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56 Dunning-Kruger Effect and Anxiety in a Mexican population
- Natalia L. Acosta, Krissy E. Smith, Tara L. Victor, David H. Hardy, Alberto L. Fernandez, Raymundo Cervantes, Ana Paula P. Quiñones, Carolina G. Castañeda, Jill Razani, Isabel D.C. Muñoz, Daniel W. Lopez-Hernandez
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- Journal:
- Journal of the International Neuropsychological Society / Volume 29 / Issue s1 / November 2023
- Published online by Cambridge University Press:
- 21 December 2023, pp. 841-842
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Objective:
The Dunning-Krueger effect is a cognitive bias where individuals tend to overestimate their abilities in areas where they are less competent. The Cordoba Naming Test (CNT) is a 30-item confrontation naming task. Hardy and Wright (2018) conditionally validated a measure of perceived mental workload called the NASA Task Load Index (NASA-TLX). Researchers reported that workload ratings on the NASA-TLX increased with increased task demands on a cognitive task. Anxiety is known as an emotion that can make an individual more susceptible to develop a mental health condition. We examine if the Dunning-Krueger effect occurs in a Mexican population with and without current symptoms of anxiety and possible factors driving individuals to overestimate their abilities on the CNT. We predicted the abnormal symptoms of anxiety (ASA) group would report better CNT performance, report higher perceived workloads on the CNT, and underperform on the CNT compared to the normal symptoms of anxiety (NSA) group. We also predicted the low-performance group would report better CNT performance, report higher perceived workloads on the CNT, and underperform on the CNT compared to the high-performance group.
Participants and Methods:The sample consisted of 192 Mexican participants with NSA (79 low-performance & 113 high-performance) and 74 Mexican participants with ASA (44 low-performance & 30 high-performance). Participants completed the CNT, NASA-TLX, and the Hospital Anxiety and Depression Scale (HADS) in Spanish. The NASA-TLX was used to evaluate perceived workloads after the completion of the CNT. Meanwhile, the HADS was used to create our anxiety groups. Finally, CNT raw scores were converted into T-scores, which then were averaged to create the following two groups: low-performance (CNT T-Score <50) and high-performance (CNT T-Score 50+). A series of 2x2 ANCOVAs, controlling for gender were used to evaluate CNT performance and perceived workloads.
Results:We found a significant interaction where the low-performance ASA and the high-performance NSA groups demonstrated better CNT performance and reported higher perceived workloads (i.e., performance, temporal demand) on the CNT compared to their respective counterparts (i.e., low-performance NSA & high-performance ASA groups), p's<.05, ηp's2=.02. We found a main effect where the high-performance group outperformed the low-performance group on the CNT and reported lower perceived workloads on the CNT, p's<.05, ηp's2 =.04-.46.
Conclusions:The Dunning-Krueger effect did not occur in our sample. Participants that demonstrated better CNT performance also reported higher perceived workloads regardless of their current symptoms of anxiety. A possible explanation can be our sample's cultural norms of what would be considered as abnormal symptoms of anxiety, is a normal part of life, decreasing the possibilities to experience self-efficacy distoritions. Future studies should investigate whether the Dunning-Kruger effect may be influencing other aspects of cognitive functioning subjectively in Mexicans residing in Mexico and the United States with and without current symptoms of anxiety.
