The ability for investigators to visible identify and interpret damage to electrical conductors

The intent of a fire investigations is to correctly interpret the damage in order to identify the cause responsible for the fire and potentially help prevent similar incidents in the future. According to current guidelines of fire scene processing, fire investigators can implement the procedure of arc mapping as a tool to assist in the determination of the fire’s progression and origin at a fire scene. To do this effectively requires the investigator to identify and correctly interpret the damage to electrical conductors as thermal melting (i.e, fire damage) or electrical activity. This study examined the ability of fire investigators to visibly identify and interpret damage to electrical conductors under two different conditions. The first condition requested fire investigators to visibly identify and interpret damage to electrical conductors based on their personal experience alone. In the second condition, fire investigators were asked to visibly identify and interpret damage with the assistance of a technical bulletin prepared by the Federal Bureau of Alcohol, Tobacco and Firearms (ATF) that characterized the visual differences between fire and electrical damage to conductors. The results of this study indicated that regardless of an investigator’s level of experience, the interpretation of the damage could be misconstrued and is dependent on the individual investigator’s perception. Ultimately, the application of the ATF bulletin was found to be a helpful tool for investigators in determining the electrical status of a conductor that had sustained thermal damage but not to any statistical significance. This bulletin could be considered a useful resource in the arc mapping procedure to aid in the determining of a fire’s origin, but should be used in conjunction with other fire investigation techniques

Scaled simulation of the blast effects on structures using lego blocks: a pilot study

Blast effects on structures is an important topic in this modern age for many practising engineers, including structural engineers designing buildings for safety or weapons engineers attempting to destroy enemy infrastructure. Due to the large costs, time demands, space requirements and expertise required, full scale testing is rarely a feasible approach. As such it is important to be able to effectively model the blast effects on structures. Currently, computer modelling techniques are extensively used, however the results of these models are often difficult to verify, whilst requiring experienced expert users to ensure accurate data

On the GRAS status of seaweeds. I. Observations on the association between antibacterial activity of ethanolic extracts and metal levels present in selected seaweeds.

The relationship between antibacterial activity and levels of 24 metals in 19 selected southern African seaweeds was examined. The antibacterial activity of ethanolic extracts of these seaweeds was assessed by agar diffusion against selected Gram positive and Gram negative test bacteria. Metal levels associated with seaweeds were determined using X-ray fluorescence (XRF) analysis. Extracts of the Phaeophyta exhibited the highest level of antibacterial activity, followed by the Rhodophyta and then the Chlorophyta, in decreasing order. Metal levels, however, were highest in the examples studied from the Rhodophyta and then the Phaeophyta and Chlorophyta, in decreasing order. There was no relationship between the observed antibacterial activity of the crude extracts tested and the levels of metals occurring in their tissues. Thus the antimicrobial activity of extracts from the seaweeds tested should also be generally recognised as safe (GRAS)

Carrageenans from Red Seaweeds As Promoters of Growth and Elicitors of Defense Response in Plants

Plants incessantly encounter abiotic and biotic stresses that limit their growth and productivity. However, conversely, plant growth can also be induced by treatments with various abiotic and biotic elicitors. Carrageenans are sulfated linear polysaccharides that represent major cellular constituents of seaweeds belonging to red algae (Rhodophyta). Recent research has unraveled the biological activity of carrageenans and of their oligomeric forms, the oligo carrageenans (OCs), as promoters of plant growth and as elicitors of defense responses against pests and diseases. In this review, we discuss the molecular mechanisms by which carrageenans and OCs mediate plant growth and plant defense responses. Carrageenans and OCs improve plant growth by regulating various metabolic processes such as photosynthesis and ancillary pathways, cell division, purine and pyrimidine synthetic pathways as well as metabolic pathways involved in nitrogen and sulfur assimilation. Carrageenans and OCs also induce plant defense responses against viroids, viruses, bacteria, fungi and insects by modulating the activity of different defense pathways, including salicylate, jasmonate and ethylene signaling pathways. Further studies will likely substantiate the beneficial effects of carrageenans and of OCs on plant growth and plant defense responses and open new avenues for their use in agriculture and horticultural industry

Cultivation of tropical red seaweeds in the BIMP-EAGA region

The Brunei–Indonesia–Malaysia–Philippines East Asia Growth Area (BIMP-EAGA) is located within the Coral Triangle, known to have the world’s richest biodiversity in marine flora and fauna. This region lies within the 10° N and 10° S of the Equator where natural populations of both Kappaphycus and Eucheuma grow luxuriantly and abundantly. It is in this same region where commercial cultivation of Kappaphycus and Eucheuma began in the Philippines around the mid-1960s. Commercial farming of Kappaphycus (which was originally called Eucheuma) was successful in the Philippines from the early 1970s, after which the technology was transferred to Indonesia and Malaysia in the late 1970s. No seaweed cultivation has been reported in Brunei. At present, carrageenophytes are cultivated in sub-tropical to tropical countries circumferentially around the globe within the 10° N and S of the Equator. However, their combined production is still low as compared to Indonesia, the Philippines, and Malaysia. Notably, few improvements in farming techniques have been made since its first introduction. Some of the major improvements were the introduction of deep-water farming using hanging long lines, multiple rafts, and spider webs in the Philippines; the use of short and long ‘loops’, instead of plastic ‘tie-tie’ in Indonesia; and mechanization in harvesting and use of solar “greenhouse” drying in Malaysia. Commercial cultivation of tropical red seaweeds in the BIMP-EAGA region is dominated by Kappaphycus and Eucheuma (carrageenophytes) and Gracilaria (agarophytes) and the area became the major region for the production of carageenophytes and agarophytes globally. In particular, Indonesia is a major center for the production of Gracilaria. There is an increasing demand for other agarophytes / carrageenophytes in the international market such as Gelidium spp., Pterocladia spp., Porphyroglossum sp., and Ptilophora sp. for paper and ethanol production in Indonesia and Malaysia, and Halymenia for phycoerythrin pigments in the Philippines currently pursued in an experimental stage. A summary of the present status, problems, sustainability, and challenges for the cultivation of tropical red seaweeds in the BIMP-EAGA region are discussed in this paper

