Journal articles on the topic 'Variance counterbalance'
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Zhou, Jian, Guangxu Qin, Jianbing Zhang, Yancheng Li, Qiang He, Yi Han, and Benzhou Gong. "Study on the mutual interactions between the parameters of a CANON system and its coping strategy when operating at room temperature (15 to 25 °C) using response surface methodology." Water Science and Technology 69, no. 9 (February 7, 2014): 1805–12. http://dx.doi.org/10.2166/wst.2014.062.
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The coping strategy of a CANON (completely autotrophic nitrogen removal over nitrite) reactor working at room temperature was investigated using response surface methodology. The total nitrogen (TN) removal efficiency was taken as a dependent variable. The temperature (X), dissolved oxygen (DO) concentration (Y), and influent nitrogen loading rate (Z) were taken as independent variables. Results showed that the relation of these three independent variables can be described by the TN removal efficiency expressed as −5.03 + 1.51X + 45.16Y + 30.13Z + 0.26XY + 1.84XZ − 0.04X2 − 9.06Y2 − 99.00Z2. The analysis of variance proved that the equation is applicable. The response surface demonstrated that the temperature significantly interacts with the DO concentration and influent N loading rate. A coping strategy for the CANON reactor working at room temperature is thus proposed: altering the DO concentration and the N loading rate to counterbalance the impact of low temperature. The verification test proved the strategy is viable. The TN removal efficiency was 91.3% when the reactor was operated under a temperature of 35.0 °C, a DO of 3.0 mg/L, and a N loading rate of 0.70 kgN/(m³ d). When the temperature dropped from 35.0 to 19.2 °C, the TN removal efficiency was kept at 88.7% by regulating the influent N loading rate from 0.7 kgN/(m³ d) to 0.35 kgN/(m³ d) and the DO concentration from 3.0 to 2.6 mg/L.
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Sabarun, Sabarun. "The Effect Of Using ICT Based Graphic Organizer Across The Students’ Difference Level of Writing Ability." IJER (Indonesian Journal of Educational Research) 2, no. 2 (January 1, 2018): 77. http://dx.doi.org/10.30631/ijer.v2i2.43.
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The study is aimed at investigating whether ICT based graphic organizer gives facilitative effect or not across the students' difference level of writing ability. The study belongs to quasi experimental study by applying counterbalance procedure to collect the data. The participants are the 26 students of English department of Palangka Raya State Islamic Institute of 2017/ 2018 academic year. To test the hypotheses, a one way ANOVA test was applied. The research findings shows that, the data fulfills the normality using Shapiro Wilk test (p= 0.420, 0.046, 0.50, and 0.638> 0.05) and homogeneity of variance using Levene’s test (p= 0.541> 0.05). It is found that the F value is45.050, with the significance (p= 0.050> 0.000). Therefore, F table 4.040<45.050>3.190at the 5% and 1% of significant level (Df= 48). It meant that there is a very statistically significant difference on students’ writing achievement both for the bright and poor students between the students who writean expository essay using ICT Based graphic organizer and those who write an expository essay without using ICT Based graphic organizer
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Tong, Jiajin, Robert M. Bickmeier, and Steven G. Rogelberg. "A Comparison of Frequency- and Agreement-Based Response Formats in the Measurement of Burnout and Engagement." International Journal of Environmental Research and Public Health 17, no. 2 (January 15, 2020): 543. http://dx.doi.org/10.3390/ijerph17020543.
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The present research compares and contrasts frequency versus agreement response formats, two approaches to measuring job burnout and work engagement. Construct-based and measurement-based arguments for the superiority of the frequency response format in measuring burnout/engagement are provided, demonstrating that frequency-based measurements will explain relatively more variance in outcome variables. Fair comparison, time order counterbalance, and multiple measuring waves justify the comparison and reduce common method errors of self-report measures. Sample 1 (N = 242) was composed of employees from multiple organizations, while the participants in Sample 2 (N = 281) were employees from one company. Relative importance analysis showed that frequency outperforms the agreement response format in measuring burnout and engagement in both samples. These findings suggest that the frequency response format provides a more valuable method of detecting the dynamic nature of burnout/engagement, which offers methodological guidance for future research involving dynamic constructs. These findings can lead to improvements in the measurement of the dynamic experiences of burnout and engagement. This is one of the first studies to provide evidence whether the dynamic nature of the constructs would have any bearing on the response formats.
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Horn, David, Nir Levy, and Eytan Ruppin. "Memory Maintenance via Neuronal Regulation." Neural Computation 10, no. 1 (January 1, 1998): 1–18. http://dx.doi.org/10.1162/089976698300017863.
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Since their conception half a century ago, Hebbian cell assemblies have become a basic term in the neurosciences, and the idea that learning takes place through synaptic modifications has been accepted as a fundamental paradigm. As synapses undergo continuous metabolic turnover, adopting the stance that memories are engraved in the synaptic matrix raises a fundamental problem: How can memories be maintained for very long time periods? We present a novel solution to this long-standing question, based on biological evidence of neuronal regulation mechanisms that act to maintain neuronal activity. Our mechanism is developed within the framework of a neural model of associative memory. It is operative in conjunction with random activation of the memory system and is able to counterbalance degradation of synaptic weights and normalize the basins of attraction of all memories. Over long time periods, when the variance of the degradation process becomes important, the memory system stabilizes if its synapses are appropriately bounded. Thus, the remnant memory system is obtained by a dynamic process of synaptic selection and growth driven by neuronal regulatory mechanisms. Our model is a specific realization of dynamic stabilization of neural circuitry, which is often assumed to take place during sleep.
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Song, Jaeyoung, Sungbo Shim, Ji-Sun Kim, Jae-Hee Lee, Young-Hwa Byun, and Yeon-Hee Kim. "The Influence of Natural and Anthropogenic Forcing on Water and Energy Balance and on Photosynthesis." Land 10, no. 11 (October 29, 2021): 1151. http://dx.doi.org/10.3390/land10111151.
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Land surface processes are rarely studied in Detection and Attribution Model Inter-comparison Project (DAMIP) experiments on climate change. We analyzed a CMIP6 DAMIP historical experiment by using multi-linear regression (MLRM) and analysis of variance methods. We focused on energy and water budgets, including gross primary productivity (GPP). In MLRM, we estimated each forcing’s contribution and identified the role of natural forcing, which is usually ignored. Contributions of the forcing factors varied by region, and high-ranked variables such as net radiation could receive multiple influences. Greenhouse gases (GHG) accelerated energy and water cycles over the global land surface, including evapotranspiration, runoff, GPP, and water-use efficiency. Aerosol (AER) forcing displayed the opposite characteristics, and natural forcing accounted for short-term changes. A long-term analysis of total soil moisture and water budget indicated that as the AER increases, the available water on the global land increases continuously. In the recent past, an increase in net radiation (i.e., a lowered AER) reduced surface moisture and hastened surface water cycle (GHG effect). The results imply that aerosol emission and its counterbalance to GHG are essential to most land surface processes. The exception to this is GPP, which was overdominated by GHG effects.
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Pérez-Pérez, López-Férnandez, and Obeso. "Knowledge, Renewal and Flexibility: Exploratory Research in Family Firms." Administrative Sciences 9, no. 4 (November 11, 2019): 87. http://dx.doi.org/10.3390/admsci9040087.
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This study aims to explore how family firms pursue strategies that promote strategic flexibility and knowledge-management (KM) practices to respond to strategic-renewal goals. Specifically, based on a knowledge-based view of the firm, the following research question is proposed: Are there heterogeneous groups of family firms in terms of knowledge management, strategic flexibility and strategic renewal goals? To answer this question, an exploratory study using a two-step cluster analysis is developed. It reveals natural groupings from a sample of 288 small and medium-sized Spanish family enterprises (SMEs). The results obtained identified three distinctive clusters of family firms, namely proactive family firms, transitional or adaptive family firms, and rigid family firms. After two-step cluster analysis, we also conducted analysis of variance (ANOVA) to confirm that significant differences amongst the three clusters exist. After heterogeneity been confirmed, a further profile of the cluster solution was provided by using CEO and board characteristics, as well as the generational stage of the company. The findings offer some counterbalance for those studies that tend to study family businesses as a homogeneous entity, thus permitting researchers to access more information, providing rich explanations for renewal managerial decision-making purposes in family firm contexts.