8 The Dunning-Kruger Effect on a Latinx Population
- Carolina Garza Castaneda, Matthew J. Wright, Raymundo Cervantes, Tara L. Victor, Krissy E. Smith, Chelsea McElwee, Adriana Cuello, Alberto L. Fernandez, Isabel D. C. Munoz, David J. Hardy, Daniel W. Lopez-Hernandez
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- Journal:
- Journal of the International Neuropsychological Society / Volume 29 / Issue s1 / November 2023
- Published online by Cambridge University Press:
- 21 December 2023, pp. 423-424
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Objective:
Individuals tend to overestimate their abilities in areas where they are less competent. This cognitive bias is known as the Dunning-Krueger effect. Research shows that Dunning-Krueger effect occurs in persons with traumatic brain injury and healthy comparison participants. It was suggested by Walker and colleagues (2017) that the deficits in cognitive awareness may be due to brain injury. Confrontational naming tasks (e.g., Boston Naming Test) are used to evaluate language abilities. The Cordoba Naming Test (CNT) is a 30-item confrontational naming task developed to be administered in multiple languages. Hardy and Wright (2018) conditionally validated a measure of perceived mental workload called the NASA Task Load Index (NASA-TLX). They found that workload ratings on the NASA-TLX increased with increased task demands on a cognitive task. The purpose of the present study was to determine whether the Dunning-Kruger effect occurs in a Latinx population and possible factors driving individuals to overestimate their abilities on the CNT. We predicted the low-performance group would report better CNT performance, but underperform on the CNT compared to the high-performance group.
Participants and Methods:The sample consisted of 129 Latinx participants with a mean age of 21.07 (SD = 4.57). Participants were neurologically and psychologically healthy. Our sample was divided into two groups: the low-performance group and the high-performance group. Participants completed the CNT and the NASA-TLX in English. The NASA-TLX examines perceived workload (e.g., performance) and it was used in the present study to evaluate possible factors driving individuals to overestimate their abilities on the CNT. Participants completed the NASA-TLX after completing the CNT. Moreover, the CNT raw scores were averaged to create the following two groups: low-performance (CNT raw score <17) and high-performance (CNT raw score 18+). A series of ANCOVA's, controlling for gender and years of education completed were used to evaluate CNT performance and CNT perceived workloads.
Results:We found the low-performance group reported better performance on the CNT compared to the high-performance, p = .021, np2 = .04. However, the high-performance group outperformed the low-performance group on the CNT, p = .000, np2 = .53. Additionally, results revealed the low-performance group reported higher temporal demand and effort levels on the CNT compared to the high-performance group, p's < .05, nps2 = .05.
Conclusions:As we predicted, the low-performance group overestimated their CNT performance compared to the high-performance group. The current data suggest that the Dunning-Kruger effect occurs in healthy Latinx participants. We also found that temporal demand and effort may be influencing awareness in the low-performance group CNT performance compared to the high-performance group. The present study suggests subjective features on what may be influencing confrontational naming task performance in low-performance individuals more than highperformance individuals on the CNT. Current literature shows that bilingual speakers underperformed on confrontational naming tasks compared to monolingual speakers. Future studies should investigate if the Dunning-Kruger effects Latinx English monolingual speakers compared to Spanish-English bilingual speakers on the CNT.
42 Lexical Retrieval and Acculturation in Generation Z Mexicans
- Yvette D Jesus, Krissy E Smith, Krithika Sivaramakrishnan, Reymundo Cervantes, Tara L Victor, Brittany Heuchert, Dorthy Schmidt, Diana Palacios, Chelsea McElwee, David J Hardy, Enrique Lopez, Alberto L Fernandez, Daniel W Lopez Hernandez
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- Journal:
- Journal of the International Neuropsychological Society / Volume 29 / Issue s1 / November 2023
- Published online by Cambridge University Press:
- 21 December 2023, p. 453
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The Cordoba Naming Test (CNT) is a 30-item lexical retrieval task that was developed to be administered in multiple languages. Research shows that self-identifying Mexicans residing in Mexico outperform self-identifying Mexicans that reside in the United States on the CNT. Studies indicate that the process of acculturation can influence cognitive performance. Previous studies demonstrated that Generation Z individuals (i.e., people born between 1997 and 2012) have underperformed on the CNT compared to Generation Y individuals (i.e., people born between 1981 and 1996). To our knowledge, no study has examined the influence of acculturation on Generation Z Mexicans’ CNT performance. We expected Mexicans residing in Mexico (MRM) to outperform Mexicans residing in the United States on the CNT and to report higher acculturation traits. We also predicted that acculturation would correlate with CNT performance.
Participants and Methods:The present study sample consisted of 285 Generation Z psychologically and neurologically healthy Mexicans with a mean age of 20.32 (SD = 1.60). Participants were divided into three groups: MRM, Mexicans residing in the United States, and Mexican-Americans residing in the United States (MARUS). All participants completed the CNT and acculturation measure in Spanish. Acculturation traits were measured by the Abbreviated Multidimensional Acculturation Scale (AMAS). ANCOVAs were used to evaluate differences in the CNT and AMAS (i.e., Spanish language, Latino competency, Latino identity). Pearson’s correlation coefficient was used to evaluate the relationship between acculturation on CNT performance.
Results:MRM outperformed the Mexicans residing in the United States and MARUS on the CNT, p = .000, np2 = .49. The MRM group reported better Spanish language abilities compared to Mexicans residing in the United States and the MARUS groups, p = .000, np2 = .10. Additionally, MRM reported better Latino competency than the MARUS group, p = .000, np2 = .08. Pearson’s correlation coefficient revealed that the MARUS’s Spanish language abilities impacted CNT performance, p = .000, r = .48. In addition, we found that Latino competency correlated with CNT performance, p’s < .05, r’s = .20-.47, in both the MRM and Mexicans residing in the United States groups. Latino identity did not significantly correlate with CNT performance in any group.
Conclusions:Results confirmed that MRM individuals perform better on the CNT than Mexicans residing in the United States and MARUS. Additionally, we found that several acculturation traits correlated with Mexican groups’ CNT performance. Our research indicates that while all Generation Z individuals of Mexican heritage feel strongly connected to their Latino identity regardless of where they live, MARUS feel less competent in Spanish and Latinx culture than MRM and Mexicans residing in the United States. Future work should further explore these differences for better insight into how acculturative factors influence lexical retrieval performance. Future work with bigger sample sizes can additionally examine CNT performance and acculturation in Generation Z first-generation and non-first-generation Mexicans (e.g., second-generation, third-generation) residing in the United States.
22 Cordoba Naming Test Performance and Acculturation in a Geriatric Population
- Isabel C.D. Muñoz, Krissy E. Smith, Santiago I. Espinoza, Diana M. R. Maqueda, Adriana C. Cuello, Ana Paula Pena, Carolina Garza, Raymundo Cervantes, Jill Razani, Tara L. Victor, David J. Hardy, Alberto L. Fernandez, Natalia Lozano Acosta, Daniel W. Lopez-Hernandez
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- Journal:
- Journal of the International Neuropsychological Society / Volume 29 / Issue s1 / November 2023
- Published online by Cambridge University Press:
- 21 December 2023, pp. 335-336
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Objective:
A commonly used confrontation naming task used in the United States is The Boston Naming Test (BNT). Performance differences has been found in Caucasian and ethnic minorities on the BNT. The Cordoba Naming Test (CNT) is a 30-item confrontation naming task developed in Argentina. Past research has shown acculturation levels can influence cognitive performance. Furthermore, one study evaluated geriatric gender differences on CNT performance in Spanish. Researchers reported that older male participants outperformed female participants on the CNT. To our knowledge, researchers have not evaluated ethnic differences on the CNT using a geriatric sample. The purpose of the present study was to examined CNT performance and acculturation in a Latinx and Caucasian geriatric sample. It was predicted the Caucasian group would outperform the Latinx group on the CNT. Moreover, the Caucasian group would report higher acculturation levels on the Abbreviated Multidimensional Acculturation Scale (AMAS) compared to the Latinx group.
Participants and Methods:The sample consisted of 9 Latinx and 11 Caucasian participants with a mean age of 66.80 (SD =6.10), with an average of 14.30 (SD = 2.00) years of education. All participants were neurologically and psychologically healthy and completed the CNT and the AMAS in English. Acculturation was measured via the AMAS English subscales (i.e., English Language, United States. Identity, United States, Competency). A series of ANCOVAs, controlling for years of education completed and gender, was used to evaluate CNT performance and acculturation.
