A landscape of conservation philanthropy for U.S. land trusts

Finding ways to increase financial support is critical to conservation efforts. We used conservation fundraising data, unprecedented in their resolution, to reveal spatial patterns in philanthropic giving to a major land protection organization in the United States. We also quantified the relationship between the amount of effort devoted to fundraising and donations received. Around 40% of the variation in the propensity to give and overall value of gifts was explained by sociodemographic and other predictors. For example, education level had greater predictive capacity than income, political views, and other factors often considered important. Fundraising effort was strongly predictive of the amount donated in an area. Our model estimated a doubling of funds raised with a 5-fold increase of effort. Conservation organizations could use our statistical framework to inform efforts aimed at increasing philanthropic giving by identifying locations with large model residuals. An example application of our framework showed an almost 40% increase (US$200 million) in fundraising revenue for the case-study conservation organization.     

Degradation of Polyethylene Designed for Agricultural Purposes

For many years now, scientific articles have been published on the potential biodegradability of polyethylene. Polyethylene (PE) with peroxidant additives, in the form of agricultural films, is sold by various suppliers as biodegradable mulch. Even though, the photo-chemical and thermal degradation of these products under artificial laboratory conditions is highlighted, several extrapolation on the biodegradation and, moreover, on the neutral environmental impact of PE are made. In this study, three different commercial mulch films have been submitted to standardised biodegradation tests and the results are discussed. The first conclusions are that a very low degree of biodegradation of the commercial PE films is achieved from these tests and that crosslinked PE micro-fragments are found in soil after a very long period of time.     

Numerical integration of chemical ODE problems arising in air pollution models

The numerical treatment of a regional air pollution model (such models are, as a rule, described mathematically by systems of partial differential equations) leads to the solution of very large computational problems. The chemical submodel of an air pollution model is normally the most timeconsuming part of the computational work. The application of appropriate discretization and splitting procedures reduces the chemical submodel to a large number of relatively small ODE systems (one such system per gridpoint). In the process of searching for efficient numerical algorithms for the chemical submodels one can carry out experiments by using only one such ODE system in order to facilitate the work. This approach has been used in connection with a particular chemical scheme, the condensed CBM IV scheme, which is used in several large air pollution models. Six integration algorithms have been tested on a set of typical scenarios (consisting of different starting concentrations and/or of different values of the emissions). The advantages and the disadvantages of the algorithms tested are discussed. The final decision about the most efficient algorithm, among the algorithms tested, should be made after a second series of experiments. The coupling of the chemical process with the transport of air pollution (on, at least, a twodimensional domain) together with the application of highspeed computers has to be studied in the second series of experiments, which will be performed in a subsequent paper.     

Effect of using limestone fines on the chemical shrinkage of pastes and mortars

Environmental Science and Pollution Research - The main aim of this study is to examine the effect of incorporating limestone fine (LF) on chemical shrinkage of pastes and mortars. For this...     

Fluoride Concentration in Drinking Water of Karachi City (Pakistan)

The ground and municipal water supply samples of Karachi city were analyzed for their fluoride contents. The fluoride contents in water samples collected from the subsurface and river sources were found below the WHO recommended value for the general health of the people. However, in some industrial areas the groundwater sample showed higher level of fluoride concentration. Continuous monitoring of water resources and cautious fluoridation is suggested to maintain proper status of fluoride concentration in the drinking water.     

Polybrominated diphenyl ethers (PBDEs) in soils along a rural-urban-rural transect: sources, concentration gradients, and profiles

This study reports concentrations of PBDEs in surface soil samples collected along a 140 km transect across Kuwait to assess the role of urban centers as sources of persistent organic pollutants to the surrounding environment. The ΣPBDE concentrations varied by a factor of ∼250 and ranged from 289 to 80,078 pg g⁻¹ d.w. The concentrations of PBDEs in Kuwait City were significantly higher (p < 0.01) than those collected from sites outside the city supporting the hypothesis that urban centers are sources of PBDEs. The congener profiles were dominated by BDE-209, accounting for 93% of the PBDEs in the soil samples. The concentrations of all congeners (except BDE-209) were highly correlated with percent organic carbon (%OC) (p > 0.05) when the data from Kuwait City was omitted from the analysis. These findings suggest that soil concentrations outside the urban centers were close to equilibrium with the atmosphere.     

Toxic responses in primary rat hepatocytes exposed with occupational dust collected from work environment of bone-based industrial unit

In this in vitro study we investigated the toxic responses in hepatocytes treated with occupational dust to which workers are exposed in bone-based industrial units. The present study investigated the toxicity mechanism of bone-based occupational dust, from a particular industrial unit, on isolated rat hepatocytes. The hepatocytes were isolated by collagenase perfusion method and cell viability was determined by trypan blue exclusion and MTT [3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay treated with occupational dust at 0.1-1.0 mgmL(-1), for 120 min. The cell viability decreased significantly in a concentration-dependent manner. Dust induced significant membrane damage measured by lactate dehydrogenase (LDH) and glutathione (GSH) release in culture media for 30-, 60- and 120 min treatment duration. The toxicity was found to be correlated with the induction of lipid peroxidation (LPO). In addition, nitric oxide (NO), and hydrogen peroxide (H(2)O(2)) generation by occupational dusts were also found to be time- and concentration-dependent. Over all the present study provides initial evidences for the toxic potential of occupational dust generated in bone-based industries and, therefore, the dust exposure to workers in unorganized industrial units should be controlled.     

Mathematical Model for Pollution Source Identification in Rivers

Release of pollution into rivers is required to be handled with special consideration to environmental standards. For this purpose, it is essential to specify the contribution of each pollution source in contamination of water resources. In this study, a mathematical model is proposed for determining locations and concentration release histories of polluting point sources using measured downstream river concentrations via an inverse problem framework. The inverse solution is based on the integral equation obtained from applying the Green's function method on the one-dimensional advection-dispersion contaminant transport equation. Discretization of this integral equation results in a linear, over-determined and ill-posed system of algebraic equations that are solved by using the Tikhonov regularization method. Several examples and some real field data are investigated to illustrate the abilities of the proposed model. Results imply that the proposed method is effective and can identify the pollution sources in rivers with acceptable accuracy.     

Utilization (recycling) of iron and steel industry by-product (GGBS) in concrete: strength and durability properties

Due to exponential growing in urbanization and industrialization, byproducts from industries are becoming an increasing concern for recycling and waste management. Ground granulated blast furnace slag (GGBS) is by-product from the blast-furnaces of iron and steel industries. GGBS is very useful in the design and development of high-quality cement paste/mortar and concrete. This paper covers the properties of GGBS, reaction mechanism, and its effect on strength and durability properties of concrete. Properties covered are sorptivity, microstructure, compressive strength, splitting tensile strength, flexural strength, permeability, sulfate resistance, freezing and thawing resistance, corrosion of concrete.