Significant Positive Deviation Research Articles

Effects to salt tolerance of GILI tilapia(O.niloticus×S.melanotheron)and its two parents in the chronic salinity stress experiment

In order to further study salt tolerance performance of a hybrid by Oreochromis niloticus(♀)×Sarotherodon melanotheron(♂)which had been examined and approved by China National Aquaculture Variety Approval Committee as a new variety for aquaculture and named tilapiain 2009,researches have been carried out to study the salt tolerance in the chronic salinity stress experiment to GILI tilapia and its two parents,the differences of salt tolerance performance of three kinds of tilapia are analysed,and the regression model between mortality of salt tolerance in the chronic salinity stress and death of time,death of salinity are established.The results of the study show that:(1)There are significant differences in capacity of salt tolerance among three kinds of tilapia,the performance of salt tolerance of GILI tilapia is close to S.melanotheron,it is much higher than O.niloticus,the average death salinity of three kinds of tilapia when they are domesticated in salt are 57.9,66.7 and 18.5 respectively.(2)There are the greatest differences of death time domesticated among individuals in O.niloticus,it is the least in S.melanotheron,it is medium in GILI tilapia.There are the most significant normal negative deviation in GILI tilapia and S.melanotheron,there are the more values of outlier and extremum,O.niloticus has a significant normal positive deviation,it has outlier values,no extremum values.(3)The regression relationships between the mortality of chronic salinity stress to salt and the death time,death salinity of three kinds of tilapia are fit for single-element regression model,the single-element regression model between the salt tolerance mortality(Y)and the domestication time of death(t)and salinity of death(s)of GILI tilapia are growth model Y=e(-7.694+0.031t)(R2=0.979)and quadratic model Y=0.542-0.037s+0.001s2(R2=0.950)respectively.

A comparative study of the volumetric properties of aqueous solutions of pyridine and piperidine derivatives

The objective of this research was to carry out a comparative study of the volumetric properties of 2-pyridinemethanol, 3-pyridinemethanol, 2-(hydroxymethyl)piperidine, and 3-(hydroxymethyl)piperidine in aqueous media. The density and excess volumes of mixing as a function of temperature (T=293.15–318.15K) over the entire concentration range are examined for aqueous solutions of 2,3-pyridinemethanols, and the density and partial molar volumes of aqueous solutions are investigated for the corresponding 2,3-(hydroxymethyl)piperidines. The minimum values of the excess molar volumes, vE, are observed, −0.59cm3mol−1 for 2-pyridinemethanol–water solutions and −0.47 for 3-pyridinemethanol–water solutions. These are about 0.61% and 0.49% respectively, of the molar volume. The thermal expansion coefficients αT at 298.15K calculated from the density data, exhibited significant positive deviations, (about 30%) from ideality for 2-pyridinemethanol–water mixtures, and 3-pyridinemethanol–water mixtures. The partial molar volume of 2,3-(hydroxymethyl)piperidines in water at selected temperatures was evaluated by extrapolating the apparent molar volume versus molality plots to m=0. In addition, the partial molar expansivity, E0, the isobaric coefficient of thermal expansion, αT, the interaction coefficient, Sv, and the Hepler's constant have also been computed. The data are interpreted in terms of the effect of the primary alcohol functional group on the inter/intramolecular and additional hydrophilic interactions between the molecules.

INHERITANCE AND GENE ACTION FOR YIELD AND ITS ATTRIBUTES IN THREE BREAD WHEAT CROSSES (Triticum aestivum L.).

The present investigation was carried out at El-Gemmeiza Agricultural Research station, Agricultural Research Center (ARC), Egypt during four successive seasons from 2007/2008 through 2010/2011. Three crosses were used among five parental varieties, namely P1xP2 (1), P3xP4 (2) and P4xP5 (3) five populations (P1, P2, F1, F2 and F3) for each cross were used in this investigation. Highly significant heterotic values in positive direction were found for all charcters except for plant height and 1000-grain yield in the first cross, spike length in the second cross, and plant height, No. of grains/spike and No. of spikes/plant in the third cross. Over domenance for all characters except plant height and 1000-grain weight in the first cross, spike length in the second cross and No.of grains /spike in the third cross was detected. Inbreeding depression was obtained in two out of three crosses for spike length, No.of grains/spike, No.of spikes/plant, 1000-grain weight and grain yield/plant and in one out of the three crosses for plant height. The important roles of both additive and non-additive gene actionwere found in certain studied traits. Significant positive F2 deviation (E1) were indicated for plant height in the third cross, No.of spikes/pant and grain yield/plant in the second and third crosses and 1000-grain weight in the first and third crosses. High to medium values of heritability estimates were found to be associated with high and moderate expected and actual gain in most traits. These obtained results indicated that, these traits could be used in the early generations, but would be more effective if postponed to late generations.

