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Sample records for affect multiple steps

  1. A dynamic RNA loop in an IRES affects multiple steps of elongation factor-mediated translation initiation

    PubMed Central

    Ruehle, Marisa D; Zhang, Haibo; Sheridan, Ryan M; Mitra, Somdeb; Chen, Yuanwei; Gonzalez, Ruben L; Cooperman, Barry S; Kieft, Jeffrey S

    2015-01-01

    Internal ribosome entry sites (IRESs) are powerful model systems to understand how the translation machinery can be manipulated by structured RNAs and for exploring inherent features of ribosome function. The intergenic region (IGR) IRESs from the Dicistroviridae family of viruses are structured RNAs that bind directly to the ribosome and initiate translation by co-opting the translation elongation cycle. These IRESs require an RNA pseudoknot that mimics a codon-anticodon interaction and contains a conformationally dynamic loop. We explored the role of this loop and found that both the length and sequence are essential for translation in different types of IGR IRESs and from diverse viruses. We found that loop 3 affects two discrete elongation factor-dependent steps in the IRES initiation mechanism. Our results show how the IRES directs multiple steps after 80S ribosome placement and highlights the often underappreciated significance of discrete conformationally dynamic elements within the context of structured RNAs. DOI: http://dx.doi.org/10.7554/eLife.08146.001 PMID:26523395

  2. Multiple stage miniature stepping motor

    DOEpatents

    Niven, William A.; Shikany, S. David; Shira, Michael L.

    1981-01-01

    A stepping motor comprising a plurality of stages which may be selectively activated to effect stepping movement of the motor, and which are mounted along a common rotor shaft to achieve considerable reduction in motor size and minimum diameter, whereby sequential activation of the stages results in successive rotor steps with direction being determined by the particular activating sequence followed.

  3. Three Steps to Mastering Multiplication Facts

    ERIC Educational Resources Information Center

    Kling, Gina; Bay-Williams, Jennifer M.

    2015-01-01

    "That was the day I decided I was bad at math." Countless times, preservice and in-service teachers make statements such as this after sharing vivid memories of learning multiplication facts. Timed tests; public competitive games, such as Around the World; and visible displays of who has and has not mastered groups of facts still…

  4. Small RAB GTPases Regulate Multiple Steps of Mitosis

    PubMed Central

    Miserey-Lenkei, Stéphanie; Colombo, María I.

    2016-01-01

    GTPases of the RAB family are key regulators of multiple steps of membrane trafficking. Several members of the RAB GTPase family have been implicated in mitotic progression. In this review, we will first focus on the function of endosome-associated RAB GTPases reported in early steps of mitosis, spindle pole maturation, and during cytokinesis. Second, we will discuss the role of Golgi-associated RAB GTPases at the metaphase/anaphase transition and during cytokinesis. PMID:26925400

  5. Multiple rate-determining steps for nonideal and fractal kinetics.

    PubMed

    Vlad, Marcel O; Popa, Vlad T; Segal, E; Ross, John

    2005-02-17

    We show that the kinetic model of a single rate-determining step in a reaction mechanism can be extended to systems with multiple overall reactions for which the elementary reactions obey nonideal or fractal kinetics. The following assumptions are necessary: (1) The system studied is either closed or open, but no constraints exist preventing the evolution toward equilibrium. (2) Elementary reactions occur in pairs of forward and backward steps. (3) The kinetics of the elementary steps are either nonideal or fractal and are compatible with equilibrium thermodynamics. (4) The number of reaction routes is identical with the number of rate-determining steps. If these hypotheses are valid, then the overall reaction rates can be explicitly evaluated: they have a form similar to the kinetic equations for the elementary reactions and the apparent reaction orders and fractal coefficients can be expressed analytically in terms of the kinetic parameters of the elementary reactions. We derive a set of relationships which connect the equilibrium constants of the reaction routes, the corresponding overall rate coefficients, and the stoichiometric numbers of the rate-determining steps. We also derive a set of generalized Boreskov relations among the apparent activation energies of the forward and backward overall processes, the corresponding reaction enthalpies, and the stoichiometric coefficients of the rate-determining steps. If the elementary reactions obey fractal kinetics, the same is true for the rate-determining steps. The fractal exponents of the forward and backward overall reactions are linear combinations of the fractal exponents of the fractal elementary reactions. Similar to the theory of single rate-determining steps, our approach can be used for selecting suitable reaction mechanisms from experimental data.

  6. Arousal and exposure duration affect forward step initiation

    PubMed Central

    Bouman, Daniëlle; Stins, John F.; Beek, Peter J.

    2015-01-01

    Emotion influences parameters of goal-directed whole-body movements in several ways. For instance, previous research has shown that approaching (moving toward) pleasant stimuli is easier compared to approaching unpleasant stimuli. However, some studies found that when emotional pictures are viewed for a longer time, approaching unpleasant stimuli may in fact be facilitated. The effect of viewing duration may have modulated whole-body approach movement in previous research but this has not been investigated to date. In the current study, participants initiated a step forward after viewing neutral, high-arousal pleasant and high-arousal unpleasant stimuli. The viewing duration of the stimuli was set to seven different durations, varying from 100 to 4000 ms. Valence and arousal scores were collected for all stimuli. The results indicate that both viewing duration and the arousal of the stimuli influence kinematic parameters in forward gait initiation. Specifically, longer viewing duration, compared to shorter viewing duration, (a) diminished the step length and peak velocity in both neutral and emotional stimuli, (b) increased reaction time in neutral stimuli and, (c) decreased reaction time in pleasant and unpleasant stimuli. Strikingly, no differences were found between high-arousal pleasant and high-arousal unpleasant stimuli. In other words, the valence of the stimuli did not influence kinematic parameters of forward step initiation. Instead the arousal level (neutral: low; pleasant and unpleasant: high) explained the variance found in the results. The kinematics of forward gait initiation seemed to be reflected in the subjective arousal scores, but not the valence scores. So it seems arousal affects forward gait initiation parameters more strongly than valence. In addition, longer viewing duration seemed to cause diminished alertness, affecting GI parameters. These results shed new light on the prevailing theoretical interpretations regarding approach motivation

  7. WNT/β-Catenin Signaling Regulates Multiple Steps of Myogenesis by Regulating Step-Specific Targets

    PubMed Central

    Suzuki, Akiko; Pelikan, Richard C.

    2015-01-01

    Molecules involved in WNT/β-catenin signaling show specific spatiotemporal expression and play vital roles in myogenesis; however, it is still largely unknown how WNT/β-catenin signaling regulates each step of myogenesis. Here, we show that WNT/β-catenin signaling can control diverse biological processes of myogenesis by regulating step-specific molecules. In order to identify the temporally specific roles of WNT/β-catenin signaling molecules in muscle development and homeostasis, we used in vitro culture systems for both primary mouse myoblasts and C2C12 cells, which can differentiate into myofibers. We found that a blockade of WNT/β-catenin signaling in the proliferating cells decreases proliferation activity, but does not induce cell death, through the regulation of genes cyclin A2 (Ccna2) and cell division cycle 25C (Cdc25c). During muscle differentiation, the inhibition of WNT/β-catenin signaling blocks myoblast fusion through the inhibition of the Fermitin family homolog 2 (Fermt2) gene. Blocking WNT/β-catenin signaling in the well-differentiated myofibers results in the failure of maintenance of their structure by disruption of cadherin/β-catenin/actin complex formation, which plays a crucial role in connecting a myofiber's cytoskeleton to the surrounding extracellular matrix. Thus, our results indicate that WNT/β-catenin signaling can regulate multiple steps of myogenesis, including cell proliferation, myoblast fusion, and homeostasis, by targeting step-specific molecules. PMID:25755281

  8. WNT/β-Catenin Signaling Regulates Multiple Steps of Myogenesis by Regulating Step-Specific Targets.

    PubMed

    Suzuki, Akiko; Pelikan, Richard C; Iwata, Junichi

    2015-05-01

    Molecules involved in WNT/β-catenin signaling show specific spatiotemporal expression and play vital roles in myogenesis; however, it is still largely unknown how WNT/β-catenin signaling regulates each step of myogenesis. Here, we show that WNT/β-catenin signaling can control diverse biological processes of myogenesis by regulating step-specific molecules. In order to identify the temporally specific roles of WNT/β-catenin signaling molecules in muscle development and homeostasis, we used in vitro culture systems for both primary mouse myoblasts and C2C12 cells, which can differentiate into myofibers. We found that a blockade of WNT/β-catenin signaling in the proliferating cells decreases proliferation activity, but does not induce cell death, through the regulation of genes cyclin A2 (Ccna2) and cell division cycle 25C (Cdc25c). During muscle differentiation, the inhibition of WNT/β-catenin signaling blocks myoblast fusion through the inhibition of the Fermitin family homolog 2 (Fermt2) gene. Blocking WNT/β-catenin signaling in the well-differentiated myofibers results in the failure of maintenance of their structure by disruption of cadherin/β-catenin/actin complex formation, which plays a crucial role in connecting a myofiber's cytoskeleton to the surrounding extracellular matrix. Thus, our results indicate that WNT/β-catenin signaling can regulate multiple steps of myogenesis, including cell proliferation, myoblast fusion, and homeostasis, by targeting step-specific molecules.

  9. Multiple time step integrators in ab initio molecular dynamics

    SciTech Connect

    Luehr, Nathan; Martínez, Todd J.; Markland, Thomas E.

    2014-02-28

    Multiple time-scale algorithms exploit the natural separation of time-scales in chemical systems to greatly accelerate the efficiency of molecular dynamics simulations. Although the utility of these methods in systems where the interactions are described by empirical potentials is now well established, their application to ab initio molecular dynamics calculations has been limited by difficulties associated with splitting the ab initio potential into fast and slowly varying components. Here we present two schemes that enable efficient time-scale separation in ab initio calculations: one based on fragment decomposition and the other on range separation of the Coulomb operator in the electronic Hamiltonian. We demonstrate for both water clusters and a solvated hydroxide ion that multiple time-scale molecular dynamics allows for outer time steps of 2.5 fs, which are as large as those obtained when such schemes are applied to empirical potentials, while still allowing for bonds to be broken and reformed throughout the dynamics. This permits computational speedups of up to 4.4x, compared to standard Born-Oppenheimer ab initio molecular dynamics with a 0.5 fs time step, while maintaining the same energy conservation and accuracy.

  10. Efficient multiple time-stepping algorithms of higher order

    NASA Astrophysics Data System (ADS)

    Demirel, Abdullah; Niegemann, Jens; Busch, Kurt; Hochbruck, Marlis

    2015-03-01

    Multiple time-stepping (MTS) algorithms allow to efficiently integrate large systems of ordinary differential equations, where a few stiff terms restrict the timestep of an otherwise non-stiff system. In this work, we discuss a flexible class of MTS techniques, based on multistep methods. Our approach contains several popular methods as special cases and it allows for the easy construction of novel and efficient higher-order MTS schemes. In addition, we demonstrate how to adapt the stability contour of the non-stiff time-integration to the physical system at hand. This allows significantly larger timesteps when compared to previously known multistep MTS approaches. As an example, we derive novel predictor-corrector (PCMTS) schemes specifically optimized for the time-integration of damped wave equations on locally refined meshes. In a set of numerical experiments, we demonstrate the performance of our scheme on discontinuous Galerkin time-domain (DGTD) simulations of Maxwell's equations.

  11. The Effects of Multiple-Step and Single-Step Directions on Fourth and Fifth Grade Students' Grammar Assessment Performance

    ERIC Educational Resources Information Center

    Mazerik, Matthew B.

    2006-01-01

    The mean scores of English Language Learners (ELL) and English Only (EO) students in 4th and 5th grade (N = 110), across the teacher-administered Grammar Skills Test, were examined for differences in participants' scores on assessments containing single-step directions and assessments containing multiple-step directions. The results indicated no…

  12. Steps in Cu(111) thin films affect graphene growth kinetics

    NASA Astrophysics Data System (ADS)

    Miller, David L.; Gannett, Will; Keller, Mark W.

    2014-03-01

    The kinetics of chemical vapor deposition of graphene on Cu substrates depend on the relative rates of C diffusion on the surface, C attachment to graphene islands, and removal of C from the surface or from graphene islands by etching processes involving H atoms. Using Cu(111) thin films with centimeter-sized grains, we have grown graphene under a variety of conditions and examined the edges of graphene islands with SEM and AFM. The Cu surface shows a series of regular steps, roughly 2 nm in height, and the graphene islands are diamond-shaped with faster growth along the edges of Cu steps. In contrast, growth on polycrystalline Cu foils under the same conditions shows hexagonal graphene islands with smooth edges.

  13. [Risk of affective disorder in multiple sclerosis].

    PubMed

    Stenager, Elsebeth Nylev; Stage, Kurt Bjerregaard; Stenager, Egon

    2011-01-10

    An increased risk for depression has been found in multiple sclerosis (MS). The purpose of the present study has been to give suggestions to guidelines for diagnosis and treatment of depression in MS in Denmark based on the international literature and recommendations. The method was a review of the relevant literature. The study recommends assessment of all MS patients for depression. Treatment of depression with serotonin reuptake inhibitors and/or cognitive behavioural therapy is recommended, depending on the severity of the illness. Caution is recommended in patients receiving beta interferon treatment.

  14. Step by Step: Biology Undergraduates' Problem-Solving Procedures during Multiple-Choice Assessment

    ERIC Educational Resources Information Center

    Prevost, Luanna B.; Lemons, Paula P.

    2016-01-01

    This study uses the theoretical framework of domain-specific problem solving to explore the procedures students use to solve multiple-choice problems about biology concepts. We designed several multiple-choice problems and administered them on four exams. We trained students to produce written descriptions of how they solved the problem, and this…

  15. [Affective and psychotic disorders in multiple sclerosis].

    PubMed

    Pozuelo-Moyano, Beatriz; Benito-León, Julián

    2015-12-01

    Introduccion. La esclerosis multiple (EM) es la segunda causa mas importante de discapacidad de origen neurologico en los adultos jovenes. Tanto la sintomatologia fisica como la psiquiatrica (trastornos afectivos y psicoticos) impactan de manera negativa en la calidad de vida relacionada con la salud de los pacientes con EM. Objetivo. Elucidar de modo critico la prevalencia y la patogenia de los sintomas afectivos y psicoticos presentes en la EM. Desarrollo. Se incluye una actualizacion de los estudios publicados mas significativos que han analizado la prevalencia y la patogenia de la sintomatologia afectiva y psicotica en los pacientes con EM. Para explorar la asociacion entre los sintomas afectivos y psicoticos con la EM se ha revisado la evidencia disponible hasta el momento. Conclusiones. La depresion es el trastorno psiquiatrico mas frecuente en la EM. Es necesaria mas investigacion para elucidar los mecanismos subyacentes que pueden provocar sintomas afectivos y psicoticos en la EM. El control de dichos sintomas en los pacientes de EM podria mejorar su calidad de vida relacionada con la salud.

  16. A multiple step random walk Monte Carlo method for heat conduction involving distributed heat sources

    NASA Astrophysics Data System (ADS)

    Naraghi, M. H. N.; Chung, B. T. F.

    1982-06-01

    A multiple step fixed random walk Monte Carlo method for solving heat conduction in solids with distributed internal heat sources is developed. In this method, the probability that a walker reaches a point a few steps away is calculated analytically and is stored in the computer. Instead of moving to the immediate neighboring point the walker is allowed to jump several steps further. The present multiple step random walk technique can be applied to both conventional Monte Carlo and the Exodus methods. Numerical results indicate that the present method compares well with finite difference solutions while the computation speed is much faster than that of single step Exodus and conventional Monte Carlo methods.

  17. Multiple-time-stepping generalized hybrid Monte Carlo methods

    SciTech Connect

    Escribano, Bruno; Akhmatskaya, Elena; Reich, Sebastian; Azpiroz, Jon M.

    2015-01-01

    Performance of the generalized shadow hybrid Monte Carlo (GSHMC) method [1], which proved to be superior in sampling efficiency over its predecessors [2–4], molecular dynamics and hybrid Monte Carlo, can be further improved by combining it with multi-time-stepping (MTS) and mollification of slow forces. We demonstrate that the comparatively simple modifications of the method not only lead to better performance of GSHMC itself but also allow for beating the best performed methods, which use the similar force splitting schemes. In addition we show that the same ideas can be successfully applied to the conventional generalized hybrid Monte Carlo method (GHMC). The resulting methods, MTS-GHMC and MTS-GSHMC, provide accurate reproduction of thermodynamic and dynamical properties, exact temperature control during simulation and computational robustness and efficiency. MTS-GHMC uses a generalized momentum update to achieve weak stochastic stabilization to the molecular dynamics (MD) integrator. MTS-GSHMC adds the use of a shadow (modified) Hamiltonian to filter the MD trajectories in the HMC scheme. We introduce a new shadow Hamiltonian formulation adapted to force-splitting methods. The use of such Hamiltonians improves the acceptance rate of trajectories and has a strong impact on the sampling efficiency of the method. Both methods were implemented in the open-source MD package ProtoMol and were tested on a water and a protein systems. Results were compared to those obtained using a Langevin Molly (LM) method [5] on the same systems. The test results demonstrate the superiority of the new methods over LM in terms of stability, accuracy and sampling efficiency. This suggests that putting the MTS approach in the framework of hybrid Monte Carlo and using the natural stochasticity offered by the generalized hybrid Monte Carlo lead to improving stability of MTS and allow for achieving larger step sizes in the simulation of complex systems.

  18. A multiple shift QR-step for structured rank matrices

    NASA Astrophysics Data System (ADS)

    Vandebril, Raf; van Barel, Marc; Mastronardi, Nicola

    2010-01-01

    Eigenvalue computations for structured rank matrices are the subject of many investigations nowadays. There exist methods for transforming matrices into structured rank form, QR-algorithms for semiseparable and semiseparable plus diagonal form, methods for reducing structured rank matrices efficiently to Hessenberg form and so forth. Eigenvalue computations for the symmetric case, involving semiseparable and semiseparable plus diagonal matrices have been thoroughly explored. A first attempt for computing the eigenvalues of nonsymmetric matrices via intermediate Hessenberg-like matrices (i.e. a matrix having all subblocks in the lower triangular part of rank at most one) was restricted to the single shift strategy. Unfortunately this leads in general to the use of complex shifts switching thereby from real to complex operations. This paper will explain a general multishift implementation for Hessenberg-like matrices (semiseparable matrices are a special case and hence also admit this approach). Besides a general multishift QR-step, this will also admit restriction to real computations when computing the eigenvalues of arbitrary real matrices. Details on the implementation are provided as well as numerical experiments proving the viability of the presented approach.

  19. Step by Step: Biology Undergraduates' Problem-Solving Procedures during Multiple-Choice Assessment.

    PubMed

    Prevost, Luanna B; Lemons, Paula P

    2016-01-01

    This study uses the theoretical framework of domain-specific problem solving to explore the procedures students use to solve multiple-choice problems about biology concepts. We designed several multiple-choice problems and administered them on four exams. We trained students to produce written descriptions of how they solved the problem, and this allowed us to systematically investigate their problem-solving procedures. We identified a range of procedures and organized them as domain general, domain specific, or hybrid. We also identified domain-general and domain-specific errors made by students during problem solving. We found that students use domain-general and hybrid procedures more frequently when solving lower-order problems than higher-order problems, while they use domain-specific procedures more frequently when solving higher-order problems. Additionally, the more domain-specific procedures students used, the higher the likelihood that they would answer the problem correctly, up to five procedures. However, if students used just one domain-general procedure, they were as likely to answer the problem correctly as if they had used two to five domain-general procedures. Our findings provide a categorization scheme and framework for additional research on biology problem solving and suggest several important implications for researchers and instructors.

  20. Step by Step: Biology Undergraduates’ Problem-Solving Procedures during Multiple-Choice Assessment

    PubMed Central

    Prevost, Luanna B.; Lemons, Paula P.

    2016-01-01

    This study uses the theoretical framework of domain-specific problem solving to explore the procedures students use to solve multiple-choice problems about biology concepts. We designed several multiple-choice problems and administered them on four exams. We trained students to produce written descriptions of how they solved the problem, and this allowed us to systematically investigate their problem-solving procedures. We identified a range of procedures and organized them as domain general, domain specific, or hybrid. We also identified domain-general and domain-specific errors made by students during problem solving. We found that students use domain-general and hybrid procedures more frequently when solving lower-order problems than higher-order problems, while they use domain-specific procedures more frequently when solving higher-order problems. Additionally, the more domain-specific procedures students used, the higher the likelihood that they would answer the problem correctly, up to five procedures. However, if students used just one domain-general procedure, they were as likely to answer the problem correctly as if they had used two to five domain-general procedures. Our findings provide a categorization scheme and framework for additional research on biology problem solving and suggest several important implications for researchers and instructors. PMID:27909021

  1. Accuracy of StepWatch™ and ActiGraph Accelerometers for Measuring Steps Taken among Persons with Multiple Sclerosis

    PubMed Central

    Sandroff, Brian M.; Motl, Robert W.; Pilutti, Lara A.; Learmonth, Yvonne C.; Ensari, Ipek; Dlugonski, Deirdre; Klaren, Rachel E.; Balantrapu, Swathi; Riskin, Barry J.

    2014-01-01

    Introduction There has been increased interest in the objective monitoring of free-living walking behavior using accelerometers in clinical research involving persons with multiple sclerosis (MS). The current investigation examined and compared the accuracy of the StepWatch activity monitor and ActiGraph model GT3X+ accelerometer for capturing steps taken during various speeds of prolonged, over-ground ambulation in persons with MS who had mild, moderate, and severe disability. Methods Sixty-three persons with MS underwent a neurological examination for generation of an EDSS score and undertook two trials of walking on the GAITRite electronic walkway. Participants were fitted with accelerometers, and undertook three modified six-minute walk (6MW) tests that were interspersed with 10–15 minutes of rest. The first 6MW was undertaken at a comfortable walking speed (CWS), and the two remaining 6MW tests were undertaken above (faster walking speed; FWS) or below (slower walking speed; SWS) the participant's CWS. The actual number of steps taken was counted through direct observation using hand-tally counters. Results The StepWatch activity monitor (99.8%–99.9%) and ActiGraph model GT3X+ accelerometer (95.6%–97.4%) both demonstrated highly accurate measurement of steps taken under CWS and FWS conditions. The StepWatch had better accuracy (99.0%) than the ActiGraph (95.5%) in the overall sample under the SWS condition, and this was particularly apparent in those with severe disability (StepWatch: 95.7%; ActiGraph: 87.3%). The inaccuracy in measurement for the ActiGraph was associated with alterations of gait (e.g., slower gait velocity, shorter step length, wider base of support). Conclusions This research will help inform the choice of accelerometer to be adopted in clinical trials of MS wherein the monitoring of free-living walking behavior is of particular value. PMID:24714028

  2. Tunable Multiple-Step Plasmonic Bragg Reflectors with Graphene-Based Modulated Grating

    PubMed Central

    Qian, Qinglu; Liang, Youjian; Liang, Yue; Shao, Hongyan; Zhang, Menglai; Xiao, Ting; Wang, Jicheng

    2016-01-01

    We propose a novel plasmonic Bragg reflector (PBR) based on graphene with multiple-step silicon structure. The monolayer graphene bears locally variable optical properties by modulation of electric fields, and the periodical change of effective refractive index on graphene can be obtained by external bias voltage in the mid-infrared region. Through patterning the PBR units into multiple-step structures, we can decrease the insertion loss and suppress the rippling in transmission spectra. By introducing the defect into the multiple-step PBRs, the multiple resonance modes are formed inside the stopband by increasing the step number. This work may pave the ways for the further development of ultra-compact low-cost hyperspectral sensors in the mid-infrared region. PMID:27916930

  3. Range and Velocity Estimation of Moving Targets Using Multiple Stepped-frequency Pulse Trains

    PubMed Central

    Li, Gang; Meng, Huadong; Xia, Xiang-Gen; Peng, Ying-Ning

    2008-01-01

    Range and velocity estimation of moving targets using conventional stepped-frequency pulse radar may suffer from the range-Doppler coupling and the phase wrapping. To overcome these problems, this paper presents a new radar waveform named multiple stepped-frequency pulse trains and proposes a new algorithm. It is shown that by using multiple stepped-frequency pulse trains and the robust phase unwrapping theorem (RPUT), both of the range-Doppler coupling and the phase wrapping can be robustly resolved, and accordingly, the range and the velocity of a moving target can be accurately estimated. PMID:27879769

  4. Comparing Multiple Discrepancies Theory to Affective Models of Subjective Wellbeing

    ERIC Educational Resources Information Center

    Blore, Jed D.; Stokes, Mark A.; Mellor, David; Firth, Lucy; Cummins, Robert A.

    2011-01-01

    The Subjective Wellbeing (SWB) literature is replete with competing theories detailing the mechanisms underlying the construction and maintenance of SWB. The current study aimed to compare and contrast two of these approaches: multiple discrepancies theory (MDT) and an affective-cognitive theory of SWB. MDT posits SWB to be the result of perceived…

  5. Continuous daily assessment of multiple sclerosis disability using remote step count monitoring.

    PubMed

    Block, V J; Lizée, A; Crabtree-Hartman, E; Bevan, C J; Graves, J S; Bove, R; Green, A J; Nourbakhsh, B; Tremblay, M; Gourraud, P-A; Ng, M Y; Pletcher, M J; Olgin, J E; Marcus, G M; Allen, D D; Cree, B A C; Gelfand, J M

    2017-02-01

    Disability measures in multiple sclerosis (MS) rely heavily on ambulatory function, and current metrics fail to capture potentially important variability in walking behavior. We sought to determine whether remote step count monitoring using a consumer-friendly accelerometer (Fitbit Flex) can enhance MS disability assessment. 99 adults with relapsing or progressive MS able to walk ≥2-min were prospectively recruited. At 4 weeks, study retention was 97% and median Fitbit use was 97% of days. Substudy validation resulted in high interclass correlations between Fitbit, ActiGraph and manual step count tally during a 2-minute walk test, and between Fitbit and ActiGraph (ICC = 0.76) during 7-day home monitoring. Over 4 weeks of continuous monitoring, daily steps were lower in progressive versus relapsing MS (mean difference 2546 steps, p < 0.01). Lower average daily step count was associated with greater disability on the Expanded Disability Status Scale (EDSS) (p < 0.001). Within each EDSS category, substantial variability in step count was apparent (i.e., EDSS = 6.0 range 1097-7152). Step count demonstrated moderate-strong correlations with other walking measures. Lower average daily step count is associated with greater MS disability and captures important variability in real-world walking activity otherwise masked by standard disability scales, including the EDSS. These results support remote step count monitoring as an exploratory outcome in MS trials.

  6. Step-rate thresholds for physical activity intensity in persons with multiple sclerosis.

    PubMed

    Agiovlasitis, Stamatis; Motl, Robert W

    2014-01-01

    This study examined whether the relationship between metabolic equivalent units (METs) and step-rate is altered in persons with multiple sclerosis (MS) and developed step-rate thresholds for activity intensity for these persons. Participants were 24 persons with MS (20 women; age = 44 ± 12) and 24 healthy persons without MS (20 women; age = 41 ± 11). The MS group was divided using the 12-item MS Walking Scale (MSWS-12) into two walking impairment subgroups: (a) minimal (n = 13, MSWS-12 ≤ 12.5) and (b) mild-moderate (n = 11, MSWS-12 > 12.5). METs were measured with spirometry and step-rate with hand-tally. Step-rate, height, group, the step-rate by group interaction, and the square of step-rate significantly predicted METs. At a given height, the step-rate thresholds at 3 and 6 METs were lower for persons with minimal impairment than persons without MS and even lower for persons with mild-moderate impairment. The relationship between METs and step-rate is altered in persons with MS, lowering their step-rate thresholds for activity intensity, especially for persons with MS who have higher levels of walking impairment.

  7. Steps/day ability to predict anthropometric changes is not affected by its plausibility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We evaluated whether treating steps/day data for implausible values (<500 or >30,000) affected the ability of these data to predict intervention-induced anthropometric (waist circumference, body mass index, percent body fat, and fat mass) changes. Data were from 269 African American participants wh...

  8. Steady state multiplicity of two-step biological conversion systems with general kinetics.

    PubMed

    Volcke, E I P; Sbarciog, M; Noldus, E J L; De Baets, B; Loccufier, M

    2010-12-01

    This study analyses the steady state behaviour of biological conversion systems with general kinetics, in which two consecutive reactions are carried out by two groups of micro-organisms. The model considered is a realistic description of wastewater treatment processes. A step-wise procedure is followed to reveal the mechanisms affecting the occurrence of steady states in terms of the process input variables. It is clearly demonstrated how taking into account inhibition effects by simply including additional inhibition terms to the kinetic expressions, a common practice, influences the model's long term behaviour. The overall steady state behaviour of the model has been summarized in easy-to-interpret operating diagrams, depicting the occurrence of steady states in terms of the reactor dilution rate and the influent substrate concentration, with well-defined boundaries between distinct operating regions. This knowledge is crucial for modelers as steady state multiplicity--in the sense that more than one steady state can be reached depending on the initial conditions--may remain undetected during simulation. The obtained results may also serve for experimental design and for model validation based on experimental findings.

  9. Copackaging of Multiple Adeno-Associated Viral Vectors in a Single Production Step

    PubMed Central

    Doerfler, Phillip A.; Byrne, Barry J.

    2014-01-01

    Abstract Limiting factors in large preclinical and clinical studies utilizing adeno-associated virus (AAV) for gene therapy are focused on the restrictive packaging capacity, the overall yields, and the versatility of the production methods for single AAV vector production. Furthermore, applications where multiple vectors are needed to provide long expression cassettes, whether because of long cDNA sequences or the need of different regulatory elements, require that each vector be packaged and characterized separately, directly affecting labor and cost associated with such manufacturing strategies. To overcome these limitations, we propose a novel method of vector production that allows for the packaging of multiple expression cassettes in a single transfection step. Here we combined two expression cassettes in predetermined ratios before transfection and empirically demonstrate that the output vector recapitulates the predicted ratios. Titration by quantitative polymerase chain reaction of AAV vector genome copies using shared or unique genetic elements allowed for delineation of the individual vector contribution to the total preparation that showed the predicted differential packaging outcomes. By copackaging green fluorescent protein (GFP) and mCherry constructs, we demonstrate that both vector genome and infectious titers reiterated the ratios utilized to produce the constructs by transfection. Copackaged therapeutic constructs that only differ in transcriptional elements produced a heterogeneous vector population of both constructs in the predefined ratios. This study shows feasibility and reproducibility of a method that allows for two constructs, differing in either transgene or transcription elements, to be efficiently copackaged and characterized simultaneously, reducing cost of manufacturing and release testing. PMID:25143183

  10. Clinical Importance of Steps Taken per Day among Persons with Multiple Sclerosis

    PubMed Central

    Motl, Robert W.; Pilutti, Lara A.; Learmonth, Yvonne C.; Goldman, Myla D.; Brown, Ted

    2013-01-01

    Background The number of steps taken per day (steps/day) provides a reliable and valid outcome of free-living walking behavior in persons with multiple sclerosis (MS). Objective This study examined the clinical meaningfulness of steps/day using the minimal clinically important difference (MCID) value across stages representing the developing impact of MS. Methods This study was a secondary analysis of de-identified data from 15 investigations totaling 786 persons with MS and 157 healthy controls. All participants provided demographic information and wore an accelerometer or pedometer during the waking hours of a 7-day period. Those with MS further provided real-life, health, and clinical information and completed the Multiple Sclerosis Walking Scale-12 (MSWS-12) and Patient Determined Disease Steps (PDDS) scale. MCID estimates were based on regression analyses and analysis of variance for between group differences. Results The mean MCID from self-report scales that capture subtle changes in ambulation (1-point change in PDSS scores and 10-point change in MSWS-12 scores) was 779 steps/day (14% of mean score for MS sample); the mean MCID for clinical/health outcomes (MS type, duration, weight status) was 1,455 steps/day (26% of mean score for MS sample); real-life anchors (unemployment, divorce, assistive device use) resulted in a mean MCID of 2,580 steps/day (45% of mean score for MS sample); and the MCID for the cumulative impact of MS (MS vs. control) was 2,747 steps/day (48% of mean score for MS sample). Conclusion The change in motion sensor output of ∼800 steps/day appears to represent a lower-bound estimate of clinically meaningful change in free-living walking behavior in interventions of MS. PMID:24023843

  11. Step-length variability in minimally disabled women with multiple sclerosis or clinically isolated syndrome.

    PubMed

    Flegel, Melanie; Knox, Katherine; Nickel, Darren

    2012-01-01

    Gait is one of the most frequently impaired bodily functions in multiple sclerosis (MS). Determining abnormal parameters of gait in early MS could influence MS treatment and rehabilitation. The purpose of this study was to determine whether increased step-length variability could be detected in minimally disabled patients with MS or clinically isolated syndrome (CIS) using a sensored walkway gait analysis system. Nine participants with MS/CIS and nine age- and gender-matched controls were recruited for this study. MS/CIS participants underwent a neurologic examination, and all participants completed a screening interview. Each participant completed three walks at a self-selected pace and three walks at a brisk pace across the GAITRite walkway (MAP/CIR Inc, Havertown, PA). Mean values for step-length variability, step length, and velocity were calculated for each participant's self-selected and brisk trials. Independent t tests were used to compare MS/CIS participants with controls, and effect sizes were calculated. Step-length variability in the left leg at the self-selected pace was found to be greater in participants with MS/CIS than in controls, although no significant differences were found in velocity or step length. Step-length variability measurement shows promise in detecting subtle gait dysfunction. Larger, prospective studies exploring step-length variability may determine its clinical viability for detecting subtle gait dysfunction and could lead to improved prognostication of disability progression in MS.

  12. Consistency of internal fluxes in a hydrological model running at multiple time steps

    NASA Astrophysics Data System (ADS)

    Ficchi, Andrea; Perrin, Charles; Andréassian, Vazken

    2016-04-01

    Improving hydrological models remains a difficult task and many ways can be explored, among which one can find the improvement of spatial representation, the search for more robust parametrization, the better formulation of some processes or the modification of model structures by trial-and-error procedure. Several past works indicate that model parameters and structure can be dependent on the modelling time step, and there is thus some rationale in investigating how a model behaves across various modelling time steps, to find solutions for improvements. Here we analyse the impact of data time step on the consistency of the internal fluxes of a rainfall-runoff model run at various time steps, by using a large data set of 240 catchments. To this end, fine time step hydro-climatic information at sub-hourly resolution is used as input of a parsimonious rainfall-runoff model (GR) that is run at eight different model time steps (from 6 minutes to one day). The initial structure of the tested model (i.e. the baseline) corresponds to the daily model GR4J (Perrin et al., 2003), adapted to be run at variable sub-daily time steps. The modelled fluxes considered are interception, actual evapotranspiration and intercatchment groundwater flows. Observations of these fluxes are not available, but the comparison of modelled fluxes at multiple time steps gives additional information for model identification. The joint analysis of flow simulation performance and consistency of internal fluxes at different time steps provides guidance to the identification of the model components that should be improved. Our analysis indicates that the baseline model structure is to be modified at sub-daily time steps to warrant the consistency and realism of the modelled fluxes. For the baseline model improvement, particular attention is devoted to the interception model component, whose output flux showed the strongest sensitivity to modelling time step. The dependency of the optimal model

  13. Speckle evolution with multiple steps of least-squares phase removal

    SciTech Connect

    Chen Mingzhou; Dainty, Chris; Roux, Filippus S.

    2011-08-15

    We study numerically the evolution of speckle fields due to the annihilation of optical vortices after the least-squares phase has been removed. A process with multiple steps of least-squares phase removal is carried out to minimize both vortex density and scintillation index. Statistical results show that almost all the optical vortices can be removed from a speckle field, which finally decays into a quasiplane wave after such an iterative process.

  14. Multiple Time-Step Dual-Hamiltonian Hybrid Molecular Dynamics — Monte Carlo Canonical Propagation Algorithm

    PubMed Central

    Weare, Jonathan; Dinner, Aaron R.; Roux, Benoît

    2016-01-01

    A multiple time-step integrator based on a dual Hamiltonian and a hybrid method combining molecular dynamics (MD) and Monte Carlo (MC) is proposed to sample systems in the canonical ensemble. The Dual Hamiltonian Multiple Time-Step (DHMTS) algorithm is based on two similar Hamiltonians: a computationally expensive one that serves as a reference and a computationally inexpensive one to which the workload is shifted. The central assumption is that the difference between the two Hamiltonians is slowly varying. Earlier work has shown that such dual Hamiltonian multiple time-step schemes effectively precondition nonlinear differential equations for dynamics by reformulating them into a recursive root finding problem that can be solved by propagating a correction term through an internal loop, analogous to RESPA. Of special interest in the present context, a hybrid MD-MC version of the DHMTS algorithm is introduced to enforce detailed balance via a Metropolis acceptance criterion and ensure consistency with the Boltzmann distribution. The Metropolis criterion suppresses the discretization errors normally associated with the propagation according to the computationally inexpensive Hamiltonian, treating the discretization error as an external work. Illustrative tests are carried out to demonstrate the effectiveness of the method. PMID:26918826

  15. Landscape structure affects the provision of multiple ecosystem services

    NASA Astrophysics Data System (ADS)

    Lamy, T.; Liss, K. N.; Gonzalez, A.; Bennett, E. M.

    2016-12-01

    Understanding how landscape structure, the composition and configuration of land use/land cover (LULC) types, affects the relative supply of ecosystem services (ES), is critical to improving landscape management. While there is a long history of studies on landscape composition, the importance of landscape configuration has only recently become apparent. To understand the role of landscape structure in the provision of multiple ES, we must understand how ES respond to different measures of both composition and configuration of LULC. We used a multivariate framework to quantify the role of landscape configuration and composition in the provision of ten ES in 130 municipalities in an agricultural region in Southern Québec. We identified the relative influence of composition and configuration in the provision of these ES using multiple regression, and on bundles of ES using canonical redundancy analysis. We found that both configuration and composition play a role in explaining variation in the supply of ES, but the relative contribution of composition and configuration varies significantly among ES. We also identified three distinct ES bundles (sets of ES that regularly appear together on the landscape) and found that each bundle was associated with a unique area in the landscape, that mapped to a gradient in the composition and configuration of forest and agricultural LULC. These results show that the distribution of ES on the landscape depends upon both the overall composition of LULC types and their configuration on the landscape. As ES become more widely used to steer land use decision-making, quantifying the roles of configuration and composition in the provision of ES bundles can improve landscape management by helping us understand when and where the spatial pattern of land cover is important for multiple services.

  16. Hydrologic consistency analysed through modeling at multiple time steps: does hydrological model performance benefit from finer time step information?

    NASA Astrophysics Data System (ADS)

    Ficchi, Andrea; Perrin, Charles; Andréassian, Vazken

    2015-04-01

    We investigate the operational utility of fine time step hydro-climatic information using a large catchment data set. The originality of this data set lies in the availability of precipitation data from the 6-minute rain gauges of Météo-France, and in the size of the catchment set (217 French catchments in total). The rainfall-runoff model used (GR4) has been adapted to hourly and sub-hourly time steps (up to 6-minute) from the daily time step version (Perrin et al., 2003). The model is applied at different time steps ranging from 6-minute to 1 day (6-, 12-, 30-minute, 1-, 3-, 6-, 12-hour and 1 day) and the evolution of model performance for each catchment is evaluated at the daily time step by aggregation of model outputs. Three classes of behavior are found according to the trend of model performance as the time step becomes finer: (i) catchments presenting an improvement of model performance; (ii) catchments with a model performance insensitive to the time step; (iii) catchments for which the performance even deteriorates as the time step becomes finer. The reasons behind these different trends are investigated from a hydrological point of view, by relating the model sensitivity to data at finer time step to catchment descriptors. References: Perrin, C., C. Michel and V. Andréassian (2003), "Improvement of a parsimonious model for streamflow simulation", Journal of Hydrology, 279(1-4): 275-289.

  17. A multiple time stepping algorithm for efficient multiscale modeling of platelets flowing in blood plasma

    NASA Astrophysics Data System (ADS)

    Zhang, Peng; Zhang, Na; Deng, Yuefan; Bluestein, Danny

    2015-03-01

    We developed a multiple time-stepping (MTS) algorithm for multiscale modeling of the dynamics of platelets flowing in viscous blood plasma. This MTS algorithm improves considerably the computational efficiency without significant loss of accuracy. This study of the dynamic properties of flowing platelets employs a combination of the dissipative particle dynamics (DPD) and the coarse-grained molecular dynamics (CGMD) methods to describe the dynamic microstructures of deformable platelets in response to extracellular flow-induced stresses. The disparate spatial scales between the two methods are handled by a hybrid force field interface. However, the disparity in temporal scales between the DPD and CGMD that requires time stepping at microseconds and nanoseconds respectively, represents a computational challenge that may become prohibitive. Classical MTS algorithms manage to improve computing efficiency by multi-stepping within DPD or CGMD for up to one order of magnitude of scale differential. In order to handle 3-4 orders of magnitude disparity in the temporal scales between DPD and CGMD, we introduce a new MTS scheme hybridizing DPD and CGMD by utilizing four different time stepping sizes. We advance the fluid system at the largest time step, the fluid-platelet interface at a middle timestep size, and the nonbonded and bonded potentials of the platelet structural system at two smallest timestep sizes. Additionally, we introduce parameters to study the relationship of accuracy versus computational complexities. The numerical experiments demonstrated 3000x reduction in computing time over standard MTS methods for solving the multiscale model. This MTS algorithm establishes a computationally feasible approach for solving a particle-based system at multiple scales for performing efficient multiscale simulations.

  18. A Multiple Time Stepping Algorithm for Efficient Multiscale Modeling of Platelets Flowing in Blood Plasma.

    PubMed

    Zhang, Peng; Zhang, Na; Deng, Yuefan; Bluestein, Danny

    2015-03-01

    We developed a multiple time-stepping (MTS) algorithm for multiscale modeling of the dynamics of platelets flowing in viscous blood plasma. This MTS algorithm improves considerably the computational efficiency without significant loss of accuracy. This study of the dynamic properties of flowing platelets employs a combination of the dissipative particle dynamics (DPD) and the coarse-grained molecular dynamics (CGMD) methods to describe the dynamic microstructures of deformable platelets in response to extracellular flow-induced stresses. The disparate spatial scales between the two methods are handled by a hybrid force field interface. However, the disparity in temporal scales between the DPD and CGMD that requires time stepping at microseconds and nanoseconds respectively, represents a computational challenge that may become prohibitive. Classical MTS algorithms manage to improve computing efficiency by multi-stepping within DPD or CGMD for up to one order of magnitude of scale differential. In order to handle 3-4 orders of magnitude disparity in the temporal scales between DPD and CGMD, we introduce a new MTS scheme hybridizing DPD and CGMD by utilizing four different time stepping sizes. We advance the fluid system at the largest time step, the fluid-platelet interface at a middle timestep size, and the nonbonded and bonded potentials of the platelet structural system at two smallest timestep sizes. Additionally, we introduce parameters to study the relationship of accuracy versus computational complexities. The numerical experiments demonstrated 3000x reduction in computing time over standard MTS methods for solving the multiscale model. This MTS algorithm establishes a computationally feasible approach for solving a particle-based system at multiple scales for performing efficient multiscale simulations.

  19. A Multiple Time Stepping Algorithm for Efficient Multiscale Modeling of Platelets Flowing in Blood Plasma

    PubMed Central

    Zhang, Peng; Zhang, Na; Deng, Yuefan; Bluestein, Danny

    2015-01-01

    We developed a multiple time-stepping (MTS) algorithm for multiscale modeling of the dynamics of platelets flowing in viscous blood plasma. This MTS algorithm improves considerably the computational efficiency without significant loss of accuracy. This study of the dynamic properties of flowing platelets employs a combination of the dissipative particle dynamics (DPD) and the coarse-grained molecular dynamics (CGMD) methods to describe the dynamic microstructures of deformable platelets in response to extracellular flow-induced stresses. The disparate spatial scales between the two methods are handled by a hybrid force field interface. However, the disparity in temporal scales between the DPD and CGMD that requires time stepping at microseconds and nanoseconds respectively, represents a computational challenge that may become prohibitive. Classical MTS algorithms manage to improve computing efficiency by multi-stepping within DPD or CGMD for up to one order of magnitude of scale differential. In order to handle 3–4 orders of magnitude disparity in the temporal scales between DPD and CGMD, we introduce a new MTS scheme hybridizing DPD and CGMD by utilizing four different time stepping sizes. We advance the fluid system at the largest time step, the fluid-platelet interface at a middle timestep size, and the nonbonded and bonded potentials of the platelet structural system at two smallest timestep sizes. Additionally, we introduce parameters to study the relationship of accuracy versus computational complexities. The numerical experiments demonstrated 3000x reduction in computing time over standard MTS methods for solving the multiscale model. This MTS algorithm establishes a computationally feasible approach for solving a particle-based system at multiple scales for performing efficient multiscale simulations. PMID:25641983

  20. Error and timing analysis of multiple time-step integration methods for molecular dynamics

    NASA Astrophysics Data System (ADS)

    Han, Guowen; Deng, Yuefan; Glimm, James; Martyna, Glenn

    2007-02-01

    Molecular dynamics simulations of biomolecules performed using multiple time-step integration methods are hampered by resonance instabilities. We analyze the properties of a simple 1D linear system integrated with the symplectic reference system propagator MTS (r-RESPA) technique following earlier work by others. A closed form expression for the time step dependent Hamiltonian which corresponds to r-RESPA integration of the model is derived. This permits us to present an analytic formula for the dependence of the integration accuracy on short-range force cutoff range. A detailed analysis of the force decomposition for the standard Ewald summation method is then given as the Ewald method is a good candidate to achieve high scaling on modern massively parallel machines. We test the new analysis on a realistic system, a protein in water. Under Langevin dynamics with a weak friction coefficient ( ζ=1 ps) to maintain temperature control and using the SHAKE algorithm to freeze out high frequency vibrations, we show that the 5 fs resonance barrier present when all degrees of freedom are unconstrained is postponed to ≈12 fs. An iso-error boundary with respect to the short-range cutoff range and multiple time step size agrees well with the analytical results which are valid due to dominance of the high frequency modes in determining integrator accuracy. Using r-RESPA to treat the long range interactions results in a 6× increase in efficiency for the decomposition described in the text.

  1. Triaziflam and Diaminotriazine derivatives affect enantioselectively multiple herbicide target sites.

    PubMed

    Grossmann, K; Tresch, S; Plath, P

    2001-01-01

    Enantiomers of triaziflam and structurally related diaminotriazines were synthesized and their herbicidal mode of action was investigated. The compounds caused light and dark-dependent effects in multiple test systems including heterotrophic cleaver and photoautotrophic algal cell suspensions, the Hill reaction of isolated thylakoids and germinating cress seeds. Dose-response experiments revealed that the (S)-enantiomers of the compounds preferentially inhibited photosystem II electron transport (PET) and algae growth with efficacies similar to that of the herbicide atrazine. In contrast, the (R)-enantiomers of the diaminotriazines were up to 100 times more potent inhibitors of growth in cleaver cell suspensions and cress seedlings in the dark than the (S)-enantiomers. The most active compound, the (R)-enantiomer of triaziflam, inhibited shoot and root elongation of cress and maize seedlings at concentrations below 1 microM. The meristematic root tips swelled into a club shape which is typical for the action of mitotic disrupter herbicides and cellulose biosynthesis inhibitors. Microscopic examination using histochemical techniques revealed that triaziflam (R)-enantiomer blocks cell division in maize root tips 4 h after treatment. The chromosomes proceeded to a condensed state of prometaphase but were unable to progress further in the mitotic cycle. Disruption of mitosis was accompanied by a loss of spindle and phragmoplast micotubule arrays. Concomitantly, cortical microtubules decreased which could lead to isodiametric cell growth and consequently to root swelling. In addition, a decline in cellulose deposition in cell walls was found 24 h after treatment. Compared to the (R)-form, triaziflam (S)-enantiomer was clearly less active. The results suggest that triaziflam and related diaminotriazines affect enantioselectively multiple sites of action which include PET inhibitory activity, mitotic disruption by inhibiting microtubule formation and inhibition of

  2. Do centrally programmed anticipatory postural adjustments in fast stepping affect performance of an associated "touche" movement?

    PubMed

    Do, M C; Yiou, E

    1999-12-01

    Ensuring maximum speed in executing a sequence of two voluntary movements requires the second movement to be triggered only after some delay. This is due to the existence of a "relative refractory period." If the second movement is initiated during the refractory period, its speed decreases (movement time increases). In the present study we tested the existence of a refractory period during the execution of a sequence of movements involving both the upper and the lower limbs. More precisely, we examined whether the maximal speed of the touche fencing movement is affected by the anticipatory postural adjustments (APA) preceding a voluntary lunge. The touche and the lunge are similar to a pointing task and a stepping forward movement, respectively. touche consists of hitting a target with a foil at maximal velocity. The results show that (a) when the touche was initiated prior to the onset of the APA of the lunge, the maximal foil velocity remains similar to that of an isolated touche, and (b) when the touche is initiated during the development of the APA of the lunge, the maximal foil velocity is lower than in the isolated touche. Furthermore, the maximal foil velocity decreases with the temporal progression of the APA and reaches its minimal value when initiated at the time of voluntary lunge execution ('foot off'). The discussion suggests that the centrally programmed APA that are elicited in the stepping forward movement induces a refractory period which affects performance of the pointing task.

  3. Correction of Footdrop Due to Multiple Sclerosis Using the STIMuSTEP Implanted Dropped Foot Stimulator

    PubMed Central

    Wilkinson Hart, Ingrid A.; Khan, Mansoor S.; Slade-Sharman, Diana E.M.

    2016-01-01

    Background: Footdrop is a significant problem in multiple sclerosis, reducing the safety and efficiency of walking. Functional electrical stimulation (FES) can produce dorsiflexion, correcting footdrop. The purpose of this retrospective analysis of clinical study data was to compare the effect of external and implanted FES devices for the correction of footdrop. Methods: External FES was used for a minimum of 6 months before implantation. Walking performance was assessed using 10-m walking speed, 3-minute walking distance, the Physiological Cost Index, and health- and device-related quality of life and device-use questionnaires. Assessments were made before implantation and a mean (SD) of 128 (24) days after surgery, with additional walking speed measurements at 3 years. Results: Twenty-three people with multiple sclerosis received the STIMuSTEP implant. Both devices enabled statistically significant increases in walking speed and walking distance, with a strong trend toward a reduced Physiological Cost Index, indicating that walking required less effort (P = .07). Both devices improved device-related quality of life. Walking speed gain with FES was maintained at 3 years. Three implants failed after falls, and there was one case of neuropraxia. The implant was used more days per week and was quicker to put on each day than the external FES device. Conclusions: The STIMuSTEP implanted dropped foot stimulator is an effective long-term intervention for the correction of footdrop. PMID:27803639

  4. "So We Adapt Step by Step": Acculturation experiences affecting diabetes management and perceived health for Chinese American immigrants.

    PubMed

    Chun, Kevin M; Chesla, Catherine A; Kwan, Christine M L

    2011-01-01

    This study examines how acculturation affects type 2 diabetes management and perceived health for Chinese American immigrants in the U.S. Acculturation experiences or cultural adaptation experiences affecting diabetes management and health were solicited from an informant group of immigrant patients and their spouses (N = 40) during group, couple and individual interviews conducted from 2005 to 2008. A separate respondent group of immigrant patients and their spouses (N = 19) meeting inclusion criteria reviewed and confirmed themes generated by the informant group. Using interpretive phenomenology, three key themes in patients' and spouses' acculturation experiences were identified: a) utilizing health care, b) maintaining family relations and roles, and c) establishing community ties and groundedness in the U.S. Acculturation experiences reflecting these themes were broad in scope and not fully captured by current self-report and proxy acculturation measures. In the current study, shifting family roles and evaluations of diabetes care and physical environment in the U.S. significantly affected diabetes management and health, yet are overlooked in acculturation and health investigations. Furthermore, the salience and impact of specific acculturation experiences respective to diabetes management and perceived health varied across participants due to individual, family, developmental, and environmental factors. In regards to salience, maintaining filial and interdependent family relations in the U.S. was of particular concern for older participants and coping with inadequate health insurance in the U.S. was especially distressing for self-described lower-middle to middle-class participants. In terms of impact, family separation and relocating to ethnically similar neighborhoods in the U.S. differentially affected diabetes management and health due to participants' varied family relations and pre-migration family support levels and diverse cultural and linguistic

  5. One-step formation of multiple Pickering emulsions stabilized by self-assembled poly(dodecyl acrylate-co-acrylic acid) nanoparticles.

    PubMed

    Zhu, Ye; Sun, Jianhua; Yi, Chenglin; Wei, Wei; Liu, Xiaoya

    2016-09-13

    In this study, a one-step generation of stable multiple Pickering emulsions using pH-responsive polymeric nanoparticles as the only emulsifier was reported. The polymeric nanoparticles were self-assembled from an amphiphilic random copolymer poly(dodecyl acrylate-co-acrylic acid) (PDAA), and the effect of the copolymer content on the size and morphology of PDAA nanoparticles was determined by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The emulsification study of PDAA nanoparticles revealed that multiple Pickering emulsions could be generated through a one-step phase inversion process by using PDAA nanoparticles as the stabilizer. Moreover, the emulsification performance of PDAA nanoparticles at different pH values demonstrated that multiple emulsions with long-time stability could only be stabilized by PDAA nanoparticles at pH 5.5, indicating that the surface wettability of PDAA nanoparticles plays a crucial role in determining the type and stability of the prepared Pickering emulsions. Additionally, the polarity of oil does not affect the emulsification performance of PDAA nanoparticles, and a wide range of oils could be used as the oil phase to prepare multiple emulsions. These results demonstrated that multiple Pickering emulsions could be generated via the one-step emulsification process using self-assembled polymeric nanoparticles as the stabilizer, and the prepared multiple emulsions have promising potential to be applied in the cosmetic, medical, and food industries.

  6. Step wise, multiple objective calibration of a hydrologic model for a snowmelt dominated basin

    USGS Publications Warehouse

    Hay, L.E.; Leavesley, G.H.; Clark, M.P.; Markstrom, S.L.; Viger, R.J.; Umemoto, M.

    2006-01-01

    The ability to apply a hydrologic model to large numbers of basins for forecasting purposes requires a quick and effective calibration strategy. This paper presents a step wise, multiple objective, automated procedure for hydrologic model calibration. This procedure includes the sequential calibration of a model's simulation of solar radiation (SR), potential evapotranspiration (PET), water balance, and daily runoff. The procedure uses the Shuffled Complex Evolution global search algorithm to calibrate the U.S. Geological Survey's Precipitation Runoff Modeling System in the Yampa River basin of Colorado. This process assures that intermediate states of the model (SR and PET on a monthly mean basis), as well as the water balance and components of the daily hydrograph are simulated, consistently with measured values.

  7. Validation of patient determined disease steps (PDDS) scale scores in persons with multiple sclerosis

    PubMed Central

    2013-01-01

    Background The Patient Determined Disease Steps (PDDS) is a promising patient-reported outcome (PRO) of disability in multiple sclerosis (MS). To date, there is limited evidence regarding the validity of PDDS scores, despite its sound conceptual development and broad inclusion in MS research. This study examined the validity of the PDDS based on (1) the association with Expanded Disability Status Scale (EDSS) scores and (2) the pattern of associations between PDDS and EDSS scores with Functional System (FS) scores as well as ambulatory and other outcomes. Methods 96 persons with MS provided demographic/clinical information, completed the PDDS and other PROs including the Multiple Sclerosis Walking Scale-12 (MSWS-12), and underwent a neurological examination for generating FS and EDSS scores. Participants completed assessments of cognition, ambulation including the 6-minute walk (6 MW), and wore an accelerometer during waking hours over seven days. Results There was a strong correlation between EDSS and PDDS scores (ρ = .783). PDDS and EDSS scores were strongly correlated with Pyramidal (ρ = .578 &ρ = .647, respectively) and Cerebellar (ρ = .501 &ρ = .528, respectively) FS scores as well as 6 MW distance (ρ = .704 &ρ = .805, respectively), MSWS-12 scores (ρ = .801 &ρ = .729, respectively), and accelerometer steps/day (ρ = -.740 &ρ = -.717, respectively). Conclusion This study provides novel evidence supporting the PDDS as valid PRO of disability in MS. PMID:23617555

  8. One step antibody-mediated isolation and patterning of multiple cell types in microfluidic devices

    PubMed Central

    Bavli, Danny; Ezra, Elishai; Kitsberg, Daniel; Murthy, Shashi K.; Nahmias, Yaakov

    2016-01-01

    Cell-cell interactions play a key role in regeneration, differentiation, and basic tissue function taking place under physiological shear forces. However, current solutions to mimic such interactions by micro-patterning cells within microfluidic devices have low resolution, high fabrication complexity, and are limited to one or two cell types. Here, we present a microfluidic platform capable of laminar patterning of any biotin-labeled peptide using streptavidin-based surface chemistry. The design permits the generation of arbitrary cell patterns from heterogeneous mixtures in microfluidic devices. We demonstrate the robust co-patterning of α-CD24, α-ASGPR-1, and α-Tie2 antibodies for rapid isolation and co-patterning of mixtures of hepatocytes and endothelial cells. In addition to one-step isolation and patterning, our design permits step-wise patterning of multiple cell types and empty spaces to create complex cellular geometries in vitro. In conclusion, we developed a microfluidic device that permits the generation of perfusable tissue-like patterns in microfluidic devices by directly injecting complex cell mixtures such as differentiated stem cells or tissue digests with minimal sample preparation. PMID:27051469

  9. Feasibility and acceptability of a multiple risk factor intervention: The Step Up randomized pilot trial

    PubMed Central

    2011-01-01

    Background Interventions are needed which can successfully modify more than one disease risk factor at a time, but much remains to be learned about the acceptability, feasibility, and effectiveness of multiple risk factor (MRF) interventions. To address these issues and inform future intervention development, we conducted a randomized pilot trial (n = 52). This study was designed to assess the feasibility and acceptability of the Step Up program, a MRF cognitive-behavioral program designed to improve participants' mental and physical well-being by reducing depressive symptoms, promoting smoking cessation, and increasing physical activity. Methods Participants were recruited from a large health care organization and randomized to receive usual care treatment for depression, smoking, and physical activity promotion or the phone-based Step Up counseling program plus usual care. Participants were assessed at baseline, three and six months. Results The intervention was acceptable to participants and feasible to offer within a healthcare system. The pilot also offered important insights into the optimal design of a MRF program. While not powered to detect clinically significant outcomes, changes in target behaviors indicated positive trends at six month follow-up and statistically significant improvement was also observed for depression. Significantly more experimental participants reported a clinically significant improvement (50% reduction) in their baseline depression score at four months (54% vs. 26%, OR = 3.35, 95% CI [1.01- 12.10], p = 0.05) and 6 months (52% vs. 13%, OR = 7.27, 95% CI [1.85 - 37.30], p = 0.004) Conclusions Overall, results suggest the Step Up program warrants additional research, although some program enhancements may be beneficial. Key lessons learned from this research are shared to promote the understanding of others working in this field. Trial registration The trial is registered with ClinicalTrials.gov (NCT00644995). PMID:21414216

  10. BOD: a customizable bioinformatics on demand system accommodating multiple steps and parallel tasks.

    PubMed

    Qiao, Li-An; Zhu, Jing; Liu, Qingyan; Zhu, Tao; Song, Chi; Lin, Wei; Wei, Guozhu; Mu, Lisen; Tao, Jiang; Zhao, Nanming; Yang, Guangwen; Liu, Xiangjun

    2004-01-01

    The integration of bioinformatics resources worldwide is one of the major concerns of the biological community. We herein established the BOD (Bioinformatics on demand) system to use Grid computing technology to set up a virtual workbench via a web-based platform, to assist researchers performing customized comprehensive bioinformatics work. Users will be able to submit entire search queries and computation requests, e.g. from DNA assembly to gene prediction and finally protein folding, from their own office using the BOD end-user web interface. The BOD web portal parses the user's job requests into steps, each of which may contain multiple tasks in parallel. The BOD task scheduler takes an entire task, or splits it into multiple subtasks, and dispatches the task or subtasks proportionally to computation node(s) associated with the BOD portal server. A node may further split and distribute an assigned task to its sub-nodes using a similar strategy. In the end, the BOD portal server receives and collates all results and returns them to the user. BOD uses a pipeline model to describe the user's submitted data and stores the job requests/status/results in a relational database. In addition, an XML criterion is established to capture task computation program details.

  11. Multiple-Time Step Ab Initio Molecular Dynamics Based on Two-Electron Integral Screening.

    PubMed

    Fatehi, Shervin; Steele, Ryan P

    2015-03-10

    A multiple-timestep ab initio molecular dynamics scheme based on varying the two-electron integral screening method used in Hartree-Fock or density functional theory calculations is presented. Although screening is motivated by numerical considerations, it is also related to separations in the length- and timescales characterizing forces in a molecular system: Loose thresholds are sufficient to describe fast motions over short distances, while tight thresholds may be employed for larger length scales and longer times, leading to a practical acceleration of ab initio molecular dynamics simulations. Standard screening approaches can lead, however, to significant discontinuities in (and inconsistencies between) the energy and gradient when the screening threshold is loose, making them inappropriate for use in dynamics. To remedy this problem, a consistent window-screening method that smooths these discontinuities is devised. Further algorithmic improvements reuse electronic-structure information within the dynamics step and enhance efficiency relative to a naı̈ve multiple-timestepping protocol. The resulting scheme is shown to realize meaningful reductions in the cost of Hartree-Fock and B3LYP simulations of a moderately large system, the protonated sarcosine/glycine dipeptide embedded in a 19-water cluster.

  12. Loop-loop interactions govern multiple steps in indole-3-glycerol phosphate synthase catalysis.

    PubMed

    Zaccardi, Margot J; O'Rourke, Kathleen F; Yezdimer, Eric M; Loggia, Laura J; Woldt, Svenja; Boehr, David D

    2014-03-01

    Substrate binding, product release, and likely chemical catalysis in the tryptophan biosynthetic enzyme indole-3-glycerol phosphate synthase (IGPS) are dependent on the structural dynamics of the β1α1 active-site loop. Statistical coupling analysis and molecular dynamic simulations had previously indicated that covarying residues in the β1α1 and β2α2 loops, corresponding to Arg54 and Asn90, respectively, in the Sulfolobus sulfataricus enzyme (ssIGPS), are likely important for coordinating functional motions of these loops. To test this hypothesis, we characterized site mutants at these positions for changes in catalytic function, protein stability and structural dynamics for the thermophilic ssIGPS enzyme. Although there were only modest changes in the overall steady-state kinetic parameters, solvent viscosity and solvent deuterium kinetic isotope effects indicated that these amino acid substitutions change the identity of the rate-determining step across multiple temperatures. Surprisingly, the N90A substitution had a dramatic effect on the general acid/base catalysis of the dehydration step, as indicated by the loss of the descending limb in the pH rate profile, which we had previously assigned to Lys53 on the β1α1 loop. These changes in enzyme function are accompanied with a quenching of ps-ns and µs-ms timescale motions in the β1α1 loop as measured by nuclear magnetic resonance studies. Altogether, our studies provide structural, dynamic and functional rationales for the coevolution of residues on the β1α1 and β2α2 loops, and highlight the multiple roles that the β1α1 loop plays in IGPS catalysis. Thus, substitution of covarying residues in the active-site β1α1 and β2α2 loops of indole-3-glycerol phosphate synthase results in functional, structural, and dynamic changes, highlighting the multiple roles that the β1α1 loop plays in enzyme catalysis and the importance of regulating the structural dynamics of this loop through noncovalent

  13. Subtasks affecting step-length asymmetry in post-stroke hemiparetic walking.

    PubMed

    Kim, Woo-Sub

    2016-10-01

    This study was performed to investigate whether components from trunk progression (TP) and step length were related to step length asymmetry in walking in patients with hemiparesis. Gait analysis was performed for participants with hemiparesis and healthy controls. The distance between the pelvis and foot in the anterior-posterior axis was calculated at initial-contact. Step length was partitioned into anterior foot placement (AFP) and posterior foot placement (PFP). TP was partitioned into anterior trunk progression (ATP) and posterior trunk progression (PTP). The TP pattern and step length pattern were defined to represent intra-TP and intra-step spatial balance, respectively. Of 29 participants with hemiparesis, nine participants showed longer paretic step length, eight participants showed symmetric step length, and 12 participants showed shorter paretic step length. For the hemiparesis group, linear regression analysis showed that ATP asymmetry, AFP asymmetry, and TP patterns had significant predictability regarding step length asymmetry. Prolonged paretic ATP and shortened paretic AFP was the predominant pattern in the hemiparesis group, even in participants with symmetric step length. However, some participants showed same direction of ATP and AFP asymmetry. These findings indicate the following: (1) ATP asymmetries should be observed to determine individual characteristics of step length asymmetry, and (2) TP patterns can provide complementary information for non-paretic limb compensation.

  14. Formulation of an explicit-multiple-time-step time integration method for use in a global primitive equation grid model

    NASA Technical Reports Server (NTRS)

    Chao, W. C.

    1982-01-01

    With appropriate modifications, a recently proposed explicit-multiple-time-step scheme (EMTSS) is incorporated into the UCLA model. In this scheme, the linearized terms in the governing equations that generate the gravity waves are split into different vertical modes. Each mode is integrated with an optimal time step, and at periodic intervals these modes are recombined. The other terms are integrated with a time step dictated by the CFL condition for low-frequency waves. This large time step requires a special modification of the advective terms in the polar region to maintain stability. Test runs for 72 h show that EMTSS is a stable, efficient and accurate scheme.

  15. Multiple contributions to clinical presentation of flat affect in schizophrenia.

    PubMed

    Mayer, M; Alpert, M; Stastny, P; Perlick, D; Empfield, M

    1985-01-01

    Flat affect has long been recognized as a central manifestation of schizophrenia, and has more recently been appreciated as a stable and prognostically important attribute of this disorder. Yet, because it is thought to be difficult to evaluate, flat affect has been deemphasized in criterion-based diagnostic systems. Results of this study suggest that the clinical evaluation of flat affect may be contaminated by a number of behaviorally similar processes. The components we identified included right hemisphere dysfunction, retardation and extrapyramidal effects, as well as the sequelae of hospitalization. Thus, in the clinical evaluation of flat affect, a multivariate approach in which these different components are considered separately might improve the reliability of evaluation and make this important sign more useful.

  16. Step initiation interferes with working memory in nondisabled patients with the earliest multiple sclerosis-A dual-task study.

