N=2 SU Quiver with USP Ends or SU Ends with Antisymmetric Matter

We consider the four dimensional scale invariant N=2 SU quiver gauge theories with USp(2N) ends or SU(2N) ends with antisymmetric matter representations. We argue that these theories are realized as six dimensional A_{2N-1} (0,2) theories compactified on spheres with punctures. With this realization, we can study various strongly coupled cusps in moduli space and find the S-dual theories. We find a class of isolated superconformal field theories with only odd dimensional operators $D(\phi)\geq3$ and superconformal field theories with only even dimensional operators $D(\phi)\geq4$.Comment: Minor changes are made; refrences are added; 21 pages, 18 figure

Applied Biotechnology to combat the late blight in potato caused by Phytophthora infestans

Potato is an important crop, grown worldwide. It suffers from many pests and diseases among which late blight, caused by the oomycete Phytophthora infestans, is the worst. The disease is still causing major damage in many potato production areas and control is only possible by applying fungicides frequently. The knowledge on the molecular biology and genetics of the interaction between the plant and the oomycete is developing rapidly. These are relevant fields of study, currently dominated by the discovery of many resistance genes and numerous effector proteins and the analysis of their specific mode of action. These studies may yield essential information needed for the development of durable resistance. The long-term and worldwide effort to breed for resistance so far has had little effect. A novel breeding approach may change this. It is based on cisgenic modification (CM) consisting of marker-free pyramiding of several resistance genes and their spatial and temporal deployment yielding dynamic varieties that contain potato genes only. It is envisioned that this CM approach with potato¿s own genes will not only prove societally acceptable but may also result in simplifications in the legislation on use of the CM approach. Various parties in the potato research arena intend to cooperate in this novel approach in a number of developing countries where potato substantially contributes to food security. The use of resources such as land, water and energy improves when the effect of late blight is markedly reduce

Laser pulse control of a Q-switched Nd:YVO₄ bounce geometry laser using a secondary cavity

Pulsed laser operation is desirable for a wide range of applications such as laser micromachining in industrial manufacturing and laser marking for product identification. In these cases it is beneficial to have flexibility in the parameters of the laser pulse to suit the specific application. This can include the ability to achieve a wide range of pulse repetition rates, with some applications requiring variation of laser pulse rate from high rate (multi-kHz) to low rate or even an off-state in a fast timescale. To generate ultrahigh pulse rates requires Q-switched lasers with ultrahigh gain, but problems can arise if the modulation element is insufficient to prevent laser action or hold-off lasing at low repetition rates. In these cases, lasing output can occur when it is not desired. In this work we present a novel method for pulse control in a high gain bounce amplifier Q-switched system by using a secondary cavity to clamp the gain and allow for clean single pulse operation from very high (800kHz) to very low (e.g.1kHz) repetition rates

Dualisation of the D=9 Matter Coupled Supergravity

We perform the bosonic dualisation of the matter coupled N=1, D=9 supergravity. We derive the Lie superalgebra which parameterizes the coset map whose Cartan form realizes the second-order bosonic field equations. Following the non-linear coset construction we present the first-order formulation of the bosonic field equations as a twisted self-duality condition.Comment: 16 page

Dualisation of the D=7 Heterotic String

The dualisation and the first-order formulation of the D=7 abelian Yang-Mills supergravity which is the low energy effective limit of the D=7 fully Higssed heterotic string is discussed. The non-linear coset formulation of the scalars is enlarged to include the entire bosonic sector by introducing dual fields and by constructing the Lie superalgebra which generates the dualized coset element.Comment: 20 page

Statistical Testing of Optimality Conditions in Multiresponse Simulation-Based Optimization (Replaced by Discussion Paper 2007-45)

