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We examined the effect of mimicry on how 16-month-old infants learn by observation a novel tool use action, which consisted of using a rake to retrieve a toy. Across four conditions, we manipulated whether during an initial play phase, an adult mimicked the infant''s play or not (testing the effect of mimicry), the infant played with the adult or played alone (controlling the effect of interacting with a contingent partner) and whether the infant saw a demonstration of the tool''s use or not (evaluating baseline performance). We found that infants who had been mimicked learned best from a demonstration of the rake''s use and performed better than infants who only played with the experimenter without mimicry or played by themselves before the demonstration. As expected, infants did not learn from a demonstration of the rake''s use when they played by themselves and thus had no previous interaction with an experimenter. The mechanisms driving this powerful learning effect of mimicry are discussed. 相似文献
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Tracing the genetic origin of Europe's first farmers reveals insights into their social organization
Anna Szécsényi-Nagy Guido Brandt Wolfgang Haak Victoria Keerl János Jakucs Sabine M?ller-Rieker Kitti K?hler Balázs Gusztáv Mende Krisztián Oross Tibor Marton Anett Osztás Viktória Kiss Marc Fecher Gy?rgy Pálfi Erika Molnár Katalin Seb?k András Czene Tibor Paluch Mario ?laus Mario Novak Nives Pe?ina-?laus Brigitta ?sz Vanda Voicsek Krisztina Somogyi Gábor Tóth Bernd Kromer Eszter Bánffy Kurt W. Alt 《Proceedings. Biological sciences / The Royal Society》2015,282(1805)
Farming was established in Central Europe by the Linearbandkeramik culture (LBK), a well-investigated archaeological horizon, which emerged in the Carpathian Basin, in today''s Hungary. However, the genetic background of the LBK genesis is yet unclear. Here we present 9 Y chromosomal and 84 mitochondrial DNA profiles from Mesolithic, Neolithic Starčevo and LBK sites (seventh/sixth millennia BC) from the Carpathian Basin and southeastern Europe. We detect genetic continuity of both maternal and paternal elements during the initial spread of agriculture, and confirm the substantial genetic impact of early southeastern European and Carpathian Basin farming cultures on Central European populations of the sixth–fourth millennia BC. Comprehensive Y chromosomal and mitochondrial DNA population genetic analyses demonstrate a clear affinity of the early farmers to the modern Near East and Caucasus, tracing the expansion from that region through southeastern Europe and the Carpathian Basin into Central Europe. However, our results also reveal contrasting patterns for male and female genetic diversity in the European Neolithic, suggesting a system of patrilineal descent and patrilocal residential rules among the early farmers. 相似文献
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JG Hansen W Gao J Dupuis GT O’Connor W Tang M Kowgier A Sood SA Gharib LJ Palmer M Fornage SR Heckbert BM Psaty SL Booth SUNLIGHT Consortium Patricia A Cassano 《Respiratory research》2015,16(1)
Background
Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults.Methods
We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV1) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV1 in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV1 in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts.Results
We found a positive cross-sectional association between 25(OH)D and FEV1 in FHS Offspring and Third Generation participants (P = 0.004). There was little or no association between 25(OH)D and longitudinal change in FEV1 in Third Generation participants (P = 0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV1 (gene-based P < 0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV1 in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P = 0.09).Conclusions
Serum 25(OH)D status was associated with cross-sectional FEV1, but not longitudinal change in FEV1. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV1 and is a promising candidate gene for further studies.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0238-y) contains supplementary material, which is available to authorized users. 相似文献7.
Patterns of metal distribution in hypersaline microbialites during early diagenesis: Implications for the fossil record 下载免费PDF全文
M. C. Sforna M. Daye P. Philippot A. Somogyi M. A. van Zuilen K. Medjoubi E. Gérard F. Jamme C. Dupraz O. Braissant C. Glunk P. T. Visscher 《Geobiology》2017,15(2):259-279
The use of metals as biosignatures in the fossil stromatolite record requires understanding of the processes controlling the initial metal(loid) incorporation and diagenetic preservation in living microbialites. Here, we report the distribution of metals and the organic fraction within the lithifying microbialite of the hypersaline Big Pond Lake (Bahamas). Using synchrotron‐based X‐ray microfluorescence, confocal, and biphoton microscopies at different scales (cm–μm) in combination with traditional geochemical analyses, we show that the initial cation sorption at the surface of an active microbialite is governed by passive binding to the organic matrix, resulting in a homogeneous metal distribution. During early diagenesis, the metabolic activity in deeper microbialite layers slows down and the distribution of the metals becomes progressively heterogeneous, resulting from remobilization and concentration as metal(loid)‐enriched sulfides, which are aligned with the lamination of the microbialite. In addition, we were able to identify globules containing significant Mn, Cu, Zn, and As enrichments potentially produced through microbial activity. The similarity of the metal(loid) distributions observed in the Big Pond microbialite to those observed in the Archean stromatolites of Tumbiana provides the foundation for a conceptual model of the evolution of the metal distribution through initial growth, early diagenesis, and fossilization of a microbialite, with a potential application to the fossil record. 相似文献
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Picoeukaryotes dominate the phytoplankton of Lake Balaton—the largest shallow lake in Central Europe—in the winter period.
We examined the annual dynamics of picoplankton abundance and composition in the lake in order to establish if the picoeukaryotes
merely survive the harsher winter conditions or they are able to grow in the ice-covered lake when the entire phytoplankton
is limited by low light and temperature. Lake Balaton has an annual temperature range of 1–29°C, and it is usually frozen
between December and February for 30–60 days. In the spring-autumn period phycocyanin and phycoerythrin rich Cyanobacteria
are the dominant picoplankters, and picoeukaryotes are negligible. Our five-year study shows the presence of three types of
picophytoplankton assemblages in Lake Balaton: (1) Phycoerythrin-rich Cyanobacteria—the dominant summer picoplankters in the
mesotrophic lake area; (2) Phycocyanin-rich Cyanobacteria—the most abundant summer picoplankters in the eutrophic lake area
and; (3) Picoeukaryotes—the dominant winter picoplankters in the whole lake. The observed winter abundance of picoeukaryotes
was high (up to 3 × 105 cells ml−1), their highest biomass (520 μg l−1) exceeded the maximum summer biomass of picocyanobacteria (500 μg l−1). Our results indicate that the winter predominance of picoeukaryotes is a regular phenomenon in Lake Balaton, irrespective
of the absence or presence of the ice cover. Picoeukaryotes are able to grow at as low as 1–2°C water temperature, while the
total phytoplankton biomass show the lowest annual values in the winter period. In agreement with earlier findings, the contribution
of picocyanobacteria to the total phytoplankton biomass in Lake Balaton is inversely related to the total phytoplankton biomass,
whereas no such relationship was observable in the case of picoeukaryotes. 相似文献
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John R. de Almeida Gordon H. Guyatt Sachin Sud Joanne Dorion Michael D. Hill Michael R. Kolber Jane Lea Sylvia Loong Reg Balvinder K. Somogyi Brian D. Westerberg Chris White Joseph M. Chen Bell Palsy Working Group Canadian Society of Otolaryngology – Head Neck Surgery Canadian Neurological Sciences Federation 《CMAJ》2014,186(12):917-922
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Vesela Yancheva Elenka Georgieva Stela Stoyanova Iliana Velcheva Dóra Somogyi Krisztián Nyeste László Antal 《Acta zoologica》2020,101(4):431-446
The present study aimed to investigate for the first time the health status of the Caucasian dwarf goby Knipowitschia caucasica (Berg, 1916, Fishes of freshwaters of Russian Empire, p. 563, Moscow, Russia: Dep. Zemledeliya) (Teleostei: Gobiidae) from an anthropogenically loaded site in Hungary using histopathological analyses on multiple tissues. For that purpose, fish were collected from the public beach at Tiszafüred near the River Tisza. Gills, liver and kidney were subjected to histopathological analyses, and the results showed different alterations in each organ, which also differed in their extent and severity. In addition, we also found lesions in the reproductive organs of both, male and female fish which, overall, we hypothesized could be due to untreated municipal wastewaters, most likely contaminated with endocrine-disrupting chemicals. The multi-organ histopathological analyses of Caucasian dwarf gobies revealed different lesions, prevalence and severity in each target organ, as follows: liver>gills>kidney>gonad (testes and ovaries). These histopathological lesions can be assessed as good indicators of contamination by endocrine-disrupting chemicals of freshwater ecosystems. 相似文献