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51.
Erik Jeppesen Martin Appelt Kirsten Hastrup Bjarne Grønnow Anders Mosbech John P. Smol Thomas A. Davidson 《Ambio》2018,47(2):296-309
Based on lake sediment data, archaeological findings, and historical records, we describe rapid transformations, resilience and resistance in societies and ecosystems, and their interactions in the past in the North Water area related to changes in climate and historical events. Examples are the formation of the polynya itself and the early arrival of people, ca. 4500 years ago, and later major human immigrations (different societies, cultural encounters, or abandonment) from other regions in the Arctic. While the early immigrations had relatively modest and localised effect on the ecosystem, the later-incoming culture in the early thirteenth century was marked by extensive migrations into and out of the area and abrupt shifts in hunting technologies. This has had long-lasting consequences for the local lake ecosystems. Large natural transformations in the ecosystems have also occurred over relatively short time periods related to changes in the polynya. Finally, we discuss the future perspectives for the North Water area given the many threats, but also opportunities. 相似文献
52.
Social insects use complex chemical communication systems to govern many aspects of their life. We studied chemical changes in Dufours gland secretions associated with ovary development in several genotypes of honeybees. We found that C28–C38 esters were associated only with cavity nesting honeybee queens, while the alcohol eicosenol was associated only with their non-laying workers. In contrast, both egg-laying anarchistic workers and all parasitic Cape workers from queenright colonies showed the typical queen pattern (i.e. esters present and eicosenol absent), while egg-laying wild-type and anarchistic workers in queenless colonies showed an intermediate pattern, producing both esters and eicosenol but at intermediate levels. Furthermore, neither esters nor eicosenol were found in aerial nesting honeybee species. Both esters and eicosenol are biosynthetically similar compounds since both are recognizable products of fatty acid biosynthesis. Therefore, we propose that in honeybees the biosynthesis of esters and eicosenol in the Dufours gland is caste-regulated and this pathway has been conserved over evolutionary time. 相似文献
53.
54.
Frans J. Los MD PhD Diane Van Opstal Martin P. Schol Johannes L. J. Gaillard Helen Brandenburg Ans M. W. Van Den Ouweland Peter A. In 'T Veld 《黑龙江环境通报》1995,15(12):1155-1159
A prenatally detected case of a rare mosaic tetrasomy 12p/trisomy 12p is reported, presenting as the well-known accessory isochromosome 12p and a supernumerary single 12p marker in 17/24 and 6/24 clones of cultured amniotic fluid cells, respectively. The chromosomal nature of both marker chromosomes was investigated in cultured amniotic fluid cells by fluorescent in situ hybridization with various probes: the 12-centromeric probes pa12H8 and D12Z3, a whole chromosome 12 paint, and the chromosome 12p-specific paint M28. DNA analysis revealed a maternal origin of the extra 12p material. After counselling, the parents requested termination of pregnancy. Inspection and autopsy of the fetus revealed many of the dysmorphisms and internal structural abnormalities of the Pallister–Killian syndrome. 相似文献
55.
Power matters in closing the phenotyping gap 总被引:1,自引:0,他引:1
Meyer CW Elvert R Scherag A Ehrhardt N Gailus-Durner V Fuchs H Schäfer H Hrabé de Angelis M Heldmaier G Klingenspor M 《Die Naturwissenschaften》2007,94(5):401-406
Much of our understanding of physiology and metabolism is derived from investigating mouse mutants and transgenic mice, and
open-access platforms for standardized mouse phenotyping such as the German Mouse Clinic (GMC) are currently viewed as one
powerful tool for identifying novel gene-function relationships. Phenotyping or phenotypic screening involves the comparison of wild-type control mice with their mutant or transgenic littermates. In our study, we explored
the extent to which standardized phenotyping will succeed in detecting biologically relevant phenotypic differences in mice
generated and provided by different collaborators. We analyzed quantitative metabolic data (body mass, energy intake, and
energy metabolized) collected at the GMC under the current workflow, and used them for statistical power considerations. Our
results demonstrate that there is substantial variability in these parameters among lines of wild-type C57BL/6 (B6) mice from
different sources. Given this variable background noise in mice that serve as controls, subtle phenotypes in mutant or transgenic
littermates may be overlooked. Furthermore, a phenotype observed in one cohort of a mutant line may not be reproducible (to
the same extent) in mice coming from a different environment or supplier. In the light of these constraints, we encourage
researchers to incorporate information on intrastrain variability into future study planning, or to perform advanced hierarchical
analyses. Both will ultimately improve the detectability of novel phenotypes by phenotypic screening.
Carola W. Meyer and Ralf Elvert contributed equally to this work. 相似文献
56.
Ivonne Bedei Karl-Philipp Gloning Luc Joyeux Matthias Meyer-Wittkopf Daria Willner Martin Krapp Alexander Scharf Jan Degenhardt Kai-Sven Heling Peter Kozlowski Kathrin Trautmann Kai M. Jahns Annegret Geipel Ismail Tekesin Michael Elsässer Lucas Wilhelm Ingo Gottschalk Jan-Erik Baumüller Cahit Birdir Andreas Schröer Felix Zöllner Aline Wolter Johanna Schenk Tascha Gehrke Alicia Spaeth Roland Axt-Fliedner 《黑龙江环境通报》2023,43(2):183-191
Objective
Omphalocele is known to be associated with genetic anomalies like trisomy 13, 18 and Beckwith–Wiedemann syndrome, but not with Turner syndrome (TS). Our aim was to assess the incidence of omphalocele in fetuses with TS, the phenotype of this association with other anomalies, their karyotype, and the fetal outcomes.Method
Retrospective multicenter study of fetuses with confirmed diagnosis of TS. Data were extracted from a detailed questionnaire sent to specialists in prenatal ultrasound.Results
680 fetuses with TS were included in this analysis. Incidence of small omphalocele in fetuses diagnosed ≥12 weeks was 3.1%. Including fetuses diagnosed before 12 weeks, it was 5.1%. 97.1% (34/35) of the affected fetuses had one or more associated anomalies including increased nuchal translucency (≥3 mm) and/or cystic hygroma (94.3%), hydrops/skin edema (71.1%), and cardiac anomalies (40%). The karyotype was 45,X in all fetuses. Fetal outcomes were poor with only 1 fetus born alive.Conclusion
TS with 45,X karyotype but not with X chromosome variants is associated with small omphalocele. Most of these fetuses have associated anomalies and a poor prognosis. Our data suggest an association of TS with omphalocele, which is evident from the first trimester. 相似文献57.
Jennifer Kidd Elizabeth Patberg Meghan McGath Berrin Monteleone Martin Chavez 《黑龙江环境通报》2023,43(9):1251-1254
A 26 year old nulligravida presented at 24 weeks gestation for the second opinion of abnormal fetal profile and mid-face views on ultrasound at another institution. A detailed fetal anatomic ultrasound at our facility revealed the absence of fetal lens and globes bilaterally consistent with bilateral anophthalmia (HP: 0000528) without other anomalies. Karyotype and chromosomal microarray analysis were completed from amniocentesis sample. After these results, duo exome testing with paternal sequencing was completed from proband amniotic fluid sample and parental blood samples. A pathogenic variant in SOX2 (NM_003106.3: c.513C>G p.(Tyr171*Ter)) with heterozygous autosomal dominant inheritance resulted. On duo exome testing with paternal segregation analysis, the variant was found to be consistent with likely sporadic de novo inheritance. The SOX2 variant reported is consistent with the fetal phenotype in this case. While germline mosaicism could exist, this identified variant provided the family with a likely explanation for this proband's finding. This ultrasound and genetic testing allowed the family to make decisions related to planning in current and future pregnancies. 相似文献
58.
59.
Anders Malmendal Jesper Givskov Sørensen Johannes Overgaard Martin Holmstrup Niels Chr. Nielsen Volker Loeschcke 《Die Naturwissenschaften》2013,100(5):417-427
We investigated the global metabolite response to artificial selection for tolerance to stressful conditions such as cold, heat, starvation, and desiccation, and for longevity in Drosophila melanogaster. Our findings were compared to data from other levels of biological organization, including gene expression, physiological traits, and organismal stress tolerance phenotype. Overall, we found that selection for environmental stress tolerance changes the metabolomic 1H NMR fingerprint largely in a similar manner independent of the trait selected for, indicating that experimental evolution led to a general stress selection response at the metabolomic level. Integrative analyses across data sets showed little similarity when general correlations between selection effects at the level of the metabolome and gene expression were compared. This is likely due to the fact that the changes caused by these selection regimes were rather mild and/or that the dominating determinants for gene expression and metabolite levels were different. However, expression of a number of genes was correlated with the metabolite data. Many of the identified genes were general stress response genes that are down-regulated in response to selection for some of the stresses in this study. Overall, the results illustrate that selection markedly alters the metabolite profile and that the coupling between different levels of biological organization indeed is present though not very strong for stress selection at this level. The results highlight the extreme complexity of environmental stress adaptation and the difficulty of extrapolating and interpreting responses across levels of biological organization. 相似文献
60.
Nicholas Tatrallyay Martin Stadelmann 《Mitigation and Adaptation Strategies for Global Change》2013,18(7):903-919
This study analyzes the effectiveness and efficiency of the two principal United Nations (UN) climate change mitigation finance mechanisms, the Clean Development Mechanism (CDM) and the Global Environment Facility (GEF). The realised abatement and costs of the two mechanisms in India and Brazil (using data from 28 GEF and 233 CDM project documents) are compared with theoretical marginal abatement cost curves, based on bottom-up technology studies. We find that both mechanisms have focused on negative and low-cost abatement potential but still leave substantial theoretical potential in this cost range untapped. CDM has more effectively harvested abatement potential of industrial gases and methane emissions, whereas GEF has more successfully targeted demand-side energy efficiency (EE) and transport emission reduction opportunities. CDM has excelled at capturing abatement potential in areas with a limited understanding of abatement, highlighting the shortcomings of theoretical estimates (such as Marginal Abatement Cost Curves) and the benefits of a market mechanism. In some sectors and technologies (particularly renewable energy), the two mechanisms overlapped, which suggests a need for better coordination in the future. 相似文献