    PubMed

    Brecl Jakob, G; Remšak, T; Šega Jazbec, S; Horvat Ledinek, A; Rot, U

    2017-01-01

    Balance and cognition are affected by multiple sclerosis (MS). Cognitive-motor interference (CMI) is important for balance impairment in MS, however little is known about CMI at the earliest stages of the disease. Step initiation (SI) with anticipatory postural adjustments (APAs) has been linked to postural instability and falls in subjects with MS, therefore we aimed to assess CMI between SI and the two storage systems of working memory in patients with clinically isolated syndrome (presented as optic neuritis-ON) suggestive of MS. Twenty patients with normal/near normal visual acuity and 20 age-, weight-, height-, sex- and education-matched control subjects were included. APAs were studied using center of pressure measures in three conditions: SI alone, SI+Brooks' spatial- and SI+2-back verbal working memory task. Decrements (% change) in performance on cognitive tasks and in APA parameters were calculated. CMI was assessed combining the two decrements scores. Performance on both cognitive tasks was more affected by dual-tasking in patients compared to healthy subjects. In both groups APA parameters were not influenced by dual-tasking. CMI was higher in patients compared to healthy subjects. Our results suggest that the disease affects CMI in its earliest stages. Since both cognitive tasks were similarly affected by dual-tasking in patients and controls central executive seems to play the major role in CMI between SI and working memory. Patients prioritizing motor over cognitive task for balance maintenance suggests reduced divided attention capacity as a cause of increased CMI in the earliest MS.

  17. Multiple-Step Injection Molding for Fibrin-Based Tissue-Engineered Heart Valves

    PubMed Central

    Weber, Miriam; Gonzalez de Torre, Israel; Moreira, Ricardo; Frese, Julia; Oedekoven, Caroline; Alonso, Matilde; Rodriguez Cabello, Carlos J.

    2015-01-01

    Heart valves are elaborate and highly heterogeneous structures of the circulatory system. Despite the well accepted relationship between the structural and mechanical anisotropy and the optimal function of the valves, most approaches to create tissue-engineered heart valves (TEHVs) do not try to mimic this complexity and rely on one homogenous combination of cells and materials for the whole construct. The aim of this study was to establish an easy and versatile method to introduce spatial diversity into a heart valve fibrin scaffold. We developed a multiple-step injection molding process that enables the fabrication of TEHVs with heterogeneous composition (cell/scaffold material) of wall and leaflets without the need of gluing or suturing components together, with the leaflets firmly connected to the wall. The integrity of the valves and their functionality was proved by either opening/closing cycles in a bioreactor (proof of principle without cells) or with continuous stimulation over 2 weeks. We demonstrated the potential of the method by the two-step molding of the wall and the leaflets containing different cell lines. Immunohistology after stimulation confirmed tissue formation and demonstrated the localization of the different cell types. Furthermore, we showed the proof of principle fabrication of valves using different materials for wall (fibrin) and leaflets (hybrid gel of fibrin/elastin-like recombinamer) and with layered leaflets. The method is easy to implement, does not require special facilities, and can be reproduced in any tissue-engineering lab. While it has been demonstrated here with fibrin, it can easily be extended to other hydrogels. PMID:25654448

  18. Reliability of the Spatiotemporal Determinants of Maximal Sprint Speed in Adolescent Boys Over Single and Multiple Steps.

    PubMed

    Meyers, Robert W; Oliver, Jon L; Hughes, Michael G; Lloyd, Rhodri Steffan; Cronin, John

    2015-08-01

    The purpose of this study was to examine the reliability of the spatiotemporal determinants of maximal sprinting speed in boys over single and multiple steps. Fifty-four adolescent boys (age = 14.1 ± 0.7 years [range = 12.9-15.7 years]; height = 1.63 ± 0.09 m; body mass = 55.3 ± 13.3 kg; -0.31 ± 0.90 age from Peak Height Velocity (PHV) in years; mean ± s) volunteered to complete a 30 m sprint test on 3 occasions over a 2-week period. Speed, step length, step frequency, contact time, and flight time were assessed via an optical measurement system. Speed and step characteristics were obtained from the single-fastest step and average of the 2 and 4 fastest consecutive steps. Pairwise comparison of consecutive trials revealed the coefficient of variation (CV) for speed was greater in 4-step (CV = 7.3 & 7.5%) compared with 2-step (CV = 4.2 & 4.1%) and 1-step (CV = 4.8 & 4.6%) analysis. The CV of step length, step frequency and contact time ranged from 4.8 to 7.5% for 1-step, 3.8-5.0% for 2-step and 4.2-7.5% for 4-step analyses across all trials. An acceptable degree of reliability was achieved for the spatiotemporal and performance variables assessed in this study. Two-step analysis demonstrated the highest degree of reliability for the key spatiotemporal variables, and therefore may be the most suitable approach to monitor the spatiotemporal characteristics of maximal sprint speed in boys.

  19. How multiple mating by females affects sexual selection

    PubMed Central

    Shuster, Stephen M.; Briggs, William R.; Dennis, Patricia A.

    2013-01-01

    Multiple mating by females is widely thought to encourage post-mating sexual selection and enhance female fitness. We show that whether polyandrous mating has these effects depends on two conditions. Condition 1 is the pattern of sperm utilization by females; specifically, whether, among females, male mating number, m (i.e. the number of times a male mates with one or more females) covaries with male offspring number, o. Polyandrous mating enhances sexual selection only when males who are successful at multiple mating also sire most or all of each of their mates' offspring, i.e. only when Cov♂(m,o), is positive. Condition 2 is the pattern of female reproductive life-history; specifically, whether female mating number, m, covaries with female offspring number, o. Only semelparity does not erode sexual selection, whereas iteroparity (i.e. when Cov♀(m,o), is positive) always increases the variance in offspring numbers among females, which always decreases the intensity of sexual selection on males. To document the covariance between mating number and offspring number for each sex, it is necessary to assign progeny to all parents, as well as identify mating and non-mating individuals. To document significant fitness gains by females through iteroparity, it is necessary to determine the relative magnitudes of male as well as female contributions to the total variance in relative fitness. We show how such data can be collected, how often they are collected, and we explain the circumstances in which selection favouring multiple mating by females can be strong or weak. PMID:23339237

  20. Understanding walking activity in multiple sclerosis: step count, walking intensity and uninterrupted walking activity duration related to degree of disability.

    PubMed

    Neven, An; Vanderstraeten, Annelien; Janssens, Davy; Wets, Geert; Feys, Peter

    2016-09-01

    In multiple sclerosis (MS), physical activity (PA) is most commonly measured as number of steps, while also walking intensity and walking activity duration are keys for a healthy lifestyle. The aim of this study was to investigate (1) the number of steps persons with MS (PwMS) take; (2) the number of steps they take at low and moderate intensity; and (3) their walking activity duration for 2, 3, 6, 10, 12 and 14 uninterrupted minutes; all related to the degree of disability. 64 PwMS participated, distinguished in a mild (n = 31) and moderate MS subgroup (n = 34) based on their ambulatory dysfunction (Disease Steps). Standardized clinical tests were performed, and step data from the StepWatch Activity Monitor were collected for seven consecutive days. The results showed that (1) step count in PwMS was lower than PA recommendations, and is negatively influenced by a higher disability degree. (2) No walking was registered during 77 % of the day. PwMS are making steps for 22 % at low and only 1 % at moderate intensity. (3) Both MS subgroups rarely walk for more than six uninterrupted minutes, especially not at moderate intensity. PwMS need to be encouraged to make steps at moderate intensity, and to make steps for longer periods of time (minimal ten uninterrupted minutes).

  1. A Study on Segmented Multiple-Step Forming of Doubly Curved Thick Plate by Reconfigurable Multi-Punch Dies

    SciTech Connect

    Ko, Young Ho; Han, Myoung Soo; Han, Jong Man

    2007-05-17

    Doubly curved thick plate forming in shipbuilding industries is currently performed by a thermal forming process, called as Line Heating by using gas flame torches. Due to the empirical manual work of it, the industries are eager for an alternative way to manufacture curved thick plates for ships. It was envisaged in this study to manufacture doubly curved thick plates by the multi-punch die forming. Experiments and finite element analyses were conducted to evaluate the feasibility of the reconfigurable discrete die forming to the thick plates. Single and segmented multiple step forming procedures were considered from both forming efficiency and accuracy. Configuration of the multi-punch dies suitable for the segmented multiple step forming was also explored. As a result, Segmented multiple step forming with matched dies had a limited formability when the objective shapes become complicate, while a unmatched die configuration provided better possibility to manufacture large curved plates for ships.

  2. Multiple Weather Factors Affect Apparent Survival of European Passerine Birds

    PubMed Central

    Salewski, Volker; Hochachka, Wesley M.; Fiedler, Wolfgang

    2013-01-01

    Weather affects the demography of animals and thus climate change will cause local changes in demographic rates. In birds numerous studies have correlated demographic factors with weather but few of those examined variation in the impacts of weather in different seasons and, in the case of migrants, in different regions. Using capture-recapture models we correlated weather with apparent survival of seven passerine bird species with different migration strategies to assess the importance of selected facets of weather throughout the year on apparent survival. Contrary to our expectations weather experienced during the breeding season did not affect apparent survival of the target species. However, measures for winter severity were associated with apparent survival of a resident species, two short-distance/partial migrants and a long-distance migrant. Apparent survival of two short distance migrants as well as two long-distance migrants was further correlated with conditions experienced during the non-breeding season in Spain. Conditions in Africa had statistically significant but relatively minor effects on the apparent survival of the two long-distance migrants but also of a presumably short-distance migrant and a short-distance/partial migrant. In general several weather effects independently explained similar amounts of variation in apparent survival for the majority of species and single factors explained only relatively low amounts of temporal variation of apparent survival. Although the directions of the effects on apparent survival mostly met our expectations and there are clear predictions for effects of future climate we caution against simple extrapolations of present conditions to predict future population dynamics. Not only did weather explains limited amounts of variation in apparent survival, but future demographics will likely be affected by changing interspecific interactions, opposing effects of weather in different seasons, and the potential for

  3. Multiple weather factors affect apparent survival of European passerine birds.

    PubMed

    Salewski, Volker; Hochachka, Wesley M; Fiedler, Wolfgang

    2013-01-01

    Weather affects the demography of animals and thus climate change will cause local changes in demographic rates. In birds numerous studies have correlated demographic factors with weather but few of those examined variation in the impacts of weather in different seasons and, in the case of migrants, in different regions. Using capture-recapture models we correlated weather with apparent survival of seven passerine bird species with different migration strategies to assess the importance of selected facets of weather throughout the year on apparent survival. Contrary to our expectations weather experienced during the breeding season did not affect apparent survival of the target species. However, measures for winter severity were associated with apparent survival of a resident species, two short-distance/partial migrants and a long-distance migrant. Apparent survival of two short distance migrants as well as two long-distance migrants was further correlated with conditions experienced during the non-breeding season in Spain. Conditions in Africa had statistically significant but relatively minor effects on the apparent survival of the two long-distance migrants but also of a presumably short-distance migrant and a short-distance/partial migrant. In general several weather effects independently explained similar amounts of variation in apparent survival for the majority of species and single factors explained only relatively low amounts of temporal variation of apparent survival. Although the directions of the effects on apparent survival mostly met our expectations and there are clear predictions for effects of future climate we caution against simple extrapolations of present conditions to predict future population dynamics. Not only did weather explains limited amounts of variation in apparent survival, but future demographics will likely be affected by changing interspecific interactions, opposing effects of weather in different seasons, and the potential for

  4. Bisphenol A affects androgen receptor function via multiple mechanisms.

    PubMed

    Teng, Christina; Goodwin, Bonnie; Shockley, Keith; Xia, Menghang; Huang, Ruili; Norris, John; Merrick, B Alex; Jetten, Anton M; Austin, Christopher P; Tice, Raymond R

    2013-05-25

    Bisphenol A (BPA), is a well-known endocrine disruptor compound (EDC) that affects the normal development and function of the female and male reproductive system, however the mechanisms of action remain unclear. To investigate the molecular mechanisms of how BPA may affect ten different nuclear receptors, stable cell lines containing individual nuclear receptor ligand binding domain (LBD)-linked to the β-Gal reporter were examined by a quantitative high throughput screening (qHTS) format in the Tox21 Screening Program of the NIH. The results showed that two receptors, estrogen receptor alpha (ERα) and androgen receptor (AR), are affected by BPA in opposite direction. To confirm the observed effects of BPA on ERα and AR, we performed transient transfection experiments with full-length receptors and their corresponding response elements linked to luciferase reporters. We also included in this study two BPA analogs, bisphenol AF (BPAF) and bisphenol S (BPS). As seen in African green monkey kidney CV1 cells, the present study confirmed that BPA and BPAF act as ERα agonists (half maximal effective concentration EC50 of 10-100 nM) and as AR antagonists (half maximal inhibitory concentration IC50 of 1-2 μM). Both BPA and BPAF antagonized AR function via competitive inhibition of the action of synthetic androgen R1881. BPS with lower estrogenic activity (EC50 of 2.2 μM), did not compete with R1881 for AR binding, when tested at 30 μM. Finally, the effects of BPA were also evaluated in a nuclear translocation assays using EGPF-tagged receptors. Similar to 17β-estradiol (E2) which was used as control, BPA was able to enhance ERα nuclear foci formation but at a 100-fold higher concentration. Although BPA was able to bind AR, the nuclear translocation was reduced. Furthermore, BPA was unable to induce functional foci in the nuclei and is consistent with the transient transfection study that BPA is unable to activate AR.

  5. Assembly and benign step-by-step post-treatment of oppositely charged reduced graphene oxides for transparent conductive thin films with multiple applications.

    PubMed

    Zhu, Jiayi; He, Junhui

    2012-06-07

    We report a new approach for the fabrication of flexible and transparent conducting thin films via the layer-by-layer (LbL) assembly of oppositely charged reduced graphene oxide (RGO) and the benign step-by-step post-treatment on substrates with a low glass-transition temperature, such as glass and poly(ethylene terephthalate) (PET). The RGO dispersions and films were characterized by means of atomic force microscopy, UV-visible absorption spectrophotometery, Raman spectroscopy, transmission electron microscopy, contact angle/interface systems and a four-point probe. It was found that the graphene thin films exhibited a significant increase in electrical conductivity after the step-by-step post-treatments. The graphene thin film on the PET substrate had a good conductivity retainability after multiple cycles (30 cycles) of excessively bending (bending angle: 180°), while tin-doped indium oxide (ITO) thin films on PET showed a significant decrease in electrical conductivity. In addition, the graphene thin film had a smooth surface with tunable wettability.

  6. Multiple dietary supplements do not affect metabolic and cardiovascular health

    PubMed Central

    Holloszy, John O.; Fontana, Luigi

    2014-01-01

    Dietary supplements are widely used for health purposes. However, little is known about the metabolic and cardiovascular effects of combinations of popular over-the-counter supplements, each of which has been shown to have anti-oxidant, anti-inflammatory and pro-longevity properties in cell culture or animal studies. This study was a 6-month randomized, single-blind controlled trial, in which 56 non-obese (BMI 21.0-29.9 kg/m2) men and women, aged 38 to 55 yr, were assigned to a dietary supplement (SUP) group or control (CON) group, with a 6-month follow-up. The SUP group took 10 dietary supplements each day (100 mg of resveratrol, a complex of 800 mg each of green, black, and white tea extract, 250 mg of pomegranate extract, 650 mg of quercetin, 500 mg of acetyl-l-carnitine, 600 mg of lipoic acid, 900 mg of curcumin, 1 g of sesamin, 1.7 g of cinnamon bark extract, and 1.0 g fish oil). Both the SUP and CON groups took a daily multivitamin/mineral supplement. The main outcome measures were arterial stiffness, endothelial function, biomarkers of inflammation and oxidative stress, and cardiometabolic risk factors. Twenty-four weeks of daily supplementation with 10 dietary supplements did not affect arterial stiffness or endothelial function in nonobese individuals. These compounds also did not alter body fat measured by DEXA, blood pressure, plasma lipids, glucose, insulin, IGF-1, and markers of inflammation and oxidative stress. In summary, supplementation with a combination of popular dietary supplements has no cardiovascular or metabolic effects in non-obese relatively healthy individuals. PMID:24659610

  7. Intronless mRNA transport elements may affect multiple steps of pre-mRNA processing.

    PubMed Central

    Huang, Y; Wimler, K M; Carmichael, G G

    1999-01-01

    We have reported recently that a small element within the mouse histone H2a-coding region permits efficient cytoplasmic accumulation of intronless beta-globin cDNA transcripts. This sequence lowers the levels of spliced products from intron-containing constructs and can functionally replace Rev and the Rev-responsive element (RRE) in the nuclear export of unspliced HIV-1-related mRNAs. In work reported here, we further investigate the molecular mechanisms by which this element might work. We demonstrate here through both in vivo and in vitro assays that, in addition to promoting mRNA nuclear export, this element acts as a polyadenylation enhancer and as a potent inhibitor of splicing. Surprisingly, two other described intronless mRNA transport elements (from the herpes simplex virus thymidine kinase gene and hepatitis B virus) appear to function in a similar manner. These findings prompt us to suggest that a general feature of intronless mRNA transport elements might be a collection of phenotypes, including the inhibition of splicing and the enhancement of both polyadenylation and mRNA export. PMID:10075934

  8. Supporting Affect Regulation in Children with Multiple Disabilities during Psychotherapy: A Multiple Case Design Study of Therapeutic Attachment

    ERIC Educational Resources Information Center

    Schuengel, C.; Sterkenburg, P. S.; Jeczynski, P.; Janssen, C. G. C.; Jongbloed, G.

    2009-01-01

    In a controlled multiple case design study, the development of a therapeutic relationship and its role in affect regulation were studied in 6 children with visual disabilities, severe intellectual disabilities, severe challenging behavior, and prolonged social deprivation. In the 1st phase, children had sessions with an experimental therapist…

  9. Investigating the Variation of Volatile Compound Composition in Maotai-Flavoured Liquor During Its Multiple Fermentation Steps Using Statistical Methods

    PubMed Central

    Wu, Zheng-Yun; Lei, Xue-Jun; Zhu, De-Wen

    2016-01-01

    Summary The use of multiple fermentations is one of the most specific characteristics of Maotai--flavoured liquor production. In this research, the variation of volatile composition of Maotai-flavoured liquor during its multiple fermentations is investigated using statistical approaches. Cluster analysis shows that the obtained samples are grouped mainly according to the fermentation steps rather than the distillery they originate from, and the samples from the first two fermentation steps show the greatest difference, suggesting that multiple fermentation and distillation steps result in the end in similar volatile composition of the liquor. Back-propagation neural network (BNN) models were developed that satisfactorily predict the number of fermentation steps and the organoleptic evaluation scores of liquor samples from their volatile compositions. Mean impact value (MIV) analysis shows that ethyl lactate, furfural and some high-boiling-point acids play important roles, while pyrazine contributes much less to the improvement of the flavour and taste of Maotai-flavoured liquor during its production. This study contributes to further understanding of the mechanisms of Maotai-flavoured liquor production. PMID:27904415

  10. 78 FR 7659 - Revised Medical Criteria for Evaluating Congenital Disorders That Affect Multiple Body Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-04

    ... impairments that affect multiple body systems in adults and children under titles II and XVI of the Social... eligibility or filing for benefits, call our national toll-free number, 1-800-772-1213, or TTY 1-800-325-0778... the appropriate affected body system(s), such as musculoskeletal, special senses and...

  11. Multiple step-variable pathway hypothesis: a reason why predictions fail in atherosclerosis.

    PubMed

    Ferns, Gordon A A

    2008-12-01

    Cardiovascular risk factors are individually only modest predictors of events, and whilst more sophisticated algorithms appear to improve their prediction, a significant proportion of the population is miscategorised and therefore managed inappropriately. It is proposed that atherogenesis is a multi-step process, and that the critical transitions between steps requires 'bundles' of risk factors that may differ for each step. These bundles may not always contain a classical risk factor and may differ between individuals. This hypothesis would predict that the impact of specific risk factors is non-uniform during atherogenesis and therefore the efficacy of interventions will vary with stage. New therapeutic opportunities exist if the factors that promote progression between particular stages could be identified and targeted. The staging of disease using modalities such as imaging and functional assessment may be necessary to deliver the most effective treatment. Finally, risk assessment will invariably be inaccurate, even using complex algorithms.

  12. The US Network of Pediatric Multiple Sclerosis Centers: Development, Progress, and Next Steps.

    PubMed

    Casper, T Charles; Rose, John W; Roalstad, Shelly; Waubant, Emmanuelle; Aaen, Gregory; Belman, Anita; Chitnis, Tanuja; Gorman, Mark; Krupp, Lauren; Lotze, Timothy E; Ness, Jayne; Patterson, Marc; Rodriguez, Moses; Weinstock-Guttman, Bianca; Browning, Brittan; Graves, Jennifer; Tillema, Jan-Mendelt; Benson, Leslie; Harris, Yolanda

    2015-09-01

    Multiple sclerosis and other demyelinating diseases in the pediatric population have received an increasing level of attention by clinicians and researchers. The low incidence of these diseases in children creates a need for the involvement of multiple clinical centers in research efforts. The Network of Pediatric Multiple Sclerosis Centers was created initially in 2006 to improve the diagnosis and care of children with demyelinating diseases. In 2010, the Network shifted its focus to multicenter research while continuing to advance the care of patients. The Network has obtained support from the National Multiple Sclerosis Society, the Guthy-Jackson Charitable Foundation, and the National Institutes of Health. The Network will continue to serve as a platform for conducting impactful research in pediatric demyelinating diseases of the central nervous system. This article provides a description of the history and development, organization, mission, research priorities, current studies, and future plans of the Network.

  13. Multiple time step molecular dynamics in the optimized isokinetic ensemble steered with the molecular theory of solvation: Accelerating with advanced extrapolation of effective solvation forces

    SciTech Connect

    Omelyan, Igor E-mail: omelyan@icmp.lviv.ua; Kovalenko, Andriy

    2013-12-28

    We develop efficient handling of solvation forces in the multiscale method of multiple time step molecular dynamics (MTS-MD) of a biomolecule steered by the solvation free energy (effective solvation forces) obtained from the 3D-RISM-KH molecular theory of solvation (three-dimensional reference interaction site model complemented with the Kovalenko-Hirata closure approximation). To reduce the computational expenses, we calculate the effective solvation forces acting on the biomolecule by using advanced solvation force extrapolation (ASFE) at inner time steps while converging the 3D-RISM-KH integral equations only at large outer time steps. The idea of ASFE consists in developing a discrete non-Eckart rotational transformation of atomic coordinates that minimizes the distances between the atomic positions of the biomolecule at different time moments. The effective solvation forces for the biomolecule in a current conformation at an inner time step are then extrapolated in the transformed subspace of those at outer time steps by using a modified least square fit approach applied to a relatively small number of the best force-coordinate pairs. The latter are selected from an extended set collecting the effective solvation forces obtained from 3D-RISM-KH at outer time steps over a broad time interval. The MTS-MD integration with effective solvation forces obtained by converging 3D-RISM-KH at outer time steps and applying ASFE at inner time steps is stabilized by employing the optimized isokinetic Nosé-Hoover chain (OIN) ensemble. Compared to the previous extrapolation schemes used in combination with the Langevin thermostat, the ASFE approach substantially improves the accuracy of evaluation of effective solvation forces and in combination with the OIN thermostat enables a dramatic increase of outer time steps. We demonstrate on a fully flexible model of alanine dipeptide in aqueous solution that the MTS-MD/OIN/ASFE/3D-RISM-KH multiscale method of molecular dynamics

  14. Multiple time step molecular dynamics in the optimized isokinetic ensemble steered with the molecular theory of solvation: Accelerating with advanced extrapolation of effective solvation forces

    NASA Astrophysics Data System (ADS)

    Omelyan, Igor; Kovalenko, Andriy

    2013-12-01

    We develop efficient handling of solvation forces in the multiscale method of multiple time step molecular dynamics (MTS-MD) of a biomolecule steered by the solvation free energy (effective solvation forces) obtained from the 3D-RISM-KH molecular theory of solvation (three-dimensional reference interaction site model complemented with the Kovalenko-Hirata closure approximation). To reduce the computational expenses, we calculate the effective solvation forces acting on the biomolecule by using advanced solvation force extrapolation (ASFE) at inner time steps while converging the 3D-RISM-KH integral equations only at large outer time steps. The idea of ASFE consists in developing a discrete non-Eckart rotational transformation of atomic coordinates that minimizes the distances between the atomic positions of the biomolecule at different time moments. The effective solvation forces for the biomolecule in a current conformation at an inner time step are then extrapolated in the transformed subspace of those at outer time steps by using a modified least square fit approach applied to a relatively small number of the best force-coordinate pairs. The latter are selected from an extended set collecting the effective solvation forces obtained from 3D-RISM-KH at outer time steps over a broad time interval. The MTS-MD integration with effective solvation forces obtained by converging 3D-RISM-KH at outer time steps and applying ASFE at inner time steps is stabilized by employing the optimized isokinetic Nosé-Hoover chain (OIN) ensemble. Compared to the previous extrapolation schemes used in combination with the Langevin thermostat, the ASFE approach substantially improves the accuracy of evaluation of effective solvation forces and in combination with the OIN thermostat enables a dramatic increase of outer time steps. We demonstrate on a fully flexible model of alanine dipeptide in aqueous solution that the MTS-MD/OIN/ASFE/3D-RISM-KH multiscale method of molecular dynamics

  15. The GOL-NB program: further steps in multiple-mirror confinement research

    NASA Astrophysics Data System (ADS)

    Postupaev, V. V.; Batkin, V. I.; Beklemishev, A. D.; Burdakov, A. V.; Burmasov, V. S.; Chernoshtanov, I. S.; Gorbovsky, A. I.; Ivanov, I. A.; Kuklin, K. N.; Mekler, K. I.; Rovenskikh, A. F.; Sidorov, E. N.; Yurov, D. V.

    2017-03-01

    Physical and technical details of the GOL-NB project are presented. GOL-NB is a medium-scale multiple-mirror trap that is under development in the Budker Institute, Novosibirsk, Russia. This device will be created in several years as a deep conversion of the existing GOL-3 facility. It will consist of a central trap with two 0.75 MW neutral beams, two multiple-mirror solenoids, two expander tanks and a plasma gun that creates the start plasma. The central trap with the neutral beam injection-heated plasma is a compact gas-dynamic system. The multiple-mirror sections should decrease the power and particle losses along the magnetic field. The confinement improvement factor depends on plasma parameters and on the magnetic configuration in the multiple mirrors. The main physical task of GOL-NB is direct demonstration of the performance of multiple-mirror sections that will change equilibrium plasma parameters in the central trap. In this paper we discuss results of the scenario modeling and progress in the hardware.

  16. Evidence that a ‘dynamic knockout’ in Escherichia coli dihydrofolate reductase does not affect the chemical step of catalysis

    NASA Astrophysics Data System (ADS)

    Loveridge, E. Joel; Behiry, Enas M.; Guo, Jiannan; Allemann, Rudolf K.

    2012-04-01

    The question of whether protein motions play a role in the chemical step of enzymatic catalysis has generated much controversy in recent years. Debate has recently reignited over possible dynamic contributions to catalysis in dihydrofolate reductase, following conflicting conclusions from studies of the N23PP/S148A variant of the Escherichia coli enzyme. By investigating the temperature dependence of kinetic isotope effects, we present evidence that the reduction in the hydride transfer rate constants in this variant is not a direct result of impairment of conformational fluctuations. Instead, the conformational state of the enzyme immediately before hydride transfer, which determines the electrostatic environment of the active site, affects the rate constant for the reaction. Although protein motions are clearly important for binding and release of substrates and products, there appears to be no detectable dynamic coupling of protein motions to the hydride transfer step itself.

  17. Ultrastructural examination of one-step self-etch adhesive bonded primary sound and caries-affected dentin

    PubMed Central

    HOSOYA, YUMIKO; TAY, FRANKLIN R.; GARCÍA-GODOY, FRANKLIN; PASHLEY, DAVID H.

    2013-01-01

    Purpose This study examined the ultrastructure and silver nanoleakage of the resin-dentin interfaces in sound and caries-affected primary tooth dentin bonded with a 4-META one-step self-etch adhesive. Materials and Methods Each of five sound and carious primary molars was bonded with Hybrid Bond. Resin-dentin interfaces were observed with TEM micrographs obtained from silver-impregnated, unstained and undemineralized sections of bonded sound and caries-affected primary dentin, and stained and demineralized sections of bonded sound primary dentin with silver impregnation. Results For sound dentin, silver nanoleakage was observed extensively in the patent dentinal tubules, within the dentin beneath the hybrid layer, within the hybrid layer in some specimens, and as water trees that partially protruded into the overlying adhesive layer. The hybrid layer was about 1 μm thick. Smear plugs in the dentinal tubules and smear on the ground dentin protruded in the hybrid layer. Remnants of demineralized smear were observed overlying adhesive layer. For caries-affected dentin, the hybrid layer was obscure. Dentinal tubules were occluded with mineral deposits. There were no water trees or nanoleakage in the adhesive layer or hybrid layer. However, smear remnants were observed in adhesive layer and heavily silver deposits were observed in the highly porous underlying caries-affected dentin. PMID:19146129

  18. Nanoscale physicochemical properties of chain- and step-growth polymerized PEG hydrogels affect cell-material interactions.

    PubMed

    Vats, Kanika; Marsh, Graham; Harding, Kristen; Zampetakis, Ioannis; Waugh, Richard E; Benoit, Danielle S W

    2017-04-01

    Poly(ethylene glycol) (PEG) hydrogels provide a versatile platform to develop cell instructive materials through incorporation of a variety of cell adhesive ligands and degradable chemistries. Synthesis of PEG gels can be accomplished via two mechanisms: chain and step growth polymerizations. The mechanism dramatically impacts hydrogel nanostructure, whereby chain polymerized hydrogels are highly heterogeneous and step growth networks exhibit more uniform structures. Underpinning these alterations in nanostructure of chain polymerized hydrogels are densely-packed hydrophobic poly(methyl methacrylate) or poly(acrylate) kinetic chains between hydrophilic PEG crosslinkers. As cell-material interactions, such as those mediated by integrins, occur at the nanoscale and affect cell behavior, it is important to understand how different modes of polymerization translate into nanoscale mechanical and hydrophobic heterogeneities of hydrogels. Therefore, chain- and step-growth polymerized PEG hydrogels with macroscopically similar macromers and compliance (for example, methacrylate-functionalized PEG (PEGDM), MW  = 10 kDa and norbornene-functionalized 4-arm PEG (PEGnorb), MW  = 10 kDa) were used to examine potential nanoscale differences in hydrogel mechanics and hydrophobicity using atomic force microscopy (AFM). It was found that chain-growth polymerized network yielded greater heterogeneities in both stiffness and hydrophobicity as compared to step-growth polymerized networks. These nanoscale heterogeneities impact cell-material interactions, particularly human mesenchymal stem cell (hMSC) adhesion and spreading, which has implications in use of these hydrogels for tissue engineering applications. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1112-1122, 2017.

  19. Simultaneous determination of multiple (fluoro)quinolone antibiotics in food samples by a one-step fluorescence polarization immunoassay.

    PubMed

    Mi, Tiejun; Wang, Zhanhui; Eremin, Sergei A; Shen, Jianzhong; Zhang, Suxia

    2013-10-02

    This paper describes a rapid one-step fluorescence polarization immunoassay (FPIA) for the simultaneous determination of multiple (fluoro)quinolone antibiotics (FQs) in food samples. Several fluorescent tracers were synthesized and evaluated in the FPIA method based on a broad-specificity of monoclonal antibodies toward FQs. The heterogeneous tracer, SAR-5-FAM, was considered as the optimal choice to prepare the immunocomplex single reagent, which allows a rapid and sensitive displacement reaction by addition of analytes. Optimized single-reagent FPIA exhibited broad cross-reactivities in the range of 7.8-172.2% with 16 FQs tested and was capable of determining most FQs at the level of maximum residue limits. Recoveries for spiked milk and chicken muscle samples were from 77.8 to 116%, with relative standard deviation lower than 17.4%. Therefore, this method could be applicable in routine screening analysis of multiple FQ residues in food samples.

  20. Linking and Psychological Functioning in a Chinese Sample: The Multiple Mediation of Response to Positive Affect

    ERIC Educational Resources Information Center

    Yang, Hongfei; Li, Juan

    2016-01-01

    The present study examined the associations between linking, response to positive affect, and psychological functioning in Chinese college students. The results of conducting multiple mediation analyses indicated that emotion- and self-focused positive rumination mediated the relationship between linking and psychological functioning, whereas…

  1. Supporting affect regulation in children with multiple disabilities during psychotherapy: a multiple case design study of therapeutic attachment.

    PubMed

    Schuengel, C; Sterkenburg, P S; Jeczynski, P; Janssen, C G C; Jongbloed, G

    2009-04-01

    In a controlled multiple case design study, the development of a therapeutic relationship and its role in affect regulation were studied in 6 children with visual disabilities, severe intellectual disabilities, severe challenging behavior, and prolonged social deprivation. In the 1st phase, children had sessions with an experimental therapist stimulating therapeutic attachment, alternating with a control therapist providing positive personal attention only. In the 2nd phase, both therapists applied behavior therapy. Clients sought more proximity to the experimental therapist compared with the control therapist. Psychophysiological arousal (respiratory sinus arrhythmia and pre-ejection period) was lower when the experimental therapist applied behavior modification than when the control therapist did. Despite prolonged social deprivation, the attachment behavioral system appeared responsive to stimulation. The effects on affect regulation may explain the synergy between psychotherapy based on interpersonal and behavior modification approaches.

  2. Rapid one-step inactivation of single or multiple genes in Escherichia coli.

    PubMed

    Song, Chan Woo; Lee, Sang Yup

    2013-07-01

    Gene knockout experiments are frequently performed for both fundamental and applied biological research. We developed an integration helper plasmid-based knockout system for more efficient and rapid engineering of Escherichia coli. The integration helper plasmid, pCW611, contains two recombinases that are expressed in the reverse direction by two independent inducible systems. One is Red recombinase under the control of the arabinose-inducible system to induce a recombination event by using the linear gene knockout DNA fragment, while the other is Cre recombinase, which is controlled by the isopropyl β-D-1-thiogalactopyranoside-inducible system to obtain markerless mutant strains. The time and effort required can be reduced with this system because iterative transformation and curing steps are not required. We could delete one target gene in three days by using pCW611. To verify the usefulness of this system, deletion experiments were performed to knock out four target genes individually (adhE, sfcA, frdABCD, and ackA) and two genes simultaneously for two cases (adhE-aspA and sfcA-aspA). Also, sequential deletion of four target genes (fumB, iclR, fumA, and fumC) was successfully performed to make a fumaric acid producing strain. This successfully developed and validated rapid and efficient gene manipulation system should be useful for the metabolic engineering of E. coli.

  3. GreenCube: A Student Multiple Small Payload Project: A First Step

    NASA Astrophysics Data System (ADS)

    Bracikowski, P. J.; Fagrelius, P. A.; Siddiqui, M. U.; Lynch, K. A.; Millan, R. M.

    2008-12-01

    Based on the CubeSat Project, which is a small satellite prototype established by CalPoly and Stanford Universities, Dartmouth College undergraduates have built a prototype 10cm x 10 cm x 30cm payload, dubbed GreenCube. The prototype consists of a number of subsystems: a data acquisition and analysis computer, power source and regulatory circuits, telemetry, GPS, and instruments. The on-board instruments are a magnetometer and 6 thermocouples that are stand-ins for future devices. The telemetry system alone, acting as a simple beacon, was flown on a 30km bursting-balloon in early June 2008. The beacon signal, which we successfully monitored for the entire flight, transmitted temperature readings from a built-in temperature sensor. We also successfully recovered the payload after a parachute return. The June flight served as a trial run of our balloon team and payload systems, and future flights are planned to test the full payload. Our long-term science goals take two forms. The GreenCube prototype will be applicable as an instrument platform for auroral sounding rockets and for future CubeSat missions. We are interested in a sounding rocket involving the release of approximately 8 small sub-payloads from a main payload to be flown from Poker Flat Alaska. Each sub-payload would be untethered and independent from the main payload and communicate independently to the ground station. This type of mission would investigate the k-spectrum of density irregularities in the auroral ionosphere, for which we will substitute plasma density probes for the thermocouples. Before flying the small payloads on a sounding rocket, though, our next step will be to launch the entire GreenCube payload on a balloon and then from a student test rocket within the next two years.

  4. A versatile bacterial expression vector designed for single-step cloning of multiple DNA fragments using homologous recombination.

    PubMed

    Holmberg, Mats A; Gowda, Naveen Kumar Chandappa; Andréasson, Claes

    2014-06-01

    Production of recombinant proteins is the starting point for biochemical and biophysical analyses and requires methodology to efficiently proceed from gene sequence to purified protein. While optimized strategies for the efficient cloning of single-gene fragments for bacterial expression is available, efficient multiple DNA fragment cloning still presents a challenge. To facilitate this step, we have developed an efficient cloning strategy based on yeast homologous recombination cloning (YHRC) into the new pET-based bacterial expression vector pSUMO-YHRC. The vector supports cloning for untagged expression as well as fusions to His6-SUMO or His6 tags. We demonstrate that YHRC from single PCR products of 6 independent genes into the vector results in virtually no background. Importantly, in a quantitative assay for functional expression we find that single-step YHRC of 7 DNA fragments can be performed with very high cloning efficiencies. The method and reagents described in this paper significantly simplifies the construction of expression plasmids from multiple DNA fragments, including complex gene fusions, chimeric genes and polycistronic constructs.

  5. Ethacrynic acid inhibits multiple steps in the NF-kappaB signaling pathway.

    PubMed

    Han, Yusheng; Englert, Joshua A; Delude, Russell L; Fink, Mitchell P

    2005-01-01

    Ethacrynic acid has been used as a safe and effective diuretic for more than 30 years. In this study, we tested the hypothesis that ethacrynic acid is also an anti-inflammatory agent that inhibits signaling by the proinflammatory transcription factor NF-kappaB. We showed that ethacrynic acid inhibited luciferase expression in lipopolysaccharide-stimulated macrophage-like RAW 264.7 cells transfected with an NF-kappaB-dependent luciferase reporter vector and also inhibited NF-kappaB DNA binding in lipopolysaccharide-stimulated RAW 264.7 cells (electrophoretic mobility shift assay). Ethacrynic acid inhibited degradation of IkappaBalpha and IkappaBbeta in lipopolysaccharide-stimulated RAW 264.7 cells. Ethacrynic acid impaired DNA binding of wild-type p65 subunits of NF-kappaB in cells. However, DNA binding of a Cys--> Ser p65 mutant was not inhibited by ethacrynic acid, suggesting that ethacrynic acid inhibits DNA binding by alkylating p65 at Cys. In a cell-free system, binding of p50 homodimers to an NF-kappaB consensus sequence was inhibited by ethacrynic acid at concentrations from 10 to 100 microM, indicating that ethacrynic acid probably also covalently modifies the p50 subunit. These data indicate that ethacrynic acid inhibits activation of the NF-kappaB pathway at multiple points and suggest that this well-studied drug warrants further investigation as a potential therapeutic for various conditions that are associated with excessive inflammation.

  6. Acceleration of Ab Initio QM/MM Calculations under Periodic Boundary Conditions by Multiscale and Multiple Time Step Approaches.

    PubMed

    Nam, Kwangho

    2014-10-14

    Development of multiscale ab initio quantum mechanical and molecular mechanical (AI-QM/MM) method for periodic boundary molecular dynamics (MD) simulations and their acceleration by multiple time step approach are described. The developed method achieves accuracy and efficiency by integrating the AI-QM/MM level of theory and the previously developed semiempirical (SE) QM/MM-Ewald sum method [J. Chem. Theory Comput. 2005, 1, 2] extended to the smooth particle-mesh Ewald (PME) summation method. In the developed methods, the total energy of the simulated system is evaluated at the SE-QM/MM-PME level of theory to include long-range QM/MM electrostatic interactions, which is then corrected on the fly using the AI-QM/MM level of theory within the real space cutoff. The resulting energy expression enables decomposition of total forces applied to each atom into forces determined at the low-level SE-QM/MM method and correction forces at the AI-QM/MM level, to integrate the system using the reversible reference system propagator algorithm. The resulting method achieves a substantial speed-up of the entire calculation by minimizing the number of time-consuming energy and gradient evaluations at the AI-QM/MM level. Test calculations show that the developed multiple time step AI-QM/MM method yields MD trajectories and potential of mean force profiles comparable to single time step QM/MM results. The developed method, together with message passing interface (MPI) parallelization, accelerates the present AI-QM/MM MD simulations about 30-fold relative to the speed of single-core AI-QM/MM simulations for the molecular systems tested in the present work, making the method less than one order slower than the SE-QM/MM methods under periodic boundary conditions.

  7. Technological steps and yeast biomass as factors affecting the lipid content of beer during the brewing process.

    PubMed

    Bravi, Elisabetta; Perretti, Giuseppe; Buzzini, Pietro; Della Sera, Rolando; Fantozzi, Paolo

    2009-07-22

    Knowledge of lipid content and composition in the brewing process enables the quality control of the final product. Lipids have a beneficial effect on yeast growth during fermentation as well as deleterious effects on end-product quality. The lipid content of a beer affects its ability to form a stable head of foam and plays an important role in beer staling. Lipid oxidation during wort production is of great interest because of its effect on beer quality: both lipids and their oxidation products are known to have adverse effects on beer flavor, whereas interactions between lipids and protein films stabilizing the gas bubbles are thought to cause the collapse of foam. In this background, the aim of this research was the characterization of the lipid content during a brewing process for evaluating the influence of both technological steps and yeast biomass in the lipid composition of beer. Lipid contents and their fatty acid profile were evaluated in brewing raw materials, wort, and beer. A high-resolution gas chromatography-flame ionization detector (HRGC-FID) system was used for fatty acid determination in lipid extracts. The results of the present study highlighted that the main technological steps influencing the lipid content in brewing byproduct and beer were clarification in a whirlpool and filtration. Moreover, the presence of metabolically active yeast cells (used as starter culture) were found to have a great influence on the fatty acids composition of lipids.

  8. [Integrated risk evaluation of multiple disasters affecting longyan yield in Fujian Province, East China].

    PubMed

    Chen, Jia-Jin; Wang, Jia-Yi; Li, Li-Chun; Lin, Jing; Yang, Kai; Ma, Zhi-Guo; Xu, Zong-Huan

    2012-03-01

    In this study, an index system for the integrated risk evaluation of multiple disasters on the Longyan production in Fujian Province was constructed, based on the analysis of the major environmental factors affecting the Longyan growth and yield, and from the viewpoints of potential hazard of disaster-causing factors, vulnerability of hazard-affected body, and disaster prevention and mitigation capability of Longyan growth regions in the Province. In addition, an integrated evaluation model of multiple disasters was established to evaluate the risks of the major agro-meteorological disasters affecting the Longyan yield, based on the yearly meteorological data, Longyan planting area and yield, and other socio-economic data in Longyan growth region in Fujian, and by using the integral weight of risk indices determined by AHP and entropy weight coefficient methods. In the Province, the Longyan growth regions with light integrated risk of multiple disasters were distributed in the coastal counties (except Dongshan County) with low elevation south of Changle, the regions with severe and more severe integrated risk were mainly in Zhangping of Longyan, Dongshan, Pinghe, Nanjin, and Hua' an of Zhangzhou, Yongchun and Anxi of Quanzhou, north mountainous areas of Putian and Xianyou, Minqing, Minhou, Luoyuan, and mountainous areas of Fuzhou, and Fuan, Xiapu, and mountainous areas of Ninde, among which, the regions with severe integrated risk were in Dongshan, Zhangping, and other mountainous areas with high altitudes, and the regions with moderate integrated risk were distributed in the other areas of the Province.

  9. A simple test of choice stepping reaction time for assessing fall risk in people with multiple sclerosis.

    PubMed

    Tijsma, Mylou; Vister, Eva; Hoang, Phu; Lord, Stephen R

    2017-03-01

    Purpose To determine (a) the discriminant validity for established fall risk factors and (b) the predictive validity for falls of a simple test of choice stepping reaction time (CSRT) in people with multiple sclerosis (MS). Method People with MS (n = 210, 21-74y) performed the CSRT, sensorimotor, balance and neuropsychological tests in a single session. They were then followed up for falls using monthly fall diaries for 6 months. Results The CSRT test had excellent discriminant validity with respect to established fall risk factors. Frequent fallers (≥3 falls) performed significantly worse in the CSRT test than non-frequent fallers (0-2 falls). With the odds of suffering frequent falls increasing 69% with each SD increase in CSRT (OR = 1.69, 95% CI: 1.27-2.26, p = <0.001). In regression analysis, CSRT was best explained by sway, time to complete the 9-Hole Peg test, knee extension strength of the weaker leg, proprioception and the time to complete the Trails B test (multiple R(2  )= ( )0.449, p < 0.001). Conclusions A simple low tech CSRT test has excellent discriminative and predictive validity in relation to falls in people with MS. This test may prove useful in documenting longitudinal changes in fall risk in relation to MS disease progression and effects of interventions. Implications for rehabilitation Good choice stepping reaction time (CSRT) is required for maintaining balance. A simple low-tech CSRT test has excellent discriminative and predictive validity in relation to falls in people with MS. This test may prove useful documenting longitudinal changes in fall risk in relation to MS disease progression and effects of interventions.

  10. Step-response of a torsional device with multiple discontinuous non-linearities: Formulation of a vibratory experiment

    NASA Astrophysics Data System (ADS)

    Krak, Michael D.; Dreyer, Jason T.; Singh, Rajendra

    2016-03-01

    A vehicle clutch damper is intentionally designed to contain multiple discontinuous non-linearities, such as multi-staged springs, clearances, pre-loads, and multi-staged friction elements. The main purpose of this practical torsional device is to transmit a wide range of torque while isolating torsional vibration between an engine and transmission. Improved understanding of the dynamic behavior of the device could be facilitated by laboratory measurement, and thus a refined vibratory experiment is proposed. The experiment is conceptually described as a single degree of freedom non-linear torsional system that is excited by an external step torque. The single torsional inertia (consisting of a shaft and torsion arm) is coupled to ground through parallel production clutch dampers, which are characterized by quasi-static measurements provided by the manufacturer. Other experimental objectives address physical dimensions, system actuation, flexural modes, instrumentation, and signal processing issues. Typical measurements show that the step response of the device is characterized by three distinct non-linear regimes (double-sided impact, single-sided impact, and no-impact). Each regime is directly related to the non-linear features of the device and can be described by peak angular acceleration values. Predictions of a simplified single degree of freedom non-linear model verify that the experiment performs well and as designed. Accordingly, the benchmark measurements could be utilized to validate non-linear models and simulation codes, as well as characterize dynamic parameters of the device including its dissipative properties.

  11. A handheld mid-infrared methane sensor using a dual-step differential method for additive/multiplicative noise suppression

    NASA Astrophysics Data System (ADS)

    Zheng, Yue; Dang, Peipei; Zheng, Chuantao; Ye, Weilin; Wang, Yiding

    2016-11-01

    A miniature mid-infrared (mid-IR) methane (CH4) sensor system was developed by employing a wide-band wire-source and a semi-ellipsoid multi-pass gas cell. A dual-step differential method instead of the traditional one-step differential method was adopted by this sensor to tune measuring range/zero point and to suppress the additive/multiplicative noise. This method included a first subtraction operation between the two output signals (including a detection signal and a reference signal) from the dual-channel detector and a second subtraction operation on the amplitudes of the first-subtraction signal and the reference signal, followed by a ratio operation between the amplitude of the second-subtraction signal and the reference signal. Detailed experiments were performed to assess the performance of the sensor system. The detection range is 0-50 k ppm, and as the concentration gets larger than 12 k ppm, the relative detection error falls into the range of -3% to +3%. The Allan deviation is about 4.65 ppm with an averaging time of 1 s, and such value can be further improved to 0.45 ppm with an averaging time of 124 s. Due to the cost-effective incandescence wire-source, the small-size ellipsoid multi-pass gas cell and the miniature structure of the sensor, the developed standalone device shows potential applications of CH4 detection under coal-mine environment.

  12. Computer-Based Video Instruction to Teach Young Adults with Moderate Intellectual Disabilities to Perform Multiple Step, Job Tasks in a Generalized Setting

    ERIC Educational Resources Information Center

    Mechling, Linda C.; Ortega-Hurndon, Fanny

    2007-01-01

    This study evaluated the effectiveness of computer-based video instruction (CBVI) to teach three young adults with moderate intellectual disabilities to perform complex, multiple step, job tasks in a generalized setting. A multiple probe design across three job tasks and replicated across three students was used to evaluate the effectiveness of…

  13. Sodium phenylacetate inhibits adoptive transfer of experimental allergic encephalomyelitis in SJL/J mice at multiple steps.

    PubMed

    Dasgupta, Subhajit; Zhou, You; Jana, Malabendu; Banik, Naren L; Pahan, Kalipada

    2003-04-01

    Experimental allergic encephalomyelitis (EAE) is the animal model for multiple sclerosis. The present study underlines the importance of sodium phenylacetate (NaPA), a drug approved for urea cycle disorders, in inhibiting the disease process of adoptively transferred EAE in female SJL/J mice at multiple steps. Myelin basic protein (MBP)-primed T cells alone induced the expression of NO synthase (iNOS) and the activation of NF-kappaB in mouse microglial cells through cell-cell contact. However, pretreatment of MBP-primed T cells with NaPA markedly inhibited its ability to induce microglial expression of iNOS and activation of NF-kappaB. Consistently, adoptive transfer of MBP-primed T cells, but not that of NaPA-pretreated MBP-primed T cells, induced the clinical symptoms of EAE in female SJL/J mice. Furthermore, MBP-primed T cells isolated from NaPA-treated donor mice were also less efficient than MBP-primed T cells isolated from normal donor mice in inducing iNOS in microglial cells and transferring EAE to recipient mice. Interestingly, clinical symptoms of EAE were much less in mice receiving NaPA through drinking water than those without NaPA. Similar to NaPA, sodium phenylbutyrate, a chemically synthesized precursor of NaPA, also inhibited the disease process of EAE. Histological and immunocytochemical analysis showed that NaPA inhibited EAE-induced spinal cord mononuclear cell invasion and normalized iNOS, nitrotyrosine, and p65 (the RelA subunit of NF-kappaB) expression within the spinal cord. Taken together, our results raise the possibility that NaPA or sodium phenylbutyrate taken through drinking water or milk may reduce the observed neuroinflammation and disease process in multiple sclerosis patients.

  14. Parasites and health affect multiple sexual signals in male common wall lizards, Podarcis muralis

    NASA Astrophysics Data System (ADS)

    Martín, José; Amo, Luisa; López, Pilar

    2008-04-01

    Multiple advertising sexual traits may either advertise different characteristics of male condition or be redundant to reinforce reliability of signals. Research has focused on multiple visual traits. However, in animals that use different multiple additional sensory systems, such as chemoreception, different types of traits might have evolved to signal similar characteristics of a male quality using different sensory channels. We examined whether ventral coloration and chemicals in femoral gland secretions of male common wall lizards, Podarcis muralis, are affected by their health state (blood-parasite load and cell-mediated immune response). Our results indicated that less parasitized lizards had brighter and more yellowish ventral colorations and also femoral secretions with higher proportions of two esters of octadecenoic acid. In addition, lizards with a greater immune response had more saturated coloration and secretions with higher proportions of octadecenoic acid methyl ester. We suggest that these signals would be reliable because only healthier males seemed able to allocate more carotenoids to coloration and presumably costly chemicals to secretions. The use of multiple sensory channels may provide more opportunities to signal a male quality under different circumstances, but also may reinforce the reliability of the signal when both types of traits may be perceived simultaneously.

  15. Mechanisms of adaptation from a multiple to a single step recovery strategy following repeated exposure to forward loss of balance in older adults.

    PubMed

    Carty, Christopher P; Cronin, Neil J; Lichtwark, Glen A; Mills, Peter M; Barrett, Rod S

    2012-01-01

    When released from an initial, static, forward lean angle and instructed to recover with a single step, some older adults are able to meet the task requirements, whereas others either stumble or fall. The purpose of the present study was to use the concept of margin of stability (MoS) to investigate balance recovery responses in the anterior-posterior direction exhibited by older single steppers, multiple steppers and those that are able to adapt from multiple to single steps following exposure to repeated forward loss of balance. One hundred and fifty-one healthy, community dwelling, older adults, aged 65-80 years, participated in the study. Participants performed four trials of the balance recovery task from each of three initial lean angles. Balance recovery responses in the anterior-posterior direction were quantified at three events; cable release (CR), toe-off (TO) and foot contact (FC), for trials performed at the intermediate lean angle. MoS was computed as the anterior-posterior distance between the forward boundary of the Base of Support (BoS) and the vertical projection of the velocity adjusted centre of mass position (XCoM). Approximately one-third of participants adapted from a multiple to a single step recovery strategy following repeated exposure to the task. MoS at FC for the single and multiple step trials in the adaptation group were intermediate between the exclusively single step group and the exclusively multiple step group, with the single step trials having a significant, 3.7 times higher MoS at FC than the multiple step trials. Consistent with differences between single and multiple steppers, adaptation from multiple to single steps was attributed to an increased BoS at FC, a reduced XCoM at FC and an increased rate of BoS displacement from TO to FC. Adaptations occurred within a single test session and suggest older adults that are close to the threshold of successful recovery can rapidly improve dynamic stability following repeated

  16. A New Stochastic Multiple-Plume Eddy-Diffusivity/Mass-Flux model: A Step Towards a Unified Parameterization

    NASA Astrophysics Data System (ADS)

    Suselj, K.; Suzuki, K.; Teixeira, J.

    2014-12-01

    A new mixing parameterization for climate and weather prediction models is developed. The new parameterization represents boundary layer mixing, and non-precipitating and precipitating convection processes in a unified and physically consistent manner. The parameterization builds on a previously tested stochastic multiple-plume eddy-diffusivity/mass-flux (EDMF) approach. The new parameterization includes a realistic model for microphysical processes as part of the mass-flux parameterization, and a parameterization for convective downdrafts. A method to solve the mass-flux dynamics and microphysics simultaneously is developed. This method avoids the need for an iterative solution of the equations and is numerically stable. The new EDMF parameterization is implemented in a single-column model (SCM) and we show that the model is able to capture essential features of moist boundary layers, ranging from the stratocumulus, shallow and precipitating cumulus regimes. Detailed comparisons of a few important cases with LES results are shown to confirm the robustness of the present approach. This new parameterization provides an important step towards a fully unified parameterization of boundary layer, shallow and deep convection.

  17. The K+ battery-regulating Arabidopsis K+ channel AKT2 is under the control of multiple post-translational steps

    PubMed Central

    Michard, Erwan; Rocha, Marcio; Gomez-Porras, Judith L; González, Wendy; Corrâa, Luiz Gustavo Guedes; Ramírez-Aguilar, Santiago J; Cuin, Tracey Ann

    2011-01-01

    Potassium (K+) is an important nutrient for plants. It serves as a cofactor of various enzymes and as the major inorganic solute maintaining plant cell turgor. In a recent study, an as yet unknown role of K+ in plant homeostasis was shown. It was demonstrated that K+ gradients in vascular tissues can serve as an energy source for phloem (re)loading processes and that the voltage-gated K+ channels of the AKT2-type play a unique role in this process. The AKT2 channel can be converted by phosphorylation of specific serine residues (S210 and S329) into a non-rectifying channel that allows a rapid efflux of K+ from the sieve element/companion cells (SE/CC) complex. The energy of this flux is used by other transporters for phloem (re)loading processes. Nonetheless, the results do indicate that post-translational modifications at S210 and S329 alone cannot explain AKT2 regulation. Here, we discuss the existence of multiple post-translational modification steps that work in concert to convert AKT2 from an inward-rectifying into a non-rectifying K+ channel. PMID:21445013

  18. Interprofessional, multiple step simulation course improves pediatric resident and nursing staff management of pediatric patients with diabetic ketoacidosis

    PubMed Central

    Larson-Williams, Linnea M; Youngblood, Amber Q; Peterson, Dawn Taylor; Zinkan, J Lynn; White, Marjorie L; Abdul-Latif, Hussein; Matalka, Leen; Epps, Stephen N; Tofil, Nancy M

    2016-01-01

    AIM To investigate the use of a multidisciplinary, longitudinal simulation to educate pediatric residents and nurses on management of pediatric diabetic ketoacidosis. METHODS A multidisciplinary, multiple step simulation course was developed by faculty and staff using a modified Delphi method from the Pediatric Simulation Center and pediatric endocrinology department. Effectiveness of the simulation for the residents was measured with a pre- and post-test and a reference group not exposed to simulation. A follow up post-test was completed 3-6 mo after the simulation. Nurses completed a survey regarding the education activity. RESULTS Pediatric and medicine-pediatric residents (n = 20) and pediatric nurses (n = 25) completed the simulation course. Graduating residents (n = 16) were used as reference group. Pretest results were similar in the control and intervention group (74% ± 10% vs 76% ± 15%, P = 0.658). After completing the intervention, participants improved in the immediate post-test in comparison to themselves and the control group (84% ± 12% post study; P < 0.05). The 3-6 mo follow up post-test results demonstrated knowledge decay when compared to their immediate post-test results (78% ± 14%, P = 0.761). Residents and nurses felt the interdisciplinary and longitudinal nature of the simulation helped with learning. CONCLUSION Results suggest a multidisciplinary, longitudinal simulation improves immediate post-intervention knowledge but important knowledge decay occurs, future studies are needed to determine ways to decrease this decay. PMID:27896145

  19. Multiple sublethal chemicals negatively affect tadpoles of the green frog, Rana clamitans

    USGS Publications Warehouse

    Boone, Michelle D.; Bridges, Christine M.; Fairchild, James F.; Little, Edward E.

    2005-01-01

    Many habitats may be exposed to multiple chemical contaminants, particularly in agricultural areas where fertilizer and pesticide use are common; however, the singular and interactive effects of contaminants are not well understood. The objective of our study was to examine how realistic, sublethal environmental levels of ammonium nitrate fertilizer (0, 10, 20 mg/L and ammonium chloride control) and the common insecticide carbaryl (0 or 2.5 mg/L) individually and interactively affect the development, size, and survival of green frog (Rana clamitans) tadpoles. We reared tadpoles for 95 d in outdoor 1,000-L polyethylene ponds. We found that the combination of carbaryl and nitrate had a negative effect on development and mass of tadpoles compared to the positive effect that either contaminant had alone. Presence of carbaryl was generally associated with short-term increases in algal resources, including ponds exposed to both carbaryl and nitrate. However, with exposure to nitrate and carbaryl, tadpole mass and development were not positively affected as with one chemical stressor alone. The combination of these sublethal contaminants may reduce the ability of amphibians to benefit from food-rich environments or have metabolic costs. Our study demonstrates the importance of considering multiple stressors when evaluating population-level responses.

  20. Walk Ratio (Step Length/Cadence) as a Summary Index of Neuromotor Control of Gait: Application to Multiple Sclerosis

    ERIC Educational Resources Information Center

    Rota, Viviana; Perucca, Laura; Simone, Anna; Tesio, Luigi

    2011-01-01

    In healthy adults, the step length/cadence ratio [walk ratio (WR) in mm/(steps/min) and normalized for height] is known to be constant around 6.5 mm/(step/min). It is a speed-independent index of the overall neuromotor gait control, in as much as it reflects energy expenditure, balance, between-step variability, and attentional demand. The speed…

  1. Multiple step growth of single crystalline rutile nanorods with the assistance of self-assembled monolayer for dye sensitized solar cells.

    PubMed

    Yang, Mengjin; Neupane, Suman; Wang, Xuewen; He, Jin; Li, Wenzhi; Pala, Nezih

    2013-10-09

    A novel multiple step growth (MSG) process has been developed to synthesize rutile nanorods (NRs) on fluorine-doped tin oxide (FTO) glass with the assistance of a self-assembled monolayer (SAM) aiming to increase the internal surface area of the 1D materials for dye sensitized solar cell (DSSC) applications. The experimental result reveals that the SAM layer can be selectively decomposed at the tip of the nanorod, namely the rutile (001) surface, due to the anisotropic photocatalytic property of the rutile. The remaining SAM layer on the side-wall of the NRs remains intact and serves as water repellent which prevents the radial growth of the NRs during the next step hydrothermal synthesis; therefore, the spacing between the NRs and the porosity of the NR array can be retained after additional growth cycles. On the other hand, introduction of a middle layer formed via TiCl4 solution treatment before the next growth cycle is found to be an effective way to control the diameters of the newly grown NRs. The performance of DSSC made from the rutile NRs grown using the MSG technique has been examined, and it is significantly affected by the internal surfaces of the NRs. Furthermore, the MSG combined with NR etching treatment by acid at low temperature (150 °C) leads to a significant enhancement in the solar cell performance. The gigantic wettability difference of the NRs before and after the SAM treatment as well as the MSG method could be adapted to prepare superhydrophobic and superhydrophilic nanostructured patterns for other applications.

  2. Multiple Steps of Phosphorylation of Activated Rhodopsin Can Account for the Reproducibility of Vertebrate Rod Single-photon Responses

    PubMed Central

    Hamer, R.D.; Nicholas, S.C.; Tranchina, D.; Liebman, P.A.; Lamb, T.D.

    2003-01-01

    of integrated R* activity, and cannot be used to estimate the minimum number of R* inactivation steps. We conclude that multiple phosphorylation-dependent decrements in R* activity (with Arr-quench) can confer the observed reproducibility of rod SPRs; there is no compelling need to invoke a long series of non-phosphorylation dependent state changes in R* (as in Rieke, F., and D.A. Baylor. 1998a. Biophys. J. 75:1836–1857; Field, G.D., and F. Rieke. 2002. Neuron. 35:733–747.). Our analyses, plus data and modeling of others (Rieke, F., and D.A. Baylor. 1998a. Biophys. J. 75:1836–1857; Field, G.D., and F. Rieke. 2002. Neuron. 35:733–747.), also argue strongly against either feedback (including Ca2+-feedback) or depletion of any molecular species downstream to R* as the dominant cause of SPR reproducibility. PMID:12975449

  3. Psychotic-affective symptoms and multiple system atrophy expand phenotypes of spinocerebellar ataxia type 2.

    PubMed

    Chen, Kai-Hsiang; Lin, Chin-Hsien; Wu, Ruey-Meei

    2012-03-20

    Spinocerebellar ataxia type 2 (SCA2) is a progressive neurodegenerative disorder, characterised by ataxic gait, slow saccades and peripheral neuropathy. Levodopa-responsive parkinsonism could be a clinical phenotype of SCA2, especially those of Chinese origin. In addition to these motor symptoms, SCA2 has been associated with depression and cognitive dysfunction, with only rare reports of psychosis. The authors report the presence of severe psychosis, major depression and multiple system atrophy in affected subjects of a Taiwanese family with intermediate CAG repeats within the ATXN2 gene. The identification of this rare and distinctive SCA2 phenotype expands the current knowledge of the phenotypic variability of SCA2 and suggests that modifier genes could influence the clinical phenotype of SCA2.

  4. Eating in groups: Do multiple social influences affect intake in a fast-food restaurant?

    PubMed

    Brindal, Emily; Wilson, Carlene; Mohr, Philip; Wittert, Gary

    2015-05-01

    This study investigated multiple social influences to determine whether they affect amount eaten at a fast-food environment. Using observational methods, data on meal duration, foods eaten and personal characteristics were collected for 157 McDonald's patrons. Analysis of covariance revealed that female diners ate less kilojoules when eating in mixed- versus same-sex groups (adjusted difference = 967 kJ, p < .05), while male diners eating in mixed-sex company ate more in groups compared to pairs (adjusted difference = 1067 kJ, p = .019). Influences to increase and restrict the amount eaten can operate simultaneously in an eating environment with gender a critical factor for consideration.

  5. Detecting Differential Item Functioning in the Japanese Version of the Multiple Affect Adjective Check List--Revised

    ERIC Educational Resources Information Center

    Yasuda, Tomoyuki; Lei, Pui-Wa; Suen, Hoi K.

    2007-01-01

    This study examines the differential item functioning (DIF) of the English version and the Japanese-translated version of the Multiple Affect Adjective Check List--Revised (MAACL-R) using the logistic regression (LR) procedure. The results of the LR are supplemented by multiple group confirmatory factor analysis (MGCFA). A total of five items are…

  6. Use of multiple correspondence analysis (MCA) to identify interactive meteorological conditions affecting relative throughfall

    NASA Astrophysics Data System (ADS)

    Van Stan, John T.; Gay, Trent E.; Lewis, Elliott S.

    2016-02-01

    Forest canopies alter rainfall reaching the surface by redistributing it as throughfall. Throughfall supplies water and nutrients to a variety of ecohydrological components (soil microbial communities, stream water discharge/chemistry, and stormflow pathways) and is controlled by canopy structural interactions with meteorological conditions across temporal scales. This work introduces and applies multiple correspondence analyses (MCAs) to a range of meteorological thresholds (median intensity, median absolute deviation (MAD) of intensity, median wind-driven droplet inclination angle, and MAD of wind speed) for an example throughfall problem: identification of interacting storm conditions corresponding to temporal concentration in relative throughfall beyond the median observation (⩾73% of rain). MCA results from the example show that equalling or exceeding rain intensity thresholds (median and MAD) corresponded with temporal concentration of relative throughfall across all storms. Under these intensity conditions, two wind mechanisms produced significant correspondences: (1) high, steady wind-driven droplet inclination angles increased surface wetting; and (2) sporadic winds shook entrained droplets from surfaces. A discussion is provided showing that these example MCA findings agree well with previous work relying on more historically common methods (e.g., multiple regression and analytical models). Meteorological threshold correspondences to temporal concentration of relative throughfall at our site may be a function of heavy Tillandsia usneoides coverage. Applications of MCA within other forests may provide useful insights to how temporal throughfall dynamics are affected for drainage pathways dependent on different structures (leaves, twigs, branches, etc.).

