Sample records for multiplication factor keff

  1. A useful observable for estimating keff in fast subcritical systems

    NASA Astrophysics Data System (ADS)

    Saracco, Paolo; Borreani, Walter; Chersola, Davide; Lomonaco, Guglielmo; Ricco, Gianni; Ripani, Marco

    2017-09-01

    The neutron multiplication factor keff is a key quantity to characterize subcritical neutron multiplying devices and for understanting their physical behaviour, being related to the fundamental eigenvalue of Boltzmann transport equation. Both the maximum available power - and all quantities related to it, like, e.g. the effectiveness in burning nuclear wastes - as well as reactor kinetics and dynamics depend on keff. Nevertheless, keff is not directly measurable and its determination results from the solution of an inverse problem: minimizing model dependence of the solution for keff then becomes a critical issue, relevant both for practical and theoretical reasons.

  2. Full core analysis of IRIS reactor by using MCNPX.

    PubMed

    Amin, E A; Bashter, I I; Hassan, Nabil M; Mustafa, S S

    2016-07-01

    This paper describes neutronic analysis for fresh fuelled IRIS (International Reactor Innovative and Secure) reactor by MCNPX code. The analysis included criticality calculations, radial power and axial power distribution, nuclear peaking factor and axial offset percent at the beginning of fuel cycle. The effective multiplication factor obtained by MCNPX code is compared with previous calculations by HELIOS/NESTLE, CASMO/SIMULATE, modified CORD-2 nodal calculations and SAS2H/KENO-V code systems. It is found that k-eff value obtained by MCNPX is closer to CORD-2 value. The radial and axial powers are compared with other published results carried out using SAS2H/KENO-V code. Moreover, the WIMS-D5 code is used for studying the effect of enriched boron in form of ZrB2 on the effective multiplication factor (K-eff) of the fuel pin. In this part of calculation, K-eff is calculated at different concentrations of Boron-10 in mg/cm at different stages of burnup of unit cell. The results of this part are compared with published results performed by HELIOS code. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Molybdenum-99 production calculation analysis of SAMOP reactor based on thorium nitrate fuel

    NASA Astrophysics Data System (ADS)

    Syarip; Togatorop, E.; Yassar

    2018-03-01

    SAMOP (Subcritical Assembly for Molybdenum-99 Production) has the potential to use thorium as fuel to produce 99Mo after modifying the design, but the production performance has not been discovered yet. A study needs to be done to obtain the correlation between 99Mo production with the mixed fuel composition of uranium and with SAMOP power on the modified SAMOP design. The study aims to obtain the production of 99Mo based thorium nitrate fuel on SAMOP’s modified designs. Monte Carlo N-Particle eXtended (MCNPX) is required to simulate the operation of the assembly by varying the composition of the uranium-thorium nitrate mixed fuel, geometry and power fraction on the SAMOP modified designs. The burnup command on the MCNPX is used to confirm the 99Mo production result. The assembly is simulated to operate for 6 days with subcritical neutron multiplication factor (keff = 0.97-0.99). The neutron multiplication factor of the modified design (keff) is 0.97, the activity obtained from 99Mo is 18.58 Ci at 1 kW power operation.

  4. Evaluation of the 235U prompt fission neutron spectrum including a detailed analysis of experimental data and improved model information

    NASA Astrophysics Data System (ADS)

    Neudecker, Denise; Talou, Patrick; Kahler, Albert C.; White, Morgan C.; Kawano, Toshihiko

    2017-09-01

    We present an evaluation of the 235U prompt fission neutron spectrum (PFNS) induced by thermal to 20-MeV neutrons. Experimental data and associated covariances were analyzed in detail. The incident energy dependence of the PFNS was modeled with an extended Los Alamos model combined with the Hauser-Feshbach and the exciton models. These models describe prompt fission, pre-fission compound nucleus and pre-equilibrium neutron emissions. The evaluated PFNS agree well with the experimental data included in this evaluation, preliminary data of the LANL and LLNL Chi-Nu measurement and recent evaluations by Capote et al. and Rising et al. However, they are softer than the ENDF/B-VII.1 (VII.1) and JENDL-4.0 PFNS for incident neutron energies up to 2 MeV. Simulated effective multiplication factors keff of the Godiva and Flattop-25 critical assemblies are further from the measured keff if the current data are used within VII.1 compared to using only VII.1 data. However, if this work is used with ENDF/B-VIII.0β2 data, simulated values of keff agree well with the measured ones.

  5. Nuclear Data Needs for the Neutronic Design of MYRRHA Fast Spectrum Research Reactor

    NASA Astrophysics Data System (ADS)

    Stankovskiy, A.; Malambu, E.; Van den Eynde, G.; Díez, C. J.

    2014-04-01

    A global sensitivity analysis of effective neutron multiplication factor to the change of nuclear data library has been performed. It revealed that the test version of JEFF-3.2 neutron-induced evaluated data library produces closer results to ENDF/B-VII.1 than JEFF-3.1.2 does. The analysis of contributions of individual evaluations into keff sensitivity resulted in the priority list of nuclides, uncertainties on cross sections and fission neutron multiplicities of which have to be improved by setting up dedicated differential and integral experiments.

  6. Comparative Studies on UO2 Fueled HTTR Several Nuclear Data Libraries

    NASA Astrophysics Data System (ADS)

    Hidayati, Anni N.; Prastyo, Puguh A.; Waris, Abdul; Irwanto, Dwi

    2017-07-01

    HTTR (High Temperature Engineering Test Reactor) is one of Generation IV nuclear reactors that has been developed by JAERI (former name of JAEA, JAPAN). HTTR uses graphite moderator, helium gas coolant with UO2 fuel and outlet coolant temperature of 900°C or higher than that. Several studies regarding HTTR have been performed by employing JENDL 3.2 nuclear data libraries. In this paper, comparative evaluation of HTTR with several nuclear data libraries (JENDL 3.3, JENDL 4.0, and JEF 3.1) have been conducted.. The 3-D calculation was performed by using CITATION module of SRAC 2006 code. The result shows some differences between those nuclear data libraries result. K-eff or core effective multiplication factor results are about 1.17, 1,18 and 1,19 (JENDL 3.3, JENDL 4.0, and JEF 3.1) at Begin of Life, also at the End of Life (after two years operation) are 1.16, 1.17 and 1.17 for each nuclear data libraries. There are some different result of K-eff but for neutron spectra results, those nuclear data libraries show the same result.

  7. Results of a Neutronic Simulation of HTR-Proteus Core 4.2 using PEBBED and other INL Reactor Physics Tools: FY-09 Report

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

    Hans D. Gougar

    The Idaho National Laboratory’s deterministic neutronics analysis codes and methods were applied to the computation of the core multiplication factor of the HTR-Proteus pebble bed reactor critical facility. A combination of unit cell calculations (COMBINE-PEBDAN), 1-D discrete ordinates transport (SCAMP), and nodal diffusion calculations (PEBBED) were employed to yield keff and flux profiles. Preliminary results indicate that these tools, as currently configured and used, do not yield satisfactory estimates of keff. If control rods are not modeled, these methods can deliver much better agreement with experimental core eigenvalues which suggests that development efforts should focus on modeling control rod andmore » other absorber regions. Under some assumptions and in 1D subcore analyses, diffusion theory agrees well with transport. This suggests that developments in specific areas can produce a viable core simulation approach. Some corrections have been identified and can be further developed, specifically: treatment of the upper void region, treatment of inter-pebble streaming, and explicit (multiscale) transport modeling of TRISO fuel particles as a first step in cross section generation. Until corrections are made that yield better agreement with experiment, conclusions from core design and burnup analyses should be regarded as qualitative and not benchmark quality.« less

  8. Analysis of 238Pu and 56Fe Evaluated Data for Use in MYRRHA

    NASA Astrophysics Data System (ADS)

    Díez, C. J.; Cabellos, O.; Martínez, J. S.; Stankovskiy, A.; Van den Eynde, G.; Schillebeeckx, P.; Heyse, J.

    2014-04-01

    A sensitivity analysis on the multiplication factor, keff, to the cross section data has been carried out for the MYRRHA critical configuration in order to show the most relevant reactions. With these results, a further analysis on the 238Pu and 56Fe cross sections has been performed, comparing the evaluations provided in the JEFF-3.1.2 and ENDF/B-VII.1 libraries for these nuclides. Then, the effect in MYRRHA of the differences between evaluations are analysed, presenting the source of the differences. With these results, recommendations for the 56Fe and 238Pu evaluations are suggested. These calculations have been performed with SCALE6.1 and MCNPX-2.7e.

  9. Unusual enhancement of effective magnetic anisotropy with decreasing particle size in maghemite nanoparticles

    NASA Astrophysics Data System (ADS)

    Pisane, K. L.; Singh, Sobhit; Seehra, M. S.

    2017-05-01

    In magnetic nanoparticles (NPs), the observed increase in the effective magnetic anisotropy Keff with the decrease in particle size D is often interpreted, sometimes unsuccessfully, using the equation Keff = Kb + (6KS/D), where Kb is the bulk-like anisotropy of the core spins and KS is the anisotropy of spins in the surface layer. Here, we test the validity of this relation in γ-Fe2O3 NPs for sizes D from 15 nm to 2.5 nm. The samples include oleic acid-coated NPs with D = 2.5, 3.4, 6.3, and 7.0 nm investigated here, with results on 14 other sizes taken from literature. Keff is determined from the analysis of the frequency dependence of the blocking temperature TB after considering the effects of interparticle interactions on TB. For the γ-Fe2O3 NPs with D < 5 nm, an unusual enhancement of Keff with decreasing D, well above the magnitudes predicted by the above equation, is observed. Instead the variation of Keff vs. D is best described by an extension of the above equation by including Ksh term from spins in a shell of thickness d. Based on this core-shell-surface layer model, the data are fit to the equation Keff = Kb + (6KS/D) + Ksh{[1-(2d/D)]-3-1} with Kb = 1.9 × 105 ergs/cm3, KS = 0.035 ergs/cm2, and Ksh = 1.057 × 104 ergs/cm3 as the contribution of spins in the shell of thickness d = 1.1 nm. Significance of this result is discussed.

  10. Balancing anisotropic curvature with gauge fields in a class of shear-free cosmological models

    NASA Astrophysics Data System (ADS)

    Thorsrud, Mikjel

    2018-05-01

    We present a complete list of general relativistic shear-free solutions in a class of anisotropic, spatially homogeneous and orthogonal cosmological models containing a collection of n independent p-form gauge fields, where p\\in\\{0, 1, 2, 3\\} , in addition to standard ΛCDM matter fields modelled as perfect fluids. Here a (collection of) gauge field(s) balances anisotropic spatial curvature on the right-hand side of the shear propagation equation. The result is a class of solutions dynamically equivalent to standard FLRW cosmologies, with an effective curvature constant Keff that depends both on spatial curvature and the energy density of the gauge field(s). In the case of a single gauge field (n  =  1) we show that the only spacetimes that admit such solutions are the LRS Bianchi type III, Bianchi type VI0 and Kantowski–Sachs metric, which are dynamically equivalent to open (Keff<0 ), flat (Keff=0 ) and closed (Keff>0 ) FLRW models, respectively. With a collection of gauge fields (n  >  1) also Bianchi type II admits a shear-free solution (Keff>0 ). We identify the LRS Bianchi type III solution to be the unique shear-free solution with a gauge field Hamiltonian bounded from below in the entire class of models.

  11. Isotope Mixes, Corresponding Nuclear Properties and Reactor Design Implications of Naturally Occurring Lead Sources

    DTIC Science & Technology

    2013-06-01

    39  Table 8.  Required enrichment for criticality ...keff ~ 1)-1. ...............................................44  Table 9.  Required enrichment for criticality (keff ~ 1)-2...45  Table 10.  Required enrichment for SSTAR based model reactor to achieve criticality using various natural lead concentrations

  12. Fatigue Analyses Under Constant- and Variable-Amplitude Loading Using Small-Crack Theory

    NASA Technical Reports Server (NTRS)

    Newman, J. C., Jr.; Phillips, E. P.; Everett, R. A., Jr.

    1999-01-01

    Studies on the growth of small cracks have led to the observation that fatigue life of many engineering materials is primarily "crack growth" from micro-structural features, such as inclusion particles, voids, slip-bands or from manufacturing defects. This paper reviews the capabilities of a plasticity-induced crack-closure model to predict fatigue lives of metallic materials using "small-crack theory" under various loading conditions. Constraint factors, to account for three-dimensional effects, were selected to correlate large-crack growth rate data as a function of the effective stress-intensity factor range (delta-Keff) under constant-amplitude loading. Modifications to the delta-Keff-rate relations in the near-threshold regime were needed to fit measured small-crack growth rate behavior. The model was then used to calculate small-and large-crack growth rates, and to predict total fatigue lives, for notched and un-notched specimens under constant-amplitude and spectrum loading. Fatigue lives were predicted using crack-growth relations and micro-structural features like those that initiated cracks in the fatigue specimens for most of the materials analyzed. Results from the tests and analyses agreed well.

  13. Dynamic Failure of Materials: A Review

    DTIC Science & Technology

    2010-08-01

    stress states . It is currently unknown how well the current trend of multi-scale modeling will impact dynamic failure; however... stress can exist in the necked region after a neck is formed due to the nonuniformity of the necked region. This triaxial stress state is extremely...7 into 8, the effective stress intensity factor (Keff) can be determined in terms of the stress intensity factor (K). Because the onset of

  14. Effects of materials and design on the criticality and shielding assessment of canister concepts for the disposal of spent nuclear fuel.

    PubMed

    Gutiérrez, Miguel Morales; Caruso, Stefano; Diomidis, Nikitas

    2018-05-19

    According to the Swiss disposal concept, the safety of a deep geological repository for spent nuclear fuel (SNF) is based on a multi-barrier system. The disposal canister is an important component of the engineered barrier system, aiming to provide containment of the SNF for thousands of years. This study evaluates the criticality safety and shielding of candidate disposal canister concepts, focusing on the fulfilment of the sub-criticality criterion and on limiting radiolysis processes at the outer surface of the canister which can enhance corrosion mechanisms. The effective neutron multiplication factor (k-eff) and the surface dose rates are calculated for three different canister designs and material combinations for boiling water reactor (BWR) canisters, containing 12 spent fuel assemblies (SFA), and pressurized water reactor (PWR) canisters, with 4 SFAs. For each configuration, individual criticality and shielding calculations were carried out. The results show that k-eff falls below the defined upper safety limit (USL) of 0.95 for all BWR configurations, while staying above USL for the PWR ones. Therefore, the application of a burnup credit methodology for the PWR case is required, being currently under development. Relevant is also the influence of canister material and internal geometry on criticality, enabling the identification of safer fuel arrangements. For a final burnup of 55MWd/kgHM and 30y cooling time, the combined photon-neutron surface dose rate is well below the threshold of 1 Gy/h defined to limit radiation-induced corrosion of the canister in all cases. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Results of the Simulation of the HTR-Proteus Core 4.2 Using PEBBED-COMBINE: FY10 Report

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

    Hans Gougar

    2010-07-01

    ABSTRACT The Idaho National Laboratory’s deterministic neutronics analysis codes and methods were applied to the computation of the core multiplication factor of the HTR-Proteus pebble bed reactor critical facility. This report is a follow-on to INL/EXT-09-16620 in which the same calculation was performed but using earlier versions of the codes and less developed methods. In that report, results indicated that the cross sections generated using COMBINE-7.0 did not yield satisfactory estimates of keff. It was concluded in the report that the modeling of control rods was not satisfactory. In the past year, improvements to the homogenization capability in COMBINE havemore » enabled the explicit modeling of TRIS particles, pebbles, and heterogeneous core zones including control rod regions using a new multi-scale version of COMBINE in which the 1-dimensional discrete ordinate transport code ANISN has been integrated. The new COMBINE is shown to yield benchmark quality results for pebble unit cell models, the first step in preparing few-group diffusion parameters for core simulations. In this report, the full critical core is modeled once again but with cross sections generated using the capabilities and physics of the improved COMBINE code. The new PEBBED-COMBINE model enables the exact modeling of the pebbles and control rod region along with better approximation to structures in the reflector. Initial results for the core multiplication factor indicate significant improvement in the INL’s tools for modeling the neutronic properties of a pebble bed reactor. Errors on the order of 1.6-2.5% in keff are obtained; a significant improvement over the 5-6% error observed in the earlier This is acceptable for a code system and model in the early stages of development but still too high for a production code. Analysis of a simpler core model indicates an over-prediction of the flux in the low end of the thermal spectrum. Causes of this discrepancy are under investigation. New homogenization techniques and assumptions were used in this analysis and as such, they require further confirmation and validation. Further refinement and review of the complex Proteus core model are likely to reduce the errors even further.« less

  16. Nonquaternary Cholinesterase Reactivators.

    DTIC Science & Technology

    1982-08-30

    c, a plot (not shown) of pKa versus Hammet substituent constant (a )42 is also linear and conforms p to equation (5) pKa - (7.63 ±0.02) - (.63 ±0.05...dissociates to the active oximate form, we have defined an effective bimolecular reactivation rate constant as in equation (6) keff ’ kb [1 + antilog(pKa...type 1 compounds generally exhibit low activity as reactivators. In terms of keff values [see equation (6)] for reactivation of ethyl methylphosphonyl

  17. Effect of Neutron Absorbers Mixed in or Coating the Fuel of a 1-MWt Lithium-Cooled Space Reactor

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

    Amiri, Benjamin W.; Los Alamos National Laboratory, Los Alamos, NM 87545; Poston, David I.

    2005-02-06

    The goal of this study was to determine the effect of various neutron poisons (boron, dysprosium, erbium, and gadolinium) on a 1-MWt, lithium-cooled liquid-metal reactor. The isotopes were considered to be in-fuel poisons, as well as poisons coating the fuel. One way to quantify the effectiveness of a poison in meeting accident-condition requirements is by defining the safety margin as the difference between keff at the beginning of life and keff during the accident scenarios. The isotope that showed the most potential in increasing the safety margin for the wet-sand/water case was 157Gd. The safety margin was 10%-20% greater usingmore » 157Gd as an in-fuel poison as opposed to a coating, depending on the poison quantity. However, the most limiting condition (i.e., the accident scenario with the highest keff, thus the lowest safety margin) is when the reactor is submerged in wet sand. None of the isotopes considered significantly affected the safety margin for the dry-sand case. However, the poison isotopes considered may have applicability for meeting the wet-sand/water keff requirements or as burnable poisons in a moderated system. The views expressed in this document are those of the author and do not necessarily reflect agreement by the government.« less

  18. Validation of DRAGON4/DONJON4 simulation methodology for a typical MNSR by calculating reactivity feedback coefficient and neutron flux

    NASA Astrophysics Data System (ADS)

    Al Zain, Jamal; El Hajjaji, O.; El Bardouni, T.; Boukhal, H.; Jaï, Otman

    2018-06-01

    The MNSR is a pool type research reactor, which is difficult to model because of the importance of neutron leakage. The aim of this study is to evaluate a 2-D transport model for the reactor compatible with the latest release of the DRAGON code and 3-D diffusion of the DONJON code. DRAGON code is then used to generate the group macroscopic cross sections needed for full core diffusion calculations. The diffusion DONJON code, is then used to compute the effective multiplication factor (keff), the feedback reactivity coefficients and neutron flux which account for variation in fuel and moderator temperatures as well as the void coefficient have been calculated using the DRAGON and DONJON codes for the MNSR research reactor. The cross sections of all the reactor components at different temperatures were generated using the DRAGON code. These group constants were used then in the DONJON code to calculate the multiplication factor and the neutron spectrum at different water and fuel temperatures using 69 energy groups. Only one parameter was changed where all other parameters were kept constant. Finally, Good agreements between the calculated and measured have been obtained for every of the feedback reactivity coefficients and neutron flux.

  19. The MARVEL assembly for neutron multiplication.

    PubMed

    Chichester, David L; Kinlaw, Mathew T

    2013-10-01

    A new multiplying test assembly is under development at Idaho National Laboratory to support research, validation, evaluation, and learning. The item is comprised of three stacked, highly-enriched uranium (HEU) cylinders, each 11.4 cm in diameter and having a combined height of up to 11.7 cm. The combined mass of all three cylinders is 20.3 kg of HEU. Calculations for the bare configuration of the assembly indicate a multiplication level of >3.5 (k(eff)=0.72). Reflected configurations of the assembly, using either polyethylene or tungsten, are possible and have the capability of raising the assembly's multiplication level to greater than 10. This paper describes simulations performed to assess the assembly's multiplication level under different conditions and describes the resources available at INL to support the use of these materials. We also describe some preliminary calculations and test activities using the assembly to study neutron multiplication. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Electromechanical coupling factor of capacitive micromachined ultrasonic transducers.

    PubMed

    Caronti, Alessandro; Carotenuto, Riccardo; Pappalardo, Massimo

    2003-01-01

    Recently, a linear, analytical distributed model for capacitive micromachined ultrasonic transducers (CMUTs) was presented, and an electromechanical equivalent circuit based on the theory reported was used to describe the behavior of the transducer [IEEE Trans. Ultrason. Ferroelectr. Freq. Control 49, 159-168 (2002)]. The distributed model is applied here to calculate the dynamic coupling factor k(w) of a lossless CMUT, based on a definition that involves the energies stored in a dynamic vibration cycle, and the results are compared with those obtained with a lumped model. A strong discrepancy is found between the two models as the bias voltage increases. The lumped model predicts an increasing dynamic k factor up to unity, whereas the distributed model predicts a more realistic saturation of this parameter to values substantially lower. It is demonstrated that the maximum value of k(w), corresponding to an operating point close to the diaphragm collapse, is 0.4 for a CMUT single cell with a circular membrane diaphragm and no parasitic capacitance (0.36 for a cell with a circular plate diaphragm). This means that the dynamic coupling factor of a CMUT is comparable to that of a piezoceramic plate oscillating in the thickness mode. Parasitic capacitance decreases the value of k(w), because it does not contribute to the energy conversion. The effective coupling factor k(eff) is also investigated, showing that this parameter coincides with k(w) within the lumped model approximation, but a quite different result is obtained if a computation is made with the more accurate distributed model. As a consequence, k(eff), which can be measured from the transducer electrical impedance, does not give a reliable value of the actual dynamic coupling factor.

  1. Electromechanical coupling factor of capacitive micromachined ultrasonic transducers

    NASA Astrophysics Data System (ADS)

    Caronti, Alessandro; Carotenuto, Riccardo; Pappalardo, Massimo

    2003-01-01

    Recently, a linear, analytical distributed model for capacitive micromachined ultrasonic transducers (CMUTs) was presented, and an electromechanical equivalent circuit based on the theory reported was used to describe the behavior of the transducer [IEEE Trans. Ultrason. Ferroelectr. Freq. Control 49, 159-168 (2002)]. The distributed model is applied here to calculate the dynamic coupling factor kw of a lossless CMUT, based on a definition that involves the energies stored in a dynamic vibration cycle, and the results are compared with those obtained with a lumped model. A strong discrepancy is found between the two models as the bias voltage increases. The lumped model predicts an increasing dynamic k factor up to unity, whereas the distributed model predicts a more realistic saturation of this parameter to values substantially lower. It is demonstrated that the maximum value of kw, corresponding to an operating point close to the diaphragm collapse, is 0.4 for a CMUT single cell with a circular membrane diaphragm and no parasitic capacitance (0.36 for a cell with a circular plate diaphragm). This means that the dynamic coupling factor of a CMUT is comparable to that of a piezoceramic plate oscillating in the thickness mode. Parasitic capacitance decreases the value of kw, because it does not contribute to the energy conversion. The effective coupling factor keff is also investigated, showing that this parameter coincides with kw within the lumped model approximation, but a quite different result is obtained if a computation is made with the more accurate distributed model. As a consequence, keff, which can be measured from the transducer electrical impedance, does not give a reliable value of the actual dynamic coupling factor.

  2. Microscopic Study of the Influence of Impurities on Interface Bonding.

    DTIC Science & Technology

    1985-01-25

    with different impurities (P,S) levels were specially made by Armco, Inc. In addition to these four alloys, commercial alloys including Armco’s Nitronic ...25 30 40 50 60 70 Percent Intergranular, % IG Figu re A. 10 Variation of K and plane stress Keff with IGA for the Fe-P-W specimens. 20 AIO 40 Fe-P-Mo...iIS- Ke f f q !m=- 0.218 35 E 30 - 30- ~m=-0. 145 25 20 25 30 40 50 60 70 Percent Intergranular, % IG Figurej A.9 Vriation of K and plane stress Keff

  3. Use of integral experiments in support to the validation of JEFF-3.2 nuclear data evaluation

    NASA Astrophysics Data System (ADS)

    Leclaire, Nicolas; Cochet, Bertrand; Jinaphanh, Alexis; Haeck, Wim

    2017-09-01

    For many years now, IRSN has developed its own Monte Carlo continuous energy capability, which allows testing various nuclear data libraries. In that prospect, a validation database of 1136 experiments was built from cases used for the validation of the APOLLO2-MORET 5 multigroup route of the CRISTAL V2.0 package. In this paper, the keff obtained for more than 200 benchmarks using the JEFF-3.1.1 and JEFF-3.2 libraries are compared to benchmark keff values and main discrepancies are analyzed regarding the neutron spectrum. Special attention is paid on benchmarks for which the results have been highly modified between both JEFF-3 versions.

  4. Spectroscopic investigation of phenolic groups ionization in the vipoxin neurotoxic phospholipase A 2: comparison with the X-ray structure in the region of the tyrosyl residues

    NASA Astrophysics Data System (ADS)

    Georgieva, Dessislava Nikolova; Genov, Nicolay; Rajashankar, Kanagalaghatta R.; Aleksiev, Boris; Betzel, Christian

    1998-12-01

    The neurotoxin vipoxin is the major lethal component of the venom of Vipera ammodites meridionalis, the most toxic snake in Europe. It is a complex between a toxic phospholipase A 2 (PLA 2) and a non-toxic protein inhibitor (Inh). Tyrosyl residues are involved in the catalytic site (Tyr 52 and 73) and in the substrate binding (Tyr 22). Spectroscopic studies demonstrated differences in the ionization behavior of the various phenolic hydroxyl groups in the toxic PLA 2. The tyrosyl side chains of the enzyme can be classified into three groups: (a) three phenolic hydroxyls are accessible to the solvent and titrate normally, with a p Keff=10.45; (b) three residues are partially 'buried' and participate in hydrogen bonds with neighboring functional groups. They titrate anomalously with a p Keff=12.17; (c) two tyrosines with a p Keff=13.23 are deeply 'buried' in the hydrophobic interior of PLA 2. They became accessible to the titrating agent only after alkaline denaturation of the protein molecule. The spectroscopic data are related to the X-ray structure of the vipoxin PLA 2. The refined model was investigated in the region of the tyrosyl side chains. The accessible surface area of each tyrosyl residue and each phenolic hydroxyl group was calculated. A good correlation between the spectrophotometric and the crystallographic data was observed. The ionization behavior of the phenolic groups is explained by peculiarities of the protein three-dimensional structure and the participation of tyrosines in the catalytic site hydrogen bond network. Attempts are made to assign the calculated p Keff values to individual residues. The high degree of 'exposure' on the protein surface of Tyr 22 and 75 is probably important for their function as parts of the substrate binding and pharmacological sites.

  5. The hybrid reactor project based on the straight field line mirror concept

    NASA Astrophysics Data System (ADS)

    Ågren, O.; Noack, K.; Moiseenko, V. E.; Hagnestâl, A.; Källne, J.; Anglart, H.

    2012-06-01

    The straight field line mirror (SFLM) concept is aiming towards a steady-state compact fusion neutron source. Besides the possibility for steady state operation for a year or more, the geometry is chosen to avoid high loads on materials and plasma facing components. A comparatively small fusion hybrid device with "semi-poor" plasma confinement (with a low fusion Q factor) may be developed for industrial transmutation and energy production from spent nuclear fuel. This opportunity arises from a large fission to fusion energy multiplication ratio, Qr = Pfis/Pfus>>1. The upper bound on Qr is primarily determined by geometry and reactor safety. For the SFLM, the upper bound is Qr≈150, corresponding to a neutron multiplicity of keff=0.97. Power production in a mirror hybrid is predicted for a substantially lower electron temperature than the requirement Te≈10 keV for a fusion reactor. Power production in the SFLM seems possible with Q≈0.15, which is 10 times lower than typically anticipated for hybrids (and 100 times smaller than required for a fusion reactor). This relaxes plasma confinement demands, and broadens the range for use of plasmas with supra-thermal ions in hybrid reactors. The SFLM concept is based on a mirror machine stabilized by qudrupolar magnetic fields and large expander tanks beyond the confinement region. The purpose of the expander tanks is to distribute axial plasma loss flow over a sufficiently large area so that the receiving plates can withstand the heat. Plasma stability is not relying on a plasma flow into the expander regions. With a suppressed plasma flow into the expander tanks, a possibility arise for higher electron temperature. A brief presentation will be given on basic theory for the SFLM with plasma stability and electron temperature issues, RF heating computations with sloshing ion formation, neutron transport computations with reactor safety margins and material load estimates, magnetic coil designs as well as a discussion on the implications of the geometry for possible diagnostics. Reactor safety issues are addressed and a vertical orientation of the device could assist passive coolant circulation. Specific attention is put to a device with a 25 m long confinement region and 40 cm plasma radius in the mid-plane. In an optimal case (keff = 0.97) with a fusion power of only 10 MW, such a device may be capable of producing a power of 1.5 GWth.

  6. Measurement and analysis of the mannitol partition coefficient in sucrose crystallization under simulated industrial conditions.

    PubMed

    Eggleston, Gillian; Yen, Jenny Wu Tiu; Alexander, Clay; Gober, Jessica

    2012-07-01

    Mannitol is a major deterioration product of Leuconstoc mesenteroides bacterial metabolism of sucrose and fructose from both sugarcane and sugar beet. The effect of crystallization conditions on the mannitol partition coefficient (K(eff)) between impure sucrose syrup and crystal has been investigated in a batch laboratory crystallizer and a batch pilot plant-scale vacuum pan. Laboratory crystallization was operated at 65.5°C (150°F), 60.0°C (140°F), and 51.7°C (125°F) with a 78.0 Brix (% refractometric dissolved solids) pure sucrose syrup containing 0%, 0.1%, 0.2%, 1.0%, 2.0%, 3.0%, and 10% (at 65.5°C only) mannitol on a Brix basis. Produced mother liquor and crystals were separated by centrifugation and their mannitol contents measured by ion chromatography with integrated pulsed amperometric detection (IC-IPAD). The extent of mannitol partitioning into the crystals depended strongly on the mannitol concentration in the feed syrup and, to a lesser extent, the crystallization temperature. At 65.5 and 60.0°C, the K(eff) varied from ~0.4% to 3.0% with 0.2% to 3.0% mannitol in the feed syrup, respectively. The mannitol K(eff) was lower than that reported for dextran (~9-10% K(eff)), another product of Leuconstoc deterioration, under similar sucrose crystal growth conditions. At 10% mannitol concentration in the syrup at 65.5°C, co-crystallization of mannitol with sucrose occurred and the crystal growth rate was greatly impeded. In both laboratory and pilot plant crystallizations (95.7% purity; 78.0 Brix; 65.5°C), mannitol tended to cause conglomerates to form, which became progressively worse with increased mannitol syrup concentration. At the 3% mannitol concentration, crystallization at both the laboratory and pilot plant scales was more difficult. Mannitol incorporation into the sucrose crystal results mostly from liquid syrup inclusions but adsorption onto the crystal surface may play a minor role at lower mannitol concentrations. Published by Elsevier Ltd.

  7. Variation of the subsidence parameters, effective thermal conductivity, and mantle dynamics

    NASA Astrophysics Data System (ADS)

    Adam, C.; King, S. D.; Vidal, V.; Rabinowicz, M.; Jalobeanu, A.; Yoshida, M.

    2015-09-01

    The subsidence of young seafloor is generally considered to be a passive phenomenon related to the conductive cooling of the lithosphere after its creation at mid-oceanic ridges. Recent alternative theories suggest that the mantle dynamics plays an important role in the structure and depth of the oceanic lithosphere. However, the link between mantle dynamics and seafloor subsidence has still to be quantitatively assessed. Here we provide a statistical study of the subsidence parameters (subsidence rate and ridge depth) for all the oceans. These parameters are retrieved through two independent methods, the positive outliers method, a classical method used in signal processing, and through the MiFil method. From the subsidence rate, we compute the effective thermal conductivity, keff, which ranges between 1 and 7 W m-1 K-1. We also model the mantle flow pattern from the S40RTS tomography model. The density anomalies derived from S40RTS are used to compute the instantaneous flow in a global 3D spherical geometry. We show that departures from the keff = 3 Wm-1K-1 standard value are systematically related to mantle processes and not to lithospheric structure. Regions characterized by keff > 3 Wm-1K-1 are associated with mantle uplifts (mantle plumes or other local anomalies). Regions characterized by keff < 3 Wm-1K-1 are related to large-scale mantle downwellings such as the Australia-Antarctic Discordance (AAD) or the return flow from the South Pacific Superswell to the East Pacific Rise. This demonstrates that mantle dynamics plays a major role in the shaping of the oceanic seafloor. In particular, the parameters generally considered to quantify the lithosphere structure, such as the thermal conductivity, are not only representative of this structure but also incorporate signals from the mantle convection occurring beneath the lithosphere. The dynamic topography computed from the S40RTS tomography model reproduces the subsidence pattern observed in the bathymetry. Overall we find a good correlation between the subsidence parameters derived from the bathymetry and the dynamic topography. This demonstrates that these parameters are strongly dependent on mantle dynamics.

  8. ENDF/B-VII.0 Data Testing Using 1,172 Critical Assemblies

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

    Plechaty, E F; Cullen, D E

    2007-10-01

    In order to test the ENDF/B-VII.0 neutron data library [1], 1,172 critical assemblies from [2] have been calculated using the Monte Carlo transport code TART [3]. TART's 'best' physics was used for all of these calculations; this included continuous energy cross sections, delayed neutrons in their spectrum that is slower than prompt neutrons, unresolved resonance region self-shielding, the thermal scattering (free atom for all materials plus thermal scattering law data S({alpha},{beta}) when available). In this first pass through the assemblies the objective was to 'quickly' test the validity of the ENDF/B-VII.0 data [1], the assembly models as defined in [2]more » and coded for use with TART, and TART's physics treatment [3] of these assemblies. With TART we have the option of running criticality problems until K-eff has been calculated to an acceptable input accuracy. In order to 'quickly' calculate all of these assemblies K-eff was calculated in each case to +/- 0.002. For these calculations the assemblies were divided into ten types based on fuel (mixed, Pu239, U233, U235) and median fission energy (Fast, Midi, Slow). A table is provided that shows a summary of these results. This is followed be details for every assembly, and statistical information about the distribution of K-eff for each type of assembly. After a review of these results to eliminate any obvious errors in ENDF/B data, assembly models, or TART physics, all assemblies will be run again to a higher precision. Only after this second run is finished will we have highly precise results. Until then the results presently here should only be interpreted as approximate values of K-eff with a standard deviation of +/- 0.002; for such a large number of assemblies we expected the results to be approximately normal, with a spread out to several times the standard deviation; see the calculated statistical distributions and their comparisons to a normal distribution.« less

  9. Simplified numerical approach for estimation of effective segregation coefficient at the melt/crystal interface

    NASA Astrophysics Data System (ADS)

    Prostomolotov, A. I.; Verezub, N. A.; Voloshin, A. E.

    2014-09-01

    A thermo-gravitational convection and impurity transfer in the melt were investigated using a simplified numerical model for Bridgman GaSb(Te) crystal growth in microgravity conditions. Simplifications were as follows: flat melt/crystal interface, fixed melt sizes and only lateral ampoule heating. Calculations were carried out by Ansys®Fluent® code employing a two-dimensional Navier-Stokes-Boussinesq and heat and mass transfer equations in a coordinate system moving with the melt/crystal interface. The parametric dependence of the effective segregation coefficient Keff at the melt/crystal interface was studied for various ampoule sizes and for microgravity conditions. For the uprising one-vortex flow, the resulting dependences were presented as Keff vs. Vmax-the maximum velocity value. These dependences were compared with the formulas by Burton-Prim-Slichter's, Ostrogorsky-Muller's, as well as with the semi-analytical solutions.

  10. Goal-based h-adaptivity of the 1-D diamond difference discrete ordinate method

    NASA Astrophysics Data System (ADS)

    Jeffers, R. S.; Kópházi, J.; Eaton, M. D.; Févotte, F.; Hülsemann, F.; Ragusa, J.

    2017-04-01

    The quantity of interest (QoI) associated with a solution of a partial differential equation (PDE) is not, in general, the solution itself, but a functional of the solution. Dual weighted residual (DWR) error estimators are one way of providing an estimate of the error in the QoI resulting from the discretisation of the PDE. This paper aims to provide an estimate of the error in the QoI due to the spatial discretisation, where the discretisation scheme being used is the diamond difference (DD) method in space and discrete ordinate (SN) method in angle. The QoI are reaction rates in detectors and the value of the eigenvalue (Keff) for 1-D fixed source and eigenvalue (Keff criticality) neutron transport problems respectively. Local values of the DWR over individual cells are used as error indicators for goal-based mesh refinement, which aims to give an optimal mesh for a given QoI.

  11. Integration of Porogen-Based Low-k Films: Influence of Capping Layer Thickness and Long Thermal Anneals on Low-k Damage and Reliability

    NASA Astrophysics Data System (ADS)

    De Roest, David; Vereecke, Bart; Huffman, Craig; Heylen, Nancy; Croes, Kristof; Arai, Hirofumi; Takamure, Noboru; Beynet, Julien; Sprey, Hessel; Matsushita, Kiyohiro; Kobayashi, Nobuyoshi; Verdonck, Patrick; Demuynck, Steven; Beyer, Gerald; Tokei, Zsolt; Struyf, Herbert

    2010-05-01

    This paper discusses integration aspects of a porous low-k film (k ˜2.45) cured with a broadband UV lamp. Different process splits are discussed which could contribute to avoid integration induced damage and improve reliability. The main factor contributing to a successful integration is the presence of a thick (protecting) cap layer partially remaining after chemical mechanical polishing (CMP), which leads to yielding structures with a keff of ˜2.6, a breakdown voltage of ˜6.9 MV/cm and time dependent dielectric breakdown (TDDB) lifetimes in the excess of 100 years. Long thermal anneals restore the k-value but degrade lifetime.

  12. Streptavidin Modified ZnO Film Bulk Acoustic Resonator for Detection of Tumor Marker Mucin 1

    NASA Astrophysics Data System (ADS)

    Zheng, Dan; Guo, Peng; Xiong, Juan; Wang, Shengfu

    2016-09-01

    A ZnO-based film bulk acoustic resonator has been fabricated using a magnetron sputtering technology, which was employed as a biosensor for detection of mucin 1. The resonant frequency of the thin-film bulk acoustic resonator was located near at 1503.3 MHz. The average electromechanical coupling factor {K}_{eff}^2 and quality factor Q were 2.39 % and 224, respectively. Using the specific binding system of avidin-biotin, the streptavidin was self-assembled on the top gold electrode as the sensitive layer to indirectly test the MUC1 molecules. The resonant frequency of the biosensor decreases in response to the mass loading in range of 20-500 nM. The sensor modified with the streptavidin exhibits a high sensitivity of 4642.6 Hz/nM and a good selectivity.

  13. Capillary-Driven Solute Transport and Precipitation in Porous Media during Dry-Out

    NASA Astrophysics Data System (ADS)

    Ott, Holger; Andrew, Matthew; Blunt, Martin; Snippe, Jeroen

    2014-05-01

    The injection of dry or under-saturated gases or supercritical (SC) fluids into water bearing formations might lead to a formation dry-out in the vicinity of the injection well. The dry-out is caused by the evaporation/dissolution of formation water into the injected fluid and the subsequent transport of dissolved water in the injected fluid away from the injection well. Dry-out results in precipitation from solutes of the formation brine and consequently leads to a reduction of the rock's pore space (porosity) and eventually to a reduction of permeability near the injection well, or even to the loss of injectivity. Recently evidence has been found that the complexity of the pore space and the respective capillary driven solute transport plays a key role. While no effective-permeability (Keff) reduction was observed in a single-porosity sandstone, multi porosity carbonate rocks responded to precipitation with a strong reduction of Keff. The reason for the different response of Keff to salt precipitation is suspected to be in the exact location of the precipitate (solid salt) in the pore space. In this study, we investigate dry-out and salt precipitation due to supercritical CO2 injection in single and multi-porosity systems under near well-bore conditions. We image fluid saturation changes by means of μCT scanning during desaturation. We are able to observe capillary driven transport of the brine phase and the respective transport of solutes on the rock's pore scale. Finally we have access to the precipitated solid-salt phase and their distribution. The results can proof the thought models behind permeability porosity relationships K(φ) for injectivity modeling. The topic and the mechanisms we show are of general interest for drying processes in porous material such as soils and paper.

  14. Heterogeneous flow in multi-layer joint networks and its influence on incipient karst generation

    NASA Astrophysics Data System (ADS)

    Wang, X.; Jourde, H.

    2017-12-01

    Various dissolution types (e.g. pipe, stripe and sheet karstic features) have been observed in fractured layered limestones. Yet, due to a large range of structural and hydraulic parameters play a role in the karstification process, the dissolution mechanism, occurring either along fractures or bedding planes, is difficult to quantify. In this study, we use numerical models to investigate the influence of these parameters on the generation of different types of incipient karst. Specifically, we focus on two parameters: the fracture intensity contrast between adjacent layers and the aperture ratio between bedding planes and joints (abed/ajoint). The DFN models were generated using a pseudo-genetic code that considers the stress shadow zone. Flow simulations were performed using a combined finite-volume finite-element simulator under practical boundary conditions. The flow channeling within the fracture networks was characterized by applying a multi-fractal technique. The rock block equivalent permeability (keff) was also calculated to quantify the change in bulk hydraulic properties when changing the selected structural and hydraulic parameters. The flow simulation results show that the abed/ajoint ratio has a first-order control on the heterogeneous distribution of flow in the multi-layer system and on the magnitude of equivalent permeability. When abed/ajoint < 0.1, flow in the system is highly localized and controlled by joints, and the keff is low; while, when abed/ajoint > 0.1, the bedding plane has more control and flow becomes more pervasive and uniform, and the keff is accordingly high. A simple model, accounting for the calculation of the heterogeneous distributions of Damköhler number associated with different aperture ratios, is proposed to predict what type of incipient karst tends to develop under the studied flow conditions.

  15. Face-by-face growth of sucrose crystals from aqueous solutions in the presence of raffinose—II: Growth morphology and segregation

    NASA Astrophysics Data System (ADS)

    Sgualdino, G.; Aquilano, D.; Pastero, L.; Vaccari, G.

    2007-10-01

    Raffinose segregation into sucrose crystals is experimentally determined along with the modifications of the quantitative sucrose growth morphology, which are in turn related to the different growth conditions. ( Craff, σ) morphodromes nicely represent the conflict between the supersaturation and the raffinose concentration in the solution on the growth morphology, while the overall segregation rate is nearly proportional to the linear overall crystal growth rate. Chernov and Burton-Prim-Slichter models, checked to fit our keff and ln(keff-1-1) coefficients as a function of the supersaturation and of the mean linear overall growth rate, do not allow to know whether the segregation occurs either by a process dominated by surface integration, or by additive transfer dominated by volume diffusion within the boundary layer. The distribution of segregated raffinose strictly depends on the { h k l} growth sectors and doped crystals contain deformed lattice zones, as it comes out from X-ray powder diagrams.

  16. Modeling the atmospheric chemistry of TICs

    NASA Astrophysics Data System (ADS)

    Henley, Michael V.; Burns, Douglas S.; Chynwat, Veeradej; Moore, William; Plitz, Angela; Rottmann, Shawn; Hearn, John

    2009-05-01

    An atmospheric chemistry model that describes the behavior and disposition of environmentally hazardous compounds discharged into the atmosphere was coupled with the transport and diffusion model, SCIPUFF. The atmospheric chemistry model was developed by reducing a detailed atmospheric chemistry mechanism to a simple empirical effective degradation rate term (keff) that is a function of important meteorological parameters such as solar flux, temperature, and cloud cover. Empirically derived keff functions that describe the degradation of target toxic industrial chemicals (TICs) were derived by statistically analyzing data generated from the detailed chemistry mechanism run over a wide range of (typical) atmospheric conditions. To assess and identify areas to improve the developed atmospheric chemistry model, sensitivity and uncertainty analyses were performed to (1) quantify the sensitivity of the model output (TIC concentrations) with respect to changes in the input parameters and (2) improve, where necessary, the quality of the input data based on sensitivity results. The model predictions were evaluated against experimental data. Chamber data were used to remove the complexities of dispersion in the atmosphere.

  17. Modeling of crack bridging in a unidirectional metal matrix composite

    NASA Technical Reports Server (NTRS)

    Ghosn, Louis J.; Kantzos, Pete; Telesman, Jack

    1992-01-01

    The effective fatigue crack driving force and crack opening profiles were determined analytically for fatigue tested unidirectional composite specimens exhibiting fiber bridging. The crack closure pressure due to bridging was modeled using two approaches: the fiber pressure model and the shear lag model. For both closure models, the Bueckner weight function method and the finite element method were used to calculate crack opening displacements and the crack driving force. The predicted near crack tip opening profile agreed well with the experimentally measured profiles for single edge notch SCS-6/Ti-15-3 metal matrix composite specimens. The numerically determined effective crack driving force, Delta K(eff), was calculated using both models to correlate the measure crack growth rate in the composite. The calculated Delta K(eff) from both models accounted for the crack bridging by showing a good agreement between the measured fatigue crack growth rates of the bridged composite and that of unreinforced, unbridged titanium matrix alloy specimens.

  18. Measurement and analysis of the mannitol partition coefficient in sucrose crystallization under simulated industrial conditions

    USDA-ARS?s Scientific Manuscript database

    Mannitol is a major deterioration product of Leuconstoc mesenteroides bacterial deterioration of both sugarcane and sugar beet. The effect of crystallization conditions on the mannitol partition coefficient (Keff) between impure sucrose syrup and crystal has been investigated in a batch laboratory c...

  19. Impact of nuclear data uncertainty on safety calculations for spent nuclear fuel geological disposal

    NASA Astrophysics Data System (ADS)

    Herrero, J. J.; Rochman, D.; Leray, O.; Vasiliev, A.; Pecchia, M.; Ferroukhi, H.; Caruso, S.

    2017-09-01

    In the design of a spent nuclear fuel disposal system, one necessary condition is to show that the configuration remains subcritical at time of emplacement but also during long periods covering up to 1,000,000 years. In the context of criticality safety applying burn-up credit, k-eff eigenvalue calculations are affected by nuclear data uncertainty mainly in the burnup calculations simulating reactor operation and in the criticality calculation for the disposal canister loaded with the spent fuel assemblies. The impact of nuclear data uncertainty should be included in the k-eff value estimation to enforce safety. Estimations of the uncertainty in the discharge compositions from the CASMO5 burn-up calculation phase are employed in the final MCNP6 criticality computations for the intact canister configuration; in between, SERPENT2 is employed to get the spent fuel composition along the decay periods. In this paper, nuclear data uncertainty was propagated by Monte Carlo sampling in the burn-up, decay and criticality calculation phases and representative values for fuel operated in a Swiss PWR plant will be presented as an estimation of its impact.

  20. Ingested and biomineralized magnetic material in the prey Neocapritermes opacus termite: FMR characterization

    NASA Astrophysics Data System (ADS)

    de Oliveira, J. F.; Alves, O. C.; Esquivel, D. M. S.; Wajnberg, E.

    2008-03-01

    The temperature dependence of Ferromagnetic Resonance spectra, from 5 K to 280 K, was used to study the magnetic material present in Neocapritermes opacus termite, the only prey of the Pachycondyla marginata ant. The analysis of the resonant field and peak-to-peak linewidth allowed estimating the particle diameters and the effective anisotropy energy density, KEFF, as a sum of the bulk and surface contributions. It allowed to magnetically distinguish the particles of termites as collected in field from those of termites after 3 days under a cellulose diet, introduced to eliminate ingested/digested material. The data also, suggest the presence of oriented magnetite nanoparticles with diameters of 11.6 ± 0.3 nm in termites as collected in field and (14.0 ± 0.4 nm) in that under a cellulose diet. Differences between their KEFF and its components are also observed. Two transitions are revealed in the resonant field temperature dependence, one at about 50 K that was associated to surface effects and the other at about 100 K attributed to the Verwey transition.

  1. Differential Scanning Calorimetric Study and Potential Model of the Binding of the Primary Water of Hydration to K-Hyaluronate

    NASA Astrophysics Data System (ADS)

    Whitson, K. B.; Marlowe, R. L.; Lukan, A. M.; Lee, S. A.; Anthony, L.; Rupprecht, A.

    1997-11-01

    DSC was performed on samples of K-hyaluronate (KHA) through a temperature range of 25-180^oC. A transition peak was observed which is due to the desorption of the primary water of hydration. The maximum position of the peak was observed to change with different scan rates. The average energy of activation, E_A, and enthalpy for desorption of the primary water of hydration was determined to be 0.62 and 0.17 eV per water molecule, respectively. Analysis of Mossbauer data(G. Albanese et al., Hyperfine Int.,) 95, 97 (1995) allowed us to determine the effective force constant, k_eff, of the water bound to KHA to be approximately 19.4 eV/nm^2. The parameters E_A, ΔH,and k_eff allow us to construct a potential model for the primary water of hydration of KHA. Comparison of these parameters with the same parameters for HA and DNA with different counterions reveal that the energy of activation is similar, as well as the enthalpy change.

  2. ATR LEU Fuel and Burnable Absorber Neutronics Performance Optimization by Fuel Meat Thickness Variation

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

    G. S. Chang

    2007-09-01

    The Advanced Test Reactor (ATR) is a high power density and high neutron flux research reactor operating in the United States. Powered with highly enriched uranium (HEU), the ATR has a maximum thermal power rating of 250 MWth. Because of the large test volumes located in high flux areas, the ATR is an ideal candidate for assessing the feasibility of converting an HEU driven reactor to a low-enriched core. The present work investigates the necessary modifications and evaluates the subsequent operating effects of this conversion. A detailed plate-by-plate MCNP ATR 1/8th core model was developed and validated for a fuelmore » cycle burnup comparison analysis. Using the current HEU U 235 enrichment of 93.0 % as a baseline, an analysis can be performed to determine the low-enriched uranium (LEU) density and U-235 enrichment required in the fuel meat to yield an equivalent K-eff between the HEU core and the LEU core versus effective full power days (EFPD). The MCNP ATR 1/8th core model will be used to optimize the U-235 loading in the LEU core, such that the differences in K-eff and heat flux profile between the HEU and LEU core can be minimized. The depletion methodology MCWO was used to calculate K-eff versus EFPDs in this paper. The MCWO-calculated results for the LEU cases with foil (U-10Mo) types demonstrated adequate excess reactivity such that the K-eff versus EFPDs plot is similar to the reference ATR HEU case. Each HEU fuel element contains 19 fuel plates with a fuel meat thickness of 0.508 mm. In this work, the proposed LEU (U-10Mo) core conversion case with a nominal fuel meat thickness of 0.508 mm and the same U-235 enrichment (15.5 wt%) can be used to optimize the radial heat flux profile by varying the fuel plate thickness from 0.254 to 0.457 mm at the inner 4 fuel plates (1-4) and outer 4 fuel plates (16-19). In addition, a 0.7g of burnable absorber Boron-10 was added in the inner and outer plates to reduce the initial excess reactivity, and the inner/outer heat flux more effectively. The optimized LEU relative radial fission heat flux profile is bounded by the reference ATR HEU case. However, to demonstrate that the LEU core fuel cycle performance can meet the Updated Final Safety Analysis Report (UFSAR) safety requirements, additional studies will be necessary to evaluate and compare safety parameters such as void reactivity and Doppler coefficients, control components worth (outer shim control cylinders, safety rods and regulating rod), and shutdown margins between the HEU and LEU cores.« less

  3. Role of CoFeB thickness in electric field controlled sub-100 nm sized magnetic tunnel junctions

    NASA Astrophysics Data System (ADS)

    Lourembam, James; Huang, Jiancheng; Lim, Sze Ter; Gerard, Ernult Franck

    2018-05-01

    We report a comprehensive study on the role of the free layer thickness (tF) in electric-field controlled nanoscale perpendicular magnetic tunnel junctions (MTJs), comprising of free layer structure Ta/Co40Fe40B20/MgO, by using dc magnetoresistance and ultra-short magnetization switching measurements. Focusing on MTJs that exhibits positive effective device anisotropy (Keff), we observe that both the voltage-controlled magnetic anisotropy (ξ) and voltage modulation of coercivity show strong dependence on tF. We found that ξ varies dramatically and unexpectedly from ˜-3 fJ/V-m to ˜-41 fJ/V-m with increasing tF. We discuss the possibilities of electric-field tuning of the effective surface anisotropy term, KS as well as an additional interfacial magnetoelastic anisotropy term, K3 that scales with 1 /tF2. Voltage pulse induced 180° magnetization reversal is also demonstrated in our MTJs. Unipolar switching and oscillatory function of switching probability vs. pulse duration can be observed at higher tF, and agrees well with the two key device parameters — Keff and ξ.

  4. Neutronics and Thermal Hydraulics Study for Using a Low-Enriched Uranium Core in the Advanced Test Reactor -- 2008 Final Report

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

    G. S. Chang; M. A. Lillo; R. G. Ambrosek

    2008-06-01

    The Advanced Test Reactor (ATR) is a high power density and high neutron flux research reactor operating in the United States. Powered with highly enriched uranium (HEU), the ATR has a maximum thermal power rating of 250 MWth. Because of the large test volumes located in high flux areas, the ATR is an ideal candidate for assessing the feasibility of converting an HEU driven reactor to a low-enriched core. The present work investigates the necessary modifications and evaluates the subsequent operating effects of this conversion. A detailed plate-by-plate MCNP ATR 1/8th core model was developed and validated for a fuelmore » cycle burnup comparison analysis. Using the current HEU U 235 enrichment of 93.0 % as a baseline, an analysis was performed to determine the low-enriched uranium (LEU) density and U-235 enrichment required in the fuel meat to yield an equivalent K-eff versus effective full power days (EFPDs) between the HEU and the LEU cores. The MCNP ATR 1/8th core model was used to optimize the U 235 loading in the LEU core, such that the differences in K-eff and heat flux profiles between the HEU and LEU cores were minimized. The depletion methodology MCWO was used to calculate K-eff versus EFPDs in this paper. The MCWO-calculated results for the LEU demonstrated adequate excess reactivity such that the K-eff versus EFPDs plot is similar to the ATR reference HEU case study. Each HEU fuel element contains 19 fuel plates with a fuel meat thickness of 0.508 mm (20 mil). In this work, the proposed LEU (U-10Mo) core conversion case with nominal fuel meat thickness of 0.330 mm (13 mil) and U-235 enrichment of 19.7 wt% is used to optimize the radial heat flux profile by varying the fuel meat thickness from 0.191 mm (7.0 mil) to 0.330 mm (13.0 mil) at the inner 4 fuel plates (1-4) and outer 4 fuel plates (16-19). A 0.8g of Boron-10, a burnable absorber, was added in the inner and outer plates to reduce the initial excess reactivity, and the peak to average ratio of the inner/outer heat flux more effectively. Because the B-10 (n,a) reaction will produce Helium-4 (He-4), which might degrade the LEU foil type fuel performance, an alternative absorber option is proposed. The proposed LEU case study will have 6.918 g of Cadmium (Cd) mixed with the LEU at the inner 4 fuel plates (1-4) and outer 4 fuel plates (16-19) as a burnable absorber to achieve peak to average ratios similar to those for the ATR reference HEU case study.« less

  5. ATR LEU fuel and burnable absorber neutronics performance optimization by fuel meat thickness variation

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

    Chang, G.S.

    2008-07-15

    The Advanced Test Reactor (ATR) is a high power density and high neutron flux research reactor operating in the United States. Powered with highly enriched uranium (HEU), the ATR has a maximum thermal power rating of 250 MWth. Because of the large test volumes located in high flux areas, the ATR is an ideal candidate for assessing the feasibility of converting an HEU driven reactor to a low-enriched core. The present work investigates the necessary modifications and evaluates the subsequent operating effects of this conversion. A detailed plate-by-plate MCNP ATR 1/8th core model was developed and validated for a fuelmore » cycle burnup comparison analysis. Using the current HEU U-235 enrichment of 93.0 % as a baseline, an analysis can be performed to determine the low-enriched uranium (LEU) density and U-235 enrichment required in the fuel meat to yield an equivalent K-eff between the HEU core th and the LEU core versus effective full power days (EFPD). The MCNP ATR 1/8th core model will be used to optimize the U-235 loading in the LEU core, such that the differences in K-eff and heat flux profile between the HEU and LEU core can be minimized. The depletion methodology MCWO was used to calculate K-eff versus EFPDs in this paper. The MCWO-calculated results for the LEU cases with foil (U-10Mo) types demonstrated adequate excess reactivity such that the K-eff versus EFPDs plot is similar to the reference ATR HEU case. Each HEU fuel element contains 19 fuel plates with a fuel meat thickness of 0.508 mm. In this work, the proposed LEU (U-10Mo) core conversion case with a nominal fuel meat thickness of 0.381 mm and the same U-235 enrichment (19.7 wt%) can be used to optimize the radial heat flux profile by varying the fuel meat thickness from 0.191 mm (7.5 mil) to 0.343 mm (13.5 mil) at the inner 4 fuel plates (1-4) and outer 4 fuel plates (16-19). In addition, 0.8g of a burnable absorber, Boron-10, was added in the inner and outer plates to reduce the initial excess reactivity, and the inner/outer heat flux more effectively. The optimized LEU relative radial fission heat flux profile is bounded by the reference ATR HEU case. However, to demonstrate that the LEU core fuel cycle performance can meet the Updated Final Safety Analysis Report (UFSAR) safety requirements, additional studies will be necessary to evaluate and compare safety parameters such as void reactivity and Doppler coefficients, control components worth (outer shim control cylinders, safety rods and regulating rod), and shutdown margins between the HEU and LEU cores. (author)« less

  6. Impact Damage and Erosion of Ceramics and Composites.

    DTIC Science & Technology

    1980-12-31

    local fracture toughness, Keff’ with crack length, a, was used to determine the fracture criticality. Specifically, the fracture toughness was chosen...A complete description of strength behaviors thus requires an experimental determination of the local toughness, One of us (A. V. Virkar) is currently...34Simulated Strength - Grain Size Study Using Glass- Glass Ceramic Composite System," submitted to Journal of Materials Science, (1979). -~_ 6 I ~ -_- 0

  7. Fatigue-Life Prediction Methodology Using Small-Crack Theory

    NASA Technical Reports Server (NTRS)

    Newmann, James C., Jr.; Phillips, Edward P.; Swain, M. H.

    1997-01-01

    This paper reviews the capabilities of a plasticity-induced crack-closure model to predict fatigue lives of metallic materials using 'small-crack theory' for various materials and loading conditions. Crack-tip constraint factors, to account for three-dimensional state-of-stress effects, were selected to correlate large-crack growth rate data as a function of the effective-stress-intensity factor range (delta K(eff)) under constant-amplitude loading. Some modifications to the delta k(eff)-rate relations were needed in the near-threshold regime to fit measured small-crack growth rate behavior and fatigue endurance limits. The model was then used to calculate small- and large-crack growth rates, and to predict total fatigue lives, for notched and un-notched specimens made of two aluminum alloys and a steel under constant-amplitude and spectrum loading. Fatigue lives were calculated using the crack-growth relations and microstructural features like those that initiated cracks for the aluminum alloys and steel for edge-notched specimens. An equivalent-initial-flaw-size concept was used to calculate fatigue lives in other cases. Results from the tests and analyses agreed well.

  8. Separation of Cs and Sr from LiCl-KCl eutectic salt via a zone-refining process for pyroprocessing waste salt minimization

    NASA Astrophysics Data System (ADS)

    Shim, Moonsoo; Choi, Ho-Gil; Choi, Jeong-Hun; Yi, Kyung-Woo; Lee, Jong-Hyeon

    2017-08-01

    The purification of a LiCl-KCl salt mixture was carried out by a zone-refining process. To improve the throughput of zone refining, three heaters were installed in the zone refiner. The zone-refining method was used to grow pure LiCl-KCl salt ingots from a LiCl-KCl-CsCl-SrCl2 salt mixture. The main investigated parameters were the heater speed and the number of passes. From each zone-refined salt ingot, samples were collected axially along the salt ingot and the concentrations of Sr and Cs were determined. Experimental results show that the Sr and Cs concentrations at the initial region of the ingot were low and increased to a maximum at the final freezing region of the salt ingot. Concentration results of the zone-refined salt were compared with theoretical results furnished by the proposed model to validate its predictions. The keff values for Sr and Cs were 0.55 and 0.47, respectively. The correlation between the salt composition and separation behavior was also investigated. The keff values of the Sr in LiCl-KCl-SrCl2 and the Cs in LiCl-KCl-CsCl were found to be 0.53 and 0.44, respectively, by fitting the experimental data into the proposed model.

  9. Use of integral experiments for the assessment of a new 235U IRSN-CEA evaluation

    NASA Astrophysics Data System (ADS)

    Ichou, Raphaëlle; Leclaire, Nicolas; Leal, Luiz; Haeck, Wim; Morillon, Benjamin; Romain, Pascal; Duarte, Helder

    2017-09-01

    The Working Party on International Nuclear Data Evaluation Co-operation (WPEC) subgroup 29 (SG 29) was established to investigate an issue with the 235U capture cross-section in the energy range from 0.1 to 2.25 keV, due to a possible overestimation of 10% or more. To improve the 235U capture crosssection, a new 235U evaluation has been proposed by the Institut de Radioprotection et de Sûreté Nucléaire (IRSN) and the CEA, mainly based on new time-of-flight 235U capture cross-section measurements and recent fission cross-section measurements performed at the n_TOF facility from CERN. IRSN and CEA Cadarache were in charge of the thermal to 2.25 keV energy range, whereas the CEA DIF was responsible of the high energy region. Integral experiments showing a strong 235U sensitivity are used to assess the new evaluation, using Monte-Carlo methods. The keff calculations were performed with the 5.D.1 beta version of the MORET 5 code, using the JEFF-3.2 library and the new 235U evaluation, as well as the JEFF-3.3T1 library in which the new 235U has been included. The benchmark selection allowed highlighting a significant improvement on keff due to the new 235U evaluation. The results of this data testing are presented here.

  10. Benchmark Evaluation of Start-Up and Zero-Power Measurements at the High-Temperature Engineering Test Reactor

    DOE PAGES

    Bess, John D.; Fujimoto, Nozomu

    2014-10-09

    Benchmark models were developed to evaluate six cold-critical and two warm-critical, zero-power measurements of the HTTR. Additional measurements of a fully-loaded subcritical configuration, core excess reactivity, shutdown margins, six isothermal temperature coefficients, and axial reaction-rate distributions were also evaluated as acceptable benchmark experiments. Insufficient information is publicly available to develop finely-detailed models of the HTTR as much of the design information is still proprietary. However, the uncertainties in the benchmark models are judged to be of sufficient magnitude to encompass any biases and bias uncertainties incurred through the simplification process used to develop the benchmark models. Dominant uncertainties in themore » experimental keff for all core configurations come from uncertainties in the impurity content of the various graphite blocks that comprise the HTTR. Monte Carlo calculations of keff are between approximately 0.9 % and 2.7 % greater than the benchmark values. Reevaluation of the HTTR models as additional information becomes available could improve the quality of this benchmark and possibly reduce the computational biases. High-quality characterization of graphite impurities would significantly improve the quality of the HTTR benchmark assessment. Simulation of the other reactor physics measurements are in good agreement with the benchmark experiment values. The complete benchmark evaluation details are available in the 2014 edition of the International Handbook of Evaluated Reactor Physics Benchmark Experiments.« less

  11. Effects of reservoir heterogeneity on scaling of effective mass transfer coefficient for solute transport

    NASA Astrophysics Data System (ADS)

    Leung, Juliana Y.; Srinivasan, Sanjay

    2016-09-01

    Modeling transport process at large scale requires proper scale-up of subsurface heterogeneity and an understanding of its interaction with the underlying transport mechanisms. A technique based on volume averaging is applied to quantitatively assess the scaling characteristics of effective mass transfer coefficient in heterogeneous reservoir models. The effective mass transfer coefficient represents the combined contribution from diffusion and dispersion to the transport of non-reactive solute particles within a fluid phase. Although treatment of transport problems with the volume averaging technique has been published in the past, application to geological systems exhibiting realistic spatial variability remains a challenge. Previously, the authors developed a new procedure where results from a fine-scale numerical flow simulation reflecting the full physics of the transport process albeit over a sub-volume of the reservoir are integrated with the volume averaging technique to provide effective description of transport properties. The procedure is extended such that spatial averaging is performed at the local-heterogeneity scale. In this paper, the transport of a passive (non-reactive) solute is simulated on multiple reservoir models exhibiting different patterns of heterogeneities, and the scaling behavior of effective mass transfer coefficient (Keff) is examined and compared. One such set of models exhibit power-law (fractal) characteristics, and the variability of dispersion and Keff with scale is in good agreement with analytical expressions described in the literature. This work offers an insight into the impacts of heterogeneity on the scaling of effective transport parameters. A key finding is that spatial heterogeneity models with similar univariate and bivariate statistics may exhibit different scaling characteristics because of the influence of higher order statistics. More mixing is observed in the channelized models with higher-order continuity. It reinforces the notion that the flow response is influenced by the higher-order statistical description of heterogeneity. An important implication is that when scaling-up transport response from lab-scale results to the field scale, it is necessary to account for the scale-up of heterogeneity. Since the characteristics of higher-order multivariate distributions and large-scale heterogeneity are typically not captured in small-scale experiments, a reservoir modeling framework that captures the uncertainty in heterogeneity description should be adopted.

  12. Validation of Cross Sections with Criticality Experiment and Reaction Rates: the Neptunium Case

    NASA Astrophysics Data System (ADS)

    Leong, L. S.; Tassan-Got, L.; Audouin, L.; Berthier, B.; Le Naour, C.; Stéphan, C.; Paradela, C.; Tarrío, D.; Duran, I.

    2014-04-01

    The 237Np neutron-induced fission cross section has been recently measured in a large energy range (from eV to GeV) at the n_TOF facility at CERN. When compared to previous measurements the n_TOF fission cross section appears to be higher by 5-7% beyond the fission threshold. To check the relevance of the n_TOF data, we considered a criticality experiment performed at Los Alamos with a 6 kg sphere of 237Np, surrounded by uranium highly enriched in 235U so as to approach criticality with fast neutrons. The multiplication factor keff of the calculation is in better agreement with the experiment when we replace the ENDF/B-VII.0 evaluation of the 237Np fission cross section by the n_TOF data. We also explored the hypothesis of deficiencies of the inelastic cross section in 235U which has been invoked by some authors to explain the deviation of 750 pcm. The large modification needed to reduce the deviation seems to be incompatible with existing inelastic cross section measurements. Also we show that the νbar of 237Np can hardly be incriminated because of the high accuracy of the existing data. Fission rate ratios or averaged fission cross sections measured in several fast neutron fields seem to give contradictory results on the validation of the 237Np cross section but at least one of the benchmark experiments, where the active deposits have been well calibrated for the number of atoms, favors the n_TOF data set. These outcomes support the hypothesis of a higher fission cross section of 237Np.

  13. Analysis of JSI TRIGA MARK II reactor physical parameters calculated with TRIPOLI and MCNP.

    PubMed

    Henry, R; Tiselj, I; Snoj, L

    2015-03-01

    New computational model of the JSI TRIGA Mark II research reactor was built for TRIPOLI computer code and compared with existing MCNP code model. The same modelling assumptions were used in order to check the differences of the mathematical models of both Monte Carlo codes. Differences between the TRIPOLI and MCNP predictions of keff were up to 100pcm. Further validation was performed with analyses of the normalized reaction rates and computations of kinetic parameters for various core configurations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. The effect of dipole-dipole interactions on coercivity, anisotropy constant, and blocking temperature of MnFe2O4 nanoparticles

    NASA Astrophysics Data System (ADS)

    Aslibeiki, B.; Kameli, P.; Salamati, H.

    2016-02-01

    Superparamagnetic manganese ferrite nanoparticles with mean size of = 6.5(±1.5) nm were synthesized through a solvothermal method using Tri-ethylene glycol as a solvent. The peak temperature of zero field cooled measurements of magnetization and AC magnetic susceptibility curves shifted toward higher temperatures by applying different pressures from 0 to 1 kbar and increasing the powders compaction. The frequency dependence of AC susceptibility measurements indicated the presence of weak dipole-dipole interactions between nanoparticles. By increasing the powders compaction and interactions strength, the coercive field (Hc) increased and squareness (Mr/Ms) decreased. The obtained effective anisotropy constant (Keff), by susceptibility measurements, was from 1.72 × 106 to 2.36 × 106 ergs/cm3 for pressure of 0 to 1 kbar. These values are larger than those obtained from hysteresis loops at 5 K (0.14 × 106 to 0.34 × 106 erg/cm3). Also, the Keff was two orders of magnitude greater than that of bulk MnFe2O4. Size, surface effects, and total energy barrier between equilibrium states were reported as the main causes of large anisotropy. Below 75 K, a signature of weak surface spin glass was observed. However, memory effect experiment indicated that there is no collective superspin glass state in the samples. This study suggests the role of powders compaction on properties of a magnetic nanoparticles system. Furthermore, the coercivity, the anisotropy constant, and the blocking temperature are affected by changing nanoparticles compaction.

  15. New evaluation parameter for wearable thermoelectric generators

    NASA Astrophysics Data System (ADS)

    Wijethunge, Dimuthu; Kim, Woochul

    2018-04-01

    Wearable devices constitute a key application area for thermoelectric devices. However, owing to new constraints in wearable applications, a few conventional device optimization techniques are not appropriate and material evaluation parameters, such as figure of merit (zT) and power factor (PF), tend to be inadequate. We illustrated the incompleteness of zT and PF by performing simulations and considering different thermoelectric materials. The results indicate a weak correlation between device performance and zT and PF. In this study, we propose a new evaluation parameter, zTwearable, which is better suited for wearable applications compared to conventional zT. Owing to size restrictions, gap filler based device optimization is extremely critical in wearable devices. With respect to the occasions in which gap fillers are used, expressions for power, effective thermal conductivity (keff), and optimum load electrical ratio (mopt) are derived. According to the new parameters, the thermal conductivity of the material has become much more critical now. The proposed new evaluation parameter, namely, zTwearable, is extremely useful in the selection of an appropriate thermoelectric material among various candidates prior to the commencement of the actual design process.

  16. Confidence Intervals from Realizations of Simulated Nuclear Data

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

    Younes, W.; Ratkiewicz, A.; Ressler, J. J.

    2017-09-28

    Various statistical techniques are discussed that can be used to assign a level of confidence in the prediction of models that depend on input data with known uncertainties and correlations. The particular techniques reviewed in this paper are: 1) random realizations of the input data using Monte-Carlo methods, 2) the construction of confidence intervals to assess the reliability of model predictions, and 3) resampling techniques to impose statistical constraints on the input data based on additional information. These techniques are illustrated with a calculation of the keff value, based on the 235U(n, f) and 239Pu (n, f) cross sections.

  17. Evaluation of the 239 Pu prompt fission neutron spectrum induced by neutrons of 500 keV and associated covariances

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

    Neudecker, D.; Talou, P.; Kawano, T.

    2015-08-01

    We present evaluations of the prompt fission neutron spectrum (PFNS) of (PU)-P-239 induced by 500 keV neutrons, and associated covariances. In a previous evaluation by Talon et al. (2010), surprisingly low evaluated uncertainties were obtained, partly due to simplifying assumptions in the quantification of uncertainties from experiment and model. Therefore, special emphasis is placed here on a thorough uncertainty quantification of experimental data and of the Los Alamos model predicted values entering the evaluation. In addition, the Los Alamos model was extended and an evaluation technique was employed that takes into account the qualitative differences between normalized model predicted valuesmore » and experimental shape data These improvements lead to changes in the evaluated PENS and overall larger evaluated uncertainties than in the previous work. However, these evaluated uncertainties are still smaller than those obtained in a statistical analysis using experimental information only, due to strong model correlations. Hence, suggestions to estimate model defect uncertainties are presented. which lead to more reasonable evaluated uncertainties. The calculated k(eff) of selected criticality benchmarks obtained with these new evaluations agree with each other within their uncertainties despite the different approaches to estimate model defect uncertainties. The k(eff) one standard deviations overlap with some of those obtained using ENDF/B-VILl, albeit their mean values are further away from unity. Spectral indexes for the Jezebel critical assembly calculated with the newly evaluated PFNS agree with the experimental data for selected (n,) and (n,f) reactions, and show improvements for highenergy threshold (n,2n) reactions compared to ENDF/B-VII.l. (C) 2015 Elsevier B.V. All rights reserved.« less

  18. Comparative study on neutron data in integral experiments of MYRRHA mockup critical cores in the VENUS-F reactor

    NASA Astrophysics Data System (ADS)

    Krása, Antonín; Kochetkov, Anatoly; Baeten, Peter; Vittiglio, Guido; Wagemans, Jan; Bécares, Vicente

    2017-09-01

    VENUS-F is a fast, zero-power reactor with 30% wt. metallic uranium fuel and solid lead as coolant simulator. It serves as a mockup of the MYRRHA reactor core. This paper describes integral experiments performed in two critical VENUS-F core configurations (with and without graphite reflector). Discrepancies between experiments and Monte Carlo calculations (MCNP5) of keff, fission rate spatial distribution and reactivity effects (lead void and fuel Doppler) depending on a nuclear data library used (JENDL-4.0, ENDF-B-VII.1, JEFF-3.1.2, 3.2, 3.3T2) are presented.

  19. Efflux of drugs and solutes from brain: the interactive roles of diffusional transcapillary transport, bulk flow and capillary transporters.

    PubMed

    Groothuis, Dennis R; Vavra, Michael W; Schlageter, Kurt E; Kang, Eric W-Y; Itskovich, Andrea C; Hertzler, Shannon; Allen, Cathleen V; Lipton, Howard L

    2007-01-01

    We examined the roles of diffusion, convection and capillary transporters in solute removal from extracellular space (ECS) of the brain. Radiolabeled solutes (eight with passive distribution and four with capillary or cell transporters) were injected into the brains of rats (n=497) and multiple-time point experiments measured the amount remaining in brain as a function of time. For passively distributed compounds, there was a relationship between lipid:water solubility and total brain efflux:diffusional efflux, which dominated when k(p), the transcapillary efflux rate constant, was >10(0) h(-1); when 10(-1)

  20. Electrical Properties of Low Temperature Sintering Step-Down Multilayer Piezoelectric Transformer

    NASA Astrophysics Data System (ADS)

    Yoo, Juhyun; Kim, Kookjin; Jeong, Yeongho

    2007-06-01

    The multilayer structured ceramic transformers were sintered at the low temperature of 940 °C and manufactured with the size of 27 × 27 × 2.2 mm3, respectively, using 0.07Pb(Mn1/3Nb2/3)O3-0.06Pb(Zn1/3Nb2/3)O3-0.87Pb(Zr0.48Ti0.52)O3 (A-type) and 0.07Pb(Mn1/3Nb2/3)O3-0.10Pb(Ni1/3Nb2/3)O3-0.83Pb(Zr0.48Ti0.52)O3 (B-type) composition ceramics. And then, their electrical properties were investigated according to the variations of frequency and load resistance. The voltage step-up ratio of the transformers showed the maximum values at the vicinity of 69 kHz. At the load resistance of 100 Ω, A-type and B-type piezoelectric transformers showed the temperature rises of about 21 °C at the output power of 15 and 18 W, respectively. At B-type transformer with high effective electromechanical coupling factor (keff) and high piezoelectric constant (d33), lower temperature increase was relatively appeared.