Radiative power in Tore Supra and its link with Zeff

In this paper, a database of L-mode plasmas with Greenwald density fractions smaller than 0.8 is used to analyse the parametric dependences of the radiative power and the effective charge Zeff. It is found that the radiative power has a linear dependence on the total power and a linear fit is derived.In order to understand this parametric dependence, the changes in the radial extension of the radiation are studied with the help of bolometry measurements and it is found that the increase in Prad with Ptot can be explained by an increase in the neutral source of impurities (basically carbon erosion) during additional heating. A comparison of deuterium and helium plasmas shows that they radiate the same amount at the same total power. Significant positive deviations from the fit of the radiative power are observed for high ratios of Cu XIX/⟨ne⟩. Zeff is also found to depend roughly linearly on the total power. The link found between Zeff and Prad is compatible with that of multimachine scaling (Matthews et al 1997 J. Nucl. Mater. 241–243 450). These results are obtained in a limiter machine, running in L-mode in the case where carbon is the dominant impurity.

A fundamental study of chitosan/PEO electrospinning

A highly deacetylated (97.5%) chitosan in 50% acetic acid was electrospun at moderate temperatures (25–70 °C) in the presence of a low content of polyethylene oxide (10 wt% PEO) to beadless nanofibers of 60–80 nm in diameter. A systematic quantitative analysis of the solution properties such as surface tension, conductivity, viscosity and acid concentration was conducted in order to shed light on the electrospinnability of this polysaccharide. Rheological properties of chitosan and PEO solutions were studied in order to explain how PEO improves the electrospinnability of chitosan. Positive charges on the chitosan molecule and its chain stiffness were considered as the main limiting factors for electrospinability of neat chitosan as compared to PEO, since surface tension and viscosity of the respective solutions were similar. Various blends of chitosan and PEO solutions with different component ratios were prepared (for 4 wt% total polymer content). A significant positive deviation from the additivity rule in the zero shear viscosity of chitosan/PEO blends was observed and believed to be a proof for strong hydrogen bonding between chitosan and PEO chains, making their blends electrospinnable. The impact of temperature and blend composition on the morphology and diameter of electrospun fibers was also investigated. Electrospinning at moderate temperatures (40–70 °C) helped to obtain beadless nanofibers with higher chitosan content. Additionally, it was found that higher chitosan content in the precursor blends led to thinner nanofibers. Increasing chitosan/PEO ratio from 50/50 to 90/10 led to a diameter reduction from 123 to 63 nm. Producing defect free nanofibrous mats from the electrospinning process and with high chitosan content is particularly promising for antibacterial film packaging and filtration applications.

Activities of the components in a spinel solid solution of the Fe-Al-O system

The conditions of the equilibrium between the Fe3O4-FeAl2O4 solution and wustite are determined by measuring the EMF of galvanic cells containing a solid electrolyte, and the activities of the components in the Fe3O4-FeAl2O4 solution are calculated by treating the results of the experiment on the equilibrium between the spinel solution and wustite. Their properties are found to be different from those of ideal solutions at temperatures of 1000–1300 K. A significant positive deviation from the Raoult’s law is believed to indicate the tendency of the solution to decompose. The experimental data are treated in terms of the theory of regular solutions, assuming the energy of mixing to be a function of temperature only. The critical temperature of decomposition for the Fe3O4-FeAl2O4 solution is found to be 1084 K.

Airborne lidar observations in the inflow region of a warm conveyor belt

AbstractWarm conveyor belts (WCBs) are key flow structures associated with extratropical cyclones. They transport moist air from the cyclone's warm sector poleward and upward close to the tropopause level, leading to the formation of elongated cloud bands, intense latent heating and surface precipitation. In this study a comprehensive dataset of airborne lidar observations of moisture and wind from different campaigns has been investigated with a trajectory‐based approach to identify ‘lucky encounters’ with WCBs. On 19 July 2007, an upstream flight over the Iberian Peninsula during the European THORPEX Regional Campaign (ETReC 2007) in Central Europe intersected two WCBs: one in the upper tropospheric outflow region about 3 days after starting the ascent, and the other one in the boundary layer inflow region over Spain just prior to the strong ascent. Comparison of the lidar humidity measurements with analysis fields from the European Centre for Medium‐Range Weather Forecasts (ECMWF) reveals significant positive deviations, equivalent to an overestimation of the modelled humidity, in this low‐tropospheric WCB inflow region (of about 1 g kg−1 (14%) on average and with peak deviations up to 7 g kg−1). It is noteworthy that this substantial bias occurs in a potentially dynamically highly relevant air mass that will be subsequently lifted within a WCB to the upper troposphere. A Lagrangian moisture source diagnostic reveals that these large moisture deviations occur within air masses that, according to the ECMWF analyses, are coherently transported from the western Mediterranean towards Spain and experience intense moisture uptake over the Ebro valley. It is suggested that inaccuracies in surface evapotranspiration, horizontal moisture advection, and turbulent vertical transport of moisture in the atmospheric boundary layer potentially contribute to the erroneous low‐tropospheric humidity in the inflow region of this particular summertime WCB over Spain in the ECMWF analyses. Copyright © 2011 Royal Meteorological Society

Origin and correction of the deviations in retention times at increasing flow rate with Chromolith columns

Chromoliths can be used at flow rates beyond those feasible for conventional microparticulate packed columns. Ideally, the plots of the retention time versus the inverse of delivered flow rate should exhibit y-intercept of zero. However, significant positive deviations correlating with the solute polarity were observed for several compounds chromatographed with a Chromolith column, owing to the increased system pressure. Consequently, the dead time marker exhibits a smaller deviation, making the retention factors depend on the flow rate. Chromoliths are made of a silica-based monolith encapsulated within a PEEK tube, and should suffer larger stress with pressure than stainless steel columns, tending to inflate them and increase their volume. This decreases the linear velocity inside the column, and increases the retention at relatively low pressure (<200 bar). In contrast, frictional heating, which is an issue for microparticulate columns, seems to be less significant for the highly permeable Chromoliths. The usefulness of the retention time versus the inverse of the delivered flow rate plots to measure the deviations, whatever their origin, is shown. This allows the correction of the retention times to the ideal behaviour, where the retention factors are independent of the flow rate.

Effect of ground cover vegetation on the abundance and diversity of beneficial arthropods in citrus orchards

The effect of ground cover upon the communities of beneficial arthropods established in the canopy of lemon trees was investigated, by comparing three ground-cover management treatments applied: RV, resident vegetation; S, sowed selected species; and BS, bare soil by controlling weeds with herbicide. Over two consecutive years, arthropod communities in the tree canopy were sampled periodically by beating and suction techniques. Significantly higher numbers of beneficial arthropods were found in the RV and S treatments in comparison with bare soil. Spiders and parasitoid wasps were the two most common groups, representing, respectively, 70% and 19% of all catches in beating samples and 33% and 53% in suction samples. For the RV and S treatments, significant seasonal deviations from the bare soil treatment were observed using principal response curves. Similar seasonal patterns were observed over the two years. The RV and S treatments showed significant positive deviations from the BS treatment in late spring and summer, accounted for the higher numbers of parasitoid wasps, coccinelids and lacewings present. By contrast, the seasonal deviations observed for the spider community differed from those of the remaining arthropods. During late winter and early spring, the RV and S treatments presented a higher abundance of spiders in the tree canopy, in comparison with bare soil, whereas in the summer significantly more spiders were found in the bare soil treatment. Spider movements between tree canopy and ground vegetation layers may justify this result.