  7. Do You Know What I Feel? A First Step towards a Physiological Measure of the Subjective Well-Being of Persons with Profound Intellectual and Multiple Disabilities

    ERIC Educational Resources Information Center

    Vos, Pieter; De Cock, Paul; Petry, Katja; Van Den Noortgate, Wim; Maes, Bea

    2010-01-01

    Background: Because of limited communicative skills, it is not self-evident to measure subjective well-being in people with profound intellectual and multiple disabilities. As a first step towards a non-interpretive measure of subjective well-being, we explored how the respiratory, cardiovascular and electro dermal response systems were associated…

  8. CB1 receptor affects cortical plasticity and response to physiotherapy in multiple sclerosis

    PubMed Central

    Mori, Francesco; Ljoka, Concetta; Nicoletti, Carolina G.; Kusayanagi, Hajime; Buttari, Fabio; Giordani, Laura; Rossi, Silvia; Foti, Calogero

    2014-01-01

    Objectives: Therapeutic effects of physical therapy in neurologic disorders mostly rely on the promotion of use-dependent synaptic plasticity in damaged neuronal circuits. Genetic differences affecting the efficiency of synaptic plasticity mechanisms could explain why some patients do not respond adequately to the treatment. It is known that physical exercise activates the endocannabinoid system and that stimulation of cannabinoid CB1 receptors (CB1Rs) promotes synaptic plasticity in both rodents and humans. We thus tested whether CB1R genetic variants affect responsiveness to exercise therapy. Methods: We evaluated the effect of a genetic variant of the CB1R associated with reduced receptor expression (patients with long AAT trinucleotide short tandem repeats in the CNR1 gene) on long-term potentiation (LTP)–like cortical plasticity induced by transcranial magnetic theta burst stimulation (TBS) of the motor cortex and, in parallel, on clinical response to exercise therapy in patients with multiple sclerosis. Results: We found that patients with long AAT CNR1 repeats do not express TBS-induced LTP-like cortical plasticity and show poor clinical benefit after exercise therapy. Conclusions: Our results provide the first evidence that genetic differences within the CB1R may influence clinical responses to exercise therapy, and they strengthen the hypothesis that CB1Rs are involved in the regulation of synaptic plasticity and in the control of spasticity in humans. This information might be of great relevance for patient stratification and personalized rehabilitation treatment programs. PMID:25520956

  9. Affective Temperament Profiles in Patients with Multiple Sclerosis: Association with Mood Disorders

    PubMed Central

    ÖZKAN, Adile; ALTINBAŞ, Kürşat; KOÇ, Emine Rabia; ŞEN, Halil Murat; ÖZIŞIK KARAMAN, Handan Işın

    2016-01-01

    Introduction The aim of the present study was to screen for bipolarity and to investigate the affective temperaments of patients with multiple sclerosis (MS) and the possible association between the clinical and demographic characteristics of MS patients and temperament profiles. Methods A total of 65 patients with MS and 66 healthy volunteers completed the 32-item hypomania checklist (HCl-32), the Mood Disorder Questionnaire (MDQ), and the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego-Autoquestionnaire (TEMPS-A) tests. The HCl-32, MDQ, and TEMPS-A scores were compared between the patients and healthy volunteers. Results MS patients had significantly higher scores for the depressive, cyclothymic, irritable, and anxious domains of the TEMPS-A scale than the control group, whereas relapsing remitting MS (RRMS) patients had higher MDQ and TEMPS-A hyperthymia scores than secondary progressive MS patients. MS patients who were being treated with interferon beta 1-b therapy had significantly higher MDQ scores than those being treated with interferon beta 1-a, glatiramer acetate, or who were without medication. Expanded Disability Status Scale (EDSS) scores were positively correlated with TEMPS-A depressive and hyperthymic temperaments. Conclusion Our results suggest that higher scores for affective temperament in MS patients indicate subclinical manifestations of mood disorders. Higher hyperthymia scores and manic symptoms detected in the RRMS group could shed light on the relationship between bipolarity and MS. Thus, the screening of bipolarity and affective temperament profiles in MS patients could help clinicians predict future mood episodes and decrease their impact on disease severity. PMID:28360804

  10. Multiple Polymorphisms Affect Expression and Function of the Neuropeptide S Receptor (NPSR1)

    PubMed Central

    Anedda, Francesca; Zucchelli, Marco; Schepis, Danika; Hellquist, Anna; Corrado, Lucia; D'Alfonso, Sandra; Achour, Adnane; McInerney, Gerald; Bertorello, Alejandro; Lördal, Mikael; Befrits, Ragnar; Björk, Jan; Bresso, Francesca; Törkvist, Leif; Halfvarson, Jonas

    2011-01-01

    Background neuropeptide S (NPS) and its receptor NPSR1 act along the hypothalamic-pituitary-adrenal axis to modulate anxiety, fear responses, nociception and inflammation. The importance of the NPS-NPSR1 signaling pathway is highlighted by the observation that, in humans, NPSR1 polymorphism associates with asthma, inflammatory bowel disease, rheumatoid arthritis, panic disorders, and intermediate phenotypes of functional gastrointestinal disorders. Because of the genetic complexity at the NPSR1 locus, however, true causative variations remain to be identified, together with their specific effects on receptor expression or function. To gain insight into the mechanisms leading to NPSR1 disease-predisposing effects, we performed a thorough functional characterization of all NPSR1 promoter and coding SNPs commonly occurring in Caucasians (minor allele frequency >0.02). Principal Findings we identified one promoter SNP (rs2530547 [−103]) that significantly affects luciferase expression in gene reporter assays and NPSR1 mRNA levels in human leukocytes. We also detected quantitative differences in NPS-induced genome-wide transcriptional profiles and CRE-dependent luciferase activities associated with three NPSR1 non-synonymous SNPs (rs324981 [Ile107Asn], rs34705969 [Cys197Phe], rs727162 [Arg241Ser]), with a coding variant exhibiting a loss-of-function phenotype (197Phe). Potential mechanistic explanations were sought with molecular modelling and bioinformatics, and a pilot study of 2230 IBD cases and controls provided initial support to the hypothesis that different cis-combinations of these functional SNPs variably affect disease risk. Significance these findings represent a first step to decipher NPSR1 locus complexity and its impact on several human conditions NPS antagonists have been recently described, and our results are of potential pharmacogenetic relevance. PMID:22216302

  11. Multiple Factors Affect Socioeconomics and Wellbeing of Artisanal Sea Cucumber Fishers

    PubMed Central

    Ngaluafe, Poasi; Foale, Simon J.; Cocks, Nicole; Cullis, Brian R.; Lalavanua, Watisoni

    2016-01-01

    Small-scale fisheries are important to livelihoods and subsistence seafood consumption of millions of fishers. Sea cucumbers are fished worldwide for export to Asia, yet few studies have assessed factors affecting socioeconomics and wellbeing among fishers. We interviewed 476 men and women sea cucumber fishers at multiple villages within multiple locations in Fiji, Kiribati, Tonga and New Caledonia using structured questionnaires. Low rates of subsistence consumption confirmed a primary role of sea cucumbers in income security. Prices of sea cucumbers sold by fishers varied greatly among countries, depending on the species. Gender variation in landing prices could be due to women catching smaller sea cucumbers or because some traders take advantage of them. Dissatisfaction with fishery income was common (44% of fishers), especially for i-Kiribati fishers, male fishers, and fishers experiencing difficulty selling their catch, but was uncorrelated with sale prices. Income dissatisfaction worsened with age. The number of livelihood activities averaged 2.2–2.5 across countries, and varied significantly among locations. Sea cucumbers were often a primary source of income to fishers, especially in Tonga. Other common livelihood activities were fishing other marine resources, copra production in Kiribati, agriculture in Fiji, and salaried jobs in New Caledonia. Fishing other coastal and coral reef resources was the most common fall-back livelihood option if fishers were forced to exit the fishery. Our data highlight large disparities in subsistence consumption, gender-related price equity, and livelihood diversity among parallel artisanal fisheries. Improvement of supply chains in dispersed small-scale fisheries appears as a critical need for enhancing income and wellbeing of fishers. Strong evidence for co-dependence among small-scale fisheries, through fall-back livelihood preferences of fishers, suggests that resource managers must mitigate concomitant effects on

  12. Do Physical Therapy Interventions Affect Urinary Incontinence and Quality of Life in People with Multiple Sclerosis?

    PubMed Central

    Rivera, Monica; Melnick, Marsha; Allen, Diane D.

    2015-01-01

    Background: Multiple sclerosis (MS) presents with many debilitating symptoms, including urinary incontinence (UI), that physical therapy (PT) may address; UI is widely prevalent, but PT management of symptoms lacks consensus. A meta-analysis of long-term nonsurgical and nonpharmaceutical treatment options may supply this deficiency. We analyzed the current evidence for effectiveness of PT to decrease UI and improve quality of life (QOL) in people with MS. Methods: An electronic search conducted through November 26, 2013, included the following search terms: incontinence, bladder dysfunction, urinary incontinence, multiple sclerosis, MS, physical therapy, physiotherapy, therapy, and rehabilitation. Criteria for inclusion were as follows: MS diagnosis, intervention involved PT for UI or bladder dysfunction, outcomes assessed QOL or UI, and at least a 4 of 10 on the Physiotherapy Evidence Database scale or a 2b level of evidence. Outcomes were combined across studies, and effect sizes are depicted in forest plots. Results: Six studies met the inclusion criteria. Between-group analysis revealed statistically significant differences in incontinence episodes and QOL, but did not reach significance for functional control mechanisms (eg, electromyography data on strength of contraction, relaxation, and endurance). Incontinence leakage episodes and QOL participation improved within groups. Conclusions: Meta-analysis indicates support for PT for minimizing incontinence compared with pretreatment and affecting incontinence and QOL more than control in people with MS. Protocols were heterogeneous regarding duration and type of PT intervention and were applied in different types of MS. Further research may reveal the most effective combination and variety of PT interventions for people with MS. PMID:26300703

  13. Multiple Factors Affect Socioeconomics and Wellbeing of Artisanal Sea Cucumber Fishers.

    PubMed

    Purcell, Steven W; Ngaluafe, Poasi; Foale, Simon J; Cocks, Nicole; Cullis, Brian R; Lalavanua, Watisoni

    2016-01-01

    Small-scale fisheries are important to livelihoods and subsistence seafood consumption of millions of fishers. Sea cucumbers are fished worldwide for export to Asia, yet few studies have assessed factors affecting socioeconomics and wellbeing among fishers. We interviewed 476 men and women sea cucumber fishers at multiple villages within multiple locations in Fiji, Kiribati, Tonga and New Caledonia using structured questionnaires. Low rates of subsistence consumption confirmed a primary role of sea cucumbers in income security. Prices of sea cucumbers sold by fishers varied greatly among countries, depending on the species. Gender variation in landing prices could be due to women catching smaller sea cucumbers or because some traders take advantage of them. Dissatisfaction with fishery income was common (44% of fishers), especially for i-Kiribati fishers, male fishers, and fishers experiencing difficulty selling their catch, but was uncorrelated with sale prices. Income dissatisfaction worsened with age. The number of livelihood activities averaged 2.2-2.5 across countries, and varied significantly among locations. Sea cucumbers were often a primary source of income to fishers, especially in Tonga. Other common livelihood activities were fishing other marine resources, copra production in Kiribati, agriculture in Fiji, and salaried jobs in New Caledonia. Fishing other coastal and coral reef resources was the most common fall-back livelihood option if fishers were forced to exit the fishery. Our data highlight large disparities in subsistence consumption, gender-related price equity, and livelihood diversity among parallel artisanal fisheries. Improvement of supply chains in dispersed small-scale fisheries appears as a critical need for enhancing income and wellbeing of fishers. Strong evidence for co-dependence among small-scale fisheries, through fall-back livelihood preferences of fishers, suggests that resource managers must mitigate concomitant effects on other

  14. BDNF val66met Polymorphism Affects Aging of Multiple Types of Memory

    PubMed Central

    Kennedy, Kristen M.; Reese, Elizabeth D.; Horn, Marci M.; Sizemore, April N.; Unni, Asha K.; Meerbrey, Michael E.; Kalich, Allan G.; Rodrigue, Karen M.

    2014-01-01

    The BDNF val66met polymorphism (rs6265) influences activity-dependent secretion of brain-derived neurotrophic factor in the synapse, which is crucial for learning and memory. Individuals homozygous or heterozygous for the met allele have lower BDNF secretion than val homozygotes and may be at risk for reduced declarative memory performance, but it remains unclear which types of declarative memory may be affected and how aging of memory across the lifespan is impacted by the BDNF val66met polymorphism. This cross-sectional study investigated the effects of BDNF polymorphism on multiple indices of memory (item, associative, prospective, subjective complaints) in a lifespan sample of 116 healthy adults aged 20-93 years. Advancing age showed a negative effect on item, associative and prospective memory, but not on subjective memory complaints. For item and prospective memory, there were significant age x BDNF group interactions, indicating the adverse effect of age on memory performance across the lifespan was much stronger in the BDNF met carriers than for the val homozygotes. BDNF met carriers also endorsed significantly greater subjective memory complaints, regardless of age, and showed a trend (p < .07) toward poorer associative memory performance compared to val homozygotes. These results suggest that genetic predisposition to the availability of brain-derived neurotrophic factor, by way of the BDNF val66met polymorphism, exerts an influence on multiple indices of episodic memory – in some cases in all individuals regardless of age (subjective memory and perhaps associative memory), in others as an exacerbation of age-related differences in memory across the lifespan (item and prospective memory). PMID:25264352

  15. How proprioceptive impairments affect quiet standing in patients with multiple sclerosis.

    PubMed

    Rougier, P; Faucher, M; Cantalloube, S; Lamotte, D; Vinti, M; Thoumie, P

    2007-01-01

    To assess if multiple sclerosis patients with proprioceptive impairment are specifically affected during quiet standing with eyes open and how they can develop motor compensatory processes, 56 patients, classified from sensory clinical tests as ataxo-spastic (MS-AS) or only having spasticity (MS-S), were compared to 23 healthy adults matched for age. The postural strategies were assessed from the centre-of-pressure trajectories (CP), measured from a force platform in the eyes open standing condition for a single trial lasting 51.2 s. The vertical projection of the centre of gravity (CGv) and its vertical difference from the CP (CP-CGv) were then estimated through a biomechanical relationship. These two movements permit the characterization of the postural performance and the horizontal acceleration communicated to the CG and from that, the global energy expenditure, respectively. Both MS-AS and MS-S groups demonstrate larger CGv and CP-CGv movements than healthy individuals of the same age. Whilst similar CGv values are noticed in both MS subgroups, suggesting similar postural performances, statistically significant differences are observed for the CP-CGv component. Biomechanically, this feature expresses the necessity for the MS-AS group to develop augmented neuro-muscular means to control their body movements, as compared to the MS-S group. By demonstrating for both groups of patients similar postural performance accompanied by a varying degree of energy expenditure to maintain undisturbed upright stance, this study reveals that MS-AS patients which are affected by proprioceptive loss can compensate for this deficit with more efficient control strategies, when standing still with their eyes open.

  16. A split-step method to include electron–electron collisions via Monte Carlo in multiple rate equation simulations

    SciTech Connect

    Huthmacher, Klaus; Molberg, Andreas K.; Rethfeld, Bärbel; Gulley, Jeremy R.

    2016-10-01

    A split-step numerical method for calculating ultrafast free-electron dynamics in dielectrics is introduced. The two split steps, independently programmed in C++11 and FORTRAN 2003, are interfaced via the presented open source wrapper. The first step solves a deterministic extended multi-rate equation for the ionization, electron–phonon collisions, and single photon absorption by free-carriers. The second step is stochastic and models electron–electron collisions using Monte-Carlo techniques. This combination of deterministic and stochastic approaches is a unique and efficient method of calculating the nonlinear dynamics of 3D materials exposed to high intensity ultrashort pulses. Results from simulations solving the proposed model demonstrate how electron–electron scattering relaxes the non-equilibrium electron distribution on the femtosecond time scale.

  17. A split-step method to include electron-electron collisions via Monte Carlo in multiple rate equation simulations

    NASA Astrophysics Data System (ADS)

    Huthmacher, Klaus; Molberg, Andreas K.; Rethfeld, Bärbel; Gulley, Jeremy R.

    2016-10-01

    A split-step numerical method for calculating ultrafast free-electron dynamics in dielectrics is introduced. The two split steps, independently programmed in C++11 and FORTRAN 2003, are interfaced via the presented open source wrapper. The first step solves a deterministic extended multi-rate equation for the ionization, electron-phonon collisions, and single photon absorption by free-carriers. The second step is stochastic and models electron-electron collisions using Monte-Carlo techniques. This combination of deterministic and stochastic approaches is a unique and efficient method of calculating the nonlinear dynamics of 3D materials exposed to high intensity ultrashort pulses. Results from simulations solving the proposed model demonstrate how electron-electron scattering relaxes the non-equilibrium electron distribution on the femtosecond time scale.

  18. Improved characteristics of ultraviolet AlGaN multiple-quantum-well laser diodes with step-graded quantum barriers close to waveguide layers

    NASA Astrophysics Data System (ADS)

    Cai, Xuefen; Li, Shuping; Kang, Junyong

    2016-09-01

    Ultraviolet AlGaN multiple-quantum-well laser diodes (LDs) with step-graded quantum barriers (QBs) instead of conventional first and last QBs close to waveguide layers are proposed. The characteristics of this type of laser diodes are numerically investigated by using the software PICS3D and it is found that the performances of these LDs are greatly improved. The results indicates that the structure with step-graded QBs exhibits higher output light power, slope efficiency and emission intensity, as well as lower series resistance and threshold current density under the identical condition, compared with conventional LD structure.

  19. The dynamics of finger tremor in multiple sclerosis is affected by whole body position.

    PubMed

    Morrison, S; Sosnoff, J J; Sandroff, B M; Pula, J H; Motl, R W

    2013-01-15

    Multiple sclerosis (MS) is a disease that results in widespread damage to the nervous system. One consequence of this disease is the emergence of enhanced tremor. This study was designed to (1) compare the tremor responses of persons with MS to that of healthy adults and to (2) examine the impact of whole body position (i.e., seated/standing) on tremor. Bilateral postural tremor was recorded using accelerometers attached to each index finger. Results revealed some similarity of tremor between groups in regard to the principal features (e.g., presence of peaks in similar frequency ranges). However, significant differences were observed with tremor for the MS persons being of greater amplitude, more regular (lower ApEn) and more strongly coupled across limbs compared to the elderly. The effects of body position were consistent across all subjects, with tremor increasing significantly from sitting-to-standing. However, the tremor increase for the MS group was greater than the elderly. Overall, the tremor for MS group was negatively affected by both this disease process and the nature of the task being performed. This latter result indicates that tremor does not simply reflect the feed-forward output of the neuromotor system but that it is influenced by the task constraints.

  20. Benthic macroinvertebrate communities affected by multiple stressors within tidal creeks in northeastern USA harbors

    SciTech Connect

    Papageorgis, C.; Murray, M.; Danis, C.; Yates, L.

    1995-12-31

    Surveys of water quality, substrate quality and benthic macroinvertebrates were conducted in a variety of tidal creeks located in the vicinity of a municipal solid waste landfill prior to the construction of a leachate collection system. In-Situ water quality data indicated high water temperatures and low dissolved oxygen values along with high turbidites. Sediment chemistry data indicated that all sediment within the study area exceed USEPA heavy metal criteria. Grain size and salinity data indicate that the study area lies within the Mesohaline Mud habitat class. Water quality data remained within similar concentrations with respect to indicators of leachate. The benthic macroinvertebrate community was consistently dominated by opportunistic Polychaete and Oligochaete worms. Both Shannon diversity and Rarefaction curves were used to evaluate trends in species diversity over time. The study includes a comparison to data obtained by USEPA R-EMAP monitoring programs. While large scale biomonitoring programs do not focus on small tidal creeks this study provides useful data regarding baseline benthic communities within tidal creeks affected by multiple stressors to include previous exposure and potential exposure to oil spills, continued point and non-point municipal and industrial wastewater discharges and physical stressors such as elevated water temperatures, homogeneous silt/clay substrate, and depressed dissolved oxygen values.

  1. Multiple and diverse structural changes affect the breakpoint regions of polymorphic inversions across the Drosophila genus.

    PubMed

    Puerma, Eva; Orengo, Dorcas J; Aguadé, Montserrat

    2016-10-26

    Chromosomal polymorphism is widespread in the Drosophila genus, with extensive evidence supporting its adaptive character in diverse species. Moreover, inversions are the major contributors to the genus chromosomal evolution. The molecular characterization of a reduced number of polymorphic inversion breakpoints in Drosophila melanogaster and Drosophila subobscura supports that their inversions would have mostly originated through a mechanism that generates duplications -staggered double-strand breaks- and has thus the potential to contribute to their adaptive character. There is also evidence for inversion breakpoint reuse at different time scales. Here, we have characterized the breakpoints of two inversions of D. subobscura -O4 and O8- involved in complex arrangements that are frequent in the warm parts of the species distribution area. The duplications detected at their breakpoints are consistent with their origin through the staggered-break mechanism, which further supports it as the prevalent mechanism in D. subobscura. The comparative analysis of inversions breakpoint regions across the Drosophila genus has revealed several genes affected by multiple disruptions due not only to inversions but also to single-gene transpositions and duplications.

  2. Multiple and diverse structural changes affect the breakpoint regions of polymorphic inversions across the Drosophila genus

    PubMed Central

    Puerma, Eva; Orengo, Dorcas J.; Aguadé, Montserrat

    2016-01-01

    Chromosomal polymorphism is widespread in the Drosophila genus, with extensive evidence supporting its adaptive character in diverse species. Moreover, inversions are the major contributors to the genus chromosomal evolution. The molecular characterization of a reduced number of polymorphic inversion breakpoints in Drosophila melanogaster and Drosophila subobscura supports that their inversions would have mostly originated through a mechanism that generates duplications —staggered double-strand breaks— and has thus the potential to contribute to their adaptive character. There is also evidence for inversion breakpoint reuse at different time scales. Here, we have characterized the breakpoints of two inversions of D. subobscura —O4 and O8— involved in complex arrangements that are frequent in the warm parts of the species distribution area. The duplications detected at their breakpoints are consistent with their origin through the staggered-break mechanism, which further supports it as the prevalent mechanism in D. subobscura. The comparative analysis of inversions breakpoint regions across the Drosophila genus has revealed several genes affected by multiple disruptions due not only to inversions but also to single-gene transpositions and duplications. PMID:27782210

  3. Sprint running: how changes in step frequency affect running mechanics and leg spring behaviour at maximal speed.

    PubMed

    Monte, Andrea; Muollo, Valentina; Nardello, Francesca; Zamparo, Paola

    2017-02-01

    The purpose of this study was to investigate the changes in selected biomechanical variables in 80-m maximal sprint runs while imposing changes in step frequency (SF) and to investigate if these adaptations differ based on gender and training level. A total of 40 athletes (10 elite men and 10 women, 10 intermediate men and 10 women) participated in this study; they were requested to perform 5 trials at maximal running speed (RS): at the self-selected frequency (SFs) and at SF ±15% and ±30%SFs. Contact time (CT) and flight time (FT) as well as step length (SL) decreased with increasing SF, while kvert increased with it. At SFs, kleg was the lowest (a 20% decrease at ±30%SFs), while RS was the largest (a 12% decrease at ±30%SFs). Only small changes (1.5%) in maximal vertical force (Fmax) were observed as a function of SF, but maximum leg spring compression (ΔL) was largest at SFs and decreased by about 25% at ±30%SFs. Significant differences in Fmax, Δy, kleg and kvert were observed as a function of skill and gender (P < 0.001). Our results indicate that RS is optimised at SFs and that, while kvert follows the changes in SF, kleg is lowest at SFs.

  4. Lighten up: Specific postural instructions affect axial rigidity and step initiation in patients with Parkinson’s disease

    PubMed Central

    Cohen, Rajal G.; Gurfinkel, Victor S.; Kwak, Elizabeth; Warden, Amelia C.; Horak, Fay B.

    2015-01-01

    Background Parkinson’s disease (PD) is associated with stooped postural alignment, increased postural sway, and reduced mobility. The Alexander Technique (AT) is a mindfulness-based approach to improving posture and mobility by reducing muscular interference while maintaining upward intentions. Evidence suggests that AT can reduce disability associated with PD, but a mechanism for this effect has not yet been established. Objective We investigated whether AT-based instructions reduce axial rigidity and increase upright postural alignment, and whether these instructions have different effects on postural alignment, axial rigidity, postural sway, and mobility than effort-based instructions regarding posture. Method Twenty subjects with PD practiced two sets of instructions and then attempted to implement both approaches (as well as a relaxed control condition) during quiet standing and step initiation. The ‘Lighten Up’ instructions relied on AT principles of reducing excess tension while encouraging length. The ‘Pull Up’ instructions relied on popular concepts of effortful posture correction. We measured kinematics, resistance to axial rotation, and ground reaction forces. Results Both sets of experimental instructions led to increases in upright postural alignment relative to the control condition. Only the Lighten Up instructions led to reduced postural sway, reduced axial postural tone, greater modifiability of tone, and a smoother center of pressure trajectory during step initiation, possibly indicating greater movement efficiency. Conclusion Mindful movement approaches such as AT may benefit balance and mobility in subjects with PD by acutely facilitating increased upright postural alignment while decreasing rigidity. PMID:25665828

  5. Accurate molecular dynamics and nuclear quantum effects at low cost by multiple steps in real and imaginary time: Using density functional theory to accelerate wavefunction methods

    NASA Astrophysics Data System (ADS)

    Kapil, V.; VandeVondele, J.; Ceriotti, M.

    2016-02-01

    The development and implementation of increasingly accurate methods for electronic structure calculations mean that, for many atomistic simulation problems, treating light nuclei as classical particles is now one of the most serious approximations. Even though recent developments have significantly reduced the overhead for modeling the quantum nature of the nuclei, the cost is still prohibitive when combined with advanced electronic structure methods. Here we present how multiple time step integrators can be combined with ring-polymer contraction techniques (effectively, multiple time stepping in imaginary time) to reduce virtually to zero the overhead of modelling nuclear quantum effects, while describing inter-atomic forces at high levels of electronic structure theory. This is demonstrated for a combination of MP2 and semi-local DFT applied to the Zundel cation. The approach can be seamlessly combined with other methods to reduce the computational cost of path integral calculations, such as high-order factorizations of the Boltzmann operator or generalized Langevin equation thermostats.

  6. Accurate molecular dynamics and nuclear quantum effects at low cost by multiple steps in real and imaginary time: Using density functional theory to accelerate wavefunction methods

    SciTech Connect

    Kapil, V.; Ceriotti, M.; VandeVondele, J.

    2016-02-07

    The development and implementation of increasingly accurate methods for electronic structure calculations mean that, for many atomistic simulation problems, treating light nuclei as classical particles is now one of the most serious approximations. Even though recent developments have significantly reduced the overhead for modeling the quantum nature of the nuclei, the cost is still prohibitive when combined with advanced electronic structure methods. Here we present how multiple time step integrators can be combined with ring-polymer contraction techniques (effectively, multiple time stepping in imaginary time) to reduce virtually to zero the overhead of modelling nuclear quantum effects, while describing inter-atomic forces at high levels of electronic structure theory. This is demonstrated for a combination of MP2 and semi-local DFT applied to the Zundel cation. The approach can be seamlessly combined with other methods to reduce the computational cost of path integral calculations, such as high-order factorizations of the Boltzmann operator or generalized Langevin equation thermostats.

  7. Distribution and evolution of multiple-step phosphorelay in prokaryotes: lateral domain recruitment involved in the formation of hybrid-type histidine kinases

    SciTech Connect

    Zhang, Weiwen; Shi, Liang

    2005-06-01

    Although most two-component signal transduction systems (TCSTS) use a simple phosphotransfer pathway from one histidine kinase (HK) to one response regulator (RR), a multiple-step phosphorelay involving a phosphotransfer scheme of His-Asp-His-Asp was discovered in recent years. Central to this multiple-step type signal transduction pathway are a hybrid-type HK, containing both an HK kinase domain and a RR receiver domain in a single protein, and a histidine-containing phosphotransfer (HPT) that can exist as either a domain in hybrid-type HKs or as a separate protein. While multiple-step phosphorelay systems predominant in eukaryotes, it has been previously suggested that they are less common in prokaryotes. In this study, we found that putative hybrid-type HKs were present in 56 out of 156 complete prokaryotic genomes, indicating that multiple-step phosphorelay systems are more common in prokaryotes than previously appreciated. Large expansions of hybrid-type HKs were observed in several types of bacterial species, including cyanobacteria, several bacteria involved in bacteria-eukaryote interaction, and metabolically versatile bacteria. Phylogenetic analysis indicated that there was no common ancestor for hybrid-type of HKs, and their origin and expansion was achieved by lateral recruitment of a receiver domain into an HK molecule and then duplication as one unit. Lateral recruitment of additional sensory domains such as PAS was also evident. HPT domains or proteins were identified in 32 of the genomes with hybrid-type HKs, however, no significant gene expansion was observed for HPTs even in genome with large number of hybrid-type HKs. In addition, the observation of fewer HPTs than hybrid-type HKs in almost all genomes studied suggests that there is no simple one-to-one relationship between them

  8. Natural selection affects multiple aspects of genetic variation at putatively neutral sites across the human genome.

    PubMed

    Lohmueller, Kirk E; Albrechtsen, Anders; Li, Yingrui; Kim, Su Yeon; Korneliussen, Thorfinn; Vinckenbosch, Nicolas; Tian, Geng; Huerta-Sanchez, Emilia; Feder, Alison F; Grarup, Niels; Jørgensen, Torben; Jiang, Tao; Witte, Daniel R; Sandbæk, Annelli; Hellmann, Ines; Lauritzen, Torsten; Hansen, Torben; Pedersen, Oluf; Wang, Jun; Nielsen, Rasmus

    2011-10-01

    A major question in evolutionary biology is how natural selection has shaped patterns of genetic variation across the human genome. Previous work has documented a reduction in genetic diversity in regions of the genome with low recombination rates. However, it is unclear whether other summaries of genetic variation, like allele frequencies, are also correlated with recombination rate and whether these correlations can be explained solely by negative selection against deleterious mutations or whether positive selection acting on favorable alleles is also required. Here we attempt to address these questions by analyzing three different genome-wide resequencing datasets from European individuals. We document several significant correlations between different genomic features. In particular, we find that average minor allele frequency and diversity are reduced in regions of low recombination and that human diversity, human-chimp divergence, and average minor allele frequency are reduced near genes. Population genetic simulations show that either positive natural selection acting on favorable mutations or negative natural selection acting against deleterious mutations can explain these correlations. However, models with strong positive selection on nonsynonymous mutations and little negative selection predict a stronger negative correlation between neutral diversity and nonsynonymous divergence than observed in the actual data, supporting the importance of negative, rather than positive, selection throughout the genome. Further, we show that the widespread presence of weakly deleterious alleles, rather than a small number of strongly positively selected mutations, is responsible for the correlation between neutral genetic diversity and recombination rate. This work suggests that natural selection has affected multiple aspects of linked neutral variation throughout the human genome and that positive selection is not required to explain these observations.

  9. Multiple Psychopharmacological Effects of the Traditional Japanese Kampo Medicine Yokukansan, and the Brain Regions it Affects

    PubMed Central

    Mizoguchi, Kazushige; Ikarashi, Yasushi

    2017-01-01

    Yokukansan (YKS), a traditional Japanese Kampo medicine, has indications for use in night crying and irritability in children, as well as neurosis and insomnia. It is currently also used for the remedy of the behavioral and psychological symptoms of dementia (BPSD), such as aggressiveness, agitation, and hallucinations. In parallel with clinical evidence, a significant amount of fundamental researches have been undertaken to clarify the neuropsychopharmacological efficacies of YKS, with approximately 70 articles, including our own, being published to date. Recently, we reviewed the neuropharmacological mechanisms of YKS, including its effects on glutamatergic, serotonergic, and dopaminergic neurotransmission, and pharmacokinetics of the ingredients responsible for the effects. This review is aimed to integrate the information regarding the psychopharmacological effects of YKS with the brain regions known to be affected, to facilitate our understanding of the clinical efficacy of YKS. In this review, we first show that YKS has several effects that act to improve symptoms that are similar to BPSDs, like aggressiveness, hallucinations, anxiety, and sleep disturbance, as well as symptoms like tardive dyskinesia and cognitive deficits. We next provide the evidence showing that YKS can interact with various brain regions, including the cerebral cortex, hippocampus, striatum, and spinal cord, dysfunctions of which are related to psychiatric symptoms, cognitive deficits, abnormal behaviors, and dysesthesia. In addition, the major active ingredients of YKS, geissoschizine methyl ether and 18β-glycyrrhetinic acid, are shown to predominantly bind to the frontal cortex and hippocampus, respectively. Our findings suggest that YKS has multiple psychopharmacological effects, and that these are probably mediated by interactions among several brain regions. In this review, we summarize the available information about the valuable effects of a multicomponent medicine YKS on complex

  10. Polymorphisms within beta-catenin encoding gene affect multiple myeloma development and treatment.

    PubMed

    Butrym, Aleksandra; Rybka, Justyna; Łacina, Piotr; Gębura, Katarzyna; Frontkiewicz, Diana; Bogunia-Kubik, Katarzyna; Mazur, Grzegorz

    2015-12-01

    Recent studies have suggested that cereblon (CRBN) is essential for the anti-myeloma (MM) activity of immunomodulatory drugs (IMiDs), such as thalidomide and lenalidomide, and that dysregulation of Wnt/β-catenin pathway may be one of possible reasons of lenalidomide resistance. This prompted us to analyze the effect of polymorphisms within the genes coding for cereblon (CRBN (rs121918368 C>T)) and β-catenin (CTNNB1 (rs4135385 A>G; rs4533622 A>C)). MM patients (n=142) and healthy individuals (n=123) were genotyped using the Light SNiP assays. The presence of the CTNNB1 (rs4533622) A allele was more frequently detected in patients presented with stage II-III disease according to International Staging System (63/82 vs. 26/44, p=0.043) and Durie-Salmon criteria (75/99 vs. 14/26, p=0.049). The CTNNB1 (rs4135385) AA homozygosity was more frequent among patients with better response to CTD, i.e., cyclophosphamide-thalidomide-dexamethasone (18/23 vs. 32/60, p=0.047). Patients carrying the CTNNB1 (rs4533622) AA genotype were better responders to the first line therapy with thalidomide containing regimens (p<0.05). No significant association was observed between the effect of lenalidomide therapy and polymorphisms studied. However, the occurrence of neutropenia during lenalidomide therapy was more frequent among the CTNNB1 (rs4135385) AA carriers (p=0.019), while the CTNNB1 (rs4533622) AA homozygosity characterized patients with high grade (3-4) neutropenia (p=0.044). No association was found for the CRBN polymorphism. These results suggest that the CTNNB1 polymorphisms may affect the clinical course and response to chemotherapy in patients with multiple myeloma.

  11. Multiple factors affect diversity and abundance of ammonia-oxidizing microorganisms in iron mine soil.

    PubMed

    Xing, Yi; Si, Yan-Xiao; Hong, Chen; Li, Yang

    2015-07-01

    Ammonia oxidation by microorganisms is a critical process in the nitrogen cycle. In this study, four soil samples collected from a desert zone in an iron-exploration area and others from farmland and planted forest soil in an iron mine surrounding area. We analyzed the abundance and diversity of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in iron-mining area near the Miyun reservoir using ammonia monooxygenase. A subunit gene (amoA) as molecular biomarker. Quantitative polymerase chain reaction was applied to explore the relationships between the abundance of AOA and AOB and soil physicochemical parameters. The results showed that AOA were more abundant than AOB and may play a more dominant role in the ammonia-oxidizing process in the whole region. PCR-denaturing gradient gel electrophoresis was used to analyze the structural changes of AOA and AOB. The results showed that AOB were much more diverse than AOA. Nitrosospira cluster three constitute the majority of AOB, and AOA were dominated by group 1.1b in the soil. Redundancy analysis was performed to explore the physicochemical parameters potentially important to AOA and AOB. Soil characteristics (i.e. water, ammonia, organic carbon, total nitrogen, available phosphorus, and soil type) were proposed to potentially contribute to the distributions of AOB, whereas Cd was also closely correlated to the distributions of AOB. The community of AOA correlated with ammonium and water contents. These results highlight the importance of multiple drivers in microbial niche formation as well as their affect on ammonia oxidizer composition, both which have significant consequences for ecosystem nitrogen functioning.

  12. Cushing's syndrome presenting as treatment-resistant bipolar affective disorder: A step in understanding endocrine etiology of mood disorders

    PubMed Central

    Ummar, I. Syed; Rajaraman, Venkateswaran; Loganathan, N.

    2015-01-01

    Cushing's syndrome (CS) is the multisystem disorder which is due to cortisol excess. It is very difficult to diagnose in early stages, especially when psychiatric manifestations are the predominant complaints. It could result in significant morbidity and mortality. We report a case of resistant bipolar affective disorder secondary to CS. Early diagnosis and treatment will lead to better functional outcome and prevention of neurocognitive side-effects of excessive cortisol. PMID:26124528

  13. 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 &…

  14. Building the Bridge between Home and School: One Rural School's Steps to Interrogate and Celebrate Multiple Literacies

    ERIC Educational Resources Information Center

    Hansen, Faith Beyer

    2009-01-01

    This paper examines one rural school's efforts to recognize and celebrate the multiple literacies of its students, by hosting a LINK Up family night that highlights the varied funds of knowledge of school, community and home. In dialogue with excerpts from Sherman Alexie's novel, "The Absolute True Diaries of a Part Time Indian," the paper…

  15. Realistic changes in seaweed biodiversity affect multiple ecosystem functions on a rocky shore.

    PubMed

    Bracken, Matthew E S; Williams, Susan L

    2013-09-01

    Given current threats to biodiversity, understanding the effects of diversity changes on the functions and services associated with intact ecosystems is of paramount importance. However, limited realism in most biodiversity studies makes it difficult to link the large and growing body of evidence for important functional consequences of biodiversity change to real-world losses of biodiversity. Here, we explored two methods of incorporating realism into biodiversity research: (1) the use of two-, five-, and eight-species assemblages that mimicked those that we observed in surveys of seaweed biodiversity patterns on a northern California (USA) rocky shore and the explicit comparison of those assemblages to random assemblages compiled from the same local species pool; and (2) the measurement of two fundamental ecosystem functions, nitrate uptake and photosynthesis, both of which contribute to growth of primary producers. Specifically, we measured nitrate uptake rates of seaweed assemblages as a function of initial nitrate concentrations and photosynthetic rates as a function of irradiance levels for both realistic and random assemblages of seaweeds. We only observed changes in ecosystem functioning along a richness gradient for realistic assemblages, and both maximum nitrate uptake rates (V(max)) and photosynthetic light use efficiency values (alpha(p) = P(max)/I(K)) were higher in realistic assemblages than in random assemblages. Furthermore, the parameter affected by changes in richness depended on the function being measured. Both V(max) and alpha(p) declined with increasing richness in nonrandom assemblages due to a combination of species identity effects (for V(max) and overyielding effects (for both V(max) and alpha(p)). In contrast, neither nitrate uptake efficiency values (alpha(N) = V(max)/K(s)), nor maximum photosynthetic rates (Pmax) changed along the gradient in seaweed species richness. Furthermore, overyielding was only evident in realistic assemblages

  16. Integration Strategy Is a Key Step in Network-Based Analysis and Dramatically Affects Network Topological Properties and Inferring Outcomes

    PubMed Central

    Jin, Nana; Wu, Deng; Gong, Yonghui; Bi, Xiaoman; Jiang, Hong; Li, Kongning; Wang, Qianghu

    2014-01-01

    An increasing number of experiments have been designed to detect intracellular and intercellular molecular interactions. Based on these molecular interactions (especially protein interactions), molecular networks have been built for using in several typical applications, such as the discovery of new disease genes and the identification of drug targets and molecular complexes. Because the data are incomplete and a considerable number of false-positive interactions exist, protein interactions from different sources are commonly integrated in network analyses to build a stable molecular network. Although various types of integration strategies are being applied in current studies, the topological properties of the networks from these different integration strategies, especially typical applications based on these network integration strategies, have not been rigorously evaluated. In this paper, systematic analyses were performed to evaluate 11 frequently used methods using two types of integration strategies: empirical and machine learning methods. The topological properties of the networks of these different integration strategies were found to significantly differ. Moreover, these networks were found to dramatically affect the outcomes of typical applications, such as disease gene predictions, drug target detections, and molecular complex identifications. The analysis presented in this paper could provide an important basis for future network-based biological researches. PMID:25243127

  17. Features of polarization decay in the transition between the low-step and multiple scattering of laser light

    NASA Astrophysics Data System (ADS)

    Zimnyakov, D. A.; Yuvchenko, S. A.; Taskina, L. A.; Alonova, M. V.; Isaeva, E. A.; Isaeva, A. A.; Ushakova, O. V.

    2016-04-01

    The effect of increase in the uncertainty of local polarization states of laser light forward scattered by random media was studied in the experiments with phantom scatterers. At macroscopic level this effect is related to decay in the degree of polarization of scattered light in the course of transition from single to multiple scattering. Gelatin layers with embedded titania particles were used as the phantom scatterers. Features of distributions of local polarization states in various polarization coordinates were considered.

  18. Multiple-step model-experiment matching allows precise definition of dynamical leg parameters in human running.

    PubMed

    Ludwig, C; Grimmer, S; Seyfarth, A; Maus, H-M

    2012-09-21

    The spring-loaded inverted pendulum (SLIP) model is a well established model for describing bouncy gaits like human running. The notion of spring-like leg behavior has led many researchers to compute the corresponding parameters, predominantly stiffness, in various experimental setups and in various ways. However, different methods yield different results, making the comparison between studies difficult. Further, a model simulation with experimentally obtained leg parameters typically results in comparatively large differences between model and experimental center of mass trajectories. Here, we pursue the opposite approach which is calculating model parameters that allow reproduction of an experimental sequence of steps. In addition, to capture energy fluctuations, an extension of the SLIP (ESLIP) is required and presented. The excellent match of the models with the experiment validates the description of human running by the SLIP with the obtained parameters which we hence call dynamical leg parameters.

  19. Regeneration of glass nanofluidic chips through a multiple-step sequential thermochemical decomposition process at high temperatures.

    PubMed

    Xu, Yan; Wu, Qian; Shimatani, Yuji; Yamaguchi, Koji

    2015-10-07

    Due to the lack of regeneration methods, the reusability of nanofluidic chips is a significant technical challenge impeding the efficient and economic promotion of both fundamental research and practical applications on nanofluidics. Herein, a simple method for the total regeneration of glass nanofluidic chips was described. The method consists of sequential thermal treatment with six well-designed steps, which correspond to four sequential thermal and thermochemical decomposition processes, namely, dehydration, high-temperature redox chemical reaction, high-temperature gasification, and cooling. The method enabled the total regeneration of typical 'dead' glass nanofluidic chips by eliminating physically clogged nanoparticles in the nanochannels, removing chemically reacted organic matter on the glass surface and regenerating permanent functional surfaces of dissimilar materials localized in the nanochannels. The method provides a technical solution to significantly improve the reusability of glass nanofluidic chips and will be useful for the promotion and acceleration of research and applications on nanofluidics.

  20. The chloroplast RNA helicase ISE2 is required for multiple chloroplast RNA processing steps in Arabidopsis thaliana.

    PubMed

    Bobik, Krzysztof; McCray, Tyra N; Ernest, Ben; Fernandez, Jessica C; Howell, Katharine A; Lane, Thomas; Staton, Margaret; Burch-Smith, Tessa M

    2017-03-27

    INCREASED SIZE EXCLUSION LIMIT2 (ISE2) is a chloroplast-localized RNA helicase that is indispensable for proper plant development. Chloroplasts in leaves with reduced ISE2 expression have previously been shown to exhibit reduced thylakoid contents and increased stromal volume, indicative of defective development. It has recently been reported that ISE2 is required for the splicing of group II introns from chloroplast transcripts. The current study extends these findings, and presents evidence for ISE2's role in multiple aspects of chloroplast RNA processing beyond group II intron splicing. Loss of ISE2 from Arabidopsis thaliana leaves resulted in defects in C-to-U RNA editing, altered accumulation of chloroplast transcripts and chloroplast-encoded proteins, and defective processing of chloroplast ribosomal RNAs. Potential ISE2 substrates were identified by RNA immunoprecipitation followed by next-generation sequencing (RIP-seq), and the diversity of RNA species identified supports ISE2's involvement in multiple aspects of chloroplast RNA metabolism. Comprehensive phylogenetic analyses revealed that ISE2 is a non-canonical Ski2-like RNA helicase that represents a separate sub-clade unique to green photosynthetic organisms, consistent with its function as an essential protein. Thus ISE2's evolutionary conservation may be explained by its numerous roles in regulating chloroplast gene expression. This article is protected by copyright. All rights reserved.

  1. Multimodal stepped care approach with acupuncture and PPAR-α agonist palmitoylethanolamide in the treatment of a patient with multiple sclerosis and central neuropathic pain.

    PubMed

    Kopsky, David J; Hesselink, Jan M Keppel

    2012-03-01

    Central neuropathic pain is a common debilitating symptom in patients with multiple sclerosis. Side effects of analgesics often limit reaching therapeutic dosages. In this case report, a 61-year-old woman with chronic central neuropathic pain due to multiple sclerosis is described. Acupuncture could only partly and temporarily reduce the pain. However, after adding the natural compound palmitoylethanolamide, a glial modulator and peroxisome proliferator-activated receptor-α agonist, pain reduction was more pronounced and the interval between acupuncture sessions could be increased. A multimodal stepped care approach is demonstrated, with acupuncture and palmitoylethanolamide both influencing non-neuronal cells, such as activated glial cells, which are key factors in the development and maintenance of neuropathic pain.

  2. Reciprocal Interactions between Multiple Myeloma Cells and Osteoprogenitor Cells Affect Bone Formation and Tumor Growth

    DTIC Science & Technology

    2015-12-01

    frequent occurrence of tumour metastases in bone (discussed later), as well as serious infections such as tuberculosis involving this tissue before...as shown in Figure 3 below. Our next step was to use a TurboRed (RFP)-containing plasmid packaged into a lentivirus to infect the cells and...Institute of Technology, Cambridge, MA 02139; dDepartment of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Harvard Medical

  3. Multiple time courses of salivary alpha-amylase and dimensions of affect in adolescence.

    PubMed

    Doane, Leah D; Van Lenten, Scott A

    2014-11-01

    Previous research has illustrated associations among daily experiences, emotions and stress-responding physiological systems. Recently, investigators have examined salivary alpha-amylase (sAA), a surrogate marker of the autonomic nervous system, and its associations with affect. The current study examined associations among affective valence, arousal and sAA across three different time courses at the momentary, daily and inter-individual level to understand varying influences of adolescents' daily emotional experiences on sAA reactivity and diurnal sAA activity. Adolescents (N=82) provided salivary samples and diary reports of affect and experiences five times a day for three consecutive days. They also completed self-report questionnaires on trait affect. Findings from multilevel growth curves demonstrated that adolescents in our sample displayed typical sAA diurnal rhythms with levels dropping 30 min after waking and then increasing across the day to a peak in the late afternoon. Within person momentary experiences of high arousal positive affect were associated with momentary sAA reactivity. Prior day experiences of high arousal negative affect were associated with a greater amylase awakening response (i.e., greater decrease) and flatter slopes the next day. Trait positive affect was also associated with flatter sAA slopes. Our findings suggest that both affective arousal and valence should be accounted for when examining differences in sAA reactivity and diurnal patterns. Further, our results indicated that emotion-physiology transactions among adolescents occur over varying time scales for salivary alpha-amylase as well as cortisol.

  4. Prognosis of the individual course of disease - steps in developing a decision support tool for Multiple Sclerosis

    PubMed Central

    Daumer, M; Neuhaus, A; Lederer, C; Scholz, M; Wolinsky, JS; Heiderhoff, M

    2007-01-01

    Background Multiple sclerosis is a chronic disease of uncertain aetiology. Variations in its disease course make it difficult to impossible to accurately determine the prognosis of individual patients. The Sylvia Lawry Centre for Multiple Sclerosis Research (SLCMSR) developed an "online analytical processing (OLAP)" tool that takes advantage of extant clinical trials data and allows one to model the near term future course of this chronic disease for an individual patient. Results For a given patient the most similar patients of the SLCMSR database are intelligently selected by a model-based matching algorithm integrated into an OLAP-tool to enable real time, web-based statistical analyses. The underlying database (last update April 2005) contains 1,059 patients derived from 30 placebo arms of controlled clinical trials. Demographic information on the entire database and the portion selected for comparison are displayed. The result of the statistical comparison is provided as a display of the course of Expanded Disability Status Scale (EDSS) for individuals in the database with regions of probable progression over time, along with their mean relapse rate. Kaplan-Meier curves for time to sustained progression in the EDSS and time to requirement of constant assistance to walk (EDSS 6) are also displayed. The software-application OLAP anticipates the input MS patient's course on the basis of baseline values and the known course of disease for similar patients who have been followed in clinical trials. Conclusion This simulation could be useful for physicians, researchers and other professionals who counsel patients on therapeutic options. The application can be modified for studying the natural history of other chronic diseases, if and when similar datasets on which the OLAP operates exist. PMID:17488517

  5. Systems Biology Approach in Chlamydomonas Reveals Connections between Copper Nutrition and Multiple Metabolic Steps[C][W][OA

    PubMed Central

    Castruita, Madeli; Casero, David; Karpowicz, Steven J.; Kropat, Janette; Vieler, Astrid; Hsieh, Scott I.; Yan, Weihong; Cokus, Shawn; Loo, Joseph A.; Benning, Christoph; Pellegrini, Matteo; Merchant, Sabeeha S.

    2011-01-01

    In this work, we query the Chlamydomonas reinhardtii copper regulon at a whole-genome level. Our RNA-Seq data simulation and analysis pipeline validated a 2-fold cutoff and 10 RPKM (reads per kilobase of mappable length per million mapped reads) (~1 mRNA per cell) to reveal 63 CRR1 targets plus another 86 copper-responsive genes. Proteomic and immunoblot analyses captured 25% of the corresponding proteins, whose abundance was also dependent on copper nutrition, validating transcriptional regulation as a major control mechanism for copper signaling in Chlamydomonas. The impact of copper deficiency on the expression of several O2-dependent enzymes included steps in lipid modification pathways. Quantitative lipid profiles indicated increased polyunsaturation of fatty acids on thylakoid membrane digalactosyldiglycerides, indicating a global impact of copper deficiency on the photosynthetic apparatus. Discovery of a putative plastid copper chaperone and a membrane protease in the thylakoid suggest a mechanism for blocking copper utilization in the chloroplast. We also found an example of copper sparing in the N assimilation pathway: the replacement of copper amine oxidase by a flavin-dependent backup enzyme. Forty percent of the targets are previously uncharacterized proteins, indicating considerable potential for new discovery in the biology of copper. PMID:21498682

  6. Poor response of initial steroid therapy for IgG4-related sclerosing cholangitis with multiple organs affected

    PubMed Central

    Liu, Wei; Chen, Weijie; He, Xiaodong; Qu, Qiang; Hong, Tao; Li, Binglu

    2017-01-01

    Abstract IgG4-related sclerosing cholangitis (IgG4-SC) is a rare biliary manifestation in which many other organs might be affected. The purpose of our study was to investigate the different clinical characteristics and initial steroid response between IgG4-SC patients with and without other organs affected. A series of patients with IgG4-SC in the period from January 2006 to December 2015 at our hospital were included. The pancreas and major salivary glands were screened, and the initial corticosteroid therapy was given. Clinical information was collected and analyzed including demographics, clinical presentation, IgG4 serology, imaging features, and treatment outcomes. The study identified 72 IgG4-SC patients, including 60 males and 12 females. The mean age was 59.8 years old. Among these IgG4-SC patients, 10 patients had only bile duct involved, 42 patients had 2 organs involved and 20 patients had multiple organs involved. In patients with multiple organs involved, more complaints were given (mean 2.9 kinds), higher serum IgG4 levels were found (23458 ± 19402.7 mg/L), and more stricture lesions of biliary tract were shown. All 72 patients exhibited a disease response within 4 to 6 weeks of starting steroids. The remission rate in the multiple lesions group was lower (60%), and the recurrence rate is higher (83.3%). The relapse-free survival was 20.0 months in the single lesion group, which is longer than that in the multiple lesions group (3.1 months, P < 0.05). The IgG4-SC patients with multiple organs affected had more complaints, higher serum IgG4 levels, and poor response to initial steroids. PMID:28328835

  7. A steroid-induced bilateral avascular necrosis of the femoral head in an underage patient affected by multiple sclerosis

    PubMed Central

    Carulli, Christian; Nistri, Lorenzo; Bracco, Laura; Giannini, Marta; Amato, Maria Pia

    2015-01-01

    Summary Patients affected by Multiple Sclerosis are often treated by pulsed intravenous corticosteroids to manage acute relapses with positive outcomes. The intravenous administration is frequently associated to avascular necrosis of several bones, particularly the femur. The present report regards a case of an underage MS patient with a bilateral ANFH secondary to pulsed administrations of steroids, managed by a conservative approach on a hip, and by a novel surgical technique on the contralateral side. PMID:26811707

  8. Characterizing multiple timescales of stream and storage zone interaction that affect solute fate and transport in streams

    USGS Publications Warehouse

    Choi, J.; Harvey, J.W.; Conklin, M.H.

    2000-01-01

    The fate of contaminants in streams and rivers is affected by exchange and biogeochemical transformation in slowly moving or stagnant flow zones that interact with rapid flow in the main channel. In a typical stream, there are multiple types of slowly moving flow zones in which exchange and transformation occur, such as stagnant or recirculating surface water as well as subsurface hyporheic zones. However, most investigators use transport models with just a single storage zone in their modeling studies, which assumes that the effects of multiple storage zones can be lumped together. Our study addressed the following question: Can a single-storage zone model reliably characterize the effects of physical retention and biogeochemical reactions in multiple storage zones? We extended an existing stream transport model with a single storage zone to include a second storage zone. With the extended model we generated 500 data sets representing transport of nonreactive and reactive solutes in stream systems that have two different types of storage zones with variable hydrologic conditions. The one storage zone model was tested by optimizing the lumped storage parameters to achieve a best fit for each of the generated data sets. Multiple storage processes were categorized as possessing I, additive; II, competitive; or III, dominant storage zone characteristics. The classification was based on the goodness of fit of generated data sets, the degree of similarity in mean retention time of the two storage zones, and the relative distributions of exchange flux and storage capacity between the two storage zones. For most cases (> 90%) the one storage zone model described either the effect of the sum of multiple storage processes (category I) or the dominant storage process (category III). Failure of the one storage zone model occurred mainly for category II, that is, when one of the storage zones had a much longer mean retention time (t(s) ratio > 5.0) and when the dominance of

  9. Lenalidomide affect expression level of cereblon protein in multiple myeloma cell line RPMI8226.

    PubMed

    Yang, D Y; Ren, J H; Guo, X N; Guo, X L; Cai, X Y; Guo, X F; Zhang, J N

    2015-10-29

    We investigated the mechanisms of action of immuno-modulatory drug (lenalidomide) on the protein expression of cereblon (CRBN) and their therapeutic targets in the multiple myeloma cell line RPMI8226. The multiple myeloma cell line RPMI8226 was cultured and treated with different concentrations of lenalidomide and bortezomib to determine the proliferation inhibition rate, apoptosis rate, and protein expression of CRBN. The results revealed that both lenalidomide and bortezomib inhibited the proliferation of RPMI8226 and promoted cell apoptosis. However, the protein expression of CRBN decreased signifi-cantly after treatment with lenalidomide, while bortezomib had no effect on the expression of CRBN. We confirmed that CRBN may be a target of lenalidomide.

  10. Stochastic analysis of multiple-passband spectral classifications systems affected by observation errors

    NASA Technical Reports Server (NTRS)

    Tsokos, C. P.

    1980-01-01

    The classification of targets viewed by a pushbroom type multiple band spectral scanner by algorithms suitable for implementation in high speed online digital circuits is considered. A class of algorithms suitable for use with a pipelined classifier is investigated through simulations based on observed data from agricultural targets. It is shown that time distribution of target types is an important determining factor in classification efficiency.

  11. Stepped MS(All) Relied Transition (SMART): An approach to rapidly determine optimal multiple reaction monitoring mass spectrometry parameters for small molecules.

    PubMed

    Ye, Hui; Zhu, Lin; Wang, Lin; Liu, Huiying; Zhang, Jun; Wu, Mengqiu; Wang, Guangji; Hao, Haiping

    2016-02-11

    Multiple reaction monitoring (MRM) is a universal approach for quantitative analysis because of its high specificity and sensitivity. Nevertheless, optimization of MRM parameters remains as a time and labor-intensive task particularly in multiplexed quantitative analysis of small molecules in complex mixtures. In this study, we have developed an approach named Stepped MS(All) Relied Transition (SMART) to predict the optimal MRM parameters of small molecules. SMART requires firstly a rapid and high-throughput analysis of samples using a Stepped MS(All) technique (sMS(All)) on a Q-TOF, which consists of serial MS(All) events acquired from low CE to gradually stepped-up CE values in a cycle. The optimal CE values can then be determined by comparing the extracted ion chromatograms for the ion pairs of interest among serial scans. The SMART-predicted parameters were found to agree well with the parameters optimized on a triple quadrupole from the same vendor using a mixture of standards. The parameters optimized on a triple quadrupole from a different vendor was also employed for comparison, and found to be linearly correlated with the SMART-predicted parameters, suggesting the potential applications of the SMART approach among different instrumental platforms. This approach was further validated by applying to simultaneous quantification of 31 herbal components in the plasma of rats treated with a herbal prescription. Because the sMS(All) acquisition can be accomplished in a single run for multiple components independent of standards, the SMART approach are expected to find its wide application in the multiplexed quantitative analysis of complex mixtures.

  12. Factors Affecting University Entrants' Performance in High-Stakes Tests: A Multiple Regression Analysis

    ERIC Educational Resources Information Center

    Uy, Chin; Manalo, Ronaldo A.; Cabauatan, Ronaldo R.

    2015-01-01

    In the Philippines, students seeking admission to a university are usually required to meet certain entrance requirements, including passing the entrance examinations with questions on IQ and English, mathematics, and science. This paper aims to determine the factors that affect the performance of entrants into business programmes in high-stakes…

  13. Peer Rated Therapeutic Talent and Affective Sensitivity: A Multiple Regression Approach.

    ERIC Educational Resources Information Center

    Jackson, Eugene

    1985-01-01

    Used peer rated measures of Warmth, Understanding and Openness to predict scores on the Kagan Affective Sensitivity Scale-E80 among 66 undergraduates who had participated in interpersonal skills training groups. Results indicated that, as an additively composite index of Therapeutic Talent, they were positively correlated with affective…

  14. Decision Aids for Multiple-Decision Disease Management as Affected by Weather Input Errors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many disease management decision support systems (DSS) rely, exclusively or in part, on weather inputs to calculate an indicator for disease hazard. Error in the weather inputs, typically due to forecasting, interpolation or estimation from off-site sources, may affect model calculations and manage...

  15. One to rule them all: A highly conserved motif in mariner transposase controls multiple steps of transposition.

    PubMed

    Bouuaert, Corentin Claeys; Tellier, Michael; Chalmers, Ronald

    2014-01-01

    The development of transposon-based genome manipulation tools can benefit greatly from understanding transposons' inherent regulatory mechanisms. The Tc1-mariner transposons, which are being widely used in biotechnological applications, are subject to a self-inhibitory mechanism whereby increasing transposase expression beyond a certain point decreases the rate of transposition. In a recent paper, Liu and Chalmers performed saturating mutagenesis on the highly conserved WVPHEL motif in the mariner-family transposase from the Hsmar1 element. Curiously, they found that the majority of all possible single mutations were hyperactive. Biochemical characterizations of the mutants revealed that the hyperactivity is due to a defect in communication between transposase subunits, which normally regulates transposition by reducing the rate of synapsis. This provides important clues for improving transposon-based tools. However, some WVPHEL mutants also showed features that would be undesirable for most biotechnological applications: they showed uncontrolled DNA cleavage activities and defects in the coordination of cleavage between the two transposon ends. The study illustrates how the knowledge of inhibitory mechanisms can help improve transposon tools but also highlights an important challenge, which is to specifically target a regulatory mechanism without affecting other important functions of the transposase.

  16. Loss of VHL in mesenchymal progenitors of the limb bud alters multiple steps of endochondral bone development

    PubMed Central

    Mangiavini, Laura; Merceron, Christophe; Araldi, Elisa; Khatri, Richa; Gerard-O'Riley, Rita; Wilson, Tremika LeShan; Rankin, Erinn B.; Giaccia, Amato J.; Schipani, Ernestina

    2014-01-01

    Adaptation to low oxygen tension (hypoxia) is a critical event during development. The transcription factors Hypoxia Inducible Factor-1α (HIF-1α) and HIF-2α are essential mediators of the homeostatic responses that allow hypoxic cells to survive and differentiate. Von Hippel Lindau protein (VHL) is the E3 ubiquitin ligase that targets HIFs to the proteasome for degradation in normoxia. We have previously demonstrated that the transcription factor HIF-1α is essential for survival and differentiation of growth plate chondrocytes, whereas HIF-2α is not necessary for fetal growth plate development. We have also shown that VHL is important for endochondral bone development, since loss of VHL in chondrocytes causes severe dwarfism. In this study, in order to expand our understanding of the role of VHL in chondrogenesis, we conditionally deleted VHL in mesenchymal progenitors of the limb bud, i.e. in cells not yet committed to the chondrocyte lineage. Deficiency of VHL in limb bud mesenchyme does not alter the timely differentiation of mesenchymal cells into chondrocytes. However, it causes structural collapse of the cartilaginous growth plate as a result of impaired proliferation, delayed terminal differentiation, and ectopic death of chondrocytes. This phenotype is associated to delayed replacement of cartilage by bone. Notably, loss of HIF-2α fully rescues the late formation of the bone marrow cavity in VHL mutant mice, though it does not affect any other detectable abnormality of the VHL mutant growth plates. Our findings demonstrate that VHL regulates bone morphogenesis as its loss considerably alters size, shape and overall development of the skeletal elements. PMID:24972088

  17. Loss of VHL in mesenchymal progenitors of the limb bud alters multiple steps of endochondral bone development.

    PubMed

    Mangiavini, Laura; Merceron, Christophe; Araldi, Elisa; Khatri, Richa; Gerard-O'Riley, Rita; Wilson, Tremika LeShan; Rankin, Erinn B; Giaccia, Amato J; Schipani, Ernestina

    2014-09-01

    Adaptation to low oxygen tension (hypoxia) is a critical event during development. The transcription factors Hypoxia Inducible Factor-1α (HIF-1α) and HIF-2α are essential mediators of the homeostatic responses that allow hypoxic cells to survive and differentiate. Von Hippel-Lindau protein (VHL) is the E3 ubiquitin ligase that targets HIFs to the proteasome for degradation in normoxia. We have previously demonstrated that the transcription factor HIF-1α is essential for survival and differentiation of growth plate chondrocytes, whereas HIF-2α is not necessary for fetal growth plate development. We have also shown that VHL is important for endochondral bone development, since loss of VHL in chondrocytes causes severe dwarfism. In this study, in order to expand our understanding of the role of VHL in chondrogenesis, we conditionally deleted VHL in mesenchymal progenitors of the limb bud, i.e. in cells not yet committed to the chondrocyte lineage. Deficiency of VHL in limb bud mesenchyme does not alter the timely differentiation of mesenchymal cells into chondrocytes. However, it causes structural collapse of the cartilaginous growth plate as a result of impaired proliferation, delayed terminal differentiation, and ectopic death of chondrocytes. This phenotype is associated to delayed replacement of cartilage by bone. Notably, loss of HIF-2α fully rescues the late formation of the bone marrow cavity in VHL mutant mice, though it does not affect any other detectable abnormality of the VHL mutant growth plates. Our findings demonstrate that VHL regulates bone morphogenesis as its loss considerably alters size, shape and overall development of the skeletal elements.

  18. How do Data Processing Choices Affect Multiple Aperture InSAR (MAI) Precision?

    NASA Astrophysics Data System (ADS)

    Bechor-Ben Dov, N.

    2015-12-01

    MAI data processing methods report different precisions, sometimes for the same data; we investigate these discrepancies here. MAI, a method to obtain phase-based along-track displacements from InSAR data, has been used for measuring volcanic, glacier, and earthquake displacements. However, different applications show vastly different precisions, ranging from a few millimeters to tens of centimeters per interferogram. While some spatial variability in precision is expected due to the InSAR phase noise dependence on terrain, some reports show different precisions for the same data. Here, I address the following questions: What is the true precision of MAI measurements? What are the MAI noise sources, and how do we mitigate them? We use data from 11 Envisat, 2 ERS, and 1 ALOS interferograms to analyze and quantify the MAI noise sources and their dependence on the method's implementation. To do that, we implement various processing steps with the JPL/Caltech InSAR data processor ROI_PAC. We find that there are several (sometimes surprising) nuances in data processing that together can reduce scatter noise by half, and other corrections that can reduce topography-related noise by up to 25 centimeters. We find that even with all the optimized data processing steps, the actual MAI errors (relative accuracy) are higher then the theoretical ones by a factor that depends on filter window size. We present an updated MAI data processor, which is capable of achieving relative accuracy and precision levels of 6 to 2 centimeters, respectively, in low to medium coherence terrains (correlation coefficient of 0.4 to 0.8), and provides error estimates that better reflect the actual relative accuracy of the measurement.

  19. The Caenorhabditis Elegans Unc-31 Gene Affects Multiple Nervous System-Controlled Functions

    PubMed Central

    Avery, L.; Bargmann, C. I.; Horvitz, H. R.

    1993-01-01

    We have devised a method for selecting Caenorhabditis elegans mutants that execute feeding motions in the absence of food. One mutation isolated in this way is an allele of the gene unc-31, first discovered by S. Brenner in 1974, because of its effects on locomotion. We find that strong unc-31 mutations cause defects in four functions controlled by the nervous system. Mutant worms are lethargic, feed constitutively, are defective in egg-laying and produce dauer larvae that fail to recover. We discuss two extreme models to explain this pleiotropy: either unc-31 affects one or a few neurons that coordinately control several different functions, or it affects many neurons that independently control different functions. PMID:8325482

  20. An investigation of multidisciplinary complex health care interventions - steps towards an integrative treatment model in the rehabilitation of People with Multiple Sclerosis

    PubMed Central

    2012-01-01

    Background The Danish Multiple Sclerosis Society initiated a large-scale bridge building and integrative treatment project to take place from 2004–2010 at a specialized Multiple Sclerosis (MS) hospital. In this project, a team of five conventional health care practitioners and five alternative practitioners was set up to work together in developing and offering individualized treatments to 200 people with MS. The purpose of this paper is to present results from the six year treatment collaboration process regarding the development of an integrative treatment model. Discussion The collaborative work towards an integrative treatment model for people with MS, involved six steps: 1) Working with an initial model 2) Unfolding the different treatment philosophies 3) Discussing the elements of the Intervention-Mechanism-Context-Outcome-scheme (the IMCO-scheme) 4) Phrasing the common assumptions for an integrative MS program theory 5) Developing the integrative MS program theory 6) Building the integrative MS treatment model. The model includes important elements of the different treatment philosophies represented in the team and thereby describes a common understanding of the complexity of the courses of treatment. Summary An integrative team of practitioners has developed an integrative model for combined treatments of People with Multiple Sclerosis. The model unites different treatment philosophies and focuses on process-oriented factors and the strengthening of the patients’ resources and competences on a physical, an emotional and a cognitive level. PMID:22524586

  1. Pain affects depression through anxiety, fatigue and sleep in Multiple Sclerosis

    PubMed Central

    Amtmann, Dagmar; Askew, Robert L.; Kim, Jiseon; Chung, Hyewon; Ehde, Dawn M.; Bombardier, Charles H.; Kraft, George H.; Jones, Salene M.; Johnson, Kurt L.

