41 research outputs found

    Non-trilinear chromatographic time retention-fluorescence emission data coupled to chemometric algorithms for the simultaneous determination of 10 polycyclic aromatic hydrocarbons in the presence of interferences

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    Multivariate calibration coupled to high-performance liquid chromatography-fast scanning fluorescence spectroscopy (HPLC-FSFS) was employed for the analysis of 10 selected polycyclic aromatic hydrocarbons (PAHs), six of which correspond to heavy PAHs. The goal of the present study was the successful resolution of a system even in the presence of real interferences. Second-order HPLC-FSFS data matrices were obtained in a short time with a chromatographic system operating in isocratic mode. The difficulties in aligning chromatographic bands in complex systems, such as the ones presented here, are discussed. Two second-order calibration algorithms which do not require chromatographic alignment were selected for data processing, namely, multivariate curve resolution-alternating least-squares (MCR-ALS) and parallel factor analysis 2 (PARAFAC2). These algorithms did also achieve the second-order advantage, and therefore they were able to overcome the problem of the presence of unexpected interferences. The study was employed for the discussion of the scopes of the applied second-order chemometric tools, demonstrating the superiority of MCRALS to successfully resolve this complex system. The quality of the proposed techniques was assessed on the basis of the analytical recoveries from different types of water and olive oil samples after solid-phase extraction. The studied concentration ranges in water samples were 5.6 × 10-3-0.20 ng mL-1 for heavy PAHs and 0.036-0.80 ng mL-1 for light PAHs, while in oil samples the PAHs concentrations were 0.13-9.6 and 2.3-49.5 ng mL-1 for heavy and light PAHS, respectively. All real samples were analyzed in the presence of the studied interferences.Fil: Bortolato, Santiago Andres. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Rosario. Instituto de QuĂ­mica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de QuĂ­mica Rosario; ArgentinaFil: Arancibia, Juan Alberto. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Rosario. Instituto de QuĂ­mica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de QuĂ­mica Rosario; ArgentinaFil: Escandar, Graciela Monica. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Rosario. Instituto de QuĂ­mica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de QuĂ­mica Rosario; Argentin

    Scope of partial least-squares regression applied to the enantiomeric composition determination of ketoprofen from strongly overlapped chromatographic profiles

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    Valuable quantitative information could be obtained from strongly overlapped chromatographic profiles of two enantiomers by using proper chemometric methods. Complete separation profiles where the peaks are fully resolved are difficult to achieve in chiral separation methods, and this becomes a particularly severe problem in case that the analyst need to measure the chiral purity, i.e., when one of the enantiomers is present in the sample in very low concentrations. In this report, we explore the scope of a multivariate chemometric technique based on unfolded partial least-squares regression, as a mathematical tool to solve this quite frequent difficulty. This technique was applied to obtain quantitative results from partially overlapped chromatographic profiles of R- and S-ketoprofen, with different values of enantioresolution factors (from 0.81 down to less than 0.2 resolution units), and also at several different S:R enantiomeric ratios. Enantiomeric purity below 1% was determined with excellent precision even from almost completely overlapped signals. All these assays were tested on the most demanding condition, i.e., when the minor peak elutes immediately after the main peak. The results were validated using univariate calibration of completely resolved profiles and the method applied to the determination of enantiomeric purity of commercial pharmaceuticals.Laboratorio de InvestigaciĂłn y Desarrollo de MĂ©todos AnalĂ­ticos (LIDMA

    Trabajo, empleo, calificaciones profesionales, relaciones de trabajo e identidades laborales. Vol. I

