52 research outputs found

    Motor Development Interventions for Preterm Infants: A Systematic Review and Meta-analysis

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    CONTEXTS Preterm infants are at an increased risk of neurodevelopmental delay. Some studies report positive intervention effects on motor outcomes, but it is currently unclear which motor activities are most effective in the short and longer term. OBJECTIVE The aim of the study was to identify interventions that improve the motor development of preterm infants. DATA SOURCES An a priori protocol was agreed upon. Seventeen electronic databases from 1980 to April 2015 and gray literature sources were searched. STUDY SELECTION Three reviewers screened the articles. DATA EXTRACTION The outcome of interest was motor skills assessment scores. All data collection and risk of bias assessments were agreed upon by the 3 reviewers. RESULTS Forty-two publications, which reported results from 36 trials (25 randomized controlled trials and 11 nonrandomized studies) with a total of 3484 infants, met the inclusion criteria. A meta-analysis was conducted by using standardized mean differences on 21 studies, with positive effects found at 3 months (mean 1.37; confidence interval 0.48-2.27), 6 months (0.34; 0.11-0.57), 12 months (0.73; 0.20-1.26), and 24 months (0.28; 0.07-0.49). At 3 months, there was a large and significant effect size for motor-specific interventions (2.00; 0.28-3.72) but not generic interventions (0.33; -0.03 to -0.69). Studies were not excluded on the basis of quality; therefore, heterogeneity was significant and the random-effects model was used. LIMITATIONS Incomplete or inconsistent reporting of outcome measures limited the data available for meta-analysis beyond 24 months. CONCLUSIONS A positive intervention effect on motor skills appears to be present up to 24 months' corrected age. There is some evidence at 3 months that interventions with specific motor components are most effective

    Population Identifiability from Forensic Genetic Markers: Ancestry Variation in Latin America

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    The Combined DNA Index System (CODIS) loci are a standard microsatellite marker set widely used for distinguishing among individuals in forensic DNA identity testing for medico-legal casework in the United States and in other countries. In anthropological genetic research, CODIS markers have become an important tool for uses extending beyond case investigations to quantify ancestry proportions, reveals patterns of admixture and trace population histories. These investigations are especially prevalent in studies of Latin American population structure. Nevertheless, the accuracy of the ancestry estimates computed from the CODIS loci for highly admixed Latino populations has not been formally tested. Long-standing arguments have been made that small ancestry panels, including the CODIS loci specifically, are not suitable for ancestry inference in admixed populations, due to the high heterozygosity and limited number of the loci used. Recent studies on ancestry inference using the CODIS loci suggest that these do confer more information of population-level identifiability than recognized in forensic genetic scholarship and by the medico-legal community. Here, we formally test the ability of CODIS and CODIS-Proxy (e.g. high heterozygosity and individual identifiability loci) marker panels to accurately estimate admixture proportions of individuals, including a sample of Latinos with a wide range of ancestry proportions. Using the same individuals in order to make direct comparisons of the outcomes, we produce ancestry estimates from 1) a small CODIS/CODIS Proxy loci panel and 2) a robust and validated microsatellite ancestry informative panel. We find evidence (e.g. ρ = 0.80 to 0.88) that supports the use of CODIS/CODIS-Proxy loci to capture the general ancestry estimation trends of a sample. This finding is in line with what studies using CODIS on Latin American populations have found, in that the ancestry estimations generated by CODIS present trends supported by documented population histories (e.g. colonialism and population movements) and microevolutionary events (e.g. gene flow) in Latin America. However, the present study also highlights the limitations of CODIS for making individual-level inferences of ancestry, as the associated estimates for an acceptable level of statistical confidence (95%) are demonstrated here to be too broad to make any nuanced inferences regarding the individual’s actual ancestry composition

    An Admixture Approach to Trihybrid Ancestry Variation in the Philippines with Implications for Forensic Anthropology

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    In this study, we investigate, for the first time from a forensic anthropological perspective, the question of mixed ancestry estimation for modern Filipinos with geographic origins in the Philippines. We derive estimates of continental ancestry using craniometrics from four sources: a new documented collection of current forensic significance from the Manila North Cemetery; the Howells cranial series representing a sample of unclaimed individuals from Manila but said largely to originate from more remote areas, with dates of death before 1940; the Hanihara sample aggregated from various locations and time periods across the Philippines; and the Hanihara series capturing various local indigenous, ethnic groups that are together identified as Philippine Negrito. Parental craniometrics are selected from the Howells dataset and more recently collected samples from Europe and Asia. Using unsupervised clustering, we investigate the algorithmically defined three-cluster, or trihybrid admixture, model to infer continental ancestry for each individual, reporting their relative proportions of Asian, European, and African admixture. We employ similar clustering procedures to identify more complex models, with a larger number of clusters, to explore patterns of affinity between our four Philippine samples and the recently acquired samples from Vietnam, Thailand, China (Hong Kong), Japan, and Korea. These analyses give insight into the relationships between both macro and micro geographic regions, such that, at the country level, we reveal how different population dynamics – whether geo-political, -economic, -historical and/or -social – structure the ancestral makeup of Asian peoples, especially in the degree of European and African admixture. From these ancestry estimates, we find that population of origin explains 38-51% of the variation in each ancestry component and we detect significant differences among the Asian samples in their quantities of ancestry. Filipinos appear considerably admixed, as they appear to carry almost 20% less Asian ancestry than the average quantity (90%) estimated for the other Asian groups. We also reveal substructure within our representation of modern Filipinos, such that differences in the patterns of three-way admixture exist between each of the four Philippine samples, finding that the Manila cemetery sample has the highest level of Asian ancestry and, as we might expect, that the Negrito sample has the greatest quantity of African ancestry. We perform additional analyses that introduce craniometrics from the Howells Australo-Melanesian series in order to more fully investigate their relationship to the Asian samples and to better understand the African contributions common to the Philippine Negritos especially, as well as the other Southeast Asians and the Spanish and Portuguese groups. By mapping the cluster patterns on a global scale, these analyses reveal, with craniometrics just as with genetic loci, patterns of affinity that are informative of the complex history of Southeast Asia, as they are suggestive of the vestiges of migration, trade, and colonialism, as well as more recent periods of isolation, marginalization, and occupation

    Genetic structure of First Nation communities in the Pacific Northwest

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    This study presents genetic data for nine Native American populations from northern North America. Analyses of genetic variation focus on the Pacific Northwest (PNW). Using mitochondrial, Y chromosomal and autosomal DNA variants, we aim to more closely address the relationships of geography and language with present genetic diversity among the regional PNW Native American populations. Patterns of genetic diversity exhibited by the three genetic systems were consistent with our hypotheses, in that we expected genetic variation to be more strongly explained by geographic proximity than linguistic structure. Our findings were corroborated through a variety on analytic approaches, with the unrooted trees for the three genetic systems consistently separating inland from coastal PNW populations. Furthermore, the AMOVA tests support the trends exhibited by the unrooted trees, with geographic partitioning of PNW populations (FCT = 19.43%, p = 0.010 ± 0.009) accounting for over twice as much of the observed genetic variation compared with linguistic partitioning of the same populations (FCT = 9.15%, p = 0.193 ± 0.013). These findings demonstrate a consensus with previous PNW population studies examining the relationships of genome-wide variation, mitochondrial haplogroup frequencies, and skeletal morphology with geography and language

    Comparing Genetic Variation among Latin American Immigrants: Implications for Forensic Casework in the Arizona- and Texas-MĂ©xico Borderlands

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    The humanitarian crisis on the United States-MĂ©xico border is a long standing and evolving crisis in which nearly 8,000 deaths have been reported in the last two decades. These deaths are largely distributed across the Arizona-MĂ©xico and Texas-MĂ©xico border regions where demographic trends for immigrants attempting to cross into the U.S. have shifted dramatically. The demographic change and volume of immigrants seeking shelter in the U.S. presents new challenges for the forensic practitioners entrusted with the identification of individuals who lose their lives during the final segment of their journey. Within this Border context, the present study investigates how genetic variation inferred from forensically significant microsatellites can provide valuable information on regions of origin for unidentified remains on the group level. To explore how we can mobilize these genetic data to inform identification strategies, we conduct a comparative genetic analysis of identified and unidentified immigrant cases from the Arizona- and Texas-MĂ©xico contexts, as well as 27 other Latin American groups. Allele frequencies were utilized to calculate FST, and relationships were visually depicted in a multidimensional scaling plot. A Spearman correlation coefficient analysis assessed the strength and significance of population relationships and an agglomerative clustering analysis assessed population clusters. Results indicate that Arizona-MĂ©xico immigrants have the strongest relationship (\u3e80%) with groups from El Salvador, Guatemala, MĂ©xico, and an indigenous group from Southern MĂ©xico. Texas-MĂ©xico immigrants have the strongest relationships (\u3e80%) with groups from Belize, Colombia, Costa Rica, El Salvador, Guatemala, Honduras, and Nicaragua. These findings agree with, and are discussed in comparison to, previously reported demographic trends, population genetics research, and population history analyses. We emphasize the utility and necessity of coupling genetic variation research with a nuanced anthropological perspective for identification processes in the U.S-MĂ©xico border context

    Review of deuterium–tritium results from the Tokamak Fusion Test Reactor

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    A simulation for exploring the effects of the “trait list” method’s subjectivity on consistency and accuracy of ancestry estimations

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    The nonmetric “trait list” methodology is widely used for estimating ancestry of skeletal remains. However, the effects of the method’s embedded subjectivity on subsequent accuracy and consistency are largely unknown. We develop a mathematical simulation to test whether variation in the application of the “trait list” method alters the ancestry estimation for a given case. Our simulation explores how variations in (i) trait selection, (ii) number of traits employed, and (iii) ancestry choice thresholds affect the ancestry estimation of an unidentified skeleton. Using two temporally and geographically diverse samples, the simulation demonstrates that trait selection, trait quantity, threshold choices, and the exclusion of high-frequency traits had minimal effect on estimation of general ancestry. For all data sets and Runs, AccuracyAS was maintained above 90%. The authors close with a discussion on the logistical issues present when choosing traits, and how to avoid ancestry bias

    Human nose shape variation can be explained, in part, by local adaptation to temperature

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    Zaidi A.A., Mattern B.C., Claes P., Hughes C., ''Human nose shape variation can be explained, in part, by local adaptation to temperature'', American journal of physical anthropology, vol. 159, suppl. S62, pp. 343, March 2016 (85th annual meeting of the American Association of Physical Anthropologists (AAPA), April 12-16, 2016, Atlanta, GA, USA).status: publishe

    An Admixture Approach to Trihybrid Ancestry Variation in the Philippines with Implications for Forensic Anthropology

    Get PDF
    In this study, we investigated, for the first time from a forensic anthropological perspective, the question of mixed ancestry estimation for modern Filipinos with geographic origins in the Philippines. We derived estimates of continental ancestry using craniometrics from four sources: a new documented collection of current forensic significance from the Manila North Cemetery; the Howells cranial series representing a sample of unclaimed individuals from Manila but said largely to originate from more remote areas, with dates of death before 1940; the Hanihara sample aggregated from various locations and time periods across the Philippines; and the Hanihara series capturing various local indigenous, ethnic groups that are together identified as Philippine Negrito. Parental craniometrics were selected from the Howells data set and more recently collected samples from Europe and Asia. Using unsupervised clustering, we investigated the algorithmically defined three-cluster, or trihybrid admixture, model to infer continental ancestry for each individual, reporting their relative proportions of Asian, European, and African admixture. We used similar clustering procedures to identify more complex models, with a larger number of clusters, to explore patterns of affinity between our four Philippine samples and the recently acquired samples from Vietnam, Thailand, China (Hong Kong), Japan, and Korea. These analyses give insight into the relationships between both macro- and microgeographic regions, revealing at the country level how different population dynamics—whether political, economic, historical, and/or social—structure the ancestral makeup of Asian peoples, especially in the degree of European and African admixture. From these ancestry estimates, we found that population of origin explains 38–51% of the variation in each ancestry component, and we detected significant differences among the Asian samples in their quantities of ancestry. Filipinos appear considerably admixed, as they carry almost 20% less Asian ancestry than the average quantity (90%) estimated for the other Asian groups. We also revealed substructure within our representation of modern Filipinos, such that differences in the patterns of three-way admixture exist between each of the four Philippine samples; the Manila cemetery sample had the highest level of Asian ancestry, and, as we might expect, the Negrito sample had the greatest quantity of African ancestry. We performed additional analyses that introduced craniometrics from the Howells Australo-Melanesian series, to more fully investigate their relationship to the Asian samples and to better understand the African contributions common to the Philippine Negritos especially, as well as the other Southeast Asians and the Spanish and Portuguese groups. By mapping the cluster patterns on a global scale, these analyses reveal that, with craniometrics just as with genetic loci, patterns of affinity are informative of the complex history of Southeast Asia, as they suggest vestiges of migration, trade, and colonialism, as well as more recent periods of isolation, marginalization, and occupation
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