  1. Separation of CsCl and SrCl2 from a ternary CsCl-SrCl2-LiCl via a zone refining process for waste salt minimization of pyroprocessing

    NASA Astrophysics Data System (ADS)

    Shim, Moonsoo; Choi, Ho Gil; Yi, Kyung Woo; Hwang, Il Soon; Lee, Jong Hyeon

    2016-11-01

    The purification of LiCl salt mixture has traditionally been carried out by a melt crystallization process. To improve the throughput of zone refining, three heaters were installed in the zone refiner. The zone refining method was used to grow pure LiCl salt ingots from LiCl-CsCl-SrCl2 salt mixture. The main investigated parameters were the heater speed and the number of passes. A change in the LiCl crystal grain size was observed according to the horizontal direction. From each zone refined salt ingot, samples were collected horizontally. To analyze the concentrations of Sr and Cs, an inductively coupled plasma optical emission spectrometer and inductively coupled plasma mass spectrometer were used, respectively. The experimental results show that Sr and Cs concentrations at the initial region of the ingot were low and reached their peak at the final freezing region of the salt ingot. Concentration results of zone refined salt were compared with theoretical results yielded by the proposed model to validate its predictions. The keff of Sr and Cs were 0.13 and 0.11, respectively. The decontamination factors of Sr and Cs were 450 and 1650, respectively.

  2. The design of a multisource americium-beryllium (Am-Be) neutron irradiation facility using MCNP for the neutronic performance calculation.

    PubMed

    Sogbadji, R B M; Abrefah, R G; Nyarko, B J B; Akaho, E H K; Odoi, H C; Attakorah-Birinkorang, S

    2014-08-01

    The americium-beryllium neutron irradiation facility at the National Nuclear Research Institute (NNRI), Ghana, was re-designed with four 20 Ci sources using Monte Carlo N-Particle (MCNP) code to investigate the maximum amount of flux that is produced by the combined sources. The results were compared with a single source Am-Be irradiation facility. The main objective was to enable us to harness the maximum amount of flux for the optimization of neutron activation analysis and to enable smaller sample sized samples to be irradiated. Using MCNP for the design construction and neutronic performance calculation, it was realized that the single-source Am-Be design produced a thermal neutron flux of (1.8±0.0007)×10(6) n/cm(2)s and the four-source Am-Be design produced a thermal neutron flux of (5.4±0.0007)×10(6) n/cm(2)s which is a factor of 3.5 fold increase compared to the single-source Am-Be design. The criticality effective, k(eff), of the single-source and the four-source Am-Be designs were found to be 0.00115±0.0008 and 0.00143±0.0008, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Low-power lead-cooled fast reactor loaded with MOX-fuel

    NASA Astrophysics Data System (ADS)

    Sitdikov, E. R.; Terekhova, A. M.

    2017-01-01

    Fast reactor for the purpose of implementation of research, education of undergraduate and doctoral students in handling innovative fast reactors and training specialists for atomic research centers and nuclear power plants (BRUTs) was considered. Hard neutron spectrum achieved in the fast reactor with compact core and lead coolant. Possibility of prompt neutron runaway of the reactor is excluded due to the low reactivity margin which is less than the effective fraction of delayed neutrons. The possibility of using MOX fuel in the BRUTs reactor was examined. The effect of Keff growth connected with replacement of natural lead coolant to 208Pb coolant was evaluated. The calculations and reactor core model were performed using the Serpent Monte Carlo code.

  4. Using atomic layer deposited tungsten to increase thermal conductivity of a packed bed

    DOE PAGES

    Van Norman, Staci A.; Tringe, Joseph W.; Sain, John D.; ...

    2015-04-13

    This paper investigated the effective thermal conductivity (k eff) of packed-beds that contained porous particles with nanoscale tungsten (W) films of different thicknesses formed by atomic layer deposition (ALD). A continuous film on the particles is vital towards increasing k eff of the packed beds. For example, the keff of an alumina packed bed was increased by three times after an ~8-nm continuous W film with 20 cycles of W ALD, whereas k eff was decreased on a polymer packed bed with discontinuous, evenly dispersed W-islands due to nanoparticle scattering of phonons. For catalysts, understanding the thermal properties of thesemore » packed beds is essential for developing thermally conductive supports as alternatives to structured supports.« less

  5. An Approach for Validating Actinide and Fission Product Burnup Credit Criticality Safety Analyses-Isotopic Composition Predictions

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

    Radulescu, Georgeta; Gauld, Ian C; Ilas, Germina

    2011-01-01

    The expanded use of burnup credit in the United States (U.S.) for storage and transport casks, particularly in the acceptance of credit for fission products, has been constrained by the availability of experimental fission product data to support code validation. The U.S. Nuclear Regulatory Commission (NRC) staff has noted that the rationale for restricting the Interim Staff Guidance on burnup credit for storage and transportation casks (ISG-8) to actinide-only is based largely on the lack of clear, definitive experiments that can be used to estimate the bias and uncertainty for computational analyses associated with using burnup credit. To address themore » issues of burnup credit criticality validation, the NRC initiated a project with the Oak Ridge National Laboratory to (1) develop and establish a technically sound validation approach for commercial spent nuclear fuel (SNF) criticality safety evaluations based on best-available data and methods and (2) apply the approach for representative SNF storage and transport configurations/conditions to demonstrate its usage and applicability, as well as to provide reference bias results. The purpose of this paper is to describe the isotopic composition (depletion) validation approach and resulting observations and recommendations. Validation of the criticality calculations is addressed in a companion paper at this conference. For isotopic composition validation, the approach is to determine burnup-dependent bias and uncertainty in the effective neutron multiplication factor (keff) due to bias and uncertainty in isotopic predictions, via comparisons of isotopic composition predictions (calculated) and measured isotopic compositions from destructive radiochemical assay utilizing as much assay data as is available, and a best-estimate Monte Carlo based method. This paper (1) provides a detailed description of the burnup credit isotopic validation approach and its technical bases, (2) describes the application of the approach for representative pressurized water reactor and boiling water reactor safety analysis models to demonstrate its usage and applicability, (3) provides reference bias and uncertainty results based on a quality-assurance-controlled prerelease version of the Scale 6.1 code package and the ENDF/B-VII nuclear cross section data.« less

  6. Application of perturbation theory to lattice calculations based on method of cyclic characteristics

    NASA Astrophysics Data System (ADS)

    Assawaroongruengchot, Monchai

    Perturbation theory is a technique used for the estimation of changes in performance functionals, such as linear reaction rate ratio and eigenvalue affected by small variations in reactor core compositions. Here the algorithm of perturbation theory is developed for the multigroup integral neutron transport problems in 2D fuel assemblies with isotropic scattering. The integral transport equation is used in the perturbative formulation because it represents the interconnecting neutronic systems of the lattice assemblies via the tracking lines. When the integral neutron transport equation is used in the formulation, one needs to solve the resulting integral transport equations for the flux importance and generalized flux importance functions. The relationship between the generalized flux importance and generalized source importance functions is defined in order to transform the generalized flux importance transport equations into the integro-differential equations for the generalized adjoints. Next we develop the adjoint and generalized adjoint transport solution algorithms based on the method of cyclic characteristics (MOCC) in DRAGON code. In the MOCC method, the adjoint characteristics equations associated with a cyclic tracking line are formulated in such a way that a closed form for the adjoint angular function can be obtained. The MOCC method then requires only one cycle of scanning over the cyclic tracking lines in each spatial iteration. We also show that the source importance function by CP method is mathematically equivalent to the adjoint function by MOCC method. In order to speed up the MOCC solution algorithm, a group-reduction and group-splitting techniques based on the structure of the adjoint scattering matrix are implemented. A combined forward flux/adjoint function iteration scheme, based on the group-splitting technique and the common use of a large number of variables storing tracking-line data and exponential values, is proposed to reduce the computing time when both direct and adjoint solutions are required. A problem that arises for the generalized adjoint problem is that the direct use of the negative external generalized adjoint sources in the adjoint solution algorithm results in negative generalized adjoint functions. A coupled flux biasing/decontamination scheme is applied to make the generalized adjoint functions positive using the adjoint functions in such a way that it can be used for the multigroup rebalance technique. Next we consider the application of the perturbation theory to the reactor problems. Since the coolant void reactivity (CVR) is a important factor in reactor safety analysis, we have decided to select this parameter for optimization studies. We consider the optimization and adjoint sensitivity techniques for the adjustments of CVR at beginning of burnup cycle (BOC) and k eff at end of burnup cycle (EOC) for a 2D Advanced CANDU Reactor (ACR) lattice. The sensitivity coefficients are evaluated using the perturbation theory based on the integral transport equations. Three sets of parameters for CVR-BOC and keff-EOC adjustments are studied: (1) Dysprosium density in the central pin with Uranium enrichment in the outer fuel rings, (2) Dysprosium density and Uranium enrichment both in the central pin, and (3) the same parameters as in the first case but the objective is to obtain a negative checkerboard CVR at beginning of cycle (CBCVR-BOC). To approximate the sensitivity coefficient at EOC, we perform constant-power burnup/depletion calculations for 600 full power days (FPD) using a slightly perturbed nuclear library and the unperturbed neutron fluxes to estimate the variation of nuclide densities at EOC. Sensitivity analyses of CVR and eigenvalue are included in the study. In addition the optimization and adjoint sensitivity techniques are applied to the CBCVR-BOC and keff-EOC adjustment of the ACR lattices with Gadolinium in the central pin. Finally we apply these techniques to the CVR-BOC, CVR-EOC and keff-EOC adjustment of a CANDU lattice of which the burnup period is extended from 300 to 450 FPDs. The cases with the central pin containing either Dysprosium or Gadolinium in the natural Uranium are considered in our study. (Abstract shortened by UMI.)

  7. Exchange bias and perpendicular anisotropy study of ultrathin Pt-Co-Pt-IrMn multilayers sputtered on float glass

    NASA Astrophysics Data System (ADS)

    Laval, M.; Lüders, U.; Bobo, J. F.

    2007-09-01

    We have prepared ultrathin Pt-Co-Pt-IrMn polycrystalline multilayers on float-glass substrates by DC magnetron sputtering. We have determined the optimal set of thickness for both Pt layers, the Co layer and the IrMn biasing layer so that these samples exhibit at the same time out-of-plane magnetic anisotropy and exchange bias. Kerr microscopy domain structure imaging evidences an increase of nucleation rate accompanied with inhomogeneous magnetic behavior in the case of exchange-biased films compared to Pt-Co-Pt trilayers. Polar hysteresis loops are measured in obliquely applied magnetic field conditions, allowing us to determine both perpendicular anisotropy effective constant Keff and exchange-bias coupling JE, which are significantly different from the ones determined by standard switching field measurements.

  8. Benchmark On Sensitivity Calculation (Phase III)

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

    Ivanova, Tatiana; Laville, Cedric; Dyrda, James

    2012-01-01

    The sensitivities of the keff eigenvalue to neutron cross sections have become commonly used in similarity studies and as part of the validation algorithm for criticality safety assessments. To test calculations of the sensitivity coefficients, a benchmark study (Phase III) has been established by the OECD-NEA/WPNCS/EG UACSA (Expert Group on Uncertainty Analysis for Criticality Safety Assessment). This paper presents some sensitivity results generated by the benchmark participants using various computational tools based upon different computational methods: SCALE/TSUNAMI-3D and -1D, MONK, APOLLO2-MORET 5, DRAGON-SUSD3D and MMKKENO. The study demonstrates the performance of the tools. It also illustrates how model simplifications impactmore » the sensitivity results and demonstrates the importance of 'implicit' (self-shielding) sensitivities. This work has been a useful step towards verification of the existing and developed sensitivity analysis methods.« less

  9. Methodology of full-core Monte Carlo calculations with leakage parameter evaluations for benchmark critical experiment analysis

    NASA Astrophysics Data System (ADS)

    Sboev, A. G.; Ilyashenko, A. S.; Vetrova, O. A.

    1997-02-01

    The method of bucking evaluation, realized in the MOnte Carlo code MCS, is described. This method was applied for calculational analysis of well known light water experiments TRX-1 and TRX-2. The analysis of this comparison shows, that there is no coincidence between Monte Carlo calculations, obtained by different ways: the MCS calculations with given experimental bucklings; the MCS calculations with given bucklings evaluated on base of full core MCS direct simulations; the full core MCNP and MCS direct simulations; the MCNP and MCS calculations, where the results of cell calculations are corrected by the coefficients taking into the account the leakage from the core. Also the buckling values evaluated by full core MCS calculations have differed from experimental ones, especially in the case of TRX-1, when this difference has corresponded to 0.5 percent increase of Keff value.

  10. Benchmarking of HEU Mental Annuli Critical Assemblies with Internally Reflected Graphite Cylinder

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

    Xiaobo, Liu; Bess, John D.; Marshall, Margaret A.

    Three experimental configurations of critical assemblies, performed in 1963 at the Oak Ridge Critical Experiment Facility, which are assembled using three different diameter HEU annuli (15-9 inches, 15-7 inches and 13-7 inches) metal annuli with internally reflected graphite cylinder are evaluated and benchmarked. The experimental uncertainties which are 0.00055, 0.00055 and 0.00055 respectively, and biases to the detailed benchmark models which are -0.00179, -0.00189 and -0.00114 respectively, were determined, and the experimental benchmark keff results were obtained for both detailed and simplified model. The calculation results for both detailed and simplified models using MCNP6-1.0 and ENDF VII.1 agree well tomore » the benchmark experimental results with a difference of less than 0.2%. These are acceptable benchmark experiments for inclusion in the ICSBEP Handbook.« less

  11. Studies of PuF sub 6 and transplutonic materials' critical properties for space high power nuclear pumped lasers

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

    Gu, A.G.; Miller, M.S.

    1991-01-01

    All space missions require a reliable, compact source of energy. This paper describes preliminary neutronics studies of pocket'' reactor concepts employing PuF{sub 6} and transplutonic materials as fuels for space high power/energy Nuclear Pumped Lasers (NPLs). Previous research has studied NPL reactor concepts with thin fuel layers, aerosol fuels and gaseous UF{sub 6}. The total reactor volumes for compact reactors with these types of fuels typically range from 3 m{sup 3} to 50 m{sup 3}. By employing PuF{sub 6} and transplutonic fuels at the same low densities, a calculated value for Keff of 1.2 has been achieved for conditions ofmore » 900 K and 5 atm, with total reactor volumes of 1.5 m{sup 3} for PuF{sub 6}, 0.51 m{sup 3} for Am-242m, 0.58 m{sup 3} for Cm-245 and 0.63 m{sup 3} for Cf-249.« less

  12. Giant perpendicular exchange bias with antiferromagnetic MnN

    NASA Astrophysics Data System (ADS)

    Zilske, P.; Graulich, D.; Dunz, M.; Meinert, M.

    2017-05-01

    We investigated an out-of-plane exchange bias system that is based on the antiferromagnet MnN. Polycrystalline, highly textured film stacks of Ta/MnN/CoFeB/MgO/Ta were grown on SiOx by (reactive) magnetron sputtering and studied by x-ray diffraction and Kerr magnetometry. Nontrivial modifications of the exchange bias and the perpendicular magnetic anisotropy were observed as functions of both film thicknesses and field cooling temperatures. In optimized film stacks, a giant perpendicular exchange bias of 3600 Oe and a coercive field of 350 Oe were observed at room temperature. The effective interfacial exchange energy is estimated to be Jeff = 0.24 mJ/m2 and the effective uniaxial anisotropy constant of the antiferromagnet is Keff = 24 kJ/m3. The maximum effective perpendicular anisotropy field of the CoFeB layer is Hani = 3400 Oe. These values are larger than any previously reported values. These results possibly open a route to magnetically stable, exchange biased perpendicularly magnetized spin valves.

  13. Neutronics calculation of RTP core

    NASA Astrophysics Data System (ADS)

    Rabir, Mohamad Hairie B.; Zin, Muhammad Rawi B. Mohamed; Karim, Julia Bt. Abdul; Bayar, Abi Muttaqin B. Jalal; Usang, Mark Dennis Anak; Mustafa, Muhammad Khairul Ariff B.; Hamzah, Na'im Syauqi B.; Said, Norfarizan Bt. Mohd; Jalil, Muhammad Husamuddin B.

    2017-01-01

    Reactor calculation and simulation are significantly important to ensure safety and better utilization of a research reactor. The Malaysian's PUSPATI TRIGA Reactor (RTP) achieved initial criticality on June 28, 1982. The reactor is designed to effectively implement the various fields of basic nuclear research, manpower training, and production of radioisotopes. Since early 90s, neutronics modelling were used as part of its routine in-core fuel management activities. The are several computer codes have been used in RTP since then, based on 1D neutron diffusion, 2D neutron diffusion and 3D Monte Carlo neutron transport method. This paper describes current progress and overview on neutronics modelling development in RTP. Several important parameters were analysed such as keff, reactivity, neutron flux, power distribution and fission product build-up for the latest core configuration. The developed core neutronics model was validated by means of comparison with experimental and measurement data. Along with the RTP core model, the calculation procedure also developed to establish better prediction capability of RTP's behaviour.

  14. Compact D-D Neutron Source-Driven Subcritical Multiplier and Beam-Shaping Assembly for Boron Neutron Capture Therapy

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

    Francesco Ganda; Jasmina Vujic; Ehud Greenspan

    2010-12-01

    This work assesses the feasibility of using a small, safe, and inexpensive keff 0.98 subcritical fission assembly [subcritical neutron multiplier (SCM)] to amplify the treatment neutron beam intensity attainable from a compact deuterium-deuterium (D-D) fusion neutron source delivering [approximately]1012 n/s. The objective is to reduce the treatment time for deep-seated brain tumors to [approximately]1 h. The paper describes the optimal SCM design and two optimal beam-shaping assemblies (BSAs) - one designed to maximize the dose rate and the other designed to maximize the total dose that can be delivered to a deep-seated tumor. The neutron beam intensity amplification achieved withmore » the optimized SCM and BSA results in an increase in the treatment dose rate by a factor of 18: from 0.56 Gy/h without the SCM to 10.1 Gy/h. The entire SCM is encased in an aluminum structure. The total amount of 20% enriched uranium required for the SCM is 8.5 kg, and the cost (not including fabrication) is estimated to be less than $60,000. The SCM power level is estimated at 400 W when driven by a 1012 n/s D-D neutron source. This translates into consumption of only [approximately]0.6% of the initially loaded 235U atoms during 50 years of continuous operation and implies that the SCM could operate continuously for the entire lifetime of the facility without refueling. Cooling the SCM does not pose a challenge; it may be accomplished by natural circulation as the maximum heat flux is only 0.034 W/cm2.« less

  15. Older Siblings’ Contributions to Young Child’s Cognitive Skills

    PubMed Central

    Dai, Xianhua; Heckman, James J.

    2014-01-01

    This work finds that older siblings as well as early parenting influence young children’s cognitive skills directly or indirectly, for example, Mathematics, and English. Our findings challenge a pervasive view in the economical literatures that early parenting play a dominant role in explaining child development. In economics, early environmental conditions are important to demonstrate the evolution of adolescent and adult cognitive skills (Knudsen, Heckman, Cameron, and Shonkoff, 2006; Cunha and Heckman, 2007), and it establishes causal impacts of early parental inputs and other environmental factors on cognitive and non-cognitive skills (Heckman, Stixrud, and Urzua, 2006; Borghans, Duckworth, Heckman, and Weel, 2006; Cunha, Heckman, and Schennach, 2010). Early parenting as well as older siblings should explain a diverse array of academic and social outcomes, for example, Mathematics, English, maritage and pregnancy. In fact, older siblings’ characteristics are as important, if not more important, than parenting for child development. Our analysis addresses the problems of measurement error, imperfect proxies, and reverse causality that plague conventional approach in psychology. We find that older brother contributes much more than older sister to child’s mathematical achievement, while older sister contributes much more to child’s english achievement. Our evidence is consistent with psychology literature, for example, Hetherington (1988), Jenkins (1992), Zukow-Goldring (1995), Marshall, Garcia-Coll, Marx, McCartney, Keffe, and Rub (1997), Maynard (2002), and Brody Ge, Kim, Murry, Simons, Gibbons, Gerrard, and Conger (2003) for siblings’ direct contributions to child development, Bronfenbrenner (1997), East (1998), Whiteman and Buchanan (2002), and Brody, Ge, Kim, Murry, Simons, Gibbons, Gerrard, and Conger (2003) for siblings’s indirect contributions, and Reiss, Neiderhiser, Hetherington, and Plomin (2000), Feinberg and Hetherington (2001), Kowal, Kramer, Krull, and Crick (2002) for parental differential treatment. PMID:25309016

  16. Older Siblings' Contributions to Young Child's Cognitive Skills.

    PubMed

    Dai, Xianhua; Heckman, James J

    2013-09-01

    This work finds that older siblings as well as early parenting influence young children's cognitive skills directly or indirectly, for example, Mathematics, and English. Our findings challenge a pervasive view in the economical literatures that early parenting play a dominant role in explaining child development. In economics, early environmental conditions are important to demonstrate the evolution of adolescent and adult cognitive skills (Knudsen, Heckman, Cameron, and Shonkoff, 2006; Cunha and Heckman, 2007), and it establishes causal impacts of early parental inputs and other environmental factors on cognitive and non-cognitive skills (Heckman, Stixrud, and Urzua, 2006; Borghans, Duckworth, Heckman, and Weel, 2006; Cunha, Heckman, and Schennach, 2010). Early parenting as well as older siblings should explain a diverse array of academic and social outcomes, for example, Mathematics, English, maritage and pregnancy. In fact, older siblings' characteristics are as important, if not more important, than parenting for child development. Our analysis addresses the problems of measurement error, imperfect proxies, and reverse causality that plague conventional approach in psychology. We find that older brother contributes much more than older sister to child's mathematical achievement, while older sister contributes much more to child's english achievement. Our evidence is consistent with psychology literature, for example, Hetherington (1988), Jenkins (1992), Zukow-Goldring (1995), Marshall, Garcia-Coll, Marx, McCartney, Keffe, and Rub (1997), Maynard (2002), and Brody Ge, Kim, Murry, Simons, Gibbons, Gerrard, and Conger (2003) for siblings' direct contributions to child development, Bronfenbrenner (1997), East (1998), Whiteman and Buchanan (2002), and Brody, Ge, Kim, Murry, Simons, Gibbons, Gerrard, and Conger (2003) for siblings's indirect contributions, and Reiss, Neiderhiser, Hetherington, and Plomin (2000), Feinberg and Hetherington (2001), Kowal, Kramer, Krull, and Crick (2002) for parental differential treatment.

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

    Wahanani, Nursinta Adi, E-mail: sintaadi@batan.go.id; Natsir, Khairina, E-mail: sintaadi@batan.go.id; Hartini, Entin, E-mail: sintaadi@batan.go.id

    Data processing software packages such as VSOP and MCNPX are softwares that has been scientifically proven and complete. The result of VSOP and MCNPX are huge and complex text files. In the analyze process, user need additional processing like Microsoft Excel to show informative result. This research develop an user interface software for output of VSOP and MCNPX. VSOP program output is used to support neutronic analysis and MCNPX program output is used to support burn-up analysis. Software development using iterative development methods which allow for revision and addition of features according to user needs. Processing time with this softwaremore » 500 times faster than with conventional methods using Microsoft Excel. PYTHON is used as a programming language, because Python is available for all major operating systems: Windows, Linux/Unix, OS/2, Mac, Amiga, among others. Values that support neutronic analysis are k-eff, burn-up and mass Pu{sup 239} and Pu{sup 241}. Burn-up analysis used the mass inventory values of actinide (Thorium, Plutonium, Neptunium and Uranium). Values are visualized in graphical shape to support analysis.« less

  18. Size-dependent magnetic anisotropy of PEG coated Fe3O4 nanoparticles; comparing two magnetization methods

    NASA Astrophysics Data System (ADS)

    Nayek, C.; Manna, K.; Imam, A. A.; Alqasrawi, A. Y.; Obaidat, I. M.

    2018-02-01

    Understanding the size dependent magnetic anisotropy of iron oxide nanoparticles is essential for the successful application of these nanoparticles in several technological and medical fields. PEG-coated iron oxide (Fe3O4) nanoparticles with core diameters of 12 nm, 15 nm, and 16 nm were synthesized by the usual co-precipitation method. The morphology and structure of the nanoparticles were investigated using transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), and X-ray diffraction (XRD). Magnetic measurements were conducted using a SQUID. The effective magnetic anisotropy was calculated using two methods from the magnetization measurements. In the first method the zero-field-cooled magnetization versus temperature measurements were used at several applied magnetic fields. In the second method we used the temperature-dependent coercivity curves obtained from the zero-field-cooled magnetization versus magnetic field hysteresis loops. The role of the applied magnetic field on the effective magnetic anisotropy, calculated form the zero-field-cooled magnetization versus temperature measurements, was revealed. The size dependence of the effective magnetic anisotropy constant Keff obtained by the two methods are compared and discussed.

  19. Microstructure and characterization of W-type hexaferrite Ba1-xLaxFe22+Fe163+O27 prepared by solid state method

    NASA Astrophysics Data System (ADS)

    Tang, Jin; Liu, Xiansong; Mehmood Ur Rehman, Khalid; Li, Dan; Li, Mingling; Yang, Yujie

    2018-04-01

    We report a successful preparation of Ba1-xLaxFe22+Fe163+O27 (x = 0.00-0.10) W-type hexagonal ferrites by standard ceramic method in a reduced oxygen atmosphere. In this work, the effect of the substitution La3+ rare-earth ions for Ba2+ ions on the structural and magnetic properties of the prepared samples have been studied. The phase identification of magnetic powders was performed by X-ray diffraction. The results of XRD show that the single phase was observed in the W-type ferrites with different La content. The SEM micrographs showed that the ferrites have formed the hexagonal structure. The magnetic properties of the samples were metric by a vibrating sample magnetometer. The coercivity (Hc) of the particles decreases with the increase of La content(x), while the saturation magnetization (Ms) of the particles first increases with x from 0 to 0.05, and then begins to decrease when x continues to increase. The monotonic dependence of the magnetic anisotropy field Ha and coercivity Hc on the La3+ doping amount is found to be mainly dominated by the competition between Ms and Keff.

  20. Bidirectional associations in multiplication memory: conditions of negative and positive transfer.

    PubMed

    Campbell, Jamie I D; Robert, Nicole D

    2008-05-01

    A variety of experimental evidence indicates that the memory representation for multiplication facts (e.g., 6 x 9 = 54) incorporates bidirectional links with a forward association from factors to product and a reverse association from product to factors. Surprisingly, the authors did not find evidence in Experiment 1 of facilitative transfer-of-practice from multiplication (6 x 9 = ?) to factoring (54 = ? x ?); in fact, multiplication practice produced item-specific interference with factoring. Similarly, the authors found no evidence in Experiment 2 that repetition of specific factoring problems (54 = ? x ?) facilitated performance of corresponding multiplication problems (6 x 9 = ?). In Experiment 3, participants practiced both multiplication and factoring and presented facilitative transfer in both directions. Thus, bidirectional facilitation occurred if both operations were practiced, but interference occurred when only one operation was practiced. We propose that this seemingly paradoxical behavior occurs because it is adaptive for the bidirectional retrieval structure to retain operational flexibility in the context of practicing both operations, whereas it is adaptive to specialize the memory representation for the practiced operation (i.e., factoring or multiplication) when only one operation is practiced.

  1. Using agent-based modeling to study multiple risk factors and multiple health outcomes at multiple levels.

    PubMed

    Yang, Yong

    2017-11-01

    Most health studies focus on one health outcome and examine the influence of one or multiple risk factors. However, in reality, various pathways, interactions, and associations exist not only between risk factors and health outcomes but also among the risk factors and among health outcomes. The advance of system science methods, Big Data, and accumulated knowledge allows us to examine how multiple risk factors influence multiple health outcomes at multiple levels (termed a 3M study). Using the study of neighborhood environment and health as an example, I elaborate on the significance of 3M studies. 3M studies may lead to a significantly deeper understanding of the dynamic interactions among risk factors and outcomes and could help us design better interventions that may be of particular relevance for upstream interventions. Agent-based modeling (ABM) is a promising method in the 3M study, although its potentials are far from being fully explored. Future challenges include the gap of epidemiologic knowledge and evidence, lack of empirical data sources, and the technical challenges of ABM. © 2017 New York Academy of Sciences.

  2. Is Hypovitaminosis D One of the Environmental Risk Factors for Multiple Sclerosis?

    ERIC Educational Resources Information Center

    Pierrot-Deseilligny, Charles; Souberbielle, Jean-Claude

    2010-01-01

    The role of hypovitaminosis D as a possible risk factor for multiple sclerosis is reviewed. First, it is emphasized that hypovitaminosis D could be only one of the risk factors for multiple sclerosis and that numerous other environmental and genetic risk factors appear to interact and combine to trigger the disease. Secondly, the classical…

  3. Unscaled Bayes factors for multiple hypothesis testing in microarray experiments.

    PubMed

    Bertolino, Francesco; Cabras, Stefano; Castellanos, Maria Eugenia; Racugno, Walter

    2015-12-01

    Multiple hypothesis testing collects a series of techniques usually based on p-values as a summary of the available evidence from many statistical tests. In hypothesis testing, under a Bayesian perspective, the evidence for a specified hypothesis against an alternative, conditionally on data, is given by the Bayes factor. In this study, we approach multiple hypothesis testing based on both Bayes factors and p-values, regarding multiple hypothesis testing as a multiple model selection problem. To obtain the Bayes factors we assume default priors that are typically improper. In this case, the Bayes factor is usually undetermined due to the ratio of prior pseudo-constants. We show that ignoring prior pseudo-constants leads to unscaled Bayes factor which do not invalidate the inferential procedure in multiple hypothesis testing, because they are used within a comparative scheme. In fact, using partial information from the p-values, we are able to approximate the sampling null distribution of the unscaled Bayes factor and use it within Efron's multiple testing procedure. The simulation study suggests that under normal sampling model and even with small sample sizes, our approach provides false positive and false negative proportions that are less than other common multiple hypothesis testing approaches based only on p-values. The proposed procedure is illustrated in two simulation studies, and the advantages of its use are showed in the analysis of two microarray experiments. © The Author(s) 2011.

  4. Child Maltreatment Among Singletons and Multiple Births in Japan: A Population-Based Study.

    PubMed

    Yokoyama, Yoshie; Oda, Terumi; Nagai, Noriyo; Sugimoto, Masako; Mizukami, Kenji

    2015-12-01

    The occurrence of multiple births has been recognized as a risk factor for child maltreatment. However, few population-based studies have examined the relationship between multiple births and child maltreatment. This study aimed to evaluate the degree of risk of child maltreatment among singletons and multiple births in Japan and to identify factors associated with increased risk. Using population-based data, we analyzed the database of records on child maltreatment and medical checkups for infants aged 1.5 years filed at Nishinomiya City Public Health Center between April 2007 and March 2011. To protect personal information, the data were transferred to anonymized electronic files for analysis. After adjusting by logistic regression for each associated factor and gestation number, multiples themselves were not associated with the risk of child maltreatment. However, compared with singletons, multiples had a significantly higher rate of risk factors for child maltreatment, including low birth weight and neural abnormality. Moreover, compared with mothers of singleton, mothers of twins had a significantly higher rate of poor health, which is a risk factor of child maltreatment. Multiples were not associated with the risk of child maltreatment. However, compared with singletons, multiples and their mothers had a significantly higher rate of risk factors of child maltreatment.

  5. Multiplication factor versus regression analysis in stature estimation from hand and foot dimensions.

    PubMed

    Krishan, Kewal; Kanchan, Tanuj; Sharma, Abhilasha

    2012-05-01

    Estimation of stature is an important parameter in identification of human remains in forensic examinations. The present study is aimed to compare the reliability and accuracy of stature estimation and to demonstrate the variability in estimated stature and actual stature using multiplication factor and regression analysis methods. The study is based on a sample of 246 subjects (123 males and 123 females) from North India aged between 17 and 20 years. Four anthropometric measurements; hand length, hand breadth, foot length and foot breadth taken on the left side in each subject were included in the study. Stature was measured using standard anthropometric techniques. Multiplication factors were calculated and linear regression models were derived for estimation of stature from hand and foot dimensions. Derived multiplication factors and regression formula were applied to the hand and foot measurements in the study sample. The estimated stature from the multiplication factors and regression analysis was compared with the actual stature to find the error in estimated stature. The results indicate that the range of error in estimation of stature from regression analysis method is less than that of multiplication factor method thus, confirming that the regression analysis method is better than multiplication factor analysis in stature estimation. Copyright © 2012 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  6. Vernier effect-based multiplication of the Sagnac beating frequency in ring laser gyroscope sensors

    NASA Astrophysics Data System (ADS)

    Adib, George A.; Sabry, Yasser M.; Khalil, Diaa

    2018-02-01

    A multiplication method of the Sagnac effect scale factor in ring laser gyroscopes is presented based on the Vernier effect of a dual-coupler passive ring resonator coupled to the active ring. The multiplication occurs when the two rings have comparable lengths or integer multiples and their scale factors have opposite signs. In this case, and when the rings have similar areas, the scale factor is multiplied by ratio of their length to their length difference. The scale factor of the presented configuration is derived analytically and the lock-in effect is analyzed. The principle is demonstrated using optical fiber rings and semiconductor optical amplifier as gain medium. A scale factor multiplication by about 175 is experimentally measured, demonstrating larger than two orders of magnitude enhancement in the Sagnac effect scale factor for the first time in literature, up to the authors' knowledge.

  7. Competition of wormholes during the evolution of cave passages

    NASA Astrophysics Data System (ADS)

    Gabrovsek, Franci; Dreybrodt, Wolfgang

    2017-04-01

    Reactive fronts in two-dimensional plane parallel fractures, with constant head difference between input and output and with diffusion controlled first order reaction rates R = keff ṡ (Ceq - C), where keff = k ṡ (1 + ka/6D)-1, are instable to infinitesimal perturbations in fracture aperture width (1), causing spontaneous fingering of the reactive front resulting in the formation of wormholes. C is the actual concentration and Ceq the equilibrium concentration, a, is the actual aperture width of the fracture , and D the constant of molecular diffusion. Fingering happens also in plane-parallel rough fractures where it is triggered by the existence of statistically more favorable pathways. The same behavior is observed in rectangular two-dimensional networks of "one-dimensional" smooth fractures used in modeling the evolution of caves in soluble rock (2). Here the formation of caves can be regarded as the evolution of wormholes along the two-dimensional network. Once fingering has been triggered, either by instability or by roughness, many small fingers compete with each other and only a few survive. Here we investigate the competition between two seeded fingers in initially homogeneous fracture networks with identical aperture width of all fractures and also in inhomogeneous ones where the aperture widths are distributed log normally. In both cases our modeling reveals the rules of competition: By instability one of the fingers grows faster than its competitor therefore penetrating somewhat deeper. As a consequence the hydraulic head at its tip is higher than that close to the tip of the shorter finger. Therefore the fractures connecting the tip regions of both fingers carry flow from the deep finger to the tip region of its competitor. This cross-flow is replaced by increasing inflow of aggressive solution into the input of the winner, enhancing further dissolution and growth. On the other hand the cross-flow increases the head at the tip of the losing finger, and consequently decreases inflow of aggressive solution into it, thus inhibiting its further evolution. This mechanism supports further growth of the winner (wormhole) and stops the growth of its competitor. Similar competition happens in the case of several fingers competing. In any case we observe flow from the winning fingers to the loosing ones. The communication between the competitors is always established by cross flow between its tip regions. We will present various scenarios of wormhole formation, which demonstrate details of the competition of fingers arising from either the reactive instability or from the statistical distribution of fracture aperture widths. In conclusion we find that the initiation of wormholes results either from instability or from the statistical distribution of favorable pathways. Once growth of fingers has been initiated the evolution of the wormhole patterns becomes deterministic. (1) Szymczak, P., and A.J.C. Ladd (2011), The initial stages of cave formation: Beyond the one-dimensional paradigm, Earth Planet. Sci. Lett. 301, 424-432 (2) Dreybrodt, W., Gabrovšek, F., Romanov, D.(2005) Processes of Speleogenesis: A Modeling Approach. ZRC Publishing, Karst Research Institute at ZRC SAZU, Ljubljana

  8. Analysis of clinical risk factors associated with the prognosis of severe multiple-trauma patients with acute lung injury.

    PubMed

    Wu, Junsong; Sheng, Lei; Wang, Shenhua; Li, Qiang; Zhang, Mao; Xu, Shaowen; Gan, Jianxin

    2012-09-01

    Several clinical risk factors have been reported to be associated with the prognosis of acute lung injury (ALI). However, these studies have included a general trauma patient population, without singling out the severely injured multiple-trauma patient population. To identify the potential risk factors that could affect the prognosis of ALI in multiple-trauma patients and investigate the prognostic effects of certain risk factors among different patient subpopulations. In this retrospective cohort study, severely injured multiple-trauma patients with early onset of ALI from several trauma centers were studied. Potential risk factors affecting the prognosis of ALI were examined by univariate and multivariate logistic analyses. There were 609 multiple-trauma patients with ALI admitted to the emergency department and emergency intensive care unit during the study period. The nine risk factors that affected prognosis, as indicated by the unadjusted odds ratios with 95% confidence intervals, were the APACHE II (Acute Physiology and Chronic Health Evaluation II) score, duration of trauma, age, gastrointestinal hemorrhage, pulmonary contusion, disseminated intravascular coagulation (DIC), multiple blood transfusions in 6 h, Injury Severity Score (ISS), and aspiration of gastric contents. Specific risk factors also affected different patient subpopulations in different ways. Patients older than 65 years and with multiple (> 10 units) blood transfusions in the early stage after multiple trauma were found to be independent risk factors associated with deterioration of ALI. The other factors studied, including pulmonary contusion, APACHE II score ≥ 20, ISS ≥ 16, gastrointestinal hemorrhage, and aspiration of gastric contents, may predict the unfavorable prognosis of ALI in the early stage of trauma, with their effects attenuating in the later stage. Duration of trauma ≥ 1 h and the presence of DIC may also indicate unfavorable prognosis during the entire treatment period. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

  9. Assessment of Risk Factors of Intrauterine Adhesions in Patients With Induced Abortion and the Curative Effect of Hysteroscopic Surgery.

    PubMed

    Mo, Xiaoliang; Qin, Guirong; Zhou, Zhoulin; Jiang, Xiaoli

    2017-10-03

    To explore the risk factors for intrauterine adhesions in patients with artificial abortion and clinical efficacy of hysteroscopic dissection. 1500 patients undergoing artificial abortion between January 2014 and June 2015 were enrolled into this study. The patients were divided into two groups with or without intrauterine adhesions. Univariate and Multiple logistic regression were conducted to assess the effects of multiple factors on the development of intrauterine adhesions following induced abortion. The incidence rate for intrauterine adhesions following induced abortion is 17.0%. Univariate showed that preoperative inflammation, multiple pregnancies and suction evacuation time are the influence risk factors of intrauterine adhesions. Multiple logistic regression demonstrates that multiple pregnancies, high intrauterine negative pressure, and long suction evacuation time are independent risk factors for the development of intrauterine adhesions following induced abortion. Additionally, intrauterine adhesions were observed in 105 mild, 80 moderate, and 70 severe cases. The cure rates for these three categories of intrauterine adhesions by hysteroscopic surgery were 100.0%, 93.8%, and 85.7%, respectively. Multiple pregnancies, high negative pressure suction evacuation and long suction evacuation time are independent risk factors for the development of intrauterine adhesions following induced abortions. Hysteroscopic surgery substantially improves the clinical outcomes of intrauterine adhesions.

  10. A Multiple Indicators Multiple Cause (MIMIC) model of respiratory health and household factors in Chinese children: the seven Northeastern cities (SNEC) study.

    PubMed

    Dong, Guang-Hui; Qian, Zhengmin; Fu, Qiang; Wang, Jing; Trevathan, Edwin; Ma, Wenjun; Liu, Miao-Miao; Wang, Da; Ren, Wan-Hui; Ong, Kee-Hean; Ferguson, Tekeda Freeman; Riley, Erin; Simckes, Maayan

    2014-01-01

    In China, with the rapid economic development and improvement of living standards over the past few decades, the household living environment has shifted dramatically. The aim of the present study is to assess the impact of home environment factors on respiratory symptoms and asthma in Chinese children. Investigators analyzed data collected in the 25 districts from the seven Northeastern cities to examine health effects on respiratory symptoms and asthma in 31,049 children aged 2-14 years. Factor analysis was used to reduce 33 children's lifestyle and household variables to six new 'factor' variables. The multiple indicators multiple causes approach was used to examine the relationship between indoor air pollution and respiratory health status, controlling for covariates. Factor analyses generated six factor variables of potential household risk factors from an original list of 33 variables. The respiratory symptoms and asthma were significantly associated with the recent home renovation factor (estimate = 0.076, p < 0.001), pet ownership factor (estimate = 0.095, p < 0.001), environmental tobacco smoke (ETS) exposure factor (estimate = 0.181, p < 0.001) and PVC-flooring factor (estimate = 0.031, p = 0.007). Home ventilation factor was not related to any respiratory condition (estimate = 0.028, p = 0.074). Independent respiratory health effects existed for multiple household environmental factors recent home renovation, pet ownership, ETS, and PVC-flooring.

  11. A quantitative model of application slow-down in multi-resource shared systems

    DOE PAGES

    Lim, Seung-Hwan; Kim, Youngjae

    2016-12-26

    Scheduling multiple jobs onto a platform enhances system utilization by sharing resources. The benefits from higher resource utilization include reduced cost to construct, operate, and maintain a system, which often include energy consumption. Maximizing these benefits comes at a price-resource contention among jobs increases job completion time. In this study, we analyze slow-downs of jobs due to contention for multiple resources in a system; referred to as dilation factor. We observe that multiple-resource contention creates non-linear dilation factors of jobs. From this observation, we establish a general quantitative model for dilation factors of jobs in multi-resource systems. A job ismore » characterized by a vector-valued loading statistics and dilation factors of a job set are given by a quadratic function of their loading vectors. We demonstrate how to systematically characterize a job, maintain the data structure to calculate the dilation factor (loading matrix), and calculate the dilation factor of each job. We validate the accuracy of the model with multiple processes running on a native Linux server, virtualized servers, and with multiple MapReduce workloads co-scheduled in a cluster. Evaluation with measured data shows that the D-factor model has an error margin of less than 16%. We extended the D-factor model to capture the slow-down of applications when multiple identical resources exist such as multi-core environments and multi-disks environments. Finally, validation results of the extended D-factor model with HPC checkpoint applications on the parallel file systems show that D-factor accurately captures the slow down of concurrent applications in such environments.« less

  12. A quantitative model of application slow-down in multi-resource shared systems

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

    Lim, Seung-Hwan; Kim, Youngjae

    Scheduling multiple jobs onto a platform enhances system utilization by sharing resources. The benefits from higher resource utilization include reduced cost to construct, operate, and maintain a system, which often include energy consumption. Maximizing these benefits comes at a price-resource contention among jobs increases job completion time. In this study, we analyze slow-downs of jobs due to contention for multiple resources in a system; referred to as dilation factor. We observe that multiple-resource contention creates non-linear dilation factors of jobs. From this observation, we establish a general quantitative model for dilation factors of jobs in multi-resource systems. A job ismore » characterized by a vector-valued loading statistics and dilation factors of a job set are given by a quadratic function of their loading vectors. We demonstrate how to systematically characterize a job, maintain the data structure to calculate the dilation factor (loading matrix), and calculate the dilation factor of each job. We validate the accuracy of the model with multiple processes running on a native Linux server, virtualized servers, and with multiple MapReduce workloads co-scheduled in a cluster. Evaluation with measured data shows that the D-factor model has an error margin of less than 16%. We extended the D-factor model to capture the slow-down of applications when multiple identical resources exist such as multi-core environments and multi-disks environments. Finally, validation results of the extended D-factor model with HPC checkpoint applications on the parallel file systems show that D-factor accurately captures the slow down of concurrent applications in such environments.« less

  13. Evaluation of Neutron Poison Materials for DOE SNF Disposal Systems

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

    Vinson, D.W.; Caskey, G.R. Jr.; Sindelar, R.L.

    1998-09-01

    Aluminum-based spent nuclear fuel (Al-SNF) from foreign and domestic research reactors is being consolidated at the Savannah River Site (SRS) for ultimate disposal in the Mined Geologic Disposal System (MGDS). Most of the aluminum-based fuel material contains highly enriched uranium (HEU) (more than 20 percent 235U), which challenges the preclusion of criticality events for disposal periods exceeding 10,000 years. Recent criticality analyses have shown that the addition of neutron absorbing materials (poisons) is needed in waste packages containing DOE SNF canisters fully loaded with Al-SNF under flooded and degraded configurations to demonstrate compliance with the requirement that Keff less thanmore » 0.95. Compatibility of poison matrix materials and the Al-SNF, including their relative degradation rate and solubility, are important to maintain criticality control. An assessment of the viability of poison and matrix materials has been conducted, and an experimental corrosion program has been initiated to provide data on degradation rates of poison and matrix materials and Al-SNF materials under repository relevant vapor and aqueous environments. Initial testing includes Al6061, Type 316L stainless steel, and A516Gr55 in synthesized J-13 water vapor at 50 degrees C, 100 degrees C, and 200 degrees C and in condensate water vapor at 100 degrees C. Preliminary results are presented herein.« less

  14. Benchmark Evaluation of HTR-PROTEUS Pebble Bed Experimental Program

    DOE PAGES

    Bess, John D.; Montierth, Leland; Köberl, Oliver; ...

    2014-10-09

    Benchmark models were developed to evaluate 11 critical core configurations of the HTR-PROTEUS pebble bed experimental program. Various additional reactor physics measurements were performed as part of this program; currently only a total of 37 absorber rod worth measurements have been evaluated as acceptable benchmark experiments for Cores 4, 9, and 10. Dominant uncertainties in the experimental keff for all core configurations come from uncertainties in the ²³⁵U enrichment of the fuel, impurities in the moderator pebbles, and the density and impurity content of the radial reflector. Calculations of k eff with MCNP5 and ENDF/B-VII.0 neutron nuclear data aremore » greater than the benchmark values but within 1% and also within the 3σ uncertainty, except for Core 4, which is the only randomly packed pebble configuration. Repeated calculations of k eff with MCNP6.1 and ENDF/B-VII.1 are lower than the benchmark values and within 1% (~3σ) except for Cores 5 and 9, which calculate lower than the benchmark eigenvalues within 4σ. The primary difference between the two nuclear data libraries is the adjustment of the absorption cross section of graphite. Simulations of the absorber rod worth measurements are within 3σ of the benchmark experiment values. The complete benchmark evaluation details are available in the 2014 edition of the International Handbook of Evaluated Reactor Physics Benchmark Experiments.« less

  15. Magnetic and optical properties of Zn2+ ion substituted barium hexaferrites

    NASA Astrophysics Data System (ADS)

    Baykal, A.; Auwal, I. A.; Güner, S.; Sözeri, H.

    2017-05-01

    Ba1-xZnxFe12O19 (0.0≤x≤0.3) hexaferrites were produced via sol-gel auto combustion technique. XRD patterns show that all the samples are single-phase M-type barium hexaferrite (BaM). Scanning electron microscopy (SEM) revealed that grains have a size range of 0.5-2 μm. The magnetic hysteresis (σ-H) loops revealed the ferromagnetic nature of NPs. The average crystallite sizes were calculated by applying Scherrer equation on the base of XRD powder patterns of all samples and found to be in the range of 16.78-48.34 nm. In particular, Ba1-xZnxFe12O19 (0.0≤x≤0.3) hexaferrites have suitable magnetic characteristics (saturation magnetization in a range of 63.00-67.70 emu/g and coercive field in a range of 822-1275 Oe) for magnetic recording and permanent magnets. Effective crystalline anisotropy constants (Keff) are between 4.20×105 and 4.84×105 Erg/g. Magnetic moment increased by the substitution of non-magnetic Zn2+ ions. The anisotropy field (Ha) or intrinsic coercivity values above 13255 Oe reveals that all samples are magnetically hard materials. Tauc plots were drawn to specify the direct optical energy band gap (Eg) of NPs. The Eg values are in a narrow range between 1.69 eV and 1.76 eV.

  16. Comparative Study on Various Geometrical Core Design of 300 MWth Gas Cooled Fast Reactor with UN-PuN Fuel Longlife without Refuelling

    NASA Astrophysics Data System (ADS)

    Dewi Syarifah, Ratna; Su'ud, Zaki; Basar, Khairul; Irwanto, Dwi

    2017-07-01

    Nuclear power has progressive improvement in the operating performance of exiting reactors and ensuring economic competitiveness of nuclear electricity around the world. The GFR use gas coolant and fast neutron spectrum. This research use helium coolant which has low neutron moderation, chemical inert and single phase. Comparative study on various geometrical core design for modular GFR with UN-PuN fuel long life without refuelling has been done. The calculation use SRAC2006 code both PIJ calculation and CITATION calculation. The data libraries use JENDL 4.0. The variation of fuel fraction is 40% until 65%. In this research, we varied the geometry of core reactor to find the optimum geometry design. The variation of the geometry design is balance cylinder; it means that the diameter active core (D) same with height active core (H). Second, pancake cylinder (D>H) and third, tall cylinder (D

  17. Experimental Studies on the Effect of Enhanced Thermal Conductivity of SiC+Water Nanofluid in the Performance of Small Scale Solar Parabolic Dish Receiver

    NASA Astrophysics Data System (ADS)

    Rajendran, D. R.; Sundaram, E. Ganapathy; Jawahar, P.

    In this experimental study, exergy efficiencies of water and SiC+water nanofluid, prepared from 50nm particle size and 1% of volume fraction were compared based on the effect of thermal conductivities by a dish reflector receiver system. The average temperature difference between the receiver walls and heat transfer fluids have been studied to understand the thermal performance of the system with respect to the important properties of thermal conductivities and specific heat capacities. The enhanced thermal conductivity of 0.800115W/mK with the Keff/Kb ratio of 1.1759 was determined by the Koo and Kleinstreuer correlation which is considering both the Maxwell correlation and Brownian motion. The attained higher average exergy efficiencies for water and SiC+water nanofluid are 21.08% and 37.06.%, respectively with the enhanced nanofluid exergy efficiency of 75.80% than that of water at the flow rate of 0.5lpm. The result also shows that the system with SiC+water nanofluid produced higher exergy efficiency, because the rates of energy and exergy carried by the nanofluid are 0.2378kW and 0.7593kW higher than that of water for all the flow rates except at 0.2lpm, due to the enhanced thermal conductivity of the nanofluid.

  18. Individual and social determinants of multiple chronic disease behavioral risk factors among youth.

    PubMed

    Alamian, Arsham; Paradis, Gilles

    2012-03-22

    Behavioral risk factors are known to co-occur among youth, and to increase risks of chronic diseases morbidity and mortality later in life. However, little is known about determinants of multiple chronic disease behavioral risk factors, particularly among youth. Previous studies have been cross-sectional and carried out without a sound theoretical framework. Using longitudinal data (n = 1135) from Cycle 4 (2000-2001), Cycle 5 (2002-2003) and Cycle 6 (2004-2005) of the National Longitudinal Survey of Children and Youth, a nationally representative sample of Canadian children who are followed biennially, the present study examines the influence of a set of conceptually-related individual/social distal variables (variables situated at an intermediate distance from behaviors), and individual/social ultimate variables (variables situated at an utmost distance from behaviors) on the rate of occurrence of multiple behavioral risk factors (physical inactivity, sedentary behavior, tobacco smoking, alcohol drinking, and high body mass index) in a sample of children aged 10-11 years at baseline. Multiple behavioral risk factors were assessed using a multiple risk factor score. All statistical analyses were performed using SAS, version 9.1, and SUDAAN, version 9.01. Multivariate longitudinal Poisson models showed that social distal variables including parental/peer smoking and peer drinking (Log-likelihood ratio (LLR) = 187.86, degrees of freedom (DF) = 8, p < .001), as well as individual distal variables including low self-esteem (LLR = 76.94, DF = 4, p < .001) increased the rate of occurrence of multiple behavioral risk factors. Individual ultimate variables including age, sex, and anxiety (LLR = 9.34, DF = 3, p < .05), as well as social ultimate variables including family socioeconomic status, and family structure (LLR = 10.93, DF = 5, p = .05) contributed minimally to the rate of co-occurrence of behavioral risk factors. The results suggest targeting individual/social distal variables in prevention programs of multiple chronic disease behavioral risk factors among youth.

  19. Predictors of postoperative outcomes of cubital tunnel syndrome treatments using multiple logistic regression analysis.

    PubMed

    Suzuki, Taku; Iwamoto, Takuji; Shizu, Kanae; Suzuki, Katsuji; Yamada, Harumoto; Sato, Kazuki

    2017-05-01

    This retrospective study was designed to investigate prognostic factors for postoperative outcomes for cubital tunnel syndrome (CubTS) using multiple logistic regression analysis with a large number of patients. Eighty-three patients with CubTS who underwent surgeries were enrolled. The following potential prognostic factors for disease severity were selected according to previous reports: sex, age, type of surgery, disease duration, body mass index, cervical lesion, presence of diabetes mellitus, Workers' Compensation status, preoperative severity, and preoperative electrodiagnostic testing. Postoperative severity of disease was assessed 2 years after surgery by Messina's criteria which is an outcome measure specifically for CubTS. Bivariate analysis was performed to select candidate prognostic factors for multiple linear regression analyses. Multiple logistic regression analysis was conducted to identify the association between postoperative severity and selected prognostic factors. Both bivariate and multiple linear regression analysis revealed only preoperative severity as an independent risk factor for poor prognosis, while other factors did not show any significant association. Although conflicting results exist regarding prognosis of CubTS, this study supports evidence from previous studies and concludes early surgical intervention portends the most favorable prognosis. Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

  20. NON-MENDELIAN ETIOLOGIC FACTORS IN NEUROPSYCHIATRIC ILLNESS: PLEIOTROPY, EPIGENETICS, AND CONVERGENCE

    PubMed Central

    Deutsch, Curtis K; McIlvane, William J

    2013-01-01

    The target article by Charney on behavior genetics/genomics discusses how numerous molecular factors can inform heritability estimations and genetic association studies. These factors find application in the search for genes for behavioral phenotypes, including neuropsychiatric disorders. We elaborate upon how single causal factors can generate multiple phenotypes, and discuss how multiple causal factors may converge on common neurodevelopmental mechanisms. PMID:23095384

  1. Demographic, genetic, and environmental factors that modify disease course.

    PubMed

    Marrie, Ruth Ann

    2011-05-01

    As with susceptibility to disease, it is likely that multiple factors interact to influence the phenotype of multiple sclerosis and long-term disease outcomes. Such factors may include genetic factors, socioeconomic status, comorbid diseases, and health behaviors, as well as environmental exposures. An improved understanding of the influence of these factors on disease course may reap several benefits, such as improved prognostication, allowing us to tailor disease management with respect to intensity of disease-modifying therapies and changes in specific health behaviors, in the broad context of coexisting health issues. Such information can facilitate appropriately adjusted comparisons within and between populations. Elucidation of these factors will require careful study of well-characterized populations in which the roles of multiple factors are considered simultaneously. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Characteristics and correlates of coping with multiple sclerosis: a systematic review.

    PubMed

    Keramat Kar, Maryam; Whitehead, Lisa; Smith, Catherine M

    2017-10-10

    The purpose of this systematic review was to examine coping strategies that people with multiple sclerosis use, and to identify factors that influence their coping pattern. This systematic review followed the Joanna Briggs Institute guidelines for synthesizing descriptive quantitative research. The following databases were searched from the inception of databases until December 2016: Ovid (Medline, Embase, CINAHL, and PsycINFO), Science Direct, Web of Science, and Scopus. Manual search was also conducted from the reference lists of retrieved articles. Findings related to the patterns of coping with multiple sclerosis and factors influencing coping with multiple sclerosis were extracted and synthesized. The search of the database yielded 455 articles. After excluding duplicates (n = 341) and studies that did not meet the inclusion criteria (n = 27), 71 studies were included in the full-text review. Following the full-text, a further 21 studies were excluded. Quality appraisal of 50 studies was completed, and 38 studies were included in the review. Synthesis of findings indicated that people with multiple sclerosis use emotional and avoidance coping strategies more than other types of coping, particularly in the early stages of the disease. In comparison to the general population, people with multiple sclerosis were less likely to use active coping strategies and used more avoidance and emotional coping strategies. The pattern of coping with multiple sclerosis was associated with individual, clinical and psychological factors including gender, educational level, clinical course, mood and mental status, attitude, personality traits, and religious beliefs. The findings of this review suggest that considering individual or disease-related factors could help healthcare professionals in identifying those less likely to adapt to multiple sclerosis. This information could also be used to provide client-centered rehabilitation for people living with multiple sclerosis based on their individual responses and perceptions for coping. Implications for rehabilitation Engagement in coping with multiple sclerosis has been associated with individual factors and neuropsychological functions. Considering individual and disease-related factors would allow healthcare professionals to provide more tailored interventions to maintain and master coping with multiple sclerosis. People living with multiple sclerosis should be empowered to appraise and manage ability to cope based on the contextual evidence (individual and clinical condition). Rehabilitation services should move beyond physical management incorporating behavioral aspects for better functioning in living with multiple sclerosis.

  3. Evaluation of the comprehensive palatability of Japanese sake paired with dishes by multiple regression analysis based on subdomains.

    PubMed

    Nakamura, Ryo; Nakano, Kumiko; Tamura, Hiroyasu; Mizunuma, Masaki; Fushiki, Tohru; Hirata, Dai

    2017-08-01

    Many factors contribute to palatability. In order to evaluate the palatability of Japanese alcohol sake paired with certain dishes by integrating multiple factors, here we applied an evaluation method previously reported for palatability of cheese by multiple regression analysis based on 3 subdomain factors (rewarding, cultural, and informational). We asked 94 Japanese participants/subjects to evaluate the palatability of sake (1st evaluation/E1 for the first cup, 2nd/E2 and 3rd/E3 for the palatability with aftertaste/afterglow of certain dishes) and to respond to a questionnaire related to 3 subdomains. In E1, 3 factors were extracted by a factor analysis, and the subsequent multiple regression analyses indicated that the palatability of sake was interpreted by mainly the rewarding. Further, the results of attribution-dissections in E1 indicated that 2 factors (rewarding and informational) contributed to the palatability. Finally, our results indicated that the palatability of sake was influenced by the dish eaten just before drinking.

  4. Relationship between Multiple Intelligence, Reading Proficiency, and Implementing Motivational Strategies: A Study of Iranian Secondary Students

    ERIC Educational Resources Information Center

    Fayazi-Nasab, Ensieh; Ghafournia, Narjes

    2016-01-01

    There exist many factors, affecting reading ability. Multiple intelligence and motivational strategies are among the factors that seem to make significant contribution to the reading process. Thus, the present study probed the probable significant relation between Iranian language learners' multiple intelligences and reading ability. The study…

  5. Structured plant metabolomics for the simultaneous exploration of multiple factors.

    PubMed

    Vasilev, Nikolay; Boccard, Julien; Lang, Gerhard; Grömping, Ulrike; Fischer, Rainer; Goepfert, Simon; Rudaz, Serge; Schillberg, Stefan

    2016-11-17

    Multiple factors act simultaneously on plants to establish complex interaction networks involving nutrients, elicitors and metabolites. Metabolomics offers a better understanding of complex biological systems, but evaluating the simultaneous impact of different parameters on metabolic pathways that have many components is a challenging task. We therefore developed a novel approach that combines experimental design, untargeted metabolic profiling based on multiple chromatography systems and ionization modes, and multiblock data analysis, facilitating the systematic analysis of metabolic changes in plants caused by different factors acting at the same time. Using this method, target geraniol compounds produced in transgenic tobacco cell cultures were grouped into clusters based on their response to different factors. We hypothesized that our novel approach may provide more robust data for process optimization in plant cell cultures producing any target secondary metabolite, based on the simultaneous exploration of multiple factors rather than varying one factor each time. The suitability of our approach was verified by confirming several previously reported examples of elicitor-metabolite crosstalk. However, unravelling all factor-metabolite networks remains challenging because it requires the identification of all biochemically significant metabolites in the metabolomics dataset.

  6. Investigation of the Performance of D 2O-Cooled High-Conversion Reactors for Fuel Cycle Calculations

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

    Hiruta, Hikaru; Youinou, Gilles

    2013-09-01

    This report presents FY13 activities for the analysis of D 2O cooled tight-pitch High-Conversion PWRs (HCPWRs) with U-Pu and Th-U fueled cores aiming at break-even or near breeder conditions while retaining the negative void reactivity. The analyses are carried out from several aspects which could not be covered in FY12 activities. SCALE 6.1 code system is utilized, and a series of simple 3D fuel pin-cell models are developed in order to perform Monte Carlo based criticality and burnup calculations. The performance of U-Pu fueled cores with axial and internal blankets is analyzed in terms of their impact on the relativemore » fissile Pu mass balance, initial Pu enrichment, and void coefficient. In FY12, Pu conversion performances of D 2O-cooled HCPWRs fueled with MOX were evaluated with small sized axial/internal DU blankets (approximately 4cm of axial length) in order to ensure the negative void reactivity, which evidently limits the conversion performance of HCPWRs. In this fiscal year report, the axial sizes of DU blankets are extended up to 30 cm in order to evaluate the amount of DU necessary to reach break-even and/or breeding conditions. Several attempts are made in order to attain the milestone of the HCPWR designs (i.e., break-even condition and negative void reactivity) by modeling of HCPWRs under different conditions such as boiling of D 2O coolant, MOX with different 235U enrichment, and different target burnups. A similar set of analyses are performed for Th-U fueled cores. Several promising characteristics of 233U over other fissile like 239Pu and 235U, most notably its higher fission neutrons per absorption in thermal and epithermal ranges combined with lower ___ in the fast range than 239Pu allows Th-U cores to be taller than MOX ones. Such an advantage results in 4% higher relative fissile mass balance than that of U-Pu fueled cores while retaining the negative void reactivity until the target burnup of 51 GWd/t. Several other distinctions between U-Pu and Th-U fueled cores are identified by evaluating the sensitivity coefficients of keff, mass balance, and void coefficient. The effect of advanced iron alloy cladding (i.e., FeCrAl) on the performance of Pu conversion in MOX fueled cores is studied instead of using standard stainless-steel cladding. Variations in clad thickness and coolant-to-fuel volume ratio are also exercised. The use of FeCrAl instead of SS as a cladding alloy reduces the required Pu enrichment and improves the Pu conversion rate primarily due to the absence of nickel in the cladding alloy that results in the reduction of the neutron absorption. Also the difference in void coefficients between SS and FeCrAl alloys is nearly 500 pcm over the entire burnup range. The report also shows sensitivity and uncertainty analyses in order to characterize D 2O cooled HCPWRs from different aspects. The uncertainties of integral parameters (keff and void coefficient) for selected reactor cores are evaluated at different burnup points in order to find similarities and trends respect to D 2O-HCPWR.« less

  7. Science Teaching Efficacy of Preservice Elementary Teachers: Examination of the Multiple Factors Reported as Influential

    ERIC Educational Resources Information Center

    Tastan Kirik, Özgecan

    2013-01-01

    This study explores the science teaching efficacy beliefs of preservice elementary teachers and the relationship between efficacy beliefs and multiple factors such as antecedent factors (participation in extracurricular activities and number of science and science teaching methods courses taken), conceptual understanding, classroom management…

  8. Interleukin 35 and Hepatocyte Growth Factor; as a novel combined immune gene therapy for Multiple Sclerosis disease.

    PubMed

    Moghadam, Samira; Erfanmanesh, Maryam; Esmaeilzadeh, Abdolreza

    2017-11-01

    An autoimmune demyelination disease of the Central Nervous System, Multiple Sclerosis, is a chronic inflammation which mostly involves young adults. Suffering people face functional loss with a severe pain. Most current MS treatments are focused on the immune response suppression. Approved drugs suppress the inflammatory process, but factually, there is no definite cure for Multiple Sclerosis. Recently developed knowledge has demonstrated that gene and cell therapy as a hopeful approach in tissue regeneration. The authors propose a novel combined immune gene therapy for Multiple Sclerosis treatment using anti-inflammatory and remyelination of Interleukine-35 and Hepatocyte Growth Factor properties, respectively. In this hypothesis Interleukine-35 and Hepatocyte Growth Factor introduce to Mesenchymal Stem Cells of EAE mouse model via an adenovirus based vector. It is expected that Interleukine-35 and Hepatocyte Growth Factor genes expressed from MSCs could effectively perform in immunotherapy of Multiple Sclerosis. Copyright © 2017. Published by Elsevier Ltd.

  9. Medicolegal issues in multiple pregnancy.

    PubMed

    Gersell, Deborah J

    2007-02-01

    Any discussion of multiple pregnancy figures prominently in the consideration of the medicolegal aspects of placental pathology. Multiple gestations are common and becoming more so with assisted reproductive techniques, and multiples are associated with a disproportionate share of complications that may result in disputes over quality of care. Higher rates of intrauterine growth retardation, prematurity, stillbirth, morbidity, mortality, cerebral palsy, anomalous development, and malformation as compared with singletons are well documented in multiple pregnancy and should be anticipated. Monochorionic placentation and complications of vascular anastomosis are important factors contributing to poor outcome. Other factors, although occurring in all gestations, are relevant because they are more common in multiple gestations.

  10. Single and Multiple Suicide Attempts and Associated Health Risk Factors in New Hampshire Adolescents

    ERIC Educational Resources Information Center

    Rosenberg, Harriet J.; Jankowski, Mary K.; Sengupta, Anjana; Wolfe, Rosemarie S.; Wolford, George L., II; Rosenberg, Stanley D.

    2005-01-01

    In this study we examined self-reported suicide attempts and their relationship to other health risk factors in a community sample of 16,644 adolescents. Fifteen percent endorsed suicide attempts (10% single; 5% multiple attempts). We hypothesized that multiple attempters would show higher prevalence of comorbid health risks than single or…

  11. A retrospective likelihood approach for efficient integration of multiple omics factors in case-control association studies.

    PubMed

    Balliu, Brunilda; Tsonaka, Roula; Boehringer, Stefan; Houwing-Duistermaat, Jeanine

    2015-03-01

    Integrative omics, the joint analysis of outcome and multiple types of omics data, such as genomics, epigenomics, and transcriptomics data, constitute a promising approach for powerful and biologically relevant association studies. These studies often employ a case-control design, and often include nonomics covariates, such as age and gender, that may modify the underlying omics risk factors. An open question is how to best integrate multiple omics and nonomics information to maximize statistical power in case-control studies that ascertain individuals based on the phenotype. Recent work on integrative omics have used prospective approaches, modeling case-control status conditional on omics, and nonomics risk factors. Compared to univariate approaches, jointly analyzing multiple risk factors with a prospective approach increases power in nonascertained cohorts. However, these prospective approaches often lose power in case-control studies. In this article, we propose a novel statistical method for integrating multiple omics and nonomics factors in case-control association studies. Our method is based on a retrospective likelihood function that models the joint distribution of omics and nonomics factors conditional on case-control status. The new method provides accurate control of Type I error rate and has increased efficiency over prospective approaches in both simulated and real data. © 2015 Wiley Periodicals, Inc.

  12. Mexican American Adolescents' Profiles of Risk and Mental Health: A Person-Centered Longitudinal Approach

    ERIC Educational Resources Information Center

    Zeiders, Katharine H.; Roosa, Mark W.; Knight, George P.; Gonzales, Nancy A.

    2013-01-01

    Although Mexican American adolescents experience multiple risk factors in their daily lives, most research examines the influences of risk factors on adjustment independently, ignoring the additive and interactive effects of multiple risk factors. Guided by a person-centered perspective and utilizing latent profile analysis, this study identified…

  13. Testing Measurement Invariance Using MIMIC: Likelihood Ratio Test with a Critical Value Adjustment

    ERIC Educational Resources Information Center

    Kim, Eun Sook; Yoon, Myeongsun; Lee, Taehun

    2012-01-01

    Multiple-indicators multiple-causes (MIMIC) modeling is often used to test a latent group mean difference while assuming the equivalence of factor loadings and intercepts over groups. However, this study demonstrated that MIMIC was insensitive to the presence of factor loading noninvariance, which implies that factor loading invariance should be…

  14. Gender Differences in Risk/Protection Profiles for Low Academic Performance

    ERIC Educational Resources Information Center

    Whitney, Stephen D.; Renner, Lynette M.; Herrenkohl, Todd I.

    2010-01-01

    Using holistic-interactionistic theory, the simultaneous nature of risk and protection factors for both males and females (age 6-11 in Wave 1) is examined using latent profile analysis (LPA). Risk/protection classes are estimated using multiple risk factor variables (e.g., physical child abuse) and multiple protective factors (e.g.,…

  15. Quality of life among people with multiple sclerosis: Replication of a three-factor prediction model.

    PubMed

    Bishop, Malachy; Rumrill, Phillip D; Roessler, Richard T

    2015-01-01

    This article presents a replication of Rumrill, Roessler, and Fitzgerald's 2004 analysis of a three-factor model of the impact of multiple sclerosis (MS) on quality of life (QOL). The three factors in the original model included illness-related, employment-related, and psychosocial adjustment factors. To test hypothesized relationships between QOL and illness-related, employment-related, and psychosocial variables using data from a survey of the employment concerns of Americans with MS (N = 1,839). An ex post facto, multiple correlational design was employed incorporating correlational and multiple regression analyses. QOL was positively related to educational level, employment status, job satisfaction, and job-match, and negatively related to number of symptoms, severity of symptoms, and perceived stress level. The three-factor model explained approximately 37 percent of the variance in QOL scores. The results of this replication confirm the continuing value of the three-factor model for predicting the QOL of adults with MS, and demonstrate the importance of medical, mental health, and vocational rehabilitation interventions and services in promoting QOL.

  16. Effect of Multiple Scattering on the Compton Recoil Current Generated in an EMP, Revisited

    DOE PAGES

    Farmer, William A.; Friedman, Alex

    2015-06-18

    Multiple scattering has historically been treated in EMP modeling through the obliquity factor. The validity of this approach is examined here. A simplified model problem, which correctly captures cyclotron motion, Doppler shifting due to the electron motion, and multiple scattering is first considered. The simplified problem is solved three ways: the obliquity factor, Monte-Carlo, and Fokker-Planck finite-difference. Because of the Doppler effect, skewness occurs in the distribution. It is demonstrated that the obliquity factor does not correctly capture this skewness, but the Monte-Carlo and Fokker-Planck finite-difference approaches do. Here, the obliquity factor and Fokker-Planck finite-difference approaches are then compared inmore » a fuller treatment, which includes the initial Klein-Nishina distribution of the electrons, and the momentum dependence of both drag and scattering. It is found that, in general, the obliquity factor is adequate for most situations. However, as the gamma energy increases and the Klein-Nishina becomes more peaked in the forward direction, skewness in the distribution causes greater disagreement between the obliquity factor and a more accurate model of multiple scattering.« less

  17. Multiple pregnancy, short cervix, part-time worker, steroid use, low educational level and male fetus are risk factors for preterm birth in Japan: a multicenter, prospective study.

    PubMed

    Shiozaki, Arihiro; Yoneda, Satoshi; Nakabayashi, Masao; Takeda, Yoshiharu; Takeda, Satoru; Sugimura, Motoi; Yoshida, Koyo; Tajima, Atsushi; Manabe, Mami; Akagi, Kozo; Nakagawa, Shoko; Tada, Katsuhiko; Imafuku, Noriaki; Ogawa, Masanobu; Mizunoe, Tomoya; Kanayama, Naohiro; Itoh, Hiroaki; Minoura, Shigeki; Ogino, Mitsuharu; Saito, Shigeru

    2014-01-01

    To examine the relationship between preterm birth and socioeconomic factors, past history, cervical length, cervical interleukin-8, bacterial vaginosis, underlying diseases, use of medication, employment status, sex of the fetus and multiple pregnancy. In a multicenter, prospective, observational study, 1810 Japanese women registering their future delivery were enrolled at 8⁺⁰ to 12⁺⁶ weeks of gestation. Data on cervical length and delivery were obtained from 1365 pregnant women. Multivariate logistic regression analysis was performed. Short cervical length, steroid use, multiple pregnancy and male fetus were risk factors for preterm birth before 34 weeks of gestation. Multiple pregnancy, low educational level, short cervical length and part-timer were risk factors for preterm birth before 37 weeks of gestation. Multiple pregnancy and cervical shortening at 20-24 weeks of gestation was a stronger risk factor for preterm birth. Any pregnant woman being part-time employee or low educational level, having a male fetus and requiring steroid treatment should be watched for the development of preterm birth. © 2013 The Authors. Journal of Obstetrics and Gynaecology Research © 2013 Japan Society of Obstetrics and Gynecology.

  18. Pediatric Multiple Sclerosis: Genes, Environment, and a Comprehensive Therapeutic Approach.

    PubMed

    Cappa, Ryan; Theroux, Liana; Brenton, J Nicholas

    2017-10-01

    Pediatric multiple sclerosis is an increasingly recognized and studied disorder that accounts for 3% to 10% of all patients with multiple sclerosis. The risk for pediatric multiple sclerosis is thought to reflect a complex interplay between environmental and genetic risk factors. Environmental exposures, including sunlight (ultraviolet radiation, vitamin D levels), infections (Epstein-Barr virus), passive smoking, and obesity, have been identified as potential risk factors in youth. Genetic predisposition contributes to the risk of multiple sclerosis, and the major histocompatibility complex on chromosome 6 makes the single largest contribution to susceptibility to multiple sclerosis. With the use of large-scale genome-wide association studies, other non-major histocompatibility complex alleles have been identified as independent risk factors for the disease. The bridge between environment and genes likely lies in the study of epigenetic processes, which are environmentally-influenced mechanisms through which gene expression may be modified. This article will review these topics to provide a framework for discussion of a comprehensive approach to counseling and ultimately treating the pediatric patient with multiple sclerosis. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Testing Group Mean Differences of Latent Variables in Multilevel Data Using Multiple-Group Multilevel CFA and Multilevel MIMIC Modeling.

