The Life-Cycle of Chlorine, Part I: Chlorine Production and the Chlorine-Mercury Connection

Chlorine is an important industrial chemical. Not only is it a component of many important products, it is also needed for many chemical manufacturing processes, even where it does not appear in the final product. But a number of chlorine chemicals, especially organochlorines, are toxic, carcinogenic, tentogenic or otherwise potentially disturbing to the environment. For this reason, some environmentalists—notably Greenpeace-have advocated a ban, not just on some products but on all uses of elemental chlorine. The chemical industry is taking this threat seriously and mounting a vigorous defense. But the debate so far is not illuminating the issues effectively, because both sides are selectively using questionable and unverifiable data.
The scientific uncertainties are not really the problem. Rather, data in the public domain and accessible to environmentalists and even regulatory authorities are of very poor qualrty. Because of industry secrecy much crucial inforrnation is unavailable and some of what is available is misleading or wrong. The dual purposes of this article, and the ones that follow, are (I) to elucidate the information requirements for an adequate life-cycle analysis of chlorine and its uses and (2) to indicate how and where the use of massbalance methodology can help identify errors and fill in gaps.
The present article deals with electrolytic chlorine produdion and mercury flows arising from chlorine production. Subsequent articles deal with conversion processes and losses and further chemical industry uses of chlorine, major end uses of chlorine and chlorine chemicals, and persistent organochlorine pollutants.     

Anaerobic treatment of low-strength synthetic TCF effluents and biomass adhesion in fixed-bed systems

Toxicity effects produced by kraft mill effluents are due to the productive process. New bleaching processes have been proposed (e.g. total chlorine free, TCF) to reduce the production of toxic chlorine compounds. In the TCF processes large amounts of chelating compounds like the ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DPTA) are used. The aim of this work is to research the feasibility of the degradation of low-strength synthetic TCF effluents in a anaerobic filter reactor (AF) and the biomass adhesion. The effects on the operation of the AF at different EDTA loading rates were tested in the range from 0.07 to 0.51 g EDTA l(-1) days(-1). The maximum EDTA removal percentage achieved was of 27%. Acute toxicity (measured as 24 h-LC(50)) with Daphnia magna was reduced from 14.23 to 54.53% before and after anaerobic treatment, respectively. Observations of biomass samples from the AF under the scanning microscope verified the attached biomass.     

Environmental impacts of conventional plastic and bio-based carrier bags

Background, aim, and scope  

Worldwide, the production of biodegradable and compostable plastics has steadily grown. In Part 1 (Khoo et al. 2010), life cycle assessment (LCA) was applied to compare the production stages of a bio-based bag (made from polyhydroxyalkanoate or bio-plastic (PHA)) with polyethylene plastic bag. The scope of the study is within the context of Singapore and does not include other types of conventional or bio-based polymers (e.g., polylactic acid (PLA), thermoplastics, high-density polyethylene (HDPE), EPS, etc). This article (part 2) proposes to investigate the end-of-life options of both bags.     

1-Iodo-2 methylundecane [1I2MU]: An estrogen-dependent urinary sex pheromone of female mice

In our previous investigations [1], urine of female mice contained specific compounds, namely isocroctylhydrazine, 4-methyl-2-heptanone, and azulene during proestrus, whereas during estrus it contained 1-H-cyclopop.e.azulene, caryophyllene, and copanene. Furthermore, 1-iodo-2 methyl undecane (1I2MU), present during both proestrus and estrus, was regarded as a putative estrus-specific chemo-signal [1]. The primary objective of the present study was to determine the estrogen-dependency of the above-mentioned compounds, including 1I2MU. Furthermore, the effect of these compounds on pre-mating behavior, e.g., sniffing, licking, and grooming, were recorded to determine their role as sex pheromones. Based on gas chromatography linked mass spectrometry (GC-MS) of urine samples, profiles in oophorectomized female mice had 14 major peaks. Furthermore, neither 1I2MU (nor other estrus-specific compounds) were detected in the urine of these mice, although they were detected in urine of proestrus and estrus mice. In addition, 1I2MU was not detected in urine of prepubertal mice. It was noteworthy that both 1I2MU and 4-methyl-2-heptanone reappeared in estrogen-treated females. Based on pre-mating behavioral analysis, 1I2MU was the compound most preferred by males. In conclusion, production of 1I2MU was estrogen-dependent in females, and it enhanced reproductive activities in males.     

