Your Attack Is Too DUMB: Formalizing Attacker Scenarios for Adversarial Transferability

Evasion attacks are a threat to machine learning models, where adversaries attempt to affect classifiers by injecting malicious samples. An alarming side-effect of evasion attacks is their ability to transfer among different models: this property is called transferability. Therefore, an attacker can produce adversarial samples on a custom model (surrogate) to conduct the attack on a victim's organization later. Although literature widely discusses how adversaries can transfer their attacks, their experimental settings are limited and far from reality. For instance, many experiments consider both attacker and defender sharing the same dataset, balance level (i.e., how the ground truth is distributed), and model architecture. In this work, we propose the DUMB attacker model. This framework allows analyzing if evasion attacks fail to transfer when the training conditions of surrogate and victim models differ. DUMB considers the following conditions: Dataset soUrces, Model architecture, and the Balance of the ground truth. We then propose a novel testbed to evaluate many state-of-the-art evasion attacks with DUMB; the testbed consists of three computer vision tasks with two distinct datasets each, four types of balance levels, and three model architectures. Our analysis, which generated 13K tests over 14 distinct attacks, led to numerous novel findings in the scope of transferable attacks with surrogate models. In particular, mismatches between attackers and victims in terms of dataset source, balance levels, and model architecture lead to non-negligible loss of attack performance.Comment: Accepted at RAID 202

Non-perturbative renormalization of lattice four-fermion operators without power subtractions

A general nonperturbative analysis of the renormalization properties of Delta I = 3/2 four-fermion operators in the framework of lattice regularization with Wilson fermions is presented. We discuss the nonperturbative determination of the operator renormalization constants in the lattice regularization independent (RI or MOM) scheme. We also discuss the determination of the finite lattice subtraction coefficients from Ward identities. We prove that, at large external virtualities, the determination of the lattice mixing coefficients, obtained using the RI renormalization scheme, is equivalent to that based on Ward identities, in the continuum and chiral limits. As a feasibility study of our method, we compute the mixing matrix at several renormalization scales, for three Values of the lattice coupling beta, using the Wilson and tree-level improved SW-Clover actions

Single-Dose Intracardiac Injection of Pro-Regenerative MicroRNAs Improves Cardiac Function After Myocardial Infarction

Rationale: Recent evidence indicates that a few human microRNAs (miRNAs), in particular hsa-miR-199a-3p and hsa-miR-590-3p, stimulate proliferation of cardiomyocytes and, once expressed in the mouse heart using viral vectors, induce cardiac regeneration after myocardial infarction. Viral vectors, however, are not devoid of safety issues and, more notably, drive expression of the encoded miRNAs for indefinite periods of time, which might not be desirable in light of human therapeutic application. Objective: As an alternative to the use of viral vectors, we wanted to assess the efficacy of synthetic miRNA mimics in inducing myocardial repair after single intracardiac injection using synthetic lipid formulations. Methods and Results: We comparatively analyzed the efficacy of different lipid formulations in delivering hsa-miR-199a-3p and hsa-miR-590-3p both in primary neonatal mouse cardiomyocytes and in vivo. We established a transfection protocol allowing persistence of these two mimics for at least 12 days after a single intracardiac injection, with minimal dispersion to other organs and long-term preservation of miRNA functional activity, as assessed by monitoring the expression of two direct mRNA targets. Administration of this synthetic formulation immediately after myocardial infarction in mice resulted in marked reduction of infarct size and persistent recovery of cardiac function. Conclusions: A single administration of synthetic miRNA-lipid formulations is sufficient to stimulate cardiac repair and restoration of cardiac function

B-parameters of the complete set of matrix elements of (Delta B = 2) operators from the lattice

We compute on the lattice the ``bag'' parameters of the five (Delta B = 2) operators of the supersymmetric basis, by combining their values determined in full QCD and in the static limit of HQET. The extrapolation of the QCD results from the accessible heavy-light meson masses to the B-meson mass is constrained by the static result. The matching of the corresponding results in HQET and in QCD is for the first time made at NLO accuracy in the MSbar(NDR) renormalization scheme. All results are obtained in the quenched approximation.Comment: 27 pages (5 figures

Dendrimersomes: a new vesicular nano-platform for MR-molecular imaging applications

A new class of nanovesicles formed by the self-assembly of amphiphilic Janus dendrimers, dendrimersomes, loaded with hydrophilic or amphiphilic magnetic resonance imaging chelates shows promising properties as a novel, efficient and versatile nano platform for biomedical imaging

Polarity studies of single polyelectrolyte layers in polyelectrolyte multilayers probed by steady state and life time doxorubicin fluorescence

Hypothesis: Polarity in polyelectrolyte multilayers (PEMs) may vary from the inner to the top layers of the film as the charge compensation of the layers is more effective inside the PEMs than in outer layers. Doxorubicin hydrochloride (DX) is used here to sense polarity at the single polyelectrolyte level inside PEMS. Experimental: DX is complexed electrostatically to a polyanion, either polystyrene sulfonate (PSS) or polyacrylic acid (PAA) and assembled at selected positions in a multilayer of the polyanion and polyally lamine hydrochloride (PAH) as polycation. Local polarity in the layer domain is evaluated through changes in the intensity ratio of the first to second band of spectra of DX (I1/I2 ratio) by steady state flu orescence, and by Lifetime fluorescence. Findings: PAH/PSS multilayers, show a polarity similar to water with DX/PSS as top layer, decreasing to I1/ I2 ratios similar to organic solvents as the number of polyelectrolyte layers assembled on top increases. For PAH/PAA multilayers, polarity values reflect a more polar environment than water when DX/PAA is the top layer, remaining unaltered by the assembly of polyelectrolyte layers on top. Results show that different polar environments may be present in a PEM when considering polarity at the single layer level.Fil: Martinelli, Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; Argentina. Centro de Investigación Cooperativa en Biomateriales; EspañaFil: Tasca, Elisamaria. Centro de Investigación Cooperativa en Biomateriales; España. Università degli Studi di Roma "La Sapienza"; ItaliaFil: Andreozzi, Patrizia. Università degli Studi di Firenze; Dipartimento di Chimica “Ugo Schiff”; Italia. Centro de Investigación Cooperativa en Biomateriales; EspañaFil: Libertone, Sara. Centro de Investigación Cooperativa en Biomateriales; EspañaFil: Ritacco, Hernán Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; ArgentinaFil: Giustini, Mauro. Università degli Studi di Roma "La Sapienza"; Italia. Università degli Studi di Firenze; Dipartimento di Chimica “Ugo Schiff” ; ItaliaFil: Moya, Sergio Enrique. Centro de Investigación Cooperativa en Biomateriales; España. Università degli Studi di Roma "La Sapienza"; Itali

In Vivo Therapeutic Potential of Mesenchymal Stromal Cells Depends on the Source and the Isolation Procedure

SummaryOver the last several years, mesenchymal stromal cells (MSCs) have been isolated from different tissues following a variety of different procedures. Here, we comparatively assess the ex vivo and in vivo properties of MSCs isolated from either adipose tissue or bone marrow by different purification protocols. After MSC transplantation into a mouse model of hindlimb ischemia, clinical and histological analysis revealed that bone marrow MSCs purified on adhesive substrates exerted the best therapeutic activity, preserving tissue viability and promoting formation of new arterioles without directly transdifferentiating into vascular cells. In keeping with these observations, these cells abundantly expressed cytokines involved in vessel maturation and cell retention. These findings indicate that the choice of MSC source and purification protocol is critical in determining the therapeutic potential of these cells and warrant the standardization of an optimal MSC isolation procedure in order to select the best conditions to move forward to more effective clinical experimentation

New frontiers of cognitive rehabilitation in geriatric age: the Mozart effect (ME)

The ME was described for the first time in 1993. Subsequently other studies with similar designs were performed. The present study, therefore, proposes: (i) to verify the existence of the benefits of exposure to music in elderly subjects with mild cognitive impairment (MCI), (ii) to explore whether it is possible to find any lasting improvement after training, conducted for a long period of time, with such musical pieces, in the measurable cognitive performances. The study we conducted showed that the ME is present in geriatric patients with MCI; the influence on spatial–temporal abilities remains constant in time if the stimulation is maintained. The continuation of our study will consist of increasing the number of individuals examined and in having them listen to music during the study of ECG rhythms and during the acquisition of cerebral functional magnetic resonance imaging (fMRI), and, at the same time, testing them by neuropsychometric methods

Fischer–Tropsch Synthesis: Effect of the Promoter’s Ionic Charge and Valence Level Energy on Activity

In this contribution, we examine the effect of the promoter´s ionic charge and valence orbital energy on the catalytic activity of Fe-based catalysts, based on in situ synchrotron X-ray powder diffraction (SXRPD), temperature-programmed-based techniques (TPR, TPD, CO-TP carburization), and Fischer–Tropsch synthesis catalytic testing studies. We compared the promoting effects of K (a known promoter for longer-chained products) with Ba, which has a similar ionic radius but has double the ionic charge. Despite being partially “buried” in a crystalline BaCO3 phase, the carburization of the Ba-promoted catalyst was more effective than that of K; this was primarily due to its higher (2+) ionic charge. With Ba2+, higher selectivity to methane and lighter products were obtained compared to the K-promoted catalysts; this is likely due to Ba´s lesser capability of suppressing H adsorption on the catalyst surface. An explanation is provided in terms of a more limited mixing between electron-filled Ba2+ 5p and partially filled Fe 3d orbitals, which are expected to be important for the chemical promotion, as they are further apart in energy compared to the K+ 3p and Fe 3d orbitals