Sensitizing Chemicals

[Resumo] Estudo e análise das enfermidades profesionais causadas por axentes químicos sensibilizantes. Clasificación dos axentes químicos sensibilizantes e dos seus análogos en función dos efectos que producen.[Abstract] Study and analysis of professional diseases caused by sensitizing chemicals. Classification of sensitizing chemicals and their analogist in terms of the effects they produce

Classification of Nickel Compounds by their Carcinogenic and Mutagenic Properties in accordance with Directives 2008/58/EC and 2009/2/EC

[Resumo] Análise das directivas 2008/58/CE e 2009/2/CE, nas cales se aborda a clasificación dos compostos de níquel –con numerosas aplicacións de uso cotián– en canceríxenos e mutáxenos, desde o punto de vista da base científica en que se fundamenta. Inténtase, así mesmo, clarificar esta clasificación comparándoa con outras establecidas por outras normativas e diferentes asociacións profesionais internacionais.[Abstract] Analysis of Directives 2008/58/EC and 2009/2/EC with respect to the classification of nickel compounds in carcinogens and mutagens and comparison with other classifications published for other international institutions

Mononuclear/Binuclear [VIVO]/[VVO2] Complexes Derived from 1,3-Diaminoguanidine and Their Catalytic Application for the Oxidation of Benzoin via Oxygen Atom Transfer

[Abstract] Ligands H4sal-dag (I) and H4Brsal-dag (II) derived from 1,3-diaminoguanidine and salicylaldehyde or 5-bromosalicylaldehyde react with one or 2 mol equivalent of vanadium precursor to give two different series of vanadium complexes. Thus, complexes [VIVO(H2sal-dag) (H2O)] (1) and [VIVO(H2Brsal-dag) (H2O)] (2) were isolated by the reaction of an equimolar ratio of these ligands with [VIVO(acac)2] in MeOH. In the presence of K+/Cs+ ion and using aerially oxidized [VIVO(acac)2], the above reaction gave complexes [K(H2O){VVO2(H2sal-dag)}]2 (3), [Cs(H2O){VVO2(H2sal-dag)}]2 (4), [K(H2O){VO2(H2Brsal-dag)}]2 (5), and [Cs(H2O){VVO2(H2Brsal-dag)}]2 (6), which could also be isolated by direct aerial oxidation of complexes 1 and 2 in MeOH in the presence of K+/Cs+ ion. Complexes [(H2O)VIVO(Hsal-dag)VVO2] (7) and [(H2O)VIVO(HBrsal-dag)VVO2] (8) were isolated upon increasing the ligand-to-vanadium precursor molar ratio to 1:2 under an air atmosphere. When I and II were reacted with aerially oxidized [VIVO(acac)2] in a 1:2 molar ratio in MeOH in the presence of K+/Cs+ ion, they formed [K(H2O)5{(VVO2)2(Hsal-dag)}]2 (9), [Cs(H2O)2{(VVO2)2(Hsal-dag)}]2 (10), [K2(H2O)4{(VVO2)2(Brsal-dag)}]2 (11), and [Cs2(H2O)4{(VVO2)2(Brsal-dag)}]2 (12). The structures of complexes 3, 4, 5, and 9 determined by single-crystal X-ray diffraction study confirm the mono-, bi-, tri-, and tetra-anionic behaviors of the ligands. All complexes were found to be an effective catalyst for the oxidation of benzoin to benzil via oxygen atom transfer (OAT) between DMSO and benzoin. Under aerobic condition, this oxidation also proceeds effectively in the absence of DMSO. Electron paramagnetic resonance and 51V NMR studies demonstrated the active role of a stable V(IV) intermediate during OAT between DMSO and benzoin.M.R.M. thanks the Science and Engineering Research Board (SERB), Department of Science and Technology, New Delhi, India for the financial support (grant no. CRG/2018/000182)Government of India. Science and Engineering Research Board; CRG/2018/00018

Polymer-Supported Oxidovanadium(IV) Complexes and Their Catalytic Applications in One-Pot Multicomponent Reactions Producing Biologically Active 2,4,5-Trisubstituted-1H-imidazoles

