Risk assessment of landfill disposal sites--State of the art

A risk assessment process can assist in drawing a cost-effective compromise between economic and environmental costs, thereby assuring that the philosophy of 'sustainable development' is adhered to. Nowadays risk analysis is in wide use to effectively manage environmental issues. Risk assessment is also applied to other subjects including health and safety, food, finance, ecology and epidemiology. The literature review of environmental risk assessments in general and risk assessment approaches particularly regarding landfill disposal sites undertaken by the authors, reveals that an integrated risk assessment methodology for landfill gas, leachate or degraded waste does not exist. A range of knowledge gaps is discovered in the literature reviewed to date. From the perspective of landfill leachate, this paper identifies the extent to which various risk analysis aspects are absent in the existing approaches.     

Estimation and inter-comparison of dust aerosols based on MODIS, MISR and AERONET retrievals over Asian desert regions

This study presents detailed analysis of spatiotemporal variations and trend of dust optical properties i.e., Aerosol Optical Depth(AOD) and Angstrom component over Asian desert regions using thirteen years of data(i.e., 2001–2013) retrieved from Aerosol Robotic Network(AERONET), Moderate Resolution Imaging Spectroradiometer(MODIS) and Multi-angle Imaging Spectroradiometer(MISR). These regions include Solar Village, Dunhuang and Dalangzadgad and are considered as origin of desert aerosols in Asia. Mann–Kendall trend test was used to show the trend of AOD. The relationship of AOD with weather parameters and general AOD trend over different wavelengths has also been shown. AOD's trend has been observed significant throughout the year in Solar Village, while in Dunhuang and Dalanzadgad the significant trend has been found only in peak period(March–June).Analysis show high values of AOD and low values of angstrom in Solar Village during peak period. In Chinese desert regions, high values of AOD have been found during peak period and low values in pre-peak period. Significant relationship has been observed between AOD and average temperature in Solar Village and Dalanzadgad whereas rainfall and wind speed showed no significant impact on AOD in all desert regions.     

Engineering of responsive polymer based nano-reactors for facile mass transport and enhanced catalytic degradation of 4-nitrophenol

Silver nanoparticles with average diameter of 10 ± 3 nm were synthesized within the sieves of poly(N-isopropylacrylamide-2-hydroxyethylmethacrylate-acrylic acid)(p(NIPAAm-HEMA-AAc))polymer microgels. Free radial emulsion polymerization was employed for synthesis of p(NIPAAm-HEMA-AAc) polymer microgels. Silver nanoparticles were introduced within the microgels sphere by in situ reduction method. Microgels and hybrid microgels were characterized by Fourier transform infrared spectroscopy, ultra violet-visible spectroscopy,transmission electron microscopy and dynamic light scattering measurements. Catalytic activity of Ag-p(NIPAAm-HEMA-AAc) hybrid microgels was studied using catalytic reduction of 4-nitrophenol(4-NP) as a model reaction in aqueous media. The influence of sodium borohydride(Na BH4) concentration, catalyst dose and 4-NP concentration on catalytic reduction of 4-NP was investigated. A linear relationship was found between catalyst dose and apparent rate constant(kapp). The mechanism of catalysis by hybrid microgels was explored for further development in this area. The deep analysis of catalytic process reveals that the unique combination of NIPAAm, HEMA and AAc does not only stabilize silver nanoparticles in polymer network but it also enhances the mass transport of hydrophilic substrate like 4-NP from outside to inside the polymer network.     

Rewards and employee creative performance: Moderating effects of creative self‐efficacy,reward importance,and locus of control

The effects of extrinsic rewards on creative performance have been controversial, and scholars have called for the examination of the boundary conditions of such effects. Drawing upon expectancy theory, we attend to both reinforcement and self‐determination pathways that reveal the informational and controlling functions of creativity‐related extrinsic rewards. We further identify the individual dispositions that moderate these two pathways. Specifically, we propose that extrinsic rewards for creativity positively predict creative performance only when employees have high creative self‐efficacy and regard such rewards as important. We likewise propose that extrinsic rewards positively affect the intrinsic motivation of employees with an internal locus of control, thus enhancing their creative performance. Results based on a sample of 181 employee–supervisor dyads largely supported these expectations. The current analysis enriches the creativity literature by combining different perspectives in a coherent framework, by demonstrating the positive effects of extrinsic rewards on intrinsic motivation, and by demonstrating that the rewards–creativity relationship varies across employees depending on their individual differences. Copyright © 2014 John Wiley & Sons, Ltd.     

Shortfalls in minerals investments

The international minerals industry continues to have a substantial investment shortfall. The widening exploration and mineral development gaps, not only in the lesser developed countries but also in the developed nations, are sowing the seeds for future mineral supply disruptions and conflicts. Mutuality of interests demands concerted initiatives, individual as well as collective, to reverse the investment trends established by international mineral finance and the multinational corporations in order to pave the way for secure mineral supplies in the future at acceptable prices.     

Variation in vegetation cover and livestock mobility needs in Sahelian West Africa

A new approach was developed to evaluate the implications of the spatiotemporal variability of green vegetation for the dispersion of livestock that is required to access quality forage in semi-arid Africa. Maximum NDVI (Normalized Difference Vegetation Index) at 1 km² resolution was determined for concentric rings (0–31 km radii) around 227 individual sample locations within the study area for 14 dates (between 1 April to 1 November) annually over the 2000–2010 period. A sigmoidal curve was fitted to points within the maximum NDVI × distance radii space to determine the asymptote distance (AD) – the radius at which further dispersion from the sample location does not lead to significant gains in access to green forage. AD was found to: increase with latitude (or increasing aridity); decline as the rainy season proceeds; and show no trend over the 2000–2010 period. These results introduce much-needed empirical data to current debates surrounding the scales of governance to support livestock mobility.     

Economic feasibility of solar-powered reverse osmosis water desalination: a comparative systemic review

Environmental Science and Pollution Research - Due to disparities in the allocation of rainwater and drought, extreme exploitation of groundwater reservoirs has depleted water supplies in many...     

Relative costs of conserving threatened species across taxonomic groups

Bias toward legally protecting and prioritizing charismatic taxonomic groups, such as mammals and birds, and against others, such as insects and plants, is well documented. However, the relative costs of conserving various taxonomic groups and the potential of these costs to interact with existing biases have been much less explored. We analyzed conservation programs across more than 2,000 species in 3 countries to investigate the costs of conserving species within taxonomic groups and how these costs might affect conservation planning. For each data set, we tested for differences in mean annual cost among taxonomic groups. For the data set from the United States, recovery plans differed in duration, so we also tested for differences in total costs among taxonomic groups. Although the costs for individual species varied widely, there were strong international consistencies. For example, mammals cost 8–26 times more on average to conserve than plants and 13–19 times more to conserve than aquatic invertebrates. On average, bird species cost 5–30 times more to conserve than plants and 6–14 times more to conserve than aquatic invertebrates. These cost differences could exacerbate unequal resource allocation among taxonomic groups such that more charismatic groups both receive more attention and require more resources, leading to neglect of other taxonomic groups.