500 years in bare sediments (0.6 kg Corg m-2 and 1.2 g Corg m-2 yr-1) were 3- to 11-fold lower than in P. sinuosa meadows, while fine-grained sediment content (1 %) and seagrass detritus contribution to the Corg pool (20 %) were 8- and 3-fold lower than in Posidonia meadows, respectively. The patterns found support the hypothesis that Corg storage in seagrass soils is influenced by interactions of biological (e.g., meadow productivity, cover and density), chemical (e.g., recalcitrance of Corg stocks) and physical (e.g., hydrodynamic energy and soil accumulation rates) factors within the meadow. We conclude that there is a need to improve global estimates of seagrass carbon storage accounting for biogeochemical factors driving variability within habitats.

  18. Key biogeochemical factors affecting soil carbon storage in Posidonia meadows

    NASA Astrophysics Data System (ADS)

    Serrano, O.; Ricart, A. M.; Lavery, P. S.; Mateo, M. A.; Arias-Ortiz, A.; Masque, P.; Steven, A.; Duarte, C. M.

    2015-11-01

    Biotic and abiotic factors influence the accumulation of organic carbon (Corg) in seagrass ecosystems. We surveyed Posidonia sinuosa meadows growing in different water depths to assess the variability in the sources, stocks and accumulation rates of Corg. We show that over the last 500 years, P. sinuosa meadows closer to the upper limit of distribution (at 2-4 m depth) accumulated 3 to 4-fold higher Corg stocks (averaging 6.3 kg Corg m-2) at 3 to 4-fold higher rates (12.8 g Corg m-2 yr-1) compared to meadows closer to the deep limits of distribution (at 6-8 m depth; 1.8 kg Corg m-2 and 3.6 g Corg m-2 yr-1). In shallower meadows, Corg stores were mostly derived from seagrass detritus (88 % in average) compared to meadows closer to the deep limit of distribution (45 % on average). Also, sediment accumulation rates and fine-grained sediment content (< 0.125 mm) in shallower meadows (2.0 mm yr-1 and 9 %, respectively) were approximately 2-fold higher than in deeper meadows (1.2 mm yr-1 and 5 %, respectively). The Corg stocks and accumulation rates accumulated over the last 500 years in bare sediments (0.6 kg Corg m-2 and 1.2 g Corg m-2 yr-1) were 3 to 11-fold lower than in P. sinuosa meadows, while fine-grained sediment content (1 %) and seagrass detritus contribution to the Corg pool (20 %) were 8 and 3-fold lower than in Posidonia meadows, respectively. The patterns found support the hypotheses that Corg storage in seagrass soils is influenced by interactions of biological (e.g. meadow productivity, cover and density), chemical (e.g. recalcitrance of Corg stocks) and physical (e.g. hydrodynamic energy and sediment accumulation rates) factors within the meadow. We conclude that there is a need to improve global estimates of seagrass carbon storage accounting for biogeochemical factors driving variability within habitats.

  19. Control of key pecan insect pests using biorational pesticides.

    PubMed

    Shapiro-Ilan, David I; Cottrell, Ted E; Jackson, Mark A; Wood, Bruce W

    2013-02-01

    Key pecan insect pests include the black pecan aphid, Melanocallis caryaefoliae (Davis), pecan weevil, Curculio caryae (Horn), and stink bugs (Hemiptera: Pentatomidae). Alternative control tactics are needed for management of these pests in organic and conventional systems. Our objective was to evaluate the potential utility of several alternative insecticides including three plant extract formulations, eucalyptus extract, citrus extract-8.92%, and citrus extract-19.4%, and two microbial insecticides, Chromobacterium subtsugae (Martin et al.) and Isaria fumosorosea (Wize). In the laboratory, eucalyptus extract, citrus extract-8.92%, citrus extract-19.4%, and C. subtsugae caused M. caryaefoliae mortality (mortality was reached approximately 78, 83, and 96%, respectively). In field tests, combined applications of I. fumosorosea with eucalyptus extract were synergistic and caused up to 82% mortality in M. caryaefoliae. In laboratory assays focusing on C. caryae suppression, C. subtsugae reduced feeding and oviposition damage, eucalyptus extract and citrus extract-19.4% were ineffective, and antagonism was observed when citrus extract-19.4% was combined with the entomopathogenic nematode, Steinernema carpocapsae (Weiser). In field tests, C. subtsugae reduced C. caryae damage by 55% within the first 3d, and caused 74.5% corrected mortality within 7 d posttreatment. In the laboratory, C. subtsugae and eucalyptus extract did not cause mortality in the brown stink bug, Euschistus servus (Say). Applications of C. subtsugae for suppression of C. caryae, and eucalyptus extract plus I. fumosorosea for control of M. caryaefoliae show promise as alternative insecticides and should be evaluated further. PMID:23448039

  20. Master transcription factors and mediator establish super-enhancers at key cell identity genes.

    PubMed

    Whyte, Warren A; Orlando, David A; Hnisz, Denes; Abraham, Brian J; Lin, Charles Y; Kagey, Michael H; Rahl, Peter B; Lee, Tong Ihn; Young, Richard A

    2013-04-11

    Master transcription factors Oct4, Sox2, and Nanog bind enhancer elements and recruit Mediator to activate much of the gene expression program of pluripotent embryonic stem cells (ESCs). We report here that the ESC master transcription factors form unusual enhancer domains at most genes that control the pluripotent state. These domains, which we call super-enhancers, consist of clusters of enhancers that are densely occupied by the master regulators and Mediator. Super-enhancers differ from typical enhancers in size, transcription factor density and content, ability to activate transcription, and sensitivity to perturbation. Reduced levels of Oct4 or Mediator cause preferential loss of expression of super-enhancer-associated genes relative to other genes, suggesting how changes in gene expression programs might be accomplished during development. In other more differentiated cells, super-enhancers containing cell-type-specific master transcription factors are also found at genes that define cell identity. Super-enhancers thus play key roles in the control of mammalian cell identity. PMID:23582322

  1. Key Factors Influencing Rapid Development of Potentially Dune-Stabilizing Moss-Dominated Crusts.

    PubMed

    Bu, Chongfeng; Zhang, Kankan; Zhang, Chunyun; Wu, Shufang

    2015-01-01

    Biological soil crusts (BSCs) are a widespread photosynthetic ground cover in arid and semiarid areas. They have many positive ecological functions, such as increasing soil stability, and reducing water and wind erosion. Using artificial technology to achieve the rapid development of BSCs is expected to become a low-cost and highly beneficial ecological restoration measure. In the present study, typical moss-dominated crusts in a region characterized by mobile dunes (Mu Us Sandland, China) were collected, and a 40-day cultivation experiment was performed to investigate key factors, including watering frequency, light intensity and a nutrient addition, which affect the rapid development of moss crusts and their optimal combination. The results demonstrated that watering frequency and illumination had a significant positive effect (P=0.049, three-factor ANOVA) and a highly significant, complicated effect (P=0.000, three-factor ANOVA), respectively, on the plant density of bryophytes, and a highly significant positive effect on the chlorophyll a and exopolysaccharide contents (P=0.000, P=0.000; P=0.000, P=0.000; one-way ANOVA). Knop nutrient solution did not have a significant positive but rather negative effect on the promotion of moss-dominated crust development (P=0.270, three-factor ANOVA). Moss-dominated crusts treated with the combination of moderate-intensity light (6,000 lx) + high watering frequency (1 watering/2 days) - Knop had the highest moss plant densities, while the treatment with high-intensity light (12,000 lx) + high watering frequency (1 watering/2 days) + Knop nutrient solution had higher chlorophyll a contents than that under other treatments. It is entirely feasible to achieve the rapid development of moss crusts under laboratory conditions by regulating key factors and creating the right environment. Future applications may seek to use cultured bryophytes to control erosion in vulnerable areas with urgent needs. PMID:26230324

  2. Key Factors Influencing Rapid Development of Potentially Dune-Stabilizing Moss-Dominated Crusts

    PubMed Central

    Bu, Chongfeng; Zhang, Kankan; Zhang, Chunyun; Wu, Shufang

    2015-01-01

    Biological soil crusts (BSCs) are a widespread photosynthetic ground cover in arid and semiarid areas. They have many positive ecological functions, such as increasing soil stability, and reducing water and wind erosion. Using artificial technology to achieve the rapid development of BSCs is expected to become a low-cost and highly beneficial ecological restoration measure. In the present study, typical moss-dominated crusts in a region characterized by mobile dunes (Mu Us Sandland, China) were collected, and a 40-day cultivation experiment was performed to investigate key factors, including watering frequency, light intensity and a nutrient addition, which affect the rapid development of moss crusts and their optimal combination. The results demonstrated that watering frequency and illumination had a significant positive effect (P=0.049, three-factor ANOVA) and a highly significant, complicated effect (P=0.000, three-factor ANOVA), respectively, on the plant density of bryophytes, and a highly significant positive effect on the chlorophyll a and exopolysaccharide contents (P=0.000, P=0.000; P=0.000, P=0.000; one-way ANOVA). Knop nutrient solution did not have a significant positive but rather negative effect on the promotion of moss-dominated crust development (P=0.270, three-factor ANOVA). Moss-dominated crusts treated with the combination of moderate-intensity light (6,000 lx) + high watering frequency (1 watering/2 days) - Knop had the highest moss plant densities, while the treatment with high-intensity light (12,000 lx) + high watering frequency (1 watering/2 days) + Knop nutrient solution had higher chlorophyll a contents than that under other treatments. It is entirely feasible to achieve the rapid development of moss crusts under laboratory conditions by regulating key factors and creating the right environment. Future applications may seek to use cultured bryophytes to control erosion in vulnerable areas with urgent needs. PMID:26230324

  3. Identification of Key Contributory Factors Responsible for Vascular Dysfunction in Idiopathic Recurrent Spontaneous Miscarriage

    PubMed Central

    Dutta, Mainak; Subramani, Elavarasan; Khalpada, Jaydeep; RoyChoudhury, Sourav; Chakravarty, Baidyanath; Chaudhury, Koel

    2013-01-01

    Poor endometrial perfusion during implantation window is reported to be one of the possible causes of idiopathic recurrent spontaneous miscarriage (IRSM). We have tested the hypothesis that certain angiogenic and vasoactive factors are associated with vascular dysfunction during implantation window in IRSM and, therefore, could play a contributory role in making the endometrium unreceptive in these women. This is a prospective case-controlled study carried out on 66 women with IRSM and age and BMI matched 50 fertile women serving as controls. Endometrial expression of pro-inflammatory (IL-1β, TNF-α, IFN-γ, TGF-β1), anti-inflammatory (IL-4, -10), angiogenesis-associated cytokines (IL-2, -6, -8), angiogenic and vasoactive factors including prostaglandin E2 (PGE2), vascular endothelial growth factor (VEGF), endothelial nitric oxide synthase (eNOS), nitric oxide (NO) and adrenomedullin (ADM) were measured during implantation window by ELISA. Subendometrial blood flow (SEBF) was assessed by color Doppler ultrasonography. Multivariate analysis was used to identify the significant factor(s) responsible for vascular dysfunction in IRSM women during window of implantation and further correlated with vascular dysfunction. Endometrial expression of pro-inflammatory cytokines and PGE2 were up-regulated and anti-inflammatory and angiogenesis-associated cytokines down-regulated in IRSM women as compared with controls. Further, the angiogenic and vasoactive factors including VEGF, eNOS, NO and ADM were found to be down-regulated and SEBF grossly affected in these women. Multivariate analysis identified IL-10, followed by VEGF and eNOS as the major factors contributing towards vascular dysfunction in IRSM women. Moreover, these factors strongly correlated with blood flow impairment. This study provides an understanding that IL-10, VEGF and eNOS are the principal key components having a contributory role in endometrial vascular dysfunction in women with IRSM. Down-regulation of

  4. The social determinants of health: key to global tuberculosis control.

    PubMed

    Rasanathan, K; Sivasankara Kurup, A; Jaramillo, E; Lönnroth, K

    2011-06-01

    Improved tuberculosis (TB) diagnosis and treatment through the DOTS and Stop TB strategies have saved millions of lives; however, their impact on TB incidence has been disappointing and the scale of the epidemic remains overwhelming. To reduce the incidence of TB, the drivers of the epidemic and social determinants of TB need to be addressed. These include co-morbidities and substance use and, moreover, the social and economic conditions that determine both the course of the TB epidemic and exposure to these risk factors. Doing so builds on the history of TB prevention and treatment during the public health revolution that resulted in a dramatic reduction in incidence in many countries. Addressing the social determinants is also imperative to address pervasive inequities in the incidence, mortality and morbidity of TB between different population groups, including in the performance of health systems in delivering diagnostic and treatment interventions, and in the financial consequences of people seeking care. Action on the social determinants can be categorised in terms of health-sector interventions, intersectoral policies impacting across society, and measurement and research to better understand inequities and links between TB and other factors. TB programmes cannot carry out these actions alone; however, they can make important contributions in the delivery of interventions and in advocating and negotiating for intersectoral efforts. The considerable progress seen in the clinical care of TB needs to be sustained; however, the attainment of TB targets, including elimination by 2050, will require expansion of the lens of TB control efforts beyond 'business as usual' to address the social determinants of the disease. PMID:21740657

  5. Enhanced Two-Factor Authentication and Key Agreement Using Dynamic Identities in Wireless Sensor Networks.

    PubMed

    Chang, I-Pin; Lee, Tian-Fu; Lin, Tsung-Hung; Liu, Chuan-Ming

    2015-01-01

    Key agreements that use only password authentication are convenient in communication networks, but these key agreement schemes often fail to resist possible attacks, and therefore provide poor security compared with some other authentication schemes. To increase security, many authentication and key agreement schemes use smartcard authentication in addition to passwords. Thus, two-factor authentication and key agreement schemes using smartcards and passwords are widely adopted in many applications. Vaidya et al. recently presented a two-factor authentication and key agreement scheme for wireless sensor networks (WSNs). Kim et al. observed that the Vaidya et al. scheme fails to resist gateway node bypassing and user impersonation attacks, and then proposed an improved scheme for WSNs. This study analyzes the weaknesses of the two-factor authentication and key agreement scheme of Kim et al., which include vulnerability to impersonation attacks, lost smartcard attacks and man-in-the-middle attacks, violation of session key security, and failure to protect user privacy. An efficient and secure authentication and key agreement scheme for WSNs based on the scheme of Kim et al. is then proposed. The proposed scheme not only solves the weaknesses of previous approaches, but also increases security requirements while maintaining low computational cost. PMID:26633396

  6. Enhanced Two-Factor Authentication and Key Agreement Using Dynamic Identities in Wireless Sensor Networks

    PubMed Central

    Chang, I-Pin; Lee, Tian-Fu; Lin, Tsung-Hung; Liu, Chuan-Ming

    2015-01-01

    Key agreements that use only password authentication are convenient in communication networks, but these key agreement schemes often fail to resist possible attacks, and therefore provide poor security compared with some other authentication schemes. To increase security, many authentication and key agreement schemes use smartcard authentication in addition to passwords. Thus, two-factor authentication and key agreement schemes using smartcards and passwords are widely adopted in many applications. Vaidya et al. recently presented a two-factor authentication and key agreement scheme for wireless sensor networks (WSNs). Kim et al. observed that the Vaidya et al. scheme fails to resist gateway node bypassing and user impersonation attacks, and then proposed an improved scheme for WSNs. This study analyzes the weaknesses of the two-factor authentication and key agreement scheme of Kim et al., which include vulnerability to impersonation attacks, lost smartcard attacks and man-in-the-middle attacks, violation of session key security, and failure to protect user privacy. An efficient and secure authentication and key agreement scheme for WSNs based on the scheme of Kim et al. is then proposed. The proposed scheme not only solves the weaknesses of previous approaches, but also increases security requirements while maintaining low computational cost. PMID:26633396

  7. Teachers' Professional Development: What Are the Key Change Factors for Mathematics Teachers?

    ERIC Educational Resources Information Center

    Pehkonen, Erkki; Torner, Gunter

    1999-01-01

    Surveyed and interviewed 13 experienced German middle school mathematics teachers to examine key factors causing discontinuity in their professional development. Results included 49 statements about change that fell into four categories. Researchers extracted three change factors not reported in earlier literature: experiences and observations…

  8. Part II--Factors Associated with School Nurse Ratios: Key State Informants' Perceptions

    ERIC Educational Resources Information Center

    Maughan, Erin

    2009-01-01

    This paper is the second of a two-part series examining factors influencing school nurse to pupil staffing ratios. The paper reports data from a qualitative study exploring the social and political factors that potentially influence ratios. Interviews were conducted with 30 key state informants from these states. Content analysis of the data…

  9. Lon protease: A key enzyme controlling mitochondrial bioenergetics in cancer

    PubMed Central

    Quirós, Pedro M; Bárcena, Clea; López-Otín, Carlos

    2014-01-01

    We have recently explored the in vivo functional and oncologic relevance of Lon protease (LONP1), an enzyme involved in mitochondrial quality control. We found that LONP1 is an essential protein for life and that it also performs a critical function in tumorigenesis by regulating the bioenergetics of cancer cells. PMID:27308364

  10. RM-DEMATEL: a new methodology to identify the key factors in PM2.5.

    PubMed

    Chen, Yafeng; Liu, Jie; Li, Yunpeng; Sadiq, Rehan; Deng, Yong

    2015-04-01

    Weather system is a relative complex dynamic system, the factors of the system are mutually influenced PM2.5 concentration. In this paper, a new method is proposed to quantify the influence on PM2.5 by other factors in the weather system and identify the most important factors for PM2.5 with limited resources. The relation map (RM) is used to figure out the direct relation matrix of 14 factors in PM2.5. The decision making trial and evaluation laboratory(DEMATEL) is applied to calculate the causal relationship and extent to a mutual influence of 14 factors in PM2.5. According to the ranking results of our proposed method, the most important key factors is sulfur dioxide (SO2) and nitrogen oxides (NO(X)). In addition, the other factors, the ambient maximum temperature (T(max)), concentration of PM10, and wind direction (W(dir)), are important factors for PM2.5. The proposed method can also be applied to other environment management systems to identify key factors. PMID:25728201

  11. Historical water control maps - key to understand current challenges?

    NASA Astrophysics Data System (ADS)

    Mészáros, János

    2014-05-01

    The 19th century and post-World War II decades were the main eras of water controlling in former Hungarian Kingdom and Hungary. Due to those large projects, the number and frequency of big floods were minimized but changes caused several other problems what we have to face off in the present. The main help to understand or highlight the fundamentals of those problems can be the flood control maps which, in some cases, show the original, natural riverbed and neighbouring areas of the river. There is other advantage of these maps compared to other surveys: while the main focus of the water control surveys was the river, there was sufficient time to measure the fine differences of land-use and relief in detail. Our sample area is the middle part of Tisza river and three different maps were chosen to show the changes before and after the regulations: Map of the Middle-Tisza, mapping until 1790 by János Lietzner This map is the earliest, known, topographic scale map about the river. Due to its age, the sheets are in bad state, especially their parts close to the edges and corners. A photographed, greyscale copy exists about the sheets, that was used in our research. Despite such bad conditions, it contains lots of information about the river and settlements, as well as detailed land-use before any flood regulation. New survey of Tisza river, mapping until 1932 by the Directorate of Water and Construction Because of the changes, due to time and regulation, several new surveys were ordered at the end of 19th century and between the world wars. During those new surveys, the river was re-triangulated and mapped, although cross and longitudinal section measurements also were carried out. This map clearly shows the results and changes of regulations, especially on populated areas, newly built dykes etc. but before the changes happened between 1950 and 1980. Topographic maps of the Hungarian Defence Forces - Geoinformation Services As a current, base-dataset, topographic maps

  12. Three-Phase Power Factor Controller

    NASA Technical Reports Server (NTRS)

    Nola, F. J.

    1982-01-01

    Three-Phase Power-Factor Controller develops a control signal for each motor winding. As motor loading decreases, rms value of applied voltage is decreased by feedback-control circuit. Power consumption is therefore lower than in unregulated operation. Controller employs phase detector for each of three phases of delta-connected induction motor. Phase-difference sum is basis for control.

  13. Key issues in controlling air pollutants in Dhaka, Bangladesh

    NASA Astrophysics Data System (ADS)

    Begum, Bilkis A.; Biswas, Swapan K.; Hopke, Philip K.

    2011-12-01

    Particulate matter (PM) sampling for both coarse and fine fractions was conducted in a semi-residential site (AECD) in Dhaka from February 2005 to December 2006. The samples were analyzed for mass, black carbon (BC), and elemental compositions. The resulting data set were analyzed for sources by Positive Matrix Factorization (EPA-PMF). From previous studies, it is found that, the air quality became worse in the dry winter period compared to the rainy season because of higher particulate matter concentration in the ambient air. Therefore, seasonal source contributions were determined from seasonally segregated data using EPA-PMF modeling so that further policy interventions can be undertaken to improve air quality. From the source apportionment results, it is observed that vehicular emissions and emission from brick kiln are the major contributors to air pollution in Dhaka especially in the dry seasons, while contribution from emissions from metal smelters increases during rainy seasons. The Government of Bangladesh is considering different interventions to reduce the emissions from those sources by adopting conversion of diesel/petrol vehicles to CNG, increasing traffic speed in the city and by introducing green technologies for brick production. However, in order to reduce the transboundary effect it is necessary to take action regionally.

  14. Ethylene Response Factors: A Key Regulatory Hub in Hormone and Stress Signaling.

    PubMed

    Müller, Maren; Munné-Bosch, Sergi

    2015-09-01

    Ethylene is essential for many developmental processes and a key mediator of biotic and abiotic stress responses in plants. The ethylene signaling and response pathway includes Ethylene Response Factors (ERFs), which belong to the transcription factor family APETALA2/ERF. It is well known that ERFs regulate molecular response to pathogen attack by binding to sequences containing AGCCGCC motifs (the GCC box), a cis-acting element. However, recent studies suggest that several ERFs also bind to dehydration-responsive elements and act as a key regulatory hub in plant responses to abiotic stresses. Here, we review some of the recent advances in our understanding of the ethylene signaling and response pathway, with emphasis on ERFs and their role in hormone cross talk and redox signaling under abiotic stresses. We conclude that ERFs act as a key regulatory hub, integrating ethylene, abscisic acid, jasmonate, and redox signaling in the plant response to a number of abiotic stresses. PMID:26103991

  15. Caudal, a key developmental regulator, is a DPE-specific transcriptional factor

    PubMed Central

    Juven-Gershon, Tamar; Hsu, Jer-Yuan; Kadonaga, James T.

    2008-01-01

    The regulation of gene transcription is critical for the proper development and growth of an organism. The transcription of protein-coding genes initiates at the RNA polymerase II core promoter, which is a diverse module that can be controlled by many different elements such as the TATA box and downstream core promoter element (DPE). To understand the basis for core promoter diversity, we explored potential biological functions of the DPE. We found that nearly all of the Drosophila homeotic (Hox) gene promoters, which lack TATA-box elements, contain functionally important DPE motifs that are conserved from Drosophila melanogaster to Drosophila virilis. We then discovered that Caudal, a sequence-specific transcription factor and key regulator of the Hox gene network, activates transcription with a distinct preference for the DPE relative to the TATA box. The specificity of Caudal activation for the DPE is particularly striking when a BREu core promoter motif is associated with the TATA box. These findings show that Caudal is a DPE-specific activator and exemplify how core promoter diversity can be used to establish complex regulatory networks. PMID:18923080

  16. Human Factors Engineering Program Review Model (NUREG-0711)Revision 3: Update Methodology and Key Revisions

    SciTech Connect

    OHara J. M.; Higgins, J.; Fleger, S.

    2012-07-22

    The U.S. Nuclear Regulatory Commission (NRC) reviews the human factors engineering (HFE) programs of applicants for nuclear power plant construction permits, operating licenses, standard design certifications, and combined operating licenses. The purpose of these safety reviews is to help ensure that personnel performance and reliability are appropriately supported. Detailed design review procedures and guidance for the evaluations is provided in three key documents: the Standard Review Plan (NUREG-0800), the HFE Program Review Model (NUREG-0711), and the Human-System Interface Design Review Guidelines (NUREG-0700). These documents were last revised in 2007, 2004 and 2002, respectively. The NRC is committed to the periodic update and improvement of the guidance to ensure that it remains a state-of-the-art design evaluation tool. To this end, the NRC is updating its guidance to stay current with recent research on human performance, advances in HFE methods and tools, and new technology being employed in plant and control room design. NUREG-0711 is the first document to be addressed. We present the methodology used to update NUREG-0711 and summarize the main changes made. Finally, we discuss the current status of the update program and the future plans.

  17. miR-122--a key factor and therapeutic target in liver disease.

    PubMed

    Bandiera, Simonetta; Pfeffer, Sébastien; Baumert, Thomas F; Zeisel, Mirjam B

    2015-02-01

    Being the largest internal organ of the human body with the unique ability of self-regeneration, the liver is involved in a wide variety of vital functions that require highly orchestrated and controlled biochemical processes. Increasing evidence suggests that microRNAs (miRNAs) are essential for the regulation of liver development, regeneration and metabolic functions. Hence, alterations in intrahepatic miRNA networks have been associated with liver disease including hepatitis, steatosis, cirrhosis and hepatocellular carcinoma (HCC). miR-122 is the most frequent miRNA in the adult liver, and a central player in liver biology and disease. Furthermore, miR-122 has been shown to be an essential host factor for hepatitis C virus (HCV) infection and an antiviral target, complementary to the standard of care using direct-acting antivirals or interferon-based treatment. This review summarizes our current understanding of the key role of miR-122 in liver physiology and disease, highlighting its role in HCC and viral hepatitis. We also discuss the perspectives of miRNA-based therapeutic approaches for viral hepatitis and liver disease. PMID:25308172

  18. Factors that Influence Policy Decisions in Literacy: Perspectives of Key Policy Informants

    ERIC Educational Resources Information Center

    Mraz, Maryann E.

    2004-01-01

    The purpose of this study was to examine the perspectives of key policy informants on the factors that they believed influence policy decisions in literacy education. Participants were selected because they had significantly influenced, or had attempted to influence, policy decisions in literacy at either the national or state level.…

  19. Key Motivational Factors in the Retention of Three Generations of Public High School Mathematics Teachers

    ERIC Educational Resources Information Center

    Pospichal, Wendy

    2011-01-01

    Purpose: The purpose of this study was to describe and compare the similarities and differences between five key motivational factors: (a) new teacher induction, (b) noninduction mentor support in the early years of teaching, (c) salary and benefits, (d) working conditions, and (e) administrative support influential in retention of employment in…

  20. Understanding Reusability as a Key Factor for Open Education: A Review

    ERIC Educational Resources Information Center

    Chiappe, Andres; Arias, Vivian

    2015-01-01

    This article describes both the process and the results of an extensive literature review on "reusability" as one of the key factors for the creation of open content in the context of open and distance learning. Qualitative analysis of texts was made from 1992 to early 2014 in order to identify meanings associated with reusability and…

  1. Agri-Environmental Resource Management by Large-Scale Collective Action: Determining KEY Success Factors

    ERIC Educational Resources Information Center

    Uetake, Tetsuya

    2015-01-01

    Purpose: Large-scale collective action is necessary when managing agricultural natural resources such as biodiversity and water quality. This paper determines the key factors to the success of such action. Design/Methodology/Approach: This paper analyses four large-scale collective actions used to manage agri-environmental resources in Canada and…

  2. Modeling and analysis of PM2.5 generation for key factors identification in China

    NASA Astrophysics Data System (ADS)

    Xia, Dehong; Jiang, Binfan; Xie, Yulei

    2016-06-01

    Recently, the PM2.5 pollution in China has occurred frequently and caused widely concern. In order to identify the key factors for PM2.5 generation, the formation characteristics of PM2.5 would be revealed. A property of electric neutrality of PM2.5 was proposed under the least-energy principle and verified through electricity-charge calculation in this paper. It indicated that PM2.5 is formed by the effect of electromagnetic force, including the effect of ionic bond, hydrogen bond and polarization. According to the analysis of interactive forces among different chemical components, a simulation model is developed for describing the random process of PM2.5 generation. In addition, an orthogonal test with two levels and four factors has been designed and carried out through the proposed model. From the text analysis, PM2.5 would be looser and suspend longer in atmosphere due to Organic Compound (OC) existing (OC can reduce about 67% of PM2.5 density). Considering that NH4+ is the only cation in the main chemical components of PM2.5, it would be vital for anions (such as SO42- and NO3-) to aggregate together for facilitating PM2.5 growing. Therefore, in order to relieve PM2.5 pollution, control strategies for OC and NH4+ would be enhanced by government through improving the quality of oils and solvent products, decreasing the amount of nitrogenous fertilizer utilization, or changing the fertilizing environment from dry condition to wet condition.

  3. Failure Detector for Power-Factor Controller

    NASA Technical Reports Server (NTRS)

    Nola, F. J.

    1982-01-01

    New protective circuits have been developed for power-factor ac motor controllers. Circuits prevent direct current and consequent motor heating that would normally result from failure of solid-state switch in controller. Single-phase power-factor controller with short detector compensates for short-circuit failure in either direction by applying full power to motor. Controller with open detector compensates for open-circuit failure in either direction by turning off power to motor.

  4. Power-Factor Controller With Regenerative Braking

    NASA Technical Reports Server (NTRS)

    Nola, F. J.

    1982-01-01

    Modified power-factor motor-control circuit operates motor as a phase-controlled generator when load attempts to turn at higher than synchronous speed. An induction motor is required to act at times as a brake. Circuit modification allows power-factor controller to save energy in motoring mode and convert automatically to an induction-generator controller in generating, or braking, mode.

  5. Key factors of readiness in the implementation of industrialised building system (IBS)

    NASA Astrophysics Data System (ADS)

    Tamrin, Norhidayah; Nawi, Mohd Nasrun Mohd; Nifa, Faizatul Akmar Abdul

    2016-08-01

    Although IBS has been introduced since the 1960, and many advantages that have identified for the implementation of IBS in Malaysia, yet the level of implementation of IBS still did not achieve the government target. Previous studies have been conducted to identify the factors that contribute to the lack of the implementation. From the previous studies, mostly the barriers of IBS implementation are rooted within the several semi-structured lack of readiness among industry players. The interview participants for this study are from the multidisciplinary IBS practitioners. This paper discusses the identified readiness with the objective to determine what the key factor of readiness in IBS implementation is and how far the factors influence the IBS activities. From the finding, the readiness factor was divided into three main factors which are knowledge, ability and planning.

  6. Which key properties controls the preferential transport in the vadose zone under transient hydrological conditions

    NASA Astrophysics Data System (ADS)

    Groh, J.; Vanderborght, J.; Puetz, T.; Gerke, H. H.; Rupp, H.; Wollschlaeger, U.; Stumpp, C.; Priesack, E.; Vereecken, H.

    2015-12-01

    % arrival time and potential key soil properties, site factors and boundary conditions will be presented in order to identify key properties which control the preferential transport in the vadose zone under transient hydrological conditions.

  7. Willingness to Pay for Mosquito Control in Key West, Florida and Tucson, Arizona.

    PubMed

    Dickinson, Katherine L; Hayden, Mary H; Haenchen, Steven; Monaghan, Andrew J; Walker, Kathleen R; Ernst, Kacey C

    2016-04-01

    Mosquito-borne illnesses like West Nile virus (WNV) and dengue are growing threats to the United States. Proactive mosquito control is one strategy to reduce the risk of disease transmission. In 2012, we measured the public's willingness to pay (WTP) for increased mosquito control in two cities: Key West, FL, where there have been recent dengue outbreaks, and Tucson, AZ, where dengue vectors are established and WNV has been circulating for over a decade. Nearly three quarters of respondents in both cities (74% in Tucson and 73% in Key West) would be willing to pay $25 or more annually toward an increase in publicly funded mosquito control efforts. WTP was positively associated with income (both cities), education (Key West), and perceived mosquito abundance (Tucson). Concerns about environmental impacts of mosquito control were associated with lower WTP in Key West. Expanded mosquito control efforts should incorporate public opinion as they respond to evolving disease risks. PMID:26903603

  8. Three-factor anonymous authentication and key agreement scheme for Telecare Medicine Information Systems.

    PubMed

    Arshad, Hamed; Nikooghadam, Morteza

    2014-12-01

    Nowadays, with comprehensive employment of the internet, healthcare delivery services is provided remotely by telecare medicine information systems (TMISs). A secure mechanism for authentication and key agreement is one of the most important security requirements for TMISs. Recently, Tan proposed a user anonymity preserving three-factor authentication scheme for TMIS. The present paper shows that Tan's scheme is vulnerable to replay attacks and Denial-of-Service attacks. In order to overcome these security flaws, a new and efficient three-factor anonymous authentication and key agreement scheme for TMIS is proposed. Security and performance analysis shows superiority of the proposed scheme in comparison with previously proposed schemes that are related to security of TMISs. PMID:25352490

  9. Socioeconomic status, family background and other key factors influence the management of head lice in Norway.

    PubMed

    Rukke, Bjørn Arne; Soleng, Arnulf; Lindstedt, Heidi Heggen; Ottesen, Preben; Birkemoe, Tone

    2014-05-01

    How head lice infestations are managed by households is an important but generally neglected issue in head lice research. In the present study, we investigate actions taken against head lice by Norwegian households in association with socioeconomic status, family background, school-related variables and other key factors. Repeat questionnaires distributed to caretakers of the same elementary school children during a 2-year period enabled us to study both previous head lice management and any changes in this management through time. Households from 12 schools spanning the main socioeconomic variation found in Norway participated in the study. All students with active head lice infestation were treated in the four investigated periods. Most caretakers used a thorough head lice checking technique and informed others of own infestation. Checking frequency was low as most children were inspected less than monthly. The best determinant of increased checking frequency and thoroughness was personal experience with head lice. The increased awareness, however, seemed to be somewhat short-lived, as there was a decrease in checking frequency and thoroughness within 1 year after infestation. Personal experience with head lice also increased general knowledge related to the parasite. Parents born in developing countries checked their children for head lice more frequently, although less thoroughly, informed fewer contacts when infested, used pediculicides preventively more often and knew less about head lice than parents born in developed countries. Households with highly educated mothers had a lower checking frequency, but their knowledge and willingness to inform others was high. Single parents were more concerned about economic costs and kept children home from school longer while infested than other parents. As head lice management varied among socioeconomic groups and with parental background, differentiated advice should be considered in the control of head lice. The

  10. Key Residues Regulating the Reductase Activity of the Human Mitochondrial Apoptosis Inducing Factor.

    PubMed

    Villanueva, Raquel; Ferreira, Patricia; Marcuello, Carlos; Usón, Alejandro; Miramar, M Dolores; Peleato, M Luisa; Lostao, Anabel; Susin, Santos A; Medina, Milagros

    2015-08-25

    The human Apoptosis Inducing Factor (hAIF) is a bifunctional NAD(P)H-dependent flavoreductase involved in both mitochondrial energy metabolism and caspase-independent cell death. Even though several studies indicate that both functions are redox controlled by NADH binding, the exact role of hAIF as a reductase in healthy mitochondria remains unknown. Upon reduction by NADH, hAIF dimerizes and produces very stable flavin/nicotinamide charge transfer complexes (CTC), by stacking of the oxidized nicotinamide moiety of the NAD(+) coenzyme against the re-face of the reduced flavin ring of its FAD cofactor. Such complexes are critical to restrict the hAIF efficiency as a reductase. The molecular basis of the hAIF reductase activity is here investigated by analyzing the role played by residues contributing to the interaction of the FAD isoalloxazine ring and of the nicotinamide moiety of NADH at the active site. Mutations at K177 and E314 produced drastic effects on the hAIF ability to retain the FAD cofactor, indicating that these residues are important to set up the holo-enzyme active site conformation. Characterization of P173G hAIF indicates that the stacking of P173 against the isoalloxazine ring is relevant to determine the flavin environment and to modulate the enzyme affinity for NADH. Finally, the properties of the F310G and H454S hAIF mutants indicate that these two positions contribute to form a compact active site essential for NADH binding, CTC stabilization, and NAD(+) affinity for the reduced state of hAIF. These features are key determinants of the particular behavior of hAIF as a NADH-dependent oxidoreductase. PMID:26237213

  11. Evolving Systems: Nonlinear Adaptive Key Component Control with Persistent Disturbance Rejection

    NASA Technical Reports Server (NTRS)

    Balas, Mark J.; Frost, Susan A.

    2013-01-01

    This paper presents an introduction to Evolving Systems, which are autonomously controlled subsystems that self-assemble into a new Evolved System with a higher purpose. Evolving Systems of aerospace structures often require additional control when assembling to maintain stability during the entire evolution process. This is the concept of Adaptive Key Component Control which operates through one specific component to maintain stability during the evolution. In addition this control must overcome persistent disturbances that occur while the evolution is in progress. We present theoretical results for the successful operation of Nonlinear Adaptive Key Component control in the presence of such disturbances and an illustrative example.

  12. Key success factors for clinical knowledge management systems: Comparing physician and hospital manager viewpoints.

    PubMed

    Chang, Sho-Fang; Hsieh, Ping-Jung; Chen, Hui-Fang

    2015-01-01

    The study explores the perceptions of physicians and hospital managers regarding the key success factors (KSFs) of a clinical knowledge management system (CKMS). It aims to eliminate the perception gap and gain more insights for a successful CKMS.A survey was conducted in four medical centers in Taiwan. A total of 340 questionnaires, including 15 for hospital managers and 70 for physicians in each hospital, were administered. The effective response rates are 78.3% and 56.1% respectively. Partial least square (PLS) were used to analyze the data.The results identified six KSFs of CKMS including system software and hardware, knowledge quality, system quality, organizational factors, user satisfaction, and policy factors. User satisfaction and policy factors have direct effects on perceived CKMS performance. Knowledge quality is regarded as an antecedent to user satisfaction, while system quality is the antecedent to both user satisfaction and policy factors. System software and hardware was supported only by managers, and organizational factors were supported only by physicians.Among the factors, this study highlighted the policy factor. Besides, the study provides hospital managers additional insights into physician requirements for organizational support. Third, more physician participation and involvement are recommended when introducing and developing a CKMS. PMID:26444813

  13. ROLE OF DOM PHOTOREACTIONS IN CONTROLLING UV EXPOSURE OF CORAL ASSEMBLAGES IN THE FLORIDA KEYS

    EPA Science Inventory

    Recent studies have indicated that solar LTV radiation is a significant stressor of coral assemblages in tropical and subtropical marine environments. Here evidence is presented that UV exposure of coral reefs in the Florida Keys near Key West is controlled by the colored compone...

  14. KEY PUBLICATIONS (EMISSIONS CHARACTERIZATION AND PREVENTION BRANCH, AIR POLLUTION PREVENTION AND CONTROL DIVISION, NRMRL)

    EPA Science Inventory

    The Emissions Characterization and Prevention Branch (ECPB) of NRMRL's Air Pollution Prevention and Control Division in Research Triangle Park, NC, produces highly specialized scientific and technical documents relating to ECPB's research areas. A list of key publications coveri...

  15. Identifying the key factors affecting warning message dissemination in VANET real urban scenarios.

    PubMed

    Fogue, Manuel; Garrido, Piedad; Martinez, Francisco J; Cano, Juan-Carlos; Calafate, Carlos T; Manzoni, Pietro

    2013-01-01

    In recent years, new architectures and technologies have been proposed for Vehicular Ad Hoc networks (VANETs). Due to the cost and complexity of deploying such networks, most of these proposals rely on simulation. However, we find that most of the experiments made to validate these proposals tend to overlook the most important and representative factors. Moreover, the scenarios simulated tend to be very simplistic (highways or Manhattan-based layouts), which could seriously affect the validity of the obtained results. In this paper, we present a statistical analysis based on the 2k factorial methodology to determine the most representative factors affecting traffic safety applications under real roadmaps. Our purpose is to determine which are the key factors affecting Warning Message Dissemination in order to concentrate research tests on such parameters, thus avoiding unnecessary simulations and reducing the amount of simulation time required. Simulation results show that the key factors affecting warning messages delivery are the density of vehicles and the roadmap used. Based on this statistical analysis, we consider that VANET researchers must evaluate the benefits of their proposals using different vehicle densities and city scenarios, to obtain a broad perspective on the effectiveness of their solution. Finally, since city maps can be quite heterogeneous, we propose a roadmap profile classification to further reduce the number of cities evaluated. PMID:23604026

  16. Identifying the Key Factors Affecting Warning Message Dissemination in VANET Real Urban Scenarios

    PubMed Central

    Fogue, Manuel; Garrido, Piedad; Martinez, Francisco J.; Cano, Juan-Carlos; Calafate, Carlos T.; Manzoni, Pietro

    2013-01-01

    In recent years, new architectures and technologies have been proposed for Vehicular Ad Hoc networks (VANETs). Due to the cost and complexity of deploying such networks, most of these proposals rely on simulation. However, we find that most of the experiments made to validate these proposals tend to overlook the most important and representative factors. Moreover, the scenarios simulated tend to be very simplistic (highways or Manhattan-based layouts), which could seriously affect the validity of the obtained results. In this paper, we present a statistical analysis based on the 2k factorial methodology to determine the most representative factors affecting traffic safety applications under real roadmaps. Our purpose is to determine which are the key factors affecting Warning Message Dissemination in order to concentrate research tests on such parameters, thus avoiding unnecessary simulations and reducing the amount of simulation time required. Simulation results show that the key factors affecting warning messages delivery are the density of vehicles and the roadmap used. Based on this statistical analysis, we consider that VANET researchers must evaluate the benefits of their proposals using different vehicle densities and city scenarios, to obtain a broad perspective on the effectiveness of their solution. Finally, since city maps can be quite heterogeneous, we propose a roadmap profile classification to further reduce the number of cities evaluated. PMID:23604026

  17. Ephemeral gully: soil control factors

    NASA Astrophysics Data System (ADS)

    Ollobarren, Paul; Giménez, Rafael; Ángel Campo, Miguel; Casalí, Javier

    2014-05-01

    Soil erosion on hillslopes has been divided traditionally into sheet, rill, and (ephemeral) gully erosion. In sheet erosion, a relatively shallow overland flow acts on a hillslope and removes sediment particles uniformly from the land surface. Usually, rill erosion occur in uncertain points within sloping surfaces, whereas gullies occur in more specific places in the landscapes, i.e., within topographic swales or hollows. So that, current models for prediction of (ephemeral) gully initiation and development rely mainly on topographic factors while soil conditions are almost neglected. However, the assessment of the erodibility of soil materials is essential for analyzing and properly modeling gully erosion. But, despite the wealth of studies to characterize soil vulnerability to (gully) erosion, a universal approach is still lacking. This is due to the complexity of soil conditions and erosion phenomenon and their interactions. A useful and feasible soil characterization for gully erosion prediction at large scale should be based on simple, quick, repeatable and relatively inexpensive tests to perform. This work proposes a methodology for conducting simple tests in the field and laboratory to detect soil conditions prone to gully initiation. This approach for assessing soil erodibility includes the use of vane shear apparatus, penetrometers and a mini-rain simulator as well as some current (modified) laboratory tests for assessing soil crustability and erodibility. A pool of simple soil variables to assess soils prone to gully development is proposed. Among the main variables we have the granulometric composition of the top soil (textural fractions and gravel), organic matter content, soil cohesiveness and relative sensitivity of topsoils for crusting. Our finding may be particularly useful for erosion modelling when gully initiation and development do not largely rely on topographic features but in soil conditions.

  18. A key genetic factor for fucosyllactose utilization affects infant gut microbiota development

    PubMed Central

    Matsuki, Takahiro; Yahagi, Kana; Mori, Hiroshi; Matsumoto, Hoshitaka; Hara, Taeko; Tajima, Saya; Ogawa, Eishin; Kodama, Hiroko; Yamamoto, Kazuya; Yamada, Takuji; Matsumoto, Satoshi; Kurokawa, Ken

    2016-01-01

    Recent studies have demonstrated that gut microbiota development influences infants' health and subsequent host physiology. However, the factors shaping the development of the microbiota remain poorly understood, and the mechanisms through which these factors affect gut metabolite profiles have not been extensively investigated. Here we analyse gut microbiota development of 27 infants during the first month of life. We find three distinct clusters that transition towards Bifidobacteriaceae-dominant microbiota. We observe considerable differences in human milk oligosaccharide utilization among infant bifidobacteria. Colonization of fucosyllactose (FL)-utilizing bifidobacteria is associated with altered metabolite profiles and microbiota compositions, which have been previously shown to affect infant health. Genome analysis of infants' bifidobacteria reveals an ABC transporter as a key genetic factor for FL utilization. Thus, the ability of bifidobacteria to utilize FL and the presence of FL in breast milk may affect the development of the gut microbiota in infants, and might ultimately have therapeutic implications. PMID:27340092

  19. A key genetic factor for fucosyllactose utilization affects infant gut microbiota development.

    PubMed

    Matsuki, Takahiro; Yahagi, Kana; Mori, Hiroshi; Matsumoto, Hoshitaka; Hara, Taeko; Tajima, Saya; Ogawa, Eishin; Kodama, Hiroko; Yamamoto, Kazuya; Yamada, Takuji; Matsumoto, Satoshi; Kurokawa, Ken

    2016-01-01

    Recent studies have demonstrated that gut microbiota development influences infants' health and subsequent host physiology. However, the factors shaping the development of the microbiota remain poorly understood, and the mechanisms through which these factors affect gut metabolite profiles have not been extensively investigated. Here we analyse gut microbiota development of 27 infants during the first month of life. We find three distinct clusters that transition towards Bifidobacteriaceae-dominant microbiota. We observe considerable differences in human milk oligosaccharide utilization among infant bifidobacteria. Colonization of fucosyllactose (FL)-utilizing bifidobacteria is associated with altered metabolite profiles and microbiota compositions, which have been previously shown to affect infant health. Genome analysis of infants' bifidobacteria reveals an ABC transporter as a key genetic factor for FL utilization. Thus, the ability of bifidobacteria to utilize FL and the presence of FL in breast milk may affect the development of the gut microbiota in infants, and might ultimately have therapeutic implications. PMID:27340092

  20. Phase Detector for Power-Factor Controller

    NASA Technical Reports Server (NTRS)

    Nola, F. J.

    1984-01-01

    Positive feedback assures reliable switching. Three Phase Power Factor Controller includes three phase detectors, each produces rectangular waves of duration approximately equal to lag time between line voltage and motor current.

  1. Detection of key factors in the extraction and quantification of lycopene from tomato and tomato products.

    PubMed

    Periago, María Jesús; Rincón, Francisco; Jacob, Karin; García-Alonso, Javier; Ros, Gaspar

    2007-10-31

    The analytical process of lycopene extraction and photometrical determination was critically examined for raw tomato and processed tomato products by means of a 2 IV (15-10) Plackett-Burman experimental design in order to identify the key factors (KFs) involved. Fifteen apparent key factors (AKFs) reported in the literature were selected: sample weight (X1); volume of extraction solution (X2); antioxidant concentration (BHT, X3); neutralizing agent concentration (MgCO 3, X4); light presence during lycopene extraction (X5), homogenization velocity (X6) and time (X7), agitation time (X8), and temperature (X9) during the extraction process; water volume for separation of polar/nonpolar phases (X11); presence of inert atmosphere throughout the process (X12); time (X13), temperature (X14), and light presence (X10) during separation of phases and time delay for reading (X15). In general, higher lycopene concentrations in samples led to a higher number of key factors (KF). Thus, for raw tomato (lycopene range 1.22-2.29 mg/100 g) no KF were found, whereas for tomato sauce (lycopene range from 5.80 to 8.60 mg/100 g) one KF (X4) and for tomato paste (lycopene range from 35.80 to 51.27 mg/100 g) five KFs (X1, X2, X4, X11, and X12) were detected. For lycopene paste, X1 and X2 were identified as the KFs with the greatest impact on results, although in fact the X1/X2 ratio was the real cause. The results suggest that, with increased processing, the physical and chemical structure of lycopene becomes less important since the identified KFs explain almost 90% of variability in tomato paste but only 32% in raw tomato. PMID:17924704

  2. Thermal control of virulence factors in bacteria: A hot topic

    PubMed Central

    Lam, Oliver; Wheeler, Jun; Tang, Christoph M

    2014-01-01

    Pathogenic bacteria sense environmental cues, including the local temperature, to control the production of key virulence factors. Thermal regulation can be achieved at the level of DNA, RNA or protein and although many virulence factors are subject to thermal regulation, the exact mechanisms of control are yet to be elucidated in many instances. Understanding how virulence factors are regulated by temperature presents a significant challenge, as gene expression and protein production are often influenced by complex regulatory networks involving multiple transcription factors in bacteria. Here we highlight some recent insights into thermal regulation of virulence in pathogenic bacteria. We focus on bacteria which cause disease in mammalian hosts, which are at a significantly higher temperature than the outside environment. We outline the mechanisms of thermal regulation and how understanding this fundamental aspect of the biology of bacteria has implications for pathogenesis and human health. PMID:25494856

  3. Key Items to Get Right When Conducting a Randomized Controlled Trial in Education

    ERIC Educational Resources Information Center

    Coalition for Evidence-Based Policy, 2005

    2005-01-01

    This is a checklist of key items to get right when conducting a randomized controlled trial to evaluate an educational program or practice ("intervention"). It is intended as a practical resource for researchers and sponsors of research, describing items that are often critical to the success of a randomized controlled trial. A significant…

  4. Factors Determining Adolescent Locus of Control.

    ERIC Educational Resources Information Center

    Kopera-Frye, Karen F.; And Others

    Previous research has demonstrated an association between locus of control in adolescence and a successful transition to adulthood. Having an external locus of control has been implicated as an important factor in adolescent behaviors such as teenage pregnancy and delinquency, and has been found to be negatively related to school achievement. This…

  5. Identifying sensitive sources and key control handles for the reduction of greenhouse gas emissions from wastewater treatment.

    PubMed

    Sweetapple, Christine; Fu, Guangtao; Butler, David

    2014-10-01

    This research investigates the effects of adjusting control handle values on greenhouse gas emissions from wastewater treatment, and reveals critical control handles and sensitive emission sources for control through the combined use of local and global sensitivity analysis methods. The direction of change in emissions, effluent quality and operational cost resulting from variation of control handles individually is determined using one-factor-at-a-time sensitivity analysis, and corresponding trade-offs are identified. The contribution of each control handle to variance in model outputs, taking into account the effects of interactions, is then explored using a variance-based sensitivity analysis method, i.e., Sobol's method, and significant second order interactions are discovered. This knowledge will assist future control strategy development and aid an efficient design and optimisation process, as it provides a better understanding of the effects of control handles on key performance indicators and identifies those for which dynamic control has the greatest potential benefits. Sources with the greatest variance in emissions, and therefore the greatest need to monitor, are also identified. It is found that variance in total emissions is predominantly due to changes in direct N2O emissions and selection of suitable values for wastage flow rate and aeration intensity in the final activated sludge reactor is of key importance. To improve effluent quality, costs and/or emissions, it is necessary to consider the effects of adjusting multiple control handles simultaneously and determine the optimum trade-off. PMID:24960125

  6. Analysis of Hypoxia-Inducible Factor-1α Expression Relative to Other Key Factors in Malignant Canine Mammary Tumours.

    PubMed

    Shin, J-I; Lim, H-Y; Kim, H-W; Seung, B-J; Sur, J-H

    2015-01-01

    Hypoxia-inducible factor (HIF)-1α plays important physiological roles, but is also of significance in carcinogenesis in man and animals. This study aimed to identify HIF-1α expression in malignant canine mammary tumours (CMTs) and to find correlations with other key factors by using immunohistochemistry (IHC). The histological classification, grading and evaluation of lymphatic invasion were achieved by examining sections stained by haematoxylin and eosin. Determination of molecular subtype, expression of HIF-1α, oestrogen receptor (OR), progesterone receptor (PR), human epidermal growth factor receptor (HER)-2, Ki67, vascular endothelial growth factor (VEGF) and E-cadherin was evaluated by IHC in 87 samples of malignant CMTs. HIF-1α expression correlated significantly with histological type, grade of cancer, negativity for OR and expression of Ki67 and VEGF. Lymphatic invasion, molecular subtype, PR, HER-2 and E-cadherin levels did not significantly correlate with HIF-1α expression. The results of this study imply that HIF-1α may potentially play a role in increased malignancy of CMTs, as it does in human breast cancer. PMID:26145724

  7. Aircraft Loss of Control Causal Factors and Mitigation Challenges

    NASA Technical Reports Server (NTRS)

    Jacobson, Steven R.

    2010-01-01

    Loss of control is the leading cause of jet fatalities worldwide. Aside from their frequency of occurrence, accidents resulting from loss of aircraft control seize the public s attention by yielding a large number of fatalities in a single event. In response to the rising threat to aviation safety, the NASA Aviation Safety Program has conducted a study of the loss of control problem. This study gathered four types of information pertaining to loss of control accidents: (1) statistical data; (2) individual accident reports that cite loss of control as a contributing factor; (3) previous meta-analyses of loss of control accidents; and (4) inputs solicited from aircraft manufacturers, air carriers, researchers, and other industry stakeholders. Using these information resources, the study team identified the causal factors that were cited in the greatest number of loss of control accidents, and which were emphasized most by industry stakeholders. This report describes the study approach, the key causal factors for aircraft loss of control, and recommended mitigation strategies to make near-term impacts, mid-term impacts, and Next Generation Air Transportation System impacts on the loss of control accident statistics

  8. Human factors challenges for advanced process control

    SciTech Connect

    Stubler, W.F.; O`Hara, J..M.

    1996-08-01

    New human-system interface technologies provide opportunities for improving operator and plant performance. However, if these technologies are not properly implemented, they may introduce new challenges to performance and safety. This paper reports the results from a survey of human factors considerations that arise in the implementation of advanced human-system interface technologies in process control and other complex systems. General trends were identified for several areas based on a review of technical literature and a combination of interviews and site visits with process control organizations. Human factors considerations are discussed for two of these areas, automation and controls.

  9. Commercialization of the power factor controller

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The purpose of the Motor Power Controller, also known as the Power Factor Controller, is to improve power factor and reduce power dissipation in induction motors operating below full load. These purposes were studied and tested in detail. The Motor Power Controller is capable of raising power factors from 0.2 to 0.8 and results in energy savings. It was found that many motors, in their present operating applications, are classified as unstable. The electronic nature of the controller vs. the electrical nature of the motor, compound this problem due to the differences in response time of the two devices. Many tests were successfully completed, the most indicating greater savings than anticipated. Also, there was an effect on efficiency which was not included in the calculations.

  10. Controlling Continuous-Variable Quantum Key Distribution with Tuned Linear Optics Cloning Machines

    NASA Astrophysics Data System (ADS)

    Guo, Ying; Qiu, Deli; Huang, Peng; Zeng, Guihua

    2015-09-01

    We show that the tolerable excess noise can be elegantly controlled while inserting a tunable linear optics cloning machine (LOCM) for continuous-variable key distribution (CVQKD). The LOCM-tuned noise can be stabilized to an optimal value by the reference partner of reconciliation to guarantee the high secret key rate. Simulation results show that there is a considerable improvement of the performance for the LOCM-based CVQKD protocol in terms of the secret rate while making a fine balance between the secret key rate and the transmission distance with the dynamically tuned parameters in suitable ranges.

  11. Factors Enabling Access to HIV Voluntary Counseling and Testing for Key Affected Populations in Thailand.

    PubMed

    Thepthien, Bang-on; Srivanichakorn, Supattra; Apipornchaisakul, Kanya

    2015-10-01

    The objective was to study the factors that enabled persons at risk of HIV to obtain voluntary counseling and testing (VCT) in Thailand. This research was a cross-sectional study and data were collected during May to July 2013 in 8, purposively selected provinces. The method for selecting respondents used time-location quota sampling to achieve a total sample of 751 persons. The proportion who had VCT in the year prior to the survey was 56%.The significant enabling factors associated with VCT were having someone encourage them to go for testing and receiving information about VCT In addition, other significant factors for female sex workers were self-assessed risk for HIV and having had risk behavior, and for men who have sex with men the factors were awareness of eligibility for VCT. Thus, in order to achieve the VCT target for higher risk populations by 2016, there should be special mechanisms to inform the different groups, along with improvements in outreach services to make VCT more convenient for key affected populations. PMID:26069165

  12. Reliable and Affordable Control Systems Active Combustor Pattern Factor Control

    NASA Technical Reports Server (NTRS)

    McCarty, Bob; Tomondi, Chris; McGinley, Ray

    2004-01-01

    Active, closed-loop control of combustor pattern factor is a cooperative effort between Honeywell (formerly AlliedSignal) Engines and Systems and the NASA Glenn Research Center to reduce emissions and turbine-stator vane temperature variations, thereby enhancing engine performance and life, and reducing direct operating costs. Total fuel flow supplied to the engine is established by the speed/power control, but the distribution to individual atomizers will be controlled by the Active Combustor Pattern Factor Control (ACPFC). This system consist of three major components: multiple, thin-film sensors located on the turbine-stator vanes; fuel-flow modulators for individual atomizers; and control logic and algorithms within the electronic control.

  13. MYC TRANSCRIPTION FACTORS: KEY REGULATORS BEHIND ESTABLISHMENT AND MAINTENANCE OF PLURIPOTENCY

    PubMed Central

    Smith, Keriayn; Dalton, Stephen

    2011-01-01

    Summary The interplay between transcription factors, epigenetic modifiers, chromatin remodelers and miRNAs form the foundation of a complex regulatory network required for establishment and maintenance of the pluripotent state. Recent work indicates that Myc transcription factors are essential elements of this regulatory system. Despite numerous reports however, aspects of how Myc controls self-renewal and pluripotency remain obscure. Here, we review evidence supporting the placement of Myc as a central regulator of the pluripotent state and discuss possible mechanisms of action. PMID:21082893

  14. Fuzzy control of power factor preregulators

    SciTech Connect

    Mattavelli, P.; Buso, S.; Spiazzi, G.; Tenti, P.

    1995-12-31

    In this paper, a fuzzy-logic-based controller for Power Factor Preregulators (PFP`s) is investigated. Through this approach it is possible to get low-distorted and in-phase line current without need for sophisticated mathematical analysis or complex models to design the controller. Moreover, the intrinsic non-linearity of this control technique allows improved dynamic response and increased robustness as compared to linear approaches. In this paper, controller design and operation are discussed, and implementation by a microcontroller is described. Actual converter operation is analyzed by simulation in the case of a boost PFP, demonstrating the feasibility of the approach.

  15. Surgical Ventricular Entry is a Key Risk Factor for Leptomeningeal Metastasis of High Grade Gliomas

    PubMed Central

    Roelz, Roland; Reinacher, Peter; Jabbarli, Ramazan; Kraeutle, Rainer; Hippchen, Beate; Egger, Karl; Weyerbrock, Astrid; Machein, Marcia

    2015-01-01

    Leptomeningeal metastasis (LM) of high grade gliomas (HGG) can lead to devastating disease courses. Understanding of risk factors for LM is important to identify patients at risk. We reviewed patient records and magnetic resonance imaging (MRI) of all patients with a first diagnosis of HGG who underwent surgery in our institution between 2008 and 2012. To assess the influence of potential risk factors for LM and the impact of LM on survival multivariate statistics were performed. 239 patients with a diagnosis of HGG and at least 6 months of MRI and clinical follow-up were included. LM occurred in 27 (11%) patients and was symptomatic in 17 (65%). A strong correlation of surgical entry to the ventricle and LM was found (HR: 8.1). Ventricular entry was documented in 137 patients (57%) and LM ensued in 25 (18%) of these. Only two (2%) of 102 patients without ventricular entry developed LM. Median overall survival of patients after diagnosis of LM (239 days) was significantly shorter compared to patients without LM (626 days). LM is a frequent complication in the course of disease of HGG and is associated with poor survival. Surgical entry to the ventricle is a key risk factor for LM. PMID:26635136

  16. Transcription Factor RFX2 Is a Key Regulator of Mouse Spermiogenesis.

    PubMed

    Wu, Yujian; Hu, Xiangjing; Li, Zhen; Wang, Min; Li, Sisi; Wang, Xiuxia; Lin, Xiwen; Liao, Shangying; Zhang, Zhuqiang; Feng, Xue; Wang, Si; Cui, Xiuhong; Wang, Yanling; Gao, Fei; Hess, Rex A; Han, Chunsheng

    2016-01-01

    The regulatory factor X (RFX) family of transcription factors is crucial for ciliogenesis throughout evolution. In mice, Rfx1-4 are highly expressed in the testis where flagellated sperm are produced, but the functions of these factors in spermatogenesis remain unknown. Here, we report the production and characterization of the Rfx2 knockout mice. The male knockout mice were sterile due to the arrest of spermatogenesis at an early round spermatid step. The Rfx2-null round spermatids detached from the seminiferous tubules, forming large multinucleated giant cells that underwent apoptosis. In the mutants, formation of the flagellum was inhibited at its earliest stage. RNA-seq analysis identified a large number of cilia-related genes and testis-specific genes that were regulated by RFX2. Many of these genes were direct targets of RFX2, as revealed by chromatin immunoprecipitation-PCR assays. These findings indicate that RFX2 is a key regulator of the post-meiotic development of mouse spermatogenic cells. PMID:26853561

  17. Transcription Factor RFX2 Is a Key Regulator of Mouse Spermiogenesis

    PubMed Central

    Wu, Yujian; Hu, Xiangjing; Li, Zhen; Wang, Min; Li, Sisi; Wang, Xiuxia; Lin, Xiwen; Liao, Shangying; Zhang, Zhuqiang; Feng, Xue; Wang, Si; Cui, Xiuhong; Wang, Yanling; Gao, Fei; Hess, Rex A.; Han, Chunsheng

    2016-01-01

    The regulatory factor X (RFX) family of transcription factors is crucial for ciliogenesis throughout evolution. In mice, Rfx1-4 are highly expressed in the testis where flagellated sperm are produced, but the functions of these factors in spermatogenesis remain unknown. Here, we report the production and characterization of the Rfx2 knockout mice. The male knockout mice were sterile due to the arrest of spermatogenesis at an early round spermatid step. The Rfx2-null round spermatids detached from the seminiferous tubules, forming large multinucleated giant cells that underwent apoptosis. In the mutants, formation of the flagellum was inhibited at its earliest stage. RNA-seq analysis identified a large number of cilia-related genes and testis-specific genes that were regulated by RFX2. Many of these genes were direct targets of RFX2, as revealed by chromatin immunoprecipitation-PCR assays. These findings indicate that RFX2 is a key regulator of the post-meiotic development of mouse spermatogenic cells. PMID:26853561

  18. Key facts and hot spots on tumor necrosis factor receptor-associated periodic syndrome.

    PubMed

    Rigante, Donato; Lopalco, Giuseppe; Vitale, Antonio; Lucherini, Orso Maria; De Clemente, Caterina; Caso, Francesco; Emmi, Giacomo; Costa, Luisa; Silvestri, Elena; Andreozzi, Laura; Iannone, Florenzo; Galeazzi, Mauro; Cantarini, Luca

    2014-09-01

    Tumor necrosis factor receptor-associated periodic syndrome (TRAPS), formerly known as familial Hibernian fever, is the most common autosomal dominant autoinflammatory disease, resulting from mutations in the TNFRSF1A gene, encoding the 55-kD tumor necrosis factor receptor. The pathophysiologic mechanism of TRAPS remains ambiguous and only partially explained. The onset age of the syndrome is variable and the clinical scenery is characterized by recurrent episodes of high-grade fever that typically lasts 1-3 weeks, associated with migrating myalgia, pseudocellulitis, diffuse abdominal pain, appendicitis-like findings, ocular inflammatory signs, and risk of long-term amyloidosis. Fever episodes are responsive to high-dose corticosteroids, but different classes of drugs have been reported to be ineffective. The use of etanercept is unable to control systemic inflammation, while interleukin-1 blockade has been shown as effective in the control of disease activity in many patients reported so far. PMID:24935411

  19. The transcription factor Pokemon: a new key player in cancer pathogenesis.

    PubMed

    Maeda, Takahiro; Hobbs, Robin M; Pandolfi, Pier Paolo

    2005-10-01

    Learning how critical cell regulatory pathways are controlled may lead to new opportunities for cancer treatment. We recently identified the transcription factor Pokemon as a central regulator of the important tumor suppressor ARF. Pokemon is overexpressed in multiple human cancers and cells lacking Pokemon are refractory to oncogenic transformation. These findings suggest that Pokemon may offer an effective new target for cancer therapeutics. PMID:16204018

  20. Understanding key drivers controlling daily stable isotope variations in precipitation of Costa Rica, Central America

    NASA Astrophysics Data System (ADS)

    Sanchez-Murillo, Ricardo; Welsh, Kristin; Birkel, Christian; Esquivel-Hernández, Germain; Corrales-Salazar, Jose; Boll, Jan; Brooks, Erin; Roupsard, Olivier; Katchan, Irina; Arce-Mesén, Rafael; Soulsby, Chris; Araguás-Araguás, Luis

    2015-04-01

    Costa Rica is located on the Central American Isthmus, which receives direct moisture inputs from the Caribbean Sea and the Pacific Ocean. The relatively narrow, but high relief Central American land bridge is characterized by unique mountainous and lowland microclimates. However, only limited knowledge exists about the impact of relief and regional atmospheric circulation patterns on precipitation origin, transport, and isotopic composition in this tropical region. Therefore, the main scope of this study is to identify the key drivers controlling variations in meteoric waters of Costa Rica using stable isotopes based on daily sample collection for the year 2013. The monitoring sites comprise three strategic locations across Costa Rica: Heredia (Central Valley), Turrialba (Caribbean slope), and Caño Seco (South Pacific slope). Sporadic dry season rain is mostly related to isolated enriched events ranging from -5.8‰ d18O up to -0.9‰ d18O. By mid-May, the Intertropical Convergence Zone reaches Costa Rica resulting in a notable depletion in isotope ratios (up to -18.5‰ d18O). HYSPLIT back air mass trajectories indicate the strong influence on the origin and transport of precipitation of two main moisture transport mechanisms, the Caribbean Low Level Jet and the Colombian Low Level Jet as well as localized convection events. Multiple linear regression models constructed based on Random Forests of surface meteorological information and atmospheric sounding profiles suggest that Lifted Condensation Level and surface relative humidity are the main factors controlling isotopic variations. These findings diverge from the recognized 'amount effect' in monthly composite samples across the tropics. Understanding of stable isotope dynamics in tropical precipitation can be used to enhance catchment and groundwater modeling efforts in ungauged basins where scarcity of long-term monitoring data drastically limit current and future water resources management.

  1. Key factors influencing rates of heterotrophic sulfate reduction in hydrothermal massive sulfide deposits

    NASA Astrophysics Data System (ADS)

    Frank, K. L.; Rogers, D.; Girguis, P. R.

    2012-12-01

    Despite sulfate reduction's ubiquity in marine systems, relatively little is known about how environmental or ecological factors influence rates of sulfate reduction. While numerous studies have considered how sulfate reduction and methanogenesis compete for reductants in natural and human-made systems, less is known about how temperature or metabolite concentration, such as sulfate and sulfide concentrations, affects rates of sulfate reduction. Here we use a factorial experimental design to evaluate the effects of key variables on sulfate reduction kinetics in sulfide deposits recovered from hydrothermal vents in the Main Endeavor Field, Juan de Fuca ridge. Microbial sulfate reduction rates were measured by 35-S tracer techniques over a range of environmentally relevant chemical conditions (pH, H2S, SO42-, and organic carbon concentrations) and temperatures (4, 50 and 90°C). Maximum sulfate reduction rates were observed at 50°C, and sulfate reduction rates had significant positive correlations with increasing sulfide, pH and sulfate. However, sulfate reduction rates did not correlate to exogenous dissolved organic carbon, implicating exogenous hydrogen or endogenous organic matter as the reductant (or even sulfur disproportionation). This research presents an opportunity to better understand the key variables that influence the rates of microbial sulfate reduction in hydrothermal environments and provides a framework for modeling sulfate reduction in mid-ocean ridge systems.