Student-oriented learning: an inquiry-based developmental biology lecture course

In this junior-level undergraduate course, developmental life cycles exhibited by various organisms are reviewed, with special attention--where relevant--to the human embryo. Morphological features and processes are described and recent insights into the molecular biology of gene expression are discussed. Ways are studied in which model systems, including marine invertebrates, amphibia, fruit flies and other laboratory species are employed to elucidate general principles which apply to fertilization, cleavage, gastrulation and organogenesis. Special attention is given to insights into those topics which will soon be researched with data from the Human Genome Project. The learning experience is divided into three parts: Part I is a in which the Socratic (inquiry) method is employed by the instructor (GMM) to organize a review of classical developmental phenomena; Part II represents an in which students study the details related to the surveys included in Part I as they have been reported in research journals; Part III focuses on a class project--the preparation of a spiral bound on a topic of relevance to human developmental biology (e.g.,Textbook of Embryonal Stem Cells). Student response to the use of the Socratic method increases as the course progresses and represents the most successful aspect of the course.     

Understanding the future of lithium: Part 2, temporally and spatially resolved life‐cycle assessment modeling

An array of emerging technologies, from electric vehicles to renewable energy systems, relies on large‐format lithium ion batteries (LIBs). LIBs are a critical enabler of clean energy technologies commonly associated with air pollution and greenhouse gas mitigation strategies. However, LIBs require lithium, and expanding the supply of lithium requires new lithium production capacity, which, in turn, changes the environmental impacts associated with lithium production since different resource types and ore qualities will be exploited. A question of interest is whether this will lead to significant changes in the environmental impacts of primary lithium over time. Part one of this two‐part article series describes the development of a novel resource production model that predicts future lithium demand and production characteristics (e.g., timing, location, and ore type). In this article, part two, the forecast is coupled with anticipatory life‐cycle assessment (LCA) modeling to estimate the environmental impacts of producing battery‐grade lithium carbonate equivalent (LCE) each year between 2018 and 2100. The result is a normalized life‐cycle impact intensity for LCE that reflects the changing resource type, quantity, and region of production. Sustained growth in lithium demands through 2100 necessitates extraction of lower grade resources and mineral deposits, especially after 2050. Despite the reliance on lower grade resources and differences in impact intensity for LCE production from each deposit, the LCA results show only small to modest increases in impact, for example, carbon intensity increases from 3.2 kg CO₂e/kg LCE in 2020 to 3.3 kg CO₂e/kg LCE in 2100.     

Molecular mass and location of the most abundant peak of the molecular ion isotopomeric cluster

The location of the most abundant peak of the molecular-ion pattern often differs from the molecular mass published in scientific databases. The location is also distinct from the value expected from average atomic masses. The cause of this phenomenon is a large number of atoms of carbon, sulfur, chlorine, bromine, silicon and boron. This due to the natural isotope abundances of some elements forming organic compounds. A parameter called location of the most abundant peak of an isotopometric cluster (LAPIC) denotes the location of the most abundant (the main) peak of an isotopomeric cluster, which is determined, e.g., by mass spectrometry and can be important for medium- and high-molecular mass compounds. The equations for LAPIC calculation are presented for elements usually observed in organic compounds. The LAPIC with elemental formula helps effectively, e.g., in mass spectra interpretation since the prediction of LAPIC allows the correct connection of the main peak of the investigated ion with the expected ion formula and the mass of the ion considered. This solution can be a substitute for the much more complex method of isotopometric analysis applied in mass spectra interpretation. [Figure: see text]. Differences of the most abundant peak location (Delta LAPIC(C)=f(n)) for carbon aggregates C(n).     