    2015-01-01

    Objective Over a quarter million individuals in the US have Multiple Sclerosis (MS). Chronic pain and depression are disproportionately high in this population. The purpose of this study was to examine the relationship between chronic pain and depression in MS and to examine potentially meditational effects of anxiety, fatigue and sleep. Methods Cross-sectional data from self-reported instruments measuring multiple symptoms and quality of life indicators were used in this study. Structural equation modeling (SEM) was utilized to model direct and indirect effects of pain on depression in a sample of 1245 community dwelling individuals with MS. Pain interference, depression, fatigue and sleep disturbance were modeled as latent variables with 2 to 3 indicators each. The model controlled for age, sex, disability status (EDSS) and social support. Results A model with indirect effects of pain on depression had adequate fit and accounted for nearly 80% of the variance in depression. The effects of chronic pain on depression were almost completely mediated by fatigue, anxiety, and sleep disturbance. Higher pain was associated with greater fatigue, anxiety, and sleep disturbance, which in turn were associated with higher levels of depression. The largest mediating effect was through fatigue. Additional analyses excluded items with common content and suggested that the meditational effects observed were not attributable to content overlap across scales. Conclusions Individuals living with MS who report high levels of chronic pain and depressive symptoms may benefit from treatment approaches that can address sleep, fatigue, and anxiety. PMID:25602361

  2. Shade affects responses to drought and flooding - acclimation to multiple stresses in bittersweet (Solanum dulcamara L.).

    PubMed

    Visser, E J W; Zhang, Q; De Gruyter, F; Martens, S; Huber, H

    2016-01-01

    Plants exposed to environmental stress often respond by a change in their phenotypic traits. These changes in trait expression may alleviate the negative effect of such stress factors. However, if multiple stresses are present, responses are likely to be less predictable and hence do not necessarily correlate to plant performance. This study tested if this expectation was true, by subjecting Solanum dulcamara plants to various simultaneous stress factors. Plants were grown in well-watered conditions, drought or flooding, and exposed to either full light or shade for 4 weeks. Shoot and root biomass, stem morphological parameters, such as height, number of nodes and length of stem internodes, and leaf traits like length, specific leaf area, chlorophyll content and stomatal conductance were determined. Both variation in light and in water availability typically caused slower growth, and resulted in distinct phenotypic changes in stem, leaf and root traits. However, effects of stresses on the expression of traits were not always additive. Instead, some combined stress responses (e.g. leaf size) appeared to be limited by physical or physiological constraints, whereas other responses were opposite to each other (e.g. root:shoot ratio), resulting in an intermediate phenotype in the combined stress treatment. These data suggest that in natural conditions, where combined stress factors are likely to be present, the optimal phenotype may not necessarily be expressed. Responses of plants to multiple stress factors may therefore not be associated with immediate advantages in terms of increased performance.

  3. Hemoglobinopathic Erythrocytes Affect the Intraerythrocytic Multiplication of Plasmodium falciparum In Vitro

    PubMed Central

    Glushakova, Svetlana; Balaban, Amanda; McQueen, Philip G.; Coutinho, Rosane; Miller, Jeffery L.; Nossal, Ralph; Fairhurst, Rick M.; Zimmerberg, Joshua

    2014-01-01

    Background. The mechanisms by which α-thalassemia and sickle cell traits confer protection from severe Plasmodium falciparum malaria are not yet fully elucidated. We hypothesized that hemoglobinopathic erythrocytes reduce the intraerythrocytic multiplication of P. falciparum, potentially delaying the development of life-threatening parasite densities until parasite clearing immunity is achieved. Methods. We developed a novel in vitro assay to quantify the number of merozoites released from an individual schizont, termed the “intraerythrocytic multiplication factor” (IMF). Results. P. falciparum (3D7 line) schizonts produce variable numbers of merozoites in all erythrocyte types tested, with median IMFs of 27, 27, 29, 23, and 23 in control, HbAS, HbSS, and α- and β-thalassemia trait erythrocytes, respectively. IMF correlated strongly (r2 = 0.97; P < .001) with mean corpuscular hemoglobin concentration, and varied significantly with mean corpuscular volume and hemoglobin content. Reduction of IMFs in thalassemia trait erythrocytes was confirmed using clinical parasite isolates with different IMFs. Mathematical modeling of the effect of IMF on malaria progression indicates that the lower IMF in thalassemia trait erythrocytes limits parasite density and anemia severity over the first 2 weeks of parasite replication. Conclusions. P. falciparum IMF, a parasite heritable virulence trait, correlates with erythrocyte indices and is reduced in thalassemia trait erythrocytes. Parasite IMF should be examined in other low-indices erythrocytes. PMID:24688070

  4. Arteriolosclerosis that affects multiple brain regions is linked to hippocampal sclerosis of ageing.

    PubMed

    Neltner, Janna H; Abner, Erin L; Baker, Steven; Schmitt, Frederick A; Kryscio, Richard J; Jicha, Gregory A; Smith, Charles D; Hammack, Eleanor; Kukull, Walter A; Brenowitz, Willa D; Van Eldik, Linda J; Nelson, Peter T

    2014-01-01

    Hippocampal sclerosis of ageing is a prevalent brain disease that afflicts older persons and has been linked with cerebrovascular pathology. Arteriolosclerosis is a subtype of cerebrovascular pathology characterized by concentrically thickened arterioles. Here we report data from multiple large autopsy series (University of Kentucky Alzheimer's Disease Centre, Nun Study, and National Alzheimer's Coordinating Centre) showing a specific association between hippocampal sclerosis of ageing pathology and arteriolosclerosis. The present analyses incorporate 226 cases of autopsy-proven hippocampal sclerosis of ageing and 1792 controls. Case-control comparisons were performed including digital pathological assessments for detailed analyses of blood vessel morphology. We found no evidence of associations between hippocampal sclerosis of ageing pathology and lacunar infarcts, large infarcts, Circle of Willis atherosclerosis, or cerebral amyloid angiopathy. Individuals with hippocampal sclerosis of ageing pathology did not show increased rates of clinically documented hypertension, diabetes, or other cardiac risk factors. The correlation between arteriolosclerosis and hippocampal sclerosis of ageing pathology was strong in multiple brain regions outside of the hippocampus. For example, the presence of arteriolosclerosis in the frontal cortex (Brodmann area 9) was strongly associated with hippocampal sclerosis of ageing pathology (P < 0.001). This enables informative evaluation of anatomical regions outside of the hippocampus. To assess the morphology of brain microvasculature far more rigorously than what is possible using semi-quantitative pathological scoring, we applied digital pathological (Aperio ScanScope) methods on a subsample of frontal cortex sections from hippocampal sclerosis of ageing (n = 15) and control (n = 42) cases. Following technical studies to optimize immunostaining methods for small blood vessel visualization, our analyses focused on sections

  5. Self-reported trait mindfulness and affective reactivity: a motivational approach using multiple psychophysiological measures.

    PubMed

    Cosme, Danielle; Wiens, Stefan

    2015-01-01

    As a form of attention, mindfulness is qualitatively receptive and non-reactive, and is thought to facilitate adaptive emotional responding. One suggested mechanism is that mindfulness facilitates disengagement from an affective stimulus and thereby decreases affective reactivity. However, mindfulness has been conceptualized as a state, intervention, and trait. Because evidence is mixed as to whether self-reported trait mindfulness decreases affective reactivity, we used a multi-method approach to study the relationship between individual differences in self-reported trait mindfulness and electrocortical, electrodermal, electromyographic, and self-reported responses to emotional pictures. Specifically, while participants (N = 51) passively viewed pleasant, neutral, and unpleasant IAPS pictures, we recorded high-density (128 channels) electrocortical, electrodermal, and electromyographic data to the pictures as well as to acoustic startle probes presented during the pictures. Afterwards, participants rated their subjective valence and arousal while viewing the pictures again. If trait mindfulness spontaneously reduces general emotional reactivity, then for individuals reporting high rather than low mindfulness, response differences between emotional and neutral pictures would show relatively decreased early posterior negativity (EPN) and late positive potential (LPP) amplitudes, decreased skin conductance responses, and decreased subjective ratings for valence and arousal. High mindfulness would also be associated with decreased emotional modulation of startle eyeblink and P3 amplitudes. Although results showed clear effects of emotion on the dependent measures, in general, mindfulness did not moderate these effects. For most measures, effect sizes were small with rather narrow confidence intervals. These data do not support the hypothesis that individual differences in self-reported trait mindfulness are related to spontaneous emotional responses during picture

  6. Self-Reported Trait Mindfulness and Affective Reactivity: A Motivational Approach Using Multiple Psychophysiological Measures

    PubMed Central

    Cosme, Danielle; Wiens, Stefan

    2015-01-01

    As a form of attention, mindfulness is qualitatively receptive and non-reactive, and is thought to facilitate adaptive emotional responding. One suggested mechanism is that mindfulness facilitates disengagement from an affective stimulus and thereby decreases affective reactivity. However, mindfulness has been conceptualized as a state, intervention, and trait. Because evidence is mixed as to whether self-reported trait mindfulness decreases affective reactivity, we used a multi-method approach to study the relationship between individual differences in self-reported trait mindfulness and electrocortical, electrodermal, electromyographic, and self-reported responses to emotional pictures. Specifically, while participants (N = 51) passively viewed pleasant, neutral, and unpleasant IAPS pictures, we recorded high-density (128 channels) electrocortical, electrodermal, and electromyographic data to the pictures as well as to acoustic startle probes presented during the pictures. Afterwards, participants rated their subjective valence and arousal while viewing the pictures again. If trait mindfulness spontaneously reduces general emotional reactivity, then for individuals reporting high rather than low mindfulness, response differences between emotional and neutral pictures would show relatively decreased early posterior negativity (EPN) and late positive potential (LPP) amplitudes, decreased skin conductance responses, and decreased subjective ratings for valence and arousal. High mindfulness would also be associated with decreased emotional modulation of startle eyeblink and P3 amplitudes. Although results showed clear effects of emotion on the dependent measures, in general, mindfulness did not moderate these effects. For most measures, effect sizes were small with rather narrow confidence intervals. These data do not support the hypothesis that individual differences in self-reported trait mindfulness are related to spontaneous emotional responses during picture

  7. Security: Step by Step

    ERIC Educational Resources Information Center

    Svetcov, Eric

    2005-01-01

    This article provides a list of the essential steps to keeping a school's or district's network safe and sound. It describes how to establish a security architecture and approach that will continually evolve as the threat environment changes over time. The article discusses the methodology for implementing this approach and then discusses the…

  8. Do multiple fires interact to affect vegetation structure in temperate eucalypt forests?

    PubMed

    Haslem, Angie; Leonard, Steve W J; Bruce, Matthew J; Christie, Fiona; Holland, Greg J; Kelly, Luke T; MacHunter, Josephine; Bennett, Andrew F; Clarke, Michael F; York, Alan

    2016-12-01

    Fire plays an important role in structuring vegetation in fire-prone regions worldwide. Progress has been made towards documenting the effects of individual fire events and fire regimes on vegetation structure; less is known of how different fire history attributes (e.g., time since fire, fire frequency) interact to affect vegetation. Using the temperate eucalypt foothill forests of southeastern Australia as a case study system, we examine two hypotheses about such interactions: (1) post-fire vegetation succession (e.g., time-since-fire effects) is influenced by other fire regime attributes and (2) the severity of the most recent fire overrides the effect of preceding fires on vegetation structure. Empirical data on vegetation structure were collected from 540 sites distributed across central and eastern Victoria, Australia. Linear mixed models were used to examine these hypotheses and determine the relative influence of fire and environmental attributes on vegetation structure. Fire history measures, particularly time since fire, affected several vegetation attributes including ground and canopy strata; others such as low and sub-canopy vegetation were more strongly influenced by environmental characteristics like rainfall. There was little support for the hypothesis that post-fire succession is influenced by fire history attributes other than time since fire; only canopy regeneration was influenced by another variable (fire type, representing severity). Our capacity to detect an overriding effect of the severity of the most recent fire was limited by a consistently weak effect of preceding fires on vegetation structure. Overall, results suggest the primary way that fire affects vegetation structure in foothill forests is via attributes of the most recent fire, both its severity and time since its occurrence; other attributes of fire regimes (e.g., fire interval, frequency) have less influence. The strong effect of environmental drivers, such as rainfall and

  9. Decision aids for multiple-decision disease management as affected by weather input errors.

    PubMed

    Pfender, W F; Gent, D H; Mahaffee, W F; Coop, L B; Fox, A D

    2011-06-01

    Many disease management decision support systems (DSSs) rely, exclusively or in part, on weather inputs to calculate an indicator for disease hazard. Error in the weather inputs, typically due to forecasting, interpolation, or estimation from off-site sources, may affect model calculations and management decision recommendations. The extent to which errors in weather inputs affect the quality of the final management outcome depends on a number of aspects of the disease management context, including whether management consists of a single dichotomous decision, or of a multi-decision process extending over the cropping season(s). Decision aids for multi-decision disease management typically are based on simple or complex algorithms of weather data which may be accumulated over several days or weeks. It is difficult to quantify accuracy of multi-decision DSSs due to temporally overlapping disease events, existence of more than one solution to optimizing the outcome, opportunities to take later recourse to modify earlier decisions, and the ongoing, complex decision process in which the DSS is only one component. One approach to assessing importance of weather input errors is to conduct an error analysis in which the DSS outcome from high-quality weather data is compared with that from weather data with various levels of bias and/or variance from the original data. We illustrate this analytical approach for two types of DSS, an infection risk index for hop powdery mildew and a simulation model for grass stem rust. Further exploration of analysis methods is needed to address problems associated with assessing uncertainty in multi-decision DSSs.

  10. Multiple signals and male spacing affect female preference at cocktail parties in treefrogs

    PubMed Central

    Richardson, Christina; Lengagne, Thierry

    2010-01-01

    Effective acoustic communication in the face of intense conspecific background noise constitutes a constant sensory challenge in chorusing and colonial species. An evolutionary approach suggests that behavioural and environmental constraints in these species should have shaped signal design and signalling behaviour to enable communication in noisy conditions. This could be attained both through the use of multicomponent signals and through short-term adjustments in the spatial separation of calling males. We investigated these two hypotheses in a chorusing anuran, the hylid Hyla arborea, through a series of phonotaxis experiments conducted within a six-speaker arena in a high background noise situation, by presenting females with male calls containing either single or multiple attractive call components, and by modifying distances between speakers. We found that female ability to discriminate attractive calls increased when several attractive call components were available, providing novel evidence that the use of multicomponent signals enhances communication in complex acoustic conditions. Signal discrimination in females also improved with speaker separation, demonstrating that within natural choruses, spatial unmasking conditioned by male density and spatial separation probably improves female discrimination of competing males. Implications of these results for the accuracy of mate choice within choruses are discussed. PMID:20018785

  11. How multiple social networks affect user awareness: The information diffusion process in multiplex networks

    NASA Astrophysics Data System (ADS)

    Li, Weihua; Tang, Shaoting; Fang, Wenyi; Guo, Quantong; Zhang, Xiao; Zheng, Zhiming

    2015-10-01

    The information diffusion process in single complex networks has been extensively studied, especially for modeling the spreading activities in online social networks. However, individuals usually use multiple social networks at the same time, and can share the information they have learned from one social network to another. This phenomenon gives rise to a new diffusion process on multiplex networks with more than one network layer. In this paper we account for this multiplex network spreading by proposing a model of information diffusion in two-layer multiplex networks. We develop a theoretical framework using bond percolation and cascading failure to describe the intralayer and interlayer diffusion. This allows us to obtain analytical solutions for the fraction of informed individuals as a function of transmissibility T and the interlayer transmission rate θ . Simulation results show that interaction between layers can greatly enhance the information diffusion process. And explosive diffusion can occur even if the transmissibility of the focal layer is under the critical threshold, due to interlayer transmission.

  12. How multiple social networks affect user awareness: The information diffusion process in multiplex networks.

    PubMed

    Li, Weihua; Tang, Shaoting; Fang, Wenyi; Guo, Quantong; Zhang, Xiao; Zheng, Zhiming

    2015-10-01

    The information diffusion process in single complex networks has been extensively studied, especially for modeling the spreading activities in online social networks. However, individuals usually use multiple social networks at the same time, and can share the information they have learned from one social network to another. This phenomenon gives rise to a new diffusion process on multiplex networks with more than one network layer. In this paper we account for this multiplex network spreading by proposing a model of information diffusion in two-layer multiplex networks. We develop a theoretical framework using bond percolation and cascading failure to describe the intralayer and interlayer diffusion. This allows us to obtain analytical solutions for the fraction of informed individuals as a function of transmissibility T and the interlayer transmission rate θ. Simulation results show that interaction between layers can greatly enhance the information diffusion process. And explosive diffusion can occur even if the transmissibility of the focal layer is under the critical threshold, due to interlayer transmission.

  13. Pep3p/Pep5p complex: a putative docking factor at multiple steps of vesicular transport to the vacuole of Saccharomyces cerevisiae.

    PubMed Central

    Srivastava, A; Woolford, C A; Jones, E W

    2000-01-01

    Pep3p and Pep5p are known to be necessary for trafficking of hydrolase precursors to the vacuole and for vacuolar biogenesis. These proteins are present in a hetero-oligomeric complex that mediates transport at the vacuolar membrane. PEP5 interacts genetically with VPS8, implicating Pep5p in the earlier Golgi to endosome step and/or in recycling from the endosome to the Golgi. To understand further the cellular roles of Pep3p and Pep5p, we isolated and characterized a set of pep3 conditional mutants. Characterization of mutants revealed that pep3(ts) mutants are defective in the endosomal and nonendosomal Golgi to vacuole transport pathways, in the cytoplasm to vacuole targeting pathway, in recycling from the endosome back to the late Golgi, and in endocytosis. PEP3 interacts genetically with two members of the endosomal SNARE complex, PEP12 (t-SNARE) and PEP7 (homologue of mammalian EEA1); Pep3p and Pep5p associate physically with Pep7p as revealed by two-hybrid analysis. Our results suggest that a core Pep3p/Pep5p complex promotes vesicular docking/fusion reactions in conjunction with SNARE proteins at multiple steps in transport routes to the vacuole. We propose that this complex may be responsible for tethering transport vesicles on target membranes. PMID:10978279

  14. An olfactory-limbic model of multiple chemical sensitivity syndrome: Possible relationships to kindling and affective spectrum disorders

    SciTech Connect

    Bell, I.R.; Miller, C.S.; Schwartz, G.E. )

    1992-08-01

    This paper reviews the clinical and experimental literature on patients with multiple adverse responses to chemicals (Multiple Chemical Sensitivity Syndrome-MCS) and develops a model for MCS based on olfactory-limbic system dysfunction that overlaps in part with Post's kindling model for affective disorders. MCS encompasses a broad range of chronic polysymptomatic conditions and complaints whose triggers are reported to include low levels of common indoor and outdoor environmental chemicals, such as pesticides and solvents. Other investigators have found evidence of increased prevalence of depression, anxiety, and somatization disorders in MCS patients and have concluded that their psychiatric conditions account for the clinical picture. However, none of these studies has presented any data on the effects of chemicals on symptoms or on objective measures of nervous system function. Synthesis of the MCS literature with large bodies of research in neurotoxicology, occupational medicine, and biological psychiatry, suggests that the phenomenology of MCS patients overlaps that of affective spectrum disorders and that both involve dysfunction of the limbic pathways. Animal studies demonstrate that intermittent repeated low level environmental chemical exposures, including pesticides, cause limbic kindling. Kindling (full or partial) is one central nervous system mechanism that could amplify reactivity to low levels of inhaled and ingested chemicals and initiate persistent affective, cognitive, and somatic symptomatology in both occupational and nonoccupational settings. As in animal studies, inescapable and novel stressors could cross-sensitize with chemical exposures in some individuals to generate adverse responses on a neurochemical basis. The olfactory-limbic model raises testable neurobiological hypotheses that could increase understanding of the multifactorial etiology of MCS and of certain overlapping affective spectrum disorders. 170 refs.

  15. Cereblon and IRF4 Variants Affect Risk and Response to Treatment in Multiple Myeloma.

    PubMed

    Butrym, Aleksandra; Łacina, Piotr; Rybka, Justyna; Chaszczewska-Markowska, Monika; Mazur, Grzegorz; Bogunia-Kubik, Katarzyna

    2017-01-12

    Multiple myeloma (MM) is a plasma-cell malignancy derived from an early precursor of the B-cell lineage characterised by bone-marrow infiltration, lytic bone lesions, and the presence of a monoclonal protein in serum and/or urine. Interferon regulatory factor 4 (IRF4) is a critical transcriptional regulator in B-cell development and function that is required during immune response for lymphocyte activation and the generation of immunoglobulin-secreting plasma cells. Immunomodulatory drugs, derivatives of thalidomide, are commonly used in therapy against MM. They are known to target a protein called cereblon (CRBN); however, the exact mechanism remains unknown. The present study aimed to assess the association of two (rs12203592 and rs872071) polymorphisms within the IRF4 gene and two (rs711613 and rs1045433) in the CRBN gene with MM susceptibility, progression, and response to treatment. For this purpose, 144 MM patients and 126 healthy individuals were genotyped for the IRF4 and CRBN alleles. The presence of the IRF4 (rs872071) G allele was more frequently detected in patients than healthy individuals (OR 1.78; P = 0.034), and this relationship was especially pronounced in women (OR 2.83; P = 0.012). The CRBN (rs711613) A allele-carriers were better responders to the treatment (P = 0.012), in particular to thalidomide including therapy (P = 0.023). These results underline the prognostic significance of the IRF4 and CRBN polymorphisms in patients with MM.

  16. Developmental methoxychlor exposure affects multiple reproductive parameters and ovarian folliculogenesis and gene expression in adult rats

    SciTech Connect

    Armenti, AnnMarie E.; Zama, Aparna Mahakali; Passantino, Lisa; Uzumcu, Mehmet

    2008-12-01

    Methoxychlor (MXC) is an organochlorine pesticide with estrogenic, anti-estrogenic, and anti-androgenic properties. To investigate whether transient developmental exposure to MXC could cause adult ovarian dysfunction, we exposed Fischer rats to 20 {mu}g/kg/day (low dose; environmentally relevant dose) or 100 mg/kg/day (high dose) MXC between 19 days post coitum and postnatal day 7. Multiple reproductive parameters, serum hormone levels, and ovarian morphology and molecular markers were examined from prepubertal through adult stages. High dose MXC accelerated pubertal onset and first estrus, reduced litter size, and increased irregular cyclicity (P < 0.05). MXC reduced superovulatory response to exogenous gonadotropins in prepubertal females (P < 0.05). Rats exposed to high dose MXC had increasing irregular estrous cyclicity beginning at 4 months of age, with all animals showing abnormal cycles by 6 months. High dose MXC reduced serum progesterone, but increased luteinizing hormone (LH). Follicular composition analysis revealed an increase in the percentage of preantral and early antral follicles and a reduction in the percentage of corpora lutea in high dose MXC-treated ovaries (P < 0.05). Immunohistochemical staining and quantification of the staining intensity showed that estrogen receptor {beta} was reduced by high dose MXC while anti-Mullerian hormone was upregulated by both low- and high dose MXC in preantral and early antral follicles (P < 0.05). High dose MXC significantly reduced LH receptor expression in large antral follicles (P < 0.01), and down-regulated cytochrome P450 side-chain cleavage. These results demonstrated that developmental MXC exposure results in reduced ovulation and fertility and premature aging, possibly by altering ovarian gene expression and folliculogenesis.

  17. Multiple factors affect a population of Agassiz's desert tortoise (Gopherus agassizii) in the Northwestern Mojave Desert

    USGS Publications Warehouse

    Berry, Kristin H.; Yee, Julie L.; Coble, Ashley A.; Perry, William M.; Shields, Timothy A.

    2013-01-01

    Numerous factors have contributed to declines in populations of the federally threatened Agassiz's Desert Tortoise (Gopherus agassizii) and continue to limit recovery. In 2010, we surveyed a low-density population on a military test facility in the northwestern Mojave Desert of California, USA, to evaluate population status and identify potential factors contributing to distribution and low densities. Estimated densities of live tortoises ranged spatially from 1.2/km2 to 15.1/km2. Although only one death of a breeding-age tortoise was recorded for the 4-yr period prior to the survey, remains of 16 juvenile and immature tortoises were found, and most showed signs of predation by Common Ravens (Corvus corax) and mammals. Predation may have limited recruitment of young tortoises into the adult size classes. To evaluate the relative importance of different types of impacts to tortoises, we developed predictive models for spatially explicit densities of tortoise sign and live tortoises using topography (i.e., slope), predators (Common Raven, signs of mammalian predators), and anthropogenic impacts (distances from paved road and denuded areas, density of ordnance fragments) as covariates. Models suggest that densities of tortoise sign increased with slope and signs of mammalian predators and decreased with Common Ravens, while also varying based on interaction effects involving these predictors as well as distances from paved roads, denuded areas, and ordnance. Similarly, densities of live tortoises varied by interaction effects among distances to denuded areas and paved roads, density of ordnance fragments, and slope. Thus multiple factors predict the densities and distribution of this population.

  18. Altered precipitation regime affects the function and composition of soil microbial communities on multiple time scales.

    PubMed

    Zeglin, L H; Bottomley, P J; Jumpponen, A; Rice, C W; Arango, M; Lindsley, A; McGowan, A; Mfombep, P; Myrold, D D

    2013-10-01

    Climate change models predict that future precipitation patterns will entail lower-frequency but larger rainfall events, increasing the duration of dry soil conditions. Resulting shifts in microbial C cycling activity could affect soil C storage. Further, microbial response to rainfall events may be constrained by the physiological or nutrient limitation stress of extended drought periods; thus seasonal or multiannual precipitation regimes may influence microbial activity following soil wet-up. We quantified rainfall-driven dynamics of microbial processes that affect soil C loss and retention, and microbial community composition, in soils from a long-term (14-year) field experiment contrasting "Ambient" and "Altered" (extended intervals between rainfalls) precipitation regimes. We collected soil before, the day following, and five days following 2.5-cm rainfall events during both moist and dry periods (June and September 2011; soil water potential = -0.01 and -0.83 MPa, respectively), and measured microbial respiration, microbial biomass, organic matter decomposition potential (extracellular enzyme activities), and microbial community composition (phospholipid fatty acids). The equivalent rainfall events caused equivalent microbial respiration responses in both treatments. In contrast, microbial biomass was higher and increased after rainfall in the Altered treatment soils only, thus microbial C use efficiency (CUE) was higher in Altered than Ambient treatments (0.70 +/- 0.03 > 0.46 +/- 0.10). CUE was also higher in dry (September) soils. C-acquiring enzyme activities (beta-glucosidase, cellobiohydrolase, and phenol oxidase) increased after rainfall in moist (June), but not dry (September) soils. Both microbial biomass C:N ratios and fungal:bacterial ratios were higher at lower soil water contents, suggesting a functional and/or population-level shift in the microbiota at low soil water contents, and microbial community composition also differed following wet

  19. Mobile phones affect multiple sperm quality traits: a meta-analysis

    PubMed Central

    Dama, Madhukar Shivajirao

    2013-01-01

    As mobile phone usage is growing rapidly, there is a need for a comprehensive analysis of the literature to inform scientific debates about the adverse effects of mobile phone radiation on sperm quality traits. Therefore, we conducted a meta-analysis of the eligible published research studies on human males of reproductive age. Eleven studies were eligible for this analysis. Based on the meta-analysis, mobile phone use was significantly associated with deterioration in semen quality (Hedges’s g = -0.547; 95% CI: -0.713, -0.382; p < 0.001). The traits particularly affected adversely were sperm concentration, sperm morphology, sperm motility, proportion of non-progressive motile sperm (%), proportion of slow progressive motile sperm (%), and sperm viability. Direct exposure of spermatozoa to mobile phone radiation with in vitro study designs also significantly deteriorated the sperm quality (Hedges’s g = -2.233; 95% CI: -2.758, -1.708; p < 0.001), by reducing straight line velocity, fast progressive motility, Hypo-osmotic swelling (HOS) test score, major axis (µm), minor axis (µm), total sperm motility, perimeter (µm), area (µm 2), average path velocity, curvilinear velocity, motile spermatozoa, and  acrosome reacted spermatozoa (%). The strength of evidence for the different outcomes varied from very low to very high. The analysis shows that mobile phone use is possibly associated with a number of deleterious effects on the spermatozoa. PMID:24327874

  20. Mutations affecting a putative MutLα endonuclease motif impact multiple mismatch repair functions

    PubMed Central

    Erdeniz, Naz; Nguyen, Megan; Deschênes, Suzanne M.; Liskay, R. Michael

    2008-01-01

    Mutations in DNA mismatch repair (MMR) lead to increased mutation rates and higher recombination between similar, but not identical sequences, as well as resistance to certain DNA methylating agents. Recently, a component of human MMR machinery, MutLα, has been shown to display a latent endonuclease activity. The endonuclease active site appears to include a conserved motif, DQHA(X)2E(X)4E, within the COOH-terminus of human PMS2. Substitution of the glutamic acid residue (E705) abolished the endonuclease activity and mismatch-dependent excision in vitro. Previously, we showed that the PMS2-E705K mutation and the corresponding mutation in Saccharomyces cerevisiae were both recessive loss of function alleles for mutation avoidance in vivo. Here, we show that mutations impacting this endonuclease motif also significantly affect MMR-dependent suppression of homeologous recombination in yeast and responses to Sn1-type methylating agents in both yeast and mammalian cells. Thus, our in vivo results suggest that the endonuclease activity of MutLα is important not only in MMR-dependent mutation avoidance but also for recombination and damage response functions. PMID:17567544

  1. Multiple Trans-Sensing Interactions Affect Meiotically Heritable Epigenetic States at the Maize pl1 Locus

    PubMed Central

    Gross, Stephen M.; Hollick, Jay B.

    2007-01-01

    Interactions between specific maize purple plant1 (pl1) alleles result in heritable changes of gene regulation that are manifested as differences in anthocyanin pigmentation. Transcriptionally repressed states of Pl1-Rhoades alleles (termed Pl′) are remarkably stable and invariably facilitate heritable changes of highly expressed states (termed Pl-Rh) in Pl′/Pl-Rh plants. However, Pl′ can revert to Pl-Rh when hemizygous, when heterozygous with pl1 alleles other than Pl1-Rhoades, or in the absence of trans-acting factors required to maintain repressed states. Cis-linked features of Pl1-Rhoades responsible for these trans-sensing behaviors remain unknown. Here, genetic tests of a pl1 allelic series identify two potentially separate cis-linked features: one facilitating repression of Pl-Rh and another stabilizing Pl′ in trans. Neither function is affected in ethyl-methanesulfonate-induced Pl1-Rhoades derivatives that produce truncated PL1 peptides, indicating that PL1 is unlikely to mediate trans interactions. Both functions, however, are impaired in a spontaneous Pl1-Rhoades derivative that fails to produce detectable pl1 RNA. Pl′-like states can also repress expression of a pl1-W22 allele, but this repression is not meiotically heritable. As the Pl′ state is not associated with unique small RNA species representing the pl1-coding region, the available data suggest that interactions between elements required for transcription underlie Pl1-Rhoades epigenetic behaviors. PMID:17435245

  2. Presentation and validation of the multiple sclerosis depression rating scale: a test specifically devised to investigate affective disorders in multiple sclerosis patients.

    PubMed

    Quaranta, Davide; Marra, Camillo; Zinno, Massimiliano; Patanella, Agata Katia; Messina, Maria Josè; Piccininni, Chiara; Batocchi, Anna Paola; Gainotti, Guido

    2012-01-01

    Accurate diagnosis of depression in patients affected by MS is important, as it may be a cause of reduced quality of life and increased suicide risk. We present a new scale, the Multiple Sclerosis Depression Rating Scale (MSDRS), and assess its diagnostic accuracy in comparison to the Beck Depression Inventory (BDI). A total of 94 MS participants were classified as non-depressed (N = 44) or affected by mood disorder associated to MS with depressive manifestations (MSD-MDDM; N = 37) or with a major depression-like episode (MSD-MDL; N = 13). Each participant underwent a psychiatric interview, MSDRS, and BDI; diagnostic accuracy was evaluated using area under the ROC curve (AROC). The diagnostic accuracy of MSDRS and BDI was comparable when diagnosing both MSD-MDDM and MSD-MDL (AROC respectively 0.8998 and 0.8659); the MSDRS showed higher accuracy for the diagnosis of MSD-MDL (AROC respectively 0.9278 and 0.8314; p = .038). The MSDRS may be a reliable tool for the diagnosis of depression in MS.

  3. Potential electrostatic interactions in multiple regions affect human metapneumovirus F-mediated membrane fusion.

    PubMed

    Chang, Andres; Hackett, Brent A; Winter, Christine C; Buchholz, Ursula J; Dutch, Rebecca Ellis

    2012-09-01

    The recently identified human metapneumovirus (HMPV) is a worldwide respiratory virus affecting all age groups and causing pneumonia and bronchiolitis in severe cases. Despite its clinical significance, no specific antiviral agents have been approved for treatment of HMPV infection. Unlike the case for most paramyxoviruses, the fusion proteins (F) of a number of strains, including the clinical isolate CAN97-83, can be triggered by low pH. We recently reported that residue H435 in the HRB linker domain acts as a pH sensor for HMPV CAN97-83 F, likely through electrostatic repulsion forces between a protonated H435 and its surrounding basic residues, K295, R396, and K438, at low pH. Through site-directed mutagenesis, we demonstrated that a positive charge at position 435 is required but not sufficient for F-mediated membrane fusion. Arginine or lysine substitution at position 435 resulted in a hyperfusogenic F protein, while replacement with aspartate or glutamate abolished fusion activity. Studies with recombinant viruses carrying mutations in this region confirmed its importance. Furthermore, a second region within the F(2) domain identified as being rich in charged residues was found to modulate fusion activity of HMPV F. Loss of charge at residues E51, D54, and E56 altered local folding and overall stability of the F protein, with dramatic consequences for fusion activity. As a whole, these studies implicate charged residues and potential electrostatic interactions in function, pH sensing, and overall stability of HMPV F.

  4. Insights into hemolytic uremic syndrome: segregation of three independent predisposition factors in a large, multiple affected pedigree.

    PubMed

    Esparza-Gordillo, Jorge; Jorge, Elena Goicoechea de; Garrido, Cynthia Abarrategui; Carreras, Luis; López-Trascasa, Margarita; Sánchez-Corral, Pilar; de Córdoba, Santiago Rodríguez

    2006-04-01

    Mutations in the complement regulators factor H, membrane cofactor protein (MCP), and factor I are associated with atypical hemolytic uremic syndrome (aHUS, MIM 235400), suggesting that the disease develops as a consequence of the inefficient protection of the renal endothelium from damage by the complement system. Incomplete penetrance of the disease in individuals carrying these mutations is, however, relatively frequent. Here, we report the identification of a large, multiple affected aHUS pedigree in which there is independent segregation of three different aHUS risk factors: a MCP missense mutation (c.-598C>T; Pro165Ser) that decreases MCP expression on the cell surface, a dinucleotide insertion in the coding sequence of factor I (c.-1610insAT) that introduces a premature stop codon in the factor I protein, and the MCPggaac SNP haplotype block that was previously shown to decrease the transcription activity from the MCP promoter. Interestingly, individuals affected by aHUS in the pedigree are only those who have inherited the three aHUS risk factors. These data show an additive effect for mutations in MCP and factor I and provide definitive support to the conclusion that aHUS results from a defective protection of cellular surfaces from complement activation. Furthermore, they help to explain the incomplete penetrance of the disease, illustrating that concurrence of multiple hits in complement regulatory proteins may be necessary to significantly impair host tissue protection and to confer susceptibility to aHUS.

  5. Enzyme-Instructed Self-Assembly of Small d-Peptides as a Multiple-Step Process for Selectively Killing Cancer Cells

    PubMed Central

    2016-01-01

    Selective inhibition of cancer cells remains a challenge in chemotherapy. Here we report the molecular and cellular validation of enzyme-instructed self-assembly (EISA) as a multiple step process for selectively killing cancer cells that overexpress alkaline phosphatases (ALPs). We design and synthesize two kinds of d-tetrapeptide containing one or two phosphotyrosine residues and with the N-terminal capped by a naphthyl group. Upon enzymatic dephosphorylation, these d-tetrapeptides turn into self-assembling molecules to form nanofibers in water. Incubating these d-tetrapeptides with several cancer cell lines and one normal cell line, the unphosphorylated d-tetrapeptides are innocuous to all the cell lines, the mono- and diphosphorylated d-tetrapeptides selectively inhibit the cancer cells, but not the normal cell. The monophosphorylated d-tetrapeptides exhibit more potent inhibitory activity than the diphosphorylated d-tetrapeptides do; the cancer cell lines express higher level of ALPs are more susceptible to inhibition by the phosphorylated d-tetrapeptides; the precursors of d-tetrapeptides that possess higher self-assembling abilities exhibit higher inhibitory activities. These results confirm the important role of enzymatic reaction and self-assembly. Using uncompetitive inhibitors of ALPs and fluorescent d-tetrapeptides, we delineate that the enzyme catalyzed dephosphorylation and the self-assembly steps, together, result in the localization of the nanofibers of d-tetrapeptides for killing the cancer cells. We find that the cell death modality likely associates with the cell type and prove the interactions between nanofibers and the death receptors. This work illustrates a paradigm-shifting and biomimetic approach and contributes useful molecular insights for the development of spatiotemporal defined supramolecular processes/assemblies as potential anticancer therapeutics. PMID:26966844

  6. The ASYMMETRIC LEAVES Complex Employs Multiple Modes of Regulation to Affect Adaxial-Abaxial Patterning and Leaf Complexity[OPEN

    PubMed Central

    Husbands, Aman Y.; Benkovics, Anna H.; Nogueira, Fabio T.S.; Lodha, Mukesh; Timmermans, Marja C.P.

    2015-01-01

    Flattened leaf architecture is not a default state but depends on positional information to precisely coordinate patterns of cell division in the growing primordium. This information is provided, in part, by the boundary between the adaxial (top) and abaxial (bottom) domains of the leaf, which are specified via an intricate gene regulatory network whose precise circuitry remains poorly defined. Here, we examined the contribution of the ASYMMETRIC LEAVES (AS) pathway to adaxial-abaxial patterning in Arabidopsis thaliana and demonstrate that AS1-AS2 affects this process via multiple, distinct regulatory mechanisms. AS1-AS2 uses Polycomb-dependent and -independent mechanisms to directly repress the abaxial determinants MIR166A, YABBY5, and AUXIN RESPONSE FACTOR3 (ARF3), as well as a nonrepressive mechanism in the regulation of the adaxial determinant TAS3A. These regulatory interactions, together with data from prior studies, lead to a model in which the sequential polarization of determinants, including AS1-AS2, explains the establishment and maintenance of adaxial-abaxial leaf polarity. Moreover, our analyses show that the shared repression of ARF3 by the AS and trans-acting small interfering RNA (ta-siRNA) pathways intersects with additional AS1-AS2 targets to affect multiple nodes in leaf development, impacting polarity as well as leaf complexity. These data illustrate the surprisingly multifaceted contribution of AS1-AS2 to leaf development showing that, in conjunction with the ta-siRNA pathway, AS1-AS2 keeps the Arabidopsis leaf both flat and simple. PMID:26589551

  7. The ASYMMETRIC LEAVES Complex Employs Multiple Modes of Regulation to Affect Adaxial-Abaxial Patterning and Leaf Complexity.

    PubMed

    Husbands, Aman Y; Benkovics, Anna H; Nogueira, Fabio T S; Lodha, Mukesh; Timmermans, Marja C P

    2015-12-01

    Flattened leaf architecture is not a default state but depends on positional information to precisely coordinate patterns of cell division in the growing primordium. This information is provided, in part, by the boundary between the adaxial (top) and abaxial (bottom) domains of the leaf, which are specified via an intricate gene regulatory network whose precise circuitry remains poorly defined. Here, we examined the contribution of the ASYMMETRIC LEAVES (AS) pathway to adaxial-abaxial patterning in Arabidopsis thaliana and demonstrate that AS1-AS2 affects this process via multiple, distinct regulatory mechanisms. AS1-AS2 uses Polycomb-dependent and -independent mechanisms to directly repress the abaxial determinants MIR166A, YABBY5, and AUXIN RESPONSE FACTOR3 (ARF3), as well as a nonrepressive mechanism in the regulation of the adaxial determinant TAS3A. These regulatory interactions, together with data from prior studies, lead to a model in which the sequential polarization of determinants, including AS1-AS2, explains the establishment and maintenance of adaxial-abaxial leaf polarity. Moreover, our analyses show that the shared repression of ARF3 by the AS and trans-acting small interfering RNA (ta-siRNA) pathways intersects with additional AS1-AS2 targets to affect multiple nodes in leaf development, impacting polarity as well as leaf complexity. These data illustrate the surprisingly multifaceted contribution of AS1-AS2 to leaf development showing that, in conjunction with the ta-siRNA pathway, AS1-AS2 keeps the Arabidopsis leaf both flat and simple.

  8. Release of a single neurotransmitter from an identified interneuron coherently affects motor output on multiple time scales.

    PubMed

    Dacks, Andrew M; Weiss, Klaudiusz R

    2013-05-01

    Neurotransmitters can have diverse effects that occur over multiple time scales often making the consequences of neurotransmission difficult to predict. To explore the consequences of this diversity, we used the buccal ganglion of Aplysia to examine the effects of GABA release by a single interneuron, B40, on the intrinsic properties and motor output of the radula closure neuron B8. B40 induces a picrotoxin-sensitive fast IPSP lasting milliseconds in B8 and a slow EPSP lasting seconds. We found that the excitatory effects of this slow EPSP are also mediated by GABA. Together, these two GABAergic actions structure B8 firing in a pattern characteristic of ingestive programs. Furthermore, we found that repeated B40 stimulation induces a persistent increase in B8 excitability that was occluded in the presence of the GABA B receptor agonist baclofen, suggesting that GABA affects B8 excitability over multiple time scales. The phasing of B8 activity during the feeding motor programs determines the nature of the behavior elicited during that motor program. The persistent increase in B8 excitability induced by B40 biased the activity of B8 during feeding motor programs causing the motor programs to become more ingestive in nature. Thus, a single transmitter released from a single interneuron can have consequences for motor output that are expressed over multiple time scales. Importantly, despite the differences in their signs and temporal characteristics, the three actions of B40 are coherent in that they promote B8 firing patterns that are characteristic of ingestive motor outputs.

  9. Next Step for STEP

    SciTech Connect

    Wood, Claire; Bremner, Brenda

    2013-08-09

    The Siletz Tribal Energy Program (STEP), housed in the Tribe’s Planning Department, will hire a data entry coordinator to collect, enter, analyze and store all the current and future energy efficiency and renewable energy data pertaining to administrative structures the tribe owns and operates and for homes in which tribal members live. The proposed data entry coordinator will conduct an energy options analysis in collaboration with the rest of the Siletz Tribal Energy Program and Planning Department staff. An energy options analysis will result in a thorough understanding of tribal energy resources and consumption, if energy efficiency and conservation measures being implemented are having the desired effect, analysis of tribal energy loads (current and future energy consumption), and evaluation of local and commercial energy supply options. A literature search will also be conducted. In order to educate additional tribal members about renewable energy, we will send four tribal members to be trained to install and maintain solar panels, solar hot water heaters, wind turbines and/or micro-hydro.

  10. cAMP-pKA signaling regulates multiple steps of fungal infection cooperatively with Cmk1 MAP kinase in Colletotrichum lagenarium.

    PubMed

    Yamauchi, Junko; Takayanagi, Naoyuki; Komeda, Kenichi; Takano, Yoshitaka; Okuno, Tetsuro

    2004-12-01

    In Colletotrichum lagenarium, RPK1 encoding the regulatory subunit of PKA is required for pathogenicity. From the rpkl mutant that forms small colonies, we isolated three growth-suppressor mutants. All rpk1-suppressor mutants are nonpathogenic and contain amino acid changes in the PKA catalytic subunit Cpkl. To assess the roles of cyclic AMP (cAMP) signaling in detail, we generated knockout mutants of CPK1 and the adenylate cyclase gene CAC1. The cpk1 and cac1 mutants are nonpathogenic on cucumber. Interestingly, both of the mutants germinated poorly, suggesting involvement of cAMP signaling in germination. Germination defect in the cpk1 and cac1 mutants is partially rescued by incubation of the conidia at lower concentrations. Germinating conidia of the cpk1 and cac1 mutants can form appressoria, but the appressoria formed by them are nonfunctional, like those of the rpk1 mutant. Cytological analysis indicates that the appressoria of the cpk1 mutant contain larger numbers of lipid bodies compared with the wild type, whereas lipid levels in the rpk1 mutants are lower, suggesting cAMP-mediated regulation of lipid metabolism for appressorium functionality. Furthermore, the cpk1 and cacl mutants have a defect in infectious growth in plant. In C. lagenarium, Cmkl mitogen-activated protein kinase (MAPK) regulates germination, appressorium formation, and infectious growth. These results suggest that cAMP signaling controls multiple steps of fungal infection in cooperative regulation with Cmkl MAPK in C. lagenarium.

  11. Mutations in Nonconserved Domains of Ty3 Integrase Affect Multiple Stages of the Ty3 Life Cycle

    PubMed Central

    Nymark-McMahon, M. Henrietta; Sandmeyer, Suzanne B.

    1999-01-01

    Ty3, a retroviruslike element of Saccharomyces cerevisiae, transposes into positions immediately upstream of RNA polymerase III-transcribed genes. The Ty3 integrase (IN) protein is required for integration of the replicated, extrachromosomal Ty3 DNA. In retroviral IN, a conserved core region is sufficient for strand transfer activity. In this study, charged-to-alanine scanning mutagenesis was used to investigate the roles of the nonconserved amino- and carboxyl-terminal regions of Ty3 IN. Each of the 20 IN mutants was defective for transposition, but no mutant was grossly defective for capsid maturation. All mutations affecting steady-state levels of mature IN protein resulted in reduced levels of replicated DNA, even when polymerase activity was not grossly defective as measured by exogenous reverse transcriptase activity assay. Thus, IN could contribute to nonpolymerase functions required for DNA production in vivo or to the stability of the DNA product. Several mutations in the carboxyl-terminal domain resulted in relatively low levels of processed 3′ ends of the replicated DNA, suggesting that this domain may be important for binding of IN to the long terminal repeat. Another class of mutants produced wild-type amounts of DNA with correctly processed 3′ ends. This class could include mutants affected in nuclear entry and target association. Collectively, these mutations demonstrate that in vivo, within the preintegration complex, IN performs a central role in coordinating multiple late stages of the retrotransposition life cycle. PMID:9847351

  12. Chromothripsis in healthy individuals affects multiple protein-coding genes and can result in severe congenital abnormalities in offspring.

    PubMed

    de Pagter, Mirjam S; van Roosmalen, Markus J; Baas, Annette F; Renkens, Ivo; Duran, Karen J; van Binsbergen, Ellen; Tavakoli-Yaraki, Masoumeh; Hochstenbach, Ron; van der Veken, Lars T; Cuppen, Edwin; Kloosterman, Wigard P

    2015-04-02

    Chromothripsis represents an extreme class of complex chromosome rearrangements (CCRs) with major effects on chromosomal architecture. Although recent studies have associated chromothripsis with congenital abnormalities, the incidence and pathogenic effects of this phenomenon require further investigation. Here, we analyzed the genomes of three families in which chromothripsis rearrangements were transmitted from a mother to her child. The chromothripsis in the mothers resulted in completely balanced rearrangements involving 8-23 breakpoint junctions across three to five chromosomes. Two mothers did not show any phenotypic abnormalities, although 3-13 protein-coding genes were affected by breakpoints. Unbalanced but stable transmission of a subset of the derivative chromosomes caused apparently de novo complex copy-number changes in two children. This resulted in gene-dosage changes, which are probably responsible for the severe congenital phenotypes of these two children. In contrast, the third child, who has a severe congenital disease, harbored all three chromothripsis chromosomes from his healthy mother, but one of the chromosomes acquired de novo rearrangements leading to copy-number changes. These results show that the human genome can tolerate extreme reshuffling of chromosomal architecture, including breakage of multiple protein-coding genes, without noticeable phenotypic effects. The presence of chromothripsis in healthy individuals affects reproduction and is expected to substantially increase the risk of miscarriages, abortions, and severe congenital disease.

  13. Cinacalcet therapy in patients affected by primary hyperparathyroidism associated to Multiple Endocrine Neoplasia Syndrome type 1 (MEN1).

    PubMed

    Giusti, Francesca; Cianferotti, Luisella; Gronchi, Giorgio; Cioppi, Federica; Masi, Laura; Faggiano, Antongiulio; Colao, Annamaria; Ferolla, Piero; Brandi, Maria Luisa

    2016-06-01

    Primary hyperparathyroidism is the main endocrinopathy associated with Multiple Endocrine Neoplasia type 1 syndrome. Cinacalcet is a calcimimetic agent licensed for the treatment of secondary hyperparathyroidism in patients with end-stage renal disease, and for the reduction of marked hypercalcemia in patients with parathyroid carcinoma and sporadic hyperparathyroidism requiring surgery but for whom parathyroidectomy is contraindicated. It may provide a medical alternative for the management of primary hyperparathyroidism in subjects affected by Multiple Endocrine Neoplasia type 1. In this longitudinal, intervention study, 33 MEN1 patients had been enrolled, 10 males and 23 females with a mean age of 40 ± 11.9 years, range 20-63. Primary hyperparathyroidism was the first clinical manifestation in 12 patients. All subjects commenced with Cinacalcet 30 mg/day, 22 patients starting therapy with calcimimetics as an alternative to surgery, and 11 patients opting for the medication after the onset of persistent post-surgical primary hyperparathyroidism. Duration of follow-up was 12 months. The results of this study show significant reductions in serum calcium. The changes in hormonal secretions of pituitary and gastroenteropancreatic glands were not significant, demonstrating the overall safety of this drug in this disease. Cinacalcet has been well tolerated by 28 patients, whereas five individuals complained of heartburn and grade 1 nausea, which did not prevent the completion of the study. In conclusion, Cinacalcet has resulted to be well tolerated and safe in patients with MEN1 syndrome and the calcium homeostasis was stabilized.

  14. Prey dispersal rate affects prey species composition and trait diversity in response to multiple predators in metacommunities.

    PubMed

    Howeth, Jennifer G; Leibold, Mathew A

    2010-09-01

    1. Recent studies indicate that large-scale spatial processes can alter local community structuring mechanisms to determine local and regional assemblages of predators and their prey. In metacommunities, this may occur when the functional diversity represented in the regional predator species pool interacts with the rate of prey dispersal among local communities to affect prey species diversity and trait composition at multiple scales. 2. Here, we test for effects of prey dispersal rate and spatially and temporally heterogeneous predation from functionally dissimilar predators on prey structure in pond mesocosm metacommunities. An experimental metacommunity consisted of three pond mesocosm communities supporting two differentially size-selective invertebrate predators and their zooplankton prey. In each metacommunity, two communities maintained constant predation and supported either Gyrinus sp. (Coleoptera) or Notonecta ungulata (Hemiptera) predators generating a spatial prey refuge while the third community supported alternating predation from Gyrinus sp. and N. ungulata generating a temporal prey refuge. Mesocosm metacommunities were connected at either low (0.7% day(-1)) or high (10% day(-1)) planktonic prey dispersal. The diversity, composition and body size of zooplankton prey were measured at local and regional (metacommunity) scales. 3. Metacommunities experiencing the low prey dispersal rate supported the greatest regional prey species diversity (H') and evenness (J'). Neither dispersal rate nor predation regime affected local prey diversity or evenness. The spatial prey refuge at low dispersal maintained the largest difference in species composition and body size diversity between communities under Gyrinus and Notonecta predation, suggesting that species sorting was operating at the low dispersal rate. There was no effect of dispersal rate on species diversity or body size distribution in the temporal prey refuge. 4. The frequency distribution, but not

  15. The Aurora-A inhibitor MLN8237 affects multiple mitotic processes and induces dose-dependent mitotic abnormalities and aneuploidy.

    PubMed

    Asteriti, Italia Anna; Di Cesare, Erica; De Mattia, Fabiola; Hilsenstein, Volker; Neumann, Beate; Cundari, Enrico; Lavia, Patrizia; Guarguaglini, Giulia

    2014-08-15

    Inhibition of Aurora kinase activity by small molecules is being actively investigated as a potential anti-cancer strategy. A successful therapeutic use of Aurora inhibitors relies on a comprehensive understanding of the effects of inactivating Aurora kinases on cell division, a challenging aim given the pleiotropic roles of those kinases during mitosis. Here we have used the Aurora-A inhibitor MLN8237, currently under phase-I/III clinical trials, in dose-response assays in U2OS human cancer cells synchronously proceeding towards mitosis. By following the behaviour and fate of single Aurora-inhibited cells in mitosis by live microscopy, we show that MLN8237 treatment affects multiple processes that are differentially sensitive to the loss of Aurora-A function. A role of Aurora-A in controlling the orientation of cell division emerges. MLN8237 treatment, even in high doses, fails to induce efficient elimination of dividing cells, or of their progeny, while inducing significant aneuploidy in daughter cells. The results of single-cell analyses show a complex cellular response to MLN8237 and evidence that its effects are strongly dose-dependent: these issues deserve consideration in the light of the design of strategies to kill cancer cells via inhibition of Aurora kinases.

  16. The Aurora-A inhibitor MLN8237 affects multiple mitotic processes and induces dose-dependent mitotic abnormalities and aneuploidy

    PubMed Central

    Asteriti, Italia Anna; Cesare, Erica Di; Mattia, Fabiola De; Hilsenstein, Volker; Neumann, Beate; Cundari, Enrico; Lavia, Patrizia; Guarguaglini, Giulia

    2014-01-01

    Inhibition of Aurora kinase activity by small molecules is being actively investigated as a potential anti-cancer strategy. A successful therapeutic use of Aurora inhibitors relies on a comprehensive understanding of the effects of inactivating Aurora kinases on cell division, a challenging aim given the pleiotropic roles of those kinases during mitosis. Here we have used the Aurora-A inhibitor MLN8237, currently under phase-I/III clinical trials, in dose-response assays in U2OS human cancer cells synchronously proceeding towards mitosis. By following the behaviour and fate of single Aurora-inhibited cells in mitosis by live microscopy, we show that MLN8237 treatment affects multiple processes that are differentially sensitive to the loss of Aurora-A function. A role of Aurora-A in controlling the orientation of cell division emerges. MLN8237 treatment, even in high doses, fails to induce efficient elimination of dividing cells, or of their progeny, while inducing significant aneuploidy in daughter cells. The results of single-cell analyses show a complex cellular response to MLN8237 and evidence that its effects are strongly dose-dependent: these issues deserve consideration in the light of the design of strategies to kill cancer cells via inhibition of Aurora kinases. PMID:25153724

  17. A non-synonymous single-nucleotide polymorphism associated with multiple sclerosis risk affects the EVI5 interactome

    PubMed Central

    Didonna, Alessandro; Isobe, Noriko; Caillier, Stacy J.; Li, Kathy H.; Burlingame, Alma L.; Hauser, Stephen L.; Baranzini, Sergio E.; Patsopoulos, Nikolaos A.; Oksenberg, Jorge R.

    2015-01-01

    Despite recent progress in the characterization of genetic loci associated with multiple sclerosis (MS) risk, the ubiquitous linkage disequilibrium operating across the genome has stalled efforts to distinguish causative variants from proxy single-nucleotide polymorphisms (SNPs). Here, we have identified through fine mapping and meta-analysis EVI5 as the most plausible disease risk gene within the 1p22.1 locus. We further show that an exonic SNP associated with risk induces changes in superficial hydrophobicity patterns of the coiled-coil domain of EVI5, which, in turns, affects the EVI5 interactome. Immunoprecipitation of wild-type and mutated EVI5 followed by mass spectrometry generated a roster of disease-specific interactors functionally linked to lipid metabolism. Among the exclusive binding partners of the risk variant, we describe the novel interaction with sphingosine 1-phosphate lyase (SGPL1)—a key enzyme for the creation of the sphingosine-1 phosphate gradient, which is relevant to the pathogenic process and therapeutic management of MS. PMID:26433934

  18. Intramolecular N-Glycan/Polypeptide Interactions Observed at Multiple N-Glycan Remodeling Steps through [13C,15N]-N-Acetylglucosamine Labeling of Immunoglobulin G1

    PubMed Central

    2014-01-01

    Asparagine-linked (N) glycosylation is a common eukaryotic protein modification that affects protein folding, function, and stability through intramolecular interactions between N-glycan and polypeptide residues. Attempts to characterize the structure–activity relationship of each N-glycan are hindered by inherent properties of the glycoprotein, including glycan conformational and compositional heterogeneity. These limitations can be addressed by using a combination of nuclear magnetic resonance techniques following enzymatic glycan remodeling to simultaneously generate homogeneous glycoforms. However, widely applicable methods do not yet exist. To address this technological gap, immature glycoforms of the immunoglobulin G1 fragment crystallizable (Fc) were isolated in a homogeneous state and enzymatically remodeled with [13C,15N]-N-acetylglucosamine (GlcNAc). UDP-[13C,15N]GlcNAc was synthesized enzymatically in a one-pot reaction from [13C]glucose and [15N-amido]glutamine. Modifying Fc with recombinantly expressed glycosyltransferases (Gnt1 and Gnt2) and UDP-[13C,15N]GlcNAc resulted in complete glycoform conversion as judged by mass spectrometry. Two-dimensional heteronuclear single-quantum coherence spectra of the Gnt1 product, containing a single [13C,15N]GlcNAc residue on each N-glycan, showed that the N-glycan is stabilized through interactions with polypeptide residues. Similar spectra of homogeneous glycoforms, halted at different points along the N-glycan remodeling pathway, revealed the presence of an increased level of interaction between the N-glycan and polypeptide at each step, including mannose trimming, as the N-glycan was converted to a complex-type, biantennary form. Thus, conformational restriction increases as Fc N-glycan maturation proceeds. Gnt1 and Gnt2 catalyze fundamental reactions in the synthesis of every glycoprotein with a complex-type N-glycan; thus, the strategies presented herein can be applied to a broad range of glycoprotein

  19. St. John's wort extract and hyperforin inhibit multiple phosphorylation steps of cytokine signaling and prevent inflammatory and apoptotic gene induction in pancreatic β cells.

    PubMed

    Novelli, Michela; Menegazzi, Marta; Beffy, Pascale; Porozov, Svetlana; Gregorelli, Alex; Giacopelli, Daniela; De Tata, Vincenzo; Masiello, Pellegrino

    2016-12-01

    The extract of the herbaceous plant St. John's wort (SJW) and its phloroglucinol component hyperforin (HPF) were previously shown to inhibit cytokine-induced STAT-1 and NF-κB activation and prevent damage in pancreatic β cells. To further clarify the mechanisms underlying their protective effects, we evaluated the phosphorylation state of various factors of cytokine signaling pathways and the expression of target genes involved in β-cell function, inflammatory response and apoptosis induction. In the INS-1E β-cell line, exposed to a cytokine mixture with/without SJW extract (2-5μg/ml) or HPF (1-5μM), protein phosphorylation was assessed by western blotting and expression of target genes by real-time quantitative PCR. SJW and HPF markedly inhibited, in a dose-dependent manner (from 60 to 100%), cytokine-induced activating phosphorylations of STAT-1, NF-κB p65 subunit and IKK (NF-κB inhibitory subunit IκBα kinase). MAPK and Akt pathways were also modulated by the vegetal compounds through hindrance of p38 MAPK, ERK1/2, JNK and Akt phosphorylations, each reduced by at least 65% up to 100% at the higher dose. Consistently, SJW and HPF a) abolished cytokine-induced mRNA expression of pro-inflammatory genes; b) avoided down-regulation of relevant β-cell functional/differentiation genes; c) corrected cytokine-driven imbalance between pro- and anti-apoptotic factors, by fully preventing up-regulation of pro-apoptotic genes and preserving expression or function of anti-apoptotic Bcl-2 family members; d) protected INS-1E cells against cytokine-induced apoptosis. In conclusion, SJW extract and HPF exert their protective effects through simultaneous inhibition of multiple phosphorylation steps along various cytokine signaling pathways and consequent restriction of inflammatory and apoptotic gene expression. Thus, they have a promising therapeutic potential for the prevention or limitation of immune-mediated β-cell dysfunction and damage leading to type 1 diabetes.

  20. ST. JOHN's wort extract and hyperforin inhibit multiple phosphorylation steps of cytokine signaling and prevent inflammatory and apoptotic gene induction in pancreatic β cells.

    PubMed

    Novelli, Michela; Menegazzi, Marta; Beffy, Pascale; Porozov, Svetlana; Gregorelli, Alex; Giacopelli, Daniela; Tata, Vincenzo De; Masiello, Pellegrino

    2016-10-22

    The extract of the herbaceous plant St. John's wort (SJW) and its phloroglucinol component hyperforin (HPF) were previously shown to inhibit cytokine-induced STAT-1 and NF-κB activation and prevent damage in pancreatic β cells. To further clarify the mechanisms underlying their protective effects, we evaluated the phosphorylation state of various factors of cytokine signaling pathways and the expression of target genes involved in β-cell function, inflammatory response and apoptosis induction. In the INS-1E β-cell line, exposed to a cytokine mixture with/without SJW extract (2-5μg/ml) or HPF (1-5μM), protein phosphorylation was assessed by Western blotting and expression of target genes by real-time quantitative PCR. SJW and HPF markedly inhibited, in a dose-dependent manner (from 60 to 100%), cytokine-induced activating phosphorylations of STAT-1, NF-κB p65 subunit and IKK (NF-κB inhibitory subunit IκBα kinase). MAPK and Akt pathways were also modulated by the vegetal compounds through hindrance of p38 MAPK, ERK1/2, JNK and Akt phosphorylations, each reduced by at least 65% up to 100% at the higher dose. Consistently, SJW and HPF a) abolished cytokine-induced mRNA expression of pro-inflammatory genes; b) avoided down-regulation of relevant β-cell functional/differentiation genes; c) corrected cytokine-driven imbalance between pro- and anti-apoptotic factors, by fully preventing up-regulation of pro-apoptotic genes and preserving expression or function of anti-apoptotic Bcl-2 family members; d) protected INS-1E cells against cytokine-induced apoptosis. In conclusion, SJW extract and HPF exert their protective effects through simultaneous inhibition of multiple phosphorylation steps along various cytokine signaling pathways and consequent restriction of inflammatory and apoptotic gene expression. Thus, they have a promising therapeutic potential for the prevention or limitation of immune-mediated β-cell dysfunction and damage leading to type 1 diabetes.

  1. Multiple-step kinetic mechanism of DNA-independent ATP binding and hydrolysis by Escherichia coli replicative helicase DnaB protein: quantitative analysis using the rapid quench-flow method.

    PubMed

    Rajendran, S; Jezewska, M J; Bujalowski, W

    2000-11-10

    The kinetic mechanism of DNA-independent binding and hydrolysis of ATP by the E. coli replicative helicase DnaB protein has been quantitatively examined using the rapid quench-flow technique. Single-turnover studies of ATP hydrolysis, in a non-interacting active site of the helicase, indicate that bimolecular association of ATP with the site is followed by the reversible hydrolysis of nucleotide triphosphate and subsequent conformational transition of the enzyme-product complex. The simplest mechanism, which describes the data, is a three-step sequential process defined by:¿eqalign¿¿¿rm Helicase+ATP¿&¿mathop¿¿rightleftharpoons¿ ¿k_1¿_¿k_¿-1¿¿¿¿rm (H-ATP)¿¿mathop¿¿rightleftharpoons¿ ¿k_2¿_¿k_¿-2¿¿¿¿rm (H-ADP¿cdot Pi)¿¿cr &¿mathop¿¿rightleftharpoons¿ ¿k_3¿_¿k_¿-3¿¿¿¿rm (H-ADP¿cdot Pi)¿ *¿The sequential character of the mechanism excludes conformational transitions of the DnaB helicase prior to ATP binding. Analysis of relaxation times and amplitudes of the reaction allowed us to estimate all rate and equilibrium constants of partial steps of the proposed mechanism. The intrinsic binding constant for the formation of the (H-ATP) complex is K(ATP)=(1.3+/-0.5)x10(5) M(-1). The analysis of the data indicates that a part of the ATP binding energy originates from induced structural changes of the DnaB protein-ATP complex prior to ATP hydrolysis. The equilibrium constant of the chemical interconversion is K(H)=k(2)/k(-2) approximately 2 while the subsequent conformational transition is characterized by K(3)=k(3)/k(-3) approximately 30. The low value of K(H) and the presence of the subsequent energetically favorable conformational step(s) strongly suggest that free energy is released from the enzyme-product complex in the conformational transitions following the chemical step and before the product release.The combined application of single and multiple-turnover approaches show that all six nucleotide-binding sites of the Dna

  2. Multiple Sclerosis

    MedlinePlus

    Multiple sclerosis (MS) is a nervous system disease that affects your brain and spinal cord. It damages the ... attacks healthy cells in your body by mistake. Multiple sclerosis affects women more than men. It often begins ...

  3. Herding: a new phenomenon affecting medical decision-making in multiple sclerosis care? Lessons learned from DIScUTIR MS

    PubMed Central

    Saposnik, Gustavo; Maurino, Jorge; Sempere, Angel P; Ruff, Christian C; Tobler, Philippe N

    2017-01-01

    Purpose Herding is a phenomenon by which individuals follow the behavior of others rather than deciding independently on the basis of their own private information. A herding-like phenomenon can occur in multiple sclerosis (MS) when a neurologist follows a therapeutic recommendation by a colleague even though it is not supported by best practice clinical guidelines. Limited information is currently available on the role of herding in medical care. The objective of this study was to determine the prevalence (and its associated factors) of herding in the management of MS. Methods We conducted a study among neurologists with expertise in MS care throughout Spain. Participants answered questions regarding the management of 20 case scenarios commonly encountered in clinical practice and completed 3 surveys and 4 experimental paradigms based on behavioral economics. The herding experiment consisted of a case scenario of a 40-year-old woman who has been stable for 3 years on subcutaneous interferon and developed a self-limited neurological event. There were no new magnetic resonance imaging (MRI) lesions. Her neurological examination and disability scores were unchanged. She was advised by an MS neurologist to switch from interferon to fingolimod against best practice guidelines. Multivariable logistic regression analysis was conducted to evaluate factors associated with herding. Results Out of 161 neurologists who were invited to participate, 96 completed the study (response rate: 60%). Herding was present in 75 (78.1%), having a similar prevalence in MS experts and general neurologists (68.8% vs 82.8%; P=0.12). In multivariate analyses, the number of MS patients seen per week was positively associated with herding (odds ratio [OR] 1.08, 95% CI 1.01–1.14). Conversely, physician’s age, gender, years of practice, setting of practice, or risk preferences were not associated with herding. Conclusion Herding was a common phenomenon affecting nearly 8 out of 10

  4. The Drosophila Transcription Factor Dimmed Affects Neuronal Growth and Differentiation in Multiple Ways Depending on Neuron Type and Developmental Stage

    PubMed Central

    Liu, Yiting; Luo, Jiangnan; Nässel, Dick R.

    2016-01-01

    Growth of postmitotic neurons occurs during different stages of development, including metamorphosis, and may also be part of neuronal plasticity and regeneration. Recently we showed that growth of post-mitotic neuroendocrine cells expressing the basic helix loop helix (bHLH) transcription factor Dimmed (Dimm) in Drosophila could be regulated by insulin/IGF signaling and the insulin receptor (dInR). Dimm is also known to confer a secretory phenotype to neuroendocrine cells and can be part of a combinatorial code specifying terminal differentiation in peptidergic neurons. To further understand the mechanisms of Dimm function we ectopically expressed Dimm or Dimm together with dInR in a wide range of Dimm positive and Dimm negative peptidergic neurons, sensory neurons, interneurons, motor neurons, and gut endocrine cells. We provide further evidence that dInR mediated cell growth occurs in a Dimm dependent manner and that one source of insulin-like peptide (DILP) for dInR mediated cell growth in the CNS is DILP6 from glial cells. Expressing both Dimm and dInR in Dimm negative neurons induced growth of cell bodies, whereas dInR alone did not. We also found that Dimm alone can regulate cell growth depending on specific cell type. This may be explained by the finding that the dInR is a direct target of Dimm. Conditional gene targeting experiments showed that Dimm alone could affect cell growth in certain neuron types during metamorphosis or in the adult stage. Another important finding was that ectopic Dimm inhibits apoptosis of several types of neurons normally destined for programmed cell death (PCD). Taken together our results suggest that Dimm plays multiple transcriptional roles at different developmental stages in a cell type-specific manner. In some cell types ectopic Dimm may act together with resident combinatorial code transcription factors and affect terminal differentiation, as well as act in transcriptional networks that participate in long term maintenance

  5. Gait variability in healthy old adults is more affected by a visual perturbation than by a cognitive or narrow step placement demand.

    PubMed

    Francis, Carrie A; Franz, Jason R; O'Connor, Shawn M; Thelen, Darryl G

    2015-09-01

    Gait variability measures have been linked to fall risk in older adults. However, challenging walking tasks may be required to elucidate increases in variability that arise from subtle age-related changes in cognitive processing and sensorimotor function. Hence, the study objective was to investigate the effects of visual perturbations, increased cognitive load, and narrowed step width on gait variability in healthy old and young adults. Eleven old (OA, 71.2±4.2 years) and twelve young (YA, 23.6±3.9 years) adults walked on a treadmill while watching a speed-matched virtual hallway. Subjects walked: (1) normally, (2) with mediolateral visual perturbations, (3) while performing a cognitive task (serial seven subtractions), and (4) with narrowed step width. We computed the mean and variability of step width (SW and SWV, respectively) and length (SL, SLV) over one 3-min trial per condition. Walking normally, old and young adults exhibited similar SWV and SLV. Visual perturbations significantly increased gait variability in old adults (by more than 100% for both SWV and SLV), but not young adults. The cognitive task and walking with narrowed step width did not show any effect on SWV or SLV in either group. The dramatic increase in step width variability when old adults were subjected to mediolateral visual perturbations was likely due to increased reliance on visual feedback for assessing whole-body position. Further work is needed to ascertain whether these findings may reflect sub-clinical balance deficits that could contribute to the increased fall risk seen with advancing age.

  6. Gait variability in healthy old adults is more affected by a visual perturbation than by a cognitive or narrow step placement demand

    PubMed Central

    Francis, Carrie A.; Franz, Jason R.; O'Connor, Shawn M.; Thelen, Darryl G.

    2015-01-01

    Gait variability measures have been linked to fall risk in older adults. However, challenging walking tasks may be required to elucidate increases in variability that arise from subtle age-related changes in cognitive processing and sensorimotor function. Hence, the study objective was to investigate the effects of visual perturbations, increased cognitive load, and narrowed step width on gait variability in healthy old and young adults. Eleven old (OA, 71.2 ± 4.2 years) and twelve young (YA, 23.6 ± 3.9 years) adults walked on a treadmill while watching a speed-matched virtual hallway. Subjects walked: 1) normally, 2) with mediolateral visual perturbations, 3) while performing a cognitive task (serial seven subtractions), and 4) with narrowed step width. We computed the mean and variability of step width (SW and SWV, respectively) and length (SL, SLV) over one three minute trial per condition. Walking normally, old and young adults exhibited similar SWV and SLV. Visual perturbations significantly increased gait variability in old adults (by more than 100% in both SWV and SLV), but not young adults. The cognitive task and walking with narrowed step width did not show any effect on SWV or SLV in either group. The dramatic increase in step width variability when old adults were subjected to mediolateral visual perturbations was likely due to increased reliance on visual feedback for assessing whole body position. Further work is needed to ascertain whether these findings may reflect sub-clinical balance deficits that could contribute to the increased fall risk seen with advancing age. PMID:26233581

  7. To Fish or Not to Fish: Factors at Multiple Scales Affecting Artisanal Fishers' Readiness to Exit a Declining Fishery

    PubMed Central

    Daw, Tim M.; Cinner, Joshua E.; McClanahan, Timothy R.; Brown, Katrina; Stead, Selina M.; Graham, Nicholas A. J.; Maina, Joseph

    2012-01-01

    Globally, fisheries are challenged by the combined impacts of overfishing, degradation of ecosystems and impacts of climate change, while fisheries livelihoods are further pressured by conservation policy imperatives. Fishers' adaptive responses to these pressures, such as exiting from a fishery to pursue alternative livelihoods, determine their own vulnerability, as well as the potential for reducing fishing effort and sustaining fisheries. The willingness and ability to make particular adaptations in response to change, such as exiting from a declining fishery, is influenced by economic, cultural and institutional factors operating at scales from individual fishers to national economies. Previous studies of exit from fisheries at single or few sites, offer limited insight into the relative importance of individual and larger-scale social and economic factors. We asked 599 fishers how they would respond to hypothetical scenarios of catch declines in 28 sites in five western Indian Ocean countries. We investigated how socioeconomic variables at the individual-, household- and site-scale affected whether they would exit fisheries. Site-level factors had the greatest influence on readiness to exit, but these relationships were contrary to common predictions. Specifically, higher levels of infrastructure development and economic vitality - expected to promote exit from fisheries - were associated with less readiness to exit. This may be due to site level histories of exit from fisheries, greater specialisation of fishing households, or higher rewards from fishing in more economically developed sites due to technology, market access, catch value and government subsidies. At the individual and household scale, fishers from households with more livelihood activities, and fishers with lower catch value were more willing to exit. These results demonstrate empirically how adaptive responses to change are influenced by factors at multiple scales, and highlight the importance

  8. Technology-Aided Leisure and Communication Opportunities for Two Post-Coma Persons Emerged from a Minimally Conscious State and Affected by Multiple Disabilities

    ERIC Educational Resources Information Center

    Lancioni, Giulio E.; O'Reilly, Mark F.; Singh, Nirbhay N.; Sigafoos, Jeff; Buonocunto, Francesca; Sacco, Valentina; Navarro, Jorge; Lanzilotti, Crocifissa; De Tommaso, Marina; Megna, Marisa; Oliva, Doretta

    2013-01-01

    This study assessed technology-aided programs for helping two post-coma persons, who had emerged from a minimally conscious state and were affected by multiple disabilities, to (a) engage with leisure stimuli and request caregiver's procedures, (b) send out and listen to text messages for communication with distant partners, and (c) combine…

  9. CH3NH3PbI3 films prepared by combining 1- and 2-step deposition: how crystal growth conditions affect properties.

    PubMed

    Mokhtar, Muhamad Z; Chen, Mu; Whittaker, Eric; Hamilton, Bruce; Aristidou, Nicholas; Ramadan, Simko; Gholinia, Ali; Haque, Saif A; O'Brien, Paul; Saunders, Brian R

    2017-02-24

    Perovskite solar cells continue to attract strong attention because of their unprecedented rate of power conversion efficiency increase. CH3NH3PbI3 (MAPbI3) is the most widely studied perovskite. Typically one-step (1-s) or two-step (2-s) deposition methods are used to prepare MAPbI3 films. Here, we investigate a new MAPbI3 film formation method that combines 1-s and 2-s deposition (termed 1 & 2-s) and uses systematic variation of the stoichiometric mole ratio (x) for the PbI2 + xMAI solutions employed. The PbI2 + xMAI solutions were used to deposit precursor films that were subsequently dipped in MAI solution as a second step to produce the final MAPbI3 films. The morphologies of the 1 & 2-s MAPbI3 films consisted of three crystal types: tree-like microcrystals (≫1 μm), cuboid meso-crystals (∼0.1-1 μm) and nanocrystals (∼50-80 nm). Each crystal type and their proportions were controlled by the value for x. The new 1 & 2-s deposition method produced MAPbI3 films with tuneable optoelectronic properties that were related to those for the conventional 1-s and 2-s films. However, the 1 & 2-s film properties were not simply a combination of those for the 1-s and 2-s films. The 1 & 2-s films showed enhanced light scattering and the photoluminescence spectra displayed a morphologically-dependent red-shift. The unique morphologies for the 1 & 2-s films also strongly influenced PbI2 conversion, power conversion efficiency, hysteresis and recombination. The trends for the performance parameters and hysteresis were compared for devices constructed using spiro-MeOTAD and P3HT and were similar. The 1 & 2-s method should apply to other perovskite formulations and the new insights concerning MAPbI3 crystal growth conditions, morphology and material properties established in this study should also be transferable.

  10. A survey of the parasitic effects and degradation mechanisms affecting the GaAs FET-based IC's: The first step for a technological evaluation

    NASA Astrophysics Data System (ADS)

    Dumas, J. M.

    1991-03-01

    Several parasitic effects which influence GaAs IC performance are reviewed. The main concerns include in bulk trap dependent parasitics such as back (side) gating, and surface induced parasitics such as gate-lag. How the basic understanding of these effects is taken into account in the design rules provided to designers is discussed. Major degradation mechanisms are briefly reviewed. Failure modes observed from high temperature lifetesting conditions are demonstrated to give optimistic median life values when compared with those obtained from low temperatures. Failure criteria are reviewed. In order to assess the effects penalizing the integration and lifetime for both analog and digital IC's, a first step qualification procedure is proposed. It is based on specific test vehicles, issued from Process Control Monitors (PCM) or from specially designed Technology Characterization Vehicles (TCV).

  11. PHOEBE - step by step manual

    NASA Astrophysics Data System (ADS)

    Zasche, P.

    2016-03-01

    An easy step-by-step manual of PHOEBE is presented. It should serve as a starting point for the first time users of PHOEBE analyzing the eclipsing binary light curve. It is demonstrated on one particular detached system also with the downloadable data and the whole procedure is described easily till the final trustworthy fit is being reached.

  12. One-step multiple component isolation from the oil of Crinitaria tatarica (Less) Sojak by preparative capillary gas chromatography with characterization by spectroscopic and spectrometric techniques

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the present work multiple component isolation from the oil of Crinitaria tatarica (Less.) Sojak. by Preparative Capillary Gas Chromatography (PCGC) with characterization by mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy have been carried out. Gas chromatography (GC-FID) ...

  13. Using Multiple Calibration Indices in Order to Capture the Complex Picture of What Affects Students' Accuracy of Feeling of Confidence

    ERIC Educational Resources Information Center

    Boekaerts, Monique; Rozendaal, Jeroen S.

    2010-01-01

    The present study used multiple calibration indices to capture the complex picture of fifth graders' calibration of feeling of confidence in mathematics. Specifically, the effects of gender, type of mathematical problem, instruction method, and time of measurement (before and after problem solving) on calibration skills were investigated. Fourteen…

  14. Predicting probability of occurrence and factors affecting distribution and abundance of three Ozark endemic crayfish species at multiple spatial scales

    USGS Publications Warehouse

    Nolen, Matthew S.; Magoulick, Daniel D.; DiStefano, Robert J.; Imhoff, Emily M.; Wagner, Brian K.

    2014-01-01

    We found that a range of environmental variables were important in predicting crayfish distribution and abundance at multiple spatial scales and their importance was species-, response variable- and scale dependent. We would encourage others to examine the influence of spatial scale on species distribution and abundance patterns.

  15. Pathological complete response in a patient affected by multiple synchronous, breast and lung primary malignancies: a case report and review of the literature.

    PubMed

    Nottegar, A; Luchini, C; Cingarlini, S; Beccari, S; Grego, E; Gilioli, E; Manfrin, E; Bonetti, F

    2016-12-01

    A pathological complete response in a patient affected by multiple synchronous, breast and lung primary malignancies is reported. A 63-year-old woman presented with an invasive ductal carcinoma of the breast and a lung adenocarcinoma. After multidisciplinary discussion, the patient underwent pulmonary left lower lobectomy followed by radio-chemotherapy with cisplatin and vinorelbine and started hormone therapy with letrozole. Ten months later, a left mastectomy with axillary lymph nodes dissection was performed. Histologically, a pathological complete response (pCR) was documented. With a review of the Literature, we discuss the issue of multiple primary malignancies, with its diagnostic and therapeutic implications. In cases of multiple synchronous malignancies it has been highlighted the importance of the choice of the best therapeutic approach for both the malignancies, reducing collateral individual effects.

  16. Does migratory distance affect fuelling in a medium-distance passerine migrant?: results from direct and step-wise simulated magnetic displacements

    PubMed Central

    Ilieva, Mihaela; Bianco, Giuseppe; Åkesson, Susanne

    2016-01-01

    ABSTRACT In birds, fat accumulation before and during migration has been shown to be endogenously controlled and tuned by, among other factors, the Earth's magnetic field. However, our knowledge about the influence of the geomagnetic field on the fuelling in migrating birds is still limited to just a few nocturnally migrating passerine species. In order to study if variations of the magnetic field can also influence the fuelling of both day- and night-migrating passerines, we caught first-year dunnocks (Prunella modularis) and subjected them to three magnetic field conditions simulated by a system of magnetic coils: (1) local geomagnetic field of southern Sweden, (2) magnetic field corresponding to the centre of the expected wintering area, and (3) magnetic field met at the northern limit of the species' breeding distribution. We did not find a difference in mass increase between the birds kept in a local magnetic field and a field resembling their wintering area, irrespectively of the mode of magnetic displacement, i.e. direct or step-wise. However, the dunnocks magnetically displaced north showed a lower rate of fuelling in comparison to the control group, probably due to elevated activity. Compared with previous studies, our results suggest that the fuelling response to magnetic displacements during the migration period is specific to the eco-physiological situation. Future studies need to address if there is an effect of magnetic field manipulation on the level of migratory activity in dunnocks and how widespread the influence of local geomagnetic field parameters is on fuelling decisions in different bird species, which have different migratory strategies, distances and migration history. PMID:26883627

  17. ATP binding and hydrolysis steps of the uni-site catalysis by the mitochondrial F(1)-ATPase are affected by inorganic phosphate.

    PubMed

    Milgrom, Yakov M

    2010-10-01

    The effect of inorganic phosphate (P(i)) on uni-site ATP binding and hydrolysis by the nucleotide-depleted F(1)-ATPase from beef heart mitochondria (ndMF(1)) has been investigated. It is shown for the first time that P(i) decreases the apparent rate constant of uni-site ATP binding by ndMF(1) 3-fold with the K(d) of 0.38+/-0.14mM. During uni-site ATP hydrolysis, P(i) also shifts equilibrium between bound ATP and ADP+P(i) in the direction of ATP synthesis with the K(d) of 0.17+/-0.03mM. However, 10mM P(i) does not significantly affect ATP binding during multi-site catalysis.

  18. Multiple micronutrient-fortified rice affects physical performance and plasma vitamin B-12 and homocysteine concentrations of Indian school children.

    PubMed

    Thankachan, Prashanth; Rah, Jee Hyun; Thomas, Tinku; Selvam, Sumithra; Amalrajan, Vani; Srinivasan, Krishnamachari; Steiger, Georg; Kurpad, Anura V

    2012-05-01

    Fortifying rice with multiple micronutrients could be a promising strategy for combat micronutrient deficiencies in developing countries. We determined the efficacy of extruded rice grains fortified with multiple micronutrients on the prevalence of anemia, micronutrient status, and physical and cognitive performance in 6- to 12-y-old, low-income school children in Bangalore, India. In a randomized, double-blind, controlled trial, 258 children were assigned to 1 of 3 intervention groups to receive rice-based lunch meals fortified with multiple micronutrients with either low-iron (6.25 mg) or high-iron (12.5 mg) concentrations or identical meals with unfortified rice. The meals were provided 6 d/wk for 6 mo. Anthropometric, biochemical, physical performance, and cognitive assessments were taken at baseline and endpoint. At baseline, study groups were comparable, with 61% of the children being anemic. However, only <10% were deficient in iron, vitamin A, and zinc. After 6 mo, plasma vitamin B-12 and homocysteine concentrations (both P < 0.001) as well as physical performance (P < 0.05) significantly improved in the intervention arms. No between-group differences were observed in hemoglobin concentration, anemia, and deficiencies of other micronutrients or cognitive function after 6 mo, but paired analyses revealed a small reduction in anemia prevalence in children in the low-iron group. The fortified rice was efficacious in improving vitamin B-12 status and physical performance in Indian school children.

  19. Proteomic analysis with integrated multiple dimensional liquid chromatography/mass spectrometry based on elution of ion exchange column using pH steps.

    PubMed

    Dai, Jie; Shieh, Chia Hui; Sheng, Quan-Hu; Zhou, Hu; Zeng, Rong

    2005-09-15

    A novel integrated multidimensional liquid chromatography (IMDL) method is demonstrated for the separation of peptide mixtures by two-dimensional HPLC coupled with ion trap mass spectrometry. The method uses an integrated column, containing both strong cation exchange and reversed-phase sections for two-dimensional liquid chromatography. The peptide mixture was fractionated by a pH step using a series of pH buffers, followed by reversed-phase chromatography. Since no salt was used during separation, the integrated multidimensional liquid chromatography can be directly connected to mass spectrometry for peptide analysis. The pH buffers were injected from an autosampler, and the entire process can be carried out on a one-dimensional liquid chromatography system. In a single analysis, the IMDL system, coupled with linear ion trap mass spectrometry, identified more than 2000 proteins in mouse liver. The peptides were eluted according to their pI distribution. The resolution of the pH fractionation is approximately 0.5 pH unit. The method has low overlapping across pH fractions, good resolution of peptide mixture, and good correlation of peptide pIs with pH steps. This method provides a technique for large-scale protein identification using existing one-dimensional HPLC systems.

  20. Gender-specific differences in the process of coping in families with a parent affected by a chronic somatic disease (e.g. multiple sclerosis).

    PubMed

    Steck, B; Amsler, F; Kappos, L; Bürgin, D

    2001-01-01

    Based on the investigation of 52 families and their 87 offspring by means of semistructured interviews, we evaluated the coping abilities of the parent affected by multiple sclerosis (MS), the healthy parent and their children. The results show that the gender of the child significantly influences his or her coping behaviour. Daughters cope better than sons, independently of the gender of the MS-affected parent. Only the daughter's coping is positively affected by age and disease variables. The correlation between the coping behaviour of parents and children is significant between children and their healthy parents and even stronger between children and healthy parents of the same gender. Healthy mothers and daughters cope better with the increasing disability of the father. This is not the case for healthy fathers and sons. Gender seems to be an important moderating factor in chronic parental disease and it has complex effects on the coping capacity of children.

  1. Binding of the wheat germ lectin to Cryptococcus neoformans chitooligomers affects multiple mechanisms required for fungal pathogenesis

    PubMed Central

    Fonseca, Fernanda L.; Guimarães, Allan J.; Kmetzsch, Lívia; Dutra, Fabianno F.; Silva, Fernanda D.; Taborda, Carlos P.; Araujo, Glauber de S.; Frases, Susana; Staats, Charley C.; Bozza, Marcelo T.; Schrank, Augusto; Vainstein, Marilene H.; Nimrichter, Leonardo; Casadevall, Arturo; Rodrigues, Marcio L.

    2015-01-01

    The principal capsular component of Cryptococcus neoformans, glucuronoxylomannan (GXM), interacts with surface glycans, including chitin-like oligomers. Although the role of GXM in cryptococcal infection has been well explored, there is no information on how chitooligomers affect fungal pathogenesis. In this study, surface chitooligomers of C. neoformans were blocked through the use of the wheat germ lectin (WGA) and the effects on animal pathogenesis, interaction with host cells, fungal growth and capsule formation were analyzed. Treatment of C. neoformans cells with WGA followed by infection of mice delayed mortality relative to animals infected with untreated fungal cells. This observation was associated with reduced brain colonization by lectin-treated cryptococci. Blocking chitooligomers also rendered yeast cells less efficient in their ability to associate with phagocytes. WGA did not affect fungal viability, but inhibited GXM release to the extracellular space and capsule formation. In WGA-treated yeast cells, genes that are involved in capsule formation and GXM traffic had their transcription levels decreased in comparison with untreated cells. Our results suggest that cellular pathways required for capsule formation and pathogenic mechanisms are affected by blocking chitin-derived structures at the cell surface of C. neoformans. Targeting chitooligomers with specific ligands may reveal new therapeutic alternatives to control cryptococcosis. PMID:23608320

  2. Dandelion root extract affects colorectal cancer proliferation and survival through the activation of multiple death signalling pathways.

    PubMed

    Ovadje, Pamela; Ammar, Saleem; Guerrero, Jose-Antonio; Arnason, John Thor; Pandey, Siyaram

    2016-11-08

    Dandelion extracts have been studied extensively in recent years for its anti-depressant and anti-inflammatory activity. Recent work from our lab, with in-vitro systems, shows the anti-cancer potential of an aqueous dandelion root extract (DRE) in several cancer cell models, with no toxicity to non-cancer cells. In this study, we examined the cancer cell-killing effectiveness of an aqueous DRE in colon cancer cell models. Aqueous DRE induced programmed cell death (PCD) selectively in > 95% of colon cancer cells, irrespective of their p53 status, by 48 hours of treatment. The anti-cancer efficacy of this extract was confirmed in in-vivo studies, as the oral administration of DRE retarded the growth of human colon xenograft models by more than 90%. We found the activation of multiple death pathways in cancer cells by DRE treatment, as revealed by gene expression analyses showing the expression of genes implicated in programmed cell death. Phytochemical analyses of the extract showed complex multi-component composition of the DRE, including some known bioactive phytochemicals such as α-amyrin, β-amyrin, lupeol and taraxasterol. This suggested that this natural extract could engage and effectively target multiple vulnerabilities of cancer cells. Therefore, DRE could be a non-toxic and effective anti-cancer alternative, instrumental for reducing the occurrence of cancer cells drug-resistance.

  3. Dandelion root extract affects colorectal cancer proliferation and survival through the activation of multiple death signalling pathways

    PubMed Central

    Ovadje, Pamela; Ammar, Saleem; Guerrero, Jose-Antonio; Arnason, John Thor; Pandey, Siyaram

    2016-01-01

    Dandelion extracts have been studied extensively in recent years for its anti-depressant and anti-inflammatory activity. Recent work from our lab, with in-vitro systems, shows the anti-cancer potential of an aqueous dandelion root extract (DRE) in several cancer cell models, with no toxicity to non-cancer cells. In this study, we examined the cancer cell-killing effectiveness of an aqueous DRE in colon cancer cell models. Aqueous DRE induced programmed cell death (PCD) selectively in > 95% of colon cancer cells, irrespective of their p53 status, by 48 hours of treatment. The anti-cancer efficacy of this extract was confirmed in in-vivo studies, as the oral administration of DRE retarded the growth of human colon xenograft models by more than 90%. We found the activation of multiple death pathways in cancer cells by DRE treatment, as revealed by gene expression analyses showing the expression of genes implicated in programmed cell death. Phytochemical analyses of the extract showed complex multi-component composition of the DRE, including some known bioactive phytochemicals such as α-amyrin, β-amyrin, lupeol and taraxasterol. This suggested that this natural extract could engage and effectively target multiple vulnerabilities of cancer cells. Therefore, DRE could be a non-toxic and effective anti-cancer alternative, instrumental for reducing the occurrence of cancer cells drug-resistance. PMID:27564258

  4. The MoSt Project--more steps in multiple sclerosis: a Delphi method consensus initiative for the evaluation of mobility management of MS patients in Italy.

    PubMed

    Capra, Ruggero; Battaglia, Mario Alberto; Gaudioso, Antonio; Lopes, Laura; Paolicelli, Damiano; Paoloni, Marco; Pozzilli, Carlo; Santilli, Valter; Solaro, Claudio; Trojano, Maria

    2014-03-01

    The aim of the study was to identify the main factors that impact mobility impairment in multiple sclerosis (MS) patients in Italy. Clinicians from a large number of Italian MS centers took part in a Delphi process aimed at obtaining consensus statements among the participants. Large consensus was obtained for statements grouped under the following main MS themes: identification of the most useful scales to evaluate mobility, integration of objective evaluation with patient perceptions, impact of walking impairment on daily life, management of the disabled patient using a rehabilitative and pharmacological approach. The consensus statements developed by a large number of experts may be used as a practical reference tool to help physicians treat MS patients with motor impairment.

  5. Multiple brain parenchymal neurocysticercosis with extraocular muscle cysticercosis affecting levator palpebral superioris and superior rectus complex: an unusual association

    PubMed Central

    Verma, Rajesh; Jaiswal, Anupam

    2013-01-01

    An 8-year-old girl presented to the neurology department with a complaint of insidious onset of left-sided ptosis and restricted elevation of the left eye. A CT scan orbit and brain revealed a ring-enhancing lesion in the levator palpebral superioris (LPS) and superior rectus (SR) muscle complex of the left eye and left parietal and right temporal region. She was started on steroid, followed by albendazole with improvement. The LPS/SR complex is the least common site of involvement among extraocular muscles in ocular cysticercosis. Specially, with brain neurocysticercosis (NCC), it is extremely rare. We report an unusual association of multiple brain NCC with ocular cysticercosis involving LPS and SR muscle. PMID:23355567

  6. Common inversion polymorphism at 17q21.31 affects expression of multiple genes in tissue-specific manner

    PubMed Central

    2012-01-01

    Background Chromosome 17q21.31 contains a common inversion polymorphism of approximately 900 kb in populations with European ancestry. Two divergent MAPT haplotypes, H1 and H2 are described with distinct linkage disequilibrium patterns across the region reflecting the inversion status at this locus. The MAPT H1 haplotype has been associated with progressive supranuclear palsy, corticobasal degeneration, Parkinson’s disease and Alzheimer’s disease, while the H2 is linked to recurrent deletion events associated with the 17q21.31 microdeletion syndrome, a disease characterized by developmental delay and learning disability. Results In this study, we investigate the effect of the inversion on the expression of genes in the 17q21.31 region. We find the expression of several genes in and at the borders of the inversion to be affected; specific either to whole blood or different regions of the human brain. The H1 haplotype was found to be associated with an increased expression of LRRC37A4, PLEKH1M and MAPT. In contrast, a decreased expression of MGC57346, LRRC37A and CRHR1 was associated with H1. Conclusions Studies thus far have focused on the expression of MAPT in the inversion region. However, our results show that the inversion status affects expression of other genes in the 17q21.31 region as well. Given the link between the inversion status and different neurological diseases, these genes may also be involved in disease pathology, possibly in a tissue-specific manner. PMID:22950410

  7. Identification of multiple cellular uptake pathways of polystyrene nanoparticles and factors affecting the uptake: relevance for drug delivery systems.

    PubMed

    Firdessa, Rebuma; Oelschlaeger, Tobias A; Moll, Heidrun

    2014-01-01

    Nanoparticles may address challenges by human diseases through improving diagnosis, vaccination and treatment. The uptake mechanism regulates the type of threat a particle poses on the host cells and how a cell responds to it. Hence, understanding the uptake mechanisms and cellular interactions of nanoparticles at the cellular and subcellular level is a prerequisite for their effective biomedical applications. The present study shows the uptake mechanisms of polystyrene nanoparticles and factors affecting their uptake in bone marrow-derived macrophages, 293T kidney epithelial cells and L929 fibroblasts. Labeling with the endocytic marker FM4-64 and transmission electron microscopy studies show that the nanoparticles were internalized rapidly via endocytosis and accumulated in intracellular vesicles. Soon after their internalizations, nanoparticles trafficked to organelles with acidic pH. Analysis of the ultrastructural morphology of the plasma membrane invaginations or extravasations provides clear evidence for the involvement of several uptake routes in parallel to internalize a given type of nanoparticles by mammalian cells, highlighting the complexity of the nanoparticle-cell interactions. Blocking the specific endocytic pathways by different pharmacological inhibitors shows similar outcomes. The potential to take up nanoparticles varies highly among different cell types in a particle sizes-, time- and energy-dependent manner. Furthermore, infection and the activation status of bone marrow-derived macrophages significantly affect the uptake potential of the cells, indicating the need to understand the diseases' pathogenesis to establish effective and rational drug-delivery systems. This study enhances our understanding of the application of nanotechnology in biomedical sciences.

  8. Target enhancement and distractor inhibition affect transitory surround suppression in dual tasks using multiple rapid serial visual presentation streams.

    PubMed

    Wu, Xia; Greenwood, Pamela; Fu, Shimin

    2016-01-01

    Few studies have investigated the interaction between temporal and spatial dimensions on selective attention using dual tasks in the multiple rapid serial visual presentation (RSVP) paradigm. A phenomenon that the surround suppression in space changes over time (termed transitory surround suppression, TSS, in the present study) has been observed, suggesting the existence of this time-space interaction. However, it is still unclear whether target enhancement or distractor inhibition modulates TSS. Four behavioural experiments were conducted to investigate the mechanism of TSS by manipulating the temporal lag and spatial distance factors between two targets embedded in six RSVP streams. The TSS effect was replicated in a study that eliminated confounds of perceptual effects and attentional switch (Experiment 1). However, the TSS disappeared when two targets shared the same colour in a between-subjects design (Experiment 2a) and a within-subject design (Experiment 2b), suggesting the impact of target enhancement on TSS. Moreover, the TSS was larger for within-category than for between-category distractors (Experiment 3), indicating the impact of distractor inhibition on TSS. These two influences on TSS under different processing demands of target and distractor processing were further confirmed in a skeletal design (Experiment 4). Overall, combinative effects of target enhancement and distractor suppression contribute to the mechanisms of time-space interaction in selective attention during visual search.

  9. Statistical evaluation of biogeochemical variables affecting spatiotemporal distributions of multiple free metal ion concentrations in an urban estuary.

    PubMed

    Dong, Zhao; Lewis, Christopher G; Burgess, Robert M; Coull, Brent; Shine, James P

    2016-05-01

    Free metal ion concentrations have been recognized as a better indicator of metal bioavailability in aquatic environments than total dissolved metal concentrations. However, our understanding of the determinants of free ion concentrations, especially in a metal mixture, is limited, due to underexplored techniques for measuring multiple free metal ions simultaneously. In this work, we performed statistical analyses on a large dataset containing repeated measurements of free ion concentrations of Cu, Zn, Pb, Ni, and Cd, the most commonly measured metals in seawater, at five inshore locations in Boston Harbor, previously collected using an in-situ equilibrium-based multi-metal free ion sampler, the 'Gellyfish'. We examined correlations among these five metals by season, and evaluated effects of 10 biogeochemical variables on free ion concentrations over time and location through multivariate regressions. We also explored potential clustering among the five metals through a principal component analysis. We found significant correlations among metals, with varying patterns over season. Our regression results suggest that instead of dissolved metals, pH, salinity, temperature and rainfall were the most significant determinants of free metal ion concentrations. For example, a one-unit decrease in pH was associated with a 2.2 (Cd) to 99 (Cu) times increase in free ion concentrations. This work is among the first to reveal key contributors to spatiotemporal variations in free ion concentrations, and demonstrated the usefulness of the Gellyfish sampler in routine sampling of free ions within metal mixtures and in generating data for statistical analyses.

  10. Quantitative proteome analysis of an antibiotic resistant Escherichia coli exposed to tetracycline reveals multiple affected metabolic and peptidoglycan processes.

    PubMed

    Jones-Dias, Daniela; Carvalho, Ana Sofia; Moura, Inês Barata; Manageiro, Vera; Igrejas, Gilberto; Caniça, Manuela; Matthiesen, Rune

    2017-03-06

    Tetracyclines are among the most commonly used antibiotics administrated to farm animals for disease treatment and prevention, contributing to the worldwide increase in antibiotic resistance in animal and human pathogens. Although tetracycline mechanisms of resistance are well known, the role of metabolism in bacterial reaction to antibiotic stress is still an important assignment and could contribute to the understanding of tetracycline related stress response. In this study, spectral counts-based label free quantitative proteomics has been applied to study the response to tetracycline of the environmental-borne Escherichia coli EcAmb278 isolate soluble proteome. A total of 1484 proteins were identified by high resolution mass spectrometry at a false discovery rate threshold of 1%, of which 108 were uniquely identified under absence of tetracycline whereas 126 were uniquely identified in presence of tetracycline. These proteins revealed interesting difference in e.g. proteins involved in peptidoglycan-based cell wall proteins and energy metabolism. Upon treatment, 12 proteins were differentially regulated showing more than 2-fold change and p<0.05 (p value corrected for multiple testing). This integrated study using high resolution mass spectrometry based label-free quantitative proteomics to study tetracycline antibiotic response in the soluble proteome of resistant E. coli provides novel insight into tetracycline related stress.

  11. Cr(Vi) reduction capacity of activated sludge as affected by nitrogen and carbon sources, microbial acclimation and cell multiplication.

    PubMed

    Ferro Orozco, A M; Contreras, E M; Zaritzky, N E

    2010-04-15

    The objectives of the present work were: (i) to analyze the capacity of activated sludge to reduce hexavalent chromium using different carbon sources as electron donors in batch reactors, (ii) to determine the relationship between biomass growth and the amount of Cr(VI) reduced considering the effect of the nitrogen to carbon source ratio, and (iii) to determine the effect of the Cr(VI) acclimation stage on the performance of the biological chromium reduction assessing the stability of the Cr(VI) reduction capacity of the activated sludge. The highest specific Cr(VI) removal rate (q(Cr)) was attained with cheese whey or lactose as electron donors decreasing in the following order: cheese whey approximately lactose>glucose>citrate>acetate. Batch assays with different nitrogen to carbon source ratio demonstrated that biological Cr(VI) reduction is associated to the cell multiplication phase; as a result, maximum Cr(VI) removal rates occur when there is no substrate limitation. The biomass can be acclimated to the presence of Cr(VI) and generate new cells that maintain the ability to reduce chromate. Therefore, the activated sludge process could be applied to a continuous Cr(VI) removal process.

  12. SUMF1 mutations affecting stability and activity of formylglycine generating enzyme predict clinical outcome in multiple sulfatase deficiency.

    PubMed

    Schlotawa, Lars; Ennemann, Eva Charlotte; Radhakrishnan, Karthikeyan; Schmidt, Bernhard; Chakrapani, Anupam; Christen, Hans-Jürgen; Moser, Hugo; Steinmann, Beat; Dierks, Thomas; Gärtner, Jutta

    2011-03-01

    Multiple Sulfatase Deficiency (MSD) is caused by mutations in the sulfatase-modifying factor 1 gene encoding the formylglycine-generating enzyme (FGE). FGE post translationally activates all newly synthesized sulfatases by generating the catalytic residue formylglycine. Impaired FGE function leads to reduced sulfatase activities. Patients display combined clinical symptoms of single sulfatase deficiencies. For ten MSD patients, we determined the clinical phenotype, FGE expression, localization and stability, as well as residual FGE and sulfatase activities. A neonatal, very severe clinical phenotype resulted from a combination of two nonsense mutations leading to almost fully abrogated FGE activity, highly unstable FGE protein and nearly undetectable sulfatase activities. A late infantile mild phenotype resulted from FGE G263V leading to unstable protein but high residual FGE activity. Other missense mutations resulted in a late infantile severe phenotype because of unstable protein with low residual FGE activity. Patients with identical mutations displayed comparable clinical phenotypes. These data confirm the hypothesis that the phenotypic outcome in MSD depends on both residual FGE activity as well as protein stability. Predicting the clinical course in case of molecularly characterized mutations seems feasible, which will be helpful for genetic counseling and developing therapeutic strategies aiming at enhancement of FGE.

  13. Parameter identifiability and Extended Multiple Studies Analysis of a compartmental model for human vitamin A kinetics: fixing fractional transfer coefficients for the initial steps in the absorptive process.

    PubMed

    Park, Hyunjin; Green, Michael H

    2014-03-28

    In the existing compartmental models of human vitamin A metabolism, parameters related to the absorption of the isotopic oral dose have not been well identified. We hypothesised that fixing some poorly identified parameters related to vitamin A absorption would improve parameter identifiability and add statistical certainty to such models. In the present study, data for serum vitamin A kinetics in nine subjects given [2H8]retinyl acetate orally and a model with absorption fixed at 75 % were used to test this hypothesis. In addition to absorption efficiency, we fixed two other fractional transfer coefficients: one representing the initial processing of the ingested dose and the other representing the direct secretion of retinol bound to retinol-binding protein (RBP) from enterocytes into the plasma. The Windows version of Simulation, Analysis and Modeling software (WinSAAM) was used to fit serum tracer data v. time for each subject. Then, a population model was generated by WinSAAM's Extended Multiple Studies Analysis. All the parameters had fractional standard deviations < 0·5, and none of the pairs of parameters had a correlation coefficient >0·8 (accepted criteria for well-identified parameters). Similar to the values predicted by the original model, total traced mass for retinol was 1160 (sd 468) μmol, and the time for retinol to appear in the plasma bound to RBP was 31·3 (sd 4·4) h. In conclusion, we suggest that this approach holds promise for advancing compartmental modelling of vitamin A kinetics in humans when the dose must be administered orally.

  14. Vitamin D Status Does Not Affect Disability Progression of Patients with Multiple Sclerosis over Three Year Follow-Up

    PubMed Central

    Smolders, Joost; Rolf, Linda; Klinkenberg, Lieke J. J.; van der Linden, Noreen; Meex, Steven; Damoiseaux, Jan; Hupperts, Raymond

    2016-01-01

    Background and Objective The risk of developing multiple sclerosis (MS) as well as MS disease activity is associated with vitamin D (25(OH)D) status. The relationship between the main functional disability hallmark of MS, disability progression, and 25(OH)D status is less well established though, especially not in MS patients with progressive disease. Methods This retrospective follow-up study included 554 MS patients with a serum baseline 25(OH)D level and Expanded Disability Status Scale (EDSS) with a minimum follow-up of three years. Logistic regressions were performed to assess the effect of baseline 25(OH)D status on relapse rate. Repeated measures linear regression analyses were performed to assess the effect on disability and disability progression. Results Baseline deseasonalized 25(OH)D status was associated with subsequent relapse risk (yes/no), but only in the younger MS patients (≤ 37.5 years; OR = 0.872, per 10 nmol/L 25(OH)D, p = 0.041). Baseline 25(OH)D status was not significantly associated with either disability or disability progression, irrespective of MS phenotype. Conclusion Within the physiological range, 25(OH)D status is just significantly associated with the occurrence of relapses in younger MS patients, but is not associated with disability or disability progression over three years follow-up. Whether high dose supplementation to supra physiological 25(OH)D levels prevents disability progression in MS should become clear from long term follow-up of supplementation studies. PMID:27276080

  15. Calpain Cleaves Most Components in the Multiple Aminoacyl-tRNA Synthetase Complex and Affects Their Functions.

    PubMed

    Lei, Hui-Yan; Zhou, Xiao-Long; Ruan, Zhi-Rong; Sun, Wei-Cheng; Eriani, Gilbert; Wang, En-Duo

    2015-10-23

    Nine aminoacyl-tRNA synthetases (aaRSs) and three scaffold proteins form a super multiple aminoacyl-tRNA synthetase complex (MSC) in the human cytoplasm. Domains that have been added progressively to MSC components during evolution are linked by unstructured flexible peptides, producing an elongated and multiarmed MSC structure that is easily attacked by proteases in vivo. A yeast two-hybrid screen for proteins interacting with LeuRS, a representative MSC member, identified calpain 2, a calcium-activated neutral cysteine protease. Calpain 2 and calpain 1 could partially hydrolyze most MSC components to generate specific fragments that resembled those reported previously. The cleavage sites of calpain in ArgRS, GlnRS, and p43 were precisely mapped. After cleavage, their N-terminal regions were removed. Sixty-three amino acid residues were removed from the N terminus of ArgRS to form ArgRSΔN63; GlnRS formed GlnRSΔN198, and p43 formed p43ΔN106. GlnRSΔN198 had a much weaker affinity for its substrates, tRNA(Gln) and glutamine. p43ΔN106 was the same as the previously reported p43-derived apoptosis-released factor. The formation of p43ΔN106 by calpain depended on Ca(2+) and could be specifically inhibited by calpeptin and by RNAi of the regulatory subunit of calpain in vivo. These results showed, for the first time, that calpain plays an essential role in dissociating the MSC and might regulate the canonical and non-canonical functions of certain components of the MSC.

  16. Nicotiana attenuata SIPK, WIPK, NPR1, and Fatty Acid-Amino Acid Conjugates Participate in the Induction of Jasmonic Acid Biosynthesis by Affecting Early Enzymatic Steps in the Pathway1[W][OA

    PubMed Central

    Kallenbach, Mario; Alagna, Fiammetta; Baldwin, Ian Thomas; Bonaventure, Gustavo

    2010-01-01

    Wounding and herbivore attack elicit the rapid (within minutes) accumulation of jasmonic acid (JA) that results from the activation of previously synthesized biosynthetic enzymes. Recently, several regulatory factors that affect JA production have been identified; however, how these regulators affect JA biosynthesis remains at present unknown. Here we demonstrate that Nicotiana attenuata salicylate-induced protein kinase (SIPK), wound-induced protein kinase (WIPK), nonexpressor of PR-1 (NPR1), and the insect elicitor N-linolenoyl-glucose (18:3-Glu) participate in mechanisms affecting early enzymatic steps of the JA biosynthesis pathway. Plants silenced in the expression of SIPK and NPR1 were affected in the initial accumulation of 13-hydroperoxy-linolenic acid (13-OOH-18:3) after wounding and 18:3-Glu elicitation by mechanisms independent of changes in 13-lipoxygenase activity. Moreover, 18:3-Glu elicited an enhanced and rapid accumulation of 13-OOH-18:3 that depended partially on SIPK and NPR1 but was independent of increased 13-lipoxygenase activity. Together, the results suggested that substrate supply for JA production was altered by 18:3-Glu elicitation and SIPK- and NPR1-mediated mechanisms. Consistent with a regulation at the level of substrate supply, we demonstrated by virus-induced gene silencing that a wound-repressed plastidial glycerolipase (NaGLA1) plays an essential role in the induction of de novo JA biosynthesis. In contrast to SIPK and NPR1, mechanisms mediated by WIPK did not affect the production of 13-OOH-18:3 but were critical to control the conversion of this precursor into 12-oxo-phytodienoic acid. These differences could be partially accounted for by reduced allene oxide synthase activity in WIPK-silenced plants. PMID:19897603

  17. Stepped nozzle

    DOEpatents

    Sutton, George P.

    1998-01-01

    An insert which allows a supersonic nozzle of a rocket propulsion system to operate at two or more different nozzle area ratios. This provides an improved vehicle flight performance or increased payload. The insert has significant advantages over existing devices for increasing nozzle area ratios. The insert is temporarily fastened by a simple retaining mechanism to the aft end of the diverging segment of the nozzle and provides for a multi-step variation of nozzle area ratio. When mounted in place, the insert provides the nozzle with a low nozzle area ratio. During flight, the retaining mechanism is released and the insert ejected thereby providing a high nozzle area ratio in the diverging nozzle segment.

  18. Stepped nozzle

    DOEpatents

    Sutton, G.P.

    1998-07-14

    An insert is described which allows a supersonic nozzle of a rocket propulsion system to operate at two or more different nozzle area ratios. This provides an improved vehicle flight performance or increased payload. The insert has significant advantages over existing devices for increasing nozzle area ratios. The insert is temporarily fastened by a simple retaining mechanism to the aft end of the diverging segment of the nozzle and provides for a multi-step variation of nozzle area ratio. When mounted in place, the insert provides the nozzle with a low nozzle area ratio. During flight, the retaining mechanism is released and the insert ejected thereby providing a high nozzle area ratio in the diverging nozzle segment. 5 figs.

  19. Differential Regulation of Multiple Steps in Inositol 1,4,5-Trisphosphate Signaling by Protein Kinase C Shapes Hormone-stimulated Ca2+ Oscillations*

    PubMed Central

    Bartlett, Paula J.; Metzger, Walson; Gaspers, Lawrence D.; Thomas, Andrew P.

    2015-01-01

    How Ca2+ oscillations are generated and fine-tuned to yield versatile downstream responses remains to be elucidated. In hepatocytes, G protein-coupled receptor-linked Ca2+ oscillations report signal strength via frequency, whereas Ca2+ spike amplitude and wave velocity remain constant. IP3 uncaging also triggers oscillatory Ca2+ release, but, in contrast to hormones, Ca2+ spike amplitude, width, and wave velocity were dependent on [IP3] and were not perturbed by phospholipase C (PLC) inhibition. These data indicate that oscillations elicited by IP3 uncaging are driven by the biphasic regulation of the IP3 receptor by Ca2+, and, unlike hormone-dependent responses, do not require PLC. Removal of extracellular Ca2+ did not perturb Ca2+ oscillations elicited by IP3 uncaging, indicating that reloading of endoplasmic reticulum stores via plasma membrane Ca2+ influx does not entrain the signal. Activation and inhibition of PKC attenuated hormone-induced Ca2+ oscillations but had no effect on Ca2+ increases induced by uncaging IP3. Importantly, PKC activation and inhibition differentially affected Ca2+ spike frequencies and kinetics. PKC activation amplifies negative feedback loops at the level of G protein-coupled receptor PLC activity and/or IP3 metabolism to attenuate IP3 levels and suppress the generation of Ca2+ oscillations. Inhibition of PKC relieves negative feedback regulation of IP3 accumulation and, thereby, shifts Ca2+ oscillations toward sustained responses or dramatically prolonged spikes. PKC down-regulation attenuates phenylephrine-induced Ca2+ wave velocity, whereas responses to IP3 uncaging are enhanced. The ability to assess Ca2+ responses in the absence of PLC activity indicates that IP3 receptor modulation by PKC regulates Ca2+ release and wave velocity. PMID:26078455

  20. Multiple injected and natural conservative tracers quantify mixing in a stream confluence affected by acid mine drainage near Silverton, Colorado

    USGS Publications Warehouse

    Schemel, L.E.; Cox, M.H.; Runkel, R.L.; Kimball, B.A.

    2006-01-01

    The acidic discharge from Cement Creek, containing elevated concentrations of dissolved metals and sulphate, mixed with the circumneutral-pH Animas River over a several hundred metre reach (mixing zone) near Silverton, CO, during this study. Differences in concentrations of Ca, Mg, Si, Sr, and SO42- between the creek and the river were sufficiently large for these analytes to be used as natural tracers in the mixing zone. In addition, a sodium chloride (NaCl) tracer was injected into Cement Creek, which provided a Cl- 'reference' tracer in the mixing zone. Conservative transport of the dissolved metals and sulphate through the mixing zone was verified by mass balances and by linear mixing plots relative to the injected reference tracer. At each of seven sites in the mixing zone, five samples were collected at evenly spaced increments of the observed across-channel gradients, as determined by specific conductance. This created sets of samples that adequately covered the ranges of mixtures (mixing ratios, in terms of the fraction of Animas River water, %AR). Concentrations measured in each mixing zone sample and in the upstream Animas River and Cement Creek were used to compute %AR for the reference and natural tracers. Values of %AR from natural tracers generally showed good agreement with values from the reference tracer, but variability in discharge and end-member concentrations and analytical errors contributed to unexpected outlier values for both injected and natural tracers. The median value (MV) %AR (calculated from all of the tracers) reduced scatter in the mixing plots for the dissolved metals, indicating that the MV estimate reduced the effects of various potential errors that could affect any tracer.

  1. Multiple Nicotinic Acetylcholine Receptor Subtypes in the Mouse Amygdala Regulate Affective Behaviors and Response to Social Stress.

    PubMed

    Mineur, Yann S; Fote, Gianna M; Blakeman, Sam; Cahuzac, Emma L M; Newbold, Sylvia A; Picciotto, Marina R

    2016-05-01

    Electrophysiological and neurochemical studies implicate cholinergic signaling in the basolateral amygdala (BLA) in behaviors related to stress. Both animal studies and human clinical trials suggest that drugs that alter nicotinic acetylcholine receptor (nAChR) activity can affect behaviors related to mood and anxiety. Clinical studies also suggest that abnormalities in cholinergic signaling are associated with major depressive disorder, whereas pre-clinical studies have implicated both β2 subunit-containing (β2*) and α7 nAChRs in the effects of nicotine in models of anxiety- and depression-like behaviors. We therefore investigated whether nAChR signaling in the amygdala contributes to stress-mediated behaviors in mice. Local infusion of the non-competitive non-selective nAChR antagonist mecamylamine or viral-mediated downregulation of the β2 or α7 nAChR subunit in the amygdala all induced robust anxiolytic- and antidepressant-like effects in several mouse behavioral models. Further, whereas α7 nAChR subunit knockdown was somewhat more effective at decreasing anxiety-like behavior, only β2 subunit knockdown decreased resilience to social defeat stress and c-fos immunoreactivity in the BLA. In contrast, α7, but not β2, subunit knockdown effectively reversed the effect of increased ACh signaling in a mouse model of depression. These results suggest that signaling through β2* nAChRs is essential for baseline excitability of the BLA, and a decrease in signaling through β2 nAChRs alters anxiety- and depression-like behaviors even in unstressed animals. In contrast, stimulation of α7 nAChRs by acetylcholine may mediate the increased depression-like behaviors observed during the hypercholinergic state observed in depressed individuals.

  2. Multiple injected and natural conservative tracers quantify mixing in a stream confluence affected by acid mine drainage near Silverton, Colorado

    NASA Astrophysics Data System (ADS)

    Schemel, Laurence E.; Cox, Marisa H.; Runkel, Robert L.; Kimball, Briant A.

    2006-08-01

    The acidic discharge from Cement Creek, containing elevated concentrations of dissolved metals and sulphate, mixed with the circumneutral-pH Animas River over a several hundred metre reach (mixing zone) near Silverton, CO, during this study. Differences in concentrations of Ca, Mg, Si, Sr, and SO42- between the creek and the river were sufficiently large for these analytes to be used as natural tracers in the mixing zone. In addition, a sodium chloride (NaCl) tracer was injected into Cement Creek, which provided a Cl- reference tracer in the mixing zone. Conservative transport of the dissolved metals and sulphate through the mixing zone was verified by mass balances and by linear mixing plots relative to the injected reference tracer. At each of seven sites in the mixing zone, five samples were collected at evenly spaced increments of the observed across-channel gradients, as determined by specific conductance. This created sets of samples that adequately covered the ranges of mixtures (mixing ratios, in terms of the fraction of Animas River water, %AR). Concentratis measured in each mixing zone sample and in the upstream Animas River and Cement Creek were used to compute %AR for the reference and natural tracers. Values of %AR from natural tracers generally showed good agreement with values from the reference tracer, but variability in discharge and end-member concentrations and analytical errors contributed to unexpected outlier values for both injected and natural tracers. The median value (MV) %AR (calculated from all of the tracers) reduced scatter in the mixing plots for the dissolved metals, indicating that the MV estimate reduced the effects of various potential errors that could affect any tracer.

  3. Examining the Interplay of Processes Across Multiple Time-Scales: Illustration With the Intraindividual Study of Affect, Health, and Interpersonal Behavior (iSAHIB)

    PubMed Central

    Ram, Nilam; Conroy, David E.; Pincus, Aaron L.; Lorek, Amy; Rebar, Amanda; Roche, Michael J.; Coccia, Michael; Morack, Jennifer; Feldman, Josh; Gerstorf, Denis

    2015-01-01

    Human development is characterized by the complex interplay of processes that manifest at multiple levels of analysis and time-scales. We introduce the Intraindividual Study of Affect, Health and Interpersonal Behavior (iSAHIB) as a model for how multiple time-scale study designs facilitate more precise articulation of developmental theory. Combining age heterogeneity, longitudinal panel, daily diary, and experience sampling protocols, the study made use of smartphone and web-based technologies to obtain intensive longitudinal data from 150 persons age 18–89 years as they completed three 21-day measurement bursts (t = 426 bursts, t = 8,557 days) wherein they provided reports on their social interactions (t = 64,112) as they went about their daily lives. We illustrate how multiple time-scales of data can be used to articulate bioecological models of development and the interplay among more ‘distal’ processes that manifest at ‘slower’ time-scales (e.g., age-related differences and burst-to-burst changes in mental health) and more ‘proximal’ processes that manifest at ‘faster’ time-scales (e.g., changes in context that progress in accordance with the weekly calendar and family influence processes). PMID:26989350

  4. Stanniocalcin-1 Protects a Mouse Model from Renal Ischemia-Reperfusion Injury by Affecting ROS-Mediated Multiple Signaling Pathways

    PubMed Central

    Liu, Dajun; Shang, Huiping; Liu, Ying

    2016-01-01

    Stanniocalcin-1 (STC-1) protects against renal ischemia-reperfusion injury (RIRI). However, the molecular mechanisms remain widely unknown. STC-1 inhibits reactive oxygen species (ROS), whereas most ROS-mediated pathways are associated with ischemic injury. Therefore, to explore the mechanism, the effects of STC-1 on ROS-medicated pathways were studied. Non-traumatic vascular clamps were used to establish RIRI mouse models. The serum levels of STC-1, interleukin-6 (IL-6), interferon (IFN) γ, P53, and capase-3 were measured by ELISA kits. Superoxide dismutase (SOD) and malondialdehyde (MDA) were measured by fluorescence spectrofluorometer. All these molecules changed significantly in a RIRI model mouse when compared with those in a sham control. Kidney cells were isolated from sham and model mice. STC-1 was overexpressed or knockout in these kidney cells. The molecules in ROS-medicated pathways were measured by real-time quantitative PCR and Western blot. The results showed that STC-1 is an effective ROS scavenger. The serum levels of STC-1, MDA and SOD activity were increased while the serum levels of IL-6, iIFN-γ, P53, and capase-3 were decreased in a model group when compared with a sham control (p < 0.05). Furthermore, the levels of STC-1,p53, phosphorylated mitogen-activated protein kinase kinase (p-MEKK-1), c-Jun N-terminal kinase (p-JNK), extracellular signal-regulated kinase (p-ERK), IkB kinase (p-IKK), nuclear factor (NF) κB, apoptosis signal-regulating kinase 1 (ASK-1) and caspase-3 changed significantly in kidney cells isolated from a RIRI model when compared to those isolated from a sham control (p < 0.05). Meanwhile, STC-1 overexpression or silence caused significant changes of the levels of these ROS-mediated molecules. Therefore, STC-1 maybe improve anti-inflammation, anti-oxidant and anti-apoptosis activities by affecting ROS-mediated pathways, especially the phospho-modifications of the respective proteins, resulting in the increase of SOD and

  5. Friction of atomically stepped surfaces

    NASA Astrophysics Data System (ADS)

    Dikken, R. J.; Thijsse, B. J.; Nicola, L.

    2017-03-01

    The friction behavior of atomically stepped metal surfaces under contact loading is studied using molecular dynamics simulations. While real rough metal surfaces involve roughness at multiple length scales, the focus of this paper is on understanding friction of the smallest scale of roughness: atomic steps. To this end, periodic stepped Al surfaces with different step geometry are brought into contact and sheared at room temperature. Contact stress that continuously tries to build up during loading, is released with fluctuating stress drops during sliding, according to the typical stick-slip behavior. Stress release occurs not only through local slip, but also by means of step motion. The steps move along the contact, concurrently resulting in normal migration of the contact. The direction of migration depends on the sign of the step, i.e., its orientation with respect to the shearing direction. If the steps are of equal sign, there is a net migration of the entire contact accompanied by significant vacancy generation at room temperature. The stick-slip behavior of the stepped contacts is found to have all the characteristic of a self-organized critical state, with statistics dictated by step density. For the studied step geometries, frictional sliding is found to involve significant atomic rearrangement through which the contact roughness is drastically changed. This leads for certain step configurations to a marked transition from jerky sliding motion to smooth sliding, making the final friction stress approximately similar to that of a flat contact.

  6. One-step multiple component isolation from the oil of Crinitaria tatarica (Less.) Sojak by preparative capillary gas chromatography with characterization by spectroscopic and spectrometric techniques and evaluation of biological activity.

    PubMed

    Özek, Gulmira; Ishmuratova, Margarita; Tabanca, Nurhayat; Radwan, Mohammed M; Göger, Fatih; Özek, Temel; Wedge, David E; Becnel, James J; Cutler, Stephen J; Can Başer, Kemal H

    2012-03-01

    Gas chromatographic analysis revealed that the oil of Crinitaria tatarica was rich in sabinene (32.1%), β-pinene (8.8%), and two unknown (M+200) compounds (I) and (II) (21.4% and 3.4%). One-step multiple fractionation of the oil and separation of two unknown constituents were performed using preparative capillary gas chromatography connected to preparative fraction collector system. This combination allowed separation and recover of sufficient quantities of two unknown compounds with high purity from complex oil matrix. Separation conditions (column temperature, cooling temperature, flow rate, injection volume, cut time) were optimized to achieve the best isolation and successful collection. The target compounds were separated from the oil using a HP Innowax (Walt & Jennings Scientific, Wilmington, DE, USA) preparative capillary column in rapid one-step manner with 95.0% purity. Trapping of the isolated compounds in collector system was facilitated by cooling with liquid nitrogen. Structure determination was accomplished by spectral analysis including ultraviolet, nuclear magnetic rezonance, and high-resolution electrospray ionization mass spectrometry. Z- (I) and E-artemidin (II) were isolated for the first time from this species. Crinitaria tatarica oil and Z- (I) and E-artemidin (II) were evaluated for biological activity.

  7. The Arabidopsis gene DIG6 encodes a large 60S subunit nuclear export GTPase 1 that is involved in ribosome biogenesis and affects multiple auxin-regulated development processes.

    PubMed

    Zhao, Huayan; Lü, Shiyou; Li, Ruixi; Chen, Tao; Zhang, Huoming; Cui, Peng; Ding, Feng; Liu, Pei; Wang, Guangchao; Xia, Yiji; Running, Mark P; Xiong, Liming

    2015-11-01

    The circularly permuted GTPase large subunit GTPase 1 (LSG1) is involved in the maturation step of the 60S ribosome and is essential for cell viability in yeast. Here, an Arabidopsis mutant dig6 (drought inhibited growth of lateral roots) was isolated. The mutant exhibited multiple auxin-related phenotypes, which included reduced lateral root number, altered leaf veins, and shorter roots. Genetic mapping combined with next-generation DNA sequencing identified that the mutation occurred in AtLSG1-2. This gene was highly expressed in regions of auxin accumulation. Ribosome profiling revealed that a loss of function of AtLSG1-2 led to decreased levels of monosomes, further demonstrating its role in ribosome biogenesis. Quantitative proteomics showed that the expression of certain proteins involved in ribosome biogenesis was differentially regulated, indicating that ribosome biogenesis processes were impaired in the mutant. Further investigations showed that an AtLSG1-2 deficiency caused the alteration of auxin distribution, response, and transport in plants. It is concluded that AtLSG1-2 is integral to ribosome biogenesis, consequently affecting auxin homeostasis and plant development.

  8. Technology-aided leisure and communication opportunities for two post-coma persons emerged from a minimally conscious state and affected by multiple disabilities.

    PubMed

    Lancioni, Giulio E; O'Reilly, Mark F; Singh, Nirbhay N; Sigafoos, Jeff; Buonocunto, Francesca; Sacco, Valentina; Navarro, Jorge; Lanzilotti, Crocifissa; De Tommaso, Marina; Megna, Marisa; Oliva, Doretta

    2013-02-01

    This study assessed technology-aided programs for helping two post-coma persons, who had emerged from a minimally conscious state and were affected by multiple disabilities, to (a) engage with leisure stimuli and request caregiver's procedures, (b) send out and listen to text messages for communication with distant partners, and (c) combine leisure engagement and procedure requests with text messaging within the same sessions. The program for leisure engagement and procedure requests relied on the use of a portable computer with commercial software, and a microswitch for the participants' response. The program for text messaging communication involved the use of a portable computer, a GSM modem, a microswitch for the participants' response, and specifically developed software. Results indicated that the participants were successful at each of the three stages of the study, thus providing relevant evidence concerning performance achievements only minimally documented. The implications of the findings in terms of technology and practical opportunities for post-coma persons with multiple disabilities are discussed.

  9. A mutation in the RET proto-oncogene in Hirschsprung's disease affects the tyrosine kinase activity associated with multiple endocrine neoplasia type 2A and 2B.

    PubMed Central

    Cosma, M P; Panariello, L; Quadro, L; Dathan, N A; Fattoruso, O; Colantuoni, V

    1996-01-01

    We demonstrate that a Hirschsprung (HSCR) mutation in the tyrosine kinase domain of the RET proto-oncogene abolishes in cis the tyrosine-phosphorylation associated with the activating mutation in multiple endocrine neoplasia type 2A (MEN2A) in transiently transfected Cos cells. Yet the double mutant RET2AHS retains the ability to form stable dimers, thus dissociating the dimerization from the phosphorylation potential. Co-transfection experiments with single and double mutants carrying plasmids RET2A and RET2AHS in different ratios drastically reduced the phosphorylation levels of the RET2A protein, suggesting a dominant-negative effect of the HSCR mutation. Also, the phosphorylation associated with the multiple endocrine neoplasia type 2B (MEN2B) allele was affected in experiments with single and double mutants carrying plasmids co-transfected under the same conditions. Finally, analysis of the enzymic activity of MEN2A and MEN2B tumours confirmed the relative levels of tyrosine phosphorylation observed in Cos cells, indicating that this condition, in vivo, may account for the RET transforming potential. PMID:8670046

  10. Significant Low Prevalence of Antibodies Reacting with Simian Virus 40 Mimotopes in Serum Samples from Patients Affected by Inflammatory Neurologic Diseases, Including Multiple Sclerosis

    PubMed Central

    Mazzoni, Elisa; Pietrobon, Silvia; Masini, Irene; Rotondo, John Charles; Gentile, Mauro; Fainardi, Enrico; Casetta, Ilaria; Castellazzi, Massimiliano; Granieri, Enrico; Caniati, Maria Luisa; Tola, Maria Rosaria; Guerra, Giovanni; Martini, Fernanda; Tognon, Mauro

    2014-01-01

    Many investigations were carried out on the association between viruses and multiple sclerosis (MS). Indeed, early studies reported the detections of neurotropic virus footprints in the CNS of patients with MS. In this study, sera from patients affected by MS, other inflammatory (OIND) and non-inflammatory neurologic diseases (NIND) were analyzed for antibodies against the polyomavirus, Simian Virus 40 (SV40). An indirect enzyme-linked immunosorbent assay (ELISA), with two synthetic peptides, which mimic SV40 antigens, was employed to detect specific antibodies in sera from patients affected by MS, OIND, NIND and healthy subjects (HS). Immunologic data indicate that in sera from MS patients antibodies against SV40 mimotopes are detectable with a low prevalence, 6%, whereas in HS of the same mean age, 40 yrs, the prevalence was 22%. The difference is statistically significant (P = 0.001). Significant is also the difference between MS vs. NIND patients (6% vs. 17%; P = 0.0254), whereas no significant difference was detected between MS vs OIND (6% vs 10%; P>0.05). The prevalence of SV40 antibodies in MS patients is 70% lower than that revealed in HS. PMID:25365364

  11. Effectiveness of knowledge translation tools addressing multiple high-burden chronic diseases affecting older adults: protocol for a systematic review alongside a realist review

    PubMed Central

    Kastner, Monika; Perrier, Laure; Hamid, Jemila; Tricco, Andrea C; Cardoso, Roberta; Ivers, Noah M; Liu, Barbara; Marr, Sharon; Holroyd-Leduc, Jayna; Wong, Geoff; Graves, Lisa; Straus, Sharon E

    2015-01-01

    Introduction The burden of chronic disease is a global phenomenon, particularly among people aged 65 years and older. More than half of older adults have more than one chronic disease and their care is not optimal. Chronic disease management (CDM) tools have the potential to meet this challenge but they are primarily focused on a single disease, which fails to address the growing number of seniors with multiple chronic conditions. Methods and analysis We will conduct a systematic review alongside a realist review to identify effective CDM tools that integrate one or more high-burden chronic diseases affecting older adults and to better understand for whom, under what circumstances, how and why they produce their outcomes. We will search MEDLINE, EMBASE, CINAHL, AgeLine and the Cochrane Library for experimental, quasi-experimental, observational and qualitative studies in any language investigating CDM tools that facilitate optimal disease management in one or more high-burden chronic diseases affecting adults aged ≥65 years. Study selection will involve calibration of reviewers to ensure reliability of screening and duplicate assessment of articles. Data abstraction and risk of bias assessment will also be performed independently. Analysis will include descriptive summaries of study and appraisal characteristics, effectiveness of each CDM tool (meta-analysis if appropriate); and a realist programme theory will be developed and refined to explain the outcome patterns within the included studies. Ethics and dissemination Ethics approval is not required for this study. We anticipate that our findings, pertaining to gaps in care across high-burden chronic diseases affecting seniors and highlighting specific areas that may require more research, will be of interest to a wide range of knowledge users and stakeholders. We will publish and present our findings widely, and also plan more active dissemination strategies such as workshops with our key stakeholders

  12. Correlation of mRNA expression and protein abundance affected by multiple sequence features related to translational efficiency in Desulfovibrio vulgaris: A quantitative analysis

    SciTech Connect

    Nie, Lei; Wu, Gang; Zhang, Weiwen

    2006-12-01

    The modest correlation between mRNA expression and protein abundance in large scale datasets is explained in part by experimental challenges, such as technological limitations, and in part by fundamental biological factors in the transcription and translation processes. Among various factors affecting the mRNA-protein correlation, the roles of biological factors related to translation are poorly understood. In this study, using experimental mRNA expression and protein abundance data collected from Desulfovibrio vulgaris by DNA microarray and LC-MS/MS proteomic analysis, we quantitatively examined the effects of several translational-efficiency-related sequence features on mRNA-protein correlation. Three classes of sequence features were investigated according to different translational stages: (1) initiation: Shine-Dalgarno sequences, start codon identity and start codon context; (2) elongation: codon usage and amino acid usage; and (3) termination: stop codon identity and stop codon context. Surprisingly, although it is widely accepted that translation initiation is a rate-limiting step for translation, our results showed that the mRNA-protein correlation was affected the most by the features at elongation stages, codon usage and amino acid composition (7.4-12.6% and 5.3-9.3% of the total variation of mRNA-protein correlation, respectively), followed by stop codon context and the Shine-Dalgarno sequence (2.5-4.2% and 2.3%, respectively). Taken together, all sequence features contributed to 18.4-21.8% of the total variation of mRNA-protein correlation. As the first comprehensive quantitative analysis of the mRNA-protein correlation in bacterial D. vulgaris, our results suggest that the traditional view of the relative importance of various sequence features in prokaryotic protein translation might be questionable.

