Meaningful Fit Research Articles

Genetic variation in male-induced harm in Drosophila melanogaster.

In Drosophila melanogaster, prolonged exposure to males reduces the longevity and fecundity of females. This harm arises from the effects of male courtship behaviours and the toxic side effects of the accessory gland proteins (Acps) in their seminal fluids. Here, we examine the relationship between male exposure and its harmful effect on the lifetime fitness of his mates, and quantify the genetic basis for this variation. We found significant additive genetic variation in the magnitude of harm that males impose on females by exposing females to males from a variety of hemiclonal backgrounds for either a brief or prolonged period of time and measuring their fecundity, a meaningful fitness index. Furthermore, we discovered a strong negative correlation between the magnitude of harm and the short-term effects of male exposure on female fitness. We discuss the evolutionary significance of these results with regards to potential life-history trade-offs in females, and its relationship to male body size.

A Latent Profile Analysis of drinking motives among heavy drinking college students

IntroductionPositively (Enhancement and Social) and negatively (Coping) reinforcing drinking motives have been shown to be associated with alcohol use, alcohol-related problems, and depression among college students. Although prior studies of drinking motives have mostly consisted of variable-centered analyses, the current study used a person-centered approach where individuals were grouped into categories based on shared characteristics using Latent Profile Analysis (LPA). We investigated the utility of drinking motive profiles to determine how different profiles were associated with alcohol outcomes and depressive symptoms. MethodParticipants were 648 undergraduate students who had violated a university alcohol policy and who endorsed consuming alcohol in the past month. Social, Coping, and Enhancement subscales from the Drinking Motives Questionnaire were used as indicators. ResultsAfter examining one-through-eight class LPA solutions, the six-class solution provided the best empirical and clinically meaningful fit to the data. Classes with high coping and high positive reinforcing drinking motives consumed more alcohol than profiles of students with high coping and low positive reinforcing motives. Classes high on both coping and positively reinforcing motives reported the most alcohol related problems. Classes with higher levels of coping motives and either high or low positive reinforcing motives reported the highest depression symptoms. ConclusionsDrinking motive profiles differ in terms of alcohol outcomes and depressive symptoms. We encourage researchers to explore motives for drinking with individuals, especially assessing the relationship between coping motives and depression in the presence or absence of positively reinforcing motives.

Health-related physical fitness assessment in a community-based cancer rehabilitation setting.

Assessment of physical fitness is important in order to set goals, appropriately prescribe exercise, and monitor change over time. This study aimed to determine the utility of a standardized physical fitness assessment for use in cancer-specific, community-based exercise programs. Tests anticipated to be feasible and suitable for a community setting and a wide range of ages and physical function were chosen to measure body composition, aerobic fitness, strength, flexibility, and balance. Cancer Exercise Trainers/Specialists at cancer-specific, community-based exercise programs assessed new clients (n = 60) at enrollment, designed individualized exercise programs, and then performed a re-assessment 3-6 months later (n = 34). Resting heart rate, blood pressure, body mass index, waist circumference, handgrip strength, chair stands, sit-and-reach, back scratch, single-leg standing, and timed up-and-go tests were considered suitable and feasible tests/measures, as they were performed in most (≥88 %) participants. The ability to capture change was also noted for resting blood pressure (-7/-5 mmHg, p = 0.02), chair stands (+4, p < 0.01), handgrip strength (+2 kg, p < 0.01), and sit-and-reach (+3 cm, p = 0.03). While the submaximal treadmill test captured a meaningful improvement in aerobic fitness (+62 s, p = 0.17), it was not completed in 33 % of participants. Change in mobility, using the timed up-and-go was nominal and was not performed in 27 %. Submaximal treadmill testing, handgrip dynamometry, chair stands, and sit-and-reach tests were feasible, suitable, and provided meaningful physical fitness information in a cancer-specific, community-based, exercise program setting. However, a shorter treadmill protocol and more sensitive balance and upper body flexibility tests should be investigated.