A COSMO-RS based guide to analyze/quantify the polarity of ionic liquids and their mixtures with organic cosolvents

A COSMO-RS descriptor (S(sigma-profile)) has been used in quantitative structure-property relationship (QSPR) studies by a neural network (NN) for the prediction of empirical solvent polarity E(T)(N) scale of neat ionic liquids (ILs) and their mixtures with organic solvents. S(sigma-profile) is a two-dimensional quantum chemical parameter which quantifies the polar electronic charge of chemical structures on the polarity (sigma) scale. Firstly, a radial basis neural network exact fit (RBNN) is successfully optimized for the prediction of E(T)(N), the solvatochromic parameter of a wide variety of neat organic solvents and ILs, including imidazolium, pyridinium, ammonium, phosphonium and pyrrolidinium families, solely using the S(sigma-profile) of individual molecules and ions. Subsequently, a quantitative structure-activity map (QSAM), a new concept recently developed, is proposed as a valuable tool for the molecular understanding of IL polarity, by relating the E(T)(N) polarity parameter to the electronic structure of cations and anions given by quantum-chemical COSMO-RS calculations. Finally, based on the additive character of the S(sigma-profile) descriptor, we propose to simulate the mixture of IL-organic solvents by the estimation of the S(sigma-profile)(Mixture) descriptor, defined as the weighted mean of the S(sigma-profile) values of the components. Then, the E(T)(N) parameters for binary solvent mixtures, including ILs, are accurately predicted using the S(sigma-profile)(Mixture) values from the RBNN model previously developed for pure solvents. As result, we obtain a unique neural network tool to simulate, with similar reliability, the E(T)(N) polarity of a wide variety of pure ILs as well as their mixtures with organic solvents, which exhibit significant positive and negative deviations from ideality.

Thermodynamic properties of aqueous solutions of pyridine and piperidine

This research was designed to examine the thermodynamic properties of aqueous solutions of pyridine and piperidine. The density, excess molar enthalpy of mixing, H E, and excess molar volume of mixing, v E of piperidine–water and pyridine–water mixtures were studied at three temperatures, ranging from 294 K to 315 K. The H E and v E are negative for both mixtures, minimizing at a water mole fraction of about 0.55. The minimum H E for piperidine–water mixtures is −2.23 kJ/mol which is compared with −1.63 kJ/mol for pyridine–water mixtures. The minimum v E are about −1.7 cm 3/mol and −0.7 cm 3/mol for piperidine–water and pyridine–water mixtures, respectively. The thermal expansion coefficients α T at 303 K, calculated from the density studies, exhibited significant positive deviations (about 20%) from ideality for piperidine–water mixtures. In contrast to this pyridine–water α T only exhibited small positive deviations from ideality of about 2%. The results predict decreases in the absolute magnitude of v E with an increase in temperature which are 5. × 10 −3 cm 3/K mol and 1. × 10 −3 cm 3/K mol, for piperidine–water and pyridine–water mixtures, respectively. The results for v E for piperidine–water mixtures agree with the very precise work of Afzal et al., J. Chem. Thermodyn. 40 (2008) 47–53. The data are interpreted in terms of the greater number of opportunities for hydrogen bonding interactions between the unlike molecules for the piperidine–water mixtures.

Distributional Properties and Deviations of Transaction Sizes in U.S. Equities

In order to get a comprehensive understanding of the market dynamics, we need to investigate the relationship between price and volume. However, it is a well known fact that it takes volume to move prices. We analyze the transaction data of S&amp;P 500 stocks and found that the transaction size displays a power-law decay and can be characterized by an exponent within the stable Levy domain. Further more, most interestingly there are significant positive deviations at transaction sizes of 100, 500, 1000, 1500, 2000, 2500, 3000, 4000, 5000, 6000, …, 10000, for the S&amp;P 500 companies. In other words, there are more trades at above trade sizes than anticipated by the Pareto distribution. <b>TOPICS:</b>Statistical methods, volatility measures, exchanges/markets/clearinghouses

Resonant Raman scattering contribution to attenuation of x rays at energies in lower vicinity of the K-shell ionization threshold of some elements

Attenuation of the x rays and γ rays in the T22i, N41b, T69m, Y70b, and L71u elements have been measured with special emphasis for the x ray energies (Ein) in lower vicinity of the K shell ionization threshold (BK) of the element. The incident photon beam is obtained from decay of the F55e, A241m, and C57o radioisotopes, and fluorescence of the V23, Y70b, L71u, W74, O76s, and T90h targets excited by the x rays and γ rays from the radioisotopes. The measurements were performed using energy dispersive setups involving Ge detectors. The measured attenuation coefficients agree with the available theoretical values except at the photon energies with (BK-Ein) less than or nearly equal to the K-shell width (ΓK), where significant positive deviations as large as factor of 2 have been observed. In view of reliability of the available theoretical cross sections for the photoionization and the photon scattering processes, the magnitude of positive alteration at the photon energy in lower vicinity of the ionization threshold is attributed to the K shell resonant Raman scattering (RRS) process and the corresponding cross sections have been deduced. Possible matrix effects in the energy dispersive x ray spectrometry due to RRS are also discussed.

Relation between lipophilicity of alkyl gallates and antifungal activity against yeasts and filamentous fungi

The antifungal activity of a complete series of 15 n-alkyl gallates and six analogues acting against a representative panel of opportunistic pathogenic fungi was studied in order to analyze their role in: the importance of the fungi tested, the importance of the hydroxyls, the influence of the chain length and the hydrophobicity of the compounds. It was demonstrated that dermatophytes were the most susceptible species and that hydroxyls appear to be necessary but not sufficient for the activity. When the log P of each gallate was calculated and related to the different values of MIC against Microsporum gypseum it was observed that hexyl, heptyl, octyl and nonyl gallates exhibit a significant positive deviation from the curve corresponding to a polynomial equation obtained for the other gallates. This suggests that these compounds have a further mode of action besides their hydrophobicity, possibly the inhibition of some enzyme involved in ergosterol biosynthesis.

Mid-Pliocene equatorial Pacific sea surface temperature reconstruction: a multi-proxy perspective

The Mid-Pliocene is the most recent interval of sustained global warmth, which can be used to examine conditions predicted for the near future. An accurate spatial representation of the low-latitude Mid-Pliocene Pacific surface ocean is necessary to understand past climate change in the light of forecasts of future change. Mid-Pliocene sea surface temperature (SST) anomalies show a strong contrast between the western equatorial Pacific (WEP) and eastern equatorial Pacific (EEP) regardless of proxy (faunal, alkenone and Mg/Ca). All WEP sites show small differences from modern mean annual temperature, but all EEP sites show significant positive deviation from present-day temperatures by as much as 4.4 degrees C. Our reconstruction reflects SSTs similar to modern in the WEP, warmer than modern in the EEP and eastward extension of the WEP warm pool. The east-west equatorial Pacific SST gradient is decreased, but the pole to equator gradient does not change appreciably. We find it improbable that increased greenhouse gases (GHG) alone would cause such a heterogeneous warming and more likely that the cause of Mid-Pliocene warmth is a combination of several forcings including both increased meridional heat transport and increased GHG.

Spatial Pattern of Coast Redwood in Three Alluvial Flat Old-Growth Forests in Northern California

Abstract The spatial patterns of trees were investigated in old-growth redwood (Sequoia sempervirens [D. Don] Endl.) forests located in northern California to guide the design of restoration prescriptions. All stems ≥15 cm dbh were mapped and measured on three 1.5-ha plots. Patterns for trees in different size classes were analyzed separately with Ripley's K(d) function. Results revealed two patterns. At two sites, trees were randomly distributed throughout the stand and size classes were spatially independent of each other at scales of 0–50 m. At one site, a clumped spatial pattern was revealed for small- and medium-sized tree groups at small scales, whereas a random spatial pattern was detected for large trees at scales of 0–50 m. In addition, significant positive deviation from spatial independence at small scales suggested an attraction between tree groups. The spatial pattern of regeneration (trees &amp;lt;15 cm dbh) was described using quadrat-based analyses. Regeneration was clumped at all three sites. Results indicate that old-growth redwood forests occurring on alluvial flats have different spatial patterns for similar size classes of trees despite the similarities in topography and stand structural characteristics. For land managers interested in restoration, these results suggest that past thinning guides that emphasized uniform spacing may not be appropriate in restoration efforts. Instead, trees should be retained in clumps or in random spatial patterns.

Thermodynamic activities in the Pb(Zr 1− XTi X)O 3 solid solution at 1373 K

Although Pb(Zr 1− X Ti X )O 3 solid solution is the cornerstone of the piezoelectric ceramics, there is no information in the literature on thermodynamic activities of the component phases in the solid solution. Using inter-crystalline ion exchange equilibria between Pb(Zr 1− X Ti X )O 3 solid solution with cubic perovskite structure and (Zr 1− Y Ti Y )O 2 solid solutions with monoclinic and tetragonal structures, activities of PbTiO 3 and PbZrO 3 in the perovskite solid solution have been derived at 1373 K using the modified Gibbs–Duhem integration technique of Jacob and Jeffes. Tie-lines from the cubic solid solution are skewed towards the ZrO 2 corner. Activities in the zirconia-rich (Zr 1− Y Ti Y )O 2 solid solutions are taken from a recent emf study. The results for the perovskite solid solution at 1373 K can be represented by a sub-regular solution model: Δ G E , M ( J mo l − 1 ) = X PbTi O 3 X PbZr O 3 ( 15280 X PbTi O 3 − 1980 X PbZr O 3 ) where Δ G E,M is the excess Gibbs energy of mixing of the cubic solid solution and X i represents the mole fraction of component i. There is a significant positive deviation from ideality for PbTiO 3-rich compositions and mild negative deviation near the PbZrO 3 corner. The cubic solid solution is intrinsically stable against composition fluctuations at temperatures down to 840 K. The results contrast sharply with the recent calorimetric data on enthalpy of mixing which signal instability of the cubic perovskite solid solution.

Ridership Accuracy and Transit Formula Grants

The accuracy of annual unlinked passenger trips reported to the National Transit Database (NTD) at the agency level is examined by using a two-step approach. The first step compares ridership reported to the American Public Transportation Association (APTA) with ridership reported to NTD. NTD ridership can be as high as 50% more than APTA rider-ship, and such significant positive deviation exists persistently over time across many agencies. The second step explores potential sources of these deviations by examining their components. Random errors, including both sampling errors and some of the nonsampling errors, do not help explain these one-sided deviations, nor do occasional annual adjustments, such as special-events ridership in the NTD ridership. Much of this deviation appears to be attributable to systematic nonsampling sources that result from undercounting in direct counts, from unintentional biases in procedures, or perhaps from intentional manipulation. Although mechanisms and incentives exist f...

Ridership Accuracy and Transit Formula Grants

The accuracy of annual unlinked passenger trips reported to the National Transit Database (NTD) at the agency level is examined by using a two-step approach. The first step compares ridership reported to the American Public Transportation Association (APTA) with ridership reported to NTD. NTD ridership can be as high as 50% more than APTA ridership, and such significant positive deviation exists persistently over time across many agencies. The second step explores potential sources of these deviations by examining their components. Random errors, including both sampling errors and some of the nonsampling errors, do not help explain these one-sided deviations, nor do occasional annual adjustments, such as special-events ridership in the NTD ridership. Much of this deviation appears to be attributable to systematic nonsampling sources that result from undercounting in direct counts, from unintentional biases in procedures, or perhaps from intentional manipulation. Although mechanisms and incentives exist for these sources, there is little evidence for any one specific source. How systematic errors could affect the allocation of two formula grants to Florida transit agencies—the Urbanized Area Formula Grant Program and Florida's Transit Block Grant Program—is quantitatively examined. A strategy for reducing systematic errors is also discussed.

Mixed monolayers involving DPPC, DODAB and oleic acid and their interaction with nicotinic acid at the air–water interface

The behaviour of binary mixtures involving dipalmitoylphosphatidylcholine (DPPC), dioctadecyldimethylammonium bromide (DODAB) and oleic acid (OA) was investigated at the air–water interface by surface pressure–area ( π– A) measurements and by Brewster angle microscopy (BAM). Thermodynamic analysis indicates for the system DPPC/DODAB miscibility with strong negative deviations from the ideal behaviour, from low to high surface pressures over all the composition range. For systems DODAB/OA and DPPC/OA, thermodynamic analysis and BAM observation indicate miscibility from low to intermediate surface pressures, and phase separation in a limited range of composition at high surface pressures. The interaction of nicotinic acid (NA) with pure lipids and with selected compositions of mixed systems was investigated. Significant positive deviations of π– A isotherms in the presence of NA indicate attractive interactions between NA and the polar groups of DPPC and DODAB. NA easily penetrates in expanded regimes while it tends to be segregated from condensed regimes in mixed monolayers.