The influence of parathyroid hormone upon bone formation in xenopus laevis

KI

Towards a cyberterrorism life-cycle (CLC) model

Cyberterrorism has emerged as a new threat in the Information and Communication Technology (ICT) landscape. The ease of use, affordability, remote capabilities and access to critical targets makes cyberterrorism a potential threat to cause wide-scale damage. Cyberterrorism is often incorrectly perceived as encompassing all cybercrimes. However, cyberterrorism differs from cybercrime in various ways including motivation, attack goals, techniques and effects. Motivations for cyberterrorism, which is similar to terrorism in general, stem from religious, social and political views. Cyberterrorists generally would seek to have high impact in order to gain publicity for their cause, whereas cybercriminals often prefer to have their acts undetected in order to hide their financial theft, fraud or espionage. Therefore, there are various factors that drive the development of a cyberterrorist. This paper proposes a model for the development of cyberterrorism in order to show the various influential forces. The Cyberterrorism Life-Cycle (CLC) model presented in this paper is composed of five phases: Prepare, Acquaint, Choose, Execute, and Deter (PACED). In addition the paper looks at various factors, including social, practices, objectives, targets and countermeasures, which are mapped onto the PACED phases in order to show the interaction and dynamic nature during the life-cycle development

Mentalizing the body: spatial and social cognition in anosognosia for hemiplegia

Following right-hemisphere damage, a specific disorder of motor awareness can occur called anosognosia for hemiplegia, i.e. the denial of motor deficits contralateral to a brain lesion. The study of anosognosia can offer unique insights into the neurocognitive basis of awareness. Typically, however, awareness is assessed as a first person judgement and the ability of patients to think about their bodies in more ‘objective’ (third person) terms is not directly assessed. This may be important as right-hemisphere spatial abilities may underlie our ability to take third person perspectives. This possibility was assessed for the first time in the present study. We investigated third person perspective taking using both visuospatial and verbal tasks in right-hemisphere stroke patients with anosognosia ( n = 15) and without anosognosia ( n = 15), as well as neurologically healthy control subjects ( n = 15). The anosognosic group performed worse than both control groups when having to perform the tasks from a third versus a first person perspective. Individual analysis further revealed a classical dissociation between most anosognosic patients and control subjects in mental (but not visuospatial) third person perspective taking abilities. Finally, the severity of unawareness in anosognosia patients was correlated to greater impairments in such third person, mental perspective taking abilities (but not visuospatial perspective taking). In voxel-based lesion mapping we also identified the lesion sites linked with such deficits, including some brain areas previously associated with inhibition, perspective taking and mentalizing, such as the inferior and middle frontal gyri, as well as the supramarginal and superior temporal gyri. These results suggest that neurocognitive deficits in mental perspective taking may contribute to anosognosia and provide novel insights regarding the relation between self-awareness and social cognition

Predicting enhanced absorption of light gases in polyethylene using simplified PC-SAFT and SAFT-VR

International audienceAbsorption of light gases in polyethylene (PE) is studied using two versions of the Statistical Associating Fluid Theory (SAFT): SAFT for chain molecules with attractive potentials of variable range (VR) and simplified perturbed-chain (PC) SAFT. Emphasis is placed on the light gases typically present during ethylene polymerisation in the gas-phase reactor (GPR) process. The two approaches are validated using experimental binary-mixture data for gas absorbed in PE, and predictions are made for mixtures of more components. For most cases studied both SAFT versions perform equally well. For the case of ternary mixtures of two gases with PE, it is predicted that the less-volatile of the two gases acts to enhance the absorption of the more-volatile gas, while the more-volatile gas inhibits the absorption of the less-volatile gas. This general behaviour is also predicted in mixtures containing more gases, such as typical reactor mixtures. The magnitude of the effect may vary considerably, depending on the relative proximity of the gas-mixture saturation pressure to the reactor pressure; for example it is predicted that the absorption of ethylene may be approximately doubled if diluent gases, propane or nitrogen, are partially or completely replaced by less-volatile butane or pentane for a reactor pressure similar to 2 MPa. In the case of a co-polymerisation reaction, it is predicted that increases in absorption of both co-monomers may be obtained in roughly equal proportion. Our findings cast light on the so-called co-monomer effect, in which substantial increases in the rate of ethylene polymerisation are observed in the presence of hexene co-monomer, while suggesting that the effect is more general and not restricted to co-monomer. For example, similar rate increases may be expected in the presence of, e.g., pentane instead of hexene, but without the change in the branch structure of the produced polymer that is inevitable when the amount of co-monomer is increased

Clathrate equilibrium data for CO 2 +N 2 mixtures with TBAB, TBAF, CP, TBAB+CP, TBAF+CP promoters

International audienceCarbon Dioxide capture and sequestration (CCS) is nowadays an important area of research for alleviating CO 2 emissions worldwide. According to [1], CO 2 is globally the largest pollutant to which the global warming is attributed. Consequently, hydrates can become of great importance as they form the basis for a new technology that concerns CO 2 capture from flue gases (hydrate crystallization). In this work hydrate equilibrium data measured at the Centre Thermodynamic of Processes in MINES ParisTech (France) are presented as part of a collaborative project funded by the Danish Technical Research Council. More particularly, in this study experimental results for hydrate dissociation with several promoters are presented. The isochoric method is used to determine the gas hydrate dissociation points. Different CO 2 +N 2 gas mixtures were used with presence of promoters such as tetra-butylammonium bromide (TBAB), tetra-butylammonium fluoride (TBAF), cyclopentane (CP) and mixtures of TBAB and TBAF with CP. The combination of TBA halides with CP was inspired by [2] as it came out synergetic effect that enhances promotion between TBAB (5% w/w) and CP (5% v/v). The results have shown synergetic effect for 20% w/w TBAB+CP (5% v/v) and partly (>30 bar) for 5% w/w TBAF+CP (5% v/v). Concerning experiments with pure promoter, there is excellent consistency between our results and literature for different gas mixtures and promoter concentrations. Moreover, they exhibit very good agreement with existing literature

Reviewing National Cybersecurity Awareness in Africa: An Empirical Study

Over the last years, there has been an unprecedented increase in cybercrime globally. Africa is a region with one of the highest rates of cybercrime and significant financial losses. Yet, awareness of risks in cyberspace amongst citizens of African countries is in its infancy and capacity building initiatives focusing on designing and implementing such campaigns are lacking. As part of the Global Cybersecurity Capacity Centre (GCSCC) programme, we visited six countries and assessed their cybersecurity posture based on the Cybersecurity Capacity Maturity Model for Nations (CMM) developed by the GCSCC. In this paper, we analyse qualitative data collected by conducting focus groups with experts in awareness campaigns during our visits. We reflect on best practice approaches for developing campaigns and draw conclusions on what the current state of African countries is regarding awareness in risks from cybercrime, what are the main obstacles in combating cybercrime and how countries should identify and prioritise their actions. We believe that our paper contributes in research concerned with how to mitigate cybercrime