  2. A Secure Three-Factor User Authentication and Key Agreement Protocol for TMIS With User Anonymity.

    PubMed

    Amin, Ruhul; Biswas, G P

    2015-08-01

    Telecare medical information system (TMIS) makes an efficient and convenient connection between patient(s)/user(s) and doctor(s) over the insecure internet. Therefore, data security, privacy and user authentication are enormously important for accessing important medical data over insecure communication. Recently, many user authentication protocols for TMIS have been proposed in the literature and it has been observed that most of the protocols cannot achieve complete security requirements. In this paper, we have scrutinized two (Mishra et al., Xu et al.) remote user authentication protocols using smart card and explained that both the protocols are suffering against several security weaknesses. We have then presented three-factor user authentication and key agreement protocol usable for TMIS, which fix the security pitfalls of the above mentioned schemes. The informal cryptanalysis makes certain that the proposed protocol provides well security protection on the relevant security attacks. Furthermore, the simulator AVISPA tool confirms that the protocol is secure against active and passive attacks including replay and man-in-the-middle attacks. The security functionalities and performance comparison analysis confirm that our protocol not only provide strong protection on security attacks, but it also achieves better complexities along with efficient login and password change phase as well as session key verification property. PMID:26112322

  3. A key factor to the spin parameter of uniformly rotating compact stars: crust structure

    NASA Astrophysics Data System (ADS)

    Qi, Bin; Zhang, Nai-Bo; Sun, Bao-Yuan; Wang, Shou-Yu; Gao, Jian-Hua

    2016-04-01

    We study the dimensionless spin parameter j ≡ cJ/(GM2) of different kinds of uniformly rotating compact stars, including traditional neutron stars, hyperonic neutron stars and hybrid stars, based on relativistic mean field theory and the MIT bag model. It is found that jmax ∼ 0.7, which had been suggested in traditional neutron stars, is sustained for hyperonic neutron stars and hybrid stars with M > 0.5 M⊙. Not the interior but rather the crust structure of the stars is a key factor to determine jmax for three kinds of selected compact stars. Furthermore, a universal formula j = 0.63(f/fK) ‑ 0.42(f/fK)2 + 0.48(f/fK)3 is suggested to determine the spin parameter at any rotational frequency f smaller than the Keplerian frequency fK.

  4. Traumatic Brain Injury as a Risk Factor for Alzheimer's Disease: Is Inflammatory Signaling a Key Player?

    PubMed

    Djordjevic, Jelena; Sabbir, Mohammad Golam; Albensi, Benedict C

    2016-01-01

    Traumatic brain injury (TBI) has become a significant medical and social concern within the last 30 years. TBI has acute devastating effects, and in many cases, seems to initiate long-term neurodegeneration. With advances in medical technology, many people are now surviving severe brain injuries and their long term consequences. Post trauma effects include communication problems, sensory deficits, emotional and behavioral problems, physical complications and pain, increased suicide risk, dementia, and an increased risk for chronic CNS diseases, such as Alzheimer's disease (AD). In this review, we provide an introduction to TBI and hypothesize how it may lead to neurodegenerative disease in general and AD in particular. In addition, we discuss the evidence that supports the hypothesis that TBI may lead to AD. In particular, we focus on inflammatory responses as key processes in TBI-induced secondary injury, with emphasis on nuclear factor kappa B (NF-κB) signaling. PMID:26899581

  5. Neisseria meningitidis factor H-binding protein fHbp: a key virulence factor and vaccine antigen.

    PubMed

    Seib, Kate L; Scarselli, Maria; Comanducci, Maurizio; Toneatto, Daniela; Masignani, Vega

    2015-06-01

    Neisseria meningitidis is a leading cause of meningitis and sepsis worldwide. The first broad-spectrum multicomponent vaccine against serogroup B meningococcus (MenB), 4CMenB (Bexsero(®)), was approved by the EMA in 2013, for prevention of MenB disease in all age groups, and by the US FDA in January 2015 for use in adolescents. A second protein-based MenB vaccine has also been approved in the USA for adolescents (rLP2086, Trumenba(®)). Both vaccines contain the lipoprotein factor H-binding protein (fHbp). Preclinical studies demonstrated that fHbp elicits a robust bactericidal antibody response that correlates with the amount of fHbp expressed on the bacterial surface. fHbp is able to selectively bind human factor H, the key regulator of the alternative complement pathway, and this has important implications both for meningococcal pathogenesis and for vaccine design. Here, we review the functional and structural properties of fHbp, the strategies that led to the design of the two fHbp-based vaccines and the data generated during clinical studies. PMID:25704037

  6. Research toward control of key pecan insect pests using biorational pesticides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Key pecan insect pests include the pecan weevil, Curculio caryae, black pecan aphid, Melanocallis caryaefoliae, and stink bugs. Alternative control tactics are needed for management of these pests in organic and conventional systems. Our objective was to evaluate the efficacy of several alternativ...

  7. Power-Factor Controllers: How Safe?

    NASA Technical Reports Server (NTRS)

    Long, K.; Christian, W.; Kovacik, J.; Grazyk, T.

    1985-01-01

    Potential safety problems with power-factor controllers (PFC's) evaluated. Based on study of PFCs in use with appliances, report recommends measures to prevent consumers from misapplying these energy saving devices. Device used on such appliances as refrigerators, sewing machines, pumps, hair dryers, and food processors. When misused, they fail to save energy and may cause damage.

  8. Socioeconomic Factors and Asthma Control in Children

    PubMed Central

    Cope, Shannon F.; Ungar, Wendy J.; Glazier, Richard H.

    2016-01-01

    Summary Objectives The objective of this study was to evaluate the association between socioeconomic factors and asthma control in children, as defined by the Canadian Pediatric Asthma Consensus Guidelines. Patients and Methods Cross-sectional data from a completed study of 879 asthmatic children between the ages of 1 and 18 residing in the Greater Toronto Area were used. The database included data on demographics, health status, asthma control, and health-related quality of life. Stepwise forward modeling multiple regression was used to investigate the impact of socioeconomic status on asthma control, based on six control parameters from the 2003 Canadian Pediatric Asthma Consensus Guidelines. Results Only 11% of patients met the requirements for acceptable control, while 20% had intermediate control, and 69% had unacceptable asthma control. Children from families in lower income adequacy levels had poorer control. Conclusions Disparities in asthma control between children from families of different socio-economic strata persist, even with adjustment for utilization of primary care services and use of controller medications. PMID:18615669

  9. Age at disease onset: a key factor for understanding psoriatic disease.

    PubMed

    Queiro, Rubén; Tejón, Patricia; Alonso, Sara; Coto, Pablo

    2014-07-01

    Psoriasis and PsA are immune-mediated diseases with a strong genetic component. More than 20 new loci have been recently linked to these diseases. However, interactions between these genes and the phenotypic traits of both diseases are poorly understood at present. Stratification of psoriatic disease according to the sex of the patients, genetic factors or age at onset has allowed in the last few years a better understanding of the principles governing the onset and progression of these processes. The age of onset of psoriasis has been used for decades as an appropriate descriptor to define two subpopulations of psoriatic patients (types I and II) whose clinical and immunogenetic characteristics have been very well differentiated. Moreover, in patients with PsA this distinction between type I and II psoriasis also seems equally operative. In patients with PsA expressing the HLA-C*06 antigen, the latency between the onset of psoriasis and onset of joint symptoms is longer than in those without this marker. It is also known that PsA tends to appear earlier in patients with HLA-B*27 positivity, and that these patients also show a shorter interval of time between the onset of cutaneous lesions and the onset of joint disease. This review highlights the growing importance of age at disease onset as a key stratification factor in worldwide clinical and genetic studies of psoriatic disease. PMID:24273020

  10. Organization of Anti-Phase Synchronization Pattern in Neural Networks: What are the Key Factors?

    PubMed Central

    Li, Dong; Zhou, Changsong

    2011-01-01

    Anti-phase oscillation has been widely observed in cortical neural network. Elucidating the mechanism underlying the organization of anti-phase pattern is of significance for better understanding more complicated pattern formations in brain networks. In dynamical systems theory, the organization of anti-phase oscillation pattern has usually been considered to relate to time delay in coupling. This is consistent to conduction delays in real neural networks in the brain due to finite propagation velocity of action potentials. However, other structural factors in cortical neural network, such as modular organization (connection density) and the coupling types (excitatory or inhibitory), could also play an important role. In this work, we investigate the anti-phase oscillation pattern organized on a two-module network of either neuronal cell model or neural mass model, and analyze the impact of the conduction delay times, the connection densities, and coupling types. Our results show that delay times and coupling types can play key roles in this organization. The connection densities may have an influence on the stability if an anti-phase pattern exists due to the other factors. Furthermore, we show that anti-phase synchronization of slow oscillations can be achieved with small delay times if there is interaction between slow and fast oscillations. These results are significant for further understanding more realistic spatiotemporal dynamics of cortico-cortical communications. PMID:22232576

  11. Ruguo key genes and tumor driving factors identification of bladder cancer based on the RNA-seq profile

    PubMed Central

    Zhang, Minglei; Li, Hongyan; Zou, Di; Gao, Ji

    2016-01-01

    Aim This study aimed to select several signature genes associated with bladder cancer, thus to investigate the possible mechanism in bladder cancer. Methods The mRNA expression profile data of GSE31614, including ten bladder tissues and ten control samples, was downloaded from the Gene Expression Omnibus. The differentially expressed genes (DEGs) in bladder cancer samples compared with the control samples were screened using the Student’s t-test method. Functional analysis for the DEGs was analyzed using the Database for Annotation, Visualization, and Integrated Discovery from the Gene Ontology database, followed by the transcription function annotation of DEGs from Tumor-Associated Gene database. Motifs of genes that had transcription functions in promoter region were analyzed using the Seqpos. Results A total of 1,571 upregulated and 1,507 downregulated DEGs in the bladder cancer samples were screened. ELF3 and MYBL2 involved in cell cycle and DNA replication were tumor suppressors. MEG3, APEX1, and EZH2 were related with the cell epigenetic regulation in bladder cancer. Moreover, HOXB9 and EN1 that have their own motif were the transcription factors. Conclusion Our study has identified several key genes involved in bladder cancer. ELF3 and MYBL2 are tumor suppressers, HOXB9 and EN1 are the main regulators, while MEG3, APEX1, and EZH2 are driving factors for bladder cancer progression. PMID:27217782

  12. Nutrient depletion as a key factor for manipulating gene expression and product formation in different branches of the flavonoid pathway.

    PubMed

    Lillo, Cathrine; Lea, Unni S; Ruoff, Peter

    2008-05-01

    The content of flavonoids increases in response to nitrogen and phosphorus depletion in plants. Manipulation of these macronutrients may therefore be used to control the levels of desirable compounds and improve plant quality. Key enzymes in the shikimate pathway, which feeds precursors into the flavonoid pathway, are regulated post-translationally by feedback from aromatic amino acids, and possibly by redox control through photosynthesis. Use of microarrays for global transcript analysis in Arabidopsis has revealed that transcript levels are less influenced by mineral nutrients in the shikimate pathway compared with the flavonoid pathway. The responses in the shikimate pathway appear complex, whereas in the flavonoid pathway, a single gene often responds similarly to mineral depletion, high light intensity and sucrose. MYB [production of anthocyanin pigment 1 (PAP1)/production of anthocyanin pigment 2 (PAP2)] and bHLH [GLABRA3 (GL3)] transcription factors are important for the nutrient depletion response. PAP1/2 stimulate gross activation of the flavonoid pathway, and different investigations support merging signal transduction chains for various abiotic treatments on PAP1/2. Flavonol synthase is not part of the PAP1/2 regulon, and expression is mainly enhanced by high light intensity and sucrose, not mineral depletion. Nevertheless, both cyanidin and flavonol derivatives increase in response to nitrogen depletion. Kaempferols are the dominating flavonols in Arabidopsis leaves under normal cultivation conditions, but quercetin accumulation can be triggered by nitrogen depletion in combination with other abiotic factors. PMID:18031469

  13. Key factors limiting the open circuit voltage of n(+)pp(+) indium phosphide solar cells

    NASA Technical Reports Server (NTRS)

    Goradia, Chandra; Thesling, William; Weinberg, Irving

    1990-01-01

    Solar cells made from gallium arsenide (Gaas), with a room temperature bandgap of E(sub g) = 1.43 eV have exhibited the best measured open circuit voltage (V sub oc) of 1.05 V at 1 AM0, 25 C. The material InP is in many ways similar to GaAs. A simple calculation comparing InP to GaAs then shows that solar cells made from InP, with E(sub g) = 1.35 at 300 K, should exhibit the best measured V sub oc of approximately 950 mV at 1 AM0, 300 K. However, to date, the best measured V sub oc for InP solar cells made by any fabrication method is 899 mV at AM1.5, 25 C which would translate to 912 mV at 1 AM0, 25 C. The V sub oc of an n(+)pp(+) InP solar cell is governed by several factors. Of these, some factors, such as the thickness and doping of the emitter and base regions, are easily controlled and can be adjusted to desired values dictated by a good performance optimizing model. Such factors were not considered. There are other factors which also govern V sub oc, and their values are not so easily controlled. The primary ones among these are (1) the indirect or Hall-Shockley-Read lifetimes in the various regions of the cell, (2) the low-doping intrinsic carrier concentration n(sub i) of the InP material, (3) the heavy doping factors in the emitter and BSF regions, and (4) the front surface recombination velocity S(sub F). The influence of these latter factors on the V sub oc of the n(+)pp(+) InP solar cell and the results were used to produce a near-optimum design of the n(+)pp(+) InP solar cell.

  14. Key factors limiting the open circuit voltage of n(+)pp(+) indium phosphide solar cells

    NASA Technical Reports Server (NTRS)

    Goradia, Chandra; Thesling, William; Weinberg, Irving

    1991-01-01

    Solar cells made from gallium arsenide (GaAs), with a room temperature bandgap of E(sub g) = 1.43 eV have exhibited the best measured open circuit voltage (V sub OC) of 1.05 V at 1 AMO, 25 C. The material InP is in many ways similar to GaAs. A simple calculation comparing InP to GaAs then shows that solar cells made from InP, with E(sub g) = 1.35 at 300 K, should exhibit the best measured (V sub OC) of approximately 950 mV at 1 AMO, 300 K. However, to date, the best measured V(sub OC) for InP solar cells made by any fabrication method is 899 mV at AM1.5, 25 C which would translate to 912 mV at 1 AMO, 25 C. The V(sub OC) of an n(+)pp(+) InP solar cell is governed by several factors. Of these, some factors, such as the thickness and doping of the emitter and base regions, are easily controlled and can be adjusted to desired values dictated by a good performance optimizing model. Such factors were not considered. There are other factors which also govern V(sub OC), and their values are not so easily controlled. The primary ones among these are (1) the indirect or Hall-Shockley-Read lifetimes in the various regions of the cell, (2) the low-doping intrinsic carrier concentration n(sub i) of the InP material, (3) the heavy doping factors in the emitter and BSF regions, and (4) the front surface recombination velocity S(sub F). The influence of these latter factors on the V(sub OC) of the n(+)pp(+) InP solar cell and the results were used to produce a near-optimum design of the n(+)pp(+) InP solar cell.

  15. Defining a protective epitope on factor H binding protein, a key meningococcal virulence factor and vaccine antigen.

    PubMed

    Malito, Enrico; Faleri, Agnese; Lo Surdo, Paola; Veggi, Daniele; Maruggi, Giulietta; Grassi, Eva; Cartocci, Elena; Bertoldi, Isabella; Genovese, Alessia; Santini, Laura; Romagnoli, Giacomo; Borgogni, Erica; Brier, Sébastien; Lo Passo, Carla; Domina, Maria; Castellino, Flora; Felici, Franco; van der Veen, Stijn; Johnson, Steven; Lea, Susan M; Tang, Christoph M; Pizza, Mariagrazia; Savino, Silvana; Norais, Nathalie; Rappuoli, Rino; Bottomley, Matthew J; Masignani, Vega

    2013-02-26

    Mapping of epitopes recognized by functional monoclonal antibodies (mAbs) is essential for understanding the nature of immune responses and designing improved vaccines, therapeutics, and diagnostics. In recent years, identification of B-cell epitopes targeted by neutralizing antibodies has facilitated the design of peptide-based vaccines against highly variable pathogens like HIV, respiratory syncytial virus, and Helicobacter pylori; however, none of these products has yet progressed into clinical stages. Linear epitopes identified by conventional mapping techniques only partially reflect the immunogenic properties of the epitope in its natural conformation, thus limiting the success of this approach. To investigate antigen-antibody interactions and assess the potential of the most common epitope mapping techniques, we generated a series of mAbs against factor H binding protein (fHbp), a key virulence factor and vaccine antigen of Neisseria meningitidis. The interaction of fHbp with the bactericidal mAb 12C1 was studied by various epitope mapping methods. Although a 12-residue epitope in the C terminus of fHbp was identified by both Peptide Scanning and Phage Display Library screening, other approaches, such as hydrogen/deuterium exchange mass spectrometry (MS) and X-ray crystallography, showed that mAb 12C1 occupies an area of ∼1,000 Å(2) on fHbp, including >20 fHbp residues distributed on both N- and C-terminal domains. Collectively, these data show that linear epitope mapping techniques provide useful but incomplete descriptions of B-cell epitopes, indicating that increased efforts to fully characterize antigen-antibody interfaces are required to understand and design effective immunogens. PMID:23396847

  16. Hepatitis C virus suppresses Hepatocyte Nuclear Factor 4 alpha, a key regulator of hepatocellular carcinoma.

    PubMed

    Vallianou, Ioanna; Dafou, Dimitra; Vassilaki, Niki; Mavromara, Penelope; Hadzopoulou-Cladaras, Margarita

    2016-09-01

    Hepatitis C Virus (HCV) infection presents with a disturbed lipid profile and can evolve to hepatic steatosis and hepatocellular carcinoma (HCC). Hepatocyte Nuclear Factor 4 alpha (HNF4α) is the most abundant transcription factor in the liver, a key regulator of hepatic lipid metabolism and a critical determinant of Epithelial to Mesenchymal Transition and hepatic development. We have previously shown that transient inhibition of HNF4α initiates transformation of immortalized hepatocytes through a feedback loop consisting of miR-24, IL6 receptor (IL6R), STAT3, miR-124 and miR-629, suggesting a central role of HNF4α in HCC. However, the role of HNF4α in Hepatitis C Virus (HCV)-related hepatocarcinoma has not been evaluated and remains controversial. In this study, we provide strong evidence suggesting that HCV downregulates HNF4α expression at both transcriptional and translational levels. The observed decrease of HNF4α expression correlated with the downregulation of its downstream targets, HNF1α and MTP. Ectopic overexpression of HCV proteins also exhibited an inhibitory effect on HNF4α levels. The inhibition of HNF4α expression by HCV appeared to be mediated at transcriptional level as HCV proteins suppressed HNF4α gene promoter activity. HCV also up-regulated IL6R, activated STAT3 protein phosphorylation and altered the expression of acute phase genes. Furthermore, as HCV triggered the loss of HNF4α a consequent change of miR-24, miR-629 or miR-124 was observed. Our findings demonstrated that HCV-related HCC could be mediated through HNF4α-microRNA deregulation implying a possible role of HNF4α in HCV hepatocarcinogenesis. HCV inhibition of HNF4α could be sustained to promote HCC. PMID:27477312

  17. Corticotropin-releasing factor: a possible key to gut dysfunction in the critically ill.

    PubMed

    Hill, Lauren T; Kidson, Susan H; Michell, William L

    2013-01-01

    Critically ill patients frequently display unexplained or incompletely explained features of gastrointestinal (GI) dysfunction, including gastric stasis, ileus, and diarrhea. This makes nutrition delivery challenging, and may contribute to poor outcomes. The typical bowel dysfunction seen in severely ill patients includes retarded gastric emptying, unsynchronized intestinal motility, and intestinal hyperpermeability. These functional changes appear similar to the corticotropin-releasing factor (CRF)-mediated bowel dysfunctions associated with stress of various types and some GI disorders and diseases. CRF has been shown to be present within the GI tract and its action on CRF receptors within the gut have been shown to reduce gastric emptying, alter intestinal motility, and increase intestinal permeability. However, the precise role of CRF in the GI dysfunction in critical illness remains unclear. In this short review, we provide an update on GI dysfunction during stress and review the possible role of CRF in the aetiology of gut dysfunction. We suggest that activation of CRF signaling pathways in critical illness might be key to understanding the mechanisms underlying the gut dysfunction that impairs enteral feeding in the intensive care unit. PMID:23484741

  18. Prosthetic Abutment Height is a Key Factor in Peri-implant Marginal Bone Loss

    PubMed Central

    Galindo-Moreno, P.; León-Cano, A.; Ortega-Oller, I.; Monje, A.; Suárez, F.; ÓValle, F.; Spinato, S.; Catena, A.

    2014-01-01

    In this study, we analyzed the influence of prosthetic abutment height on marginal bone loss (MBL) around implants in the posterior maxilla. In this retrospective cohort study, the radiographically determined MBL was related to the height of the abutments of internal conical connection implants at 6 and 18 months post-loading. Data were gathered on age, sex, bone substratum, smoking habit, history of periodontitis, and prosthetic features, among other variables. A linear mixed model was used for statistical analysis. The study included 131 patients receiving 315 implants. MBL rates at 6 and 18 months were mainly affected by the abutment height but were also significantly influenced by the bone substratum, periodontitis, and smoking habit. MBL rates were higher for prosthetic abutment < 2 mm vs. ≥ 2 mm, for periodontal vs. non-periodontal patients, for grafted vs. pristine bone, and for a heavier smoking habit. The abutment height is a key factor in MBL. MBL rates followed a non-linear trend, with a greater MBL rate during the first 6 months post-loading than during the next 12 months. PMID:24621670

  19. Molecular mobility of imidazoles in molten state as a key factor to enhance proton conductivity

    NASA Astrophysics Data System (ADS)

    Jarumaneeroj, Chatchai; Tashiro, Kohji; Chirachanchai, Suwabun

    2014-03-01

    A systematic study on alkyl urocanates related to the proton conductivity performances to clarify the role of molecular mobility and hydrogen bond in proton transfer is carried out. Depending on the methylene units, the melting (Tm) and degradation temperatures (Td) change remarkably. When methylene unit is four, C4U shows the lowest melting point (as low as 46 °C) and this suggests the favorable molecular mobility in the molten state. The short hydrogen bond distance and the short T1 relaxation time lead to a scheme of proton conductivity of C4U to be under a regular imidazole arrangement with highly active alkyl chain molecular motion. When C4U is in molten state, the proton transfer is under vehicle mechanism clarified by Volgel-Tammann-Fulcher (VTF) equation. By applying C4U as a proton conductive additive in a sulfonated poly(ether ether ketone) (SPEEK) membrane without any acid dopants, the proton conductivity in the heating process up to 170 °C continuously increases to be ∼104 times higher than that of the neat SPEEK. The present work not only demonstrates the thermal mobility as a key factor to govern the proton conductivity but also proposes the effective proton transfer of heterocyclic compounds based on the molten state.

  20. On Key Factors Influencing Ductile Fractures of Dual Phase (DP) Steels

    SciTech Connect

    Sun, Xin; Choi, Kyoo Sil; Soulami, Ayoub; Liu, Wenning N.; Khaleel, Mohammad A.

    2009-11-25

    In this paper, we examine the key factors influencing ductile failure of various grades of dual phase (DP) steels using the microstructure-based modeling approach. Various microstructure-based finite element models are generated based on the actual microstructures of DP steels with different martensite volume fractions. These models are, then, used to investigate the influence of ductility of the constituent ferrite phase and also the influence of voids introduced in the ferrite phase on the overall ductility of DP steels. It is found that with volume fraction of martensite in the microstructure less than 15%, the overall ductility of the DP steels strongly depends on the ductility of the ferrite matrix, hence pre-existing micro voids in the microstructure significantly reduce the overall ductility of the steel. When the volume fraction of martensite is above 15%, the preexisting voids in the ferrite matrix does not significantly reduce the overall ductility of the DP steels, and the overall ductility is more influenced by the mechanical property disparity between the two phases. The applicability of the phase inhomogeneity driven ductile failure of DP steels is then discussed based on the obtained computational results for various grades of DP steels, and the experimentally obtained scanning electron microscopy (SEM) pictures of the corresponding grades of DP steels near fracture surface are used as evidence for result validations.

  1. Process and kinetics of azo dye decolourization in bioelectrochemical systems: effect of several key factors.

    PubMed

    Yang, Hou-Yun; He, Chuan-Shu; Li, Lei; Zhang, Jie; Shen, Jin-You; Mu, Yang; Yu, Han-Qing

    2016-01-01

    This study explored the influence of several key factors on the process and kinetics of azo dye decolourization in bioelectrochemical systems (BESs), including cathode potential, dissolved oxygen (DO) concentration of catholyte and biofilm formed on the cathode. The results show that azo dye methyl orange (MO) decolourization in the BES could be well described with the pseudo first-order kinetics. The MO decolourization efficiency increased from 0 to 94.90 ± 0.01% and correspondingly the reaction rate constant increased from 0 to 0.503 ± 0.001 h(-1) with the decrease in cathodic electrode potential from -0.2 to -0.8 V vs Ag/AgCl. On the contrary, DO concentration of the catholyte had a negative impact on MO decolourization in the BES. When DO concentration increased from zero to 5.80 mg L(-1), the MO decolourization efficiency decreased from 87.19 ± 4.73% to 27.77 ± 0.06% and correspondingly the reaction rate constant reduced from 0.207 ± 0.042 to 0.033 ± 0.007 h(-1). Additionally, the results suggest that the biofilm formed on the cathode could led to an adverse rather than a positive effect on azo dye decolourization in the BES in terms of efficiency and kinetics. PMID:27270398

  2. Therapeutic angiogenesis: controlled delivery of angiogenic factors

    PubMed Central

    Chu, Hunghao; Wang, Yadong

    2013-01-01

    Therapeutic angiogenesis aims at treating ischemic diseases by generating new blood vessels from existing vasculature. It relies on delivery of exogenous factors to stimulate neovasculature formation. Current strategies using genes, proteins and cells have demonstrated efficacy in animal models. However, clinical translation of any of the three approaches has proved to be challenging for various reasons. Administration of angiogenic factors is generally considered safe, according to accumulated trials, and offers off-the-shelf availability. However, many hurdles must be overcome before therapeutic angiogenesis can become a true human therapy. This article will highlight protein-based therapeutic angiogenesis, concisely review recent progress and examine critical challenges. We will discuss growth factors that have been widely utilized in promoting angiogenesis and compare their targets and functions. Lastly, since bolus injection of free proteins usually result in poor outcomes, we will focus on controlled release of proteins. PMID:22838066

  3. Key Factors in the Success of an Organization's Information Security Culture: A Quantitative Study and Analysis

    ERIC Educational Resources Information Center

    Pierce, Robert E.

    2012-01-01

    This research study reviewed relative literature on information security and information security culture within organizations to determine what factors potentially assist an organization in implementing, integrating, and maintaining a successful organizational information security culture. Based on this review of literature, five key factors were…

  4. Translational control of regA, a key gene controlling cell differentiation in Volvox carteri.

    PubMed

    Babinger, Karin; Hallmann, Armin; Schmitt, Rüdiger

    2006-10-01

    The complete division of labour between the reproductive and somatic cells of the green alga Volvox carteri is controlled by three types of genes. One of these is the regA gene, which controls terminal differentiation of the somatic cells. Here, we examined translational control elements located in the 5' UTR of regA, particularly the eight upstream start codons (AUGs) that have to be bypassed by the translation machinery before regA can be translated. The results of our systematic mutational, structural and functional analysis of the 5' UTR led us to conclude that a ribosome-shunting mechanism--rather than leaky scanning, ribosomal reinitiation, or internal ribosome entry site (IRES)-mediated initiation--controls the translation of regA mRNA. This mechanism, which involves dissociation of the 40S initiation complex from the message, followed by reattachment downstream, in order to bypass a secondary structure block in the mRNA, was validated by deleting the predicted ;landing site' (which prevented regA expression) and inserting a stable 64 nucleotide hairpin just upstream of this site (which did not prevent regA expression). We believe that this is the first report suggesting that translation of an mRNA in a green eukaryote is controlled by ribosome shunting. PMID:16971469

  5. Dominant factors in controlling marine gas pools in South China

    USGS Publications Warehouse

    Xu, S.; Watney, W.L.

    2007-01-01

    In marine strata from Sinian to Middle Triassic in South China, there develop four sets of regional and six sets of local source rocks, and ten sets of reservoir rocks. The occurrence of four main formation periods in association with five main reconstruction periods, results in a secondary origin for the most marine gas pools in South China. To improve the understanding of marine gas pools in South China with severely deformed geological background, the dominant control factors are discussed in this paper. The fluid sources, including the gas cracked from crude oil, the gas dissolved in water, the gas of inorganic origin, hydrocarbons generated during the second phase, and the mixed pool fluid source, were the most significant control factors of the types and the development stage of pools. The period of the pool formation and the reconstruction controlled the pool evolution and the distribution on a regional scale. Owing to the multiple periods of the pool formation and the reconstruction, the distribution of marine gas pools was complex both in space and in time, and the gas in the pools is heterogeneous. Pool elements, such as preservation conditions, traps and migration paths, and reservoir rocks and facies, also served as important control factors to marine gas pools in South China. Especially, the preservation conditions played a key role in maintaining marine oil and gas accumulations on a regional or local scale. According to several dominant control factors of a pool, the pool-controlling model can be constructed. As an example, the pool-controlling model of Sinian gas pool in Weiyuan gas field in Sichuan basin was summed up. ?? Higher Education Press and Springer-Verlag 2007.

  6. Environmental impact and risk assessments and key factors contributing to the overall uncertainties.

    PubMed

    Salbu, Brit

    2016-01-01

    , ignoring sensitive history life stages of organisms and transgenerational effects. To link sources, ecosystem transfer and biological effects to future impact and risks, a series of models are usually interfaced, while uncertainty estimates are seldom given. The model predictions are, however, only valid within the boundaries of the overall uncertainties. Furthermore, the model predictions are only useful and relevant when uncertainties are estimated, communicated and understood. Among key factors contributing most to uncertainties, the present paper focuses especially on structure uncertainties (model bias or discrepancies) as aspects such as particle releases, ecosystem dynamics, mixed exposure, sensitive life history stages and transgenerational effects, are usually ignored in assessment models. Research focus on these aspects should significantly reduce the overall uncertainties in the impact and risk assessment of radioactive contaminated ecosystems. PMID:26546475

  7. Granuloma Encapsulation Is a Key Factor for Containing Tuberculosis Infection in Minipigs

    PubMed Central

    Vilaplana, Cristina; Tapia, Gustavo; Díaz, Jorge; Fort, María; Cáceres, Neus; Pinto, Sergio; Caylà, Joan; Corner, Leigh; Domingo, Mariano; Cardona, Pere-Joan

    2010-01-01

    A transthoracic infection involving a low dose of Mycobacterium tuberculosis has been used to establish a new model of infection in minipigs. The 20-week monitoring period showed a marked Th1 response and poor humoral response for the whole infection. A detailed histopathological analysis was performed after slicing the formalin-fixed whole lungs of each animal. All lesions were recorded and classified according to their microscopic aspect, their relationship with the intralobular connective network and their degree of maturity in order to obtain a dissemination ratio (DR) between recent and old lesions. CFU counts and evolution of the DR with time showed that the proposed model correlated with a contained infection, decreasing from week 9 onwards. These findings suggest that the infection induces an initial Th1 response, which is followed by local fibrosis and encapsulation of the granulomas, thereby decreasing the onset of new lesions. Two therapeutic strategies were applied in order to understand how they could influence the model. Thus, chemotherapy with isoniazid alone helped to decrease the total number of lesions, despite the increase in DR after week 9, with similar kinetics to those of the control group, whereas addition of a therapeutic M. tuberculosis fragment-based vaccine after chemotherapy increased the Th1 and humoral responses, as well as the number of lesions, but decreased the DR. By providing a local pulmonary structure similar to that in humans, the mini-pig model highlights new aspects that could be key to a better understanding tuberculosis infection control in humans. PMID:20386605

  8. Hyperosmotic stress regulates the distribution and stability of myocardin-related transcription factor, a key modulator of the cytoskeleton.

    PubMed

    Ly, Donald L; Waheed, Faiza; Lodyga, Monika; Speight, Pam; Masszi, András; Nakano, Hiroyasu; Hersom, Maria; Pedersen, Stine F; Szászi, Katalin; Kapus, András

    2013-01-15

    Hyperosmotic stress initiates several adaptive responses, including the remodeling of the cytoskeleton. Besides maintaining structural integrity, the cytoskeleton has emerged as an important regulator of gene transcription. Myocardin-related transcription factor (MRTF), an actin-regulated coactivator of serum response factor, is a major link between the actin skeleton and transcriptional control. We therefore investigated whether MRTF is regulated by hyperosmotic stress. Here we show that hypertonicity induces robust, rapid, and transient translocation of MRTF from the cytosol to the nucleus in kidney tubular cells. We found that the hyperosmolarity-triggered MRTF translocation is mediated by the RhoA/Rho kinase (ROK) pathway. Moreover, the Rho guanine nucleotide exchange factor GEF-H1 is activated by hyperosmotic stress, and it is a key contributor to the ensuing RhoA activation and MRTF translocation, since siRNA-mediated GEF-H1 downregulation suppresses these responses. While the osmotically induced RhoA activation promotes nuclear MRTF accumulation, the concomitant activation of p38 MAP kinase mitigates this effect. Moderate hyperosmotic stress (600 mosM) drives MRTF-dependent transcription through the cis-element CArG box. Silencing or pharmacological inhibition of MRTF prevents the osmotic stimulation of CArG-dependent transcription and renders the cells susceptible to osmotic shock-induced structural damage. Interestingly, strong hyperosmolarity promotes proteasomal degradation of MRTF, concomitant with apoptosis. Thus, MRTF is an osmosensitive and osmoprotective transcription factor, whose intracellular distribution is regulated by the GEF-H1/RhoA/ROK and p38 pathways. However, strong osmotic stress destabilizes MRTF, concomitant with apoptosis, implying that hyperosmotically induced cell death takes precedence over epithelial-myofibroblast transition, a potential consequence of MRTF-mediated phenotypic reprogramming. PMID:23054059

  9. Occupancy by key transcription factors is a more accurate predictor of enhancer activity than histone modifications or chromatin accessibility

    SciTech Connect

    Dogan, Nergiz; Wu, Weisheng; Morrissey, Christapher S.; Chen, Kuan-Bei; Stonestrom, Aaron; Long, Maria; Keller, Cheryl A.; Cheng, Yong; Jain, Deepti; Visel, Axel; Pennacchio, Len A.; Weiss, Mitchell J.; Blobel, Gerd A.; Hardison, Ross C.

    2015-04-23

    Regulated gene expression controls organismal development, and variation in regulatory patterns has been implicated in complex traits. Thus accurate prediction of enhancers is important for further understanding of these processes. Genome-wide measurement of epigenetic features, such as histone modifications and occupancy by transcription factors, is improving enhancer predictions, but the contribution of these features to prediction accuracy is not known. Given the importance of the hematopoietic transcription factor TAL1 for erythroid gene activation, we predicted candidate enhancers based on genomic occupancy by TAL1 and measured their activity. Contributions of multiple features to enhancer prediction were evaluated based on the results of these and other studies. Results: TAL1-bound DNA segments were active enhancers at a high rate both in transient transfections of cultured cells (39 of 79, or 56%) and transgenic mice (43 of 66, or 65%). The level of binding signal for TAL1 or GATA1 did not help distinguish TAL1-bound DNA segments as active versus inactive enhancers, nor did the density of regulation-related histone modifications. A meta-analysis of results from this and other studies (273 tested predicted enhancers) showed that the presence of TAL1, GATA1, EP300, SMAD1, H3K4 methylation, H3K27ac, and CAGE tags at DNase hypersensitive sites gave the most accurate predictors of enhancer activity, with a success rate over 80% and a median threefold increase in activity. Chromatin accessibility assays and the histone modifications H3K4me1 and H3K27ac were sensitive for finding enhancers, but they have high false positive rates unless transcription factor occupancy is also included. Conclusions: Occupancy by key transcription factors such as TAL1, GATA1, SMAD1, and EP300, along with evidence of transcription, improves the accuracy of enhancer predictions based on epigenetic features.

  10. Occupancy by key transcription factors is a more accurate predictor of enhancer activity than histone modifications or chromatin accessibility

    DOE PAGESBeta

    Dogan, Nergiz; Wu, Weisheng; Morrissey, Christapher S.; Chen, Kuan-Bei; Stonestrom, Aaron; Long, Maria; Keller, Cheryl A.; Cheng, Yong; Jain, Deepti; Visel, Axel; et al

    2015-04-23

    Regulated gene expression controls organismal development, and variation in regulatory patterns has been implicated in complex traits. Thus accurate prediction of enhancers is important for further understanding of these processes. Genome-wide measurement of epigenetic features, such as histone modifications and occupancy by transcription factors, is improving enhancer predictions, but the contribution of these features to prediction accuracy is not known. Given the importance of the hematopoietic transcription factor TAL1 for erythroid gene activation, we predicted candidate enhancers based on genomic occupancy by TAL1 and measured their activity. Contributions of multiple features to enhancer prediction were evaluated based on the resultsmore » of these and other studies. Results: TAL1-bound DNA segments were active enhancers at a high rate both in transient transfections of cultured cells (39 of 79, or 56%) and transgenic mice (43 of 66, or 65%). The level of binding signal for TAL1 or GATA1 did not help distinguish TAL1-bound DNA segments as active versus inactive enhancers, nor did the density of regulation-related histone modifications. A meta-analysis of results from this and other studies (273 tested predicted enhancers) showed that the presence of TAL1, GATA1, EP300, SMAD1, H3K4 methylation, H3K27ac, and CAGE tags at DNase hypersensitive sites gave the most accurate predictors of enhancer activity, with a success rate over 80% and a median threefold increase in activity. Chromatin accessibility assays and the histone modifications H3K4me1 and H3K27ac were sensitive for finding enhancers, but they have high false positive rates unless transcription factor occupancy is also included. Conclusions: Occupancy by key transcription factors such as TAL1, GATA1, SMAD1, and EP300, along with evidence of transcription, improves the accuracy of enhancer predictions based on epigenetic features.« less

  11. Hyperosmotic stress regulates the distribution and stability of myocardin-related transcription factor, a key modulator of the cytoskeleton

    PubMed Central

    Ly, Donald L.; Waheed, Faiza; Lodyga, Monika; Speight, Pam; Masszi, András; Nakano, Hiroyasu; Hersom, Maria; Pedersen, Stine F.; Szászi, Katalin

    2013-01-01

    Hyperosmotic stress initiates several adaptive responses, including the remodeling of the cytoskeleton. Besides maintaining structural integrity, the cytoskeleton has emerged as an important regulator of gene transcription. Myocardin-related transcription factor (MRTF), an actin-regulated coactivator of serum response factor, is a major link between the actin skeleton and transcriptional control. We therefore investigated whether MRTF is regulated by hyperosmotic stress. Here we show that hypertonicity induces robust, rapid, and transient translocation of MRTF from the cytosol to the nucleus in kidney tubular cells. We found that the hyperosmolarity-triggered MRTF translocation is mediated by the RhoA/Rho kinase (ROK) pathway. Moreover, the Rho guanine nucleotide exchange factor GEF-H1 is activated by hyperosmotic stress, and it is a key contributor to the ensuing RhoA activation and MRTF translocation, since siRNA-mediated GEF-H1 downregulation suppresses these responses. While the osmotically induced RhoA activation promotes nuclear MRTF accumulation, the concomitant activation of p38 MAP kinase mitigates this effect. Moderate hyperosmotic stress (600 mosM) drives MRTF-dependent transcription through the cis-element CArG box. Silencing or pharmacological inhibition of MRTF prevents the osmotic stimulation of CArG-dependent transcription and renders the cells susceptible to osmotic shock-induced structural damage. Interestingly, strong hyperosmolarity promotes proteasomal degradation of MRTF, concomitant with apoptosis. Thus, MRTF is an osmosensitive and osmoprotective transcription factor, whose intracellular distribution is regulated by the GEF-H1/RhoA/ROK and p38 pathways. However, strong osmotic stress destabilizes MRTF, concomitant with apoptosis, implying that hyperosmotically induced cell death takes precedence over epithelial-myofibroblast transition, a potential consequence of MRTF-mediated phenotypic reprogramming. PMID:23054059

  12. Process and kinetics of azo dye decolourization in bioelectrochemical systems: effect of several key factors

    PubMed Central

    Yang, Hou-Yun; He, Chuan-Shu; Li, Lei; Zhang, Jie; Shen, Jin-You; Mu, Yang; Yu, Han-Qing

    2016-01-01

    This study explored the influence of several key factors on the process and kinetics of azo dye decolourization in bioelectrochemical systems (BESs), including cathode potential, dissolved oxygen (DO) concentration of catholyte and biofilm formed on the cathode. The results show that azo dye methyl orange (MO) decolourization in the BES could be well described with the pseudo first-order kinetics. The MO decolourization efficiency increased from 0 to 94.90 ± 0.01% and correspondingly the reaction rate constant increased from 0 to 0.503 ± 0.001 h−1 with the decrease in cathodic electrode potential from −0.2 to −0.8 V vs Ag/AgCl. On the contrary, DO concentration of the catholyte had a negative impact on MO decolourization in the BES. When DO concentration increased from zero to 5.80 mg L−1, the MO decolourization efficiency decreased from 87.19 ± 4.73% to 27.77 ± 0.06% and correspondingly the reaction rate constant reduced from 0.207 ± 0.042 to 0.033 ± 0.007 h−1. Additionally, the results suggest that the biofilm formed on the cathode could led to an adverse rather than a positive effect on azo dye decolourization in the BES in terms of efficiency and kinetics. PMID:27270398

  13. Identification of key transcription factors in caerulein-induced pancreatitis through expression profiling data.

    PubMed

    Qi, Dachuan; Wu, Bo; Tong, Danian; Pan, Ye; Chen, Wei

    2015-08-01

    The current study aimed to isolate key transcription factors (TFs) in caerulein-induced pancreatitis, and to identify the difference between wild type and Mist1 knockout (KO) mice, in order to elucidate the contribution of Mist1 to pancreatitis. The gene profile of GSE3644 was downloaded from the Gene Expression Omnibus database then analyzed using the t-test. The isolated differentially expressed genes (DEGs) were mapped into a transcriptional regulatory network derived from the Integrated Transcription Factor Platform database and in the network, the interaction pairs involving at least one DEG were screened. Fisher's exact test was used to analyze the functional enrichment of the target genes. A total of 1,555 and 3,057 DEGs were identified in the wild type and Mist1KO mice treated with caerulein, respectively. DEGs screened in Mist1KO mice were predominantly enriched in apoptosis, mitogen-activated protein kinase signaling and other cancer-associated pathways. A total of 188 and 51 TFs associated with pathopoiesis were isolated in Mist1KO and wild type mice, respectively. Out of the top 10 TFs (ranked by P-value), 7 TFs, including S-phase kinase-associated protein 2 (Skp2); minichromosome maintenance complex component 3 (Mcm3); cell division cycle 6 (Cdc6); cyclin B1 (Ccnb1); mutS homolog 6 (Msh6); cyclin A2 (Ccna2); and cyclin B2 (Ccnb2), were expressed in the two types of mouse. These TFs were predominantly involved in phosphorylation, DNA replication, cell division and DNA mismatch repair. In addition, specific TFs, including minichromosome maintenance complex component 7 (Mcm7); lymphoid-specific helicase (Hells); and minichromosome maintenance complex component 6 (Mcm6), that function in the unwinding of DNA were identified to participate in Mist1KO pancreatitis. The DEGs, including Cdc6, Mcm6, Msh6 and Wdr1 are closely associated with the regulation of caerulein-induced pancreatitis. Furthermore, other identified TFs were also involved in this type of

  14. Soil physical properties: Key factors for successful reclamation of disturbed landscapes

    NASA Astrophysics Data System (ADS)

    Krümmelbein, Julia; Raab, Thomas

    2013-04-01

    The practice of open cast mining, e.g. for lignite, results in major landscape disturbances and especially affects soils because relocation and subsequent mixing of naturally developed soil horizons leads to areas with extremely altered soil properties compared to the undisturbed conditions. Various reclamation measures are applied to recover the reconstructed landscape for different land use options. Major parts of the post mining landscapes are used for agriculture, agroforestry or silviculture, the remaining voids of the coal mines fill successively with groundwater after mine closure and are or will be used mainly for touristic and leisure purposes. Small proportions of the post mining areas are left for natural succession, or habitats for endangered flora and fauna are initiated. In reclamation research, many studies have focused on soil chemical and biological constraints of post mining substrates and investigated factors such as unsuitable pH, in many cases very low pH, (poor) nutrient contents and (poor) biological activity. But the initial and developing soil physical parameters and functions are also key factors for the success of reclamation practices. The soil water and gas balance influence strongly the suitability of a site for the intended future land use. The mechanical stability of the soil determines the rigidity of the pore system against deforming forces and thereby the persistence of soil functions, such as water and air permeability over time. The amendment of unfavourable (initial) soil physical properties is in most cases more complex and time-consuming than e.g. optimization of pH or fertilization with nutrients. Moreover, regarding the suitability of a site e.g. as a habitat for plants or microorganisms, poor physical pre-conditions can turn substrates with perfect nutrient contents and composition and pH into infertile locations of very low productivity. We show results of an on-going field study where the effects of different

  15. Corticotropin Releasing Factor: A Key Role in the Neurobiology of Addiction

    PubMed Central

    Zorrilla, Eric P.; Logrip, Marian L.; Koob, George F.

    2014-01-01

    Drug addiction is a chronically relapsing disorder characterized by loss of control over intake and dysregulation of stress-related brain emotional systems. Since the discovery by Wylie Vale and his colleagues of corticotropin-releasing factor (CRF) and the structurally-related urocortins, CRF systems have emerged as mediators of the body’s response to stress. Relatedly, CRF systems have a prominent role in driving addiction via actions in the central extended amygdala, producing anxiety-like behavior, reward deficits, excessive, compulsive-like drug self-administration and stress-induced reinstatement of drug seeking. CRF neuron activation in the medial prefrontal cortex may also contribute to the loss of control. Polymorphisms in CRF system molecules are associated with drug use phenotypes in humans, often in interaction with stress history. Drug discovery efforts have yielded brain-penetrant CRF1 antagonists with activity in preclinical models of addiction.. The results support the hypothesis that brain CRF-CRF1 systems contribute to the etiology and maintenance of addiction. PMID:24456850

  16. Leptin in early life: a key factor for the development of the adult metabolic profile.

    PubMed

    Granado, Miriam; Fuente-Martín, Esther; García-Cáceres, Cristina; Argente, Jesús; Chowen, Julie A

    2012-01-01

    Leptin levels during the perinatal period are important for the development of metabolic systems involved in energy homeostasis. In rodents, there is a postnatal leptin surge, with circulating leptin levels increasing around postnatal day (PND) 5 and peaking between PND 9 and PND 10. At this time circulating leptin acts as an important trophic factor for the development of hypothalamic circuits that control energy homeostasis and food seeking and reward behaviors. Blunting the postnatal leptin surge results in long-term leptin insensitivity and increased susceptibility to diet-induced obesity during adulthood. Pharmacologically increased leptin levels in the postnatal period also have long-term effects on metabolism. Nevertheless, this effect is controversial as postnatal hyperleptinemia is reported to both increase and decrease the predisposition to obesity in adulthood. The different effects reported in the literature could be explained by the different moments at which this hormone was administered, suggesting that modifications of the neonatal leptin surge at specific time points could selectively affect the development of central and peripheral systems that are undergoing modifications at this moment resulting in different metabolic and behavioral outcomes. In addition, maternal nutrition and the hormonal environment during pregnancy and lactation may also modulate the offspring's response to postnatal modifications in leptin levels. This review highlights the importance of leptin levels during the perinatal period in the development of metabolic systems that control energy homeostasis and how modifications of these levels may induce long-lasting and potentially irreversible effects on metabolism. PMID:22433625

  17. Some Factors in Children's Identification of Key Words in Written Passages.

    ERIC Educational Resources Information Center

    Bruning, Roger; Kennedy, Dale

    For this study of children's selection of key words, children in the first, third, sixth, ninth and twelfth grades were asked to identify which words, in their judgment, were key words in written materials. Relationship of these choices to skilled readers, to words derived from passage analysis, and to random selections of hypothetical subjects…

  18. Hepatocyte Nuclear Factor 4 Alpha Is a Key Factor Related to Depression and Physiological Homeostasis in the Mouse Brain

    PubMed Central

    Yamanishi, Kyosuke; Doe, Nobutaka; Sumida, Miho; Watanabe, Yuko; Yoshida, Momoko; Yamamoto, Hideyuki; Xu, Yunfeng; Li, Wen; Yamanishi, Hiromichi; Okamura, Haruki; Matsunaga, Hisato

    2015-01-01

    Major depressive disorder (MDD) is a common psychiatric disorder that involves marked disabilities in global functioning, anorexia, and severe medical comorbidities. MDD is associated with not only psychological and sociocultural problems, but also pervasive physical dysfunctions such as metabolic, neurobiological and immunological abnormalities. Nevertheless, the mechanisms underlying the interactions between these factors have yet to be determined in detail. The aim of the present study was to identify the molecular mechanisms responsible for the interactions between MDD and dysregulation of physiological homeostasis, including immunological function as well as lipid metabolism, coagulation, and hormonal activity in the brain. We generated depression-like behavior in mice using chronic mild stress (CMS) as a model of depression. We compared the gene expression profiles in the prefrontal cortex (PFC) of CMS and control mice using microarrays. We subsequently categorized genes using two web-based bioinformatics applications: Ingenuity Pathway Analysis and The Database for Annotation, Visualization, and Integrated Discovery. We then confirmed significant group-differences by analyzing mRNA and protein expression levels not only in the PFC, but also in the thalamus and hippocampus. These web tools revealed that hepatocyte nuclear factor 4 alpha (Hnf4a) may exert direct effects on various genes specifically associated with amine synthesis, such as genes involved in serotonin metabolism and related immunological functions. Moreover, these genes may influence lipid metabolism, coagulation, and hormonal activity. We also confirmed the significant effects of Hnf4a on both mRNA and protein expression levels in the brain. These results suggest that Hnf4a may have a critical influence on physiological homeostasis under depressive states, and may be associated with the mechanisms responsible for the interactions between MDD and the dysregulation of physiological homeostasis

  19. Induction factor optimization through variable lift control

    NASA Astrophysics Data System (ADS)

    Cooney, John; Corke, Thomas; Nelson, Robert; Williams, Theodore

    2011-11-01

    Due to practical design limitations coupled with the detrimental effects posed by complex wind regimes, modern wind turbines struggle to maintain or even reach ideal operational states. With additional gains through traditional approaches becoming more difficult and costly, active lift control represents a more attractive option for future designs. Here, plasma actuators have been explored experimentally in trailing edge applications for use in attached flow regimes. This authority would be used to drive the axial induction factor toward the ideal given by the Betz limit through distributed lift control thereby enhancing energy capture. Predictions of power improvement achievable by this methodology are made with blade - element momentum theory but will eventually be demonstrated in the field at the Laboratory for Enhanced Wind Energy Design, currently under construction at the University of Notre Dame.

  20. Long-distance continuous-variable quantum key distribution by controlling excess noise

    PubMed Central

    Huang, Duan; Huang, Peng; Lin, Dakai; Zeng, Guihua

    2016-01-01

    Quantum cryptography founded on the laws of physics could revolutionize the way in which communication information is protected. Significant progresses in long-distance quantum key distribution based on discrete variables have led to the secure quantum communication in real-world conditions being available. However, the alternative approach implemented with continuous variables has not yet reached the secure distance beyond 100 km. Here, we overcome the previous range limitation by controlling system excess noise and report such a long distance continuous-variable quantum key distribution experiment. Our result paves the road to the large-scale secure quantum communication with continuous variables and serves as a stepping stone in the quest for quantum network. PMID:26758727

  1. Long-distance continuous-variable quantum key distribution by controlling excess noise

    NASA Astrophysics Data System (ADS)

    Huang, Duan; Huang, Peng; Lin, Dakai; Zeng, Guihua

    2016-01-01

    Quantum cryptography founded on the laws of physics could revolutionize the way in which communication information is protected. Significant progresses in long-distance quantum key distribution based on discrete variables have led to the secure quantum communication in real-world conditions being available. However, the alternative approach implemented with continuous variables has not yet reached the secure distance beyond 100 km. Here, we overcome the previous range limitation by controlling system excess noise and report such a long distance continuous-variable quantum key distribution experiment. Our result paves the road to the large-scale secure quantum communication with continuous variables and serves as a stepping stone in the quest for quantum network.

  2. Long-distance continuous-variable quantum key distribution by controlling excess noise.

    PubMed

    Huang, Duan; Huang, Peng; Lin, Dakai; Zeng, Guihua

    2016-01-01

    Quantum cryptography founded on the laws of physics could revolutionize the way in which communication information is protected. Significant progresses in long-distance quantum key distribution based on discrete variables have led to the secure quantum communication in real-world conditions being available. However, the alternative approach implemented with continuous variables has not yet reached the secure distance beyond 100 km. Here, we overcome the previous range limitation by controlling system excess noise and report such a long distance continuous-variable quantum key distribution experiment. Our result paves the road to the large-scale secure quantum communication with continuous variables and serves as a stepping stone in the quest for quantum network. PMID:26758727

  3. Evolving Systems: Adaptive Key Component Control and Inheritance of Passivity and Dissipativity

    NASA Technical Reports Server (NTRS)

    Frost, S. A.; Balas, M. J.

    2010-01-01

    We propose a new framework called Evolving Systems to describe the self-assembly, or autonomous assembly, of actively controlled dynamical subsystems into an Evolved System with a higher purpose. Autonomous assembly of large, complex flexible structures in space is a target application for Evolving Systems. A critical requirement for autonomous assembling structures is that they remain stable during and after assembly. The fundamental topic of inheritance of stability, dissipativity, and passivity in Evolving Systems is the primary focus of this research. In this paper, we develop an adaptive key component controller to restore stability in Nonlinear Evolving Systems that would otherwise fail to inherit the stability traits of their components. We provide sufficient conditions for the use of this novel control method and demonstrate its use on an illustrative example.

  4. Biological activity in Technosols as a key factor of their structure

    NASA Astrophysics Data System (ADS)

    Watteau, Françoise; Villemin, Geneviève; Bouchard, Adeline; Monserié, Marie-France; Séré, Geoffroy; Schwartz, Christophe; Morel, Jean-Louis

    2010-05-01

    )availability. HAP also contributed to the aggregation of technogenic constituents in Technosol 1. The biological activity generated by the presence of exogenous organic matter is thus in short (0-2 years) and mean (30 years) terms, a key factor of the structuration and by there of the pedogenesis of Technosols.

  5. On the Security of a Two-Factor Authentication and Key Agreement Scheme for Telecare Medicine Information Systems.

    PubMed

    Arshad, Hamed; Teymoori, Vahid; Nikooghadam, Morteza; Abbassi, Hassan

    2015-08-01

    Telecare medicine information systems (TMISs) aim to deliver appropriate healthcare services in an efficient and secure manner to patients. A secure mechanism for authentication and key agreement is required to provide proper security in these systems. Recently, Bin Muhaya demonstrated some security weaknesses of Zhu's authentication and key agreement scheme and proposed a security enhanced authentication and key agreement scheme for TMISs. However, we show that Bin Muhaya's scheme is vulnerable to off-line password guessing attacks and does not provide perfect forward secrecy. Furthermore, in order to overcome the mentioned weaknesses, we propose a new two-factor anonymous authentication and key agreement scheme using the elliptic curve cryptosystem. Security and performance analyses demonstrate that the proposed scheme not only overcomes the weaknesses of Bin Muhaya's scheme, but also is about 2.73 times faster than Bin Muhaya's scheme. PMID:26084586

  6. Air moisture control on ocean surface temperature, hidden key to the warm bias enigma

    NASA Astrophysics Data System (ADS)

    Hourdin, Frédéric; Gǎinusǎ-Bogdan, Alina; Braconnot, Pascale; Dufresne, Jean-Louis; Traore, Aboul-Khadre; Rio, Catherine

    2015-12-01

    The systematic overestimation by climate models of the surface temperature over the eastern tropical oceans is generally attributed to an insufficient oceanic cooling or to an underestimation of stratocumulus clouds. We show that surface evaporation contributes as much as clouds to the dispersion of the warm bias intensity in a multimodel simulations ensemble. The models with the largest warm biases are those with the highest surface heating by radiation and lowest evaporative cooling in atmospheric simulations with prescribed sea surface temperatures. Surface evaporation also controls the amplitude of the surface temperature response to this overestimated heating, when the atmosphere is coupled to an ocean. Evaporation increases with temperature both because of increasing saturation humidity and of an unexpected drying of the near-surface air. Both the origin of the bias and this temperature adjustment point to the key role of near-surface relative humidity and its control by the atmospheric model.

  7. A Genome-wide Regulatory Network Identifies Key Transcription Factors for Memory CD8+ T Cell Development

    PubMed Central

    Hu, Guangan; Chen, Jianzhu

    2014-01-01

    Memory CD8+ T cell development is defined by the expression of a specific set of memory signature genes (MSGs). Despite recent progress, many components of the transcriptional control of memory CD8+ T cell development are still unknown. To identify transcription factors (TFs) and their interactions in memory CD8+ T cell development, we construct a genome-wide regulatory network and apply it to identify key TFs that regulate MSGs. Most of the known TFs in memory CD8+ T cell development are rediscovered and about a dozen new TFs are also identified. Sox4, Bhlhe40, Bach2 and Runx2 are experimentally verified and Bach2 is further shown to promote both development and recall proliferation of memory CD8+ T cells through Prdm1 and Id3. Gene perturbation study identifies the mode of interactions among the TFs with Sox4 as a hub. The identified TFs and insights into their interactions should facilitate further dissection of molecular mechanisms underlying memory CD8+ T cell development. PMID:24335726

  8. Polyacrylamide grafted cellulose as an eco-friendly flocculant: Key factors optimization of flocculation to surfactant effluent.

    PubMed

    Zhu, Hangcheng; Zhang, Yong; Yang, Xiaogang; Shao, Lan; Zhang, Xiumei; Yao, Juming

    2016-01-01

    The discharge of effluents from surfactant manufacturers is giving rise to increasingly serious environmental problems. In order to develop the eco-friendly flocculation materials to achieve effective removal of pollutants from the surfactant effluents, the bamboo pulp cellulose from Phyllostachys heterocycla is employed as the skeleton material to synthesize an eco-friendly bamboo pulp cellulose-g-polyacrylamide (BPC-g-PAM) for flocculation. The BPC-g-PAM is used with the metal ions as the coagulant to treat the effluent from a surfactant manufacturer. The response surface methodology coupled with Box-behnken design is employed to optimize the key factors of coagulation-flocculation. The results show that the combination of Fe(3+) with BPC-g-PAM achieves the best coagulation-flocculation performance like, the fast treatment time, minimum coagulant and BPC-g-PAM dosages compared with the other two combinations of Al(3+) with BPC-g-PAM and Ca(2+) with BPC-g-PAM. Therefore, the combination of Fe(3+) with BPC-g-PAM is expected to promote its application for the pollution control in the surfactant manufacturers. PMID:26453862

  9. A Comprehensive Test of General Strain Theory: Key Strains, Situational- and Trait-Based Negative Emotions, Conditioning Factors, and Delinquency

    ERIC Educational Resources Information Center

    Moon, Byongook; Morash, Merry; McCluskey, Cynthia Perez; Hwang, Hye-Won

    2009-01-01

    Using longitudinal data on South Korean youth, the authors addressed limitations of previous tests of general strain theory (GST), focusing on the relationships among key strains, situational- and trait-based negative emotions, conditioning factors, and delinquency. Eight types of strain previously shown most likely to result in delinquency,…

  10. Problem-Based Learning Environment in Basic Computer Course: Pre-Service Teachers' Achievement and Key Factors for Learning

    ERIC Educational Resources Information Center

    Efendioglu, Akin

    2015-01-01

    This experimental study aims to determine pre-service teachers' achievements and key factors that affect the learning process with regard to problem-based learning (PBL) and lecture-based computer course (LBCC) conditions. The research results showed that the pre-service teachers in the PBL group had significantly higher achievement scores than…

  11. Factors influencing birth control habits in Victoria.

    PubMed

    Selwood, T; Leeton, J

    1981-02-01

    A survey was conducted in March 1978 for the purpose of comparing the contraceptive habits of Melbourne and ex-Melbourne populations in Victoria. Of the 1312 records of sexually active persons collected in 1978, 1254 of those persons were between the ages of 15 and 49. Recorded information included age, sex, marital status, and place of domicile (Melbourne or ex-Melbourne, Victoria). When the Melbourne population was compared with the rest of Victoria, the proportion using each method of contraception was much the same for each group. A marked difference was the proportion using withdrawal in Melbourne; this was over 3 times the proportion among the ex-Melbourne population. Over 35% of persons under age 30 used oral contraceptives (OCs), compared with 24.2 in the over 30 age range. Barrier methods and natural family planning methods and withdrawal were commonly used by the older age groups. A large proportion of the over age 30 group used sterilization and hysterectomy as forms of birth control. Individuals in "de facto" relationships showed a tendency towards more reliable forms of contraception than did other groups. Only 20.3% were not using some form of contraception. Single persons were frequent OC users and users of barrier methods. 28.1% used no form of contraception. The sex of the person interviewed in the survey revealed a bias. Males tended to report male birth control methods and female reported female methods rather than those used by partners of the opposite sex. Marital status influenced birth control choice. The choice of birth control for each marital status was influenced by the confounding factor of mean age of each group. PMID:7247847

  12. Genome-Wide Analysis of Wilms' Tumor 1-Controlled Gene Expression in Podocytes Reveals Key Regulatory Mechanisms.

    PubMed

    Kann, Martin; Ettou, Sandrine; Jung, Youngsook L; Lenz, Maximilian O; Taglienti, Mary E; Park, Peter J; Schermer, Bernhard; Benzing, Thomas; Kreidberg, Jordan A

    2015-09-01

    The transcription factor Wilms' tumor suppressor 1 (WT1) is key to podocyte development and viability; however, WT1 transcriptional networks in podocytes remain elusive. We provide a comprehensive analysis of the genome-wide WT1 transcriptional network in podocytes in vivo using chromatin immunoprecipitation followed by sequencing (ChIPseq) and RNA sequencing techniques. Our data show a specific role for WT1 in regulating the podocyte-specific transcriptome through binding to both promoters and enhancers of target genes. Furthermore, we inferred a podocyte transcription factor network consisting of WT1, LMX1B, TCF21, Fox-class and TEAD family transcription factors, and MAFB that uses tissue-specific enhancers to control podocyte gene expression. In addition to previously described WT1-dependent target genes, ChIPseq identified novel WT1-dependent signaling systems. These targets included components of the Hippo signaling system, underscoring the power of genome-wide transcriptional-network analyses. Together, our data elucidate a comprehensive gene regulatory network in podocytes suggesting that WT1 gene regulatory function and podocyte cell-type specification can best be understood in the context of transcription factor-regulatory element network interplay. PMID:25636411

  13. Dynamic Transcription Factor Activity Profiles Reveal Key Regulatory Interactions During Megakaryocytic and Erythroid Differentiation

    PubMed Central

    Duncan, Mark T.; Shin, Seungjin; Wu, Jia J.; Mays, Zachary; Weng, Stanley; Bagheri, Neda; Miller, William M.; Shea, Lonnie D.

    2014-01-01

    The directed differentiation toward erythroid (E) or megakaryocytic (MK) lineages by the MK-E progenitor (MEP) could enhance the ex vivo generation of red blood cells and platelets for therapeutic transfusions. The lineage choice at the MEP bifurcation is controlled in large part by activity within the intracellular signal transduction network, the output of which determines the activity of transcription factors (TFs) and ultimately gene expression. Although many TFs have been implicated, E or MK differentiation is a complex process requiring multiple days, and the dynamics of TF activities during commitment and terminal maturation are relatively unexplored. Herein, we applied a living cell array for the large-scale, dynamic quantification of TF activities during MEP bifurcation. A panel of hematopoietic TFs (GATA-1, GATA-2, SCL/TAL1, FLI-1, NF-E2, PU.1, c-Myb) was characterized during E and MK differentiation of bipotent K562 cells. Dynamic TF activity profiles associated with differentiation towards each lineage were identified, and validated with previous reports. From these activity profiles, we show that GATA-1 is an important hub during early hemin- and PMA-induced differentiation, and reveal several characteristic TF interactions for E and MK differentiation that confirm regulatory mechanisms documented in the literature. Additionally, we highlight several novel TF interactions at various stages of E and MK differentiation. Furthermore, we investigated the mechanism by which nicotinamide (NIC) promoted terminal MK maturation using an MK-committed cell line, CHRF-288-11 (CHRF). Concomitant with its enhancement of ploidy, NIC strongly enhanced the activity of three TFs with known involvement in terminal MK maturation: FLI-1, NF-E2, and p53. Dynamic profiling of TF activity represents a novel tool to complement traditional assays focused on mRNA and protein expression levels to understand progenitor cell differentiation. PMID:24853077

  14. Dynamic transcription factor activity profiles reveal key regulatory interactions during megakaryocytic and erythroid differentiation.

    PubMed

    Duncan, Mark T; Shin, Seungjin; Wu, Jia J; Mays, Zachary; Weng, Stanley; Bagheri, Neda; Miller, William M; Shea, Lonnie D

    2014-10-01

    The directed differentiation toward erythroid (E) or megakaryocytic (MK) lineages by the MK-E progenitor (MEP) could enhance the ex vivo generation of red blood cells and platelets for therapeutic transfusions. The lineage choice at the MEP bifurcation is controlled in large part by activity within the intracellular signal transduction network, the output of which determines the activity of transcription factors (TFs) and ultimately gene expression. Although many TFs have been implicated, E or MK differentiation is a complex process requiring multiple days, and the dynamics of TF activities during commitment and terminal maturation are relatively unexplored. Herein, we applied a living cell array for the large-scale, dynamic quantification of TF activities during MEP bifurcation. A panel of hematopoietic TFs (GATA-1, GATA-2, SCL/TAL1, FLI-1, NF-E2, PU.1, c-Myb) was characterized during E and MK differentiation of bipotent K562 cells. Dynamic TF activity profiles associated with differentiation towards each lineage were identified, and validated with previous reports. From these activity profiles, we show that GATA-1 is an important hub during early hemin- and PMA-induced differentiation, and reveal several characteristic TF interactions for E and MK differentiation that confirm regulatory mechanisms documented in the literature. Additionally, we highlight several novel TF interactions at various stages of E and MK differentiation. Furthermore, we investigated the mechanism by which nicotinamide (NIC) promoted terminal MK maturation using an MK-committed cell line, CHRF-288-11 (CHRF). Concomitant with its enhancement of ploidy, NIC strongly enhanced the activity of three TFs with known involvement in terminal MK maturation: FLI-1, NF-E2, and p53. Dynamic profiling of TF activity represents a novel tool to complement traditional assays focused on mRNA and protein expression levels to understand progenitor cell differentiation. PMID:24853077

  15. Factors controlling sulfur concentrations in volcanic apatite

    USGS Publications Warehouse

    Peng, G.; Luhr, J.F.; McGee, J.J.

