1,152 research outputs found

    zeek-osquery: Host-Network Correlation for Advanced Monitoring and Intrusion Detection

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    Intrusion Detection Systems (IDSs) can analyze network traffic for signs of attacks and intrusions. However, encrypted communication limits their visibility and sophisticated attackers additionally try to evade their detection. To overcome these limitations, we extend the scope of Network IDSs (NIDSs) with additional data from the hosts. For that, we propose the integrated open-source zeek-osquery platform that combines the Zeek IDS with the osquery host monitor. Our platform can collect, process, and correlate host and network data at large scale, e.g., to attribute network flows to processes and users. The platform can be flexibly extended with own detection scripts using already correlated, but also additional and dynamically retrieved host data. A distributed deployment enables it to scale with an arbitrary number of osquery hosts. Our evaluation results indicate that a single Zeek instance can manage more than 870 osquery hosts and can attribute more than 96% of TCP connections to host-side applications and users in real-time.Comment: Accepted for publication at ICT Systems Security and Privacy Protection (IFIP) SEC 202

    Physical Exercise Training versus Relaxation in Allogeneic stem cell transplantation (PETRA Study) – Rationale and design of a randomized trial to evaluate a yearlong exercise intervention on overall survival and side-effects after allogeneic stem cell transplantation

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    Background: Allogeneic stem cell transplantation (allo-HCT) is associated with high treatment-related mortality and innumerable physical and psychosocial complications and side-effects, such as high fatigue levels, loss of physical performance, infections, graft-versus-host disease (GvHD) and distress. This leads to a reduced quality of life, not only during and after transplantation, but also in the long term. Exercise interventions have been shown to be beneficial in allo-HCT patients. However, to date, no study has focused on long-term effects and survival. Previous exercise studies used ‘usual care’ control groups, leaving it unclear to what extent the observed effects are based on the physical effects of exercise itself, or rather on psychosocial factors such as personal attention. Furthermore, effects of exercise on and severity of GvHD have not been examined so far. We therefore aim to investigate the effects and biological mechanisms of exercise on side-effects, complications and survival in allo-HCT patients during and after transplantation. Methods/design: The PETRA study is a randomized, controlled intervention trial investigating the effects of a yearlong partly supervised mixed exercise intervention (endurance and resistance exercises, 3–5 times per week) in 256 patients during and after allogeneic stem cell transplantation. Patients in the control group perform progressive muscle relaxation training (Jacobsen method) with the same frequency. Main inclusion criterion is planned allo-HCT. Main exclusion criteria are increased fracture risk, no walking capability or severe cardiorespiratory problems. Primary endpoint is overall survival after two years; secondary endpoints are non-relapse mortality, median survival, patient reported outcomes including cancer related fatigue and quality of life, physical performance, body composition, haematological/immunological reconstitution, inflammatory parameters, severity of complications and side-effects (e.g. GvHD and infections), and cognitive capacity. Discussion: The PETRA study will contribute to a better understanding of the physiological and psychological effects of exercise training and their biological mechanisms in cancer patients after allo-HCT. The ultimate goal is the implementation of optimized intervention programs to reduce side-effects and improve quality of life and potentially prognosis after allogeneic stem cell transplantation. Trial registration: ClinicalTrials.gov Identifier: NCT0137439

    Microseismic joint location and anisotropic velocity inversion for hydraulic fracturing in a tight Bakken reservoir

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    To improve the accuracy of microseismic event locations, we developed a new inversion method with double-difference constraints for determining the hypocenters and the anisotropic velocity model for unconventional reservoirs. We applied this method to a microseismic data set monitoring a Middle Bakken completion in the Beaver Lodge area of North Dakota. Geophone arrays in four observation wells improved the ray coverage for the velocity inversion. Using an accurate anisotropic velocity model is important to correctly assess the height growth of the hydraulically induced fractures in the Middle Bakken. Our results showed that (1) moderate-to-strong anisotropy exists in all studied sedimentary layers, especially in the Upper and Lower Bakken shale formations, where the Thomsen parameters (ϵ and γ) can be greater than 0.4, (2) all the events selected for high signal-to-noise ratio and used for the joint velocity inversion are located in the Bakken and overlying Lodgepole formations, i.e., no events are detected in the Three Forks formation below the Bakken, and (3) more than half of the strong events are in two clusters at approximately 100 and 150 m above the Middle Bakken. Reoccurrence of strong, closely clustered events suggested activation of natural fractures or faults in the Lodgepole formation. The sensitivity analysis for the inversion results showed that the relative uncertainty in parameter δ is larger than other anisotropy parameters. The microseismic event locations and the anisotropic velocity model are validated by comparing synthetic and observed seismic waveforms and by S-wave splitting.Shell Oil Compan

