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Halogen bonding (XB) was here proposed, for the first time, as a solubilization mechanism for increasing efficiency in the liquid-liquid microextraction of halogenated compounds. The approach was illustrated by the extraction of hexabromocyclododecane (HBCD) enantiomers in natural waters with a supramolecular solvent (SUPRAS) made up of inverted hexagonal aggregates of decanoic acid. The XB and dispersion interactions offered by the SUPRAS were able to extract the six HBCD enantiomers (i.e. (+)-α-, (-)-α- (+)-ß-, (-)-ß-, (+)-γ- and (-)-γ-) quantitatively (e.g. recoveries in the range 89-106%) and reach concentration factors as high as 720 without the need for solvent evaporation. HBCD enantiomers in the SUPRAS extract were directly analysed by chiral liquid chromatography coupled to tandem mass spectrometry (LCMS/MS). Quantitation limits of the method (0.09-0.9 ng L-1) were below the quality standard stablished by the European Union for HBCDs in inland surface water samples (1.6 ng L-1), and the precision, expressed as relative standard deviation (n = 6), was below 9% for all the HBCD enantiomers at concentrations within the range 50-500 ng L-1. The method was successfully applied to the enantioselective determination of HBCDs in the dissolved and the particle-bound fractions of river waters containing different concentration of suspended particles (10-57.8 mg L-1) that were spiked at two concentration levels (10 and 100 ng L-1). The results here obtained prove that XB is a valuable mechanism for the solubilisation of halogenated compounds that can effectively increase their recovery from liquid and solid samples.

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Halogen bonding (XB), a highly energetic and directional interaction, is here proposed as a new mechanism to increase solute solubilisation in solvent extractions. The approach is illustrated by the extraction of hexabromocyclododecane (HBCD) enantiomers in soils and sediments using supramolecular solvents (SUPRAS) containing XB donors in their structure. SUPRAS consisting of inverted hexagonal aggregates of decanoic acid, synthesized by water-induced coacervation of the amphiphile in tetrahydrofuran (THF), were explored for this purpose. Sample treatment involved the extraction of 400 mg of soil or sediment with 250 µL of SUPRAS for 5 min and then centrifugation for 10 min. SUPRAS extracts were directly analyzed by chiral liquid chromatography tandem mass spectrometry (LC-MS/MS) and quantification was carried out using isotopically labelled internal standards. Quantitative recoveries (93-102%) were obtained for the six HBCD enantiomers in both fresh and aged spiked samples. The mild experimental conditions required for extraction (room temperature and atmospheric pressure), the low SUPRAS volume/sample amount ratio needed (0.6 mL g─1), the short time required for sample treatment (15 min), and the simplicity of the procedure (use of conventional equipment and the possibility of treating several samples simultaneously), makes this method clearly superior to those previously reported. Method quantitation limits were in the intervals 0.58-2.23 ng g─1, and the relative standard deviations (n = 18, HBCD stereoisomer concentration = 50 ng g─1) obtained under repeatability and reproducibility conditions varied within the ranges 1.0-4% and 2.5-5%, respectively. The approach here described could be easily extended to the extraction of brominated flame retardants in different types of matrices.

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KEY MESSAGE: For the first time, fine mapping for sfl locus was carried out using a battery of new STMS and SNP markers. The target region was delimited to 92.6 Kb where seven annotated genes were found that could be candidate genes for the simple/double podding trait in chickpea. Four recombinant inbred populations (RIP-1, RIP-7, RIP-11, and CPR-01) were used to map the double podding gene (sfl) in chickpea. In RIP-1, the gene was initially mapped on linkage group (LG) 6 between the two sequence-tagged microsatellite site (STMS) markers TA120 and TR1. Eight new STMS markers were added onto LG6 in the target region and sfl locus was finally located between CAGM27819 and CAGM27777 markers within an interval of 2 cM. Seven out of the eight markers were mapped in RIP-7 and its reciprocal RIP-11 confirming the location of the sfl locus to a 4.8 cM interval flanked by TR44 and CAGM27705. Furthermore, using a high-density single nucleotide polymorphism (SNP) map of CPR-01, sfl was mapped to the same genomic region in a 5.1 cM interval between TR44 and the SNP scaffold1646p97220. Five pairs of near isogenic lines (NILs) and eight recombinant inbred lines (RILs) were used to refine this region in the chickpea physical map. Combining data from linkage analysis in four RIPs, marker physical positions and recombination events obtained in both pairs of NILs and selected RILs, sfl could be placed within a genomic window of 92.6 Kb. Seven annotated genes were extracted from this region. The regulator of axillary meristem-predicted gene could be a candidate gene for the simple/double podding gene. This study provides additional set of markers flanking and tightly linked to sfl locus that are useful for marker-assisted selection.

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This manuscript describes, for the first time, the simultaneous enantioselective determination of ibuprofen, naproxen and ketoprofen in wastewater based on liquid chromatography tandem mass spectrometry (LC-MS/MS). The method uses a single-step sample treatment based on microextraction with a supramolecular solvent made up of hexagonal inverted aggregates of decanoic acid, formed in situ in the wastewater sample through a spontaneous self-assembly process. Microextraction of profens was optimized and the analytical method validated. Isotopically labeled internal standards were used to compensate for both matrix interferences and recoveries. Apparent recoveries for the six enantiomers in influent and effluent wastewater samples were in the interval 97-103%. Low method detection limits (MDLs) were obtained (0.5-1.2 ng L(-1)) as a result of the high concentration factors achieved in the microextraction process (i.e. actual concentration factors 469-736). No analyte derivatization or evaporation of extracts, as it is required with GC-MS, was necessary. Relative standard deviations for enantiomers in wastewater were always below 8%. The method was applied to the determination of the concentrations and enantiomeric fractions of the targeted analytes in influents and effluents from three wastewater treatment plants. All the values found for profen enantiomers were consistent with those previously reported and confirmed again the suitability of using the enantiomeric fraction of ibuprofen as an indicator of the discharge of untreated or poorly treated wastewaters. Both the analytical and operational features of this method make it applicable to the assessment of the enantiomeric fate of profens in the environment.

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A simple, sensitive, rapid and economic method was developed for the quantification of enantiomers of chiral pesticides as mecoprop (MCPP) and dichlorprop (DCPP) in soil samples using supramolecular solvent-based microextraction (SUSME) combined with liquid chromatography coupled to mass spectrometry (LC-MS/MS). SUSME has been described for the extraction of chiral pesticides in water, but this is firstly applied to soil samples. MCPP and DCPP are herbicides widely used in agriculture that have two enantiomeric forms (R- and S-) differing in environmental fate and toxicity. Therefore, it is essential to have analytical methods for monitoring individual DCPP and MCPP enantiomers in environmental samples. MCPP and DCPP were extracted in a supramolecular solvent (SUPRAS) made up of dodecanoic acid aggregates, the extract was dried under a nitrogen stream, the two herbicides dissolved in acetate buffer and the aqueous extract directly injected in the LC-MS/MS system. The recoveries obtained were independent of soil composition and age of herbicide residues. The detection and quantitation limits of the developed method for the determination of R- and S-MCPP and R- and S-DCPP in soils were 0.03 and 0.1 ng g(-1), respectively, and the precision, expressed as relative standard deviation (n=6), for enantiomer concentrations of 5 and 100 ng g(-1) were in the ranges 4.1-6.1% and 2.9-4.1%. Recoveries for soil samples spiked with enantiomer concentrations within the interval 5-180 ng g(-1) and enantiomeric ratios (ERs) of 1, 3 and 9, ranged between 93 and 104% with standard deviations of the percent recovery varying between 0.3% and 6.0%. Because the SUPRAS can solubilize analytes through different type of interactions (dispersion, dipole-dipole and hydrogen bonds), it could be used to extract a great variety of pesticides (including both polar and non-polar) in soils.