    1997-01-01

    Apatite crystals from two types of samples were analyzed by electron microprobe for 15 major and trace elements: (1) apatite in H2O- and S-saturated experimental charges of the 1982 El Chicho??n trachyandesite and (2) apatite in volcanic rocks erupted from 20 volcanoes. The SO3 contents of the experimental apatite increase with increasing oxygen fugacity (fo2), from ???0.04 wt% in reduced charges buffered by fayalite-magnetite-quartz (FMQ), to 1.0-2.6 wt% in oxidized charges buffered by manganosite-hausmanite (MNH) or magnetite-hematite (MTH). The SO3 contents of MNH- and MTH-buffered apatite also generally increase with increasing pressure from 2 to 4 kbar and decreasing temperature from 950 to 800??C. The partition coefficient for SO3 between apatite and oxidized melt increases with decreasing temperature but appears to be independent of pressure. Apatites in volcanic rocks show a wide range of SO3 contents (<0.04 to 0.63 wt%). Our sample set includes one group known to contain primary anhydrite and a second group inferred to have been free of primary anhydrite. No systematic differences in apatite S contents are observed between these two groups. Our study was initiated to define the factors controlling S contents in apatite and to evaluate the hypothesis that high S contents in apatite could be characteristic of S-rich anhydrite-bearing magmas such as those erupted from El Chicho??n in 1982 and Pinatubo in 1991. This hypothesis is shown to be invalid, probably chiefly a consequence of the slow intra-crystaline diffusion that limits re-equilibration between early formed apatite and the evolving silicate melt. Contributing factors include early crystallization of most apatite over a relatively small temperature interval, common late-stage magmatic enrichment of S, progressive oxidation during magmatic evolution, and strong controls on S contents in apatite exerted fo2, temperature, and pressure.

  16. Local Text Cohesion, Reading Ability and Individual Science Aspirations: Key Factors Influencing Comprehension in Science Classes

    ERIC Educational Resources Information Center

    Hall, Sophie S.; Kowalski, Rebecca; Paterson, Kevin B.; Basran, Jaskaran; Filik, Ruth; Maltby, John

    2015-01-01

    In response to the concern of the need to improve the scientific skills of school children, this study investigated the influence of text design (in terms of text cohesion) and individual differences, with the aim of identifying pathways to improving science education in early secondary school (Key Stage 3). One hundred and four secondary school…

  17. Key Factors to Instructors' Satisfaction of Learning Management Systems in Blended Learning

    ERIC Educational Resources Information Center

    Al-Busaidi, Kamla Ali; Al-Shihi, Hafedh

    2012-01-01

    Learning Management System (LMS) enables institutions to administer their educational resources, and support their traditional classroom education and distance education. LMS survives through instructors' continuous use, which may be to a great extent associated with their satisfaction of the LMS. Consequently, this study examined the key factors…

  18. Factors Controlling Liquid Particulate Matter in Amazonia

    NASA Astrophysics Data System (ADS)

    Bateman, A. P.; Gong, Z.; de Sá, S. S.; Wernis, R. A.; Yee, L.; Isaacman-VanWertz, G. A.; Goldstein, A. H.; Castillo, P.; Sedlacek, A. J., III; Palm, B. B.; Campuzano-Jost, P.; Day, D. A.; Hu, W.; Jimenez, J. L.; Alexander, L.; Manzi, A. O.; Souza, R. A. F. D.; Artaxo, P.; Martin, S. T.

    2015-12-01

    The hygroscopic response of particulate matter (PM) during GoAmazon 2014/5 was investigated through the use of particle rebound (or lack thereof) during impaction. The hygroscopic response was measured online and in real-time using a custom designed impaction apparatus. The impaction apparatus was calibrated with respect to particle viscosity indicating a liquid state (viscosity <102 Pa s) for complete adherence (no particle rebound). By varying the PM water content and observing particle rebound as a function of RH (up to 98%), the hygroscopic response and phase state of the PM under investigation was determined. The hygroscopic response curves were categorized according to the rebound fraction at high RH (80 - 98%) bounded by two extremes. 1) Time periods that resemble pure SOM generated under controlled chamber conditions, where no particle rebound is observed above 80% RH. 2) Time periods that a large fraction (10 - 40%) of particles rebound at RH values >95%, an indication of hydrophobic particles. The role of anthropogenic and biogenic factors in controlling the hygroscopic response of PM in Amazonia is investigated through meteorological conditions and particle chemical composition.

  19. Key factors influencing ADME properties of therapeutic proteins: A need for ADME characterization in drug discovery and development

    PubMed Central

    Tibbitts, Jay; Canter, David; Graff, Ryan; Smith, Alison; Khawli, Leslie A.

    2016-01-01

    abstract Protein therapeutics represent a diverse array of biologics including antibodies, fusion proteins, and therapeutic replacement enzymes. Since their inception, they have revolutionized the treatment of a wide range of diseases including respiratory, vascular, autoimmune, inflammatory, infectious, and neurodegenerative diseases, as well as cancer. While in vivo pharmacokinetic, pharmacodynamic, and efficacy studies are routinely carried out for protein therapeutics, studies that identify key factors governing their absorption, distribution, metabolism, and excretion (ADME) properties have not been fully investigated. Thorough characterization and in-depth study of their ADME properties are critical in order to support drug discovery and development processes for the production of safer and more effective biotherapeutics. In this review, we discuss the main factors affecting the ADME characteristics of these large macromolecular therapies. We also give an overview of the current tools, technologies, and approaches available to investigate key factors that influence the ADME of recombinant biotherapeutic drugs, and demonstrate how ADME studies will facilitate their future development. PMID:26636901

  20. Somatostatin Interneurons Control a Key Component of Mismatch Negativity in Mouse Visual Cortex.

    PubMed

    Hamm, Jordan P; Yuste, Rafael

    2016-07-19

    Patients with schizophrenia have deficient sensory processing, undermining how they perceive and relate to a changing environment. This impairment can be captured by the reduced mismatch negativity (MMN) index, an electroencephalographic biomarker of psychosis. The biological factors contributing to MMN are unclear, though mouse research, in which genetic and optical methods could be applied, has given some insight. Using fast two-photon calcium imaging and multielectrode recordings in awake mice, we find that visual cortical circuits display adapted (decreased) responses to repeated stimuli and amplified responses to a deviant stimulus, the key component of human MMN. Moreover, pharmacogenetic silencing of somatostatin-containing interneurons specifically eliminated this amplification, along with its associated theta/alpha-band response, leaving stimulus-specific adaption and related gamma-band modulations intact. Our results validate a mouse model of MMN and suggest that abnormalities in somatostatin-containing interneurons cause sensory deficits underlying MMN and schizophrenia. PMID:27396334

  1. The Promise of Virtual Teams: Identifying Key Factors in Effectiveness and Failure

    ERIC Educational Resources Information Center

    Horwitz, Frank M.; Bravington, Desmond; Silvis, Ulrik

    2006-01-01

    Purpose: The aim of the investigation is to identify enabling and disenabling factors in the development and operation of virtual teams; to evaluate the importance of factors such as team development, cross-cultural variables, leadership, communication and social cohesion as contributors to virtual team effectiveness. Design/methodology/approach:…

  2. From Loose Groups to Effective Teams: The Nine Key Factors of the Team Landscape.

    ERIC Educational Resources Information Center

    Sheard, A. G.; Kakabadse, A. P.

    2002-01-01

    A loose group of individuals working on a task differs from an effective team on nine factors: clearly defined goals, priorities, roles and responsibilities, self-awareness, leadership, group dynamics, communications, content, and infrastructure. Ways to eliminate barriers and speed formation of effective teams could be based on those factors.…

  3. Exercise-induced neuroprotective effects on neurodegenerative diseases: the key role of trophic factors.

    PubMed

    Campos, Carlos; Rocha, Nuno Barbosa F; Lattari, Eduardo; Paes, Flávia; Nardi, António E; Machado, Sérgio

    2016-06-01

    Age-related neurodegenerative disorders, like Alzheimer's or Parkinson's disease, are becoming a major issue to public health care. Currently, there is no effective pharmacological treatment to address cognitive impairment in these patients. Here, we aim to explore the role of exercise-induced trophic factor enhancement in the prevention or delay of cognitive decline in patients with neurodegenerative diseases. There is a significant amount of evidence from animal and human studies that links neurodegenerative related cognitive deficits with changes on brain and peripheral trophic factor levels. Several trials with elderly individuals and patients with neurodegenerative diseases report exercise induced cognitive improvements and changes on trophic factor levels including BDNF, IGF-I, among others. Further studies with healthy aging and clinical populations are needed to understand how diverse exercise interventions produce different variations in trophic factor signaling. Genetic profiles and potential confounders regarding trophic factors should also be addressed in future trials. PMID:27086703

  4. Transition of basaltic lava from pahoehoe to aa, Kilauea Volcano, Hawaii: Field observations and key factors

    USGS Publications Warehouse

    Peterson, D.W.; Tilling, R.I.

    1980-01-01

    Nearly all Hawaiian basaltic lava erupts as pahoehoe, and some changes to aa during flowage and cooling; factors governing the transition involve certain critical relations between viscosity and rate of shear strain. If the lava slows, cools, and stops in direct response to concomitant increase in viscosity before these critical relations are reached, it remains pahoehoe. But, if flow mechanics (flow rate, flow dimensions, slope, momentum, etc.) impel the lava to continue to move and deform even after it has become highly viscous, the critical relations may be reached and the lava changes to aa. Typical modes of transition from pahoehoe to aa include: (1) spontaneous formation of relatively stiff clots in parts of the flowing lava where shear rate is highest; these clots grow into discrete, rough, sticky masses to which the remaining fluid lava incrementally adheres; (2) fragmentation and immersion of solid or semi-solid surface crusts of pahoehoe by roiling movements of the flow, forming cores of discrete, tacky masses; (3) sudden renewed movement of lava stored and cooled within surface reservoirs to form clots. The masses, fragments, and clots in these transition modes are characterized by spinose, granulated surfaces; as flow movement continues, the masses and fragments aggregate, fracture, and grind together, completing the transition to aa. Observations show that the critical relation between viscosity and rate of shear strain is inverse: if viscosity is low, a high rate of shear is required to begin the transition to aa; conversely, if viscosity is high, a much lower rate of shear will induce the transition. These relations can be demonstrated qualitatively with simple graphs, which can be used to examine the flow history of any selected finite lava element by tracing the path represented by its changing viscosity and shear rate. A broad, diffuse "transition threshold zone" in these graphs portrays the inverse critical relation between viscosity and shear

  5. Aerial and tidal transport of mosquito control pesticides into the Florida Keys National Marine Sanctuary.

    PubMed

    Pierce, R H; Henry, M S; Blum, T C; Mueller, E M

    2005-05-01

    This project was undertaken as the initial monitoring program to determine if mosquito adulticides applied along the Florida Keys cause adverse ecological effects in the Florida Keys National Marine Sanctuary (FKNMS). The study monitored the distribution and persistence of two mosquito adulticides, permethrin and dibrom (naled), during three separate routine applications by the Florida Keys Mosquito Control District. The approach was to determine if toxic concentrations of the pesticides entered the FKNMS by aerial drift or tidal transport. The amount of pesticide entering the FKNMS by way of aerial drift was monitored by collection on glass fiber filter pads, set on floats in a grid pattern on either side of the FKNMS. Permethrin was recovered from filter pads on the leeward side for each of the three applications, ranging from 0.5 to 50.1 microg/m(2) throughout the study. Tidal current transport was monitored by collection of surface and subsurface water samples at each grid site. Tidal transport of naled and dichlorvos (naled degradation product) was apparent in the adjacent waters of the FKNMS. These compounds were detected in subsurface, offshore water at 0.1 to 0.6 microg/1, 14 hr after application. Permethrin was not detected in offshore water samples; however, concentrations ranging from 5.1 to 9.4 microg/l were found in surface water from the canal system adjacent to the application route. Comparison of the observed environmental concentrations with toxicity data (permethrin LC-50, 96 hr for Mysidopsis bahia = 0.02 microg/l) indicated a potential hazard to marine invertebrates in the canals with possible tidal transport to other areas. PMID:17465151

  6. URI in athletes: are mucosal immunity and cytokine responses key risk factors?

    PubMed

    Gleeson, Michael; Bishop, Nicolette C

    2013-07-01

    Infection incidence among athletes is highest during periods of intensified training and competition and after strenuous long-distance events. Which aspects of depressed immune function are responsible for this increased infection risk are not known, but our hypothesis is that lower salivary immunoglobulin A (IgA) secretion and a higher antiinflammatory cytokine response to antigen exposure are key determinants of infection risk. PMID:23792489

  7. A consideration of select pre-trauma factors as key vulnerabilities in PTSD

    PubMed Central

    Bomyea, Jessica; Risbrough, Victoria; Lang, Ariel J.

    2012-01-01

    Posttraumatic stress disorder (PTSD) is a pathological response to a traumatic event. A number of risk and vulnerability factors predicting PTSD development have been identified in the literature. Many of these variables are specific factors occurring during and after exposure to a traumatic event or are not measured prospectively to assess temporal sequence. Recent research, however, has begun to focus on pre-trauma individual differences that could contribute to risk for developing PTSD. The present review proposes that a number of biological and cognitive vulnerability factors place individuals at risk for PTSD development prior to the actual experience of trauma. Accordingly, this review provides a summary of evidence for a select number of these factors as pre-trauma vulnerabilities to PTSD. Included is a discussion of biological factors, including molecular genetic studies of systems regulating serotonin, catecholamines, and glucocorticoids as well as aspects of the neuroendocrine system. Specific cognitive factors are also considered, including intelligence, neuropsychological functioning and cognitive biases such as negative attributional style and appraisals. For each factor, the present review summarizes evidence to date regarding PTSD vulnerability and highlights directions for future research in this area. PMID:22917742

  8. A large-scale, in vivo transcription factor screen defines bivalent chromatin as a key property of regulatory factors mediating Drosophila wing development

    PubMed Central

    Schertel, Claus; Albarca, Monica; Rockel-Bauer, Claudia; Kelley, Nicholas W.; Bischof, Johannes; Hens, Korneel

    2015-01-01

    Transcription factors (TFs) are key regulators of cell fate. The estimated 755 genes that encode DNA binding domain-containing proteins comprise ∼5% of all Drosophila genes. However, the majority has remained uncharacterized so far due to the lack of proper genetic tools. We generated 594 site-directed transgenic Drosophila lines that contain integrations of individual UAS-TF constructs to facilitate spatiotemporally controlled misexpression in vivo. All transgenes were expressed in the developing wing, and two-thirds induced specific phenotypic defects. In vivo knockdown of the same genes yielded a phenotype for 50%, with both methods indicating a great potential for misexpression to characterize novel functions in wing growth, patterning, and development. Thus, our UAS-TF library provides an important addition to the genetic toolbox of Drosophila research, enabling the identification of several novel wing development-related TFs. In parallel, we established the chromatin landscape of wing imaginal discs by ChIP-seq analyses of five chromatin marks and RNA Pol II. Subsequent clustering revealed six distinct chromatin states, with two clusters showing enrichment for both active and repressive marks. TFs that carry such “bivalent” chromatin are highly enriched for causing misexpression phenotypes in the wing, and analysis of existing expression data shows that these TFs tend to be differentially expressed across the wing disc. Thus, bivalently marked chromatin can be used as a marker for spatially regulated TFs that are functionally relevant in a developing tissue. PMID:25568052

  9. The physical size of transcription factors is key to transcriptional regulation in chromatin domains

    NASA Astrophysics Data System (ADS)

    Maeshima, Kazuhiro; Kaizu, Kazunari; Tamura, Sachiko; Nozaki, Tadasu; Kokubo, Tetsuro; Takahashi, Koichi

    2015-02-01

    Genetic information, which is stored in the long strand of genomic DNA as chromatin, must be scanned and read out by various transcription factors. First, gene-specific transcription factors, which are relatively small (˜50 kDa), scan the genome and bind regulatory elements. Such factors then recruit general transcription factors, Mediators, RNA polymerases, nucleosome remodellers, and histone modifiers, most of which are large protein complexes of 1-3 MDa in size. Here, we propose a new model for the functional significance of the size of transcription factors (or complexes) for gene regulation of chromatin domains. Recent findings suggest that chromatin consists of irregularly folded nucleosome fibres (10 nm fibres) and forms numerous condensed domains (e.g., topologically associating domains). Although the flexibility and dynamics of chromatin allow repositioning of genes within the condensed domains, the size exclusion effect of the domain may limit accessibility of DNA sequences by transcription factors. We used Monte Carlo computer simulations to determine the physical size limit of transcription factors that can enter condensed chromatin domains. Small gene-specific transcription factors can penetrate into the chromatin domains and search their target sequences, whereas large transcription complexes cannot enter the domain. Due to this property, once a large complex binds its target site via gene-specific factors it can act as a ‘buoy’ to keep the target region on the surface of the condensed domain and maintain transcriptional competency. This size-dependent specialization of target-scanning and surface-tethering functions could provide novel insight into the mechanisms of various DNA transactions, such as DNA replication and repair/recombination.

  10. The physical size of transcription factors is key to transcriptional regulation in chromatin domains.

    PubMed

    Maeshima, Kazuhiro; Kaizu, Kazunari; Tamura, Sachiko; Nozaki, Tadasu; Kokubo, Tetsuro; Takahashi, Koichi

    2015-02-18

    Genetic information, which is stored in the long strand of genomic DNA as chromatin, must be scanned and read out by various transcription factors. First, gene-specific transcription factors, which are relatively small (∼50 kDa), scan the genome and bind regulatory elements. Such factors then recruit general transcription factors, Mediators, RNA polymerases, nucleosome remodellers, and histone modifiers, most of which are large protein complexes of 1-3 MDa in size. Here, we propose a new model for the functional significance of the size of transcription factors (or complexes) for gene regulation of chromatin domains. Recent findings suggest that chromatin consists of irregularly folded nucleosome fibres (10 nm fibres) and forms numerous condensed domains (e.g., topologically associating domains). Although the flexibility and dynamics of chromatin allow repositioning of genes within the condensed domains, the size exclusion effect of the domain may limit accessibility of DNA sequences by transcription factors. We used Monte Carlo computer simulations to determine the physical size limit of transcription factors that can enter condensed chromatin domains. Small gene-specific transcription factors can penetrate into the chromatin domains and search their target sequences, whereas large transcription complexes cannot enter the domain. Due to this property, once a large complex binds its target site via gene-specific factors it can act as a 'buoy' to keep the target region on the surface of the condensed domain and maintain transcriptional competency. This size-dependent specialization of target-scanning and surface-tethering functions could provide novel insight into the mechanisms of various DNA transactions, such as DNA replication and repair/recombination. PMID:25563431

  11. Factors Controlling the Fragmentation Behavior of Magma

    NASA Astrophysics Data System (ADS)

    Richard, D.; Scheu, B.; Mueller, S.; Spieler, O.; Dingwell, D. B.

    2006-12-01

    Five volcanoes of explosive eruptive behavior from the Ring of Fire were selected to investigate the processes responsible for their degree of explosivity and eruptive style. These volcanoes are Colima, (Mexico), St. Augustine (USA), Bezymianny (Russia), Krakatau and Kelut (Indonesia). In an attempt to better understand the processes controlling fragmentation at these volcanoes, we performed shock-tube experiments with natural samples from these volcanoes at overpressures between 4 and 35 MPa at room temperature. Both fragmentation threshold and speed of fragmentation were determined. Previous studies have already shown that porosity is a first order parameter in eruption models and our recent results support this statement. However, it is clear that other factors such as permeability need to be considered to explain variations observed in fragmentation behavior. Colima sample series of 24 % porosity require overpressures of over 11 MPa to fragment, whereas other Colima sample series of 15 % porosity require overpressures of only 8 MPa to fragment. Permeability measurements confirmed a permeability of about one order of magnitude higher for the samples of 24 % porosity. However, this information alone does not necessarily provide an explanation for the large scatter seen in the fragmentation speed data within one sample series. Experimental data will be supported by textural microscopic analyses in order to provide more constraints on the dominant factors responsible for the scatter in fragmentation behavior. Explaining this scatter will help to shed light on the respective eruptive behavior of the investigated volcanoes and thus help to understand why, at the first glance, very "similar" volcanic systems may react in very different ways. This work is part of the BMBF project SUNDAARC, which aims to quantify the potential risk of selected highly-explosive volcanoes by combining field and laboratory investigations.

  12. Key analytic considerations in design and analysis of randomized controlled trials in osteoarthritis

    PubMed Central

    Losina, Elena; Ranstam, Jonas; Collins, Jamie; Schnitzer, Thomas J; Katz, Jeffrey N.

    2016-01-01

    Objective To highlight methodologic challenges pertinent to design, analysis, and reporting of results of randomized clinical trials in OA and offer practical suggestions to overcome these challenges. Design The topics covered in this paper include subject selection, randomization, approaches to handling missing data, subgroup analysis, sample size, and issues related to changing design mid-way through the study. Special attention is given to standardizing the reporting of results and economic analyses. Results Key findings include the importance of blinding and concealment, the distinction between superiority and non-inferiority trials, the need to minimize missing data, and appropriate analysis and interpretation of subgroup effects. Conclusion Investigators may use the findings and recommendations advanced in this paper to guide design and conduct of randomized controlled trials of interventions for osteoarthritis. PMID:25952341

  13. Enhanced Production of Insulin-like Growth Factor I Protein in Escherichia coli by Optimization of Five Key Factors

    PubMed Central

    Ranjbari, Javad; Babaeipour, Valiollah; Vahidi, Hossein; Moghimi, Hamidreza; Mofid, Mohammad Reza; Namvaran, Mohammad Mehdi; Jafari, Sevda

    2015-01-01

    Human insulin-like growth factor I (hIGF-I) is a kind of growth factor with clinical significance in medicine. Up to now, E. coli expression system has been widely used as a host to produce rhIGF-1 with high yields. Batch cultures as non-continuous fermentations were carried out to overproduce rhIGF-I in E. coli. The major objective of this study is over- production of recombinant human insulin-like growth factor I (rhIGF-I) through a developed process by recruiting effective factors in order to achieve the most recombinant protein. In this study we investigated the effect of culture medium, induction temperature and amount of inducer on cell growth and IGF-1 production. Taguchi design of experiments (DOE) method was used as the statistical method. Analysis of experimental data showed that maximum production of rhIGF-I was occurred in 32y culture medium at 32 °C and 0.05 Mm IPTG. Under this condition, 0.694 g/L of rhIGF-I was produced as the inclusion bodies. Following optimization of these three factors, we have also optimized the amount of glucose and induction time in 5 liter top bench bioreactor. Full factorial design of experiment method was used for these two factors as the statistical method. 10 g/L and OD600=5 were selected as the optimum point of Glucose amount and induction time, respectively. Finally, we reached to a concentration of 1.26 g/L rhIGF-1 at optimum condition. PMID:26330880

  14. Enhanced Production of Insulin-like Growth Factor I Protein in Escherichia coli by Optimization of Five Key Factors.

    PubMed

    Ranjbari, Javad; Babaeipour, Valiollah; Vahidi, Hossein; Moghimi, Hamidreza; Mofid, Mohammad Reza; Namvaran, Mohammad Mehdi; Jafari, Sevda

    2015-01-01

    Human insulin-like growth factor I (hIGF-I) is a kind of growth factor with clinical significance in medicine. Up to now, E. coli expression system has been widely used as a host to produce rhIGF-1 with high yields. Batch cultures as non-continuous fermentations were carried out to overproduce rhIGF-I in E. coli. The major objective of this study is over- production of recombinant human insulin-like growth factor I (rhIGF-I) through a developed process by recruiting effective factors in order to achieve the most recombinant protein. In this study we investigated the effect of culture medium, induction temperature and amount of inducer on cell growth and IGF-1 production. Taguchi design of experiments (DOE) method was used as the statistical method. Analysis of experimental data showed that maximum production of rhIGF-I was occurred in 32y culture medium at 32 °C and 0.05 Mm IPTG. Under this condition, 0.694 g/L of rhIGF-I was produced as the inclusion bodies. Following optimization of these three factors, we have also optimized the amount of glucose and induction time in 5 liter top bench bioreactor. Full factorial design of experiment method was used for these two factors as the statistical method. 10 g/L and OD600=5 were selected as the optimum point of Glucose amount and induction time, respectively. Finally, we reached to a concentration of 1.26 g/L rhIGF-1 at optimum condition. PMID:26330880

  15. Factors controlling water movement in acid spoils

    SciTech Connect

    Evangelou, V.P.; Grove, J.H.; Phillips, R.E.

    1982-12-01

    The rate of water movement through toxic spoils plays a major role in reclamation. The toxic chemical constituents found in spoils need to be leached beyond the six inch depth (the usual depth of lime incorporation) since they can easily move upward during periods of high evapotranspiration. The rate of water infiltration plays a role in effective utilization of rain water, and conversely, the amount of surface runoff dictates the degree of surface erosion. Underground water quality may be affected by rates of water movement through a toxic spoil zone. Factors that control water movement through acid spoils were investigated through the use of a column one meter long and 8.0 cm in internal diameter. The maximum hydraulic conductivity was observed in the upper portion of the column where minimum salt buildup occurred. The hydraulic conductivity in this region was 0.5 cm/hr. In the middle portion of the column where a salty (14.0 mmhos/cm) solution was encountered, the hydraulic conductivity was 0.08 cm/hr. In the lower portion of the column where the maximum salt buildup took place (16.8 mmhos/cm), the hydraulic conductivity was found to be 0.03 cm/hr. Similar results were obtained with a small column experiment using calcite and dolomite as different lime sources. The hydraulic conductivity in the dolomitic small column remained relatively unchanged with time and salt depletion.

  16. Factors controlling dimethylsulfide emission from salt marshes

    NASA Technical Reports Server (NTRS)

    Dacey, John W. H.; Wakeham, S. G.; Howes, B. L.

    1985-01-01

    The factors that control the emission of methylated gases from salt marshes are being studied. Research focusses on dimethylsulfide (DMS) formation and the mechanism of DMS and CH4 emission to the atmosphere. The approach is to consider the plants as valves regulating the emission of methylated gases to the atmosphere with the goal of developing appropriate methods for emission measurement. In the case of CH4, the sediment is the source and transport to the atmosphere occurs primarily through the internal gas spaces in the plants. The source of DMS appears to be dimethyl sulfoniopropionate (DMSP) which may play a role in osmoregulation in plant tissues. Concentrations of DMSP in leaves are typically several-fold higher than in roots and rhizomes. Even so, the large below ground biomass of this plant means that 2/3 of the DMSP in the ecosystem is below ground on the aerial basis. Upon introduction to sediment water, DMSP rapidly decomposes to DMS and acrylic acid. The solubility of a gas (its equilibrium vapor pressure) is a fundamental aspect of gas exchange kinetics. The first comprehensive study was conducted of DMS solubility in freshwater and seawater. Data suggest that the Setchenow relation holds for H at intermediate salinities collected. These data support the concept that the concentration of DMS in the atmosphere is far from equilibrium with seawater.

  17. Understanding key factors of users' intentions to repurchase and recommend digital items in social virtual worlds.

    PubMed

    Kim, Byoungsoo

    2012-10-01

    Given to the remarkable profitability of digital items in social virtual worlds (SVWs), such as SecondLife, Cyworld, and Habbo Hotel, it has become crucial to understand SVW users' postadoption behaviors toward digital items. This study develops a theoretical framework to examine key antecedents of users' intentions to repurchase and recommend digital items. Data collected from 256 users of digital items were empirically tested against the research model. The analysis results indicate that both user satisfaction and a perceived value play an important role in establishing users' postadoption intentions about digital items. Moreover, the results clearly show what roles perceived usefulness, perceived enjoyment, and perceived fee play in SVW environments. PMID:22924676

  18. Risk factors for conduct disorder and delinquency: key findings from longitudinal studies.

    PubMed

    Murray, Joseph; Farrington, David P

    2010-10-01

    Conduct disorder (CD) and delinquency are behavioural problems involving violation of major rules, societal norms, and laws. The prevalence of CD and delinquency peaks in mid-to-late adolescence. Both show considerable continuity over time. The most important studies of CD and delinquency have prospective longitudinal designs, large community samples, repeated personal interviews, measures of many possible risk factors, and both self-reports and official measures of antisocial behaviour. The most important risk factors that predict CD and delinquency include impulsiveness, low IQ and low school achievement, poor parental supervision, punitive or erratic parental discipline, cold parental attitude, child physical abuse, parental conflict, disrupted families, antisocial parents, large family size, low family income, antisocial peers, high delinquency rate schools, and high crime neighbourhoods. However, for many risk factors, it is not known whether they have causal effects. Future research should examine changes in risk factors and changes in CD and delinquency to identify the risk factors that are causes and those that are merely markers of other risk mechanisms. PMID:20964942

  19. Belongingness in Early Secondary School: Key Factors that Primary and Secondary Schools Need to Consider.

    PubMed

    Vaz, Sharmila; Falkmer, Marita; Ciccarelli, Marina; Passmore, Anne; Parsons, Richard; Black, Melissa; Cuomo, Belinda; Tan, Tele; Falkmer, Torbjörn

    2015-01-01

    It is unknown if, and how, students redefine their sense of school belongingness after negotiating the transition to secondary school. The current study used longitudinal data from 266 students with, and without, disabilities who negotiated the transition from 52 primary schools to 152 secondary schools. The study presents the 13 most significant personal student and contextual factors associated with belongingness in the first year of secondary school. Student perception of school belongingness was found to be stable across the transition. No variability in school belongingness due to gender, disability or household-socio-economic status (SES) was noted. Primary school belongingness accounted for 22% of the variability in secondary school belongingness. Several personal student factors (competence, coping skills) and school factors (low-level classroom task-goal orientation), which influenced belongingness in primary school, continued to influence belongingness in secondary school. In secondary school, effort-goal orientation of the student and perception of their school's tolerance to disability were each associated with perception of school belongingness. Family factors did not influence belongingness in secondary school. Findings of the current study highlight the need for primary schools to foster belongingness among their students at an early age, and transfer students' belongingness profiles as part of the hand-over documentation. Most of the factors that influenced school belongingness before and after the transition to secondary are amenable to change. PMID:26372554

  20. Belongingness in Early Secondary School: Key Factors that Primary and Secondary Schools Need to Consider

    PubMed Central

    Vaz, Sharmila; Falkmer, Marita; Ciccarelli, Marina; Passmore, Anne; Parsons, Richard; Black, Melissa; Cuomo, Belinda; Tan, Tele; Falkmer, Torbjörn

    2015-01-01

    It is unknown if, and how, students redefine their sense of school belongingness after negotiating the transition to secondary school. The current study used longitudinal data from 266 students with, and without, disabilities who negotiated the transition from 52 primary schools to 152 secondary schools. The study presents the 13 most significant personal student and contextual factors associated with belongingness in the first year of secondary school. Student perception of school belongingness was found to be stable across the transition. No variability in school belongingness due to gender, disability or household-socio-economic status (SES) was noted. Primary school belongingness accounted for 22% of the variability in secondary school belongingness. Several personal student factors (competence, coping skills) and school factors (low-level classroom task-goal orientation), which influenced belongingness in primary school, continued to influence belongingness in secondary school. In secondary school, effort-goal orientation of the student and perception of their school’s tolerance to disability were each associated with perception of school belongingness. Family factors did not influence belongingness in secondary school. Findings of the current study highlight the need for primary schools to foster belongingness among their students at an early age, and transfer students’ belongingness profiles as part of the hand-over documentation. Most of the factors that influenced school belongingness before and after the transition to secondary are amenable to change. PMID:26372554

  1. Key contribution of eIF4H-mediated translational control in tumor promotion

    PubMed Central

    Vaysse, Charlotte; Philippe, Céline; Martineau, Yvan; Quelen, Cathy; Hieblot, Corinne; Renaud, Claire; Nicaise, Yvan; Desquesnes, Aurore; Pannese, Maria; Filleron, Thomas; Escourrou, Ghislaine; Lawson, Malcolm; Rintoul, Robert C.; Delisle, Marie Bernadette; Pyronnet, Stéphane; Brousset, Pierre; Prats, Hervé; Touriol, Christian

    2015-01-01

    Dysregulated expression of translation initiation factors has been associated with carcinogenesis, but underlying mechanisms remains to be fully understood. Here we show that eIF4H (eukaryotic translation initiation factor 4H), an activator of the RNA helicase eIF4A, is overexpressed in lung carcinomas and predictive of response to chemotherapy. In lung cancer cells, depletion of eIF4H enhances sensitization to chemotherapy, decreases cell migration and inhibits tumor growth in vivo, in association with reduced translation of mRNA encoding cell-proliferation (c-Myc, cyclin D1) angiogenic (FGF-2) and anti-apoptotic factors (CIAP-1, BCL-xL). Conversely, each isoform of eIF4H acts as an oncogene in NIH3T3 cells by stimulating transformation, invasion, tumor growth and resistance to drug-induced apoptosis together with increased translation of IRES-containing or structured 5′UTR mRNAs. These results demonstrate that eIF4H plays a crucial role in translational control and can promote cellular transformation by preferentially regulating the translation of potent growth and survival factor mRNAs, indicating that eIF4H is a promising new molecular target for cancer therapy. PMID:26498689

  2. Adaptive Control Model Reveals Systematic Feedback and Key Molecules in Metabolic Pathway Regulation

    PubMed Central

    Moffitt, Richard A.; Merrill, Alfred H.; Wang, May D.

    2011-01-01

    Abstract Robust behavior in metabolic pathways resembles stabilized performance in systems under autonomous control. This suggests we can apply control theory to study existing regulation in these cellular networks. Here, we use model-reference adaptive control (MRAC) to investigate the dynamics of de novo sphingolipid synthesis regulation in a combined theoretical and experimental case study. The effects of serine palmitoyltransferase over-expression on this pathway are studied in vitro using human embryonic kidney cells. We report two key results from comparing numerical simulations with observed data. First, MRAC simulations of pathway dynamics are comparable to simulations from a standard model using mass action kinetics. The root-sum-square (RSS) between data and simulations in both cases differ by less than 5%. Second, MRAC simulations suggest systematic pathway regulation in terms of adaptive feedback from individual molecules. In response to increased metabolite levels available for de novo sphingolipid synthesis, feedback from molecules along the main artery of the pathway is regulated more frequently and with greater amplitude than from other molecules along the branches. These biological insights are consistent with current knowledge while being new that they may guide future research in sphingolipid biology. In summary, we report a novel approach to study regulation in cellular networks by applying control theory in the context of robust metabolic pathways. We do this to uncover potential insight into the dynamics of regulation and the reverse engineering of cellular networks for systems biology. This new modeling approach and the implementation routines designed for this case study may be extended to other systems. Supplementary Material is available at www.liebertonline.com/cmb. PMID:21314456

  3. Museum specimens reveal loss of pollen host plants as key factor driving wild bee decline in The Netherlands.

    PubMed

    Scheper, Jeroen; Reemer, Menno; van Kats, Ruud; Ozinga, Wim A; van der Linden, Giel T J; Schaminée, Joop H J; Siepel, Henk; Kleijn, David

    2014-12-01

    Evidence for declining populations of both wild and managed bees has raised concern about a potential global pollination crisis. Strategies to mitigate bee loss generally aim to enhance floral resources. However, we do not really know whether loss of preferred floral resources is the key driver of bee decline because accurate assessment of host plant preferences is difficult, particularly for species that have become rare. Here we examine whether population trends of wild bees in The Netherlands can be explained by trends in host plants, and how this relates to other factors such as climate change. We determined host plant preference of bee species using pollen loads on specimens in entomological collections that were collected before the onset of their decline, and used atlas data to quantify population trends of bee species and their host plants. We show that decline of preferred host plant species was one of two main factors associated with bee decline. Bee body size, the other main factor, was negatively related to population trend, which, because larger bee species have larger pollen requirements than smaller species, may also point toward food limitation as a key factor driving wild bee loss. Diet breadth and other potential factors such as length of flight period or climate change sensitivity were not important in explaining twentieth century bee population trends. These results highlight the species-specific nature of wild bee decline and indicate that mitigation strategies will only be effective if they target the specific host plants of declining species. PMID:25422416

  4. Nitric oxide control of cardiac function: is neuronal nitric oxide synthase a key component?

    PubMed Central

    Sears, Claire E; Ashley, Euan A; Casadei, Barbara

    2004-01-01

    Nitric oxide (NO) has been shown to regulate cardiac function, both in physiological conditions and in disease states. However, several aspects of NO signalling in the myocardium remain poorly understood. It is becoming increasingly apparent that the disparate functions ascribed to NO result from its generation by different isoforms of the NO synthase (NOS) enzyme, the varying subcellular localization and regulation of NOS isoforms and their effector proteins. Some apparently contrasting findings may have arisen from the use of non-isoform-specific inhibitors of NOS, and from the assumption that NO donors may be able to mimic the actions of endogenously produced NO. In recent years an at least partial explanation for some of the disagreements, although by no means all, may be found from studies that have focused on the role of the neuronal NOS (nNOS) isoform. These data have shown a key role for nNOS in the control of basal and adrenergically stimulated cardiac contractility and in the autonomic control of heart rate. Whether or not the role of nNOS carries implications for cardiovascular disease remains an intriguing possibility requiring future study. PMID:15306414

  5. Advanced Key Technologies for Hot Control Surfaces in Space Re- Entry Vehicles

    NASA Astrophysics Data System (ADS)

    Dogigli, Michael; Pradier, Alain; Tumino, Giorgio

    2002-01-01

    (1)MAN Technologie AG, D- 86153 Augsburg, Germany (2,3) ESA, 2200 Noordwijk ZH, The Netherlands Current space re-entry vehicles (e.g. X-38 vehicle 201, the prototype of the International Space Station's Crew Return Vehicle (CRV)) require advanced control surfaces (so called body flaps). Such control surfaces allow the design of smaller and lighter vehicles as well as faster re-entries (compared to the US Shuttle). They are designed as light-weight structures that need no metallic parts, need no mass or volume consuming heat sinks to protect critical components (e.g. bearings) and that can be operated at temperatures of more than 1600 "C in air transferring high mechanical loads (dynamic 40 kN, static 70 kN) at the same time. Because there is a need for CRV and also for Reusable Launch Vehicles (RLV) in future, the European Space Agency (ESA) felt compelled to establish a "Future European Space Transportation and Investigation Program,, (FESTIP) and a "General Support for Technology Program,, (GSTP). One of the main goals of these programs was to develop and qualify key-technologies that are able to master the above mentioned challenging requirements for advanced hot control surfaces and that can be applied for different vehicles. In 1996 MAN Technologie has started the development of hot control surfaces for small lifting bodies in the national program "Heiü Strukturen,,. One of the main results of this program was that especially the following CMC (Ceramic Matrix Composite) key technologies need to be brought up to space flight standard: Complex CMC Structures, CMC Bearings, Metal-to-CMC Joining Technologies, CMC Fasteners, Oxidation Protection Systems and Static and Dynamic Seals. MAN Technologie was contracted by ESA to continue the development and qualification of these key technologies in the frame of the FESTIP and the GSTP program. Development and qualification have successfully been carried out. The key technologies have been applied for the X-38 vehicle

  6. On the Factor Structure of the Beck Depression Inventory-II: G Is the Key

    ERIC Educational Resources Information Center

    Brouwer, Danny; Meijer, Rob R.; Zevalkink, Jolien

    2013-01-01

    The Beck Depression Inventory-II (BDI-II; Beck, Steer, & Brown, 1996) is intended to measure severity of depression, and because items represent a broad range of depressive symptoms, some multidimensionality exists. In recent factor-analytic studies, there has been a debate about whether the BDI-II can be considered as one scale or whether…

  7. Students' Understanding of Large Numbers as a Key Factor in Their Understanding of Geologic Time

    ERIC Educational Resources Information Center

    Cheek, Kim A.

    2012-01-01

    An understanding of geologic time is comprised of 2 facets. Events in Earth's history can be placed in relative and absolute temporal succession on a vast timescale. Rates of geologic processes vary widely, and some occur over time periods well outside human experience. Several factors likely contribute to an understanding of geologic time, one of…

  8. Key Factors in Smoking Cessation Intervention among 15-16-Year-Olds

    ERIC Educational Resources Information Center

    Heikkinen, Anna Maria; Broms, Ulla; Pitkaniemi, Janne; Koskenvuo, Markku; Meurman, Jukka

    2009-01-01

    The authors aimed to investigate factors associated with smoking cessation among adolescents after tobacco intervention. They examined smokers (n = 127) from one birth cohort (n = 545) in the city of Kotka in Finland. These smokers were randomized in 3 intervention groups the dentist (n = 44) and the school nurse (n = 42 groups), and a control…

  9. Cell fate control by pioneer transcription factors.

    PubMed

    Iwafuchi-Doi, Makiko; Zaret, Kenneth S

    2016-06-01

    Distinct combinations of transcription factors are necessary to elicit cell fate changes in embryonic development. Yet within each group of fate-changing transcription factors, a subset called 'pioneer factors' are dominant in their ability to engage silent, unmarked chromatin and initiate the recruitment of other factors, thereby imparting new function to regulatory DNA sequences. Recent studies have shown that pioneer factors are also crucial for cellular reprogramming and that they are implicated in the marked changes in gene regulatory networks that occur in various cancers. Here, we provide an overview of the contexts in which pioneer factors function, how they can target silent genes, and their limitations at regions of heterochromatin. Understanding how pioneer factors regulate gene expression greatly enhances our understanding of how specific developmental lineages are established as well as how cell fates can be manipulated. PMID:27246709

  10. Key recovery factors for the August 24, 2014, South Napa earthquake

    USGS Publications Warehouse

    Hudnut, Kenneth W.; Brocher, Thomas M.; Prentice, Carol S.; Boatwright, John; Brooks, Benjamin A.; Aagaard, Brad T.; Blair, James Luke; Fletcher, Joe B.; Erdem, Jemile E.; Wicks, Charles W., Jr.; Murray, Jessica R.; Pollitz, Fred F.; Langbein, John O.; Svarc, Jerry L.; Schwartz, David P.; Ponti, Daniel J.; Hecker, Suzanne; DeLong, Stephen B.; Rosa, Carla M.; Jones, Brenda; Lamb, Rynn; Rosinski, Anne M.; McCrink, Timothy P.; Dawson, Timothy E.; Seitz, Gordon G.; Rubin, Ron S.; Glennie, Craig; Hauser, Darren; Ericksen, Todd; Mardock, Dan; Hoirup, Don F.; Bray, Jonathan D.

    2014-01-01

    Through discussions between the Federal Emergency Management Agency (FEMA) and the U.S. Geological Survey (USGS) following the South Napa earthquake, it was determined that several key decision points would be faced by FEMA for which additional information should be sought and provided by USGS and its partners. This report addresses the four tasks that were agreed to. These tasks are (1) assessment of ongoing fault movement (called afterslip) especially in the Browns Valley residential neighborhood, (2) assessment of the shaking pattern in the downtown area of the City of Napa, (3) improvement of information on the fault hazards posed by the West Napa Fault System (record of past earthquakes and slip rate, for example), and (4) imagery acquisition and data processing to provide overall geospatial information support to FEMA.

  11. Oxidative stress--a key emerging impact factor in health, ageing, lifestyle and aesthetics.

    PubMed

    Kandola, K; Bowman, A; Birch-Machin, M A

    2015-12-01

    Oxidative stress is the resultant damage that arises due to redox imbalances, more specifically an increase in destructive free radicals and reduction in protection from antioxidants and the antioxidant defence pathways. Oxidation of lipids by reactive oxygen species (ROS) can damage cellular structures and result in premature cell death. At low levels, ROS-induced oxidative stress can be prevented through the action of antioxidants, however, when ROS are present in excess, inflammation and cytotoxicity eventually results leading to cellular oxidative stress damage. Increasing evidence for the role of oxidative stress in various diseases including neurological, dermatological, and cardiovascular diseases is now emerging. Mitochondria are the principal source (90%) of ROS in the cell, with superoxide radicals being generated when molecular oxygen is combined with free electrons. Given the key role of mitochondria in the generation of cellular oxidative stress it is worth considering this organelle and the process in more detail and to provide methods of intervention. PMID:26574299

  12. Planktonic foraminifera: factors controlling sinking speeds

    NASA Astrophysics Data System (ADS)

    Takahashi, Kozo; Be, Allan W. H.

    1984-12-01

    Sinking speeds of 330 specimens belonging to 10 extant species of planktonic foraminifera were determined in a sinking column device filled with 3°C seawater. The sinking speed is governed primarily by shell weight and presence/absence of spines. For example, preserved planktonic specimens of Orbulina universa, whose shell weight ranged from 2 to 21 μg, sank 122 to 583 m day -1, with a correlation coefficient of 0.92 on log-log scale. Progressive shell thickening during foraminiferal growth accounts for some of the higher sinking speeds. In addition, shells from sediment on the average sink about three times faster than shells (of equivalent size and species) of planktonic foraminifera collected in near-surface waters. These high values are in part due to the shells often being encrusted with clay and nannoplankton remains. In contrast, the sinking speeds of the spinose species are approximately 3-fold slower than those of the non-spinose species. Based on data from plankton tows, most planktonic foraminifera > 150 μm reach the mean ocean depth of 3800 m in 3 to 12 days depending upon shell weight and presence or absence of spines. Estimated Reynolds numbers range from 0.05 to 24.85 and most exceed a value of 0.5 which is an upper for limit Stokes' Law range, suggesting that foraminifera are out of Stokes' sinking range. The Reynolds number and drag coefficients are negatively well correlated, indicating that drag is one of the important controlling factors in the sinking regime. The presence of spines is significant in increasing drag, decreasing the Reynolds number, and hence reducing the sinking speed.

  13. Decision-directed automatic gain control for MAPSK systems. [M-ary Amplitude and Phase Shift Keying

    NASA Technical Reports Server (NTRS)

    Weber, W. J., III

    1974-01-01

    An automatic gain control (AGC) loop is presented for use with M-ary amplitude and phase shift keying (MAPSK) systems. The gain control amplifier is regulated by an error signal formed by the difference between the estimated amplitude level and the received amplitude level. The AGC performance is thus independent of the short-term average received signal energy. AGC loop analysis and simulation is presented for M-ary amplitude shift keying and quadrature amplitude shift keying. The AGC is shown to have a negligible degradation on the symbol probability of error for most practical cases. A generalized AGC for an arbitrary MAPSK system is presented.

  14. Sucrose is an early modulator of the key hormonal mechanisms controlling bud outgrowth in Rosa hybrida.

    PubMed

    Barbier, François; Péron, Thomas; Lecerf, Marion; Perez-Garcia, Maria-Dolores; Barrière, Quentin; Rolčík, Jakub; Boutet-Mercey, Stéphanie; Citerne, Sylvie; Lemoine, Remi; Porcheron, Benoît; Roman, Hanaé; Leduc, Nathalie; Le Gourrierec, José; Bertheloot, Jessica; Sakr, Soulaiman

    2015-05-01

    Sugar has only recently been identified as a key player in triggering bud outgrowth, while hormonal control of bud outgrowth is already well established. To get a better understanding of sugar control, the present study investigated how sugar availability modulates the hormonal network during bud outgrowth in Rosa hybrida. Other plant models, for which mutants are available, were used when necessary. Buds were grown in vitro to manipulate available sugars. The temporal patterns of the hormonal regulatory network were assessed in parallel with bud outgrowth dynamics. Sucrose determined bud entrance into sustained growth in a concentration-dependent manner. Sustained growth was accompanied by sustained auxin production in buds, and sustained auxin export in a DR5::GUS-expressing pea line. Several events occurred ahead of sucrose-stimulated bud outgrowth. Sucrose upregulated early auxin synthesis genes (RhTAR1, RhYUC1) and the auxin efflux carrier gene RhPIN1, and promoted PIN1 abundance at the plasma membrane in a pPIN1::PIN1-GFP-expressing tomato line. Sucrose downregulated both RwMAX2, involved in the strigolactone-transduction pathway, and RhBRC1, a repressor of branching, at an early stage. The presence of sucrose also increased stem cytokinin content, but sucrose-promoted bud outgrowth was not related to that pathway. In these processes, several non-metabolizable sucrose analogues induced sustained bud outgrowth in R. hybrida, Pisum sativum, and Arabidopsis thaliana, suggesting that sucrose was involved in a signalling pathway. In conclusion, we identified potential hormonal candidates for bud outgrowth control by sugar. They are central to future investigations aimed at disentangling the processes that underlie regulation of bud outgrowth by sugar. PMID:25873679

  15. Soil Surface Structure: A key factor for the degree of soil water repellency

    NASA Astrophysics Data System (ADS)

    Ahn, S.; Doerr, S. H.; Douglas, P.; Bryant, R.; Hamlett, C.; McHale, G.; Newton, M.; Shirtcliffe, N.

    2012-04-01

    Despite of considerable efforts, the degree of water repellency has not always been fully explained by chemical property of soil (termed hydrophobicity). That might be because the structure of a soil surface was not considered properly, which is another main factor determining the severity of soil water repellency. Surface structure has only recently been considered in soil science, whilst it has been paid attention for several decades in materials science due to its relevance to industrial applications. In this contribution, comparison of critical contact angles measured on different surface structures (made with glass beads, glass shards and beach sands) is presented and the effect of surface structure on manifestation of soil water repellency is discussed in terms of several different variables such as the individual particles shape, and areal and structural factors of the actual surface.

  16. Negative thinking: a key factor in depressive symptoms in Thai adolescents.

    PubMed

    Charoensuk, Sukjai

    2007-01-01

    Negative thinking, self-esteem, parental bonding, and everyday stressors are factors related to depressive symptoms in studies conducted in the United States, but they have been rarely explored in Thailand. An understanding of factors influencing depressive symptoms in Thai youth will lead to the development of interventions to decrease depressive symptoms among this age group. The purpose of this study was to examine the effects of parental bonding, everyday stressors, self-esteem, and negative thinking on depressive symptoms among Thai adolescents. A random sample of 812 high school students in Chon Buri, Thailand, participated in the study. The prevalence of depressive symptoms varied from 20-21% depending on the measures used. Negative thinking was the best predictor of depressive symptoms in Thai adolescents. Negative thinking also mediated the effects of parental bonding, everyday stressors, and self-esteem on depressive symptoms. PMID:17130007

  17. Key factors contributing to accident severity rate in construction industry in Iran: a regression modelling approach.

    PubMed

    Soltanzadeh, Ahmad; Mohammadfam, Iraj; Moghimbeigi, Abbas; Ghiasvand, Reza

    2016-03-01

    Construction industry involves the highest risk of occupational accidents and bodily injuries, which range from mild to very severe. The aim of this cross-sectional study was to identify the factors associated with accident severity rate (ASR) in the largest Iranian construction companies based on data about 500 occupational accidents recorded from 2009 to 2013. We also gathered data on safety and health risk management and training systems. Data were analysed using Pearson's chi-squared coefficient and multiple regression analysis. Median ASR (and the interquartile range) was 107.50 (57.24- 381.25). Fourteen of the 24 studied factors stood out as most affecting construction accident severity (p<0.05). These findings can be applied in the design and implementation of a comprehensive safety and health risk management system to reduce ASR. PMID:27092639

  18. K-factor greater than 1 - The key for stable amplifiers

    NASA Astrophysics Data System (ADS)

    Gutierrez, Ray

    1989-09-01

    A review is given of stability problems encountered with amplifiers, and attention is given to the K-factor, which is a measure of the oscillatory tendency of any network at a specific frequency and for the conditions represented by the particular S-parameter values. The K-factor equation is reviewed for both conditionally stable (K less than or equal to one) and unconditionally stable (K greater than one) networks, and the three different degrees of stability are outlined in a discussion of stability circles. In addition, a review is given of some circuit configurations that are used to improve amplifier performance at the expense of stability, and a quick alternative is presented for measuring amplifier stability over broad bandwidths using a scalar analyzer.

  19. A structured elicitation method to identify key direct risk factors for the management of natural resources.

    PubMed

    Smith, Michael; Wallace, Ken; Lewis, Loretta; Wagner, Christian

    2015-11-01

    The high level of uncertainty inherent in natural resource management requires planners to apply comprehensive risk analyses, often in situations where there are few resources. In this paper, we demonstrate a broadly applicable, novel and structured elicitation approach to identify important direct risk factors. This new approach combines expert calibration and fuzzy based mathematics to capture and aggregate subjective expert estimates of the likelihood that a set of direct risk factors will cause management failure. A specific case study is used to demonstrate the approach; however, the described methods are widely applicable in risk analysis. For the case study, the management target was to retain all species that characterise a set of natural biological elements. The analysis was bounded by the spatial distribution of the biological elements under consideration and a 20-year time frame. Fourteen biological elements were expected to be at risk. Eleven important direct risk factors were identified that related to surrounding land use practices, climate change, problem species (e.g., feral predators), fire and hydrological change. In terms of their overall influence, the two most important risk factors were salinisation and a lack of water which together pose a considerable threat to the survival of nine biological elements. The described approach successfully overcame two concerns arising from previous risk analysis work: (1) the lack of an intuitive, yet comprehensive scoring method enabling the detection and clarification of expert agreement and associated levels of uncertainty; and (2) the ease with which results can be interpreted and communicated while preserving a rich level of detail essential for informed decision making. PMID:27441228

  20. Key factors for a successful implementation of personalized e-health services.

    PubMed

    Griebel, Lena; Sedlmayr, Brita; Prokosch, Hans-Ulrich; Criegee-Rieck, Manfred; Sedlmayr, Martin

    2013-01-01

    Personalized e-health services hold many promises, e.g. the improvement of health care quality or the reduction of costs. However, such services can't tap their full potential if they will not be used. That's why it is essential to understand what brings potential users to accept them. In the literature many acceptance models exist that predict the usage of innovations, but none of them specifically refers to the adoption of e-health services. Therefore we combined the Unified Theory of Acceptance and Use of Technology (UTAUT) and the e-health literacy concept and enhanced the resulting model with additional factors. MEDLINE® was searched; 75 studies were included for final analysis. Apart from the UTAUT variables and e-health literacy, 10 additional factors were identified: anxiety, trust, attitude toward using, computer self-efficacy, perceived system quality, search strategy, user's condition, health specific knowledge, Internet dependency and satisfaction with medical care. Future research will include the devolvement of an instrument for assessing these factors and testing the initial research model in an international context. PMID:23920739

  1. Comparative “-omics” in Mycoplasma pneumoniae Clinical Isolates Reveals Key Virulence Factors

    PubMed Central

    Lluch-Senar, Maria; Cozzuto, Luca; Cano, Jaime; Delgado, Javier; Llórens-Rico, Verónica; Pereyre, Sabine; Bebear, Cécile; Serrano, Luis

    2015-01-01

    The human respiratory tract pathogen M. pneumoniae is one of the best characterized minimal bacterium. Until now, two main groups of clinical isolates of this bacterium have been described (types 1 and 2), differing in the sequence of the P1 adhesin gene. Here, we have sequenced the genomes of 23 clinical isolates of M. pneumoniae. Studying SNPs, non-synonymous mutations, indels and genome rearrangements of these 23 strains and 4 previously sequenced ones, has revealed new subclasses in the two main groups, some of them being associated with the country of isolation. Integrative analysis of in vitro gene essentiality and mutation rates enabled the identification of several putative virulence factors and antigenic proteins; revealing recombination machinery, glycerol metabolism and peroxide production as possible factors in the genetics and physiology of these pathogenic strains. Additionally, the transcriptomes and proteomes of two representative strains, one from each of the two main groups, have been characterized to evaluate the impact of mutations on RNA and proteins levels. This study has revealed that type 2 strains show higher expression levels of CARDS toxin, a protein recently shown to be one of the major factors of inflammation. Thus, we propose that type 2 strains could be more toxigenic than type 1 strains of M. pneumoniae. PMID:26335586

  2. Academic mobility as a key factor of quality assurance in tertiary education

    NASA Astrophysics Data System (ADS)

    Voroshilova, Anna A.

    2015-01-01

    Academic mobility of both faculty and students forms a critical element of the international dimension of higher education and is one of the most important factors of quality assurance of higher education institutions worldwide. Internationalization and globalization of Russian higher education system is having one of the major impacts on the quality management and assurance. Faculty and student mobility figures are now one of the core factors for obtaining state accreditation for Russian universities as well as an important indicator showing the university success and prestige. The aim of the paper is a closer look at the perspectives and results of the academic mobility, the factors stimulating and discouraging mobility, and the outcomes of the mobility influencing the education in Russian universities. Siberian State Aerospace University has had more than 10 years experience in organizing student mobility. Most of the problems in carrying out international activities are common for the whole Russia but still there are some peculiarities featuring technical universities situated in the centre of Russia.

  3. Is Personality a Key Predictor of Missing Study Data? An Analysis From a Randomized Controlled Trial

    PubMed Central

    Jerant, Anthony; Chapman, Benjamin P.; Duberstein, Paul; Franks, Peter

    2009-01-01

    PURPOSE Little is known regarding the effects of psychological factors on data collection in research studies. We examined whether Five Factor Model (FFM) personality factors—Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness—predicted missing data in a randomized controlled trial (RCT). METHODS Individuals (N = 415) aged 40 years and older with various chronic conditions, plus basic activity impairment, depressive symptoms, or both, were recruited from a primary care network and enrolled in a 6-week RCT of an illness self-management intervention, delivered by means of home visits or telephone calls or usual care. Random effects logistic regression modeling was used to examine whether FFM factors predicted missing illness management self-efficacy data at any scheduled follow-up (2, 4, and 6 weeks, and 6 and 12 months), controlling for disease burden, study arm, and sociodemographic characteristics. RESULTS Across all follow-up points, the missing data rate was 4.5%. Higher levels of Openness (adjusted odds ratio [AOR] for 1-SD increase = 0.24; 95% CI, 0.12–0.46; P <.001), Agreeableness (AOR = 0.29; CI 0.14–0.60; P=.001), and Conscientiousness (AOR = 0.24; CI 0.15–0.50; P <.001) were independently associated with fewer missing data. Accuracy of the missing data prediction model increased when personality variables were added (change in area under the receiver operating characteristic curve from 0.71 to 0.77; χ21=6.6; P=.01). CONCLUSIONS Personality was a powerful predictor of missing study data in this RCT. Assessing personality could inform efforts to enhance data completion and adjust analyses for bias caused by missing data. PMID:19273870

  4. Interferon regulatory factor 3 is a key regulation factor for inducing the expression of SAMHD1 in antiviral innate immunity

    PubMed Central

    Yang, Shen; Zhan, Yuan; Zhou, Yanjun; Jiang, Yifeng; Zheng, Xuchen; Yu, Lingxue; Tong, Wu; Gao, Fei; Li, Liwei; Huang, Qinfeng; Ma, Zhiyong; Tong, Guangzhi

    2016-01-01

    SAMHD1 is a type I interferon (IFN) inducible host innate immunity restriction factor that inhibits an early step of the viral life cycle. The underlying mechanisms of SAMHD1 transcriptional regulation remains elusive. Here, we report that inducing SAMHD1 upregulation is part of an early intrinsic immune response via TLR3 and RIG-I/MDA5 agonists that ultimately induce the nuclear translocation of the interferon regulation factor 3 (IRF3) protein. Further studies show that IRF3 plays a major role in upregulating endogenous SAMHD1 expression in a mechanism that is independent of the classical IFN-induced JAK-STAT pathway. Both overexpression and activation of IRF3 enhanced the SAMHD1 promoter luciferase activity, and activated IRF3 was necessary for upregulating SAMHD1 expression in a type I IFN cascade. We also show that the SAMHD1 promoter is a direct target of IRF3 and an IRF3 binding site is sufficient to render this promoter responsive to stimulation. Collectively, these findings indicate that upregulation of endogenous SAMHD1 expression is attributed to the phosphorylation and nuclear translocation of IRF3 and we suggest that type I IFN induction and induced SAMHD1 expression are coordinated. PMID:27411355

  5. Key Factors and Timing Patterns in the Tennis Forehand of Different Skill Levels

    PubMed Central

    Landlinger, Johannes; Lindinger, Stefan; Stöggl, Thomas; Wagner, Herbert; Müller, Erich

    2010-01-01

    The main purpose of the present study was to quantify and compare selected kinematic variables and their timing during the tennis forehand of different skill levels. An eight-camera 400 Hz, Vicon motion analysis system recorded kinematic data of six ATP- professionals (elite) and seven high performance (HP) players when shots were played cross court and down the line. Timing of the maximum angles, linear and angular velocities was measured prior to and after impact. A total of twelve strokes per subject were analyzed from the beginning to the end of horizontal racquet movement. Significant differences (p < 0.01) and large effect sizes were observed between elite and HP players in the timing of maximum pelvis (-0.075 ± 0.008 vs. -0.093 ± 0.012 s) and trunk angular velocities (-0.057 ± 0.004 vs. -0.075 ± 0.011 s) before impact. The elite group showed a tendency (p < 0.05) towards higher peak horizontal shoulder (3.0 ± 0.4 vs. 2.5 ± 0.4 m·s-1) and racquet velocities (33.1 ± 2.4 vs. 31.1 ± 1.9 m·s-1) compared to the HP players. Depending on the situation (cross court vs. down the line), different peak hip, racquet and separation angles were found for both groups. Similar peak values were detected between groups for maximum angular velocities and displacement of key variables that had been selected for analysis. The findings of this study can be vital for successful player development, improved performance or injury prevention. The later occurrence of maximum angular pelvis and trunk rotations were the main reasons for the tendency towards higher horizontal shoulder and racquet velocities in the elite group. Key points Different timing of maximum angular pelvis and trunk rotations separated the elite from the high performance players. The elite group tended to reach higher horizontal shoulder and racquet velocities than the high performance group. In addition to maximum angular velocities, maximum racquet, shoulder, and hip alignment angles were similar

  6. Key factors limiting carbon nanotube yarn strength: exploring processing-structure-property relationships.

    PubMed

    Beese, Allison M; Wei, Xiaoding; Sarkar, Sourangsu; Ramachandramoorthy, Rajaprakash; Roenbeck, Michael R; Moravsky, Alexander; Ford, Matthew; Yavari, Fazel; Keane, Denis T; Loutfy, Raouf O; Nguyen, SonBinh T; Espinosa, Horacio D

    2014-11-25

    Studies of carbon nanotube (CNT) based composites have been unable to translate the extraordinary load-bearing capabilities of individual CNTs to macroscale composites such as yarns. A key challenge lies in the lack of understanding of how properties of filaments and interfaces across yarn hierarchical levels govern the properties of macroscale yarns. To provide insight required to enable the development of superior CNT yarns, we investigate the fabrication-structure-mechanical property relationships among CNT yarns prepared by different techniques and employ a Monte Carlo based model to predict upper bounds on their mechanical properties. We study the correlations between different levels of alignment and porosity and yarn strengths up to 2.4 GPa. The uniqueness of this experimentally informed modeling approach is the model's ability to predict when filament rupture or interface sliding dominates yarn failure based on constituent mechanical properties and structural organization observed experimentally. By capturing this transition and predicting the yarn strengths that could be obtained under ideal fabrication conditions, the model provides critical insights to guide future efforts to improve the mechanical performance of CNT yarn systems. This multifaceted study provides a new perspective on CNT yarn design that can serve as a foundation for the development of future composites that effectively exploit the superior mechanical performance of CNTs. PMID:25353651

  7. Crystallographic orientation and electrode nature are key factors for electric current generation by Geobacter sulfurreducens.

    PubMed

    Maestro, Beatriz; Ortiz, Juan M; Schrott, Germán; Busalmen, Juan P; Climent, Víctor; Feliu, Juan M

    2014-08-01

    We have investigated the influence of electrode material and crystallographic structure on electron transfer and biofilm formation of Geobacter sulfurreducens. Single-crystal gold-Au(110), Au(111), Au(210)-and platinum-Pt(100), Pt(110), Pt(111), Pt(210)-electrodes were tested and compared to graphite rods. G. sulfurreducens electrochemically interacts with all these materials with different attachment kinetics and final current production, although redox species involved in the electron transfer to the anode are virtually the same in all cases. Initial bacterial colonization was fastest on graphite up to the monolayer level, whereas gold electrodes led to higher final current densities. Crystal geometry was shown to have an important influence, with Au(210) sustaining a current density of up to 1442±101μAcm(-2) at the steady state, over Au(111) with 961±94μAcm(-2) and Au(110) with 944±89μAcm(-2). On the other hand, the platinum electrodes displayed the lowest performances, including Pt(210). Our results indicate that both crystal geometry and electrode material are key parameters for the efficient interaction of bacteria with the substrate and should be considered for the design of novel materials and microbial devices to optimize energy production. PMID:24642203

  8. Key Factors Influencing Rates of Heterotrophic Sulfate Reduction in Hydrothermal Massive Sulfide Deposits

    NASA Astrophysics Data System (ADS)

    Frank, K. L.; Rogers, K. L.; Rogers, D.; Johnston, D. T.; Girguis, P. R.

    2015-12-01

    Hydrothermal vents are thermally and geochemically dynamic habitats, and the organisms therein are subject to steep fluctuations in temperature and chemistry. To date, the influence of these environmental dynamics on microbial sulfate reduction has not been well constrained. Here, via multivariate experiments, we evaluate the effects of key environmental variables (temperature, pH, H2S, SO42-, DOC) on sulfate reduction rates and metabolic energy yields in a hydrothermal flange recovered from the Grotto vent in the Main Endeavor Field, Juan de Fuca ridge. Sulfate reduction was measured in batch reactions across a range of physico-chemical conditions. Temperature and pH were the strongest stimuli and maximum sulfate reduction rates were observed at 50°C and pH 6, suggesting that the in situ community of sulfate reducing organisms at Grotto may be most active in a slightly acidic and moderate thermal/chemical regime. At pH 4, sulfate reduction rates increased with sulfide concentrations most likely due to the mitigation of metal toxicity. While substrate concentrations also influenced sulfate reduction rates, energy-rich conditions muted the effect of metabolic energetics on sulfate reduction rates. We posit that variability in sulfate reduction rates reflect the response of the active microbial consortia to environmental constraints on in situ microbial physiology, toxicity, and the type and extent of energy limitation. These experiments help to constrain models of the spatial contribution of heterotrophic sulfate within the complex gradients inherent to hydrothermal deposits.

  9. Krüppel-like Factor 15 (KLF15) Is a Key Regulator of Podocyte Differentiation*

    PubMed Central

    Mallipattu, Sandeep K.; Liu, Ruijie; Zheng, Feng; Narla, Goutham; Ma'ayan, Avi; Dikman, Steven; Jain, Mukesh K.; Saleem, Moin; D'Agati, Vivette; Klotman, Paul; Chuang, Peter Y.; He, John C.

