Mobility and International Collaboration: Case of the Mexican Scientific Diaspora

We use a data set of Mexican researchers working abroad that are included in the Mexican National System of Researchers (SNI). Our diaspora sample includes 479 researchers, most of them holding postdoctoral positions in mainly seven countries: USA, Great Britain, Germany, France, Spain, Canada and Brazil. Their research output and impact is explored in order to determine their patterns of production, mobility and scientific collaboration as compared with previous studies of the SNI researchers in the periods 1991–2001 and 2003–2009. Our findings confirm that mobility has a strong impact on their international scientific collaboration. We found no substantial influence among the researchers that got their PhD degrees abroad from those trained in Mexican universities. There are significant differences among the areas of knowledge studied: biological sciences, physics and engineering have better production and impact rates than mathematics, geosciences, medicine, agrosciences, chemistry, social sciences and humanities. We found a slight gender difference in research production but Mexican female scientists are underrepresented in our diaspora sample. These findings would have policy implications for the recently established program that will open new academic positions for young Mexican scientists.     

The Geography of Gender Inequality

Reducing gender inequality is a major policy concern worldwide, and one of the Sustainable Development Goals. However, our understanding of the magnitude and spatial distribution of gender inequality results either from limited-scale case studies or from national-level statistics. Here, we produce the first high resolution map of gender inequality by analyzing over 689,000 households in 47 countries. Across these countries, we find that male-headed households have, on average, 13% more asset wealth and 303% more land for agriculture than do female-headed households. However, this aggregate global result masks a high degree of spatial heterogeneity, with bands of both high inequality and high equality apparent in countries and regions of the world. Further, areas where inequality is highest when measured by land ownership generally are not the same areas that have high inequality as measured by asset wealth. Our metrics of gender inequality in land and wealth are not strongly correlated with existing metrics of poverty, development, and income inequality, and therefore provide new information to increase the understanding of one critical dimension of poverty across the globe.     

Science policies: How should science funding be allocated? An evolutionary biologists’ perspective

In an ideal world, funding agencies could identify the best scientists and projects and provide them with the resources to undertake these projects. Most scientists would agree that in practice, how funding for scientific research is allocated is far from ideal and likely compromises research quality. We, nine evolutionary biologists from different countries and career stages, provide a comparative summary of our impressions on funding strategies for evolutionary biology across eleven different funding agencies. We also assess whether and how funding effectiveness might be improved. We focused this assessment on 14 elements within four broad categories: (a) topical shaping of science, (b) distribution of funds, (c) application and review procedures, and (d) incentives for mobility and diversity. These comparisons revealed striking among‐country variation in those elements, including wide variation in funding rates, the effort and burden required for grant applications, and the extent of emphasis on societal relevance and individual mobility. We use these observations to provide constructive suggestions for the future and urge the need to further gather informed considerations from scientists on the effects of funding policies on science across countries and research fields.     

Sex Differences in Mathematics and Reading Achievement Are Inversely Related: Within- and Across-Nation Assessment of 10 Years of PISA Data

We analyzed one decade of data collected by the Programme for International Student Assessment (PISA), including the mathematics and reading performance of nearly 1.5 million 15 year olds in 75 countries. Across nations, boys scored higher than girls in mathematics, but lower than girls in reading. The sex difference in reading was three times as large as in mathematics. There was considerable variation in the extent of the sex differences between nations. There are countries without a sex difference in mathematics performance, and in some countries girls scored higher than boys. Boys scored lower in reading in all nations in all four PISA assessments (2000, 2003, 2006, 2009). Contrary to several previous studies, we found no evidence that the sex differences were related to nations’ gender equality indicators. Further, paradoxically, sex differences in mathematics were consistently and strongly inversely correlated with sex differences in reading: Countries with a smaller sex difference in mathematics had a larger sex difference in reading and vice versa. We demonstrate that this was not merely a between-nation, but also a within-nation effect. This effect is related to relative changes in these sex differences across the performance continuum: We did not find a sex difference in mathematics among the lowest performing students, but this is where the sex difference in reading was largest. In contrast, the sex difference in mathematics was largest among the higher performing students, and this is where the sex difference in reading was smallest. The implication is that if policy makers decide that changes in these sex differences are desired, different approaches will be needed to achieve this for reading and mathematics. Interventions that focus on high-achieving girls in mathematics and on low achieving boys in reading are likely to yield the strongest educational benefits.     