    PubMed

    Kim, Eun Sook; Cao, Chunhua

    2015-01-01

    Considering that group comparisons are common in social science, we examined two latent group mean testing methods when groups of interest were either at the between or within level of multilevel data: multiple-group multilevel confirmatory factor analysis (MG ML CFA) and multilevel multiple-indicators multiple-causes modeling (ML MIMIC). The performance of these methods were investigated through three Monte Carlo studies. In Studies 1 and 2, either factor variances or residual variances were manipulated to be heterogeneous between groups. In Study 3, which focused on within-level multiple-group analysis, six different model specifications were considered depending on how to model the intra-class group correlation (i.e., correlation between random effect factors for groups within cluster). The results of simulations generally supported the adequacy of MG ML CFA and ML MIMIC for multiple-group analysis with multilevel data. The two methods did not show any notable difference in the latent group mean testing across three studies. Finally, a demonstration with real data and guidelines in selecting an appropriate approach to multilevel multiple-group analysis are provided.

  20. Multiple sex partner behavior in female undergraduate students in China: a multi-campus survey.

    PubMed

    Yan, Hong; Chen, Weiqi; Wu, Haocheng; Bi, Yongyi; Zhang, Miaoxuan; Li, Shiyue; Braun, Kathryn L

    2009-08-22

    China is realizing increases in women engaged in premarital sex and multiple sex partner behavior. Our aim was to examine prevalence and determinants of multiple sex partner behavior among female undergraduates in China. Anonymously completed questionnaires were received from 4,769 unmarried female undergraduates, recruited using randomized cluster sampling by type of university and students' major and grade. Items captured demographic, family, peer and work influence, and student factors (major, academic performance, and sex-related knowledge and attitudes). To examine risk factors for sexual behaviors, we used multi-level logistic regression, yielding odds ratios (OR) and 95% confidence intervals (95% CI). Of 4,769 female students, 863 (18.10%) reported ever having sexual intercourse, and 5.31% reported having multiple sex partners (29.32% of all women having sexual intercourse). Several demographic, family, peer and work influences, and student factors (including major, performance, knowledge, and attitude toward sex) were risk factors for ever having sex. However, risk factors for multiple sex partners only included working in a place of entertainment, having current close friends that were living with boyfriends, poor academic performance, and positive attitudes toward multiple partners. These women also were more likely to practice masturbation, start having sex at a younger age, have sex with married men and/or men not their "boyfriends" at first coitus, and not use condoms consistently. A small but important subset of Chinese female undergraduates is engaged in unprotected sex with multiple sex partners. Interventions need to target at risk women, stressing the importance of consistent condom use.

  1. Multiple sex partner behavior in female undergraduate students in China: A multi-campus survey

    PubMed Central

    Yan, Hong; Chen, Weiqi; Wu, Haocheng; Bi, Yongyi; Zhang, Miaoxuan; Li, Shiyue; Braun, Kathryn L

    2009-01-01

    Background China is realizing increases in women engaged in premarital sex and multiple sex partner behavior. Our aim was to examine prevalence and determinants of multiple sex partner behavior among female undergraduates in China. Methods Anonymously completed questionnaires were received from 4,769 unmarried female undergraduates, recruited using randomized cluster sampling by type of university and students' major and grade. Items captured demographic, family, peer and work influence, and student factors (major, academic performance, and sex-related knowledge and attitudes). To examine risk factors for sexual behaviors, we used multi-level logistic regression, yielding odds ratios (OR) and 95% confidence intervals (95% CI). Results Of 4,769 female students, 863 (18.10%) reported ever having sexual intercourse, and 5.31% reported having multiple sex partners (29.32% of all women having sexual intercourse). Several demographic, family, peer and work influences, and student factors (including major, performance, knowledge, and attitude toward sex) were risk factors for ever having sex. However, risk factors for multiple sex partners only included working in a place of entertainment, having current close friends that were living with boyfriends, poor academic performance, and positive attitudes toward multiple partners. These women also were more likely to practice masturbation, start having sex at a younger age, have sex with married men and/or men not their "boyfriends" at first coitus, and not use condoms consistently. Conclusion A small but important subset of Chinese female undergraduates is engaged in unprotected sex with multiple sex partners. Interventions need to target at risk women, stressing the importance of consistent condom use. PMID:19698132

  2. Gestational bisphenol-A exposure lowers the threshold for autoimmunity in a model of multiple sclerosis.

    PubMed

    Rogers, James A; Mishra, Manoj K; Hahn, Jennifer; Greene, Catherine J; Yates, Robin M; Metz, Luanne M; Yong, V Wee

    2017-05-09

    Environmental and hormonal factors are implicated in dysimmunity in multiple sclerosis. We investigated whether bisphenol-A, a prominent contaminant with endocrine-disrupting capabilities, altered susceptibility in an inflammatory model of multiple sclerosis. We found that gestational, but not adult, exposure to bisphenol-A increased the development of experimental autoimmune encephalomyelitis in adulthood in male, but not female, mice when a suboptimal disease-inducing immunization was used. Gestational bisphenol-A in male mice primed macrophages in adulthood and raised granulocyte-colony stimulating factor and neutrophil counts/activity postsuboptimal immunization. Neutralizing granulocyte-colony stimulating factor blocked susceptibility to disease in bisphenol-A mice. Early life exposure to bisphenol-A may represent an environmental consideration in multiple sclerosis.

  3. Impact of high-intensity concurrent training on cardiovascular risk factors in persons with multiple sclerosis - pilot study.

    PubMed

    Keytsman, Charly; Hansen, Dominique; Wens, Inez; O Eijnde, Bert

    2017-10-27

    High-intensity concurrent training positively affects cardiovascular risk factors. Because this was never investigated in multiple sclerosis, the present pilot study explored the impact of this training on cardiovascular risk factors in this population. Before and after 12 weeks of high-intense concurrent training (interval and strength training, 5 sessions per 2 weeks, n = 16) body composition, resting blood pressure and heart rate, 2-h oral glucose tolerance (insulin sensitivity, glycosylated hemoglobin, blood glucose and insulin concentrations), blood lipids (high- and low-density lipoprotein, total cholesterol, triglyceride levels) and C-reactive protein were analyzed. Twelve weeks of high-intense concurrent training significantly improved resting heart rate (-6%), 2-h blood glucose concentrations (-13%) and insulin sensitivity (-24%). Blood pressure, body composition, blood lipids and C-reactive protein did not seem to be affected. Under the conditions of this pilot study, 12 weeks of concurrent high-intense interval and strength training improved resting heart rate, 2-h glucose and insulin sensitivity in multiple sclerosis but did not affect blood C-reactive protein levels, blood pressure, body composition and blood lipid profiles. Further, larger and controlled research investigating the effects of high-intense concurrent training on cardiovascular risk factors in multiple sclerosis is warranted. Implications for rehabilitation High-intensity concurrent training improves cardiovascular fitness. This pilot study explores the impact of this training on cardiovascular risk factors in multiple sclerosis. Despite the lack of a control group, high-intense concurrent training does not seem to improve cardiovascular risk factors in multiple sclerosis.

  4. Overall Preference of Running Shoes Can Be Predicted by Suitable Perception Factors Using a Multiple Regression Model.

    PubMed

    Tay, Cheryl Sihui; Sterzing, Thorsten; Lim, Chen Yen; Ding, Rui; Kong, Pui Wah

    2017-05-01

    This study examined (a) the strength of four individual footwear perception factors to influence the overall preference of running shoes and (b) whether these perception factors satisfied the nonmulticollinear assumption in a regression model. Running footwear must fulfill multiple functional criteria to satisfy its potential users. Footwear perception factors, such as fit and cushioning, are commonly used to guide shoe design and development, but it is unclear whether running-footwear users are able to differentiate one factor from another. One hundred casual runners assessed four running shoes on a 15-cm visual analogue scale for four footwear perception factors (fit, cushioning, arch support, and stability) as well as for overall preference during a treadmill running protocol. Diagnostic tests showed an absence of multicollinearity between factors, where values for tolerance ranged from .36 to .72, corresponding to variance inflation factors of 2.8 to 1.4. The multiple regression model of these four footwear perception variables accounted for 77.7% to 81.6% of variance in overall preference, with each factor explaining a unique part of the total variance. Casual runners were able to rate each footwear perception factor separately, thus assigning each factor a true potential to improve overall preference for the users. The results also support the use of a multiple regression model of footwear perception factors to predict overall running shoe preference. Regression modeling is a useful tool for running-shoe manufacturers to more precisely evaluate how individual factors contribute to the subjective assessment of running footwear.

  5. Multiple factor indices of protection or risk towards disease.

    PubMed

    Belfiore, F; Iannello, S

    2001-02-01

    In order to combine several factors entailing protection or risk towards disease and to calculate a Protection Multiple Factor Index (PMFI) or, conversely, a Risk Multiple Factor Index (RMFI), we propose the following formulae: (1) PMFI = 2/[(mF)2 + 1] and (2) RMFI = 2/[(imF)2 + 1], where mF is the mean value of the factors considered and imF is the inverse (or reciprocal) of mF. In calculating mF, the value of each 'risk factor' observed in the patient under study (Vp) is expressed by taking the mean normal value (Vmn) as the unit, i.e. by calculating the ratio Vp/Vmn, whereas each 'protection factor' is expressed as the reciprocal of this ratio, i.e. as Vmn/Vp. The 'weight' of the various factors can be changed through multiplication by a number > 1 or < 1. Values of both PMFI and RMFI are always close to 1 in normal subjects, with extreme variations among patients between 0 and 2. The sum of the values of PMFI and RMFI is always equal to 2, so that one index can be deduced from the other. When factors are only two (F1 and F2), the formulae may be simplified as follows: PMFI = 2/[F1 x F2) + 1] and RMFI = 2/[(iF1 x iF2) + 1], where iF = 1/F, with only minimal changes in results.

  6. Classification and Clustering Methods for Multiple Environmental Factors in Gene-Environment Interaction: Application to the Multi-Ethnic Study of Atherosclerosis.

    PubMed

    Ko, Yi-An; Mukherjee, Bhramar; Smith, Jennifer A; Kardia, Sharon L R; Allison, Matthew; Diez Roux, Ana V

    2016-11-01

    There has been an increased interest in identifying gene-environment interaction (G × E) in the context of multiple environmental exposures. Most G × E studies analyze one exposure at a time, but we are exposed to multiple exposures in reality. Efficient analysis strategies for complex G × E with multiple environmental factors in a single model are still lacking. Using the data from the Multiethnic Study of Atherosclerosis, we illustrate a two-step approach for modeling G × E with multiple environmental factors. First, we utilize common clustering and classification strategies (e.g., k-means, latent class analysis, classification and regression trees, Bayesian clustering using Dirichlet Process) to define subgroups corresponding to distinct environmental exposure profiles. Second, we illustrate the use of an additive main effects and multiplicative interaction model, instead of the conventional saturated interaction model using product terms of factors, to study G × E with the data-driven exposure subgroups defined in the first step. We demonstrate useful analytical approaches to translate multiple environmental exposures into one summary class. These tools not only allow researchers to consider several environmental exposures in G × E analysis but also provide some insight into how genes modify the effect of a comprehensive exposure profile instead of examining effect modification for each exposure in isolation.

  7. Research on the Multiple Factors Influencing Human Identification Based on Pyroelectric Infrared Sensors

    PubMed Central

    Lou, Ping; Hu, Jianmin

    2018-01-01

    Analysis of the multiple factors affecting human identification ability based on pyroelectric infrared technology is a complex problem. First, we examine various sensed pyroelectric waveforms of the human body thermal infrared signal and reveal a mechanism for affecting human identification. Then, we find that the mechanism is decided by the distance, human target, pyroelectric infrared (PIR) sensor, the body type, human moving velocity, signal modulation mask, and Fresnel lens. The mapping relationship between the sensed waveform and multiple influencing factors is established, and a group of mathematical models are deduced which fuse the macro factors and micro factors. Finally, the experimental results show the macro-factors indirectly affect the recognition ability of human based on the pyroelectric technology. At the same time, the correctness and effectiveness of the mathematical models is also verified, which make it easier to obtain more pyroelectric infrared information about the human body for discriminating human targets. PMID:29462908

  8. [Future challenges in multiple sclerosis].

    PubMed

    Fernández, Óscar

    2014-12-01

    Multiple sclerosis occurs in genetically susceptible individuals, in whom an unknown environmental factor triggers an immune response, giving rise to a chronic and disabling autoimmune disease. Currently, significant progress is being made in our knowledge of the frequency and distribution of multiple sclerosis and its risk factors, genetics, pathology, pathogenesis, diagnostic and prognostic markers, and treatment. This has radically changed patients' and clinicians' expectations of multiple sclerosis and has raised hope that there will soon be a way to control the disease. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  9. Factors Influencing Amount of Weekly Exercise Time in Colorectal Cancer Survivors.

    PubMed

    Chou, Yun-Jen; Lai, Yeur-Hur; Lin, Been-Ren; Liang, Jin-Tung; Shun, Shiow-Ching

    Performing regular exercise of at least 150 minutes weekly has benefits for colorectal cancer survivors. However, barriers inhibit these survivors from performing regular exercise. The aim of this study was to explore exercise behaviors and significant factors influencing weekly exercise time of more than 150 minutes in colorectal cancer survivors. A cross-sectional study design was used to recruit participants in Taiwan. Guided by the ecological model of health behavior, exercise barriers were assessed including intrapersonal, interpersonal, and environment-related barriers. A multiple logistic regression was used to explore the factors associated with the amount of weekly exercise. Among 321 survivors, 57.0% of them had weekly exercise times of more than 150 minutes. The results identified multiple levels of significant factors related to weekly exercise times including intrapersonal factors (occupational status, functional status, pain, interest in exercise, and beliefs about the importance of exercise) and exercise barriers related to environmental factors (lack of time and bad weather). No interpersonal factors were found to be significant. Colorectal cancer survivors experienced low levels of physical and psychological distress. Multiple levels of significant factors related to exercise time including intrapersonal factors as well as exercise barriers related to environmental factors should be considered. Healthcare providers should discuss with their patients how to perform exercise programs; the discussion should address multiple levels of the ecological model such as any pain problems, functional status, employment status, and time limitations, as well as community environment.

  10. Managing Multiple Tasks in Complex, Dynamic Environments

    NASA Technical Reports Server (NTRS)

    Freed, Michael; Null, Cynthia H. (Technical Monitor)

    1998-01-01

    Sketchy planners are designed to achieve goals in realistically complex, time-pressured, and uncertain task environments. However, the ability to manage multiple, potentially interacting tasks in such environments requires extensions to the functionality these systems typically provide. This paper identifies a number of factors affecting how interacting tasks should be prioritized, interrupted, and resumed, and then describes a sketchy planner called APEX that takes account of these factors when managing multiple tasks.

  11. Importance of dual delivery systems for bone tissue engineering.

    PubMed

    Farokhi, Mehdi; Mottaghitalab, Fatemeh; Shokrgozar, Mohammad Ali; Ou, Keng-Liang; Mao, Chuanbin; Hosseinkhani, Hossein

    2016-03-10

    Bone formation is a complex process that requires concerted function of multiple growth factors. For this, it is essential to design a delivery system with the ability to load multiple growth factors in order to mimic the natural microenvironment for bone tissue formation. However, the short half-lives of growth factors, their relatively large size, slow tissue penetration, and high toxicity suggest that conventional routes of administration are unlikely to be effective. Therefore, it seems that using multiple bioactive factors in different delivery systems can develop new strategies for improving bone tissue regeneration. Combination of these factors along with biomaterials that permit tunable release profiles would help to achieve truly spatiotemporal regulation during delivery. This review summarizes the various dual-control release systems that are used for bone tissue engineering. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Examining the factor structure of the Multiple Sclerosis Impact Scale.

    PubMed

    Fitzgerald, Shawn M; Li, Jian; Rumrill, Phillip D; Merchant, William; Bishop, Malachy

    2014-01-01

    The purpose of this study was to investigate the factor structure of the Multiple Sclerosis Impact Scale (MSIS-29) to assess its suitability for modeling the impact of MS on a nation-wide sample of individuals from the United States. Investigators completed a Confirmatory Factor Analysis (CFA) to examine the two-factor structure proposed by Hobart et al. [17]. Although the original MSIS-29 factor structure did not fit the data exactly, the hypothesized two-factor model was partially supported in the current data. Implications for future instrument development and rehabilitation practice are discussed.

  13. Multiplicative Effects of Social and Psychological Risk Factors on College Students' Suicidal Behaviors.

    PubMed

    Assari, Shervin

    2018-05-17

    Less is known about the multiplicative effects of social and psychological risk and protective factors of suicidality on college campuses. The current study aimed to investigate the multiplicative effects of social (identifying oneself as gay/lesbian, financial difficulty, violence victimization, and religiosity) and psychological (anxiety, depression, problem alcohol use, drug use) and risk/protective factors on suicidal behaviors among college students in the United States. Using a cross-sectional design, the Healthy Mind Study (HMS; 2016⁻2017), is a national online survey of college students in the United States. Social (identifying oneself as gay/lesbian, violence victimization, financial difficulty, and religiosity) and psychological (anxiety, depression, problem alcohol use, and drug use) risk/protective factors were assessed among 27,961 individuals. Three aspects of suicidality, including ideation, plan, and attempt, were also assessed. Logistic regression models were used for data analysis. Financial difficulty, violence victimization, identifying oneself as gay/lesbian, anxiety, depression, and drug use increased, while religiosity reduced the odds of suicidal behaviors. Multiplicative effects were found between the following social and psychological risk factors: (1) financial difficulty and anxiety; (2) financial difficulty and depression; (3) depression and drug use; (4) problem alcohol use and drug use; and (5) depression and problem alcohol use. There is a considerable overlap in the social and psychological processes, such as financial stress, mood disorders, and substance use problems, on risk of suicide in college students. As social and psychological risk factors do not operate independently, comprehensive suicidal risk evaluations that simultaneously address multiple social and psychological risk factors may be superior to programs that only address a single risk factor.

  14. Measuring the effects of socioeconomic factors on mental health among migrants in urban China: a multiple indicators multiple causes model.

    PubMed

    Guan, Ming

    2017-01-01

    Since 1978, rural-urban migrants mainly contribute Chinese urbanization. The purpose of this paper is to examine the effects of socioeconomic factors on mental health of them. Their mental health was measured by 12-item general health questionnaire (GHQ-12). The study sample comprised 5925 migrants obtained from the 2009 rural-to-urban migrants survey (RUMiC). The relationships among the instruments were assessed by the correlation analysis. The one-factor (overall items), two-factor (positive vs. negative items), and model conducted by principal component analysis were tested in the confirmatory factor analysis (CFA). On the basis of three CFA models, the three multiple indicators multiple causes (MIMIC) models with age, gender, marriage, ethnicity, and employment were constructed to investigate the concurrent associations between socioeconomic factors and GHQ-12. Of the sample, only 1.94% were of ethnic origin and mean age was 31.63 (SD = ±10.43) years. The one-factor, two-factor, and three-factor structure (i.e. semi-positive/negative/independent usefulness) had good model fits in the CFA analysis and gave order (i.e. 2 factor>3 factor>1 factor), which suggests that the three models can be used to assess psychological symptoms of migrants in urban China. All MIMIC models had acceptable fit and gave order (i.e. one-dimensional model>two-dimensional model>three-dimensional model). There were weak associations of socioeconomic factors with mental health among migrants in urban China. Policy discussion suggested that improvement of socioeconomic status of rural-urban migrants and mental health systems in urban China should be highlighted and strengthened.

  15. Set of Criteria for Efficiency of the Process Forming the Answers to Multiple-Choice Test Items

    ERIC Educational Resources Information Center

    Rybanov, Alexander Aleksandrovich

    2013-01-01

    Is offered the set of criteria for assessing efficiency of the process forming the answers to multiple-choice test items. To increase accuracy of computer-assisted testing results, it is suggested to assess dynamics of the process of forming the final answer using the following factors: loss of time factor and correct choice factor. The model…

  16. Protective factors associated with fewer multiple problem behaviors among homeless/runaway youth.

    PubMed

    Lightfoot, Marguerita; Stein, Judith A; Tevendale, Heather; Preston, Kathleen

    2011-01-01

    Although homeless youth exhibit numerous problem behaviors, protective factors that can be targeted and modified by prevention programs to decrease the likelihood of involvement in risky behaviors are less apparent. The current study tested a model of protective factors for multiple problem behavior in a sample of 474 homeless youth (42% girls; 83% minority) ages 12 to 24 years. Higher levels of problem solving and planning skills were strongly related to lower levels of multiple problem behaviors in homeless youth, suggesting both the positive impact of preexisting personal assets of these youth and important programmatic targets for further building their resilience and decreasing problem behaviors. Indirect relationships between the background factors of self-esteem and social support and multiple problem behaviors were significantly mediated through protective skills. The model suggests that helping youth enhance their skills in goal setting, decision making, and self-reliant coping could lessen a variety of problem behaviors commonly found among homeless youth.

  17. Protective Factors Associated with Fewer Multiple Problem Behaviors Among Homeless/Runaway Youth

    PubMed Central

    Lightfoot, Marguerita; Stein, Judith A.; Tevendale, Heather; Preston, Kathleen

    2015-01-01

    Although homeless youth exhibit numerous problem behaviors, protective factors that can be targeted and modified by prevention programs to decrease the likelihood of involvement in risky behaviors are less apparent. The current study tested a model of protective factors for multiple problem behavior in a sample of 474 homeless youth (42% girls; 83% minority) ages 12 to 24 years. Higher levels of problem solving and planning skills were strongly related to lower levels of multiple problem behaviors in homeless youth, suggesting both the positive impact of preexisting personal assets of these youth and important programmatic targets for further building their resilience and decreasing problem behaviors. Indirect relationships between the background factors of self-esteem and social support and multiple problem behaviors were significantly mediated through protective skills. The model suggests that helping youth enhance their skills in goal setting, decision making, and self-reliant coping could lessen a variety of problem behaviors commonly found among homeless youth. PMID:22023279

  18. Analysis and prediction of Multiple-Site Damage (MSD) fatigue crack growth

    NASA Technical Reports Server (NTRS)

    Dawicke, D. S.; Newman, J. C., Jr.

    1992-01-01

    A technique was developed to calculate the stress intensity factor for multiple interacting cracks. The analysis was verified through comparison with accepted methods of calculating stress intensity factors. The technique was incorporated into a fatigue crack growth prediction model and used to predict the fatigue crack growth life for multiple-site damage (MSD). The analysis was verified through comparison with experiments conducted on uniaxially loaded flat panels with multiple cracks. Configuration with nearly equal and unequal crack distribution were examined. The fatigue crack growth predictions agreed within 20 percent of the experimental lives for all crack configurations considered.

  19. Evidence from intrinsic activity that asymmetry of the human brain is controlled by multiple factors.

    PubMed

    Liu, Hesheng; Stufflebeam, Steven M; Sepulcre, Jorge; Hedden, Trey; Buckner, Randy L

    2009-12-01

    Cerebral lateralization is a fundamental property of the human brain and a marker of successful development. Here we provide evidence that multiple mechanisms control asymmetry for distinct brain systems. Using intrinsic activity to measure asymmetry in 300 adults, we mapped the most strongly lateralized brain regions. Both men and women showed strong asymmetries with a significant, but small, group difference. Factor analysis on the asymmetric regions revealed 4 separate factors that each accounted for significant variation across subjects. The factors were associated with brain systems involved in vision, internal thought (the default network), attention, and language. An independent sample of right- and left-handed individuals showed that hand dominance affects brain asymmetry but differentially across the 4 factors supporting their independence. These findings show the feasibility of measuring brain asymmetry using intrinsic activity fluctuations and suggest that multiple genetic or environmental mechanisms control cerebral lateralization.

  20. Adaptive and bounded investment returns promote cooperation in spatial public goods games.

    PubMed

    Chen, Xiaojie; Liu, Yongkui; Zhou, Yonghui; Wang, Long; Perc, Matjaž

    2012-01-01

    The public goods game is one of the most famous models for studying the evolution of cooperation in sizable groups. The multiplication factor in this game can characterize the investment return from the public good, which may be variable depending on the interactive environment in realistic situations. Instead of using the same universal value, here we consider that the multiplication factor in each group is updated based on the differences between the local and global interactive environments in the spatial public goods game, but meanwhile limited to within a certain range. We find that the adaptive and bounded investment returns can significantly promote cooperation. In particular, full cooperation can be achieved for high feedback strength when appropriate limitation is set for the investment return. Also, we show that the fraction of cooperators in the whole population can become larger if the lower and upper limits of the multiplication factor are increased. Furthermore, in comparison to the traditionally spatial public goods game where the multiplication factor in each group is identical and fixed, we find that cooperation can be better promoted if the multiplication factor is constrained to adjust between one and the group size in our model. Our results highlight the importance of the locally adaptive and bounded investment returns for the emergence and dominance of cooperative behavior in structured populations.

  1. Adaptive and Bounded Investment Returns Promote Cooperation in Spatial Public Goods Games

    PubMed Central

    Chen, Xiaojie; Liu, Yongkui; Zhou, Yonghui; Wang, Long; Perc, Matjaž

    2012-01-01

    The public goods game is one of the most famous models for studying the evolution of cooperation in sizable groups. The multiplication factor in this game can characterize the investment return from the public good, which may be variable depending on the interactive environment in realistic situations. Instead of using the same universal value, here we consider that the multiplication factor in each group is updated based on the differences between the local and global interactive environments in the spatial public goods game, but meanwhile limited to within a certain range. We find that the adaptive and bounded investment returns can significantly promote cooperation. In particular, full cooperation can be achieved for high feedback strength when appropriate limitation is set for the investment return. Also, we show that the fraction of cooperators in the whole population can become larger if the lower and upper limits of the multiplication factor are increased. Furthermore, in comparison to the traditionally spatial public goods game where the multiplication factor in each group is identical and fixed, we find that cooperation can be better promoted if the multiplication factor is constrained to adjust between one and the group size in our model. Our results highlight the importance of the locally adaptive and bounded investment returns for the emergence and dominance of cooperative behavior in structured populations. PMID:22615836

  2. HIF-2α-ILK Is Involved in Mesenchymal Stromal Cell Angiogenesis in Multiple Myeloma Under Hypoxic Conditions

    PubMed Central

    Zhang, Xiaoying; Xu, Yinhui; Liu, Hongbo; Zhao, Pan; Chen, Yafang; Yue, Zhijie; Zhang, Zhiqing; Wang, Xiaofang

    2018-01-01

    Mesenchymal stromal cells are proven to be likely induce the angiogenic response in multiple myeloma and thus represent an enticing target for antiangiogenesis therapies for multiple myeloma. Substantial evidence indicates that angiogenesis in multiple myeloma is complex and involves direct production of angiogenic cytokines by abnormal plasma cells and these B-cell neoplasia generated pathophysiology change within the microenvironment. In this study, we demonstrated that mesenchymal stromal cells cultured with U266/Lp-1 under hypoxic conditions resulted in an increased α-smooth muscle actin expression and high productive levels of both hypoxia-inducible factor-2α and integrin-linked kinase proteins. Moreover, inhibition of hypoxia-inducible factor-2α by Small interfering RNA (siRNA) in mesenchymal stromal cells decreased the protein levels of both α-smooth muscle actin and integrin-linked kinase after mesenchymal stromal cells cultured with U266 under hypoxic conditions. We further demonstrated that transfection of integrin-linked kinase-siRNA reduced the protein level of α-smooth muscle actin and attenuated angiogenesis in vitro by decreasing the attachment of Q-dot labeled cells and secretion of angiogenic factors. In conclusion, our research showed that mesenchymal stromal cells cultured with myeloma cells under hypoxia participated in the angiogenesis of multiple myeloma, which is regulated by the hypoxia-inducible factor-2α-integrin-linked kinase pathway. Thus, targeting integrin-linked kinase may represent an effective strategy to block hypoxia-inducible factor-2α-induced angiogenesis in the treatment of multiple myeloma. PMID:29656700

  3. [Assessment of exposure to tobacco smoke in a selected group of patients with multiple sclerosis from the Upper Silesia region].

    PubMed

    Dobosz, Cezary; Tyrpień, Krystyna; Pierzchała, Krystyna

    2012-01-01

    In recent years, the increase in the incidence of multiple sclerosis (MS - Multiple Sclerosis) is observed. and the direct cause of the symptoms of multiple sclerosis is myelin nerves damage. It can be concluded that the environmental factor is at least partly responsible for the occurrence of this disease. For the development of this disease are responsible, in addition to genetic factors, compounds present in many parts of the environment. Many of these compounds may adversely affect the redox equilibrium of the body, exacerbating radicalgenesis and decreasing antioxidant defenses. Multiple sclerosis is usually diagnosed in early adulthood, during most daily activities. Effects of SM on living standards includes not only the medical aspect, but also social, economic and emotional aspect. Polish population is a high risk zone regarding multiple sclerosis. The aim of this study was a preliminary assessment of selected environmental exposure factors in the pathogenesis of multiple sclerosis with regard to exposure to tobacco smoke with the author's survey of patients from the region of Upper Silesia. Most MS patients (32) in the study group (suffering from MS from 2 to 44 years) are inhabitants of agglomeration of over 50 thousand citizens, from the area of Gliwice, Bytom and Zabrze (43.75%). In investigated group 46.88% MS patients from Silesia region were exposed to tobacco smoke, of which 21.88% actively smoke. Patients with MS, in order not to worsen their disease manifestation, should stop smoking and increase, if possible, any physical activities. These data will be incorporated into a wide-ranging research to clarify the role of selected environmental factors in a very complex and still not fully explored the pathogenesis of multiple sclerosis in Upper Silesia.

  4. Treatment Results of Postoperative Radiotherapy on Squamous Cell Carcinoma of the Oral Cavity: Coexistence of Multiple Minor Risk Factors Results in Higher Recurrence Rates

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

    Fan, Kang-Hsing; Taipei Chang Gung Head and Neck Oncology Group, Chang Gung Memorial Hospital, Taiwan; Graduate Institute of Clinical Medical Sciences, Taiwan

    2010-07-15

    Purpose: The aim of this study was to investigate the treatment results of postoperative radiotherapy (PORT) on squamous cell carcinoma of the oral cavity (OSCC). Materials and Methods: This study included 302 OSCC patients who were treated by radical surgery and PORT. Indications for PORT include Stage III or IV OSCC according to the 2002 criteria of the American Joint Committee on Cancer, the presence of perineural invasion or lymphatic invasion, the depth of tumor invasion, or a close surgical margin. Patients with major risk factors, such as multiple nodal metastases, a positive surgical margin, or extracapsular spreading, were excluded.more » The prescribed dose of PORT ranged from 59.4 to 66.6Gy (median, 63Gy). Results: The 3-year overall and recurrence-free survival rates were 73% and 70%, respectively. Univariate analysis revealed that differentiation, perineural invasion, lymphatic invasion, bone invasion, location (hard palate and retromolar trigone), invasion depths {>=}10mm, and margin distances {<=}4mm were significant prognostic factors. The presence of multiple significant factors of univariate analysis correlated with disease recurrence. The 3-year recurrence-free survival rates were 82%, 76%, and 45% for patients with no risk factors, one or two risk factors, and three or more risk factors, respectively. After multivariate analysis, the number of risk factors and lymphatic invasion were significant prognostic factors. Conclusion: PORT may be an adequate adjuvant therapy for OSCC patients with one or two risk factors of recurrence. The presence of multiple risk factors and lymphatic invasion correlated with poor prognosis, and more aggressive treatment may need to be considered.« less

  5. 40 CFR 86.1806-04 - On-board diagnostics.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 2002). (vii) As an alternative to the above standards, heavy-duty vehicles may conform to the... standards shall utilize multiplicative factors from the California vehicle type (i.e. LEV II, ULEV II... standards shall utilize the Tier 2 Bin 4 emission standards and the CARB ULEV II multiplicative factors to...

  6. Use of multiple methods to determine factors affecting quality of care of patients with diabetes.

    PubMed

    Khunti, K

    1999-10-01

    The process of care of patients with diabetes is complex; however, GPs are playing a greater role in its management. Despite the research evidence, the quality of care of patients with diabetes is variable. In order to improve care, information is required on the obstacles faced by practices in improving care. Qualitative and quantitative methods can be used for formation of hypotheses and the development of survey procedures. However, to date few examples exist in general practice research on the use of multiple methods using both quantitative and qualitative techniques for hypothesis generation. We aimed to determine information on all factors that may be associated with delivery of care to patients with diabetes. Factors for consideration on delivery of diabetes care were generated by multiple qualitative methods including brainstorming with health professionals and patients, a focus group and interviews with key informants which included GPs and practice nurses. Audit data showing variations in care of patients with diabetes were used to stimulate the brainstorming session. A systematic literature search focusing on quality of care of patients with diabetes in primary care was also conducted. Fifty-four potential factors were identified by multiple methods. Twenty (37.0%) were practice-related factors, 14 (25.9%) were patient-related factors and 20 (37.0%) were organizational factors. A combination of brainstorming and the literature review identified 51 (94.4%) factors. Patients did not identify factors in addition to those identified by other methods. The complexity of delivery of care to patients with diabetes is reflected in the large number of potential factors identified in this study. This study shows the feasibility of using multiple methods for hypothesis generation. Each evaluation method provided unique data which could not otherwise be easily obtained. This study highlights a way of combining various traditional methods in an attempt to overcome the deficiencies and bias that may occur when using a single method. Similar methods can also be used to generate hypotheses for other exploratory research. An important responsibility of health authorities and primary care groups will be to assess the health needs of their local populations. Multiple methods could also be used to identify and commission services to meet these needs.

  7. The impact of attachment and depression symptoms on multiple risk behaviors in post-war adolescents in northern Uganda.

    PubMed

    Okello, J; Nakimuli-Mpungu, E; Klasen, F; Voss, C; Musisi, S; Broekaert, E; Derluyn, I

    2015-07-15

    We have previously shown that depression symptoms are associated with multiple risk behaviors and that parental attachments are protective against depression symptoms in post-war adolescents. Accumulating literature indicates that low levels of attachment may sensitize individuals to increased multiple risk behaviors when depression symptoms exist. This investigation examined the interactive effects of attachment and depression symptoms on multiple risk behavior. We conducted hierarchical logistic regression analyses to examine the impact of attachment and depression symptoms on multiple risk behavior in our post-war sample of 551 adolescents in Gulu district. Analyses revealed interactive effects for only maternal attachment-by-depression interaction. Interestingly, high levels of maternal attachment exacerbated the relationship between depression symptoms and multiple risk behaviors while low levels of maternal attachment attenuated this relationship. It is possible that this analysis could be biased by a common underlying factor that influences self-reporting and therefore is correlated with each of self-reported attachment security, depressive symptoms, and multiple risk behaviors. These findings suggest that maternal attachment serves as a protective factor at low levels while serving as an additional risk factor at high levels. Findings support and expand current knowledge about the roles that attachment and depression symptoms play in the development of multiple risk behaviors and suggest a more complex etiology for post-war adolescents. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Joint Logistics Commanders’ Workshop on Post Deployment Software Support (PDSS) for Mission-Critical Computer Software. Volume 2. Workshop Proceedings.

    DTIC Science & Technology

    1984-06-01

    exist for the same item, as opposed to separate budget and fund codes for separate but related items. Multiple pro- cedures and fund codes can oe used...funds. If some funds are marked for multiple years and others must be obligated or outlaid witnin one year, contracting for PDSS tasks must be partitioned...Experience: PDSS requires both varied experience factors in multiple dis- ciplines and the sustaining of a critical mass of experience factors and

  9. Stress and multiple sclerosis: A systematic review considering potential moderating and mediating factors and methods of assessing stress.

    PubMed

    Briones-Buixassa, Laia; Milà, Raimon; Mª Aragonès, Josep; Bufill, Enric; Olaya, Beatriz; Arrufat, Francesc Xavier

    2015-07-01

    Research about the effects of stress on multiple sclerosis has yielded contradictory results. This study aims to systematically review the evidence focusing on two possible causes: the role of stress assessment and potential moderating and mediating factors. The Web of Knowledge (MEDLINE and Web of Science), Scopus, and PsycINFO databases were searched for relevant articles published from 1900 through December 2014 using the terms "stress*" AND "multiple sclerosis." Twenty-three articles were included. Studies focused on the effect of stress on multiple sclerosis onset ( n  = 9) were mostly retrospective, and semi-structured interviews and scales yielded the most consistent associations. Studies focused on multiple sclerosis progression ( n  = 14) were mostly prospective, and self-reported diaries yielded the most consistent results. The most important modifying factors were stressor duration, severity, and frequency; cardiovascular reactivity and heart rate; and social support and escitalopram intake. Future studies should consider the use of prospective design with self-reported evaluations and the study of moderators and mediators related to amount of stress and autonomic nervous system reactivity to determine the effects of stress on multiple sclerosis.

  10. Stress and multiple sclerosis: A systematic review considering potential moderating and mediating factors and methods of assessing stress

    PubMed Central

    Briones-Buixassa, Laia; Milà, Raimon; Mª Aragonès, Josep; Bufill, Enric; Olaya, Beatriz; Arrufat, Francesc Xavier

    2015-01-01

    Research about the effects of stress on multiple sclerosis has yielded contradictory results. This study aims to systematically review the evidence focusing on two possible causes: the role of stress assessment and potential moderating and mediating factors. The Web of Knowledge (MEDLINE and Web of Science), Scopus, and PsycINFO databases were searched for relevant articles published from 1900 through December 2014 using the terms “stress*” AND “multiple sclerosis.” Twenty-three articles were included. Studies focused on the effect of stress on multiple sclerosis onset (n = 9) were mostly retrospective, and semi-structured interviews and scales yielded the most consistent associations. Studies focused on multiple sclerosis progression (n = 14) were mostly prospective, and self-reported diaries yielded the most consistent results. The most important modifying factors were stressor duration, severity, and frequency; cardiovascular reactivity and heart rate; and social support and escitalopram intake. Future studies should consider the use of prospective design with self-reported evaluations and the study of moderators and mediators related to amount of stress and autonomic nervous system reactivity to determine the effects of stress on multiple sclerosis. PMID:28070374

  11. New fast DCT algorithms based on Loeffler's factorization

    NASA Astrophysics Data System (ADS)

    Hong, Yoon Mi; Kim, Il-Koo; Lee, Tammy; Cheon, Min-Su; Alshina, Elena; Han, Woo-Jin; Park, Jeong-Hoon

    2012-10-01

    This paper proposes a new 32-point fast discrete cosine transform (DCT) algorithm based on the Loeffler's 16-point transform. Fast integer realizations of 16-point and 32-point transforms are also provided based on the proposed transform. For the recent development of High Efficiency Video Coding (HEVC), simplified quanti-zation and de-quantization process are proposed. Three different forms of implementation with the essentially same performance, namely matrix multiplication, partial butterfly, and full factorization can be chosen accord-ing to the given platform. In terms of the number of multiplications required for the realization, our proposed full-factorization is 3~4 times faster than a partial butterfly, and about 10 times faster than direct matrix multiplication.

  12. Is suicide predictable?

    PubMed

    Seghatoleslam, T; Habi, H; Rashid, R Abdul; Mosavi, N; Asmaee, S; Naseri, A

    2012-01-01

    THE CURRENT STUDY AIMED TO TEST THE HYPOTHESIS: Is suicide predictable? And try to classify the predictive factors in multiple suicide attempts. A cross-sectional study was administered to 223 multiple attempters, women who came to a medical poison centre after a suicide attempt. The participants were young, poor, and single. A Logistic Regression Analiysis was used to classify the predictive factors of suicide. Women who had multiple suicide attempts exhibited a significant tendency to attempt suicide again. They had a history for more than two years of multiple suicide attempts, from three to as many as 18 times, plus mental illnesses such as depression and substance abuse. They also had a positive history of mental illnesses. Results indicate that contributing factors for another suicide attempt include previous suicide attempts, mental illness (depression), or a positive history of mental illnesses in the family affecting them at a young age, and substance abuse.

  13. Structural invariance of multiple intelligences, based on the level of execution.

    PubMed

    Almeida, Leandro S; Prieto, María Dolores; Ferreira, Arístides; Ferrando, Mercedes; Ferrandiz, Carmen; Bermejo, Rosario; Hernández, Daniel

    2011-11-01

    The independence of multiple intelligences (MI) of Gardner's theory has been debated since its conception. This article examines whether the one- factor structure of the MI theory tested in previous studies is invariant for low and high ability students. Two hundred ninety-four children (aged 5 to 7) participated in this study. A set of Gardner's Multiple Intelligence assessment tasks based on the Spectrum Project was used. To analyze the invariance of a general dimension of intelligence, the different models of behaviours were studied in samples of participants with different performance on the Spectrum Project tasks with Multi-Group Confirmatory Factor Analysis (MGCFA). Results suggest an absence of structural invariance in Gardner's tasks. Exploratory analyses suggest a three-factor structure for individuals with higher performance levels and a two-factor structure for individuals with lower performance levels.

  14. Neutron Detector Signal Processing to Calculate the Effective Neutron Multiplication Factor of Subcritical Assemblies

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

    Talamo, Alberto; Gohar, Yousry

    2016-06-01

    This report describes different methodologies to calculate the effective neutron multiplication factor of subcritical assemblies by processing the neutron detector signals using MATLAB scripts. The subcritical assembly can be driven either by a spontaneous fission neutron source (e.g. californium) or by a neutron source generated from the interactions of accelerated particles with target materials. In the latter case, when the particle accelerator operates in a pulsed mode, the signals are typically stored into two files. One file contains the time when neutron reactions occur and the other contains the times when the neutron pulses start. In both files, the timemore » is given by an integer representing the number of time bins since the start of the counting. These signal files are used to construct the neutron count distribution from a single neutron pulse. The built-in functions of MATLAB are used to calculate the effective neutron multiplication factor through the application of the prompt decay fitting or the area method to the neutron count distribution. If the subcritical assembly is driven by a spontaneous fission neutron source, then the effective multiplication factor can be evaluated either using the prompt neutron decay constant obtained from Rossi or Feynman distributions or the Modified Source Multiplication (MSM) method.« less

  15. Organizational Predictors of Staff Stress, Satisfaction, and Intended Turnover in a Service for People with Multiple Disabilities.

    ERIC Educational Resources Information Center

    Hatton, Chris; Emerson, Eric

    1993-01-01

    Questionnaire data were collected from 64 direct-care staff members in a residential facility for people with multiple disabilities. Path analyses identified factors predicting levels of perceived stress, overall job satisfaction, overall life satisfaction, and perceived likelihood of leaving the organization. Factors included staff support, job…

  16. Multiple-bolted joints in wood members : a literature review

    Treesearch

    Peter James Moss

    1997-01-01

    This study reviewed the literature on experimental and analytical research for the connection of wood members using multiple laterally loaded bolts. From this, the influence of geometric factors were ascertained, such as staggered and aligned fasteners, optimum fastener configurations, row factors and length-to-diameter bolt ratios, spacing, end and edge distances, and...

  17. Bidirectional Associations in Multiplication Memory: Conditions of Negative and Positive Transfer

    ERIC Educational Resources Information Center

    Campbell, Jamie I. D.; Robert, Nicole D.

    2008-01-01

    A variety of experimental evidence indicates that the memory representation for multiplication facts (e.g., 6 [times] 9 = 54) incorporates bidirectional links with a forward association from factors to product and a reverse association from product to factors. Surprisingly, the authors did not find evidence in Experiment 1 of facilitative…

  18. Primary Factors Related to Multiple Placements for Children in Out-of-Home Care

    ERIC Educational Resources Information Center

    Eggertsen, Lars

    2008-01-01

    Using an ecological framework, this study identified which factors related to out-of-home placements significantly influenced multiple placements for children in Utah during 2000, 2001, and 2002. Multinomial logistic regression statistical procedures and a geographical information system (GIS) were used to analyze the data. The final model…

  19. The Use of Multiple Regression Models to Determine if Conjoint Analysis Should Be Conducted on Aggregate Data.

    ERIC Educational Resources Information Center

    Fraas, John W.; Newman, Isadore

    1996-01-01

    In a conjoint-analysis consumer-preference study, researchers must determine whether the product factor estimates, which measure consumer preferences, should be calculated and interpreted for each respondent or collectively. Multiple regression models can determine whether to aggregate data by examining factor-respondent interaction effects. This…

  20. Risk factors for retinal breaks in patients with symptom of floaters.

    PubMed

    Singalavanija, Apichart; Amornrattanapan, Chutiwan; Nitiruangjarus, Kanjanee; Tongsai, Sasima

    2010-06-01

    To identify the risk factors of retinal breaks in patients with the symptom of floaters, and to determine the association between those risk factors and retinal breaks. A retrospective analytic study of 184 patients (55 males and 129 females) that included 220 eyes was conducted. Patient information such as age, symptoms (multiple floaters, flashing), duration of symptom, refractive error, history of cataract surgery, family history of retinal detachment, and complete eye examination were recorded. The patients were divided into two groups, the first group (control group) had symptoms of floaters and no retinal breaks, the second group (retinal breaks group) had symptoms of floaters with retinal breaks. Chi-square test, and the multiple logistic regression were used for statistical analysis. Two hundred twenty eyes, 175 eyes of the control group and 45 eyes of the retinal breaks group were examined and included in this study. The multiple logistic regression analysis revealed that patients with multiple floaters, and floaters and flashing increased the risk of retinal breaks to 5.8 and 4.3 times, respectively, when compared to patients with single floater or floaters alone. Lattice degeneration increased the risk of retinal breaks to 5.9 times when compared to eyes that did not have lattice degeneration. Multiple floaters, flashing and lattice degeneration are risk factors of retinal breaks in patients with symptoms of floaters. Therefore, it is important for the ophthalmologists to be aware of these risk factors and the patients at risk should have follow-up examinations.

  1. Factor analysis and multiple regression between topography and precipitation on Jeju Island, Korea

    NASA Astrophysics Data System (ADS)

    Um, Myoung-Jin; Yun, Hyeseon; Jeong, Chang-Sam; Heo, Jun-Haeng

    2011-11-01

    SummaryIn this study, new factors that influence precipitation were extracted from geographic variables using factor analysis, which allow for an accurate estimation of orographic precipitation. Correlation analysis was also used to examine the relationship between nine topographic variables from digital elevation models (DEMs) and the precipitation in Jeju Island. In addition, a spatial analysis was performed in order to verify the validity of the regression model. From the results of the correlation analysis, it was found that all of the topographic variables had a positive correlation with the precipitation. The relations between the variables also changed in accordance with a change in the precipitation duration. However, upon examining the correlation matrix, no significant relationship between the latitude and the aspect was found. According to the factor analysis, eight topographic variables (latitude being the exception) were found to have a direct influence on the precipitation. Three factors were then extracted from the eight topographic variables. By directly comparing the multiple regression model with the factors (model 1) to the multiple regression model with the topographic variables (model 3), it was found that model 1 did not violate the limits of statistical significance and multicollinearity. As such, model 1 was considered to be appropriate for estimating the precipitation when taking into account the topography. In the study of model 1, the multiple regression model using factor analysis was found to be the best method for estimating the orographic precipitation on Jeju Island.

  2. Multiple Mechanisms are Responsible for Transactivation of the Epidermal Growth Factor Receptor in Mammary Epithelial Cells

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

    Rodland, Karin D.; Bollinger, Nikki; Ippolito, Danielle L.

    2008-11-14

    REVIEW ENTIRE DOCUMENT AT: https://pnlweb.pnl.gov/projects/bsd/ERICA%20Manuscripts%20for%20Review/KD%20Rodland%20D7E80/HMEC_transactivation_ms01_15+Figs.pdf ABSTRACT: Using a single nontransformed strain of human mammary epithelial cells, we found that the ability of multiple growth factors and cytokines to induce ERK phosphorylation was dependent on EGFR activity. These included lysophosphatidic acid (LPA), uridine triphosphate, growth hormone, vascular endothelial growth factor, insulin-like growth factor-1 (IGF-1), and tumor necrosis factoralpha. In contrast, hepatocyte growth factor could stimulate ERK phosphorylation independent of EGFR activity...

  3. Chronic periodontitis with multiple risk factor syndrome: a case report.

    PubMed

    Shimoe, Masayuki; Yamamoto, Tadashi; Iwamoto, Yoshihiro; Shiomi, Nobuyuki; Maeda, Hiroshi; Nishimura, Fusanori; Takashiba, Shogo

    2011-07-01

    Multiple risk factor syndrome is a clustering of cardiovascular risk factors, such as diabetes, dyslipidemia, hypertension, and obesity associated epidemiologically with insulin resistance. This report describes the clinical course of a patient suffering from severe periodontitis with multiple risk factor syndrome, and discusses the association between periodontal infection and systemic health. The patient had a history of type 2 diabetes, dyslipidemia, and hypertension for over 10 years. At baseline, her hemoglobin A1 c was 8.1%. However, she had no diabetic complications except periodontitis. The IgG antibody titers against Porphyromonas gingivalis FDC 381 and SU63 were elevated above the mean of healthy subjects +2 standard deviations. Intensive periodontal treatment, including periodontal surgery, was performed to reduce periodontal infection and bacteremia. Her systemic and periodontal conditions were evaluated longitudinally for 10 years. Following periodontal treatment, antibody titers against Porphyromonas gingivalis and hemoglobin A1c values were significantly improved. The other clinical data and medication for her systemic condition also remained stable during supportive periodontal therapy. However, she developed myocardial infarction, and showed continuous deterioration of hemoglobin A1 c level and periodontitis. The long-term clustering of risk factors, such as diabetes, dyslipidemia, hypertension, and periodontitis, are associated with the development of myocardial infarction. Treatment of systemic conditions in combination with comprehensive periodontal treatment is important in management of patients with multiple risk factor syndrome.

  4. [Establishment of multiple regression model for virulence factors of Saccharomyces albicans by random amplified polymorphic DNA bands].

    PubMed

    Liu, Qi; Wu, Youcong; Yuan, Youhua; Bai, Li; Niu, Kun

    2011-12-01

    To research the relationship between the virulence factors of Saccharomyces albicans (S. albicans) and the random amplified polymorphic DNA (RAPD) bands of them, and establish the regression model by multiple regression analysis. Extracellular phospholipase, secreted proteinase, ability to generate germ tubes and adhere to oral mucosal cells of 92 strains of S. albicans were measured in vitro; RAPD-polymerase chain reaction (RAPD-PCR) was used to get their bands. Multiple regression for virulence factors of S. albicans and RAPD-PCR bands was established. The extracellular phospholipase activity was associated with 4 RAPD bands: 350, 450, 650 and 1 300 bp (P < 0.05); secreted proteinase activity of S. albicans was associated with 2 bands: 350 and 1 200 bp (P < 0.05); the ability of germ tube produce was associated with 2 bands: 400 and 550 bp (P < 0.05). Some RAPD bands will reflect the virulence factors of S. albicans indirectly. These bands would contain some important messages for regulation of S. albicans virulence factors.

  5. Controlled Release Strategies for Bone, Cartilage, and Osteochondral Engineering—Part II: Challenges on the Evolution from Single to Multiple Bioactive Factor Delivery

    PubMed Central

    Santo, Vítor E.; Mano, João F.; Reis, Rui L.

    2013-01-01

    The development of controlled release systems for the regeneration of bone, cartilage, and osteochondral interface is one of the hot topics in the field of tissue engineering and regenerative medicine. However, the majority of the developed systems consider only the release of a single growth factor, which is a limiting step for the success of the therapy. More recent studies have been focused on the design and tailoring of appropriate combinations of bioactive factors to match the desired goals regarding tissue regeneration. In fact, considering the complexity of extracellular matrix and the diversity of growth factors and cytokines involved in each biological response, it is expected that an appropriate combination of bioactive factors could lead to more successful outcomes in tissue regeneration. In this review, the evolution on the development of dual and multiple bioactive factor release systems for bone, cartilage, and osteochondral interface is overviewed, specifically the relevance of parameters such as dosage and spatiotemporal distribution of bioactive factors. A comprehensive collection of studies focused on the delivery of bioactive factors is also presented while highlighting the increasing impact of platelet-rich plasma as an autologous source of multiple growth factors. PMID:23249320

  6. Multiple Intelligence Levels of Physical Education and Sports School Students

    ERIC Educational Resources Information Center

    Ekici, Summani

    2011-01-01

    The purpose of this research is to analyze the multiple intelligence levels of academies of physical education and sports students according to some demographic factors. To obtain data about multiple intelligence levels in the research, the multiple intelligence inventory, developed by Ozden (2003), was applied to a total of 1.199 students, of…

  7. Multiple Languages and the School Curriculum: Experiences from Tanzania

    ERIC Educational Resources Information Center

    Mushi, Selina Lesiaki Prosper

    2012-01-01

    This is a research report on children's use of multiple languages and the school curriculum. The study explored factors that trigger use of, and fluency in, multiple languages; and how fluency in multiple languages relates to thought processes and school performance. Advantages and disadvantages of using only one of the languages spoken were…

  8. Return to the Primary Acute Care Service Among Patients With Multiple Myeloma on an Acute Inpatient Rehabilitation Unit.

    PubMed

    Fu, Jack B; Lee, Jay; Shin, Ben C; Silver, Julie K; Smith, Dennis W; Shah, Jatin J; Bruera, Eduardo

    2017-06-01

    Pancytopenia, immunosuppression, and other factors may place patients with multiple myeloma at risk for medical complications. These patients often require inpatient rehabilitation. No previous studies have looked at risk factors for return to the primary acute care service of this patient population. To determine the percentage of and factors associated with return to the primary acute care service of multiple myeloma rehabilitation inpatients. Retrospective review. Acute inpatient rehabilitation unit within a National Cancer Institute Comprehensive Cancer Center. All patients with multiple myeloma admitted to the inpatient rehabilitation unit between March 1, 2004, and February 28, 2015. Return to the primary acute care service was analyzed with demographic information, multiple myeloma characteristics, medications, laboratory values, and hospital admission characteristics. One hundred forty-three inpatient rehabilitation admissions were found during the study period. After we removed multiple admissions of the same patients and planned transfers to the primary acute care service, 122 admissions were analyzed. Thirty-two (26%) patients transferred back to the primary acute care service for unplanned reasons. Multivariate analysis revealed male gender and thrombocytopenia as significantly associated with return to the primary acute care service. The median survival of patients who transferred back to the inpatient primary acute care service was 180 days versus 550 days for those who did not (P < .001). Because of their medical fragility, clinicians caring for rehabilitation inpatients with multiple myeloma should maintain close contact with the primary oncology service. Factors associated with an increased risk of transfer back to the primary acute care service include male gender and thrombocytopenia. IV. Copyright © 2017 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  9. Effect of aerobic interval training on serum IL-10, TNFα, and adipokines levels in women with multiple sclerosis: possible relations with fatigue and quality of life.

    PubMed

    Mokhtarzade, Motahare; Ranjbar, Rouholah; Majdinasab, Nastaran; Patel, Darpan; Molanouri Shamsi, Mehdieh

    2017-08-01

    Multiple sclerosis is associated with immune system dysfunction and chronic inflammation; however, possible relations between immunologic and metabolic factors and some psychological indexes such as fatigue and quality of life, especially in relation to exercise training, have not yet been investigated. The present study was designed to investigate the effect of aerobic interval training on interleukin-10/tumor necrosis factor ratio and adipokine (leptin and adiponectin) concentrations in women with multiple sclerosis. Furthermore, the relationship between these factors with fatigue and quality of life were assessed. Forty women with multiple sclerosis (Expanded Disability Status Scale ≤3) were randomized into either a non-exercising control or training group. The training group performed 8-weeks of upper and lower limb aerobic interval training. Serum concentrations of tumor necrosis factorα, interleukin-10, leptin, and adiponectin were measured before and after the 8-week intervention. Moreover, antropometric measures and measures for fatigue and quality of life were determined at the onset of and after exercise training. The results revealed that leptin and tumor necrosis factorα levels significantly decreased subsequent to the aerobic interval training. Although blood adiponectin levels considerably increased in the training group, interleukin-10 and interleukin-10/tumor necrosis factorα ratio underwent no substantial change after the exercise training. In addition, the aerobic interval training was associated with improvement in fatigue, quality of life, and maximal oxygen consumption. Our findings suggested that aerobic interval training can be an effective strategy for managing the immune system at least by its significant impact on inflammatory cytokines and adipokines levels in women with multiple sclerosis. Additionally, this positive impact improved fatigue and adipose tissue indicators.

  10. Renal Protective Role of Xiexin Decoction with Multiple Active Ingredients Involves Inhibition of Inflammation through Downregulation of the Nuclear Factor-κB Pathway in Diabetic Rats

    PubMed Central

    Wu, Jia-sheng; Shi, Rong; Zhong, Jie; Lu, Xiong; Ma, Bing-liang; Wang, Tian-ming; Zan, Bin; Ma, Yue-ming; Cheng, Neng-neng; Qiu, Fu-rong

    2013-01-01

    In Chinese medicine, Xiexin decoction (XXD) has been used for the clinical treatment of diabetes for at least 1700 years. The present study was conducted to investigate the effective ingredients of XXD and their molecular mechanisms of antidiabetic nephropathy in rats. Rats with diabetes induced by high-fat diet and streptozotocin were treated with XXD extract for 12 weeks. XXD significantly improved the glucolipid metabolism disorder, attenuated albuminuria and renal pathological changes, reduced renal advanced glycation end-products, inhibited receptor for advanced glycation end-product and inflammation factors expression, suppressed renal nuclear factor-κB pathway activity, and downregulated renal transforming growth factor-β1. The concentrations of multiple components in plasma from XXD were determined by liquid chromatography and tandem mass spectrometry. Pharmacokinetic/pharmacodynamic analysis using partial least square regression revealed that 8 ingredients of XXD were responsible for renal protective effects via actions on multiple molecular targets. Our study suggests that the renal protective role of XXD with multiple effective ingredients involves inhibition of inflammation through downregulation of the nuclear factor-κB pathway, reducing renal advanced glycation end-products and receptor for advanced glycation end-product in diabetic rats. PMID:23935673

  11. A Multiple Risk Factors Model of the Development of Aggression among Early Adolescents from Urban Disadvantaged Neighborhoods

    ERIC Educational Resources Information Center

    Kim, Sangwon; Orpinas, Pamela; Kamphaus, Randy; Kelder, Steven H.

    2011-01-01

    This study empirically derived a multiple risk factors model of the development of aggression among middle school students in urban, low-income neighborhoods, using Hierarchical Linear Modeling (HLM). Results indicated that aggression increased from sixth to eighth grade. Additionally, the influences of four risk domains (individual, family,…

  12. Physical and Cognitive-Affective Factors Associated with Fatigue in Individuals with Fibromyalgia: A Multiple Regression Analysis

    ERIC Educational Resources Information Center

    Muller, Veronica; Brooks, Jessica; Tu, Wei-Mo; Moser, Erin; Lo, Chu-Ling; Chan, Fong

    2015-01-01

    Purpose: The main objective of this study was to determine the extent to which physical and cognitive-affective factors are associated with fibromyalgia (FM) fatigue. Method: A quantitative descriptive design using correlation techniques and multiple regression analysis. The participants consisted of 302 members of the National Fibromyalgia &…

  13. Technical and Practical Issues in the Structure and Clinical Invariance of the Wechsler Scales: A Rejoinder to Commentaries

    ERIC Educational Resources Information Center

    Weiss, Lawrence G.; Keith, Timothy Z.; Zhu, Jianjun; Chen, Hsinyi

    2013-01-01

    This discussion article addresses issues related to expansion of the Wechsler model from four to five factors; multiple broad CHC abilities measured by the Arithmetic subtest; advantages and disadvantages of including complex tasks requiring integration of multiple broad abilities when measuring intelligence; limitations of factor analysis, which…

  14. Care delivery for Filipino Americans using the Neuman systems model.

    PubMed

    Angosta, Alona D; Ceria-Ulep, Clementina D; Tse, Alice M

    2014-04-01

    Filipino Americans are at risk of coronary heart disease due to the presence of multiple cardiometabolic factors. Selecting a framework that addresses the factors leading to coronary heart disease is vital when providing care for this population. The Neuman systems model is a comprehensive and wholistic framework that offers an innovative method of viewing clients, their families, and the healthcare system across multiple dimensions. Using the Neuman systems model, advanced practice nurses can develop and implement interventions that will help reduce the potential cardiovascular problems of clients with multiple risk factors. The authors in this article provides insight into the cardiovascular health of Filipino Americans and has implications for nurses and other healthcare providers working with various Southeast Asian groups in the United States.

  15. Role of Proangiogenic Factors in Immunopathogenesis of Multiple Sclerosis.

    PubMed

    Hamid, Kabir Magaji; Mirshafiey, Abbas

    2016-02-01

    Angiogenesis is a complex and balanced process in which new blood vessels form from preexisting ones by sprouting, splitting, growth and remodeling. This phenomenon plays a vital role in many physiological and pathological processes. However, the disturbance in physiological process can play a role in pathogenesis of some chronic inflammatory diseases, including multiple sclerosis (MS) in human and its animal model. Although the relation between abnormal blood vessels and MS lesions was established in previous studies, but the role of pathological angiogenesis remains unclear. In this study, the link between proangiogenic factors and multiple sclerosis pathogenesis was examined by conducting a systemic review. Thus we searched the English medical literature via PubMed, ISI web of knowledge, Medline and virtual health library (VHL) databases. In this review, we describe direct and indirect roles of some proangiogenic factors in MS pathogenesis and report the association of these factors with pathological and inflammatory angiogenesis.

  16. Fuel Fraction Analysis of 500 MWth Gas Cooled Fast Reactor with Nitride (UN-PuN) Fuel without Refueling

    NASA Astrophysics Data System (ADS)

    Dewi Syarifah, Ratna; Su'ud, Zaki; Basar, Khairul; Irwanto, Dwi

    2017-01-01

    Nuclear Power Plant (NPP) is one of candidates which can support electricity demand in the world. The Generation IV NPP has fourth main objective, i.e. sustainability, economics competitiveness, safety and reliability, and proliferation and physical protection. One of Gen-IV reactor type is Gas Cooled Fast Reactor (GFR). In this study, the analysis of fuel fraction in small GFR with nitride fuel has been done. The calculation was performed by SRAC code, both Pij and CITATION calculation. SRAC2002 system is a code system applicable to analyze the neutronics of variety reactor type. And for the data library used JENDL-3.2. The step of SRAC calculation is fuel pin calculated by Pij calculation until the data homogenized, after it homogenized we calculate core reactor. The variation of fuel fraction is 40% up to 65%. The optimum design of 500MWth GFR without refueling with 10 years burn up time reach when radius F1:F2:F3 = 50cm:30cm:30cm and height F1:F2:F3 = 50cm:40cm:30cm, variation percentage Plutonium in F1:F2:F3 = 7%:10%:13%. The optimum fuel fraction is 41% with addition 2% Plutonium weapon grade mix in the fuel. The excess reactivity value in this case 1.848% and the k-eff value is 1.01883. The high burn up reached when the fuel fraction is low. In this study 41% fuel fraction produce faster fissile fuel, so it has highest burn-up level than the other fuel fraction.

  17. Fabrication and magnetic properties of structure-tunable Co2FeGa-SiO2 Heusler nanocompounds

    NASA Astrophysics Data System (ADS)

    Xu, Yunli; Yang, Dongchao; Luo, Zhaochu; Wu, Fengyu; Chen, Cheng; Liu, Min; Yi, Lizhi; Piao, Hong-Guang; Yu, Guanghua

    2018-05-01

    Co2FeGa-SiO2 nanocompounds were chemically synthesized by using SBA-15 as template, which has the L21 Heusler phase. The reactants comprised CoCl2 . 6H2O, Fe(NO3)3 . 9H2O and Ga(NO3) . xH2O with the addition of SBA-15 with different contents. The structure and morphology of the product were controlled by modulating the ratio of reactants to templates. After high-temperature annealing under H2 atmosphere and the removal of the template, the Co2FeGa nanowires, which are of about 125˜200 nm length, 4˜7 nm width and the length-to-width ratio of about 30 were observed by transmission electron microscope. The structure and component of the nanowires were confirmed by selected area electron diffraction, X-ray diffraction and energy-dispersive X-ray spectroscopy, respectively. The magnetic test showed that the saturation magnetization (Ms) was 87.5 emu/g for the Co2FeGa nanowires, and the Curie temperature was higher than 380K. The effective anisotropy constant Keff=4.196 × 105 J/m3 was calculated using magnetization curve, which is below the value of bulk Co2FeGa 6.54 × 105 J/m3. The dynamic magnetic properties study performed by ferromagnetic resonance indicated that the Gilbert damping coefficient α were about 0.1944-0.0288 for different samples. The high damping coefficient makes the nanocomposites promising to be used as a microwave absorber in the GHz band.

  18. Perpendicular magnetic anisotropy in Mo/Co2FeAl0.5Si0.5/MgO/Mo multilayers with optimal Mo buffer layer thickness

    NASA Astrophysics Data System (ADS)

    Saravanan, L.; Raja, M. Manivel; Prabhu, D.; Pandiyarasan, V.; Ikeda, H.; Therese, H. A.

    2018-05-01

    Perpendicular Magnetic Anisotropy (PMA) was realized in as-deposited Mo(10)/Co2FeAl0.5Si0.5(CFAS)(3)/MgO(0.5)/Mo multilayer stacks with large perpendicular magnetic anisotropy energy (Keff). PMA of this multilayer is found to be strongly dependent on the thickness of the individual CFAS (tCFAS), Mo (tMo) and MgO (tMgO) layers and annealing temperatures. The interactions at the Mo/CFAS/MgO interfaces are critical to induce PMA and are tuned by the interfacial oxidation. The major contribution to PMA is due to iron oxide at the CFAS/MgO interface. X-ray diffraction (XRD) and infrared spectroscopic (FT-IR) studies further ascertain this. However, an adequate oxidation of MgO and the formation of (0 2 4) and (0 1 8) planes of α-Fe2O3 at the optimal Mo buffer layer thickness is mainly inducing PMA in Mo/CFAS/MgO/Mo stack. Microstructural changes in the films are observed by atomic force microscopy (AFM). X-ray photoelectron spectroscopy (XPS) demonstrates the oxidation of CFAS/MgO interface and the formation of Fe-O bonds confirming that the real origin of PMA in Mo/CFAS/MgO is due to hybridization of Fe (3dz2) and O (2pz) orbitals and the resulted spin-orbit interaction at their interface. The half-metallic nature CFAS with Mo layer exhibiting PMA can be a potential candidate as p-MTJs electrodes for the new generation spintronic devices.

  19. Synthesis, characterization and magneto optical properties of BaBixLaxYxFe12-3xO19 (0.0≤x≤0.33) hexaferrites

    NASA Astrophysics Data System (ADS)

    Güner, S.; Auwal, I. A.; Baykal, A.; Sözeri, H.

    2016-10-01

    BaBixLaxYxFe12-3xO19 (0.0≤x≤0.33) hexaferrites were synthesized by sol-gel autocombustion method and the effects of Bi, La, Y substitutions on structural, magneto-optical properties of barium hexaferrite were investigated. X-ray diffraction (XRD), Scanning electron microscopy (SEM), Vibrating sample magnetometer (VSM), and Percent diffuse reflectance spectroscopy (DR %), were used to study the physical properties. XRD peaks showed pure single phase of hexagonal ferrites and the average crystallite size varies in a range of 42.35-49.90 nm. Room temperature (RT) specific magnetization (σ-H) data revealed the strong ferromagnetic nature of hexaferrite with remanant specific magnetization (σr) in the range of 29.9-34.6 Am2/kg and extrapolated specific saturation magnetization (σs) in the range 53.69-67.42 Am2/kg. The maximum coercive field (Hc) of 3.812×105 A/m (belongs to BaFe12O19) decreases to minimum 2.177×105 A/m with increasing ion substitution. Magnetic anisotropy was confirmed as uniaxial and effective anisotropy constant (Keff) takes values between 2.532×105 J/m3 and 3.105×105 J/m3. The anisotropy field (Ha) around 1.6 T revealed that all samples are magnetically hard materials. The Tauc graphs were plotted to estimate the direct optical energy band gap (Eg) of hexaferrite. The Eg values decreased from 1.88 eV to 1.69 eV with increasing Bi, La, Y compositions.

  20. A Comparison of Monte Carlo and Deterministic Solvers for keff and Sensitivity Calculations

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

    Haeck, Wim; Parsons, Donald Kent; White, Morgan Curtis

    Verification and validation of our solutions for calculating the neutron reactivity for nuclear materials is a key issue to address for many applications, including criticality safety, research reactors, power reactors, and nuclear security. Neutronics codes solve variations of the Boltzmann transport equation. The two main variants are Monte Carlo versus deterministic solutions, e.g. the MCNP [1] versus PARTISN [2] codes, respectively. There have been many studies over the decades that examined the accuracy of such solvers and the general conclusion is that when the problems are well-posed, either solver can produce accurate results. However, the devil is always in themore » details. The current study examines the issue of self-shielding and the stress it puts on deterministic solvers. Most Monte Carlo neutronics codes use continuous-energy descriptions of the neutron interaction data that are not subject to this effect. The issue of self-shielding occurs because of the discretisation of data used by the deterministic solutions. Multigroup data used in these solvers are the average cross section and scattering parameters over an energy range. Resonances in cross sections can occur that change the likelihood of interaction by one to three orders of magnitude over a small energy range. Self-shielding is the numerical effect that the average cross section in groups with strong resonances can be strongly affected as neutrons within that material are preferentially absorbed or scattered out of the resonance energies. This affects both the average cross section and the scattering matrix.« less

  1. Analytical approximations for effective relative permeability in the capillary limit

    NASA Astrophysics Data System (ADS)

    Rabinovich, Avinoam; Li, Boxiao; Durlofsky, Louis J.

    2016-10-01

    We present an analytical method for calculating two-phase effective relative permeability, krjeff, where j designates phase (here CO2 and water), under steady state and capillary-limit assumptions. These effective relative permeabilities may be applied in experimental settings and for upscaling in the context of numerical flow simulations, e.g., for CO2 storage. An exact solution for effective absolute permeability, keff, in two-dimensional log-normally distributed isotropic permeability (k) fields is the geometric mean. We show that this does not hold for krjeff since log normality is not maintained in the capillary-limit phase permeability field (Kj=k·krj) when capillary pressure, and thus the saturation field, is varied. Nevertheless, the geometric mean is still shown to be suitable for approximating krjeff when the variance of ln⁡k is low. For high-variance cases, we apply a correction to the geometric average gas effective relative permeability using a Winsorized mean, which neglects large and small Kj values symmetrically. The analytical method is extended to anisotropically correlated log-normal permeability fields using power law averaging. In these cases, the Winsorized mean treatment is applied to the gas curves for cases described by negative power law exponents (flow across incomplete layers). The accuracy of our analytical expressions for krjeff is demonstrated through extensive numerical tests, using low-variance and high-variance permeability realizations with a range of correlation structures. We also present integral expressions for geometric-mean and power law average krjeff for the systems considered, which enable derivation of closed-form series solutions for krjeff without generating permeability realizations.

  2. Factors affecting dignity of patients with multiple sclerosis.

    PubMed

    Sharifi, Simin; Borhani, Fariba; Abbaszadeh, Abbas

    2016-12-01

    MS is one of the most common chronic diseases of the nervous system. Apart from disease progression, other complications such as unemployment, separation and divorce could potentially threat patients' dignity. Most of the previous studies have been done of maintaining patients' dignity in interaction with healthcare team, but studies on affecting factors of dignity in chronic patients in the society and in interaction with usual people are scarce. We aimed to investigate factors affecting dignity of Iranian patients with MS in daily living and in interaction of them with the society. In this qualitative study, 13 patients with multiple sclerosis were chosen by purposive sampling and semi-structured interviews were conducted until data saturation. The study was done in Tehran, the capital city of Iran. Factors affecting dignity were classified as 'personal factors' and 'social factors'. Personal factors consist of the following subcategories: patients' communication with self, patients' knowledge, patients' values and beliefs and patients' resources. Social factors include others' communication with patients, social knowledge, social values and beliefs and social resources. Multiple personal and social factors interfere in perceived patient dignity. In fact, interaction between personal and social factors can be influential in final perceived dignity. By focusing on whole aspects of the patients' lives, we can identify dignity-promoting or dignity-threatening factors and help patients maintain their dignity by taking appropriate measures for moderating threatening factors and improving dignity enhancing ones. © 2016 Nordic College of Caring Science.

  3. Multiple sclerosis: Pregnancy and women's health issues.

    PubMed

    Mendibe Bilbao, M; Boyero Durán, S; Bárcena Llona, J; Rodriguez-Antigüedad, A

    2016-08-18

    The course of multiple sclerosis (MS) is influenced by sex, pregnancy and hormonal factors. To analyse the influence of the above factors in order to clarify the aetiopathogenic mechanisms involved in the disease. We conducted a comprehensive review of scientific publications in the PubMed database using a keyword search for 'multiple sclerosis', 'MS', 'EAE', 'pregnancy', 'hormonal factors', 'treatment', and related terms. We reviewed the advances presented at the meeting held by the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) in March 2013 in London, as well as recommendations by international experts. We provide recommendations for counselling and treating women with MS prior to and during pregnancy and after delivery. Current findings on the effects of treatment on the mother, fetus, and newborn are also presented. We issue recommendations for future research in order to address knowledge gaps and clarify any inconsistencies in currently available data. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Risk factors for fecal colonization with multiple distinct strains of Escherichia coli among long-term care facility residents.

    PubMed

    Lautenbach, Ebbing; Tolomeo, Pam; Black, Nicole; Maslow, Joel N

    2009-05-01

    Of 49 long-term care facility residents, 21 (43%) were colonized with 2 or more distinct strains of Escherichia coli. There were no significant risk factors for colonization with multiple strains of E. coli. These results suggest that future efforts to efficiently identify the diversity of colonizing strains will be challenging.

  5. Risk Factors for Fecal Colonization with Multiple Distinct Strains of Escherichia coli Among Long-Term Care Facility Residents

    PubMed Central

    Lautenbach, Ebbing; Tolomeo, Pam; Black, Nicole; Maslow, Joel N.

    2009-01-01

    Of 49 long-term care facility residents, 21 (43%) were colonized with two or more distinct strains of Escherichia coli. There were no significant risk factors for colonization with multiple strains of E. coli. These results suggest future efforts to efficiently identify diversity of colonizing strains will be challenging. PMID:19292660

  6. Multiple-Group Confirmatory Factor Analysis in R--A Tutorial in Measurement Invariance with Continuous and Ordinal Indicators

    ERIC Educational Resources Information Center

    Hirschfeld, Gerrit; von Brachel, Ruth

    2014-01-01

    Multiple-group confirmatory factor analysis (MG-CFA) is among the most productive extensions of structural equation modeling. Many researchers conducting cross-cultural or longitudinal studies are interested in testing for measurement and structural invariance. The aim of the present paper is to provide a tutorial in MG-CFA using the freely…

  7. Adaptation of a Counseling Intervention to Address Multiple Cancer Risk Factors among Overweight/Obese Latino Smokers

    ERIC Educational Resources Information Center

    Castro, Yessenia; Fernández, Maria E.; Strong, Larkin L.; Stewart, Diana W.; Krasny, Sarah; Hernandez Robles, Eden; Heredia, Natalia; Spears, Claire A.; Correa-Fernández, Virmarie; Eakin, Elizabeth; Resnicow, Ken; Basen-Engquist, Karen; Wetter, David W.