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Liquid chromatography (LC)/tandem mass spectrometry (MS/MS) after supramolecular solvent-based microextraction (SUSME) was firstly used in this work for the enantioselective determination of chiral pesticides in natural waters. The method developed for the quantitation of the R- and S-enantiomers of mecoprop (MCPP) and dichlorprop (DCPP) involved the extraction of the herbicides in a supramolecular solvent (SUPRAS) made up of reverse aggregates of dodecanoic acid (DoA), analyte re-extraction in acetate buffer (pH = 5.0), separation of the target enantiomers on a chiral column of permethylated α-cyclodextrin under isocratic conditions, and detection of the daughter ions (m/z = 140.9 and 160.6 for MCPP and DCPP, respectively) using a hybrid triple quadrupole mass spectrometer equipped with an electrospray source operating in the negative ion mode. Similar recoveries (ca. 75%) and actual concentration factors (ca. 94) were obtained for both phenoxypropanoic acids (PPAs). The quantitation limits were 1 ng L(-1) for R- and S-MCPP, and 4 ng L(-1) for R- and S-DCPP, and the precision, expressed as relative standard deviation (n = 6) was in the ranges 2.4-2.7% ([R-MCPP] = [S-MCPP] = 5 ng L(-1) and [R-DCPP] = [S-DCPP] = 15 ng L(-1)) and 1.6-1.8% (100 ng L(-1) of each enantiomer). The SUSME-LC-MS/MS method was successfully applied to the determination of the enantiomers of MCPP and DCPP in river and underground waters, fortified at concentrations between 15 and 180 ng L(-1) at variable enantiomeric ratios (ER = 1-9).

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A single-step, environmentally friendly sample treatment was developed and used in combination with liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the quantitation of hexabromocyclododecane (HBCD) stereoisomers in fish. It was based on the microextraction of the stereoisomers with a supramolecular solvent (SUPRAS) made up of reverse aggregates of decanoic acid (DeA). The procedure involved the stirring of the fish sample (750 mg) with 600 µL of SUPRAS for five minutes, subsequent centrifugation for extract separation from matrix components and direct analysis of the extract after dilution 1:1 with methanol. Individual enantiomers of α-, ß- and γ-HBCD were separated on a chiral stationary phase of ß-cyclodextrin and quantified by monitoring of the [M-H](-)→Br(-) transition at m/z 640.9→80.9. Driving forces for the microextraction of HBCD in the SUPRAS involved both dispersion and dipole-dipole interactions. Quantitation limits for the determination of individual HBCD enantiomers in hake, cod, sole, panga, whiting and sea bass were within the intervals 0.5-3.4 ng g(-1), 0.9-2.5 ng g(-1), 0.6-1.4 ng g(-1), 1.0-5.6 ng g(-1), 0.8-1.3 ng g(-1) and 0.5-3.5 ng g(-1), respectively. Recoveries for fish samples fortified at the ng g(-1) level ranged between 87 and 114% with relative standard deviations from 1 to 10%. The sample treatment proposed greatly simplifies current procedures for extraction of HBCD stereoisomers and is a useful tool for the development of a large scale database for their presence in fish.

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BACKGROUND: The increased use of the quality of life (QOL) concept internationally suggests the need to evaluate its etic (universal) and emic (culture-bound) properties. This study replicated and expanded a previous cross-cultural study on QOL. METHOD: The three respondent groups (consumers, parents and professionals; total n = 781) were from four European countries: France, Belgium, Italy and Poland. The Cross Cultural Survey of Quality of Life Indicators was used to assess the importance and use of eight core dimensions of QOL. Two hypotheses were tested: (1) the etic properties would be demonstrated if there were similar profiles for the respondent and geographical groups, and if indicators grouped into the proposed QOL domains; and (2) the emic properties would be demonstrated if there were significant differences on scores across groups. RESULTS: Results supported both hypotheses. CONCLUSION: The present study replicated the findings of a large cross-cultural study that the QOL construct has both etic and emic properties.

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BACKGROUND: The Quality of Life Questionnaire (QOL-Q) is used widely to evaluate the quality of life of persons with intellectual disability (ID). Its validity for use with Spanish-speaking cultures has been demonstrated for individuals with visual disabilities, but not for those with physical or intellectual disabilities. Such was the purpose of the present study. METHOD: Two samples were administered the QOL-Q under standardized procedures. The first sample was composed of 209 Mexican participants with physical disabilities; the second was composed of 424 Spanish participants with ID. The hypothesis tested was: the applicability (i.e. etic properties) of the measure across countries and respondents would be demonstrated if reliability data and if factor composition were similar to the original measure. Cronbach's alpha was used to test reliability and exploratory factor analyses were used to test validity (i.e. factor structure). RESULTS: Data indicated that the reliability and factor structure was similar to that reported in the questionnaire's standardization manual and consistent with that reported in a number of Anglo-Saxon countries. CONCLUSION: The present study offers additional support for the valid use of the QOL-Q with Spanish-speaking populations.

