Comparison of System Call Representations for Intrusion Detection

Over the years, artificial neural networks have been applied successfully in many areas including IT security. Yet, neural networks can only process continuous input data. This is particularly challenging for security-related non-continuous data like system calls. This work focuses on four different options to preprocess sequences of system calls so that they can be processed by neural networks. These input options are based on one-hot encoding and learning word2vec or GloVe representations of system calls. As an additional option, we analyze if the mapping of system calls to their respective kernel modules is an adequate generalization step for (a) replacing system calls or (b) enhancing system call data with additional information regarding their context. However, when performing such preprocessing steps it is important to ensure that no relevant information is lost during the process. The overall objective of system call based intrusion detection is to categorize sequences of system calls as benign or malicious behavior. Therefore, this scenario is used to evaluate the different input options as a classification task. The results show, that each of the four different methods is a valid option when preprocessing input data, but the use of kernel modules only is not recommended because too much information is being lost during the mapping process.Comment: 12 pages, 1 figure, submitted to CISIS 201

Importance of Magnetic Resonance Imaging With Diffusion-weighted Imaging in Guiding Biopsy of Nodular Ganglioneuroblastoma: A Case Report

BACKGROUND: Nodular ganglioneuroblastoma is a rare peripheral neuroblastic tumor of variable prognosis. Accurate diagnosis, staging, and risk categorization can be particularly challenging in patients with nodular ganglioneuroblastoma due to the inherent heterogeneity of these lesions. CASE PRESENTATION: We illustrate the use of diffusion-weighted magnetic resonance imaging to identify tumor nodules and guide tumor biopsy in an almost 5-year-old boy with a large abdominal tumor. CONCLUSIONS: Diffusion-weighted magnetic resonance imaging was successful in detecting and guiding biopsy of a poorly differentiated neuroblastoma nodule within the context of a well-differentiated ganglioneuroma, allowing the diagnosis and characterization of a ganglioneuroblastoma nodular, thus influencing the child's prognosis and treatment

Normative Alethic Pluralism

Some philosophers have argued that truth is a norm of judgement and have provided a variety of formulations of this general thesis. In this paper, I shall side with these philosophers and assume that truth is a norm of judgement. What I am primarily interested in here are two core questions concerning the judgement-truth norm: (i) what are the normative relationships between truth and judgement? And (ii) do these relationships vary or are they constant? I argue for a pluralist picture—what I call Normative Alethic Pluralism (NAP)—according to which (i) there is more than one correct judgement-truth norm and (ii) the normative relationships between truth and judgement vary in relation to the subject matter of the judgement. By means of a comparative analysis of disagreement in three areas of the evaluative domain—refined aesthetics, basic taste and morality—I show that there is an important variability in the normative significance of disagreement—I call this the variability conjecture. By presenting a variation of Lynch’s scope problem for alethic monism, I argue that a monistic approach to the normative function of truth is unable to vindicate the conjecture. I then argue that normative alethic pluralism provides us with a promising model to account for it

Airway microbiome in adult survivors of extremely preterm birth: the EPICure study

Bronchopulmonary Dysplasia(BPD) is a major complication of preterm birth that leads to lifelong respiratory morbidity. The EPICure study has investigated the longitudinal health outcomes of infants born extremely preterm (<26 weeks-gestation). Our aim was to characterise the airway microbiome in young adults born extremely preterm (EP), with and without neonatal BPD, in comparison to matched term-born controls.Induced sputum was collected from 92 young adults age 19 years (51 EP and 41 controls). Typical respiratory pathogens were detected using quantitative-PCR. 16S-rRNA gene sequencing was completed on 74 samples (29 EP with BPD, 9 EP without BPD and 36 controls).The preterm group with BPD had the least diverse bacterial communities. The relative-abundance of Bacteriodetes, particularly Prevotella melaninogenica was significantly lower in the preterm group compared to controls. This decline was balanced by a nonsignificant increase in Firmicutes. Total Prevotella relative-abundance correlated with FEV1 z-score (ρ=0.272; p<0.05). Typical respiratory pathogens loads and prevalence were similar between groups.In conclusion, extremely preterm birth is associated with a significant dysbiosis in airway microbiome in young adulthood regardless of neonatal BPD status. This is characterised by a shift in the community composition away from Bacteriodetes as manifested in a significant drop in Prevotella relative-abundance

Conserved active site cysteine residue of archaeal THI4 homolog is essential for thiamine biosynthesis in Haloferax volcanii

Background: Thiamine (vitamin B1) is synthesized de novo by certain yeast, fungi, plants, protozoans, bacteria and archaea. The pathway of thiamine biosynthesis by archaea is poorly understood, particularly the route of sulfur relay to form the thiazole ring. Archaea harbor structural homologs of both the bacterial (ThiS-ThiF) and eukaryotic (THI4) proteins that mobilize sulfur to thiazole ring precursors by distinct mechanisms. Results: Based on comparative genome analysis, halophilic archaea are predicted to synthesize the pyrimidine moiety of thiamine by the bacterial pathway, initially suggesting that also a bacterial ThiS-ThiF type mechanism for synthesis of the thiazole ring is used in which the sulfur carrier ThiS is first activated by ThiF-catalyzed adenylation. The only ThiF homolog of Haloferax volcanii (UbaA) was deleted but this had no effect on growth in the absence of thiamine. Usage of the eukaryotic THI4-type sulfur relay was initially considered less likely for thiamine biosynthesis in archaea, since the active-site cysteine residue of yeast THI4p that donates the sulfur to the thiazole ring by a suicide mechanism is replaced by a histidine residue in many archaeal THI4 homologs and these are described as D-ribose-1,5-bisphosphate isomerases. The THI4 homolog of the halophilic archaea, including Hfx. volcanii (HVO_0665, HvThi4) was found to differ from that of methanogens and thermococci by having a cysteine residue (Cys165) corresponding to the conserved active site cysteine of yeast THI4p (Cys205). Deletion of HVO_0665 generated a thiamine auxotroph that was trans-complemented by a wild-type copy of HVO_0665, but not the modified gene encoding an HvThi4 C165A variant. Conclusions: Based on our results, we conclude that the archaeon Hfx. volcanii uses a yeast THI4-type mechanism for sulfur relay to form the thiazole ring of thiamine. We extend this finding to a relatively large group of archaea, including haloarchaea, ammonium oxidizing archaea, and some methanogen and Pyrococcus species, by observing that these organisms code for THI4 homologs that have a conserved active site cysteine residue which is likely used in thiamine biosynthesis. Thus, archaeal members of IPR002922 THI4 family that have a conserved cysteine active site should be reexamined for a function in thiamine biosynthesis

Response of carbon fluxes to water relations in a savanna ecosystem in South Africa

International audienceThe principal mechanisms that connect carbon fluxes with water relations in savanna ecosystems were studied by using eddy covariance in a savanna ecosystem at Kruger National Park, South Africa. Since the annual drought and rewetting cycle is a major factor influencing the function of savanna ecosystems, this work focused on the close inter-connection between water relations and carbon fluxes. Data from a nine-month measuring campaign lasting from the early wet season to the late dry season were used. Total ecosystem respiration showed highest values at the onset of the growing season, a slightly lower plateau during the main part of the growing season and a continuous decrease during the transition towards the dry season. The regulation of canopy conductance was changed in two ways: changes due to phenology during the course of the growing season and short-term acclimation to soil water conditions. The most constant parameter was water use efficiency that was influenced by VPD during the day but the VPD response curve of water usage did change only slightly during the course of the growing season and decreased by about 30% during the transition from wet to dry season. The regulation of canopy conductance and photosynthetic capacity were closely related. This observation meets recent leaf-level findings that stomatal closure triggers down-regulation of Rubisco during drought. Our results may show the effects of these processes on the ecosystem scale

A simple and robust method for connecting small-molecule drugs using gene-expression signatures

Interaction of a drug or chemical with a biological system can result in a gene-expression profile or signature characteristic of the event. Using a suitably robust algorithm these signatures can potentially be used to connect molecules with similar pharmacological or toxicological properties. The Connectivity Map was a novel concept and innovative tool first introduced by Lamb et al to connect small molecules, genes, and diseases using genomic signatures [Lamb et al (2006), Science 313, 1929-1935]. However, the Connectivity Map had some limitations, particularly there was no effective safeguard against false connections if the observed connections were considered on an individual-by-individual basis. Further when several connections to the same small-molecule compound were viewed as a set, the implicit null hypothesis tested was not the most relevant one for the discovery of real connections. Here we propose a simple and robust method for constructing the reference gene-expression profiles and a new connection scoring scheme, which importantly allows the valuation of statistical significance of all the connections observed. We tested the new method with the two example gene-signatures (HDAC inhibitors and Estrogens) used by Lamb et al and also a new gene signature of immunosuppressive drugs. Our testing with this new method shows that it achieves a higher level of specificity and sensitivity than the original method. For example, our method successfully identified raloxifene and tamoxifen as having significant anti-estrogen effects, while Lamb et al's Connectivity Map failed to identify these. With these properties our new method has potential use in drug development for the recognition of pharmacological and toxicological properties in new drug candidates.Comment: 8 pages, 2 figures, and 2 tables; supplementary data supplied as a ZIP fil

Impact of supplemental home enteral feeding postesophagectomy on nutrition, body composition, quality of life, and patient satisfaction

The aim of this prospective cohort study is to analyze the impact of supplemental home enteral nutrition (HEN) post-esophageal cancer surgery on nutritional parameters, quality of life (QL), and patient satisfaction. A systematic review reported that over 60% of patients lose \u3e10% of both body weight and BMI by 6 months after esophagectomy. Enteral feeding (EF) is increasingly a modern standard postoperatively; however, the impact of extended HEN postdischarge has not been systematically studied. One hundred forty-nine consecutive patients [mean age 62 ± 9, 80% male,76% adenocarcinoma, 66% on multimodal protocols, and 69% with BMI ≥ 25 kg/m2] were studied. Jejunal EF commenced day 1 postoperatively, and supplemental overnight HEN (764 kcal; 32g protein) continued on discharge for a planned further 4 weeks. Weight, BMI, and body composition analysis (bioimpedance analysis) were measured at baseline, preoperatively and at 1, 3, and 6 months, along with the EORTC QLQ-C30/OES18 QL measures. A patient satisfaction questionnaire addressed eight key items in relation to HEN (max score 100/item). Median (range) total duration of EF was 49 days (28-96). Overall compliance was 96%. At 6 months, compared with preoperatively, 58 (39%) patients lost \u3e10% weight, with median (IQR) loss of 6.8 (4-9) kg, and 62 (41%) patients lost \u3e10% BMI. Lean body mass and body fat were significantly (p \u3c 0.001) decreased. Mean global QL decreased (p \u3c 0.01) from 82 to 72. A high mean satisfaction score (\u3e70 ± 11/100) was reported, \u3e80 for practical training, activities of daily living, pain, anxiety, recovery and impact on caregivers, with lower scores for appetite (33 ± 24) and sleep (63 ± 30). Supplemental HEN for a minimum of one month postdischarge is associated with high compliance and patient satisfaction. Weight and BMI loss may still be substantial, however this may be less than published literature, in addition the impact on HR-QL may be attenuated. HEN has both subjective and objective rationale and merits further validation toward optimizing nutritional recovery and overall wellbeing

A Role for Dorsal and Ventral Hippocampus in Inter-Temporal Choice Cost-Benefit Decision Making

Previous studies suggest a preferential role for dorsal hippocampus (dHPC) in spatial memory tasks, whereas ventral hippocampus (vHPC) has been implicated in aspects of fear and/or anxiety. In this study, we tested the hypothesis that vHPC may be a critical subregion for performance on a delay-based, cost-benefit decision making task. Rats chose between the two goal arms of a T maze, one containing an immediately available small reward, the other containing a larger reward that was only accessible after a delay. dHPC, vHPC, and complete hippocampal (cHPC) lesions all reduced choice of the delayed high reward (HR) in favor of the immediately available low reward (LR). The deficits were not due to a complete inability to remember which reward size was associated with which arm of the maze. When an equivalent 10-s delay was introduced in both goal arms, all rats chose the HR arm on nearly all trials. The deficit was, however, reinstated when the inequality was reintroduced. Our results suggest an important role for both dHPC and vHPC in the extended neural circuitry that underlies intertemporal choice