Effect of soil moisture management on the quality of wax apple

Wax apple (Syzygium samarngense Merr.et Perry) was one of the economically planted fruits in Taiwan. This research was conducted to evaluate the effects of different soil moisture management on increasing wax apple quality. It was preceded at two different soil properties (shallow soil and alluvial soil) in Pingtung, Taiwan. Three different treatments were used at the two areas in the fruit setting stage: (1) the soil was furrowed 20 cm and immersed in water (5 cm) (FI); (2) soil moisture was monitored by tensiometer, from 15 to 25 cbar (TM); (3) Drought (DR) and the treatment of farmer usage as check (FU). The results show that the effect of TM treatment on soil available elements, the concentration of leaf elements and fruit color were all highest, and the fruit cracking percentage was lower than in other treatments in shallow soil. On the other hand, the effect of FI treatment on soil available elements, the concentration of leaf elements and fruit color were all highest, and the fruit cracking percentage was lower than for other treatments in alluvial soil. To improve the quality of wax apple, it may be treated by different management of soil moisture for the two kinds of soils at the fruit setting stage.Keywords: Wax apple, soil moisture, nutrition, fruit quality, fruit cracking.African Journal of BiotechnologyVol. 12(42), pp. 6107-611

Permanence for a Discrete Model with Feedback Control and Delay

The permanence of a single-species population discrete model with feedback control is considered. We found that if we use the method of comparison theorem, then the additional condition, to some extent, is necessary. But for the system itself, this condition may not be necessary. Here, we use new methods instead of the comparison theorem to get the permanence of the system in consideration; the additional condition in Chen's paper (2007) is deleted

Poly[[penta­aqua­(μ4-pyridine-2,4,6-tri­carboxyl­ato)(μ3-pyridine-2,4,6-tri­carboxyl­ato)disamarium(III)] mono­hydrate]

The asymmetric unit of the title compound, {[Sm2(C8H2NO6)2(H2O)5]·H2O}n, contains two independent SmIII ions, two pyridine-2,4,6-tricarboxyl­ate (ptc) ligands, five aqua ligands and one lattice water mol­ecule. One SmIII ion is nine-coordinated by one N and five O atoms from the three ptc ligands and three aqua ligands in a distorted monocapped square antiprismatic geometry, and the other is eight-coordinated by one N and five O atoms from three ptc ligands and two aqua ligands in a 4,4′-bicapped trigonal anti­prismatic geometry. The ptc ligands brigde the SmIII ions into a three-dimensional polymeric framework. Extensive O—H⋯O hydrogen bonding is observed in the crystal structure

Linear B-spline finite element method for the improved Boussinesq equation

In this paper, we develop and validate a numerical procedure for solving a class of initial boundary value problems for the improved Boussinesq equation. The finite element method with linear B-spline basis functions is used to discretize the nonlinear partial differential equation in space and derive a second order system involving only ordinary derivatives. It is shown that the coefficient matrix for the second order term in this system is invertible. Consequently, for the first time, the initial boundary value problem can be reduced to an explicit initial value problem to which many accurate numerical methods are readily applicable. Various examples are presented to validate this technique and demonstrate its capacity to simulate wave splitting, wave interaction and blow-up behavior

2,2′-{[4,6-Bis(octyl­amino)-1,3,5-triazin-2-yl]aza­nedi­yl}diethanol

In the title compound, C23H46N6O2, the two hy­droxy groups are located on opposite sides of the triazine ring. One of the hy­droxy groups links with the triazine N atom via an intra­molecular O—H⋯N hydrogen bond. Inter­molecular O—H⋯N and N—H⋯O hydrogen bonding is observed in the crystal structure. π–π stacking is also observed between parallel triazine rings of adjacent mol­ecules, the centroid–centroid distance being 3.5944 (14) Å

On a Generalized Discrete Ratio-Dependent Predator-Prey System

Verifiable criteria are established for the permanence and existence of positive periodic solutions of a delayed discrete predator-prey model with monotonic functional response. It is shown that the conditions that ensure the permanence of this system are similar to those of its corresponding continuous system. And the investigations generalize some well-known results. In particular, a more acceptant method is given to study the bounded discrete systems rather than the comparison theorem

Optimal control computation for nonlinear systems with state-dependent stopping criteria

In this paper, we consider a challenging optimal control problem in which the terminal time is determined by a stopping criterion. This stopping criterion is defined by a smooth surface in the state space; when the state trajectory hits this surface, the governing dynamic system stops. By restricting the controls to piecewise constant functions, we derive a finite-dimensional approximation of the optimal control problem. We then develop an efficient computational method, based on nonlinear programming, for solving the approximate problem. We conclude the paper with four numerical examples

A New Computational Method for Optimizing Nonlinear Impulsive Systems

In this paper, we consider a system that evolves by switching between several subsystems of ordinary differential equations. The switching mechanism is this system induces an instantaneous change in the system's state, which can be controlled through a set of decision parameters. We develop a new computational method, based on nonlinear programming, for optimizing the system parameters and the subsystem switching times. We then successfully apply this method to two interesting examples