Physical mechanism responsible for degradation of organic light-emitting diodes

Degradation of organic light-emitting diodes (OLEDs) is primarily due to the formation of the non-emissive centers, and their formation rate is dependent on the temperature. We observed the linear dependence of total luminance on the temperature, and formulated a novel degradation model to present an analytic function for the OLED degradation with physically meaningful fitting parameters. It was found that the stretched exponential decay (SED) behavior of the degradation is mainly due to the temperature dependence of the luminance.

MODELING THE FLYBY ANOMALIES WITH DARK MATTER SCATTERING: UPDATE WITH ADDITIONAL DATA AND FURTHER PREDICTIONS

We continue our exploration of whether the flyby anomalies can be explained by scattering of spacecraft nucleons from dark matter gravitationally bound to the Earth, with the addition of data from five new flybys to that from the original six. We continue to use our model in which inelastic and elastic scatterers populate shells generated by the precession of circular orbits with normals tilted with respect to the Earth's axis. With 11 data points and eight parameters in the model, a statistically meaningful fit is obtained with a chi-squared of 2.7. We give plots of the anomalous acceleration along the spacecraft trajectory, and the cumulative velocity change, for the five flybys which exhibit a significant nonzero anomaly. We also discuss implications of the fit for dark matter–nucleon cross-sections, give the prediction of our fit for the anomaly to be expected from the future Juno flyby, and give predictions of our fit for flyby orbit orientation changes. In addition, we give formulas for estimating the flyby temperature increase caused by dark matter inelastic scattering, and for the fraction of flyby nucleons undergoing such scatters. Finally, for circular satellite orbits, we give a table of predicted secular changes in orbit radius. These are much too large to be reasonable — comparing with data for COBE and GP-B supplied to us by Edward Wright (after the first version of this paper was posted), we find that our model predicts changes in orbit radius that are too large by many orders of magnitude. So the model studied here is ruled out. We conclude that further modeling of the flyby anomalies must simultaneously attempt to fit constraints coming from satellite orbits.

Long-term evolution is surprisingly predictable in lattice proteins

It has long been debated whether natural selection acts primarily upon individual organisms, or whether it also commonly acts upon higher-level entities such as lineages. Two arguments against the effectiveness of long-term selection on lineages have been (i) that long-term evolutionary outcomes will not be sufficiently predictable to support a meaningful long-term fitness and (ii) that short-term selection on organisms will almost always overpower long-term selection. Here, we use a computational model of protein folding and binding called 'lattice proteins'. We quantify the long-term evolutionary success of lineages with two metrics called the k-fitness and k-survivability. We show that long-term outcomes are surprisingly predictable in this model: only a small fraction of the possible outcomes are ever realized in multiple replicates. Furthermore, the long-term fitness of a lineage depends only partly on its short-term fitness; other factors are also important, including the 'evolvability' of a lineage-its capacity to produce adaptive variation. In a system with a distinct short-term and long-term fitness, evolution need not be 'short-sighted': lineages may be selected for their long-term properties, sometimes in opposition to short-term selection. Similar evolutionary basins of attraction have been observed in vivo, suggesting that natural biological lineages will also have a predictive long-term fitness.

TCAD simulation of SOI TFETs and calibration of non-local band-to-band tunneling model

This paper reports a simulation based study of the non-local tunneling model using a commercially available technology computer-aided design (TCAD) device simulator. Single gate Tunnel FET devices with 400nm gate length based on SOI technology are measured and compared with simulated data. A step by step algorithm to calibrate the nonlocal band-to-band tunneling model implemented in Synopsys Sentaurus TCAD has been shown, demonstrating the importance of model parameters. By using only the reduced mass as the fitting parameter we have obtained a physically meaningful fit with the measured data. The dependence of the tunneling generation rate on the different crystallographic directions is also demonstrated for the first time.

Musically meaningful fitness and mutation for autonomous evolution of rhythm accompaniment

Autonomous evaluation of computer generated musical pieces remains one of the most challenging open problems in evolutionary music composition. This paper introduces the design of novel mutation and fitness operators for autonomous evolution of human-competitive rhythm accompaniment using genetic algorithm. We propose several fitness operators that autonomously evaluate the quality of generated rhythm phrases according to patterns of another accompanying instrument, such as bass or rhythm piano, and according to user's specified criteria such as a density of rhythm accompaniment. In the next, we introduce four musically meaningful mutation operators that alter rhythm consonance, dynamic phrasing, drum stroke types or perform syncopation of rhythm phrases. We also provide a complete example of mutation and fitness settings used for evolution of a rhythm accompaniment to Dizzy Gillespie's "Night In Tunisia" jazz tune.

A COMBINED SUBARU/VLT/MMT 1-5 μm STUDY OF PLANETS ORBITING HR 8799: IMPLICATIONS FOR ATMOSPHERIC PROPERTIES, MASSES, AND FORMATION

We present new 1--1.25 micron (z and J band) Subaru/IRCS and 2 micron (K band) VLT/NaCo data for HR 8799 and a rereduction of the 3--5 micron MMT/Clio data first presented by Hinz et al. (2010). Our VLT/NaCo data yields a detection of a fourth planet at a projected separation of ~ 15 AU -- "HR 8799e". We also report new, albeit weak detections of HR 8799b at 1.03 microns and 3.3 microns. Empirical comparisons to field brown dwarfs show that at least HR 8799b and HR8799c, and possibly HR 8799d, have near-to-mid IR colors/magnitudes significantly discrepant from the L/T dwarf sequence. Standard cloud deck atmosphere models appropriate for brown dwarfs provide only (marginally) statistically meaningful fits to HR 8799b and c for unphysically small radii. Models with thicker cloud layers not present in brown dwarfs reproduce the planets' SEDs far more accurately and without the need for rescaling the planets' radii. Our preliminary modeling suggests that HR 8799b has log(g) = 4--4.5, Teff = 900K, while HR 8799c, d, and (by inference) e have log(g) = 4--4.5, Teff = 1000--1200K. Combining results from planet evolution models and new dynamical stability limits implies that the masses of HR 8799b, c, d, and e are 6--7 Mj, 7--10 Mj, 7--10 Mj and 7--10 Mj. 'Patchy" cloud prescriptions may provide even better fits to the data and may lower the estimated surface gravities and masses. Finally, contrary to some recent claims, forming the HR 8799 planets by core accretion is still plausible, although such systems are likely rare.

Does flax have the answer to the GM mix-up?

Does flax have the answer to the GM mix-up?

Increasing the Utility of the Copper Cylinder Expansion Test

We report the development of a new methodology for analyzing CYLEX tests streak images. In these tests, the displacement of the wall of an explosive filled cylinder is obtained by backlighting the cylinder. The profile is imaged through a slit and streaked across a film record as the cylinder is detonated. A critical step in processing this data is the spatial calibration of the film and extraction of the profile of the cylinder from the image. Historically this has been a tedious task as it was performed by eye with the assistance of an optical comparator. Recently we developed an algorithm which automates the data calibration and extraction process of digitized streak records utilizing the Shen-Castan edge detection algorithm and the image processing capabilities found in the IGOR PRO software. The new processing methodology greatly increases the resolution of the data, removes human subjectivity, and reduces analysis time from hours to seconds. The higher resolution of the new method has enabled much greater accuracy in measuring early-time (<15 µs) expansion. With the aid of CTH hydrocode calculations, new fitting functions were developed to model both the early and late-time expansion data. These functions contain physically meaningful fitting parameters and include terms which mimic the intensity and time scales of the shock and gas induced expansion of the cylinder independently. We demonstrate the methodology and hydrocode calculations on a recent CYLEX test series aimed at examining the effects of a plastic liner on high-purity oxygen-free copper cylinders filled with a high explosive.

Social Culture – Paving the Way Towards Service to Humanity

True education is meant for creating prosperous and humane society. This requires development of integrated and balanced personality. In most of the educational ventures, one important aspect remains ignored i.e., the development of child’s character suffused with the values and social etiquettes. Education is not merely a process of providing information, knowledge and skills to a person but also socializing him to establish meaningful fit with one’s family, society and the creation. Besides, one should be able to study his inner reality. Education should socialize the child to understand his connection with the society and develop his capacities to reap mutually beneficial and meaningful outcomes. This will result into growth of social skills, responsibility & initiative, adjustment & respect, co-operation, co-ordination, patience, self-confidence and perseverance. Through varied and innovative techniques, the child should be helped to enrich his personality.