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Price, Steven C., James E. Hill, and Robert W. Allard. "The Morphological and Physiological Response of Slender Oat (Avena barbata) to the Herbicides Barban and Difenzoquat." Weed Science 36, no. 1 (January 1988): 60–69. http://dx.doi.org/10.1017/s0043174500074464.
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The morphological and physiological response of the slender oat (Avena barbataPott ex Link # AVEBA) to the herbicides barban (4-chloro-2-butynyl 3-chlorophenylcarbamate) and difenzoquat (1,2-dimethyl-3,5-diphenyl-1H-pyrazolium) in conjunction with decreased water availability was determined for seven populations, representing three ecotypes, under greenhouse conditions. Generally, within the range of sublethal herbicide doses, with increasing herbicide rates, phytotoxicity ratings increased, but plant dry weight, tiller height, and number of spikelets were decreased. Also, the number of juvenile tillers decreased, while that of fertile tillers increased. Flag leaf area increased and flowering was delayed. The ratio of number of spikelets to plant dry weight and seed weight was influenced the least. Under the highest rates of difenzoquat, the within-plant variance of spikelet number decreased, indicating that there may have been a more equal partitioning of resources amongst tillers for spikelet production. The general influence of water stress was to amplify the effect of the herbicide. For example, the dry treatment reduced dry weight and tiller height, and delayed flowering. Within a particular herbicide treatment, the effect of the water stress was to cause reduced within-plant variance for days to flowering, flag leaf area, and number of spikelets. Three reactions were observed that could have helped buffer decreases in spikelet production: 1) An increased fraction of the dry weight of the plants was partitioned into the spikelets at the expense of other vegetative matter, 2) the increased leaf area of the primary tiller may have helped counterbalance any reduction in photosynthesis caused by herbicide action, and 3) an increased number of juvenile tillers was converted into fertile tillers resulting in an increased number of mature tillers. These data indicate that the slender oat has a remarkable “phenotypic plasticity,” which enables it to maintain reproductive structures under sublethal herbicide doses.
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Matheson, G. O., and D. C. McKenzie. "Breath holding during intense exercise: arterial blood gases, pH, and lactate." Journal of Applied Physiology 64, no. 5 (May 1, 1988): 1947–52. http://dx.doi.org/10.1152/jappl.1988.64.5.1947.
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Seven healthy endurance-trained [maximal O2 uptake (VO2max) = 57.1 +/- 4.1 ml.kg-1.min-1)] female volunteers (mean age 24.4 +/- 3.6 yr) served as subjects in an experiment measuring arterial blood gases, acid-base status, and lactate changes while breath holding (BH) during intense intermittent exercise. By the use of a counterbalance design, each subject repeated five intervals of a 15-s on:30-s off treadmill run at 125% VO2max while BH and while breathing freely (NBH). Arterial blood for pH, PO2, PCO2, O2 saturation (SO2) HCO3, and lactate was sampled from a radial arterial catheter at the end of each work and rest interval and throughout recovery, and the results were analyzed using repeated-measures analysis of variance. Significant reductions in pHa (delta mean = 0.07, P less than 0.01), arterial PO2 (delta mean = 24.2 Torr, P less than 0.01), and O2 saturation (delta mean = 4.6%, P less than 0.01) and elevations in arterial PCO2 (delta mean = 8.2 Torr, P less than 0.01) and arterial HCO3 (delta mean = 1.3 meq/l, P = 0.05) were found at the end of each exercise interval in the BH condition. All of the observed changes in arterial blood gases and acid-base status induced by BH were reversed during the rest intervals. During recovery, significantly (P less than 0.025) greater levels of arterial lactate were found in the BH condition.(ABSTRACT TRUNCATED AT 250 WORDS)
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Plasman, Matthieu, Christel Tiberi, Cecilia Cadio, Anita Thea Saraswati, Gwendoline Pajot-Métivier, and Michel Diament. "From space to lithosphere: inversion of the GOCE gravity gradients. Supply to the Earth’s interior study." Geophysical Journal International 223, no. 1 (June 26, 2020): 398–419. http://dx.doi.org/10.1093/gji/ggaa318.
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SUMMARY The emergence of high resolution satellite measurements of the gravitational field (GOCE mission) offers promising perspectives for the study of the Earth’s interior. These new data call for the development of innovant analysis and interpretation methods. Here we combine a forward prism computation with a Bayesian resolution approach to invert for these gravity gradient data configuration. We apply and test our new method on satellite data configuration, that is 225 km height with a global and homogeneous geographic distribution. We first quantify the resolution of our method according to both data and parametrization characteristics. It appears that for reasonable density contrast values (0.1 g cm−3) crustal structures have to be wider than ∼28 km to be detectable in the GOCE signal. Deeper bodies are distinguishable for greater size (35 km size at 50 km depth, ∼80 km at 300 km depth). We invert the six tensor components, among which five are independent. By carefully testing each of them and their different combinations, we enlighten a trade off between the recovery of data and the sensitivity to inversion parameters. We particularly discussed this characteristic in terms of geometry of the synthetic model tested (structures orientation, 3-D geometry, etc.). In terms of RMS value, each component is always better explained if inverted solely, but the result is strongly affected by the inversion parametrization (smoothing, variances, etc.). On the contrary, the simultaneous inversion of several components displays a significant improvement for the global tensor recovery, more dependent on data than on density variance or on smoothness control. Comparing gravity and gradient inversions, we highlight the superiority of the GG data to better reproduce the structures especially in terms of vertical location. We successfully test our method on a realistic case of a complex subduction case for both gradient and gravity data. While the imaging of small crustal structures requires terrestrial gravity data set, the longest wavelength of the slab is well recovered with both data sets. The precision and homogeneous coverage of GOCE data however, counterbalance the heterogeneous and often quite non-existence coverage of terrestrial gravity data. This is particularly true in large areas which requires a coherent assemblage of heterogeneous data sets, or in high relief, vegetally covered and offshore zones.
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Kim, Hwi-Su, Myeong-Su Bae, Chan-Hun Park, Doo-Hyung Kim, Jin-Ho Kyung, Hyun Min Do, Dong Il Park, Tae-Yong Choi, and Sung-Hyuk Song. "Design of Variable Counterbalance Mechanism Based on Spring to Minimize Required Torque of Robot Arm with Variable Payload." Journal of Institute of Control, Robotics and Systems 26, no. 12 (December 31, 2020): 1039–46. http://dx.doi.org/10.5302/j.icros.2020.20.0152.
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Park, Sung Hwan, Ji Min Lee, and Jong Shik Kim. "Modeling and Performance Improvement of the Constant Power Regulator Systems in Variable Displacement Axial Piston Pump." Scientific World Journal 2013 (2013): 1–11. http://dx.doi.org/10.1155/2013/738260.
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An irregular performance of a mechanical-type constant power regulator is considered. In order to find the cause of an irregular discharge flow at the cut-off pressure area, modeling and numerical simulations are performed to observe dynamic behavior of internal parts of the constant power regulator system for a swashplate-type axial piston pump. The commercial numerical simulation software AMESim is applied to model the mechanical-type regulator with hydraulic pump and simulate the performance of it. The validity of the simulation model of the constant power regulator system is verified by comparing simulation results with experiments. In order to find the cause of the irregular performance of the mechanical-type constant power regulator system, the behavior of main components such as the spool, sleeve, and counterbalance piston is investigated using computer simulation. The shape modification of the counterbalance piston is proposed to improve the undesirable performance of the mechanical-type constant power regulator. The performance improvement is verified by computer simulation using AMESim software.
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Hilz, Max J., Sankanika Roy, Carmen de Rojas Leal, Mao Liu, Francesca Canavese, Klemens Winder, Katharina M. Hoesl, De-Hyung Lee, Ralf A. Linker, and Ruihao Wang. "Cardiovascular fingolimod effects on rapid baroreceptor unloading are counterbalanced by baroreflex resetting." Neurological Sciences 42, no. 1 (January 2021): 111–21. http://dx.doi.org/10.1007/s10072-020-05004-1.
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Abstract Background and purpose Initial cardiovascular fingolimod effects might compromise baroreflex responses to rapid blood pressure (BP) changes during common Valsalva-like maneuvers. This study evaluated cardiovascular responses to Valsalva maneuver (VM)-induced baroreceptor unloading and loading upon fingolimod initiation. Patients and methods Twenty-one patients with relapsing-remitting multiple sclerosis performed VMs before and 0.5, 1, 2, 3, 4, 5, and 6 hours after fingolimod initiation. We recorded heart rate (HR) as RR intervals (RRI), systolic and diastolic BP (BPsys, BPdia) during VM phase 1, VM phase 2 early, VM phase 2 late, and VM phase 4. Using linear regression analysis between decreasing BPsys and RRI values during VM phase 2 early, we determined baroreflex gain (BRG) reflecting vagal withdrawal and sympathetic activation upon baroreceptor unloading. To assess cardiovagal activation upon baroreceptor loading, we calculated Valsalva ratios (VR) between maximal and minimal RRIs after strain release. Analysis of variance or Friedman tests with post hoc analysis compared corresponding parameters at the eight time points (significance: p < 0.05). Results RRIs at VM phase 1, VM phase 2 early, and VM phase 2 late were higher after than before fingolimod initiation, and maximal after 4 hours. Fingolimod did not affect the longest RRIs upon strain release, but after 3, 5, and 6 hours lowered the highest BPsys values during overshoot and all BPdia values, and thus reduced VRs. BRG was slightly higher after 3 and 5 hours, and significantly higher after 4 hours than before fingolimod initiation. Conclusions VR-decreases 3–6 hours after fingolimod initiation are physiologic results of fingolimod-associated attenuations of BP and HR increases at the end of strain and do not suggest impaired cardiovagal activation upon baroreceptor loading. Stable and at the time of HR nadir significantly increased BRGs indicate improved responses to baroreceptor unloading. Thus, cardiovascular fingolimod effects do not impair autonomic responses to sudden baroreceptor loading or unloading but seem to be mitigated by baroreflex resetting.
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Zhukova, Valentina, Paula Corte-Leon, Juan Maria Blanco, Mihail Ipatov, Alvaro Gonzalez, and Arcady Zhukov. "Development of Co-Rich Microwires with Graded Magnetic Anisotropy." Sensors 22, no. 1 (December 28, 2021): 187. http://dx.doi.org/10.3390/s22010187.
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In this paper, a gradual change in the hysteresis loop of Co-rich glass-coated microwire stress-annealed at variable temperature is observed. Such microwires annealed with a temperature gradient also present a variable squareness ratio and magnetic anisotropy field along the microwire’s length. The obtained graded anisotropy has been attributed to a gradual modification of the domain structure along the microwire originated by a counterbalance between shape, magnetoelastic, and induced magnetic anisotropies. Accordingly, we propose a rather simple route to design graded magnetic anisotropy in a magnetic microwire.
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Buyun, Wang, Liang Yi, Xu Dezhang, Zhang Yongde, and Xu Yong. "Design of a seed implantation robot with counterbalance and soft tissue stabilization mechanism for prostate cancer brachytherapy." International Journal of Advanced Robotic Systems 18, no. 5 (September 1, 2021): 172988142110406. http://dx.doi.org/10.1177/17298814211040687.
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This article focuses on the topic of the structural design of surgical radioactive surgery robot for prostate cancer. To improve the weight-to-payload ratio of surgery robot end-effector, the energy consumption and stability of robot joint drive and reducing the displacement and deformation of needle insertion in soft tissue. This article discusses the new static torque balancing method and multi-needle insertion soft tissue stabilization mechanisms that may be used in previously articulated seed implantation robots. Compared with the existing balancing system schemes, we adopt the idea of mutual conversion of gravitational potential energy and elastic potential energy and establish a static balancing model. With preloaded displacement parameter of the spring α, the variable gravity torque balance of robot arm can be achieved. Torque and equivalent gravity balancing distribution with the spring balance system and the quantitative evaluation experiment were performed, and experiment results provide evidence that these spring balance devices can basically compensate the gravity torque of the robot arm. In addition, we used nonlinear spring–damper model to establish multi-needles insertion soft tissue force model. Then, a variable multi-needle insertion soft tissue stabilization device is designed with six working modes. The innovative design of this device is the use of the first four needles that are introduced simultaneously on either side of the midline. Initially completed displacement simulation of different numbers of needle insertion prostate tissue, experiment results indicate that multi-needle puncture mechanism could reduce prostate displacement in the y- or z-direction. By this method, the prostate may be fixed, thus this mechanism maybe reduces rotation of the prostate and enabling subsequent needles to be inserted accurately.
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Du, Manuel, Richard Bernstein, Andreas Hoppe, and Kaspar Bienefeld. "Short-term effects of controlled mating and selection on the genetic variance of honeybee populations." Heredity 126, no. 5 (March 30, 2021): 733–47. http://dx.doi.org/10.1038/s41437-021-00411-2.
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AbstractDirectional selection in a population yields reduced genetic variance due to the Bulmer effect. While this effect has been thoroughly investigated in mammals, it is poorly studied in social insects with biological peculiarities such as haplo-diploidy or the collective expression of traits. In addition to the natural adaptation to climate change, parasites, and pesticides, honeybees increasingly experience artificial selection pressure through modern breeding programs. Besides selection, many honeybee breeding schemes introduce controlled mating. We investigated which individual effects selection and controlled mating have on genetic variance. We derived formulas to describe short-term changes of genetic variance in honeybee populations and conducted computer simulations to confirm them. Thereby, we found that the changes in genetic variance depend on whether the variance is measured between queens (inheritance criterion), worker groups (selection criterion), or both (performance criterion). All three criteria showed reduced genetic variance under selection. In the selection and performance criteria, our formulas and simulations showed an increased genetic variance through controlled mating. This newly described effect counterbalanced and occasionally outweighed the Bulmer effect. It could not be observed in the inheritance criterion. A good understanding of the different notions of genetic variance in honeybees, therefore, appears crucial to interpreting population parameters correctly.
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Nahanni, Celina C., Justin M. Deonarine, Martin Paré, and Kevin G. Munhall. "Sources of variance in the audiovisual perception of speech in noise." Seeing and Perceiving 25 (2012): 123. http://dx.doi.org/10.1163/187847612x647568.
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The sight of a talker’s face dramatically influences the perception of auditory speech. This effect is most commonly observed when subjects are presented audiovisual (AV) stimuli in the presence of acoustic noise. However, the magnitude of the gain in perception that vision adds varies considerably in published work. Here we report data from an ongoing study of individual differences in AV speech perception when English words are presented in an acoustically noisy background. A large set of monosyllablic nouns was presented at 7 signal-to-noise ratios (pink noise) in both AV and auditory-only (AO) presentation modes. The stimuli were divided into 14 blocks of 25 words and each block was equated for spoken frequency using the SUBTLEXus database (Brysbaert and New, 2009). The presentation of the stimulus blocks was counterbalanced across subjects for noise level and presentation. In agreement with Sumby and Pollack (1954), the accuracy of both AO and AV increase monotonically with signal strength with the greatest visual gain being when the auditory signal was weakest. These average results mask considerable variability due to subject (individual differences in auditory and visual perception), stimulus (lexical type, token articulation) and presentation (signal and noise attributes) factors. We will discuss how these sources of variance impede comparisons between studies.
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Smith, Cody D., Cameron A. Schmidt, Chien-Te Lin, Kelsey H. Fisher-Wellman, and P. Darrell Neufer. "Flux through mitochondrial redox circuits linked to nicotinamide nucleotide transhydrogenase generates counterbalance changes in energy expenditure." Journal of Biological Chemistry 295, no. 48 (August 3, 2020): 16207–16. http://dx.doi.org/10.1074/jbc.ra120.013899.
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Compensatory changes in energy expenditure occur in response to positive and negative energy balance, but the underlying mechanism remains unclear. Under low energy demand, the mitochondrial electron transport system is particularly sensitive to added energy supply (i.e. reductive stress), which exponentially increases the rate of H2O2 (JH2O2) production. H2O2 is reduced to H2O by electrons supplied by NADPH. NADP+ is reduced back to NADPH by activation of mitochondrial membrane potential–dependent nicotinamide nucleotide transhydrogenase (NNT). The coupling of reductive stress-induced JH2O2 production to NNT-linked redox buffering circuits provides a potential means of integrating energy balance with energy expenditure. To test this hypothesis, energy supply was manipulated by varying flux rate through β-oxidation in muscle mitochondria minus/plus pharmacological or genetic inhibition of redox buffering circuits. Here we show during both non-ADP– and low-ADP–stimulated respiration that accelerating flux through β-oxidation generates a corresponding increase in mitochondrial JH2O2 production, that the majority (∼70–80%) of H2O2 produced is reduced to H2O by electrons drawn from redox buffering circuits supplied by NADPH, and that the rate of electron flux through redox buffering circuits is directly linked to changes in oxygen consumption mediated by NNT. These findings provide evidence that redox reactions within β-oxidation and the electron transport system serve as a barometer of substrate flux relative to demand, continuously adjusting JH2O2 production and, in turn, the rate at which energy is expended via NNT-mediated proton conductance. This variable flux through redox circuits provides a potential compensatory mechanism for fine-tuning energy expenditure to energy balance in real time.
