We report a direct observation on the laterally emitted surface second harmonic generation (SHG) in a single ZnTe nanowire. The highly directional surface SHG radiates vertically to the nanowire growth-axis with a high conversion efficiency of 5 × 10(-6) and a low divergence angle of 4°. Polarization state, emission intensity, and direction of the surface SHG are found to be dependent on the po...

Phyllotaxis, the regular arrangement of leaves or flowers around a plant stem, is an example of developmental pattern formation and organogenesis. Phyllotaxis is characterized by the divergence angles between the organs, the most common angle being 137.5°, the golden angle. Models of phyllotaxis must explain its de novo establishment in the radially symmetric embryo, the stable maintenance of t...

Abstract. An interesting phenomenon about phyllotaxis is the divergence angle between two consecutive primordia. In this paper, we consider a dynamic model based on Max-Min principle for generating 2D phyllotactic patterns studied in [2, 5]. Under the hypothesis that the influence of the two predecessors is enough to fix the birth place of the new generated primordium, analysis and numerical ex...

We discuss the approximation properties of divergence-free vector fields by using trivariate spline vectors which are also divergence-free. We pay special attention to the approximation constants and show that they depend only on the smallest solid angle in the underlying tetrahedral partition and the nature of the boundary of the domain. The estimates are given in the max-norm and L norm. §

Introduction Several surgical techniques emphasizing sutures on the lower lateral cartilage have been studied by surgeons as instruments to improve nasal tip remodeling. It is already known that the domal divergence angle and its definition angle can be modified by lateral intercrural suture (LIS). Techniques for measuring these structures are not yet standardized. Objectives Assess the efficac...

1: Seeds of sunflowers are often modelled by the map n 7−→ φθ(n) = √ ne2iπnθ leading to a roughly uniform repartition with two consecutive seeds separated by the divergence angle 2πθ for θ the golden ratio. We associate to an arbitrary real divergence angle 2πθ a geodesic path γθ : R>0 −→ PSL2(Z)\H of the modular curve and use it for local descriptions of the image φθ(N) of the phyllotactic map...

Faraday probe measurements were taken in the near-field plume of a 6-kW Hall thruster to reduce the negative effects of facility-induced charge-exchange collisions. The results from these measurements were analyzed using a non-standard definition of the current density integration bounds that produced self-consistent beam current and beam divergence values. The measurements indicated a beam div...

in a control structures, it is often preferred to minimize the gate width while utilizing the canal width in full for a stilling basin. therefore, to reach this, a gradually diverging stilling basin may be used. in this study, the effect of broad-crested sill on the expanding hydraulic jump in a rectangular channel was investigated. a total number of 79 tests were carried out for the range of i...

Directed cell migration is critical to a variety of biological and physiological processes. Although simple topographical patterns such as parallel grooves and three-dimensional post arrays have been studied to guide cell migration, the effect of the dimensions and shape of micropatterns, which respectively represent the amount and gradient of physical spatial cues, on cell migration has not ye...