This paper derives a novel procedure for testing the Karush-Kuhn-Tucker (KKT) first-order optimality conditions in models with multiple random responses.Such models arise in simulation-based optimization with multivariate outputs.This paper focuses on expensive simulations, which have small sample sizes.The paper estimates the gradients (in the KKT conditions) through low-order polynomials, fitted locally.These polynomials are estimated using Ordinary Least Squares (OLS), which also enables estimation of the variability of the estimated gradients.Using these OLS results, the paper applies the bootstrap (resampling) method to test the KKT conditions.Furthermore, it applies the classic Student t test to check whether the simulation outputs are feasible, and whether any constraints are binding.The paper applies the new procedure to both a synthetic example and an inventory simulation; the empirical results are encouraging.stopping rule;metaheuristics;RSM;design of experiments

Opportunities and constraints of tomato production in Eritrea

Tomato is an important vegetable in Eritrea, grown across the entire country. Yields in Eritrea are comparatively low, due to agronomic, institutional and market constraints. We carried out a survey throughout the country based on a participatory rural appraisal, discussion groups and interviews with staff members of the Ministry of Agriculture. Results showed that farmers preferred varieties with a prolonged harvesting period and a long storage life unless other varieties are better yielding and can immediately be marketed. However, their knowledge on varieties is limited while maintaining their own seeds. Seedlings are established in nurseries and subsequently transplanted once they have reached a height of 10 to 15 cm. Spacing, staking, pruning and irrigation are important aspects of proper crop management. Flower abortion is common in some areas and the crop is affected by several diseases and pests. The harvesting takes place over a prolonged period and timing of harvest of individual fruits is based on skin colour. There are significant price differences based on size grade. Seasonality of the crop causes problems with marketing and price fluctuation. It is recommended to improve the farmer’s knowledge on variety characteristics, to improve the seed systems and train the farmers in improved crop managemen

Capital Controls and Foreign Investor Subsidies Implicit in South Africa's Dual Exchange Rate System

Both in theory and practice, capital controls and dual exchange rate systems can be part of a country's optimal tax policy. We first show how a dual exchange rate system can be interpreted as a tax (or subsidy) on international capital income. We show that a dual exchange rate system, with separate commercial and financial exchange rates, drives a wedge between the domestic and foreign returns on comparable assets. As a borrower, the government itself is a direct beneficiary. Secondly, based on data from South Africa, we present empirical evidence of this revenue implicit in a dual exchange rate system; a revenue that amounted to as much as 0.1 percent of GDP for the South African government. However, this paper also shows that both the capital controls and the dual exchange rate system in South Africa gave rise to many perverse unanticipated e¤ects. The latter may render capital controls and dual exchange rate systems unattractive in the end and, thereby, provides a rationale for the recent trend in exchange rate liberalization and unification.Dual exchange rate systems;capital controls;emerging markets;financial repression;optimal tax policy

The Six Dimensional Self-Dual Tensor

The equations of motion for a self-interacting self-dual tensor in six dimensions are extracted from the equations describing the M-theory five-brane. These equations are presented in a self-contained, six-dimensional Lorentz-covariant form. In particular, it is shown that the field-strength tensor satisfies a non-linear generalised self-duality constraint. The self-duality equation is rewritten in five-dimensional notation and shown to be identical to the corresponding equation in the non-covariant formalism.Comment: 8 pages, late

Universality of Sypersymmetric Attractors

The macroscopic entropy-area formula for supersymmetric black holes in N=2,4,8 theories is found to be universal: in d=4 it is always given by the square of the largest of the central charges extremized in the moduli space. The proof of universality is based on the fact that the doubling of unbroken supersymmetry near the black hole horizon requires that all central charges other than Z=M vanish at the attractor point for N=4,8. The ADM mass at the extremum can be computed in terms of duality symmetric quartic invariants which are moduli independent. The extension of these results for d=5, N=1,2,4 is also reported. A duality symmetric expression for the energy of the ground state with spontaneous breaking of supersymmetry is provided by the power 1/2 (2/3) of the black hole area of the horizon in d=4 (d=5). It is suggested that the universal duality symmetric formula for the energy of the ground state in supersymmetric gravity is given by the modulus of the maximal central charge at the attractor point in any supersymmetric theory in any dimension.Comment: few misprints removed, version to appear in Phys. Rev. 20 pages, 1 figur