Life cycle assessment of magnetic and electronic ballast for 36-W fluorescent lamp

Background, aim, and scope   

Ballast is a device in a fluorescent lamp that supports the production of light. In this study, the environmental impacts of two types of Malaysian ballast, magnetic ballast and electronic ballast, were identified and compared using the life cycle assessment approach through the ISO 14040 (2005) series.     

Differentially expressed genes in embryonic cardiac tissues of mice lacking <Emphasis Type="Italic">Folr1</Emphasis>gene activity

Background  

Heart anomalies are the most frequently observed among all human congenital defects. As with the situation for neural tube defects (NTDs), it has been demonstrated that women who use multivitamins containing folic acid peri-conceptionally have a reduced risk for delivering offspring with conotruncal heart defects [1–3]. Cellular folate transport is mediated by a receptor or binding protein and by an anionic transporter protein system. Defective function of the Folr1 (also known as Folbp1; homologue of human FRα) gene in mice results in inadequate transport, accumulation, or metabolism of folate during cardiovascular morphogenesis.     

Characterization of oxylipins and dioxygenase genes in the asexual fungus Aspergillus niger

Background  

Aspergillus niger is an ascomycetous fungus that is known to reproduce through asexual spores, only. Interestingly, recent genome analysis of A. niger has revealed the presence of a full complement of functional genes related to sexual reproduction [1]. An example of such genes are the dioxygenase genes which in Aspergillus nidulans, have been shown to be connected to oxylipin production and regulation of both sexual and asexual sporulation [2–4]. Nevertheless, the presence of sex related genes alone does not confirm sexual sporulation in A. niger.     

A preliminary LCA case study: comparison of different pathways to produce purified terephthalic acid suitable for synthesis of 100 % bio-based PET

Purpose

This study provides a preliminary comparison of the environmental burdens of three different pathways for production of bio-based purified terephthalic acid (PTA), suitable for the production of 100 % bio-based poly(ethylene terephthalate), PET. These pathways are through (1) muconic acid originating in wheat stover; (2) isobutanol originating in corn; and (3) benzene, toluene, and xylene (BTX) originating in poplar. The goal is to point out what areas of these processes are the largest environmental contributors and hence are the most critical for development of accurate primary data, as well as to indicate which of these pathways looks most promising, from an environmental viewpoint, for production of 100 % bio-based PET.

Methods

Because much of the needed life cycle information to produce PTA is currently not available, inventory data for each scenario for the production of PTA were estimated based on the chemistry involved. In the impact analysis stage, the inventory data were classified and characterized with a focus on several environmental midpoint categories. SimaPro 7.3.3 software was used as the main computational software and Impact 2002+ v2.1 was used as the life cycle impact assessment methodology in this attributional life cycle assessment.

Results and discussion

Valuable preliminary environmental impact data including identification of critical steps in the process were obtained. The global warming value of PET synthesized through the muconic acid scenario was 1.6 times larger than that of the scenario of PET synthesized through BTX even after a limited Monte Carlo simulation of 1,000 runs.

Conclusions

Among the three scenarios for producing PET, PET synthesized through BTX looked the most promising to pursue for production of bio-based PET with lower environmental burdens. This work also indicated that the first production steps of producing PET through any of the evaluated scenarios (from biomass to the first intermediate) are responsible for the largest environmental burden and should be further characterized since they were the dominant processes in many impact categories.     

Implications of considering metal bioavailability in estimates of freshwater ecotoxicity: examination of two case studies

Purpose  

Previous methods of estimating characterization factors (CFs) of metals in life cycle impact assessment (LCIA) models were based on multimedia fate, exposure, and effect models originally developed to address the potential impacts of organic chemicals. When applied to metals, the models neglect the influence of ambient chemistry on metal speciation, bioavailability and toxicity. Gandhi et al. (2010) presented a new method of calculating CFs for freshwater ecotoxicity that addresses these metal-specific issues. In this paper, we compared and assessed the consequences of using the new method versus currently available LCIA models for calculating freshwater ecotoxicity, as applied to two case studies previously examined by Gloria et al. (2006): (1) the production of copper (Cu) pipe and (2) a zinc (Zn) gutter system.     