Chewing over physiology integration

An important challenge for both students and teachers of physiology is to integrate the different areas in which physiological knowledge is didactically divided. In developing countries, such an issue is even more demanding, because budget restrictions often affect the physiology program with laboratory classes being the first on the list when it comes to cuts in expenses. With the aim of addressing this kind of problem, the graduate students of our department organized a physiology summer course offered to undergraduate students. The objective was to present the different physiological systems in an integrated fashion. The strategy pursued was to plan laboratory classes whose experimental results were the basis for the relevant theoretical discussions. The subject we developed to illustrate physiology integration was the study of factors influencing salivary secretion.     

Species abundance and asymmetric interaction strength in ecological networks

The strength of interactions among species in a network tends to be highly asymmetric. We evaluate the hypothesis that this asymmetry results from the distribution of abundance among species, so that species interactions occur randomly among individuals. We used a database on mutualistic and antagonistic bipartite quantitative interaction networks. We show that across all types of networks asymmetry was correlated with abundance, so that rare species were asymmetrically affected by their abundant partners, while pairs of interacting abundant species tended to exhibit more symmetric, reciprocally strong effects. A null model shows that abundance provides a sufficient explanation of the asymmetry structure in some networks, but suggests the role of additional factors in others. Although not universal, our hypothesis holds for a substantial fraction of networks analyzed here, and should be considered as a null model in all studies aimed at evaluating the ecological and evolutionary consequences of species interactions.     

Countries with Higher Levels of Gender Equality Show Larger National Sex Differences in Mathematics Anxiety and Relatively Lower Parental Mathematics Valuation for Girls

Despite international advancements in gender equality across a variety of societal domains, the underrepresentation of girls and women in Science, Technology, Engineering, and Mathematics (STEM) related fields persists. In this study, we explored the possibility that the sex difference in mathematics anxiety contributes to this disparity. More specifically, we tested a number of predictions from the prominent gender stratification model, which is the leading psychological theory of cross-national patterns of sex differences in mathematics anxiety and performance. To this end, we analyzed data from 761,655 15-year old students across 68 nations who participated in the Programme for International Student Assessment (PISA). Most importantly and contra predictions, we showed that economically developed and more gender equal countries have a lower overall level of mathematics anxiety, and yet a larger national sex difference in mathematics anxiety relative to less developed countries. Further, although relatively more mothers work in STEM fields in more developed countries, these parents valued, on average, mathematical competence more in their sons than their daughters. The proportion of mothers working in STEM was unrelated to sex differences in mathematics anxiety or performance. We propose that the gender stratification model fails to account for these national patterns and that an alternative model is needed. In the discussion, we suggest how an interaction between socio-cultural values and sex-specific psychological traits can better explain these patterns. We also discuss implications for policies aiming to increase girls’ STEM participation.     

The importance of globalisation in driving the introduction and establishment of alien species in Europe

Understanding the role of globalisation in promoting introduction and establishment of alien species is an important step towards successful management of biological invasions. We aimed to quantify the taxon‐dependent association of globalisation with the introduction and establishment of alien species in Europe. The availability of the KOF index of globalisation that measures all economic, social and political dimensions of global connectivity enables a study of this factor. Based on an extensive database of alien species, we used model selections based on the Akaike information criterion and hierarchical partitioning to identify the importance of globalisation in predicting the number of all introduced species and established species of ten mainly terrestrial taxa in countries across Europe. The association of globalisation with alien species establishment varied depending on taxon type. While the gross domestic product (GDP) of countries was a strong predictor for all but one taxon, globalisation was also found to be an important predictor for three taxa including those of high (e.g. insects) and low mobility (e.g. magnoliophyta). Globalisation explained 3.1 to 22% independently, and 5.5 to 35% jointly with other variables, of among‐country variations in the number of established alien species. The effect of globalisation on the distribution of all introduced species is not substantially different from that on the established alien species. This study highlights how globalisation among habitat availability and environmental conditions can determine the patterns of alien species introduction and establishment across Europe. The results also emphasise the varying degree of importance between different taxa. Knowledge of the relative significance of various pathways with regard to different taxa is important for correctly focusing efforts to reduce the spread of these species.     

Fertility effects of family planning programs: a methodological review.

This paper reviews and compares the methodologies of some 70 investigations of the effect of family planning programs on fertility levels. Differences among the studies include variations in questions asked, research methods used, program type investigated, and made of program action assumed. Programs can affect fertility by providing means of fertility control, education, legitimation, incentives/disincentives or any combination of these but the actual effect of these modes is unclear. Comparison is usually made between the effects on fertility of a program as a whole and a hypothetical estimate of what fertility rates would have been without the program. This hypothetical estimate is in fact not subject to empirical measurement, and a variety of methods have been developed largely to attack this methodological problem. The article compares the characteristics of several methods and provides a matrix comparing their strength, limitations and applications. The methods discussed include: 1) decomposition of change which identifies several factors affecting changes in crude birth rate; 2) correspondence between program activity and fertility trends over time to across areas or groups, which often takes close statistical association as evidence of causality; 3) matching studies, which try to remove the influence of nonprogram factors by controlling the characteristics of the subject; 4) experimental and control areas, comparing presumably similar groups with and without family planning programs; 5) multiple regression across areal units which provides some information on areal trends but requires extensive data for many statistical areas; 6) calculation of national effects of births averted among acceptors; and 7) simulation, which compares data to mathematical projection models, such as the TABRAP/CONVERSE and POPSIM models. No one method is best but certain methods are best to answer certain questions. All of the methods have difficulty establishing actual causality between the program studied and fertility trends and ruling out alternative explanations. Recent studies encouraged by the U.N. Population Division are seeking cross-method and cross-program evaluation.     

On euthanasia: exploring psychological meaning and attitudes in a sample of Mexican physicians and medical students

Euthanasia has become the subject of ethical and political debate in many countries including Mexico. Since many physicians are deeply concerned about euthanasia, due to their crucial participation in its decision and implementation, it is important to know the psychological meaning that the term 'euthanasia' has for them, as well as their attitudes toward this practice. This study explores psychological meaning and attitudes toward euthanasia in 546 Mexican subjects, either medical students or physicians, who were divided into three groups: a) beginning students, b) advanced students, and c) physicians. We used the semantic networks technique, which analyzed the words the participants associated with the term 'euthanasia'. Positive psychological meaning, as well as positive attitudes, prevailed among advanced students and physicians when defining euthanasia, whereas both positive and negative psychological meaning together with more ambivalent attitudes toward euthanasia predominated in beginning students. The findings are discussed in the context of a current debate on a bill proposing active euthanasia in Mexico City.     

Detecting behavioural changes in human movement to inform the spatial scale of interventions against COVID-19

On March 23 2020, the UK enacted an intensive, nationwide lockdown to mitigate transmission of COVID-19. As restrictions began to ease, more localized interventions were used to target resurgences in transmission. Understanding the spatial scale of networks of human interaction, and how these networks change over time, is critical to targeting interventions at the most at-risk areas without unnecessarily restricting areas at low risk of resurgence. We use detailed human mobility data aggregated from Facebook users to determine how the spatially-explicit network of movements changed before and during the lockdown period, in response to the easing of restrictions, and to the introduction of locally-targeted interventions. We also apply community detection techniques to the weighted, directed network of movements to identify geographically-explicit movement communities and measure the evolution of these community structures through time. We found that the mobility network became more sparse and the number of mobility communities decreased under the national lockdown, a change that disproportionately affected long distance connections central to the mobility network. We also found that the community structure of areas in which locally-targeted interventions were implemented following epidemic resurgence did not show reorganization of community structure but did show small decreases in indicators of travel outside of local areas. We propose that communities detected using Facebook or other mobility data be used to assess the impact of spatially-targeted restrictions and may inform policymakers about the spatial extent of human movement patterns in the UK. These data are available in near real-time, allowing quantification of changes in the distribution of the population across the UK, as well as changes in travel patterns to inform our understanding of the impact of geographically-targeted interventions.     

Evaluating Sex and Gender Competencies in the Medical Curriculum: A Case Study

BackgroundSex and gender differences exist in the manifestation and prevalence of many conditions and diseases. Yet many clinician training programs neglect to integrate this information across their curricula.ObjectiveThis study aimed to measure the sex and gender medical knowledge of medical students enrolled in a program without an explicit directive to integrate sex and gender differences across a block system of core subjects.MethodsA forced-choice instrument consisting of 35 multiple-choice and true or false questions was adapted from an evaluation tool used in the European Curriculum in Gender Medicine held at Charité Hospital, Berlin, in September 2010.ResultsFourth-year (response rate 93%) and second-year (response rate 70%) students enrolled in Mayo Medical School completed the instrument. More than 50% of students in both classes indicated that topics related to sex and gender were covered in gynecology, cardiology, and pediatrics, and <20% of students indicated inclusion of such topics in nephrology, neurology, and orthopedics. More than twice as many second-year students indicated that topics dealing with sex and gender were included in immunology course material compared with fourth-year students. A consensus of written comments indicated that concepts of sex and gender-based medicine need to be embedded into existing curriculum, with an emphasis on clinically relevant information.ConclusionsAlthough this study represents only one medical school in the United States, information regarding sex and gender aspects of medicine is not consistently included in this curriculum without an explicit directive. These results can provide guidance for curriculum improvement to train future physicians.     

