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Measurements of the distribution pattern of several nutrients (ammonia, nitrite, nitrate, and phosphate) and indicators (dissolved oxygen and conductivity) were conducted along the river Coco Solo on the Caribbean coast of Panama. The project investigated the extent to which mangrove forests could act as a vegetative buffer zone between disturbed freshwater sources and coastal water. Upriver freshwater samples were collected in known areas of human disturbance to assess levels of the nutrients near points of origin and exhibited elevated concentrations of nutrients. Samples were taken along the mangrove estuary to study the concentrations of nutrients as they moved through the estuary into the ocean. Expected and observed values were compared to see whether concentration levels of the chemicals exhibited normal dilution patterns. Graphs show that the nutrient levels at the estuary points are significantly lower than expected through normal dilution, indicating the removal of nutrients through another mangrove mediated method. In this way, mangrove forests can act as effective coastal buffers of anthropogenic effects to the ocean environment. Further studies must be done to determine the actual removal mechanisms of nutrients in the mangrove estuarine system.

The increasing demand for organic foods is explained mainly by consumers' concerns about the quality and safety of foods and their perception that organically produced foods are healthier and safer than conventional foods. Based on internationally available concentration data of organic and conventional vegetables (carrots, tomatoes, lettuce and spinach) and potatoes, the paper aims to investigate the scientific validity of nutrition claims as “no vegetable/potato has higher amounts of nutrient X than organic vegetables/potatoes” and “no vegetable/potato has lower amounts of contaminant Y than organic vegetables/potatoes”.

Detailed nutrient and contaminant databases were developed for organic and conventional vegetables separately. Non‐parametric (Mann‐Whitney test) methods were used to detect significant differences between both types of vegetables. A chi‐square test was used to compare the incidence of pesticide residues in organic and conventional vegetables.

From a nutritional and toxicological point of view, organic vegetables and potato in general are not significantly better than conventional vegetables and potatoes. For some nutrients and contaminants organic vegetables and potatoes score significantly better but for others they score significantly worse. Therefore, it becomes difficult to justify general claims indicating a surplus value of organic over conventional vegetables and potatoes. More data from controlled paired studies are needed to reconsider the use of claims for these organic plant foods in the future.

Only a limited number of studies comparing the nutrient and/or contaminant concentration of organic and conventional vegetables are available (“paired studies”). Additionally, the majority of the studies are of moderate or poor quality. The implication is that more of those paired studies are heavily needed. Another limitation of the study is the fact that most pesticide residue data originated from the USA, the EU and Australia.

So far only few studies compared both nutrient and contaminant contents between organic and conventional plant foods. This paper covers therefore an important, not well‐explored research sub area.

This paper aims to investigate a mathematical model with numerical simulation for bacterial growth in the heart valve.

For antibacterial activities and antibodies properties, nanoparticles have been used. As antibiotics are commonly thought to be homogeneously dispersed through the blood, therefore, non-Newtonian fluid of Casson micropolar blood flow in the heart valve for two dimensional with variable properties is used. The heat transfer with induced magnetic field translational attraction under the influence of slip is considered for the resemblance of the heart valve prosthesis. The numeral results have been obtained by using the Chebyshev pseudospectral method.

It is proven that vascular resistance decreases for increasing blood velocity. It is noted that when the magnetic field will be induced from the heart valve prosthesis then it may cause a decrease in vascular resistance. The unbounded molecules and antibiotic concentration that are able to penetrate the bacteria are increased by increasing values of vascular resistance. The bacterial growth density cultivates for upswing values of magnetic permeability and magnetic parameters.

To the best of the authors’ knowledge, this is the first study to investigate a mathematical model with numerical simulation for bacterial growth in the heart valve.

The report is an environmental impact assessment of two conjoining water streams in the lower area of the Wembury catchment where freshwater meets the coast. The assessment was conducted as there were concerns that the streams may be causing exceedances of the Environmental Quality Standards (EQS) due to catchment-based inputs from anthropogenic activities.

Water, sediment samples, and other parameters were collected, measured, and treated to preserve the concentration of nutrients and metals at three sites. A comparison with the neighbouring river Erme was made to determine if the findings were coherent. The report includes recommendations and mitigation strategies needed to improve the environmental quality of the system.

Findings indicate several breaches of EQS: water nitrogen, copper and zinc, and sediment copper. The highest recorded concentrations were mainly at sites one and two, likely from point source inputs from Wembury town and pollution accumulation from upstream land use such as arable and agricultural land. A special precaution must be taken for sediment copper, increasing monitoring to ensure values do not exceed Probable Effects Level (PEL) possibly becoming dangerous for the fauna and flora but also for humans. River Erme showed to also have EQS breaches but to some degree displayed an overall better ecological status. Despite several breaches in the legal limits, Wembury displays an overall good ecological status supporting life above and below water and is therefore an appropriate model for promoting environmental stewardship. It is to be noted that the material of the coursework was further edited after its original submission.

Research over the last 20 years has had a major focus on the ecology of east coast estuaries, including the interaction between coastal seawater and saltmarshes. It is not possible to separate intertidal coastal saltmarshes from the rest of the coastal marine environment as they are involved in a truly interactive system. The significance of this system is attracting increasing attention as the effect of elevated nutrient concentrations on the ecology of the coastal zone has become apparent. It is only when we understand how the various chemical and biological processes influence the flux of nutrients through the estuarine interface between land and sea that any sensible management strategy can be developed.

In this paper properties and dynamical behaviour of a theoretical biological model, the chemoton are discussed. The chemoton features the general, common properties of the unicellular living beings. Since the reaction‐kinetical function of the chemoton is governed by a set of nonlinear differential equations, the study of its dynamical behaviour required computer simulation. This was carried out by using CSMP programs. The results proved that the model is capable of stable functioning, growing and multiplication.

The Bay of Cullera is an example of a multi‐source polluted coastal environment. As a result of the combined discharge from the Júcar River and the sewage from a marine outfall, the Cullera coastal area presents occasionally severe water quality problems. The enhanced knowledge obtained for the most relevant processes affecting the quality of coastal and estuarine waters will lead to the production of suitable strategies and criteria for a sustainable development of these areas. This, together with the generation of a set of scientifically supported alternative policies directed to improve coastal water management, is the main goal of this paper and of the ECOSUD European research project.

The purpose of this review of the literature is to provide readers a foundation of understanding whereby future research can move forward in the quest for global sustainable food production.

This review includes up-to-date information from evidence-based sources on hydroponics. Topics included are advantages, limitations, nutritional quality and sensory quality

Hydroponic growing systems offer the opportunity to at least augment traditional soil-based growing systems in global food production. Some benefits of hydroponic growing systems are limitation of water waste (recirculation), crops grown in controlled environments (control of pests, nutrients and attributes required for optimal plant growth) and ability to manipulate conditions to maximize production in limited space (vertical gardens).

The human population is increasing with a parallel increase in the demand for food; therefore, food production must increase to meet the need.

In spite of the rapid interest and proliferation of information by laypeople, evidence-based research is scant on hydroponics. This article provides a summary of the literature on hydroponics and how it may be used for sustainable food production in arid and urban areas.

Biosolids, the residual solids from wastewater treatment operations and once considered a waste product by the industry, are now becoming increasingly recognised as a multifunctional resource with growing opportunities for marketable use. This shift in attitude towards biosolids management is spurred on by increasing volatility in energy, fertilizer and commodity markets as well as moves by the global community towards mitigating global warming and the effects of climate change. This chapter will provide an overview of current global biosolids practices (paired with a number of Australian examples) as well as discuss potential future uses of biosolids. Additionally, present and future risks and opportunities of biosolids use are highlighted, including potential policy implications.

The association between life and information is discussed. Information is considered to be “a stimulus which expands or amends the World View of the informed”. Using this definition, the standard chain of evolutionary development is reconsidered. It is proposed that information was derived from the environment as a direct result of the evolution of organisms that used other organisms as a food source. Only with the evolution of sexual reproduction did it become necessary for organisms to be aware of others of the same species. It is argued that one of the consequences of the evolution of different sexes is that often, prospective mates had to evolve means of communication, making it possible for animals to expand their World Views by other means. Such reinterpretation of evolutionary thinking has numerous implications for the information scientist. Some of these are discussed.