This article belongs to the Special Issue Multicomponent Catalytic Reactions under Green Conditions[Abstract] Two new monobasic tridentate O⁀N⁀N donor ligands, HL1 (I) and HL2 (II) have been obtained in two steps by reacting phenylhydrazine and salicylaldehyde or 3,5-di-tert-butylsalicylaldehyde and then reacting the resulting compounds with 2-chloromethylbenzimidazole in the presence of triethylamine. The reaction of [VIVO(acac)2] with these ligands in a 1:1 molar ratio in dry methanol led to the formation of homogeneous oxidovanadium(IV) complexes [VIVO(acac)L1] (1) and [VIVO(acac)L2] (2). Immobilization of these complexes on chloromethylated polystyrene (PS-Cl) cross-linked with divinyl benzene resulted in corresponding polymer-supported heterogeneous complexes PS-[VIVO(acac)L1] (3) and PS-[VIVO(acac)L2] (4). Ligands (I and II), homogeneous complexes (1 and 2) and heterogeneous complexes (3 and 4) have been characterized using elemental analysis and various spectroscopic techniques. A single crystal X-ray diffraction study of I and 1 further confirms their structures. The oxidation state IV of vanadium in these complexes was assured by recording their EPR spectra while heterogeneous complexes were further characterized using field emission-scanning electron microscopy (FE-SEM) combined with energy dispersive X-ray analysis (EDS) and atomic force microscopy (AFM). All vanadium complexes have been explored for their catalytic potential to one-pot-three-component reactions (reagents: benzil, ammonium acetate and various aromatic aldehydes) for the efficient synthesis of 2,4,5-triphenyl-1H-imidazole derivatives (nine examples). Various reaction conditions have been optimized to obtain a maximum yield (up to 96%) of catalytic products. It has been found that heterogeneous complexes show excellent catalytic activity and are recyclable up to five catalytic cycles.This research was funded by the Science and Engineering Research Council (CRG/2018/000182), the Department of Science and Technology, New Delhi, the Government of IndiaIndia. Science and Engineering Research Council; CRG/2018/00018

Wind erosion and PM10 emission in two agricultural soils of La Pampa Province, Argentina

El objetivo de este estudio fue evaluar la erosión eólica y la emisión de partículas finas (PM10) en dos suelos agrícolas de textura Franca (F) y Arenosa franca (AF) respectivamente. Se realizaron mediciones durante dos años consecutivos sobre dos parcelas experimentales de 80x 200m ubicadas en sentido norte-sur. El transporte horizontal de masa promedio (Q) en el suelo F (6,95E-05 kg m-2 s-1) fue mayor que en el AF (4,19E-06 kg m-2 s-1), posiblemente debido a las mayores velocidades de viento en F y a la mayor cobertura vegetal en AF. En F,Q aumentó de forma lineal con la distancia, mientras que en AF se estabilizó entre los 100 y 150m, indicando que en suelos de textura fina el máximo Q puede alcanzarse a una distancia mayor que en suelos de textura más gruesa. La emisión de PM10 fue mayor en F (5,05E-09 kg m-2 s-1) que en AF (6,64E-10 kg m-2 s-1), debido por un lado al alto Q ocurrido en F y, por el otro, a la diferente composición del material transportado por saltación, compuesto predominantemente por agregados de partículas finas en el suelo de textura más fina (F) que se fragmentan progresivamente emitiendo PM10. Por el contrario, en el suelo de textura más gruesa (AF) el material de saltación está compuesto predominantemente por partículas individuales que se fragmentan en menor medida. Esto causó que la eficiencia de emisión fuera mayor en F en todas las tormentas. Sin embargo, este parámetro mostró cambios en función de las condiciones meteorológicas (velocidad media del viento) y edáficas (distribución del tamaño de agregados superficiales) predominantes durante cada evento erosivo, inclusive en el mismo suelo.The objective of this study was to evaluate the wind erosion and emission of fine particles (PM10) on two agricultural soils: a loam soil (F) and sandy loam soil (AF). Measurements were made during two consecutive years at two experimental plots of 80 x 200m oriented north-south. The horizontal mass transport (Q) and the PM10 emission were quantified. The average Q in F (6.955E-05 kg m-2 s-1) was higher than in AF (4.19E-06 kg m-2 s-1) due to the higher wind speeds and lower vegetation cover in F. In F the mass transport increased linearly with distance, while in AF it stabilized between 100 and 150m, indicating that on fine-textured soils the maximum Q could be reached at greater distances than at coarser textured soils. The PM10 emission was higher in F (5.05E09 kg m-2 s-1) than in AF (6.64E-10 kg m-2 s-1), probably on one hand due to the high Q occurred in F and on the other hand, to the different composition of the material transported by saltation, composed predominantly by aggregated fine particles that were progressively fragmented, emitting PM10. On the contrary, in AF the material transported by saltation is predominantly composed of individual particles that are fragmented to a lesser extent. For this reason, the emission efficiency was also higher in F for all the wind-erosion events. However, we found that this parameter changes depending on the weather (average wind speed) and soil conditions (aggregates size distribution of topsoil) that prevail during each erosive event, even on the same soil.Fil: Avecilla, Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Panebianco, Juan Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Buschiazzo, Daniel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentin

Professional Illnesses Related with the Asbestos Exposure

[Resumo] Neste traballo realizamos un estudo das doenzas causadas pola introdución do amianto no corpo humano, con dous obxectivos: por unha banda, aclarar cales son consideradas enfermidades profesionais en España, do elenco de enfermidades relacionadas co amianto; e, pola outra, concienciar do perigo que representa para a saúde a exposición ao amianto, dado que as patoloxías que produce se manifestan despois dun longo período de latencia.[Abstract] In this work we conduct a study of the diseases caused by the introduction of asbestos on the human body, with two objectives: first, to clarify what are considered occupational diseases in Spain, specifically the range of asbestos-related ones; and secondly, to raise awareness of the danger that represents health exposure to asbestos, since the diseases manifest after a long latency period

Análisis comparativo de dos técnicas para evaluar la capacidad de retención de agua en Chuquiraga erinacea Don.

Rainfall interception is a process scarcely studied in arid and semiarid environments. The aim of this study was comparatively analyze two field techniques to evaluate the water storage capacity in Chuquiraga erinacea Don., characteristic shrub species of the CaldenalMonte Occidental ecotone region, Argentina The study was conducted in the annexed field of INTA in Chacharramendi, La Pampa. Water storage capacity was measured on whole plants from two techniques on field: rainfall simulation and immersion. Water storage capacity, expressed in percentage of biomass was determined by difference wet weight fresh weight. Equality of results from field techniques for whole plants of Chuquiraga erinacea justified the application of immersion method in the study to be more expeditious implementation and more economical in terms of time and costs.La intercepción de lluvia es un proceso escasamente estudiado en ambientes áridos y semiáridos. El objetivo de este estudio fue analizar comparativamente dos técnicas de campo para evaluar la capacidad de retención de agua en Chuquiraga erinacea Don., especie arbustiva característica de la región del ecotono Caldenal Monte Occidental, Argentina. El estudio se realizó en el Campo Anexo de INTA en Chacharramendi, La Pampa, Argentina. Se midió capacidad de retención de agua sobre plantas enteras a partir de dos técnicas: simulación de lluvia e inmersión. La capacidad de retención de agua, expresado en porcentaje respecto de la biomasa verde, se determinó por diferencia peso mojado – peso fresco. A partir de un análisis de ANCOVA se determinó la igualdad de resultados de ambas técnicas, justificando la aplicación de inmersión por ser más expeditiva y económica en términos de tiempo y costos

Design and Development of Small-Molecule Arylaldoxime/5-Nitroimidazole Hybrids as Potent Inhibitors of MARK4: a Promising Approach for Target-Based Cancer Therapy