Selecting pseudo-absence data for presence-only distribution modeling: How far should you stray from what you know?

An important decision in presence-only species distribution modeling is how to select background (or pseudo-absence) localities for model parameterization. The selection of such localities may influence model parameterization and thus, can influence the appropriateness and accuracy of the model prediction when extrapolating the species distribution across time and space. We used 12 species from the Australian Wet Tropics (AWT) to evaluate the relationship between the geographic extent from which pseudo-absences are taken and model performance, and shape and importance of predictor variables using the MAXENT modeling method. Model performance is lower when pseudo-absence points are taken from either a restricted or broad region with respect to species occurrence data than from an intermediate region. Furthermore, variable importance (i.e., contribution to the model) changed such that, models became increasingly simplified, dominated by just two variables, as the area from which pseudo-absence points were drawn increased. Our results suggest that it is important to consider the spatial extent from which pseudo-absence data are taken. We suggest species distribution modeling exercises should begin with exploratory analyses evaluating what extent might provide both the most accurate results and biologically meaningful fit between species occurrence and predictor variables. This is especially important when modeling across space or time—a growing application for species distributional modeling.

Compact model of output conductance in nanoscale bulk MOSFET based on 2D analytical calculations

In this paper we present a new way to calculate channel length shortening in saturation for standard bulk MOSFETs by solving 2D Poisson’s equation. Compared to most existing models, we use in our model only physically meaningful and geometry-independent fitting parameters, which gives our model a good scalability. 2D Poisson is solved in analytical closed form by applying the conformal mapping technique. This gives the model the advantage additionally to its application in circuit simulations to be useful in calculating device scaling behavior. Our model describes the output conductance of MOSFETs down to 50nm effective channel length very well.

A user-friendly water retention function that takes account of the textural and structural pore spaces in soil

A double-exponential water retention equation with 5 adjustable parameters is introduced in order to fill the need for a user-friendly equation in which all the terms have a distinct physical meaning. It is compared with the van Genuchten [van Genuchten, M.Th., 1980. A closed-form equation for predicting the hydraulic conductivity of unsaturated soils. Soil Sci. Soc. Am. J. 44, 892–898] equation in its 3-, 4- and 5-parameter forms. The double-exponential equation provided good fits to water retention data obtained by immiscible-displacement experiments on samples collected from 42 Polish soil horizons. The double-exponential equation gives positive values for the residual water contents of the soils as expected after immiscible displacement. It is proposed that the two exponential terms relate to the matrix and structural pore spaces in the soil. It is explained how the measures of matrix and structural pore space obtained here relate to porosity measurements made on soil samples of different sizes by French soil scientists. With the use of water retention measurements made on large numbers of soil samples collected from two experimental fields in Poland, the double-exponential water retention equation is used to show how soil bulk density increases at the expense of structural porosity, whereas the matrix porosity is not significantly affected. For each soil, there is a critical bulk density at which the structural porosity is zero. At this critical bulk density, mechanical and transport properties of soil may be expected to reach limiting values. Only the 3-parameter form of the van Genuchten equation gave stable, meaningful fitting parameters. The 4- and 5-parameter versions were over parameterised, did not always converge to a solution and produced parameter values that were too strongly interdependent to be inferentially useful. The Akaike Information Criterion is used to show that the proposed double exponential equation is better than the 3-parameter van Genuchten equation in the sense of having a smaller information loss relative to “reality” (i.e. the experimental data).

