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This paper discusses the type of professional learning that international academic mobility makes possible during a PhD program. The conceptual approach used Pierre Bourdieu's field theory, which allows analyzing PhD students as 'newcomer' members who bet on mobility under the idea of "illusio." The methodology used was qualitative. The information was obtained through semi-structured interviews with twenty-four new researchers who studied in four prestigious PhD programs in education and history in Mexico. The findings demonstrate that mobility fosters relationships with peers abroad, makes it easier to learn to do research, favors the reconversion of capital within the scientific field, and offers practical knowledge related to the need to publish results in order to achieve international recognition.

In this article, I put Carlos Reygadas' prize-winning art film, Stellet Licht, to use for Law and Film purposes. Stellet Licht (or Silent Light) is the first film made in the medieval German/Prussian dialect, Plautdietsch (or Low German), and filmed in an Old Order (very conservative) Mennonite colony in Mexico. Viewers of Stellet Licht must be prepared to be contemplative because the film often eschews dialogue or action in favour of contemplation. This fictitious film invites us to contemplate a heterosexual love triangle and provides a novel site for thinking about how law and patriarchy can unconsciously work in our lives. When we do the contemplative work invited by the film, we not only see law differently, but we can also imagine miraculous reconciliation between people. [ABSTRACT FROM AUTHOR]

Objectives Mexico has a rapidly aging population at risk for cognitive impairment. Social and leisure activities may protect against cognitive decline in older adults. The benefits of these behaviors may vary by patterns of cognitive impairment. The objectives of this study were to identify latent states of cognitive functioning, model the incidence of transitions between these states, and investigate how social and leisure activities were associated with state transitions over a 6-year period in Mexican adults aged 60 and older. Methods We performed latent transition analyses to identify distinct cognitive statuses in the 2012 and 2018 waves of the Mexican Health and Aging Study (N = 9,091). We examined the transition probabilities between these states and their associations with social and leisure activities. Results We identified 4 cognitive statuses at baseline: normal cognition (43%), temporal disorientation (30%), perceptual-motor function impairment (7%), and learning and memory impairment (20%). Various social and leisure activities were associated with reduced odds of death and disadvantageous cognitive transitions, as well as increased odds of beneficial transitions. Discussion Mapping the effects of popular social and leisure activities onto common patterns in cognitive functioning may inform the development of more enjoyable and effective health-protective behavioral interventions. [ABSTRACT FROM AUTHOR]

How does early social experience affect children's inferences and exploration? Following prior work on children's reasoning in pedagogical contexts, this study examined U.S. children with less experience in formal schooling and Yucatec Mayan children whose early social input is predominantly observational. In Experiment 1, U.S. 2-year-olds (n = 77) showed more restricted exploration of a toy following a pedagogical demonstration than an interrupted, accidental, or no demonstration (baseline). In Experiment 2, Yucatec Mayan and U.S. 2-year-olds (n = 66) showed more restricted exploration following a pedagogical than an observational demonstration, while only Mayan children showed more restriction with age. These results suggest that although schooling is not a necessary precursor for sensitivity to pedagogy, early social experience may influence children's inferences and exploration in pedagogical contexts.

Maize is a staple food of smallholder farmers living in highland regions up to 4,000 m above sea level worldwide. Mexican and South American highlands are two major highland maize growing regions, and population genetic data suggest the maize's adaptation to these regions occurred largely independently, providing a case study for convergent evolution. To better understand the mechanistic basis of highland adaptation, we crossed maize landraces from 108 highland and lowland sites of Mexico and South America with the inbred line B73 to produce F1 hybrids and grew them in both highland and lowland sites in Mexico. We identified thousands of genes with divergent expression between highland and lowland populations. Hundreds of these genes show patterns of convergent evolution between Mexico and South America. To dissect the genetic architecture of the divergent gene expression, we developed a novel allele–specific expression analysis pipeline to detect genes with divergent functional cis- regulatory variation between highland and lowland populations. We identified hundreds of genes with divergent cis- regulation between highland and lowland landrace alleles, with 20 in common between regions, further suggesting convergence in the genes underlying highland adaptation. Further analyses suggest multiple mechanisms contribute to this convergence in gene regulation. Although the vast majority of evolutionary changes associated with highland adaptation were region specific, our findings highlight an important role for convergence at the gene expression and gene regulation levels as well. [ABSTRACT FROM AUTHOR]

Constraining the degree of preservation of a meteoritic signature within an impact structure provides vital insights in the complex pathways and processes that occur during and after an impact cratering event, providing information on the fate of the projectile. The IODP-ICDP Expedition 364 drilling recovered a ∼829 m continuous core (M0077A) of impactites and basement rocks within the ∼200-km diameter Chicxulub impact structure peak ring. No highly siderophile element (HSE) data have been reported for any of the impact melt rocks of this drill core to date. Previous work has shown that most Chicxulub impactites contain less than 0.1% of a chondritic component. Only few impact melt rock samples in previous drill cores recovered from the Chicxulub might contain such a signal. Therefore, we analyzed impact melt rock and suevite samples, as well as pre-impact lithologies of the Chicxulub peak ring, with a focus on the HSE concentrations and Re–Os isotopic compositions. Similar to the concentrations of the other major and trace elements, those of the moderately siderophile elements (Cr, Co, Ni) of impact melt rock samples primarily reflect mixing between a mafic (dolerite) and felsic (granite) components, with the incorporation of carbonate material in the upper impact melt rock unit (from 715.60 to 747.02 meters below seafloor). The HSE concentrations of the impact melt rocks and suevites are generally low (<39 ppt Ir, <96 ppt Os, <149 ppt Pt), comparable to the values of the average upper continental crust, yet three impact melt rock samples exhibit an enrichment in Os (125–410 ppt) and two of them also in Ir (250–324 ppt) by one order of magnitude relative to the other investigated samples. The 187Os/188Os ratios of the impact melt rocks are highly variable, ranging from 0.18 to 2.09, probably reflecting heterogenous target rock contributions to the impact melt rocks. The significant amount of mafic dolerite (mainly ∼20–60% and up to 80–90%), which is less radiogenic (187Os/188Os ratio of 0.17), within the impact melt rocks makes an unambiguous identification of an extraterrestrial admixture challenging. Granite samples have unusually low 187Os/188Os ratios (0.16 on average), while impact melt rocks and suevites broadly follow a mixing trend between upper continental crust and chondritic/mantle material. Only one of the investigated samples of the upper impact melt rock unit could also be interpreted in terms of a highly diluted (∼0.01–0.05%) meteoritic component. Importantly, the impact melt rocks and pre-impact lithologies were affected by post-impact hydrothermal alteration processes, probably remobilizing Re and Os. The mafic contribution, explaining the least radiogenic 187Os/188Os values, is rather likely. The low amount of meteoritic material preserved within impactites of the Chicxulub impact structure may result from a combination of the assumed steeply-inclined trajectory of the Chicxulub impactor (enhanced vaporization, and incorporation of projectile material within the expansion plume), the impact velocity, and the volatile-rich target lithologies. [ABSTRACT FROM AUTHOR]

This study examines how Mexican-origin women construct and navigate racialized identities in a postindustrial northern border community during a period of prolonged restrictive immigration and immigrant policies, and it considers mechanisms by which responses to racialization may shape health. This grounded theory analysis involves interviews with 48 Mexican-origin women in Detroit, Michigan, who identified as being in the first, 1.5, or second immigrant generation. In response to institutions and institutional agents using racializing markers to assess their legal status and policing access to health-promoting resources, women engaged in a range of strategies to resist being constructed as an "other." Women used the same racializing markers or symbols of (il)legality that had been used against them as a malleable set of resources to resist processes of racialization and to form, preserve, and affirm their identities. These responses include constructing an authorized immigrant identity, engaging in immigration advocacy, and resisting stigmatizing labels. These strategies may have different implications for health over time. Findings indicate the importance of addressing policies that promulgate or exacerbate racialization of Mexican-origin communities and other communities who experience growth through migration. Such policies include creating pathways to legalization and access to resources that have been invoked in racialization processes, such as state-issued driver's licenses. [ABSTRACT FROM AUTHOR]

This article studies the importance of international academic mobility in doctoral education in Mexico from the perspective of the coordinators of doctoral programs in education and history. We analyze official documents and interview doctoral program coordinators in several disciplines to show the existence of interest in promoting mobility through public policy, as well as the programs' implementation of strategies to encourage this activity. The importance attached to international academic mobility is related to the certainty that such experience is fundamental in learning the craft of research, regardless of the discipline. We also show the presence of contradictions in government discourse on internationalization and the inconsistency that has characterized government support for internationalization. The result is the uncertain future of the practices of doctoral education. [ABSTRACT FROM AUTHOR]

How does early social experience affect children's inferences and exploration? Following prior work on children's reasoning in pedagogical contexts, this study examined U.S. children with less experience in formal schooling and Yucatec Mayan children whose early social input is predominantly observational. In Experiment 1, U.S. 2-year-olds (n = 77) showed more restricted exploration of a toy following a pedagogical demonstration than an interrupted, accidental, or no demonstration (baseline). In Experiment 2, Yucatec Mayan and U.S. 2-year-olds (n = 66) showed more restricted exploration following a pedagogical than an observational demonstration, while only Mayan children showed more restriction with age. These results suggest that although schooling is not a necessary precursor for sensitivity to pedagogy, early social experience may influence children's inferences and exploration in pedagogical contexts. [ABSTRACT FROM AUTHOR]

Objective: The global epidemics of type 2 diabetes and obesity have been attributed to the interaction between lifestyle changes and genetic predisposition to these diseases. We compared the prevalences of type 2 diabetes and obesity in Mexican Pima Indians, presumed to have a high genetic predisposition to these diseases, to those in their non-Pima neighbors, both of whom over a 15-year period experienced a transition from a traditional to a more modern lifestyle.Research Design and Methods: Prevalence of diabetes, impaired fasting glucose, impaired glucose tolerance, and obesity in Mexican Pimas (n = 359) and non-Pima Mexicans (n = 251) were determined in 2010 using methods identical to those used in 1995.Results: During this 15-year period, age-adjusted diabetes prevalence was unchanged in Pima men (5.8% in 1995 vs. 6.1% in 2010) yet increased in non-Pima men from 0.0 to 8.6% (P < 0.05). Diabetes prevalence tended to increase in both Pima women (9.4 vs. 13.4%) and non-Pima women (4.8 vs. 9.5%). Age-adjusted prevalence of obesity increased significantly in all groups (6.6 vs. 15.7% in Pima men; 8.5 vs. 20.5% in non-Pima men; 18.9. vs 36.3% in Pima women; 29.5 vs. 42.9% in non-Pima women).Conclusions: Type 2 diabetes prevalence increased between 1995 and 2010 in non-Pima men, and to a lesser degree in women of both groups, but it did not increase in Pima men. Prevalence of obesity increased among Pimas and non-Pimas of both sexes. These changes occurred concomitantly with an environmental transition from a traditional to a more modernized lifestyle. [ABSTRACT FROM AUTHOR]

Objective: To focus on the rationale and methods of the Maycoba Project. Methods: Study population included Mexican Pima Indians (MPI) and Blancos aged ≥20-years, living in the village of Maycoba and surrounding area. Surveys in 1995 and 2010 included a medical history, biochemical and anthropometric measurements. Additionally, socioeconomic, physical activity, and dietary interviews were conducted. The 2010 study incorporated investigations on type 2 diabetes (T2D) and obesity-associated genetic alleles and human-environment changes. Results: The study results are limited to demographic data and description of the eligible and examined sample. Conclusions: This study may yield important information on T2D and obesity etiology in a traditional population exposed to environmental changes. [ABSTRACT FROM AUTHOR]

Background: In 1995, a study was conducted to identify the effects of traditional and westernized environments on the prevalence of type 2 diabetes in Pima Indians (Pimas) in Mexico and the United States. The study concluded that the more traditional lifestyle in Mexico had a protective effect against this metabolic disorder. In the ensuing 15 years, the environmental circumstances of the Mexican Pimas changed, and a follow-up study was conducted to determine the role environmental change plays in the development of diabetes in this genetically susceptible population. A major element of environmental transition relates to land-use and land-cover (LULC) changes that could affect physical activity and promote an obesogenic environment. This study examined changes in the region's LULC to determine whether there have been transitions in agricultural land use and urbanization that would be consistent with a more sedentary lifestyle. Changes were assessed from 1994 aerial photographs and 2007 satellite images. Results: The land-cover analysis showed that mixed vegetation and dense trees cover most of the study area. It suggested a rural environment that includes a low percentage of impermeable areas, and it indicated that the area experiencing human intervention covers 7% of the total area. The land-use-change findings showed a decrease or no change in agricultural or ranching areas and a decrease in farmland due to reforestation or revegetation. Three variables from the land-use-change analysis were examined as proxies for lifestyle change: urban development, dwelling-unit density, and variation in the road network. Two of the measures--the amount of urbanization and the number and density of dwelling units--showed increases, most notably in the town of Maycoba. There were only minor changes in the road network: most of the road segments are short and concentrated in Maycoba where most of the buildings, points of interest (e.g., church, stores), and cars are located. Conclusions: The LULC in Maycoba and surrounding settlements had changed during the study period. LULC change was used as a proxy to examine lifestyle changes that can affect levels of physical activity. [ABSTRACT FROM AUTHOR]

We examined the association between context of entry into the United States and symptoms of depression in an older age Mexican-origin population. We found that context of entry was associated with the number of depressive symptoms reported in this population. Specifically, immigrants who arrived to the U.S. following the Mexican Revolution (1918-1928) reported significantly fewer depressive symptoms, and those who arrived following enactment of the Immigration Reform Control Act (1965-1994) reported significantly more symptoms of depression, compared to those who arrived in the Bracero era (1942-1964). These findings suggest that sociopolitical context at the time of immigration may be associated with long-term psychological well-being. They contribute to a growing body of literature that suggests that the context of immigration may have long-term implications for the health of immigrant populations. We discuss implications of our findings for understanding relationships between immigration policies and the health of Mexican immigrant populations. [ABSTRACT FROM AUTHOR]

Existing research rarely considers important ethnic subgroup variations in violent behaviors among Latino youth. Thus, their risk for severe violent behaviors is not well understood in light of the immense ethnic and generational diversity of the Latino population in the United States. Grounded in social control theory and cultural analyses of familism, we examine differences in the risk for severe youth violence, as well its associations with family cohesion, parental engagement, adolescent autonomy, household composition, and immigrant generation among Mexican (n = 1,594), Puerto Rican (n = 586), Cuban (n = 488), and non-Latino Black (n = 4,053), and White (n = 9,921) adolescents with data from the National Longitudinal Study of Adolescent Health. Results indicate a gradient of risk; White youth had the lowest risk for severe violence and Puerto Rican youth had the highest risk compared to all other racial/ethnic subgroups. Within-group analysis indicates that family factors are not universally protective or risk-inducing. While family cohesion decreased the risk of severe violence among all groups, parental engagement was associated with increased risk among Blacks and Whites, and adolescent autonomy was associated with increased risk among Puerto Ricans and Cubans. In addition, Cuban and White adolescents who lived in single parent households or who did not live with their parents, had higher risk for severe violent behaviors than their counterparts who lived in two parent households. Among Latinos, the association of immigrant generation was in opposite directions among Mexicans and Cubans. We conclude that family and immigration factors differentially influence risk for violence among Latino subgroups and highlight the significance of examining subgroup differences and developing intervention strategies that are tailored to the needs of each ethnic subgroup. [ABSTRACT FROM AUTHOR]

Gardens are an important part of the environment as they play multiple roles and are central to the lifestyle and economy of many communities. The investigators use qualitative methods to explore patterns and perceptions about changes in gardening and cultivation in the community of Maycoba, Mexico. Maycoba is home to a large community of Pima Indians, an Indigenous population genetically prone to diabetes. Pima Indians living in the United States have been shown to have an extremely high prevalence of diabetes, but the genetically comparable Pimas in Maycoba, Mexico, were found to have little diabetes in the early 1990s. The authors examine home gardens and other cultivation in the area as an element of a changing environment and lifestyle during the past 15 years. Methods include interviews and focus groups. Preliminary findings are presented in this paper. [ABSTRACT FROM AUTHOR]

The article explores the literacy practices a Mexican family values and its two children bring to school. With the complex background of the family, the author highlights the questions raised about the lives of other students from diverse backgrounds and the opportunities that literacy and schooling can provide for them. With the article, the author aims to provide teachers with recommendations to support children and families from diverse backgrounds. She stresses the need for parents to view themselves as partners in their child's learning.

Background Melasma is a common condition of Latino women that detracts from their quality of life (QOL). The prevalence and impact of melasma in Latino men is not well characterized. Aim To assess the prevalence of melasma and its association with QOL in Latino men from Mexico and Central America working in the USA. Methods The prevalence of melasma was assessed in three studies of Latino men: by direct examination in a study of 25 Latino poultry workers; by direct examination in a study of 54 Latino farm workers; and by examination of store-and-forward teledermatology images in a study of 300 Latino farm workers. QOL was assessed with a Spanish version of the Dermatology Life Quality Index (DLQI). Results The prevalence of melasma was 36.0%, 7.4%, and 14.0% in the three studies. The prevalence of melasma was greatest amongst those aged 31 years and older, who were from Guatemala, and who spoke an indigenous language. The presence of melasma was associated with higher DLQI scores, indicating a poorer QOL, in the poultry worker population. Conclusions Melasma is a common condition in Latino men and is associated with a poor QOL in some affected individuals. Clinicians should be aware that melasma may be a concern for their male Latino patients. Research on the association of skin conditions with QOL amongst minority men is needed. [ABSTRACT FROM AUTHOR]

The 31.6±0.3 Ma old Bufa del Diente alkali-syenite (NE Mexico) intruded a sequence of Cretaceous limestones with intercalated sub-horizontal chert layers. The cherts acted as aquifers that facilitated transport of brines and pegmatitic melts within the shallow-level (<1 kbar) contact-metamorphic aureole. Fluid-driven reactions between chert and marble wallrock, and the influx of late melts and various fluids gave rise to distinct chemical and isotopic signatures within the aquifer and across the zones of infiltration and fluid-driven reaction. Aqueous brines of magmatic origin produced thick wollastonite mantles around the chert layers. Wollastonite formation occurred at the expense of limestone and chert and generated CO2. This CO2-induced fluid unmixing into an aqueous brine and a low-density CO2-rich fluid, which was lost to the overlying marble where it oxidized organic matter and caused δ13C and δ18O shifts in a zone some 5–10 cm wide. After wollastonite formation, the chert aquifers were locally intruded by pegmatite veins carrying alkali feldspar, quartz, aegirine-augite, eudialyte, zircon, and apatite. Aqueous fluids that exsolved during crystallization of the pegmatite veins escaped along late cross-fractures and migrated along the inner and outer borders of the wollastonite margins. Chemical dispersion patterns of U, Al, Na + K, P, S, Fe, and REE across the chert-to-marble boundary and its metasomatic rims are shown by autoradiography and neutron-induced radiography. Scavenging of cations at mineralogical contacts and cation transport into the marbles occurred only on the mm to cm scale. Isotopic data for Pb and Sr across a simple metachert-marble boundary and for Pb, Sr, Nd, B, and Li across a metachert-pegmatite-marble sequence demonstrate the following: (1) The Pb and Sr isotopic signature of early fluids was buffered by the carbonate wallrock. Only late fluids, shielded from wallrock interaction by a wollastonite mantle, variably preserved a memory of their initial magmatic signature. (2) Since the Nd isotope signature of marble and chert is bound to calcite and clay minerals, systematic shifts to unradiogenic Nd in marble reflect loss of carbonate-bound Nd as the wollastonite margin is approached. Nd in the wollastonite margin is dominated by Nd originally bound to clay minerals. The later emplacement of the pegmatite, which carried the Nd isotope signature of its alkali-syenite source, had little effect on the Nd isotopic composition of the wollastonite rim. (3) Although the Li and B isotopic compositions reflect the alkali-syenite source, they are also affected by isotopic fractionation and partitioning between melt, fluid, and solids. [ABSTRACT FROM AUTHOR]

In this work, the chemical structural characterization of the erionite-type zeolite from Agua Prieta, Sonora, México, was performed on both pristine and Na, Ca, and Mg exchanged samples in order to identify the various modifications due to cation exchange. The samples investigated were those that showed the best behaviour of CO2 and CH4 adsorption at zero coverage levels and the higher values of surface area reported in our previous studies. According to the crystal-chemical formula (Na3.44K1.96Mg0.63Ca0.62)[Al8.21Si27.79O71.85]·29.63H2O, the pristine sample has been classified as erionite-Na. Morphological FE-SEM investigation performed on both pristine (ERIN) and Na-exchanged samples (ERINa3) showed a similar range of fiber diameters (27–37 nm). The chemical analyses of the ion-exchanged samples evidenced the upload of Ca and Mg following ion exchange with Na. Rietveld analysis results allowed the identification of the chemical structural modification caused by the ion exchange process, occurring mainly at the Ca1 site. [ABSTRACT FROM AUTHOR]