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Diverse protection systems for improving security: a study with AntiVirus engines
Diverse “barriers” or “protection systems” are very common in many industries, especially in safety-critical ones where the designers must use “defense in depth” techniques to prevent safety failures. Similar techniques are also commonly prescribed for security systems: using multiple, diverse detection systems to prevent security breaches. However empirical evidence of the effectiveness of diversity is rare. We present results of an empirical study which uses a large-scale dataset to assess the benefits of diversity with an important category of security systems: AntiVirus products. The analysis was based on 1599 malware samples collected from a distributed honeypot deployment over a period of 178 days. The malware samples were sent to the signature engines of 32 different AntiVirus products hosted by the VirusTotal service. We also present an exploratory model which shows that the number of diverse protection layers that are needed to achieve “perfect” detection with our dataset follows an exponential power-law distribution. If this distribution is shown to be generic with other datasets, it would be a cost-effective means for predicting the probability of perfect detection for systems that use a large number of barriers based on measurements made with systems that are composed of fewer (say 2, 3) barriers
Physical origin of the power-law tailed statistical distributions
Starting from the BBGKY hierarchy, describing the kinetics of nonlinear
particle system, we obtain the relevant entropy and stationary distribution
function. Subsequently, by employing the Lorentz transformations we propose the
relativistic generalization of the exponential and logarithmic functions. The
related particle distribution and entropy represents the relativistic extension
of the classical Maxwell-Boltzmann distribution and of the Boltzmann entropy
respectively and define the statistical mechanics presented in [Phys. Rev. E
{\bf 66}, 056125 (2002)] and [Phys. Rev. E {\bf 72}, 036108 (2005). The
achievements of the present effort, support the idea that the experimentally
observed power law tailed statistical distributions in plasma physics, are
enforced by the relativistic microscopic particle dynamics.Comment: 6 pages. arXiv admin note: substantial text overlap with
arXiv:1110.3944, arXiv:1012.390
Dysfunctional telomeres in primary cells from Fanconi anemia FANCD2 patients
© 2012 Joksic et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.This article has been made available through the Brunel Open Access Publishing Fund.Background: Fanconi anemia (FA) is characterized by sensitivity to DNA cross-linking agents, mild cellular, and marked clinical radio sensitivity. In this study we investigated telomeric abnormalities of non-immortalized primary cells (lymphocytes and fibroblasts) derived from FA patients of the FA-D2 complementation group, which provides a more accurate physiological assessment than is possible with transformed cells or animal models. Results: We analyzed telomere length, telomere dysfunction-induced foci (TIFs), sister chromatid exchanges (SCE), telomere sister chromatid exchanges (T-SCE), apoptosis and expression of shelterin components TRF1 and TRF2. FANCD2 lymphocytes exhibited multiple types of telomeric abnormalities, including premature telomere shortening, increase in telomeric recombination and aberrant telomeric structures ranging from fragile to long-string extended telomeres. The baseline incidence of SCE in FANCD2 lymphocytes was reduced when compared to control, but in response to diepoxybutane (DEB) the 2-fold higher rate of SCE was observed. In contrast, control lymphocytes showed decreased SCE incidence in response to DEB treatment. FANCD2 fibroblasts revealed a high percentage of TIFs, decreased expression of TRF1 and invariable expression of TRF2. The percentage of TIFs inversely correlated with telomere length, emphasizing that telomere shortening is the major reason for the loss of telomere capping function. Upon irradiation, a significant decrease of TIFs was observed at all recovery times. Surprisingly, a considerable percentage of TIF positive cells disappeared at the same time when incidence of γ-H2AX foci was maximal. Both FANCD2 leucocytes and fibroblasts appeared to die spontaneously at higher rate than control. This trend was more evident upon irradiation; the percentage of leucocytes underwent apoptosis was 2.59- fold higher than that in control, while fibroblasts exhibited a 2- h delay before entering apoptosis. Conclusion:
The results of our study showed that primary cells originating from FA-D2 patients display shorten telomeres, elevated incidence of T-SCEs and high frequency of TIFs. Disappearance of TIFs in early response to irradiation represent distinctive feature of FANCD2 cells that should be examined further.This article is made available through the Brunel Open Access Publishing Fund. This work was supported by the Ministry of Education and Science of the Republic of Serbia (Project No.173046)
Making GDPR Usable: A Model to Support Usability Evaluations of Privacy
We introduce a new model for evaluating privacy that builds on the criteria
proposed by the EuroPriSe certification scheme by adding usability criteria.
Our model is visually represented through a cube, called Usable Privacy Cube
(or UP Cube), where each of its three axes of variability captures,
respectively: rights of the data subjects, privacy principles, and usable
privacy criteria. We slightly reorganize the criteria of EuroPriSe to fit with
the UP Cube model, i.e., we show how EuroPriSe can be viewed as a combination
of only rights and principles, forming the two axes at the basis of our UP
Cube. In this way we also want to bring out two perspectives on privacy: that
of the data subjects and, respectively, that of the controllers/processors. We
define usable privacy criteria based on usability goals that we have extracted
from the whole text of the General Data Protection Regulation. The criteria are
designed to produce measurements of the level of usability with which the goals
are reached. Precisely, we measure effectiveness, efficiency, and satisfaction,
considering both the objective and the perceived usability outcomes, producing
measures of accuracy and completeness, of resource utilization (e.g., time,
effort, financial), and measures resulting from satisfaction scales. In the
long run, the UP Cube is meant to be the model behind a new certification
methodology capable of evaluating the usability of privacy, to the benefit of
common users. For industries, considering also the usability of privacy would
allow for greater business differentiation, beyond GDPR compliance.Comment: 41 pages, 2 figures, 1 table, and appendixe
PLANiTS: a curated sequence reference dataset for plant ITS DNA metabarcoding
DNA metabarcoding combines DNA barcoding with high-throughput sequencing to identify different taxa within environmental communities. The ITS has already been proposed and widely used as universal barcode marker for plants, but a comprehensive, updated and accurate reference dataset of plant ITS sequences has not been available so far. Here, we constructed reference datasets of Viridiplantae ITS1, ITS2 and entire ITS sequences including both Chlorophyta and Streptophyta. The sequences were retrieved from NCBI, and the ITS region was extracted. The sequences underwent identity check to remove misidentified records and were clustered at 99% identity to reduce redundancy and computational effort. For this step, we developed a script called 'better clustering for QIIME' (bc4q) to ensure that the representative sequences are chosen according to the composition of the cluster at a different taxonomic level. The three datasets obtained with the bc4q script are PLANiTS1 (100\u2009224 sequences), PLANiTS2 (96\u2009771 sequences) and PLANiTS (97\u2009550 sequences), and all are pre-formatted for QIIME, being this the most used bioinformatic pipeline for metabarcoding analysis. Being curated and updated reference databases, PLANiTS1, PLANiTS2 and PLANiTS are proposed as a reliable, pivotal first step for a general standardization of plant DNA metabarcoding studies. The bc4q script is presented as a new tool useful in each research dealing with sequences clustering. Database URL: https://github.com/apallavicini/bc4q; https://github.com/apallavicini/PLANiTS
Environmental DNA assessment of airborne plant and fungal seasonal diversity
Environmental DNA (eDNA) metabarcoding and metagenomics analyses can improve taxonomic resolution in biodiversity studies. Only recently, these techniques have been applied in aerobiology, to target bacteria, fungi and plants in airborne samples. Here, we present a nine-month aerobiological study applying eDNA metabarcoding in which we analyzed simultaneously airborne diversity and variation of fungi and plants across five locations in North and Central Italy. We correlated species composition with the ecological characteristics of the sites and the seasons. The most abundant taxa among all sites and seasons were the fungal genera Cladosporium, Alternaria, and Epicoccum and the plant genera Brassica, Corylus, Cupressus and Linum, the latter being much more variable among sites. PERMANOVA and indicator species analyses showed that the plant diversity from air samples is significantly correlated with seasons, while that of fungi varied according to the interaction between seasons and sites. The results consolidate the performance of a new eDNA metabarcoding pipeline for the simultaneous amplification and analysis of airborne plant and fungal particles. They also highlight the promising complementarity of this approach with more traditional biomonitoring frameworks and routine reports of air quality provided by environmental agencies
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