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Sample records for bhr group limited

  1. Utilization of Minor Actinides as a Fuel Component for Ultra-Long Life Bhr Configurations: Designs, Advantages and Limitations

    SciTech Connect

    Dr. Pavel V. Tsvetkov

    2009-05-20

    This project assessed the advantages and limitations of using minor actinides as a fuel component to achieve ultra-long life Very High Temperature Reactor (VHTR) configurations. Researchers considered and compared the capabilities of pebble-bed and prismatic core designs with advanced actinide fuels to achieve ultra-long operation without refueling. Since both core designs permit flexibility in component configuration, fuel utilization, and fuel management, it is possible to improve fissile properties of minor actinides by neutron spectrum shifting through configuration adjustments. The project studied advanced actinide fuels, which could reduce the long-term radio-toxicity and heat load of high-level waste sent to a geologic repository and enable recovery of the energy contained in spent fuel. The ultra-long core life autonomous approach may reduce the technical need for additional repositories and is capable to improve marketability of the Generation IV VHTR by allowing worldwide deployment, including remote regions and regions with limited industrial resources. Utilization of minor actinides in nuclear reactors facilitates developments of new fuel cycles towards sustainable nuclear energy scenarios.

  2. BHR equations re-derived with immiscible particle effects

    SciTech Connect

    Schwarzkopf, John Dennis; Horwitz, Jeremy A.

    2015-05-01

    Compressible and variable density turbulent flows with dispersed phase effects are found in many applications ranging from combustion to cloud formation. These types of flows are among the most challenging to simulate. While the exact equations governing a system of particles and fluid are known, computational resources limit the scale and detail that can be simulated in this type of problem. Therefore, a common method is to simulate averaged versions of the flow equations, which still capture salient physics and is relatively less computationally expensive. Besnard developed such a model for variable density miscible turbulence, where ensemble-averaging was applied to the flow equations to yield a set of filtered equations. Besnard further derived transport equations for the Reynolds stresses, the turbulent mass flux, and the density-specific volume covariance, to help close the filtered momentum and continuity equations. We re-derive the exact BHR closure equations which include integral terms owing to immiscible effects. Physical interpretations of the additional terms are proposed along with simple models. The goal of this work is to extend the BHR model to allow for the simulation of turbulent flows where an immiscible dispersed phase is non-trivially coupled with the carrier phase.

  3. Validating the BHR RANS model for variable density turbulence

    SciTech Connect

    Israel, Daniel M; Gore, Robert A; Stalsberg - Zarling, Krista L

    2009-01-01

    The BHR RANS model is a turbulence model for multi-fluid flows in which density variation plays a strong role in the turbulence processes. In this paper they demonstrate the usefulness of BHR over a wide range of flows which include the effects of shear, buoyancy, and shocks. The results are in good agreement with experimental and DNS data across the entire set of validation cases, with no need to retune model coefficients between cases. The model has potential application to a number of aerospace related flow problems.

  4. RANS modeling of RTI and HVDT with BHR3

    SciTech Connect

    Trettel, Ben

    2012-08-15

    The BHR3 turbulence model was improved to include two different scales as suggested by Livescu et al. [Liv+09, {section}4.4.6]: one for turbulent transport and the other for turbulent dissipation. Additionally, destruction terms modeled analogously to production terms were added to the turbulent mass-weighted velocity equation. New model coefficients were developed for this model. The first change was to use C{sub 2} = 1.77 for the isotropic turbulence decay coefficient rather than the k-e model's 1.92, which is outside of the experimentally measured values [ML90; KF09]. The new model coefficients were developed to accurately model a wide range of experimental and numerical results: constant and variable density Kelvin-Helmholtz instabilities, Rayleigh-Taylor instabilities, and homogeneous variable density turbulence (HVDT) [LR07]. My work focused on the buoyancy-driven flows: Rayleigh-Taylor instabilities and HVDT.

  5. Implementation and Validation of the BHR Turbulence Model in the FLAG Hydrocode

    SciTech Connect

    Denissen, Nicholas A.; Fung, Jimmy; Reisner, Jon M.; Andrews, Malcolm J.

    2012-08-29

    The BHR-2 turbulence model, developed at Los Alamos National Laboratory for variable density and compressible flows, is implemented in an Arbitrary Lagrangian-Eulerian hydrocode, FLAG. The BHR-2 formulation is discussed, with emphasis on its connection to multi-component flow formulations that underlie FLAG's treatment of multi-species flow. One-dimensional and two-dimensional validation tests are performed and compared to experiment and Eulerian simulations. Turbulence is an often studied and ubiquitous phenomenon in nature, and modeling its effects is essential in many practical applications. Specifically the behavior of turbulence in the presence of strong density gradients and compressibility is of fundamental importance in applications ranging from Inertial Confinement Fusion (ICF) [1], supernovae [2], and atmospheric flows. The BHR closure approach [3] seeks to model the physical processes at work in variable density turbulence including Kelvin-Helmholtz (KH) [4], Rayleigh-Taylor (RT) [5], and Richtmyer-Meshkov (RM) [6], driven turbulence. The effectiveness of the BHR-2 implementation has been demonstrated for variable density mixing in the KH, RT, and RM cases in an Eulerian framework [7]. The primary motivation of the present work is to implement the BHR-2 turbulence model in the Arbitrary Lagrangian-Eulerian (ALE) hydrodynamics code FLAG. The goal is not only to demonstrate results in agreement with previous Eulerian calculations, but also document behavior that arises from the underlying differences in code philosophy.

  6. Impacts of pure shocks in the BHR71 bipolar outflow

    NASA Astrophysics Data System (ADS)

    Gusdorf, A.; Riquelme, D.; Anderl, S.; Eislöffel, J.; Codella, C.; Gómez-Ruiz, A. I.; Graf, U. U.; Kristensen, L. E.; Leurini, S.; Parise, B.; Requena-Torres, M. A.; Ricken, O.; Güsten, R.

    2015-03-01

    Context. During the formation of a star, material is ejected along powerful jets that impact the ambient material. This outflow regulates star formation by e.g. inducing turbulence and heating the surrounding gas. Understanding the associated shocks is therefore essential to the study of star formation. Aims: We present comparisons of shock models with CO, H2, and SiO observations in a "pure" shock position in the BHR71 bipolar outflow. These comparisons provide an insight into the shock and pre-shock characteristics, and allow us to understand the energetic and chemical feedback of star formation on Galactic scales. Methods: New CO (Jup = 16, 11, 7, 6, 4, 3) observations from the shocked regions with the SOFIA and APEX telescopes are presented and combined with earlier H2 and SiO data (from the Spitzer and APEX telescopes). The integrated intensities are compared to a grid of models that were obtained from a magneto-hydrodynamical shock code, which calculates the dynamical and chemical structure of these regions combined with a radiative transfer module based on the "large velocity gradient" approximation. Results: The CO emission leads us to update the conclusions of our previous shock analysis: pre-shock densities of 104 cm-3 and shock velocities around 20-25 km s-1 are still constrained, but older ages are inferred (~4000 years). Conclusions: We evaluate the contribution of shocks to the excitation of CO around forming stars. The SiO observations are compatible with a scenario where less than 4% of the pre-shock SiO belongs to the grain mantles. We infer outflow parameters: a mass of 1.8 × 10-2 M⊙ was measured in our beam, in which a momentum of 0.4 M⊙ km s-1 is dissipated, corresponding to an energy of 4.2 × 1043 erg. We analyse the energetics of the outflow species by species. Comparing our results with previous studies highlights their dependence on the method: H2 observations only are not sufficient to evaluate the mass of outflows.

  7. A BHR Composite Network-Based Visualization Method for Deformation Risk Level of Underground Space

    PubMed Central

    Zheng, Wei; Zhang, Xiaoya; Lu, Qi

    2015-01-01

    This study proposes a visualization processing method for the deformation risk level of underground space. The proposed method is based on a BP-Hopfield-RGB (BHR) composite network. Complex environmental factors are integrated in the BP neural network. Dynamic monitoring data are then automatically classified in the Hopfield network. The deformation risk level is combined with the RGB color space model and is displayed visually in real time, after which experiments are conducted with the use of an ultrasonic omnidirectional sensor device for structural deformation monitoring. The proposed method is also compared with some typical methods using a benchmark dataset. Results show that the BHR composite network visualizes the deformation monitoring process in real time and can dynamically indicate dangerous zones. PMID:26011618

  8. The Chemistry and Dynamics of the Molecular Outflow in BHR71

    NASA Astrophysics Data System (ADS)

    Bovill, M. S.; Bourke, T. L.; Bergin, E. A.

    2002-12-01

    We present observations of BHR71, in rotational transitions of 12CO, 13CO and C18O and selected additional molecules. BHR71 is an isolated Bok Globule 200 pc from the Sun with an embedded protostellar system, that also contains a highly collimated outflow with unusually active chemistry. Our observations are used to probe the physical and chemical structure of this outflow. We derive the excitation temperature and opacity for several positions in the outflow using the multi-transitional CO data. With this information we estimate the mass to be 1.7 Msun and the excitation temperature to be 15 K in the outflow, slightly elevated above the temperature in the ambient gas (10 K). There is evidence for even higher temperatures towards a position in the blue lobe that is coincident with knots of H2 emission. CO column densities calculated with these temperatures are used to analyze the chemical abundances in the outflow relative to the ambient gas. SiO, CS, HCN, and H2CO all show increased abundances relative to the ambient and molecular ions (HCO+, DCO+, and N+H+) show depletion. These abundances agree qualitatively with those estimated for L1157, the only other outflow that has been extensively studied with regards to the chemistry. However, we find significant disagreements in the magnitude of the abundance changes. BHR71 abundances show agreement with chemical theory. This work was supported in part by NSF grant AST-9731923 to the SAO Summer Intern program.

  9. Researching Women's Groups Findings, Limitations, and Recommendations

    ERIC Educational Resources Information Center

    Leech, Nancy L.; Kees, Nathalie L.

    2005-01-01

    There is not a "typical" women's group, nor are there "typical" women's issues. Every women's group is diverse, with as many viewpoints and perspectives as there are members in the group. Using the group format for women is common practice with many counselors. It is interesting that there has been little empirical research reported on women's…

  10. Company profile: QuantuMDx group limited.

    PubMed

    Burn, Jamie

    2013-07-01

    QuantuMDx Group Ltd (QMDx) is a group of companies based in the International Centre for Life, Newcastle upon Tyne, UK. The Group owns the founding patent and the exclusive worldwide license for, among others, the use of nanowires and nanotubes in DNA detection. It has further developed a patent estate around the functionalization of nanowires for DNA detection, and is working with commercial partners globally to produce the Q-POC™, a handheld point-of-care genetic testing device. This novel lab-on-a-chip technology integrates and automates the sample-to-result genetic testing process in a single microfluidic channel, incorporating novel lysis technologies, the filtration of cellular constituents to achieve DNA extraction and fractionation, a rapid, thermal PCR system, and nanowires functionalized with nucleic acid probes to capture targeted sequences of genetic material. The device further makes use of novel chemistries to boost the charge of nucleotides binding to the isolated material, increasing the sensitivity and read length of the device and making it capable of robust SNP and pathogen detection. Complete with a sophisticated software package, the Q-POC™ can detect binding events through changes in resistance and effectively convert genetic code into binary code, providing a simple display of the results, complete with treatment options. The competitive advantages of this system are the sensitivity and specificity of the nanowire detection system, the extremely low cost profile of the technology, and the speed of the process, which will allow the sample-to-result detection of targeted genetic material in less than 15 min. PMID:23837475

  11. Gaia16bhu, Gaia16bhk, Gaia16bho and Gaia16bhr transients confirmed by Mercator/Maia imaging

    NASA Astrophysics Data System (ADS)

    Blanco-Cuaresma, S.; Roelens, M.; Semaan, T.; Palaversa, L.; Mowlavi, N.; Eyer, L.

    2016-09-01

    We report confirmation of Gaia Science Alerts transients Gaia16bhu, Gaia16bhk, Gaia16bho and Gaia16bhr. Images were obtained in G and R bands of the Maia instrument mounted to the Flemish 1.2m Mercator telescope at Roque de los Muchachos observatory, La Palma, Canary Islands, Spain, on 2016 September 18-19.

  12. A Poststructuralist View on Student's Project Groups: Possibilities and Limitations

    ERIC Educational Resources Information Center

    Christensen, Gerd

    2016-01-01

    The aim of this paper is to demonstrate how poststructuralism and social constructionism can contribute to the empirical research on groups in problem-based learning (PBL). The paper outlines the analytical complexity and shows, through empirical examples, the potentials and limitations of this perspective as an alternative to traditional group…

  13. More on the renormalization group limit cycle in QCD

    SciTech Connect

    Evgeny Epelbaum; Hans-Werner Hammer; Ulf-G. Meissner; Andreas Nogga

    2006-02-26

    We present a detailed study of the recently conjectured infrared renormalization group limit cycle in QCD using chiral effective field theory. We show that small increases in the up and down quark masses, corresponding to a pion mass around 200 MeV, can move QCD to the critical renormalization group trajectory for an infrared limit cycle in the three-nucleon system. At the critical values of the quark masses, the binding energies of the deuteron and its spin-singlet partner are tuned to zero and the triton has infinitely many excited states with an accumulation point at the three-nucleon threshold. At next-to-leading order in the chiral counting, we find three parameter sets where this effect occurs. For one of them, we study the structure of the three-nucleon system using both chiral and contact effective field theories in detail. Furthermore, we calculate the influence of the limit cycle on scattering observables.

  14. Resource limitation drives spatial organization in microbial groups.

    PubMed

    Mitri, Sara; Clarke, Ellen; Foster, Kevin R

    2016-06-01

    Dense microbial groups such as bacterial biofilms commonly contain a diversity of cell types that define their functioning. However, we have a limited understanding of what maintains, or purges, this diversity. Theory suggests that resource levels are key to understanding diversity and the spatial arrangement of genotypes in microbial groups, but we need empirical tests. Here we use theory and experiments to study the effects of nutrient level on spatio-genetic structuring and diversity in bacterial colonies. Well-fed colonies maintain larger well-mixed areas, but they also expand more rapidly compared with poorly-fed ones. Given enough space to expand, therefore, well-fed colonies lose diversity and separate in space over a similar timescale to poorly fed ones. In sum, as long as there is some degree of nutrient limitation, we observe the emergence of structured communities. We conclude that resource-driven structuring is central to understanding both pattern and process in diverse microbial communities. PMID:26613343

  15. Resource limitation drives spatial organization in microbial groups

    PubMed Central

    Mitri, Sara; Clarke, Ellen; Foster, Kevin R

    2016-01-01

    Dense microbial groups such as bacterial biofilms commonly contain a diversity of cell types that define their functioning. However, we have a limited understanding of what maintains, or purges, this diversity. Theory suggests that resource levels are key to understanding diversity and the spatial arrangement of genotypes in microbial groups, but we need empirical tests. Here we use theory and experiments to study the effects of nutrient level on spatio-genetic structuring and diversity in bacterial colonies. Well-fed colonies maintain larger well-mixed areas, but they also expand more rapidly compared with poorly-fed ones. Given enough space to expand, therefore, well-fed colonies lose diversity and separate in space over a similar timescale to poorly fed ones. In sum, as long as there is some degree of nutrient limitation, we observe the emergence of structured communities. We conclude that resource-driven structuring is central to understanding both pattern and process in diverse microbial communities. PMID:26613343

  16. Time-Limited Group Counseling for Chronic Home Hemodialysis Patients

    ERIC Educational Resources Information Center

    Wilson, Charles J.; And Others

    1974-01-01

    Compared effects of six sessions of group counseling of nine chronic home hemodialysis patients with a comparable no treatment control group. Comparisons revealed no significant differences between groups. Subsequent testing a year later suggested that hemodialysis patients use the defensive mechanism of denial in adapting to their condition.…

  17. Streptococcus salivarius K12 Limits Group B Streptococcus Vaginal Colonization.

    PubMed

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

    2015-09-01

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

  18. Streptococcus salivarius K12 Limits Group B Streptococcus Vaginal Colonization

    PubMed Central

    Patras, Kathryn A.; Wescombe, Philip A.; Rösler, Berenice; Hale, John D.; Tagg, John R.

    2015-01-01

    Streptococcus agalactiae (group B streptococcus [GBS]) colonizes the rectovaginal tract in 20% to 30% of women and during pregnancy can be transmitted to the newborn, causing severe invasive disease. Current routine screening and antibiotic prophylaxis have fallen short of complete prevention of GBS transmission, and GBS remains a leading cause of neonatal infection. We have investigated the ability of Streptococcus salivarius, a predominant member of the native human oral microbiota, to control GBS colonization. Comparison of the antibacterial activities of multiple S. salivarius strains by use of a deferred-antagonism test showed that S. salivarius strain K12 exhibited the broadest spectrum of activity against GBS. K12 effectively inhibited all GBS strains tested, including disease-implicated isolates from newborns and colonizing isolates from the vaginal tract of pregnant women. Inhibition was dependent on the presence of megaplasmid pSsal-K12, which encodes the bacteriocins salivaricin A and salivaricin B; however, in coculture experiments, GBS growth was impeded by K12 independently of the megaplasmid. We also demonstrated that K12 adheres to and invades human vaginal epithelial cells at levels comparable to GBS. Inhibitory activity of K12 was examined in vivo using a mouse model of GBS vaginal colonization. Mice colonized with GBS were treated vaginally with K12. K12 administration significantly reduced GBS vaginal colonization in comparison to nontreated controls, and this effect was partially dependent on the K12 megaplasmid. Our results suggest that K12 may have potential as a preventative therapy to control GBS vaginal colonization and thereby prevent its transmission to the neonate during pregnancy. PMID:26077762

  19. Streptococcus salivarius K12 Limits Group B Streptococcus Vaginal Colonization.

    PubMed

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

    2015-09-01

    Streptococcus agalactiae (group B streptococcus [GBS]) colonizes the rectovaginal tract in 20% to 30% of women and during pregnancy can be transmitted to the newborn, causing severe invasive disease. Current routine screening and antibiotic prophylaxis have fallen short of complete prevention of GBS transmission, and GBS remains a leading cause of neonatal infection. We have investigated the ability of Streptococcus salivarius, a predominant member of the native human oral microbiota, to control GBS colonization. Comparison of the antibacterial activities of multiple S. salivarius strains by use of a deferred-antagonism test showed that S. salivarius strain K12 exhibited the broadest spectrum of activity against GBS. K12 effectively inhibited all GBS strains tested, including disease-implicated isolates from newborns and colonizing isolates from the vaginal tract of pregnant women. Inhibition was dependent on the presence of megaplasmid pSsal-K12, which encodes the bacteriocins salivaricin A and salivaricin B; however, in coculture experiments, GBS growth was impeded by K12 independently of the megaplasmid. We also demonstrated that K12 adheres to and invades human vaginal epithelial cells at levels comparable to GBS. Inhibitory activity of K12 was examined in vivo using a mouse model of GBS vaginal colonization. Mice colonized with GBS were treated vaginally with K12. K12 administration significantly reduced GBS vaginal colonization in comparison to nontreated controls, and this effect was partially dependent on the K12 megaplasmid. Our results suggest that K12 may have potential as a preventative therapy to control GBS vaginal colonization and thereby prevent its transmission to the neonate during pregnancy. PMID:26077762

  20. Grouping Promotes Equality: The Effect of Recipient Grouping on Allocation of Limited Medical Resources.

    PubMed

    Colby, Helen; DeWitt, Jeff; Chapman, Gretchen B

    2015-07-01

    Decisions about allocation of scarce resources, such as transplant organs, often entail a trade-off between efficiency (i.e., maximizing the total benefit) and fairness (i.e., dividing resources equally). In three studies, we used a hypothetical scenario for transplant-organ allocation to examine allocation to groups versus individuals. Study 1 demonstrated that allocation to individuals is more efficient than allocation to groups. Study 2 identified a factor that triggers the use of fairness over efficiency: presenting the beneficiaries as one arbitrary group rather than two. Specifically, when beneficiaries were presented as one group, policymakers tended to allocate resources efficiently, maximizing total benefit. However, when beneficiaries were divided into two arbitrary groups (by hospital name), policymakers divided resources more equally across the groups, sacrificing efficiency. Study 3 replicated this effect using a redundant attribute (prognosis) to create groups and found evidence for a mediator of the grouping effect--the use of individualizing information to rationalize a more equitable allocation decision.

  1. The Effects of Test Time Limits on Performance of Culturally Defined Groups.

    ERIC Educational Resources Information Center

    Reilly, Richard R.; Evans, Franklin R.

    One of the many criticisms leveled at standardized testing is that the time limits commonly used require a speed component of performance which may act to the disadvantaged of certain culturally defined groups. Recent studies by the authors examined the question of differential time limits and group performance for standardized academic aptitude…

  2. 26 CFR 1.963-4 - Limitations on minimum distribution from a chain or group.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... chain or group. 1.963-4 Section 1.963-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... Limitations on minimum distribution from a chain or group. (a) Minimum overall tax burden—(1) In general... chain or group to the United States shareholder in an amount sufficient to constitute a...

  3. 40 CFR 97.724 - Compliance with TR SO2 Group 2 emissions limitation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Compliance with TR SO2 Group 2... (CONTINUED) AIR PROGRAMS (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS TR SO2 Group 2 Trading Program § 97.724 Compliance with TR SO2 Group 2 emissions limitation....

  4. 40 CFR 97.624 - Compliance with TR SO2 Group 1 emissions limitation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Compliance with TR SO2 Group 1... (CONTINUED) AIR PROGRAMS (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS TR SO2 Group 1 Trading Program § 97.624 Compliance with TR SO2 Group 1 emissions limitation....

  5. 40 CFR 97.724 - Compliance with TR SO2 Group 2 emissions limitation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Compliance with TR SO2 Group 2... (CONTINUED) AIR PROGRAMS (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS TR SO2 Group 2 Trading Program § 97.724 Compliance with TR SO2 Group 2 emissions limitation....

  6. 40 CFR 97.624 - Compliance with TR SO2 Group 1 emissions limitation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Compliance with TR SO2 Group 1... (CONTINUED) AIR PROGRAMS (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS TR SO2 Group 1 Trading Program § 97.624 Compliance with TR SO2 Group 1 emissions limitation....

  7. 40 CFR 97.624 - Compliance with TR SO2 Group 1 emissions limitation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Compliance with TR SO2 Group 1... (CONTINUED) AIR PROGRAMS (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS TR SO2 Group 1 Trading Program § 97.624 Compliance with TR SO2 Group 1 emissions limitation....

  8. 40 CFR 97.724 - Compliance with TR SO2 Group 2 emissions limitation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Compliance with TR SO2 Group 2... (CONTINUED) AIR PROGRAMS (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS TR SO2 Group 2 Trading Program § 97.724 Compliance with TR SO2 Group 2 emissions limitation....

  9. Spatial contraction of the Poincare group and Maxwell's equations in the electric limit

    SciTech Connect

    Reich, H.T. Wickramasekara, S.

    2010-05-15

    The contraction of the Poincare group with respect to the space translations subgroup gives rise to a group that bears a certain duality relation to the Galilei group, that is, the contraction limit of the Poincare group with respect to the time translations subgroup. In view of this duality, we call the former the dual Galilei group. A rather remarkable feature of the dual Galilei group is that the time translations constitute a central subgroup. Therewith, in unitary irreducible representations (UIRs) of the group, the Hamiltonian appears as a Casimir operator proportional to the identity H = EI, with E (and a spin value s) uniquely characterizing the representation. Hence, a physical system characterized by a UIR of the dual Galilei group displays no non-trivial time evolution. Moreover, the combined U(1) gauge group and the dual Galilei group underlie a non-relativistic limit of Maxwell's equations known as the electric limit. The analysis presented here shows that only electrostatics is possible for the electric limit, wholly in harmony with the trivial nature of time evolution governed by the dual Galilei group.

  10. The nonrelativistic limit of (central-extended) Poincare group and some consequences for quantum actualization

    SciTech Connect

    Ardenghi, Juan S.; Castagnino, M.; Campoamor-Stursberg, R.

    2009-10-15

    The nonrelativistic limit of the centrally extended Poincare group is considered and their consequences in the modal Hamiltonian interpretation of quantum mechanics are discussed [O. Lombardi and M. Castagnino, Stud. Hist. Philos. Mod. Phys 39, 380 (2008); J. Phys, Conf. Ser. 128, 012014 (2008)]. Through the assumption that in quantum field theory the Casimir operators of the Poincare group actualize, the nonrelativistic limit of the latter group yields to the actualization of the Casimir operators of the Galilei group, which is in agreement with the actualization rule of previous versions of modal Hamiltonian interpretation [Ardenghi et al., Found. Phys. (submitted)].

  11. 26 CFR 1.963-4 - Limitations on minimum distribution from a chain or group.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... rate ($26.40/ ) 26.4% Statutory percentage under section 963(b) 69% Amount distributed as pro rata... or group. 1.963-4 Section 1.963-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE....963-4 Limitations on minimum distribution from a chain or group. (a) Minimum overall tax burden—(1)...

  12. 26 CFR 1.963-4 - Limitations on minimum distribution from a chain or group.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... rate ($26.40/ ) 26.4% Statutory percentage under section 963(b) 69% Amount distributed as pro rata... chain or group. 1.963-4 Section 1.963-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE....963-4 Limitations on minimum distribution from a chain or group. (a) Minimum overall tax burden—(1)...

  13. Burrow limitations and group living in the communally rearing rodent, Octodon degus

    PubMed Central

    Ebensperger, Luis A.; Chesh, Adrian S.; Castro, Rodrigo A.; Tolhuysen, Liliana Ortiz; Quirici, Verónica; Burger, Joseph Robert; Sobrero, Raúl; Hayes, Loren D.

    2012-01-01

    Group living is thought to evolve whenever individuals attain a net fitness advantage due to reduced predation risk or enhanced foraging efficiency, but also when individuals are forced to remain in groups, which often occurs during high-density conditions due to limitations of critical resources for independent breeding. The influence of ecological limitations on sociality has been studied little in species in which reproduction is more evenly shared among group members. Previous studies in the caviomorph rodent Octodon degus (a New World hystricognath) revealed no evidence that group living confers an advantage and suggest that burrow limitations influence formation of social groups. Our objective was to examine the relevance of ecological limitations on sociality in these rodents. Our 4-year study revealed no association between degu density and use of burrow systems. The frequency with which burrow systems were used by degus was not related to the quality of these structures; only in 1 of the 4 years did the frequency of burrow use decrease with decreasing abundance of food. Neither the number of females per group nor total group size (related measures of degu sociality) changed with yearly density of degus. Although the number of males within social groups was lower in 2008, this variation was not related clearly to varying density. The percentage of females in social groups that bred was close to 99% and did not change across years of varying density. Our results suggest that sociality in degus is not the consequence of burrow limitations during breeding. Whether habitat limitations contribute to variation in vertebrate social systems is discussed. PMID:22328789

  14. Retrohoming of a Mobile Group II Intron in Human Cells Suggests How Eukaryotes Limit Group II Intron Proliferation.

    PubMed

    Truong, David M; Hewitt, F Curtis; Hanson, Joseph H; Cui, Xiaoxia; Lambowitz, Alan M

    2015-08-01

    Mobile bacterial group II introns are evolutionary ancestors of spliceosomal introns and retroelements in eukaryotes. They consist of an autocatalytic intron RNA (a "ribozyme") and an intron-encoded reverse transcriptase, which function together to promote intron integration into new DNA sites by a mechanism termed "retrohoming". Although mobile group II introns splice and retrohome efficiently in bacteria, all examined thus far function inefficiently in eukaryotes, where their ribozyme activity is limited by low Mg2+ concentrations, and intron-containing transcripts are subject to nonsense-mediated decay (NMD) and translational repression. Here, by using RNA polymerase II to express a humanized group II intron reverse transcriptase and T7 RNA polymerase to express intron transcripts resistant to NMD, we find that simply supplementing culture medium with Mg2+ induces the Lactococcus lactis Ll.LtrB intron to retrohome into plasmid and chromosomal sites, the latter at frequencies up to ~0.1%, in viable HEK-293 cells. Surprisingly, under these conditions, the Ll.LtrB intron reverse transcriptase is required for retrohoming but not for RNA splicing as in bacteria. By using a genetic assay for in vivo selections combined with deep sequencing, we identified intron RNA mutations that enhance retrohoming in human cells, but <4-fold and not without added Mg2+. Further, the selected mutations lie outside the ribozyme catalytic core, which appears not readily modified to function efficiently at low Mg2+ concentrations. Our results reveal differences between group II intron retrohoming in human cells and bacteria and suggest constraints on critical nucleotide residues of the ribozyme core that limit how much group II intron retrohoming in eukaryotes can be enhanced. These findings have implications for group II intron use for gene targeting in eukaryotes and suggest how differences in intracellular Mg2+ concentrations between bacteria and eukarya may have impacted the

  15. Retrohoming of a Mobile Group II Intron in Human Cells Suggests How Eukaryotes Limit Group II Intron Proliferation

    PubMed Central

    Truong, David M.; Hewitt, F. Curtis; Hanson, Joseph H.; Cui, Xiaoxia; Lambowitz, Alan M.

    2015-01-01

    Mobile bacterial group II introns are evolutionary ancestors of spliceosomal introns and retroelements in eukaryotes. They consist of an autocatalytic intron RNA (a “ribozyme”) and an intron-encoded reverse transcriptase, which function together to promote intron integration into new DNA sites by a mechanism termed “retrohoming”. Although mobile group II introns splice and retrohome efficiently in bacteria, all examined thus far function inefficiently in eukaryotes, where their ribozyme activity is limited by low Mg2+ concentrations, and intron-containing transcripts are subject to nonsense-mediated decay (NMD) and translational repression. Here, by using RNA polymerase II to express a humanized group II intron reverse transcriptase and T7 RNA polymerase to express intron transcripts resistant to NMD, we find that simply supplementing culture medium with Mg2+ induces the Lactococcus lactis Ll.LtrB intron to retrohome into plasmid and chromosomal sites, the latter at frequencies up to ~0.1%, in viable HEK-293 cells. Surprisingly, under these conditions, the Ll.LtrB intron reverse transcriptase is required for retrohoming but not for RNA splicing as in bacteria. By using a genetic assay for in vivo selections combined with deep sequencing, we identified intron RNA mutations that enhance retrohoming in human cells, but <4-fold and not without added Mg2+. Further, the selected mutations lie outside the ribozyme catalytic core, which appears not readily modified to function efficiently at low Mg2+ concentrations. Our results reveal differences between group II intron retrohoming in human cells and bacteria and suggest constraints on critical nucleotide residues of the ribozyme core that limit how much group II intron retrohoming in eukaryotes can be enhanced. These findings have implications for group II intron use for gene targeting in eukaryotes and suggest how differences in intracellular Mg2+ concentrations between bacteria and eukarya may have impacted the

  16. Processing power limits social group size: computational evidence for the cognitive costs of sociality.

    PubMed

    Dávid-Barrett, T; Dunbar, R I M

    2013-08-22

    Sociality is primarily a coordination problem. However, the social (or communication) complexity hypothesis suggests that the kinds of information that can be acquired and processed may limit the size and/or complexity of social groups that a species can maintain. We use an agent-based model to test the hypothesis that the complexity of information processed influences the computational demands involved. We show that successive increases in the kinds of information processed allow organisms to break through the glass ceilings that otherwise limit the size of social groups: larger groups can only be achieved at the cost of more sophisticated kinds of information processing that are disadvantageous when optimal group size is small. These results simultaneously support both the social brain and the social complexity hypotheses.

  17. Processing power limits social group size: computational evidence for the cognitive costs of sociality

    PubMed Central

    Dávid-Barrett, T.; Dunbar, R. I. M.

    2013-01-01

    Sociality is primarily a coordination problem. However, the social (or communication) complexity hypothesis suggests that the kinds of information that can be acquired and processed may limit the size and/or complexity of social groups that a species can maintain. We use an agent-based model to test the hypothesis that the complexity of information processed influences the computational demands involved. We show that successive increases in the kinds of information processed allow organisms to break through the glass ceilings that otherwise limit the size of social groups: larger groups can only be achieved at the cost of more sophisticated kinds of information processing that are disadvantageous when optimal group size is small. These results simultaneously support both the social brain and the social complexity hypotheses. PMID:23804623

  18. 40 CFR 76.7 - Revised NOX emission limitations for Group 1, Phase II boilers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 17 2012-07-01 2012-07-01 false Revised NOX emission limitations for Group 1, Phase II boilers. 76.7 Section 76.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.7 Revised...

  19. 40 CFR 76.7 - Revised NOX emission limitations for Group 1, Phase II boilers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Revised NOX emission limitations for Group 1, Phase II boilers. 76.7 Section 76.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.7 Revised...

  20. 40 CFR 76.7 - Revised NOX emission limitations for Group 1, Phase II boilers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Revised NOX emission limitations for Group 1, Phase II boilers. 76.7 Section 76.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.7 Revised...

  1. 40 CFR 76.7 - Revised NOX emission limitations for Group 1, Phase II boilers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Revised NOX emission limitations for Group 1, Phase II boilers. 76.7 Section 76.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.7 Revised...

  2. 40 CFR 76.7 - Revised NOX emission limitations for Group 1, Phase II boilers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Revised NOX emission limitations for Group 1, Phase II boilers. 76.7 Section 76.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.7 Revised...

  3. 26 CFR 56.4911-10 - Members of a limited affiliated group of organizations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 17 2011-04-01 2011-04-01 false Members of a limited affiliated group of organizations. 56.4911-10 Section 56.4911-10 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) MISCELLANEOUS EXCISE TAXES (CONTINUED) PUBLIC CHARITY EXCISE TAXES §...

  4. Limited indirect fitness benefits of male group membership in a lekking species.

    PubMed

    Lebigre, Christophe; Alatalo, Rauno V; Soulsbury, Carl D; Höglund, Jacob; Siitari, Heli

    2014-11-01

    In group living species, individuals may gain the indirect fitness benefits characterizing kin selection when groups contain close relatives. However, tests of kin selection have primarily focused on cooperatively breeding and eusocial species, whereas its importance in other forms of group living remains to be fully understood. Lekking is a form of grouping where males display on small aggregated territories, which females then visit to mate. As females prefer larger aggregations, territorial males might gain indirect fitness benefits if their presence increases the fitness of close relatives. Previous studies have tested specific predictions of kin selection models using measures such as group-level relatedness. However, a full understanding of the contribution of kin selection in the evolution of group living requires estimating individuals' indirect fitness benefits across multiple sites and years. Using behavioural and genetic data from the black grouse (Tetrao tetrix), we show that the indirect fitness benefits of group membership were very small because newcomers joined leks containing few close relatives who had limited mating success. Males' indirect fitness benefits were higher in yearlings during increasing population density but marginally changed the variation in male mating success. Kin selection acting through increasing group size is therefore unlikely to contribute substantially to the evolution and maintenance of lekking in this black grouse population. PMID:25263625

  5. Limited indirect fitness benefits of male group membership in a lekking species.

    PubMed

    Lebigre, Christophe; Alatalo, Rauno V; Soulsbury, Carl D; Höglund, Jacob; Siitari, Heli

    2014-11-01

    In group living species, individuals may gain the indirect fitness benefits characterizing kin selection when groups contain close relatives. However, tests of kin selection have primarily focused on cooperatively breeding and eusocial species, whereas its importance in other forms of group living remains to be fully understood. Lekking is a form of grouping where males display on small aggregated territories, which females then visit to mate. As females prefer larger aggregations, territorial males might gain indirect fitness benefits if their presence increases the fitness of close relatives. Previous studies have tested specific predictions of kin selection models using measures such as group-level relatedness. However, a full understanding of the contribution of kin selection in the evolution of group living requires estimating individuals' indirect fitness benefits across multiple sites and years. Using behavioural and genetic data from the black grouse (Tetrao tetrix), we show that the indirect fitness benefits of group membership were very small because newcomers joined leks containing few close relatives who had limited mating success. Males' indirect fitness benefits were higher in yearlings during increasing population density but marginally changed the variation in male mating success. Kin selection acting through increasing group size is therefore unlikely to contribute substantially to the evolution and maintenance of lekking in this black grouse population.

  6. Interplay of the scaling limit and the renormalization group: Implications for symmetry restoration

    NASA Astrophysics Data System (ADS)

    Konik, Robert M.; Saleur, Hubert; Ludwig, Andreas W.

    2002-08-01

    Symmetry restoration is usually understood as a renormalization-group induced phenomenon. In this context, the issue of whether one-loop renormalization-group equations can be trusted in predicting symmetry restoration has recently been the subject of much debate. Here we advocate a more pragmatic point of view and expand the definition of symmetry restoration to encompass all situations where the physical properties have only a weak dependence upon an anisotropy in the bare couplings. Moreover we concentrate on universal properties, and so take a scaling limit where the physics is well described by a field theory. In this context, we find a large variety of models that exhibit, for all practical purposes, symmetry restoration: even if symmetry is not restored in a strict sense, physical properties are surprisingly insensitive to the remaining anisotropy. Although we have adopted an expanded notion of symmetry restoration, we nonetheless emphasize that the scaling limit also has implications for symmetry restoration as a renormalization-group induced phenomenon. In all the models we considered, the scaling limit turns out only to permit bare couplings which are nearly isotropic and small. Then the one-loop β function should contain all the physics and higher loop orders can be neglected. We suggest that this feature generalizes to more complex models. We exhibit a large class of theories with current-current perturbations [of which the SO(8) model of interest in two-leg Hubbard ladders and armchair carbon nanotubes is one] where the one-loop β functions indicate symmetry restoration; thus we argue that these results can be trusted within the scaling limit.

  7. Nitrogen limitation as a driver of genome size evolution in a group of karst plants.

    PubMed

    Kang, Ming; Wang, Jing; Huang, Hongwen

    2015-06-25

    Genome size is of fundamental biological importance with significance in predicting structural and functional attributes of organisms. Although abundant evidence has shown that the genome size can be largely explained by differential proliferation and removal of non-coding DNA of the genome, the evolutionary and ecological basis of genome size variation remains poorly understood. Nitrogen (N) and phosphorus (P) are essential elements of DNA and protein building blocks, yet often subject to environmental limitation in natural ecosystems. Using phylogenetic comparative methods, we test this hypothesis by determining whether leaf N and P availability affects genome sizes in 99 species of Primulina (Gesneriaceae), a group of soil specialists adapted to limestone karst environment in south China. We find that genome sizes in Primulina are strongly positively correlated with plant N content, but the correlation with plant P content is not significant when phylogeny history was taken into account. This study shows for the first time that N limitation might have been a plausible driver of genome size variation in a group of plants. We propose that competition for nitrogen nutrient between DNA synthesis and cellular functions is a possible mechanism for genome size evolution in Primulina under N-limitation.

  8. Nitrogen limitation as a driver of genome size evolution in a group of karst plants

    NASA Astrophysics Data System (ADS)

    Kang, Ming; Wang, Jing; Huang, Hongwen

    2015-06-01

    Genome size is of fundamental biological importance with significance in predicting structural and functional attributes of organisms. Although abundant evidence has shown that the genome size can be largely explained by differential proliferation and removal of non-coding DNA of the genome, the evolutionary and ecological basis of genome size variation remains poorly understood. Nitrogen (N) and phosphorus (P) are essential elements of DNA and protein building blocks, yet often subject to environmental limitation in natural ecosystems. Using phylogenetic comparative methods, we test this hypothesis by determining whether leaf N and P availability affects genome sizes in 99 species of Primulina (Gesneriaceae), a group of soil specialists adapted to limestone karst environment in south China. We find that genome sizes in Primulina are strongly positively correlated with plant N content, but the correlation with plant P content is not significant when phylogeny history was taken into account. This study shows for the first time that N limitation might have been a plausible driver of genome size variation in a group of plants. We propose that competition for nitrogen nutrient between DNA synthesis and cellular functions is a possible mechanism for genome size evolution in Primulina under N-limitation.

  9. A Response to "Time-Limited Service Alternatives: Using Therapeutic Enactment in Open Group Therapy": A Dramatic Effort to Redefine Short-Term and Time-Limited Services

    ERIC Educational Resources Information Center

    Dagley, John C.; Thomas, Chippewa M.

    2008-01-01

    Therapeutic Enactment (TE) groups, as presented in the article, "Time-Limited Service Alternatives: Using Therapeutic Enactment in Open Group Therapy," offer an exciting and promising addition to the types of groups traditionally offered in university counseling centers. The brevity of member participation, the lack of empirical evidence of…

  10. An Observational Limit on the Dwarf Galaxy Population of the Local Group

    NASA Astrophysics Data System (ADS)

    Whiting, Alan B.; Hau, George K. T.; Irwin, Mike; Verdugo, Miguel

    2007-02-01

    We present the results of an all-sky, deep optical survey for faint Local Group dwarf galaxies. Candidate objects were selected from the second Palomar Observatory Sky Survey and ESO/Science Research Council survey plates, and follow-up observations were performed to determine whether they were indeed overlooked members of the Local Group. Only two galaxies (Antlia and Cetus) were discovered this way out of 206 candidates. Based on internal and external comparisons, we estimate that our visual survey is more than 77% complete for objects larger than 1' in size and with a surface brightness greater than an extremely faint limit over the 72% of the sky not obstructed by the Milky Way. Our limit of sensitivity cannot be calculated exactly, but it is certainly fainter than 25 mag arcsec-2 in R, probably 25.5 and possibly approaching 26. We conclude that there are at most one or two Local Group dwarf galaxies fitting our observational criteria still undiscovered in the clear part of the sky, and roughly a dozen hidden behind the Milky Way. Our work places the ``missing satellite problem'' on a firm quantitative observational basis. We present detailed data on all our candidates, including surface brightness measurements.

  11. Limiter

    DOEpatents

    Cohen, S.A.; Hosea, J.C.; Timberlake, J.R.

    1984-10-19

    A limiter with a specially contoured front face is provided. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution. This limiter shape accommodates the various power scrape-off distances lambda p, which depend on the parallel velocity, V/sub parallel/, of the impacting particles.

  12. Limiter

    DOEpatents

    Cohen, Samuel A.; Hosea, Joel C.; Timberlake, John R.

    1986-01-01

    A limiter with a specially contoured front face accommodates the various power scrape-off distances .lambda..sub.p, which depend on the parallel velocity, V.sub..parallel., of the impacting particles. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution.

  13. Group 2 innate lymphoid cells promote beiging of adipose and limit obesity

    PubMed Central

    Brestoff, Jonathan R.; Kim, Brian S.; Saenz, Steven A.; Stine, Rachel R.; Monticelli, Laurel A.; Sonnenberg, Gregory F.; Thome, Joseph J.; Farber, Donna L.; Lutfy, Kabirullah; Seale, Patrick; Artis, David

    2015-01-01

    Obesity is an increasingly prevalent disease regulated by genetic and environmental factors. Emerging studies indicate that immune cells, including monocytes, granulocytes and lymphocytes, regulate metabolic homeostasis and are dysregulated in obesity1,2. Group 2 innate lymphoid cells (ILC2s) can regulate adaptive immunity3,4 and eosinophil and alternatively-activated macrophage responses5, and were recently identified in murine white adipose tissue (WAT)5 where they may act to limit the development of obesity6. However, ILC2s have not been identified in human adipose tissue, and the mechanisms by which ILC2s regulate metabolic homeostasis remain unknown. Here, we identify ILC2s in human WAT and demonstrate that decreased ILC2 responses in WAT are a conserved characteristic of obesity in humans and mice. Interleukin (IL)-33 was found to be critical for the maintenance of ILC2s in WAT and in limiting adiposity in mice by increasing caloric expenditure. This was associated with recruitment of uncoupling protein 1 (UCP1)+ beige adipocytes in WAT, a process known as beiging or browning that regulates caloric expenditure7–9. IL-33-induced beiging was dependent on ILC2s, and IL-33 treatment or transfer of IL-33-elicited ILC2s was sufficient to drive beiging independently of the adaptive immune system, eosinophils or IL-4 receptor signaling. We found that ILC2s produce methionine-enkephalin peptides that can act directly on adipocytes to upregulate Ucp1 expression in vitro and that promote beiging in vivo. Collectively, these studies indicate that in addition to responding to infection or tissue damage, ILC2s can regulate adipose function and metabolic homeostasis in part via production of enkephalin peptides that elicit beiging. PMID:25533952

  14. 76 FR 54801 - Reynolds Food Packaging LLC, a Subsidiary of Reynolds Group Holding Limited, Grove City, PA...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-02

    ... Employment and Training Administration Reynolds Food Packaging LLC, a Subsidiary of Reynolds Group Holding... Reynolds Food Packaging LLC, a subsidiary of Reynolds Group Holding Limited, Grove City, Pennsylvania... make the following certification: All workers of Reynolds Food Packaging LLC, a subsidiary of...

  15. Mountain gorilla tug-of-war: Silverbacks have limited control over reproduction in multimale groups

    PubMed Central

    Bradley, Brenda J.; Robbins, Martha M.; Williamson, Elizabeth A.; Steklis, H. Dieter; Steklis, Netzin Gerald; Eckhardt, Nadin; Boesch, Christophe; Vigilant, Linda

    2005-01-01

    To determine who fathers the offspring in wild mountain gorilla groups containing more than one adult male silverback, we genotyped nearly one-fourth (n = 92) of the mountain gorillas (Gorilla beringei beringei) living in the Virunga Volcanoes region of Africa. Paternity analysis of 48 offspring born into four groups between 1985 and 1999 revealed that, although all infants were sired by within-group males, the socially dominant silverback did not always monopolize reproduction within his group. Instead, the second-ranking male sired an average of 15% of group offspring. This result, in combination with previous findings that second-ranking males fare best by not leaving the group but by staying and waiting to assume dominance even if no reproduction is possible while waiting, is not consistent with expectations from a reproductive skew model in which the silverback concedes controllable reproduction to the second-ranking male. Instead, the data suggest a “tug-of-war” scenario in which neither the dominant nor the second-ranking male has full control over his relative reproductive share. The two top-ranked males were typically unrelated and this, in combination with the mixed paternity of group offspring, means that multimale gorilla groups do not approximate family groups. Instead, as long-term assemblages of related and unrelated individuals, gorilla groups are similar to chimpanzee groups and so offer interesting possibilities for kin-biased interactions among individuals. PMID:15964984

  16. 40 CFR 76.6 - NOX emission limitations for Group 2 boilers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.6 NOX emission limitations..., the date on which the unit is required to meet Acid Rain emission reduction requirements for SO2,...

  17. 40 CFR 76.6 - NOX emission limitations for Group 2 boilers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.6 NOX emission limitations..., the date on which the unit is required to meet Acid Rain emission reduction requirements for SO2,...

  18. 40 CFR 76.6 - NOX emission limitations for Group 2 boilers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.6 NOX emission limitations..., the date on which the unit is required to meet Acid Rain emission reduction requirements for SO2,...

  19. 40 CFR 76.6 - NOX emission limitations for Group 2 boilers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.6 NOX emission limitations..., the date on which the unit is required to meet Acid Rain emission reduction requirements for SO2,...

  20. 40 CFR 76.6 - NOX emission limitations for Group 2 boilers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.6 NOX emission limitations..., the date on which the unit is required to meet Acid Rain emission reduction requirements for SO2,...

  1. Comparative studies of color fields, visual acuity fields, and movement perception limits among varsity athletes and non-varsity groups.

    PubMed

    Mizusawa, K; Sweeting, R L; Knouse, S B

    1983-06-01

    This paper examined effects of sports practice on patterns of color fields, limits of peripheral movement perception, and visual acuity field by comparing varsity ball players and non-varsity control groups. The first study measured extent of color fields and limits of horizontal and vertical meridians for peripheral movement perception of 139 college students. The second study tested visual acuity fields of female and male basketball players and female and male controls. The first study indicated that athletes had wider limits for horizontal movement perception, while the non-athletes had better vertical movement perception limits. Basketball players demonstrated color fields and limits for peripheral movement perception superior to those of soccer players. In the second study, athletes did not have any wider visual acuity fields than non-athletes, but their movement-perception limits were significantly wider than those of non-athletes.