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    CLACSO ha apoyado desde sus inicios la constituciĂłn y desarrollo de grupos de reflexiĂłn centrados en la problemĂĄtica del mundo del trabajo. Los temas abordados sucesivamente han sido el empleo y el desempleo, los movimientos laborales, las relaciones de trabajo, las condiciones y medio ambiente de trabajo. Las reuniones y seminarios se han desarrollado en las principales ciudades del continente: MĂ©xico DF, La Habana, MedellĂ­n, Santiago de Chile, RĂ­o de Janeiro, San Pablo, Buenos Aires y Montevideo. Los objetivos son facilitar los encuentros, el debate y las acciones de cooperaciĂłn entre los especialistas mas reconocidos y con los jĂłvenes investigadores, becarios, maestrandos y doctorandos y nutrir una comunidad muy diversa, y pluralista de cientĂ­ficos sociales que no han cesado de crecer. Los grupos han reunido a destacados especialistas de la casi totalidad de paĂ­ses de la regiĂłn, con una composiciĂłn multidisciplinaria y pluralista que abarca a sociĂłlogos del trabajo y de la educaciĂłn, cientistas polĂ­ticos, economĂ­stas del trabajo y del desarrollo, abogados laboralistas y psicĂłlogos del trabajo, entre otras. Sus estudios han dado lugar a numerosas publicaciones editadas por CLACSO, la UAM, el PREALC de la OIT, el CEIL PIETTE del CONICET y Trabajo y Sociedad de Argentina, y forman parte de las bibliografĂ­as de aquellas disciplinas. Desde 2007 se constituyĂł el actual grupo "Trabajo, empleo, calificaciones profesionales, relaciones de trabajo e identidades laborales" con sede en la UNAM, sede Iztapalapa y en el CEIL-PIETTE del CONICET. Los dos volĂșmenes que ofrecemos a la comunidad acadĂ©mica y a los actores sociales contienen la mayorĂ­a de las ponencias presentadas en el Seminario de Buenos Aires, realizado en noviembre de 2007.INDICE PresentaciĂłn del Grupo de Trabajo: Trabajo, empleo, calificaciones profesionales, relaciones de trabajo e identidades laborales Julio CĂ©sar Neffa y Enrique de la Garza Toledo 11 PresentaciĂłn de la obra: Nuevos y viejos escenarios en el mundo laboral latinoamericano: distintas miradas para su estudio Leticia Muñiz Terra 15 Primera parte Dimensiones teĂłricas y metodolĂłgicas Diez tesis sobre el trabajo del presente (y el futuro del trabajo) Ricardo Antunes 29 Aportes a una teorĂ­a del cambio: gubernamentalidad, fuerzas productivas y praxis de sujetos colectivos en nueva Ă©poca Alberto L. Bialakowsky, MarĂ­a Ignacia Costa y M. Mercedes Patrouilleau 45 um ensaio sobre inĂ©rcia social Adalberto Cardoso 83 Hacia un concepto ampliado de trabajo Enrique de la Garza Toledo 111 Comentarios: Del trabajo esclavo a las nuevas formas de esclavitud en el trabajo Irene Vasilachis de Gialdino 141 Segunda parte Trabajo, identidad y subjetividad Cuando el trabajo informal es espacio para la construcciĂłn de identificaciones colectivas. Un estudio sobre ferias comerciales urbanas Mariana Busso 159 ConstrucciĂłn del sujeto de trabajo en la condiciĂłn de precariedad Karina Arellano, Diego Baccarelli, Cecilia Dallacia, LucĂ­a De Gennaro, Soraya Giradles y Emilio Sadier 193 Comentarios: Comentarios crĂ­ticos de las ponencias presentadas en la Mesa Trabajo, identidad y subjetividad Juan Montes CatĂł 203 Tercera parte EducaciĂłn, calificaciĂłn profesional, productividad y salarios Fuentes de la valorizaciĂłn del capital: la relaciĂłn entre productividad y salarios. Argentina 1993-2006 Javier Lindenboim, Juan M. Graña y DamiĂĄn Kennedy 215 Demandas empresariales en las estrategias de formaciĂłn de los ingenieros en dos zonas argentinas Marta Panaia 243 Saberes, intervenciones profesionales y clasificaciones profesionales: nuevos requerimientos a idĂłneos, tĂ©cnicos e ingenieros Julio Testa; Claudia Figari y MartĂ­n Spinosa 275 Pautas de desigualdad en el mundo social productivo uruguayo. Aportes para el debate en torno a la gestiĂłn por competencias Mariela Quiñones Montoro 309 Cuarta parte La nueva dinĂĄmica empresarial. InnovaciĂłn y flexibilizaciĂłn en la industria Trabajo de organizaciĂłn y cadenas de valor. El caso de la vestimenta uruguaya Marcos Supervielle y Emiliano Rojido 337 Potencialidades y limitaciones de sectores dinĂĄmicos de alto valor agregado: la industria aeroespacial en MĂ©xico, Jorge Carrillo y Alfredo Hualde 373 La industria del salmĂłn en Chile: Âżcrecimiento social o explotaciĂłn laboral?, Antonio Aravena 397 Rasgos posfordistas en el paisaje laboral de la gran industria del Valle del Cauca colombiano Carlos MejĂ­a Sanabria 42