More than Half of High School Students Report Disordered Eating: A Cross Sectional Study among Norwegian Boys and Girls

Disordered eating and eating disorders are of great concern due to their associations with physical and mental health risks. Even if adolescence has been identified as the most vulnerable time for developing disordered eating, few studies have used a broad spectrum of criteria to investigate the prevalence of disordered eating among high school students of both genders, in different programs of study, nor assessed correlates of disordered eating among this important target group. The purposes of this study were therefore to investigate the prevalence and correlates of disordered eating among both male and female high school students in sport-, general and vocational programs. A comprehensive questionnaire was completed by 2,451 students (98.7%), aged 15–17 years. The total prevalence of disordered eating was 54.9%, with 64.3% among girls and 45.0% among boys (p<0.001). The highest prevalence of disordered eating was found among vocational students (60.7%), followed by students in general programs (49.8%) and sport students (38.3%) (p<0.001). Female gender, school program (vocational and general), overweight/obesity and weight regulation were positively associated with disordered eating. The high prevalence indicates the importance of tailored prevention efforts directed at high school students, particularly in vocational programs. Furthermore, a smaller girls–boys ratio than expected indicates that the efforts to identify and manage disordered eating among high school students should include both genders.     

Exploring Taiwanese and Turkish high school students’ conceptions of learning biology

The purpose of this study is to compare the conceptions of learning biology (COLB) of Taiwanese and Turkish high school students. In addition, it was investigated whether there is a gender difference in students’ COLB in both countries. The COLB questionnaire was implemented in both countries and students’ COLB were identified. A total of 562 Taiwanese and 546 Turkish high school students participated. The results indicated that the COLB questionnaire was valid and reliable for assessing Taiwanese and Turkish high school students’ COLB. And, a significant difference was found between Taiwanese and Turkish students’ mean scores in four learning conceptions as memorising, calculating and practicing, increasing one’s knowledge and seeing in a new way. Moreover, differences were found between the mean scores of Taiwanese female and male students in memorising and understanding; however, there were no mean differences between Turkish female and male students in COLB factors. In addition, analyses of cross-country comparison with respect to gender in the factors of COLB, there was a statistically significant difference between students’ male and female students of Turkey and Taiwan on the some categories of COLB scores. The research findings were considered for both countries and a discussion was conducted on the reasons for the differences.     

Asymmetry patterns across the distribution range: does the species matter?

An important question in evolutionary ecology is whether different populations across a species range, from core to periphery, experience different levels of stress. The estimation of developmental instability has been proposed as a useful tool for quantifying the degree of environmental and genetic stress that individuals experience during their development. Fluctuating asymmetry, the unsigned difference between the two sides of a bilaterally symmetrical trait, has been suggested to reflect the levels of developmental instability in a population. As such, it has been proposed as a useful tool for estimating changes in developmental instability and in stress response in populations across a range of environmental conditions. Recent studies focusing mostly on birds have detected increasing fluctuating asymmetry from core to periphery across the distribution range, suggesting that peripheral populations may experience higher levels of environmental and/or genetic stress. Most of these comparisons were done for single taxa across a single gradient. However, different species are predicted to respond differently to environmental shifts across the range. We compared asymmetry patterns in wing morphology in populations of two Euchloe butterfly species across their opposing ranges in Israel. Contrary to the patterns observed in birds across the same gradient, bilateral asymmetry did not increase or shift towards the periphery in either of the butterfly species. If fluctuating asymmetry in these traits reflects levels of stress, these results may partly reflect the fact that the range of these two butterfly species is limited by the distribution of their host plant, rather than by abiotic environmental variables. In addition, developing pierids can diapause during harsh seasons and can persist in resource‐rich patches, thus minimizing the environmental stress perceived by developing individuals. We conclude that accounting for differences in species’ life histories and range‐limiting factors is necessary in order to better predict patterns of developmental instability across spatial and environmental gradients. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 81 , 313–324.     

Predicting global population connectivity and targeting conservation action for snow leopard across its range

Movements of individuals within and among populations help to maintain genetic variability and population viability. Therefore, understanding landscape connectivity is vital for effective species conservation. The snow leopard is endemic to mountainous areas of central Asia and occurs within 12 countries. We assess potential connectivity across the species’ range to highlight corridors for dispersal and genetic flow between populations, prioritizing research and conservation action for this wide‐ranging, endangered top‐predator. We used resistant kernel modeling to assess snow leopard population connectivity across its global range. We developed an expert‐based resistance surface that predicted cost of movement as functions of topographical complexity and land cover. The distribution of individuals was simulated as a uniform density of points throughout the currently accepted global range. We modeled population connectivity from these source points across the resistance surface using three different dispersal scenarios that likely bracket the lifetime movements of individual snow leopard: 100 km, 500 km and 1000 km. The resistant kernel models produced predictive surfaces of dispersal frequency across the snow leopard range for each distance scenario. We evaluated the pattern of connectivity in each of these scenarios and identified potentially important movement corridors and areas where connectivity might be impeded. The models predicted two regional populations, in the north and south of the species range respectively, and revealed a number of potentially important connecting areas. Discrepancies between model outputs and observations highlight unsurveyed areas of connected habitat that urgently require surveying to improve understanding of the global distribution and ecology of snow leopard, and target land management actions to prevent population isolation. The connectivity maps provide a strong basis for directed research and conservation action, and usefully direct the attention of policy makers.     

Genetic structure of Partamona helleri (Apidae, Meliponini) from Neotropical Atlantic rainforest

Stingless bees of the genus Partamona are distributed from southern Mexico to southern Brazil. This genus has been subject to different approaches to solve questions concerning general biology, taxonomy, systematics and biogeography, but population studies applying molecular techniques are inexistent. We analyzed the genetic structure of P. helleri across its geographic distribution along the coastal Atlantic tropical rainforest in Brazil. Ten mtDNA haplotypes were observed in 47 colonies of P. helleri of which some were exclusive and others shared among geographic sub-groups. Statistical analysis showed high genetic differentiation between geographic areas sampled. Fragmentation of the Atlantic forest during Pleistocene glaciations is discussed as a possible cause of the present haplotype distribution and frequency.     

Facial symmetry in young girls and boys from a slum and a control area of Ankara,Turkey

Deviations from perfect symmetry in paired traits of otherwise bilateral symmetrical organisms are thought to reflect developmental quality, especially the ability to resist environmental perturbations early in ontogeny. It is well established that poor environmental conditions increase developmental instability (DI) as reflected by measurements of fluctuating asymmetry. In humans, there is evidence that DI relates to numerous fitness components, and studies have found that perceptions of facial attractiveness for example are positively correlated with measurements of facial symmetry. Here we report the data on measurements of facial symmetry of 503 Turkish senior year high school students aged 17 to 18 years, of whom 133 males and 117 females were recruited from a slum district of ?entepe in Ankara (Group 1), and 131 males and 122 females from three high schools in wealthy central urban areas (Group 2). Digital images were used to assess the degree of facial asymmetry as measured from seven paired traits and calculated as a composite score. Facial asymmetry of participants in Group 1 (slum district) was significantly higher than that of participants in Group 2 (urban areas). Moreover, males in Group 1 were found to have higher facial asymmetry than females, while no sex difference was observed in Group 2. We conclude that poor living conditions have an influence on DI in humans, which manifests itself in the form of facial asymmetry, and that this might be particularly true for males.     

Interplay of host specificity and biogeography in the population structure of a cosmopolitan endoparasite: microsatellite study of Ligula intestinalis (Cestoda)

Organisms with wide geographical or phenotypic diversity often constitute assemblages of genetically distinct species or lineages. Within parasites, an emergence of host-specific lineages is assumed to create such cryptic variability; however, empirical evaluation of these processes is scarce. Here, we analyse populations of a parasite with a complex life cycle, wide host spectrum and global distribution, with the aim to reveal factors underlying the evolution of host- or geography-dependent lineages. Using 15 microsatellite loci, deep genetic distances were observed between populations from distant geographical areas. On the local scale, host-mediated genetic structure was found among sympatric samples. Two lineages differing in the spectrum of infected hosts co-occurred in the Euro-Mediterranean area, and two distinct lineages were recovered from Lake Tana in Ethiopia. Although sampled across several host taxa and multiple localities, a lack of marked genetic structure was seen in the populations belonging to one of the European lineages. Only weak genetic differentiation between sympatric samples from two host species was found. Complexity of the parasite life-cycle contributed to such a stratified pattern. Differences in the immune response between fish hosts were suggested as the factor diversifying the populations locally; conversely, high mobility of the parasite due to migration with its bird (definitive) host were assessed to homogenize populations across the area of distribution. However, despite the high mobility, large bodies of salt water prevent the parasite from long-distance migrations, as was demonstrated in an example of the Mediterranean Sea which represented an effective barrier to gene flow.