    Stochastic ϕ4\phi^4-Theory in the Strong Coupling Limit

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    The stochastic ϕ4\phi^4-theory in dd-dimensions dynamically develops domain wall structures within which the order parameter is not continuous. We develop a statistical theory for the ϕ4\phi^4-theory driven with a random forcing which is white in time and Gaussian-correlated in space. A master equation is derived for the probability density function (PDF) of the order parameter, when the forcing correlation length is much smaller than the system size, but much larger than the typical width of the domain walls. Moreover, exact expressions for the one-point PDF and all the moments are given. We then investigate the intermittency issue in the strong coupling limit, and derive the tail of the PDF of the increments ϕ(x2)ϕ(x1)\phi(x_2) - \phi(x_1). The scaling laws for the structure functions of the increments are obtained through numerical simulations. It is shown that the moments of field increments defined by, Cb=C_b=, behave as x1x2ξb|x_1-x_2|^{\xi_b}, where ξb=b\xi_b=b for b1b\leq 1, and ξb=1\xi_b=1 for b1b\geq1Comment: 22 pages, 6 figures. to appear in Nuclear. Phys.

    Successful reduction of intraventricular asynchrony is associated with superior response to cardiac resynchronization therapy

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    <p>Abstract</p> <p>Background</p> <p>Cardiac resynchronization therapy (CRT) is generally associated with a low to moderate increase of the left ventricular ejection fraction (LVEF). In some patients, however, LVEF improves remarkably and reaches near-normal values. The aim of the present study was to further characterize these so called 'super-responders' with a special focus on the extent of intra- and interventricular asynchrony before and after device implantation compared to average responders.</p> <p>Methods</p> <p>37 consecutive patients who underwent CRT device implantation according to current guidelines were included in the study. Patients were examined by echocardiography before, one day after and six months after device implantation. Pre-defined criterion for superior response to CRT was an LVEF increase > 15% after six months.</p> <p>Results</p> <p>At follow-up, eight patients (21.6%) were identified as super-responders. There were no significant differences regarding age, gender, prevalence of ischemic heart disease and LVEF between average and super-responders at baseline. After six months, LVEF had significantly increased from 26.7% ± 5.7% to 33.1% ± 7.9% (<it>p </it>< 0.001) in average and from 24.0% ± 6.7% to 50.3% ± 7.4% (<it>p </it>< 0.001) in super-responders. Both groups showed a significant reduction of QRS duration as well as LV end-diastolic and -systolic volumes under CRT. At baseline, the interventricular mechanical delay (IVMD) was 53.7 ± 20.9 ms in average and 56.9 ± 22.4 ms in super-responders - representing a similar extent of interventricular asynchrony in both groups (<it>p </it>= 0.713). CRT significantly reduced the IVMD to 20.3 ± 15.7 (<it>p </it>< 0.001) in average and to 19.8 ± 15.9 ms (<it>p </it>= 0.013) in super-responders with no difference between both groups (<it>p </it>= 0.858). As a marker for intraventricular asynchrony, we assessed the longest intraventricular delay between six basal LV segments. At baseline, there was no difference between average (86.2 ± 30.5 ms) and super-responders (78.8 ± 23.6 ms, <it>p </it>= 0.528). CRT significantly reduced the longest intraventricular delay in both groups - with a significant difference between average (66.2 ± 36.2 ms) and super-responders (32.5 ± 18.3 ms, <it>p </it>= 0.022). Multivariate logistic regression analysis identified the longest intraventricular delay one day after device implantation as an independent predictor of superior response to CRT (<it>p </it>= 0.038).</p> <p>Conclusions</p> <p>A significant reduction of the longest intraventricular delay correlates with superior response to CRT.</p

    Darkness’s Descent on the American Anthropological Association: A Cautionary Tale

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    In September 2000, the self-styled “anthropological journalist” Patrick Tierney began to make public his work claiming that the Yanomamö people of South America had been actively—indeed brutally—harmed by the sociobiological anthropologist Napoleon Chagnon and the geneticist-physician James Neel. Following a florid summary of Tierney’s claims by the anthropologists Terence Turner and Leslie Sponsel, the American Anthropological Association (AAA) saw fit to take Tierney’s claims seriously by conducting a major investigation into the matter. This paper focuses on the AAA’s problematic actions in this case but also provides previously unpublished information on Tierney’s falsehoods. The work presented is based on a year of research by a historian of medicine and science. The author intends the work to function as a cautionary tale to scholarly associations, which have the challenging duty of protecting scholarship and scholars from baseless and sensationalistic charges in the era of the Internet and twenty-four-hour news cycles

    Wnt4 and LAP2alpha as pacemakers of Thymic Epithelial Senescence

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    Age-associated thymic involution has considerable physiological impact by inhibiting de novo T-cell selection. This impaired T-cell production leads to weakened immune responses. Yet the molecular mechanisms of thymic stromal adipose involution are not clear. Age-related alterations also occur in the murine thymus providing an excellent model system. In the present work structural and molecular changes of the murine thymic stroma were investigated during aging. We show that thymic epithelial senescence correlates with significant destruction of epithelial network followed by adipose involution. We also show in purified thymic epithelial cells the age-related down-regulation of Wnt4 (and subsequently FoxN1), and the prominent increase in LAP2α expression. These senescence-related changes of gene expression are strikingly similar to those observed during mesenchymal to pre-adipocyte differentiation of fibroblast cells suggesting similar molecular background in epithelial cells. For molecular level proof-of-principle stable LAP2α and Wnt4-over-expressing thymic epithelial cell lines were established. LAP2α over-expression provoked a surge of PPARγ expression, a transcription factor expressed in pre-adipocytes. In contrast, additional Wnt4 decreased the mRNA level of ADRP, a target gene of PPARγ. Murine embryonic thymic lobes have also been transfected with LAP2α- or Wnt4-encoding lentiviral vectors. As expected LAP2α over-expression increased, while additional Wnt4 secretion suppressed PPARγ expression. Based on these pioneer experiments we propose that decreased Wnt activity and increased LAP2α expression provide the molecular basis during thymic senescence. We suggest that these molecular changes trigger thymic epithelial senescence accompanied by adipose involution. This process may either occur directly where epithelium can trans-differentiate into pre-adipocytes; or indirectly where first epithelial to mesenchymal transition (EMT) occurs followed by subsequent pre-adipocyte differentiation. The latter version fits better with literature data and is supported by the observed histological and molecular level changes

    He Puts Out His Hand. You Put Out Your Hand. Emerging, Urban, Aboriginal Theatre-Makers. What Does it Take to Emerge?

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    The largest percentage of Aboriginal and Torres Strait Islanders in Australia live in Sydney. Despite this large Aboriginal and Torres Strait Islander population, there is there is very little recorded evidence of a prominent artistic presence of Aboriginal theatre-makers who are creating new, contemporary expressions of urban culture. From 2007-2011, PACT centre for emerging artists (PACT) created a series of Aboriginal-specific opportunities and programs for emerging, urban, Aboriginal theatre-makers who were interested in experimenting in new methods of creation and exploring their urban, lived experience. These opportunities generated a small, critical mass of Aboriginal theatre-makers. The program was in many aspects successful, however it also faced various challenges and misunderstandings. When one of the participating artists, Björn Stewart, presented a new performance work that expressed confusion, dislike and a sense of manipulation in the opportunities he was being offered as an artist by various organisations, it highlighted that perhaps the opportunities being offered to these theatre-makers were not what was perceived as being needed, and that there are varying motivations, agendas and expectations behind such opportunities by those providing them. This study identifies three key stakeholders who contribute to different points of the development of opportunities and new Aboriginal works: the funding body, the arts organisation and the artists. Using PACT’s Aboriginal-specific opportunities as a case study, this research set out to discover: (i) if current opportunities being offered to urban, emerging, Aboriginal theatre-makers are effective; (ii) what are the stakeholders’ perceptions about what is required; and most importantly, (iii) do these perceptions align with each other, and if not, what is the impact on Sydney, urban, emerging Aboriginal theatre-makers? To date, there has been no record of emerging, urban, theatre-makers having been consulted or given the opportunity to voice what they believe an emerging, urban, Aboriginal theatre-maker requires to “emerge”. This study begins that record
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