[Abstract] Microtubule affinity-regulating kinase 4 (MARK4), a member of the serine/threonine kinase family, is an emerging therapeutic target in anticancer drug discovery paradigm due to its involvement in regulation of microtubule dynamics, cell cycle regulation, and cancer progression. Therefore, to identify the novel chemical architecture for the design and development of novel MARK4 inhibitors with concomitant radical scavenging property, a series of small-molecule arylaldoxime/5-nitroimidazole conjugates were designed and synthesized via multistep chemical reactions following the pharmacophoric hybridization approach. Compound 4h was identified as a promising MARK4 inhibitor with high selectivity toward MARK4 inhibition as compared to the panel of screened 30 kinases pertaining to the serine/threonine family, which was validated by molecular docking and fluorescence binding studies. The comprehensive cell-based examination divulged the promising apoptotic, antiproliferative, and antioxidant potential for the chemotype 4h. The compound 4h was endowed with the Ka value of 3.6 × 103 M–1 for human serum albumin, which reflects its remarkable transportation and delivery properties to the target site via blood. The present study impedes that in the future, such compounds may stand as optimized pharmacological lead candidates in drug discovery for targeting cancer via MARK4 inhibition with a remarkable anticancer profile.Council of Scientific and Industrial Research (India); 09/466 (0220) 2K19 EMR-IGovernment of India; EMR/2015/002372Government of India; BT/PR12828/AAQ/1/622/2015Indian Council of Medical Research; 45/9/2019-PHA/BM

Desing of a portable wind tunnel for the wind erosion study

La erosión eólica (EE) es un proceso de degradación irreversible de suelos de regiones áridas y semiáridas. Con el uso de túneles de viento portátiles es posible simular la EE controlando variables críticas como la velocidad y dirección del viento, la duración de los eventos erosivos; además de parámetros del suelo en condiciones naturales como los niveles de humedad, rugosidad y cobertura. Los objetivos de este trabajo fueron: 1) describir los principales aspectos del diseño y la operación de un túnel de viento portátil para estudios de erosión eólica, y 2) Calibrar el túnel para cumplir con los criterios aerodinámicos relacionados con el desarrollo de un perfil vertical de viento y de distribución de material erosionado similares a las condiciones naturales. Los principales componentes del túnel son: chasis, motor, hélice, sección curva, placa cribada y las secciones del túnel propiamente dicho. Cada una de estas secciones tiene 2 m de largo; 0,5 m de ancho y 1 m de alto. El túnel fue calibrado en un Haplustol Éntico con una superficie lisa y sin cobertura vegetal. La velocidad máxima alcanzada medida a 0,6 m fue de 22,5 m s-1. Esto significa que el túnel permite simular velocidades consideradas erosivas a campo. El perfil vertical de viento y la distribución de material erosionado son similares a los producidos en condiciones naturales. El túnel de viento desarrollado cumple con las condiciones de diseño para la simulación de eventos de erosión eólica a campo. El uso del mismo mejorará el estudio de procesos básicos y el desarrollo de tecnología para el control de la erosión eólica en suelos de Argentina, además de ser una fuente de consulta para la construcción de futuros túneles de viento para el estudio de la erosión eólica.Wind erosion (WE) is an irreversible soil degradation process of arid and semiarid regions. With portable wind tunnels it is possible to simulate WE controlling critical variables such as wind speed and direction, duration of erosive events; and soil surface parameters under natural conditions as moisture, roughness and cover level. The objectives of this study were: 1) to describe the main aspects of the design and operation of a portable wind tunnel to study WE, and 2) to calibrate the wind tunnel to fit the aerodynamics criterions related to the development of a vertical wind profile and an eroded material distribution similar to natural conditions. The main components of wind tunnel are chassis, engine, wind fan, s-shaped section, honeycomb diffusor, the stabilization section and the working sections. These sections have 2 m length; 0.5 m width and 1 m height. The wind tunnel was calibrated in an Entic Haplustoll in a bare and flat surface. The maximum measured velocity reached at 0.6 m was 22.5 m s-1, implying that the wind tunnel allows simulating field erosive wind velocities. The vertical wind profile and eroded material distribution are similar to those produced under natural field conditions. The use of this wind tunnel will improve the study of basic processes and technology for wind erosion control of soils of Argentina, also it will serve as a guide for future wind tunnel developments to study wind erosion.Fil: Colazo, Juan Cruz. Instituto Nacional de Tecnología Agropecuaria. Centro Regional La Pampa-San Luis. Estación Experimental Agropecuaria San Luis; ArgentinaFil: Mendez, Mariano Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: de Oro, Laura Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Avecilla, Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Panebianco, Juan Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Buschiazzo, Daniel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentin