The Digital Police Officer using linguistic analysis to identify cybercriminals

The aim of the Digital Police Officer project (DPO) is to identify cybercriminals based on their writing style. When a criminal underground forum is closed down, cybercriminals move to another one to further their illicit business. These users do not necessarily return with the same uername. We are producing a demo that can still identify such cybercriminals. We look at the way they communicate, analysing the characteristics of forum users (i.e. based on their vocabulary and grammar) to build a linguistic fingerprin

Formation of NH3 and N-2 from Atomic Nitrogen and Hydrogen on Rhodium(111)

Reactions of adsorbed N atoms on Rh(111) to N2 and NH3 were studied with temp. programmed desorption, temp. programmed reaction spectroscopy, and static secondary ion mass spectrometry. For N-atom coverages below ~0.15 monolayers, desorption of N2 follows simple second-order kinetics, but at higher coverages the desorption traces broaden to higher temps. Hydrogenation to NH3 can be described by a stepwise addn. of H atoms to Nads in which the reaction from NH2,ads+Hads to NH3,ads dets. the rate. The activation energy for the rate detg. step is 76 kJ/mol. The desorption of NH3 from Rb(111) was studied sep. The kinetic parameters for desorption at low NH3 coverage are 81 kJ/mol and 1013 s-1, but the rate of desorption increases rapidly with increasing NH3 coverage. It is argued that the remarkable coverage dependence of the desorption rate is unlikely to be caused by lateral repulsive interactions but may be due to a coverage of the pre-exponential facto

Cyanide intermediates in catalytic reduction of NO by C2H4 on Rhodium(III)

Temp.-programmed reaction spectroscopy and secondary ion mass spectrometry (SIMS) have been applied to study reactions of NO and C2H4 coadsorbed on Rh(111). As expected, H2O, CO2, and N2 are the main products at low C2H4 coverages, but at higher coverages H2, HCN, CO, and NO, and even some C2N2 evolve as well. Static SIMS indicates the formation of a large supply of adsorbed cyanide species, part of which desorbs as HCN, while the remainder decomps. and is responsible for delayed formation of N2. For the highest C2H4 coverages, the majority of the nitrogen atoms in the initially adsorbed NO desorbs as HC

Modeling of the reactivity of vibrationally excited molecules in a corona plasma for catalytic reactions

A model is developed to describe the transfer of vibrational energy from excited gas molecules to a heterogeneous surface or to heating of the gas. Diffusion of excited species is included in the model. The model is used to compute the maximum possible energy efficiency of a plasma-induced catalytic reaction, which is driven by vibrationally excited molecules. The computational results of the model are correlated to experimental data on quenching rates and the relevant parameters of the self-sustained discharge. It is con cluded that the mechanism of plasma-induced catalysis with vibrationally excited molecules is highly unlikely

You can't see what you can't see: Experimental evidence for how much relevant information may be missed due to Google's Web search personalisation

The influence of Web search personalisation on professional knowledge work is an understudied area. Here we investigate how public sector officials self-assess their dependency on the Google Web search engine, whether they are aware of the potential impact of algorithmic biases on their ability to retrieve all relevant information, and how much relevant information may actually be missed due to Web search personalisation. We find that the majority of participants in our experimental study are neither aware that there is a potential problem nor do they have a strategy to mitigate the risk of missing relevant information when performing online searches. Most significantly, we provide empirical evidence that up to 20% of relevant information may be missed due to Web search personalisation. This work has significant implications for Web research by public sector professionals, who should be provided with training about the potential algorithmic biases that may affect their judgments and decision making, as well as clear guidelines how to minimise the risk of missing relevant information.Comment: paper submitted to the 11th Intl. Conf. on Social Informatics; revision corrects error in interpretation of parameter Psi/p in RBO resulting from discrepancy between the documentation of the implementation in R (https://rdrr.io/bioc/gespeR/man/rbo.html) and the original definition (https://dl.acm.org/citation.cfm?id=1852106) as per 20/05/201

Photolytic and thermolytic decomposition products from iron pentacarbonyl adsorbed on Y zeolite

Zeolite supported iron systems obtained by photolysis and thermolysis of Fe(CO)5/Na---Y adducts are characterized via evaluation of the respective magnetic isotherms taken with a FONER magnetometer at T = 4.2 K. Thermolysis under fast heating in inert gas and under fluidized shallow bed conditions completes within a few minutes at not, vert, similar 500 K, and gives iron clusters of which at least 70 to 90 wt% is smaller than 1 nm. Prolonged photolysis at 290 K in the same fluidized bed conditions does not result in the formation of ‘naked’ iron(O) clusters, but gives a limited fraction of magnetically coupled Fex(CO)y entities. Photodimerization cannot be excluded to be the main reaction path

RhoA-ROCK signaling is involved in contraction-mediated inhibition of SERCA2a expression in cardiomyocytes

In neonatal ventricular cardiomyocytes (NVCM), decreased contractile activity stimulates sarco-endoplasmic reticulum Ca2+-ATPase2a (SERCA2a), analogous to reduced myocardial load in vivo. This study investigated in contracting NVCM the role of load-dependent RhoA-ROCK signaling in SERCA2a regulation. Contractile arrest of NVCM resulted in low peri-nuclear localized RhoA levels relative to contracting NVCM. In arrested NVCM, ROCK activity was decreased (59%) and paralleled a loss in F-actin levels. Y-27632-induced ROCK inhibition in contracting NVCM increased SERCA2a messenger RNA expression by 150%. This stimulation was transcriptional, as evident from transfections with the SERCA2a promoter. A reciprocal effect of Y-27632 treatment on the promoter activity of atrial natriuretic factor was observed. SERCA2a transcription was not altered by co-transfection of the RhoA-ROCK-dependent serum response factor (SRF) alone or in combination with myocardin. Furthermore, GATA4, another ROCK-dependent transcription factor, induced rather than repressed SERCA2a transcription. This study shows that contractile activity suppresses SERCA2a gene expression via RhoA-ROCK-dependent transcription modulation. This modulation is likely to be accomplished by a transcription factor other than SRF, myocardin, or GATA4

Disorder-specific cognitive profiles in major depressive disorder and generalized anxiety disorder

BACKGROUND: This investigation examines differences in cognitive profiles in subjects with major depressive disorder (MDD) and generalized anxiety disorder (GAD). METHODS: Data were used from subjects with current MDD (n = 655), GAD (n = 107) and comorbid MDD/GAD (n = 266) diagnosis from the Netherlands Study of Depression and Anxiety (NESDA). The Composite Interview Diagnostic Instrument was used to diagnose MDD and GAD. Cognitive profiles were measured using the Leiden Index of Depression Sensitivity, the Anxiety Sensitivity Index, and the Penn State Worry Questionnaire. RESULTS: Results showed that differences in cognitive profiles between single MDD and single GAD subjects were present: scores on hopelessness/suicidality and rumination were significantly higher in MDD than GAD, whereas anxiety sensitivity for physical concerns and pathological worry were higher in GAD than MDD. The cognitive profile of comorbid MDD/GAD showed more extreme depression cognitions compared to single disorders, and a similar anxiety profile compared to single GAD subjects. CONCLUSIONS: Despite the commonalities in cognitive profiles in MDD and GAD, there are differences suggesting that MDD and GAD have disorder-specific cognitive profiles. Findings of this investigation give support for models like the cognitive content-specificity model and the tripartite model and could provide useful handles for treatment focus