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Modern agricultural technology is based on a package that combines direct seeding and glyphosate with transgenic crops (soybean, maize, and cotton). Because of widespread glyphosate use, it is important to assess its impact on the environment. However, glyphosate's unique physicochemical characteristics make determination difficult at residue concentrations, especially in soils with high organic matter content, such as the soils from the central eastern region of Argentina, where strong analytical interferences are normally observed. The aim of this work was to compare the efficiency of two extraction methods of glyphosate using representative soils from Argentina. One method is based on the use of a phosphate buffer as the extracting solution and dichloromethane to minimize matrix organic content. The other method uses potassium hydroxide for the soil extraction of analytes and involves a cleanup step using solid phase extraction to minimize analytical interferences. Both methodologies involve a derivatization with 9-fluorenyl-methyl-chloroformate in borate buffer, the use of isotope labeled glyphosate as an internal standard, and detection based on ultrahigh-performance liquid chromatography coupled to tandem mass spectrometry. Recoveries obtained for soil samples spiked at 100 and 1000 μg kg−1were satisfactory in both methods (70%–120%). However, significant differences were observed in the effects on the organic matrix. The solid phase extraction cleanup step was insufficient to remove the interferences, whereas the dilution and the cleanup with dichloromethane were more effective in minimizing the ionic suppression.

Treatment of colorectal cancer (CRC) with monoclonal antibodies against epidermal growth factor receptor requires the assessment of the mutational status of exons 2, 3, and 4 of the NRASand KRASoncogenes. Moreover, the mutational status of exon 15 of the BRAFoncogene is a marker of poor prognosis in CRC. The Idylla NRAS-BRAF Mutation Test is a reliable, simple (<2 minutes hands-on time), and quick (<2 hours turnaround time) sample-to-result solution, enabling the detection of clinically relevant mutations in NRAS(18 mutations) and BRAF(5 mutations). A multicenter study was conducted in 14 centers using the Idylla NRAS-BRAF Mutation Test to assess the NRASand BRAFmutational status of 418 formalin-fixed, paraffin-embedded tissue samples from CRC patients. Results were compared with those obtained earlier by routine reference methods, including next-generation sequencing, pyrosequencing, mass spectrometry–based assays, PCR-based assays, and Sanger sequencing. In case of discordance, additional tests were performed by digital droplet PCR. Overall, after testing confirmation and excluding invalids/errors by design, concordances between the Idylla NRAS-BRAF Mutation Test and the reference test results were found in almost perfect agreement. In conclusion, the Idylla NRAS-BRAF Mutation Test enables the routine detection of all NRASand BRAFmutations deemed clinically relevant according to the latest clinical guidelines, without necessitating molecular expertise or infrastructure.

Modern agricultural technology is based on a package that combines direct seeding and glyphosate with transgenic crops (soybean, maize, and cotton). Because of widespread glyphosate use, it is important to assess its impact on the environment. However, glyphosate's unique physicochemical characteristics make determination difficult at residue concentrations, especially in soils with high organic matter content, such as the soils from the central eastern region of Argentina, where strong analytical interferences are normally observed. The aim of this work was to compare the efficiency of two extraction methods of glyphosate using representative soils from Argentina. One method is based on the use of a phosphate buffer as the extracting solution and dichloromethane to minimize matrix organic content. The other method uses potassium hydroxide for the soil extraction of analytes and involves a cleanup step using solid phase extraction to minimize analytical interferences. Both methodologies involve a derivatization with 9-fluorenyl-methyl-chloroformate in borate buffer, the use of isotope labeled glyphosate as an internal standard, and detection based on ultrahigh-performance liquid chromatography coupled to tandem mass spectrometry. Recoveries obtained for soil samples spiked at 100 and 1000 µg kg-1 were satisfactory in both methods (70%-120%). However, significant differences were observed in the effects on the organic matrix. The solid phase extraction cleanup step was insufficient to remove the interferences, whereas the dilution and the cleanup with dichloromethane were more effective in minimizing the ionic suppression. [ABSTRACT FROM AUTHOR]

A rapid analytical methodology has been developed for multi-residue determination of pesticides in soils using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) with a triple quadrupole analyzer. Soil samples were collected from 12 representative agricultural areas in Argentina, and 18 pesticides were selected on the basis of their use. Special attention was paid to minimize sample preparation, making easier the method application to routine analysis. Several extraction procedures were tested, performing a careful study on matrix effects. The method finally proposed (extraction with acetonitrile and a subsequent 2-fold dilution with water without any clean-up step) was fully validated at 0.05 and 0.5 mg kg−1on the basis of European SANCO 12571/2013 and 825/00 guidelines. The method applicability and robustness were demonstrated by analysis of quality control (QC) samples, consisting of eleven soils spiked at 0.5 mg kg−1. These soil samples were collected from different experimental plots, and were very diverse in their physico-chemical characteristics. The methodology developed is of easy application, there is low consumption of solvents and reagents, and no clean-up is required despite the complexity of the soil matrix. In the near future, the method developed will be used to monitor the presence of pesticides in large agricultural areas of Argentina.

Typology schemes are useful in partitioning natural spatial variability and thus helping implementing bioassessment methods. They have become widely accepted in Europe after the publication of the Water Framework Directive (WFD). The major objective of this study was to test if six Portuguese pre-defined physical stream-types (using System-B of the WFD) are concordant with macroinvertebrate assemblages collected in 31 undisturbed sites in a Portuguese river basin. A top-down (stream types defined by physical attributes) and a bottom-up approach (river classes defined by biological communities) were used. No significant differences were found in the mean number of taxa and abundance of different physical stream types and few taxa are characteristic of specific stream types. Discriminant analysis (DA) considering family-level composition revealed that all stream-types were significantly different and the cross-validation process showed that all stream-types had more than 50% of their samples correctly assigned. On the other hand, the bottom-up approach based on a correspondence analysis (CA) showed some overlap of the  macroinvertebrate communities of pre-defined stream types, indicating that variations in the macroinvertebrate community structure was primarily related to altitude, mineralisation and a temporal gradient. DA cross-validation and CA results suggest that tested stream types do not account for natural temporal changes known to affect macroinvertebrate communities in this Mediterranean basin and that the WFD typology should account for these natural variations. The exclusion of natural variability could indicate impairment when it does not exist or no impairment when it does exist (type I and II statistical errors).

A procedure for calibration of a spectral bandwidth standard for high-resolution spectrophotometers is described. Symmetrical absorption bands for a crystal standard are adopted. The method relies on spectral band shape fitting followed by a convolution with the slit function of the spectrophotometer. A reference spectrophotometer is used to calibrate the spectral bandwidth standard. Bandwidth calibration curves for a minimum spectral transmission factor relative to the spectral bandwidth of the reference spectrophotometer are derived for the absorption bands at the wavelength of the band absorption maximum. The family of these calibration curves characterizes the spectral bandwidth standard. We calibrate the spectral bandwidth of a spectrophotometer with respect to the reference spectrophotometer by determining the spectral transmission factor minimum at every calibrated absorption band of the bandwidth standard for the nominal instrument values of the spectral bandwidth. With reference to the standard spectral bandwidth calibration curves, the relation of the spectral bandwidth to the reference spectrophotometer is determined. We determine the discrepancy in the spectrophotometers’ spectral bandwidths by averaging the spectral bandwidth discrepancies relative to the standard calibrated values found at the absorption bands considered. A weighted average of the uncertainties is taken.

The application of excimer lasers in ablation, cleaning, and restoration for the recovery of paper and parchment manuscripts is a recently implemented technique. A report of the use of excimer lasers in a cleaning process by which mud was removed from Islamic papers and parchments is presented. It was found that, because of the close proximity of the binding energies of paper to paper and of paper to mud, it was difficult to maintain control of the ablation process. However, the substrate was not affected. Spectrocolorimetry was used as a technique to detect the effects of ablation on cleaned areas of the manuscripts in terms of change in color appearance and severity of aging postablation. The analysis was performed by comparison of treated and untreated areas. Mathematical modeling was developed to define a representative original color and a color-distribution parameter. Improvements in the measuring method were made to yield the required precision for evaluating differences in color produced by laser ablation and to follow the color evolution after ablation. Results show that the effects of restoration, aging, and the environmental conditions can be individually identified under certain conditions. The method has applications in other domains.

Sea urchin roe is a gastronomic delicacy appreciated worldwide and Portugal is the third largest consumer nation of seafood. However, sea urchin roe is recognized as a seafood by few members of the national coastal communities. Motivated by an increasing interest of gastronomic and aquaculture sectors in producing this seafood, a survey was conducted among the participants of gastronomic festivals aiming to characterize the motivations and preferences regarding sea urchin roe. The results showed that a high percentage of consumers would be willing to eat sea urchin roe in a restaurant, and approximately half of these were not motivated to buy it in the supermarket. The consumers willing to buy sea urchins in the supermarket, would buy it as the whole urchin or the chilled/frozen roe., even that it represents a challenge to households.In conclusion, sea urchin roe can be characterized as a high valued shellfish to be consumed in restaurants.

Presence of pesticides in drinking water is an issue of great concern in agricultural areas. In Argentina’s semiarid regions, where surface water sources are scarce and groundwater may be of poor quality, rainwater becomes important for safe water supply. The expansion of agriculture in these regions due to no till management has led to a high use of pesticides which jeopardize the safety of all water sources used for human consumption. The objective was to monitor the presence of pesticides in different water sources from two agricultural areas of Santiago del Estero. Samples belonged to cisterns in which rainwater is collected, wells and dams. The most contaminated sources were dams, followed by cisterns and wells. Applied doses and frequency of use played an important role in the presence of pesticides. Thus, the most frequent molecules were mainly herbicides; atrazine and metolachlor were the most abundant. Glyphosate and aminomethylphosphonic acid presented the highest concentrations. Almost all measured values were below the US Environmental Protection Agency limits, but 73% of the samples exceeded the limit of 0.5 μg L−1established by the European Union for the sum of molecules although only 7.4% of individual molecules exceeded the limit of 0.1 μg L−1. However, risk assessment showed that pesticides from all sources presented a low potential risk to human health through drinking water exposure route.