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Most chip designers outsource the manufacturing of their integrated circuits (ICs) to external foundries due to the exorbitant cost and complexity of the process. This involvement of untrustworthy, external entities opens the door to major security threats, such as reverse engineering (RE). RE can reveal the physical structure and functionality of intellectual property (IP) and ICs, leading to IP theft, counterfeiting, and other misuses. The concept of the threshold voltage-defined (TVD) logic family is a potential mechanism to obfuscate and protect the design and prevent RE. However, it addresses post-fabrication RE issues, and it has been shown that dopant profiling techniques can be used to determine the threshold voltage of the transistor and break the obfuscation. In this work, we propose a novel TVD modulation with ion-sensitive field-effect transistors (ISFETs) to protect the IC from RE and IP piracy. Compared to the conventional TVD logic family, ISFET-TVD allows post-manufacture programming. The ISFET-TVD logic gate can be reconfigured after fabrication, maintaining an exact schematic architecture with an identical layout for all types of logic gates, and thus overcoming the shortcomings of the classic TVD. The threshold voltage of the ISFETs can be adjusted after fabrication by changing the ion concentration of the material in contact with the ion-sensitive gate of the transistor, depending on the Boolean functionality. The ISFET is CMOS compatible, and therefore implemented on 45 nm CMOS technology for demonstration.

Shock waves are a phenomenon that can be produced under constrained conditions inside a shock tube. These waves have a wide scope of studies due to their multi-disciplinary applications. Therefore, in the present work, the main focus is to conduct transient numerical simulations of a small-scale shock tube which has been designed and fabricated. Comparison of 1D, 2D, and 3D cases, and grid independence studies have been carried out successfully along with parametric study by variation of driver section pressures. Simulations are conducted using the open-source Computational Continuum Mechanics toolbox, OpenFOAM®. Processing of the simulated data is carried out using Paraview via quantitative and qualitative methods.

Design of printed circuit board (PCB) stack-up requires the consideration of characteristic impedance, insertion loss and crosstalk. As there are many parameters in a PCB stack-up design, the optimization of these parameters needs to be efficient and accurate. A less optimal stack-up would lead to expensive PCB material choices in high speed designs. In this paper, an efficient global optimization method using parallel and intelligent Bayesian optimization is proposed for the stripline design., Comment: 3 Pages

BACKGROUND CONTEXT Modern cervical spine surgeries utilizes intraoperative neuromonitoring (IONM) in the form of motor evoked potential (MEP), somatosensory evoked potential (SSEP) and electromyography (EMG). However, with a sensitivity ranging from 0% to 100% and specificity ranging from 27% to 100%, there is a need to differentiate between true and false positive signal changes to better supplement intraoperative management. PURPOSE To compare the incidence of neurological deficits in sustained, bimodal intraoperative neuromonitoring (MEP and SEP) signal drops to that of unimodal or transient changes in cervical spine surgeries. STUDY DESIGN/SETTING Retrospective cohort study. PATIENT SAMPLE A total of 257 cases of cervical spine surgery with multimodal neuromonitoring in 3 hospitals in Singapore between 2013 and 2017. OUTCOME MEASURES Incidence of neurological deficits in 3 different patterns of neuromonitoring signal changes. Sensitivity and specifity of MEP and SSEP in cervical spine surgeries. METHODS A retrospective review of IONM and clinical records of all cervical spine surgeries in three hospitals between 2013 and 2017. The procedures were performed by fellowship trained spine surgeons and multimodal IONM was used in all cases. Clinical records were evaluated by two clinicians who were not involved in the patients' management. IONM records of MEP and SSEP were reviewed by a trained neurophysiology technologist. Results were grouped into three groups. In Group 0, there were unimodal signal drops that were transient and resolved back to baseline by the end of surgery. In Group 1, there were sustained unimodal signal changes while in Group 2, there were sustained drops in both the MEP and SSEP. RESULTS A total of 257 cases were reviewed and 207 cases were analyzed after exclusions. A total of 52/207 (25.1%) cases had IONM changes. A total of 10/207 (4.3%) of cases were in Group 0, while Group 1 had 35/207 (16.9%) of cases. 7/207 (3.4%) of cases were in Group 2. Group 0 and 1 had no neurological deficits, while in Group 2, 2/7 (28.6%) had neurological deficits. Both MEP and SSEP were 100% sensitive. SSEP had a specificity of 96.6%, while MEP had a lower specificity at 76.6%. CONCLUSIONS Our study shows that by grouping the signal changes into transient or sustained, and unimodal or bimodal, we are able to better predict which signal drops are significant, thereby allowing for improved intraoperative decision making. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

The purpose of this investigation was to develop a ketoconazole cream with rosin for both topical and systemic delivery. Creams were prepared by using rosin as one of the components in different proportions with different cream base combinations. The drug excipients interaction studies were carried out and results revealed that there is no interaction between the drug and the excipients used in the formulation. The prepared creams were evaluated for their physicochemical properties, pH, viscosity, particle size, drug content and in vitro release studies. The release of the drug, ketoconazole was measured for eight hours and compared with a standard marketed formulation. The formulation (F8) fulfilled all topical formulation parameters; it can be used for the systemic topical drug delivery.