    2015-01-01

    More than 60% of cancer-related deaths in the United States are attributable to tobacco use, poor nutrition, and physical inactivity, and these risk factors tend to cluster together. Thus, strategies for cancer risk reduction would benefit from addressing multiple health risk behaviors. We adapted an evidence-based intervention grounded in social…

  8. Evidence for transverse momentum and pseudorapidity dependent event plane fluctuations in PbPb and pPb collisions

    DOE PAGES

    Khachatryan, Vardan

    2015-09-22

    A systematic study of the factorization of long-range azimuthal two-particle correlations into a product of single-particle anisotropies is presented as a function of p T and η of both particles and as a function of the particle multiplicity in PbPb and pPb collisions. The data were taken with the CMS detector for PbPb collisions at √s NN=2.76 TeV and pPb collisions at √s NN=5.02 TeV, covering a very wide range of multiplicity. Factorization is observed to be broken as a function of both particle p T and η. When measured with particles of different p T, the magnitude of themore » factorization breakdown for the second Fourier harmonic reaches 20% for very central PbPb collisions but decreases rapidly as the multiplicity decreases. The data are consistent with viscous hydrodynamic predictions, which suggest that the effect of factorization breaking is mainly sensitive to the initial-state conditions rather than to the transport properties (e.g., shear viscosity) of the medium. The factorization breakdown is also computed with particles of different η. The effect is found to be weakest for mid-central PbPb events but becomes larger for more central or peripheral PbPb collisions, and also for very-high-multiplicity pPb collisions. The η-dependent factorization data provide new insights to the longitudinal evolution of the medium formed in heavy ion collisions.« less

  9. Care Delivery for Filipino Americans Using the Neuman Systems Model

    PubMed Central

    Angosta, Alona D.; Ceria-Ulep, Clementina D.; Tse, Alice M.

    2016-01-01

    Filipino Americans are at risk of coronary heart disease due to the presence of multiple cardiometabolic factors. Selecting a framework that addresses the factors leading to coronary heart disease is vital when providing care for this population. The Neuman systems model is a comprehensive and wholistic framework that offers an innovative method of viewing clients, their families, and the healthcare system across multiple dimensions. Using the Neuman systems model, advanced practice nurses can develop and implement interventions that will help reduce the potential cardiovascular problems of clients with multiple risk factors. The authors in this article provides insight into the cardiovascular health of Filipino Americans and has implications for nurses and other healthcare providers working with various Southeast Asian groups in the United States. PMID:24740949

  10. Ecological correlates of multiple sexual partnerships among adolescents and young adults in urban Cape Town: a cumulative risk factor approach.

    PubMed

    Muchiri, Evans; Odimegwu, Clifford; Banda, Pamela; Ntoimo, Lorreta; Adedini, Sunday

    2017-07-01

    Studies in South Africa have reported unsafe levels of risky sexual behvaiours among adolescents and young adults, with the country reporting the highest burden of HIV/AIDS globally, as well as a high rate of teenage pregnancy. While determinants of risky sexual behaviours have been investigated for factors occurring at the individual and household levels, not fully explored in the literature is the effect of community level factors. Furthermore, it is unclear whether risk factors occurring within the ecology of adolescents and young adults act cumulatively to influence their sexual practices. This article aims to address this knowledge gap using a case study of the Cape Area Panel Study of adolescents and young adults in urban Cape Town, South Africa. The ecological framework was adopted to guide the selection of risk factors at the individual, household, and community levels. Multivariate linear discriminant function analyses were used to select significant risk factors for multiple sexual partnerships and used to produce risk indices for the respondents. The cumulative risk approach was applied to test whether significant risk factors acted cumulatively. Findings point to the importance of ecological factors in influencing outcomes of multiple sexual partnerships among respondents and further demonstrate that ecological risk factors may act cumulatively. These findings are important for South Africa that is grappling with teenage pregnancy and disproportionate HIV epidemic among the youth.

  11. Avalanche multiplication and impact ionization in amorphous selenium photoconductive target

    NASA Astrophysics Data System (ADS)

    Park, Wug-Dong; Tanioka, Kenkichi

    2014-03-01

    The avalanche multiplication factor and the hole ionization coefficient in the amorphous selenium (a-Se) high-gain avalanche rushing amorphous photoconductor (HARP) target depend on the electric field. The phenomenon of avalanche multiplication and impact ionization in the 0.4-µm-thick a-Se HARP target is investigated. The hot carrier energy in the 0.4-µm-thick a-Se HARP target increases linearly as the target voltage increases. The energy relaxation length of hot carriers in the a-Se photoconductor of the 0.4-µm-thick HARP target saturates as the electric field increases. The average energy Eav of a hot carrier and the energy relaxation length λE in the a-Se photoconductor of the 0.4-µm-thick HARP target at 1 × 108 V/m were 0.25 eV and 2.5 nm, respectively. In addition, the hole ionization coefficient β and the avalanche multiplication factor M are derived as a function of the electric field, the average energy of a hot carrier, and the impact ionization energy. The experimental hole ionization coefficient β and the avalanche multiplication factor M in the 0.4-µm-thick a-Se HARP target agree with the theoretical results.

  12. Measurement of D-meson production versus multiplicity in p-Pb collisions at √{{s}_{NN}}=5.02 TeV

    NASA Astrophysics Data System (ADS)

    Adam, J.; Adamová, D.; Aggarwal, M. M.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahn, S. U.; Aiola, S.; Akindinov, A.; Alam, S. N.; Aleksandrov, D.; Alessandro, B.; Alexandre, D.; Alfaro Molina, R.; Alici, A.; Alkin, A.; Almaraz, J. R. M.; Alme, J.; Alt, T.; Altinpinar, S.; Altsybeev, I.; Alves Garcia Prado, C.; Andrei, C.; Andronic, A.; Anguelov, V.; Anielski, J.; Antičić, T.; Antinori, F.; Antonioli, P.; Aphecetche, L.; Appelshäuser, H.; Arcelli, S.; Arnaldi, R.; Arnold, O. W.; Arsene, I. C.; Arslandok, M.; Audurier, B.; Augustinus, A.; Averbeck, R.; Azmi, M. D.; Badalà, A.; Baek, Y. W.; Bagnasco, S.; Bailhache, R.; Bala, R.; Balasubramanian, S.; Baldisseri, A.; Baral, R. C.; Barbano, A. M.; Barbera, R.; Barile, F.; Barnaföldi, G. G.; Barnby, L. S.; Barret, V.; Bartalini, P.; Barth, K.; Bartke, J.; Bartsch, E.; Basile, M.; Bastid, N.; Basu, S.; Bathen, B.; Batigne, G.; Batista Camejo, A.; Batyunya, B.; Batzing, P. C.; Bearden, I. G.; Beck, H.; Bedda, C.; Behera, N. K.; Belikov, I.; Bellini, F.; Bello Martinez, H.; Bellwied, R.; Belmont, R.; Belmont-Moreno, E.; Belyaev, V.; Benacek, P.; Bencedi, G.; Beole, S.; Berceanu, I.; Bercuci, A.; Berdnikov, Y.; Berenyi, D.; Bertens, R. A.; Berzano, D.; Betev, L.; Bhasin, A.; Bhat, I. R.; Bhati, A. K.; Bhattacharjee, B.; Bhom, J.; Bianchi, L.; Bianchi, N.; Bianchin, C.; Bielčík, J.; Bielčíková, J.; Bilandzic, A.; Biro, G.; Biswas, R.; Biswas, S.; Bjelogrlic, S.; Blair, J. T.; Blau, D.; Blume, C.; Bock, F.; Bogdanov, A.; Bøggild, H.; Boldizsár, L.; Bombara, M.; Book, J.; Borel, H.; Borissov, A.; Borri, M.; Bossú, F.; Botta, E.; Bourjau, C.; Braun-Munzinger, P.; Bregant, M.; Breitner, T.; Broker, T. A.; Browning, T. A.; Broz, M.; Brucken, E. J.; Bruna, E.; Bruno, G. E.; Budnikov, D.; Buesching, H.; Bufalino, S.; Buncic, P.; Busch, O.; Buthelezi, Z.; Butt, J. B.; Buxton, J. T.; Caffarri, D.; Cai, X.; Caines, H.; Calero Diaz, L.; Caliva, A.; Calvo Villar, E.; Camerini, P.; Carena, F.; Carena, W.; Carnesecchi, F.; Castillo Castellanos, J.; Castro, A. J.; Casula, E. A. R.; Ceballos Sanchez, C.; Cerello, P.; Cerkala, J.; Chang, B.; Chapeland, S.; Chartier, M.; Charvet, J. L.; Chattopadhyay, S.; Chattopadhyay, S.; Chauvin, A.; Chelnokov, V.; Cherney, M.; Cheshkov, C.; Cheynis, B.; Chibante Barroso, V.; Chinellato, D. D.; Cho, S.; Chochula, P.; Choi, K.; Chojnacki, M.; Choudhury, S.; Christakoglou, P.; Christensen, C. H.; Christiansen, P.; Chujo, T.; Chung, S. U.; Cicalo, C.; Cifarelli, L.; Cindolo, F.; Cleymans, J.; Colamaria, F.; Colella, D.; Collu, A.; Colocci, M.; Conesa Balbastre, G.; Conesa del Valle, Z.; Connors, M. E.; Contreras, J. G.; Cormier, T. M.; Corrales Morales, Y.; Cortés Maldonado, I.; Cortese, P.; Cosentino, M. R.; Costa, F.; Crochet, P.; Cruz Albino, R.; Cuautle, E.; Cunqueiro, L.; Dahms, T.; Dainese, A.; Danu, A.; Das, D.; Das, I.; Das, S.; Dash, A.; Dash, S.; De, S.; De Caro, A.; de Cataldo, G.; de Conti, C.; de Cuveland, J.; De Falco, A.; De Gruttola, D.; De Marco, N.; De Pasquale, S.; Deisting, A.; Deloff, A.; Dénes, E.; Deplano, C.; Dhankher, P.; Di Bari, D.; Di Mauro, A.; Di Nezza, P.; Diaz Corchero, M. A.; Dietel, T.; Dillenseger, P.; Divià, R.; Djuvsland, Ø.; Dobrin, A.; Domenicis Gimenez, D.; Dönigus, B.; Dordic, O.; Drozhzhova, T.; Dubey, A. K.; Dubla, A.; Ducroux, L.; Dupieux, P.; Ehlers, R. J.; Elia, D.; Endress, E.; Engel, H.; Epple, E.; Erazmus, B.; Erdemir, I.; Erhardt, F.; Espagnon, B.; Estienne, M.; Esumi, S.; Eum, J.; Evans, D.; Evdokimov, S.; Eyyubova, G.; Fabbietti, L.; Fabris, D.; Faivre, J.; Fantoni, A.; Fasel, M.; Feldkamp, L.; Feliciello, A.; Feofilov, G.; Ferencei, J.; Fernández Téllez, A.; Ferreiro, E. G.; Ferretti, A.; Festanti, A.; Feuillard, V. J. G.; Figiel, J.; Figueredo, M. A. S.; Filchagin, S.; Finogeev, D.; Fionda, F. M.; Fiore, E. M.; Fleck, M. G.; Floris, M.; Foertsch, S.; Foka, P.; Fokin, S.; Fragiacomo, E.; Francescon, A.; Frankenfeld, U.; Fronze, G. G.; Fuchs, U.; Furget, C.; Furs, A.; Fusco Girard, M.; Gaardhøje, J. J.; Gagliardi, M.; Gago, A. M.; Gallio, M.; Gangadharan, D. R.; Ganoti, P.; Gao, C.; Garabatos, C.; Garcia-Solis, E.; Gargiulo, C.; Gasik, P.; Gauger, E. F.; Germain, M.; Gheata, A.; Gheata, M.; Ghosh, P.; Ghosh, S. K.; Gianotti, P.; Giubellino, P.; Giubilato, P.; Gladysz-Dziadus, E.; Glässel, P.; Goméz Coral, D. M.; Gomez Ramirez, A.; Gonzalez, V.; González-Zamora, P.; Gorbunov, S.; Görlich, L.; Gotovac, S.; Grabski, V.; Grachov, O. A.; Graczykowski, L. K.; Graham, K. L.; Grelli, A.; Grigoras, A.; Grigoras, C.; Grigoriev, V.; Grigoryan, A.; Grigoryan, S.; Grinyov, B.; Grion, N.; Gronefeld, J. M.; Grosse-Oetringhaus, J. F.; Grossiord, J.-Y.; Grosso, R.; Guber, F.; Guernane, R.; Guerzoni, B.; Gulbrandsen, K.; Gunji, T.; Gupta, A.; Gupta, R.; Haake, R.; Haaland, Ø.; Hadjidakis, C.; Haiduc, M.; Hamagaki, H.; Hamar, G.; Hamon, J. C.; Harris, J. W.; Harton, A.; Hatzifotiadou, D.; Hayashi, S.; Heckel, S. T.; Helstrup, H.; Herghelegiu, A.; Herrera Corral, G.; Hess, B. A.; Hetland, K. F.; Hillemanns, H.; Hippolyte, B.; Horak, D.; Hosokawa, R.; Hristov, P.; Huang, M.; Humanic, T. J.; Hussain, N.; Hussain, T.; Hutter, D.; Hwang, D. S.; Ilkaev, R.; Inaba, M.; Incani, E.; Ippolitov, M.; Irfan, M.; Ivanov, M.; Ivanov, V.; Izucheev, V.; Jacazio, N.; Jacobs, P. M.; Jadhav, M. B.; Jadlovska, S.; Jadlovsky, J.; Jahnke, C.; Jakubowska, M. J.; Jang, H. J.; Janik, M. A.; Jayarathna, P. H. S. Y.; Jena, C.; Jena, S.; Jimenez Bustamante, R. T.; Jones, P. G.; Jung, H.; Jusko, A.; Kalinak, P.; Kalweit, A.; Kamin, J.; Kang, J. H.; Kaplin, V.; Kar, S.; Karasu Uysal, A.; Karavichev, O.; Karavicheva, T.; Karayan, L.; Karpechev, E.; Kebschull, U.; Keidel, R.; Keijdener, D. L. D.; Keil, M.; Mohisin Khan, M.; Khan, P.; Khan, S. A.; Khanzadeev, A.; Kharlov, Y.; Kileng, B.; Kim, D. W.; Kim, D. J.; Kim, D.; Kim, H.; Kim, J. S.; Kim, M.; Kim, M.; Kim, S.; Kim, T.; Kirsch, S.; Kisel, I.; Kiselev, S.; Kisiel, A.; Kiss, G.; Klay, J. L.; Klein, C.; Klein, J.; Klein-Bösing, C.; Klewin, S.; Kluge, A.; Knichel, M. L.; Knospe, A. G.; Kobdaj, C.; Kofarago, M.; Kollegger, T.; Kolojvari, A.; Kondratiev, V.; Kondratyeva, N.; Kondratyuk, E.; Konevskikh, A.; Kopcik, M.; Kour, M.; Kouzinopoulos, C.; Kovalenko, O.; Kovalenko, V.; Kowalski, M.; Koyithatta Meethaleveedu, G.; Králik, I.; Kravčáková, A.; Kretz, M.; Krivda, M.; Krizek, F.; Kryshen, E.; Krzewicki, M.; Kubera, A. M.; Kučera, V.; Kuhn, C.; Kuijer, P. G.; Kumar, A.; Kumar, J.; Kumar, L.; Kumar, S.; Kurashvili, P.; Kurepin, A.; Kurepin, A. B.; Kuryakin, A.; Kweon, M. J.; Kwon, Y.; La Pointe, S. L.; La Rocca, P.; Ladron de Guevara, P.; Lagana Fernandes, C.; Lakomov, I.; Langoy, R.; Lara, C.; Lardeux, A.; Lattuca, A.; Laudi, E.; Lea, R.; Leardini, L.; Lee, G. R.; Lee, S.; Lehas, F.; Lemmon, R. C.; Lenti, V.; Leogrande, E.; León Monzón, I.; León Vargas, H.; Leoncino, M.; Lévai, P.; Li, S.; Li, X.; Lien, J.; Lietava, R.; Lindal, S.; Lindenstruth, V.; Lippmann, C.; Lisa, M. A.; Ljunggren, H. M.; Lodato, D. F.; Loenne, P. I.; Loginov, V.; Loizides, C.; Lopez, X.; López Torres, E.; Lowe, A.; Luettig, P.; Lunardon, M.; Luparello, G.; Lutz, T. H.; Maevskaya, A.; Mager, M.; Mahajan, S.; Mahmood, S. M.; Maire, A.; Majka, R. D.; Malaev, M.; Maldonado Cervantes, I.; Malinina, L.; Mal'Kevich, D.; Malzacher, P.; Mamonov, A.; Manko, V.; Manso, F.; Manzari, V.; Marchisone, M.; Mareš, J.; Margagliotti, G. V.; Margotti, A.; Margutti, J.; Marín, A.; Markert, C.; Marquard, M.; Martin, N. A.; Martin Blanco, J.; Martinengo, P.; Martínez, M. I.; Martínez García, G.; Martinez Pedreira, M.; Mas, A.; Masciocchi, S.; Masera, M.; Masoni, A.; Massacrier, L.; Mastroserio, A.; Matyja, A.; Mayer, C.; Mazer, J.; Mazzoni, M. A.; Mcdonald, D.; Meddi, F.; Melikyan, Y.; Menchaca-Rocha, A.; Meninno, E.; Mercado Pérez, J.; Meres, M.; Miake, Y.; Mieskolainen, M. M.; Mikhaylov, K.; Milano, L.; Milosevic, J.; Minervini, L. M.; Mischke, A.; Mishra, A. N.; Miskowiec, D.; Mitra, J.; Mitu, C. M.; Mohammadi, N.; Mohanty, B.; Molnar, L.; Montaño Zetina, L.; Montes, E.; Moreira De Godoy, D. A.; Moreno, L. A. P.; Moretto, S.; Morreale, A.; Morsch, A.; Muccifora, V.; Mudnic, E.; Mühlheim, D.; Muhuri, S.; Mukherjee, M.; Mulligan, J. D.; Munhoz, M. G.; Munzer, R. H.; Murakami, H.; Murray, S.; Musa, L.; Musinsky, J.; Naik, B.; Nair, R.; Nandi, B. K.; Nania, R.; Nappi, E.; Naru, M. U.; Natal da Luz, H.; Nattrass, C.; Navarro, S. R.; Nayak, K.; Nayak, R.; Nayak, T. K.; Nazarenko, S.; Nedosekin, A.; Nellen, L.; Ng, F.; Nicassio, M.; Niculescu, M.; Niedziela, J.; Nielsen, B. S.; Nikolaev, S.; Nikulin, S.; Nikulin, V.; Noferini, F.; Nomokonov, P.; Nooren, G.; Noris, J. C. C.; Norman, J.; Nyanin, A.; Nystrand, J.; Oeschler, H.; Oh, S.; Oh, S. K.; Ohlson, A.; Okatan, A.; Okubo, T.; Olah, L.; Oleniacz, J.; Oliveira Da Silva, A. C.; Oliver, M. H.; Onderwaater, J.; Oppedisano, C.; Orava, R.; Ortiz Velasquez, A.; Oskarsson, A.; Otwinowski, J.; Oyama, K.; Ozdemir, M.; Pachmayer, Y.; Pagano, P.; Paić, G.; Pal, S. K.; Pan, J.; Pandey, A. K.; Papcun, P.; Papikyan, V.; Pappalardo, G. S.; Pareek, P.; Park, W. J.; Parmar, S.; Passfeld, A.; Paticchio, V.; Patra, R. N.; Paul, B.; Pei, H.; Peitzmann, T.; Pereira Da Costa, H.; Peresunko, D.; Pérez Lara, C. E.; Perez Lezama, E.; Peskov, V.; Pestov, Y.; Petráček, V.; Petrov, V.; Petrovici, M.; Petta, C.; Piano, S.; Pikna, M.; Pillot, P.; Pimentel, L. O. D. L.; Pinazza, O.; Pinsky, L.; Piyarathna, D. B.; Ploskon, M.; Planinic, M.; Pluta, J.; Pochybova, S.; Podesta-Lerma, P. L. M.; Poghosyan, M. G.; Polichtchouk, B.; Poljak, N.; Poonsawat, W.; Pop, A.; Porteboeuf-Houssais, S.; Porter, J.; Pospisil, J.; Prasad, S. K.; Preghenella, R.; Prino, F.; Pruneau, C. A.; Pshenichnov, I.; Puccio, M.; Puddu, G.; Pujahari, P.; Punin, V.; Putschke, J.; Qvigstad, H.; Rachevski, A.; Raha, S.; Rajput, S.; Rak, J.; Rakotozafindrabe, A.; Ramello, L.; Rami, F.; Raniwala, R.; Raniwala, S.; Räsänen, S. S.; Rascanu, B. T.; Rathee, D.; Read, K. F.; Redlich, K.; Reed, R. J.; Rehman, A.; Reichelt, P.; Reidt, F.; Ren, X.; Renfordt, R.; Reolon, A. R.; Reshetin, A.; Revol, J.-P.; Reygers, K.; Riabov, V.; Ricci, R. A.; Richert, T.; Richter, M.; Riedler, P.; Riegler, W.; Riggi, F.; Ristea, C.; Rocco, E.; Rodríguez Cahuantzi, M.; Rodriguez Manso, A.; Røed, K.; Rogochaya, E.; Rohr, D.; Röhrich, D.; Romita, R.; Ronchetti, F.; Ronflette, L.; Rosnet, P.; Rossi, A.; Roukoutakis, F.; Roy, A.; Roy, C.; Roy, P.; Rubio Montero, A. J.; Rui, R.; Russo, R.; Ryabinkin, E.; Ryabov, Y.; Rybicki, A.; Sadovsky, S.; Šafařík, K.; Sahlmuller, B.; Sahoo, P.; Sahoo, R.; Sahoo, S.; Sahu, P. K.; Saini, J.; Sakai, S.; Saleh, M. A.; Salzwedel, J.; Sambyal, S.; Samsonov, V.; Šándor, L.; Sandoval, A.; Sano, M.; Sarkar, D.; Sarma, P.; Scapparone, E.; Scarlassara, F.; Schiaua, C.; Schicker, R.; Schmidt, C.; Schmidt, H. R.; Schuchmann, S.; Schukraft, J.; Schulc, M.; Schuster, T.; Schutz, Y.; Schwarz, K.; Schweda, K.; Scioli, G.; Scomparin, E.; Scott, R.; Šefčík, M.; Seger, J. E.; Sekiguchi, Y.; Sekihata, D.; Selyuzhenkov, I.; Senosi, K.; Senyukov, S.; Serradilla, E.; Sevcenco, A.; Shabanov, A.; Shabetai, A.; Shadura, O.; Shahoyan, R.; Shangaraev, A.; Sharma, A.; Sharma, M.; Sharma, M.; Sharma, N.; Shigaki, K.; Shtejer, K.; Sibiriak, Y.; Siddhanta, S.; Sielewicz, K. M.; Siemiarczuk, T.; Silvermyr, D.; Silvestre, C.; Simatovic, G.; Simonetti, G.; Singaraju, R.; Singh, R.; Singha, S.; Singhal, V.; Sinha, B. C.; Sinha, T.; Sitar, B.; Sitta, M.; Skaali, T. B.; Slupecki, M.; Smirnov, N.; Snellings, R. J. M.; Snellman, T. W.; Søgaard, C.; Song, J.; Song, M.; Song, Z.; Soramel, F.; Sorensen, S.; de Souza, R. D.; Sozzi, F.; Spacek, M.; Spiriti, E.; Sputowska, I.; Spyropoulou-Stassinaki, M.; Stachel, J.; Stan, I.; Stankus, P.; Stefanek, G.; Stenlund, E.; Steyn, G.; Stiller, J. H.; Stocco, D.; Strmen, P.; Suaide, A. A. P.; Sugitate, T.; Suire, C.; Suleymanov, M.; Suljic, M.; Sultanov, R.; Šumbera, M.; Szabo, A.; Szanto de Toledo, A.; Szarka, I.; Szczepankiewicz, A.; Szymanski, M.; Tabassam, U.; Takahashi, J.; Tambave, G. J.; Tanaka, N.; Tangaro, M. A.; Tarhini, M.; Tariq, M.; Tarzila, M. G.; Tauro, A.; Tejeda Muñoz, G.; Telesca, A.; Terasaki, K.; Terrevoli, C.; Teyssier, B.; Thäder, J.; Thomas, D.; Tieulent, R.; Timmins, A. R.; Toia, A.; Trogolo, S.; Trombetta, G.; Trubnikov, V.; Trzaska, W. H.; Tsuji, T.; Tumkin, A.; Turrisi, R.; Tveter, T. S.; Ullaland, K.; Uras, A.; Usai, G. L.; Utrobicic, A.; Vajzer, M.; Vala, M.; Valencia Palomo, L.; Vallero, S.; Van Der Maarel, J.; Van Hoorne, J. W.; van Leeuwen, M.; Vanat, T.; Vande Vyvre, P.; Varga, D.; Vargas, A.; Vargyas, M.; Varma, R.; Vasileiou, M.; Vasiliev, A.; Vauthier, A.; Vechernin, V.; Veen, A. M.; Veldhoen, M.; Velure, A.; Venaruzzo, M.; Vercellin, E.; Vergara Limón, S.; Vernet, R.; Verweij, M.; Vickovic, L.; Viesti, G.; Viinikainen, J.; Vilakazi, Z.; Villalobos Baillie, O.; Villatoro Tello, A.; Vinogradov, A.; Vinogradov, L.; Vinogradov, Y.; Virgili, T.; Vislavicius, V.; Viyogi, Y. P.; Vodopyanov, A.; Völkl, M. A.; Voloshin, K.; Voloshin, S. A.; Volpe, G.; von Haller, B.; Vorobyev, I.; Vranic, D.; Vrláková, J.; Vulpescu, B.; Wagner, B.; Wagner, J.; Wang, H.; Wang, M.; Watanabe, D.; Watanabe, Y.; Weber, M.; Weber, S. G.; Weiser, D. F.; Wessels, J. P.; Westerhoff, U.; Whitehead, A. M.; Wiechula, J.; Wikne, J.; Wilde, M.; Wilk, G.; Wilkinson, J.; Williams, M. C. S.; Windelband, B.; Winn, M.; Yaldo, C. G.; Yang, H.; Yang, P.; Yano, S.; Yasar, C.; Yin, Z.; Yokoyama, H.; Yoo, I.-K.; Yoon, J. H.; Yurchenko, V.; Yushmanov, I.; Zaborowska, A.; Zaccolo, V.; Zaman, A.; Zampolli, C.; Zanoli, H. J. C.; Zaporozhets, S.; Zardoshti, N.; Zarochentsev, A.; Závada, P.; Zaviyalov, N.; Zbroszczyk, H.; Zgura, I. S.; Zhalov, M.; Zhang, H.; Zhang, X.; Zhang, Y.; Zhang, C.; Zhang, Z.; Zhao, C.; Zhigareva, N.; Zhou, D.; Zhou, Y.; Zhou, Z.; Zhu, H.; Zhu, J.; Zichichi, A.; Zimmermann, A.; Zimmermann, M. B.; Zinovjev, G.; Zyzak, M.

    2016-08-01

    The measurement of prompt D-meson production as a function of multiplicity in p-Pb collisions at √{s_{NN}}=5.02 TeV with the ALICE detector at the LHC is reported. D0, D+ and D∗+ mesons are reconstructed via their hadronic decay channels in the centre-of-mass rapidity range -0 .96 < y cms < 0 .04 and transverse momentum interval 1

  13. The influence of the interactions between anthropogenic activities and multiple ecological factors on land surface temperatures of urban forests

    NASA Astrophysics Data System (ADS)

    Ren, Y.

    2017-12-01

    Context Land surface temperatures (LSTs) spatio-temporal distribution pattern of urban forests are influenced by many ecological factors; the identification of interaction between these factors can improve simulations and predictions of spatial patterns of urban cold islands. This quantitative research requires an integrated method that combines multiple sources data with spatial statistical analysis. Objectives The purpose of this study was to clarify urban forest LST influence interaction between anthropogenic activities and multiple ecological factors using cluster analysis of hot and cold spots and Geogdetector model. We introduced the hypothesis that anthropogenic activity interacts with certain ecological factors, and their combination influences urban forests LST. We also assumed that spatio-temporal distributions of urban forest LST should be similar to those of ecological factors and can be represented quantitatively. Methods We used Jinjiang as a representative city in China as a case study. Population density was employed to represent anthropogenic activity. We built up a multi-source data (forest inventory, digital elevation models (DEM), population, and remote sensing imagery) on a unified urban scale to support urban forest LST influence interaction research. Through a combination of spatial statistical analysis results, multi-source spatial data, and Geogdetector model, the interaction mechanisms of urban forest LST were revealed. Results Although different ecological factors have different influences on forest LST, in two periods with different hot spots and cold spots, the patch area and dominant tree species were the main factors contributing to LST clustering in urban forests. The interaction between anthropogenic activity and multiple ecological factors increased LST in urban forest stands, linearly and nonlinearly. Strong interactions between elevation and dominant species were generally observed and were prevalent in either hot or cold spots areas in different years. Conclusions In conclusion, a combination of spatial statistics and GeogDetector models should be effective for quantitatively evaluating interactive relationships among ecological factors, anthropogenic activity and LST.

  14. Cool's Clams Casino

    ERIC Educational Resources Information Center

    Cobey, Paul; Williams, David E.

    1977-01-01

    A mathematical game that reinforces basic multiplication facts, strengthens concepts of factors and multiples, and also provides arithmetic drill is described. Four variations of the game are also provided. (JT)

  15. Development of the Perceived Multiple Role Stress Scale (PMRS).

    PubMed

    Gigliotti, E

    2001-01-01

    Assessment of women's perception of multiple-role stress arising from occupancy of the maternal and student role is crucial if we are to engage in prevention and intervention strategies. Existing measures do not fully address the components of multiple role stress in this population: emotional role ambiguity, person-role and inter-role conflict. This article describes the development of the Perceived Multiple Role Stress Scale (PMRS) which was derived from Kahn, Wolfe, Quinn and Snoek's (1964) systems-based role theory. The 8-item, 3-factor PMRS measures multiple role stress in women who are both mothers and students. Review of the PMRS by role stress and women's roles experts supported content validity. Construct validity was supported in three phases over a five-year period. It is recommended that the three correlated factors be used as one eight-item scale. The internal consistency for the PMRS was .86.

  16. Behavioral and psychosocial factors associated with suicidal ideation among adolescents.

    PubMed

    Lee, GyuYoung; Ham, Ok Kyung

    2018-04-10

    Suicidal ideation poses a serious threat to the well-being of adolescents and is the strongest risk factor for suicide. Indeed, Korea ranks first among Organisation for Economic Cooperation and Development countries regarding the age-standardized suicide rates. In the present study, we examined multiple levels of factors associated with the suicidal ideation of adolescents in Korea by applying the Ecological Models of Health Behavior. A cross-sectional study was conducted with a convenience sample of 860 adolescents. The instruments included the Beck Depression Inventory and the Adolescent Mental Health and Problem Behavior Questionnaire. The data were analyzed using hierarchical multiple regression. Sixteen percent of participants reported suicidal ideation. Intrapersonal (sleep disturbance, Internet game addiction, destructive behavior, and depressive symptoms) and interpersonal factors (family conflicts and peer victimization) were associated with suicidal ideation. Because multiple factors were associated with suicidal ideation among adolescents, both intrapersonal (sleep disturbance, Internet game addiction, and depression) and interpersonal factors (family conflicts and peer problems) should be considered in the development of suicide-prevention programs. These programs could include campaigns changing the norms (permissive attitudes toward school violence) and the development of strict and rigorous school non-violence policies. © 2018 John Wiley & Sons Australia, Ltd.

  17. Recovering hidden diagonal structures via non-negative matrix factorization with multiple constraints.

    PubMed

    Yang, Xi; Han, Guoqiang; Cai, Hongmin; Song, Yan

    2017-03-31

    Revealing data with intrinsically diagonal block structures is particularly useful for analyzing groups of highly correlated variables. Earlier researches based on non-negative matrix factorization (NMF) have been shown to be effective in representing such data by decomposing the observed data into two factors, where one factor is considered to be the feature and the other the expansion loading from a linear algebra perspective. If the data are sampled from multiple independent subspaces, the loading factor would possess a diagonal structure under an ideal matrix decomposition. However, the standard NMF method and its variants have not been reported to exploit this type of data via direct estimation. To address this issue, a non-negative matrix factorization with multiple constraints model is proposed in this paper. The constraints include an sparsity norm on the feature matrix and a total variational norm on each column of the loading matrix. The proposed model is shown to be capable of efficiently recovering diagonal block structures hidden in observed samples. An efficient numerical algorithm using the alternating direction method of multipliers model is proposed for optimizing the new model. Compared with several benchmark models, the proposed method performs robustly and effectively for simulated and real biological data.

  18. Factors predictive of alcohol abstention after resident detoxication among alcoholics followed in an hospital outpatient center.

    PubMed

    Gelsi, Eve; Vanbiervliet, Geoffroy; Chérikh, Faredj; Mariné-Barjoan, Eugénia; Truchi, Régine; Arab, Kamel; Delmont, Jean-Marie; Tran, Albert

    2007-01-01

    A cohort of patient hospitalized for alcohol detoxification between January 2004 and January 2005 were followed prospectively to search for factors predictive factors of sustained abstinence. One hundred and fifteen patients (79 males, 36 females, median age 45.9+/-10.7 years), were hospitalized for alcohol detoxification. Demographic, social, and medical data including daily alcohol intake and co-addictions were noted at inclusion and six months later. Patients who did not attend their six-month visit were contacted by phone. Among the 115 included patients, six month follow-up data could be collected for 73. Abstinence rate was 54.8%. Factors predictive of unsuccessful cessation were homelessness (P=0.004), duration of alcohol consumption (P=0.004), smoking (P=0.02), drug substitution (P=0.04) and multiple addictions (P=0.04). At multivariate analysis, multiple addictions was the only independent factor predictive of unsuccessful detoxification. Naltrexone or acamprosate treatments were not associated with a better rate of alcohol detoxification. Patient follow-up is problematic due to the large number of dropouts among alcoholics. Early screening in search for factors predictive of unsuccessful detoxification (long duration of alcohol consumption, multiple addiction) would be helpful in elaborating appropriate pluridisciplinary management.

  19. Prognostic factors in multiple myeloma: selection using Cox's proportional hazard model.

    PubMed

    Pasqualetti, P; Collacciani, A; Maccarone, C; Casale, R

    1996-01-01

    The pretreatment characteristics of 210 patients with multiple myeloma, observed between 1980 and 1994, were evaluated as potential prognostic factors for survival. Multivariate analysis according to Cox's proportional hazard model identified in the 160 dead patients with myeloma, among 26 different single prognostic variables, the following factors in order of importance: beta 2-microglobulin; bone marrow plasma cell percentage, hemoglobinemia, degree of lytic bone lesions, serum creatinine, and serum albumin. By analysis of these variables a prognostic index (PI), that considers the regression coefficients derived by Cox's model of all significant factors, was obtained. Using this it was possible to separate the whole patient group into three stages: stage I (PI < 1.485, 67 patients), stage II (PI: 1.485-2.090, 76 patients), and stage III (PI > 2.090, 67 patients), with a median survivals of 68, 36 and 13 months (P < 0.0001), respectively. Also the responses to therapy (P < 0.0001) and the survival curves (P < 0.00001) presented significant differences among the three subgroups. Knowledge of these factors could be of value in predicting prognosis and in planning therapy in patients with multiple myeloma.

  20. Multiple Factors-Aware Diffusion in Social Networks

    DTIC Science & Technology

    2015-05-22

    Multiple Factors-Aware Diffusion in Social Networks Chung-Kuang Chou(B) and Ming-Syan Chen Department of Electrical Engineering, National Taiwan...propagates from nodes to nodes over a social network . The behavior that a node adopts an information piece in a social network can be affected by...Twitter dataset. Keywords: Social networks · Diffusion models 1 Introduction Information diffusion in social networks has been an active research field

  1. Complications in multiple gestation pregnancy: A cross-sectional study of ten maternal-fetal medicine centers in China

    PubMed Central

    Wei, Jun; Wu, Qi-Jun; Zhang, Tie-Ning; Shen, Zi-Qi; Liu, Hao; Zheng, Dong-Ming; Cui, Hong; Liu, Cai-Xia

    2016-01-01

    Complications in women with multiple gestation pregnancy have not been studied in China. We aimed to establish a database of women with multiple gestation pregnancy and investigate the complications related to multiple pregnancy. We conducted a cross-sectional study that included 3246 women with multiple gestation pregnancy and who had multiple live-birth deliveries; the women were registered at ten maternal-fetal medicine centers in China in 2013. All participants completed a detailed questionnaire that included basic demographic information, history of gestation and abnormal fetal development, risk factors during pregnancy, and pregnancy outcomes. Overall, 1553 (47.8%) women experienced pregnancy complications; these women were more likely to have lower height and less education than women who did not experience complications. However, women who experienced complications had a higher twin birth rate and were more likely to have received regular antenatal care and assisted reproductive technology than women without complications (P < 0.05). Notably, preterm birth was a primary complication in multiple pregnancy (n = 960). In conclusion, pregnancy complications, especially preterm birth, were relatively common in women with multiple gestation pregnancy. The findings from this cross-sectional study in China may be used as a foundation for investigating risk factors for complications in women with multiple gestation pregnancy in the future. PMID:27127170

  2. Complications in multiple gestation pregnancy: A cross-sectional study of ten maternal-fetal medicine centers in China.

    PubMed

    Wei, Jun; Wu, Qi-Jun; Zhang, Tie-Ning; Shen, Zi-Qi; Liu, Hao; Zheng, Dong-Ming; Cui, Hong; Liu, Cai-Xia

    2016-05-24

    Complications in women with multiple gestation pregnancy have not been studied in China. We aimed to establish a database of women with multiple gestation pregnancy and investigate the complications related to multiple pregnancy. We conducted a cross-sectional study that included 3246 women with multiple gestation pregnancy and who had multiple live-birth deliveries; the women were registered at ten maternal-fetal medicine centers in China in 2013. All participants completed a detailed questionnaire that included basic demographic information, history of gestation and abnormal fetal development, risk factors during pregnancy, and pregnancy outcomes. Overall, 1553 (47.8%) women experienced pregnancy complications; these women were more likely to have lower height and less education than women who did not experience complications. However, women who experienced complications had a higher twin birth rate and were more likely to have received regular antenatal care and assisted reproductive technology than women without complications (P < 0.05). Notably, preterm birth was a primary complication in multiple pregnancy (n = 960). In conclusion, pregnancy complications, especially preterm birth, were relatively common in women with multiple gestation pregnancy. The findings from this cross-sectional study in China may be used as a foundation for investigating risk factors for complications in women with multiple gestation pregnancy in the future.

  3. Growth factor transgenes interactively regulate articular chondrocytes.

    PubMed

    Shi, Shuiliang; Mercer, Scott; Eckert, George J; Trippel, Stephen B

    2013-04-01

    Adult articular chondrocytes lack an effective repair response to correct damage from injury or osteoarthritis. Polypeptide growth factors that stimulate articular chondrocyte proliferation and cartilage matrix synthesis may augment this response. Gene transfer is a promising approach to delivering such factors. Multiple growth factor genes regulate these cell functions, but multiple growth factor gene transfer remains unexplored. We tested the hypothesis that multiple growth factor gene transfer selectively modulates articular chondrocyte proliferation and matrix synthesis. We tested the hypothesis by delivering combinations of the transgenes encoding insulin-like growth factor I (IGF-I), fibroblast growth factor-2 (FGF-2), transforming growth factor beta1 (TGF-β1), bone morphogenetic protein-2 (BMP-2), and bone morphogenetic protien-7 (BMP-7) to articular chondrocytes and measured changes in the production of DNA, glycosaminoglycan, and collagen. The transgenes differentially regulated all these chondrocyte activities. In concert, the transgenes interacted to generate widely divergent responses from the cells. These interactions ranged from inhibitory to synergistic. The transgene pair encoding IGF-I and FGF-2 maximized cell proliferation. The three-transgene group encoding IGF-I, BMP-2, and BMP-7 maximized matrix production and also optimized the balance between cell proliferation and matrix production. These data demonstrate an approach to articular chondrocyte regulation that may be tailored to stimulate specific cell functions, and suggest that certain growth factor gene combinations have potential value for cell-based articular cartilage repair. Copyright © 2012 Wiley Periodicals, Inc.

  4. Single-Molecule Studies of Actin Assembly and Disassembly Factors

    PubMed Central

    Smith, Benjamin A.; Gelles, Jeff; Goode, Bruce L.

    2014-01-01

    The actin cytoskeleton is very dynamic and highly regulated by multiple associated proteins in vivo. Understanding how this system of proteins functions in the processes of actin network assembly and disassembly requires methods to dissect the mechanisms of activity of individual factors and of multiple factors acting in concert. The advent of single-filament and single-molecule fluorescence imaging methods has provided a powerful new approach to discovering actin-regulatory activities and obtaining direct, quantitative insights into the pathways of molecular interactions that regulate actin network architecture and dynamics. Here we describe techniques for acquisition and analysis of single-molecule data, applied to the novel challenges of studying the filament assembly and disassembly activities of actin-associated proteins in vitro. We discuss the advantages of single-molecule analysis in directly visualizing the order of molecular events, measuring the kinetic rates of filament binding and dissociation, and studying the coordination among multiple factors. The methods described here complement traditional biochemical approaches in elucidating actin-regulatory mechanisms in reconstituted filamentous networks. PMID:24630103

  5. XAFS Debye-Waller Factors Temperature-Dependent Expressions for Fe+2-Porphyrin Complexes

    NASA Astrophysics Data System (ADS)

    Dimakis, Nicholas; Bunker, Grant

    2007-02-01

    We present an efficient and accurate method for directly calculating single and multiple scattering X-ray absorption fine structure (XAFS) thermal Debye-Waller factors for Fe+2 -porphiryn complexes. The number of multiple scattering Debye-Waller factors on metal porphyrin centers exceeds the number of available parameters that XAFS experimental data can support during fitting with simulated spectra. Using the Density Functional Theory (DFT) under the hybrid functional of X3LYP, phonon normal mode spectrum properties are used to express the mean square variation of the half-scattering path length for a Fe+2 -porphiryn complex as a function of temperature for the most important single and multiple scattering paths of the complex thus virtually eliminating them from the fitting procedure. Modeled calculations are compared with corresponding values obtained from DFT-built and optimized Fe+2 -porphyrin bis-histidine structure as well as from experimental XAFS spectra previously reported. An excellent agreement between calculated and reference Debye-Waller factors for Fe+2-porphyrins is obtained.

  6. Predictors of transitions from single to multiple job holding: Results of a longitudinal study among employees aged 45-64 in the Netherlands.

    PubMed

    Bouwhuis, Stef; Geuskens, Goedele A; Boot, Cécile R L; Bongers, Paulien M; van der Beek, Allard J

    2017-08-01

    To construct prediction models for transitions to combination multiple job holding (MJH) (multiple jobs as an employee) and hybrid MJH (being an employee and self-employed), among employees aged 45-64. A total of 5187 employees in the Netherlands completed online questionnaires annually between 2010 and 2013. We applied logistic regression analyses with a backward elimination strategy to construct prediction models. Transitions to combination MJH and hybrid MJH were best predicted by a combination of factors including: demographics, health and mastery, work characteristics, work history, skills and knowledge, social factors, and financial factors. Not having a permanent contract and a poor household financial situation predicted both transitions. Some predictors only predicted combination MJH, e.g., working part-time, or hybrid MJH, e.g., work-home interference. A wide variety of factors predict combination MJH and/or hybrid MJH. The prediction model approach allowed for the identification of predictors that have not been previously studied. © 2017 Wiley Periodicals, Inc.

  7. Hepatectomy As A First Choice Treatment For Liver Metastasis From Gastric Cancer: A Single Center Experience.

    PubMed

    Sakamoto, Hirohiko; Amikura, Katsumi; Tanaka, Yoichi; Kawashima, Yoshiyuki

    2014-05-01

    Indication of hepatectomy for liver metastases from gastric cancer (LMGC) is still controversial despite many papers favoring surgery. The aim of this study is to claim that we should accept hepatectomy as first choice treatment for LMGC. It is important to have a consensus on this matter for surgeons to treat LMGC properly. Fifty three patients undergoing hepatectomy for LMGC from 1990 through 2010 were retrospectively analysed for survival and prognostic factors. Analyses were made on size, multiplicity, synchronicity and positive surgical margin as liver metastasis factors. Serosal invasion, node metastasis, histological differentiation and UICC stage were analysed as primary site factors. Multivariate analysis was performed for those positive for univariate analysis. Cumulative 5 year survival rate was 27%. Multiplicity, positive margin and node metastasis (N > 2) yielded significant difference on univariate analysis. On multivariate analysis multiplicity and node metastasis (N > 2) were significant. Hepatectomy for LMGC is potentially curative and should be regarded as first choice. Solitary and N < 3 are good prognostic factors.

  8. The NASA Ames PAH IR Spectroscopic Database: Computational Version 3.00 with Updated Content and the Introduction of Multiple Scaling Factors

    NASA Astrophysics Data System (ADS)

    Bauschlicher, Charles W., Jr.; Ricca, A.; Boersma, C.; Allamandola, L. J.

    2018-02-01

    Version 3.00 of the library of computed spectra in the NASA Ames PAH IR Spectroscopic Database (PAHdb) is described. Version 3.00 introduces the use of multiple scale factors, instead of the single scaling factor used previously, to align the theoretical harmonic frequencies with the experimental fundamentals. The use of multiple scale factors permits the use of a variety of basis sets; this allows new PAH species to be included in the database, such as those containing oxygen, and yields an improved treatment of strained species and those containing nitrogen. In addition, the computed spectra of 2439 new PAH species have been added. The impact of these changes on the analysis of an astronomical spectrum through database-fitting is considered and compared with a fit using Version 2.00 of the library of computed spectra. Finally, astronomical constraints are defined for the PAH spectral libraries in PAHdb.

  9. Evolution of multiple quantum coherences with scaled dipolar Hamiltonian

    NASA Astrophysics Data System (ADS)

    Sánchez, Claudia M.; Buljubasich, Lisandro; Pastawski, Horacio M.; Chattah, Ana K.

    2017-08-01

    In this article, we introduce a pulse sequence which allows the monitoring of multiple quantum coherences distribution of correlated spin states developed with scaled dipolar Hamiltonian. The pulse sequence is a modification of our previous Proportionally Refocused Loschmidt echo (PRL echo) with phase increment, in order to verify the accuracy of the weighted coherent quantum dynamics. The experiments were carried out with different scaling factors to analyze the evolution of the total magnetization, the time dependence of the multiple quantum coherence orders, and the development of correlated spins clusters. In all cases, a strong dependence between the evolution rate and the weighting factor is observed. Remarkably, all the curves appeared overlapped in a single trend when plotted against the self-time, a new time scale that includes the scaling factor into the evolution time. In other words, the spin system displayed always the same quantum evolution, slowed down as the scaling factor decreases, confirming the high performance of the new pulse sequence.

  10. Exploring the multiple-hit hypothesis of preterm white matter damage using diffusion MRI.

    PubMed

    Barnett, Madeleine L; Tusor, Nora; Ball, Gareth; Chew, Andrew; Falconer, Shona; Aljabar, Paul; Kimpton, Jessica A; Kennea, Nigel; Rutherford, Mary; David Edwards, A; Counsell, Serena J

    2018-01-01

    Preterm infants are at high risk of diffuse white matter injury and adverse neurodevelopmental outcome. The multiple hit hypothesis suggests that the risk of white matter injury increases with cumulative exposure to multiple perinatal risk factors. Our aim was to test this hypothesis in a large cohort of preterm infants using diffusion weighted magnetic resonance imaging (dMRI). We studied 491 infants (52% male) without focal destructive brain lesions born at < 34 weeks, who underwent structural and dMRI at a specialist Neonatal Imaging Centre. The median (range) gestational age (GA) at birth was 30 + 1 (23 + 2 -33 + 5 ) weeks and median postmenstrual age at scan was 42 + 1 (38-45) weeks. dMRI data were analyzed using tract based spatial statistics and the relationship between dMRI measures in white matter and individual perinatal risk factors was assessed. We tested the hypothesis that increased exposure to perinatal risk factors was associated with lower fractional anisotropy (FA), and higher radial, axial and mean diffusivity (RD, AD, MD) in white matter. Neurodevelopmental performance was investigated using the Bayley Scales of Infant and Toddler Development, Third Edition (BSITD-III) in a subset of 381 infants at 20 months corrected age. We tested the hypothesis that lower FA and higher RD, AD and MD in white matter were associated with poorer neurodevelopmental performance. Identified risk factors for diffuse white matter injury were lower GA at birth, fetal growth restriction, increased number of days requiring ventilation and parenteral nutrition, necrotizing enterocolitis and male sex. Clinical chorioamnionitis and patent ductus arteriosus were not associated with white matter injury. Multivariate analysis demonstrated that fetal growth restriction, increased number of days requiring ventilation and parenteral nutrition were independently associated with lower FA values. Exposure to cumulative risk factors was associated with reduced white matter FA and FA values at term equivalent age were associated with subsequent neurodevelopmental performance. This study suggests multiple perinatal risk factors have an independent association with diffuse white matter injury at term equivalent age and exposure to multiple perinatal risk factors exacerbates dMRI defined, clinically significant white matter injury. Our findings support the multiple hit hypothesis for preterm white matter injury.

  11. Retrospective Evaluation of Safety, Efficacy and Risk Factors for Pneumothorax in Simultaneous Localizations of Multiple Pulmonary Nodules Using Hook Wire System.

    PubMed

    Zhong, Yan; Xu, Xiao-Quan; Pan, Xiang-Long; Zhang, Wei; Xu, Hai; Yuan, Mei; Kong, Ling-Yan; Pu, Xue-Hui; Chen, Liang; Yu, Tong-Fu

    2017-09-01

    To evaluate the safety and efficacy of the hook wire system in the simultaneous localizations for multiple pulmonary nodules (PNs) before video-assisted thoracoscopic surgery (VATS), and to clarify the risk factors for pneumothorax associated with the localization procedure. Between January 2010 and February 2016, 67 patients (147 nodules, Group A) underwent simultaneous localizations for multiple PNs using a hook wire system. The demographic, localization procedure-related information and the occurrence rate of pneumothorax were assessed and compared with a control group (349 patients, 349 nodules, Group B). Multivariate logistic regression analyses were used to determine the risk factors for pneumothorax during the localization procedure. All the 147 nodules were successfully localized. Four (2.7%) hook wires dislodged before VATS procedure, but all these four lesions were successfully resected according to the insertion route of hook wire. Pathological diagnoses were acquired for all 147 nodules. Compared with Group B, Group A demonstrated significantly longer procedure time (p < 0.001) and higher occurrence rate of pneumothorax (p = 0.019). Multivariate logistic regression analysis indicated that position change during localization procedure (OR 2.675, p = 0.021) and the nodules located in the ipsilateral lung (OR 9.404, p < 0.001) were independent risk factors for pneumothorax. Simultaneous localizations for multiple PNs using a hook wire system before VATS procedure were safe and effective. Compared with localization for single PN, simultaneous localizations for multiple PNs were prone to the occurrence of pneumothorax. Position change during localization procedure and the nodules located in the ipsilateral lung were independent risk factors for pneumothorax.

  12. Risk factors for development of multiple-class resistance to Streptococcus pneumoniae Strains in Belgium over a 10-year period: antimicrobial consumption, population density, and geographic location.

    PubMed

    Van Eldere, Johan; Mera, Robertino M; Miller, Linda A; Poupard, James A; Amrine-Madsen, Heather

    2007-10-01

    We investigated the impact of the usage of antibiotics in ambulatory patients in Belgium in 147 defined geographical circumscriptions and at the individual isolate level. The study included 14,448 Streptococcus pneumoniae strains collected by the Belgium national reference lab from 1994 to 2004. Additional risk factors for resistance, such as population density/structure and day care attendance, were investigated for the same time-space window. A statistical model that included resistance to two or more antimicrobial classes offered the best fit for measuring the changes in nonsusceptibility to penicillin, macrolides, and tetracycline over time and place in Belgium. Analysis at the geographic level identified antimicrobial consumption with a 1-year lag (0.5% increase per additional defined daily dose) and population density as independent predictors of multiple resistance. Independent risk factors at the isolate level were age (odds ratio [OR], 1.55 for children aged <5 years), population density (7% increase in multiple resistance per 100 inhabitants/km(2)), conjugate 7-valent vaccine serotype (OR, 14.3), location (OR, 1.55 for regions bordering high-resistance France), and isolate source (OR, 1.54 for ear isolates). The expansion of multiple-resistant strains explains most of the overall twofold increase and subsequent decrease in single antimicrobial resistance between 1994 and 2004. We conclude that factors in addition to antibiotic use, such as high population density and proximity to high-resistance regions, favor multiple resistance. Regional resistance rates are not linearly related to actual antibiotic use but are linked to past antibiotic use plus a combination of demographic and geographic factors.

  13. Risk factors of suicide mortality among multiple attempters: A national registry study in Taiwan.

    PubMed

    Chen, I-Ming; Liao, Shih-Cheng; Lee, Ming-Been; Wu, Chia-Yi; Lin, Po-Hsien; Chen, Wei J

    2016-05-01

    Little is known about the risk factors of suicide mortality among multiple attempters. This study aims to investigate the predictors of suicidal mortality in a prospective cohort of attempters in Taiwan, focusing on the time interval and suicide method change between the last two nonfatal attempts. The representative data retrieved from the National Suicide Surveillance System (NSSS) was linked with National Mortality Database to identify the causes of death in multiple attempters during 2006-2008. Cox-proportional hazard models were applied to calculate the hazard ratios for the predictors of suicide. Among the 55,560 attempters, 6485 (11.7%) had survived attempts ranging from one to 11 times; 861 (1.5%) eventually died by suicide. Multiple attempters were characterized by female (OR = 1.56, p < 0.0001), nonrecipient of national aftercare service (OR = 1.62, p < 0.0001), and current contact with mental health services (OR = 3.17, p < 0.0001). Most multiple attempters who survived from hanging (68.1%) and gas poisoning (61.9%) chose the same method in the following fatal episode. Predictors of suicidal death were identified as male, older age (≥ 45 years), shorter interval and not maintaining methods of low lethality in the last two nonfatal attempts. Receipt of nationwide aftercare was associated with lower risk of suicide but the effect was insignificant. The time interval of the last two nonfatal attempts and alteration in the lethality of suicide method were significant factors for completed suicide. Risk assessment involving these two factors may be necessary for multiple attempters in different clinical settings. Effective strategies for suicide prevention emphasizing this high risk population should be developed in the future. Copyright © 2015. Published by Elsevier B.V.

  14. Analyzing and Integrating Models of Multiple Text Comprehension

    ERIC Educational Resources Information Center

    List, Alexandra; Alexander, Patricia A.

    2017-01-01

    We introduce a special issue featuring four theoretical models of multiple text comprehension. We present a central framework for conceptualizing the four models in this special issue. Specifically, we chart the models according to how they consider learner, texts, task, and context factors in explaining multiple text comprehension. In addition,…

  15. Multiple factors explain injury risk in adolescent elite athletes: Applying a biopsychosocial perspective.

    PubMed

    von Rosen, P; Frohm, A; Kottorp, A; Fridén, C; Heijne, A

    2017-12-01

    Many risk factors for injury are presented in the literature, few of those are however consistent and the majority is associated with adult and not adolescent elite athletes. The aim was to identify risk factors for injury in adolescent elite athletes, by applying a biopsychosocial approach. A total of 496 adolescent elite athletes (age range 15-19), participating in 16 different sports, were monitored repeatedly over 52 weeks using a valid questionnaire about injuries, training exposure, sleep, stress, nutrition, and competence-based self-esteem. Univariate and multiple Cox regression analyses were used to calculate hazard ratios (HR) for risk factors for first reported injury. The main finding was that an increase in training load, training intensity, and at the same time decreasing the sleep volume resulted in a higher risk for injury compared to no change in these variables (HR 2.25, 95% CI, 1.46-3.45, P<.01), which was the strongest risk factor identified. In addition, an increase by one score of competence-based self-esteem increased the hazard for injury with 1.02 (HR 95% CI, 1.00-1.04, P=.01). Based on the multiple Cox regression analysis, an athlete having the identified risk factors (Risk Index, competence-based self-esteem), with an average competence-based self-esteem score, had more than a threefold increased risk for injury (HR 3.35), compared to an athlete with a low competence-based self-esteem and no change in sleep or training volume. Our findings confirm injury occurrence as a result of multiple risk factors interacting in complex ways. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Influence of multiple scattering on CloudSat measurements in snow: A model study

    NASA Astrophysics Data System (ADS)

    Matrosov, Sergey Y.; Battaglia, Alessandro

    2009-06-01

    The effects of multiple scattering on larger precipitating hydrometers have an influence on measurements of the spaceborne W-band (94 GHz) CloudSat radar. This study presents initial quantitative estimates of these effects in “dry” snow using radiative transfer calculations for appropriate snowfall models. It is shown that these effects become significant (i.e., greater than approximately 1 dB) when snowfall radar reflectivity factors are greater than about 10-15 dBZ. Reflectivity enhancement due to multiple scattering can reach 4-5 dB in heavier stratiform snowfalls. Multiple scattering effects counteract signal attenuation, so the observed CloudSat reflectivity factors in snowfall could be relatively close to the values that would be observed in the case of single scattering and the absence of attenuation.

  17. Interactive effects of global change factors on soil respiration and its components: a meta-analysis.

    PubMed

    Zhou, Lingyan; Zhou, Xuhui; Shao, Junjiong; Nie, Yuanyuan; He, Yanghui; Jiang, Liling; Wu, Zhuoting; Hosseini Bai, Shahla

    2016-09-01

    As the second largest carbon (C) flux between the atmosphere and terrestrial ecosystems, soil respiration (Rs) plays vital roles in regulating atmospheric CO2 concentration ([CO2 ]) and climatic dynamics in the earth system. Although numerous manipulative studies and a few meta-analyses have been conducted to determine the responses of Rs and its two components [i.e., autotrophic (Ra) and heterotrophic (Rh) respiration] to single global change factors, the interactive effects of the multiple factors are still unclear. In this study, we performed a meta-analysis of 150 multiple-factor (≥2) studies to examine the main and interactive effects of global change factors on Rs and its two components. Our results showed that elevated [CO2 ] (E), nitrogen addition (N), irrigation (I), and warming (W) induced significant increases in Rs by 28.6%, 8.8%, 9.7%, and 7.1%, respectively. The combined effects of the multiple factors, EN, EW, DE, IE, IN, IW, IEW, and DEW, were also significantly positive on Rs to a greater extent than those of the single-factor ones. For all the individual studies, the additive interactions were predominant on Rs (90.6%) and its components (≈70.0%) relative to synergistic and antagonistic ones. However, the different combinations of global change factors (e.g., EN, NW, EW, IW) indicated that the three types of interactions were all important, with two combinations for synergistic effects, two for antagonistic, and five for additive when at least eight independent experiments were considered. In addition, the interactions of elevated [CO2 ] and warming had opposite effects on Ra and Rh, suggesting that different processes may influence their responses to the multifactor interactions. Our study highlights the crucial importance of the interactive effects among the multiple factors on Rs and its components, which could inform regional and global models to assess the climate-biosphere feedbacks and improve predictions of the future states of the ecological and climate systems. © 2016 John Wiley & Sons Ltd.

  18. Multiple bunch HOM evaluation for ERL cavities

    DOE PAGES

    Xu, Chen; Ben-Zvi, I.; Blaskiewicz, Michael M.; ...

    2017-06-15

    In this paper we investigate the effect of the bunch pattern in a linac on the Higher Order Mode (HOM) power generation. The future ERL-based electron–ion collider eRHIC at BNL is used as an illustrative example. This ERL has multiple high current Superconducting Radiofrequency (SRF) 5-cell cavities. The HOM power generated when a single bunch traverses the cavity is estimated by the corresponding loss factor. Multiple re-circulations through the Energy Recovery Linac (ERL) create a specific bunch pattern. In this case the loss factor can be different than the single bunch loss factor. HOM power can vary dramatically when themore » ERL bunch pattern changes. The HOM power generation can be surveyed in the time and frequency domains. We estimate the average HOM power in a 5-cell cavity with different ERL bunch patterns.« less

  19. Multiple bunch HOM evaluation for ERL cavities

    NASA Astrophysics Data System (ADS)

    Xu, Chen; Ben-Zvi, I.; Blaskiewicz, Michael M.; Hao, Yue; Ptitsyn, Vadim

    2017-09-01

    In this work we investigate the effect of the bunch pattern in a linac on the Higher Order Mode (HOM) power generation. The future ERL-based electron-ion collider eRHIC at BNL is used as an illustrative example. This ERL has multiple high current Superconducting Radiofrequency (SRF) 5-cell cavities. The HOM power generated when a single bunch traverses the cavity is estimated by the corresponding loss factor. Multiple re-circulations through the Energy Recovery Linac (ERL) create a specific bunch pattern. In this case the loss factor can be different than the single bunch loss factor. HOM power can vary dramatically when the ERL bunch pattern changes. The HOM power generation can be surveyed in the time and frequency domains. We estimate the average HOM power in a 5-cell cavity with different ERL bunch patterns.

  20. Multiple bunch HOM evaluation for ERL cavities

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

    Xu, Chen; Ben-Zvi, I.; Blaskiewicz, Michael M.

    In this paper we investigate the effect of the bunch pattern in a linac on the Higher Order Mode (HOM) power generation. The future ERL-based electron–ion collider eRHIC at BNL is used as an illustrative example. This ERL has multiple high current Superconducting Radiofrequency (SRF) 5-cell cavities. The HOM power generated when a single bunch traverses the cavity is estimated by the corresponding loss factor. Multiple re-circulations through the Energy Recovery Linac (ERL) create a specific bunch pattern. In this case the loss factor can be different than the single bunch loss factor. HOM power can vary dramatically when themore » ERL bunch pattern changes. The HOM power generation can be surveyed in the time and frequency domains. We estimate the average HOM power in a 5-cell cavity with different ERL bunch patterns.« less

  1. Simplifying Differential Equations for Multiscale Feynman Integrals beyond Multiple Polylogarithms.

    PubMed

    Adams, Luise; Chaubey, Ekta; Weinzierl, Stefan

    2017-04-07

    In this Letter we exploit factorization properties of Picard-Fuchs operators to decouple differential equations for multiscale Feynman integrals. The algorithm reduces the differential equations to blocks of the size of the order of the irreducible factors of the Picard-Fuchs operator. As a side product, our method can be used to easily convert the differential equations for Feynman integrals which evaluate to multiple polylogarithms to an ϵ form.

  2. Adolescents' multiple versus single primary attachment figures, reorganization of attachment hierarchy, and adjustments: the important people interview approach.

    PubMed

    Umemura, Tomotaka; Lacinová, Lenka; Kraus, Jakub; Horská, Eliška; Pivodová, Lenka

    2018-04-20

    Using 212 adolescents from a central-European country (mean age = 14.02, SD = 2.05, ranged from 11 to 18 years; females = 54%) and a multi-informant method to measure adolescents' behavioral and emotional adjustments, the present study explored three aspects regarding the attachment hierarchy. (1) The three types of behavioral systems of Rosenthal and Kobak's important people interview (IPI) were initially validated using an exploratory factor analysis with a US sample. Using a confirmatory factor analysis with a Czech sample, we replicated these three behavioral systems: attachment bond, support seeking, and affiliation. (2) We found that adolescents who developed attachment bond to multiple primary attachment figures were likely to score lower on both teacher-rated and parent-rated internalizing problems compared to those who had a single primary attachment figure. These multiple primary attachment figures tended to be family members (not peers). (3) Early adolescents who placed parents low in their attachment hierarchy scored higher on self-reported negative affect and lower on self-reported positive affect compared to early adolescents who placed parents high. The present study highlights multiple (vs. single) primary attachment figures as a protective factor and the premature reorganization of attachment hierarchy as a risk factor for adolescents' emotional and affective adjustments.

  3. Strategies for Coping in a Complex World: Adherence Behavior Among Older Adults with Chronic Illness

    PubMed Central

    Ross-Degnan, Dennis; Adams, Alyce S.; Safran, Dana Gelb; Soumerai, Stephen B.

    2007-01-01

    Background Increasing numbers of medicines increase nonadherence. Little is known about how older adults manage multiple medicines for multiple illnesses. Objectives To explore how older adults with multiple illnesses make choices about medicines. Design Semistructured interviews with older adults taking several medications. Accounts of respondents’ medicine-taking behavior were collected. Participants Twenty community-dwelling seniors with health insurance, in Eastern Massachusetts, aged 67–90, (4–12 medicines, 3–9 comorbidities). Approach Qualitative analysis using constant comparison to explain real choices made about medicines in the past (“historical”) and hypothetical (“future”) choices. Results Respondents reported both past (“historical”) choices and hypothetical (“future”) choices between medicines. Although people discussed effectiveness and future risk of the disease when prompted to prioritize their medicines (future choices), key factors leading to nonadherence (historical choices) were costs and side effects. Specific choices were generally dominated by 1 factor, and respondents rarely reported making explicit trade-offs between different factors. Factors affecting 1 choice were not necessarily the same as those affecting another choice in the same person. There was no evidence of “adherent” personalities. Conclusion Prescribing a new medicine, a change in provider or copayment can provoke new choices about both new and existing medications in older adults with multiple morbidities. PMID:17406952

  4. PTSD's factor structure and measurement invariance across subgroups with differing count of trauma types.

    PubMed

    Contractor, Ateka A; Caldas, Stephanie V; Dolan, Megan; Lagdon, Susan; Armour, Chérie

    2018-06-01

    To investigate the effect of the count of traumatizing event (TE) types on post-trauma mental health, several studies have compared posttraumatic stress disorder (PTSD) severity between individuals experiencing one versus multiple TE types. However, the validity of these studies depends on the establishment of measurement invariance of the construct(s) of interest. The current study examined the stability of the most optimal PTSD Model symptom cluster constructs (assessed by the PTSD Checklist for DSM-5 [PCL-5]) across subgroups experiencing one versus multiple TE types. The sample included university students (n = 556) endorsing at least one TE (Stressful Life Events Screening Questionnaire). Using data from the entire sample, results suggest that the PCL-5-assessed Hybrid Model provided a significantly better fit compared to other models. Results also indicated invariance of factor loadings (metric), and intercepts (scalar) for the PCL-5-assessed Hybrid Model factors across subgroups endorsing one (n = 191) versus multiple TE types (n = 365). Our findings thus support the stability, applicability, and meaningful comparison of the PCL-assessed Hybrid Model factor structure (including subscale severity scores) across subgroups experiencing one versus multiple TE types. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Should I stay or should I go? A prospective investigation examining individual factors impacting employment status among individuals with multiple sclerosis (MS).

    PubMed

    Strober, Lauren B; Chiaravalloti, Nancy; DeLuca, John

    2018-01-01

    Rates of unemployment among individuals with multiple sclerosis (MS) are as high as 80%. While several factors for such high rates of unemployment have been identified, they do not account for the majority of the variance. This study examines person-specific factors such as personality and coping, which may better account for individuals leaving the workforce. Forty individuals with MS (20 considering reducing work hours or leaving the workforce and 20 remaining employed) were matched on age, gender, education, disease duration, and disease course, and administered a comprehensive survey of factors purported to be related to employment status. Based on multiple, logistic regression analyses certain disease factors and person-specific factors differentiate those who are considering leaving work or reducing work hours and those staying employed. In particular, those expressing the need to reduce work hours or leaving the workforce reported more fatigue, anxiety, depression, and use of behavioral disengagement as a means of coping. In contrast, those staying employed reported greater levels of extraversion, self-efficacy, and use of humor as a means of coping. Together, fatigue, use of humor, and use of behavioral disengagement as a means of coping were the most significant factors, accounting for 44% of the variance. Findings suggest that greater consideration be given to these factors and that interventions tailored to address these factors may assist individuals with MS staying employed and/or making appropriate accommodations.

  6. Factor Structure of the Social Appearance Anxiety Scale in Turkish Early Adolescents

    ERIC Educational Resources Information Center

    Sahin, Ertugrul; Topkaya, Nursel

    2015-01-01

    Although the Social Appearance Anxiety Scale (SAAS) is most often validated with the use of confirmatory factor analysis (CFA) on undergraduate students, exploratory factor analysis and multiple factor retention decision criteria necessitate the analysis of underlying factor structure to prevent over and under factoring as well as to reveal…

  7. Competitive Stem Cell Recruitment by Multiple Cytotactic Cues

    PubMed Central

    Mendelson, Avital; Cheung, Yukkee; Paluch, Kamila; Chen, Mo; Kong, Kimi; Tan, Jiali; Dong, Ziming; Sia, Samuel K.; Mao, Jeremy J.

    2014-01-01

    A multitude of cytotactic cues direct cell migration in development, cancer metastasis and wound healing. However, our understanding of cell motility remains fragmented partially because current migration devices only allow the study of independent factors. We developed a cell motility assay that allows competitive recruitment of a given cell population simultaneously by gradients of multiple cytotactic cues, observable under real-time imaging. Well-defined uniform gradients of cytotactic cues can be independently generated and sustained in each channel. As a case study, bone marrow mesenchymal stem/stromal cells (MSCs) were exposed to 15 cytokines that are commonly present in arthritis. Cytokines that induced robust recruitment of MSCs in multiple groups were selected to ‘compete’ in a final round to yield the most chemotactic factor(s) based on cell migration numbers, distances, migration indices and motility over time. The potency of a given cytokine in competition frequently differed from its individual action, substantiating the need to test multiple cytokines concurrently due to synergistic or antagonistic effects. This new device has the rare capacity to screen molecules that induce cell migration in cancer therapy, drug development and tissue regeneration. PMID:23364311

  8. Building America Case Study: The Impact of Thermostat Placement in Low-Load Homes in Sunny Climates, Denver, Colorado

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

    Modern, energy-efficient homes conforming to the Zero Energy Ready Home standard face the challenge of meeting high customer expectations for comfort. Traditional heating, ventilation, and air conditioning (HVAC) sizing and control strategies may be insufficient to adequately condition each zone due to unique load patterns in each room caused by a number of factors. These factors include solar heat gains, occupant-related gains, and gains associated with appliances and electronics. Because of shrinking shell loads, these intermittent factors are having an increasingly significant impact on the thermal load in each zone. Consequently, occupant comfort can be compromised. To evaluate the impactmore » of climate and house geometry, as well as HVAC system and control strategies on comfort conditions, IBACOS analyzed the results of 99 TRNSYS multiple-zone simulations. The results of this analysis indicate that for simple-geometry and single-story plans, a single zone and thermostat can adequately condition the entire house. Demanding house geometry and houses with multiple stories require the consideration of multiple thermostats and multiple zones.« less

  9. Risk Assessment of Heating, Ventilating, and Air-Conditioning Strategies in Low-Load Homes

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

    Poerschke, Andrew

    2016-02-17

    "Modern, energy efficient homes conforming to the Zero Energy Ready Home standard face the challenge of meeting high customer expectations for comfort. Traditional heating, ventilation, and air conditioning (HVAC) sizing and control strategies may be insufficient to adequately condition each zone due to unique load patterns in each room caused by a number of factors. These factors include solar heat gains, occupant-related gains, and gains associated with appliances and electronics. Because of shrinking shell loads, these intermittent factors are having an increasingly significant impact on the thermal load in each zone. Consequently, occupant comfort can be compromised. To evaluate themore » impact of climate and house geometry, as well as HVAC system and control strategies on comfort conditions, IBACOS analyzed the results of 99 TRNSYS multiple-zone simulations. The results of this analysis indicate that for simple-geometry and single-story plans, a single zone and thermostat can adequately condition the entire house. Demanding house geometry and houses with multiple stories require the consideration of multiple thermostats and multiple zones.« less

  10. Second malignancies after multiple myeloma: from 1960s to 2010s

    PubMed Central

    Thomas, Anish; Mailankody, Sham; Korde, Neha; Kristinsson, Sigurdur Y.; Turesson, Ingemar

    2012-01-01

    Based on small numbers, recent reports from 3 randomized trials have consistently demonstrated more hematologic malignancies in patients treated with lenalidomide as maintenance (vs placebo). This fact has prompted concern and highlighted the association between multiple myeloma and second malignancies. Furthermore, an excess of acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) after multiple myeloma has been known for over 4 decades. Most prior studies have been restricted because of small numbers of patients, inadequate follow-up, and limitations of ascertainment of second malignancies. Although the underlying biologic mechanisms of AML/MDS after multiple myeloma are unknown, treatment-related factors are presumed to be responsible. Recently, an excess risk of AML/MDS was found among 5652 patients with IgG/IgA (but not IgM) monoclonal gammopathy of undetermined significance, supporting a role for disease-related factors. Furthermore, there is evidence to suggest that polymorphisms in germline genes may contribute to a person's susceptibility to subsequent cancers, whereas the potential influence of environmental and behavioral factors remains poorly understood. This review discusses current knowledge regarding second malignancies after multiple myeloma and gives future directions for efforts designed to characterize underlying biologic mechanisms, with the goal to maximize survival and minimize the risk for second malignancies for individual patients. PMID:22310913

  11. Female undergraduate fine arts students: a high-risk population for multiple sexual partners, unwanted pregnancy and sexually transmitted infections in China.

    PubMed

    Zou, Yuliang; Yan, Hong; Wu, Haocheng; Chen, Rucheng; Huang, Danqin; Li, Shiyue

    2013-04-01

    To compare risky sexual behaviour and risk factors associated with unwanted pregnancy and sexually transmitted infections (STIs) among female fine arts undergraduates and students of other disciplines in China. Anonymously completed questionnaires were received from 4769 unmarried female undergraduates, recruited using randomised cluster sampling. Multiple regression analyses were used to examine factors associated with lifetime number of sex partners, self-reported pregnancy, and STIs. The proportion of students who had ever had sex was higher among female fine arts majors (35%) than among other females (15%). Not using a condom at first sex (87%), multiple lifetime partners (44%), and extramarital lover now or ever in lifetime (9%) were more common in sexually experienced fine arts students. Self-reported pregnancy (23%) and STIs (33%) were also more common in fine arts students. Years spent in school, understanding or approval of multiple sex partners, younger age at first sex and coercive first sex were associated with multiple lifetime partners, which was a risk factor for both unintended pregnancy and STIs. Female fine arts students hold more tolerant attitudes toward sex than other female students. They were more inclined to risky sexual behaviours, and thus more vulnerable to unwanted pregnancy and STIs.

  12. Is This Kid a Likely Experimenter or a Likely Persister? An Analysis of Individual-Level and Family-Level Risk Factors Predicting Multiple Offending Among a Group of Adjudicated Youth.

    PubMed

    Buker, Hasan; Erbay, Ayhan

    2018-02-01

    To implement effective diversion programs and determine for a well-suited intervention strategy, ascertaining who, among the adjudicated youth, is more likely to involve in multiple offending, rather than desisting after an initial delinquent behavior, is of great significance. The overall objective of this study, therefore, is to contribute to the existing knowledge on assessing the risks for multiple offending during juvenile adjudication processes. In this regard, this study examined the predicting powers of several individual-level and family-level risk factors on multiple offending during adolescence, based on a data set derived from court-ordered social examination reports (SERs) on 400 adjudicated youth in Turkey. Two binomial regression models were implemented to test the predictor values of various risk factors from these two domains. Results indicated the following as significant predictors of multiple offending among the subjects: younger age of onset in delinquency, dropping out of school, having delinquent/drug abusing (risky) friends, being not able to share problems with the family, increased number of siblings, and having a domestically migrated family. Conclusively, these findings were compared with the existing literature, and the policy implications and recommendations for future research were discussed.

