Characterization of field evolved resistance to transgenic Cry1Fa maize in Spodoptera frugiperda (J. E. Smith)

Transgenic Bt crops expressing Cry and Vip toxins from Bacillus thuringiensis (Bt) have been increasingly planted to manage insect pest damage on agricultural crops. The high adoption of Bt-based insecticidal technologies suggests an increase selection pressure for the evolution of resistance in insect populations. So far, nine insect species have developed field evolved resistance to Bt crops, yet the mechanisms involved in field evolved resistance are unknown. In the present study, the resistance mechanism in field evolved resistance to maize producing Cry1Fa in Spodoptera frugiperda collected in fields from Puerto Rico was characterized. High levels of resistance to Cry1Fa have been observed in S. frugiperda with recessive and autosomal mode inheritance. Binding experiments showed the reduced binding of Cry1Fa toxin to brush border membranes of resistant (456) larvae compared to susceptible (Benzon) larvae. The same binding reduction was observed for Cry1A toxins, but not for Cry1Ca toxin. This reduced binding signifies the modification of a common Cry1Fa-Cry1A toxin binding site. Comparison of receptor protein levels revealed reduced alkaline phosphatase (ALP) levels in resistant compared to susceptible larvae. This reduced expression of ALP phenotype was linked to Cry1Fa resistance in S. frugiperda. In cross-resistance studies using bioassays, reduced susceptibility to Cry1Ab and Cry1Ac toxins was detected and no differences in susceptibility to purified Cry1Bb, Cry1Ca, and Cry1Da toxins or Xentari WG and Dipel ES pesticidal formulations compared to susceptible larvae was detected. The cross-resistance patterns observed in these bioassays are in agreement with data from competition experiments indicating an altered binding site for Cry1A and Cry1Fa toxins in 456 larvae. The only difference detected in fitness cost studies was a significant increase in the larval developmental time in resistant insects, which could result in emergence asynchrony between susceptible and resistant moths. The lack of fitness costs was also supported by stable resistance after 12 generations of rearing in the absence of a selective (transgenic maize) agent. This work is the first study on field level resistance to a Bt crop. Results from this study will help to understand resistance mechanisms responsible for field-level resistance and formulate improved resistance management practices

Subdifferentiability and polyhedrality of the norm

In this paper we give necessary and sufficient conditions for the norm on an infinite dimensional Banach space to be sub differentiable, for various classes of Bananch spaces.Comment: 8 page

Frechet differentiability and quasi-polyhedrality in spaces of operators

Let $X, Y$ be infinite dimensional, Banach spaces. Let $\mathcal{L}(X, Y)$ be the space of bounded operators . Motivated by the fact that smoothness of norm in the higher duals of even order of a Banach space can lead to Frechet differentiability, we exhibit classes of Banach spaces $X, Y$ where very smooth points (i.e., smooth points that remain smooth in the bidual) in the space of compact operators $\mathcal{K}(X, Y)$ are Frechet smooth in $\mathcal{L}(X, Y)$ and hence in $\mathcal{K}(X, Y)$.Comment: 11 page

Order preserving quotient lifting properties

In this paper we formulate order preserving quotient lifting property and the compact lifting property. In the case of affine continuous functions on a Choquet simplex, we show the compact quotient lifting property for the space of affine continuous functions and those vanishing on a metrizable face.Comment: 12 page

Orthogonality for biadjoints of operators

In this paper we study Birkhoff-James Orthogonality for biadjoints of operators. We partly solve the problem, if an operator is orthogonal to the space of operators valued in a subspace, when the is the norm of biadjoint is attained at a point where the value is orthogonal to the subspace?Comment: 8 page

Multilayer nanoparticle arrays for broad spectrum absorption enhancement in thin film solar cells

In this paper, we present a theoretical study on the absorption efficiency enhancement of a thin film amorphous Silicon (a-Si) photovoltaic cell over a broad spectrum of wavelengths using multiple nanoparticle arrays. The light absorption efficiency is enhanced in the lower wavelengths by a nanoparticle array on the surface and in the higher wavelengths by another nanoparticle array embedded in the active region. The efficiency at intermediate wavelengths is enhanced by the simultaneous resonance from both nanoparticle layers. We optimize this design by tuning the radius of particles in both arrays, the period of the array and the distance between the two arrays. The optimization results in a total quantum efficiency of 62.35% for a 300nm thick a-Si substrate.Comment: - Article Published in Optics Express on 7 Apr 2014. Link: http://www.opticsinfobase.org/oe/abstract.cfm?uri=oe-22-103-A80

