Cycloaddition Chemistry of a Silylene‐Nickel Complex toward Organic π‐Systems: From Reversibility to C−H Activation

The versatile cycloaddition chemistry of the Si−Ni multiple bond in the acyclic (amido)(chloro)silylene→Ni0 complex 1, [(TMSL)ClSi→Ni(NHC)2] (TMSL=N(SiMe3)Dipp; Dipp=2,6‐iPr2C6H4; NHC=C[(iPr)NC(Me)]2), toward unsaturated organic substrates is reported, which is both reminiscent of and expanding on the reactivity patterns of classical Fischer and Schrock carbene–metal complexes. Thus, 1:1 reaction of 1 with aldehydes, imines, alkynes, and even alkenes proceed to yield [2+2] cycloaddition products, leading to a range of four‐membered metallasilacycles. This cycloaddition is in fact reversible for ethylene, whereas addition of an excess of this olefin leads to quantitative sp2‐CH bond activation, via a 1‐nickela‐4‐silacyclohexane intermediate. These results have been supported by DFT calculations giving insights into key mechanistic aspects.DFG, 390540038, EXC 2008: UniSysCatTU Berlin, Open-Access-Mittel - 202

The c-terminal extension of a hybrid immunoglobulin A/G heavy chain is responsible for its Golgi-mediated sorting to the vacuole

We have assessed the ability of the plant secretory pathway to handle the expression of complex heterologous proteins by investigating the fate of a hybrid immunoglobulin A/G in tobacco cells. Although plant cells can express large amounts of the antibody, a relevant proportion is normally lost to vacuolar sorting and degradation. Here we show that the synthesis of high amounts of IgA/G does not impose stress on the plant secretory pathway. Plant cells can assemble antibody chains with high efficiency and vacuolar transport occurs only after the assembled immunoglobulins have traveled through the Golgi complex. We prove that vacuolar delivery of IgA/G depends on the presence of a cryptic sorting signal in the tailpiece of the IgA/G heavy chain. We also show that unassembled light chains are efficiently secreted as monomers by the plant secretory pathway

Neuromantic : from semi-manual to semi-automatic reconstruction of neuron morphology

The ability to create accurate geometric models of neuronal morphology is important for understanding the role of shape in information processing. Despite a significant amount of research on automating neuron reconstructions from image stacks obtained via microscopy, in practice most data are still collected manually. This paper describes Neuromantic, an open source system for three dimensional digital tracing of neurites. Neuromantic reconstructions are comparable in quality to those of existing commercial and freeware systems while balancing speed and accuracy of manual reconstruction. The combination of semi-automatic tracing, intuitive editing, and ability of visualizing large image stacks on standard computing platforms provides a versatile tool that can help address the reconstructions availability bottleneck. Practical considerations for reducing the computational time and space requirements of the extended algorithm are also discussed

To pay or not: game theoretic models of ransomware

Ransomware is a type of malware that encrypts files and demands a ransom from victims. It can be viewed as a form of kidnapping in which the criminal takes control of the victim’s files with the objective of financial gain. In this article, we review and develop the game theoretic literature on kidnapping in order to gain insight on ransomware. The prior literature on kidnapping has largely focused on political or terrorist hostage taking. We demonstrate, however, that key models within the literature can be adapted to give critical new insight on ransomware. We primarily focus on two models. The first gives insight on the optimal ransom that criminals should charge. The second gives insight on the role of deterrence through preventative measures. A key insight from both models will be the importance of spillover effects across victims. We will argue that such spillovers point to the need for some level of outside intervention, by governments or otherwise, to tackle ransomware

Exploring the Psychological Mechanisms used in Ransomware Splash Screens

The present study examined a selection of 76 ransomware splash screens collected from a variety of sources. These splash screens were analysed according to surface information, including aspects of visual appearance, the use of language, cultural icons, payment and payment types. The results from the current study showed that, whilst there was a wide variation in the construction of ransomware splash screens, there was a good degree of commonality, particularly in terms of the structure and use of key aspects of social engineering used to elicit payment from the victims. There was the emergence of a sub-set of ransomware that, in the context of this report, was termed ‘Cuckoo’ ransomware. This type of attack often purported to be from an official source requesting payment for alleged transgressions

Employees Attitudes towards Cyber Security and Risky Online Behaviours: An Empirical Assessment in the United Kingdom

The present study aimed to explore if the size of company an individual works for, age or attitudes towards cyber security affected frequency to engage in risky online behaviours. A total of 515 participants aged between 18-84 in full or part-time employment were asked to complete a questionnaire that consisted of two scales. One measured their attitude towards cyber security and general awareness of cyber crime, the other examined the types of ‘risky’ cyber security behaviours they were engaged in. The results demonstrated a significant negative correlation between attitudes towards cyber security and risky cyber security behaviours, with more negative attitudes being linked to higher levels of risky behaviours. There were also significant differences according to company size and age group according to frequency of engaging in risky cyber security behaviour and attitudes towards cyber security. The findings are presented as furthering our understanding of how employee attitudes contribute to company cyber security, as well as highlighting how the size of an organisation could be linked to difference in knowledge and adherence to ISA protocols

“I cannot live without my [tablet]”: children's experiences of using tablet technology within the home

The current study aimed to examine children’s experiences of using tablet technology within the home. Eighteen children aged between eight and nine years old took part in four separate focus group discussions. Thematic analysis revealed three predominant themes: a battle of boundaries, a tool to escape the surrounding world, and an emerging dependency on tablet technology. The data implies that there is a growing dependency on tablet technology use among this age group. The current study also outlines that many children engage in a variety of techniques to circumvent parental limits on their tablet usage. However, other children discussed a lack of clear rules and restrictions for their use of tablet devices. The findings suggest that covert and unregulated use of tablet technology may have a detrimental impact upon children, particularly in relation to reduced social interaction, fatigue and increased family tensions due to excessive usage. Further research of child interactions with a wide variety of digital technology and media is warranted. Such exploration would further our understanding of the potential advantages and disadvantages for such technology use, as well as presenting a pathway to produce more effective guidance on home use