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In this paper we describe all invariant complex Dirac structures with constant real index on a maximal flag manifold in terms of the roots of the Lie algebra which defines the flag manifold. We also completely classify these structures under the action of B-transformations. [ABSTRACT FROM AUTHOR]

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Copyright of Quaderns de l'Institut Català d'Antropologia is the property of Institut Catala d'Antropologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We characterize those real flag manifolds that can be endowed with invariant generalized almost complex structures. We show that no G M 2 -maximal real flag manifolds admit integrable invariant generalized almost complex structures. We give a concrete description of the generalized complex geometry on the maximal real flags of type B 2 , G 2 , A 3 , and D l with l ≥ 5 , where we prove that the space of invariant generalized almost complex structures under invariant B-transformations is homotopy equivalent to a torus and we classify all invariant generalized almost Hermitian structures on them. [ABSTRACT FROM AUTHOR]

Objectives: Cohort variation in adult height expresses both the impact of socio‐economic change on human biology in a wide temporal perspective and social inequalities within populations. We aimed to test the use of joinpoint regressions to identify periods in which changes in height trends were statistically significant. Methods: Data correspond to the height recorded in Madrid City (Spain) for 65 313 conscripts between 1936 and 1974 (cohorts from 1915 to 1953), a period of social and political turmoil. Secular trends in height were analyzed in eight districts with contrasting socio‐economic conditions, grouped in two categories, lower‐class and middle‐ and upper‐class. Trends in height were evaluated by quadratic regressions and by joinpoint regressions to identify the cut‐off years when trends changed significantly. Results: Height increased in both socio‐economic categories of districts, more among conscripts from the lower‐class ones. However, results clearly show differences in trends according to district of residence. Whereas the increase in height in conscripts from the middle‐ and upper‐class districts was steady, it was slower in those from the lower classes, with declines in height during the Civil War and first years of the Franco dictatorship. Conclusions: Joinpoint analysis reveals the association between urban living conditions and adult height, and that the disparities intensified during critical historical periods of Spain. [ABSTRACT FROM AUTHOR]

Objectives: Plasticity in the growth of body segments between populations has been researched in relation to migration, temporal change and high‐altitude studies. We study the within population variation in body segments, thus controlling for some of the environmental and genetic differences that could be at play in between populations studies. We test a version of the thrifty phenotype hypothesis, where the growth of head‐trunk and hand are prioritized due to their functional significance over height and leg growth. Materials and methods: A total of 3913 Guatemalan, rural, semi‐urban and urban, Maya and Ladino children 6 to 15 years old were studied. Height, sitting height, leg length, and metacarpal length were studied in relation to three proxies for living conditions: height‐ and leg length‐for‐age, and maternal education. Estimation statistics and null hypothesis significance testing were used to analyze the data. Results: Metatarsal length and sitting height values were higher than height and leg length respectively. Relative metacarpal length was conserved across height‐for‐age groups. Females were less affected than males for metacarpal length and sitting height, but more affected for leg length. Conclusion: Our results agree with the thrifty phenotype hypothesis, where metacarpal and sitting height growth would be prioritized over height and leg length due to greater functional significance. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated a negative, significant impact on birthweight associated with the current economic crisis in Spain, which has also been reported for other European countries. Effects by parity are not known. Our aim is to compare the trends in low birthweight (LBW) by parity in Spain from 1996 to 2016. Using the National Vital Statistics data, joinpoint regression analysis was used to identify the time periods of significant changes in the prevalence of LBW by parity. Adjusted relative risk (RR) of LBW by year of birth was calculated in order to confirm that the time trend differences in LBW by parity were independent of possible confounders. The prevalence of LBW among live births to primiparous increased from 5.12% to 6.87% in 2008 and then stabilised at maximum values, while among live births to multiparous LBW increased from 3.96% to a maximum of 5.20% and then significantly reduced. Trends in adjusted RR of LBW by parity confirm that primiparous and multiparous were affected differently by the economic crisis. Older, nulliparous women may have felt more biosocial pressure to reproduce during the economic crisis, compared to women who were already mothers. This biosocial pressure may have increased the risks for LBW. [ABSTRACT FROM AUTHOR]

