Ignition Risks of Biomass Dust on Hot Surfaces

Combustible biomass dusts are formed at various handling stages, and accumulations of these dusts can occur on hot surfaces of electrical and mechanical devices and can pose fire risks. This study evaluates the ignition characteristics of dust from two types of biomass commonly used in the U.K. power stations: herbaceous miscanthus and woody pine. The ignition risks of the individual biomass and their blends in two different weight ratios, 90 wt % pine to 10 wt % miscanthus and 50 wt % pine to 50 wt % miscanthus, were investigated. Biomass–biomass blends represent the power plant scenario where a number of biomass are fired under daily operation, and thus, dust sedimentation could consist of material blends. The influence of washing pretreatment (particularly to remove catalytic potassium) on the ignition behavior of these dusts was investigated. Fuel characterization via proximate and ultimate analyses was performed on all fuels and combustion characteristics via thermogravimetric analysis (TGA). The risk of self-ignition propensity of both untreated and washed biomass was ranked graphically using the activation energy (Ea) for combustion and the temperature of maximum weight loss (TMWL) determined from the derivative TGA (DTG) curve. It was found that the TMWL and Ea of washed biomass were higher than those of the untreated biomass, implying a lower self-ignition risk. Similar analyses were performed on untreated and washed blends, and comparable results were observed. The ignition characteristics were studied following the British Standard test methods for determining the minimum ignition temperature of a 5 mm dust layer on a heated surface. It was found that the washed individual biomass and their blends revealed slightly higher dust ignition temperatures than their respective untreated counterparts, a 20 and 10 °C difference for individual biomass and blends, respectively. The effect of washing on the ignition delay time was more obvious for pine than for miscanthus, but the time difference between the untreated and washed biomass never exceeded 4 min for all biomass and blends. The biomass pretreatment method of washing did change the combustion and self-ignition characteristics of biomass dust, and there was evidence of potassium being leached from the fuels upon washing (particularly miscanthus). This is considered the main reason for the increase in the minimum ignition temperature. While the washed biomass is found to have a lower ignition risk, it should be noted that the result (validated for up to 5 mm thickness) is not significant enough to influence plant operations for the ignition risk from thin dust layers according to the National Fire Protection Association (NFPA) standard

A review of agro-potential waste as a constituent in railway sleepers

Historically, concrete was used exclusively for building construction. Concrete has recently found application in the railway business, notably in the construction of concrete railway sleepers. Concrete is made up of three primary ingredients: fine aggregates, coarse aggregates, and cement. To enhance the qualities of concrete, research was conducted on the possibility of substituting wastes from other industries for the ingredients of concrete. With agriculture being one of Malaysia's main industries, ranking third in terms of national economic activity, it demonstrated the potential for using agricultural wastes as ingredients of concrete manufacturing (fine aggregate, coarse aggregate, and cement). While the characteristics of agricultural waste-derived concrete have improved, research on their use as concrete railway sleepers remains uncommon. As such, this article will examine the feasibility of incorporating agricultural waste into concrete for the manufacturing of concrete railway sleepers

Increased entropy of signal transduction in the cancer metastasis phenotype

Studies into the statistical properties of biological networks have led to important biological insights, such as the presence of hubs and hierarchical modularity. There is also a growing interest in studying the statistical properties of networks in the context of cancer genomics. However, relatively little is known as to what network features differ between the cancer and normal cell physiologies, or between different cancer cell phenotypes. Based on the observation that frequent genomic alterations underlie a more aggressive cancer phenotype, we asked if such an effect could be detectable as an increase in the randomness of local gene expression patterns. Using a breast cancer gene expression data set and a model network of protein interactions we derive constrained weighted networks defined by a stochastic information flux matrix reflecting expression correlations between interacting proteins. Based on this stochastic matrix we propose and compute an entropy measure that quantifies the degree of randomness in the local pattern of information flux around single genes. By comparing the local entropies in the non-metastatic versus metastatic breast cancer networks, we here show that breast cancers that metastasize are characterised by a small yet significant increase in the degree of randomness of local expression patterns. We validate this result in three additional breast cancer expression data sets and demonstrate that local entropy better characterises the metastatic phenotype than other non-entropy based measures. We show that increases in entropy can be used to identify genes and signalling pathways implicated in breast cancer metastasis. Further exploration of such integrated cancer expression and protein interaction networks will therefore be a fruitful endeavour.Comment: 5 figures, 2 Supplementary Figures and Table

Specific, sensitive and rapid detection of human plasmodium knowlesi infection by loop-mediated isothermal amplification (LAMP) in blood samples

<p>Abstract</p> <p>Background</p> <p>The emergence of <it>Plasmodium knowlesi </it>in humans, which is in many cases misdiagnosed by microscopy as <it>Plasmodium malariae </it>due to the morphological similarity has contributed to the needs of detection and differentiation of malaria parasites. At present, nested PCR targeted on <it>Plasmodium </it>ssrRNA genes has been described as the most sensitive and specific method for Plasmodium detection. However, this method is costly and requires trained personnel for its implementation. Loop-mediated isothermal amplification (LAMP), a novel nucleic acid amplification method was developed for the clinical detection of <it>P. knowlesi</it>. The sensitivity and specificity of LAMP was evaluated in comparison to the results obtained via microscopic examination and nested PCR.</p> <p>Methods</p> <p>LAMP assay was developed based on <it>P. knowlesi </it>genetic material targeting the apical membrane antigen-1 (AMA-1) gene. The method uses six primers that recognize eight regions of the target DNA and it amplifies DNA within an hour under isothermal conditions (65°C) in a water-bath.</p> <p>Results</p> <p>LAMP is highly sensitive with the detection limit as low as ten copies for AMA-1. LAMP detected malaria parasites in all confirm cases (n = 13) of <it>P. knowlesi </it>infection (sensitivity, 100%) and none of the negative samples (specificity, 100%) within an hour. LAMP demonstrated higher sensitivity compared to nested PCR by successfully detecting a sample with very low parasitaemia (< 0.01%).</p> <p>Conclusion</p> <p>With continuous efforts in the optimization of this assay, LAMP may provide a simple and reliable test for detecting <it>P. knowlesi </it>malaria parasites in areas where malaria is prevalent.</p

Technologies for removing pharmaceuticals and personal care products (PPCPs) from aqueous solutions: Recent advances, performances, challenges and recommendations for improvements

In recent years, the removal of pharmaceutical and personal care products (PPCPs) from aqueous solutions has been gaining a lot of attention from researchers throughout the world. This is particularly due to the concern about their potential hazards and toxicities, as they are classified as emerging contaminants. Thus, there is an increasing need to investigate removal technologies for PPCPs at a deeper and more holistic level. This review aims to provide the latest developments in removal technologies for PPCPs. It first succinctly describes the types, characteristics, and hazards of PPCPs on the environment and human health. It then comprehensively covers a wide range of technologies for removing PPCPs from aqueous solutions, comprising the adsorption process (using carbon-based adsorbents, plant biomasses, clay and clay minerals, silica-based adsorbents, zeolite-based adsorbents, polymers and resins, and hybrid adsorbents), advanced oxidation processes (AOPs) (photocatalysis, Fenton or photo-Fenton or electro-Fenton, ozonation, ultrasonication, electrochemical oxidation, persulfate oxidation), membrane separation processes (ultrafiltration, nanofiltration, reverse osmosis), biodegradation processes (bacteria, fungi, and algae), and hybrid treatment (adsorption-AOP, AOP-membrane, membrane-biodegradation, and others). According to the specific experimental conditions, the reported removal efficiencies for adsorption, AOPs, membrane processes, biodegradation processes and hybrid treatment were 40–100%, 40–100%, 3–100%, 14–100% and 5–100%, respectively. This review paper also highlights the challenges in this field of research, particularly incomplete removal of certain PPCPs, high costs of some treatment technologies and generally insufficient understanding on the removal kinetics and mechanisms of PPCPs. This review offers recommendations for future works to further advance the technical performances to eventually realize the wider application of these technologies at the industrial scale

Regulation of High-Temperature Stress Response by Small RNAs

Temperature extremes constitute one of the most common environmental stresses that adversely affect the growth and development of plants. Transcriptional regulation of temperature stress responses, particularly involving protein-coding gene networks, has been intensively studied in recent years. High-throughput sequencing technologies enabled the detection of a great number of small RNAs that have been found to change during and following temperature stress. The precise molecular action of some of these has been elucidated in detail. In the present chapter, we summarize the current understanding of small RNA-mediated modulation of high- temperature stress-regulatory pathways including basal stress responses, acclimation, and thermo-memory. We gather evidence that suggests that small RNA network changes, involving multiple upregulated and downregulated small RNAs, balance the trade-off between growth/development and stress responses, in order to ensure successful adaptation. We highlight specific characteristics of small RNA-based tem- perature stress regulation in crop plants. Finally, we explore the perspectives of the use of small RNAs in breeding to improve stress tolerance, which may be relevant for agriculture in the near future