On the status and mechanisms of coastal erosion in Marawila Beach, Sri Lanka

Coastal erosion remains a problem in many developing countries because of a limited understating of erosion mechanisms and management. Sri Lanka is one of the countries that recognized coastal erosion management as a governmental responsibility, in 1984. Nevertheless, erosion mechanisms have not yet been fully understood. We investigate the status and mechanisms of coastal erosion using empirically collected data and various techniques, such as Geographic Information System analysis of satellite images, drone mapping, bathymetric surveys, hindcasting of wind-induced wave climate, questionnaires, and semi-structured interview surveys. We identified wave climate change, reduction in river sand supply, interruptions from previous erosion management measures, and offshore sand mining as potential causes of erosion considering sediment flux and rates of erosion. Erosion of Marawila Beach began during 2005–2010 and has been continuing ever since, due to a lack of integration in the beach and the entire sediment system. It is necessary to identify the long-term, large-scale changes in the sediment system through data collection. This study highlights the importance of an integrated coastal erosion management plan and could facilitate better coastal erosion management in Sri Lanka, as well as in other developing countries

Co-Housing Rodents with Different Coat Colours as a Simple, Non-Invasive Means of Individual Identification:Validating Mixed-Strain Housing for C57BL/6 and DBA/2 Mice

Standard practice typically requires the marking of laboratory mice so that they can be individually identified. However, many of the common methods compromise the welfare of the individuals being marked (as well as requiring time, effort, and/or resources on the part of researchers and technicians). Mixing strains of different colour within a cage would allow them to be readily visually identifiable, negating the need for more invasive marking techniques. Here we assess the impact that mixed strain housing has on the phenotypes of female C57BL/6 (black) and DBA/2 (brown) mice, and on the variability in the data obtained from them. Mice were housed in either mixed strain or single strain pairs for 19 weeks, and their phenotypes then assessed using 23 different behavioural, morphological, haematological and physiological measures widely used in research and/or important for assessing mouse welfare. No negative effects of mixed strain housing could be found on the phenotypes of either strain, including variables relevant to welfare. Differences and similarities between the two strains were almost all as expected from previously published studies, and none were affected by whether mice were housed in mixed- or single-strain pairs. Only one significant main effect of housing type was detected: mixed strain pairs had smaller red blood cell distribution widths, a measure suggesting better health (findings that now need replicating in case they were Type 1 errors resulting from our multiplicity of tests). Furthermore, mixed strain housing did not increase the variation in data obtained from the mice: the standard errors for all variables were essentially identical between the two housing conditions. Mixed strain housing also made animals very easy to distinguish while in the home cage. Female DBA/2 and C57BL/6 mice can thus be housed in mixed strain pairs for identification purposes, with no apparent negative effects on their welfare or the data they generate. This suggests that there is much value in exploring other combinations of strains

Reverse Micelle Synthesis of Co-Al LDHs: Control of Particle Size and Magnetic Properties

Nanoplatelet Co - Al layered double hydroxides (LDHs) {Co 1.8Al1.1(OH)6(DDS)x•yH 2O (DDS = dodecyl sulfate; x ≈ 0.9; y = 2 - 6)} have been prepared using a homogeneous precipitation approach in water pools formed by a water-in-oil reverse microemulsion. The size of the LDH particles is controlled by adjusting the water to surfactant ratio (ω). The particle sizes vary from about 60 × 60 × 13 nm3 to 160 × 160 × 40 nm3 with increasing ω. This contrasts with platelets of Co1.89Al(OH)6(DDS)0.8•4.3H2O prepared by conventional homogeneous precipitation which had dimensions about 2 - 3 μm wide and 0.5 - 1 μm thick. All the Co - Al LDH samples were paramagnetic above 50 K. The molar magnetic susceptibilities of each sample were very similar and they could all be fitted to the Curie - Weiss law with μeff ca. 5.2 μB per Co2+ and θca. 6 K. Below 50 K, we observed a rapid rise in χMT indicative of cooperative ferromagnetic interactions. At very low temperature the LDH nanoplatelets show magnetic behavior which is different to Co 1.8Al1.1(OH)6(DDS)x•yH2O made by conventional homogeneous precipitation. The nanoplatelets show bifurcation in their field-cooled (FC) and zero-field-cooled (ZFC) magnetizations and also a frequency dependence of the in-phase (χ′) and out-of-phase (χ″) ac susceptibilities, which is dependent on the size of the nanoplatelets. © 2010 American Chemical Society

Testing for comparability of human values across countries and time with the third round of the European Social Survey

This study tests the compatibility and comparability of the human values measurements from the third round of the European Social Survey (ESS) to measure the 10 values from Schwartz’ (1992) value theory in 25 countries. Furthermore, it explains the dangers associated with ignoring non-invariance before comparing the values across nations or over time, and specifically describes how invariance may be tested. After initially determining how many values can be identified for each country separately, the comparability of value measurements across countries is assessed using multigroup confirmatory factor analysis (MGCFA). This is necessary to allow later comparisons of values’ correlates and means across countries. Finally, invariance of values over time (2002-2007) is tested. Such invariance allows estimating aggregate value change and comparing it across countries meaningfully. In line with past results, only four to seven values can be identified in each country. Analyses reveal that the ESS value measurements are not suitable for measuring the 10 values; therefore, some adjacent values are unified. Furthermore, a subset of eight countries displays metric invariance for seven values, and metric invariance for 6 values is found for 21 countries. This finding indicates that values in these countries have similar meanings, and their correlates may be compared but not their means. Finally, temporal scalar invariance is evidenced within countries and over time thus allowing longitudinal value change to be studied in all the participating countries