Gazelle: A Low Latency Framework for Secure Neural Network Inference

The growing popularity of cloud-based machine learning raises a natural question about the privacy guarantees that can be provided in such a setting. Our work tackles this problem in the context where a client wishes to classify private images using a convolutional neural network (CNN) trained by a server. Our goal is to build efficient protocols whereby the client can acquire the classification result without revealing their input to the server, while guaranteeing the privacy of the server's neural network. To this end, we design Gazelle, a scalable and low-latency system for secure neural network inference, using an intricate combination of homomorphic encryption and traditional two-party computation techniques (such as garbled circuits). Gazelle makes three contributions. First, we design the Gazelle homomorphic encryption library which provides fast algorithms for basic homomorphic operations such as SIMD (single instruction multiple data) addition, SIMD multiplication and ciphertext permutation. Second, we implement the Gazelle homomorphic linear algebra kernels which map neural network layers to optimized homomorphic matrix-vector multiplication and convolution routines. Third, we design optimized encryption switching protocols which seamlessly convert between homomorphic and garbled circuit encodings to enable implementation of complete neural network inference. We evaluate our protocols on benchmark neural networks trained on the MNIST and CIFAR-10 datasets and show that Gazelle outperforms the best existing systems such as MiniONN (ACM CCS 2017) by 20 times and Chameleon (Crypto Eprint 2017/1164) by 30 times in online runtime. Similarly when compared with fully homomorphic approaches like CryptoNets (ICML 2016) we demonstrate three orders of magnitude faster online run-time

Assembly of Graphene Oxide at Water/Oil Interfaces: Tessellated Nanotiles

The interfacial assembly of graphene oxide (GO) at the water/oil interface and its kinetics were systematically studied. GO nanosheets were found to segregate to the water/oil interface and interact with quaternized block copolymer chains by the peripheral carboxyl groups on the GO. If the interfacial area is decreased, then GO, assembled at and confined to the interface, jams and then buckles. An analysis of the kinetics of the assembly processes leads to the conclusion that the diffusion of GO to the interface is the rate-determining step. The morphology of the jammed GO film was investigated, and TEM images show that GO sheets form a mosaic or tile across the whole oil/water interface

Assembly of Graphene Oxide at Water/Oil Interfaces: Tessellated Nanotiles

The interfacial assembly of graphene oxide (GO) at the water/oil interface and its kinetics were systematically studied. GO nanosheets were found to segregate to the water/oil interface and interact with quaternized block copolymer chains by the peripheral carboxyl groups on the GO. If the interfacial area is decreased, then GO, assembled at and confined to the interface, jams and then buckles. An analysis of the kinetics of the assembly processes leads to the conclusion that the diffusion of GO to the interface is the rate-determining step. The morphology of the jammed GO film was investigated, and TEM images show that GO sheets form a mosaic or tile across the whole oil/water interface

Reduction-Responsive Carbon Dots for Real-Time Ratiometric Monitoring of Anticancer Prodrug Activation in Living Cells

Anticancer prodrugs have been extensively investigated to lower toxic side effects of common chemotherapeutic agents in biomedical fields. To illustrate the activation mechanism of anticancer prodrugs, fluorescent dyes or single-emission intensity alteration-based approaches have been widely used. However, fluorescent dyes often suffer from poor photostability and chemical stability, and single-emission intensity alteration-based methods cannot avoid the influence from uncontrolled microenvironment changes in living samples. To overcome these obstacles, herein, a fluorescence resonance energy transfer (FRET)-based ratiometric approach was successfully developed for real-time monitoring of anticancer prodrug activation. Excitation-wavelength-dependent and full-color-emissive carbon dots (CDs) were used as drug nanocarriers and FRET donor, and a cisplatin­(IV) prodrug was selected as the model drug and the linker to load the Dabsyl quencher on the surface of CDs. Owing to the FRET effect, the blue fluorescence of CDs was effectively quenched by the Dabsyl unit. Under reductive conditions in solution or in living cells for the reduction of cisplatin­(IV) prodrug to Pt­(II) species, the blue fluorescence of CDs increased over time, without apparent intensity change for green or red fluorescence. Thus, the gradually enhanced intensity ratio of blue-to-green or blue-to-red fluorescence could be indicative of the real-time reduction of the cisplatin­(IV) prodrug to cytotoxic Pt­(II) species. This ratiometric method could exclude the influence from complex biological microenvironments by using green or red fluorescence of CDs as an internal reference, which provides new insights into the activation of the cisplatin­(IV) prodrug and offers a great opportunity to design safe and effective anticancer therapeutics

Assembly of Acid-Functionalized Single-Walled Carbon Nanotubes at Oil/Water Interfaces

The efficient segregation of water-soluble, acid-functionalized, single-walled carbon nanotubes (SWCNTs) at the oil/water interface was induced by dissolving low-molecular-weight amine-terminated polystyrene (PS-NH₂) in the oil phase. Salt-bridge interactions between carboxylic acid groups of SWCNTs and amine groups of PS drove the assembly of SWCNTs at the interface, monitored by pendant drop tensiometry and laser scanning confocal microscopy. The impact of PS end-group functionality, PS and SWCNT concentrations, and the degree of SWCNT acid modification on the interfacial activity was assessed, and a sharp drop in interfacial tension was observed above a critical SWCNT concentration. Interfacial tensions were low enough to support stable oil/water emulsions. Further experiments, including potentiometric titrations and the replacement of SWCNTs by other carboxyl-containing species, demonstrated that the interfacial tension drop reflects the loss of SWCNT charge as the pH falls near/below the intrinsic carboxyl dissociation constant; species lacking multivalent carboxylic acid groups are inactive. The trapped SWCNTs appear to be neither ordered nor oriented

Dual-Responsive Carbon Dots for Tumor Extracellular Microenvironment Triggered Targeting and Enhanced Anticancer Drug Delivery

In this work, pH/redox dual-responsive carbon dots (CDs-RGD-Pt­(IV)-PEG) were fabricated for tumor extracellular microenvironment triggered targeting and enhanced anticancer drug delivery. The system consists of fluorescent carbon dots as imaging-guided drug nanocarriers, cisplatin­(IV) as prodrug, and RGD peptide as active targeting ligand, which is covered by monomethoxypolyethylene glycol (mPEG) through tumor extracellular pH (6.5–6.8) responsive benzoic-imine bond. The drug nanocarriers could be tracked by multicolor fluorescence of carbon dots. After the hydrolysis of benzoic-imine bond at the tumor extracellular pH to expose the inner targeting RGD peptide, the drug nanocarriers showed effective uptake by cancer cells through RGD-integrin α_<i>v</i>β₃ (ligand–receptor) interaction. Upon the internalization, the loaded cisplatin­(IV) prodrug was reduced to cytotoxic cisplatin in reductive cytosol of cancer cells to exhibit therapeutic effects. Confocal imaging, flow cytometry, and cell viability assays using CDs-RGD-Pt­(IV)-PEG were performed to reveal the enhanced uptake and better therapeutic efficiency to cancer cells with high integrin α_<i>v</i>β₃ expression at tumor extracellular pH than that in physiological condition. The developed CDs-RGD-Pt­(IV)-PEG offers a new strategy to provide safe and effective therapeutic agents based on carbon dots for promising cancer therapy

Supplementary document for Surface damage induced by micropores in transparent ceramics under nanosecond laser irradiation - 6887700.pdf

Size and density distribution information of micro pores in transparent ceramics after air annealing

Charge-Convertible Carbon Dots for Imaging-Guided Drug Delivery with Enhanced <i>in Vivo</i> Cancer Therapeutic Efficiency

Carbon dots (CDs) are remarkable nanocarriers due to their promising optical and biocompatible capabilities. However, their practical applicability in cancer therapeutics is limited by their insensitive surface properties to complicated tumor microenvironment <i>in vivo</i>. Herein, a tumor extracellular microenvironment-responsive drug nanocarrier based on cisplatin­(IV) prodrug-loaded charge-convertible CDs (CDs–Pt­(IV)@PEG-(PAH/DMMA)) was developed for imaging-guided drug delivery. An anionic polymer with dimethylmaleic acid (PEG-(PAH/DMMA)) on the fabricated CDs–Pt­(IV)@PEG-(PAH/DMMA) could undergo intriguing charge conversion to a cationic polymer in mildly acidic tumor extracellular microenvironment (pH ∼ 6.8), leading to strong electrostatic repulsion and release of positive CDs–Pt­(IV). Importantly, positively charged nanocarrier displays high affinity to negatively charged cancer cell membrane, which results in enhanced internalization and effective activation of cisplatin­(IV) prodrug in the reductive cytosol. The <i>in vitro</i> experimental results confirmed that this promising charge-convertible nanocarrier possesses better therapeutic efficiency under tumor extracellular microenvironment than normal physiological condition and noncharge-convertible nanocarrier. The <i>in vivo</i> experiments further demonstrated high tumor-inhibition efficacy and low side effects of the charge-convertible CDs, proving its capability as a smart drug nanocarrier with enhanced therapeutic effects. The present work provides a strategy to promote potential clinical application of CDs in the cancer treatment

A new tremulane sesquiterpenoid from the fungus <i>Irpex lacteus</i>

<p>A new tremulane sesquiterpenoid, named irlactam A (<b>1</b>), was isolated from cultures of the fungus <i>Irpex lacteus</i>. The new structure was elucidated by spectroscopic data analysis. The compound was tested for its cytotoxicities on HL-60, SMMC-7721, A-549, MCF-7, and SW480 cells and for its inhibitory activity against isozymes of 11<i>β</i>-hydroxysteroid dehydrogenases (11<i>β</i>-HSD).</p

A new cadinane sesquiterpenoid from cultures of the Basidiomycete <i>Panus conchatus</i>

<p>A new cadinane sesquiterpenoid, named panutorulon A (<b>1</b>), was isolated from cultures of the basidiomycete <i>Panus conchatus</i>. The new structure was elucidated by means of spectroscopic methods. Compound <b>1</b> was tested for its cytotoxicity against five human cancer cell lines and for its inhibitory activity against isozymes of 11<i>β</i>-hydroxysteroid dehydrogenases (11<i>β</i>-HSD).</p