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Hardware support for isolated execution (such as Intel SGX) enables development of applications that keep their code and data confidential even while running on a hostile or compromised host. However, automatically verifying that such applications satisfy confidentiality remains challenging. We present a methodology for designing such applications in a way that enables certifying their confidentiality. Our methodology consists of forcing the application to communicate with the external world through a narrow interface, compiling it with runtime checks that aid verification, and linking it with a small runtime library that implements the interface. The runtime library includes core services such as secure communication channels and memory management. We formalize this restriction on the application as Information Release Confinement (IRC), and we show that it allows us to decompose the task of proving confidentiality into (a) one-time, human-assisted functional verification of the runtime to ensure that it does not leak secrets, (b) automatic verification of the application's machine code to ensure that it satisfies IRC and does not directly read or corrupt the runtime's internal state. We present /CONFIDENTIAL: A verifier for IRC that is modular, automatic, and keeps our compiler out of the trusted computing base. Our evaluation suggests that the methodology scales to real-world applications.

Security-critical applications constantly face threats from exploits in lower computing layers such as the operating system, virtual machine monitors, or even attacks from malicious administrators. To help protect application secrets from such attacks, there is increasing interest in hardware implementations of primitives for trusted computing, such as Intel's Software Guard Extensions (SGX) instructions. These primitives enable hardware protection of memory regions containing code and data, and provide a root of trust for measurement, remote attestation, and cryptographic sealing. However, vulnerabilities in the application itself, such as the incorrect use of SGX instructions or memory safety errors, can be exploited to divulge secrets. In this paper, we introduce a new approach to formally model these primitives and formally verify properties of so-called enclave programs that use them. More specifically, we create formal models of relevant aspects of SGX, develop several adversary models, and present a sound verification methodology (based on automated theorem proving and information ow analysis) for proving that an enclave program running on SGX does not contain a vulnerability that causes it to reveal secrets to the adversary. We introduce Moat, a tool which formally verifies confidentiality properties of applications running on SGX. We evaluate Moat on several applications, including a one time password scheme, off-the-record messaging, notary service, and secure query processing.

Malathy Krishnamurthy,1 Margaret M Lemmon,1 Evan M Falcinelli,1 Reuel A Sandy,1 Jennifer N Dootz,1 Tiffany M Mott,1 Sathish Rajamani,1,2 Kurt E Schaecher,3 Allen J Duplantier,1,4 Rekha G Panchal11Department of Target Discovery and Experimental Microbiology, Division of Molecular and Translational Sciences, United States Army Medical Research Institute of Infectious Diseases, Frederick, MD, USA; 2General Dynamics Information Technology, Frederick, MD, USA; 3Department of Pathology, Walter Reed National Military Medical Center, Bethesda, MD, USA; 4Cherokee Nation Assurance, Frederick, MD, USAPurpose: The rapid emergence of multidrug-resistant (MDR) bacteria and the lack of new therapies to eliminate them poses a major threat to global health. With the alarming rise in antimicrobial resistance (AMR), focus has now shifted to the use of the polymyxin class of antibiotics as the last line of defense for treatment of Gram-negative infections. Unfortunately, the growing resistance of bacteria against polymyxins is threatening the treatment of MDR infections, necessitating the need for novel strategies. The objective of this study was to determine if combination of polymyxin (polymyxin B or colistin) with a nonantibiotic small molecule AR-12, a celecoxib derivative that is devoid of cyclooxygenase 2 (COX-2) inhibitory activities, can be an effective strategy against polymyxin-resistant MDR bacteria.Methods: Growth inhibition studies, time-kill assays and permeability assays were conducted to investigate the effect of AR-12 on the antibacterial activity of polymyxins.Results: Growth studies were performed on a panel of polymyxin-resistant MDR strains using the combination of AR-12 with either colistin or polymyxin B. The combination treatment had no effect on strains that have inherent polymyxin resistance; however, AR-12 was effective in lowering the minimal inhibitory concentration (MIC) of polymyxins by 4–60-fold in several strains that had acquired polymyxin resistance. Time-kill assays using the combination of AR-12 and colistin with select MDR strains suggest rapid killing and bactericidal activity, while the permeability assays using fluorescently labeled dansylated polymyxin and 1-N-phenylnaphthylamine (NPN) in these MDR strains suggest that AR-12 can potentiate the antibacterial activity of polymyxins by possibly altering the bacterial outer membrane via modification of lipopolysaccharide and thereby improving the uptake of polymyxins.Conclusion: Our studies indicate that the combination of AR-12 and polymyxin is effective in targeting select Gram-negative bacteria that have acquired polymyxin resistance. Further understanding of the mechanism of action of AR-12 will provide new avenues for developing narrow-spectrum antibacterials to target select Gram-negative MDR bacteria. Importantly, our studies show that the use of nonantibiotic small molecules in combination with polymyxins is an attractive strategy to counter the growing resistance of bacteria to polymyxins.Keywords: Gram-negative, MDR bacteria, potentiator, antimicrobial resistance

The current work communicates the entropy generation analysis of oscillating flow of magnetohydrodynamic couple stress nanofluid in a vertical channel. The main objective of present study is to examine the entropy analysis of a magnetohydrodynamic couple stress nanofluid. In this study, water and ethylene glycol (50:50) and diamond are used as the base fluid and nanoparticles, respectively. The effects of radiative heat, Ohmic, and viscous dissipation are all considered. By employing the perturbation process, the governing partial differential equations are transformed into the set of ordinary differential equations, which are then deciphered by implementing the Runge-Kutta fourth-order scheme with shooting technique. The obtained outcomes reveal that, amplifying viscous dissipation promising the temperature whereas the reverse is true for the influence of couple stress viscosity and Hartmann number. Heat transfer rate is decelerating with the boost up in Hartmann number at the walls while it is accelerating with the increment in viscous dissipation at the right wall. Entropy is escalating for intensifying viscous dissipation, and thermal radiation whereas the reverse is true for the impression of couple stress viscosity, and volume fraction of nanoparticles. Bejan number is falling for escalating volume fraction of nanoparticles, and viscous dissipation while it is enhancing with escalation in couple stress parameter. [ABSTRACT FROM AUTHOR]

Environmental challenges in treatment and disposal of tannery effluent with high salinity, stringent environmental regulations including Total Dissolved Solids (TDS), etc. resulted in development of new appropriate cleaner production process to reduce the volume of water usage, pollutional discharges, segregation of streams such as saline soak liquor, spent chrome liquor enable to adopt advanced aerobic oxidation process, membrane system, recovery of chromium, purified salt and water for reuse. The achievements of the innovative cleaner production and effluent treatment are : (i) Reduction in water usage in soaking process from 6000-8000 liters to less than 3000 liters/ton of hides, (ii) Segregation of high saline streams from soaking operations and spent chrome liquor for separate treatment and recovery of quality salt, chromium in form of cake/powder, (iii) Conversion of physiochemical treatment into biological treatment with reduced chemical usage and sludge generation by about 70% and (iv) Advanced oxidation treatment using ozone for achieving COD, colour and turbidity. Viable cleaner production and sustainable treatment technologies had been engineered and are being implemented in a major leather cluster with more than 200 new tanneries, a Common Effluent Treatment Plant. This would become a biggest leather cluster development during this century in World Leather Sector. [ABSTRACT FROM AUTHOR]

In this study, the magnetohydrodynamic pulsatile flow of a couple stress nanofluid in a channel has been discussed in detail by adopting Buongiorno's nanofluid model. The impacts of Brownian motion, thermophoresis, Ohmic heating, viscous dissipation and chemical reaction on heat, and mass transfer of blood based nanofluid are considered. The current concept is significant in the field of nano-drug supply, dynamics of physiological fluids, and biomedicines. The governing partial differential equations are converted into a set of ODEs (ordinary differential equations) by employing a perturbation scheme. The resulting non-dimensional system is numerically interpreted to determine the impact of various emerging parameters on flow variables by utilizing the shooting technique with the support of the Runge-Kutta procedure. The outcomes reveal that the temperature rises with the magnifying viscous dissipation, Brownian motion, and thermophoresis parameters, whereas the opposite trend can be seen with an escalation in the couple stress parameter. Heat transfer rate is an accelerating function of Brownian motion and thermophoresis parameters while it is a decelerating function of couple stress parameter and Hartmann number. Mass transfer rate declines with increasing values of thermophoresis parameter and Lewis number. [ABSTRACT FROM AUTHOR]