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Background: Electronic cigarettes (e-cigarettes), the smokeless alternative to conventional tobacco cigarettes, have become increasingly popular. E-cigarettes vaporise e-liquid, a solution of highly concentrated nicotine, propylene glycol (PG) and vegetable glycerine (VG). With the popularity of e-cigarettes, e-liquid refills have become easily accessible and several cases of intoxication due to the ingestion of e-liquid have been reported. We provide an overview of these cases, their pathophysiology and patients' characteristics. Methods: We carried out a retrospective evaluation of the scientific literature reporting on cases of liquid nicotine intoxication, using the following inclusion criteria: (1) the article is or contains a case report, (2) describes an intoxication with e-liquid, (3) the substance contains nicotine, and (4) intake is oral, intravenous or subcutaneous. Results: We found 26 case reports describing a total of 31 patients who suffered from e-liquid intoxication. All intoxications up to the age of six were reported as unintentional, whereas nearly all cases from ages 13 to 53 were due to suicide attempts. The three most prevalent symptoms of e-liquid intoxication were tachycardia, altered mental status and vomiting. Eleven cases resulted in the death of the patient. In the survivors, the highest plasma concentration of nicotine was 800 µg L−1, while the lowest concentration in the non-survivors was 1600 µg L−1. Conclusions: There is a mismatch between the generally accepted lethal oral nicotine dose of 60 mg, resulting in approximately 180 µg L−1 plasma concentration, and the 4.4- to 8.9-fold higher lethal plasma concentrations we found in cases of e-liquid intoxication. In these severe intoxications, plasma cotinine concentration does not act as a more reliable indicator of nicotine intoxication than nicotine itself. The ages of the patients display a bimodal distribution. In patients above the age of 10, intoxication results mainly from suicide attempts rather than accidental ingestion. The role of PG and VG in e-liquid intoxications is remarkably unclear. However, the similarity across nicotine and PG toxicity symptoms leads us to believe a cumulative effect cannot be excluded. [ABSTRACT FROM AUTHOR]

In "Petronarratology: A Bioregional Approach to Oil Stories", Bart Welling argues that ecocritics and narratologists have an important role to play in challenging the narratives that help perpetuate the modern world's catastrophic addiction to fossil fuels. Welling builds on the concept of reinhabitation, a central idea in the grassroots bioregional movement, as he explores strategies through which authors have reinhabited (i.e., transformed from within) not just oil-polluted places but problematic energy narratives, such as narratives that euphemize hydrocarbons as "energy" in the first place. Focusing on books by David Gessner and Stephanie LeMenager, Welling identifies six features of reinhabitory petronarratives: (1) they acknowledge their authors' personal debts to oil; (2) they own up to the enmeshment of environmentally oriented ways of thinking in our hydrocarbon-fuelled culture; (3) they make room for the voices of ordinary residents of this culture, including people whose political perspectives clash with those of the authors; (4) they take seriously the reinhabitory capacities of nonhuman beings; (5) they rethink petroleum itself as a new kind of character in the fictions of "petromodernity"; and (6) they describe physical encounters with unprocessed hydrocarbons, thus addressing the massive problems posed by fossil fuels on a productively non-apocalyptic scale. [ABSTRACT FROM AUTHOR]

Individuals differ in thermosensitivity, thermoregulation, and zones of thermoneutrality and thermal comfort. Whereas temperature sensing and -effectuating processes occur in part unconsciously and autonomic, awareness of temperature and thermal preferences can affect thermoregulatory behavior as well. Quantification of trait-like individual differences of thermal preferences and experienced temperature sensitivity and regulation is therefore relevant to obtain a complete understanding of human thermophysiology. Whereas several scales have been developed to assess instantaneous appreciation of heat and cold exposure, a comprehensive scale dedicated to assess subjectively experienced autonomic or behavioral thermoregulatory activity has been lacking so far. We constructed a survey that specifically approaches these domains from a trait-like perspective, sampled 240 volunteers across a wide age range, and analyzed the emergent component structure. Participants were asked to report their thermal experiences, captured in 102 questions, on a 7-point bi-directional Likert scale. In a second set of 32 questions, participants were asked to indicate the relative strength of experiences across different body locations. Principal component analyses extracted 21 meaningful dimensions, which were sensitive to sex-differences and age-related changes. The questions were also assessed in a matched sample of 240 people with probable insomnia to evaluate the sensitivity of these dimensions to detect group differences in a case-control design. The dimensions showed marked mean differences between cases and controls. The survey thus has discriminatory value. It can freely be used by anyone interested in studying individual or group differences in thermosensitivity and thermoregulation. [ABSTRACT FROM AUTHOR]

