Water Neutral: Reducing and Offsetting the Impacts of Water Footprints

During the past few years the water footprint has started to receive recognition as a useful indicator of water use, within both governments (UNESCO, 2006) and non-governmental organizations (Zygmunt, 2007; WWF, 2008), as well as within businesses (WBCSD, 2006; JPMorgan, 2008) and media (The Independent, 2008; The Economist, 2008; Discover Magazine, 2008). The increased interest in the water-footprint concept has prompted the question about what consumers and businesses can do to reduce their water footprint. Several instruments have been proposed, including a water label for water-intensive products, an international water-pricing protocol, an international business agreement on water-footprint accounting, and a Kyoto-protocol-like agreement on tradable water-footprint permits (Hoekstra, 2006; Verkerk et al., 2008). Another concept that has been proposed is that of 'water neutrality'. The idea behind the concept is to see whether humans can somehow neutralise or offset their 'water footprint'. The question is very general and interesting from the point of view of both individual consumers and larger communities, but also from the perspective of governments and companies. The aim of this report is to critically discuss the water-neutral concept. It first discusses the water-footprint concept, because water neutrality is all about reducing and offsetting the impacts of water footprints (Figure 1.1). Subsequently, the report elaborates the idea of water neutrality. After a generic discussion of the concept, it is discussed what water neutrality means for a product, an individual consumer or a business. Finally, the concept is critically analysed in terms of its strengths and weaknesses

Lasercooled RaF as a promising candidate to measure molecular parity violation

The parameter $W_\mathrm{a}$, which characterizes nuclear spin-dependent parity violation effects within the effective molecular spin-rotational Hamiltonian, was computed for the electronic ground state of radium fluoride (RaF) and found to be one of the largest absolute values predicted so far. These calculations were performed with the complex generalised Hartree-Fock method within a two-component (quasi-relativistic) zeroth-order regular approximation framework. Peculiarities of the molecular electronic structure of RaF lead to highly diagonal Franck-Condon matrices between vibrational states of the electronic ground and first excited states, which renders the molecule in principle suitable for direct laser cooling. As a trapped gas of cold molecules offers a superior coherence time, RaF can be considered a promising candidate for high-precision spectroscopic experiments aimed at the search of molecular parity-violation effects.Comment: 4.5 pages, 1 figure, 2 tables. Supplementary material can be requested from the authors. Minor changes to version

Simple technique for two-photon absorption measurements in polymeric waveguide channels

A simple technique for two-photon absorption measurements by pulse shape deformation in channel optical waveguides is described. Measurements on a ps time scale are performed. Results are in good agreement with literature value

Effects of lattice variations on confinement in photonic crystal microcavity using green tensor method

Electric field distribution in and around the 2D PC cavity was calculated for different lattice parameters using the Dyson formulation of the Green tensor. The results demonstrate the sensitive effects of structural variation of the photonic crystal on the effectiveness of field confinement in the cavity

Light Turning Mirrors in SiON Optical Waveguides for Hybrid Integration with CMOS Photo-detectors

A new method is proposed for hybrid integration of SiON optical waveguides and standard CMOS photo-detectors based on anisotropic etching of 45° facets in a Si substrate. After removal of anisotropically etched Si structures in cladding SiO2, the fabricated total-internal-reflection mirrors can direct the output of the waveguides to photo-detectors placed on top of the chip. The metal-free fabrication process, designed to create these mirrors, is convenient for batch production. Fourier optics based simulations predict that the reflection efficiency of the mirrors is 68.5 %. The far field pattern obtained from the fabricated device is similar to the simulated one

Association between consumption of black tea and iron status in adult Africans in the North West Province: The THUSA study

The association between black tea consumption and iron status was investigated in a sample of African adults participating in the cross-sectional THUSA (Transition and Health during Urbanization of South Africans) study in the North West Province, South Africa. Data were analysed from 1605 apparently healthy adults aged 15-65 years by demographic and FFQ, anthropometric measurements and biochemical analyses. The main outcome measures were Hb and serum ferritin concentrations. No associations were seen between black tea consumption and concentrations of serum ferritin (men P=0.059; women P=0.49) or Hb (men P=0.33; women P=0.49). Logistic regression showed that tea consumption did not significantly increase risk for iron deficiency (men: OR 1.36; 95 % CI 0.99, 1.87; women: OR 0.98; 95 % CI 0.84, 1.13) nor for iron deficiency anaemia (men: OR 1.28: 95 % Cl 0.84, 1.96; women: OR 0.93; 95 % Cl 0.78, 1.11). Prevalence of iron deficiency and iron deficiency anaemia was especially high in women: 21.6 and 14.6 %, respectively. However, the likelihood of iron deficiency and iron deficiency anaemia was not significantly explained by tea consumption in sub-populations which were assumed to be at risk for iron deficiency. Regression of serum ferritin levels on tea consumption in women : 40 years, adults with a daily iron intak

Optical response of highly granular YBaCuO films prepared by non-vacuum aerosol deposition

Highly granular YBaCuO films on SrTiO3 substrates with Tc,o~90K and Jc > 104 A/cm2 were prepared by non-vacuum aerosol deposition. The optical response for these films was investigated on a 10 × 10 μm2 microbridge. Besides a bolometric response around the transition temperature, a sharp response peak was observed at low temperature and high bias current using a He-Ne laser (0.63 μm wavelength) illumination. This response was caused by a junction behaviour due to the presence of many boundary-type weak links in our microbridge

Time domain beam propagation method for the simulation of temporal solitons in periodic media

A time domain beam propagation method for the simulation of optical pulses propagating through Kerr-nonlinear structures is presented. The method is verified by simulation of the known solitary wave solutions in nonlinear periodic medi