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Thompson, Anthony P., and Daniela D. Sota. "Comparison of WAIS—R and WISC—III Scores with a Sample of 16-Year-Old Youth." Psychological Reports 82, no. 3_suppl (June 1998): 1339–46. http://dx.doi.org/10.2466/pr0.1998.82.3c.1339.
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Scores on the Wechsler Adult Intelligence Scale-Revised (WAIS–R) and Wechsler Intelligence Scale for Children-Third Edition (WISC–III) were compared for 46 youth in the overlapping 16-yr.-age range Students were administered the tests in a counterbalanced order with an average retest interval of 40 days. Self-reported grade average was also obtained from students. Criteria for parallel tests (equal means, equal variances, equal covariances) were applied in the analyses. WAIS–R and WISC–III summary IQs were parallel, but corresponding subtest scores as a group were not parallel.
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Fuchs, Lynn S., and Linn Maxwell. "Interactive Effects of Reading Mode, Production Format, and Structural Importance of Text among LD Pupils." Learning Disability Quarterly 11, no. 2 (May 1988): 97–105. http://dx.doi.org/10.2307/1510987.
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This study assessed the effects of reading mode (oral vs. silent), production format (oral vs. written), and structural importance of text on the reading comprehension of LD pupils. Subjects were 44 LD students, randomly assigned to an oral or silent reading mode. Pupils were assessed twice, once using an oral recall and once a written recall, with production format order and passages counterbalanced. Analyses of variance conducted on percentage of idea units recalled at four levels of thematic importance indicated a three-way interaction. Differential performance between written and oral recall formats increased in linear fashion with more important thematic ideas for oral, but not silent, reading. Implications for reading instruction and research with LD pupils are discussed.
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Voglar, Matej, Anja Grandovec, and Rok Vatovec. "Effects of Foam Rolling on Strength and Flexibility of Hamstring Muscles." Sport Mont 20, no. 3 (October 1, 2022): 81–85. http://dx.doi.org/10.26773/smj.221013.
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Foam rolling is frequently implemented in warm-up prior to an exercise session. The purpose of this study was to evaluate the acute effects of a short bout of foam rolling on maximal knee flexion strength along with active and passive hamstring flexibility. Methods: Fourteen healthy young participants were included in this within-subject randomized controlled trial. After warm-up a short bout (two sets of 60 s) of foam rolling was performed on the intervention leg (counterbalanced leg dominance) while the contralateral leg was used as a control. Measurement of peak knee flexion torque and hamstring passive and active range of motion were performed on both sides in counterbalanced order. An analysis of variance was conducted to evaluate differences between the two groups. Results: Our results did not show significant differences between the intervention and control leg for any of the assessed parameters. Conclusion: The main findings are that a short bout of foam rolling does not affect maximal knee flexion strength and that the foam rolling intervention does not further affect flexibility although hamstring passive flexibility increases following a warm-up. Based on our results we conclude that short bouts of foam rolling can be used prior to exercise, as they have no deleterious effect on muscle performance. Foam rolling before exercise should be recommended solely based on individual preference.
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Ali, R. M., H. M. Abbas, and R. K. Kamal. "The effects of treatment with polyamines on dry matter, oil and flavonoid contents in salinity stressed chamomile and sweet marjoram." Plant, Soil and Environment 53, No. 12 (January 7, 2008): 529–43. http://dx.doi.org/10.17221/2188-pse.
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he study was undertaken to determine a possible role of polyamines (putrescine, spermidine, spermine) as antioxidants in salt tolerance of <I>Chamomilla recutita</I> and <I>Origanum majorana</I>. Salinity generally induced variable changes in growth, contents of oil and flavonoids of both plants; foliar application of any polyamines counterbalanced the effects of salinity. In general, the degree of stimulation differed according to the type and concentration of the used additive and the type of the plant.
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Schiraldi, Alberto. "Growth and Decay of a Planktonic Microbial Culture." International Journal of Microbiology 2020 (January 24, 2020): 1–8. http://dx.doi.org/10.1155/2020/4186468.
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The paper shows that the phenomenological trends of both growth and decay of a microbial population in a given medium are easily reproducible with simple equations that allow gathering the experimental data (plate counts) related to different microbial species, in different mediums and even at different temperatures, in a single master plot. The guideline of the proposed approach is that microbes and surrounding medium form a system where they affect each other and that the so-called “growth curve” is just the phenomenological appearance of such interaction. The whole system (cells and medium) changes following a definite pathway described as the evolution of a “virtual” microbial population in planktonic conditions. The proposed equations come from the assumption of a duplication mechanism with a variable generation time for the growth and of an exponential-like decline with a linear increase of the rate for the decay. The intermediate phase between growth and decay is a time span during which growth and death counterbalance each other and age differences within the virtual cell population tend to level off. The proposed approach does not provide an a priori description of this phase but allows the fit of the whole evolution trend of a microbial culture whenever the experimental data are available. Deviations of such a trend concern microbes able to form spores, modify their metabolism, or express phenotypic heterogeneity, to counterbalance adverse medium conditions.
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Qiu, Donghai, Manuel Paredes, and Sébastien Seguy. "Variable pitch spring for nonlinear energy sink: Application to passive vibration control." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 2 (March 1, 2018): 611–22. http://dx.doi.org/10.1177/0954406218761485.
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This paper aims to propose a generalized methodology for designing a novel nonlinear energy sink with variable pitch springs. To this end, a generic model of the nonlinear energy sink system providing the nonlinearity of pure cubic stiffness is introduced. Key features of the model include: (i) specifically sizing two variable pitch springs to provide the force polynomial components with only linear and cubic terms; (ii) pre-compressing two springs at the transition point to produce smooth nonlinear force characteristics; (iii) adding a negative stiffness mechanism to counterbalance the linear term. To generate the variable pitch spring, design parametrization is implemented. The type of shape and the pitch distribution adopted for the spring are shown to fit the objective force–displacement function well. To validate the concept, a special sized nonlinear energy sink system is developed. Identification of the force–displacement relation and experiments for the whole system embedded on an electrodynamic shaker are studied. The results show that this nonlinear energy sink can not only output the anticipated nonlinearity, but can also produce energy pumping to protect the primary system in a large band of frequencies, thus making it practical for the application of passive vibration control.
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Scruggs, Thomas E. "Psychology of Computer Use: VI. Effectiveness of Computer-Assisted Instruction in Expository Writing." Perceptual and Motor Skills 67, no. 3 (December 1988): 871–77. http://dx.doi.org/10.2466/pms.1988.67.3.871.
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31 high school students were given writing assignments on a computer-writing program (WANDAH) or on a free writing control condition in a crossover design in which order of condition and writing topics were counterbalanced. Results indicated that students in the WANDAH condition wrote significantly more words, longer sentences, and showed significantly longer on-task behavior. However, the proportion of “be” (inactive) words per sentence and number of sentences written were apparently not affected by the WANDAH program. Significant differences in variances were also observed between conditions on number of words written per T-unit. Survey data indicated that students favored writing with this computer program over writing by hand.
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Carolina Gomes, Ana, Laura Tosini, Dalton Oliveira, Guilherme Lage, Emerson Franchini, and Cassio Meira Jr. "Caffeine Produces Neutral Effects on Extraverts’ and Introverts’ Performance of Fundamental Motor Skills." Journal of Human Kinetics 78, no. 1 (March 1, 2021): 229–37. http://dx.doi.org/10.2478/hukin-2021-0038.