We show that the partition function on a generalised conifold Cm,n with (...) crepant resolutions can be equivalently computed on the compound du Val singularity Am+n-1 × C with a unique crepant resolution. [ABSTRACT FROM AUTHOR]

Background: There is growing evidence of the impact of the current European economic crisis on health. In Spain, since 2008, there have been increasing levels of impoverishment and inequality, and important cuts in social services. Aim: The objective is to evaluate the impact of the economic crisis on underweight at birth in Spain. Method: Trends in underweight at birth were examined between 2003 and 2012. Underweight at birth is defined as a singleton, term neonatal weight lesser than -2 SD from the median weight at birth for each sex estimated by the WHO Standard Growth Reference. Using data from the Statistical Bulletin of Childbirth, 2 933 485 live births born to Spanish mothers have been analysed. Descriptive analysis, seasonal decomposition analysis and crude and adjusted logistic regression including individual maternal and foetal variables as well as exogenous economic indicators have been performed. Results and conclusions: Results demonstrate a significant increase in the prevalence of underweight at birth from 2008. All maternal-foetal categories were affected, including those showing the lowest prevalence before the crisis. In the full adjusted logistic regression, year-on-year GDP per capita remains predictive on underweight at birth risk. Previous trends in maternal socio-demographic profiles and a direct impact of the crisis are discussed to explain the trends described. [ABSTRACT FROM AUTHOR]

For most of our history as a species, maternal constraint was the main environmental factor affecting biological status at birth. However, the great increase in medical intervention in the20th Century coincided first with an extraordinary reduction in perinatal mortality and later with an increase in preterm and low birth-weight babies. Herein, we analyze these temporary trends in neonate biology in Spain, according to early viability (1980-2010) and ethnic variability (1996-2010). The aim of this study is to evaluate the interaction between maternal and medical environmental constraints affecting the biology of birth and to understand the observed ethnic differences and secular trends. All single births in Spain between 1980 and 2010 are included. Following descriptive analysis, logistic regression analysis was applied to evaluate the effect of secular trends, mode of delivery and mother's origin on birth outcome after adjustment for other maternal bio-cultural factors. Results highlighted that mean birth weight decreased and prematurity increased in still births, live births and deaths before one day. In regard to ethnic differences, while there were no secular trends in weight by gestational age in the Spanish newborns, there was an increase among the newborns of foreign mothers. Spanish mothers experienced an increasing and higher frequency of low birth weight, while foreigners had an increasing and higher frequency of prematurity. Both groups, however, shared temporal reduction in gestational age, and although this was less marked in foreigners, it suggests a common trend related to medical care and increasing obstetric interventions [ABSTRACT FROM AUTHOR]

Based on previous findings showing both better birth outcomes in migrant than in Spanish women and different rates of medical intervention according to mother's origin, we hypothesize that mode of delivery decisions to solve similar problems differ according to ethnic origin. Ethnic differences for maternal characteristics, medical intervention, and mode of delivery were evaluated in 16,589 births from a Maternity Hospital in Madrid (Spain). Multinomial logistic regression analysis was used to evaluate the effect of mother's ethnic origin on the mode of delivery, adjusting for mother's age, parity, gestational age, birth weight, and epidural anesthesia. Compared with the Spanish mothers, the risk of having a Caesarean section is significantly higher in Latin Americans and significantly lower for the Chinese. Both low birth weight and macrosomic deliveries are at higher risk for Caesarean section. The interventionist system characterizing Spain is being extended to all ethnic groups and, at the same time, different medical interventions are applied to similar problems depending on women's ethnic origin. Obstetric interventions might be contributing to the increasing trend of low birth weight and late preterm/early full term deliveries (37-38 weeks) observed in Spain. Behavioral and cultural values of the women and of the health care providers may contribute to systematic differences in labor management and mode of delivery. [ABSTRACT FROM AUTHOR]

Objectives: Previous studies generally agree that in Homo sapiens births without medical intervention occur mostly at night, although with a less accentuated pattern than in other primate species. The present study has three main objectives: (a) to establish the hourly pattern of births in a modern medicalized population, (b) to explore the association between the hour of birth and maternal and fetal variables and mode of delivery, and (c) to evaluate the risk for medical intervention at different hours of the day. Methods: The hourly distribution of 25,779 deliveries at the 'La Paz' Madrid University Maternity Hospital (Spain) has been analyzed. Two different multivariate analyses have been used to evaluate, respectively, the relationships between maternal and fetal characteristics and the type of birth and hour of delivery. Results: The increasing of unnecessary hospital interventions seems to have transformed the nocturnal pattern of birth into a diurnal one and may be contributing to the rise of preterm and low birth weight deliveries, reducing their probability of being breastfeed, and eliminating or transforming emotional and social support. Immigrant women present a higher frequency of the nocturnal pattern of delivery than their Spanish counterparts. Conclusions: The predominant nocturnal pattern of birth seems to have disappeared in a Spanish highly medicalized population. However, the hallmark of primate nocturnal deliveries is evident when multiple births, malpresentation, Caesarean sections, and vaginal interventions are excluded. Possible consequences of diurnal birth include reduced infant-mother bonding, breast feeding, and later life reductions to health. Am. J. Hum. Biol., 2012. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A sample of 842 rural women from Morocco (Amizmiz, Marrakech) was used to examine the relationship between a number of biosocial variables and fertility patterns. For women still in their reproductive years there were significant correlations between family size and woman's age, age at marriage and years of marriage. Among women with completed families, those with early age at marriage ceased childbearing about 10 years before reaching menopause, while women who married later continued to bear children until the end of their fertile life. [ABSTRACT FROM PUBLISHER]

Objectives: Among the ancestral characteristics of the primate group to which Homo sapiens belongs we find a pattern of daytime physical activity, but one notable exception is birthing which usually begins with night‐time labor. In populations with a moderate or high level of medicalized labor, there is evidence that the medical preferences interfere with the underlying biological mechanism for the circadian pattern of human birth. Methods: This study analyses the hourly patterns of 4,599 single live births in the House of Maternity in Madrid between 1887 and 1892, a period of very limited obstetric intervention and without the influence of artificial lighting. In order to determine the influence of natural light on labor, two periods of maximum and minimum light have been established around the summer and winter solstices of the years in question. Results: A clear circadian pattern of births emerges, with very early morning and early morning births dominating, and a sharp drop from midday until nightfall. The hourly distribution on both solstices follows this pattern, but with a clear peak shift: in winter, there is a greater concentration of deliveries in the early morning, whereas in the summer, the highest concentration is between 8 and 12 in the morning. Conclusions: The results confirm that non‐intervened human birth has a clear diurnal cycle, with a higher incidence of deliveries in the early morning or morning. The shift in distribution during the winter and summer solstices seems to confirm the effect of light on the labor process. Am. J. Hum. Biol. 26:707–709, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

ABSTRACT Objectives Among the ancestral characteristics of the primate group to which Homo sapiens belongs we find a pattern of daytime physical activity, but one notable exception is birthing which usually begins with night-time labor. In populations with a moderate or high level of medicalized labor, there is evidence that the medical preferences interfere with the underlying biological mechanism for the circadian pattern of human birth. Methods This study analyses the hourly patterns of 4,599 single live births in the House of Maternity in Madrid between 1887 and 1892, a period of very limited obstetric intervention and without the influence of artificial lighting. In order to determine the influence of natural light on labor, two periods of maximum and minimum light have been established around the summer and winter solstices of the years in question. Results A clear circadian pattern of births emerges, with very early morning and early morning births dominating, and a sharp drop from midday until nightfall. The hourly distribution on both solstices follows this pattern, but with a clear peak shift: in winter, there is a greater concentration of deliveries in the early morning, whereas in the summer, the highest concentration is between 8 and 12 in the morning. Conclusions The results confirm that non-intervened human birth has a clear diurnal cycle, with a higher incidence of deliveries in the early morning or morning. The shift in distribution during the winter and summer solstices seems to confirm the effect of light on the labor process. Am. J. Hum. Biol. 26:707-709, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]