MobGeoSen: facilitating personal geosensor data collection and visualization using mobile phones

Mobile sensing and mapping applications are becoming more prevalent because sensing hardware is becoming more portable and more affordable. However, most of the hardware uses small numbers of fixed sensors that report and share multiple sets of environmental data which raises privacy concerns. Instead, these systems can be decentralized and managed by individuals in their public and private spaces. This paper describes a robust system called MobGeoSens which enables individuals to monitor their local environment (e.g. pollution and temperature) and their private spaces (e.g. activities and health) by using mobile phones in their day to day life. The MobGeoSen is a combination of software components that facilitates the phone’s internal sensing devices (e.g. microphone and camera) and external wireless sensors (e.g. data loggers and GPS receivers) for data collection. It also adds a new dimension of spatial localization to the data collection process and provides the user with both textual and spatial cartographic displays. While collecting the data, individuals can interactively add annotations and photos which are automatically added and integrated in the visualization file/log. This makes it easy to visualize the data, photos and annotations on a spatial and temporal visualization tool. In addition, the paper will present ways in which mobile phones can be used as noise sensors using an on-device microphone. Finally, we present our experiences with school children using the above mentioned system to measure their exposure to environmental pollution.

The Reaction of Alkynes with Model Gold Catalysts: Generation of Acetylides,Self-coupling and Surface Decomposition

Catalysis Letters - Alkynes are one of the most important groups of building blocks in organic chemistry as they work as nucleophiles upon deprotonation of its acidic hydrogen. On the surface of a...     

The Enzymatic and Non-Enzymatic Antioxidant System Response of the Seagrass Cymodocea nodosa to Bisphenol-A Toxicity

The effects of environmentally relevant bisphenol A (BPA) concentrations (0.3, 1 and 3 μg L⁻¹) were tested at 2, 4, 6 and 8 days, on intermediate leaves, of the seagrass Cymodocea nodosa. Hydrogen peroxide (H₂O₂) production, lipid peroxidation, protein, phenolic content and antioxidant enzyme activities were investigated. Increased H₂O₂ formation was detected even at the lowest BPA treatments from the beginning of the experiment and both the enzymatic and non-enzymatic antioxidant defense mechanisms were activated upon application of BPA. Elevated H₂O₂ levels that were detected as a response to increasing BPA concentrations and incubation time, led to the decrease of protein content on the 4th day even at the two lower BPA concentrations, and to the increase of the lipid peroxidation at the highest concentration. However, on the 6th day of BPA exposure, protein content did not differ from the control, indicating the ability of both the enzymatic and non-enzymatic mechanisms (such as superoxide dismutase (SOD) and phenolics) to counteract the BPA-derived oxidative stress. The early response of the protein content determined that the Low Effect Concentration (LOEC) of BPA is 0.3 μg L⁻¹ and that the protein content meets the requirements to be considered as a possible early warning “biomarker” for C. nodosa against BPA toxicity.     

BDD anodic oxidation as tertiary wastewater treatment for the removal of emerging micro‐pollutants,pathogens and organic matter

This work reports for the first time the removal of 17α‐ethynylestradiol (EE2), a synthetic estrogen hormone, from secondary treated effluents by electrochemical oxidation. Experiments were conducted in a single compartment reactor comprising a boron‐doped diamond (BDD) anode and a zirconium cathode. EE2, in the range 100–800 µg L^?1, was spiked in the post‐chlorination effluent of a municipal treatment plant and oxidized at 0.9–2.6 mA cm^?2 current density. Complete degradation of 100 µg L^?1 EE2 was achieved in 7 min at 2.1 mA cm^?2 and inherent conditions, while the addition of 0.1 mol L^?1 NaCl achieved removal in just a few seconds. The process was then tested in the pre‐chlorination effluent at 2.1 mA cm^?2 and inherent conditions; complete E. coli killing and EE2 removal occurred in just 1.5 and 3.5 min, respectively, while overall estrogenicity (assessed by the YES assay) and residual organic matter (in terms of chemical oxygen demand (COD)) decreased by 50% and 85% after 30 min, respectively. These results clearly show the potential of BBD electrochemical oxidation to serve as an efficient tertiary wastewater treatment. Copyright © 2011 Society of Chemical Industry     

DNA damage induction by two halogenated acetaldehydes, byproducts of water disinfection