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Abstract Extraverts are active and talkative, while introverts are quiet and calm. This difference has been attributed to the cortical activation level (arousal), which is low in extraverts and high in introverts. Thus, to reach an optimal level of arousal, extraverts seek stimulation and introverts avoid it. As caffeine increases arousal levels, our primary aim was to investigate the effect of caffeine on the performance of extraverted and introverted university students in the execution of stability, manipulative, and locomotor tasks. Considering the above, we evaluated side effects, such as restlessness and trembling of hands, we also analyzed the individual's perception regarding caffeine intake and the placebo. Forty two volunteers were classified as 21 extraverts and 21 introverts by the Eysenck Personality Questionnaire. Participants performed three tasks on two different days, having previously ingested caffeine and a placebo in counterbalanced order. A double-blind technique was employed. The dependent variable was the execution time to perform the tasks. The analyses of variance [2 (extraversion/introversion) x 2 (caffeine x placebo)] for each task did not show significant differences. Regarding the secondary aim, the chi-square test showed that introverts had a better perception of the substance they had ingested than did extraverts. Our findings indicate that in the execution of stability, manipulative, and locomotor tasks, either caffeine or the placebo produced the same effect, regardless of the participants' extraversion score. In addition, introverts were more sensitive to perceive which substance was ingested, caffeine or the placebo, than extraverts.
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Yuan, Rui, Yu Sun, Wen Hai Fan, Kai Wu, and Zheng Jun Chen. "Research on Balancing Method for Inertia Force of Slider-Crank Mechanism with Small Linkage Ratio." Advanced Materials Research 591-593 (November 2012): 2011–15. http://dx.doi.org/10.4028/www.scientific.net/amr.591-593.2011.
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In view of the difficult balance of inertia force for the slider-crank mechanism, on the basis of analyzing inertia force of the slider-crank mechanism, a new balancing method of inertia force was proposed for the slider-crank mechanism with small linkage ratio, the rotary mass and the moving mass had replaced the mechanism mass, the inertia force of rotary mass was balanced by rotary weight counterbalance, a spring was disposed by slider, it provided variable elastic force and balanced the inertia force of moving mass. Then the balancing method was analyzed deeply and the theoretical derivation was made, the results show that this balancing method would achieved approximately balance for inertia force of the slider-crank mechanism with small linkage ratio.
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Ng, Cheuk Fan, and Jeffrey Turnbull. "Preference for Noise and Effectiveness of Studying." Perceptual and Motor Skills 85, no. 1 (August 1997): 155–60. http://dx.doi.org/10.2466/pms.1997.85.1.155.
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The hypothesis that studying was equally effective in an environment with a preferred versus a nonpreferred amount of noise was tested. University students' preference for noise ( N = 112) was measured with ratings on Weinstein's Noise Sensitivity Scale and responses to seven questions about study habits. A month later, 20 students who reported a preference for noise and 20 students with a preference for quiet studied in a room in which there was noise (recorded cafeteria noise, 75 dB) and in quiet (50–55 dB) on two separate days. Within each preference for noise condition, the order of exposure to noise and to quiet was counterbalanced. An analysis of variance of accuracy scores on tests of reading comprehension indicated no significant difference between conditions. The interaction effect between preference for noise and conditions of noise was also not significant.
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Rui, Guo, Lei Liu, Sheng Zhen-Xin, and Song Pu. "A three-dimensional bistatic reverberation model of underwater explosion by interface scattering at variable sound speeds." Journal of Low Frequency Noise, Vibration and Active Control 38, no. 2 (December 12, 2018): 427–40. http://dx.doi.org/10.1177/1461348418816458.
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Underwater reverberation is a main limitation of the sonar performance and thereby the reverberation level estimation becomes crucial. In this study, based on the Lambert law and ray theory, a model for predicting 3D bistatic reverberation performance by interface scattering at linear sound speed profile is established and then verified through the underwater explosion experiments. The Influences of source and receiver positions, and relative sound speed gradient on reverberation performance are further investigated. The results indicate that: (1) the proposed model can predict the short-range mean reverberation level effectively, with the deviation 2–4 dB and describe the whole reverberation level distribution in some details; (2) at the early reverberation phase, the interference effects between the interface scattering sounds are considerable and a dominating interface exists; the counterbalance between the losses by scattering, spreading and medium absorption results in the local high-intensity zones close to corresponding interfaces, respectively; (3) as the sound source moves towards some interface, associated local high-intensity zone gradually expands, while the other one shrinks; if the sound speed approaches are constant, an extra local high-intensity zone will appear between the previous two but with a lower magnitude.
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Rivaz, Hassan, and Robert Rohling. "An Active Dynamic Vibration Absorber for a Hand-Held Vibro-Elastography Probe." Journal of Vibration and Acoustics 129, no. 1 (September 21, 2006): 101–12. http://dx.doi.org/10.1115/1.2424982.
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Vibro-elastography is a new medical imaging method that identifies the mechanical properties of tissue by measuring tissue motion in response to a multi-frequency external vibration source. Previous research on vibro-elastography used ultrasound to measure the tissue motion and system identification techniques to identify the tissue properties. This paper describes a hand-held probe with a combined vibration source and ultrasound transducer to implement the new method as a practical device. The device uses a proportional integral active dynamic vibration absorber with an electromagnetic actuator to counterbalance the reaction forces from contact with the tissue. Experiments show an operational frequency range of 5-20Hz, with at least 15dB vibration absorption in 0.4s for single frequency excitation. Experiments with variable frequency and amplitude excitation also show a high level of vibration absorption.
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Chrisler, Joan C., Ingrid K. Johnston, Nicole M. Champagne, and Kathleen E. Preston. "Menstrual Joy." Psychology of Women Quarterly 18, no. 3 (September 1994): 375–87. http://dx.doi.org/10.1111/j.1471-6402.1994.tb00461.x.
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Fifty female college students participated in a study of women's health. In a counterbalanced design, half of the participants completed the Menstrual Joy Questionnaire (MJQ) and the Menstrual Attitude Questionnaire (MAQ) in the first testing session. A week later they completed the Menstrual Distress Questionnaire (MDQ) and the Menstrual Attitude Questionnaire. The other participants completed the MDQ and MAQ in the first session and the MJQ and MAQ in the second. A multivariate analysis of variance revealed that those who received the MJQ first reported more positive cyclic changes on the MDQ and more positive attitudes on the MAQ. A follow-up study of 40 college students examined their responses to the MJQ. Participants reported that they were surprised or incredulous; most had not previously considered positive aspects of the menstrual cycle. Thirty percent reported that the MJQ had caused them to look at menstruation in a different way.
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Beckett, Christine Alyn. "Directing Student Attention during Two-Part Dictation." Journal of Research in Music Education 45, no. 4 (December 1997): 613–25. http://dx.doi.org/10.2307/3345426.
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This study is an exploration of undergraduate music majors' strategies in two-part dictation. Sixty volunteers received three dictation sessions—two that directed attention to rhythm first or pitch first, and one that was nondirected. The dependent measure, written dictation accuracy, was analyzed by means of separate pitch and rhythm scores. For six counterbalanced groups (n = 10), analysis of variance showed no order effects. A repeated measures MANOVA (accuracy by condition) showed a significant effect for condition (p < .0001). Higher rhythm accuracy occurred in the rhythm-first condition when it was compared to the nondirected (p < .05) and pitch-first (p < .0001) conditions. Pitch accuracy was not affected by condition. Accuracy was unrelated to covariates examined (years of theory and counterpoint study, keyboard skill, and private strategy). Results suggest that in polyphonic dictation, attending to rhythm first and pitch afterwards may be an effective way of maximizing rhythmic accuracy.
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Verovšek, Peter J. "Memory, narrative, and rupture: The power of the past as a resource for political change." Memory Studies 13, no. 2 (August 17, 2017): 208–22. http://dx.doi.org/10.1177/1750698017720256.
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In politics, “soft” ideational factors are often dismissed in favor of “hard” quantifiable data. Since the “memory boom,” however, collective memory has become an important variable for explaining persistent grievances and cycles of hatred. Building on the work of Hannah Arendt and the first generation of the Frankfurt School, I seek to counterbalance the literature’s predominantly negative conception of memory by developing a constructive understanding of remembrance as a resource for rethinking politics in the aftermath of breaks in the narrative thread of historical time. My basic thesis is that historical ruptures shared by an entire generation can activate collective memory as a resource for reimagining political life. I show how Arendt and the critical theorists of the early Frankfurt School used the caesura of 1945 to rethink the meaning of the past and endorse new forms of political life in the aftermath of Europe’s age of total war.
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Ren, Jinlong, Yingchao Liu, Xingqiang Shi, Guangcun Shan, Mingming Tang, Chaocheng Kaun, and Kunpeng Dou. "Flexoelectricity Driven Fano Resonance in Slotted Carbon Nanotubes for Decoupled Multifunctional Sensing." Research 2021 (December 29, 2021): 1–9. http://dx.doi.org/10.34133/2021/9821905.
