3,183,878 research outputs found
Countering the Australian 'ndrangheta: The criminalisation of mafia behaviour in Australia between national and comparative criminal law
Mafia-type criminal groups belonging to, or originated from, the Calabrian ‘ndrangheta from Southern Italy, have been object of recent academic research and media attention in Australia. The Australian ‘ndrangheta, as qualified form of organised crime, poses new challenges for law enforcement in the country. This paper briefly looks at the strategies to fight organised crime in Australia, with specific focus on anti-association laws. By using a comparative approach, the paper will look at the criminalisation of mafias as qualified forms of organised crime in other two jurisdictions, Italy and the USA, to advocate for an effective mafia criminalisation in Australia. In conclusion, this paper will argue that, in order to also fight mafia phenomena, criminal law in Australia should focus on behaviours of organised crime groups rather than only on the criminalisation of proscribed associations and their illegal activities
DNA-coated Functional Oil Droplets
Many industrial soft materials often include oil-in-water (O/W) emulsions at
the core of their formulations. By using tuneable interface stabilizing agents,
such emulsions can self-assemble into complex structures. DNA has been used for
decades as a thermoresponsive highly specific binding agent between hard and,
recently, soft colloids. Up until now, emulsion droplets functionalized with
DNA had relatively low coating densities and were expensive to scale up. Here a
general O/W DNA-coating method using functional non-ionic amphiphilic block
copolymers, both diblock and triblock, is presented. The hydrophilic
polyethylene glycol ends of the surfactants are functionalized with azides,
allowing for efficient, dense and controlled coupling of dibenzocyclooctane
functionalized DNA to the polymers through a strain-promoted alkyne-azide click
reaction. The protocol is readily scalable due to the triblock's commercial
availability. Different production methods (ultrasonication, microfluidics and
membrane emulsification) are used with different oils (hexadecane and silicone
oil) to produce functional droplets in various size ranges (sub-micron, and ), showcasing the generality of
the protocol. Thermoreversible sub-micron emulsion gels, hierarchical
"raspberry" droplets and controlled droplet release from a flat DNA-coated
surface are demonstrated. The emulsion stability and polydispersity is
evaluated using dynamic light scattering and optical microscopy. The generality
and simplicity of the method opens up new applications in soft matter and
biotechnological research and industrial advances.Comment: 7 pages, 2 figures, 1 tabl
Atomic force microscopy shows that vaccinia topoisomerase IB generates filaments on DNA in a cooperative fashion
Type IB DNA topoisomerases cleave and rejoin one strand of the DNA duplex, allowing for the removal of supercoils generated during replication and transcription. In addition, electron microscopy of cellular and viral TopIB–DNA complexes has suggested that the enzyme promotes long-range DNA–DNA crossovers and synapses. Here, we have used the atomic force microscope to visualize and quantify the interaction between vaccinia topoisomerase IB (vTopIB) and DNA. vTopIB was found to form filaments on nicked-circular DNA by intramolecular synapsis of two segments of a single DNA molecule. Measuring the filament length as a function of protein concentration showed that synapsis is a highly cooperative process. At high protein:DNA ratios, synapses between distinct DNA molecules were observed, which led to the formation of large vTopIB-induced DNA clusters. These clusters were observed in the presence of Mg(2+), Ca(2+) or Mn(2+), suggesting that the formation of intermolecular vTopIB-mediated DNA synapsis is favored by screening of the DNA charge
Mitochondrial Dna Replacement Versus Nuclear Dna Persistence
In this paper we consider two populations whose generations are not
overlapping and whose size is large. The number of males and females in both
populations is constant. Any generation is replaced by a new one and any
individual has two parents for what concerns nuclear DNA and a single one (the
mother) for what concerns mtDNA. Moreover, at any generation some individuals
migrate from the first population to the second.
In a finite random time , the mtDNA of the second population is completely
replaced by the mtDNA of the first. In the same time, the nuclear DNA is not
completely replaced and a fraction of the ancient nuclear DNA persists. We
compute both and . Since this study shows that complete replacement of
mtDNA in a population is compatible with the persistence of a large fraction of
nuclear DNA, it may have some relevance for the Out of Africa/Multiregional
debate in Paleoanthropology
From Nonspecific DNA–Protein Encounter Complexes to the Prediction of DNA–Protein Interactions
©2009 Gao, Skolnick. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.doi:10.1371/journal.pcbi.1000341DNA–protein interactions are involved in many essential biological activities. Because there is no simple mapping code between DNA base pairs and protein amino acids, the prediction of DNA–protein interactions is a challenging problem. Here, we present a novel computational approach for predicting DNA-binding protein residues and DNA–protein interaction modes without knowing its specific DNA target sequence. Given the structure of a DNA-binding protein, the method first generates an ensemble of complex structures obtained by rigid-body docking with a nonspecific canonical B-DNA. Representative models are subsequently selected through clustering and ranking by their DNA–protein interfacial energy. Analysis of these encounter complex models suggests that the recognition sites for specific DNA binding are usually favorable interaction sites for the nonspecific DNA probe and that nonspecific DNA–protein interaction modes exhibit some similarity to specific DNA–protein binding modes. Although the method requires as input the knowledge that the protein binds DNA, in benchmark tests, it achieves better performance in identifying DNA-binding sites than three previously established methods, which are based on sophisticated machine-learning techniques. We further apply our method to protein structures predicted through modeling and demonstrate that our method performs satisfactorily on protein models whose root-mean-square Ca deviation from native is up to 5 Å from their native structures. This study provides valuable structural insights into how a specific DNA-binding protein interacts with a nonspecific DNA sequence. The similarity between the specific DNA–protein interaction mode and nonspecific interaction modes may reflect an important sampling step in search of its specific DNA targets by a DNA-binding protein
The DNA damage response acts as a safeguardagainst harmful DNA–RNA hybrids ofdifferent origins
Despite playing physiological roles in specific situations, DNA–RNA hybrids threat genome integrity. To investigate how cells do counteract spontaneous DNA–RNA hybrids, here we screen an siRNA library covering 240 human DNA damage response (DDR) genes and select siRNAs causing DNA–RNA hybrid accumulation and a significant increase in hybrid‐dependent DNA breakage. We identify post‐replicative repair and DNA damage checkpoint factors, including those of the ATM/CHK2 and ATR/CHK1 pathways. Thus, spontaneous DNA–RNA hybrids are likely a major source of replication stress, but they can also accumulate and menace genome integrity as a consequence of unrepaired DSBs and post‐replicative ssDNA gaps in normal cells. We show that DNA–RNA hybrid accumulation correlates with increased DNA damage and chromatin compaction marks. Our results suggest that different mechanisms can lead to DNA–RNA hybrids with distinct consequences for replication and DNA dynamics at each cell cycle stage and support the conclusion that DNA–RNA hybrids are a common source of spontaneous DNA damage that remains unsolved under a deficient DDR.European Research Council (ERC2014AdG669898TARLOOP)Worldwide Cancer Research (WCR15-00098
Disorder in DNA-Linked Gold Nanoparticle Assemblies
We report experimental observations on the effect of disorder on the phase
behavior of DNA-linked nanoparticle assemblies. Variation in DNA linker lengths
results in different melting temperatures of the DNA-linked nanoparticle
assemblies. We observed an unusual trend of a non-monotonic ``zigzag'' pattern
in the melting temperature as a function of DNAlinker length. Linker DNA
resulting in unequal DNA duplex lengths introduces disorder and lowers the
melting temperature of the nanoparticle system. Comparison with free DNA
thermodynamics shows that such an anomalous zigzag pattern does not exist for
free DNA duplex melting, which suggests that the disorder introduced by unequal
DNA duplex lengths results in this unusual collective behavior of DNA-linked
nanoparticle assemblies.Comment: 4 pages, 4 figures, Phys.Rev.Lett. (2005), to appea
Mechanisms of Zika virus infection and neuropathogenesis
A spotlight has been focused on the mosquito-borne Zika virus (ZIKV) because of its epidemic outbreak in Brazil and Latin America, as well as the severe neurological manifestations of microcephaly and Guillain–Barré syndrome associated with infection. In this review, we discuss the recent literature on ZIKV-host interactions, including new mechanistic insight concerning the basis of ZIKV-induced neuropathogenesis
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