  13. Spin-orbit interaction in multiple quantum wells

    SciTech Connect

    Hao, Ya-Fei

    2015-01-07

    In this paper, we investigate how the structure of multiple quantum wells affects spin-orbit interactions. To increase the interface-related Rashba spin splitting and the strength of the interface-related Rashba spin-orbit interaction, we designed three kinds of multiple quantum wells. We demonstrate that the structure of the multiple quantum wells strongly affected the interface-related Rashba spin-orbit interaction, increasing the interface-related Rashba spin splitting to up to 26% larger in multiple quantum wells than in a stepped quantum well. We also show that the cubic Dresselhaus spin-orbit interaction similarly influenced the spin relaxation time of multiple quantum wells and that of a stepped quantum well. The increase in the interface-related Rashba spin splitting originates from the relationship between interface-related Rashba spin splitting and electron probability density. Our results suggest that multiple quantum wells can be good candidates for spintronic devices.

  14. Leidenfrost Drop on a Step

    NASA Astrophysics Data System (ADS)

    Lagubeau, Guillaume; Le Merrer, Marie; Clanet, Christophe; Quere, David

    2008-11-01

    When deposited on a hot plate, a water droplet evaporates quickly. However, a vapor film appears under the drop above a critical temperature, called Leidenfrost temperature, which insulates the drop from its substrate. Linke & al (2006) reported a spontaneous movement of such a drop, when deposited on a ratchet. We study here the case of a flat substrate decorated with a single micrometric step. The drop is deposited on the lower part of the plate and pushed towards the step at small constant velocity. If the kinetic energy of the drop is sufficient, it can climb up the step. In that case, depending on the substrate temperature, the drop can either be decelerated or accelerated by the step. We try to understand the dynamics of these drops, especially the regime where they accelerate. Taking advantage of this phenomenon, we could then build a multiple-step setup, making it possible for a Leidenfrost drop to climb stairs.

  15. Tight junctional abnormality in multiple sclerosis white matter affects all calibres of vessel and is associated with blood-brain barrier leakage and active demyelination.

    PubMed

    Kirk, John; Plumb, Jonnie; Mirakhur, Meenakshi; McQuaid, Stephen

    2003-10-01

    Blood-brain barrier (BBB) hyperpermeability in multiple sclerosis (MS) is associated with lesion pathogenesis and has been linked to pathology in microvascular tight junctions (TJs). This study quantifies the uneven distribution of TJ pathology and its association with BBB leakage. Frozen sections from plaque and normal-appearing white matter (NAWM) in 14 cases were studied together with white matter from six neurological and five normal controls. Using single and double immunofluorescence and confocal microscopy, the TJ-associated protein zonula occludens-1 (ZO-1) was examined across lesion types and tissue categories, and in relation to fibrinogen leakage. Confocal image data sets were analysed for 2198 MS and 1062 control vessels. Significant differences in the incidence of TJ abnormalities were detected between the different lesion types in MS and between MS and control white matter. These were frequent in oil-red O (ORO)(+) active plaques, affecting 42% of vessel segments, but less frequent in ORO(-) inactive plaques (23%), NAWM (13%), and normal (3.7%) and neurological controls (8%). A similar pattern was found irrespective of the vessel size, supporting a causal role for diffusible inflammatory mediators. In both NAWM and inactive lesions, dual labelling showed that vessels with the most TJ abnormality also showed most fibrinogen leakage. This was even more pronounced in active lesions, where 41% of vessels in the highest grade for TJ alteration showed severe leakage. It is concluded that disruption of TJs in MS, affecting both paracellular and transcellular paths, contributes to BBB leakage. TJ abnormality and BBB leakage in inactive lesions suggests either failure of TJ repair or a continuing pathological process. In NAWM, it suggests either pre-lesional change or secondary damage. Clinically inapparent TJ pathology has prognostic implications and should be considered when planning disease-modifying therapy.

  16. Key Steps in the Special Review Process

    EPA Pesticide Factsheets

    EPA uses this process when it has reason to believe that the use of a pesticide may result in unreasonable adverse effects on people or the environment. Steps include comprehensive risk and benefit analyses and multiple Position Documents.

  17. Step-Growth Polymerization.

    ERIC Educational Resources Information Center

    Stille, J. K.

    1981-01-01

    Following a comparison of chain-growth and step-growth polymerization, focuses on the latter process by describing requirements for high molecular weight, step-growth polymerization kinetics, synthesis and molecular weight distribution of some linear step-growth polymers, and three-dimensional network step-growth polymers. (JN)

  18. Stepping motor controller

    DOEpatents

    Bourret, Steven C.; Swansen, James E.

    1984-01-01

    A stepping motor is microprocessingly controlled by digital circuitry which monitors the output of a shaft encoder adjustably secured to the stepping motor and generates a subsequent stepping pulse only after the preceding step has occurred and a fixed delay has expired. The fixed delay is variable on a real-time basis to provide for smooth and controlled deceleration.

  19. Stepping motor controller

    DOEpatents

    Bourret, S.C.; Swansen, J.E.

    1982-07-02

    A stepping motor is microprocessor controlled by digital circuitry which monitors the output of a shaft encoder adjustably secured to the stepping motor and generates a subsequent stepping pulse only after the preceding step has occurred and a fixed delay has expired. The fixed delay is variable on a real-time basis to provide for smooth and controlled deceleration.

  20. Step by Step: Avoiding Spiritual Bypass in 12-Step Work

    ERIC Educational Resources Information Center

    Cashwell, Craig S.; Clarke, Philip B.; Graves, Elizabeth G.

    2009-01-01

    With spirituality as a cornerstone, 12-step groups serve a vital role in the recovery community. It is important for counselors to be mindful, however, of the potential for clients to be in spiritual bypass, which likely will undermine the recovery process.

  1. The Effects of the Layoff Process on K-12 Teachers: How Do Multiple Years of Layoff Notices Affect Teacher Attitude, Persistence, and Practice?

    ERIC Educational Resources Information Center

    Mendoza, Cara Ann

    2013-01-01

    This qualitative study examines the effects of multiple years of layoff notices on first- or second-year, K-12 teachers employed in a Northern California, suburban school district in 2008-2009. During years of budget crisis in California, teachers new to the profession experienced ongoing employment uncertainty. This study endeavored to understand…

  2. A Step Circuit Program.

    ERIC Educational Resources Information Center

    Herman, Susan

    1995-01-01

    Aerobics instructors can use step aerobics to motivate students. One creative method is to add the step to the circuit workout. By incorporating the step, aerobic instructors can accommodate various fitness levels. The article explains necessary equipment and procedures, describing sample stations for cardiorespiratory fitness, muscular strength,…

  3. Tumor growth affects the metabonomic phenotypes of multiple mouse non-involved organs in an A549 lung cancer xenograft model

    PubMed Central

    Xu, Shan; Tian, Yuan; Hu, Yili; Zhang, Nijia; Hu, Sheng; Song, Dandan; Wu, Zhengshun; Wang, Yulan; Cui, Yanfang; Tang, Huiru

    2016-01-01

    The effects of tumorigenesis and tumor growth on the non-involved organs remain poorly understood although many research efforts have already been made for understanding the metabolic phenotypes of various tumors. To better the situation, we systematically analyzed the metabolic phenotypes of multiple non-involved mouse organ tissues (heart, liver, spleen, lung and kidney) in an A549 lung cancer xenograft model at two different tumor-growth stages using the NMR-based metabonomics approaches. We found that tumor growth caused significant metabonomic changes in multiple non-involved organ tissues involving numerous metabolic pathways, including glycolysis, TCA cycle and metabolisms of amino acids, fatty acids, choline and nucleic acids. Amongst these, the common effects are enhanced glycolysis and nucleoside/nucleotide metabolisms. These findings provided essential biochemistry information about the effects of tumor growth on the non-involved organs. PMID:27329570

  4. Multiple sclerosis - discharge

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000129.htm Multiple sclerosis - discharge To use the sharing features on this ... Your doctor has told you that you have multiple sclerosis (MS). This disease affects the brain and spinal ...

  5. X chromosome exome sequencing reveals a novel ALG13 mutation in a nonsyndromic intellectual disability family with multiple affected male siblings.

    PubMed

    Bissar-Tadmouri, Nesrine; Donahue, Whithey L; Al-Gazali, Lihadh; Nelson, Stanley F; Bayrak-Toydemir, Pinar; Kantarci, Sibel

    2014-01-01

    X-linked intellectual disability (XLID) is a heterogeneous condition associated with mutations in >100 genes, accounting for over 10% of all cases of intellectual impairment. The majority of XLID cases show nonsyndromic forms (NSXLID), in which intellectual disability is the sole clinically consistent manifestation. Here we performed X chromosome exome (X-exome) sequencing to identify the causative mutation in an NSXLID family with four affected male siblings and five unaffected female siblings. The X-exome sequencing at 88× coverage in one affected male sibling revealed a novel missense mutation (p.Tyr1074Cys) in the asparagine-linked glycosylation 13 homolog (ALG13) gene. Segregation analysis by Sanger sequencing showed that the all affected siblings were hemizygous and the mother was heterozygous for the mutation. Recently, a de novo missense mutation in ALG13 has been reported in a patient with X-linked congenital disorders of glycosylation type I. Our study reports the first case of NSXLID caused by a mutation in ALG13 involved in protein N-glycosylation.

  6. Fostering Autonomy through Syllabus Design: A Step-by-Step Guide for Success

    ERIC Educational Resources Information Center

    Ramírez Espinosa, Alexánder

    2016-01-01

    Promoting learner autonomy is relevant in the field of applied linguistics due to the multiple benefits it brings to the process of learning a new language. However, despite the vast array of research on how to foster autonomy in the language classroom, it is difficult to find step-by-step processes to design syllabi and curricula focused on the…

  7. One-step multiple component isolation from the oil of Crinitaria tatarica (Less.) Sojak. by preparative capillary gas with characterization by spectroscopic and spectrometric techniques and evaluation of biological activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the present work multiple component isolation from the oil of Crinitaria tatarica (Less.) Sojak. by Preparative Capillary Gas Chromatography (PCGC) with characterization by mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy have been carried out. Gas chromatography (GC-FID) ...

  8. A functional variant that affects exon-skipping and protein expression of SP140 as genetic mechanism predisposing to multiple sclerosis.

    PubMed

    Matesanz, Fuencisla; Potenciano, Victor; Fedetz, Maria; Ramos-Mozo, Priscila; Abad-Grau, María del Mar; Karaky, Mohamad; Barrionuevo, Cristina; Izquierdo, Guillermo; Ruiz-Peña, Juan Luis; García-Sánchez, María Isabel; Lucas, Miguel; Fernández, Óscar; Leyva, Laura; Otaegui, David; Muñoz-Culla, Maider; Olascoaga, Javier; Vandenbroeck, Koen; Alloza, Iraide; Astobiza, Ianire; Antigüedad, Alfredo; Villar, Luisa María; Álvarez-Cermeño, José Carlos; Malhotra, Sunny; Comabella, Manuel; Montalban, Xavier; Saiz, Albert; Blanco, Yolanda; Arroyo, Rafael; Varadé, Jezabel; Urcelay, Elena; Alcina, Antonio

    2015-10-01

    Several variants in strong linkage disequilibrium (LD) at the SP140 locus have been associated with multiple sclerosis (MS), Crohn's disease (CD) and chronic lymphocytic leukemia (CLL). To determine the causal polymorphism, we have integrated high-density data sets of expression quantitative trait loci (eQTL), using GEUVADIS RNA sequences and 1000 Genomes genotypes, with MS-risk variants of the high-density Immunochip array performed by the International Multiple Sclerosis Genetic Consortium (IMSGC). The variants most associated with MS were also correlated with a decreased expression of the full-length RNA isoform of SP140 and an increase of an isoform lacking exon 7. By exon splicing assay, we have demonstrated that the rs28445040 variant was the causal factor for skipping of exon 7. Western blots of peripheral blood mononuclear cells from MS patients showed a significant allele-dependent reduction of the SP140 protein expression. To confirm the association of this functional variant with MS and to compare it with the best-associated variant previously reported by GWAS (rs10201872), a case-control study including 4384 MS patients and 3197 controls was performed. Both variants, in strong LD (r(2) = 0.93), were found similarly associated with MS [P-values, odds ratios: 1.9E-9, OR = 1.35 (1.22-1.49) and 4.9E-10, OR = 1.37 (1.24-1.51), respectively]. In conclusion, our data uncover the causal variant for the SP140 locus and the molecular mechanism associated with MS risk. In addition, this study and others previously reported strongly suggest that this functional variant may be shared with other immune-mediated diseases as CD and CLL.

  9. Golgi-Cox Staining Step by Step

    PubMed Central

    Zaqout, Sami; Kaindl, Angela M.

    2016-01-01

    Golgi staining remains a key method to study neuronal morphology in vivo. Since most protocols delineating modifications of the original staining method lack details on critical steps, establishing this method in a laboratory can be time-consuming and frustrating. Here, we describe the Golgi-Cox staining in such detail that should turn the staining into an easily feasible method for all scientists working in the neuroscience field. PMID:27065817

  10. Nigeria: One Step Forward, Two Steps Back

    DTIC Science & Technology

    2012-11-02

    is not sustainable due to the impacts of deforestation and desertification. The Hausa-Fulani ethnic group is largely concentrated in this region...significant impact on Nigerian society, “…ultimately it is what people believe about their own identities and those of other groups that affects their social...the nation’s infrastructure has even affected the oil industry itself. All of Nigeria’s petroleum refineries are routinely offline causing

  11. Non-random autosome segregation: a stepping stone for the evolution of sex chromosome complexes? Sex-biased transmission of autosomes could facilitate the spread of antagonistic alleles, and generate sex-chromosome systems with multiple X or Y chromosomes.

    PubMed

    Schwander, Tanja; Beukeboom, Leo W

    2011-02-01

    A new study in Caenorhabditis elegans shows that homologous autosomes segregate non-randomly with the sex chromosome in the heterogametic sex. Segregation occurs according to size, small autosomes segregating with, and large autosomes segregating away from the X-chromosome. Such sex-biased transmission of autosomes could facilitate the spread of sexually antagonistic alleles whose effects favor the fitness of one sex at the expense of the other. This may provide a first step toward the evolution of new sex determination systems.

  12. The CORE study protocol: a stepped wedge cluster randomised controlled trial to test a co-design technique to optimise psychosocial recovery outcomes for people affected by mental illness in the community mental health setting

    PubMed Central

    Palmer, Victoria J; Chondros, Patty; Piper, Donella; Callander, Rosemary; Weavell, Wayne; Godbee, Kali; Potiriadis, Maria; Richard, Lauralie; Densely, Konstancja; Herrman, Helen; Furler, John; Pierce, David; Schuster, Tibor; Iedema, Rick; Gunn, Jane

    2015-01-01

    Introduction User engagement in mental health service design is heralded as integral to health systems quality and performance, but does engagement improve health outcomes? This article describes the CORE study protocol, a novel stepped wedge cluster randomised controlled trial (SWCRCT) to improve psychosocial recovery outcomes for people with severe mental illness. Methods An SWCRCT with a nested process evaluation will be conducted over nearly 4 years in Victoria, Australia. 11 teams from four mental health service providers will be randomly allocated to one of three dates 9 months apart to start the intervention. The intervention, a modified version of Mental Health Experience Co-Design (MH ECO), will be delivered to 30 service users, 30 carers and 10 staff in each cluster. Outcome data will be collected at baseline (6 months) and at completion of each intervention wave. The primary outcome is improvement in recovery score using the 24-item Revised Recovery Assessment Scale for service users. Secondary outcomes are improvements to user and carer mental health and well-being using the shortened 8-item version of the WHOQOL Quality of Life scale (EUROHIS), changes to staff attitudes using the 19-item Staff Attitudes to Recovery Scale and recovery orientation of services using the 36-item Recovery Self Assessment Scale (provider version). Intervention and usual care periods will be compared using a linear mixed effects model for continuous outcomes and a generalised linear mixed effects model for binary outcomes. Participants will be analysed in the group that the cluster was assigned to at each time point. Ethics and dissemination The University of Melbourne, Human Research Ethics Committee (1340299.3) and the Federal and State Departments of Health Committees (Project 20/2014) granted ethics approval. Baseline data results will be reported in 2015 and outcomes data in 2017. Trial registration number Australian and New Zealand Clinical Trials Registry ACTRN

  13. Information on stepping motors

    NASA Astrophysics Data System (ADS)

    Fongarland, G.

    1982-04-01

    The principles of the stepping motors which are often used in servomechanisms are reviewed. Variable reluctance as well as permanent magnet stepping motors are considered. Their operation is explained which includes permanent rotation, starting, stopping, and resonance effects. Several application examples, drawn from problems in automation, are outlined.

  14. Multiple Frequency Parametric Sonar

    DTIC Science & Technology

    2015-09-28

    300003 1 MULTIPLE FREQUENCY PARAMETRIC SONAR STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured and...beams. However, the multiple nonlinear interactions are not taken advantage of in order to generate additional efficiencies, bandwidth, and SNR...array. [0050] It will be understood that many additional changes in details, materials , steps, and arrangements of parts which have been described

  15. Inactivation of CK1α in multiple myeloma empowers drug cytotoxicity by affecting AKT and β-catenin survival signaling pathways.

    PubMed

    Manni, Sabrina; Carrino, Marilena; Manzoni, Martina; Gianesin, Ketty; Nunes, Sara Canovas; Costacurta, Matteo; Tubi, Laura Quotti; Macaccaro, Paolo; Taiana, Elisa; Cabrelle, Anna; Barilà, Gregorio; Martines, Annalisa; Zambello, Renato; Bonaldi, Laura; Trentin, Livio; Neri, Antonino; Semenzato, Gianpietro; Piazza, Francesco

    2017-01-14

    Recent evidence indicates that protein kinase CK1α may support the growth of multiple myeloma (MM) plasma cells. Here, by analyzing a large cohort of MM cases, we found that high CK1α mRNA levels are virtually associated with all MM patients. Moreover, we provided functional evidence that CK1α activity is essential for malignant plasma cell survival even in the protective niche generated by co-cultures with bone marrow stromal cells. We demonstrated that CK1α inactivation, while toxic for myeloma cells, is dispensable for the survival of healthy B lymphocytes and stromal cells. Disruption of CK1α function in myeloma cells resulted in decreased Mdm2, increased p53 and p21 and reduced expression of β-catenin and AKT. These effects were mediated partially by p53 and caspase activity. Finally, we discovered that CK1α inactivation enhanced the cytotoxic effect of both bortezomib and lenalidomide. Overall, our study supports a role for CK1α as a potential therapeutic target in MM in combination with proteasome inhibitors and/or immunomodulatory drugs.

  16. STEP Experiment Requirements

    NASA Technical Reports Server (NTRS)

    Brumfield, M. L. (Compiler)

    1984-01-01

    A plan to develop a space technology experiments platform (STEP) was examined. NASA Langley Research Center held a STEP Experiment Requirements Workshop on June 29 and 30 and July 1, 1983, at which experiment proposers were invited to present more detailed information on their experiment concept and requirements. A feasibility and preliminary definition study was conducted and the preliminary definition of STEP capabilities and experiment concepts and expected requirements for support services are presented. The preliminary definition of STEP capabilities based on detailed review of potential experiment requirements is investigated. Topics discussed include: Shuttle on-orbit dynamics; effects of the space environment on damping materials; erectable beam experiment; technology for development of very large solar array deployers; thermal energy management process experiment; photovoltaic concentrater pointing dynamics and plasma interactions; vibration isolation technology; flight tests of a synthetic aperture radar antenna with use of STEP.

  17. An allelic series of mice reveals a role for RERE in the development of multiple organs affected in chromosome 1p36 deletions.

    PubMed

    Kim, Bum Jun; Zaveri, Hitisha P; Shchelochkov, Oleg A; Yu, Zhiyin; Hernández-García, Andrés; Seymour, Michelle L; Oghalai, John S; Pereira, Fred A; Stockton, David W; Justice, Monica J; Lee, Brendan; Scott, Daryl A

    2013-01-01

    Individuals with terminal and interstitial deletions of chromosome 1p36 have a spectrum of defects that includes eye anomalies, postnatal growth deficiency, structural brain anomalies, seizures, cognitive impairment, delayed motor development, behavior problems, hearing loss, cardiovascular malformations, cardiomyopathy, and renal anomalies. The proximal 1p36 genes that contribute to these defects have not been clearly delineated. The arginine-glutamic acid dipeptide (RE) repeats gene (RERE) is located in this region and encodes a nuclear receptor coregulator that plays a critical role in embryonic development as a positive regulator of retinoic acid signaling. Rere-null mice die of cardiac failure between E9.5 and E11.5. This limits their usefulness in studying the role of RERE in the latter stages of development and into adulthood. To overcome this limitation, we created an allelic series of RERE-deficient mice using an Rere-null allele, om, and a novel hypomorphic Rere allele, eyes3 (c.578T>C, p.Val193Ala), which we identified in an N-ethyl-N-nitrosourea (ENU)-based screen for autosomal recessive phenotypes. Analyses of these mice revealed microphthalmia, postnatal growth deficiency, brain hypoplasia, decreased numbers of neuronal nuclear antigen (NeuN)-positive hippocampal neurons, hearing loss, cardiovascular malformations-aortic arch anomalies, double outlet right ventricle, and transposition of the great arteries, and perimembranous ventricular septal defects-spontaneous development of cardiac fibrosis and renal agenesis. These findings suggest that RERE plays a critical role in the development and function of multiple organs including the eye, brain, inner ear, heart and kidney. It follows that haploinsufficiency of RERE may contribute-alone or in conjunction with other genetic, environmental, or stochastic factors-to the development of many of the phenotypes seen in individuals with terminal and interstitial deletions that include the proximal region of

  18. Is environmental radon gas associated with the incidence of neurodegenerative conditions? A retrospective study of multiple sclerosis in radon affected areas in England and Wales.

    PubMed

    Groves-Kirkby, Christopher J; Denman, Antony R; Campbell, Jackie; Crockett, Robin G M; Phillips, Paul S; Rogers, Stephen

    2016-04-01

    To test whether an association exists between radon gas concentration in the home and increased multiple sclerosis (MS) incidence, a retrospective study was undertaken of MS incidence in known areas of raised domestic radon concentration in England and Wales, using The Health Improvement Network (THIN) clinical research database. The study population comprised 20,140,498 person-years of clinical monitoring (males: 10,056,628: 49.93%; females: 10,083,870: 50.07%), representing a mean annual population of 2.5 million individuals. To allow for the possible latency of MS initiation following exposure, data extraction was limited to patients with at least five years registration history with the same GP practice before first diagnosis. Patient records were allocated to one of nine radon concentration bands depending on the average radon level in their postcode sector. MS incidence was analysed by searching for patients with first MS diagnosis over the eight calendar years 2005-2012 inclusive. 1512 new MS cases were diagnosed, 1070 females, 442 males, equivalent to raw incidence rates of 7.51, 10.61 and 4.40 per 10(5) person-years respectively, comparable to previously reported results. Of these new cases, 115 could be allocated to one of the radon bands representing high radon areas. Standardising to the UK 2010 population, excess relative risk (ERR) figures for MS were calculated for each radon band. Linear regression of ERR against mean band radon concentration shows a positive gradient of 0.22 per 100 Bq·m(-3) (R(2) = 0.25, p = 0.0961) when forced through the origin to represent a linear-no-threshold response. The null hypothesis falls inside the 95% confidence interval for the linear fit and therefore this fit is not statistically significant. We conclude that, despite THIN sampling around 5% of the population, insufficient data was available to confirm or refute the hypothesised association between MS incidence and radon concentration.

  19. Impact of multiple anthropogenic stressors on freshwater: how do glyphosate and the invasive mussel Limnoperna fortunei affect microbial communities and water quality?

    PubMed

    Pizarro, Haydée; Di Fiori, Eugenia; Sinistro, Rodrigo; Ramírez, Marina; Rodríguez, Patricia; Vinocur, Alicia; Cataldo, Daniel

    2016-01-01

    The study of the joint effect of multiple anthropogenic stressors is important because the emerging consequences are often unpredictable on the basis of knowledge of single effects. We explored the joint impact of glyphosate and the invasive golden mussel Limnoperna fortunei on freshwater phytoplankton, bacterioplankton and periphyton, and on the physical and chemical properties of the water. We manipulated both stressors simultaneously in a 25-day experiment using outdoor mesocosms; we assayed technical-grade glyphosate acid at four concentrations: 0, 1, 3 and 6 mg gly L(−1) under scenarios with and without mussels. The addition of the glyphosate significantly increased total phosphorus according to the concentration used; the high clearance rate of L. fortunei significantly decreased phytoplanktonic abundance leading to low values of turbidity. The mussel significantly stimulated the development of filamentous green algae (metaphyton). Interestingly, the combined effect revealed that L. fortunei accelerated the dissipation of glyphosate, which showed a 4-fold decrease in its half-life; this promoted the rapid bioavailability of glyphosate-derived phosphorus in the water. The interaction had a synergistic effect on soluble reactive phosphorus concentrations and was directly dependent on the concentration of glyphosate. A synergistic effect was also observed on bacterioplankton, water turbidity and metaphyton, thus inducing enhanced and rapid eutrophication. The ability of mussels to reduce glyphosate in water may be valued as positive, but our results allow us to predict that the invasion of Limnoperna fortunei in natural freshwater systems contaminated by glyphosate will accelerate the negative impact of the herbicide associated with eutrophication.

  20. Detection of Steps in Single Molecule Data

    PubMed Central

    Aggarwal, Tanuj; Materassi, Donatello; Davison, Robert; Hays, Thomas; Salapaka, Murti

    2013-01-01

    Over the past few decades, single molecule investigations employing optical tweezers, AFM and TIRF microscopy have revealed that molecular behaviors are typically characterized by discrete steps or events that follow changes in protein conformation. These events, that manifest as steps or jumps, are short-lived transitions between otherwise more stable molecular states. A major limiting factor in determining the size and timing of the steps is the noise introduced by the measurement system. To address this impediment to the analysis of single molecule behaviors, step detection algorithms incorporate large records of data and provide objective analysis. However, existing algorithms are mostly based on heuristics that are not reliable and lack objectivity. Most of these step detection methods require the user to supply parameters that inform the search for steps. They work well, only when the signal to noise ratio (SNR) is high and stepping speed is low. In this report, we have developed a novel step detection method that performs an objective analysis on the data without input parameters, and based only on the noise statistics. The noise levels and characteristics can be estimated from the data providing reliable results for much smaller SNR and higher stepping speeds. An iterative learning process drives the optimization of step-size distributions for data that has unimodal step-size distribution, and produces extremely low false positive outcomes and high accuracy in finding true steps. Our novel methodology, also uniquely incorporates compensation for the smoothing affects of probe dynamics. A mechanical measurement probe typically takes a finite time to respond to step changes, and when steps occur faster than the probe response time, the sharp step transitions are smoothed out and can obscure the step events. To address probe dynamics we accept a model for the dynamic behavior of the probe and invert it to reveal the steps. No other existing method addresses

  1. Analysis of Multiple Families With Single Individuals Affected by Pseudohypoparathyroidism Type Ib (PHP1B) Reveals Only One Novel Maternally Inherited GNAS Deletion

    PubMed Central

    Takatani, Rieko; Molinaro, Angelo; Grigelioniene, Giedre; Tafaj, Olta; Watanabe, Tomoyuki; Reyes, Monica; Sharma, Amita; Singhal, Vibha; Raymond, F Lucy; Linglart, Agnès; Jüppner, Harald

    2016-01-01

    Proximal tubular resistance to parathyroid hormone (PTH) resulting in hypocalcemia and hyperphosphatemia are preeminent abnormalities in pseudohypoparathyroidism type Ib (PHP1B), but resistance toward other hormones as well as variable features of Albright’s Hereditary Osteodystrophy (AHO) can occur also. Genomic DNA from PHP1B patients shows epigenetic changes at one or multiple differentially methylated regions (DMRs) within GNAS, the gene encoding Gαs and splice variants thereof. In the autosomal dominant disease variant, these methylation abnormalities are caused by deletions in STX16 or GNAS on the maternal allele. The molecular defect(s) leading to sporadic PHP1B (sporPHP1B) remains in most cases unknown and we therefore analyzed 60 sporPHP1B patients and available family members by microsatellite markers, single nucleotide polymorphisms (SNPs), multiplex ligation-dependent probe amplification (MLPA), and methylation-specific MLPA (MS-MLPA). All investigated cases revealed broad GNAS methylation changes, but no evidence for inheritance of two paternal chromosome 20q alleles. Some patients with partial epigenetic modifications in DNA from peripheral blood cells showed more complete GNAS methylation changes when testing their immortalized lymphoblastoid cells. Analysis of siblings and children of sporPHP1B patients provided no evidence for an abnormal mineral ion regulation and no changes in GNAS methylation. Only one patient revealed, based on MLPA and microsatellite analyses, evidence for an allelic loss, which resulted in the discovery of two adjacent, maternally inherited deletions (37,597 and 1427 bp, respectively) that remove the area between GNAS antisense exons 3 and 5, including exon NESP. Our findings thus emphasize that the region comprising antisense exons 3 and 4 is required for establishing all maternal GNAS methylation imprints. The genetic defect(s) leading in sporPHP1B to epigenetic GNAS changes and thus PTH-resistance remains unknown, but

  2. The Next Giant Step

    NASA Video Gallery

    Artist Robert McCall painted "The Next Giant Step" in 1979 to commemorate the heroism and courage of spaceflight pioneers. Located in the lobby of Johnson's building 2, the mural depicts America's ...

  3. CEIP Next Steps

    EPA Pesticide Factsheets

    The Clean Energy Incentive Program (CEIP) next steps document details the EPA’s outreach strategy for stakeholder input on the design and implementation of the CEIP. Additionally, this document lists provisions on the CEIP where stakeholder input is sought

  4. Integrated Marketing for Colleges, Universities, and Schools: A Step-by-Step Planning Guide.

    ERIC Educational Resources Information Center

    Sevier, Robert A.

    This book offers a step-by-step approach to marketing for educational institutions, especially colleges and universities. The book is organized into three broad sections. Section 1 makes the case for marketing in six chapters which address: (1) challenges which are or will affect colleges and universities; (2) the role of institutional mission,…

  5. Multiple sclerosis.

    PubMed

    Files, Daniel Kane; Jausurawong, Tani; Katrajian, Ruba; Danoff, Robert

    2015-06-01

    Multiple sclerosis (MS) is a chronic, debilitating disease that can have devastating effects. Presentation varies widely in symptoms, pace, and progression. In addition to a thorough history and physical examination, diagnostic tools required to diagnose MS and exclude other diagnoses include MRI, evoked potential testing, and cerebrospinal fluid analysis. Although the disease is not curable presently, quality of life can be improved by minimizing the frequency and severity of disease burden. Disease modification, symptom management, preservation of function, and treatment of psychosocial issues are paramount to enhance the quality of life for the patient affected with MS.

  6. Dark solitons near potential and nonlinearity steps

    NASA Astrophysics Data System (ADS)

    Tsitoura, F.; Anastassi, Z. A.; Marzuola, J. L.; Kevrekidis, P. G.; Frantzeskakis, D. J.

    2016-12-01

    We study dark solitons near potential and nonlinearity steps and combinations thereof, forming rectangular barriers. This setting is relevant to the contexts of atomic Bose-Einstein condensates (where such steps can be realized by using proper external fields) and nonlinear optics (for beam propagation near interfaces separating optical media of different refractive indices). We use perturbation theory to develop an equivalent particle theory, describing the matter-wave or optical soliton dynamics as the motion of a particle in an effective potential. This Newtonian dynamical problem provides information for the soliton statics and dynamics, including scenarios of reflection, transmission, or quasitrapping at such steps. The case of multiple such steps and its connection to barrier potentials is additionally touched upon. The range of validity of the analytical approximation and radiation effects are also investigated. Our analytical predictions are found to be in very good agreement with the corresponding numerical results, where appropriate.

  7. Stepped inlet optical panel

    DOEpatents

    Veligdan, James T.

    2001-01-01

    An optical panel includes stacked optical waveguides having stepped inlet facets collectively defining an inlet face for receiving image light, and having beveled outlet faces collectively defining a display screen for displaying the image light channeled through the waveguides by internal reflection.

  8. Affects of Multiple Deployments on Families

    DTIC Science & Technology

    2009-03-11

    are faced with during lengthy deployments. “Certainly, the nature of the deployment and the role of the service member in the military action can...and sadness. Preschoolers may display regressive behavior, irritation, sadness, and aggressiveness and may have somatic complaints. School-age...may also be hesitant to be affectionate with the returned parent. Preschoolers may feel scared or angry. School-age children may crave attention from

  9. Step Prototype Development Status

    NASA Astrophysics Data System (ADS)

    Mehls, C.; Bayart, C.; Bower, J.; Clarke, B.; Cox, C.; Gill, D.; Stricker, D.; Vora, N.; Wang, S.; Zhou, P.; Torii, R.; Worden, P.; Debra, D.; Dittus, H.; Loeffler, F.

    2008-09-01

    STEP, the Satellite Test of the Equivalence Principle [1], proposes to test the Equivalence Principle to a part in 1018 by comparing the free-fall acceleration of cylindrical shaped test masses [2] in Earth orbit. Magnetic bearings constrain the test mass motion to their axis of symmetry [3]. The displacement of the test masses is measured using a DC SQUID and superconducting coils [4], enabling a displacement sensitivity as small as 10-15 m. In combination with a small spring stiffness a differential acceleration sensitivity of 10-18 g is achievable. Residual satellite acceleration is reduced to better than 10-14 g by compensating satellite drag forces with thrust provided by helium gas. We report on recent progress in the development of STEP prototype flight accelerometers, in particular the development of the high precision quartz housing for the engineering inner accelerometer and the testing of SQUID and capacitive readout systems using 'brass board' accelerometer prototypes.

  10. The digital step edge

    NASA Technical Reports Server (NTRS)

    Haralick, R. M.

    1982-01-01

    The facet model was used to accomplish step edge detection. The essence of the facet model is that any analysis made on the basis of the pixel values in some neighborhood has its final authoritative interpretation relative to the underlying grey tone intensity surface of which the neighborhood pixel values are observed noisy samples. Pixels which are part of regions have simple grey tone intensity surfaces over their areas. Pixels which have an edge in them have complex grey tone intensity surfaces over their areas. Specially, an edge moves through a pixel only if there is some point in the pixel's area having a zero crossing of the second directional derivative taken in the direction of a non-zero gradient at the pixel's center. To determine whether or not a pixel should be marked as a step edge pixel, its underlying grey tone intensity surface was estimated on the basis of the pixels in its neighborhood.

  11. Micromachine Wedge Stepping Motor

    SciTech Connect

    Allen, J.J.; Schriner, H.K.

    1998-11-04

    A wedge stepping motor, which will index a mechanism, has been designed and fabricated in the surface rnicromachine SUMMiT process. This device has demonstrated the ability to index one gear tooth at a time with speeds up to 205 teeth/see. The wedge stepper motor has the following features, whi:h will be useful in a number of applications. o The ability to precisely position mechanical components. . Simple pulse signals can be used for operation. o Only 2 drive signals are requixed for operation. o Torque and precision capabilities increase with device size . The device to be indexed is restrained at all times by the wedge shaped tooth that is used for actuation. This paper will discuss the theory of operation and desi=m of the wedge stepping motor. The fabrication and testing of I he device will also be presented.

  12. In Vitro and In Vivo Single Myosin Step-Sizes in Striated Muscle a

    PubMed Central

    Burghardt, Thomas P.; Sun, Xiaojing; Wang, Yihua; Ajtai, Katalin

    2016-01-01

    Myosin in muscle transduces ATP free energy into the mechanical work of moving actin. It has a motor domain transducer containing ATP and actin binding sites, and, mechanical elements coupling motor impulse to the myosin filament backbone providing transduction/mechanical-coupling. The mechanical coupler is a lever-arm stabilized by bound essential and regulatory light chains. The lever-arm rotates cyclically to impel bound filamentous actin. Linear actin displacement due to lever-arm rotation is the myosin step-size. A high-throughput quantum dot labeled actin in vitro motility assay (Qdot assay) measures motor step-size in the context of an ensemble of actomyosin interactions. The ensemble context imposes a constant velocity constraint for myosins interacting with one actin filament. In a cardiac myosin producing multiple step-sizes, a “second characterization” is step-frequency that adjusts longer step-size to lower frequency maintaining a linear actin velocity identical to that from a shorter step-size and higher frequency actomyosin cycle. The step-frequency characteristic involves and integrates myosin enzyme kinetics, mechanical strain, and other ensemble affected characteristics. The high-throughput Qdot assay suits a new paradigm calling for wide surveillance of the vast number of disease or aging relevant myosin isoforms that contrasts with the alternative model calling for exhaustive research on a tiny subset myosin forms. The zebrafish embryo assay (Z assay) performs single myosin step-size and step-frequency assaying in vivo combining single myosin mechanical and whole muscle physiological characterizations in one model organism. The Qdot and Z assays cover “bottom-up” and “top-down” assaying of myosin characteristics. PMID:26728749

  13. Stepping up with Pedometers

    ERIC Educational Resources Information Center

    Cagle, Bart

    2004-01-01

    Physical educators are using technology more than ever to help meet the national standards in physical education. One of the more useful technological tools is the digital pedometer. The newer versions of pedometers have multiple functions. They record the time elapsed, distance traveled and speed, and pulse rate. Others are equipped with a melody…

  14. Step proof mass dynamics

    NASA Astrophysics Data System (ADS)

    Wiegand, M.; Scheithauer, S.; Theil, S.

    2004-05-01

    The Satellite Test of Equivalence Principle (STEP) is a joint European-US project to investigate one of the most fundamental principles in physics, the Equivalence of inertia and passive gravitational mass. As STEP matures into a flight program, the development of a precise spacecraft dynamics simulator becomes crucial. The simulator is primarily needed for design, test and verification of the drag-free control (DFC) system and the flight software. The drag-free concept involves centering the proof mass located inside a satellite. As the proof mass is free of external disturbances (drag free), it follows a purely gravitational orbit. Since the satellite is forced to follow the proof mass, it too follows the same gravitational orbit, canceling all non-gravitational forces. For the STEP Mission, the DFC system is required to attenuate any disturbance forces acting on the spacecraft to achieve residual acceleration at location of the accelerometer of less than 3×10 -14 m/s2 (rms) across the measurement bandwidth. While the simulator is based on a high-fidelity six-degree-of-freedom numerical simulation, a simplified model is used to analyze the proof mass dynamics. The stability analysis of the proof mass motion is performed by transformation of the simplified model into the standard form of the Mathieu differential equation. The stability regions of the solution are applied to choose proper values for parameters like coupling forces between satellite and proof mass as a function of spacecraft rotation. The paper describes the calculation of the spacecraft/payload dynamics and the assumptions used to derive the underlying algorithms with a special emphasis on numerical precision issues.

  15. New photolithography stepping machine

    SciTech Connect

    Hale, L.; Klingmann, J.; Markle, D.

    1995-03-08

    A joint development project to design a new photolithography steeping machine capable of 150 nanometer overlay accuracy was completed by Ultratech Stepper and the Lawrence Livermore National Laboratory. The principal result of the project is a next-generation product that will strengthen the US position in step-and-repeat photolithography. The significant challenges addressed and solved in the project are the subject of this report. Design methods and new devices that have broader application to precision machine design are presented in greater detail while project specific information serves primarily as background and motivation.

  16. Steps to the moon

    USGS Publications Warehouse

    ,; Dale, Alvin E.

    1976-01-01

    On July 20, 1969, man walked on the surface of the Moon and began a new chapter of his studies that will eventually disclose the geologic nature of the Earth's nearest neighbor. Although he has finally reached the Moon and sampled its substance, much work and study remain before he will know the full scientific significance of the first landing. This booklet briefly summarizes the steps man has taken to understand the Moon and what he thinks he has learned to date as a result of his centuries-long speculations and studies.

  17. A Reconfigurable Stepping Motor

    NASA Astrophysics Data System (ADS)

    Rogers, Charles; Selvaggi, Richard

    2009-04-01

    Multiphase brushless actuators, commonly known as the stepper motors, are ubiquitous for many precision control applications. Developments in the microelectronics have lead to their use as efficient drive motors for modern electric vehicles. Understanding the physics and the control logic for interfacing these transducers continues to be important for scientists and engineers. An overview of the stepping motor principles and interfacing requirements is presented and a simple working model used to teach the concepts of stepper motors is described and demonstrated. This model was used to design a much larger stepper motor required to precisely rotate a massive optical system in the undergraduate advanced physics laboratory.

  18. SPAR-H Step-by-Step Guidance

    SciTech Connect

    W. J. Galyean; A. M. Whaley; D. L. Kelly; R. L. Boring

    2011-05-01

    This guide provides step-by-step guidance on the use of the SPAR-H method for quantifying Human Failure Events (HFEs). This guide is intended to be used with the worksheets provided in: 'The SPAR-H Human Reliability Analysis Method,' NUREG/CR-6883, dated August 2005. Each step in the process of producing a Human Error Probability (HEP) is discussed. These steps are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff. The discussions on dependence are extensive and include an appendix that describes insights obtained from the psychology literature.

  19. Multiple steps control immunity during the intracellular accommodation of rhizobia

    PubMed Central

    Berrabah, Fathi; Ratet, Pascal; Gourion, Benjamin

    2015-01-01

    Medicago truncatula belongs to the legume family and forms symbiotic associations with nitrogen fixing bacteria, the rhizobia. During these interactions, the plants develop root nodules in which bacteria invade the plant cells and fix nitrogen for the benefit of the plant. Despite massive infection, legume nodules do not develop visible defence reactions, suggesting a special immune status of these organs. Some factors influencing rhizobium maintenance within the plant cells have been previously identified, such as the M. truncatula NCR peptides whose toxic effects are reduced by the bacterial protein BacA. In addition, DNF2, SymCRK, and RSD are M. truncatula genes required to avoid rhizobial death within the symbiotic cells. DNF2 and SymCRK are essential to prevent defence-like reactions in nodules after bacteria internalization into the symbiotic cells. Herein, we used a combination of genetics, histology and molecular biology approaches to investigate the relationship between the factors preventing bacterial death in the nodule cells. We show that the RSD gene is also required to repress plant defences in nodules. Upon inoculation with the bacA mutant, defence responses are observed only in the dnf2 mutant and not in the symCRK and rsd mutants. In addition, our data suggest that lack of nitrogen fixation by the bacterial partner triggers bacterial death in nodule cells after bacteroid differentiation. Together our data indicate that, after internalization, at least four independent mechanisms prevent bacterial death in the plant cell. These mechanisms involve successively: DNF2, BacA, SymCRK/RSD and bacterial ability to fix nitrogen. PMID:25682610

  20. Vision and multiple sclerosis.

    PubMed

    Hickman, Simon J; Raoof, Naz; McLean, Rebecca J; Gottlob, Irene

    2014-01-01

    Multiple sclerosis can affect vision in many ways, including optic neuritis, chronic optic neuropathy, retrochiasmal visual field defects, higher order cortical processing, double vision, nystagmus and also by related ocular conditions such as uveitis. There are also side effects from recently introduced multiple sclerosis treatments that can affect vision. This review will discuss all these aspects and how they come together to cause visual symptoms. It will then focus on practical aspects of how to recognise when there is a vision problem in a multiple sclerosis patient and on what treatments are available to improve vision.

  1. Stair-stepped Mound

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-429, 22 July 2003

    This April 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a stair-stepped mound of sedimentary rock (right of center) on the floor of a large impact crater in western Arabia Terra near 11.0oN, 4.4oW. Sedimentary rock outcrops are common in the craters of this region. The repeated thickness and uniformity of the layers that make up this mound suggest that their depositional environment was one in which cyclic or episodic events occurred over some period of time. The sediments might have been deposited in a lake, or they may have settled directly out of the atmosphere. Most of the layered material was later eroded away, leaving this circular mound and the other nearby mesas and knobs. The image is illuminated by sunlight from the lower left.

  2. Estimating V0[subscript 2]max Using a Personalized Step Test

    ERIC Educational Resources Information Center

    Webb, Carrie; Vehrs, Pat R.; George, James D.; Hager, Ronald

    2014-01-01

    The purpose of this study was to develop a step test with a personalized step rate and step height to predict cardiorespiratory fitness in 80 college-aged males and females using the self-reported perceived functional ability scale and data collected during the step test. Multiple linear regression analysis yielded a model (R = 0.90, SEE = 3.43…

  3. Green Schools Energy Project: A Step-by-Step Manual.

    ERIC Educational Resources Information Center

    Quigley, Gwen

    This publication contains a step-by-step guide for implementing an energy-saving project in local school districts: the installation of newer, more energy-efficient "T-8" fluorescent tube lights in place of "T-12" lights. Eleven steps are explained in detail: (1) find out what kind of lights the school district currently uses;…

  4. Multiplication Fact Fluency Using Doubles

    ERIC Educational Resources Information Center

    Flowers, Judith M.; Rubenstein, Rheta N.

    2010-01-01

    Not knowing multiplication facts creates a gap in a student's mathematics development and undermines confidence and disposition toward further mathematical learning. Learning multiplication facts is a first step in proportional reasoning, "the capstone of elementary arithmetic and the gateway to higher mathematics" (NRC 2001, p. 242). Proportional…

  5. One-step microlithography

    NASA Astrophysics Data System (ADS)

    Kahlen, Franz-Josef; Sankaranarayanan, Srikanth; Kar, Aravinda

    1997-09-01

    Subject of this investigation is a one-step rapid machining process to create miniaturized 3D parts, using the original sample material. An experimental setup where metal powder is fed to the laser beam-material interaction region has been built. The powder is melted and forms planar, 2D geometries as the substrate is moved under the laser beam in XY- direction. After completing the geometry in the plane, the substrate is displaced in Z-direction, and a new layer of material is placed on top of the just completed deposit. By continuous repetition of this process, 3D parts wee created. In particular, the impact of the focal spot size of the high power laser beam on the smallest achievable structures was investigated. At a translation speed of 51 mm/s a minimum material thickness of 590 micrometers was achieved. Also, it was shown that a small Z-displacement has a negligible influence on the continuity of the material deposition over this power range. A high power CO2 laser was used as energy source, the material powder under investigation was stainless steel SS304L. Helium was used as shield gas at a flow rate of 15 1/min. The incident CO2 laser beam power was varied between 300 W and 400 W, with the laser beam intensity distribute in a donut mode. The laser beam was focused to a focal diameter of 600 (Mu) m.

  6. The Stepping Stone Approach

    NASA Astrophysics Data System (ADS)

    Brumfitt, A.

    Education is a profession in its own right. It has its own parameters, passions and language. Having the responsibility both of educare and educere, education has a focus of delivering specific factual knowledge whilst drawing out the creative mind. Space Science is a special vehicle having the properties of both educare and educere. It has a magic and wonder that touches the very essence of an individual and his place in time and space; it offers the "wow" factor that all teachers strive for. Space Science is the wrapping paper for other elements in the curriculum, e.g. cross-curricula and skill-based activities, such as language development, creativity, etc. as well as the pure sciences which comprise of engineering, physics and other natural sciences from astronomy to chemistry to biology. Each of these spheres of influence are relevant from kindergarten to undergraduate studies and complement, and in addition support informal education in museums, science centers and the world of e-learning. ESA Science Education has devised the "Stepping Stone Approach" to maximize the greatest outreach to all education stakeholders in Europe. In this paper we illustrate how to best reach these target groups with very specific activities to trigger and sustain enthusiasm whilst supporting the pedagogical, subject content and skill-based needs of a prescribed curriculum.

  7. 1992 STEP Symposium

    NASA Astrophysics Data System (ADS)

    Lui, Tony

    The year 1992 marks the quincentenary jubilee of the famous voyage of Christopher Columbus to the New World, a trip which initiated sustained contact between Europe and the American continent. Courageous explorations often lead to advancement of mankind, be they in uncharted territory or science. As much as Columbus was unaware of what lay in store for his voyage, we were just as poorly informed about what lay beyond our home planet when we began space exploration about three decades ago. There is much similarity among the pioneering spirits characteristic of both endeavors. It is thus fitting to celebrate this quincentenary occasion by declaring 1992 International Space Year (ISY).In conjunction with the COSPAR Meeting and the International Convention of the World Space Congress to be held in Washington, D.C., from August to September 1992, a 4-day symposium on the initial results from the Solar-Terrestrial Energy Program (STEP) Facilities and Theory Campaigns will be held at Johns Hopkins University, Applied Physics Laboratory, Laurel, Md., August 24-27. 1992.

  8. Developing Effective Affective Assessment Practices

    ERIC Educational Resources Information Center

    Glennon, William; Hart, Aaron; Foley, John T.

    2015-01-01

    Physical educators generally understand the importance of the affective domain for student growth and development. However, many teachers struggle with assessing affective behaviors in a way that can be documented and reported. The five-step process outlined in this article can assist teachers in developing an effective way to assess the affective…

  9. STEPS: JPL's Astrometric Exoplanet Survey

    NASA Technical Reports Server (NTRS)

    Shaklan, Stuart; Pravdo, Steve

    2008-01-01

    Presentation topics include: STEPS ground-based astrometry at Hale Telescope; the instrument; why astronomy and why M-dwarfs; motion of center of light about center of mass in photocentric orbit; photocentric motion vs. fractional mass; high-resolution imaging of STEPS targets; GU 802 p one possible orbit plotted with data, Keplerian frame; GJ 802 results; STEPS future; and a bibliography of STEPS papers.

  10. SPAR-H Step-by-Step Guidance

    SciTech Connect

    April M. Whaley; Dana L. Kelly; Ronald L. Boring; William J. Galyean

    2012-06-01

    Step-by-step guidance was developed recently at Idaho National Laboratory for the US Nuclear Regulatory Commission on the use of the Standardized Plant Analysis Risk-Human Reliability Analysis (SPAR-H) method for quantifying Human Failure Events (HFEs). This work was done to address SPAR-H user needs, specifically requests for additional guidance on the proper application of various aspects of the methodology. This paper overviews the steps of the SPAR-H analysis process and highlights some of the most important insights gained during the development of the step-by-step directions. This supplemental guidance for analysts is applicable when plant-specific information is available, and goes beyond the general guidance provided in existing SPAR-H documentation. The steps highlighted in this paper are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff.

  11. Powerlessness Reinterpreted: Reframing Step One.

    ERIC Educational Resources Information Center

    Young, Susan L.

    The 12 steps of the well-known mutual help group, Alcoholics Anonymous (AA), begin with Step One, admitting powerlessness. Although Step One has helped many problem drinkers and other addicts, its spiritual concepts have been criticized. The possibility of reconceptualizing powerlessness as empowering, not only within AA and its offshoot programs,…

  12. Early invitation to food and/or multiple micronutrient supplementation in pregnancy does not affect body composition in offspring at 54 months: follow-up of the MINIMat randomised trial, Bangladesh.

    PubMed

    Khan, Ashraful Islam; Kabir, Iqbal; Hawkesworth, Sophie; Ekström, Eva-Charlotte; Arifeen, Shams; Frongillo, Edward A; Persson, Lars Åke

    2015-07-01

    Growth patterns in early life are associated with later health. The effect of nutrition during in utero development on later body composition is unclear. We evaluated whether prenatal early invitation to food and/or multiple micronutrient supplementation (MMS) in pregnancy has an effect on offspring body composition at 54 months of age. In Maternal and Infant Nutrition Interventions in Matlab trial (ISRCTN16581394) in Bangladesh, 4436 pregnant women were randomised into six equally sized groups: double-masked supplementation with capsules of either 30 mg Fe and 400 μg folic acid, or 60 mg Fe and 400 μg folic acid, or MMS (15 micronutrients), was combined with a randomised early invitation (around 9 weeks) or a usual invitation (around 20 weeks) to start food supplementation (608 kcal 6 days per week). At 54 months, the body composition of the offspring was assessed by leg-to-leg bioelectrical impedance analysis. Of the 3267 live singletons with birth anthropometry, 2290 children were measured at 54 months, representing 70% of the live births. There was no interaction between the food and micronutrient supplementation on body composition outcomes. There were no significant differences in a range of anthropometric and body composition measurements, including weight, height, mid-upper arm circumference, head circumference, skinfold thickness, and fat mass and fat-free mass between the different prenatal food and micronutrient groups using an intention-to-treat analysis. This analysis shows that early invitation to food supplementation and MMS provided to rural Bangladeshi women during pregnancy did not affect offspring body composition at 54 months of age.

  13. Multiple osteochondromas

    PubMed Central

    Bovée, Judith VMG

    2008-01-01

    Multiple osteochondromas (MO) is characterised by development of two or more cartilage capped bony outgrowths (osteochondromas) of the long bones. The prevalence is estimated at 1:50,000, and it seems to be higher in males (male-to-female ratio 1.5:1). Osteochondromas develop and increase in size in the first decade of life, ceasing to grow when the growth plates close at puberty. They are pedunculated or sessile (broad base) and can vary widely in size. The number of osteochondromas may vary significantly within and between families, the mean number of locations is 15–18. The majority are asymptomatic and located in bones that develop from cartilage, especially the long bones of the extremities, predominantly around the knee. The facial bones are not affected. Osteochondromas may cause pain, functional problems and deformities, especially of the forearm, that may be reason for surgical removal. The most important complication is malignant transformation of osteochondroma towards secondary peripheral chondrosarcoma, which is estimated to occur in 0.5–5%. MO is an autosomal dominant disorder and is genetically heterogeneous. In almost 90% of MO patients germline mutations in the tumour suppressor genes EXT1 or EXT2 are found. The EXT genes encode glycosyltransferases, catalyzing heparan sulphate polymerization. The diagnosis is based on radiological and clinical documentation, supplemented with, if available, histological evaluation of osteochondromas. If the exact mutation is known antenatal diagnosis is technically possible. MO should be distinguished from metachondromatosis, dysplasia epiphysealis hemimelica and Ollier disease. Osteochondromas are benign lesions and do not affect life expectancy. Management includes removal of osteochondromas when they give complaints. Removed osteochondromas should be examined for malignant transformation towards secondary peripheral chondrosarcoma. Patients should be well instructed and regular follow-up for early detection

  14. When a Step Is Not a Step! Specificity Analysis of Five Physical Activity Monitors

    PubMed Central

    O’Connell, Sandra; ÓLaighin, Gearóid

    2017-01-01

    authors conclude that non-stepping physical activities can result in the false detection of steps. This can negatively affect the quantification of physical activity with regard to step count as an output. The Withings™ activity monitor performed best with regard to specificity during the activities of daily living tested. PMID:28085918

  15. Multiple Sclerosis

    MedlinePlus

    Multiple sclerosis Overview By Mayo Clinic Staff Multiple sclerosis (MS) is a potentially disabling disease of the brain and spinal cord (central nervous system). In MS, the immune system attacks the protective ...

  16. Multiple myeloma

    MedlinePlus

    Plasma cell dyscrasia; Plasma cell myeloma; Malignant plasmacytoma; Plasmacytoma of bone; Myeloma - multiple ... Multiple myeloma most commonly causes: Low red blood cell count ( anemia ), which can lead to fatigue and ...

  17. Multiple pterygium syndrome.

    PubMed Central

    Penchaszadeh, V B; Salszberg, B

    1981-01-01

    The multiple pterygium syndrome is a rare autosomal recessive condition characterised by arthrogryposis multiplex congenita, pterygia of the neck, fingers, and antecubital, popliteal, and intercrural areas, growth retardation, and facial, vertebral, and genital anomalies. We present two unrelated patients of 17 and 6 years of age, respectively, affected with this condition. We describe the natural history of their disorder since birth and review the spectrum of phenotypic variation of the multiple pterygium syndrome in 25 published cases. Images PMID:7334504

  18. Step-gradient capillary electrochromatography.

    PubMed

    Euerby, M R; Gilligan, D; Johnson, C M; Bartle, K D

    1997-10-01

    The analytical benefits of using a step-gradient in capillary electrochromatography (CEC) are demonstrated. The application of step-gradient CEC to the analysis of six diuretics of widely differing lipophilicities was evaluated and shown to result in a marked reduction in the analysis time and an improvement in the peak shape for later-eluting lipophilic components. When the step-gradient approach was performed in an automated mode, the retention time RSD for repeated injections was below 1%.

  19. Multiplicity Counting

    SciTech Connect

    Geist, William H.

    2015-12-01

    This set of slides begins by giving background and a review of neutron counting; three attributes of a verification item are discussed: 240Pueff mass; α, the ratio of (α,n) neutrons to spontaneous fission neutrons; and leakage multiplication. It then takes up neutron detector systems – theory & concepts (coincidence counting, moderation, die-away time); detector systems – some important details (deadtime, corrections); introduction to multiplicity counting; multiplicity electronics and example distributions; singles, doubles, and triples from measured multiplicity distributions; and the point model: multiplicity mathematics.

  20. Step by Step to Smoke-Free Schools.

    ERIC Educational Resources Information Center

    VanSciver, James H.; Roberts, H. Earl

    1989-01-01

    This ERIC digest discusses ways of effectively banning smoking in schools so that controversies do not continue after implementation of the policy. By advocating a process approach, the document cites steps taken by the Lake Forest School Board to prohibit smoking in and around school grounds. Step one involved committee planning involving…

  1. Step-by-Step Visual Manuals: Design and Development

    ERIC Educational Resources Information Center

    Urata, Toshiyuki

    2004-01-01

    The types of handouts and manuals that are used in technology training vary. Some describe procedures in a narrative way without graphics; some employ step-by-step instructions with screen captures. According to Thirlway (1994), a training manual should be like a tutor that permits a student to learn at his own pace and gives him confidence for…

  2. Preface, Soil Science: A step-by-step analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book provides step-by-step procedures for soil professionals, without a lot of background theory. Chapters are targeted toward agricultural and environmental consultants, producers, students, teachers, government, and industry. Applied soil scientists gave input through a survey, which guided t...

  3. Leading Change Step-by-Step: Tactics, Tools, and Tales

    ERIC Educational Resources Information Center

    Spiro, Jody

    2010-01-01

    "Leading Change Step-by-Step" offers a comprehensive and tactical guide for change leaders. Spiro's approach has been field-tested for more than a decade and proven effective in a wide variety of public sector organizations including K-12 schools, universities, international agencies and non-profits. The book is filled with proven tactics for…

  4. [Emotions and affect in psychoanalysisis].

    PubMed

    Carton, Solange; Widlöcher, Daniel

    2012-06-01

    The goal of this paper is to give some indications on the concept of affect in psychoanalysis. There is no single theory of affect, and Freud gave successive definitions, which continue to be deepened in contemporary psychoanalysis. We review some steps of Freud works on affect, then we look into some present major questions, such as its relationship to soma, the nature of unconscious affects and the repression of affect, which is particularly developed in the field of psychoanalytic psychosomatic. From Freud's definitions of affect as one of the drive representative and as a limit-concept between the somatic and the psychic, we develop some major theoretical perspectives, which give a central place to soma and drive impulses, and which agree on the major idea that affect is the result of a process. We then note some parallelism between psychoanalysis of affect and psychology and neurosciences of emotion, and underline the gaps and conditions of comparison between these different epistemological approaches.

  5. Nonradiative Step Facets in Semiconductor Nanowires.

    PubMed

    Sanchez, Ana M; Zhang, Yunyan; Tait, Edward W; Hine, Nicholas D M; Liu, Huiyun; Beanland, Richard

    2017-04-12

    One of the main advantages of nanowires for functional applications is their high perfection, which results from surface image forces that act on line defects such as dislocations, rendering them unstable and driving them out of the crystal. Here we show that there is a class of step facets that are stable in nanowires, with no long-range strain field or dislocation character. In zinc-blende semiconductors, they take the form of Σ3 (112) facets with heights constrained to be a multiple of three {111} monolayers. Density functional theory calculations show that they act as nonradiative recombination centers and have deleterious effects on nanowire properties. We present experimental observations of these defects on twin boundaries and twins that terminate inside GaAsP nanowires and find that they are indeed always multiples of three monolayers in height. Strategies to use the three-monolayer rule during growth to prevent their formation are discussed.

  6. 6 Steps to a Solution.

    ERIC Educational Resources Information Center

    LeTendre, Brenda Guenther

    2000-01-01

    Getting answers to questions about schools and student learning requires that educators know how to collect, analyze, and interpret data. Six critical steps in this process include: posing questions, establishing judgment criteria, making a plan, gathering data, analyzing data, and interpreting results. These steps can serve as a beginning guide…

  7. Physical modeling of stepped spillways

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stepped spillways applied to embankment dams are becoming popular for addressing the rehabilitation of aging watershed dams, especially those situated in the urban landscape. Stepped spillways are typically placed over the existing embankment, which provides for minimal disturbance to the original ...

  8. Luminosity progression in dart-stepped leader step formation

    NASA Astrophysics Data System (ADS)

    Wang, D.; Takagi, N.; Uman, M. A.; Jordan, D. M.

    2016-12-01

    Using a high-speed optical imaging system, we have observed the step formation bright pulse discharges occurring at the tip of dart-stepped leaders of rocket triggered lightning with a time resolution of 0.1 µs and a spatial resolution of about 1.4 m. Each of the step formation pulse discharges appeared to initiate at a location immediately below the bottom of its previous pulse discharge and to propagate in bidirectional (upward and downward) waves with a speed on the order of 107 m/s. The downward waves of the pulse discharges tended to slow down significantly after they propagated a distance of about 2 m. Based on the results observed in this study and those published in literatures, we propose a conceptual view of leader step formation.

  9. 48 CFR 52.214-24 - Multiple Technical Proposals.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Multiple Technical....214-24 Multiple Technical Proposals. As prescribed in 14.201-6(s), insert the following provision: Multiple Technical Proposals (APR 1984) In the first step of this two-step acquisition, solicited...

  10. Enhancing multiple disciplinary teamwork.

    PubMed

    Weaver, Terri E

    2008-01-01

    Multiple disciplinary research provides an opportunity to bring together investigators across disciplines to provide new views and develop innovative approaches to important questions. Through this shared experience, novel paradigms are formed, original frameworks are developed, and new language is generated. Integral to the successful construction of effective cross-disciplinary teams is the recognition of antecedent factors that affect the development of the team such as intrapersonal, social, physical environmental, organizational, and institutional influences. Team functioning is enhanced with well-developed behavioral, affective, interpersonal, and intellectual processes. Outcomes of effective multiple disciplinary research teams include novel ideas, integrative models, new training programs, institutional change, and innovative policies that can also influence the degree to which antecedents and processes contribute to team performance. Ongoing evaluation of team functioning and achievement of designated outcomes ensures the continued development of the multiple disciplinary team and confirmation of this approach as important to the advancement of science.

  11. The NIST Step Class Library (Step Into the Future)

    DTIC Science & Technology

    1990-09-01

    Katherine C. Morris (kc@cme.nist.gov) Factory Automation System Division National Institute of Standards and Technology "Any meaningful exchange of...Industrial Automation Systems (1C 184) Subcommittee on Manufacturing Data and Languages (SC4).[NCGA90] [Smith89] 2. The Omnibus Trade Act of 1988 changed the...Figure 6. Excerpt from a STEP exclange file based on the Geometry model 1be NIST STEP Class Libary Page 13 An issue of concern in this

  12. Step-by-step growth of complex oxide microstructures

    SciTech Connect

    Datskos, Panos G.; Cullen, David A.; Sharma, Jaswinder K.

    2015-06-10

    The synthesis of complex and hybrid oxide microstructures is of fundamental interest and practical applications. However, the design and synthesis of such structures is a challenging task. We developed a solution phase process to synthesize complex silica and silica titania hybrid microstructures by exploiting the emulsion droplet based shape control and step by step growth. The strategy is robust and can be extended to make complex hybrid structures made of two or more materials while each having its own shape.

  13. Gene and library synthesis without amplification: polymerase step reaction (PSR).

    PubMed

    Lee, Zhuo-Bin; Firnhaber, Christopher; Clarke, Jesse; DeDecker, Brian S

    2015-09-01

    Current gene synthesis methods often incorporate a PCR amplification step in order to yield final material sufficient for resolution from multiple off-products. These amplification steps can cause stochastic sampling effects that propagate errors in gene synthesis or decrease variability when applied to the construction of randomized libraries. We have developed a simple DNA polymerase-based gene synthesis reaction, polymerase step reaction (PSR), that assembles DNA oligonucleotides in a unidirectional fashion without the need for amplification. We demonstrate that PSR is efficient, with little off-product production, no detectable error propagation, and maximized variability in the synthesis of a phage display library.

  14. Multiple myeloma.

    PubMed

    Peller, Patrick J

    2015-04-01

    This article presents a review of multiple myeloma, precursor states, and related plasma cell disorders. The clinical roles of fluorodeoxyglucose PET/computed tomography (CT) and the potential to improve the management of patients with multiple myeloma are discussed. The clinical and research data supporting the utility of PET/CT use in evaluating myeloma and other plasma cell dyscrasias continues to grow.

  15. 7 Steps to Aging Well

    MedlinePlus

    ... Issue Past Issues Special Section 7 Steps to Aging Well Past Issues / Winter 2007 Table of Contents ... Exercise: A Guide from the National Institute on Aging is a publication from NIA that has strength, ...

  16. In vitro models of multiple system atrophy.

    PubMed

    Stefanova, Nadia; Reindl, Markus; Poewe, Werner; Wenning, Gregor K

    2005-08-01

    alpha-Synuclein represents the major constituent of oligodendroglial cytoplasmic inclusions, the hallmark lesion of multiple system atrophy (MSA), a progressive disorder that is associated with selective degenerative cell loss in basal ganglia, cerebellum, brainstem, and spinal cord. The role of abnormal alpha-synuclein aggregation in oligodendroglial cells is still obscure, in particular, whether alpha-synuclein might impair oligodendroglial and, secondarily, neuronal integrity of those cells in the diseased brain. In an attempt to answer some of these questions, we have developed an "in vitro model of MSA" by expressing the wild-type or C-terminally truncated form of alpha-synuclein in glial cell cultures. With this simplified system, we have demonstrated that alpha-synuclein significantly affects the survival of glia and its vulnerability to environmental stress, which might represent a major step in the pathogenesis of MSA.

  17. Atomic friction at exposed and buried graphite step edges: Experiments and simulations

    SciTech Connect

    Ye, Zhijiang; Martini, Ashlie

    2015-06-08

    The surfaces of layered materials such as graphite exhibit step edges that affect friction. Step edges can be exposed, where the step occurs at the outmost layer, or buried, where the step is underneath another layer of material. Here, we study friction at exposed and buried step edges on graphite using an atomic force microscope (AFM) and complementary molecular dynamics simulations of the AFM tip apex. Exposed and buried steps exhibit distinct friction behavior, and the friction on either step is affected by the direction of sliding, i.e., moving up or down the step, and the bluntness of the tip. These trends are analyzing in terms of the trajectory of the AFM tip as it moves over the step, which is a convolution of the topography of the surface and the tip shape.

  18. Parenting Multiples

    MedlinePlus

    ... parents. It's important for caretakers to spend time speaking directly to each child, as well as reading to them and encouraging language. Social skills can come earlier for multiples, simply because they' ...

  19. Optimizing step gauge measurements and uncertainties estimation

    NASA Astrophysics Data System (ADS)

    Hennebelle, F.; Coorevits, T.; Vincent, R.

