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Influence of poverty concerns on demand for healthier processed foods: A field experiment in Mexico City

Marrit Van den Berg Jason Donovan (2023, [Artículo])

Living in poverty can present cognitive biases that exacerbate constraints to achieving healthier diets. Better diets could imply food choice upgrades within certain food categories, such as electing processed foods with an improved nutritional profile. This study evaluated the influence of monetary and health concerns on the willingness to pay (WTP) for healthier processed foods in a low-income section of Mexico City. We employed priming techniques from the scarcity literature, which are applied for the first time to healthier food purchasing behaviours in low-income settings. Our predictions are based on a dual system framework, with choices resulting from the interaction of deliberative and affective aspects. The WTP was elicited through a BDM mechanism with 423 participants. Results showed that induced poverty concerns reduced the valuations of one of the study's healthier food varieties by 0.17 standard deviations. The latter effect did not differ by income level. The WTP for a healthier bread product but one with relatively high sugar and fat content was reduced by induced poverty concerns only among certain consumers without bread purchasing restrictions (78% of the sample). Potential mechanisms were assessed through regression analysis and structural equation modelling. The relationship between poverty concerns and WTP was mediated by increased levels of stress. While we could not rule out impact on cognitive load, it was not deemed a mediator in this study. Our findings signal that improvements in economic and psychological well-being among low-income consumers may aid to increase their demand for healthier processed foods.

Healthier Diets Poverty Psychology Dual System Model CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA DIET POVERTY PSYCHOLOGY STRESS WILLINGNESS TO PAY

Ecología trófica del pez damisela Stegastes acapulcoensis (Pomacentridae) en un arrecife de Bahías de Huatulco, Oaxaca

Trophic ecology of the damselfish Stegastes acapulcoensis (Pomacentridae) in a reef of Bahías de Huatulco, Oaxaca

Diana Alejandra Vela Espinosa (2023, [Tesis de maestría])

Se caracterizó la alimentación y la morfología del sistema alimentario de la damisela Stegastes acapulcoensis en la bahía La Entrega, Oaxaca, con el objetivo de determinar su espectro trófico. En agosto de 2022, se recolectaron 30 ejemplares de S. acapulcoensis en el período de mayor actividad de alimentación, utilizando arpones caseros y equipo de buceo SCUBA. Las muestras se fijaron con formol al 5% para preservar sus tejidos y facilitar la identificación de presas. Cada ejemplar se sometió a un análisis biométrico detallado, incluyendo mediciones de peso total, longitud total y longitud estándar. Los componentes alimentarios se identificaron y clasificaron en nueve categorías, con las algas destacando como el componente más consumido, seguido del detritus y los invertebrados. El Índice de Importancia Relativa (%IIR) confirmó la importancia de estos componentes en la dieta de S. acapulcoensis. El análisis del espectro trófico reveló que esta especie es un depredador generalista, con una dieta que abarca una diversidad moderada de componentes alimentarios. Además, se encontró una correlación positiva significativa entre el peso de los individuos y su consumo de algas, lo que sugiere una relación entre el tamaño y los hábitos alimentarios. La morfología del sistema alimentario, incluyendo el aparato mandibular y las placas faríngeas, apoyó la adaptación de S. acapulcoensis a una dieta herbívora oportunista. Los dientes incisivos y las características de las placas faríngeas indicaron una especialización en la captura y procesamiento de alimentos vegetales. En conjunto, estos hallazgos proporcionaron una visión completa de la ecología alimentaria de S. acapulcoensis en La Entrega, resaltando la importancia de las algas en su dieta y su capacidad para ajustarse a diferentes fuentes de alimento. Además, se amplió nuestra comprensión de la relación entre la morfología y la ecología alimentaria en los peces damisela, lo que contribuye al conocimiento de estos ecosistemas marinos y su gestión.

