Dimethylglyoxime modified screen-printed electrodes for nickel determination

This work reports the development of a dimethylglyoxime (DMG) modified sensor in which the complexing agent was successfully immobilized by drop-casting onto a screen-printed carbon electrode support (SPCE). The experimental conditions for the preparation of the DMG-SPCE sensor were optimized by means of a D-optimal design, and the built sensors were analytically evaluated for the determination of Ni(II) by adsorptive stripping voltammetry (AdSV). Its analytical performance suggests its suitability for the determination of Ni(II)-ions by AdSV at concentration levels of μg L-1 (LOD of 2.3 μg L-1, linear range from 7.6 to 200 μg L-1). Finally, the applicability of the developed sensor was assessed by the determination of trace levels of Ni(II) by AdSV in a wastewater reference material with a very high reproducibility (0.005 %) and good trueness (0.1 %)

Norovirus outbreaks in long-term care facilities in Catalonia from 2017 to 2018

Norovirus is the leading cause of outbreaks of acute viral gastroenteritis. We carried out this study to investigate outbreaks in long-term care facilities reported in 2017 and 2018 in Catalonia (Spain). The characteristics of the centers, exposed persons and the genogroups responsible were analyzed. Viral loads were estimated. The attack rate (AR) of the outbreaks studied, and the rate ratio (RR) and the odds ratio (OR) and their 95% confdence intervals as measures of association were calculated. The mean cycle thresholds were compared using the t-test for independent means. We included 30 outbreaks (4631 exposed people). The global AR was 25.93%. The RR of residents vs. staf was 2.28 (95% CI 2.0-2.6). The RR between AR in residents with total or severe dependence vs. residents with moderate, low or no-dependence was 1.23 (95% CI 1.05-1.45). The AR were higher in smaller centers than in larger ones (38.47% vs. 19.25% and RR 2; 95% CI 1.82-2.2). GII was responsible for 70% of outbreaks. No association was found between the genogroup and presenting symptoms (OR 0.96; 95% CI 0.41-2.26). Viral loads were higher in symptomatic than in asymptomatic patients (p = 0.001)

Determination of HPLC-UV fingerprints of Spanish paprika (Capsicum annuum L.) for its classification by linear discriminant analysis

The development of a simple HPLC-UV method towards the evaluation of Spanish paprika' phenolic profile and their discrimination based on the former is reported herein. The approach is based on C18 reversed-phase chromatography to generate characteristic fingerprints, in combination with linear discriminant analysis (LDA) to achieve their classification. To this aim, chromatographic conditions were optimized so as to achieve the separation of major phenolic compounds already identified in paprika. Paprika samples were subjected to a sample extraction stage by sonication and centrifugation; extracting procedure and conditions were optimized to maximize the generation of enough discriminant fingerprints. Finally, chromatograms were baseline corrected, compressed employing fast Fourier transform (FFT), and then analyzed by means of principal component analysis (PCA) and LDA to carry out the classification of paprika samples. Under the developed procedure, a total of 96 paprika samples were analyzed, achieving a classification rate of 100% for the test subset (n=25)

Involvement of workers in closed and semiclosed institutions in outbreaks of acute gastroenteritis due to norovirus

Norovirus outbreaks frequently occur in closed or semiclosed institutions. Recent studiesin Catalonia and various countries indicate that, during outbreaks in these institutions, norovirus isdetected in between 23% and 60% of workers, and the prevalence of infection in asymptomatic workersinvolved in outbreaks ranges from 17% to 40%. In this work, we carried out a prospective studyto investigate the involvement of workers in closed and semiclosed institutions during outbreaks.The attack rates (ARs) and the rate ratios (RRs) were calculated according to the type of transmissionand occupational category. The RRs and 95% confidence intervals (CIs) between workers and userswere calculated. The mean cycle of quantification (Cq) values were compared according to thegenogroup and the presence of symptoms. ARs were higher in person-to-person transmission thanin common vehicle outbreaks, and 38.8% of workers were symptomatic. The RR between workersand users was 0.46 (95% CI 0.41-0.52). The ARs in workers were high, particularly in workers withcloser contact with users. The mean Cq was lower in patients than in asymptomatic infected persons,although the difference was only significant for genogroup I (GI). The frequency of asymptomaticinfected persons suggests that personal hygiene measures should be followed by all workers in thecenters affected

Determination of HPLC-UV fingerprints of Spanish paprika (Capsicum annuum L.) for its classification by linear discriminant analysis

The development of a simple HPLC-UV method towards the evaluation of Spanish paprika' phenolic profile and their discrimination based on the former is reported herein. The approach is based on C18 reversed-phase chromatography to generate characteristic fingerprints, in combination with linear discriminant analysis (LDA) to achieve their classification. To this aim, chromatographic conditions were optimized so as to achieve the separation of major phenolic compounds already identified in paprika. Paprika samples were subjected to a sample extraction stage by sonication and centrifugation; extracting procedure and conditions were optimized to maximize the generation of enough discriminant fingerprints. Finally, chromatograms were baseline corrected, compressed employing fast Fourier transform (FFT), and then analyzed by means of principal component analysis (PCA) and LDA to carry out the classification of paprika samples. Under the developed procedure, a total of 96 paprika samples were analyzed, achieving a classification rate of 100% for the test subset (n=25)