Generic Black-Box End-to-End Attack Against State of the Art API Call Based Malware Classifiers

In this paper, we present a black-box attack against API call based machine learning malware classifiers, focusing on generating adversarial sequences combining API calls and static features (e.g., printable strings) that will be misclassified by the classifier without affecting the malware functionality. We show that this attack is effective against many classifiers due to the transferability principle between RNN variants, feed forward DNNs, and traditional machine learning classifiers such as SVM. We also implement GADGET, a software framework to convert any malware binary to a binary undetected by malware classifiers, using the proposed attack, without access to the malware source code.Comment: Accepted as a conference paper at RAID 201

Swelling From Down Under... The Patella

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The Nature of Eddy Kinetic Energy in the Labrador Sea: Different Types of Mesoscale Eddies, their Temporal Variability and Impact on Deep Convection

Oceanic eddies are an important component in preconditioning the central Labrador Sea (LS) for deep convection and in restratifying the convected water. This study investigates the different sources and impacts of Eddy Kinetic Energy (EKE) and its temporal variability in the LS with the help of a 52-year long hindcast simulation of a 1/20° ocean model. Irminger Rings (IR) are generated in the West Greenland Current (WGC) between 60 and 62°N, mainly affect preconditioning and limit the northward extent of the convection area. The IR exhibit a seasonal cycle and decadal variations linked to the WGC strength, varying with the circulation of the subpolar gyre. The mean and temporal variations of IR generation can be attributed to changes in deep ocean baroclinic and upper ocean barotropic instabilities at comparable magnitudes. The main source of EKE and restratification in the central LS are Convective Eddies (CE). They are generated by baroclinic instabilities near the bottom of the mixed layer during and after convection. The CE have a mid-depth core and reflect the hydrographic properties of the convected water mass with a distinct minimum in potential vorticity. Their seasonal to decadal variability is tightly connected to the local atmospheric forcing and the associated air-sea heat fluxes. A third class of eddies in the LS are the Boundary Current Eddies shed from the Labrador Current (LC). Since they are mostly confined to the vicinity of the LC, these eddies appear to exert only minor influence on preconditioning and restratification

Decadal variability of Eddy Kinetic Energy in the South Pacific Subtropical Countercurrent in an Ocean General Circulation Model

The Eddy Kinetic Energy (EKE) associated with the Subtropical Countercurrent (STCC) in the western subtropical South Pacific is known to exhibit substantial seasonal and decadal variability. Using an eddy-permitting ocean general circulation model, which is able to reproduce the observed, salient features of the seasonal cycles of shear, stratification, baroclinic production and the associated EKE, we investigate the decadal changes of EKE. We show that the STCC region exhibits, uniquely among the subtropical gyres of the world’s oceans, significant, atmospherically forced, decadal EKE variability. The decadal variations are driven by changing vertical shear between the STCC in the upper 300 m and the South Equatorial Current below, predominantly caused by variations in STCC strength associated with a changing meridional density gradient. In the 1970s, an increased meridional density gradient results in EKE twice as large as in later decades in the model. Utilizing sensitivity experiments, decadal variations in the wind field are shown to be the essential driver. Local wind stress curl anomalies associated with the Interdecadal Pacific Oscillation (IPO) lead to up- and downwelling of the thermocline, inducing strengthening or weakening of the STCC and the associated EKE. Additionally, remote wind stress curl anomalies in the eastern subtropical South Pacific, which are not related to the IPO, generate density anomalies that propagate westward as Rossby waves and can account for up to 30–40 % of the density anomalies in the investigated region

Activity Tracking and Improved Health Outcomes

Activity tracking devices are a popular way for health-minded individuals to measure daily movement and estimate energy expenditure. Tracking, in its many forms, has been proven to improve health outcomes. From paper diaries to devices and smartphone applications, these data are becoming more important and have the potential to be used in the physician’s office as part of a realistic physical activity plan for improved health outcomes. As a health-care professional, amid a rapidly expanding accelerometer market, it is important to know the application and practicality of these devices, as well as the evidence behind an individual\u27s usage. What we choose to recommend, as health-care professionals, can influence the health and well-being of patients in the wellness arena. This chapter will look at research focused on activity tracking, including metrics such as sleep, nutrition, and physical activity, and health outcomes to further educate health-care professionals in an ever-evolving field

Secondary Metabolism Inducing Treatments During In Vitro Development of Turmeric (Curcuma longa L.) Rhizomes

Turmeric (Curcuma longa L.) plants that were grown in vitro for 17 or 22 weeks as a fed-batch culture in 2.5 L vessels yielded 39 to 43 g and 62 to 70 g of fresh rhizomes per vessel, respectively (95 % confidence interval). The MS liquid medium was maintained at 6 % sucrose through media addition twice during the experiment. Various methods were employed in attempts to increase secondary metabolism. Antioxidant and total phenolics assays were employed to characterize phytochemical activity. A first experiment exposed four clones to phenylalanine and/or methyl jasmonate (MeJa) from week 12 to 17 in culture. In a second experiment, a clone was given short-term exposure (1.5 weeks) to either proline, a natural proline-rich fish extract, MeJa, or chitosan beginning during the twentieth week of culture. This experiment also included a nitrogen stress treatment (weeks 16–22). The 5-week phenylalanine and MeJa treatments lowered biomass accumulation and antioxidant capacity of the tissue. The magnitude of antioxidant depression was dependent on genotype and, within each genotype, the degree of depression was similar for phenylalanine and MeJa, alone and in combination. In the second experiment, only the low-nitrogen treatment yielded an increase in phenolic content to 4.7 % of dry weight compared to untreated microrhizomes (4.1 % of dry weight). Nitrogen-stressed plants also had less leaf growth, but rhizome mass was unaffected and averaged 63 g FW per vessel. None of the short-term treatments had a significant effect on biomass, antioxidant capacity, or phenolic content. None of the treatments significantly affected radical scavenging, although the low-nitrogen treatment might have improved this activity (p = .1207). Results indicated that plants grown in a high-nitrogen MS media were not responsive to elicitation

T Cells Contain an RNase-Insensitive Inhibitor of APOBEC3G Deaminase Activity

The deoxycytidine deaminase APOBEC3G (A3G) is expressed in human T cells and inhibits HIV-1 replication. When transfected into A3G-deficient epithelial cell lines, A3G induces catastrophic hypermutation by deaminating the HIV-1 genome. Interestingly, studies suggest that endogenous A3G in T cells induces less hypermutation than would be expected. However, to date, the specific deaminase activity of endogenous A3G in human CD4+ T cells has not been examined directly. Here, we compared deaminase activity of endogenous and exogenous A3G in various human cell lines using a standard assay and a novel, quantitative, high-throughput assay. Exogenous A3G in epithelial cell lysates displayed deaminase activity only following RNase treatment, as expected given that A3G is known to form an enzymatically inactive RNA-containing complex. Surprisingly, comparable amounts of endogenous A3G from T cell lines or from resting or activated primary CD4+ T cells exhibited minimal deaminase activity, despite RNase treatment. Specific deaminase activity of endogenous A3G in H9, CEM, and other T cell lines was up to 36-fold lower than specific activity of exogenous A3G in epithelial-derived cell lines. Furthermore, RNase-treated T cell lysates conferred a dose-dependent inhibition to epithelial cell lysates expressing enzymatically active A3G. These studies suggest that T cells, unlike epithelial-derived cell lines, express an unidentified RNase-resistant factor that inhibits A3G deaminase activity. This factor could be responsible for reduced levels of hypermutation in T cells, and its identification and blockade could offer a means for increasing antiretroviral intrinsic immunity of T cells

Competing effects of mass anisotropy and spin Zeeman coupling on the upper critical field of a mixed dd- and s-wave superconductor

Based on the linearized Eilenberger equations, the upper critical field $(H_{c2})$ of mixed d- and s-wave superconductors has been microscopically studied with an emphasis on the competing effects of mass anisotropy and spin Zeeman coupling. We find the mass anisotropy always enhance $H_{c2}$ while the Zeeman interaction suppresses $H_{c2}$. As required by the thermodynamics, we find $H_{c2}$ is saturated at zero temperature. We compare the theoretical calculations with recent experimental data of YBa$_{2}$Cu$_{3}$O$_{7-+AFw-delta}$.Comment: To appear in PRB in Feb. 200