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Multifunctionality, interference-free signal readout, and quantum effect are important considerations for flexible sensors equipped within a single unit towards further miniaturization. To address these criteria, we present the slotted carbon nanotube (CNT) junction features tunable Fano resonance driven by flexoelectricity, which could serve as an ideal multimodal sensory receptor. Based on extensive ab initio calculations, we find that the effective Fano factor can be used as a temperature-insensitive extrinsic variable for sensing the bending strain, and the Seebeck coefficient can be used as a strain-insensitive intrinsic variable for detecting temperature. Thus, this dual-parameter permits simultaneous sensing of temperature and strain without signal interference. We further demonstrate the applicability of this slotted junction to ultrasensitive chemical sensing which enables precise determination of donor-type, acceptor-type, and inert molecules. This is due to the enhancement or counterbalance between flexoelectric and chemical gating. Flexoelectric gating would preserve the electron–hole symmetry of the slotted junction whereas chemical gating would break it. As a proof-of-concept demonstration, the slotted CNT junction provides an excellent quantum platform for the development of multistimuli sensation in artificial intelligence at the molecular scale.
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Yoon, Yang-Soo, Callie Michelle Boren, and Brianna Diaz. "Effect of Realistic Test Conditions on Spectral and Temporal Processing in Normal-Hearing Listeners." American Journal of Audiology 30, no. 1 (March 10, 2021): 160–69. http://dx.doi.org/10.1044/2020_aja-20-00120.
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Purpose To measure the effect of testing conditions (in the soundproof booth vs. quiet room), test order, and number of test sessions on spectral and temporal processing in normal-hearing (NH) listeners. Method Thirty-two adult NH listeners participated in the three experiments. For all three experiments, the stimuli were presented to the left ear at the subjects' most comfortable level through headphones. All tests were administered in an adaptive three-alternative forced-choice paradigm. Experiment 1 was designed to compare the effect of soundproof booth and quiet room test conditions on amplitude modulation detection threshold and modulation frequency discrimination threshold with each of the five modulation frequencies. Experiment 2 was designed to compare the effect of two test orders on the frequency discrimination thresholds under the quiet room test conditions. The thresholds were first measured in the ascending and descending order of four pure tones, and then with counterbalanced order. For Experiment 3, the amplitude discrimination threshold under the quiet room testing condition was assessed 3 times to determine the effect of the number of test sessions. Then the thresholds were compared over the sessions. Results Results showed no significant effect of test environment. The test order is an important variable for frequency discrimination, particularly between piano tunes and pure tones. Results also show no significant difference across test sessions. Conclusions These results suggest that a controlled test environment may not be required in spectral and temporal assessment for NH listeners. Under the quiet test environment, a single outcome measure is sufficient, but test orders should be counterbalanced.
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Rao, R. H. "Fasting glucose homeostasis in the adaptation to chronic nutritional deprivation in rats." American Journal of Physiology-Endocrinology and Metabolism 268, no. 5 (May 1, 1995): E873—E879. http://dx.doi.org/10.1152/ajpendo.1995.268.5.e873.
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The hormonal basis for the metabolic paradox of relative hypoglycemia despite insulinopenia and insulin resistance in chronic nutritional deprivation was studied in weanling rats restricted to 60% of ad libitum intake over 8 wk (n = 12 each). Lower insulin and glucagon levels were observed in both peripheral and portal blood (P = 0.0016) in the malnourished rats on multivariate analysis of variance, indicating decreased islet secretion. Peripheral and portal hormone levels were proportionately similar, indicating that hepatic extraction was not altered. Despite relative hypoglycemia, glucose turnover rate, total glucose mass, and volume of distribution of glucose were not altered. This indicates that the sum total of the effects of malnutrition on the various hormonal influences controlling glucose turnover had resulted in the establishment of a new dynamic equilibrium associated with lower plasma glucose levels. It is concluded that fasting glucose levels are sustained at a lower level in chronic malnutrition by an adaptive process that includes insulin resistance and insulinopenia, counterbalanced not only by glucagon resistance, as shown earlier, but also by decreased glucagon secretion.
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Lyman, Katie J., Michael McCrone, Thomas A. Hanson, Christopher D. Mellinger, and Kara Gange. "Kinesio® Tape Barrier Does Not Inhibit Intramuscular Cooling During Cryotherapy." Journal of Sport Rehabilitation 28, no. 7 (September 1, 2019): 671–76. http://dx.doi.org/10.1123/jsr.2018-0009.
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Context: Allied health care professionals commonly apply cryotherapy as treatment for acute musculoskeletal trauma and the associated symptoms. Understanding the impact of a tape barrier on intramuscular temperature can assist in determining treatment duration for effective cryotherapy. Objective: To determine whether Kinesio® Tape acts as a barrier that affects intramuscular temperature during cryotherapy application. Design: A repeated-measures, counterbalanced design in which the independent variable was tape application and the dependent variable was muscle temperature as measured by thermocouples placed 1 cm beneath the adipose layer. Additional covariates for robustness were body mass index and adipose thickness. Setting: University research laboratory. Participants: Nineteen male college students with no contraindications to cryotherapy, no known sensitivity to Kinesio® Tape, and no reported quadriceps injury within the past 6 months. Intervention: Topical cryotherapy: cubed ice bags of 1 kg and 0.5 kg. Main Outcome Measures: Intramuscular temperature. Results: The tape barrier had no statistically significant effect on muscle temperature. The pattern of temperature change was indistinguishable between participants with and without tape application. Conclusions: Findings suggest that health care professionals can combine cryotherapy with a Kinesio® Tape application without any need for adjustments to cryotherapy duration.
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Ugrinowitsch, Herbert, Cíntia De Oliveira Matos, Thiago Fernandes Neves, Guilherme Menezes Lage, Patrick Costa Ribeiro-Silva, and Madson Pereira Cruz. "Constant and random practice on learning of volleyball serve." Brazilian Journal of Kinanthropometry and Human Performance 20, no. 6 (February 19, 2019): 598–606. http://dx.doi.org/10.5007/1980-0037.2018v20n6p598.
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The type of practice can influence what is learned from a motor skill. The aim of this study was to investigate the effects of the constant and random practice on the learning of Generalized Motor Program and parameters of the volleyball serve. The sample was composed of 20 children between 10 and 12 years old. The participants performed a pre-test whose score was adopted to counterbalance two groups (n=10), random practice and constant practice. During the acquisition phase, the random group performed 252 serves from three different positions, always indicated at the end of each serve, and the constant group performed all serves from only a specific position. The retention test showed that both groups learned the Generalized Motor Program, but random practice conducted to higher parameterization learning, resultant from the variable of practice. During practice of a sport motor skills, although the constant and random practice improve the learning of Generalized Motor Program, only the random practice improves learning of parameters of the motor skill.
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Mengren, Jin, and Wang Qingfeng. "Efficient pump and meter-out control for electrohydraulic system with time-varying negative load." Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 232, no. 9 (May 28, 2018): 1170–81. http://dx.doi.org/10.1177/0959651818776868.
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In hydraulic systems under negative loads, counterbalance valves are widely employed, which introduce instability and sizable energy consumption. This article focuses on the electrohydraulic system with meter-out orifice and variable pump, which allows flexible control structure. The target is to reduce inlet pressure level as well as diminish oscillation caused by time-varying loads. An extended load observer is constructed to estimate the external load. Accordingly, a robust back-stepping controller with integral part and disturbance compensation is proposed to regulate the meter-out orifice, achieving velocity-oriented control. Also, a model-based pressure-oriented controller is developed to determine pump displacement. The target is set to 3 bar in this work, while the pressure losses in conventional systems are more than 12 bar. The stabilities of these two independent controllers are both proved by Lyapunov theory. Experiments focusing on energy consumption, load compensation, and velocity tracking are carried out verifying the controller effectiveness. Discussions of results illustrate that the whole proposed controller succeeds in velocity tracking and reducing energy consumption in the presence of time-varying negative load.
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Friman, Patrick C., Keith M. McPherson, William J. Warzak, and Joseph Evans. "Influence of Thumb Sucking on Peer Social Acceptance in First-Grade Children." Pediatrics 91, no. 4 (April 1, 1993): 784–86. http://dx.doi.org/10.1542/peds.91.4.784.