Análise comparativa dos ficocolóides produzidos por algas carragenófitas usadas industrialmente e algas carragenófitas portuguesas

As Carragenanas (E-407) constituem um dos principais aditivos usados pela indústria alimentar, como agentes gelificantes, emulsionantes, estabilizantes e espessantes. São ingredientes naturais, usados há várias décadas na área alimentar e são considerados como seguros, tendo obtido a classificação GRAS (Generally Recognised As Safe). Neste trabalho foram analisadas a percentagem de peso seco e a composição química (por FTIR e FT-Raman) das carragenanas produzidas pelas carragenófitas (Gigartinales, Rhodophyta) oriundas de diversos países: Kappaphycus alvarezzi (Tanzânia, Indonésia, Filipinas); Kappaphycus striatum (Madagáscar); Eucheuma denticulatum (Tanzânia, Filipinas e Madagáscar); Betaphycus gelatinum (Filipinas); e Sarcothalia crispata (Chile). Para comparação foram também analisadas algas carragenófitas da costa portuguesa (Gigartinales, Rhodophyta): Chondrus crispus, Mastocarpus stellatus; Gigartina pistillata; Chondracanthus teedei var. lusitanicus; Chondracanthus acicularis; Calliblepharis jubata; Gymnogongrus crenulatus; e Ahnfeltiopsis devoniensis. Os principais resultados a reter são: a maior percentagem de peso seco em carragenanas foi obtida a partir das algas carragenófitas Kappaphycus alvarezzi (Filipinas), com 84.4% e Gigartina pistillata (Praia do Norte, Viana do Castelo), com 65.4%. Relativamente à natureza dos ficocolóides produzidos pelas carragenófitas estudadas, as nossas análises espectroscópicas permitiram determinar a presença de um leque diversificado de carragenanas: carragenana iota pura; carragenana kappa quase pura; uma série de carragenanas híbridas kappa-iota, com diferentes rácios iota/kappa; carragenanas kappa-beta, xi-tetha e xi-lambda

Testing the blast response of foam inserts for helmets

Modern era combat helmets have different iterations and configurations to offer greater protection from blunt impact or ballistic penetration to suit the theatre of operation, although there are currently no standards for blast protection. Moreover, incorporation of blast protection into the same constrained mass-volume envelope is extremely challenging as there is very little space for a material to absorb or dissipate the shockwave. Foam padding is fitted in contemporary combat helmet designs for comfort and standoff purposes. Examples were subjected to blastwaves generated from an air-driven shocktube, along with open cell polyurethane foam specimens of varying pores per inch and thicknesses to. Whilst the range of samples tested did not afford any superior blast mitigation behaviour over the foam already present in helmets, they exhibited comparable performance with a lower mass. There also appears to be positive correlation between increased mass and increased impulse transmitted through the foam. The literature suggests that multiple mechanisms of damage for blast induced mild Traumatic Brain Injury (bTBI) can be caused by the helmet itself, therefore additional protection from a blunt or ballistic impact may increase the risk of damage from a blast insult

Woven fabrics in book conservation: An investigation into the properties of aerolinen and aerocotton

Woven fabrics commonly referred to as ‘aerocotton’ and ‘aerolinen’ are frequently used in the conservation of books and manuscripts and are valued for their strength and flexibility. Although textiles have a long history in the production and repair of books, aerocottons and aerolinens are relatively recent materials adopted from early aircraft production. In 2007, the main supplier of these woven fabrics to the UK conservation community ceased production, and new producers started supplying a range of woven fabrics under the labels of ‘aerocotton’ and ‘aerolinen’. Understanding the strength, composition, and longevity of repair materials is central to conservation practice and this investigation tested two linens and two cottons alongside the discontinued cotton to quantify the relative strengths of the fabrics. Each fabric was tested before and after laundering, and in three directions (warp, weft, and bias). The tests conducted measured mass per unit area, thickness, sett, tensile strength, folding endurance, and dimensional change. In tensile strength tests the bias-cut fabrics were weakest but extended the most, whilst those cut in the weft direction were strongest. The cottons lasted longest in terms of folding endurance and the samples cut on the bias were the fastest to break. The dimensional change tests showed that washing affected the linens more than the cottons and that across all fabrics there was a greater amount of shrinkage in the warp direction. It is hoped that these results will provide concrete information to guide conservators in the preparation and use of aerocottons and aerolinens