  2. Historical limitations of determinant based exposure groupings in the rubber manufacturing industry

    PubMed Central

    Vermeulen, R; Kromhout, H

    2005-01-01

    Aims: To study the validity of using a cross-sectional industry-wide exposure survey to develop exposure groupings for epidemiological purposes that extend beyond the time period in which the exposure data were collected. Methods: Exposure determinants were used to group workers into high, medium, and low exposure groups. The contrast of this grouping and other commonly used grouping schemes based on plant and department within this exposure survey and a previously conducted survey within the same industry (and factories) were estimated and compared. Results: Grouping of inhalable and dermal exposure based on exposure determinants resulted in the highest, but still modest, contrast (ε ∼ 0.3). Classifying subjects based on a combination of plant and department resulted in a slightly lower contrast (ε ∼ 0.2). If the determinant based grouping derived from the 1997 exposure survey was used to classify workers in the 1988 survey the average contrast decreased significantly for both exposures (ε ∼ 0.1). On the contrary, the exposure classification based on plant and department increased in contrast (from ε ∼ 0.2 to ε ∼ 0.3) and retained its relative ranking overtime. Conclusions: Although determinant based groupings seem to result in more efficient groupings within a cross-sectional survey, they have to be used with caution as they might result in significant less contrast beyond the studied population or time period. It is concluded that a classification based on plant and department might be more desirable for retrospective studies in the rubber manufacturing industry, as they seem to have more historical relevance and are most likely more accurately recorded historically than information on exposure determinants in a particular industry. PMID:16234406

  3. 40 CFR 76.5 - NOX emission limitations for Group 1 boilers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.5 NOX emission limitations..., the date on which the unit is required to meet Acid Rain emission reduction requirements for SO2, the... subject to section 404(d) of the Act, the date the unit is required to meet Acid Rain emissions...

  4. 40 CFR 76.5 - NOX emission limitations for Group 1 boilers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.5 NOX emission limitations..., the date on which the unit is required to meet Acid Rain emission reduction requirements for SO2, the... 404(d) of the Act, the date the unit is required to meet Acid Rain emissions reduction...

  5. 40 CFR 76.5 - NOX emission limitations for Group 1 boilers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.5 NOX emission limitations..., the date on which the unit is required to meet Acid Rain emission reduction requirements for SO2, the... 404(d) of the Act, the date the unit is required to meet Acid Rain emissions reduction...

  6. 40 CFR 76.5 - NOX emission limitations for Group 1 boilers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.5 NOX emission limitations..., the date on which the unit is required to meet Acid Rain emission reduction requirements for SO2, the... 404(d) of the Act, the date the unit is required to meet Acid Rain emissions reduction...

  7. 40 CFR 76.5 - NOX emission limitations for Group 1 boilers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.5 NOX emission limitations..., the date on which the unit is required to meet Acid Rain emission reduction requirements for SO2, the... 404(d) of the Act, the date the unit is required to meet Acid Rain emissions reduction...

  8. Prevalence of complex activity limitations among racial/ethnic groups and Hispanic subgroups of adults: United States, 2003-2009.

    PubMed

    Ward, Brian W; Schiller, Jeannine S

    2011-09-01

    This brief has shown that racial and ethnic differences exist in the prevalence of complex activity limitations among adults. Further, within the U.S. Hispanic adult population, a number of significant differences were found in complex activity limitations among Mexican, Puerto Rican, Cuban, Central or South American, and other Hispanic adults—differences that would likely go unnoticed if the Hispanic population were treated as a single group. These disparities in the prevalence of complex activity limitations are further influenced by sex and age.

  9. Leaf hydraulic vulnerability influences species' bioclimatic limits in a diverse group of woody angiosperms.

    PubMed

    Blackman, Chris J; Brodribb, Tim J; Jordan, Gregory J

    2012-01-01

    The ability of plants to maintain water flow through leaves under water stress-induced tension (assessed as the leaf hydraulic vulnerability; P50(leaf)) is intimately linked with survival. We examined the significance of P50(leaf) as an adaptive trait in influencing the dry-end distributional limits of cool temperate woody angiosperm species. We also examined differences in within-site variability in P50(leaf) between two high-rainfall montane rainforest sites in Tasmania and Peru, respectively. A significant relationship between P50(leaf) and the 5th percentile of mean annual rainfall across each species distribution was found in Tasmania, suggesting that P50(leaf) influences species climatic limits. Furthermore, a strong correlation between P50(leaf) and the minimum rainfall availability was found using five phylogenetically independent species pairs in wet and dry evergreen tree species, suggesting that rainfall is an important selective agent in the evolution of leaf hydraulic vulnerability. Greater within-site variability in P50(leaf) was found among dominant montane rainforest species in Tasmania than in Peru and this result is discussed within the context of differences in spatial and temporal environmental heterogeneity and parochial historical ecology.

  10. Two's company, three's a crowd: food and shelter limitation outweigh the benefits of group living in a shoaling fish.

    PubMed

    Ford, John R; Swearer, Stephen E

    2013-05-01

    Identifying how density and number-dependent processes regulate populations is important for predicting population response to environmental change. Species that live in groups, such as shoaling fish, can experience both direct density-dependent mortality through resource limitation and inverse number-dependent mortality via increased feeding rates and predator evasion in larger groups. To investigate the role of these processes in a temperate reef fish population, we manipulated the density and group size of the shoaling species Trachinops caudimaculatus on artificial patch reefs at two locations with different predator fields in Port Phillip Bay, Australia. We compared mortality over four weeks to estimates of predator abundance and per capita availability of refuge and food to identify mechanisms for density or number dependence. Mortality was strongly directly density dependent throughout the experiment, regardless of the dominant predator group; however, the limiting resource driving this effect changed over time. In the first two weeks when densities were highest, density-dependent mortality was best explained by refuge competition and the abundance of benthic predators. During the second two weeks, food competition best explained the pattern of mortality. We detected no effect of group size at either location, even where pelagic-predator abundance was high. Overall, direct density effects were much stronger than those of group size, suggesting little survival advantage to shoaling on isolated patch reefs where resource competition is high. This study is the first to observe a temporal shift in density-dependent mechanisms in reef fish, and the first to observe food limitation on short temporal scales. Food competition may therefore be an important regulator of postsettlement reef fish cohorts after the initial intense effects of refuge limitation and predation. PMID:23858647

  11. Two's company, three's a crowd: food and shelter limitation outweigh the benefits of group living in a shoaling fish.

    PubMed

    Ford, John R; Swearer, Stephen E

    2013-05-01

    Identifying how density and number-dependent processes regulate populations is important for predicting population response to environmental change. Species that live in groups, such as shoaling fish, can experience both direct density-dependent mortality through resource limitation and inverse number-dependent mortality via increased feeding rates and predator evasion in larger groups. To investigate the role of these processes in a temperate reef fish population, we manipulated the density and group size of the shoaling species Trachinops caudimaculatus on artificial patch reefs at two locations with different predator fields in Port Phillip Bay, Australia. We compared mortality over four weeks to estimates of predator abundance and per capita availability of refuge and food to identify mechanisms for density or number dependence. Mortality was strongly directly density dependent throughout the experiment, regardless of the dominant predator group; however, the limiting resource driving this effect changed over time. In the first two weeks when densities were highest, density-dependent mortality was best explained by refuge competition and the abundance of benthic predators. During the second two weeks, food competition best explained the pattern of mortality. We detected no effect of group size at either location, even where pelagic-predator abundance was high. Overall, direct density effects were much stronger than those of group size, suggesting little survival advantage to shoaling on isolated patch reefs where resource competition is high. This study is the first to observe a temporal shift in density-dependent mechanisms in reef fish, and the first to observe food limitation on short temporal scales. Food competition may therefore be an important regulator of postsettlement reef fish cohorts after the initial intense effects of refuge limitation and predation.

  12. Roles of long-range tertiary interactions in limiting dynamics of the Tetrahymena group I ribozyme.

    PubMed

    Shi, Xuesong; Bisaria, Namita; Benz-Moy, Tara L; Bonilla, Steve; Pavlichin, Dmitri S; Herschlag, Daniel

    2014-05-01

    We determined the effects of mutating the long-range tertiary contacts of the Tetrahymena group I ribozyme on the dynamics of its substrate helix (referred to as P1) and on catalytic activity. Dynamics were assayed by fluorescence anisotropy of the fluorescent base analogue, 6-methyl isoxanthopterin, incorporated into the P1 helix, and fluorescence anisotropy and catalytic activity were measured for wild type and mutant ribozymes over a range of conditions. Remarkably, catalytic activity correlated with P1 anisotropy over 5 orders of magnitude of activity, with a correlation coefficient of 0.94. The functional and dynamic effects from simultaneous mutation of the two long-range contacts that weaken P1 docking are cumulative and, based on this RNA's topology, suggest distinct underlying origins for the mutant effects. Tests of mechanistic predictions via single molecule FRET measurements of rate constants for P1 docking and undocking suggest that ablation of the P14 tertiary interaction frees P2 and thereby enhances the conformational space explored by the undocked attached P1 helix. In contrast, mutation of the metal core tertiary interaction disrupts the conserved core into which the P1 helix docks. Thus, despite following a single correlation, the two long-range tertiary contacts facilitate P1 helix docking by distinct mechanisms. These results also demonstrate that a fluorescence anisotropy probe incorporated into a specific helix within a larger RNA can report on changes in local helical motions as well as differences in more global dynamics. This ability will help uncover the physical properties and behaviors that underlie the function of RNAs and RNA/protein complexes.

  13. Roles of Long-Range Tertiary Interactions in Limiting Dynamics of the Tetrahymena Group I Ribozyme

    PubMed Central

    2015-01-01

    We determined the effects of mutating the long-range tertiary contacts of the Tetrahymena group I ribozyme on the dynamics of its substrate helix (referred to as P1) and on catalytic activity. Dynamics were assayed by fluorescence anisotropy of the fluorescent base analogue, 6-methyl isoxanthopterin, incorporated into the P1 helix, and fluorescence anisotropy and catalytic activity were measured for wild type and mutant ribozymes over a range of conditions. Remarkably, catalytic activity correlated with P1 anisotropy over 5 orders of magnitude of activity, with a correlation coefficient of 0.94. The functional and dynamic effects from simultaneous mutation of the two long-range contacts that weaken P1 docking are cumulative and, based on this RNA’s topology, suggest distinct underlying origins for the mutant effects. Tests of mechanistic predictions via single molecule FRET measurements of rate constants for P1 docking and undocking suggest that ablation of the P14 tertiary interaction frees P2 and thereby enhances the conformational space explored by the undocked attached P1 helix. In contrast, mutation of the metal core tertiary interaction disrupts the conserved core into which the P1 helix docks. Thus, despite following a single correlation, the two long-range tertiary contacts facilitate P1 helix docking by distinct mechanisms. These results also demonstrate that a fluorescence anisotropy probe incorporated into a specific helix within a larger RNA can report on changes in local helical motions as well as differences in more global dynamics. This ability will help uncover the physical properties and behaviors that underlie the function of RNAs and RNA/protein complexes. PMID:24738560

  14. Limited novel influenza A (H1N1) 09 infection in travelling high‐school tour group

    PubMed Central

    Mardani, Janine; Calder, Lester; Laurie, Karen; Barr, Ian; Kelso, Anne; Jones, Nicholas

    2010-01-01

    Please cite this paper as: Mardani et al. (2011) Limited novel influenza A (H1N1) 09 infection in travelling high‐school tour group. Influenza and Other Respiratory Viruses 5(1), 47–51. Background  A single case of novel influenza A (H1N1) 09 infection was identified by PCR among a New Zealand high‐school group that toured California in April 2009. Close monitoring of the tour group and their New Zealand contacts identified 11 other tour members with respiratory symptoms who were investigated. In all nine instances where nasopharyngeal swabs were indicated, tests were negative for novel influenza A (H1N1) 09 by PCR. Objective  To determine whether serology could identify any cases of novel influenza A (H1N1) 09 that had not been detected by PCR. Methods  Acute and convalescent serological testing for antibodies against pandemic (H1N1) 2009 and seasonal A (H1N1) influenza viruses using haemagglutination inhibition assays and microneutralisation assays. Results  Serological analysis of symptomatic tour members identified a further possible case of novel influenza A (H1N1) 09 infection. The possible case had not been tested by PCR because he or she had already received prophylaxis with oseltamivir. Conclusions  These findings suggest infection among tour group members was limited despite prolonged periods of close contact during travel. Furthermore, multiple public health interventions are likely to have effectively prevented an outbreak following the tour group’s return. PMID:21138540

  15. Efimov-like phase of a three-stranded DNA and the renormalization-group limit cycle

    NASA Astrophysics Data System (ADS)

    Pal, Tanmoy; Sadhukhan, Poulomi; Bhattacharjee, Somendra M.

    2015-04-01

    A three-stranded DNA with short range base pairings only is known to exhibit a classical analog of the quantum Efimov effect, viz., a three-chain bound state at the two-chain melting point where no two are bound. By using a nonperturbative renormalization-group method for a rigid duplex DNA and a flexible third strand, with base pairings and strand exchange, we show that the Efimov-DNA is associated with a limit cycle type behavior of the flow of an effective three-chain interaction. The analysis also shows that thermally generated bubbles play an essential role in producing the effect. A toy model for the flow equations shows the limit cycle in an extended three-dimensional parameter space of the two-chain coupling and a complex three-chain interaction.

  16. Efimov-like phase of a three-stranded DNA and the renormalization-group limit cycle.

    PubMed

    Pal, Tanmoy; Sadhukhan, Poulomi; Bhattacharjee, Somendra M

    2015-04-01

    A three-stranded DNA with short range base pairings only is known to exhibit a classical analog of the quantum Efimov effect, viz., a three-chain bound state at the two-chain melting point where no two are bound. By using a nonperturbative renormalization-group method for a rigid duplex DNA and a flexible third strand, with base pairings and strand exchange, we show that the Efimov-DNA is associated with a limit cycle type behavior of the flow of an effective three-chain interaction. The analysis also shows that thermally generated bubbles play an essential role in producing the effect. A toy model for the flow equations shows the limit cycle in an extended three-dimensional parameter space of the two-chain coupling and a complex three-chain interaction.

  17. Efimov-like phase of a three-stranded DNA and the renormalization-group limit cycle.

    PubMed

    Pal, Tanmoy; Sadhukhan, Poulomi; Bhattacharjee, Somendra M

    2015-04-01

    A three-stranded DNA with short range base pairings only is known to exhibit a classical analog of the quantum Efimov effect, viz., a three-chain bound state at the two-chain melting point where no two are bound. By using a nonperturbative renormalization-group method for a rigid duplex DNA and a flexible third strand, with base pairings and strand exchange, we show that the Efimov-DNA is associated with a limit cycle type behavior of the flow of an effective three-chain interaction. The analysis also shows that thermally generated bubbles play an essential role in producing the effect. A toy model for the flow equations shows the limit cycle in an extended three-dimensional parameter space of the two-chain coupling and a complex three-chain interaction. PMID:25974437

  18. Conditional solvation thermodynamics of isoleucine in model peptides and the limitations of the group-transfer model.

    PubMed

    Tomar, Dheeraj S; Weber, Valéry; Pettitt, B Montgomery; Asthagiri, D

    2014-04-17

    The hydration thermodynamics of the amino acid X relative to the reference G (glycine) or the hydration thermodynamics of a small-molecule analog of the side chain of X is often used to model the contribution of X to protein stability and solution thermodynamics. We consider the reasons for successes and limitations of this approach by calculating and comparing the conditional excess free energy, enthalpy, and entropy of hydration of the isoleucine side chain in zwitterionic isoleucine, in extended penta-peptides, and in helical deca-peptides. Butane in gauche conformation serves as a small-molecule analog for the isoleucine side chain. Parsing the hydrophobic and hydrophilic contributions to hydration for the side chain shows that both of these aspects of hydration are context-sensitive. Furthermore, analyzing the solute-solvent interaction contribution to the conditional excess enthalpy of the side chain shows that what is nominally considered a property of the side chain includes entirely nonobvious contributions of the background. The context-sensitivity of hydrophobic and hydrophilic hydration and the conflation of background contributions with energetics attributed to the side chain limit the ability of a single scaling factor, such as the fractional solvent exposure of the group in the protein, to map the component energetic contributions of the model-compound data to their value in the protein. But ignoring the origin of cancellations in the underlying components the group-transfer model may appear to provide a reasonable estimate of the free energy for a given error tolerance.

  19. Efficacy of a group-based dietary intervention for limiting gestational weight gain among obese women: a randomized trial

    PubMed Central

    Vesco, Kimberly K.; Karanja, Njeri; King, Janet C.; Gillman, Matthew W.; Leo, Michael C.; Perrin, Nancy; McEvoy, Cindy T.; Eckhardt, Cara L.; Smith, K. Sabina; Stevens, Victor J.

    2014-01-01

    Objective Observational studies suggest that minimal gestational weight gain (GWG) may optimize pregnancy outcomes for obese women. This trial tested the efficacy of a group-based weight management intervention for limiting GWG among obese women. Methods We randomized 114 obese women (BMI [mean±SD] 36.7±4.9 kg/m2) between 7–21 weeks’ (14.9±2.6) gestation to intervention (n=56) or usual care control conditions (n=58). The intervention included individualized calorie goals, advice to maintain weight within 3% of randomization and follow the Dietary Approaches to Stop Hypertension dietary pattern without sodium restriction, and attendance at weekly group meetings until delivery. Control participants received one-time dietary advice. Our three main outcomes were maternal weight change from randomization to 2 weeks postpartum and from randomization to 34 weeks gestation, and newborn large-for-gestational age (birth weight >90th percentile, LGA). Results Intervention participants gained less weight from randomization to 34 weeks gestation (5.0 vs 8.4 kg, mean difference=−3.4 kg, 95% CI [−5.1, −1.8]), and from randomization to 2 weeks postpartum (−2.6 vs +1.2 kg, mean difference=−3.8 kg, 95% CI [−5.9, −1.7]). They also had a lower proportion of LGA babies (9% vs. 26%, odds ratio=0.28, 95% CI [0.09, 0.84]). Conclusions The intervention resulted in lower GWG and lower prevalence of LGA newborns. PMID:25164259

  20. Focus Group Evaluation of “Secret Feelings”: A Depression Fotonovela for Latinos With Limited English Proficiency

    PubMed Central

    Cabassa, Leopoldo J.; Contreras, Sandra; Aragón, Rebeca; Molina, Gregory B.; Baron, Melvin

    2013-01-01

    In this study, the authors examined reactions of Latino adults with limited English proficiency (LEP) to a culturally and linguistically adapted depression fotonovela, titled “Secret Feelings.” Fotonovelas are popular health education tools that use posed photographs, text bubbles with simple text, and dramatic narratives to engage audiences and raise their awareness and knowledge about specific health issues. Four focus groups (N = 32) were conducted at an adult school program (e.g., GED classes). Content analysis was used to generate themes from transcripts and memos. “Secret Feelings” was viewed as an entertaining, engaging, and educational tool that helped combat stigma toward depression and its treatments in the Latino community. Despite learning about depression, participants reported they wanted more information about the causes of depression, the process of recovery, and felt that the story did not shift their apprehensions toward antidepressants. The findings suggest that “Secret Feelings” is a promising depression literacy tool for Latinos with LEP that can raise awareness and knowledge about depression and its treatments, reduce stigma toward depression and antidepressant medications, and model appropriate help-seeking behaviors. PMID:21807951

  1. XMM-Newton and Chandra Observations of the Galaxy Group NGC 5044. 1; Evidence for Limited Multiphase Hot Gas

    NASA Technical Reports Server (NTRS)

    Buote, David A.; Lewis, Aaron D.; Brighenti, Fabrizio; Mathews, William G.

    2003-01-01

    Using new XMM and Chandra observations, we present an analysis of the temperature structure of the hot gas within a radius of 100 kpc of the bright nearby galaxy group NGC 5044. A spectral deprojection analysis of data extracted from circular annuli reveals that a two-temperature model (2T) of the hot gas is favored over single-phase or cooling flow (M = 4.5 +/- 0.2 solar mass/yr) models within the central approx.30 kpc. Alternatively, the data can be fitted equally well if the temperature within each spherical shell varies continuously from approx.T(sub h) to T(sub c) approx. T(sub h)/2, but no lower. The high spatial resolution of the Chandra data allows us to determine that the temperature excursion T(sub h) approaches T(sub c) required in each shell exceeds the temperature range between the boundaries of the same shell in the best-fitting single-phase model. This is strong evidence for a multiphase gas having a limited temperature range. We do not find any evidence that azimuthal temperature variations within each annulus on the sky can account for the range in temperatures within each shell. We provide a detailed investigation of the systematic errors on the derived spectral models considering the effects of calibration, plasma codes, bandwidth, variable NH, and background rate. We find that the RGS gratings and the EPIC and ACIS CCDs give fully consistent results when the same models are fitted over the same energy ranges for each instrument. The cooler component of the 2T model has a temperature (T(sub c) approx. 0.7 keV) similar to the kinetic temperature of the stars. The hot phase has a temperature (T(sub h) approx. 1.4 keV) characteristic of the virial temperature of the solar mass halo expected in the NGC 5044 group. However, in view of the morphological disturbances and X-ray holes visible in the Chandra image within R approx. equals 10 kpc, bubbles of gas heated to approx.T(sub h) in this region may be formed by intermittent AGN feedback. Some

  2. Role of competition-induced anxiety in limiting the beneficial impact of positive behavior by an out-group member.

    PubMed

    Wilder, D A; Shapiro, P N

    1989-01-01

    Several variables influence whether contact with a favorable out-group member has a beneficial impact on intergroup relations. In two experiments we examined the effect of competition-induced anxiety on reaction to the behavior of a favorable out-group member. In Experiment 1 a competitive context produced (a) anxiety, relative to a cooperative context, and (b) assimilation of a favorable out-group member to the unfavorable majority. Experiment 2 replicated this finding and showed that when anxiety was reduced, those who expected to compete with the out-group formed a more favorable and veridical impression of the positive out-group member. Taken together, results support the hypothesis that the expectation of an unpleasant competitive encounter with an out-group generates anxiety that, in turn, lessens the impact of positive behavior by an out-group member. Implications of this research for intergroup relations are discussed. PMID:2926617

  3. A Pilot Study for a Structured, Time-Limited Therapy Group for Sexually Abused Pre-Adolescent Children.

    ERIC Educational Resources Information Center

    Corder, Billie F.; And Others

    1990-01-01

    Structured group therapy techniques were developed to foster mastery skill development and defense mechanisms in the treatment of eight sexually abused female children, aged six to eight. The techniques included development of intellectualization defenses through board games, cathartic exploration of feelings through art and storytelling, and…

  4. ON THE LIMIT DISTRIBUTION OF THE NUMBER OF SOLUTIONS OF THE EQUATION x^k = a IN THE SYMMETRIC GROUP S_n

    NASA Astrophysics Data System (ADS)

    Pavlov, A. I.

    1983-02-01

    The limit distribution of the number of solutions of the equation x^k = a as n \\to \\infty is investigated for a fixed integer k \\geq 2, where a is in the symmetric group S_n of degree n.Bibliography: 2 titles.

  5. Bonobos show limited social tolerance in a group setting: a comparison with chimpanzees and a test of the relational model.

    PubMed

    Cronin, Katherine A; De Groot, Evelien; Stevens, Jeroen M G

    2015-01-01

    Social tolerance is a core aspect of primate social relationships with implications for the evolution of cooperation, prosociality and social learning. We measured the social tolerance of bonobos in an experiment recently validated with chimpanzees to allow for a comparative assessment of group-level tolerance, and found that the bonobo group studied here exhibited lower social tolerance on average than chimpanzees in this paradigm. Furthermore, following the Relational Model of de Waal, we investigated whether bonobos responded to an increased potential for social conflict with tolerance, conflict avoidance or conflict escalation, and found that only behaviours indicative of conflict escalation differed across conditions. Taken together, these findings contribute to the current debate over the level of social tolerance of bonobos and lend support to the position that the social tolerance of bonobos may not be notably high compared with other primates. PMID:25926027

  6. Bonobos show limited social tolerance in a group setting: a comparison with chimpanzees and a test of the relational model.

    PubMed

    Cronin, Katherine A; De Groot, Evelien; Stevens, Jeroen M G

    2015-01-01

    Social tolerance is a core aspect of primate social relationships with implications for the evolution of cooperation, prosociality and social learning. We measured the social tolerance of bonobos in an experiment recently validated with chimpanzees to allow for a comparative assessment of group-level tolerance, and found that the bonobo group studied here exhibited lower social tolerance on average than chimpanzees in this paradigm. Furthermore, following the Relational Model of de Waal, we investigated whether bonobos responded to an increased potential for social conflict with tolerance, conflict avoidance or conflict escalation, and found that only behaviours indicative of conflict escalation differed across conditions. Taken together, these findings contribute to the current debate over the level of social tolerance of bonobos and lend support to the position that the social tolerance of bonobos may not be notably high compared with other primates.

  7. Limiting activity coefficients of aqueous flavour systems at 298 K by the group contribution solvation (GCS) model

    NASA Astrophysics Data System (ADS)

    Nanu, Diana E.; de Loos, Theodoor W.

    In this work a new approach for using the GCS model is applied to predict the infinite dilution activity coefficients, γ∞, for aroma compounds in water. It involves the use of a better expression for the combinatorial contribution to γ∞, and a different treatment of the values of the α-scaling factors used in the cavity size definition in the quantum chemical solvation calculations. The α values for each functional group in the solvation calculations in water are optimized based on few experimental data of γ∞. The present approach is applied for describing aqueous systems of n-alkanols and methyl-ketones. The results discussed here show that the predicted γ∞ values are within the experimental accuracy for most of the compounds, and are more accurate than predictions using the classical UNIFAC-type group contribution models. Furthermore, a simple group contribution approach was developed based on quantum-computed quantities, which makes it possible to extend the applicability of the model without expensive quantum calculations. It is shown that such an approach is able to describe γ∞ well, even for larger systems.

  8. Comparative Study of Bronchial Hyperresponsiveness Between Football and Judo Groups in Prepubertal Boys

    PubMed Central

    Triki, Moez; Rebai, Haithem; Aouichaoui, Chirine; Shamssain, Mohammed; Masmoudi, Kaouthar; Fellmann, Nicole; Zouari, Hela; Zouari, Nouri; Tabka, Zouhair

    2015-01-01

    Background: Exercise induced bronchospasm (EIB) commonly occurs during exercise. The comparative effects of different sports on airway responsiveness among prepubertal boys remain to be determined. Objectives: To assess differences in post exercise spirometry between footballers, judokas and a control group in prepubertal boys. Patients and Methods: A total of ninety six prepubertal boys were studied. Bronchial hyper responsiveness (BHR) to exercise challenge test was defined by a diagnosis of baseline spirometry, followed by an incremental exercise test. To date, the best test to confirm EIB may simply be standard pulmonary function testing before and after high-intensity exercise. A 10% or greater post-challenge fall in forced expiratory volume in FEV1 is used as a diagnostic criterion. Results: There was no significant difference in baseline spirometry between all groups (P > 0.05). The post exercise spirometry test revealed the presence of EIB in 16 of 32 (50%) footballers against 9 out of 32 (28.12%) in both judokas and control subjects at 5 min after the exercise. Also, there was a significantly higher decrease (P < 0.05) in mean FEV1 at 5 minuts in footballers (-9.60 ± 6.18) compared to judokas (-5.41 ± 5.85). Conclusions: The footballers have more BHR than judokas, especially at 5min after the exercise. This may be due to prolonged hyperventilation, atopy and increased exposure to inhaled allergens and pollutants during training and competition. PMID:26448837

  9. International neurocognitive normative study: neurocognitive comparison data in diverse resource-limited settings: AIDS Clinical Trials Group A5271.

    PubMed

    Robertson, K; Jiang, H; Evans, S R; Marra, C M; Berzins, B; Hakim, J; Sacktor, N; Silva, M Tulius; Campbell, T B; Nair, A; Schouten, J; Kumwenda, J; Supparatpinyo, K; Tripathy, S; Kumarasamy, N; la Rosa, A; Montano, S; Mwafongo, A; Firnhaber, C; Sanne, I; Naini, L; Amod, F; Walawander, A

    2016-08-01

    Infrastructure for conducting neurological research in resource-limited settings (RLS) is limited. The lack of neurological and neuropsychological (NP) assessment and normative data needed for clinical interpretation impedes research and clinical care. Here, we report on ACTG 5271, which provided neurological training of clinical site personnel and collected neurocognitive normative comparison data in diverse settings. At ten sites in seven RLS countries, we provided training for NP assessments. We collected normative comparison data on HIV- participants from Brazil (n = 240), India (n = 480), Malawi (n = 481), Peru (n = 239), South Africa (480), Thailand (n = 240), and Zimbabwe (n = 240). Participants had a negative HIV test within 30 days before standardized NP exams were administered at baseline and 770 at 6 months. Participants were enrolled in eight strata, gender (female and male), education (<10 and ≥10 years), and age (<35 and ≥35 years). Of 2400 enrolled, 770 completed the 6-month follow-up. As expected, significant between-country differences were evident in all the neurocognitive test scores (p < 0.0001). There was variation between the age, gender, and education strata on the neurocognitive tests. Age and education were important variables for all tests; older participants had poorer performance, and those with higher education had better performance. Women had better performance on verbal learning/memory and speed of processing tests, while men performed better on motor tests. This study provides the necessary neurocognitive normative data needed to build infrastructure for future neurological and neurocognitive studies in diverse RLS. These normative data are a much-needed resource for both clinicians and researchers. PMID:26733457

  10. International neurocognitive normative study: neurocognitive comparison data in diverse resource-limited settings: AIDS Clinical Trials Group A5271.

    PubMed

    Robertson, K; Jiang, H; Evans, S R; Marra, C M; Berzins, B; Hakim, J; Sacktor, N; Silva, M Tulius; Campbell, T B; Nair, A; Schouten, J; Kumwenda, J; Supparatpinyo, K; Tripathy, S; Kumarasamy, N; la Rosa, A; Montano, S; Mwafongo, A; Firnhaber, C; Sanne, I; Naini, L; Amod, F; Walawander, A

    2016-08-01

    Infrastructure for conducting neurological research in resource-limited settings (RLS) is limited. The lack of neurological and neuropsychological (NP) assessment and normative data needed for clinical interpretation impedes research and clinical care. Here, we report on ACTG 5271, which provided neurological training of clinical site personnel and collected neurocognitive normative comparison data in diverse settings. At ten sites in seven RLS countries, we provided training for NP assessments. We collected normative comparison data on HIV- participants from Brazil (n = 240), India (n = 480), Malawi (n = 481), Peru (n = 239), South Africa (480), Thailand (n = 240), and Zimbabwe (n = 240). Participants had a negative HIV test within 30 days before standardized NP exams were administered at baseline and 770 at 6 months. Participants were enrolled in eight strata, gender (female and male), education (<10 and ≥10 years), and age (<35 and ≥35 years). Of 2400 enrolled, 770 completed the 6-month follow-up. As expected, significant between-country differences were evident in all the neurocognitive test scores (p < 0.0001). There was variation between the age, gender, and education strata on the neurocognitive tests. Age and education were important variables for all tests; older participants had poorer performance, and those with higher education had better performance. Women had better performance on verbal learning/memory and speed of processing tests, while men performed better on motor tests. This study provides the necessary neurocognitive normative data needed to build infrastructure for future neurological and neurocognitive studies in diverse RLS. These normative data are a much-needed resource for both clinicians and researchers.

  11. Cross-species amplification of microsatellites reveals incongruence in the molecular variation and taxonomic limits of the Pilosocereus aurisetus group (Cactaceae).

    PubMed

    Moraes, Evandro M; Perez, Manolo F; Téo, Mariana F; Zappi, Daniela C; Taylor, Nigel P; Machado, Marlon C

    2012-09-01

    The Pilosocereus aurisetus group contains eight cactus species restricted to xeric habitats in eastern and central Brazil that have an archipelago-like distribution. In this study, 5-11 microsatellite markers previously designed for Pilosocereus machrisii were evaluated for cross-amplification and polymorphisms in ten populations from six species of the P. aurisetus group. The genotypic information was subsequently used to investigate the genetic relationships between the individuals, populations, and species analyzed. Only the Pmac101 locus failed to amplify in all of the six analyzed species, resulting in an 88 % success rate. The number of alleles per polymorphic locus ranged from 2 to 12, and the most successfully amplified loci showed at least one population with a larger number of alleles than were reported in the source species. The population relationships revealed clear genetic clustering in a neighbor-joining tree that was partially incongruent with the taxonomic limits between the P. aurisetus and P. machrisii species, a fact which parallels the problematic taxonomy of the P. aurisetus group. A Bayesian clustering analysis of the individual genotypes confirmed the observed taxonomic incongruence. These microsatellite markers provide a valuable resource for facilitating large-scale genetic studies on population structures, systematics and evolutionary history in this group.

  12. Designs for testing group-based interventions with limited numbers of social units: The dynamic wait-listed and regression point displacement designs

    PubMed Central

    Wyman, Peter A.; Brown, C. Hendricks

    2015-01-01

    The dynamic wait-listed design (DWLD) and regression point displacement design (RPDD) address several challenges in evaluating group-based interventions when there is a limited number of groups. Both DWLD and RPDD utilize efficiencies that increase statistical power and can enhance balance between community needs and research priorities. The DWLD blocks on more time units than traditional wait-listed designs, thereby increasing the proportion of a study period during which intervention and control conditions can be compared, and can also improve logistics of implementing intervention across multiple sites and strengthen fidelity. We discuss DWLDs in the larger context of roll-out randomized designs and compare it with its cousin the Stepped Wedge design. The RPDD uses archival data on the population of settings from which intervention unit(s) are selected to create expected posttest scores for units receiving intervention, to which actual posttest scores are compared. High pretest-posttest correlations give the RPDD statistical power for assessing intervention impact even when one or a few settings receive intervention. RPDD works best when archival data are available over a number of years prior to and following intervention. If intervention units were not randomly selected, propensity scores can be used to control for nonrandom selection factors. Examples are provided of the DWLD and RPDD used to evaluate, respectively, suicide prevention training (QPR) in 32 schools and a violence prevention program (CeaseFire) in 2 Chicago police districts over a 10-year period. How DWLD and RPDD address common threats to internal and external validity, as well as their limitations, are discussed. PMID:25481512

  13. Designs for Testing Group-Based Interventions with Limited Numbers of Social Units: The Dynamic Wait-Listed and Regression Point Displacement Designs.

    PubMed

    Wyman, Peter A; Henry, David; Knoblauch, Shannon; Brown, C Hendricks

    2015-10-01

    The dynamic wait-listed design (DWLD) and regression point displacement design (RPDD) address several challenges in evaluating group-based interventions when there is a limited number of groups. Both DWLD and RPDD utilize efficiencies that increase statistical power and can enhance balance between community needs and research priorities. The DWLD blocks on more time units than traditional wait-listed designs, thereby increasing the proportion of a study period during which intervention and control conditions can be compared, and can also improve logistics of implementing intervention across multiple sites and strengthen fidelity. We discuss DWLDs in the larger context of roll-out randomized designs and compare it with its cousin the Stepped Wedge design. The RPDD uses archival data on the population of settings from which intervention unit(s) are selected to create expected posttest scores for units receiving intervention, to which actual posttest scores are compared. High pretest-posttest correlations give the RPDD statistical power for assessing intervention impact even when one or a few settings receive intervention. RPDD works best when archival data are available over a number of years prior to and following intervention. If intervention units were not randomly selected, propensity scores can be used to control for non-random selection factors. Examples are provided of the DWLD and RPDD used to evaluate, respectively, suicide prevention training (QPR) in 32 schools and a violence prevention program (CeaseFire) in two Chicago police districts over a 10-year period. How DWLD and RPDD address common threats to internal and external validity, as well as their limitations, are discussed.

  14. The self-defining critical group and its application to a measured check of the derived limit for [sup 125]I in drinking water

    SciTech Connect

    Bowlt, C.; Howe, J.R. )

    1992-12-01

    Using a series of daily measurements of [sup 125]I in the drinking water of North Surrey, England, from November 1988 through May 1990, the accumulated activities in the thyroids of adults drinking such water were calculated on the assumption that the fraction of ingested iodine taken up by the thyroid was f = 0.3 and the tap water consumption was C = 600 L y[sup [minus]1]. These figures were compared with measured values of [sup 125]I activities in 42 thyroids taken at necropsy from residents in the North Surrey area who were dying during this same time period. Eight thyroids (19%) had measured activities greater than predicted, so they were named the self-defining critical group. After comparing the thyroid with the drinking water activity, the current generalized derived limit for [sup 125]I in the drinking water may be too high by a factor of 2. The reason for this appears to be the use of f = 0.3 which is the mean value for the normal' population. Models involving critical groups should use values of parameters different from the mean. In the present case, making f = 0.6 would remove the discrepancy between measurement and prediction and would be in reasonable accord with measured distributions of f.

  15. Ensemble Input of Group III/IV Muscle Afferents to CNS: A Limiting Factor of Central Motor Drive During Endurance Exercise from Normoxia to Moderate Hypoxia.

    PubMed

    Amann, Markus; Dempsey, Jerome A

    2016-01-01

    We recently hypothesized that across the range of normoxia to severe hypoxia the major determinant of central motor drive (CMD) during endurance exercise switches from a predominantly peripheral origin to a hypoxic-sensitive central component of fatigue. We found that peripheral locomotor muscle fatigue (pLMF) is the prevailing factor limiting central motor drive and therefore exercise performance from normoxia to moderate hypoxia (SaO2 > 75 %). In these levels of arterial hypoxemia, the development of pLMF is confined to a certain limit which varies between humans-pLMF does not develop to this limit in more severe hypoxia (SaO2 < 70 %) and exercise is prematurely terminated presumably to protect the brain from insufficient O2 supply. Based on the observations from normoxia to moderate hypoxia, we outlined a model suggesting that group III/IV muscle afferents impose inhibitory influences on the determination of CMD of working humans during high-intensity endurance exercise with the purpose to regulate and restrict the level of exercise-induced pLMF to an "individual critical threshold." To experimentally test this model, we pharmacologically blocked somatosensory pathways originating in the working limbs during cycling exercise in normoxia. After initial difficulties with a local anesthetic (epidural lidocaine, L3-L4) and associated loss of locomotor muscle strength we switched to an intrathecally applied opioid analgesic (fentanyl, L3-L4). These experiments were the first ever to selectively block locomotor muscle afferents during high-intensity cycling exercise without affecting maximal locomotor muscle strength. In the absence of opioid-mediated neural feedback from the working limbs, CMD was increased and end-exercise pLMF substantially exceeded, for the first time, the individual critical threshold of peripheral fatigue. The outcome of these studies confirm our hypothesis claiming that afferent feedback inhibits CMD and restricts the development of

  16. 1.99 Ga mafic dykes of the Lewisian Gneiss Complex of Scotland: An upper age limit for the Palaeoproterozoic Loch Maree Group

    NASA Astrophysics Data System (ADS)

    Baker, Thomas; Prave, Tony; Spencer, Christopher

    2015-04-01

    Mafic dyke swarms are often used as geochronological markers, as they are widespread and emplaced over short timespans. The ca. 2.4 Ga Scourie dyke swarm is one such example that has played a key role in understanding the complex tectonic and metamorphic history of the Lewisian Gneiss Complex of Scotland (LGC), part of the North Atlantic Craton (NAC). The LGC consists of Archean and Palaeoproterozoic terranes that experienced polyphase deformation prior to their assembly at ca. 1.8 Ga. Zircons separated from a doleritic dyke from the Gairloch terrane have yielded a concordant U-Th-Pb age (1,989 +4.3 / -0.99 Ma) using the ID-TIMS method. The doleritic dyke is emplaced in Lewisian gneiss that experienced both granulite and amphibolite-facies metamorphism. Partial recrystallisation and amphibolitisation of the dyke demonstrate that it pre-dates the most recent (Laxfordian) amphibolite-facies metamorphic event. The age obtained from the dyke overlaps the U-Pb age of a previously dated olivine gabbro dyke from the Assynt terrane (1,992 Ma). These combined ages provide strong corroborating evidence for a ca. 2.0 Ga mafic dyke swarm event, distinct from the older ca. 2.4 Ga Scourie dyke event known from elsewhere in the LGC. The existence of a ca. 2.0 Ga mafic dyke swarm provides an upper age limit for the Loch Maree Group (LMG), a Palaeoproterozoic succession of metasediment and metavolcanic rocks that overlie the LGC and which are not cross-cut by the Scourie dykes. This study proposes that a period of crustal extension took place in the region at ca. 2.0 Ga. Later, subduction may have resulted in the accretion of the LMG and the adjacent Ard Gneiss, which has previously been regarded as a magmatic arc. The ca. 1.9 Ga age of the earliest stage of the Laxfordian metamorphic event, which affected the LMG, could therefore mark the onset of collision. This sequence of events can be correlated with other coeval areas of the NAC, including the Nagssugtoqidian mobile belt of

  17. buffer Layer Growth, the Thickness Dependence of Jc in Coated Conductors, Local Identification of Current Limiting Mechanisms and Participation in the Wire Development Group

    SciTech Connect

    Larbalestier, David; Hellstron, Eric; Abraimov, Dmytro

    2011-12-17

    The primary thrusts of our work were to provide critical understanding of how best to enhance the current-carrying capacity of coated conductors. These include the deconstruction of Jc as a function of fim thickness, the growth of in situ films incorporating strong pinning centers and the use of a suite of position-sensitive tools that enable location and analysis of key areas where current-limiting occurs.

  18. Exploring the Limit of Accuracy of the Global Hybrid Meta Density Functional for Main-Group Thermochemistry, Kinetics, and Noncovalent Interactions

    SciTech Connect

    Zhao, Yan; Truhlar, Donald G.

    2008-11-11

    The hybrid meta density functionals M05-2X and M06-2X have been shown to provide broad accuracy for main group chemistry. In the present article we make the functional form more flexible and improve the self-interaction term in the correlation functional to improve its self-consistent-field convergence. We also explore the constraint of enforcing the exact forms of the exchange and correlation functionals through second order (SO) in the reduced density gradient. This yields two new functionals called M08-HX and M08-SO, with different exact constraints. The new functionals are optimized against 267 diverse main-group energetic data consisting of atomization energies, ionization potentials, electron affinities, proton affinities, dissociation energies, isomerization energies, barrier heights, noncovalent complexation energies, and atomic energies. Then the M08-HX, M08-SO, M05-2X, and M06-2X functionals and the popular B3LYP functional are tested against 250 data that were not part of the original training data for any of the functionals, in particular 164 main-group energetic data in 7 databases, 39 bond lengths, 38 vibrational frequencies, and 9 multiplicity-changing electronic transition energies. These tests include a variety of new challenges for complex systems, including large-molecule atomization energies, organic isomerization energies, interaction energies in uracil trimers, and bond distances in crowded molecules (in particular, cyclophanes). The M08-HX functional performs slightly better than M08-SO and M06-2X on average, significantly better than M05- 2X, and much better than B3LYP for a combination of main-group thermochemistry, kinetics, noncovalent interactions, and electronic spectroscopy. More important than the slight improvement in accuracy afforded by M08-HX is the conformation that the optimization procedure works well for data outside the training set. Problems for which the accuracy is especially improved by the new M08-HX functional include

  19. Analysis of operational, institutional and international limitations for alternative fuel vehicles and technologies: Means/methods for implementing changes. [Public fleet groups--information needs

    SciTech Connect

    Not Available

    1992-07-01

    This project focused upon the development of an approach to assist public fleet managers in evaluating the characteristics and availability of alternative fuels (AF's) and alternative fuel vehicles (AFV's) that will serve as possible replacements for vehicles currently serving the needs of various public entities. Also of concern were the institutional/international limitations for alternative fuels and alternative fuel vehicles. The City of Detroit and other public agencies in the Detroit area were the particular focus for the activities. As the development and initial stages of use of alternative fuels and alternative fuel vehicles proceeds, there will be an increasing need to provide information and guidance to decision-makers regarding differences in requirements and features of these fuels and vehicles. There wig be true differences in requirements for servicing, managing, and regulating. There will also be misunderstanding and misperception. There have been volumes of data collected on AFV'S, and as technology is improved, new data is constantly added. There are not, however, condensed and effective sources of information for public vehicle fleet managers on vehicle and equipment sources, characteristics, performance, costs, and environmental benefits. While theoretical modeling of public fleet requirements has been done, there do not seem to be readily available practical''. There is a need to provide the best possible information and means to minimize the problems for introducing the effective use of alternative fuels and alternative fuel vehicles.

  20. Transient inhibition of ROR-γt therapeutically limits intestinal inflammation by reducing TH17 cells and preserving group 3 innate lymphoid cells.

    PubMed

    Withers, David R; Hepworth, Matthew R; Wang, Xinxin; Mackley, Emma C; Halford, Emily E; Dutton, Emma E; Marriott, Clare L; Brucklacher-Waldert, Verena; Veldhoen, Marc; Kelsen, Judith; Baldassano, Robert N; Sonnenberg, Gregory F

    2016-03-01

    RAR-related orphan receptor-γt (ROR-γt) directs differentiation of proinflammatory T helper 17 (TH17) cells and is a potential therapeutic target in chronic autoimmune and inflammatory diseases. However, ROR-γt-dependent group 3 innate lymphoid cells ILC3s provide essential immunity and tissue protection in the intestine, suggesting that targeting ROR-γt could also result in impaired host defense after infection or enhanced tissue damage. Here, we demonstrate that transient chemical inhibition of ROR-γt in mice selectively reduces cytokine production from TH17 but not ILCs in the context of intestinal infection with Citrobacter rodentium, resulting in preserved innate immunity. Temporal deletion of Rorc (encoding ROR-γt) in mature ILCs also did not impair cytokine response in the steady state or during infection. Finally, pharmacologic inhibition of ROR-γt provided therapeutic benefit in mouse models of intestinal inflammation and reduced the frequency of TH17 cells but not ILCs isolated from primary intestinal samples of individuals with inflammatory bowel disease (IBD). Collectively, these results reveal differential requirements for ROR-γt in the maintenance of TH17 cell and ILC3 responses and suggest that transient inhibition of ROR-γt is a safe and effective therapeutic approach during intestinal inflammation.

  1. Cryptic diversity among Western Palearctic tree frogs: postglacial range expansion, range limits, and secondary contacts of three European tree frog lineages (Hyla arborea group).

    PubMed

    Stöck, Matthias; Dufresnes, Christophe; Litvinchuk, Spartak N; Lymberakis, Petros; Biollay, Sébastien; Berroneau, Matthieu; Borzée, Amaël; Ghali, Karim; Ogielska, Maria; Perrin, Nicolas

    2012-10-01

    We characterize divergence times, intraspecific diversity and distributions for recently recognized lineages within the Hyla arborea species group, based on mitochondrial and nuclear sequences from 160 localities spanning its whole distribution. Lineages of H. arborea, H. orientalis, H. molleri have at least Pliocene age, supporting species level divergence. The genetically uniform Iberian H. molleri, although largely isolated by the Pyrenees, is parapatric to H. arborea, with evidence for successful hybridization in a small Aquitanian corridor (southwestern France), where the distribution also overlaps with H. meridionalis. The genetically uniform H. arborea, spread from Crete to Brittany, exhibits molecular signatures of a postglacial range expansion. It meets different mtDNA clades of H. orientalis in NE-Greece, along the Carpathians, and in Poland along the Vistula River (there including hybridization). The East-European H. orientalis is strongly structured genetically. Five geographic mitochondrial clades are recognized, with a molecular signature of postglacial range expansions for the clade that reached the most northern latitudes. Hybridization with H. savignyi is suggested in southwestern Turkey. Thus, cryptic diversity in these Pliocene Hyla lineages covers three extremes: a genetically poor, quasi-Iberian endemic (H. molleri), a more uniform species distributed from the Balkans to Western Europe (H. arborea), and a well-structured Asia Minor-Eastern European species (H. orientalis). PMID:22652054

  2. Further Constraints on Galactic Coronal Models of BATSE Gamma-Ray Bursts: (1) Limits on Local Group Member Contributions, and (2) Implications for Spiral Arm Plus Coronal Distributions

    NASA Astrophysics Data System (ADS)

    Hakkila, J.; Meegan, C. A.; Horack, J. M.; Fishman, G. J.; Pendleton, G. N.; Wilson, R. B.; Brock, M. N.; Paciesas, W. S.; Briggs, M. S.

    1994-05-01

    Galactic coronal/extended halo models of gamma-ray burst spatial distributions and luminosity functions are analyzed and compared to BATSE observations using techniques described in Hakkila et al. (1994a, ApJ 422, 664) and Hakkila et al. (1994b, Proc. 1993 Hunts. Workshop). Local Group Galaxies other than the Milky Way and M31 do not appear able to contribute significantly in any coronal/extended halo scenario, as they would (1) raise the overall of the sample, and (2) show up in the two-point angular correlation function. Also, Galactic spiral arm/disk populations have been combined with coronal/extended halo populations to determine the extent to which they can be added without severely affecting sample isotropy. The models favor very low-luminosity spiral arm bursts (those that are so close that no spiral structure is noticeable) and/or small observed numbers of such bursts (less than 20% of the BATSE sample), while simultaneously constraining the spatial and luminosity properties of the coronal/extended halo population. This work has been supported by NASA grants NAG8-192 and NRA 92-OSSA-17.

  3. Genetic Analysis of the Aspergillus flavus Vegetative Compatibility Group to Which a Biological Control Agent That Limits Aflatoxin Contamination in U.S. Crops Belongs

    PubMed Central

    Cotty, Peter J.