Prediction of non-centrosymmetric packing for 1,3-disubstituted nitro aromatics. Crystal and molecular structure of 3-hydroxy-6-(3'-nitro)-phenylazopyridine

The crystal and molecular structure of 3-hydroxy-6-(3'-nitro)-phenylazopyridine is reported. The crystals are non-centrosymmetric, Pna21, Z = 4, a = 16.522(3), b = 8.402(2), c = 7.945(1) Å, and the structure refined to an R-value of 0.046 on 1086 non-zero reflections. The molecule exists as the hydroxyazo tautomer and is intermolecularly O-H … N hydrogen bonded in the crystal. The title compound is one of several 1,3-disubstituted benzenes which adopt non-centrosymmetric packing, a necessary prerequisite for nonlinear second harmonic generation. Analysis of nearly 600 nitroaromatic crystal structures retrieved from the Cambridge Structural Database shows that 1,3-disubstitution significantly increases the probability of non-centrosymmetric space group adoption when compared to 1,2 or 1,4-disubstitution. Similar though less pronounced trends are observed for trisubstituted and higher derivatives

Water Demand Forecasting and Comparison of Neural Network Models

Computer Scienc

Non-linear finite element analysis of apple packaging : a thesis presented in partial fulfilment of the requirements for the Master of Technology in Technology and Engineering at Massey University, Palmerston North, New Zealand

The New Zealand Apple and Pears Marketing Board exports apples to over 50 countries, and is one of the New Zealand's largest export earners, netting approximately 500-600 million dollars per year. Competition on the overseas market is very high, and the importers set strict requirements on the condition of the fruit being exported. Therefore, this fruit must be in optimum condition, wherein packaging methods play a vital role to protect the fruit during handling and transit. The packaging is very important to protect the fruit, but little research has been done on its physical and mechanical behaviour. The apple tray is the core object and an integrated part of apple packaging made out of paper pulp, called "Friday Trays", and here is studied for its mechanical and physical behaviour. The project has two phases, testing the material at different environmental conditions and stress analysis of the tray by using "Finite Element Analysis" technique. In the first phase of research, since the "Friday Trays" are handled at different temperatures and humidity levels, the paper pulp material was tested for its mechanical properties such as Stress, Strain, Young's Modulus and Creep at different moisture content levels. The physical and mechanical properties of Paper Pulp materials are affected by moisture content, which is dependent on the humidity of the surrounding environment. The function of the trays is, firstly to transport the apples from conveyor to apple boxes and remove them from the boxes and secondly to act as a cushioning between apples of different layers to prevent damage. In the second phase of the research, the behaviour of the trays was studied in the above conditions by using finite element analysis. The technique was chosen because it can model very complex shapes. The results are displayed in graphical format and can see with maximum stresses or displacements highlighted. The Z pack 70 count trays are investigated at two different conditions of mechanical properties, at 8% moisture content and 20% moisture content. Creation of FEA models are challenging because of the complexity of the problem and vast size of the computer files. The handling situations are successfully generated and used to investigate the relative advantages of packing fully loaded trays, which are then supported at different positions. The tray performed better while being picked up by the ends of the tray and at 8% moisture content. In this situation, the deflection in trays was less when compared to the other situations and the apples less likely to fall off the tray. It was seen that the apples themselves protected the tray from bending during handling, brought about by the apples making contact with each other. Following from this a complete shell model was generated for holding full apples that has contact between neighbouring apples. This used non-linear controls and slidelines. The results show the apples contacting and supporting each other and produce less impact in terms of load on the tray. Analysis of Friday tray is far from complete, greater computer resources will be needed, and has to be checked for the response of lower material properties. Future work should concentrate on developing a dynamic model of a full carton of apples. From the dynamic model, conclusions can be made about the behaviour of trays within the carton