The feeding and morphology of the food system of the damselfish Stegastes acapulcoensis in La Entrega Bay, Oaxaca, was characterized to determine its trophic spectrum. In August 2022, 30 specimens of S. acapulcoensis were collected during the period of peak feeding activity, using homemade harpoons and SCUBA diving equipment. Samples were fixed with 5% formalin to preserve their tissues and facilitate prey identification. Each specimen was subjected to detailed biometric analysis, including measurements of total weight, total length, and standard length. Food components were identified and classified into nine categories, with algae standing out as the most consumed component, followed by detritus and invertebrates. The Relative Importance Index (%IIR) confirmed the importance of these components in the diet of S. acapulcoensis. Trophic spectrum analysis revealed that this species is a generalist predator, with a diet encompassing a moderate diversity of food components. In addition, a significant positive correlation was found between the weight of individuals and their consumption of algae, suggesting a relationship between size and feeding habits. The morphology of the food system, including the mandibular apparatus and pharyngeal plates, supported the adaptation of S. acapulcoensis to an opportunistic herbivore. The incisor teeth and pharyngeal plate characteristics indicated a specialization in the capture and processing of plant foods. Taken together, these findings provided a comprehensive view of the feeding ecology of S. acapulcoensis in La Entrega, highlighting the importance of algae in its diet and its ability to adjust to different food sources. In addition, our understanding of the relationship between morphology and feeding ecology in damselfish was expanded, contributing to the knowledge of these marine ecosystems and their management.

Dieta, ecología, morfología mandibular Diet, ecology, jaw morphology BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA OTRAS ESPECIALIDADES DE LA BIOLOGÍA OTRAS OTRAS

El génesis de la distopía. Elementos distópicos en el cuento “La última guerra” de Amado Nervo

Javier Martínez Javalois (2023, [Otro, Trabajo terminal, especialidad])

55 páginas. Especialización en Literatura Mexicana del Siglo XX.

Esta investigación recibió el apoyo del Sistema Nacional de Posgrados (SNP) del Consejo Nacional de Humanidades, Ciencias y Tecnologías (México). CONAHCYT.

El presente estudio tiene como objetivo principal analizar el cuento “La última guerra” (1906) de Amado Nervo (1870-1919), partiendo desde la literatura de ciencia ficción, en particular desde la temática de la distopía. En el cuento “La última guerra”, el autor evidencia el conflicto que se da entre la humanidad y una sociedad animal por el caos que ha provocado el dominio del hombre sobre el mundo y sobre las criaturas; ante la imposibilidad de estas últimas para revertir esta condición a lo largo del tiempo, se gesta una animadversión que desencadena una batalla entre ambas especies: los humanos y los animales. Este trabajo pretende mostrar el cambio en la sociedad ficcionalizada por Amado Nervo, el surgimiento y alcance máximo como sociedad y su crisis partiendo desde el punto inicial de la conflagración. La animadversión que acontece entre humanos y animales en un mundo cuya posesión está en disputa brinda elementos para un análisis de la antes mencionada sociedad distópica. A mi modo de ver, el acercamiento al análisis desde esta perspectiva resulta útil para entender cómo operan la desigualdad y la estratificación social en la estructura narrativa y el tiempo propuestos por Nervo en la ficción.

Nervo, Amado, 1870-1919--Criticism and interpretation. Dystopias in literature. Human-animal relationships--Fiction. Aggressive behavior in animals--Fiction. Distopías en la literatura. Relaciones hombre-animal en el arte. Animales en la literatura. PQ7297.N5 HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS TEORÍA, ANÁLISIS Y CRÍTICA LITERARIAS

Voter´´´'s dilemma between honest and competent candidates in the 2018 elections in Mexico and Brazil

José Daniel Sousa Oliva (2023, [Artículo, Artículo])

This article is dedicated to understanding and explaining the electoral dilemma “Dishonest, but competent” and “Honest, but incompetent” in the elections of legislators, governors and municipal presidents in 2018 in Mexico and Brazil. The research questions that guided the investigation are: Why are there voters in Mexico and Brazil who vote for “dishonest” candidates? And how do the voters of those countries decide their vote in the face of this dilemma? The theoretical approach of this work is Social Psychology through two analytical tools: the Funnel of Causality and the Tripartite Model of Attitudes. The methodology is mixed, quantitative and qualitative, using statistical models with data from the international surveys World Values Survey and Comparative Studies of Electoral Systems, as well as the application of Focus Groups in the distance modality. In this way, four categories of voter are proposed: moralist, moralist-moderate, pragmatic-moderate and pragmatic. The arguments of this work are: first, that regardless of cultural differences, there is an “affective voter” “non-rational” who makes decisions based on emotions and intuition, demonstrating that the affective components of attitudes are more relevant than the cognitive ones in electoral choice; second, that voting for “dishonest” candidates is determined under a greater influence of “short-term factors” such as candidate characteristics and short-term events rather than “long-term factors” such as party loyalties and ideology.

politics, electoral behavior, political culture, democracy, public opinion. política, comportamiento electoral, cultura política, democracia, opinión pública. CIENCIAS SOCIALES CIENCIAS SOCIALES

Voter´´´'s dilemma between honest and competent candidates in the 2018 elections in Mexico and Brazil

José Daniel Sousa Oliva (2023, [Artículo, Artículo])

This article is dedicated to understanding and explaining the electoral dilemma “Dishonest, but competent” and “Honest, but incompetent” in the elections of legislators, governors and municipal presidents in 2018 in Mexico and Brazil. The research questions that guided the investigation are: Why are there voters in Mexico and Brazil who vote for “dishonest” candidates? And how do the voters of those countries decide their vote in the face of this dilemma? The theoretical approach of this work is Social Psychology through two analytical tools: the Funnel of Causality and the Tripartite Model of Attitudes. The methodology is mixed, quantitative and qualitative, using statistical models with data from the international surveys World Values Survey and Comparative Studies of Electoral Systems, as well as the application of Focus Groups in the distance modality. In this way, four categories of voter are proposed: moralist, moralist-moderate, pragmatic-moderate and pragmatic. The arguments of this work are: first, that regardless of cultural differences, there is an “affective voter” “non-rational” who makes decisions based on emotions and intuition, demonstrating that the affective components of attitudes are more relevant than the cognitive ones in electoral choice; second, that voting for “dishonest” candidates is determined under a greater influence of “short-term factors” such as candidate characteristics and short-term events rather than “long-term factors” such as party loyalties and ideology.

politics, electoral behavior, political culture, democracy, public opinion. política, comportamiento electoral, cultura política, democracia, opinión pública. CIENCIAS SOCIALES CIENCIAS SOCIALES

Vibrissa growth rate in California sea lions based on environmental and isotopic oscillations

MARTHA PATRICIA ROSAS HERNANDEZ (2018, [Artículo])

Pinniped vibrissae provide information on changes in diet at seasonal and annual scales; however, species-specific growth patterns must first be determined in order to interpret these data. In this study, a simple linear model was used to estimate the growth rate of vibrissae from adult female California sea lions (Zalophus californianus) from San Esteban Island in the Gulf of California, Mexico. The δ15N and δ13C values do not display a marked oscillatory pattern that would permit direct determination of the time period contained in each vibrissa; thus, time (age) was calculated in two ways: 1) based on the correlation between the observed number of peaks (Fourier series) in the δ15N profile and the length of each vibrissa, and 2) through direct comparison with the observed number of peaks in the δ15N profile. Cross-correlation confirmed that the two peaks in the δ15N profile reflected the two peaks in the chlorophyll-a concentration recorded annually around the island. The mean growth rate obtained from the correlation was 0.08 ± 0.01 mm d-1, while that calculated based on the observed number of peaks was 0.10 ± 0.05 mm d-1. Both are consistent with the rates reported for adult females of other otariid species (0.07 to 0.11 mm d-1). Vibrissa growth rates vary by individual, age, sex, and species; moreover, small differences in the growth rate can result in significant differences over the time periods represented by the isotopic signal. Thus, it is important to assess this parameter on a species-by-species basis. © 2018 Rosas-Hernández et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

carbon, nitrogen, animal, California, chemistry, diet, female, island (geological), Mexico, Otariidae, physiology, Animals, California, Carbon Isotopes, Diet, Female, Islands, Mexico, Nitrogen Isotopes, Sea Lions BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA INMUNOLOGÍA INMUNOLOGÍA

Vibrissa growth rate in California sea lions based on environmental and isotopic oscillations

MARTHA PATRICIA ROSAS HERNANDEZ (2018, [Artículo])

Pinniped vibrissae provide information on changes in diet at seasonal and annual scales; however, species-specific growth patterns must first be determined in order to interpret these data. In this study, a simple linear model was used to estimate the growth rate of vibrissae from adult female California sea lions (Zalophus californianus) from San Esteban Island in the Gulf of California, Mexico. The δ15N and δ13C values do not display a marked oscillatory pattern that would permit direct determination of the time period contained in each vibrissa; thus, time (age) was calculated in two ways: 1) based on the correlation between the observed number of peaks (Fourier series) in the δ15N profile and the length of each vibrissa, and 2) through direct comparison with the observed number of peaks in the δ15N profile. Cross-correlation confirmed that the two peaks in the δ15N profile reflected the two peaks in the chlorophyll-a concentration recorded annually around the island. The mean growth rate obtained from the correlation was 0.08 ± 0.01 mm d-1, while that calculated based on the observed number of peaks was 0.10 ± 0.05 mm d-1. Both are consistent with the rates reported for adult females of other otariid species (0.07 to 0.11 mm d-1). Vibrissa growth rates vary by individual, age, sex, and species; moreover, small differences in the growth rate can result in significant differences over the time periods represented by the isotopic signal. Thus, it is important to assess this parameter on a species-by-species basis. © 2018 Rosas-Hernández et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

carbon, nitrogen, animal, California, chemistry, diet, female, island (geological), Mexico, Otariidae, physiology, Animals, California, Carbon Isotopes, Diet, Female, Islands, Mexico, Nitrogen Isotopes, Sea Lions CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA

Trophic ecology of Mexican Pacific harbor seal colonies using carbon and nitrogen stable isotopes

MARICELA JUAREZ RODRIGUEZ (2020, [Artículo])

There is limited information that provides a comprehensive understanding of the trophic ecology of Mexican Pacific harbor seal (Phoca vitulina richardii) colonies. While scat analysis has been used to determine the diet of some colonies, the integrative characterization of its feeding habits on broader temporal and spatial scales remains limited. We examined potential feeding grounds, trophic niche width, and overlap, and inferred the degree of dietary specialization using stable carbon and nitrogen isotope ratios (δ13C and δ15N) in this subspecies. We analyzed δ13C and δ15N on fur samples from pups collected at five sites along the western coast of the Baja California Peninsula, Mexico. Fur of natal coat of Pacific harbor seal pups begins to grow during the seventh month in utero until the last stage of gestation. Therefore pup fur is a good proxy for the mother's feeding habits in winter (∼December to March), based on the timing of gestation for the subspecies in this region. Our results indicated that the δ13C and δ15N values differed significantly among sampling sites, with the highest mean δ15N value occurring at the southernmost site, reflecting a well-characterized north to south latitudinal 15N-enrichment in the food web. The tendency identified in δ13C values, in which the northern colonies showed the most enriched values, suggests nearshore and benthic-demersal feeding habits. A low variance in δ13C and δ15N values for each colony (<1‰) and relatively small standard ellipse areas suggest a specialized foraging behavior in adult female Pacific harbor seals in Mexican waters. © 2020 Juárez-Rodríguez et al.

carbon, delta carbon 13, delta nitrogen 15, isotope, nitrogen, unclassified drug, carbon, nitrogen, Article, correlational study, feeding behavior, latitude, Mexico, nonhuman, organism colony, Pinnipedia, population abundance, species richness, troph BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) BIOLOGÍA ANIMAL (ZOOLOGÍA)

High quality diet improves lipid metabolic profile and breeding performance in the blue-footed booby, a long-lived seabird

ERICK GONZALEZ MEDINA (2018, [Artículo])

Understanding the role of diet in the physiological condition of adults during reproduction and hence its effect on reproductive performance is fundamental to understand reproductive strategies in long-lived animals. In birds, little is known about the influence of the quality of food consumed at the beginning of the reproductive period and its short-term effects on reproductive performance. To assess the role of diet in the physiological condition of female blue-footed booby, Sula nebouxii (BFBO), during reproduction we evaluated whether individual differences in diet (assessed by using δ13C and δ15N values of whole blood from female birds and muscle tissue of the principal prey species) prior to egg laying and during incubation influenced their lipid metabolic profile (measured as triglyceride levels and C:N ratio) and their reproductive performance (defined by laying date, clutch size and hatching success). Females with higher δ15N values in their blood during the courtship and incubation periods had a higher lipid metabolic profile, earlier laying date, greater clutch size (2–3 eggs) and higher hatching success. Females that laid earlier and more eggs (2–3 eggs) consumed more Pacific anchoveta (Cetengraulis mysticetus) and Pacific thread herring (Opisthonema libertate) than did other females. These two prey species also had high amounts of lipids (C:N ratio) and caloric content (Kcal/g fresh weight). The quality of food consumed by females at the beginning of reproduction affected their physiological condition, as well as their short-term reproductive performance. Our work emphasizes the importance of determining the influence of food quality during reproduction to understand the reproductive decisions and consequences in long-lived animals. © 2018 González-Medina et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

nitrogen 15, triacylglycerol, lipid, animal experiment, Article, breeding, carbon nitrogen ratio, clutch size, controlled study, courtship, diet, egg laying, female, food intake, hatching, lipid metabolism, muscle tissue, nonhuman, prey, reproduction CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA

Protein retention assessment of four levels of poultry by-product substitution of fishmeal in rainbow trout (Oncorhynchus mykiss) diets using stable isotopes of nitrogen (δ15N) as natural tracers

DANIEL BADILLO ZAPATA (2014, [Artículo])

This is second part from an experiment where the nitrogen retention of poultry by-product meal (PBM) compared to fishmeal (FM) was evaluated using traditional indices. Here a quantitative method using stable isotope ratios of nitrogen (δ15N values) as natural tracers of nitrogen incorporation into fish biomass is assessed. Juvenile rainbow trout (Oncorhynchus mykiss) were fed for 80 days on isotopically distinct diets in which 0, 33, 66 and 100% of FM as main protein source was replaced by PBM. The diets were isonitrogenous, isolipidic and similar in gross energy content. Fish in all treatments reached isotopic equilibrium by the end of the experiment. Two-source isotope mixing models that incorporated the isotopic composition of FM and PBM as well as that of formulated feeds, empirically derived trophic discrimination factors and the isotopic composition of fish that had reached isotopic equilibrium to the diets were used to obtain a quantitative estimate of the retention of each source of nitrogen. Fish fed the diets with 33 and 66% replacement of FM by PBM retained poultry by-product meal roughly in proportion to its level of inclusion in the diets, whereas no differences were detected in the protein efficiency ratio. Coupled with the similar biomass gain of fishes fed the different diets, our results support the inclusion of PBM as replacement for fishmeal in aquaculture feeds. A re-feeding experiment in which all fish were fed a diet of 100% FM for 28 days indicated isotopic turnover occurred very fast, providing further support for the potential of isotopic ratios as tracers of the retention of specific protein sources into fish tissues. Stable isotope analysis is a useful tool for studies that seek to obtain quantitative estimates of the retention of different protein sources. © 2014 Badillo et al.

nitrogen 15, nitrogen, protein intake, animal behavior, animal experiment, animal food, animal tissue, aquaculture, Article, biomass, controlled study, energy metabolism, food composition, juvenile animal, nonhuman, poultry by product meal, protein a CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA