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Solitary and Periodic Exact Solutions Of the Viscosity-capillarity van der Waals Gas Equations
Get PDFPeriodic and soliton solutions are derived for the (1+1)-dimensional van der Waals gas system in the viscosity-capillarity regularization form. The system is handled via the e-φ(ξ) -expansion method. The obtained solutions have been articulated by the hyperbolic, trigonometric, exponential and rational functions with arbitrary constants. Mathematical analysis and numerical graphs are provided for some solitons, periodic and kink solitary wave solutions to visualize the dynamics of equations. Obtained results reveal that the method is very influential and effective tool for solving nonlinear partial differential equations in applied mathematics
Soil physical properties spatial variability under long-term no-tillage corn
No full textSpatial variability of soil physical and hydrological properties within or among agricultural fields could be intrinsically induced due to geologic and pedologic soil forming factors, but some of the variability may be induced by anthropogenic activities such as tillage practices. No-tillage has been gaining ground as a successful conservation practice, and quantifying spatial variability of soil physical properties induced by no-tillage practices is a prerequisite for making appropriate site-specific agricultural management decisions and/or reformulating some management practices. In particular, there remains very limited information on the spatial variability of soil physical properties under long-term no-tillage corn and tropical soil conditions. Therefore, the main objective of this study was to quantify the spatial variability of some selected soil physical properties (soil surface temperature (ST), volumetric water content (θv), soil resistance (TIP), total porosity (θt), bulk density (ρb), organic carbon, and saturated hydraulic conductivity (Ksat)) using classical and geostatistical methods. The study site was a 2 ha field cropped no-tillage sweet corn for nearly 10 years on Oahu, Hawaii. The field was divided into 10 × 10 and 20 × 20 m grids. Soil samples were collected at each grid for measuring ρb, θt, and soil organic carbon (SOC) in the laboratory following standard methods. Saturated hydraulic conductivity, TIP at 10 and 20 cm depths, soil surface temperature, and θv were also measured. Porosity and ρb have low and low to moderate variability, respectively based on the relative ranking of the magnitude of variability drawn from the coefficient of variation. Variability of the SOC, TIP, and Ksat ranges from moderate to high. Based on the best-fitted semivariogram model for finer grid data, 9.8 m and 142.2 m are the cut off beyond which the measured parameter does not show any spatial correlation for SOC, and TIP at 10 cm depth, respectively. Bulk density shows the highest spatial dependence (range = 226.8 m) among all measured properties. Spatial distribution of the soil properties based on kriging shows a high level of variability even though the sampled field is relatively small
The sociotechnical axis of cohesion for the IS discipline: Its historical legacy and its continued relevance
No full textThe sociotechnical perspective is often seen as one of the foundational viewpoints—or an “axis of cohesion”—for the Information Systems (IS) discipline, contributing to both its distinctiveness and its ability to coherently expand its boundaries. However, our review of papers in the two leading IS journals from 2000 to 2016 suggests that IS research has lost sight of the discipline’s sociotechnical character—a character that was widely acknowledged at the discipline’s inception. This is a problem because an axis of cohesion can be fundamental to a discipline’s long-term vitality. In order to address this issue, we offer ways to renew the sociotechnical perspective so that it can continue to serve as a distinctive and coherent foundation for the discipline. Our hope is that the renewed sociotechnical frame for the IS discipline discussed in the paper holds potential to contribute to the enduring strength of our diverse, distinctive, yet unified discipline. It also prompts members of the discipline to think more deeply about what it means to be an IS scholar
Heterogeneous beliefs and volatility smile
No full textFriesen et al. demonstrate that investor heterogeneous beliefs affect option prices and explain the risk neutral skewness. Following their study, this paper examines the cross-sectional relation between heterogeneous beliefs and the option implied volatility smile. Examining the impact of heterogeneous beliefs on puts and calls separately produces more insights on the effect of heterogeneous beliefs on option prices. The paper finds that stocks with greater belief differences have more pronounced volatility smiles steeper put slopes and steeper call slopes. These results confirm the findings of Friesen, Zhang and Zorn (2012) that investor heterogeneous beliefs affect option prices and further demonstrate this impact is same for puts and calls. This study also suggests that empirical studies of heterogeneous beliefs are robust to various measures of option prices
Uncovering sperm metabolome to discover biomarkers for bull fertility
No full textBackground: Subfertility decreases the efficiency of the cattle industry because artificial insemination employs spermatozoa from a single bull to inseminate thousands of cows. Variation in bull fertility has been demonstrated even among those animals exhibiting normal sperm numbers, motility, and morphology. Despite advances in research, molecular and cellular mechanisms underlying the causes of low fertility in some bulls have not been fully elucidated. In this study, we investigated the metabolic profile of bull spermatozoa using non-targeted metabolomics. Statistical analysis and bioinformatic tools were employed to evaluate the metabolic profiles high and low fertility groups. Metabolic pathways associated with the sperm metabolome were also reported. Results: A total of 22 distinct metabolites were detected in spermatozoa from bulls with high fertility (HF) or low fertility (LF) phenotype. The major metabolite classes of bovine sperm were organic acids/derivatives and fatty acids/conjugates. We demonstrated that the abundance ratios of five sperm metabolites were statistically different between HF and LF groups including gamma-aminobutyric acid (GABA), carbamate, benzoic acid, lactic acid, and palmitic acid. Metabolites with different abundances in HF and LF bulls had also VIP scores of greater than 1.5 and AUC- ROC curves of more than 80%. In addition, four metabolic pathways associated with differential metabolites namely alanine, aspartate and glutamate metabolism, β-alanine metabolism, glycolysis or gluconeogenesis, and pyruvate metabolism were also explored. Conclusions: This is the first study aimed at ascertaining the metabolome of spermatozoa from bulls with different fertility phenotype using gas chromatography-mass spectrometry. We identified five metabolites in the two groups of sires and such molecules can be used, in the future, as key indicators of bull fertility
Statistical Interaction Description of Pauli Crystals in 2D Systems of Harmonically Confined Fermions
No full textIt is conjectured that the Pauli exclusion principle alone may be responsible for a particular geometric arrangement of confined systems of identical fermions even when there is no interaction between them. These geometric structures, called Pauli crystals, are predicted for a two-dimensional (2D) system of free fermions under harmonic confinement. In this work, the possibility of this outcome is pursued and a theoretical model is considered that may capture both qualitatively and quantitatively, the key features of the abovementioned setup. The results for (Formula presented.) and 6 particles show that the minimum energy configuration corresponds to and is in good quantitative agreement with the reported values of Pauli crystals seen in single-shot imaging data obtained via the configuration density technique. Numerical results for larger systems of (Formula presented.) and 30 particles show that the crystalline configurations observed are not the same as the classical Wigner crystal structures that emerge should the confined charged particles interact with a Coulomb potential. An important question floated is whether such crystalline structures do really exist in a quantum system or whether they are artifacts of the methods used to analyze them
Exact results for a quantum Hall state with broken rotational symmetry
No full textThe most robust fractional quantum Hall state in a strongly correlated two-dimensional system of electrons occurs at one-third filling factor of the lowest Landau level. This state is characterized as an isotropic quantum liquid phase of electrons and is well-described by Laughlin\u27s wave function. The possibility of anisotropic liquid phases of electrons at various filling factors has also been considered via many-body trial wave functions that do not possess rotational symmetry. Several studies employing different approaches and computational methods have been carried out. The inherent many-body nature of a wave function with broken rotational symmetry makes it very cumbersome for analytic calculations. In this work we succeeded to calculate exactly the total energy per particle and all other relevant quantities that correspond to a quantum system of two electrons at one-third filling factor described by a wave function with broken rotational symmetry. The results obtained serve as benchmarks to gauge the accuracy of various numerical methods and simulation techniques used to study the properties of strongly correlated electronic systems of this nature
The Influence of Thermal Radiation on MHD Tangent Hyperbolic Fluid Flow with Zero Normal Flux of Nanoparticles over an Exponential Stretching Sheet
Get PDFThis article presents the two-dimensional MHD flow of tangent hyperbolic fluid with zero normal flux of nano-particles over an exponentially stretching sheet in presence of thermal radiation. The governing system of non-linear partial differential equations along with boundary conditions for this fluid flow is converted into a system of non-linear ordinary differential equations by using appropriate similarity transformations. The reduced system is numerically solved by Runge-Kutta fourth order method with shooting technique. The effects of emerging non-dimensional parameters on velocity, temperature and nanoparticle volume fraction profiles have been discussed and presented graphically. Furthermore, the impacts of these parameters on skin friction coefficient and local Nusselt number at the sheet are exhibited and discussed. Noticed that the thermal boundary layer thickness enhanced with the increase in Weissenberg number, power-law index and radiation parameter whereas the velocity profiles and the skin friction coefficient decreases with an increase in Weissenberg number and power-law index
Radiation effect on mixed convection flow of nanofluid between two concentric cylinders with Hall and Ion-slip effects
Get PDFThis paper analyzes the effects of thermal radiation, Hall and ion slip parameter on mixed convective nanofluid flow in an annuli between two concentric cylinders in the existence of strong magnetic field. The nonlinear governing equations are non-dimensionalized and then solved by using homotopy analysis method. The influence of radiation, magnetic, Hall and ion slip parameters on the velocity, temperature, nanoparticle concentration, Nusselt number and nanoparticle Sherwood number are investigated and represented graphically