    El "retorno de lo reprimido": el papel de la sexualidad en la recepción del psicoanålisis en el círculo médico chileno, 1910-1940

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    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

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    Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≀0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

    Second-order chromatographic photochemically induced fluorescence emission data coupled to chemometric analysis for the simultaneous determination of urea herbicides in the presence of matrix co-eluting compounds

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    This paper presents a novel approach for the simultaneous determination of isoproturon, rimsulfuron and monuron, three widely used urea-derivative herbicides, in interfering environmental samples, combining the advantages of photoinduced fluorescence (PIF) emission, liquid chromatography and second-order chemometric algorithms. Chromatographic detection is performed with a fast-scanning spectrofluorimeter, which allowed efficient collection of PIF through a post-column photoreactor. Thus, second-order elution time-PIF emission data matrices are rapidly obtained (in less than 4 min) using a chromatographic system operating in an isocratic regime using a minimal amount of organic solvent. The goal of the present study was the successful resolution of a system in the presence of foreign compounds which can be present in real samples. The study was employed for the discussion of the scope of the applied second-order algorithms selected for data processing, namely parallel factor analysis (PARAFAC), multivariate curve resolution-alternating least-squares (MCR-ALS), and multidimensional and unfolded partial least-squares coupled to residual bilinearization (N- and U-PLS/RBL). U-PLS/RBL showed the best performance to quantify the herbicides, even when the foreign compounds showed very similar spectral and time profiles to the analytes. The quality of the proposed technique was assessed on the basis of the analytical recoveries from different types of water samples spiked with analytes and other selected agrochemicals. After solid-phase extraction, reaching a preconcentration factor of 50, detection limits of 2.9, 2.4, and 1.7 ng mL−1 for isoproturon, rimsulfuron, and monuron, respectively, were obtained in those interfering matrices, with relative prediction errors lower than 5%.Fil: Arancibia, Juan Alberto. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de QuĂ­mica Rosario (IQUIR-CONICET); Argentina.Fil: Escandar, Graciela MĂłnica. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de QuĂ­mica Rosario (IQUIR-CONICET); Argentina

    A green-analytical chemistry method for agrochemical-residue analysis in vegetables

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    Ten agrochemicals, including fungicides, insecticides, herbicides and a plant growth regulator, were quantified at part per billion levels in complex matrices using a green-analytical chemistry (GAC) method. Liquid chromatography with dual UV/diode array (DAD) and fluorescence (FLD) detections was carried out in a single run, and the second-order DAD-elution time and FLD-elution time data obtained were treated with MCR-ALS (multivariate curve resolution/alternating least-squares) algorithm. In this way, while analytes are measured through their more appropriate (absorbance and/or fluorescence) signals, chemometric treatment of the corresponding matrices allows the resolution of total or partial overlapped bands, and to overcome the presence of interferences in real samples. In this work, FLD-elution time second-order data were obtained for the first time at two excitation wavelengths, improving the sensitivity of fluorescent analytes. The approach was successfully applied to in land cultivated vegetables, including mushroom, lettuce, alfalfa sprout, cucumber, and celery.Fil: Carabajal, Maira Daniela. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario (IQUIR-CONICET); Argentina.Fil: Arancibia, Juan Alberto. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario (IQUIR-CONICET); Argentina.Fil: Escandar, Graciela Mónica. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario (IQUIR-CONICET); Argentina

    Excitation-emission fluorescence-kinetic data obtained by Fenton degradation. Determination of heavy-polycyclic aromatic hydrocarbons by four-way parallel factor analysis