Results:The ethnic groups were not well demographically matched (i.e., years of education and gender).We found that the Caucasian group outperformed the Latinx group on CNT performance p = .012, ηp 2 = .34. Furthermore, the Caucasian group reported higher acculturation levels (i.e., English Language, United States, Identity, United States, Competency) compared to the Latinx group p’s < .05, ηps2 = .42-.64.
Conclusions:To our knowledge, this is the first study to evaluate CNT performance between ethnic groups with a geriatric sample. As expected the Caucasian group outperformed the Latinx group on the CNT. Also, as expected the Caucasian group reported higher English acculturation levels compared to the Latinx group. Our findings are consistent with past studies showing ethnic differences on confrontational naming performance (i.e., The Boston Naming Test), favoring Caucasians. A possible explanation for group differences could have been linguistic factors (e.g., speaking multiple languages) in our Latinx group. Therefore, since our Latinx group reported lower levels of English Language, United States identity, and United States competency the Latinx group assimilation towards United States culture might of influence their CNT performance. Future studies with different ethnic groups (e.g., African-Americans) and a larger sample size should examine if ethnic differences continue to cross-validate in a geriatric sample.
30 Analyzing Spanish Speakers Cordoba Naming Test Performance
- Raymundo Cervantes, Isabel D.C. Munoz, Estefania J. Aguirre, Natalia Lozano Acosta, Mariam Gomez, Adriana C. Cuello, Krissy E. Smith, Diana I. Palacios Mata, Krithika Sivaramakrishnan, Yvette De Jesus, Santiago I. Espinoza, Diana M. R. Maqueda, David J. Hardy, Tara L. Victor, Alberto L. Fernandez, Daniel W. Lopez-Hernandez
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- Journal:
- Journal of the International Neuropsychological Society / Volume 29 / Issue s1 / November 2023
- Published online by Cambridge University Press:
- 21 December 2023, pp. 443-444
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A 30-item confrontation naming test was developed in Argentina for Spanish speakers, The Cordoba Naming Test (CNT). The Boston Naming Test is an established confrontation naming task in the United States. Researchers have used the Boston Naming Test to identify individuals with different clinical pathologies (e.g., Alzheimer’s disease). The current literature on how Spanish speakers across various countries perform on confrontational naming tasks is limited. To our knowledge, one study investigated CNT performance across three Spanish-speaking countries (i.e., Argentina, Mexico, and Guatemala). Investigators found that the Guatemalan group underperformed on the CNT compared to the Argentine and Mexican groups. The purpose of this study was to extend the current literature and investigate CNT performance across five Spanish-speaking countries (i.e., Argentina, Mexico, Guatemala, Colombia, United States). We predicted that the Argentine group would outperform the other Spanish-speaking countries.
Participants and Methods:The present study sample consisted of 502 neurologically and psychologically healthy participants with a mean age of 29.06 (SD = 13.41) with 14.75 years of education completed (SD = 3.01). Participants were divided into five different groups based on their country of birth and current country residency (i.e., United States, Mexico, Guatemala, Argentina, & Colombia). All participants consented to voluntary participation and completed the CNT and a comprehensive background questionnaire in Spanish. The CNT consisted of 30 black and white line drawings, ranging from easy to hard in difficulty. An ANCOVA, controlling for gender, education, and age, was used to evaluate CNT performance between the five Spanish-speaking country groups. Meanwhile, a Bonferroni post-hoc test was utilized to evaluate the significant differences between Spanish-speaking groups. We used a threshold of p < .05 for statistical significance.
Results:Results revealed significant group differences between the five Spanish speaking groups on the CNT, p = .000, np2 = .48. Bonferroni post-hoc test revealed that the United States group significantly underperformed on the CNT compared to all the Spanish-speaking groups. Next, we found the Guatemalan group underperformed on the CNT compared to the Argentinian, Mexican, and Colombian groups. Additionally, we found the Argentinian group outperformed the Mexican, Guatemalan, and United States groups on the CNT. No significant differences were found between the Argentinian group and Colombian group or the Mexican group and Colombian group on the CNT.