A hydrogen sensor based on tunneling between palladium clusters

We describe nanocluster based tunneling sensors for detecting hydrogen. Pd clusters with diameters ranging from 3.5to6nm are deposited between a pair of contacts until a predetermined resistance between the contacts is obtained. We demonstrate that the conduction through the cluster film is dominated by tunneling gaps. Upon exposure to hydrogen, the clusters expand, reducing the average size of the gaps and reducing the measured resistance. The sensor response as a function of external hydrogen pressure is described, for different cluster sizes and different operating temperatures, by a simple model with a single physically meaningful fitting parameter.

Modeling Np and Pu transport with a surface complexation model and spatially variant sorption capacities: implications for reactive transport modeling and performance assessments of nuclear waste disposal sites

One-dimensional (1D) geochemical transport modeling is used to demonstrate the effects of speciation and sorption reactions on the ground-water transport of Np and Pu, two redox-sensitive elements. Earlier 1D simulations (Reardon, 1981) considered the kinetically limited dissolution of calcite and its effect on ion-exchange reactions (involving 90Sr, Ca, Na, Mg and K), and documented the spatial variation of a 90Sr partition coefficient under both transient and steady-state chemical conditions. In contrast, the simulations presented here assume local equilibrium for all reactions, and consider sorption on constant potential, rather than constant charge, surfaces. Reardon's (1981) seminal findings on the spatial and temporal variability of partitioning (of 90Sr) are reexamined and found partially caused by his assumption of a kinetically limited reaction. In the present work, sorption is assumed the predominant retardation process controlling Pu and Np transport, and is simulated using a diffuse-double-layer-surface-complexation (DDLSC) model. Transport simulations consider the infiltration of Np- and Pu-contaminated waters into an initially uncontaminated environment, followed by the cleanup of the resultant contamination with uncontaminated water. Simulations are conducted using different spatial distributions of sorption capacities (with the same total potential sorption capacity, but with different variances and spatial correlation structures). Results obtained differ markedly from those that would be obtained in transport simulations using constant K d, Langmuir or Freundlich sorption models. When possible, simulation results (breakthrough curves) are fitted to a constant K d advection–dispersion transport model and compared. Functional differences often are great enough that they prevent a meaningful fit of the simulation results with a constant K d (or even a Langmuir or Freundlich) model, even in the case of Np, a weakly sorbed radionuclide under the simulation conditions. Functional behaviors that cannot be fit include concentration trend reversals and radionuclide desorption spikes. Other simulation results are fit successfully but the fitted parameters ( K d and dispersivity) vary significantly depending on simulation conditions (e.g. “infiltration” vs. “cleanup” conditions). Notably, an increase in the variance of the specified sorption capacities results in a marked increase in the dispersion of the radionuclides. The results presented have implications for the simulation of radionuclide migration in performance assessments of nuclear waste-disposal sites, for the future monitoring of those sites, and more generally for modeling contaminant transport in ground-water environments.

Carbon–Chlorine and Carbon–Bromine Bond Cleavage in the Catalytic Hydrodehalogenation of Halogenated Aromatics

The catalytic hydrodehalogenation of chlorobenzene (CB), bromobenzene (BB), CB/BB mixtures, and the three chlorobromobenzene (CBB) isomers was studied over the temperature range 473 K≤T≤603 K using Ni/SiO2 where the Ni loading was varied from 6.2 to 15.2% wt/wt. Each catalyst was 100% selective in terms of hydrodehalogenation and there was no evidence of any aromatic ring reduction. Steady-state conversion was readily achieved but there was a decided decline in activity with prolonged catalyst use. The catalyst samples were characterized, before and after use, by TEM, CO chemisorption/TPD, TPO, and potentiometric analysis. We recorded the levels of reversibly and irreversibly held Cl and/or Br on the spent catalysts. Appreciable Ni particle growth during catalysis was observed and this is attributed to a halide-induced metal agglomeration, while CO TPD revealed a significant disruption to the Ni particle electronic structure. Long-term deactivation is ascribed to a less effective activation of the haloarene and/or hydrogen reactant(s) allied to a halide-promoted carbonaceous deposition; the surface coke is characterized as predominantly amorphous. Reactivity increased in the order 2-CBB<3-CBB<4-CBB<BB<CB, which is taken to be diagnostic of an electrophilic mechanism where the presence of a second electron withdrawing a halogen substituent lowers the overall dehalogenation rate and steric hindrance governs reactivity in the case of the CBB isomers. In the hydrotreatment of CB/BB mixtures and CBB isomers, the fractional debromination increased due to a surface hydrochlorination and Cl exchange with the Br substituent on the aromatic ring. The reaction orders with respect to CB, BB, and H2 were determined, while the experimentally determined rate/pressure profiles were subjected to standard Langmuir–Hinshelwood kinetic modeling. The best overall (meaningful) fit to the experimental data was achieved with a model based on the associative adsorption of the haloarene and the dissociative adsorption of hydrogen on the same sites with no product inhibition.