Cationic hydrous thorium dioxide colloids - a useful tool for staining negatively charged surface matrices of bacteria for use in energy-filtered transmission electron microscopy

Background  

Synthesis of cationic hydrous thorium dioxide colloids (ca. 1.0 to 1.7 nm) has been originally described by Müller [22] and Groot [11] and these have been used by Groot to stain acidic glucosaminoglycans for ultrastructure research of different tissues by conventional transmission electron microscopy.     

CRK9 contributes to regulation of mitosis and cytokinesis in the procyclic form of Trypanosoma brucei

Background  

The Trypanosoma brucei cell cycle is regulated by combinations of cyclin/CRKs (cdc2 related kinases). Recently, two additional cyclins (CYC10, CYC11) and six new CRK (CRK7-12) homologues were identified in the T. brucei genome database [1,2].     

Envelope structure of Synechococcus sp. WH8113, a nonflagellated swimming cyanobacterium

Background  

Many bacteria swim by rotating helical flagellar filaments [1]. Waterbury et al. [15] discovered an exception, strains of the cyanobacterium Synechococcus that swim without flagella or visible changes in shape. Other species of cyanobacteria glide on surfaces [2,7]. The hypothesis that Synechococcus might swim using traveling surface waves [6,13] prompted this investigation.     

Comparative genomics of lactic acid bacteria reveals a niche-specific gene set

Background  

The recently sequenced genome of Lactobacillus helveticus DPC4571 [1] revealed a dairy organism with significant homology (75% of genes are homologous) to a probiotic bacteria Lb. acidophilus NCFM [2]. This led us to hypothesise that a group of genes could be determined which could define an organism's niche.     

Diversifying selection and functional analysis of interleukin-4 suggests antagonism-driven evolution at receptor-binding interfaces

Background  

Interleukin-4 (IL4) is a secreted immunoregulatory cytokine critically involved in host protection from parasitic helminths [1]. Reasoning that helminths may have evolved mechanisms to antagonize IL4 to maximize their dispersal, we explored mammalian IL4 evolution.     

Life cycle assessment of Australian sugarcane products with a focus on cane processing

Purpose  

This work generates attributional life cycle assessment (LCA) results for products produced from Australian sugarcane—raw sugar, molasses, electricity (from bagasse combustion), and ethanol (from molasses). It focuses on cane processing in sugar mills and is a companion to the work presented in (Renouf et al. 2010), where the focus is on cane growing. This work also examines the preferred approach for assigning impacts to the multiple products from cane processing, and the influence that variability in cane growing has on the results.     

Modeling the effects of a Staphylococcal Enterotoxin B (SEB) on the apoptosis pathway

Background  

The lack of detailed understanding of the mechanism of action of many biowarfare agents poses an immediate challenge to biodefense efforts. Many potential bioweapons have been shown to affect the cellular pathways controlling apoptosis [1–4]. For example, pathogen-produced exotoxins such as Staphylococcal Enterotoxin B (SEB) and Anthrax Lethal Factor (LF) have been shown to disrupt the Fas-mediated apoptotic pathway [2, 4]. To evaluate how these agents affect these pathways it is first necessary to understand the dynamics of a normally functioning apoptosis network. This can then serve as a baseline against which a pathogen perturbed system can be compared. Such comparisons can expose both the proteins most susceptible to alteration by the agent as well as the most critical reaction rates to better instill control on a biological network.     

Weighted bootstrapping: a correction method for assessing the robustness of phylogenetic trees

Background  

Non-parametric bootstrapping is a widely-used statistical procedure for assessing confidence of model parameters based on the empirical distribution of the observed data [1] and, as such, it has become a common method for assessing tree confidence in phylogenetics [2]. Traditional non-parametric bootstrapping does not weigh each tree inferred from resampled (i.e., pseudo-replicated) sequences. Hence, the quality of these trees is not taken into account when computing bootstrap scores associated with the clades of the original phylogeny. As a consequence, traditionally, the trees with different bootstrap support or those providing a different fit to the corresponding pseudo-replicated sequences (the fit quality can be expressed through the LS, ML or parsimony score) contribute in the same way to the computation of the bootstrap support of the original phylogeny.     

Life cycle inventory processes of the ArcelorMittal Poland (AMP) S.A. in Kraków,Poland—basic oxygen furnace steel production

Purpose  

The goal of this paper is to describe the life cycle inventory (LCI) approach to steel produced by ArcelorMittal’s Basic Oxygen Furnace (AMBOF) in Kraków, Poland. The present LCI is representative for the reference year 2005 by application of PN-EN ISO 14040:2009 (PN-EN ISO 2009). The system boundaries were labeled as gate-to-gate (covering a full chain process of steel production). The background input and output data from the basic oxygen furnace (BOF) steelmaking process has been inventoried as follows: pig iron, scrap, slag forming materials (CaO), ferroalloys, Al, carbon and graphite carburizer (material for carburization of steel), isolating powder, consumption of energy and fuels including natural gas, blast furnace gas and coke oven gas, electric energy, steam, air, oxygen, industrial water and heat, emission of air pollutants, waste, internal transport and land use.     

A response to information criterion-based clustering with order-restricted candidate profiles in short time-course microarray experiments

Background  

For gene expression data obtained from a time-course microarray experiment, Liu et al. [1] developed a new algorithm for clustering genes with similar expression profiles over time. Performance of their proposal was compared with three other methods including the order-restricted inference based methodology of Peddada et al. [2, 3]. In this note we point out several inaccuracies in Liu et al. [1] and conclude that the order-restricted inference based methodology of Peddada et al. (programmed in the software ORIOGEN) indeed operates at the desired nominal Type 1 error level, an important feature of a statistical decision rule, while being computationally substantially faster than indicated by Liu et al. [1].     

Embryonic stem cells and mice expressing different GFP variants for multiple non-invasive reporter usage within a single animal

Background  

Non-invasive autofluorescent reporters have revolutionized lineage labeling in an array of different organisms. In recent years green fluorescent protein (GFP) from the bioluminescent jellyfish Aequoria Victoria has gained popularity in mouse transgenic and gene targeting regimes [1]. It offers several advantages over conventional gene-based reporters, such as lacZ and alkaline phosphatase, in that its visualization does not require a chromogenic substrate and can be realized in vivo. We have previously demonstrated the utility and developmental neutrality of enhanced green fluorescent protein (EGFP) in embryonic stem (ES) cells and mice [2].     

Environmental impacts of conventional plastic and bio-based carrier bags

Background, aim, and scope  

The use of bio-based products as carrier bags, packaging materials, and many other applications has been increasingly replacing conventional polymer products. One of the main driving forces of bio-plastic applications is the perceived depletion and scarcity of fossil fuels, especially petroleum. However, despite being introduced as an environmentally friendly alternative to plastics made from crude oil, the environmental benefits of bio-plastics remain debatable. This article serves to investigate whether or not bio-based materials are environmentally friendlier options compared to plastics and attempts to explain the rationale of the results.     

Systematic error detection in experimental high-throughput screening

Background  

High-throughput screening (HTS) is a key part of the drug discovery process during which thousands of chemical compounds are screened and their activity levels measured in order to identify potential drug candidates (i.e., hits). Many technical, procedural or environmental factors can cause systematic measurement error or inequalities in the conditions in which the measurements are taken. Such systematic error has the potential to critically affect the hit selection process. Several error correction methods and software have been developed to address this issue in the context of experimental HTS [1–7]. Despite their power to reduce the impact of systematic error when applied to error perturbed datasets, those methods also have one disadvantage - they introduce a bias when applied to data not containing any systematic error [6]. Hence, we need first to assess the presence of systematic error in a given HTS assay and then carry out systematic error correction method if and only if the presence of systematic error has been confirmed by statistical tests.