    2015-01-01

    Some filamentous fungi in Aspergillus section Flavi produce carcinogenic secondary compounds called aflatoxins. Aflatoxin contamination is routinely managed in commercial agriculture with strains of Aspergillus flavus that do not produce aflatoxins. These non-aflatoxin-producing strains competitively exclude aflatoxin producers and reshape fungal communities so that strains with the aflatoxin-producing phenotype are less frequent. This study evaluated the genetic variation within naturally occurring atoxigenic A. flavus strains from the endemic vegetative compatibility group (VCG) YV36. AF36 is a strain of VCG YV36 and was the first fungus used in agriculture for aflatoxin management. Genetic analyses based on mating-type loci, 21 microsatellite loci, and a single nucleotide polymorphism (SNP) in the aflC gene were applied to a set of 237 YV36 isolates collected from 1990 through 2005 from desert legumes and untreated fields and from fields previously treated with AF36 across the southern United States. One haplotype dominated across time and space. No recombination with strains belonging to VCGs other than YV36 was detected. All YV36 isolates carried the SNP in aflC that prevents aflatoxin biosynthesis and the mat1-2 idiomorph at the mating-type locus. These results suggest that VCG YV36 has a clonal population structure maintained across both time and space. These results demonstrate the genetic stability of atoxigenic strains belonging to a broadly distributed endemic VCG in both untreated populations and populations where the short-term frequency of VCG YV36 has increased due to applications of a strain used to competitively exclude aflatoxin producers. This work supports the hypothesis that strains of this VCG are not involved in routine genetic exchange with aflatoxin-producing strains. PMID:26092465

  4. Real-Time Pretreatment Review Limits Unacceptable Deviations on a Cooperative Group Radiation Therapy Technique Trial: Quality Assurance Results of RTOG 0933

    SciTech Connect

    Gondi, Vinai; Cui, Yunfeng; Mehta, Minesh P.; Manfredi, Denise; Xiao, Ying; Galvin, James M.; Rowley, Howard; Tome, Wolfgang A.

    2015-03-01

    cases passed the pre-enrollment credentialing, the pretreatment centralized review disqualified 5.7% of reviewed cases, prevented unacceptable deviations in 24% of reviewed cases, and limited the final unacceptable deviation rate to 5%. Thus, pretreatment review is deemed necessary in future hippocampal avoidance trials and is potentially useful in other similarly challenging radiation therapy technique trials.

  5. Gestalt Interactional Groups

    ERIC Educational Resources Information Center

    Harman, Robert L.; Franklin, Richard W.

    1975-01-01

    Gestalt therapy in groups is not limited to individual work in the presence of an audience. Describes several ways to involve gestalt groups interactionally. Interactions described focus on learning by doing and discovering, and are noninterpretive. (Author/EJT)

  6. Current limiters

    SciTech Connect

    Loescher, D.H.; Noren, K.

    1996-09-01

    The current that flows between the electrical test equipment and the nuclear explosive must be limited to safe levels during electrical tests conducted on nuclear explosives at the DOE Pantex facility. The safest way to limit the current is to use batteries that can provide only acceptably low current into a short circuit; unfortunately this is not always possible. When it is not possible, current limiters, along with other design features, are used to limit the current. Three types of current limiters, the fuse blower, the resistor limiter, and the MOSFET-pass-transistor limiters, are used extensively in Pantex test equipment. Detailed failure mode and effects analyses were conducted on these limiters. Two other types of limiters were also analyzed. It was found that there is no best type of limiter that should be used in all applications. The fuse blower has advantages when many circuits must be monitored, a low insertion voltage drop is important, and size and weight must be kept low. However, this limiter has many failure modes that can lead to the loss of over current protection. The resistor limiter is simple and inexpensive, but is normally usable only on circuits for which the nominal current is less than a few tens of milliamperes. The MOSFET limiter can be used on high current circuits, but it has a number of single point failure modes that can lead to a loss of protective action. Because bad component placement or poor wire routing can defeat any limiter, placement and routing must be designed carefully and documented thoroughly.

  7. Non-specific bronchial hyper-responsiveness in children with allergic rhinitis: relationship with the atopic status.

    PubMed

    Cuttitta, Giuseppina; Cibella, Fabio; La Grutta, Stefania; Hopps, Maria R; Bucchieri, Salvatore; Passalacqua, Giovanni; Bonsignore, Giovanni

    2003-12-01

    An increased prevalence of bronchial hyper-responsiveness (BHR) has been demonstrated in children from a general population, and in non-asthmatic adults with allergic rhinitis. Thus, also children with allergic rhinitis are expected to be at higher risk of BHR. We evaluated the prevalence of BHR in a sample of non-asthmatic children with allergic rhinitis by means of the methacholine (Mch) bronchial challenge, and by monitorizing the airway patency using the daily peak expiratory flow variability (PEFv). Fifty-one children (ranged 6-15 years of age) with allergic rhinitis, ascertained by skin prick test to inhalant allergens, underwent a 14-day peak expiratory flow monitoring, and a Mch bronchial provocation challenge. Thirty healthy children matched for age, and sex served as control group. Thirty-one children in the rhinitis group (61%), and six (20%) in the control group were Mch+ (Mch provocative dose causing a 20% fall of forced expiratory volume in 1 s respect to baseline <2250 microg, equivalent to 11.50 micromol). In rhinitic children the PEFv did not significantly differ between Mch+ and Mch- subjects, but the total serum immunoglobulin E (IgE) were higher among Mch+. The persistent form of rhinitis was significantly associated to Mch positivity. Non-asthmatic children with allergic rhinitis displayed a high prevalence of BHR. The BHR was significantly associated with persistent rhinitis and with higher total IgE levels. Nevertheless, the spontaneous changes in airway patency, as expressed by PEFv, were within normal limits both in Mch+ and Mch- children.

  8. Training Groups, Encounter Groups, Sensitivity Groups and Group Psychotherapy

    PubMed Central

    Gottschalk, Louis A.; Pattison, E. Mansell; Schafer, Donald W.

    1971-01-01

    Descriptions and comparison of group therapies and the new group procedures (training groups and sensitivity groups—an outgrowth of the so-called Laboratory Movement methods of the mid-1930's) have been provided for the better understanding of non-psychiatric physicians. A group leader must have proper training and must help his group in its search for its avowed goals, whether he is a group therapist, a sensitivity trainer, or anyone else interested in utilizing group processes. Those goals are either the therapeutic benefit of the individual, as defined in group psychotherapy, or a better understanding of how one functions in groups, as in T-groups or the other group processes in the area of sensitive living. All group situations contain powerful tools which must be handled with proper respect. When so handled by experienced leaders, the individuals involved can achieve their goals in these group experiences. PMID:18730582

  9. Effect and mechanism of Bushen Huoxue recipe on ovarian reserve in mice with premature ovarian failure.

    PubMed

    Song, Kun-Kun; Ma, Wen-Wen; Huang, Cong; Ding, Jia-Hui; Cui, Dan-Dan; Tan, Xiu-Juan; Xiao, Jing; Zhang, Ming-Min

    2016-08-01

    The aim of the present study was to explore the effect and mechanism of Bushen Huoxue recipe (BHR) on ovarian reserve in mice with premature ovarian failure (POF). Mice were divided into 3 groups: normal group, model group and BHR group. Intraperitoneal injection of cyclophosphamide was performed to create the POF model. Primordial follicular (PDF) number, ovarian wet weight, ovarian index, and estrous cycle were analyzed to evaluate the effect of BHR on POF. Meanwhile, the mRNA and protein level of Mouse Vasa Homologue (MVH) in the bone marrow, peripheral blood and ovary were detected, to explore the underlying mechanism of the treatment efficacy of BHR on ovarian reserve. By the time of BHR treatment for 28 days, BHR increased the PDF number and shortened the estrous cycle of POF mice. BHR also decreased the mRNA level of MVH in the bone marrow, and increased mRNA and protein level of MVH in the ovary of POF mice. Our results demonstrated a treatment efficacy of BHR on POF mice, and revealed that BHR might repair the dysfunction of germline stem cells in the bone marrow, and thus to improve the ovarian reserve and enhance the ovarian function of POF mice through neo-oogenesis. PMID:27465335

  10. Group Counseling

    ERIC Educational Resources Information Center

    Mahler, Clarence A.

    1971-01-01

    This article reviews the major concerns of group counseling and differentiates among group guidance, group counseling, and group therapy. It also evaluates the research status of group counseling and presents implications for the future of this approach. Comment by Carl E. Thoresen follows. (Author)

  11. Grouping for Inequity

    ERIC Educational Resources Information Center

    Macqueen, Suzanne Elizabeth

    2013-01-01

    The inequity of streaming as a method of organising classes was established by research conducted in the 1960s and 1970s. While the practice produces small advantages for limited groups of students, it hinders the academic and social advancement of the majority. Although streaming has declined, new forms of achievement grouping have emerged, with…

  12. Group X

    SciTech Connect

    Fields, Susannah

    2007-08-16

    This project is currently under contract for research through the Department of Homeland Security until 2011. The group I was responsible for studying has to remain confidential so as not to affect the current project. All dates, reference links and authors, and other distinguishing characteristics of the original group have been removed from this report. All references to the name of this group or the individual splinter groups has been changed to 'Group X'. I have been collecting texts from a variety of sources intended for the use of recruiting and radicalizing members for Group X splinter groups for the purpose of researching the motivation and intent of leaders of those groups and their influence over the likelihood of group radicalization. This work included visiting many Group X websites to find information on splinter group leaders and finding their statements to new and old members. This proved difficult because the splinter groups of Group X are united in beliefs, but differ in public opinion. They are eager to tear each other down, prove their superiority, and yet remain anonymous. After a few weeks of intense searching, a list of eight recruiting texts and eight radicalizing texts from a variety of Group X leaders were compiled.

  13. Group Flow and Group Genius

    ERIC Educational Resources Information Center

    Sawyer, Keith

    2015-01-01

    Keith Sawyer views the spontaneous collaboration of group creativity and improvisation actions as "group flow," which organizations can use to function at optimum levels. Sawyer establishes ideal conditions for group flow: group goals, close listening, complete concentration, being in control, blending egos, equal participation, knowing…

  14. Isopermutation group

    SciTech Connect

    Muktibodh, A. S.

    2015-03-10

    The concept of ‘Isotopy’ as formulated by Ruggero Maria Santilli [1, 2, 3] plays a vital role in the development of Iso mathematics. Santilli defined iso-fields of characteristic zero. In this paper we extend this definition to define Iso-Galois fields [4] which are essentially of non-zero characteristic. Isotopically isomorphic realizations of a group define isopermutation group which gives a clear cut distinction between automorphic groups and isotopic groups.

  15. Hot Groups.

    ERIC Educational Resources Information Center

    Vail, Kathleen

    1996-01-01

    Collaborators sparked by creative ideas and obsessed by a common task may not realize they're part of a "hot group"--a term coined by business professors Harold J. Leavitt and Jean Lipman-Blumen. Spawned by group decision making and employee empowerment, hot groups can flourish in education settings. They're typically small, short lived, and goal…

  16. Galaxy groups

    SciTech Connect

    Brent Tully, R.

    2015-02-01

    Galaxy groups can be characterized by the radius of decoupling from cosmic expansion, the radius of the caustic of second turnaround, and the velocity dispersion of galaxies within this latter radius. These parameters can be a challenge to measure, especially for small groups with few members. In this study, results are gathered pertaining to particularly well-studied groups over four decades in group mass. Scaling relations anticipated from theory are demonstrated and coefficients of the relationships are specified. There is an update of the relationship between light and mass for groups, confirming that groups with mass of a few times 10{sup 12}M{sub ⊙} are the most lit up while groups with more and less mass are darker. It is demonstrated that there is an interesting one-to-one correlation between the number of dwarf satellites in a group and the group mass. There is the suggestion that small variations in the slope of the luminosity function in groups are caused by the degree of depletion of intermediate luminosity systems rather than variations in the number per unit mass of dwarfs. Finally, returning to the characteristic radii of groups, the ratio of first to second turnaround depends on the dark matter and dark energy content of the universe and a crude estimate can be made from the current observations of Ω{sub matter}∼0.15 in a flat topology, with a 68% probability of being less than 0.44.

  17. GROUP INEQUALITY

    PubMed Central

    Bowles, Samuel; Loury, Glenn C.; Sethi, Rajiv

    2014-01-01

    We explore the combined effect of segregation in social networks, peer effects, and the relative size of a historically disadvantaged group on the incentives to invest in market-rewarded skills and the dynamics of inequality between social groups. We identify conditions under which group inequality will persist in the absence of differences in ability, credit constraints, or labor market discrimination. Under these conditions, group inequality may be amplified even if initial group differences are negligible. Increases in social integration may destabilize an unequal state and make group equality possible, but the distributional and human capital effects of this depend on the demographic composition of the population. When the size of the initially disadvantaged group is sufficiently small, integration can lower the long-run costs of human capital investment in both groups and result in an increase the aggregate skill share. In contrast, when the initially disadvantaged group is large, integration can induce a fall in the aggregate skill share as the costs of human capital investment rise in both groups. We consider applications to concrete cases and policy implications. PMID:25554727

  18. New Perspectives on Structured Life Education Groups.

    ERIC Educational Resources Information Center

    Apgar, Kathryn; Coplon, Jennifer Kane

    1985-01-01

    Defines life education groups as educational, time-limited groups focusing on family and personal growth issues. Discusses the conceptual framework of the groups, the value of structure, prevention and intervention, and responding to the needs of diverse groups. (JAC)

  19. (Limiting the greenhouse effect)

    SciTech Connect

    Rayner, S.

    1991-01-07

    Traveler attended the Dahlem Research Conference organized by the Freien Universitat, Berlin. The subject of the conference was Limiting the Greenhouse Effect: Options for Controlling Atmospheric CO{sub 2} Accumulation. Like all Dahlem workshops, this was a meeting of scientific experts, although the disciplines represented were broader than usual, ranging across anthropology, economics, international relations, forestry, engineering, and atmospheric chemistry. Participation by scientists from developing countries was limited. The conference was divided into four multidisciplinary working groups. Traveler acted as moderator for Group 3 which examined the question What knowledge is required to tackle the principal social and institutional barriers to reducing CO{sub 2} emissions'' The working rapporteur was Jesse Ausubel of Rockefeller University. Other working groups examined the economic costs, benefits, and technical feasibility of options to reduce emissions per unit of energy service; the options for reducing energy use per unit of GNP; and the significant of linkage between strategies to reduce CO{sub 2} emissions and other goals. Draft reports of the working groups are appended. Overall, the conference identified a number of important research needs in all four areas. It may prove particularly important in bringing the social and institutional research needs relevant to climate change closer to the forefront of the scientific and policy communities than hitherto.

  20. Phase I North Central Cancer Treatment Group Trial-N9923 of escalating doses of twice-daily thoracic radiation therapy with amifostine and with alternating chemotherapy in limited stage small-cell lung cancer

    SciTech Connect

    Garces, Yolanda I. . E-mail: garces.yolanda@Mayo.edu; Okuno, Scott H.; Schild, Steven E.; Mandrekar, Sumithra J.; Bot, Brian M.; Martens, John M.; Wender, Donald B.; Soori, Gamini S.; Moore, Dennis F.; Kozelsky, Timothy F.; Jett, James R.

    2007-03-15

    Purpose: The primary goal was to identify the maximum tolerable dose (MTD) of thoracic radiation therapy (TRT) that can be given with chemotherapy and amifostine for patients with limited-stage small-cell lung cancer (LSCLC). Methods and Materials: Treatment began with two cycles of topotecan (1 mg/m{sup 2}) Days 1 to 5 and paclitaxel (175 mg/m{sup 2}) Day 5 (every 3 weeks) given before and after TRT. The TRT began at 6 weeks. The TRT was given in 120 cGy fractions b.i.d. and the dose escalation (from 4,800 cGy, dose level 1, to 6,600 cGy, dose level 4) followed the standard 'cohorts of 3' design. The etoposide (E) (50 mg/day) and cisplatin (C) (3 mg/m{sup 2}) were given i.v. before the morning TRT and amifostine (500 mg/day) was given before the afternoon RT. This was followed by prophylactic cranial irradiation (PCI). The dose-limiting toxicities (DLTs) were defined as Grade {>=}4 hematologic, febrile neutropenia, esophagitis, or other nonhematologic toxicity, Grade {>=}3 dyspnea, or Grade {>=}2 pneumonitis. Results: Fifteen patients were evaluable for the Phase I portion of the trial. No DLTs were seen at dose levels 1 and 2. Two patients on dose level 4 experienced DLTs: 1 patient had a Grade 4 pneumonitis, dyspnea, fatigue, hypokalemia, and anorexia, and 1 patient had a Grade 5 hypoxia attributable to TRT. One of 6 patients on dose level 3 had a DLT, Grade 3 esophagitis. The Grade {>=}3 toxicities seen in at least 10% of patients during TRT were esophagitis (53%), leukopenia (33%), dehydration (20%), neutropenia (13%), and fatigue (13%). The median survival was 14.5 months. Conclusion: The MTD of b.i.d. TRT was 6000 cGy (120 cGy b.i.d.) with EP and amifostine.

  1. Group Grammar

    ERIC Educational Resources Information Center

    Adams, Karen

    2015-01-01

    In this article Karen Adams demonstrates how to incorporate group grammar techniques into a classroom activity. In the activity, students practice using the target grammar to do something they naturally enjoy: learning about each other.

  2. Magnetostratigraphy of the Quebrada La Porcelana section, Sierra de Ramos, Salta Province, Argentina: age limits for the Neogene Orán Group and uplift of the southern Sierras Subandinas

    NASA Astrophysics Data System (ADS)

    Reynolds, J. H.; Hernández, R. M.; Galli, C. I.; Idleman, B. D.

    2001-12-01

    We present a magnetostratigraphic investigation of Neogene Orán Group strata at Quebrada La Porcelana. The area is located in the southern Sierras Subandinas of northwestern Argentina within the zone of 'normal' subduction. The oldest datable Neogene strata were deposited ˜8.1 Ma at the base of the Terciário Subandino. We estimate that the youngest strata are considerably younger than 1 m.y. The basal age is millions of years younger than lateral correlative units farther to the south in the Transition Zone. These chronostratigraphic results suggest that foreland thrusting was initiated much later in northernmost Argentina than it was in the Transition Zone. The data suggest that generation and migration of hydrocarbons from the Los Monos source horizon began about 3.8 Ma. Growth strata deposition began at ˜4.2 Ma, suggesting that trapping structures were available in the region when migration began.

  3. Group dynamics.

    PubMed

    Scandiffio, A L

    1990-12-01

    Group dynamics play a significant role within any organization, culture, or unit. The important thing to remember with any of these structures is that they are made up of people--people with different ideas, motivations, background, and sometimes different agendas. Most groups, formal or informal, look for a leader in an effort to maintain cohesiveness of the unit. At times, that cultural bond must be developed; once developed, it must be nurtured. There are also times that one of the group no longer finds the culture comfortable and begins to act out behaviorally. It is these times that become trying for the leader as she or he attempts to remain objective when that which was once in the building phase of group cohesiveness starts to fall apart. At all times, the manager must continue to view the employee creating the disturbance as an integral part of the group. It is at this time that it is beneficial to perceive the employee exhibiting problem behaviors as a special employee, as one who needs the benefit of your experience and skills, as one who is still part of the group. It is also during this time that the manager should focus upon her or his own views in the area of power, communication, and the corporate culture of the unit that one has established before attempting to understand another's point of view. Once we understand our own motivation and accept ourselves, it is then that we may move on to offer assistance to another. Once we understand our insecurities recognizing staff dysfunction as a symptom of system dysfunction will not be so threatening to the concept of the manager that we perceive ourselves to be. It takes a secure person to admit that she or he favors staff before deciding to do something to change things. The important thing to know is that it can be done. The favored staff can find a new way of relating to others, the special employee can find new modes of behavior (and even find self-esteem in the process), the group can find new ways

  4. Group key management

    SciTech Connect

    Dunigan, T.; Cao, C.

    1997-08-01

    This report describes an architecture and implementation for doing group key management over a data communications network. The architecture describes a protocol for establishing a shared encryption key among an authenticated and authorized collection of network entities. Group access requires one or more authorization certificates. The implementation includes a simple public key and certificate infrastructure. Multicast is used for some of the key management messages. An application programming interface multiplexes key management and user application messages. An implementation using the new IP security protocols is postulated. The architecture is compared with other group key management proposals, and the performance and the limitations of the implementation are described.

  5. Group Composition and Group Therapy for Complicated Grief

    ERIC Educational Resources Information Center

    Piper, William E.; Ogrodniczuk, John S.; Joyce, Anthony S.; Weideman, Rene; Rosie, John S.

    2007-01-01

    This prospective study investigated the impact of group composition on the outcome of 2 forms of time-limited, short-term group therapy (interpretive, supportive) with 110 outpatients from 18 therapy groups, who presented with complicated grief. The composition variable was based on the patient's level of quality of object relations. The higher…

  6. Group Learning.

    ERIC Educational Resources Information Center

    Black, Susan

    1992-01-01

    Research suggests that cooperative learning works best when students are first taught group-processing skills, such as leadership, decision making, communication, trust building, and conflict management. Inadequate teacher training and boring assignments can torpedo cooperative learning efforts. Administrators should reassure teachers with…

  7. Scope and limitation of organocuprates, and copper or nickel catalyst-modified Grignard reagents for installation of an alkyl group onto cis-4-cyclopentene-1,3-diol monoacetate.

    PubMed

    Ito, M; Matsuumi, M; Murugesh, M G; Kobayashi, Y

    2001-08-24

    Alkylation of the title compound 1 was investigated with two types of reagents. One is a copper reagent derived from R(T)MgX (X = Cl, Br) and CuX (X = CN, I) and the other is R(T)MgX in the presence of a copper or a nickel catalyst. First, butylation was studied with BuCu(CN)(MgX), Bu(2)Cu(CN)(MgX)(2), BuMgX/CuCN (10 mol %), BuCu (derived from BuMgCl and CuI), and BuMgCl/CuI (10 mol %) in THF or Et(2)O. We found that trans 1,4-isomer 2a and/or trans 1,2-isomer 3a were produced exclusively with these reagents and that the stoichiometry of BuMgX/CuX and the choice of solvent were critical to attain high regioselectivity and efficient yield. Reaction with Bu(2)Cu(CN)(MgCl)(2) and BuMgCl/CuX (X = CN, I; 10 mol %) both in THF produced 2a with 93-94% regioselectivity in 87-92% yields. On the other hand, BuCu(CN)(MgX) in THF, Bu(2)Cu(CN)(MgX)(2) in Et(2)O, and BuMgX/CuCN (10 mol %) in Et(2)O furnished 3a in good yields with >90% selectively, irrespective of X of BuMgX. In the nickel-catalyzed butylation of 1 with BuMgCl, NiCl(2)(dppp) among NiCl(2)(tpp)(2), NiCl(2)(dppf), and NiCl(2)(dppp) furnished the best result to produce 2a. The CuCN-based protocol was then applied to other alkyl Grignard reagents, which include Me, Et, (CH(2))(3)Ph, c-C(6)H(11), (CH(2))(6)OMOM, (CH(2))(9)CH=CH(2), and CH(2)Ph as the alkyl group (R(T)). In addition, the Mitsunobu inversion of 2a and 3a afforded the corresponding cis isomers stereoselectively with AcOH as an acid at -78 degrees C in toluene for 2a and with 4-(NO(2))C(6)H(4)COOH in THF at r.t. for 3a. No racemization during the alkylation was confirmed by the reaction using (1R,3S)-1 (>99% ee) to produce (1S,4S)-2a and (1S,2S)-3a, respectively.

  8. Local Group

    NASA Astrophysics Data System (ADS)

    Mateo, M.; Murdin, P.

    2000-11-01

    Not long after EDWIN HUBBLE established that galaxies are `island universes' similar to our home galaxy, the MILKY WAY, he realized that a few of these external galaxies are considerably closer to us than any others. In 1936 he first coined the term `Local Group' in his famous book The Realm of the Nebulae to identify our nearest galactic neighbors. More than 60 yr later, the galaxies of the Loca...

  9. Underrepresented groups

    NASA Technical Reports Server (NTRS)

    Peters, David A.

    1990-01-01

    The problem with the shortage of under represented groups in science and engineering is absolutely crucial, especially considering that U.S. will experience a shortage of 560,000 science and engineering personnel by the year 2010. Most studies by the National Science Foundation also concluded that projected shortages cannot be alleviated without significant increases in the involvement of Blacks, Hispanics, Native Americans, handicapped persons, and women.

  10. Cardiovascular group

    NASA Technical Reports Server (NTRS)

    Blomqvist, Gunnar

    1989-01-01

    As a starting point, the group defined a primary goal of maintaining in flight a level of systemic oxygen transport capacity comparable to each individual's preflight upright baseline. The goal of maintaining capacity at preflight levels would seem to be a reasonable objective for several different reasons, including the maintenance of good health in general and the preservation of sufficient cardiovascular reserve capacity to meet operational demands. It is also important not to introduce confounding variables in whatever other physiological studies are being performed. A change in the level of fitness is likely to be a significant confounding variable in the study of many organ systems. The principal component of the in-flight cardiovascular exercise program should be large-muscle activity such as treadmill exercise. It is desirable that at least one session per week be monitored to assure maintenance of proper functional levels and to provide guidance for any adjustments of the exercise prescription. Appropriate measurements include evaluation of the heart-rate/workload or the heart-rate/oxygen-uptake relationship. Respiratory gas analysis is helpful by providing better opportunities to document relative workload levels from analysis of the interrelationships among VO2, VCO2, and ventilation. The committee felt that there is no clear evidence that any particular in-flight exercise regimen is protective against orthostatic hypotension during the early readaptation phase. Some group members suggested that maintenance of the lower body muscle mass and muscle tone may be helpful. There is also evidence that late in-flight interventions to reexpand blood volume to preflight levels are helpful in preventing or minimizing postflight orthostatic hypotension.

  11. Radiosynthesis of [18F]Trifluoroalkyl Groups: Scope and Limitations

    PubMed Central

    Riss, P. J.

    2014-01-01

    The present paper is concerned with radiochemical methodology to furnish the trifluoromethyl motif labelled with 18F. Literature spanning the last four decades is comprehensively reviewed and radiochemical yields and specific activities are discussed. PMID:25110676

  12. Animal Welfare Groups Press for Limits on High School Research.

    ERIC Educational Resources Information Center

    BioScience, 1979

    1979-01-01

    Discussions from the conference on "The Use of Animals in High School Biology Classes" are highlighted in this article. The list of science fair rules, which resulted from the conference, is included. (SA)

  13. Group evaporation

    NASA Technical Reports Server (NTRS)

    Shen, Hayley H.

    1991-01-01

    Liquid fuel combustion process is greatly affected by the rate of droplet evaporation. The heat and mass exchanges between gas and liquid couple the dynamics of both phases in all aspects: mass, momentum, and energy. Correct prediction of the evaporation rate is therefore a key issue in engineering design of liquid combustion devices. Current analytical tools for characterizing the behavior of these devices are based on results from a single isolated droplet. Numerous experimental studies have challenged the applicability of these results in a dense spray. To account for the droplets' interaction in a dense spray, a number of theories have been developed in the past decade. Herein, two tasks are examined. One was to study how to implement the existing theoretical results, and the other was to explore the possibility of experimental verifications. The current theoretical results of group evaporation are given for a monodispersed cluster subject to adiabatic conditions. The time evolution of the fluid mechanic and thermodynamic behavior in this cluster is derived. The results given are not in the form of a subscale model for CFD codes.

  14. Innovative uses of psychodynamic group psychotherapy.

    PubMed

    Buchele, B J

    1994-01-01

    Psychodynamic group psychotherapy is gaining renewed attention as an effective form of treatment, due in part to increasing economic constraints that make other forms of treatment less accessible. The author highlights some innovative applications of both extended and time-limited groups. She also describes specific issues that can be addressed effectively in homogeneous time-limited group therapy.

  15. Value of bronchial challenge in scuba diving candidates.

    PubMed

    Badier, M; Guillot, C; Delpierre, S; Fornaris, E; Jacquin, M

    2000-12-01

    Bronchial challenges were effected with carbachol in 76 subjects who were candidates for a scuba diving group. Bronchial reactivity was assessed through airway resistance and forced expiratory volume in 1 sec (FEV1) measurements. Medical interrogation had revealed symptoms of recent (RA) or ancient (AA) asthma, or allergic rhinitis (AL). Nearly half of the subjects (47%) presented bronchial hyperresponsiveness (BHR), which was much more frequent in the RA group, but whose strength did not depend on clinical presentation. Prevalence of BHR was fairly high (36%) in the AL group. BHR constituted a contraindication to scuba diving because it may promote pulmonary barotrauma.

  16. Quantifying social group evolution

    NASA Astrophysics Data System (ADS)

    Palla, Gergely; Barabási, Albert-László; Vicsek, Tamás

    2007-04-01

    The rich set of interactions between individuals in society results in complex community structure, capturing highly connected circles of friends, families or professional cliques in a social network. Thanks to frequent changes in the activity and communication patterns of individuals, the associated social and communication network is subject to constant evolution. Our knowledge of the mechanisms governing the underlying community dynamics is limited, but is essential for a deeper understanding of the development and self-optimization of society as a whole. We have developed an algorithm based on clique percolation that allows us to investigate the time dependence of overlapping communities on a large scale, and thus uncover basic relationships characterizing community evolution. Our focus is on networks capturing the collaboration between scientists and the calls between mobile phone users. We find that large groups persist for longer if they are capable of dynamically altering their membership, suggesting that an ability to change the group composition results in better adaptability. The behaviour of small groups displays the opposite tendency-the condition for stability is that their composition remains unchanged. We also show that knowledge of the time commitment of members to a given community can be used for estimating the community's lifetime. These findings offer insight into the fundamental differences between the dynamics of small groups and large institutions.

  17. AO Group Annual Report

    SciTech Connect

    Olivier, S

    2005-10-04

    The Adaptive Optics (AO) Group in I Division develops and tests a broad range of advanced wavefront control technologies. Current applications focus on: Remote sensing, High power lasers, Astronomy, and Human vision. In the area of remote sensing, the AO Group leads a collaborative effort with LLNL's Nonproliferation, Arms Control & International Security (NAI) Directorate on Enhanced Surveillance Imaging. The ability to detect and identify individual people or vehicles from long-range is an important requirement for proliferation detection and homeland security. High-resolution imaging along horizontal paths through the atmosphere is limited by turbulence, which blurs and distorts the image. For ranges over {approx}one km, visible image resolution can be reduced by over an order of magnitude. We have developed an approach based on speckle imaging that can correct the turbulence-induced blurring and provide high resolution imagery. The system records a series of short exposure images which freeze the atmospheric effects. We can then estimate the image magnitude and phase using a bispectral estimation algorithm which cancels the atmospheric effects while maintaining object information at the diffraction limit of the imaging system.

  18. Genotype-related effect of crowding stress on blood pressure and vascular function in young female rats.

    PubMed

    Slezak, Peter; Puzserova, Angelika; Balis, Peter; Sestakova, Natalia; Majzunova, Miroslava; Dovinova, Ima; Kluknavsky, Michal; Bernatova, Iveta

    2014-01-01

    This study investigated the influence of chronic crowding stress on nitric oxide (NO) production, vascular function and oxidative status in young Wistar-Kyoto (WKY), borderline hypertensive (BHR) and spontaneously hypertensive (SHR) female rats. Five-week old rats were exposed to crowding for two weeks. Crowding elevated plasma corticosterone (P<0.05) and accelerated BP (P<0.01 versus basal) only in BHR. NO production and superoxide concentration were significantly higher in the aortas of control BHR and SHR versus WKY. Total acetylcholine (ACh)-induced relaxation in the femoral artery was reduced in control SHR versus WKY and BHR, and stress did not affect it significantly in any genotype. The attenuation of ACh-induced relaxation in SHR versus WKY was associated with reduction of its NO-independent component. Crowding elevated NO production in all strains investigated but superoxide concentration was increased only in WKY, which resulted in reduced NO-dependent relaxation in WKY. In crowded BHR and SHR, superoxide concentration was either unchanged or reduced, respectively, but NO-dependent relaxation was unchanged in both BHR and SHR versus their respective control group. This study points to genotype-related differences in stress vulnerability in young female rats. The most pronounced negative influence of stress was observed in BHR despite preserved endothelial function.

  19. 50 CFR 622.382 - Bag and possession limits.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) King and Spanish mackerel—(1) Bag limits. (i) Atlantic migratory group king mackerel— (A) Mid-Atlantic... does not exceed 5. (ii) Gulf migratory group king mackerel—2. (iii) Atlantic migratory group...

  20. An Adaptive TVD Limiter

    NASA Astrophysics Data System (ADS)

    Jeng, Yih Nen; Payne, Uon Jan

    1995-05-01

    An adaptive TVD limiter, based on a limiter approximating the upper boundary of the TVD range and that of the third-order upwind TVD scheme, is developed in this work. The limiter switches to the comprressive limiter near a discontinuity, to the third-order TVD scheme's limiter in the smooth region, and to a weighted averaged scheme in the transition region between smooth and high gradient solutions. Numerical experiments show that the proposed scheme works very well for one-dimensional scalar equation problems but becomes less effective in one- and two-dimensional Euler equation problems. Further study is required for the two-dimensional scalar equation problems.

  1. Group Work Publication-1991.

    ERIC Educational Resources Information Center

    Zimpfer, David G.

    1992-01-01

    Lists 21 new publications in group work, of which 9 are reviewed. Those discussed include publications on group counseling and psychotherapy, structured groups, support groups, psychodrama, and social group work. (Author/NB)

  2. Group Cohesion in Experiential Growth Groups

    ERIC Educational Resources Information Center

    Steen, Sam; Vasserman-Stokes, Elaina; Vannatta, Rachel

    2014-01-01

    This article explores the effect of web-based journaling on changes in group cohesion within experiential growth groups. Master's students were divided into 2 groups. Both used a web-based platform to journal after each session; however, only 1 of the groups was able to read each other's journals. Quantitative data collected before and…

  3. Group Therapy with Multiple Therapists in A Large Group.

    ERIC Educational Resources Information Center

    Herschleman, Philip; Freundlich, David

    The utilization of multiple therapists in large group therapy meetings has been found to be a significant improvement over the traditional ward meeting or patient-staff conference. The initially limited goals of reducing ward tension and acting out by means of patients ventilation were surpassed. Despite the size of the meetings it was often…

  4. Organocatalyzed Group Transfer Polymerization.

    PubMed

    Chen, Yougen; Kakuchi, Toyoji

    2016-08-01

    In contrast to the conventional group transfer polymerization (GTP) using a catalyst of either an anionic nucleophile or a transition-metal compound, the organocatalyzed GTP has to a great extent improved the living characteristics of the polymerization from the viewpoints of synthesizing structurally well-defined acrylic polymers and constructing defect-free polymer architectures. In this article, we describe the organocatalyzed GTP from a relatively personal perspective to provide our colleagues with a perspicuous and systematic overview on its recent progress as well as a reply to the curiosity of how excellently the organocatalysts have performed in this field. The stated perspectives of this review mainly cover five aspects, in terms of the assessment of the livingness of the polymerization, limit and scope of applicable monomers, mechanistic studies, control of the polymer structure, and a new GTP methodology involving the use of tris(pentafluorophenyl)borane and hydrosilane. PMID:27427399

  5. Working Group Report: Sensors

    SciTech Connect

    Artuso, M.; et al.,

    2013-10-18

    Sensors play a key role in detecting both charged particles and photons for all three frontiers in Particle Physics. The signals from an individual sensor that can be used include ionization deposited, phonons created, or light emitted from excitations of the material. The individual sensors are then typically arrayed for detection of individual particles or groups of particles. Mounting of new, ever higher performance experiments, often depend on advances in sensors in a range of performance characteristics. These performance metrics can include position resolution for passing particles, time resolution on particles impacting the sensor, and overall rate capabilities. In addition the feasible detector area and cost frequently provides a limit to what can be built and therefore is often another area where improvements are important. Finally, radiation tolerance is becoming a requirement in a broad array of devices. We present a status report on a broad category of sensors, including challenges for the future and work in progress to solve those challenges.

  6. TROPIX plasma interactions group report

    NASA Technical Reports Server (NTRS)

    Herr, Joel L.; Chock, Ricaurte

    1993-01-01

    The purpose is to summarize the spacecraft charging analysis conducted by the plasma interactions group during the period from April 1993 to July 1993, on the proposed TROPIX spacecraft, and to make design recommendations which will limit the detrimental effects introduced by spacecraft charging. The recommendations were presented to the TROPIX study team at a Technical Review meeting held on 15 July 1993.

  7. Detector limitations, STAR

    SciTech Connect

    Underwood, D. G.

    1998-07-13

    Every detector has limitations in terms of solid angle, particular technologies chosen, cracks due to mechanical structure, etc. If all of the presently planned parts of STAR [Solenoidal Tracker At RHIC] were in place, these factors would not seriously limit our ability to exploit the spin physics possible in RHIC. What is of greater concern at the moment is the construction schedule for components such as the Electromagnetic Calorimeters, and the limited funding for various levels of triggers.

  8. Systematics and limit calculations

    SciTech Connect

    Fisher, Wade; /Fermilab

    2006-12-01

    This note discusses the estimation of systematic uncertainties and their incorporation into upper limit calculations. Two different approaches to reducing systematics and their degrading impact on upper limits are introduced. An improved {chi}{sup 2} function is defined which is useful in comparing Poisson distributed data with models marginalized by systematic uncertainties. Also, a technique using profile likelihoods is introduced which provides a means of constraining the degrading impact of systematic uncertainties on limit calculations.

  9. Radiation sources working group summary

    SciTech Connect

    Fazio, M.V.

    1998-12-31

    The Radiation Sources Working Group addressed advanced concepts for the generation of RF energy to power advanced accelerators. The focus of the working group included advanced sources and technologies above 17 GHz. The topics discussed included RF sources above 17 GHz, pulse compression techniques to achieve extreme peak power levels, components technology, technology limitations and physical limits, and other advanced concepts. RF sources included gyroklystrons, magnicons, free-electron masers, two beam accelerators, and gyroharmonic and traveling wave devices. Technology components discussed included advanced cathodes and electron guns, high temperature superconductors for producing magnetic fields, RF breakdown physics and mitigation, and phenomena that impact source design such as fatigue in resonant structures due to RF heating. New approaches for RF source diagnostics located internal to the source were discussed for detecting plasma and beam phenomena existing in high energy density electrodynamic systems in order to help elucidate the reasons for performance limitations.

  10. Limits to Inclusion

    ERIC Educational Resources Information Center

    Hansen, Janne Hedegaard

    2012-01-01

    In this article, I will argue that a theoretical identification of the limit to inclusion is needed in the conceptual identification of inclusion. On the one hand, inclusion is formulated as a vision that is, in principle, limitless. On the other hand, there seems to be an agreement that inclusion has a limit in the pedagogical practice. However,…

  11. Dose limits for astronauts

    NASA Technical Reports Server (NTRS)

    Sinclair, W. K.

    2000-01-01

    Radiation exposures to individuals in space can greatly exceed natural radiation exposure on Earth and possibly normal occupational radiation exposures as well. Consequently, procedures limiting exposures would be necessary. Limitations were proposed by the Radiobiological Advisory Panel of the National Academy of Sciences/National Research Council in 1970. This panel recommended short-term limits to avoid deterministic effects and a single career limit (of 4 Sv) based on a doubling of the cancer risk in men aged 35 to 55. Later, when risk estimates for cancer had increased and were recognized to be age and sex dependent, the NCRP, in Report No. 98 in 1989, recommended a range of career limits based on age and sex from 1 to 4 Sv. NCRP is again in the process of revising recommendations for astronaut exposure, partly because risk estimates have increased further and partly to recognize trends in limiting radiation exposure occupationally on the ground. The result of these considerations is likely to be similar short-term limits for deterministic effects but modified career limits.

  12. Dose limits for astronauts.

    PubMed

    Sinclair, W K

    2000-11-01

    Radiation exposures to individuals in space can greatly exceed natural radiation exposure on Earth and possibly normal occupational radiation exposures as well. Consequently, procedures limiting exposures would be necessary. Limitations were proposed by the Radiobiological Advisory Panel of the National Academy of Sciences/National Research Council in 1970. This panel recommended short-term limits to avoid deterministic effects and a single career limit (of 4 Sv) based on a doubling of the cancer risk in men aged 35 to 55. Later, when risk estimates for cancer had increased and were recognized to be age and sex dependent, the NCRP, in Report No. 98 in 1989, recommended a range of career limits based on age and sex from 1 to 4 Sv. NCRP is again in the process of revising recommendations for astronaut exposure, partly because risk estimates have increased further and partly to recognize trends in limiting radiation exposure occupationally on the ground. The result of these considerations is likely to be similar short-term limits for deterministic effects but modified career limits. PMID:11045534

  13. Interagency mechanical operations group numerical systems group

    SciTech Connect

    1997-09-01

    This report consists of the minutes of the May 20-21, 1971 meeting of the Interagency Mechanical Operations Group (IMOG) Numerical Systems Group. This group looks at issues related to numerical control in the machining industry. Items discussed related to the use of CAD and CAM, EIA standards, data links, and numerical control.

  14. Group Dynamic Processes in Email Groups

    ERIC Educational Resources Information Center

    Alpay, Esat

    2005-01-01

    Discussion is given on the relevance of group dynamic processes in promoting decision-making in email discussion groups. General theories on social facilitation and social loafing are considered in the context of email groups, as well as the applicability of psychodynamic and interaction-based models. It is argued that such theories may indeed…

  15. Facilitating Reminiscence Groups: Perceptions of Group Leaders

    ERIC Educational Resources Information Center

    Christensen, Teresa M.; Hulse-Killacky, Diana; Salgado, Roy A.; Thornton, Mark D.; Miller, Jason L.

    2006-01-01

    This article presents the results of a two-year qualitative investigation in which group leaders provided their perceptions of the process of facilitating reminiscence groups with elderly persons in a residential care facility. Group Culture emerged as the dominant construct. Findings from this study can serve guide leaders who are interested in…

  16. Tokamak pump limiters

    NASA Astrophysics Data System (ADS)

    Conn, Robert W.

    1984-12-01

    Experiments with pump limiters on several operating tokamaks have established them as efficient collectors of particles. The gas pressure rise within the chamber behind the limiters has been as high as 50 mTorr when there is no internal chamber pumping. Observations of the plasma power distribution over the front face of these limiter modules yield estimates for the scale length of radial power decay consistent with predictions of relatively simple theory. Interaction of the in-flowing plasma with recycling neutral gas near the limiter deflector plate is predicted to become important when the effective ionization mean free path is comparable to or less than the neutral atom mean path length within the throat structure of the limiter. Recent experiments with a scoop limiter without active internal pumping have been carried out in the PDX tokamak with up to 6 MW of auxiliary neutral beam heating. Experiments have also been performed with a rotating head pump limiter in the PLT tokamak in conjunction with RF plasma heating. Extensive experiments have been done in the ISX-B tokamak and first experiments have been completed with the ALT-I limiter in TEXTOR. The pump limiter modules in these latter two machines have internal getter pumping. Experiments in ISX-B are with ohmic and auxiliary neutral beam heating. The results in ISX-B and TEXTOR show that active density control and particle removal is achieved with pump limiters. In ISX-B, the boundary layer (or scape-off layer) plasma partially screens the core plasma from gas injection. In both ISX-B and TEXTOR, the pressure internal to the module scales linearly with plasma density but in ISX-B, with neutral beam injection, a nonlinear increase is observed at the highest densities studied. Plasma plugging is the suspected cause. Results from PDX suggest that a regime may exist in which core plasma energy confinement improves using a pump limiter during neutral beam injection. Asymmetric radial profiles and an increased

  17. Characterizing limit order prices

    NASA Astrophysics Data System (ADS)

    Withanawasam, R. M.; Whigham, P. A.; Crack, Timothy Falcon

    2013-11-01

    A computational model of a limit order book is used to study the effect of different limit order distribution offsets. Reference prices such as same side/contra side best market prices and last traded price are considered in combination with different price offset distributions. We show that when characterizing limit order prices, varying the offset distribution only produces different behavior when the reference price is the contra side best price. Irrespective of the underlying mechanisms used in computing the limit order prices, the shape of the price graph and the behavior of the average order book profile distribution are strikingly similar in all the considered reference prices/offset distributions. This implies that existing averaging methods can cancel variabilities in limit order book shape/attributes and may be misleading.

  18. Immediate Effects of Bhramari Pranayama on Resting Cardiovascular Parameters in Healthy Adolescents

    PubMed Central

    Kamaldeen, Dilara; Pitani, Ravishankar; Amaldas, Julius

    2016-01-01

    Introduction In yoga, Pranayama has a very important role in maintaining sound health. There is some strong scientific basis on constant physiological changes produced when pranayama is practiced for long duration. Still, there exists a dearth of literature on the effect of Bhramari pranayama (Bhr.p) on physiological systems. Aim To assess the immediate effect of Bhramari pranayama (Bhr.P) practice on the resting cardiovascular parameters in healthy adolescents. Materials and Methods Sixty apparently healthy adolescents of both sex participated in the study. They were randomly divided into Bhr.P (n-30) and control (n-30) group. Informed consent was obtained after explaining the detailed procedure of the study. Bhr.P group practiced Bhramari pranayama for 45 min (5 cycles) and control group was allowed to do normal breathing (12-16 breath /min). Heart rate (HR) was assessed by radial artery palpation method and blood pressure was recorded in supine position after 5 minutes of rest by sphygmomanometer. Results The HR reduced significantly (p-0.001) in Bhr.P group. BP indices, Pulse Pressure (PP), Mean Arterial Pressure (MAP), Rate Pressure Product (RPP) and Double Product (DoP) significantly decreased after Bhr.p practice compared with control. Pre and Post inter group analysis also showed that significant reduction in HR and BP indices in Bhr.P group. Conclusion Present study showed that Bhr.P practice produces relaxed state and in this state parasympathetic activity overrides the sympathetic activity. It suggests that Bhramari pranayama improves the resting cardiovascular parameters in healthy adolescents. PMID:27437210

  19. Percentage of People with at Least One Activities of Daily Living (ADL) Limitation

    MedlinePlus

    ... ADL) Limitation Percentage of People with at Least One Activities of Daily Living (ADL) Limitation This measure ... Age Group Percentage of People with at Least One Activities of Daily Living Limitation by Age Group ...

  20. Optical limiting materials

    DOEpatents

    McBranch, Duncan W.; Mattes, Benjamin R.; Koskelo, Aaron C.; Heeger, Alan J.; Robinson, Jeanne M.; Smilowitz, Laura B.; Klimov, Victor I.; Cha, Myoungsik; Sariciftci, N. Serdar; Hummelen, Jan C.

    1998-01-01

    Optical limiting materials. Methanofullerenes, fulleroids and/or other fullerenes chemically altered for enhanced solubility, in liquid solution, and in solid blends with transparent glass (SiO.sub.2) gels or polymers, or semiconducting (conjugated) polymers, are shown to be useful as optical limiters (optical surge protectors). The nonlinear absorption is tunable such that the energy transmitted through such blends saturates at high input energy per pulse over a wide range of wavelengths from 400-1100 nm by selecting the host material for its absorption wavelength and ability to transfer the absorbed energy into the optical limiting composition dissolved therein. This phenomenon should be generalizable to other compositions than substituted fullerenes.

  1. CONTROL LIMITER DEVICE

    DOEpatents

    DeShong, J.A.

    1960-03-01

    A control-limiting device for monltoring a control system is described. The system comprises a conditionsensing device, a condition-varying device exerting a control over the condition, and a control means to actuate the condition-varying device. A control-limiting device integrates the total movement or other change of the condition-varying device over any interval of time during a continuum of overlapping periods of time, and if the tothl movement or change of the condition-varying device exceeds a preset value, the control- limiting device will switch the control of the operated apparatus from automatic to manual control.

  2. Force Limited Vibration Testing

    NASA Technical Reports Server (NTRS)

    Scharton, Terry; Chang, Kurng Y.

    2005-01-01

    This slide presentation reviews the concept and applications of Force Limited Vibration Testing. The goal of vibration testing of aerospace hardware is to identify problems that would result in flight failures. The commonly used aerospace vibration tests uses artificially high shaker forces and responses at the resonance frequencies of the test item. It has become common to limit the acceleration responses in the test to those predicted for the flight. This requires an analysis of the acceleration response, and requires placing accelerometers on the test item. With the advent of piezoelectric gages it has become possible to improve vibration testing. The basic equations have are reviewed. Force limits are analogous and complementary to the acceleration specifications used in conventional vibration testing. Just as the acceleration specification is the frequency spectrum envelope of the in-flight acceleration at the interface between the test item and flight mounting structure, the force limit is the envelope of the in-flight force at the interface . In force limited vibration tests, both the acceleration and force specifications are needed, and the force specification is generally based on and proportional to the acceleration specification. Therefore, force limiting does not compensate for errors in the development of the acceleration specification, e.g., too much conservatism or the lack thereof. These errors will carry over into the force specification. Since in-flight vibratory force data are scarce, force limits are often derived from coupled system analyses and impedance information obtained from measurements or finite element models (FEM). Fortunately, data on the interface forces between systems and components are now available from system acoustic and vibration tests of development test models and from a few flight experiments. Semi-empirical methods of predicting force limits are currently being developed on the basis of the limited flight and system test

  3. Novel limiter pump topologies

    SciTech Connect

    Schultz, J.H.

    1981-01-01

    The use of limiter pumps as the principle plasma exhaust system of a magnetic confinement fusion device promises significant simplification, when compared to previously investigating divertor based systems. Further simplifications, such as the integration of the exhaust system with a radio frequency heating system and with the main reactor shield and structure are investigated below. The integrity of limiters in a reactor environment is threatened by many mechanisms, the most severe of which may be erosion by sputtering. Two novel topolgies are suggested which allow high erosion without limiter failure.

  4. Controlling multiple groups of robots

    NASA Astrophysics Data System (ADS)

    Hor, MawKae

    1992-11-01

    Coordinating multiple robots has attracted researchers' interests for many years. However, most of the problems being studied deal with multiple robots acted only within a single group. Coordinated robots are categorized into different groups when the coordination involves robots interchange or heterogeneous motion during the manipulation process. In such a case, coordination between robot groups has to be considered. This is required in certain types of coordinated manipulations such as passing an object, held by multiple robots, between groups of robots or rotating or rolling an object, held by multiple robots, continuously. In the former task, coordinations are made between two isotropic groups of robots whereas in the latter task, coordinations are made between non-isotropic groups of robots. This paper investigates problems related to the control and coordinating of multiple groups of robots. We analyze various kind of tasks of these types and propose a hierarchical control mechanism in achieving these coordinations. Scenarios and limitations for these tasks are presented and discussed. A hybrid force and position control principle is employed in both global and local planning and control. A hierarchical architecture is used to control different levels of the control and planning primitives. The primitives developed for controlling individual robot group can be adopted in this architecture. The primitives in one level offer services only to those in its neighboring levels and hides them from the details of actual service implementations hence reducing the system designing complexity.

  5. The Globalization of Cooperative Groups.

    PubMed

    Valdivieso, Manuel; Corn, Benjamin W; Dancey, Janet E; Wickerham, D Lawrence; Horvath, L Elise; Perez, Edith A; Urton, Alison; Cronin, Walter M; Field, Erica; Lackey, Evonne; Blanke, Charles D

    2015-10-01

    The National Cancer Institute (NCI)-supported adult cooperative oncology research groups (now officially Network groups) have a longstanding history of participating in international collaborations throughout the world. Most frequently, the US-based cooperative groups work reciprocally with the Canadian national adult cancer clinical trial group, NCIC CTG (previously the National Cancer Institute of Canada Clinical Trials Group). Thus, Canada is the largest contributor to cooperative groups based in the United States, and vice versa. Although international collaborations have many benefits, they are most frequently utilized to enhance patient accrual to large phase III trials originating in the United States or Canada. Within the cooperative group setting, adequate attention has not been given to the study of cancers that are unique to countries outside the United States and Canada, such as those frequently associated with infections in Latin America, Asia, and Africa. Global collaborations are limited by a number of barriers, some of which are unique to the countries involved, while others are related to financial support and to US policies that restrict drug distribution outside the United States. This article serves to detail the cooperative group experience in international research and describe how international collaboration in cancer clinical trials is a promising and important area that requires greater consideration in the future. PMID:26433551

  6. The Globalization of Cooperative Groups.

    PubMed

    Valdivieso, Manuel; Corn, Benjamin W; Dancey, Janet E; Wickerham, D Lawrence; Horvath, L Elise; Perez, Edith A; Urton, Alison; Cronin, Walter M; Field, Erica; Lackey, Evonne; Blanke, Charles D

    2015-10-01

    The National Cancer Institute (NCI)-supported adult cooperative oncology research groups (now officially Network groups) have a longstanding history of participating in international collaborations throughout the world. Most frequently, the US-based cooperative groups work reciprocally with the Canadian national adult cancer clinical trial group, NCIC CTG (previously the National Cancer Institute of Canada Clinical Trials Group). Thus, Canada is the largest contributor to cooperative groups based in the United States, and vice versa. Although international collaborations have many benefits, they are most frequently utilized to enhance patient accrual to large phase III trials originating in the United States or Canada. Within the cooperative group setting, adequate attention has not been given to the study of cancers that are unique to countries outside the United States and Canada, such as those frequently associated with infections in Latin America, Asia, and Africa. Global collaborations are limited by a number of barriers, some of which are unique to the countries involved, while others are related to financial support and to US policies that restrict drug distribution outside the United States. This article serves to detail the cooperative group experience in international research and describe how international collaboration in cancer clinical trials is a promising and important area that requires greater consideration in the future.

  7. The Globalization of Cooperative Groups

    PubMed Central

    Valdivieso, Manuel; Corn, Benjamin W.; Dancey, Janet E.; Wickerham, D. Lawrence; Horvath, L. Elise; Perez, Edith A.; Urton, Alison; Cronin, Walter M.; Field, Erica; Lackey, Evonne; Blanke, Charles D.

    2015-01-01

    The National Cancer Institute-supported adult cooperative oncology research groups (now officially Network groups) have a long-standing history of participating in international collaborations throughout the world. Most frequently, the U.S. based cooperative groups work reciprocally with the Canadian national adult cancer clinical trial group, NCIC CTG (previously the National Cancer Institute of Canada Clinical Trials Group). Thus, Canada is the largest contributor to cooperative groups based in the U.S., and vice versa. Although international collaborations have many benefits, they are most frequently utilized to enhance patient accrual to large phase III trials originating in the U.S. or Canada. Within the cooperative group setting, adequate attention has not been given to the study of cancers that are unique to countries outside the U.S. and Canada, such as those frequently associated with infections in Latin America, Asia and Africa. Global collaborations are limited by a number of barriers, some of which are unique to the countries involved, while others are related to financial support and to U.S. policies that restrict drug distribution outside the U.S. This manuscript serves to detail the cooperative group experience in international research and describe how international collaboration in cancer clinical trials is a promising and important area that requires greater consideration in the future. PMID:26433551

  8. PLT rotating pumped limiter

    SciTech Connect

    Cohen, S.A.; Budny, R.V.; Corso, V.; Boychuck, J.; Grisham, L.; Heifetz, D.; Hosea, J.; Luyber, S.; Loprest, P.; Manos, D.

    1984-07-01

    A limiter with a specially contoured front face and the ability to rotate during tokamak discharges has been installed in a PLT pump duct. These features have been selected to handle the unique particle removal and heat load requirements of ICRF heating and lower-hybrid current-drive experiments. The limiter has been conditioned and commissioned in an ion-beam test stand by irradiation with 1 MW power, 200 ms duration beams of 40 keV hydrogen ions. Operation in PLT during ohmic discharges has proven the ability of the limiter to reduce localized heating caused by energetic electron bombardment and to remove about 2% of the ions lost to the PLT walls and limiters.

  9. PEAK LIMITING AMPLIFIER

    DOEpatents

    Goldsworthy, W.W.; Robinson, J.B.

    1959-03-31

    A peak voltage amplitude limiting system adapted for use with a cascade type amplifier is described. In its detailed aspects, the invention includes an amplifier having at least a first triode tube and a second triode tube, the cathode of the second tube being connected to the anode of the first tube. A peak limiter triode tube has its control grid coupled to thc anode of the second tube and its anode connected to the cathode of the second tube. The operation of the limiter is controlled by a bias voltage source connected to the control grid of the limiter tube and the output of the system is taken from the anode of the second tube.

  10. Primary Analysis of a Phase II Randomized Trial Radiation Therapy Oncology Group (RTOG) 0212: Impact of Different Total Doses and Schedules of Prophylactic Cranial Irradiation on Chronic Neurotoxicity and Quality of Life for Patients With Limited-Disease Small-Cell Lung Cancer

    SciTech Connect

    Wolfson, Aaron H.; Bae, Kyounghwa; Komaki, Ritsuko; Meyers, Christina; Movsas, Benjamin; Le Pechoux, Cecile; Werner-Wasik, Maria; Videtic, Gregory M.M.; Garces, Yolanda I.; Choy, Hak

    2011-09-01

    Purpose: To determine the effect of dose and fractionation schedule of prophylactic cranial irradiation (PCI) on the incidence of chronic neurotoxicity (CNt) and changes in quality of life for selected patients with limited-disease small-cell lung cancer (LD SCLC). Methods and Materials: Patients with LD SCLC who achieved a complete response after chemotherapy and thoracic irradiation were eligible for randomization to undergo PCI to a total dose of 25 Gy in 10 daily fractions (Arm 1) vs. the experimental cohort of 36 Gy. Those receiving 36 Gy underwent a secondary randomization between daily 18 fractions (Arm 2) and twice-daily 24 fractions (Arm 3). Enrolled patients participated in baseline and follow-up neuropsychological test batteries along with quality-of-life assessments. Results: A total of 265 patients were accrued, with 131 in Arm 1, 67 in Arm 2, and 66 in Arm 3 being eligible. There are 112 patients (42.2%) alive with 25.3 months of median follow-up. There were no significant baseline differences among groups regarding quality-of-life measures and one of the neuropsychological tests, namely the Hopkins Verbal Learning Test. However, at 12 months after PCI there was a significant increase in the occurrence of CNt in the 36-Gy cohort (p = 0.02). Logistic regression analysis revealed increasing age to be the most significant predictor of CNt (p = 0.005). Conclusions: Because of the increased risk of developing CNt in study patients with 36 Gy, a total PCI dose of 25 Gy remains the standard of care for patients with LD SCLC attaining a complete response to initial chemoradiation.

  11. Group Work: How to Use Groups Effectively

    ERIC Educational Resources Information Center

    Burke, Alison

    2011-01-01

    Many students cringe and groan when told that they will need to work in a group. However, group work has been found to be good for students and good for teachers. Employers want college graduates to have developed teamwork skills. Additionally, students who participate in collaborative learning get better grades, are more satisfied with their…

  12. MSUD Family Support Group

    MedlinePlus

    ... Group The MSUD Family Support Group is a non-profit 501 (c)(3) organization for those with MSUD ... Family Support Group is a 501(c)(3) non-profit organization with no paid staff. Funds are needed ...

  13. Optimal Limited Contingency Planning

    NASA Technical Reports Server (NTRS)

    Meuleau, Nicolas; Smith, David E.

    2003-01-01

    For a given problem, the optimal Markov policy over a finite horizon is a conditional plan containing a potentially large number of branches. However, there are applications where it is desirable to strictly limit the number of decision points and branches in a plan. This raises the question of how one goes about finding optimal plans containing only a limited number of branches. In this paper, we present an any-time algorithm for optimal k-contingency planning. It is the first optimal algorithm for limited contingency planning that is not an explicit enumeration of possible contingent plans. By modelling the problem as a partially observable Markov decision process, it implements the Bellman optimality principle and prunes the solution space. We present experimental results of applying this algorithm to some simple test cases.

  14. Improved limited discrepancy search

    SciTech Connect

    Korf, R.E.

    1996-12-31

    We present an improvement to Harvey and Ginsberg`s limited discrepancy search algorithm, which eliminates much of the redundancy in the original, by generating each path from the root to the maximum search depth only once. For a complete binary tree of depth d this reduces the asymptotic complexity from O(d+2/2 2{sup d}) to O(2{sup d}). The savings is much less in a partial tree search, or in a heavily pruned tree. The overhead of the improved algorithm on a complete binary tree is only a factor of b/(b - 1) compared to depth-first search. While this constant factor is greater on a heavily pruned tree, this improvement makes limited discrepancy search a viable alternative to depth-first search, whenever the entire tree may not be searched. Finally, we present both positive and negative empirical results on the utility of limited discrepancy search, for the problem of number partitioning.

  15. Force Limit System

    NASA Technical Reports Server (NTRS)

    Pawlik, Ralph; Krause, David; Bremenour, Frank

    2011-01-01

    The Force Limit System (FLS) was developed to protect test specimens from inadvertent overload. The load limit value is fully adjustable by the operator and works independently of the test system control as a mechanical (non-electrical) device. When a test specimen is loaded via an electromechanical or hydraulic test system, a chance of an overload condition exists. An overload applied to a specimen could result in irreparable damage to the specimen and/or fixturing. The FLS restricts the maximum load that an actuator can apply to a test specimen. When testing limited-run test articles or using very expensive fixtures, the use of such a device is highly recommended. Test setups typically use electronic peak protection, which can be the source of overload due to malfunctioning components or the inability to react quickly enough to load spikes. The FLS works independently of the electronic overload protection.

  16. Limitations of angiotensin inhibition.

    PubMed

    Nobakht, Niloofar; Kamgar, Mohammad; Rastogi, Anjay; Schrier, Robert W

    2011-06-01

    Angiotensin-converting-enzyme (ACE) inhibitors and angiotensin-receptor blockers (ARBs) have beneficial effects in patients with cardiovascular disease and in those with diabetes-related and diabetes-independent chronic kidney diseases. These beneficial effects are independent of the antihypertensive properties of these drugs. However, ACE inhibitors, ARBs, and combinations of agents in these two classes are limited in the extent to which they inhibit the activity of the renin-angiotensin-aldosterone system (RAAS). Angiotensin breakthrough and aldosterone breakthrough may be important mechanisms involved in limiting the effects of ACE inhibitors and ARBs. Whether direct renin inhibitors will overcome some of the limitations of ACE-inhibitor and ARB therapy by blocking the deleterious effects of the RAAS remains to be proven. This important area is, however, in need of further investigation.

  17. Cluster functional renormalization group

    NASA Astrophysics Data System (ADS)

    Reuther, Johannes; Thomale, Ronny

    2014-01-01

    Functional renormalization group (FRG) has become a diverse and powerful tool to derive effective low-energy scattering vertices of interacting many-body systems. Starting from a free expansion point of the action, the flow of the RG parameter Λ allows us to trace the evolution of the effective one- and two-particle vertices towards low energies by taking into account the vertex corrections between all parquet channels in an unbiased fashion. In this work, we generalize the expansion point at which the diagrammatic resummation procedure is initiated from a free UV limit to a cluster product state. We formulate a cluster FRG scheme where the noninteracting building blocks (i.e., decoupled spin clusters) are treated exactly, and the intercluster couplings are addressed via RG. As a benchmark study, we apply our cluster FRG scheme to the spin-1/2 bilayer Heisenberg model (BHM) on a square lattice where the neighboring sites in the two layers form the individual two-site clusters. Comparing with existing numerical evidence for the BHM, we obtain reasonable findings for the spin susceptibility, the spin-triplet excitation energy, and quasiparticle weight even in coupling regimes close to antiferromagnetic order. The concept of cluster FRG promises applications to a large class of interacting electron systems.

  18. Estimating turbine limit load

    NASA Technical Reports Server (NTRS)

    Glassman, Arthur J.

    1993-01-01

    A method for estimating turbine limit-load pressure ratio from turbine map information is presented and demonstrated. It is based on a mean line analysis at the last-rotor exit. The required map information includes choke flow rate at all speeds as well as pressure ratio and efficiency at the onset of choke at design speed. One- and two-stage turbines are analyzed to compare the results with those from a more rigorous off-design flow analysis and to show the sensitivities of the computed limit-load pressure ratios to changes in the key assumptions.

  19. Teaching Organizational Behavior Through Discussion Groups

    ERIC Educational Resources Information Center

    Fineman, Stephen; Hamblin, Anthony C.

    1978-01-01

    An educational experiment in teaching organizational behavior to undergraduates in England is reported, with focus on the value and limitations of a systematic form of discussion-group learning based upon a framework outlined by Fawcett Hill. (LBH)

  20. Fundamental Limits to Cellular Sensing

    NASA Astrophysics Data System (ADS)

    ten Wolde, Pieter Rein; Becker, Nils B.; Ouldridge, Thomas E.; Mugler, Andrew

    2016-03-01

    In recent years experiments have demonstrated that living cells can measure low chemical concentrations with high precision, and much progress has been made in understanding what sets the fundamental limit to the precision of chemical sensing. Chemical concentration measurements start with the binding of ligand molecules to receptor proteins, which is an inherently noisy process, especially at low concentrations. The signaling networks that transmit the information on the ligand concentration from the receptors into the cell have to filter this receptor input noise as much as possible. These networks, however, are also intrinsically stochastic in nature, which means that they will also add noise to the transmitted signal. In this review, we will first discuss how the diffusive transport and binding of ligand to the receptor sets the receptor correlation time, which is the timescale over which fluctuations in the state of the receptor, arising from the stochastic receptor-ligand binding, decay. We then describe how downstream signaling pathways integrate these receptor-state fluctuations, and how the number of receptors, the receptor correlation time, and the effective integration time set by the downstream network, together impose a fundamental limit on the precision of sensing. We then discuss how cells can remove the receptor input noise while simultaneously suppressing the intrinsic noise in the signaling network. We describe why this mechanism of time integration requires three classes (groups) of resources—receptors and their integration time, readout molecules, energy—and how each resource class sets a fundamental sensing limit. We also briefly discuss the scheme of maximum-likelihood estimation, the role of receptor cooperativity, and how cellular copy protocols differ from canonical copy protocols typically considered in the computational literature, explaining why cellular sensing systems can never reach the Landauer limit on the optimal trade

  1. Limits to Stability

    ERIC Educational Resources Information Center

    Cottey, Alan

    2012-01-01

    The author reflects briefly on what limited degree of global ecological stability and human cultural stability may be achieved, provided that humanity retains hope and does not give way to despair or hide in denial. These thoughts were triggered by a recent conference on International Stability and Systems Engineering. (Contains 5 notes.)

  2. The Outer Limits: English.

    ERIC Educational Resources Information Center

    Tyler, Barbara R.; Biesekerski, Joan

    The Quinmester course "The Outer Limits" involves an exploration of unknown worlds, mental and physical, through fiction and nonfiction. Its purpose is to focus attention on the ongoing conquest of the frontiers of the mind, the physical world, and outer space. The subject matter includes identification and investigation of unknown worlds in the…

  3. Defined by Limitations

    ERIC Educational Resources Information Center

    Arriola, Sonya; Murphy, Katy

    2010-01-01

    Undocumented students are a population defined by limitations. Their lack of legal residency and any supporting paperwork (e.g., Social Security number, government issued identification) renders them essentially invisible to the American and state governments. They cannot legally work. In many states, they cannot legally drive. After the age of…

  4. Limitations in scatter propagation

    NASA Astrophysics Data System (ADS)

    Lampert, E. W.

    1982-04-01

    A short description of the main scatter propagation mechanisms is presented; troposcatter, meteor burst communication and chaff scatter. For these propagation modes, in particular for troposcatter, the important specific limitations discussed are: link budget and resulting hardware consequences, diversity, mobility, information transfer and intermodulation and intersymbol interference, frequency range and future extension in frequency range for troposcatter, and compatibility with other services (EMC).

  5. Learning without Limits

    ERIC Educational Resources Information Center

    Hart, Susan; Dixon, Annabelle; Drummond, Mary Jane; McIntyre, Donald

    2004-01-01

    This book explores ways of teaching that are free from determinist beliefs about ability. In a detailed critique of the practices of ability labelling and ability-focused teaching, "Learning without Limits" examines the damage these practices can do to young people, teachers and the curriculum. Drawing on a research project at the University of…

  6. Thermal background noise limitations

    NASA Technical Reports Server (NTRS)

    Gulkis, S.

    1982-01-01

    Modern detection systems are increasingly limited in sensitivity by the background thermal photons which enter the receiving system. Expressions for the fluctuations of detected thermal radiation are derived. Incoherent and heterodyne detection processes are considered. References to the subject of photon detection statistics are given.

  7. Intellectually Limited Mothers.

    ERIC Educational Resources Information Center

    Kaminer, Ruth K.; Cohen, Herbert J.

    The paper examines whether a relationship exists between intellectual limitation on the mother's part and unfavorable outcomes for her children. The scope of the problem is examined and the difficulties inherent in estimating prevalence are noted. The issue of child neglect, rather than abuse is shown to be a major problem among institutionalized…

  8. Fracture mechanics validity limits

    NASA Technical Reports Server (NTRS)

    Lambert, Dennis M.; Ernst, Hugo A.

    1994-01-01

    Fracture behavior is characteristics of a dramatic loss of strength compared to elastic deformation behavior. Fracture parameters have been developed and exhibit a range within which each is valid for predicting growth. Each is limited by the assumptions made in its development: all are defined within a specific context. For example, the stress intensity parameters, K, and the crack driving force, G, are derived using an assumption of linear elasticity. To use K or G, the zone of plasticity must be small as compared to the physical dimensions of the object being loaded. This insures an elastic response, and in this context, K and G will work well. Rice's J-integral has been used beyond the limits imposed on K and G. J requires an assumption of nonlinear elasticity, which is not characteristic of real material behavior, but is thought to be a reasonable approximation if unloading is kept to a minimum. As well, the constraint cannot change dramatically (typically, the crack extension is limited to ten-percent of the initial remaining ligament length). Rice, et al investigated the properties required of J-type parameters, J(sub x), and showed that the time rate, dJ(sub x)/dt, must not be a function of the crack extension rate, da/dt. Ernst devised the modified-J parameter, J(sub M), that meets this criterion. J(sub M) correlates fracture data to much higher crack growth than does J. Ultimately, a limit of the validity of J(sub M) is anticipated, and this has been estimated to be at a crack extension of about 40-percent of the initial remaining ligament length. None of the various parameters can be expected to describe fracture in an environment of gross plasticity, in which case the process is better described by deformation parameters, e.g., stress and strain. In the current study, various schemes to identify the onset of the plasticity-dominated behavior, i.e., the end of fracture mechanics validity, are presented. Each validity limit parameter is developed in

  9. Telescopic limiting magnitudes

    NASA Technical Reports Server (NTRS)

    Schaefer, Bradley E.

    1990-01-01

    The prediction of the magnitude of the faintest star visible through a telescope by a visual observer is a difficult problem in physiology. Many prediction formulas have been advanced over the years, but most do not even consider the magnification used. Here, the prediction algorithm problem is attacked with two complimentary approaches: (1) First, a theoretical algorithm was developed based on physiological data for the sensitivity of the eye. This algorithm also accounts for the transmission of the atmosphere and the telescope, the brightness of the sky, the color of the star, the age of the observer, the aperture, and the magnification. (2) Second, 314 observed values for the limiting magnitude were collected as a test of the formula. It is found that the formula does accurately predict the average observed limiting magnitudes under all conditions.

  10. Quantum limits of thermometry

    SciTech Connect

    Stace, Thomas M.

    2010-07-15

    The precision of typical thermometers consisting of N particles scales as {approx}1/{radical}(N). For high-precision thermometry and thermometric standards, this presents an important theoretical noise floor. Here it is demonstrated that thermometry may be mapped onto the problem of phase estimation, and using techniques from optimal phase estimation, it follows that the scaling of the precision of a thermometer may in principle be improved to {approx}1/N, representing a Heisenberg limit to thermometry.

  11. Heat flux limiting sleeves

    DOEpatents

    Harris, William G.

    1985-01-01

    A heat limiting tubular sleeve extending over only a portion of a tube having a generally uniform outside diameter, the sleeve being open on both ends, having one end thereof larger in diameter than the other end thereof and having a wall thickness which decreases in the same direction as the diameter of the sleeve decreases so that the heat transfer through the sleeve and tube is less adjacent the large diameter end of the sleeve than adjacent the other end thereof.

  12. Limits of proton conductivity.

    PubMed

    Kreuer, Klaus-Dieter; Wohlfarth, Andreas

    2012-10-15

    Parasitic current seems to be the cause for the "highest proton conductivity" of a material reported to date. Kreuer and Wohlfarth verify this hypothesis by measuring the conductivity of the same materials after preparing them in a different way. They further explain the limits of proton conductivity and comment on the problems of determining the conductivity of small objects (e.g., whiskers, see picture).

  13. Participants' Perception of Therapeutic Factors in Groups for Incest Survivors.

    ERIC Educational Resources Information Center

    Wheeler, Inese; And Others

    1992-01-01

    Investigated member-perceived curative factors in an incest-survivor group, comparing therapeutic factors reported in closed, time-limited incest survivor group to those in Bonney et al.'s open, long-term survivor group and to Yalom's therapy groups. Findings suggest that relative importance of curative factors may be related to group stages.…

  14. Limits of social mobilization.

    PubMed

    Rutherford, Alex; Cebrian, Manuel; Dsouza, Sohan; Moro, Esteban; Pentland, Alex; Rahwan, Iyad

    2013-04-16

    The Internet and social media have enabled the mobilization of large crowds to achieve time-critical feats, ranging from mapping crises in real time, to organizing mass rallies, to conducting search-and-rescue operations over large geographies. Despite significant success, selection bias may lead to inflated expectations of the efficacy of social mobilization for these tasks. What are the limits of social mobilization, and how reliable is it in operating at these limits? We build on recent results on the spatiotemporal structure of social and information networks to elucidate the constraints they pose on social mobilization. We use the DARPA Network Challenge as our working scenario, in which social media were used to locate 10 balloons across the United States. We conduct high-resolution simulations for referral-based crowdsourcing and obtain a statistical characterization of the population recruited, geography covered, and time to completion. Our results demonstrate that the outcome is plausible without the presence of mass media but lies at the limit of what time-critical social mobilization can achieve. Success relies critically on highly connected individuals willing to mobilize people in distant locations, overcoming the local trapping of diffusion in highly dense areas. However, even under these highly favorable conditions, the risk of unsuccessful search remains significant. These findings have implications for the design of better incentive schemes for social mobilization. They also call for caution in estimating the reliability of this capability. PMID:23576719

  15. Limits of social mobilization.

    PubMed

    Rutherford, Alex; Cebrian, Manuel; Dsouza, Sohan; Moro, Esteban; Pentland, Alex; Rahwan, Iyad

    2013-04-16

    The Internet and social media have enabled the mobilization of large crowds to achieve time-critical feats, ranging from mapping crises in real time, to organizing mass rallies, to conducting search-and-rescue operations over large geographies. Despite significant success, selection bias may lead to inflated expectations of the efficacy of social mobilization for these tasks. What are the limits of social mobilization, and how reliable is it in operating at these limits? We build on recent results on the spatiotemporal structure of social and information networks to elucidate the constraints they pose on social mobilization. We use the DARPA Network Challenge as our working scenario, in which social media were used to locate 10 balloons across the United States. We conduct high-resolution simulations for referral-based crowdsourcing and obtain a statistical characterization of the population recruited, geography covered, and time to completion. Our results demonstrate that the outcome is plausible without the presence of mass media but lies at the limit of what time-critical social mobilization can achieve. Success relies critically on highly connected individuals willing to mobilize people in distant locations, overcoming the local trapping of diffusion in highly dense areas. However, even under these highly favorable conditions, the risk of unsuccessful search remains significant. These findings have implications for the design of better incentive schemes for social mobilization. They also call for caution in estimating the reliability of this capability.

  16. Elastic limit of silicane.

    PubMed

    Peng, Qing; De, Suvranu

    2014-10-21

    Silicane is a fully hydrogenated silicene-a counterpart of graphene-having promising applications in hydrogen storage with capacities larger than 6 wt%. Knowledge of its elastic limit is critical in its applications as well as tailoring its electronic properties by strain. Here we investigate the mechanical response of silicane to various strains using first-principles calculations based on density functional theory. We illustrate that non-linear elastic behavior is prominent in two-dimensional nanomaterials as opposed to bulk materials. The elastic limits defined by ultimate tensile strains are 0.22, 0.28, and 0.25 along armchair, zigzag, and biaxial directions, respectively, an increase of 29%, 33%, and 24% respectively in reference to silicene. The in-plane stiffness and Poisson ratio are reduced by a factor of 16% and 26%, respectively. However, hydrogenation/dehydrogenation has little effect on its ultimate tensile strengths. We obtained high order elastic constants for a rigorous continuum description of the nonlinear elastic response. The limitation of second, third, fourth, and fifth order elastic constants are in the strain range of 0.02, 0.08, and 0.13, and 0.21, respectively. The pressure effect on the second order elastic constants and Poisson's ratio were predicted from the third order elastic constants. Our results could provide a safe guide for promising applications and strain-engineering the functions and properties of silicane monolayers. PMID:25190587

  17. LIMITS ON QUAOAR'S ATMOSPHERE

    SciTech Connect

    Fraser, Wesley C.; Gwyn, Stephen; Kavelaars, J. J.; Trujillo, Chad; Stephens, Andrew W.; Gimeno, German

    2013-09-10

    Here we present high cadence photometry taken by the Acquisition Camera on Gemini South, of a close passage by the {approx}540 km radius Kuiper belt object, (50000) Quaoar, of a r' = 20.2 background star. Observations before and after the event show that the apparent impact parameter of the event was 0.''019 {+-} 0.''004, corresponding to a close approach of 580 {+-} 120 km to the center of Quaoar. No signatures of occultation by either Quaoar's limb or its potential atmosphere are detectable in the relative photometry of Quaoar and the target star, which were unresolved during closest approach. From this photometry we are able to put constraints on any potential atmosphere Quaoar might have. Using a Markov chain Monte Carlo and likelihood approach, we place pressure upper limits on sublimation supported, isothermal atmospheres of pure N{sub 2}, CO, and CH{sub 4}. For N{sub 2} and CO, the upper limit surface pressures are 1 and 0.7 {mu}bar, respectively. The surface temperature required for such low sublimation pressures is {approx}33 K, much lower than Quaoar's mean temperature of {approx}44 K measured by others. We conclude that Quaoar cannot have an isothermal N{sub 2} or CO atmosphere. We cannot eliminate the possibility of a CH{sub 4} atmosphere, but place upper surface pressure and mean temperature limits of {approx}138 nbar and {approx}44 K, respectively.

  18. Limits of social mobilization

    PubMed Central

    Rutherford, Alex; Cebrian, Manuel; Dsouza, Sohan; Moro, Esteban; Pentland, Alex; Rahwan, Iyad

    2013-01-01

    The Internet and social media have enabled the mobilization of large crowds to achieve time-critical feats, ranging from mapping crises in real time, to organizing mass rallies, to conducting search-and-rescue operations over large geographies. Despite significant success, selection bias may lead to inflated expectations of the efficacy of social mobilization for these tasks. What are the limits of social mobilization, and how reliable is it in operating at these limits? We build on recent results on the spatiotemporal structure of social and information networks to elucidate the constraints they pose on social mobilization. We use the DARPA Network Challenge as our working scenario, in which social media were used to locate 10 balloons across the United States. We conduct high-resolution simulations for referral-based crowdsourcing and obtain a statistical characterization of the population recruited, geography covered, and time to completion. Our results demonstrate that the outcome is plausible without the presence of mass media but lies at the limit of what time-critical social mobilization can achieve. Success relies critically on highly connected individuals willing to mobilize people in distant locations, overcoming the local trapping of diffusion in highly dense areas. However, even under these highly favorable conditions, the risk of unsuccessful search remains significant. These findings have implications for the design of better incentive schemes for social mobilization. They also call for caution in estimating the reliability of this capability. PMID:23576719

  19. Deriving exposure limits

    NASA Astrophysics Data System (ADS)

    Sliney, David H.

    1990-07-01

    Historically many different agencies and standards organizations have proposed laser occupational exposure limits (EL1s) or maximum permissible exposure (MPE) levels. Although some safety standards have been limited in scope to manufacturer system safety performance standards or to codes of practice most have included occupational EL''s. Initially in the 1960''s attention was drawn to setting EL''s however as greater experience accumulated in the use of lasers and some accident experience had been gained safety procedures were developed. It became clear by 1971 after the first decade of laser use that detailed hazard evaluation of each laser environment was too complex for most users and a scheme of hazard classification evolved. Today most countries follow a scheme of four major hazard classifications as defined in Document WS 825 of the International Electrotechnical Commission (IEC). The classifications and the associated accessible emission limits (AEL''s) were based upon the EL''s. The EL and AEL values today are in surprisingly good agreement worldwide. There exists a greater range of safety requirements for the user for each class of laser. The current MPE''s (i. e. EL''s) and their basis are highlighted in this presentation. 2. 0

  20. USENET Discussion Groups in Political Science Courses.

    ERIC Educational Resources Information Center

    Bailey, Martha

    1995-01-01

    Considers the applications and limitations of supplementing political science instruction with USENET discussion groups. Maintains that the engaging and topical nature of the discussion groups can enhance traditional course materials. Notes, however, that USENET comments often are not indicative of the general public. Briefly discusses reference…

  1. Leading Deep Conversations in Collaborative Inquiry Groups

    ERIC Educational Resources Information Center

    Nelson, Tamara Holmlund; Deuel, Angie; Slavit, David; Kennedy, Anne

    2010-01-01

    Collaborative inquiry groups, such as professional learning communities and lesson study groups, are proliferating in schools across the United States. In whatever form, the potential for impacting student learning through this collaborative work is expanded or limited by the nature of teachers' conversations. Polite, congenial conversations…

  2. Focus Groups with Linguistically Marginalized Populations.

    ERIC Educational Resources Information Center

    Pardi, Marco M.

    The focus group method has rapidly gained credibility among researchers in many fields, including public health researchers. The increased use of focus groups by public health researchers has underscored the demonstrable need for the capacity to apply this method of research among populations with limited abilities in or cultural resistance to…

  3. Properties of satellite galaxies in nearby groups

    NASA Astrophysics Data System (ADS)

    Vennik, Jaan

    2016-10-01

    We studied the variation of stellar mass and various star-formation characteristics of satellite galaxies in a volume limited sample of nearby groups as a function of their group-centric distance and of their relative line-of-sight velocity in the group rest frame. We found clear radial dependencies, e.g. massive, red and passive satellites being distributed predominantly near the center of composite group. We also found some evidence of velocity modulation of star-forming properties of satellite galaxies near the group virial radius. We conclude that using kinematical data, it should be feasible to separate dynamical classes of bound, in-falling and 'backsplash' satellite galaxies.

  4. Limit cycles and conformal invariance

    NASA Astrophysics Data System (ADS)

    Fortin, Jean-François; Grinstein, Benjamín; Stergiou, Andreas

    2013-01-01

    There is a widely held belief that conformal field theories (CFTs) require zero beta functions. Nevertheless, the work of Jack and Osborn implies that the beta functions are not actually the quantites that decide conformality, but until recently no such behavior had been exhibited. Our recent work has led to the discovery of CFTs with nonzero beta functions, more precisely CFTs that live on recurrent trajectories, e.g., limit cycles, of the beta-function vector field. To demonstrate this we study the S function of Jack and Osborn. We use Weyl consistency conditions to show that it vanishes at fixed points and agrees with the generator Q of limit cycles on them. Moreover, we compute S to third order in perturbation theory, and explicitly verify that it agrees with our previous determinations of Q. A byproduct of our analysis is that, in perturbation theory, unitarity and scale invariance imply conformal invariance in four-dimensional quantum field theories. Finally, we study some properties of these new, "cyclic" CFTs, and point out that the a-theorem still governs the asymptotic behavior of renormalization-group flows.

  5. The GROOP Effect: Groups Mimic Group Actions

    ERIC Educational Resources Information Center

    Tsai, Jessica Chia-Chin; Sebanz, Natalie; Knoblich, Gunther

    2011-01-01

    Research on perception-action links has focused on an interpersonal level, demonstrating effects of observing individual actions on performance. The present study investigated perception-action matching at an inter-group level. Pairs of participants responded to hand movements that were performed by two individuals who used one hand each or they…

  6. The limits of scale.

    PubMed

    Halaburda, Hanna; Oberholzer-Gee, Felix

    2014-04-01

    The value of many products and services rises or falls with the number of customers using them; the fewer fax machines in use, the less important it is to have one. These network effects influence consumer decisions and affect companies' ability to compete. Strategists have developed some well-known rules for navigating business environments with network effects. "Move first" is one, and "get big fast" is another. In a study of dozens of companies, however, the authors found that quite often the conventional wisdom was dead wrong. And when the rules failed, the reason was always the same: Companies trip up when they try to attract large volumes of customers without understanding (1) the strength of mutual attraction among various customer groups and (2) the extent of asymmetric attraction among them. Looking at examples such as TripAdvisor, Wikipedia, and the New York Times, the authors offer strategies for competing in markets with network effects. New entrants should focus on customer groups that they are uniquely positioned to serve or appeal to the most attractive customers in a market. Incumbents pursuing growth strategies in adjacent markets or new geographies should consider how similar the needs of new customers are to those of existing customers. Offering complements also allows incumbents to reach additional customer groups. PMID:24830285

  7. Fault current limiter

    DOEpatents

    Darmann, Francis Anthony

    2013-10-08

    A fault current limiter (FCL) includes a series of high permeability posts for collectively define a core for the FCL. A DC coil, for the purposes of saturating a portion of the high permeability posts, surrounds the complete structure outside of an enclosure in the form of a vessel. The vessel contains a dielectric insulation medium. AC coils, for transporting AC current, are wound on insulating formers and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil in the corresponding high permeability core are opposing. There are insulation barriers between phases to improve dielectric withstand properties of the dielectric medium.

  8. What Makes Groups Tick.

    ERIC Educational Resources Information Center

    Allcorn, Seth

    1985-01-01

    By reviewing this analysis of the behavior of both groups and individuals in groups, human resources managers can learn to tell whether committees, task forces, and departments may be encouraging or inhibiting the work they set out to do. (Author)

  9. Nilpotent -local finite groups

    NASA Astrophysics Data System (ADS)

    Cantarero, José; Scherer, Jérôme; Viruel, Antonio

    2014-10-01

    We provide characterizations of -nilpotency for fusion systems and -local finite groups that are inspired by known result for finite groups. In particular, we generalize criteria by Atiyah, Brunetti, Frobenius, Quillen, Stammbach and Tate.

  10. 14 CFR 161.7 - Limitations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... subject to this part. Other noise abatement procedures, such as taxiing and engine runups, are not subject... working group (outside of the process established by 14 CFR part 150) with a local airport operator to... NOTICE AND APPROVAL OF AIRPORT NOISE AND ACCESS RESTRICTIONS General Provisions § 161.7 Limitations....

  11. Internet minimal group paradigm.

    PubMed

    Amichai-Hamburger, Yair

    2005-04-01

    Over many years, social psychologists have sought to understand what causes individuals to form themselves into groups. Initially, it was believed that groups were formed when people bonded around a common goal. Later, it was found that, when individuals were divided into groups on a random basis, this in itself was sufficient for them to feel part of a group and show a preference for their own group over others. Since the environment in cyberspace is different from that of the offline world, for example, there is no physical proximity between participants; it may be assumed that it would be difficult to achieve feelings of affiliation among potential or actual group members. This pioneer study seeks to discover which components are requisite to the creation of a group identity among individuals surfing the Internet. For this experiment, 24 people were divided into two Internet chat groups according to their intuitive preference in a decision-making task. It was found that group members perceived their own group performance as superior on a cognitive task as compared with that of the other group. These results demonstrate that for surfers, the Internet experience is very real and even a trivial allocation of people to a group is likely to create a situation of ingroup favoritism. PMID:15938653

  12. Practice and Group Learning

    ERIC Educational Resources Information Center

    Hager, Paul

    2014-01-01

    Although learning has always been a central topic for philosophy of education, little attention has been paid to the notion of group learning. This article outlines and discusses some plausible examples of group learning. Drawing on these examples, various principles and issues that surround the notion of group learning are identified and…

  13. Infant Group Care Risks.

    ERIC Educational Resources Information Center

    Kendall, Earline D.

    Children under 3 years of age who are in group care face special health risks. The U.S. Centers for Disease Control indicate the existence of a causal relationship between infant group day care and certain diseases that are spread through contact at day care centers. Children in group care who are still in diapers are especially vulnerable to…

  14. Internet Discussion Groups.

    ERIC Educational Resources Information Center

    Bull, Glen; Bull, Gina; Sigmon, Tim

    1997-01-01

    Discusses newsgroups, listservs, and Web-based discussion groups. Highlights include major categories of international USENET discussion groups; newsgroups versus mailing lists; newsreaders; news servers; newsgroup subscriptions; newsgroups versus Web discussion groups; linking newsgroups, mailing lists, and the Web; and setting up a news host. A…

  15. Integrated Play Groups

    ERIC Educational Resources Information Center

    Glovak, Sandra

    2007-01-01

    As an occupational therapist running social play groups with sensory integration for children on the autism spectrum, the author frequently doubted the wisdom of combining several children on the spectrum into a group. In fact, as the owner of a clinic she said, "No more!" The groups seemed like a waste of parents' time and money, and she refused…

  16. Working Group 7 Summary

    SciTech Connect

    Nagaitsev S.; Berg J.

    2012-06-10

    The primary subject of working group 7 at the 2012 Advanced Accelerator Concepts Workshop was muon accelerators for a muon collider or neutrino factory. Additionally, this working group included topics that did not fit well into other working groups. Two subjects were discussed by more than one speaker: lattices to create a perfectly integrable nonlinear lattice, and a Penning trap to create antihydrogen.

  17. Parent Group Spotlight

    ERIC Educational Resources Information Center

    Parenting for High Potential, 2014

    2014-01-01

    This issue's "Parent Group Spotlight" features Deborah Simon, president of West Sound Gifted, Talented & Twice-Exceptional (WSGT2e), who started a parent group in Washington in 2013. In just one year, this small, but mighty group has held community forums, attended school board meetings, and helped influence local gifted programming.…

  18. Limitations of inclusive fitness.

    PubMed

    Allen, Benjamin; Nowak, Martin A; Wilson, Edward O

    2013-12-10

    Until recently, inclusive fitness has been widely accepted as a general method to explain the evolution of social behavior. Affirming and expanding earlier criticism, we demonstrate that inclusive fitness is instead a limited concept, which exists only for a small subset of evolutionary processes. Inclusive fitness assumes that personal fitness is the sum of additive components caused by individual actions. This assumption does not hold for the majority of evolutionary processes or scenarios. To sidestep this limitation, inclusive fitness theorists have proposed a method using linear regression. On the basis of this method, it is claimed that inclusive fitness theory (i) predicts the direction of allele frequency changes, (ii) reveals the reasons for these changes, (iii) is as general as natural selection, and (iv) provides a universal design principle for evolution. In this paper we evaluate these claims, and show that all of them are unfounded. If the objective is to analyze whether mutations that modify social behavior are favored or opposed by natural selection, then no aspect of inclusive fitness theory is needed.

  19. Limitations of inclusive fitness

    PubMed Central

    Allen, Benjamin; Nowak, Martin A.; Wilson, Edward O.

    2013-01-01

    Until recently, inclusive fitness has been widely accepted as a general method to explain the evolution of social behavior. Affirming and expanding earlier criticism, we demonstrate that inclusive fitness is instead a limited concept, which exists only for a small subset of evolutionary processes. Inclusive fitness assumes that personal fitness is the sum of additive components caused by individual actions. This assumption does not hold for the majority of evolutionary processes or scenarios. To sidestep this limitation, inclusive fitness theorists have proposed a method using linear regression. On the basis of this method, it is claimed that inclusive fitness theory (i) predicts the direction of allele frequency changes, (ii) reveals the reasons for these changes, (iii) is as general as natural selection, and (iv) provides a universal design principle for evolution. In this paper we evaluate these claims, and show that all of them are unfounded. If the objective is to analyze whether mutations that modify social behavior are favored or opposed by natural selection, then no aspect of inclusive fitness theory is needed. PMID:24277847

  20. Limits to biofuels

    NASA Astrophysics Data System (ADS)

    Johansson, S.

    2013-06-01

    Biofuel production is dependent upon agriculture and forestry systems, and the expectations of future biofuel potential are high. A study of the global food production and biofuel production from edible crops implies that biofuel produced from edible parts of crops lead to a global deficit of food. This is rather well known, which is why there is a strong urge to develop biofuel systems that make use of residues or products from forest to eliminate competition with food production. However, biofuel from agro-residues still depend upon the crop production system, and there are many parameters to deal with in order to investigate the sustainability of biofuel production. There is a theoretical limit to how much biofuel can be achieved globally from agro-residues and this amounts to approximately one third of todays' use of fossil fuels in the transport sector. In reality this theoretical potential may be eliminated by the energy use in the biomass-conversion technologies and production systems, depending on what type of assessment method is used. By surveying existing studies on biofuel conversion the theoretical limit of biofuels from 2010 years' agricultural production was found to be either non-existent due to energy consumption in the conversion process, or up to 2-6000TWh (biogas from residues and waste and ethanol from woody biomass) in the more optimistic cases.

  1. ITER global stability limits

    SciTech Connect

    Hogan, J.T.; Uckan, N.A.

    1990-01-01

    The MHD stability limits to the ITER operational space have been examined with the PEST ideal stability code. Constraints on ITER operation have been examined for the nominal operational scenarios and for possible design variants. Rather than rely on evaluation of a relatively small number of sample cases, the approach has been to construct an approximation to the overall operational space, and to compare this with the observed limits in high-{beta} tokamaks. An extensive database with {approximately}20,000 stability results has been compiled for use by the ITER design team. Results from these studies show that the design values of the Troyon factor (g {approximately} 2.5 for ignition studies, and g {approximately} 3 for the technology phase) which are based on present experiments, are also expected to be attainable for ITER conditions, for which the configuration and wall-stabilisation environment differ from those in present experiments. Strongly peaked pressure profiles lead to degraded high-{beta} performance. Values of g {approximately} 4 are found for higher safety factor (q {sub {Psi}} {le} 4) than that of the present design (q{sub {Psi}} {approximately} 3). Profiles with q(0) < 1 are shown to give g {approximately} 2.5, if the current density profile provides optimum shear. The overall operational spaces are presented for g-q{sub {Psi}}, q{sub {Psi}}-1{sub i}, q-{alpha}{sub p} and l{sub i}-q{sub {psi}}.

  2. Grouped exposed metal heaters

    SciTech Connect

    Vinegar, Harold J.; Coit, William George; Griffin, Peter Terry; Hamilton, Paul Taylor; Hsu, Chia-Fu; Mason, Stanley Leroy; Samuel, Allan James; Watkins, Ronnie Wade

    2012-07-31

    A system for treating a hydrocarbon containing formation is described. The system includes two or more groups of elongated heaters. The group includes two or more heaters placed in two or more openings in the formation. The heaters in the group are electrically coupled below the surface of the formation. The openings include at least partially uncased wellbores in a hydrocarbon layer of the formation. The groups are electrically configured such that current flow through the formation between at least two groups is inhibited. The heaters are configured to provide heat to the formation.

  3. Grouped exposed metal heaters

    DOEpatents

    Vinegar, Harold J.; Coit, William George; Griffin, Peter Terry; Hamilton, Paul Taylor; Hsu, Chia-Fu; Mason, Stanley Leroy; Samuel, Allan James; Watkins, Ronnie Wade

    2010-11-09

    A system for treating a hydrocarbon containing formation is described. The system includes two or more groups of elongated heaters. The group includes two or more heaters placed in two or more openings in the formation. The heaters in the group are electrically coupled below the surface of the formation. The openings include at least partially uncased wellbores in a hydrocarbon layer of the formation. The groups are electrically configured such that current flow through the formation between at least two groups is inhibited. The heaters are configured to provide heat to the formation.

  4. Work group diversity.

    PubMed

    van Knippenberg, Daan; Schippers, Michaéla C

    2007-01-01

    Work group diversity, the degree to which there are differences between group members, may affect group process and performance positively as well as negatively. Much is still unclear about the effects of diversity, however. We review the 1997-2005 literature on work group diversity to assess the state of the art and to identify key issues for future research. This review points to the need for more complex conceptualizations of diversity, as well as to the need for more empirical attention to the processes that are assumed to underlie the effects of diversity on group process and performance and to the contingency factors of these processes.