Conclusions:As predicted, the Argentinian group outperformed all the Spanish-speaking groups on the CNT except the Colombian group. Additionally, we found that the United States group underperformed on the CNT compared to all the Spanish-speaking groups. A possible explanation is that Spanish is not the official language in the United States compared to the rest of the Spanish-speaking groups. Meanwhile, a possible reason why the Argentinian and Colombian groups demonstrated better CNT performances might have been that it was less culturally sensitive than the United States, Mexican, and Guatemalan groups. Further analysis is needed with bigger sample sizes across other Spanish-speaking countries (e.g., Costa Rica, Chile) to evaluate what variables, if any, are influencing CNT performance.
Transnational research for coastal wetlands conservation in a Cuba–US setting
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- Victoria C. Ramenzoni, Mark R. Besonen, David Yoskowitz, Vanessa Vázquez Sánchez, Armando Rangel Rivero, Patricia González-Díaz, Armando Falcón Méndez, Daily Borroto Escuela, Idania Hernández Ramos, Norgis Valentín Hernández López, Larry McKinney
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- Global Sustainability / Volume 3 / 2020
- Published online by Cambridge University Press:
- 15 July 2020, e19
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Sharing information between different countries is key for developing sustainable solutions to environmental change. Coastal wetlands in the Gulf of Mexico are suffering significant environmental and human-related threats. Working across national boundaries, this research project brings together scientists, specialists and local communities from Cuba and the USA. While important advances have been made in strengthening collaborations, important obstacles remain in terms of international policy constraints, different institutional and academic cultures and technology. Overcoming these limitations is essential to formulating a comprehensive understanding of the challenges that coastal socioecological systems are facing now and into the future.
Epiphytic diatoms of Thalassia testudinum (Hydrocharitaceae) from the Mexican Caribbean
- Francisco Omar López-Fuerte, David A. Siqueiros-Beltrones, Oscar U. Hernández-Almeida
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- Marine Biodiversity Records / Volume 6 / 2013
- Published online by Cambridge University Press:
- 19 September 2013, e107
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- 2013
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The first list of epiphytic diatom species on the seagrass Thalassia testudinum from the Yalahau lagoon area in the Mexican Caribbean is given. One hundred and seven diatom taxa living on T. testudinum were identified including species and varieties. Nine taxa are new records for Mexico. The Bacillariophyceae with 87 taxa were the most diverse group. The most abundant taxa were: Cocconeis lineata, Mastogloia crucicula var. crucicula, Cocconeis thalassiana, Cocconeis scutellum var. scutellum and Mastogloia ovata, representing approximately 75% of the total valve count (N = 1527). Yalahau lagoon samples from site 1 yielded a high number of rare taxa. Species richness (S), diversity (H′, 1-λ) and equitability (J′) for the lagoon were lower than for Cabo Catoche (site 2). Based on presence/absence of species, the measured similarity (60%) suggests that the diatom assemblages growing on T. testudinum in the two localities are different.