Cadmium Flows Caused by the Worldwide Production of Primary Zinc Metal

Material flows of the economic cycle can contain toxic substances, which enter the economy as impurities in raw materials or are intentionally added as minor or even main constituents during the manufacture of industrial or consumer goods. Cadmium, predominantly associated with zinc minerals, is a by-product of the primary zinc production. Cadmium is generated when zinc is extracted from zinc ores and concentrates, an intermediate product resulting from flotation processing after the zinc ore has been mined and milled. Information on the amount of cadmium generated from zinc extraction is rarely published. In this article, we assess generation and fate of cadmium accumulating worldwide in the production of primary zinc from ores and concentrates. Model calculations for the beginning of the 21st century show that annually about 30,000 tonnes of cadmium were generated, but only approximately 16,000 tonnes were converted to primary cadmium metal, key material for the production of other cadmium compounds (e.g., cadmium oxide), and cadmium-containing goods (e.g., nickel−cadmium batteries). Hence, about 14,000 tonnes of cadmium must have been transferred somewhere else. The fate of about 5,500 tonnes can be plausibly explained, but it is difficult to determine what happens to the rest.     

Affinity chromatography as a method for sample preparation in gas chromatography/mass spectrometry.

Analytical chemistry aims at developing analytical methods and techniques for unequivocal identification and accurate quantitation of natural and synthetic compounds in a given matrix. Analytical methods based on the mass spectrometry (MS) technology, e.g., GC/MS and LC/MS and their variants, GC/tandem MS and LC/tandem MS, are best suited both for qualitative and quantitative analyses. GC/MS methods not only serve as reference methods, e.g., in clinical chemistry, but they are now widely and routinely used for quantitative determination of numerous analytes. However, despite inherent accuracy, analytical methods based on GC/MS commonly consist of several analytical steps, including extraction and derivatization of the analyte. In general, unequivocal identification and accurate quantification of an analyte in very low concentrations in complex matrices require further chromatographic techniques, such as high-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC) for sample purification. In recent years, affinity chromatography (e.g., boronate and immunoaffinity chromatography) has been developed to a superior technique for sample preparation of numerous classes of compounds in GC/MS. In this article, the application and importance of affinity chromatography as a method for sample preparation in modern quantitative GC/MS method is described and discussed, using as examples various natural and synthetic compounds, such as arachidonic acid derivates, nitrosylated and nitrated proteins, steroids, drugs, and toxins.     

The evolution of costly displays,cooperation and religion: credibility enhancing displays and their implications for cultural evolution

This paper lays out an evolutionary theory for the cognitive foundations and cultural emergence of the extravagant displays (e.g., ritual mutilation, animal sacrifice and martyrdom) that have so tantalized social scientists, as well as more mundane actions that influence cultural learning and historical processes. In Part I, I use the logic of natural selection to build a theory for how and why seemingly costly displays influence the cognitive processes associated with cultural learning — why do “actions speak louder than words?” The core idea is that cultural learners can both avoid being manipulated by their models (those they are inclined to learn from) and more accurately assess their belief commitment by attending to displays or actions by the model that would seem costly to the model if he held beliefs different from those he expresses verbally. Part II examines the implications for cultural evolution of this learning bias in a simple evolutionary model. The model reveals the conditions under which this evolved bias can create stable sets of interlocking beliefs and practices, including quite costly practices. Part III explores how cultural evolution, driven by competition among groups or institutions stabilized at alternative sets of these interlocking belief-practice combinations, has led to the association of costly acts, often in the form of rituals, with deeper commitments to group beneficial ideologies, higher levels of cooperation within groups, and greater success in competition with other groups or institutions. I close by discussing the broader implications of these ideas for understanding various aspects of religious phenomena.     