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Chronic thumb sucking in school-age children may reduce peer social acceptance, an important contributor to social development. The influence of thumb sucking on social acceptance was assessed among 40 first-grade children, who were shown four slides of two 7-year-old children (one boy, one girl) in two poses (one thumb sucking, one not). After viewing each slide in their classrooms, the children answered 10 numerically weighted questions related to peer acceptance. To limit the possibility that the children would determine the girl and boy were the same in each pose, the slide presentation was counterbalanced across two sessions 1 week apart. Using a repeated-measures analysis of variance, the authors compared composite scores on each question for both poses. The results indicate that while in the thumb-sucking pose, the children were rated as significantly less intelligent, happy, attractive, likable, and fun and less desirable as a friend, playmate, seatmate, classmate, and neighbor than when they were in the non-thumb-sucking pose. These findings suggest that the risk of reduced social acceptance should be added to the list of potentially harmful effects of chronic thumb sucking in school-age children.
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Gammage, Kimberley L., Breanne Drouin, and Larkin Lamarche. "Comparing a Yoga Class with a Resistance Exercise Class: Effects on Body Satisfaction and Social Physique Anxiety in University Women." Journal of Physical Activity and Health 13, no. 11 (November 2016): 1202–9. http://dx.doi.org/10.1123/jpah.2015-0642.
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Purpose:The current study compared a single yoga group exercise class and a resistance group exercise class for their effects on state body satisfaction and social physique anxiety in women.Methods:A pretest-posttest design was used. Participants (N = 46) completed both a resistance exercise class and yoga class in a counterbalanced order. Measures of body satisfaction and social physique anxiety were completed immediately before and after each class.Results:A 2 (time) × 2 (class type) repeatedmeasures multiple analysis of variance showed a significant overall Time × Class Type interaction (F2,44 = 5.69, P < .01, η p2 = .21). There was a significant increase in body satisfaction after the yoga class. After both classes, there was a significant decrease in social physique anxiety, but the magnitude of the change was larger after the yoga class than after the resistance class.Conclusions:Both types of exercise class were associated with improvements in body image, but there were greater improvements after the yoga class. This study provided evidence of the positive effects of yoga for reducing state social physique anxiety and increasing state body satisfaction, adding to correlational evidence suggesting that yoga is particularly beneficial for improving body image-related outcomes in women.
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Smith, Kimberly A., Michael Gallagher, Anne E. Hays, Fredric L. Goss, and Robert Robertson. "Development of the Physical Activity Index as a Measure of Total Activity Load and Total Kilocalorie Expenditure During Submaximal Walking." Journal of Physical Activity and Health 9, no. 6 (August 2012): 757–64. http://dx.doi.org/10.1123/jpah.9.6.757.
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Background:Pedometers are most accurate at measuring steps, less accurate at estimating distance, and even less accurate at estimating kilocalorie expenditure. The purpose of this investigation was to create a Physical Activity Index (PAI) using pedometer step counts and rating of perceived exertion (RPE) to enhance the ability to estimate kilocalorie expenditure during walking exercise.Methods:Thirty-two females performed 3 counterbalanced walking bouts. During each bout, oxygen consumption, RPE, and step counts were measured. The PAI was calculated as the product of RPE and step count for each of the bouts.Results:Concurrent validation of the PAI was established using VO2 as the criterion variable. A multiple regression analysis revealed a strong, positive relation between PAI score and VO2 (r = .91). Data were then used to develop a statistical model to estimate kcal expenditure using the PAI score as the predictor variable.Conclusion:The PAI was found to be an accurate method of estimating kcal expenditure and is a simple, unobtrusive and inexpensive tool which may be used in public health settings.
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Deere, Kerry A., Gregory F. Grether, Aida Sun, and Janet S. Sinsheimer. "Female mate preference explains countergradient variation in the sexual coloration of guppies ( Poecilia reticulata )." Proceedings of the Royal Society B: Biological Sciences 279, no. 1734 (November 23, 2011): 1684–90. http://dx.doi.org/10.1098/rspb.2011.2132.
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We tested the hypothesis that mate choice is responsible for countergradient variation in the sexual coloration of Trinidadian guppies ( Poecilia reticulata ). The nature of the countergradient pattern is that geographical variation in the carotenoid content of the orange spots of males is counterbalanced by genetic variation in drosopterin production, resulting in a relatively uniform pigment ratio. A female hue preference could produce this pattern, because hue is the axis of colour variation most directly affected by the pigment ratio. To test this hypothesis, we crossed two populations differing in drosopterin production and produced an F 2 generation with variable drosopterin levels. When the carotenoid content of the orange spots was held constant, female guppies preferred males with intermediate drosopterin levels. This shows that females do not simply prefer males with greater orange spot pigment content; instead, the ratio of the pigments also affects male attractiveness. To our knowledge, this is the first direct evidence for a hypothesized agent of countergradient sexual selection.
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Newell, Tim, Janet Simon, and Carrie L. Docherty. "Arch-Taping Techniques for Altering Navicular Height and Plantar Pressures During Activity." Journal of Athletic Training 50, no. 8 (August 1, 2015): 825–32. http://dx.doi.org/10.4085/1062-6050-50.5.05.
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Context Arch tapings have been used to support the arch by increasing navicular height. Few researchers have studied navicular height and plantar pressures after physical activity. Objective To determine if taping techniques effectively support the arch during exercise. Design Crossover study. Setting Athletic training research laboratory. Patients or Other Participants Twenty-five individuals (13 men, 12 women; age = 20.0 ± 1.0 years, height = 172.3 ± 6.6 cm, mass = 70.1 ± 10.2 kg) with a navicular drop of more than 8 mm (12.9 ± 3.3 mm) volunteered. Intervention(s) All individuals participated in 3 days of testing, with 1 day for each tape condition: no tape, low dye, and navicular sling. On each testing day, navicular height and plantar pressures were measured at 5 intervals: baseline; posttape; and after 5, 10, and 15 minutes of running. The order of tape condition was counterbalanced. Main Outcome Measure(s) The dependent variables were navicular height in millimeters and plantar pressures in kilopascals. Plantar pressures were divided into 5 regions: medial forefoot, lateral forefoot, lateral midfoot, lateral rearfoot, and medial rearfoot. Separate repeated-measures analyses of variance were conducted for each dependent variable. Results Navicular height was higher immediately after application of the navicular-sling condition (P = .004) but was reduced after 5 minutes of treadmill running (P = .12). We observed no differences from baseline to posttape for navicular height for the low-dye (P = .30) and no-tape conditions (P = .25). Both the low-dye and navicular-sling conditions increased plantar pressures in the lateral midfoot region compared with the no-tape condition. The low-dye condition created decreased pressure in the medial and lateral forefoot regions compared with the no-tape condition. All changes were identified immediately after application and were maintained during running. No changes were noted in plantar pressures for the no-tape condition (P > .05). Conclusions Both taping techniques effectively changed plantar pressures in the lateral midfoot, and these changes were sustained throughout the 15 minutes of exercise.
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Albergel, C., J. C. Calvet, J. F. Mahfouf, C. Rüdiger, A. L. Barbu, S. Lafont, J. L. Roujean, J. P. Walker, M. Crapeau, and J. P. Wigneron. "Monitoring of water and carbon fluxes using a land data assimilation system: a case study for southwestern France." Hydrology and Earth System Sciences Discussions 7, no. 2 (March 3, 2010): 1705–44. http://dx.doi.org/10.5194/hessd-7-1705-2010.
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Abstract. A Land Data Assimilation System (LDAS) able to ingest surface soil moisture (SSM) and Leaf Area Index (LAI) observations is tested at local scale to increase prediction accuracy for water and carbon fluxes. The ISBA-A-gs Land Surface Model (LSM) is used together with LAI and the soil water content observations of a grassland at the SMOSREX experimental site in southwestern France for a seven-year period (2001–2007). Three configurations corresponding to contrasted model errors are considered: (1) best case (BC) simulation with locally observed atmospheric variables and model parameters, and locally observed SSM and LAI used in the assimilation, (2) same as (1) but with the precipitation forcing set to zero, (3) real case (RC) simulation with atmospheric variables and model parameters derived from regional atmospheric analyses and from climatological soil and vegetation properties, respectively. In configuration (3) two SSM time series are considered: the observed SSM using Thetaprobes, and SSM derived from the LEWIS L-band radiometer located 15 m above the ground. Performance of the LDAS is examined in the three configurations described above with either one variable (either SSM or LAI) or two variables (both SSM and LAI) assimilated. The joint assimilation of SSM and LAI has a positive impact on the carbon, water, and heat fluxes. It represents a greater impact than assimilating one variable (either LAI or SSM). Moreover, the LDAS is able to counterbalance large errors in the precipitation forcing given as input to the model.
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Albergel, C., J. C. Calvet, J. F. Mahfouf, C. Rüdiger, A. L. Barbu, S. Lafont, J. L. Roujean, J. P. Walker, M. Crapeau, and J. P. Wigneron. "Monitoring of water and carbon fluxes using a land data assimilation system: a case study for southwestern France." Hydrology and Earth System Sciences 14, no. 6 (June 29, 2010): 1109–24. http://dx.doi.org/10.5194/hess-14-1109-2010.
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Abstract. A Land Data Assimilation System (LDAS) able to ingest surface soil moisture (SSM) and Leaf Area Index (LAI) observations is tested at local scale to increase prediction accuracy for water and carbon fluxes. The ISBA-A-gs Land Surface Model (LSM) is used together with LAI and the soil water content observations of a grassland at the SMOSREX experimental site in southwestern France for a seven-year period (2001–2007). Three configurations corresponding to contrasted model errors are considered: (1) best case (BC) simulation with locally observed atmospheric variables and model parameters, and locally observed SSM and LAI used in the assimilation, (2) same as (1) but with the precipitation forcing set to zero, (3) real case (RC) simulation with atmospheric variables and model parameters derived from regional atmospheric analyses and from climatological soil and vegetation properties, respectively. In configuration (3) two SSM time series are considered: the observed SSM using Thetaprobes, and SSM derived from the LEWIS L-band radiometer located 15m above the ground. Performance of the LDAS is examined in the three configurations described above with either one variable (either SSM or LAI) or two variables (both SSM and LAI) assimilated. The joint assimilation of SSM and LAI has a positive impact on the carbon, water, and heat fluxes. It represents a greater impact than assimilating one variable (either LAI or SSM). Moreover, the LDAS is able to counterbalance large errors in the precipitation forcing given as input to the model.
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Zhang, Beikun, and Liyun Xu. "An improved flower pollination algorithm for solving a Type-II U-shaped assembly line balancing problem with energy consideration." Assembly Automation 40, no. 6 (September 18, 2020): 847–56. http://dx.doi.org/10.1108/aa-07-2019-0144.
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Purpose The increasing energy shortage leads to worldwide attentions. This paper aims to develop a mathematical model and optimization algorithm to solve the energy-oriented U-shaped assembly line balancing problem. Different from most existing works, the energy consumption is set as a major objective. Design/methodology/approach An improved flower pollination algorithm (IFPA) is designed to solve the problem. The random key encoding mechanism is used to map the continuous algorithm into discrete problem. The pollination rules are modified to enhance the information exchange between individuals. Variable neighborhood search (VNS) is used to improve the algorithm performance. Findings The experimental results show that the two objectives are in conflict with each other. The proposed methodology can help manager obtain the counterbalance between them, for the larger size balancing problems, and the reduction in objectives is even more significant. Besides, the experiment results also show the high efficiency of the proposed IFPA and VNS. Originality/value The main contributions of this work are twofold. First, a mathematical model for the U-shaped assembly line balancing problem is developed and the model is dual foci including minimized SI and energy consumption. Second, an IFPA is proposed to solve the problem.
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Watson, Kevin, Israel Halperin, Joan Aguilera-Castells, and Antonio Dello Iacono. "A comparison between predetermined and self-selected approaches in resistance training: effects on power performance and psychological outcomes among elite youth athletes." PeerJ 8 (November 12, 2020): e10361. http://dx.doi.org/10.7717/peerj.10361.
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Background The aim of this study was to investigate if choice over resistance training exercise order affects motor performance and psychological outcomes among elite youth hockey players. Methods Seventeen elite hockey players (male, n = 14; female, n = 3, age: 15.1 ± 1.1 years) participated in this study. In the first session, individual optimum power loads were calculated in the back squat, jump squat, bench press and bench throw exercises. Then, in four counterbalanced sessions, participants completed three sets of six repetitions in the same exercises loaded with their optimum power loads. In two sessions, athletes used a self-selected order of exercises, while in other two sessions the order was predetermined. Power outputs were estimated with a linear position transducer. Fatigue and enjoyment were measured during and after the sessions using standardized questionnaires. Repeated measures analyses of variance and a paired-sample t-test were used to compare the effects between conditions. Results We observed trivial to small differences between conditions in power outputs (p ≥ 0.07; ES ≤ 0.21), fatigue (p ≥ 0.42; ES ≤ 0.33) and enjoyment (p = 0.72; ES = 0.05). Conclusion Given the comparable effects between approaches, both can be used when coaching youth athletes. Self-selecting the order of exercises based on preferences is a feasible and practical coaching option when working with youth athletes.
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Amini, Amin, and Mohammad Vaezmousavi. "The Effect of Differential Attentional Focus Strategies on the Performance of Military Elite Shooters." Behavioural Neurology 2020 (November 25, 2020): 1–8. http://dx.doi.org/10.1155/2020/1067610.
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Background and Objective. The effect of attentional focus strategies on performance has been an interesting area of investigation, especially when the precision of performance is of significance. The purpose of the present study is to investigate the effect of different attentional focus strategies on performance precision of elite military shooters. Methods. This study is semiexperimental with an intragroup design. A number of 10 military marksmen (30-42 years old) with at least 10 years of experience in shooting performed under four attentional focus strategies in a counterbalanced design. In each strategy, two blocks (each consisting of 20 trials) were conducted. Shooters’ performance was recorded using SCATT device and analyzed using the factorial variance analysis with repeated measure. Results. Results showed that the interactional effects of internal-external/relevant-irrelevant focuses of attention were significant on shooting record, shooting accumulation, and stability on the target center. Results suggest that the external-relevant attentional focus strategies were more effective than other focus strategies. Conclusion. The results of the study support the hypothesis that external-relevant attentional focus produced better scores, better accumulation, more stability at the target center, and less average fluctuation. Therefore, this attentional focus strategy improves performance precision of military elite shooters.
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Rose, Paige. "Effects of movement, tempo, and gender on steady beat performance of kindergarten children." International Journal of Music Education 34, no. 1 (May 14, 2014): 104–15. http://dx.doi.org/10.1177/0255761414533309.
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The purposes of this research were to discover the effects of manual (hand) and pedal (foot) movements, tempo, and gender on steady beat accuracy. Participants ( N = 119) consisted of male ( n = 63) and female ( n = 56) kindergarten students randomly divided into two groups, counterbalanced with regard to school, homeroom, and gender. Participants performed steady beat by either tapping or stepping on MIDI controllers. Given a visual model, students were asked to synchronize to the steady beat of musical examples at slow (80 bpm), medium (100 bpm), and fast (120 bpm) tempi. Participants had lowest overall accuracy scores at the fast tempo and highest accuracy scores at the medium tempo. Lowest scores for both males and females were found with pedal movement at a fast tempo. Females performed best with manual movement at a slow tempo, while males performed best with manual movement at a medium tempo. Overall, participants in the manual group scored higher than participants in the pedal group at all tempi. Results of the two-way mixed analysis of variance revealed no main effect for tempi or gender and no statistically significant interactions. There was a main effect for manual/pedal grouping, with manual participants scoring higher than pedal participants.
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Kogan, Yefim. "LES study of microphysical variability bias in shallow cumulus." Advances in Science and Research 14 (May 2, 2017): 103–7. http://dx.doi.org/10.5194/asr-14-103-2017.
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Abstract. Subgrid-scale (SGS) variability of cloud microphysical variables over the mesoscale numerical weather prediction (NWP) model has been evaluated by means of joint probability distribution functions (JPDFs). The latter were obtained using dynamically balanced Large Eddy Simulation (LES) model dataset from a case of marine trade cumulus initialized with soundings from Rain in Cumulus Over the Ocean (RICO) field project. Bias in autoconversion and accretion rates from different formulations of the JPDFs was analyzed. Approximating the 2-D PDF using a generic (fixed-in-time), but variable-in-height JPDFs give an acceptable level of accuracy, whereas neglecting the SGS variability altogether results in a substantial underestimate of the grid-mean total conversion rate and producing negative bias in rain water. Nevertheless the total effect on rain formation may be uncertain in the long run due to the fact that the negative bias in rain water may be counterbalanced by the positive bias in cloud water. Consequently, the overall effect of SGS neglect needs to be investigated in direct simulations with a NWP model.