The science of EChO
- Giovanna Tinetti, James Y-K. Cho, Caitlin A. Griffith, Olivier Grasset, Lee Grenfell, Tristan Guillot, Tommi T. Koskinen, Julianne I. Moses, David Pinfield, Jonathan Tennyson, Marcell Tessenyi, Robin Wordsworth, Alan Aylward, Roy van Boekel, Angioletta Coradini, Therese Encrenaz, Ignas Snellen, Maria R. Zapatero-Osorio, Jeroen Bouwman, Vincent Coudé du Foresto, Mercedes Lopez-Morales, Ingo Mueller-Wodarg, Enric Pallé, Franck Selsis, Alessandro Sozzetti, Jean-Philippe Beaulieu, Thomas Henning, Michael Meyer, Giuseppina Micela, Ignasi Ribas, Daphne Stam, Mark Swain, Oliver Krause, Marc Ollivier, Emanuele Pace, Bruce Swinyard, Peter A.R. Ade, Nick Achilleos, Alberto Adriani, Craig B. Agnor, Cristina Afonso, Carlos Allende Prieto, Gaspar Bakos, Robert J. Barber, Michael Barlow, Peter Bernath, Bruno Bézard, Pascal Bordé, Linda R. Brown, Arnaud Cassan, Céline Cavarroc, Angela Ciaravella, Charles Cockell, Athéna Coustenis, Camilla Danielski, Leen Decin, Remco De Kok, Olivier Demangeon, Pieter Deroo, Peter Doel, Pierre Drossart, Leigh N. Fletcher, Matteo Focardi, Francois Forget, Steve Fossey, Pascal Fouqué, James Frith, Marina Galand, Patrick Gaulme, Jonay I. González Hernández, Davide Grassi, Matt J. Griffin, Ulrich Grözinger, Manuel Guedel, Pactrick Guio, Olivier Hainaut, Robert Hargreaves, Peter H. Hauschildt, Kevin Heng, David Heyrovsky, Ricardo Hueso, Pat Irwin, Lisa Kaltenegger, Patrick Kervella, David Kipping, Geza Kovacs, Antonino La Barbera, Helmut Lammer, Emmanuel Lellouch, Giuseppe Leto, Mercedes Lopez Morales, Miguel A. Lopez Valverde, Manuel Lopez-Puertas, Christophe Lovi, Antonio Maggio, Jean-Pierre Maillard, Jesus Maldonado Prado, Jean-Baptiste Marquette, Francisco J. Martin-Torres, Pierre Maxted, Steve Miller, Sergio Molinari, David Montes, Amaya Moro-Martin, Olivier Mousis, Napoléon Nguyen Tuong, Richard Nelson, Glenn S. Orton, Eric Pantin, Enzo Pascale, Stefano Pezzuto, Ennio Poretti, Raman Prinja, Loredana Prisinzano, Jean-Michel Réess, Ansgar Reiners, Benjamin Samuel, Jorge Sanz Forcada, Dimitar Sasselov, Giorgio Savini, Bruno Sicardy, Alan Smith, Lars Stixrude, Giovanni Strazzulla, Gautam Vasisht, Sandrine Vinatier, Serena Viti, Ingo Waldmann, Glenn J. White, Thomas Widemann, Roger Yelle, Yuk Yung, Sergey Yurchenko
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- Journal:
- Proceedings of the International Astronomical Union / Volume 6 / Issue S276 / October 2010
- Published online by Cambridge University Press:
- 10 November 2011, pp. 359-370
- Print publication:
- October 2010
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The science of extra-solar planets is one of the most rapidly changing areas of astrophysics and since 1995 the number of planets known has increased by almost two orders of magnitude. A combination of ground-based surveys and dedicated space missions has resulted in 560-plus planets being detected, and over 1200 that await confirmation. NASA's Kepler mission has opened up the possibility of discovering Earth-like planets in the habitable zone around some of the 100,000 stars it is surveying during its 3 to 4-year lifetime. The new ESA's Gaia mission is expected to discover thousands of new planets around stars within 200 parsecs of the Sun. The key challenge now is moving on from discovery, important though that remains, to characterisation: what are these planets actually like, and why are they as they are?
In the past ten years, we have learned how to obtain the first spectra of exoplanets using transit transmission and emission spectroscopy. With the high stability of Spitzer, Hubble, and large ground-based telescopes the spectra of bright close-in massive planets can be obtained and species like water vapour, methane, carbon monoxide and dioxide have been detected. With transit science came the first tangible remote sensing of these planetary bodies and so one can start to extrapolate from what has been learnt from Solar System probes to what one might plan to learn about their faraway siblings. As we learn more about the atmospheres, surfaces and near-surfaces of these remote bodies, we will begin to build up a clearer picture of their construction, history and suitability for life.
