Abstract The analysis of glacial and ice-marginal systems may contribute to understanding the impact of climatic change. The aim of this study is to investigate changes in the glacial, proglacial and paraglacial system in response to the Collins glacier retreat, between the Little Ice Age (LIA) and 2070. Glacial geomorphological mapping reveals landforms that are diagnostic of a terrestrial-terminating glacier in the past. Glacial and the proglacial systems were mapped to evaluate the ice-marginal evolution. The field measurement, satellite imagery, granulometric and morphoscopic sedimentary analysis, and geomorphological data are analyzed. The Collins glacier surface topography has been surveyed by DGNSS during 11 years (1997/98-2008/09) and for glacier area estimation in 2030, 2050 and 2070 CE. The Collins glacier lost 1.4 km² in the period LIA-2018. Under an atmospheric warming scenario, using the temperature melt index model the glacier will lose approximately 5% of its total area until 2030 (0.90 km²), 21% (3.60 km²) by 2050, and 35% (5.90 km²) by 2070 CE. Four sectors in the proglacial zone are identified: Sector 1 displays changes on the front of the glacier since the LIA, a push moraine in only one sector, presence of flutings and moraines of recession. Sector 2 showed shrinkage around 100 meters in the period LIA-2018, presenting recessional and push moraines of about 10 meters of height. Sector 3 showed 350 meters of the shrinkage since the LIA, and recessional moraines, and absence of the push moraines. Sector 4, showed 1500 meters of the shrinkage since the LIA, a push moraine of about 12 meters high. This behavior that occurs since the LIA allows validating the future scenario model. The ice-free areas could expand 1,4 km² by the end of 2070 decade if considered since LIA. However, it should be noted that if the glacier continues to retreat, the system will be subject to hydrological and sedimentary readjustments at various stages in the future.

Resumen El análisis de los sistemas glaciales y marginales al hielo puede contribuir para la comprensión del impacto de los cambios climáticos. De esta forma, el objetivo de este estudio es investigar los cambios en el sistema glacial, proglacial y periglacial en respuesta al retroceso del glaciar Collins, entre la Pequeña Edad del Hielo (PEH) y 2070. La Península Fildes, parte sur de la isla Rey Jorge (latitud entre 62° 08' y 62° 14' S y longitud entre 59°02' e 58°51' O), es una de las primeras áreas a quedarse libre del hielo en el archipiélago de las Shetland del Sur después del Último Máximo Glacial. La elección por esta área de estudio en la isla Rey Jorge se justifica por la facilidad de se accender a ella para la realización de trabajos de campo y también porque hay investigaciones previas sobre ella que indican la retracción de los glaciales. Para evaluar la evolución marginal del hielo se mapearon los sistemas glacial y proglacial. Se interpretaron y se delimitaron las etapas de retracción desde la PEH por la posición de las morrenas de recesión y por la cronología establecida por imágenes de satélite. Se utilizaron imágenes Landsat de los sensores TM, ETM+ y OLI referentes a las fechas 03/01/1986, 27/02/1988, 28/01/1989, 19/01/2003, 17/03/2015 y 29/04/2018 para establecer los valores de retracción del glaciar Collins. Para elaborar el mapeo geomorfológico actual se analizaron datos de trabajos de campo realizados en 2013, 2014 y 2015; imágenes de satélite Quickbird de febrero de 2008; análisis granulométricos y morfoscópicos de sedimientos recolectados en los principales accidentes geográficos del area proglacial del glaciar Collins y datos del Modelo de Elevación Digital TanDEM-X. La topografia de la superfície del glaciar Collins fue obtenida por DGNSS a lo largo de 11 años (1997/98-2008/09) y se utilizaron los datos para calculcular el área y el espesor aproximados del glaciar en 2030, 2050 y 2070. Acerca de los resultados, se destaca que el glaciar Collins perdió 1,4km2 en el período PEH. En un escenario de calentamiento atmosférico, utilizando el modelo de índice de derretimiento, el glaciar perderá aproximadamente el 5% de su área total hasta 2030 (0,90 km²), el 21% (3,60 km²) hasta 2050 y el 35% (5, 90 km²) hasta 2070. Se identificaron cuatro sectores en la zona proglacial: el sector 1 presentó cambios enfrente del glaciar desde la PEH, presencia de flutings y morrenas de recesión. El sector 2 presentró una retracción alrededor de 100 metros en el período PEH-2018, con el depósito de morrenas de recesión de cerca de 2 m de altura y de morrenas de empuje de unos 10 metros de altura. El sector 3 presentó 350 metros de retracción desde el PEH, formación de morrenas de recesión y ausencia de morrenas de empuje. El sector 4 presentó 1.500 metros de retracción desde el PEH, formando una morrena de empuje de cerca de 12 metros de altura. Este comportamiento, que ocurre desde la PEH, permite validar el modelo de escenario futuro. Las áreas libres de hielo pueden expandirse 1,4 km² en el período PEH-2070. Considerando el proceso hidrológico y sedimentológico, las áreas más dinámicas serán los sectores 1 y 2, debido al retroceso más rápido del glaciar. Cabe destacar que la zona recientemente libre de hielo del glaciar Collins también estará sujeta a procesos periglaciales que podrán ser analizados solamente mediante una evaluación sistémica, considerando interacciones y cambios en los sistemas hidrológico, sedimentario y biológico. Sin embargo, se estima que los procesos periglaciales probablemente predominarán a lo largo de la primera etapa posterior al retroceso del glaciar Collins, presentando un área inestable, con una alta concentración de sedimentos que forman accidentes geográficos como morrenas, eskers, flutings y canales entrelazados capaces de transportar material para la actual zona proglacial. El área proglacial actual probablemente cambiará debido a la reducción del suministro de agua de deshielo y a una mayor distancia de los glaciales. Cabe señalar que el modelo del índice de derretimiento no considera las variaciones en la temperatura del aire, lo que obviamente puede generar diferencias en los escenarios propuestos. Sin embargo, se destaca que los resultados encontrados en esta investigación son consistentes con los valores de retracción de volumen y de área de los glaciares de la isla Rey Jorge y de la Península Antártica encontrados en otros artículos. Se destaca, también, que los resultados encontrados en esta investigación están de acuerdo con los valores de retracción de volumen y de área de los glaciares de la Isla Rey Jorge y de la Península Antártica encontrados en otros artículos.

Objective: The marked increase in the prevalence of attention-deficit/hyperactivity disorder (ADHD) among university students gives rise to questions about how best to diagnose in this setting. The aim of the present study was to calculate ADHD prevalence in a large non-clinical sample of medical students using a stepwise design and to determine whether ADHD diagnosis varies if interviewees use additional probing procedures to obtain examples of positive DSM items. Methods: A total of 726 students were screened with the Adult Self-Report Scale (ASRS) and invited for an interview with the Kiddie Schedule for Affective Disorders and Schizophrenia (K-SADS) adapted for adults. Results: The ASRS was positive for 247 students (37%), although only 83 (7.9%) received an ADHD diagnosis. ASRS sensitivity and specificity rates were 0.97 and 0.40, respectively. Probing procedures were used with a subgroup of 226 students, which decreased the number of ADHD diagnoses to 12 (4.5%). Conclusion: Probing for an individual’s real-life examples during the K-SADS interview almost halved ADHD prevalence rate based on the ASRS and K-SADS, which rendered the rate consistent with that typically reported for young adults. In reclassified cases, although examples of inattention did not match the corresponding DSM item, they often referred to another DSM inattention item.

RESUMO O Transtorno do Déficit de Atenção/Hiperatividade (TDAH) compreende diversos outros sintomas além de desatenção, hiperatividade e impulsividade, tais como problemas de linguagem. O TDAH pode cursar sem remissão, tendo sido demonstrado em indivíduos mais velhos, porém não há estudos investigando a linguagem em idosos com o transtorno. Objetivo: Investigar a presença de déficits de linguagem em adultos mais velhos portadores de TDAH. Métodos: Avaliou-se a presença de comprometimento de linguagem em três adultos mais velhos com TDAH, que foram comparados a dois indivíduos controles pareados, através de tarefa de discurso narrativo. A transcrição das narrativas foi avaliada com base no modelo de análise de narrativa de Trabasso, e então analisada com uso do programa Speech Graph Analysis. Resultados: Comparados aos indivíduos controles, adultos mais velhos com TDAH utilizaram mais componentes (Núcleos) da história em suas narrativas e suas redes mais Arestas. Eles apresentaram escores mais altos no Índice de Ineficiência, Diâmetro e Densidade e também no Coeficiente Médio de Grupamento. As redes dos indivíduos controles foram lineares e sequenciais, com pouca ou nenhuma recursividade, ao contrário das redes de adultos com TDAH. Conclusão: Estes resultados sugerem que problemas de linguagem já descritos em crianças, adolescentes e adultos com TDAH, podem persistir em adultos mais velhos com o transtorno.

ABSTRACT Attention-Deficit Hyperactivity Disorder (ADHD) encompasses other symptoms besides inattention, hyperactivity, and impulsivity, such as language problems. ADHD can have a non-remitting course and is also found in older individuals, although there are no studies on language problems in elderly individuals with the disorder. Objective: To investigate the presence of language impairment in older adults with ADHD. Methods: Language impairment was investigated in three older ADHD adults, and compared with two matched control subjects using a narrative discourse task. The transcript discourses were evaluated based on the Trabasso Model for discourse analysis, and then processed by the Speech Graph Analysis software. Results: Compared to control subjects, ADHD patient discourse had more Plot components and their networks exhibited more Edges. The patients had higher scores on the Narrative Inefficiency, Density and Diameter Indexes as well as on the Average Clustering Coefficient. The networks of control subjects were sequential, with little or no recursiveness, whereas those of ADHD subjects were convoluted. Conclusion: Our results suggest that language deficits described in children, adolescents and young adults with ADHD may persist in older adults with the disorder.

This study was developed in order to evaluate two alternatives for the control of Listeria monocytogenes in raw bovine meat pieces, both based on the use of Thymus vulgaris and Rosmarinus officinalis essential oils (EOs). The antilisterial activity of different concentrations of the EOs was tested in vitro using agar dilution and disk volatilization techniques. In addition, L. monocytogenes was inoculated in meat pieces, which were submerged in edible gelatin coatings containing 2% (v/v) EOs or submitted to the vapor of EOs (0.74 μL.cm-3). L. monocytogenes was quantified after one, 48 and 96 hours of storage (7 °C). In the in vitro tests, the EO of T. vulgaris presented higher activity. The two options used (edible gelatin coating and vapor activity), in spite of exercising effects with differentiated behaviors, presented antibacterial activity against L. monocytogenes inoculated in raw bovine meat (p < 0.05). Greatest antibacterial activity were obtained in the experiment that used edible coatings containing EOs, at 48 hours of storage reductions in bacterial counts between 1.09 and 1.25 Log CFU.g-1 were obtained. In the vapor effect experiment, the EO of T. vulgaris caused the highest reduction in the population of bacteria inoculated in raw bovine meat (p < 0.05), 0.40 Log CFU.g-1 at 96 hours of storage. This study supplied important information regarding new and promising natural alternatives, based on the concept of active packaging, for the control of L. monocytogenes in the meat industry.

Extratos etanólicos de 23 ervas e condimentos desidratados comercializados no Brasil foram analisados quanto as suas propriedades antioxidantes utilizando os radicais 2,2'-difenil-β-picrilhidrazil (DPPH•) e ácido 2,2'-azino-bis(3-etilbenzotiazolina-6-sulfônico) (ABTS•+), Trolox foi usado como referência para ambos radicais. As curvas cinéticas seguiram o modelo cinético de primeira ordem, e a partir destas foram calculadas as constantes de velocidade de (k obs). Os extratos de sálvia e de alecrim apresentaram as maiores capacidades redutoras de radicais livres, enquanto o extrato de cebola praticamente não apresentou atividade e o colorífico, um dos condimentos mais consumidos no Brasil, apresentou baixa atividade de aprisionamento de radicaisABTS•+. Três situações distintas foram observadas em relação à capacidade de aprisionar radicais DPPH•: (1) extratos, como os de alecrim e de louro, que apresentaram as mesmas concentrações eficientes (EC50), porém, valores de TEAC e velocidade de ação (k obs) distintos ; (2) extratos, como os de alho e de manjericão, que apresentaram valores similares de EC50 e TEAC, com valores distintos de k obs e (3) extratos com a mesma velocidade de ação que diferiram totalmente na capacidade de aprisionamento de radicais livres, como de pimenta preta, segurelha, noz moscada, alecrim e sálvia. Considerações semelhantes podem ser feitas para os resultados de ABTS•+. Osdois métodos apresentaram boa correlação de TEAC, indicando que a reatividade dos compostos presentes nos extratos etanólicos foi similar. A atividade redutora de ABTS•+ para pimenta da Jamaica, manjericão, cardamomo, cebolinha, colorífico, cominho, dill, louro, manjerona, salsinha e estragão foi reportada pela primeira vez.

Ethanolic extracts from 23 different dried herbs and spices commercialized in Brazil were investigated for their free radical scavenging properties using the stable free radicals 2,2'-diphenyl-β-picrylhydrazyl (DPPH•) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS•+), and Trolox as reference (TEAC) for both radicals. The kinetic curves for both radicals showed to follow the first order kinetics model and the decay rate constant (k obs) was calculated. For all the samples, the two methods showed a good linear TEAC correlation, indicating that the average reactivity of the compounds present in the ethanolic extracts was similar. Sage and rosemary extracts showed the highest free radical scavenging capacities, while onion showed negligible activity and colorifico, one of the most consumed spices in Brazil, showed low ABTS•+ scavenging activity. Three distinct situations were found for the extracts concerning the DPPH• scavenging capacities: (1) extracts, like rosemary and laurel, that presented the same efficient concentrations (EC50 ) but differed in the TEAC values and velocities of action (k obs), (2) extracts, such as garlic and basil, that showed similar EC50 and TEAC values, but different k obs values and (3) extracts that reacted at the same velocities but completely differed in the free radical scavenging capacities, like black pepper, savory, nutmeg, rosemary and sage. Similar considerations could be done for the ABTS•+ results. For the first time the ABTS•+ scavenging activity for allspice, basil, cardamom, chives, colorifico, cumin, dill, laurel, marjoram, parsley and tarragon was reported.

The aim of this work was to evaluate the antioxidant properties of ginger and rosemary extracts, obtained by supercritical extraction. The extracts were characterized by HPLC, GC-MS, phenolic compounds content and antioxidant activity. The main active compounds were identified and high content of phenolic compounds was observed. The extracts presented high antioxidant activity against the free radicals ABTS•+ (350 and 200 mM Trolox/g, for ginger and rosemary, respectively) and DPPH•+ (145 and 80 mM Trolox/g, for ginger and rosemary, respectively). These results suggested that the attained extracts are potential substitutes of synthetic antioxidants used in chemical, food and pharmaceutical industries.