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    For the first time, a simple and environmentally friendly third-order/four-way calibration was applied for the simultaneous determination of five heavy-polycyclic aromatic hydrocarbons (PAHs) in interfering environments. The kinetic evolution of the Fenton degradation of benzo[a]pyrene, dibenz[a,h]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene and benz[a]anthracene was followed by recording full excitation-emission fluorescence matrices (EEFMs) of the samples at different reaction times, obtaining third-order EEFM-kinetic (EEFM-K) data. The sensitivity of the method was increased by carrying out the reaction in the presence of methyl-ÎČ-cyclodextrin. The four-way parallel factor (PARAFAC) algorithm, which was used for data processing, exploits the second-order advantage, allowing analyte concentrations to be estimated even in the presence of an uncalibrated fluorescent background. The clear superiority of the applied approach in comparison with second-order/three-way calibration performed with unreacting EEFMs is demonstrated, using two sets of samples with foreign compounds with particular spectral profiles. In one of the latter sets, the existence of a third-order advantage was explored and discussed. The feasibility to directly determine parts-per-trillion concentration levels of PAHs after a very simple solid-phase extraction with C18 membranes is established with natural water samples containing uncalibrated constituents.Fil: Carabajal, Maira Daniela. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de QuĂ­mica Rosario (IQUIR-CONICET); Argentina.Fil: Arancibia, Juan Alberto. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de QuĂ­mica Rosario (IQUIR-CONICET); Argentina.Fil: Escandar, Graciela MĂłnica. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de QuĂ­mica Rosario (IQUIR-CONICET); Argentina

    Chemometrics-assisted liquid chromatographic determination of quinolones in edible animal tissues

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    A chemometric technique applied to chromatographic-spectral data allowed the quantification of ten different quinolones in edible animal tissues such as chicken and bovine liver and bovine kidney. The employed strategy proved to be excellent for the analysis of quinolones when complete analyte separation is difficult or requires long analysis times. In addition, the target signals suffer interference from the complex background matrices, which can be resolved by the data processing tools. The analysis was carried out applying multivariate curve resolution coupled to alternating least-squares (MCR-ALS). The latter allowed the chromatographic determinations to be performed under isocratic conditions in less than 5 min. Under these experimental conditions, appropriate figures of merit such as selectivity (0.08–0.8) and sensitivity (400–23000 fluorescence intensity units L mg−1) were achieved. Furthermore, the average relative prediction errors (4–12%) and detection limits (7–125 ÎŒg Kg−1) permitted the determination of quinolones at concentrations which are below the corresponding maximum residue limits permitted.Fil: Anzardi, Maria Betania. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Rosario. Instituto de QuĂ­mica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de QuĂ­mica Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas; ArgentinaFil: Arancibia, Juan Alberto. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Rosario. Instituto de QuĂ­mica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de QuĂ­mica Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas; Argentin

    Multivariate curve resolution applied to kinetic-spectroscopic data matrices: Dye determination in foods by means of enzymatic oxidation

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    In this work, the combination of chemometric techniques with kinetic-spectroscopic data allowed quantifying two dyes (tartrazine and carminic acid) in complex matrices as mustard, ketchup, asparagus soup powder, pumpkin soup powder, plum jam and orange-strawberry juice. Quantitative analysis was performed without the use of tedious sample pretreatment, due to the achievement of the second-order advantage. The results obtained showed an improvement in simplicity, speed and cost with respect to usual separation techniques, allowing to properly quantifying these dyes obtaining limits of detection below 0.6 mg L−1. In addition, to the best of our knowledge, is the first time that kinetic-spectroscopic data are obtained from the action of laccase for analytical purposes.Fil: Boeris, Valeria. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Rosario. Instituto de QuĂ­mica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de QuĂ­mica Rosario; ArgentinaFil: Arancibia, Juan Alberto. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Rosario. Instituto de QuĂ­mica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de QuĂ­mica Rosario; ArgentinaFil: Olivieri, Alejandro Cesar. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Rosario. Instituto de QuĂ­mica Rosario. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de QuĂ­mica Rosario; Argentin
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