  13. Relationship between single and multiple perpetrator rape perpetration in South Africa: A comparison of risk factors in a population-based sample.

    PubMed

    R, Jewkes; Y, Sikweyiya; K, Dunkle; R, Morrell

    2015-07-07

    Studies of rape of women seldom distinguish between men's participation in acts of single and multiple perpetrator rape. Multiple perpetrator rape (MPR) occurs globally with serious consequences for women. In South Africa it is a cultural practice with defined circumstances in which it commonly occurs. Prevention requires an understanding of whether it is a context specific intensification of single perpetrator rape, or a distinctly different practice of different men. This paper aims to address this question. We conducted a cross-sectional household study with a multi-stage, randomly selected sample of 1686 men aged 18-49 who completed a questionnaire administered using an Audio-enhanced Personal Digital Assistant. We attempted to fit an ordered logistic regression model for factors associated with rape perpetration. 27.6 % of men had raped and 8.8 % had perpetrated multiple perpetrator rape (MPR). Thus 31.9 % of men who had ever raped had done so with other perpetrators. An ordered regression model was fitted, showing that the same associated factors, albeit at higher prevalence, are associated with SPR and MPR. Multiple perpetrator rape appears as an intensified form of single perpetrator rape, rather than a different form of rape. Prevention approaches need to be mainstreamed among young men.

  14. Cosmological constraints from multiple tracers in spectroscopic surveys

    NASA Astrophysics Data System (ADS)

    Alarcon, Alex; Eriksen, Martin; Gaztanaga, Enrique

    2018-01-01

    We use the Fisher matrix formalism to study the expansion and growth history of the Universe using galaxy clustering with 2D angular cross-correlation tomography in spectroscopic or high-resolution photometric redshift surveys. The radial information is contained in the cross-correlations between narrow redshift bins. We show how multiple tracers with redshift space distortions cancel sample variance and arbitrarily improve the constraints on the dark energy equation of state ω(z) and the growth parameter γ in the noiseless limit. The improvement for multiple tracers quickly increases with the bias difference between the tracers, up to a factor ∼4 in FoMγω. We model a magnitude limited survey with realistic density and bias using a conditional luminosity function, finding a factor 1.3-9.0 improvement in FoMγω - depending on global density - with a split in a halo mass proxy. Partly overlapping redshift bins improve the constraints in multiple tracer surveys a factor ∼1.3 in FoMγω. This finding also applies to photometric surveys, where the effect of using multiple tracers is magnified. We also show large improvement on the FoM with increasing density, which could be used as a trade-off to compensate some possible loss with radial resolution.

  15. 75 FR 58331 - Revision of Enforcement Procedures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-24

    ... recommended that TSA take these factors into account when TSA considers mitigating factors for purposes of... environment. Hence, TSA always considers multiple factors, including financial distress, when assessing civil... should be considered a mitigating factor for assessing penalties. Individuals who spend considerable time...

  16. Cognitive Affective Engagement Model of Multiple Source Use

    ERIC Educational Resources Information Center

    List, Alexandra; Alexander, Patricia A.

    2017-01-01

    This article introduces the cognitive affective engagement model (CAEM) of multiple source use. The CAEM is presented as a way of unifying cognitive and behaviorally focused models of multiple text engagement with research on the role of affective factors (e.g., interest) in text processing. The CAEM proposes that students' engagement with…

  17. Multiple Trajectories of Successful Aging of Older and Younger Cohorts

    ERIC Educational Resources Information Center

    Hsu, Hui-Chuan; Jones, Bobby L.

    2012-01-01

    Purpose: The purpose of this study was to apply group-based trajectory analysis to identify multiple successful aging trajectories by multiple indicators and to examine the factors related to successful aging among the elderly population in Taiwan. Design and Methods: Nation-representative longitudinal data collected from 1993 to 2007 and…

  18. Adherence to Medication Regimens among Low-Income Patients with Multiple Comorbid Chronic Conditions

    ERIC Educational Resources Information Center

    Mishra, Shiraz I.; Gioia, Deborah; Childress, Saltanat; Barnet, Beth; Webster, Ramothea L.

    2011-01-01

    This qualitative study sought to explore facilitators and barriers to adherence to multiple medications among low-income patients with comorbid chronic physical and mental health conditions. The 50 focus group participants identified personal/contextual and health system factors as major impediments to adherence to multiple medications. These…

  19. Equivalency for Father and Mother Ratings of the ADHD Symptoms

    ERIC Educational Resources Information Center

    Gomez, Rapson

    2010-01-01

    The study used multiple-group confirmatory factor analysis (CFA) and multiple indicators multiple causes (MIMIC) procedures to examine the measurement and construct equivalencies for father and mother ratings of ADHD symptoms, recoded as binary scores. Fathers (N = 387) and mothers (N = 411) rated their primary school-aged children on the…

  20. A Multiple Deficit Model of Reading Disability and Attention-Deficit/Hyperactivity Disorder: Searching for Shared Cognitive Deficits

    ERIC Educational Resources Information Center

    McGrath, Lauren M.; Pennington, Bruce F.; Shanahan, Michelle A.; Santerre-Lemmon, Laura E.; Barnard, Holly D.; Willcutt, Erik G.; DeFries, John C.; Olson, Richard K.

    2011-01-01

    Background: This study tests a multiple cognitive deficit model of reading disability (RD), attention-deficit/hyperactivity disorder (ADHD), and their comorbidity. Methods: A structural equation model (SEM) of multiple cognitive risk factors and symptom outcome variables was constructed. The model included phonological awareness as a unique…

  1. Interface and photoluminescence characteristics of graphene-(GaN/InGaN){sub n} multiple quantum wells hybrid structure

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

    Wang, Liancheng, E-mail: wanglc@semi.ac.cn, E-mail: lzq@semi.ac.cn, E-mail: zh.zhang@hebut.edu.cn; Semiconductor Lighting Technology Research and Development Center, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083; Mind Star

    The effects of graphene on the optical properties of active system, e.g., the InGaN/GaN multiple quantum wells, are thoroughly investigated and clarified. Here, we have investigated the mechanisms accounting for the photoluminescence reduction for the graphene covered GaN/InGaN multiple quantum wells hybrid structure. Compared to the bare multiple quantum wells, the photoluminescence intensity of graphene covered multiple quantum wells showed a 39% decrease after excluding the graphene absorption losses. The responsible mechanisms have been identified with the following factors: (1) the graphene two dimensional hole gas intensifies the polarization field in multiple quantum wells, thus steepening the quantum well bandmore » profile and causing hole-electron pairs to further separate; (2) a lower affinity of graphene compared to air leading to a weaker capability to confine the excited hot electrons in multiple quantum wells; and (3) exciton transfer through non-radiative energy transfer process. These factors are theoretically analysed based on advanced physical models of semiconductor devices calculations and experimentally verified by varying structural parameters, such as the indium fraction in multiple quantum wells and the thickness of the last GaN quantum barrier spacer layer.« less

  2. Incidence and related clinical factors of falls among older Chinese veterans in military communities: a prospective study.

    PubMed

    Xu, Wei; Chen, Da-Wei; Jin, Yan-Bin; Dong, Zhen-Jun; Zhang, Wei-Jiang; Chen, Jin-Wen; Yang, Shu-Mei; Wang, Jian-Rong

    2015-02-01

    [Purpose] The aim of this study was to determine fall incidence and explore clinical factors of falls among older Chinese veterans in military communities. [Subjects and Methods] We carried out a 12-month prospective study among 13 military communities in Beijing, China. Fall events were obtained by self-report to military community liaisons and monthly telephone interviews by researchers. [Results] Among the final sample of 447 older veterans, 86 fell once, 25 fell twice or more, and 152 falls occurred altogether. The incidence of falls and fallers were 342/1,000 person-years and 249/1,000 person-years. In Cox regression models, independent clinical factors associated with falls were visual acuity (RR=0.47), stroke (RR=2.43), lumbar diseases (RR=1.73), sedatives (RR=1.80), fall history in the past 6 months (RR=2.77), multiple chronic diseases (RR=1.53), multiple medications (RR=1.34), and five-repetition sit-to-stand test score (RR=1.41). Hearing acuity was close to being statistically significant. [Conclusion] The incidences of falls and fallers among older Chinese veterans were lower than those of Hong Kong and western countries. The clinical risk factors of falls were poor senses, stroke, lumbar diseases, taking sedatives, fall history in the past 6 months, having multiple chronic diseases, taking multiple medications, and poor physical function. The preventive strategies targeting the above risk factors are very significant for reducing falls.

  3. Incidence and related clinical factors of falls among older Chinese veterans in military communities: a prospective study

    PubMed Central

    Xu, Wei; Chen, Da-Wei; Jin, Yan-Bin; Dong, Zhen-Jun; Zhang, Wei-Jiang; Chen, Jin-Wen; Yang, Shu-Mei; Wang, Jian-Rong

    2015-01-01

    [Purpose] The aim of this study was to determine fall incidence and explore clinical factors of falls among older Chinese veterans in military communities. [Subjects and Methods] We carried out a 12-month prospective study among 13 military communities in Beijing, China. Fall events were obtained by self-report to military community liaisons and monthly telephone interviews by researchers. [Results] Among the final sample of 447 older veterans, 86 fell once, 25 fell twice or more, and 152 falls occurred altogether. The incidence of falls and fallers were 342/1,000 person-years and 249/1,000 person-years. In Cox regression models, independent clinical factors associated with falls were visual acuity (RR=0.47), stroke (RR=2.43), lumbar diseases (RR=1.73), sedatives (RR=1.80), fall history in the past 6 months (RR=2.77), multiple chronic diseases (RR=1.53), multiple medications (RR=1.34), and five-repetition sit-to-stand test score (RR=1.41). Hearing acuity was close to being statistically significant. [Conclusion] The incidences of falls and fallers among older Chinese veterans were lower than those of Hong Kong and western countries. The clinical risk factors of falls were poor senses, stroke, lumbar diseases, taking sedatives, fall history in the past 6 months, having multiple chronic diseases, taking multiple medications, and poor physical function. The preventive strategies targeting the above risk factors are very significant for reducing falls. PMID:25729162

  4. Endoscopic carpal tunnel release: a prospective analysis of factors associated with unsatisfactory results.

    PubMed

    Straub, T A

    1999-04-01

    The first 100 consecutive cases of endoscopic carpal tunnel release (ECTR) performed by the author were studied prospectively during 6 to 24 months follow-up. Various preoperative and postoperative factors were subjected to statistical analysis to determine possible associations with unsatisfactory results. Overall, 92% of hands had a satisfactory result from ECTR, although not all were rendered symptom-free. There were no significant complications. Preoperative factors associated with an increased likelihood of unsatisfactory results included hands with preoperative weakness, widened two-point discrimination, myofascial pain syndrome or fibromyalgia, involvement in litigation, multiple compressive neuropathies, or the presence of abnormal psychological factors. A trend to less satisfactory results was present in Workers' Compensation cases and patients with normal motor latencies on nerve conduction studies. Multiple postoperative factors correlated with unsatisfactory results.

  5. Metformin targets multiple signaling pathways in cancer.

    PubMed

    Lei, Yong; Yi, Yanhua; Liu, Yang; Liu, Xia; Keller, Evan T; Qian, Chao-Nan; Zhang, Jian; Lu, Yi

    2017-01-26

    Metformin, an inexpensive and well-tolerated oral agent commonly used in the first-line treatment of type 2 diabetes, has become the focus of intense research as a candidate anticancer agent. Here, we discuss the potential of metformin in cancer therapeutics, particularly its functions in multiple signaling pathways, including AMP-activated protein kinase, mammalian target of rapamycin, insulin-like growth factor, c-Jun N-terminal kinase/mitogen-activated protein kinase (p38 MAPK), human epidermal growth factor receptor-2, and nuclear factor kappaB pathways. In addition, cutting-edge targeting of cancer stem cells by metformin is summarized.

  6. Research in Evaluation Methods for Data Fusion-Capable Tactical Platforms and Distributed Multi-platform Systems in Electronic Warfare and Information-Warfare Related Missions

    DTIC Science & Technology

    2009-02-01

    They support their launches until both outside reds are killed or until second shots are needed. In the baseline scenario shown, US2 achieves 2 kills ...red 5/6 kills . The SUT gate multiplication factor was 5 and 15. The PE gate multiplication factors of 3 and 5, PE designs for Vogel and Hungarian... ploughed in various sections of this land by splitting it into sub plots came to be known as the subplot factor. Such a design is used only when there

  7. Analysis of the Environmental Management System based on ISO 14001 on the American continent.

    PubMed

    Neves, Fábio de Oliveira; Salgado, Eduardo G; Beijo, Luiz A

    2017-09-01

    The American continent is in broad economic and industrial development. Consequently, a more detailed discussion of the impacts generated by such development is needed. Moreover, there is an increase in the number of ISO 14001 certificates issued to this continent. Given the above, no studies were found that bridge the gap to identify the influence of different factors on ISO 14001 in the Americas. Thus, this article has as its main aim to check which economic, environmental and cultural factors have influence on ISO 14001 Certification in the American Continent. The data were collected in the ISO Survey, World Bank, United Nations Development Programme and International Energy Agency. Among the countries of that continent, thirteen were analyzed and only two did not show the economic factors as the influence factor in the multiple regression models fitted with Brazil and the United State. In these models, all presented environmental factors as influencing factors. Only in Brazil the index HDI presented as cultural factor in multiple regression model fitted. The economic factors: Gross Domestic Product and exports of goods and services and environmental: Carbon Dioxide (CO 2 ) and fossil fuel consumption were the most influential in ISO 14001 certification. Venezuela, Uruguay, Colombia and the United States were countries that had factors dependent on each other, featuring the environmental marketing. Briefly, this study brings up several implications: to the academy, with the proposal of new concepts and guidance on the factors that assist in ISO 14001 certification in the American Continent. Additionally, taking into account the industry, the factors serve as efficiency parameters for the implementation of ISO 14001 standard, and for the Government to improve through factors that do not fit in multiple regression models. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Combined influence of multiple climatic factors on the incidence of bacterial foodborne diseases.

    PubMed

    Park, Myoung Su; Park, Ki Hwan; Bahk, Gyung Jin

    2018-01-01

    Information regarding the relationship between the incidence of foodborne diseases (FBD) and climatic factors is useful in designing preventive strategies for FBD based on anticipated future climate change. To better predict the effect of climate change on foodborne pathogens, the present study investigated the combined influence of multiple climatic factors on bacterial FBD incidence in South Korea. During 2011-2015, the relationships between 8 climatic factors and the incidences of 13 bacterial FBD, were determined based on inpatient stays, on a monthly basis using the Pearson correlation analyses, multicollinearity tests, principal component analysis (PCA), and the seasonal autoregressive integrated moving average (SARIMA) modeling. Of the 8 climatic variables, the combination of temperature, relative humidity, precipitation, insolation, and cloudiness was significantly associated with salmonellosis (P<0.01), vibriosis (P<0.05), and enterohemorrhagic Escherichia coli O157:H7 infection (P<0.01). The combined effects of snowfall, wind speed, duration of sunshine, and cloudiness were not significant for these 3 FBD. Other FBD, including campylobacteriosis, were not significantly associated with any combination of climatic factors. These findings indicate that the relationships between multiple climatic factors and bacterial FBD incidence can be valuable for the development of prediction models for future patterns of diseases in response to changes in climate. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Use of factor scores for predicting body weight from linear body measurements in three South African indigenous chicken breeds.

    PubMed

    Malomane, Dorcus Kholofelo; Norris, David; Banga, Cuthbert B; Ngambi, Jones W

    2014-02-01

    Body weight and weight of body parts are of economic importance. It is difficult to directly predict body weight from highly correlated morphological traits through multiple regression. Factor analysis was carried out to examine the relationship between body weight and five linear body measurements (body length, body girth, wing length, shank thickness, and shank length) in South African Venda (VN), Naked neck (NN), and Potchefstroom koekoek (PK) indigenous chicken breeds, with a view to identify those factors that define body conformation. Multiple regression was subsequently performed to predict body weight, using orthogonal traits derived from the factor analysis. Measurements were obtained from 210 chickens, 22 weeks of age, 70 chickens per breed. High correlations were obtained between body weight and all body measurements except for wing length in PK. Two factors extracted after varimax rotation explained 91, 95, and 83% of total variation in VN, NN, and PK, respectively. Factor 1 explained 73, 90, and 64% in VN, NN, and PK, respectively, and was loaded on all body measurements except for wing length in VN and PK. In a multiple regression, these two factors accounted for 72% variation in body weight in VN, while only factor 1 accounted for 83 and 74% variation in body weight in NN and PK, respectively. The two factors could be used to define body size and conformation of these breeds. Factor 1 could predict body weight in all three breeds. Body measurements can be better selected jointly to improve body weight in these breeds.

  10. Featured Article: Serum [Met5]-enkephalin levels are reduced in multiple sclerosis and restored by low-dose naltrexone.

    PubMed

    Ludwig, Michael D; Zagon, Ian S; McLaughlin, Patricia J

    2017-09-01

    Low-dose naltrexone is a widely used off-label therapeutic prescribed for a variety of immune-related disorders. The mechanism underlying low-dose naltrexone's efficacy for fatigue, Crohn's disease, fibromyalgia, and multiple sclerosis is, in part, intermittent blockade of opioid receptors followed by upregulation of endogenous opioids. Short, intermittent blockade by naltrexone specifically blocks the opioid growth factor receptor resulting in biofeedback events that increase production of the endogenous opioid growth factor (OGF) (chemically termed [Met 5 ]-enkephalin) facilitating interactions between opioid growth factor and opioid growth factor receptor that ultimately, result in inhibited cell proliferation. Preclinical studies have reported that enkephalin levels are deficient in animal models of experimental autoimmune encephalomyelitis, a mouse model of multiple sclerosis. Our hypothesis is that serum enkephalin levels are diminished in humans with multiple sclerosis and experimental autoimmune encephalomyelitis mice, and that change in serum opioid growth factor levels may serve as a reasonable candidate biomarker for the onset of experimental autoimmune encephalomyelitis and response to therapy. To address this, we designed a two-part study to measure endogenous opioids in multiple sclerosis patients, and to investigate the temporal pattern of decline in serum enkephalin concentrations in mice with chronic progressive experimental autoimmune encephalomyelitis and treated with low-dose naltrexone. For comparison, we investigated whether low-dose naltrexone exposure in normal mice also resulted in altered enkephalin levels. In both animal models, we monitored tactile and heat sensitivity, as well as differential white blood cell counts as indicators of inflammation. Serum [Met 5 ]-enkephalin levels were lower in humans with multiple sclerosis relative to non-multiple sclerosis patients, and low-dose naltrexone restored their levels. In experimental autoimmune encephalomyelitis mice, [Met 5 ]-enkephalin levels were depressed prior to the appearance of clinical disease, and were restored with low-dose naltrexone treatment. Low-dose naltrexone therapy had no effect on serum [Met 5 ]-enkephalin or β-endorphin in normal mice. Thus, [Met 5 ]-enkephalin (i.e. opioid growth factor) may be a reasonable candidate biomarker for multiple sclerosis, and may signal new pathways for treatment of autoimmune disorders. Impact statement This report presents human and animal data identifying a novel biomarker for the onset and progression of multiple sclerosis (MS). Humans diagnosed with MS have reduced serum levels of OGF (i.e. [Met 5 ]-enkephalin) relative to non-MS neurologic patients, and low-dose naltrexone (LDN) therapy restored their enkephalin levels. Serum OGF levels were reduced in mice immunized with MOG 35-55 prior to any clinical behavioral sign of experimental autoimmune encephalomyelitis, and LDN therapy restored their serum OGF levels. β-endorphin concentrations were not altered by LDN in humans or mice. Thus, blood levels of OGF may serve as a new, selective biomarker for the progression of MS, as well as response to therapy.

  11. Does the Assessment of Recovery Capital scale reflect a single or multiple domains?

    PubMed

    Arndt, Stephan; Sahker, Ethan; Hedden, Suzy

    2017-01-01

    The goal of this study was to determine whether the 50-item Assessment of Recovery Capital scale represents a single general measure or whether multiple domains might be psychometrically useful for research or clinical applications. Data are from a cross-sectional de-identified existing program evaluation information data set with 1,138 clients entering substance use disorder treatment. Principal components and iterated factor analysis were used on the domain scores. Multiple group factor analysis provided a quasi-confirmatory factor analysis. The solution accounted for 75.24% of the total variance, suggesting that 10 factors provide a reasonably good fit. However, Tucker's congruence coefficients between the factor structure and defining weights (0.41-0.52) suggested a poor fit to the hypothesized 10-domain structure. Principal components of the 10-domain scores yielded one factor whose eigenvalue was greater than one (5.93), accounting for 75.8% of the common variance. A few domains had perceptible but small unique variance components suggesting that a few of the domains may warrant enrichment. Our findings suggest that there is one general factor, with a caveat. Using the 10 measures inflates the chance for Type I errors. Using one general measure avoids this issue, is simple to interpret, and could reduce the number of items. However, those seeking to maximally predict later recovery success may need to use the full instrument and all 10 domains.

  12. Use of multiple picosecond high-mass molecular dynamics simulations to predict crystallographic B-factors of folded globular proteins.

    PubMed

    Pang, Yuan-Ping

    2016-09-01

    Predicting crystallographic B-factors of a protein from a conventional molecular dynamics simulation is challenging, in part because the B-factors calculated through sampling the atomic positional fluctuations in a picosecond molecular dynamics simulation are unreliable, and the sampling of a longer simulation yields overly large root mean square deviations between calculated and experimental B-factors. This article reports improved B-factor prediction achieved by sampling the atomic positional fluctuations in multiple picosecond molecular dynamics simulations that use uniformly increased atomic masses by 100-fold to increase time resolution. Using the third immunoglobulin-binding domain of protein G, bovine pancreatic trypsin inhibitor, ubiquitin, and lysozyme as model systems, the B-factor root mean square deviations (mean ± standard error) of these proteins were 3.1 ± 0.2-9 ± 1 Å 2 for Cα and 7.3 ± 0.9-9.6 ± 0.2 Å 2 for Cγ, when the sampling was done for each of these proteins over 20 distinct, independent, and 50-picosecond high-mass molecular dynamics simulations with AMBER forcefield FF12MC or FF14SB. These results suggest that sampling the atomic positional fluctuations in multiple picosecond high-mass molecular dynamics simulations may be conducive to a priori prediction of crystallographic B-factors of a folded globular protein.

  13. The Business Policy Course: Multiple Methods for Multiple Goals.

    ERIC Educational Resources Information Center

    Thomas, Anisya S.

    1998-01-01

    Outlines the objectives of a capstone business policy and strategy course; the use of case analysis, article critiques, storytelling, and computer simulation; and contextual factors in matching objectives and methods. (SK)

  14. Sensory mediation of stimulus-driven attentional capture in multiple-cue displays.

    PubMed

    Wright, Richard D; Richard, Christian M

    2003-08-01

    Three location-cuing experiments were conducted in order to examine the stimulus-driven control of attentional capture in multiple-cue displays. These displays consisted of one to four simultaneously presented direct location cues. The results indicated that direct location cuing can produce cue effects that are mediated, in part, by nonattentional processing that occurs simultaneously at multiple locations. When single cues were presented in isolation, however, the resulting cue effect appeared to be due to a combination of sensory processing and attentional capture by the cue. This suggests that the faster responses produced by direct cues may be associated with two different components: an attention-related component that can be modulated by goal-driven factors and a nonattentional component that occurs in parallel at multiple direct-cue locations and is minimally affected by goal-driven factors.

  15. [Effect of pharmacologic treatment of the nutritional status of neurologic patients].

    PubMed

    Piñeiro Corrales, Guadalupe; Vázquez López, Cristina; Álvarez Payero, Miriam

    2014-01-01

    Clinical manifestations accompanying neurological diseases are diverse and affect multiple organs. Nutritional status of patients with certain neurological diseases such as stroke, Alzheimer's disease, Parkinson's disease, Epilepsy and Multiple Sclerosis can be altered because of symptoms associated with disease course, including certain micronutrient deficiency (folic acid, zinc, vitamin B6 and B12, vitamin D, vitamin E and vitamin C), changes in energy expenditure, intake decreased, gastrointestinal disorders and dysfunction of the bone mass. Also, we have to take in account other factors as: advanced age, multiple co morbidities, polypharmacy, the use of herbal products, social habits, diet and pharmacological treatments effect. An assessment of the factors related to neurological treatment that cause alterations in metabolic and nutritional status was performed: side effects of anti-Parkinson drugs, antiepileptic drugs, and multiple sclerosis drugs; drug-nutrient interactions; and nutrient-drug interactions.

  16. Serum levels of brain-derived neurotrophic factor (BNDF) in multiple sclerosis patients with Trichuris suis ova therapy.

    PubMed

    Rosche, Berit; Werner, Jonas; Benzel, Friderike Joëlle; Harms, Lutz; Danker-Hopfe, Heidi; Hellweg, Rainer

    2013-01-01

    We previously analysed clinical and immunological parameters under Trichuris suis ova (TSO) therapy in four patients with secondary progressive multiple sclerosis. The serum Brain-derived neurotrophic factor (BDNF) levels of these four patients were assessed before, during and after therapy with TSO and showed significant decrease of BDNF during TSO therapy (p < 0.05). © B. Rosche et al., published by EDP Sciences, 2013.

  17. An efficient approach to understanding and predicting the effects of multiple task characteristics on performance.

    PubMed

    Richardson, Miles

    2017-04-01

    In ergonomics there is often a need to identify and predict the separate effects of multiple factors on performance. A cost-effective fractional factorial approach to understanding the relationship between task characteristics and task performance is presented. The method has been shown to provide sufficient independent variability to reveal and predict the effects of task characteristics on performance in two domains. The five steps outlined are: selection of performance measure, task characteristic identification, task design for user trials, data collection, regression model development and task characteristic analysis. The approach can be used for furthering knowledge of task performance, theoretical understanding, experimental control and prediction of task performance. Practitioner Summary: A cost-effective method to identify and predict the separate effects of multiple factors on performance is presented. The five steps allow a better understanding of task factors during the design process.

  18. A multiple indicator, multiple cause method for representing social capital with an application to psychological distress

    NASA Astrophysics Data System (ADS)

    Congdon, Peter

    2010-03-01

    This paper describes a structural equation methodology for obtaining social capital scores for survey subjects from multiple indicators of social support, neighbourhood and trust perceptions, and memberships of organizations. It adjusts for variation that is likely to occur in levels of social capital according to geographic context (e.g. level of area deprivation, geographic region, level of urbanity) and demographic group. Social capital is used as an explanatory factor for psychological distress using data from the 2006 Health Survey for England. A highly significant effect of social capital in reducing the chance of psychiatric caseness is obtained after controlling for other individual and geographic risk factors. Allowing for social capital has considerable effects on the impacts on psychiatric health of other risk factors. In particular, the impact of area deprivation category is much reduced. There is also evidence of significant differentiation in social capital between population categories and geographic contexts.

  19. Statistical significance of combinatorial regulations

    PubMed Central

    Terada, Aika; Okada-Hatakeyama, Mariko; Tsuda, Koji; Sese, Jun

    2013-01-01

    More than three transcription factors often work together to enable cells to respond to various signals. The detection of combinatorial regulation by multiple transcription factors, however, is not only computationally nontrivial but also extremely unlikely because of multiple testing correction. The exponential growth in the number of tests forces us to set a strict limit on the maximum arity. Here, we propose an efficient branch-and-bound algorithm called the “limitless arity multiple-testing procedure” (LAMP) to count the exact number of testable combinations and calibrate the Bonferroni factor to the smallest possible value. LAMP lists significant combinations without any limit, whereas the family-wise error rate is rigorously controlled under the threshold. In the human breast cancer transcriptome, LAMP discovered statistically significant combinations of as many as eight binding motifs. This method may contribute to uncover pathways regulated in a coordinated fashion and find hidden associations in heterogeneous data. PMID:23882073

  20. Case-control analysis in highway safety: Accounting for sites with multiple crashes.

    PubMed

    Gross, Frank

    2013-12-01

    There is an increased interest in the use of epidemiological methods in highway safety analysis. The case-control and cohort methods are commonly used in the epidemiological field to identify risk factors and quantify the risk or odds of disease given certain characteristics and factors related to an individual. This same concept can be applied to highway safety where the entity of interest is a roadway segment or intersection (rather than a person) and the risk factors of interest are the operational and geometric characteristics of a given roadway. One criticism of the use of these methods in highway safety is that they have not accounted for the difference between sites with single and multiple crashes. In the medical field, a disease either occurs or it does not; multiple occurrences are generally not an issue. In the highway safety field, it is necessary to evaluate the safety of a given site while accounting for multiple crashes. Otherwise, the analysis may underestimate the safety effects of a given factor. This paper explores the use of the case-control method in highway safety and two variations to account for sites with multiple crashes. Specifically, the paper presents two alternative methods for defining cases in a case-control study and compares the results in a case study. The first alternative defines a separate case for each crash in a given study period, thereby increasing the weight of the associated roadway characteristics in the analysis. The second alternative defines entire crash categories as cases (sites with one crash, sites with two crashes, etc.) and analyzes each group separately in comparison to sites with no crashes. The results are also compared to a "typical" case-control application, where the cases are simply defined as any entity that experiences at least one crash and controls are those entities without a crash in a given period. In a "typical" case-control design, the attributes associated with single-crash segments are weighted the same as the attributes of segments with multiple crashes. The results support the hypothesis that the "typical" case-control design may underestimate the safety effects of a given factor compared to methods that account for sites with multiple crashes. Compared to the first alternative case definition (where multiple crash segments represent multiple cases) the results from the "typical" case-control design are less pronounced (i.e., closer to unity). The second alternative (where case definitions are constructed for various crash categories and analyzed separately) provides further evidence that sites with single and multiple crashes should not be grouped together in a case-control analysis. This paper indicates a clear need to differentiate sites with single and multiple crashes in a case-control analysis. While the results suggest that sites with multiple crashes can be accounted for using a case-control design, further research is needed to determine the optimal method for addressing this issue. This paper provides a starting point for that research. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Integrated modeling and analysis of the multiple electromechanical couplings for the direct driven feed system in machine tools

    NASA Astrophysics Data System (ADS)

    Yang, Xiaojun; Lu, Dun; Liu, Hui; Zhao, Wanhua

    2018-06-01

    The complicated electromechanical coupling phenomena due to different kinds of causes have significant influences on the dynamic precision of the direct driven feed system in machine tools. In this paper, a novel integrated modeling and analysis method of the multiple electromechanical couplings for the direct driven feed system in machine tools is presented. At first, four different kinds of electromechanical coupling phenomena in the direct driven feed system are analyzed systematically. Then a novel integrated modeling and analysis method of the electromechanical coupling which is influenced by multiple factors is put forward. In addition, the effects of multiple electromechanical couplings on the dynamic precision of the feed system and their main influencing factors are compared and discussed, respectively. Finally, the results of modeling and analysis are verified by the experiments. It finds out that multiple electromechanical coupling loops, which are overlapped and influenced by each other, are the main reasons of the displacement fluctuations in the direct driven feed system.

  2. Comparing Factor Structures of Adolescent Psychopathology

    ERIC Educational Resources Information Center

    Verona, Edelyn; Javdani, Shabnam; Sprague, Jenessa

    2011-01-01

    Research on the structure of adolescent psychopathology can provide information on broad factors that underlie different forms of maladjustment in youths. Multiple studies from the literature on adult populations suggest that 2 factors, Internalizing and Externalizing, meaningfully comprise the factor structure of adult psychopathology (e.g.,…

  3. Reconstruction and topological characterization of the sigma factor regulatory network of Mycobacterium tuberculosis

    PubMed Central

    Chauhan, Rinki; Ravi, Janani; Datta, Pratik; Chen, Tianlong; Schnappinger, Dirk; Bassler, Kevin E.; Balázsi, Gábor; Gennaro, Maria Laura

    2016-01-01

    Accessory sigma factors, which reprogram RNA polymerase to transcribe specific gene sets, activate bacterial adaptive responses to noxious environments. Here we reconstruct the complete sigma factor regulatory network of the human pathogen Mycobacterium tuberculosis by an integrated approach. The approach combines identification of direct regulatory interactions between M. tuberculosis sigma factors in an E. coli model system, validation of selected links in M. tuberculosis, and extensive literature review. The resulting network comprises 41 direct interactions among all 13 sigma factors. Analysis of network topology reveals (i) a three-tiered hierarchy initiating at master regulators, (ii) high connectivity and (iii) distinct communities containing multiple sigma factors. These topological features are likely associated with multi-layer signal processing and specialized stress responses involving multiple sigma factors. Moreover, the identification of overrepresented network motifs, such as autoregulation and coregulation of sigma and anti-sigma factor pairs, provides structural information that is relevant for studies of network dynamics. PMID:27029515

  4. Listening to food workers: Factors that impact proper health and hygiene practice in food service.

    PubMed

    Clayton, Megan L; Clegg Smith, Katherine; Neff, Roni A; Pollack, Keshia M; Ensminger, Margaret

    2015-01-01

    Foodborne disease is a significant problem worldwide. Research exploring sources of outbreaks indicates a pronounced role for food workers' improper health and hygiene practice. To investigate food workers' perceptions of factors that impact proper food safety practice. Interviews with food service workers in Baltimore, MD, USA discussing food safety practices and factors that impact implementation in the workplace. A social ecological model organizes multiple levels of influence on health and hygiene behavior. Issues raised by interviewees include factors across the five levels of the social ecological model, and confirm findings from previous work. Interviews also reveal many factors not highlighted in prior work, including issues with food service policies and procedures, working conditions (e.g., pay and benefits), community resources, and state and federal policies. Food safety interventions should adopt an ecological orientation that accounts for factors at multiple levels, including workers' social and structural context, that impact food safety practice.

  5. Predicting homophobic behavior among heterosexual youth: domain general and sexual orientation-specific factors at the individual and contextual level.

    PubMed

    Poteat, V Paul; DiGiovanni, Craig D; Scheer, Jillian R

    2013-03-01

    As a form of bias-based harassment, homophobic behavior remains prominent in schools. Yet, little attention has been given to factors that underlie it, aside from bullying and sexual prejudice. Thus, we examined multiple domain general (empathy, perspective-taking, classroom respect norms) and sexual orientation-specific factors (sexual orientation identity importance, number of sexual minority friends, parents' sexual minority attitudes, media messages). We documented support for a model in which these sets of factors converged to predict homophobic behavior, mediated through bullying and prejudice, among 581 students in grades 9-12 (55 % female). The structural equation model indicated that, with the exception of media messages, these additional factors predicted levels of prejudice and bullying, which in turn predicted the likelihood of students to engage in homophobic behavior. These findings highlight the importance of addressing multiple interrelated factors in efforts to reduce bullying, prejudice, and discrimination among youth.

  6. The MCNP6 Analytic Criticality Benchmark Suite

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

    Brown, Forrest B.

    2016-06-16

    Analytical benchmarks provide an invaluable tool for verifying computer codes used to simulate neutron transport. Several collections of analytical benchmark problems [1-4] are used routinely in the verification of production Monte Carlo codes such as MCNP® [5,6]. Verification of a computer code is a necessary prerequisite to the more complex validation process. The verification process confirms that a code performs its intended functions correctly. The validation process involves determining the absolute accuracy of code results vs. nature. In typical validations, results are computed for a set of benchmark experiments using a particular methodology (code, cross-section data with uncertainties, and modeling)more » and compared to the measured results from the set of benchmark experiments. The validation process determines bias, bias uncertainty, and possibly additional margins. Verification is generally performed by the code developers, while validation is generally performed by code users for a particular application space. The VERIFICATION_KEFF suite of criticality problems [1,2] was originally a set of 75 criticality problems found in the literature for which exact analytical solutions are available. Even though the spatial and energy detail is necessarily limited in analytical benchmarks, typically to a few regions or energy groups, the exact solutions obtained can be used to verify that the basic algorithms, mathematics, and methods used in complex production codes perform correctly. The present work has focused on revisiting this benchmark suite. A thorough review of the problems resulted in discarding some of them as not suitable for MCNP benchmarking. For the remaining problems, many of them were reformulated to permit execution in either multigroup mode or in the normal continuous-energy mode for MCNP. Execution of the benchmarks in continuous-energy mode provides a significant advance to MCNP verification methods.« less

  7. Potential Factors Affecting Survival Differ by Run-Timing and Location: Linear Mixed-Effects Models of Pacific Salmonids (Oncorhynchus spp.) in the Klamath River, California

    PubMed Central

    Quiñones, Rebecca M.; Holyoak, Marcel; Johnson, Michael L.; Moyle, Peter B.

    2014-01-01

    Understanding factors influencing survival of Pacific salmonids (Oncorhynchus spp.) is essential to species conservation, because drivers of mortality can vary over multiple spatial and temporal scales. Although recent studies have evaluated the effects of climate, habitat quality, or resource management (e.g., hatchery operations) on salmonid recruitment and survival, a failure to look at multiple factors simultaneously leaves open questions about the relative importance of different factors. We analyzed the relationship between ten factors and survival (1980–2007) of four populations of salmonids with distinct life histories from two adjacent watersheds (Salmon and Scott rivers) in the Klamath River basin, California. The factors were ocean abundance, ocean harvest, hatchery releases, hatchery returns, Pacific Decadal Oscillation, North Pacific Gyre Oscillation, El Niño Southern Oscillation, snow depth, flow, and watershed disturbance. Permutation tests and linear mixed-effects models tested effects of factors on survival of each taxon. Potential factors affecting survival differed among taxa and between locations. Fall Chinook salmon O. tshawytscha survival trends appeared to be driven partially or entirely by hatchery practices. Trends in three taxa (Salmon River spring Chinook salmon, Scott River fall Chinook salmon; Salmon River summer steelhead trout O. mykiss) were also likely driven by factors subject to climatic forcing (ocean abundance, summer flow). Our findings underscore the importance of multiple factors in simultaneously driving population trends in widespread species such as anadromous salmonids. They also show that the suite of factors may differ among different taxa in the same location as well as among populations of the same taxa in different watersheds. In the Klamath basin, hatchery practices need to be reevaluated to protect wild salmonids. PMID:24866173

  8. Measuring social desirability across language and sex: A comparison of Marlowe-Crowne Social Desirability Scale factor structures in English and Mandarin Chinese in Malaysia.

    PubMed

    Kurz, A Solomon; Drescher, Christopher F; Chin, Eu Gene; Johnson, Laura R

    2016-06-01

    Malaysia is a Southeast Asian country in which multiple languages are prominently spoken, including English and Mandarin Chinese. As psychological science continues to develop within Malaysia, there is a need for psychometrically sound instruments that measure psychological phenomena in multiple languages. For example, assessment tools for measuring social desirability could be a useful addition in psychological assessments and research studies in a Malaysian context. This study examined the psychometric performance of the English and Mandarin Chinese versions of the Marlowe-Crowne Social Desirability Scale when used in Malaysia. Two hundred and eighty-three students (64% female; 83% Chinese, 9% Indian) from two college campuses completed the Marlowe-Crowne Social Desirability Scale in their language of choice (i.e., English or Mandarin Chinese). Proposed factor structures were compared with confirmatory factor analysis, and multiple indicators-multiple causes models were used to examine measurement invariance across language and sex. Factor analyses supported a two-factor structure (i.e., Attribution and Denial) for the measure. Invariance tests revealed the scale was invariant by sex, indicating that social desirability can be interpreted similarly across sex. The scale was partially invariant by language version, with some non-invariance observed within the Denial factor. Non-invariance may be related to differences in the English and Mandarin Chinese languages, as well as cultural differences. Directions for further research include examining the measurement of social desirability in other contexts where both English and Mandarin Chinese are spoken (i.e., China) and further examining the causes of non-invariance on specific items. © 2016 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  9. Using Module Analysis for Multiple Choice Responses: A New Method Applied to Force Concept Inventory Data

    ERIC Educational Resources Information Center

    Brewe, Eric; Bruun, Jesper; Bearden, Ian G.

    2016-01-01

    We describe "Module Analysis for Multiple Choice Responses" (MAMCR), a new methodology for carrying out network analysis on responses to multiple choice assessments. This method is used to identify modules of non-normative responses which can then be interpreted as an alternative to factor analysis. MAMCR allows us to identify conceptual…

  10. Update on Multiple Ovulations in Dairy Cattle.

    PubMed

    Macmillan, Kira; Kastelic, John P; Colazo, Marcos G

    2018-04-24

    This review updates the causal mechanisms and risk factors for multiple ovulations (MOV) in cattle. Clearly, MOV can lead to twin pregnancies, which negatively affects the health, production, and reproduction of cows. Therefore, a better understanding of the factors causing MOV may help to reduce twinning. Multiple ovulations occur after two or more follicles deviate and achieve codominance. The MOV rate is influenced by a complex network of hormones. For example, MOV is more common during periods of low progesterone (P4), that is, in anovulatory cattle or when luteolysis coincides with the selection of the future ovulatory follicle. There is also strong evidence for the luteinizing hormone (LH) being the primary factor leading to codominance, as high P4 concentrations suppress the transient LH surges and can reduce the ovulation rate in cattle or even inhibit deviation. Rates of MOV are increased in older and higher-producing dairy cows. Increased milk production and dry matter intake (DMI) increases hormone clearance, including P4; however, the association between milk yield and MOV has not been consistent. Additional risk factors for MOV include ovarian cysts, diet, season, and genetics.

  11. A microfluidic chip containing multiple 3D nanofibrous scaffolds for culturing human pluripotent stem cells

    NASA Astrophysics Data System (ADS)

    Wertheim, Lior; Shapira, Assaf; Amir, Roey J.; Dvir, Tal

    2018-04-01

    In microfluidics-based lab-on-a-chip systems, which are used for investigating the effect of drugs and growth factors on cells, the latter are usually cultured within the device’s channels in two-dimensional, and not in their optimal three-dimensional (3D) microenvironment. Herein, we address this shortfall by designing a microfluidic system, comprised of two layers. The upper layer of the system consists of multiple channels generating a gradient of soluble factors. The lower layer is comprised of multiple wells, each deposited with 3D, nanofibrous scaffold. We first used a mathematical model to characterize the fluid flow within the system. We then show that induced pluripotent stem cells can be seeded within the 3D scaffolds and be exposed to a well-mixed gradient of soluble factors. We believe that utilizing such system may enable in the future to identify new differentiation factors, investigate drug toxicity, and eventually allow to perform analyses on patient-specific tissues, in order to fit the appropriate combination and concentration of drugs.

  12. Multiple Levels of Family Factors and Oppositional Defiant Disorder Symptoms Among Chinese Children.

    PubMed

    Lin, Xiuyun; Li, Longfeng; Heath, Melissa A; Chi, Peilian; Xu, Shousen; Fang, Xiaoyi

    2018-03-01

    Family factors are closely associated with child developmental outcomes. This study examined the relationship of oppositional defiant disorder (ODD) symptoms and factors at whole family, dyadic, and individual levels in Chinese children. Participants, who were recruited from 14 primary schools in north, east, and south-west China, included 80 father-child dyads and 169 mother-child dyads. Children in the participating dyads were previously diagnosed with ODD. Results revealed that family cohesion/adaptability was indirectly associated with ODD symptoms via parent-child relationship and child emotion regulation. Parent-child relationship affected ODD symptoms directly and indirectly through child emotion regulation. In addition, the effects of family cohesion/adaptability on parent emotion regulation and child emotion regulation were mediated by the parent-child relationship. The tested model provides a comprehensive framework of how family factors at multiple levels are related to child ODD symptoms and highlights the importance of understanding child emotional and behavioral problems within the family context, more specifically within the multiple levels of family relationships. © 2016 Family Process Institute.

  13. Multiple risk factors during pregnancy in South Africa: the need for a horizontal approach to perinatal care.

    PubMed

    Tomlinson, Mark; O'Connor, Mary J; le Roux, Ingrid M; Stewart, Jacqueline; Mbewu, Nokwanele; Harwood, Jessica; Rotheram-Borus, Mary Jane

    2014-06-01

    South African children's long-term health and well-being is jeopardized during their mothers' pregnancies by the intersecting epidemics of HIV, alcohol use, low birth weight (LBW; <2,500 g) related to poor nutrition, and depressed mood. This research examines these overlapping risk factors among 1,145 pregnant Xhosa women living in 24 township neighborhoods in Cape Town, South Africa. Results revealed that 66 % of pregnant women experienced at least one risk factor. In descending order of prevalence, 37 % reported depressed mood, 29 % were HIV+, 25 % used alcohol prior to knowing that they were pregnant, and 15 % had a previous childbirth with a LBW infant. Approximately 27 % of women had more than one risk factor: depressed mood was significantly associated with alcohol use and LBW, with a trend to significance with HIV+. In addition, alcohol use was significantly related to HIV+. These results suggest the importance of intervening across multiple risks to maternal and child health, and particularly with depression and alcohol use, to positively impact multiple maternal and infant outcomes.

  14. Pre-operative factors indicating risk of multiple operations versus a single operation in women undergoing surgery for screen detected breast cancer.

    PubMed

    O'Flynn, E A M; Currie, R J; Mohammed, K; Allen, S D; Michell, M J

    2013-02-01

    We aim to identify preoperative factors at diagnosis which could predict whether women undergoing wide local excision (WLE) would require further operations. 1593 screen-detected invasive and non-invasive breast cancers were reviewed. Age, presence of ductal carcinoma in situ (DCIS), invasive cancer size on mammography, mammographic sign, tumour type, grade and confidence of the radiologist in malignancy were compared. 83%(1315/1593) of women had a WLE. Of these, 70%(919/1315) had a single operation, and 30%(396/1315) multiple operations. These included repeat WLE to clear margins (60%(238/396)), mastectomy (34%(133/396)) and axillary dissection (6%(25/396)). The presence of mammographic microcalcification, lobular carcinoma and grade 2 malignancy on core biopsy were independent risk factors for multiple operations on multivariate analysis. Women with mammographic DCIS >30 mm were 3.4 times more likely to undergo repeat surgery than those with smaller foci. The multidisciplinary team should pay particular attention to these factors when planning surgery. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Mutually unbiased product bases for multiple qudits

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

    McNulty, Daniel; Pammer, Bogdan; Weigert, Stefan

    We investigate the interplay between mutual unbiasedness and product bases for multiple qudits of possibly different dimensions. A product state of such a system is shown to be mutually unbiased to a product basis only if each of its factors is mutually unbiased to all the states which occur in the corresponding factors of the product basis. This result implies both a tight limit on the number of mutually unbiased product bases which the system can support and a complete classification of mutually unbiased product bases for multiple qubits or qutrits. In addition, only maximally entangled states can be mutuallymore » unbiased to a maximal set of mutually unbiased product bases.« less

  16. Construct validity and frequency of euphoria sclerotica in multiple sclerosis.

    PubMed

    Fishman, Inna; Benedict, Ralph H B; Bakshi, Rohit; Priore, Roger; Weinstock-Guttman, Bianca

    2004-01-01

    Using the Neuropsychiatric Inventory (NPI), we studied euphoria and other behavioral changes in 75 consecutive, unselected multiple sclerosis (MS) patients and 25 healthy controls. We also assessed disease duration, clinical course, physical disability, personality, depression, insight, cognition, and caregiver distress. Factor analysis identified a cluster of symptoms--labeled euphoria/disinhibition--similar to the euphoria sclerotica syndrome originally described by Charcot and others. The euphoria/disinhibition factor score was elevated in 9% of patients and associated with secondary-progressive course, low agreeableness, poor insight, impaired cognition, and high caregiver distress. Thus, we used the NPI to validate the euphoria syndrome in multiple sclerosis (MS) and determined its frequency, and its neurological and psychological correlates.

  17. The sigma factors of Bacillus subtilis.

    PubMed Central

    Haldenwang, W G

    1995-01-01

    The specificity of DNA-dependent RNA polymerase for target promotes is largely due to the replaceable sigma subunit that it carries. Multiple sigma proteins, each conferring a unique promoter preference on RNA polymerase, are likely to be present in all bacteria; however, their abundance and diversity have been best characterized in Bacillus subtilis, the bacterium in which multiple sigma factors were first discovered. The 10 sigma factors thus far identified in B. subtilis directly contribute to the bacterium's ability to control gene expression. These proteins are not merely necessary for the expression of those operons whose promoters they recognize; in many instances, their appearance within the cell is sufficient to activate these operons. This review describes the discovery of each of the known B. subtilis sigma factors, their characteristics, the regulons they direct, and the complex restrictions placed on their synthesis and activities. These controls include the anticipated transcriptional regulation that modulates the expression of the sigma factor structural genes but, in the case of several of the B. subtilis sigma factors, go beyond this, adding novel posttranslational restraints on sigma factor activity. Two of the sigma factors (sigma E and sigma K) are, for example, synthesized as inactive precursor proteins. Their activities are kept in check by "pro-protein" sequences which are cleaved from the precursor molecules in response to intercellular cues. Other sigma factors (sigma B, sigma F, and sigma G) are inhibited by "anti-sigma factor" proteins that sequester them into complexes which block their ability to form RNA polymerase holoenzymes. The anti-sigma factors are, in turn, opposed by additional proteins which participate in the sigma factors' release. The devices used to control sigma factor activity in B, subtilis may prove to be as widespread as multiple sigma factors themselves, providing ways of coupling sigma factor activation to environmental or physiological signals that cannot be readily joined to other regulatory mechanisms. PMID:7708009

  18. Monochorionic triplets after single embryo transfer.

    PubMed

    Rísquez, Francisco; Gil, Mónica; D'Ommar, Gustavo; Poo, María; Sosa, Anna; Piras, Marta

    2004-10-01

    A 40-year-old patient underwent intracytoplasmic sperm injection and assisted hatching, and a single embryo was transferred. Ultrasonography demonstrated a single gestational sac containing monochorionic tri-amniotic pregnancy. Several factors that have been implicated in the aetiology of monozygotic triple pregnancies after IVF appear to be present in this case. To avoid multiple pregnancies after IVF, it is time to have definite predictive factors for the occurrence of monozygotic multiple pregnancies as well as transferring only a single embryo.

  19. Patterns of evolution at the gametophytic self-incompatibility Sorbus aucuparia (Pyrinae) S pollen genes support the non-self recognition by multiple factors model.

    PubMed

    Aguiar, Bruno; Vieira, Jorge; Cunha, Ana E; Fonseca, Nuno A; Reboiro-Jato, David; Reboiro-Jato, Miguel; Fdez-Riverola, Florentino; Raspé, Olivier; Vieira, Cristina P

    2013-05-01

    S-RNase-based gametophytic self-incompatibility evolved once before the split of the Asteridae and Rosidae. In Prunus (tribe Amygdaloideae of Rosaceae), the self-incompatibility S-pollen is a single F-box gene that presents the expected evolutionary signatures. In Malus and Pyrus (subtribe Pyrinae of Rosaceae), however, clusters of F-box genes (called SFBBs) have been described that are expressed in pollen only and are linked to the S-RNase gene. Although polymorphic, SFBB genes present levels of diversity lower than those of the S-RNase gene. They have been suggested as putative S-pollen genes, in a system of non-self recognition by multiple factors. Subsets of allelic products of the different SFBB genes interact with non-self S-RNases, marking them for degradation, and allowing compatible pollinations. This study performed a detailed characterization of SFBB genes in Sorbus aucuparia (Pyrinae) to address three predictions of the non-self recognition by multiple factors model. As predicted, the number of SFBB genes was large to account for the many S-RNase specificities. Secondly, like the S-RNase gene, the SFBB genes were old. Thirdly, amino acids under positive selection-those that could be involved in specificity determination-were identified when intra-haplotype SFBB genes were analysed using codon models. Overall, the findings reported here support the non-self recognition by multiple factors model.

  20. Change in "resolved plans" and "suicidal ideation" factors of suicidality after participation in an intensive outpatient treatment program.

    PubMed

    Minnix, Jennifer A; Romero, Catherine; Joiner, Thomas E; Weinberg, Elizabeth F

    2007-11-01

    This study aims to investigate factors related to suicide in a unique clinical population with more chronic psychopathology than many outpatient samples. One hundred and five adult outpatients were included in the current study. We predicted that higher scores on the resolved plans and preparation (RPP) factor of the Beck Suicide Scale [Beck, A.T., Kovacs, M., Weissman, M., (1979). Assessment of suicidal intention: The scale for suicidal ideation. Journal of Consulting and Clinical Psychology 47, 343-352] would predict multiple attempter status even after accounting for co-morbid diagnoses and suicidal ideation (SI) factor scores. Additionally, we predicted that the scores on the RPP factor would decrease less over time than scores on the SI factor. Results were consistent with both hypotheses, suggesting that RPP factor scores were uniquely predictive of status as a multiple attempter and were more stable over time. Mental health diagnoses were rendered without the use of a structured interview and therefore no reliability data were collected.

  1. Biomaterial delivery of morphogens to mimic the natural healing cascade in bone

    PubMed Central

    Mehta, Manav; Schmidt-Bleek, Katharina; Duda, Georg N; Mooney, David J

    2012-01-01

    Complications in treatment of large bone defects using bone grafting still remain. Our understanding of the endogenous bone regeneration cascade has inspired the exploration of a wide variety of growth factors (GFs) in an effort to mimic the natural signaling that controls bone healing. Biomaterial-based delivery of single exogenous GFs has shown therapeutic efficacy, and this likely relates to its ability to recruit and promote replication of cells involved in tissue development and the healing process. However, as the natural bone healing cascade involves the action of multiple factors, each acting in a specific spatiotemporal pattern, strategies aiming to mimic the critical aspects of this process will likely benefit from the usage of multiple therapeutic agents. This article reviews the current status of approaches to deliver single GFs, as well as ongoing efforts to develop sophisticated delivery platforms to deliver multiple lineage-directing morphogens (multiple GFs) during bone healing. PMID:22626978

  2. Physics of cardiac imaging with multiple-row detector CT.

    PubMed

    Mahesh, Mahadevappa; Cody, Dianna D

    2007-01-01

    Cardiac imaging with multiple-row detector computed tomography (CT) has become possible due to rapid advances in CT technologies. Images with high temporal and spatial resolution can be obtained with multiple-row detector CT scanners; however, the radiation dose associated with cardiac imaging is high. Understanding the physics of cardiac imaging with multiple-row detector CT scanners allows optimization of cardiac CT protocols in terms of image quality and radiation dose. Knowledge of the trade-offs between various scan parameters that affect image quality--such as temporal resolution, spatial resolution, and pitch--is the key to optimized cardiac CT protocols, which can minimize the radiation risks associated with these studies. Factors affecting temporal resolution include gantry rotation time, acquisition mode, and reconstruction method; factors affecting spatial resolution include detector size and reconstruction interval. Cardiac CT has the potential to become a reliable tool for noninvasive diagnosis and prevention of cardiac and coronary artery disease. (c) RSNA, 2007.

  3. Temporally controlled release of multiple growth factors from a self-assembling peptide hydrogel

    NASA Astrophysics Data System (ADS)

    Bruggeman, Kiara F.; Rodriguez, Alexandra L.; Parish, Clare L.; Williams, Richard J.; Nisbet, David R.

    2016-09-01

    Protein growth factors have demonstrated great potential for tissue repair, but their inherent instability and large size prevents meaningful presentation to biologically protected nervous tissue. Here, we create a nanofibrous network from a self-assembling peptide (SAP) hydrogel to carry and stabilize the growth factors. We significantly reduced growth factor degradation to increase their lifespan by over 40 times. To control the temporal release profile we covalently attached polysaccharide chitosan molecules to the growth factor to increase its interactions with the hydrogel nanofibers and achieved a 4 h delay, demonstrating the potential of this method to provide temporally controlled growth factor delivery. We also describe release rate based analysis to examine the growth factor delivery in more detail than standard cumulative release profiles allow and show that the chitosan attachment method provided a more consistent release profile with a 60% reduction in fluctuations. To prove the potential of this system as a complex growth factor delivery platform we demonstrate for the first time temporally distinct release of multiple growth factors from a single tissue specific SAP hydrogel: a significant goal in regenerative medicine.

  4. A Factor Analytic Model of Drug-Related Behavior in Adolescence and Its Impact on Arrests at Multiple Stages of the Life Course

    PubMed Central

    2016-01-01

    Objectives Recognizing the inherent variability of drug-related behaviors, this study develops an empirically-driven and holistic model of drug-related behavior during adolescence using factor analysis to simultaneously model multiple drug behaviors. Methods The factor analytic model uncovers latent dimensions of drug-related behaviors, rather than patterns of individuals. These latent dimensions are treated as empirical typologies which are then used to predict an individual’s number of arrests accrued at multiple phases of the life course. The data are robust enough to simultaneously capture drug behavior measures typically considered in isolation in the literature, and to allow for behavior to change and evolve over the period of adolescence. Results Results show that factor analysis is capable of developing highly descriptive patterns of drug offending, and that these patterns have great utility in predicting arrests. Results further demonstrate that while drug behavior patterns are predictive of arrests at the end of adolescence for both males and females, the impacts on arrests are longer lasting for females. Conclusions The various facets of drug behaviors have been a long-time concern of criminological research. However, the ability to model multiple behaviors simultaneously is often constrained by data that do not measure the constructs fully. Factor analysis is shown to be a useful technique for modeling adolescent drug involvement patterns in a way that accounts for the multitude and variability of possible behaviors, and in predicting future negative life outcomes, such as arrests. PMID:28435183

  5. A mammary cell-specific enhancer in mouse mammary tumor virus DNA is composed of multiple regulatory elements including binding sites for CTF/NFI and a novel transcription factor, mammary cell-activating factor.

    PubMed Central

    Mink, S; Härtig, E; Jennewein, P; Doppler, W; Cato, A C

    1992-01-01

    Mouse mammary tumor virus (MMTV) is a milk-transmitted retrovirus involved in the neoplastic transformation of mouse mammary gland cells. The expression of this virus is regulated by mammary cell type-specific factors, steroid hormones, and polypeptide growth factors. Sequences for mammary cell-specific expression are located in an enhancer element in the extreme 5' end of the long terminal repeat region of this virus. This enhancer, when cloned in front of the herpes simplex thymidine kinase promoter, endows the promoter with mammary cell-specific response. Using functional and DNA-protein-binding studies with constructs mutated in the MMTV long terminal repeat enhancer, we have identified two main regulatory elements necessary for the mammary cell-specific response. These elements consist of binding sites for a transcription factor in the family of CTF/NFI proteins and the transcription factor mammary cell-activating factor (MAF) that recognizes the sequence G Pu Pu G C/G A A G G/T. Combinations of CTF/NFI- and MAF-binding sites or multiple copies of either one of these binding sites but not solitary binding sites mediate mammary cell-specific expression. The functional activities of these two regulatory elements are enhanced by another factor that binds to the core sequence ACAAAG. Interdigitated binding sites for CTF/NFI, MAF, and/or the ACAAAG factor are also found in the 5' upstream regions of genes encoding whey milk proteins from different species. These findings suggest that mammary cell-specific regulation is achieved by a concerted action of factors binding to multiple regulatory sites. Images PMID:1328867

  6. Neonatal Risk Factors for Treatment-Demanding Retinopathy of Prematurity: A Danish National Study.

    PubMed

    Slidsborg, Carina; Jensen, Aksel; Forman, Julie Lyng; Rasmussen, Steen; Bangsgaard, Regitze; Fledelius, Hans Callø; Greisen, Gorm; la Cour, Morten

    2016-04-01

    One goal of the study was to identify "new" statistically independent risk factors for treatment-demanding retinopathy of prematurity (ROP). Another goal was to evaluate whether any new risk factors could explain the increase in the incidence of treatment-demanding ROP over time in Denmark. A retrospective, register-based cohort study. The study included premature infants (n = 6490) born in Denmark from 1997 to 2008. The study sample and the 31 candidate risk factors were identified in 3 national registers. Data were linked through a unique civil registration number. Each of the 31 candidate risk factors were evaluated in univariate analyses, while adjusted for known risk factors (i.e., gestational age [GA] at delivery, small for gestational age [SGA], multiple births, and male sex). Significant outcomes were analyzed thereafter in a backward selection multiple logistic regression model. Treatment-demanding ROP and its associations to candidate risk factors. Mechanical ventilation (odds ratio [OR], 2.84; 95% confidence interval [CI], 1.99-4.08; P < 0.01) and blood transfusion (OR, 1.97; 95% CI, 1.20-3.14; P = 0.01) were the only new statistically independent risk factors, in addition to GA at delivery, SGA, multiple births, and male sex. Modification in these prognostic factors for ROP did not cause an increase in treatment-demanding ROP. In a large study population, blood transfusion and mechanical ventilation were the only new statistically independent risk factors to predict the development of treatment-demanding ROP. Modification in the neonatal treatment with mechanical ventilation or blood transfusion did not cause the observed increase in the incidence of preterm infants with treatment-demanding ROP during a recent birth period (2003-2008). Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  7. Antecedents of Coping with the Disease in Patients with Multiple Sclerosis: A Qualitative Content Analysis

    PubMed Central

    Dehghani, Ali; Dehghan Nayeri, Nahid; Ebadi, Abbas

    2017-01-01

    ABSTRACT Background: Due to many physical and mental disorders that occur in multiple sclerosis patients, identifying the factors affecting coping based on the experiences of patients using qualitative study is essential to improve their quality of life. This study was conducted to explore the antecedents of coping with the disease in patients with multiple sclerosis. Methods: This is a qualitative study conducted on 11 patients with multiple sclerosis in 2015 in Tehran, Iran. These patients were selected based on purposive sampling. Data were collected using semi-structured and in-depth interviews and coded. These data were analyzed using the conventional content analysis. The rigor of qualitative data using the criteria proposed by Guba and Lincoln were assessed. Results: Five main categories were revealed: (1) social support, (2) lenience, (3) reliance on faith, (4) knowledge of multiple sclerosis and modeling, and (5) economic and environmental situation. Each category had several distinct sub-categories. Conclusions: The results of this study showed that coping with multiple sclerosis is a complex, multidimensional and contextual concept that is affected by various factors in relation to the context of Iran. The findings of the study can provide the healthcare professionals with deeper recognition and understanding of these antecedents to improve successful coping in Iranian patients suffering from multiple sclerosis. PMID:28097178

  8. Methods for Improving Information from ’Undesigned’ Human Factors Experiments.

    DTIC Science & Technology

    Human factors engineering, Information processing, Regression analysis , Experimental design, Least squares method, Analysis of variance, Correlation techniques, Matrices(Mathematics), Multiple disciplines, Mathematical prediction

  9. How agricultural multiple ecosystem services respond to socioeconomic factors in Mengyin County, China.

    PubMed

    Chen, Yajuan; Yu, Zhenrong; Li, Xuedong; Li, Pengyao

    2018-07-15

    Provisioning services have always been the main focus of agriculture, and which have led to a decline in biodiversity and have damaged a number of other services. Agriculture should contribute to current and future food security while producing multiple ecosystem services (ES). Restoration outcomes of multiple ES were affected by different socioeconomic drivers, thus a better understanding of how multiple ES respond to socioeconomic drivers can help to restore multiple ES. This paper used rural people's perceptions of ES to quantify and map ecosystem service obtainment and demand in the Mengyin County, China. An integrative index of multiple ecosystem services (IMES) was used to effectively aggregate the values of multiple ES. The threat categorization framework is designed to communicate the degree to which the adequate and sustainable provision of multiple ES is threatened, in order to prioritize conservation actions. The results revealed that 6 townships in the Mengyin County exhibited an excessive obtainment situation (demand is less than obtainment) of multiple ES; an insufficient obtainment situation (demand is greater than obtainment) of multiple ES was mainly situated in the northern part of Mengyin County. Overall, the current state of multiple ES across Mengyin County is classified as "Endangered" classification according to application of threat categorization framework. It is necessary to restructure and manage socioeconomic factors for multiple ES. At national level, the macro decision-making (controlling population density) and the mechanisms (attracting high-quality human resources into the rural) will play an important role in promoting multiple ES management, and it is necessary to provide 3 or more years of tailored educational resources for rural residents to advance multiple ES in agricultural landscape. Development of agricultural PES programs in China that enable farmers to profit from production ES is a sustainable strategy for increasing multiple ecosystem services. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Exploratory and Higher-Order Factor Analyses of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) Adolescent Subsample

    ERIC Educational Resources Information Center

    Canivez, Gary L.; Watkins, Marley W.

    2010-01-01

    The factor structure of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV; Wechsler, 2008a) with the adolescent participants (ages 16-19 years; N = 400) in the standardization sample was assessed using exploratory factor analysis, multiple factor extraction criteria, and higher-order exploratory factor analyses. Results from…

  11. Outlet strut fracture of Björk-Shiley convexo-concave valves: can valve-manufacturing characteristics explain the risk?

    PubMed

    Omar, R Z; Morton, L S; Beirne, M; Blot, W J; Lawford, P V; Hose, R; Taylor, K M

    2001-06-01

    Björk-Shiley 60 degrees convexo-concave prosthetic heart valves (Shiley, Inc, Irvine, Calif, a subsidiary of Pfizer, Inc) continue to be a concern for approximately 35,000 nonexplanted patients worldwide, with approximately 600 events reported to the manufacturer to date. Fractures of the outlet struts of the valves began to appear in the early 1980s and have continued to the present, but their causes are only partially understood. A matched case-control study was conducted evaluating manufacturing records for 52 valves with outlet strut fractures and 248 control subjects matched for age at implantation, valve size, and valve position. In addition to the risk factors recognized as determinants of outlet strut fracture, the United Kingdom case-control study has observed 7- to 9-fold increased risk with performance of multiple hook deflection tests. This test was performed more than once, usually after rework on the valve. Six valves in this study underwent multiple hook deflection tests, of which 4 experienced an outlet strut fracture. Cracks and further rework were noted for these valves. Significant associations were also observed between outlet strut fracture and disc-to-strut gap measurements taken before the attachment of the sewing ring. It is our view that a combination of factors related to valve design, manufacturing process, and patient characteristics are responsible for outlet strut fractures of Björk-Shiley convexo-concave valves. Multiple hook deflection tests have emerged as a potential new risk factor for outlet strut fracture in both The Netherlands and the United Kingdom. This factor appears to be correlated with the presence of other abnormalities. A further study is needed to investigate the factors correlated with multiple hook deflection tests. On confirmation of risk, the presence of multiple hook deflection tests may be added to equations, quantifying the risk of outlet strut fracture for comparison against risk of mortality and serious morbidity from explant operations.

  12. The extraction of simple relationships in growth factor-specific multiple-input and multiple-output systems in cell-fate decisions by backward elimination PLS regression.

    PubMed

    Akimoto, Yuki; Yugi, Katsuyuki; Uda, Shinsuke; Kudo, Takamasa; Komori, Yasunori; Kubota, Hiroyuki; Kuroda, Shinya

    2013-01-01

    Cells use common signaling molecules for the selective control of downstream gene expression and cell-fate decisions. The relationship between signaling molecules and downstream gene expression and cellular phenotypes is a multiple-input and multiple-output (MIMO) system and is difficult to understand due to its complexity. For example, it has been reported that, in PC12 cells, different types of growth factors activate MAP kinases (MAPKs) including ERK, JNK, and p38, and CREB, for selective protein expression of immediate early genes (IEGs) such as c-FOS, c-JUN, EGR1, JUNB, and FOSB, leading to cell differentiation, proliferation and cell death; however, how multiple-inputs such as MAPKs and CREB regulate multiple-outputs such as expression of the IEGs and cellular phenotypes remains unclear. To address this issue, we employed a statistical method called partial least squares (PLS) regression, which involves a reduction of the dimensionality of the inputs and outputs into latent variables and a linear regression between these latent variables. We measured 1,200 data points for MAPKs and CREB as the inputs and 1,900 data points for IEGs and cellular phenotypes as the outputs, and we constructed the PLS model from these data. The PLS model highlighted the complexity of the MIMO system and growth factor-specific input-output relationships of cell-fate decisions in PC12 cells. Furthermore, to reduce the complexity, we applied a backward elimination method to the PLS regression, in which 60 input variables were reduced to 5 variables, including the phosphorylation of ERK at 10 min, CREB at 5 min and 60 min, AKT at 5 min and JNK at 30 min. The simple PLS model with only 5 input variables demonstrated a predictive ability comparable to that of the full PLS model. The 5 input variables effectively extracted the growth factor-specific simple relationships within the MIMO system in cell-fate decisions in PC12 cells.

  13. Multi-Population Invariance with Dichotomous Measures: Combining Multi-Group and MIMIC Methodologies in Evaluating the General Aptitude Test in the Arabic Language

    ERIC Educational Resources Information Center

    Sideridis, Georgios D.; Tsaousis, Ioannis; Al-harbi, Khaleel A.

    2015-01-01

    The purpose of the present study was to extend the model of measurement invariance by simultaneously estimating invariance across multiple populations in the dichotomous instrument case using multi-group confirmatory factor analytic and multiple indicator multiple causes (MIMIC) methodologies. Using the Arabic version of the General Aptitude Test…

  14. Applying a Multiple Group Causal Indicator Modeling Framework to the Reading Comprehension Skills of Third, Seventh, and Tenth Grade Students

    ERIC Educational Resources Information Center

    Tighe, Elizabeth L.; Wagner, Richard K.; Schatschneider, Christopher

    2015-01-01

    This study demonstrates the utility of applying a causal indicator modeling framework to investigate important predictors of reading comprehension in third, seventh, and tenth grade students. The results indicated that a 4-factor multiple indicator multiple indicator cause (MIMIC) model of reading comprehension provided adequate fit at each grade…

  15. Multiple Risks, Emotion Regulation Skill, and Cortisol in Low-Income African American Youth: A Prospective Study

    ERIC Educational Resources Information Center

    Kliewer, Wendy; Reid-Quinones, Kathryn; Shields, Brian J.; Foutz, Lauren

    2009-01-01

    Associations between multiple risks, emotion regulation skill, and basal cortisol levels were examined in a community sample of 69 African American youth (mean age = 11.30 years; 49% male) living in an urban setting. Multiple risks were assessed at Time 1 and consisted of 10 demographic and psychosocial risk factors including parent, child, and…

  16. Factors Affecting Student Burnout and Academic Achievement in Multiple Enrollment Programs in Taiwan's Technical-Vocational Colleges

    ERIC Educational Resources Information Center

    Yang, Hui-Jen

    2004-01-01

    Instead of the 44-year joint entrance examination held so far in Taiwan, multiple enrollment programs are a more recent policy of the Ministry of Education to reform the deficiencies of the above mentioned examination. However, the results of multiple enrollment programs in reducing student pressure are not clear. Therefore, the main purpose of…

  17. Leading Schools in Circumstances of Multiple Deprivation in South Africa: Mapping Some Conceptual, Contextual and Research Dimensions

    ERIC Educational Resources Information Center

    Maringe, Felix; Moletsane, Relebohile

    2015-01-01

    The paper suggests that multiple deprivation is a concept as yet lacking in substantial theoretical analysis and that its application as a research framing tool in education is relatively recent. As a concept, multiple deprivation suggests a confluence of factors which depress learning and place unique challenges on leadership and which act in…

  18. Improving medical records filing in a municipal hospital in Ghana.

    PubMed

    Teviu, E A A; Aikins, M; Abdulai, T I; Sackey, S; Boni, P; Afari, E; Wurapa, F

    2012-09-01

    Medical records are kept in the interest of both the patient and clinician. Proper filing of patient's medical records ensures easy retrieval and contributes to decreased patient waiting time at the hospital and continuity of care. This paper reports on an intervention study to address the issue of misfiling and multiple patient folders in a health facility. Intervention study. Municipal Hospital, Goaso, Asunafo North District, Brong Ahafo Region, Ghana. Methods employed for data collection were records review, direct observation and tracking of folders. Interventions instituted were staff durbars, advocacy and communication, consultations, in-service trainings, procurement and monitoring. Factors contributing to issuance of multiple folders and misfiling were determined. Proportion of multiple folders was estimated. Results revealed direct and indirect factors contributing to issuance of multiple patient folders and misfiling. Interventions and monitoring reduce acquisition of numerous medical folders per patient and misfiling. After the intervention, there was significant reduction in the use of multiple folders (i.e., overall 97% reduction) and a high usage of single patient medical folders (i.e., 99%). In conclusion, a defined medical records filing system with adequate training, logistics and regular monitoring and supervision minimises issuance of multiple folders and misfiling.

  19. Electric properties and carrier multiplication in breakdown sites in multi-crystalline silicon solar cells

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

    Schneemann, Matthias; Carius, Reinhard; Rau, Uwe

    2015-05-28

    This paper studies the effective electrical size and carrier multiplication of breakdown sites in multi-crystalline silicon solar cells. The local series resistance limits the current of each breakdown site and is thereby linearizing the current-voltage characteristic. This fact allows the estimation of the effective electrical diameters to be as low as 100 nm. Using a laser beam induced current (LBIC) measurement with a high spatial resolution, we find carrier multiplication factors on the order of 30 (Zener-type breakdown) and 100 (avalanche breakdown) as new lower limits. Hence, we prove that also the so-called Zener-type breakdown is followed by avalanche multiplication. Wemore » explain that previous measurements of the carrier multiplication using thermography yield results higher than unity, only if the spatial defect density is high enough, and the illumination intensity is lower than what was used for the LBIC method. The individual series resistances of the breakdown sites limit the current through these breakdown sites. Therefore, the measured multiplication factors depend on the applied voltage as well as on the injected photocurrent. Both dependencies are successfully simulated using a series-resistance-limited diode model.« less

  20. Number of Sexual Partners and Relationship Status Are Associated With Unprotected Sex Across Emerging Adulthood

    PubMed Central

    Wilhite, Emily R.; Harden, K. Paige; Fromme, Kim

    2018-01-01

    Sex with multiple partners, consecutively or concurrently, is a risk factor for contracting sexually transmitted infections (STIs) as multiple partner–partner contacts present increased opportunity for transmission. It is unclear, however, if individuals who tend to have more partners also use protection less reliably than those with sexual histories of fewer partners. Longitudinal data can elucidate whether an individual shows a consistent pattern of sex with multiple partners. We used latent class growth analyses to examine emerging adult survey data (N = 2244) spanning 10 waves of assessment across 6 years. We identified three trajectory classes described with respect to number of partners as (a) Multiple, (b) Single, and (c) Rare. Trajectory group, relationship status, and their interactions were tested as predictors of using protection against STIs and pregnancy at each wave. The Multiple Partners class had the greatest odds ratio of reporting sex without protection against STIs and pregnancy, followed by the Single and Rare classes. Exclusive relationship status was a risk factor for unprotected sex at earlier waves, but a protective factor at most later waves. There was no significant interaction between relationship status and trajectory class in predicting use of protection. The Multiple Partners class reported more permissive values on sex and an elevated proportion of homosexual behavior. This group overlaps with an already identified at-risk population, men who have sex with men. Potential mechanisms explaining the increased risk for sex without protection, including communication, risk assessment, and co-occurring risk behaviors are discussed as targets for intervention. PMID:26940966

  1. Number of Sexual Partners and Relationship Status Are Associated With Unprotected Sex Across Emerging Adulthood.

    PubMed

    Ashenhurst, James R; Wilhite, Emily R; Harden, K Paige; Fromme, Kim

    2017-02-01

    Sex with multiple partners, consecutively or concurrently, is a risk factor for contracting sexually transmitted infections (STIs) as multiple partner-partner contacts present increased opportunity for transmission. It is unclear, however, if individuals who tend to have more partners also use protection less reliably than those with sexual histories of fewer partners. Longitudinal data can elucidate whether an individual shows a consistent pattern of sex with multiple partners. We used latent class growth analyses to examine emerging adult survey data (N = 2244) spanning 10 waves of assessment across 6 years. We identified three trajectory classes described with respect to number of partners as (a) Multiple, (b) Single, and (c) Rare. Trajectory group, relationship status, and their interactions were tested as predictors of using protection against STIs and pregnancy at each wave. The Multiple Partners class had the greatest odds ratio of reporting sex without protection against STIs and pregnancy, followed by the Single and Rare classes. Exclusive relationship status was a risk factor for unprotected sex at earlier waves, but a protective factor at most later waves. There was no significant interaction between relationship status and trajectory class in predicting use of protection. The Multiple Partners class reported more permissive values on sex and an elevated proportion of homosexual behavior. This group overlaps with an already identified at-risk population, men who have sex with men. Potential mechanisms explaining the increased risk for sex without protection, including communication, risk assessment, and co-occurring risk behaviors are discussed as targets for intervention.