Drinking water contains disinfection byproducts, generated by the interaction of chlorine (or other disinfecting chemicals) with organic matter, anthropogenic contaminants, and bromide/iodide naturally present in most source waters. One class of these chemicals is the halogenated acetaldehydes (HAs), identified in high quantities when ozone is used as primary or secondary disinfectant. In this study, an analysis of the genotoxic potential of two HAs, namely tribromoacetaldehyde (TBA) and chloral hydrate (CH) has been conducted in human cells (TK6 cultured cells and peripheral blood lymphocytes). The comet assay was used to 1) measure the induction of single and double-strand DNA breaks, 2) evaluate the capacity of inducing oxidative DNA damage, and 3) determine the DNA repair kinetics of the induced primary genetic damage. In addition, chromosome damage, as a measure of fixed damage, was evaluated by means of the micronucleus test. The results of the comet assay show that both compounds are clearly genotoxic, inducing high levels of DNA breaks, TBA being more effective than CH. According to the comet results, both HAs produce high levels of oxidized bases, and the induced DNA damage is rapidly repaired over time. Contrarily, the results obtained in the micronucleus test, which measures the capacity of genotoxic agents to induce clastogenic and aneugenic effects, are negative for the two HAs tested, either using TK6 cells or human peripheral blood lymphocytes. This would indicate that the primary damage induced by the two HAs is not fixed as chromosome damage, possibly due to an efficient repair or the death of damaged cells, which is an important point in terms of risk assessment of DBPs exposure.     

Assessing readiness for change in the eating disorders: The psychometric properties of the readiness and motivation interview.

This study examined the psychometric properties of the Readiness and Motivation Interview (RMI), a symptom-specific measure of readiness and motivation for change in the eating disorders. For 4 symptom domains, the RMI assesses the extent to which individuals are in precontemplation, contemplation, and action/maintenance, and the extent to which change is made for internal versus external reasons. Ninety-nine individuals with eating disorders completed the RMI and measures to assess convergent, divergent, and criterion validity. RMI profiles revealed differences in readiness and motivation across symptom domains. The RMI demonstrated good reliability and construct validity, and RMI scores predicted anticipated difficulty of recovery activities, completion of recovery activities, decision to enroll in an intensive symptom-reduction program, and treatment dropout. The RMI may have important clinical applications by providing much-needed information on client readiness for action-oriented treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hydrochlorination of oleic acid: Kinetics and Henry's constant

The addition reaction of gaseous hydrogen chloride to oleic acid (hydrochlorination) was investigated. Oleic acid was placed in an autoclave chamber, into which gaseous hydrogen chloride was fed, and the reaction was carried out under batch and semiflow conditions. The hydrochlorination of oleic acid by hydrogen cloride is a gas-liquid reaction involving the initial absorption of hydrogen chloride into a quiescent liquid, accompanied by a reaction of the dissolved gas with the liquid to form chlorostearic acid. The course of the reaction was monitored by withdrawing oil samples at 30-min intervals and determining the iodine value, acid value, and chlorine content. The kinetics of hydrochlorination was studied at constant pressure (40 atm). The experimental data were fitted to an irreversible pseudo zero-order rate equation with the reaction constant k=2.293×10⁻⁷ mol/cm³·s. The solubility of HCl (Henry's constant) in chlorostearic acid was estimated from two types of batch experiments, including a single and double feed of HCl. The mean Henry's constant value for physical absorption was 3218 atm cm³/mol in the pressure range of 11.2–16 atm and at a temperature of 21°C. Similar batch experiments were performed in oleic acid, and the results supported the Henry's constant value determined for chlorostearic acid.     

Effect of nonionic surfactants on the solubilization of alachlor

The ability of nonionic surfactants to solubilize the pesticide alachlor was studied. Two homologue series, octylphenol ethoxylates (Triton X-114, Triton X-100 and Triton X-102) and ethoxylated decyl alcohols (Neodol 91-5E, Neodol 91-6E and Neodol 91-8E) were used at concentrations 3 critical micelle concentration (CMC) and 6 CMC. The rate of solubilization of a sufficient quantity of alachlor (for saturation) in aqueous solution containing the micelles of nonionic surfactant was recorded. The experimental data were fitted to a first-order kinetic model. The rate constant, saturation concentration and enhancement factor were estimated for each surfactant system. The effect of surfactant structure, CMC concentration, pesticide structure and its physicochemical properties on the effectiveness of solubilization was determined. In terms of solubilization capability, the nonionic surfactants of each homologue series can be ranked as follows: Neodol 91-8E>Neodol 91-6E>Neodol 91-5E and Triton X-102>Triton X-100>Triton X-114. The more hydrophilic Neodol series was proved more efficient in alachlor solubilization than Triton series. The enhancement factor values ranged from 1.064 to 1.995 at 3 CMC and 1.320 to 2.919 at 6 CMC. The results will be used mainly for micellar-enhanced ultrafiltration since the extent of solubilization is a critical factor.