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The purpose of this study is to improve supported employment programs analyzing the relationships between different variables involved in its development on job outcomes. One important variable is typicalness (understood as the degree to which the job of the person with a disability is similar in its different characteristics to that of co-workers without a disability). It also compares sheltered employment and supported employment in employment outcomes. The results showed more length of service in the job and salary for supported employment workers. As regards the developmental variables, time of external support, type of support, and adaptations are critical to get better outcomes. Finally, the need to finely balance the typicalness of the job and the characteristics of the worker involved is stressed.

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Different brands of commercial caffeinated and decaffeinated coffees (roasted, high roast, blend ground, and instant coffees) were studied. These coffees were tested for their ability to induce sister chromatid exchanges (SCE) in CHO-K1 cells. Tests were performed in the presence and in the absence of a metabolic activation system (S-9 mix). Results were compared to the roasting procedure because genotoxic products could be formed from these processes. Our results indicate that caffeinated instant coffees showed higher genotoxic activity than decaffeinated coffees. Non-significant genotoxic activity was detected with the green coffee (unroasted). The highest increase of the frequency of SCE occurred when the caffeinated instant coffee was tested in the absence of metabolic activation system. The repeatability of the test was checked through three assays with the same sample.

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The pyrethroid insecticide permethrin was tested for its ability to induce structural chromosome aberrations (CA) in human lymphocyte cultures and CHO cells, in order to confirm the clastogenic effect of itself and to compare the response of the two different cell types. Permethrin was tested in the range of 50-200 micrograms/ml in human lymphocyte cultures and in the range of 20-100 micrograms/ml in CHO cells. In both lymphocyte and CHO cultures, assays were performed in the absence and in the presence of a rat liver activation system (S9 mix). In the absence of S9 mix, two experiments with different duration of the treatment were carried out. Permethrin induced CA in both cultures when it was evaluated in the absence of a metabolic activation system. The activity of a given concentration of permethrin seemed to be decreased more by the reduction of the time of exposure than by the presence of S9 mix. Aberrations induced by permethrin were mainly chromosome-type aberrations in both cultures. Thus, permethrin can be characterised as an S-phase independent clastogenic agent. The response of both lymphocyte and CHO cultures was similar, indicating that both systems showed the same sensitivity for detecting the clastogenicity in vitro of permethrin.

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The pyrethroid insecticide permethrin was tested for its ability to induce sister chromatid exchanges (SCE), micronuclei (MN) and structural chromosome aberrations (CA) in cultured human peripheral blood lymphocytes. Permethrin was tested in the range of 5-500 micrograms/ml in the absence and in the presence of a rat liver activation system (S9 mix). Small elevations in the SCE frequencies were found and even though statistically significant may have no biological meaning, the more so since there was no dose-effect relationship. Permethrin induced both MN and CA when it was evaluated in the absence of a metabolic activation system. Nevertheless, it cannot be said that S9 mix suppressed the activity in itself. The effect of permethrin seemed to be time of exposure dependent. Permethrin could be characterized as a S-phase independent agent with greater potential for inducing chromosomal damage than sister chromatid exchanges.

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A synthetic pyrethroid insecticide, fenvalerate, was tested for its ability to induce chromosome aberrations (CA) and sister chromatid exchanges (SCE) in CHO cells. Fenvalerate was assayed both in the presence and in the absence of a rat liver activation system (S9-mix). Our results indicate that fenvalerate in the presence of S9-mix is able significantly to increase the frequency of CA, while in the SCE test this increase occurred both in the presence and in the absence of S9-mix. In addition, fenvalerate affected the cell cycle, causing a decrease in the mitotic index (MI) and in the proliferative rate index (PRI).

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