  2. Coexistence of multiple sclerosis and ankylosing spondylitis: Report of four cases from Russia and review of the literature.

    PubMed

    Fominykh, Vera; Shevtsova, Tatyana; Arzumanian, Narine; Brylev, Lev

    2017-10-01

    Multiple sclerosis is a chronic demyelinating disorder of the central nervous system. There are many cases of multiple sclerosis - like syndrome and demyelinating disorders in systemic lupus erythematosus, Sjogren disease, Behcet disease and other autoimmune conditions. Coexistence of ankylosing spondylitis and multiple sclerosis usually is rare but in this article we report 4 Russian patients with concomitant multiple sclerosis and ankylosing spondylitis diseases. None of these patients received anti-tumor necrosis factor alpha therapy prior to diagnosis of multiple sclerosis. Pathogenesis, diagnostic and treatment challenges are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. The association of reproductive and lifestyle factors with a score of multiple endogenous hormones

    PubMed Central

    Shafrir, Amy L.; Zhang, Xuehong; Poole, Elizabeth M.; Hankinson, Susan E.; Tworoger, Shelley S.

    2014-01-01

    Introduction We recently reported that high levels of multiple sex and growth hormones were associated with increased postmenopausal breast cancer risk. Limited research has explored the relationship between reproductive, anthropometric, and lifestyle factors and levels of multiple hormones simultaneously. Methods This cross-sectional analysis included 738 postmenopausal Nurses' Health Study participants who were controls in a breast cancer nested case-control study and had measured levels of estrone, estradiol, estrone sulfate, testosterone, androstenedione, dehydroepiandrosterone sulfate, prolactin and sex hormone binding globulin (SHBG). A score was created by summing the number of hormones a woman had above (below for SHBG) each hormone's age-adjusted geometric mean. The association between lifestyle, anthropometric, and reproductive exposures and the score was assessed using generalized linear models. Results The hormone score ranged from 0 to 8 with a mean of 4.0 (standard deviation=2.2). Body mass index (BMI) and alcohol consumption at blood draw were positively associated with the hormone score: a 5 unit increase in BMI was associated with a 0.79 (95%CI: 0.63, 0.95) unit increase in the score (p<0.0001) and each 15 grams/day increase in alcohol consumption was associated with a 0.41 (95%CI: 0.18, 0.63) unit increase in the score (p=0.0004). Family history of breast cancer, age at menarche, and physical activity were not associated with the score. Conclusions Reproductive breast cancer risk factors were not associated with elevated levels of multiple endogenous hormones, whereas anthropometric and lifestyle factors, particularly BMI and alcohol consumption, tended to be associated with higher levels of multiple hormones. PMID:25048255

  4. The association of reproductive and lifestyle factors with a score of multiple endogenous hormones.

    PubMed

    Shafrir, Amy L; Zhang, Xuehong; Poole, Elizabeth M; Hankinson, Susan E; Tworoger, Shelley S

    2014-10-01

    We recently reported that high levels of multiple sex and growth hormones were associated with increased postmenopausal breast cancer risk. Limited research has explored the relationship between reproductive, anthropometric, and lifestyle factors and levels of multiple hormones simultaneously. This cross-sectional analysis included 738 postmenopausal Nurses' Health Study participants who were controls in a breast cancer nested case-control study and had measured levels of estrone, estradiol, estrone sulfate, testosterone, androstenedione, dehydroepiandrosterone sulfate, prolactin, and sex hormone binding globulin (SHBG). A score was created by summing the number of hormones a woman had above (below for SHBG) each hormone's age-adjusted geometric mean. The association between lifestyle, anthropometric, and reproductive exposures and the score was assessed using generalized linear models. The hormone score ranged from 0 to 8 with a mean of 4.0 (standard deviation = 2.2). Body mass index (BMI) and alcohol consumption at blood draw were positively associated with the hormone score: a 5 unit increase in BMI was associated with a 0.79 (95%CI: 0.63, 0.95) unit increase in the score (p < 0.0001) and each 15 g/day increase in alcohol consumption was associated with a 0.41 (95%CI: 0.18, 0.63) unit increase in the score (p = 0.0004). Family history of breast cancer, age at menarche, and physical activity were not associated with the score. Reproductive breast cancer risk factors were not associated with elevated levels of multiple endogenous hormones, whereas anthropometric and lifestyle factors, particularly BMI and alcohol consumption, tended to be associated with higher levels of multiple hormones.

  5. Environmental conditions and reproductive health outcomes

    EPA Science Inventory

    Environmental exposures range across multiple domains to affect human health. In an effort to learn how environmental factors combine to contribute to health outcomes we constructed a multiple environmental domain index (MEDI) for use in health research. We used principal compone...

  6. Myeloproliferative neoplasms in five multiple sclerosis patients☆

    PubMed Central

    Thorsteinsdottir, Sigrun; Bjerrum, Ole Weis; Hasselbalch, Hans Carl

    2013-01-01

    The concurrence of myeloproliferative neoplasms (MPNs) and multiple sclerosis (MS) is unusual. We report five patients from a localized geographic area in Denmark with both MS and MPN; all the patients were diagnosed with MPNs in the years 2007–2012. We describe the patients' history and treatment. A potential link between MS and MPNs has not been previously recognized. This observation calls attention to potential environmental factors and/or previously unrecognized genetic factors predisposing these patients to both MS and MPNs. PMID:24371783

  7. Factors Associated with Falls in Community-Dwelling Older People with Focus on Participation in Sport Organizations: The Japan Gerontological Evaluation Study Project

    PubMed Central

    Hayashi, Takahiro; Kondo, Katsunori; Suzuki, Kayo; Yamada, Minoru; Matsumoto, Daisuke

    2014-01-01

    Objective. Promoting participation in sport organizations may be a population strategy for preventing falls in older people. In this study, we examined whether participation in sport organizations is associated with fewer falls in older people even after adjusting for multiple individual and environmental factors. Methods. We used the Japan Gerontological Evaluation Study data of 90,610 people (31 municipalities) who were not eligible for public long-term care. Logistic regression analysis was performed, with multiple falls over the past year as the dependent variable and participation in a sport organization as the independent variable, controlling for 13 factors. These included individual factors related to falls, such as age and sex, and environmental factors such as population density of the habitable area. Results. A total of 6,391 subjects (7.1%) had a history of multiple falls. Despite controlling for 13 variables, those who participated in a sport organization at least once a week were approximately ≥20% less likely to fall than those who did not participate at all (once a week; odds ratio = 0.82 and 95% confidence interval = 0.72–0.95). Conclusion. Participation in a sport organization at least once per week might help prevent falls in the community-dwelling older people. PMID:24955360

  8. Suicidal ideation, risk factors, and communication with parents. An HBSC study on school children in Estonia, Lithuania, and Luxembourg.

    PubMed

    Mark, Lauraliisa; Samm, Algi; Tooding, Liina-Mai; Sisask, Merike; Aasvee, Katrin; Zaborskis, Apolinaras; Zemaitiene, Nida; Värnik, Airi

    2013-01-01

    Suicide is a leading cause of death among youth. In the year 2002, Lithuania had the 2nd, Luxembourg the 5th, and Estonia the 9th highest suicide rates among 15- to 19-year-olds across 90 countries worldwide. Suicidal ideation is a significant precursor to suicide. To report on the prevalence of and associations between suicidal ideation, smoking, alcohol consumption, physical fighting, bullying, and communication with parents among 15-year-old schoolchildren. The survey analyzes data from the 2005/2006 HBSC study from Estonia, Lithuania, and Luxembourg (N = 4,954). The risk factors were calculated through multinomial logistic regression analyses. The overall prevalence of suicidal ideation in the preceding year was 17%. Suicidal thoughts were associated with communication difficulties with parents (OR from 2.0 to 4.6) and other risk factors, especially multiple risks (OR for 4-5 concurrent risk factors from 4.5 to 13.6). Parent-child communication had a significant mediating effect by decreasing the odds for suicidality and multiple risks. The prevalence estimates were obtained by self-reports. The causal relationships need further investigation. The risk factors studied, particularly multiple risks, were associated with higher odds for suicidal ideation. Good parent-child communication is a significant resource for decreasing suicidal ideation among adolescents.

  9. Associations between Distal Upper Extremity Job Physical Factors and Psychosocial Measures in a Pooled Study

    PubMed Central

    2015-01-01

    Introduction. There is an increasing body of literature relating musculoskeletal diseases to both job physical exposures and psychosocial outcomes. Relationships between job physical exposure measures and psychosocial factors have not been well examined or quantified. These exploratory analyses evaluate relationships between quantified exposures and psychosocial outcomes. Methods. Individualized quantification of duration, repetition, and force and composite scores of the Strain Index (SI) and the Threshold Limit Value for Hand Activity Level (TLV for HAL) were compared to 10 psychosocial measures. Relationships and predicted probabilities were assessed using ordered logistic regression. Analyses were adjusted for age, BMI, and gender. Results and Discussion. Among 1834 study participants there were multiple statistically significant relationships. In general, as duration, repetition, and force increased, psychosocial factors worsened. However, general health and mental exhaustion improved with increasing job exposures. Depression was most strongly associated with increased repetition, while physical exhaustion was most strongly associated with increased force. SI and TLV for HAL were significantly related to multiple psychosocial factors. These relationships persisted after adjustment for strong confounders. Conclusion. This study quantified multiple associations between job physical exposures and occupational and nonoccupational psychosocial factors. Further research is needed to quantify the impacts on occupational health outcomes. PMID:26557686

  10. The carboxyl-terminus directs TAF(I)48 to the nucleus and nucleolus and associates with multiple nuclear import receptors.

    PubMed

    Dynes, Joseph L; Xu, Shuping; Bothner, Sarah; Lahti, Jill M; Hori, Roderick T

    2004-03-01

    The protein complex Selectivity Factor 1, composed of TBP, TAF(I)48, TAF(I)63 and TAF(I)110, is required for rRNA transcription by RNA polymerase I in the nucleolus. The steps involved in targeting Selectivity Factor 1 will be dependent on the transport pathways that are used and the localization signals that direct this trafficking. In order to investigate these issues, we characterized human TAF(I)48, a subunit of Selectivity Factor 1. By domain analysis of TAF(I)48, the carboxyl-terminal 51 residues were found to be required for the localization of TAF(I)48, as well as sufficient to direct Green Fluorescent Protein to the nucleus and nucleolus. The carboxyl-terminus of TAF(I)48 also has the ability to associate with multiple members of the beta-karyopherin family of nuclear import receptors, including importin beta (karyopherin beta1), transportin (karyopherin beta2) and RanBP5 (karyopherin beta3), in a Ran-dependent manner. This property of interacting with multiple beta-karyopherins has been previously reported for the nuclear localization signals of some ribosomal proteins that are likewise directed to the nucleolus. This study identifies the first nuclear import sequence identified within the TBP-Associated Factor subunits of Selectivity Factor 1.

  11. [Factors of psychiatric treatment satisfaction in inpatients with neurotic and depressive disorders].

    PubMed

    Tsygankov, B D; Malygin, Ya V; Gatin, F F

    2015-01-01

    Factors of patients' satisfaction with medical care vary depending on the level of care and medical specialty. Patient's satisfaction with psychiatric care is understudied. An aim of the present study is to find out the factors of satisfaction with psychiatric care in inpatients with neurotic and depressive disorders. The sample included 356 inpatients suffering from neurotic or depressive disorders. The patients were questioned using PAPI questionnaire designed for this study. Statistical analysis was performed using multiple regression. Key factors of satisfaction with medical care included quality of work of nurses and psychiatrists, hospital ward comfort, the number and quality of psychotherapeutic sessions, psychiatrists' empathy and aptitude to provide the patient with information about the disease and treatment. Multiple regression equation explained 81% of the variance of patients' satisfaction.

  12. Factors influencing health information system adoption in American hospitals.

    PubMed

    Wang, Bill B; Wan, Thomas T H; Burke, Darrell E; Bazzoli, Gloria J; Lin, Blossom Y J

    2005-01-01

    To study the number of health information systems (HISs), applicable to administrative, clinical, and executive decision support functionalities, adopted by acute care hospitals and to examine how hospital market, organizational, and financial factors influence HIS adoption. A cross-sectional analysis was performed with 1441 hospitals selected from metropolitan statistical areas in the United States. Multiple data sources were merged. Six hypotheses were empirically tested by multiple regression analysis. HIS adoption was influenced by the hospital market, organizational, and financial factors. Larger, system-affiliated, and for-profit hospitals with more preferred provider organization contracts are more likely to adopt managerial information systems than their counterparts. Operating revenue is positively associated with HIS adoption. The study concludes that hospital organizational and financial factors influence on hospitals' strategic adoption of clinical, administrative, and managerial information systems.

  13. FACTORS ADVERSELY AFFECTING AMPHIBIAN POPULATIONS IN THE US

    EPA Science Inventory

    Factors known or suspected to be adversely affecting native amphibian populations in the US were identified using information from species accounts written in a standardized format by multiple authors in a forthcoming book. Specific adverse factors were identified for 53 (58%) of...

  14. On the evaluation of air mass factors for atmospheric near-ultraviolet and visible absorption spectroscopy

    NASA Technical Reports Server (NTRS)

    Perliski, Lori M.; Solomon, Susan

    1993-01-01

    The interpretation of UV-visible twilight absorption measurements of atmospheric chemical constituents is dependent on how well the optical path, or air mass factor, of light collected by the spectrometer is understood. A simple single scattering model and a Monte Carlo radiative transfer scheme have been developed to study the effects of multiple scattering, aerosol scattering, surface albedo and refraction on air mass factors for scattered light observations. At fairly short visible wavelengths (less than about 450 nm), stratospheric air mass factors are found to be relatively insensitive to multiple scattering, surface albedo and refraction, as well as aerosol scattering by background aerosols. Longer wavelengths display greater sensitivity to refraction and aerosol scattering. Tropospheric air mass factors are found to be highly dependent on aerosol scattering, surface albedo and, at long visible wavelengths (about 650 nm), refraction. Absorption measurements of NO2 and O4 are shown to support these conclusions.

  15. Factors associated with sexual risk behavior among persons living with HIV: gender and sexual identity group differences.

    PubMed

    Courtenay-Quirk, Cari; Pals, Sherri L; Colfax, Grant; McKirnan, David; Gooden, Lauren; Eroğlu, Doğan

    2008-09-01

    Factors associated with HIV transmission risk may differ between subgroups of persons living with HIV/AIDS (PLWHA). This study examined such factors in a sample of PLWHA recruited in 3 US metropolitan areas. Sexually active participants were categorized as gay or bisexual men (GBM) (n = 545), heterosexual men (HSM, n = 223), or women (n = 214). Of 982 participants, 27.1% reported serodiscordant unprotected anal or vaginal sex (SDUAV). SDUAV was associated with multiple (2 or more) partners, using poppers, and lower safer sex self-efficacy among GBM. SDUAV was associated with multiple partners among HSM. Among women, factors examined were not associated with SDUAV. These findings are consistent with prior research and facilitate our ability to target those who may be most at risk for transmitting HIV among HIV-positive GBM. More research must be conducted to identify factors associated with risk behavior among HSM and women.

  16. Why College Students Cheat: A Conceptual Model of Five Factors

    ERIC Educational Resources Information Center

    Yu, Hongwei; Glanzer, Perry L.; Johnson, Byron R.; Sriram, Rishi; Moore, Brandon

    2018-01-01

    Though numerous studies have identified factors associated with academic misconduct, few have proposed conceptual models that could make sense of multiple factors. In this study, we used structural equation modeling (SEM) to test a conceptual model of five factors using data from a relatively large sample of 2,503 college students. The results…

  17. The Factor Structure of the English Language Development Assessment: A Confirmatory Factor Analysis

    ERIC Educational Resources Information Center

    Kuriakose, Anju

    2011-01-01

    This study investigated the internal factor structure of the English language development Assessment (ELDA) using confirmatory factor analysis. ELDA is an English language proficiency test developed by a consortium of multiple states and is used to identify and reclassify English language learners in kindergarten to grade 12. Scores on item…

  18. Gender differences in self-rated and partner-rated multiple intelligences: a Portuguese replication.

    PubMed

    Neto, Félix; Furnham, Adrian

    2006-11-01

    The authors examined gender differences and the influence of intelligence quotient (IQ) test experience in the self and partner estimation of H. Gardner's (1999) 10 multiple intelligences. Portuguese students (N = 190) completed a brief questionnaire developed on the basis of an instrument used in previous research (A. Furnham, 2001). Three of the 10 self-estimates yielded significant gender differences. Men believed they were more intelligent than were women on mathematical (logical), spatial, and naturalistic intelligence. Those who had previously completed an IQ test gave higher self-estimates on 2 of the 10 estimates. Factor analysis of the 10 and then 8 self-estimated scores did not confirm Gardner's 3-factor classification of multiple intelligences in this sample.

  19. Inflammatory response and extracorporeal circulation.

    PubMed

    Kraft, Florian; Schmidt, Christoph; Van Aken, Hugo; Zarbock, Alexander

    2015-06-01

    Patients undergoing cardiac surgery with extracorporeal circulation (EC) frequently develop a systemic inflammatory response syndrome. Surgical trauma, ischaemia-reperfusion injury, endotoxaemia and blood contact to nonendothelial circuit compounds promote the activation of coagulation pathways, complement factors and a cellular immune response. This review discusses the multiple pathways leading to endothelial cell activation, neutrophil recruitment and production of reactive oxygen species and nitric oxide. All these factors may induce cellular damage and subsequent organ injury. Multiple organ dysfunction after cardiac surgery with EC is associated with an increased morbidity and mortality. In addition to the pathogenesis of organ dysfunction after EC, this review deals with different therapeutic interventions aiming to alleviate the inflammatory response and consequently multiple organ dysfunction after cardiac surgery. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Using Dynamic Multi-Task Non-Negative Matrix Factorization to Detect the Evolution of User Preferences in Collaborative Filtering

    PubMed Central

    Ju, Bin; Qian, Yuntao; Ye, Minchao; Ni, Rong; Zhu, Chenxi

    2015-01-01

    Predicting what items will be selected by a target user in the future is an important function for recommendation systems. Matrix factorization techniques have been shown to achieve good performance on temporal rating-type data, but little is known about temporal item selection data. In this paper, we developed a unified model that combines Multi-task Non-negative Matrix Factorization and Linear Dynamical Systems to capture the evolution of user preferences. Specifically, user and item features are projected into latent factor space by factoring co-occurrence matrices into a common basis item-factor matrix and multiple factor-user matrices. Moreover, we represented both within and between relationships of multiple factor-user matrices using a state transition matrix to capture the changes in user preferences over time. The experiments show that our proposed algorithm outperforms the other algorithms on two real datasets, which were extracted from Netflix movies and Last.fm music. Furthermore, our model provides a novel dynamic topic model for tracking the evolution of the behavior of a user over time. PMID:26270539

  1. Using Dynamic Multi-Task Non-Negative Matrix Factorization to Detect the Evolution of User Preferences in Collaborative Filtering.

    PubMed

    Ju, Bin; Qian, Yuntao; Ye, Minchao; Ni, Rong; Zhu, Chenxi

    2015-01-01

    Predicting what items will be selected by a target user in the future is an important function for recommendation systems. Matrix factorization techniques have been shown to achieve good performance on temporal rating-type data, but little is known about temporal item selection data. In this paper, we developed a unified model that combines Multi-task Non-negative Matrix Factorization and Linear Dynamical Systems to capture the evolution of user preferences. Specifically, user and item features are projected into latent factor space by factoring co-occurrence matrices into a common basis item-factor matrix and multiple factor-user matrices. Moreover, we represented both within and between relationships of multiple factor-user matrices using a state transition matrix to capture the changes in user preferences over time. The experiments show that our proposed algorithm outperforms the other algorithms on two real datasets, which were extracted from Netflix movies and Last.fm music. Furthermore, our model provides a novel dynamic topic model for tracking the evolution of the behavior of a user over time.

  2. Neural Stem Cell Differentiation Using Microfluidic Device-Generated Growth Factor Gradient.

    PubMed

    Kim, Ji Hyeon; Sim, Jiyeon; Kim, Hyun-Jung

    2018-04-11

    Neural stem cells (NSCs) have the ability to self-renew and differentiate into multiple nervous system cell types. During embryonic development, the concentrations of soluble biological molecules have a critical role in controlling cell proliferation, migration, differentiation and apoptosis. In an effort to find optimal culture conditions for the generation of desired cell types in vitro , we used a microfluidic chip-generated growth factor gradient system. In the current study, NSCs in the microfluidic device remained healthy during the entire period of cell culture, and proliferated and differentiated in response to the concentration gradient of growth factors (epithermal growth factor and basic fibroblast growth factor). We also showed that overexpression of ASCL1 in NSCs increased neuronal differentiation depending on the concentration gradient of growth factors generated in the microfluidic gradient chip. The microfluidic system allowed us to study concentration-dependent effects of growth factors within a single device, while a traditional system requires multiple independent cultures using fixed growth factor concentrations. Our study suggests that the microfluidic gradient-generating chip is a powerful tool for determining the optimal culture conditions.

  3. Defining Success in Adult Basic Education Settings: Multiple Stakeholders, Multiple Perspectives

    PubMed Central

    Tighe, Elizabeth L.; Barnes, Adrienne E.; Connor, Carol M.; Steadman, Sharilyn C.

    2015-01-01

    This study employed quantitative and qualitative research approaches to investigate what constitutes “success” in Adult Basic Education (ABE) programs from the perspectives of multiple educational stakeholders: the state funding agency, the teachers, and the students. Success was defined in multiple ways. In the quantitative section of the study, we computed classroom value-added scores (used as a metric of the state’s definition of success) to identify more and less effective ABE classrooms in two Florida counties. In the qualitative section of the study, we observed and conducted interviews with teachers and students in the selected classrooms to investigate how these stakeholders defined success in ABE. Iterative consideration of the qualitative data revealed three principal markers of success: (a) instructional strategies and teacher-student interactions; (b) views on standardized testing; and (c) student motivational factors. In general, classrooms with higher value-added scores were characterized by multiple instructional approaches, positive and collaborative teacher-student interactions, and students engaging in goal setting and citing motivational factors such as family and personal fulfillment. The implications for ABE programs are discussed. PMID:26279590

  4. EGFR Ligands Drive Multipotential Stromal Cells to Produce Multiple Growth Factors and Cytokines via Early Growth Response-1

    PubMed Central

    Kerpedjieva, Svetoslava S.; Kim, Duk Soo; Barbeau, Dominique J.

    2012-01-01

    Cell therapy with adult bone marrow multipotential stromal cells/mesenchymal stem cells (MSCs) presents a promising approach to promote wound healing and tissue regeneration. The strong paracrine capability of various growth factors and cytokines is a key mechanism of MSC-mediated wound healing and tissue regeneration, and the goal of this study is to understand the underlying mechanism that supports the strong paracrine machineries in MSCs. Microarray database analyses revealed that early growth response-1 (EGR1) is highly expressed in MSCs. Our previous studies showed that epidermal growth factor (EGF) treatment induces growth factor production in MSCs in vitro. Since EGF strongly upregulates EGR1, we hypothesized that EGF receptor (EGFR)–EGR1 signaling plays a pivotal role in MSC paracrine activity. EGF treatment upregulated the gene expression of growth factors and cytokines, including EGFR ligands in a protein kinase C (PKC)- and/or mitogen-activated protein kinase–extracellular-signal-regulated kinase-dependent manner, and it was reversed by shRNA against EGR1. PKC activator phorbol 12-myristate 13-acetate enhanced EGFR tyrosyl phosphorylation and upregulated the gene expression of growth factors and cytokines in a heparin-binding EGF-like growth factor (HBEGF) inhibitor CRM197 sensitive manner, indicating an involvement of autocrined HBEGF in the downstream of PKC signaling. Moreover, stimulation with growth factors and cytokines induced the expression of EGFR ligands, presumably via EGR1 upregulation. These data indicate EGR1 as a convergence point of multiple signaling pathways, which in turn augments the production of multiple growth factors and cytokines by enhancing the autocrine signaling with EGFR ligands. PMID:22316125

  5. EGFR ligands drive multipotential stromal cells to produce multiple growth factors and cytokines via early growth response-1.

    PubMed

    Kerpedjieva, Svetoslava S; Kim, Duk Soo; Barbeau, Dominique J; Tamama, Kenichi

    2012-09-01

    Cell therapy with adult bone marrow multipotential stromal cells/mesenchymal stem cells (MSCs) presents a promising approach to promote wound healing and tissue regeneration. The strong paracrine capability of various growth factors and cytokines is a key mechanism of MSC-mediated wound healing and tissue regeneration, and the goal of this study is to understand the underlying mechanism that supports the strong paracrine machineries in MSCs. Microarray database analyses revealed that early growth response-1 (EGR1) is highly expressed in MSCs. Our previous studies showed that epidermal growth factor (EGF) treatment induces growth factor production in MSCs in vitro. Since EGF strongly upregulates EGR1, we hypothesized that EGF receptor (EGFR)-EGR1 signaling plays a pivotal role in MSC paracrine activity. EGF treatment upregulated the gene expression of growth factors and cytokines, including EGFR ligands in a protein kinase C (PKC)- and/or mitogen-activated protein kinase-extracellular-signal-regulated kinase-dependent manner, and it was reversed by shRNA against EGR1. PKC activator phorbol 12-myristate 13-acetate enhanced EGFR tyrosyl phosphorylation and upregulated the gene expression of growth factors and cytokines in a heparin-binding EGF-like growth factor (HBEGF) inhibitor CRM197 sensitive manner, indicating an involvement of autocrined HBEGF in the downstream of PKC signaling. Moreover, stimulation with growth factors and cytokines induced the expression of EGFR ligands, presumably via EGR1 upregulation. These data indicate EGR1 as a convergence point of multiple signaling pathways, which in turn augments the production of multiple growth factors and cytokines by enhancing the autocrine signaling with EGFR ligands.

  6. Multiple risk factor interventions for primary prevention of coronary heart disease

    PubMed Central

    Ebrahim, Shah; Beswick, Andrew; Burke, Margaret; Smith, George Davey

    2014-01-01

    Background Primary prevention programmes in many countries attempt to reduce mortality and morbidity due to coronary heart disease (CHD) through risk factor modification. It is widely believed that multiple risk factor intervention using counselling and educational methods is efficacious and cost-effective and should be expanded. Recent trials examining risk factor changes have cast considerable doubt on the effectiveness of these multiple risk factor interventions. Objectives To assess the effects of multiple risk factor intervention for reducing cardiovascular risk factors, total mortality, and mortality from CHD among adults without clinical evidence of established cardiovascular disease. Search strategy MEDLINE was searched for the original review to 1995. This was updated by searching the Cochrane Central Register of Controlled Trials on The Cochrane Library Issue 3 2001, MEDLINE(2000 to September 2001) and EMBASE (1998 to September 2001). Selection criteria Intervention studies using counselling or education to modify more than one cardiovascular risk factor in adults from general populations, occupational groups, or high risk groups. Trials of less than 6 months duration were excluded. Data collection and analysis Data were extracted by two reviewers independently. Investigators were contacted to obtain missing information. Main results A total of 39 trials were found of which ten reported clinical event data. In the ten trials with clinical event end-points, the pooled odds ratios for total and CHD mortality were 0.96 (95% confidence intervals (CI) 0.92 to 1.01) and 0.96 (95% CI 0.89 to 1.04) respectively. Net changes in systolic and diastolic blood pressure, and blood cholesterol were (weighted mean differences) −3.6 mmHg (95% CI −3.9 to −3.3 mmHg), −2.8 mmHg (95% CI −2.9 to −2.6 mmHg) and −0.07 mMol/l (95% CI −0.8 to −0.06 mMol/l) respectively. Odds of reduction in smoking prevalence was 20% (95% CI 8% to 31%). Statistical heterogeneity between the studies with respect to mortality and risk factor changes was due to trials focusing on hypertensive participants and those using considerable amounts of drug treatment. Authors’ conclusions The pooled effects suggest multiple risk factor intervention has no effect on mortality. However, a small, but potentially important, benefit of treatment (about a 10% reduction in CHD mortality) may have been missed. Risk factor changes were relatively modest, were related to the amount of pharmacological treatment used, and in some cases may have been over-estimated because of regression to the mean effects, lack of intention to treat analyses, habituation to blood pressure measurement, and use of self-reports of smoking. Interventions using personal or family counselling and education with or without pharmacological treatments appear to be more effective at achieving risk factor reduction and consequent reductions in mortality in high risk hypertensive populations. The evidence suggests that such interventions have limited utility in the general population. PMID:17054138

  7. Multiple Interacting Risk Factors: On Methods for Allocating Risk Factor Interactions.

    PubMed

    Price, Bertram; MacNicoll, Michael

    2015-05-01

    A persistent problem in health risk analysis where it is known that a disease may occur as a consequence of multiple risk factors with interactions is allocating the total risk of the disease among the individual risk factors. This problem, referred to here as risk apportionment, arises in various venues, including: (i) public health management, (ii) government programs for compensating injured individuals, and (iii) litigation. Two methods have been described in the risk analysis and epidemiology literature for allocating total risk among individual risk factors. One method uses weights to allocate interactions among the individual risk factors. The other method is based on risk accounting axioms and finding an optimal and unique allocation that satisfies the axioms using a procedure borrowed from game theory. Where relative risk or attributable risk is the risk measure, we find that the game-theory-determined allocation is the same as the allocation where risk factor interactions are apportioned to individual risk factors using equal weights. Therefore, the apportionment problem becomes one of selecting a meaningful set of weights for allocating interactions among the individual risk factors. Equal weights and weights proportional to the risks of the individual risk factors are discussed. © 2015 Society for Risk Analysis.

  8. 48 CFR 538.270 - Evaluation of multiple award schedule (MAS) offers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES ADMINISTRATION SPECIAL CATEGORIES OF CONTRACTING FEDERAL SUPPLY SCHEDULE CONTRACTING Establishing and Administering Federal Supply Schedules 538.270 Evaluation of multiple award schedule (MAS) offers... determining the Government's price negotiation objectives, consider the following factors: (1) Aggregate...

  9. The multiple-hit pathogenesis of non-alcoholic fatty liver disease (NAFLD).

    PubMed

    Buzzetti, Elena; Pinzani, Massimo; Tsochatzis, Emmanuel A

    2016-08-01

    Nonalcoholic fatty liver disease (NAFLD) is increasingly prevalent and represents a growing challenge in terms of prevention and treatment. Despite its high prevalence, only a small minority of affected patients develops inflammation and subsequently fibrosis and chronic liver disease, while most of them only exhibit simple steatosis. In this context, the full understanding of the mechanisms underlying the development of NAFLD and non-alcoholic steatohepatitis (NASH) is of extreme importance; despite advances in this field, knowledge on the pathogenesis of NAFLD is still incomplete. The 'two-hit' hypothesis is now obsolete, as it is inadequate to explain the several molecular and metabolic changes that take place in NAFLD. The "multiple hit" hypothesis considers multiple insults acting together on genetically predisposed subjects to induce NAFLD and provides a more accurate explanation of NAFLD pathogenesis. Such hits include insulin resistance, hormones secreted from the adipose tissue, nutritional factors, gut microbiota and genetic and epigenetic factors. In this article, we review the factors that form this hypothesis. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Experimental verification of a gain reduction model for the space charge effect in a wire chamber

    NASA Astrophysics Data System (ADS)

    Nagakura, Naoki; Fujii, Kazuki; Harayama, Isao; Kato, Yu; Sekiba, Daiichiro; Watahiki, Yumi; Yamashita, Satoru

    2018-01-01

    A wire chamber often suffers significant saturation of the multiplication factor when the electric field around its wires is strong. An analytical model of this effect has previously been proposed [Y. Arimoto et al., Nucl. Instrum. Meth. Phys. Res. A 799, 187 (2015)], in which the saturation was described by the multiplication factor, energy deposit density per wire length, and one constant parameter. In order to confirm the validity of this model, a multi-wire drift chamber was developed and irradiated by a MeV-range proton beam at the University of Tsukuba. The saturation effect was compared for energy deposits ranging from 70 keV/cm to 180 keV/cm and multiplication factors 3× 103 to 3× 104. The chamber was rotated with respect to the proton beam in order to vary the space charge density around the wires. The energy deposit distribution corrected for the effect was consistent with the result of a Monte Carlo simulation, thus validating the proposed model.

  11. Stochastic nature of Landsat MSS data

    NASA Technical Reports Server (NTRS)

    Labovitz, M. L.; Masuoka, E. J.

    1987-01-01

    A multiple series generalization of the ARIMA models is used to model Landsat MSS scan lines as sequences of vectors, each vector having four elements (bands). The purpose of this work is to investigate if Landsat scan lines can be described by a general multiple series linear stochastic model and if the coefficients of such a model vary as a function of satellite system and target attributes. To accomplish this objective, an exploratory experimental design was set up incorporating six factors, four representing target attributes - location, cloud cover, row (within location), and column (within location) - and two factors representing system attributes - satellite number and detector bank. Each factor was included in the design at two levels and, with two replicates per treatment, 128 scan lines were analyzed. The results of the analysis suggests that a multiple AR(4) model is an adequate representation across all scan lines. Furthermore, the coefficients of the AR(4) model vary with location, particularly changes in physiography (slope regimes), and with percent cloud cover, but are insensitive to changes in system attributes.

  12. Ibrutinib targets microRNA-21 in multiple myeloma cells by inhibiting NF-κB and STAT3.

    PubMed

    Ma, Jing; Gong, Wei; Liu, Su; Li, Qian; Guo, Mengzheng; Wang, Jinhan; Wang, Suying; Chen, Naiyao; Wang, Yafei; Liu, Qiang; Zhao, Hui

    2018-01-01

    The oncogenic microRNA-21 contributes to the pathogenesis of multiple myeloma. Ibrutinib (also referred to as PCI-32765), an inhibitor of Bruton's tyrosine kinase, while its effects on multiple myeloma have not been well described. Here, we show that microRNA-21 is an oncogenic marker closely linked with progression of multiple myeloma. Moreover, ibrutinib attenuates microRNA-21 expression in multiple myeloma cells by inhibiting nuclear factor-κB and signal transducer and activator of transcription 3 signaling pathways. Taken together, our results suggest that ibrutinib is a promising potential treatment for multiple myeloma. Further investigation of mechanisms of ibrutinib function in multiple myeloma will be necessary to evaluate its use as a novel multiple myeloma treatment.

  13. FACTORS IMPLICATED IN AMPHIBIAN POPULATION DECLINES IN THE UNITED STATES

    EPA Science Inventory

    Factors adversely affecting amphibian populations in the US were evaluated using information from species accounts written in a standardized format by multiple authors (Volume 2 of this book). For each species, factors implicated by the authors (i.e., known or suspected) as affec...

  14. Psychosocial Predictors and Correlates of Suicidality in Teenage Latino Males

    ERIC Educational Resources Information Center

    Locke, Thomas F.; Newcomb, Michael D.

    2005-01-01

    Multiple ecodevelopmental factors were tested as they influence suicidality in a community sample of Latino adolescent males. Risk factors tested included childhood maltreatment, parental alcohol-related problems, and polysubstance problems. Protective factors included general self-efficacy, social conformity, and family bonding. Male participants…

  15. Listening to food workers: Factors that impact proper health and hygiene practice in food service

    PubMed Central

    Clegg Smith, Katherine; Neff, Roni A.; Pollack, Keshia M.; Ensminger, Margaret

    2015-01-01

    Background Foodborne disease is a significant problem worldwide. Research exploring sources of outbreaks indicates a pronounced role for food workers' improper health and hygiene practice. Objective To investigate food workers' perceptions of factors that impact proper food safety practice. Method Interviews with food service workers in Baltimore, MD, USA discussing food safety practices and factors that impact implementation in the workplace. A social ecological model organizes multiple levels of influence on health and hygiene behavior. Results Issues raised by interviewees include factors across the five levels of the social ecological model, and confirm findings from previous work. Interviews also reveal many factors not highlighted in prior work, including issues with food service policies and procedures, working conditions (e.g., pay and benefits), community resources, and state and federal policies. Conclusion Food safety interventions should adopt an ecological orientation that accounts for factors at multiple levels, including workers' social and structural context, that impact food safety practice. PMID:26243248

  16. Analyzing the effect of selected control policy measures and sociodemographic factors on alcoholic beverage consumption in Europe within the AMPHORA project: statistical methods.

    PubMed

    Baccini, Michela; Carreras, Giulia

    2014-10-01

    This paper describes the methods used to investigate variations in total alcoholic beverage consumption as related to selected control intervention policies and other socioeconomic factors (unplanned factors) within 12 European countries involved in the AMPHORA project. The analysis presented several critical points: presence of missing values, strong correlation among the unplanned factors, long-term waves or trends in both the time series of alcohol consumption and the time series of the main explanatory variables. These difficulties were addressed by implementing a multiple imputation procedure for filling in missing values, then specifying for each country a multiple regression model which accounted for time trend, policy measures and a limited set of unplanned factors, selected in advance on the basis of sociological and statistical considerations are addressed. This approach allowed estimating the "net" effect of the selected control policies on alcohol consumption, but not the association between each unplanned factor and the outcome.

  17. Bioinformatics approaches to predict target genes from transcription factor binding data.

    PubMed

    Essebier, Alexandra; Lamprecht, Marnie; Piper, Michael; Bodén, Mikael

    2017-12-01

    Transcription factors regulate gene expression and play an essential role in development by maintaining proliferative states, driving cellular differentiation and determining cell fate. Transcription factors are capable of regulating multiple genes over potentially long distances making target gene identification challenging. Currently available experimental approaches to detect distal interactions have multiple weaknesses that have motivated the development of computational approaches. Although an improvement over experimental approaches, existing computational approaches are still limited in their application, with different weaknesses depending on the approach. Here, we review computational approaches with a focus on data dependency, cell type specificity and usability. With the aim of identifying transcription factor target genes, we apply available approaches to typical transcription factor experimental datasets. We show that approaches are not always capable of annotating all transcription factor binding sites; binding sites should be treated disparately; and a combination of approaches can increase the biological relevance of the set of genes identified as targets. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Patterns of evolution at the gametophytic self-incompatibility Sorbus aucuparia (Pyrinae) S pollen genes support the non-self recognition by multiple factors model

    PubMed Central

    Aguiar, Bruno; Vieira, Jorge; Cunha, Ana E.; Fonseca, Nuno A.; Reboiro-Jato, David; Reboiro-Jato, Miguel; Fdez-Riverola, Florentino; Raspé, Olivier; Vieira, Cristina P.

    2013-01-01

    S-RNase-based gametophytic self-incompatibility evolved once before the split of the Asteridae and Rosidae. In Prunus (tribe Amygdaloideae of Rosaceae), the self-incompatibility S-pollen is a single F-box gene that presents the expected evolutionary signatures. In Malus and Pyrus (subtribe Pyrinae of Rosaceae), however, clusters of F-box genes (called SFBBs) have been described that are expressed in pollen only and are linked to the S-RNase gene. Although polymorphic, SFBB genes present levels of diversity lower than those of the S-RNase gene. They have been suggested as putative S-pollen genes, in a system of non-self recognition by multiple factors. Subsets of allelic products of the different SFBB genes interact with non-self S-RNases, marking them for degradation, and allowing compatible pollinations. This study performed a detailed characterization of SFBB genes in Sorbus aucuparia (Pyrinae) to address three predictions of the non-self recognition by multiple factors model. As predicted, the number of SFBB genes was large to account for the many S-RNase specificities. Secondly, like the S-RNase gene, the SFBB genes were old. Thirdly, amino acids under positive selection—those that could be involved in specificity determination—were identified when intra-haplotype SFBB genes were analysed using codon models. Overall, the findings reported here support the non-self recognition by multiple factors model. PMID:23606363

  19. Using impedance cardiography to detect subclinical cardiovascular disease in women with multiple risk factors: a pilot study.

    PubMed

    Demarzo, Arthur P

    2009-01-01

    Early detection of cardiovascular disease (CVD) could initiate appropriate treatment and prevent progression. This study used impedance cardiography (ICG) waveform analysis with postural change to detect functional CVD in women older than 40 years with no history of CVD and >or=2 of the following risk factors: cigarette smoking, poor diet, physical inactivity, central adiposity, family history of premature CVD, hypertension, and dyslipidemia. A study group of 32 women underwent ICG in standing and supine positions. An age-matched control group had 20 women with an active lifestyle, no risk factors, and no history of CVD. All women in the control group had normal ICG data. All women in the study group had some abnormal ICG data, with 28 (87.5%) having multiple ICG abnormalities. ICG data indicated that 13 (40.6%) had ventricular dysfunction, 14 (43.8%) had high vascular resistive load, and 30 (93.8%) had elevated vascular pulsatile load. The data suggest that subclinical CVD, detectable by ICG, is prevalent in women older than 40 years with multiple risk factors. Abnormal ICG results could expedite the initiation of customized treatment as part of a preventive approach to CVD. (c) 2009 Wiley Periodicals, Inc.

  20. Parent-reported suicidal behavior and correlates among adolescents in China.

    PubMed

    Liu, Xianchen; Sun, Zhenxiao; Yang, Yanyun

    2008-01-01

    Suicidal risk begins to increase during adolescence and is associated with multiple biological, psychological, social, and cultural factors. This study examined the prevalence and psychosocial factors of parent-reported suicidal behavior in Chinese adolescents. A community sample of 1920 adolescents in China participated in an epidemiological study. Parents completed a structured questionnaire including child suicidal behavior, illness history, mental health problems, family history, parenting, and family environment. Multiple logistic regression was used for data analysis. Overall, 2.4% of the sample talked about suicide in the previous 6 months, 3.2% had deliberately hurt themselves or attempted suicide, and 5.1% had either suicidal talk or self-harm. The rate of suicidal behavior increased as adolescents aged. Multivariate logistic regression indicated that the following factors were significantly associated with elevated risk for suicidal behavior: depressive/anxious symptoms, poor maternal health, family conflict, and physical punishment of parental discipline style. Suicidal behavior was reported by parents. No causal relationships could be made based on cross-sectional data. The prevalence rate of parent-reported suicidal behavior is markedly lower than self-reported rate in previous research. Depressive/anxious symptoms and multiple family environmental factors are associated with suicidal behavior in Chinese adolescents.

  1. Microarray gene expression profiling analysis combined with bioinformatics in multiple sclerosis.

    PubMed

    Liu, Mingyuan; Hou, Xiaojun; Zhang, Ping; Hao, Yong; Yang, Yiting; Wu, Xiongfeng; Zhu, Desheng; Guan, Yangtai

    2013-05-01

    Multiple sclerosis (MS) is the most prevalent demyelinating disease and the principal cause of neurological disability in young adults. Recent microarray gene expression profiling studies have identified several genetic variants contributing to the complex pathogenesis of MS, however, expressional and functional studies are still required to further understand its molecular mechanism. The present study aimed to analyze the molecular mechanism of MS using microarray analysis combined with bioinformatics techniques. We downloaded the gene expression profile of MS from Gene Expression Omnibus (GEO) and analysed the microarray data using the differentially coexpressed genes (DCGs) and links package in R and Database for Annotation, Visualization and Integrated Discovery. The regulatory impact factor (RIF) algorithm was used to measure the impact factor of transcription factor. A total of 1,297 DCGs between MS patients and healthy controls were identified. Functional annotation indicated that these DCGs were associated with immune and neurological functions. Furthermore, the RIF result suggested that IKZF1, BACH1, CEBPB, EGR1, FOS may play central regulatory roles in controlling gene expression in the pathogenesis of MS. Our findings confirm the presence of multiple molecular alterations in MS and indicate the possibility for identifying prognostic factors associated with MS pathogenesis.

  2. Construct validity of ADHD/ODD rating scales: recommendations for the evaluation of forthcoming DSM-V ADHD/ODD scales.

    PubMed

    Burns, G Leonard; Walsh, James A; Servera, Mateu; Lorenzo-Seva, Urbano; Cardo, Esther; Rodríguez-Fornells, Antoni

    2013-01-01

    Exploratory structural equation modeling (SEM) was applied to a multiple indicator (26 individual symptom ratings) by multitrait (ADHD-IN, ADHD-HI and ODD factors) by multiple source (mothers, fathers and teachers) model to test the invariance, convergent and discriminant validity of the Child and Adolescent Disruptive Behavior Inventory with 872 Thai adolescents and the ADHD Rating Scale-IV and ODD scale of the Disruptive Behavior Inventory with 1,749 Spanish children. Most of the individual ADHD/ODD symptoms showed convergent and discriminant validity with the loadings and thresholds being invariant over mothers, fathers and teachers in both samples (the three latent factor means were higher for parents than teachers). The ADHD-IN, ADHD-HI and ODD latent factors demonstrated convergent and discriminant validity between mothers and fathers within the two samples. Convergent and discriminant validity between parents and teachers for the three factors was either absent (Thai sample) or only partial (Spanish sample). The application of exploratory SEM to a multiple indicator by multitrait by multisource model should prove useful for the evaluation of the construct validity of the forthcoming DSM-V ADHD/ODD rating scales.

  3. Tehran Survey of Potential Risk Factors for Multiple Births.

    PubMed

    Omani Samani, Reza; Almasi-Hashiani, Amir; Vesali, Samira; Shokri, Fatemeh; Cheraghi, Rezvaneh; Torkestani, Farahnaz; Sepidarkish, Mahdi

    2017-10-01

    The multiple pregnancy incidence is increasing worldwide. This increased incidence is concerning to the health care system. This study aims to determine the frequency of multiple pregnancy and identify factors that affect this frequency in Tehran, Iran. This cross-sectional study included 5170 mothers in labor between July 6-21, 2015 from 103 hospitals with Obstetrics and Gynecology Wards. The questionnaire used in this study consisted of five parts: demographic characteristics; information related to pregnancy; information related to the infant; information regarding the multiple pregnancy; and information associated with infertility. We recruited 103 trained midwives to collect data related to the questionnaire from eligible participants through an interview and medical records review. Frequencies and odds ratios (OR) for the association between multiple pregnancy and the selected characteristics (maternal age, economic status, history of multiple pregnancy in first-degree relatives, and reproductive history) were computed by multiple logistic regression. Stata software, version 13 (Stata Corp, College Station, TX, USA) was used for all statistical analyses. Multiple pregnancy had a prevalence of 1.48% [95% confidence interval (CI): 1.19-1.85]. After controlling for confounding variables, we observed a significant association between frequency of multiple pregnancy and mother's age (OR=1.04, 95% CI: 1.001-1.09, P=0.044), assisted reproductive technique (ART, OR=6.11, 95% CI: 1.7- 21.97, P=0.006), and history of multiple pregnancy in the mother's family (OR=5.49, 95% CI: 3.55-9.93, P=0.001). The frequency of multiple pregnancy approximated results reported in previous studies in Iran. Based on the results, we observed significantly greater frequency of multiple pregnancy in older women, those with a history of ART, and a history of multiple pregnancy in the mother's family compared to the other variables. Copyright© by Royan Institute. All rights reserved.

  4. Multiple transgene traits may create un-intended fitness effects in Brassica napus

    EPA Science Inventory

    Increasingly, genetically modified crops are being developed to express multiple “stacked” traits for different types of transgenes, for example, herbicide resistance, insect resistance, crop quality and resistance to environmental factors. The release of crops that express mult...

  5. Prognostic factors for early severity in a childhood multiple sclerosis cohort.

    PubMed

    Mikaeloff, Yann; Caridade, Guillaume; Assi, Saada; Suissa, Samy; Tardieu, Marc

    2006-09-01

    The goal was to identify prognostic factors for an early severe course in a cohort of patients with childhood-onset multiple sclerosis, for the construction of a predictive tool. The cohort consisted of 197 children from the French Kid Sclérose en Plaques neuropediatric cohort with relapsing/remitting multiple sclerosis beginning before the age of 16 years. Patients were included from 1990 to 2003. We used multivariate survival analysis (Cox model) to evaluate the prognostic value of clinical, MRI, and biological covariates at onset for the occurrence of a third attack or severe disability ("severity" outcome). The cohort was monitored for a mean of 5.5 +/- 3.6 years. The "severity" outcome was recorded for 144 patients (73%). The risk of severity was higher for girls, for a time between the first and second attacks of < 1 year, for childhood-onset multiple sclerosis MRI criteria at onset, for an absence of severe mental state changes at onset, and for a progressive course. A derived childhood-onset multiple sclerosis potential index for early severity was found to have a positive predictive value for severity of > 35% for the upper 2 quartiles. The clinical and MRI prognostic factors for early severity that were identified were used as the basis of a predictive tool, which will be validated in another cohort. This tool should make it possible to identify subgroups at risk of early severe disease and should facilitate therapeutic studies.

  6. [High Risk Sex Behaviors and Associated Factors in Young Men in Chengdu].

    PubMed

    2015-11-01

    To determine the prevalence of high risk sex behaviors and associated factors in 18-34 years old men in Chengdu. Methods An anonymous questionnaire survey was conducted in 18-34 years old men selected by multi-stage random sampling in Chengdu. Data of 1536 respondents who reported having sex contacts were analyzed. 23.6% of respondents had multiple sex partners in the past 12 months; 11.8% were involved commercial sex; 9.0% had group sex; 4. 7% had anal sex; 15.6% had never used a condom; 37.7% had sex under the influence of alcohol or drugs. Logistic regression analysis revealed that marital status [married, standardized partial regression coefficient (B) = -0.086, P<0.05] , level of education (bachelor or above, B= -0.063, P<0.05), frequency of exposure to pornography (B=0.058, P<0.05), childhood sexual abuse (B= 0.042, P<0.05), first sexual intercourse at an earlier age (B=0.162, P<0.05), frequency of sex under the influence of alcohol or drugs (B=0.054, P<0.05) were significant predictors of having multiple sexual partners. Sexual orientation, age, smoking, alcohol abuse, drug use, anxiety, depression, childhood physical abuse did not appear to be significant factors associated with having multiple sexual partners. Having multiple sexual partners is the main high risk sex behavior of young men in Chengdu. Childhood sexual abuse and early start of sexual intercourse are the major predictors of having multiple sexual partners.

  7. Patient and cycle characteristics predicting high pregnancy rates with single-embryo transfer: an analysis of the Society for Assisted Reproductive Technology outcomes between 2004 and 2013.

    PubMed

    Mersereau, Jennifer; Stanhiser, Jamie; Coddington, Charles; Jones, Tiffany; Luke, Barbara; Brown, Morton B

    2017-11-01

    To analyze factors associated with high live birth rate and low multiple birth rate in fresh and frozen-thawed assisted reproductive technology (ART) cycles. Retrospective cohort analysis. Not applicable. The study population included 181,523 women undergoing in vitro fertilization with autologous fresh first cycles, 27,033 with fresh first oocyte donor cycles, 37,658 with fresh second cycles, and 35,446 with frozen-thawed second cycles. None. Live birth rate and multiple birth rate after single-embryo transfer (SET) and double embryo transfer (DET) were measured, in addition to cycle characteristics. In patients with favorable prognostic factors, including younger maternal age, transfer of a blastocyst, and additional embryos cryopreserved, the gain in the live birth rate from SET to DET was approximately 10%-15%; however, the multiple birth rate increased from approximately 2% to greater than 49% in both autologous and donor fresh and frozen-thawed transfer cycles. This study reports a 10%-15% reduction in live birth rate and a 47% decrement in multiple birth rate with SET compared with DET in the setting of favorable patient prognostic factors. Our findings present an opportunity to increase the rate of SET across the United States and thereby reduce the multiple birth rate and its associated poor perinatal outcomes with assisted reproductive technology pregnancies. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  8. The effects of multiple interpersonal traumas on psychological maladjustment of sexually abused children in Korea.

    PubMed

    Choi, Ji Young; Oh, Kyung Ja

    2013-02-01

    The purpose of the present study was to explore the effects of multiple interpersonal traumas on psychiatric diagnosis and behavior problems of sexually abused children in Korea. With 495 children (ages 4-13 years) referred to a public counseling center for sexual abuse in Korea, we found significant differences in the rate of psychiatric diagnoses (r = .23) and severity of behavioral problems (internalizing d = 0.49, externalizing d = 0.40, total d = 0.52) between children who were victims of sexual abuse only (n = 362) and youth who were victims of interpersonal trauma experiences in addition to sexual abuse (n = 133). The effects of multiple interpersonal trauma experiences on single versus multiple diagnoses remained significant in the logistic regression analysis where demographic variables, family environmental factors, sexual abuse characteristics, and postincident factors were considered together, odds ratio (OR) = 0.44, 95% confidence interval (CI) = [0.25, 0.77], p < .01. Similarly, multiple regression analyses revealed a significant effect of multiple interpersonal trauma experiences on severity of behavioral problems above and beyond all aforementioned variables (internalizing β =.12, p = .019, externalizing β = .11, p = .036, total β = .14, p =.008). The results suggested that children with multiple interpersonal traumas are clearly at a greater risk for negative consequences following sexual abuse. Copyright © 2013 International Society for Traumatic Stress Studies.

  9. Prediction of hearing outcomes by multiple regression analysis in patients with idiopathic sudden sensorineural hearing loss.

    PubMed

    Suzuki, Hideaki; Tabata, Takahisa; Koizumi, Hiroki; Hohchi, Nobusuke; Takeuchi, Shoko; Kitamura, Takuro; Fujino, Yoshihisa; Ohbuchi, Toyoaki

    2014-12-01

    This study aimed to create a multiple regression model for predicting hearing outcomes of idiopathic sudden sensorineural hearing loss (ISSNHL). The participants were 205 consecutive patients (205 ears) with ISSNHL (hearing level ≥ 40 dB, interval between onset and treatment ≤ 30 days). They received systemic steroid administration combined with intratympanic steroid injection. Data were examined by simple and multiple regression analyses. Three hearing indices (percentage hearing improvement, hearing gain, and posttreatment hearing level [HLpost]) and 7 prognostic factors (age, days from onset to treatment, initial hearing level, initial hearing level at low frequencies, initial hearing level at high frequencies, presence of vertigo, and contralateral hearing level) were included in the multiple regression analysis as dependent and explanatory variables, respectively. In the simple regression analysis, the percentage hearing improvement, hearing gain, and HLpost showed significant correlation with 2, 5, and 6 of the 7 prognostic factors, respectively. The multiple correlation coefficients were 0.396, 0.503, and 0.714 for the percentage hearing improvement, hearing gain, and HLpost, respectively. Predicted values of HLpost calculated by the multiple regression equation were reliable with 70% probability with a 40-dB-width prediction interval. Prediction of HLpost by the multiple regression model may be useful to estimate the hearing prognosis of ISSNHL. © The Author(s) 2014.

  10. The Counseling Competencies Scale: Validation and Refinement

    ERIC Educational Resources Information Center

    Lambie, Glenn W.; Mullen, Patrick R.; Swank, Jacqueline M.; Blount, Ashley

    2018-01-01

    Supervisors evaluated counselors-in-training at multiple points during their practicum experience using the Counseling Competencies Scale (CCS; N = 1,070). The CCS evaluations were randomly split to conduct exploratory factor analysis and confirmatory factor analysis, resulting in a 2-factor model (61.5% of the variance explained).

  11. Childhood Risk Factors in Dually Diagnosed Homeless Adults.

    ERIC Educational Resources Information Center

    Blankertz, Laura E.; And Others

    1993-01-01

    Examined prevalence of five childhood risk factors (sexual abuse, physical abuse, parental mental illness, substance abuse, out-of-home placement) among dually diagnosed (mentally ill and substance abusing) homeless adults (n=156) in rehabilitation programs. Findings suggest that childhood risk factors, whether single or multiple, are very…

  12. A Multi-Domain Model of Risk Factors for ODD Symptoms in a Community Sample of 4-Year-Olds

    ERIC Educational Resources Information Center

    Lavigne, John V.; Gouze, Karen R.; Hopkins, Joyce; Bryant, Fred B.; LeBailly, Susan A.

    2012-01-01

    Few studies have been designed to assess the pathways by which risk factors are associated with symptoms of psychopathology across multiple domains, including contextual factors, parental depression, parenting, and child characteristics. The present study examines a cross-sectional model of risk factors for symptoms of Oppositional Defiant…

  13. Comparative quantification of health risks: Conceptual framework and methodological issues

    PubMed Central

    Murray, Christopher JL; Ezzati, Majid; Lopez, Alan D; Rodgers, Anthony; Vander Hoorn, Stephen

    2003-01-01

    Reliable and comparable analysis of risks to health is key for preventing disease and injury. Causal attribution of morbidity and mortality to risk factors has traditionally been conducted in the context of methodological traditions of individual risk factors, often in a limited number of settings, restricting comparability. In this paper, we discuss the conceptual and methodological issues for quantifying the population health effects of individual or groups of risk factors in various levels of causality using knowledge from different scientific disciplines. The issues include: comparing the burden of disease due to the observed exposure distribution in a population with the burden from a hypothetical distribution or series of distributions, rather than a single reference level such as non-exposed; considering the multiple stages in the causal network of interactions among risk factor(s) and disease outcome to allow making inferences about some combinations of risk factors for which epidemiological studies have not been conducted, including the joint effects of multiple risk factors; calculating the health loss due to risk factor(s) as a time-indexed "stream" of disease burden due to a time-indexed "stream" of exposure, including consideration of discounting; and the sources of uncertainty. PMID:12780936

  14. Breast Cancer and Modifiable Lifestyle Factors in Argentinean Women: Addressing Missing Data in a Case-Control Study

    PubMed Central

    Coquet, Julia Becaria; Tumas, Natalia; Osella, Alberto Ruben; Tanzi, Matteo; Franco, Isabella; Diaz, Maria Del Pilar

    2016-01-01

    A number of studies have evidenced the effect of modifiable lifestyle factors such as diet, breastfeeding and nutritional status on breast cancer risk. However, none have addressed the missing data problem in nutritional epidemiologic research in South America. Missing data is a frequent problem in breast cancer studies and epidemiological settings in general. Estimates of effect obtained from these studies may be biased, if no appropriate method for handling missing data is applied. We performed Multiple Imputation for missing values on covariates in a breast cancer case-control study of Córdoba (Argentina) to optimize risk estimates. Data was obtained from a breast cancer case control study from 2008 to 2015 (318 cases, 526 controls). Complete case analysis and multiple imputation using chained equations were the methods applied to estimate the effects of a Traditional dietary pattern and other recognized factors associated with breast cancer. Physical activity and socioeconomic status were imputed. Logistic regression models were performed. When complete case analysis was performed only 31% of women were considered. Although a positive association of Traditional dietary pattern and breast cancer was observed from both approaches (complete case analysis OR=1.3, 95%CI=1.0-1.7; multiple imputation OR=1.4, 95%CI=1.2-1.7), effects of other covariates, like BMI and breastfeeding, were only identified when multiple imputation was considered. A Traditional dietary pattern, BMI and breastfeeding are associated with the occurrence of breast cancer in this Argentinean population when multiple imputation is appropriately performed. Multiple Imputation is suggested in Latin America’s epidemiologic studies to optimize effect estimates in the future. PMID:27892664

  15. Body Esteem Among Women with Multiple Sclerosis and its Relationship with Demographic, Clinical and Socio-Psychological Factors.

    PubMed

    Wilski, M; Tasiemski, T; Dąbrowski, A

    2016-06-01

    The principal aim of this study was to verify if specific socio-demographic, clinical, and socio-psychological factors are correlates of body esteem in women with multiple sclerosis (MS). The study included 185 women with MS who completed the Body Esteem Scale (BES), Rosenberg Self-Esteem Scale (RSES), Multiple Sclerosis Impact Scale (MSIS-29), Brief Illness Perception Questionnaire (B-IPQ), Actually Received Support Scale (a part of the Berlin Social Support Scale), and Expanded Disability Status Scale (EDSS). The patients were recruited as a result of cooperation with the Multiple Sclerosis Rehabilitation Centre in Borne Sulinowo and Polish Society of Multiple Sclerosis. The demographic characteristics of the participants and their illness-related problems were determined with a self-report survey. A hierarchical multiple regression revealed that four factors, psychological condition (R (2) = 0.23, p ≤ 0.001), received support (R (2) = 0.28, p ≤ 0.001), personal control (R (2) = 0.30, p ≤ 0.001), and physical condition (R (2) = 0.31, p ≤ 0.001), were significant correlates of the general body esteem in our study group of women with MS. The model explained 31 % of variance in body esteem. Positive body esteem, an important component of self-esteem in women with MS, is associated with better social support, overcoming negative illness-related appraisals and improvement of psychological well-being. Subjective perception of a negative impact of MS on one's physical condition may be helpful in the identification of women with MS being at increased risk of decreased body esteem.

  16. Multi-objective optimization for generating a weighted multi-model ensemble

    NASA Astrophysics Data System (ADS)

    Lee, H.

    2017-12-01

    Many studies have demonstrated that multi-model ensembles generally show better skill than each ensemble member. When generating weighted multi-model ensembles, the first step is measuring the performance of individual model simulations using observations. There is a consensus on the assignment of weighting factors based on a single evaluation metric. When considering only one evaluation metric, the weighting factor for each model is proportional to a performance score or inversely proportional to an error for the model. While this conventional approach can provide appropriate combinations of multiple models, the approach confronts a big challenge when there are multiple metrics under consideration. When considering multiple evaluation metrics, it is obvious that a simple averaging of multiple performance scores or model ranks does not address the trade-off problem between conflicting metrics. So far, there seems to be no best method to generate weighted multi-model ensembles based on multiple performance metrics. The current study applies the multi-objective optimization, a mathematical process that provides a set of optimal trade-off solutions based on a range of evaluation metrics, to combining multiple performance metrics for the global climate models and their dynamically downscaled regional climate simulations over North America and generating a weighted multi-model ensemble. NASA satellite data and the Regional Climate Model Evaluation System (RCMES) software toolkit are used for assessment of the climate simulations. Overall, the performance of each model differs markedly with strong seasonal dependence. Because of the considerable variability across the climate simulations, it is important to evaluate models systematically and make future projections by assigning optimized weighting factors to the models with relatively good performance. Our results indicate that the optimally weighted multi-model ensemble always shows better performance than an arithmetic ensemble mean and may provide reliable future projections.

  17. Dynamic Modulation of Expression of Lentiviral Restriction Factors in Primary CD4+ T Cells following Simian Immunodeficiency Virus Infection.

    PubMed

    Rahmberg, Andrew R; Rajakumar, Premeela A; Billingsley, James M; Johnson, R Paul

    2017-04-01

    Although multiple restriction factors have been shown to inhibit HIV/SIV replication, little is known about their expression in vivo Expression of 45 confirmed and putative HIV/SIV restriction factors was analyzed in CD4 + T cells from peripheral blood and the jejunum in rhesus macaques, revealing distinct expression patterns in naive and memory subsets. In both peripheral blood and the jejunum, memory CD4 + T cells expressed higher levels of multiple restriction factors compared to naive cells. However, relative to their expression in peripheral blood CD4 + T cells, jejunal CCR5 + CD4 + T cells exhibited significantly lower expression of multiple restriction factors, including APOBEC3G , MX2 , and TRIM25 , which may contribute to the exquisite susceptibility of these cells to SIV infection. In vitro stimulation with anti-CD3/CD28 antibodies or type I interferon resulted in upregulation of distinct subsets of multiple restriction factors. After infection of rhesus macaques with SIVmac239, the expression of most confirmed and putative restriction factors substantially increased in all CD4 + T cell memory subsets at the peak of acute infection. Jejunal CCR5 + CD4 + T cells exhibited the highest levels of SIV RNA, corresponding to the lower restriction factor expression in this subset relative to peripheral blood prior to infection. These results illustrate the dynamic modulation of confirmed and putative restriction factor expression by memory differentiation, stimulation, tissue microenvironment and SIV infection and suggest that differential expression of restriction factors may play a key role in modulating the susceptibility of different populations of CD4 + T cells to lentiviral infection. IMPORTANCE Restriction factors are genes that have evolved to provide intrinsic defense against viruses. HIV and simian immunodeficiency virus (SIV) target CD4 + T cells. The baseline level of expression in vivo and degree to which expression of restriction factors is modulated by conditions such as CD4 + T cell differentiation, stimulation, tissue location, or SIV infection are currently poorly understood. We measured the expression of 45 confirmed and putative restriction factors in primary CD4 + T cells from rhesus macaques under various conditions, finding dynamic changes in each state. Most dramatically, in acute SIV infection, the expression of almost all target genes analyzed increased. These are the first measurements of many of these confirmed and putative restriction factors in primary cells or during the early events after SIV infection and suggest that the level of expression of restriction factors may contribute to the differential susceptibility of CD4 + T cells to SIV infection. Copyright © 2017 American Society for Microbiology.

  18. Mild cognitive impairment in symptomatic and asymptomatic cerebrovascular disease.

    PubMed

    Popović, Irena Martinić; Serić, Vesna; Demarin, Vida

    2007-06-15

    We tried to evaluate and to compare usefulness of two brief cognitive tests in early detection of cognitive decline in subjects with increased cerebrovascular (CV) risk. As CV risk factors are recognised as important in etiology of dementia, we also aimed to determine the possible associations of specific CV risk factors and cognitive results. Patients (PGs) with first-ever stroke or TIA (N=110) and CV symptoms-free controls (CGs) with CV risk factors present (N=45) matched for age, gender and education level were tested using Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) on admission, at three- and six-month points. In all subjects, detailed CV risk factors profile was assessed. We observed the decrement in cognitive performance during the six-month study period in both groups, more evident if MoCA (p<0.001) than if MMSE was used (p=0.022). Six months after first stroke/TIA 83.6% PGs scored below normal range on MoCA. In PGs, positive associations for cognitive decrement and multiple CV risk factors (>2) were found (p=0.034 for MMSE; p=0.002 for MoCA). In CGs, positive associations were found for cognitive decrement and arterial hypertension with increased IMT values (p<0.001 for MMSE) and for multiple CV risk factors and arterial hypertension (p=0.003 for MoCA). The use of MoCA could aid to early recognition of cognitive deficits in persons with increased CV risk. Individuals with multiple CV risk factors seem to have increased risk of cognitive decline.

  19. Cell- and virus-mediated regulation of the barrier-to-autointegration factor's phosphorylation state controls its DNA binding, dimerization, subcellular localization, and antipoxviral activity.

    PubMed

    Jamin, Augusta; Wicklund, April; Wiebe, Matthew S

    2014-05-01

    Barrier-to-autointegration factor (BAF) is a DNA binding protein with multiple cellular functions, including the ability to act as a potent defense against vaccinia virus infection. This antiviral function involves BAF's ability to condense double-stranded DNA and subsequently prevent viral DNA replication. In recent years, it has become increasingly evident that dynamic phosphorylation involving the vaccinia virus B1 kinase and cellular enzymes is likely a key regulator of multiple BAF functions; however, the precise mechanisms are poorly understood. Here we analyzed how phosphorylation impacts BAF's DNA binding, subcellular localization, dimerization, and antipoxviral activity through the characterization of BAF phosphomimetic and unphosphorylatable mutants. Our studies demonstrate that increased phosphorylation enhances BAF's mobilization from the nucleus to the cytosol, while dephosphorylation restricts BAF to the nucleus. Phosphorylation also impairs both BAF's dimerization and its DNA binding activity. Furthermore, our studies of BAF's antiviral activity revealed that hyperphosphorylated BAF is unable to suppress viral DNA replication or virus production. Interestingly, the unphosphorylatable BAF mutant, which is capable of binding DNA but localizes predominantly to the nucleus, was also incapable of suppressing viral replication. Thus, both DNA binding and localization are important determinants of BAF's antiviral function. Finally, our examination of how phosphatases are involved in regulating BAF revealed that PP2A dephosphorylates BAF during vaccinia infection, thus counterbalancing the activity of the B1 kinase. Altogether, these data demonstrate that phosphoregulation of BAF by viral and cellular enzymes modulates this protein at multiple molecular levels, thus determining its effectiveness as an antiviral factor and likely other functions as well. The barrier-to-autointegration factor (BAF) contributes to cellular genomic integrity in multiple ways, the best characterized of which are as a host defense against cytoplasmic DNA and as a regulator of mitotic nuclear reassembly. Although dynamic phosphorylation involving both viral and cellular enzymes is likely a key regulator of multiple BAF functions, the precise mechanisms involved are poorly understood. Here we demonstrate that phosphorylation coordinately regulates BAF's DNA binding, subcellular localization, dimerization, and antipoxviral activity. Overall, our findings provide new insights into how phosphoregulation of BAF modulates this protein at multiple levels and governs its effectiveness as an antiviral factor against foreign DNA.

  20. Exposure to Pre- and Perinatal Risk Factors Partially Explains Mean Differences in Self-Regulation between Races.

    PubMed

    Barnes, J C; Boutwell, Brian B; Miller, J Mitchell; DeShay, Rashaan A; Beaver, Kevin M; White, Norman

    2016-01-01

    To examine whether differential exposure to pre- and perinatal risk factors explained differences in levels of self-regulation between children of different races (White, Black, Hispanic, Asian, and Other). Multiple regression models based on data from the Early Childhood Longitudinal Study, Birth Cohort (n ≈ 9,850) were used to analyze the impact of pre- and perinatal risk factors on the development of self-regulation at age 2 years. Racial differences in levels of self-regulation were observed. Racial differences were also observed for 9 of the 12 pre-/perinatal risk factors. Multiple regression analyses revealed that a portion of the racial differences in self-regulation was explained by differential exposure to several of the pre-/perinatal risk factors. Specifically, maternal age at childbirth, gestational timing, and the family's socioeconomic status were significantly related to the child's level of self-regulation. These factors accounted for a statistically significant portion of the racial differences observed in self-regulation. The findings indicate racial differences in self-regulation may be, at least partially, explained by racial differences in exposure to pre- and perinatal risk factors.

  1. Frequency of viral infections and environmental factors in multiple sclerosis.

    PubMed

    Eftekharian, Mohammad Mahdi; Ghannad, Masoud Sabouri; Taheri, Mohammad; Roshanaei, Ghodratollah; Mazdeh, Mehrdokht; Musavi, Mehrnoosh; Hormoz, Mona Bahmani

    2016-06-08

    Multiple sclerosis (MS) is a complicated disease which occurs due to relationship between genes and environmental factors that causes tissue damage by autoimmune mechanisms.We investigated and illustrated the hypotheses correlated to the evidence of several putative environmental risk factors for MS onset and progression in this part of Iran. Univariate logistic regression was used to detect the effects of environmental factors on the risk of MS. Data were analyzed using SPSS version 16. The childhood history of patients with rubella, measles and chickenpox increased the risk of MS significantly. Moreover, low consumption of dairy products, avoidance of seafood consumption, cigarette smoking and exposure to tobacco smoke, stress, anxiety disorders, depress and disturbing thoughts, negative and disturbing thoughts, developing a sudden shock upon hearing bad news, having obsessive-compulsive and being depressed increased the risk of MS significantly. The results of the current research partially solved the puzzling question of complex interplay between environmental factors and MS disease in this part of Iran. Incorporating these factors enables more powerful and accurate detection of novel risk factors with diagnostic and prognostic methods.

  2. Downscaling Land Surface Temperature in Complex Regions by Using Multiple Scale Factors with Adaptive Thresholds

    PubMed Central

    Yang, Yingbao; Li, Xiaolong; Pan, Xin; Zhang, Yong; Cao, Chen

    2017-01-01

    Many downscaling algorithms have been proposed to address the issue of coarse-resolution land surface temperature (LST) derived from available satellite-borne sensors. However, few studies have focused on improving LST downscaling in urban areas with several mixed surface types. In this study, LST was downscaled by a multiple linear regression model between LST and multiple scale factors in mixed areas with three or four surface types. The correlation coefficients (CCs) between LST and the scale factors were used to assess the importance of the scale factors within a moving window. CC thresholds determined which factors participated in the fitting of the regression equation. The proposed downscaling approach, which involves an adaptive selection of the scale factors, was evaluated using the LST derived from four Landsat 8 thermal imageries of Nanjing City in different seasons. Results of the visual and quantitative analyses show that the proposed approach achieves relatively satisfactory downscaling results on 11 August, with coefficient of determination and root-mean-square error of 0.87 and 1.13 °C, respectively. Relative to other approaches, our approach shows the similar accuracy and the availability in all seasons. The best (worst) availability occurred in the region of vegetation (water). Thus, the approach is an efficient and reliable LST downscaling method. Future tasks include reliable LST downscaling in challenging regions and the application of our model in middle and low spatial resolutions. PMID:28368301

  3. Potentially Modifiable Factors Associated With Physical Activity in Individuals With Multiple Sclerosis.

    PubMed

    Reider, Nadia; Salter, Amber R; Cutter, Gary R; Tyry, Tuula; Marrie, Ruth Ann

    2017-04-01

    Physical activity levels among persons with multiple sclerosis (MS) are worryingly low. We aimed to identify the factors associated with physical activity for people with MS, with an emphasis on factors that have not been studied previously (bladder and hand dysfunction) and are potentially modifiable. This study was a secondary analysis of data collected in the spring of 2012 during the North American Research Committee on Multiple Sclerosis (NARCOMS) Registry. NARCOMS participants were surveyed regarding smoking using questions from the Behavioral Risk Factor Surveillance Survey; disability using the Patient Determined Disease Steps; fatigue, cognition, spasticity, sensory, bladder, vision and hand function using self-reported Performance Scales; health literacy using the Medical Term Recognition Test; and physical activity using questions from the Health Information National Trends Survey. We used a forward binary logistic regression to develop a predictive model in which physical activity was the outcome variable. Of 8,755 respondents, 1,707 (19.5%) were classified as active and 7,068 (80.5%) as inactive. In logistic regression, being a current smoker, moderate or severe level of disability, depression, fatigue, hand, or bladder dysfunction and minimal to mild spasticity were associated with lower odds of meeting physical activity guidelines. MS type was not linked to activity level. Several modifiable clinical and lifestyle factors influenced physical activity in MS. Prospective studies are needed to evaluate whether modification of these factors can increase physical activity participation in persons with MS. © 2016 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  4. Predictive factors for moderate or severe exacerbations in asthma patients receiving outpatient care.

    PubMed

    Gutiérrez, Francisco Javier Álvarez; Galván, Marta Ferrer; Gallardo, Juan Francisco Medina; Mancera, Marta Barrera; Romero, Beatriz Romero; Falcón, Auxiliadora Romero

    2017-05-02

    Asthma exacerbations are important events that affect disease control, but predictive factors for severe or moderate exacerbations are not known. The objective was to study the predictive factors for moderate (ME) and severe (SE) exacerbations in asthma patients receiving outpatient care. Patients aged > 12 years with asthma were included in the study and followed-up at 4-monthly intervals over a 12-month period. Clinical (severity, level of control, asthma control test [ACT]), atopic, functional, inflammatory, SE and ME parameters were recorded. Univariate analysis was used to compare data from patients presenting at least 1 SE or ME during the follow-up period vs no exacerbations. Statistically significant (p <0.1) factors were then subjected to multiple analysis by binary logistic regression. A total of 330 patients completed the study, most of whom were atopic (76%), women (nearly 70%), with moderate and mild persistent asthma (>80%). Twenty-seven patients (8%) had a SE and 183 had a ME (58.5%) during follow-up. In the case of SEs, the only predictive factor identified in the multiple analysis was previous SE (baseline visit OR 4.218 95% CI 1.53-11.58, 4-month follow-up OR 6.88 95% CI 2.018-23.51) and inhalation technique (OR 3.572 95% CI 1.324-9.638). In the case of MEs, the only predictive factor found in the multiple analysis were previous ME (baseline visit OR 2.90 95% CI 1.54-5.48, 4-month follow- up OR 1.702 95% CI 1.146-2.529). The primary predictive factor for SE or ME is prior SE or ME, respectively. SEs seem to constitute a specific patient "phenotype", in which the sole predictive factor is prior SEs.

  5. Normalisation theory: Does it accurately describe temporal changes in adolescent drunkenness and smoking?

    PubMed

    Sznitman, Sharon R; Zlotnick, Cheryl; Harel-Fisch, Yossi

    2016-07-01

    The multiple risk model postulates that accumulating risk factors increase adolescent drunkenness and smoking. The normalisation theory adds to this by arguing that the relation between accumulative risk and drunkenness and smoking is dependent on the distribution of these behaviours in the larger population. More concretely, normalisation theory predicts that: (i) when population level use increases, low risk adolescents will be more likely to use alcohol and cigarettes; and (ii) adolescents facing multiple risk factors will be equally likely to use alcohol and cigarettes, regardless of trends in population level use. The current study empirically tests these assumptions on five waves of nationally representative samples of Israeli Jewish youth. Five cross-sectional waves of data from the Israeli Health Behaviour in School-aged Children survey for Jewish 10th graders were used. Logistic regression models measured the impact of changes in population level use across waves on drunkenness and smoking, and their association with differing levels of risk factors. Between zero and two risk factors, the risk of drunkenness and smoking increases for each additional risk factor. When reaching two risk factors, added risk does not significantly increase the likelihood of smoking and drunkenness. Changes in population level drunkenness and smoking did not systematically relate to changes in the individual level relationship between risk factors and smoking and drunkenness. The pattern of results in this study provides strong evidence for the multiple risk factor model and inconsistent evidence for the normalisation theory. [Sznitman SR, Zlotnick C, Harel-Fisch Y. Normalisation theory: Does it accurately describe temporal changes in adolescent drunkenness and smoking? Drug Alcohol Rev 2016;35:424-432]. © 2015 Australasian Professional Society on Alcohol and other Drugs.

  6. Knowledge, attitude and practices of women in maldives related to the risk factors, prevention and early detection of cervical cancer.

    PubMed

    Basu, Partha; Hassan, Salma; Fileeshia, Fathmath; Mohamed, Sizna; Nahoodha, Aminath; Shiuna, Aminath; Sulaiman, Asma Ibrahim; Najeeb, Nazeera; Saleem, Fathmath Jeehan

    2014-01-01

    A population-based cervical cancer screening program using visual inspection with acetic acid was launched in Maldives in 2014. Our study aimed to assess the knowledge, attitude and practices of women in relation to risk factors of cervical cancer, early detection of the disease and its prevention. The questionnaire based survey was conducted among 20 to 50 year old women, systematically sampled to represent three regions of Maldives. Trained investigators interviewed a total of 2,845 women at home. The prevalence of the risk factors of cervical cancer like early age at marriage and childbirth, multiple marriages, multiple marriages of the husbands, and multiple pregnancies was high. More women knew about breast cancer than cervical cancer. Even among the small number of women who knew of cervical cancer, only 34.6% had the knowledge of at least one early symptom. Very few women knew that the cancer could be prevented by any test. Only 6.2% of the women reported having ever undergone a Pap smear. Many women had the misconception that cervical cancer was infectious. In Maldives the younger women have high literacy rate due to the policy of universal free education and those with higher levels of education had improved knowledge of cervical cancer and its risk factors. The prevalence of risk factors also reduced with improved literacy. Awareness about risk factors and prevention of cervical cancer is limited among Maldivian women in spite of having high exposure to some of the risk factors. A universal literacy program in the country has helped to improve the knowledge of cervical cancer prevention and to reduce the exposure to various risk factors in the younger population.

  7. Sociodemographic factors associated with multiple cardiovascular risk factors among Malaysian adults.

    PubMed

    Ghazali, Sumarni Mohd; Seman, Zamtira; Cheong, Kee Chee; Hock, Lim Kuang; Manickam, Mala; Kuay, Lim Kuang; Yusoff, Ahmad Faudzi; Mustafa, Feisul Idzwan; Mustafa, Amal Nasir

    2015-01-31

    To determine the prevalence and sociodemographic correlates of multiple risk factors for cardiovascular disease (CVD) among Malaysian adults. We analysed data on 1044 men and 1528 women, aged 24-64 years, participants in the Non Communicable Disease Surveillance 2005/2006, a nationally representative, population-based, cross-sectional study. Prevalence of obesity, high blood pressure, dyslipidaemia, hyperglycemia, physical inactivity, smoking, risky drinking, low vegetable and fruit intake were determined and multivariable logistic regression was used to identify sociodemographic factors associated with having ≥3 of these cardiovascular disease risk factors. The response rate was 84.6% (2572/3040). Overall, 68.4% (95% CI: 63.2, 73.1) had at least three risk factors. Among men, older age and Indian ethnicity were independently associated with having ≥3 CVD risk factors; while among women, older age, low education, and housewives were more likely to have ≥3 CVD risk factors. The prevalence of cardiovascular risk factors clustering among Malaysian adults is high, raising concerns that cardiovascular disease incidence will rise steeply in the near future if no immediate preventive measures are taken. The current national health education and promotion programmes pertaining to modifiable risk factors can be further improved by taking into account the sociodemographic variation in CVD risk factors clustering.

  8. Circadian Enhancers Coordinate Multiple Phases of Rhythmic Gene Transcription In Vivo

    PubMed Central

    Fang, Bin; Everett, Logan J.; Jager, Jennifer; Briggs, Erika; Armour, Sean M.; Feng, Dan; Roy, Ankur; Gerhart-Hines, Zachary; Sun, Zheng; Lazar, Mitchell A.

    2014-01-01

    SUMMARY Mammalian transcriptomes display complex circadian rhythms with multiple phases of gene expression that cannot be accounted for by current models of the molecular clock. We have determined the underlying mechanisms by measuring nascent RNA transcription around the clock in mouse liver. Unbiased examination of eRNAs that cluster in specific circadian phases identified functional enhancers driven by distinct transcription factors (TFs). We further identify on a global scale the components of the TF cistromes that function to orchestrate circadian gene expression. Integrated genomic analyses also revealed novel mechanisms by which a single circadian factor controls opposing transcriptional phases. These findings shed new light on the diversity and specificity of TF function in the generation of multiple phases of circadian gene transcription in a mammalian organ. PMID:25416951

  9. Treatment of multiple-risk patients: using combination therapy to treat beyond LDL lowering.

    PubMed

    Weintraub, Howard S

    2005-08-01

    During the past 25 years, the role of traditional "risk factors" in the genesis of atherosclerotic vascular disease has been convincingly validated. The impact of elevated low-density lipoprotein cholesterol, hypertension, type II diabetes, and metabolic syndrome are now well accepted. However, until recently, there was guilt by association without a clear understanding of the manner in which the crime was committed. It is now acknowledged that the presence of multiple risk factors can increase the likelihood of an ischemic event. This has become a great concern, given the very high prevalence of patients who fall into this category. In light of this information, the mandate for appropriate guideline-driven therapy has become even stronger, and we must consider the use of multiple medications to effectively neutralize this risk.

  10. Circadian enhancers coordinate multiple phases of rhythmic gene transcription in vivo.

    PubMed

    Fang, Bin; Everett, Logan J; Jager, Jennifer; Briggs, Erika; Armour, Sean M; Feng, Dan; Roy, Ankur; Gerhart-Hines, Zachary; Sun, Zheng; Lazar, Mitchell A

    2014-11-20

    Mammalian transcriptomes display complex circadian rhythms with multiple phases of gene expression that cannot be accounted for by current models of the molecular clock. We have determined the underlying mechanisms by measuring nascent RNA transcription around the clock in mouse liver. Unbiased examination of enhancer RNAs (eRNAs) that cluster in specific circadian phases identified functional enhancers driven by distinct transcription factors (TFs). We further identify on a global scale the components of the TF cistromes that function to orchestrate circadian gene expression. Integrated genomic analyses also revealed mechanisms by which a single circadian factor controls opposing transcriptional phases. These findings shed light on the diversity and specificity of TF function in the generation of multiple phases of circadian gene transcription in a mammalian organ.

  11. Tidal Channel Diatom Assemblages Reflect within Wetland Environmental Conditions and Land Use at Multiple Scales

    EPA Science Inventory

    We characterized regional patterns of the tidal channel benthic diatom community and examined the relative importance of local wetland and surrounding landscape level factors measured at multiple scales in structuring this assemblage. Surrounding land cover was characterized at ...

  12. Biomaterial delivery of morphogens to mimic the natural healing cascade in bone.

    PubMed

    Mehta, Manav; Schmidt-Bleek, Katharina; Duda, Georg N; Mooney, David J

    2012-09-01

    Complications in treatment of large bone defects using bone grafting still remain. Our understanding of the endogenous bone regeneration cascade has inspired the exploration of a wide variety of growth factors (GFs) in an effort to mimic the natural signaling that controls bone healing. Biomaterial-based delivery of single exogenous GFs has shown therapeutic efficacy, and this likely relates to its ability to recruit and promote replication of cells involved in tissue development and the healing process. However, as the natural bone healing cascade involves the action of multiple factors, each acting in a specific spatiotemporal pattern, strategies aiming to mimic the critical aspects of this process will likely benefit from the usage of multiple therapeutic agents. This article reviews the current status of approaches to deliver single GFs, as well as ongoing efforts to develop sophisticated delivery platforms to deliver multiple lineage-directing morphogens (multiple GFs) during bone healing. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. The combination of energy-dependent internal adaptation mechanisms and external factors enables Listeria monocytogenes to express a strong starvation survival response during multiple-nutrient starvation.

    PubMed

    Lungu, Bwalya; Saldivar, Joshua C; Story, Robert; Ricke, Steven C; Johnson, Michael G

    2010-05-01

    The goal of this study was to characterize the starvation survival response (SSR) of a wild-type Listeria monocytogenes 10403S and an isogenic DeltasigB mutant strain during multiple-nutrient starvation conditions over 28 days. This study examined the effects of inhibitors of protein synthesis, the proton motive force, substrate level phosphorylation, and oxidative phosphorylation on the SSR of L. monocytogenes 10403S and a DeltasigB mutant during multiple-nutrient starvation. The effects of starvation buffer changes on viability were also examined. During multiple-nutrient starvation, both strains expressed a strong SSR, suggesting that L. monocytogenes possesses SigB-independent mechanism(s) for survival during multiple-nutrient starvation. Neither strain was able to express an SSR following starvation buffer changes, indicating that the nutrients/factors present in the starvation buffer could be a source of energy for cell maintenance and survival. Neither the wild-type nor the DeltasigB mutant strain was able to elicit an SSR when exposed to the protein synthesis inhibitor chloramphenicol within the first 4 h of starvation. However, both strains expressed an SSR when exposed to chloramphenicol after 6 h or more of starvation, suggesting that the majority of proteins required to elicit an effective SSR in L. monocytogenes are likely produced somewhere between 4 and 6 h of starvation. The varying SSRs of both strains to the different metabolic inhibitors under aerobic or anaerobic conditions suggested that (1) energy derived from the proton motive force is important for an effective SSR, (2) L. monocytogenes utilizes an anaerobic electron transport during multiple-nutrient starvation conditions, and (3) the glycolytic pathway is an important energy source during multiple-nutrient starvation when oxygen is available, and less important under anaerobic conditions. Collectively, the data suggest that the combination of energy-dependent internal adaptation mechanisms of cells and external nutrients/factors enables L. monocytogenes to express a strong SSR.

  14. A Contextual Factors Framework to Inform Implementation and Evaluation of Public Health Initiatives

    ERIC Educational Resources Information Center

    Vanderkruik, Rachel; McPherson, Marianne E.

    2017-01-01

    Evaluating initiatives implemented across multiple settings can elucidate how various contextual factors may influence both implementation and outcomes. Understanding context is especially critical when the same program has varying levels of success across settings. We present a framework for evaluating contextual factors affecting an initiative…

  15. Measurement and Structural Model Class Separation in Mixture CFA: ML/EM versus MCMC

    ERIC Educational Resources Information Center

    Depaoli, Sarah

    2012-01-01

    Parameter recovery was assessed within mixture confirmatory factor analysis across multiple estimator conditions under different simulated levels of mixture class separation. Mixture class separation was defined in the measurement model (through factor loadings) and the structural model (through factor variances). Maximum likelihood (ML) via the…

  16. Highway safety : factors contributing to traffic crashes and NHTSA's efforts to address them : statement of Peter Guerrero, Director, Physical Infrastructure Issues

    DOT National Transportation Integrated Search

    2003-05-22

    Most motor vehicle crashes have multiple causes. Experts and studies have identified three categories of factors that contribute to crashes-human, roadway environment, and vehicle factors. From 1975 through 2002, the rate of fatalities per 100 millio...

  17. An integrative model links multiple inputs and signaling pathways to the onset of DNA synthesis in hepatocytes

    PubMed Central

    Huard, Jérémy; Mueller, Stephanie; Gilles, Ernst D; Klingmüller, Ursula; Klamt, Steffen

    2012-01-01

    During liver regeneration, quiescent hepatocytes re-enter the cell cycle to proliferate and compensate for lost tissue. Multiple signals including hepatocyte growth factor, epidermal growth factor, tumor necrosis factor α, interleukin-6, insulin and transforming growth factor β orchestrate these responses and are integrated during the G1 phase of the cell cycle. To investigate how these inputs influence DNA synthesis as a measure for proliferation, we established a large-scale integrated logical model connecting multiple signaling pathways and the cell cycle. We constructed our model based upon established literature knowledge, and successively improved and validated its structure using hepatocyte-specific literature as well as experimental DNA synthesis data. Model analyses showed that activation of the mitogen-activated protein kinase and phosphatidylinositol 3-kinase pathways was sufficient and necessary for triggering DNA synthesis. In addition, we identified key species in these pathways that mediate DNA replication. Our model predicted oncogenic mutations that were compared with the COSMIC database, and proposed intervention targets to block hepatocyte growth factor-induced DNA synthesis, which we validated experimentally. Our integrative approach demonstrates that, despite the complexity and size of the underlying interlaced network, logical modeling enables an integrative understanding of signaling-controlled proliferation at the cellular level, and thus can provide intervention strategies for distinct perturbation scenarios at various regulatory levels. PMID:22443451

  18. Multidimensional Predictors of Fatigue among Octogenarians and Centenarians

    PubMed Central

    Cho, Jinmyoung; Martin, Peter; Margrett, Jennifer; MacDonald, Maurice; Johnson, Mary Ann; Poon, Leonard W.

    2012-01-01

    Background Fatigue is a common and frequently observed complaint among older adults. However, knowledge about the nature and correlates of fatigue in old age is very limited. Objective: This study examined the relationship of functional indicators, psychological and situational factors and fatigue for 210 octogenarians and centenarians from the Georgia Centenarian Study. Methods Three indicators of functional capacity (self-rated health, instrumental activities of daily living, physical activities of daily living), two indicators of psychological well-being (positive and negative affect), two indicators of situational factors (social network and social support), and a multidimensional fatigue scale were used. Blocked multiple regression analyses were computed to examine significant factors related to fatigue. In addition, multi-group analysis in structural equation modeling was used to investigate residential differences (i.e., long-term care facilities vs. private homes) in the relationship between significant factors and fatigue. Results Blocked multiple regression analyses indicated that two indicators of functional capacity, self-rated health and instrumental activities of daily living, both positive and negative affect, and social support were significant predictors of fatigue among oldest-old adults. The multiple group analysis in structural equation modeling revealed a significant difference among oldest-old adults based on residential status. Conclusion The results suggest that we should not consider fatigue as merely an unpleasant physical symptom, but rather adopt a perspective that different factors such as psychosocial aspects can influence fatigue in advanced later life. PMID:22094445

  19. Multidimensional predictors of fatigue among octogenarians and centenarians.

    PubMed

    Cho, Jinmyoung; Martin, Peter; Margrett, Jennifer; MacDonald, Maurice; Johnson, Mary Ann; Poon, Leonard W; Jazwinski, S M; Green, R C; Gearing, M; Woodard, J L; Tenover, J S; Siegler, I C; Rott, C; Rodgers, W L; Hausman, D; Arnold, J; Davey, A

    2012-01-01

    Fatigue is a common and frequently observed complaint among older adults. However, knowledge about the nature and correlates of fatigue in old age is very limited. This study examined the relationship of functional indicators, psychological and situational factors and fatigue for 210 octogenarians and centenarians from the Georgia Centenarian Study. Three indicators of functional capacity (self-rated health, instrumental activities of daily living, physical activities of daily living), two indicators of psychological well-being (positive and negative affect), two indicators of situational factors (social network and social support), and a multidimensional fatigue scale were used. Blocked multiple regression analyses were computed to examine significant factors related to fatigue. In addition, multi-group analysis in structural equation modeling was used to investigate residential differences (i.e., long-term care facilities vs. private homes) in the relationship between significant factors and fatigue. Blocked multiple regression analyses indicated that two indicators of functional capacity, self-rated health and instrumental activities of daily living, both positive and negative affect, and social support were significant predictors of fatigue among oldest-old adults. The multiple group analysis in structural equation modeling revealed a significant difference among oldest-old adults based on residential status. The results suggest that we should not consider fatigue as merely an unpleasant physical symptom, but rather adopt a perspective that different factors such as psychosocial aspects can influence fatigue in advanced later life. Copyright © 2011 S. Karger AG, Basel.

  20. What Is the Prevalence of Symptomatic Obstructive Sleep Apnea Syndrome in Chronic Spinal Pain Patients? An Assessment of the Correlation of OSAS with Chronic Opioid Therapy, Obesity, and Smoking.

    PubMed

    Pampati, Sanjana; Manchikanti, Laxmaiah

    2016-05-01

    In modern medicine, obstructive sleep apnea syndrome (OSAS) is a commonly described sleep disorder with airway obstruction, disrupted sleep, and excessive daytime sleepiness. Since its description in 1976 by Guilleminault et al, numerous epidemiologic studies and systematic reviews, with multiple comorbidities related to cardiovascular sequelae, altered cognitive function, and multiple other potential complications have been described. Multiple risk factors have been identified included obesity, smoking, alcohol consumption, and other factors. Chronic pain and chronic opioid therapy also have been described to contribute to a large proportion of patients with OSAS. Chronic pain, obesity, smoking, and chronic opioid therapy are often found together, yet there is a paucity of literature describing OSAS in chronic pain patients. To assess the prevalence of symptomatic OSAS in chronic spinal pain patients receiving chronic opioid therapy and determine the association of OSAS with multiple risk factors and comorbidities. A retrospective assessment of patients who attend a single interventional pain management practice from January 1, 2010to December 31, 2014. A private interventional pain management practice in the United States. The data were collected from 4,036 consecutive patients presenting for assessment to a pain management center from January 1, 2010 to December 31, 2014. All assessments were comprehensive and performed by 2 physicians. The comprehensive assessment included a complete history, a physical examination, and a review of records. The prevalence of OSAS in patients with chronic spinal pain was 13.8%. The results showed a higher prevalence in males compared to females (15.1% versus 12.8%), a higher prevalence in those aged 45 or older compared to those 25-45 years and those 18-25 years (16.3% versus 10.7% or 2.5%), higher prevalence in Hispanics and Asians compared to African Americans and whites (23.7% versus 16.2% versus 13.4%), higher prevalence in patients with combined back and neck pain compared to patients with thoracic pain only or back pain only (16.3% versus 8.2% to 11%). Prevalence also varied by body mass index (BMI): 32.4% in morbidly obese patients, 20.3% in severely obese patients, 15.7% in obese patients, 9.2% in those who were overweight, and only 5.7% in those with normal weight. A significant correlation with OSAS was also observed in patients smoking more than 40 pack years and multiple respiratory symptoms except for chronic bronchitis and multiple cardiovascular ailments. The retrospective nature of the assessment. This retrospective assessment of over 4,000 patients suffering from chronic pain and receiving chronic opioid therapy indicated a prevalence of sleep apnea syndrome as 13.8%. Multiple risk factors including obesity, chronic obstructive pulmonary disease (COPD), chronic sinus and nasal discharge, and multiple comorbidities including cardiovascular and related ailments have been identified. Obstructive sleep apnea syndrome, chronic pain, chronic spinal pain, chronic opioid therapy, obesity, smoking, cardiovascular risk factors, pulmonary risk factors.

  1. Optimization and development of stable w/o/w cosmetic multiple emulsions by means of the Quality by Design approach.

    PubMed

    Kovács, A; Erős, I; Csóka, I

    2016-04-01

    The aim of our present work was to develop stable water-in-oil-in-water (w/o/w) cosmetic multiple emulsions that are proper for cosmetic use and can also be applied on the skin as pharmaceutical vehicles by means of Quality by Design (QbD) concept. This product design concept consists of a risk assessment step and also the 'predetermination' of the critical material attributes and process parameters of a stable multiple emulsion system. We have set up the hypothesis that the stability of multiple emulsions can be improved by the development based on such systematic planning - making a map of critical product parameters - so their industrial usage can be increased. The risk assessment and the determination of critical physical-chemical stability parameters of w/o/w multiple emulsions to define critical control points were performed by means of quality tools and the leanqbd(™) (QbD Works LLC, Fremont, CA, U.S.A.) software. Critical materials and process parameters: Based on the results of preformulation experiments, three factors, namely entrapped active agent, preparation methodology and shear rate, were found to be highly critical factors for critical quality attributes (CQAs) and for stability, whereas the nature of oil was found a medium level risk factor. The results of the risk assessment are the following: (i) droplet structure and size distribution should be evaluated together to be able to predict the stability issues, (ii) the presence of entrapped active agents had a great impact on droplet structure, (iii) the viscosity curves represent the structural changes during storage, if the decrease in relative viscosity is >15% the emulsion disintegrates, and (iv) it is enough to use the shear rate between 34g and 116g relative centrifugal force (RCF). CQAs: By risk assessment, we discovered that four factors should be considered to be high-risk variables as compared to others: droplet size, droplet structure, viscosity and multiple character were found to be highly critical attributes. The preformulation experiment is the part of a development plan. On the basis of these results, the control strategy can be defined and a stable multiple emulsion can be ensured that meets the relevant stakeholders' quality expectations. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  2. Prevalence of upper gastrointestinal bleeding risk factors among the general population and osteoarthritis patients.

    PubMed

    Kim, Sang Hyuck; Yun, Jae Moon; Chang, Chong Bum; Piao, Heng; Yu, Su Jong; Shin, Dong Wook

    2016-12-28

    To assess the prevalence of possible risk factors of upper gastrointestinal bleeding (UGIB) and their age-group specific trend among the general population and osteoarthritis patients. We utilized data from the National Health Insurance Service that included claims data and results of the national health check-up program. Comorbid conditions (peptic ulcer, diabetes, liver disease, chronic renal failure, and gastroesophageal reflux disease), concomitant drugs (aspirin, clopidogrel, cilostazol, non-steroidal anti-inflammatory drugs, steroid, anticoagulants, and SSRI), personal habits (smoking, and alcohol consumption) were considered as possible UGIB risk factors. We randomly imputed the prevalence of infection in the data considering the age-specific prevalence of Helicobacter pylori ( H. pylori ) infection in Korea. The prevalence of various UGIB risk factors and the age-group specific trend of the prevalence were identified. Prevalence was compared between osteoarthritis patients and others. A total of 801926 subjects (93855 osteoarthritis patients) aged 20 and above were included. The prevalence of individual and concurrent multiple risk factors became higher as the age increased. The prevalence of each comorbid condition and concomitant drug were higher in osteoarthritis patients. Thirty-five point zero two percent of the overall population and 68.50% of osteoarthritis patients had at least one or more risk factors of UGIB. The prevalence of individual and concurrent multiple risk factors in younger age groups were also substantial. Furthermore, when personal habits (smoking, and alcohol consumption) and H. pylori infection were included, the prevalence of concurrent multiple risk factors increased greatly even in younger age groups. Prevalence of UGIB risk factors was high in elderly population, but was also considerable in younger population. Patient with osteoarthritis was at higher UGIB risk than those without osteoarthritis. Physicians should consider individualized risk assessment regardless of age when prescribing drugs or performing procedures that may increase the risk of UGIB, and take necessary measures to reduce modifiable risk factors such as H. pylori eradication or lifestyle counseling.

  3. The Development and Validation of the Protective Factors Survey: A Self-Report Measure of Protective Factors against Child Maltreatment

    ERIC Educational Resources Information Center

    Counts, Jacqueline M.; Buffington, Elenor S.; Chang-Rios, Karin; Rasmussen, Heather N.; Preacher, Kristopher J.

    2010-01-01

    Objective: The objective of this study was to evaluate the internal structure of a self-report measure of multiple family-level protective factors against abuse and neglect and explore the relationship of this instrument to other measures of child maltreatment. Methods: For the exploratory factor analysis, 11 agencies from 4 states administered…

  4. USING DOSE ADDITION TO ESTIMATE CUMULATIVE RISKS FROM EXPOSURES TO MULTIPLE CHEMICALS

    EPA Science Inventory

    The Food Quality Protection Act (FQPA) of 1996 requires the EPA to consider the cumulative risk from exposure to multiple chemicals that have a common mechanism of toxicity. Three methods, hazard index (HI), point-of-departure index (PODI), and toxicity equivalence factor (TEF), ...

  5. In anemia of multiple myeloma hepcidin is induced by increased bone-morphogenetic protein-2

    USDA-ARS?s Scientific Manuscript database

    Hepcidin is the principal iron-regulatory hormone and pathogenic factor in anemia of inflammation. Patients with multiple myeloma (MM) frequently present with anemia. We showed that MM patients had increased serum hepcidin, which inversely correlated with hemoglobin, suggesting that hepcidin contrib...

  6. Determinants of Employment Status among People with Multiple Sclerosis.

    ERIC Educational Resources Information Center

    Roessler, Richard T.; Fitzgerald, Shawn M.; Rumrill, Phillip D.; Koch, Lynn C.

    2001-01-01

    Identifies factors predicting employment or lack thereof among adults with multiple sclerosis (MS). Results included the following variables as the best predictors of employment: symptom persistence, severity of symptoms, educational attainment, and presence of cognitive limitations. The relevance of the findings for rehabilitation assessment and…

  7. Is there a genetic solution to bovine respiratory disease complex?

    USDA-ARS?s Scientific Manuscript database

    Bovine respiratory disease complex (BRDC) is a complex multi-factor disease, which increases costs and reduces revenue from feedlot cattle. Multiple stressors and pathogens (viral and bacterial) have been implicated in the etiology of BRDC, therefore multiple approaches will be needed to evaluate a...

  8. Bayesian rationality in evaluating multiple testimonies: incorporating the role of coherence.

    PubMed

    Harris, Adam J L; Hahn, Ulrike

    2009-09-01

    Routinely in day-to-day life, as well as in formal settings such as the courtroom, people must aggregate information they receive from different sources. One intuitively important but underresearched factor in this context is the degree to which the reports from different sources fit together, that is, their coherence. The authors examine a version of Bayes' theorem that not only includes factors such as prior beliefs and witness reliability, as do other models of information aggregation, but also makes transparent the effect of the coherence of multiple testimonies on the believability of the information. The results suggest that participants are sensitive to all the normatively relevant factors when assessing the believability of a set of witness testimonies. (c) 2009 APA, all rights reserved.

  9. Adherence to multiple micronutrient powders and associated factors in children aged 6 to 35 months treated in sentinel health facilities, Ministry of Health of Peru.

    PubMed

    Munares-García, Oscar; Gómez-Guizado, Guillermo

    2016-01-01

    Anemia in children is a public health issue, and the current strategies include treatment and iron supplementation, but their level of adherence or compliance is unknown. To consider the adherence to multiple micronutrient powders and the associated factors. Epidemiological study of active surveillance through sentinel facilities in 2,024 children aged 6 to 35 months treated in health facilities of the Ministry of Health of Peru, from October to December 2014. Household visits were conducted in which counting of multiple micronutrient powders was applied and determined an adherence of consumption ≥ 90% envelopes, besides a form on the associated factors (anemia knowledge, iron-rich food, side effects, dosage regimen, drugs used, and motivation) was applied. Descriptive statistics, χ² test, Odds Ratio with a 95% confidence interval (CI), and binary logistic regression or adjusted Odds Ratio (aOR) were used. Of all, 79.1% participants were aged 6 to 23 months; 75.9% received multiple micronutrient powders; and the adherence was equivalent to 24.4% (95%CI 22.3 - 26.6). The factors: continue supplementation (OR = 3.5; 95%CI 1.7 - 7.5); no nausea (OR = 3.0; 95%CI 2.0 - 4.3); no use of antibiotics (OR = 2.5; 95%CI 1.7 - 3.6); and intention to continue treatment (OR = 2.3; 95%CI 1.3 - 4.1) were associated with adherence. The variables: thought of continuing treatment (aOR = 2.6; 95%CI 1.1 - 6.1); presence of side effects, but no discontinuation of the treatment (aOR = 2.5; 95%CI 1.4 - 4.3); no use of antibiotics (aOR = 2.0; 95%CI 1.1 - 3.4); and belief that not only drugs cure anemia (aOR = 1.6; 95%CI 1.0 - 2.6) were associated in the multivariate analysis. There was a low prevalence of adherence to a demanding cut-off point (≥ 90% of envelopes of multiple micronutrient powders), and the associated factors are associated with absence of infections, side effects, and mother's beliefs.

  10. Quantifying drivers of wild pig movement across multiple spatial and temporal scales.

    PubMed

    Kay, Shannon L; Fischer, Justin W; Monaghan, Andrew J; Beasley, James C; Boughton, Raoul; Campbell, Tyler A; Cooper, Susan M; Ditchkoff, Stephen S; Hartley, Steve B; Kilgo, John C; Wisely, Samantha M; Wyckoff, A Christy; VerCauteren, Kurt C; Pepin, Kim M

    2017-01-01

    The movement behavior of an animal is determined by extrinsic and intrinsic factors that operate at multiple spatio-temporal scales, yet much of our knowledge of animal movement comes from studies that examine only one or two scales concurrently. Understanding the drivers of animal movement across multiple scales is crucial for understanding the fundamentals of movement ecology, predicting changes in distribution, describing disease dynamics, and identifying efficient methods of wildlife conservation and management. We obtained over 400,000 GPS locations of wild pigs from 13 different studies spanning six states in southern U.S.A., and quantified movement rates and home range size within a single analytical framework. We used a generalized additive mixed model framework to quantify the effects of five broad predictor categories on movement: individual-level attributes, geographic factors, landscape attributes, meteorological conditions, and temporal variables. We examined effects of predictors across three temporal scales: daily, monthly, and using all data during the study period. We considered both local environmental factors such as daily weather data and distance to various resources on the landscape, as well as factors acting at a broader spatial scale such as ecoregion and season. We found meteorological variables (temperature and pressure), landscape features (distance to water sources), a broad-scale geographic factor (ecoregion), and individual-level characteristics (sex-age class), drove wild pig movement across all scales, but both the magnitude and shape of covariate relationships to movement differed across temporal scales. The analytical framework we present can be used to assess movement patterns arising from multiple data sources for a range of species while accounting for spatio-temporal correlations. Our analyses show the magnitude by which reaction norms can change based on the temporal scale of response data, illustrating the importance of appropriately defining temporal scales of both the movement response and covariates depending on the intended implications of research (e.g., predicting effects of movement due to climate change versus planning local-scale management). We argue that consideration of multiple spatial scales within the same framework (rather than comparing across separate studies post-hoc ) gives a more accurate quantification of cross-scale spatial effects by appropriately accounting for error correlation.

  11. Inhibiting poly(ADP-ribose) polymerase: a potential therapy against oligodendrocyte death

    PubMed Central

    Veto, Sara; Acs, Peter; Bauer, Jan; Lassmann, Hans; Berente, Zoltan; Setalo, Gyorgy; Borgulya, Gabor; Sumegi, Balazs; Komoly, Samuel; Gallyas, Ferenc; Illes, Zsolt

    2010-01-01

    Oligodendrocyte loss and demyelination are major pathological hallmarks of multiple sclerosis. In pattern III lesions, inflammation is minor in the early stages, and oligodendrocyte apoptosis prevails, which appears to be mediated at least in part through mitochondrial injury. Here, we demonstrate poly(ADP-ribose) polymerase activation and apoptosis inducing factor nuclear translocation within apoptotic oligodendrocytes in such multiple sclerosis lesions. The same morphological and molecular pathology was observed in an experimental model of primary demyelination, induced by the mitochondrial toxin cuprizone. Inhibition of poly(ADP-ribose) polymerase in this model attenuated oligodendrocyte depletion and decreased demyelination. Poly(ADP-ribose) polymerase inhibition suppressed c-Jun N-terminal kinase and p38 mitogen-activated protein kinase phosphorylation, increased the activation of the cytoprotective phosphatidylinositol-3 kinase-Akt pathway and prevented caspase-independent apoptosis inducing factor-mediated apoptosis. Our data indicate that poly(ADP-ribose) polymerase activation plays a crucial role in the pathogenesis of pattern III multiple sclerosis lesions. Since poly(ADP-ribose) polymerase inhibition was also effective in the inflammatory model of multiple sclerosis, it may target all subtypes of multiple sclerosis, either by preventing oligodendrocyte death or attenuating inflammation. PMID:20157013

  12. Action of multiple intra-QTL genes concerted around a co-localized transcription factor underpins a large effect QTL

    PubMed Central

    Dixit, Shalabh; Kumar Biswal, Akshaya; Min, Aye; Henry, Amelia; Oane, Rowena H.; Raorane, Manish L.; Longkumer, Toshisangba; Pabuayon, Isaiah M.; Mutte, Sumanth K.; Vardarajan, Adithi R.; Miro, Berta; Govindan, Ganesan; Albano-Enriquez, Blesilda; Pueffeld, Mandy; Sreenivasulu, Nese; Slamet-Loedin, Inez; Sundarvelpandian, Kalaipandian; Tsai, Yuan-Ching; Raghuvanshi, Saurabh; Hsing, Yue-Ie C.; Kumar, Arvind; Kohli, Ajay

    2015-01-01

    Sub-QTLs and multiple intra-QTL genes are hypothesized to underpin large-effect QTLs. Known QTLs over gene families, biosynthetic pathways or certain traits represent functional gene-clusters of genes of the same gene ontology (GO). Gene-clusters containing genes of different GO have not been elaborated, except in silico as coexpressed genes within QTLs. Here we demonstrate the requirement of multiple intra-QTL genes for the full impact of QTL qDTY12.1 on rice yield under drought. Multiple evidences are presented for the need of the transcription factor ‘no apical meristem’ (OsNAM12.1) and its co-localized target genes of separate GO categories for qDTY12.1 function, raising a regulon-like model of genetic architecture. The molecular underpinnings of qDTY12.1 support its effectiveness in further improving a drought tolerant genotype and for its validity in multiple genotypes/ecosystems/environments. Resolving the combinatorial value of OsNAM12.1 with individual intra-QTL genes notwithstanding, identification and analyses of qDTY12.1has fast-tracked rice improvement towards food security. PMID:26507552

  13. Adjustable repetition-rate multiplication of optical pulses using fractional temporal Talbot effect with preceded binary intensity modulation

    NASA Astrophysics Data System (ADS)

    Xie, Qijie; Zheng, Bofang; Shu, Chester

    2017-05-01

    We demonstrate a simple approach for adjustable multiplication of optical pulses in a fiber using the temporal Talbot effect. Binary electrical patterns are used to control the multiplication factor in our approach. The input 10 GHz picosecond pulses are pedestal-free and are shaped directly from a CW laser. The pulses are then intensity modulated by different sets of binary patterns prior to entering a fiber of fixed dispersion. Tunable repetition-rate multiplication by different factors of 2, 4, and 8 have been achieved and up to 80 GHz pulse train has been experimentally generated. We also evaluate numerically the influence of the extinction ratio of the intensity modulator on the performance of the multiplied pulse train. In addition, the impact of the modulator bias on the uniformity of the output pulses has also been analyzed through simulation and experiment and a good agreement is reached. Last, we perform numerical simulation on the RF spectral characteristics of the output pulses. The insensitivity of the signal-to-subharmonic noise ratio (SSNR) to the laser linewidth shows that our multiplication scheme is highly tolerant to the incoherence of the input optical pulses.

  14. Disease Modifying Therapy in Multiple Sclerosis

    PubMed Central

    Williams, U. E.; Oparah, S. K.; Philip-Ephraim, E. E.

    2014-01-01

    Multiple sclerosis is an autoimmune disease of the central nervous system characterized by inflammatory demyelination and axonal degeneration. It is the commonest cause of permanent disability in young adults. Environmental and genetic factors have been suggested in its etiology. Currently available disease modifying drugs are only effective in controlling inflammation but not prevention of neurodegeneration or accumulation of disability. Search for an effective neuroprotective therapy is at the forefront of multiple sclerosis research. PMID:27355035

  15. Falls in multiple sclerosis.

    PubMed

    Matsuda, Patricia N; Shumway-Cook, Anne; Bamer, Alyssa M; Johnson, Shana L; Amtmann, Dagmar; Kraft, George H

    2011-07-01

    To examine incidence, associated factors, and health care provider (HCP) response to falls in persons with multiple sclerosis (MS). Cross-sectional retrospective design. Community setting. Four hundred seventy-four persons with MS. Mailed survey questionnaire examined incidence, risk factors, and HCP response to falls in persons with MS who were dwelling in the community. Univariate and multiple ordinal regression analysis identified variables associated with single and multiple falls. Falls, causes and perceived reasons for falls, and HCP response. A total of 265 participants (58.2%) reported one or more falls in the previous 6 months, and 58.5% of falls were medically injurious. Trips/slips while walking accounted for 48% of falls. Factors associated with falls included use of a cane or walker (odds ratio [OR] 2.62; 95% confidence interval [CI] 1.66-4.14), income <$25,000 (OR 1.85; 95% CI 1.13-3.04), balance problems (OR 1.28; 95% CI 1.11-1.49), and leg weakness (OR 1.26; 95% CI 1.09-1.46). Fifty-one percent of those who fell (135/265) reported speaking to an HCP about their falls; recommended strategies included safety strategies (53.2%), use of gait assistive devices (42.1%), exercise/balance training (22.2%), and home modifications (16.6%). Factors associated with falls in persons with MS are similar to those in other populations with neurologic diseases. Despite the high incidence of falls, fewer than 50% of people with MS receive information about prevention of falls from an HCP. Copyright © 2011 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  16. "Homelessness and trauma go hand-in-hand": pathways to homelessness among women veterans.

    PubMed

    Hamilton, Alison B; Poza, Ines; Washington, Donna L

    2011-01-01

    Veterans comprise a disproportionate fraction of the nation's homeless population, with women veterans up to four times more likely to be homeless than non-veteran women. This paper provides a grounded description of women veterans' pathways into homelessness. Three focus groups were held in Los Angeles, California, with a total of 29 homeless women veterans. Five predominant "roots" (precipitating experiences) initiated pathways toward homelessness: 1) childhood adversity, 2) trauma and/or substance abuse during military service, 3) post-military abuse, adversity, and/or relationship termination, 4) post-military mental health, substance abuse, and/or medical problems, and 5) unemployment. Contextual factors, which promoted development of homelessness in the setting of primary roots, included women veterans' "survivor instinct," lack of social support and resources, sense of isolation, pronounced sense of independence, and barriers to care. These contextual factors also reinforced persistence of the roots of post-military adversity and mental health and substance abuse problems, serving to maintain cycles of chronic homelessness. Collectively, these multiple, interacting roots and contextual factors form a "web of vulnerability" that is a target for action. Multiple points along the pathways to homelessness represent critical junctures for VA and community-based organizations to engage in prevention or intervention efforts on behalf of women veterans. Considering the multiple, interconnected challenges that these women veterans described, solutions to homelessness should address multiple risk factors, include trauma-informed care that acknowledges women veterans' traumatic experiences, and incorporate holistic responses that can contribute to healing and recovery. Published by Elsevier Inc.

  17. Power and instrument strength requirements for Mendelian randomization studies using multiple genetic variants.

    PubMed

    Pierce, Brandon L; Ahsan, Habibul; Vanderweele, Tyler J

    2011-06-01

    Mendelian Randomization (MR) studies assess the causality of an exposure-disease association using genetic determinants [i.e. instrumental variables (IVs)] of the exposure. Power and IV strength requirements for MR studies using multiple genetic variants have not been explored. We simulated cohort data sets consisting of a normally distributed disease trait, a normally distributed exposure, which affects this trait and a biallelic genetic variant that affects the exposure. We estimated power to detect an effect of exposure on disease for varying allele frequencies, effect sizes and samples sizes (using two-stage least squares regression on 10,000 data sets-Stage 1 is a regression of exposure on the variant. Stage 2 is a regression of disease on the fitted exposure). Similar analyses were conducted using multiple genetic variants (5, 10, 20) as independent or combined IVs. We assessed IV strength using the first-stage F statistic. Simulations of realistic scenarios indicate that MR studies will require large (n > 1000), often very large (n > 10,000), sample sizes. In many cases, so-called 'weak IV' problems arise when using multiple variants as independent IVs (even with as few as five), resulting in biased effect estimates. Combining genetic factors into fewer IVs results in modest power decreases, but alleviates weak IV problems. Ideal methods for combining genetic factors depend upon knowledge of the genetic architecture underlying the exposure. The feasibility of well-powered, unbiased MR studies will depend upon the amount of variance in the exposure that can be explained by known genetic factors and the 'strength' of the IV set derived from these genetic factors.

  18. Longitudinal patterns and predictors of multiple health risk behaviors among adolescents: The TRAILS study.

    PubMed

    de Winter, Andrea F; Visser, Leenke; Verhulst, Frank C; Vollebergh, Wilma A M; Reijneveld, Sijmen A

    2016-03-01

    Most studies on multiple health risk behaviors among adolescents have cross-sectionally studied a limited number of health behaviors or determinants. To examine the prevalence, longitudinal patterns and predictors of individual and multiple health risk behaviors among adolescents. Eight health risk behaviors (no regular consumption of fruit, vegetables or breakfast, overweight or obesity, physical inactivity, smoking, alcohol use and cannabis use) were assessed in a prospective population study (second and third wave). Participants were assessed in three waves between ages 10 and 17 (2001-2008; n=2230). Multiple linear regression was used to assess the influence of gender, self-control, parental health risk behaviors, parental monitoring and socioeconomic factors on the number of health risk behaviors adjusted for preceding multiple health risk behaviors (analysis: 2013-2014). Rates of >5 health risk behaviors were high: 3.6% at age 13.5 and 10.2% at age 16. Smoking at age 13.5 was frequently associated with health risk behaviors at age 16. No regular consumption of fruit, vegetables and breakfast, overweight or obesity, physical inactivity and smoking predicted the co-occurrence of health risk behaviors at follow-up. Significant predictors of the development of multiple health risk behaviors were adolescents' levels of self-control, socioeconomic status and maternal smoking. Multiple health risk behaviors are common among adolescents. Individual and social factors predict changes in multiple health risk behaviors, showing that prevention targeting multiple risk behaviors is needed. Special attention should be paid to adolescents with low self-control and families with low socioeconomic status or a mother who smokes. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Extrinsic extinction cross-section in the multiple acoustic scattering by fluid particles

    NASA Astrophysics Data System (ADS)

    Mitri, F. G.

    2017-04-01

    Cross-sections (and their related energy efficiency factors) are physical parameters used in the quantitative analysis of different phenomena arising from the interaction of waves with a particle (or multiple particles). Earlier works with the acoustic scattering theory considered such quadratic (i.e., nonlinear) quantities for a single scatterer, although a few extended the formalism for a pair of scatterers but were limited to the scattering cross-section only. Therefore, the standard formalism applied to viscous particles is not suitable for the complete description of the cross-sections and energy balance of the multiple-particle system because both absorption and extinction phenomena arise during the multiple scattering process. Based upon the law of the conservation of energy, this work provides a complete comprehensive analysis for the extrinsic scattering, absorption, and extinction cross-sections (i.e., in the far-field) of a pair of viscous scatterers of arbitrary shape, immersed in a nonviscous isotropic fluid. A law of acoustic extinction taking into consideration interparticle effects in wave propagation is established, which constitutes a generalized form of the optical theorem in multiple scattering. Analytical expressions for the scattering, absorption, and extinction cross-sections are derived for plane progressive waves with arbitrary incidence. The mathematical expressions are formulated in partial-wave series expansions in cylindrical coordinates involving the angle of incidence, the addition theorem for the cylindrical wave functions, and the expansion coefficients of the scatterers. The analysis shows that the multiple scattering cross-section depends upon the expansion coefficients of both scatterers in addition to an interference factor that depends on the interparticle distance. However, the extinction cross-section depends on the expansion coefficients of the scatterer located in a particular system of coordinates, in addition to the interference term. Numerical examples illustrate the analysis for two viscous fluid circular cylindrical cross-sections immersed in a non-viscous fluid. Computations for the (non-dimensional) scattering, absorption, and extinction cross-section factors are performed with particular emphasis on varying the angle of incidence, the interparticle distance, and the sizes, and the physical properties of the particles. A symmetric behavior is observed for the dimensionless multiple scattering cross-section, while asymmetries arise for both the dimensionless absorption and extinction cross-sections with respect to the angle of incidence. The present analysis provides a complete analytical and computational method for the prediction of cross-section and energy efficiency factors in multiple acoustic scattering of plane waves of arbitrary incidence by a pair of scatterers. The results can be used as a priori information in the direct or inverse characterization of multiple scattering systems such as acoustically engineered fluid metamaterials with reconfigurable periodicities, cloaking devices, liquid crystals, and other applications.

  20. A systematic analysis of factors localized to damaged chromatin reveals PARP-dependent recruitment of transcription factors

    PubMed Central

    Izhar, Lior; Adamson, Britt; Ciccia, Alberto; Lewis, Jedd; Pontano-Vaites, Laura; Leng, Yumei; Liang, Anthony C.; Westbrook, Thomas F.; Harper, J. Wade; Elledge, Stephen J.

    2015-01-01

    Localization to sites of DNA damage is a hallmark of DNA damage response (DDR) proteins. To identify new DDR factors, we screened epitope-tagged proteins for localization to sites of chromatin damaged by UV laser microirradiation and found >120 proteins that localize to damaged chromatin. These include the BAF tumor suppressor complex and the ALS candidate protein TAF15. TAF15 contains multiple domains that bind damaged chromatin in a PARP-dependent manner, suggesting a possible role as glue that tethers multiple PAR chains together. Many positives were transcription factors and >70% of randomly tested transcription factors localized to sites of DNA damage and approximately 90% were PARP-dependent for localization. Mutational analyses showed that localization to damaged chromatin is DNA-binding domain-dependent. By examining Hoechst staining patterns at damage sites, we see evidence of chromatin decompaction that is PARP-dependent. We propose that PARP-regulated chromatin remodeling at sites of damage allows transient accessibility of DNA-binding proteins. PMID:26004182

  1. Predictors of health-related quality of life among low-income midlife women.

    PubMed

    Ham, Ok Kyung

    2011-02-01

    The purpose of this study was to determine whether any of the sociodemographic, biomedical, psychosocial, and medical-care factors independently predict health-related quality of life (HRQoL) among low-income women. Cross-sectional data were used to predict factors that determine HRQoL. A survey was conducted targeting a convenience sample of 200 midlife women. Blood samples were drawn from all participants, who also received a physical examination. Hierarchical multiple regression analysis was used to test the independent effects of each factor. The study found that sociodemographic and psychosocial factors were independently associated with HRQoL. Compared to married women, widowed or divorced women had significantly lower HRQoL, whereas those with higher levels of stress perception and those not performing regular exercise had significantly lower HRQoL (p < .01). The full model accounted for 44.7% of the variance in HRQoL. The HRQoL of low-income midlife women was associated with multiple factors, with stress perception exerting the major influence.

  2. Employment characteristics and socioeconomic factors associated with disparities in smoking abstinence and former smoking among U.S. workers.

    PubMed

    Fagan, Pebbles; Shavers, Vickie L; Lawrence, Deirdre; Gibson, James Todd; O'Connell, Mary E

    2007-11-01

    This study examines the associations among employment and socioeconomic factors and the outcomes, current smoking, cigarette abstinence and former smoking among adult U.S. workers ages 18-64 (n=288,813). Multivariate logistic regression was used to examine the associations among the variables using cross-sectional data from the 1998-1999 and 2001-2002 Tobacco Use Supplements to the Current Population Survey. Lower odds of current smoking was observed among part-time workers compared to those working variable hours and multiple job holders compared to persons holding one job. The self-employed, part-time workers and multiple job holders had higher odds of former smoking than comparison groups. Employment factors were not associated with short-term abstinence or 12-month abstinence from smoking, but income, education, marital status, and duration of smoking were associated with 12-month abstinence. These data suggest that while employment factors are associated with current and former smoking, socioeconomic factors are associated with long-term quitting.

  3. Occupational and non-occupational factors associated with work-related injuries among construction workers in the USA

    PubMed Central

    Dong, Xiuwen Sue; Wang, Xuanwen; Largay, Julie A.

    2015-01-01

    Background: Many factors contribute to occupational injuries. However, these factors have been compartmentalized and isolated in most studies. Objective: To examine the relationship between work-related injuries and multiple occupational and non-occupational factors among construction workers in the USA. Methods: Data from the 1988–2000 National Longitudinal Survey of Youth, 1979 cohort (N = 12,686) were analyzed. Job exposures and health behaviors were examined and used as independent variables in four multivariate logistic regression models to identify associations with occupational injuries. Results: After controlling for demographic variables, occupational injuries were 18% (95% CI: 1.04–1.34) more likely in construction than in non-construction. Blue-collar occupations, job physical efforts, multiple jobs, and long working hours accounted for the escalated risk in construction. Smoking, obesity/overweight, and cocaine use significantly increased the risk of work-related injury when demographics and occupational factors were held constant. Conclusions: Workplace injuries are better explained by simultaneously examining occupational and non-occupational characteristics. PMID:25816923

  4. Strategies for Controlled Delivery of Biologics for Cartilage Repair

    PubMed Central

    Lam, Johnny; Lu, Steven; Kasper, F. Kurtis; Mikos, Antonios G.

    2014-01-01

    The delivery of biologics is an important component in the treatment of osteoarthritis and the functional restoration of articular cartilage. Numerous factors have been implicated in the cartilage repair process, but the uncontrolled delivery of these factors may not only reduce their full reparative potential and can also cause unwanted morphological effects. It is therefore imperative to consider the type of biologic to be delivered, the method of delivery, and the temporal as well as spatial presentation of the biologic to achieve the desired effect in cartilage repair. Additionally, the delivery of a single factor may not be sufficient in guiding neo-tissue formation, motivating recent research towards the delivery of multiple factors. This review will discuss the roles of various biologics involved in cartilage repair and the different methods of delivery for appropriate healing responses. A number of spatiotemporal strategies will then be emphasized for the controlled delivery of single and multiple bioactive factors in both in vitro and in vivo cartilage tissue engineering applications. PMID:24993610

  5. GENDER DIFFERENCES IN RISK/PROTECTION PROFILES FOR LOW ACADEMIC PERFORMANCE.

    PubMed

    Whitney, Stephen D; Renner, Lynette M; Herrenkohl, Todd I

    2010-05-01

    Using holistic-interactionistic theory, the simultaneous nature of risk and protection factors for both males and females (age 6-11 in Wave 1) is examined using Latent Profile Analysis (LPA). Risk/protection classes are estimated using multiple risk factor variables (e.g., physical child abuse) and multiple protective factors (e.g., extracurricular activities). These risk/protection classes were used to predict low academic performance. For both males and females, high risk, low protection individuals were significantly more likely to experience low academic performance than low risk, high protection cases. Gender differences emerged in a class for females that included the importance of parental/peer disapproval of anti-social behavior as a protective factor that was not present for males. Findings support elements of the holistic-interactionistic theory for human development and suggest the need to examine risk and protective factors in combination to account for their shared influences on developmental outcomes. Implications for youths underperforming academically are discussed.

  6. User's manual for CNVUFAC, the general dynamics heat-transfer radiation view factor program

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

    Wong, R. L.

    CNVUFAC, the General Dynamics heat-transfer radiation veiw factor program, has been adapted for use on the LLL CDC 7600 computer system. The input and output have been modified, and a node incrementing logic was included to make the code compatible with the TRUMP thermal analyzer and related codes. The program performs the multiple integration necessary to evaluate the geometric black-body radiaton node to node view factors. Card image output that contains node number and view factor information is generated for input into the related program GRAY. Program GRAY is then used to include the effects of gray-body emissivities and multiplemore » reflections, generating the effective gray-body view factors usable in TRUMP. CNVUFAC uses an elemental area summation scheme to evaluate the multiple integrals. The program permits shadowing and self-shadowing. The basic configuration shapes that can be considered are cylinders, cones, spheres, ellipsoids, flat plates, disks, toroids, and polynomials of revolution. Portions of these shapes can also be considered.« less

  7. Characteristic investigation of Golay9 multiple mirror telescope with a spherical primary mirror

    NASA Astrophysics Data System (ADS)

    Wu, Feng; Wu, Quanying; Zhu, Xifang; Xiang, Ruxi; Qian, Lin

    2017-10-01

    The sparse aperture provides a novel solution to the manufacturing difficulties of modern super large telescopes. Golay configurations are optimal in the sparse aperture family. Characteristics of the Golay9 multiple mirror telescope having a spherical primary mirror are investigated. The arrangement of the nine sub-mirrors is discussed after the planar Golay9 configuration is analyzed. The characteristics of the entrance pupil are derived by analyzing the sub-aperture shapes with different relative apertures and sub-mirror sizes. Formulas about the fill factor and the overlay factor are deduced. Their maximal values are presented based on the derived tangency condition. Formulas for the point spread function (PSF) and the modulation transfer function (MTF) of the Golay9 MMT are also deduced. Two Golay9 MMT have been developed by Zemax simulation. Their PSF, MTF, fill factors, and overlay factors prove that our theoretical results are consistent with the practical simulation ones.

  8. Space adaptation syndrome: multiple etiological factors and individual differences

    NASA Technical Reports Server (NTRS)

    Lackner, J. R.; DiZio, P.

    1991-01-01

    Space motion sickness is a significant operational concern in the American and Soviet space programs. Nearly 70% of all astronauts and cosmonauts are affected to some degree during their first several days of flight. It is now beginning to appear that space motion sickness like terrestrial motion sickness is the consequence of multiple etiological factors. As we come to understand basic mechanisms of spatial orientation and sensory-motor adaptation we can begin to predict etiological factors in different motion environments. Individuals vary greatly in the extent to which they are susceptible to these different factors. However, individuals seem to be relatively self-consistent in terms of their rates of adaptation to provocative stimulation and their retention of adaptation. Attempts to relate susceptibility to motion sickness during the microgravity phases of parabolic flight maneuvers to vestibular function under 1G and 0G test conditions are described.

  9. Multiple sclerosis: geoepidemiology, genetics and the environment.

    PubMed

    Milo, Ron; Kahana, Esther

    2010-03-01

    Multiple sclerosis (MS) is a chronic immune-mediated demyelinating disease of the central nervous system characterized by relapses and remissions. The risk of acquiring this complex disease is associated with exposure to environmental factors in genetically susceptible individuals. The epidemiology of MS has been extensively studied. We review the geographic epidemiology of the disease, the influence of immigration, age at immigration, clustering and epidemics. Various presumptive risk factors are discussed such as ultraviolet radiation, vitamin D, Epstein-Barr virus and infectious mononucleosis, other infectious agents and non-infectious factors. Two different hypotheses, the hygiene hypothesis and the prevalence hypothesis, were proposed to explain these environmental risk factors for MS. The epidemiological data, combined with pathological and immunological data, may contribute to the debate whether MS is an autoimmune disease, a latent or persistent viral disease, or a neurodegenerative disease. 2009 Elsevier B.V. All rights reserved.

  10. [Adoption of new technologies by health services: the challenge of analyzing relevant factors].

    PubMed

    Trindade, Evelinda

    2008-05-01

    The exponential increase in the incorporation of health technologies has been considered a key factor in increased expenditures by the health sector. Such decisions involve multiple levels and stakeholders. Decentralization has multiplied the decision-making levels, with numerous difficult choices and limited resources. The interrelationship between stakeholders is complex, in creative systems with multiple determinants and confounders. The current review discusses the interaction between the factors influencing the decisions to incorporate technologies by health services, and proposes a structure for their analysis. The application and intensity of these factors in decision-making and the incorporation of products and programs by health services shapes the installed capacity of local and regional networks and modifies the health system. Empirical observation of decision-making and technology incorporation in Brazilian health services poses an important challenge. The structured recognition and measurement of these variables can assist proactive planning of health services.

  11. Analysis of factors that inhibiting implementation of Information Security Management System (ISMS) based on ISO 27001

    NASA Astrophysics Data System (ADS)

    Tatiara, R.; Fajar, A. N.; Siregar, B.; Gunawan, W.

    2018-03-01

    The purpose of this research is to determine multi factors that inhibiting the implementation of the ISMS based on ISO 2700. It is also to propose a follow-up recommendation on the factors that inhibit the implementation of the ISMS. Data collection is derived from questionnaires to 182 respondents from users in data center operation (DCO) at bca, Indonesian telecommunication international (telin), and data centre division at Indonesian Ministry of Health. We analysing data collection with multiple linear regression analysis and paired t-test. The results are multiple factors which inhibiting the implementation of the ISMS from the three organizations which has implement and operate the ISMS, ISMS documentation management, and continual improvement. From this research, we concluded that the processes of implementation in ISMS is the necessity of the role of all parties in succeeding the implementation of the ISMS continuously.

  12. Synthetic Biology Platform for Sensing and Integrating Endogenous Transcriptional Inputs in Mammalian Cells.

    PubMed

    Angelici, Bartolomeo; Mailand, Erik; Haefliger, Benjamin; Benenson, Yaakov

    2016-08-30

    One of the goals of synthetic biology is to develop programmable artificial gene networks that can transduce multiple endogenous molecular cues to precisely control cell behavior. Realizing this vision requires interfacing natural molecular inputs with synthetic components that generate functional molecular outputs. Interfacing synthetic circuits with endogenous mammalian transcription factors has been particularly difficult. Here, we describe a systematic approach that enables integration and transduction of multiple mammalian transcription factor inputs by a synthetic network. The approach is facilitated by a proportional amplifier sensor based on synergistic positive autoregulation. The circuits efficiently transduce endogenous transcription factor levels into RNAi, transcriptional transactivation, and site-specific recombination. They also enable AND logic between pairs of arbitrary transcription factors. The results establish a framework for developing synthetic gene networks that interface with cellular processes through transcriptional regulators. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  13. Modeling non-linear growth responses to temperature and hydrology in wetland trees

    NASA Astrophysics Data System (ADS)

    Keim, R.; Allen, S. T.

    2016-12-01

    Growth responses of wetland trees to flooding and climate variations are difficult to model because they depend on multiple, apparently interacting factors, but are a critical link in hydrological control of wetland carbon budgets. To more generally understand tree growth to hydrological forcing, we modeled non-linear responses of tree ring growth to flooding and climate at sub-annual time steps, using Vaganov-Shashkin response functions. We calibrated the model to six baldcypress tree-ring chronologies from two hydrologically distinct sites in southern Louisiana, and tested several hypotheses of plasticity in wetlands tree responses to interacting environmental variables. The model outperformed traditional multiple linear regression. More importantly, optimized response parameters were generally similar among sites with varying hydrological conditions, suggesting generality to the functions. Model forms that included interacting responses to multiple forcing factors were more effective than were single response functions, indicating the principle of a single limiting factor is not correct in wetlands and both climatic and hydrological variables must be considered in predicting responses to hydrological or climate change.

  14. Learning to represent spatial transformations with factored higher-order Boltzmann machines.

    PubMed

    Memisevic, Roland; Hinton, Geoffrey E

    2010-06-01

    To allow the hidden units of a restricted Boltzmann machine to model the transformation between two successive images, Memisevic and Hinton (2007) introduced three-way multiplicative interactions that use the intensity of a pixel in the first image as a multiplicative gain on a learned, symmetric weight between a pixel in the second image and a hidden unit. This creates cubically many parameters, which form a three-dimensional interaction tensor. We describe a low-rank approximation to this interaction tensor that uses a sum of factors, each of which is a three-way outer product. This approximation allows efficient learning of transformations between larger image patches. Since each factor can be viewed as an image filter, the model as a whole learns optimal filter pairs for efficiently representing transformations. We demonstrate the learning of optimal filter pairs from various synthetic and real image sequences. We also show how learning about image transformations allows the model to perform a simple visual analogy task, and we show how a completely unsupervised network trained on transformations perceives multiple motions of transparent dot patterns in the same way as humans.

  15. Multiple Family Groups for Child Behavior Difficulties: Retention Among Child Welfare-Involved Caregivers

    ERIC Educational Resources Information Center

    Gopalan, Geetha; Fuss, Ashley; Wisdom, Jennifer P.

    2015-01-01

    Purpose: The Multiple Family Group (MFG) service delivery model to reduce childhood disruptive behavior disorders has shown promise in engaging child welfare-involved families. This qualitative study examines caregivers' perceptions of factors that influence retention in MFGs among child welfare-involved families. Methods: Twenty-five…

  16. Multisite-multivariable sensitivity analysis of distributed watershed models: enhancing the perceptions from computationally frugal methods

    USDA-ARS?s Scientific Manuscript database

    This paper assesses the impact of different likelihood functions in identifying sensitive parameters of the highly parameterized, spatially distributed Soil and Water Assessment Tool (SWAT) watershed model for multiple variables at multiple sites. The global one-factor-at-a-time (OAT) method of Morr...

  17. Self-Rated Estimates of Multiple Intelligences Based on Approaches to Learning

    ERIC Educational Resources Information Center

    Bowles, Terry

    2008-01-01

    To date questionnaires that measure Multiple Intelligences (MIs) have typically not been systematically developed, have poor psychometric properties, and relatively low reliability. The aim of this research was to define the factor structure, and reliability of nine talents which are the behavioural outcomes of MIs, using items representing…

  18. Temporal Assessment of the Impact of Exposure to Cow Feces in Two Watersheds by Multiple Host-Specific PCR Assays

    EPA Science Inventory

    Exposure to feces in two watersheds with different management histories was assessed by tracking cattle feces bacterial populations using multiple host-specific PCR assays. In addition, environmental factors affecting the occurrence of these markers were identified. Each assay wa...

  19. Temporal Assessment of the Impact of Exposure to Cow Feces inTwo Watersheds by Multiple Host-Specific PCR Assays

    EPA Science Inventory

    Fecal exposure in two watersheds with different management histories was assessed by tracking cattle fecal bacterial populations using multiple host-specific PCR assays. In addition, environmental factors affecting the occurrence of these markers were identified. Each assay was t...

  20. Prospective Mathematics Teachers' Sense Making of Polynomial Multiplication and Factorization Modeled with Algebra Tiles

    ERIC Educational Resources Information Center

    Caglayan, Günhan

    2013-01-01

    This study is about prospective secondary mathematics teachers' understanding and sense making of representational quantities generated by algebra tiles, the quantitative units (linear vs. areal) inherent in the nature of these quantities, and the quantitative addition and multiplication operations--referent preserving versus referent…

  1. The Impact of Noninvariant Intercepts in Latent Means Models

    ERIC Educational Resources Information Center

    Whittaker, Tiffany A.

    2013-01-01

    Latent means methods such as multiple-indicator multiple-cause (MIMIC) and structured means modeling (SMM) allow researchers to determine whether or not a significant difference exists between groups' factor means. Strong invariance is typically recommended when interpreting latent mean differences. The extent of the impact of noninvariant…

  2. Modeling month-season of birth as a risk factor in mouse models of chronic disease: from multiple sclerosis to autoimmune encephalomyelitis.

    PubMed

    Reynolds, Jacob D; Case, Laure K; Krementsov, Dimitry N; Raza, Abbas; Bartiss, Rose; Teuscher, Cory

    2017-06-01

    Month-season of birth (M-SOB) is a risk factor in multiple chronic diseases, including multiple sclerosis (MS), where the lowest and greatest risk of developing MS coincide with the lowest and highest birth rates, respectively. To determine whether M-SOB effects in such chronic diseases as MS can be experimentally modeled, we examined the effect of M-SOB on susceptibility of C57BL/6J mice to experimental autoimmune encephalomyelitis (EAE). As in MS, mice that were born during the M-SOB with the lowest birth rate were less susceptible to EAE than mice born during the M-SOB with the highest birth rate. We also show that the M-SOB effect on EAE susceptibility is associated with differential production of multiple cytokines/chemokines by neuroantigen-specific T cells that are known to play a role in EAE pathogenesis. Taken together, these results support the existence of an M-SOB effect that may reflect seasonally dependent developmental differences in adaptive immune responses to self-antigens independent of external stimuli, including exposure to sunlight and vitamin D. Moreover, our documentation of an M-SOB effect on EAE susceptibility in mice allows for modeling and detailed analysis of mechanisms that underlie the M-SOB effect in not only MS but in numerous other diseases in which M-SOB impacts susceptibility.-Reynolds, J. D., Case, L. K., Krementsov, D. N., Raza, A., Bartiss, R., Teuscher, C. Modeling month-season of birth as a risk factor in mouse models of chronic disease: from multiple sclerosis to autoimmune encephalomyelitis. © FASEB.

  3. Physical and social environment and the risk of multiple sclerosis.

    PubMed

    Magyari, Melinda; Koch-Henriksen, Nils; Pfleger, Claudia C; Sørensen, Per Soelberg

    2014-09-01

    The incidence of multiple sclerosis (MS) in Denmark has doubled in women since 1970, whereas it has been almost unchanged in men. The rapid epidemiological changes suggest that environmental factors may modify the risk of MS. To investigate whether occupational, physical, or social environmental influence the risk of MS differently in women than in men. The cohort consists of all 1403 patients (939 women, 464 men) identified through Danish Multiple Sclerosis Registry aged 1-55 of years at clinical onset between 2000 and 2004, and up to 25 control persons for each case, matched by sex, year of birth and residential municipality. The same cohort was previously used to investigate the influence of the reproductive factors on the risk of MS. By linkage to Danish population registers we found a slight albeit statistically significant excess for 6 female MS patients who had been employed in agriculture: OR 3.52; 95% CI 1.38-9.00, p=0.008 (0.046 when corrected for multiple significance) and a trend for exposure to outdoor work in 12 : OR 1.94, 95% CI 1.06-3.55, p=0.03 (0.09 when corrected for multiple significance), but the numbers of cases were small, and the effects were not found in men. Educational level, housing conditions in youth, or the presence of children unrelated by blood in the household did not influence the risk of MS. Our study did not reveal any additional factors beyond the previously published childbirths which could explain the extent of the MS incidence increase in women. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Future Directions in Vulnerability to Depression among Youth: Integrating Risk Factors and Processes across Multiple Levels of Analysis

    PubMed Central

    Hankin, Benjamin L.

    2014-01-01

    Depression is a developmental phenomenon. Considerable progress has been made in describing the syndrome, establishing its prevalence and features, providing clues as to its etiology, and developing evidence-based treatment and prevention options. Despite considerable headway in distinct lines of vulnerability research, there is an explanatory gap in the field ability to more comprehensively explain and predict who is likely to become depressed, when, and why. Still, despite clear success in predicting moderate variance for future depression, especially with empirically rigorous methods and designs, the heterogeneous and multi-determined nature of depression suggests that additional etiologies need to be included to advance knowledge on developmental pathways to depression. This paper advocates for a multiple levels of analysis approach to investigating vulnerability to depression across the lifespan and providing a more comprehensive understanding of its etiology. One example of a multiple levels of analysis model of vulnerabilities to depression is provided that integrates the most accessible, observable factors (e.g., cognitive and temperament risks), intermediate processes and endophenotypes (e.g., information processing biases, biological stress physiology, and neural activation and connectivity), and genetic influences (e.g., candidate genes and epigenetics). Evidence for each of these factors as well as their cross-level integration is provided. Methodological and conceptual considerations important for conducting integrative, multiple levels of depression vulnerability research are discussed. Finally, translational implications for how a multiple levels of analysis perspective may confer additional leverage to reduce the global burden of depression and improve care are considered. PMID:22900513

  5. An Exploration of Factors Influencing Effective Teachers' Decisions to Remain in Urban School Settings

    ERIC Educational Resources Information Center

    Grizzle, Alison L.

    2010-01-01

    Existing problems identified in the literature on teacher retention and resilience include (a) a gap in understanding factors influencing urban teacher retention; (b) lack of clarity on multiple factors swaying teachers' decisions to remain despite challenges; (c) overlapping definitions of teacher retention, attrition, and resilience; and (d)…

  6. Concepts and considerations of tooth wear: Part II--The mechanical component.

    PubMed

    Raigrodski, Ariel J; Dogan, Sami

    2008-05-01

    Identification of etiological factors is essential for successful management of tooth wear. In many cases, the diagnosis may be complicated because of the multiple etiologic factors which may confound the clinical appearance of tooth wear. Comprehensively addressing all of these factors is paramount to the long-term success of patient management.

  7. Factors of Role Conflict among Livestock Extension Professionals in Andhra Pradesh, India

    ERIC Educational Resources Information Center

    Sasidhar, P. V. K.; Rao, B. Sudhakar; Sreeramulu, Piedy

    2008-01-01

    To know the factors of role conflict among livestock extension professionals in Andhra Pradesh, India. Study was conducted following ex-post facto research design. Data were collected from 180 respondents through survey questionnaires. The data were subjected to multiple regression and path analyses to know the factors of role conflict.…

  8. Reassessing the Behavior of Principals as a Multiple-Factor in Teachers' Job Satisfaction.

    ERIC Educational Resources Information Center

    Bogler, Ronit

    This paper reports on a study that examined the effects of three factors on teacher satisfaction: principal leadership style (transformational or transactional), principal decision-making strategy (autocratic versus participative), and teachers' perceptions of their occupation. An overview of each of the three factors is provided. For the study, a…

  9. Some environmental and attitudinal characteristics as predictors of mathematical creativity

    NASA Astrophysics Data System (ADS)

    Kanhai, Abhishek; Singh, Bhoodev

    2017-04-01

    There are many things which can be made more useful and interesting through the application of creativity. Self-concept in mathematics and some school environmental factors such as resource adequacy, teachers' support to the students, teachers' classroom control, creative stimulation by the teachers, etc. were selected in the study. The sample of the study comprised 770 seventh grade students. Pearson correlation, multiple correlation, regression equation and multiple discriminant function analyses of variance were used to analyse the data. The result of the study showed that the relationship between mathematical creativity and each attitudinal and environmental characteristic was found to be positive and significant. Index of forecasting efficiency reveals that mathematical creativity may be best predicted by self-concept in mathematics. Environmental factors, resource adequacy and creative stimulation by the teachers' are found to be the most important factors for predicting mathematical creativity, while social-intellectual involvement among students and educational administration of the schools are to be suppressive factors. The multiple correlation between mathematical creativity and attitudinal and school environmental characteristic suggests that the combined contribution of these variables plays a significant role in the development of mathematical creativity. Mahalanobis analysis indicates that self-concept in mathematics and total school environment were found to be contributing significantly to the development of mathematical creativity.

  10. Evolution of male coloration during a post-Pleistocene radiation of Bahamas mosquitofish (Gambusia hubbsi).

    PubMed

    Martin, Ryan A; Riesch, Rüdiger; Heinen-Kay, Justa L; Langerhans, R Brian

    2014-02-01

    Sexual signal evolution can be complex because multiple factors influence the production, transmission, and reception of sexual signals, as well as receivers' responses to them. To grasp the relative importance of these factors in generating signal diversity, we must simultaneously investigate multiple selective agents and signaling traits within a natural system. We use the model system of the radiation of Bahamas mosquitofish (Gambusia hubbsi) inhabiting blue holes to test the effects of resource availability, male body size and other life-history traits, key aspects of the transmission environment, sex ratio, and predation risk on variation in multiple male color traits. Consistent with previous work examining other traits in this system, several color traits have repeatedly diverged between predation regimes, exhibiting greater elaboration in the absence of predators. However, other factors proved influential as well, with variation in resource levels, body size, relative testes size, and background water color being especially important for several color traits. For one prominent signaling trait, orange dorsal fins, we further confirmed a genetic basis underlying population differences using a laboratory common-garden experiment. We illustrate a promising approach for gaining a detailed understanding of the many contributing factors in the evolution of multivariate sexual signals. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  11. Attack risk for butterflies changes with eyespot number and size

    PubMed Central

    Ho, Sebastian; Schachat, Sandra R.; Piel, William H.; Monteiro, Antónia

    2016-01-01

    Butterfly eyespots are known to function in predator deflection and predator intimidation, but it is still unclear what factors cause eyespots to serve one function over the other. Both functions have been demonstrated in different species that varied in eyespot size, eyespot number and wing size, leaving the contribution of each of these factors to butterfly survival unclear. Here, we study how each of these factors contributes to eyespot function by using paper butterfly models, where each factor is varied in turn, and exposing these models to predation in the field. We find that the presence of multiple, small eyespots results in high predation, whereas single large eyespots (larger than 6 mm in diameter) results in low predation. These data indicate that single large eyespots intimidate predators, whereas multiple small eyespots produce a conspicuous, but non-intimidating signal to predators. We propose that eyespots may gain an intimidation function by increasing in size. Our measurements of eyespot size in 255 nymphalid butterfly species show that large eyespots are relatively rare and occur predominantly on ventral wing surfaces. By mapping eyespot size on the phylogeny of the family Nymphalidae, we show that these large eyespots, with a potential intimidation function, are dispersed throughout multiple nymphalid lineages, indicating that phylogeny is not a strong predictor of eyespot size. PMID:26909190

  12. Persian adaptation of a questionnaire of environmental risk factors in multiple sclerosis (EnvIMS-Q).

    PubMed

    Sahraian, Mohammad Ali; Naghshineh, Hoda; Shati, Mohsen; Jahromi, Soodeh Razeghi; Rezaei, Niloofar

    2016-11-01

    It seems that gene-environment interaction play most important role in Multiple Sclerosis development. Increasing the incidence and prevalence of MS during the recent decades in the low prevalence area such as Iran is explained better by environment factors. Environmental Risk Factors in Multiple Sclerosis (the 'EnvIMS-Q') is a 6-page self-administered questionnaire for case control studies. the objectives of study are validation and adaptation of the EnvIMS-Q' then development of a Persian version for case control studies in Persian population. This questionnaire translated literally and in culturally relevant form, then content validation process was done by three groups' experts. According to giving rating to each item, each section and the whole instrument, we calculated their content validation indexes and also added some new questions and a new section to EnvIMS-Q. Finally, we analyzed repeatability of the answers within a 4 weeks interval. Relevancy and clarity indexes of all items were more than 80%. Scale relevancy index equaled 99% and scale clarity index equaled 97%. Repeatability of most items was acceptable. the use of standardized validated questionnaires will assist the researchers to perform local studies on the role of environmental factors on the basis of reliable data. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Management and Outcomes Among Chinese Hospitalized Patients With Established Cardiovascular Disease or Multiple Risk Factors.