Effects of tumors on inhaled pharmacologic drugs

Lung carcinomas are now the most common form of cancer. Clinical data suggest that tumors are found preferentially in upper airways, perhaps specifically at carina within bifurcations. The disease can be treated by aerosolized pharmacologic drugs. To enhance their efficacies site-specific drugs must be deposited selectively. Since inhaled particles are transported by air, flow patterns will naturally affect their trajectories. Therefore, in Part I of a systematic investigation, we focused on tumor-induced effects on airstreams, in Part II (the following article [p. 245]), particle trajectories were determined. To facilitate the targeted delivery of inhaled drugs, we simulated bifurcations with tumors on carinas using a commercial computational fluid dynamics (CFD) software package (FIDAP) with a Cray T90 supercomputer and studied effects of tumor sizes and ventilatory parameters on localized flow patterns. Critical tumor sizes existed; e.g., tumors had dominant effects when r/R > or = 0.8 for bifurcation 3-4 and r/R > or = 0.6 for bifurcation 7-8 (r = tumor radius and R = airway radius). The findings suggest that computer modeling is a means to integrate alterations to airway structures caused by diseases into aerosol therapy protocols.     

How much can we know about the causes of evolutionary trends?

One of the first questions that paleontologists ask when they identify a large-scale trend in the fossil record (e.g., size increase, complexity increase) is whether it is passive or driven. In this article, I explore two questions about driven trends: (1) what is the underlying cause or source of the directional bias? and (2) has the strength of the directional bias changed over time? I identify two underdetermination problems that prevent scientists from giving complete answers to these two questions.     

Inhibitory effects of Carpinus tschonoskii leaves extract on CpG-stimulated pro-inflammatory cytokine production in murine bone marrow-derived macrophages and dendritic cells

This report describes the anti-inflammatory effects of MeOH extract from leaves of Carpinus tschonoskii (CE) on primary bone marrow-derived macrophage (BMDMs) and dendritic cells (BMDCs). Primary BMDMs and BMDCs were used for pro-inflammatory cytokine production and Western blot analysis. Human embryonic kidney cell line 293?T (HEK293?T) was used to access NF-κB activity. In all cases, CpG DNA was used to stimulate the cells. The CE (0-150?μg/ml) was treated to BMDMs, BMDCs, and HEK293T cells. CE pre-treatment in CpG-stimulated BMDMs and BMDCs showed a dose-dependent inhibitory effect on pro-inflammatory cytokine (e.g., IL-12 p40, IL-6, and TNF-α) production as compared to non-treated controls. The CE pre-treatment had no significant inhibition on mitogen-activated protein kinases (MAPKs) phosphorylation but strongly inhibited IκBα degradation. In NF-κB reporter gene assay, the CE pre-treatment inhibited NF-κB-dependent luciferase activity in a dose-dependent manner. Taken together, these data suggest that CE has significant inhibitory effect on pro-inflammatory cytokine production and warrant further studies concerning potentials of CE for medicinal uses.     

Metabolic fingerprinting of rat urine by LC/MS Part 1. Analysis by hydrophilic interaction liquid chromatography-electrospray ionization mass spectrometry

Complex biological samples, such as urine, contain a very large number of endogenous metabolites reflecting the metabolic state of an organism. Metabolite patterns can provide a comprehensive signature of the physiological state of an organism as well as insights into specific biochemical processes. Although the metabolites excreted in urine are commonly highly polar, the samples are generally analyzed using reversed-phase liquid chromatography mass spectrometry (RP-LC/MS). In Part 1 of this work, a method for detecting highly polar metabolites by hydrophilic interaction liquid chromatography-electrospray ionization mass spectrometry (HILIC/ESI-MS) is described as a complement to RP-LC/ESI-MS. In addition, in an accompanying paper (Part 2), different multivariate approaches to extracting information from the resulting complex data are described to enable metabolic fingerprints to be obtained. The coverage of the method for the screening of as many metabolites as possible is highly improved by analyzing the urine samples using both a C(18) column and a ZIC-HILIC column. The latter was found to be a good alternative when analyzing highly polar compounds, e.g., hydroxyproline and creatinine, to columns typically used for reversed-phase liquid chromatography.     