  5. Work group diversity.

    PubMed

    van Knippenberg, Daan; Schippers, Michaéla C

    2007-01-01

    Work group diversity, the degree to which there are differences between group members, may affect group process and performance positively as well as negatively. Much is still unclear about the effects of diversity, however. We review the 1997-2005 literature on work group diversity to assess the state of the art and to identify key issues for future research. This review points to the need for more complex conceptualizations of diversity, as well as to the need for more empirical attention to the processes that are assumed to underlie the effects of diversity on group process and performance and to the contingency factors of these processes. PMID:16903805

  6. Physical limits to magnetogenetics.

    PubMed

    Meister, Markus

    2016-01-01

    This is an analysis of how magnetic fields affect biological molecules and cells. It was prompted by a series of prominent reports regarding magnetism in biological systems. The first claims to have identified a protein complex that acts like a compass needle to guide magnetic orientation in animals (Qin et al., 2016). Two other articles report magnetic control of membrane conductance by attaching ferritin to an ion channel protein and then tugging the ferritin or heating it with a magnetic field (Stanley et al., 2015; Wheeler et al., 2016). Here I argue that these claims conflict with basic laws of physics. The discrepancies are large: from 5 to 10 log units. If the reported phenomena do in fact occur, they must have causes entirely different from the ones proposed by the authors. The paramagnetic nature of protein complexes is found to seriously limit their utility for engineering magnetically sensitive cells. PMID:27529126

  7. Nature limits filarial transmission

    PubMed Central

    Chandra, Goutam

    2008-01-01

    Lymphatic filariasis, caused by Wuchereria bancrofti, Brugia malayi and B. timori is a public health problem of considerable magnitude of the tropics and subtropics. Presently 1.3 billion people are at risk of lymphatic filariasis (LF) infection and about 120 million people are affected in 83 countries. In this context it is worth mentioning that 'nature' itself limits filarial transmission to a great extent in a number of ways such as by reducing vector populations, parasitic load and many other bearings. Possibilities to utilize these bearings of natural control of filariasis should be searched and if manipulations on nature, like indiscriminate urbanization and deforestation, creating sites favourable for the breeding of filarial vectors and unsanitary conditions, water pollution with organic matters etc., are reduced below the threshold level, we will be highly benefited. Understandings of the factors related to natural phenomena of control of filariasis narrated in this article may help to adopt effective control strategies. PMID:18500974

  8. Clinical limitations of Invisalign.

    PubMed

    Phan, Xiem; Ling, Paul H

    2007-04-01

    Adult patients seeking orthodontic treatment are increasingly motivated by esthetic considerations. The majority of these patients reject wearing labial fixed appliances and are looking instead to more esthetic treatment options, including lingual orthodontics and Invisalign appliances. Since Align Technology introduced the Invisalign appliance in 1999 in an extensive public campaign, the appliance has gained tremendous attention from adult patients and dental professionals. The transparency of the Invisalign appliance enhances its esthetic appeal for those adult patients who are averse to wearing conventional labial fixed orthodontic appliances. Although guidelines about the types of malocclusions that this technique can treat exist, few clinical studies have assessed the effectiveness of the appliance. A few recent studies have outlined some of the limitations associated with this technique that clinicians should recognize early before choosing treatment options.

  9. The Limits to Relevance

    NASA Astrophysics Data System (ADS)

    Averill, M.; Briggle, A.

    2006-12-01

    Science policy and knowledge production lately have taken a pragmatic turn. Funding agencies increasingly are requiring scientists to explain the relevance of their work to society. This stems in part from mounting critiques of the "linear model" of knowledge production in which scientists operating according to their own interests or disciplinary standards are presumed to automatically produce knowledge that is of relevance outside of their narrow communities. Many contend that funded scientific research should be linked more directly to societal goals, which implies a shift in the kind of research that will be funded. While both authors support the concept of useful science, we question the exact meaning of "relevance" and the wisdom of allowing it to control research agendas. We hope to contribute to the conversation by thinking more critically about the meaning and limits of the term "relevance" and the trade-offs implicit in a narrow utilitarian approach. The paper will consider which interests tend to be privileged by an emphasis on relevance and address issues such as whose goals ought to be pursued and why, and who gets to decide. We will consider how relevance, narrowly construed, may actually limit the ultimate utility of scientific research. The paper also will reflect on the worthiness of research goals themselves and their relationship to a broader view of what it means to be human and to live in society. Just as there is more to being human than the pragmatic demands of daily life, there is more at issue with knowledge production than finding the most efficient ways to satisfy consumer preferences or fix near-term policy problems. We will conclude by calling for a balanced approach to funding research that addresses society's most pressing needs but also supports innovative research with less immediately apparent application.

  10. Instrumentation Working Group Summary

    NASA Technical Reports Server (NTRS)

    Zaller, Michelle; Miake-Lye, Richard

    1999-01-01

    The Instrumentation Working Group compiled a summary of measurement techniques applicable to gas turbine engine aerosol precursors and particulates. An assessment was made of the limits, accuracy, applicability, and technology readiness of the various techniques. Despite advances made in emissions characterization of aircraft engines, uncertainties still exist in the mechanisms by which aerosols and particulates are produced in the near-field engine exhaust. To adequately assess current understanding of the formation of sulfuric acid aerosols in the exhaust plumes of gas turbine engines, measurements are required to determine the degree and importance of sulfur oxidation in the turbine and at the engine exit. Ideally, concentrations of all sulfur species would be acquired, with emphasis on SO2 and SO3. Numerous options exist for extractive and non-extractive measurement of SO2 at the engine exit, most of which are well developed. SO2 measurements should be performed first to place an upper bound on the percentage of SO2 oxidation. If extractive and non-extractive techniques indicate that a large amount of the fuel sulfur is not detected as SO2, then efforts are needed to improve techniques for SO3 measurements. Additional work will be required to account for the fuel sulfur in the engine exhaust. Chemical Ionization Mass Spectrometry (CI-MS) measurements need to be pursued, although a careful assessment needs to be made of the sampling line impact on the extracted sample composition. Efforts should also be placed on implementing non-intrusive techniques and extending their capabilities by maximizing exhaust coverage for line-of-sight measurements, as well as development of 2-D techniques, where feasible. Recommendations were made to continue engine exit and combustor measurements of particulates. Particulate measurements should include particle size distribution, mass fraction, hydration properties, and volatile fraction. However, methods to ensure that unaltered

  11. Group Psychotherapy in Italy.

    PubMed

    Giannone, Francesca; Giordano, Cecilia; Di Blasi, Maria

    2015-10-01

    This article describes the history and the prevailing orientations of group psychotherapy in Italy (psychoanalytically oriented, psychodrama, CBT groups) and particularly group analysis. Provided free of charge by the Italian health system, group psychotherapy is growing, but its expansion is patchy. The main pathways of Italian training in the different group psychotherapy orientations are also presented. Clinical-theoretical elaboration on self development, psychopathology related to group experiences, and the methodological attention paid to objectives and methods in different clinical groups are issues related to group therapy in Italy. Difficulties in the relationship between research and clinical practice are discussed, as well as the empirical research network that tries to bridge the gap between research and clinical work in group psychotherapy. The economic crisis in Italy has led to massive cuts in health care and to an increasing demand for some forms of psychological treatment. For these reasons, and because of its positive cost-benefit ratio, group psychotherapy is now considered an important tool in the national health care system to expand the clinical response to different forms of psychological distress. PMID:26401793

  12. Blood groups systems

    PubMed Central

    Mitra, Ranadhir; Mishra, Nitasha; Rath, Girija Prasad

    2014-01-01

    International Society of Blood Transfusion has recently recognized 33 blood group systems. Apart from ABO and Rhesus system, many other types of antigens have been noticed on the red cell membranes. Blood grouping and cross-matching is one of the few important tests that the anaesthesiologist orders during perioperative period. Hence, a proper understanding of the blood group system, their clinical significance, typing and cross-matching tests, and current perspective are of paramount importance to prevent transfusion-related complications. Nonetheless, the knowledge on blood group system is necessary to approach blood group-linked diseases which are still at the stage of research. This review addresses all these aspects of the blood groups system. PMID:25535412

  13. Blood groups systems.

    PubMed

    Mitra, Ranadhir; Mishra, Nitasha; Rath, Girija Prasad

    2014-09-01

    International Society of Blood Transfusion has recently recognized 33 blood group systems. Apart from ABO and Rhesus system, many other types of antigens have been noticed on the red cell membranes. Blood grouping and cross-matching is one of the few important tests that the anaesthesiologist orders during perioperative period. Hence, a proper understanding of the blood group system, their clinical significance, typing and cross-matching tests, and current perspective are of paramount importance to prevent transfusion-related complications. Nonetheless, the knowledge on blood group system is necessary to approach blood group-linked diseases which are still at the stage of research. This review addresses all these aspects of the blood groups system. PMID:25535412

  14. Brucellosis in Occupationally Exposed Groups

    PubMed Central

    Sajjan, Annapurna G.; Mohite, Shivajirao T.; Gajul, Shivali

    2016-01-01

    Introduction In India, high incidence of human brucellosis may be expected, as the conditions conducive for human brucellosis exist. Limited studies have been undertaken on human brucellosis especially in occupationally-exposed groups. Aim To estimate prevalence of anti-brucellar antibodies, evaluate the clinical manifestations, risk factors and Knowledge, Attitude and Practices (KAP) levels about brucellosis among occupationally exposed groups. Materials and Methods Blood samples were collected from 2337 occupationally exposed individuals. The serum samples were screened for the presence of anti-brucellar antibodies by Rose Bengal Plate Test (RBPT), Serum Agglutination Test (SAT) and 2-Mercaptoethanol test (2-ME). Clinical manifestations, risk factors and KAP levels were evaluated by personal interview using a structured questionnaire. Results Seroprevalence of brucellosis by RBPT, SAT and 2-ME test was 9.46%, 4.45% and 3.64 % respectively. Clinical symptoms resembling brucellosis were seen in 91 subjects. The major risk factors were animal exposure in veterinarians and abattoirs, both animal exposure and raw milk ingestion in farmers and shepherds, exposure to raw milk and its ingestion in dairy workers and exposure to Brucella culture in laboratory workers. Except laboratory workers, few veterinarians and dairy workers none had heard about brucellosis. KAP levels regarding brucellosis were too poor in all the groups except laboratory workers. Conclusion Brucellosis most of the times was missed or misdiagnosed. Regular screenings for brucellosis and awareness programmes to increase KAP levels are necessary to control brucellosis in occupationally exposed groups. PMID:27190804

  15. E-Group Arrangements

    NASA Astrophysics Data System (ADS)

    Aylesworth, Grant R.

    Group E at Uaxactún has long been considered an ancient Maya observatory in which an observer could see the sun rise along architectural alignments at the solstices and equinoxes. E-Groups named for the architectural complex list identified in Group E at Uaxactún, typically consist of a large radial pyramid on their west side and three temples on a raised platform on their east side.

  16. Physical limits to magnetogenetics

    PubMed Central

    Meister, Markus

    2016-01-01

    This is an analysis of how magnetic fields affect biological molecules and cells. It was prompted by a series of prominent reports regarding magnetism in biological systems. The first claims to have identified a protein complex that acts like a compass needle to guide magnetic orientation in animals (Qin et al., 2016). Two other articles report magnetic control of membrane conductance by attaching ferritin to an ion channel protein and then tugging the ferritin or heating it with a magnetic field (Stanley et al., 2015; Wheeler et al., 2016). Here I argue that these claims conflict with basic laws of physics. The discrepancies are large: from 5 to 10 log units. If the reported phenomena do in fact occur, they must have causes entirely different from the ones proposed by the authors. The paramagnetic nature of protein complexes is found to seriously limit their utility for engineering magnetically sensitive cells. DOI: http://dx.doi.org/10.7554/eLife.17210.001 PMID:27529126

  17. Limits of computational biology.

    PubMed

    Bray, Dennis

    2015-01-01

    Are we close to a complete inventory of living processes so that we might expect in the near future to reproduce every essential aspect necessary for life? Or are there mechanisms and processes in cells and organisms that are presently inaccessible to us? Here I argue that a close examination of a particularly well-understood system--that of Escherichia coli chemotaxis--shows we are still a long way from a complete description. There is a level of molecular uncertainty, particularly that responsible for fine-tuning and adaptation to myriad external conditions, which we presently cannot resolve or reproduce on a computer. Moreover, the same uncertainty exists for any process in any organism and is especially pronounced and important in higher animals such as humans. Embryonic development, tissue homeostasis, immune recognition, memory formation, and survival in the real world, all depend on vast numbers of subtle variations in cell chemistry most of which are presently unknown or only poorly characterized. Overcoming these limitations will require us to not only accumulate large quantities of highly detailed data but also develop new computational methods able to recapitulate the massively parallel processing of living cells.

  18. Integrated Current Limiter

    NASA Astrophysics Data System (ADS)

    Pappalardo, S.; Alfonso, M. M.; Mirabella, I. B.

    2011-10-01

    The LCL has been extensively used in ESA scientific satellites and since a few years ago is being also the baseline device for earth observation satellites such as CRYOSAT 1 and 2, SENTINAL 1, 2 and 3, EARTWATCH, etc. It seems that the use of this LCL is also being considered as an alternative to fuse approach for commercial telecommunication satellites. Scope of this document is to provide a technical description of the Integrated Current Limiter device (shortly ICL later on) developed inside the domain of ESTECContract22049-09-NL-A Twith STMicroelectronics s.r.l. (ref. Invitation to Tender AO/1-5784/08/NL/A T). The design of the ICL device takes into account both ESA and power electronics designer's experience. This experience is more than 25 years long in Europe. The ICL design has been leaded in order to be fully compliant with the applicable specification issued by ESA and the major European power electronics manufacturers that have participated in its edition.

  19. Limits of computational biology

    PubMed Central

    Bray, Dennis

    2015-01-01

    Abstract Are we close to a complete inventory of living processes so that we might expect in the near future to reproduce every essential aspect necessary for life? Or are there mechanisms and processes in cells and organisms that are presently inaccessible to us? Here I argue that a close examination of a particularly well-understood system— that of Escherichia coli chemotaxis— shows we are still a long way from a complete description. There is a level of molecular uncertainty, particularly that responsible for fine-tuning and adaptation to myriad external conditions, which we presently cannot resolve or reproduce on a computer. Moreover, the same uncertainty exists for any process in any organism and is especially pronounced and important in higher animals such as humans. Embryonic development, tissue homeostasis, immune recognition, memory formation, and survival in the real world, all depend on vast numbers of subtle variations in cell chemistry most of which are presently unknown or only poorly characterized. Overcoming these limitations will require us to not only accumulate large quantities of highly detailed data but also develop new computational methods able to recapitulate the massively parallel processing of living cells. PMID:25318467

  20. Limited health literacy in advanced kidney disease.

    PubMed

    Taylor, Dominic M; Bradley, John A; Bradley, Clare; Draper, Heather; Johnson, Rachel; Metcalfe, Wendy; Oniscu, Gabriel; Robb, Matthew; Tomson, Charles; Watson, Chris; Ravanan, Rommel; Roderick, Paul

    2016-09-01

    Limited health literacy may reduce the ability of patients with advanced kidney disease to understand their disease and treatment and take part in shared decision making. In dialysis and transplant patients, limited health literacy has been associated with low socioeconomic status, comorbidity, and mortality. Here, we investigated the prevalence and associations of limited health literacy using data from the United Kingdom-wide Access to Transplantation and Transplant Outcome Measures (ATTOM) program. Incident dialysis, incident transplant, and transplant wait-listed patients ages 18 to 75 were recruited from 2011 to 2013 and data were collected from patient questionnaires and case notes. A score >2 in the Single-Item Literacy Screener was used to define limited health literacy. Univariate and multivariate analyses were performed to identify patient factors associated with limited health literacy. We studied 6842 patients, 2621 were incident dialysis, 1959 were wait-listed, and 2262 were incident transplant. Limited health literacy prevalence was 20%, 15%, and 12% in each group, respectively. Limited health literacy was independently associated with low socioeconomic status, poor English fluency, and comorbidity. However, transplant wait-listing, preemptive transplantation, and live-donor transplantation were associated with increasing health literacy. PMID:27521115

  1. Limited health literacy in advanced kidney disease.

    PubMed

    Taylor, Dominic M; Bradley, John A; Bradley, Clare; Draper, Heather; Johnson, Rachel; Metcalfe, Wendy; Oniscu, Gabriel; Robb, Matthew; Tomson, Charles; Watson, Chris; Ravanan, Rommel; Roderick, Paul

    2016-09-01

    Limited health literacy may reduce the ability of patients with advanced kidney disease to understand their disease and treatment and take part in shared decision making. In dialysis and transplant patients, limited health literacy has been associated with low socioeconomic status, comorbidity, and mortality. Here, we investigated the prevalence and associations of limited health literacy using data from the United Kingdom-wide Access to Transplantation and Transplant Outcome Measures (ATTOM) program. Incident dialysis, incident transplant, and transplant wait-listed patients ages 18 to 75 were recruited from 2011 to 2013 and data were collected from patient questionnaires and case notes. A score >2 in the Single-Item Literacy Screener was used to define limited health literacy. Univariate and multivariate analyses were performed to identify patient factors associated with limited health literacy. We studied 6842 patients, 2621 were incident dialysis, 1959 were wait-listed, and 2262 were incident transplant. Limited health literacy prevalence was 20%, 15%, and 12% in each group, respectively. Limited health literacy was independently associated with low socioeconomic status, poor English fluency, and comorbidity. However, transplant wait-listing, preemptive transplantation, and live-donor transplantation were associated with increasing health literacy.

  2. Peer Tutoring and Response Groups. What Works Clearinghouse Intervention Report

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2007

    2007-01-01

    "Peer Tutoring and Response Groups" aims to improve the language and achievement of English language learners by pairing or grouping students to work on a task. The students may be grouped by age or ability (English-only, bilingual, or limited English proficient) or the groups may be mixed. Both peer tutoring pairs and peer response groups…

  3. [Limits to euthanasia].

    PubMed

    de Kort, Susanne J

    2015-01-01

    A recent survey showed that less than half of Dutch physicians would find it conceivable to grant a request for euthanasia from a patient suffering from psychiatric disease or dementia, or who is tired of life. Because of a broader interpretation by the Regional Review Committees of the official criteria for due care, all recent cases of euthanasia in these specific groups of patients had been accepted. In this commentary it is argued that, following recent social developments in the Netherlands (including cuts in provision of care for the elderly and of mental health care, and a narrowed view about end-of-life issues), the official euthanasia criteria for due care are no longer suitable if we are to avoid a 'slippery slope' effect in cases such as those mentioned above. The criteria of a) a voluntary and well-considered request and b) absence of reasonable treatment alternatives are particularly under pressure. A plea is hold for a return to stricter interpretation of the criteria.

  4. [Limits to euthanasia].

    PubMed

    de Kort, Susanne J

    2015-01-01

    A recent survey showed that less than half of Dutch physicians would find it conceivable to grant a request for euthanasia from a patient suffering from psychiatric disease or dementia, or who is tired of life. Because of a broader interpretation by the Regional Review Committees of the official criteria for due care, all recent cases of euthanasia in these specific groups of patients had been accepted. In this commentary it is argued that, following recent social developments in the Netherlands (including cuts in provision of care for the elderly and of mental health care, and a narrowed view about end-of-life issues), the official euthanasia criteria for due care are no longer suitable if we are to avoid a 'slippery slope' effect in cases such as those mentioned above. The criteria of a) a voluntary and well-considered request and b) absence of reasonable treatment alternatives are particularly under pressure. A plea is hold for a return to stricter interpretation of the criteria. PMID:25970679

  5. Online User Group Directory

    ERIC Educational Resources Information Center

    Berger, Mary

    1978-01-01

    This list of U.S. and international online user groups includes contact persons and their addresses. The U.S. regions are divided according to the Medlars regional geographical breakdown. The user groups were formed so that data base producers or search service vendors could be invited to do training or give educational programs. (JPF)

  6. Grouping Information for Judgments

    ERIC Educational Resources Information Center

    Shah, Anuj K.; Oppenheimer, Daniel M.

    2011-01-01

    Models of cue weighting in judgment have typically focused on how decision-makers weight cues individually. Here, the authors propose that people might recognize and weight "groups" of cues. They examine how judgments change when decision-makers focus on cues individually or as parts of groups. Several experiments demonstrate that people can…

  7. Small Group Inquiry.

    ERIC Educational Resources Information Center

    Koller, Martin M.

    Learning in small groups is a practical way to bring about behavior change. The inquiry learning process is perceived to be the most natural and scientific way of learning. Skills developed include those of problem-solving task analysis, decision-making, value formation and adaptability. The art of small group interaction is developed. Factual…

  8. Our Deming Users' Group.

    ERIC Educational Resources Information Center

    Dinklocker, Christina

    1992-01-01

    After training in the Total Quality Management concept, a suburban Ohio school district created a Deming Users' Group to link agencies, individuals, and ideas. The group has facilitated ongoing school/business collaboration, networking among individuals from diverse school systems, mentoring and cooperative learning activities, and resource…

  9. Perceptual grouping across eccentricity.

    PubMed

    Tannazzo, Teresa; Kurylo, Daniel D; Bukhari, Farhan

    2014-10-01

    Across the visual field, progressive differences exist in neural processing as well as perceptual abilities. Expansion of stimulus scale across eccentricity compensates for some basic visual capacities, but not for high-order functions. It was hypothesized that as with many higher-order functions, perceptual grouping ability should decline across eccentricity. To test this prediction, psychophysical measurements of grouping were made across eccentricity. Participants indicated the dominant grouping of dot grids in which grouping was based upon luminance, motion, orientation, or proximity. Across trials, the organization of stimuli was systematically decreased until perceived grouping became ambiguous. For all stimulus features, grouping ability remained relatively stable until 40°, beyond which thresholds significantly elevated. The pattern of change across eccentricity varied across stimulus feature, in which stimulus scale, dot size, or stimulus size interacted with eccentricity effects. These results demonstrate that perceptual grouping of such stimuli is not reliant upon foveal viewing, and suggest that selection of dominant grouping patterns from ambiguous displays operates similarly across much of the visual field.

  10. Group Work. Research Brief

    ERIC Educational Resources Information Center

    Walker, Karen

    2010-01-01

    According to Johnson and Johnson, group work helps increase student retention and satisfaction, develops strong oral communication and social skills, as well as higher self-esteem (University of Minnesota, n.d.). Group work, when planned and implemented deliberately and thoughtfully helps students develop cognitive and leadership skills as well as…

  11. Training for Environmental Groups.

    ERIC Educational Resources Information Center

    Davies, J. Clarence; And Others

    This report examines the need for and resources available to environmental and conservation groups to develop skills in raising money and recruiting new members, managing an organization, communicating with the press, and analyzing policy issues. Data were obtained from 225 questionnaires returned by representative groups (411 were mailed), an…

  12. Democratic Group Work

    ERIC Educational Resources Information Center

    Laursen, Erik K.; Tate, Thomas F.

    2012-01-01

    For a century, democratic values have called for abandoning coercive approaches and teaching children and youth to be responsible citizens. The authors explore strategies for creating respectful environments and positive group cultures with challenging youth. They offer suggestions to adult group facilitators to support youth in developing…

  13. The Thursday Night Group.

    ERIC Educational Resources Information Center

    History and Social Science Teacher, 1985

    1985-01-01

    A Los Angeles based grassroots organization, the Thursday Night Group, promotes the vision that the world can be different and that we all--adults and children--can do something to find solutions to the nuclear threat. How the group serves as a resource to elementary and secondary schools is described. (RM)

  14. Reading Groups: Problems, Solutions.

    ERIC Educational Resources Information Center

    Worthington, Jim

    The practice of grouping children of similar ability for reading instruction is as much a part of the classroom as the chalkboard, yet for decades research into classroom practice has raised serious questions about ability grouping. A research project using the meta-analysis approach to analyze more than 50 research studies concluded that ability…

  15. Physically detached 'compact groups'

    NASA Technical Reports Server (NTRS)

    Hernquist, Lars; Katz, Neal; Weinberg, David H.

    1995-01-01

    A small fraction of galaxies appear to reside in dense compact groups, whose inferred crossing times are much shorter than a Hubble time. These short crossing times have led to considerable disagreement among researchers attempting to deduce the dynamical state of these systems. In this paper, we suggest that many of the observed groups are not physically bound but are chance projections of galaxies well separated along the line of sight. Unlike earlier similar proposals, ours does not require that the galaxies in the compact group be members of a more diffuse, but physically bound entity. The probability of physically separated galaxies projecting into an apparent compact group is nonnegligible if most galaxies are distributed in thin filaments. We illustrate this general point with a specific example: a simulation of a cold dark matter universe, in which hydrodynamic effects are included to identify galaxies. The simulated galaxy distribution is filamentary and end-on views of these filaments produce apparent galaxy associations that have sizes and velocity dispersions similar to those of observed compact groups. The frequency of such projections is sufficient, in principle, to explain the observed space density of groups in the Hickson catalog. We discuss the implications of our proposal for the formation and evolution of groups and elliptical galaxies. The proposal can be tested by using redshift-independent distance estimators to measure the line-of-sight spatial extent of nearby compact groups.

  16. Fairness and Ability Grouping.

    ERIC Educational Resources Information Center

    Strike, Kenneth A.

    1983-01-01

    A recent controversy regarding ability grouping is that it is often perceived as a means whereby racial or class bias can be subtly transformed into mechanisms of discrimination which exhibit the appearance of fairness and objectivity. This article addresses the question of fairness in ability grouping. (CJB)

  17. Leukosis/Sarcoma Group

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The leukosis/sarcoma (L/S) group of diseases designates a variety of transmissible benign and malignant neoplasms of chickens caused by members that belong to the family Retroviridae. Lymphoid leukosis has been the most common form of L/S group of diseases seen in field flocks, although myeloid leuk...

  18. Limits to Tidal Power

    NASA Astrophysics Data System (ADS)

    Garrett, C.

    2008-12-01

    Ocean tides have been proposed as a source of renewable energy, though the maximum available power may be shown to be only a fraction of the present dissipation rate of 3.5 TW, which is small compared with global insolation (nearly 105 TW), wind dissipation (103 TW), and even human power usage of 15 TW. Nonetheless, tidal power could be a useful contributor in some locations. Traditional use of tidal power, involving the trapping of water behind a barrage at high tide, can produce an average power proportional to the area of the headpond and the square of the tidal range; the power density is approximately 6 W per square meter for a tidal range of 10 m. Capital costs and fears of environmental damage have put barrage schemes in disfavor, with interest turning to the exploitation of strong tidal currents, using turbines in a manner similar to wind turbines. There is a limit to the available power, however, as adding turbines reduces the flow, ultimately reducing the power. For sinusoidal forcing of flow in a channel connecting two large open basins, the maximum available power may be shown to be given approximately by 0.2ρ g a Q_max, where ρ is the water density, g gravity, a the amplitude of the tidal sea level difference along the channel, and Q_max is the maximum volume flux in the natural state. The same formula applies if the channel is the entrance to a semi-enclosed basin, with a now the amplitude of the external tide. A flow reduction of approximately 40% is typically associated with the maximum power extraction. The power would be reduced if only smaller environmental changes are acceptable, and reduced further by drag on supporting structures, dissipation in turbine wakes, and internal inefficiencies. It can be suggested that the best use of strong, cold, tidal currents is to provide cooling water for nuclear reactors.

  19. Computations of Eisenstein series on Fuchsian groups

    NASA Astrophysics Data System (ADS)

    Avelin, Helen

    2008-09-01

    We present numerical investigations of the value distribution and distribution of Fourier coefficients of the Eisenstein series E(z;s) on arithmetic and non-arithmetic Fuchsian groups. Our numerics indicate a Gaussian limit value distribution for a real-valued rotation of E(z;s) as operatorname{Re} sD1/2 , operatorname{Im} sto infty and also, on non-arithmetic groups, a complex Gaussian limit distribution for E(z;s) when operatorname{Re} s>1/2 near 1/2 and operatorname{Im} sto infty , at least if we allow operatorname{Re} sto 1/2 at some rate. Furthermore, on non-arithmetic groups and for fixed s with operatorname{Re} s ge 1/2 near 1/2 , our numerics indicate a Gaussian limit distribution for the appropriately normalized Fourier coefficients.

  20. Perceiving persons and groups.

    PubMed

    Hamilton, D L; Sherman, S J

    1996-04-01

    This article analyzes the similarities and differences in forming impressions of individuals and in developing conceptions of groups. In both cases, the perceiver develops a mental conception of the target (individual or group) on the basis of available information and uses that information to make judgments about that person or group. However, a review of existing evidence reveals differences in the outcomes of impressions formed of individual and group targets, even when those impressions are based on the very same behavioral information. A model is proposed to account for these differences. The model emphasizes the role of differing expectancies of unity and coherence in individual and group targets, which in turn engage different mechanisms for processing information and making judgments. Implications of the model are discussed.

  1. Perceiving persons and groups.

    PubMed

    Hamilton, D L; Sherman, S J

    1996-04-01

    This article analyzes the similarities and differences in forming impressions of individuals and in developing conceptions of groups. In both cases, the perceiver develops a mental conception of the target (individual or group) on the basis of available information and uses that information to make judgments about that person or group. However, a review of existing evidence reveals differences in the outcomes of impressions formed of individual and group targets, even when those impressions are based on the very same behavioral information. A model is proposed to account for these differences. The model emphasizes the role of differing expectancies of unity and coherence in individual and group targets, which in turn engage different mechanisms for processing information and making judgments. Implications of the model are discussed. PMID:8637962

  2. Groups and Violence

    NASA Astrophysics Data System (ADS)

    Bhavnani, Ravi; Miodownik, Dan; Riolo, Rick

    Violence can take place along a multitude of cleavages, e.g., (1) between political groups like the Kach Movement, pitting West Bank settlers against Israeli governments supporting the land-for-peace agenda; (2) between religious groups, such as Christians and Muslims in the Nigerian cities of Jos and Kaduna; (3) along class lines, as in India between Dalits and members of the Brahminical upper castes, upwardly mobile intermediate castes, and even other backward castes such as the Thevars; and (4) between ethnic groups such as the Hutu and Tutsi, both within and across state boundaries in Rwanda and neighboring Burundi.

  3. Impedance group summary

    NASA Astrophysics Data System (ADS)

    Blaskiewicz, M.; Dooling, J.; Dyachkov, M.; Fedotov, A.; Gluckstern, R.; Hahn, H.; Huang, H.; Kurennoy, S.; Linnecar, T.; Shaposhnikova, E.; Stupakov, G.; Toyama, T.; Wang, J. G.; Weng, W. T.; Zhang, S. Y.; Zotter, B.

    1999-12-01

    The impedance working group was charged to reply to the following 8 questions relevant to the design of high-intensity proton machines such as the SNS or the FNAL driver. These questions were first discussed one by one in the whole group, then each ne of them assigned to one member to summarize. On the lst morning these contributions were publicly read, re-discussed and re-written where required—hence they are not the opinion of a particular person, but rather the averaged opinion of all members of the working group. (AIP)

  4. Ionospheric limitations to time transfer by satellite

    NASA Technical Reports Server (NTRS)

    Knowles, S. H.

    1983-01-01

    The ionosphere can contribute appreciable group delay and phase change to radio signals traversing it; this can constitute a fundamental limitation to the accuracy of time and frequency measurements using satellites. Because of the dispersive nature of the ionosphere, the amount of delay is strongly frequency-dependent. Ionospheric compensation is necessary for the most precise time transfer and frequency measurements, with a group delay accuracy better than 10 nanoseconds. A priori modeling is not accurate to better than 25%. The dual-frequency compensation method holds promise, but has not been rigorously experimentally tested. Irregularities in the ionosphere must be included in the compensation process.

  5. Supermembrane limit of Yang-Mills theory

    NASA Astrophysics Data System (ADS)

    Lechtenfeld, Olaf; Popov, Alexander D.

    2016-02-01

    We consider Yang-Mills theory with N = 1 super-translation group in eleven auxiliary dimensions as the structure group. The gauge theory is defined on a direct product manifold Σ3 × S1, where Σ3 is a three-dimensional Lorentzian manifold and S1 is a circle. We show that in the infrared limit, when the metric on S1 is scaled down, the Yang-Mills action supplemented by a Wess-Zumino-type term reduces to the action of an M2-brane.

  6. Determining the least limiting water range using limited soil data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Least Limiting Water Range (LLWR) is a useful tool to evaluate changes in soil physical condition caused by changing soil management. It incorporates limitations to plant growth based on limiting aeration, water holding capacity and soil strength. A disadvantage of the LLWR is the need to determ...

  7. Instrumentation Working Group Summary

    NASA Technical Reports Server (NTRS)

    Zaller, Michelle; Miake-Lye, Richard

    1999-01-01

    The Instrumentation Working Group compiled a summary of measurement techniques applicable to gas turbine engine aerosol precursors and particulates. An assessment was made of the limits, accuracy, applicability, and technology readiness of the various techniques. Despite advances made in emissions characterization of aircraft engines, uncertainties still exist in the mechanisms by which aerosols and particulates are produced in the near-field engine exhaust. To adequately assess current understanding of the formation of sulfuric acid aerosols in the exhaust plumes of gas turbine engines, measurements are required to determine the degree and importance of sulfur oxidation in the turbine and at the engine exit. Ideally, concentrations of all sulfur species would be acquired, with emphasis on SO2 and SO3. Numerous options exist for extractive and non-extractive measurement of SO2 at the engine exit, most of which are well developed. SO2 measurements should be performed first to place an upper bound on the percentage of SO2 oxidation. If extractive and non-extractive techniques indicate that a large amount of the fuel sulfur is not detected as SO2, then efforts are needed to improve techniques for SO3 measurements. Additional work will be required to account for the fuel sulfur in the engine exhaust. Chemical Ionization Mass Spectrometry (CI-MS) measurements need to be pursued, although a careful assessment needs to be made of the sampling line impact on the extracted sample composition. Efforts should also be placed on implementing non-intrusive techniques and extending their capabilities by maximizing exhaust coverage for line-of-sight measurements, as well as development of 2-D techniques, where feasible. Recommendations were made to continue engine exit and combustor measurements of particulates. Particulate measurements should include particle size distribution, mass fraction, hydration properties, and volatile fraction. However, methods to ensure that unaltered

  8. Limitations in life participation and independence due to secondary conditions.

    PubMed

    Koritsas, Stella; Iacono, Teresa

    2009-11-01

    The effects of secondary conditions across adults with autism, Down syndrome, and cerebral palsy were explored in terms of overall limitation in life participation and independence, changes over time, and the degree and nature of limitation in specific secondary conditions. Information was obtained for 35 adults with autism, 49 with Down syndrome, and 29 with cerebral palsy (N = 113). Caregivers completed a questionnaire exploring secondary conditions on two occasions. Participants with cerebral palsy experienced the greatest overall limitations of the three groups. This finding is due to several secondary conditions. There were no changes in limitation scores over time. Implications related to health care for these groups are discussed.

  9. Group Music Training and Children's Prosocial Skills

    PubMed Central

    Schellenberg, E. Glenn; Corrigall, Kathleen A.; Dys, Sebastian P.; Malti, Tina

    2015-01-01

    We investigated if group music training in childhood is associated with prosocial skills. Children in 3rd or 4th grade who attended 10 months of music lessons taught in groups were compared to a control group of children matched for socio-economic status. All children were administered tests of prosocial skills near the beginning and end of the 10-month period. Compared to the control group, children in the music group had larger increases in sympathy and prosocial behavior, but this effect was limited to children who had poor prosocial skills before the lessons began. The effect was evident even when the lessons were compulsory, which minimized the role of self-selection. The results suggest that group music training facilitates the development of prosocial skills. PMID:26506414

  10. Group Music Training and Children's Prosocial Skills.

    PubMed

    Schellenberg, E Glenn; Corrigall, Kathleen A; Dys, Sebastian P; Malti, Tina

    2015-01-01

    We investigated if group music training in childhood is associated with prosocial skills. Children in 3rd or 4th grade who attended 10 months of music lessons taught in groups were compared to a control group of children matched for socio-economic status. All children were administered tests of prosocial skills near the beginning and end of the 10-month period. Compared to the control group, children in the music group had larger increases in sympathy and prosocial behavior, but this effect was limited to children who had poor prosocial skills before the lessons began. The effect was evident even when the lessons were compulsory, which minimized the role of self-selection. The results suggest that group music training facilitates the development of prosocial skills.

  11. Group Music Training and Children's Prosocial Skills.

    PubMed

    Schellenberg, E Glenn; Corrigall, Kathleen A; Dys, Sebastian P; Malti, Tina

    2015-01-01

    We investigated if group music training in childhood is associated with prosocial skills. Children in 3rd or 4th grade who attended 10 months of music lessons taught in groups were compared to a control group of children matched for socio-economic status. All children were administered tests of prosocial skills near the beginning and end of the 10-month period. Compared to the control group, children in the music group had larger increases in sympathy and prosocial behavior, but this effect was limited to children who had poor prosocial skills before the lessons began. The effect was evident even when the lessons were compulsory, which minimized the role of self-selection. The results suggest that group music training facilitates the development of prosocial skills. PMID:26506414

  12. Setting Win Limits: An Alternative Approach to "Responsible Gambling"?

    PubMed

    Walker, Douglas M; Litvin, Stephen W; Sobel, Russell S; St-Pierre, Renée A

    2015-09-01

    Social scientists, governments, and the casino industry have all emphasized the need for casino patrons to "gamble responsibly." Strategies for responsible gambling include self-imposed time limits and loss limits on gambling. Such strategies help prevent people from losing more than they can afford and may help prevent excessive gambling behavior. Yet, loss limits also make it more likely that casino patrons leave when they are losing. Oddly, the literature makes no mention of "win limits" as a potential approach to responsible gambling. A win limit would be similar to a loss limit, except the gambler would leave the casino upon reaching a pre-set level of winnings. We anticipate that a self-imposed win limit will reduce the gambler's average loss and, by default, also reduce the casino's profit. We test the effect of a self-imposed win limit by running slot machine simulations in which the treatment group of players has self-imposed and self-enforced win and loss limits, while the control group has a self-imposed loss limit or no limit. We find that the results conform to our expectations: the win limit results in improved player performance and reduced casino profits. Additional research is needed, however, to determine whether win limits could be a useful component of a responsible gambling strategy.

  13. InterGroup Protocols

    2003-04-02

    Existing reliable ordered group communication protocols have been developed for local-area networks and do not in general scale well to a large number of nodes and wide-area networks. The InterGroup suite of protocols is a scalable group communication system that introduces an unusual approach to handling group membership, and supports a receiver-oriented selection of service. The protocols are intended for a wide-area network, with a large number of nodes, that has highly variable delays andmore » a high message loss rate, such as the Internet. The levels of the message delivery service range from unreliable unordered to reliable timestamp ordered.« less

  14. Building Group Recognition.

    ERIC Educational Resources Information Center

    Chartier, George

    1994-01-01

    Discusses the value of name recognition for theater companies. Describes steps toward identity and recognition, analyzing the group, the mission statement, symbolic logic, designing and identity, developing a communications plan, and meaningful activities. (SR)

  15. RAS Laboratory Groups

    Cancer.gov

    The RAS Initiative uses multiple technologies to attack RAS-driven cancers. The resources of the Frederick National Lab allocated to the RAS Hub are organized into seven laboratory groups, each contributing to the collaborative effort.

  16. Functional Group Analysis.

    ERIC Educational Resources Information Center

    Smith, Walter T., Jr.; Patterson, John M.

    1980-01-01

    Discusses analytical methods selected from current research articles. Groups information by topics of general interest, including acids, aldehydes and ketones, nitro compounds, phenols, and thiols. Cites 97 references. (CS)

  17. SRNL Atmospheric Technologies Group

    ScienceCinema

    Viner, Brian; Parker, Matthew J.

    2016-07-12

    The Savannah River National Laboratory, Atmospheric Technologies Group, conducts a best-in class Applied Meteorology Program to ensure the Department of Energy’s Savannah River Site is operated safely and complies with stringent environmental regulations.

  18. UnitedHealth Group

    Cancer.gov

    UnitedHealth Group provides accessible and affordable services, improved quality of care, coordinated health care efforts, and a supportive environment for shared decision making between patients and their physicians.

  19. Making Group Decisions.

    ERIC Educational Resources Information Center

    Drennen, Nancy Hungerford

    1982-01-01

    For greater effectiveness, attention should be paid to how group decisions are made. The process of consensus-seeking encourages appraisal of more information and provides a broader range of potential alternatives. (SK)

  20. Gluten Intolerance Group

    MedlinePlus

    ... The Gluten Intolerance Group (GIG) empowers the gluten-free community through consumer support, advocacy, and education. • SUPPORT GIG • ... about the events taking place in your gluten-free community. Find >> Products From breads and pastas to pet ...

  1. Group Support Systems (GSS)

    NASA Technical Reports Server (NTRS)

    Hamel, Gary P.; Wijesinghe, R.

    1996-01-01

    Groupware is a term describing an emerging computer software technology enhancing the ability of people to work together as a group, (a software driven 'group support system'). This project originated at the beginning of 1992 and reports were issued describing the activity through May 1995. These reports stressed the need for process as well as technology. That is, while the technology represented a computer assisted method for groups to work together, the Group Support System (GSS) technology als required an understanding of the facilitation process electronic meetings demand. Even people trained in traditional facilitation techniques did not necessarily aimlessly adopt groupware techniques. The latest phase of this activity attempted to (1) improve the facilitation process by developing training support for a portable groupware computer system, and (2) to explore settings and uses for the portable groupware system using different software, such as Lotus Notes.

  2. Group B streptococcus - pregnancy

    MedlinePlus

    ... PS, Baker CJ. Group B streptococcal infections. In: Cherry J, Harrison GJ, Kaplan SL, Steinbach WJ, Hotez PJ, eds. Feigin and Cherry's Textbook of Pediatric Infectious Diseases. 7th ed. Philadelphia, ...

  3. Parton Distributions Working Group

    SciTech Connect

    de Barbaro, L.; Keller, S. A.; Kuhlmann, S.; Schellman, H.; Tung, W.-K.

    2000-07-20

    This report summarizes the activities of the Parton Distributions Working Group of the QCD and Weak Boson Physics workshop held in preparation for Run II at the Fermilab Tevatron. The main focus of this working group was to investigate the different issues associated with the development of quantitative tools to estimate parton distribution functions uncertainties. In the conclusion, the authors introduce a Manifesto that describes an optimal method for reporting data.

  4. Magnetograph group summary

    NASA Technical Reports Server (NTRS)

    Jones, Harrison P.

    1989-01-01

    The Magnetograph Group focussed on the techniques and many practical problems of interleaving ground-based measurements of magnetic fields from diverse sites and instruments to address the original scientific objectives. The predominant view of the discussion group was that present instrumentation and analysis resources do not warrant immediate, specific plans for further worldwide campaigns of cooperative magnetograph observing. The several reasons for this view, together with many caveats, qualifications, and suggestions for future work are presented.

  5. Group Capability Model

    NASA Technical Reports Server (NTRS)

    Olejarski, Michael; Appleton, Amy; Deltorchio, Stephen

    2009-01-01

    The Group Capability Model (GCM) is a software tool that allows an organization, from first line management to senior executive, to monitor and track the health (capability) of various groups in performing their contractual obligations. GCM calculates a Group Capability Index (GCI) by comparing actual head counts, certifications, and/or skills within a group. The model can also be used to simulate the effects of employee usage, training, and attrition on the GCI. A universal tool and common method was required due to the high risk of losing skills necessary to complete the Space Shuttle Program and meet the needs of the Constellation Program. During this transition from one space vehicle to another, the uncertainty among the critical skilled workforce is high and attrition has the potential to be unmanageable. GCM allows managers to establish requirements for their group in the form of head counts, certification requirements, or skills requirements. GCM then calculates a Group Capability Index (GCI), where a score of 1 indicates that the group is at the appropriate level; anything less than 1 indicates a potential for improvement. This shows the health of a group, both currently and over time. GCM accepts as input head count, certification needs, critical needs, competency needs, and competency critical needs. In addition, team members are categorized by years of experience, percentage of contribution, ex-members and their skills, availability, function, and in-work requirements. Outputs are several reports, including actual vs. required head count, actual vs. required certificates, CGI change over time (by month), and more. The program stores historical data for summary and historical reporting, which is done via an Excel spreadsheet that is color-coded to show health statistics at a glance. GCM has provided the Shuttle Ground Processing team with a quantifiable, repeatable approach to assessing and managing the skills in their organization. They now have a common

  6. Swept group delay measurement

    NASA Technical Reports Server (NTRS)

    Trowbridge, D. L. (Inventor)

    1978-01-01

    Direct recording of group delay measurements on a system under temperature and stress tests employs modulated carrier frequency sweep over an S or X band. Reference path and test paths to separate detectors utilize a power divider e.g., a directional coupler or a hybrid T junction. An initially balanced phase comparator is swept in frequency by modulated carrier over the band of interest for different conditions of temperature and/or mechanical stress to obtain characteristic group delay curves.

  7. Blood groups and filariasis.

    PubMed

    Kumar, H; Santhanam, S

    1989-01-01

    Only a little is known about the studies done with filariasis in relation to blood groups. The present communication reports the results of a preliminary study carried out to investigate any relationship of ABO and Rho(D) blood groups in persons with circulating microfilariae (mf) in blood and with disease manifestations compared with healthy normal controls within a population in similar epidemiological and ecological conditions. Blood groups ABO and Rho(D) were investigated among 271 persons with filarial disease and 172 normal subjects from an endemic area of bancroftian filariasis. No relationship was observed between infection and blood groups. It appeared that blood groups and filarial infection were independent of each other. Also the sex of the individual and stage of the infection, i.e. persons with circulating mf only without manifestations and persons with established manifestation without mf, has no bearing on blood group inheritance. There were 95.05% of Rh-positive and 4.95% of Rh-negative persons in the whole studied population. The observations are similar to other studies.

  8. Limits to Open Class Performance?

    NASA Technical Reports Server (NTRS)

    Bowers, Albion H.

    2007-01-01

    This viewgraph presentation describes the limits to open class performance. The contents include: 1) Standard Class; 2) 15m/Racing Class; 3) Open Class; and 4) Design Solutions associated with assumptions, limiting parameters, airfoil performance, current trends, and analysis.

  9. COMMENTARY:Limits to adaptation

    SciTech Connect

    Preston, Benjamin L

    2013-01-01

    An actor-centered, risk-based approach to defining limits to social adaptation provides a useful analytic framing for identifying and anticipating these limits and informing debates over society s responses to climate change.

  10. Facilities removal working group

    SciTech Connect

    1997-03-01

    This working group`s first objective is to identify major economic, technical, and regulatory constraints on operator practices and decisions relevant to offshore facilities removal. Then, the group will try to make recommendations as to regulatory and policy adjustments, additional research, or process improvements and/or technological advances, that may be needed to improve the efficiency and effectiveness of the removal process. The working group will focus primarily on issues dealing with Gulf of Mexico platform abandonments. In order to make the working group sessions as productive as possible, the Facilities Removal Working Group will focus on three topics that address a majority of the concerns and/or constraints relevant to facilities removal. The three areas are: (1) Explosive Severing and its Impact on Marine Life, (2) Pile and Conductor Severing, and (3) Deep Water Abandonments This paper will outline the current state of practice in the offshore industry, identifying current regulations and specific issues encountered when addressing each of the three main topics above. The intent of the paper is to highlight potential issues for panel discussion, not to provide a detailed review of all data relevant to the topic. Before each panel discussion, key speakers will review data and information to facilitate development and discussion of the main issues of each topic. Please refer to the attached agenda for the workshop format, key speakers, presentation topics, and panel participants. The goal of the panel discussions is to identify key issues for each of the three topics above. The working group will also make recommendations on how to proceed on these key issues.

  11. Coordinating Group report

    SciTech Connect

    Not Available

    1994-01-01

    In December 1992, western governors and four federal agencies established a Federal Advisory Committee to Develop On-site Innovative Technologies for Environmental Restoration and Waste Management (the DOIT Committee). The purpose of the Committee is to advise the federal government on ways to improve waste cleanup technology development and the cleanup of federal sites in the West. The Committee directed in January 1993 that information be collected from a wide range of potential stakeholders and that innovative technology candidate projects be identified, organized, set in motion, and evaluated to test new partnerships, regulatory approaches, and technologies which will lead to improve site cleanup. Five working groups were organized, one to develop broad project selection and evaluation criteria and four to focus on specific contaminant problems. A Coordinating Group comprised of working group spokesmen and federal and state representatives, was set up to plan and organize the routine functioning of these working groups. The working groups were charged with defining particular contaminant problems; identifying shortcomings in technology development, stakeholder involvement, regulatory review, and commercialization which impede the resolution of these problems; and identifying candidate sites or technologies which could serve as regional innovative demonstration projects to test new approaches to overcome the shortcomings. This report from the Coordinating Group to the DOIT Committee highlights the key findings and opportunities uncovered by these fact-finding working groups. It provides a basis from which recommendations from the DOIT Committee to the federal government can be made. It also includes observations from two public roundtables, one on commercialization and another on regulatory and institutional barriers impeding technology development and cleanup.