    2012-01-01

    Podocyte injury resulting from a loss of differentiation is the hallmark of many glomerular diseases. We previously showed that retinoic acid (RA) induces podocyte differentiation via stimulation of the cAMP pathway. However, many podocyte maturity markers lack binding sites for RA-response element or cAMP-response element (CREB) in their promoter regions. We hypothesized that transcription factors induced by RA and downstream of CREB mediate podocyte differentiation. We performed microarray gene expression studies in human podocytes treated with and without RA to identify differentially regulated genes. In comparison with known CREB target genes, we identified Krüppel-like factor 15 (KLF15), a kidney-enriched nuclear transcription factor, that has been previously shown to mediate cell differentiation. We confirmed that RA increased KLF15 expression in both murine and human podocytes. Overexpression of KLF15 stimulated expression of differentiation markers in both wild-type and HIV-1-infected podocytes. Also, KLF15 binding to the promoter regions of nephrin and podocin was increased in RA-treated podocytes. Although KLF15−/− mice at base line had minimal phenotype, lipopolysaccharide- or adriamycin-treated KLF15−/− mice had a significant increase in proteinuria and podocyte foot process effacement with a reduction in the expression of podocyte differentiation markers as compared with the wild-type treated mice. Finally, KLF15 expression was reduced in glomeruli isolated from HIV transgenic mice as well as in kidney biopsies from patients with HIV-associated nephropathy and idiopathic focal segmental glomerulosclerosis. These results indicate a critical role of KLF15 in mediating podocyte differentiation and in protecting podocytes against injury. PMID:22493483

  10. Macrophage Migration Inhibitory Factor (MIF): A Key Player in Protozoan Infections

    PubMed Central

    de Dios Rosado, Juan; Rodriguez-Sosa, Miriam

    2011-01-01

    Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine produced by the pituitary gland and multiple cell types, including macrophages (Mø), dendritic cells (DC) and T-cells. Upon releases MIF modulates the expression of several inflammatory molecules, such as TNF-α, nitric oxide and cyclooxygenase 2 (COX-2). These important MIF characteristics have prompted investigators to study its role in parasite infections. Several reports have demonstrated that MIF plays either a protective or deleterious role in the immune response to different pathogens. Here, we review the role of MIF in the host defense response to some important protozoan infections. PMID:22110378

  11. Deterministic Polynomial Time Equivalence between Factoring and Key-Recovery Attack on Takagi's RSA

    NASA Astrophysics Data System (ADS)

    Kunihiro, Noboru; Kurosawa, Kaoru

    For RSA, May showed a deterministic polynomial time equivalence of computing d to factoring N(=pq). On the other hand, Takagi showed a variant of RSA such that the decryption algorithm is faster than the standard RSA, where N=prq while ed=1 mod (p-1)(q-1). In this paper, we show that a deterministic polynomial time equivalence also holds in this variant. The coefficient matrix T to which LLL algorithm is applied is no longer lower triangular, and hence we develop a new technique to overcome this problem.

  12. Biometrics based key management of double random phase encoding scheme using error control codes

    NASA Astrophysics Data System (ADS)

    Saini, Nirmala; Sinha, Aloka

    2013-08-01

    In this paper, an optical security system has been proposed in which key of the double random phase encoding technique is linked to the biometrics of the user to make it user specific. The error in recognition due to the biometric variation is corrected by encoding the key using the BCH code. A user specific shuffling key is used to increase the separation between genuine and impostor Hamming distance distribution. This shuffling key is then further secured using the RSA public key encryption to enhance the security of the system. XOR operation is performed between the encoded key and the feature vector obtained from the biometrics. The RSA encoded shuffling key and the data obtained from the XOR operation are stored into a token. The main advantage of the present technique is that the key retrieval is possible only in the simultaneous presence of the token and the biometrics of the user which not only authenticates the presence of the original input but also secures the key of the system. Computational experiments showed the effectiveness of the proposed technique for key retrieval in the decryption process by using the live biometrics of the user.

  13. The Grp170 nucleotide exchange factor executes a key role during ERAD of cellular misfolded clients

    PubMed Central

    Inoue, Takamasa; Tsai, Billy

    2016-01-01

    When a protein misfolds in the endoplasmic reticulum (ER), it retrotranslocates to the cytosol and is degraded by the proteasome via a pathway called ER-associated degradation (ERAD). To initiate ERAD, ADP-BiP is often recruited to the misfolded client, rendering it soluble and translocation competent. How the misfolded client is subsequently released from BiP so that it undergoes retrotranslocation, however, remains enigmatic. Here we demonstrate that the ER-resident nucleotide exchange factor (NEF) Grp170 plays an important role during ERAD of the misfolded glycosylated client null Hong Kong (NHK). As a NEF, Grp170 triggers nucleotide exchange of BiP to generate ATP-BiP. ATP-BiP disengages from NHK, enabling it to retrotranslocate to the cytosol. We demonstrate that Grp170 binds to Sel1L, an adapter of the transmembrane Hrd1 E3 ubiquitin ligase postulated to be the retrotranslocon, and links this interaction to Grp170’s function during ERAD. More broadly, Grp170 also promotes degradation of the nonglycosylated transthyretin (TTR) D18G misfolded client. Our findings thus establish a general function of Grp170 during ERAD and suggest that positioning this client-release factor at the retrotranslocation site may afford a mechanism to couple client release from BiP and retrotranslocation. PMID:27030672

  14. Identifying Key Factors in Homeowner's Adoption of Water Quality Best Management Practices

    NASA Astrophysics Data System (ADS)

    Brehm, Joan M.; Pasko, Danielle K.; Eisenhauer, Brian W.

    2013-07-01

    The recognition of the significance of the residential environment in contributing to non-point source (NPS) pollution and the inherently dispersed nature of NPS pollution itself that presents significant challenges to effective regulation has led to the creation and dissemination of best management practices (BMPs) that can reduce the impacts of NPS pollution (Environmental Protection Agency US, Protecting water quality from urban runoff, http://www.epa.gov/npdes/pubs/nps_urban-facts_final.pdf, 2003). However, very few studies have examined the factors that influence the adoption of BMPs by residential homeowners, despite the fact that residential environments have been identified as one of the most significant contributors to NPS pollution. Given this need, the purpose of this project was to explore how demographic and knowledge-based factors predict adoption of residential BMPs in an urbanizing watershed in Northern Illinois using statistical analyses of survey data collected as part of a watershed planning process. The findings indicate that broad knowledge of BMPs is the strongest predictor of use for a specific BMP. Knowledge of BMPs is strongly correlated with their use, which reinforces the need for educational programs, even among those assumed to be knowledgeable about BMPs.

  15. Power factor control system for ac induction motors

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (Inventor)

    1981-01-01

    A power control circuit for an induction motor is disclosed in which a servo loop is used to control power input by controlling the power factor of motor operation. The power factor is measured by summing the voltage and current derived square wave signals.

  16. Key Factors Influencing Rates of Heterotrophic Sulfate Reduction in Active Seafloor Hydrothermal Massive Sulfide Deposits

    PubMed Central

    Frank, Kiana L.; Rogers, Karyn L.; Rogers, Daniel R.; Johnston, David T.; Girguis, Peter R.

    2015-01-01

    Hydrothermal vents are thermally and geochemically dynamic habitats, and the organisms therein are subject to steep gradients in temperature and chemistry. To date, the influence of these environmental dynamics on microbial sulfate reduction has not been well constrained. Here, via multivariate experiments, we evaluate the effects of key environmental variables (temperature, pH, H2S, SO42−, DOC) on sulfate reduction rates and metabolic energy yields in material recovered from a hydrothermal flange from the Grotto edifice in the Main Endeavor Field, Juan de Fuca Ridge. Sulfate reduction was measured in batch reactions across a range of physico-chemical conditions. Temperature and pH were the strongest stimuli, and maximum sulfate reduction rates were observed at 50°C and pH 6, suggesting that the in situ community of sulfate-reducing organisms in Grotto flanges may be most active in a slightly acidic and moderate thermal/chemical regime. At pH 4, sulfate reduction rates increased with sulfide concentrations most likely due to the mitigation of metal toxicity. While substrate concentrations also influenced sulfate reduction rates, energy-rich conditions muted the effect of metabolic energetics on sulfate reduction rates. We posit that variability in sulfate reduction rates reflect the response of the active microbial consortia to environmental constraints on in situ microbial physiology, toxicity, and the type and extent of energy limitation. These experiments help to constrain models of the spatial contribution of heterotrophic sulfate reduction within the complex gradients inherent to seafloor hydrothermal deposits. PMID:26733984

  17. Hiring and Retention: Key Factors in Increasing Gender Diversity in the Geosciences

    NASA Astrophysics Data System (ADS)

    Holmes, M.; O'Connell, S.; Frey, C.

    2004-12-01

    Graduation and hiring data of geoscientists over the last ten years indicate that the largest leak in the academic pipeline for women geoscientists is at hiring into tenure-track positions. Anecdotal explanations for this leak generally cite a lack of females in the applicant pool, but women in tenure-track positions anecdotally cite a lack of family-friendly practices by academic departments. Both ideas are currently being tested via surveys of geoscience departments. Is there a way to attract more women to the field to increase the applicant pool? Results of focus groups of geoscientists indicate that both men and women are attracted into the field of geosciences by the same types of events: over one-third became a geoscientist by randomly walking into an undergraduate class and finding themselves captivated by the topic and/or a dynamic instructor. The subject matter itself attracts another one-fourth, and family members encourage another one-fifth of geoscientists to initially enter the field. Slightly more women cite the first attractor of undergraduate class, but the principal draw for our future workforce, male and female, is good instruction of freshman courses. Retention of women in academia is another key issue. The proportion that considers leaving after working towards one or more degrees is highly skewed by gender: one-half of female and only one-third of male geoscientists considered leaving the field at some time in their career. The reasons for considering leaving also differ by gender. Males cite financial issues, including an uncertain job market. Females cite two principal reasons for considering leaving: family issues and difficulties with a graduate advisor. Strategies currently exist for "family issues", including stop-the-clock (of tenure for family needs), assignment shift, on-campus daycare facilities, and unflinching administrative support for such practices. Graduate advising is a learnable skill, and more attention needs to be paid to

  18. Key Factors Influencing Rates of Heterotrophic Sulfate Reduction in Active Seafloor Hydrothermal Massive Sulfide Deposits.

    PubMed

    Frank, Kiana L; Rogers, Karyn L; Rogers, Daniel R; Johnston, David T; Girguis, Peter R

    2015-01-01

    Hydrothermal vents are thermally and geochemically dynamic habitats, and the organisms therein are subject to steep gradients in temperature and chemistry. To date, the influence of these environmental dynamics on microbial sulfate reduction has not been well constrained. Here, via multivariate experiments, we evaluate the effects of key environmental variables (temperature, pH, H2S, [Formula: see text], DOC) on sulfate reduction rates and metabolic energy yields in material recovered from a hydrothermal flange from the Grotto edifice in the Main Endeavor Field, Juan de Fuca Ridge. Sulfate reduction was measured in batch reactions across a range of physico-chemical conditions. Temperature and pH were the strongest stimuli, and maximum sulfate reduction rates were observed at 50°C and pH 6, suggesting that the in situ community of sulfate-reducing organisms in Grotto flanges may be most active in a slightly acidic and moderate thermal/chemical regime. At pH 4, sulfate reduction rates increased with sulfide concentrations most likely due to the mitigation of metal toxicity. While substrate concentrations also influenced sulfate reduction rates, energy-rich conditions muted the effect of metabolic energetics on sulfate reduction rates. We posit that variability in sulfate reduction rates reflect the response of the active microbial consortia to environmental constraints on in situ microbial physiology, toxicity, and the type and extent of energy limitation. These experiments help to constrain models of the spatial contribution of heterotrophic sulfate reduction within the complex gradients inherent to seafloor hydrothermal deposits. PMID:26733984

  19. Maternal effects and range expansion: a key factor in a dynamic process?

    PubMed Central

    Duckworth, Renée A.

    2009-01-01

    generated in newly colonized populations. More generally, these results suggest that, as a key source of variation in colonizing phenotypes, maternal effects are of crucial importance for understanding the dynamics of range expansion. PMID:19324612

  20. LOOP- SIMULATION OF THE AUTOMATIC FREQUENCY CONTROL SUBSYSTEM OF A DIFFERENTIAL MINIMUM SHIFT KEYING RECEIVER

    NASA Technical Reports Server (NTRS)

    Davarian, F.

    1994-01-01

    The LOOP computer program was written to simulate the Automatic Frequency Control (AFC) subsystem of a Differential Minimum Shift Keying (DMSK) receiver with a bit rate of 2400 baud. The AFC simulated by LOOP is a first order loop configuration with a first order R-C filter. NASA has been investigating the concept of mobile communications based on low-cost, low-power terminals linked via geostationary satellites. Studies have indicated that low bit rate transmission is suitable for this application, particularly from the frequency and power conservation point of view. A bit rate of 2400 BPS is attractive due to its applicability to the linear predictive coding of speech. Input to LOOP includes the following: 1) the initial frequency error; 2) the double-sided loop noise bandwidth; 3) the filter time constants; 4) the amount of intersymbol interference; and 5) the bit energy to noise spectral density. LOOP output includes: 1) the bit number and the frequency error of that bit; 2) the computed mean of the frequency error; and 3) the standard deviation of the frequency error. LOOP is written in MS SuperSoft FORTRAN 77 for interactive execution and has been implemented on an IBM PC operating under PC DOS with a memory requirement of approximately 40K of 8 bit bytes. This program was developed in 1986.

  1. Syntactic Computation in the Human Brain: The Degree of Merger as a Key Factor

    PubMed Central

    Ohta, Shinri; Fukui, Naoki; Sakai, Kuniyoshi L.

    2013-01-01

    Our goal of this study is to characterize the functions of language areas in most precise terms. Previous neuroimaging studies have reported that more complex sentences elicit larger activations in the left inferior frontal gyrus (L. F3op/F3t), although the most critical factor still remains to be identified. We hypothesize that pseudowords with grammatical particles and morphosyntactic information alone impose a construction of syntactic structures, just like normal sentences, and that “the Degree of Merger” (DoM) in recursively merged sentences parametrically modulates neural activations. Using jabberwocky sentences with distinct constructions, we fitted various parametric models of syntactic, other linguistic, and nonlinguistic factors to activations measured with functional magnetic resonance imaging. We demonstrated that the models of DoM and “DoM+number of Search (searching syntactic features)” were the best to explain activations in the L. F3op/F3t and supramarginal gyrus (L. SMG), respectively. We further introduced letter strings, which had neither lexical associations nor grammatical particles, but retained both matching orders and symbol orders of sentences. By directly contrasting jabberwocky sentences with letter strings, localized activations in L. F3op/F3t and L. SMG were indeed independent of matching orders and symbol orders. Moreover, by using dynamic causal modeling, we found that the model with a inhibitory modulatory effect for the bottom-up connectivity from L. SMG to L. F3op/F3t was the best one. For this best model, the top-down connection from L. F3op/F3t to L. SMG was significantly positive. By using diffusion-tensor imaging, we confirmed that the left dorsal pathway of the superior longitudinal and arcuate fasciculi consistently connected these regions. Lastly, we established that nonlinguistic order-related and error-related factors significantly activated the right (R.) lateral premotor cortex and R. F3op/F3t, respectively

  2. KEY FACTORS THAT INFLUENCE THE PERFORMANCE PROPERTIES OF ARP/MCU SALTSTONE MIXES

    SciTech Connect

    Harbour, J.; Edwards, T.; Williams, V.

    2009-10-05

    At the Saltstone Production Facility (SPF), decontaminated salt solution (DSS) is combined with premix (a cementitious mixture of portland cement (PC), blast furnace slag (BFS) and Class F fly ash (FA)) in a Readco mixer to produce fresh (uncured) Saltstone. After transfer to the Saltstone Disposal Facility (SDF) the hydration reactions initiated during the contact of the premix and salt solution continue during the curing period to produce the hardened waste form product. The amount of heat generated from hydration and the resultant temperature increase in the vaults depend on the composition of the decontaminated salt solution being dispositioned as well as the grout formulation (mix design). This report details the results from Task 3 of the Saltstone Variability Study for FY09 which was performed to identify, and quantify when possible, those factors that drive the performance properties of the projected ARP/MCU Batches. A baseline ARP/MCU mix (at 0.60 water to cementitious materials (w/cm) ratio) was established and consisted of the normal premix composition and a salt solution that was an average of the projected compositions of the last three ARP/MCU batches developed by T. A. Le. This task introduced significant variation in (1) wt % slag, w/cm ratio, and wt % portland cement about the baseline mix and (2) the temperature of curing in order to better assess the dependence of the performance properties on these factors. Two separate campaigns, designated Phase 10 and Phase 11, were carried out under Task 3. Experimental designs and statistical analyses were used to search for correlation among properties and to develop linear models to predict property values based on factors such as w/cm ratio, slag concentration, and portland cement concentration. It turns out that the projected salt compositions contained relatively high amounts of aluminate (0.22 M) even though no aluminate was introduced due to caustic aluminate removal from High Level Waste. Previous

  3. "Population is key factor in environmental degradation," Parliamentarian conference on ocean life declares.

    PubMed

    1995-01-01

    The Asian Forum of Parliamentarians on Population and Development (AFPPD)--Malaysia organized an international conference entitled "Ocean. Our Lifeline," which was held November 2-5, 1995, in Kuala Lumpur. The conference adopted a declaration that calls upon countries to address population growth, recognizing the central role of population pressure in environmental degradation, particularly with regard to the ocean. Parliamentarians were urged to develop and implement strategies to control pollution. The conference was attended by parliamentarians from Australia, China, India, Korea, Malaysia, Mongolia, New Zealand, Papua New Guinea, the Philippines, Singapore, Thailand, and the United States. AFPPD was represented by executive director Shiv Khare. PMID:12320069

  4. Control of canine rabies in developing countries: key features and animal welfare implications.

    PubMed

    Aréchiga Ceballos, N; Karunaratna, D; Aguilar Setién, A

    2014-04-01

    Over 90% of human deaths from rabies worldwide are caused by dog bites. Mass vaccination, along with the effective control of dog populations, has been used successfully in industrialised countries to control this disease. A lower success rate in developing countries is due to a number of factors, including vaccination campaigns that do not cover a sufficient number of animals or reach all communities, and a wide biodiversity that increases the number of reservoirs of the rabies virus. Educational programmes are needed, which focus on the commitment involved when acquiring a domestic animal, stating clearly what is required to provide it with a good quality of life. New technologies developed in the industrialised world will not always be successful in less developed countries. Approaches must be adapted to the particular conditions in each country, taking cultural and socio-economic issues into account. Authorities must promote research on dog population dynamics, the development of non-invasive methods to control dog populations and the most efficient, stable and low-cost options for vaccination. Under the One Health model, it is hoped that dog-transmitted human rabies will be accorded high priority as a zoonosis by human health authorities, international authorities and donor agencies to support ambitious eradication goals, particularly those being set in South-East Asia. Well-designed and adequately resourced vaccination programmes, based on the World Organisation for Animal Health (OIE) guidelines, will have significant animal welfare benefits, due to the availability of improved vaccines (in terms of efficacy, duration of immunity, ease of administration and lower cost), advances in dog population management and the more widespread implementation of the OIE Guidelines on Stray Dog Control. Animal welfare benefits include not only the elimination of pain and suffering caused by the clinical disease itself, but also the avoidance of the indirect impact of

  5. Factors controlling inter- and intramodel variability in global mean OH

    NASA Astrophysics Data System (ADS)

    Murray, L. T.; Fiore, A. M.; Shindell, D. T.

    2013-12-01

    Recent ensemble simulations of the 16 models of the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) show that there are large differences between models in global mean OH and its temporal evolution, even with the use of identical anthropogenic emission inventories. We find global mean OH in each individual ACCMIP model to linearly respond to convolved changes in tropospheric ozone photolysis frequencies, water vapor concentrations, and the ratio of reactive nitrogen to reactive carbon emissions. However, the ensemble members show a spread in both the slope and offset of these individual linear relationships. We present a series of sensitivity simulations using the GEOS-Chem chemical transport model driven by MERRA reanalysis fields and the ACCMIP/MACCity (Monitoring Atmospheric Composition & Climate/City Zen) emissions for 1980-2010 to diagnose potential factors that may be driving differences between the different ACCMIP models. We examine in particular the role of different gas-phase and heterogeneous chemical mechanisms, the spatial and temporal distribution of mean emissions, and the implementation of natural emissions (e.g., lightning, biogenic). Determining the key factors leading to the model differences in OH is a critical step to guide future efforts for identifying observation-based constraints for processes controlling OH variability.

  6. Study on the Key Factor Parameters to Increase Productivity in Construction and Manufacturing Industries.

    NASA Astrophysics Data System (ADS)

    Almazyed, K.; Alaswad, A.; Olabi, A. G.

    2016-02-01

    Proper management of human and non-human resources in construction and manufacturing projects can give-in considerable savings in time and cost. Construction and Manufacturing industry faces issues in connection with problems related with productivity and the problems are usually connected with performance of employees. The performance of employees is affected by many factors. In this paper a survey was made on respondents who are employed various projects of Saudi Arabia. The researcher developed a theoretical framework from the existing research which was used as a Model to collect and analyze the field data to test the hypothesis. In this research activity three predictors (commitment, job satisfaction and job performance) for determining the change in productivity. The results highlight that commitment and job performance (respectively) are the two predictors which are explaining 37% of variation in the productivity of the companies. The results also show that Job Satisfaction has no role in the prediction of productivity.

  7. Olive (Olea europaea L.) tree nitrogen status is a key factor for olive oil quality.

    PubMed

    Erel, Ran; Kerem, Zohar; Ben-Gal, Alon; Dag, Arnon; Schwartz, Amnon; Zipori, Isaac; Basheer, Loai; Yermiyahu, Uri

    2013-11-27

    The influence of macronutrient status on olive oil properties was studied for three years. Data were analyzed by a multivariate model considering N, P, K, and fruiting year as explanatory factors. Oil quality parameters were primarily associated with N concentration in leaves and fruits which increased with N in irrigation solution. The effect of P on oil quality was mainly indirect since increased P availability increased N accumulation. The potassium level had negligible effects. The oil phenolic content decreased linearly as a function of increased leaf N, indicating protein-phenol competition in leaves. The overall saturation level of the fatty acids decreased with fruit N, resulting in increased polyunsaturated fatty acids. Free fatty acids increased with increased levels of fruit N. High fruit load tended to reduce fruit N and subsequently improve oil quality. The effect of N on oil properties depended solely on its concentration in leaves or fruits, regardless of the cause. PMID:24245487

  8. A Key Role for Leukemia Inhibitory Factor in C26 Cancer Cachexia.

    PubMed

    Seto, Danielle N; Kandarian, Susan C; Jackman, Robert W

    2015-08-01

    Cachexia is an exacerbating event in many types of cancer that is strongly associated with a poor prognosis. We have identified cytokine, signaling, and transcription factors that are required for cachexia in the mouse C26 colon carcinoma model of cancer. C2C12 myotubes treated with conditioned medium from C26 cancer cells induced atrophy and activated a STAT-dependent reporter gene but not reporter genes dependent on SMAD, FOXO, C/EBP, NF-κB, or AP-1. Of the gp130 family members IL-11, IL-6, oncostatin M (OSM), and leukemia inhibitory factor (LIF), only OSM and LIF were sufficient to activate the STAT reporter in myotubes. LIF was elevated in C26 conditioned medium (CM), but IL-6, OSM, TNFα, and myostatin were not. A LIF-blocking antibody abolished C26 CM-induced STAT reporter activation, STAT3 phosphorylation, and myotube atrophy but blocking antibodies to IL-6 or OSM did not. JAK2 inhibitors also blocked C26 CM-induced STAT reporter activation, STAT3 phosphorylation, and atrophy in myotubes. LIF at levels found in the C26 CM was sufficient for STAT reporter activation and atrophy in myotubes. In vivo, an increase in serum LIF preceded the increase in IL-6 in mice with C26 tumors. Overexpression of a dominant negative Stat3Cβ-EGFP gene in myotubes and in mouse muscle blocked the atrophy caused by C26 CM or C26 tumors, respectively. Taken together, these data support an important role of LIF-JAK2-STAT3 in C26 cachexia and point to a therapeutic approach for at least some types of cancer cachexia. PMID:26092726

  9. Identification of Transcriptional Factors and Key Genes in Primary Osteoporosis by DNA Microarray

    PubMed Central

    Xie, Wengui; Ji, Lixin; Zhao, Teng; Gao, Pengfei

    2015-01-01

    Background A number of genes have been identified to be related with primary osteoporosis while less is known about the comprehensive interactions between regulating genes and proteins. We aimed to identify the differentially expressed genes (DEGs) and regulatory effects of transcription factors (TFs) involved in primary osteoporosis. Material/Methods The gene expression profile GSE35958 was obtained from Gene Expression Omnibus database, including 5 primary osteoporosis and 4 normal bone tissues. The differentially expressed genes between primary osteoporosis and normal bone tissues were identified by the same package in R language. The TFs of these DEGs were predicted with the Essaghir A method. DAVID (The Database for Annotation, Visualization and Integrated Discovery) was applied to perform the GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway enrichment analysis of DEGs. After analyzing regulatory effects, a regulatory network was built between TFs and the related DEGs. Results A total of 579 DEGs was screened, including 310 up-regulated genes and 269 down-regulated genes in primary osteoporosis samples. In GO terms, more up-regulated genes were enriched in transcription regulator activity, and secondly in transcription factor activity. A total 10 significant pathways were enriched in KEGG analysis, including colorectal cancer, Wnt signaling pathway, Focal adhesion, and MAPK signaling pathway. Moreover, total 7 TFs were enriched, of which CTNNB1, SP1, and TP53 regulated most up-regulated DEGs. Conclusions The discovery of the enriched TFs might contribute to the understanding of the mechanism of primary osteoporosis. Further research on genes and TFs related to the WNT signaling pathway and MAPK pathway is urgent for clinical diagnosis and directing treatment of primary osteoporosis. PMID:25957414

  10. Security analysis and improvements of two-factor mutual authentication with key agreement in wireless sensor networks.

    PubMed

    Kim, Jiye; Lee, Donghoon; Jeon, Woongryul; Lee, Youngsook; Won, Dongho

    2014-01-01

    User authentication and key management are two important security issues in WSNs (Wireless Sensor Networks). In WSNs, for some applications, the user needs to obtain real-time data directly from sensors and several user authentication schemes have been recently proposed for this case. We found that a two-factor mutual authentication scheme with key agreement in WSNs is vulnerable to gateway node bypassing attacks and user impersonation attacks using secret data stored in sensor nodes or an attacker's own smart card. In this paper, we propose an improved scheme to overcome these security weaknesses by storing secret data in unique ciphertext form in each node. In addition, our proposed scheme should provide not only security, but also efficiency since sensors in a WSN operate with resource constraints such as limited power, computation, and storage space. Therefore, we also analyze the performance of the proposed scheme by comparing its computation and communication costs with those of other schemes. PMID:24721764

  11. Security Analysis and Improvements of Two-Factor Mutual Authentication with Key Agreement in Wireless Sensor Networks

    PubMed Central

    Kim, Jiye; Lee, Donghoon; Jeon, Woongryul; Lee, Youngsook; Won, Dongho

    2014-01-01

    User authentication and key management are two important security issues in WSNs (Wireless Sensor Networks). In WSNs, for some applications, the user needs to obtain real-time data directly from sensors and several user authentication schemes have been recently proposed for this case. We found that a two-factor mutual authentication scheme with key agreement in WSNs is vulnerable to gateway node bypassing attacks and user impersonation attacks using secret data stored in sensor nodes or an attacker's own smart card. In this paper, we propose an improved scheme to overcome these security weaknesses by storing secret data in unique ciphertext form in each node. In addition, our proposed scheme should provide not only security, but also efficiency since sensors in a WSN operate with resource constraints such as limited power, computation, and storage space. Therefore, we also analyze the performance of the proposed scheme by comparing its computation and communication costs with those of other schemes. PMID:24721764

  12. Controlled quantum key distribution with three-photon polarization-entangled states via the collective noise channel

    SciTech Connect

    Dong Li; Xiu Xiaoming; Gao Yajun; Yi, X. X.

    2011-10-15

    Using three-photon polarization-entangled GHZ states or W states, we propose controlled quantum key distribution protocols for circumventing two main types of collective noise, collective dephasing noise, or collective rotation noise. Irrespective of the number of controllers, a three-photon state can generate a one-bit secret key. The storage technique of quantum states is dispensable for the controller and the receiver, and it therefore allows performing the process in a more convenient mode. If the photon cost in a security check is disregarded, then the efficiency theoretically approaches unity.

  13. Factor Structure of Locus of Control in Children

    ERIC Educational Resources Information Center

    Nowicki, Stephen

    1976-01-01

    The present study attempted to identify the factor structure of the Children's Nowicki-Strickland Internal-External Control Scale by factor-analysis of the responses of 388 junior high, 389 high school and 449 elementary school students. (MS)

  14. Platelet-Derived Growth Factor: A Key Factor in the Pathogenesis of Graves' Ophthalmopathy and Potential Target for Treatment

    PubMed Central

    Virakul, Sita; van Steensel, Leendert; Dalm, Virgil A.S.H.; Paridaens, Dion; van Hagen, P. Martin; Dik, Willem A.

    2014-01-01

    Activation of orbital fibroblasts resulting in excessive proliferation, cytokine and hyaluronan production and differentiation into adipocytes, is a main determinant of orbital tissue inflammation and tissue expansion in Graves' ophthalmopathy (GO). During the last years we have shown that the platelet-derived growth factor (PDGF) isoforms PDGF-AA, PDGF-AB and PDGF-BB are increased in orbital tissue from GO patients with active and inactive disease. These PDGF isoforms exhibit the capacity to stimulate proliferation, hyaluronan and cytokine/chemokine production by orbital fibroblasts. Moreover, PDGF-AB and PDGF-BB increase thyroid stimulating hormone receptor (TSHR) expression by orbital fibroblasts, which enhances the orbital fibroblast activating capacity of the THSR stimulatory autoantibodies present in Graves' disease (GD) patients. Of these PDGF isoforms PDGF-BB exhibits the strongest orbital fibroblast activating effects, which is likely related to its ability to bind both the PDGF-receptor (PDGF-R)α and PDGF-Rβ chains. Thus the PDGF-system fulfills important roles in orbital fibroblast activation in both active and inactive GO, which supports a therapeutic rationale for blocking PDGF signaling in GO. Tyrosine kinase inhibitors (TKIs) may be candidates to target PDGF signaling. Of several TKIs tested dasatinib exhibited the highest potency to block PDGF-R signaling in orbital fibroblasts and may represent a promising compound for the treatment of GO as it was effective at low dosage and is associated with less side effects compared to imatinib mesylate and nilotinib. In this review the contribution of PDGF to the pathophysiology of GO as well as therapeutic approaches to target this PDGF-system will be addressed. PMID:25759797

  15. Key Residential Building Equipment Technologies for Control and Grid Support PART I (Residential)

    SciTech Connect

    Starke, Michael R; Onar, Omer C; DeVault, Robert C

    2011-09-01

    based on the largest electrical energy consumers in the residential sector are space heating and cooling, washer and dryer, water heating, lighting, computers and electronics, dishwasher and range, and refrigeration. As the largest loads, these loads provide the highest potential for delivering demand response and reliability services. Many residential loads have inherent flexibility that is related to the purpose of the load. Depending on the load type, electric power consumption levels can either be ramped, changed in a step-change fashion, or completely removed. Loads with only on-off capability (such as clothes washers and dryers) provide less flexibility than resources that can be ramped or step-changed. Add-on devices may be able to provide extra demand response capabilities. Still, operating residential loads effectively requires awareness of the delicate balance of occupants health and comfort and electrical energy consumption. This report is Phase I of a series of reports aimed at identifying gaps in automated home energy management systems for incorporation of building appliances, vehicles, and renewable adoption into a smart grid, specifically with the intent of examining demand response and load factor control for power system support. The objective is to capture existing gaps in load control, energy management systems, and sensor technology with consideration of PHEV and renewable technologies to establish areas of research for the Department of Energy. In this report, (1) data is collected and examined from state of the art homes to characterize the primary residential loads as well as PHEVs and photovoltaic for potential adoption into energy management control strategies; and (2) demand response rules and requirements across the various demand response programs are examined for potential participation of residential loads. This report will be followed by a Phase II report aimed at identifying the current state of technology of energy management systems

  16. Zinc regulates a key transcriptional pathway for epileptogenesis via metal-regulatory transcription factor 1.

    PubMed

    van Loo, Karen M J; Schaub, Christina; Pitsch, Julika; Kulbida, Rebecca; Opitz, Thoralf; Ekstein, Dana; Dalal, Adam; Urbach, Horst; Beck, Heinz; Yaari, Yoel; Schoch, Susanne; Becker, Albert J

    2015-01-01

    Temporal lobe epilepsy (TLE) is the most common focal seizure disorder in adults. In many patients, transient brain insults, including status epilepticus (SE), are followed by a latent period of epileptogenesis, preceding the emergence of clinical seizures. In experimental animals, transcriptional upregulation of CaV3.2 T-type Ca(2+)-channels, resulting in an increased propensity for burst discharges of hippocampal neurons, is an important trigger for epileptogenesis. Here we provide evidence that the metal-regulatory transcription factor 1 (MTF1) mediates the increase of CaV3.2 mRNA and intrinsic excitability consequent to a rise in intracellular Zn(2+) that is associated with SE. Adeno-associated viral (rAAV) transfer of MTF1 into murine hippocampi leads to increased CaV3.2 mRNA. Conversely, rAAV-mediated expression of a dominant-negative MTF1 abolishes SE-induced CaV3.2 mRNA upregulation and attenuates epileptogenesis. Finally, data from resected human hippocampi surgically treated for pharmacoresistant TLE support the Zn(2+)-MTF1-CaV3.2 cascade, thus providing new vistas for preventing and treating TLE. PMID:26498180

  17. Zinc regulates a key transcriptional pathway for epileptogenesis via metal-regulatory transcription factor 1

    PubMed Central

    van Loo, Karen M. J.; Schaub, Christina; Pitsch, Julika; Kulbida, Rebecca; Opitz, Thoralf; Ekstein, Dana; Dalal, Adam; Urbach, Horst; Beck, Heinz; Yaari, Yoel; Schoch, Susanne; Becker, Albert J.

    2015-01-01

    Temporal lobe epilepsy (TLE) is the most common focal seizure disorder in adults. In many patients, transient brain insults, including status epilepticus (SE), are followed by a latent period of epileptogenesis, preceding the emergence of clinical seizures. In experimental animals, transcriptional upregulation of CaV3.2 T-type Ca2+-channels, resulting in an increased propensity for burst discharges of hippocampal neurons, is an important trigger for epileptogenesis. Here we provide evidence that the metal-regulatory transcription factor 1 (MTF1) mediates the increase of CaV3.2 mRNA and intrinsic excitability consequent to a rise in intracellular Zn2+ that is associated with SE. Adeno-associated viral (rAAV) transfer of MTF1 into murine hippocampi leads to increased CaV3.2 mRNA. Conversely, rAAV-mediated expression of a dominant-negative MTF1 abolishes SE-induced CaV3.2 mRNA upregulation and attenuates epileptogenesis. Finally, data from resected human hippocampi surgically treated for pharmacoresistant TLE support the Zn2+-MTF1-CaV3.2 cascade, thus providing new vistas for preventing and treating TLE. PMID:26498180

  18. Protein Adsorption Patterns and Analysis on IV Nanoemulsions—The Key Factor Determining the Organ Distribution

    PubMed Central

    Keck, Cornelia M.; Jansch, Mirko; Müller, Rainer H.

    2012-01-01

    Intravenous nanoemulsions have been on the market for parenteral nutrition since the 1950s; meanwhile, they have also been used successfully for IV drug delivery. To be well tolerable, the emulsions should avoid uptake by the MPS cells of the body; for drug delivery, they should be target-specific. The organ distribution is determined by the proteins adsorbing them after injection from the blood (protein adsorption pattern), typically analyzed by two-dimensional polyacrylamide gel electrophoresis, 2-D PAGE. The article reviews the 2-D PAGE method, the analytical problems to be faced and the knowledge available on how the composition of emulsions affects the protein adsorption patterns, e.g., the composition of the oil phase, stabilizer layer and drug incorporation into the interface or oil core. Data were re-evaluated and compared, and the implications for the in vivo distribution are discussed. Major results are that the interfacial composition of the stabilizer layer is the main determining factor and that this composition can be modulated by simple processes. Drug incorporation affects the pattern depending on the localization of the drug (oil core versus interface). The data situation regarding in vivo effects is very limited; mainly, it has to be referred to in the in vivo data of polymeric nanoparticles. As a conclusion, determination of the protein adsorption patterns can accelerate IV nanoemulsion formulation development regarding optimized organ distribution and related pharmacokinetics. PMID:24300396

  19. Key factors in work engagement and job motivation of teaching faculty at a university medical centre.

    PubMed

    van den Berg, B A M; Bakker, Arnold B; Ten Cate, Th J

    2013-11-01

    This study reports about teacher motivation and work engagement in a Dutch University Medical Centre (UMC). We examined factors affecting the motivation for teaching in a UMC, the engagement of UMC Utrecht teaching faculty in their work, and their engagement in teaching compared with engagement in patient care and research. Based on a pilot study within various departments at the UMCU, a survey on teaching motivation and work engagement was developed and sent to over 600 UMCU teachers. About 50 % responded. Work engagement was measured by the Utrecht Work Engagement Scale, included in this survey. From a list of 22 pre-defined items, 5 were marked as most motivating: teaching about my own speciality, noticeable appreciation for teaching by my direct superior, teaching small groups, feedback on my teaching performance, and freedom to determine what I teach. Feedback on my teaching performance showed the strongest predictive value for teaching engagement. Engagement scores were relatively favourable, but engagement with patient care was higher than with research and teaching. Task combinations appear to decrease teaching engagement. Our results match with self-determination theory and the job demands-resources model, and challenge the policy to combine teaching with research and patient care. PMID:24037742

  20. Research on key factors in the digital shearing speckle pattern interferometry

    NASA Astrophysics Data System (ADS)

    Feng, Ziang; Gao, Zhan; Zhang, Xiaoqiong; Wang, Shengjia

    2015-08-01

    Digital shearing speckle pattern interferometry (DSSPI) is a powerful tool in the measurement of strain, residual stress and the non-destructive testing (NDT). It is widely used in the fields of wood testing, tire inspection and aerospace, etc. The DSSPI system based on the Wollaston prism is attractive because of its compact arrangement, high immunity to disturbance, and, most of all, the ability to measure strain directly. It could show the strain distribution of the measured object by producing fringe patterns. In conventional DSSPI systems, phase-shifting devices are commonly adopted to extract phase information from the fringe patterns, which means dynamical measurement cannot be realized. In this paper, the principle of a novel DSSPI system based on the temporal analysis is presented. Phase information is extracted with the Fourier Transform method instead of the phase-shifting devices in this system. In this way, dynamical measurement is realized. The measuring accuracy is mostly determined by the quality of the fringe patterns (the fringe width and the contrast ratio). There are several factors that influence the quality of the fringe patterns. Here we mainly discuss the influence of the shearing distance and the polarization state. The preliminary experiments with different shearing distances and polarization states are conducted. The ideal shearing distance and polarization state are suggested.

  1. Physiologically-based toxicokinetic models help identifying the key factors affecting contaminant uptake during flood events.

    PubMed

    Brinkmann, Markus; Eichbaum, Kathrin; Kammann, Ulrike; Hudjetz, Sebastian; Cofalla, Catrina; Buchinger, Sebastian; Reifferscheid, Georg; Schüttrumpf, Holger; Preuss, Thomas; Hollert, Henner

    2014-07-01

    As a consequence of global climate change, we will be likely facing an increasing frequency and intensity of flood events. Thus, the ecotoxicological relevance of sediment re-suspension is of growing concern. It is vital to understand contaminant uptake from suspended sediments and relate it to effects in aquatic biota. Here we report on a computational study that utilizes a physiologically based toxicokinetic model to predict uptake, metabolism and excretion of sediment-borne pyrene in rainbow trout (Oncorhynchus mykiss). To this end, data from two experimental studies were compared with the model predictions: (a) batch re-suspension experiments with constant concentration of suspended particulate matter at two different temperatures (12 and 24°C), and (b) simulated flood events in an annular flume. The model predicted both the final concentrations and the kinetics of 1-hydroxypyrene secretion into the gall bladder of exposed rainbow trout well. We were able to show that exhaustive exercise during exposure in simulated flood events can lead to increased levels of biliary metabolites and identified cardiac output and effective respiratory volume as the two most important factors for contaminant uptake. The results of our study clearly demonstrate the relevance and the necessity to investigate uptake of contaminants from suspended sediments under realistic exposure scenarios. PMID:24727214

  2. Key geochemical factors regulating Mn(IV)-catalyzed anaerobic nitrification in coastal marine sediments

    NASA Astrophysics Data System (ADS)

    Lin, Hui; Taillefert, Martial

    2014-05-01

    The reduction of Mn(IV) oxides coupled to the anaerobic oxidation of NH4+ has been proposed for more than a decade to contribute to the fixed nitrogen pool in marine sediments, yet the existence of this process is still under debate. In this study, surface sediments from an intertidal salt marsh were incubated with MnO2 in the presence of elevated concentrations of NH4+ to test the hypothesis that the reduction of Mn(IV) oxides catalyzes anaerobic NH4+ oxidation to NO2- or NO3-. Geochemical factors such as the ratio of Mn(IV) to NH4+, the type of Mn(IV) oxides (amorphous or colloidal MnO2), and the redox potential of the sediment significantly affect the activity of anaerobic nitrification. Incubations show that the net production of NO3- is stimulated under anaerobic conditions with external addition of colloidal but not amorphous MnO2 and is facilitated by the presence of high concentrations of NH4+. Mass balance calculations demonstrate that anaerobic NH4+ oxidation contributes to the net consumption of NH4+, providing another piece of evidence for the occurrence of Mn(IV)-catalyzed anaerobic nitrification in coastal marine sediments. Finally, anaerobic nitrification is stimulated by the amendment of small concentrations of NO3- or the absence of sulfate reduction, suggesting that moderately reducing conditions favor anaerobic NH4+ oxidation. Overall, these findings suggest that Mn(IV)-catalyzed anaerobic nitrification in suboxic sediments with high N/Mn concentration ratios and highly reactive manganese oxides may be an important source of NO2- and NO3- for subsequent marine nitrogen loss via denitrification or anammox.

  3. Identification of key parameters controlling dissolved oxygen migration and attenuation in fractured crystalline rocks.

    PubMed

    Spiessl, S M; MacQuarrie, K T B; Mayer, K U

    2008-01-28

    In the crystalline rocks of the Canadian Shield, geochemical conditions are currently reducing at depths of 500-1000 m. However, during future glacial periods, altered hydrologic conditions could potentially result in enhanced recharge of glacial melt water containing a relatively high concentration of dissolved oxygen (O2). It is therefore of interest to investigate the physical and geochemical processes, including naturally-occurring redox reactions, that may control O2 ingress. In this study, the reactive transport code MIN3P is used in combination with 2k factorial analyses to identify the most important parameters controlling oxygen migration and attenuation in fractured crystalline rocks. Scenarios considered are based on simplified conceptual models that include a single vertical fracture, or a fracture zone, contained within a rock matrix that extends from the ground surface to a depth of 500 m. Consistent with field observations, Fe(II)-bearing minerals are present in the fractures (i.e. chlorite) and the rock matrix (biotite and small quantities of pyrite). For the parameter ranges investigated, results indicate that for the single fracture case, the most influential factors controlling dissolved O2 ingress are flow velocity in the fracture, fracture aperture, and the biotite reaction rate in the rock matrix. The most important parameters for the fracture zone simulations are flow velocity in the individual fractures, pO2 in the recharge water, biotite reaction rate, and to a lesser degree the abundance and reactivity of chlorite in the fracture zone, and the fracture zone width. These parameters should therefore receive increased consideration during site characterization, and in the formulation of site-specific models intended to predict O2 behavior in crystalline rocks. PMID:17935829

  4. Control circuit maintains unity power factor of reactive load

    NASA Technical Reports Server (NTRS)

    Kramer, M.; Martinage, L. H.

    1966-01-01

    Circuit including feedback control elements automatically corrects the power factor of a reactive load. It maintains power supply efficiency where negative load reactance changes and varies by providing corrective error signals to the control windings of a power supply transformer.

  5. The time of day differently influences fatigue and locomotor activity: is body temperature a key factor?

    PubMed

    Machado, Frederico Sander Mansur; Rodovalho, Gisele Vieira; Coimbra, Cândido Celso

    2015-03-01

    The aim of this study was to verify the possible interactions between exercise capacity and spontaneous locomotor activity (SLA) during the oscillation of core body temperature (Tb) that occurs during the light/dark cycle. Wistar rats (n=11) were kept at an animal facility under a light/dark cycle of 14/10h at an ambient temperature of 23°C and water and food ad libitum. Initially, in order to characterize the daily oscillation in SLA and Tb of the rats, these parameters were continuously recorded for 24h using an implantable telemetric sensor (G2 E-Mitter). The animals were randomly assigned to two progressive exercise test protocols until fatigue during the beginning of light and dark-phases. Fatigue was defined as the moment rats could not keep pace with the treadmill. We assessed the time to fatigue, workload and Tb changes induced by exercise. Each test was separated by 3days. Our results showed that exercise capacity and heat storage were higher during the light-phase (p<0.05). In contrast, we observed that both SLA and Tb were higher during the dark-phase (p<0.01). Notably, the correlation analysis between the amount of SLA and the running capacity observed at each phase of the daily cycle revealed that, regardless of the time of the day, both types of locomotor physical activity have an important inherent component (r=0.864 and r=0.784, respectively, p<0.01) without a direct relationship between them. This finding provides further support for the existence of specific control mechanisms for each type of physical activity. In conclusion, our data indicate that the relationship between the body temperature and different types of physical activity might be affected by the light/dark cycle. These results mean that, although exercise performance and spontaneous locomotor activity are not directly associated, both are strongly influenced by daily cycles of light and dark. PMID:25479573

  6. Factors Controlling Foundation Spending in Vermont.

    ERIC Educational Resources Information Center

    Gratiot, J. Peter

    2000-01-01

    Evidence derived from data accumulated under Vermont's Foundation Plan demonstrates that school district property value is a secondary determinant of school spending level, compared with other factors: the nonresident portion of the property-tax base, resident income, and residents' perceived school-tax burden as a percent of income. (Contains 13…

  7. Soft-Starting Power-Factor Motor Controller

    NASA Technical Reports Server (NTRS)

    Nola, F. J.

    1983-01-01

    Three-phase power-factor controller with soft start is based on earlier version that does not control starting transients. Additional components serve to turn off "run" command signal and substitute gradual startup command signal during preset startup interval. Improved controller reduces large current surge that usually accompanies starting. Controller applies power smoothly, without causing motor vibrations.

  8. Transcription Factor ATAF1 in Arabidopsis Promotes Senescence by Direct Regulation of Key Chloroplast Maintenance and Senescence Transcriptional Cascades.

    PubMed

    Garapati, Prashanth; Xue, Gang-Ping; Munné-Bosch, Sergi; Balazadeh, Salma

    2015-07-01

    Senescence represents a fundamental process of late leaf development. Transcription factors (TFs) play an important role for expression reprogramming during senescence; however, the gene regulatory networks through which they exert their functions, and their physiological integration, are still largely unknown. Here, we identify the Arabidopsis (Arabidopsis thaliana) abscisic acid (ABA)- and hydrogen peroxide-activated TF Arabidopsis thaliana activating factor1 (ATAF1) as a novel upstream regulator of senescence. ATAF1 executes its physiological role by affecting both key chloroplast maintenance and senescence-promoting TFs, namely GOLDEN2-LIKE1 (GLK1) and ORESARA1 (Arabidopsis NAC092), respectively. Notably, while ATAF1 activates ORESARA1, it represses GLK1 expression by directly binding to their promoters, thereby generating a transcriptional output that shifts the physiological balance toward the progression of senescence. We furthermore demonstrate a key role of ATAF1 for ABA- and hydrogen peroxide-induced senescence, in accordance with a direct regulatory effect on ABA homeostasis genes, including nine-CIS-epoxycarotenoid dioxygenase3 involved in ABA biosynthesis and ABC transporter G family member40, encoding an ABA transport protein. Thus, ATAF1 serves as a core transcriptional activator of senescence by coupling stress-related signaling with photosynthesis- and senescence-related transcriptional cascades. PMID:25953103

  9. HUMAN FACTORS GUIDANCE FOR CONTROL ROOM EVALUATION

    SciTech Connect

    OHARA,J.; BROWN,W.; STUBLER,W.; HIGGINS,J.; WACHTEL,J.; PERSENSKY,J.J.

    2000-07-30

    The Human-System Interface Design Review Guideline (NUREG-0700, Revision 1) was developed by the US Nuclear Regulatory Commission (NRC) to provide human factors guidance as a basis for the review of advanced human-system interface technologies. The guidance consists of three components: design review procedures, human factors engineering guidelines, and a software application to provide design review support called the ``Design Review Guideline.'' Since it was published in June 1996, Rev. 1 to NUREG-0700 has been used successfully by NRC staff, contractors and nuclear industry organizations, as well as by interested organizations outside the nuclear industry. The NRC has committed to the periodic update and improvement of the guidance to ensure that it remains a state-of-the-art design evaluation tool in the face of emerging and rapidly changing technology. This paper addresses the current research to update of NUREG-0700 based on the substantial work that has taken place since the publication of Revision 1.

  10. LABORATORY AND COMPUTATIONAL INVESTIGATIONS OF THE ATMOSPHERIC CHEMISTRY OF KEY OXIDATION PRODUCTS CONTROLLING TROPOSPHERIC OZONE FORMATION

    EPA Science Inventory

    Major uncertainties remain in our ability to identify the key reactions and primary oxidation products of volatile hydrocarbons that contribute to ozone formation in the troposphere. To reduce these uncertainties, computational chemistry, mechanistic and process analysis techniqu...

  11. Response Regulator Heterodimer Formation Controls a Key Stage in Streptomyces Development

    PubMed Central

    Al-Bassam, Mahmoud M.; Bibb, Maureen J.; Bush, Matthew J.; Chandra, Govind; Buttner, Mark J.

    2014-01-01

    The orphan, atypical response regulators BldM and WhiI each play critical roles in Streptomyces differentiation. BldM is required for the formation of aerial hyphae, and WhiI is required for the differentiation of these reproductive structures into mature spores. To gain insight into BldM function, we defined the genome-wide BldM regulon using ChIP-Seq and transcriptional profiling. BldM target genes clustered into two groups based on their whi gene dependency. Expression of Group I genes depended on bldM but was independent of all the whi genes, and biochemical experiments showed that Group I promoters were controlled by a BldM homodimer. In contrast, Group II genes were expressed later than Group I genes and their expression depended not only on bldM but also on whiI and whiG (encoding the sigma factor that activates whiI). Additional ChIP-Seq analysis showed that BldM Group II genes were also direct targets of WhiI and that in vivo binding of WhiI to these promoters depended on BldM and vice versa. We go on to demonstrate that BldM and WhiI form a functional heterodimer that controls Group II promoters, serving to integrate signals from two distinct developmental pathways. The BldM-WhiI system thus exemplifies the potential of response regulator heterodimer formation as a mechanism to expand the signaling capabilities of bacterial cells. PMID:25101778

  12. Proportional-Integral-Derivative (PID) Control of Secreted Factors for Blood Stem Cell Culture

    PubMed Central

    Caldwell, Julia; Wang, Weijia; Zandstra, Peter W.

    2015-01-01

    Clinical use of umbilical cord blood has typically been limited by the need to expand hematopoietic stem and progenitor cells (HSPC) ex vivo. This expansion is challenging due to the accumulation of secreted signaling factors in the culture that have a negative regulatory effect on HSPC output. Strategies for global regulation of these factors through dilution have been developed, but do not accommodate the dynamic nature or inherent variability of hematopoietic cell culture. We have developed a mathematical model to simulate the impact of feedback control on in vitro hematopoiesis, and used it to design a proportional-integral-derivative (PID) control algorithm. This algorithm was implemented with a fed-batch bioreactor to regulate the concentrations of secreted factors. Controlling the concentration of a key target factor, TGF-β1, through dilution limited the negative effect it had on HSPCs, and allowed global control of other similarly-produced inhibitory endogenous factors. The PID control algorithm effectively maintained the target soluble factor at the target concentration. We show that feedback controlled dilution is predicted to be a more cost effective dilution strategy compared to other open-loop strategies, and can enhance HSPC expansion in short term culture. This study demonstrates the utility of secreted factor process control strategies to optimize stem cell culture systems, and motivates the development of multi-analyte protein sensors to automate the manufacturing of cell therapies. PMID:26348930

  13. Cortistatin Is a Key Factor Regulating the Sex-Dependent Response of the GH and Stress Axes to Fasting in Mice.

    PubMed

    Cordoba-Chacón, José; Gahete, Manuel D; Pozo-Salas, Ana I; de Lecea, Luis; Castaño, Justo P; Luque, Raúl M

    2016-07-01

    Cortistatin (CORT) shares high structural and functional similarities with somatostatin (SST) but displays unique sex-dependent pituitary actions. Indeed, although female CORT-knockout (CORT-KO) mice exhibit enhanced GH expression/secretion, Proopiomelanocortin expression, and circulating ACTH/corticosterone/ghrelin levels, male CORT-KO mice only display increased plasma GH/corticosterone levels. Changes in peripheral ghrelin and SST (rather than hypothalamic levels) seem to regulate GH/ACTH axes in CORT-KOs under fed conditions. Because changes in GH/ACTH axes during fasting provide important adaptive mechanisms, we sought to determine whether CORT absence influences GH/ACTH axes during fasting. Accordingly, fed and fasted male/female CORT-KO were compared with littermate controls. Fasting increased circulating GH levels in male/female controls but not in CORT-KO, suggesting that CORT can be a relevant regulator of GH secretion during fasting. However, GH levels were already higher in CORT-KO than in controls in fed state, which might preclude a further elevation in GH levels. Interestingly, although fasting-induced pituitary GH expression was elevated in both male/female controls, GH expression only increased in fasted female CORT-KOs, likely owing to specific changes observed in key factors controlling somatotrope responsiveness (ie, circulating ghrelin and IGF-1, and pituitary GHRH and ghrelin receptor expression). Fasting increased corticosterone levels in control and, most prominently, in CORT-KO mice, which might be associated with a desensitization to SST signaling and to an augmentation in CRH and ghrelin-signaling regulating corticotrope function. Altogether, these results provide compelling evidence that CORT plays a key, sex-dependent role in the regulation of the GH/ACTH axes in response to fasting. PMID:27175972

  14. Automatic generation of predictive dynamic models reveals nuclear phosphorylation as the key Msn2 control mechanism.

    PubMed

    Sunnåker, Mikael; Zamora-Sillero, Elias; Dechant, Reinhard; Ludwig, Christina; Busetto, Alberto Giovanni; Wagner, Andreas; Stelling, Joerg

    2013-05-28

    Predictive dynamical models are critical for the analysis of complex biological systems. However, methods to systematically develop and discriminate among systems biology models are still lacking. We describe a computational method that incorporates all hypothetical mechanisms about the architecture of a biological system into a single model and automatically generates a set of simpler models compatible with observational data. As a proof of principle, we analyzed the dynamic control of the transcription factor Msn2 in Saccharomyces cerevisiae, specifically the short-term mechanisms mediating the cells' recovery after release from starvation stress. Our method determined that 12 of 192 possible models were compatible with available Msn2 localization data. Iterations between model predictions and rationally designed phosphoproteomics and imaging experiments identified a single-circuit topology with a relative probability of 99% among the 192 models. Model analysis revealed that the coupling of dynamic phenomena in Msn2 phosphorylation and transport could lead to efficient stress response signaling by establishing a rate-of-change sensor. Similar principles could apply to mammalian stress response pathways. Systematic construction of dynamic models may yield detailed insight into nonobvious molecular mechanisms. PMID:23716718

  15. What factors control superficial lava dome explosivity?

    PubMed Central

    Boudon, Georges; Balcone-Boissard, Hélène; Villemant, Benoît; Morgan, Daniel J.

    2015-01-01

    Dome-forming eruption is a frequent eruptive style and a major hazard on numerous volcanoes worldwide. Lava domes are built by slow extrusion of degassed, viscous magma and may be destroyed by gravitational collapse or explosion. The triggering of lava dome explosions is poorly understood: here we propose a new model of superficial lava-dome explosivity based upon a textural and geochemical study (vesicularity, microcrystallinity, cristobalite distribution, residual water contents, crystal transit times) of clasts produced by key eruptions. Superficial explosion of a growing lava dome may be promoted through porosity reduction caused by both vesicle flattening due to gas escape and syn-eruptive cristobalite precipitation. Both processes generate an impermeable and rigid carapace allowing overpressurisation of the inner parts of the lava dome by the rapid input of vesiculated magma batches. The relative thickness of the cristobalite-rich carapace is an inverse function of the external lava dome surface area. Explosive activity is thus more likely to occur at the onset of lava dome extrusion, in agreement with observations, as the likelihood of superficial lava dome explosions depends inversely on lava dome volume. This new result is of interest for the whole volcanological community and for risk management. PMID:26420069

  16. What factors control superficial lava dome explosivity?

    NASA Astrophysics Data System (ADS)

    Boudon, Georges; Balcone-Boissard, Hélène; Villemant, Benoît; Morgan, Daniel J.

    2015-09-01

    Dome-forming eruption is a frequent eruptive style and a major hazard on numerous volcanoes worldwide. Lava domes are built by slow extrusion of degassed, viscous magma and may be destroyed by gravitational collapse or explosion. The triggering of lava dome explosions is poorly understood: here we propose a new model of superficial lava-dome explosivity based upon a textural and geochemical study (vesicularity, microcrystallinity, cristobalite distribution, residual water contents, crystal transit times) of clasts produced by key eruptions. Superficial explosion of a growing lava dome may be promoted through porosity reduction caused by both vesicle flattening due to gas escape and syn-eruptive cristobalite precipitation. Both processes generate an impermeable and rigid carapace allowing overpressurisation of the inner parts of the lava dome by the rapid input of vesiculated magma batches. The relative thickness of the cristobalite-rich carapace is an inverse function of the external lava dome surface area. Explosive activity is thus more likely to occur at the onset of lava dome extrusion, in agreement with observations, as the likelihood of superficial lava dome explosions depends inversely on lava dome volume. This new result is of interest for the whole volcanological community and for risk management.

  17. Motor power factor controller with a reduced voltage starter

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (Inventor)

    1981-01-01

    A power factor type motor controller is disclosed in which the conventional power factor constant voltage command signal is replaced during a starting interval with a graduated control voltage. This continuation-impart of a pending patent application (Serial No. 199, 765: Three Phase Factor Controller) provides a means for modifying the operation of the system for a motor start-up interval of 5 to 30 second. Using a ramp generators, an initial ramp-like signal replaces a constant power factor signal supplied by a potentiometer. The ramp-like signal is applied to a 15 terminal where it is summed with an operating power factor signal from phase detectors in order to obtain a control signal for ultimately controlling SCR devices. The SCR devices are turned on at an advancing rate with time responsive to the combination signal described rather than simply a function of a ramp-like signal alone.

  18. Factors controlling cardiac neural crest cell migration

    PubMed Central

    Hutson, Mary R

    2010-01-01

    Cardiac neural crest cells originate as part of the postotic caudal rhombencephalic neural crest stream. Ectomesenchymal cells in this stream migrate to the circumpharyngeal ridge and then into the caudal pharyngeal arches where they condense to form first a sheath and then the smooth muscle tunics of the persisting pharyngeal arch arteries. A subset of the cells continues migrating into the cardiac outflow tract where they will condense to form the aorticopulmonary septum. Cell signaling, extracellular matrix and cell-cell contacts are all critical for the initial migration, pauses, continued migration and condensation of these cells. This Review elucidates what is currently known about these factors. PMID:20890117

  19. Essential surgery: key messages from Disease Control Priorities, 3rd edition.

    PubMed

    Mock, Charles N; Donkor, Peter; Gawande, Atul; Jamison, Dean T; Kruk, Margaret E; Debas, Haile T

    2015-05-30

    The World Bank will publish the nine volumes of Disease Control Priorities, 3rd edition, in 2015-16. Volume 1--Essential Surgery--identifies 44 surgical procedures as essential on the basis that they address substantial needs, are cost effective, and are feasible to implement. This report summarises and critically assesses the volume's five key findings. First, provision of essential surgical procedures would avert about 1·5 million deaths a year, or 6-7% of all avertable deaths in low-income and middle-income countries. Second, essential surgical procedures rank among the most cost effective of all health interventions. The surgical platform of the first-level hospital delivers 28 of the 44 essential procedures, making investment in this platform also highly cost effective. Third, measures to expand access to surgery, such as task sharing, have been shown to be safe and effective while countries make long-term investments in building surgical and anaesthesia workforces. Because emergency procedures constitute 23 of the 28 procedures provided at first-level hospitals, expansion of access requires that such facilities be widely geographically diffused. Fourth, substantial disparities remain in the safety of surgical care, driven by high perioperative mortality rates including anaesthesia-related deaths in low-income and middle-income countries. Feasible measures, such as WHO's Surgical Safety Checklist, have led to improvements in safety and quality. Fifth, the large burden of surgical disorders, cost-effectiveness of essential surgery, and strong public demand for surgical services suggest that universal coverage of essential surgery should be financed early on the path to universal health coverage. We point to estimates that full coverage of the component of universal coverage of essential surgery applicable to first-level hospitals would require just over US$3 billion annually of additional spending and yield a benefit-cost ratio of more than 10:1. It would

  20. Contextual factors multiplex to control multisensory processes.

    PubMed

    Sarmiento, Beatriz R; Matusz, Pawel J; Sanabria, Daniel; Murray, Micah M

    2016-01-01

    This study analyzed high-density event-related potentials (ERPs) within an electrical neuroimaging framework to provide insights regarding the interaction between multisensory processes and stimulus probabilities. Specifically, we identified the spatiotemporal brain mechanisms by which the proportion of temporally congruent and task-irrelevant auditory information influences stimulus processing during a visual duration discrimination task. The spatial position (top/bottom) of the visual stimulus was indicative of how frequently the visual and auditory stimuli would be congruent in their duration (i.e., context of congruence). Stronger influences of irrelevant sound were observed when contexts associated with a high proportion of auditory-visual congruence repeated and also when contexts associated with a low proportion of congruence switched. Context of congruence and context transition resulted in weaker brain responses at 228 to 257 ms poststimulus to conditions giving rise to larger behavioral cross-modal interactions. Importantly, a control oddball task revealed that both congruent and incongruent audiovisual stimuli triggered equivalent non-linear multisensory interactions when congruence was not a relevant dimension. Collectively, these results are well explained by statistical learning, which links a particular context (here: a spatial location) with a certain level of top-down attentional control that further modulates cross-modal interactions based on whether a particular context repeated or changed. The current findings shed new light on the importance of context-based control over multisensory processing, whose influences multiplex across finer and broader time scales. PMID:26466522

  1. Circadian Clock Control of Endocrine Factors

    PubMed Central

    Gamble, Karen L.; Berry, Ryan; Frank, Stuart J.; Young, Martin E.

    2015-01-01

    Organisms experience dramatic fluctuations in demands/stresses over the course of the day. In order to maintain biological processes within physiologic boundaries, it is imperative that mechanisms have evolved for anticipation of, and adaptation to, these daily fluctuations. Endocrine factors undoubtedly play an integral role in homeostasis. Not only do circulating levels of various endocrine factors oscillate over the 24 period, but so too does responsiveness of target tissues to these signals/stimuli. Emerging evidence suggests that these daily oscillations do not occur solely in response to behavioral fluctuations associated with sleep/wake and feeding/fasting cycles, but are orchestrated in part by an intrinsic timekeeping mechanism known as the circadian clock. Disruption of circadian clocks, through genetic and/or environmental means, appears to precipitate numerous common disorders, including cardiometabolic diseases and cancer. Collectively, these observations, which are reviewed within the current article, have led to suggestion that strategies designed to realign normal circadian rhythmicities hold a therapeutic potential for the treatment of various endocrine-related disorders. PMID:24863387

  2. Key drivers controlling stable isotope variations in daily precipitation of Costa Rica: Caribbean Sea versus Eastern Pacific Ocean moisture sources

    NASA Astrophysics Data System (ADS)

    Sánchez-Murillo, R.; Birkel, C.; Welsh, K.; Esquivel-Hernández, G.; Corrales-Salazar, J.; Boll, J.; Brooks, E.; Roupsard, O.; Sáenz-Rosales, O.; Katchan, I.; Arce-Mesén, R.; Soulsby, C.; Araguás-Araguás, L. J.

    2016-01-01

    Costa Rica is located on the Central American Isthmus, which receives moisture inputs directly from the Caribbean Sea and the Eastern Pacific Ocean. This location includes unique mountainous and lowland microclimates, but only limited knowledge exists about the impact of relief and regional atmospheric circulation patterns on precipitation origin, transport, and isotopic composition. Therefore, the main scope of this project is to identify the key drivers controlling stable isotope variations in daily-scale precipitation of Costa Rica. The monitoring sites comprise three strategic locations across Costa Rica: Heredia (Central Valley), Turrialba (Caribbean slope), and Caño Seco (South Pacific slope). Sporadic dry season rain is mostly related to isolated enriched events ranging from -5.8‰ to -0.9‰ δ18O. By mid-May, the Intertropical Convergence Zone reaches Costa Rica resulting in a notable depletion in isotope ratios (up to -18.5‰ δ18O). HYSPLIT air mass back trajectories indicate the strong influence on the origin and transport of precipitation of three main moisture transport mechanisms, the Caribbean Low Level Jet, the Colombian Low Level Jet, and localized convection events. Multiple linear regression models constructed based on Random Forests of surface meteorological information and atmospheric sounding profiles suggest that lifted condensation level and surface relative humidity are the main factors controlling isotopic variations. These findings diverge from the recognized 'amount effect' in monthly composite samples across the tropics. Understanding of stable isotope dynamics in tropical precipitation can be used to a) enhance groundwater modeling efforts in ungauged basins where scarcity of long-term monitoring data drastically limit current and future water resources management, b) improve the re-construction of paleoclimatic records in the Central American land bridge, c) calibrate and validate regional circulation models.

  3. Temperature Dependence of Factors Controlling Isoprene Emissions

    NASA Technical Reports Server (NTRS)

    Duncan, Bryan N.; Yoshida, Yasuko; Damon, Megan R.; Douglass, Anne R.; Witte, Jacquelyn C.

    2009-01-01

    We investigated the relationship of variability in the formaldehyde (HCHO) columns measured by the Aura Ozone Monitoring Instrument (OMI) to isoprene emissions in the southeastern United States for 2005-2007. The data show that the inferred, regional-average isoprene emissions varied by about 22% during summer and are well correlated with temperature, which is known to influence emissions. Part of the correlation with temperature is likely associated with other causal factors that are temperature-dependent. We show that the variations in HCHO are convolved with the temperature dependence of surface ozone, which influences isoprene emissions, and the dependence of the HCHO column to mixed layer height as OMI's sensitivity to HCHO increases with altitude. Furthermore, we show that while there is an association of drought with the variation in HCHO, drought in the southeastern U.S. is convolved with temperature.

  4. Key factors influencing adoption of an innovation in primary health care: a qualitative study based on implementation theory

    PubMed Central

    2010-01-01

    Background Bridging the knowledge-to-practice gap in health care is an important issue that has gained interest in recent years. Implementing new methods, guidelines or tools into routine care, however, is a slow and unpredictable process, and the factors that play a role in the change process are not yet fully understood. There is a number of theories concerned with factors predicting successful implementation in various settings, however, this issue is insufficiently studied in primary health care (PHC). The objective of this article was to apply implementation theory to identify key factors influencing the adoption of an innovation being introduced in PHC in Sweden. Methods A qualitative study was carried out with staff at six PHC units in Sweden where a computer-based test for lifestyle intervention had been implemented. Two different implementation strategies, implicit or explicit, were used. Sixteen focus group interviews and two individual interviews were performed. In the analysis a theoretical framework based on studies of implementation in health service organizations, was applied to identify key factors influencing adoption. Results The theoretical framework proved to be relevant for studies in PHC. Adoption was positively influenced by positive expectations at the unit, perceptions of the innovation being compatible with existing routines and perceived advantages. An explicit implementation strategy and positive opinions on change and innovation were also associated with adoption. Organizational changes and staff shortages coinciding with implementation seemed to be obstacles for the adoption process. Conclusion When implementation theory obtained from studies in other areas was applied in PHC it proved to be relevant for this particular setting. Based on our results, factors to be taken into account in the planning of the implementation of a new tool in PHC should include assessment of staff expectations, assessment of the perceived need for the

  5. CENP-C and CENP-I are key connecting factors for kinetochore and CENP-A assembly

    PubMed Central

    Shono, Nobuaki; Ohzeki, Jun-ichirou; Otake, Koichiro; Martins, Nuno M. C.; Nagase, Takahiro; Kimura, Hiroshi; Larionov, Vladimir; Earnshaw, William C.; Masumoto, Hiroshi

    2015-01-01

    ABSTRACT Although it is generally accepted that chromatin containing the histone H3 variant CENP-A is an epigenetic mark maintaining centromere identity, the pathways leading to the formation and maintenance of centromere chromatin remain unclear. We previously generated human artificial chromosomes (HACs) whose centromeres contain a synthetic alpha-satellite (alphoid) DNA array containing the tetracycline operator (alphoidtetO). We also obtained cell lines bearing the alphoidtetO array at ectopic integration sites on chromosomal arms. Here, we have examined the regulation of CENP-A assembly at centromeres as well as de novo assembly on the ectopic arrays by tethering tetracycline repressor (tetR) fusions of substantial centromeric factors and chromatin modifiers. This analysis revealed four classes of factors that influence CENP-A assembly. Interestingly, many kinetochore structural components induced de novo CENP-A assembly at the ectopic site. We showed that these components work by recruiting CENP-C and subsequently recruiting M18BP1. Furthermore, we found that CENP-I can also recruit M18BP1 and, as a consequence, enhances M18BP1 assembly on centromeres in the downstream of CENP-C. Thus, we suggest that CENP-C and CENP-I are key factors connecting kinetochore to CENP-A assembly. PMID:26527398

  6. CENP-C and CENP-I are key connecting factors for kinetochore and CENP-A assembly.

    PubMed

    Shono, Nobuaki; Ohzeki, Jun-ichirou; Otake, Koichiro; Martins, Nuno M C; Nagase, Takahiro; Kimura, Hiroshi; Larionov, Vladimir; Earnshaw, William C; Masumoto, Hiroshi

    2015-12-15

    Although it is generally accepted that chromatin containing the histone H3 variant CENP-A is an epigenetic mark maintaining centromere identity, the pathways leading to the formation and maintenance of centromere chromatin remain unclear. We previously generated human artificial chromosomes (HACs) whose centromeres contain a synthetic alpha-satellite (alphoid) DNA array containing the tetracycline operator (alphoid(tetO)). We also obtained cell lines bearing the alphoid(tetO) array at ectopic integration sites on chromosomal arms. Here, we have examined the regulation of CENP-A assembly at centromeres as well as de novo assembly on the ectopic arrays by tethering tetracycline repressor (tetR) fusions of substantial centromeric factors and chromatin modifiers. This analysis revealed four classes of factors that influence CENP-A assembly. Interestingly, many kinetochore structural components induced de novo CENP-A assembly at the ectopic site. We showed that these components work by recruiting CENP-C and subsequently recruiting M18BP1. Furthermore, we found that CENP-I can also recruit M18BP1 and, as a consequence, enhances M18BP1 assembly on centromeres in the downstream of CENP-C. Thus, we suggest that CENP-C and CENP-I are key factors connecting kinetochore to CENP-A assembly. PMID:26527398

  7. CR6-interacting factor 1 is a key regulator in Aβ-induced mitochondrial disruption and pathogenesis of Alzheimer's disease

    PubMed Central

    Byun, J; Son, S M; Cha, M-Y; Shong, M; Hwang, Y J; Kim, Y; Ryu, H; Moon, M; Kim, K-S; Mook-Jung, I

    2015-01-01

    Mitochondrial dysfunction, often characterized by massive fission and other morphological abnormalities, is a well-known risk factor for Alzheimer's disease (AD). One causative mechanism underlying AD-associated mitochondrial dysfunction is thought to be amyloid-β (Aβ), yet the pathways between Aβ and mitochondrial dysfunction remain elusive. In this study, we report that CR6-interacting factor 1 (Crif1), a mitochondrial inner membrane protein, is a key player in Aβ-induced mitochondrial dysfunction. Specifically, we found that Crif1 levels were downregulated in the pathological regions of Tg6799 mice brains, wherein overexpressed Aβ undergoes self-aggregation. Downregulation of Crif1 was similarly observed in human AD brains as well as in SH-SY5Y cells treated with Aβ. In addition, knockdown of Crif1, using RNA interference, induced mitochondrial dysfunction with phenotypes similar to those observed in Aβ-treated cells. Conversely, Crif1 overexpression prevented Aβ-induced mitochondrial dysfunction and cell death. Finally, we show that Aβ-induced downregulation of Crif1 is mediated by enhanced reactive oxygen species (ROS) and ROS-dependent sumoylation of the transcription factor specificity protein 1 (Sp1). These results identify the ROS-Sp1-Crif1 pathway to be a new mechanism underlying Aβ-induced mitochondrial dysfunction and suggest that ROS-mediated downregulation of Crif1 is a crucial event in AD pathology. We propose that Crif1 may serve as a novel therapeutic target in the treatment of AD. PMID:25361083

  8. Fast controller for a unity-power-factor PWM rectifier

    SciTech Connect

    Eissa, M.O.; Leeb, S.B.; Verghese, G.C.; Stankovic, A.M.

    1996-01-01

    This paper presents an analog implementation of a fast controller for a unity-power-factor (UPF) PWM rectifier. The best settling times of many popular controllers for this type of converter are on the order of a few line cycles, corresponding to bandwidths under 20 Hz. The fast controller demonstrated in this paper can exercise control action at a rate comparable to the switching frequency rather than the line frequency. In order to accomplish this while maintaining unity power factor during steady-state operation, the fast controller employs a ripple-feedback cancellation scheme.

  9. Intensive risk factor control in stroke prevention

    PubMed Central

    2013-01-01

    Stroke prevention is an urgent priority because of the aging of the population and the steep association of age and risk of stroke. Direct costs of stroke are expected to more than double in the US between 2012 and 2030. By getting everything right, patients can reduce the risk of stroke by 80% or more; however, getting everything right is a tall order. Roughly in order of importance, this requires smoking cessation, maintenance of a healthy weight, a Cretan Mediterranean diet, blood pressure control, lipid-lowering drugs, appropriate use of antiplatelet agents and anticoagulants, and appropriate carotid endarterectomy and stenting. A new approach called “treating arteries instead of targeting risk factors” appears promising but requires validation in randomized trials. PMID:24167723

  10. Control and the Aged: Environmental or Personality Factors.

    ERIC Educational Resources Information Center

    Tiffany, Phyllis G.; Dey, Kay

    Control over self, lifestyle, and environment is a major factor in how one ages. To investigate how age acts as an environmental force in affecting perceptions of control, 45 adults, aged 60-80, from western Kansas were administered the Wechsler Adult Intelligence Scale (WAIS), the Tiffany Experienced Control Scales (ECS), the Minnesota…

  11. Chemical factors that control lignin polymerization.

    PubMed

    Sangha, Amandeep K; Davison, Brian H; Standaert, Robert F; Davis, Mark F; Smith, Jeremy C; Parks, Jerry M

    2014-01-01

    Lignin is a complex, branched polymer that reinforces plant tissue. Understanding the factors that govern lignin structure is of central importance to the development of technologies for converting lignocellulosic biomass into fuels because lignin imparts resistance to chemical, enzymatic, and mechanical deconstruction. Lignin is formed by enzymatic oxidation of phenolic monomers (monolignols) of three main types, guaiacyl (G), syringyl (S), and p-hydroxyphenyl (H) subunits. It is known that increasing the relative abundance of H subunits results in lower molecular weight lignin polymers and hence more easily deconstructed biomass, but it is not known why. Here, we report an analysis of frontier molecular orbitals in mono-, di-, and trilignols, calculated using density functional theory, which points to a requirement of strong p-electron density on the reacting phenolic oxygen atom of the neutral precursor for enzymatic oxidation to occur. This model is consistent with a proton-coupled electron transfer (PCET) mechanism and for the first time explains why H subunits in certain linkages (β-β or β-5) react poorly and tend to "cap" the polymer. In general, β-5 linkages with either a G or H terminus are predicted to inhibit elongation. More broadly, the model correctly accounts for the reactivity of the phenolic groups in a diverse set of dilignols comprising H and G subunits. Thus, we provide a coherent framework for understanding the propensity toward growth or termination of different terminal subunits in lignin. PMID:24341896

  12. Chemical factors that control lignin polymerization

    SciTech Connect

    Sangha, Amandeep K; Davison, Brian H; Standaert, Robert F; Davis, Dr. Mark F.; Smith, Jeremy C; Parks, Jerry M

    2014-01-01

    Lignin is a complex, branched polymer that reinforces plant tissue. Understanding the factors that govern lignin structure is of central importance to the development of technologies for converting lignocellulosic biomass into fuels because lignin imparts resistance to chemical, enzymatic and mechanical deconstruction. Lignin is formed by enzymatic oxidation of phenolic monomers (monolignols) of three main types, guaiacyl (G), syringyl (S) and p- hydroxyphenyl (H). It is known that increasing the relative abundance of H subunits results in lower molecular-weight lignin polymers, and hence more easily deconstructed biomass, but it is not known why. Here, we report an analysis of frontier molecular orbitals in mono-, di- and trilignols, calculated using density functional theory, which points to a requirement of strong p- electron density on the reacting phenolic oxygen atom of the neutral precursor for enzymatic oxidation to occur. This model is consistent with a proton-coupled electron transfer (PCET) mechanism and for the first time explains why H subunits in certain linkages ( - or -5) react poorly and tend to cap the polymer. In general, -5 linkages with either a G or H terminus are predicted to inhibit elongation. More broadly, the model correctly accounts for the reactivity of the phenolic groups in a diverse set of dilignols comprising H and G subunits. Thus, we provide a coherent framework for understanding the propensity toward growth or termination of different terminal subunits in lignin.

  13. Evaluation of soil factors controlling gully erosion

    NASA Astrophysics Data System (ADS)

    Ollobarren, Paul; Giménez, Rafael; Ángel Campo, Miguel; Casalí, Javier

    2015-04-01

    Current models for prediction of (ephemeral) gully erosion rely mainly on topographic factors while soil conditions are almost neglected. However, soil erodibility is essential for analyzing and properly modeling gully erosion. But, despite the wealth of studies to characterize soil vulnerability to gully erosion, a universal approach is still lacking. Moreover, a useful and feasible soil characterization for gully erosion prediction at large scale should be based on simple, quick, repeatable and relatively inexpensive tests to perform. In this work an experimental approach to quantify soil contribution on gully erosion is proposed. From simple methodologies and techniques found in the literature for assessing physical-chemical properties of the soil, a large pool of variables -that presumably underpin gully erosion- were defined. These methodologies includes the use of vane shear apparatus, penetrometers and a mini-rain simulator as well as some current (modified) laboratory tests for assessing soil crustability and erodibility. Thirteen ephemeral gullies developed under different soil condition in agricultural fields of Navarre (Spain) were selected for experiments. Then, the aforementioned variables were calculated for each of the gullies through field and lab experiments. Furthermore, the most relevant variables were detected by means of multivariate analysis and their contribution to gully erosion was finally quantified by using multiple regression analysis. In addition, gully erosion rates of typical agricultural fields are given.

  14. Capturing the wide variety of impaired fracture healing phenotypes in Neurofibromatosis Type 1 with eight key factors: a computational study

    PubMed Central

    Carlier, A.; Brems, H.; Ashbourn, J. M. A.; Nica, I.; Legius, E.; Geris, L.

    2016-01-01

    Congenital pseudarthrosis of the tibia (CPT) is a rare disease which normally presents itself during early childhood by anterolateral bowing of the tibia and spontaneous tibial fractures. Although the exact etiology of CPT is highly debated, 40–80% of CPT patients are carriers of a mutation in the Neurofibromatosis Type 1 (NF1) gene, which can potentially result in an altered phenotype of the skeletal cells and impaired bone healing. In this study we use a computational model of bone regeneration to examine the effect of the Nf1 mutation on bone fracture healing by altering the parameter values of eight key factors which describe the aberrant cellular behaviour of Nf1 haploinsufficient and Nf1 bi-allelically inactivated cells. We show that the computational model is able to predict the formation of a hamartoma as well as a wide variety of CPT phenotypes through different combinations of altered parameter values. A sensitivity analysis by “Design of Experiments” identified the impaired endochondral ossification process and increased infiltration of fibroblastic cells as key contributors to the degree of severity of CPT. Hence, the computational model results have added credibility to the experimental hypothesis of a genetic cause (i.e. Nf1 mutation) for CPT. PMID:26822862

  15. A new player in X identification: the CLAMP protein is a key factor in Drosophila dosage compensation

    PubMed Central

    Soruco, Marcela M. L.

    2016-01-01

    Dosage compensation adjusts the expression levels of genes on one or both targeted sex chromosomes in heterogametic species. This process results in the normalized transcriptional output of important and essential gene families encoded on multiple chromosomes. The mechanisms of dosage compensation have been studied in many model organisms, including Drosophila melanogaster (fly), Caenorhabditis elegans (worm), and Mus musculus (mouse). Although the mechanisms of dosage compensations differ among these species, all of these processes rely on the initial discrimination of the X chromosome from autosomes. Recently, a new paradigm for how the X chromosome is targeted for regulation was identified in Drosophila. This mechanism involves a newly identified zinc finger protein, CLAMP. Here, we review important factors involved in dosage compensation across species with special focus on the fly. Understanding how the newly identified CLAMP protein is involved in X targeting in the fly could provide key insights into how the X chromosome is initially identified across species. PMID:25102930

  16. Sweat, Brain-Power, Horsepower, and Time - The Keys to Controlling Weeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed control in organic crop production is difficult and costly. Early studies on organic weed control in conservation tillage systems were disappointing. Research shifted to organic weed control in conventional tillage systems. Intense cultivation with a tine weeder was the most consistent metho...

  17. The bHLH transcription factor SPATULA is a key regulator of organ size in Arabidopsis thaliana

    PubMed Central

    Makkena, Srilakshmi; Lamb, Rebecca S.

    2013-01-01

    Plant organ size and thus plant size is determined by both cell proliferation and cell expansion. The bHLH transcription factor SPATULA (SPT) was originally identified as a regulator of carpel patterning. It has subsequently been found to control growth of the organs of the shoot. It does this at least in part by controlling the size of meristematic regions of organs in parallel to gibberellic acid (GA). It also acts downstream of several environmental signals, influencing growth in response to light and temperature. We have recently demonstrated that SPT functions to repress the size of the root meristem and thus root growth and size. It appears to do this using a similar mechanism to its control of leaf size. Based on the recent work on SPT, we propose that it is a growth repressor that acts to limit the size of meristems in response to environmental signals, perhaps by regulating auxin transport. PMID:23470719

  18. Controlling excess noise in fiber-optics continuous-variable quantum key distribution

    SciTech Connect

    Lodewyck, Jerome; Debuisschert, Thierry; Tualle-Brouri, Rosa; Grangier, Philippe

    2005-11-15

    We describe a continuous-variable coherent-states quantum-key distribution system working at 1550 nm, and entirely made of standard fiber optics and telecommunications components, such as integrated-optics modulators, couplers and fast InGaAs photodiodes. The setup is composed of an emitter randomly modulating a coherent state in the complex plane with a doubly Gaussian distribution, and a receiver based on a shot-noise limited time-resolved homodyne detector. By using a reverse reconciliation protocol, the device can transfer a raw key rate up to 1 Mbit/s, with a proven security against Gaussian or non-Gaussian attacks. The dependence of the secret information rate of the present fiber setup is studied as a function of the line transmission and excess noise.

  19. Controlling excess noise in fiber-optics continuous-variable quantum key distribution

    NASA Astrophysics Data System (ADS)

    Lodewyck, Jérôme; Debuisschert, Thierry; Tualle-Brouri, Rosa; Grangier, Philippe

    2005-11-01

    We describe a continuous-variable coherent-states quantum-key distribution system working at 1550nm , and entirely made of standard fiber optics and telecommunications components, such as integrated-optics modulators, couplers and fast InGaAs photodiodes. The setup is composed of an emitter randomly modulating a coherent state in the complex plane with a doubly Gaussian distribution, and a receiver based on a shot-noise limited time-resolved homodyne detector. By using a reverse reconciliation protocol, the device can transfer a raw key rate up to 1Mbit/s , with a proven security against Gaussian or non-Gaussian attacks. The dependence of the secret information rate of the present fiber setup is studied as a function of the line transmission and excess noise.

  20. Pioneer transcription factors, chromatin dynamics, and cell fate control.

    PubMed

    Zaret, Kenneth S; Mango, Susan E

    2016-04-01

    Among the diverse transcription factors that are necessary to elicit changes in cell fate, both in embryonic development and in cellular reprogramming, a subset of factors are capable of binding to their target sequences on nucleosomal DNA and initiating regulatory events in silent chromatin. Such 'pioneer transcription factors' initiate cooperative interactions with other regulatory proteins to elicit changes in local chromatin structure. As a consequence of pioneer factor binding, the local chromatin can either become open and competent for activation, closed and repressed, or transcriptionally active. Understanding how pioneer factors initiate chromatin dynamics and how such can be blocked at heterochromatic sites provides insights into controlling cell fate transitions at will. PMID:26826681

  1. Dynamic Key Management Schemes for Secure Group Access Control Using Hierarchical Clustering in Mobile Ad Hoc Networks

    NASA Astrophysics Data System (ADS)

    Tsaur, Woei-Jiunn; Pai, Haw-Tyng

    2008-11-01

    The applications of group computing and communication motivate the requirement to provide group access control in mobile ad hoc networks (MANETs). The operation in MANETs' groups performs a decentralized manner and accommodated membership dynamically. Moreover, due to lack of centralized control, MANETs' groups are inherently insecure and vulnerable to attacks from both within and outside the groups. Such features make access control more challenging in MANETs. Recently, several researchers have proposed group access control mechanisms in MANETs based on a variety of threshold signatures. However, these mechanisms cannot actually satisfy MANETs' dynamic environments. This is because the threshold-based mechanisms cannot be achieved when the number of members is not up to the threshold value. Hence, by combining the efficient elliptic curve cryptosystem, self-certified public key cryptosystem and secure filter technique, we construct dynamic key management schemes based on hierarchical clustering for securing group access control in MANETs. Specifically, the proposed schemes can constantly accomplish secure group access control only by renewing the secure filters of few cluster heads, when a cluster head joins or leaves a cross-cluster. In such a new way, we can find that the proposed group access control scheme can be very effective for securing practical applications in MANETs.

  2. Screening Active Components from Yu-Ping-Feng-San for Regulating Initiative Key Factors in Allergic Sensitization

    PubMed Central

    Zhu, Zhijie; Yu, Xi; Liu, Hailiang; Wang, Huizhu; Fan, Hongwei; Wang, Dawei; Jiang, Guorong; Hong, Min

    2014-01-01

    Yu-ping-feng-san (YPFS) is a Chinese medical formula that is used clinically for allergic diseases and characterized by reducing allergy relapse. Our previous studies demonstrated that YPFS efficiently inhibited T helper 2 cytokines in allergic inflammation. The underlying mechanisms of action of YPFS and its effective components remain unclear. In this study, it was shown that YPFS significantly inhibited production of thymic stromal lymphopoietin (TSLP), an epithelial cell-derived initiative factor in allergic inflammation, in vitro and in vivo. A method of human bronchial epithelial cell (16HBE) binding combined with HPLC-MS (named 16HBE-HPLC-MS) was established to explore potential active components of YPFS. The following five components bound to 16HBE cells: calycosin-7-glucoside, ononin, claycosin, sec-o-glucosylhamaudol and formononetin. Serum from YPFS-treated mice was analyzed and three major components were detected claycosin, formononetin and cimifugin. Among these, claycosin and formononetin were detected by 16HBE-HPLC-MS and in the serum of YPFS-treated mice. Claycosin and formononetin decreased the level of TSLP markedly at the initial stage of allergic inflammation in vivo. Nuclear factor (NF)-κB, a key transcription factor in TSLP production, was also inhibited by claycosin and formononetin, either in terms of transcriptional activation or its nuclear translocation in vitro. Allergic inflammation was reduced by claycosin and formononetin when they are administered only at the initial stage in a murine model of atopic contact dermatitis. Thus, epithelial cell binding combined with HPLC-MS is a valid method for screening active components from complex mixtures of Chinese medicine. It was demonstrated that the compounds screened from YPFS significantly attenuated allergic inflammation probably by reducing TSLP production via regulating NF-κB activation. PMID:25198676

  3. Expert Panel Consensus for and Analysis of Key Attributes on Websites Devoted to Weight Control

    ERIC Educational Resources Information Center

    Brown, Stephen L.; Land, Diane; Johnson, Chandrika; Miller, Kim

    2014-01-01

    Background: Obesity presents major challenges to public health in the United States. Trials of web-based interventions for weight control suggest that the Internet is a promising option for program delivery. Purpose: This study sought consensus among experts regarding critical components of successful weight control and to systematically examine…

  4. Quality-control: from record keeping to key performance indicators: manging quality in compounding pharmacies.

    PubMed

    Braga, Glaucia Karime; Fonseca, Maria Jose Viera

    2010-01-01

    Record keeping is fundamental in any quality-management system. Compounding pharmacies use a quality-management system that is based on the Good Compounding Practices, which emphasizes the necessity and therefore the importance of maintaining records. However, the activity of recording without conducting further data analysis does not assure continuous improvement of the preparations, services, and of the system itself. The purpose of this article is to suggest some nonfinancial key performance indicators that can be easily implemented by compounding pharmacies to assist in the development of an organizational procedure for measuring the quality of products and services. This is a new paradigm for managing quality in compounding pharmacies. PMID:23965425

  5. Eruption vs. storage: Key thermomechanical controls on the production of large silicic magma chambers

    NASA Astrophysics Data System (ADS)

    Jellinek, M.; Depaolo, D.

    2008-12-01

    The production of large-volume silicic magma chambers in the mid to upper crust is enigmatic: Why would buoyant and otherwise eruptible magma remain ponded at depth rather than drain to the surface roughly at the rate at which it is produced? One way that the rise and eruption of this magma can be checked is if the nucleation and/or propagation of dikes to the surface is suppressed. Additionally, if the average rate at which heat is carried in to the chamber by basaltic or silicic replenishments is insufficiently large relative to the rate of internal crystallization, the magma may become overly crystal rich and effectively "uneruptible". Bearing in mind these two mechanisms favoring chamber growth we will simple models to discuss three issues that ultimately govern whether buoyant magma becomes stored in a high-level magma chamber or erupts at the surface: 1) The long-term average supply of magma to the chamber; 2) the thermal structure, mechanical strength and background stress regime of the crust; and 3) the volume and shape of the magma chamber. For a given chamber volume, shape and cooling rate, the magma supply to a volcanic/plutonic system governs both the mean crystal content and the maximum average chamber overpressure available to propagate dikes to the surface. Whether such an overpressure can drive dike formation and propagation to the surface or lead to magma storage depends on the strength and thermal regime of surrounding crust, which depends, in turn, on their initial thermo-mechanical state and subsequent history of magmatism. In principle, even if a magmatic system is in a regime that favors eruption a very high magma supply (greater than the rates of eruption and crystallization) can ensure that magma accumulate in the crust. Thus, the most import parameter in the problem that must be constrained carefully is the magma supply. The long term magma supply is controlled primarily by the heat transfer properties of underlying mantle convection and

  6. Human factors survey of advanced instrumentation and controls

    SciTech Connect

    Carter, R.J.

    1989-01-01

    A survey oriented towards identifying the human factors issues in regard to the use of advanced instrumentation and controls (I C) in the nuclear industry was conducted. A number of United States (US) and Canadian nuclear vendors and utilities were participants in the survey. Human factors items, subsumed under the categories of computer-generated displays (CGD), controls, organizational support, training, and related topics, were discussed. The survey found the industry to be concerned about the human factors issues related to the implementation of advanced I C. Fifteen potential human factors problems were identified. They include: the need for an advanced I C guideline equivalent to NUREG-0700; a role change in the control room from operator to supervisor; information overload; adequacy of existing training technology for advanced I C; and operator acceptance and trust. 11 refs., 1 tab.

  7. Determination of Key Environmental Factors Responsible for Distribution Patterns of Fiddler Crabs in a Tropical Mangrove Ecosystem

    PubMed Central

    Mokhtari, Mohammad; Ghaffar, Mazlan Abd; Usup, Gires; Cob, Zaidi Che

    2015-01-01

    In tropical regions, different species of fiddler crabs coexist on the mangrove floor, which sometimes makes it difficult to define species-specific habitat by visual inspection. The aim of this study is to find key environmental parameters which affect the distribution of fiddler crabs and to determine the habitats in which each species was most abundant. Crabs were collected from 19 sites within the mudflats of Sepang-Lukut mangrove forest. Temperature, porewater salinity, organic matter, water content, carbon and nitrogen content, porosity, chlorophyll content, pH, redox potential, sediment texture and heavy metals were determined in each 1 m2 quadrate. Pearson correlation indicated that all sediment properties except pH and redox potential were correlated with sediment grain size. Canonical correspondence analysis (CCA) indicated that Uca paradussumieri was negatively correlated with salinity and redox potential. Sand dwelling species, Uca perplexa and Uca annulipes, were highly dependent on the abundance of 250 μm and 150 μm grain size particles in the sediment. Canonical Discriminative Analysis (CDA) indicated that variation in sediment grain size best explained where each crab species was most abundant. Moreover, U. paradussumieri commonly occupies muddy substrates of low shore, while U. forcipata lives under the shade of mangrove trees. U. annulipes and U. perplexa with the high number of spoon tipped setae on their second maxiliped are specialized to feed on the sandy sediments. U. rosea and U. triangularis are more common on muddy sediment with high sediment density. In conclusion, sediment grain size that influences most sediment properties acts as a main factor responsible for sediment heterogeneity. In this paper, the correlation between fiddler crab species and environmental parameters, as well as the interaction between sediment characteristics, was explained in order to define the important environmental factors in fiddler crab distributions. PMID

  8. Identification of Key Factors Involved in the Biosorption of Patulin by Inactivated Lactic Acid Bacteria (LAB) Cells

    PubMed Central

    Wang, Ling; Wang, Zhouli; Yuan, Yahong; Cai, Rui; Niu, Chen; Yue, Tianli

    2015-01-01

    The purpose of this study was to identify the key factors involved in patulin adsorption by heat-inactivated lactic acid bacteria (LAB) cells. For preventing bacterial contamination, a sterilization process was involved in the adsorption process. The effects of various physical, chemical, and enzymatic pre-treatments, simultaneous treatments, and post-treatments on the patulin adsorption performances of six LAB strains were evaluated. The pre-treated cells were characterized by scanning electron microscopy (SEM). Results showed that the removal of patulin by viable cells was mainly based on adsorption or degradation, depending on the specific strain. The adsorption abilities were widely increased by NaOH and esterification pre-treatments, and reduced by trypsin, lipase, iodate, and periodate pre-treatments. Additionally, the adsorption abilities were almost maintained at pH 2.2–4.0, and enhanced significantly at pH 4.0–6.0. The effects of sodium and magnesium ions on the adsorption abilities at pH 4 were slight and strain-specific. A lower proportion of patulin was released from the strain with higher adsorption ability. Analyses revealed that the physical structure of peptidoglycan was not a principal factor. Vicinal OH and carboxyl groups were not involved in patulin adsorption, while alkaline amino acids, thiol and ester compounds were important for patulin adsorption. Additionally, besides hydrophobic interaction, electrostatic interaction also participated in patulin adsorption, which was enhanced with the increase in pH (4.0–6.0). PMID:26581099

  9. Determination of key environmental factors responsible for distribution patterns of fiddler crabs in a tropical mangrove ecosystem.

    PubMed

    Mokhtari, Mohammad; Ghaffar, Mazlan Abd; Usup, Gires; Cob, Zaidi Che

    2015-01-01

    In tropical regions, different species of fiddler crabs coexist on the mangrove floor, which sometimes makes it difficult to define species-specific habitat by visual inspection. The aim of this study is to find key environmental parameters which affect the distribution of fiddler crabs and to determine the habitats in which each species was most abundant. Crabs were collected from 19 sites within the mudflats of Sepang-Lukut mangrove forest. Temperature, porewater salinity, organic matter, water content, carbon and nitrogen content, porosity, chlorophyll content, pH, redox potential, sediment texture and heavy metals were determined in each 1 m2 quadrate. Pearson correlation indicated that all sediment properties except pH and redox potential were correlated with sediment grain size. Canonical correspondence analysis (CCA) indicated that Uca paradussumieri was negatively correlated with salinity and redox potential. Sand dwelling species, Uca perplexa and Uca annulipes, were highly dependent on the abundance of 250 μm and 150 μm grain size particles in the sediment. Canonical Discriminative Analysis (CDA) indicated that variation in sediment grain size best explained where each crab species was most abundant. Moreover, U. paradussumieri commonly occupies muddy substrates of low shore, while U. forcipata lives under the shade of mangrove trees. U. annulipes and U. perplexa with the high number of spoon tipped setae on their second maxiliped are specialized to feed on the sandy sediments. U. rosea and U. triangularis are more common on muddy sediment with high sediment density. In conclusion, sediment grain size that influences most sediment properties acts as a main factor responsible for sediment heterogeneity. In this paper, the correlation between fiddler crab species and environmental parameters, as well as the interaction between sediment characteristics, was explained in order to define the important environmental factors in fiddler crab distributions. PMID

  10. Identifying key processes in the hydrochemistry of a basin through the combined use of factor and regression models

    NASA Astrophysics Data System (ADS)

    Yidana, Sandow Mark; Banoeng-Yakubo, Bruce; Sakyi, Patrick Asamoah

    2012-04-01

    An innovative technique of measuring the intensities of major sources of variation in the hydrochemistry of (ground) water in a basin has been developed. This technique, which is based on the combination of R-mode factor and multiple regression analyses, can be used to measure the degrees of influence of the major sources of variation in the hydrochemistry without measuring the concentrations of the entire set of physico-chemical parameters which are often used to characterize water systems. R-mode factor analysis was applied to the data of 13 physico-chemical parameters and 50 samples in order to determine the major sources of variation in the hydrochemistry of some aquifers in the western region of Ghana. In this study, three sources of variation in the hydrochemistry were distinguished: the dissolution of chlorides and sulfates of the major cations, carbonate mineral dissolution, and silicate mineral weathering. Two key parameters were identified with each of the processes and multiple regression models were developed for each process. These models were tested and found to predict these processes quite accurately, and can be applied anywhere within the terrain. This technique can be reliably applied in areas where logistical constraints limit water sampling for whole basin hydrochemical characterization. Q-mode hierarchical cluster analysis (HCA) applied to the data revealed three major groundwater associations distinguished on the basis of the major causes of variation in the hydrochemistry. The three groundwater types represent Na-HCO3, Ca-HCO3, and Na-Cl groundwater types. Silicate stability diagrams suggest that all these groundwater types are mainly stable in the kaolinite and montmorillonite fields suggesting moderately restricted flow conditions.

  11. Study of key factors influencing dust emission: An assessment of GEOS-Chem and DEAD simulations with observations

    NASA Astrophysics Data System (ADS)

    Bartlett, Kevin S.

    Mineral dust aerosols can impact air quality, climate change, biological cycles, tropical cyclone development and flight operations due to reduced visibility. Dust emissions are primarily limited to the extensive arid regions of the world, yet can negatively impact local to global scales, and are extremely complex to model accurately. Within this dissertation, the Dust Entrainment And Deposition (DEAD) model was adapted to run, for the first known time, using high temporal (hourly) and spatial (0.3°x0.3°) resolution data to methodically interrogate the key parameters and factors influencing global dust emissions. The dependence of dust emissions on key parameters under various conditions has been quantified and it has been shown that dust emissions within DEAD are largely determined by wind speeds, vegetation extent, soil moisture and topographic depressions. Important findings were that grid degradation from 0.3ºx0.3º to 1ºx1º, 2ºx2.5º, and 4°x5° of key meteorological, soil, and surface input parameters greatly reduced emissions approximately 13% and 29% and 64% respectively, as a result of the loss of sub grid detail within these key parameters at coarse grids. After running high resolution DEAD emissions globally for 2 years, two severe dust emission cases were chosen for an in-depth investigation of the root causes of the events and evaluation of the 2°x2.5° Goddard Earth Observing System (GEOS)-Chem and 0.3°x0.3° DEAD model capabilities to simulate the events: one over South West Asia (SWA) in June 2008 and the other over the Middle East in July 2009. The 2 year lack of rain over SWA preceding June 2008 with a 43% decrease in mean rainfall, yielded less than normal plant growth, a 28% increase in Aerosol Optical Depth (AOD), and a 24% decrease in Meteorological Aerodrome Report (METAR) observed visibility (VSBY) compared to average years. GEOS-Chem captured the observed higher AOD over SWA in June 2008. More detailed comparisons of GEOS

  12. Research on Key Factors and Their Interaction Effects of Electromagnetic Force of High-Speed Solenoid Valve

    PubMed Central

    Fan, Liyun; Xu, De; Ma, Xiuzhen; Song, Enzhe

    2014-01-01

    Analysis consisting of numerical simulations along with lab experiments of interaction effects between key parameters on the electromagnetic force based on response surface methodology (RSM) has been also proposed to optimize the design of high-speed solenoid valve (HSV) and improve its performance. Numerical simulation model of HSV has been developed in Ansoft Maxwell environment and its accuracy has been validated through lab experiments. Effect of change of core structure, coil structure, armature structure, working air gap, and drive current on the electromagnetic force of HSV has been analyzed through simulation model and influence rules of various parameters on the electromagnetic force have been established. The response surface model of the electromagnetic force has been utilized to analyze the interaction effect between major parameters. It has been concluded that six interaction factors including working air gap with armature radius, drive current with armature thickness, coil turns with side pole radius, armature thickness with its radius, armature thickness with side pole radius, and armature radius with side pole radius have significant influence on the electromagnetic force. Optimal match values between coil turns and side pole radius; armature thickness and side pole radius; and armature radius and side pole radius have also been determined. PMID:25243217

  13. A host basal transcription factor is a key component for infection of rice by TALE-carrying bacteria

    PubMed Central

    Yuan, Meng; Ke, Yinggen; Huang, Renyan; Ma, Ling; Yang, Zeyu; Chu, Zhaohui; Xiao, Jinghua; Li, Xianghua; Wang, Shiping

    2016-01-01

    Transcription activator-like effectors (TALEs) are sequence-specific DNA binding proteins found in a range of plant pathogenic bacteria, where they play important roles in host-pathogen interactions. However, it has been unclear how TALEs, after they have been injected into the host cells, activate transcription of host genes required for infection success. Here, we show that the basal transcription factor IIA gamma subunit TFIIAγ5 from rice is a key component for infection by the TALE-carrying bacterium Xanthomonas oryzae pv. oryzae, the causal agent for bacterial blight. Direct interaction of several TALEs with TFIIAγ5 is required for activation of disease susceptibility genes. Conversely, reduced expression of the TFIIAγ5 host gene limits the induction of susceptibility genes and thus decreases bacterial blight symptoms. Suppression or mutation of TFIIAγ5 can also reduce bacterial streak, another devastating disease of rice caused by TALE-carrying X. oryzae pv. oryzicola. These results have important implications for formulating a widely applicable strategy with which to improve resistance of plants to TALE-carrying pathogens. DOI: http://dx.doi.org/10.7554/eLife.19605.001 PMID:27472897

  14. Proton Gradients as a Key Physical Factor in the Evolution of the Forced Transport Mechanism Across the Lipid Membrane

    NASA Astrophysics Data System (ADS)

    Strbak, Oliver; Kanuchova, Zuzana; Krafcik, Andrej

    2016-04-01

    A critical phase in the transition from prebiotic chemistry to biological evolution was apparently an asymmetric ion flow across the lipid membrane. Due to imbalance in the ion flow, the early lipid vesicles could selectively take the necessary molecules from the environment, and release the side-products from the vesicle. Natural proton gradients played a definitively crucial role in this process, since they remain the basis of energy transfer in the present-day cells. On the basis of this supposition, and the premise of the early vesicle membrane's impermeability to protons, we have shown that the emergence of the proton gradient in the lipid vesicle could be a key physical factor in the evolution of the forced transport mechanism (pore formation and active transport) across the lipid bilayer. This driven flow of protons across the membrane is the result of the electrochemical proton gradient and osmotic pressures on the integrity of the lipid vesicle. At a critical number of new lipid molecules incorporated into the vesicle, the energies associated with the creation of the proton gradient exceed the bending stiffness of the lipid membrane, and overlap the free energy of the lipid bilayer pore formation.

  15. A host basal transcription factor is a key component for infection of rice by TALE-carrying bacteria.

    PubMed

    Yuan, Meng; Ke, Yinggen; Huang, Renyan; Ma, Ling; Yang, Zeyu; Chu, Zhaohui; Xiao, Jinghua; Li, Xianghua; Wang, Shiping

    2016-01-01

    Transcription activator-like effectors (TALEs) are sequence-specific DNA binding proteins found in a range of plant pathogenic bacteria, where they play important roles in host-pathogen interactions. However, it has been unclear how TALEs, after they have been injected into the host cells, activate transcription of host genes required for infection success. Here, we show that the basal transcription factor IIA gamma subunit TFIIAγ5 from rice is a key component for infection by the TALE-carrying bacterium Xanthomonas oryzae pv. oryzae, the causal agent for bacterial blight. Direct interaction of several TALEs with TFIIAγ5 is required for activation of disease susceptibility genes. Conversely, reduced expression of the TFIIAγ5 host gene limits the induction of susceptibility genes and thus decreases bacterial blight symptoms. Suppression or mutation of TFIIAγ5 can also reduce bacterial streak, another devastating disease of rice caused by TALE-carrying X. oryzae pv. oryzicola. These results have important implications for formulating a widely applicable strategy with which to improve resistance of plants to TALE-carrying pathogens. PMID:27472897

  16. Two separate key enzymes and two pathway-specific transcription factors are involved in fusaric acid biosynthesis in Fusarium fujikuroi.

    PubMed

    Studt, Lena; Janevska, Slavica; Niehaus, Eva-Maria; Burkhardt, Immo; Arndt, Birgit; Sieber, Christian M K; Humpf, Hans-Ulrich; Dickschat, Jeroen S; Tudzynski, Bettina

    2016-03-01

    Fusaric acid (FSA) is a mycotoxin produced by several fusaria, including the rice pathogen Fusarium fujikuroi. Genes involved in FSA biosynthesis were previously identified as a cluster containing a polyketide synthase (PKS)-encoding (FUB1) and four additional genes (FUB2-FUB5). However, the biosynthetic steps leading to FSA as well as the origin of the nitrogen atom, which is incorporated into the polyketide backbone, remained unknown. In this study, seven additional cluster genes (FUB6-FUB12) were identified via manipulation of the global regulator FfSge1. The extended FUB gene cluster encodes two Zn(II)2 Cys6 transcription factors: Fub10 positively regulates expression of all FUB genes, whereas Fub12 is involved in the formation of the two FSA derivatives, i.e. dehydrofusaric acid and fusarinolic acid, serving as a detoxification mechanism. The major facilitator superfamily transporter Fub11 functions in the export of FSA out of the cell and is essential when FSA levels become critical. Next to Fub1, a second key enzyme was identified, the non-canonical non-ribosomal peptide synthetase Fub8. Chemical analyses of generated mutant strains allowed for the identification of a triketide as PKS product and the proposition of an FSA biosynthetic pathway, thereby unravelling the unique formation of a hybrid metabolite consisting of this triketide and an amino acid moiety. PMID:26662839

  17. Key Factors in the Rise of Mass Popular Education and Their Relevance for Education in Southern Africa in the Twenty-First Century.

    ERIC Educational Resources Information Center

    van Niekerk, E. J.

    This paper identifies the historical factors that played a key role in the rise of mass popular education and describes how these factors relate to education in Southern Africa in the 21st century. The broad overview of developments since the Renaissance begins with the Protestant Reformation, which established a theoretical basis for elementary…

  18. Protein Adsorption as a Key Mediator in the Nanotopographical Control of Cell Behavior.

    PubMed

    Ngandu Mpoyi, Elie; Cantini, Marco; Reynolds, Paul M; Gadegaard, Nikolaj; Dalby, Matthew J; Salmerón-Sánchez, Manuel

    2016-07-26

    Surface nanotopography is widely employed to control cell behavior and in particular controlled disorder has been shown to be important in cell differentiation/maturation. However, extracellular matrix proteins, such as fibronectin (FN), initially adsorbed on a biomaterial surface are known to mediate the interaction of synthetic materials with cells. In this work, we examine the effect of nanotopography on cell behavior through this adsorbed layer of adhesive proteins using a nanostructured polycarbonate surface comprising 150 nm-diameter pits originally defined using electron beam lithography. We address the effect of this nanopitted surface on FN adsorption and subsequently on cell morphology and behavior using C2C12 myoblasts. Wettability measurements and atomic force microscopy imaging showed that protein is adsorbed both within the interpits spaces and inside the nanopits. Cells responded to this coated nanotopography with the formation of fewer but larger focal adhesions and by mimicking the pit patterns within their cytoskeleton, nanoimprinting, ultimately achieving higher levels of myogenic differentiation compared to a flat control. Both focal adhesion assembly and nanoimprinting were found to be dependent on cell contractility and are adversely affected by the use of blebbistatin. Our results demonstrate the central role of the nanoscale protein interface in mediating cell-nanotopographical interactions and implicate this interface as helping control the mechanotransductive cascade. PMID:27391047

  19. High-temperature adult-plant resistance, the key for sustainable control of stripe rust

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High-temperature adult-plant (HTAP) resistance expresses when plants grow old and the weather becomes warm. This non-race specific and durable type of resistance has been used successfully in control of wheat stripe rust in the U.S. since early 1960s. This article describes practical procedures f...

  20. Deconstructing the Instruction of the Control of Variables Strategy: Key Components of Science Instruction

    ERIC Educational Resources Information Center

    Freer, Benjamin D.; Lorch, Elizabeth P.; Lorch, Robert F., Jr.; Calderhead, William

    2011-01-01

    A crucial element of the logic of the scientific method is the Control of Variables Strategy (CVS), in which conclusions about causal relations are enabled by manipulating a focal variable of interest while holding all other variables constant. Understanding CVS in elementary grades generally is poor, but can be improved with systematic…

  1. Protein Adsorption as a Key Mediator in the Nanotopographical Control of Cell Behavior

    PubMed Central

    2016-01-01

    Surface nanotopography is widely employed to control cell behavior and in particular controlled disorder has been shown to be important in cell differentiation/maturation. However, extracellular matrix proteins, such as fibronectin (FN), initially adsorbed on a biomaterial surface are known to mediate the interaction of synthetic materials with cells. In this work, we examine the effect of nanotopography on cell behavior through this adsorbed layer of adhesive proteins using a nanostructured polycarbonate surface comprising 150 nm-diameter pits originally defined using electron beam lithography. We address the effect of this nanopitted surface on FN adsorption and subsequently on cell morphology and behavior using C2C12 myoblasts. Wettability measurements and atomic force microscopy imaging showed that protein is adsorbed both within the interpits spaces and inside the nanopits. Cells responded to this coated nanotopography with the formation of fewer but larger focal adhesions and by mimicking the pit patterns within their cytoskeleton, nanoimprinting, ultimately achieving higher levels of myogenic differentiation compared to a flat control. Both focal adhesion assembly and nanoimprinting were found to be dependent on cell contractility and are adversely affected by the use of blebbistatin. Our results demonstrate the central role of the nanoscale protein interface in mediating cell-nanotopographical interactions and implicate this interface as helping control the mechanotransductive cascade. PMID:27391047

  2. Infection Control for Drug-Resistant Tuberculosis: Early Diagnosis and Treatment Is the Key.

    PubMed

    van Cutsem, Gilles; Isaakidis, Petros; Farley, Jason; Nardell, Ed; Volchenkov, Grigory; Cox, Helen

    2016-05-15

    Multidrug-resistant (MDR) tuberculosis, "Ebola with wings," is a significant threat to tuberculosis control efforts. Previous prevailing views that resistance was mainly acquired through poor treatment led to decades of focus on drug-sensitive rather than drug-resistant (DR) tuberculosis, driven by the World Health Organization's directly observed therapy, short course strategy. The paradigm has shifted toward recognition that most DR tuberculosis is transmitted and that there is a need for increased efforts to control DR tuberculosis. Yet most people with DR tuberculosis are untested and untreated, driving transmission in the community and in health systems in high-burden settings. The risk of nosocomial transmission is high for patients and staff alike. Lowering transmission risk for MDR tuberculosis requires a combination approach centered on rapid identification of active tuberculosis disease and tuberculosis drug resistance, followed by rapid initiation of appropriate treatment and adherence support, complemented by universal tuberculosis infection control measures in healthcare facilities. It also requires a second paradigm shift, from the classic infection control hierarchy to a novel, decentralized approach across the continuum from early diagnosis and treatment to community awareness and support. A massive scale-up of rapid diagnosis and treatment is necessary to control the MDR tuberculosis epidemic. This will not be possible without intense efforts toward the implementation of decentralized, ambulatory models of care. Increasing political will and resources need to be accompanied by a paradigm shift. Instead of focusing on diagnosed cases, recognition that transmission is driven largely by undiagnosed, untreated cases, both in the community and in healthcare settings, is necessary. This article discusses this comprehensive approach, strategies available, and associated challenges. PMID:27118853

  3. Motor power factor controller with a reduced voltage starter

    NASA Technical Reports Server (NTRS)

    Nola, Frank J. (Inventor)

    1983-01-01

    A power factor type motor controller in which the conventional power factor constant voltage command signal is replaced during a starting interval with a graduated control voltage. The present invention adds to the three-phase system of pending application Ser. No. 199,765, filed Oct. 23, 1980, means for modifying the operation of the system for a motor start-up interval of 5 to 30 seconds. The modification is that of providing via ramp generator 174 an initial ramp-like signal which replaces a constant power factor signal supplied by potentiometer 70. The ramp-like signal is applied to terminal 40 where it is summed with an operating power factor signal from phase detectors 32, 34, and 36 to thereby obtain a control signal for ultimately controlling SCR devices 12, 14, and 16 to effect a gradual turn-on of motor 10. The significant difference of the present invention over prior art is that the SCR devices are turned on at an advancing rate with time responsive to the combination signal described rather than simply a function of a ramp-like signal alone. The added signal, the operating power factor signal, enables the production of a control signal which effectively eliminates a prior problem with many motor starting circuits, which is that of accompanying motor instabilities.

  4. A key developmental regulator controls the synthesis of the antibiotic erythromycin in Saccharopolyspora erythraea.

    PubMed

    Chng, Chinping; Lum, Amy M; Vroom, Jonathan A; Kao, Camilla M

    2008-08-12

    Saccharopolyspora erythraea makes erythromycin, an antibiotic commonly used in human medicine. Unusually, the erythromycin biosynthetic (ery) cluster lacks a pathway-specific regulatory gene. We isolated a transcriptional regulator of the ery biosynthetic genes from S. erythraea and found that this protein appears to directly link morphological changes caused by impending starvation to the synthesis of a molecule that kills other bacteria, i.e., erythromycin. DNA binding assays, liquid and affinity chromatography, MALDI-MS analysis, and de novo sequencing identified this protein (M(r) = 18 kDa) as the S. erythraea ortholog of BldD, a key regulator of development in Streptomyces coelicolor. Recombinant S. erythraea BldD bound to all five regions containing promoters in the ery cluster as well as to its own promoter, the latter with an order-of-magnitude stronger than to the ery promoters. Deletion of bldD in S. erythraea decreased the erythromycin titer in a liquid culture 7-fold and blocked differentiation on a solid medium. Moreover, an industrial strain of S. erythraea with a higher titer of erythromycin expressed more BldD than a wild-type strain during erythromycin synthesis. Together, these results suggest that BldD concurrently regulates the synthesis of erythromycin and morphological differentiation. The ery genes are the first direct targets of a BldD ortholog to be identified that are positively regulated. PMID:18685110

  5. A key developmental regulator controls the synthesis of the antibiotic erythromycin in Saccharopolyspora erythraea

    PubMed Central

    Chng, Chinping; Lum, Amy M.; Vroom, Jonathan A.; Kao, Camilla M.

    2008-01-01

    Saccharopolyspora erythraea makes erythromycin, an antibiotic commonly used in human medicine. Unusually, the erythromycin biosynthetic (ery) cluster lacks a pathway-specific regulatory gene. We isolated a transcriptional regulator of the ery biosynthetic genes from S. erythraea and found that this protein appears to directly link morphological changes caused by impending starvation to the synthesis of a molecule that kills other bacteria, i.e., erythromycin. DNA binding assays, liquid and affinity chromatography, MALDI-MS analysis, and de novo sequencing identified this protein (Mr = 18 kDa) as the S. erythraea ortholog of BldD, a key regulator of development in Streptomyces coelicolor. Recombinant S. erythraea BldD bound to all five regions containing promoters in the ery cluster as well as to its own promoter, the latter with an order-of-magnitude stronger than to the ery promoters. Deletion of bldD in S. erythraea decreased the erythromycin titer in a liquid culture 7-fold and blocked differentiation on a solid medium. Moreover, an industrial strain of S. erythraea with a higher titer of erythromycin expressed more BldD than a wild-type strain during erythromycin synthesis. Together, these results suggest that BldD concurrently regulates the synthesis of erythromycin and morphological differentiation. The ery genes are the first direct targets of a BldD ortholog to be identified that are positively regulated. PMID:18685110

  6. Selenium deficiency and thyroid fibrosis. A key role for macrophages and transforming growth factor beta (TGF-beta).

    PubMed

    Contempre, B; Le Moine, O; Dumont, J E; Denef, J F; Many, M C

    1996-11-29

    Free radical damage and fibrosis caused by selenium deficiency are thought to be involved in the pathogenesis of myxoedematous cretinism. So far, no pathway explains the link between selenium deficiency and tissue fibrosis. Pharmacological doses of iodine induce necrosis in iodine-deficient thyroids. Necrosis is much increased if the glands are also selenium-deficient, which then evolve to fibrosis. This rat model was reproduced to explore the role of selenium deficiency in defective tissue repair. At first, proliferation indexes of epithelial cells and fibroblasts were comparable between selenium-deficient and control groups. Then, in selenium-deficient thyroids the inflammatory reaction was more marked being mainly composed of macrophages. The proliferation index of the epithelial cells decreased, while that of the fibroblasts increased. These thyroids evolved to fibrosis. TGF-beta immunostaining was prominent in the macrophages of selenium-deficient rats. Anti TGF-beta antibodies restored the proliferation indexes, and blocked the evolution to fibrosis. In selenium deficiency, an active fibrotic process occurs in the thyroid, in which the inflammatory reaction and an excess of TGF-beta play a key role. PMID:9027319

  7. Three key regions for supervisory attentional control: Evidence from neuroimaging meta-analyses

    PubMed Central

    Cieslik, Edna C.; Mueller, Veronika I.; Eickhoff, Claudia R.; Langner, Robert; Eickhoff, Simon B.

    2014-01-01

    The supervisory attentional system has been proposed to mediate non-routine, goal-oriented behaviour by guiding the selection and maintenance of the goal-relevant task schema. Here, we aimed to delineate the brain regions that mediate these high-level control processes via neuroimaging meta-analysis. In particular, we investigated the core neural correlates of a wide range of tasks requiring supervisory control for the suppression of a routine action in favour of another, non-routine one. Our sample comprised n = 173 experiments employing go/no-go, stop-signal, Stroop or spatial interference tasks. Consistent convergence across all four paradigm classes was restricted to right anterior insula and inferior frontal junction, with anterior midcingulate cortex and pre-supplementary motor area being consistently involved in all but the go/no-go task. Taken together with lesion studies in patients, our findings suggest that the controlled activation and maintenance of adequate task schemata relies, across paradigms, on a right-dominant midcingulo-insular-inferior frontal core network. This also implies that the role of other prefrontal and parietal regions may be less domain-general than previously thought. PMID:25446951

  8. Controllers and Pilots Play a Key Role in Runway Safety Initiatives Through Real-Time Simulation

    NASA Technical Reports Server (NTRS)

    Madson, Mike; Bender, Kim

    2004-01-01

    A new and innovative way to evaluate runway safety initiatives for airports is through the use of interactive real-time simulation. The National Aeronautics and Space Administration (NASA) operates an integrated suite of simulators that can give both pilots and tower controllers the ability to simultaneously "try out" ideas in the safety of virtual reality. In February of 2003, the FAA conducted a demonstration in the NASA facilities for Dallas/Fort Worth International Airport (DFW) of a concept to reduce runway crossings and enhance the efficiency of the airport. Currently DFW experiences about 1,700 runway crossings per day, which contribute to arrival and departure delays and the potential for runway incursions. The proposed concept included the addition of new perimeter taxiways on the East and West sides of the airport. Through use of NASA's unique simulation capabilities, DFW controllers and commercial pilots provided expert feedback on the safety and operational implications by directly experiencing the proposed changes. Overall, the data collected from the participants and the simulators demonstrated that the concept would improve operations at DFW, if implemented. Improvements were observed in many areas including departure rates, taxi duration, runway crossings, and controller and pilot communications.

  9. The mechanosensory calcium-selective ion channel: key component of a plasmalemmal control centre?

    NASA Technical Reports Server (NTRS)

    Pickard, B. G.; Ding, J. P.

    1993-01-01

    Mechanosensory calcium-selective ion channels probably serve to detect not only mechanical stress but also electrical, thermal, and diverse chemical stimuli. Because all stimuli result in a common output, most notably a shift in second messenger calcium concentration, the channels are presumed to serve as signal integrators. Further, insofar as second messenger calcium in turn gives rise to mechanical, electrical, and diverse chemical changes, the channels are postulated to initiate regulatory feedbacks. It is proposed that the channels and the feedback loops play a wide range of roles in regulating normal plant function, as well as in mediating disturbance of normal function by environmental stressors and various pathogens. In developing evidence for the physiological performance of the channel, a model for a cluster of regulatory plasmalemmal proteins and cytoskeletal elements grouped around a set of wall-to-membrane and transmembrane linkers has proved useful. An illustration of how the model might operate is presented. It is founded on the demonstration that several xenobiotics interfere both with normal channel behaviour and with gravitropic reception. Accordingly, the first part of the illustration deals with how the channels and the control system within which they putatively operate might initiate gravitropism. Assuming that gravitropism is an asymmetric expression of growth, the activities of the channels and the plasmalemmal control system are extrapolated to account for regulation of both rate and allometry of cell expansion. Finally, it is discussed how light, hormones, redox agents and herbicides could in principle affect growth via the putative plasmalemmal control cluster or centre.

  10. The Circadian Clock in Murine Chondrocytes Regulates Genes Controlling Key Aspects of Cartilage Homeostasis

    PubMed Central

    Gossan, Nicole; Zeef, Leo; Hensman, James; Hughes, Alun; Bateman, John F; Rowley, Lynn; Little, Christopher B; Piggins, Hugh D; Rattray, Magnus; Boot-Handford, Raymond P; Meng, Qing-Jun

    2013-01-01

    ObjectiveTo characterize the circadian clock in murine cartilage tissue and identify tissue-specific clock target genes, and to investigate whether the circadian clock changes during aging or during cartilage degeneration using an experimental mouse model of osteoarthritis (OA). MethodsCartilage explants were obtained from aged and young adult mice after transduction with the circadian clock fusion protein reporter PER2::luc, and real-time bioluminescence recordings were used to characterize the properties of the clock. Time-series microarrays were performed on mouse cartilage tissue to identify genes expressed in a circadian manner. Rhythmic genes were confirmed by quantitative reverse transcription–polymerase chain reaction using mouse tissue, primary chondrocytes, and a human chondrocyte cell line. Experimental OA was induced in mice by destabilization of the medial meniscus (DMM), and articular cartilage samples were microdissected and subjected to microarray analysis. ResultsMouse cartilage tissue and a human chondrocyte cell line were found to contain intrinsic molecular circadian clocks. The cartilage clock could be reset by temperature signals, while the circadian period was temperature compensated. PER2::luc bioluminescence demonstrated that circadian oscillations were significantly lower in amplitude in cartilage from aged mice. Time-series microarray analyses of the mouse tissue identified the first circadian transcriptome in cartilage, revealing that 615 genes (∼3.9% of the expressed genes) displayed a circadian pattern of expression. This included genes involved in cartilage homeostasis and survival, as well as genes with potential importance in the pathogenesis of OA. Several clock genes were disrupted in the early stages of cartilage degeneration in the DMM mouse model of OA. ConclusionThese results reveal an autonomous circadian clock in chondrocytes that can be implicated in key aspects of cartilage biology and pathology. Consequently

  11. Role of GnRH Neurons and Their Neuronal Afferents as Key Integrators between Food Intake Regulatory Signals and the Control of Reproduction.

    PubMed

    Roa, Juan

    2013-01-01

    Reproductive function is regulated by a plethora of signals that integrate physiological and environmental information. Among others, metabolic factors are key components of this circuit since they inform about the propitious timing for reproduction depending on energy availability. This information is processed mainly at the hypothalamus that, in turn, modulates gonadotropin release from the pituitary and, thereby, gonadal activity. Metabolic hormones, such as leptin, insulin, and ghrelin, act as indicators of the energy status and convey this information to the reproductive axis regulating its activity. In this review, we will analyse the central mechanisms involved in the integration of this metabolic information and their contribution to the control of the reproductive function. Particular attention will be paid to summarize the participation of GnRH, Kiss1, NPY, and POMC neurons in this process and their possible interactions to contribute to the metabolic control of reproduction. PMID:24101924

  12. Role of GnRH Neurons and Their Neuronal Afferents as Key Integrators between Food Intake Regulatory Signals and the Control of Reproduction

    PubMed Central

    2013-01-01

    Reproductive function is regulated by a plethora of signals that integrate physiological and environmental information. Among others, metabolic factors are key components of this circuit since they inform about the propitious timing for reproduction depending on energy availability. This information is processed mainly at the hypothalamus that, in turn, modulates gonadotropin release from the pituitary and, thereby, gonadal activity. Metabolic hormones, such as leptin, insulin, and ghrelin, act as indicators of the energy status and convey this information to the reproductive axis regulating its activity. In this review, we will analyse the central mechanisms involved in the integration of this metabolic information and their contribution to the control of the reproductive function. Particular attention will be paid to summarize the participation of GnRH, Kiss1, NPY, and POMC neurons in this process and their possible interactions to contribute to the metabolic control of reproduction. PMID:24101924

  13. An effective and secure key-management scheme for hierarchical access control in E-medicine system.

    PubMed

    Odelu, Vanga; Das, Ashok Kumar; Goswami, Adrijit

    2013-04-01

    Recently several hierarchical access control schemes are proposed in the literature to provide security of e-medicine systems. However, most of them are either insecure against 'man-in-the-middle attack' or they require high storage and computational overheads. Wu and Chen proposed a key management method to solve dynamic access control problems in a user hierarchy based on hybrid cryptosystem. Though their scheme improves computational efficiency over Nikooghadam et al.'s approach, it suffers from large storage space for public parameters in public domain and computational inefficiency due to costly elliptic curve point multiplication. Recently, Nikooghadam and Zakerolhosseini showed that Wu-Chen's scheme is vulnerable to man-in-the-middle attack. In order to remedy this security weakness in Wu-Chen's scheme, they proposed a secure scheme which is again based on ECC (elliptic curve cryptography) and efficient one-way hash function. However, their scheme incurs huge computational cost for providing verification of public information in the public domain as their scheme uses ECC digital signature which is costly when compared to symmetric-key cryptosystem. In this paper, we propose an effective access control scheme in user hierarchy which is only based on symmetric-key cryptosystem and efficient one-way hash function. We show that our scheme reduces significantly the storage space for both public and private domains, and computational complexity when compared to Wu-Chen's scheme, Nikooghadam-Zakerolhosseini's scheme, and other related schemes. Through the informal and formal security analysis, we further show that our scheme is secure against different attacks and also man-in-the-middle attack. Moreover, dynamic access control problems in our scheme are also solved efficiently compared to other related schemes, making our scheme is much suitable for practical applications of e-medicine systems. PMID:23392626

  14. RNA Quality Control as a Key to Suppressing RNA Silencing of Endogenous Genes in Plants.

    PubMed

    Liu, Lin; Chen, Xuemei

    2016-06-01

    RNA quality control of endogenous RNAs is an integral part of eukaryotic gene expression and often relies on exonucleolytic degradation to eliminate dysfunctional transcripts. In parallel, exogenous and selected endogenous RNAs are degraded through RNA silencing, which is a genome defense mechanism used by many eukaryotes. In plants, RNA silencing is triggered by the production of double-stranded RNAs (dsRNAs) by RNA-DEPENDENT RNA POLYMERASEs (RDRs) and proceeds through small interfering (si) RNA-directed, ARGONAUTE (AGO)-mediated cleavage of homologous transcripts. Many studies revealed that plants avert inappropriate posttranscriptional gene silencing of endogenous coding genes by using RNA surveillance mechanisms as a safeguard to protect their transcriptome profiles. The tug of war between RNA surveillance and RNA silencing ensures the appropriate partitioning of endogenous RNA substrates among these degradation pathways. Here we review recent advances on RNA quality control and its role in the suppression of RNA silencing at endogenous genes and discuss the mechanisms underlying the crosstalk among these pathways. PMID:27045817

  15. Identification of the Key Weather Factors Affecting Overwintering Success of Apolygus lucorum Eggs in Dead Host Tree Branches

    PubMed Central

    Pan, Hongsheng; Liu, Bing; Lu, Yanhui; Desneux, Nicolas

    2014-01-01

    Understanding the effects of weather on insect population dynamics is crucial to simulate and forecast pest outbreaks, which is becoming increasingly important with the effects of climate change. The mirid bug Apolygus lucorum is an important pest on cotton, fruit trees and other crops in China, and primarily lays its eggs on dead parts of tree branches in the fall for subsequent overwintering. As such, the eggs that hatch the following spring are most strongly affected by ambient weather factors, rather than by host plant biology. In this study, we investigated the effects of three major weather factors: temperature, relative humidity and rainfall, on the hatching rate of A. lucorum eggs overwintering on dead branches of Chinese date tree (Ziziphus jujuba). Under laboratory conditions, rainfall (simulated via soaking) was necessary for the hatching of overwintering A. lucorum eggs. In the absence of rainfall (unsoaked branches), very few nymphs successfully emerged under any of the tested combinations of temperature and relative humidity. In contrast, following simulated rainfall, the hatching rate of the overwintering eggs increased dramatically. Hatching rate and developmental rate were positively correlated with relative humidity and temperature, respectively. Under field conditions, the abundance of nymphs derived from overwintering eggs was positively correlated with rainfall amount during the spring seasons of 2009–2013, while the same was not true for temperature and relative humidity. Overall, our findings indicate that rainfall is the most important factor affecting the hatching rate of overwintering A. lucorum eggs on dead plant parts and nymph population levels during the spring season. It provides the basic information for precisely forecasting the emergence of A. lucorum and subsequently timely managing its population in spring, which will make it possible to regional control of this insect pest widely occurring in multiple crops in summer. PMID

  16. Maintaining the momentum: Key factors influencing acceptance of influenza vaccination among pregnant women following the H1N1 pandemic

    PubMed Central

    Halperin, Beth A; MacKinnon-Cameron, Donna; McNeil, Shelly; Kalil, Jennifer; Halperin, Scott A

    2015-01-01

    This survey study compared pre- and post-pandemic knowledge, attitudes, beliefs, and intended behaviors of pregnant women regarding influenza vaccination (seasonal and/or pandemic) during pregnancy in order to determine key factors influencing their decision to adhere to influenza vaccine recommendations. Only 36% of 662 pre-pandemic respondents knew that influenza was more severe in pregnant women, compared to 62% of the 159 post-pandemic respondents. Of the pre-pandemic respondents, 41% agreed or strongly agreed that that it was safer to wait until after the first 3 months to receive the seasonal influenza vaccine, whereas 23% of the post-pandemic cohort agreed or strongly agreed; 32% of pre-pandemic participants compared to 11% of post-pandemic respondents felt it was best to avoid all vaccines while pregnant. Despite 61% of the pre-pandemic cohort stating that they would have the vaccine while pregnant if their doctor recommended it and 54% citing their doctor/nurse as their primary source of vaccine information, only 20% said their doctor discussed influenza vaccination during their pregnancy, compared to 77% of the post-pandemic respondents who reported having this conversation. Women whose doctors discussed influenza vaccine during pregnancy had higher overall knowledge scores (P < 0.0001; P = 0.005) and were more likely to believe the vaccine is safe in all stages of pregnancy (P < 0.0001; P = 0.001) than those whose doctors did not discuss influenza vaccination. The 2009 H1N1 pandemic experience appeared to change attitudes and behaviours of health care providers and their pregnant patients toward influenza vaccination. PMID:25668670

  17. [Seasonal variation of cyanobacteria and its potential relationship with key environmental factors in Xiaojiang backwater area, Three Gorges Reservoir].

    PubMed

    Li, Zhe; Guo, Jing-song; Fang, Fang; Gao, Xu; Sheng, Jin-ping; Zhou, Hong; Long, Man

    2010-02-01

    Eutrophication and algal blooms occurred in the backwater areas of tributaries in Three Gorges Reservoir were the hot ecological issues in recent years. A one year field survey on cyanobacteria was put forward from May, 2007 to May, 2008 in Xiaojiang backwater area. 15 genera and 40 species of cyanophyta were detected. Mean value of cyanobacterial cell density was (23.50 +/- 10.30) x 10(5) cells x L(-1), i.e., 24.1% in the algal community, while the biomass was (768.70 +/- 287.40) microg x L(-1) which was 8.9% in the total biomass of algal community. Seasonal variation of cyanobacteria was apparent. Generally, cyanobacteria bloom occurred during late spring and early summer. Its abundance decreased after summer and reached the minimum level in winter. Anabaena, Aphanizomenon, Microcystis, Merismopedia and Phormidium were the common cynaobacterial genera. The cumulated cell density of these five genera of cyanobacteria above accounted up to 79.1% in the total cell density of cyanobacteria, while that of biomass accounted up to 77.6%. Spearman correlation analysis among the cell density, biomass as well as the key environmental factors indicated that utilization of inorganic nitrogen and phosphorus for anabolism was evident; however, nitrate would be the major nitrogen source for cyanobacteria. Moreover, increase of temperature and decrease of depth of euphotic zone had a significant effect on the abundance of cyanobacteria. According to co-analysis of hydrology and rainfall data in the whole year circle, it was found that nitrogen and phosphorus were input by the heavy rain and surface runoff with inorganic sediments, offering the enriched nutrients in water column. Meanwhile, turbidity increased by the inorganic suspended sediments decreased the depth of euphotic zone. The physiological advantage of cyanobacteria in low light and high turbidity environment might be the cause of cyanobacteria bloom in Xiaojiang backwater area. PMID:20391694

  18. Is health locus of control a 3-factor or a 2-factor construct?

    PubMed

    Talbot, F; Nouwen, A; Gauthier, J

    1996-09-01

    Although the Multidimensional Health Locus of Control (MHLC) scales are commonly used, uncertainty about their factorial validity still remains. In the present study, confirmatory factor analyses of a French-Canadian adaptation of the Multidimensional Health Locus of Control scales (MHLC) were conducted to compare in a non-clinical group of 224 adults two factor models. Multigroup analyses were also conducted using this group and a clinical group of 132 diabetics to assess the equivalence of the MHLC factor structure across these two groups. A 3-factor model postulating an internal, external, and chance dimension, and accounting for measurement errors provided the best fit to the data. Multigroup analyses failed to support the equivalence of the MHLC factor loadings across the non-clinical and clinical group. These findings suggest that comparisons of MHLC scores across such groups may be problematic. PMID:8877693

  19. Three-phase power factor controller with induced EMF sensing

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (Inventor)

    1984-01-01

    A power factor controller for an ac induction motor is provided which is of the type comprising thyristor switches connected in series with the motor, phase detectors for sensing the motor current and voltage and providing an output proportional to the phase difference between the motor voltage and current, and a control circuit, responsive to the output of the phase detector and to a power factor command signal, for controlling switching of the thyristor. The invention involves sensing the induced emf produced by the motor during the time interval when the thyristor is off and for producing a corresponding feedback signal for controlling switching of the thyristor. The sensed emf is also used to enhance soft starting of the motor.

  20. Three-phase power factor controller with induced EMF sensing

    NASA Astrophysics Data System (ADS)

    Nola, F. J.

    1984-09-01

    A power factor controller for an ac induction motor is provided which is of the type comprising thyristor switches connected in series with the motor, phase detectors for sensing the motor current and voltage and providing an output proportional to the phase difference between the motor voltage and current, and a control circuit, responsive to the output of the phase detector and to a power factor command signal, for controlling switching of the thyristor. The invention involves sensing the induced emf produced by the motor during the time interval when the thyristor is off and for producing a corresponding feedback signal for controlling switching of the thyristor. The sensed emf is also used to enhance soft starting of the motor.

  1. Methodology for Evaluating Security Controls Based on Key Performance Indicators and Stakeholder Mission

    SciTech Connect

    Sheldon, Frederick T; Abercrombie, Robert K; Mili, Ali

    2009-01-01

    Information security continues to evolve in response to disruptive changes with a persistent focus on information-centric controls and a healthy debate about balancing endpoint and network protection, with a goal of improved enterprise/business risk management. Economic uncertainty, intensively collaborative styles of work, virtualization, increased outsourcing and ongoing compliance pressures require careful consideration and adaptation. This paper proposes a Cyberspace Security Econometrics System (CSES) that provides a measure (i.e., a quantitative indication) of reliability, performance and/or safety of a system that accounts for the criticality of each requirement as a function of one or more stakeholders interests in that requirement. For a given stakeholder, CSES reflects the variance that may exist among the stakes she/he attaches to meeting each requirement. This paper introduces the basis, objectives and capabilities for the CSES including inputs/outputs as well as the structural and mathematical underpinnings.

  2. Synopsis of Evaluating Security Controls Based on Key Performance Indicators and Stakeholder Mission Value

    SciTech Connect

    Abercrombie, Robert K; Sheldon, Frederick T; Mili, Ali

    2008-01-01

    Information security continues to evolve in response to disruptive changes with a persistent focus on information-centric controls and a healthy debate about balancing endpoint and network protection, with the goal of improved enterprise and business risk management. Economic uncertainty, intensively collaborative work styles, virtualization, increased outsourcing and ongoing compliance pressures require careful consideration and adaptation of a balanced approach. The Cyberspace Security Econometrics System (CSES) provides a measure of reliability, security and safety of a system that accounts for the criticality of each requirement as a function of one or more stakeholders interests in that requirement. For a given stakeholder, CSES reflects the variance that may exist among the stakes one attaches to meeting each requirement. This paper summarizes the basis, objectives and capabilities for the CSES including inputs/outputs as well as the structural underpinnings.

  3. Neurotrophic factor control of satiety and body weight.

    PubMed

    Xu, Baoji; Xie, Xiangyang

    2016-05-01

    Energy balance - that is, the relationship between energy intake and energy expenditure - is regulated by a complex interplay of hormones, brain circuits and peripheral tissues. Leptin is an adipocyte-derived cytokine that suppresses appetite and increases energy expenditure. Ironically, obese individuals have high levels of plasma leptin and are resistant to leptin treatment. Neurotrophic factors, particularly ciliary neurotrophic factor (CNTF) and brain-derived neurotrophic factor (BDNF), are also important for the control of body weight. CNTF can overcome leptin resistance in order to reduce body weight, although CNTF and leptin activate similar signalling cascades. Mutations in the gene encoding BDNF lead to insatiable appetite and severe obesity. PMID:27052383

  4. Teleoperator hand controllers: A contextual human factors assessment

    SciTech Connect

    Draper, J.V.

    1994-05-01

    This document provides a human factors assessment of controllers for use with remotely controlled manipulators deployed to remove hazardous waste from underground storage tanks. The analysis concentrates on controller technique (i.e., the broad class of hand controller) and not on details of controller ergonomics. Examples of controller techniques include, for example, direct rate control, resolved unilateral position control, and direct bilateral position control. Using an existing concept, the Tank Waste Retrieval Manipulator System, as a reference, two basic types of manipulators may be identified for this application. A long reach, gross-positioning manipulator (LRM) may be used to position a smaller manipulator or an end-effector within a work site. For a Long Reach Manipulator, which will have an enormous motion range and be capable of high end-effector velocity, it will be safest and most efficient to use a resolved rate control system. A smaller, dexterous manipulator may be used to perform handling work within a relatively small work site, (i.e., to complete tasks requiring near-human dexterity). For a Dexterous Manipulator, which will have a smaller motion range than the LRM and be required to perform more difficult tasks, a resolved bilateral position control system will be safest and most efficient. However, during some waste recovery tasks it may be important to support the users by restricting movements to a single plane or axis. This can be done with a resolved bilateral position control system by (1) using the master controller force output to restrict controller inputs or (2) switching the controller to a multiaxis rate control mode and using the force output to provide a spring return to center functionality.

  5. Getting the Dimensions Right - Human Nutrition as Key for the Control of Regional Nitrogen Fluxes

    NASA Astrophysics Data System (ADS)

    Zessner, M.; Thaler, S.; Ruzicka, K.; Natho, S.

    2009-04-01

    to consider emissions to the air inside and outside the considered region (NH3 volatilisation from manure and NOX-emissions from burning processes as traffic) in addition to the direct losses to the water system (optimised fertiliser application). Basically, the key to improved nutrient management on national/catchment scale is the human nutrition. Nutrition of the population in accordance to health recommendations (50 % less meet consumption, contra balanced by an increasing amount of vegetarian food) would dramatically optimise the national nitrogen balance. Assuming the same basic nitrogen efficiency of agricultural as it is performed at present, this shift in production would lead to a dramatic relief in respect to environmental pressure. It would lead to a reduction of the needed nitrogen input (mineral fertiliser and import fooder) by about 40 % and a reduction of NH3 losses to the atmosphere of about 40 % as well. Assuming that the same reduction of meet production would be realised in neighbouring countries the deposition could be reduced by about 25 %. Finally, this would lead to reduced losses of nitrogen to the water system by about 35 %, which could be counter acted to some extent, if areas no longer needed for food production are used for cultivation of crops for renewable energy production.

  6. Among three different executive functions, general executive control ability is a key predictor of decision making under objective risk

    PubMed Central

    Schiebener, Johannes; Wegmann, Elisa; Gathmann, Bettina; Laier, Christian; Pawlikowski, Mirko; Brand, Matthias

    2014-01-01

    Executive functioning is supposed to have an important role in decision making under risk. Several studies reported that more advantageous decision-making behavior was accompanied by better performance in tests of executive functioning and that the decision-making process was accompanied by activations in prefrontal and subcortical brain regions associated with executive functioning. However, to what extent different components of executive functions contribute to decision making is still unclear. We tested direct and indirect effects of three executive functions on decision-making performance in a laboratory gambling task, the Game of Dice Task (GDT). Using Brand's model of decisions under risk (2006) we tested seven structural equation models with three latent variables that represent executive functions supposed to be involved in decision making. The latent variables were general control (represented by the general ability to exert attentional and behavioral self-control that is in accordance with task goals despite interfering information), concept formation (represented by categorization, rule detection, and set maintenance), and monitoring (represented by supervision of cognition and behavior). The seven models indicated that only the latent dimension general control had a direct effect on decision making under risk. Concept formation and monitoring only contributed in terms of indirect effects, when mediated by general control. Thus, several components of executive functioning seem to be involved in decision making under risk. However, general control functions seem to have a key role. They may be important for implementing the calculative and cognitively controlled processes involved in advantageous decision making under risk. PMID:25520690

  7. Key controls of surface carbonate system dynamics around the northwest European continental margin

    NASA Astrophysics Data System (ADS)

    Jiang, Z.; Hydes, D. J.; Hartman, S. E.; Hartman, M. C.

    2011-12-01

    Monthly sampling coupled to continuous underway observation from a ship-of-opportunity (Pride of Bilbao) provides new insights into the relative importance of processes controlling the seasonal to inter-annual variability of the carbonate system around the northwest European continental margin. Total alkalinity (TA) and total dissolved inorganic carbon (DIC) were determined alongside measurements of nutrients and continuous records of temperature, salinity, chlorophyll-fluorescence, and dissolved oxygen (DO). The northwest European continental margin is temperate latitude system with a strong seasonal cycle in biological productivity determined by light, nutrient supply, and stratification. Here we contrast findings in two areas: the shallow non stratified English Channel (depth ~50 m) and seasonally stratified oligotrophic waters of the central Bay of Biscay (depth >3000 m). In the Bay of Biscay, the seasonal variations of the carbonate system, nutrient, and DO were mainly controlled by the winter mixing and spring phytoplankton bloom. DIC and nutrients in the Bay increased from autumn and reached the annual maxima in later winter, they then decreased significantly during the spring bloom corresponding to the biological uptake. DIC fell during the spring bloom with a near Redfield ratio in relation to the nutrient uptake. In contrast, post bloom in summer, a continued decrease in DIC in the absence of measurable nitrate was possibly related to the nutrient supply from the turbulent mixing. pCO2 and pH showed a double peak in the annual cycles modulated by temperature which counterbalanced the influence of winter mixing and biological production. The inter-annual biogeochemical variability was closely related to the changes in winter mixed layer depth and the phytoplankton biomass. The Bay of Biscay acted as a sink for atmospheric CO2 in all seasons, with higher air-to-sea CO2 fluxes observed in cold winter and the productive spring season. In the more dynamic

  8. Evaluating Security Controls Based on Key Performance Indicators and Stakeholder Mission

    SciTech Connect

    Sheldon, Frederick T; Abercrombie, Robert K; Mili, Ali

    2008-01-01

    Good security metrics are required to make good decisions about how to design security countermeasures, to choose between alternative security architectures, and to improve security during operations. Therefore, in essence, measurement can be viewed as a decision aid. The lack of sound practical security metrics is severely hampering progress in the development of secure systems. The Cyberspace Security Econometrics System (CSES) offers the following advantages over traditional measurement systems: (1) CSES reflects the variances that exist amongst different stakeholders of the same system. Different stakeholders will typically attach different stakes to the same requirement or service (e.g., a service may be provided by an information technology system or process control system, etc.). (2) For a given stakeholder, CSES reflects the variance that may exist among the stakes she/he attaches to meeting each requirement. The same stakeholder may attach different stakes to satisfying different requirements within the overall system specification. (3) For a given compound specification (e.g., combination(s) of commercial off the shelf software and/or hardware), CSES reflects the variance that may exist amongst the levels of verification and validation (i.e., certification) performed on components of the specification. The certification activity may produce higher levels of assurance across different components of the specification than others. Consequently, this paper introduces the basis, objectives and capabilities for the CSES including inputs/outputs and the basic structural and mathematical underpinnings.

  9. Surface temperature: A key parameter to control the propanethiol plasma polymer chemistry

    SciTech Connect

    Thiry, Damien Aparicio, Francisco J.; Laha, Priya; Terryn, Herman; Snyders, Rony

    2014-09-01

    In this work, the influence of the substrate temperature (T{sub s}) on the chemical composition of propanethiol plasma polymers was investigated for a given set of plasma conditions. In a first study, a decrease in the atomic sulfur content (at. %S) with the deposition time (t{sub d}) was observed. This behavior is explained by the heating of the growing film during deposition process, limiting the incorporation of stable sulfur-based molecules produced in the plasma. Experiments carried out by controlling the substrate temperature support this hypothesis. On the other hand, an empirical law relating the T{sub s} and the at. %S was established. This allows for the formation of gradient layer presenting a heterogeneous chemical composition along the thickness, as determined by depth profile analysis combining X-ray photoelectron spectroscopy and C{sub 60} ion gun sputtering. The experimental data fit with the one predicted from our empiric description. The whole set of our results provide new insights in the relationship between the substrate temperature and the sulfur content in sulfur-based plasma polymers, essential for future developments.

  10. Morphology of crystals: Internal and external controlling factors

    NASA Astrophysics Data System (ADS)

    Liu, Xiang-Yang; Bennema, P.

    1994-01-01

    Internal and external factors that influence the morphology of crystals are studied based on an inhomogeneous cell model. After discussing the reason of the failure of two basic assumptions, the equivalent wetting condition and the proportionality condition, the influence of the ambient phase is explicitly taken into account in terms of the surface characteristic scaling factor C*l. In connection with the solid-fluid interfacial structure, which is commonly determined by the crystal and the ambient phase, C*l will provide the essential information concerning how the morphology of the crystals is affected. Within the framework of our formalism, internal and external factors controlling both equilibrium forms and growth forms of crystals are described separately. This offers a guideline for the modification of the habit of crystals. To describe the morphology of crystals, the periodic bond chain analysis can be used to determine the internal controlling factors, and the interfacial structure analysis, which is developed in this paper, can be used to determine the external controlling factors. These analyses are applied to predict the growth forms of n-paraffin crystals.

  11. Tartaric acid in red wine as one of the key factors to induce superconductivity in FeTe0.8S0.2

    NASA Astrophysics Data System (ADS)

    Deguchi, Keita; Okuda, Tohru; Hara, Hiroshi; Demura, Satoshi; Watanabe, Tohru; Okazaki, Hiroyuki; Fujioka, Masaya; Denholme, Saleem James; Ozaki, Toshinori; Yamaguchi, Takahide; Takeya, Hiroyuki; Saito, Fumie; Hisamoto, Masashi; Takano, Yoshihiko

    2013-04-01

    We investigated the key factor of superconductivity in FeTe1-xSx induced by alcoholic beverages. To understand the reason why red wine shows larger shielding volume fraction than the other alcoholic beverages, the red wine dependence of superconductivity was performed. All the samples heated in red wine made from different grapes shows large shielding volume fraction compared with the samples heated in water and other alcoholic beverages. The shielding volume fraction of the red wine samples is proportional to the concentration of tartaric acid. We found that tartaric acid is one of the key factors to induce superconductivity in FeTe1-xSx.

  12. Physiology and Endocrinology Symposium. Factors controlling puberty in beef heifers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Physiology and Endocrinology Symposium on “Factors controlling puberty in beef heifers” was held at the joint annual meeting of the American Dairy Science Association and the American Society of Animal Science in New Orleans, Louisiana, USA, July 10 to 14, 2011. The objective of the symposium w...

  13. Power factor control system for AC induction motors

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (Inventor)

    1977-01-01

    A power factor control system for use with ac induction motors was designed which samples lines voltage and current through the motor and decreases power input to the motor proportional to the detected phase displacement between current and voltage. This system provides, less power to the motor, as it is less loaded.

  14. Intrapituitary mechanisms underlying the control of fertility: key players in seasonal breeding.

    PubMed

    Tortonese, D J

    2016-07-01

    gonadotropes and lactotropes could also underlie an interaction between the gonadotropic and prolactin axes in the opposite direction. In support of this alternative, a series of studies have demonstrated that GnRH stimulates prolactin secretion in sheep through a mechanism that does not involve the mediatory actions of LH or FSH and that this stimulatory effect of GnRH on the prolactin axis is seasonally regulated. Collectively, these findings highlight the importance of intercellular communications within the pituitary in the control of gonadotropin and prolactin secretion during the annual reproductive cycle in seasonal breeders. PMID:27345316

  15. Topography and crop management are key factors for the development of american leaf spot epidemics on coffee in costa rica.

    PubMed

    Avelino, Jacques; Cabut, Sandrine; Barboza, Bernardo; Barquero, Miguel; Alfaro, Ronny; Esquivel, César; Durand, Jean-François; Cilas, Christian

    2007-12-01

    ABSTRACT We monitored the development of American leaf spot of coffee, a disease caused by the gemmiferous fungus Mycena citricolor, in 57 plots in Costa Rica for 1 or 2 years in order to gain a clearer understanding of conditions conducive to the disease and improve its control. During the investigation, characteristics of the coffee trees, crop management, and the environment were recorded. For the analyses, we used partial least-squares regression via the spline functions (PLSS), which is a nonlinear extension to partial least-squares regression (PLS). The fungus developed well in areas located between approximately 1,100 and 1,550 m above sea level. Slopes were conducive to its development, but eastern-facing slopes were less affected than the others, probably because they were more exposed to sunlight, especially in the rainy season. The distance between planting rows, the shade percentage, coffee tree height, the type of shade, and the pruning system explained disease intensity due to their effects on coffee tree shading and, possibly, on the humidity conditions in the plot. Forest trees and fruit trees intercropped with coffee provided particularly propitious conditions. Apparently, fertilization was unfavorable for the disease, probably due to dilution phenomena associated with faster coffee tree growth. Finally, series of wet spells interspersed with dry spells, which were frequent in the middle of the rainy season, were critical for the disease, probably because they affected the production and release of gemmae and their viability. These results could be used to draw up a map of epidemic risks taking topographical factors into account. To reduce those risks and improve chemical control, our results suggested that farmers should space planting rows further apart, maintain light shading in the plantation, and prune their coffee trees. PMID:18943713

  16. ‘Tempos’ management in primary care: a key factor for classifying adverse events, and improving quality and safety

    PubMed Central

    Brami, J

    2012-01-01

    Background The role of time management in safe and efficient medicine is important but poorly incorporated into the taxonomies of error in primary care. This paper addresses the lack of time management, presenting a framework integrating five time scales termed ‘Tempos’ requiring parallel processing by GPs: the disease's tempo (unexpected rapid evolutions, slow reaction to treatment); the office's tempo (day-to-day agenda and interruptions); the patient's tempo (time to express symptoms, compliance, emotion); the system's tempo (time for appointments, exams, and feedback); and the time to access to knowledge. The art of medicine is to control all of these tempos in parallel and simultaneously. Method Two qualified physicians reviewed a sample of 1046 malpractice claims from one liability insurer to determine whether a medical injury had occurred and, if so, whether it was due to one or more tempo-related problems. 623 of these reports were analysed in greater detail to identify the prevalence and characteristics of claims and related time management errors. Results The percentages of contributing factors were as follows: disease tempo, 37.9%; office tempo, 13.2%; patient tempo, 13.8%; out-of-office coordination tempo, 22.6%; and GP's access to knowledge tempo, 33.2%. Conclusion Although not conceptualised in most error taxonomies, the disease and patient tempos are cornerstones in risk management in primary care. Traditional taxonomies describe events from an analytical perspective of care at the system level and offer opportunities to improve organisation, process, and evidence-based medicine. The suggested classification describes events in terms of (unsafe) dynamic control of parallel constraints from the carer's perspective, namely the GP, and offers improvement on how to self manage and coordinate different contradictory tempos and day-to-day activities. Further work is needed to test the validity and usefulness of this approach. PMID:22927486

  17. Key design factors affecting microbial community composition and pathogenic organism removal in horizontal subsurface flow constructed wetlands.

    PubMed

    Morató, Jordi; Codony, Francesc; Sánchez, Olga; Pérez, Leonardo Martín; García, Joan; Mas, Jordi

    2014-05-15

    Constructed wetlands constitute an interesting option for wastewater reuse since high concentrations of contaminants and pathogenic microorganisms can be removed with these natural treatment systems. In this work, the role of key design factors which could affect microbial removal and wetland performance, such as granular media, water depth and season effect was evaluated in a pilot system consisting of eight parallel horizontal subsurface flow (HSSF) constructed wetlands treating urban wastewater from Les Franqueses del Vallès (Barcelona, Spain). Gravel biofilm as well as influent and effluent water samples of these systems were taken in order to detect the presence of bacterial indicators such as total coliforms (TC), Escherichia coli, fecal enterococci (FE), Clostridium perfringens, and other microbial groups such as Pseudomonas and Aeromonas. The overall microbial inactivation ratio ranged between 1.4 and 2.9 log-units for heterotrophic plate counts (HPC), from 1.2 to 2.2 log units for total coliforms (TC) and from 1.4 to 2.3 log units for E. coli. The presence of fine granulometry strongly influenced the removal of all the bacterial groups analyzed. This effect was significant for TC (p=0.009), E. coli (p=0.004), and FE (p=0.012). Shallow HSSF constructed wetlands were more effective for removing Clostridium spores (p=0.039), and were also more efficient for removing TC (p=0.011) and E. coli (p=0.013) when fine granulometry was used. On the other hand, changes in the total bacterial community from gravel biofilm were examined by using denaturing gradient gel electrophoresis (DGGE) and sequencing of polymerase chain reaction (PCR)-amplified fragments of the 16S rRNA gene recovered from DGGE bands. Cluster analysis of the DGGE banding pattern from the different wetlands showed that microbial assemblages separated according to water depth, and sequences of different phylogenetic groups, such as Alpha, Beta and Delta-Proteobacteria, Nitrospirae, Bacteroidetes

  18. Low cost, small form factor, and integration as the key features for the optical component industry takeoff

    NASA Astrophysics Data System (ADS)

    Schiattone, Francesco; Bonino, Stefano; Gobbi, Luigi; Groppi, Angelamaria; Marazzi, Marco; Musio, Maurizio

    2003-04-01

    In the past the optical component market has been mainly driven by performances. Today, as the number of competitors has drastically increased, the system integrators have a wide range of possible suppliers and solutions giving them the possibility to be more focused on cost and also on footprint reduction. So, if performances are still essential, low cost and Small Form Factor issues are becoming more and more crucial in selecting components. Another evolution in the market is the current request of the optical system companies to simplify the supply chain in order to reduce the assembling and testing steps at system level. This corresponds to a growing demand in providing subassemblies, modules or hybrid integrated components: that means also Integration will be an issue in which all the optical component companies will compete to gain market shares. As we can see looking several examples offered by electronic market, to combine low cost and SFF is a very challenging task but Integration can help in achieving both features. In this work we present how these issues could be approached giving examples of some advanced solutions applied to LiNbO3 modulators. In particular we describe the progress made on automation, new materials and low cost fabrication methods for the parts. We also introduce an approach in integrating optical and electrical functionality on LiNbO3 modulators including RF driver, bias control loop, attenuator and photodiode integrated in a single device.

  19. Response Surfaces for Key Controlled Variables in a Hybrid Solid Oxide Fuel Cell/Gas Turbine System

    SciTech Connect

    Rosen, William G; Banta, Larry; Gorrell, Megan; Restrepo, Bernardo; Tucker, David

    2012-07-01

    Hybrid generation systems have been extensively modeled as a first step toward the development of automatic controls for the system. In most cases, it is impossible to validate mathematical models against real hardware because only a handful of hardware systems exist in the world. Data taken from the existing hardware has demonstrated significant nonlinearity, complex coupling between controlled variables, and sometimes non-intuitive behavior. This work exploits the capability of the HyPer hardware test bed at the National Energy Technology Laboratory (NETL) to generate data from a real recuperated gas turbine coupled with hardware simulations of a fuel cell cathode and appropriate ancillary equipment. Prior work has characterized the system only over a limited range of its operating envelope, due to the inability to manipulate multiple control inputs simultaneously. The work presented here fills the gaps using data from a 34 factorial experiment to generate quasi-continuous response surfaces describing the operating state space of the HyPer system. Polynomial correlation functions have been fitted to the data with excellent agreement. Relationships between the control inputs and critical state variables such as cathode mass flow, cathode temperature, turbine inlet and exhaust temperatures and other key system parameters are presented.

  20. Non-metastatic 2 (NME2)-mediated suppression of lung cancer metastasis involves transcriptional regulation of key cell adhesion factor vinculin

    PubMed Central

    Thakur, Ram Krishna; Yadav, Vinod Kumar; Kumar, Akinchan; Singh, Ankita; Pal, Krishnendu; Hoeppner, Luke; Saha, Dhurjhoti; Purohit, Gunjan; Basundra, Richa; Kar, Anirban; Halder, Rashi; Kumar, Pankaj; Baral, Aradhita; Kumar, MJ Mahesh; Baldi, Alfonso; Vincenzi, Bruno; Lorenzon, Laura; Banerjee, Rajkumar; Kumar, Praveen; Shridhar, Viji; Mukhopadhyay, Debabrata; Chowdhury, Shantanu

    2014-01-01

    Tumor metastasis refers to spread of a tumor from site of its origin to distant organs and causes majority of cancer deaths. Although >30 metastasis suppressor genes (MSGs) that negatively regulate metastasis have been identified so far, two issues are poorly understood: first, which MSGs oppose metastasis in a tumor type, and second, which molecular function of MSG controls metastasis. Herein, integrative analyses of tumor-transcriptomes (n = 382), survival data (n = 530) and lymph node metastases (n = 100) in lung cancer patients identified non-metastatic 2 (NME2) as a key MSG from a pool of >30 metastasis suppressors. Subsequently, we generated a promoter-wide binding map for NME2 using chromatin immunoprecipitation with promoter microarrays (ChIP-chip), and transcriptome profiling. We discovered novel targets of NME2 which are involved in focal adhesion signaling. Importantly, we detected binding of NME2 in promoter of focal adhesion factor, vinculin. Reduced expression of NME2 led to enhanced transcription of vinculin. In comparison, NME1, a close homolog of NME2, did not bind to vinculin promoter nor regulate its expression. In line, enhanced metastasis of NME2-depleted lung cancer cells was found in zebrafish and nude mice tumor models. The metastatic potential of NME2-depleted cells was remarkably diminished upon selective RNA-i-mediated silencing of vinculin. Together, we demonstrate that reduced NME2 levels lead to transcriptional de-repression of vinculin and regulate lung cancer metastasis. PMID:25249619

  1. Student-University Relationships and Reputation: A Study of the Links between Key Factors Fostering Students' Supportive Behavioral Intentions towards Their University

    ERIC Educational Resources Information Center

    Sung, Minjung; Yang, Sung-Un

    2009-01-01

    Focusing on academic institutions in higher education as the research context, this study examined the relations of key factors affecting students' supportive behavioral intentions toward the university (e.g., giving gifts as alumni, continuing education, and giving referrals regarding the university). Based on the literature from various…

  2. Key Source Habitats and Potential Dispersal of Triatoma infestans Populations in Northwestern Argentina: Implications for Vector Control

    PubMed Central

    Gürtler, Ricardo E.; Cecere, María C.; Fernández, María del Pilar; Vazquez-Prokopec, Gonzalo M.; Ceballos, Leonardo A.; Gurevitz, Juan M.; Kitron, Uriel; Cohen, Joel E.

    2014-01-01

    Background Triatoma infestans —the principal vector of the infection that causes Chagas disease— defies elimination efforts in the Gran Chaco region. This study identifies the types of human-made or -used structures that are key sources of these bugs in the initial stages of house reinfestation after an insecticide spraying campaign. Methodology and Principal Findings We measured demographic and blood-feeding parameters at two geographic scales in 11 rural communities in Figueroa, northwest Argentina. Of 1,297 sites searched in spring, 279 (21.5%) were infested. Bug abundance per site and female fecundity differed significantly among habitat types (ecotopes) and were highly aggregated. Domiciles (human sleeping quarters) had maximum infestation prevalence (38.7%), human-feeding bugs and total egg production, with submaximal values for other demographic and blood-feeding attributes. Taken collectively peridomestic sites were three times more often infested than domiciles. Chicken coops had greater bug abundance, blood-feeding rates, engorgement status, and female fecundity than pig and goat corrals. The host-feeding patterns were spatially structured yet there was strong evidence of active dispersal of late-stage bugs between ecotopes. Two flight indices predicted that female fliers were more likely to originate from kitchens and domiciles, rejecting our initial hypothesis that goat and pig corrals would dominate. Conclusions and Significance Chicken coops and domiciles were key source habitats fueling rapid house reinfestation. Focusing control efforts on ecotopes with human-fed bugs (domiciles, storerooms, goat corrals) would neither eliminate the substantial contributions to bug population growth from kitchens, chicken coops, and pig corrals nor stop dispersal of adult female bugs from kitchens. Rather, comprehensive control of the linked network of ecotopes is required to prevent feeding on humans, bug population growth, and bug dispersal simultaneously. Our

  3. Risk Factors for Pancreatic Cancer: Case-Control Study

    PubMed Central

    Hassan, Manal M.; Bondy, Melissa L.; Wolff, Robert A.; Abbruzzese, James L.; Vauthey, Jean-Nicolas; Pisters, Peter W.; Evans, Douglas B.; Khan, Rabia; Chou, Ta-Hsu; Lenzi, Renato; Jiao, Li; Li, Donghui

    2008-01-01

    OBJECTIVES Although cigarette smoking is the most well-established environmental risk factor for pancreatic cancer, the interaction between smoking and other risk factors has not been assessed. We evaluated the independent effects of multiple risk factors for pancreatic cancer and determined whether the magnitude of cigarette smoking was modified by other risk factors in men and women. METHODS We conducted a hospital-based case-control study involving 808 patients with pathologically diagnosed pancreatic cancer and 808 healthy frequency-matched controls. Information on risk factors was collected by personal interview, and unconditional logistic regression was used to determine adjusted odds ratios (AORs) by the maximum-likelihood method. RESULTS Cigarette smoking, family history of pancreatic cancer, heavy alcohol consumption (>60 mL ethanol/day), diabetes mellitus, and history of pancreatitis were significant risk factors for pancreatic cancer. We found synergistic interactions between cigarette smoking and family history of pancreatic cancer (AOR 12.8, 95% confidence interval [CI] 1.6–108.9) and diabetes mellitus (AOR 9.3, 95% CI 2.0–44.1) in women, according to an additive model. Approximately 23%, 9%, 3%, and 5% of pancreatic cancer cases in this study were related to cigarette smoking, diabetes mellitus, heavy alcohol consumption, and family history of pancreatic cancer, respectively. CONCLUSIONS The significant synergy between these risk factors suggests a common pathway for carcinogenesis of the pancreas. Determining the underlying mechanisms for such synergies may lead to the development of pancreatic cancer prevention strategies for high-risk individuals. PMID:17764494

  4. Using human factors engineering to improve the effectiveness of infection prevention and control.

    PubMed

    Anderson, Judith; Gosbee, Laura Lin; Bessesen, Mary; Williams, Linda

    2010-08-01

    Human factors engineering is a discipline that studies the capabilities and limitations of humans and the design of devices and systems for improved performance. The principles of human factors engineering can be applied to infection prevention and control to study the interaction between the healthcare worker and the system that he or she is working with, including the use of devices, the built environment, and the demands and complexities of patient care. Some key challenges in infection prevention, such as delayed feedback to healthcare workers, high cognitive workload, and poor ergonomic design, are explained, as is how human factors engineering can be used for improvement and increased compliance with practices to prevent hospital-acquired infections. PMID:20647784

  5. Vascular endothelial growth factor-D is a key molecule that enhances lymphatic metastasis of soft tissue sarcomas

    SciTech Connect

    Yanagawa, Takashi; Shinozaki, Tetsuya; Watanabe, Hideomi; Saito, Kenichi; Raz, Avraham; Takagishi, Kenji

    2012-04-15

    Studies on lymph node metastasis of soft tissue sarcomas are insufficient because of its rarity. In this study, we examined the expressions of vascular endothelial growth factor (VEGF)-C and VEGF-D in soft tissue sarcomas metastasized to lymph nodes. In addition, the effects of the two molecules on the barrier function of a lymphatic endothelial cell monolayer against sarcoma cells were analyzed. We examined 7 patients who had soft tissue sarcomas with lymph node metastases and who had undergone neither chemotherapy nor radiotherapy before lymphadenectomy. Immunohistochemistry revealed that 2 of 7 sarcomas that metastasized to lymph nodes expressed VEGF-C both in primary and metastatic lesions. On the other hand, VEGF-D expression was detected in 4 of 7 primary and 7 of 7 metastatic lesions, respectively. Interestingly, 3 cases that showed no VEGF-D expression at primary sites expressed VEGF-D in metastatic lesions. Recombinant VEGF-C at 10{sup -8} and VEGF-D at 10{sup -7}and 10{sup -8} g/ml significantly increased the random motility of lymphatic endothelial cells compared with controls. VEGF-D significantly increased the migration of sarcoma cells through lymphatic endothelial monolayers. The fact that VEGF-D induced the migration of fibrosarcomas through the lymphatic endothelial monolayer is the probable reason for the strong relationship between VEGF-D expression and lymph node metastasis in soft tissue sarcomas. The important propensities of this molecule for the increase of lymph node metastases are not only lymphangiogenesis but also down-regulation of the barrier function of lymphatic endothelial monolayers, which facilitates sarcoma cells entering the lymphatic circulation.

  6. The Sigma Factor AlgU Plays a Key Role in Formation of Robust Biofilms by Nonmucoid Pseudomonas aeruginosa▿

    PubMed Central

    Bazire, Alexis; Shioya, Kouki; Soum-Soutéra, Emmanuelle; Bouffartigues, Emeline; Ryder, Cynthia; Guentas-Dombrowsky, Linda; Hémery, Gaëlle; Linossier, Isabelle; Chevalier, Sylvie; Wozniak, Daniel J.; Lesouhaitier, Olivier; Dufour, Alain

    2010-01-01

    The extracytoplasmic function sigma factor AlgU of Pseudomonas aeruginosa is responsible for alginate overproduction, leading to mucoidy and chronic infections of cystic fibrosis patients. We investigated here the role of AlgU in the formation of nonmucoid biofilms. The algU mutant of P. aeruginosa PAO1 (PAOU) showed a dramatic impairment in biofilm formation under dynamic conditions. PAOU was defective both in cell attachment to glass and in development of robust, shear-resistant biofilms. This was explained by an impaired production of extracellular matrix, specifically of the exopolysaccharide Psl, as revealed by microscopy and enzyme-linked immunosorbent assay. Complementing the algU mutation with a plasmid-borne algU gene restored wild-type phenotypes. Compared with that in PAO1, expression of the psl operon was reduced in the PAOU strain, and the biofilm formation ability of this strain was partially restored by inducing the transcription of the psl operon. Furthermore, expression of the lectin-encoding lecA and lecB genes was reduced in the PAOU strain. In agreement with the requirement of LecB for type IV pilus biogenesis, PAOU displayed impaired twitching motility. Collectively, these genetic downregulation events explain the biofilm formation defect of the PAOU mutant. Promoter mapping indicated that AlgU is probably not directly responsible for transcription of the psl operon and the lec genes, but AlgU is involved in the expression of the ppyR gene, whose product was reported to positively control psl expression. Expressing the ppyR gene in PAOU partially restored the formation of robust biofilms. PMID:20348252

  7. Human factors in aviation: Terminal control area boundary conflicts

    NASA Technical Reports Server (NTRS)

    Monan, William P.

    1989-01-01

    Air-to-air conflicts in the vicinity of Terminal Control Area (TCA) boundaries were studied to obtain a better understanding of the causal dynamics of these events with particular focus on human factor issues. The study dataset consisted of 381 Instrument Flight Rules/Visual Flight Rules (IFR/VFR) traffic conflicts in airspace layers above TCA ceiling and below TCA floors; 213 reports of incursions in TCA terminal airspace by VFR aircraft, of which 123 resulted in conflicts; and an additional set of reports describing problems with Air Traffic Control (ATC) services in and around TCAs. Results and conclusions are detailed.

  8. Characteristics of Master Teachers: Personality Factors, Self-Concept, Locus of Control, and Pupil Control Ideology.

    ERIC Educational Resources Information Center

    Sparks, Rozanne; Lipka, Richard P.

    1992-01-01

    A study of differences among 29 secondary school teachers rated by 501 secondary school students, other teachers, and administrators as master teachers or rated as not-so-masterful found no significant differences in teacher locus of control, pupil control ideology, and self-concept but did find differences in personality factors. (SLD)

  9. Controlling for Gene Expression Changes in Transcription Factor Protein Networks*

    PubMed Central

    Banks, Charles A. S.; Lee, Zachary T.; Boanca, Gina; Lakshminarasimhan, Mahadevan; Groppe, Brad D.; Wen, Zhihui; Hattem, Gaye L.; Seidel, Chris W.; Florens, Laurence; Washburn, Michael P.

    2014-01-01

    The development of affinity purification technologies combined with mass spectrometric analysis of purified protein mixtures has been used both to identify new protein–protein interactions and to define the subunit composition of protein complexes. Transcription factor protein interactions, however, have not been systematically analyzed using these approaches. Here, we investigated whether ectopic expression of an affinity tagged transcription factor as bait in affinity purification mass spectrometry experiments perturbs gene expression in cells, resulting in the false positive identification of bait-associated proteins when typical experimental controls are used. Using quantitative proteomics and RNA sequencing, we determined that the increase in the abundance of a set of proteins caused by overexpression of the transcription factor RelA is not sufficient for these proteins to then co-purify non-specifically and be misidentified as bait-associated proteins. Therefore, typical controls should be sufficient, and a number of different baits can be compared with a common set of controls. This is of practical interest when identifying bait interactors from a large number of different baits. As expected, we found several known RelA interactors enriched in our RelA purifications (NFκB1, NFκB2, Rel, RelB, IκBα, IκBβ, and IκBε). We also found several proteins not previously described in association with RelA, including the small mitochondrial chaperone Tim13. Using a variety of biochemical approaches, we further investigated the nature of the association between Tim13 and NFκB family transcription factors. This work therefore provides a conceptual and experimental framework for analyzing transcription factor protein interactions. PMID:24722732

  10. Characterisation of genes encoding key enzymes involved in sugar metabolism of apple fruit in controlled atmosphere storage.

    PubMed

    Zhu, Zhu; Liu, Ruiling; Li, Boqiang; Tian, Shiping

    2013-12-15

    Sugars are essential contributors to fruit flavour. Controlled atmosphere (CA) storage has been proved to be beneficial for maintaining harvested fruit quality. To explore regulatory mechanism of sugar metabolism in fruit stored in CA condition, we cloned several genes, encoding key enzymes, involved in sugar metabolism in apple fruit, and analyzed sugar contents, along with gene expression and enzyme activities in fruits stored in air and CA. The results indicated that CA could maintain higher contents of sugars, including sucrose, fructose and glucose. Expression levels of key genes, such as sucrose synthase (SS), sucrose phosphate synthase (SPS), fructokinase (FK) and hexokinase (HK), were shown to be correlated with the corresponding enzyme activities. We found that activities of neutral invertase (NI), vacuolar invertase (VI), FK and HK were inhibited, but SPS activity was promoted in apple fruit stored in CA, suggesting that CA storage could enhance sucrose synthesis and delay hydrolysis of sucrose and hexose. These findings provided molecular evidence to explain why higher sugar levels in harvested fruit are maintained under CA storage. PMID:23993488

  11. The key factor limiting plant growth in cold and humid alpine areas also plays a dominant role in plant carbon isotope discrimination

    PubMed Central

    Xu, Meng; Wang, Guoan; Li, Xiaoliang; Cai, Xiaobu; Li, Xiaolin; Christie, Peter; Zhang, Junling

    2015-01-01

    Many environmental factors affect carbon isotope discrimination in plants, yet the predominant factor influencing this process is generally assumed to be the key growth-limiting factor. However, to our knowledge this hypothesis has not been confirmed. We therefore determined the carbon isotope composition (δ13C) of plants growing in two cold and humid mountain regions where temperature is considered to be the key growth-limiting factor. Mean annual temperature (MAT) showed a significant impact on variation in carbon isotope discrimination value (Δ) irrespective of study area or plant functional type with either partial correlation or regression analysis, but the correlation between Δ and soil water content (SWC) was usually not significant. In multiple stepwise regression analysis, MAT was either the first or the only variable selected into the prediction model of Δ against MAT and SWC, indicating that the effect of temperature on carbon isotope discrimination was predominant. The results therefore provide evidence that the key growth-limiting factor is also crucial for plant carbon isotope discrimination. Changes in leaf morphology, water viscosity and carboxylation efficiency with temperature may be responsible for the observed positive correlation between Δ and temperature. PMID:26579188

  12. Decreased levels of proapoptotic factors and increased key regulators of mitochondrial biogenesis constitute new potential beneficial features of long-lived growth hormone receptor gene-disrupted mice.

    PubMed

    Gesing, Adam; Masternak, Michal M; Lewinski, Andrzej; Karbownik-Lewinska, Malgorzata; Kopchick, John J; Bartke, Andrzej

    2013-06-01

    Decreased somatotrophic signaling is among the most important mechanisms associated with extended longevity. Mice homozygous for the targeted disruption of the growth hormone (GH) receptor gene (GH receptor knockout; GHRKO) are obese and dwarf, are characterized by a reduced weight and body size, undetectable levels of GH receptor, high concentration of serum GH, and greatly reduced plasma levels of insulin and insulin-like growth factor-I, and are remarkably long lived. Recent results suggest new features of GHRKO mice that may positively affect longevity-decreased levels of proapoptotic factors and increased levels of key regulators of mitochondrial biogenesis. The alterations in levels of the proapoptotic factors and key regulators of mitochondrial biogenesis were not further improved by two other potential life-extending interventions-calorie restriction and visceral fat removal. This may attribute the primary role to GH resistance in the regulation of apoptosis and mitochondrial biogenesis in GHRKO mice in terms of increased life span. PMID:23197187

  13. OARSI Clinical Trials Recommendations: Key analytic considerations in design, analysis, and reporting of randomized controlled trials in osteoarthritis.

    PubMed

    Losina, E; Ranstam, J; Collins, J E; Schnitzer, T J; Katz, J N

    2015-05-01

    To highlight methodologic challenges pertinent to design, analysis, and reporting of results of randomized clinical trials in OA and offer practical suggestions to overcome these challenges. The topics covered in this paper include subject selection, randomization, approaches to handling missing data, subgroup analysis, sample size, and issues related to changing design mid-way through the study. Special attention is given to standardizing the reporting of results and economic analyses. Key findings include the importance of blinding and concealment, the distinction between superiority and non-inferiority trials, the need to minimize missing data, and appropriate analysis and interpretation of subgroup effects. Investigators may use the findings and recommendations advanced in this paper to guide design and conduct of randomized controlled trials of interventions for osteoarthritis. PMID:25952341

  14. A Phylogenetically Conserved Group of Nuclear Factor-Y Transcription Factors Interact to Control Nodulation in Legumes1[OPEN

    PubMed Central

    Laloum, Tom; Lepage, Agnès; Ariel, Federico; Frances, Lisa; Gamas, Pascal; de Carvalho-Niebel, Fernanda

    2015-01-01

    The endosymbiotic association between legumes and soil bacteria called rhizobia leads to the formation of a new root-derived organ called the nodule in which differentiated bacteria convert atmospheric nitrogen into a form that can be assimilated by the host plant. Successful root infection by rhizobia and nodule organogenesis require the activation of symbiotic genes that are controlled by a set of transcription factors (TFs). We recently identified Medicago truncatula nuclear factor-YA1 (MtNF-YA1) and MtNF-YA2 as two M. truncatula TFs playing a central role during key steps of the Sinorhizobium meliloti-M. truncatula symbiotic interaction. NF-YA TFs interact with NF-YB and NF-YC subunits to regulate target genes containing the CCAAT box consensus sequence. In this study, using a yeast two-hybrid screen approach, we identified the NF-YB and NF-YC subunits able to interact with MtNF-YA1 and MtNF-YA2. In yeast (Saccharomyces cerevisiae) and in planta, we further demonstrated by both coimmunoprecipitation and bimolecular fluorescence complementation that these NF-YA, -B, and -C subunits interact and form a stable NF-Y heterotrimeric complex. Reverse genetic and chromatin immunoprecipitation-PCR approaches revealed the importance of these newly identified NF-YB and NF-YC subunits for rhizobial symbiosis and binding to the promoter of MtERN1 (for Ethylene Responsive factor required for Nodulation), a direct target gene of MtNF-YA1 and MtNF-YA2. Finally, we verified that a similar trimer is formed in planta by the common bean (Phaseolus vulgaris) NF-Y subunits, revealing the existence of evolutionary conserved NF-Y protein complexes to control nodulation in leguminous plants. This sheds light on the process whereby an ancient heterotrimeric TF mainly controlling cell division in animals has acquired specialized functions in plants. PMID:26432878

  15. Arginase 1 Regulation of Nitric Oxide Production Is Key to Survival of Trophic Factor-Deprived Motor Neurons

    PubMed Central

    Estévez, Alvaro G.; Sahawneh, Mary Anne; Lange, Philipp S.; Bae, Narae; Egea, Mariela; Ratan, Rajiv R.

    2008-01-01

    When deprived of trophic factors, the majority of cultured motor neurons undergo nitric oxide-dependent apoptosis. However, for reasons that have remained unclear, 30–50% of the motor neurons survive for several days without trophic factors. Here we hypothesize that the resistance of this motor neuron subpopulation to trophic factor deprivation can be attributed to diminished nitric oxide production resulting from the activity of the arginine-degrading enzyme arginase. When incubated with nor-NG-hydroxy-nor-l-arginine (NOHA), the normally resistant trophic factor-deprived motor neurons showed a drop in survival rates, whereas trophic factor-treated neurons did not. NOHA-induced motor neuron death was inhibited by blocking nitric oxide synthesis and the scavenging of superoxide and peroxynitrite, suggesting that peroxynitrite mediates NOHA toxicity. When we transfected arginase 1 into motor neurons to see whether it alone could abrogate trophic factor deprivation-induced death, we found that its forced expression did indeed do so. The protection afforded by arginase 1 expression is reversed when cells are incubated with NOHA or with low concentrations of nitric oxide. These results reveal that arginase acts as a central regulator of trophic factor-deprived motor neuron survival by suppressing nitric oxide production and the consequent peroxynitrite toxicity. They also suggest that the resistance of motor neuron subpopulations to trophic factor deprivation may result from increased arginase activity. PMID:16914676

  16. A human factors approach to range scheduling for satellite control

    NASA Technical Reports Server (NTRS)

    Wright, Cameron H. G.; Aitken, Donald J.

    1991-01-01

    Range scheduling for satellite control presents a classical problem: supervisory control of a large-scale dynamic system, with unwieldy amounts of interrelated data used as inputs to the decision process. Increased automation of the task, with the appropriate human-computer interface, is highly desirable. The development and user evaluation of a semi-automated network range scheduling system is described. The system incorporates a synergistic human-computer interface consisting of a large screen color display, voice input/output, a 'sonic pen' pointing device, a touchscreen color CRT, and a standard keyboard. From a human factors standpoint, this development represents the first major improvement in almost 30 years to the satellite control network scheduling task.

  17. The environmental risk factors in multiple sclerosis susceptibility: A case-control study

    PubMed Central

    Shaygannejad, Vahid; Rezaie, Nooshin; Paknahad, Zamzam; Ashtari, Freshteh; Maghzi, Helia

    2016-01-01

    Background: Multiple sclerosis (MS) is a demyelinating and degenerating disease which involves central nervous system. Environmental risk factors have a key role in MS susceptibility. Here we aim to investigate different risk factors effect on MS susceptibility in a large population of MS patients in Isfahan, Iran. Materials and Methods: This study is a cross-sectional hospital-based study, which was conducted on a large group of MS patients registered in Kashani hospital and a control group from normal healthy population. Demographic data, age at onset of the disease, history of viral infections, vaccination, history of trauma to head, recent stressful events, alimentation, familial history, method of delivery (caesarean section, normal vaginal delivery), disability score and history of smoking were gathered using a designed questionnaire. Results: Totally 536 MS patient with the mean age of 34.37 ± 9.22 and 399 individuals from healthy population with the mean age of 32.53 ± 9.91 were recruited. Significant difference in history of measles infection (control = 15.5%, case = 22.4%, P = 0.009), consumption of dairy products (case = 56.6%, control = 67.5%, P = 0.01) and major stressful life events (case = 62.2%, control = 52.7%, P < 0.05) between these two groups were demonstrated. Conclusion: A significant relation between stress, history of infection and milk consumption was reached that highlights the importance of environmental risk factors in MS pathogenesis. PMID:27376037

  18. Representing Microbial Dormancy in Soil Decomposition Models Improves Model Performance and Reveals Key Ecosystem Controls on Microbial Activity

    NASA Astrophysics Data System (ADS)

    He, Y.; Yang, J.; Zhuang, Q.; Wang, G.; Liu, Y.

    2014-12-01

    Climate feedbacks from soils can result from environmental change and subsequent responses of plant and microbial communities and nutrient cycling. Explicit consideration of microbial life history traits and strategy may be necessary to predict climate feedbacks due to microbial physiology and community changes and their associated effect on carbon cycling. In this study, we developed an explicit microbial-enzyme decomposition model and examined model performance with and without representation of dormancy at six temperate forest sites with observed soil efflux ranged from 4 to 10 years across different forest types. We then extrapolated the model to all temperate forests in the Northern Hemisphere (25-50°N) to investigate spatial controls on microbial and soil C dynamics. Both models captured the observed soil heterotrophic respiration (RH), yet no-dormancy model consistently exhibited large seasonal amplitude and overestimation in microbial biomass. Spatially, the total RH from temperate forests based on dormancy model amounts to 6.88PgC/yr, and 7.99PgC/yr based on no-dormancy model. However, no-dormancy model notably overestimated the ratio of microbial biomass to SOC. Spatial correlation analysis revealed key controls of soil C:N ratio on the active proportion of microbial biomass, whereas local dormancy is primarily controlled by soil moisture and temperature, indicating scale-dependent environmental and biotic controls on microbial and SOC dynamics. These developments should provide essential support to modeling future soil carbon dynamics and enhance the avenue for collaboration between empirical soil experiment and modeling in the sense that more microbial physiological measurements are needed to better constrain and evaluate the models.

  19. Autoregulatory systems controlling translation factor expression: thermostat-like control of translational accuracy.

    PubMed

    Betney, Russell; de Silva, Eric; Krishnan, Jawahar; Stansfield, Ian

    2010-04-01

    In both prokaryotes and eukaryotes, the expression of a large number of genes is controlled by negative feedback, in some cases operating at the level of translation of the mRNA transcript. Of particular interest are those cases where the proteins concerned have cell-wide function in recognizing a particular codon or RNA sequence. Examples include the bacterial translation termination release factor RF2, initiation factor IF3, and eukaryote poly(A) binding protein. The regulatory loops that control their synthesis establish a negative feedback control mechanism based upon that protein's RNA sequence recognition function in translation (for example, stop codon recognition) without compromising the accurate recognition of that codon, or sequence during general, cell-wide translation. Here, the bacterial release factor RF2 and initiation factor IF3 negative feedback loops are reviewed and compared with similar negative feedback loops that regulate the levels of the eukaryote release factor, eRF1, established artificially by mutation. The control properties of such negative feedback loops are discussed as well as their evolution. The role of negative feedback to control translation factor expression is considered in the context of a growing body of evidence that both IF3 and RF2 can play a role in stimulating stalled ribosomes to abandon translation in response to amino acid starvation. Here, we make the case that negative feedback control serves primarily to limit the overexpression of these translation factors, preventing the loss of fitness resulting from an unregulated increase in the frequency of ribosome drop-off. PMID:20185543

  20. Social and cultural factors in the successful control of tuberculosis.

    PubMed Central

    Rubel, A J; Garro, L C

    1992-01-01

    The burden of tuberculosis on the public health is staggering. Worldwide, annual incidence of new cases is estimated to be about 8 million. Almost 3 million deaths occur yearly. Early case identification and adherence to treatment regimens are the remaining barriers to successful control. In many nations, however, fewer than half those with active disease receive a diagnosis, and fewer than half those beginning treatment complete it. The twin problems of delay in seeking treatment and abandonment of a prescribed regimen derive from complex factors. People's confusion as to the implications of the tuberculosis symptoms, costs of transportation to clinic services, the social stigma that attaches to tuberculosis, the high cost of medication, organizational problems in providing adequate followup services, and patients' perception of clinic facilities as inhospitable all contribute to the complexity. Sociocultural factors are emphasized in this report because hitherto they have not been adequately explored. Salient among those sociocultural factors is the health culture of the patients. That is, the understanding and information people have from family, friends, and neighbors as to the nature of a health problem, its cause, and its implications. A knowledge of the health culture of their patients has become a critical tool if tuberculosis control programs are to be successful. Several anthropological procedures are recommended to help uncover the health culture of people served by tuberculosis clinics. PMID:1454974

  1. Synthetic mammalian trigger-controlled bipartite transcription factors

    PubMed Central

    Folcher, Marc; Xie, Mingqi; Spinnler, Andrea; Fussenegger, Martin

    2013-01-01

    Synthetic biology has significantly advanced the design of synthetic control devices, gene circuits and networks that can reprogram mammalian cells in a trigger-inducible manner. Prokaryotic helix-turn-helix motifs have become the standard resource to design synthetic mammalian transcription factors that tune chimeric promoters in a small molecule-responsive manner. We have identified a family of Actinomycetes transcriptional repressor proteins showing a tandem TetR-family signature and have used a synthetic biology-inspired approach to reveal the potential control dynamics of these bi-partite regulators. Daisy-chain assembly of well-characterized prokaryotic repressor proteins such as TetR, ScbR, TtgR or VanR and fusion to either the Herpes simplex transactivation domain VP16 or the Krueppel-associated box domain (KRAB) of the human kox-1 gene resulted in synthetic bi- and even tri-partite mammalian transcription factors that could reversibly program their individual chimeric or hybrid promoters for trigger-adjustable transgene expression using tetracycline (TET), γ-butyrolactones, phloretin and vanillic acid. Detailed characterization of the bi-partite ScbR-TetR-VP16 (ST-TA) transcription factor revealed independent control of TET- and γ-butyrolactone-responsive promoters at high and double-pole double-throw (DPDT) relay switch qualities at low intracellular concentrations. Similar to electromagnetically operated mechanical DPDT relay switches that control two electric circuits by a fully isolated low-power signal, TET programs ST-TA to progressively switch from TetR-specific promoter-driven expression of transgene one to ScbR-specific promoter-driven transcription of transgene two while ST-TA flips back to exclusive transgene 1 expression in the absence of the trigger antibiotic. We suggest that natural repressors and activators with tandem TetR-family signatures may also provide independent as well as DPDT-mediated control of two sets of transgenes in

  2. Occupational factors associated with astrocytomas: a case-control study

    SciTech Connect

    Olin, R.G.; Ahlbom, A.; Lindberg-Navier, I.; Norell, S.E.; Spaennare, B.

    1987-01-01

    The most malignant form of all brain tumors is the supratentorial astrocytoma. Little is known about its etiology, but exogenous factors have been blamed. In this case-control study, 78 astrocytoma patients have been compared with 197 clinical and 92 population controls. An extensive questionnaire was used to gather information about occupational and residential environment exposure. Inquiries concerning groups of or individual chemicals elicited low rates of affirmative response, with negligible differences between cases and controls. However, the questions working at an airfield and living near a petrochemical plant indicated elevated risks in comparison with both control groups; so too did living near a municipal sewage treatment plant. These results focus attention on exposure to organic compounds and should be considered together with similar findings in current research. No other occupation, branch of industry, or vicinity questions showed differences between cases and controls, with the exception of living in the neighborhood of a paper mill or a saw mill, which gave moderately increased relative risks. A separate report gives the results from the nonoccupational part of the study.

  3. Shoreline as a controlling factor in commercial shrimp production

    NASA Technical Reports Server (NTRS)

    Faller, K. H. (Principal Investigator)

    1979-01-01

    The author has identified the following significant results. An ecological model was developed that relates marsh detritus export and shrimp production. It was based on the hypothesis that the shoreline is a controlling factor in the production of shrimp through regulation of detritus export from the marsh. LANDSAT data were used to develop measurement of shoreline length and areas of marsh having more than 5.0 kilometers of shoreline per square kilometer of area for the Louisiana coast, demonstrating the capability of remote sensing to provide important geographic information. These factors were combined with published tidal ranges and salinities to develop a mathematical model that predicted shrimp production for nine geographic units of the Louisiana coast, as indicated by the long term average commercial shrimp yield.

  4. Quality factor control in a lasing microcavity model

    PubMed

    Triandaf; Schwartz

    2000-04-01

    We consider a dynamics model of lasing microcavities, a class of optical resonators (1-10 &mgr;m in diameter) used in microlasers and for optical coupling of optical fibers. Inside such a cavity light circulates around the perimeter and is trapped by internal reflection. This is known as "whispering gallery" or high-Q modes. The cavity is a deformable cylindrical (or spherical) dielectric and at certain deformations light can escape by refraction. The quality of the resonator or Q factor, is defined as Q=omegatau, where tau is the escape time and omega is the frequency of light. We show that by appropriately deforming the cavity, the Q factor can be controlled by prolonging or shortening the average length of time spent by light trajectories inside the cavity. PMID:11088138

  5. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges.

    PubMed

    Prest, Emmanuelle I; Hammes, Frederik; van Loosdrecht, Mark C M; Vrouwenvelder, Johannes S

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  6. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    PubMed Central

    Prest, Emmanuelle I.; Hammes, Frederik; van Loosdrecht, Mark C. M.; Vrouwenvelder, Johannes S.

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  7. Transdiagnostic factors across fibromyalgia and mental disorders: sleep disturbances may play a key role. A clinical review.

    PubMed

    Palagini, Laura; Carmassi, Claudia; Conversano, Ciro; Gesi, Camilla; Bazzichi, Laura; Giacomelli, Camillo; Dell'Osso, Liliana

    2016-01-01

    Sleep disturbances, affective disorders, pain and fatigue are often present in individuals affected by fibromyalgia (FM). The pathophysiology of FM is not yet well understood and, to date, no treatment has been proven to be fully effective in alleviating all symptoms. Adopting a transdiagnostic perspective could thus be useful for clinicians: treatment would target a transdiagnostic process across a range of disturbances, not just a single disorder. The aim of this review is to revise the available literature about the potential role of sleep disturbances as a transdiagnostic process in FM symptomatology and mood or anxiety disorders comorbidity. We are proposing a model under which sleep disturbances can play a central role. Because conditions of sleep loss are related to the activation of the stress system, including the activation of the inflammation system, we propose this mechanism as a key one: it can be shared by mental, sleep disturbances and pain in FM and it may explain, in part, the high levels of comorbidity between them. In this frame-work sleep disturbances may play a key role and be the target of therapeutic strategies across FM symptomatology and mental disorders. PMID:27157399

  8. OsERF2 controls rice root growth and hormone responses through tuning expression of key genes involved in hormone signaling and sucrose metabolism.

    PubMed

    Xiao, Guiqing; Qin, Hua; Zhou, Jiahao; Quan, Ruidang; Lu, Xiangyang; Huang, Rongfeng; Zhang, Haiwen

    2016-02-01

    Root determines plant distribution, development progresses, stress response, as well as crop qualities and yields, which is under the tight control of genetic programs and environmental stimuli. Ethylene responsive factor proteins (ERFs) play important roles in plant growth and development. Here, the regulatory function of OsERF2 involved in root growth was investigated using the gain-function mutant of OsERF2 (nsf2857) and the artificial microRNA-mediated silenced lines of OsERF2 (Ami-OsERF2). nsf2857 showed short primary roots compared with the wild type (WT), while the primary roots of Ami-OsERF2 lines were longer than those of WT. Consistent with this phenotype, several auxin/cytokinin responsive genes involved in root growth were downregulated in nsf2857, but upregulated in Ami-OsERF2. Then, we found that nsf2857 seedlings exhibited decreased ABA accumulation and sensitivity to ABA and reduced ethylene-mediated root inhibition, while those were the opposite in Ami-ERF2 plants. Moreover, several key genes involved in ABA synthesis were downregulated in nsf2857, but unregulated in Ami-ERF2 lines. In addition, OsERF2 affected the accumulation of sucrose and UDPG by mediating expression of key genes involved in sucrose metabolism. These results indicate that OsERF2 is required for the control of root architecture and ABA- and ethylene-response by tuning expression of series genes involved in sugar metabolism and hormone signaling pathways. PMID:26659593

  9. Identification of a key regulatory element for the basal activity of the human insulin-like growth factor II gene promoter P3.

    PubMed Central

    Rietveld, L E; Holthuizen, P E; Sussenbach, J S

    1997-01-01

    Transcription of the human insulin-like growth factor II (IGF-II) gene is under the control of four promoters (P1-P4) that are differentially active during growth and development. Promoter 3 (P3) is the most active promoter during fetal development as well as in most adult tissues. P3 is also the most active promoter in tumour tissues and cell lines expressing IGF-II. Transient transfections of HeLa and Hep3B cells with truncated promoter constructs revealed that the region between -289 and -183 relative to the transcription start site supports basal promoter activity in both cell lines. Footprint experiments showed that the region between positions -192 and -172 (P3-4) is the only element bound by nuclear proteins. P3-4 is bound by five proteins, of which three proteins (proteins 3, 4 and 5) bind specifically and are expressed at the same levels in HeLa and Hep3B cells. Electrophoretic mobility shift assays and differential footprint experiments revealed the presence of two protein-binding regions within the P3-4 element. Proteins 4 and 5 bind box A (-193 to -188), whereas box B (-183 to -172) is bound by protein 3. From transcription experiments in vitro it can be concluded that Box A is essential for P3 activity. Box A is part of a region 11 dG residues long and is protected by proteins 4 and 5 that bind a contiguous set of six dG residues. DNA-binding of proteins 4 and 5 to box A requires the presence of Zn2+ ions. Thus structural and functional analysis reveals that the P3-4 element is a key regulatory element of P3 that contains two separate binding sites for proteins essential for the basal activity of IGF-II P3. PMID:9581544

  10. Human factors in remote control engineering development activities

    SciTech Connect

    Clarke, M.M.; Hamel, W.R.; Draper, J.V.

    1983-01-01

    Human factors engineering, which is an integral part of the advanced remote control development activities at the Oak Ridge National Laboratory, is described. First, work at the Remote Systems Development Facility (RSDF) has shown that operators can perform a wide variety of tasks, some of which were not specifically designed for remote systems, with a dextrous electronic force-reflecting servomanipulator and good television remote viewing capabilities. Second, the data collected during mock-up remote maintenance experiments at the RSDF have been analyzed to provide guidelines for the design of human interfaces with an integrated advanced remote maintenance system currently under development. Guidelines have been provided for task allocation between operators, remote viewing systems, and operator controls. 6 references, 5 figures, 2 tables.

  11. Risk factors for erysipelas of the leg (cellulitis): case-control study

    PubMed Central

    Dupuy, Alain; Benchikhi, Hakima; Roujeau, Jean-Claude; Bernard, Philippe; Vaillant, Loïc; Chosidow, Olivier; Sassolas, Bruno; Guillaume, Jean-Claude; Grob, Jean-Jacques; Bastuji-Garin, Sylvie

    1999-01-01

    Objective To assess risk factors for erysipelas of the leg (cellulitis). Design Case-control study. Setting 7 hospital centres in France. Subjects 167 patients admitted to hospital for erysipelas of the leg and 294 controls. Results In multivariate analysis, a disruption of the cutaneous barrier (leg ulcer, wound, fissurated toe-web intertrigo, pressure ulcer, or leg dermatosis) (odds ratio 23.8, 95% confidence interval 10.7 to 52.5), lymphoedema (71.2, 5.6 to 908), venous insufficiency (2.9, 1.0 to 8.7), leg oedema (2.5, 1.2 to 5.1) and being overweight (2.0, 1.1 to 3.7) were independently associated with erysipelas of the leg. No association was observed with diabetes, alcohol, or smoking. Population attributable risk for toe-web intertrigo was 61%. Conclusion This first case-control study highlights the major role of local risk factors (mainly lymphoedema and site of entry) in erysipelas of the leg. From a public health perspective, detecting and treating toe-web intertrigo should be evaluated in the secondary prevention of erysipelas of the leg. Key messagesLocal factors are potential risks for erysipelas of the legLymphoedema and disruption of the cutaneous barrier exhibit the highest relative riskToe-web intertrigo has a high population attributable risk, and its detection and treatment may prevent up to 60% of cases of erysipelas of the leg PMID:10364117

  12. The Four Key Factors for Commercializing Research: The Case of a Young University in a Region in Crisis.

    ERIC Educational Resources Information Center

    Laperche, Blandine

    2002-01-01

    Investigated factors in the successful commercialization of public research from higher education and then applied the ideas gleaned from a review of several case studies to the case of a young French university. Findings show the importance of close interaction between academic research and a wealthy local economy, lacking in the case of the…

  13. Factors Impacting Student Service Utilization at Ontario Colleges: Key Performance Indicators as a Measure of Success: A Niagara College View

    ERIC Educational Resources Information Center

    Veres, David

    2015-01-01

    Student success in Ontario College is significantly influenced by the utilization of student services. At Niagara College there has been a significant investment in student services as a strategy to support student success. Utilizing existing KPI data, this quantitative research project is aimed at measuring factors that influence both the use of…

  14. Life cycle assessment of lignocellulosic ethanol: a review of key factors and methods affecting calculated GHG emissions and energy use.

    PubMed

    Gerbrandt, Kelsey; Chu, Pei Lin; Simmonds, Allison; Mullins, Kimberley A; MacLean, Heather L; Griffin, W Michael; Saville, Bradley A

    2016-04-01

    Lignocellulosic ethanol has potential for lower life cycle greenhouse gas emissions compared to gasoline and conventional grain-based ethanol. Ethanol production 'pathways' need to meet economic and environmental goals. Numerous life cycle assessments of lignocellulosic ethanol have been published over the last 15 years, but gaps remain in understanding life cycle performance due to insufficient data, and model and methodological issues. We highlight key aspects of these issues, drawing on literature and a case study of corn stover ethanol. Challenges include the complexity of feedstock/ecosystems and market-mediated aspects and the short history of commercial lignocellulosic ethanol facilities, which collectively have led to uncertainty in GHG emissions estimates, and to debates on LCA methods and the role of uncertainty in decision making. PMID:26807514

  15. Aging is a primary risk factor for cardiac arrhythmias: disruption of intracellular Ca2+ regulation as a key suspect.

    PubMed

    Hatch, Fiona; Lancaster, Matthew K; Jones, Sandra A

    2011-08-01

    Aging is an inevitable time-dependent progression associated with a functional decline of the cardiovascular system even in 'healthy' individuals. Age positively correlates with an increasing risk of cardiac problems including arrhythmias. Not only the prevalence but also the severity of arrhythmias escalates with age. The reasons for this are multifactorial but dysregulation of intracellular calcium within the heart is likely to play a key role in initiating and perpetuating these life-threatening events. We now know that several aspects of cardiac calcium regulation significantly change with advancing age - changes that could produce electrical instability. Further development of knowledge of the mechanisms underlying these changes will allow us to reduce what currently is an inevitable increase in the incidence of arrhythmias in the elderly. PMID:21878050

  16. Where to Forage in the Absence of Sea Ice? Bathymetry As a Key Factor for an Arctic Seabird.

    PubMed

    Amélineau, Françoise; Grémillet, David; Bonnet, Delphine; Le Bot, Tangi; Fort, Jérôme

    2016-01-01

    The earth is warming at an alarming rate, especially in the Arctic, where a marked decline in sea ice cover may have far-ranging consequences for endemic species. Little auks, endemic Arctic seabirds, are key bioindicators as they forage in the marginal ice zone and feed preferentially on lipid-rich Arctic copepods and ice-associated amphipods sensitive to the consequences of global warming. We tested how little auks cope with an ice-free foraging environment during the breeding season. To this end, we took advantage of natural variation in sea ice concentration along the east coast of Greenland. We compared foraging and diving behaviour, chick diet and growth and adult body condition between two years, in the presence versus nearby absence of sea ice in the vicinity of their breeding site. Moreover, we sampled zooplankton at sea when sea ice was absent to evaluate prey location and little auk dietary preferences. Little auks foraged in the same areas both years, irrespective of sea ice presence/concentration, and targeted the shelf break and the continental shelf. We confirmed that breeding little auks showed a clear preference for larger copepod species to feed their chick, but caught smaller copepods and nearly no ice-associated amphipod when sea ice was absent. Nevertheless, these dietary changes had no impact on chick growth and adult body condition. Our findings demonstrate the importance of bathymetry for profitable little auk foraging, whatever the sea-ice conditions. Our investigations, along with recent studies, also confirm more flexibility than previously predicted for this key species in a warming Arctic. PMID:27438790

  17. Where to Forage in the Absence of Sea Ice? Bathymetry As a Key Factor for an Arctic Seabird

    PubMed Central

    Amélineau, Françoise; Grémillet, David; Bonnet, Delphine; Le Bot, Tangi; Fort, Jérôme

    2016-01-01

    The earth is warming at an alarming rate, especially in the Arctic, where a marked decline in sea ice cover may have far-ranging consequences for endemic species. Little auks, endemic Arctic seabirds, are key bioindicators as they forage in the marginal ice zone and feed preferentially on lipid-rich Arctic copepods and ice-associated amphipods sensitive to the consequences of global warming. We tested how little auks cope with an ice-free foraging environment during the breeding season. To this end, we took advantage of natural variation in sea ice concentration along the east coast of Greenland. We compared foraging and diving behaviour, chick diet and growth and adult body condition between two years, in the presence versus nearby absence of sea ice in the vicinity of their breeding site. Moreover, we sampled zooplankton at sea when sea ice was absent to evaluate prey location and little auk dietary preferences. Little auks foraged in the same areas both years, irrespective of sea ice presence/concentration, and targeted the shelf break and the continental shelf. We confirmed that breeding little auks showed a clear preference for larger copepod species to feed their chick, but caught smaller copepods and nearly no ice-associated amphipod when sea ice was absent. Nevertheless, these dietary changes had no impact on chick growth and adult body condition. Our findings demonstrate the importance of bathymetry for profitable little auk foraging, whatever the sea-ice conditions. Our investigations, along with recent studies, also confirm more flexibility than previously predicted for this key species in a warming Arctic. PMID:27438790

  18. Factors controlling phosphorus release from sediments in coastal archipelago areas.

    PubMed

    Puttonen, Irma; Kohonen, Tuula; Mattila, Johanna

    2016-07-15

    In coastal archipelago areas of the northern Baltic Sea, significantly higher phosphate concentrations (6.0±4.5μmol/l, mean±SD) were measured in water samples close to the sediment surface compared with those from 1m above the seafloor (1.6±2.0μmol/l). The results indicated notable phosphate release from sediments under the bottom water oxygen concentrations of up to 250μmol/l, especially in areas that had experienced recent temporal fluctuation between oxic and hypoxic/anoxic conditions. No single factor alone was found to control the elevated PO4-P concentrations in the near-bottom water. In addition to the oxygen in the water, the contents of potentially mobile phosphorus fractions, grain-size, the organic content at the sediment surface, and the water depth were all important factors controlling the internal loading of phosphorus. The complexity of this process needs to be accounted for in assessments of the internal loading of phosphorus and in potential mitigation plans. PMID:27184132

  19. Controlled release of growth factors for regenerative medicine.

    PubMed

    Liu, Libiao; Zhou, Xinwei; Xu, Yufan; Zhang, Weiming; Liu, Cheng-Hsien; Wang, Xiaohong

    2015-01-01

    How to release growth factors (GFs) scientifically to promote stem cell proliferation and differentiation is one of the most significant research focuses in the field of regenerative medicine. In a controlled release system, growth factors, extracellular matrices or biomaterial carriers, and sometimes stem cells together form a geometric entirety. Biomaterial carriers provide GFs with a support structure to be adhered, immobilized, encapsulated or/and protected. As a unity, the release rate and rhythm of GFs on cells are normally very delicate and precise. Up to now, the best strategy for clinical applications is the combination systems that encapsulate GFs in microspheres, particularly the nano- or micro-encapsulation techniques integrated GFs with biomaterial carriers. In this mini review, we summarize the current progress in GF delivery systems for regenerative medicine and provide an outlook on two main aspects: one is the classes of stem cells and GFs that have been used frequently in regenerative medicine, including their respective application conditions and functions; the other is the controlled GF release systems, in which various GFs are released orderly and continuously without diffusing simply and rapidly, including their respective opportunities and challenges. PMID:25594403

  20. Dentine sensitivity risk factors: A case–control study

    PubMed Central

    Mafla, Ana Cristina; Lopez-Moncayo, Luis Fernando

    2016-01-01

    Objective: To identify the clinical and psychological risk factors associated with dentine hypersensitivity (DH) in order to provide an early diagnosis and preventive therapy. Materials and Methods: A nested case–control study was design between 2011 and 2012. A total of 61 DH cases and 122 controls participated in this investigation. Cases and controls were matched for sex, group of age and socioeconomic status in a ratio of 1:2. DH to different stimuli such as cold, heat, acid, and sweet was asked in patient interviews, and dental examinations were used to detect DH. Clinical and psychological risk factors such as dental hygiene, periodontal disease, acid diet, alcohol consumption, psychological stress, and psychopathological symptoms were inquired. Psychological stress was measured through the PSS-10 and psychopathological symptoms were evaluated by SCL-90-R in Spanish. Descriptive and univariate binary logistic regression analysis were performed to estimate the association between clinical and psychological risk factors and the presence of DH. Results: Toothpaste abrasivity (odds ratio [OR] 1.881, 95% confidence interval [CI] 1.010–3.502, P = 0.045), gingival recession (OR 2.196, 95% CI 1.020–4.728, P = 0.041), and periodontal therapy (OR 5.357, 95% CI 2.051–13.993, P < 0.001) were associated with DH. Subjects with perceived stress (OR 1.211, 95%, CI 0.518–2.833, P = 0.658), obsessive-compulsive (OR 1.266, 95%, CI 0.494–3.240, P = 0.623) and hostility (OR 1.235, 95%, CI 0.507–3.007, P = 0.642) symptoms had a clinical greater odd of DH. Conclusion: Oral hygiene products and periodontal conditions are important risk factors for DH. Individuals with perceived stress, obsessive-compulsive, and hostility symptoms may increase a clinical risk for this entity. Targeting to dental counseling focused on oral hygiene products, periodontal therapy and a psychological evaluation may be promising in DH prevention. PMID:27011732

  1. Some key environmental variables controlling nitrous oxide emissions from agricultural and semi-natural soils in Scotland

    NASA Astrophysics Data System (ADS)

    Skiba, U. M.; Sheppard, L. J.; Macdonald, J.; Fowler, D.

    Soil N 2O emissions were measured from a range of mineral soils (22 sites) supporting woodlands, grassland and agriculture between 1991 and 1996 and were co-analysed in order to establish some overriding relationships between the N 2O emission and soil temperature, water content, available NH +4 and NO -3, pH and N input by fertiliser, manure and atmospheric deposition. Fluxes were measured by chamber techniques. For individual sites, nitrogen, soil temperature and water content were the key variables controlling the emission rates. Nitrogen additions by fertilisation, manure and atmospheric deposition increased the emissions of N 2O. From pasture grazed by sheep 1.7% of the N input from fertiliser and animal excreta was emitted as N 2O. For an experimental sitka spruce plantation receiving acid mist and a mixed woodland in the immediate vicinity of a poultry farm losses of N 2O were estimated at 3.7 and 0.8% of the atmospheric N deposited, respectively. In spite of the large variations in land use, soil physical and chemical characteristics of the 22 data sets collected at different years and at varying frequency, the mean flux from each site could be described by following multiple regression equation: log N 2O ( μg N m -2 h -1)=-1.04+0.165∗soil temperature+0.403∗log N input (kg N ha -1 yr -1) -0.0145∗gravimetric soil water content (% soil dry weight).

  2. Foxo transcription factors control regulatory T cell development and function

    PubMed Central

    Kerdiles, Yann M.; Stone, Erica L.; Beisner, Daniel L.; McGargill, Maureen A.; Ch'en, Irene L.; Stockmann, Christian; Katayama, Carol D.; Hedrick, Stephen M.

    2010-01-01

    SUMMARY Foxo transcription factors integrate extrinsic signals to regulate cell division, differentiation and survival, and specific functions of lymphoid and myeloid cells. Here we showed the absence of Foxo1 severely curtailed the development of Foxp3+ regulatory T (Treg) cells, and those that developed were nonfunctional in vivo. The loss of function included diminished CTLA-4 receptor expression as the Ctla4 gene was a direct target of Foxo1. T cell specific loss of Foxo1 resulted in exocrine pancreatitis, hind limb paralysis, multi-organ lymphocyte infiltration, anti-nuclear antibodies and expanded germinal centers. Foxo-mediated control over Treg cell specification was further revealed by the inability of TGF-β cytokine to suppress T-bet transcription factor in the absence of Foxo1, resulting in IFN-γ-secretion. In addition the absence of Foxo3 exacerbated the effects of the loss of Foxo1. Thus, Foxo transcription factors guide the contingencies of T cell differentiation and specific functions of effector cell populations. PMID:21167754

  3. Individual and Population Level Impact of Key HIV Risk Factors on HIV Incidence Rates in Durban, South Africa

    PubMed Central

    Ramjee, Gita; Moonsamy, Suri; Abbai, Nathlee Samantha; Wand, Handan

    2016-01-01

    We aimed to estimate the individual and joint impact of age, marital status and diagnosis with sexually transmitted infections (STIs) on HIV acquisition among young women at a population level in Durban, KwaZulu-Natal, South Africa. A total of 3,978 HIV seronegative women were recruited for four biomedical intervention trials from 2002–2009. Point and interval estimates of partial population attributable risk (PAR) were used to quantify the proportion of HIV seroconversions which can be prevented if a combination of risk factors is eliminated from a target population. More than 70% of the observed HIV acquisitions were collectively attributed to the three risk factors: younger age (<25 years old), unmarried and not cohabiting with a stable/regular partner and diagnosis with STIs. Addressing these risks requires targeted structural, behavioural, biomedical and cultural interventions in order to impact on unacceptably high HIV incidence rates among young women and the population as a whole. PMID:27104835

  4. Control of Dual-Opposed Stirling Convertors with Active Power Factor Correction Controllers

    NASA Technical Reports Server (NTRS)

    Regan, Timothy F.; Lewandowski, Edward J.; Schreiber, Jeffrey G.

    2006-01-01

    When using recently-developed active power factor correction (APFC) controllers in power systems comprised of dual-opposed free-piston Stirling convertors, a variety of configurations of the convertors and controller(s) can be considered, with configuration ultimately selected based on benefits of efficiency, reliability, and robust operation. The configuration must not only achieve stable control of the two convertors, but also synchronize and regulate motion of the pistons to minimize net dynamic forces. The NASA Glenn Research Center (GRC) System Dynamic Model (SDM) was used to study ten configurations of dual-opposed convertor systems. These configurations considered one controller with the alternators connected in series or in parallel, and two controllers with the alternators not connected (isolated). For the configurations where the alternators were not connected, several different approaches were evaluated to synchronize the two convertors. In addition, two thermodynamic configurations were considered: two convertors with isolated working spaces and convertors with a shared expansion space. Of the ten configurations studied, stable operating modes were found for four. Three of those four had a common expansion space. One stable configuration was found for the dual-opposed convertors with separate working spaces. That configuration required isochronous control of both convertors, and two APFC controllers were used to accomplish this. A frequency/phase control loop was necessary to allow each APFC controller to synchronize its associated convertor with a common frequency.

  5. Control of Dual-Opposed Stirling Convertors with Active Power Factor Correction Controllers

    NASA Technical Reports Server (NTRS)

    Regan, Timothy F.; Lewandowski, Edward J.; Schreiber, Jeffrey G.

    2007-01-01

    When using recently-developed active power factor correction (APFC) controllers in power systems comprised of dual-opposed free-piston Stirling convertors, a variety of configurations of the convertors and controller(s) can be considered, with configuration ultimately selected based on benefits of efficiency, reliability, and robust operation. The configuration must not only achieve stable control of the two convertors, but also synchronize and regulate motion of the pistons to minimize net dynamic forces. The NASA Glenn Research Center (GRC) System Dynamic Model (SDM) was used to study ten configurations of dual-opposed convertor systems. These configurations considered one controller with the alternators connected in series or in parallel, and two controllers with the alternators not connected (isolated). For the configurations where the alternators were not connected, several different approaches were evaluated to synchronize the two convertors. In addition, two thermodynamic configurations were considered: two convertors with isolated working spaces and convertors with a shared expansion space. Of the ten configurations studied, stable operating modes were found for four. Three of those four had a common expansion space. One stable configuration was found for the dual-opposed convertors with separate working spaces. That configuration required isochronous control of both convertors, and two APFC controllers were used to accomplish this. A frequency/phase control loop was necessary to allow each APFC controller to synchronize its associated convertor with a common frequency.

  6. The Postgraduate Hospital Educational Environment Measure (PHEEM) Questionnaire Identifies Quality of Instruction as a Key Factor Predicting Academic Achievement

    PubMed Central

    Vieira, Joaquim Edson

    2008-01-01

    OBJECTIVE This study analyzes the reliability of the PHEEM questionnaire translated into Portuguese. We present the results of PHEEM following distribution to doctors in three different medical residency programs at a university hospital in Brazil. INTRODUCTION Efforts to understand environmental factors that foster effective learning resulted in the development of a questionnaire to measure medical residents’ perceptions of the level of autonomy, teaching quality and social support in their programs. METHODS The questionnaire was translated using the modified Brislin back-translation technique. Cronbach’s alpha test was used to ensure good reliability and ANOVA was used to compare PHEEM results among residents from the Surgery, Anesthesiology and Internal Medicine departments. The Kappa coefficient was used as a measure of agreement, and factor analysis was employed to evaluate the construct strength of the three domains suggested by the original PHEEM questionnaire. RESULTS The PHEEM survey was completed by 306 medical residents and the resulting Cronbach’s alpha was 0.899. The weighted Kappa was showed excellent reliability. Autonomy was rated most highly by Internal Medicine residents (63.7% ± 13.6%). Teaching was rated highest in Anesthesiology (66.7% ± 15.4%). Residents across the three areas had similar perceptions of social support (59.0% ± 13.3% for Surgery; 60.5% ± 13.6% for Internal Medicine; 61.4% ± 14.4% for Anesthesiology). Factor analysis suggested that nine factors explained 58.9% of the variance. CONCLUSIONS This study indicates that PHEEM is a reliable instrument for measuring the quality of medical residency programs at a Brazilian teaching hospital. The results suggest that quality of teaching was the best indicator of overall response to the questionnaire. PMID:19060994

  7. Occupational Risk Factors for COPD: A Case-Control Study

    PubMed Central

    Drame, Moustapha; Lebargy, Francois; Deschamps, Frédéric

    2016-01-01

    Objectives The aim of this research was to examine the occupational risk factors for Chronic Obstructive Pulmonary Diseases (COPD) in a range of occupations. Methods Eleven occupations involving different types of exposure were observed in this multicenter case-control study. Controls and cases were matched for sex, age and smoking. Multiple logistic regression analyses were used to estimate odds ratios (ORs). Results A total of 1,519 participants were initially recruited between September 2004 and September 2012. After matching, 547 pairs were obtained. The mean age was 56.3 +/- 10.4 years. Smelter workers were the only ones with an increased risk of COPD in this study (OR = 7.6, p < 0.0001, 95% CI [4.5, 12.9]). Physical activity was protective (OR = 0.7), while living in the city was a risk (OR = 1.6). The main used metals were cast iron, aluminum and alloys. Molds and cores were mainly made from sand and synthetic resins. Machine maintenance (65.2%), molding (49.6%), finishing (41.1%) and casting (41.0%) were the most common activities. Almost all workers (95.1%) cleaned the floors and machines with a brush or compressed air. Conclusions This study demonstrates the importance of occupational factors in the genesis of COPD, especially among smelter workers. As with the fight against smoking-related disease, the removal or substitution of recognized hazardous agents is the best way of preventing the onset of COPD. This is why it is essential to continue research on its occupational risk factors. PMID:27487078

  8. Statistical key factors optimization of conditions for hydrogen production from S-TE (solubilization by thermophilic enzyme) waste sludge.

    PubMed

    Guo, Liang; Zhao, Jun; She, Zonglian; Lu, Mingmin; Zong, Yan

    2013-06-01

    Waste sludge can be solubilized after S-TE (solubilization by thermophilic enzyme) pretreatment as the cryptic growth occurs at the expense of the cell lysate. The hydrogen production from S-TE sludge is greatly influenced by many factors. In this study, factors including pH, C/N, C/P, and Fe(2+) affecting hydrogen production from S-TE sludge were optimized using uniform design. The optimum condition for maximum hydrogen yield of 68.4 ml H2/g VSS (volatile suspended solid) could be predicted from regression model, and the optimum conditions were pH of 6.4, C/N ratio of 38, C/P ratio of 265, and Fe(2+) concentration of 85 mg/L. There was interaction effect of factors on hydrogen production from S-TE sludge. Different pH, C/N, C/P and Fe(2+) conditions could influence the VSS removal rate, carbohydrate and protein utilization. When the highest compositions of acetate and ethanol and lowest propionate were observed in metabolites, effective hydrogen production was also achieved. PMID:23584408

  9. Sterol Regulatory Transcription Factor-1: Key Regulator of Fasting Response in the Adipose Tissue inGPigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genetic mechanisms controlling appetite and feeding behaviors are not well understood. In this study, transcriptional profiling was used to identify porcine genes and pathways that respond to a fasting treatment or to a missense mutation (D298N) in the melanocortin-4 receptor (MC4R) gene, which...

  10. Key Factors for the Development of a Culturally Appropriate Interactive Multimedia Informative Program for Aboriginal Health Workers

    ERIC Educational Resources Information Center

    El Sayed, Faeka; Soar, Jeffrey; Wang, Zoe

    2012-01-01

    This research aims to create and evaluate a model for a culturally appropriate, interactive, multimedia and informative health program for Aboriginal and Torres Strait Islander health workers that aims to improve the capacity to independently control their learning within an attractive learning environment. The research also aims to provide…

  11. Factors Predicting Atypical Development of Nighttime Bladder Control

    PubMed Central

    Sullivan, Sarah; Heron, Jon

    2015-01-01

    ABSTRACT: Objective: To derive latent classes (longitudinal “phenotypes”) of frequency of bedwetting from 4 to 9 years and to examine their association with developmental delay, parental history of bedwetting, length of gestation and birth weight. Method: The authors used data from 8,769 children from the UK Avon Longitudinal Study of Parents and Children cohort. Mothers provided repeated reports on their child's frequency of bedwetting from 4 to 9 years. The authors used longitudinal latent class analysis to derive latent classes of bedwetting and examined their association with sex, developmental level at 18 months, parental history of wetting, birth weight, and gestational length. Results: The authors identified 5 latent classes: (1) “normative”—low probability of bedwetting; (2) “infrequent delayed”—delayed attainment of nighttime bladder control with bedwetting control with bedwetting ≥ twice a week; (4) “infrequent persistent”—persistent bedwetting < twice a week; and (5) “frequent persistent”—persistent bedwetting ≥ twice a week. Male gender (odds ratio = 3.20 [95% confidence interval = 2.36–4.34]), developmental delay, for example, delayed social skills (1.33 [1.11–1.58]), and maternal history of wetting (3.91 [2.60–5.88]) were associated with an increase in the odds of bedwetting at 4 to 9 years. There was little evidence that low birth weight and shorter gestation period were associated with bedwetting. Conclusion: The authors described patterns of development of nighttime bladder control and found evidence for factors that predict continuation of bedwetting at school age. Increased knowledge of risk factors for bedwetting is needed to identify children at risk of future problems attaining and maintaining continence. PMID:26468941

  12. The monitoring and control of TRUEX processes. Volume 1, The use of sensitivity analysis to determine key process variables and their control bounds

    SciTech Connect

    Regalbuto, M.C.; Misra, B.; Chamberlain, D.B.; Leonard, R.A.; Vandegrift, G.F.

    1992-04-01

    The Generic TRUEX Model (GTM) was used to design a flowsheet for the TRUEX solvent extraction process that would be used to determine its instrumentation and control requirements. Sensitivity analyses of the key process variables, namely, the aqueous and organic flow rates, feed compositions, and the number of contactor stages, were carried out to assess their impact on the operation of the TRUEX process. Results of these analyses provide a basis for the selection of an instrument and control system and the eventual implementation of a control algorithm. Volume Two of this report is an evaluation of the instruments available for measuring many of the physical parameters. Equations that model the dynamic behavior of the TRUEX process have been generated. These equations can be used to describe the transient or dynamic behavior of the process for a given flowsheet in accordance with the TRUEX model. Further work will be done with the dynamic model to determine how and how quickly the system responds to various perturbations. The use of perturbation analysis early in the design stage will lead to a robust flowsheet, namely, one that will meet all process goals and allow for wide control bounds. The process time delay, that is, the speed with which the system reaches a new steady state, is an important parameter in monitoring and controlling a process. In the future, instrument selection and point-of-variable measurement, now done using the steady-state results reported here, will be reviewed and modified as necessary based on this dynamic method of analysis.

  13. STAT5 is a key transcription factor for IL-3-mediated inhibition of RANKL-induced osteoclastogenesis

    PubMed Central

    Lee, Jongwon; Seong, Semun; Kim, Jung Ha; Kim, Kabsun; Kim, Inyoung; Jeong, Byung-chul; Nam, Kwang-Il; Kim, Kyung Keun; Hennighausen, Lothar; Kim, Nacksung

    2016-01-01

    Among the diverse cytokines involved in osteoclast differentiation, interleukin (IL)-3 inhibits RANKL-induced osteoclastogenesis. However, the mechanism underlying IL-3-mediated inhibition of osteoclast differentiation is not fully understood. Here we demonstrate that the activation of signal transducers and activators of transcription 5 (STAT5) by IL-3 inhibits RANKL-induced osteoclastogenesis through the induction of the expression of Id genes. We found that STAT5 overexpression inhibited RANKL-induced osteoclastogenesis. However, RANKL did not regulate the expression or activation of STAT5 during osteoclast differentiation. STAT5 deficiency prevented IL-3-mediated inhibition of osteoclastogenesis, suggesting a key role of STAT5 in IL-3-mediated inhibition of osteoclast differentiation. In addition, IL-3-induced STAT5 activation upregulated the expression of Id1 and Id2, which are negative regulators of osteoclastogenesis. Overexpression of ID1 or ID2 in STAT5-deficient cells reversed osteoclast development recovered from IL-3-mediated inhibition. Importantly, microcomputed tomography and histomorphometric analysis revealed that STAT5 conditional knockout mice showed reduced bone mass, with an increased number of osteoclasts. Furthermore, IL-3 inhibited RANKL-induced osteoclast differentiation less effectively in the STAT5 conditional knockout mice than in the wild-type mice after RANKL injection. Taken together, our findings indicate that STAT5 contributes to the remarkable IL-3-mediated inhibition of RANKL-induced osteoclastogenesis by activating Id genes and their associated pathways. PMID:27485735

  14. STAT5 is a key transcription factor for IL-3-mediated inhibition of RANKL-induced osteoclastogenesis.

    PubMed

    Lee, Jongwon; Seong, Semun; Kim, Jung Ha; Kim, Kabsun; Kim, Inyoung; Jeong, Byung-Chul; Nam, Kwang-Il; Kim, Kyung Keun; Hennighausen, Lothar; Kim, Nacksung

    2016-01-01

    Among the diverse cytokines involved in osteoclast differentiation, interleukin (IL)-3 inhibits RANKL-induced osteoclastogenesis. However, the mechanism underlying IL-3-mediated inhibition of osteoclast differentiation is not fully understood. Here we demonstrate that the activation of signal transducers and activators of transcription 5 (STAT5) by IL-3 inhibits RANKL-induced osteoclastogenesis through the induction of the expression of Id genes. We found that STAT5 overexpression inhibited RANKL-induced osteoclastogenesis. However, RANKL did not regulate the expression or activation of STAT5 during osteoclast differentiation. STAT5 deficiency prevented IL-3-mediated inhibition of osteoclastogenesis, suggesting a key role of STAT5 in IL-3-mediated inhibition of osteoclast differentiation. In addition, IL-3-induced STAT5 activation upregulated the expression of Id1 and Id2, which are negative regulators of osteoclastogenesis. Overexpression of ID1 or ID2 in STAT5-deficient cells reversed osteoclast development recovered from IL-3-mediated inhibition. Importantly, microcomputed tomography and histomorphometric analysis revealed that STAT5 conditional knockout mice showed reduced bone mass, with an increased number of osteoclasts. Furthermore, IL-3 inhibited RANKL-induced osteoclast differentiation less effectively in the STAT5 conditional knockout mice than in the wild-type mice after RANKL injection. Taken together, our findings indicate that STAT5 contributes to the remarkable IL-3-mediated inhibition of RANKL-induced osteoclastogenesis by activating Id genes and their associated pathways. PMID:27485735

  15. Key Factors Affecting Reproductive Success of Thoroughbred Mares and Stallions on a Commercial Stud Farm.

    PubMed

    Lane, E A; Bijnen, Mlj; Osborne, M; More, S J; Henderson, Isf; Duffy, P; Crowe, M A

    2016-04-01

    To evaluate factors contributing to fertility of thoroughbred mares, data from 3743 oestrous periods of 2385 mares were collected on a large thoroughbred farm in Ireland. Fourteen stallions (mean age 8.3 years; range 4-15 years) had bred 2385 mares (mean age 9.4 years; range 3-24 years). Maiden mares accounted for 12%, mares with a foal at foot for 64%, and barren, slipped or rested mares for 24% of the total. The mean pregnancy rate per cycle was 67.8% (68.6% in year 1 and 66.9% in year 2). Backward stepwise multivariable logistic regression analysis was utilized to develop two models to evaluate mare factors, including mare age, reproductive status, month of foaling, dystocia, month of cover, foal heat, cycle number, treatments, walk-in status and stallion factors including stallion identity, stallion age, shuttle status, time elapsed between covers and high stallion usage on the per cycle pregnancy rate and pregnancy loss. Old age (p < 0.001) and cover within 20 days post-partum (p < 0.003) were associated with lowered pregnancy rates. High mare age (p < 0.05) and barren, slipped or rested reproductive status (p = 0.05) increased the likelihood of pregnancy loss. Uterine inflammation or infection, if appropriately treated, did not affect fertility. Only high usage of stallions (used more than 21 times in previous week) was associated with lowered (p = 0.009) pregnancy rates. However, shuttle stallions were more likely to have increased (p = 0.035) pregnancy survival, perhaps reflecting a bias in stallion selection. In conclusion, mare age exerted the greatest influence on fertility; nonetheless, thoroughbreds can be effectively managed to achieve high reproductive performance in a commercial setting. PMID:26815482

  16. Early growth response transcription factors: key mediators of fibrosis and novel targets for anti-fibrotic therapy

    PubMed Central

    Bhattacharyya, Swati; Wu, Minghua; Fang, Feng; Tourtellotte, Warren; Feghali-Bostwick, Carol; Varga, John

    2011-01-01

    Fibrosis is a deregulated and ultimately defective form of tissue repair that underlies a large number of chronic human diseases, as well as obesity and aging. The pathogenesis of fibrosis involves multiple cell types and extracellular signals, of which transforming growth factor- β (TGF-β) is pre-eminent. The prevalence of fibrosis is rising worldwide, and to date no agents has shown clinical efficacy in the attenuating or reversing the process. Recent studies implicate the immediate-early response transcription factor Egr-1 in the pathogenesis of fibrosis. Egr-1 couples acute changes in the cellular environment to sustained alterations in gene expression, and mediates a broad spectrum of biological responses to injury and stress. In contrast to other ligand-activated transcription factors such as NF-κB, c-jun and Smad2/3 that undergo post-translational modification such as phosphorylation and nuclear translocation, Egr-1 activity is regulated via its biosynthesis. Aberrant Egr-1 expression or activity is implicated in cancer, inflammation, atherosclerosis, and ischemic injury and recent studies now indicate an important role for Egr-1 in TGF-β-dependent profibrotic responses. Fibrosis in various animal models and human diseases such as scleroderma (SSc) and idiopathic pulmonary fibrosis (IPF) is accompanied by aberrant Egr-1 expression. Moreover Egr-1 appears to be required for physiologic and pathological connective tissue remodeling, and Egr-1-null mice are protected from fibrosis. As a novel profibrotic mediator, Egr-1 thus appears to be a promising potential target for the development of anti-fibrotic therapies. PMID:21511034

  17. Quantitative Circadian Phosphoproteomic Analysis of Arabidopsis Reveals Extensive Clock Control of Key Components in Physiological, Metabolic, and Signaling Pathways*

    PubMed Central

    Choudhary, Mani Kant; Nomura, Yuko; Wang, Lei; Nakagami, Hirofumi; Somers, David E.

    2015-01-01

    The circadian clock provides adaptive advantages to an organism, resulting in increased fitness and survival. The phosphorylation events that regulate circadian-dependent signaling and the processes which post-translationally respond to clock-gated signals are largely unknown. To better elucidate post-translational events tied to the circadian system we carried out a survey of circadian-regulated protein phosphorylation events in Arabidopsis seedlings. A large-scale mass spectrometry-based quantitative phosphoproteomics approach employing TiO2-based phosphopeptide enrichment techniques identified and quantified 1586 phosphopeptides on 1080 protein groups. A total of 102 phosphopeptides displayed significant changes in abundance, enabling the identification of specific patterns of response to circadian rhythms. Our approach was sensitive enough to quantitate oscillations in the phosphorylation of low abundance clock proteins (EARLY FLOWERING4; ELF4 and PSEUDORESPONSE REGULATOR3; PRR3) as well as other transcription factors and kinases. During constant light, extensive cyclic changes in phosphorylation status occurred in critical regulators, implicating direct or indirect regulation by the circadian system. These included proteins influencing transcriptional regulation, translation, metabolism, stress and phytohormones-mediated responses. We validated our analysis using the elf4–211 allele, in which an S45L transition removes the phosphorylation herein identified. We show that removal of this phosphorylatable site diminishes interaction with EARLY FLOWERING3 (ELF3), a key partner in a tripartite evening complex required for circadian cycling. elf4–211 lengthens period, which increases with increasing temperature, relative to the wild type, resulting in a more stable temperature compensation of circadian period over a wider temperature range. PMID:26091701

  18. IGF-I: A Key Growth Factor that Regulates Neurogenesis and Synaptogenesis from Embryonic to Adult Stages of the Brain

    PubMed Central

    Nieto-Estévez, Vanesa; Defterali, Çağla; Vicario-Abejón, Carlos

    2016-01-01

    The generation of neurons in the adult mammalian brain requires the activation of quiescent neural stem cells (NSCs). This activation and the sequential steps of neuron formation from NSCs are regulated by a number of stimuli, which include growth factors. Insulin-like growth factor-I (IGF-I) exert pleiotropic effects, regulating multiple cellular processes depending on their concentration, cell type, and the developmental stage of the animal. Although IGF-I expression is relatively high in the embryonic brain its levels drop sharply in the adult brain except in neurogenic regions, i.e., the hippocampus (HP) and the subventricular zone-olfactory bulb (SVZ-OB). By contrast, the expression of IGF-IR remains relatively high in the brain irrespective of the age of the animal. Evidence indicates that IGF-I influences NSC proliferation and differentiation into neurons and glia as well as neuronal maturation including synapse formation. Furthermore, recent studies have shown that IGF-I not only promote adult neurogenesis by regulating NSC number and differentiation but also by influencing neuronal positioning and migration as described during SVZ-OB neurogenesis. In this article we will revise and discuss the actions reported for IGF-I signaling in a variety of in vitro and in vivo models, focusing on the maintenance and proliferation of NSCs/progenitors, neurogenesis, and neuron integration in synaptic circuits. PMID:26941597

  19. IGF-I: A Key Growth Factor that Regulates Neurogenesis and Synaptogenesis from Embryonic to Adult Stages of the Brain.

    PubMed

    Nieto-Estévez, Vanesa; Defterali, Çağla; Vicario-Abejón, Carlos

    2016-01-01

    The generation of neurons in the adult mammalian brain requires the activation of quiescent neural stem cells (NSCs). This activation and the sequential steps of neuron formation from NSCs are regulated by a number of stimuli, which include growth factors. Insulin-like growth factor-I (IGF-I) exert pleiotropic effects, regulating multiple cellular processes depending on their concentration, cell type, and the developmental stage of the animal. Although IGF-I expression is relatively high in the embryonic brain its levels drop sharply in the adult brain except in neurogenic regions, i.e., the hippocampus (HP) and the subventricular zone-olfactory bulb (SVZ-OB). By contrast, the expression of IGF-IR remains relatively high in the brain irrespective of the age of the animal. Evidence indicates that IGF-I influences NSC proliferation and differentiation into neurons and glia as well as neuronal maturation including synapse formation. Furthermore, recent studies have shown that IGF-I not only promote adult neurogenesis by regulating NSC number and differentiation but also by influencing neuronal positioning and migration as described during SVZ-OB neurogenesis. In this article we will revise and discuss the actions reported for IGF-I signaling in a variety of in vitro and in vivo models, focusing on the maintenance and proliferation of NSCs/progenitors, neurogenesis, and neuron integration in synaptic circuits. PMID:26941597

  20. HnRNPL as a key factor in spermatogenesis: Lesson from functional proteomic studies of azoospermia patients with sertoli cell only syndrome.

    PubMed

    Li, Jingping; Guo, Wenbin; Li, Fei; He, Jincan; Yu, Qingfeng; Wu, Xiaoqiang; Li, Jianming; Mao, Xiangming

    2012-06-01

    Sertoli cell only syndrome (SCOS) is one of the main causes leading to the abnormal spermatogenesis. However, the mechanisms for abnormal spermatogenesis in SCOS are still unclear. Here, we analyzed the clinical testis samples of SCOS patients by two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF/TOF MS) to find the key factors contributing to SCOS. Thirteen differential proteins were identified in clinical testis samples between normal spermatogenesis group and SCOS group. Interestingly, in these differential proteins, Heterogeneous nuclear ribonucleoprotein L(HnRNPL) was suggested as a key regulator involved in apoptosis, death and growth of spermatogenic cells by String and Pubgene bioinformatic programs. Down-regulated HnRNPL in testis samples of SCOS patients was further confirmed by immunohistochemical staining and western blotting. Moreover, in vitro and in vivo experiments demonstrated that knockdown of HnRNPL led to inhibited proliferation, increased apoptosis of spermatogenic cell but decreased apoptosis of sertoli cells. Expression of carcinoembryonic antigen-related cell adhesion molecule 1 in GC-1 cells or expression of inducible nitric oxide synthases in TM4 sertoli cells, was found to be regulated by HnRNPL. Our study first shows HnRNPL as a key factor involved in the spermatogenesis by functional proteomic studies of azoospermia patients with sertoli cell only syndrome. This article is part of a Special Issue entitled: Proteomics: The clinical link. PMID:22245417

  1. Widespread pain and depression are key modifiable risk factors associated with reduced social participation in older adults

    PubMed Central

    Wilkie, Ross; Blagojevic-Bucknall, Milisa; Belcher, John; Chew-Graham, Carolyn; Lacey, Rosie J.; McBeth, John

    2016-01-01

    Abstract In older adults, reduced social participation increases the risk of poor health-related quality of life, increased levels of inflammatory markers and cardiovascular disease, and increased mortality. Older adults frequently present to primary care, which offers the potential to deliver interventions at the point of care to increase social participation. The aim of this prospective study was to identify the key modifiable exposures that were associated with reduced social participation in a primary care population of older adults. The study was a population-based prospective cohort study. Participants (n = 1991) were those aged ≥65 years who had completed questionnaires at baseline, and 3 and 6-year follow-ups. Generalized linear mixed modeling framework was used to test for associations between exposures and decreasing social participation over 6 years. At baseline, 44% of participants reported reduced social participation, increasing to 49% and 55% at 3 and 6-year follow-up. Widespread pain and depression had the strongest independent association with reduced social participation over the 6-year follow-up period. The prevalence of reduced social participation for those with widespread pain was 106% (adjusted incidence rate ratio 2.06, 95% confidence interval 1.72, 2.46), higher than for those with no pain. Those with depression had an increased prevalence of 82% (adjusted incidence rate ratio 1.82, 95% confidence interval 1.62, 2.06). These associations persisted in multivariate analysis. Population ageing will be accompanied by increasing numbers of older adults with pain and depression. Future trials should assess whether screening for widespread pain and depression, and targeting appropriate treatment in primary care, increase social participation in older people. PMID:27495019

  2. Should I stay or should I go? Eukaryotic translation initiation factors 1 and 1A control start codon recognition.

    PubMed

    Mitchell, Sarah F; Lorsch, Jon R

    2008-10-10

    Start codon selection is a key step in translation initiation as it sets the reading frame for decoding. Two eukaryotic initiation factors, eIF1 and eIF1A, are key actors in this process. Recent work has elucidated many details of the mechanisms these factors use to control start site selection. eIF1 prevents the irreversible GTP hydrolysis that commits the ribosome to initiation at a particular codon. eIF1A both promotes and inhibits commitment through the competing influences of its two unstructured termini. Both factors perform their tasks through a variety of interactions with other components of the initiation machinery, in many cases mediated by the unstructured regions of the two proteins. PMID:18593708

  3. Structure and dynamics of the kinase IKK-β--A key regulator of the NF-kappa B transcription factor.

    PubMed

    Kalia, Munishikha; Kukol, Andreas

    2011-11-01

    The inhibitor κB kinase-β (IKK-β) phosphorylates the NF-κB inhibitor protein IκB leading to the translocation of the transcription factor NF-κB to the nucleus. The transcription factor NF-κB and consequently IKK-β are central to signal transduction pathways of mammalian cells. The purpose of this research was to develop a 3D structural model of the IKK-β kinase domain with its ATP cofactor and investigate its dynamics and ligand binding potential. Through a combination of comparative modelling and simulated heating/annealing molecular dynamics (SAMD) simulation in explicit water the model accuracy could be substantially improved compared to comparative modelling on its own as shown by model validation measures. The structure revealed the details of ATP/Mg(2+) binding indicating hydrophobic interactions with the adenine base and a significant contribution of Mg(2+) as a bridge between ATP phosphate groups and negatively charged side chains. The molecular dynamics trajectories of the ATP-bound and free enzyme showed two conformations in each case, which contributed to the majority of the trajectory. The ATP-free enzyme revealed a novel binding site distant from the ATP binding site that was not encountered in the ATP bound enzyme. Based on the overall structural flexibility, it is suggested that a truncated version of the kinase domain from Ala14 to Leu265 should be subjected to crystallisation trials. The 3D structure of this enzyme will enable rational design of new ligands and analysis of protein-protein interactions. Furthermore, our results may provide a new impetus for wet-lab based structural investigation focussing on a truncated kinase domain. PMID:21820058

  4. Phase detector for three-phase power factor controller

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (Inventor)

    1984-01-01

    A phase detector for the three phase power factor controller (PFC) is described. The phase detector for each phase includes an operational amplifier which senses the current phase angle for that phase by sensing the voltage across the phase thyristor. Common mode rejection is achieved by providing positive feedback between the input and output of the voltage sensing operational amplifier. this feedback preferably comprises a resistor connected between the output and input of the operational amplifier. The novelty of the invention resides in providing positive feedback such that switching of the operational amplifier is synchronized with switching of the voltage across the thyristor. The invention provides a solution to problems associated with high common mode voltage and enables use of lower cost components than would be required by other approaches.

  5. On several factors that control rates of discounting.

    PubMed

    Weatherly, Jeffrey N

    2014-05-01

    Discounting occurs when the subjective value of an outcome decreases because its delivery is either delayed or uncertain. Discounting has been widely studied because of its ubiquitous nature. Research from our laboratory has demonstrated that rates of discounting are systematically altered by several different factors. This paper outlines how the type of data-collection method (i.e., multiple choice vs. fill in the blank), how one frames the outcome being discounted (i.e., won vs. owed), and the type of outcome (i.e., money vs. medical treatment) by magnitude of the outcome (i.e., small vs. large) by type of discounting (i.e., delay vs. probability) interaction can potentially control observed rates of discounting. Such findings should not only be of interest to individuals who study the quantitative analyses of discounting, but also to researchers and theoreticians trying to understand and generalize findings from studies on discounting. PMID:24487030

  6. Human factors studies of control configurations for advanced transport aircraft

    NASA Technical Reports Server (NTRS)

    Snyder, Harry L.; Monty, Robert W.; Old, Joe

    1985-01-01

    This research investigated the threshold levels of display luminance contrast which were required to interpret static, achromatic, integrated displays of primary flight information. A four-factor within-subjects design was used to investigate the influences of type of flight variable information, the level of ambient illumination, the type of control input, and the size of the display symbology on the setting of these interpretability thresholds. A three-alternative forced choice paradigm was used in conjunction with the method of adjustments to obtain a measure of the upper limen of display luminance contrast needed to interpret a complex display of primary flight information. The pattern of results and the absolute magnitudes of the luminance contrast settings were found to be in good agreement with previously reported data from psychophysical investigations of display luminance contrast requirements.

  7. Factors controlling the structures of magma chambers in basaltic volcanoes

    NASA Technical Reports Server (NTRS)

    Wilson, L.; Head, James W.

    1991-01-01

    The depths, vertical extents, and lateral extents of magma chambers and their formation are discussed. The depth to the center of a magma chamber is most probably determined by the density structure of the lithosphere; this process is explained. It is commonly assumed that magma chambers grow until the stress on the roof, floor, and side-wall boundaries exceed the strength of the wall rocks. Attempts to grow further lead to dike propagation events which reduce the stresses below the critical values of rock failure. The tensile or compressive failure of the walls is discussed with respect to magma migration. The later growth of magma chambers is accomplished by lateral dike injection into the country rocks. The factors controlling the patterns of growth and cooling of such dikes are briefly mentioned.

  8. Multiple Sclerosis Associated Risk Factors: A Case-Control Study

    PubMed Central

    POOROLAJAL, Jalal; MAZDEH, Mehrdokht; SAATCHI, Mohammad; TALEBI GHANE, Elaheh; BIDERAFSH, Azam; LOTFI, Bahar; FERYADRES, Mohammad; PAJOHI, Khabat

    2015-01-01

    Background: Hamadan Province is one of the high-risk regions in Iran for Multiple sclerosis (MS). A majority of the epidemiological studies conducted in Iran addressing MS are descriptive. This study was conducted to assess MS and its associated risk factors in Hamadan Province, the west of Iran. Methods: This case-control study compared 100 patients with MS (case group) and 100 patients with acute infectious diseases (control group) from September 2013 to March 2014. A checklist was used to assess the demographic, medical, and family history of the patients. The Friedman-Rosenman questionnaire was also used to assess personality type. Statistical analysis was performed using logistic regression model with Stata 11 software program. Results: The adjusted odds ratio (OR) estimate of MS was 4.37 (95% CI: 2.33, 8.20) for females compared to males; 0.15 (95% CI: 0.06, 0.43) for people aged above 50 years compared to aged 14 to 29 years; 0.44 (95% CI: 0.21, 0.91) for overweight or obese people compared to normal weights. Crude OR indicated a significant association between the occurrence of MS and exclusive breast feeding, season of birth, and smoking. However, the association was not statistically significant after adjustment for other covariates. Conclusion: The risk of MS is significantly lower in male gender, obese/overweight, and old people. Furthermore, non-smoking, non-exclusive breast-feeding, and born in autumn may increase the risk of MS but need further investigation. However, long-term large prospective cohort studies are needed to investigate the true effect of the potential risk factors on MS. PMID:26744707

  9. Secreted frizzled related protein 2 (Sfrp2) is the key Akt-mesenchymal stem cell-released paracrine factor mediating myocardial survival and repair

    PubMed Central

    Mirotsou, Maria; Zhang, Zhongyan; Deb, Arjun; Zhang, Lunan; Gnecchi, Massimiliano; Noiseux, Nicolas; Mu, Hui; Pachori, Alok; Dzau, Victor

    2007-01-01

    Stem cell therapy has emerged as a promising tool for the treatment of a variety of diseases. Previously, we have shown that Akt-modified mesenchymal stem cells mediate tissue repair through paracrine mechanisms. Using a comprehensive functional genomic strategy, we show that secreted frizzled related protein 2 (Sfrp2) is the key stem cell paracrine factor that mediates myocardial survival and repair after ischemic injury. Sfrp2 is known to modulate Wnt signaling, and we demonstrate that cardiomyocytes treated with secreted frizzled related protein increase cellular β-catenin and up-regulate expression of antiapoptotic genes. These findings reveal the key role played by Sfrp2 in mediating the paracrine effects of Akt-mesenchymal stem cells on tissue repair and identify modulation of Wnt signaling as a therapeutic target for heart disease. PMID:17251350

  10. Key Factors for a High-Quality Peritoneal Dialysis Program — The Role of the PD Team and Continuous Quality Improvement

    PubMed Central

    Fang, Wei; Ni, Zhaohui; Qian, Jiaqi

    2014-01-01

    The proportion of end-stage renal disease (ESRD) patients on peritoneal dialysis (PD) has increased very fast in China over the last decade. Renji Hospital, affiliated with Shanghai Jiaotong University School of Medicine, is a recognized high-quality PD unit with a high PD utilization rate, excellent patient and technique survival (1-year and 5-year patient survival rate of 93% and 71%, and 1-year and 5-year technique survival of 96% and 82%, respectively), low peritonitis rate and a well-documented good quality of life of the treated patients. We believe that a dedicated and experienced PD team, a structured patient training program, continuous patient support, establishing and utilizing standardized protocols, starting PD with low dialysis dose, monitoring key performance indicators (KPIs), and continuous quality improvement (CQI) are the key factors underlying this successful PD program. PMID:24962961

  11. Key parameters controlling OH-initiated formation of secondary organic aerosol in the aqueous phase (aqSOA)

    NASA Astrophysics Data System (ADS)

    Ervens, Barbara; Sorooshian, Armin; Lim, Yong B.; Turpin, Barbara J.

    2014-04-01

    Secondary organic aerosol formation in the aqueous phase of cloud droplets and aerosol particles (aqSOA) might contribute substantially to the total SOA burden and help to explain discrepancies between observed and predicted SOA properties. In order to implement aqSOA formation in models, key processes controlling formation within the multiphase system have to be identified. We explore parameters affecting phase transfer and OH(aq)-initiated aqSOA formation as a function of OH(aq) availability. Box model results suggest OH(aq)-limited photochemical aqSOA formation in cloud water even if aqueous OH(aq) sources are present. This limitation manifests itself as an apparent surface dependence of aqSOA formation. We estimate chemical OH(aq) production fluxes, necessary to establish thermodynamic equilibrium between the phases (based on Henry's law constants) for both cloud and aqueous particles. Estimates show that no (currently known) OH(aq) source in cloud water can remove this limitation, whereas in aerosol water, it might be feasible. Ambient organic mass (oxalate) measurements in stratocumulus clouds as a function of cloud drop surface area and liquid water content exhibit trends similar to model results. These findings support the use of parameterizations of cloud-aqSOA using effective droplet radius rather than liquid water volume or drop surface area. Sensitivity studies suggest that future laboratory studies should explore aqSOA yields in multiphase systems as a function of these parameters and at atmospherically relevant OH(aq) levels. Since aerosol-aqSOA formation significantly depends on OH(aq) availability, parameterizations might be less straightforward, and oxidant (OH) sources within aerosol water emerge as one of the major uncertainties in aerosol-aqSOA formation.

  12. Quality control of CT systems by automated monitoring of key performance indicators: a two-year study.

    PubMed

    Nowik, Patrik; Bujila, Robert; Poludniowski, Gavin; Fransson, Annette

    2015-01-01

    The purpose of this study was to develop a method of performing routine periodical quality controls (QC) of CT systems by automatically analyzing key performance indicators (KPIs), obtainable from images of manufacturers' quality assurance (QA) phantoms. A KPI pertains to a measurable or determinable QC parameter that is influenced by other underlying fundamental QC parameters. The established KPIs are based on relationships between existing QC parameters used in the annual testing program of CT scanners at the Karolinska University Hospital in Stockholm, Sweden. The KPIs include positioning, image noise, uniformity, homogeneity, the CT number of water, and the CT number of air. An application (MonitorCT) was developed to automatically evaluate phantom images in terms of the established KPIs. The developed methodology has been used for two years in clinical routine, where CT technologists perform daily scans of the manufacturer's QA phantom and automatically send the images to MonitorCT for KPI evaluation. In the cases where results were out of tolerance, actions could be initiated in less than 10 min. 900 QC scans from two CT scanners have been collected and analyzed over the two-year period that MonitorCT has been active. Two types of errors have been registered in this period: a ring artifact was discovered with the image noise test, and a calibration error was detected multiple times with the CT number test. In both cases, results were outside the tolerances defined for MonitorCT, as well as by the vendor. Automated monitoring of KPIs is a powerful tool that can be used to supplement established QC methodologies. Medical physicists and other professionals concerned with the performance of a CT system will, using such methods, have access to comprehensive data on the current and historical (trend) status of the system such that swift actions can be taken in order to ensure the quality of the CT examinations, patient safety, and minimal disruption of service

  13. Shoreline as a controlling factor in commercial shrimp production

    NASA Technical Reports Server (NTRS)

    Faller, K. H. (Principal Investigator)

    1978-01-01

    An ecological model was developed that relates marsh detritus export and shrimp production, based on the hypothesis that the shoreline is a controlling factor in the production of shrimp through regulation of detritus export from the marsh. LANDSAT data were used to develop measurements of shoreline length and area of marsh having more than 5.0 km shoreline/sq km for the coast of Louisiana, demonstrating the capability of remote sensing to provide important geographic information. These factors were combined with published tidal ranges and salinities to develop a mathematical model that predicted shrimp production for nine geographic units of the Louisiana coast, as indicated by the long term average commercial shrimp yield. The mathematical model relating these parameters and the shrimp production is consistent with an energy flow model describing the interaction of detritus producing marshlands with shrimp nursery grounds and inshore shrimping areas. The analysis supports the basic hypothesis and further raises the possibility of applications to coastal zone management requirements.

  14. Transcription factor PIF4 controls the thermosensory activation of flowering.

    PubMed

    Kumar, S Vinod; Lucyshyn, Doris; Jaeger, Katja E; Alós, Enriqueta; Alvey, Elizabeth; Harberd, Nicholas P; Wigge, Philip A

    2012-04-12

    Plant growth and development are strongly affected by small differences in temperature. Current climate change has already altered global plant phenology and distribution, and projected increases in temperature pose a significant challenge to agriculture. Despite the important role of temperature on plant development, the underlying pathways are unknown. It has previously been shown that thermal acceleration of flowering is dependent on the florigen, FLOWERING LOCUS T (FT). How this occurs is, however, not understood, because the major pathway known to upregulate FT, the photoperiod pathway, is not required for thermal acceleration of flowering. Here we demonstrate a direct mechanism by which increasing temperature causes the bHLH transcription factor PHYTOCHROME INTERACTING FACTOR4 (PIF4) to activate FT. Our findings provide a new understanding of how plants control their timing of reproduction in response to temperature. Flowering time is an important trait in crops as well as affecting the life cycles of pollinator species. A molecular understanding of how temperature affects flowering will be important for mitigating the effects of climate change. PMID:22437497

  15. Factors controlling structural style and magmatism in passive margins

    NASA Astrophysics Data System (ADS)

    Lu, Gang; Huismans, Ritske S.

    2015-04-01

    Comparing volcanic and non-volcanic passive margins, the distinct variability in geometry and subsidence history implies that the thermo-mechanical conditions vary at the time of rifting. Volcanic rifted margins (such as in the North Atlantic) show large magmatic activity and shallow water condition at the rift-drift transition, implying high geothermal gradients. For non-volcanic rifted margins where the initial thermal condition is potentially colder, it may develop in two end-member styles (Type I and Type II). Type-I margin with limited magmatism can be observed at Iberia-Newfoundland conjugate margins where the continental crustal thins across a narrow region and large tracts of continental mantle lithosphere are exposed at the seafloor. Type-II margin as observed in the ultra-wide central South Atlantic margins, in contrast, has normal magmatic activity and has a strongly thinned continental crust that span very wide regions (>250 km) below which the continental mantle lithosphere was removed. Here we perform thermo-mechanical finite element numerical experiments to investigate factors that are potentially important for the formation of volcanic and non-volcanic passive margins. Forward numerical models are used to predict the structural styles and characteristic magmatism associated with each of these end members. A number of parameters including different rheological stratifications and thermal gradients are tested and factors that control the degree of magmatism and structural style during rifting are focused.

  16. Where does the water table outcrop? Analysis of controlling factors across scales

    NASA Astrophysics Data System (ADS)

    Bresciani, E.; Batelaan, O.

    2014-12-01

    The water table 'roughly' follows the topography. 'Roughly', because the water table intercepts the topography only in a few locations, such as along the gaining portions of streams and other surface discharge features, including drains, wetlands, seeps and the coastline. Elsewhere, the water table occurs below the land surface and is therefore controlled by recharge and hydraulic conductivity. Hence, the control of the topography on the water table arises through the occurrence of water table outcrops. This study analyses water table outcrops as a function of climatic, geologic and topographic factors in theoretical configurations, based on numerical simulations. The water table is treated as a free surface, whose position adapts to the parameters. The studied system is dimensionless and serves as a first-order approximation model for any scale. Varying the amplitude and frequency of topographic undulations, as well as recharge and hydraulic conductivity, relationships between key controlling factors and water table outcrops are investigated. The results provide fundamental understanding of water table shapes, and so of groundwater flow, under various conditions and without assuming the water table to be identical to the topography. Because water table outcrops also indicates areas of groundwater discharge and of interaction of groundwater with surface water, groundwater-dependent ecosystems and the atmosphere, the results have implications that go far beyond the scope of groundwater flow characterization. This includes the conceptualisation and modelling of stream baseflow, wetlands, riparian areas and water and energy exchanges between groundwater and the atmosphere.

  17. Autophagy Gene Activity May Act As a Key Factor for Sensitivity of Tumor Cells to Oncolytic Vesicular Stomatitis Virus

    PubMed Central

    Nabizadeh, Arezoo; Bamdad, Taravat; Arefian, Ehsan; Razavi Nikoo, Seyed Hadi

    2016-01-01

    Background: Beclin1 is an important, primary molecule for autophagy. Objectives: It is suggested that the control of the autophagy path increases the sensitivity of tumor cells to VSV. Materials and Methods: In this study, the degree of Beclin1 gene expression in two cell lines, HeLa and A549, has been examined and the percentage of living cells subsequent infection with virus has been evaluated by MTT assay method. Results: The results showed that the degree of Beclin1 gene expression in HeLa cells in comparison with A549 cells has reduced, and the sensitivity of these cells to vesicular stomatits virus (VSV) oncolysis is more than A549. Conclusions: It seems that by using some methods for reducing autophagy, it is possible to make tumor cells more sensitive to virotherapy and even other treatments. PMID:27366311

  18. Transcriptome Analysis of Sexually Dimorphic Chinese White Wax Scale Insects Reveals Key Differences in Developmental Programs and Transcription Factor Expression

    PubMed Central

    Yang, Pu; Chen, Xiao-Ming; Liu, Wei-Wei; Feng, Ying; Sun, Tao

    2015-01-01

    The Chinese white wax scale insect, Ericerus pela, represents one of the most dramatic examples of sexual dimorphism in any insect species. In this study, we showed that although E. pela males display complete metamorphosis similar to holometabolous insects, the species forms the sister group to Acyrthosiphon pisum and cluster with hemimetabolous insects. The gene expression profile and Gene Ontology (GO) analyses revealed that the two sexes engaged in distinct developmental programs. In particular, female development appeared to prioritize the expression of genes related to cellular, metabolic, and developmental processes and to anatomical structure formation in nymphs. By contrast, male nymphal development is characterized by the significant down-regulation of genes involved in chitin, the respiratory system, and neurons. The wing and appendage morphogenesis, anatomical and tissue structure morphogenesis programs activated after male nymphal development. Transcription factors (that convey juvenile hormone or ecdysone signals, and Hox genes) and DNA methyltransferase were also differentially expressed between females and males. These results may indicate the roles that these differentially expressed genes play in regulating sexual dimorphism through orchestrating complex genetic programs. This differential expression was particularly prominent for processes linked to female development and wing development in males. PMID:25634031

  19. Transcriptome analysis of sexually dimorphic Chinese white wax scale insects reveals key differences in developmental programs and transcription factor expression.

    PubMed

    Yang, Pu; Chen, Xiao-Ming; Liu, Wei-Wei; Feng, Ying; Sun, Tao

    2015-01-01

    The Chinese white wax scale insect, Ericerus pela, represents one of the most dramatic examples of sexual dimorphism in any insect species. In this study, we showed that although E. pela males display complete metamorphosis similar to holometabolous insects, the species forms the sister group to Acyrthosiphon pisum and cluster with hemimetabolous insects. The gene expression profile and Gene Ontology (GO) analyses revealed that the two sexes engaged in distinct developmental programs. In particular, female development appeared to prioritize the expression of genes related to cellular, metabolic, and developmental processes and to anatomical structure formation in nymphs. By contrast, male nymphal development is characterized by the significant down-regulation of genes involved in chitin, the respiratory system, and neurons. The wing and appendage morphogenesis, anatomical and tissue structure morphogenesis programs activated after male nymphal development. Transcription factors (that convey juvenile hormone or ecdysone signals, and Hox genes) and DNA methyltransferase were also differentially expressed between females and males. These results may indicate the roles that these differentially expressed genes play in regulating sexual dimorphism through orchestrating complex genetic programs. This differential expression was particularly prominent for processes linked to female development and wing development in males. PMID:25634031

  20. Searching for a Role of Nursing Personnel in Developing Landscape of Ehealth: Factors Determining Attitudes toward Key Patient Empowering Applications

    PubMed Central

    Duplaga, Mariusz

    2016-01-01

    Introduction Nurses may play an important role in the delivery of medical services based on the use of ehealth tools. Nevertheless, their taking an active role in an ehealth environment depends on their possessing the appropriate skills and mindset. The main objective of this paper was to assess nurses’ opinions and to analyze the predictors of their acceptance of ehealth features relevant to patient empowerment with a strong focus on chronic care. Methods A survey was conducted among nurses from hospital centers of south-eastern Poland based on a questionnaire designed to assess their attitudes toward the ehealth domain. The predictors of the nurses’ acceptance of ehealth usage within specific contexts were assessed with uni- and multivariate logistic regression. Results An analysis was performed on data from 648 questionnaires retained after a quality check. The duration of Internet use was consistently related to higher acceptance of ehealth applications and more certainty regarding the reliability of health-related information available on the Internet. Nurses from urban medical centers were more skeptical about the use of specific ehealth solutions. Conclusion Previous experience in using information technologies is the main factor influencing the acceptance of specific ehealth solutions relevant for care provided to patients suffering from chronic conditions. PMID:27049525

  1. Glucocorticoid-Induced Tumour Necrosis Factor Receptor-Related Protein: A Key Marker of Functional Regulatory T Cells

    PubMed Central

    Ronchetti, Simona; Ricci, Erika; Petrillo, Maria Grazia; Cari, Luigi; Migliorati, Graziella; Nocentini, Giuseppe; Riccardi, Carlo

    2015-01-01

    Glucocorticoid-induced tumour necrosis factor receptor-related protein (GITR, TNFRSF18, and CD357) is expressed at high levels in activated T cells and regulatory T cells (Tregs). In this review, we present data from mouse and human studies suggesting that GITR is a crucial player in the differentiation of thymic Tregs (tTregs), and expansion of both tTregs and peripheral Tregs (pTregs). The role of GITR in Treg expansion is confirmed by the association of GITR expression with markers of memory T cells. In this context, it is not surprising that GITR appears to be a marker of active Tregs, as suggested by the association of GITR expression with other markers of Treg activation or cytokines with suppressive activity (e.g., IL-10 and TGF-β), the presence of GITR+ cells in tissues where Tregs are active (e.g., solid tumours), or functional studies on Tregs. Furthermore, some Treg subsets including Tr1 cells express either low or no classical Treg markers (e.g., FoxP3 and CD25) and do express GITR. Therefore, when evaluating changes in the number of Tregs in human diseases, GITR expression must be evaluated. Moreover, GITR should be considered as a marker for isolating Tregs. PMID:25961057

  2. Validation of revised DNDC model for methane emissions from irrigated rice fields in Thailand and sensitivity analysis of key factors

    NASA Astrophysics Data System (ADS)

    Smakgahn, Kruamas; Fumoto, Tamon; Yagi, Kazuyuki

    2009-06-01

    The original Denitrification-Decomposition (DNDC) model and a revised version were tested against data from field observations of methane (CH4) emissions from irrigated rice fields in Thailand. The revised DNDC model, which was modified for use in Japanese rice fields by revising the crop growth and soil biogeochemical submodels, yielded better simulation results than the original model. In most cases, daily CH4 fluxes predicted by the revised DNDC model agreed well with observations. Seasonal CH4 emissions simulated by the revised model showed significantly higher correlation with observations than those obtained with the original model. Errors in the simulation appear to have resulted from uncertainties in both the input parameters and the model descriptions. Sensitivity analysis revealed that the revised DNDC model is highly sensitive to the concentration of reducible soil Fe, the rate of rice straw incorporation, and rice root biomass. Therefore, uncertainties in these factors may strongly affect the prediction of CH4 emissions. These results suggest that for reliable prediction of CH4 emissions from Thai rice fields, further work is needed to improve the estimates of reducible soil Fe, to quantify the rate of straw incorporation, and to parameterize the crop submodel for the dominant rice varieties grown in Thailand.

  3. Tannin is a key factor in the determination and prediction of energy content in sorghum grains fed to growing pigs.

    PubMed

    Pan, L; Li, P; Ma, X K; Xu, Y T; Tian, Q Y; Liu, L; Li, D F; Piao, X S

    2016-07-01

    DE and 3,973 - (262 × % tannin) - (27.24 × % ADF) for ME. Our results strongly indicate that the DE and ME content of sorghum grains are related to their chemical composition, especially their tannin content. The DE and ME content could decrease by more than 200 kcal/kg when the tannin content is increased by 1% in the sorghum grain. Overall, tannin is a key predictor for the DE and ME content as well as the ATTD of GE in sorghum grains, and the potent antinutritive properties from tannin should not be ignored when sorghum is used as an energy source for pigs. PMID:27482674

  4. Factors Controlling Nitrogen Fluxes in Groundwater in Agricultural Areas

    NASA Astrophysics Data System (ADS)

    Liao, L.; Green, C. T.; Bekins, B. A.; Bohlke, J. K.

    2010-12-01

    Predictions of effects of land use changes on water quality require identification of the relative importance of geochemical and hydrologic factors. To understand the factors controlling the transport of nitrogen in groundwater, vertical fluxes of water and solutes were estimated for 13 aquifers in agricultural areas located in California, Iowa, Maryland, Minnesota, Mississippi, Nebraska, North Carolina, Texas, and Wisconsin. The aquifers are overlain by unsaturated zones with thicknesses ranging from 2.5 to 100 m. Precipitation ranges from 19 to 132 cm/yr and irrigation ranges from 0 to 120 cm/yr. Main crop types include corn, soybeans, forage, wheat, and cotton. A 1-dimensional mathematical model was developed to estimate vertical N transport in response to N inputs on the land surface from chemical fertilizer, manure and atmospheric deposition. Simulated vertical profiles of O2, NO3-, N2 from denitrification, Cl- and atmospheric age tracers were matched to observations by adjusting parameters for recharge rate, unsaturated zone travel time, N leaching ratio (defined as leaching fraction of N reaching water table of N input at land surface), Cl- leaching ratio, O2 reduction rate and denitrification rate. Results indicated that vertical NO3 fluxes below the water table were affected by both geochemical and physical factors. High vertical NO3 fluxes below the water table are associated with high N input at the land surface. Values of Cl- leaching ratios were less than 1 (0.42 to 1) likely as a result of runoff and exported harvested crops. N leaching ratios were lower (0.1 to 0.6), consistent with additional N losses such as denitrification and volatilization. The sites with high leaching ratios for both N and Cl tended to be those with high recharge rates and low ET loss, defined as the fraction of applied water lost to ET. Modeled zero-order denitrification rates in the saturated zone varied within an order of magnitude with a maximum rate of 1.6 mg

  5. The Cytosolic pH of Individual Saccharomyces cerevisiae Cells Is a Key Factor in Acetic Acid Tolerance

    PubMed Central

    Fernández-Niño, Miguel; Marquina, Maribel; Swinnen, Steve; Rodríguez-Porrata, Boris

    2015-01-01

    It was shown recently that individual cells of an isogenic Saccharomyces cerevisiae population show variability in acetic acid tolerance, and this variability affects the quantitative manifestation of the trait at the population level. In the current study, we investigated whether cell-to-cell variability in acetic acid tolerance could be explained by the observed differences in the cytosolic pHs of individual cells immediately before exposure to the acid. Results obtained with cells of the strain CEN.PK113-7D in synthetic medium containing 96 mM acetic acid (pH 4.5) showed a direct correlation between the initial cytosolic pH and the cytosolic pH drop after exposure to the acid. Moreover, only cells with a low initial cytosolic pH, which experienced a less severe drop in cytosolic pH, were able to proliferate. A similar correlation between initial cytosolic pH and cytosolic pH drop was also observed in the more acid-tolerant strain MUCL 11987-9. Interestingly, a fraction of cells in the MUCL 11987-9 population showed initial cytosolic pH values below the minimal cytosolic pH detected in cells of the strain CEN.PK113-7D; consequently, these cells experienced less severe drops in cytosolic pH. Although this might explain in part the difference between the two strains with regard to the number of cells that resumed proliferation, it was observed that all cells from strain MUCL 11987-9 were able to proliferate, independently of their initial cytosolic pH. Therefore, other factors must also be involved in the greater ability of MUCL 11987-9 cells to endure strong drops in cytosolic pH. PMID:26341199

  6. Stature and jumping height are required in female volleyball, but motor coordination is a key factor for future elite success.

    PubMed

    Pion, Johan A; Fransen, Job; Deprez, Dieter N; Segers, Veerle I; Vaeyens, Roel; Philippaerts, Renaat M; Lenoir, Matthieu

    2015-06-01

    It was hypothesized that differences in anthropometry, physical performance, and motor coordination would be found between Belgian elite and sub-elite level female volleyball players using a retrospective analysis of test results gathered over a 5-year period. The test sample in this study consisted of 21 young female volleyball players (15.3 ± 1.5 years) who were selected to train at the Flemish Top Sports Academy for Volleyball in 2008. All players (elite, n = 13; sub-elite, n = 8) were included in the same talent development program, and the elite-level athletes were of a high to very high performance levels according to European competition level in 2013. Five multivariate analyses of variance were used. There was no significant effect of playing level on measures of anthropometry (F = 0.455, p = 0.718, (Equation is included in full-text article.)= 0.07), flexibility (F = 1.861, p = 0.188, (Equation is included in full-text article.)= 0.19), strength (F = 1.218, p = 0.355, (Equation is included in full-text article.)= 0.32); and speed and agility (F = 1.176, p = 0.350, (Equation is included in full-text article.)= 0.18). Multivariate analyses of variance revealed significant multivariate effects between playing levels for motor coordination (F = 3.470, p = 0.036, (Equation is included in full-text article.)= 0.59). A Mann-Whitney U test and a sequential discriminant analysis confirmed these results. Previous research revealed that stature and jump height are prerequisites for talent identification in female volleyball. In addition, the results show that motor coordination is an important factor in determining inclusion into the elite level in female volleyball. PMID:25436627

  7. Nitrous oxide emissions from intensive agricultural systems: Variations between crops and seasons, key driving variables, and mean emission factors

    NASA Astrophysics Data System (ADS)

    Dobbie, K. E.; McTaggart, I. P.; Smith, K. A.