    2017-02-01

    According to the standard ISO 10360-2 (2001 Geometrical product specifications (GPS)—acceptance and reverification tests for coordinate measuring machines (CMM)—part 2: CMMs used for measuring size (ISO 10360-2:2001)), we verify the coordinate measuring machine (CMM) performance against the manufacturer specification. There are many types of gauges used for the calibration and verification of CMMs. The step gauges with parallel faces (KOBA, MITUTOYO) are well known gauges to perform this test. Often with these gauges, only the unidirectional measurements are considered which avoids having to deal with a residual error that affects the tip radius compensation. However the ISO 10360-2 standard imposes the use of a bidirectional measurement. Thus, the bidirectional measures must be corrected by the residual constant offset probe. In this paper, we optimize the step gauge measurement and a method is given to mathematically avoid the problem of the constant offset of the tip radius. This method involves measuring the step gauge once and to measure it a second time with a shift of one slot in order to obtain a new set of equations. Uncertainties are also presented.

  20. A step-by-step methodology for enterprise interoperability projects

    NASA Astrophysics Data System (ADS)

    Chalmeta, Ricardo; Pazos, Verónica

    2015-05-01

    Enterprise interoperability is one of the key factors for enhancing enterprise competitiveness. Achieving enterprise interoperability is an extremely complex process which involves different technological, human and organisational elements. In this paper we present a framework to help enterprise interoperability. The framework has been developed taking into account the three domains of interoperability: Enterprise Modelling, Architecture and Platform and Ontologies. The main novelty of the framework in comparison to existing ones is that it includes a step-by-step methodology that explains how to carry out an enterprise interoperability project taking into account different interoperability views, like business, process, human resources, technology, knowledge and semantics.

  1. Writing a Simulation Scenario: A Step-By-Step Guide.

    PubMed

    Bambini, Deborah

    2016-02-01

    Simulation is becoming a widely used method of helping nurses learn and maintain competency in the clinical area for both staff educators in clinical settings and nursing faculty in academic settings. Designing an effective simulation experience requires thoughtful planning, knowledge of educational principles, and knowledge of best practices in both simulation and clinical practice. An evidence-based strategy for writing a simulation scenario for nurses and other health care providers in any setting is described. A step-by-step process is outlined that incorporates best practices. Examples and suggestions are provided to help readers create quality simulation experiences.

  2. Partial Return Yoke for MICE Step IV and Final Step

    SciTech Connect

    Witte, Holger; Plate, Stephen; Berg, J.Scott; Tarrant, Jason; Bross, Alan

    2015-06-01

    This paper reports on the progress of the design and construction of a retro-fitted return yoke for the international Muon Ionization Cooling Experiment (MICE). MICE is a proof-of-principle experiment aiming to demonstrate ionization cooling experimentally. In earlier studies we outlined how a partial return yoke can be used to mitigate stray magnetic field in the experimental hall; we report on the progress of the construction of the partial return yoke for MICE Step IV. We also discuss an extension of the Partial Return Yoke for the final step of MICE; we show simulation results of the expected performance.

  3. Stutter-Step Models of Performance in School

    ERIC Educational Resources Information Center

    Morgan, Stephen L.; Leenman, Theodore S.; Todd, Jennifer J.; Kentucky; Weeden, Kim A.

    2013-01-01

    To evaluate a stutter-step model of academic performance in high school, this article adopts a unique measure of the beliefs of 12,591 high school sophomores from the Education Longitudinal Study, 2002-2006. Verbatim responses to questions on occupational plans are coded to capture specific job titles, the listing of multiple jobs, and the listing…

  4. [Affective dependency].

    PubMed

    Scantamburlo, G; Pitchot, W; Ansseau, M

    2013-01-01

    Affective dependency is characterized by emotional distress (insecure attachment) and dependency to another person with a low self-esteem and reassurance need. The paper proposes a reflection on the definition of emotional dependency and the confusion caused by various denominations. Overprotective and authoritarian parenting, cultural and socio-environmental factors may contribute to the development of dependent personality. Psychological epigenetic factors, such as early socio-emotional trauma could on neuronal circuits in prefronto-limbic regions that are essential for emotional behaviour.We also focus on the interrelations between dependent personality, domestic violence and addictions. The objective for the clinician is to propose a restoration of self-esteem and therapeutic strategies focused on autonomy.

  5. Multiple Endocrine Neoplasia Syndromes

    PubMed Central

    Pont, Allan

    1980-01-01

    The multiple endocrine neoplasia (MEN) syndromes consist of three distinct disease entities. They have in common adenomatous, carcinomatous or hyperplastic involvement of a variety of endocrine glands, and an autosomal dominant inheritance. MEN I includes hyperparathyroidism, islet cell and pituitary tumors. The components of MEN IIa are hyperparathyroidism, medullary thyroid carcinoma and pheochromocytoma. MEN IIb includes multiple neuromas, medullary thyroid carcinoma and pheochromocytoma. Effective tests are available for the early detection of components of the syndromes in potentially affected patients. Screening can lead to therapeutic intervention before clinical sequelae ensue. PMID:6247851

  6. Diagnostic Failure: A Cognitive and Affective Approach

    DTIC Science & Technology

    2005-01-01

    cognitive ills.”59 Principle among them is the strategy of metacognition . This involves being able to step back from the immediate pull of the situation to...ability to disengage, reflect, and reconsider before action. The metacognitive step allows the application of specific cognitive and affective forcing... metacognition Train for a reflective approach to problem-solving: stepping back from the immediate problem to examine and reflect on the thinking and

  7. Affective responses to dance.

    PubMed

    Christensen, Julia F; Pollick, Frank E; Lambrechts, Anna; Gomila, Antoni

    2016-07-01

    The objective of the present work was the characterization of mechanisms by which affective experiences are elicited in observers when watching dance movements. A total of 203 dance stimuli from a normed stimuli library were used in a series of independent experiments. The following measures were obtained: (i) subjective measures of 97 dance-naïve participants' affective responses (Likert scale ratings, interviews); and (ii) objective measures of the physical parameters of the stimuli (motion energy, luminance), and of the movements represented in the stimuli (roundedness, impressiveness). Results showed that (i) participants' ratings of felt and perceived affect differed, (ii) felt and perceived valence but not arousal ratings correlated with physical parameters of the stimuli (motion energy and luminance), (iii) roundedness in posture shape was related to the experience of more positive emotion than edgy shapes (1 of 3 assessed rounded shapes showed a clear effect on positiveness ratings while a second reached trend level significance), (iv) more impressive movements resulted in more positive affective responses, (v) dance triggered affective experiences through the imagery and autobiographical memories it elicited in some people, and (vi) the physical parameters of the video stimuli correlated only weakly and negatively with the aesthetics ratings of beauty, liking and interest. The novelty of the present approach was twofold; (i) the assessment of multiple affect-inducing mechanisms, and (ii) the use of one single normed stimulus set. The results from this approach lend support to both previous and present findings. Results are discussed with regards to current literature in the field of empirical aesthetics and affective neuroscience.

  8. Step by Step: Using Kodaly To Build Vocal Improvisation.

    ERIC Educational Resources Information Center

    Whitcomb, Rachel

    2003-01-01

    Describes how to teach elementary students about vocal improvisation using the Kodaly-based approach. Discusses the three steps involved in this technique: (1) develop familiar singing patterns; (2) use a question and answer format; and (3) begin improvisation. Includes examples of solfege patterns and a vocal question and answer. (CMK)

  9. A Step-by-Step Guide to Personalize Learning

    ERIC Educational Resources Information Center

    Bray, Barbara; McClaskey, Kathleen

    2013-01-01

    It is known that every learner is unique and that one-size-fits-all instruction does not work for most. How can a classroom environment be created that gives each learner voice and choice? The co-founders of Personalize Learning, LLC, offer a detailed six-step approach. This article provides the background on what is and what is not Personalized…

  10. Piezoelectric step-motion actuator

    DOEpatents

    Mentesana; Charles P.

    2006-10-10

    A step-motion actuator using piezoelectric material to launch a flight mass which, in turn, actuates a drive pawl to progressively engage and drive a toothed wheel or rod to accomplish stepped motion. Thus, the piezoelectric material converts electrical energy into kinetic energy of the mass, and the drive pawl and toothed wheel or rod convert the kinetic energy of the mass into the desired rotary or linear stepped motion. A compression frame may be secured about the piezoelectric element and adapted to pre-compress the piezoelectric material so as to reduce tensile loads thereon. A return spring may be used to return the mass to its resting position against the compression frame or piezoelectric material following launch. Alternative embodiment are possible, including an alternative first embodiment wherein two masses are launched in substantially different directions, and an alternative second embodiment wherein the mass is eliminated in favor of the piezoelectric material launching itself.

  11. Step-by-step phacoemulsification training program for ophthalmology residents

    PubMed Central

    Yulan, Wang; Yaohua, Sheng; Jinhua, Tao; Min, Wang

    2013-01-01

    Aims: The aim was to analyze the learning curve of phacoemulsification (phaco) performed by residents without experience in performing extra-capsular cataract extraction (ECCE) in a step-by-step training program (SBSTP). Materials and Methods: Consecutive surgical records of phaco performed from March 2009 to Sept 2011 by four residents without previous ECCE experience were retrospectively reviewed. The completion rate of the first 30 procedures by each resident was calculated. The main intraoperative phaco parameter records for the first 30 surgeries by each resident were compared with those for their last 30 surgeries. Intraoperative complications in the residents’ procedures were also recorded and analyzed. Results: A total of 1013 surgeries were performed by residents. The completion rate for the first 30 phaco procedures was 79.2 ± 5.8%. The main reasons for halting the procedure were as follows: Anterior capsule tear, inability to crack the nucleus, and posterior capsular rupture during phaco or cortex removal. Cumulative dissipated energy of phaco power used during the surgeries was significantly less in the last 30 cases compared with the first 30 cases (30.10 ± 17.58 vs. 55.41 ± 37.59, P = 0.021). Posterior capsular rupture rate was 2.5 ± 1.2% in total (10.8 ± 4.2% in the first 30 cases and 1.7 ± 1.9% in the last 30 cases, P = 0.008; a statistically significant difference). Conclusion: The step-by-step training program might be a necessary process for a resident to transit from dependence to a self-supported operator. It is also an essential middle step between wet lab training to performing the entire phaco procedure on the patient both effectively and safely. PMID:24178407

  12. IEA/WHO toolkit for WMSDs prevention: criteria and practical tools for a step by step approach.

    PubMed

    Occhipinti, Enrico; Colombini, Daniela

    2012-01-01

    When studying WMSDs, several determinants and their interrelationship are considered as relevant. Hence the necessity of an "holistic" approach to prevention, especially when preparing technical rules and strategic plans. There is a strong request, from OSH agencies and operators, for developing "simple" tools for risk assessment and management. In this context WHO asked IEA to develop a "Toolkit for WMSD prevention". The paper presents one of the main contribution to this WHO project, focused on selecting tools at different level for hazard identification, risk estimation and management. Proposals are based on two essential criteria: Acting on a step-by-step approach; Taking into account the presence of multiple influencing factors. The proposals consider: A Basic Step devoted to hazard identification by operative "key-enter" questions, that can be operated also by non-experts. A First Step, (quick assessment), for identifying 3 possible conditions: acceptable; high risk present; more detailed analysis (via tools presented at second step) necessary. This step can be operated by non-experts with only some specific training. A Second Step, where recognized (i.e. from international standards or guidelines) tools for risk estimation are used. This step can be operated only by persons with some specific training.

  13. Comparative study of structure and permeability of porous oxide films on aluminum obtained by single- and two-step anodization.

    PubMed

    Petukhov, Dmitrii I; Napolskii, Kirill S; Berekchiyan, Mikhail V; Lebedev, Alexander G; Eliseev, Andrey A

    2013-08-28

    A comparative study of the structure and transport properties of porous aluminum oxide films obtained by single- and two-step anodization was carried out. It is shown that the oxidation regime significantly affect the number of dead-ended channels, which results in more than twice the variation in membrane permeability. The effect is explained by multiple branching of channels on the initial stages of organization of the porous structure. Branching also occurs on later stages governing mass transport properties of porous anodic alumina films. A model describing transport properties of anodic aluminum oxide membranes based on pore branching on domain boundaries was suggested to fit experimental results of permeance of membranes obtained by both single- and two-step anodization.

  14. Steps of Reprocessing and Equipments

    PubMed Central

    Lee, Yong Kook

    2013-01-01

    With the increasing interest in endoscopy and the rising number of endoscopic examinations in hospitals, the importance of endoscopic reprocessing is also increasing. Cure facilities that are understaffed and ill-equipped are trying to cope with the problems of insufficient cleaning and high infection risks. To prevent endoscopy-associated infection, the endoscope cleaning, and disinfection guidelines prepared by the Korean Society of Gastrointestinal Endoscopy must be followed. In this review, the steps of endoscopic reprocessing and the equipments required in each step are discussed. PMID:23767039

  15. [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.

  16. Seven Steps to Successful Inclusion.

    ERIC Educational Resources Information Center

    Whitworth, Jerry

    This report highlights the experiences of the Lighthouse Project, which successfully included students with disabilities in elementary, middle, and high school general education classes in a school district in southwest Tennessee. Drawing on findings from the Lighthouse Project, the report describes the following seven steps that must be present…

  17. Ten Steps to "TQM Plus."

    ERIC Educational Resources Information Center

    Kaufman, Roger; Hirumi, Atsusi

    1992-01-01

    Total Quality Management Plus (TQM) goes beyond customer satisfaction to consider quality of life, environmental conditions, crime rates, and health and well-being. Steps to integrate such concerns into the TQM process include being ready for challenges, creating a quality system to collect performance data, defining the ideal school and world…

  18. Design of converging stepped spillways

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Roller compacted concrete (RCC) stepped spillways are growing in popularity for providing overtopping protection for aging watershed dams with inadequate auxiliary spillway capacity and for the construction of new dams. Unobtainable land rights, topographic features, and land use changes caused by ...

  19. Evaluation of Florida's STEP Program.

    ERIC Educational Resources Information Center

    Florida State Dept. of Health and Rehabilitative Services, Tallahassee.

    Project STEP (Short Term Elective Program) is an outdoor-educational program that, through teaching wilderness survival skills and affording a necessity for their use, provides juvenile delinquents with a feeling of self-reliance and self-worth. The program is designed for committed youths, primarily males, at least 13 to 14 years of age, but…

  20. Ten Steps for Peace Education

    ERIC Educational Resources Information Center

    n/a

    2005-01-01

    This brief guide is for parents and teachers who seek to nurture the values of compassion and good will in their children?s lives. It describes ten steps or actions to promote peace and goodwill in the home, in family activities, and in school.

  1. One-Step Coal Liquefaction

    NASA Technical Reports Server (NTRS)

    Qader, S. A.

    1984-01-01

    Steam injection improves yield and quality of product. Single step process for liquefying coal increases liquid yield and reduces hydrogen consumption. Principal difference between this and earlier processes includes injection of steam into reactor. Steam lowers viscosity of liquid product, so further upgrading unnecessary.

  2. Muscle synergies involved in shifting the center of pressure while making a first step.

    PubMed

    Wang, Yun; Zatsiorsky, Vladimir M; Latash, Mark L

    2005-11-01

    We used the framework of the uncontrolled manifold (UCM) hypothesis to analyze multi-muscle synergies involved in making a step by a standing person. We hypothesized that leg and trunk muscles are organized into stable groups (muscle modes, M-modes) related to shifts of the center of pressure (COP) in the anterior-posterior and medio-lateral directions. Another hypothesis was that the magnitudes of the modes co-vary across repetitive trials to stabilize a certain magnitude of the COP shift in both directions. M-modes were defined using principal component analysis applied to indices of changes in the electromyographic (EMG) activity prior to releasing variable loads that were held by the subject using a pulley system. For the task of releasing the load behind the body three M-modes associated with a backward COP shift were defined. Four M-modes were defined for the task of releasing the load at the body side associated with a lateral COP shift. Multiple regression analysis was used to relate changes in the M-mode magnitudes to COP shifts. EMG changes prior to making a step were quantified over five 100 ms time windows before the lift-off of the stepping leg. Two components of the variance in the M-mode space computed across repetitions of a stepping task were quantified-a component that did not affect the average COP shift in a particular direction (variance within the UCM, V (UCM)), and a component that affected the COP shift (variance orthogonal to the UCM, V (ORT)). V (UCM) was significantly higher than V (ORT) for both directions of the COP shifts. This relation was observed for the M-modes in the stepping leg as well as in the support leg. The stepping leg showed a different time evolution of the ratio V (UCM)/V (ORT) such that the difference between the two variance components disappeared closer to the time of the lift-off. The findings corroborate both main hypotheses. The study supports a view that control of whole-body actions involves grouping the muscles

  3. Experimental study on cyclic steps formed by surge-type turbidity currents

    NASA Astrophysics Data System (ADS)

    Yokokawa, M.; Shozakai, D.; Higuchi, H.; Hughes Clarke, J. E.; Izumi, N.

    2015-12-01

    Field observations of turbidity currents and seabed topography on the Squamish delta in Howe Sound, British Columbia, Canada have been undertaken which found bedwaves actively migrating in the upstream direction in channels formed on the prodelta slope (Hughes Clarke et al., 2012a; 2012b; 2014; Figure 1). Their topography and behaviour suggest that they are cyclic steps formed by the surge-type turbidity currents. There has been no experimental study to investigate the formative conditions of cyclic steps by the surge-type turbidity currents. We did preliminary experiments on the formation of cyclic steps due to the multiple surge-type density currents, and compare the morphology of the steps with those of Squamish delta. The experiments had been performed at Osaka Institute of Technology. A flume, which is 3.6 m long, 0.3 m deep and 2 cm wide, was submerged into a larger flume, which is 4 m long, 0.4 m deep and 8 cm wide, filled with water. Mixture of salt water (1.18 g/cm3) and plastic particles (1.5 g/cm3, 0.1-0.18 mm in diameter) poured into the upstream end of the inner flume by hand using a funnel. For the example introduced here, the slope of the outer flume was 1.5 degrees, and the mixtures' whole weight and volumetric concentration ranged from 310 g (3.23 vol.%) to 510 g (8.16 vol.%). These mixtures were poured 105 times, and the thickness of the deposits was measured every 50 cm by photographs. As a result, two mounds (steps) were formed ultimately, which are moving toward upstream direction. Wavelengths are 80 cm and 120 cm respectively. The two kinds of flow depth were measured from photograph, such as the whole thickness of the flow, and the thickness of the lower high-density layer. Calculating the wave steepness and non-dimensional wave number, it turns out that those values using the thickness of the lower high-density layer fall into the region very close to the Squamish data that assuming the flow depth as 0.5 m. This could lead the following

  4. Dissecting a complex neurosurgical illustration: step-by-step development.

    PubMed

    Suk, Ian

    2011-12-01

    Modern computer graphics software has enabled the medical illustrator to render very complex anatomy by composing many different layers of drawings simultaneously. This and the author's capacity to take an "editorial" approach to compress several chronological events into a single, comprehensive two-dimensional illustration are analyzed in a step-by-step process. Through a series of images, the article provides a visual synopsis of the development of an illustration for an extensive clinical case: total sacrectomy performed through an all-posterior approach. Originally given as a slide presentation at the American Association of Neurological Surgeons Theodore Kurze Lecture in April 2011, the article provides some detailed notes on the techniques the author used to develop a comprehensive neurosurgical illustration.

  5. 2-Step IMAT and 2-Step IMRT in three dimensions

    SciTech Connect

    Bratengeier, Klaus

    2005-12-15

    In two dimensions, 2-Step Intensity Modulated Arc Therapy (2-Step IMAT) and 2-Step Intensity Modulated Radiation Therapy (IMRT) were shown to be powerful methods for the optimization of plans with organs at risk (OAR) (partially) surrounded by a target volume (PTV). In three dimensions, some additional boundary conditions have to be considered to establish 2-Step IMAT as an optimization method. A further aim was to create rules for ad hoc adaptations of an IMRT plan to a daily changing PTV-OAR constellation. As a test model, a cylindrically symmetric PTV-OAR combination was used. The centrally placed OAR can adapt arbitrary diameters with different gap widths toward the PTV. Along the rotation axis the OAR diameter can vary, the OAR can even vanish at some axis positions, leaving a circular PTV. The width and weight of the second segment were the free parameters to optimize. The objective function f to minimize was the root of the integral of the squared difference of the dose in the target volume and a reference dose. For the problem, two local minima exist. Therefore, as a secondary criteria, the magnitude of hot and cold spots were taken into account. As a result, the solution with a larger segment width was recommended. From plane to plane for varying radii of PTV and OAR and for different gaps between them, different sets of weights and widths were optimal. Because only one weight for one segment shall be used for all planes (respectively leaf pairs), a strategy for complex three-dimensional (3-D) cases was established to choose a global weight. In a second step, a suitable segment width was chosen, minimizing f for this global weight. The concept was demonstrated in a planning study for a cylindrically symmetric example with a large range of different radii of an OAR along the patient axis. The method is discussed for some classes of tumor/organ at risk combinations. Noncylindrically symmetric cases were treated exemplarily. The product of width and weight of

  6. Multiple Sclerosis

    MedlinePlus

    ... eyes, causing blurred or double vision, or red-green color distortion. However, symptoms can also affect different ... The tests will look for changes in eye movements, muscle coordination, weakness, balance, sensation, speech, and reflexes. ...

  7. [The central vein catheterization. 2. Procedure, step by step].

    PubMed

    Schmalz-Ott, Stéphane; Monti, Matteo; Vollenweider, Peter

    2008-10-29

    Several approaches exist for central vein catheterization. Mastery of the various steps of this procedure and understanding of the basics of asepsis are critical to prevent any complication. They also built the basis for an exhaustive communication with the patient, to obtain an informed consent. This article can in addition be used to develop a checklist in order to (self-)assess competence in procedural skills.

  8. Undertaking a literature review: a step-by-step approach.

    PubMed

    Cronin, Patricia; Ryan, Frances; Coughlan, Michael

    Nowadays, most nurses, pre- and post-qualification, will be required to undertake a literature review at some point, either as part of a course of study, as a key step in the research process, or as part of clinical practice development or policy. For student nurses and novice researchers it is often seen as a difficult undertaking. It demands a complex range of skills, such as learning how to define topics for exploration, acquiring skills of literature searching and retrieval, developing the ability to analyse and synthesize data as well as becoming adept at writing and reporting, often within a limited time scale. The purpose of this article is to present a step-by-step guide to facilitate understanding by presenting the critical elements of the literature review process. While reference is made to different types of literature reviews, the focus is on the traditional or narrative review that is undertaken, usually either as an academic assignment or part of the research process.

  9. Finger Multiplication

    ERIC Educational Resources Information Center

    Holmes, Bill

    2010-01-01

    The author has been prompted to write this article about finger multiplication for a number of reasons. Firstly there are a number of related articles in past issues of "Mathematics Teaching" ("MT") which have connections to this algorithm. Secondly, very few of his primary teaching students and professional colleagues appear to be aware of the…

  10. Multiple Sclerosis.

    ERIC Educational Resources Information Center

    Plummer, Nancy; Michael, Nancy, Ed.

    This module on multiple sclerosis is intended for use in inservice or continuing education programs for persons who administer medications in long-term care facilities. Instructor information, including teaching suggestions, and a listing of recommended audiovisual materials and their sources appear first. The module goal and objectives are then…

  11. Multiple Intelligences.

    ERIC Educational Resources Information Center

    Laughlin, Janet

    1999-01-01

    Details the characteristics of Howard Gardner's seven multiple intelligences (MI): linguistic, logical-mathematical, bodily-kinesthetic, spatial, musical, interpersonal, and intrapersonal. Discusses the implications of MI for instruction. Explores how students can study using their preferred learning style - visual, auditory, and physical study…

  12. Longitudinal Changes in Self-Reported Walking Ability in Multiple Sclerosis

    PubMed Central

    Motl, Robert W.; Putzki, Norman; Pilutti, Lara A.; Cadavid, Diego

    2015-01-01

    Background Patient-reported outcomes are increasingly used to understand the clinical meaningfulness of multiple sclerosis disability and its treatments. For example, the 12-item Multiple Sclerosis Walking Scale (MSWS-12) measures the patient-reported impact of the disease on walking ability. Objective We studied longitudinal changes in walking ability using the MSWS-12 in a cohort of 108 patients with relapsing-remitting multiple sclerosis and moderate-to-severe disability from a single US center cohort study investigating multiple sclerosis symptoms and physical activity. Methods The MSWS-12 was completed every 6 months over 2 years together with self-reported measures of disease impact on daily life (Multiple Sclerosis Impact Scale) and walking disability (Patient Determined Disease Steps scale). Results The results revealed a high frequency of self-reported changes in walking ability at the individual level, affecting approximately 80% of patients for all four time periods. MSWS-12 scores remained stable at the group level for all four time periods. The magnitude of observed changes at the individual level was higher than the proposed minimal clinically important differences of 4 or 6 points and correlated better with Multiple Sclerosis Impact Scale physical scores than psychological scores, but little with self-reported Patient Determined Disease Steps Scale scores. Conclusions This novel finding of frequent fluctuations in self-reported walking ability is new and requires further investigation. PMID:25932911

  13. Segmented Coil Fails In Steps

    NASA Technical Reports Server (NTRS)

    Stedman, Ronald S.

    1990-01-01

    Electromagnetic coil degrades in steps when faults occur, continues to operate at reduced level instead of failing catastrophically. Made in segments connected in series and separated by electrically insulating barriers. Fault does not damage adjacent components or create hazard. Used to control valves in such critical applications as cooling systems of power generators and chemical process equipment, where flammable liquids or gases handled. Also adapts to electrical control of motors.

  14. Meissner-Effect Stepping Motor

    NASA Technical Reports Server (NTRS)

    Robertson, Glen A.

    1991-01-01

    Proposed stepping motor derives torque from diamagnetic repulsion produced by Meissner effect - exclusion of magnetic field from interior of superconductor. Design of motor takes advantage of silver-doped YB2Cu3O and other compounds superconductive at temperatures as high as that of liquid nitrogen. Skin of rotor cooled below its superconducting-transition temperature by liquid nitrogen. O-rings prevent leaks of liquid nitrogen from rotor. Weight, cost, and maintenance reduced.

  15. Stepped frequency ground penetrating radar

    DOEpatents

    Vadnais, Kenneth G.; Bashforth, Michael B.; Lewallen, Tricia S.; Nammath, Sharyn R.

    1994-01-01

    A stepped frequency ground penetrating radar system is described comprising an RF signal generating section capable of producing stepped frequency signals in spaced and equal increments of time and frequency over a preselected bandwidth which serves as a common RF signal source for both a transmit portion and a receive portion of the system. In the transmit portion of the system the signal is processed into in-phase and quadrature signals which are then amplified and then transmitted toward a target. The reflected signals from the target are then received by a receive antenna and mixed with a reference signal from the common RF signal source in a mixer whose output is then fed through a low pass filter. The DC output, after amplification and demodulation, is digitized and converted into a frequency domain signal by a Fast Fourier Transform. A plot of the frequency domain signals from all of the stepped frequencies broadcast toward and received from the target yields information concerning the range (distance) and cross section (size) of the target.

  16. A double blind, placebo-controlled, phase II, add-on study of cyclophosphamide (CTX) for 24 months in patients affected by multiple sclerosis on a background therapy with interferon-beta study denomination: CYCLIN.

    PubMed

    Patti, F; Amato, M P; Filippi, M; Gallo, P; Trojano, M; Comi, G C

    2004-08-15

    The authors present and discuss a new protocol for active multiple sclerosis (MS) patients. A double blind randomized controlled multicenter study was planned to study the effects of a combination regimen therapy: cyclophosphamide plus beta interferon versus beta interferon alone on both relapsing-remitting and secondary MS patients with active disease. The primary endpoint of this study is the number of new gadolinium enhancing lesions at MRI evaluation. Secondary endpoints are new T2 lesions, new T1 lesions, T2 lesion load, T1 lesion load, cerebral atrophy, number of patients who were relapse-free, number of patients who improved, yearly relapses, quality of life, disability and cognitive impairment, frequency of neutralizing antibodies, safety of the combination therapy (cyclophosphamide + beta interferon). The study will enroll 225 patients in 25 Italian MS centers. Eligible for the study are patients with either relapsing-remitting or secondary MS according McDonald criteria on 6-24 months beta interferon treatment with active disease (new gadolinium enhancing lesion or who experienced a new relapse on beta interferon treatment). Clinical evaluation will be performed every 4 months, MRI yearly. Vital signs and eventual adverse events will be collected monthly. The study will last 36 months, 12 for the enrollment phase and 24 for the treatment phase. The study will start on April 2004.

  17. Acta Clinica Croatica: progress of a journal step by step.

    PubMed

    Ramljak, Gordana

    2014-03-01

    The journal Acta Clinica Croatica (ACC) was founded in 1962 under the title Anali Bolnice Dr. M. Stojanović. In 1995, the title of the journal was changed into its present form and ever since all papers have been published in English. In 2000, the electronic (online) edition of the ACC was released in addition to the print version. The paper presents development of the journal from 1962 to 2012 based on the analysis of the following SCOPUS citation index parameters: type and number of documents published in the journal; number of citations; and number of domestic and foreign authors. The studied period was analyzed in three time segments: the period from 1995 to 1999, the period from 2000 to 2006 and the period from 2007 to 2012. The same parameters were analyzed in the Web of Science/SCI-Expanded bibliographic and citation index for the 2007-2012 period. The increasing number of documents, authors (both domestic and foreign) and citations demonstrates gradual rise in the quality, visibility and impact of the journal. The fifty years of experience show that a goal, at first very distant and almost unachievable, may be reached by progressing step by step.

  18. Exergaming in Older Adults: Movement Characteristics While Playing Stepping Games

    PubMed Central

    Skjæret-Maroni, Nina; Vonstad, Elise K.; Ihlen, Espen A. F.; Tan, Xiang-Chun; Helbostad, Jorunn L.; Vereijken, Beatrix

    2016-01-01

    Despite frequent use of exergames in intervention studies to improve physical function in older adults, we lack knowledge about the movements performed during exergaming. This causes difficulties for interpreting results of intervention studies and drawing conclusions about the efficacy of exergames to exercise specific functions important for the elderly population. The aim of the current study was to investigate whether game and game level affect older adults’ stepping and upper body movements while playing stepping exergames. A 3D-motion capture experiment was performed with 20 elderly (12 women and 8 men; age range 65–90 years), playing two exergames, The Mole from SilverFit and LightRace in YourShape: Fitness Evolved, on two difficulty levels, with five 1-min trials for each game and level. Reflective markers were placed on bases of first toe, heels, and lower back. Movement characteristics were analyzed with a linear mixed model. Results indicated that both game and game level affected movement characteristics. Participants took shorter steps and had lower step velocity when playing The Mole compared to LightRace, while The Mole prompted more variation in step length and step velocity. Compared to LightRace, The Mole elicited larger upper body movements in both ML- and AP-directions and participants’ feet and upper body covered a larger area. Increasing difficulty level from Easy to Medium resulted in overall decrease of movement, except for number of steps and step speed when playing LightRace. Even with only two games, two levels, and five trials at each, this study indicates that the choice of exergame is not indifferent when aiming to exercise specific functions in older adults and that exergames need to be chosen and designed carefully based on the goals of the intervention. PMID:27445926

  19. Quality science for all: A qualitative study of professional development and assessment implementation in STEP-uP

    NASA Astrophysics Data System (ADS)

    Funk, Christine M.

    One of the most important factors in achieving scientific literacy is for science teachers at the local level to develop a greater understanding of science education, including science content, pedagogy, and assessment. This study was designed to examine the connection between teacher learning and practice by studying the relationship between professional development and assessment implementation in the elementary science classroom. The goal was to develop a deeper understanding of the components of the STEP-uP model that served as a catalyst for change and to provide insight into how to best work with teachers in order to develop a more scientifically literate population. Four essential questions guided this research. What kinds of opportunities does STEP-uP provide for elementary school teachers to improve their assessment practices in science? In what ways did STEP-uP training affect assessment practices by teachers? How, if at all, are the assessment practices modified by teachers? What are the most salient features of the STEP-uP professional development model that allow for change and growth in assessment practices in elementary science classrooms and for education at large? The research method for this study was educational connoisseurship and criticism. I developed rich descriptions and interpretations based on observations, interviews, and artifacts from six classroom teachers which were then compared and contrasted to the goals of STEP-uP described in their literature, by the assessment coordinator, and an observation of a STEP-uP training. Key findings include: (1) collaboration and collegial support must be integral to sustain change; (2) clearly articulated goals form one, cohesive vision for professional development that must be integral to all components of the program; (3) multiple entry points help encourage participation and honor differences between teachers' personal and professional needs; and, (4) classroom structures such as time, classroom

  20. Multiple myeloma

    PubMed Central

    Rajkumar, S. Vincent

    2008-01-01

    Multiple myeloma is a clonal plasma cell malignancy that accounts for slightly more than 10% of all hematologic cancers. In this paper, we present a historically focused review of the disease, from the description of the first case in 1844 to the present. The evolution of drug therapy and stem-cell transplantation for the treatment of myeloma, as well as the development of new agents, is discussed. We also provide an update on current concepts of diagnosis and therapy, with an emphasis on how treatments have emerged from a historical perspective after certain important discoveries and the results of experimental studies. PMID:18332230

  1. Lessons learned in stepped chute research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Early research on stepped chutes focused on steep gravity style stepped chutes. Today, the research trend has shifted to stepped chutes applied to more moderate slopes like those for aging embankment dams. Research contributions have been made on hydraulic properties of stepped chutes including ai...

  2. Hydraulic Design of Stepped Spillways Workshop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stepped chutes and spillways are commonly used for routing discharges during flood events. In addition, stepped chutes are used for overtopping protection of earthen embankments. Stepped spillways provide significant energy dissipation due to its stepped feature; as a result, the stilling basin as...

  3. Single-step assembly of complex 3-D microstructures

    SciTech Connect

    Hui, E.E.; Howe, R.T.; Rodgers, M.S.

    2000-01-04

    This paper describes three-dimensional microstructures fabricated in a planar process and assembled in a single step. Multiple plates are constrained by hinges in such a way as to reduce the assembly process to a single degree-of-freedom of motion. Serial microassembly of these structures is simpler; moreover, self-assembly using hydrodynamic forces during release is much more feasible than with earlier, multiple degree-of-freedom hinged structures. A 250-{micro}m corner cube reflector, a 6-sided closed box, and a 3-D model of the Berkeley Campanile clock tower have been demonstrated in the 4-level polysilicon SUMMiT MEMS foundry.

  4. What Promotes Wisdom in 12-Step Recovery?

    PubMed

    DiGangi, Julia A; Majer, John M; Mendoza, Leslie; Droege, Jocelyn R; Jason, Leonard A; Contreras, Richard

    2014-01-01

    Research investigations on twelve-step groups such as Alcoholics Anonymous (AA) and Narcotics Anonymous (NA) have addressed a number of resources associated with 12-step recovery. However, little is known about the role of wisdom, and whether aspects of 12-step participation might increase this resource among 12-step members. An exploratory analysis revealed that participants who reported having a "spiritual awakening" and considered themselves "members" of 12-step groups reported significantly higher levels of wisdom. Twelve-step meeting attendance was not significantly related to wisdom scores. Findings suggest certain aspects of 12-step involvement are associated with wisdom and may play a role in substance abuse recovery.

  5. Step-induced magnetic anisotropy in Co/stepped Cu(001) as a function of step density and Cu step decoration

    SciTech Connect

    Kawakami, R.K.; Bowen, M.O.; Choi, H.J.; Escorcia-Aparicio, E.J.; Qiu, Z.Q.

    1999-04-01

    The step-induced in-plane uniaxial magnetic anisotropy of fcc Co/stepped Cu(001) was investigated using a curved substrate to provide a continuous range of vicinal angles from 0{degree} to 6{degree}. The anisotropy strength was found to depend linearly on the step density, indicating that the biaxial strain does not make a significant contribution to the step-induced anisotropy. Using a side growth geometry to decorate the Co step edges with Cu adsorbates, we observed that the step-induced anisotropy strength approaches zero at roughly 0.7 atomic rows of Cu, independent of step density. {copyright} {ital 1999 American Institute of Physics.}

  6. Immersed Boundary Fractional Step Method

    NASA Astrophysics Data System (ADS)

    Taira, Kunihiko

    2005-11-01

    We present a new formulation of the immersed boundary method for incompressible flow over moving rigid bodies. Like many existing techniques we introduce a set of interpolation points on the surface at which the no-slip boundary condition is satisfied by including a (regularized) force in the momentum equations. By introducing interpolation and regularization operators and grouping pressure and force unknowns together, the discretized Navier-Stokes equations with the immersed boundary method can be formulated with an identical structure to the traditional fractional step method, but with a modified Poisson equation whose unknowns are both the pressure and the boundary force. The method highlights the analogous roles of pressure and boundary forcing as Lagrange multipliers in order to satisfy the divergence free and no-slip constraints, respectively. The overall method is found to be a simple addition to an existing fractional step code and the extended Poisson equation is solved efficiently with the conjugate gradient method. We demonstrate convergence and present results for two-dimensional flows with a variety of moving rigid bodies.

  7. Multiple Inflation

    NASA Astrophysics Data System (ADS)

    Murphy, Philip Joseph

    1987-09-01

    The Theory of Inflation, namely, that at some point the entropy content of the universe was greatly increased, has much promise. It may solve the puzzles of homogeneity and the creation of structure. However, no particle physics model has yet been found that can successfully drive inflation. The difficulty in satisfying the constraint that the isotropy of the microwave background places on the effective potential of prospective models is immense. In this work we have codified the requirements of such models in a most general form. We have carefully calculated the amounts of inflation the various problems of the Standard Model need for their solution. We have derived a completely model independent upper bound on the inflationary Hubble parameter. We have developed a general notation with which to probe the possibilities of Multiple Inflation. We have shown that only in very unlikely circumstances will any evidence of an earlier inflation, survive the de Sitter period of its successor. In particular, it is demonstrated that it is most unlikely that two bouts of inflation will yield high amplitudes of density perturbations on small scales and low amplitudes on large. We conclude that, while multiple inflation will be of great theoretical interest, it is unlikely to have any observational impact.

  8. One School...One Step.

    ERIC Educational Resources Information Center

    Westberry, Lee

    Overcoming parents' negative stereotypes of career and technical education (CTE) is the goal of the Business and Education Symposium (BES) at Stratford High School, Goose Creek, South Carolina. The BES program has these four main goals: (1) educate parents about the changing demands of the workforce, so as to affect student course selection; (2)…

  9. Unitary step of gliding machinery in Mycoplasma mobile

    PubMed Central

    Kinosita, Yoshiaki; Nakane, Daisuke; Sugawa, Mitsuhiro; Masaike, Tomoko; Mizutani, Kana; Miyata, Makoto; Nishizaka, Takayuki

    2014-01-01

    Among the bacteria that glide on substrate surfaces, Mycoplasma mobile is one of the fastest, exhibiting smooth movement with a speed of 2.0–4.5 μm⋅s−1 with a cycle of attachment to and detachment from sialylated oligosaccharides. To study the gliding mechanism at the molecular level, we applied an assay with a fluorescently labeled and membrane-permeabilized ghost model, and investigated the motility by high precision colocalization microscopy. Under conditions designed to reduce the number of motor interactions on a randomly oriented substrate, ghosts took unitary 70-nm steps in the direction of gliding. Although it remains possible that the stepping behavior is produced by multiple interactions, our data suggest that these steps are produced by a unitary gliding machine that need not move between sites arranged on a cytoskeletal lattice. PMID:24912194

  10. Unitary step of gliding machinery in Mycoplasma mobile.

    PubMed

    Kinosita, Yoshiaki; Nakane, Daisuke; Sugawa, Mitsuhiro; Masaike, Tomoko; Mizutani, Kana; Miyata, Makoto; Nishizaka, Takayuki

    2014-06-10

    Among the bacteria that glide on substrate surfaces, Mycoplasma mobile is one of the fastest, exhibiting smooth movement with a speed of 2.0-4.5 μm⋅s(-1) with a cycle of attachment to and detachment from sialylated oligosaccharides. To study the gliding mechanism at the molecular level, we applied an assay with a fluorescently labeled and membrane-permeabilized ghost model, and investigated the motility by high precision colocalization microscopy. Under conditions designed to reduce the number of motor interactions on a randomly oriented substrate, ghosts took unitary 70-nm steps in the direction of gliding. Although it remains possible that the stepping behavior is produced by multiple interactions, our data suggest that these steps are produced by a unitary gliding machine that need not move between sites arranged on a cytoskeletal lattice.

  11. Single-step quantitative susceptibility mapping with variational penalties.

    PubMed

    Chatnuntawech, Itthi; McDaniel, Patrick; Cauley, Stephen F; Gagoski, Borjan A; Langkammer, Christian; Martin, Adrian; Grant, P Ellen; Wald, Lawrence L; Setsompop, Kawin; Adalsteinsson, Elfar; Bilgic, Berkin

    2017-04-01

    Quantitative susceptibility mapping (QSM) estimates the underlying tissue magnetic susceptibility from the gradient echo (GRE) phase signal through background phase removal and dipole inversion steps. Each of these steps typically requires the solution of an ill-posed inverse problem and thus necessitates additional regularization. Recently developed single-step QSM algorithms directly relate the unprocessed GRE phase to the unknown susceptibility distribution, thereby requiring the solution of a single inverse problem. In this work, we show that such a holistic approach provides susceptibility estimation with artifact mitigation and develop efficient algorithms that involve simple analytical solutions for all of the optimization steps. Our methods employ total variation (TV) and total generalized variation (TGV) to jointly perform the background removal and dipole inversion in a single step. Using multiple spherical mean value (SMV) kernels of varying radii permits high-fidelity background removal whilst retaining the phase information in the cortex. Using numerical simulations, we demonstrate that the proposed single-step methods reduce the reconstruction error by up to 66% relative to the multi-step methods that involve SMV background filtering with the same number of SMV kernels, followed by TV- or TGV-regularized dipole inversion. In vivo single-step experiments demonstrate a dramatic reduction in dipole streaking artifacts and improved homogeneity of image contrast. These acquisitions employ the rapid three-dimensional echo planar imaging (3D EPI) and Wave-CAIPI (controlled aliasing in parallel imaging) trajectories for signal-to-noise ratio-efficient whole-brain imaging. Herein, we also demonstrate the multi-echo capability of the Wave-CAIPI sequence for the first time, and introduce an automated, phase-sensitive coil sensitivity estimation scheme based on a 4-s calibration acquisition. Copyright © 2016 John Wiley & Sons, Ltd.

  12. [Multiple apheresis].

    PubMed

    Coffe, C

    2007-05-01

    Multiple apheresis makes it possible to obtain at least two labile blood components from a single donor using a cell separator. It can be either multicomponent apheresis leading to the preparation of at least two different blood component types or red blood cell apheresis providing two identical red blood cell concentrates. These techniques available in addition to whole blood donation, are modifying collection strategies in many Etablissements Français du Sang and will contribute to improve stock logistics in the future. In areas with insufficient stock, these procedures will help achieve blood component self-sufficiency. The author first describes the principle underlying different--current or future--techniques as well as their advantages and drawbacks. He finally addresses the potential impact of these processes on the evolution of blood collection and the advantages to be gained.

  13. Moral transhumanism: the next step.

    PubMed

    Tennison, Michael N

    2012-08-01

    Although transhumanism offers hope for the transcendence of human biological limitations, it generates many intrinsic and consequential ethical concerns. The latter include issues such as the exacerbation of social inequalities and the exponentially increasing technological capacity to cause harm. To mitigate these risks, many thinkers have initiated investigations into the possibility of moral enhancement that could limit the power disparities facilitated by biotechnological enhancement. The arguments often focus on whether moral enhancement is morally permissible, or even obligatory, and remain largely in the realm of the hypothetical. This paper proposes that psilocybin may represent a viable, practical option for moral enhancement and that its further research in the context of moral psychology could comprise the next step in the development of moral transhumanism.

  14. Neutron multiplicity analysis tool

    SciTech Connect

    Stewart, Scott L

    2010-01-01

    I describe the capabilities of the EXCOM (EXcel based COincidence and Multiplicity) calculation tool which is used to analyze experimental data or simulated neutron multiplicity data. The input to the program is the count-rate data (including the multiplicity distribution) for a measurement, the isotopic composition of the sample and relevant dates. The program carries out deadtime correction and background subtraction and then performs a number of analyses. These are: passive calibration curve, known alpha and multiplicity analysis. The latter is done with both the point model and with the weighted point model. In the current application EXCOM carries out the rapid analysis of Monte Carlo calculated quantities and allows the user to determine the magnitude of sample perturbations that lead to systematic errors. Neutron multiplicity counting is an assay method used in the analysis of plutonium for safeguards applications. It is widely used in nuclear material accountancy by international (IAEA) and national inspectors. The method uses the measurement of the correlations in a pulse train to extract information on the spontaneous fission rate in the presence of neutrons from ({alpha},n) reactions and induced fission. The measurement is relatively simple to perform and gives results very quickly ({le} 1 hour). By contrast, destructive analysis techniques are extremely costly and time consuming (several days). By improving the achievable accuracy of neutron multiplicity counting, a nondestructive analysis technique, it could be possible to reduce the use of destructive analysis measurements required in safeguards applications. The accuracy of a neutron multiplicity measurement can be affected by a number of variables such as density, isotopic composition, chemical composition and moisture in the material. In order to determine the magnitude of these effects on the measured plutonium mass a calculational tool, EXCOM, has been produced using VBA within Excel. This

  15. Topographic ERP analyses: a step-by-step tutorial review.

    PubMed

    Murray, Micah M; Brunet, Denis; Michel, Christoph M

    2008-06-01

    In this tutorial review, we detail both the rationale for as well as the implementation of a set of analyses of surface-recorded event-related potentials (ERPs) that uses the reference-free spatial (i.e. topographic) information available from high-density electrode montages to render statistical information concerning modulations in response strength, latency, and topography both between and within experimental conditions. In these and other ways these topographic analysis methods allow the experimenter to glean additional information and neurophysiologic interpretability beyond what is available from canonical waveform analyses. In this tutorial we present the example of somatosensory evoked potentials (SEPs) in response to stimulation of each hand to illustrate these points. For each step of these analyses, we provide the reader with both a conceptual and mathematical description of how the analysis is carried out, what it yields, and how to interpret its statistical outcome. We show that these topographic analysis methods are intuitive and easy-to-use approaches that can remove much of the guesswork often confronting ERP researchers and also assist in identifying the information contained within high-density ERP datasets.

  16. A Step by Step Protocol for Subretinal Surgery in Rabbits

    PubMed Central

    Al-Nawaiseh, Sami; Thieltges, Fabian; Liu, Zengping; Strack, Claudine; Brinken, Ralf; Braun, Norbert; Wolschendorf, Marc; Maminishkis, Arvydas; Eter, Nicole; Stanzel, Boris V.

    2016-01-01

    Age related macular degeneration (AMD), retinitis pigmentosa, and other RPE related diseases are the most common causes for irreversible loss of vision in adults in industrially developed countries. RPE transplantation appears to be a promising therapy, as it may replace dysfunctional RPE, restore its function, and thereby vision. Here we describe a method for transplanting a cultured RPE monolayer on a scaffold into the subretinal space (SRS) of rabbits. After vitrectomy xenotransplants were delivered into the SRS using a custom made shooter consisting of a 20-gauge metallic nozzle with a polytetrafluoroethylene (PTFE) coated plunger. The current technique evolved in over 150 rabbit surgeries over 6 years. Post-operative follow-up can be obtained using non-invasive and repetitive in vivo imaging such as spectral domain optical coherence tomography (SD-OCT) followed by perfusion-fixed histology. The method has well-defined steps for easy learning and high success rate. Rabbits are considered a large eye animal model useful in preclinical studies for clinical translation. In this context rabbits are a cost-efficient and perhaps convenient alternative to other large eye animal models. PMID:27684952

  17. A Step by Step Protocol for Subretinal Surgery in Rabbits.

    PubMed

    Al-Nawaiseh, Sami; Thieltges, Fabian; Liu, Zengping; Strack, Claudine; Brinken, Ralf; Braun, Norbert; Wolschendorf, Marc; Maminishkis, Arvydas; Eter, Nicole; Stanzel, Boris V

    2016-09-13

    Age related macular degeneration (AMD), retinitis pigmentosa, and other RPE related diseases are the most common causes for irreversible loss of vision in adults in industrially developed countries. RPE transplantation appears to be a promising therapy, as it may replace dysfunctional RPE, restore its function, and thereby vision. Here we describe a method for transplanting a cultured RPE monolayer on a scaffold into the subretinal space (SRS) of rabbits. After vitrectomy xenotransplants were delivered into the SRS using a custom made shooter consisting of a 20-gauge metallic nozzle with a polytetrafluoroethylene (PTFE) coated plunger. The current technique evolved in over 150 rabbit surgeries over 6 years. Post-operative follow-up can be obtained using non-invasive and repetitive in vivo imaging such as spectral domain optical coherence tomography (SD-OCT) followed by perfusion-fixed histology. The method has well-defined steps for easy learning and high success rate. Rabbits are considered a large eye animal model useful in preclinical studies for clinical translation. In this context rabbits are a cost-efficient and perhaps convenient alternative to other large eye animal models.

  18. Keeping Track Every Step of the Way

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Knowledge Sharing Systems, Inc., a producer of intellectual assets management software systems for the federal government, universities, non-profit laboratories, and private companies, constructed and presently manages the NASA Technology Tracking System, also known as TechTracS. Under contract to Langley Research Center, TechTracS identifies and captures all NASA technologies, manages the patent prosecution process, and then tracks their progress en route to commercialization. The system supports all steps involved in various technology transfer activities, and is considered the premier intellectual asset management system used in the federal government today. NASA TechTracS consists of multiple relational databases and web servers, located at each of the 10 field centers, as well as NASA Headquarters. The system is capable of supporting the following functions: planning commercial technologies; commercialization activities; reporting new technologies and inventions; and processing and tracking intellectual property rights, licensing, partnerships, awards, and success stories. NASA TechTracS is critical to the Agency's ongoing mission to commercialize its revolutionary technologies in a variety of sectors within private industry, both aerospace and non- aerospace.

  19. Neuregulin: First Steps Towards a Structure

    NASA Technical Reports Server (NTRS)

    Ferree, D. S.; Malone, C. C.; Karr, L. J.

    2003-01-01

    Neuregulins are growth factor domain proteins with diverse bioactivities, such as cell proliferation, receptor binding, and differentiation. Neureguh- 1 binds to two members of the ErbB class I tyrosine kinase receptors, ErbB3 and ErbB4. A number of human cancers overexpress the ErbB receptors, and neuregulin can modulate the growth of certain cancer types. Neuregulin-1 has been shown to promote the migration of invasive gliomas of the central nervous system. Neuregulin has also been implicated in schizophrenia, multiple sclerosis and abortive cardiac abnormalities. The full function of neuregulin-1 is not known. In this study we are inserting a cDNA clone obtained from American Type Culture Collection into E.coli expression vectors to express neuregulin- 1 protein. Metal chelate affinity chromatography is used for recombinant protein purification. Crystallization screening will proceed for X-ray diffraction studies following expression, optimization, and protein purification. In spite of medical and scholarly interest in the neuregulins, there are currently no high-resolution structures available for these proteins. Here we present the first steps toward attaining a high-resolution structure of neuregulin- 1, which will help enable us to better understand its function

  20. A Novel Multi-carrier Radar for High-speed Wide-bandwidth Stepped-Frequency GPR

    NASA Astrophysics Data System (ADS)

    Kyoo Kim, Dong; Choi, Young Woo; Kang, Do Wook

    2015-04-01

    the paved road. To make it fast, the frequency step or the dwell time can be varied. But, increasing the frequency step affects the scanning time range performance, and decreasing the dwell time reduces SNR. In this paper, we introduce a novel multi-carrier radar technique, the step frequency multi-carrier (SFMC) which sends multiple CW signals simultaneously to speed up the scanning operation, where no reduction of the frequency step and the dwell time is required. In this paper, we apply the orthogonal frequency division multiplexing technique to the simultaneous sending of multiple CW signals. The suggested technique is in the category of the stepped-frequency GPR in that they are based on the frequency domain measurement. They have theoretically almost the same accuracy and SNR. But the scanning time of the suggested technique is incomparably fast than stepped-frequency GPR; hundreds of CW signals can be radiated at one time. To get the nice property, we need to pay additional signal processing process for it. In this paper, we handle the signal processing about impairments such as DC frequency, phase discontinuity, channel estimation, and frequency-edge non-linearity problem. Some simulation and experimental results are shown to address the impairments and performance of the suggested technique.

  1. Postural instability in Parkinson Disease: to step or not to step.

    PubMed

    Kimmell, Kristopher; Pulusu, Vinay K; Bharucha, Kersi J; Ross, Elliott D

    2015-10-15

    Postural instability is a key feature of Parkinson Disease that is associated with falls and morbidity. We designed a pull apparatus to quantitatively measure the force needed to pull subjects off-balance. Thirteen Controls and eight individuals with Parkinson Disease (PD) were evaluated. All individuals with PD reported subjective symptoms of postural instability and were symptomatic for approximately 9.4years when tested. No significant differences were found between Controls and PD subjects in the magnitude of force required to pull them off-balance. None of the Controls fell and all took a step into the direction of pull to maintain their balance. 59% of the time PD subjects fell because they did not take a step in the direction of pull to maintain their center of mass (COM) over their feet, thus indicating a deficiency in postural reflexes. If they fell on the first pull, PD subjects did not show a learning effect when pulled multiple times in the same direction. The utility of the Pull Test to detect postural instability is related to the subject's behavioral response, not the force needed to pull them off balance. Our findings may also help explain certain features of the PD gait as an attempt by subjects to avoid postural instability by not placing their COM in gravitationally unstable positions.

  2. Cyberbullying among adolescents: the role of affective and cognitive empathy, and gender.

    PubMed

    Ang, Rebecca P; Goh, Dion H

    2010-08-01

    The purpose of the study was to examine the association between affective empathy, cognitive empathy, and gender on cyberbullying among adolescents. Participants were 396 adolescents from Singapore with age ranging from 12 to 18 years. Adolescents responded to a survey with scales measuring both affective and cognitive empathy, and cyberbullying behavior. A three-step hierarchical multiple regression analysis was used with cyberbullying scores as the dependent variable. Gender was dummy coded and both affective and cognitive empathy were centered using the sample mean prior to creating interaction terms and entering them into the regression equations. The testing, probing and interpretation of interaction effects followed established statistical procedures. Results from hierarchical multiple regression analysis indicated a significant three-way interaction. At low affective empathy, both boys and girls who also had low cognitive empathy had higher scores on cyberbullying than those who had high cognitive empathy. This pattern of results was similarly found for boys at high affective empathy. However, for girls, high or low levels of cognitive empathy resulted in similar levels of cyberbullying. Implications of these findings include the need for empathy training and the importance of positive caregiver-child relationships in reducing cyberbullying behavior among adolescents.

  3. Multiple epiphyseal dysplasia

    PubMed Central

    2009-01-01

    Background Multiple epiphyseal dysplasia (MED) is a common genetically and clinically heterogeneous skeletal dysplasia characterized by early-onset osteoarthritis, mainly in the hip and knee, and mild-to-moderate short stature. Here we report on a 6-generation MED family with 17 affected members. Method The clinical and radiographic data on the 12 affected members still living were scrutinized. A structured inquiry comprising state of health and MED-related symptoms since birth up to the present time and the osteoarthritis outcome (KOOS) questionnaire were sent to all living family members with MED. The 5 known gene loci for autosomal dominant MED were analyzed for linkage, using fluorescence-labeled microsatellite markers. Linkage was ascertained with markers close to the COL9A2 gene, which was analyzed for mutations by sequencing. Results We identified an exon 3 donor splice mutation in the COL9A2 gene in all affected family members. Clinical, radiographic, and questionnaire data from affected family members suggested that MED caused by COL9A2 mutations starts in early childhood with knee pain accompanied by delayed ossification of femoral epiphyses. The disease then either stabilizes during puberty or progresses with additional joints becoming affected; joint surgery might be necessary. The progression of the disease also affects muscles, with increasing atrophy, resulting in muscle fatigue and pain. Muscular atrophy has not been reported earlier in cases with COL9A2 mutations. Interpretation In a patient with clinically suspected or verified MED, it is important to perform DNA-based analysis to identify a possible disease-causing mutation. This information can be used to carry out genetic risk assessment of other family members and to achieve an early and correct diagnosis in the children. PMID:19995321

  4. Executive Functions Underlying Multiplicative Reasoning: Problem Type Matters

    ERIC Educational Resources Information Center

    Agostino, Alba; Johnson, Janice; Pascual-Leone, Juan

    2010-01-01

    We investigated the extent to which inhibition, updating, shifting, and mental-attentional capacity ("M"-capacity) contribute to children's ability to solve multiplication word problems. A total of 155 children in Grades 3-6 (8- to 13-year-olds) completed a set of multiplication word problems at two levels of difficulty: one-step and multiple-step…

  5. Stepping Up to Science and Math

    ERIC Educational Resources Information Center

    Goldston, Dee

    2004-01-01

    "Stepping Up to Science and Math" invites teachers to step back and rethink the way they teach both of these essential subjects. Then it illustrates how teachers can step up the pace with Standards-based activities that make learning more effective and efficient. (New lessons featuring gummy worms, school buses, or the planet Mars help teachers…

  6. STEPS: Moving from Welfare to Work.

    ERIC Educational Resources Information Center

    Vail, Ann; Cummings, Merrilyn; Kratzer, Connie; Galindo, Vickie

    Cooperative extension service faculty at New Mexico State University started the Steps to Employment and Personal Success (STEPS) program to help Temporary Assistance for Needy Families (TANF) clients qualify for and maintain full-time employment and strengthen their families for long-term success. Clients are referred to STEPS by New Mexico…

  7. CAD for 4-step braided fabric composites

    SciTech Connect

    Pandey, R.; Hahn, H.T.

    1994-12-31

    A general framework is provided to predict thermoelastic properties of three dimensional 4-step braided fabric composites. Three key steps involved are (1) the development of a CAD model for yarn architecture, (2) the extraction of a unit cell (3) the prediction of the thermoelastic properties based on micromechanics. Main features of each step are summarized and experimental correlations are provided in the paper.

  8. 7 CFR 60.122 - Production step.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Production step. 60.122 Section 60.122 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... FOR FISH AND SHELLFISH General Provisions Definitions § 60.122 Production step. Production step...

  9. 7 CFR 65.230 - Production step.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Production step. 65.230 Section 65.230 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards..., PEANUTS, AND GINSENG General Provisions Definitions § 65.230 Production step. Production step means,...

  10. 7 CFR 65.230 - Production step.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Production step. 65.230 Section 65.230 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards..., PEANUTS, AND GINSENG General Provisions Definitions § 65.230 Production step. Production step means,...

  11. The Complexity of One-Step Equations

    ERIC Educational Resources Information Center

    Ngu, Bing

    2014-01-01

    An analysis of one-step equations from a cognitive load theory perspective uncovers variation within one-step equations. The complexity of one-step equations arises from the element interactivity across the operational and relational lines. The higher the number of operational and relational lines, the greater the complexity of the equations.…

  12. Ten steps to successful software process improvement

    NASA Technical Reports Server (NTRS)

    Kandt, R. K.

    2003-01-01

    This paper identifies ten steps for managing change that address organizational and cultural issues. Four of these steps are critical, that if not done, will almost guarantee failure. This ten-step program emphasizes the alignment of business goals, change process goals, and the work performed by the employees of an organization.

  13. 15 CFR 732.1 - Steps overview.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE EXPORT ADMINISTRATION REGULATIONS STEPS FOR USING THE EAR § 732.1 Steps overview. (a)(1) Introduction. In this part, references to the EAR are references to 15... EAR by listing logical steps in § 732.2 through § 732.5 of this part that you can take in...

  14. 15 CFR 732.1 - Steps overview.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE EXPORT ADMINISTRATION REGULATIONS STEPS FOR USING THE EAR § 732.1 Steps overview. (a)(1) Introduction. In this part, references to the EAR are references to 15... EAR by listing logical steps in § 732.2 through § 732.5 of this part that you can take in...

  15. 15 CFR 732.1 - Steps overview.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE EXPORT ADMINISTRATION REGULATIONS STEPS FOR USING THE EAR § 732.1 Steps overview. (a)(1) Introduction. In this part, references to the EAR are references to 15... EAR by listing logical steps in § 732.2 through § 732.5 of this part that you can take in...

  16. 15 CFR 732.1 - Steps overview.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE EXPORT ADMINISTRATION REGULATIONS STEPS FOR USING THE EAR § 732.1 Steps overview. (a)(1) Introduction. In this part, references to the EAR are references to 15... EAR by listing logical steps in § 732.2 through § 732.5 of this part that you can take in...

  17. 15 CFR 732.1 - Steps overview.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE EXPORT ADMINISTRATION REGULATIONS STEPS FOR USING THE EAR § 732.1 Steps overview. (a)(1) Introduction. In this part, references to the EAR are references to 15... EAR by listing logical steps in § 732.2 through § 732.5 of this part that you can take in...

  18. Albumin and multiple sclerosis.

    PubMed

    LeVine, Steven M

    2016-04-12

    Leakage of the blood-brain barrier (BBB) is a common pathological feature in multiple sclerosis (MS). Following a breach of the BBB, albumin, the most abundant protein in plasma, gains access to CNS tissue where it is exposed to an inflammatory milieu and tissue damage, e.g., demyelination. Once in the CNS, albumin can participate in protective mechanisms. For example, due to its high concentration and molecular properties, albumin becomes a target for oxidation and nitration reactions. Furthermore, albumin binds metals and heme thereby limiting their ability to produce reactive oxygen and reactive nitrogen species. Albumin also has the potential to worsen disease. Similar to pathogenic processes that occur during epilepsy, extravasated albumin could induce the expression of proinflammatory cytokines and affect the ability of astrocytes to maintain potassium homeostasis thereby possibly making neurons more vulnerable to glutamate exicitotoxicity, which is thought to be a pathogenic mechanism in MS. The albumin quotient, albumin in cerebrospinal fluid (CSF)/albumin in serum, is used as a measure of blood-CSF barrier dysfunction in MS, but it may be inaccurate since albumin levels in the CSF can be influenced by multiple factors including: 1) albumin becomes proteolytically cleaved during disease, 2) extravasated albumin is taken up by macrophages, microglia, and astrocytes, and 3) the location of BBB damage affects the entry of extravasated albumin into ventricular CSF. A discussion of the roles that albumin performs during MS is put forth.

  19. Childhood Multiple Sclerosis: A Review

    ERIC Educational Resources Information Center

    Waldman, Amy; O'Connor, Erin; Tennekoon, Gihan

    2006-01-01

    Multiple sclerosis (MS) is an autoimmune demyelinating disorder of the central nervous system (CNS) that is increasingly recognized as a disease that affects children. Similar to adult-onset MS, children present with visual and sensory complaints, as well as weakness, spasticity, and ataxia. A lumbar puncture can be helpful in diagnosing MS when…

  20. STEP Tether Dynamics Preliminary Analysis

    NASA Technical Reports Server (NTRS)

    Glaese, John R.

    2000-01-01

    The General Tethered Object Simulation System (GTOSS) has been successfully converted to the PC environment. GTOSS has been run under Microsoft Windows 95, 98 and NT4.0 with no problems noted. Adaptation to the PC environment and definition of the 3 three body configuration required resizing some of the GTOSS internal data arrays. To allow studies of the tether dynamics accompanying electrodynamic thrust, a tether current flow model has also been developed for GTOSS. This model includes effects due to the earth's magnetic field and ionosphere, tether conductivity, temperature, motion, shape and available power. Sample cases have been defined for a proposed STEP-AIRSEDS (Space Transfer using Electrodynamic Propulsion-The Michigan Technic Corporation proposed tether missions for commercial applications) three body configuration. This required definition of a 6th power scenario for GTOSS. This power scenario allows a user to specify whether orbit raising or orbit lowering is to be performed by selecting the number of the tether. Orbit raising and orbit lowering sample cases have been run successfully. Results from these runs have been included in this report. Results have only been generated so far for a three body configuration. Only point end masses have been represented. No attitude dynamics have been included. Initial results suggest that tether current can have significant and detrimental effects on tether dynamics and provisions will have to be made for control of it. This control will have to be considered in connection with desired target orbits for electrodynamic thrusting, as well as end body attitude control, momentum management of proposed control moment gyros, solar array pointing. All of these items will interact and thus, any system simulation will have to have each of these effects modeled in sufficient detail to display these interactions.

  1. First steps towards a scatterometry reference standard

    NASA Astrophysics Data System (ADS)

    Bodermann, Bernd; Hansen, Poul-Erik; Burger, Sven; Henn, Mark-Alexander; Gross, Hermann; Bär, Markus; Scholze, Frank; Endres, Johannes; Wurm, Matthias

    2012-10-01

    Supported by the European Commission and EURAMET, a consortium of 10 participants from national metrology institutes, universities and companies has recently started a joint research project with the aim of overcoming current challenges in optical scatterometry for traceable linewidth metrology and to establish scatterometry as a traceable and absolute metrological method for dimensional measurements. This requires a thorough investigation of the influence of all significant sample, tool and data analysis parameters, which affect the scatterometric measurement results. For this purpose and to improve the tool matching between scatterometers, CD-SEMs and CD-AFMs, experimental and modelling methods will be enhanced. The different scatterometry methods will be compared with each other and with specially adapted atomic force microscopy (AFM) and scanning electron microscopy (SEM) measurement systems. Additionally novel methods for sophisticated data analysis will be developed and investigated to reach significant reductions of the measurement uncertainties in critical dimension (CD) metrology. To transfer traceability to industrial applications of scatterometry an important step and one final goal of this project is the realisation of different waferbased reference standard materials for calibration of scatterometers. The approaches to reach these goals and first design considerations and preliminary specification of the scatterometry standards are presented and discussed.

  2. Solar array stepping to minimize array excitation

    NASA Technical Reports Server (NTRS)

    Bhat, Mahabaleshwar K. P. (Inventor); Liu, Tung Y. (Inventor); Plescia, Carl T. (Inventor)

    1989-01-01

    Mechanical oscillations of a mechanism containing a stepper motor, such as a solar-array powered spacecraft, are reduced and minimized by the execution of step movements in pairs of steps, the period between steps being equal to one-half of the period of torsional oscillation of the mechanism. Each pair of steps is repeated at needed intervals to maintain desired continuous movement of the portion of elements to be moved, such as the solar array of a spacecraft. In order to account for uncertainty as well as slow change in the period of torsional oscillation, a command unit may be provided for varying the interval between steps in a pair.