  12. Crop grouping: a proposal for public aquaculture.

    PubMed

    Gingerich, W H; Stehly, G R; Clark, K J; Hayton, W L

    1998-01-01

    Production in US aquaculture is limited by the few FDA-approved drugs available for use. The problem is compounded by the high costs and long time frames associated with extending the approved label of an existing drug to treat additional fish species. An FDA approved crop grouping plan could significantly reduce the costs associated with extending or expanding the label of a currently approved drug to other species. Before FDA could sanction such a plan, they require scientific data with which to make an informed decision. Under a crop grouping plan, a surrogate fish species would represent a single group of fish for the purposes of gaining drug approvals. The concept, if practical, would conserve substantial public resources expended to gain drug approvals and yet give regulators assurance that the extended label use provides necessary regulatory safeguards to protect human food safety and the environment. A crop grouping plan should include development of a data base that is sufficiently sensitive to discriminate differences of one group from another and yet would be able to identify potential similarities between like-species for grouping. The proposed crop grouping action plan should include data sets for fish grouped by temperature preference, activity level, and phylogenetic classification. Initially, two representative species would be identified for testing as surrogates for candidate groups; rainbow trout representing a coldwater, active, and conservative phylogenetic group, and channel catfish representing a warmwater, relatively sedentary and more phylogenetically advanced group. Additional species representing more primitive (sturgeon) and more advanced (striped bass and walleye) groups would be added. A waterborne (benzocaine) and an orally administered drug (sarafloxacin) would initially be tested among the major species groups. The integrity of the group will be tested by comparing the variability of response between major species against

  13. Faint dwarfs in nearby groups

    SciTech Connect

    Speller, Ryan; Taylor, James E. E-mail: taylor@uwaterloo.ca

    2014-06-20

    The number and distribution of dwarf satellite galaxies remain a critical test of cold dark matter-dominated structure formation on small scales. Until recently, observational information about galaxy formation on these scales has been limited mainly to the Local Group. We have searched for faint analogues of Local Group dwarfs around nearby bright galaxies, using a spatial clustering analysis of the photometric catalog of the Sloan Digital Sky Survey (SDSS) Data Release 8. Several other recent searches of SDSS have detected clustered satellite populations down to Δm{sub r} ≡ (m{sub r,} {sub sat} – m{sub r,} {sub main}) ∼ 6-8, using photometric redshifts to reduce background contamination. SDSS photometric redshifts are relatively imprecise, however, for faint and nearby galaxies. Instead, we use angular size to select potential nearby dwarfs and consider only the nearest isolated bright galaxies as primaries. As a result, we are able to detect an excess clustering signal from companions down to Δm{sub r} = 12, 4 mag fainter than most recent studies. We detect an overdensity of objects at separations <400 kpc, corresponding to about 4.6 ± 0.5 satellites per central galaxy, consistent with the satellite abundance expected from the Local Group, given our selection function. Although the sample of satellites detected is incomplete by construction, since it excludes the least and most compact dwarfs, this detection provides a lower bound on the average satellite luminosity function, down to luminosities corresponding to the faintest ''classical'' dwarfs of the Local Group.

  14. Updates on Force Limiting Improvements

    NASA Technical Reports Server (NTRS)

    Kolaini, Ali R.; Scharton, Terry

    2013-01-01

    The following conventional force limiting methods currently practiced in deriving force limiting specifications assume one-dimensional translation source and load apparent masses: Simple TDOF model; Semi-empirical force limits; Apparent mass, etc.; Impedance method. Uncorrelated motion of the mounting points for components mounted on panels and correlated, but out-of-phase, motions of the support structures are important and should be considered in deriving force limiting specifications. In this presentation "rock-n-roll" motions of the components supported by panels, which leads to a more realistic force limiting specifications are discussed.

  15. Illinois Wind Workers Group

    SciTech Connect

    David G. Loomis

    2012-05-28

    The Illinois Wind Working Group (IWWG) was founded in 2006 with about 15 members. It has grown to over 200 members today representing all aspects of the wind industry across the State of Illinois. In 2008, the IWWG developed a strategic plan to give direction to the group and its activities. The strategic plan identifies ways to address critical market barriers to the further penetration of wind. The key to addressing these market barriers is public education and outreach. Since Illinois has a restructured electricity market, utilities no longer have a strong control over the addition of new capacity within the state. Instead, market acceptance depends on willing landowners to lease land and willing county officials to site wind farms. Many times these groups are uninformed about the benefits of wind energy and unfamiliar with the process. Therefore, many of the project objectives focus on conferences, forum, databases and research that will allow these stakeholders to make well-educated decisions.

  16. Instructions to working groups

    NASA Technical Reports Server (NTRS)

    Foushee, H. Clayton

    1987-01-01

    The key to the success of this workshop is your active participation in the working group process. The goals of this workshop are to address four major questions regarding Cockpit Resource Management (CRM) Training. To some extent the working group topic areas parallel these issues, but in some cases they do not. However, it is important for all of the working groups to keep these general questions in mind during their deliberations: (1) What are the essential elements of an optimal CRM Training program; (2) What are the strengths and weaknesses of current approaches to CRM Training; (3) How can CRM Training best be implemented, and what barriers exist; and (4) Is CRM Training effective, do we know, and if not, how can we find out.

  17. [Blood groups and disease].

    PubMed

    Prokop, O

    1986-09-01

    The inquiry for the sense of blood group polymorphisms (enzyme groups and serum groups included) and their significance for the constitution and also disposition to diseases is for the time being absolutely legitimate. But it is shown that the field--scarcely a new hereditary blood factor has been detected--becomes a subject of speculations, possibly of the teleological kind: "For which purpose is the factor existing?", or even "Why has God made up the factor?". The hypotheses developing on that are often extremely suggestive and incorrect hypotheses on the first opportunity sometimes reappear like a "cork-tumbler". Finally only a few hard facts remain. This is shown with the help of the systems AB0, Duffy, HLA, Hp and Pi. PMID:2947391

  18. Group Psychotherapy in Sweden.

    PubMed

    Ahlin, Göran

    2015-10-01

    The paper presents an overview of the national developments of group psychotherapy (GPS) in Sweden during the period from World War II until the present time. Methods and concepts, imported primarily from England and the United States, inspired trainings and widespread psychodynamic and group analytic applications in schools, health treatment, and social care. Education in psychotherapy and GPS at universities opened new therapeutic and vocational areas during the period 1970-2005. Increasing criticism of psychodynamics, as in other Western societies, but more radical in Sweden, has in the last decades made group analytic GPS diminish in favor of cognitive behavioral therapy models. Prospects for GPS further development may presently look bleak but, in a longer perspective, are promising.

  19. Factorizations in finite groups

    SciTech Connect

    Kulikov, Viktor S

    2013-02-28

    A necessary condition for uniqueness of factorizations of elements of a finite group G with factors belonging to a union of some conjugacy classes of G is given. This condition is sufficient if the number of factors belonging to each conjugacy class is big enough. The result is applied to the problem on the number of irreducible components of the Hurwitz space of degree d marked coverings of P{sup 1} with given Galois group G and fixed collection of local monodromies. Bibliography: 9 titles.

  20. Upgraded Coal Interest Group

    SciTech Connect

    Evan Hughes

    2009-01-08

    The Upgraded Coal Interest Group (UCIG) is an EPRI 'users group' that focuses on clean, low-cost options for coal-based power generation. The UCIG covers topics that involve (1) pre-combustion processes, (2) co-firing systems and fuels, and (3) reburn using coal-derived or biomass-derived fuels. The UCIG mission is to preserve and expand the economic use of coal for energy. By reducing the fuel costs and environmental impacts of coal-fired power generation, existing units become more cost effective and thus new units utilizing advanced combustion technologies are more likely to be coal-fired.

  1. Bell, group and tangle

    SciTech Connect

    Solomon, A. I.

    2010-03-15

    The 'Bell' of the title refers to bipartite Bell states, and their extensions to, for example, tripartite systems. The 'Group' of the title is the Braid Group in its various representations; while 'Tangle' refers to the property of entanglement which is present in both of these scenarios. The objective of this note is to explore the relation between Quantum Entanglement and Topological Links, and to show that the use of the language of entanglement in both cases is more than one of linguistic analogy.

  2. Group caregiver language checklist.

    PubMed

    Pearson, M E; Shelton, D; Pearson, A A; Miller, M

    1992-01-01

    Because young children with language disabilities frequently are placed in group-care settings, there is a need to make judgments concerning the language environment of those settings. The GCLC is offered as one procedure for assessment of the language environment provided by the caregiver(s) in a group setting. The assessment provides information that may assist in matching the environment to a particular child's needs and may provide a basis for assisting caregivers in improving the language environment and addressing a child's needs. The authors welcome comments from the readers.

  3. Microdosimetric basis for exposure limits.

    PubMed

    Brackenbush, L W; Braby, L A

    1988-08-01

    Consideration of the energy deposited by ionizing radiation in microscopic volumes has led to new insights into dosimetric concepts at the levels of interest in radiation protection. Large amounts of energy are deposited by the passage of low linear-energy-transfer (LET)-charged particles through small volumes. If a typical cell nucleus is considered to be about 7 micron, at an exposure rate of 2.5 X 10(-1) C kg-1 h-1 (1 mR hr-1) from a 60Co irradiation, the average cell nucleus receives one energy deposition event every 12.5 d. Biological processes, which modify radiation damage, typically occur in a few minutes to a few hours. Thus, at occupational exposure levels it is probably the irreparable or misrepaired effects of irradiation that determine the biological consequences. One goal of dosimetry is to measure the incident radiation, making it possible to predict biological risk and set meaningful exposure limits. These measurements must relate to the energy depositions that are responsible for radiation effects at low dose rates, yet the dosimetry system must not be excessively complex to allow use by operational health physicists. Furthermore, our description of the irradiation should be directly measurable. The use of quality factors based upon the energy deposition in a 1-micron-diameter volume of tissue as prescribed in International Commission on Radiation Units Report No. 40 (Joint Task Group 1986) satisfies these requirements. Instrumentation based upon measurement of lineal energy has already been successfully used in health-physics applications. Future changes in the quality factor can be accommodated by changing the algorithm in these microprocessor-based instruments. PMID:3410692

  4. Microdosimetric basis for exposure limits.

    PubMed

    Brackenbush, L W; Braby, L A

    1988-08-01

    Consideration of the energy deposited by ionizing radiation in microscopic volumes has led to new insights into dosimetric concepts at the levels of interest in radiation protection. Large amounts of energy are deposited by the passage of low linear-energy-transfer (LET)-charged particles through small volumes. If a typical cell nucleus is considered to be about 7 micron, at an exposure rate of 2.5 X 10(-1) C kg-1 h-1 (1 mR hr-1) from a 60Co irradiation, the average cell nucleus receives one energy deposition event every 12.5 d. Biological processes, which modify radiation damage, typically occur in a few minutes to a few hours. Thus, at occupational exposure levels it is probably the irreparable or misrepaired effects of irradiation that determine the biological consequences. One goal of dosimetry is to measure the incident radiation, making it possible to predict biological risk and set meaningful exposure limits. These measurements must relate to the energy depositions that are responsible for radiation effects at low dose rates, yet the dosimetry system must not be excessively complex to allow use by operational health physicists. Furthermore, our description of the irradiation should be directly measurable. The use of quality factors based upon the energy deposition in a 1-micron-diameter volume of tissue as prescribed in International Commission on Radiation Units Report No. 40 (Joint Task Group 1986) satisfies these requirements. Instrumentation based upon measurement of lineal energy has already been successfully used in health-physics applications. Future changes in the quality factor can be accommodated by changing the algorithm in these microprocessor-based instruments.

  5. Stellar kinematic groups. I - The Ursa Major group

    NASA Technical Reports Server (NTRS)

    Soderblom, David R.; Mayor, Michel

    1993-01-01

    The Ursa Major Group (UMaG) is studied as a test case for the authenticity of Stellar Kinematic Groups, using Coravel radial velocities, recent compilations of astrometric data, and new spectroscopic observations. Spectroscopic age indicators, particularly indices of the strength of chromospheric emission, are applied to solar-type candidate members of UMaG, and it is shown that stars that meet the spectroscopic criteria also have kinematics that agree better with the space motions of the nucleus of UMaG than does the starting sample as a whole. The primary limitation on the precision of kinematics is now parallaxes instead of radial velocities. These more restrictive kinematic criteria are then applied to other UMaG candidates and a list summarizing membership is presented. UMaG is also examined as a cluster, confirming its traditional age of 0.3 Gyr, and a mean Fe/H of -0.08 +/- 0.09 for those stars most likely to be bona fide members.

  6. The Minority Group Teacher: An Endangered Species.

    ERIC Educational Resources Information Center

    Tewel, Kenneth J.; Trubowitz, Sidney

    1987-01-01

    Reasons for the decrease in the number of minority group teachers are the following: (1) low status and salaries; (2) alternative career possibilities; (3) desegregation; (4) teacher competency tests; (5) limited career advancement opportunities; and (6) reduction in government supported programs. Recruitment programs, financial incentives, and…

  7. Risk allocation and competition in foraging groups: reversed effects of competition if group size varies under risk of predation.

    PubMed Central

    Bednekoff, Peter A.; Lima, Steven L.

    2004-01-01

    Animals often feed more quickly when in larger groups. This group-size effect is often explained by safety advantages for groups but an alternative explanation is that animals feed faster in larger groups because of greater scramble competition for limited food. We show that predation risk enhances the group-size effect if groups vary in size. By contrast, competition leads to the group-size effect only when individuals feed in groups of constant size. When individuals feed in groups that vary in size, the best strategy for dealing with competition is to feed intensely when in smaller groups and feed little when in larger (more competitive) groups. In all situations, the effects of competition interact with the effects of predation risk in a simple multiplicative way. Our results suggest that scramble competition is not a general explanation for the group-size effect on vigilance in situations where group size changes relatively rapidly. PMID:15306321

  8. Children's Divorce Groups

    ERIC Educational Resources Information Center

    Wilkinson, Gary S.; Bleck, Robert T.

    1977-01-01

    Elementary school counselors can implement a specific strategy to meet the needs of the children of divorce by using many of the techniques already in use. The activities used in the Children's Divorce Groups are ones that have been skillfully developed by counselors familiar with the developmental model of counseling. (Author/PC)

  9. Squeezing and quantum groups

    NASA Astrophysics Data System (ADS)

    Celeghini, E.; Rasetti, M.; Vitiello, G.

    1991-04-01

    Generalized quasicoherent states for the Weyl-Heisenberg quantum group have been defined by Biedenharn and MacFarlane. In this Letter other quantum Weyl-Heisenberg coherent states are defined for complex q in the usual Fock space. Such states are shown to exhibit interesting squeezing properties, in particular when ||q||~=1, for the q analog to the harmonic oscillator.

  10. Group Problem Solving.

    ERIC Educational Resources Information Center

    King, James C.

    1988-01-01

    This pamphlet discusses group problem solving in schools. Its point of departure is that teachers go at problems from a number of different directions and that principals need to capitalize on those differences and bring a whole range of skills and perceptions to the problem-solving process. Rather than trying to get everyone to think alike,…

  11. Assessing Minority Group Children.

    ERIC Educational Resources Information Center

    Phillips, Beeman N., Ed.

    Contents of this book include the following collection of articles: "Assessing Minority Group Children: Challenges for School Psychologists," Thomas Oakland; "The NEA Testing Moratorium," Boyd Bosma; "Cultural Myopia: The Need for a Corrective Lens," Martin H. Gerry; "Assumptions Underlying Psychological Testing," T. Ernest Newland;…

  12. Valuing Support Groups

    ERIC Educational Resources Information Center

    Graziosi, Elena

    2010-01-01

    For people living with or caring for someone with a disability, being able to talk to someone who can relate to their feelings of frustration during difficult times, offer practical advice on an issue, or even understand the importance of a small success, can make a difference. Support groups are a mainstay for individuals coping with daily…

  13. Teaching Badminton to Groups.

    ERIC Educational Resources Information Center

    Nelson, Jonathan E.

    1980-01-01

    Numerous ideas for teaching badminton to large groups are presented. The focus is on drills and techniques for off the court instructional stations. Instead of having students waiting their turn to play, more students can participate actively as they rotate from one station to another. (JN)

  14. Internet Cancer Support Groups

    PubMed Central

    Chee, Wonshik; Tsai, Hsiu-Min; Lin, Li-Chen; Cheng, Ching-Yu

    2006-01-01

    Internet Cancer Support Groups (ICSGs) are an emerging form of support group on Internet specifically for cancer patients. Previous studies have indicated the effectiveness of ICSGs as a research setting or a data-collection method. Yet recent studies have also indicated that ICSGs tend to serve highly educated, high-income White males who tend to be at an early stage of cancer. In this article, a total of 317 general ICSGs and 229 ethnic-specific ICSGs searched through Google.com, Yahoo.com, http://Msn.com, AOL.com, and ACOR.org are analyzed from a feminist perspective. The written records of group discussions and written memos by the research staff members were also analyzed using content analysis. The idea categories that emerged about these groups include (a) authenticity issues; (b) ethnicity and gender issues; (c) intersubjectivity issues; and (d) potential ethical issues. The findings suggest that (a) researchers adopt multiple recruitment strategies through various Internet sites and/or real settings; (b) researchers raise their own awareness of the potential influences of the health-related resources provided by ICSGs and regularly update their knowledge related to the federal and state standards and/or policies related to ICSGs; and (c) researchers consider adopting a quota-sampling method. PMID:15681976

  15. Abandoning wells working group

    SciTech Connect

    1997-03-01

    The primary objective of this working group is to identify major technical, regulatory, and environmental issues that are relevant to the abandonment of offshore wellbores. Once the issues have been identified, the working group also has the objective of making recommendations or providing potential solutions for consideration. Areas for process improvement will be identified and {open_quotes}best practices{close_quotes} will be discussed and compared to {open_quotes}minimum standards.{close_quotes} The working group will primarily focus on wellbore abandonment in the Gulf of Mexico. However, workshop participants are encouraged to discuss international issues which may be relevant to wellbore abandonment practices in the Gulf of Mexico. The Abandoning Wells Group has identified several major areas for discussion that have concerns related to both operators and service companies performing wellbore abandonments in the Gulf of Mexico. The following broad topics were selected for the agenda: (1) MMS minimum requirements and state regulations. (2) Co-existence of best practices, new technology, and P & A economics. (3) Liability and environmental issues relating to wellbore abandonment.

  16. Tennis: Group Instruction.

    ERIC Educational Resources Information Center

    United States Lawn Tennis Association, New York, NY.

    This manual is a guide to group instruction of basic tennis. Chapter 1 discusses four premises. Chapter 2 illustrates basic strokes, including the forehand and backhand ground strokes, the forehand and backhand volleys, the lob and overhead smash, and the half-volley. Chapter 3 presents methods of teaching the strokes, some corrective techniques,…

  17. Special Interest Groups.

    ERIC Educational Resources Information Center

    Degi, Bruce J.

    1999-01-01

    Offers a reflection on the shootings at Columbine High School in Littleton, Colorado, on April 20, 1999. Notes how every special-interest group has used the tragedy to support its own point of view, and concludes that teachers have become bystanders in the education of America's children. (SR)

  18. Learning from Nurture Groups

    ERIC Educational Resources Information Center

    Cooper, Paul

    2004-01-01

    This paper deals with Nurture Groups, which are a specialist form of provision for pupils with social, emotional and learning difficulties. The paper outlines the theoretical underpinnings of the NG approach and describes the practical arrangements and operations features of this form of provision. Evidence from research studies exploring the…

  19. International Study Tour Groups

    ERIC Educational Resources Information Center

    O'Reilly, Frances L.; Matt, John J.; McCaw, William P.; Kero, Patty; Stewart, Courtney; Haddouch, Reda

    2014-01-01

    Using the context of international study tour groups, this study examined the personal and professional transformation that occurred among host faculty and staff at The University of Montana-Missoula as a result of their interactions with traveling academics from other countries. Data were collected from participant responses (n = 27) using a…

  20. The Pressure Group Cooker.

    ERIC Educational Resources Information Center

    Graves, Bill

    1992-01-01

    Administrators across the nation have encountered vigorous challenges against textbooks, practices, and procedures that critics find laden with occult and New Age values. Attacks are becoming more aggressive, better organized, and well financed. This article and accompanying sidebars discuss pressure group tactics and ways to counter them. The…

  1. Functional Group Analysis.

    ERIC Educational Resources Information Center

    Smith, Walter T., Jr.; Patterson, John M.

    1984-01-01

    Literature on analytical methods related to the functional groups of 17 chemical compounds is reviewed. These compounds include acids, acid azides, alcohols, aldehydes, ketones, amino acids, aromatic hydrocarbons, carbodiimides, carbohydrates, ethers, nitro compounds, nitrosamines, organometallic compounds, peroxides, phenols, silicon compounds,…

  2. Working With Citizens' Groups

    ERIC Educational Resources Information Center

    Sullivan, James B.

    1974-01-01

    The growing demand for expert technical advice in the areas of environmental impact statements, testimony at public hearings, and testimony in consumer or environmental litigation is examined. Brief descriptions of thirteen of the most active public-interest science groups are included. (DT)

  3. Group Counseling: Health Related.

    ERIC Educational Resources Information Center

    McFadden, Johnnie

    1979-01-01

    Diabetes and sickle cell anemia (SCA) are two health-related characteristics that distinguish young people from their peers. This article outlines the problems of children with diabetes and SCA and presents the goals and format for group counseling of these populations and their parents. (Author/BEF)

  4. National Melon Research Group

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The National Melon Research Group met with the Cucurbitaceae 2010 conference in Charleston, South Carolina at 7:00 P.M. on November 17. The discussion was focused solely on cucurbit powdery mildew (CPM). Several reported increased problem with CPM or apparent changes in race. Ales Lebeda (Palacký Un...

  5. Project Echo Task Group

    NASA Technical Reports Server (NTRS)

    1964-01-01

    'A technician assigned to the Project Echo Task Group separates the two hemispheres of the Echo 1 container for inspection. The charge that freed the balloon was placed inside of a ring encircling the canister at its equator.' Published in James R. Hansen, Spaceflight Revolution: NASA Langley Research Center From Sputnik to Apollo, NASA SP-4308, p. 181.

  6. [Transference and group psychotherapy].

    PubMed

    Bechelli, Luiz Paulo de C; Santos, Manoel Antônio Dos

    2006-01-01

    This study examines the concept of transference, focusing on its peculiarities in the group context. The nature of the therapeutic situation and the broad freedom given to patients in order to access the unconscious material at their own pace, within a safe environment and with as little censorship as can be managed, transference gradually takes place. Through displacement, the psychotherapist and group members are perceived not as they are, with their real attributes, but as one or more objects that arouse emotions coming from the infant world, more precisely from the collection of deep affective influences. One peculiarity of the group situation when compared to individual psychotherapy is that, in the former, multiple transferences coexist, which group members establish among themselves, enabling a wide range of possible feelings. Both treatment modes share the assumption that unresolved conflicts which stimulated patients to seek for help can be reduced or even abolished through the interpretation and working through of transference, which functions as a process of change throughout the psychotherapy. PMID:16532247

  7. Native American Cultural Groups.

    ERIC Educational Resources Information Center

    Roy, Loriene, Comp.

    Part of a larger report on the Four Directions Project, an American Indian technology innovation project, this section includes 13 "pathfinders" to locating information on Native American and other indigenous cultural groups. The pathfinders were designed by students in the Graduate School of Library and Information Science at the University of…

  8. Group Home Management.

    ERIC Educational Resources Information Center

    Little (Arthur D.), Inc., Washington, DC.

    This guide seeks improvement in group home management, especially community-based residential facilities for juvenile offenders. Primary organizational considerations include structure, communication lines and decision making. The role of the Board of Directors is explored from initial selection through definition of the program directors role.…

  9. Belonging to the Group.

    ERIC Educational Resources Information Center

    Perry, Bruce D.

    2002-01-01

    Describes how teachers can help children feel included, connected, and valued, explaining that the family is the child's first and most important group, and children learn the rules of social interaction from primary relationships with adults. As children play, they learn and formulate their own social rules. Teachers can provide structured,…

  10. Leukosis/Sarcoma Group

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The leukosis/sarcoma (L/S) group of diseases designates a variety of transmissible benign and malignant neoplasms of chickens caused by members that belong to the family Retroviridae. Because the expansion of the literature on this disease, it is no longer feasible to cite all relevant publications ...

  11. LCDs Revolutionize Group Training.

    ERIC Educational Resources Information Center

    Mandell, Mel

    1987-01-01

    Describes a screen projector based on liquid crystal display (LCD) that duplicates the monitor of a microcomputer and may be used in group training sessions for demonstration purposes. Suggestions of what features to look for and a buyer's guide are provided. (CLB)

  12. Losing the safety net: how a time-limited welfare policy affects families at risk of reaching time limits.

    PubMed

    Morris, Pamela A; Hendra, Richard

    2009-03-01

    The authors examined the effects of Florida's Family Transition Program (FTP), one of the first welfare reform initiatives to include a time limit on the receipt of federal cash assistance with other welfare requirements, on single-mother welfare-receiving families. Using a regression-based subgroup approach, they identified a group of families who were at risk of reaching the welfare time limit and subsequently assessed the experimental effects of the time-limited welfare policy on this group as compared to an otherwise comparable group of single-mother welfare-recipient families. For the families who were at risk of reaching the welfare time limit, FTP had few effects. FTP decreased mothers' depressive symptoms, and mothers in the FTP group reported higher levels of children's school achievement. There were no effects on parenting behavior or mothers' reports of children's social-emotional outcomes.

  13. Mixed Waste Working Group report

    SciTech Connect

    Not Available

    1993-11-09

    The treatment of mixed waste remains one of this country`s most vexing environmental problems. Mixed waste is the combination of radioactive waste and hazardous waste, as defined by the Resource Conservation and Recovery Act (RCRA). The Department of Energy (DOE), as the country`s largest mixed waste generator, responsible for 95 percent of the Nation`s mixed waste volume, is now required to address a strict set of milestones under the Federal Facility Compliance Act of 1992. DOE`s earlier failure to adequately address the storage and treatment issues associated with mixed waste has led to a significant backlog of temporarily stored waste, significant quantities of buried waste, limited permanent disposal options, and inadequate treatment solutions. Between May and November of 1993, the Mixed Waste Working Group brought together stakeholders from around the Nation. Scientists, citizens, entrepreneurs, and bureaucrats convened in a series of forums to chart a course for accelerated testing of innovative mixed waste technologies. For the first time, a wide range of stakeholders were asked to examine new technologies that, if given the chance to be tested and evaluated, offer the prospect for better, safer, cheaper, and faster solutions to the mixed waste problem. In a matter of months, the Working Group has managed to bridge a gap between science and perception, engineer and citizen, and has developed a shared program for testing new technologies.

  14. Broad-host-range plasmids in treated wastewater effluent and receiving streams.

    PubMed

    Akiyama, Tatsuya; Asfahl, Kyle L; Savin, Mary C

    2010-01-01

    The occurrence of broad-host-range (BHR) plasmid amplicons belonging to incompatibility (Inc) groups IncA/C, IncN, IncP, and IncW in two wastewater treatment plant (WWTP) effluents and effluent-receiving streams in Northwest Arkansas, Mud Creek and Spring Creek, was determined. Community DNA captured on filter membranes and plasmid DNA extracted from antibiotic-resistant Escherichia coli isolated from Mud Creek was used for polymerase chain reaction at amplification of partial gene sequences specific to BHR plasmids. IncP plasmid amplicons were detected in effluent and downstream sites in both streams, while IncN and IncW plasmid amplicons were detected in Spring Creek in effluent and downstream but not upstream. IncA/C plasmid amplicons, in contrast, were detected at all sites, including upstream in most samples in Spring Creek and in one sample from Mud Creek. One IncP and two IncN were the only BHR plasmid amplicons found in 85 screened antibiotic-resistant E. coli isolates, and were detected only in isolates from effluent and downstream samples. Broad-host-range plasmids frequently carry antibiotic-resistance genes and can facilitate horizontal transfer of those genes. While BHR plasmids have been detected in WWTPs, WWTPs do not target these genetic elements for destruction. This study indicates that BHR plasmids are in WWTP effluent and are introducing BHR plasmids into streams. Additionally, species other than E. coli may be better targets as indicator bacteria for future studies of the impact of treated effluent on environmental dissemination of BHR plasmids.

  15. Modification of the platelet binding domain of von Willebrand Factor (vWF)

    SciTech Connect

    Silverman, C.; Mascelli, M.A.; Karl, D.W.; Kirby, E.P.

    1986-05-01

    Bovine vWF has been modified with /sup 125/I-Bolton Hunter reagent (I/sup */-BHR) with a concomittant loss of its platelet agglutinating activity and a reduction in its ability to bind to platelets. BHR labels free alpha and epsilon amino groups. The I/sup */-BHR-vWF migrated as a single band of M/sub r/ = 210kD on reduced SDS polyacrylamide gels. Its multimeric composition on SDS agarose gels was identical to unlabeled vWF. Incorporation of an average of 1.2 moles of I/sup */-BHR/subunit vWF at pH 8.5 caused a 50% loss of platelet agglutinating activity. This represents less than 2% of the 118 lysine residues in each subunit vWF. No I/sup */-BHR was released after treatment with 1M hydroxylamine which would cleave O-acylated tyrosines. Digestion of both unlabeled and I/sup */-BHR-vWF with Protease 1, a metalloprotease from the venom of western diamondback rattlesnake, produces two fragments which have an M/sub r/ of 250kD and 200kD. The 250kD fragment contains the platelet binding site and is composed of 3 peptide chains with M/sub r/ 125kD, 78kD and 45kD. Gels of the 250kD fragment from I/sup */-BHR-vWF revealed radioactivity predominantly in the 125kD fragment, suggesting that the platelet binding site resides on the 125kD fragment.

  16. A cryogenically coolable microwave limiter

    PubMed

    Rinard; Quine; Eaton

    1999-02-01

    A microwave (ca. 3 GHz) limiter, constructed using a GaAs PIN diode and microstrip impedance transformation circuit, limited 300-ns long 11-W microwave pulses to 70 mW at ca. 4.2 K. This limiter was implemented in a pulsed electron paramagnetic resonance (EPR) spectrometer to protect a low-noise microwave preamplifier from the high-power pulses. Copyright 1999 Academic Press. PMID:9986762

  17. Group Work with the Elderly: An Overview for Counselors.

    ERIC Educational Resources Information Center

    Capuzzi, Dave; Gross, Doug

    1980-01-01

    Loneliness and isolation of older adults can be treated with group therapy. Group methods such as reality orientation, remotivation, reminiscing and psychotherapy groups can increase social interaction but require special consideration of environment, scheduling and individual limitation as well as counselor training. (JAC)

  18. Interpersonal Perception in Group Therapy: A Social Relations Analysis.

    ERIC Educational Resources Information Center

    Marcus, David K.; Holahan, William

    1994-01-01

    Describes investigation in which participants in time-limited group therapy reported impressions of fellow group members via Impact Message Inventory. Social relations analysis of data indicated that subjects' perceptions included both assimilation and consensus. Suggests results demonstrate utility of social relations model for group therapy…

  19. Regrouping Groups: A Reaction to Waldo and Bauman.

    ERIC Educational Resources Information Center

    Ward, Donald E.

    1998-01-01

    The development of the Association for Specialists in Group Work's (ASGW) four-category system for classifying types of group work is described. Strengths and limitations of the Waldo and Bauman proposed Goals and Process (GAP) matrix for group work categorization are identified and discussed in relation to the present ASGW system. (Author/MKA)

  20. Limitations in thermal scale modeling

    NASA Technical Reports Server (NTRS)

    Macgregor, R. K.

    1971-01-01

    Thermal scale modeling limitations for radiation- conduction system of unmanned spacecraft, discussing material thermal properties, model dimensions, instrumentation effects and environment simulation

  1. Experimental studies on pump limiters

    NASA Astrophysics Data System (ADS)

    Mioduszewski, P.

    1982-12-01

    Pump limiters are mechanical devices for He-ash removal, fuel particle control, and possibly impurity control. Different designs have been suggested by various authors over the past decade. However, the magnetic divertor concepts seemed to be more promising, mainly because of their remote plasma-material interactions. All of the characteristics of magnetic divertors have been proven experimentally, but the overall performance and complexity cause concern about their application to tokamak reactors. Consequently, it is now time to explore the potential of mechanical particle control devices, i.e. pump limiters. Because of the high recycling at the limiter, it is sufficient to exhaust only a small fraction, about 1-10%, of the limiter particle flux to remove e.g. He at its rate of production. Pump limiter experiments have been conducted so far on Alcator, PDX, Macrotor, and ISX. Depending on the experimental design, a pressure build-up of between 1 mTorr and 50 mTorr has been reported. The closed configuration pump limiters provide high collection efficiencies, but have to accomodate high power fluxes at the leading edge. An open configuration, on the other hand, avoids leading edges but provides only fairly low collection efficiencies. The pump limiter development program now calls for a full pump limiter to be implemented in a major tokamak device. Presently, full-size pump limiter experiments on PDX, ISX, and TEXTOR are in preparation.

  2. Group Formation in Economics

    NASA Astrophysics Data System (ADS)

    Demange, Gabrielle; Wooders, Myrna

    2005-01-01

    Broad and diverse ranges of activities are conducted within and by organized groups of individuals, including political, economic and social activities. These activities have recently become a subject of intense interest in economics and game theory. Some of the topics investigated in this collection are models of networks of power and privilege, trade networks, co-authorship networks, buyer-seller networks with differentiated products, and networks of medical innovation and the adaptation of new information. Other topics are social norms on punctuality, clubs and the provision of club goods and public goods, research and development and collusive alliances among corporations, and international alliances and trading agreements. While relatively recent, the literature on game theoretic studies of group formation in economics is already vast. This volume provides an introduction to this important literature on game-theoretic treatments of situations with networks, clubs, and coalitions, including some applications.

  3. KKG Group Paraffin Removal

    SciTech Connect

    Schulte, Ralph

    2001-12-01

    The Rocky Mountain Oilfield Testing Center (RMOTC) has recently completed a test of a paraffin removal system developed by the KKG Group utilizing the technology of two Russian scientists, Gennady Katzyn and Boris Koggi. The system consisting of chemical ''sticks'' that generate heat in-situ to melt the paraffin deposits in oilfield tubing. The melted paraffin is then brought to the surface utilizing the naturally flowing energy of the well.

  4. Hadron hadron collider group

    SciTech Connect

    Palmer, R.; Peoples, J.; Ankenbrandt, C.

    1982-01-01

    The objective of this group was to make a rough assessment of the characteristics of a hadron-hadron collider which could make it possible to study the 1 TeV mass scale. Since there is very little theoretical guidance for the type of experimental measurements which could illuminate this mass scale, we chose to extend the types of experiments which have been done at the ISR, and which are in progress at the SPS collider to these higher energies.

  5. Functional group analysis

    SciTech Connect

    Smith, W.T. Jr.; Patterson, J.M.

    1986-04-01

    Analytical methods for functional group analysis are reviewed. Literature reviewed is from the period of December 1983 through November 1985 and presents methods for determining the following compounds: acids, acid halides, active hydrogen, alcohols, aldehydes, ketones, amides, amines, amino acids, anhydrides, aromatic hydrocarbons, azo compounds, carbohydrates, chloramines, esters, ethers, halogen compounds, hydrazines, isothiocyanates, nitro compounds, nitroso compounds, organometallic compounds, oxiranes, peroxides, phenols, phosphorus compounds, quinones, silicon compounds, sulfates, sulfonyl chlorides, thioamides, thiols, and thiosemicarbazones. 150 references.

  6. Summaries of group discussions

    NASA Technical Reports Server (NTRS)

    Jensen, L. D.

    1972-01-01

    Group discussions following the presentations of reports on the remote sensing of Chesapeake Bay resources are presented. The parameters to be investigated by the remote sensors and the specifications of the sensors are described. Specific sensors for obtaining data on various aspects of the ecology are identified. Recommendations for establishing a data bank and additional efforts to obtain increased understanding of the ecology are submitted.

  7. The Effects of Group Members' Personalities on a Test Taker's L2 Group Oral Discussion Test Scores

    ERIC Educational Resources Information Center

    Ockey, Gary J.

    2009-01-01

    The second language group oral is a test of second language speaking proficiency, in which a group of three or more English language learners discuss an assigned topic without interaction with interlocutors. Concerns expressed about the extent to which test takers' personal characteristics affect the scores of others in the group have limited its…

  8. Operational slope-limiting circuit

    NASA Technical Reports Server (NTRS)

    Engel, A.

    1973-01-01

    Circuit limits slope of arbitrary waveform to avoid exceeding rate limit of subsequent amplifier, or to form trapezoidal wave with adjustable rise and fall rates from square wave of arbitrary frequency. Integrator provides delay needed to develop output waveform. DC coupling is used to preserve original dc offset.

  9. Solubility limits on radionuclide dissolution

    SciTech Connect

    Kerrisk, J.F.

    1984-12-31

    This paper examines the effects of solubility in limiting dissolution rates of a number of important radionuclides from spent fuel and high-level waste. Two simple dissolution models were used for calculations that would be characteristics of a Yucca Mountain repository. A saturation-limited dissolution model, in which the water flowing through the repository is assumed to be saturated with each waste element, is very conservative in that it overestimates dissolution rates. A diffusion-limited dissolution model, in which element-dissolution rates are limited by diffusion of waste elements into water flowing past the waste, is more realistic, but it is subject to some uncertainty at this time. Dissolution rates of some elements (Pu, Am, Sn, Th, Zr, Sm) are always limited by solubility. Dissolution rates of other elements (Cs, Tc, Np, Sr, C, I) are never solubility limited; their release would be limited by dissolution of the bulk waste form. Still other elements (U, Cm, Ni, Ra) show solubility-limited dissolution under some conditions. 9 references, 3 tables.

  10. Delving into Limits of Sequences

    ERIC Educational Resources Information Center

    Cory, Beth; Smith, Ken W.

    2011-01-01

    Limits are foundational to the central concepts of calculus. However, the authors' experiences with students and educational research abound with examples of students' misconceptions about limits and infinity. The authors wanted calculus students to understand, appreciate, and enjoy their first introduction to advanced mathematical thought. Thus,…

  11. FUEL CASK IMPACT LIMITER VULNERABILITIES

    SciTech Connect

    Leduc, D; Jeffery England, J; Roy Rothermel, R

    2009-02-09

    Cylindrical fuel casks often have impact limiters surrounding just the ends of the cask shaft in a typical 'dumbbell' arrangement. The primary purpose of these impact limiters is to absorb energy to reduce loads on the cask structure during impacts associated with a severe accident. Impact limiters are also credited in many packages with protecting closure seals and maintaining lower peak temperatures during fire events. For this credit to be taken in safety analyses, the impact limiter attachment system must be shown to retain the impact limiter following Normal Conditions of Transport (NCT) and Hypothetical Accident Conditions (HAC) impacts. Large casks are often certified by analysis only because of the costs associated with testing. Therefore, some cask impact limiter attachment systems have not been tested in real impacts. A recent structural analysis of the T-3 Spent Fuel Containment Cask found problems with the design of the impact limiter attachment system. Assumptions in the original Safety Analysis for Packaging (SARP) concerning the loading in the attachment bolts were found to be inaccurate in certain drop orientations. This paper documents the lessons learned and their applicability to impact limiter attachment system designs.

  12. The limits of crop productivity

    NASA Technical Reports Server (NTRS)

    Bugbee, Bruce; Monje, Oscar

    1992-01-01

    The component processes that govern yield limits in food crops are reviewed and how each process can be individually measured is described. The processes considered include absorption of photosynthetic radiation by green tissue, carbon-fixation efficiency in photosynthesis, carbon use efficiency in respiration, biomass allocation to edible products, and efficiency of photosynthesis and respiration. The factors limiting yields in optimal environments are considered.

  13. Time Limits and Welfare Use

    ERIC Educational Resources Information Center

    Grogger, Jeffrey

    2004-01-01

    Time limits represent a substantial departure from previous welfare policy. Theory suggests that their effects should vary according to the age of the youngest child of the family. I test this prediction using data from the Current Population Survey and find that time limits indeed have larger effects on families with younger children. I further…

  14. Limits to magnetic resonance microscopy

    NASA Astrophysics Data System (ADS)

    Glover, Paul; Mansfield, Peter, Sir

    2002-10-01

    The last quarter of the twentieth century saw the development of magnetic resonance imaging (MRI) grow from a laboratory demonstration to a multi-billion dollar worldwide industry. There is a clinical body scanner in almost every hospital of the developed nations. The field of magnetic resonance microscopy (MRM), after mostly being abandoned by researchers in the first decade of MRI, has become an established branch of the science. This paper reviews the development of MRM over the last decade with an emphasis on the current state of the art. The fundamental principles of imaging and signal detection are examined to determine the physical principles which limit the available resolution. The limits are discussed with reference to liquid, solid and gas phase microscopy. In each area, the novel approaches employed by researchers to push back the limits of resolution are discussed. Although the limits to resolution are well known, the developments and applications of MRM have not reached their limit.

  15. Force Limited Vibration Testing Monograph

    NASA Technical Reports Server (NTRS)

    Scharton, Terry D.

    1997-01-01

    The practice of limiting the shaker force in vibration tests was investigated at the NASA Jet Propulsion Laboratory (JPL) in 1990 after the mechanical failure of an aerospace component during a vibration test. Now force limiting is used in almost every major vibration test at JPL and in many vibration tests at NASA Goddard Space Flight Center (GSFC) and at many aerospace contractors. The basic ideas behind force limiting have been in the literature for several decades, but the piezo-electric force transducers necessary to conveniently implement force limiting have been available only in the last decade. In 1993, funding was obtained from the NASA headquarters Office of Chief Engineer to develop and document the technology needed to establish force limited vibration testing as a standard approach available to all NASA centers and aerospace contractors. This monograph is the final report on that effort and discusses the history, theory, and applications of the method in some detail.

  16. Applications of Quantum Groups

    NASA Astrophysics Data System (ADS)

    Chryssomalakos, Chryssomalis

    The main theme of this thesis is the search for applications of Quantum Group and Hopf algebraic concepts and techniques in Physics. We investigate in particular the possibilities that exist in deforming, in a self consistent way, the symmetry structure of physical theories with the hope that the resulting scheme will be of relevance in the description of physical reality. Our choice of topics reflects this motivation: we discuss deformations of rotations and Lorentz boosts, search for integrals on the quantum plane and attempt to Fourier transform functions of non -commuting coordinates. Along the way, more formal considerations prompt us to revisit integration on finite dimensional Hopf algebras, explore the interconnections between various descriptions of the quantum double and derive the algebraic structure of the quantum plane from that of the underlying deformed symmetry group. The material is structured as follows. Chapter 1 introduces the language, basic concepts and notation employed throughout this thesis. Chapter 2 focuses on Hopf algebras viewed as universal envelopes of deformed Lie algebras and their duals. Bicovariant generators enter the discussion as analogues of the classical Lie algebra generators and some of their properties are given. We comment on the geometrical interpretation of the algebraic formulation and introduce computational tools. In chapter 3 we take a close look at the quantum Lorentz Hopf algebra. The basics of complex quantum groups are presented and applied in the derivation of the algebra of the quantum Lorentz generators and its Hopf and involutive structures. We point also to isomorphisms with previous related constructions. The subject of quantum integration is explored in chapter 4. We derive a formula for the integral on a finite dimensional Hopf algebra and show its equivalence to the formulation in terms of the trace of the square of the antipode. Integration on the quantum plane is also examined and a Fourier transform

  17. Systems special investigation group

    NASA Technical Reports Server (NTRS)

    1991-01-01

    An interim report concerning the Long Duration Exposure Facility (LDEF) is presented by a Boeing Systems special investigation group (SIG). The SIG activities were divided into five engineering disciplines: electrical, mechanical, optics, thermal, and batteries/solar cells. The responsibilities of the SIG included the following areas: support de-integration at Kennedy Space Center (KSC); testing of hardware at Boeing; review of principal investigator (PI) test plans and test results; support of test activities at PI labs; and collation of all test results into the SIG database.

  18. Theory and modeling group

    NASA Technical Reports Server (NTRS)

    Holman, Gordon D.

    1989-01-01

    The primary purpose of the Theory and Modeling Group meeting was to identify scientists engaged or interested in theoretical work pertinent to the Max '91 program, and to encourage theorists to pursue modeling which is directly relevant to data which can be expected to result from the program. A list of participants and their institutions is presented. Two solar flare paradigms were discussed during the meeting -- the importance of magnetic reconnection in flares and the applicability of numerical simulation results to solar flare studies.

  19. STEAM GENERATOR GROUP PROJECT

    SciTech Connect

    Clark, R. A.; Lewis, M

    1985-09-01

    This report is a summary of progress in the Surry Steam Generator Group Project for 1984. Information is presented on the analysis of two baseline eddy current inspections of the generator. Round robin series of tests using standard in-service inspection techniques are described along with some preliminary results. Observations are reported of degradation found on tubing specimens removed from the generator, and on support plates characterized in-situ. Residual stresses measured on a tubing specimen are reported. Two steam generator repair demonstrations are described; one for antivibration bar replacement, and one on tube repair methods. Chemical analyses are shown for sludge samples removed from above the tube sheet.

  20. Renormalization group functional equations

    SciTech Connect

    Curtright, Thomas L.; Zachos, Cosmas K.

    2011-03-15

    Functional conjugation methods are used to analyze the global structure of various renormalization group trajectories and to gain insight into the interplay between continuous and discrete rescaling. With minimal assumptions, the methods produce continuous flows from step-scaling {sigma} functions and lead to exact functional relations for the local flow {beta} functions, whose solutions may have novel, exotic features, including multiple branches. As a result, fixed points of {sigma} are sometimes not true fixed points under continuous changes in scale and zeroes of {beta} do not necessarily signal fixed points of the flow but instead may only indicate turning points of the trajectories.

  1. Tate form and weak coupling limits in F-theory

    NASA Astrophysics Data System (ADS)

    Esole, Mboyo; Savelli, Raffaele

    2013-06-01

    We consider the weak coupling limit of F-theory in the presence of non-Abelian gauge groups implemented using the traditional ansatz coming from Tate's algorithm. We classify the types of singularities that could appear in the weak coupling limit and explain their resolution. In particular, the weak coupling limit of SU( n) gauge groups leads to an orientifold theory which suffers from conifold singulaties that do not admit a crepant resolution compatible with the orientifold involution. We present a simple resolution to this problem by introducing a new weak coupling regime that admits singularities compatible with both a crepant resolution and an orientifold symmetry. We also comment on possible applications of the new limit to model building. We finally discuss other unexpected phenomena as for example the existence of several non-equivalent directions to flow from strong to weak coupling leading to different gauge groups.

  2. Multimedia group communications: towards new services

    NASA Astrophysics Data System (ADS)

    Mauthe, A.; Hutchison, D.; Coulson, G.; Namuye, S.

    1996-09-01

    Interpersonal communication among a group of users employing different media types is becoming more and more widespread in computing and telecommunications. Group communication places a variety of new requirements onto the underlying communications architecture and although many existing protocols and services do offer some limited support for multicast group communication, these new requirements make it difficult to find efficient and comprehensive solutions. The impact of multimedia group communication on the communication system and the way in which existing systems, international standardization bodies and researchers cope with these challenges is the subject of this paper. First the characteristics and requirements of multimedia group applications are discussed and illustrated by examples of existing group applications. Subsequently a survey of the kind of support available in today's communication system is presented. In addition the ongoing discussion about the standardization of group communication within ISO and ITU and the direction these efforts take is briefly summarized. Further, some selected examples of research projects which deal with different communication and protocol related aspects of multimedia group communication are presented which give an indication of the trends in this area.

  3. Group Processes in Experiential Training Groups in Botswana

    ERIC Educational Resources Information Center

    Nitza, Amy

    2011-01-01

    While group counseling has the potential to be an effective form of intervention in sub-Saharan Africa, research on group processes that would help guide group interventions in the region is scarce. This study investigated therapeutic factors and group climate in experiential training groups in Botswana. The Critical Incident Questionnaire (CIQ;…

  4. Group Progress of Community Elderly as Measured by Tape Recordings, Group Tempo and Group Evaluation.

    ERIC Educational Resources Information Center

    Weiner, Marcella Bakur; Weinstock, Comilda S.

    1979-01-01

    Geriatric outpatients were involved in a group resocialization program. Comparison is made between experimental groups whose leader used group intervention techniques, and groups where leader played a nonintervention role. Experimental group members showed changes toward more active problem-solving approaches, while group members remained fixed at…

  5. Group size, grooming and fission in primates: a modeling approach based on group structure.

    PubMed

    Sueur, Cédric; Deneubourg, Jean-Louis; Petit, Odile; Couzin, Iain D

    2011-03-21

    In social animals, fission is a common mode of group proliferation and dispersion and may be affected by genetic or other social factors. Sociality implies preserving relationships between group members. An increase in group size and/or in competition for food within the group can result in decrease certain social interactions between members, and the group may split irreversibly as a consequence. One individual may try to maintain bonds with a maximum of group members in order to keep group cohesion, i.e. proximity and stable relationships. However, this strategy needs time and time is often limited. In addition, previous studies have shown that whatever the group size, an individual interacts only with certain grooming partners. There, we develop a computational model to assess how dynamics of group cohesion are related to group size and to the structure of grooming relationships. Groups' sizes after simulated fission are compared to observed sizes of 40 groups of primates. Results showed that the relationship between grooming time and group size is dependent on how each individual attributes grooming time to its social partners, i.e. grooming a few number of preferred partners or grooming equally or not all partners. The number of partners seemed to be more important for the group cohesion than the grooming time itself. This structural constraint has important consequences on group sociality, as it gives the possibility of competition for grooming partners, attraction for high-ranking individuals as found in primates' groups. It could, however, also have implications when considering the cognitive capacities of primates.

  6. Violent extremist group ecologies under stress.

    PubMed

    Cebrian, Manuel; Torres, Manuel R; Huerta, Ramon; Fowler, James H

    2013-01-01

    Violent extremist groups are currently making intensive use of Internet fora for recruitment to terrorism. These fora are under constant scrutiny by security agencies, private vigilante groups, and hackers, who sometimes shut them down with cybernetic attacks. However, there is a lack of experimental and formal understanding of the recruitment dynamics of online extremist fora and the effect of strategies to control them. Here, we utilize data on ten extremist fora that we collected for four years to develop a data-driven mathematical model that is the first attempt to measure whether (and how) these external attacks induce extremist fora to self-regulate. The results suggest that an increase in the number of groups targeted for attack causes an exponential increase in the cost of enforcement and an exponential decrease in its effectiveness. Thus, a policy to occasionally attack large groups can be very efficient for limiting violent output from these fora.

  7. Violent extremist group ecologies under stress

    PubMed Central

    Cebrian, Manuel; Torres, Manuel R.; Huerta, Ramon; Fowler, James H.

    2013-01-01

    Violent extremist groups are currently making intensive use of Internet fora for recruitment to terrorism. These fora are under constant scrutiny by security agencies, private vigilante groups, and hackers, who sometimes shut them down with cybernetic attacks. However, there is a lack of experimental and formal understanding of the recruitment dynamics of online extremist fora and the effect of strategies to control them. Here, we utilize data on ten extremist fora that we collected for four years to develop a data-driven mathematical model that is the first attempt to measure whether (and how) these external attacks induce extremist fora to self-regulate. The results suggest that an increase in the number of groups targeted for attack causes an exponential increase in the cost of enforcement and an exponential decrease in its effectiveness. Thus, a policy to occasionally attack large groups can be very efficient for limiting violent output from these fora. PMID:23536118

  8. Geographic range limits: achieving synthesis

    PubMed Central

    Gaston, Kevin J.

    2009-01-01

    Understanding of the determinants of species' geographic range limits remains poorly integrated. In part, this is because of the diversity of perspectives on the issue, and because empirical studies have lagged substantially behind developments in theory. Here, I provide a broad overview, drawing together many of the disparate threads, considering, in turn, how influences on the terms of a simple single-population equation can determine range limits. There is theoretical and empirical evidence for systematic changes towards range limits under some circumstances in each of the demographic parameters. However, under other circumstances, no such changes may take place in particular parameters, or they may occur in a different direction, with limitation still occurring. This suggests that (i) little about range limitation can categorically be inferred from many empirical studies, which document change in only one demographic parameter, (ii) there is a need for studies that document variation in all of the parameters, and (iii) in agreement with theoretical evidence that range limits can be formed in the presence or absence of hard boundaries, environmental gradients or biotic interactions, there may be few general patterns as to the determinants of these limits, with most claimed generalities at least having many exceptions. PMID:19324809

  9. Cardiorespiratory fitness, obesity, and functional limitation in older adults.

    PubMed

    Bouchard, Danielle R; McGuire, K Ashlee; Davidson, Lance; Ross, Robert

    2011-10-01

    One hundred forty-six abdominally obese adults age 60-80 yr were studied to investigate the interaction between cardiorespiratory fitness (CRF) and obesity on functional limitation. Obesity was determined by fat mass (FM), CRF was determined by a maximal treadmill test, and functional limitation was based on 4 different tasks that are predictive of subsequent disability. Both FM (r = -.34, p ≤ .01) and CRF (r = .54, p ≤ .01) were independently associated with functional limitation in bivariate analysis.After further control for sex, age, and the interaction term (CRF × FM), FM was no longer independently associated with functional limitation (p = .10). Analyses were also based on sex-specific tertiles of FM and CRF. The referent group demonstrated significantly lower functional limitation than the low-CRF/low-FM and the low-CRF/high-FM groups (both p ≤ .05). These results highlight the value of recommending exercise for abdominally obese adults.

  10. Central limit theorems under special relativity

    PubMed Central

    McKeague, Ian W.

    2015-01-01

    Several relativistic extensions of the Maxwell–Boltzmann distribution have been proposed, but they do not explain observed lognormal tail-behavior in the flux distribution of various astrophysical sources. Motivated by this question, extensions of classical central limit theorems are developed under the conditions of special relativity. The results are related to CLTs on locally compact Lie groups developed by Wehn, Stroock and Varadhan, but in this special case the asymptotic distribution has an explicit form that is readily seen to exhibit lognormal tail behavior. PMID:25798020

  11. Limit laws for Zipf's law

    NASA Astrophysics Data System (ADS)

    Eliazar, Iddo

    2011-01-01

    In this communication we establish stochastic limit laws leading from Zipf's law to Pareto's and Heaps' laws. We consider finite ensembles governed by Zipf's law and study their asymptotic statistics as the ensemble size tends to infinity. A Lorenz-curve analysis establishes three types of limit laws for the ensembles' statistical structure: 'communist', 'monarchic', and Paretian. Further considering a dynamic setting in which the ensembles grow stochastically in time, a functional central limit theorem analysis establishes a Gaussian approximation for the ensembles' stochastic growth. The Gaussian approximation provides a generalized and corrected formulation of Heaps' law.

  12. Limits to wind power utilization.

    PubMed

    Gustavson, M R

    1979-04-01

    As wind energy receives increasing attention it is important to understand the noneconomic factors limiting the total power that can be extracted from the wind. These factors are examined here with a macroscopic approach. An upper global limit of 1.3 x 10(14) watts is arrived at with a sublimit of 2 x 10(12) watts for the continental United States. Some general conclusions are also reached regarding the sites that would have to be utilized to achieve these levels. Even within these limits, wind energy is seen to offer a potential far larger than many other self-renewing energy sources.

  13. Nuclear Structure at the Limits

    SciTech Connect

    Nazarewicz, Witold

    1997-12-31

    One of the frontiers of today`s nuclear science is the ``journey to the limits``: of atomic charge and nuclear mass, of neutron-to-proton ratio, and of angular momentum. The tour to the limits is not only a quest for new, exciting phenomena but the new data are expected, as well, to bring qualitatively new information about the fundamental properties of the nucleonic many-body system, the nature of the nuclear interaction, and nucleonic correlations at various energy-distance scales. In this talk, current developments in nuclear structure at the limits are discussed from a theoretical perspective.

  14. Careful telemedicine planning limits costly liability exposure.

    PubMed

    Edelstein, S A

    1999-12-01

    Recent Federal and state legislation and new payment opportunities from Medicare, Medicaid, and private payers may make it possible to offer telemedicine as a viable, cost-effective alternative to traditional care delivery in communities where access to health care is limited. Originally, nonexistent payment and expensive technology held back telemedicine but, these barriers are giving way to specific applications that can yield dramatic cost savings for group practices in the delivery of medical care while adding features and benefits not typically available in traditional delivery settings. Before joining a telemedicine network, group practices need to negotiate a variety of legal issues related to the corporate practice of medicine, patient confidentiality and privacy, malpractice, informed consent, licensure and credentialing, intellectual property, Medicare and Medicaid payment, fraud and abuse, medical device regulation, and antitrust.

  15. [The future of neonatology: possibilities and limitations].

    PubMed

    Bucher, Hans Ulrich

    2013-07-24

    Neonatology is a form of general medicine which focuses on the beginning of life and lays its main emphasis on the conversion from intrauterine to extrauterine life. Over the last 50 years, the neonatal mortality in Switzerland dropped from 25 to 3 per one-thousand liveborns. Today, the greatest challenges are extremely preterm infants and infants with complex malformations. Highly specialized intensive care enables survival in both high-risk groups but a significant number of children surviving with severe sequelae remain. This calls for research aiming at better understanding and supporting the adaptational changes and may simultaneously lead to ethical dilemmas about the limitation of intensive care. Since 1996, the Swiss Neonatal Network & Follow-up Group documents in high-risk infants the initial hospitalization at birth as well as the psychomotor development and quality of life until school age and beyond.

  16. Group collaboration in recognition memory.

    PubMed

    Clark, S E; Hori, A; Putnam, A; Martin, T P

    2000-11-01

    Group collaboration was examined in item and associative recognition. The present study distinguishes between group effects versus collaborative processes and defines the latter as interactive information exchange among group members. By that definition, many group effects do not involve collaboration. For example, group performance can exceed individual performance by pooling the increased resources of the group. Specifically, a group advantage can be obtained by deferring to a majority vote or to the group's best member. For both item and associative recognition, a group advantage was obtained that could not be accounted for by resource pooling. Collaborative facilitation was shown reliably in recognizing targets but not for rejecting distractors. PMID:11185784

  17. Gutzwiller renormalization group

    NASA Astrophysics Data System (ADS)

    Lanatà, Nicola; Yao, Yong-Xin; Deng, Xiaoyu; Wang, Cai-Zhuang; Ho, Kai-Ming; Kotliar, Gabriel

    2016-01-01

    We develop a variational scheme called the "Gutzwiller renormalization group" (GRG), which enables us to calculate the ground state of Anderson impurity models (AIM) with arbitrary numerical precision. Our method exploits the low-entanglement property of the ground state of local Hamiltonians in combination with the framework of the Gutzwiller wave function and indicates that the ground state of the AIM has a very simple structure, which can be represented very accurately in terms of a surprisingly small number of variational parameters. We perform benchmark calculations of the single-band AIM that validate our theory and suggest that the GRG might enable us to study complex systems beyond the reach of the other methods presently available and pave the way to interesting generalizations, e.g., to nonequilibrium transport in nanostructures.

  18. NOSS science working group

    NASA Astrophysics Data System (ADS)

    The members of the NOSS Science Working Group are John Apel, Pacific Marine Environmental Laboratories/NOAA; Tim Barnett, Scripps Institution of Oceanography; Francis Bretherton (chairman), National Center for Atmospheric Research; Otis Brown, University of Miami; Joost Businger, University of Washington; Garrett Campbell, NCAR; Mark Cane, Massachusetts Institute of Technology; Robert Edwards, National Marine Fisheries Service/NOAA; James Mueller, Naval Postgraduate School; Peter Niiler, Oregon State University; James J. O'Brien, Florida State University; Norman Phillips, National Meteorological Center/NOAA; Owen Phillips, The Johns Hopkins University; Stephen Piacsek, NSTL Station, NORDA; Trevor Platt, Bedford Institute of Oceanography; Stephen Pond, University of British Columbia; Stanley Ruttenberg (executive secretary), NCAR; William Schmitz, Woods Hole Oceanographic Institution; Jerry Schubel, State University of New York; Robert Stewart, Scripps; Norbert Untersteiner, NOAA; and Alan Weinstein, Naval Environmental Prediction Research Facility.

  19. Renormalization Group Tutorial

    NASA Technical Reports Server (NTRS)

    Bell, Thomas L.

    2004-01-01

    Complex physical systems sometimes have statistical behavior characterized by power- law dependence on the parameters of the system and spatial variability with no particular characteristic scale as the parameters approach critical values. The renormalization group (RG) approach was developed in the fields of statistical mechanics and quantum field theory to derive quantitative predictions of such behavior in cases where conventional methods of analysis fail. Techniques based on these ideas have since been extended to treat problems in many different fields, and in particular, the behavior of turbulent fluids. This lecture will describe a relatively simple but nontrivial example of the RG approach applied to the diffusion of photons out of a stellar medium when the photons have wavelengths near that of an emission line of atoms in the medium.

  20. The Group Tree of Experience.

    ERIC Educational Resources Information Center

    Ping, Ki

    1994-01-01

    Describes a group activity that uses a tree as a metaphor to reflect both group and personal growth during adventure activities. The tree's roots represent the group's formation, the branches and leaves represent the group's diversity and capabilities, and the seeds represent the personal learning and growth that took place within the group.…

  1. Introduction to Small Group Discussion.

    ERIC Educational Resources Information Center

    Millar, Dan Pyle

    To bring educational research into focus with tested classroom practice, this booklet provides an introduction to small group discussion. The theory and research section discusses the importance of small group discussion, characteristics of small group discussions, group attraction based on Maslow's hierarchy of basic human needs, group decision…

  2. Naive Theories of Social Groups

    ERIC Educational Resources Information Center

    Rhodes, Marjorie

    2012-01-01

    Four studies examined children's (ages 3-10, Total N = 235) naive theories of social groups, in particular, their expectations about how group memberships constrain social interactions. After introduction to novel groups of people, preschoolers (ages 3-5) reliably expected agents from one group to harm members of the other group (rather than…

  3. The Neuroscience of Group Membership

    ERIC Educational Resources Information Center

    Morrison, Samantha; Decety, Jean; Molenberghs, Pascal

    2012-01-01

    The present study aimed to uncover the neural activity associated with specific in-group and out-group word related stimuli, to examine the neuroanatomical basis of group membership concept representation, and investigate to what extent neural processes represent "in-group" differently from "out-group". Participants' brain activity was measured…

  4. New Developments in Group Counseling.

    ERIC Educational Resources Information Center

    Gladding, Samuel T., Ed.

    Group counseling is a rapidly changing field. This collection of 31 digests examines various aspects of group process and group counseling. The digests are arranged under different subject headings. In section 1, the nature of group work is examined, along with the evolution of group work training since 1990. The second section looks at…

  5. Limits to Open Class Performance?

    NASA Technical Reports Server (NTRS)

    Bowers, Albion H.

    2008-01-01

    This presentation discusses open or unlimited class aircraft performance limitations and design solutions. Limitations in this class of aircraft include slow climbing flight which requires low wing loading, high cruise speed which requires high wing loading, gains in induced or viscous drag alone which result in only half the gain overall and other structural problems (yaw inertia and spins, flutter and static loads integrity). Design solutions include introducing minimum induced drag for a given span (elliptical span load or winglets) and introducing minimum induced drag for a bell shaped span load. It is concluded that open class performance limits (under current rules and technologies) is very close to absolute limits, though some gains remain to be made from unexplored areas and new technologies.

  6. Model Misunderstandings. Teach the Limitations.

    ERIC Educational Resources Information Center

    Schamp, Homer W., Jr.

    1990-01-01

    Discussed is the idea that models should be taught by emphasizing limitations rather than focusing on their generality. Two examples of gas behavior models are included--the kinetic and static models. (KR)

  7. The Real Limits to Growth

    ERIC Educational Resources Information Center

    Ross, W. A.

    1975-01-01

    Fundamental conservation principles indicate existence of a limit to growth operative in the near future. General properties of geometric growth are presented with timescales showing population increases. Projections for natural and energy resource consumption are examined. (BP)

  8. Pumped limiter development on ISX

    SciTech Connect

    Mioduszewski, P.K.; Edmonds, P.H.; Sheffield, J.

    1981-01-01

    Pumped limiter configurations are being suggested for FED and INTOR for helium ash exhaust and fuel particle control. The goal of the pump limiter studies in ISX is the selection of the most promising concept and its evaluation in the ISX-C device under the following conditions: (1) quasi steady state operation (less than or equal to 30s), (2) high edge power densities, and (3) particle control by means of mechanical devices. We are considering various options, including particle scraper and ballistic particle collection concepts as well as the current FED design. In ISX-B we will test a full-size pump limiter and directly compare the heat removal and particle control capabilities with a bundle divertor. In ISX-C the steady state operation characteristics of pump limiters will be explored.

  9. Limits to Growth - Two Views

    ERIC Educational Resources Information Center

    Bulletin of the Atomic Scientists, 1972

    1972-01-01

    Comments by two reviewers (Garrett Hardin and Stephen Berry) on the book The Limits to Growth'' by Meadows and others. The nature of the models used, and the reactions of book reviewers are discussed. (AL)

  10. Limiting technology by negotiated agreement

    SciTech Connect

    Carnesale, A.

    1983-01-01

    The author concentrates on anti-ballistic missile (ABM) systems as an example of a continuing effort to limit technology by negotiated agreement. He first discusses the ABM treaty of 1972, ratified by both the US and the USSR. Afterwards, he briefly treats each of the following: ballistic missile defense (BMD) dilemmas; nature of the BMD choice; technology; economics; deterrence; nuclear warfighting; relations with allies; arms control; Star Wars; and on limiting technology.

  11. Limit cycle vibrations in turbomachinery

    NASA Technical Reports Server (NTRS)

    Ryan, S. G.

    1991-01-01

    The focus is on an examination of rotordynamic systems which are simultaneously susceptible to limit cycle instability and subharmonic response. Characteristics of each phenomenon are determined as well as their interrelationship. A normalized, single mass rotor model is examined as well as a complex model of the high pressure fuel turbopump and the Space Shuttle Main Engine. Entrainment of limit cycle instability by subharmonic response is demonstrated for both models. The nonuniqueness of the solution is also demonstrated.

  12. Passive fault current limiting device

    DOEpatents

    Evans, D.J.; Cha, Y.S.

    1999-04-06

    A passive current limiting device and isolator is particularly adapted for use at high power levels for limiting excessive currents in a circuit in a fault condition such as an electrical short. The current limiting device comprises a magnetic core wound with two magnetically opposed, parallel connected coils of copper, a high temperature superconductor or other electrically conducting material, and a fault element connected in series with one of the coils. Under normal operating conditions, the magnetic flux density produced by the two coils cancel each other. Under a fault condition, the fault element is triggered to cause an imbalance in the magnetic flux density between the two coils which results in an increase in the impedance in the coils. While the fault element may be a separate current limiter, switch, fuse, bimetal strip or the like, it preferably is a superconductor current limiter conducting one-half of the current load compared to the same limiter wired to carry the total current of the circuit. The major voltage during a fault condition is in the coils wound on the common core in a preferred embodiment. 6 figs.

  13. Passive fault current limiting device

    DOEpatents

    Evans, Daniel J.; Cha, Yung S.

    1999-01-01

    A passive current limiting device and isolator is particularly adapted for use at high power levels for limiting excessive currents in a circuit in a fault condition such as an electrical short. The current limiting device comprises a magnetic core wound with two magnetically opposed, parallel connected coils of copper, a high temperature superconductor or other electrically conducting material, and a fault element connected in series with one of the coils. Under normal operating conditions, the magnetic flux density produced by the two coils cancel each other. Under a fault condition, the fault element is triggered to cause an imbalance in the magnetic flux density between the two coils which results in an increase in the impedance in the coils. While the fault element may be a separate current limiter, switch, fuse, bimetal strip or the like, it preferably is a superconductor current limiter conducting one-half of the current load compared to the same limiter wired to carry the total current of the circuit. The major voltage during a fault condition is in the coils wound on the common core in a preferred embodiment.

  14. Upper Limit of Weights in TAI Computation

    NASA Technical Reports Server (NTRS)

    Thomas, Claudine; Azoubib, Jacques

    1996-01-01

    The international reference time scale International Atomic Time (TAI) computed by the Bureau International des Poids et Mesures (BIPM) relies on a weighted average of data from a large number of atomic clocks. In it, the weight attributed to a given clock depends on its long-term stability. In this paper the TAI algorithm is used as the basis for a discussion of how to implement an upper limit of weight for clocks contributing to the ensemble time. This problem is approached through the comparison of two different techniques. In one case, a maximum relative weight is fixed: no individual clock can contribute more than a given fraction to the resulting time scale. The weight of each clock is then adjusted according to the qualities of the whole set of contributing elements. In the other case, a parameter characteristic of frequency stability is chosen: no individual clock can appear more stable than the stated limit. This is equivalent to choosing an absolute limit of weight and attributing this to to the most stable clocks independently of the other elements of the ensemble. The first technique is more robust than the second and automatically optimizes the stability of the resulting time scale, but leads to a more complicated computatio. The second technique has been used in the TAI algorithm since the very beginning. Careful analysis of tests on real clock data shows that improvement of the stability of the time scale requires revision from time to time of the fixed value chosen for the upper limit of absolute weight. In particular, we present results which confirm the decision of the CCDS Working Group on TAI to increase the absolute upper limit by a factor of 2.5. We also show that the use of an upper relative contribution further helps to improve the stability and may be a useful step towards better use of the massive ensemble of HP 507IA clocks now contributing to TAI.

  15. Hanford single-shell tank grouping study

    SciTech Connect

    Remund, K.M.; Anderson, C.M.; Simpson, B.C.

    1995-10-01

    A tank grouping study has been conducted to find Hanford single-shell tanks with similar waste properties. The limited sampling resources of the characterization program could be allocated more effectively by having a better understanding of the groups of tanks that have similar waste types. If meaningful groups of tanks can be identified, tank sampling requirements may be reduced, and the uncertainty of the characterization estimates may be narrowed. This tank grouping study considers the analytical sampling information and the historical information that is available for all single-shell tanks. The two primary sources of historical characterization estimates and information come from the Historical Tank Content Estimate (HTCE) Model and the Sort on Radioactive Waste Tanks (SORWT) Model. The sampling and historical information are used together to come up with meaningful groups of similar tanks. Based on the results of analyses presented in this report, credible tank grouping looks very promising. Some groups defined using historical information (HTCE and SORWT) correspond well with those based on analytical data alone.

  16. Polytope Contractions within Weyl Group Symmetries

    NASA Astrophysics Data System (ADS)

    Szajewska, Marzena

    2016-09-01

    A general scheme for constructing polytopes is implemented here specifically for the classes of the most important 3D polytopes, namely those whose vertices are labeled by integers relative to a particular basis, here called the ω-basis. The actual number of non-isomorphic polytopes of the same group has no limit. To put practical bounds on the number of polytopes to consider for each group we limit our consideration to polytopes with dominant point (vertex) that contains only nonnegative integers in ω-basis. A natural place to start the consideration of polytopes from is the generic dominant weight which were all three coordinates are the lowest positive integer numbers. Contraction is a continuous change of one or several coordinates to zero.

  17. Explaining group-level traits requires distinguishing process from product.

    PubMed

    Panchanathan, Karthik; Mathew, Sarah; Perreault, Charles

    2014-06-01

    Smaldino is right to argue that we need a richer theory of group-level traits. He is wrong, however, in limiting group-level traits to units of cultural selection, which require explanations based on group selection. Traits are best understood when explanations focus on both process (i.e., selection) and product (i.e., adaptation). This approach can distinguish group-level traits that arise through within-group processes from those that arise through between-group processes. PMID:24970416

  18. Group Time: Taking a "Humor Break" at Group Time

    ERIC Educational Resources Information Center

    Church, Ellen Booth

    2005-01-01

    January is a perfect time to insert a strong dose of humor into group time gatherings. Oftentimes, children have tired of the predictable pattern of group meetings and need some change. Humor-filled group time activities can be the best secret remedy. Not only will children become more interested in the group time meetings (and therefore listen…

  19. Post-Disaster Social Justice Group Work and Group Supervision

    ERIC Educational Resources Information Center

    Bemak, Fred; Chung, Rita Chi-Ying

    2011-01-01

    This article discusses post-disaster group counseling and group supervision using a social justice orientation for working with post-disaster survivors from underserved populations. The Disaster Cross-Cultural Counseling model is a culturally responsive group counseling model that infuses social justice into post-disaster group counseling and…

  20. On Sufism, Sufi Group Study and Group Leadership.

    ERIC Educational Resources Information Center

    Einhorn, Jay

    1979-01-01

    Sufism is an ancient tradition of experiential human development. Sufi human development specialists utilize the group setting as a major study format. Comparison with group counseling might broaden perspectives on the possibilities and pitfalls of group process, and pinpoint several important issues relevant to group leadership. (Author)

  1. Group Leader Development: Effects of Personal Growth and Psychoeducational Groups

    ERIC Educational Resources Information Center

    Ohrt, Jonathan H.; Robinson, E. H., III; Hagedorn, W. Bryce

    2013-01-01

    The purpose of this quasi-experimental study was to compare the effects of personal growth groups and psychoeducational groups on counselor education students' (n = 74) empathy and group leader self-efficacy. Additionally, we compared the degree to which participants in each group valued: (a) cohesion, (b) catharsis, and (c) insight. There were no…

  2. Prostate Cancer Support Groups

    PubMed Central

    Chambers, Suzanne; Garrett, Bernie; Bottorff, Joan L.; McKenzie, Michael; Han, Christina S.; Ogrodniczuk, John S.

    2015-01-01

    To understand prostate cancer (PCa) specialists’ views about prostate cancer support groups (PCSGs), a volunteer sample of Canada-based PCa specialists (n = 150), including urologists (n = 100), radiation oncologists (n = 40), and medical oncologists (n = 10) were surveyed. The 56-item questionnaire used in this study included six sets of attitudinal items to measure prostate cancer specialists’ beliefs about positive and negative influences of PCSGs, reasons for attending PCSGs, the attributes of effective PCSGs, and the value of face-to-face and web-based PCSGs. In addition, an open-ended question was included to invite additional input from participants. Results showed that PCSGs were positively valued, particularly for information sharing, education and psychosocial support. Inclusivity, privacy, and accessibility were identified as potential barriers, and recommendations were made for better marketing PCSGs to increase engagement. Findings suggest prostate cancer specialists highly valued the role and potential benefits of face-to-face PCSGs. Information provision and an educational role were perceived as key benefits. Some concerns were expressed about the ability of web-based PCSGs to effectively engage and educate men who experience prostate cancer. PMID:25061087

  3. The analytic renormalization group

    NASA Astrophysics Data System (ADS)

    Ferrari, Frank

    2016-08-01

    Finite temperature Euclidean two-point functions in quantum mechanics or quantum field theory are characterized by a discrete set of Fourier coefficients Gk, k ∈ Z, associated with the Matsubara frequencies νk = 2 πk / β. We show that analyticity implies that the coefficients Gk must satisfy an infinite number of model-independent linear equations that we write down explicitly. In particular, we construct "Analytic Renormalization Group" linear maps Aμ which, for any choice of cut-off μ, allow to express the low energy Fourier coefficients for |νk | < μ (with the possible exception of the zero mode G0), together with the real-time correlators and spectral functions, in terms of the high energy Fourier coefficients for |νk | ≥ μ. Operating a simple numerical algorithm, we show that the exact universal linear constraints on Gk can be used to systematically improve any random approximate data set obtained, for example, from Monte-Carlo simulations. Our results are illustrated on several explicit examples.

  4. Reflexive Analysis of Groups

    NASA Astrophysics Data System (ADS)

    Lefebvre, Vladimir A.

    This chapter develops further a model I previously introduced, of an agent facing a choice between the positive and the negative poles. Here I will consider agents whose individual behavior depends on a ‘society’ compounded by all of them. Four ideas underlie the theory. The first idea is to consider relationships between the subgroups of agents, not just pairs of agents; this idea allows us to represent a decomposable graph corresponding to an agent or a group of agents as a tree of subgraphs. The second idea is to establish a correspondence between decomposable graphs and polynomials, allowing us to replace a tree of subgraphs with a tree of polynomials representing a computational process. The third idea consists of the interpretation of the tree of polynomials as an agent who has images of the self, which can have images of the self, etc. Finally, the fourth idea is putting an equation into correspondence to the agent, allowing us to find out the agent’s state. The theory is illustrated here with several examples from modern geopolitics, including scenarios of current interest.

  5. Emotional collectives: How groups shape emotions and emotions shape groups.

    PubMed

    van Kleef, Gerben A; Fischer, Agneta H

    2016-01-01

    Group settings are epicentres of emotional activity. Yet, the role of emotions in groups is poorly understood. How do group-level phenomena shape group members' emotional experience and expression? How are emotional expressions recognised, interpreted and shared in group settings? And how do such expressions influence the emotions, cognitions and behaviours of fellow group members and outside observers? To answer these and other questions, we draw on relevant theoretical perspectives (e.g., intergroup emotions theory, social appraisal theory and emotions as social information theory) and recent empirical findings regarding the role of emotions in groups. We organise our review according to two overarching themes: how groups shape emotions and how emotions shape groups. We show how novel empirical approaches break important new ground in uncovering the role of emotions in groups. Research on emotional collectives is thriving and constitutes a key to understanding the social nature of emotions.

  6. Experimental studies on pump limiters

    SciTech Connect

    Mioduszewski, P.

    1982-01-01

    Pump limiters are mechanical devices for He-ash removal, fuel particle control, and possibly impurity control. Different designs have been suggested by various authors over the past decade. However, the magnetic divertor concepts seemed to be more promising, mainly because of their remote plasma-material interactions. All of the characteristics of magnetic divertors have been proven experimentally, but the overall performance and complexity cause concern about their application to tokamak reactors. Consequently, it is time now to explore the potential of mechanical particle control devices, i.e. pump limiters. Because of the high recycling at the limiter, it is sufficient to exhaust only a small fraction, about 1 to 10%, of the limiter particle flux to remove e.g. He at its rate of production. Pump limiter experiments have been conducted so far on Alcator, PDX, Macrotor, and ISX. Depending on the experimental design, a pressure build-up of between 1 mTorr and 50 mTorr has been reported.

  7. 26 CFR 56.4911-10 - Members of a limited affiliated group of organizations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... sentence, whether an organization controls a second organization shall be determined by whether the second... must be made before the beginning of the second month after the close of each taxable year of the... the second month following the close of the taxable year of each such controlling organization,...

  8. Peer Groups, Power and Pedagogy: The Limits of an Educational Paradigm of Separation

    ERIC Educational Resources Information Center

    Hickey, Christopher; Keddie, Amanda

    2004-01-01

    In contrast to the plethora of literature that suggests that the increasing gulf between teachers and young people is due to the shifting interests and expectations of young people, the focus of this paper is on the roles teachers play in this relationship. Provoking our interest is a concern that some of the assumptions that underpin "mainstream"…

  9. 26 CFR 1.963-4 - Limitations on minimum distribution from a chain or group.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... and B pay foreign income tax at a flat rate of 20 percent and 30 percent, respectively. The 1966... tax at a flat rate of 20 percent, with no deduction being allowed for dividends received or paid. For... TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Controlled Foreign Corporations §...

  10. 26 CFR 56.4911-10 - Members of a limited affiliated group of organizations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) Grass roots expenditures. A controlling member organization for which the expenditure test election is in effect shall include in its grass roots expenditures for its taxable year the grass roots... name, identification number, and the lobbying expenditures and grass roots expenditures on...

  11. 26 CFR 56.4911-10 - Members of a limited affiliated group of organizations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) Grass roots expenditures. A controlling member organization for which the expenditure test election is in effect shall include in its grass roots expenditures for its taxable year the grass roots... name, identification number, and the lobbying expenditures and grass roots expenditures on...

  12. 26 CFR 1.963-4 - Limitations on minimum distribution from a chain or group.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... distributions equals at least $86.40 (0.90×0.48×$200); (2) Under the special rules of paragraphs (b) and (c) of... of $86.40 (0.90×0.48×$200) and the amount which the sum of such taxes would be if M Corporation were... section 78 and foreign tax credit: ($60.80/$80×$20) 15.20 ( + ) or ($10.64+$22.80) 33.44 48.64...

  13. Fermilab Steering Group Report

    SciTech Connect

    Steering Group, Fermilab; /Fermilab

    2007-12-01

    The Fermilab Steering Group has developed a plan to keep U.S. accelerator-based particle physics on the pathway to discovery, both at the Terascale with the LHC and the ILC and in the domain of neutrinos and precision physics with a high-intensity accelerator. The plan puts discovering Terascale physics with the LHC and the ILC as Fermilab's highest priority. While supporting ILC development, the plan creates opportunities for exciting science at the intensity frontier. If the ILC remains near the Global Design Effort's technically driven timeline, Fermilab would continue neutrino science with the NOvA experiment, using the NuMI (Neutrinos at the Main Injector) proton plan, scheduled to begin operating in 2011. If ILC construction must wait somewhat longer, Fermilab's plan proposes SNuMI, an upgrade of NuMI to create a more powerful neutrino beam. If the ILC start is postponed significantly, a central feature of the proposed Fermilab plan calls for building an intense proton facility, Project X, consisting of a linear accelerator with the currently planned characteristics of the ILC combined with Fermilab's existing Recycler Ring and the Main Injector accelerator. The major component of Project X is the linac. Cryomodules, radio-frequency distribution, cryogenics and instrumentation for the linac are the same as or similar to those used in the ILC at a scale of about one percent of a full ILC linac. Project X's intense proton beams would open a path to discovery in neutrino science and in precision physics with charged leptons and quarks. World-leading experiments would allow physicists to address key questions of the Quantum Universe: How did the universe come to be? Are there undiscovered principles of nature: new symmetries, new physical laws? Do all the particles and forces become one? What happened to the antimatter? Building Project X's ILC-like linac would offer substantial support for ILC development by accelerating the industrialization of ILC components

  14. Fermilab Steering Group Report

    SciTech Connect

    Beier, Eugene; Butler, Joel; Dawson, Sally; Edwards, Helen; Himel, Thomas; Holmes, Stephen; Kim, Young-Kee; Lankford, Andrew; McGinnis, David; Nagaitsev, Sergei; Raubenheimer, Tor; /SLAC /Fermilab

    2007-01-01

    The Fermilab Steering Group has developed a plan to keep U.S. accelerator-based particle physics on the pathway to discovery, both at the Terascale with the LHC and the ILC and in the domain of neutrinos and precision physics with a high-intensity accelerator. The plan puts discovering Terascale physics with the LHC and the ILC as Fermilab's highest priority. While supporting ILC development, the plan creates opportunities for exciting science at the intensity frontier. If the ILC remains near the Global Design Effort's technically driven timeline, Fermilab would continue neutrino science with the NOVA experiment, using the NuMI (Neutrinos at the Main Injector) proton plan, scheduled to begin operating in 2011. If ILC construction must wait somewhat longer, Fermilab's plan proposes SNuMI, an upgrade of NuMI to create a more powerful neutrino beam. If the ILC start is postponed significantly, a central feature of the proposed Fermilab plan calls for building an intense proton facility, Project X, consisting of a linear accelerator with the currently planned characteristics of the ILC combined with Fermilab's existing Recycler Ring and the Main Injector accelerator. The major component of Project X is the linac. Cryomodules, radio-frequency distribution, cryogenics and instrumentation for the linac are the same as or similar to those used in the ILC at a scale of about one percent of a full ILC linac. Project X's intense proton beams would open a path to discovery in neutrino science and in precision physics with charged leptons and quarks. World-leading experiments would allow physicists to address key questions of the Quantum Universe: How did the universe come to be? Are there undiscovered principles of nature: new symmetries, new physical laws? Do all the particles and forces become one? What happened to the antimatter? Building Project X's ILC-like linac would offer substantial support for ILC development by accelerating the industrialization of ILC components

  15. Possible nutrient limiting factor in long term operation of closed aquatic ecosystem

    NASA Astrophysics Data System (ADS)

    Hao, Zongjie; Li, Yanhui; Cai, Wenkai; Wu, Peipei; Liu, Yongding; Wang, Gaohong

    2012-03-01

    To investigate nutrient limitation effect on the community metabolism of closed aquatic ecosystem and possible nutrient limiting factors in the experimental food chains, depletion of inorganic chemicals including carbon, nitrogen and phosphorous was tested. A closed aquatic ecosystem lab module consisting of Chlorella pyrenoidosa and Chlamydomonas reinhardtii, Daphnia magna and associated unidentified microbes was established. Closed ecological systems receive no carbon dioxide; therefore, we presumed carbon as a first limiting factor. The results showed that the algae population in the nutrient saturated group was statistically higher than that in the nutrient limited groups, and that the chlorophyll a content of algae in the phosphorus limited group was the highest among the limited groups. However, the nitrogen limited group supported the most Daphnia, followed by the carbon limited group, the nutrient saturated group and the phosphorus limited group. Redundancy analysis showed that the total phosphorus contents were correlated significantly with the population of algae, and that the amount of soluble carbohydrate as feedback of nutrient depletion was correlated with the number of Daphnia. Thus, these findings suggest that phosphorus is the limiting factor in the operation of closed aquatic ecosystem. The results presented herein have important indications for the future construction of long term closed ecological system.

  16. The low noise limit in gene expression

    SciTech Connect

    Dar, Roy D.; Weinberger, Leor S.; Cox, Chris D.; Simpson, Michael L.; Razooky, Brandon S.

    2015-10-21

    Protein noise measurements are increasingly used to elucidate biophysical parameters. Unfortunately noise analyses are often at odds with directly measured parameters. Here we show that these inconsistencies arise from two problematic analytical choices: (i) the assumption that protein translation rate is invariant for different proteins of different abundances, which has inadvertently led to (ii) the assumption that a large constitutive extrinsic noise sets the low noise limit in gene expression. While growing evidence suggests that transcriptional bursting may set the low noise limit, variability in translational bursting has been largely ignored. We show that genome-wide systematic variation in translational efficiency can-and in the case of E. coli does-control the low noise limit in gene expression. Therefore constitutive extrinsic noise is small and only plays a role in the absence of a systematic variation in translational efficiency. Lastly, these results show the existence of two distinct expression noise patterns: (1) a global noise floor uniformly imposed on all genes by expression bursting; and (2) high noise distributed to only a select group of genes.

  17. The low noise limit in gene expression

    DOE PAGES

    Dar, Roy D.; Weinberger, Leor S.; Cox, Chris D.; Simpson, Michael L.; Razooky, Brandon S.

    2015-10-21

    Protein noise measurements are increasingly used to elucidate biophysical parameters. Unfortunately noise analyses are often at odds with directly measured parameters. Here we show that these inconsistencies arise from two problematic analytical choices: (i) the assumption that protein translation rate is invariant for different proteins of different abundances, which has inadvertently led to (ii) the assumption that a large constitutive extrinsic noise sets the low noise limit in gene expression. While growing evidence suggests that transcriptional bursting may set the low noise limit, variability in translational bursting has been largely ignored. We show that genome-wide systematic variation in translational efficiencymore » can-and in the case of E. coli does-control the low noise limit in gene expression. Therefore constitutive extrinsic noise is small and only plays a role in the absence of a systematic variation in translational efficiency. Lastly, these results show the existence of two distinct expression noise patterns: (1) a global noise floor uniformly imposed on all genes by expression bursting; and (2) high noise distributed to only a select group of genes.« less

  18. Limitations and implications of stream classification

    USGS Publications Warehouse

    Juracek, K.E.; Fitzpatrick, F.A.

    2003-01-01

    Stream classifications that are based on channel form, such as the Rosgen Level II classification, are useful tools for the physical description and grouping of streams and for providing a means of communication for stream studies involving scientists and (or) managers with different backgrounds. The Level II classification also is used as a tool to assess stream stability, infer geomorphic processes, predict future geomorphic response, and guide stream restoration or rehabilitation activities. The use of the Level II classification for these additional purposes is evaluated in this paper. Several examples are described to illustrate the limitations and management implications of the Level II classification. Limitations include: (1) time dependence, (2) uncertain applicability across physical environments, (3) difficulty in identification of a true equilibrium condition, (4) potential for incorrect determination of bankfull elevation, and (5) uncertain process significance of classification criteria. Implications of using stream classifications based on channel form, such as Rosgen's, include: (1) acceptance of the limitations, (2) acceptance of the risk of classifying streams incorrectly, and (3) classification results may be used inappropriately. It is concluded that use of the Level II classification for purposes beyond description and communication is not appropriate. Research needs are identified that, if addressed, may help improve the usefulness of the Level II classification.

  19. Limitations on quantum key repeaters.

    PubMed

    Bäuml, Stefan; Christandl, Matthias; Horodecki, Karol; Winter, Andreas

    2015-04-23

    A major application of quantum communication is the distribution of entangled particles for use in quantum key distribution. Owing to noise in the communication line, quantum key distribution is, in practice, limited to a distance of a few hundred kilometres, and can only be extended to longer distances by use of a quantum repeater, a device that performs entanglement distillation and quantum teleportation. The existence of noisy entangled states that are undistillable but nevertheless useful for quantum key distribution raises the question of the feasibility of a quantum key repeater, which would work beyond the limits of entanglement distillation, hence possibly tolerating higher noise levels than existing protocols. Here we exhibit fundamental limits on such a device in the form of bounds on the rate at which it may extract secure key. As a consequence, we give examples of states suitable for quantum key distribution but unsuitable for the most general quantum key repeater protocol.

  20. Limitations on quantum key repeaters.

    PubMed

    Bäuml, Stefan; Christandl, Matthias; Horodecki, Karol; Winter, Andreas

    2015-01-01

    A major application of quantum communication is the distribution of entangled particles for use in quantum key distribution. Owing to noise in the communication line, quantum key distribution is, in practice, limited to a distance of a few hundred kilometres, and can only be extended to longer distances by use of a quantum repeater, a device that performs entanglement distillation and quantum teleportation. The existence of noisy entangled states that are undistillable but nevertheless useful for quantum key distribution raises the question of the feasibility of a quantum key repeater, which would work beyond the limits of entanglement distillation, hence possibly tolerating higher noise levels than existing protocols. Here we exhibit fundamental limits on such a device in the form of bounds on the rate at which it may extract secure key. As a consequence, we give examples of states suitable for quantum key distribution but unsuitable for the most general quantum key repeater protocol. PMID:25903096

  1. On Setting Limits for Supersymmetry

    NASA Astrophysics Data System (ADS)

    Simeon, Paul; Toback, David

    2004-10-01

    When searching for new particles two separate production mechanisms from the same theory may produce the same final state. For example, in gauge mediated supersymmetry breaking with \\chi^0_1arrow γ tildeG at least two production mechanisms, \\chi^0_1\\chi^±1 and \\chi^0_2\\chi^±_1, can cascade to produce events with two photons and missing transverse energy. If there is no discovery one wants to set the best possible limits. While it seems obvious that the goal is to find the lowest possible cross section limit, one should be careful and focus on excluding the largest amount of parameter space for a theory. We show that the combined cross section limit from both (or all) production mechanisms that produce the same final state is the most sensitive way to attempt to exclude a theory.

  2. Tokamak plasma interaction with limiters

    NASA Astrophysics Data System (ADS)

    Pitcher, Charles Spencer

    1988-08-01

    The importance of plasma purity is discussed in terms of the general requirements of controlled thermonuclear fusion. The tokamak approach to fusion and its inherent problem of plasma contamination are introduced. A main source of impurities is due to the bombardment of the limiter by energetic particles and thus the three main aspects of the plasma-limiter interaction are reviewed, boundary plasma conditions, fueling/recycling and impurity production. The experiments, carried out on the DITE tokomak at Culham Laboratory, UK, investigated these three topics and the results are compared with predicted behavior; new physical phenomena are presented in all three areas.

  3. [Endoscopic urethrotomy: indications and limitations].

    PubMed

    Miñana López, Bernardino

    2014-01-01

    Endoscopic urethrotomy is a simple, reproducible, highly widespread technique that enables an appropriate management of patients with urethral stenosis, if the indication is well established. Determinants of success of this procedure are stenosis length, site, number, degree of spongiofibrosis and previous treatments. The best results would be obtained in single, short bulbar stenoses with limited spongiofibrosis, in which it may be the first choice. Its main limitation is the fact that the procedure itself is a controlled intentional trauma the result of which depends on multiple variables, including the technique employed.

  4. Human reproduction: dominion and limits.

    PubMed

    McCormick, Richard A

    1996-12-01

    The general struggle throughout Christian history has been to seek the proper balance between dominion and limits, intervention and nonintervention, givenness, and creativity. This struggle has worked itself out in six areas that touch human life. In this essay, I will revisit the Catholic tradition's treatment of these in terms of dominion and limits to see whether we can discern developmental patterns that might suggest an approach to issues pertaining to the sources of life (reproductive ethics) as we move into the next century.

  5. 2010 Chemical Working Group Status

    NASA Technical Reports Server (NTRS)

    Reid, Concha M.

    2010-01-01

    The Steering Group for the Interagency Advanced Power Group (IAPG) held their business meeting on November 30-December 1st in McLean, Virginia. Status reports were presented from each of the IAPG's Working Groups. These charts contain a brief summary of the IAPG Chemical Working Group's activities during 2010 and its plans for 2011.

  6. Study Groups: Conduit for Reform.

    ERIC Educational Resources Information Center

    Makibbin, Shirley S.; Sprague, Marsha M.

    This conference presentation describes study groups as a mechanism for changing teacher behavior. The history of study groups is discussed, beginning with the first American study groups organized by Benjamin Franklin; the Chautauqua Literary and Scientific Circle; the waning of study groups in the early 20th century as college enrollment…

  7. Marketing of Group Counseling Services.

    ERIC Educational Resources Information Center

    Wilson, F. Robert; And Others

    1987-01-01

    Provides social marketing guidelines for attracting members of appropriate target groups and encouraging their participation in group activities. Includes examination of the personal and social framework of the group counselor, elements of social marketing theory, a case study illustrating difficulties encountered by novice group counselors in…

  8. 26 CFR 56.4911-7 - Affiliated group of organizations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... organizations from being created for the purpose of avoiding the sliding-scale percentage limitation on an... the section 501(h) lobbying expenditure limits to members of an affiliated group of organizations...) of this section), (ii) Each of which is an eligible organization (within the meaning of §...

  9. 26 CFR 56.4911-7 - Affiliated group of organizations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... organizations from being created for the purpose of avoiding the sliding-scale percentage limitation on an... the section 501(h) lobbying expenditure limits to members of an affiliated group of organizations...) of this section), (ii) Each of which is an eligible organization (within the meaning of §...

  10. Refractive index of air. 2. Group index.

    PubMed

    Ciddor, P E; Hill, R J

    1999-03-20

    In a previous paper [Appl. Opt. 35, 1566 (1996)] one of us presented new equations for evaluation of the phase refractive index of air over a range of wavelengths and atmospheric parameters. That paper also gave an incorrect, although sufficiently accurate, procedure for calculating the group refractive index. Here we describe the results of a more rigorous derivation of the group index that takes proper account of the Lorentz-Lorenz formula, and we demonstrate that deviations from the Lorentz-Lorenz formula are insignificant to within a foreseeable precision of dispersion measurements for atmospheric conditions. We also derive and evaluate a simplification of the resultant equation that is useful for exploratory calculations. We clarify the limits of validity of the standard equation for the group refractive index and correct some minor errors in the previous paper.

  11. The care and feeding of small-group leaders of sex discussion groups.

    PubMed

    Held, J P; Rosenberg, P P

    1978-01-01

    This paper will focus on the selection, training, and monitoring of the small-group leaders in an extensive program of sex education. While not explicitly therapeutic, the leadership role in the six small-group sessions held during a 2-day period, covering highly emotional material, demands the skills and sensitivities of the traditional group therapist. In addition, group leaders must be aware of the limits of this experience and the subtle effect of a leader's role modeling during group discussion. The paper will discuss the SAR model, its academic history, and our experience with over 200 leaders drawn from both professional and paraprofessional ranks. We have data on participant evaluation of leaders and have developed a series of concepts regarding group process which is fed into our training program. Qualitative assessment of characteristics of the effective sex group leader is now possible as are basic group and member issues that most leaders must handle. The paper will discuss leadership screening, early orientation, small-group training sessions, practice leadership, supervision, evaluation, and problem solution in this highly sensitive area of sexuality, which while educational in purpose, is therapeutic in process. PMID:731715

  12. Focus group discussion: a tool for health and medical research.

    PubMed

    Wong, L P

    2008-03-01

    Focus group discussion is a research methodology in which a small group of participants gather to discuss a specified topic or an issue to generate data. The main characteristic of a focus group is the interaction between the moderator and the group, as well as the interaction between group members. The objective is to give the researcher an understanding of the participants' perspective on the topic in discussion. Focus groups are rapidly gaining popularity in health and medical research. This paper presents a general introduction of the use of focus groups as a research tool within the context of health research, with the intention of promoting its use among researchers in healthcare. A detailed methodology for the conduct of focus groups and analysis of focus group data are discussed. The potentials and limitations of this qualitative research technique are also highlighted.

  13. Structural Limits on Organizational Development

    ERIC Educational Resources Information Center

    Rice, George H., Jr.

    1977-01-01

    Organizational development practitioners tend to assume that all workplaces are pretty much alike, and that emotional health in all job situations can be described in approximately the same way. They have failed to recognize the sociological and structural/functional limitations of the workplace. (Author/JG)

  14. Active inrush-current limiter

    NASA Technical Reports Server (NTRS)

    Kichak, R. A.

    1977-01-01

    By stretching turn-on time from approximately 1 to 200 ms, effects of inrush current (and of associated large current spikes) and current rate of rise (dl/dt) are made potentially less severe. Limiter arrangement consists of time-variable impedance connected in series between input dc power source return and power circuit of converter.

  15. Limited Practice Respiratory Care Course.

    ERIC Educational Resources Information Center

    Anderson, Amy L.

    This 36-46 hour basic respiratory care course has been designed to enhance the skills of health professionals in providing limited respiratory care during those hours when a respiratory care practitioner is not available. Persons taking the course are assumed to have a basic knowledge of anatomy and physiology, administration of medications, and…

  16. 78 FR 37930 - Lending Limits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-25

    ... interim final rule published on June 21, 2012, 77 FR 37277, and extended on December 31, 2012, 77 FR 76841... limits for savings associations.\\4\\ \\2\\ 77 FR 37265 (June 21, 2012). \\3\\ The OCC has rulemaking authority... this deduction. See generally 76 FR 56508. 1. Loans to Non-Consolidated Subsidiaries The former...

  17. Oxidation Numbers and Their Limitations.

    ERIC Educational Resources Information Center

    Woolf, A. A.

    1988-01-01

    Reviews a method for determining oxidation numbers in covalent compounds and balancing mixed organic-inorganic or purely organic systems. Points out ambiguities presented when adjacent atoms have small or zero electronegativity differences. Presents other limitations that arise when using electronegativity values. (CW)

  18. Setting Time Limits on Tests

    ERIC Educational Resources Information Center

    van der Linden, Wim J.

    2011-01-01

    It is shown how the time limit on a test can be set to control the probability of a test taker running out of time before completing it. The probability is derived from the item parameters in the lognormal model for response times. Examples of curves representing the probability of running out of time on a test with given parameters as a function…

  19. Spectrometer design approaching the limit

    NASA Astrophysics Data System (ADS)

    Riesenberg, Rainer; Wuttig, Andreas; Peschel, Thomas; Damm, Christoph; Dobschal, Hans-Jürgen

    2008-09-01

    The design limits of grating array spectral sensors are discussed. The limit of a grating spectrometer with respect to the resolution is given by the diffraction limit of the grating. To approach the limit for the visible spectral region the entrance slits should reach a width of 2 μm and larger depending on wavelength and numerical aperture. The detector pixel sizes should be in the same range, which is achieved virtually by the discussed double array arrangement with a transmissive, static slit array and detector array. A number of techniques are applied for optimizing the performance as well as for miniaturization. A sub-pixel imaging including a sub-pixel analysis based on the double array arrangement virtually reduces the detector pixel sizes down to about 20%. To avoid the imaging aberrations the spectra is imaged from different entrance positions by the entrance slit array. The throughput can be increased by using a two dimensional entrance slit array, which includes a multiplex pattern or a fixed adaptive pattern. The design example of a UV-Raman spectral sensor is presented including spectral measurements.

  20. Illustrating the Central Limit Theorem

    ERIC Educational Resources Information Center

    Corcoran, Mimi

    2016-01-01

    Statistics is enjoying some well-deserved limelight across mathematics curricula of late. Some statistical concepts, however, are not especially intuitive, and students struggle to comprehend and apply them. As an AP Statistics teacher, the author appreciates the central limit theorem as a foundational concept that plays a crucial role in…

  1. Time-limited optimal dynamics beyond the quantum speed limit

    NASA Astrophysics Data System (ADS)

    Gajdacz, Miroslav; Das, Kunal K.; Arlt, Jan; Sherson, Jacob F.; Opatrný, Tomáš

    2015-12-01

    The quantum speed limit sets the minimum time required to transfer a quantum system completely into a given target state. At shorter times the higher operation speed results in a loss of fidelity. Here we quantify the trade-off between the fidelity and the duration in a system driven by a time-varying control. The problem is addressed in the framework of Hilbert space geometry offering an intuitive interpretation of optimal control algorithms. This approach leads to a necessary criterion for control optimality applicable as a measure of algorithm convergence. The time fidelity trade-off expressed in terms of the direct Hilbert velocity provides a robust prediction of the quantum speed limit and allows one to adapt the control optimization such that it yields a predefined fidelity. The results are verified numerically in a multilevel system with a constrained Hamiltonian and a classification scheme for the control sequences is proposed based on their optimizability.

  2. [Limits of resuscitation. I. Thanatophysiologic and therapeutic limits].

    PubMed

    Schneider, D

    1981-05-15

    Neither apodictic demands nor administration measures are suited to satisfy the various problems of the duty of treatment in the borderline region between life and death. An exact knowledge of the thanatophysiologic limits of the possibility of resuscitation during and after an anoxia and ischaemia is necessary. By effective cardiopulmonary measures of resuscitation, such as external heart massage with production of systolic pressure of 8-13 kPa as well as respiration with F1O2 1.0, the cardiac resuscitation time with immediate sufficiency (1. limit 4-41/2 min) may be prolonged to the cerebral resuscitation time from 8-10 minutes. Probably, the new concept of specific measures of cerebral resuscitation may definitively prolong also this 2nd limit. Furthermore, the fundamentals of the decision are discussed, for omitting or finishing a reanimation, or for reducing the intensive treatment. If the clinical syndrome of the dissociated cerebral death is present, without planned taking off an organ there is no necessity to render the finish of the intensive therapy dependent on legal regulations concerning the performance of organ transplantations.

  3. Limitations within "The Limits to Tree Height"1.

    PubMed

    Netting, Andrew G

    2009-02-01

    Koch et al. (Nature 428: 851-854) measured various parameters that were thought to limit the height of Sequoia sempervirens from northern California and concluded that the maximum height for this species is 122-130 m because within this range: (1) Irreversible embolism formation was proposed to occur when the xylem pressure was less than -1.9 MPa. (2) The leaf mass to area ratio exponentially approached 833 g×m(-2). (3) The discrimination against (13)CO(2) exponentially approached -20. (4) Light-saturated photosynthesis per unit leaf mass decreased to zero, indicating no net gain in leaf biomass. These conclusions are questioned here by reassessing the assumed limits to the biophysical parameters and by reexamining the proposed linear and exponential relationships between these parameters and tree height. It is concluded that: (1) Embolism repair mechanisms could have occurred at -2.7 MPa. (2) The leaf mass to area ratio could be a result of, rather than a determinant of, the large differential between cellular turgor and the xylem pressure. (3) The discrimination against (13)CO(2) may show two populations of foliage with apparent linear relationships with height rather than one exponential relationship. (4) The light-saturated photosynthesis per unit leaf mass as a measure of biomass investment in leaf expansion excludes investment in branch and trunk wood. As a result, tree height may be limited by a long-term balance between dieback and continued growth.

  4. Cultural differentiation does not entail group-level structure: The case for geographically explicit analysis.

    PubMed

    Ross, Robert Malcolm; Atkinson, Quentin Douglas

    2016-01-01

    Richerson et al. argue that relatively large cultural F ST values provide evidence for group structure and therefore scope for group selection. However, recent research on spatial patterns of cultural variation demonstrates that, as in the genetic case, apparent group structure can be a consequence of geographic clines, not group barriers. Such a pattern limits the scope for cultural group selection. PMID:27562351

  5. What Is a Group? Young Children's Perceptions of Different Types of Groups and Group Entitativity.

    PubMed

    Plötner, Maria; Over, Harriet; Carpenter, Malinda; Tomasello, Michael

    2016-01-01

    To date, developmental research on groups has focused mainly on in-group biases and intergroup relations. However, little is known about children's general understanding of social groups and their perceptions of different forms of group. In this study, 5- to 6-year-old children were asked to evaluate prototypes of four key types of groups: an intimacy group (friends), a task group (people who are collaborating), a social category (people who look alike), and a loose association (people who coincidently meet at a tram stop). In line with previous work with adults, the vast majority of children perceived the intimacy group, task group, and social category, but not the loose association, to possess entitativity, that is, to be a 'real group.' In addition, children evaluated group member properties, social relations, and social obligations differently in each type of group, demonstrating that young children are able to distinguish between different types of in-group relations. The origins of the general group typology used by adults thus appear early in development. These findings contribute to our knowledge about children's intuitive understanding of groups and group members' behavior. PMID:27010484

  6. Ability Grouping Plus Heterogeneous Grouping: Win-Win Schedules.

    ERIC Educational Resources Information Center

    Nolan, Fred

    1998-01-01

    Describes a type of block scheduling for middle schools that combines heterogeneous grouping in all subjects within the block and ability grouping. Presents a method of compiling data for block schedules to assist planning. (JPB)

  7. Communication Network Integration and Group Uniformity in a Complex Organization.

    ERIC Educational Resources Information Center

    Danowski, James A.; Farace, Richard V.

    This paper contains a discussion of the limitations of research on group processes in complex organizations and the manner in which a procedure for network analysis in on-going systems can reduce problems. The research literature on group uniformity processes and on theoretical models of these processes from an information processing perspective…

  8. Redecision Family Therapy: Its Use with Intensive Multiple Family Groups.

    ERIC Educational Resources Information Center

    Kadis, Leslie B.; McClendon, Ruth Ann

    1981-01-01

    Describes intensive multiple family group therapy which combines the advantages of group therapy with those of time-limited, goal-oriented approaches. Using the Redecision Family Therapy model further refines the technique by integrating the seemingly disparate methods of intra- psychic and systemic therapy. (Author)

  9. Interpreting Outcomes: Using Focus Groups in Evaluation Research

    ERIC Educational Resources Information Center

    Ansay, Sylvia J.; Perkins, Daniel F.; Nelson, John

    2004-01-01

    Although focus groups continue to gain popularity in marketing and social science research, their use in program evaluation has been limited. Here we demonstrate how focus groups can benefit evaluators, program staff, policy makers and administrators by providing an in-depth understanding of program effectiveness from the perspective of…

  10. When it is not a good fit: Clinical errors in patient selection and group composition in group psychotherapy.

    PubMed

    Kealy, David; Ogrodniczuk, John S; Piper, William E; Sierra-Hernandez, Carlos A

    2016-09-01

    Group psychotherapy provides unique opportunities for clinical errors in the selection of patients and composition of therapy groups. This article introduces some of the difficulties and complexities that can be associated with group composition and patient selection errors. Clinical vignettes from psychodynamic/interpersonal psychotherapy groups are used to illustrate three variations of group composition and selection errors. The first vignette depicts an error in selecting a disruptive patient into a fledgling group. The second vignette portrays an unsuccessful integration of a withdrawn, inhibited patient into an active, exploratory group. The third scenario illustrates challenges associated with poor quality of object relations in homogeneous group composition. Although research on group therapy composition and patient selection is limited, relevant empirical literature is integrated in our discussion of clinical implications and recommendations. (PsycINFO Database Record PMID:27631860

  11. Intensifying the Group Member's Experience Using the Group Log.

    ERIC Educational Resources Information Center

    Valine, Warren J.

    1983-01-01

    Presents the use of a group log in which members analyze the content and process of each session using a suggested format. The log promotes dialogue between the leader and each group member and involves members more fully in the group process. Feedback indicates the log is valuable. (JAC)

  12. Structuring the Group Experience: A Format for Designing Psychoeducational Groups.

    ERIC Educational Resources Information Center

    Furr, Susan R.

    2000-01-01

    Presents six-step model for moving from a general statement of purpose to a psychoeducational group design that includes didactic content, experiential activities, and processing. By following this model the group facilitator will be able to develop a psychoeducational group that provides a logical sequence of learning activities fostering…

  13. How Much "Group" Is There in Online Group Work?

    ERIC Educational Resources Information Center

    Lowes, Susan

    2014-01-01

    The ability to work in groups across time and space has become a frequent requirement for the workplace and is increasingly common in higher education, but there is a surprising lack of research on how online groups work. This research applies analytic approaches used in studies of face-to-face classroom "talk" to multiple groups in two…

  14. Group Assessment: Comparing Group and Individual Undergraduate Module Marks

    ERIC Educational Resources Information Center

    Almond, Richard J.

    2009-01-01

    This report describes a small study that analysed module marks of one cohort of science undergraduates from one academic year. It explored how group summative assessment marking affected the overall marks in comparison with individual assessment. A tutor allocated students to mixed ability project groups. Individual marks for the group work…

  15. Limited taste discrimination in Drosophila.

    PubMed

    Masek, Pavel; Scott, Kristin

    2010-08-17

    In the gustatory systems of mammals and flies, different populations of sensory cells recognize different taste modalities, such that there are cells that respond selectively to sugars and others to bitter compounds. This organization readily allows animals to distinguish compounds of different modalities but may limit the ability to distinguish compounds within one taste modality. Here, we developed a behavioral paradigm in Drosophila melanogaster to evaluate directly the tastes that a fly distinguishes. These studies reveal that flies do not discriminate among different sugars, or among different bitter compounds, based on chemical identity. Instead, flies show a limited ability to distinguish compounds within a modality based on intensity or palatability. Taste associative learning, similar to olfactory learning, requires the mushroom bodies, suggesting fundamental similarities in brain mechanisms underlying behavioral plasticity. Overall, these studies provide insight into the discriminative capacity of the Drosophila gustatory system and the modulation of taste behavior.

  16. Limitation and life in space

    NASA Astrophysics Data System (ADS)

    Israel, Marvin; Smith, T. Scott

    1986-08-01

    ``The Earth is the very quintescence of the human condition...,'' says Hannah Arendt. Georg Simmel writes: ``The stranger is by nature no `owner of soil'—soil not only in the physical, but also in the figurative sense of a life-substance which is fixed, if not in a point in space, at least in an ideal point of social environment.'' How will no longer being Earthbound affect persons' experience of themselves and of others? Space colonization offers an opportunity for new self-definition by the alteration of existing limits. Thus ``limitation'' is a useful concept for exploring the physical, social and psychological significance of the colonization of space. Will people seek the security of routine, of convention, of hierarchy as in the military model governing our present-day astronauts? or will they seek to maximize the freedom inherent in extraordinary living conditions—as bohemians, deviants, travelers?

  17. Binary optics: Trends and limitations

    NASA Technical Reports Server (NTRS)

    Farn, Michael W.; Veldkamp, Wilfrid B.

    1993-01-01

    We describe the current state of binary optics, addressing both the technology and the industry (i.e., marketplace). With respect to the technology, the two dominant aspects are optical design methods and fabrication capabilities, with the optical design problem being limited by human innovation in the search for new applications and the fabrication issue being limited by the availability of resources required to improve fabrication capabilities. With respect to the industry, the current marketplace does not favor binary optics as a separate product line and so we expect that companies whose primary purpose is the production of binary optics will not represent the bulk of binary optics production. Rather, binary optics' more natural role is as an enabling technology - a technology which will directly result in a competitive advantage in a company's other business areas - and so we expect that the majority of binary optics will be produced for internal use.

  18. Load limiting parachute inflation control

    SciTech Connect

    Redmond, J.; Hinnerichs, T.; Parker, G.

    1994-01-01

    Excessive deceleration forces experienced during high speed deployment of parachute systems can cause damage to the payload and the canopy fabric. Conventional reefing lines offer limited relief by temporarily restricting canopy inflation and limiting the peak deceleration load. However, the open-loop control provided by existing reefing devices restrict their use to a specific set of deployment conditions. In this paper, the sensing, processing, and actuation that are characteristic of adaptive structures form the basis of three concepts for active control of parachute inflation. These active control concepts are incorporated into a computer simulation of parachute inflation. Initial investigations indicate that these concepts promise enhanced performance as compared to conventional techniques for a nominal release. Furthermore, the ability of each controller to adapt to off-nominal release conditions is examined.

  19. Binary optics: Trends and limitations

    NASA Astrophysics Data System (ADS)

    Farn, Michael W.; Veldkamp, Wilfrid B.

    1993-08-01

    We describe the current state of binary optics, addressing both the technology and the industry (i.e., marketplace). With respect to the technology, the two dominant aspects are optical design methods and fabrication capabilities, with the optical design problem being limited by human innovation in the search for new applications and the fabrication issue being limited by the availability of resources required to improve fabrication capabilities. With respect to the industry, the current marketplace does not favor binary optics as a separate product line and so we expect that companies whose primary purpose is the production of binary optics will not represent the bulk of binary optics production. Rather, binary optics' more natural role is as an enabling technology - a technology which will directly result in a competitive advantage in a company's other business areas - and so we expect that the majority of binary optics will be produced for internal use.

  20. Surfactants at the Design Limit.

    PubMed

    Czajka, Adam; Hazell, Gavin; Eastoe, Julian

    2015-08-01

    This article analyzes how the individual structural elements of surfactant molecules affect surface properties, in particular, the point of reference defined by the limiting surface tension at the aqueous cmc, γcmc. Particular emphasis is given to how the chemical nature and structure of the hydrophobic tails influence γcmc. By comparing the three different classes of surfactants, fluorocarbon, silicone, and hydrocarbon, a generalized surface packing index is introduced which is independent of the chemical nature of the surfactants. This parameter ϕcmc represents the volume fraction of surfactant chain fragments in a surface film at the aqueous cmc. It is shown that ϕcmc is a useful index for understanding the limiting surface tension of surfactants and can be useful for designing new superefficient surfactants.

  1. Nuclear Structure at the Limits

    SciTech Connect

    Nazarewicz, W.

    1998-01-12

    One of the frontiers of today�s nuclear science is the �journey to the limits� of atomic charge and nuclear mass, of neutron-to-proton ratio, and of angular momentum. The tour to the limits is not only a quest for new, exciting phenomena, but the new data are expected, as well, to bring qualitatively new information about the fundamental properties of the nucleonic many-body system, the nature of the nuclear interaction, and nucleonic correlations at various energy-distance scales. In this series of lectures, current developments in nuclear structure at the limits are discussed from a theoretical perspective, mainly concentrating on medium-mass and heavy nuclei.

  2. Situated Assessment: Limitations and Promise

    ERIC Educational Resources Information Center

    Kreth, Melinda; Crawford, Mary Ann; Taylor, Marcy; Brockman, Elizabeth

    2010-01-01

    We present some key findings of a four-year, two-phase writing assessment project at Central Michigan University: Phase One (2002), a survey of faculty members (n=115) and subsequent focus groups (n=14) and Phase Two (2005), an evaluation of two samples of student writing (n=635 and 632). Major findings of Phase One reported here include the…

  3. Computation Beyond the Turing Limit

    NASA Astrophysics Data System (ADS)

    Siegelmann, Hava T.

    1995-04-01

    Extensive efforts have been made to prove the Church-Turing thesis, which suggests that all realizable dynamical and physical systems cannot be more powerful than classical models of computation. A simply described but highly chaotic dynamical system called the analog shift map is presented here, which has computational power beyond the Turing limit (super-Turing); it computes exactly like neural networks and analog machines. This dynamical system is conjectured to describe natural physical phenomena.

  4. Summary of Dissolved Concentration Limits

    SciTech Connect

    Yueting Chen

    2001-06-11

    According to the Technical Work Plan titled Technical Work Plan for Waste Form Degradation Process Model Report for SR (CRWMS M&O 2000a), the purpose of this study is to perform abstractions on solubility limits of radioactive elements based on the process-level information and thermodynamic databases provided by Natural Environment Program Operations (NEPO) and Waste Package Operations (WPO). The scope of this analysis is to produce solubility limits as functions, distributions, or constants for all transported radioactive elements identified by the Performance Assessment Operations (PAO) radioisotope screening. Results from an expert elicitation for solubility limits of most radioactive elements were used in the previous Total System Performance Assessments (TSPAs). However, the elicitation conducted in 1993 does not meet the criteria set forth by the U.S. Nuclear Regulatory Commission (NRC) due to lack of documentation and traceability (Kotra et al. 1996, Section 3). Therefore, at the Waste Form Abstraction Workshop held on February 2-4, 1999, at Albuquerque, New Mexico, the Yucca Mountain Site Characterization Project (YMP) decided to develop geochemical models to study solubility for the proposed Monitored Geologic Repository. WPO/NEPO is to develop process-level solubility models, including review and compilation of relevant thermodynamic data. PAO's responsibility is to perform abstractions based on the process models and chemical conditions and to produce solubility distributions or response surfaces applicable to the proposed repository. The results of this analysis and conceptual model will feed the performance assessment for Total System Performance Assessment--Site Recommendation (TSPA-SR) and Total System Performance Assessment--License Application (TSPA-LA), and to the Waste Form Degradation Process Model Report section on concentration limits.

  5. A speed limit for evolution.

    PubMed

    Worden, R P

    1995-09-01

    An upper bound on the speed of evolution is derived. The bound concerns the amount of genetic information which is expressed in observable ways in various aspects of the phenotype. The genetic information expressed in some part of the phenotype of a species cannot increase faster than a given rate, determined by the selection pressure on that part. This rate is typically a small fraction of a bit per generation. Total expressed genetic information cannot increase faster than a species-specific rate--typically a few bits per generation. These bounds apply to all aspects of the phenotype, but are particularly relevant to cognition. As brains are highly complex, we expect large amounts of expressed genetic information in the brain--of the order of 100 kilobytes--yet evolutionary changes in brain genetic information are only a fraction of a bit per generation. This has important consequences for cognitive evolution. The limit implies that the human brain differs from the chimpanzee brain by at most 5 kilobytes of genetic design information. This is not enough to define a Language Acquisition Device, unless it depends heavily on pre-existing primate symbolic cognition. Subject to the evolutionary speed limit, in changing environments a simple, modular brain architecture is fitter than more complex ones. This encourages us to look for simplicity in brain design, rather than expecting the brain to be a patchwork of ad hoc adaptations. The limit implies that pure species selection is not an important mechanism of evolutionary change.

  6. Photon and graviton mass limits

    NASA Astrophysics Data System (ADS)

    Goldhaber, Alfred Scharff; Nieto, Michael Martin

    2010-01-01

    Efforts to place limits on deviations from canonical formulations of electromagnetism and gravity have probed length scales increasing dramatically over time. Historically, these studies have passed through three stages: (1) testing the power in the inverse-square laws of Newton and Coulomb, (2) seeking a nonzero value for the rest mass of photon or graviton, and (3) considering more degrees of freedom, allowing mass while preserving explicit gauge or general-coordinate invariance. Since the previous review the lower limit on the photon Compton wavelength has improved by four orders of magnitude, to about one astronomical unit, and rapid current progress in astronomy makes further advance likely. For gravity there have been vigorous debates about even the concept of graviton rest mass. Meanwhile there are striking observations of astronomical motions that do not fit Einstein gravity with visible sources. “Cold dark matter” (slow, invisible classical particles) fits well at large scales. “Modified Newtonian dynamics” provides the best phenomenology at galactic scales. Satisfying this phenomenology is a requirement if dark matter, perhaps as invisible classical fields, could be correct here too. “Dark energy” might be explained by a graviton-mass-like effect, with associated Compton wavelength comparable to the radius of the visible universe. Significant mass limits are summarized in a table.

  7. Photon and graviton mass limits

    SciTech Connect

    Goldhaber, Alfred Scharff; Nieto, Michael Martin

    2010-01-15

    Efforts to place limits on deviations from canonical formulations of electromagnetism and gravity have probed length scales increasing dramatically over time. Historically, these studies have passed through three stages: (1) testing the power in the inverse-square laws of Newton and Coulomb, (2) seeking a nonzero value for the rest mass of photon or graviton, and (3) considering more degrees of freedom, allowing mass while preserving explicit gauge or general-coordinate invariance. Since the previous review the lower limit on the photon Compton wavelength has improved by four orders of magnitude, to about one astronomical unit, and rapid current progress in astronomy makes further advance likely. For gravity there have been vigorous debates about even the concept of graviton rest mass. Meanwhile there are striking observations of astronomical motions that do not fit Einstein gravity with visible sources. ''Cold dark matter'' (slow, invisible classical particles) fits well at large scales. ''Modified Newtonian dynamics'' provides the best phenomenology at galactic scales. Satisfying this phenomenology is a requirement if dark matter, perhaps as invisible classical fields, could be correct here too. ''Dark energy''might be explained by a graviton-mass-like effect, with associated Compton wavelength comparable to the radius of the visible universe. Significant mass limits are summarized in a table.

  8. Riemannian means on special euclidean group and unipotent matrices group.

    PubMed

    Duan, Xiaomin; Sun, Huafei; Peng, Linyu

    2013-01-01

    Among the noncompact matrix Lie groups, the special Euclidean group and the unipotent matrix group play important roles in both theoretic and applied studies. The Riemannian means of a finite set of the given points on the two matrix groups are investigated, respectively. Based on the left invariant metric on the matrix Lie groups, the geodesic between any two points is gotten. And the sum of the geodesic distances is taken as the cost function, whose minimizer is the Riemannian mean. Moreover, a Riemannian gradient algorithm for computing the Riemannian mean on the special Euclidean group and an iterative formula for that on the unipotent matrix group are proposed, respectively. Finally, several numerical simulations in the 3-dimensional case are given to illustrate our results.

  9. Cognitive Development and Group Stages.

    ERIC Educational Resources Information Center

    Saidla, Debie D.

    1990-01-01

    Attempts to integrate Perry's (1970) scheme of the cognitive development of college students with a model of group development adapted by Waldo (1985) based on Tuckman's (1965) formulation of developmental group stages. (Author)

  10. Substrate and nutrient limitation regulating microbial growth in soil

    NASA Astrophysics Data System (ADS)

    Bååth, Erland

    2015-04-01

    Microbial activity and growth in soil is regulated by several abiotic factors, including temperature, moisture and pH as the most important ones. At the same time nutrient conditions and substrate availability will also determine microbial growth. Amount of substrate will not only affect overall microbial growth, but also affect the balance of fungal and bacterial growth. The type of substrate will also affect the latter. Furthermore, according to Liebig law of limiting factors, we would expect one nutrient to be the main limiting one for microbial growth in soil. When this nutrient is added, the initial second liming factor will become the main one, adding complexity to the microbial response after adding different substrates. I will initially describe different ways of determining limiting factors for bacterial growth in soil, especially a rapid method estimating bacterial growth, using the leucine incorporation technique, after adding C (as glucose), N (as ammonium nitrate) and P (as phosphate). Scenarios of different limitations will be covered, with the bacterial growth response compared with fungal growth and total activity (respiration). The "degree of limitation", as well as the main limiting nutrient, can be altered by adding substrate of different stoichiometric composition. However, the organism group responding after alleviating the nutrient limitation can differ depending on the type of substrate added. There will also be situations, where fungi and bacteria appear to be limited by different nutrients. Finally, I will describe interactions between abiotic factors and the response of the soil microbiota to alleviation of limiting factors.

  11. Myrtaceae revisited: a reassessment of infrafamilial groups.

    PubMed

    Wilson, P G; O'Brien, M M; Gadek, P A; Quinn, C J

    2001-11-01

    Cladistic analyses are presented of matK sequence data as well as a nonmolecular database for an identical set of exemplar species chosen to represent the core genera or groups of genera in Myrtaceae. Eleven robust clades are recognized on the molecular data. Polyphyly of the previously recognized Metrosideros and Leptospermum alliances is confirmed, and several smaller informal taxonomic groupings are recognized from among the members of the former alliance, i.e., the Tristania, Tristaniopsis, Metrosideros, and Lophostemon groups. The nonmolecular analysis provides only limited resolution of relationships. A degree of congruence exists between the two analyses in that two separate fleshy-fruited clades, the Acmena and Myrtoid groups, are identified, as are the Eucalypt and Tristania groups, and Psiloxylon and Heteropyxis are the first lineages to diverge in both analyses. A combined analysis recognized all 11 clades that received strong support from the molecular data. A high level of homoplasy is revealed in many of the nonmolecular characters when they are examined against the combined estimate of phylogeny.

  12. Group Contribution Methods for Phase Equilibrium Calculations.

    PubMed

    Gmehling, Jürgen; Constantinescu, Dana; Schmid, Bastian

    2015-01-01

    The development and design of chemical processes are carried out by solving the balance equations of a mathematical model for sections of or the whole chemical plant with the help of process simulators. For process simulation, besides kinetic data for the chemical reaction, various pure component and mixture properties are required. Because of the great importance of separation processes for a chemical plant in particular, a reliable knowledge of the phase equilibrium behavior is required. The phase equilibrium behavior can be calculated with the help of modern equations of state or g(E)-models using only binary parameters. But unfortunately, only a very small part of the experimental data for fitting the required binary model parameters is available, so very often these models cannot be applied directly. To solve this problem, powerful predictive thermodynamic models have been developed. Group contribution methods allow the prediction of the required phase equilibrium data using only a limited number of group interaction parameters. A prerequisite for fitting the required group interaction parameters is a comprehensive database. That is why for the development of powerful group contribution methods almost all published pure component properties, phase equilibrium data, excess properties, etc., were stored in computerized form in the Dortmund Data Bank. In this review, the present status, weaknesses, advantages and disadvantages, possible applications, and typical results of the different group contribution methods for the calculation of phase equilibria are presented.

  13. [Marginality, ethnic groups and health].

    PubMed

    Corretger, J M; Fortuny, C; Botet, F; Valls, O

    1992-06-01

    Main marginated ethnic groups in Span are to be found among gypsies and 3rd world immigrants. The first group include about 250,000 persons and the second group more tan half a million people. Their origins and their being past of the less fortunate social layers made them a group of health risk. Pediatric pathologies are those favored by socio-economic shortcomings as well as hygienic-sanitary deficiencies. Imported pediatric pathologies have a small incident.

  14. Microbial extremophiles at the limits of life.

    PubMed

    Pikuta, Elena V; Hoover, Richard B; Tang, Jane

    2007-01-01

    Prokaryotic extremophiles were the first representatives of life on Earth and they are responsible for the genesis of geological structures during the evolution and creation of all currently known ecosystems. Flexibility of the genome probably allowed life to adapt to a wide spectrum of extreme environments. As a result, modern prokaryotic diversity formed in a framework of physico-chemical factors, and it is composed of: thermophilic, psychrophilic, acidophilic, alkaliphilic, halophilic, barophilic, and radioresistant species. This artificial systematics cannot reflect the multiple actions of different environmental factors since one organism could unite characteristics of several extreme-groups. In this review we show the current status of studies in all fields of extremophiles and summarize the limits of life for different species of microbial extremophiles. We also discuss the finding of extremophiles from unusual places such as soils, and briefly review recent studies of microfossils in meteorites in the context of the significance of microbial extremophiles to Astrobiology.

  15. Limitation of the diagnostic effort in paediatrics.

    PubMed

    Martínez González, Carmen

    2010-11-01

    The principle objective of a diagnosis is not to categorise symptoms, or group a combination of signs or clinical symptoms in a coherent way, but to cure a patient or improve their quality of life. Diagnoses that are technically correct, but do not seek this objective may become unnecessary labels which convert healthy people, or those who do not consider themselves to be sick, into patients. We propose a limitation of the diagnostic effort in order to reduce the iatrogenic consequences of these unnecessary labels or diagnoses, a new imperative which, in Kantian terms, can be expressed as: examine and treat your patients in such a way that, at the very least, the effects of your actions always improve the quality of their lives. PMID:20663755

  16. Limited Genetic Diversity of Brucella spp.

    PubMed Central

    Gándara, Benjamín; Merino, Ahidé López; Rogel, Marco Antonio; Martínez-Romero, Esperanza

    2001-01-01

    Multilocus enzyme electrophoresis (MLEE) of 99 Brucella isolates, including the type strains from all recognized species, revealed a very limited genetic diversity and supports the proposal of a monospecific genus. In MLEE-derived dendrograms, Brucella abortus and a marine Brucella sp. grouped into a single electrophoretic type related to Brucella neotomae and Brucella ovis. Brucella suis and Brucella canis formed another cluster linked to Brucella melitensis and related to Rhizobium tropici. The Brucella strains tested that were representatives of the six electrophoretic types had the same rRNA gene restriction fragment length polymorphism patterns and identical ribotypes. All 99 isolates had similar chromosome profiles as revealed by the Eckhardt procedure. PMID:11136777

  17. Group Theory: It's a SNAP.

    ERIC Educational Resources Information Center

    Huetinck, Linda

    1996-01-01

    Introduces concepts of modern algebraic group theory in the form of a game. Peg boards and rubber bands represent nonnumerical group elements and are manipulated under the operation of reorienting a regular polygon. Symmetry groups are used to explore set properties, as well as commutative and noncommutative operations. (CMS)

  18. Empowering Groups that Enable Play

    ERIC Educational Resources Information Center

    Wilson, David Sloan; Marshall, Danielle; Iserhott, Hindi

    2011-01-01

    Creating play environments for children usually requires groups of adults working together. An extensive scientific literature describes how groups function to achieve shared goals in general terms, and groups attempting to empower play may find this literature useful. Design principles for managing natural resources, identified by Elinor Ostrom…

  19. Group Cooperation in Outdoor Education

    ERIC Educational Resources Information Center

    Matthews, Bruce E.

    1978-01-01

    Utilizing the Beatles' Yellow Submarine fantasy (e.g., the Blue Meanies), this outdoor education program is designed for sixth graders and special education students. Activities developed at the Cortland Resident Outdoor Education Camp include a series of group stress/challenge activities to be accomplished by everyone in the group, as a group.…

  20. Suppose We Took Groups Seriously...

    ERIC Educational Resources Information Center

    Leavitt, Harold J.

    The idea of using groups, rather than individuals, as the basic building blocks for an organization is suggested in this paper. Although this idea is not new in theory, it is new in practice. To design an organization from scratch around groups appears to violate the American value of individualism. Groups, however, have advantages over…

  1. SOCIAL CHANGE THROUGH LISTENING GROUPS.

    ERIC Educational Resources Information Center

    OHLIGER, JOHN

    A LISTENING GROUP IS A GROUP OF ADULTS MEETING TOGETHER REGULARLY TO DISCUSS RADIO OR TELEVISION PROGRAMS, USUALLY UNDER LAY LEADERSHIP, SOMETIMES ASSISTED BY SUPPLEMENTAL PRINTED MATERIALS, WITH ARRANGEMENTS FOR TWO-WAY COMMUNICATION (FEEDBACK) BETWEEN THE LISTENERS AND BROADCASTERS. GROUPS APPEAL TO CLIENTELE NOT ORDINARILY ATTRACTED TO ADULT…

  2. Direct Sum Decomposition of Groups

    ERIC Educational Resources Information Center

    Thaheem, A. B.

    2005-01-01

    Direct sum decomposition of Abelian groups appears in almost all textbooks on algebra for undergraduate students. This concept plays an important role in group theory. One simple example of this decomposition is obtained by using the kernel and range of a projection map on an Abelian group. The aim in this pedagogical note is to establish a direct…

  3. Reading, Grouping, and the Student.

    ERIC Educational Resources Information Center

    Ediger, Marlow

    Reading instruction and placing students into groups emphasizes a plethora of approaches. Each method of grouping for instructional purposes should stress providing for learners' individual purposes. Which plans are appropriate for grouping students for reading instruction? Team teaching has many advocates, but it has both advantages and…

  4. Limits in decision making arise from limits in memory retrieval.

    PubMed

    Giguère, Gyslain; Love, Bradley C

    2013-05-01

    Some decisions, such as predicting the winner of a baseball game, are challenging in part because outcomes are probabilistic. When making such decisions, one view is that humans stochastically and selectively retrieve a small set of relevant memories that provides evidence for competing options. We show that optimal performance at test is impossible when retrieving information in this fashion, no matter how extensive training is, because limited retrieval introduces noise into the decision process that cannot be overcome. One implication is that people should be more accurate in predicting future events when trained on idealized rather than on the actual distributions of items. In other words, we predict the best way to convey information to people is to present it in a distorted, idealized form. Idealization of training distributions is predicted to reduce the harmful noise induced by immutable bottlenecks in people's memory retrieval processes. In contrast, machine learning systems that selectively weight (i.e., retrieve) all training examples at test should not benefit from idealization. These conjectures are strongly supported by several studies and supporting analyses. Unlike machine systems, people's test performance on a target distribution is higher when they are trained on an idealized version of the distribution rather than on the actual target distribution. Optimal machine classifiers modified to selectively and stochastically sample from memory match the pattern of human performance. These results suggest firm limits on human rationality and have broad implications for how to train humans tasked with important classification decisions, such as radiologists, baggage screeners, intelligence analysts, and gamblers.

  5. Likelihood Methods for Testing Group Problem Solving Models with Censored Data.

    ERIC Educational Resources Information Center

    Regal, Ronald R.; Larntz, Kinley

    1978-01-01

    Models relating individual and group problem solving solution times under the condition of limited time (time limit censoring) are presented. Maximum likelihood estimation of parameters and a goodness of fit test are presented. (Author/JKS)

  6. Global phylogeographic limits of Hawaii's avian malaria

    USGS Publications Warehouse

    Beadell, J.S.; Ishtiaq, F.; Covas, R.; Melo, M.; Warren, B.H.; Atkinson, C.T.; Bensch, S.; Graves, G.R.; Jhala, Y.V.; Peirce, M.A.; Rahmani, A.R.; Fonseca, D.M.; Fleischer, R.C.

    2006-01-01

    The introduction of avian malaria (Plasmodium relictum) to Hawaii has provided a model system for studying the influence of exotic disease on naive host populations. Little is known, however, about the origin or the genetic variation of Hawaii's malaria and traditional classification methods have confounded attempts to place the parasite within a global ecological and evolutionary context. Using fragments of the parasite mitochondrial gene cytochrome b and the nuclear gene dihydrofolate reductase-thymidylate synthase obtained from a global survey of greater than 13 000 avian samples, we show that Hawaii's avian malaria, which can cause high mortality and is a major limiting factor for many species of native passerines, represents just one of the numerous lineages composing the morphological parasite species. The single parasite lineage detected in Hawaii exhibits a broad host distribution worldwide and is dominant on several other remote oceanic islands, including Bermuda and Moorea, French Polynesia. The rarity of this lineage in the continental New World and the restriction of closely related lineages to the Old World suggest limitations to the transmission of reproductively isolated parasite groups within the morphological species. ?? 2006 The Royal Society.

  7. Correlation properties of loose groups

    SciTech Connect

    Maia, M.A.G.; Da Costa, L.N. )

    1990-02-01

    The two-point spatial correlation function for loose groups of galaxies is computed, using the recently compiled catalog of groups in the southern hemisphere. It is found that the correlation function for groups has a similar slope to that of galaxies but with a smaller amplitude, confirming an earlier result obtained from a similar analysis of the CfA group catalog. This implies that groups of galaxies are more randomly distributed than galaxies, which may be consistent with the predictions of Kashlinsky (1987) for a gravitational clustering scenario for the formation of large-scale structures. 21 refs.

  8. Citizen groups: a creative force

    SciTech Connect

    Stoel, T.

    1981-02-01

    The role of citizen groups is as important as that of government agencies when it comes to environmental policy in a democracy. These groups spend little money, yet they have initiated the major US environmental legislation of the past two decades. They are a recent, but effective, force in developing countries even though adversarial approaches are not often appropriate. The methods used by US environmental groups range from lobbying to confrontation in court. Groups outside the US tend to use consensus in democracies and information gathering in developing countries. While the groups' primary concerns are national in scope, international awareness and cooperation are growing. (DCK)

  9. Stereotypes of Norwegian social groups

    PubMed Central

    Bye, Hege H; Herrebrøden, Henrik; Hjetland, Gunnhild J; Røyset, Guro Ø; Westby, Linda L

    2014-01-01

    We present a pilot study and two main studies that address the nature of stereotypes of social groups in Norway within the framework of the Stereotype Content Model (SCM). The first study focused on stereotypes of a wide range of groups across categories such as gender, age, religious conviction, socioeconomic and health status. The second study focused on stereotypes of immigrant groups. Participants (n = 244 and n = 63, respectively) rated the groups on perceived warmth, competence, status, and competition. Results from both studies support the applicability of the SCM in Norway and provides a unique insight into stereotypes of Norwegian social groups. PMID:24975918

  10. Limits to Global Groundwater Consumption

    NASA Astrophysics Data System (ADS)

    Graaf, I. D.; Van Beek, R.; Sutanudjaja, E.; Wada, Y.; Bierkens, M. F.

    2015-12-01

    In regions with frequent water stress and large aquifer systems, groundwater is often used as an additional fresh water source. For many regions of the world groundwater abstraction exceeds groundwater recharge and persistent groundwater depletion occurs. The most direct effect of groundwater depletion is declining of water tables, leading to reduced groundwater discharge needed to sustain base-flow to e.g. rivers. Next to that, pumping costs increase, wells dry up and land subsidence occurs. These problems are expected to increase in the near future due to growing population and climate changes. This poses the urgent question of what the limits are of groundwater consumption worldwide. We simulate global water availability (5 arc-minute resolution, for 1960-2050) using the hydrological model PCR-GLOBWB (van Beek et al. 2011), coupled to a groundwater model based on MODFLOW (de Graaf et al. 2015), allowing for groundwater - surface water interactions. The groundwater model includes a parameterization of world's confined and unconfined aquifer systems needed for a realistic simulation of groundwater head dynamics. Water demands are included (from Wada et al. 2014). We study the limits to water consumption, focusing on locally attainable groundwater and groundwater levels critical to rivers to sustain low flows. We show an increasing trend (1960-2050) in groundwater head declines, due to increase in groundwater demand. Also, stream flow will decrease and low flow conditions will occur more frequent and will be longer in duration in the near future, especially for irrigated areas. Next to that, we provide a global overview of the years it takes until groundwater gets unattainable for e.g. a local farmer (100 m below land-surface used as a proxy), and estimate the increase in pumping cost for the near future. The results show where and when limits of groundwater consumption are reached globally.

  11. (Plant growth with limited water)

    SciTech Connect

    Not Available

    1991-01-01

    The work supported by DOE in the last year built on our earlier findings that stem growth in soybean subjected to limited water is inhibited first by a physical limitation followed in a few hours by metabolic changes that reduce the extensibility of the cell walls. With time, there is modest recovery in extensibility and a 28kD protein accumulates in the walls of the growth-affected cells. A 31kD protein that was 80% similar in amino acid sequence also was present but did not accumulate in the walls of the stem cells. Explorations of the mRNA for these proteins showed that the mRNA for the 28kD protein increased in the shoot in response to water deprivation but the mRNA for the 31kD protein did not accumulate. In contrast, the roots continued to grow and the mRNA for the 31kD protein accumulated but the mRNA for the 28kD protein was undetectable. We also explored how growth occurs in the absence of an external water supply. We found that, under these conditions, internal water is mobilized from surrounding nongrowing or slowly growing tissues and is used by rapidly growing cells. We showed that a low water potential is normally present in the enlarging tissues and is the likely force that extracts water from the surrounding tissues. We found that it involved a gradient in water potential that extended from the xylem to the outlying cells in the enlarging region and was not observed in the slowly growing basal tissue of the stems of the same plant. The gradient was measured directly with single cell determinations of turgor and osmotic potential in intact plants. The gradient may explain instances of growth inhibition with limited water when there is no change in the turgor of the enlarging cells. 17 refs.

  12. Inhomogeneous diffusion-limited aggregation

    NASA Technical Reports Server (NTRS)

    Selinger, Robin Blumberg; Nittmann, Johann; Stanley, H. E.

    1989-01-01

    It is demonstrated here that inhomogeneous diffusion-limited aggregation (DLA) model can be used to simulate viscous fingering in a medium with inhomogeneous permeability and homogeneous porosity. The medium consists of a pipe-pore square-lattice network in which all pores have equal volume and the pipes have negligible volume. It is shown that fluctuations in a DLA-based growth process may be tuned by noise reduction, and that fluctuations in the velocity of the moving interface are multiplicative in form.

  13. Limitations on practical quantum cryptography

    PubMed

    Brassard; Lutkenhaus; Mor; Sanders

    2000-08-01

    We provide limits to practical quantum key distribution, taking into account channel losses, a realistic detection process, and imperfections in the "qubits" sent from the sender to the receiver. As we show, even quantum key distribution with perfect qubits might not be achievable over long distances when the other imperfections are taken into account. Furthermore, existing experimental schemes (based on weak pulses) currently do not offer unconditional security for the reported distances and signal strength. Finally we show that parametric down-conversion offers enhanced performance compared to its weak coherent pulse counterpart.

  14. Gated compressor, distortionless signal limiter

    NASA Technical Reports Server (NTRS)

    Woodbury, R. C. (Inventor)

    1974-01-01

    A distortionless gated compressor for limiting the amplitude of a signal so as not to produce undesired signal levels responsive thereto is disclosed. The gated compressor includes a distortionless multiplier which multiplies an AC signal from a factor defined by a DC control signal. The compressor includes a plurality of channels each responsive to a signal produced in response to the multiplier's output. When the signal supplied to any channel exceeds a prescribed level, the level of the DC control signal is reduced to reduce the multiplier's output level and thereby prevent the signal applied to any channel from exceeding its prescribed level.

  15. Controlling secretion to limit chemoresistance.

    PubMed

    Georgilis, Athena; Gil, Jesús

    2016-08-15

    The tumor microenvironment influences cancer progression and therapy outcome by mechanisms not yet fully understood. In this issue of Genes & Development, Bent and colleagues (pp. 1811-1821) show how chemotherapy causes endothelial senescence. Interestingly, senescent endothelial cells do not mount a typical senescence-associated secretory phenotype but instead acutely secrete IL-6, promoting chemoresistance. This study unveils a physiological switch involving PI3K/AKT/mTOR signaling that restrains the senescence secretory responses to limit the detrimental consequences of persistent inflammation. PMID:27601527

  16. Modern Cosmology: Assumptions and Limits

    NASA Astrophysics Data System (ADS)

    Hwang, Jai-Chan

    2012-06-01

    Physical cosmology tries to understand the Universe at large with its origin and evolution. Observational and experimental situations in cosmology do not allow us to proceed purely based on the empirical means. We examine in which sense our cosmological assumptions in fact have shaped our current cosmological worldview with consequent inevitable limits. Cosmology, as other branches of science and knowledge, is a construct of human imagination reflecting the popular belief system of the era. The question at issue deserves further philosophic discussions. In Whitehead's words, ``philosophy, in one of its functions, is the critic of cosmologies.'' (Whitehead 1925).

  17. Controlling chaos with simple limiters

    PubMed

    Corron; Pethel; Hopper

    2000-04-24

    New experimental results demonstrate that chaos control can be accomplished using controllers that are very simple relative to the system being controlled. Chaotic dynamics in a driven pendulum and a double scroll circuit are controlled using an adjustable, passive limiter-a weight for the pendulum and a diode for the circuit. For both experiments, multiple unstable periodic orbits are selectively controlled using minimal perturbations. These physical examples suggest that chaos control can be practically applied to a much wider array of important problems than initially thought possible. PMID:11019218

  18. The darker side of groups.

    PubMed

    Thomas, Mike; Hynes, Celia

    2007-05-01

    This paper examines the role of group interaction in the workplace and the impact of anxiety on group cohesion. It takes a psychoanalytical perspective and highlights how early learning within a familial setting influences later attitudes and behaviour at work. In particular the article focuses on the signs of negative group anxiety and how the manager can recognise anti-group culture. By recognising the negative signs the leader can also come to understand how the anti-group develops and thereby prevent the resulting disruptive behaviour. In some instances the perception of anti-group feelings and behaviour can also be altered so that the team leader can reach a positive outcome for the group dynamic and resultant team cohesion and collaboration. PMID:17456166

  19. Little Groups of Preon Branes

    NASA Astrophysics Data System (ADS)

    MKRTCHYAN, H.; MKRTCHYAN, R.

    Little groups for preon branes (i.e. configurations of branes with maximal (n-1)/n fraction of survived supersymmetry) for dimensions d=2,3,…,11 are calculated for all massless, and partially for massive orbits. For massless orbits little groups are semidirect product of d-2 translational group Td-2 on a subgroup of (SO(d-2) × R-invariance) group. E.g. at d=9 the subgroup is exceptional G2 group. It is also argued, that 11D Majorana spinor invariants, which distinguish orbits, are actually invariant under d=2+10 Lorentz group. Possible applications of these results include construction of field theories in generalized spacetimes with brane charges coordinates, different problems of group's representations decompositions, spin-statistics issues.

  20. Does climate limit species richness by limiting individual species' ranges?

    PubMed

    Boucher-Lalonde, Véronique; Kerr, Jeremy T; Currie, David J

    2014-02-01

    Broad-scale geographical variation in species richness is strongly correlated with climate, yet the mechanisms underlying this correlation are still unclear. We test two broad classes of hypotheses to explain this pattern. Bottom-up hypotheses propose that the environment determines individual species' ranges. Ranges then sum up to yield species richness patterns. Top-down hypotheses propose that the environment limits the number of species that occur in a region, but not which ones. We test these two classes of hypotheses using a natural experiment: seasonal changes in environmental variables and seasonal range shifts of 625 migratory birds in the Americas. We show that richness seasonally tracks the environment. By contrast, individual species' geographical distributions do not. Rather, species occupy different sets of environmental conditions in two seasons. Our results are inconsistent with extant bottom-up hypotheses. Instead, a top-down mechanism appears to constrain the number of species that can occur in a given region.