    1999-11-01

    Emissions of nitrous oxide from intensively managed agricultural fields were measured over 3 years. Exponential increases in flux occurred with increasing soil water- filled pore space (WFPS) and temperature; increases in soil mineral N content due to fertilizer application also stimulated emissions. Fluxes were low when any of these variables was below a critical value. The largest fluxes occurred when WFPS values were very high (70-90%), indicating that denitrification was the major process responsible. The relationships with the driving variables showed strong similarities to those reported for very different environments: irrigated sugar cane crops, pastures, and forest in the tropics. Annual emissions varied widely (0.3-18.4 kg N2O-N ha-1). These variations were principally due to the degree of coincidence of fertilizer application and major rainfall events. It is concluded therefore that several years' data are required from any agricultural ecosystem in a variable climate to obtain a robust estimate of mean N2O fluxes. The emissions from small-grain cereals (winter wheat and spring barley) were consistently lower (0.2-0.7 kg N2O-N per 100 kg N applied) than from cut grassland (0.3-5.8 kg N2O- N per 100 kg N). Crops such as broccoli and potatoes gave emissions of the same order as those from the grassland. Although these differences between crop types are not apparent in general data comparisons, there may well be distinct regional differences in the relative and absolute emissions from different crops, due to local factors relating to soil type, weather patterns, and agricultural management practices. This will only be determined by more detailed comparative studies.

  8. Statistical study to identify the key factors governing ground water recharge in the watersheds of the arid Central Asia.

    PubMed

    Zhu, Binq-Qi; Wang, Yue-Ling

    2016-01-01

    Understanding the source and recharge of ground waters is of great significance to our knowledge in hydrological cycles in arid environments over the world. Northern Xinjiang in northwestern China is a significant repository of information relating to the hydrological evolution and climatic changes in central Asia. In this study, two multivariate statistical techniques, hierarchical cluster analysis (HCA) and principal component analysis (PCA), were used to assess the ground water recharge and its governing factors, with the principal idea of exploring the above techniques to utilize all available hydrogeochemical variables in the quality assessment, which are not considered in the conventional techniques like Stiff and Piper diagrams. Q-mode HCA and R-mode PCA were combined to partition the water samples into seven major water clusters (C1-C7) and three principal components (PC1-PC3, PC1 salinity, PC2 hydroclimate, PC3 contaminant). The water samples C1 + C4 were classified as recharge area waters (Ca-HCO3 water), C2 + C3 as transitional zone waters (Ca-Mg-HCO3-SO4 water), and C5 + C6 + C7 as discharge area waters (Na-SO4 water). Based on the Q-mode PCA scores, three groups of geochemical processes influencing recharge regimes were identified: geogenic (i.e., caused by natural geochemical processes), geomorphoclimatic (caused by topography and climate), and anthropogenic (caused by ground water contamination). It is proposed that differences in recharge mechanism and ground water evolution, and possible bedrock composition difference, are responsible for the chemical genesis of these waters. These will continue to influence the geochemistry of the northern Xinjiang drainage system for a long time due to its steady tectonics and arid climate. This study proved that the chemistry differentiation of ground water can effectively support the identification of ground water recharge and evolution patterns. PMID:26718947

  9. Emerging and Reemerging Neglected Tropical Diseases: a Review of Key Characteristics, Risk Factors, and the Policy and Innovation Environment

    PubMed Central

    Liang, Bryan A.; Cuomo, Raphael; Hafen, Ryan; Brouwer, Kimberly C.; Lee, Daniel E.

    2014-01-01

    SUMMARY In global health, critical challenges have arisen from infectious diseases, including the emergence and reemergence of old and new infectious diseases. Emergence and reemergence are accelerated by rapid human development, including numerous changes in demographics, populations, and the environment. This has also led to zoonoses in the changing human-animal ecosystem, which are impacted by a growing globalized society where pathogens do not recognize geopolitical borders. Within this context, neglected tropical infectious diseases have historically lacked adequate attention in international public health efforts, leading to insufficient prevention and treatment options. This subset of 17 infectious tropical diseases disproportionately impacts the world's poorest, represents a significant and underappreciated global disease burden, and is a major barrier to development efforts to alleviate poverty and improve human health. Neglected tropical diseases that are also categorized as emerging or reemerging infectious diseases are an even more serious threat and have not been adequately examined or discussed in terms of their unique risk characteristics. This review sets out to identify emerging and reemerging neglected tropical diseases and explore the policy and innovation environment that could hamper or enable control efforts. Through this examination, we hope to raise awareness and guide potential approaches to addressing this global health concern. PMID:25278579

  10. Advanced environmental control as a key component in the development of ultrahigh accuracy ex situ metrology for x-ray optics

    NASA Astrophysics Data System (ADS)

    Yashchuk, Valeriy V.; Artemiev, Nikolay A.; Lacey, Ian; McKinney, Wayne R.; Padmore, Howard A.

    2015-10-01

    The advent of fully coherent free-electron laser and diffraction-limited synchrotron radiation storage ring sources of x-rays is catalyzing the development of new ultrahigh accuracy metrology methods. To fully exploit these sources, metrology needs to be capable of determining the figure of an optical element with subnanometer height accuracy. The major limiting factors of the current absolute accuracy of ex situ metrology are drift errors due to temporal instabilities of the lab's environmental conditions and systematic errors inherent to the metrology instruments. Here, we discuss in detail work at the Advanced Light Source X-Ray Optics Laboratory on building of advanced environmental control that is a key component in the development of ultrahigh accuracy ex situ metrology for x-ray optics. By a few examples, we show how the improvement of the environmental conditions in the lab allows us to significantly gain efficiency in performing ex situ metrology with high-quality x-ray mirrors. The developed concepts and approaches, included in the design of the new X-Ray Optics Laboratory, are described in detail. These data are essential for construction and successful operation of a modern metrology facility for x-ray optics, as well as high-precision measurements in many fields of experimental physics.

  11. DYNAMIC CHANGES IN COLORED DISSOLVED ORGANIC MATTER AND TOTAL SUSPENDED MATTER CONTROL UV EXPOSURE OF CORAL REEFS IN THE FLORIDA KEYS

    EPA Science Inventory

    Variation in ultraviolet (UV) light exposure is one important environmental factor that influences the health of coral reefs. Here we present evidence that the reef tract in the Florida Keys experiences significantly higher variability in UV exposure than other surrounding coast...

  12. The Microglial α7-Acetylcholine Nicotinic Receptor Is a Key Element in Promoting Neuroprotection by Inducing Heme Oxygenase-1 via Nuclear Factor Erythroid-2-Related Factor 2

    PubMed Central

    Parada, Esther; Egea, Javier; Buendia, Izaskun; Negredo, Pilar; Cunha, Ana C.; Cardoso, Silvia; Soares, Miguel P.

    2013-01-01

    Abstract Aims: We asked whether the neuroprotective effect of cholinergic microglial stimulation during an ischemic event acts via a mechanism involving the activation of nuclear factor erythroid-2-related factor 2 (Nrf2) and/or the expression of its target cytoprotective gene, heme oxygenase-1 (HO-1). Specifically, the protective effect of the pharmacologic alpha-7 nicotinic acetylcholine receptor (α7 nAChR) agonist PNU282987 was analyzed in organotypic hippocampal cultures (OHCs) subjected to oxygen and glucose deprivation (OGD) in vitro as well as in photothrombotic stroke in vivo. Results: OHCs exposed to OGD followed by reoxygenation elicited cell death, measured by propidium iodide and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide staining. Activation of α7 nAChR by PNU282987, after OGD, reduced cell death, reactive oxygen species production, and tumor necrosis factor release. This was associated with induction of HO-1 expression, an effect reversed by α-bungarotoxin and by tin–protoporphyrin IX. The protective effect of PNU282987 was lost in microglial-depleted OHCs as well as in OHCs from Nrf2-deficient-versus-wild-type mice, an effect associated with suppression of HO-1 expression in microglia. Administration of PNU282987 1 h after induction of photothrombotic stroke in vivo reduced the infarct size and improved motor skills in Hmox1lox/lox mice that express normal levels of HO-1, but not in LysMCreHmox1Δ/Δ in which HO-1 expression is inhibited in myeloid cells, including the microglia. Innovation: This study suggests the participation of the microglial α7 nAChR in the brain cholinergic anti-inflammatory pathway. Conclusion: Activation of the α7 nAChR/Nrf2/HO-1 axis in microglia regulates neuroinflammation and oxidative stress, affording neuroprotection under brain ischemic conditions. Antioxid. Redox Signal. 19, 1135–1148. PMID:23311871

  13. Suicide in young adults: psychiatric and socio-economic factors from a case–control study

    PubMed Central

    2014-01-01

    Background Suicide in young adults remains an important public health issue in Australia. The attributable risks associated with broader socioeconomic factors, compared to more proximal psychiatric disorders, have not been considered previously in individual-level studies of young adults. This study compared the relative contributions of psychiatric disorder and socio-economic disadvantage associated with suicide in terms of relative and attributable risk in young adults. Method A population-based case–control study of young adults (18–34 years) compared cases of suicide (n = 84) with randomly selected controls (n = 250) from population catchments in New South Wales (Australia), with exposure information collected from key informant interviews (for both cases and controls). The relative and attributable risk of suicide associated with ICD-10 defined substance use, affective, and anxiety disorder was compared with educational achievement and household income, adjusting for key confounders. Prevalence of exposures from the control group was used to estimate population attributable fractions (PAF). Results Strong associations were evident between mental disorders and suicide for both males and females (ORs 3.1 to 18.7). The strongest association was for anxiety disorders (both males and females), followed by affective disorders and substance use disorders. Associations for socio-economic status were smaller in magnitude than for mental disorders for both males and females (ORs 1.1 to 4.8 for lower compared to high SES groups). The combined PAF% for all mental disorders (48% for males and 52% for females) was similar in magnitude to socio-economic status (46% for males and 58% for females). Conclusion Socio-economic status had a similar magnitude of population attributable risk for suicide as mental disorders. Public health interventions to reduce suicide should incorporate socio-economic disadvantage in addition to mental illness as a potential target for

  14. The role of biogenic, biomass burning and urban pollution aerosol particles in controlling key atmospheric processes in Amazonia

    NASA Astrophysics Data System (ADS)

    Artaxo, P.; Ferreira De Brito, J.; Barbosa, H. M.; Rizzo, L. V.; Sena, E. T.; Cirino, G.; Arana, A.; Yanez-Serrano, A. M.

    2013-05-01

    As part of the LBA (The Large Scale Biosphere Atmosphere Experiment in Amazonia) experiment, a research program run in the last 10 years had help to understand critical atmospheric processes in Amazonia. The vegetation in Amazonia is a direct source of aerosol particles to the atmosphere as well as a source of biogenic trace gases that generates particles trough gas-to-particle conversion. Biomass burning is also a large source of particles and trace gases to the atmosphere. Over the last 10 years, the LBA experiment has unveiled several key processes that control Amazonian composition and influence regional climate. A significant fraction (60-80%) of airborne particles can act as Cloud Condensation Nuclei (CCN), influencing cloud formation and development. The radiation balance is strongly influenced by biomass burning particles, and surface radiative forcing up to -250 w/m2 is measured. A network of 8 sites with AERONET sunphotometers measures aerosol optical depth (AOD) and derive aerosol size distribution and optical properties. Aerosols are composed of more than 70% of organic material, with significant absorption characteristics. The aerosol radiative forcing during the biomass burning season can reach very high values, and the increase in diffuse radiation increases the carbon uptake by the forest for AOD values smaller than 1.2 at 500nm. For large AOD, the solar flux is strongly reduced making the carbon uptake approach zero for AOD larger than 3.0. The composition of aerosols is mostly organic, with contribution of K, Ca, Si, and other trace elements. The aerosol has high capability to serve as Cloud Condensation Nuclei (CCN), contributing with high water vapor amounts to the significant cloud cover over the region. In the last 20 years, an urbanization process took over for most of the Amazonian region, increasing urban pollution that interacts with forest emissions to produce a quite unique pattern of aerosols and pollutants around large urban areas such

  15. Hydrologic factors controlling groundwater salinity in northwestern coastal zone, Egypt

    NASA Astrophysics Data System (ADS)

    Morad, Nahla A.; Masoud, M. H.; Moghith, S. M. Abdel

    2014-10-01

    The aim of this article is to assess the main factors influencing salinity of groundwater in the coastal area between El Dabaa and Sidi Barani, Egypt. The types and ages of the main aquifers in this area are the fractured limestone of Middle Miocene, the calcareous sandstone of Pliocene and the Oolitic Limestone of Pleistocene age. The aquifers in the area are recharged by seasonal rainfall of the order of 150 mm/year. The relationship of groundwater salinity against the absolute water level, the well drilling depth, and the ability of aquifer to recharge has been discussed in the present work. The ability of aquifer to locally recharge by direct rainfall is a measure of the vertical permeability due to lithological and structural factors that control groundwater salinity in the investigated aquifers. On the other hand, the fracturing system as well as the attitude of the surface water divide has a prime role in changing both the mode of occurrence and the salinity of groundwater in the area. Directly to the west of Matrouh, where the coastal plain is the narrowest, and east of Barrani, where the coastal plain is the widest, are good examples of this concept, where the water salinity attains its maximum and minimum limits respectively. Accordingly, well drilling in the Miocene aquifer, in the area between El Negila and Barrani to get groundwater of salinities less than 5000 mg/l is recommended in this area, at flow rate less than 10 m3/hr/well. In other words, one can expect that the brackish water is probably found where the surface water divide is far from the shore line, where the Wadi fill deposits dominate (Quaternary aquifer), acting as a possible water salinity by direct rainfall and runoff.

  16. The Expression of BAFF Is Controlled by IRF Transcription Factors.

    PubMed

    Sjöstrand, Maria; Johansson, Alina; Aqrawi, Lara; Olsson, Tomas; Wahren-Herlenius, Marie; Espinosa, Alexander

    2016-01-01

    Patients with systemic lupus erythematosus (SLE) and primary Sjögren's syndrome (pSS) are typically characterized by the presence of autoantibodies and an IFN-signature. The strength of the IFN-signature positively correlates with disease severity, suggesting that type I IFNs are active players in these diseases. BAFF is a cytokine critical for development and proper selection of B cells, and the targeting of BAFF has emerged as a successful treatment strategy of SLE. Previous reports have suggested that BAFF expression is directly induced by type I IFNs, but the precise mechanism for this remains unknown. In this article, we demonstrate that BAFF is a bona fide ISG and that IFN regulatory factors (IRFs) control the expression of BAFF. We identify IRF1 and IRF2 as positive regulators of BAFF transcription and IRF4 and IRF8 as potent repressors; in addition, we have mapped the precise binding site for these factors in the BAFF promoter. IFN-β injections induced BAFF expression mainly in neutrophils and monocytes, and BAFF expression in neutrophils from pSS patients strongly correlated with the strength of the IFN-signature. In summary, we show that BAFF expression is directly induced by type I IFNs via IRF1 and IRF2, whereas IRF4 and IRF8 are negative regulators of BAFF expression. These data suggest that type I IFN blockade in SLE and pSS patients will lead to downregulation of BAFF and a consequential reduction of autoreactive B cell clones and autoantibodies. PMID:26590315

  17. The Expression of BAFF Is Controlled by IRF Transcription Factors

    PubMed Central

    Sjöstrand, Maria; Johansson, Alina; Aqrawi, Lara; Olsson, Tomas; Wahren-Herlenius, Marie

    2016-01-01

    Patients with systemic lupus erythematosus (SLE) and primary Sjögren’s syndrome (pSS) are typically characterized by the presence of autoantibodies and an IFN-signature. The strength of the IFN-signature positively correlates with disease severity, suggesting that type I IFNs are active players in these diseases. BAFF is a cytokine critical for development and proper selection of B cells, and the targeting of BAFF has emerged as a successful treatment strategy of SLE. Previous reports have suggested that BAFF expression is directly induced by type I IFNs, but the precise mechanism for this remains unknown. In this article, we demonstrate that BAFF is a bona fide ISG and that IFN regulatory factors (IRFs) control the expression of BAFF. We identify IRF1 and IRF2 as positive regulators of BAFF transcription and IRF4 and IRF8 as potent repressors; in addition, we have mapped the precise binding site for these factors in the BAFF promoter. IFN-β injections induced BAFF expression mainly in neutrophils and monocytes, and BAFF expression in neutrophils from pSS patients strongly correlated with the strength of the IFN-signature. In summary, we show that BAFF expression is directly induced by type I IFNs via IRF1 and IRF2, whereas IRF4 and IRF8 are negative regulators of BAFF expression. These data suggest that type I IFN blockade in SLE and pSS patients will lead to downregulation of BAFF and a consequential reduction of autoreactive B cell clones and autoantibodies. PMID:26590315

  18. Heat-Shock Factor 1 Controls Genome-wide Acetylation in Heat-shocked Cells

    PubMed Central

    Fritah, Sabrina; Col, Edwige; Boyault, Cyril; Govin, Jérôme; Sadoul, Karin; Chiocca, Susanna; Christians, Elisabeth; Khochbin, Saadi; Jolly, Caroline

    2009-01-01

    A major regulatory function has been evidenced here for HSF1, the key transcription factor of the heat-shock response, in a large-scale remodeling of the cell epigenome. Indeed, upon heat shock, HSF1, in addition to its well-known transactivating activities, mediates a genome-wide and massive histone deacetylation. Investigating the underlying mechanisms, we show that HSF1 specifically associates with and uses HDAC1 and HDAC2 to trigger this heat-shock–dependent histone deacetylation. This work therefore identifies HSF1 as a master regulator of global chromatin acetylation and reveals a cross-talk between HSF1 and histone deacetylases in the general control of genome organization in response to heat shock. PMID:19793920

  19. Short-term selective alleviation of glucotoxicity and lipotoxicity ameliorates the suppressed expression of key β-cell factors under diabetic conditions.

    PubMed

    Shimo, Naoki; Matsuoka, Taka-aki; Miyatsuka, Takeshi; Takebe, Satomi; Tochino, Yoshihiro; Takahara, Mitsuyoshi; Kaneto, Hideaki; Shimomura, Iichiro

    2015-11-27

    Alleviation of hyperglycaemia and hyperlipidemia improves pancreatic β-cell function in type 2 diabetes. However, the underlying molecular mechanisms are still not well clarified. In this study, we aimed to elucidate how the expression alterations of key β-cell factors are altered by the short-term selective alleviation of glucotoxicity or lipotoxicity. We treated db/db mice for one week with empagliflozin and/or bezafibrate to alleviate glucotoxicity and/or liptotoxicity, respectively. The gene expression levels of Pdx1 and Mafa, and their potential targets, insulin 1, Slc2a2, and Glp1r, were higher in the islets of empagliflozin-treated mice, and levels of insulin 2 were higher in mice treated with both reagents, than in untreated mice. Moreover, compared to the pretreatment levels, Mafa and insulin 1 expression increased in empagliflozin-treated mice, and Slc2a2 increased in combination-treated mice. In addition, empagliflozin treatment enhanced β-cell proliferation assessed by Ki-67 immunostaining. Our date clearly demonstrated that the one-week selective alleviation of glucotoxicity led to the better expression levels of the key β-cell factors critical for β-cell function over pretreatment levels, and that the alleviation of lipotoxicity along with glucotoxicity augmented the favorable effects under diabetic conditions. PMID:26471305

  20. Transcription Factor ATAF1 in Arabidopsis Promotes Senescence by Direct Regulation of Key Chloroplast Maintenance and Senescence Transcriptional Cascades1[OPEN

    PubMed Central

    Garapati, Prashanth; Xue, Gang-Ping

    2015-01-01

    Senescence represents a fundamental process of late leaf development. Transcription factors (TFs) play an important role for expression reprogramming during senescence; however, the gene regulatory networks through which they exert their functions, and their physiological integration, are still largely unknown. Here, we identify the Arabidopsis (Arabidopsis thaliana) abscisic acid (ABA)- and hydrogen peroxide-activated TF Arabidopsis thaliana ACTIVATING FACTOR1 (ATAF1) as a novel upstream regulator of senescence. ATAF1 executes its physiological role by affecting both key chloroplast maintenance and senescence-promoting TFs, namely GOLDEN2-LIKE1 (GLK1) and ORESARA1 (ARABIDOPSIS NAC092), respectively. Notably, while ATAF1 activates ORESARA1, it represses GLK1 expression by directly binding to their promoters, thereby generating a transcriptional output that shifts the physiological balance toward the progression of senescence. We furthermore demonstrate a key role of ATAF1 for ABA- and hydrogen peroxide-induced senescence, in accordance with a direct regulatory effect on ABA homeostasis genes, including NINE-CIS-EPOXYCAROTENOID DIOXYGENASE3 involved in ABA biosynthesis and ABC TRANSPORTER G FAMILY MEMBER40, encoding an ABA transport protein. Thus, ATAF1 serves as a core transcriptional activator of senescence by coupling stress-related signaling with photosynthesis- and senescence-related transcriptional cascades. PMID:25953103

  1. Factors controlling pathogen destruction during anaerobic digestion of biowastes

    SciTech Connect

    Smith, S.R. . E-mail: s.r.smith@imperial.ac.uk; Lang, N.L.; Cheung, K.H.M.; Spanoudaki, K.

    2005-07-01

    Anaerobic digestion is the principal method of stabilising biosolids from urban wastewater treatment in the UK, and it also has application for the treatment of other types of biowaste. Increasing awareness of the potential risks to human and animal health from environmental sources of pathogens has focused attention on the efficacy of waste treatment processes at destroying pathogenic microorganisms in biowastes recycled to agricultural land. The degree of disinfection achieved by a particular anaerobic digester is influenced by a variety of interacting operational variables and conditions, which can often deviate from the ideal. Experimental investigations demonstrate that Escherichia coli and Salmonella spp. are not damaged by mesophilic temperatures, whereas rapid inactivation occurs by thermophilic digestion. A hydraulic, biokinetic and thermodynamic model of pathogen inactivation during anaerobic digestion showed that a 2 log{sub 10} reduction in E. coli (the minimum removal required for agricultural use of conventionally treated biosolids) is likely to challenge most conventional mesophilic digesters, unless strict maintenance and management practices are adopted to minimise dead zones and by-pass flow. Efficient mixing and organic matter stabilisation are the main factors controlling the rate of inactivation under mesophilic conditions and not a direct effect of temperature per se on pathogenic organisms.

  2. Factors controlling ebro deep-sea fan growth, Mediterranean Sea

    SciTech Connect

    Nelson, C.H.; Maldonado, A.; Alonso, B.; Palanques, A.; Ryan, W.B.F.; Kastens, K.; O'Connel, S.

    1985-01-01

    Tectonic, sediment-source and sea-level factors control depositional patterns of the Ebro deep-sea fan system. In unstable, steep continental slope terrain, mass movement of material results in wide gullied canyons and formation of non-channelized debris aprons. These fan channels develop low sinuosity and generally traverse the continental rise without feeding into depositional lobes because of steep gradients (1:50 to 1:100) and sediment draining into the subsiding Valencia Valley graben. An abundance of sediment input points from mass failure and many river-fed canyons contributes to a depositional pattern of side-by-side debris aprons and separate channel-levee complexes. When a large sediment supply feeds a channel for a relatively long period 1) fan valley sinuosity increases: 2) channel walls are modified through undercutting, slumping, and crevasse splays: 3) channel bifurcation occurs: 4) incipient depositional lobe formation begins. Lowering of sea levels in Late Pleistocene time permitted the access of coarse river sediment to slope valleys and promoted deposition of numerous turbidites and active growth of the fan. During the Holocene, when sea levels have been high, a regime of hemipelagic sedimentation, mass movement, and debris apron sedimentation has dominated.

  3. Interacting factors in the control of the crustacean molt cycle

    SciTech Connect

    Skinner, D.M.

    1983-01-01

    In order to account for the known phenomena of the crustacean molt cycle, at least six factors must be postulated: a molting hormone (20-OH-ecdysone), a molt inhibiting hormone (MIH), an anecdysial limb autotomy factor, a proecdysial limb autotomy factor, a limb growth inhibiting factor and an exuviation factor. Only the molting hormone and its derivatives have been chemically well defined. The various factors interact in complex ways to maintain not only a coordinated proecdysial period in preparation for exuviation but also a proecdysial period with the flexibility to respond to such interim hazards as the loss of partially regenerated limbs. 78 references, 2 figures, 1 table.

  4. Interacting factors in the control of the crustacean molt cycle

    SciTech Connect

    Skinner, D.M.

    1985-01-01

    In order to account for the known phenomena of the crustacean molt cycle, at least six factors must be postulated: a molting hormone (20-OH-ecdysone), a molt-inhibiting hormone (MIH), an anecdysial limb autotomy factor, a proecdysial limb-autotomy factor, a limb growth-inhibiting factor and an exuviation factor. Only the molting hormone and its derivatives have been chemically well defined. The various factors interact in complex ways to maintain not only a coordinated proecdysial period in preparation for exuviation but also a proecdysial period with the flexibility to respond to such interim hazards as the loss of partially regenerated limbs. 79 references, 2 figures, 1 table.

  5. Predicting alcohol consumption in adolescence from alcohol-specific and general externalizing genetic risk factors, key environmental exposures and their interaction

    PubMed Central

    Kendler, K. S.; Gardner, C.; Dick, D. M.

    2011-01-01

    Background Alcohol consumption is influenced by specific genetic risk factors for alcohol use disorders (AUDs), non-specific genetic risk factors for externalizing behaviors and various environmental experiences. We have limited knowledge of how these risk factors inter-relate through development. Method Retrospective assessments in 1796 adult male twins using a life history calendar of key environmental exposures and alcohol consumption from early adolescence to mid-adulthood. Analysis by linear mixed models. Results The importance of non-specific genetic risk factors on maximal alcohol consumption rose rapidly in early to mid-adolescence, peaked at ages 15–17 years and then declined slowly. Alcohol-specific genetic risk factors increased slowly in influence through mid-adulthood. We detected robust evidence for environmental moderation of genetic effects on alcohol consumption that was more pronounced in early and mid-adolescence than in later periods. Alcohol availability, peer deviance and low prosocial behaviors showing the strongest moderation effects. More interactions with environmental risk factors were seen for the non-specific externalizing disorder risk than for specific genetic risk for AUDs. Conclusions The impact of specific and non-specific genetic influences on alcohol consumption have different development trajectories. Genetic effects on alcohol use are more pronounced when social constraints are minimized (e.g. low prosocial behaviors or parental monitoring) or when the environment permits easy access to alcohol and/or encourages its use (e.g. high alcohol availability or peer deviance). Gene–environment interactions influencing alcohol intake may be more robust at younger ages, indicating greater plasticity of genetic influences early in the development of drinking patterns. PMID:20942993

  6. Taking control over control: use of product sensing in single cells to remove flux control at key enzymes in biosynthesis pathways.

    PubMed

    Schendzielorz, Georg; Dippong, Martin; Grünberger, Alexander; Kohlheyer, Dietrich; Yoshida, Ayako; Binder, Stephan; Nishiyama, Chiharu; Nishiyama, Makoto; Bott, Michael; Eggeling, Lothar

    2014-01-17

    Enzymes initiating the biosynthesis of cellular building blocks are frequently inhibited by the end-product of the respective pathway. Here we present an approach to rapidly generate sets of enzymes overriding this control. It is based on the in vivo detection of the desired end-product in single cells using a genetically encoded sensor. The sensor transmits intracellular product concentrations into a graded optical output, thus enabling ultrahigh-throughput screens by FACS. We randomly mutagenized plasmid-encoded ArgB of Corynebacterium glutamicum and screened the library in a strain carrying the sensor pSenLys-Spc, which detects l-lysine, l-arginine and l-histidine. Six of the resulting N-acetyl-l-glutamate kinase proteins were further developed and characterized and found to be at least 20-fold less sensitive toward l-arginine inhibition than the wild-type enzyme. Overexpression of the mutein ArgB-K47H-V65A in C. glutamicumΔargR led to the accumulation of 34 mM l-arginine in the culture medium. We also screened mutant libraries of lysC-encoded aspartate kinase and hisG-encoded ATP phosphoribosyltransferase. We isolated 11 LysC muteins, enabling up to 45 mM l-lysine accumulation, and 13 HisG muteins, enabling up to 17 mM l-histidine accumulation. These results demonstrate that in vivo screening of enzyme libraries by using metabolite sensors is extremely well suited to identify high-performance muteins required for overproduction. PMID:23829416

  7. A key time point for cell growth and magnetosome synthesis of Magnetospirillum gryphiswaldense based on real-time analysis of physiological factors

    PubMed Central

    Yang, Jing; Li, Shuqi; Huang, Xiuliang; Tang, Tao; Jiang, Weizhong; Zhang, Tongwei; Li, Ying

    2013-01-01

    Pure culture of magnetotactic bacteria with high magnetosome yield has been achieved for only a few strains. The major obstacles involve the nutritional requirements and culture conditions of the cells. To increase cell density and magnetosome production, it is necessary to elucidate the physiological characteristics of a particular strain during cell growth and develop an appropriate artificial control strategy. Large-scale culture of Magnetospirillum gryphiswaldense strain MSR-1 was successfully performed for 48 h in a 42-L autofermentor, and several key physiological parameters were measured in real time. Maximal values of cell density (OD565) (19.4) and cell yield (dry weight) (4.76 g/L) were attained at 40 h. The key time point for cell growth and magnetosome formation was found to be 18–20 h. At this point, cells entered the log phase of growth, the maximal values of Cmag (1.78), iron content (0.47%), and magnetosome number (26 ± 3 per cell) were observed, superoxide dismutase (SOD) activity began to decrease more rapidly, ATP content dropped to an extremely low level (0.17 fmol), and reducing power (NADH/NAD+ ratio) began to increase very rapidly. Excessive levels of dissolved oxygen (≥20 ppb) and lactic acid in the medium caused notable cytotoxic effects after 20 h. Artificial control measures for fermentation must be based on realistic cell physiological conditions. At the key time point (18–20 h), cell density is high and magnetosomes have matured. The process of magnetosome synthesis involves a high consumption of ATP and reducing power, and the cells require replenishment of nutrients prior to the 18–20 h time point. Culture conditions that effectively minimize dissolved oxygen accumulation, lactic acid content, and reducing power at this point will enhance magnetosome yield without obvious inhibition of cell growth. PMID:23898327

  8. Understanding Mathematics: Some Key Factors

    ERIC Educational Resources Information Center

    Ali, Asma Amanat; Reid, Norman

    2012-01-01

    Mathematics is well known as a subject area where there can be problems in terms of understanding as well as retaining positive attitudes. In a large study involving 813 school students (ages approximately 10-12) drawn from two different school systems in Pakistan, the effect of limited working memory capacity on performance in mathematics was…

  9. Regional trends and controlling factors of fatal landslides in Latin America and the Caribbean

    NASA Astrophysics Data System (ADS)

    Sepúlveda, S. A.; Petley, D. N.

    2015-08-01

    A new data set of landslides that caused loss of life in Latin America and the Caribbean in the 10-year period from 2004 and 2013 inclusive has been compiled, providing new insight into the impact of landslides in this key part of the world. This data set indicates that in the 10-year period a total of 11 631 people lost their lives across the region in 611 landslides. The geographical distribution of the landslides is highly heterogeneous, with areas of high incidence in parts of the Caribbean (most notably Haiti), Central America, Colombia, and southeast Brazil. There is significant interannual variation in the number of landslides, with the El Niño/La Niña cycle emerging as a key control. Our analysis suggests that on a continental scale the mapped factors that best explain the observed distribution are topography, annual precipitation and population density. On a national basis we have compared the occurrence of fatality-inducing landslide occurrence with the production of locally authored research articles, demonstrating that there is a landslide research deficit in Latin America and the Caribbean. Understanding better the mechanisms, distribution causes and triggers of landslides in Latin America and the Caribbean must be an essential first step towards managing the hazard.

  10. How to identify the key factors that affect driver perception of accident risk. A comparison between Italian and Spanish driver behavior.

    PubMed

    de Oña, Juan; de Oña, Rocio; Eboli, Laura; Forciniti, Carmen; Mazzulla, Gabriella

    2014-12-01

    Road crashes can be caused by different factors, including infrastructure, vehicles, and human variables. Many research studies have focused solely on identifying the key factors that cause road crashes. From these studies, it emerged that human factors have the most relevant impact on accident severity. More specifically, accident severity depends on several factors related directly to the driver, i.e., driving experience, driver's socio-economic characteristics, and driving behavior and attitudes. In this paper, we investigate driver behaviors and attitudes while driving and specifically focus on different methods for identifying the factors that most affect the driver's perception of accident risk. To this end, we designed and conducted a survey in two different European contexts: the city of Cosenza, which is located in the south of Italy, and the city of Granada, which is located in the south of Spain. Samples of drivers were contacted for their opinions on certain aspects of driving rules and attitudes while driving, and different types of questions were addressed to the drivers to assess their judgments of these aspects. Consequently, different methods of data analysis were applied to determine the aspects that heavily influence driver perception of accident risk. An experiment based on the stated preferences (SP) was carried out with the drivers, and the SP data were analyzed using an ordered probit (OP) model. Interesting findings emerged from different analyses of the data and from the comparisons among the data collected in the two different territorial contexts. We found that both Italian and Spanish drivers consider driving in an altered psychophysical state and violating the overtaking rules to be the most risky behaviors. PMID:25247553

  11. Improving Control of Antibiotic-Resistant Gonorrhea by Integrating Research Agendas Across Disciplines: Key Questions Arising From Mathematical Modeling.

    PubMed

    Grad, Yonatan H; Goldstein, Edward; Lipsitch, Marc; White, Peter J

    2016-03-15

    The rise in gonococcal antibiotic resistance and the threat of untreatable infection are focusing attention on strategies to limit the spread of drug-resistant gonorrhea. Mathematical models provide a framework to link the natural history of infection and patient behavior to epidemiological outcomes and can be used to guide research and enhance the public health impact of interventions. While limited knowledge of key disease parameters and networks of spread has impeded development of operational models of gonococcal transmission, new tools in gonococcal surveillance may provide useful data to aid tracking and modeling. Here, we highlight critical questions in the management of gonorrhea that can be addressed by mathematical models and identify key data needs. Our overarching aim is to articulate a shared agenda across gonococcus-related fields from microbiology to epidemiology that will catalyze a comprehensive evidence-based clinical and public health strategy for management of gonococcal infections and antimicrobial resistance. PMID:26518045

  12. Hypothalamic control of the pituitary-gonadal axis in higher primates: key advances over the last two decades.

    PubMed

    Plant, T M

    2008-06-01

    This review provides a brief historical background to the foundation of primate reproductive neuroendocrinology that was laid by Ernst Knobil during the late 1960s and early 1970s. This is followed by a discussion of studies conducted over the last two decades that I view as having contributed to the current understanding of the field of primate reproductive neuroendocrinology. The review concludes with a short summary of key questions that remain to be addressed. PMID:18601694

  13. Calcitonin gene-related peptide is a key factor in the homing of transplanted human MSCs to sites of spinal cord injury.

    PubMed

    Zhang, Yu; Yang, Jinhua; Zhang, Peng; Liu, Tao; Xu, Jianwei; Fan, Zhihai; Shen, Yixin; Li, Wenjie; Zhang, Huanxiang

    2016-01-01

    Mesenchymal stem cells (MSCs) can be used to treat many diseases, including spinal cord injury (SCI). Treatment relies mostly on the precise navigation of cells to the injury site for rebuilding the damaged spinal cord. However, the key factors guiding MSCs to the epicenter of SCI remain unknown. Here, we demonstrated that calcitonin gene-related peptide (CGRP), a neural peptide synthesized in spinal cord, can dramatically aid the homing of human umbilical cord mesenchymal stem cells (HUMSCs) in spinal cord-transected SCI rats. First, HUMSCs exhibited chemotactic responses in vitro to CGRP. By time-lapse video analysis, increased chemotactic index (CMI), forward migration index (FMI) and speed contributed to this observed migration. Then, through enzyme immunoassay, higher CGRP concentrations at the lesion site were observed after injury. The release of CGRP directed HUMSCs to the injury site, which was suppressed by CGRP 8-37, a CGRP antagonist. We also verified that the PI3K/Akt and p38MAPK signaling pathways played a critical role in the CGRP-induced chemotactic migration of HUMSCs. Collectively, our data reveal that CGRP is a key chemokine that helps HUMSCs migrate to the lesion site and thereby can be used as a model molecule to study MSCs homing after SCI. PMID:27296555

  14. Calcitonin gene-related peptide is a key factor in the homing of transplanted human MSCs to sites of spinal cord injury

    PubMed Central

    Zhang, Yu; Yang, Jinhua; Zhang, Peng; Liu, Tao; Xu, Jianwei; Fan, Zhihai; Shen, Yixin; Li, Wenjie; Zhang, Huanxiang

    2016-01-01

    Mesenchymal stem cells (MSCs) can be used to treat many diseases, including spinal cord injury (SCI). Treatment relies mostly on the precise navigation of cells to the injury site for rebuilding the damaged spinal cord. However, the key factors guiding MSCs to the epicenter of SCI remain unknown. Here, we demonstrated that calcitonin gene-related peptide (CGRP), a neural peptide synthesized in spinal cord, can dramatically aid the homing of human umbilical cord mesenchymal stem cells (HUMSCs) in spinal cord-transected SCI rats. First, HUMSCs exhibited chemotactic responses in vitro to CGRP. By time-lapse video analysis, increased chemotactic index (CMI), forward migration index (FMI) and speed contributed to this observed migration. Then, through enzyme immunoassay, higher CGRP concentrations at the lesion site were observed after injury. The release of CGRP directed HUMSCs to the injury site, which was suppressed by CGRP 8–37, a CGRP antagonist. We also verified that the PI3K/Akt and p38MAPK signaling pathways played a critical role in the CGRP-induced chemotactic migration of HUMSCs. Collectively, our data reveal that CGRP is a key chemokine that helps HUMSCs migrate to the lesion site and thereby can be used as a model molecule to study MSCs homing after SCI. PMID:27296555

  15. Florida Keys

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Florida Keys are a chain of islands, islets and reefs extending from Virginia Key to the Dry Tortugas for about 309 kilometers (192 miles). The keys are chiefly limestone and coral formations. The larger islands of the group are Key West (with its airport), Key Largo, Sugarloaf Key, and Boca Chica Key. A causeway extends from the mainland to Key West.

    This image was acquired on October 28, 2001, by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

    Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U.S. Science team leader; Bjorn Eng of JPL is the project manager. The Terra mission is part of NASA's Earth Science Enterprise, a long- term research effort to understand and protect our home planet. Through the study of Earth, NASA will help to provide sound science to policy and economic

  16. Viral infections as controlling factors for the deep biosphere? (Invited)

    NASA Astrophysics Data System (ADS)

    Engelen, B.; Engelhardt, T.; Sahlberg, M.; Cypionka, H.

    2009-12-01

    The marine deep biosphere represents the largest biotope on Earth. Throughout the last years, we have obtained interesting insights into its microbial community composition. However, one component that was completely overlooked so far is the viral inventory of deep-subsurface sediments. While viral infections were identified to have a major impact on the benthic microflora of deep-sea surface sediments (Danavaro et al. 2008), no studies were performed on deep-biosphere samples, so far. As grazers probably play only a minor role in anoxic and highly compressed deep sediments, viruses might be the main “predators” for indigenous microorganisms. Furthermore, the release of cell components, called “the viral shunt”, could have a major impact on the deep biosphere in providing labile organic compounds to non-infected microorganisms in these generally nutrient depleted sediments. However, direct counting of viruses in sediments is highly challenging due to the small size of viruses and the high background of small particles. Even molecular surveys using “universal” PCR primers that target phage-specific genes fail due to the vast phage diversity. One solution for this problem is the lysogenic viral life cycle as many bacteriophages integrate their DNA into the host genome. It is estimated that up to 70% of cultivated bacteria contain prophages within their genome. Therefore, culture collections (Batzke et al. 2007) represent an archive of the viral composition within the respective habitat. These prophages can be induced to become free phage particles in stimulation experiments in which the host cells are set under certain stress situations such as a treatment with UV exposure or DNA-damaging antibiotics. The study of the viral component within the deep biosphere offers to answer the following questions: To which extent are deep-biosphere populations controlled by viral infections? What is the inter- and intra-specific diversity and the host-specific viral

  17. Factors controlling the initiation of Snowball Earth events

    NASA Astrophysics Data System (ADS)

    Voigt, A.

    2012-12-01

    During the Neoproterozoic glaciations tropical continents were covered by active glaciers that extended down to sea level. To explain these glaciers, the Snowball Earth hypothesis assumes that oceans were completely sea-ice covered during these glaciation, but there is an ongoing debate whether or not some regions of the tropical oceans remained open. In this talk, I will describe past and ongoing climate modelling activities with the comprehensive coupled climate model ECHAM5/MPI-OM that identify and compare factors that control the initiation of Snowball Earth events. I first show that shifting the continents from their present-day location to their Marinoan (635 My BP) low-latitude location increases the planetary albedo, cools the climate, and thereby allows Snowball Earth initiation at higher levels of total solar irradiance and atmospheric CO2. I then present simulations with successively lowered bare sea-ice albedo, disabled sea-ice dynamics, and switched-off ocean heat transport. These simulations show that both lowering the bare sea-ice albedo and disabling sea-ice dynamics increase the critical sea-ice cover in ECHAM5/MPI-OM, but sea-ice dynamics due to strong equatorward sea-ice transport have a much larger influence on the critical CO2. Disabling sea-ice transport allows a state with sea-ice margin at 10 deg latitude by virtue of the Jormungand mechanism. The accumulation of snow on land, in combination with tropical land temperatures below or close to freezing, suggests that tropical land glaciers could easily form in such a state. However, in contrast to aquaplanet simulations without ocean heat transport, there is no sign of a Jormungand hysteresis in the coupled simulations. Ocean heat transport is not responsible for the lack of a Jormungand hysteresis in the coupled simulations. By relating the above findings to previous studies, I will outline promising future avenues of research on the initiation of Snowball Earth events. In particular, an

  18. Locus of Control, Self-Efficacy, and Motivation in Different Schools: Is Moderation the Key to Success?

    ERIC Educational Resources Information Center

    Anderson, Angelika; Hattie, John; Hamilton, Richard J.

    2005-01-01

    This study used a novel multidimensional locus of control instrument (I-SEE) to investigate the relationship between locus of control, motivation, and academic achievement in three different types of school. The strengths of the I-SEE are that it incorporates the construct of self-efficacy and that it is embedded in a model of personality and…

  19. Coordinate Control of Muscle Cell Survival by Distinct Insulin-like Growth Factor Activated Signaling Pathways

    PubMed Central

    Lawlor, Margaret A.; Rotwein, Peter

    2000-01-01

    Peptide growth factors control diverse cellular functions by regulating distinct signal transduction pathways. In cultured myoblasts, insulin-like growth factors (IGFs) stimulate differentiation and promote hypertrophy. IGFs also maintain muscle cell viability. We previously described C2 skeletal muscle lines lacking expression of IGF-II. These cells did not differentiate, but underwent progressive apoptotic death when incubated in differentiation medium. Viability could be sustained and differentiation enabled by IGF analogues that activated the IGF-I receptor; survival was dependent on stimulation of phosphatidylinositol 3-kinase (PI3-kinase). We now find that IGF action promotes myoblast survival through two distinguishable PI3-kinase–regulated pathways that culminate in expression of the cyclin-dependent kinase inhibitor, p21. Incubation with IGF-I or transfection with active PI3-kinase led to rapid induction of MyoD and p21, and forced expression of either protein maintained viability in the absence of growth factors. Ectopic expression of MyoD induced p21, and inhibition of p21 blocked MyoD-mediated survival, thus defining one PI3-kinase–dependent pathway as leading first to MyoD, and then to p21 and survival. Unexpectedly, loss of MyoD expression did not impede IGF-mediated survival, revealing a second pathway involving activation by PI3-kinase of Akt, and subsequent induction of p21. Since inhibition of p21 caused death even in the presence of IGF-I, these results establish a central role for p21 as a survival factor for muscle cells. Our observations also define a MyoD-independent pathway for regulating p21 in muscle, and demonstrate that distinct mechanisms help ensure appropriate expression of this key protein during differentiation. PMID:11121430

  20. Lifestyle factors and reproductive health: taking control of your fertility

    PubMed Central

    2013-01-01

    Approximately 10 to 15% of couples are impacted by infertility. Recently, the pivotal role that lifestyle factors play in the development of infertility has generated a considerable amount of interest. Lifestyle factors are the modifiable habits and ways of life that can greatly influence overall health and well-being, including fertility. Many lifestyle factors such as the age at which to start a family, nutrition, weight, exercise, psychological stress, environmental and occupational exposures, and others can have substantial effects on fertility; lifestyle factors such as cigarette smoking, illicit drug use, and alcohol and caffeine consumption can negatively influence fertility while others such as preventative care may be beneficial. The present literature review encompasses multiple lifestyle factors and places infertility in context for the couple by focusing on both males and females; it aims to identify the roles that lifestyle factors play in determining reproductive status. The growing interest and amount of research in this field have made it evident that lifestyle factors have a significant impact on fertility. PMID:23870423

  1. Key Nutrients.

    ERIC Educational Resources Information Center

    Federal Extension Service (USDA), Washington, DC.

    Lessons written to help trainer agents prepare aides for work with families in the Food and Nutrition Program are presented in this booklet. The key nutrients discussed in the 10 lessons are protein, carbohydrates, fat, calcium, iron, iodine, and Vitamins A, B, C, and D. the format of each lesson is as follows: Purpose, Presentation, Application…

  2. Overexpression of Meloe Gene in Melanomas Is Controlled Both by Specific Transcription Factors and Hypomethylation

    PubMed Central

    Bobinet, Mathilde; Vignard, Virginie; Florenceau, Laetitia; Lang, Francois

    2013-01-01

    The melanoma antigens MELOE-1 and MELOE-2 are encoded by a messenger, called meloe, overexpressed in melanomas compared with other tumour cell types and healthy tissues. They are both able to elicit melanoma-specific T cell responses in melanoma patients, and MELOE-1-specific CD8 T cells have been involved in melanoma immunosurveillance. With the aim to develop immunotherapies targeting this antigen, we investigated the transcriptional mechanisms leading to the preferential expression of meloe messenger in the melanocytic lineage. We defined the minimal promoter region of meloe gene and identified binding motifs for a set of transcription factors. Using mutagenesis, co-transfection experiments and chromatin immunoprecipitation, we showed that transcription factors involved in meloe promoter activity in melanomas were the melanocytic specific SOX9 and SOX10 proteins together with the activated P-CREB protein. Furthermore, we showed that meloe promoter was hypomethylated in melanomas and melanocytes, and hypermethylated in colon cancer cell lines and mesotheliomas, thus explaining the absence of P-CREB binding in these cell lines. This was a second key to explain the overerexpression of meloe messenger in the melanocytic lineage. To our knowledge, such a dual transcriptional control conferring tissue-specificity has never been described for the expression of tumour antigens. PMID:24086527

  3. Higher Order Factor Structure of a Self-Control Test: Evidence from Confirmatory Factor Analysis with Polychoric Correlations.

    ERIC Educational Resources Information Center

    Flora, David B.; Finkel, Eli J.; Foshee, Vangie A.

    2003-01-01

    Studied the higher order factor structure of a self-control test developed by H. Grasmick and others (1993). Results for 1,966 eighth and ninth graders show that the self-control test may provide more valid measurement of the constructs it was designed to measure than previous research suggested. (SLD)

  4. Factors controlling floc settling velocity along a longitudinal estuarine transect

    USGS Publications Warehouse

    Manning, A.J.; Schoellhamer, D.H.

    2013-01-01

    A 147 km longitudinal transect of flocculated cohesive sediment properties in San Francisco Bay (SFB) was conducted on June 17th, 2008. Our aim was to determine the factors that control floc settling velocity along the longitudinal axis of the estuary. The INSSEV-LF video system was used to measure floc diameters and settling velocities at 30 stations at a distance of 0.7 m above the estuary bed. Floc sizes (D) ranged from 22 μm to 639 μm and settling velocities (Ws) ranged between 0.04 mm·s− 1 and 15.8 mm·s− 1 during the longitudinal transect. Nearbed turbulent shear stresses throughout the transect duration were within the 0.2–0.5 Pa range which typically stimulates flocculation growth. The individual D–Ws–floc density plots suggest the suspended sediments encountered throughout SFB were composed of both muddy cohesive sediment and mixed sediments flocs. Mass-weighted population mean settling velocity (Wsmass) ranged from 0.5 mm·s− 1 to 10 mm·s− 1. The macrofloc and microfloc (demarcation at 160 μm) sub-populations demonstrated parameterised settling velocities which spanned nearly double the range of the sample mean settling velocities (Wsmean). The macroflocs tended to dominate the suspended mass (up to 77% of the ambient suspended solid concentration; SSC) from San Pablo Bay to Carquinez Strait (the vicinity of the turbidity maximum zone). Microfloc mass was particularly significant (typically 60–100% of the SSC) in the northern section of South Bay and most of Central Bay. The transect took eleven hours to complete and was not fully synoptic. During slack tide, larger and faster settling flocs deposited, accounting for most of the longitudinal variability. The best single predictor of settling velocity was water velocity 39 min prior to sampling, not suspended-sediment concentration or salinity. Resuspension and settling lags are likely responsible for the lagged response of settling velocity to water velocity. The distribution of

  5. Plant-wide distributed control is the key to an efficient waste wood fuel system at Augusta Newsprint

    SciTech Connect

    King, B.; Rennie, C.

    1986-03-01

    Augusta Newsprint has successfully implemented a total plant system almost eliminating the use of fossil fuels in their industrial steam generator whose design, control system and wood waste handling system is described here.

  6. Factor Structure of Children's Locus of Control Beliefs: A Cross-Cultural Approach.

    ERIC Educational Resources Information Center

    Barling, Julian

    1980-01-01

    Nowicki characterized children's locus of control beliefs in terms of three factors: helplessness, luck, and achievement. This study investigated whether these factors are sufficiently consistent or invariant to be used in further analyses. (Author/DB)

  7. The hypoxia factor Hif-1α controls neural crest chemotaxis and epithelial to mesenchymal transition

    PubMed Central

    Barriga, Elias H.; Maxwell, Patrick H.

    2013-01-01

    One of the most important mechanisms that promotes metastasis is the stabilization of Hif-1 (hypoxia-inducible transcription factor 1). We decided to test whether Hif-1α also was required for early embryonic development. We focused our attention on the development of the neural crest, a highly migratory embryonic cell population whose behavior has been likened to cancer metastasis. Inhibition of Hif-1α by antisense morpholinos in Xenopus laevis or zebrafish embryos led to complete inhibition of neural crest migration. We show that Hif-1α controls the expression of Twist, which in turn represses E-cadherin during epithelial to mesenchymal transition (EMT) of neural crest cells. Thus, Hif-1α allows cells to initiate migration by promoting the release of cell–cell adhesions. Additionally, Hif-1α controls chemotaxis toward the chemokine SDF-1 by regulating expression of its receptor Cxcr4. Our results point to Hif-1α as a novel and key regulator that integrates EMT and chemotaxis during migration of neural crest cells. PMID:23712262

  8. Other Factors That Affect Heart Disease: Birth Control Pills

    MedlinePlus

    ... you are now taking any kind of birth control pill or are considering using one, keep these guidelines in mind: Don't mix smoking and "the pill." If you smoke cigarettes, make a serious effort to quit. If you cannot quit, choose ... of birth control. Cigarette smoking boosts the risk of serious health ...

  9. Factors That Affect Patient Attitudes toward Infection Control Measures.

    ERIC Educational Resources Information Center

    Jones, Daniel J.; And Others

    1991-01-01

    A study investigated patient attitudes toward different disease control measures taken in dental school clinics (n=272 patients) and private practices (n=107 patients). Variables examined included sex, age, educational background, and knowledge of infectious diseases. Patients tended to accept the control measures being used in each context. (MSE)

  10. [Research advances in the controlled release of growth factor related to blood vessel tissue engineering].

    PubMed

    Wu, Lili; Yuan, Xiaoyan; Yao, Kangde

    2006-08-01

    Growth factors play an important role in cell adhesion and proliferation as well as in tissue regeneration. By incorporating growth factors into polymer scaffolds, controlled release of them can be performed. The release mechanism is varied with the incorporation methods. In this paper, the latest advances in the controlled release of growth factors by blending, hydrogel, microsphere embedding and chemical bonding are reviewed. The potential application of ultrafine fibric embedding in growth factor delivery is described as well. PMID:17002137

  11. MYB-FL controls gain and loss of floral UV absorbance, a key trait affecting pollinator preference and reproductive isolation.

    PubMed

    Sheehan, Hester; Moser, Michel; Klahre, Ulrich; Esfeld, Korinna; Dell'Olivo, Alexandre; Mandel, Therese; Metzger, Sabine; Vandenbussche, Michiel; Freitas, Loreta; Kuhlemeier, Cris

    2016-02-01

    Adaptations to new pollinators involve multiple floral traits, each requiring coordinated changes in multiple genes. Despite this genetic complexity, shifts in pollination syndromes have happened frequently during angiosperm evolution. Here we study the genetic basis of floral UV absorbance, a key trait for attracting nocturnal pollinators. In Petunia, mutations in a single gene, MYB-FL, explain two transitions in UV absorbance. A gain of UV absorbance in the transition from bee to moth pollination was determined by a cis-regulatory mutation, whereas a frameshift mutation caused subsequent loss of UV absorbance during the transition from moth to hummingbird pollination. The functional differences in MYB-FL provide insight into the process of speciation and clarify phylogenetic relationships between nascent species. PMID:26656847

  12. Flight control system design factors for applying automated testing techniques

    NASA Technical Reports Server (NTRS)

    Sitz, Joel R.; Vernon, Todd H.

    1990-01-01

    Automated validation of flight-critical embedded systems is being done at ARC Dryden Flight Research Facility. The automated testing techniques are being used to perform closed-loop validation of man-rated flight control systems. The principal design features and operational experiences of the X-29 forward-swept-wing aircraft and F-18 High Alpha Research Vehicle (HARV) automated test systems are discussed. Operationally applying automated testing techniques has accentuated flight control system features that either help or hinder the application of these techniques. The paper also discusses flight control system features which foster the use of automated testing techniques.

  13. Paenibacillus larvae Chitin-Degrading Protein PlCBP49 Is a Key Virulence Factor in American Foulbrood of Honey Bees

    PubMed Central

    Garcia-Gonzalez, Eva; Poppinga, Lena; Fünfhaus, Anne; Hertlein, Gillian; Hedtke, Kati; Jakubowska, Agata; Genersch, Elke

    2014-01-01

    Paenibacillus larvae, the etiological agent of the globally occurring epizootic American Foulbrood (AFB) of honey bees, causes intestinal infections in honey bee larvae which develop into systemic infections inevitably leading to larval death. Massive brood mortality might eventually lead to collapse of the entire colony. Molecular mechanisms of host-microbe interactions in this system and of differences in virulence between P. larvae genotypes are poorly understood. Recently, it was demonstrated that the degradation of the peritrophic matrix lining the midgut epithelium is a key step in pathogenesis of P. larvae infections. Here, we present the isolation and identification of PlCBP49, a modular, chitin-degrading protein of P. larvae and demonstrate that this enzyme is crucial for the degradation of the larval peritrophic matrix during infection. PlCBP49 contains a module belonging to the auxiliary activity 10 (AA10, formerly CBM33) family of lytic polysaccharide monooxygenases (LPMOs) which are able to degrade recalcitrant polysaccharides. Using chitin-affinity purified PlCBP49, we provide evidence that PlCBP49 degrades chitin via a metal ion-dependent, oxidative mechanism, as already described for members of the AA10 family. Using P. larvae mutants lacking PlCBP49 expression, we analyzed in vivo biological functions of PlCBP49. In the absence of PlCBP49 expression, peritrophic matrix degradation was markedly reduced and P. larvae virulence was nearly abolished. This indicated that PlCBP49 is a key virulence factor for the species P. larvae. The identification of the functional role of PlCBP49 in AFB pathogenesis broadens our understanding of this important family of chitin-binding and -degrading proteins, especially in those bacteria that can also act as entomopathogens. PMID:25080221

  14. Paenibacillus larvae chitin-degrading protein PlCBP49 is a key virulence factor in American Foulbrood of honey bees.

    PubMed

    Garcia-Gonzalez, Eva; Poppinga, Lena; Fünfhaus, Anne; Hertlein, Gillian; Hedtke, Kati; Jakubowska, Agata; Genersch, Elke

    2014-07-01

    Paenibacillus larvae, the etiological agent of the globally occurring epizootic American Foulbrood (AFB) of honey bees, causes intestinal infections in honey bee larvae which develop into systemic infections inevitably leading to larval death. Massive brood mortality might eventually lead to collapse of the entire colony. Molecular mechanisms of host-microbe interactions in this system and of differences in virulence between P. larvae genotypes are poorly understood. Recently, it was demonstrated that the degradation of the peritrophic matrix lining the midgut epithelium is a key step in pathogenesis of P. larvae infections. Here, we present the isolation and identification of PlCBP49, a modular, chitin-degrading protein of P. larvae and demonstrate that this enzyme is crucial for the degradation of the larval peritrophic matrix during infection. PlCBP49 contains a module belonging to the auxiliary activity 10 (AA10, formerly CBM33) family of lytic polysaccharide monooxygenases (LPMOs) which are able to degrade recalcitrant polysaccharides. Using chitin-affinity purified PlCBP49, we provide evidence that PlCBP49 degrades chitin via a metal ion-dependent, oxidative mechanism, as already described for members of the AA10 family. Using P. larvae mutants lacking PlCBP49 expression, we analyzed in vivo biological functions of PlCBP49. In the absence of PlCBP49 expression, peritrophic matrix degradation was markedly reduced and P. larvae virulence was nearly abolished. This indicated that PlCBP49 is a key virulence factor for the species P. larvae. The identification of the functional role of PlCBP49 in AFB pathogenesis broadens our understanding of this important family of chitin-binding and -degrading proteins, especially in those bacteria that can also act as entomopathogens. PMID:25080221

  15. The T-box transcription factor 3 is a promising biomarker and a key regulator of the oncogenic phenotype of a diverse range of sarcoma subtypes.

    PubMed

    Willmer, T; Cooper, A; Sims, D; Govender, D; Prince, S

    2016-01-01

    Sarcomas represent a complex group of malignant neoplasms of mesenchymal origin and their heterogeneity poses a serious diagnostic and therapeutic challenge. There is therefore a need to elucidate the molecular mechanisms underpinning the pathogenesis of the more than 70 distinguishable sarcoma subtypes. The transcription factor TBX3, a critical developmental regulator, is overexpressed in several cancers of epithelial origin where it contributes to tumorigenesis by different molecular mechanisms. However, the status and role of TBX3 in sarcomas have not been reported. Here we show that a diverse subset of soft tissue and bone sarcoma cell lines and patient-derived sarcoma tissues express high levels of TBX3. We further explore the significance of this overexpression using a small interferring RNA approach and demonstrate that TBX3 promotes the migratory ability of chondrosarcoma, rhabdomyosarcoma and liposarcoma cells but inhibits fibrosarcoma cell migration. This suggested that TBX3 may play a key role in the development of different sarcoma subtypes by functioning as either an oncoprotein or as a brake to prevent tumour progression. To further explore this, TBX3 knockdown and overexpression cell culture models were established using chondrosarcoma and fibrosarcoma cells as representatives of each scenario, and the resulting cells were characterized with regard to key features of tumorigenesis. Results from in vitro and in vivo assays reveal that, while TBX3 promotes substrate-dependent and -independent cell proliferation, migration and tumour formation in chondrosarcoma cells, it discourages fibrosarcoma formation. Our findings provide novel evidence linking TBX3 to cancers of mesenchymal origin. Furthermore, we show that TBX3 may be a biomarker for the diagnosis of histologically dynamic sarcoma subtypes and that it impacts directly on their oncogenic phenotype. Indeed, we reveal that TBX3 may exhibit oncogene or tumour suppressor activity in sarcomas, which

  16. Factors Controlling the Position of the Martian Magnetic Pileup Boundary

    NASA Technical Reports Server (NTRS)

    Crider, D. H.; Acuna, M.; Vignes, D.; Krymskii, A.; Breus, T.; Ness, N.

    2003-01-01

    The magnetic pileup boundary (MPB) at Mars is the position where the dominant ion of the plasma changes from solar wind protons to heavy ions of planetary origin. As such, it is the obstacle to solar wind ions. We investigate the factors that influence the shape and position of the magnetic pileup boundary at Mars in order to better understand the Martian obstacle to the solar wind. Employing MGS data, we determine how the Martian MPB moves in response to factors including solar wind pressure and crustal magnetic fields. We also study the factors affecting the thickness of the MPB. Further, we compare the magnetic pileup boundary to the magnetic barrier at Venus. Direct comparison aids in our interpretation of the physics involved in the solar wind interaction with planets lacking a significant intrinsic magnetic field.

  17. Review: An urgent need for research on factors impacting adherence to and retention in care among HIV-positive youth and adolescents from key populations

    PubMed Central

    Lall, Priya; Lim, Sin How; Khairuddin, Norliana; Kamarulzaman, Adeeba

    2015-01-01

    Introduction The 50% increase in HIV-related deaths in youth and adolescents (aged 10–24) from 2005 to 2012 highlights the need to improve HIV treatment and care in this population, including treatment adherence and retention. Youth and adolescents from key populations or young key populations (YKP) in particular are highly stigmatized and may face additional barrier(s) in adhering to HIV treatment and services. We reviewed the current knowledge on treatment adherence and retention in HIV care among YKP to identify gaps in the literature and suggest future directions to improve HIV care for YKP. Methods We conducted a comprehensive literature search for YKP and their adherence to antiretroviral therapy (ART) and retention in HIV care on PsycInfo (Ovid), PubMed and Google Scholar using combinations of the keywords HIV/AIDS, ART, adolescents, young adults, adherence (or compliance), retention, men who have sex with men, transgender, injection drug users, people who inject drugs and prisoners. We included empirical studies on key populations defined by WHO; included the terms youth and adolescents and/or aged between 10 and 24; examined adherence to or retention in HIV care; and published in English-language journals. All articles were coded using NVivo. Results and discussion The systematic search yielded 10 articles on YKP and 16 articles on behaviourally infected youth and adolescents from 1999 to 2014. We found no studies reporting on youth and adolescents identified as sex workers, transgender people and prisoners. From existing literature, adherence to ART was reported to be influenced by age, access to healthcare, the burden of multiple vulnerabilities, policy involving risk behaviours and mental health. A combination of two or more of these factors negatively impacted adherence to ART among YKP. Collectively, these studies demonstrated that future programmes need to be tailored specifically to YKP to ensure adherence. Conclusions There is an urgent need for

  18. "That Was Me!": Applications of the Soundbeam MIDI Controller as a Key to Creative Communication, Learning, Independence and Joy.

    ERIC Educational Resources Information Center

    Swingler, Tim

    This paper describes the "Soundbeam MIDI (Musical Instrument Digital Interface) Controller," which allows even those students who have severe physical disabilities to create interesting aural and musical effects. Soundbeam works by emitting an invisible beam of high frequency sound inaudible to human ears. Even very slight interruptions of and…

  19. Characterization of the alpha-1,2-N-acetylglucosaminyltransferase of Neisseria gonorrhoeae, a key control point in lipooligosaccharide biosynthesis.

    PubMed

    Wakarchuk, Warren; Schur, Melissa J; St Michael, Frank; Li, Jinjuan; Eichler, Eva; Whitfield, Dennis

    2004-06-01

    The biosynthesis of the lipooligosaccharide (LOS) in Neisseria meningitidis has a control point that regulates the extension of the alpha-chain on heptose (I) of the LOS. The gene that encodes the protein responsible for this control had been identified elsewhere, but the enzyme encoded by the gene was not characterized. We have now shown that this same control mechanism operates in the related species, Neisseria gonorrhoeae, using a gene knockout and subsequent characterization of the LOS species produced. We also cloned and expressed the enzyme from both of these pathogens. Using a synthetic acceptor substrate, we have shown unequivocally that the enzyme is an alpha-1,2-N-acetylglucosaminyltransferase. Experiments with both the core oligosaccharide and the synthetic acceptors suggests that the addition of the alpha-1,2-N-acetylglucosamine moiety on the heptose (II) residue precedes the addition of the ethanolamine phosphate at the O3 position on this heptose (II), and that in the absence of the alpha-1,2-N-acetylglucosamine moiety leads to the addition of an extra ethanolamine phosphate on the heptose (II) residue. Our data do not support the hypothesis that ethanolamine phosphate at O3 of heptose (II) is added and is then required for the addition of the N-acetylglucosamine at O2 by the LgtK enzyme. This enzyme represents a control point in the biosynthesis of the LOS of this pathogen and is a potential target for therapeutic intervention. PMID:15044393

  20. Personality Factors Predicting Smartphone Addiction Predisposition: Behavioral Inhibition and Activation Systems, Impulsivity, and Self-Control

    PubMed Central

    Cho, Hyun; Jung, Dong-Jin; Kwak, Minjung; Rho, Mi Jung; Yu, Hwanjo; Kim, Dai-Jin; Choi, In Young

    2016-01-01

    The purpose of this study was to identify personality factor-associated predictors of smartphone addiction predisposition (SAP). Participants were 2,573 men and 2,281 women (n = 4,854) aged 20–49 years (Mean ± SD: 33.47 ± 7.52); participants completed the following questionnaires: the Korean Smartphone Addiction Proneness Scale (K-SAPS) for adults, the Behavioral Inhibition System/Behavioral Activation System questionnaire (BIS/BAS), the Dickman Dysfunctional Impulsivity Instrument (DDII), and the Brief Self-Control Scale (BSCS). In addition, participants reported their demographic information and smartphone usage pattern (weekday or weekend average usage hours and main use). We analyzed the data in three steps: (1) identifying predictors with logistic regression, (2) deriving causal relationships between SAP and its predictors using a Bayesian belief network (BN), and (3) computing optimal cut-off points for the identified predictors using the Youden index. Identified predictors of SAP were as follows: gender (female), weekend average usage hours, and scores on BAS-Drive, BAS-Reward Responsiveness, DDII, and BSCS. Female gender and scores on BAS-Drive and BSCS directly increased SAP. BAS-Reward Responsiveness and DDII indirectly increased SAP. We found that SAP was defined with maximal sensitivity as follows: weekend average usage hours > 4.45, BAS-Drive > 10.0, BAS-Reward Responsiveness > 13.8, DDII > 4.5, and BSCS > 37.4. This study raises the possibility that personality factors contribute to SAP. And, we calculated cut-off points for key predictors. These findings may assist clinicians screening for SAP using cut-off points, and further the understanding of SA risk factors. PMID:27533112