    PubMed

    Yang, Jingang; Yang, Yuejin; Gu, Hongqiu; Li, Wei; Hu, Dayi

    2016-02-01

    We assessed the management and outcomes among hospitalized patients with coronary artery disease (CAD), stroke, peripheral artery disease (PAD), or with multiple (≥ 2) cardiovascular (CV) risk factors (multiple risk factors [MRFs]). We retrospectively studied 3732 hospitalized patients of either CV disease or ≥ 2 risk factors for atherothrombosis from October 2004 to January 2005. Outcomes included CV death, myocardial infarction (MI), stroke, and hospitalization for atherothrombotic events. About one-third had disease involving ≥ 1 vascular bed. Medication was more intense in patients with CAD than in others. The lowest use of statins and antiplatelet treatment was in the PAD-only group. Patients with PAD experienced a higher CV mortality (5.1%) than the patients with CAD (3.73%) or stroke (4.1%), P < .001. Cardiovascular death ranged from 1.2% for patients with MRFs, 2.8% for patients with 1-bed disease, 4.7% for patients with 2-bed disease to 6.4% for patients with 3-bed disease (P for trend <.001). For hospitalized patients with established atherosclerotic arterial disease, a substantial increase in CV event rates occurs with increasing numbers of affected arterial beds. Patients with PAD were at an especially high risk. © The Author(s) 2015.

  14. Multiple sclerosis and employment: Associations of psychological factors and work instability.

    PubMed

    Wicks, Charlotte Rose; Ward, Karl; Stroud, Amanda; Tennant, Alan; Ford, Helen L

    2016-10-12

    People with multiple sclerosis often stop working earlier than expected. Psychological factors may have an impact on job retention. Investigation may inform interventions to help people stay in work. To investigate the associations between psychological factors and work instability in people with multiple sclerosis. A multi-method, 2-phased study. Focus groups were held to identify key themes. Questionnaire packs using validated scales of the key themes were completed at baseline and at 8-month follow-up. Four key psychological themes emerged. Out of 208 study subjects 57.2% reported medium/high risk of job loss, with marginal changes at 8 months. Some psychological variables fluctuated significantly, e.g. depression fell from 24.6% to 14.5%. Work instability and anxiety and depression were strongly correlated (χ2 p < 0.001). Those with probable depression at baseline had 7.1 times increased odds of medium/high work instability, and baseline depression levels also predicted later work instability (Hosmer-Lemeshow test 0.899; Nagelkerke R Square 0.579). Psychological factors fluctuated over the 8-month follow-up period. Some psychological variables, including anxiety and depression, were significantly associated with, and predictive of, work instability. Longitudinal analysis should further identify how these psychological attributes impact on work instability and potential job loss in the longer term.

  15. Sociodemographic characteristics and sexual behavior as risk factors for human papillomavirus infection in Saudi Arabia.

    PubMed

    Alhamlan, F S; Khayat, H H; Ramisetty-Mikler, S; Al-Muammar, T A; Tulbah, A M; Al-Badawi, I A; Kurdi, W I; Tulbah, M I; Alkhenizan, A A; Hussain, A N; Ahmed, M; Al-Ahdal, M N

    2016-05-01

    To determine the prevalence and the sociodemographic characteristics and sexual behavior risk factors for human papillomavirus (HPV) infection in a hospital-based cohort of women in Saudi Arabia. Cervical specimens and questionnaire data were collected from women attending clinics in Riyadh, Saudi Arabia. Cervical specimens were examined for abnormal cytology using a standard Pap test and for the presence of HPV-DNA using PCR and reverse line blot hybridization tests. Approximately 73% of the 400 women tested were Saudi nationals. Nearly 50% were under 40 years old (range 22-80 years, mean±standard deviation 41.20±10.43 years). Approximately 17% of the women were HPV-positive. The most commonly detected HPV types were HPV-18 (34%) and HPV-16 (19%), with multiple infections detected in 10% of positive specimens. Multivariate analyses revealed that smoking and multiple partners were significant risk factors for HPV infection (p<0.01). Because of societal challenges and an unsubstantiated assumption of low HPV prevalence, few studies have examined sociodemographic characteristics or sexual behaviors associated with HPV in Saudi women. However, a high prevalence of HPV infection was found, with smoking and multiple partners as significant risk factors, in this hospital-based cohort of predominantly Saudi women. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Changes in compressed neurons from dogs with acute and severe cauda equina constrictions following intrathecal injection of brain-derived neurotrophic factor-conjugated polymer nanoparticles☆

    PubMed Central

    Tan, Junming; Shi, Jiangang; Shi, Guodong; Liu, Yanling; Liu, Xiaohong; Wang, Chaoyang; Chen, Dechun; Xing, Shunming; Shen, Lianbing; Jia, Lianshun; Ye, Xiaojian; He, Hailong; Li, Jiashun

    2013-01-01

    This study established a dog model of acute multiple cauda equina constriction by experimental constriction injury (48 hours) of the lumbosacral central processes in dorsal root ganglia neurons. The repair effect of intrathecal injection of brain-derived neurotrophic factor with 15 mg encapsulated biodegradable poly(lactide-co-glycolide) nanoparticles on this injury was then analyzed. Dorsal root ganglion cells (L7) of all experimental dogs were analyzed using hematoxylin-eosin staining and immunohistochemistry at 1, 2 and 4 weeks following model induction. Intrathecal injection of brain-derived neurotrophic factor can relieve degeneration and inflammation, and elevate the expression of brain-derived neurotrophic factor in sensory neurons of compressed dorsal root ganglion. Simultaneously, intrathecal injection of brain-derived neurotrophic factor obviously improved neurological function in the dog model of acute multiple cauda equina constriction. Results verified that sustained intraspinal delivery of brain-derived neurotrophic factor encapsulated in biodegradable nanoparticles promoted the repair of histomorphology and function of neurons within the dorsal root ganglia in dogs with acute and severe cauda equina syndrome. PMID:25206593

  17. Exploring the pattern of blood donor beliefs in first-time, novice, and experienced donors: differentiating reluctant altruism, pure altruism, impure altruism, and warm glow.

    PubMed

    Ferguson, Eamonn; Atsma, Femke; de Kort, Wim; Veldhuizen, Ingrid

    2012-02-01

    Using constructs from the Theory of Planned Behavior and theories of altruism, this article explores how multiple motivations and beliefs for blood donation are clustered and change across the donor career. In so doing important distinctions, for blood donation, between impure altruism, pure altruism, and warm glow are explored. Measures of intentions, cognitive and affective attitudes, role merger, pure altruism, trust, self-efficacy, subjective and moral norms, and habit formation were assessed in a sample of 12,580 whole blood donors. Analyses showed that a distinction between first-time, novice (one to four donations), and experienced donors (five or more donations) is justified. Principal components analysis and confirmatory factor analytic Multiple-Indicator Multiple-Causal models were used to compare models across these groups. A cognition-behavior (CB) factor, including intentions, was common to all groups. First-time and novice donors were marked by a newly identified motivational factor: "reluctant altruism" (i.e., the motivation to donate because of a lack of trust in others). First-time donors exhibited an impure altruism factor whereas for experienced donors warm glow and pure altruism factors were observed. For first-time donors impure altruism and reluctant altruism were both associated with the CB factor in females and impure altruism only in males. For both sexes reluctant altruism was associated of the CB factor in novice donors and warm glow and pure altruism for experienced donors. New avenues for intervention are suggested by the emergence of reluctant altruism for novice donors and warm glow for experienced donors. The importance of distinguishing aspects of altruism is highlighted. © 2012 American Association of Blood Banks.

  18. A slow-releasing form of prostacyclin agonist (ONO1301SR) enhances endogenous secretion of multiple cardiotherapeutic cytokines and improves cardiac function in a rapid-pacing-induced model of canine heart failure.

    PubMed

    Shirasaka, Tomonori; Miyagawa, Shigeru; Fukushima, Satsuki; Saito, Atsuhiro; Shiozaki, Motoko; Kawaguchi, Naomasa; Matsuura, Nariaki; Nakatani, Satoshi; Sakai, Yoshiki; Daimon, Takashi; Okita, Yutaka; Sawa, Yoshiki

    2013-08-01

    Cardiac functional deterioration in dilated cardiomyopathy (DCM) is known to be reversed by intramyocardial up-regulation of multiple cardioprotective factors, whereas a prostacyclin analog, ONO1301, has been shown to paracrinally activate interstitial cells to release a variety of protective factors. We here hypothesized that intramyocardial delivery of a slow-releasing form of ONO1301 (ONO1301SR) might activate regional myocardium to up-regulate cardiotherapeutic factors, leading to regional and global functional recovery in DCM. ONO1301 elevated messenger RNA and protein level of hepatocyte growth factor, vascular endothelial growth factor, and stromal-derived factor-1 of normal human dermal fibroblasts in a dose-dependent manner in vitro. Intramyocardial delivery of ONO1301SR, which is ONO1301 mixed with polylactic and glycolic acid polymer (PLGA), but not that of PLGA only, yielded significant global functional recovery in a canine rapid pacing-induced DCM model, assessed by echocardiography and cardiac catheterization (n = 5 each). Importantly, speckle-tracking echocardiography unveiled significant regional functional recovery in the ONO1301-delivered territory, consistent to significantly increased vascular density, reduced interstitial collagen accumulation, attenuated myocyte hypertrophy, and reversed mitochondrial structure in the corresponding area. Intramyocardial delivery of ONO1301SR, which is a PLGA-coated slow-releasing form of ONO1301, up-regulated multiple cardiotherapeutic factors in the injected territory, leading to region-specific reverse left ventricular remodeling and consequently a global functional recovery in a rapid-pacing-induced canine DCM model, warranting a further preclinical study to optimize this novel drug-delivery system to treat DCM. Copyright © 2013 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  19. Measurement invariance of big-five factors over the life span: ESEM tests of gender, age, plasticity, maturity, and la dolce vita effects.

    PubMed

    Marsh, Herbert W; Nagengast, Benjamin; Morin, Alexandre J S

    2013-06-01

    This substantive-methodological synergy applies evolving approaches to factor analysis to substantively important developmental issues of how five-factor-approach (FFA) personality measures vary with gender, age, and their interaction. Confirmatory factor analyses (CFAs) conducted at the item level often do not support a priori FFA structures, due in part to the overly restrictive assumptions of CFA models. Here we demonstrate that exploratory structural equation modeling (ESEM), an integration of CFA and exploratory factor analysis, overcomes these problems with the 15-item Big Five Inventory administered as part of the nationally representative British Household Panel Study (N = 14,021; age: 15-99 years, Mage = 47.1). ESEM fitted the data substantially better and resulted in much more differentiated (less correlated) factors than did CFA. Methodologically, we extended ESEM (introducing ESEM-within-CFA models and a hybrid of multiple groups and multiple indicators multiple causes models), evaluating full measurement invariance and latent mean differences over age, gender, and their interaction. Substantively the results showed that women had higher latent scores for all Big Five factors except for Openness and that these gender differences were consistent over the entire life span. Substantial nonlinear age effects led to the rejection of the plaster hypothesis and the maturity principle but did support a newly proposed la dolce vita effect in old age. In later years, individuals become happier (more agreeable and less neurotic), more self-content and self-centered (less extroverted and open), more laid back and satisfied with what they have (less conscientious, open, outgoing and extroverted), and less preoccupied with productivity. PsycINFO Database Record (c) 2013 APA, all rights reserved

  20. Hypoxia and Mucosal Inflammation

    PubMed Central

    Colgan, Sean P.; Campbell, Eric L.; Kominsky, Douglas J.

    2016-01-01

    Sites of inflammation are defined by significant changes in metabolic activity. Recent studies have suggested that O2 metabolism and hypoxia play a prominent role in inflammation so-called “inflammatory hypoxia,” which results from a combination of recruited inflammatory cells (e.g., neutrophils and monocytes), the local proliferation of multiple cell types, and the activation of multiple O2-consuming enzymes during inflammation. These shifts in energy supply and demand result in localized regions of hypoxia and have revealed the important function off the transcription factor HIF (hypoxia-inducible factor) in the regulation of key target genes that promote inflammatory resolution. Analysis of these pathways has provided multiple opportunities for understanding basic mechanisms of inflammation and has defined new targets for intervention. Here, we review recent work addressing tissue hypoxia and metabolic control of inflammation and immunity. PMID:27193451

  1. Effects of controlled whole-body vibration training in improving fall risk factors among individuals with multiple sclerosis: A pilot study.

    PubMed

    Yang, Feng; Finlayson, Marcia; Bethoux, Francois; Su, Xiaogang; Dillon, Loretta; Maldonado, Hector M

    2018-03-01

    The purpose of this study was to systematically examine the effect of an 8-week controlled whole-body vibration training on improving fall risk factors and the bone mineral density among people with multiple sclerosis (PwMS). This study adopted a single group pre-test-post-test design. Twenty-five PwMS (50.3 years SD 14.1) received vibration training on a side-alternating vibration platform. Each training session was repeated three times every week for 8 weeks. Prior to and following the 8-week training course, a battery of fall risk factors were evaluated: the body balance, functional mobility, muscle strength, range of motion, and fear of falling. Bone density at both calcanei was also assessed. Twenty-two participants completed the study. Compared with pre-test, almost all fall risk factors and the bone density measurement were significantly improved at post-test, with moderate to large effect sizes varying between 0.571 and 1.007. The 8-week vibration training was well accepted by PwMS and improved their fall risk factors. The important findings of this study were that vibration training may increase the range of motion of ankle joints on the sagittal plane, lower the fear of falling, and improve bone density. IMPLICATIONS FOR REHABILITATION An 8-week vibration training course could be well-accepted by people with multiple sclerosis (MS). Vibration training improves the risk factors of falls in people living with MS. Vibration training could be a promising rehabilitation intervention in individuals with MS.

  2. Factors predicting work outcome in Japanese patients with schizophrenia: role of multiple functioning levels.

    PubMed

    Sumiyoshi, Chika; Harvey, Philip D; Takaki, Manabu; Okahisa, Yuko; Sato, Taku; Sora, Ichiro; Nuechterlein, Keith H; Subotnik, Kenneth L; Sumiyoshi, Tomiki

    2015-09-01

    Functional outcomes in individuals with schizophrenia suggest recovery of cognitive, everyday, and social functioning. Specifically improvement of work status is considered to be most important for their independent living and self-efficacy. The main purposes of the present study were 1) to identify which outcome factors predict occupational functioning, quantified as work hours, and 2) to provide cut-offs on the scales for those factors to attain better work status. Forty-five Japanese patients with schizophrenia and 111 healthy controls entered the study. Cognition, capacity for everyday activities, and social functioning were assessed by the Japanese versions of the MATRICS Cognitive Consensus Battery (MCCB), the UCSD Performance-based Skills Assessment-Brief (UPSA-B), and the Social Functioning Scale Individuals' version modified for the MATRICS-PASS (Modified SFS for PASS), respectively. Potential factors for work outcome were estimated by multiple linear regression analyses (predicting work hours directly) and a multiple logistic regression analyses (predicting dichotomized work status based on work hours). ROC curve analyses were performed to determine cut-off points for differentiating between the better- and poor work status. The results showed that a cognitive component, comprising visual/verbal learning and emotional management, and a social functioning component, comprising independent living and vocational functioning, were potential factors for predicting work hours/status. Cut-off points obtained in ROC analyses indicated that 60-70% achievements on the measures of those factors were expected to maintain the better work status. Our findings suggest that improvement on specific aspects of cognitive and social functioning are important for work outcome in patients with schizophrenia.

  3. Do climate variables and human density affect Achatina fulica (Bowditch) (Gastropoda: Pulmonata) shell length, total weight and condition factor?

    PubMed

    Albuquerque, F S; Peso-Aguiar, M C; Assunção-Albuquerque, M J T; Gálvez, L

    2009-08-01

    The length-weight relationship and condition factor have been broadly investigated in snails to obtain the index of physical condition of populations and evaluate habitat quality. Herein, our goal was to describe the best predictors that explain Achatina fulica biometrical parameters and well being in a recently introduced population. From November 2001 to November 2002, monthly snail samples were collected in Lauro de Freitas City, Bahia, Brazil. Shell length and total weight were measured in the laboratory and the potential curve and condition factor were calculated. Five environmental variables were considered: temperature range, mean temperature, humidity, precipitation and human density. Multiple regressions were used to generate models including multiple predictors, via model selection approach, and then ranked with AIC criteria. Partial regressions were used to obtain the separated coefficients of determination of climate and human density models. A total of 1.460 individuals were collected, presenting a shell length range between 4.8 to 102.5 mm (mean: 42.18 mm). The relationship between total length and total weight revealed that Achatina fulica presented a negative allometric growth. Simple regression indicated that humidity has a significant influence on A. fulica total length and weight. Temperature range was the main variable that influenced the condition factor. Multiple regressions showed that climatic and human variables explain a small proportion of the variance in shell length and total weight, but may explain up to 55.7% of the condition factor variance. Consequently, we believe that the well being and biometric parameters of A. fulica can be influenced by climatic and human density factors.

  4. Lifestyle and Genetic Predictors of Stiffness Index in Community-dwelling Elderly Korean Men and Women.

    PubMed

    Park, Kyung-Ae; Park, Yeon-Hwan; Suh, Min-Hee; Choi-Kwon, Smi

    2015-09-01

    Differing lifestyle, nutritional, and genetic factors may lead to a differing stiffness index (SI) determined by quantitative ultrasound in elderly men and women. The purpose of this study was to determine SI and the gender-specific factors associated with low SI in a Korean elderly cohort. This was a cross-sectional descriptive study identifying the gender-specific factors related to SI in 252 men and women aged 65 years and greater from local senior centers in Seoul, Korea between January and February 2009. The mean SI of elderly men was significantly higher than that of the women's. A multiple regression analysis reveals that age, nutritional status, and physical activity were predictive factors of lower SI in men, whereas age, alcohol consumption, educational level, and genetic polymorphism were predictive factors for elderly women. Low SI was common in both elderly men and women. We found gender differences in factors linked to low SI. In multiple regression analysis, nutritional status and physical activity were more important factors in men, whereas alcohol consumption, educational level, and genetic polymorphism were significant factors predicting low SI in women. Gender-specific modifiable risk factors associated with low SI should be considered when developing osteoporosis prevention programs for the elderly. Copyright © 2015. Published by Elsevier B.V.

  5. Quantifying the influence of natural and socioeconomic factors and their interactive impact on PM2.5 pollution in China.

    PubMed

    Yang, Dongyang; Wang, Xiaomin; Xu, Jianhua; Xu, Chengdong; Lu, Debin; Ye, Chao; Wang, Zujing; Bai, Ling

    2018-06-04

    PM 2.5 pollution is an environmental issue caused by multiple natural and socioeconomic factors, presenting with significant spatial disparities across mainland China. However, the determinant power of natural and socioeconomic factors and their interactive impact on PM 2.5 pollution is still unclear. In the study, the GeogDetector method was used to quantify nonlinear associations between PM 2.5 and potential factors. This study found that natural factors, including ecological environments and climate, were more influential than socioeconomic factors, and climate was the predominant factor (q = 0.56) in influencing PM 2.5 pollution. Among all interactions of the six influencing factors, the interaction of industry and climate had the largest influence (q = 0.66). Two recognized major contaminated areas were the Tarim Basin in the northwest region and the eastern plain region; the former was mainly influenced by the warm temperate arid climate and desert, and the latter was mainly influenced by the warm temperate semi-humid climate and multiple socioeconomic factors. The findings provided an interpretation of the influencing mechanisms of PM 2.5 pollution, which can contribute to more specific policies aimed at successful PM 2.5 pollution control and abatement. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. The Development of an Instrument to Measure Fourteen Theoretical Factors for the Attribution of Charisma

    DTIC Science & Technology

    1993-09-01

    34great man" (Bass & Stogdill,1990:37-38). Francis Galton in his book Hereditary Genius, maintains that the genius to which he refers is an expression of...to Test 14 Theorized Factors 85 Bibliography .............. ...................... .. 93 Vitae ......................... .................. 96 V List...FACTOR = NURTURING ........... ................ 68 26. PAIRED-T TEST RESULTS FOR EACH FACTOR ......... .. 69 27. BONFERRONI MULTIPLE COMPARISON BASED

  7. Low bone density risk is higher in exercising women with multiple triad risk factors.

    PubMed

    Gibbs, Jenna C; Nattiv, Aurelia; Barrack, Michelle T; Williams, Nancy I; Rauh, Mitchell J; Nichols, Jeanne F; De Souza, Mary Jane

    2014-01-01

    The cumulative effect of the female athlete triad (Triad) risk factors on the likelihood of low bone mineral density (BMD) in exercising women is unclear. This study aimed to determine the risk of low BMD in exercising women with multiple Triad risk factors. We retrospectively examined cross-sectional data from 437 exercising women (mean ± SD age of 18.0 ± 3.5 yr, weighed 57.5 ± 7.1 kg with 24.5% ± 6.1% body fat) obtained at baseline from 4 prospective cohort studies examining Triad risk factors. Questionnaires were completed to obtain information on demographic characteristics, self-reported eating attitudes/behaviors, menstrual function, sport/activity participation, and medication use. Height and body weight were measured. BMD was measured using dual energy x-ray absorptiometry. Low BMD was defined as z-scores of <-1 and ≤-2. Chi-square tests were performed to determine the percentage of women with low BMD who met the criteria for individual (current oligo/amenorrhea, late menarche, low body mass index (BMI), elevated dietary restraint, lean sport/activity participation) or multiple (2, 3, 4, or 5) Triad risk factors. Late menarche and low BMI were associated with the highest percentage of low BMD (z-score < -1), 55% and 54%, respectively, and low BMD (z-score ≤-2), 14% and 16%, respectively. The percentage of participants with low BMD (z-score < -1 and ≤-2) increased from 10% to 62% and from 2% to 18%, respectively, as women met the criteria for an increasing number of Triad risk factors. A cumulative number of Triad risk factors were associated with an increased risk of low BMD, suggesting a dose-response association between the number of Triad risk factors and BMD in exercising women. Further research should be conducted to develop a user-friendly algorithm integrating these indicators of risk for low BMD in exercising women (particularly factors associated with low BMI/body weight, menstrual dysfunction, lean sport/activity participation, and elevated dietary restraint).

  8. Brain-derived neurotrophic factor levels under chronic natalizumab treatment in multiple sclerosis. A preliminary report.

    PubMed

    Văcăraş, Vitalie; Major, Zoltán Zsigmond; Buzoianu, Anca Dana

    Our main purpose was to investigate if the chronic treatment with the disease-modifying drug natalizumab shows quantifiable effect on BDNF levels in multiple sclerosis patients. BDNF plasma concentration was evaluated using enzyme-linked immunosorbent assay in healthy individuals, not treated multiple sclerosis patients and patients treated with natalizumab. Multiple sclerosis patients have a significantly lower amount of peripheral BDNF than healthy individuals. Patients treated with natalizumab have significantly higher BDNF levels than not treated patients. Chronic natalizumab treatment is associated with significantly increased plasma BDNF concentration in multiple sclerosis. Copyright © 2017 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  9. Multiple binding sites for transcriptional repressors can produce regular bursting and enhance noise suppression

    NASA Astrophysics Data System (ADS)

    Lengyel, Iván M.; Morelli, Luis G.

    2017-04-01

    Cells may control fluctuations in protein levels by means of negative autoregulation, where transcription factors bind DNA sites to repress their own production. Theoretical studies have assumed a single binding site for the repressor, while in most species it is found that multiple binding sites are arranged in clusters. We study a stochastic description of negative autoregulation with multiple binding sites for the repressor. We find that increasing the number of binding sites induces regular bursting of gene products. By tuning the threshold for repression, we show that multiple binding sites can also suppress fluctuations. Our results highlight possible roles for the presence of multiple binding sites of negative autoregulators.

  10. 40 CFR 94.218 - Deterioration factor determination.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... family. (b) Calculation procedures—(1) For engines not utilizing aftertreatment technology (e.g... technology (e.g., catalyst). For each applicable emission constituent, a multiplicative deterioration factor.... (iii) Engineering analysis for established technologies. In the case where an engine family uses...

  11. Quantum Double of Yangian of strange Lie superalgebra Qn and multiplicative formula for universal R-matrix

    NASA Astrophysics Data System (ADS)

    Stukopin, Vladimir

    2018-02-01

    Main result is the multiplicative formula for universal R-matrix for Quantum Double of Yangian of strange Lie superalgebra Qn type. We introduce the Quantum Double of the Yangian of the strange Lie superalgebra Qn and define its PBW basis. We compute the Hopf pairing for the generators of the Yangian Double. From the Hopf pairing formulas we derive a factorized multiplicative formula for the universal R-matrix of the Yangian Double of the Lie superalgebra Qn . After them we obtain coefficients in this multiplicative formula for universal R-matrix.

  12. The Blessing and the Curse of the Multiplicative Updates

    NASA Astrophysics Data System (ADS)

    Warmuth, Manfred K.

    Multiplicative updates multiply the parameters by nonnegative factors. These updates are motivated by a Maximum Entropy Principle and they are prevalent in evolutionary processes where the parameters are for example concentrations of species and the factors are survival rates. The simplest such update is Bayes rule and we give an in vitro selection algorithm for RNA strands that implements this rule in the test tube where each RNA strand represents a different model. In one liter of the RNA "soup" there are approximately 1020 different strands and therefore this is a rather high-dimensional implementation of Bayes rule.

  13. Reconstructing Eolian Delivery to the Ulleung Basin (IODP Site U1430) Over the Past 12 Myr

    NASA Astrophysics Data System (ADS)

    Anderson, C. H.; Dunlea, A. G.; Murray, R. W.; Tada, R.; Alvarez Zarikian, C. A.

    2017-12-01

    Spring storms associated with the seasonal phases of the East Asian Monsoon (EAM), transport dust seaward and influence marine sedimentation in adjacent ocean regions. Here, we aim to track changes in the intensity of the EAM since the late Miocene by examining the relative proportions and sources of eolian inputs in marine sediment records. We use bulk sediment recovered from Site U1430 in the Ulleung Basin during Integrated Ocean Drilling Program Expedition 346 in 2013 to examine changes in the EAM over the past 12 Myr. Sediment recovered at this site is clayey silt, nannofossil and diatom oozes, claystone, and basal glauonitic sandstone. We analyze major, trace, and rare earth element concentrations for 72 bulk sediment samples analyzed by ICP-ES and ICP-MS, and interpret this dataset using a variety of multivariate statistical partitioning techniques (Q-mode Factor Analyses (QFA), Multiple Linear Regressions) to investigate sediment provenance. Sedimentologic observations and elemental concentrations indicate the presence of biogenic siliceous and carbonaceous components mixed with aluminosilicates. For example, Si/Al (g/g) reaches local maxima at 3 Ma and 10 Ma in several diatom rich sections, and Ca/Al (g/g) exhibits a peak at 0.58 Ma. Other downhole element ratios exhibit subtle variations, including Ti/Al of 0.05 +/- 0.004 g/g, Sc/Al 2 +/- 0.2 ug/g, and Rb/Al 17 +/- 1.5 ug/g. When plotted in ternary diagrams, samples exhibit offset arrays (La-Th-Sc) or multiple clusters (Zr-Nb-Sc) from an Upper Continental Crust and Mid-Ocean Ridge Basalt mixing line. In Th-Cr-Nb, the data exhibit a V-shaped array. The range of geochemical variability suggests that multiple sources of terrigenous matter and/or volcanic ash are being delivered to the site. The multivariate statistics also indicate the mixing of multiple aluminosilicate sources. Focusing on a suite of seven elements (Al, Ti, Sc, Cr, Rb, Th, La), preliminary QFA suggest that five factors are required to explain 99% of the variability in the dataset. Factors group different co-varying elements: Factor 1 Zr and Th, Factor 2 only Cr, Factor 3 Sc and La, Factor 4 Al and Sc, and Factor 5 with Rb and Th. Terrigenous inputs are likely from several sources including loess and other continental crustal material, and will be discussed further.

  14. [Multiple meningiomas].

    PubMed

    Terrier, L-M; François, P

    2016-06-01

    Multiple meningiomas (MMs) or meningiomatosis are defined by the presence of at least 2 lesions that appear simultaneously or not, at different intracranial locations, without the association of neurofibromatosis. They present 1-9 % of meningiomas with a female predominance. The occurrence of multiple meningiomas is not clear. There are 2 main hypotheses for their development, one that supports the independent evolution of these tumors and the other, completely opposite, that suggests the propagation of tumor cells of a unique clone transformation, through cerebrospinal fluid. NF2 gene mutation is an important intrinsic risk factor in the etiology of multiple meningiomas and some exogenous risk factors have been suspected but only ionizing radiation exposure has been proven. These tumors can grow anywhere in the skull but they are more frequently observed in supratentorial locations. Their histologic types are similar to unique meningiomas of psammomatous, fibroblastic, meningothelial or transitional type and in most cases are benign tumors. The prognosis of these tumors is eventually good and does not differ from the unique tumors except for the cases of radiation-induced multiple meningiomas, in the context of NF2 or when diagnosed in children where the outcome is less favorable. Each meningioma lesion should be dealt with individually and their multiple character should not justify their resection at all costs. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  15. DNA wrapping and distortion by an oligomeric homeodomain protein.

    PubMed

    Williams, Hannah; Jayaraman, Padma-Sheela; Gaston, Kevin

    2008-10-31

    Many transcription factors alter DNA or chromatin structure. Changes in chromatin structure are often brought about by the recruitment of chromatin-binding proteins, chromatin-modifying proteins, or other transcription co-activator or co-repressor proteins. However, some transcription factors form oligomeric assemblies that may themselves induce changes in DNA conformation and chromatin structure. The proline-rich homeodomain (PRH/Hex) protein is a transcription factor that regulates cell differentiation and cell proliferation, and has multiple roles in embryonic development. Earlier, we showed that PRH can repress transcription by multiple mechanisms, including the recruitment of co-repressor proteins belonging to the TLE family of chromatin-binding proteins. Our in vivo crosslinking studies have shown that PRH forms oligomeric complexes in cells and a variety of biophysical techniques suggest that the protein forms octamers. However, as yet we have little knowledge of the role played by PRH oligomerisation in the regulation of promoter activity or of the architecture of promoters that are regulated directly by PRH in cells. Here, we compare the binding of PRH and the isolated PRH homeodomain to DNA fragments with single and multiple PRH sites, using gel retardation assays and DNase I and chemical footprinting. We show that the PRH oligomer binds to multiple sites within the human Goosecoid promoter with high affinity and that the binding of PRH brings about DNA distortion. We suggest that PRH octamers wrap DNA in order to bring about transcriptional repression.

  16. Short-term, high-dose glucocorticoid treatment does not contribute to reduced bone mineral density in patients with multiple sclerosis.

    PubMed

    Olsson, A; Oturai, D B; Sørensen, P S; Oturai, P S; Oturai, A B

    2015-10-01

    Patients with multiple sclerosis (MS) are at increased risk of reduced bone mineral density (BMD). A contributing factor might be treatment with high-dose glucocorticoids (GCs). The objective of this paper is to assess bone mass in patients with MS and evaluate the importance of short-term, high-dose GC treatment and other risk factors that affect BMD in patients with MS. A total of 260 patients with MS received short-term high-dose GC treatment and had their BMD measured by dual x-ray absorptiometry. BMD was compared to a healthy age-matched reference population (Z-scores). Data regarding GCs, age, body mass index (BMI), serum 25(OH)D, disease duration and severity were collected retrospectively and analysed in a multiple linear regression analysis to evaluate the association between each risk factor and BMD. Osteopenia was present in 38% and osteoporosis in 7% of the study population. Mean Z-score was significantly below zero, indicating a decreased BMD in our MS patients. Multiple linear regression analysis showed no significant association between GCs and BMD. In contrast, age, BMI and disease severity were independently associated with both lumbar and femoral BMD. Reduced BMD was prevalent in patients with MS. GC treatment appears not to be the primary underlying cause of secondary osteoporosis in MS patients. © The Author(s), 2015.

  17. Assessing Risk Prediction Models Using Individual Participant Data From Multiple Studies

    PubMed Central

    Pennells, Lisa; Kaptoge, Stephen; White, Ian R.; Thompson, Simon G.; Wood, Angela M.; Tipping, Robert W.; Folsom, Aaron R.; Couper, David J.; Ballantyne, Christie M.; Coresh, Josef; Goya Wannamethee, S.; Morris, Richard W.; Kiechl, Stefan; Willeit, Johann; Willeit, Peter; Schett, Georg; Ebrahim, Shah; Lawlor, Debbie A.; Yarnell, John W.; Gallacher, John; Cushman, Mary; Psaty, Bruce M.; Tracy, Russ; Tybjærg-Hansen, Anne; Price, Jackie F.; Lee, Amanda J.; McLachlan, Stela; Khaw, Kay-Tee; Wareham, Nicholas J.; Brenner, Hermann; Schöttker, Ben; Müller, Heiko; Jansson, Jan-Håkan; Wennberg, Patrik; Salomaa, Veikko; Harald, Kennet; Jousilahti, Pekka; Vartiainen, Erkki; Woodward, Mark; D'Agostino, Ralph B.; Bladbjerg, Else-Marie; Jørgensen, Torben; Kiyohara, Yutaka; Arima, Hisatomi; Doi, Yasufumi; Ninomiya, Toshiharu; Dekker, Jacqueline M.; Nijpels, Giel; Stehouwer, Coen D. A.; Kauhanen, Jussi; Salonen, Jukka T.; Meade, Tom W.; Cooper, Jackie A.; Cushman, Mary; Folsom, Aaron R.; Psaty, Bruce M.; Shea, Steven; Döring, Angela; Kuller, Lewis H.; Grandits, Greg; Gillum, Richard F.; Mussolino, Michael; Rimm, Eric B.; Hankinson, Sue E.; Manson, JoAnn E.; Pai, Jennifer K.; Kirkland, Susan; Shaffer, Jonathan A.; Shimbo, Daichi; Bakker, Stephan J. L.; Gansevoort, Ron T.; Hillege, Hans L.; Amouyel, Philippe; Arveiler, Dominique; Evans, Alun; Ferrières, Jean; Sattar, Naveed; Westendorp, Rudi G.; Buckley, Brendan M.; Cantin, Bernard; Lamarche, Benoît; Barrett-Connor, Elizabeth; Wingard, Deborah L.; Bettencourt, Richele; Gudnason, Vilmundur; Aspelund, Thor; Sigurdsson, Gunnar; Thorsson, Bolli; Kavousi, Maryam; Witteman, Jacqueline C.; Hofman, Albert; Franco, Oscar H.; Howard, Barbara V.; Zhang, Ying; Best, Lyle; Umans, Jason G.; Onat, Altan; Sundström, Johan; Michael Gaziano, J.; Stampfer, Meir; Ridker, Paul M.; Michael Gaziano, J.; Ridker, Paul M.; Marmot, Michael; Clarke, Robert; Collins, Rory; Fletcher, Astrid; Brunner, Eric; Shipley, Martin; Kivimäki, Mika; Ridker, Paul M.; Buring, Julie; Cook, Nancy; Ford, Ian; Shepherd, James; Cobbe, Stuart M.; Robertson, Michele; Walker, Matthew; Watson, Sarah; Alexander, Myriam; Butterworth, Adam S.; Angelantonio, Emanuele Di; Gao, Pei; Haycock, Philip; Kaptoge, Stephen; Pennells, Lisa; Thompson, Simon G.; Walker, Matthew; Watson, Sarah; White, Ian R.; Wood, Angela M.; Wormser, David; Danesh, John

    2014-01-01

    Individual participant time-to-event data from multiple prospective epidemiologic studies enable detailed investigation into the predictive ability of risk models. Here we address the challenges in appropriately combining such information across studies. Methods are exemplified by analyses of log C-reactive protein and conventional risk factors for coronary heart disease in the Emerging Risk Factors Collaboration, a collation of individual data from multiple prospective studies with an average follow-up duration of 9.8 years (dates varied). We derive risk prediction models using Cox proportional hazards regression analysis stratified by study and obtain estimates of risk discrimination, Harrell's concordance index, and Royston's discrimination measure within each study; we then combine the estimates across studies using a weighted meta-analysis. Various weighting approaches are compared and lead us to recommend using the number of events in each study. We also discuss the calculation of measures of reclassification for multiple studies. We further show that comparison of differences in predictive ability across subgroups should be based only on within-study information and that combining measures of risk discrimination from case-control studies and prospective studies is problematic. The concordance index and discrimination measure gave qualitatively similar results throughout. While the concordance index was very heterogeneous between studies, principally because of differing age ranges, the increments in the concordance index from adding log C-reactive protein to conventional risk factors were more homogeneous. PMID:24366051

  18. Assessing risk prediction models using individual participant data from multiple studies.

    PubMed

    Pennells, Lisa; Kaptoge, Stephen; White, Ian R; Thompson, Simon G; Wood, Angela M

    2014-03-01

    Individual participant time-to-event data from multiple prospective epidemiologic studies enable detailed investigation into the predictive ability of risk models. Here we address the challenges in appropriately combining such information across studies. Methods are exemplified by analyses of log C-reactive protein and conventional risk factors for coronary heart disease in the Emerging Risk Factors Collaboration, a collation of individual data from multiple prospective studies with an average follow-up duration of 9.8 years (dates varied). We derive risk prediction models using Cox proportional hazards regression analysis stratified by study and obtain estimates of risk discrimination, Harrell's concordance index, and Royston's discrimination measure within each study; we then combine the estimates across studies using a weighted meta-analysis. Various weighting approaches are compared and lead us to recommend using the number of events in each study. We also discuss the calculation of measures of reclassification for multiple studies. We further show that comparison of differences in predictive ability across subgroups should be based only on within-study information and that combining measures of risk discrimination from case-control studies and prospective studies is problematic. The concordance index and discrimination measure gave qualitatively similar results throughout. While the concordance index was very heterogeneous between studies, principally because of differing age ranges, the increments in the concordance index from adding log C-reactive protein to conventional risk factors were more homogeneous.

  19. Communication-based assessment of developmental age for young children with developmental disabilities.

    PubMed

    DeVeney, Shari L; Hoffman, Lesa; Cress, Cynthia J

    2012-06-01

    In this study, the authors compared a multiple-domain strategy for assessing developmental age of young children with developmental disabilities who were at risk for long-term reliance on augmentative and alternative communication (AAC) with a communication-based strategy composed of receptive language and communication indices that may be less affected by physically challenging tasks than traditional developmental age scores. Participants were 42 children (age 9-27 months) with developmental disabilities and who were at risk for long-term reliance on AAC. Children were assessed longitudinally in their homes at 3 occasions over 18 months using multiple-domain and communication-based measures. Confirmatory factor analysis examined dimensionality across the measures, and age-equivalence scores under each strategy were compared, where possible. The communication-based latent factor of developmental age demonstrated good reliability and was almost perfectly correlated with the multiple-domain latent factor. However, the mean age-equivalence score of the communication-based assessment significantly exceeded that of the multiple-domain assessment by 5.3 months across ages. Clinicians working with young children with developmental disabilities should consider a communication-based approach as an alternative developmental age assessment strategy for characterizing children's capabilities, identifying challenges, and developing interventions. A communication-based developmental age estimation is sufficiently reliable and may result in more valid inferences about developmental age for children whose developmental or cognitive age scores may otherwise be limited by their physical capabilities.

  20. Factors influencing recruitment of walleye and white bass to three distinct early ontogenetic stages

    USGS Publications Warehouse

    DeBoer, Jason A.; Pope, Kevin L.

    2015-01-01

    Determining the factors that influence recruitment to sequential ontogenetic stages is critical for understanding recruitment dynamics of fish and for effective management of sportfish, particularly in dynamic and unpredictable environments. We sampled walleye (Sander vitreus) and white bass (Morone chrysops) at 3 ontogenetic stages (age 0 during spring: ‘age-0 larval’; age 0 during autumn: ‘age-0 juvenile’; and age 1 during autumn: ‘age-1 juvenile’) from 3 reservoirs. We developed multiple linear regression models to describe factors influencing age-0 larval, age-0 juvenile and age-1 juvenile walleye and white bass abundance indices. Our models explained 40–80% (68 ± 9%; mean ± SE) and 71%–97% (81 ± 6%) of the variability in catch for walleye and white bass respectively. For walleye, gizzard shad were present in the candidate model sets for all three ontogenetic stages we assessed. For white bass, there was no unifying variable in all three stage-specific candidate model sets, although walleye abundance was present in two of the three white bass candidate model sets. We were able to determine several factors affecting walleye and white bass year-class strength at multiple ontogenetic stages; comprehensive analyses of factors influencing recruitment to multiple early ontogenetic stages are seemingly rare in the literature. Our models demonstrate the interdependency among early ontogenetic stages and the complexities involved with sportfish recruitment.

  1. Integrins as Modulators of Transforming Growth Factor Beta Signaling in Dermal Fibroblasts During Skin Regeneration After Injury.

    PubMed

    Boo, Stellar; Dagnino, Lina

    2013-06-01

    Abnormal wound repair results from disorders in granulation tissue remodeling, and can lead to hypertrophic scarring and fibrosis. Excessive scarring can compromise tissue function and decrease tissue resistance to additional injuries. The development of potential therapies to minimize scarring is, thus, necessary to address an important clinical problem. It has been clearly established that multiple cytokines and growth factors participate in the regulation of cutaneous wound healing. More recently, it has become apparent that these factors do not necessarily activate isolated signaling pathways. Rather, in some cases, there is cross-modulation of several cellular pathways involved in this process. Two of the key pathways that modulate each other during wound healing are activated by transforming growth factor-β and by extracellular matrix proteins acting through integrins. The pathogenesis of excessive scarring upon wound healing is not fully understood, as a result of the complexity of this process. However, the fact that many pathways combine to produce fibrosis provides multiple potential therapeutic targets. Some of them have been identified, such as focal adhesion kinase and integrin-linked kinase. Currently, a major challenge is to develop pharmacological inhibitors of these proteins with therapeutic value to promote efficient wound repair. The ability to better understand how different pathways crosstalk during wound repair and to identify and pharmacologically modulate key factors that contribute to the regulation of multiple wound-healing pathways could potentially provide effective therapeutic targets to decrease or prevent excessive scar formation and/or development of fibrosis.

  2. Organizational Justice and Physiological Coronary Heart Disease Risk Factors in Japanese Employees: a Cross-Sectional Study.

    PubMed

    Inoue, Akiomi; Kawakami, Norito; Eguchi, Hisashi; Miyaki, Koichi; Tsutsumi, Akizumi

    2015-12-01

    Growing evidence has shown that lack of organizational justice (i.e., procedural justice and interactional justice) is associated with coronary heart disease (CHD) while biological mechanisms underlying this association have not yet been fully clarified. The purpose of the present study was to investigate the cross-sectional association of organizational justice with physiological CHD risk factors (i.e., blood pressure, high-density lipoprotein [HDL] cholesterol, low-density lipoprotein [LDL] cholesterol, and triglyceride) in Japanese employees. Overall, 3598 male and 901 female employees from two manufacturing companies in Japan completed self-administered questionnaires measuring organizational justice, demographic characteristics, and lifestyle factors. They completed health checkup, which included blood pressure and serum lipid measurements. Multiple logistic regression analyses and trend tests were conducted. Among male employees, multiple logistic regression analyses and trend tests showed significant associations of low procedural justice and low interactional justice with high triglyceride (defined as 150 mg/dL or greater) after adjusting for demographic characteristics and lifestyle factors. Among female employees, trend tests showed significant dose-response relationship between low interactional justice and high LDL cholesterol (defined as 140 mg/dL or greater) while multiple logistic regression analysis showed only marginally significant or insignificant odds ratio of high LDL cholesterol among the low interactional justice group. Neither procedural justice nor interactional justice was associated with blood pressure or HDL cholesterol. Organizational justice may be an important psychosocial factor associated with increased triglyceride at least among Japanese male employees.

  3. Simulation Analysis of the Mutual Influence of the Stress Intensity Factor on the Multiple Blisters Caused by Hydrogen Induced Damage

    NASA Astrophysics Data System (ADS)

    Ji, Congwei; Zhang, Shaojie; Wang, Hehui

    2018-03-01

    Hydrogen blisters are taken as the research object by using the finite element software ABAQUS. The stress intensity factors of blister cracks are numerically calculated at varying depths and different edge distances for established three-dimensional finite element models of single-blister and double-blisters, respectively. The mutual influence of the stress intensity factors of the multiple blisters is obtained. It shows that the blister crack is easier to expand when the crack is closer to inner wall of the cylinder. What’s more, the crack growth rate increases firstly and then decreases as the increasing of the distance between two blisters cracks. The investigated result is of great reference value for predicting the trend of blister crack growth.

  4. AlInAsSb separate absorption, charge, and multiplication avalanche photodiodes

    NASA Astrophysics Data System (ADS)

    Ren, Min; Maddox, Scott J.; Woodson, Madison E.; Chen, Yaojia; Bank, Seth R.; Campbell, Joe C.

    2016-05-01

    We report AlxIn1-xAsySb1-y separate absorption, charge, and multiplication avalanche photodiodes (APDs) that operate in the short-wavelength infrared spectrum. They exhibit excess noise factor less or equal to that of Si and the low dark currents typical of III-V compound APDs.

  5. Wait-Time and Multiple Representation Levels in Chemistry Lessons

    ERIC Educational Resources Information Center

    Li, Winnie Sim Siew; Arshad, Mohammad Yusof

    2014-01-01

    Wait-time is an important aspect in a teaching and learning process, especially after the teacher has posed questions to students, as it is one of the factors in determining quality of students' responses. This article describes the practices of wait-time one after teacher's questions at multiple representation levels among twenty three chemistry…

  6. Stress, Behavior, and Children and Youth Who Are Deafblind

    ERIC Educational Resources Information Center

    Nelson, Catherine; Greenfield, Robin G.; Hyte, Holly A.; Shaffer, Jason P.

    2013-01-01

    Children and youth who are deafblind with multiple disabilities have several identified risk factors for experiencing toxic levels of stress, and such stress is known to impair physical, mental, and emotional health. This single-case multiple baseline study examined the frequency and duration of behaviors thought to indicate stress, the duration…

  7. Evidence-Based Assessment of Conduct Problems in Children and Adolescents

    ERIC Educational Resources Information Center

    McMahon, Robert J.; Frick, Paul J.

    2005-01-01

    This article provides a summary of research in 4 areas that have direct and important implications for evidence-based assessment of children and adolescents with conduct problems (CP): (a) the heterogeneity in types and severity of CP, (b) common comorbid conditions, (c) multiple risk factors associated with CP, and (d) multiple developmental…

  8. A Constructionist Discourse on Resilience: Multiple Contexts, Multiple Realities among At-Risk Children and Youth

    ERIC Educational Resources Information Center

    Ungar, Michael

    2004-01-01

    An ecological approach to the study of resilience, informed by Systems Theory and emphasizing predictable relationships between risk and protective factors, circular causality, and transactional processes, is inadequate to account for the diversity of people's experiences of resilience. In contrast, a constructionist interpretation of resilience…

  9. Speech and Language Therapists' Approaches to Communication Intervention with Children and Adults with Profound and Multiple Learning Disability

    ERIC Educational Resources Information Center

    Goldbart, Juliet; Chadwick, Darren; Buell, Susan

    2014-01-01

    Background: People with profound intellectual and multiple disabilities (PMLD) have communication impairments as one defining characteristic. Aims: To explore speech and language therapists' (SLTs) decision making in communication interventions for people with PMLD, in terms of the intervention approaches used, the factors informing the decisions…

  10. Measurement Invariance for Latent Constructs in Multiple Populations: A Critical View and Refocus

    ERIC Educational Resources Information Center

    Raykov, Tenko; Marcoulides, George A.; Li, Cheng-Hsien

    2012-01-01

    Popular measurement invariance testing procedures for latent constructs evaluated by multiple indicators in distinct populations are revisited and discussed. A frequently used test of factor loading invariance is shown to possess serious limitations that in general preclude it from accomplishing its goal of ascertaining this invariance. A process…

  11. Coh-Metrix Measures Text Characteristics at Multiple Levels of Language and Discourse

    ERIC Educational Resources Information Center

    Graesser, Arthur C.; McNamara, Danielle S.; Cai, Zhiqiang; Conley, Mark; Li, Haiying; Pennebaker, James

    2014-01-01

    Coh-Metrix analyzes texts on multiple measures of language and discourse that are aligned with multilevel theoretical frameworks of comprehension. Dozens of measures funnel into five major factors that systematically vary as a function of types of texts (e.g., narrative vs. informational) and grade level: narrativity, syntactic simplicity, word…

  12. Methoprene and temperature effects on caste differentiation and protein composition in the Formosan subterranean termite, Coptotermes formosanus

    USDA-ARS?s Scientific Manuscript database

    The utilization of multiple caste is a shared feature of many social insects. In termites, multiple extrinsic factors have been shown to impact caste differentiation; for example, temperature has been shown to increase soldier production. The objective of this investigation was to examine and corr...

  13. Visual Attention for Solving Multiple-Choice Science Problem: An Eye-Tracking Analysis

    ERIC Educational Resources Information Center

    Tsai, Meng-Jung; Hou, Huei-Tse; Lai, Meng-Lung; Liu, Wan-Yi; Yang, Fang-Ying

    2012-01-01

    This study employed an eye-tracking technique to examine students' visual attention when solving a multiple-choice science problem. Six university students participated in a problem-solving task to predict occurrences of landslide hazards from four images representing four combinations of four factors. Participants' responses and visual attention…

  14. Exercise and Quality of Life in Women with Multiple Sclerosis

    ERIC Educational Resources Information Center

    Giacobbi, Peter R., Jr.; Dietrich, Frederick; Larson, Rebecca; White, Lesley J.

    2012-01-01

    The purpose of this study was to evaluate perceptions of quality of life after a 4-month progressive resistance training program for individuals with multiple sclerosis (MS). A second purpose was to examine participants' views about factors that facilitated or impeded exercise behavior. Qualitative interviews were conducted with eight females…

  15. Preliminary Evidence that Self-Efficacy Predicts Physical Activity in Multiple Sclerosis

    ERIC Educational Resources Information Center

    Motl, Robert W.; McAuley, Edward; Doerksen, Shawna; Hu, Liang; Morris, Katherine S.

    2009-01-01

    Individuals with multiple sclerosis (MS) are less physically active than nondiseased people. One method for increasing physical activity levels involves the identification of factors that correlate with physical activity and that are modifiable by a well designed intervention. This study examined two types of self-efficacy as cross-sectional and…

  16. Internationally-Educated Health Professionals: A Distance Education Multiple Cultures Model

    ERIC Educational Resources Information Center

    Lum, Lillie

    2006-01-01

    Purpose: This paper aims to explore issues that must be addressed in post-secondary educational planning and delivery such that social cultural factors within the learning environment are recognized in ways that affirm the learner's cultural traditions. Design/methodology/approach: The adoption of a multiple cultures model of instructional design…

  17. Intelligence Assessment: Gardner Multiple Intelligence Theory as an Alternative

    ERIC Educational Resources Information Center

    Almeida, Leandro S.; Prieto, Maria Dolores; Ferreira, Aristides I.; Bermejo, Maria Rosario; Ferrando, Mercedes; Ferrandiz, Carmen

    2010-01-01

    In the multiple intelligence framework, newer and more contextualized cognitive tasks are suggested as alternative to more traditional psychometric tests. The purpose of this article is to examine whether or not these two types of instruments converge into a general factor of cognitive performance. Thus, the Battery of General and Differential…

  18. The Impact of Learning Multiple Foreign Languages on Using Metacognitive Reading Strategies

    ERIC Educational Resources Information Center

    Razi, Salim

    2008-01-01

    This study aims primarily to investigate the impact of learning multiple foreign languages on the use of metacognitive reading strategies (MRSs) by foreign language teaching (FLT) department students. A number of factors such as gender, hand preference, class, and programme with reference to their belief orientation were also involved in the…

  19. Brief Alcohol Interventions and Multiple Risk Factors in Primary Care

    ERIC Educational Resources Information Center

    Funderburk, Jennifer S.; Maisto, Stephen A.; Sugarman, Dawn E.

    2007-01-01

    Early identification and intervention of harmful/hazardous drinking in primary care are U.S. healthcare priorities. Traditionally, research has focused on designing interventions for patients in primary care who report hazardous/harmful alcohol use, even though it is likely for a patient to be at risk for multiple problems. This article has three…

  20. Respiratory dose assessment of inhaled particles: continuing progress

    EPA Science Inventory

    Internal dose is a key factor for determining the health risk ofinhaled pollutant particles on the one hand and the efficacy ofdrug inhalantsonthe other. Accurateestimation ofrespiratorydose, however, is a difficult task because multiple factors come to play roles in the process....

  1. Occupational Health Promotion Programs to Reduce Cardiovascular Risk.

    ERIC Educational Resources Information Center

    Glasgow, Russell E.; Terborg, James R.

    1988-01-01

    Surveys literature on worksite health promotion programs targeting cardiovascular risk factors. Reviews findings on health-risk appraisal, hypertension control, smoking cessation, weight reduction, exercise, and programs addressing multiple risk factors. Discusses current knowledge, highlights exemplary studies, and identifies problems and…

  2. Predicting Homophobic Behavior among Heterosexual Youth: Domain General and Sexual Orientation-Specific Factors at the Individual and Contextual Level

    ERIC Educational Resources Information Center

    Poteat, V. Paul; DiGiovanni, Craig D.; Scheer, Jillian R.

    2013-01-01

    As a form of bias-based harassment, homophobic behavior remains prominent in schools. Yet, little attention has been given to factors that underlie it, aside from bullying and sexual prejudice. Thus, we examined multiple domain general (empathy, perspective-taking, classroom respect norms) and sexual orientation-specific factors (sexual…

  3. Prospective Prediction of Functional Difficulties among Recently Separated Veterans

    DTIC Science & Technology

    2014-01-01

    while factors following separation from the military have a primary role in predicting functional difficulties during reintegration into civilian...and protective factors for functional difficulties among Veterans. In a sample of recently separated Marines, we used stepwise logistic and multiple...military, posttraumatic stress disorder, prospective, PTSD, reintegration, risk factors , Veterans, work functioning . INTRODUCTION Studies suggest that Iraq

  4. An Analysis of Multiple Factors Affecting Retention in Web-Based Community College Courses

    ERIC Educational Resources Information Center

    Doherty, William

    2006-01-01

    The current study examined four factors affecting retention in Web-based community college courses. Analyses were conducted on student demographics, student learning styles, course communication and external factors. The results suggest that Web-based courses are more attractive to busy students who are also more likely to fail or drop the course.…

  5. Manpower Planning, Occupational Education, and the Decision to Participate in the Labor Force. DASP Technical Paper No. 2.

    ERIC Educational Resources Information Center

    Kaufman, Jacob J.; Sumansky, John M.

    The report examines the multiplicity of factors which influence the labor market activity of the population and explores the implications of changes in those influential factors with regard to manpower and educational planning policy. The first section contains the introduction to the problem, summary of factors affecting labor force…

  6. Degree and Direction of Multiple Career Factors: Sex Differences and Construct Validity.

    ERIC Educational Resources Information Center

    Shaffer, Michal; And Others

    Personality, environment, and the interaction between them have been suggested as the major factors accounting for career development. Students (N=283) were asked to respond to 28 items on a recently revised self-report instrument, the Career Factor Checklist (CFC), in order to establish the construct validity of the revised CFC and to investigate…

  7. Making the Connection--Factors Influencing Implementation of Evidence Supported and Non-Evaluated Lifestyle Interventions in Healthcare: A Multiple Case Study

    ERIC Educational Resources Information Center

    van de Glind, Irene; Heinen, Maud; Geense, Wytske; Mesters, Ilse; Wensing, Michel; van Achterberg, Theo

    2015-01-01

    Many implementation barriers relate to lifestyle interventions (LIs) being developed by scientists. Exploring whether implementation of non-evaluated LIs is less complicated, might offer insight how to improve the use of effective interventions. This study aimed to identify influencing factors for implementation and compare factors between…

  8. Default Bayes Factors for Model Selection in Regression

    ERIC Educational Resources Information Center

    Rouder, Jeffrey N.; Morey, Richard D.

    2012-01-01

    In this article, we present a Bayes factor solution for inference in multiple regression. Bayes factors are principled measures of the relative evidence from data for various models or positions, including models that embed null hypotheses. In this regard, they may be used to state positive evidence for a lack of an effect, which is not possible…

  9. Exploratory Two-Level Analysis of Individual- and School-Level Factors on Truant Youth Emotional/Psychological Functioning

    ERIC Educational Resources Information Center

    Dembo, Richard; Wareham, Jennifer; Schmeidler, James; Winters, Ken C.

    2016-01-01

    Research on samples of truant adolescents is limited, with little known about mental health problems among truant youths. This study provided an exploratory, multilevel examination of mental health problems for a sample of 300 truant adolescents. Confirmatory factor analysis indicated a single factor of multiple mental health problems at the…

  10. Incidence of neutropenia and use of granulocyte colony-stimulating factors in multiple myeloma: is current clinical practice adequate?

    PubMed

    Leleu, Xavier; Gay, Francesca; Flament, Anne; Allcott, Kim; Delforge, Michel

    2018-03-01

    Although immunomodulatory drugs, alkylating agents, corticosteroids, protease inhibitors, and therapeutic monoclonal antibodies improve multiple myeloma outcomes, treatment burden is still an issue. Neutropenia is a known complication of cytotoxic cancer therapy and is often associated with infections; it is an important consideration in myeloma given the fact that patients often have a weakened immune system. The risk of febrile neutropenia increases with severe and persisting neutropenia. Recombinant granulocyte colony-stimulating factors (G-CSFs) are commonly used to reduce the incidence, duration, and severity of febrile neutropenia. Here, we review the risk and management of neutropenia associated with new and commonly used anti-myeloma agents. Few papers report the use of G-CSF in patients with multiple myeloma receiving anti-cancer treatments, and fewer describe whether G-CSF was beneficial. None of the identified studies reported G-CSF primary prophylaxis. Further studies are warranted to evaluate the need for G-CSF prophylaxis in multiple myeloma. Prophylaxis may be particularly useful in patients at high risk of prolonged severe neutropenia.

  11. Update on Multiple Ovulations in Dairy Cattle

    PubMed Central

    Macmillan, Kira; Kastelic, John P.

    2018-01-01

    Simple Summary Multiple ovulations (MOV) in cattle can lead to twin pregnancies, which negatively affects the health, production, and reproduction of cows. Despite many studies, the causal mechanisms behind MOV are still not well understood. There is a general agreement that MOV are more likely during periods of low progesterone (P4), which may increase the luteinizing hormone (LH) release at the time of selection, resulting in more than one follicle becoming dominant. The MOV rate also increases in older cows and when the selection of a dominant follicle occurs concurrently with a high milk yield. Additional risk factors for MOV are ovarian cysts, diet, season, and genetics. A better understanding of the mechanisms underlying MOV may help to mitigate twinning, perhaps through the appropriate reproductive management protocols or genetic selection. Abstract This review updates the causal mechanisms and risk factors for multiple ovulations (MOV) in cattle. Clearly, MOV can lead to twin pregnancies, which negatively affects the health, production, and reproduction of cows. Therefore, a better understanding of the factors causing MOV may help to reduce twinning. Multiple ovulations occur after two or more follicles deviate and achieve codominance. The MOV rate is influenced by a complex network of hormones. For example, MOV is more common during periods of low progesterone (P4), that is, in anovulatory cattle or when luteolysis coincides with the selection of the future ovulatory follicle. There is also strong evidence for the luteinizing hormone (LH) being the primary factor leading to codominance, as high P4 concentrations suppress the transient LH surges and can reduce the ovulation rate in cattle or even inhibit deviation. Rates of MOV are increased in older and higher-producing dairy cows. Increased milk production and dry matter intake (DMI) increases hormone clearance, including P4; however, the association between milk yield and MOV has not been consistent. Additional risk factors for MOV include ovarian cysts, diet, season, and genetics. PMID:29695075

  12. Plasma granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor levels in critical illness including sepsis and septic shock: relation to disease severity, multiple organ dysfunction, and mortality.

    PubMed

    Presneill, J J; Waring, P M; Layton, J E; Maher, D W; Cebon, J; Harley, N S; Wilson, J W; Cade, J F

    2000-07-01

    To define the circulating levels of granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) during critical illness and to determine their relationship to the severity of illness as measured by the Acute Physiology and Chronic Health Evaluation (APACHE) II score, the development of multiple organ dysfunction, or mortality. Prospective cohort study. University hospital intensive care unit. A total of 82 critically ill adult patients in four clinically defined groups, namely septic shock (n = 29), sepsis without shock (n = 17), shock without sepsis (n = 22), and nonseptic, nonshock controls (n = 14). None. During day 1 of septic shock, peak plasma levels of G-CSF, interleukin (IL)-6, and leukemia inhibitory factor (LIF), but not GM-CSF, were greater than in sepsis or shock alone (p < .001), and were correlated among themselves (rs = 0.44-0.77; p < .02) and with the APACHE II score (rs = 0.25-0.40; p = .03 to .18). G-CSF, IL-6, and UF, and sepsis, shock, septic shock, and APACHE II scores were strongly associated with organ dysfunction or 5-day mortality by univariate analysis. However, multiple logistic regression analysis showed that only septic shock remained significantly associated with organ dysfunction and only APACHE II scores and shock with 5-day mortality. Similarly, peak G-CSF, IL-6, and LIF were poorly predictive of 30-day mortality. Plasma levels of G-CSF, IL-6, and LIF are greatly elevated in critical illness, including septic shock, and are correlated with one another and with the severity of illness. However, they are not independently predictive of mortality, or the development of multiple organ dysfunction. GM-CSF was rarely elevated, suggesting different roles for G-CSF and GM-CSF in human septic shock.

  13. Winner of the society for biomaterials student award in the Ph.D. category for the annual meeting of the society for biomaterials, april 11-14, 2018, Atlanta, GA: Development of a bimodal, in situ crosslinking method to achieve multifactor release from electrospun gelatin.

    PubMed

    Kishan, Alysha; Walker, Taneidra; Sears, Nick; Wilems, Thomas; Cosgriff-Hernandez, Elizabeth

    2018-05-01

    To better mimic native tissue microenvironments, current efforts have moved beyond single growth factor delivery to more complex multiple growth factor delivery with distinct release profiles. Electrospun gelatin, a widely investigated drug delivery vehicle, requires postprocessing crosslinking techniques that generate a mesh with uniform crosslinking density, limiting the ability to deliver multiple factors at different rates. Herein, we describe a method to independently control release of multiple factors from a single electrospun gelatin mesh. Two in situ crosslinking modalities, photocrosslinking of methacyrlated gelatin and reactive crosslinking of gelatin with a diisocyanate, are coelectrospun to generate distinct fiber populations with different crosslinking chemistry and density in a single mesh. The photocrosslinked gelatin-methacrylate resulted in a relatively rapid release of a model protein (48 ± 12% at day 1, 96 ± 3% at day 10) due to diffusion of embedded protein from the crosslinked fibers. The reactive crosslinking system displayed a more sustained release (7 ± 5% at day 1, 33 ± 2% at day 10) that was attributed to the conjugation of protein to gelatin with the diisocyanate, requiring degradation of gelatin prior to diffusion out of the fibers. Both modalities displayed tunable release profiles. Subsequent release studies of a cospun mesh with two different crosslinked fiber populations confirmed that the cospun mesh displayed multifactor release with independent release profiles. Overall, this bimodal, in situ crosslinking approach enables the delivery of multiple factors with distinct release kinetics from a single mesh and is expected to have broad utility in tissue engineering. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1155-1164, 2018. © 2018 Wiley Periodicals, Inc.

  14. Non-coding Double-stranded RNA and Antimicrobial Peptide LL-37 Induce Growth Factor Expression from Keratinocytes and Endothelial Cells*

    PubMed Central

    Adase, Christopher A.; Borkowski, Andrew W.; Zhang, Ling-juan; Williams, Michael R.; Sato, Emi; Sanford, James A.

    2016-01-01

    A critical function for skin is that when damaged it must simultaneously identify the nature of the injury, repair barrier function, and limit the intrusion of pathogenic organisms. These needs are carried out through the detection of damage-associated molecular patterns (DAMPs) and a response that includes secretion of cytokines, chemokines, growth factors, and antimicrobial peptides (AMPs). In this study, we analyzed how non-coding double-stranded RNA (dsRNAs) act as a DAMP in the skin and how the human cathelicidin AMP LL-37 might influence growth factor production in response to this DAMP. dsRNA alone significantly increased the expression of multiple growth factors in keratinocytes, endothelial cells, and fibroblasts. Furthermore, RNA sequencing transcriptome analysis found that multiple growth factors increase when cells are exposed to both LL-37 and dsRNA, a condition that mimics normal wounding. Quantitative PCR and/or ELISA validated that growth factors expressed by keratinocytes in these conditions included, but were not limited to, basic fibroblast growth factor (FGF2), heparin-binding EGF-like growth factor (HBEGF), vascular endothelial growth factor C (VEGFC), betacellulin (BTC), EGF, epiregulin (EREG), and other members of the transforming growth factor β superfamily. These results identify a novel role for DAMPs and AMPs in the stimulation of repair and highlight the complex interactions involved in the wound environment. PMID:27048655

  15. Psychological factors are associated with subjective cognitive complaints 2 months post-stroke.

    PubMed

    Nijsse, Britta; van Heugten, Caroline M; van Mierlo, Marloes L; Post, Marcel W M; de Kort, Paul L M; Visser-Meily, Johanna M A

    2017-01-01

    The aim of this study was to investigate which psychological factors are related to post-stroke subjective cognitive complaints, taking into account the influence of demographic and stroke-related characteristics, cognitive deficits and emotional problems. In this cross-sectional study, 350 patients were assessed at 2 months post-stroke, using the Checklist for Cognitive and Emotional consequences following stroke (CLCE-24) to identify cognitive complaints. Psychological factors were: proactive coping, passive coping, self-efficacy, optimism, pessimism, extraversion, and neuroticism. Associations between CLCE-24 cognition score and psychological factors, emotional problems (depressive symptoms and anxiety), cognitive deficits, and demographic and stroke characteristics were examined using Spearman correlations and multiple regression analyses. Results showed that 2 months post-stroke, 270 patients (68.4%) reported at least one cognitive complaint. Age, sex, presence of recurrent stroke(s), comorbidity, cognitive deficits, depressive symptoms, anxiety, and all psychological factors were significantly associated with the CLCE-24 cognition score in bivariate analyses. Multiple regression analysis showed that psychological factors explained 34.7% of the variance of cognitive complaints independently, and 8.5% (p < .001) after taking all other factors into account. Of all psychological factors, proactive coping was independently associated with cognitive complaints (p < .001), showing that more proactive coping related to less cognitive complaints. Because cognitive complaints are common after stroke and are associated with psychological factors, it is important to focus on these factors in rehabilitation programmes.

  16. Internal and external environmental factors affecting the performance of hospital-based home nursing care.

    PubMed

    Noh, J-W; Kwon, Y-D; Yoon, S-J; Hwang, J-I

    2011-06-01

    Numerous studies on HNC services have been carried out by signifying their needs, efficiency and effectiveness. However, no study has ever been performed to determine the critical factors associated with HNC's positive results despite the deluge of positive studies on the service. This study included all of the 89 training hospitals that were practising HNC service in Korea as of November 2006. The input factors affecting the performance were classified as either internal or external environmental factors. This analysis was conducted to understand the impact that the corresponding factors had on performance. Data were analysed by using multiple linear regressions. The internal and external environment variables affected the performance of HNC based on univariate analysis. The meaningful variables were internal environmental factors. Specifically, managerial resource (the number of operating beds and the outpatient/inpatient ratio) were meaningful when the multiple linear regression analysis was performed. Indeed, the importance of organizational culture (the passion of HNC nurses) was significant. This study, considering the limited market size of Korea, illustrates that the critical factor for the development of hospital-led HNC lies with internal environmental factors rather than external ones. Among the internal environmental factors, the hospitals' managerial resource-related factors (specifically, the passion of nurses) were the most important contributing element. © 2011 The Authors. International Nursing Review © 2011 International Council of Nurses.

  17. Repeatedly measured material and behavioral factors changed the explanation of socioeconomic inequalities in all-cause mortality.

    PubMed

    Oude Groeniger, Joost; Kamphuis, Carlijn B; Mackenbach, Johan P; van Lenthe, Frank J

    2017-11-01

    We examined whether using repeatedly measured material and behavioral factors contributed differently to socioeconomic inequalities in all-cause mortality compared to one baseline measurement. Data from the Dutch prospective GLOBE cohort were linked to mortality register data (1991-2013; N = 4,851). Socioeconomic position was measured at baseline by educational level and occupation. Material factors (financial difficulties, housing tenure, health insurance) and behavioral factors (smoking, leisure time physical activity, sports participation, and body mass index) were self-reported in 1991, 1997, and 2004. Cox proportional hazards regression and bootstrap methods were used to examine the contribution of baseline-only and time-varying risk factors to socioeconomic inequalities in mortality. Men and women in the lowest educational and occupational groups were at an increased risk of dying compared to the highest groups. The contribution of material factors to socioeconomic inequalities in mortality was smaller when multiple instead of baseline-only measurements were used (25%-65% vs. 49%-93%). The contribution of behavioral factors was larger when multiple measurements were used (39%-51% vs. 19%-40%). Inclusion of time-dependent risk factors contributes to understanding socioeconomic inequalities in mortality, but careful examination of the underlying mechanisms and suitability of the model is required. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Comparative study on neutronics characteristics of a 1500 MWe metal fuel sodium-cooled fast reactor

    DOE PAGES

    Ohgama, Kazuya; Aliberti, Gerardo; Stauff, Nicolas E.; ...

    2017-02-28

    Under the cooperative effort of the Civil Nuclear Energy R&D Working Group within the framework of the U.S.-Japan bilateral, Argonne National Laboratory (ANL) and Japan Atomic Energy Agency (JAEA) have been performing benchmark study using Japan Sodium-cooled Fast Reactor (JSFR) design with metal fuel. In this benchmark study, core characteristic parameters at the beginning of cycle were evaluated by the best estimate deterministic and stochastic methodologies of ANL and JAEA. The results obtained by both institutions show a good agreement with less than 200 pcm of discrepancy on the neutron multiplication factor, and less than 3% of discrepancy on themore » sodium void reactivity, Doppler reactivity, and control rod worth. The results by the stochastic and deterministic approaches were compared in each party to investigate impacts of the deterministic approximation and to understand potential variations in the results due to different calculation methodologies employed. From the detailed analysis of methodologies, it was found that the good agreement in multiplication factor from the deterministic calculations comes from the cancellation of the differences on the methodology (0.4%) and nuclear data (0.6%). The different treatment in reflector cross section generation was estimated as the major cause of the discrepancy between the multiplication factors by the JAEA and ANL deterministic methodologies. Impacts of the nuclear data libraries were also investigated using a sensitivity analysis methodology. Furthermore, the differences on the inelastic scattering cross sections of U-238, ν values and fission cross sections of Pu-239 and µ-average of Na-23 are the major contributors to the difference on the multiplication factors.« less

  19. Evolutionary profiles derived from the QR factorization of multiple structural alignments gives an economy of information.

    PubMed

    O'Donoghue, Patrick; Luthey-Schulten, Zaida

    2005-02-25

    We present a new algorithm, based on the multidimensional QR factorization, to remove redundancy from a multiple structural alignment by choosing representative protein structures that best preserve the phylogenetic tree topology of the homologous group. The classical QR factorization with pivoting, developed as a fast numerical solution to eigenvalue and linear least-squares problems of the form Ax=b, was designed to re-order the columns of A by increasing linear dependence. Removing the most linear dependent columns from A leads to the formation of a minimal basis set which well spans the phase space of the problem at hand. By recasting the problem of redundancy in multiple structural alignments into this framework, in which the matrix A now describes the multiple alignment, we adapted the QR factorization to produce a minimal basis set of protein structures which best spans the evolutionary (phase) space. The non-redundant and representative profiles obtained from this procedure, termed evolutionary profiles, are shown in initial results to outperform well-tested profiles in homology detection searches over a large sequence database. A measure of structural similarity between homologous proteins, Q(H), is presented. By properly accounting for the effect and presence of gaps, a phylogenetic tree computed using this metric is shown to be congruent with the maximum-likelihood sequence-based phylogeny. The results indicate that evolutionary information is indeed recoverable from the comparative analysis of protein structure alone. Applications of the QR ordering and this structural similarity metric to analyze the evolution of structure among key, universally distributed proteins involved in translation, and to the selection of representatives from an ensemble of NMR structures are also discussed.

  20. Multivariate meta-analysis of prognostic factor studies with multiple cut-points and/or methods of measurement.

    PubMed

    Riley, Richard D; Elia, Eleni G; Malin, Gemma; Hemming, Karla; Price, Malcolm P

    2015-07-30

    A prognostic factor is any measure that is associated with the risk of future health outcomes in those with existing disease. Often, the prognostic ability of a factor is evaluated in multiple studies. However, meta-analysis is difficult because primary studies often use different methods of measurement and/or different cut-points to dichotomise continuous factors into 'high' and 'low' groups; selective reporting is also common. We illustrate how multivariate random effects meta-analysis models can accommodate multiple prognostic effect estimates from the same study, relating to multiple cut-points and/or methods of measurement. The models account for within-study and between-study correlations, which utilises more information and reduces the impact of unreported cut-points and/or measurement methods in some studies. The applicability of the approach is improved with individual participant data and by assuming a functional relationship between prognostic effect and cut-point to reduce the number of unknown parameters. The models provide important inferential results for each cut-point and method of measurement, including the summary prognostic effect, the between-study variance and a 95% prediction interval for the prognostic effect in new populations. Two applications are presented. The first reveals that, in a multivariate meta-analysis using published results, the Apgar score is prognostic of neonatal mortality but effect sizes are smaller at most cut-points than previously thought. In the second, a multivariate meta-analysis of two methods of measurement provides weak evidence that microvessel density is prognostic of mortality in lung cancer, even when individual participant data are available so that a continuous prognostic trend is examined (rather than cut-points). © 2015 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

Top