Fluides supercritiques et solvants biosourcés : propriétés physicochimiques des systèmes expansés par du CO2

Les objectifs environnementaux (COP21) visant à réduire les émissions de gaz à effet de serre et l'impact de l'industrie sur la nature, font face au défi de la demande croissante d'énergie et de produits. Les procédés chimiques sont les premiers en cause lorsqu’ils mettent en œuvre des solvants. L'ingénierie des solvants est une solution innovante qui vise à trouver des milieux alternatifs bénins possédant les propriétés de solvant adaptés pour chaque étape du procédé.Dans cette perspective, nous avons étudié les Liquides expansés par un gaz (LEGs), qui sont desliquides dont le volume augmente sous l’effet d’un gaz dissous sous pression. En particulier, le CO2 peut être utilisé comme agent d'expansion pour obtenir des liquides expansés par du CO2(LECs), combinant les avantages du CO2 et du solvant. La phase expansée peut contenir des concentrations élevées de CO2, jusqu'à 80%, selon le solvant, ce qui conduit à une réduction du besoin du solvant organique, mais aussi à des changements des propriétés physicochimiques et de transport de la nouvelle phase expansée. On peut de plus moduler ces propriétés par la pression et la température, d'une manière réversible, et améliorer la séparation des produits. Dans cette étude, différents solvants biosourcés ont été utilisés pour obtenir des systèmes expansés par du CO2, tels que les acétates d'alkyle, les carbonates organiques, les méthoxybenzènes, etc.La connaissance des équilibres de phase, des propriétés de solvatation et de transport est essentielle pour concevoir des processus qui exploitent le comportement particulier de ces systèmes biphasiques. Deux approches principales ont été utilisées pour caractériser ces systèmes. Dans un premier temps, des mesures ont été effectuées dans une cellule à haute pression et à volume variable pour évaluer la polarité au travers du paramètre Kamlet-Taft (KT) *(dipolarité / polarisabilité) dans les solvants expansés par du CO2 sous des pressions allant jusqu'à 30 MPa. La technique utilisée a été la spectroscopie UV-Vis suivant le déplacement hypsochromique du Rouge de Nile, une sonde solvatochromique déjà utilisée pour obtenir les paramètres KT dans des solvants purs. De plus, des mesures d'équilibre vapeur-liquide (ELV) ont été effectuées pour obtenir la composition de la phase expansée à différentes pressions et températures afin de comprendre la solvatation du CO2 dans les solvants organiques et de fournir des informations manquantes dans la littérature. En deuxième lieu, dans une approche plus théorique, les données ELV ont été utilisées pour calculer numériquement d'autres propriétés telles que la densité et la viscosité. Des équations d'état et des simulations par dynamique moléculaire (DM) ont été utilisées ; ces dernières donnant de meilleurs résultats dans un mode prédictif de la masse volumique et permettant de suivre les positions moléculaires au cours du temps, qui peut être liée à de nombreuses propriétés, y compris la viscosité étudiée ici. Ces calculs ont été effectués en utilisant un champ de force de type Amber adapté. Les résultats obtenus dans l’ensemble complètent les données de la littérature existante et apportent de nouvelles informations sur les propriétés des LEGs. Par exemple, le comportement non linéaire de l'expansion volumétrique, vérifié après les déterminations de masse volumique sur les simulations DM à l'équilibre, est une clé dans la compréhension des interactions soluté-solvant ; ainsi que les valeurs KT * obtenues qui confirment la large gamme de polarité couverte par ces systèmes.Enfin, certains systèmes expansés par du CO2 ont été utilisés pour produire des nanoparticules de TiO2 pour panneaux solaires, améliorant leur surface spécifique et donc leur efficacité en tant que semi-conducteurs ; et d’autres ont été appliqués à un processus d'activation enzymatique entraînant une augmentation significative du taux de conversio

Development of an amperometric biosensor based on peroxidases from Brassicas napus for the determination of Ochratoxin a content in peanut samples