LBA technique in the detection of chromosome variants

Summary A method is described (LBA method) which uses DNA replication pattern in the detection of chromosome variants in man. In Part I, results on chromosomes with known sites of Q-variants, i.e., 5 pairs of acrocentrics, as well as 3 and 4, were presented.Fourty-one variants were detected in a total of 40 acrocentrics. Twentyeight of them were detected only by the LBA technique; 11 of them being in short arms and 17 of them in centromeres. Seven variants, including 4 of those in satellites, were detected only in QFQ-stained metaphases. Six short-arm variants were observed by both methods. It appears that a sequential QFQ-LBA technique is very useful in the detection of variants in D- or G-group chromosomes.     

Conception of a Bioelectromagnetic Signal System via the Collagen Fibril Network; Biochemical Conclusions and Underlying Coherent Mechanism. II. Energetic Aspects,Acid and Neutral Proteases,and the Phenomenon of Coherence

This paper presents a bioelectrical conception of connective tissue regulation in bone, cartilage, and tendon, as well as other mechanically stressed connective tissues, based on the biological hypothesis of a biosensor and nerve-like signal conducting function of the native collagen fibril in the extracellular matrix. The various levels of existing conceptions of bioelectrical connective tissue regulation as well as some questions of classical connective tissue research (e.g., neutral and acid protease activity) are discussed from this electrophysiological point of view. Part I presented the topic in the form of classical biophysics and physicochemistry. This paper, Part II, makes use of the concept for a discussion of the “living state” of the extracellular matrix, biochemical aspects of acid and neutral protease activity, and nanoelectronic, relativistic, and coherent aspects of connective tissue regulation.     

Toxicants inhibiting anaerobic digestion: A review

Anaerobic digestion is increasingly being used to treat wastes from many sources because of its manifold advantages over aerobic treatment, e.g. low sludge production and low energy requirements. However, anaerobic digestion is sensitive to toxicants, and a wide range of compounds can inhibit the process and cause upset or failure. Substantial research has been carried out over the years to identify specific inhibitors/toxicants, and their mechanism of toxicity in anaerobic digestion. In this review we present a detailed and critical summary of research on the inhibition of anaerobic processes by specific organic toxicants (e.g., chlorophenols, halogenated aliphatics and long chain fatty acids), inorganic toxicants (e.g., ammonia, sulfide and heavy metals) and in particular, nanomaterials, focusing on the mechanism of their inhibition/toxicity. A better understanding of the fundamental mechanisms behind inhibition/toxicity will enhance the wider application of anaerobic digestion.     

A new catheter for tumor-targeting with radioactive microspheres in representative hepatic artery systems--part II: solid tumor-targeting in a patient-inspired hepatic artery system

In this second part, the methodology for optimal tumor-targeting is further explored, employing a patient-inspired hepatic artery system which differs significantly from the idealized configuration discussed in Part I. Furthermore, the fluid dynamics of a microsphere supply apparatus is also analyzed. The best radial catheter positions and particle-release intervals for tumor targeting were determined for both the idealized and patient-inspired configurations. This was accomplished by numerically analyzing generated particle release maps (PRMs) for ten equally spaced intervals throughout the pulse. As in Part I, the effects of introducing a catheter were also investigated. In addition to the determination of micro-catheter positioning and, hence, optimal microsphere release, a microsphere-supply apparatus (MSA) was analyzed, which transports the particles to the catheter-nozzle, considering different axial particle injection functions, i.e., step, ramp, and S-curve. A refined targeting methodology was developed which demonstrates how the optimal injection region and interval can be determined with the presence of a catheter for any geometric configuration. Additionally, the less abrupt injection functions (i.e., ramp and S-curve) were shown to provide a more compact particle stream, making them better choices for targeting. The results of this study aid in designing the smart micro-catheter (SMC) in conjunction with the MSA, bringing this innovative treatment procedure one step closer to implementation in clinical practice.