Adversarial attacks hidden in plain sight

Convolutional neural networks have been used to achieve a string of successes during recent years, but their lack of interpretability remains a serious issue. Adversarial examples are designed to deliberately fool neural networks into making any desired incorrect classification, potentially with very high certainty. Several defensive approaches increase robustness against adversarial attacks, demanding attacks of greater magnitude, which lead to visible artifacts. By considering human visual perception, we compose a technique that allows to hide such adversarial attacks in regions of high complexity, such that they are imperceptible even to an astute observer. We carry out a user study on classifying adversarially modified images to validate the perceptual quality of our approach and find significant evidence for its concealment with regards to human visual perception

Pointlike probes of superstring-theoretic superfluids

In analogy with an experimental setup used in liquid helium, we use a pointlike probe to study superfluids which have a gravity dual. In the gravity description, the probe is represented by a hanging string. We demonstrate that there is a critical velocity below which the probe particle feels neither drag nor stochastic forces. Above this critical velocity, there is power-law scaling for the drag force, and the stochastic forces are characterized by a finite, velocity-dependent temperature. This temperature participates in two simple and general relations between the drag force and stochastic forces. The formula we derive for the critical velocity indicates that the low-energy excitations are massless, and they demonstrate the power of stringy methods in describing strongly coupled superfluids.Comment: 17 pages, 2 figures, added a figure, a reference, and moved material to an appendi

Sequences of dipole black rings and Kaluza-Klein bubbles

We construct new exact solutions to 5D Einstein-Maxwell equations describing sequences of Kaluza-Klein bubbles and dipole black rings. The solutions are generated by 2-soliton transformations from vacuum black ring - bubble sequences. The properties of the solutions are investigated. We also derive the Smarr-like relations and the mass and tension first laws in the general case for such configurations of Kaluza-Klein bubbles and dipole black rings. The novel moment is the appearance of the magnetic flux in the Smarr-like relations and the first laws.Comment: 26 pages, 1 figur

ASEAN and the development of counter-terrorism law and policy in Southeast Asia

This is the final version of the article. Available from the publisher via the link in this record

Colliding AdS gravitational shock waves in various dimensions and holography

The formation of marginally trapped surfaces in the off-center collision of two shock waves on AdS_D (with D=4,5,6,7 and 8) is studied numerically. We focus on the case when the two waves collide with nonvanishing impact parameter while the sources are located at the same value of the holographic coordinate. In all cases a critical value of the impact parameter is found above which no trapped surface is formed. The numerical results show the existence of a simple scaling relation between the critical impact parameter and the energy of the colliding waves. Using the isometries of AdS_D we relate the solutions obtained to the ones describing the collision of two waves with a purely holographic impact parameter. This provides a gravitational dual for the head-on collision of two lumps of energy of unequal size.Comment: 25 pages, 11 figures. v2: minor changes, typos corrected. To appear in JHE

Does buyer-seller similarity affect buyer satisfaction with the seller firm?

With the increased reliance on diverse markets in multi-cultural contexts, the role that similarity can play in the relationship between a salesperson and a buyer is receiving increased attention. Similarity is regarded as the cornerstone of positive communications, and salespeople rely on the trust that can be created by this recognition of likeness. However, there are different types of similarity, and not all have an equal bearing on the salesperson-buyer relationship. In this study, we examine similarity in appearance, similarity in lifestyle, and similarity in status. Most studies go no further than examining the effect of similarity on a buyer’s satisfaction with a salesperson, and to date there appear to be few studies relating to the effect of similarity on satisfaction with a firm. This study examines the effect of similarity on a buyer’s sense of satisfaction with a firm represented by a salesperson in the banking context. The results of the study show that appearance similarity and status similarity have a significant effect on the salesperson-buyer relationship, whereas lifestyle similarity has no effect. The buyer’s satisfaction with a salesperson is found to mediate the relationship between similarity in appearance and the buyer’s satisfaction with a firm. In this paper, we discuss these findings and look at their implications for both research and practice. Findings of the study are particularly important because of New Zealand’s increasing interaction with Asia and its people, which has transformed New Zealand to become a multi-cultural and multi-ethnic country

End‐to‐end continuous bioprocessing: impact on facility design, cost of goods and cost of development for monoclonal antibodies

This article presents a systematic approach to evaluate the business case for continuous processing that captures trade-offs between manufacturing and development costs for monoclonal antibodies (mAbs). A decisional tool was built that integrated cost of goods (COG) with cost of development models and new equipment sizing equations tailored to batch, hybrid and end-to-end continuous processes. The COG analysis predicted that single-use continuous facilities (sized using a dedicated DSP train per bioreactor) offer more significant commercial COG savings over stainless steel batch facilities at annual demands of 100-500 kg (~35%), compared to tonnage demands of 1-3 tons (~±10%) that required multiple parallel continuous trains. Single-use batch facilities were found to compete with continuous options on COG only at 100 kg/year. For the scenarios where batch and continuous facilities offered similar COG, the analysis identified the windows of operation required to reach different COG savings with thresholds for the perfusion rate, volumetric productivity and media cost. When considering the project lifecycle cost, the analysis indicated that while end-to-end continuous facilities may struggle to compete on development costs, they become more cost-effective than stainless steel batch facilities when considering the total out-of-pocket cost across both drug development and commercial activities. This article is protected by copyright. All rights reserved

p-wave Holographic Superconductors and five-dimensional gauged Supergravity

We explore five-dimensional ${\cal N}=4$ $SU(2)\times U(1)$ and ${\cal N}=8$ SO(6) gauged supergravities as frameworks for condensed matter applications. These theories contain charged (dilatonic) black holes and 2-forms which have non-trivial quantum numbers with respect to U(1) subgroups of SO(6). A question of interest is whether they also contain black holes with two-form hair with the required asymptotic to give rise to holographic superconductivity. We first consider the ${\cal N}=4$ case, which contains a complex two-form potential $A_{\mu\nu}$ which has U(1) charge $\pm 1$. We find that a slight generalization, where the two-form potential has an arbitrary charge $q$, leads to a five-dimensional model that exhibits second-order superconducting transitions of p-wave type where the role of order parameter is played by $A_{\mu\nu}$, provided $q \gtrsim 5.6$. We identify the operator that condenses in the dual CFT, which is closely related to ${\cal N}=4$ Super Yang-Mills theory with chemical potentials. Similar phase transitions between R-charged black holes and black holes with 2-form hair are found in a generalized version of the ${\cal N}=8$ gauged supergravity Lagrangian where the two-forms have charge $q\gtrsim 1.8$.Comment: 35 pages, 14 figure

Effects of dietary mannanoligosaccharide on performance of Japanese quail affected by aflatoxicosis

The potential of the yeast component, mannanoligosaccharide (MOS) to ameliorate the effects of aflatoxicosis was examined in growing Japanese quail. The product was incorporated in the diet at 1 g/kg and was evaluated for its ability to reduce the deleterious effects of 2 mg total aflatoxin (AF; 82.30% AFB1, 2.06% AFB2, 7.68% AFG1 and 7.96% AFG2)/kg diet on Japanese quail chicks from 10 to 45 days of age. Forty 10-d old Japanese quail chicks were assigned in a 2x2 factorial arrangement of treatments to four groups (Control, AF, MOS, AF plus MOS), each consisting of 10 quails. The addition of AF alone significantly decreased feed consumption and body weight gain from the first week onwards. A significant adverse effect of AF on the feed conversion ratio was also observed from week 4 onwards. The addition of MOS to the AF-containing diet significantly reduced these adverse effects of AF on feed consumption, body weight gain and feed conversion ratio. The cumulative body weight gain was 22.0% lower in the quails consuming a diet containing AF without MOS as compared to the control group. However, it was only 2.3% lower that the control in the birds fed the diet containing the AF plus MOS. Key Words: Aflatoxin, Mannanoligosaccharide, Quail, Preventive effect South African Journal of Animal Science Vol.34(3) 2004: 144-14