The biofouling affinity of different polymeric surfaces (polypropylene, polysulfone, polyethylene terephthalate, and polyether ether ketone) in comparison to stainless steel (SS) was studied for the model bacteriumEscherichia coliK12 DSM 498 and native biofilms originating from Rhine water. The biofilm mass deposited on the polymer surfaces was minimized by several magnitudes compared to SS. The cell count and the accumulated biomass ofE. colion the polymer surfaces showed an opposing linear trend. The promising low biofilm formation on the polymers is attributed to the combination of inherent surface properties (roughness, surface energy and hydrophobicity) when compared to SS. The fouling characteristics ofE. colibiofilms show good conformity with the more complex native biofilms investigated. The results can be utilized for the development of new polymer heat exchangers when using untreated river water as coolant or for other processes needing antifouling materials. [ABSTRACT FROM AUTHOR]

A process for recovery of zinc from acid solution with di(2-ethyl hexyl phosphoric acid) (D2EHPA) dissolved in iso-dodecane was carried out at 20°C in a countercurrent tubular membrane extractor using a hollow fiber as solid support. Experiments were performed at different aqueous metal concentrations (0.1-l.0g/L), pH 0.1-2.1, and D2EHPA concentrations (2-8 v%). It was found that both the flux of metal and the extraction extent was highly influenced by the extractant concentration and the pH of the feed solution. Overall mass transfer coefficients were determined and related to the tube side, the membrane, and the shell side mass transfer by varying the aqueous flow rate (0.38-0.80 L/min) and organic flow rate (0.22-0.57 L/min) in countercurrent flow. The overall mass transfer coefficient for zinc extraction ranged from 6.2 × 10-6 m/s to 25.3 × 10-6 m/s. It was concluded that extraction kinetics were a major contributor to the overall resistance to mass transfer. [ABSTRACT FROM AUTHOR]

After graduation many students start working in sectors not related to their field of study or participate in training targeted at work in other sectors. In this article, we look at mobility immediately after graduation from the perspective that educational choices have been made when these pupils had little experience of the actual working life in these professions. We develop a model where students accumulate partially transferable human capital but also learn about their professional preferences at the university and during the first years in the labour market. As a consequence of this newly acquired insight, these young workers might realize that working in another occupational field would better fit their preferences, although they are better equipped to work in their own field. The empirical analysis reveals that if wages are 1% lower due to lower skill transferability, the probability that a graduate who regrets his choice actually switches decreases by 1.4 percentage points, while those who switch on average take 0.3 months additional education. [ABSTRACT FROM AUTHOR]

The implementation of the SIR technique for the amino acid separation from diluted aqueous solutions in a fixed-bed column is presented and a mathematical model for the prediction of the adosrption behavior is developed. Independently determined equilibrium and kinetic parameters are used for the calculation of the breakthrough curves. Fixed-bed parameters, such as axial dispersion and bed porosity, are determined experimently and compared with correlations. Analysis of the Biot and Bodenstein number reveal that the mass transfer through the film liquid around the particles, as well as the axial dispersion in the column, could be neglected at the studied experimental conditions. A simplified mathematical model was found to give the best prediction to the experimental breakthrough curves over a wide range of feed concentrations and flow rates. [ABSTRACT FROM AUTHOR]

In the present work the experimental kinetic data of amino acid reactive sorption on solvent impregnated resins (SIR) and its mathematical description is presented. L-Phenylalanine (L-Phe) is extracted from aqueous solution when impregnating the liquid ion-exchanger tricaprylylmethylammonium chloride (TCMAC) on XAD-resin. Experiments with different resins, ion-exchanger loadings, and L-Phe concentration were made for the determination of the rate controlling mechanism. The experimental results, confirmed by the analysis with the modified shrinking-core model, are in favor of a rate-determining intraparticle kinetics. With respect to its adequate description, three different models were considered. The first is based on Fick's diffusion law, the second one assumes the reaction as a rate determining step, and the third model is a combination of both. [ABSTRACT FROM AUTHOR]

The initial mass transfer rate of acetic acid from the aqueous to the organic phase with tri-n-octylamine and toluene or isododecane as solvents has been studied in a constant interfacial cell area as a function of the stirring speed, concentrations of the transfer species, and the influence of chemical adsorption layers. For a detailed understanding of the mass transfer process, the electrophoretic mobility of oil-in-water droplets for these systems has been measured with a ZETA-sizer. The electrophoretic mobilities of the different reactive extraction systems were investigated for their dependence on the pH value and with different interfacial charges. It was proved that a change of the interfacial charge influences the zeta potential of the dispersed oil drops in the same way as the reaction kinetics, and thus the mass transfer of acetic acid. [ABSTRACT FROM AUTHOR]