10 research outputs found
Cation-Dependent Fluorescent Properties of Naphthalimide Derivatives with N-Benzocrown Ether Fragment
The investigation of N-phenyl-4-amino- and N-phenyl 4-acetamido-1,8-naphthalimides containing N-benzo- 15-crown-5 ether substituent showed that the presence of ionophoric fragment as N-substituent in naphthalimide molecule provides the design of compound possessing the properties of fluorescent receptor. The addition of metal cations does not change the position of absorption and emission bands but substantial increases the fluorescence intensity. The study of molecules included the theoretical and experimental (optical, NMR) methods, analysis of intramolecular charge (electron) transfer and fluorescence properties in the presence and absence of metal ions
Synthesis and spectral properties of 4-amino- and 4-acetylamino-N-arylnaphthalimides containing electron-donating groups in the N-aryl substituent
A method for the synthesis of N-aryl-substituted 4 amino- and 4-acetylaminonaphthalimide derivatives with mono- and dialkoxy groups or a 15-crow-5 moiety in the N-aryl substituent is described. The introduction of electron-donating alkoxy groups into the benzene ring of the N-aryl fragment results in fluorescence quenching of the naphthalimide chromophore, which is most pronounced in the spectra of N-acetyl derivatives. The photophysical properties of the synthesized 4-amino- and 4-acetylaminonaphthalimides depend on the solvent polarity and its specific solvating ability due to H-bonding. The crown containing compounds are promising fluorescent chemosensors for metal cations
Consequences of past climate change and recent human persecution on mitogenomic diversity in the arctic fox
Ancient DNA provides a powerful means to investigate the timing, rate and extent of population declines caused by extrinsic factors, such as past climate change and human activities. One species probably affected by both these factors is the arctic fox, which had a large distribution during the last glaciation that subsequently contracted at the start of the Holocene. More recently, the arctic fox population in Scandinavia went through a demographic bottleneck owing to human persecution. To investigate the consequences of these processes, we generated mitogenome sequences from a temporal dataset comprising Pleistocene, historical and modern arctic fox samples. We found no evidence that Pleistocene populations in mid-latitude Europe or Russia contributed to the present-day gene pool of the Scandinavian population, suggesting that postglacial climate warming led to local population extinctions. Furthermore, during the twentieth-century bottleneck in Scandinavia, at least half of the mitogenome haplotypes were lost, consistent with a 20-fold reduction in female effective population size. In conclusion, these results suggest that the arctic fox in mainland Western Europe has lost genetic diversity as a result of both past climate change and human persecution. Consequently, it might be particularly vulnerable to the future Challenges posed by climate change. This article is part of a discussion meeting issue ‘The past is a Foreign country: how much can the fossil record actually inform conservation?’publishedVersio
CroSSED sequence, a new tool for 3D processing in geosciences using the free software 3DSlicer
The research by JD was funded through a European Union's Horizon 2020 research and innovation programme under the Marie Skodowska-Curie grant agreement No 792314 (ICON-SE). The research of FJR-T was funded by projects CGL2015-66835-P and PID2019-104625RB-100 (Secretaria de Estado de Investigacion, Desarrollo e Innovacion, Spain), B-RNM-072-UGR18 (FEDER Andalucia), P18-RT-4074 (Junta de Andalucia), and Scientific Excellence Unit UCE-2016-05 (Universidad de Granada). The research was conducted within the "The Drifters Research Group" (RHUL) and the "Ichnology and Palaeoenvironment Research Group" (UGR). We thank Russell Garwood and one Anonymous Reviewer for their valuable comments on the manuscript and David Nesbitt and Jean Sanders for editing the English.The scientific application of 3D imaging has evolved significantly over recent years. These techniques make it possible to study internal features by non-destructive analysis. Despite its potential, the development of 3D imaging in the Geosciences is behind other fields due to the high cost of commercial software and the scarce free alternatives. Most free software was designed for the Health Sciences, and the pre-settled workflows are not suited to geoscientific materials. Thus, an outstanding challenge in the Geosciences is to define workflows using free alternatives for Computed Tomography (CT) data processing, promoting data sharing, reproducibility, and the development of specific extensions. We present CroSSED, a processing sequence for 3D reconstructions of CT data, using 3DSlicer, a popular application in medical imaging. Its usefulness is exemplified in the study of burrows that have low-density contrast with respect to the host sediment. For geoscientists who have access to CT data and wish to reconstruct 3D structures, this method offers a wide range of possibilities and contributes to open-science and applied CT studies.European Union's Horizon 2020 research and innovation programme under the Marie Skodowska-Curie grant
792314Secretaria de Estado de Investigacion, Desarrollo e Innovacion, Spain
CGL2015-66835-P
PID2019-104625RB-100FEDER Andalucia
B-RNM-072-UGR18Junta de Andalucia
P18-RT-4074Universidad de Granada UCE-2016-0
Consequences of past climate change and recent human persecution on mitogenomic diversity in the arctic fox
Ancient DNA provides a powerful means to investigate the timing, rate and extent of population declines caused by extrinsic factors, such as past climate change and human activities. One species probably affected by both these factors is the arctic fox, which had a large distribution during the last glaciation that subsequently contracted at the start of the Holocene. More recently, the arctic fox population in Scandinavia went through a demographic bottleneck owing to human persecution. To investigate the consequences of these processes, we generated mitogenome sequences from a temporal dataset comprising Pleistocene, historical and modern arctic fox samples. We found no evidence that Pleistocene populations in mid-latitude Europe or Russia contributed to the present-day gene pool of the Scandinavian population, suggesting that postglacial climate warming led to local population extinctions. Furthermore, during the twentieth-century bottleneck in Scandinavia, at least half of the mitogenome haplotypes were lost, consistent with a 20-fold reduction in female effective population size. In conclusion, these results suggest that the arctic fox in mainland Western Europe has lost genetic diversity as a result of both past climate change and human persecution. Consequently, it might be particularly vulnerable to the future Challenges posed by climate change. This article is part of a discussion meeting issue ‘The past is a Foreign country: how much can the fossil record actually inform conservation?’publishedVersio