Part 1: Guidance on the design of sampling programmes and sampling techniques EN ISO 5667-1:2006

This part of ISO 5667 sets out the general principles for, and provides guidance on, the design of sampling programmes and sampling techniques for all aspects of sampling of water (including waste waters, sludges, effluents and bottom deposits). It does not include detailed instructions for specific sampling situations, which are covered in the various other parts of ISO 5667. Also, it does not include microbiological sampling, which is covered in ISO 19458 [23].

Section 2.7 Determination of ammonium: distillation and titration method

Scope

This International Standard specifies a distillation and titration method for the determination of ammonium in raw, potable and waste water.An ammonium nitrogen content of up to 10 mg in the test portion may be determined. Using a 10 ml test portion, this corresponds to a sample concentration of up to A’N P = 1 000 mg/l.

Water quality Part 2: Physical, chemical and biochemical methods BS 6068-2.34:1988

The chemical oxygen demand, COD, of water as determined by this dichromate method can be considered as an approximate measure of the theoretical oxygen demand, i.e. the amount of oxygen consumed in total chemical oxidation of the organic constituents to inorganic end products (see also clause 9). The degree to which the test results approach the theoretical value depends primarily on how complete the oxidation is. A great number of organic compounds are oxidized to an extent of between 90 % and 100 %, and for waters where these compounds predominate, such as municipal effluents, the COD value is a realistic measure of the theoretical oxygen demand. For other waters which contain large quantities of certain substances that are difficult to oxidize under the conditions of the test (see clause 9), the COD value is a poor measure of the theoretical oxygen demand. This may be the case for some industrial effluents. The significance of a COD value thus depends on the composition of the water studied. This should be borne in mind when judging results obtained by the method described in this Section of BS 6068.

Tumor Self-Seeding by Circulating Cancer Cells

Summary

Cancer cells that leave the primary tumor can seed metastases in distant organs, and it is thought that this is a unidirectional process. Here we show that circulating tumor cells (CTCs) can also colonize their tumors of origin, in a process that we call “tumor self-seeding.” Self-seeding of breast cancer, colon cancer, and melanoma tumors in mice is preferentially mediated by aggressive CTCs, including those with bone, lung, or brain-metastatic tropism. We find that the tumor-derived cytokines IL-6 and IL-8 act as CTC attractants whereas MMP1/collagenase-1 and the actin cytoskeleton component fascin-1 are mediators of CTC infiltration into mammary tumors. We show that self-seeding can accelerate tumor growth, angiogenesis, and stromal recruitment through seed-derived factors including the chemokine CXCL1. Tumor self-seeding could explain the relationships between anaplasia, tumor size, vascularity and prognosis, and local recurrence seeded by disseminated cells following ostensibly complete tumor excision.

Oil spill identification Waterborne petroleum and petroleum products PD CEN/TR 15522-1:2006

Where an oil pollution incident has occurred, samples should be collected from both the spill and, wherever possible, the potential source of the pollutant, e.g. ship, shore tank, pipeline or road vehicle, in order to assist in the identification or confirmation of the source of the spill. The aim of this document is to give guidance on the best current practice for taking such samples. This document does not contain details relating to all types of spill situation, but should only be regarded as general guidelines. However, by following these guidelines it should be possible to collect and provide legally valid samples that can be used in the process of identifying or confirming the source of the spill. The issues addressed only cover the mechanics of sample collection. The command and control that may be put in place during incident response, the authorities who may request sample collection and the individuals who have the authority to collect samples, will vary from country to country and as a consequence these issues are not addressed

The Environmental Impact of Shrimp Aquaculture and the Coastal Pollution in Mexico

The moderated, but continual development of the shrimp aquaculture in Mexico, in conjunction with municipal and agriculture effluents, in the last decade has created the first symptoms of negative environmental impacts, due mainly to the discharge of nutrients and organic matter into adjacent coastal waters. Similarly, the increasing impairment of coastal water quality resulting from the discharge of domestic, agricultural and industrial wastes into coastal waters has affected the aquaculture profitability in certain areas. The cumulative impact of the main anthropogenic sources of nutrients in the Mexican coastal states was estimated in 190 088 ton N yr-1 and 51 831 ton P yr -1. The input from shrimp aquaculture is only 1.5% and 0.9% of the main sources of nitrogen and phosphorus. This last input, though small, is related to local and adverse effects on coastal ecosystems. The introduction of management measures to mitigate the adverse environmental impacts of shrimp aquaculture development has now become necessary and urgent

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X-FEM analyses of a thin-walled composite shell structure with a delamination

The extended finite element method is applied to stress analyses of composite laminates modeled by shell elements. In the proposed method, a thin-walled structure containing an interface is modeled by shell elements, and the nodes on the interface are enriched in order to model the delamination. The X-FEM code for thin-walled structures based on the proposed method is developed and is applied to buckling analyses of Carbon Fiber-Reinforced Plastic laminate with delaminations. The proposed X-FEM for shell elements was shown to provide appropriate results, which agree well with those obtained by the X-FEM for solid elements and conventional FEM analyses.

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