An amperometric biosensor based on Brassica napus hairy roots peroxidases (BHRP) to determine ochratoxin A (OTA) is proposed by the first time. The enzymatic reaction rate was studied under different experimental conditions and the kinetics parameters were determined. The method employs a dialysis membrane covered, peroxidases entrapped and ferrocene-embedded carbon paste electrode (BHRP-Fc-CP) and is based on the decrease in the amount of H2O2 produced by the action of BHRP is proportional to the concentration of oxidised OTA in solution. BHRP-Fc-CP biosensors showed a very good stability during at least five days. The reproducibility and the repeatability were 7.7% and 5.4%, respectively, showing a good biosensor performance. Comparison between intra and inter assays showed a good accuracy. The calibration curve was linear in the OTA concentration range from 1 x 10-8 to 1.4 x 10-4 mol L-1. The lowest concentration experimentally measured for a signal to noise ratio of 3:1 was 5.7x10-9 mol L-1.Fil: Ramirez, Eduardo Alejandro. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; ArgentinaFil: Granero, Adrian Marcelo. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales; Argentina. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; ArgentinaFil: Zon, María Alicia. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales; ArgentinaFil: Fernandez, Hector. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales; Argentina. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentin

Eating symptomatology and general psychopathology in patients with anorexia nervosa from China, UK and Spain: a cross-cultural study examining the role of social attitudes

Cultural studies exploring differences in the manifestation of anorexia nervosa (AN) have primarily focus on Western and non-Western cultures. However, no study so far has considered the role that social attitudes (i.e. Collectivist vs. Individualist cultural values) have in the clinical manifestations of eating disorders, including AN patients. With this in mind, the aim of this study is to compare eating and general psychopathology in a large sample of individuals diagnosed with AN from China, Spain, and United Kingdom (UK), in order to study the differences according to belonging to Western or non-Western country, or the country's Individualist Index (IDV). The total sample comprised on 544 adults with a diagnosis of AN recruited from People´s Republic of China (n=72), UK (n=117), and Spain (n=355). Assessment measures included the Eating Disorders Inventory and the Symptom Checklist-90- Revised. Our results show significant differences in most of the eating and psychopathological indices between the three countries. Patients from Western societies (Spain and UK) share more similarities regarding psychopathological expression of AN than the non-Western country (China). While Western countries show higher levels of body dissatisfaction, somatization and overall psychopathology, Chinese patients tend to deny or minimize depression, anxiety and other psychopathological symptoms. Besides, the IDV shows cultural differences in the interpersonal sensitivity scale, being AN patients from UK (the more individualistic society) who presented with higher levels of interpersonal sensitivity (i.e. discomfort during interpersonal interactions and more negative expectations concerning interpersonal behavior). In conclusion, our findings suggest that psychopathological expression of AN is better explained by Western/Eastern influence than by individualist/collectivist values. Although the diagnosis for the eating disorder may be the same, differences in the psychopathology comorbid to the eating disorders may suggest the need for treatments to be modified according to the culture

Modulating biocatalytic activity towards sterically bulky substrates in CO2-expanded bio-based liquids by tuning physicochemical properties

The study of CO2-expanded liquids using a green component such as a bio-based solvent has been recently raised as a new concept for an alternative solvent, and yet been largely unexplored in literature for neither fundamental nor application studies. On the other hand, structural bulkiness of substrates remains one of the main limitations to promote enzymes as an efficient versatile catalytic tool for organic synthesis, especially biocatalysis in non-conventional solvents. Herein, we report a detailed investigation of CO2-expanded bio-based liquids as reaction media for improved biocatalysis of sterically hindered compounds. We have found that CO2 acts as a crucial trigger for various lipases to catalyse transesterification of challenging bulky alcohols in CO2-expanded 2-methyltetrahydrofuran (MeTHF). Furthermore, this study determines physicochemical and transport properties of CO2-expanded MeTHF for the first time, which were then utilized for modulating biocatalytic activity. It was found that lipase activity increased with the accordingly decrease of the dipolarity of CO2-expanded MeTHF, which is tunable by altering the concentration of CO2 in the solvent system

Are Neurotrophin Genes Involved in the Pathophysiology of Gambling Disorder?

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Non-suicidal Self-Injury in Eating Disordered Patients: Associations with Heart Rate Variability and State-Trait Anxiety

Background: Non-suicidal self-injury (NSSI) is commonly present in individuals with eating disorders (EDs) and is often employed as a maladaptive emotion regulation strategy to avoid or abate negative emotions. One of the most prevalent negative emotions experienced by self-injurers is anxiety; however, this emotion has not been extensively studied in this population. Thus, the aim of our study was to investigate the influence of anxiety on NSSI in patients with ED from two different dimensions: state anxiety and trait anxiety.Methods: The study comprised a total of 66 females: 12 ED patients with NSSI, 32 ED patients without a history of NSSI, and 22 healthy controls. State and trait anxiety were assessed by means of State-Trait Anxiety Inventory (STAI-S-T) and physiological data [i.e., heart rate variability (HRV)] were collected.Results: STAI-trait scores were significantly higher in ED patients with NSSI than ED patients without NSSI. Furthermore, when conducting logistic regression analyses higher STAI-trait scores were associated with NSSI in ED patients. However, no differences in STAI-state scores and HRV were found between ED patients with and without NSSI.Discussion: The present findings suggest that anxiety as a trait is associated with the use of maladaptive strategies (i.e., NSSI) in ED patients. These results uphold the need to target trait anxiety in ED treatment in order to prevent possible NSSI behaviors

Development of Electrochemical Sensors/Biosensors to Detect Natural and Synthetic Compounds Related to Agroalimentary, Environmental and Health Systems in Argentina: A Review of the Last Decade

Electrochemical sensors and biosensors are analytical tools, which are in continuous development with the aim of generating new analytical devices which are more reliable, cheaper, faster, sensitive, selective, and robust than others. In matrices related to agroalimentary, environmental, or health systems, natural or synthetic compounds occur which fulfil specific roles; some of them (such as mycotoxins or herbicides) may possess harmful properties, and others (such as antioxidants) beneficial ones. This imposes a challenge to develop new tools and analytical methodologies for their detection and quantification. This review summarises different aspects related to the development of electrochemical sensors and biosensors carried out in Argentina in the last ten years for application in agroalimentary, environmental, and health fields. The discussion focuses on the construction and development of electroanalytical methodologies for the determination of mycotoxins, herbicides, and natural and synthetic antioxidants. Studies based on the use of different electrode materials modified with micro/nanostructures, functional groups, and biomolecules, complemented by the use of chemometric tools, are explored. Results of the latest reports from research groups in Argentina are presented. The main goals are highlighted.Fil: Granero, Adrian Marcelo. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; ArgentinaFil: Fernandez, Hector. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; ArgentinaFil: Zon, María Alicia. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; ArgentinaFil: Robledo, Sebastian Noel. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; ArgentinaFil: Pierini, Gastón Dario. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; ArgentinaFil: Di Tocco, Aylen. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; ArgentinaFil: Carrillo Palomino, Roodney Alberto. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; ArgentinaFil: Maccio, Sabrina Antonella. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; ArgentinaFil: Riberi, Walter Iván. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; ArgentinaFil: Arevalo, Fernando Javier. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentin

Eating symptomatology and general psychopathology in patients with anorexia nervosa from China, UK and Spain: a cross-cultural study examining the role of social attitudes

Cultural studies exploring differences in the manifestation of anorexia nervosa (AN) have primarily focus on Western and non-Western cultures. However, no study so far has considered the role that social attitudes (i.e. Collectivist vs. Individualist cultural values) have in the clinical manifestations of eating disorders, including AN patients. With this in mind, the aim of this study is to compare eating and general psychopathology in a large sample of individuals diagnosed with AN from China, Spain, and United Kingdom (UK), in order to study the differences according to belonging to Western or non-Western country, or the country's Individualist Index (IDV). The total sample comprised on 544 adults with a diagnosis of AN recruited from People´s Republic of China (n=72), UK (n=117), and Spain (n=355). Assessment measures included the Eating Disorders Inventory and the Symptom Checklist-90- Revised. Our results show significant differences in most of the eating and psychopathological indices between the three countries. Patients from Western societies (Spain and UK) share more similarities regarding psychopathological expression of AN than the non-Western country (China). While Western countries show higher levels of body dissatisfaction, somatization and overall psychopathology, Chinese patients tend to deny or minimize depression, anxiety and other psychopathological symptoms. Besides, the IDV shows cultural differences in the interpersonal sensitivity scale, being AN patients from UK (the more individualistic society) who presented with higher levels of interpersonal sensitivity (i.e. discomfort during interpersonal interactions and more negative expectations concerning interpersonal behavior). In conclusion, our findings suggest that psychopathological expression of AN is better explained by Western/Eastern influence than by individualist/collectivist values. Although the diagnosis for the eating disorder may be the same, differences in the psychopathology comorbid to the eating disorders may suggest the need for treatments to be modified according to the culture