The Exoplanet Characterisation Observatory, EChO, will be the first dedicated mission to investigate the physics and chemistry of Exoplanetary Atmospheres. By characterising spectroscopically more bodies in different environments we will take detailed planetology out of the Solar System and into the Galaxy as a whole.
EChO has now been selected by the European Space Agency to be assessed as one of four M3 mission candidates.
Fabrication, chemical etching, and compressive strength of porous biomimetic SiC for medical implants
- Carmen Torres-Raya, David Hernandez-Maldonado, Joaquin Ramirez-Rico, Carmen Garcia-Gañan, Antonio R. de Arellano-Lopez, Julian Martinez-Fernandez
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- Journal of Materials Research / Volume 23 / Issue 12 / December 2008
- Published online by Cambridge University Press:
- 31 January 2011, pp. 3247-3254
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- December 2008
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BioSiC is a biomimetic SiC-based ceramic material fabricated by Si melt infiltration of carbon preforms obtained from wood. The microstructure of bioSiC mimics that of the wood precursor, which can be chosen for tailored properties. When the remaining, unreacted Si is removed, a SiC material with interconnected porosity is obtained. This porous bioSiC is under study for its use as a medical implant material. We have successfully fabricated bioSiC from Sipo wood and studied the kinetics of Si removal by wet etching. The results suggest that the reaction is diffusion-limited, and the etch rate follows a t−0.5 law. The etching rate is found to be anisotropic, which can be explained attending to the anisotropy of the pore distribution. The compressive strength was studied as a function of etching time, and the results show a quadratic dependence with density. In the attainable range of densities, the strength is similar or better than that of human bone.
Myrtillocactus (cactaceae): botanical, agronomic, physicochemical and chemical characteristics of fruits
- David Hernández-López, Fabrice Vaillant, Rosalia Reynoso-Camacho, Salvador-Horacio Guzman-Maldonado
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Introduction. In Mexico, the Myrtillocactus fruit production levels are substantial, yet fruits are often under-used. Although the focus of interest is on their potential as food colourings, the fruits deserve more attention for their other food properties but information on their physico-chemical composition is scarce. To offer a baseline for the development of Myrtillocactus cultivation, we reviewed the information so far available. Botanical description. Four Myrtillocactus species have been identified and reported in the literature. They differ in shape, colour and other phenotypic characteristics. In Mexico, the predominant species is M. geometrizans, but M. schenckii also grows abundantly throughout the arid and semi-arid lands of the country. Cytological analyses performed on M. geometrizans showed that the plant is diploid (2n = 22). Agronomic aspects. Myrtillocactus species belong to the Cactaceae family. Because of their Crassulacean acid metabolism, they are able to grow in the arid and semi-arid highlands of Mexico. Myrtillocactus species have been propagated asexually by explants or cloning. Under controlled conditions, in vitro micropropagation from apical and basal explants gives rise to high yields. For cultivation, attention should be paid especially to minimum winter temperatures. Description of fruits and biochemical characterisation. The edible fruit is globular, with diameters reaching 1.5 cm. The pulp is gel-like, ranging in colour from glowing red to bluish. Chemical characterisation has mainly focused on betalain compounds, the predominant ones of which are betanin and betaxanthins. Contents are reported to be about 2.3 mg betalain·100 g–1of pulp. Colour appears to be more stable than for red beets. Human consumption and commercial importance. In the production season (June to September), the fruits are found in all public markets in the states where they are grown. They are eaten either fresh or in processed forms. The commercialisation of the fruit is restricted mainly to rural production areas in certain states of Mexico. Conclusions. Our review establishes that published information on Myrtillocactus species is scarce and incomplete. The plant is under-utilised, despite its nutritional properties and commercial potential. Because they adapt easily to severely dry conditions, the Myrtillocactus species merit much more research.