Carbon–Chlorine and Carbon–Bromine Bond Cleavage in the Catalytic Hydrodehalogenation of Halogenated Aromatics

The catalytic hydrodehalogenation of chlorobenzene (CB), bromobenzene (BB), CB/BB mixtures, and the three chlorobromobenzene (CBB) isomers was studied over the temperature range 473 K≤ T≤603 K using Ni/SiO 2 where the Ni loading was varied from 6.2 to 15.2% wt/wt. Each catalyst was 100% selective in terms of hydrodehalogenation and there was no evidence of any aromatic ring reduction. Steady-state conversion was readily achieved but there was a decided decline in activity with prolonged catalyst use. The catalyst samples were characterized, before and after use, by TEM, CO chemisorption/TPD, TPO, and potentiometric analysis. We recorded the levels of reversibly and irreversibly held Cl and/or Br on the spent catalysts. Appreciable Ni particle growth during catalysis was observed and this is attributed to a halide-induced metal agglomeration, while CO TPD revealed a significant disruption to the Ni particle electronic structure. Long-term deactivation is ascribed to a less effective activation of the haloarene and/or hydrogen reactant(s) allied to a halide-promoted carbonaceous deposition; the surface coke is characterized as predominantly amorphous. Reactivity increased in the order 2-CBB<3-CBB<4-CBB<BB<CB, which is taken to be diagnostic of an electrophilic mechanism where the presence of a second electron withdrawing a halogen substituent lowers the overall dehalogenation rate and steric hindrance governs reactivity in the case of the CBB isomers. In the hydrotreatment of CB/BB mixtures and CBB isomers, the fractional debromination increased due to a surface hydrochlorination and Cl exchange with the Br substituent on the aromatic ring. The reaction orders with respect to CB, BB, and H 2 were determined, while the experimentally determined rate/pressure profiles were subjected to standard Langmuir–Hinshelwood kinetic modeling. The best overall (meaningful) fit to the experimental data was achieved with a model based on the associative adsorption of the haloarene and the dissociative adsorption of hydrogen on the same sites with no product inhibition.

Characterization of beryl (aquamarine variety) by M�ssbauer spectroscopy

The Mossbauer spectra of several blue beryls have been obtained in the temperature range of 4.2–500 K. A common feature observed in all room-temperature spectra is the presence of an asymmetric Fe2+ doublet (ΔE Q ∼ 2.7 mm s−1, δ ∼ 1.1 mm s−1), with a very broad low-velocity peak. This asymmetry seems to be related to a relaxation process involving ferrous ions and water molecules in the structural channels, as suggested by Price et al. (1976). Surprisingly, the spectrum at 500 K also shows a broad, but symmetrical, doublet, with a clear splitting of the lines indicating the presence of at least two Fe2+ components. The room-temperature spectrum obtained after the 500 K run shows the same features as prior to the heating. At 4.2 K the spectrum of a deep blue beryl was well fitted with four symmetrical doublets, one of which could be related to Fe2+ in the structural channels. Ferrous ion was also found to occupy the octahedral and tetrahedral sites, whereas ferric ion is most probably located in the octahedral site. A meaningful fit of the room-temperature spectrum, as well as an explanation for the temperature dependence of the Mossbauer spectra, are discussed. Finally, it is believed that the color in beryl will be dictated by the relative proportions of Fe3+ in the octahedral sites and of Fe2+ in the channels.