  3. The Sinorhizobium meliloti stringent response affects multiple aspects of symbiosis.

    PubMed

    Wells, Derek H; Long, Sharon R

    2002-03-01

    Sinorhizobium meliloti and host legumes enter into a nitrogen-fixing, symbiotic relationship triggered by an exchange of signals between bacteria and plant. S. meliloti produces Nod factor, which elicits the formation of nodules on plant roots, and succinoglycan, an exopolysaccharide that allows for bacterial invasion and colonization of the host. The biosynthesis of these molecules is well defined, but the specific regulation of these compounds is not completely understood. Bacteria control complex regulatory networks by the production of ppGpp, the effector molecule of the stringent response, which induces physiological change in response to adverse growth conditions and can also control bacterial development and virulence. Through detailed analysis of an S. meliloti mutant incapable of producing ppGpp, we show that the stringent response is required for nodule formation and regulates the production of succinoglycan. Although it remains unknown whether these phenotypes are connected, we have isolated suppressor strains that restore both defects and potentially identify key downstream regulatory genes. These results indicate that the S. meliloti stringent response has roles in both succinoglycan production and nodule formation and, more importantly, that control of bacterial physiology in response to the plant and surrounding environment is critical to the establishment of a successful symbiosis.

  4. Many Seniors Take Multiple Meds That Can Affect the Brain

    MedlinePlus

    ... particular concern due to the increased risk of death, the researchers explained. "The rise we saw in these data may reflect the increased willingness of seniors to seek help and accept medication for mental health conditions -- but it's also concerning because of the ...

  5. Multiple sclerosis - resources

    MedlinePlus

    Resources - multiple sclerosis ... The following organizations provide information on multiple sclerosis : Multiple Sclerosis Foundation -- www.msfocus.org National Institute of Neurological Disorders and Stroke -- www.ninds.nih.gov/disorders/multiple_sclerosis National ...

  6. The discriminant capabilities of stability measures, trunk kinematics, and step kinematics in classifying successful and failed compensatory stepping responses by young adults.

    PubMed

    Crenshaw, Jeremy R; Rosenblatt, Noah J; Hurt, Christopher P; Grabiner, Mark D

    2012-01-03

    This study evaluated the discriminant capability of stability measures, trunk kinematics, and step kinematics to classify successful and failed compensatory stepping responses. In addition, the shared variance between stability measures, step kinematics, and trunk kinematics is reported. The stability measures included the anteroposterior distance (d) between the body center of mass and the stepping limb toe, the margin of stability (MOS), as well as time-to-boundary considering velocity (TTB(v)), velocity and acceleration (TTB(a)), and MOS (TTB(MOS)). Kinematic measures included trunk flexion angle and angular velocity, step length, and the time after disturbance onset of recovery step completion. Fourteen young adults stood on a treadmill that delivered surface accelerations necessitating multiple forward compensatory steps. Thirteen subjects fell from an initial disturbance, but recovered from a second, identical disturbance. Trunk flexion velocity at completion of the first recovery step and trunk flexion angle at completion of the second step had the greatest overall classification of all measures (92.3%). TTB(v) and TTB(a) at completion of both steps had the greatest classification accuracy of all stability measures (80.8%). The length of the first recovery step (r ≤ 0.70) and trunk flexion angle at completion of the second recovery step (r ≤ -0.54) had the largest correlations with stability measures. Although TTB(v) and TTB(a) demonstrated somewhat smaller discriminant capabilities than trunk kinematics, the small correlations between these stability measures and trunk kinematics (|r| ≤ 0.52) suggest that they reflect two important, yet different, aspects of a compensatory stepping response.

  7. Positive everyday experiences interact with social support to predict depression in multiple sclerosis.

    PubMed

    Vargas, Gray A; Arnett, Peter A

    2010-11-01

    Both social support and stress predict depression in multiple sclerosis (MS) patients. Little work has been done on the relationship between positive life experiences and depression in this group. Ninety MS patients completed the Social Support Questionnaire (SSQ), the Hassles and Uplifts Scale (HUS), the Chicago Multiscale Depression Inventory (CMDI), and the Affective Reading Span Task (ARST). The Expanded Disability Status Scale (EDSS) was also used. Separate regression analyses were conducted with the EDSS entered at step 1, ARST memory bias score at step 2, SSQ at step 3, either Hassles or Uplifts at step 4, and the interaction term at step 5 to predict depression. Uplifts interacted significantly with social support to predict depression, but hassles did not. After considering disability level, memory bias, and social support and uplifts main effects, the interaction of uplifts and social support accounted for nearly 5% independent variance in depression (p < .05). These results suggest that the absence of uplifts, combined with low levels of social support, is related to depression in MS patients. More generally, these data indicate that it is important to study the absence of positive experiences along with stress and negative experiences in this population.

  8. Composite-step product methods for solving nonsymmetric linear systems

    SciTech Connect

    Chan, T.F.; Szeto, T.

    1994-12-31

    The Biconjugate Gradient (BCG) algorithm is the {open_quotes}natural{close_quotes} generalization of the classical Conjugate Gradient method to nonsymmetric linear systems. It is an attractive method because of its simplicity and its good convergence properties. Unfortunately, BCG suffers from two kinds of breakdowns (divisions by 0): one due to the non-existence of the residual polynomial, and the other due to a breakdown in the recurrence relationship used. There are many look-ahead techniques in existence which are designed to handle these breakdowns. Although the step size needed to overcome an exact breakdown can be computed in principle, these methods can unfortunately be quite complicated for handling near breakdowns since the sizes of the look-ahead steps are variable (indeed, the breakdowns can be incurable). Recently, Bank and Chan introduced the Composite Step Biconjugate Gradient (CSBCG) algorithm, an alternative which cures only the first of the two breakdowns mentioned by skipping over steps for which the BCG iterate is not defined. This is done with a simple modification of BCG which needs only a maximum look-ahead step size of 2 to eliminate the (near) breakdown and to smooth the sometimes erratic convergence of BCG. Thus, instead of a more complicated (but less prone to breakdown) version, CSBCG cures only one kind of breakdown, but does so with a minimal modification to the usual implementation of BCG in the hope that its empirically observed stability will be inherited. The authors note, then, that the Composite Step idea can be incorporated anywhere the BCG polynomial is used; in particular, in product methods such as CGS, Bi-CGSTAB, and TFQMR. Doing this not only cures the breakdown mentioned above, but also takes on the advantages of these product methods, namely, no multiplications by the transpose matrix and a faster convergence rate than BCG.

  9. Improving Multiple Fault Diagnosability using Possible Conflicts

    NASA Technical Reports Server (NTRS)

    Daigle, Matthew J.; Bregon, Anibal; Biswas, Gautam; Koutsoukos, Xenofon; Pulido, Belarmino

    2012-01-01

    Multiple fault diagnosis is a difficult problem for dynamic systems. Due to fault masking, compensation, and relative time of fault occurrence, multiple faults can manifest in many different ways as observable fault signature sequences. This decreases diagnosability of multiple faults, and therefore leads to a loss in effectiveness of the fault isolation step. We develop a qualitative, event-based, multiple fault isolation framework, and derive several notions of multiple fault diagnosability. We show that using Possible Conflicts, a model decomposition technique that decouples faults from residuals, we can significantly improve the diagnosability of multiple faults compared to an approach using a single global model. We demonstrate these concepts and provide results using a multi-tank system as a case study.

  10. Maximal lateral reaching distance on the affected side using the multi-directional reach test in persons with stroke

    PubMed Central

    Hwang, Won-Jeong; Kim, Jung-Hyun; Jeon, Seo-Hyun; Chung, Yijung

    2015-01-01

    [Purpose] This study aimed to examine the relationship between maximal lateral reaching distance on the affected side and weight shifting using the Multi-directional Reach Test in persons with stoke. [Subjects] Fifty-one chronic stroke participants were recruited from two rehabilitation hospitals. This study administered the Berg Balance Scale, Timed Up-and-Go, Trunk Impairment Scale, Modified Barthel Index and measured different maximal reaching distances. [Results] The maximal lateral reaching distance on the affected side was correlated with the BBS (r=0.571), TUG (r=−0.478), TIS (r=0.561), and MBI scores (r=0.499), the lateral reaching distance in all directions on the non-affected side (r=0.785), the maximal backward reaching distance (r=0.723), and the maximal forward reaching distance (r=0.673). The maximal reaching distance on the affected side was also affected by that on the non-affected side, in addition to the maximal backward reaching distance and MBI score. The final step model of stepwise multiple regression was explained 69.5%. [Conclusion] Maximal lateral reaching distance on the affected side as determined by the Multi-directional Reach Test is a good method of assessing functional performance in stroke patients. Data regarding maximal reaching distance on the non-affected side can be used to measure functional impairment on the affected side in clinical settings. PMID:26504275

  11. Perturbations of ground support alter posture and locomotion coupling during step initiation in Parkinson's disease.

    PubMed

    Rogers, Mark W; Hilliard, Marjorie Johnson; Martinez, Katherine M; Zhang, Yunhui; Simuni, Tanya; Mille, Marie-Laure

    2011-02-01

    During the initiation of stepping, anticipatory postural adjustments (APAs) for lateral weight transfer and propulsion normally precede the onset of locomotion. In Parkinson's disease (PD), impaired step initiation typically involves altered APA ground force production with delayed step onset and deficits in stepping performance. If, as in stance and gait, sensory information about lower limb load is important for the control of stepping, then perturbations influencing loading conditions could affect the step initiation process. This study investigated the influence of changes in lower limb loading during step initiation in patients with PD and healthy control subjects. Participants performed rapid self-triggered step initiation with the impending single stance limb positioned over a pneumatically actuated platform. In perturbation trials, the stance limb ground support surface was either moved vertically downward (DROP) or upward (ELEVATE) by 1.5 cm shortly after the onset of the APA phase. Overall, PD patients demonstrated a longer APA duration, longer time to first step onset, and slower step speed than controls. In both groups, the DROP perturbation reinforced the intended APA kinetic changes for lateral weight transfer and resulted in a significant reduction in APA duration, increase in peak amplitude, and earlier time to first step onset compared with other conditions. During ELEVATE trials that opposed the intended weight transfer forces both groups rapidly adapted their stepping to preserve standing stability by decreasing step length and duration, and increasing step height and foot placement laterally. The findings suggested that sensory information associated with limb load and/or foot pressure modulates the spatial and temporal parameters of posture and locomotion components of step initiation in interaction with a centrally generated feedforward mode of neural control. Moreover, impaired step initiation in PD may at least acutely be enhanced by

  12. Convergence of step-by-step methods for non-linear integro-differential equations.

    NASA Technical Reports Server (NTRS)

    Mocarsky, W. L.

    1971-01-01

    The theory of consistent step-by-step methods for solving Volterra integral equations is extended to nonsingular Volterra integro-differential equations. It is shown that standard step-by-step algorithms for these more general equations are convergent. Several numerical examples are included.

  13. A Step-by-Step Teaching Technique for Teachers with Adult Students of Mathematics

    ERIC Educational Resources Information Center

    McDonald, Betty

    2013-01-01

    Step-by-step teaching is a researcher-designed innovative process that takes the adult learner, step-by-step, from his present level of understanding to the required level. The technique is based on well-researched and accepted pedagogical practices set in their psychological, sociological, and andragogical perspectives. Using a convenience sample…

  14. Steps Toward Optimal Competitive Scheduling

    NASA Technical Reports Server (NTRS)

    Frank, Jeremy; Crawford, James; Khatib, Lina; Brafman, Ronen

    2006-01-01

    This paper is concerned with the problem of allocating a unit capacity resource to multiple users within a pre-defined time period. The resource is indivisible, so that at most one user can use it at each time instance. However, different users may use it at different times. The users have independent, se@sh preferences for when and for how long they are allocated this resource. Thus, they value different resource access durations differently, and they value different time slots differently. We seek an optimal allocation schedule for this resource. This problem arises in many institutional settings where, e.g., different departments, agencies, or personal, compete for a single resource. We are particularly motivated by the problem of scheduling NASA's Deep Space Satellite Network (DSN) among different users within NASA. Access to DSN is needed for transmitting data from various space missions to Earth. Each mission has different needs for DSN time, depending on satellite and planetary orbits. Typically, the DSN is over-subscribed, in that not all missions will be allocated as much time as they want. This leads to various inefficiencies - missions spend much time and resource lobbying for their time, often exaggerating their needs. NASA, on the other hand, would like to make optimal use of this resource, ensuring that the good for NASA is maximized. This raises the thorny problem of how to measure the utility to NASA of each allocation. In the typical case, it is difficult for the central agency, NASA in our case, to assess the value of each interval to each user - this is really only known to the users who understand their needs. Thus, our problem is more precisely formulated as follows: find an allocation schedule for the resource that maximizes the sum of users preferences, when the preference values are private information of the users. We bypass this problem by making the assumptions that one can assign money to customers. This assumption is reasonable; a

  15. Mixing and Matching Deep-UV Step-and-Scan with I-Line Step and Repeat

    NASA Astrophysics Data System (ADS)

    Sewell, Harry

    1995-12-01

    This paper reviews all the major aspects of successfully implementing a “mix and match” (Deep-UV/I-line, stepper/scanner) strategy. The resolution and linewidth-control limits of I-line are quantified for a number of the process levels and compared with the capabilities of Deep-UV step-and-scan. This analysis predicts the typical mix of steppers and scanners in a 256 MBit production line for 250 nm lithography. A step-by-step procedure to achieve and monitor successful matching is reviewed. The procedure begins by defining a “golden system”, which is used to produce reference wafers for the setup and monitoring of all the systems being mixed and matched. The reference wafers are used to ensure that the pre-aligners of the systems are calibrated and that offsets are adapted to allow the transfer of wafers between systems. The wafers are also used to match both wafer-stage grid and exposure-field distortions. The matching of both wafer-grid and stepper-field distortions are reviewed. The implementation of stage correction-tables is demonstrated. It is indicated that grid matching to better than 10 nm is achievable. It is also indicated that the dynamic scanning of a step-and-scan system allows the monitoring and correction of such typical stepper problems as field magnification and rotation. The critical aspects of multi-field matching between stepper and scanner are analyzed. The key factors that allow the successful overlaying of large, single, scanned fields with multiple, small, stepped fields are reviewed. The total overlay accuracy achieved using step-and-scan, and “mix-and-match” is analyzed and demonstrated.

  16. Multi-step prediction of physiological tremor for robotics applications.

    PubMed

    Veluvolu, K C; Tatinati, S; Hong, S M; Ang, W T

    2013-01-01

    The performance of surgical robotic devices in real-time mainly depends on phase-delay in sensors and filtering process. A phase delay of 16-20 ms is unavoidable in these robotics procedures due to the presence of hardware low pass filter in sensors and pre-filtering required in later stages of cancellation. To overcome this phase delay, we employ multi-step prediction with band limited multiple Fourier linear combiner (BMFLC) and Autoregressive (AR) methods. Results show that the overall accuracy is improved by 60% for tremor estimation compared to single-step prediction methods in the presence of phase delay. Experimental results with the proposed methods for 1-DOF tremor estimation highlight the improvement.

  17. Contribution of lower limb eccentric work and different step responses to balance recovery among older adults.

    PubMed

    Nagano, Hanatsu; Levinger, Pazit; Downie, Calum; Hayes, Alan; Begg, Rezaul

    2015-09-01

    Falls during walking reflect susceptibility to balance loss and the individual's capacity to recover stability. Balance can be recovered using either one step or multiple steps but both responses are impaired with ageing. To investigate older adults' (n=15, 72.5±4.8 yrs) recovery step control a tether-release procedure was devised to induce unanticipated forward balance loss. Three-dimensional position-time data combined with foot-ground reaction forces were used to measure balance recovery. Dependent variables were; margin of stability (MoS) and available response time (ART) for spatial and temporal balance measures in the transverse and sagittal planes; lower limb joint angles and joint negative/positive work; and spatio-temporal gait parameters. Relative to multi-step responses, single-step recovery was more effective in maintaining balance, indicated by greater MoS and longer ART. MoS in the sagittal plane measure and ART in the transverse plane distinguished single step responses from multiple steps. When MoS and ART were negative (<0), balance was not secured and additional steps would be required to establish the new base of support for balance recovery. Single-step responses demonstrated greater step length and velocity and when the recovery foot landed, greater centre of mass downward velocity. Single-step strategies also showed greater ankle dorsiflexion, increased knee maximum flexion and more negative work at the ankle and knee. Collectively these findings suggest that single-step responses are more effective in forward balance recovery by directing falling momentum downward to be absorbed as lower limb eccentric work.

  18. Elastic cost of silicon step rebonding

    NASA Astrophysics Data System (ADS)

    Leroy, F.; Garreau, Y.; Cheynis, F.; Croset, B.; Coati, A.; Müller, P.; Prévot, G.

    2016-01-01

    We study by grazing incidence x-ray diffraction the strain field induced by periodic double steps on a Si(1 1 15) surface that is a vicinal of a Si(001) surface misoriented by 5 .4∘ towards the <110 > direction. The best fit of the experimental structure factors is reached on the basis of the rebonded DB step edge model and the displacement field is well characterized assuming that steps are described by parallel rows of extended buried elastic dipoles. The dipole characteristics are the dipole position with respect to the step edge, the dipole amplitude (2.0 ±0.5 nN), and the lever arm Ω =5 .3∘ and force Φ =3 .7∘ orientations. We show that the dipole is dominated by a large stretch component localized between the lower and the upper corners of the step, which we assign to the presence of the rebonded atom at the step.

  19. Sage Simulation Model for Technology Demonstration Convertor by a Step-by-Step Approach

    NASA Technical Reports Server (NTRS)

    Demko, Rikako; Penswick, L. Barry

    2006-01-01

    The development of a Stirling model using the 1-D Saga design code was completed using a step-by-step approach. This is a method of gradually increasing the complexity of the Saga model while observing the energy balance and energy losses at each step of the development. This step-by-step model development and energy-flow analysis can clarify where the losses occur, their impact, and suggest possible opportunities for design improvement.

  20. Multi-step contrast sensitivity gauge

    DOEpatents

    Quintana, Enrico C; Thompson, Kyle R; Moore, David G; Heister, Jack D; Poland, Richard W; Ellegood, John P; Hodges, George K; Prindville, James E

    2014-10-14

    An X-ray contrast sensitivity gauge is described herein. The contrast sensitivity gauge comprises a plurality of steps of varying thicknesses. Each step in the gauge includes a plurality of recesses of differing depths, wherein the depths are a function of the thickness of their respective step. An X-ray image of the gauge is analyzed to determine a contrast-to-noise ratio of a detector employed to generate the image.

  1. The Hydroacoustics of Beveled Steps and Gaps

    DTIC Science & Technology

    2015-11-01

    to measure and predict the sound radiation from steps and gaps on large pales excited by turbulent boundary layers. Results are given showing the...the last few years there have been some enlightening experimental and numerical studies on the sound radiated by turbulent flow over steps and gaps...used to predict the sound radiated from steps and gaps at full scale. The purpose of this study was to develop these scaling laws by combining the

  2. A vibrators alternation stepping ultrasonic motor.

    PubMed

    Jin, Jiamei; Zhao, Chunsheng

    2006-12-22

    A new concept of a vibrators alternation stepping ultrasonic motor, based on longitudinal vibrations of rectangular Langevin resonators, is presented. The new motor fed by a single-phase resource without feedback is capable of bi-directions step displacements without accumulative displacement error. The step angle is 1.44 degrees, when the 150 grooves on the rotor are used in positioning. The average rotation speed without load in one step is 16.49-14.65 rad/s, and the braking torque is 0.071-0.088 Nm in operating frequency 30 kHz and operation voltage 200 V.

  3. Smart Steps to Sustainability 2.0

    EPA Pesticide Factsheets

    Smart Steps to Sustainability provides small business owners and managers with practical advice and tools to implementsustainable and environmentally-preferable business practices that go beyond compliance.

  4. One step geometrical calibration method for optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Díaz Díaz, Jesús; Stritzel, Jenny; Rahlves, Maik; Majdani, Omid; Reithmeier, Eduard; Ortmaier, Tobias; Roth, Bernhard

    2016-01-01

    We present a novel one-step calibration methodology for geometrical distortion correction for optical coherence tomography (OCT). A calibration standard especially designed for OCT is introduced, which consists of an array of inverse pyramidal structures. The use of multiple landmarks situated on four different height levels on the pyramids allow performing a 3D geometrical calibration. The calibration procedure itself is based on a parametric model of the OCT beam propagation. It is validated by experimental results and enables the reduction of systematic errors by more than one order of magnitude. In future, our results can improve OCT image reconstruction and interpretation for medical applications such as real time monitoring of surgery.

  5. Mixed Mode Matrix Multiplication

    SciTech Connect

    Meng-Shiou Wu; Srinivas Aluru; Ricky A. Kendall

    2004-09-30

    In modern clustering environments where the memory hierarchy has many layers (distributed memory, shared memory layer, cache,...), an important question is how to fully utilize all available resources and identify the most dominant layer in certain computations. When combining algorithms on all layers together, what would be the best method to get the best performance out of all the resources we have? Mixed mode programming model that uses thread programming on the shared memory layer and message passing programming on the distributed memory layer is a method that many researchers are using to utilize the memory resources. In this paper, they take an algorithmic approach that uses matrix multiplication as a tool to show how cache algorithms affect the performance of both shared memory and distributed memory algorithms. They show that with good underlying cache algorithm, overall performance is stable. When underlying cache algorithm is bad, superlinear speedup may occur, and an increasing number of threads may also improve performance.

  6. Multiple Sclerosis and its Management

    PubMed Central

    Weinshenker, Brian

    1992-01-01

    Multiple sclerosis, the most common disabling disease of the central nervous system affecting young adults, is diagnosed primarily from a history of typical relapsing and remitting white matter symptoms supported by objective signs. Multiple sclerosis may present in more insidious ways or may be mimicked by other diseases, which seemingly satisfy the diagnostic criteria of dissemination in time and space. Patients need psychological support to deal with an uncertain future. A multidisciplinary team approach can best manage both acute temporary disability and, often later, progressive physical and occasionally mental disability. ImagesFigures 1-3 PMID:21221279

  7. Body composition in multiple sclerosis

    PubMed Central

    Dionyssiotis, Y

    2013-01-01

    Multiple sclerosis affects central nervous system leading to disability. Among other complications the deterioration of body composition is usually neglected and increases the risk for diseases such as coronary heart disease, non-insulin dependent diabetes mellitus, lipid abnormalities and bone loss leading to fractures in this population. Body mass index values, the effect of spasticity, the increased number of drugs used and the relationship between skeletal muscle and bone which interacts with impaired motor function leading to body composition alterations in multiple sclerosis are reviewed. PMID:23935336

  8. Kinematic analysis of step ascent among patients with central visual field loss.

    PubMed

    Timmis, Matthew A; Scarfe, Amy C; Tabrett, Daryl R; Pardhan, Shahina

    2014-01-01

    Vision is of paramount importance in regulating adaptive gait. Using three-dimensional motion analysis, the current study investigated how central visual field loss (CFL) affects step ascent. Ten patients with chronic CFL (77 ± 10 years) and 13 visual normal participants (72 ± 6 years) walked up to and ascended a single step (of varying height). Movement kinematics assessed the period immediately prior to and during step ascent. Compared to visual normal participants, patients with CFL exhibited a lower lead foot horizontal crossing velocity, increased lead limb swing time and increased head flexion (looking down at more immediate areas of the ground/step). They also took longer to initiate the step up, transfer weight to the lead foot upon landing on the upper level and increased trail limb swing time when negotiating the medium and high step height. Increased variability was also shown in a number of dependent measures. Data indicate that during step ascent, patients with CFL exhibit a cautious stepping strategy when compared to visual normal participants. This cautious strategy becomes increasingly evident when negotiating higher step heights, as shown by an increased planning time prior to entering the relatively unstable period of single support during the step up. The increased variability among CFL patients increases their likelihood of experiencing dynamic instability and falling during step ascent.

  9. Morphology of step-pools in a wilderness headwater stream: The importance of standardizing geomorphic measurements

    NASA Astrophysics Data System (ADS)

    Nickolotsky, Aaron; Pavlowsky, Robert T.

    2007-01-01

    The morphology of step-pools and cascades reflect the geological and climatic factors affecting channels in mountain watersheds. This study uses longitudinal and cross-section surveys to describe a headwater stream in the Boston Mountains of the Ozarks Plateau region in Arkansas and develop morphological relationships for comparisons with other regions. In the Bowers Hollow Creek watershed (3.5 km 2), located within the boundaries of the Upper Buffalo Wilderness Area, step height and wavelength relationships are generally similar to those reported from other regions. Step-pool reaches were widely distributed in a discontinuous manner throughout the watershed. Average values of the sampled reaches are: reach slopes, 0.105 m/m; width, 6.10 m; crest particle sizes, 440 mm; step heights, 0.87 m; and step wavelengths, 6.62 m. The mean step steepness for the watershed was 0.13, whereas the mean length of a reach step to height ratio was 9:1. A comparison of morphological definitions found that the values of step height and steepness can vary by > 30% according to how step parameters are defined. Step height is particularly sensitive; thus, comparison of step height-based relationships from published data requires great care.

  10. Understanding of Multiplicative Contexts Involving Fractions.

    ERIC Educational Resources Information Center

    Hardiman, Pamela Thibodeau; Mestre, Jose P.

    Numerous studies indicate that performance in solving single step multiplicative word problems is influenced by both problem structure and the types of numbers involved in the problem. For example, including numbers less than one often increases the difficulty of a problem. What remains unclear is how problem structure and number type interact in…

  11. Electron Diffraction from Surfaces with Atomic Steps

    NASA Astrophysics Data System (ADS)

    Lent, Craig Stanley

    The presence of atomic steps on solid surfaces is important in catalysis, crystal growth and dissolution processes. Because of the decreased coordination of atoms at step edges, these sites are frequently more reactive than others. Knowledge of the step distribution on the surface is required in order to adequately incorporate the effects of steps in models of physical processes. We examine the sensitivity of electron diffraction, particularly Reflection High Energy Electron Diffraction (RHEED), to the atomic step distribution on the surface. The RHEED instrument response length is considerably larger than other diffraction instruments, making it particularly suited for studying surface steps. Several calculations are presented to assess the effect of various step distributions on the intensity profiles of diffracted beams at various angles of incidence. The geometric distribution of steps corresponds to the limit of no interactions between step edges. A Markov matrix method of calculating the diffracted intensity from a geometric distribution of surface steps is presented. This reduces the calculation to a simple eigenvalue problem. The diffracted intensity profile is the sum of a sharp central spike, corresponding to the instrument response function, and several Lorenztians, whose widths are related to the eigenvalues of the matrix describing the distribution. The Markov approach also leads to the important distinction between reversible and irreversible step distributions. More general calculations, valid for any step distribution reveal that the separation into a central spike and step-broadened terms is retained. The shapes of the broad terms depend on the details of the distribution. The relative contributions of the step-broadened parts and the central spike vary as incident angle is changed and depend on the surface coverage. RHEED beam profiles have been measured from surfaces prepared by Molecular Beam Epitaxy. Submonolayer amounts of GaAs and AlAs were

  12. Assessing the Effectiveness of First Step to Success: Are Short-Term Results the First Step to Long-Term Behavioral Improvements?

    ERIC Educational Resources Information Center

    Sumi, W. Carl; Woodbridge, Michelle W.; Javitz, Harold S.; Thornton, S. Patrick; Wagner, Mary; Rouspil, Kristen; Yu, Jennifer W.; Seeley, John R.; Walker, Hill M.; Golly, Annemieke; Small, Jason W.; Feil, Edward G.; Severson, Herbert H.

    2013-01-01

    This article reports on the effectiveness of First Step to Success, a secondary-level intervention appropriate for students in early elementary school who experience moderate to severe behavior problems and are at risk for academic failure. The authors demonstrate the intervention's short-term effects on multiple behavioral and academic outcomes…

  13. Spatial layout affects speed discrimination

    NASA Technical Reports Server (NTRS)

    Verghese, P.; Stone, L. S.

    1997-01-01

    We address a surprising result in a previous study of speed discrimination with multiple moving gratings: discrimination thresholds decreased when the number of stimuli was increased, but remained unchanged when the area of a single stimulus was increased [Verghese & Stone (1995). Vision Research, 35, 2811-2823]. In this study, we manipulated the spatial- and phase relationship between multiple grating patches to determine their effect on speed discrimination thresholds. In a fusion experiment, we merged multiple stimulus patches, in stages, into a single patch. Thresholds increased as the patches were brought closer and their phase relationship was adjusted to be consistent with a single patch. Thresholds increased further still as these patches were fused into a single patch. In a fission experiment, we divided a single large patch into multiple patches by superimposing a cross with luminance equal to that of the background. Thresholds decreased as the large patch was divided into quadrants and decreased further as the quadrants were maximally separated. However, when the cross luminance was darker than the background, it was perceived as an occluder and thresholds, on average, were unchanged from that for the single large patch. A control experiment shows that the observed trend in discrimination thresholds is not due to the differences in perceived speed of the stimuli. These results suggest that the parsing of the visual image into entities affects the combination of speed information across space, and that each discrete entity effectively provides a single independent estimate of speed.

  14. Deviation of sliding drops at a chemical step.

    PubMed

    Semprebon, Ciro; Varagnolo, Silvia; Filippi, Daniele; Perlini, Luca; Pierno, Matteo; Brinkmann, Martin; Mistura, Giampaolo

    2016-10-12

    The motion of partially wetting liquid drops in contact with a solid surface is strongly affected by contact angle hysteresis and interfacial pinning. However, the majority of models proposed for drops sliding over chemical surface patterns consistently neglect the difference between advancing and receding contact angles. In this article, we present a joint experimental and numerical study of the interaction of gravity-driven drops with a chemical step formed at the junction between a hydrophilic and a hydrophobic region. It demonstrates the strong impact of a contact angle hysteresis contrast on the motion of drops at a linear chemical step. Surprisingly, the smallest driving force required to drag the drop across the step onto the lower hydrophobic surface is not observed at a right angle of incidence. Our model reveals that the non-monotonous response of this passive drop 'filter' is solely due to the higher advancing contact angle on the lower surface, and creates an instance where drop motion is affected by dissipation at the contact line rather than by surface energy.

  15. Step energy and step interactions on the reconstructed GaAs(001) surface

    NASA Astrophysics Data System (ADS)

    Magri, Rita; Gupta, Sanjeev K.; Rosini, Marcello

    2014-09-01

    Using ab initio total energy calculations we have studied the relation between the step atomic configuration and its properties (step energy, donor/acceptor behavior, and step interaction) on a β2(2×4) reconstructed GaAs (001) surface. The results have been tested against the widely used elastic dipole model for the step energy and step interaction considered valid for stress-free surfaces. We have found that acceptor-behaving steps have an attractive interaction and donor-behaving steps have a repulsive interaction in contrast with the elastic dipole model which predicts always a repulsive interaction between like-oriented steps. To account for the attractive interaction we consider the electrostatic dipole interaction having the L-2 scaling with the step distance L and therefore compatible with the standard elastic model. Using a model charge distribution with localized point charges at the step based on the electron counting model we show that the electrostatic step interaction can indeed be generally attractive and of the same order of magnitude of the negative elastic dipole interaction. Our results show however that the usually employed dipole model is unable to account for the repulsive/attractive step interaction between donorlike/acceptorlike steps. Therefore, the ab initio results suggest an important electronic contribution to the step interaction, at least at the short step distances accessible to the first-principles study. Our results explain qualitatively many experimental observations and provide an explanation to the step bunching phenomenon on GaAs(001) induced by doping or by critical growth conditions as due to the stabilization of attractively interacting step structures. These ideas would lead to the development of a bottom-up surface step engineering.

  16. Protein crystallization in low gravity by step gradient diffusion method

    NASA Astrophysics Data System (ADS)

    Sygusch, Jurgen; Coulombe, René; Cassanto, John M.; Sportiello, Michael G.; Todd, Paul

    1996-05-01

    Two-step crystallization experiments were conducted in low gravity employing a liquid-liquid diffusion method in an effort to eliminate problems associated with protein crystal growth under the supersaturating conditions required for nucleation. Experiments were performed in diffusion cells formed by the sliding of blocks on orbit. Step gradient diffusion experiments consisted of first exposing protein solutions in diffusion half-wells for brief periods to initiating buffer solutions of high precipitant concentrations to induce nucleation followed by exposure of the same protein solutions to solutions of lower precipitant concentration to promote growth of induced nuclei into crystals. To avoid convective disturbances that occur when solutions of discrepant densities are interfaced at normal gravity, crystallization of hen egg-white lysozyme and rabbit skeletal muscle aldolase by step gradient diffusion was investigated in low gravity on four NASA space shuttle flights. In general, the largest crystals of both proteins formed at the highest initiating precipitant concentration used, which is consistent with nuclei formation upon brief exposure to high precipitant concentration, and that these nuclei are competent for sustained growth at lower precipitant concentration. The two-step approach dissociates nucleation events from crystal growth allowing parameters affecting nucleation kinetics such as time, precipitant concentration and temperature of nucleation to be varied separately from conditions used for post-nucleation growth.

  17. Multiple trellis coded modulation

    NASA Technical Reports Server (NTRS)

    Simon, Marvin K. (Inventor); Divsalar, Dariush (Inventor)

    1990-01-01

    A technique for designing trellis codes to minimize bit error performance for a fading channel. The invention provides a criteria which may be used in the design of such codes which is significantly different from that used for average white Gaussian noise channels. The method of multiple trellis coded modulation of the present invention comprises the steps of: (a) coding b bits of input data into s intermediate outputs; (b) grouping said s intermediate outputs into k groups of s.sub.i intermediate outputs each where the summation of all s.sub.i,s is equal to s and k is equal to at least 2; (c) mapping each of said k groups of intermediate outputs into one of a plurality of symbols in accordance with a plurality of modulation schemes, one for each group such that the first group is mapped in accordance with a first modulation scheme and the second group is mapped in accordance with a second modulation scheme; and (d) outputting each of said symbols to provide k output symbols for each b bits of input data.

  18. Stepped chute training wall height requirements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stepped chutes are commonly used for overtopping protection for embankment dams. Aerated flow is commonly associated with stepped chutes if the chute has sufficient length. The aeration and turbulence of the flow can create a significant amount of splash over the training wall if not appropriately...

  19. Stepped-Pin Clevis Resists Jamming

    NASA Technical Reports Server (NTRS)

    Killgrove, T. O.

    1985-01-01

    Pin modification allows pyrotechnic release devices to operate more smoothly. New clevis pin has stepped diameters to prevent bending as it exits yoke. In contrast, conventional unstepped clevis pin bends and jams as it is withdrawn. Stepped pin design suitable for explosive and possible hammer driven pin sullers.

  20. Inception point for embankment dam stepped spillways

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stepped spillways applied to embankment dams have become a common design practice with the rehabilitation of aging watershed dams, especially those experiencing a hazard classification change from low to high hazard. Previous research on stepped spillways focused on gravity dams where aerated flow ...

  1. Twelve Steps to a Winning First Year

    ERIC Educational Resources Information Center

    Hodges, Karen

    2009-01-01

    This article offers 12 steps to jumpstart a new school librarian's career. Being the information specialist will be both challenging and rewarding as one undertakes a myriad of activities. These 12 steps will help a new school librarian's first year successful.

  2. Student USMLE Step One Preparation and Performance.

    ERIC Educational Resources Information Center

    Zhang, Chi

    This study investigated factors associated with medical students performance on the United States Medical Licensing Examination (USMLE) Step One examination. The USMLE Step One emphasizes basic mechanisms and principles that are typically covered in the first 2 years of medical school. The study examined the relationship among student performance…

  3. Teachers: Recognize Important Steps to Reduce Cheating

    ERIC Educational Resources Information Center

    Supon, Viola

    2008-01-01

    Teachers must walk the steps and live the steps if reducing cheating is going to occur. Teachers begin this process by being cognizant and vigilant relative to administering means of measurement and assigning written work. This process includes skill acquisition in regards to: (1) acknowledging cheating, (2) purposeful planning, (3) electronic…

  4. Smoothing out step changes of LMP

    SciTech Connect

    Li, Fangxing

    2008-08-15

    The locational marginal pricing methodology may lead to a step change when system load grows, creating higher financial risk, especially for small and medium-sized market participants. A proposed continuous LMP method is a straightforward solution to eliminate these step changes when load grows. (author)

  5. Steps in Performing a Communication Audit.

    ERIC Educational Resources Information Center

    Sincoff, Michael Z.; And Others

    This paper develops the step-by-step processes necessary to conduct a communication audit in order to determine the communication effectiveness of an organization. The authors stress the responsibilities of both the audit team and the organization's top management as they interact during progressive phases of the audit. Emphasis is placed on…

  6. Affective processing requires awareness.

    PubMed

    Lähteenmäki, Mikko; Hyönä, Jukka; Koivisto, Mika; Nummenmaa, Lauri

    2015-04-01

    Studies using backward masked emotional stimuli suggest that affective processing may occur outside visual awareness and imply primacy of affective over semantic processing, yet these experiments have not strictly controlled for the participants' awareness of the stimuli. Here we directly compared the primacy of affective versus semantic categorization of biologically relevant stimuli in 5 experiments (n = 178) using explicit (semantic and affective discrimination; Experiments 1-3) and implicit (semantic and affective priming; Experiments 4-5) measures. The same stimuli were used in semantic and affective tasks. Visual awareness was manipulated by varying exposure duration of the masked stimuli, and subjective level of stimulus awareness was measured after each trial using a 4-point perceptual awareness scale. When participants reported no awareness of the stimuli, semantic and affective categorization were at chance level and priming scores did not differ from zero. When participants were even partially aware of the stimuli, (a) both semantic and affective categorization could be performed above chance level with equal accuracy, (b) semantic categorization was faster than affective categorization, and (c) both semantic and affective priming were observed. Affective categorization speed was linearly dependent on semantic categorization speed, suggesting dependence of affective processing on semantic recognition. Manipulations of affective and semantic categorization tasks revealed a hierarchy of categorization operations beginning with basic-level semantic categorization and ending with superordinate level affective categorization. We conclude that both implicit and explicit affective and semantic categorization is dependent on visual awareness, and that affective recognition follows semantic categorization.

  7. Hip joint contact loads in older adults during recovery from forward loss of balance by stepping.

    PubMed

    Graham, David F; Modenese, Luca; Trewartha, Grant; Carty, Christopher P; Constantinou, Maria; Lloyd, David G; Barrett, Rod S

    2016-09-06

    Hip joint contact loads during activities of daily living are not generally considered high enough to cause acute bone or joint injury. However there is some evidence that hip joint loads may be higher in stumble recovery from loss of balance. A common laboratory method used to evaluate balance recovery performance involves suddenly releasing participants from various static forward lean magnitudes (perturbation intensities). Prior studies have shown that when released from the same perturbation intensity, some older adults are able to recover with a single step, whereas others require multiple steps. The main purpose of this study was to use a musculoskeletal model to determine the effect of three balance perturbation intensities and the use of single versus multiple recovery steps on hip joint contact loads during recovery from forward loss of balance in community dwelling older adults (n=76). We also evaluated the association of peak hip contact loads with perturbation intensity, step length and trunk flexion angle at foot contact at each participant׳s maximum recoverable lean angle (MRLA). Peak hip joint contact loads were computed using muscle force estimates obtained using Static Optimisation and increased as lean magnitude was increased and were on average 32% higher for Single Steppers compared to Multiple Steppers. At the MRLA, peak hip contact loads ranged from 4.3 to 12.7 body weights and multiple linear stepwise regression further revealed that initial lean angle, step length and trunk angle at foot contact together explained 27% of the total variance in hip joint contact load. Overall findings indicated that older adults experience peak hip joint contact loads during maximal balance recovery by stepping that in some cases exceeded loads reported to cause mechanical failure of cadaver femurs. While step length and trunk flexion angle are strong predictors of step recovery performance they are at best moderate predictors of peak hip joint loading.

  8. Multiple sclerosis and behavior.

    PubMed

    Pinkston, James B; Kablinger, Anita; Alekseeva, Nadejda

    2007-01-01

    Multiple sclerosis (MS) is one of the most frequently seen neurological causes of progressive disability in early to middle adulthood. The disease is variable in its presentation and course, affects roughly 100-300 per 100,000 persons within the United States alone, and is slightly more common among females than males. MS places substantial burdens on patients, families, and caregivers. It negatively affects cognitive abilities and psychiatric functioning, and can add a notably deleterious effect on a patient's quality of life. This chapter reviews the recent literature on the behavioral manifestations of MS. Cognitive domains discussed include executive functioning, processing speed, attention, learning and memory, language functioning, and visual spatial processing. Some attention will also be paid to differential diagnosis and the cognitive effects of treatment. Psychiatric manifestations are also discussed, including symptoms of depression, bipolar disorder, euphoria, pathological laughter and crying, and psychosis, as well as maladaptive personality traits. Finally, the chapter concludes with a discussion of the effects of MS on quality of life including such areas as fatigue, sexual dysfunction, pain, employment, and cognitive functioning.

  9. Motivational factors and negative affectivity as predictors of alcohol craving.

    PubMed

    Pombo, Samuel; Luísa Figueira, M; Walter, Henriette; Lesch, Otto

    2016-09-30

    Craving is thought to play an important role in alcohol use disorders. The recent inclusion of "craving" as a formal diagnostic symptom calls for further investigation of this subjective phenomenon with multiple dimensions. Considering that alcohol-dependent patients compensate negative physical/emotional states with alcohol, the aim of this study is to investigate alcohol craving and its correlation with drinking measures and affective personality dimensions. A sample of 135 alcohol-dependent patients (104 males and 31 females) was collected from a clinical setting. Subjects self-rated their cravings (Penn Alcohol Craving Scale) and the stage of change. Several personality scales were also administered. Craving was related to drinking status, abstinence time, age, and taking steps. After controlling for these conditions, psychological characteristics related to low self-concept, neuroticism, cyclothymic affective temperament, depression, and hostility were found to be predictors of craving in sober alcohol-dependent patients. Our results support craving as a component of the phenomenology of alcohol dependence and highlight the presence of unpleasant feelings as predictors of craving in sober alcohol-dependent patients without co-occurring psychiatric conditions. The predisposition to experience negative emotions may induce a stronger craving response and increase the likelihood of a first drink and a subsequent loss of control.

  10. Cognitive and Affective Predictors of Rehabilitation Participation After Stroke

    PubMed Central

    Skidmore, Elizabeth R.; Whyte, Ellen M.; Holm, Margo B.; Becker, James T.; Butters, Meryl A.; Dew, Mary Amanda; Munin, Michael C.; Lenze, Eric J.

    2009-01-01

    Objective To examine associations between cognitive and affective impairments and rehabilitation participation during stroke rehabilitation. Design Secondary analyses of stroke patients who received acetylcholinesterase inhibitors during inpatient rehabilitation. Setting University-affiliated inpatient rehabilitation facilities. Patients Individuals admitted to inpatient stroke rehabilitation with impairment in attention, memory or executive functions (N=44). Interventions Secondary analysis of individuals receiving inpatient stroke rehabilitation care plus random assignment to one of two acetylcholinesterase inhibitors or no drug at rehabilitation admission. Main Outcome Measure(s) Correlations between measures of cognitive (Digit Span, Hopkins Verbal Learning Test, and Executive Interview) and affective impairments (Hamilton Rating Scale for Depression and Apathy Evaluation Scale) and participation (Pittsburgh Rehabilitation and Participation Scale) were examined. Significant correlates of participation were examined in a linear multiple regression model. Results Executive functions and depressive symptoms were significant correlates of participation. After controlling for baseline disability, executive functions predicted participation, but depressive symptoms did not, F4,32=9.35; R2=.54, P<.001. Conclusions These findings are an important first step toward understanding potentially modifiable clinical factors that contribute to rehabilitation participation, and overall functional status after rehabilitation. A better understanding of cognitive impairment and rehabilitation participation may be used to develop strategies for improving functional outcomes after stroke. PMID:20159122

  11. Online mutability of step direction during rapid stepping reactions evoked by postural perturbation.

    PubMed

    Tripp, Bryan P; McIlroy, William E; Maki, Brian E

    2004-03-01

    Stepping reactions are often triggered rapidly in response to loss of balance. It has been unclear whether spatial step parameters are defined at time of step-initiation or whether they can be modulated online, during step execution, in response to sensory feedback about the evolving state of instability. This study explored the capacity to actively alter step direction subsequent to step initiation in six healthy young-adult subjects. To elicit forward-step reactions, subjects were released suddenly from a tethered forward lean. A second perturbation (medio-lateral support-surface translation) was applied at lags of 0-200 ms. Active reaction to the second perturbation was determined primarily through analysis of swing-leg hip-abductor activation. In addition, to gauge the biomechanical consequence of the changes in muscle activation, we compared the measured medio-lateral swing-foot displacement to that predicted by a simple passive mechanical model. Perturbations at 0-100 ms lag evoked active medio-lateral swing-foot deviation, allowing balance to be recovered with a single step. However, when the second perturbation occurred near foot-off (200-ms lag), there was no evidence of active alteration of step direction and subjects typically required additional steps to recover balance. The results suggest that step direction can be reparameterized during early stages of stepping reactions, but that step direction was not actively modulated in response to perturbation arising near start of swing phase.

  12. Molecular mechanism of ERK dephosphorylation by striatal-enriched protein tyrosine phosphatase (STEP)

    PubMed Central

    Li, Hui; Li, Kang-shuai; Su, Jing; Chen, Lai-Zhong; Xu, Yun-Fei; Wang, Hong-Mei; Gong, Zheng; Cui, Guo-Ying; Yu, Xiao; Wang, Kai; Yao, Wei; Xin, Tao; Li, Min-Yong; Xiao, Kun-Hong; An, Xiao-fei; Huo, Yuqing; Xu, Zhi-gang; Sun, Jin-Peng; Pang, Qi

    2013-01-01

    Striatal-enriched tyrosine phosphatase (STEP) is an important regulator of neuronal synaptic plasticity, and its abnormal level or activity contributes to cognitive disorders. One crucial downstream effector and direct substrate of STEP is extracellular signal-regulated protein kinase (ERK), which has important functions in spine stabilisation and action potential transmission. The inhibition of STEP activity toward phospho-ERK has the potential to treat neuronal diseases, but the detailed mechanism underlying the dephosphorylation of phospho-ERK by STEP is not known. Therefore, we examined STEP activity toward pNPP, phospho-tyrosine-containing peptides, and the full-length phospho-ERK protein using STEP mutants with different structural features. STEP was found to be a highly efficient ERK tyrosine phosphatase that required both its N-terminal regulatory region and key residues in its active site. Specifically, both KIM and KIS of STEP were required for ERK interaction. In addition to the N-terminal KIS region, S245, hydrophobic residues L249/L251, and basic residues R242/R243 located in the KIM region were important in controlling STEP activity toward phospho-ERK. Further kinetic experiments revealed subtle structural differences between STEP and HePTP that affected the interactions of their KIMs with ERK. Moreover, STEP recognised specific positions of a phospho-ERK peptide sequence through its active site, and the contact of STEP F311 with phospho-ERK V205 and T207 were crucial interactions. Taken together, our results not only provide the information for interactions between ERK and STEP, but will also help in the development of specific strategies to target STEP-ERK recognition, which could serve as a potential therapy for neurological disorders. PMID:24117863

  13. [Special cases of multiple sclerosis].

    PubMed

    Mendibe Bilbao, Mar

    2014-12-01

    Multiple sclerosis is a chronic disease that usually occurs in young people and affects them for the rest of their lives. Patients and their families usually have a series of doubts and questions on everyday matters and all types of situations that occur during the distinct stages of life and which can influence the course of the disease. The aim of this review is to provide specific answers to these questions.

  14. Infant visual attention and step responsiveness to optic flow during treadmill stepping.

    PubMed

    Moerchen, Victoria A; Saeed, Mina E

    2012-12-01

    This study examined infant treadmill stepping in two groups of pre-locomotor infants in response to terrestrial optic flow. The optic flow was provided via the treadmill belt for flow translation that was directionally consistent with the forward stepping of the infants. Twelve 2-5-month-old and twelve 7-10-month-old infants participated. Visual attention (duration and direction) and step responsiveness (frequency and step types) were coded from digital video, and visuomotor coupling was examined by temporally juxtaposing the visual attention and step data. Longer durations of visual attention to the patterned belt with increased step frequencies during periods of visual attention were observed, suggesting that the visuotactile calibration afforded by the patterned treadmill belt, increased visuomotor coupling and enhanced the frequency and complexity of stepping in prelocomotor infants. The findings are discussed with regard to sensorimotor experiences that enhance treadmill stepping in infants and that may have application to clinical populations.

  15. Group Treatment for Mothers of Incest Victims: A Step by Step Approach.

    ERIC Educational Resources Information Center

    Landis, Lynn L.; Wyre, Charles H.

    1984-01-01

    Describes a step-by-step group treatment approach for mothers of incestuous families. The ten sessions provide support, help mothers identify protective plans for their children, and teach alternatives for handling significant relationships. (JAC)

  16. Local Climate Action Framework: A Step-by-Step Implementation Guide

    EPA Pesticide Factsheets

    This guide provides step-by-step guidance and resources for local governments to plan, implement, and evaluate climate, energy, and sustainability projects/programs to reduce greenhouse gas emissions and adapt to climate change impacts.

  17. Primes in Fibonacci n-step and Lucas n-step Sequences

    NASA Astrophysics Data System (ADS)

    Noe, Tony D.; Vos Post, Jonathan

    2005-09-01

    We search for primes in the Fibonacci n-step and Lucas n-step sequences, which are the natural generalizations of the Fibonacci and Lucas numbers. While the Fibonacci n-step sequences are nearly devoid of primes, the Lucas n-step sequences are prime-rich. We tabulate the occurrence of primes in the first 10000 terms for n <= 100. We also state two conjectures about Diophantine equations based on these sequences.

  18. Spinal focal lesion detection in multiple myeloma using multimodal image features

    NASA Astrophysics Data System (ADS)

    Fränzle, Andrea; Hillengass, Jens; Bendl, Rolf

    2015-03-01

    Multiple myeloma is a tumor disease in the bone marrow that affects the skeleton systemically, i.e. multiple lesions can occur in different sites in the skeleton. To quantify overall tumor mass for determining degree of disease and for analysis of therapy response, volumetry of all lesions is needed. Since the large amount of lesions in one patient impedes manual segmentation of all lesions, quantification of overall tumor volume is not possible until now. Therefore development of automatic lesion detection and segmentation methods is necessary. Since focal tumors in multiple myeloma show different characteristics in different modalities (changes in bone structure in CT images, hypointensity in T1 weighted MR images and hyperintensity in T2 weighted MR images), multimodal image analysis is necessary for the detection of focal tumors. In this paper a pattern recognition approach is presented that identifies focal lesions in lumbar vertebrae based on features from T1 and T2 weighted MR images. Image voxels within bone are classified using random forests based on plain intensities and intensity value derived features (maximum, minimum, mean, median) in a 5 x 5 neighborhood around a voxel from both T1 and T2 weighted MR images. A test data sample of lesions in 8 lumbar vertebrae from 4 multiple myeloma patients can be classified at an accuracy of 95% (using a leave-one-patient-out test). The approach provides a reasonable delineation of the example lesions. This is an important step towards automatic tumor volume quantification in multiple myeloma.

  19. 2-Step Maximum Likelihood Channel Estimation for Multicode DS-CDMA with Frequency-Domain Equalization

    NASA Astrophysics Data System (ADS)

    Kojima, Yohei; Takeda, Kazuaki; Adachi, Fumiyuki

    Frequency-domain equalization (FDE) based on the minimum mean square error (MMSE) criterion can provide better downlink bit error rate (BER) performance of direct sequence code division multiple access (DS-CDMA) than the conventional rake combining in a frequency-selective fading channel. FDE requires accurate channel estimation. In this paper, we propose a new 2-step maximum likelihood channel estimation (MLCE) for DS-CDMA with FDE in a very slow frequency-selective fading environment. The 1st step uses the conventional pilot-assisted MMSE-CE and the 2nd step carries out the MLCE using decision feedback from the 1st step. The BER performance improvement achieved by 2-step MLCE over pilot assisted MMSE-CE is confirmed by computer simulation.

  20. DEVELOPMENT OF A HYDROSTATIC JOURNAL BEARING WITH SLIT-STEP COMPENSATION

    SciTech Connect

    Hale, L C; Donaldson, R R; Castro, C; Chung, C A; Hopkins, D J

    2006-07-28

    This paper describes the mathematical modeling and initial testing of an oil-hydrostatic bearing that derives compensation from both a central radial slit where fluid enters and stepped clearances near each end. Bearings using either a radial slit or stepped clearances for compensation were well studied over forty years ago by Donaldson. These bearings have smooth bores uninterrupted with multiple recesses around the circumference. The present slit-step bearing achieves the best of both types with somewhat higher hydrostatic stiffness than the slit bearing and fluid shear drag lower than the step bearing. This is apparent in TABLE 1, which compares calculated values of initial (i.e., centered) hydrostatic stiffness for each type. The slit-step bearing is one of several types being studied at Lawrence Livermore National Laboratory for possible use on the Precision Optical Grinder and Lathe (POGAL).

  1. Fiber optic phase stepping system for interferometry

    NASA Technical Reports Server (NTRS)

    Mercer, Carolyn R.; Beheim, Glenn

    1991-01-01

    A closed loop phase control system using an all-fiber optical configuration has been developed for use in phase-stepping interferometry. This system drives the relative phase of two interfering beams through a sequence of pi/2 rad increments so that the initial relative phase of these beams can be determined. This phase-stepping system uses optical fibers to provide spatially uniform phase steps from a flexible, easily aligned optical configuration. In addition, this system uses phase feedback to eliminate phase modulator errors and to compensate for phase drifts caused by environmental disturbances.

  2. Phonon scattering in graphene over substrate steps

    SciTech Connect

    Sevinçli, H.; Brandbyge, M.

    2014-10-13

    We calculate the effect on phonon transport of substrate-induced bends in graphene. We consider bending induced by an abrupt kink in the substrate, and provide results for different step-heights and substrate interaction strengths. We find that individual substrate steps reduce thermal conductance in the range between 5% and 47%. We also consider the transmission across linear kinks formed by adsorption of atomic hydrogen at the bends and find that individual kinks suppress thermal conduction substantially, especially at high temperatures. Our analysis show that substrate irregularities can be detrimental for thermal conduction even for small step heights.

  3. Portfolio Planner: A Step-by-Step Guide to Portfolio Assessment.

    ERIC Educational Resources Information Center

    Jasmine, Julia

    This guide presents a step-by-step portfolio assessment method for teachers who want to implement portfolio assessment in their classrooms. Portfolio assessment is not neat or tidy in its early stages, but tidy and organized portfolios can be constructed if the outlined steps are followed. These are: (1) storage and establishing a file for each…

  4. Organizing Community-Wide Dialogue for Action and Change: A Step-by-Step Guide.

    ERIC Educational Resources Information Center

    Campbell, Sarah vL.; Malick, Amy; Landesman, John; Barrett, Molly Holme; Leighninger, Matt; McCoy, Martha L.; Scully, Patrick L.

    This document is a step-by-step guide to organizing a study circle program to serve as a vehicle to achieve communitywide dialogue for action and change. Part 1 provides an overview of communitywide study circle programs, with special emphasis on their operation and impact. Part 2 details the following steps in organizing a communitywide study…

  5. Effects of age and step length on joint kinetics during stepping task.

    PubMed

    Bieryla, Kathleen A; Buffinton, Christine

    2015-07-16

    Following a balance perturbation, a stepping response is commonly used to regain support, and the distance of the recovery step can vary. To date, no other studies have examined joint kinetics in young and old adults during increasing step distances, when participants are required to bring their rear foot forward. Therefore, the purpose of this study was to examine age-related differences in joint kinetics with increasing step distance. Twenty young and 20 old adults completed the study. Participants completed a step starting from double support, at an initial distance equal to the individual's average step length. The distance was increased by 10% body height until an unsuccessful attempt. A one-way, repeated measures ANOVA was used to determine the effects of age on joint kinetics during the maximum step distance. A two-way, repeated measures, mixed model ANOVA was used to determine the effects of age, step distance, and their interaction on joint kinetics during the first three step distances for all participants. Young adults completed a significantly longer step than old adults. During the maximum step, in general, kinetic measures were greater in the young than in the old. As step distance increased, all but one kinetic measure increased for both young and old adults. This study has shown the ability to discriminate between young and old adults, and could potentially be used in the future to distinguish between fallers and non-fallers.

  6. Recognition of Ramps and Steps by People with Low Vision

    PubMed Central

    Bochsler, Tiana M.; Legge, Gordon E.; Gage, Rachel; Kallie, Christopher S.

    2013-01-01

    Purpose. Detection and recognition of ramps and steps are important for the safe mobility of people with low vision. Our primary goal was to assess the impact of viewing conditions and environmental factors on the recognition of these targets by people with low vision. A secondary goal was to determine if results from our previous studies of normally sighted subjects, wearing acuity-reducing goggles, would generalize to low vision. Methods. Sixteen subjects with heterogeneous forms of low vision participated—acuities from approximately 20/200 to 20/2000. They viewed a sidewalk interrupted by one of five targets: a single step up or down, a ramp up or down, or a flat continuation of the sidewalk. Subjects reported which of the five targets was shown, and percent correct was computed. The effects of viewing distance, target–background contrast, lighting arrangement, and subject locomotion were investigated. Performance was compared with a group of normally sighted subjects who viewed the targets through acuity-reducing goggles. Results. Recognition performance was significantly better at shorter distances and after locomotion (compared with purely stationary viewing). The effects of lighting arrangement and target–background contrast were weaker than hypothesized. Visibility of the targets varied, with the step up being more visible than the step down. Conclusions. The empirical results provide insight into factors affecting the visibility of ramps and steps for people with low vision. The effects of distance, target type, and locomotion were qualitatively similar for low vision and normal vision with artificial acuity reduction. However, the effects of lighting arrangement and background contrast were only significant for subjects with normal vision. PMID:23221068

  7. Evaluation of Visual Arts Lesson Gains According to the Learning Steps of Cognitive, Affective Psychomotor Areas

    ERIC Educational Resources Information Center

    Tataroglu, Eylem

    2012-01-01

    Primary education (1-8 Grades) Visual Arts Instruction Schedule is a program built up and constituted by a commission composed of academicians and specialist teachers in their fields within the body of Ministry of National Education in year 2006 on the basis of "constructivist approach" philosophy of education. Instruction Schedule…

  8. Clinically used selective estrogen receptor modulators affect different steps of macrophage-specific reverse cholesterol transport.

    PubMed

    Fernández-Suárez, María E; Escolà-Gil, Joan C; Pastor, Oscar; Dávalos, Alberto; Blanco-Vaca, Francisco; Lasunción, Miguel A; Martínez-Botas, Javier; Gómez-Coronado, Diego

    2016-09-07

    Selective estrogen receptor modulators (SERMs) are widely prescribed drugs that alter cellular and whole-body cholesterol homeostasis. Here we evaluate the effect of SERMs on the macrophage-specific reverse cholesterol transport (M-RCT) pathway, which is mediated by HDL. Treatment of human and mouse macrophages with tamoxifen, raloxifene or toremifene induced the accumulation of cytoplasmic vesicles of acetyl-LDL-derived free cholesterol. The SERMs impaired cholesterol efflux to apolipoprotein A-I and HDL, and lowered ABCA1 and ABCG1 expression. These effects were not altered by the antiestrogen ICI 182,780 nor were they reproduced by 17β-estradiol. The treatment of mice with tamoxifen or raloxifene accelerated HDL-cholesteryl ester catabolism, thereby reducing HDL-cholesterol concentrations in serum. When [(3)H]cholesterol-loaded macrophages were injected into mice intraperitoneally, tamoxifen, but not raloxifene, decreased the [(3)H]cholesterol levels in serum, liver and feces. Both SERMs downregulated liver ABCG5 and ABCG8 protein expression, but tamoxifen reduced the capacity of HDL and plasma to promote macrophage cholesterol efflux to a greater extent than raloxifene. We conclude that SERMs interfere with intracellular cholesterol trafficking and efflux from macrophages. Tamoxifen, but not raloxifene, impair M-RCT in vivo. This effect is primarily attributable to the tamoxifen-mediated reduction of the capacity of HDL to promote cholesterol mobilization from macrophages.

  9. Clinically used selective estrogen receptor modulators affect different steps of macrophage-specific reverse cholesterol transport

    PubMed Central

    Fernández-Suárez, María E.; Escolà-Gil, Joan C.; Pastor, Oscar; Dávalos, Alberto; Blanco-Vaca, Francisco; Lasunción, Miguel A.; Martínez-Botas, Javier; Gómez-Coronado, Diego

    2016-01-01

    Selective estrogen receptor modulators (SERMs) are widely prescribed drugs that alter cellular and whole-body cholesterol homeostasis. Here we evaluate the effect of SERMs on the macrophage-specific reverse cholesterol transport (M-RCT) pathway, which is mediated by HDL. Treatment of human and mouse macrophages with tamoxifen, raloxifene or toremifene induced the accumulation of cytoplasmic vesicles of acetyl-LDL-derived free cholesterol. The SERMs impaired cholesterol efflux to apolipoprotein A-I and HDL, and lowered ABCA1 and ABCG1 expression. These effects were not altered by the antiestrogen ICI 182,780 nor were they reproduced by 17β-estradiol. The treatment of mice with tamoxifen or raloxifene accelerated HDL-cholesteryl ester catabolism, thereby reducing HDL-cholesterol concentrations in serum. When [3H]cholesterol-loaded macrophages were injected into mice intraperitoneally, tamoxifen, but not raloxifene, decreased the [3H]cholesterol levels in serum, liver and feces. Both SERMs downregulated liver ABCG5 and ABCG8 protein expression, but tamoxifen reduced the capacity of HDL and plasma to promote macrophage cholesterol efflux to a greater extent than raloxifene. We conclude that SERMs interfere with intracellular cholesterol trafficking and efflux from macrophages. Tamoxifen, but not raloxifene, impair M-RCT in vivo. This effect is primarily attributable to the tamoxifen-mediated reduction of the capacity of HDL to promote cholesterol mobilization from macrophages. PMID:27601313

  10. Cause-effect relationships concerning period-doubling bifurcations: step-by-step analysis of a complex system

    NASA Astrophysics Data System (ADS)

    Dejak, Camillo

    In this paper, the cause-effect relationships concerning the occurrence of the period-doubling bifurcation are analysed. Such analysis is carried out by investigating the dynamic of the simplest ODE systems. The governing equations of the system, in fact, contain only one non-linear term. Furthermore, the three state equations can be interpreted in ecological terms. The state equations were integrated using a purposely developed algorithm, based on a fourth order Taylor series expansion. This method allows one to follow the trajectories in a step-by-step detail and to compare the pre- and post-bifurcation ones. The results showed that the bifurcation is due to a very small change in the logarithmic derivative of the state variable which is directly affected by the non-linear term. This change cumulates over time and, in turn, affects the first two main variables, which can be taken as representative of the prey and predator density. The mechanism causes both, the detachment of the two limit cycles and their re-conjunction, after the next period. This finding is also interpreted in thermodynamic terms, by analysing the evolution of an entropy-like function. The above analysis showed that it is possible to detect early signs of bifurcation also for more complex systems and, in these cases, to identify the sub-set of state variables which is more affected by structural changes of the bifurcation dynamic of such systems.

  11. Audio-visual affective expression recognition

    NASA Astrophysics Data System (ADS)

    Huang, Thomas S.; Zeng, Zhihong

    2007-11-01

    Automatic affective expression recognition has attracted more and more attention of researchers from different disciplines, which will significantly contribute to a new paradigm for human computer interaction (affect-sensitive interfaces, socially intelligent environments) and advance the research in the affect-related fields including psychology, psychiatry, and education. Multimodal information integration is a process that enables human to assess affective states robustly and flexibly. In order to understand the richness and subtleness of human emotion behavior, the computer should be able to integrate information from multiple sensors. We introduce in this paper our efforts toward machine understanding of audio-visual affective behavior, based on both deliberate and spontaneous displays. Some promising methods are presented to integrate information from both audio and visual modalities. Our experiments show the advantage of audio-visual fusion in affective expression recognition over audio-only or visual-only approaches.

  12. Kinesics of Affective Instability.

    ERIC Educational Resources Information Center

    Dil, Nasim

    1979-01-01

    Discusses the rationale of studying kinesics of affective instability, describes the phenonmenon of affective instability, examines the role of kinesics in the overall process of communication, and presents three case studies. (Author/AM)

  13. Changing Your Habits: Steps to Better Health

    MedlinePlus

    ... Walking... A Step in the Right Direction Binge Eating Disorder Weight-loss & Nutrition Myths Helping Your Overweight Child ... Tips for Families (PDF, 1.47 MB) Binge Eating Disorder Celebrate the Beauty of Youth Changing Your Habits ...

  14. Four Practical Steps to Buying Copiers.

    ERIC Educational Resources Information Center

    Sturgeon, Julie

    1999-01-01

    Presents practical steps for avoiding overbuying when selecting copiers for university administration. Evaluating copying needs, eliminating excessive features, examining the dealer's capabilities, and being patient for the right price are discussed. (GR)

  15. Steps to Become a Green Power Community

    EPA Pesticide Factsheets

    Green Power Communities are a subset of the Green Power Partnership; municipalities or tribal governments where the local government, businesses, and residents collectively use enough green power to meet GPP requirements. Learn the steps to become a GPC.

  16. Planning Educational Volunteer Forums: Steps to Success.

    ERIC Educational Resources Information Center

    Culp, Ken III

    2000-01-01

    Five steps that can help ensure the success of workshops, conferences, or forums for extension volunteers: constructing the steering/planning committee; contracting facilities; planning the program; arranging for food, meals, and catering; and developing the budget. (SK)

  17. Optimal time step for incompressible SPH

    NASA Astrophysics Data System (ADS)

    Violeau, Damien; Leroy, Agnès

    2015-05-01

    A classical incompressible algorithm for Smoothed Particle Hydrodynamics (ISPH) is analyzed in terms of critical time step for numerical stability. For this purpose, a theoretical linear stability analysis is conducted for unbounded homogeneous flows, leading to an analytical formula for the maximum CFL (Courant-Friedrichs-Lewy) number as a function of the Fourier number. This gives the maximum time step as a function of the fluid viscosity, the flow velocity scale and the SPH discretization size (kernel standard deviation). Importantly, the maximum CFL number at large Reynolds number appears twice smaller than with the traditional Weakly Compressible (WCSPH) approach. As a consequence, the optimal time step for ISPH is only five times larger than with WCSPH. The theory agrees very well with numerical data for two usual kernels in a 2-D periodic flow. On the other hand, numerical experiments in a plane Poiseuille flow show that the theory overestimates the maximum allowed time step for small Reynolds numbers.

  18. Take Steps to Prevent Type 2 Diabetes

    MedlinePlus

    ... En español Take Steps to Prevent Type 2 Diabetes Browse Sections The Basics Overview Types of Diabetes ... 1 of 9 sections The Basics: Types of Diabetes What is diabetes? Diabetes is a disease. People ...

  19. Next Steps for Credit Availability Act

    THOMAS, 113th Congress

    Rep. Velazquez, Nydia M. [D-NY-12

    2013-01-03

    10/23/2013 Hearings Held by the Subcommittee on Capital Markets and Government Sponsored Enterprises Prior to Referral. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  20. Next Steps for Credit Availability Act

    THOMAS, 112th Congress

    Rep. Velazquez, Nydia M. [D-NY-12

    2012-06-08

    07/11/2012 Referred to the Subcommittee on Capital Markets and Government Sponsored Enterprises. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation: