Privacy-Preserving Image Template Sharing Using Contrastive Learning

With the recent developments of Machine Learning as a Service (MLaaS), various privacy concerns have been raised. Having access to the user’s data, an adversary can design attacks with different objectives, namely, reconstruction or attribute inference attacks. In this paper, we propose two different training frameworks for an image classification task while preserving user data privacy against the two aforementioned attacks. In both frameworks, an encoder is trained with contrastive loss, providing a superior utility-privacy trade-off. In the reconstruction attack scenario, a supervised contrastive loss was employed to provide maximal discrimination for the targeted classification task. The encoded features are further perturbed using the obfuscator module to remove all redundant information. Moreover, the obfuscator module is jointly trained with a classifier to minimize the correlation between private feature representation and original data while retaining the model utility for the classification. For the attribute inference attack, we aim to provide a representation of data that is independent of the sensitive attribute. Therefore, the encoder is trained with supervised and private contrastive loss. Furthermore, an obfuscator module is trained in an adversarial manner to preserve the privacy of sensitive attributes while maintaining the classification performance on the target attribute. The reported results on the CelebA dataset validate the effectiveness of the proposed frameworks.     

Ecofriendly and Efficient One-Pot Procedure for the Synthesis of Quinazoline Derivatives Catalyzed by an Acidic Ionic Liquid Under Aerobic Oxidation Conditions

A three-component condensation reaction between 2-aminobenzophenone derivatives, formaldehyde or aromatic aldehydes, and ammonium acetate efficiently provides substituted quinazolines in a one-pot reaction in the presence of Brönsted acidic ionic liquid, 1-methylimidazolium triflouroacetate ([Hmim]TFA), in conjunction with aerobic oxidation. The ionic liquid was separated from the reaction mixture by simple extraction and was recycled three times without considerable loss in activity.     

Vacuum solution of a linear red-shift based correction in <Emphasis Type="Italic">f</Emphasis> (<Emphasis Type="Italic">R</Emphasis>) gravity

In this paper we have considered a red-shift based linear correction in derivative of action in the context of vacuum f (R) gravity. Here we have found out that the linear correction may describe the late time acceleration which is appeared by SuperNovae Ia with no need of dark energy. Also we have calculated the asymptotic action for the desired correction. The value of all solutions may reduce to de’ Sitter universe in the absence of correction term.     

An efficient one-pot method for the synthesis of novel ferrocene-triamide conjugates via pseudo five-component reaction

A simple and efficient one-pot synthesis of novel ferrocene-triamide conjugates from the reaction of ferrocenecarboxaldehyde with Meldrum’s acid and isocyanides in the presence of NH-containing compounds is described. This transformation proceeds through the creation of two CC bonds, two CN bonds, and one CO bond, leading to three peptide bonds, and presumably occurs via a domino sequence involving Knoevenagel condensation, [1+4] cycloaddition, deacetonation, and aminolysis reactions.     

Signature of non-Fickian solute transport in complex heterogeneous porous media

We simulate transport of a solute through three-dimensional images of different rock samples, with resolutions of a few microns, representing geological media of increasing pore-scale complexity: a sandpack, a Berea sandstone, and a Portland limestone. We predict the propagators (concentration as a function of distance) measured on similar cores in nuclear magnetic resonance experiments and the dispersion coefficient as a function of Péclet number and time. The behavior is explained using continuous time random walks with a truncated power-law distribution of travel times: transport is qualitatively different for the complex limestone compared to the sandstone or sandpack, with long tailing, an almost immobile peak concentration, and a very slow approach to asymptotic dispersion.     

Silica Gel Supported Ferric Perchlorate: A New and Efficient Reagent for One Pot Synthesis of Amides from Benzylic Alcohols

Benzylic alcohols react efficiently with nitriles in the presence of silica gel supported ferric perchlorate to produce amides in high yields.     

Diammonium Hydrogen Phosphate as a Neutral and Efficient Catalyst for Synthesis of 1,8‐Dioxo‐octahydroxanthene Derivatives in Aqueous Media

A new and efficient method to synthesize a 3,3,6,6,9‐aryl‐1,8‐dioxo‐octahydroxanthene derivative using diammonium hydrogen phosphate as catalyst was performed in water at room temperature in a short periods.